Added --exclude-from feature.

(Slightly modified by apenwarr)
Document missing --dns option in sshuttle manpage
2025-06-20 09:57:42 +02:00 · 2012-07-06 15:13:30 -04:00 · 2012-07-06 15:06:07 -04:00 · 2012-07-06 15:00:28 -04:00 · 2012-07-06 15:00:28 -04:00 · 2012-04-19 23:00:29 -07:00
148 changed files with 8190 additions and 12436 deletions
--- a/.envrc
+++ b/.envrc
@ -1 +0,0 @@
 use flake .
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@ -1,13 +0,0 @@
 version: 2
 enable-beta-ecosystems: true
 updates:
 - package-ecosystem: uv
  directory: "/"
  schedule:
    interval: daily
  open-pull-requests-limit: 10
 - package-ecosystem: github-actions
  directory: "/"
  schedule:
    interval: daily
  open-pull-requests-limit: 10
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@ -1,70 +0,0 @@
 # For most projects, this workflow file will not need changing; you simply need
 # to commit it to your repository.
 #
 # You may wish to alter this file to override the set of languages analyzed,
 # or to provide custom queries or build logic.
 #
 # ******** NOTE ********
 # We have attempted to detect the languages in your repository. Please check
 # the `language` matrix defined below to confirm you have the correct set of
 # supported CodeQL languages.
 #
 name: "CodeQL"
 on:
  push:
    branches: [ master ]
  pull_request:
    # The branches below must be a subset of the branches above
    branches: [ master ]
  schedule:
    - cron: '31 21 * * 3'
 jobs:
  analyze:
    name: Analyze
    runs-on: ubuntu-latest
    permissions:
      actions: read
      contents: read
      security-events: write
    strategy:
      fail-fast: false
      matrix:
        language: [ 'python' ]
        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python', 'ruby' ]
        # Learn more about CodeQL language support at https://git.io/codeql-language-support
    steps:
    - name: Checkout repository
      uses: actions/checkout@v4
    # Initializes the CodeQL tools for scanning.
    - name: Initialize CodeQL
      uses: github/codeql-action/init@v3
      with:
        languages: ${{ matrix.language }}
        # If you wish to specify custom queries, you can do so here or in a config file.
        # By default, queries listed here will override any specified in a config file.
        # Prefix the list here with "+" to use these queries and those in the config file.
        # queries: ./path/to/local/query, your-org/your-repo/queries@main
    # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
    # If this step fails, then you should remove it and run the build manually (see below)
    - name: Autobuild
      uses: github/codeql-action/autobuild@v3
    # ℹ️ Command-line programs to run using the OS shell.
    # 📚 https://git.io/JvXDl
    # ✏️ If the Autobuild fails above, remove it and uncomment the following three lines
    #    and modify them (or add more) to build your code if your project
    #    uses a compiled language
    #- run: |
    #   make bootstrap
    #   make release
    - name: Perform CodeQL Analysis
      uses: github/codeql-action/analyze@v3
--- a/.github/workflows/pythonpackage.yml
+++ b/.github/workflows/pythonpackage.yml
@ -1,38 +0,0 @@
 # This workflow will install Python dependencies, run tests and lint with a variety of Python versions
 # For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
 name: Python package
 on:
  push:
    branches: [ master ]
  pull_request:
    branches: [ master ]
  workflow_dispatch: {}
 jobs:
  build:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        python-version: ["3.9", "3.10", "3.11", "3.12"]
        poetry-version: ["main"]
    steps:
    - uses: actions/checkout@v4
    - name: Set up Python ${{ matrix.python-version }}
      uses: actions/setup-python@v5
      with:
        python-version: ${{ matrix.python-version }}
    - name: Install uv
      uses: astral-sh/setup-uv@v6
      with:
        version: "0.4.30"
        enable-cache: true
        cache-dependency-glob: "uv.lock"
    - name: Install the project
      run: uv sync --all-extras --dev
    - name: Lint with flake8
      run: uv run flake8 sshuttle tests --count --show-source --statistics
    - name: Run the automated tests
      run: uv run pytest -v
--- a/.github/workflows/release-please.yml
+++ b/.github/workflows/release-please.yml
@ -1,66 +0,0 @@
 on:
  push:
    branches:
      - master
 name: release-please
 jobs:
  release-please:
    runs-on: ubuntu-latest
    permissions:
      contents: write
      pull-requests: write
    outputs:
      release_created: ${{ steps.release.outputs.release_created }}
      tag_name: ${{ steps.release.outputs.tag_name }}
    steps:
      - uses: googleapis/release-please-action@v4
        id: release
        with:
          token: ${{ secrets.MY_RELEASE_PLEASE_TOKEN }}
          release-type: python
  build-pypi:
    name: Build for pypi
    needs: [release-please]
    if: ${{ needs.release-please.outputs.release_created == 'true' }}
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v4
    - name: Set up Python 3.12
      uses: actions/setup-python@v5
      with:
        python-version: 3.12
    - name: Install uv
      uses: astral-sh/setup-uv@v6
      with:
        version: "0.4.30"
        enable-cache: true
        cache-dependency-glob: "uv.lock"
    - name: Build project
      run: uv build
    - name: Store the distribution packages
      uses: actions/upload-artifact@v4
      with:
        name: python-package-distributions
        path: dist/
  upload-pypi:
    name: Upload to pypi
    needs: [build-pypi]
    runs-on: ubuntu-latest
    environment:
      name: pypi
      url: https://pypi.org/p/sshuttle
    permissions:
      id-token: write
    steps:
    - name: Download all the dists
      uses: actions/download-artifact@v4
      with:
        name: python-package-distributions
        path: dist/
    - name: Publish package distributions to PyPI
      uses: pypa/gh-action-pypi-publish@release/v1
--- a/.gitignore
+++ b/.gitignore
@ -1,20 +1,6 @@
 /tmp/
 /.coverage
 /.cache/
 /.eggs/
 /.tox/
 /build/
 /dist/
 /sshuttle.egg-info/
 /docs/_build/
 *.pyc
 *~
 *.8
 /.do_built
 /.do_built.dir
 /.redo
 /.pytest_cache/
 /.python-version
 /.direnv/
 /result
 /.vscode/
--- a/.prospector.yml
+++ b/.prospector.yml
@ -1,24 +0,0 @@
 strictness: medium
 pylint:
  disable:
    - too-many-statements
    - too-many-locals
    - too-many-function-args
    - too-many-arguments
    - too-many-branches
    - bare-except
    - protected-access
    - no-else-return
    - unused-argument
    - method-hidden
    - arguments-differ
    - wrong-import-position
    - raising-bad-type
 pep8:
  options:
    max-line-length: 79
 mccabe:
  run: false
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@ -1,13 +0,0 @@
 version: 2
 build:
  os: ubuntu-20.04
  tools:
    python: "3.10"
  jobs:
    post_install:
      - pip install uv
      - UV_PROJECT_ENVIRONMENT=$READTHEDOCS_VIRTUALENV_PATH uv sync --all-extras --group docs --link-mode=copy
 sphinx:
  configuration: docs/conf.py
--- a/.tool-versions
+++ b/.tool-versions
@ -1 +0,0 @@
 python 3.10.6
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@ -1,54 +0,0 @@
 # Changelog
 ## [1.3.1](https://github.com/sshuttle/sshuttle/compare/v1.3.0...v1.3.1) (2025-03-25)
 ### Bug Fixes
 * add pycodestyle config ([5942376](https://github.com/sshuttle/sshuttle/commit/5942376090395d0a8dfe38fe012a519268199341))
 * add python lint tools ([ae3c022](https://github.com/sshuttle/sshuttle/commit/ae3c022d1d67de92f1c4712d06eb8ae76c970624))
 * correct bad version number at runtime ([7b66253](https://github.com/sshuttle/sshuttle/commit/7b662536ba92d724ed8f86a32a21282fea66047c))
 * Restore "nft" method ([375810a](https://github.com/sshuttle/sshuttle/commit/375810a9a8910a51db22c9fe4c0658c39b16c9e7))
 ## [1.3.0](https://github.com/sshuttle/sshuttle/compare/v1.2.0...v1.3.0) (2025-02-23)
 ### Features
 * switch to a network namespace on Linux ([8a123d9](https://github.com/sshuttle/sshuttle/commit/8a123d9762b84f168a8ca8c75f73e590954e122d))
 ### Bug Fixes
 * prevent UnicodeDecodeError parsing iptables rule with comments ([cbe3d1e](https://github.com/sshuttle/sshuttle/commit/cbe3d1e402cac9d3fbc818fe0cb8a87be2e94348))
 * remove temp build hack ([1f5e6ce](https://github.com/sshuttle/sshuttle/commit/1f5e6cea703db33761fb1c3f999b9624cf3bc7ad))
 * support ':' sign in password ([7fa927e](https://github.com/sshuttle/sshuttle/commit/7fa927ef8ceea6b1b2848ca433b8b3e3b63f0509))
 ### Documentation
 * replace nix-env with nix-shell ([340ccc7](https://github.com/sshuttle/sshuttle/commit/340ccc705ebd9499f14f799fcef0b5d2a8055fb4))
 * update installation instructions ([a2d405a](https://github.com/sshuttle/sshuttle/commit/a2d405a6a7f9d1a301311a109f8411f2fe8deb37))
 ## [1.2.0](https://github.com/sshuttle/sshuttle/compare/v1.1.2...v1.2.0) (2025-02-07)
 ### Features
 * Add release-please to build workflow ([d910b64](https://github.com/sshuttle/sshuttle/commit/d910b64be77fd7ef2a5f169b780bfda95e67318d))
 ### Bug Fixes
 * Add support for Python 3.11 and Python 3.11 ([a3396a4](https://github.com/sshuttle/sshuttle/commit/a3396a443df14d3bafc3d25909d9221aa182b8fc))
 * bad file descriptor error in windows, fix pytest errors ([d4d0fa9](https://github.com/sshuttle/sshuttle/commit/d4d0fa945d50606360aa7c5f026a0f190b026c68))
 * drop Python 3.8 support ([1084c0f](https://github.com/sshuttle/sshuttle/commit/1084c0f2458c1595b00963b3bd54bd667e4cfc9f))
 * ensure poetry works for Python 3.9 ([693ee40](https://github.com/sshuttle/sshuttle/commit/693ee40c485c70f353326eb0e8f721f984850f5c))
 * fix broken workflow_dispatch CI rule ([4b6f7c6](https://github.com/sshuttle/sshuttle/commit/4b6f7c6a656a752552295863092d3b8af0b42b31))
 * Remove more references to legacy Python versions ([339b522](https://github.com/sshuttle/sshuttle/commit/339b5221bc33254329f79f2374f6114be6f30aed))
 * replace requirements.txt files with poetry ([85dc319](https://github.com/sshuttle/sshuttle/commit/85dc3199a332f9f9f0e4c6037c883a8f88dc09ca))
 * replace requirements.txt files with poetry (2) ([d08f78a](https://github.com/sshuttle/sshuttle/commit/d08f78a2d9777951d7e18f6eaebbcdd279d7683a))
 * replace requirements.txt files with poetry (3) ([62da705](https://github.com/sshuttle/sshuttle/commit/62da70510e8a1f93e8b38870fdebdbace965cd8e))
 * replace requirements.txt files with poetry (4) ([9bcedf1](https://github.com/sshuttle/sshuttle/commit/9bcedf19049e5b3a8ae26818299cc518ec03a926))
 * update nix flake to fix problems ([cda60a5](https://github.com/sshuttle/sshuttle/commit/cda60a52331c7102cff892b9b77c8321e276680a))
 * use Python &gt;= 3.10 for docs ([bf29464](https://github.com/sshuttle/sshuttle/commit/bf294643e283cef9fb285d44e307e958686caf46))
--- a/CHANGES.rst
+++ b/CHANGES.rst
@ -1,315 +0,0 @@
 ==========
 Change log
 ==========
 Release notes now moved to https://github.com/sshuttle/sshuttle/releases/
 These are the old release notes.
 1.0.5 - 2020-12-29
 ------------------
 Added
 ~~~~~
 * IPv6 support in nft method.
 * Intercept DNS requests sent by systemd-resolved.
 * Set default tmark.
 * Fix python2 server compatibility.
 * Python 3.9 support.
 Fixed
 ~~~~~
 * Change license text to LGPL-2.1
 * Fix #494 sshuttle caught in infinite select() loop.
 * Include sshuttle version in verbose output.
 * Add psutil as dependency in setup.py
 * When subnets and excludes are specified with hostnames, use all IPs.
 * Update/document client's handling of IPv4 and IPv6.
 * Update sdnotify.py documentation.
 * Allow no remote to work.
 * Make prefixes in verbose output more consistent.
 * Make nat and nft rules consistent; improve rule ordering.
 * Make server and client handle resolv.conf differently.
 * Fix handling OSError in FirewallClient#__init__
 * Refactor automatic method selection.
 Removed
 ~~~~~~~
 * Drop testing of Python 3.5
 1.0.4 - 2020-08-24
 ------------------
 Fixed
 ~~~~~
 * Allow Mux() flush/fill to work with python < 3.5
 * Fix parse_hostport to always return string for host.
 * Require -r/--remote parameter.
 * Add missing package in OpenWRT documentation.
 * Fix doc about --listen option.
 * README: add Ubuntu.
 * Increase IP4 ttl to 63 hops instead of 42.
 * Fix formatting in installation.rst
 1.0.3 - 2020-07-12
 ------------------
 Fixed
 ~~~~~
 * Ask setuptools to require Python 3.5 and above.
 * Add missing import.
 * Fix formatting typos in usage docs
 1.0.2 - 2020-06-18
 ------------------
 Fixed
 ~~~~~
 * Leave use of default port to ssh command.
 * Remove unwanted references to Python 2.7 in docs.
 * Replace usage of deprecated imp.
 * Fix connection with @ sign in username.
 1.0.1 - 2020-06-05
 ------------------
 Fixed
 ~~~~~
 * Errors in python long_documentation.
 1.0.0 - 2020-06-05
 ------------------
 Added
 ~~~~~
 * Python 3.8 support.
 * sshpass support.
 * Auto sudoers file (#269).
 * option for latency control buffer size.
 * Docs: FreeBSD'.
 * Docs: Nix'.
 * Docs: openwrt'.
 * Docs: install instructions for Fedora'.
 * Docs: install instructions for Arch Linux'.
 * Docs: 'My VPN broke and need a solution fast'.
 Removed
 ~~~~~~~
 * Python 2.6 support.
 * Python 2.7 support.
 Fixed
 ~~~~~
 * Remove debug message for getpeername failure.
 * Fix crash triggered by port scans closing socket.
 * Added "Running as a service" to docs.
 * Systemd integration.
 * Trap UnicodeError to handle cases where hostnames returned by DNS are invalid.
 * Formatting error in CHANGES.rst
 * Various errors in documentation.
 * Nftables based method.
 * Make hostwatch locale-independent (#379).
 * Add tproxy udp port mark filter that was missed in #144, fixes #367.
 * Capturing of local DNS servers.
 * Crashing on ECONNABORTED.
 * Size of pf_rule, which grew in OpenBSD 6.4.
 * Use prompt for sudo, not needed for doas.
 * Arch linux installation instructions.
 * tests for existing PR-312 (#337).
 * Hyphen in hostname.
 * Assembler import (#319).
 0.78.5 - 2019-01-28
 -------------------
 Added
 ~~~~~
 * doas support as replacement for sudo on OpenBSD.
 * Added ChromeOS section to documentation (#262)
 * Add --no-sudo-pythonpath option
 Fixed
 ~~~~~
 * Fix forwarding to a single port.
 * Various updates to documentation.
 * Don't crash if we can't look up peername
 * Fix missing string formatting argument
 * Moved sshuttle/tests into tests.
 * Updated bandit config.
 * Replace path /dev/null by os.devnull.
 * Added coverage report to tests.
 * Fixes support for OpenBSD (6.1+) (#282).
 * Close stdin, stdout, and stderr when using syslog or forking to daemon (#283).
 * Changes pf exclusion rules precedence.
 * Fix deadlock with iptables with large ruleset.
 * docs: document --ns-hosts --to-ns and update --dns.
 * Use subprocess.check_output instead of run.
 * Fix potential deadlock condition in nft_get_handle.
 * auto-nets: retrieve routes only if using auto-nets.
 0.78.4 - 2018-04-02
 -------------------
 Added
 ~~~~~
 * Add homebrew instructions.
 * Route traffic by linux user.
 * Add nat-like method using nftables instead of iptables.
 Changed
 ~~~~~~~
 * Talk to custom DNS server on pod, instead of the ones in /etc/resolv.conf.
 * Add new option for overriding destination DNS server.
 * Changed subnet parsing. Previously 10/8 become 10.0.0.0/8.  Now it gets
  parsed as 0.0.0.10/8.
 * Make hostwatch find both fqdn and hostname.
 * Use versions of python3 greater than 3.5 when available (e.g. 3.6).
 Removed
 ~~~~~~~
 * Remove Python 2.6 from automatic tests.
 Fixed
 ~~~~~
 * Fix case where there is no --dns.
 * [pf] Avoid port forwarding from loopback address.
 * Use getaddrinfo to obtain a correct sockaddr.
 * Skip empty lines on incoming routes data.
 * Just skip empty lines of routes data instead of stopping processing.
 * [pf] Load pf kernel module when enabling pf.
 * [pf] Test double restore (ipv4, ipv6) disables only once; test kldload.
 * Fixes UDP and DNS proxies binding to the same socket address.
 * Mock socket bind to avoid depending on local IPs being available in test box.
 * Fix no value passed for argument auto_hosts in hw_main call.
 * Fixed incorrect license information in setup.py.
 * Preserve peer and port properly.
 * Make --to-dns and --ns-host work well together.
 * Remove test that fails under OSX.
 * Specify pip requirements for tests.
 * Use flake8 to find Python syntax errors or undefined names.
 * Fix compatibility with the sudoers file.
 * Stop using SO_REUSEADDR on sockets.
 * Declare 'verbosity' as global variable to placate linters.
 * Adds 'cd sshuttle' after 'git' to README and docs.
 * Documentation for loading options from configuration file.
 * Load options from a file.
 * Fix firewall.py.
 * Move sdnotify after setting up firewall rules.
 * Fix tests on Macos.
 0.78.3 - 2017-07-09
 -------------------
 The "I should have done a git pull" first release.
 Fixed
 ~~~~~
 * Order first by port range and only then by swidth
 0.78.2 - 2017-07-09
 -------------------
 Added
 ~~~~~
 * Adds support for tunneling specific port ranges (#144).
 * Add support for iproute2.
 * Allow remote hosts with colons in the username.
 * Re-introduce ipfw support for sshuttle on FreeBSD with support for --DNS option as well.
 * Add support for PfSense.
 * Tests and documentation for systemd integration.
 * Allow subnets to be given only by file (-s).
 Fixed
 ~~~~~
 * Work around non tabular headers in BSD netstat.
 * Fix UDP and DNS support on Python 2.7 with tproxy method.
 * Fixed tests after adding support for iproute2.
 * Small refactoring of netstat/iproute parsing.
 * Set started_by_sshuttle False after disabling pf.
 * Fix punctuation and explain Type=notify.
 * Move pytest-runner to tests_require.
 * Fix warning: closed channel got=STOP_SENDING.
 * Support sdnotify for better systemd integration.
 * Fix #117 to allow for no subnets via file (-s).
 * Fix argument splitting for multi-word arguments.
 * requirements.rst: Fix mistakes.
 * Fix typo, space not required here.
 * Update installation instructions.
 * Support using run from different directory.
 * Ensure we update sshuttle/version.py in run.
 * Don't print python version in run.
 * Add CWD to PYTHONPATH in run.
 0.78.1 - 2016-08-06
 -------------------
 * Fix readthedocs versioning.
 * Don't crash on ENETUNREACH.
 * Various bug fixes.
 * Improvements to BSD and OSX support.
 0.78.0 - 2016-04-08
 -------------------
 * Don't force IPv6 if IPv6 nameservers supplied. Fixes #74.
 * Call /bin/sh as users shell may not be POSIX compliant. Fixes #77.
 * Use argparse for command line processing. Fixes #75.
 * Remove useless --server option.
 * Support multiple -s (subnet) options. Fixes #86.
 * Make server parts work with old versions of Python. Fixes #81.
 0.77.2 - 2016-03-07
 -------------------
 * Accidentally switched LGPL2 license with GPL2 license in 0.77.1 - now fixed.
 0.77.1 - 2016-03-07
 -------------------
 * Use semantic versioning. http://semver.org/
 * Update GPL 2 license text.
 * New release to fix PyPI.
 0.77 - 2016-03-03
 -----------------
 * Various bug fixes.
 * Fix Documentation.
 * Add fix for MacOS X issue.
 * Add support for OpenBSD.
 0.76 - 2016-01-17
 -----------------
 * Add option to disable IPv6 support.
 * Update documentation.
 * Move documentation, including man page, to Sphinx.
 * Use setuptools-scm for automatic versioning.
 0.75 - 2016-01-12
 -----------------
 * Revert change that broke sshuttle entry point.
 0.74 - 2016-01-10
 -----------------
 * Add CHANGES.rst file.
 * Numerous bug fixes.
 * Python 3.5 fixes.
 * PF fixes, especially for BSD.
--- a/Documentation/.gitignore
+++ b/Documentation/.gitignore
@ -0,0 +1,3 @@
 *.8
 /md-to-man
 /*.md.tmp
--- a/Documentation/all.do
+++ b/Documentation/all.do
@ -0,0 +1,5 @@
 /bin/ls *.md |
 sed 's/\.md/.8/' |
 xargs redo-ifchange
 redo-always
--- a/Documentation/clean.do
+++ b/Documentation/clean.do
@ -0,0 +1 @@
 rm -f *~ .*~ *.8 t/*.8 md-to-man *.tmp t/*.tmp
--- a/Documentation/default.8.do
+++ b/Documentation/default.8.do
@ -0,0 +1,2 @@
 redo-ifchange md-to-man $2.md.tmp
 . ./md-to-man $1 $2 $3
--- a/Documentation/default.md.tmp.do
+++ b/Documentation/default.md.tmp.do
@ -0,0 +1,3 @@
 redo-ifchange ../version/vars $2.md
 . ../version/vars
 sed -e "s/%VERSION%/$TAG/" -e "s/%DATE%/$DATE/" $2.md
--- a/Documentation/md-to-man.do
+++ b/Documentation/md-to-man.do
@ -0,0 +1,8 @@
 redo-ifchange md2man.py
 if ./md2man.py </dev/null >/dev/null; then
 	echo './md2man.py $2.md.tmp'
 else
 	echo "Warning: md2man.py missing modules; can't generate manpages." >&2
 	echo "Warning: try this: sudo easy_install markdown BeautifulSoup" >&2
 	echo 'echo Skipping: $2.1 >&2'
 fi
--- a/Documentation/md2man.py
+++ b/Documentation/md2man.py
@ -0,0 +1,278 @@
 #!/usr/bin/env python
 import sys, os, markdown, re
 from BeautifulSoup import BeautifulSoup
 def _split_lines(s):
    return re.findall(r'([^\n]*\n?)', s)
 class Writer:
    def __init__(self):
        self.started = False
        self.indent = 0
        self.last_wrote = '\n'
    def _write(self, s):
        if s:
            self.last_wrote = s
            sys.stdout.write(s)
    def writeln(self, s):
        if s:
            self.linebreak()
            self._write('%s\n' % s)
    def write(self, s):
        if s:
            self.para()
            for line in _split_lines(s):
                if line.startswith('.'):
                    self._write('\\&' + line)
                else:
                    self._write(line)
    def linebreak(self):
        if not self.last_wrote.endswith('\n'):
            self._write('\n')
    def para(self, bullet=None):
        if not self.started:
            if not bullet:
                bullet = ' '
            if not self.indent:
                self.writeln(_macro('.PP'))
            else:
                assert(self.indent >= 2)
                prefix = ' '*(self.indent-2) + bullet + ' '
                self.writeln('.IP "%s" %d' % (prefix, self.indent))
            self.started = True
    def end_para(self):
        self.linebreak()
        self.started = False
    def start_bullet(self):
        self.indent += 3
        self.para(bullet='\\[bu]')
    def end_bullet(self):
        self.indent -= 3
        self.end_para()
 w = Writer()
 def _macro(name, *args):
    if not name.startswith('.'):
        raise ValueError('macro names must start with "."')
    fixargs = []
    for i in args:
        i = str(i)
        i = i.replace('\\', '')
        i = i.replace('"', "'")
        if (' ' in i) or not i:
            i = '"%s"' % i
        fixargs.append(i)
    return ' '.join([name] + list(fixargs))
 def macro(name, *args):
    w.writeln(_macro(name, *args))
 def _force_string(owner, tag):
    if tag.string:
        return tag.string
    else:
        out = ''
        for i in tag:
            if not (i.string or i.name in ['a', 'br']):
                raise ValueError('"%s" tags must contain only strings: '
                                 'got %r: %r' % (owner.name, tag.name, tag))
            out += _force_string(owner, i)
        return out
 def _clean(s):
    s = s.replace('\\', '\\\\')
    return s
 def _bitlist(tag):
    if getattr(tag, 'contents', None) == None:
        for i in _split_lines(str(tag)):
            yield None,_clean(i)
    else:
        for e in tag:
            name = getattr(e, 'name', None)
            if name in ['a', 'br']:
                name = None  # just treat as simple text
            s = _force_string(tag, e)
            if name:
                yield name,_clean(s)
            else:
                for i in _split_lines(s):
                    yield None,_clean(i)
 def _bitlist_simple(tag):
    for typ,text in _bitlist(tag):
        if typ and not typ in ['em', 'strong', 'code']:
            raise ValueError('unexpected tag %r inside %r' % (typ, tag.name))
        yield text
 def _text(bitlist):
    out = ''
    for typ,text in bitlist:
        if not typ:
            out += text
        elif typ == 'em':
            out += '\\fI%s\\fR' % text
        elif typ in ['strong', 'code']:
            out += '\\fB%s\\fR' % text
        else:
            raise ValueError('unexpected tag %r inside %r' % (typ, tag.name))
    out = out.strip()
    out = re.sub(re.compile(r'^\s+', re.M), '', out)
    return out
 def text(tag):
    w.write(_text(_bitlist(tag)))
 # This is needed because .BI (and .BR, .RB, etc) are weird little state
 # machines that alternate between two fonts.  So if someone says something
 # like foo<b>chicken</b><b>wicken</b>dicken we have to convert that to
 #   .BI foo chickenwicken dicken
 def _boldline(l):
    out = ['']
    last_bold = False
    for typ,text in l:
        nonzero = not not typ
        if nonzero != last_bold:
            last_bold = not last_bold
            out.append('')
        out[-1] += re.sub(r'\s+', ' ', text)
    macro('.BI', *out)
 def do_definition(tag):
    w.end_para()
    macro('.TP')
    w.started = True
    split = 0
    pre = []
    post = []
    for typ,text in _bitlist(tag):
        if split:
            post.append((typ,text))
        elif text.lstrip().startswith(': '):
            split = 1
            post.append((typ,text.lstrip()[2:].lstrip()))
        else:
            pre.append((typ,text))
    _boldline(pre)
    w.write(_text(post))
 def do_list(tag):
    for i in tag:
        name = getattr(i, 'name', '').lower()
        if not name and not str(i).strip():
            pass
        elif name != 'li':
            raise ValueError('only <li> is allowed inside <ul>: got %r' % i)
        else:
            w.start_bullet()
            for xi in i:
                do(xi)
                w.end_para()
            w.end_bullet()
 def do(tag):
    name = getattr(tag, 'name', '').lower()
    if not name:
        text(tag)
    elif name == 'h1':
        macro('.SH', _force_string(tag, tag).upper())
        w.started = True
    elif name == 'h2':
        macro('.SS', _force_string(tag, tag))
        w.started = True
    elif name.startswith('h') and len(name)==2:
        raise ValueError('%r invalid - man page headers must be h1 or h2'
                         % name)
    elif name == 'pre':
        t = _force_string(tag.code, tag.code)
        if t.strip():
            macro('.RS', '+4n')
            macro('.nf')
            w.write(_clean(t).rstrip())
            macro('.fi')
            macro('.RE')
            w.end_para()
    elif name == 'p' or name == 'br':
        g = re.match(re.compile(r'([^\n]*)\n +: +(.*)', re.S), str(tag))
        if g:
            # it's a definition list (which some versions of python-markdown
            # don't support, including the one in Debian-lenny, so we can't
            # enable that markdown extension).  Fake it up.
            do_definition(tag)
        else:
            text(tag)
            w.end_para()
    elif name == 'ul':
        do_list(tag)
    else:
        raise ValueError('non-man-compatible html tag %r' % name)
 PROD='Untitled'
 VENDOR='Vendor Name'
 SECTION='9'
 GROUPNAME='User Commands'
 DATE=''
 AUTHOR=''
 lines = []
 if len(sys.argv) > 1:
    for n in sys.argv[1:]:
        lines += open(n).read().decode('utf8').split('\n')
 else:
    lines += sys.stdin.read().decode('utf8').split('\n')
 # parse pandoc-style document headers (not part of markdown)
 g = re.match(r'^%\s+(.*?)\((.*?)\)\s+(.*)$', lines[0])
 if g:
    PROD = g.group(1)
    SECTION = g.group(2)
    VENDOR = g.group(3)
    lines.pop(0)
 g = re.match(r'^%\s+(.*?)$', lines[0])
 if g:
    AUTHOR = g.group(1)
    lines.pop(0)
 g = re.match(r'^%\s+(.*?)$', lines[0])
 if g:
    DATE = g.group(1)
    lines.pop(0)
 g = re.match(r'^%\s+(.*?)$', lines[0])
 if g:
    GROUPNAME = g.group(1)
    lines.pop(0)
 inp = '\n'.join(lines)
 if AUTHOR:
    inp += ('\n# AUTHOR\n\n%s\n' % AUTHOR).replace('<', '\\<')
 html = markdown.markdown(inp)
 soup = BeautifulSoup(html, convertEntities=BeautifulSoup.HTML_ENTITIES)
 macro('.TH', PROD.upper(), SECTION, DATE, VENDOR, GROUPNAME)
 macro('.ad', 'l')  # left justified
 macro('.nh')  # disable hyphenation
 for e in soup:
    do(e)
--- a/Documentation/sshuttle.md
+++ b/Documentation/sshuttle.md
@ -0,0 +1,278 @@
 % sshuttle(8) Sshuttle %VERSION%
 % Avery Pennarun <apenwarr@gmail.com>
 % %DATE%
 # NAME
 sshuttle - a transparent proxy-based VPN using ssh
 # SYNOPSIS
 sshuttle [options...] [-r [username@]sshserver[:port]] \<subnets...\>
 # DESCRIPTION
 sshuttle allows you to create a VPN connection from your
 machine to any remote server that you can connect to via
 ssh, as long as that server has python 2.3 or higher.
 To work, you must have root access on the local machine,
 but you can have a normal account on the server.
 It's valid to run sshuttle more than once simultaneously on
 a single client machine, connecting to a different server
 every time, so you can be on more than one VPN at once.
 If run on a router, sshuttle can forward traffic for your
 entire subnet to the VPN.
 # OPTIONS
 \<subnets...\>
 :   a list of subnets to route over the VPN, in the form
    `a.b.c.d[/width]`.  Valid examples are 1.2.3.4 (a
    single IP address), 1.2.3.4/32 (equivalent to 1.2.3.4),
    1.2.3.0/24 (a 24-bit subnet, ie. with a 255.255.255.0
    netmask), and 0/0 ('just route everything through the
    VPN').
 -l, --listen=*[ip:]port*
 :   use this ip address and port number as the transparent
    proxy port.  By default sshuttle finds an available
    port automatically and listens on IP 127.0.0.1
    (localhost), so you don't need to override it, and
    connections are only proxied from the local machine,
    not from outside machines.  If you want to accept
    connections from other machines on your network (ie. to
    run sshuttle on a router) try enabling IP Forwarding in
    your kernel, then using `--listen 0.0.0.0:0`. 
 -H, --auto-hosts
 :   scan for remote hostnames and update the local /etc/hosts
    file with matching entries for as long as the VPN is
    open.  This is nicer than changing your system's DNS
    (/etc/resolv.conf) settings, for several reasons.  First,
    hostnames are added without domain names attached, so
    you can `ssh thatserver` without worrying if your local
    domain matches the remote one.  Second, if you sshuttle
    into more than one VPN at a time, it's impossible to
    use more than one DNS server at once anyway, but
    sshuttle correctly merges /etc/hosts entries between
    all running copies.  Third, if you're only routing a
    few subnets over the VPN, you probably would prefer to
    keep using your local DNS server for everything else.
 -N, --auto-nets
 :   in addition to the subnets provided on the command
    line, ask the server which subnets it thinks we should
    route, and route those automatically.  The suggestions
    are taken automatically from the server's routing
    table.
 --dns
 :   capture local DNS requests and forward to the remote DNS
    server.
 --python
 :   specify the name/path of the remote python interpreter. 
    The default is just `python`, which means to use the
    default python interpreter on the remote system's PATH.
 -r, --remote=*[username@]sshserver[:port]*
 :   the remote hostname and optional username and ssh
    port number to use for connecting to the remote server. 
    For example, example.com, testuser@example.com,
    testuser@example.com:2222, or example.com:2244.
 -x, --exclude=*subnet*
 :   explicitly exclude this subnet from forwarding.  The
    format of this option is the same as the `<subnets>`
    option.  To exclude more than one subnet, specify the
    `-x` option more than once.  You can say something like
    `0/0 -x 1.2.3.0/24` to forward everything except the
    local subnet over the VPN, for example.
 --exclude-from=*file*
 :   exclude the subnets specified in a file, one subnet per
    line. Useful when you have lots of subnets to exclude.
 -v, --verbose
 :   print more information about the session.  This option
    can be used more than once for increased verbosity.  By
    default, sshuttle prints only error messages.
 -e, --ssh-cmd
 :   the command to use to connect to the remote server. The
    default is just `ssh`.  Use this if your ssh client is
    in a non-standard location or you want to provide extra
    options to the ssh command, for example, `-e 'ssh -v'`.
 --seed-hosts
 :   a comma-separated list of hostnames to use to
    initialize the `--auto-hosts` scan algorithm. 
    `--auto-hosts` does things like poll local SMB servers
    for lists of local hostnames, but can speed things up
    if you use this option to give it a few names to start
    from.
 --no-latency-control
 :   sacrifice latency to improve bandwidth benchmarks. ssh
    uses really big socket buffers, which can overload the
    connection if you start doing large file transfers,
    thus making all your other sessions inside the same
    tunnel go slowly. Normally, sshuttle tries to avoid
    this problem using a "fullness check" that allows only
    a certain amount of outstanding data to be buffered at
    a time.  But on high-bandwidth links, this can leave a
    lot of your bandwidth underutilized.  It also makes
    sshuttle seem slow in bandwidth benchmarks (benchmarks
    rarely test ping latency, which is what sshuttle is
    trying to control).  This option disables the latency
    control feature, maximizing bandwidth usage.  Use at
    your own risk.
 -D, --daemon
 :   automatically fork into the background after connecting
    to the remote server.  Implies `--syslog`.
 --syslog
 :   after connecting, send all log messages to the
    `syslog`(3) service instead of stderr.  This is
    implicit if you use `--daemon`.
 --pidfile=*pidfilename*
 :   when using `--daemon`, save sshuttle's pid to
    *pidfilename*.  The default is `sshuttle.pid` in the
    current directory.
 --server
 :   (internal use only) run the sshuttle server on
    stdin/stdout.  This is what the client runs on
    the remote end.
 --firewall
 :   (internal use only) run the firewall manager.  This is
    the only part of sshuttle that must run as root.  If
    you start sshuttle as a non-root user, it will
    automatically run `sudo` or `su` to start the firewall
    manager, but the core of sshuttle still runs as a
    normal user.
 --hostwatch
 :   (internal use only) run the hostwatch daemon.  This
    process runs on the server side and collects hostnames for
    the `--auto-hosts` option.  Using this option by itself
    makes it a lot easier to debug and test the `--auto-hosts`
    feature.
 # EXAMPLES
 Test locally by proxying all local connections, without using ssh:
    $ sshuttle -v 0/0
    Starting sshuttle proxy.
    Listening on ('0.0.0.0', 12300).
    [local sudo] Password: 
    firewall manager ready.
    c : connecting to server...
     s: available routes:
     s:   192.168.42.0/24
    c : connected.
    firewall manager: starting transproxy.
    c : Accept: 192.168.42.106:50035 -> 192.168.42.121:139.
    c : Accept: 192.168.42.121:47523 -> 77.141.99.22:443.
        ...etc...
    ^C
    firewall manager: undoing changes.
    KeyboardInterrupt
    c : Keyboard interrupt: exiting.
    c : SW#8:192.168.42.121:47523: deleting
    c : SW#6:192.168.42.106:50035: deleting
 Test connection to a remote server, with automatic hostname
 and subnet guessing:
    $ sshuttle -vNHr example.org
    Starting sshuttle proxy.
    Listening on ('0.0.0.0', 12300).
    firewall manager ready.
    c : connecting to server...
     s: available routes:
     s:   77.141.99.0/24
    c : connected.
    c : seed_hosts: []
    firewall manager: starting transproxy.
    hostwatch: Found: testbox1: 1.2.3.4
    hostwatch: Found: mytest2: 5.6.7.8
    hostwatch: Found: domaincontroller: 99.1.2.3
    c : Accept: 192.168.42.121:60554 -> 77.141.99.22:22.
    ^C
    firewall manager: undoing changes.
    c : Keyboard interrupt: exiting.
    c : SW#6:192.168.42.121:60554: deleting
 # DISCUSSION
 When it starts, sshuttle creates an ssh session to the
 server specified by the `-r` option.  If `-r` is omitted,
 it will start both its client and server locally, which is
 sometimes useful for testing.
 After connecting to the remote server, sshuttle uploads its
 (python) source code to the remote end and executes it
 there.  Thus, you don't need to install sshuttle on the
 remote server, and there are never sshuttle version
 conflicts between client and server.
 Unlike most VPNs, sshuttle forwards sessions, not packets. 
 That is, it uses kernel transparent proxying (`iptables
 REDIRECT` rules on Linux, or `ipfw fwd` rules on BSD) to
 capture outgoing TCP sessions, then creates entirely
 separate TCP sessions out to the original destination at
 the other end of the tunnel.
 Packet-level forwarding (eg. using the tun/tap devices on
 Linux) seems elegant at first, but it results in
 several problems, notably the 'tcp over tcp' problem.  The
 tcp protocol depends fundamentally on packets being dropped
 in order to implement its congestion control agorithm; if
 you pass tcp packets through a tcp-based tunnel (such as
 ssh), the inner tcp packets will never be dropped, and so
 the inner tcp stream's congestion control will be
 completely broken, and performance will be terrible.  Thus,
 packet-based VPNs (such as IPsec and openvpn) cannot use
 tcp-based encrypted streams like ssh or ssl, and have to
 implement their own encryption from scratch, which is very
 complex and error prone.
 sshuttle's simplicity comes from the fact that it can
 safely use the existing ssh encrypted tunnel without
 incurring a performance penalty.  It does this by letting
 the client-side kernel manage the incoming tcp stream, and
 the server-side kernel manage the outgoing tcp stream;
 there is no need for congestion control to be shared
 between the two separate streams, so a tcp-based tunnel is
 fine.
 # BUGS
 On MacOS 10.6 (at least up to 10.6.6), your network will
 stop responding about 10 minutes after the first time you
 start sshuttle, because of a MacOS kernel bug relating to
 arp and the net.inet.ip.scopedroute sysctl.  To fix it,
 just switch your wireless off and on. Sshuttle makes the
 kernel setting it changes permanent, so this won't happen
 again, even after a reboot.
 # SEE ALSO
 `ssh`(1), `python`(1)
--- a/207
+++ b/207
@ -1,125 +1,112 @@
-                  GNU LESSER GENERAL PUBLIC LICENSE
+		  GNU LIBRARY GENERAL PUBLIC LICENSE
-                       Version 2.1, February 1999
+		       Version 2, June 1991
- Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+ Copyright (C) 1991 Free Software Foundation, Inc.
- 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+                    675 Mass Ave, Cambridge, MA 02139, USA
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.
-[This is the first released version of the Lesser GPL.  It also counts
+[This is the first released version of the library GPL.  It is
- as the successor of the GNU Library Public License, version 2, hence
+ numbered 2 because it goes with version 2 of the ordinary GPL.]
 the version number 2.1.]
-                            Preamble
+			    Preamble
  The licenses for most software are designed to take away your
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 Licenses are intended to guarantee your freedom to share and change
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-
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@ -295,31 +282,23 @@ of these things:
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    will operate properly with a modified version of the library, if
    the user installs one, as long as the modified version is
    interface-compatible with the version that the work was made with.
    c) Accompany the work with a written offer, valid for at
    least three years, to give the same user the materials
    specified in Subsection 6a, above, for a charge no more
    than the cost of performing this distribution.
-    d) If distribution of the work is made by offering access to copy
+    c) If distribution of the work is made by offering access to copy
    from a designated place, offer equivalent access to copy the above
    specified materials from the same place.
-    e) Verify that the user has already received a copy of these
+    d) Verify that the user has already received a copy of these
    materials or that you have already sent this user a copy.
  For an executable, the required form of the "work that uses the
 Library" must include any data and utility programs needed for
 reproducing the executable from it.  However, as a special exception,
-the materials to be distributed need not include anything that is
+the source code distributed need not include anything that is normally
-normally distributed (in either source or binary form) with the major
+distributed (in either source or binary form) with the major
 components (compiler, kernel, and so on) of the operating system on
 which the executable runs, unless that component itself accompanies
 the executable.
@ -368,7 +347,7 @@ Library), the recipient automatically receives a license from the
 original licensor to copy, distribute, link with or modify the Library
 subject to these terms and conditions.  You may not impose any further
 restrictions on the recipients' exercise of the rights granted herein.
-You are not responsible for enforcing compliance by third parties with
+You are not responsible for enforcing compliance by third parties to
 this License.
  11. If, as a consequence of a court judgment or allegation of patent
@ -411,7 +390,7 @@ excluded.  In such case, this License incorporates the limitation as if
 written in the body of this License.
  13. The Free Software Foundation may publish revised and/or new
-versions of the Lesser General Public License from time to time.
+versions of the Library General Public License from time to time.
 Such new versions will be similar in spirit to the present version,
 but may differ in detail to address new problems or concerns.
@ -432,7 +411,7 @@ decision will be guided by the two goals of preserving the free status
 of all derivatives of our free software and of promoting the sharing
 and reuse of software generally.
-                            NO WARRANTY
+			    NO WARRANTY
  15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
 WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
@ -455,9 +434,9 @@ FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
 SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
 DAMAGES.
-                     END OF TERMS AND CONDITIONS
+		     END OF TERMS AND CONDITIONS
-           How to Apply These Terms to Your New Libraries
+     Appendix: How to Apply These Terms to Your New Libraries
  If you develop a new library, and you want it to be of the greatest
 possible use to the public, we recommend making it free software that
@ -474,18 +453,18 @@ convey the exclusion of warranty; and each file should have at least the
    Copyright (C) <year>  <name of author>
    This library is free software; you can redistribute it and/or
-    modify it under the terms of the GNU Lesser General Public
+    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
-    version 2.1 of the License, or (at your option) any later version.
+    version 2 of the License, or (at your option) any later version.
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-    Lesser General Public License for more details.
+    Library General Public License for more details.
-    You should have received a copy of the GNU Lesser General Public
+    You should have received a copy of the GNU Library General Public
-    License along with this library; if not, write to the Free Software
+    License along with this library; if not, write to the Free
-    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 Also add information on how to contact you by electronic and paper mail.
--- a/MANIFEST.in
+++ b/MANIFEST.in
@ -1,14 +0,0 @@
 include *.txt
 include *.rst
 include *.py
 include MANIFEST.in
 include LICENSE
 include run
 include tox.ini
 exclude sshuttle/version.py
 recursive-include docs *.bat
 recursive-include docs *.py
 recursive-include docs *.rst
 recursive-include docs Makefile
 recursive-include sshuttle *.py
 recursive-exclude docs/_build *
--- a/10
+++ b/10
@ -0,0 +1,10 @@
 all:
 Makefile:
 	@
 %: FORCE
 	+./do $@
 .PHONY: FORCE
--- a/README.md
+++ b/README.md
@ -0,0 +1,189 @@
 WARNING:
 On MacOS 10.6 (at least up to 10.6.6), your network will
 stop responding about 10 minutes after the first time you
 start sshuttle, because of a MacOS kernel bug relating to
 arp and the net.inet.ip.scopedroute sysctl.  To fix it,
 just switch your wireless off and on. Sshuttle makes the
 kernel setting it changes permanent, so this won't happen
 again, even after a reboot.
 sshuttle: where transparent proxy meets VPN meets ssh
 =====================================================
 As far as I know, sshuttle is the only program that solves the following
 common case:
 - Your client machine (or router) is Linux, FreeBSD, or MacOS.
 - You have access to a remote network via ssh.
 - You don't necessarily have admin access on the remote network.
 - The remote network has no VPN, or only stupid/complex VPN
    protocols (IPsec, PPTP, etc). Or maybe you <i>are</i> the
    admin and you just got frustrated with the awful state of
    VPN tools.
 - You don't want to create an ssh port forward for every
    single host/port on the remote network.
 - You hate openssh's port forwarding because it's randomly
    slow and/or stupid.
 - You can't use openssh's PermitTunnel feature because
    it's disabled by default on openssh servers; plus it does
    TCP-over-TCP, which has terrible performance (see below).
 Prerequisites
 -------------
 - sudo, su, or logged in as root on your client machine.
   (The server doesn't need admin access.)
 - If you use Linux on your client machine:
   iptables installed on the client, including at
   least the iptables DNAT, REDIRECT, and ttl modules. 
   These are installed by default on most Linux distributions. 
   (The server doesn't need iptables and doesn't need to be
   Linux.)
 - If you use MacOS or BSD on your client machine:
   Your kernel needs to be compiled with IPFIREWALL_FORWARD
   (MacOS has this by default) and you need to have ipfw
   available. (The server doesn't need to be MacOS or BSD.)
 This is how you use it:
 -----------------------
 - <tt>git clone git://github.com/apenwarr/sshuttle</tt>
    on your client machine. You'll need root or sudo
    access, and python needs to be installed.
 - The most basic use of sshuttle looks like:
  <tt>./sshuttle -r username@sshserver 0.0.0.0/0 -vv</tt>
 - There is a shortcut for 0.0.0.0/0 for those that value
   their wrists
   <tt>./sshuttle -r username@sshserver 0/0 -vv</tt>
 - If you would also like your DNS queries to be proxied
   through the DNS server of the server you are connect to:
   <tt>./sshuttle --dns -vvr username@sshserver 0/0</tt>
   The above is probably what you want to use to prevent
   local network attacks such as Firesheep and friends.
 (You may be prompted for one or more passwords; first, the
 local password to become root using either sudo or su, and
 then the remote ssh password.  Or you might have sudo and ssh set
 up to not require passwords, in which case you won't be
 prompted at all.)
 That's it!  Now your local machine can access the remote network as if you
 were right there.  And if your "client" machine is a router, everyone on
 your local network can make connections to your remote network.
 You don't need to install sshuttle on the remote server;
 the remote server just needs to have python available. 
 sshuttle will automatically upload and run its source code
 to the remote python interpreter.
 This creates a transparent proxy server on your local machine for all IP
 addresses that match 0.0.0.0/0.  (You can use more specific IP addresses if
 you want; use any number of IP addresses or subnets to change which
 addresses get proxied.  Using 0.0.0.0/0 proxies <i>everything</i>, which is
 interesting if you don't trust the people on your local network.)
 Any TCP session you initiate to one of the proxied IP addresses will be
 captured by sshuttle and sent over an ssh session to the remote copy of
 sshuttle, which will then regenerate the connection on that end, and funnel
 the data back and forth through ssh.
 Fun, right?  A poor man's instant VPN, and you don't even have to have
 admin access on the server.
 Theory of Operation
 -------------------
 sshuttle is not exactly a VPN, and not exactly port forwarding.  It's kind
 of both, and kind of neither.
 It's like a VPN, since it can forward every port on an entire network, not
 just ports you specify.  Conveniently, it lets you use the "real" IP
 addresses of each host rather than faking port numbers on localhost.
 On the other hand, the way it *works* is more like ssh port forwarding than
 a VPN.  Normally, a VPN forwards your data one packet at a time, and
 doesn't care about individual connections; ie. it's "stateless" with respect
 to the traffic.  sshuttle is the opposite of stateless; it tracks every
 single connection.
 You could compare sshuttle to something like the old <a
 href="http://en.wikipedia.org/wiki/Slirp">Slirp</a> program, which was a
 userspace TCP/IP implementation that did something similar.  But it
 operated on a packet-by-packet basis on the client side, reassembling the
 packets on the server side.  That worked okay back in the "real live serial
 port" days, because serial ports had predictable latency and buffering.
 But you can't safely just forward TCP packets over a TCP session (like ssh),
 because TCP's performance depends fundamentally on packet loss; it
 <i>must</i> experience packet loss in order to know when to slow down!  At
 the same time, the outer TCP session (ssh, in this case) is a reliable
 transport, which means that what you forward through the tunnel <i>never</i>
 experiences packet loss.  The ssh session itself experiences packet loss, of
 course, but TCP fixes it up and ssh (and thus you) never know the
 difference.  But neither does your inner TCP session, and extremely screwy
 performance ensues.
 sshuttle assembles the TCP stream locally, multiplexes it statefully over
 an ssh session, and disassembles it back into packets at the other end.  So
 it never ends up doing TCP-over-TCP.  It's just data-over-TCP, which is
 safe.
