Release version 0.78.0

This reverts commit 7ea2d973c7.

.travis.yml

@@ -1,6 +1,8 @@
 language: python
 python:
+- 2.6
 - 2.7
+- 3.4
 - 3.5
 - pypy
 

CHANGES.rst

@@ -1,3 +1,20 @@
+Release 0.78.0 (Apr 8, 2016)
+============================
+
+* 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.
+
+
+Release 0.77.2 (Mar 7, 2016)
+============================
+
+* Accidentally switched LGPL2 license with GPL2 license in 0.77.1 - now fixed.
+
+
 Release 0.77.1 (Mar 7, 2016)
 ============================
 

LICENSE

@@ -1,22 +1,25 @@
-                    GNU GENERAL PUBLIC LICENSE
+                  GNU LIBRARY GENERAL PUBLIC LICENSE
                        Version 2, June 1991
 
- Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ Copyright (C) 1991 Free Software Foundation, Inc.
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+ 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
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+[This is the first released version of the library GPL.  It is
+ numbered 2 