 Useless Trivia
 --------------
 Back in 1998 (12 years ago!  Yikes!), I released the first version of <a
 href="http://alumnit.ca/wiki/?TunnelVisionReadMe">Tunnel Vision</a>, a
 semi-intelligent VPN client for Linux.  Unfortunately, I made two big mistakes: 
 I implemented the key exchange myself (oops), and I ended up doing
 TCP-over-TCP (double oops).  The resulting program worked okay - and people
 used it for years - but the performance was always a bit funny.  And nobody
 ever found any security flaws in my key exchange, either, but that doesn't
 mean anything. :)
 The same year, dcoombs and I also released Fast Forward, a proxy server
 supporting transparent proxying.  Among other things, we used it for
 automatically splitting traffic across more than one Internet connection (a
 tool we called "Double Vision").
 I was still in university at the time.  A couple years after that, one of my
 professors was working with some graduate students on the technology that
 would eventually become <a href="http://www.slipstream.com/">Slipstream
 Internet Acceleration</a>.  He asked me to do a contract for him to build an
 initial prototype of a transparent proxy server for mobile networks.  The
 idea was similar to sshuttle: if you reassemble and then disassemble the TCP
 packets, you can reduce latency and improve performance vs.  just forwarding
 the packets over a plain VPN or mobile network.  (It's unlikely that any of
 my code has persisted in the Slipstream product today, but the concept is
 still pretty cool.  I'm still horrified that people use plain TCP on
 complex mobile networks with crazily variable latency, for which it was
 never really intended.)
 That project I did for Slipstream was what first gave me the idea to merge
 the concepts of Fast Forward, Double Vision, and Tunnel Vision into a single
 program that was the best of all worlds.  And here we are, at last, 10 years
 later.  You're welcome.
 --
 Avery Pennarun <apenwarr@gmail.com>
 Mailing list:
   Subscribe by sending a message to <sshuttle+subscribe@googlegroups.com>
   List archives are at: http://groups.google.com/group/sshuttle
--- a/README.rst
+++ b/README.rst
@ -1,49 +0,0 @@
 sshuttle: where transparent proxy meets VPN meets ssh
 =====================================================
 As far as I know, sshuttle is the only program that solves the following
 common case:
 - Your client machine (or router) is Linux, FreeBSD, MacOS or Windows.
 - You have access to a remote network via ssh.
 - You don't necessarily have admin access on the remote network.
 - The remote network has no VPN, or only stupid/complex VPN
  protocols (IPsec, PPTP, etc). Or maybe you *are* the
  admin and you just got frustrated with the awful state of
  VPN tools.
 - You don't want to create an ssh port forward for every
  single host/port on the remote network.
 - You hate openssh's port forwarding because it's randomly
  slow and/or stupid.
 - You can't use openssh's PermitTunnel feature because
  it's disabled by default on openssh servers; plus it does
  TCP-over-TCP, which has `terrible performance`_.
 .. _terrible performance: https://sshuttle.readthedocs.io/en/stable/how-it-works.html
 Obtaining sshuttle
 ------------------
 Please see the documentation_.
 .. _Documentation: https://sshuttle.readthedocs.io/en/stable/installation.html
 Documentation
 -------------
 The documentation for the stable version is available at:
 https://sshuttle.readthedocs.org/
 The documentation for the latest development version is available at:
 https://sshuttle.readthedocs.org/en/latest/
 Running as a service
 --------------------
 Sshuttle can also be run as a service and configured using a config management system:
 https://medium.com/@mike.reider/using-sshuttle-as-a-service-bec2684a65fe
--- a/all.do
+++ b/all.do
@ -0,0 +1,11 @@
 exec >&2
 UI=
 [ "$(uname)" = "Darwin" ] && UI=ui-macos/all
 redo-ifchange Documentation/all version/all $UI
 echo
 echo "What now?"
 [ -z "$UI" ] || echo "- Try the MacOS GUI: open ui-macos/Sshuttle*.app"
 echo "- Run sshuttle: ./sshuttle --dns -r HOSTNAME 0/0"
 echo "- Read the README: less README.md"
 echo "- Read the man page: less Documentation/sshuttle.md"
--- a/assembler.py
+++ b/assembler.py
@ -0,0 +1,26 @@
 import sys, zlib
 z = zlib.decompressobj()
 mainmod = sys.modules[__name__]
 while 1:
    name = sys.stdin.readline().strip()
    if name:
        nbytes = int(sys.stdin.readline())
        if verbosity >= 2:
            sys.stderr.write('server: assembling %r (%d bytes)\n'
                             % (name, nbytes))
        content = z.decompress(sys.stdin.read(nbytes))
        exec compile(content, name, "exec")
        # FIXME: this crushes everything into a single module namespace,
        # then makes each of the module names point at this one. Gross.
        assert(name.endswith('.py'))
        modname = name[:-3]
        mainmod.__dict__[modname] = mainmod
    else:
        break
 verbose = verbosity
 sys.stderr.flush()
 sys.stdout.flush()
 main()
--- a/bandit.yml
+++ b/bandit.yml
@ -1,9 +0,0 @@
 exclude_dirs:
  - tests
 skips:
  - B101
  - B104
  - B404
  - B603
  - B606
  - B607
--- a/clean.do
+++ b/clean.do
@ -0,0 +1,2 @@
 redo ui-macos/clean Documentation/clean version/clean
 rm -f *~ */*~ .*~ */.*~ *.8 *.tmp */*.tmp *.pyc */*.pyc
--- a/client.py
+++ b/client.py
@ -0,0 +1,402 @@
 import struct, socket, select, errno, re, signal, time
 import compat.ssubprocess as ssubprocess
 import helpers, ssnet, ssh, ssyslog
 from ssnet import SockWrapper, Handler, Proxy, Mux, MuxWrapper
 from helpers import *
 _extra_fd = os.open('/dev/null', os.O_RDONLY)
 def got_signal(signum, frame):
    log('exiting on signal %d\n' % signum)
    sys.exit(1)
 _pidname = None
 def check_daemon(pidfile):
    global _pidname
    _pidname = os.path.abspath(pidfile)
    try:
        oldpid = open(_pidname).read(1024)
    except IOError, e:
        if e.errno == errno.ENOENT:
            return  # no pidfile, ok
        else:
            raise Fatal("can't read %s: %s" % (_pidname, e))
    if not oldpid:
        os.unlink(_pidname)
        return  # invalid pidfile, ok
    oldpid = int(oldpid.strip() or 0)
    if oldpid <= 0:
        os.unlink(_pidname)
        return  # invalid pidfile, ok
    try:
        os.kill(oldpid, 0)
    except OSError, e:
        if e.errno == errno.ESRCH:
            os.unlink(_pidname)
            return  # outdated pidfile, ok
        elif e.errno == errno.EPERM:
            pass
        else:
            raise
    raise Fatal("%s: sshuttle is already running (pid=%d)"
                % (_pidname, oldpid))
 def daemonize():
    if os.fork():
        os._exit(0)
    os.setsid()
    if os.fork():
        os._exit(0)
    outfd = os.open(_pidname, os.O_WRONLY|os.O_CREAT|os.O_EXCL, 0666)
    try:
        os.write(outfd, '%d\n' % os.getpid())
    finally:
        os.close(outfd)
    os.chdir("/")
    # Normal exit when killed, or try/finally won't work and the pidfile won't
    # be deleted.
    signal.signal(signal.SIGTERM, got_signal)
    si = open('/dev/null', 'r+')
    os.dup2(si.fileno(), 0)
    os.dup2(si.fileno(), 1)
    si.close()
    ssyslog.stderr_to_syslog()
 def daemon_cleanup():
    try:
        os.unlink(_pidname)
    except OSError, e:
        if e.errno == errno.ENOENT:
            pass
        else:
            raise
 def original_dst(sock):
    try:
        SO_ORIGINAL_DST = 80
        SOCKADDR_MIN = 16
        sockaddr_in = sock.getsockopt(socket.SOL_IP,
                                      SO_ORIGINAL_DST, SOCKADDR_MIN)
        (proto, port, a,b,c,d) = struct.unpack('!HHBBBB', sockaddr_in[:8])
        assert(socket.htons(proto) == socket.AF_INET)
        ip = '%d.%d.%d.%d' % (a,b,c,d)
        return (ip,port)
    except socket.error, e:
        if e.args[0] == errno.ENOPROTOOPT:
            return sock.getsockname()
        raise
 class FirewallClient:
    def __init__(self, port, subnets_include, subnets_exclude, dnsport):
        self.port = port
        self.auto_nets = []
        self.subnets_include = subnets_include
        self.subnets_exclude = subnets_exclude
        self.dnsport = dnsport
        argvbase = ([sys.argv[1], sys.argv[0], sys.argv[1]] +
                    ['-v'] * (helpers.verbose or 0) +
                    ['--firewall', str(port), str(dnsport)])
        if ssyslog._p:
            argvbase += ['--syslog']
        argv_tries = [
            ['sudo', '-p', '[local sudo] Password: '] + argvbase,
            ['su', '-c', ' '.join(argvbase)],
            argvbase
        ]
        # we can't use stdin/stdout=subprocess.PIPE here, as we normally would,
        # because stupid Linux 'su' requires that stdin be attached to a tty.
        # Instead, attach a *bidirectional* socket to its stdout, and use
        # that for talking in both directions.
        (s1,s2) = socket.socketpair()
        def setup():
            # run in the child process
            s2.close()
        e = None
        if os.getuid() == 0:
            argv_tries = argv_tries[-1:]  # last entry only
        for argv in argv_tries:
            try:
                if argv[0] == 'su':
                    sys.stderr.write('[local su] ')
                self.p = ssubprocess.Popen(argv, stdout=s1, preexec_fn=setup)
                e = None
                break
            except OSError, e:
                pass
        self.argv = argv
        s1.close()
        self.pfile = s2.makefile('wb+')
        if e:
            log('Spawning firewall manager: %r\n' % self.argv)
            raise Fatal(e)
        line = self.pfile.readline()
        self.check()
        if line != 'READY\n':
            raise Fatal('%r expected READY, got %r' % (self.argv, line))
    def check(self):
        rv = self.p.poll()
        if rv:
            raise Fatal('%r returned %d' % (self.argv, rv))
    def start(self):
        self.pfile.write('ROUTES\n')
        for (ip,width) in self.subnets_include+self.auto_nets:
            self.pfile.write('%d,0,%s\n' % (width, ip))
        for (ip,width) in self.subnets_exclude:
            self.pfile.write('%d,1,%s\n' % (width, ip))
        self.pfile.write('GO\n')
        self.pfile.flush()
        line = self.pfile.readline()
        self.check()
        if line != 'STARTED\n':
            raise Fatal('%r expected STARTED, got %r' % (self.argv, line))
    def sethostip(self, hostname, ip):
        assert(not re.search(r'[^-\w]', hostname))
        assert(not re.search(r'[^0-9.]', ip))
        self.pfile.write('HOST %s,%s\n' % (hostname, ip))
        self.pfile.flush()
    def done(self):
        self.pfile.close()
        rv = self.p.wait()
        if rv == EXITCODE_NEEDS_REBOOT:
            raise FatalNeedsReboot()
        elif rv:
            raise Fatal('cleanup: %r returned %d' % (self.argv, rv))
 def onaccept(listener, mux, handlers):
    global _extra_fd
    try:
        sock,srcip = listener.accept()
    except socket.error, e:
        if e.args[0] in [errno.EMFILE, errno.ENFILE]:
            debug1('Rejected incoming connection: too many open files!\n')
            # free up an fd so we can eat the connection
            os.close(_extra_fd)
            try:
                sock,srcip = listener.accept()
                sock.close()
            finally:
                _extra_fd = os.open('/dev/null', os.O_RDONLY)
            return
        else:
            raise
    dstip = original_dst(sock)
    debug1('Accept: %s:%r -> %s:%r.\n' % (srcip[0],srcip[1],
                                          dstip[0],dstip[1]))
    if dstip[1] == listener.getsockname()[1] and islocal(dstip[0]):
        debug1("-- ignored: that's my address!\n")
        sock.close()
        return
    chan = mux.next_channel()
    if not chan:
        log('warning: too many open channels.  Discarded connection.\n')
        sock.close()
        return
    mux.send(chan, ssnet.CMD_CONNECT, '%s,%s' % dstip)
    outwrap = MuxWrapper(mux, chan)
    handlers.append(Proxy(SockWrapper(sock, sock), outwrap))
 dnsreqs = {}
 def dns_done(chan, data):
    peer,sock,timeout = dnsreqs.get(chan) or (None,None,None)
    debug3('dns_done: channel=%r peer=%r\n' % (chan, peer))
    if peer:
        del dnsreqs[chan]
        debug3('doing sendto %r\n' % (peer,))
        sock.sendto(data, peer)
 def ondns(listener, mux, handlers):
    pkt,peer = listener.recvfrom(4096)
    now = time.time()
    if pkt:
        debug1('DNS request from %r: %d bytes\n' % (peer, len(pkt)))
        chan = mux.next_channel()
        dnsreqs[chan] = peer,listener,now+30
        mux.send(chan, ssnet.CMD_DNS_REQ, pkt)
        mux.channels[chan] = lambda cmd,data: dns_done(chan,data)
    for chan,(peer,sock,timeout) in dnsreqs.items():
        if timeout < now:
            del dnsreqs[chan]
    debug3('Remaining DNS requests: %d\n' % len(dnsreqs))
 def _main(listener, fw, ssh_cmd, remotename, python, latency_control,
          dnslistener, seed_hosts, auto_nets,
          syslog, daemon):
    handlers = []
    if helpers.verbose >= 1:
        helpers.logprefix = 'c : '
    else:
        helpers.logprefix = 'client: '
    debug1('connecting to server...\n')
    try:
        (serverproc, serversock) = ssh.connect(ssh_cmd, remotename, python,
                        stderr=ssyslog._p and ssyslog._p.stdin,
                        options=dict(latency_control=latency_control))
    except socket.error, e:
        if e.args[0] == errno.EPIPE:
            raise Fatal("failed to establish ssh session (1)")
        else:
            raise
    mux = Mux(serversock, serversock)
    handlers.append(mux)
    expected = 'SSHUTTLE0001'
    try:
        v = 'x'
        while v and v != '\0':
            v = serversock.recv(1)
        v = 'x'
        while v and v != '\0':
            v = serversock.recv(1)
        initstring = serversock.recv(len(expected))
    except socket.error, e:
        if e.args[0] == errno.ECONNRESET:
            raise Fatal("failed to establish ssh session (2)")
        else:
            raise
    rv = serverproc.poll()
    if rv:
        raise Fatal('server died with error code %d' % rv)
    if initstring != expected:
        raise Fatal('expected server init string %r; got %r'
                        % (expected, initstring))
    debug1('connected.\n')
    print 'Connected.'
    sys.stdout.flush()
    if daemon:
        daemonize()
        log('daemonizing (%s).\n' % _pidname)
    elif syslog:
        debug1('switching to syslog.\n')
        ssyslog.stderr_to_syslog()
    def onroutes(routestr):
        if auto_nets:
            for line in routestr.strip().split('\n'):
                (ip,width) = line.split(',', 1)
                fw.auto_nets.append((ip,int(width)))
        # we definitely want to do this *after* starting ssh, or we might end
        # up intercepting the ssh connection!
        #
        # Moreover, now that we have the --auto-nets option, we have to wait
        # for the server to send us that message anyway.  Even if we haven't
        # set --auto-nets, we might as well wait for the message first, then
        # ignore its contents.
        mux.got_routes = None
        fw.start()
    mux.got_routes = onroutes
    def onhostlist(hostlist):
        debug2('got host list: %r\n' % hostlist)
        for line in hostlist.strip().split():
            if line:
                name,ip = line.split(',', 1)
                fw.sethostip(name, ip)
    mux.got_host_list = onhostlist
    handlers.append(Handler([listener], lambda: onaccept(listener, mux, handlers)))
    if dnslistener:
        handlers.append(Handler([dnslistener], lambda: ondns(dnslistener, mux, handlers)))
    if seed_hosts != None:
        debug1('seed_hosts: %r\n' % seed_hosts)
        mux.send(0, ssnet.CMD_HOST_REQ, '\n'.join(seed_hosts))
    while 1:
        rv = serverproc.poll()
        if rv:
            raise Fatal('server died with error code %d' % rv)
        ssnet.runonce(handlers, mux)
        if latency_control:
            mux.check_fullness()
        mux.callback()
 def main(listenip, ssh_cmd, remotename, python, latency_control, dns,
         seed_hosts, auto_nets,
         subnets_include, subnets_exclude, syslog, daemon, pidfile):
    if syslog:
        ssyslog.start_syslog()
    if daemon:
        try:
            check_daemon(pidfile)
        except Fatal, e:
            log("%s\n" % e)
            return 5
    debug1('Starting sshuttle proxy.\n')
    if listenip[1]:
        ports = [listenip[1]]
    else:
        ports = xrange(12300,9000,-1)
    last_e = None
    bound = False
    debug2('Binding:')
    for port in ports:
        debug2(' %d' % port)
        listener = socket.socket()
        listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        dnslistener = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        dnslistener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        try:
            listener.bind((listenip[0], port))
            dnslistener.bind((listenip[0], port))
            bound = True
            break
        except socket.error, e:
            last_e = e
    debug2('\n')
    if not bound:
        assert(last_e)
        raise last_e
    listener.listen(10)
    listenip = listener.getsockname()
    debug1('Listening on %r.\n' % (listenip,))
    if dns:
        dnsip = dnslistener.getsockname()
        debug1('DNS listening on %r.\n' % (dnsip,))
        dnsport = dnsip[1]
    else:
        dnsport = 0
        dnslistener = None
    fw = FirewallClient(listenip[1], subnets_include, subnets_exclude, dnsport)
    try:
        return _main(listener, fw, ssh_cmd, remotename,
                     python, latency_control, dnslistener,
                     seed_hosts, auto_nets, syslog, daemon)
    finally:
        try:
            if daemon:
                # it's not our child anymore; can't waitpid
                fw.p.returncode = 0
            fw.done()
        finally:
            if daemon:
                daemon_cleanup()
--- a/compat/init.py
+++ b/compat/init.py
--- a/compat/ssubprocess.py
+++ b/compat/ssubprocess.py
--- a/default.8.do
+++ b/default.8.do
@ -0,0 +1,7 @@
 exec >&2
 if pandoc </dev/null 2>/dev/null; then
 	pandoc -s -r markdown -w man -o $3 $2.md
 else
 	echo "Warning: pandoc not installed; can't generate manpages."
 	redo-always
 fi
--- a/175
+++ b/175
@ -0,0 +1,175 @@
 #!/bin/sh
 #
 # A minimal alternative to djb redo that doesn't support incremental builds.
 # For the full version, visit http://github.com/apenwarr/redo
 #
 # The author disclaims copyright to this source file and hereby places it in
 # the public domain. (2010 12 14)
 #
 # By default, no output coloring.
 green=""
 bold=""
 plain=""
 if [ -n "$TERM" -a "$TERM" != "dumb" ] && tty <&2 >/dev/null 2>&1; then
 	green="$(printf '\033[32m')"
 	bold="$(printf '\033[1m')"
 	plain="$(printf '\033[m')"
 fi
 _dirsplit()
 {
 	base=${1##*/}
 	dir=${1%$base}
 }
 dirname()
 (
 	_dirsplit "$1"
 	dir=${dir%/}
 	echo "${dir:-.}"
 )
 _dirsplit "$0"
 export REDO=$(cd "${dir:-.}" && echo "$PWD/$base")
 DO_TOP=
 if [ -z "$DO_BUILT" ]; then
 	DO_TOP=1
 	[ -n "$*" ] || set all  # only toplevel redo has a default target
 	export DO_BUILT=$PWD/.do_built
 	: >>"$DO_BUILT"
 	echo "Removing previously built files..." >&2
 	sort -u "$DO_BUILT" | tee "$DO_BUILT.new" |
 	while read f; do printf "%s\0%s.did\0" "$f" "$f"; done |
 	xargs -0 rm -f 2>/dev/null
 	mv "$DO_BUILT.new" "$DO_BUILT"
 	DO_PATH=$DO_BUILT.dir
 	export PATH=$DO_PATH:$PATH
 	rm -rf "$DO_PATH"
 	mkdir "$DO_PATH"
 	for d in redo redo-ifchange; do
 		ln -s "$REDO" "$DO_PATH/$d";
 	done
 	[ -e /bin/true ] && TRUE=/bin/true || TRUE=/usr/bin/true
 	for d in redo-ifcreate redo-stamp redo-always; do 
 		ln -s $TRUE "$DO_PATH/$d";
 	done
 fi
 _find_dofile_pwd()
 {
 	dofile=default.$1.do
 	while :; do
 		dofile=default.${dofile#default.*.}
 		[ -e "$dofile" -o "$dofile" = default.do ] && break
 	done
 	ext=${dofile#default}
 	ext=${ext%.do}
 	base=${1%$ext}
 }
 _find_dofile()
 {
 	local prefix=
 	while :; do
 		_find_dofile_pwd "$1"
 		[ -e "$dofile" ] && break
 		[ "$PWD" = "/" ] && break
 		target=${PWD##*/}/$target
 		tmp=${PWD##*/}/$tmp
 		prefix=${PWD##*/}/$prefix
 		cd ..
 	done
 	base=$prefix$base
 }
 _run_dofile()
 {
 	export DO_DEPTH="$DO_DEPTH  "
 	export REDO_TARGET=$PWD/$target
 	local line1
 	set -e
 	read line1 <"$PWD/$dofile"
 	cmd=${line1#"#!/"}
 	if [ "$cmd" != "$line1" ]; then
 		/$cmd "$PWD/$dofile" "$@" >"$tmp.tmp2"
 	else
 		:; . "$PWD/$dofile" >"$tmp.tmp2"
 	fi
 }
 _do()
 {
 	local dir=$1 target=$2 tmp=$3
 	if [ ! -e "$target" ] || [ -d "$target" -a ! -e "$target.did" ]; then
 		printf '%sdo  %s%s%s%s\n' \
 			"$green" "$DO_DEPTH" "$bold" "$dir$target" "$plain" >&2
 		echo "$PWD/$target" >>"$DO_BUILT"
 		dofile=$target.do
 		base=$target
 		ext=
 		[ -e "$target.do" ] || _find_dofile "$target"
 		if [ ! -e "$dofile" ]; then
 			echo "do: $target: no .do file" >&2
 			return 1
 		fi
 		[ ! -e "$DO_BUILT" ] || [ ! -d "$(dirname "$target")" ] ||
 		: >>"$target.did"
 		( _run_dofile "$target" "$base" "$tmp.tmp" )
 		rv=$?
 		if [ $rv != 0 ]; then
 			printf "do: %s%s\n" "$DO_DEPTH" \
 				"$dir$target: got exit code $rv" >&2
 			rm -f "$tmp.tmp" "$tmp.tmp2"
 			return $rv
 		fi
 		mv "$tmp.tmp" "$target" 2>/dev/null ||
 		! test -s "$tmp.tmp2" ||
 		mv "$tmp.tmp2" "$target" 2>/dev/null
 		rm -f "$tmp.tmp2"
 	else
 		echo "do  $DO_DEPTH$target exists." >&2
 	fi
 }
 # Make corrections for directories that don't actually exist yet.
 _dir_shovel()
 {
 	local dir base
 	xdir=$1 xbase=$2 xbasetmp=$2
 	while [ ! -d "$xdir" -a -n "$xdir" ]; do
 		_dirsplit "${xdir%/}"
 		xbasetmp=${base}__$xbase
 		xdir=$dir xbase=$base/$xbase
 		echo "xbasetmp='$xbasetmp'" >&2
 	done
 }
 redo()
 {
 	for i in "$@"; do
 		_dirsplit "$i"
 		_dir_shovel "$dir" "$base"
 		dir=$xdir base=$xbase basetmp=$xbasetmp
 		( cd "$dir" && _do "$dir" "$base" "$basetmp" ) || return 1
 	done
 }
 set -e
 redo "$@"
 if [ -n "$DO_TOP" ]; then
 	echo "Removing stamp files..." >&2
 	[ ! -e "$DO_BUILT" ] ||
 	while read f; do printf "%s.did\0" "$f"; done <"$DO_BUILT" |
 	xargs -0 rm -f 2>/dev/null
 fi
--- a/docs/Makefile
+++ b/docs/Makefile
@ -1,177 +0,0 @@
 # Makefile for Sphinx documentation
 #
 # You can set these variables from the command line.
 SPHINXOPTS    =
 SPHINXBUILD   = sphinx-build
 PAPER         =
 BUILDDIR      = _build
 # User-friendly check for sphinx-build
 ifeq ($(shell which $(SPHINXBUILD) >/dev/null 2>&1; echo $$?), 1)
 $(error The '$(SPHINXBUILD)' command was not found. Make sure you have Sphinx installed, then set the SPHINXBUILD environment variable to point to the full path of the '$(SPHINXBUILD)' executable. Alternatively you can add the directory with the executable to your PATH. If you don't have Sphinx installed, grab it from http://sphinx-doc.org/)
 endif
 # Internal variables.
 PAPEROPT_a4     = -D latex_paper_size=a4
 PAPEROPT_letter = -D latex_paper_size=letter
 ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
 # the i18n builder cannot share the environment and doctrees with the others
 I18NSPHINXOPTS  = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) .
 .PHONY: help clean html dirhtml singlehtml pickle json htmlhelp qthelp devhelp epub latex latexpdf text man changes linkcheck doctest gettext
 help:
 	@echo "Please use \`make <target>' where <target> is one of"
 	@echo "  html       to make standalone HTML files"
 	@echo "  dirhtml    to make HTML files named index.html in directories"
 	@echo "  singlehtml to make a single large HTML file"
 	@echo "  pickle     to make pickle files"
 	@echo "  json       to make JSON files"
 	@echo "  htmlhelp   to make HTML files and a HTML help project"
 	@echo "  qthelp     to make HTML files and a qthelp project"
 	@echo "  devhelp    to make HTML files and a Devhelp project"
 	@echo "  epub       to make an epub"
 	@echo "  latex      to make LaTeX files, you can set PAPER=a4 or PAPER=letter"
 	@echo "  latexpdf   to make LaTeX files and run them through pdflatex"
 	@echo "  latexpdfja to make LaTeX files and run them through platex/dvipdfmx"
 	@echo "  text       to make text files"
 	@echo "  man        to make manual pages"
 	@echo "  texinfo    to make Texinfo files"
 	@echo "  info       to make Texinfo files and run them through makeinfo"
 	@echo "  gettext    to make PO message catalogs"
 	@echo "  changes    to make an overview of all changed/added/deprecated items"
 	@echo "  xml        to make Docutils-native XML files"
 	@echo "  pseudoxml  to make pseudoxml-XML files for display purposes"
 	@echo "  linkcheck  to check all external links for integrity"
 	@echo "  doctest    to run all doctests embedded in the documentation (if enabled)"
 clean:
 	rm -rf $(BUILDDIR)/*
 html:
 	$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html
 	@echo
 	@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."
 dirhtml:
 	$(SPHINXBUILD) -b dirhtml $(ALLSPHINXOPTS) $(BUILDDIR)/dirhtml
 	@echo
 	@echo "Build finished. The HTML pages are in $(BUILDDIR)/dirhtml."
 singlehtml:
 	$(SPHINXBUILD) -b singlehtml $(ALLSPHINXOPTS) $(BUILDDIR)/singlehtml
 	@echo
 	@echo "Build finished. The HTML page is in $(BUILDDIR)/singlehtml."
 pickle:
 	$(SPHINXBUILD) -b pickle $(ALLSPHINXOPTS) $(BUILDDIR)/pickle
 	@echo
 	@echo "Build finished; now you can process the pickle files."
 json:
 	$(SPHINXBUILD) -b json $(ALLSPHINXOPTS) $(BUILDDIR)/json
 	@echo
 	@echo "Build finished; now you can process the JSON files."
 htmlhelp:
 	$(SPHINXBUILD) -b htmlhelp $(ALLSPHINXOPTS) $(BUILDDIR)/htmlhelp
 	@echo
 	@echo "Build finished; now you can run HTML Help Workshop with the" \
 	      ".hhp project file in $(BUILDDIR)/htmlhelp."
 qthelp:
 	$(SPHINXBUILD) -b qthelp $(ALLSPHINXOPTS) $(BUILDDIR)/qthelp
 	@echo
 	@echo "Build finished; now you can run "qcollectiongenerator" with the" \
 	      ".qhcp project file in $(BUILDDIR)/qthelp, like this:"
 	@echo "# qcollectiongenerator $(BUILDDIR)/qthelp/sshuttle.qhcp"
 	@echo "To view the help file:"
 	@echo "# assistant -collectionFile $(BUILDDIR)/qthelp/sshuttle.qhc"
 devhelp:
 	$(SPHINXBUILD) -b devhelp $(ALLSPHINXOPTS) $(BUILDDIR)/devhelp
 	@echo
 	@echo "Build finished."
 	@echo "To view the help file:"
 	@echo "# mkdir -p $$HOME/.local/share/devhelp/sshuttle"
 	@echo "# ln -s $(BUILDDIR)/devhelp $$HOME/.local/share/devhelp/sshuttle"
 	@echo "# devhelp"
 epub:
 	$(SPHINXBUILD) -b epub $(ALLSPHINXOPTS) $(BUILDDIR)/epub
 	@echo
 	@echo "Build finished. The epub file is in $(BUILDDIR)/epub."
 latex:
 	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
 	@echo
 	@echo "Build finished; the LaTeX files are in $(BUILDDIR)/latex."
 	@echo "Run \`make' in that directory to run these through (pdf)latex" \
 	      "(use \`make latexpdf' here to do that automatically)."
 latexpdf:
 	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
 	@echo "Running LaTeX files through pdflatex..."
 	$(MAKE) -C $(BUILDDIR)/latex all-pdf
 	@echo "pdflatex finished; the PDF files are in $(BUILDDIR)/latex."
 latexpdfja:
 	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
 	@echo "Running LaTeX files through platex and dvipdfmx..."
 	$(MAKE) -C $(BUILDDIR)/latex all-pdf-ja
 	@echo "pdflatex finished; the PDF files are in $(BUILDDIR)/latex."
 text:
 	$(SPHINXBUILD) -b text $(ALLSPHINXOPTS) $(BUILDDIR)/text
 	@echo
 	@echo "Build finished. The text files are in $(BUILDDIR)/text."
 man:
 	$(SPHINXBUILD) -b man $(ALLSPHINXOPTS) $(BUILDDIR)/man
 	@echo
 	@echo "Build finished. The manual pages are in $(BUILDDIR)/man."
 texinfo:
 	$(SPHINXBUILD) -b texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
 	@echo
 	@echo "Build finished. The Texinfo files are in $(BUILDDIR)/texinfo."
 	@echo "Run \`make' in that directory to run these through makeinfo" \
 	      "(use \`make info' here to do that automatically)."
 info:
 	$(SPHINXBUILD) -b texinfo $(ALLSPHINXOPTS) $(BUILDDIR)/texinfo
 	@echo "Running Texinfo files through makeinfo..."
 	make -C $(BUILDDIR)/texinfo info
 	@echo "makeinfo finished; the Info files are in $(BUILDDIR)/texinfo."
 gettext:
 	$(SPHINXBUILD) -b gettext $(I18NSPHINXOPTS) $(BUILDDIR)/locale
 	@echo
 	@echo "Build finished. The message catalogs are in $(BUILDDIR)/locale."
 changes:
 	$(SPHINXBUILD) -b changes $(ALLSPHINXOPTS) $(BUILDDIR)/changes
 	@echo
 	@echo "The overview file is in $(BUILDDIR)/changes."
 linkcheck:
 	$(SPHINXBUILD) -b linkcheck $(ALLSPHINXOPTS) $(BUILDDIR)/linkcheck
 	@echo
 	@echo "Link check complete; look for any errors in the above output " \
 	      "or in $(BUILDDIR)/linkcheck/output.txt."
 doctest:
 	$(SPHINXBUILD) -b doctest $(ALLSPHINXOPTS) $(BUILDDIR)/doctest
 	@echo "Testing of doctests in the sources finished, look at the " \
 	      "results in $(BUILDDIR)/doctest/output.txt."
 xml:
 	$(SPHINXBUILD) -b xml $(ALLSPHINXOPTS) $(BUILDDIR)/xml
 	@echo
 	@echo "Build finished. The XML files are in $(BUILDDIR)/xml."
 pseudoxml:
 	$(SPHINXBUILD) -b pseudoxml $(ALLSPHINXOPTS) $(BUILDDIR)/pseudoxml
 	@echo
 	@echo "Build finished. The pseudo-XML files are in $(BUILDDIR)/pseudoxml."
--- a/docs/changes.rst
+++ b/docs/changes.rst
@ -1 +0,0 @@
 .. include:: ../CHANGES.rst
--- a/docs/chromeos.rst
+++ b/docs/chromeos.rst
@ -1,11 +0,0 @@
 Google ChromeOS
 ===============
 Currently there is no built in support for running sshuttle directly on
 Google ChromeOS/Chromebooks.
 What we can really do is to create a Linux VM with Crostini.  In the default
 stretch/Debian 9 VM, you can then install sshuttle as on any Linux box and
 it just works, as do xterms and ssvncviewer etc.
 https://www.reddit.com/r/Crostini/wiki/getstarted/crostini-setup-guide
--- a/docs/conf.py
+++ b/docs/conf.py
@ -1,261 +0,0 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 #
 # sshuttle documentation build configuration file, created by
 # sphinx-quickstart on Sun Jan 17 12:13:47 2016.
 #
 # This file is execfile()d with the current directory set to its
 # containing dir.
 #
 # Note that not all possible configuration values are present in this
 # autogenerated file.
 #
 # All configuration values have a default; values that are commented out
 # serve to show the default.
 import sys
 import os
 sys.path.insert(0, os.path.abspath('..'))
 import sshuttle  # NOQA
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
 # documentation root, use os.path.abspath to make it absolute, like shown here.
 # sys.path.insert(0, os.path.abspath('.'))
 # -- General configuration ------------------------------------------------
 # If your documentation needs a minimal Sphinx version, state it here.
 # needs_sphinx = '1.0'
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
 extensions = [
    'sphinx.ext.todo',
 ]
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']
 # The suffix of source filenames.
 source_suffix = '.rst'
 # The encoding of source files.
 # source_encoding = 'utf-8-sig'
 # The master toctree document.
 master_doc = 'index'
 # General information about the project.
 project = 'sshuttle'
 copyright = '2016, Brian May'
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the
 # built documents.
 #
 # The full version, including alpha/beta/rc tags.
 release = sshuttle.__version__
 # The short X.Y version.
 version = '.'.join(release.split('.')[:2])
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
 # language = None
 # There are two options for replacing |today|: either, you set today to some
 # non-false value, then it is used:
 # today = ''
 # Else, today_fmt is used as the format for a strftime call.
 # today_fmt = '%B %d, %Y'
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.
 exclude_patterns = ['_build']
 # The reST default role (used for this markup: `text`) to use for all
 # documents.
 # default_role = None
 # If true, '()' will be appended to :func: etc. cross-reference text.
 # add_function_parentheses = True
 # If true, the current module name will be prepended to all description
 # unit titles (such as .. function::).
 # add_module_names = True
 # If true, sectionauthor and moduleauthor directives will be shown in the
 # output. They are ignored by default.
 # show_authors = False
 # The name of the Pygments (syntax highlighting) style to use.
 pygments_style = 'sphinx'
 # A list of ignored prefixes for module index sorting.
 # modindex_common_prefix = []
 # If true, keep warnings as "system message" paragraphs in the built documents.
 # keep_warnings = False
 # -- Options for HTML output ----------------------------------------------
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
 html_theme = 'furo'
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
 # documentation.
 # html_theme_options = {}
 # Add any paths that contain custom themes here, relative to this directory.
 # html_theme_path = []
 # The name for this set of Sphinx documents.  If None, it defaults to
 # "<project> v<release> documentation".
 # html_title = None
 # A shorter title for the navigation bar.  Default is the same as html_title.
 # html_short_title = None
 # The name of an image file (relative to this directory) to place at the top
 # of the sidebar.
 # html_logo = None
 # The name of an image file (within the static path) to use as favicon of the
 # docs.  This file should be a Windows icon file (.ico) being 16x16 or 32x32
 # pixels large.
 # html_favicon = None
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
 html_static_path = ['_static']
 # Add any extra paths that contain custom files (such as robots.txt or
 # .htaccess) here, relative to this directory. These files are copied
 # directly to the root of the documentation.
 # html_extra_path = []
 # If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
 # using the given strftime format.
 # html_last_updated_fmt = '%b %d, %Y'
 # If true, SmartyPants will be used to convert quotes and dashes to
 # typographically correct entities.
 # html_use_smartypants = True
 # Custom sidebar templates, maps document names to template names.
 # html_sidebars = {}
 # Additional templates that should be rendered to pages, maps page names to
 # template names.
 # html_additional_pages = {}
 # If false, no module index is generated.
 # html_domain_indices = True
 # If false, no index is generated.
 # html_use_index = True
 # If true, the index is split into individual pages for each letter.
 # html_split_index = False
 # If true, links to the reST sources are added to the pages.
 # html_show_sourcelink = True
 # If true, "Created using Sphinx" is shown in the HTML footer. Default is True.
 # html_show_sphinx = True
 # If true, "(C) Copyright ..." is shown in the HTML footer. Default is True.
 # html_show_copyright = True
 # If true, an OpenSearch description file will be output, and all pages will
 # contain a <link> tag referring to it.  The value of this option must be the
 # base URL from which the finished HTML is served.
 # html_use_opensearch = ''
 # This is the file name suffix for HTML files (e.g. ".xhtml").
 # html_file_suffix = None
 # Output file base name for HTML help builder.
 htmlhelp_basename = 'sshuttledoc'
 # -- Options for LaTeX output ---------------------------------------------
 latex_elements = {
    # The paper size ('letterpaper' or 'a4paper').
    # 'papersize': 'letterpaper',
    # The font size ('10pt', '11pt' or '12pt').
    # 'pointsize': '10pt',
    # Additional stuff for the LaTeX preamble.
    # 'preamble': '',
 }
 # Grouping the document tree into LaTeX files. List of tuples
 # (source start file, target name, title,
 #  author, documentclass [howto, manual, or own class]).
 latex_documents = [
    ('index', 'sshuttle.tex', 'sshuttle documentation', 'Brian May', 'manual'),
 ]
 # The name of an image file (relative to this directory) to place at the top of
 # the title page.
 # latex_logo = None
 # For "manual" documents, if this is true, then toplevel headings are parts,
 # not chapters.
 # latex_use_parts = False
 # If true, show page references after internal links.
 # latex_show_pagerefs = False
 # If true, show URL addresses after external links.
 # latex_show_urls = False
 # Documents to append as an appendix to all manuals.
 # latex_appendices = []
 # If false, no module index is generated.
 # latex_domain_indices = True
 # -- Options for manual page output ---------------------------------------
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
 man_pages = [
    ('manpage', 'sshuttle', 'sshuttle documentation', ['Brian May'], 1)
 ]
 # If true, show URL addresses after external links.
 # man_show_urls = False
 # -- Options for Texinfo output -------------------------------------------
 # Grouping the document tree into Texinfo files. List of tuples
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
    ('index', 'sshuttle', 'sshuttle documentation',
     'Brian May', 'sshuttle', 'A transparent proxy-based VPN using ssh',
     'Miscellaneous'),
 ]
 # Documents to append as an appendix to all manuals.
 # texinfo_appendices = []
 # If false, no module index is generated.
 # texinfo_domain_indices = True
 # How to display URL addresses: 'footnote', 'no', or 'inline'.
 # texinfo_show_urls = 'footnote'
 # If true, do not generate a @detailmenu in the "Top" node's menu.
 # texinfo_no_detailmenu = False
--- a/docs/how-it-works.rst
+++ b/docs/how-it-works.rst
@ -1,36 +0,0 @@
 How it works
 ============
 sshuttle is not exactly a VPN, and not exactly port forwarding.  It's kind
 of both, and kind of neither.
 It's like a VPN, since it can forward every port on an entire network, not
 just ports you specify.  Conveniently, it lets you use the "real" IP
 addresses of each host rather than faking port numbers on localhost.
 On the other hand, the way it *works* is more like ssh port forwarding than
 a VPN.  Normally, a VPN forwards your data one packet at a time, and
 doesn't care about individual connections; ie. it's "stateless" with respect
 to the traffic.  sshuttle is the opposite of stateless; it tracks every
 single connection.
 You could compare sshuttle to something like the old `Slirp
 <http://en.wikipedia.org/wiki/Slirp>`_ program, which was a userspace TCP/IP
 implementation that did something similar.  But it operated on a
 packet-by-packet basis on the client side, reassembling the packets on the
 server side.  That worked okay back in the "real live serial port" days,
 because serial ports had predictable latency and buffering.
 But you can't safely just forward TCP packets over a TCP session (like ssh),
 because TCP's performance depends fundamentally on packet loss; it
 *must* experience packet loss in order to know when to slow down!  At
 the same time, the outer TCP session (ssh, in this case) is a reliable
 transport, which means that what you forward through the tunnel *never*
 experiences packet loss.  The ssh session itself experiences packet loss, of
 course, but TCP fixes it up and ssh (and thus you) never know the
 difference.  But neither does your inner TCP session, and extremely screwy
 performance ensues.
 sshuttle assembles the TCP stream locally, multiplexes it statefully over
 an ssh session, and disassembles it back into packets at the other end.  So
 it never ends up doing TCP-over-TCP.  It's just data-over-TCP, which is
 safe.
--- a/docs/index.rst
+++ b/docs/index.rst
@ -1,28 +0,0 @@
 sshuttle: where transparent proxy meets VPN meets ssh
 =====================================================
 :Date: |today|
 :Version: |version|
 Contents:
 .. toctree::
   :maxdepth: 2
   overview
   requirements
   installation
   usage
   platform
   Man Page <manpage>
   how-it-works
   support
   trivia
   changes
 Indices and tables
 ==================
 * :ref:`genindex`
 * :ref:`search`
--- a/docs/installation.rst
+++ b/docs/installation.rst
@ -1,84 +0,0 @@
 Installation
 ============
 - Ubuntu 16.04 or later::
      apt-get install sshuttle
 - Debian stretch or later::
      apt-get install sshuttle
 - Arch Linux::
      pacman -S sshuttle
 - Fedora::
      dnf install sshuttle
 - openSUSE::
      zypper in sshuttle
 - Gentoo::
      emerge -av net-proxy/sshuttle
 - NixOS::
      nix-env -iA nixos.sshuttle
 - From PyPI::
      sudo pip install sshuttle
 - Clone::
      git clone https://github.com/sshuttle/sshuttle.git
      cd sshuttle
      sudo ./setup.py install
 - FreeBSD::
      # ports
      cd /usr/ports/net/py-sshuttle && make install clean
      # pkg
      pkg install py39-sshuttle
 - OpenBSD::
      pkg_add sshuttle
 - macOS, via MacPorts::
      sudo port selfupdate
      sudo port install sshuttle
 It is also possible to install into a virtualenv as a non-root user.
 - From PyPI::
      python3 -m venv /tmp/sshuttle
      . /tmp/sshuttle/bin/activate
      pip install sshuttle
 - Clone::
      git clone https://github.com/sshuttle/sshuttle.git
      cd sshuttle
      python3 -m venv /tmp/sshuttle
      . /tmp/sshuttle/bin/activate
      python -m pip install .
 - Homebrew::
      brew install sshuttle
 - Nix::
      nix-shell -p sshuttle
 - Windows::
      pip install sshuttle
--- a/docs/make.bat
+++ b/docs/make.bat
@ -1,242 +0,0 @@
@ECHO OFF
 REM Command file for Sphinx documentation
 if "%SPHINXBUILD%" == "" (
 	set SPHINXBUILD=sphinx-build
 )
 set BUILDDIR=_build
 set ALLSPHINXOPTS=-d %BUILDDIR%/doctrees %SPHINXOPTS% .
 set I18NSPHINXOPTS=%SPHINXOPTS% .
 if NOT "%PAPER%" == "" (
 	set ALLSPHINXOPTS=-D latex_paper_size=%PAPER% %ALLSPHINXOPTS%
 	set I18NSPHINXOPTS=-D latex_paper_size=%PAPER% %I18NSPHINXOPTS%
 )
 if "%1" == "" goto help
 if "%1" == "help" (
 	:help
 	echo.Please use `make ^<target^>` where ^<target^> is one of
 	echo.  html       to make standalone HTML files
 	echo.  dirhtml    to make HTML files named index.html in directories
 	echo.  singlehtml to make a single large HTML file
 	echo.  pickle     to make pickle files
 	echo.  json       to make JSON files
 	echo.  htmlhelp   to make HTML files and a HTML help project
 	echo.  qthelp     to make HTML files and a qthelp project
 	echo.  devhelp    to make HTML files and a Devhelp project
 	echo.  epub       to make an epub
 	echo.  latex      to make LaTeX files, you can set PAPER=a4 or PAPER=letter
 	echo.  text       to make text files
 	echo.  man        to make manual pages
 	echo.  texinfo    to make Texinfo files
 	echo.  gettext    to make PO message catalogs
 	echo.  changes    to make an overview over all changed/added/deprecated items
 	echo.  xml        to make Docutils-native XML files
 	echo.  pseudoxml  to make pseudoxml-XML files for display purposes
 	echo.  linkcheck  to check all external links for integrity
 	echo.  doctest    to run all doctests embedded in the documentation if enabled
 	goto end
 )
 if "%1" == "clean" (
 	for /d %%i in (%BUILDDIR%\*) do rmdir /q /s %%i
 	del /q /s %BUILDDIR%\*
 	goto end
 )
 %SPHINXBUILD% 2> nul
 if errorlevel 9009 (
 	echo.
 	echo.The 'sphinx-build' command was not found. Make sure you have Sphinx
 	echo.installed, then set the SPHINXBUILD environment variable to point
 	echo.to the full path of the 'sphinx-build' executable. Alternatively you
 	echo.may add the Sphinx directory to PATH.
 	echo.
 	echo.If you don't have Sphinx installed, grab it from
 	echo.http://sphinx-doc.org/
 	exit /b 1
 )
 if "%1" == "html" (
 	%SPHINXBUILD% -b html %ALLSPHINXOPTS% %BUILDDIR%/html
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The HTML pages are in %BUILDDIR%/html.
 	goto end
 )
 if "%1" == "dirhtml" (
 	%SPHINXBUILD% -b dirhtml %ALLSPHINXOPTS% %BUILDDIR%/dirhtml
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The HTML pages are in %BUILDDIR%/dirhtml.
 	goto end
 )
 if "%1" == "singlehtml" (
 	%SPHINXBUILD% -b singlehtml %ALLSPHINXOPTS% %BUILDDIR%/singlehtml
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The HTML pages are in %BUILDDIR%/singlehtml.
 	goto end
 )
 if "%1" == "pickle" (
 	%SPHINXBUILD% -b pickle %ALLSPHINXOPTS% %BUILDDIR%/pickle
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished; now you can process the pickle files.
 	goto end
 )
 if "%1" == "json" (
 	%SPHINXBUILD% -b json %ALLSPHINXOPTS% %BUILDDIR%/json
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished; now you can process the JSON files.
 	goto end
 )
 if "%1" == "htmlhelp" (
 	%SPHINXBUILD% -b htmlhelp %ALLSPHINXOPTS% %BUILDDIR%/htmlhelp
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished; now you can run HTML Help Workshop with the ^
 .hhp project file in %BUILDDIR%/htmlhelp.
 	goto end
 )
 if "%1" == "qthelp" (
 	%SPHINXBUILD% -b qthelp %ALLSPHINXOPTS% %BUILDDIR%/qthelp
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished; now you can run "qcollectiongenerator" with the ^
 .qhcp project file in %BUILDDIR%/qthelp, like this:
 	echo.^> qcollectiongenerator %BUILDDIR%\qthelp\sshuttle.qhcp
 	echo.To view the help file:
 	echo.^> assistant -collectionFile %BUILDDIR%\qthelp\sshuttle.ghc
 	goto end
 )
 if "%1" == "devhelp" (
 	%SPHINXBUILD% -b devhelp %ALLSPHINXOPTS% %BUILDDIR%/devhelp
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished.
 	goto end
 )
 if "%1" == "epub" (
 	%SPHINXBUILD% -b epub %ALLSPHINXOPTS% %BUILDDIR%/epub
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The epub file is in %BUILDDIR%/epub.
 	goto end
 )
 if "%1" == "latex" (
 	%SPHINXBUILD% -b latex %ALLSPHINXOPTS% %BUILDDIR%/latex
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished; the LaTeX files are in %BUILDDIR%/latex.
 	goto end
 )
 if "%1" == "latexpdf" (
 	%SPHINXBUILD% -b latex %ALLSPHINXOPTS% %BUILDDIR%/latex
 	cd %BUILDDIR%/latex
 	make all-pdf
 	cd %BUILDDIR%/..
 	echo.
 	echo.Build finished; the PDF files are in %BUILDDIR%/latex.
 	goto end
 )
 if "%1" == "latexpdfja" (
 	%SPHINXBUILD% -b latex %ALLSPHINXOPTS% %BUILDDIR%/latex
 	cd %BUILDDIR%/latex
 	make all-pdf-ja
 	cd %BUILDDIR%/..
 	echo.
 	echo.Build finished; the PDF files are in %BUILDDIR%/latex.
 	goto end
 )
 if "%1" == "text" (
 	%SPHINXBUILD% -b text %ALLSPHINXOPTS% %BUILDDIR%/text
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The text files are in %BUILDDIR%/text.
 	goto end
 )
 if "%1" == "man" (
 	%SPHINXBUILD% -b man %ALLSPHINXOPTS% %BUILDDIR%/man
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The manual pages are in %BUILDDIR%/man.
 	goto end
 )
 if "%1" == "texinfo" (
 	%SPHINXBUILD% -b texinfo %ALLSPHINXOPTS% %BUILDDIR%/texinfo
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The Texinfo files are in %BUILDDIR%/texinfo.
 	goto end
 )
 if "%1" == "gettext" (
 	%SPHINXBUILD% -b gettext %I18NSPHINXOPTS% %BUILDDIR%/locale
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The message catalogs are in %BUILDDIR%/locale.
 	goto end
 )
 if "%1" == "changes" (
 	%SPHINXBUILD% -b changes %ALLSPHINXOPTS% %BUILDDIR%/changes
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.The overview file is in %BUILDDIR%/changes.
 	goto end
 )
 if "%1" == "linkcheck" (
 	%SPHINXBUILD% -b linkcheck %ALLSPHINXOPTS% %BUILDDIR%/linkcheck
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Link check complete; look for any errors in the above output ^
 or in %BUILDDIR%/linkcheck/output.txt.
 	goto end
 )
 if "%1" == "doctest" (
 	%SPHINXBUILD% -b doctest %ALLSPHINXOPTS% %BUILDDIR%/doctest
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Testing of doctests in the sources finished, look at the ^
 results in %BUILDDIR%/doctest/output.txt.
 	goto end
 )
 if "%1" == "xml" (
 	%SPHINXBUILD% -b xml %ALLSPHINXOPTS% %BUILDDIR%/xml
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The XML files are in %BUILDDIR%/xml.
 	goto end
 )
 if "%1" == "pseudoxml" (
 	%SPHINXBUILD% -b pseudoxml %ALLSPHINXOPTS% %BUILDDIR%/pseudoxml
 	if errorlevel 1 exit /b 1
 	echo.
 	echo.Build finished. The pseudo-XML files are in %BUILDDIR%/pseudoxml.
 	goto end
 )
 :end
--- a/docs/manpage.rst
+++ b/docs/manpage.rst
@ -1,503 +0,0 @@
 sshuttle
 ========
 Synopsis
 --------
 **sshuttle** [*options*] **-r** *[username@]sshserver[:port]* \<*subnets* ...\>
 Description
 -----------
 :program:`sshuttle` allows you to create a VPN connection from your
 machine to any remote server that you can connect to via ssh, as long
 as that server has a sufficiently new Python installation.
 To work, you must have root access on the local machine,
 but you can have a normal account on the server.
 It's valid to run :program:`sshuttle` more than once simultaneously on
 a single client machine, connecting to a different server
 every time, so you can be on more than one VPN at once.
 If run on a router, :program:`sshuttle` can forward traffic for your
 entire subnet to the VPN.
 Options
 -------
 .. program:: sshuttle
 .. option:: <subnets>
    A list of subnets to route over the VPN, in the form
    ``a.b.c.d[/width][port[-port]]``. Valid examples are 1.2.3.4 (a
    single IP address) and 1.2.3.4/32 (equivalent to 1.2.3.4),
    1.2.3.0/24 (a 24-bit subnet, ie. with a 255.255.255.0 netmask).
    Specify subnets 0/0 to match all IPv4 addresses and ::/0 to match
    all IPv6 addresses. Any of the previous examples are also valid if
    you append a port or a port range, so 1.2.3.4:8000 will only
    tunnel traffic that has as the destination port 8000 of 1.2.3.4
    and 1.2.3.0/24:8000-9000 will tunnel traffic going to any port
    between 8000 and 9000 (inclusive) for all IPs in the 1.2.3.0/24
    subnet. A hostname can be provided instead of an IP address. If
    the hostname resolves to multiple IPs, all of the IPs are
    included. If a width is provided with a hostname, the width is
    applied to all of the hostnames IPs (if they are all either IPv4
    or IPv6). Widths cannot be supplied to hostnames that resolve to
    both IPv4 and IPv6. Valid examples are example.com,
    example.com:8000, example.com/24, example.com/24:8000 and
    example.com:8000-9000.
 .. option:: --method <auto|nat|nft|tproxy|pf|ipfw>
   Which firewall method should sshuttle use? For auto, sshuttle attempts to
   guess the appropriate method depending on what it can find in PATH. The
   default value is auto.
 .. option:: -l <[ip:]port>, --listen=<[ip:]port>
    Use this ip address and port number as the transparent
    proxy port.  By default :program:`sshuttle` finds an available
    port automatically and listens on IP 127.0.0.1
    (localhost), so you don't need to override it, and
    connections are only proxied from the local machine,
    not from outside machines.  If you want to accept
    connections from other machines on your network (ie. to
    run :program:`sshuttle` on a router) try enabling IP Forwarding in
    your kernel, then using ``--listen 0.0.0.0:0``.
    You can use any name resolving to an IP address of the machine running
    :program:`sshuttle`, e.g. ``--listen localhost``.
    For the nft, tproxy and pf methods this can be an IPv6 address. Use
    this option with comma separated values if required, to provide both
    IPv4 and IPv6 addresses, e.g. ``--listen 127.0.0.1:0,[::1]:0``.
 .. option:: -H, --auto-hosts
    Scan for remote hostnames and update the local /etc/hosts
    file with matching entries for as long as the VPN is
    open.  This is nicer than changing your system's DNS
    (/etc/resolv.conf) settings, for several reasons.  First,
    hostnames are added without domain names attached, so
    you can ``ssh thatserver`` without worrying if your local
    domain matches the remote one.  Second, if you :program:`sshuttle`
    into more than one VPN at a time, it's impossible to
    use more than one DNS server at once anyway, but
    :program:`sshuttle` correctly merges /etc/hosts entries between
    all running copies.  Third, if you're only routing a
    few subnets over the VPN, you probably would prefer to
    keep using your local DNS server for everything else.
    :program:`sshuttle` tries to store a cache of the hostnames in
    ~/.sshuttle.hosts on the remote host. Similarly, it tries to read
    the file when you later reconnect to the host with --auto-hosts
    enabled to quickly populate the host list. When troubleshooting
    this feature, try removing this file on the remote host when
    sshuttle is not running.
 .. option:: -N, --auto-nets
    In addition to the subnets provided on the command
    line, ask the server which subnets it thinks we should
    route, and route those automatically.  The suggestions
    are taken automatically from the server's routing
    table.
    This feature does not detect IPv6 routes. Specify IPv6 subnets
    manually. For example, specify the ``::/0`` subnet on the command
    line to route all IPv6 traffic.
 .. option:: --dns
    Capture local DNS requests and forward to the remote DNS
    server. All queries to any of the local system's DNS
    servers (/etc/resolv.conf and, if it exists,
    /run/systemd/resolve/resolv.conf) will be intercepted and
    resolved on the remote side of the tunnel instead, there
    using the DNS specified via the :option:`--to-ns` option,
    if specified. Only plain DNS traffic sent to these servers
    on port 53 are captured.
 .. option:: --ns-hosts=<server1[,server2[,server3[...]]]>
    Capture local DNS requests to the specified server(s)
    and forward to the remote DNS server. Contrary to the
    :option:`--dns` option, this flag allows to specify the
    DNS server(s) the queries to which to intercept,
    instead of intercepting all DNS traffic on the local
    machine. This can be useful when only certain DNS
    requests should be resolved on the remote side of the
    tunnel, e.g. in combination with dnsmasq.
 .. option:: --to-ns=<server>
    The DNS to forward requests to when remote DNS
    resolution is enabled. If not given, sshuttle will
    simply resolve using the system configured resolver on
    the remote side (via /etc/resolv.conf on the remote
    side).
 .. option:: --python
    Specify the name/path of the remote python interpreter. The
    default is to use ``python3`` (or ``python``, if ``python3``
    fails) in the remote system's PATH.
 .. option:: -r <[username@]sshserver[:port]>, --remote=<[username@]sshserver[:port]>
    The remote hostname and optional username and ssh
    port number to use for connecting to the remote server.
    For example, example.com, testuser@example.com,
    testuser@example.com:2222, or example.com:2244. This
    hostname is passed to ssh, so it will recognize any
    aliases and settings you may have configured in
    ~/.ssh/config.
 .. option:: -x <subnet>, --exclude=<subnet>
    Explicitly exclude this subnet from forwarding.  The
    format of this option is the same as the ``<subnets>``
    option.  To exclude more than one subnet, specify the
    ``-x`` option more than once.  You can say something like
    ``0/0 -x 1.2.3.0/24`` to forward everything except the
    local subnet over the VPN, for example.
 .. option:: -X <file>, --exclude-from=<file>
    Exclude the subnets specified in a file, one subnet per
    line. Useful when you have lots of subnets to exclude.
 .. option:: -v, --verbose
    Print more information about the session.  This option
    can be used more than once for increased verbosity.  By
    default, :program:`sshuttle` prints only error messages.
 .. option:: -e, --ssh-cmd
    The command to use to connect to the remote server. The
    default is just ``ssh``.  Use this if your ssh client is
    in a non-standard location or you want to provide extra
    options to the ssh command, for example, ``-e 'ssh -v'``.
 .. option:: --remote-shell
    For Windows targets, specify configured remote shell program alternative to defacto posix shell.
    It would be either ``cmd`` or ``powershell`` unless something like git-bash is in use.
 .. option:: --no-cmd-delimiter
    Do not add a double dash (--) delimiter before invoking Python on
    the remote host. This option is useful when the ssh command used
    to connect is a custom command that does not interpret this
    delimiter correctly.
 .. option:: --seed-hosts
    A comma-separated list of hostnames to use to
    initialize the :option:`--auto-hosts` scan algorithm.
    :option:`--auto-hosts` does things like poll netstat output
    for lists of local hostnames, but can speed things up
    if you use this option to give it a few names to start
    from.
    If this option is used *without* :option:`--auto-hosts`,
    then the listed hostnames will be scanned and added, but
    no further hostnames will be added.
 .. option:: --no-latency-control
    Sacrifice latency to improve bandwidth benchmarks. ssh
    uses really big socket buffers, which can overload the
    connection if you start doing large file transfers,
    thus making all your other sessions inside the same
    tunnel go slowly. Normally, :program:`sshuttle` tries to avoid
    this problem using a "fullness check" that allows only
    a certain amount of outstanding data to be buffered at
    a time.  But on high-bandwidth links, this can leave a
    lot of your bandwidth underutilized.  It also makes
    :program:`sshuttle` seem slow in bandwidth benchmarks (benchmarks
    rarely test ping latency, which is what :program:`sshuttle` is
    trying to control).  This option disables the latency
    control feature, maximizing bandwidth usage.  Use at
    your own risk.
 .. option:: --latency-buffer-size
    Set the size of the buffer used in latency control. The
    default is ``32768``. Changing this option allows a compromise
    to be made between latency and bandwidth without completely
    disabling latency control (with :option:`--no-latency-control`).
 .. option:: -D, --daemon
    Automatically fork into the background after connecting
    to the remote server.  Implies :option:`--syslog`.
 .. option:: -s <file>, --subnets=<file>
    Include the subnets specified in a file instead of on the
    command line. One subnet per line.
 .. option:: --syslog
    after connecting, send all log messages to the
    :manpage:`syslog(3)` service instead of stderr.  This is
    implicit if you use :option:`--daemon`.
 .. option:: --pidfile=<pidfilename>
    when using :option:`--daemon`, save :program:`sshuttle`'s pid to
    *pidfilename*.  The default is ``sshuttle.pid`` in the
    current directory.
 .. option:: --disable-ipv6
    Disable IPv6 support for methods that support it (nat, nft,
    tproxy, and pf).
 .. option:: --firewall
    (internal use only) run the firewall manager.  This is
    the only part of :program:`sshuttle` that must run as root.  If
    you start :program:`sshuttle` as a non-root user, it will
    automatically run ``sudo`` or ``su`` to start the firewall
    manager, but the core of :program:`sshuttle` still runs as a
    normal user.
 .. option:: --hostwatch
    (internal use only) run the hostwatch daemon.  This
    process runs on the server side and collects hostnames for
    the :option:`--auto-hosts` option.  Using this option by itself
    makes it a lot easier to debug and test the :option:`--auto-hosts`
    feature.
 .. option:: --sudoers-no-modify
    sshuttle prints a configuration to stdout which allows a user to
    run sshuttle without a password. This option is INSECURE because,
    with some cleverness, it also allows the user to run any command
    as root without a password. The output also includes a suggested
    method for you to install the configuration.
    Use --sudoers-user to modify the user that it applies to.
 .. option:: --sudoers-user
    Set the user name or group with %group_name for passwordless
    operation. Default is the current user. Set to ALL for all users
    (NOT RECOMMENDED: See note about security in --sudoers-no-modify
    documentation above). Only works with the --sudoers-no-modify
    option.
 .. option:: -t <mark>, --tmark=<mark>
    An option used by the tproxy method: Use the specified traffic
    mark. The mark must be a hexadecimal value. Defaults to 0x01.
 .. option:: --version
    Print program version.
 Configuration File
 ------------------
 All the options described above can optionally be specified in a configuration
 file.
 To run :program:`sshuttle` with options defined in, e.g., `/etc/sshuttle.conf`
 just pass the path to the file preceded by the `@` character, e.g.
 `@/etc/sshuttle.conf`.
 When running :program:`sshuttle` with options defined in a configuration file,
 options can still be passed via the command line in addition to what is
 defined in the file. If a given option is defined both in the file and in
 the command line, the value in the command line will take precedence.
 Arguments read from a file must be one per line, as shown below::
    value
    --option1
    value1
    --option2
    value2
 The configuration file supports comments for human-readable
 annotations. For example::
    # company-internal API
    8.8.8.8/32
    # home IoT
    192.168.63.0/24
 Environment Variable
 --------------------
 You can specify command line options with the `SSHUTTLE_ARGS` environment
 variable. If a given option is defined in both the environment variable and
 command line, the value on the command line will take precedence.
 For example::
    SSHUTTLE_ARGS="-e 'ssh -v' --dns" sshuttle -r example.com 0/0
 Examples
 --------
 Use the following command to route all IPv4 TCP traffic through remote
 (-r) host example.com (and possibly other traffic too, depending on
 the selected --method). The 0/0 subnet, short for 0.0.0.0/0, matches
 all IPv4 addresses. The ::/0 subnet, matching all IPv6 addresses could
 be added to the example. We also exclude (-x) example.com:22 so that
 we can establish ssh connections from our local machine to the remote
 host without them being routed through sshuttle. Excluding the remote
 host may be necessary on some machines for sshuttle to work properly.
 Press Ctrl+C to exit. To also route DNS queries through sshuttle, try
 adding --dns. Add or remove -v options to see more or less
 information::
    $ sshuttle -r example.com -x example.com:22 0/0
    Starting sshuttle proxy (version ...).
    [local sudo] Password:
    fw: Starting firewall with Python version 3.9.5
    fw: ready method name nat.
    c : IPv6 disabled since it isn't supported by method nat.
    c : Method: nat
    c : IPv4: on
    c : IPv6: off (not available with nat method)
    c : UDP : off (not available with nat method)
    c : DNS : off (available)
    c : User: off (available)
    c : Subnets to forward through remote host (type, IP, cidr mask width, startPort, endPort):
    c :   (<AddressFamily.AF_INET: 2>, '0.0.0.0', 0, 0, 0)
    c : Subnets to exclude from forwarding:
    c :   (<AddressFamily.AF_INET: 2>, '...', 32, 22, 22)
    c :   (<AddressFamily.AF_INET: 2>, '127.0.0.1', 32, 0, 0)
    c : TCP redirector listening on ('127.0.0.1', 12299).
    c : Starting client with Python version 3.9.5
    c : Connecting to server...
    user@example.com's password:
     s: Starting server with Python version 3.6.8
     s: latency control setting = True
     s: auto-nets:False
    c : Connected to server.
    fw: setting up.
    fw: iptables -w -t nat -N sshuttle-12299
    fw: iptables -w -t nat -F sshuttle-12299
    ...
    Accept: 192.168.42.121:60554 -> 77.141.99.22:22.
    ^C
    c : Keyboard interrupt: exiting.
    c : SW'unknown':Mux#1: deleting (1 remain)
    c : SW#7:192.168.42.121:60554: deleting (0 remain)
 Connect to a remote server, with automatic hostname
 and subnet guessing::
    $ sshuttle -vNHr example.com -x example.com:22
    Starting sshuttle proxy (version ...).
    [local sudo] Password:
    fw: Starting firewall with Python version 3.9.5
    fw: ready method name nat.
    c : IPv6 disabled since it isn't supported by method nat.
    c : Method: nat
    c : IPv4: on
    c : IPv6: off (not available with nat method)
    c : UDP : off (not available with nat method)
    c : DNS : off (available)
    c : User: off (available)
    c : Subnets to forward through remote host (type, IP, cidr mask width, startPort, endPort):
    c : NOTE: Additional subnets to forward may be added below by --auto-nets.
    c : Subnets to exclude from forwarding:
    c :   (<AddressFamily.AF_INET: 2>, '...', 32, 22, 22)
    c :   (<AddressFamily.AF_INET: 2>, '127.0.0.1', 32, 0, 0)
    c : TCP redirector listening on ('127.0.0.1', 12300).
    c : Starting client with Python version 3.9.5
    c : Connecting to server...
    user@example.com's password:
     s: Starting server with Python version 3.6.8
     s: latency control setting = True
     s: auto-nets:True
    c : Connected to server.
    c : seed_hosts: []
     s: available routes:
     s:   77.141.99.0/24
    fw: setting up.
    fw: iptables -w -t nat -N sshuttle-12300
    fw: iptables -w -t nat -F sshuttle-12300
    ...
    c : Accept: 192.168.42.121:60554 -> 77.141.99.22:22.
    ^C
    c : Keyboard interrupt: exiting.
    c : SW'unknown':Mux#1: deleting (1 remain)
    c : SW#7:192.168.42.121:60554: deleting (0 remain)
 Run :program:`sshuttle` with a `/etc/sshuttle.conf` configuration file::
    $ sshuttle @/etc/sshuttle.conf
 Use the options defined in `/etc/sshuttle.conf` but be more verbose::
    $ sshuttle @/etc/sshuttle.conf -vvv
 Override the remote server defined in `/etc/sshuttle.conf`::
    $ sshuttle @/etc/sshuttle.conf -r otheruser@test.example.com
 Example configuration file::
    192.168.0.0/16
    --remote
    user@example.com
 Discussion
 ----------
 When it starts, :program:`sshuttle` creates an ssh session to the
 server specified by the ``-r`` option.
 After connecting to the remote server, :program:`sshuttle` uploads its
 (python) source code to the remote end and executes it
 there.  Thus, you don't need to install :program:`sshuttle` on the
 remote server, and there are never :program:`sshuttle` version
 conflicts between client and server.
 Unlike most VPNs, :program:`sshuttle` forwards sessions, not packets.
 That is, it uses kernel transparent proxying (`iptables
 REDIRECT` rules on Linux) to
 capture outgoing TCP sessions, then creates entirely
 separate TCP sessions out to the original destination at
 the other end of the tunnel.
 Packet-level forwarding (eg. using the tun/tap devices on
 Linux) seems elegant at first, but it results in
 several problems, notably the 'tcp over tcp' problem.  The
 tcp protocol depends fundamentally on packets being dropped
 in order to implement its congestion control algorithm; if
 you pass tcp packets through a tcp-based tunnel (such as
 ssh), the inner tcp packets will never be dropped, and so
 the inner tcp stream's congestion control will be
 completely broken, and performance will be terrible.  Thus,
 packet-based VPNs (such as IPsec and openvpn) cannot use
 tcp-based encrypted streams like ssh or ssl, and have to
 implement their own encryption from scratch, which is very
 complex and error prone.
 :program:`sshuttle`'s simplicity comes from the fact that it can
 safely use the existing ssh encrypted tunnel without
 incurring a performance penalty.  It does this by letting
 the client-side kernel manage the incoming tcp stream, and
 the server-side kernel manage the outgoing tcp stream;
 there is no need for congestion control to be shared
 between the two separate streams, so a tcp-based tunnel is
 fine.
 .. seealso::
   :manpage:`ssh(1)`, :manpage:`python(1)`
--- a/docs/openwrt.rst
+++ b/docs/openwrt.rst
@ -1,8 +0,0 @@
 OpenWRT
 ========
 Run::
    opkg install python3 python3-pip iptables-mod-extra iptables-mod-nat-extra iptables-mod-ipopt
    python3 /usr/bin/pip3 install sshuttle
    sshuttle -l 0.0.0.0 -r <IP> -x 192.168.1.1 0/0
--- a/docs/overview.rst
+++ b/docs/overview.rst
@ -1,26 +0,0 @@
 Overview
 ========
 As far as I know, sshuttle is the only program that solves the following
 common case:
 - Your client machine (or router) is Linux, MacOS, FreeBSD, OpenBSD or pfSense.
 - You have access to a remote network via ssh.
 - You don't necessarily have admin access on the remote network.
 - The remote network has no VPN, or only stupid/complex VPN
  protocols (IPsec, PPTP, etc). Or maybe you *are* the
  admin and you just got frustrated with the awful state of
  VPN tools.
 - You don't want to create an ssh port forward for every
  single host/port on the remote network.
 - You hate openssh's port forwarding because it's randomly
  slow and/or stupid.
 - You can't use openssh's PermitTunnel feature because
  it's disabled by default on openssh servers; plus it does
  TCP-over-TCP, which has terrible performance (see below).
--- a/docs/platform.rst
+++ b/docs/platform.rst
@ -1,12 +0,0 @@
 Platform Specific Notes
 =======================
 Contents:
 .. toctree::
   :maxdepth: 2
   chromeos
   tproxy
   windows
   openwrt
--- a/docs/requirements.rst
+++ b/docs/requirements.rst
@ -1,97 +0,0 @@
 Requirements
 ============
 Client side Requirements
 ------------------------
 - sudo, or root access on your client machine.
  (The server doesn't need admin access.)
 - Python 3.9 or greater.
 Linux with NAT method
 ~~~~~~~~~~~~~~~~~~~~~
 Supports:
 * IPv4 TCP
 * IPv4 DNS
 * IPv6 TCP
 * IPv6 DNS
 Requires:
 * iptables DNAT and REDIRECT modules. ip6tables for IPv6.
 Linux with nft method
 ~~~~~~~~~~~~~~~~~~~~~
 Supports
 * IPv4 TCP
 * IPv4 DNS
 * IPv6 TCP
 * IPv6 DNS
 Requires:
 * nftables
 Linux with TPROXY method
 ~~~~~~~~~~~~~~~~~~~~~~~~
 Supports:
 * IPv4 TCP
 * IPv4 UDP
 * IPv4 DNS
 * IPv6 TCP
 * IPv6 UDP
 * IPv6 DNS
 MacOS / FreeBSD / OpenBSD / pfSense
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Method: pf
 Supports:
 * IPv4 TCP
 * IPv4 DNS
 * IPv6 TCP
 * IPv6 DNS
 Requires:
 * You need to have the pfctl command.
 Windows
 ~~~~~~~
 Experimental built-in support available. See :doc:`windows` for more information.
 Server side Requirements
 ------------------------
 - Python 3.9 or greater.
 Additional Suggested Software
 -----------------------------
 - If you are using systemd, sshuttle can notify it when the connection to
  the remote end is established and the firewall rules are installed. For
  this feature to work you must configure the process start-up type for the
  sshuttle service unit to notify, as shown in the example below.
 .. code-block:: ini
   :emphasize-lines: 6
   [Unit]
   Description=sshuttle
   After=network.target
   [Service]
   Type=notify
   ExecStart=/usr/bin/sshuttle --dns --remote <user>@<server> <subnets...>
   [Install]
   WantedBy=multi-user.target
--- a/docs/support.rst
+++ b/docs/support.rst
@ -1,11 +0,0 @@
 Support
 =======
 Mailing list:
 * Subscribe by sending a message to <sshuttle+subscribe@googlegroups.com>
 * List archives are at: http://groups.google.com/group/sshuttle
 Issue tracker and pull requests at github:
 * https://github.com/sshuttle/sshuttle
--- a/docs/tproxy.rst
+++ b/docs/tproxy.rst
@ -1,40 +0,0 @@
 TPROXY
 ======
 TPROXY is the only method that supports UDP.
 There are some things you need to consider for TPROXY to work:
 - The following commands need to be run first as root. This only needs to be
  done once after booting up::
      ip route add local default dev lo table 100
      ip rule add fwmark {TMARK} lookup 100
      ip -6 route add local default dev lo table 100
      ip -6 rule add fwmark {TMARK} lookup 100
  where {TMARK} is the identifier mark passed with -t or --tmark flag
  as a hexadecimal string (default value is '0x01').
 - The ``--auto-nets`` feature does not detect IPv6 routes automatically. Add IPv6
  routes manually. e.g. by adding ``'::/0'`` to the end of the command line.
 - The client needs to be run as root. e.g.::
      sudo SSH_AUTH_SOCK="$SSH_AUTH_SOCK" $HOME/tree/sshuttle.tproxy/sshuttle --method=tproxy ...
 - You may need to exclude the IP address of the server you are connecting to.
  Otherwise sshuttle may attempt to intercept the ssh packets, which will not
  work. Use the ``--exclude`` parameter for this.
 - You need the ``--method=tproxy`` parameter, as above.
 - The routes for the outgoing packets must already exist. For example, if your
  connection does not have IPv6 support, no IPv6 routes will exist, IPv6
  packets will not be generated and sshuttle cannot intercept them::
      telnet -6 www.google.com 80
      Trying 2404:6800:4001:805::1010...
      telnet: Unable to connect to remote host: Network is unreachable
  Add some dummy routes to external interfaces. Make sure they get removed
  however after sshuttle exits.
--- a/docs/trivia.rst
+++ b/docs/trivia.rst
@ -1,35 +0,0 @@
 Useless Trivia
 ==============
 This section written by the original author, Avery Pennarun
 <apenwarr@gmail.com>.
 Back in 1998, I released the first version of `Tunnel
 Vision <http://alumnit.ca/wiki/?TunnelVisionReadMe>`_, a semi-intelligent VPN
 client for Linux.  Unfortunately, I made two big mistakes: I implemented the
 key exchange myself (oops), and I ended up doing TCP-over-TCP (double oops).
 The resulting program worked okay - and people used it for years - but the
 performance was always a bit funny.  And nobody ever found any security flaws
 in my key exchange, either, but that doesn't mean anything. :)
 The same year, dcoombs and I also released Fast Forward, a proxy server
 supporting transparent proxying.  Among other things, we used it for
 automatically splitting traffic across more than one Internet connection (a
 tool we called "Double Vision").
 I was still in university at the time.  A couple years after that, one of my
 professors was working with some graduate students on the technology that would
 eventually become `Slipstream Internet Acceleration
 <http://www.slipstream.com/>`_.  He asked me to do a contract for him to build
 an initial prototype of a transparent proxy server for mobile networks.  The
 idea was similar to sshuttle: if you reassemble and then disassemble the TCP
 packets, you can reduce latency and improve performance vs.  just forwarding
 the packets over a plain VPN or mobile network.  (It's unlikely that any of my
 code has persisted in the Slipstream product today, but the concept is still
 pretty cool.  I'm still horrified that people use plain TCP on complex mobile
 networks with crazily variable latency, for which it was never really
 intended.)
 That project I did for Slipstream was what first gave me the idea to merge
 the concepts of Fast Forward, Double Vision, and Tunnel Vision into a single
 program that was the best of all worlds.  And here we are, at last.
 You're welcome.
--- a/docs/usage.rst
+++ b/docs/usage.rst
@ -1,93 +0,0 @@
 Usage
 =====
 .. note::
    For information on usage with Windows, see the :doc:`windows` section.
    For information on using the TProxy method, see the :doc:`tproxy` section.
 Forward all traffic::
    sshuttle -r username@sshserver 0.0.0.0/0
 - Use the :option:`sshuttle -r` parameter to specify a remote server.
  On some systems, you may also need to use the :option:`sshuttle -x`
  parameter to exclude sshserver or sshserver:22 so that your local
  machine can communicate directly to sshserver without it being
  redirected by sshuttle.
 - By default sshuttle will automatically choose a method to use. Override with
  the :option:`sshuttle --method` parameter.
 - There is a shortcut for 0.0.0.0/0 for those that value
  their wrists::
      sshuttle -r username@sshserver 0/0
 - For 'My VPN broke and need a temporary solution FAST to access local IPv4 addresses'::
      sshuttle --dns -NHr username@sshserver 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16
 If you would also like your DNS queries to be proxied
 through the DNS server of the server you are connect to::
  sshuttle --dns -r username@sshserver 0/0
 The above is probably what you want to use to prevent
 local network attacks such as Firesheep and friends.
 See the documentation for the :option:`sshuttle --dns` parameter.
 (You may be prompted for one or more passwords; first, the local password to
 become root using sudo, and then the remote ssh password.  Or you might have
 sudo and ssh set up to not require passwords, in which case you won't be
 prompted at all.)
 Usage Notes
 -----------
 That's it!  Now your local machine can access the remote network as if you
 were right there.  And if your "client" machine is a router, everyone on
 your local network can make connections to your remote network.
 You don't need to install sshuttle on the remote server;
 the remote server just needs to have python available.
 sshuttle will automatically upload and run its source code
 to the remote python interpreter.
 This creates a transparent proxy server on your local machine for all IP
 addresses that match 0.0.0.0/0.  (You can use more specific IP addresses if
 you want; use any number of IP addresses or subnets to change which
 addresses get proxied.  Using 0.0.0.0/0 proxies *everything*, which is
 interesting if you don't trust the people on your local network.)
 Any TCP session you initiate to one of the proxied IP addresses will be
 captured by sshuttle and sent over an ssh session to the remote copy of
 sshuttle, which will then regenerate the connection on that end, and funnel
 the data back and forth through ssh.
 Fun, right?  A poor man's instant VPN, and you don't even have to have
 admin access on the server.
 Sudoers File
 ------------
 sshuttle can generate a sudoers.d file for Linux and MacOS. This
 allows one or more users to run sshuttle without entering the
 local sudo password. **WARNING:** This option is *insecure*
 because, with some cleverness, it also allows these users to run any
 command (via the --ssh-cmd option) as root without a password.
 To print a sudo configuration file and see a suggested way to install it, run::
  sshuttle --sudoers-no-modify
 A custom user or group can be set with the 
 :option:`sshuttle --sudoers-no-modify --sudoers-user {user_descriptor}`
 option. Valid values for this vary based on how your system is configured.
 Values such as usernames, groups prepended with `%` and sudoers user 
 aliases will work. See the sudoers manual for more information on valid
 user-specified actions. The option must be used with `--sudoers-no-modify`::
  sshuttle --sudoers-no-modify --sudoers-user mike
  sshuttle --sudoers-no-modify --sudoers-user %sudo
--- a/docs/windows.rst
+++ b/docs/windows.rst
@ -1,28 +0,0 @@
 Microsoft Windows
 =================
 Experimental native support::
 Experimental built-in support for Windows is available through `windivert` method.
 You have to install https://pypi.org/project/pydivert package.  You need Administrator privileges to use windivert method
 Notes
 -  sshuttle should be executed from admin shell (Automatic firewall process admin elevation is not available)
 -  TCP/IPv4 supported (IPv6/UDP/DNS are not available)
 Use Linux VM on Windows::
 What we can really do is to create a Linux VM with Vagrant (or simply
 Virtualbox if you like). In the Vagrant settings, remember to turn on bridged
 NIC. Then, run sshuttle inside the VM like below::
    sshuttle -l 0.0.0.0 -x 10.0.0.0/8 -x 192.168.0.0/16 0/0
 10.0.0.0/8 excludes NAT traffic of Vagrant and 192.168.0.0/16 excludes
 traffic to local area network (assuming that we're using 192.168.0.0 subnet).
 Assuming the VM has the IP 192.168.1.200 obtained on the bridge NIC (we can
 configure that in Vagrant), we can then ask Windows to route all its traffic
 via the VM by running the following in cmd.exe with admin right::
    route add 0.0.0.0 mask 0.0.0.0 192.168.1.200
--- a/firewall.py
+++ b/firewall.py
@ -0,0 +1,536 @@
 import re, errno, socket, select, signal, struct
 import compat.ssubprocess as ssubprocess
 import helpers, ssyslog
 from helpers import *
 # python doesn't have a definition for this
 IPPROTO_DIVERT = 254
 # return values from sysctl_set
 SUCCESS = 0
 SAME = 1
 FAILED = -1
 NONEXIST = -2
 def nonfatal(func, *args):
    try:
        func(*args)
    except Fatal, e:
        log('error: %s\n' % e)
 def _call(argv):
    debug1('>> %s\n' % ' '.join(argv))
    rv = ssubprocess.call(argv)
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
    return rv
 def ipt_chain_exists(name):
    argv = ['iptables', '-t', 'nat', '-nL']
    p = ssubprocess.Popen(argv, stdout = ssubprocess.PIPE)
    for line in p.stdout:
        if line.startswith('Chain %s ' % name):
            return True
    rv = p.wait()
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
 def ipt(*args):
    argv = ['iptables', '-t', 'nat'] + list(args)
    _call(argv)
 _no_ttl_module = False
 def ipt_ttl(*args):
    global _no_ttl_module
    if not _no_ttl_module:
        # we avoid infinite loops by generating server-side connections
        # with ttl 42.  This makes the client side not recapture those
        # connections, in case client == server.
        try:
            argsplus = list(args) + ['-m', 'ttl', '!', '--ttl', '42']
            ipt(*argsplus)
        except Fatal:
            ipt(*args)
            # we only get here if the non-ttl attempt succeeds
            log('sshuttle: warning: your iptables is missing '
                'the ttl module.\n')
            _no_ttl_module = True
    else:
        ipt(*args)
 # We name the chain based on the transproxy port number so that it's possible
 # to run multiple copies of sshuttle at the same time.  Of course, the
 # multiple copies shouldn't have overlapping subnets, or only the most-
 # recently-started one will win (because we use "-I OUTPUT 1" instead of
 # "-A OUTPUT").
 def do_iptables(port, dnsport, subnets):
    chain = 'sshuttle-%s' % port
    # basic cleanup/setup of chains
    if ipt_chain_exists(chain):
        nonfatal(ipt, '-D', 'OUTPUT', '-j', chain)
        nonfatal(ipt, '-D', 'PREROUTING', '-j', chain)
        nonfatal(ipt, '-F', chain)
        ipt('-X', chain)
    if subnets or dnsport:
        ipt('-N', chain)
        ipt('-F', chain)
        ipt('-I', 'OUTPUT', '1', '-j', chain)
        ipt('-I', 'PREROUTING', '1', '-j', chain)
    if subnets:
        # create new subnet entries.  Note that we're sorting in a very
        # particular order: we need to go from most-specific (largest swidth)
        # to least-specific, and at any given level of specificity, we want
        # excludes to come first.  That's why the columns are in such a non-
        # intuitive order.
        for swidth,sexclude,snet in sorted(subnets, reverse=True):
            if sexclude:
                ipt('-A', chain, '-j', 'RETURN',
                    '--dest', '%s/%s' % (snet,swidth),
                    '-p', 'tcp')
            else:
                ipt_ttl('-A', chain, '-j', 'REDIRECT',
                        '--dest', '%s/%s' % (snet,swidth),
                        '-p', 'tcp',
                        '--to-ports', str(port))
    if dnsport:
        nslist = resolvconf_nameservers()
        for ip in nslist:
            ipt_ttl('-A', chain, '-j', 'REDIRECT',
                    '--dest', '%s/32' % ip,
                    '-p', 'udp',
                    '--dport', '53',
                    '--to-ports', str(dnsport))
 def ipfw_rule_exists(n):
    argv = ['ipfw', 'list']
    p = ssubprocess.Popen(argv, stdout = ssubprocess.PIPE)
    found = False
    for line in p.stdout:
        if line.startswith('%05d ' % n):
            if not ('ipttl 42' in line
                    or ('skipto %d' % (n+1)) in line
                    or 'check-state' in line):
                log('non-sshuttle ipfw rule: %r\n' % line.strip())
                raise Fatal('non-sshuttle ipfw rule #%d already exists!' % n)
            found = True
    rv = p.wait()
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
    return found
 _oldctls = {}
 def _fill_oldctls(prefix):
    argv = ['sysctl', prefix]
    p = ssubprocess.Popen(argv, stdout = ssubprocess.PIPE)
    for line in p.stdout:
        assert(line[-1] == '\n')
        (k,v) = line[:-1].split(': ', 1)
        _oldctls[k] = v
    rv = p.wait()
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
    if not line:
        raise Fatal('%r returned no data' % (argv,))
 KERNEL_FLAGS_PATH = '/Library/Preferences/SystemConfiguration/com.apple.Boot'
 KERNEL_FLAGS_NAME = 'Kernel Flags'
 def _defaults_read_kernel_flags():
    argv = ['defaults', 'read', KERNEL_FLAGS_PATH, KERNEL_FLAGS_NAME]
    debug1('>> %s\n' % ' '.join(argv))
    p = ssubprocess.Popen(argv, stdout = ssubprocess.PIPE)
    flagstr = p.stdout.read().strip()
    rv = p.wait()
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
    flags = flagstr and flagstr.split(' ') or []
    return flags
 def _defaults_write_kernel_flags(flags):
    flagstr = ' '.join(flags)
    argv = ['defaults', 'write', KERNEL_FLAGS_PATH, KERNEL_FLAGS_NAME,
            flagstr]
    _call(argv)
    argv = ['plutil', '-convert', 'xml1', KERNEL_FLAGS_PATH + '.plist']
    _call(argv)
 def defaults_write_kernel_flag(name, val):
    flags = _defaults_read_kernel_flags()
    found = 0
    for i in range(len(flags)):
        if flags[i].startswith('%s=' % name):
            found += 1
            flags[i] = '%s=%s' % (name, val)
    if not found:
        flags.insert(0, '%s=%s' % (name, val))
    _defaults_write_kernel_flags(flags)
 def _sysctl_set(name, val):
    argv = ['sysctl', '-w', '%s=%s' % (name, val)]
    debug1('>> %s\n' % ' '.join(argv))
    return ssubprocess.call(argv, stdout = open('/dev/null', 'w'))
 _changedctls = []
 def sysctl_set(name, val, permanent=False):
    PREFIX = 'net.inet.ip'
    assert(name.startswith(PREFIX + '.'))
    val = str(val)
    if not _oldctls:
        _fill_oldctls(PREFIX)
    if not (name in _oldctls):
        debug1('>> No such sysctl: %r\n' % name)
        return NONEXIST
    oldval = _oldctls[name]
    if val == oldval:
        return SAME
    rv = _sysctl_set(name, val)
    if rv != 0:
        return FAILED
    if permanent:
        debug1('>>   ...saving permanently in /etc/sysctl.conf\n')
        f = open('/etc/sysctl.conf', 'a')
        f.write('\n'
                '# Added by sshuttle\n'
                '%s=%s\n' % (name, val))
        f.close()
    else:
        _changedctls.append(name)
    return SUCCESS
 def _udp_unpack(p):
    src = (socket.inet_ntoa(p[12:16]), struct.unpack('!H', p[20:22])[0])
    dst = (socket.inet_ntoa(p[16:20]), struct.unpack('!H', p[22:24])[0])
    return src, dst
 def _udp_repack(p, src, dst):
    addrs = socket.inet_aton(src[0]) + socket.inet_aton(dst[0])
    ports = struct.pack('!HH', src[1], dst[1])
    return p[:12] + addrs + ports + p[24:]
 _real_dns_server = [None]
 def _handle_diversion(divertsock, dnsport):
    p,tag = divertsock.recvfrom(4096)
    src,dst = _udp_unpack(p)
    debug3('got diverted packet from %r to %r\n' % (src, dst))
    if dst[1] == 53:
        # outgoing DNS
        debug3('...packet is a DNS request.\n')
        _real_dns_server[0] = dst
        dst = ('127.0.0.1', dnsport)
    elif src[1] == dnsport:
        if islocal(src[0]):
            debug3('...packet is a DNS response.\n')
            src = _real_dns_server[0]
    else:
        log('weird?! unexpected divert from %r to %r\n' % (src, dst))
        assert(0)
    newp = _udp_repack(p, src, dst)
    divertsock.sendto(newp, tag)
 def ipfw(*args):
    argv = ['ipfw', '-q'] + list(args)
    _call(argv)
 def do_ipfw(port, dnsport, subnets):
    sport = str(port)
    xsport = str(port+1)
    # cleanup any existing rules
    if ipfw_rule_exists(port):
        ipfw('delete', sport)
    while _changedctls:
        name = _changedctls.pop()
        oldval = _oldctls[name]
        _sysctl_set(name, oldval)
    if subnets or dnsport:
        sysctl_set('net.inet.ip.fw.enable', 1)
        # This seems to be needed on MacOS 10.6 and 10.7.  For more
        # information, see:
        #   http://groups.google.com/group/sshuttle/browse_thread/thread/bc32562e17987b25/6d3aa2bb30a1edab
        # and
        #   http://serverfault.com/questions/138622/transparent-proxying-leaves-sockets-with-syn-rcvd-in-macos-x-10-6-snow-leopard
        changeflag = sysctl_set('net.inet.ip.scopedroute', 0, permanent=True)
        if changeflag == SUCCESS:
            log("\n"
                "        WARNING: ONE-TIME NETWORK DISRUPTION:\n"
                "        =====================================\n"
                "sshuttle has changed a MacOS kernel setting to work around\n"
                "a bug in MacOS 10.6.  This will cause your network to drop\n"
                "within 5-10 minutes unless you restart your network\n"
                "interface (change wireless networks or unplug/plug the\n"
                "ethernet port) NOW, then restart sshuttle.  The fix is\n"
                "permanent; you only have to do this once.\n\n")
            sys.exit(1)
        elif changeflag == FAILED:
            # On MacOS 10.7, the scopedroute sysctl became read-only, so
            # we have to fix it using a kernel boot parameter instead,
            # which requires rebooting.  For more, see:
            #   http://groups.google.com/group/sshuttle/browse_thread/thread/a42505ca33e1de80/e5e8f3e5a92d25f7
            log('Updating kernel boot flags.\n')
            defaults_write_kernel_flag('net.inet.ip.scopedroute', 0)
            log("\n"
                "        YOU MUST REBOOT TO USE SSHUTTLE\n"
                "        ===============================\n"
                "sshuttle has changed a MacOS kernel boot-time setting\n"
                "to work around a bug in MacOS 10.7 Lion.  You will need\n"
                "to reboot before it takes effect.  You only have to\n"
                "do this once.\n\n")
            sys.exit(EXITCODE_NEEDS_REBOOT)
        ipfw('add', sport, 'check-state', 'ip',
             'from', 'any', 'to', 'any')
    if subnets:
        # create new subnet entries
        for swidth,sexclude,snet in sorted(subnets, reverse=True):
            if sexclude:
                ipfw('add', sport, 'skipto', xsport,
                     'tcp',
                     'from', 'any', 'to', '%s/%s' % (snet,swidth))
            else:
                ipfw('add', sport, 'fwd', '127.0.0.1,%d' % port,
                     'tcp',
                     'from', 'any', 'to', '%s/%s' % (snet,swidth),
                     'not', 'ipttl', '42', 'keep-state', 'setup')
    # This part is much crazier than it is on Linux, because MacOS (at least
    # 10.6, and probably other versions, and maybe FreeBSD too) doesn't
    # correctly fixup the dstip/dstport for UDP packets when it puts them
    # through a 'fwd' rule.  It also doesn't fixup the srcip/srcport in the
    # response packet.  In Linux iptables, all that happens magically for us,
    # so we just redirect the packets and relax.
    #
    # On MacOS, we have to fix the ports ourselves.  For that, we use a
    # 'divert' socket, which receives raw packets and lets us mangle them.
    #
    # Here's how it works.  Let's say the local DNS server is 1.1.1.1:53,
    # and the remote DNS server is 2.2.2.2:53, and the local transproxy port
    # is 10.0.0.1:12300, and a client machine is making a request from
    # 10.0.0.5:9999. We see a packet like this:
    #    10.0.0.5:9999 -> 1.1.1.1:53
    # Since the destip:port matches one of our local nameservers, it will
    # match a 'fwd' rule, thus grabbing it on the local machine.  However,
    # the local kernel will then see a packet addressed to *:53 and
    # not know what to do with it; there's nobody listening on port 53.  Thus,
    # we divert it, rewriting it into this:
    #    10.0.0.5:9999 -> 10.0.0.1:12300
    # This gets proxied out to the server, which sends it to 2.2.2.2:53,
    # and the answer comes back, and the proxy sends it back out like this:
    #    10.0.0.1:12300 -> 10.0.0.5:9999
    # But that's wrong!  The original machine expected an answer from
    # 1.1.1.1:53, so we have to divert the *answer* and rewrite it:
    #    1.1.1.1:53 -> 10.0.0.5:9999
    #
    # See?  Easy stuff.
    if dnsport:
        divertsock = socket.socket(socket.AF_INET, socket.SOCK_RAW,
                                   IPPROTO_DIVERT)
        divertsock.bind(('0.0.0.0', port)) # IP field is ignored
        nslist = resolvconf_nameservers()
        for ip in nslist:
            # relabel and then catch outgoing DNS requests
            ipfw('add', sport, 'divert', sport,
                 'udp',
                 'from', 'any', 'to', '%s/32' % ip, '53',
                 'not', 'ipttl', '42')
        # relabel DNS responses
        ipfw('add', sport, 'divert', sport,
             'udp',
             'from', 'any', str(dnsport), 'to', 'any',
             'not', 'ipttl', '42')
        def do_wait():
            while 1:
                r,w,x = select.select([sys.stdin, divertsock], [], [])
                if divertsock in r:
                    _handle_diversion(divertsock, dnsport)
                if sys.stdin in r:
                    return
    else:
        do_wait = None
    return do_wait
 def program_exists(name):
    paths = (os.getenv('PATH') or os.defpath).split(os.pathsep)
    for p in paths:
        fn = '%s/%s' % (p, name)
        if os.path.exists(fn):
            return not os.path.isdir(fn) and os.access(fn, os.X_OK)
 hostmap = {}
 def rewrite_etc_hosts(port):
    HOSTSFILE='/etc/hosts'
    BAKFILE='%s.sbak' % HOSTSFILE
    APPEND='# sshuttle-firewall-%d AUTOCREATED' % port
    old_content = ''
    st = None
    try:
        old_content = open(HOSTSFILE).read()
        st = os.stat(HOSTSFILE)
    except IOError, e:
        if e.errno == errno.ENOENT:
            pass
        else:
            raise
    if old_content.strip() and not os.path.exists(BAKFILE):
        os.link(HOSTSFILE, BAKFILE)
    tmpname = "%s.%d.tmp" % (HOSTSFILE, port)
    f = open(tmpname, 'w')
    for line in old_content.rstrip().split('\n'):
        if line.find(APPEND) >= 0:
            continue
        f.write('%s\n' % line)
    for (name,ip) in sorted(hostmap.items()):
        f.write('%-30s %s\n' % ('%s %s' % (ip,name), APPEND))
    f.close()
    if st:
        os.chown(tmpname, st.st_uid, st.st_gid)
        os.chmod(tmpname, st.st_mode)
    else:
        os.chown(tmpname, 0, 0)
        os.chmod(tmpname, 0644)
    os.rename(tmpname, HOSTSFILE)
 def restore_etc_hosts(port):
    global hostmap
    hostmap = {}
    rewrite_etc_hosts(port)
 # This is some voodoo for setting up the kernel's transparent
 # proxying stuff.  If subnets is empty, we just delete our sshuttle rules;
 # otherwise we delete it, then make them from scratch.
 #
 # This code is supposed to clean up after itself by deleting its rules on
 # exit.  In case that fails, it's not the end of the world; future runs will
 # supercede it in the transproxy list, at least, so the leftover rules
 # are hopefully harmless.
 def main(port, dnsport, syslog):
    assert(port > 0)
    assert(port <= 65535)
    assert(dnsport >= 0)
    assert(dnsport <= 65535)
    if os.getuid() != 0:
        raise Fatal('you must be root (or enable su/sudo) to set the firewall')
    if program_exists('ipfw'):
        do_it = do_ipfw
    elif program_exists('iptables'):
        do_it = do_iptables
    else:
        raise Fatal("can't find either ipfw or iptables; check your PATH")
    # because of limitations of the 'su' command, the *real* stdin/stdout
    # are both attached to stdout initially.  Clone stdout into stdin so we
    # can read from it.
    os.dup2(1, 0)
    if syslog:
        ssyslog.start_syslog()
        ssyslog.stderr_to_syslog()
    debug1('firewall manager ready.\n')
    sys.stdout.write('READY\n')
    sys.stdout.flush()
    # don't disappear if our controlling terminal or stdout/stderr
    # disappears; we still have to clean up.
    signal.signal(signal.SIGHUP, signal.SIG_IGN)
    signal.signal(signal.SIGPIPE, signal.SIG_IGN)
    signal.signal(signal.SIGTERM, signal.SIG_IGN)
    signal.signal(signal.SIGINT, signal.SIG_IGN)
    # ctrl-c shouldn't be passed along to me.  When the main sshuttle dies,
    # I'll die automatically.
    os.setsid()
    # we wait until we get some input before creating the rules.  That way,
    # sshuttle can launch us as early as possible (and get sudo password
    # authentication as early in the startup process as possible).
    line = sys.stdin.readline(128)
    if not line:
        return  # parent died; nothing to do
    subnets = []
    if line != 'ROUTES\n':
        raise Fatal('firewall: expected ROUTES but got %r' % line)
    while 1:
        line = sys.stdin.readline(128)
        if not line:
            raise Fatal('firewall: expected route but got %r' % line)
        elif line == 'GO\n':
            break
        try:
            (width,exclude,ip) = line.strip().split(',', 2)
        except:
            raise Fatal('firewall: expected route or GO but got %r' % line)
        subnets.append((int(width), bool(int(exclude)), ip))
    try:
        if line:
            debug1('firewall manager: starting transproxy.\n')
            do_wait = do_it(port, dnsport, subnets)
            sys.stdout.write('STARTED\n')
        try:
            sys.stdout.flush()
        except IOError:
            # the parent process died for some reason; he's surely been loud
            # enough, so no reason to report another error
            return
        # Now we wait until EOF or any other kind of exception.  We need
        # to stay running so that we don't need a *second* password
        # authentication at shutdown time - that cleanup is important!
        while 1:
            if do_wait: do_wait()
            line = sys.stdin.readline(128)
            if line.startswith('HOST '):
                (name,ip) = line[5:].strip().split(',', 1)
                hostmap[name] = ip
                rewrite_etc_hosts(port)
            elif line:
                raise Fatal('expected EOF, got %r' % line)
            else:
                break
    finally:
        try:
            debug1('firewall manager: undoing changes.\n')
        except:
            pass
        do_it(port, 0, [])
        restore_etc_hosts(port)
--- a/flake.lock
+++ b/flake.lock
@ -1,133 +0,0 @@
 {
  "nodes": {
    "flake-utils": {
      "inputs": {
        "systems": "systems"
      },
      "locked": {
        "lastModified": 1731533236,
        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
        "owner": "numtide",
        "repo": "flake-utils",
        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
        "type": "github"
      },
      "original": {
        "owner": "numtide",
        "repo": "flake-utils",
        "type": "github"
      }
    },
    "nixpkgs": {
      "locked": {
        "lastModified": 1740743217,
        "narHash": "sha256-brsCRzLqimpyhORma84c3W2xPbIidZlIc3JGIuQVSNI=",
        "owner": "NixOS",
        "repo": "nixpkgs",
        "rev": "b27ba4eb322d9d2bf2dc9ada9fd59442f50c8d7c",
        "type": "github"
      },
      "original": {
        "owner": "NixOS",
        "ref": "nixos-24.11",
        "repo": "nixpkgs",
        "type": "github"
      }
    },
    "pyproject-build-systems": {
      "inputs": {
        "nixpkgs": [
          "nixpkgs"
        ],
        "pyproject-nix": [
          "pyproject-nix"
        ],
        "uv2nix": [
          "uv2nix"
        ]
      },
      "locked": {
        "lastModified": 1740362541,
        "narHash": "sha256-S8Mno07MspggOv/xIz5g8hB2b/C5HPiX8E+rXzKY+5U=",
        "owner": "pyproject-nix",
        "repo": "build-system-pkgs",
        "rev": "e151741c848ba92331af91f4e47640a1fb82be19",
        "type": "github"
      },
      "original": {
        "owner": "pyproject-nix",
        "repo": "build-system-pkgs",
        "type": "github"
      }
    },
    "pyproject-nix": {
      "inputs": {
        "nixpkgs": [
          "nixpkgs"
        ]
      },
      "locked": {
        "lastModified": 1739758351,
        "narHash": "sha256-Aoa4dEoC7Hf6+gFVk/SDquZTMFlmlfsgdTWuqQxzePs=",
        "owner": "pyproject-nix",
        "repo": "pyproject.nix",
        "rev": "1329712f7f9af3a8b270764ba338a455b7323811",
        "type": "github"
      },
      "original": {
        "owner": "pyproject-nix",
        "repo": "pyproject.nix",
        "type": "github"
      }
    },
    "root": {
      "inputs": {
        "flake-utils": "flake-utils",
        "nixpkgs": "nixpkgs",
        "pyproject-build-systems": "pyproject-build-systems",
        "pyproject-nix": "pyproject-nix",
        "uv2nix": "uv2nix"
      }
    },
    "systems": {
      "locked": {
        "lastModified": 1681028828,
        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
        "owner": "nix-systems",
        "repo": "default",
        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
        "type": "github"
      },
      "original": {
        "owner": "nix-systems",
        "repo": "default",
        "type": "github"
      }
    },
    "uv2nix": {
      "inputs": {
        "nixpkgs": [
          "nixpkgs"
        ],
        "pyproject-nix": [
          "pyproject-nix"
        ]
      },
      "locked": {
        "lastModified": 1740497536,
        "narHash": "sha256-K+8wsVooqhaqyxuvew3+62mgOfRLJ7whv7woqPU3Ypo=",
        "owner": "pyproject-nix",
        "repo": "uv2nix",
        "rev": "d01fd3a141755ad5d5b93dd9fcbd76d6401f5bac",
        "type": "github"
      },
      "original": {
        "owner": "pyproject-nix",
        "repo": "uv2nix",
        "type": "github"
      }
    }
  },
  "root": "root",
  "version": 7
 }
--- a/flake.nix
+++ b/flake.nix
@ -1,117 +0,0 @@
 {
  description = "Transparent proxy server that works as a poor man's VPN. Forwards over ssh. Doesn't require admin. Works with Linux and MacOS. Supports DNS tunneling.";
  inputs = {
    flake-utils.url = "github:numtide/flake-utils";
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.11";
    pyproject-nix = {
      url = "github:pyproject-nix/pyproject.nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    uv2nix = {
      url = "github:pyproject-nix/uv2nix";
      inputs.pyproject-nix.follows = "pyproject-nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    pyproject-build-systems = {
      url = "github:pyproject-nix/build-system-pkgs";
      inputs.pyproject-nix.follows = "pyproject-nix";
      inputs.uv2nix.follows = "uv2nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };
  outputs =
    {
      self,
      nixpkgs,
      flake-utils,
      pyproject-nix,
      uv2nix,
      pyproject-build-systems,
    }:
    flake-utils.lib.eachDefaultSystem (
      system:
      let
        inherit (nixpkgs) lib;
        pkgs = nixpkgs.legacyPackages.${system};
        python = pkgs.python312;
        workspace = uv2nix.lib.workspace.loadWorkspace { workspaceRoot = ./.; };
        # Create package overlay from workspace.
        overlay = workspace.mkPyprojectOverlay {
          sourcePreference = "sdist";
        };
        # Extend generated overlay with build fixups
        #
        # Uv2nix can only work with what it has, and uv.lock is missing essential metadata to perform some builds.
        # This is an additional overlay implementing build fixups.
        # See:
        # - https://pyproject-nix.github.io/uv2nix/FAQ.html
        pyprojectOverrides =
          final: prev:
          # Implement build fixups here.
          # Note that uv2nix is _not_ using Nixpkgs buildPythonPackage.
          # It's using https://pyproject-nix.github.io/pyproject.nix/build.html
          let
            inherit (final) resolveBuildSystem;
            inherit (builtins) mapAttrs;
            # Build system dependencies specified in the shape expected by resolveBuildSystem
            # The empty lists below are lists of optional dependencies.
            #
            # A package `foo` with specification written as:
            # `setuptools-scm[toml]` in pyproject.toml would be written as
            # `foo.setuptools-scm = [ "toml" ]` in Nix
            buildSystemOverrides = {
              chardet.setuptools = [ ];
              colorlog.setuptools = [ ];
              python-debian.setuptools = [ ];
              pluggy.setuptools = [ ];
              pathspec.flit-core = [ ];
              packaging.flit-core = [ ];
            };
          in
          mapAttrs (
            name: spec:
            prev.${name}.overrideAttrs (old: {
              nativeBuildInputs = old.nativeBuildInputs ++ resolveBuildSystem spec;
            })
          ) buildSystemOverrides;
        pythonSet =
          (pkgs.callPackage pyproject-nix.build.packages {
            inherit python;
          }).overrideScope
            (
              lib.composeManyExtensions [
                pyproject-build-systems.overlays.default
                overlay
                pyprojectOverrides
              ]
            );
        inherit (pkgs.callPackages pyproject-nix.build.util { }) mkApplication;
        package = mkApplication {
          venv = pythonSet.mkVirtualEnv "sshuttle" workspace.deps.default;
          package = pythonSet.sshuttle;
        };
      in
      {
        packages = {
          sshuttle = package;
          default = package;
        };
        devShells.default = pkgs.mkShell {
          packages = [
            pkgs.uv
          ];
        };
      }
    );
 }
--- a/helpers.py
+++ b/helpers.py
@ -0,0 +1,80 @@
 import sys, os, socket, errno
 logprefix = ''
 verbose = 0
 def log(s):
    try:
        sys.stdout.flush()
        sys.stderr.write(logprefix + s)
        sys.stderr.flush()
    except IOError:
        # this could happen if stderr gets forcibly disconnected, eg. because
        # our tty closes.  That sucks, but it's no reason to abort the program.
        pass
 def debug1(s):
    if verbose >= 1:
        log(s)
 def debug2(s):
    if verbose >= 2:
        log(s)
 def debug3(s):
    if verbose >= 3:
        log(s)
 class Fatal(Exception):
    pass
 EXITCODE_NEEDS_REBOOT = 111
 class FatalNeedsReboot(Fatal):
    pass
 def list_contains_any(l, sub):
    for i in sub:
        if i in l:
            return True
    return False
 def resolvconf_nameservers():
    l = []
    for line in open('/etc/resolv.conf'):
        words = line.lower().split()
        if len(words) >= 2 and words[0] == 'nameserver':
            l.append(words[1])
    return l
 def resolvconf_random_nameserver():
    l = resolvconf_nameservers()
    if l:
        if len(l) > 1:
            # don't import this unless we really need it
            import random
            random.shuffle(l)
        return l[0]
    else:
        return '127.0.0.1'
 def islocal(ip):
    sock = socket.socket()
    try:
        try:
            sock.bind((ip, 0))
        except socket.error, e:
            if e.args[0] == errno.EADDRNOTAVAIL:
                return False  # not a local IP
            else:
                raise
    finally:
        sock.close()
    return True  # it's a local IP, or there would have been an error
--- a/hostwatch.py
+++ b/hostwatch.py
@ -0,0 +1,281 @@
 import time, socket, re, select, errno
 if not globals().get('skip_imports'):
    import compat.ssubprocess as ssubprocess
    import helpers
    from helpers import *
 POLL_TIME = 60*15
 NETSTAT_POLL_TIME = 30
 CACHEFILE=os.path.expanduser('~/.sshuttle.hosts')
 _nmb_ok = True
 _smb_ok = True
 hostnames = {}
 queue = {}
 try:
    null = open('/dev/null', 'wb')
 except IOError, e:
    log('warning: %s\n' % e)
    null = os.popen("sh -c 'while read x; do :; done'", 'wb', 4096)
 def _is_ip(s):
    return re.match(r'\d+\.\d+\.\d+\.\d+$', s)
 def write_host_cache():
    tmpname = '%s.%d.tmp' % (CACHEFILE, os.getpid())
    try:
        f = open(tmpname, 'wb')
        for name,ip in sorted(hostnames.items()):
            f.write('%s,%s\n' % (name, ip))
        f.close()
        os.rename(tmpname, CACHEFILE)
    finally:
        try:
            os.unlink(tmpname)
        except:
            pass
 def read_host_cache():
    try:
        f = open(CACHEFILE)
    except IOError, e:
        if e.errno == errno.ENOENT:
            return
        else:
            raise
    for line in f:
        words = line.strip().split(',')
        if len(words) == 2:
            (name,ip) = words
            name = re.sub(r'[^-\w]', '-', name).strip()
            ip = re.sub(r'[^0-9.]', '', ip).strip()
            if name and ip:
                found_host(name, ip)
 def found_host(hostname, ip):
    hostname = re.sub(r'\..*', '', hostname)
    hostname = re.sub(r'[^-\w]', '_', hostname)
    if (ip.startswith('127.') or ip.startswith('255.') 
        or hostname == 'localhost'):
        return
    oldip = hostnames.get(hostname)
    if oldip != ip:
        hostnames[hostname] = ip
        debug1('Found: %s: %s\n' % (hostname, ip))
        sys.stdout.write('%s,%s\n' % (hostname, ip))
        write_host_cache()
 def _check_etc_hosts():
    debug2(' > hosts\n')
    for line in open('/etc/hosts'):
        line = re.sub(r'#.*', '', line)
        words = line.strip().split()
        if not words:
            continue
        ip = words[0]
        names = words[1:]
        if _is_ip(ip):
            debug3('<    %s %r\n' % (ip, names))
            for n in names:
                check_host(n)
                found_host(n, ip)
 def _check_revdns(ip):
    debug2(' > rev: %s\n' % ip)
    try:
        r = socket.gethostbyaddr(ip)
        debug3('<    %s\n' % r[0])
        check_host(r[0])
        found_host(r[0], ip)
    except socket.herror, e:
        pass
 def _check_dns(hostname):
    debug2(' > dns: %s\n' % hostname)
    try:
        ip = socket.gethostbyname(hostname)
        debug3('<    %s\n' % ip)
        check_host(ip)
        found_host(hostname, ip)
    except socket.gaierror, e:
        pass
 def _check_netstat():
    debug2(' > netstat\n')
    argv = ['netstat', '-n']
    try:
        p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, stderr=null)
        content = p.stdout.read()
        p.wait()
    except OSError, e:
        log('%r failed: %r\n' % (argv, e))
        return
    for ip in re.findall(r'\d+\.\d+\.\d+\.\d+', content):
        debug3('<    %s\n' % ip)
        check_host(ip)
 def _check_smb(hostname):
    return
    global _smb_ok
    if not _smb_ok:
        return
    argv = ['smbclient', '-U', '%', '-L', hostname]
    debug2(' > smb: %s\n' % hostname)
    try:
        p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, stderr=null)
        lines = p.stdout.readlines()
        p.wait()
    except OSError, e:
        log('%r failed: %r\n' % (argv, e))
        _smb_ok = False
        return
    lines.reverse()
    # junk at top
    while lines:
        line = lines.pop().strip()
        if re.match(r'Server\s+', line):
            break
    # server list section:
    #    Server   Comment
    #    ------   -------
    while lines:
        line = lines.pop().strip()
        if not line or re.match(r'-+\s+-+', line):
            continue
        if re.match(r'Workgroup\s+Master', line):
            break
        words = line.split()
        hostname = words[0].lower()
        debug3('<    %s\n' % hostname)
        check_host(hostname)
    # workgroup list section:
    #   Workgroup  Master
    #   ---------  ------
    while lines:
        line = lines.pop().strip()
        if re.match(r'-+\s+', line):
            continue
        if not line:
            break
        words = line.split()
        (workgroup, hostname) = (words[0].lower(), words[1].lower())
        debug3('<    group(%s) -> %s\n' % (workgroup, hostname))
        check_host(hostname)
        check_workgroup(workgroup)
    if lines:
        assert(0)
 def _check_nmb(hostname, is_workgroup, is_master):
    return
    global _nmb_ok
    if not _nmb_ok:
        return
    argv = ['nmblookup'] + ['-M']*is_master + ['--', hostname]
    debug2(' > n%d%d: %s\n' % (is_workgroup, is_master, hostname))
    try:
        p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, stderr=null)
        lines = p.stdout.readlines()
        rv = p.wait()
    except OSError, e:
        log('%r failed: %r\n' % (argv, e))
        _nmb_ok = False
        return
    if rv:
        log('%r returned %d\n' % (argv, rv))
        return
    for line in lines:
        m = re.match(r'(\d+\.\d+\.\d+\.\d+) (\w+)<\w\w>\n', line)
        if m:
            g = m.groups()
            (ip, name) = (g[0], g[1].lower())
            debug3('<    %s -> %s\n' % (name, ip))
            if is_workgroup:
                _enqueue(_check_smb, ip)
            else:
                found_host(name, ip)
                check_host(name)
 def check_host(hostname):
    if _is_ip(hostname):
        _enqueue(_check_revdns, hostname)
    else:
        _enqueue(_check_dns, hostname)
    _enqueue(_check_smb, hostname)
    _enqueue(_check_nmb, hostname, False, False)
 def check_workgroup(hostname):
    _enqueue(_check_nmb, hostname, True, False)
    _enqueue(_check_nmb, hostname, True, True)
 def _enqueue(op, *args):
    t = (op,args)
    if queue.get(t) == None:
        queue[t] = 0
 def _stdin_still_ok(timeout):
    r,w,x = select.select([sys.stdin.fileno()], [], [], timeout)
    if r:
        b = os.read(sys.stdin.fileno(), 4096)
        if not b:
            return False
    return True
 def hw_main(seed_hosts):
    if helpers.verbose >= 2:
        helpers.logprefix = 'HH: '
    else:
        helpers.logprefix = 'hostwatch: '
    read_host_cache()
    _enqueue(_check_etc_hosts)
    _enqueue(_check_netstat)
    check_host('localhost')
    check_host(socket.gethostname())
    check_workgroup('workgroup')
    check_workgroup('-')
    for h in seed_hosts:
        check_host(h)
    while 1:
        now = time.time()
        for t,last_polled in queue.items():
            (op,args) = t
            if not _stdin_still_ok(0):
                break
            maxtime = POLL_TIME
            if op == _check_netstat:
                maxtime = NETSTAT_POLL_TIME
            if now - last_polled > maxtime:
                queue[t] = time.time()
                op(*args)
            try:
                sys.stdout.flush()
            except IOError:
                break
        # FIXME: use a smarter timeout based on oldest last_polled
        if not _stdin_still_ok(1):
            break
--- a/main.py
+++ b/main.py
@ -0,0 +1,141 @@
 import sys, os, re
 import helpers, options, client, server, firewall, hostwatch
 import compat.ssubprocess as ssubprocess
 from helpers import *
 # list of:
 # 1.2.3.4/5 or just 1.2.3.4
 def parse_subnets(subnets_str):
    subnets = []
    for s in subnets_str:
        m = re.match(r'(\d+)(?:\.(\d+)\.(\d+)\.(\d+))?(?:/(\d+))?$', s)
        if not m:
            raise Fatal('%r is not a valid IP subnet format' % s)
        (a,b,c,d,width) = m.groups()
        (a,b,c,d) = (int(a or 0), int(b or 0), int(c or 0), int(d or 0))
        if width == None:
            width = 32
        else:
            width = int(width)
        if a > 255 or b > 255 or c > 255 or d > 255:
            raise Fatal('%d.%d.%d.%d has numbers > 255' % (a,b,c,d))
        if width > 32:
            raise Fatal('*/%d is greater than the maximum of 32' % width)
        subnets.append(('%d.%d.%d.%d' % (a,b,c,d), width))
    return subnets
 # 1.2.3.4:567 or just 1.2.3.4 or just 567
 def parse_ipport(s):
    s = str(s)
    m = re.match(r'(?:(\d+)\.(\d+)\.(\d+)\.(\d+))?(?::)?(?:(\d+))?$', s)
    if not m:
        raise Fatal('%r is not a valid IP:port format' % s)
    (a,b,c,d,port) = m.groups()
    (a,b,c,d,port) = (int(a or 0), int(b or 0), int(c or 0), int(d or 0),
                      int(port or 0))
    if a > 255 or b > 255 or c > 255 or d > 255:
        raise Fatal('%d.%d.%d.%d has numbers > 255' % (a,b,c,d))
    if port > 65535:
        raise Fatal('*:%d is greater than the maximum of 65535' % port)
    if a == None:
        a = b = c = d = 0
    return ('%d.%d.%d.%d' % (a,b,c,d), port)
 optspec = """
 sshuttle [-l [ip:]port] [-r [username@]sshserver[:port]] <subnets...>
 sshuttle --server
 sshuttle --firewall <port> <subnets...>
 sshuttle --hostwatch
 --
 l,listen=  transproxy to this ip address and port number [127.0.0.1:0]
 H,auto-hosts scan for remote hostnames and update local /etc/hosts
 N,auto-nets  automatically determine subnets to route
 dns        capture local DNS requests and forward to the remote DNS server
 python=    path to python interpreter on the remote server
 r,remote=  ssh hostname (and optional username) of remote sshuttle server
 x,exclude= exclude this subnet (can be used more than once)
 exclude-from=  exclude the subnets in a file (whitespace separated)
 v,verbose  increase debug message verbosity
 e,ssh-cmd= the command to use to connect to the remote [ssh]
 seed-hosts= with -H, use these hostnames for initial scan (comma-separated)
 no-latency-control  sacrifice latency to improve bandwidth benchmarks
 wrap=      restart counting channel numbers after this number (for testing)
 D,daemon   run in the background as a daemon
 V,version  print sshuttle's version number
 syslog     send log messages to syslog (default if you use --daemon)
 pidfile=   pidfile name (only if using --daemon) [./sshuttle.pid]
 server     (internal use only)
 firewall   (internal use only)
 hostwatch  (internal use only)
 """
 o = options.Options(optspec)
 (opt, flags, extra) = o.parse(sys.argv[2:])
 if opt.version:
    import version
    print version.TAG
    sys.exit(0)
 if opt.daemon:
    opt.syslog = 1
 if opt.wrap:
    import ssnet
    ssnet.MAX_CHANNEL = int(opt.wrap)
 helpers.verbose = opt.verbose
 try:
    if opt.server:
        if len(extra) != 0:
            o.fatal('no arguments expected')
        server.latency_control = opt.latency_control
        sys.exit(server.main())
    elif opt.firewall:
        if len(extra) != 2:
            o.fatal('exactly two arguments expected')
        sys.exit(firewall.main(int(extra[0]), int(extra[1]), opt.syslog))
    elif opt.hostwatch:
        sys.exit(hostwatch.hw_main(extra))
    else:
        if len(extra) < 1 and not opt.auto_nets:
            o.fatal('at least one subnet (or -N) expected')
        includes = extra
        excludes = ['127.0.0.0/8']
        for k,v in flags:
            if k in ('-x','--exclude'):
                excludes.append(v)
            if k in ('-X', '--exclude-from'):
                excludes += open(v).read().split()
        remotename = opt.remote
        if remotename == '' or remotename == '-':
            remotename = None
        if opt.seed_hosts and not opt.auto_hosts:
            o.fatal('--seed-hosts only works if you also use -H')
        if opt.seed_hosts:
            sh = re.split(r'[\s,]+', (opt.seed_hosts or "").strip())
        elif opt.auto_hosts:
            sh = []
        else:
            sh = None
        sys.exit(client.main(parse_ipport(opt.listen or '0.0.0.0:0'),
                             opt.ssh_cmd,
                             remotename,
                             opt.python,
                             opt.latency_control,
                             opt.dns,
                             sh,
                             opt.auto_nets,
                             parse_subnets(includes),
                             parse_subnets(excludes),
                             opt.syslog, opt.daemon, opt.pidfile))
 except FatalNeedsReboot, e:
    log('You must reboot before using sshuttle.\n')
    sys.exit(EXITCODE_NEEDS_REBOOT)
 except Fatal, e:
    log('fatal: %s\n' % e)
    sys.exit(99)
 except KeyboardInterrupt:
    log('\n')
    log('Keyboard interrupt: exiting.\n')
    sys.exit(1)
--- a/options.py
+++ b/options.py
@ -0,0 +1,200 @@
 """Command-line options parser.
 With the help of an options spec string, easily parse command-line options.
 """
 import sys, os, textwrap, getopt, re, struct
 class OptDict:
    def __init__(self):
        self._opts = {}
    def __setitem__(self, k, v):
        if k.startswith('no-') or k.startswith('no_'):
            k = k[3:]
            v = not v
        self._opts[k] = v
    def __getitem__(self, k):
        if k.startswith('no-') or k.startswith('no_'):
            return not self._opts[k[3:]]
        return self._opts[k]
    def __getattr__(self, k):
        return self[k]
 def _default_onabort(msg):
    sys.exit(97)
 def _intify(v):
    try:
        vv = int(v or '')
        if str(vv) == v:
            return vv
    except ValueError:
        pass
    return v
 def _atoi(v):
    try:
        return int(v or 0)
    except ValueError:
        return 0
 def _remove_negative_kv(k, v):
    if k.startswith('no-') or k.startswith('no_'):
        return k[3:], not v
    return k,v
 def _remove_negative_k(k):
    return _remove_negative_kv(k, None)[0]
 def _tty_width():
    s = struct.pack("HHHH", 0, 0, 0, 0)
    try:
        import fcntl, termios
        s = fcntl.ioctl(sys.stderr.fileno(), termios.TIOCGWINSZ, s)
    except (IOError, ImportError):
        return _atoi(os.environ.get('WIDTH')) or 70
    (ysize,xsize,ypix,xpix) = struct.unpack('HHHH', s)
    return xsize or 70
 class Options:
    """Option parser.
    When constructed, two strings are mandatory. The first one is the command
    name showed before error messages. The second one is a string called an
    optspec that specifies the synopsis and option flags and their description.
    For more information about optspecs, consult the bup-options(1) man page.
    Two optional arguments specify an alternative parsing function and an
    alternative behaviour on abort (after having output the usage string).
    By default, the parser function is getopt.gnu_getopt, and the abort
    behaviour is to exit the program.
    """
    def __init__(self, optspec, optfunc=getopt.gnu_getopt,
                 onabort=_default_onabort):
        self.optspec = optspec
        self._onabort = onabort
        self.optfunc = optfunc
        self._aliases = {}
        self._shortopts = 'h?'
        self._longopts = ['help']
        self._hasparms = {}
        self._defaults = {}
        self._usagestr = self._gen_usage()
    def _gen_usage(self):
        out = []
        lines = self.optspec.strip().split('\n')
        lines.reverse()
        first_syn = True
        while lines:
            l = lines.pop()
            if l == '--': break
            out.append('%s: %s\n' % (first_syn and 'usage' or '   or', l))
            first_syn = False
        out.append('\n')
        last_was_option = False
        while lines:
            l = lines.pop()
            if l.startswith(' '):
                out.append('%s%s\n' % (last_was_option and '\n' or '',
                                       l.lstrip()))
                last_was_option = False
            elif l:
                (flags, extra) = l.split(' ', 1)
                extra = extra.strip()
                if flags.endswith('='):
                    flags = flags[:-1]
                    has_parm = 1
                else:
                    has_parm = 0
                g = re.search(r'\[([^\]]*)\]$', extra)
                if g:
                    defval = g.group(1)
                else:
                    defval = None
                flagl = flags.split(',')
                flagl_nice = []
                for _f in flagl:
                    f,dvi = _remove_negative_kv(_f, _intify(defval))
                    self._aliases[f] = _remove_negative_k(flagl[0])
                    self._hasparms[f] = has_parm
                    self._defaults[f] = dvi
                    if len(f) == 1:
                        self._shortopts += f + (has_parm and ':' or '')
                        flagl_nice.append('-' + f)
                    else:
                        f_nice = re.sub(r'\W', '_', f)
                        self._aliases[f_nice] = _remove_negative_k(flagl[0])
                        self._longopts.append(f + (has_parm and '=' or ''))
                        self._longopts.append('no-' + f)
                        flagl_nice.append('--' + _f)
                flags_nice = ', '.join(flagl_nice)
                if has_parm:
                    flags_nice += ' ...'
                prefix = '    %-20s  ' % flags_nice
                argtext = '\n'.join(textwrap.wrap(extra, width=_tty_width(),
                                                initial_indent=prefix,
                                                subsequent_indent=' '*28))
                out.append(argtext + '\n')
                last_was_option = True
            else:
                out.append('\n')
                last_was_option = False
        return ''.join(out).rstrip() + '\n'
    def usage(self, msg=""):
        """Print usage string to stderr and abort."""
        sys.stderr.write(self._usagestr)
        e = self._onabort and self._onabort(msg) or None
        if e:
            raise e
    def fatal(self, s):
        """Print an error message to stderr and abort with usage string."""
        msg = 'error: %s\n' % s
        sys.stderr.write(msg)
        return self.usage(msg)
    def parse(self, args):
        """Parse a list of arguments and return (options, flags, extra).
        In the returned tuple, "options" is an OptDict with known options,
        "flags" is a list of option flags that were used on the command-line,
        and "extra" is a list of positional arguments.
        """
        try:
            (flags,extra) = self.optfunc(args, self._shortopts, self._longopts)
        except getopt.GetoptError, e:
            self.fatal(e)
        opt = OptDict()
        for k,v in self._defaults.iteritems():
            k = self._aliases[k]
            opt[k] = v
        for (k,v) in flags:
            k = k.lstrip('-')
            if k in ('h', '?', 'help'):
                self.usage()
            if k.startswith('no-'):
                k = self._aliases[k[3:]]
                v = 0
            else:
                k = self._aliases[k]
                if not self._hasparms[k]:
                    assert(v == '')
                    v = (opt._opts.get(k) or 0) + 1
                else:
                    v = _intify(v)
            opt[k] = v
        for (f1,f2) in self._aliases.iteritems():
            opt[f1] = opt._opts.get(f2)
        return (opt,flags,extra)
--- a/pyproject.toml
+++ b/pyproject.toml
@ -1,57 +0,0 @@
 [project]
 authors = [
    {name = "Brian May", email = "brian@linuxpenguins.xyz"},
 ]
 license = {text = "LGPL-2.1"}
 requires-python = "<4.0,>=3.9"
 dependencies = []
 name = "sshuttle"
 version = "1.3.1"
 description = "Transparent proxy server that works as a poor man's VPN. Forwards over ssh. Doesn't require admin. Works with Linux and MacOS. Supports DNS tunneling."
 readme = "README.rst"
 classifiers = [
    "Development Status :: 5 - Production/Stable",
    "Intended Audience :: Developers",
    "Intended Audience :: End Users/Desktop",
    "License :: OSI Approved :: GNU Lesser General Public License v2 or later (LGPLv2+)",
    "Operating System :: OS Independent",
    "Programming Language :: Python :: 3.9",
    "Programming Language :: Python :: 3.10",
    "Programming Language :: Python :: 3.11",
    "Programming Language :: Python :: 3.12",
    "Topic :: System :: Networking",
 ]
 [project.scripts]
 sshuttle = "sshuttle.cmdline:main"
 [dependency-groups]
 dev = [
    "pytest<9.0.0,>=8.0.1",
    "pytest-cov<7.0,>=4.1",
    "flake8<8.0.0,>=7.0.0",
    "pyflakes<4.0.0,>=3.2.0",
    "bump2version<2.0.0,>=1.0.1",
    "twine<7,>=5",
    "black>=25.1.0",
    "jedi-language-server>=0.44.0",
    "pylsp-mypy>=0.7.0",
    "python-lsp-server>=1.12.2",
    "ruff>=0.11.2",
 ]
 docs = [
    "sphinx==8.1.3; python_version ~= \"3.10\"",
    "furo==2024.8.6",
 ]
 [tool.uv]
 default-groups = []
 [build-system]
 requires = ["hatchling"]
 build-backend = "hatchling.build"
 [tool.hatch.build.targets.sdist]
 exclude = [
    "/.jj"
 ]
--- a/15
+++ b/15
@ -1,15 +0,0 @@
 #!/usr/bin/env sh
 set -e
 export PYTHONPATH="$(dirname "$0"):$PYTHONPATH"
 export PATH="$(dirname "$0")/bin:$PATH"
 python_best_version() {
  if [ -x "$(command -v python3)" ] &&
      python3 -c "import sys; sys.exit(not sys.version_info > (3, 5))"; then
    exec python3 "$@"
  else
    exec python "$@"
  fi
 }
 python_best_version -m "sshuttle" "$@"
--- a/scripts/Containerfile
+++ b/scripts/Containerfile
@ -1,39 +0,0 @@
 # https://hub.docker.com/r/linuxserver/openssh-server/
 ARG BASE_IMAGE=docker.io/linuxserver/openssh-server:version-9.3_p2-r1
 FROM ${BASE_IMAGE} as pyenv
 # https://github.com/pyenv/pyenv/wiki#suggested-build-environment
 RUN apk add --no-cache build-base git libffi-dev openssl-dev bzip2-dev zlib-dev readline-dev sqlite-dev
 ENV PYENV_ROOT=/pyenv
 RUN curl https://raw.githubusercontent.com/pyenv/pyenv-installer/master/bin/pyenv-installer | bash
 RUN /pyenv/bin/pyenv install 3.10
 RUN /pyenv/bin/pyenv install 3.11
 RUN /pyenv/bin/pyenv install 3.12
 RUN bash -xc 'rm -rf /pyenv/{.git,plugins} /pyenv/versions/*/lib/*/{test,config,config-*linux-gnu}' && \
    find /pyenv -type d -name __pycache__ -exec rm -rf {} + && \
    find /pyenv -type f -name '*.py[co]' -delete
 FROM ${BASE_IMAGE}
 RUN apk add --no-cache bash nginx iperf3
 # pyenv setup
 ENV PYENV_ROOT=/pyenv
 ENV PATH=/pyenv/shims:/pyenv/bin:$PATH
 COPY --from=pyenv /pyenv /pyenv
 # OpenSSH Server variables
 ENV PUID=1000
 ENV PGID=1000
 ENV PASSWORD_ACCESS=true
 ENV USER_NAME=test
 ENV USER_PASSWORD=test
 ENV LOG_STDOUT=true
 # suppress linuxserver.io logo printing, chnage sshd config
 RUN sed -i '1 a exec &>/dev/null' /etc/s6-overlay/s6-rc.d/init-adduser/run
 # https://www.linuxserver.io/blog/2019-09-14-customizing-our-containers
 # To customize the container and start other components 
 COPY container.setup.sh /custom-cont-init.d/setup.sh
--- a/scripts/README.md
+++ b/scripts/README.md
@ -1,21 +0,0 @@
 # Container based test bed for sshuttle
 ```bash
 test-bed up -d # start containers
 exec-sshuttle <node-id> [--copy-id] [--server-py=2.7|3.10] [--client-py=2.7|3.10] [--sshuttle-bin=/path/to/sshuttle] [sshuttle-args...]
    # --copy-id  -> optionally do ssh-copy-id to make it passwordless for future runs
    # --sshuttle-bin -> use another sshuttle binary instead of one from dev setup
    # --server-py  -> Python version to use in server. (manged by pyenv)
    # --client-py -> Python version to use in client (manged by pyenv)
 exec-sshuttle node-1 # start sshuttle to connect to node-1
 exec-tool curl node-1  # curl to nginx instance running on node1 via IP that is only reachable via sshuttle
 exec-tool iperf3 node-1 # measure throughput to node-1
 run-benchmark node-1 --client-py=3.10
 ```
 <https://learn.microsoft.com/en-us/windows-server/administration/openssh/openssh_server_configuration#configuring-the-default-shell-for-openssh-in-windows>
--- a/scripts/compose.yml
+++ b/scripts/compose.yml
@ -1,34 +0,0 @@
 name: sshuttle-testbed
 services:
  node-1:
    image: ghcr.io/sshuttle/sshuttle-testbed
    container_name: sshuttle-testbed-node-1
    hostname: node-1
    cap_add:
      - "NET_ADMIN"
    environment:
      - ADD_IP_ADDRESSES=10.55.1.77/24
    networks:
      default:
        ipv6_address: 2001:0DB8::551
  node-2:
    image: ghcr.io/sshuttle/sshuttle-testbed
    container_name: sshuttle-testbed-node-2
    hostname: node-2
    cap_add:
      - "NET_ADMIN"
    environment:
      - ADD_IP_ADDRESSES=10.55.2.77/32
    networks:
      default:
        ipv6_address: 2001:0DB8::552
 networks:
  default:
    driver: bridge
    enable_ipv6: true
    ipam:
       config:
         - subnet: 2001:0DB8::/112
    # internal: true
--- a/scripts/container.setup.sh
+++ b/scripts/container.setup.sh
@ -1,65 +0,0 @@
 #!/usr/bin/with-contenv bash
 # shellcheck shell=bash
 set -e
 function with_set_x() {
    set -x
    "$@"
    {
        ec=$?
        set +x
        return $ec
    } 2>/dev/null
 }
 function log() {
    echo "$*" >&2
 }
 log ">>> Setting up $(hostname) | id: $(id)\nIP:\n$(ip a)\nRoutes:\n$(ip r)\npyenv:\n$(pyenv versions)"
 echo "
 AcceptEnv PYENV_VERSION
 " >> /etc/ssh/sshd_config
 iface="$(ip route | awk '/default/ { print $5 }')"
 default_gw="$(ip route | awk '/default/ { print $3 }')"
 for addr in ${ADD_IP_ADDRESSES//,/ }; do
    log ">>> Adding $addr to interface $iface"
    net_addr=$(ipcalc -n "$addr" | awk -F= '{print $2}')
    with_set_x ip addr add "$addr" dev "$iface"
    with_set_x ip route add "$net_addr" via "$default_gw" dev "$iface" # so that sshuttle -N can discover routes
 done
 log ">>> Starting iperf3 server"
 iperf3 --server --port 5001 &
 mkdir -p /www
 echo "<h5>Hello from $(hostname)</h5>
 <pre>
 <u>ip address</u>
 $(ip address)
 <u>ip route</u>
 $(ip route)
 </pre>" >/www/index.html
 echo " 
 daemon off;
 worker_processes 1;
 error_log /dev/stdout info;
 events {
    worker_connections 1024;
 }
 http {
    include /etc/nginx/mime.types;
    server {
        access_log /dev/stdout;
        listen 8080 default_server;
        listen [::]:8080 default_server;
        root /www;
    }
 }" >/etc/nginx/nginx.conf
 log ">>> Starting nginx"
 nginx &
--- a/scripts/exec-sshuttle
+++ b/scripts/exec-sshuttle
@ -1,159 +0,0 @@
 #!/usr/bin/env bash
 set -e
 export MSYS_NO_PATHCONV=1
 function with_set_x() {
    set -x
    "$@"
    {
        ec=$?
        set +x
        return $ec
    } 2>/dev/null
 }
 function log() {
    echo "$*" >&2
 }
 ssh_cmd='ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null'
 ssh_copy_id=false
 args=()
 subnet_args=()
 while [[ $# -gt 0 ]]; do
    arg=$1
    shift
    case "$arg" in
    -v|-vv*)
        ssh_cmd+=" -v"
        args+=("$arg")
        ;;
    -r)
        args+=("-r" "$1")
        shift
        ;;
    --copy-id)
        ssh_copy_id=true
        ;;
    --server-py=*)
        server_pyenv_ver="${arg#*=}"
        ;;
    --client-py=*)
        client_pyenv_ver="${arg#*=}"
        ;;
    -6)
        ipv6_only=true
        ;;
    --sshuttle-bin=*)
        sshuttle_bin="${arg#*=}"
        ;;
    -N|*/*)
        subnet_args+=("$arg")
    ;;
    -*) 
        args+=("$arg")
    ;;
    *)
        if  [[ -z "$target" ]]; then
            target=$arg
        else
            args+=("$arg")
        fi
        ;;
    esac
 done
 if [[ ${#subnet_args[@]} -eq 0 ]]; then
    subnet_args=("-N")
 fi
 if [[ $target == node-* ]]; then
    log "Target is a a test-bed node"
    port="2222"
    user_part="test:test"
    host=$("$(dirname "$0")/test-bed" get-ip "$target")
    index=${target#node-}
    if [[ $ipv6_only == true ]]; then
        args+=("2001:0DB8::/112")
    else
        args+=("10.55.$index.0/24")
    fi
    target="$user_part@$host:$port"
    if ! command -v sshpass >/dev/null; then
        log "sshpass is not found. You might have to manually enter ssh password: 'test'"
    fi
    if [[ -z $server_pyenv_ver ]]; then
        log "server-py argumwnt is not specified. Setting it to 3.8"
        server_pyenv_ver="3.8"
    fi
 fi
 if [[ -n $server_pyenv_ver ]]; then
    log "Would pass PYENV_VERRSION=$server_pyenv_ver to server. pyenv is required on server to make it work"
    pycmd="/pyenv/shims/python"
    ssh_cmd+=" -o SetEnv=PYENV_VERSION=${server_pyenv_ver:-'3'}"
    args=("--python=$pycmd" "${args[@]}")
 fi
 if [[ $ssh_copy_id == true ]]; then
    log "Trying to make it passwordless"
    if [[ $target == *@* ]]; then
        user_part="${target%%@*}"
        host_part="${target#*@}"
    else
        user_part="$(whoami)"
        host_part="$target"
    fi
    if [[ $host_part == *:* ]]; then
        host="${host_part%:*}"
        port="${host_part#*:}"
    else
        host="$host_part"
        port="22"
    fi
    if [[ $user_part == *:* ]]; then
        user="${user_part%:*}"
        password="${user_part#*:}"
    else
        user="$user_part"
        password=""
    fi
    cmd=(ssh-copy-id -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -p "$port" "$user@$host")
    if [[ -n $password  ]] && command -v sshpass >/dev/null; then
        cmd=(sshpass -p "$password" "${cmd[@]}")
    fi
    with_set_x "${cmd[@]}"
 fi
 if [[ -z $sshuttle_bin || "$sshuttle_bin" == dev ]]; then
    cd "$(dirname "$0")/.."
    export PYTHONPATH="."
    if [[ -n $client_pyenv_ver ]]; then
        log "Using pyenv version: $client_pyenv_ver"
        command -v pyenv &>/dev/null || log "You have to install pyenv to use --client-py" && exit 1
        sshuttle_cmd=(/usr/bin/env PYENV_VERSION="$client_pyenv_ver" pyenv exec python -m sshuttle)
    else
        log "Using best python version availble"
        if [ -x "$(command -v python3)" ] &&
            python3 -c "import sys; sys.exit(not sys.version_info > (3, 5))"; then
            sshuttle_cmd=(python3 -m sshuttle)
        else
            sshuttle_cmd=(python -m sshuttle)
        fi
    fi
 else
    [[ -n $client_pyenv_ver ]] && log "Can't specify --client-py when --sshuttle-bin is specified" && exit 1
    sshuttle_cmd=("$sshuttle_bin")
 fi
 if [[ " ${args[*]} " != *" --ssh-cmd "* ]]; then
    args=("--ssh-cmd" "$ssh_cmd" "${args[@]}")
 fi
 if [[ " ${args[*]} " != *" -r "* ]]; then
    args=("-r" "$target" "${args[@]}")
 fi
 set -x
 "${sshuttle_cmd[@]}" --version
 exec "${sshuttle_cmd[@]}" "${args[@]}" "${subnet_args[@]}"
--- a/scripts/exec-tool
+++ b/scripts/exec-tool
@ -1,86 +0,0 @@
 #!/usr/bin/env bash
 set -e
 function with_set_x() {
    set -x
    "$@"
    {
        ec=$?
        set +x
        return $ec
    } 2>/dev/null
 }
 function log() {
    echo "$*" >&2
 }
 args=()
 while [[ $# -gt 0 ]]; do
    arg=$1
    shift
    case "$arg" in
    -6)
        ipv6_only=true
        continue
        ;;
    -*) ;;
    *)
        if [[ -z $tool ]]; then
            tool=$arg
            continue
        elif [[ -z $node ]]; then
            node=$arg
            continue
        fi
        ;;
    esac
    args+=("$arg")
 done
 tool=${tool?:"tool argument missing. should be one of iperf3,ping,curl,ab"}
 node=${node?:"node argument missing. should be 'node-1' , 'node-2' etc"}
 if [[ $node == node-* ]]; then
    index=${node#node-}
    if [[ $ipv6_only == true ]]; then
        host="2001:0DB8::55$index"
    else
        host="10.55.$index.77"
    fi
 else
    host=$node
 fi
 connect_timeout_sec=3
 case "$tool" in
 ping)
    with_set_x exec ping -W $connect_timeout_sec "${args[@]}" "$host"
    ;;
 iperf3)
    port=5001
    with_set_x exec iperf3 --client "$host" --port=$port --connect-timeout=$((connect_timeout_sec * 1000)) "${args[@]}"
    ;;
 curl)
    port=8080
    if [[ $host = *:* ]]; then
        host="[$host]"
        args+=(--ipv6)
    fi
    with_set_x exec curl "http://$host:$port/" -v --connect-timeout $connect_timeout_sec "${args[@]}"
    ;;
 ab)
    port=8080
    if [[ " ${args[*]}" != *" -n "* && " ${args[*]}" != *" -c "* ]]; then
        args+=(-n 500 -c 50 "${args[@]}")
    fi
    with_set_x exec ab -s $connect_timeout_sec "${args[@]}" "http://$host:$port/"
    ;;
 *)
    log "Unknown tool: $tool"
    exit 2
    ;;
 esac
--- a/scripts/run-benchmark
+++ b/scripts/run-benchmark
@ -1,40 +0,0 @@
 #!/usr/bin/env bash
 set -e
 cd "$(dirname "$0")"
 function with_set_x() {
    set -x
    "$@"
    {
        ec=$?
        set +x
        return $ec
    } 2>/dev/null
 }
 function log() {
    echo "$*" >&2
 }
 ./test-bed up -d
 benchmark() {
    log -e "\n======== Benchmarking sshuttle | Args: [$*]  ========"
    local node=$1
    shift
    with_set_x ./exec-sshuttle "$node" --listen 55771 "$@" &
    sshuttle_pid=$!
    trap 'kill -0 $sshuttle_pid &>/dev/null && kill -15 $sshuttle_pid' EXIT
    while ! nc -z localhost 55771; do sleep 0.1; done
    sleep 1
    ./exec-tool iperf3 "$node" --time=4
    with_set_x kill -15 $sshuttle_pid
    wait $sshuttle_pid || true
 }
 if [[ $# -gt 0 ]]; then
    benchmark "${@}"
 else
    benchmark node-1 --sshuttle-bin="${SSHUTTLE_BIN:-sshuttle}"
    benchmark node-1 --sshuttle-bin=dev
 fi
--- a/scripts/run-checks
+++ b/scripts/run-checks
@ -1,9 +0,0 @@
 #!/usr/bin/env bash
 set -e
 cd "$(dirname "$0")/.."
 export PYTHONPATH=.
 set -x
 python -m flake8 sshuttle tests 
 python -m pytest .
--- a/scripts/test-bed
+++ b/scripts/test-bed
@ -1,42 +0,0 @@
 #!/usr/bin/env bash
 set -e
 cd "$(dirname "$0")"
 if [[ -z $1 || $1 = -* ]]; then
    set -- up "$@"
 fi
 function with_set_x() {
    set -x
    "$@"
    {
        ec=$?
        set +x
        return $ec
    } 2>/dev/null
 }
 function build() {
    # podman build -t ghcr.io/sshuttle/sshuttle-testbed .
    with_set_x docker build --progress=plain -t ghcr.io/sshuttle/sshuttle-testbed -f Containerfile .
 }
 function compose() {
    # podman-compose "$@"
    with_set_x docker compose "$@"
 }
 function get-ip() {
    local container_name=sshuttle-testbed-"$1"
    docker inspect -f '{{range.NetworkSettings.Networks}}{{.IPAddress}}{{end}}' "$container_name"
 }
 if [[ $1 == get-ip ]]; then
    shift
    get-ip "$@"
 else
    if [[ $* = *--build* ]]; then
        build
    fi
    compose "$@"
 fi
--- a/server.py
+++ b/server.py
@ -0,0 +1,254 @@
 import re, struct, socket, select, traceback, time
 if not globals().get('skip_imports'):
    import ssnet, helpers, hostwatch
    import compat.ssubprocess as ssubprocess
    from ssnet import SockWrapper, Handler, Proxy, Mux, MuxWrapper
    from helpers import *
 def _ipmatch(ipstr):
    if ipstr == 'default':
        ipstr = '0.0.0.0/0'
    m = re.match(r'^(\d+(\.\d+(\.\d+(\.\d+)?)?)?)(?:/(\d+))?$', ipstr)
    if m:
        g = m.groups()
        ips = g[0]
        width = int(g[4] or 32)
        if g[1] == None:
            ips += '.0.0.0'
            width = min(width, 8)
        elif g[2] == None:
            ips += '.0.0'
            width = min(width, 16)
        elif g[3] == None:
            ips += '.0'
            width = min(width, 24)
        return (struct.unpack('!I', socket.inet_aton(ips))[0], width)
 def _ipstr(ip, width):
    if width >= 32:
        return ip
    else:
        return "%s/%d" % (ip, width)
 def _maskbits(netmask):
    if not netmask:
        return 32
    for i in range(32):
        if netmask[0] & _shl(1, i):
            return 32-i
    return 0
 def _shl(n, bits):
    # we use our own implementation of left-shift because
    # results may be different between older and newer versions
    # of python for numbers like 1<<32.  We use long() because
    # int(2**32) doesn't work in older python, which has limited
    # int sizes.
    return n * long(2**bits)
 def _list_routes():
    argv = ['netstat', '-rn']
    p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE)
    routes = []
    for line in p.stdout:
        cols = re.split(r'\s+', line)
        ipw = _ipmatch(cols[0])
        if not ipw:
            continue  # some lines won't be parseable; never mind
        maskw = _ipmatch(cols[2])  # linux only
        mask = _maskbits(maskw)   # returns 32 if maskw is null
        width = min(ipw[1], mask)
        ip = ipw[0] & _shl(_shl(1, width) - 1, 32-width)
        routes.append((socket.inet_ntoa(struct.pack('!I', ip)), width))
    rv = p.wait()
    if rv != 0:
        log('WARNING: %r returned %d\n' % (argv, rv))
        log('WARNING: That prevents --auto-nets from working.\n')
    return routes
 def list_routes():
    l = []
    for (ip,width) in _list_routes():
        if not ip.startswith('0.') and not ip.startswith('127.'):
            l.append((ip,width))
    return l
 def _exc_dump():
    exc_info = sys.exc_info()
    return ''.join(traceback.format_exception(*exc_info))
 def start_hostwatch(seed_hosts):
    s1,s2 = socket.socketpair()
    pid = os.fork()
    if not pid:
        # child
        rv = 99
        try:
            try:
                s2.close()
                os.dup2(s1.fileno(), 1)
                os.dup2(s1.fileno(), 0)
                s1.close()
                rv = hostwatch.hw_main(seed_hosts) or 0
            except Exception, e:
                log('%s\n' % _exc_dump())
                rv = 98
        finally:
            os._exit(rv)
    s1.close()
    return pid,s2
 class Hostwatch:
    def __init__(self):
        self.pid = 0
        self.sock = None
 class DnsProxy(Handler):
    def __init__(self, mux, chan, request):
        sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        Handler.__init__(self, [sock])
        self.timeout = time.time()+30
        self.mux = mux
        self.chan = chan
        self.tries = 0
        self.peer = None
        self.request = request
        self.sock = sock
        self.sock.setsockopt(socket.SOL_IP, socket.IP_TTL, 42)
        self.try_send()
    def try_send(self):
        if self.tries >= 3:
            return
        self.tries += 1
        self.peer = resolvconf_random_nameserver()
        self.sock.connect((self.peer, 53))
        debug2('DNS: sending to %r\n' % self.peer)
        try:
            self.sock.send(self.request)
        except socket.error, e:
            if e.args[0] in ssnet.NET_ERRS:
                # might have been spurious; try again.
                # Note: these errors sometimes are reported by recv(),
                # and sometimes by send().  We have to catch both.
                debug2('DNS send to %r: %s\n' % (self.peer, e))
                self.try_send()
                return
            else:
                log('DNS send to %r: %s\n' % (self.peer, e))
                return
    def callback(self):
        try:
            data = self.sock.recv(4096)
        except socket.error, e:
            if e.args[0] in ssnet.NET_ERRS:
                # might have been spurious; try again.
                # Note: these errors sometimes are reported by recv(),
                # and sometimes by send().  We have to catch both.
                debug2('DNS recv from %r: %s\n' % (self.peer, e))
                self.try_send()
                return
            else:
                log('DNS recv from %r: %s\n' % (self.peer, e))
                return
        debug2('DNS response: %d bytes\n' % len(data))
        self.mux.send(self.chan, ssnet.CMD_DNS_RESPONSE, data)
        self.ok = False
 def main():
    if helpers.verbose >= 1:
        helpers.logprefix = ' s: '
    else:
        helpers.logprefix = 'server: '
    debug1('latency control setting = %r\n' % latency_control)
    routes = list(list_routes())
    debug1('available routes:\n')
    for r in routes:
        debug1('  %s/%d\n' % r)
    # synchronization header
    sys.stdout.write('\0\0SSHUTTLE0001')
    sys.stdout.flush()
    handlers = []
    mux = Mux(socket.fromfd(sys.stdin.fileno(),
                            socket.AF_INET, socket.SOCK_STREAM),
              socket.fromfd(sys.stdout.fileno(),
                            socket.AF_INET, socket.SOCK_STREAM))
    handlers.append(mux)
    routepkt = ''
    for r in routes:
        routepkt += '%s,%d\n' % r
    mux.send(0, ssnet.CMD_ROUTES, routepkt)
    hw = Hostwatch()
    hw.leftover = ''
    def hostwatch_ready():
        assert(hw.pid)
        content = hw.sock.recv(4096)
        if content:
            lines = (hw.leftover + content).split('\n')
            if lines[-1]:
                # no terminating newline: entry isn't complete yet!
                hw.leftover = lines.pop()
                lines.append('')
            else:
                hw.leftover = ''
            mux.send(0, ssnet.CMD_HOST_LIST, '\n'.join(lines))
        else:
            raise Fatal('hostwatch process died')
    def got_host_req(data):
        if not hw.pid:
            (hw.pid,hw.sock) = start_hostwatch(data.strip().split())
            handlers.append(Handler(socks = [hw.sock],
                                    callback = hostwatch_ready))
    mux.got_host_req = got_host_req
    def new_channel(channel, data):
        (dstip,dstport) = data.split(',', 1)
        dstport = int(dstport)
        outwrap = ssnet.connect_dst(dstip,dstport)
        handlers.append(Proxy(MuxWrapper(mux, channel), outwrap))
    mux.new_channel = new_channel
    dnshandlers = {}
    def dns_req(channel, data):
        debug2('Incoming DNS request.\n')
        h = DnsProxy(mux, channel, data)
        handlers.append(h)
        dnshandlers[channel] = h
    mux.got_dns_req = dns_req
    while mux.ok:
        if hw.pid:
            assert(hw.pid > 0)
            (rpid, rv) = os.waitpid(hw.pid, os.WNOHANG)
            if rpid:
                raise Fatal('hostwatch exited unexpectedly: code 0x%04x\n' % rv)
        ssnet.runonce(handlers, mux)
        if latency_control:
            mux.check_fullness()
        mux.callback()
        if dnshandlers:
            now = time.time()
            for channel,h in dnshandlers.items():
                if h.timeout < now or not h.ok:
                    del dnshandlers[channel]
                    h.ok = False
--- a/setup.cfg
+++ b/setup.cfg
@ -1,30 +0,0 @@
 [bumpversion]
 current_version = 1.3.1
 [bumpversion:file:setup.py]
 [bumpversion:file:pyproject.toml]
 [bumpversion:file:sshuttle/version.py]
 [aliases]
 test = pytest
 [bdist_wheel]
 universal = 1
 [upload]
 sign = true
 identity = 0x1784577F811F6EAC
 [flake8]
 count = true
 show-source = true
 statistics = true
 max-line-length = 128
 [pycodestyle]
 max-line-length = 128
 [tool:pytest]
 addopts = --cov=sshuttle --cov-branch --cov-report=term-missing
--- a/ssh.py
+++ b/ssh.py
@ -0,0 +1,106 @@
 import sys, os, re, socket, zlib
 import compat.ssubprocess as ssubprocess
 import helpers
 from helpers import *
 def readfile(name):
    basedir = os.path.dirname(os.path.abspath(sys.argv[0]))
    path = [basedir] + sys.path
    for d in path:
        fullname = os.path.join(d, name)
        if os.path.exists(fullname):
            return open(fullname, 'rb').read()
    raise Exception("can't find file %r in any of %r" % (name, path))
 def empackage(z, filename, data=None):
    (path,basename) = os.path.split(filename)
    if not data:
        data = readfile(filename)
    content = z.compress(data)
    content += z.flush(zlib.Z_SYNC_FLUSH)
    return '%s\n%d\n%s' % (basename, len(content), content)
 def connect(ssh_cmd, rhostport, python, stderr, options):
    main_exe = sys.argv[0]
    portl = []
    rhostIsIPv6 = False
    if (rhostport or '').count(':') > 1:
        rhostIsIPv6 = True
        if rhostport.count(']') or rhostport.count('['):
            result = rhostport.split(']')
            rhost = result[0].strip('[')
            if len(result) > 1:
                result[1] = result[1].strip(':')
                if result[1] is not '':
                    portl = ['-p', str(int(result[1]))]
        else: # can't disambiguate IPv6 colons and a port number. pass the hostname through.
            rhost = rhostport
    else: # IPv4
        l = (rhostport or '').split(':', 1)
        rhost = l[0]
        if len(l) > 1:
            portl = ['-p', str(int(l[1]))]
    if rhost == '-':
        rhost = None
    ipv6flag = []
    if rhostIsIPv6:
        ipv6flag = ['-6']
    z = zlib.compressobj(1)
    content = readfile('assembler.py')
    optdata = ''.join("%s=%r\n" % (k,v) for (k,v) in options.items())
    content2 = (empackage(z, 'cmdline_options.py', optdata) +
                empackage(z, 'helpers.py') +
                empackage(z, 'compat/ssubprocess.py') +
                empackage(z, 'ssnet.py') +
                empackage(z, 'hostwatch.py') +
                empackage(z, 'server.py') +
                "\n")
    pyscript = r"""
                import sys;
                skip_imports=1;
                verbosity=%d;
                exec compile(sys.stdin.read(%d), "assembler.py", "exec")
                """ % (helpers.verbose or 0, len(content))
    pyscript = re.sub(r'\s+', ' ', pyscript.strip())
    if not rhost:
        # ignore the --python argument when running locally; we already know
        # which python version works.
        argv = [sys.argv[1], '-c', pyscript]
    else:
        if ssh_cmd:
            sshl = ssh_cmd.split(' ')
        else:
            sshl = ['ssh']
        if python:
            pycmd = "'%s' -c '%s'" % (python, pyscript)
        else:
            pycmd = ("P=python2; $P -V 2>/dev/null || P=python; "
                     "exec \"$P\" -c '%s'") % pyscript
        argv = (sshl + 
                portl + 
                ipv6flag + 
                [rhost, '--', pycmd])
    (s1,s2) = socket.socketpair()
    def setup():
        # runs in the child process
        s2.close()
    s1a,s1b = os.dup(s1.fileno()), os.dup(s1.fileno())
    s1.close()
    debug2('executing: %r\n' % argv)
    p = ssubprocess.Popen(argv, stdin=s1a, stdout=s1b, preexec_fn=setup,
                          close_fds=True, stderr=stderr)
    os.close(s1a)
    os.close(s1b)
    s2.sendall(content)
    s2.sendall(content2)
    return p, s2
--- a/12
+++ b/12
@ -0,0 +1,12 @@
 #!/bin/sh
 EXE=$0
 for i in 1 2 3 4 5 6 7 8 9 10; do
 	[ -L "$EXE" ] || break
 	EXE=$(readlink "$EXE")
 done
 DIR=$(dirname "$EXE")
 if python2 -V 2>/dev/null; then
 	exec python2 "$DIR/main.py" python2 "$@"
 else
 	exec python "$DIR/main.py" python "$@"
 fi
--- a/sshuttle/init.py
+++ b/sshuttle/init.py
@ -1 +0,0 @@
 __version__ = "1.3.1"
--- a/sshuttle/main.py
+++ b/sshuttle/main.py
@ -1,10 +0,0 @@
 """Coverage.py's main entry point."""
 import sys
 import os
 from sshuttle.cmdline import main
 from sshuttle.helpers import debug3
 debug3("Start: (pid=%s, ppid=%s) %r" % (os.getpid(), os.getppid(), sys.argv))
 exit_code = main()
 debug3("Exit: (pid=%s, ppid=%s, code=%s) cmd %r" % (os.getpid(), os.getppid(), exit_code, sys.argv))
 sys.exit(exit_code)
--- a/sshuttle/assembler.py
+++ b/sshuttle/assembler.py
@ -1,53 +0,0 @@
 import sys
 import zlib
 import types
 import platform
 stdin = stdin  # type: typing.BinaryIO # noqa: F821 must be a previously defined global
 verbosity = verbosity  # type: int # noqa: F821 must be a previously defined global
 if verbosity > 0:
    sys.stderr.write(' s: Running server on remote host with %s (version %s)\n'
                     % (sys.executable, platform.python_version()))
 z = zlib.decompressobj()
 while 1:
    name = stdin.readline().strip()
    if name:
        # python2 compat: in python2 stdin.readline().strip() -> str
        #                 in python3 stdin.readline().strip() -> bytes
        # (see #481)
        if sys.version_info >= (3, 0):
            name = name.decode("ASCII")
        nbytes = int(stdin.readline())
        if verbosity >= 2:
            sys.stderr.write(' s: assembling %r (%d bytes)\n'
                             % (name, nbytes))
        content = z.decompress(stdin.read(nbytes))
        module = types.ModuleType(name)
        parents = name.rsplit(".", 1)
        if len(parents) == 2:
            parent, parent_name = parents
            setattr(sys.modules[parent], parent_name, module)
        code = compile(content, name, "exec")
        exec(code, module.__dict__)  # nosec
        sys.modules[name] = module
    else:
        break
 sys.stderr.flush()
 sys.stdout.flush()
 # import can only happen once the code has been transferred to
 # the server. 'noqa: E402' excludes these lines from QA checks.
 import sshuttle.helpers  # noqa: E402
 sshuttle.helpers.verbose = verbosity
 import sshuttle.cmdline_options as options  # noqa: E402
 from sshuttle.server import main  # noqa: E402
 main(options.latency_control, options.latency_buffer_size,
     options.auto_hosts, options.to_nameserver,
     options.auto_nets)
--- a/sshuttle/client.py
+++ b/sshuttle/client.py
--- a/sshuttle/cmdline.py
+++ b/sshuttle/cmdline.py
@ -1,145 +0,0 @@
 import os
 import re
 import shlex
 import socket
 import sys
 import sshuttle.helpers as helpers
 import sshuttle.client as client
 import sshuttle.firewall as firewall
 import sshuttle.hostwatch as hostwatch
 import sshuttle.ssyslog as ssyslog
 from sshuttle.options import parser, parse_ipport
 from sshuttle.helpers import family_ip_tuple, log, Fatal
 from sshuttle.sudoers import sudoers
 from sshuttle.namespace import enter_namespace
 def main():
    if 'SSHUTTLE_ARGS' in os.environ:
        env_args = shlex.split(os.environ['SSHUTTLE_ARGS'])
    else:
        env_args = []
    args = [*env_args, *sys.argv[1:]]
    opt = parser.parse_args(args)
    if opt.sudoers_no_modify:
        # sudoers() calls exit() when it completes
        sudoers(user_name=opt.sudoers_user)
    if opt.daemon:
        opt.syslog = 1
    if opt.wrap:
        import sshuttle.ssnet as ssnet
        ssnet.MAX_CHANNEL = opt.wrap
    if opt.latency_buffer_size:
        import sshuttle.ssnet as ssnet
        ssnet.LATENCY_BUFFER_SIZE = opt.latency_buffer_size
    helpers.verbose = opt.verbose
    try:
        # Since namespace and namespace-pid options are only available
        # in linux, we must check if it exists with getattr
        namespace = getattr(opt, 'namespace', None)
        namespace_pid = getattr(opt, 'namespace_pid', None)
        if namespace or namespace_pid:
            prefix = helpers.logprefix
            helpers.logprefix = 'ns: '
            enter_namespace(namespace, namespace_pid)
            helpers.logprefix = prefix
        if opt.firewall:
            if opt.subnets or opt.subnets_file:
                parser.error('exactly zero arguments expected')
            return firewall.main(opt.method, opt.syslog)
        elif opt.hostwatch:
            hostwatch.hw_main(opt.subnets, opt.auto_hosts)
            return 0
        else:
            # parse_subnetports() is used to create a list of includes
            # and excludes. It is called once for each parameter and
            # returns a list of one or more items for each subnet (it
            # can return more than one item when a hostname in the
            # parameter resolves to multiple IP addresses. Here, we
            # flatten these lists.
            includes = [item for sublist in opt.subnets+opt.subnets_file
                        for item in sublist]
            excludes = [item for sublist in opt.exclude for item in sublist]
            if not includes and not opt.auto_nets:
                parser.error('at least one subnet, subnet file, '
                             'or -N expected')
            remotename = opt.remote
            if remotename == '' or remotename == '-':
                remotename = None
            nslist = [family_ip_tuple(ns) for ns in opt.ns_hosts]
            if opt.seed_hosts:
                sh = re.split(r'[\s,]+', (opt.seed_hosts or "").strip())
            elif opt.auto_hosts:
                sh = []
            else:
                sh = None
            if opt.listen:
                ipport_v6 = None
                ipport_v4 = None
                lst = opt.listen.split(",")
                for ip in lst:
                    family, ip, port = parse_ipport(ip)
                    if family == socket.AF_INET6:
                        ipport_v6 = (ip, port)
                    else:
                        ipport_v4 = (ip, port)
            else:
                # parse_ipport4('127.0.0.1:0')
                ipport_v4 = "auto"
                # parse_ipport6('[::1]:0')
                ipport_v6 = "auto" if not opt.disable_ipv6 else None
            try:
                int(opt.tmark, 16)
            except ValueError:
                parser.error("--tmark must be a hexadecimal value")
            opt.tmark = opt.tmark.lower()   # make 'x' in 0x lowercase
            if not opt.tmark.startswith("0x"):  # accept without 0x prefix
                opt.tmark = "0x%s" % opt.tmark
            if opt.syslog:
                ssyslog.start_syslog()
                ssyslog.close_stdin()
                ssyslog.stdout_to_syslog()
                ssyslog.stderr_to_syslog()
            return_code = client.main(ipport_v6, ipport_v4,
                                      opt.ssh_cmd,
                                      remotename,
                                      opt.python,
                                      opt.latency_control,
                                      opt.latency_buffer_size,
                                      opt.dns,
                                      nslist,
                                      opt.method,
                                      sh,
                                      opt.auto_hosts,
                                      opt.auto_nets,
                                      includes,
                                      excludes,
                                      opt.daemon,
                                      opt.to_ns,
                                      opt.pidfile,
                                      opt.user,
                                      opt.group,
                                      opt.sudo_pythonpath,
                                      opt.add_cmd_delimiter,
                                      opt.remote_shell,
                                      opt.tmark)
            if return_code == 0:
                log('Normal exit code, exiting...')
            else:
                log('Abnormal exit code %d detected, failing...' % return_code)
            return return_code
    except Fatal as e:
        log('fatal: %s' % e)
        return 99
    except KeyboardInterrupt:
        log('\n')
        log('Keyboard interrupt: exiting.')
        return 1
--- a/sshuttle/firewall.py
+++ b/sshuttle/firewall.py
@ -1,428 +0,0 @@
 import errno
 import shutil
 import socket
 import signal
 import sys
 import os
 import platform
 import traceback
 import subprocess as ssubprocess
 import base64
 import io
 import sshuttle.ssyslog as ssyslog
 import sshuttle.helpers as helpers
 from sshuttle.helpers import is_admin_user, log, debug1, debug2, debug3, Fatal
 from sshuttle.methods import get_auto_method, get_method
 if sys.platform == 'win32':
    HOSTSFILE = r"C:\Windows\System32\drivers\etc\hosts"
 else:
    HOSTSFILE = '/etc/hosts'
 sshuttle_pid = None
 def rewrite_etc_hosts(hostmap, port):
    BAKFILE = '%s.sbak' % HOSTSFILE
    APPEND = '# sshuttle-firewall-%d AUTOCREATED' % port
    old_content = ''
    st = None
    try:
        old_content = open(HOSTSFILE).read()
        st = os.stat(HOSTSFILE)
    except IOError as e:
        if e.errno == errno.ENOENT:
            pass
        else:
            raise
    if old_content.strip() and not os.path.exists(BAKFILE):
        try:
            os.link(HOSTSFILE, BAKFILE)
        except OSError:
            # file is locked - performing non-atomic copy
            shutil.copyfile(HOSTSFILE, BAKFILE)
    tmpname = "%s.%d.tmp" % (HOSTSFILE, port)
    f = open(tmpname, 'w')
    for line in old_content.rstrip().split('\n'):
        if line.find(APPEND) >= 0:
            continue
        f.write('%s\n' % line)
    for (name, ip) in sorted(hostmap.items()):
        f.write('%-30s %s\n' % ('%s %s' % (ip, name), APPEND))
    f.close()
    if sys.platform != 'win32':
        if st is not None:
            os.chown(tmpname, st.st_uid, st.st_gid)
            os.chmod(tmpname, st.st_mode)
        else:
            os.chown(tmpname, 0, 0)
            os.chmod(tmpname, 0o644)
    try:
        os.rename(tmpname, HOSTSFILE)
    except OSError:
        # file is locked - performing non-atomic copy
        log('Warning: Using a non-atomic way to overwrite %s that can corrupt the file if '
            'multiple processes write to it simultaneously.' % HOSTSFILE)
        shutil.move(tmpname, HOSTSFILE)
 def restore_etc_hosts(hostmap, port):
    # Only restore if we added hosts to /etc/hosts previously.
    if len(hostmap) > 0:
        debug2('undoing /etc/hosts changes.')
        rewrite_etc_hosts({}, port)
 def firewall_exit(signum, frame):
    # The typical sshuttle exit is that the main sshuttle process
    # exits, closes file descriptors it uses, and the firewall process
    # notices that it can't read from stdin anymore and exits
    # (cleaning up firewall rules).
    #
    # However, in some cases, Ctrl+C might get sent to the firewall
    # process. This might caused if someone manually tries to kill the
    # firewall process, or if sshuttle was started using sudo's use_pty option
    # and they try to exit by pressing Ctrl+C. Here, we forward the
    # Ctrl+C/SIGINT to the main sshuttle process which should trigger
    # the typical exit process as described above.
    global sshuttle_pid
    if sshuttle_pid:
        debug1("Relaying interupt signal to sshuttle process %d" % sshuttle_pid)
        if sys.platform == 'win32':
            sig = signal.CTRL_C_EVENT
        else:
            sig = signal.SIGINT
        os.kill(sshuttle_pid, sig)
 def _setup_daemon_for_unix_like():
    if not is_admin_user():
        raise Fatal('You must have root privileges (or enable su/sudo) to set the firewall')
    # don't disappear if our controlling terminal or stdout/stderr
    # disappears; we still have to clean up.
    signal.signal(signal.SIGHUP, signal.SIG_IGN)
    signal.signal(signal.SIGPIPE, signal.SIG_IGN)
    signal.signal(signal.SIGTERM, firewall_exit)
    signal.signal(signal.SIGINT, firewall_exit)
    # Calling setsid() here isn't strictly necessary. However, it forces
    # Ctrl+C to get sent to the main sshuttle process instead of to
    # the firewall process---which is our preferred way to shutdown.
    # Nonetheless, if the firewall process receives a SIGTERM/SIGINT
    # signal, it will relay a SIGINT to the main sshuttle process
    # automatically.
    try:
        os.setsid()
    except OSError:
        # setsid() fails if sudo is configured with the use_pty option.
        pass
    return sys.stdin.buffer, sys.stdout.buffer
 def _setup_daemon_for_windows():
    if not is_admin_user():
        raise Fatal('You must be administrator to set the firewall')
    signal.signal(signal.SIGTERM, firewall_exit)
    signal.signal(signal.SIGINT, firewall_exit)
    com_chan = os.environ.get('SSHUTTLE_FW_COM_CHANNEL')
    if com_chan == 'stdio':
        debug3('Using inherited stdio for communicating with sshuttle client process')
    else:
        debug3('Using shared socket for communicating with sshuttle client process')
        socket_share_data = base64.b64decode(com_chan)
        sock = socket.fromshare(socket_share_data)  # type: socket.socket
        sys.stdin = io.TextIOWrapper(sock.makefile('rb', buffering=0))
        sys.stdout = io.TextIOWrapper(sock.makefile('wb', buffering=0), write_through=True)
        sock.close()
    return sys.stdin.buffer, sys.stdout.buffer
 # Isolate function that needs to be replaced for tests
 if sys.platform == 'win32':
    setup_daemon = _setup_daemon_for_windows
 else:
    setup_daemon = _setup_daemon_for_unix_like
 # Note that we're sorting in a very particular order:
 # we need to go from smaller, more specific, port ranges, to larger,
 # less-specific, port ranges. At each level, we order by subnet
 # width, from most-specific subnets (largest swidth) to
 # least-specific. On ties, excludes come first.
 # s:(inet, subnet width, exclude flag, subnet, first port, last port)
 def subnet_weight(s):
    return (-s[-1] + (s[-2] or -65535), s[1], s[2])
 def flush_systemd_dns_cache():
    # If the user is using systemd-resolve for DNS resolution, it is
    # possible for the request to go through systemd-resolve before we
    # see it...and it may use a cached result instead of sending a
    # request that we can intercept. When sshuttle starts and stops,
    # this means that we should clear the cache!
    #
    # The command to do this was named systemd-resolve, but changed to
    # resolvectl in systemd 239.
    # https://github.com/systemd/systemd/blob/f8eb41003df1a4eab59ff9bec67b2787c9368dbd/NEWS#L3816
    p = None
    if helpers.which("resolvectl"):
        debug2("Flushing systemd's DNS resolver cache: "
               "resolvectl flush-caches")
        p = ssubprocess.Popen(["resolvectl", "flush-caches"],
                              stdout=ssubprocess.PIPE, env=helpers.get_env())
    elif helpers.which("systemd-resolve"):
        debug2("Flushing systemd's DNS resolver cache: "
               "systemd-resolve --flush-caches")
        p = ssubprocess.Popen(["systemd-resolve", "--flush-caches"],
                              stdout=ssubprocess.PIPE, env=helpers.get_env())
    if p:
        # Wait so flush is finished and process doesn't show up as defunct.
        rv = p.wait()
        if rv != 0:
            log("Received non-zero return code %d when flushing DNS resolver "
                "cache." % rv)
 # This is some voodoo for setting up the kernel's transparent
 # proxying stuff.  If subnets is empty, we just delete our sshuttle rules;
 # otherwise we delete it, then make them from scratch.
 #
 # This code is supposed to clean up after itself by deleting its rules on
 # exit.  In case that fails, it's not the end of the world; future runs will
 # supersede it in the transproxy list, at least, so the leftover rules
 # are hopefully harmless.
 def main(method_name, syslog):
    helpers.logprefix = 'fw: '
    stdin, stdout = setup_daemon()
    hostmap = {}
    debug1('Starting firewall with Python version %s'
           % platform.python_version())
    if method_name == "auto":
        method = get_auto_method()
    else:
        method = get_method(method_name)
    if syslog:
        ssyslog.start_syslog()
        ssyslog.stderr_to_syslog()
    if not method.is_supported():
        raise Fatal("The %s method is not supported on this machine. "
                    "Check that the appropriate programs are in your "
                    "PATH." % method_name)
    debug1('ready method name %s.' % method.name)
    stdout.write(('READY %s\n' % method.name).encode('ASCII'))
    stdout.flush()
    def _read_next_string_line():
        try:
            line = stdin.readline(128)
            if not line:
                return  # parent probably exited
            return line.decode('ASCII').strip()
        except IOError as e:
            # On windows, ConnectionResetError is thrown when parent process closes it's socket pair end
            debug3('read from stdin failed: %s' % (e,))
            return
    # we wait until we get some input before creating the rules.  That way,
    # sshuttle can launch us as early as possible (and get sudo password
    # authentication as early in the startup process as possible).
    try:
        line = _read_next_string_line()
        if not line:
            return  # parent probably exited
    except IOError as e:
        # On windows, ConnectionResetError is thrown when parent process closes it's socket pair end
        debug3('read from stdin failed: %s' % (e,))
        return
    subnets = []
    if line != 'ROUTES':
        raise Fatal('expected ROUTES but got %r' % line)
    while 1:
        line = _read_next_string_line()
        if not line:
            raise Fatal('expected route but got %r' % line)
        elif line.startswith("NSLIST"):
            break
        try:
            (family, width, exclude, ip, fport, lport) = line.split(',', 5)
        except Exception:
            raise Fatal('expected route or NSLIST but got %r' % line)
        subnets.append((
            int(family),
            int(width),
            bool(int(exclude)),
            ip,
            int(fport),
            int(lport)))
    debug2('Got subnets: %r' % subnets)
    nslist = []
    if line != 'NSLIST':
        raise Fatal('expected NSLIST but got %r' % line)
    while 1:
        line = _read_next_string_line()
        if not line:
            raise Fatal('expected nslist but got %r' % line)
        elif line.startswith("PORTS "):
            break
        try:
            (family, ip) = line.split(',', 1)
        except Exception:
            raise Fatal('expected nslist or PORTS but got %r' % line)
        nslist.append((int(family), ip))
        debug2('Got partial nslist: %r' % nslist)
    debug2('Got nslist: %r' % nslist)
    if not line.startswith('PORTS '):
        raise Fatal('expected PORTS but got %r' % line)
    _, _, ports = line.partition(" ")
    ports = ports.split(",")
    if len(ports) != 4:
        raise Fatal('expected 4 ports but got %d' % len(ports))
    port_v6 = int(ports[0])
    port_v4 = int(ports[1])
    dnsport_v6 = int(ports[2])
    dnsport_v4 = int(ports[3])
    assert port_v6 >= 0
    assert port_v6 <= 65535
    assert port_v4 >= 0
    assert port_v4 <= 65535
    assert dnsport_v6 >= 0
    assert dnsport_v6 <= 65535
    assert dnsport_v4 >= 0
    assert dnsport_v4 <= 65535
    debug2('Got ports: %d,%d,%d,%d'
           % (port_v6, port_v4, dnsport_v6, dnsport_v4))
    line = _read_next_string_line()
    if not line or not line.startswith("GO "):
        raise Fatal('expected GO but got %r' % line)
    _, _, args = line.partition(" ")
    global sshuttle_pid
    udp, user, group, tmark, sshuttle_pid = args.split(" ", 4)
    udp = bool(int(udp))
    sshuttle_pid = int(sshuttle_pid)
    if user == '-':
        user = None
    if group == '-':
        group = None
    debug2('Got udp: %r, user: %r, group: %r, tmark: %s, sshuttle_pid: %d' %
           (udp, user, group, tmark, sshuttle_pid))
    subnets_v6 = [i for i in subnets if i[0] == socket.AF_INET6]
    nslist_v6 = [i for i in nslist if i[0] == socket.AF_INET6]
    subnets_v4 = [i for i in subnets if i[0] == socket.AF_INET]
    nslist_v4 = [i for i in nslist if i[0] == socket.AF_INET]
    try:
        debug1('setting up.')
        if subnets_v6 or nslist_v6:
            debug2('setting up IPv6.')
            method.setup_firewall(
                port_v6, dnsport_v6, nslist_v6,
                socket.AF_INET6, subnets_v6, udp,
                user, group, tmark)
        if subnets_v4 or nslist_v4:
            debug2('setting up IPv4.')
            method.setup_firewall(
                port_v4, dnsport_v4, nslist_v4,
                socket.AF_INET, subnets_v4, udp,
                user, group, tmark)
        try:
            # For some methods (eg: windivert) firewall setup will be differed / will run asynchronously.
            # Such method implements wait_for_firewall_ready() to wait until firewall is up and running.
            method.wait_for_firewall_ready(sshuttle_pid)
        except NotImplementedError:
            pass
        if sys.platform == 'linux':
            flush_systemd_dns_cache()
        try:
            stdout.write(b'STARTED\n')
            stdout.flush()
        except IOError as e:  # the parent process probably died
            debug3('write to stdout failed: %s' % (e,))
            return
        # Now we wait until EOF or any other kind of exception.  We need
        # to stay running so that we don't need a *second* password
        # authentication at shutdown time - that cleanup is important!
        while 1:
            line = _read_next_string_line()
            if not line:
                return
            if line.startswith('HOST '):
                (name, ip) = line[5:].split(',', 1)
                hostmap[name] = ip
                debug2('setting up /etc/hosts.')
                rewrite_etc_hosts(hostmap, port_v6 or port_v4)
            elif line:
                if not method.firewall_command(line):
                    raise Fatal('expected command, got %r' % line)
            else:
                break
    finally:
        try:
            debug1('undoing changes.')
        except Exception:
            debug2('An error occurred, ignoring it.')
        try:
            if subnets_v6 or nslist_v6:
                debug2('undoing IPv6 changes.')
                method.restore_firewall(port_v6, socket.AF_INET6, udp, user, group)
        except Exception:
            try:
                debug1("Error trying to undo IPv6 firewall.")
                debug1(traceback.format_exc())
            except Exception:
                debug2('An error occurred, ignoring it.')
        try:
            if subnets_v4 or nslist_v4:
                debug2('undoing IPv4 changes.')
                method.restore_firewall(port_v4, socket.AF_INET, udp, user, group)
        except Exception:
            try:
                debug1("Error trying to undo IPv4 firewall.")
                debug1(traceback.format_exc())
            except Exception:
                debug2('An error occurred, ignoring it.')
        try:
            # debug2() message printed in restore_etc_hosts() function.
            restore_etc_hosts(hostmap, port_v6 or port_v4)
        except Exception:
            try:
                debug1("Error trying to undo /etc/hosts changes.")
                debug1(traceback.format_exc())
            except Exception:
                debug2('An error occurred, ignoring it.')
        if sys.platform == 'linux':
            try:
                flush_systemd_dns_cache()
            except Exception:
                try:
                    debug1("Error trying to flush systemd dns cache.")
                    debug1(traceback.format_exc())
                except Exception:
                    debug2("An error occurred, ignoring it.")
--- a/sshuttle/helpers.py
+++ b/sshuttle/helpers.py
@ -1,349 +0,0 @@
 import sys
 import socket
 import errno
 import os
 import threading
 import subprocess
 import traceback
 import re
 if sys.platform != "win32":
    import fcntl
 logprefix = ''
 verbose = 0
 def b(s):
    return s.encode("ASCII")
 def get_verbose_level():
    return verbose
 def log(s):
    global logprefix
    try:
        sys.stdout.flush()
    except (IOError, ValueError):  # ValueError ~ I/O operation on closed file
        pass
    try:
        # Put newline at end of string if line doesn't have one.
        if not s.endswith("\n"):
            s = s+"\n"
        prefix = logprefix
        s = s.rstrip("\n")
        for line in s.split("\n"):
            sys.stderr.write(prefix + line + "\n")
            prefix = "    "
        sys.stderr.flush()
    except (IOError, ValueError):  # ValueError ~ I/O operation on closed file
        # this could happen if stderr gets forcibly disconnected, eg. because
        # our tty closes.  That sucks, but it's no reason to abort the program.
        pass
 def debug1(s):
    if verbose >= 1:
        log(s)
 def debug2(s):
    if verbose >= 2:
        log(s)
 def debug3(s):
    if verbose >= 3:
        log(s)
 class Fatal(Exception):
    pass
 def resolvconf_nameservers(systemd_resolved):
    """Retrieves a list of tuples (address type, address as a string) of
    the DNS servers used by the system to resolve hostnames.
    If parameter is False, DNS servers are retrieved from only
    /etc/resolv.conf. This behavior makes sense for the sshuttle
    server.
    If parameter is True, we retrieve information from both
    /etc/resolv.conf and /run/systemd/resolve/resolv.conf (if it
    exists). This behavior makes sense for the sshuttle client.
    """
    # Historically, we just needed to read /etc/resolv.conf.
    #
    # If systemd-resolved is active, /etc/resolv.conf will point to
    # localhost and the actual DNS servers that systemd-resolved uses
    # are stored in /run/systemd/resolve/resolv.conf. For programs
    # that use the localhost DNS server, having sshuttle read
    # /etc/resolv.conf is sufficient. However, resolved provides other
    # ways of resolving hostnames (such as via dbus) that may not
    # route requests through localhost. So, we retrieve a list of DNS
    # servers that resolved uses so we can intercept those as well.
    #
    # For more information about systemd-resolved, see:
    # https://www.freedesktop.org/software/systemd/man/systemd-resolved.service.html
    #
    # On machines without systemd-resolved, we expect opening the
    # second file will fail.
    files = ['/etc/resolv.conf']
    if systemd_resolved:
        files += ['/run/systemd/resolve/resolv.conf']
    nsservers = []
    for f in files:
        this_file_nsservers = []
        try:
            for line in open(f):
                words = line.lower().split()
                if len(words) >= 2 and words[0] == 'nameserver':
                    this_file_nsservers.append(family_ip_tuple(words[1]))
            debug2("Found DNS servers in %s: %s" %
                   (f, [n[1] for n in this_file_nsservers]))
            nsservers += this_file_nsservers
        except OSError as e:
            debug3("Failed to read %s when looking for DNS servers: %s" %
                   (f, e.strerror))
    return nsservers
 def windows_nameservers():
    out = subprocess.check_output(["powershell", "-NonInteractive", "-NoProfile", "-Command", "Get-DnsClientServerAddress"],
                                  encoding="utf-8")
    servers = set()
    for line in out.splitlines():
        if line.startswith("Loopback "):
            continue
        m = re.search(r'{.+}', line)
        if not m:
            continue
        for s in m.group().strip('{}').split(','):
            s = s.strip()
            if s.startswith('fec0:0:0:ffff'):
                continue
            servers.add(s)
    debug2("Found DNS servers: %s" % servers)
    return [(socket.AF_INET6 if ':' in s else socket.AF_INET, s) for s in servers]
 def get_random_nameserver():
    """Return a random nameserver selected from servers produced by
    resolvconf_nameservers()/windows_nameservers()
    """
    if sys.platform == "win32":
        if globals().get('_nameservers') is None:
            ns_list = windows_nameservers()
            globals()['_nameservers'] = ns_list
        else:
            ns_list = globals()['_nameservers']
    else:
        ns_list = resolvconf_nameservers(systemd_resolved=False)
    if ns_list:
        if len(ns_list) > 1:
            # don't import this unless we really need it
            import random
            random.shuffle(ns_list)
        return ns_list[0]
    else:
        return (socket.AF_INET, '127.0.0.1')
 def islocal(ip, family):
    sock = socket.socket(family)
    try:
        try:
            sock.bind((ip, 0))
        except socket.error:
            _, e = sys.exc_info()[:2]
            if e.args[0] == errno.EADDRNOTAVAIL:
                return False  # not a local IP
            else:
                raise
    finally:
        sock.close()
    return True  # it's a local IP, or there would have been an error
 def family_ip_tuple(ip):
    if ':' in ip:
        return (socket.AF_INET6, ip)
    else:
        return (socket.AF_INET, ip)
 def family_to_string(family):
    if family == socket.AF_INET6:
        return "AF_INET6"
    elif family == socket.AF_INET:
        return "AF_INET"
    else:
        return str(family)
 def get_env():
    """An environment for sshuttle subprocesses. See get_path()."""
    env = {
        'PATH': get_path(),
        'LC_ALL': "C",
    }
    return env
 def get_path():
    """Returns a string of paths separated by os.pathsep.
    Users might not have all of the programs sshuttle needs in their
    PATH variable (i.e., some programs might be in /sbin). Use PATH
    and a hardcoded set of paths to search through. This function is
    used by our which() and get_env() functions. If which() and the
    subprocess environments differ, programs that which() finds might
    not be found at run time (or vice versa).
    """
    path = []
    if "PATH" in os.environ:
        path += os.environ["PATH"].split(os.pathsep)
    # Python default paths.
    path += os.defpath.split(os.pathsep)
    # /sbin, etc are not in os.defpath and may not be in PATH either.
    # /bin/ and /usr/bin below are probably redundant.
    path += ['/bin', '/usr/bin', '/sbin', '/usr/sbin']
    # Remove duplicates. Not strictly necessary.
    path_dedup = []
    for i in path:
        if i not in path_dedup:
            path_dedup.append(i)
    return os.pathsep.join(path_dedup)
 if sys.version_info >= (3, 3):
    from shutil import which as _which
 else:
    # Although sshuttle does not officially support older versions of
    # Python, some still run the sshuttle server on remote machines
    # with old versions of python.
    def _which(file, mode=os.F_OK | os.X_OK, path=None):
        if path is not None:
            search_paths = path.split(os.pathsep)
        elif "PATH" in os.environ:
            search_paths = os.environ["PATH"].split(os.pathsep)
        else:
            search_paths = os.defpath.split(os.pathsep)
        for p in search_paths:
            filepath = os.path.join(p, file)
            if os.path.exists(filepath) and os.access(filepath, mode):
                return filepath
        return None
 def which(file, mode=os.F_OK | os.X_OK):
    """A wrapper around shutil.which() that searches a predictable set of
    paths and is more verbose about what is happening. See get_path()
    for more information.
    """
    path = get_path()
    rv = _which(file, mode, path)
    if rv:
        debug2("which() found '%s' at %s" % (file, rv))
    else:
        debug2("which() could not find '%s' in %s" % (file, path))
    return rv
 def is_admin_user():
    if sys.platform == 'win32':
        # https://stackoverflow.com/questions/130763/request-uac-elevation-from-within-a-python-script/41930586#41930586
        import ctypes
        try:
            return ctypes.windll.shell32.IsUserAnAdmin()
        except Exception:
            return False
    # TODO(nom3ad): for sys.platform == 'linux', check capabilities for non-root users. (CAP_NET_ADMIN might be enough?)
    return os.getuid() == 0
 def set_non_blocking_io(fd):
    if sys.platform != "win32":
        try:
            os.set_blocking(fd, False)
        except AttributeError:
            # python < 3.5
            flags = fcntl.fcntl(fd, fcntl.F_GETFL)
            flags |= os.O_NONBLOCK
            fcntl.fcntl(fd, fcntl.F_SETFL, flags)
    else:
        _sock = socket.fromfd(fd, socket.AF_INET, socket.SOCK_STREAM)
        _sock.setblocking(False)
 class RWPair:
    def __init__(self, r, w):
        self.r = r
        self.w = w
        self.read = r.read
        self.readline = r.readline
        self.write = w.write
        self.flush = w.flush
    def close(self):
        for f in self.r, self.w:
            try:
                f.close()
            except Exception:
                pass
 class SocketRWShim:
    __slots__ = ('_r', '_w', '_on_end', '_s1', '_s2', '_t1', '_t2')
    def __init__(self, r, w, on_end=None):
        self._r = r
        self._w = w
        self._on_end = on_end
        self._s1, self._s2 = socket.socketpair()
        debug3("[SocketShim] r=%r w=%r | s1=%r s2=%r" % (self._r, self._w, self._s1, self._s2))
        def stream_reader_to_sock():
            try:
                for data in iter(lambda:  self._r.read(16384), b''):
                    self._s1.sendall(data)
                    # debug3("[SocketRWShim] <<<<< r.read() %d %r..." % (len(data), data[:min(32, len(data))]))
            except Exception:
                traceback.print_exc(file=sys.stderr)
            finally:
                debug2("[SocketRWShim] Thread 'stream_reader_to_sock' exiting")
                self._s1.close()
                self._on_end and self._on_end()
        def stream_sock_to_writer():
            try:
                for data in iter(lambda: self._s1.recv(16384), b''):
                    while data:
                        n = self._w.write(data)
                        data = data[n:]
                    # debug3("[SocketRWShim] <<<<< w.write() %d %r..." % (len(data), data[:min(32, len(data))]))
            except Exception:
                traceback.print_exc(file=sys.stderr)
            finally:
                debug2("[SocketRWShim] Thread 'stream_sock_to_writer' exiting")
                self._s1.close()
                self._on_end and self._on_end()
        self._t1 = threading.Thread(target=stream_reader_to_sock,  name='stream_reader_to_sock', daemon=True).start()
        self._t2 = threading.Thread(target=stream_sock_to_writer, name='stream_sock_to_writer',  daemon=True).start()
    def makefiles(self):
        return self._s2.makefile("rb", buffering=0), self._s2.makefile("wb", buffering=0)
--- a/sshuttle/hostwatch.py
+++ b/sshuttle/hostwatch.py
@ -1,250 +0,0 @@
 import time
 import socket
 import re
 import select
 import errno
 import os
 import sys
 import platform
 import subprocess as ssubprocess
 import sshuttle.helpers as helpers
 from sshuttle.helpers import log, debug1, debug2, debug3, get_env
 POLL_TIME = 60 * 15
 NETSTAT_POLL_TIME = 30
 CACHEFILE = os.path.expanduser('~/.sshuttle.hosts')
 # Have we already failed to write CACHEFILE?
 CACHE_WRITE_FAILED = False
 SHOULD_WRITE_CACHE = False
 hostnames = {}
 queue = {}
 try:
    null = open(os.devnull, 'wb')
 except IOError:
    _, e = sys.exc_info()[:2]
    log('warning: %s' % e)
    null = os.popen("sh -c 'while read x; do :; done'", 'wb', 4096)
 def _is_ip(s):
    return re.match(r'\d+\.\d+\.\d+\.\d+$', s)
 def write_host_cache():
    """If possible, write our hosts file to disk so future connections
       can reuse the hosts that we already found."""
    tmpname = '%s.%d.tmp' % (CACHEFILE, os.getpid())
    global CACHE_WRITE_FAILED
    try:
        f = open(tmpname, 'wb')
        for name, ip in sorted(hostnames.items()):
            f.write(('%s,%s\n' % (name, ip)).encode("ASCII"))
        f.close()
        os.chmod(tmpname, 384)  # 600 in octal, 'rw-------'
        os.rename(tmpname, CACHEFILE)
        CACHE_WRITE_FAILED = False
    except (OSError, IOError):
        # Write message if we haven't yet or if we get a failure after
        # a previous success.
        if not CACHE_WRITE_FAILED:
            log("Failed to write host cache to temporary file "
                "%s and rename it to %s" % (tmpname, CACHEFILE))
            CACHE_WRITE_FAILED = True
        try:
            os.unlink(tmpname)
        except Exception:
            pass
 def read_host_cache():
    """If possible, read the cache file from disk to populate hosts that
       were found in a previous sshuttle run."""
    try:
        f = open(CACHEFILE)
    except (OSError, IOError):
        _, e = sys.exc_info()[:2]
        if e.errno == errno.ENOENT:
            return
        else:
            log("Failed to read existing host cache file %s on remote host"
                % CACHEFILE)
            return
    for line in f:
        words = line.strip().split(',')
        if len(words) == 2:
            (name, ip) = words
            name = re.sub(r'[^-\w\.]', '-', name).strip()
            # Remove characters that shouldn't be in IP
            ip = re.sub(r'[^0-9.]', '', ip).strip()
            if name and ip:
                found_host(name, ip)
    f.close()
    global SHOULD_WRITE_CACHE
    if SHOULD_WRITE_CACHE:
        write_host_cache()
        SHOULD_WRITE_CACHE = False
 def found_host(name, ip):
    """The provided name maps to the given IP. Add the host to the
       hostnames list, send the host to the sshuttle client via
       stdout, and write the host to the cache file.
    """
    hostname = re.sub(r'\..*', '', name)
    hostname = re.sub(r'[^-\w\.]', '_', hostname)
    if (ip.startswith('127.') or ip.startswith('255.') or
            hostname == 'localhost'):
        return
    if hostname != name:
        found_host(hostname, ip)
    global SHOULD_WRITE_CACHE
    oldip = hostnames.get(name)
    if oldip != ip:
        hostnames[name] = ip
        debug1('Found: %s: %s' % (name, ip))
        sys.stdout.write('%s,%s\n' % (name, ip))
        SHOULD_WRITE_CACHE = True
 def _check_etc_hosts():
    """If possible, read /etc/hosts to find hosts."""
    filename = '/etc/hosts'
    debug2(' > Reading %s on remote host' % filename)
    try:
        for line in open(filename):
            line = re.sub(r'#.*', '', line)  # remove comments
            words = line.strip().split()
            if not words:
                continue
            ip = words[0]
            if _is_ip(ip):
                names = words[1:]
                debug3('<    %s %r' % (ip, names))
                for n in names:
                    check_host(n)
                    found_host(n, ip)
    except (OSError, IOError):
        debug1("Failed to read %s on remote host" % filename)
 def _check_revdns(ip):
    """Use reverse DNS to try to get hostnames from an IP addresses."""
    debug2(' > rev: %s' % ip)
    try:
        r = socket.gethostbyaddr(ip)
        debug3('<    %s' % r[0])
        check_host(r[0])
        found_host(r[0], ip)
    except (OSError, socket.error, UnicodeError):
        # This case is expected to occur regularly.
        # debug3('<    %s gethostbyaddr failed on remote host' % ip)
        pass
 def _check_dns(hostname):
    debug2(' > dns: %s' % hostname)
    try:
        ip = socket.gethostbyname(hostname)
        debug3('<    %s' % ip)
        check_host(ip)
        found_host(hostname, ip)
    except (socket.gaierror, UnicodeError):
        pass
 def _check_netstat():
    debug2(' > netstat')
    argv = ['netstat', '-n']
    try:
        p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, stderr=null,
                              env=get_env())
        content = p.stdout.read().decode("ASCII")
        p.wait()
    except OSError:
        _, e = sys.exc_info()[:2]
        log('%r failed: %r' % (argv, e))
        return
    # The same IPs may appear multiple times. Consolidate them so the
    # debug message doesn't print the same IP repeatedly.
    ip_list = []
    for ip in re.findall(r'\d+\.\d+\.\d+\.\d+', content):
        if ip not in ip_list:
            ip_list.append(ip)
    for ip in sorted(ip_list):
        debug3('<    %s' % ip)
        check_host(ip)
 def check_host(hostname):
    if _is_ip(hostname):
        _enqueue(_check_revdns, hostname)
    else:
        _enqueue(_check_dns, hostname)
 def _enqueue(op, *args):
    t = (op, args)
    if queue.get(t) is None:
        queue[t] = 0
 def _stdin_still_ok(timeout):
    r, _, _ = select.select([sys.stdin.fileno()], [], [], timeout)
    if r:
        b = os.read(sys.stdin.fileno(), 4096)
        if not b:
            return False
    return True
 def hw_main(seed_hosts, auto_hosts):
    helpers.logprefix = 'HH: '
    debug1('Starting hostwatch with Python version %s'
           % platform.python_version())
    for h in seed_hosts:
        check_host(h)
    if auto_hosts:
        read_host_cache()
        _enqueue(_check_etc_hosts)
        _enqueue(_check_netstat)
        check_host('localhost')
        check_host(socket.gethostname())
    while 1:
        now = time.time()
        # For each item in the queue
        for t, last_polled in list(queue.items()):
            (op, args) = t
            if not _stdin_still_ok(0):
                break
            # Determine if we need to run.
            maxtime = POLL_TIME
            # netstat runs more often than other jobs
            if op == _check_netstat:
                maxtime = NETSTAT_POLL_TIME
            # Check if this jobs needs to run.
            if now - last_polled > maxtime:
                queue[t] = time.time()
                op(*args)
            try:
                sys.stdout.flush()
            except IOError:
                break
        # FIXME: use a smarter timeout based on oldest last_polled
        if not _stdin_still_ok(1):  # sleeps for up to 1 second
            break
--- a/sshuttle/linux.py
+++ b/sshuttle/linux.py
@ -1,51 +0,0 @@
 import socket
 import subprocess as ssubprocess
 from sshuttle.helpers import log, debug1, Fatal, family_to_string, get_env
 def nonfatal(func, *args):
    try:
        func(*args)
    except Fatal as e:
        log('error: %s' % e)
 def ipt_chain_exists(family, table, name):
    if family == socket.AF_INET6:
        cmd = 'ip6tables'
    elif family == socket.AF_INET:
        cmd = 'iptables'
    else:
        raise Exception('Unsupported family "%s"' % family_to_string(family))
    argv = [cmd, '-w', '-t', table, '-nL']
    try:
        output = ssubprocess.check_output(argv, env=get_env())
        for line in output.decode('ASCII', errors='replace').split('\n'):
            if line.startswith('Chain %s ' % name):
                return True
    except ssubprocess.CalledProcessError as e:
        raise Fatal('%r returned %d' % (argv, e.returncode))
 def ipt(family, table, *args):
    if family == socket.AF_INET6:
        argv = ['ip6tables', '-w', '-t', table] + list(args)
    elif family == socket.AF_INET:
        argv = ['iptables', '-w', '-t', table] + list(args)
    else:
        raise Exception('Unsupported family "%s"' % family_to_string(family))
    debug1('%s' % ' '.join(argv))
    rv = ssubprocess.call(argv, env=get_env())
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
 def nft(family, table, action, *args):
    if family in (socket.AF_INET, socket.AF_INET6):
        argv = ['nft', action, 'inet', table] + list(args)
    else:
        raise Exception('Unsupported family "%s"' % family_to_string(family))
    debug1('%s' % ' '.join(argv))
    rv = ssubprocess.call(argv, env=get_env())
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
--- a/sshuttle/methods/init.py
+++ b/sshuttle/methods/init.py
@ -1,126 +0,0 @@
 import importlib
 import socket
 import struct
 import sys
 import errno
 import ipaddress
 from sshuttle.helpers import Fatal, debug3
 def original_dst(sock):
    try:
        family = sock.family
        SO_ORIGINAL_DST = 80
        if family == socket.AF_INET:
            SOCKADDR_MIN = 16
            sockaddr_in = sock.getsockopt(socket.SOL_IP,
                                          SO_ORIGINAL_DST, SOCKADDR_MIN)
            port, raw_ip = struct.unpack_from('!2xH4s', sockaddr_in[:8])
            ip = str(ipaddress.IPv4Address(raw_ip))
        elif family == socket.AF_INET6:
            sockaddr_in = sock.getsockopt(41, SO_ORIGINAL_DST, 64)
            port, raw_ip = struct.unpack_from("!2xH4x16s", sockaddr_in)
            ip = str(ipaddress.IPv6Address(raw_ip))
        else:
            raise Fatal("fw: Unknown family type.")
    except socket.error as e:
        if e.args[0] == errno.ENOPROTOOPT:
            return sock.getsockname()
        raise
    return (ip, port)
 class Features(object):
    pass
 class BaseMethod(object):
    def __init__(self, name):
        self.firewall = None
        self.name = name
    def set_firewall(self, firewall):
        self.firewall = firewall
    @staticmethod
    def get_supported_features():
        result = Features()
        result.loopback_proxy_port = True
        result.ipv4 = True
        result.ipv6 = False
        result.udp = False
        result.dns = True
        result.user = False
        result.group = False
        return result
    @staticmethod
    def is_supported():
        """Returns true if it appears that this method will work on this
        machine."""
        return False
    @staticmethod
    def get_tcp_dstip(sock):
        return original_dst(sock)
    @staticmethod
    def recv_udp(udp_listener, bufsize):
        debug3('Accept UDP using recvfrom.')
        data, srcip = udp_listener.recvfrom(bufsize)
        return (srcip, None, data)
    def send_udp(self, sock, srcip, dstip, data):
        if srcip is not None:
            raise Fatal("Method %s send_udp does not support setting srcip to %r"
                        % (self.name, srcip))
        sock.sendto(data, dstip)
    def setup_tcp_listener(self, tcp_listener):
        pass
    def setup_udp_listener(self, udp_listener):
        pass
    def assert_features(self, features):
        avail = self.get_supported_features()
        for key in ["udp", "dns", "ipv6", "ipv4", "user"]:
            if getattr(features, key) and not getattr(avail, key):
                raise Fatal(
                    "Feature %s not supported with method %s." %
                    (key, self.name))
    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
                       user, group, tmark):
        raise NotImplementedError()
    def restore_firewall(self, port, family, udp, user, group):
        raise NotImplementedError()
    def wait_for_firewall_ready(self, sshuttle_pid):
        raise NotImplementedError()
    @staticmethod
    def firewall_command(line):
        return False
 def get_method(method_name):
    module = importlib.import_module("sshuttle.methods.%s" % method_name)
    return module.Method(method_name)
 def get_auto_method():
    debug3("Selecting a method automatically...")
    # Try these methods, in order:
    methods_to_try = ["nat", "nft", "pf", "ipfw"] if sys.platform != "win32" else ["windivert"]
    for m in methods_to_try:
        method = get_method(m)
        if method.is_supported():
            debug3("Method '%s' was automatically selected." % m)
            return method
    raise Fatal("Unable to automatically find a supported method. Check that "
                "the appropriate programs are in your PATH. We tried "
                "methods: %s" % str(methods_to_try))
--- a/sshuttle/methods/ipfw.py
+++ b/sshuttle/methods/ipfw.py
@ -1,226 +0,0 @@
 import os
 import subprocess as ssubprocess
 from sshuttle.methods import BaseMethod
 from sshuttle.helpers import log, debug1, debug2, debug3, \
    Fatal, family_to_string, get_env, which
 import socket
 IP_BINDANY = 24
 IP_RECVDSTADDR = 7
 SOL_IPV6 = 41
 IPV6_RECVDSTADDR = 74
 def recv_udp(listener, bufsize):
    debug3('Accept UDP python using recvmsg.')
    data, ancdata, _, srcip = listener.recvmsg(4096,
                                               socket.CMSG_SPACE(4))
    dstip = None
    for cmsg_level, cmsg_type, cmsg_data in ancdata:
        if cmsg_level == socket.SOL_IP and cmsg_type == IP_RECVDSTADDR:
            port = 53
            ip = socket.inet_ntop(socket.AF_INET, cmsg_data[0:4])
            dstip = (ip, port)
            break
    return (srcip, dstip, data)
 def ipfw_rule_exists(n):
    argv = ['ipfw', 'list', '%d' % n]
    p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, env=get_env())
    found = False
    for line in p.stdout:
        if line.startswith(b'%05d ' % n):
            if 'check-state :sshuttle' not in line:
                log('non-sshuttle ipfw rule: %r' % line.strip())
                raise Fatal('non-sshuttle ipfw rule #%d already exists!' % n)
            found = True
            break
    rv = p.wait()
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
    return found
 _oldctls = {}
 def _fill_oldctls(prefix):
    argv = ['sysctl', prefix]
    p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, env=get_env())
    for line in p.stdout:
        line = line.decode()
        assert line[-1] == '\n'
        (k, v) = line[:-1].split(': ', 1)
        _oldctls[k] = v.strip()
    rv = p.wait()
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
    if not line:
        raise Fatal('%r returned no data' % (argv,))
 def _sysctl_set(name, val):
    argv = ['sysctl', '-w', '%s=%s' % (name, val)]
    debug1('>> %s' % ' '.join(argv))
    return ssubprocess.call(argv, stdout=open(os.devnull, 'w'), env=get_env())
    # No env: No output. (Or error that won't be parsed.)
 _changedctls = []
 def sysctl_set(name, val, permanent=False):
    PREFIX = 'net.inet.ip'
    assert name.startswith(PREFIX + '.')
    val = str(val)
    if not _oldctls:
        _fill_oldctls(PREFIX)
    if not (name in _oldctls):
        debug1('>> No such sysctl: %r' % name)
        return False
    oldval = _oldctls[name]
    if val != oldval:
        rv = _sysctl_set(name, val)
        if rv == 0 and permanent:
            debug1('>>   ...saving permanently in /etc/sysctl.conf')
            f = open('/etc/sysctl.conf', 'a')
            f.write('\n'
                    '# Added by sshuttle\n'
                    '%s=%s\n' % (name, val))
            f.close()
        else:
            _changedctls.append(name)
        return True
 def ipfw(*args):
    argv = ['ipfw', '-q'] + list(args)
    debug1('>> %s' % ' '.join(argv))
    rv = ssubprocess.call(argv, env=get_env())
    # No env: No output. (Or error that won't be parsed.)
    if rv:
        raise Fatal('%r returned %d' % (argv, rv))
 def ipfw_noexit(*args):
    argv = ['ipfw', '-q'] + list(args)
    debug1('>> %s' % ' '.join(argv))
    ssubprocess.call(argv, env=get_env())
    # No env: No output. (Or error that won't be parsed.)
 class Method(BaseMethod):
    def get_supported_features(self):
        result = super(Method, self).get_supported_features()
        result.ipv6 = False
        result.udp = False  # NOTE: Almost there, kernel patch needed
        result.dns = True
        return result
    def get_tcp_dstip(self, sock):
        return sock.getsockname()
    def recv_udp(self, udp_listener, bufsize):
        srcip, dstip, data = recv_udp(udp_listener, bufsize)
        if not dstip:
            debug1(
                   "-- ignored UDP from %r: "
                   "couldn't determine destination IP address" % (srcip,))
            return None
        return srcip, dstip, data
    def send_udp(self, sock, srcip, dstip, data):
        if not srcip:
            debug1(
               "-- ignored UDP to %r: "
               "couldn't determine source IP address" % (dstip,))
            return
        # debug3('Sending SRC: %r DST: %r' % (srcip, dstip))
        sender = socket.socket(sock.family, socket.SOCK_DGRAM)
        sender.setsockopt(socket.SOL_IP, IP_BINDANY, 1)
        sender.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        sender.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
        sender.bind(srcip)
        sender.sendto(data, dstip)
        sender.close()
    def setup_udp_listener(self, udp_listener):
        if udp_listener.v4 is not None:
            udp_listener.v4.setsockopt(socket.SOL_IP, IP_RECVDSTADDR, 1)
        # if udp_listener.v6 is not None:
        #     udp_listener.v6.setsockopt(SOL_IPV6, IPV6_RECVDSTADDR, 1)
    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
                       user, group, tmark):
        # IPv6 not supported
        if family not in [socket.AF_INET]:
            raise Exception(
                'Address family "%s" unsupported by ipfw method_name'
                % family_to_string(family))
        # XXX: Any risk from this?
        ipfw_noexit('delete', '1')
        while _changedctls:
            name = _changedctls.pop()
            oldval = _oldctls[name]
            _sysctl_set(name, oldval)
        if subnets or dnsport:
            sysctl_set('net.inet.ip.fw.enable', 1)
        ipfw('add', '1', 'check-state', ':sshuttle')
        ipfw('add', '1', 'skipto', '2',
             'tcp',
             'from', 'any', 'to', 'table(125)')
        ipfw('add', '1', 'fwd', '127.0.0.1,%d' % port,
             'tcp',
             'from', 'any', 'to', 'table(126)',
             'setup', 'keep-state', ':sshuttle')
        ipfw_noexit('table', '124', 'flush')
        dnscount = 0
        for _, ip in [i for i in nslist if i[0] == family]:
            ipfw('table', '124', 'add', '%s' % (ip))
            dnscount += 1
        if dnscount > 0:
            ipfw('add', '1', 'fwd', '127.0.0.1,%d' % dnsport,
                 'udp',
                 'from', 'any', 'to', 'table(124)',
                 'keep-state', ':sshuttle')
        ipfw('add', '1', 'allow',
             'udp',
             'from', 'any', 'to', 'any')
        if subnets:
            # create new subnet entries
            for _, swidth, sexclude, snet, fport, lport \
                    in sorted(subnets, key=lambda s: s[1], reverse=True):
                if sexclude:
                    ipfw('table', '125', 'add', '%s/%s' % (snet, swidth))
                else:
                    ipfw('table', '126', 'add', '%s/%s' % (snet, swidth))
    def restore_firewall(self, port, family, udp, user, group):
        if family not in [socket.AF_INET]:
            raise Exception(
                'Address family "%s" unsupported by ipfw method'
                % family_to_string(family))
        ipfw_noexit('delete', '1')
        ipfw_noexit('table', '124', 'flush')
        ipfw_noexit('table', '125', 'flush')
        ipfw_noexit('table', '126', 'flush')
    def is_supported(self):
        if which("ipfw"):
            return True
        debug2("ipfw method not supported because 'ipfw' command is "
               "missing.")
        return False
--- a/sshuttle/methods/nat.py
+++ b/sshuttle/methods/nat.py
@ -1,133 +0,0 @@
 import socket
 from sshuttle.firewall import subnet_weight
 from sshuttle.helpers import family_to_string, which, debug2
 from sshuttle.linux import ipt, ipt_chain_exists, nonfatal
 from sshuttle.methods import BaseMethod
 class Method(BaseMethod):
    # We name the chain based on the transproxy port number so that it's
    # possible to run multiple copies of sshuttle at the same time.  Of course,
    # the multiple copies shouldn't have overlapping subnets, or only the most-
    # recently-started one will win (because we use "-I OUTPUT 1" instead of
    # "-A OUTPUT").
    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
                       user, group, tmark):
        if family != socket.AF_INET and family != socket.AF_INET6:
            raise Exception(
                'Address family "%s" unsupported by nat method_name'
                % family_to_string(family))
        if udp:
            raise Exception("UDP not supported by nat method_name")
        table = "nat"
        def _ipt(*args):
            return ipt(family, table, *args)
        def _ipm(*args):
            return ipt(family, "mangle", *args)
        chain = 'sshuttle-%s' % port
        # basic cleanup/setup of chains
        self.restore_firewall(port, family, udp, user, group)
        _ipt('-N', chain)
        _ipt('-F', chain)
        if user is not None or group is not None:
            margs = ['-I', 'OUTPUT', '1', '-m', 'owner']
            if user is not None:
                margs += ['--uid-owner', str(user)]
            if group is not None:
                margs += ['--gid-owner', str(group)]
            margs += ['-j', 'MARK', '--set-mark', str(port)]
            nonfatal(_ipm, *margs)
            args = '-m', 'mark', '--mark', str(port), '-j', chain
        else:
            args = '-j', chain
        _ipt('-I', 'OUTPUT', '1', *args)
        _ipt('-I', 'PREROUTING', '1', *args)
        # Redirect DNS traffic as requested. This includes routing traffic
        # to localhost DNS servers through sshuttle.
        for _, ip in [i for i in nslist if i[0] == family]:
            _ipt('-A', chain, '-j', 'REDIRECT',
                 '--dest', '%s' % ip,
                 '-p', 'udp',
                 '--dport', '53',
                 '--to-ports', str(dnsport))
        # create new subnet entries.
        for _, swidth, sexclude, snet, fport, lport \
                in sorted(subnets, key=subnet_weight, reverse=True):
            tcp_ports = ('-p', 'tcp')
            if fport:
                tcp_ports = tcp_ports + ('--dport', '%d:%d' % (fport, lport))
            if sexclude:
                _ipt('-A', chain, '-j', 'RETURN',
                     '--dest', '%s/%s' % (snet, swidth),
                     *tcp_ports)
            else:
                _ipt('-A', chain, '-j', 'REDIRECT',
                     '--dest', '%s/%s' % (snet, swidth),
                     *(tcp_ports + ('--to-ports', str(port))))
        # Don't route any remaining local traffic through sshuttle.
        _ipt('-A', chain, '-j', 'RETURN',
             '-m', 'addrtype',
             '--dst-type', 'LOCAL')
    def restore_firewall(self, port, family, udp, user, group):
        # only ipv4 supported with NAT
        if family != socket.AF_INET and family != socket.AF_INET6:
            raise Exception(
                'Address family "%s" unsupported by nat method_name'
                % family_to_string(family))
        if udp:
            raise Exception("UDP not supported by nat method_name")
        table = "nat"
        def _ipt(*args):
            return ipt(family, table, *args)
        def _ipm(*args):
            return ipt(family, "mangle", *args)
        chain = 'sshuttle-%s' % port
        # basic cleanup/setup of chains
        if ipt_chain_exists(family, table, chain):
            if user is not None or group is not None:
                margs = ['-D', 'OUTPUT', '-m', 'owner']
                if user is not None:
                    margs += ['--uid-owner', str(user)]
                if group is not None:
                    margs += ['--gid-owner', str(group)]
                margs += ['-j', 'MARK', '--set-mark', str(port)]
                nonfatal(_ipm, *margs)
                args = '-m', 'mark', '--mark', str(port), '-j', chain
            else:
                args = '-j', chain
            nonfatal(_ipt, '-D', 'OUTPUT', *args)
            nonfatal(_ipt, '-D', 'PREROUTING', *args)
            nonfatal(_ipt, '-F', chain)
            _ipt('-X', chain)
    def get_supported_features(self):
        result = super(Method, self).get_supported_features()
        result.user = True
        result.ipv6 = True
        result.group = True
        return result
    def is_supported(self):
        if which("iptables"):
            return True
        debug2("nat method not supported because 'iptables' command "
               "is missing.")
        return False
--- a/sshuttle/methods/nft.py
+++ b/sshuttle/methods/nft.py
@ -1,114 +0,0 @@
 import socket
 from sshuttle.firewall import subnet_weight
 from sshuttle.linux import nft, nonfatal
 from sshuttle.methods import BaseMethod
 from sshuttle.helpers import debug2, which
 class Method(BaseMethod):
    # We name the chain based on the transproxy port number so that it's
    # possible to run multiple copies of sshuttle at the same time.  Of course,
    # the multiple copies shouldn't have overlapping subnets, or only the most-
    # recently-started one will win (because we use "-I OUTPUT 1" instead of
    # "-A OUTPUT").
    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
                       user, group, tmark):
        if udp:
            raise Exception("UDP not supported by nft")
        if family == socket.AF_INET:
            table = 'sshuttle-ipv4-%s' % port
        if family == socket.AF_INET6:
            table = 'sshuttle-ipv6-%s' % port
        def _nft(action, *args):
            return nft(family, table, action, *args)
        chain = table
        # basic cleanup/setup of chains
        _nft('add table', '')
        _nft('add chain', 'prerouting',
             '{ type nat hook prerouting priority -100; policy accept; }')
        _nft('add chain', 'output',
             '{ type nat hook output priority -100; policy accept; }')
        _nft('add chain', chain)
        _nft('flush chain', chain)
        _nft('add rule', 'output jump %s' % chain)
        _nft('add rule', 'prerouting jump %s' % chain)
        # setup_firewall() gets called separately for ipv4 and ipv6. Make sure
        # we only handle the version that we expect to.
        if family == socket.AF_INET:
            _nft('add rule', chain, 'meta', 'nfproto', '!=', 'ipv4', 'return')
        else:
            _nft('add rule', chain, 'meta', 'nfproto', '!=', 'ipv6', 'return')
        # Strings to use below to simplify our code
        if family == socket.AF_INET:
            ip_version_l = 'ipv4'
            ip_version = 'ip'
        elif family == socket.AF_INET6:
            ip_version_l = 'ipv6'
            ip_version = 'ip6'
        # Redirect DNS traffic as requested. This includes routing traffic
        # to localhost DNS servers through sshuttle.
        for _, ip in [i for i in nslist if i[0] == family]:
            _nft('add rule', chain, ip_version,
                 'daddr %s' % ip, 'udp dport 53',
                 ('redirect to :' + str(dnsport)))
        # Don't route any remaining local traffic through sshuttle
        _nft('add rule', chain, 'fib daddr type local return')
        # create new subnet entries.
        for _, swidth, sexclude, snet, fport, lport \
                in sorted(subnets, key=subnet_weight, reverse=True):
            # match using nfproto as described at
            # https://superuser.com/questions/1560376/match-ipv6-protocol-using-nftables
            if fport and fport != lport:
                tcp_ports = ('meta', 'nfproto', ip_version_l, 'tcp',
                             'dport', '{ %d-%d }' % (fport, lport))
            elif fport and fport == lport:
                tcp_ports = ('meta', 'nfproto', ip_version_l, 'tcp',
                             'dport', '%d' % (fport))
            else:
                tcp_ports = ('meta', 'nfproto', ip_version_l,
                             'meta', 'l4proto', 'tcp')
            if sexclude:
                _nft('add rule', chain, *(tcp_ports + (
                     ip_version, 'daddr %s/%s' % (snet, swidth), 'return')))
            else:
                _nft('add rule', chain, *(tcp_ports + (
                    ip_version, 'daddr %s/%s' % (snet, swidth),
                    ('redirect to :' + str(port)))))
    def restore_firewall(self, port, family, udp, user, group):
        if udp:
            raise Exception("UDP not supported by nft method_name")
        if family == socket.AF_INET:
            table = 'sshuttle-ipv4-%s' % port
        if family == socket.AF_INET6:
            table = 'sshuttle-ipv6-%s' % port
        def _nft(action, *args):
            return nft(family, table, action, *args)
        # basic cleanup/setup of chains
        nonfatal(_nft, 'delete table', '')
    def get_supported_features(self):
        result = super(Method, self).get_supported_features()
        result.ipv6 = True
        return result
    def is_supported(self):
        if which("nft"):
            return True
        debug2("nft method not supported because 'nft' command is missing.")
        return False
--- a/sshuttle/methods/pf.py
+++ b/sshuttle/methods/pf.py
@ -1,503 +0,0 @@
 import os
 import sys
 import platform
 import re
 import socket
 import errno
 import struct
 import subprocess as ssubprocess
 import shlex
 from fcntl import ioctl
 from ctypes import c_char, c_uint8, c_uint16, c_uint32, Union, Structure, \
    sizeof, addressof, memmove
 from sshuttle.firewall import subnet_weight
 from sshuttle.helpers import log, debug1, debug2, debug3, Fatal, \
     family_to_string, get_env, which
 from sshuttle.methods import BaseMethod
 _pf_context = {
    'started_by_sshuttle': 0,
    'loaded_by_sshuttle': True,
    'Xtoken': []
 }
 _pf_fd = None
 class Generic(object):
    MAXPATHLEN = 1024
    PF_CHANGE_ADD_TAIL = 2
    PF_CHANGE_GET_TICKET = 6
    PF_PASS = 0
    PF_RDR = 8
    PF_OUT = 2
    ACTION_OFFSET = 0
    POOL_TICKET_OFFSET = 8
    ANCHOR_CALL_OFFSET = 1040
    class pf_addr(Structure):
        class _pfa(Union):
            _fields_ = [("v4", c_uint32),      # struct in_addr
                        ("v6", c_uint32 * 4),  # struct in6_addr
                        ("addr8", c_uint8 * 16),
                        ("addr16", c_uint16 * 8),
                        ("addr32", c_uint32 * 4)]
        _fields_ = [("pfa", _pfa)]
        _anonymous_ = ("pfa",)
    def __init__(self):
        self.status = b''
        self.pfioc_pooladdr = c_char * 1136
        self.DIOCNATLOOK = (
            (0x40000000 | 0x80000000) |
            ((sizeof(self.pfioc_natlook) & 0x1fff) << 16) |
            ((ord('D')) << 8) | (23))
        self.DIOCCHANGERULE = (
            (0x40000000 | 0x80000000) |
            ((sizeof(self.pfioc_rule) & 0x1fff) << 16) |
            ((ord('D')) << 8) | (26))
        self.DIOCBEGINADDRS = (
            (0x40000000 | 0x80000000) |
            ((sizeof(self.pfioc_pooladdr) & 0x1fff) << 16) |
            ((ord('D')) << 8) | (51))
    def enable(self):
        if b'INFO:\nStatus: Disabled' in self.status:
            pfctl('-e')
            _pf_context['started_by_sshuttle'] += 1
    @staticmethod
    def disable(anchor):
        pfctl('-a %s -F all' % anchor)
        if _pf_context['started_by_sshuttle'] == 1:
            pfctl('-d')
        _pf_context['started_by_sshuttle'] -= 1
    def query_nat(self, family, proto, src_ip, src_port, dst_ip, dst_port):
        [proto, family, src_port, dst_port] = [
            int(v) for v in [proto, family, src_port, dst_port]]
        packed_src_ip = socket.inet_pton(family, src_ip)
        packed_dst_ip = socket.inet_pton(family, dst_ip)
        assert len(packed_src_ip) == len(packed_dst_ip)
        length = len(packed_src_ip)
        pnl = self.pfioc_natlook()
        pnl.proto = proto
        pnl.direction = self.PF_OUT
        pnl.af = family
        memmove(addressof(pnl.saddr), packed_src_ip, length)
        memmove(addressof(pnl.daddr), packed_dst_ip, length)
        self._add_natlook_ports(pnl, src_port, dst_port)
        ioctl(pf_get_dev(), self.DIOCNATLOOK,
              (c_char * sizeof(pnl)).from_address(addressof(pnl)))
        ip = socket.inet_ntop(
            pnl.af, (c_char * length).from_address(addressof(pnl.rdaddr)).raw)
        port = socket.ntohs(self._get_natlook_port(pnl.rdxport))
        return (ip, port)
    @staticmethod
    def _add_natlook_ports(pnl, src_port, dst_port):
        pnl.sxport = socket.htons(src_port)
        pnl.dxport = socket.htons(dst_port)
    @staticmethod
    def _get_natlook_port(xport):
        return xport
    def add_anchors(self, anchor, status=None):
        if status is None:
            status = pfctl('-s all')[0]
        self.status = status
        if ('\nanchor "%s"' % anchor).encode('ASCII') not in status:
            self._add_anchor_rule(self.PF_PASS, anchor.encode('ASCII'))
    def _add_anchor_rule(self, kind, name, pr=None):
        if pr is None:
            pr = self.pfioc_rule()
        memmove(addressof(pr) + self.ANCHOR_CALL_OFFSET, name,
                min(self.MAXPATHLEN, len(name)))  # anchor_call = name
        memmove(addressof(pr) + self.RULE_ACTION_OFFSET,
                struct.pack('I', kind), 4)  # rule.action = kind
        memmove(addressof(pr) + self.ACTION_OFFSET,
                struct.pack('I', self.PF_CHANGE_GET_TICKET),
                4)  # action = PF_CHANGE_GET_TICKET
        ioctl(pf_get_dev(), pf.DIOCCHANGERULE, pr)
        memmove(addressof(pr) + self.ACTION_OFFSET,
                struct.pack('I', self.PF_CHANGE_ADD_TAIL),
                4)  # action = PF_CHANGE_ADD_TAIL
        ioctl(pf_get_dev(), pf.DIOCCHANGERULE, pr)
    @staticmethod
    def _inet_version(family):
        return b'inet' if family == socket.AF_INET else b'inet6'
    @staticmethod
    def _lo_addr(family):
        return b'127.0.0.1' if family == socket.AF_INET else b'::1'
    @staticmethod
    def add_rules(anchor, rules):
        assert isinstance(rules, bytes)
        debug3("rules:\n" + rules.decode("ASCII"))
        pfctl('-a %s -f /dev/stdin' % anchor, rules)
    @staticmethod
    def has_skip_loopback():
        return b'skip' in pfctl('-s Interfaces -i lo -v')[0]
 class FreeBsd(Generic):
    RULE_ACTION_OFFSET = 2968
    def __new__(cls):
        class pfioc_natlook(Structure):
            pf_addr = Generic.pf_addr
            _fields_ = [("saddr", pf_addr),
                        ("daddr", pf_addr),
                        ("rsaddr", pf_addr),
                        ("rdaddr", pf_addr),
                        ("sxport", c_uint16),
                        ("dxport", c_uint16),
                        ("rsxport", c_uint16),
                        ("rdxport", c_uint16),
                        ("af", c_uint8),                      # sa_family_t
                        ("proto", c_uint8),
                        ("proto_variant", c_uint8),
                        ("direction", c_uint8)]
        freebsd = Generic.__new__(cls)
        freebsd.pfioc_rule = c_char * 3040
        freebsd.pfioc_natlook = pfioc_natlook
        return freebsd
    def enable(self):
        returncode = ssubprocess.call(['kldload', 'pf'], env=get_env())
        # No env: No output.
        super(FreeBsd, self).enable()
        if returncode == 0:
            _pf_context['loaded_by_sshuttle'] = True
    def disable(self, anchor):
        super(FreeBsd, self).disable(anchor)
        if _pf_context['loaded_by_sshuttle'] and \
                _pf_context['started_by_sshuttle'] == 0:
            ssubprocess.call(['kldunload', 'pf'], env=get_env())
            # No env: No output.
    def add_anchors(self, anchor):
        status = pfctl('-s all')[0]
        if ('\nrdr-anchor "%s"' % anchor).encode('ASCII') not in status:
            self._add_anchor_rule(self.PF_RDR, anchor.encode('ASCII'))
        super(FreeBsd, self).add_anchors(anchor, status=status)
    def _add_anchor_rule(self, kind, name, pr=None):
        pr = pr or self.pfioc_rule()
        ppa = self.pfioc_pooladdr()
        ioctl(pf_get_dev(), self.DIOCBEGINADDRS, ppa)
        # pool ticket
        memmove(addressof(pr) + self.POOL_TICKET_OFFSET, ppa[4:8], 4)
        super(FreeBsd, self)._add_anchor_rule(kind, name, pr=pr)
    def add_rules(self, anchor, includes, port, dnsport, nslist, family):
        inet_version = self._inet_version(family)
        lo_addr = self._lo_addr(family)
        tables = []
        translating_rules = [
            b'rdr pass on lo0 %s proto tcp from ! %s to %s '
            b'-> %s port %r' % (inet_version, lo_addr, subnet, lo_addr, port)
            for exclude, subnet in includes if not exclude
        ]
        filtering_rules = [
            b'pass out route-to lo0 %s proto tcp '
            b'to %s keep state' % (inet_version, subnet)
            if not exclude else
            b'pass out %s proto tcp to %s' % (inet_version, subnet)
            for exclude, subnet in includes
        ]
        if nslist:
            tables.append(
                b'table <dns_servers> {%s}' %
                b','.join([ns[1].encode("ASCII") for ns in nslist]))
            translating_rules.append(
                b'rdr pass on lo0 %s proto udp to <dns_servers> '
                b'port 53 -> %s port %r' % (inet_version, lo_addr, dnsport))
            filtering_rules.append(
                b'pass out route-to lo0 %s proto udp to '
                b'<dns_servers> port 53 keep state' % inet_version)
        rules = b'\n'.join(tables + translating_rules + filtering_rules) \
                + b'\n'
        super(FreeBsd, self).add_rules(anchor, rules)
 class OpenBsd(Generic):
    POOL_TICKET_OFFSET = 4
    RULE_ACTION_OFFSET = 3324
    ANCHOR_CALL_OFFSET = 1036
    def __init__(self):
        class pfioc_natlook(Structure):
            pf_addr = Generic.pf_addr
            _fields_ = [("saddr", pf_addr),
                        ("daddr", pf_addr),
                        ("rsaddr", pf_addr),
                        ("rdaddr", pf_addr),
                        ("rdomain", c_uint16),
                        ("rrdomain", c_uint16),
                        ("sxport", c_uint16),
                        ("dxport", c_uint16),
                        ("rsxport", c_uint16),
                        ("rdxport", c_uint16),
                        ("af", c_uint8),                      # sa_family_t
                        ("proto", c_uint8),
                        ("proto_variant", c_uint8),
                        ("direction", c_uint8)]
        self.pfioc_rule = c_char * 3408
        self.pfioc_natlook = pfioc_natlook
        super(OpenBsd, self).__init__()
    def add_anchors(self, anchor):
        # before adding anchors and rules we must override the skip lo
        # that comes by default in openbsd pf.conf so the rules we will add,
        # which rely on translating/filtering packets on lo, can work
        if self.has_skip_loopback():
            pfctl('-f /dev/stdin', b'match on lo\n')
        super(OpenBsd, self).add_anchors(anchor)
    def add_rules(self, anchor, includes, port, dnsport, nslist, family):
        inet_version = self._inet_version(family)
        lo_addr = self._lo_addr(family)
        tables = []
        translating_rules = [
            b'pass in on lo0 %s proto tcp to %s '
            b'divert-to %s port %r' % (inet_version, subnet, lo_addr, port)
            for exclude, subnet in includes if not exclude
        ]
        filtering_rules = [
            b'pass out %s proto tcp to %s '
            b'route-to lo0 keep state' % (inet_version, subnet)
            if not exclude else
            b'pass out %s proto tcp to %s' % (inet_version, subnet)
            for exclude, subnet in includes
        ]
        if nslist:
            tables.append(
                b'table <dns_servers> {%s}' %
                b','.join([ns[1].encode("ASCII") for ns in nslist]))
            translating_rules.append(
                b'pass in on lo0 %s proto udp to <dns_servers> port 53 '
                b'rdr-to %s port %r' % (inet_version, lo_addr, dnsport))
            filtering_rules.append(
                b'pass out %s proto udp to <dns_servers> port 53 '
                b'route-to lo0 keep state' % inet_version)
        rules = b'\n'.join(tables + translating_rules + filtering_rules) \
                + b'\n'
        super(OpenBsd, self).add_rules(anchor, rules)
 class Darwin(FreeBsd):
    RULE_ACTION_OFFSET = 3068
    def __init__(self):
        class pf_state_xport(Union):
            _fields_ = [("port", c_uint16),
                        ("call_id", c_uint16),
                        ("spi", c_uint32)]
        class pfioc_natlook(Structure):
            pf_addr = Generic.pf_addr
            _fields_ = [("saddr", pf_addr),
                        ("daddr", pf_addr),
                        ("rsaddr", pf_addr),
                        ("rdaddr", pf_addr),
                        ("sxport", pf_state_xport),
                        ("dxport", pf_state_xport),
                        ("rsxport", pf_state_xport),
                        ("rdxport", pf_state_xport),
                        ("af", c_uint8),                      # sa_family_t
                        ("proto", c_uint8),
                        ("proto_variant", c_uint8),
                        ("direction", c_uint8)]
        self.pfioc_rule = c_char * 3104
        self.pfioc_natlook = pfioc_natlook
        super(Darwin, self).__init__()
    def enable(self):
        o = pfctl('-E')
        _pf_context['Xtoken'].append(re.search(b'Token : (.+)', o[1]).group(1))
    def disable(self, anchor):
        pfctl('-a %s -F all' % anchor)
        if _pf_context['Xtoken']:
            pfctl('-X %s' % _pf_context['Xtoken'].pop().decode("ASCII"))
    def add_anchors(self, anchor):
        # before adding anchors and rules we must override the skip lo
        # that in some cases ends up in the chain so the rules we will add,
        # which rely on translating/filtering packets on lo, can work
        if self.has_skip_loopback():
            pfctl('-f /dev/stdin', b'pass on lo\n')
        super(Darwin, self).add_anchors(anchor)
    def _add_natlook_ports(self, pnl, src_port, dst_port):
        pnl.sxport.port = socket.htons(src_port)
        pnl.dxport.port = socket.htons(dst_port)
    def _get_natlook_port(self, xport):
        return xport.port
 class PfSense(FreeBsd):
    RULE_ACTION_OFFSET = 3040
    def __init__(self):
        self.pfioc_rule = c_char * 3112
        super(PfSense, self).__init__()
 if sys.platform == 'darwin':
    pf = Darwin()
 elif sys.platform.startswith('openbsd'):
    pf = OpenBsd()
 elif platform.version().endswith('pfSense'):
    pf = PfSense()
 else:
    pf = FreeBsd()
 def pfctl(args, stdin=None):
    argv = ['pfctl'] + shlex.split(args)
    debug1('>> %s' % ' '.join(argv))
    p = ssubprocess.Popen(argv, stdin=ssubprocess.PIPE,
                          stdout=ssubprocess.PIPE,
                          stderr=ssubprocess.PIPE,
                          env=get_env())
    o = p.communicate(stdin)
    if p.returncode:
        log('%r returned %d, stdout and stderr follows: ' %
            (argv, p.returncode))
        log("stdout:\n%s" % o[0].decode("ascii"))
        log("stderr:\n%s" % o[1].decode("ascii"))
        raise Fatal('%r returned %d' % (argv, p.returncode))
    return o
 def pf_get_dev():
    global _pf_fd
    if _pf_fd is None:
        _pf_fd = os.open('/dev/pf', os.O_RDWR)
    return _pf_fd
 def pf_get_anchor(family, port):
    return 'sshuttle%s-%d' % ('' if family == socket.AF_INET else '6', port)
 class Method(BaseMethod):
    def get_supported_features(self):
        result = super(Method, self).get_supported_features()
        result.ipv6 = True
        return result
    def get_tcp_dstip(self, sock):
        pfile = self.firewall.pfile
        try:
            peer = sock.getpeername()
        except socket.error:
            _, e = sys.exc_info()[:2]
            if e.args[0] == errno.EINVAL:
                return sock.getsockname()
        proxy = sock.getsockname()
        argv = (sock.family, socket.IPPROTO_TCP,
                peer[0].encode("ASCII"), peer[1],
                proxy[0].encode("ASCII"), proxy[1])
        out_line = b"QUERY_PF_NAT %d,%d,%s,%d,%s,%d\n" % argv
        pfile.write(out_line)
        pfile.flush()
        in_line = pfile.readline()
        debug2(out_line.decode("ASCII") + ' > ' + in_line.decode("ASCII"))
        if in_line.startswith(b'QUERY_PF_NAT_SUCCESS '):
            (ip, port) = in_line[21:].split(b',')
            return (ip.decode("ASCII"), int(port))
        return sock.getsockname()
    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
                       user, group, tmark):
        if family not in [socket.AF_INET, socket.AF_INET6]:
            raise Exception(
                'Address family "%s" unsupported by pf method_name'
                % family_to_string(family))
        if udp:
            raise Exception("UDP not supported by pf method_name")
        if subnets:
            includes = []
            # If a given subnet is both included and excluded, list the
            # exclusion first; the table will ignore the second, opposite
            # definition
            for _, swidth, sexclude, snet, fport, lport \
                    in sorted(subnets, key=subnet_weight):
                includes.append((sexclude, b"%s/%d%s" % (
                    snet.encode("ASCII"),
                    swidth,
                    b" port %d:%d" % (fport, lport) if fport else b"")))
        anchor = pf_get_anchor(family, port)
        pf.add_anchors(anchor)
        pf.add_rules(anchor, includes, port, dnsport, nslist, family)
        pf.enable()
    def restore_firewall(self, port, family, udp, user, group):
        if family not in [socket.AF_INET, socket.AF_INET6]:
            raise Exception(
                'Address family "%s" unsupported by pf method_name'
                % family_to_string(family))
        if udp:
            raise Exception("UDP not supported by pf method_name")
        pf.disable(pf_get_anchor(family, port))
    def firewall_command(self, line):
        if line.startswith('QUERY_PF_NAT '):
            try:
                dst = pf.query_nat(*(line[13:].split(',')))
                sys.stdout.write('QUERY_PF_NAT_SUCCESS %s,%r\n' % dst)
            except IOError as e:
                sys.stdout.write('QUERY_PF_NAT_FAILURE %s\n' % e)
            sys.stdout.flush()
            return True
        else:
            return False
    def is_supported(self):
        if which("pfctl"):
            return True
        debug2("pf method not supported because 'pfctl' command is missing.")
        return False
--- a/sshuttle/methods/tproxy.py
+++ b/sshuttle/methods/tproxy.py
@ -1,266 +0,0 @@
 import struct
 from sshuttle.firewall import subnet_weight
 from sshuttle.helpers import family_to_string
 from sshuttle.linux import ipt, ipt_chain_exists
 from sshuttle.methods import BaseMethod
 from sshuttle.helpers import debug1, debug2, debug3, Fatal, which
 import socket
 import os
 IP_TRANSPARENT = 19
 IP_ORIGDSTADDR = 20
 IP_RECVORIGDSTADDR = IP_ORIGDSTADDR
 SOL_IPV6 = 41
 IPV6_ORIGDSTADDR = 74
 IPV6_RECVORIGDSTADDR = IPV6_ORIGDSTADDR
 def recv_udp(listener, bufsize):
    debug3('Accept UDP python using recvmsg.')
    data, ancdata, _, srcip = listener.recvmsg(
        4096, socket.CMSG_SPACE(24))
    dstip = None
    family = None
    for cmsg_level, cmsg_type, cmsg_data in ancdata:
        if cmsg_level == socket.SOL_IP and cmsg_type == IP_ORIGDSTADDR:
            family, port = struct.unpack('=HH', cmsg_data[0:4])
            port = socket.htons(port)
            if family == socket.AF_INET:
                start = 4
                length = 4
            else:
                raise Fatal("Unsupported socket type '%s'" % family)
            ip = socket.inet_ntop(family, cmsg_data[start:start + length])
            dstip = (ip, port)
            break
        elif cmsg_level == SOL_IPV6 and cmsg_type == IPV6_ORIGDSTADDR:
            family, port = struct.unpack('=HH', cmsg_data[0:4])
            port = socket.htons(port)
            if family == socket.AF_INET6:
                start = 8
                length = 16
            else:
                raise Fatal("Unsupported socket type '%s'" % family)
            ip = socket.inet_ntop(family, cmsg_data[start:start + length])
            dstip = (ip, port)
            break
    return (srcip, dstip, data)
 class Method(BaseMethod):
    def get_supported_features(self):
        result = super(Method, self).get_supported_features()
        result.ipv6 = True
        result.udp = True
        result.dns = True
        return result
    def get_tcp_dstip(self, sock):
        return sock.getsockname()
    def recv_udp(self, udp_listener, bufsize):
        srcip, dstip, data = recv_udp(udp_listener, bufsize)
        if not dstip:
            debug1(
                "-- ignored UDP from %r: "
                "couldn't determine destination IP address\n" % (srcip,))
            return None
        return srcip, dstip, data
    def setsockopt_error(self, e):
        """The tproxy method needs root permissions to successfully
        set the IP_TRANSPARENT option on sockets. This method is
        called when we receive a PermissionError when trying to do
        so."""
        raise Fatal("Insufficient permissions for tproxy method.\n"
                    "Your effective UID is %d, not 0. Try rerunning as root.\n"
                    % os.geteuid())
    def send_udp(self, sock, srcip, dstip, data):
        if not srcip:
            debug1(
                "-- ignored UDP to %r: "
                "couldn't determine source IP address\n" % (dstip,))
            return
        sender = socket.socket(sock.family, socket.SOCK_DGRAM)
        sender.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        try:
            sender.setsockopt(socket.SOL_IP, IP_TRANSPARENT, 1)
        except PermissionError as e:
            self.setsockopt_error(e)
        sender.bind(srcip)
        sender.sendto(data, dstip)
        sender.close()
    def setup_tcp_listener(self, tcp_listener):
        try:
            tcp_listener.setsockopt(socket.SOL_IP, IP_TRANSPARENT, 1)
        except PermissionError as e:
            self.setsockopt_error(e)
    def setup_udp_listener(self, udp_listener):
        try:
            udp_listener.setsockopt(socket.SOL_IP, IP_TRANSPARENT, 1)
        except PermissionError as e:
            self.setsockopt_error(e)
        if udp_listener.v4 is not None:
            udp_listener.v4.setsockopt(
                socket.SOL_IP, IP_RECVORIGDSTADDR, 1)
        if udp_listener.v6 is not None:
            udp_listener.v6.setsockopt(SOL_IPV6, IPV6_RECVORIGDSTADDR, 1)
    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
                       user, group, tmark):
        if family not in [socket.AF_INET, socket.AF_INET6]:
            raise Exception(
                'Address family "%s" unsupported by tproxy method'
                % family_to_string(family))
        table = "mangle"
        def _ipt(*args):
            return ipt(family, table, *args)
        def _ipt_proto_ports(proto, fport, lport):
            return proto + ('--dport', '%d:%d' % (fport, lport)) \
                if fport else proto
        mark_chain = 'sshuttle-m-%s' % port
        tproxy_chain = 'sshuttle-t-%s' % port
        divert_chain = 'sshuttle-d-%s' % port
        # basic cleanup/setup of chains
        self.restore_firewall(port, family, udp, user, group)
        _ipt('-N', mark_chain)
        _ipt('-F', mark_chain)
        _ipt('-N', divert_chain)
        _ipt('-F', divert_chain)
        _ipt('-N', tproxy_chain)
        _ipt('-F', tproxy_chain)
        _ipt('-I', 'OUTPUT', '1', '-j', mark_chain)
        _ipt('-I', 'PREROUTING', '1', '-j', tproxy_chain)
        for _, ip in [i for i in nslist if i[0] == family]:
            _ipt('-A', mark_chain, '-j', 'MARK', '--set-mark', tmark,
                 '--dest', '%s/32' % ip,
                 '-m', 'udp', '-p', 'udp', '--dport', '53')
            _ipt('-A', tproxy_chain, '-j', 'TPROXY',
                 '--tproxy-mark', tmark,
                 '--dest', '%s/32' % ip,
                 '-m', 'udp', '-p', 'udp', '--dport', '53',
                 '--on-port', str(dnsport))
        # Don't have packets sent to any of our local IP addresses go
        # through the tproxy or mark chains (except DNS ones).
        #
        # Without this fix, if a large subnet is redirected through
        # sshuttle (i.e., 0/0), then the user may be unable to receive
        # UDP responses or connect to their own machine using an IP
        # besides (127.0.0.1). Prior to including these lines, the
        # documentation reminded the user to use -x to exclude their
        # own IP addresses to receive UDP responses if they are
        # redirecting a large subnet through sshuttle (i.e., 0/0).
        _ipt('-A', tproxy_chain, '-j', 'RETURN', '-m', 'addrtype',
             '--dst-type', 'LOCAL')
        _ipt('-A', mark_chain, '-j', 'RETURN', '-m', 'addrtype',
             '--dst-type', 'LOCAL')
        _ipt('-A', divert_chain, '-j', 'MARK', '--set-mark', tmark)
        _ipt('-A', divert_chain, '-j', 'ACCEPT')
        _ipt('-A', tproxy_chain, '-m', 'socket', '-j', divert_chain,
             '-m', 'tcp', '-p', 'tcp')
        if udp:
            _ipt('-A', tproxy_chain, '-m', 'socket', '-j', divert_chain,
                 '-m', 'udp', '-p', 'udp')
        for _, swidth, sexclude, snet, fport, lport \
                in sorted(subnets, key=subnet_weight, reverse=True):
            tcp_ports = ('-p', 'tcp')
            tcp_ports = _ipt_proto_ports(tcp_ports, fport, lport)
            if sexclude:
                _ipt('-A', mark_chain, '-j', 'RETURN',
                     '--dest', '%s/%s' % (snet, swidth),
                     '-m', 'tcp',
                     *tcp_ports)
                _ipt('-A', tproxy_chain, '-j', 'RETURN',
                     '--dest', '%s/%s' % (snet, swidth),
                     '-m', 'tcp',
                     *tcp_ports)
            else:
                _ipt('-A', mark_chain, '-j', 'MARK', '--set-mark', tmark,
                     '--dest', '%s/%s' % (snet, swidth),
                     '-m', 'tcp',
                     *tcp_ports)
                _ipt('-A', tproxy_chain, '-j', 'TPROXY',
                     '--tproxy-mark', tmark,
                     '--dest', '%s/%s' % (snet, swidth),
                     '-m', 'tcp',
                     *(tcp_ports + ('--on-port', str(port))))
            if udp:
                udp_ports = ('-p', 'udp')
                udp_ports = _ipt_proto_ports(udp_ports, fport, lport)
                if sexclude:
                    _ipt('-A', mark_chain, '-j', 'RETURN',
                         '--dest', '%s/%s' % (snet, swidth),
                         '-m', 'udp',
                         *udp_ports)
                    _ipt('-A', tproxy_chain, '-j', 'RETURN',
                         '--dest', '%s/%s' % (snet, swidth),
                         '-m', 'udp',
                         *udp_ports)
                else:
                    _ipt('-A', mark_chain, '-j', 'MARK', '--set-mark', tmark,
                         '--dest', '%s/%s' % (snet, swidth),
                         '-m', 'udp',
                         *udp_ports)
                    _ipt('-A', tproxy_chain, '-j', 'TPROXY',
                         '--tproxy-mark', tmark,
                         '--dest', '%s/%s' % (snet, swidth),
                         '-m', 'udp',
                         *(udp_ports + ('--on-port', str(port))))
    def restore_firewall(self, port, family, udp, user, group):
        if family not in [socket.AF_INET, socket.AF_INET6]:
            raise Exception(
                'Address family "%s" unsupported by tproxy method'
                % family_to_string(family))
        table = "mangle"
        def _ipt(*args):
            return ipt(family, table, *args)
        mark_chain = 'sshuttle-m-%s' % port
        tproxy_chain = 'sshuttle-t-%s' % port
        divert_chain = 'sshuttle-d-%s' % port
        # basic cleanup/setup of chains
        if ipt_chain_exists(family, table, mark_chain):
            _ipt('-D', 'OUTPUT', '-j', mark_chain)
            _ipt('-F', mark_chain)
            _ipt('-X', mark_chain)
        if ipt_chain_exists(family, table, tproxy_chain):
            _ipt('-D', 'PREROUTING', '-j', tproxy_chain)
            _ipt('-F', tproxy_chain)
            _ipt('-X', tproxy_chain)
        if ipt_chain_exists(family, table, divert_chain):
            _ipt('-F', divert_chain)
            _ipt('-X', divert_chain)
    def is_supported(self):
        if which("iptables") and which("ip6tables"):
            return True
        debug2("tproxy method not supported because 'iptables' "
               "or 'ip6tables' commands are missing.\n")
        return False
--- a/sshuttle/methods/windivert.py
+++ b/sshuttle/methods/windivert.py
@ -1,533 +0,0 @@
 import os
 import sys
 from ipaddress import ip_address, ip_network
 import threading
 from collections import namedtuple
 import socket
 import subprocess
 import re
 from multiprocessing import shared_memory
 from struct import Struct
 from functools import wraps
 from enum import IntEnum
 import time
 import traceback
 from sshuttle.methods import BaseMethod
 from sshuttle.helpers import log, debug3, debug1, debug2, get_verbose_level, Fatal
 try:
    # https://reqrypt.org/windivert-doc.html#divert_iphdr
    # https://www.reqrypt.org/windivert-changelog.txt
    import pydivert
 except ImportError:
    raise Exception("Could not import pydivert module. windivert requires https://pypi.org/project/pydivert")
 ConnectionTuple = namedtuple(
    "ConnectionTuple",
    ["protocol", "ip_version", "src_addr", "src_port", "dst_addr", "dst_port", "state_epoch", "state"],
 )
 WINDIVERT_MAX_CONNECTIONS = int(os.environ.get('WINDIVERT_MAX_CONNECTIONS', 1024))
 class IPProtocol(IntEnum):
    TCP = socket.IPPROTO_TCP
    UDP = socket.IPPROTO_UDP
    @property
    def filter(self):
        return "tcp" if self == IPProtocol.TCP else "udp"
 class IPFamily(IntEnum):
    IPv4 = socket.AF_INET
    IPv6 = socket.AF_INET6
    @staticmethod
    def from_ip_version(version):
        return IPFamily.IPv6 if version == 4 else IPFamily.IPv4
    @property
    def filter(self):
        return "ip" if self == socket.AF_INET else "ipv6"
    @property
    def version(self):
        return 4 if self == socket.AF_INET else 6
    @property
    def loopback_addr(self):
        return ip_address("127.0.0.1" if self == socket.AF_INET else "::1")
 class ConnState(IntEnum):
    TCP_SYN_SENT = 11  # SYN sent
    TCP_ESTABLISHED = 12  # SYN+ACK received
    TCP_FIN_WAIT_1 = 91  # FIN sent
    TCP_CLOSE_WAIT = 92  # FIN received
    @staticmethod
    def can_timeout(state):
        return state in (ConnState.TCP_SYN_SENT, ConnState.TCP_FIN_WAIT_1, ConnState.TCP_CLOSE_WAIT)
 def repr_pkt(p):
    try:
        direction = p.direction.name
        if p.is_loopback:
            direction += "/lo"
    except AttributeError:  # windiver > 2.0
        direction = 'OUT' if p.address.Outbound == 1 else 'IN'
        if p.address.Loopback == 1:
            direction += '/lo'
    r = f"{direction} {p.src_addr}:{p.src_port}->{p.dst_addr}:{p.dst_port}"
    if p.tcp:
        t = p.tcp
        r += f" {len(t.payload)}B ("
        r += "+".join(
            f.upper() for f in ("fin", "syn", "rst", "psh", "ack", "urg", "ece", "cwr", "ns") if getattr(t, f)
        )
        r += f") SEQ#{t.seq_num}"
        if t.ack:
            r += f" ACK#{t.ack_num}"
        r += f" WZ={t.window_size}"
    else:
        r += f" {p.udp=} {p.icmpv4=} {p.icmpv6=}"
    return f"<Pkt {r}>"
 def synchronized_method(lock):
    def decorator(method):
        @wraps(method)
        def wrapped(self, *args, **kwargs):
            with getattr(self, lock):
                return method(self, *args, **kwargs)
        return wrapped
    return decorator
 class ConnTrack:
    _instance = None
    def __new__(cls, *args, **kwargs):
        if not cls._instance:
            cls._instance = object.__new__(cls)
            return cls._instance
        raise RuntimeError("ConnTrack can not be instantiated multiple times")
    def __init__(self, name, max_connections=0) -> None:
        self.struct_full_tuple = Struct(">" + "".join(("B", "B", "16s", "H", "16s", "H", "L", "B")))
        self.struct_src_tuple = Struct(">" + "".join(("B", "B", "16s", "H")))
        self.struct_state_tuple = Struct(">" + "".join(("L", "B")))
        try:
            self.max_connections = max_connections
            self.shm_list = shared_memory.ShareableList(
                [bytes(self.struct_full_tuple.size) for _ in range(max_connections)], name=name
            )
            self.is_owner = True
            self.next_slot = 0
            self.used_slots = set()
            self.rlock = threading.RLock()
        except FileExistsError:
            self.is_owner = False
            self.shm_list = shared_memory.ShareableList(name=name)
            self.max_connections = len(self.shm_list)
        debug2(
            f"ConnTrack: is_owner={self.is_owner} cap={len(self.shm_list)} item_sz={self.struct_full_tuple.size}B"
            f"shm_name={self.shm_list.shm.name} shm_sz={self.shm_list.shm.size}B"
        )
    @synchronized_method("rlock")
    def add(self, proto, src_addr, src_port, dst_addr, dst_port, state):
        if not self.is_owner:
            raise RuntimeError("Only owner can mutate ConnTrack")
        if len(self.used_slots) >= self.max_connections:
            raise RuntimeError(f"No slot available in ConnTrack {len(self.used_slots)}/{self.max_connections}")
        if self.get(proto, src_addr, src_port):
            return
        for _ in range(self.max_connections):
            if self.next_slot not in self.used_slots:
                break
            self.next_slot = (self.next_slot + 1) % self.max_connections
        else:
            raise RuntimeError("No slot available in ConnTrack")  # should not be here
        src_addr = ip_address(src_addr)
        dst_addr = ip_address(dst_addr)
        assert src_addr.version == dst_addr.version
        ip_version = src_addr.version
        state_epoch = int(time.time())
        entry = (proto, ip_version, src_addr.packed, src_port, dst_addr.packed, dst_port, state_epoch, state)
        packed = self.struct_full_tuple.pack(*entry)
        self.shm_list[self.next_slot] = packed
        self.used_slots.add(self.next_slot)
        proto = IPProtocol(proto)
        debug3(
            f"ConnTrack: added ({proto.name} {src_addr}:{src_port}->{dst_addr}:{dst_port} @{state_epoch}:{state.name}) to "
            f"slot={self.next_slot} | #ActiveConn={len(self.used_slots)}"
        )
    @synchronized_method("rlock")
    def update(self, proto, src_addr, src_port, state):
        if not self.is_owner:
            raise RuntimeError("Only owner can mutate ConnTrack")
        src_addr = ip_address(src_addr)
        packed = self.struct_src_tuple.pack(proto, src_addr.version, src_addr.packed, src_port)
        for i in self.used_slots:
            if self.shm_list[i].startswith(packed):
                state_epoch = int(time.time())
                self.shm_list[i] = self.shm_list[i][:-5] + self.struct_state_tuple.pack(state_epoch, state)
                debug3(
                    f"ConnTrack: updated ({proto.name} {src_addr}:{src_port} @{state_epoch}:{state.name}) from slot={i} | "
                    f"#ActiveConn={len(self.used_slots)}"
                )
                return self._unpack(self.shm_list[i])
            else:
                debug3(
                    f"ConnTrack: ({proto.name} src={src_addr}:{src_port}) is not found to update to {state.name} | "
                    f"#ActiveConn={len(self.used_slots)}"
                )
    @synchronized_method("rlock")
    def remove(self, proto, src_addr, src_port):
        if not self.is_owner:
            raise RuntimeError("Only owner can mutate ConnTrack")
        src_addr = ip_address(src_addr)
        packed = self.struct_src_tuple.pack(proto, src_addr.version, src_addr.packed, src_port)
        for i in self.used_slots:
            if self.shm_list[i].startswith(packed):
                conn = self._unpack(self.shm_list[i])
                self.shm_list[i] = b""
                self.used_slots.remove(i)
                debug3(
                    f"ConnTrack: removed ({proto.name} src={src_addr}:{src_port}  state={conn.state.name}) from slot={i} | "
                    f"#ActiveConn={len(self.used_slots)}"
                )
                return conn
        else:
            debug3(
                f"ConnTrack: ({proto.name} src={src_addr}:{src_port}) is not found to remove |"
                f" #ActiveConn={len(self.used_slots)}"
            )
    def get(self, proto, src_addr, src_port):
        src_addr = ip_address(src_addr)
        packed = self.struct_src_tuple.pack(proto, src_addr.version, src_addr.packed, src_port)
        for entry in self.shm_list:
            if entry and entry.startswith(packed):
                return self._unpack(entry)
    def dump(self):
        for entry in self.shm_list:
            if not entry:
                continue
            conn = self._unpack(entry)
            proto, ip_version, src_addr, src_port, dst_addr, dst_port, state_epoch, state = conn
            log(f"{proto.name}/{ip_version} {src_addr}:{src_port} -> {dst_addr}:{dst_port}  {state.name}@{state_epoch}")
    @synchronized_method("rlock")
    def gc(self, connection_timeout_sec=15):
        # self.dump()
        now = int(time.time())
        n = 0
        for i in tuple(self.used_slots):
            state_packed = self.shm_list[i][-5:]
            (state_epoch, state) = self.struct_state_tuple.unpack(state_packed)
            if (now - state_epoch) < connection_timeout_sec:
                continue
            if ConnState.can_timeout(state):
                conn = self._unpack(self.shm_list[i])
                self.shm_list[i] = b""
                self.used_slots.remove(i)
                n += 1
                debug3(
                    f"ConnTrack: GC: removed ({conn.protocol.name} src={conn.src_addr}:{conn.src_port} state={conn.state.name})"
                    f" from slot={i} | #ActiveConn={len(self.used_slots)}"
                )
        debug3(f"ConnTrack: GC: collected {n} connections | #ActiveConn={len(self.used_slots)}")
    def _unpack(self, packed):
        (
            proto,
            ip_version,
            src_addr_packed,
            src_port,
            dst_addr_packed,
            dst_port,
            state_epoch,
            state,
        ) = self.struct_full_tuple.unpack(packed)
        dst_addr = ip_address(dst_addr_packed if ip_version == 6 else dst_addr_packed[:4]).exploded
        src_addr = ip_address(src_addr_packed if ip_version == 6 else src_addr_packed[:4]).exploded
        proto = IPProtocol(proto)
        state = ConnState(state)
        return ConnectionTuple(proto, ip_version, src_addr, src_port, dst_addr, dst_port, state_epoch, state)
    def __iter__(self):
        def conn_iter():
            for i in self.used_slots:
                yield self._unpack(self.shm_list[i])
        return conn_iter()
    def __repr__(self):
        return f"<ConnTrack(n={len(self.used_slots) if self.is_owner else '?'},cap={len(self.shm_list)},owner={self.is_owner})>"
 class Method(BaseMethod):
    network_config = {}
    def __init__(self, name):
        super().__init__(name)
    def _get_bind_address_for_port(self, port, family):
        proto = "TCPv6" if family.version == 6 else "TCP"
        for line in subprocess.check_output(["netstat", "-a", "-n", "-p", proto]).decode(errors='ignore').splitlines():
            try:
                _, local_addr, _, state, *_ = re.split(r"\s+", line.strip())
            except ValueError:
                continue
            port_suffix = ":" + str(port)
            if state == "LISTENING" and local_addr.endswith(port_suffix):
                return ip_address(local_addr[:-len(port_suffix)].strip("[]"))
        raise Fatal("Could not find listening address for {}/{}".format(port, proto))
    def setup_firewall(self, proxy_port, dnsport, nslist, family, subnets, udp, user, group, tmark):
        debug2(f"{proxy_port=}, {dnsport=}, {nslist=}, {family=}, {subnets=}, {udp=}, {user=}, {group=} {tmark=}")
        if nslist or user or udp or group:
            raise NotImplementedError("user, group, nslist, udp are not supported")
        family = IPFamily(family)
        proxy_ip = None
        # using loopback only proxy binding won't work with windivert.
        # See: https://github.com/basil00/Divert/issues/17#issuecomment-341100167 https://github.com/basil00/Divert/issues/82)
        # As a workaround, finding another interface ip instead. (client should not bind proxy to loopback address)
        proxy_bind_addr = self._get_bind_address_for_port(proxy_port, family)
        if proxy_bind_addr.is_loopback:
            raise Fatal("Windivert method requires proxy to be reachable by a non loopback address.")
        if not proxy_bind_addr.is_unspecified:
            proxy_ip = proxy_bind_addr
        else:
            local_addresses = [ip_address(info[4][0]) for info in socket.getaddrinfo(socket.gethostname(), 0, family=family)]
            for addr in local_addresses:
                if not addr.is_loopback and not addr.is_link_local:
                    proxy_ip = addr
                    break
            else:
                raise Fatal("Windivert method requires proxy to be reachable by a non loopback address."
                            f"No address found for {family.name} in {local_addresses}")
        debug2(f"Found non loopback address to connect to proxy: {proxy_ip}")
        subnet_addresses = []
        for (_, mask, exclude, network_addr, fport, lport) in subnets:
            if fport and lport:
                if lport > fport:
                    raise Fatal("lport must be less than or equal to fport")
                ports = (fport, lport)
            else:
                ports = None
            subnet_addresses.append((ip_network(f"{network_addr}/{mask}"), ports, exclude))
        self.network_config[family] = {
            "subnets": subnet_addresses,
            "nslist": nslist,
            "proxy_addr": (proxy_ip, proxy_port)
        }
    def wait_for_firewall_ready(self, sshuttle_pid):
        debug2(f"network_config={self.network_config}")
        self.conntrack = ConnTrack(f"sshuttle-windivert-{sshuttle_pid}", WINDIVERT_MAX_CONNECTIONS)
        if not self.conntrack.is_owner:
            raise Fatal("ConnTrack should be owner in wait_for_firewall_ready()")
        thread_target_funcs = (self._egress_divert, self._ingress_divert, self._connection_gc)
        ready_events = []
        for fn in thread_target_funcs:
            ev = threading.Event()
            ready_events.append(ev)
            def _target():
                try:
                    fn(ev.set)
                except Exception:
                    debug2(f"thread {fn.__name__} exiting due to: " + traceback.format_exc())
                    sys.stdin.close()  # this will exist main thread
                    sys.stdout.close()
            threading.Thread(name=fn.__name__, target=_target, daemon=True).start()
        for ev in ready_events:
            if not ev.wait(5):  # at most 5 sec
                raise Fatal("timeout in wait_for_firewall_ready()")
    def restore_firewall(self, port, family, udp, user, group):
        pass
    def get_supported_features(self):
        result = super(Method, self).get_supported_features()
        result.loopback_proxy_port = False
        result.user = False
        result.dns = False
        # ipv6 only able to support with Windivert 2.x due to bugs in filter parsing
        # TODO(nom3ad): Enable ipv6 once https://github.com/ffalcinelli/pydivert/pull/57 merged
        result.ipv6 = False
        return result
    def get_tcp_dstip(self, sock):
        if not hasattr(self, "conntrack"):
            self.conntrack = ConnTrack(f"sshuttle-windivert-{os.getpid()}")
            if self.conntrack.is_owner:
                raise Fatal("ConnTrack should not be owner in get_tcp_dstip()")
        src_addr, src_port = sock.getpeername()
        c = self.conntrack.get(IPProtocol.TCP, src_addr, src_port)
        if not c:
            return (src_addr, src_port)
        return (c.dst_addr, c.dst_port)
    def is_supported(self):
        if sys.platform == "win32":
            return True
        return False
    def _egress_divert(self, ready_cb):
        """divert outgoing packets to proxy"""
        proto = IPProtocol.TCP
        filter = f"outbound and {proto.filter}"
        af_filters = []
        for af, c in self.network_config.items():
            subnet_include_filters = []
            subnet_exclude_filters = []
            for ip_net, ports, exclude in c["subnets"]:
                first_ip = ip_net.network_address.exploded
                last_ip = ip_net.broadcast_address.exploded
                if first_ip == last_ip:
                    _subnet_filter = f"{af.filter}.DstAddr=={first_ip}"
                else:
                    _subnet_filter = f"{af.filter}.DstAddr>={first_ip} and {af.filter}.DstAddr<={last_ip}"
                if ports:
                    if ports[0] == ports[1]:
                        _subnet_filter += f" and {proto.filter}.DstPort=={ports[0]}"
                    else:
                        _subnet_filter += f" and tcp.DstPort>={ports[0]} and tcp.DstPort<={ports[1]}"
                (subnet_exclude_filters if exclude else subnet_include_filters).append(f"({_subnet_filter})")
            _af_filter = f"{af.filter}"
            if subnet_include_filters:
                _af_filter += f" and ({' or '.join(subnet_include_filters)})"
            if subnet_exclude_filters:
                # TODO(noma3ad) use not() operator with Windivert2 after upgrade
                _af_filter += f" and (({' or '.join(subnet_exclude_filters)})? false : true)"
            proxy_ip, proxy_port = c["proxy_addr"]
            # Avoids proxy outbound traffic getting directed to itself
            proxy_guard_filter = f"(({af.filter}.DstAddr=={proxy_ip.exploded} and tcp.DstPort=={proxy_port})? false : true)"
            _af_filter += f" and {proxy_guard_filter}"
            af_filters.append(_af_filter)
        if not af_filters:
            raise Fatal("At least one ipv4 or ipv6 subnet is expected")
        filter = f"{filter} and ({' or '.join(af_filters)})"
        debug1(f"[EGRESS] {filter=}")
        with pydivert.WinDivert(filter, layer=pydivert.Layer.NETWORK, flags=pydivert.Flag.DEFAULT) as w:
            proxy_ipv4, proxy_ipv6 = None, None
            if IPFamily.IPv4 in self.network_config:
                proxy_ipv4 = self.network_config[IPFamily.IPv4]["proxy_addr"]
                proxy_ipv4 = proxy_ipv4[0].exploded, proxy_ipv4[1]
            if IPFamily.IPv6 in self.network_config:
                proxy_ipv6 = self.network_config[IPFamily.IPv6]["proxy_addr"]
                proxy_ipv6 = proxy_ipv6[0].exploded, proxy_ipv6[1]
            ready_cb()
            verbose = get_verbose_level()
            for pkt in w:
                verbose >= 3 and debug3("[EGRESS] " + repr_pkt(pkt))
                if pkt.tcp.syn and not pkt.tcp.ack:
                    # SYN sent (start of 3-way handshake connection establishment from our side, we wait for SYN+ACK)
                    self.conntrack.add(
                        socket.IPPROTO_TCP,
                        pkt.src_addr,
                        pkt.src_port,
                        pkt.dst_addr,
                        pkt.dst_port,
                        ConnState.TCP_SYN_SENT,
                    )
                if pkt.tcp.fin:
                    # FIN sent (start of graceful close our side, and we wait for ACK)
                    self.conntrack.update(IPProtocol.TCP, pkt.src_addr, pkt.src_port, ConnState.TCP_FIN_WAIT_1)
                if pkt.tcp.rst:
                    # RST sent (initiate abrupt connection teardown from our side, so we don't expect any reply)
                    self.conntrack.remove(IPProtocol.TCP, pkt.src_addr, pkt.src_port)
                # DNAT
                if pkt.ipv4 and proxy_ipv4:
                    pkt.dst_addr, pkt.tcp.dst_port = proxy_ipv4
                if pkt.ipv6 and proxy_ipv6:
                    pkt.dst_addr, pkt.tcp.dst_port = proxy_ipv6
                # XXX: If we set loopback proxy address (DNAT), then we should do SNAT as well
                #  by setting src_addr to loopback address.
                # Otherwise injecting packet will be ignored by Windows network stack
                #   as they packet has to cross public to private address space.
                # See: https://github.com/basil00/Divert/issues/82
                # Managing SNAT is more trickier, as we have to restore the original source IP address for reply packets.
                # >>> pkt.dst_addr = proxy_ipv4
                w.send(pkt, recalculate_checksum=True)
    def _ingress_divert(self, ready_cb):
        """handles incoming packets from proxy"""
        proto = IPProtocol.TCP
        # Windivert treats all local process traffic as outbound, regardless of origin external/loopback iface
        direction = "outbound"
        proxy_addr_filters = []
        for af, c in self.network_config.items():
            if not c["subnets"]:
                continue
            proxy_ip, proxy_port = c["proxy_addr"]
            # "ip.SrcAddr=={hex(int(proxy_ip))}" # only Windivert >=2 supports this
            proxy_addr_filters.append(f"{af.filter}.SrcAddr=={proxy_ip.exploded} and tcp.SrcPort=={proxy_port}")
        if not proxy_addr_filters:
            raise Fatal("At least one ipv4 or ipv6 address is expected")
        filter = f"{direction} and {proto.filter} and ({' or '.join(proxy_addr_filters)})"
        debug1(f"[INGRESS] {filter=}")
        with pydivert.WinDivert(filter, layer=pydivert.Layer.NETWORK, flags=pydivert.Flag.DEFAULT) as w:
            ready_cb()
            verbose = get_verbose_level()
            for pkt in w:
                verbose >= 3 and debug3("[INGRESS] " + repr_pkt(pkt))
                if pkt.tcp.syn and pkt.tcp.ack:
                    # SYN+ACK received (connection established from proxy
                    conn = self.conntrack.update(IPProtocol.TCP, pkt.dst_addr, pkt.dst_port, ConnState.TCP_ESTABLISHED)
                elif pkt.tcp.rst:
                    # RST received - Abrupt connection teardown initiated by proxy. Don't expect anymore packets
                    conn = self.conntrack.remove(IPProtocol.TCP, pkt.dst_addr, pkt.dst_port)
                # https://wiki.wireshark.org/TCP-4-times-close.md
                elif pkt.tcp.fin and pkt.tcp.ack:
                    # FIN+ACK received (Passive close by proxy. Don't expect any more packets. proxy expects an ACK)
                    conn = self.conntrack.remove(IPProtocol.TCP, pkt.dst_addr, pkt.dst_port)
                elif pkt.tcp.fin:
                    # FIN received (proxy initiated graceful close.  Expect a final ACK for a FIN packet)
                    conn = self.conntrack.update(IPProtocol.TCP, pkt.dst_addr, pkt.dst_port, ConnState.TCP_CLOSE_WAIT)
                else:
                    # data fragments and ACKs
                    conn = self.conntrack.get(socket.IPPROTO_TCP, pkt.dst_addr, pkt.dst_port)
                if not conn:
                    verbose >= 2 and debug2("Unexpected packet: " + repr_pkt(pkt))
                    continue
                pkt.src_addr = conn.dst_addr
                pkt.tcp.src_port = conn.dst_port
                w.send(pkt, recalculate_checksum=True)
    def _connection_gc(self, ready_cb):
        ready_cb()
        while True:
            time.sleep(5)
            self.conntrack.gc()
--- a/sshuttle/namespace.py
+++ b/sshuttle/namespace.py
@ -1,40 +0,0 @@
 import os
 import ctypes
 import ctypes.util
 from sshuttle.helpers import Fatal, debug1, debug2
 CLONE_NEWNET = 0x40000000
 NETNS_RUN_DIR = "/var/run/netns"
 def enter_namespace(namespace, namespace_pid):
    if namespace:
        namespace_dir = f'{NETNS_RUN_DIR}/{namespace}'
    else:
        namespace_dir = f'/proc/{namespace_pid}/ns/net'
    if not os.path.exists(namespace_dir):
        raise Fatal('The namespace %r does not exists.' % namespace_dir)
    debug2('loading libc')
    libc = ctypes.CDLL(ctypes.util.find_library("c"), use_errno=True)
    default_errcheck = libc.setns.errcheck
    def errcheck(ret, *args):
        if ret == -1:
            e = ctypes.get_errno()
            raise Fatal(e, os.strerror(e))
        if default_errcheck:
            return default_errcheck(ret, *args)
    libc.setns.errcheck = errcheck  # type: ignore
    debug1('Entering namespace %r' % namespace_dir)
    with open(namespace_dir) as fd:
        libc.setns(fd.fileno(), CLONE_NEWNET)
    debug1('Namespace %r successfully set' % namespace_dir)
--- a/sshuttle/options.py
+++ b/sshuttle/options.py
@ -1,488 +0,0 @@
 import re
 import socket
 import sys
 from argparse import ArgumentParser, Action, ArgumentTypeError as Fatal
 from sshuttle import __version__
 # Subnet file, supporting empty lines and hash-started comment lines
 def parse_subnetport_file(s):
    try:
        handle = open(s, 'r')
    except OSError:
        raise Fatal('Unable to open subnet file: %s' % s)
    raw_config_lines = handle.readlines()
    subnets = []
    for _, line in enumerate(raw_config_lines):
        line = line.strip()
        if not line:
            continue
        if line[0] == '#':
            continue
        subnets.append(parse_subnetport(line))
    return subnets
 # 1.2.3.4/5:678, 1.2.3.4:567, 1.2.3.4/16 or just 1.2.3.4
 # [1:2::3/64]:456, [1:2::3]:456, 1:2::3/64 or just 1:2::3
 # example.com:123 or just example.com
 #
 # In addition, the port number can be specified as a range:
 # 1.2.3.4:8000-8080.
 #
 # Can return multiple matches if the domain name used in the request
 # has multiple IP addresses.
 def parse_subnetport(s):
    if s.count(':') > 1:
        rx = r'(?:\[?(?:\*\.)?([\w\:]+)(?:/(\d+))?]?)(?::(\d+)(?:-(\d+))?)?$'
    else:
        rx = r'((?:\*\.)?[\w\.\-]+)(?:/(\d+))?(?::(\d+)(?:-(\d+))?)?$'
    m = re.match(rx, s)
    if not m:
        raise Fatal('%r is not a valid address/mask:port format' % s)
    # Ports range from fport to lport. If only one port is specified,
    # fport is defined and lport is None.
    #
    # cidr is the mask defined with the slash notation
    host, cidr, fport, lport = m.groups()
    try:
        addrinfo = socket.getaddrinfo(host, 0, 0, socket.SOCK_STREAM)
    except socket.gaierror:
        raise Fatal('Unable to resolve address: %s' % host)
    # If the address is a domain with multiple IPs and a mask is also
    # provided, proceed cautiously:
    if cidr is not None:
        addr_v6 = [a for a in addrinfo if a[0] == socket.AF_INET6]
        addr_v4 = [a for a in addrinfo if a[0] == socket.AF_INET]
        # Refuse to proceed if IPv4 and IPv6 addresses are present:
        if len(addr_v6) > 0 and len(addr_v4) > 0:
            raise Fatal("%s has IPv4 and IPv6 addresses, so the mask "
                        "of /%s is not supported. Specify the IP "
                        "addresses directly if you wish to specify "
                        "a mask." % (host, cidr))
        # Warn if a domain has multiple IPs of the same type (IPv4 vs
        # IPv6) and the mask is applied to all of the IPs.
        if len(addr_v4) > 1 or len(addr_v6) > 1:
            print("WARNING: %s has multiple IP addresses. The "
                  "mask of /%s is applied to all of the addresses."
                  % (host, cidr))
    rv = []
    for a in addrinfo:
        family, _, _, _, addr = a
        # Largest possible slash value we can use with this IP:
        max_cidr = 32 if family == socket.AF_INET else 128
        if cidr is None:  # if no mask, use largest mask
            cidr_to_use = max_cidr
        else:   # verify user-provided mask is appropriate
            cidr_to_use = int(cidr)
            if not 0 <= cidr_to_use <= max_cidr:
                raise Fatal('Slash in CIDR notation (/%d) is '
                            'not between 0 and %d'
                            % (cidr_to_use, max_cidr))
        rv.append((family, addr[0], cidr_to_use,
                   int(fport or 0), int(lport or fport or 0)))
    return rv
 # 1.2.3.4:567 or just 1.2.3.4 or just 567
 # [1:2::3]:456 or [1:2::3] or just [::]:567
 # example.com:123 or just example.com
 def parse_ipport(s):
    s = str(s)
    if s.isdigit():
        rx = r'()(\d+)$'
    elif ']' in s:
        rx = r'(?:\[([^]]+)])(?::(\d+))?$'
    else:
        rx = r'([\w\.\-]+)(?::(\d+))?$'
    m = re.match(rx, s)
    if not m:
        raise Fatal('%r is not a valid IP:port format' % s)
    host, port = m.groups()
    host = host or '0.0.0.0'
    port = int(port or 0)
    try:
        addrinfo = socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM)
    except socket.gaierror:
        raise Fatal('Unable to resolve address: %s' % host)
    if len(addrinfo) > 1:
        print("WARNING: Host %s has more than one IP, only using one of them."
              % host)
    family, _, _, _, addr = min(addrinfo)
    # Note: addr contains (ip, port)
    return (family,) + addr[:2]
 def parse_list(lst):
    """Parse a comma separated string into a list."""
    return re.split(r'[\s,]+', lst.strip()) if lst else []
 def parse_namespace(namespace):
    try:
        assert re.fullmatch(
            r'(@?[a-z_A-Z]\w+(?:\.@?[a-z_A-Z]\w+)*)', namespace)
        return namespace
    except AssertionError:
        raise Fatal("%r is not a valid namespace name." % namespace)
 class Concat(Action):
    def __init__(self, option_strings, dest, nargs=None, **kwargs):
        if nargs is not None:
            raise ValueError("nargs not supported")
        super(Concat, self).__init__(option_strings, dest, **kwargs)
    def __call__(self, parser, namespace, values, option_string=None):
        curr_value = getattr(namespace, self.dest, None) or []
        setattr(namespace, self.dest, curr_value + values)
 # Override one function in the ArgumentParser so that we can have
 # better control for how we parse files containing arguments. We
 # expect one argument per line, but strip whitespace/quotes from the
 # beginning/end of the lines.
 class MyArgumentParser(ArgumentParser):
    def convert_arg_line_to_args(self, arg_line):
        # Ignore comments
        if arg_line.startswith("#"):
            return []
        # strip whitespace at beginning and end of line
        arg_line = arg_line.strip()
        # When copying parameters from the command line to a file,
        # some users might copy the quotes they used on the command
        # line into the config file. We ignore these if the line
        # starts and ends with the same quote.
        if arg_line.startswith("'") and arg_line.endswith("'") or \
           arg_line.startswith('"') and arg_line.endswith('"'):
            arg_line = arg_line[1:-1]
        return [arg_line]
 parser = MyArgumentParser(
    prog="sshuttle",
    usage="%(prog)s [-l [ip:]port] -r [user@]sshserver[:port] <subnets...>",
    fromfile_prefix_chars="@"
 )
 parser.add_argument(
    "subnets",
    metavar="IP/MASK[:PORT[-PORT]]...",
    nargs="*",
    type=parse_subnetport,
    help="""
    capture and forward traffic to these subnets (whitespace separated)
    """
 )
 parser.add_argument(
    "-l", "--listen",
    metavar="[IP:]PORT",
    help="""
    transproxy to this ip address and port number
    """
 )
 parser.add_argument(
    "-H", "--auto-hosts",
    action="store_true",
    help="""
    continuously scan for remote hostnames and update local /etc/hosts as
    they are found
    """
 )
 parser.add_argument(
    "-N", "--auto-nets",
    action="store_true",
    help="""
    automatically determine subnets to route
    """
 )
 parser.add_argument(
    "--dns",
    action="store_true",
    help="""
    capture local DNS requests and forward to the remote DNS server
    """
 )
 parser.add_argument(
    "--ns-hosts",
    metavar="IP[,IP]",
    default=[],
    type=parse_list,
    help="""
    capture and forward DNS requests made to the following servers
    (comma separated)
    """
 )
 parser.add_argument(
    "--to-ns",
    metavar="IP[:PORT]",
    type=parse_ipport,
    help="""
    the DNS server to forward requests to; defaults to servers in
    /etc/resolv.conf on remote side if not given.
    """
 )
 if sys.platform == 'win32':
    method_choices = ["auto", "windivert"]
 else:
    method_choices = ["auto", "nft", "nat", "tproxy", "pf", "ipfw"]
 parser.add_argument(
    "--method",
    choices=method_choices,
    metavar="TYPE",
    default="auto",
    help="""
    %(choices)s
    """
 )
 parser.add_argument(
    "--python",
    metavar="PATH",
    help="""
    path to python interpreter on the remote server
    """
 )
 parser.add_argument(
    "-r", "--remote",
    metavar="[USERNAME[:PASSWORD]@]ADDR[:PORT]",
    help="""
    ssh hostname (and optional username and password) of remote %(prog)s server
    """
 )
 parser.add_argument(
    "-x", "--exclude",
    metavar="IP/MASK[:PORT[-PORT]]",
    action="append",
    default=[],
    type=parse_subnetport,
    help="""
    exclude this subnet (can be used more than once)
    """
 )
 parser.add_argument(
    "-X", "--exclude-from",
    metavar="PATH",
    action=Concat,
    dest="exclude",
    type=parse_subnetport_file,
    help="""
    exclude the subnets in a file (whitespace separated)
    """
 )
 parser.add_argument(
    "-v", "--verbose",
    action="count",
    default=0,
    help="""
    increase debug message verbosity (can be used more than once)
    """
 )
 parser.add_argument(
    "-V", "--version",
    action="version",
    version=__version__,
    help="""
    print the %(prog)s version number and exit
    """
 )
 parser.add_argument(
    "-e", "--ssh-cmd",
    metavar="CMD",
    default="ssh",
    help="""
    the command to use to connect to the remote [%(default)s]
    """
 )
 parser.add_argument(
    "--no-cmd-delimiter",
    action="store_false",
    dest="add_cmd_delimiter",
    help="""
    do not add a double dash before the python command
    """
 )
 parser.add_argument(
    "--remote-shell",
    metavar="PROGRAM",
    help="""
    alternate remote shell program instead of defacto posix shell.
    For Windows targets it would be either `cmd` or `powershell` unless something like git-bash is in use.
    """
 )
 parser.add_argument(
    "--seed-hosts",
    metavar="HOSTNAME[,HOSTNAME]",
    default=[],
    help="""
    comma-separated list of hostnames for initial scan (may be used with
    or without --auto-hosts)
    """
 )
 parser.add_argument(
    "--no-latency-control",
    action="store_false",
    dest="latency_control",
    help="""
    sacrifice latency to improve bandwidth benchmarks
    """
 )
 parser.add_argument(
    "--latency-buffer-size",
    metavar="SIZE",
    type=int,
    default=32768,
    dest="latency_buffer_size",
    help="""
    size of latency control buffer
    """
 )
 parser.add_argument(
    "--wrap",
    metavar="NUM",
    type=int,
    help="""
    restart counting channel numbers after this number (for testing)
    """
 )
 parser.add_argument(
    "--disable-ipv6",
    action="store_true",
    help="""
    disable IPv6 support
    """
 )
 parser.add_argument(
    "-D", "--daemon",
    action="store_true",
    help="""
    run in the background as a daemon
    """
 )
 parser.add_argument(
    "-s", "--subnets",
    metavar="PATH",
    action=Concat,
    dest="subnets_file",
    default=[],
    type=parse_subnetport_file,
    help="""
    file where the subnets are stored, instead of on the command line
    """
 )
 parser.add_argument(
    "--syslog",
    action="store_true",
    help="""
    send log messages to syslog (default if you use --daemon)
    """
 )
 parser.add_argument(
    "--pidfile",
    metavar="PATH",
    default="./sshuttle.pid",
    help="""
    pidfile name (only if using --daemon) [%(default)s]
    """
 )
 parser.add_argument(
    "--user",
    help="""
    apply all the rules only to this linux user
    """
 )
 parser.add_argument(
    "--group",
    help="""
    apply all the rules only to this linux group
    """
 )
 parser.add_argument(
    "--firewall",
    action="store_true",
    help="""
    (internal use only)
    """
 )
 parser.add_argument(
    "--hostwatch",
    action="store_true",
    help="""
    (internal use only)
    """
 )
 parser.add_argument(
    "--sudoers-no-modify",
    action="store_true",
    help="""
    Prints a sudo configuration to STDOUT which allows a user to
    run sshuttle without a password. This option is INSECURE because,
    with some cleverness, it also allows the user to run any command
    as root without a password. The output also includes a suggested
    method for you to install the configuration.
    """
 )
 parser.add_argument(
    "--sudoers-user",
    default="",
    help="""
    Set the user name or group with %%group_name for passwordless operation.
    Default is the current user. Only works with the --sudoers-no-modify option.
    """
 )
 parser.add_argument(
    "--no-sudo-pythonpath",
    action="store_false",
    dest="sudo_pythonpath",
    help="""
    do not set PYTHONPATH when invoking sudo
    """
 )
 parser.add_argument(
    "-t", "--tmark",
    metavar="[MARK]",
    default="0x01",
    help="""
    tproxy optional traffic mark with provided MARK value in
    hexadecimal (default '0x01')
    """
 )
 if sys.platform == 'linux':
    net_ns_group = parser.add_mutually_exclusive_group(
        required=False)
    net_ns_group.add_argument(
        '--namespace',
        type=parse_namespace,
        help="Run inside of a net namespace with the given name."
    )
    net_ns_group.add_argument(
        '--namespace-pid',
        type=int,
        help="""
        Run inside the net namespace used by the process with
        the given pid."""
    )
--- a/sshuttle/sdnotify.py
+++ b/sshuttle/sdnotify.py
@ -1,63 +0,0 @@
 """When sshuttle is run via a systemd service file, we can communicate
 to systemd about the status of the sshuttle process. In particular, we
 can send READY status to tell systemd that sshuttle has completed
 startup and send STOPPING to indicate that sshuttle is beginning
 shutdown.
 For details, see:
 https://www.freedesktop.org/software/systemd/man/sd_notify.html
 """
 import socket
 import os
 from sshuttle.helpers import debug1
 def _notify(message):
    """Send a notification message to systemd."""
    addr = os.environ.get("NOTIFY_SOCKET", None)
    if not addr or len(addr) == 1 or addr[0] not in ('/', '@'):
        return False
    addr = '\0' + addr[1:] if addr[0] == '@' else addr
    try:
        sock = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM)
    except (OSError, IOError) as e:
        debug1("Error creating socket to notify systemd: %s" % e)
        return False
    if not message:
        return False
    assert isinstance(message, bytes)
    try:
        return (sock.sendto(message, addr) > 0)
    except (OSError, IOError) as e:
        debug1("Error notifying systemd: %s" % e)
        return False
 def send(*messages):
    """Send multiple messages to systemd."""
    return _notify(b'\n'.join(messages))
 def ready():
    """Constructs a message that is appropriate to send upon completion of
 sshuttle startup."""
    return b"READY=1"
 def stop():
    """Constructs a message that is appropriate to send when sshuttle is
 beginning to shutdown."""
    return b"STOPPING=1"
 def status(message):
    """Constructs a status message to be sent to systemd."""
    return b"STATUS=%s" % message.encode('utf8')
--- a/sshuttle/server.py
+++ b/sshuttle/server.py
@ -1,442 +0,0 @@
 import re
 import struct
 import socket
 import traceback
 import time
 import sys
 import os
 import io
 import sshuttle.ssnet as ssnet
 import sshuttle.helpers as helpers
 import sshuttle.hostwatch as hostwatch
 import subprocess as ssubprocess
 from sshuttle.ssnet import Handler, Proxy, Mux, MuxWrapper
 from sshuttle.helpers import b, log, debug1, debug2, debug3, Fatal, \
    get_random_nameserver, which, get_env, SocketRWShim
 def _ipmatch(ipstr):
    # FIXME: IPv4 only
    if ipstr == 'default':
        ipstr = '0.0.0.0/0'
    m = re.match(r'^(\d+(\.\d+(\.\d+(\.\d+)?)?)?)(?:/(\d+))?$', ipstr)
    if m:
        g = m.groups()
        ips = g[0]
        width = int(g[4] or 32)
        if g[1] is None:
            ips += '.0.0.0'
            width = min(width, 8)
        elif g[2] is None:
            ips += '.0.0'
            width = min(width, 16)
        elif g[3] is None:
            ips += '.0'
            width = min(width, 24)
        return (struct.unpack('!I', socket.inet_aton(ips))[0], width)
 def _ipstr(ip, width):
    # FIXME: IPv4 only
    if width >= 32:
        return ip
    else:
        return "%s/%d" % (ip, width)
 def _maskbits(netmask):
    # FIXME: IPv4 only
    if not netmask:
        return 32
    for i in range(32):
        if netmask[0] & _shl(1, i):
            return 32 - i
    return 0
 def _shl(n, bits):
    return n * int(2 ** bits)
 def _route_netstat(line):
    cols = line.split(None)
    if len(cols) < 3:
        return None, None
    ipw = _ipmatch(cols[0])
    maskw = _ipmatch(cols[2])  # linux only
    mask = _maskbits(maskw)   # returns 32 if maskw is null
    return ipw, mask
 def _route_iproute(line):
    ipm = line.split(None, 1)[0]
    if '/' not in ipm:
        return None, None
    ip, mask = ipm.split('/')
    ipw = _ipmatch(ip)
    return ipw, int(mask)
 def _route_windows(line):
    if " On-link " not in line:
        return None, None
    dest, net_mask = re.split(r'\s+', line.strip())[:2]
    if net_mask == "255.255.255.255":
        return None, None
    for p in ('127.', '0.', '224.', '169.254.'):
        if dest.startswith(p):
            return None, None
    ipw = _ipmatch(dest)
    mask = _maskbits(_ipmatch(net_mask))
    return ipw, mask
 def _list_routes(argv, extract_route):
    # FIXME: IPv4 only
    p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, env=get_env())
    routes = []
    for line in p.stdout:
        if not line.strip():
            continue
        ipw, mask = extract_route(line.decode("ASCII"))
        if not ipw:
            continue
        width = min(ipw[1], mask)
        ip = ipw[0] & _shl(_shl(1, width) - 1, 32 - width)
        routes.append(
            (socket.AF_INET, socket.inet_ntoa(struct.pack('!I', ip)), width))
    rv = p.wait()
    if rv != 0:
        log('WARNING: %r returned %d' % (argv, rv))
    return routes
 def list_routes():
    if sys.platform == 'win32':
        routes = _list_routes(['route', 'PRINT', '-4'], _route_windows)
    else:
        if which('ip'):
            routes = _list_routes(['ip', 'route'], _route_iproute)
        elif which('netstat'):
            routes = _list_routes(['netstat', '-rn'], _route_netstat)
        else:
            log('WARNING: Neither "ip" nor "netstat" were found on the server. '
                '--auto-nets feature will not work.')
            routes = []
    for (family, ip, width) in routes:
        if not ip.startswith('0.') and not ip.startswith('127.'):
            yield (family, ip, width)
 def _exc_dump():
    exc_info = sys.exc_info()
    return ''.join(traceback.format_exception(*exc_info))
 def start_hostwatch(seed_hosts, auto_hosts):
    s1, s2 = socket.socketpair()
    pid = os.fork()
    if not pid:
        # child
        rv = 99
        try:
            try:
                s2.close()
                os.dup2(s1.fileno(), 1)
                os.dup2(s1.fileno(), 0)
                s1.close()
                rv = hostwatch.hw_main(seed_hosts, auto_hosts) or 0
            except Exception:
                log('%s' % _exc_dump())
                rv = 98
        finally:
            os._exit(rv)
    s1.close()
    return pid, s2
 class Hostwatch:
    def __init__(self):
        self.pid = 0
        self.sock = None
 class DnsProxy(Handler):
    def __init__(self, mux, chan, request, to_nameserver):
        Handler.__init__(self, [])
        self.timeout = time.time() + 30
        self.mux = mux
        self.chan = chan
        self.tries = 0
        self.request = request
        self.peers = {}
        self.to_ns_peer = None
        self.to_ns_port = None
        if to_nameserver is None:
            self.to_nameserver = None
        else:
            self.to_ns_peer, self.to_ns_port = to_nameserver.split("@")
            self.to_nameserver = self._addrinfo(self.to_ns_peer,
                                                self.to_ns_port)
        self.try_send()
    @staticmethod
    def _addrinfo(peer, port):
        if int(port) == 0:
            port = 53
        family, _, _, _, sockaddr = socket.getaddrinfo(peer, port)[0]
        return (family, sockaddr)
    def try_send(self):
        if self.tries >= 3:
            return
        self.tries += 1
        if self.to_nameserver is None:
            _, peer = get_random_nameserver()
            port = 53
        else:
            peer = self.to_ns_peer
            port = int(self.to_ns_port)
        family, sockaddr = self._addrinfo(peer, port)
        sock = socket.socket(family, socket.SOCK_DGRAM)
        sock.connect(sockaddr)
        self.peers[sock] = peer
        debug2('DNS: sending to %r:%d (try %d)' % (peer, port, self.tries))
        try:
            sock.send(self.request)
            self.socks.append(sock)
        except socket.error:
            _, e = sys.exc_info()[:2]
            if e.args[0] in ssnet.NET_ERRS:
                # might have been spurious; try again.
                # Note: these errors sometimes are reported by recv(),
                # and sometimes by send().  We have to catch both.
                debug2('DNS send to %r: %s' % (peer, e))
                self.try_send()
                return
            else:
                log('DNS send to %r: %s' % (peer, e))
                return
    def callback(self, sock):
        peer = self.peers[sock]
        try:
            data = sock.recv(4096)
        except socket.error:
            _, e = sys.exc_info()[:2]
            self.socks.remove(sock)
            del self.peers[sock]
            if e.args[0] in ssnet.NET_ERRS:
                # might have been spurious; try again.
                # Note: these errors sometimes are reported by recv(),
                # and sometimes by send().  We have to catch both.
                debug2('DNS recv from %r: %s' % (peer, e))
                self.try_send()
                return
            else:
                log('DNS recv from %r: %s' % (peer, e))
                return
        debug2('DNS response: %d bytes' % len(data))
        self.mux.send(self.chan, ssnet.CMD_DNS_RESPONSE, data)
        self.ok = False
 class UdpProxy(Handler):
    def __init__(self, mux, chan, family):
        sock = socket.socket(family, socket.SOCK_DGRAM)
        Handler.__init__(self, [sock])
        self.timeout = time.time() + 30
        self.mux = mux
        self.chan = chan
        self.sock = sock
    def send(self, dstip, data):
        debug2('UDP: sending to %r port %d' % dstip)
        try:
            self.sock.sendto(data, dstip)
        except socket.error:
            _, e = sys.exc_info()[:2]
            log('UDP send to %r port %d: %s' % (dstip[0], dstip[1], e))
            return
    def callback(self, sock):
        try:
            data, peer = sock.recvfrom(4096)
        except socket.error:
            _, e = sys.exc_info()[:2]
            log('UDP recv from %r port %d: %s' % (peer[0], peer[1], e))
            return
        debug2('UDP response: %d bytes' % len(data))
        hdr = b("%s,%r," % (peer[0], peer[1]))
        self.mux.send(self.chan, ssnet.CMD_UDP_DATA, hdr + data)
 def main(latency_control, latency_buffer_size, auto_hosts, to_nameserver,
         auto_nets):
    try:
        helpers.logprefix = ' s: '
        debug1('latency control setting = %r' % latency_control)
        if latency_buffer_size:
            import sshuttle.ssnet as ssnet
            ssnet.LATENCY_BUFFER_SIZE = latency_buffer_size
        # synchronization header
        sys.stdout.write('\0\0SSHUTTLE0001')
        sys.stdout.flush()
        handlers = []
        # get unbuffered stdin and stdout in binary mode. Equivalent to stdin.buffer/stdout.buffer (Only available in Python 3)
        r, w = io.FileIO(0, mode='r'), io.FileIO(1, mode='w')
        if sys.platform == 'win32':
            def _deferred_exit():
                time.sleep(1)  # give enough time to write logs to stderr
                os._exit(23)
            shim = SocketRWShim(r, w, on_end=_deferred_exit)
            mux = Mux(*shim.makefiles())
        else:
            mux = Mux(r, w)
        handlers.append(mux)
        debug1('auto-nets:' + str(auto_nets))
        if auto_nets:
            routes = list(list_routes())
            debug1('available routes:')
            for r in routes:
                debug1('  %d/%s/%d' % r)
        else:
            routes = []
        routepkt = ''
        for r in routes:
            routepkt += '%d,%s,%d\n' % r
        mux.send(0, ssnet.CMD_ROUTES, b(routepkt))
        hw = Hostwatch()
        hw.leftover = b('')
        def hostwatch_ready(sock):
            assert hw.pid
            content = hw.sock.recv(4096)
            if content:
                lines = (hw.leftover + content).split(b('\n'))
                if lines[-1]:
                    # no terminating newline: entry isn't complete yet!
                    hw.leftover = lines.pop()
                    lines.append(b(''))
                else:
                    hw.leftover = b('')
                mux.send(0, ssnet.CMD_HOST_LIST, b('\n').join(lines))
            else:
                raise Fatal('hostwatch process died')
        def got_host_req(data):
            if not hw.pid:
                (hw.pid, hw.sock) = start_hostwatch(
                        data.decode("ASCII").strip().split(), auto_hosts)
                handlers.append(Handler(socks=[hw.sock],
                                        callback=hostwatch_ready))
        mux.got_host_req = got_host_req
        def new_channel(channel, data):
            (family, dstip, dstport) = data.decode("ASCII").split(',', 2)
            family = int(family)
            # AF_INET is the same constant on Linux and BSD but AF_INET6
            # is different. As the client and server can be running on
            # different platforms we can not just set the socket family
            # to what comes in the wire.
            if family != socket.AF_INET:
                family = socket.AF_INET6
            dstport = int(dstport)
            outwrap = ssnet.connect_dst(family, dstip, dstport)
            handlers.append(Proxy(MuxWrapper(mux, channel), outwrap))
        mux.new_channel = new_channel
        dnshandlers = {}
        def dns_req(channel, data):
            debug2('Incoming DNS request channel=%d.' % channel)
            h = DnsProxy(mux, channel, data, to_nameserver)
            handlers.append(h)
            dnshandlers[channel] = h
        mux.got_dns_req = dns_req
        udphandlers = {}
        def udp_req(channel, cmd, data):
            debug2('Incoming UDP request channel=%d, cmd=%d' %
                   (channel, cmd))
            if cmd == ssnet.CMD_UDP_DATA:
                (dstip, dstport, data) = data.split(b(','), 2)
                dstport = int(dstport)
                debug2('is incoming UDP data. %r %d.' % (dstip, dstport))
                h = udphandlers[channel]
                h.send((dstip, dstport), data)
            elif cmd == ssnet.CMD_UDP_CLOSE:
                debug2('is incoming UDP close')
                h = udphandlers[channel]
                h.ok = False
                del mux.channels[channel]
        def udp_open(channel, data):
            debug2('Incoming UDP open.')
            family = int(data)
            mux.channels[channel] = lambda cmd, data: udp_req(channel, cmd,
                                                              data)
            if channel in udphandlers:
                raise Fatal('UDP connection channel %d already open' %
                            channel)
            else:
                h = UdpProxy(mux, channel, family)
                handlers.append(h)
                udphandlers[channel] = h
        mux.got_udp_open = udp_open
        while mux.ok:
            if hw.pid:
                assert hw.pid > 0
                (rpid, rv) = os.waitpid(hw.pid, os.WNOHANG)
                if rpid:
                    raise Fatal(
                        'hostwatch exited unexpectedly: code 0x%04x' % rv)
            ssnet.runonce(handlers, mux)
            if latency_control:
                mux.check_fullness()
            if dnshandlers:
                now = time.time()
                remove = []
                for channel, h in dnshandlers.items():
                    if h.timeout < now or not h.ok:
                        debug3('expiring dnsreqs channel=%d' % channel)
                        remove.append(channel)
                        h.ok = False
                for channel in remove:
                    del dnshandlers[channel]
            if udphandlers:
                remove = []
                for channel, h in udphandlers.items():
                    if not h.ok:
                        debug3('expiring UDP channel=%d' % channel)
                        remove.append(channel)
                        h.ok = False
                for channel in remove:
                    del udphandlers[channel]
    except Fatal as e:
        log('fatal: %s' % e)
        sys.exit(99)
--- a/sshuttle/ssh.py
+++ b/sshuttle/ssh.py
@ -1,255 +0,0 @@
 import sys
 import os
 import re
 import socket
 import zlib
 import importlib
 import importlib.util
 import subprocess as ssubprocess
 import shlex
 from shlex import quote
 import ipaddress
 from urllib.parse import urlparse
 import sshuttle.helpers as helpers
 from sshuttle.helpers import debug2, which, get_path, SocketRWShim, Fatal
 def get_module_source(name):
    spec = importlib.util.find_spec(name)
    with open(spec.origin, "rt") as f:
        return f.read().encode("utf-8")
 def empackage(z, name, data=None):
    if not data:
        data = get_module_source(name)
    content = z.compress(data)
    content += z.flush(zlib.Z_SYNC_FLUSH)
    return b'%s\n%d\n%s' % (name.encode("ASCII"), len(content), content)
 def parse_hostport(rhostport):
    """
    parses the given rhostport variable, looking like this:
            [username[:password]@]host[:port]
    if only host is given, can be a hostname, IPv4/v6 address or a ssh alias
    from ~/.ssh/config
    and returns a tuple (username, password, port, host)
    """
    # leave use of default port to ssh command to prevent overwriting
    # ports configured in ~/.ssh/config when no port is given
    if rhostport is None or len(rhostport) == 0:
        return None, None, None, None
    port = None
    username = None
    password = None
    host = rhostport
    if "@" in host:
        # split username (and possible password) from the host[:port]
        username, host = host.rsplit("@", 1)
        # Fix #410 bad username error detect
        if ":" in username:
            # this will even allow for the username to be empty
            username, password = username.split(":", 1)
    if ":" in host:
        # IPv6 address and/or got a port specified
        # If it is an IPv6 address with port specification,
        # then it will look like: [::1]:22
        try:
            # try to parse host as an IP address,
            # if that works it is an IPv6 address
            host = str(ipaddress.ip_address(host))
        except ValueError:
            # if that fails parse as URL to get the port
            parsed = urlparse('//{}'.format(host))
            try:
                host = str(ipaddress.ip_address(parsed.hostname))
            except ValueError:
                # else if both fails, we have a hostname with port
                host = parsed.hostname
            port = parsed.port
    if password is None or len(password) == 0:
        password = None
    return username, password, port, host
 def connect(ssh_cmd, rhostport, python, stderr, add_cmd_delimiter, remote_shell, options):
    username, password, port, host = parse_hostport(rhostport)
    if username:
        rhost = "{}@{}".format(username, host)
    else:
        rhost = host
    z = zlib.compressobj(1)
    content = get_module_source('sshuttle.assembler')
    optdata = ''.join("%s=%r\n" % (k, v) for (k, v) in list(options.items()))
    optdata = optdata.encode("UTF8")
    content2 = (empackage(z, 'sshuttle') +
                empackage(z, 'sshuttle.cmdline_options', optdata) +
                empackage(z, 'sshuttle.helpers') +
                empackage(z, 'sshuttle.ssnet') +
                empackage(z, 'sshuttle.hostwatch') +
                empackage(z, 'sshuttle.server') +
                b"\n")
    # If the exec() program calls sys.exit(), it should exit python
    # and the sys.exit(98) call won't be reached (so we try to only
    # exit that way in the server). However, if the code that we
    # exec() simply returns from main, then we will return from
    # exec(). If the server's python process dies, it should stop
    # executing and also won't reach sys.exit(98).
    #
    # So, we shouldn't reach sys.exit(98) and we certainly shouldn't
    # reach it immediately after trying to start the server.
    pyscript = r"""
                import sys, os;
                verbosity=%d;
                stdin = os.fdopen(0, 'rb');
                exec(compile(stdin.read(%d), 'assembler.py', 'exec'));
                sys.exit(98);
                """ % (helpers.verbose or 0, len(content))
    pyscript = re.sub(r'\s+', ' ', pyscript.strip())
    if not rhost:
        # ignore the --python argument when running locally; we already know
        # which python version works.
        argv = [sys.executable, '-c', pyscript]
    else:
        if ssh_cmd:
            sshl = shlex.split(ssh_cmd)
        else:
            sshl = ['ssh']
        if port is not None:
            portl = ["-p", str(port)]
        else:
            portl = []
        if remote_shell == "cmd":
            pycmd = '"%s" -c "%s"' % (python or 'python', pyscript)
        elif remote_shell == "powershell":
            for c in ('\'', ' ', ';', '(', ')', ','):
                pyscript = pyscript.replace(c, '`' + c)
            pycmd = '%s -c %s' % (python or 'python', pyscript)
        else:  # posix shell expected
            if python:
                pycmd = '"%s" -c "%s"' % (python, pyscript)
            else:
                # By default, we run the following code in a shell.
                # However, with restricted shells and other unusual
                # situations, there can be trouble. See the RESTRICTED
                # SHELL section in "man bash" for more information. The
                # code makes many assumptions:
                #
                # (1) That /bin/sh exists and that we can call it.
                # Restricted shells often do *not* allow you to run
                # programs specified with an absolute path like /bin/sh.
                # Either way, if there is trouble with this, it should
                # return error code 127.
                #
                # (2) python3 or python exists in the PATH and is
                # executable. If they aren't, then exec won't work (see (4)
                # below).
                #
                # (3) In /bin/sh, that we can redirect stderr in order to
                # hide the version that "python3 -V" might print (some
                # restricted shells don't allow redirection, see
                # RESTRICTED SHELL section in 'man bash'). However, if we
                # are in a restricted shell, we'd likely have trouble with
                # assumption (1) above.
                #
                # (4) The 'exec' command should work except if we failed
                # to exec python because it doesn't exist or isn't
                # executable OR if exec isn't allowed (some restricted
                # shells don't allow exec). If the exec succeeded, it will
                # not return and not get to the "exit 97" command. If exec
                # does return, we exit with code 97.
                #
                # Specifying the exact python program to run with --python
                # avoids many of the issues above. However, if
                # you have a restricted shell on remote, you may only be
                # able to run python if it is in your PATH (and you can't
                # run programs specified with an absolute path). In that
                # case, sshuttle might not work at all since it is not
                # possible to run python on the remote machine---even if
                # it is present.
                devnull = '/dev/null'
                pycmd = ("P=python3; $P -V 2>%s || P=python; "
                         "exec \"$P\" -c %s; exit 97") % \
                    (devnull, quote(pyscript))
                pycmd = ("/bin/sh -c {}".format(quote(pycmd)))
        if password is not None:
            os.environ['SSHPASS'] = str(password)
            argv = (["sshpass", "-e"] + sshl +
                    portl + [rhost])
        else:
            argv = (sshl + portl + [rhost])
        if add_cmd_delimiter:
            argv += ['--', pycmd]
        else:
            argv += [pycmd]
    # Our which() function searches for programs in get_path()
    # directories (which include PATH). This step isn't strictly
    # necessary if ssh is already in the user's PATH, but it makes the
    # error message friendlier if the user incorrectly passes in a
    # custom ssh command that we cannot find.
    abs_path = which(argv[0])
    if abs_path is None:
        raise Fatal("Failed to find '%s' in path %s" % (argv[0], get_path()))
    argv[0] = abs_path
    if sys.platform != 'win32':
        (s1, s2) = socket.socketpair()
        pstdin, pstdout = os.dup(s1.fileno()), os.dup(s1.fileno())
        def preexec_fn():
            # runs in the child process
            s2.close()
        s1.close()
        def get_server_io():
            os.close(pstdin)
            os.close(pstdout)
            return s2.makefile("rb", buffering=0), s2.makefile("wb", buffering=0)
    else:
        # In Windows CPython, BSD sockets are not supported as subprocess stdio
        # and select.select() used in ssnet.py won't work on Windows pipes.
        # So we have to use both socketpair (for select.select) and pipes (for subprocess.Popen) together
        # along with reader/writer threads to stream data between them
        # NOTE: Their could be a better way. Need to investigate further on this.
        #   Either to use sockets as stdio for subprocess. Or to use pipes but with a select() alternative
        #   https://stackoverflow.com/questions/4993119/redirect-io-of-process-to-windows-socket
        pstdin = ssubprocess.PIPE
        pstdout = ssubprocess.PIPE
        preexec_fn = None
        def get_server_io():
            shim = SocketRWShim(p.stdout, p.stdin, on_end=lambda: p.terminate())
            return shim.makefiles()
    # See: stackoverflow.com/questions/48671215/howto-workaround-of-close-fds-true-and-redirect-stdout-stderr-on-windows
    close_fds = False if sys.platform == 'win32' else True
    debug2("executing: %r" % argv)
    p = ssubprocess.Popen(argv, stdin=pstdin, stdout=pstdout, preexec_fn=preexec_fn,
                          close_fds=close_fds, stderr=stderr, bufsize=0)
    rfile, wfile = get_server_io()
    wfile.write(content)
    wfile.write(content2)
    return p, rfile, wfile
--- a/sshuttle/ssyslog.py
+++ b/sshuttle/ssyslog.py
@ -1,31 +0,0 @@
 import sys
 import os
 import subprocess as ssubprocess
 _p = None
 def start_syslog():
    global _p
    with open(os.devnull, 'w') as devnull:
        _p = ssubprocess.Popen(
            ['logger', '-p', 'daemon.err', '-t', 'sshuttle'],
            stdin=ssubprocess.PIPE,
            stdout=devnull,
            stderr=devnull
        )
 def close_stdin():
    sys.stdin.close()
 def stdout_to_syslog():
    sys.stdout.flush()
    os.dup2(_p.stdin.fileno(), sys.stdout.fileno())
 def stderr_to_syslog():
    sys.stderr.flush()
    os.dup2(_p.stdin.fileno(), sys.stderr.fileno())
--- a/sshuttle/sudoers.py
+++ b/sshuttle/sudoers.py
@ -1,45 +0,0 @@
 import os
 import sys
 import getpass
 from uuid import uuid4
 def build_config(user_name):
    """Generates a sudoers configuration to allow passwordless execution of sshuttle."""
    argv0 = os.path.abspath(sys.argv[0])
    is_python_script = argv0.endswith('.py')
    executable = f"{sys.executable} {argv0}" if is_python_script else argv0
    dist_packages = os.path.dirname(os.path.abspath(__file__))
    cmd_alias = f"SSHUTTLE{uuid4().hex[-3:].upper()}"
    template = f"""
 # WARNING: If you intend to restrict a user to only running the
 # sshuttle command as root, THIS CONFIGURATION IS INSECURE.
 # When a user can run sshuttle as root (with or without a password),
 # they can also run other commands as root because sshuttle itself
 # can run a command specified by the user with the --ssh-cmd option.
 # INSTRUCTIONS: Add this text to your sudo configuration to run
 # sshuttle without needing to enter a sudo password. To use this
 # configuration, run 'visudo /etc/sudoers.d/sshuttle_auto' as root and
 # paste this text into the editor that it opens. If you want to give
 # multiple users these privileges, you may wish to use different
 # filenames for each one (i.e., /etc/sudoers.d/sshuttle_auto_john).
 # This configuration was initially generated by the
 # 'sshuttle --sudoers-no-modify' command.
 Cmnd_Alias {cmd_alias} = /usr/bin/env PYTHONPATH={dist_packages} {executable} *
 {user_name} ALL=NOPASSWD: {cmd_alias}
 """
    return template
 def sudoers(user_name=None):
    user_name = user_name or getpass.getuser()
    content = build_config(user_name)
    sys.stdout.write(content)
    exit(0)
--- a/sshuttle/ssnet.py
+++ b/sshuttle/ssnet.py
@ -1,71 +1,60 @@
-import sys
+import struct, socket, errno, select
-import struct
+if not globals().get('skip_imports'):
-import socket
+    from helpers import *
 import errno
 import select
 import os
 from sshuttle.helpers import b, log, debug1, debug2, debug3, Fatal, set_non_blocking_io
 MAX_CHANNEL = 65535
-LATENCY_BUFFER_SIZE = 32768
+    
-
+# these don't exist in the socket module in python 2.3!
 SHUT_RD = 0
 SHUT_WR = 1
 SHUT_RDWR = 2
 HDR_LEN = 8
 CMD_EXIT = 0x4200
 CMD_PING = 0x4201
 CMD_PONG = 0x4202
-CMD_TCP_CONNECT = 0x4203
+CMD_CONNECT = 0x4203
-CMD_TCP_STOP_SENDING = 0x4204
+CMD_STOP_SENDING = 0x4204
-CMD_TCP_EOF = 0x4205
+CMD_EOF = 0x4205
-CMD_TCP_DATA = 0x4206
+CMD_DATA = 0x4206
 CMD_ROUTES = 0x4207
 CMD_HOST_REQ = 0x4208
 CMD_HOST_LIST = 0x4209
 CMD_DNS_REQ = 0x420a
 CMD_DNS_RESPONSE = 0x420b
 CMD_UDP_OPEN = 0x420c
 CMD_UDP_DATA = 0x420d
 CMD_UDP_CLOSE = 0x420e
 cmd_to_name = {
    CMD_EXIT: 'EXIT',
    CMD_PING: 'PING',
    CMD_PONG: 'PONG',
-    CMD_TCP_CONNECT: 'TCP_CONNECT',
+    CMD_CONNECT: 'CONNECT',
-    CMD_TCP_STOP_SENDING: 'TCP_STOP_SENDING',
+    CMD_STOP_SENDING: 'STOP_SENDING',
-    CMD_TCP_EOF: 'TCP_EOF',
+    CMD_EOF: 'EOF',
-    CMD_TCP_DATA: 'TCP_DATA',
+    CMD_DATA: 'DATA',
    CMD_ROUTES: 'ROUTES',
    CMD_HOST_REQ: 'HOST_REQ',
    CMD_HOST_LIST: 'HOST_LIST',
    CMD_DNS_REQ: 'DNS_REQ',
    CMD_DNS_RESPONSE: 'DNS_RESPONSE',
    CMD_UDP_OPEN: 'UDP_OPEN',
    CMD_UDP_DATA: 'UDP_DATA',
    CMD_UDP_CLOSE: 'UDP_CLOSE',
 }
 NET_ERRS = [errno.ECONNREFUSED, errno.ETIMEDOUT,
            errno.EHOSTUNREACH, errno.ENETUNREACH,
-            errno.EHOSTDOWN, errno.ENETDOWN,
+            errno.EHOSTDOWN, errno.ENETDOWN]
            errno.ENETUNREACH, errno.ECONNABORTED,
            errno.ECONNRESET]
-def _add(socks, elem):
+def _add(l, elem):
-    if elem not in socks:
+    if not elem in l:
-        socks.append(elem)
+        l.append(elem)
-def _fds(socks):
+def _fds(l):
    out = []
-    for i in socks:
+    for i in l:
        try:
            out.append(i.fileno())
        except AttributeError:
@ -77,13 +66,11 @@ def _fds(socks):
 def _nb_clean(func, *args):
    try:
        return func(*args)
-    except (OSError, socket.error):
+    except OSError, e:
        # Note: In python2 socket.error != OSError (In python3, they are same)
        _, e = sys.exc_info()[:2]
        if e.errno not in (errno.EWOULDBLOCK, errno.EAGAIN):
            raise
        else:
-            debug3('%s: err was: %s' % (func.__name__, e))
+            debug3('%s: err was: %s\n' % (func.__name__, e))
            return None
@ -92,26 +79,18 @@ def _try_peername(sock):
        pn = sock.getpeername()
        if pn:
            return '%s:%s' % (pn[0], pn[1])
-    except socket.error:
+    except socket.error, e:
-        _, e = sys.exc_info()[:2]
+        if e.args[0] not in (errno.ENOTCONN, errno.ENOTSOCK):
        if e.args[0] == errno.EINVAL:
            pass
        elif e.args[0] not in (errno.ENOTCONN, errno.ENOTSOCK):
            raise
    except AttributeError:
        pass
    return 'unknown'
 _swcount = 0
 class SockWrapper:
    def __init__(self, rsock, wsock, connect_to=None, peername=None):
        global _swcount
        _swcount += 1
-        debug3('creating new SockWrapper (%d now exist)' % _swcount)
+        debug3('creating new SockWrapper (%d now exist)\n' % _swcount)
        self.exc = None
        self.rsock = rsock
        self.wsock = wsock
@ -124,9 +103,9 @@ class SockWrapper:
    def __del__(self):
        global _swcount
        _swcount -= 1
-        debug1('%r: deleting (%d remain)' % (self, _swcount))
+        debug1('%r: deleting (%d remain)\n' % (self, _swcount))
        if self.exc:
-            debug1('%r: error was: %s' % (self, self.exc))
+            debug1('%r: error was: %s\n' % (self, self.exc))
    def __repr__(self):
        if self.rsock == self.wsock:
@ -148,14 +127,19 @@ class SockWrapper:
        if not self.connect_to:
            return  # already connected
        self.rsock.setblocking(False)
-        debug3('%r: trying connect to %r' % (self, self.connect_to))
+        debug3('%r: trying connect to %r\n' % (self, self.connect_to))
        if socket.inet_aton(self.connect_to[0])[0] == '\0':
            self.seterr(Exception("Can't connect to %r: "
                                  "IP address starts with zero\n"
                                  % (self.connect_to,)))
            self.connect_to = None
            return
        try:
            self.rsock.connect(self.connect_to)
            # connected successfully (Linux)
            self.connect_to = None
-        except socket.error:
+        except socket.error, e:
-            _, e = sys.exc_info()[:2]
+            debug3('%r: connect result: %s\n' % (self, e))
            debug3('%r: connect result: %s' % (self, e))
            if e.args[0] == errno.EINVAL:
                # this is what happens when you call connect() on a socket
                # that is now connected but returned EINPROGRESS last time,
@ -165,28 +149,22 @@ class SockWrapper:
                realerr = self.rsock.getsockopt(socket.SOL_SOCKET,
                                                socket.SO_ERROR)
                e = socket.error(realerr, os.strerror(realerr))
-                debug3('%r: fixed connect result: %s' % (self, e))
+                debug3('%r: fixed connect result: %s\n' % (self, e))
            if e.args[0] in [errno.EINPROGRESS, errno.EALREADY]:
                pass  # not connected yet
            elif sys.platform == 'win32' and e.args[0] == errno.WSAEWOULDBLOCK:  # 10035
                pass  # not connected yet
            elif e.args[0] == 0:
-                if sys.platform == 'win32':
+                # connected successfully (weird Linux bug?)
-                    # On Windows "real" error of EINVAL could be 0, when socket is in connecting state
+                # Sometimes Linux seems to return EINVAL when it isn't
-                    pass
+                # invalid.  This *may* be caused by a race condition
-                else:
+                # between connect() and getsockopt(SO_ERROR) (ie. it
-                    # connected successfully (weird Linux bug?)
+                # finishes connecting in between the two, so there is no
-                    # Sometimes Linux seems to return EINVAL when it isn't
+                # longer an error).  However, I'm not sure of that.
-                    # invalid.  This *may* be caused by a race condition
+                #
-                    # between connect() and getsockopt(SO_ERROR) (ie. it
+                # I did get at least one report that the problem went away
-                    # finishes connecting in between the two, so there is no
+                # when we added this, however.
-                    # longer an error).  However, I'm not sure of that.
+                self.connect_to = None
                    #
                    # I did get at least one report that the problem went away
                    # when we added this, however.
                    self.connect_to = None
            elif e.args[0] == errno.EISCONN:
-                # connected successfully (BSD + Windows)
+                # connected successfully (BSD)
                self.connect_to = None
            elif e.args[0] in NET_ERRS + [errno.EACCES, errno.EPERM]:
                # a "normal" kind of error
@ -197,21 +175,20 @@ class SockWrapper:
    def noread(self):
        if not self.shut_read:
-            debug2('%r: done reading' % self)
+            debug2('%r: done reading\n' % self)
            self.shut_read = True
-
+            #self.rsock.shutdown(SHUT_RD)  # doesn't do anything anyway
    def nowrite(self):
        if not self.shut_write:
-            debug2('%r: done writing' % self)
+            debug2('%r: done writing\n' % self)
            self.shut_write = True
            try:
                self.wsock.shutdown(SHUT_WR)
-            except socket.error:
+            except socket.error, e:
                _, e = sys.exc_info()[:2]
                self.seterr('nowrite: %s' % e)
-    @staticmethod
+    def too_full(self):
    def too_full():
        return False  # fullness is determined by the socket's select() state
    def uwrite(self, buf):
@ -219,20 +196,19 @@ class SockWrapper:
            return 0  # still connecting
        self.wsock.setblocking(False)
        try:
-            return _nb_clean(self.wsock.send, buf)
+            return _nb_clean(os.write, self.wsock.fileno(), buf)
-        except OSError:
+        except OSError, e:
            _, e = sys.exc_info()[:2]
            if e.errno == errno.EPIPE:
-                debug1('%r: uwrite: got EPIPE' % self)
+                debug1('%r: uwrite: got EPIPE\n' % self)
                self.nowrite()
                return 0
            else:
                # unexpected error... stream is dead
                self.seterr('uwrite: %s' % e)
                return 0
-
+        
    def write(self, buf):
-        assert buf
+        assert(buf)
        return self.uwrite(buf)
    def uread(self):
@ -242,11 +218,10 @@ class SockWrapper:
            return
        self.rsock.setblocking(False)
        try:
-            return _nb_clean(self.rsock.recv, 65536)
+            return _nb_clean(os.read, self.rsock.fileno(), 65536)
-        except OSError:
+        except OSError, e:
            _, e = sys.exc_info()[:2]
            self.seterr('uread: %s' % e)
-            return b('')  # unexpected error... we'll call it EOF
+            return '' # unexpected error... we'll call it EOF
    def fill(self):
        if self.buf:
@ -254,7 +229,7 @@ class SockWrapper:
        rb = self.uread()
        if rb:
            self.buf.append(rb)
-        if rb == b(''):  # empty string means EOF; None means temporarily empty
+        if rb == '':  # empty string means EOF; None means temporarily empty
            self.noread()
    def copy_to(self, outwrap):
@ -268,8 +243,7 @@ class SockWrapper:
 class Handler:
-
+    def __init__(self, socks = None, callback = None):
    def __init__(self, socks=None, callback=None):
        self.ok = True
        self.socks = socks or []
        if callback:
@ -279,19 +253,18 @@ class Handler:
        for i in self.socks:
            _add(r, i)
-    def callback(self, sock):
+    def callback(self):
-        log('--no callback defined-- %r' % self)
+        log('--no callback defined-- %r\n' % self)
-        (r, _, _) = select.select(self.socks, [], [], 0)
+        (r,w,x) = select.select(self.socks, [], [], 0)
        for s in r:
            v = s.recv(4096)
            if not v:
-                log('--closed-- %r' % self)
+                log('--closed-- %r\n' % self)
                self.socks = []
                self.ok = False
 class Proxy(Handler):
    def __init__(self, wrap1, wrap2):
        Handler.__init__(self, [wrap1.rsock, wrap1.wsock,
                                wrap2.rsock, wrap2.wsock])
@ -299,11 +272,9 @@ class Proxy(Handler):
        self.wrap2 = wrap2
    def pre_select(self, r, w, x):
-        if self.wrap1.shut_write:
+        if self.wrap1.shut_write: self.wrap2.noread()
-            self.wrap2.noread()
+        if self.wrap2.shut_write: self.wrap1.noread()
-        if self.wrap2.shut_write:
+        
            self.wrap1.noread()
        if self.wrap1.connect_to:
            _add(w, self.wrap1.rsock)
        elif self.wrap1.buf:
@ -320,7 +291,7 @@ class Proxy(Handler):
        elif not self.wrap2.shut_read:
            _add(r, self.wrap2.rsock)
-    def callback(self, sock):
+    def callback(self):
        self.wrap1.try_connect()
        self.wrap2.try_connect()
        self.wrap1.fill()
@ -334,33 +305,31 @@ class Proxy(Handler):
            self.wrap2.buf = []
            self.wrap2.noread()
        if (self.wrap1.shut_read and self.wrap2.shut_read and
-                not self.wrap1.buf and not self.wrap2.buf):
+            not self.wrap1.buf and not self.wrap2.buf):
            self.ok = False
            self.wrap1.nowrite()
            self.wrap2.nowrite()
 class Mux(Handler):
-
+    def __init__(self, rsock, wsock):
-    def __init__(self, rfile, wfile):
+        Handler.__init__(self, [rsock, wsock])
-        Handler.__init__(self, [rfile, wfile])
+        self.rsock = rsock
-        self.rfile = rfile
+        self.wsock = wsock
        self.wfile = wfile
        self.new_channel = self.got_dns_req = self.got_routes = None
        self.got_udp_open = self.got_udp_data = self.got_udp_close = None
        self.got_host_req = self.got_host_list = None
        self.channels = {}
        self.chani = 0
        self.want = 0
-        self.inbuf = b('')
+        self.inbuf = ''
        self.outbuf = []
        self.fullness = 0
        self.too_full = False
-        self.send(0, CMD_PING, b('chicken'))
+        self.send(0, CMD_PING, 'chicken')
    def next_channel(self):
        # channel 0 is special, so we never allocate it
-        for _ in range(1024):
+        for timeout in xrange(1024):
            self.chani += 1
            if self.chani > MAX_CHANNEL:
                self.chani = 1
@ -369,52 +338,50 @@ class Mux(Handler):
    def amount_queued(self):
        total = 0
-        for byte in self.outbuf:
+        for b in self.outbuf:
-            total += len(byte)
+            total += len(b)
        return total
-
+            
    def check_fullness(self):
-        if self.fullness > LATENCY_BUFFER_SIZE:
+        if self.fullness > 32768:
            if not self.too_full:
-                self.send(0, CMD_PING, b('rttest'))
+                self.send(0, CMD_PING, 'rttest')
            self.too_full = True
-
+        #ob = []
        #for b in self.outbuf:
        #    (s1,s2,c) = struct.unpack('!ccH', b[:4])
        #    ob.append(c)
        #log('outbuf: %d %r\n' % (self.amount_queued(), ob))
    def send(self, channel, cmd, data):
-        assert isinstance(data, bytes)
+        data = str(data)
-        assert len(data) <= 65535
+        assert(len(data) <= 65535)
-        p = struct.pack('!ccHHH', b('S'), b('S'), channel, cmd, len(data)) \
+        p = struct.pack('!ccHHH', 'S', 'S', channel, cmd, len(data)) + data
            + data
        self.outbuf.append(p)
-        debug2(' > channel=%d cmd=%s len=%d (fullness=%d)'
+        debug2(' > channel=%d cmd=%s len=%d (fullness=%d)\n'
-               % (channel, cmd_to_name.get(cmd, hex(cmd)),
+               % (channel, cmd_to_name.get(cmd,hex(cmd)),
                  len(data), self.fullness))
        # debug3('>>> data: %r' % data)
        self.fullness += len(data)
    def got_packet(self, channel, cmd, data):
-        debug2('<  channel=%d cmd=%s len=%d'
+        debug2('<  channel=%d cmd=%s len=%d\n' 
-               % (channel, cmd_to_name.get(cmd, hex(cmd)), len(data)))
+               % (channel, cmd_to_name.get(cmd,hex(cmd)), len(data)))
        # debug3('<<< data: %r' % data)
        if cmd == CMD_PING:
            self.send(0, CMD_PONG, data)
        elif cmd == CMD_PONG:
-            debug2('received PING response')
+            debug2('received PING response\n')
            self.too_full = False
            self.fullness = 0
        elif cmd == CMD_EXIT:
            self.ok = False
-        elif cmd == CMD_TCP_CONNECT:
+        elif cmd == CMD_CONNECT:
-            assert not self.channels.get(channel)
+            assert(not self.channels.get(channel))
            if self.new_channel:
                self.new_channel(channel, data)
        elif cmd == CMD_DNS_REQ:
-            assert not self.channels.get(channel)
+            assert(not self.channels.get(channel))
            if self.got_dns_req:
                self.got_dns_req(channel, data)
        elif cmd == CMD_UDP_OPEN:
            assert not self.channels.get(channel)
            if self.got_udp_open:
                self.got_udp_open(channel, data)
        elif cmd == CMD_ROUTES:
            if self.got_routes:
                self.got_routes(data)
@ -433,46 +400,43 @@ class Mux(Handler):
        else:
            callback = self.channels.get(channel)
            if not callback:
-                log('warning: closed channel %d got cmd=%s len=%d'
+                log('warning: closed channel %d got cmd=%s len=%d\n' 
-                    % (channel, cmd_to_name.get(cmd, hex(cmd)), len(data)))
+                       % (channel, cmd_to_name.get(cmd,hex(cmd)), len(data)))
            else:
                callback(cmd, data)
    def flush(self):
-        set_non_blocking_io(self.wfile.fileno())
+        self.wsock.setblocking(False)
        if self.outbuf and self.outbuf[0]:
-            wrote = _nb_clean(self.wfile.write, self.outbuf[0])
+            wrote = _nb_clean(os.write, self.wsock.fileno(), self.outbuf[0])
-            # self.wfile.flush()
+            debug2('mux wrote: %r/%d\n' % (wrote, len(self.outbuf[0])))
            debug2('mux wrote: %r/%d' % (wrote, len(self.outbuf[0])))
            if wrote:
                self.outbuf[0] = self.outbuf[0][wrote:]
        while self.outbuf and not self.outbuf[0]:
            self.outbuf[0:1] = []
    def fill(self):
-        set_non_blocking_io(self.rfile.fileno())
+        self.rsock.setblocking(False)
        try:
-            # If LATENCY_BUFFER_SIZE is inappropriately large, we will
+            b = _nb_clean(os.read, self.rsock.fileno(), 32768)
-            # get a MemoryError here. Read no more than 1MiB.
+        except OSError, e:
            read = _nb_clean(self.rfile.read, min(1048576, LATENCY_BUFFER_SIZE))
            debug2('mux read: %r' % len(read))
        except OSError:
            _, e = sys.exc_info()[:2]
            raise Fatal('other end: %r' % e)
-        # log('<<< %r' % b)
+        #log('<<< %r\n' % b)
-        if read == b(''):  # EOF
+        if b == '': # EOF
            self.ok = False
-        if read:
+        if b:
-            self.inbuf += read
+            self.inbuf += b
    def handle(self):
        self.fill()
        #log('inbuf is: (%d,%d) %r\n'
        #     % (self.want, len(self.inbuf), self.inbuf))
        while 1:
            if len(self.inbuf) >= (self.want or HDR_LEN):
-                (s1, s2, channel, cmd, datalen) = \
+                (s1,s2,channel,cmd,datalen) = \
                    struct.unpack('!ccHHH', self.inbuf[:HDR_LEN])
-                assert s1 == b('S')
+                assert(s1 == 'S')
-                assert s2 == b('S')
+                assert(s2 == 'S')
                self.want = datalen + HDR_LEN
            if self.want and len(self.inbuf) >= self.want:
                data = self.inbuf[HDR_LEN:self.want]
@ -483,60 +447,48 @@ class Mux(Handler):
                break
    def pre_select(self, r, w, x):
-        _add(r, self.rfile)
+        _add(r, self.rsock)
        if self.outbuf:
-            _add(w, self.wfile)
+            _add(w, self.wsock)
-    def callback(self, sock):
+    def callback(self):
-        (r, w, _) = select.select([self.rfile], [self.wfile], [], 0)
+        (r,w,x) = select.select([self.rsock], [self.wsock], [], 0)
-        if self.rfile in r:
+        if self.rsock in r:
            self.handle()
-        if self.outbuf and self.wfile in w:
+        if self.outbuf and self.wsock in w:
            self.flush()
 class MuxWrapper(SockWrapper):
    def __init__(self, mux, channel):
-        SockWrapper.__init__(self, mux.rfile, mux.wfile)
+        SockWrapper.__init__(self, mux.rsock, mux.wsock)
        self.mux = mux
        self.channel = channel
        self.mux.channels[channel] = self.got_packet
        self.socks = []
-        debug2('new channel: %d' % channel)
+        debug2('new channel: %d\n' % channel)
    def __del__(self):
        self.nowrite()
        SockWrapper.__del__(self)
    def __repr__(self):
-        return 'SW%r:Mux#%d' % (self.peername, self.channel)
+        return 'SW%r:Mux#%d' % (self.peername,self.channel)
    def noread(self):
        if not self.shut_read:
            self.mux.send(self.channel, CMD_TCP_STOP_SENDING, b(''))
            self.setnoread()
    def setnoread(self):
        if not self.shut_read:
            debug2('%r: done reading' % self)
            self.shut_read = True
            self.mux.send(self.channel, CMD_STOP_SENDING, '')
            self.maybe_close()
    def nowrite(self):
        if not self.shut_write:
            self.mux.send(self.channel, CMD_TCP_EOF, b(''))
            self.setnowrite()
    def setnowrite(self):
        if not self.shut_write:
            debug2('%r: done writing' % self)
            self.shut_write = True
            self.mux.send(self.channel, CMD_EOF, '')
            self.maybe_close()
    def maybe_close(self):
        if self.shut_read and self.shut_write:
            debug2('%r: closing connection' % self)
            # remove the mux's reference to us.  The python garbage collector
            # will then be able to reap our object.
            self.mux.channels[self.channel] = None
@ -549,61 +501,59 @@ class MuxWrapper(SockWrapper):
            return 0  # too much already enqueued
        if len(buf) > 2048:
            buf = buf[:2048]
-        self.mux.send(self.channel, CMD_TCP_DATA, buf)
+        self.mux.send(self.channel, CMD_DATA, buf)
        return len(buf)
    def uread(self):
        if self.shut_read:
-            return b('')  # EOF
+            return '' # EOF
        else:
            return None  # no data available right now
    def got_packet(self, cmd, data):
-        if cmd == CMD_TCP_EOF:
+        if cmd == CMD_EOF:
-            # Remote side already knows the status - set flag but don't notify
+            self.noread()
-            self.setnoread()
+        elif cmd == CMD_STOP_SENDING:
-        elif cmd == CMD_TCP_STOP_SENDING:
+            self.nowrite()
-            # Remote side already knows the status - set flag but don't notify
+        elif cmd == CMD_DATA:
            self.setnowrite()
        elif cmd == CMD_TCP_DATA:
            self.buf.append(data)
        else:
-            raise Exception('unknown command %d (%d bytes)'
+            raise Exception('unknown command %d (%d bytes)' 
                            % (cmd, len(data)))
-def connect_dst(family, ip, port):
+def connect_dst(ip, port):
-    debug2('Connecting to %s:%d' % (ip, port))
+    debug2('Connecting to %s:%d\n' % (ip, port))
-    outsock = socket.socket(family)
+    outsock = socket.socket()
-
+    outsock.setsockopt(socket.SOL_IP, socket.IP_TTL, 42)
    return SockWrapper(outsock, outsock,
-                       connect_to=(ip, port),
+                       connect_to = (ip,port),
-                       peername='%s:%d' % (ip, port))
+                       peername = '%s:%d' % (ip,port))
 def runonce(handlers, mux):
    r = []
    w = []
    x = []
-    to_remove = [s for s in handlers if not s.ok]
+    to_remove = filter(lambda s: not s.ok, handlers)
    for h in to_remove:
        handlers.remove(h)
    for s in handlers:
-        s.pre_select(r, w, x)
+        s.pre_select(r,w,x)
-    debug2('Waiting: %d r=%r w=%r x=%r (fullness=%d/%d)'
+    debug2('Waiting: %d r=%r w=%r x=%r (fullness=%d/%d)\n' 
-           % (len(handlers), _fds(r), _fds(w), _fds(x),
+            % (len(handlers), _fds(r), _fds(w), _fds(x),
               mux.fullness, mux.too_full))
-    (r, w, x) = select.select(r, w, x)
+    (r,w,x) = select.select(r,w,x)
-    debug2('  Ready: %d r=%r w=%r x=%r'
+    debug2('  Ready: %d r=%r w=%r x=%r\n' 
-           % (len(handlers), _fds(r), _fds(w), _fds(x)))
+        % (len(handlers), _fds(r), _fds(w), _fds(x)))
-    ready = r + w + x
+    ready = r+w+x
    did = {}
    for h in handlers:
        for s in h.socks:
            if s in ready:
-                h.callback(s)
+                h.callback()
                did[s] = 1
    for s in ready:
-        if s not in did:
+        if not s in did:
            raise Fatal('socket %r was not used by any handler' % s)
--- a/ssyslog.py
+++ b/ssyslog.py
@ -0,0 +1,16 @@
 import sys, os
 from compat import ssubprocess
 _p = None
 def start_syslog():
    global _p
    _p = ssubprocess.Popen(['logger',
                            '-p', 'daemon.notice',
                            '-t', 'sshuttle'], stdin=ssubprocess.PIPE)
 def stderr_to_syslog():
    sys.stdout.flush()
    sys.stderr.flush()
    os.dup2(_p.stdin.fileno(), 2)
--- a/stresstest.py
+++ b/stresstest.py
@ -0,0 +1,86 @@
 #!/usr/bin/env python
 import sys, os, socket, select, struct, time
 listener = socket.socket()
 listener.bind(('127.0.0.1', 0))
 listener.listen(500)
 servers = []
 clients = []
 remain = {}
 NUMCLIENTS = 50
 count = 0
 while 1:
    if len(clients) < NUMCLIENTS:
        c = socket.socket()
        c.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        c.bind(('0.0.0.0', 0))
        c.connect(listener.getsockname())
        count += 1
        if count >= 16384:
            count = 1
        print 'cli CREATING %d' % count
        b = struct.pack('I', count) + 'x'*count
        remain[c] = count
        print 'cli  >> %r' % len(b)
        c.send(b)
        c.shutdown(socket.SHUT_WR)
        clients.append(c)
        r = [listener]
        time.sleep(0.1)
    else:
        r = [listener]+servers+clients
    print 'select(%d)' % len(r)
    r,w,x = select.select(r, [], [], 5)
    assert(r)
    for i in r:
        if i == listener:
            s,addr = listener.accept()
            servers.append(s)
        elif i in servers:
            b = i.recv(4096)
            print 'srv <<  %r' % len(b)
            if not i in remain:
                assert(len(b) >= 4)
                want = struct.unpack('I', b[:4])[0]
                b = b[4:]
                #i.send('y'*want)
            else:
                want = remain[i]
            if want < len(b):
                print 'weird wanted %d bytes, got %d: %r' % (want, len(b), b)
                assert(want >= len(b))
            want -= len(b)
            remain[i] = want
            if not b:  # EOF
                if want:
                    print 'weird: eof but wanted %d more' % want
                    assert(want == 0)
                i.close()
                servers.remove(i)
                del remain[i]
            else:
                print 'srv  >> %r' % len(b)
                i.send('y'*len(b))
                if not want:
                    i.shutdown(socket.SHUT_WR)
        elif i in clients:
            b = i.recv(4096)
            print 'cli <<  %r' % len(b)
            want = remain[i]
            if want < len(b):
                print 'weird wanted %d bytes, got %d: %r' % (want, len(b), b)
                assert(want >= len(b))
            want -= len(b)
            remain[i] = want
            if not b:  # EOF
                if want:
                    print 'weird: eof but wanted %d more' % want
                    assert(want == 0)
                i.close()
                clients.remove(i)
                del remain[i]
 listener.accept()
--- a/tests/client/test_firewall.py
+++ b/tests/client/test_firewall.py
@ -1,163 +0,0 @@
 import io
 import os
 from socket import AF_INET, AF_INET6
 from unittest.mock import Mock, patch, call
 import pytest
 import sshuttle.firewall
 def setup_daemon():
    stdin = io.BytesIO(u"""ROUTES
 {inet},24,0,1.2.3.0,8000,9000
 {inet},32,1,1.2.3.66,8080,8080
 {inet6},64,0,2404:6800:4004:80c::,0,0
 {inet6},128,1,2404:6800:4004:80c::101f,80,80
 NSLIST
 {inet},1.2.3.33
 {inet6},2404:6800:4004:80c::33
 PORTS 1024,1025,1026,1027
 GO 1 - - 0x01 12345
 HOST 1.2.3.3,existing
 """.format(inet=AF_INET, inet6=AF_INET6).encode('ASCII'))
    stdout = Mock()
    return stdin, stdout
 def test_rewrite_etc_hosts(tmpdir):
    orig_hosts = tmpdir.join("hosts.orig")
    orig_hosts.write("1.2.3.3 existing\n")
    new_hosts = tmpdir.join("hosts")
    orig_hosts.copy(new_hosts)
    hostmap = {
        'myhost': '1.2.3.4',
        'myotherhost': '1.2.3.5',
    }
    with patch('sshuttle.firewall.HOSTSFILE', new=str(new_hosts)):
        sshuttle.firewall.rewrite_etc_hosts(hostmap, 10)
    with new_hosts.open() as f:
        line = f.readline()
        s = line.split()
        assert s == ['1.2.3.3', 'existing']
        line = f.readline()
        s = line.split()
        assert s == ['1.2.3.4', 'myhost',
                     '#', 'sshuttle-firewall-10', 'AUTOCREATED']
        line = f.readline()
        s = line.split()
        assert s == ['1.2.3.5', 'myotherhost',
                     '#', 'sshuttle-firewall-10', 'AUTOCREATED']
        line = f.readline()
        assert line == ""
    with patch('sshuttle.firewall.HOSTSFILE', new=str(new_hosts)):
        sshuttle.firewall.restore_etc_hosts(hostmap, 10)
    assert orig_hosts.computehash() == new_hosts.computehash()
@patch('os.link')
@patch('os.rename')
 def test_rewrite_etc_hosts_no_overwrite(mock_link, mock_rename, tmpdir):
    mock_link.side_effect = OSError
    mock_rename.side_effect = OSError
    with pytest.raises(OSError):
        os.link('/test_from', '/test_to')
    with pytest.raises(OSError):
        os.rename('/test_from', '/test_to')
    test_rewrite_etc_hosts(tmpdir)
 def test_subnet_weight():
    subnets = [
        (AF_INET, 16, 0, '192.168.0.0', 0, 0),
        (AF_INET, 24, 0, '192.168.69.0', 0, 0),
        (AF_INET, 32, 0, '192.168.69.70', 0, 0),
        (AF_INET, 32, 1, '192.168.69.70', 0, 0),
        (AF_INET, 32, 1, '192.168.69.70', 80, 80),
        (AF_INET, 0, 1, '0.0.0.0', 0, 0),
        (AF_INET, 0, 1, '0.0.0.0', 8000, 9000),
        (AF_INET, 0, 1, '0.0.0.0', 8000, 8500),
        (AF_INET, 0, 1, '0.0.0.0', 8000, 8000),
        (AF_INET, 0, 1, '0.0.0.0', 400, 450)
    ]
    subnets_sorted = [
        (AF_INET, 32, 1, '192.168.69.70', 80, 80),
        (AF_INET, 0, 1, '0.0.0.0', 8000, 8000),
        (AF_INET, 0, 1, '0.0.0.0', 400, 450),
        (AF_INET, 0, 1, '0.0.0.0', 8000, 8500),
        (AF_INET, 0, 1, '0.0.0.0', 8000, 9000),
        (AF_INET, 32, 1, '192.168.69.70', 0, 0),
        (AF_INET, 32, 0, '192.168.69.70', 0, 0),
        (AF_INET, 24, 0, '192.168.69.0', 0, 0),
        (AF_INET, 16, 0, '192.168.0.0', 0, 0),
        (AF_INET, 0, 1, '0.0.0.0', 0, 0)
    ]
    assert subnets_sorted == sorted(subnets,
                                    key=sshuttle.firewall.subnet_weight,
                                    reverse=True)
@patch('sshuttle.firewall.rewrite_etc_hosts')
@patch('sshuttle.firewall.setup_daemon')
@patch('sshuttle.firewall.get_method')
 def test_main(mock_get_method, mock_setup_daemon, mock_rewrite_etc_hosts):
    stdin, stdout = setup_daemon()
    mock_setup_daemon.return_value = stdin, stdout
    mock_get_method("not_auto").name = "test"
    mock_get_method.reset_mock()
    sshuttle.firewall.main("not_auto", False)
    assert mock_rewrite_etc_hosts.mock_calls == [
        call({'1.2.3.3': 'existing'}, 1024),
        call({}, 1024),
    ]
    assert stdout.mock_calls == [
        call.write(b'READY test\n'),
        call.flush(),
        call.write(b'STARTED\n'),
        call.flush()
    ]
    assert mock_setup_daemon.mock_calls == [call()]
    assert mock_get_method.mock_calls == [
        call('not_auto'),
        call().is_supported(),
        call().is_supported().__bool__(),
        call().setup_firewall(
            1024, 1026,
            [(AF_INET6, u'2404:6800:4004:80c::33')],
            AF_INET6,
            [(AF_INET6, 64, False, u'2404:6800:4004:80c::', 0, 0),
             (AF_INET6, 128, True, u'2404:6800:4004:80c::101f', 80, 80)],
            True,
            None,
            None,
            '0x01'),
        call().setup_firewall(
            1025, 1027,
            [(AF_INET, u'1.2.3.33')],
            AF_INET,
            [(AF_INET, 24, False, u'1.2.3.0', 8000, 9000),
             (AF_INET, 32, True, u'1.2.3.66', 8080, 8080)],
            True,
            None,
            None,
            '0x01'),
        call().wait_for_firewall_ready(12345),
        call().restore_firewall(1024, AF_INET6, True, None, None),
        call().restore_firewall(1025, AF_INET, True, None, None),
    ]
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Tianyi Cui	29d2e06bf5	Added --exclude-from feature. (Slightly modified by apenwarr)	2012-07-06 15:13:30 -04:00
Miguel Landaeta	bff1610050	Document missing --dns option in sshuttle manpage	2012-07-06 15:06:07 -04:00
Avery Pennarun	cce6a9d96d	firewall.py: catch SIGINT and SIGTERM too. There were still a few conditions under some OSes that would cause firewall.py to terminate without cleaning up the firewall settings. 'pkill sshuttle' was one of them. Ignore a couple more signals to further ensure a correct cleanup. (This only affects sshuttle --firewall, which is a subprocess of the main sshuttle process. The firewall is supposed to exit automatically whenever the client exits, and so far that part seems to work reliably.)	2012-07-06 15:00:28 -04:00
Avery Pennarun	5743f29ed6	server.py: slightly rearrange previous commit. Add some documentation about the int() vs long() and the reason behind _shl(). Instead of "from __future__ import generators", just don't use generators.	2012-07-06 15:00:28 -04:00
Saul	42bc6d62db	Two small changes to server.py that allow it to run on python2.2	2012-04-19 23:00:29 -07:00
Avery Pennarun	274ee854d4	clean.do: don't forget to do version/clean.	2012-02-07 12:17:56 -05:00
David Held	12f6a52ec6	Fix runpython.do for systems with unxpected configurations. If the expected arch directory doesn't exist, give up and don't specify arch at all. Currently it expands to '*' which fails. [slightly modified by apenwarr]	2012-02-07 12:16:31 -05:00
Avery Pennarun	e737f4b944	firewall.py: add comments about sysctl problems.	2012-01-08 19:13:39 -05:00
Avery Pennarun	d9f761a8a3	ui-macos: tell the user that we need to reboot on MacOS Lion.	2012-01-08 19:01:18 -05:00
Avery Pennarun	bd20841782	firewall.py: clean up repeated calls to ssubprocess.call(). And make sshuttle exit with a well-defined exit code (111) if it needs to reboot.	2012-01-08 19:01:18 -05:00
Avery Pennarun	4c1a505e37	firewall.py: workaround MacOS 10.7 Lion bug. On top of the bug that already existed in 10.6, Lion also makes the sysctl needed to fix the problem into a read-only variable, so we have to actually change it at kernel boot time and force people to reboot. Nice job, Apple.	2012-01-08 19:01:18 -05:00
Avery Pennarun	41d1f73dc2	Add a --version (-V) option. Now that we imported the feature from redo, might as well use it.	2012-01-06 13:45:43 -05:00
Avery Pennarun	cbc32ff8d8	Import the non-pandoc manpage generator from redo. This makes it easier (possible?) to generate sshuttle.8 from sshuttle.md on MacOS. We also import the git-enhanced version numbering magic so the generated manpage can have a real version number.	2012-01-06 13:35:12 -05:00
Jimmy Tang	6698992f4f	Use the new arguments from redo v0.10. (apenwarr: also updates to the matching, latest minimal/do)	2012-01-06 13:24:56 -05:00
Avery Pennarun	e2c682084c	firewall: catch SIGHUP and SIGPIPE. Not sure if this will fix anything, but it might stop the problem reported on some MacOS versions where the firewall doesn't get cleaned up correctly.	2012-01-06 13:14:55 -05:00
Avery Pennarun	89e914e9d1	ui-macos/main.py: fix wait() to avoid deadlock. If the subprocess was trying to write to its stdout/stderr, its process would never actually finish because it was blocked waiting for us to read it, but we were blocked on waitpid(). Instead, use waitpid(WNOHANG) and continually read from the subprocess (which should be a blocking operation) until it exits.	2012-01-02 18:46:30 -05:00
Avery Pennarun	2268e76771	ipfw: don't use 'log' parameter. I guess we were causing the kernel to syslog on every single packet on MacOS. Oops.	2012-01-02 18:19:19 -05:00
		`@ -0,0 +1 @@`
							`rm -f ~ .~ .8 t/.8 md-to-man .tmp t/.tmp`
		`@ -0,0 +1,2 @@`
							`redo-ifchange md-to-man $2.md.tmp`
							`. ./md-to-man $1 $2 $3`
		`@ -0,0 +1,2 @@`
							`redo ui-macos/clean Documentation/clean version/clean`
							`rm -f ~ /~ .~ /.~ .8 .tmp /.tmp .pyc /*.pyc`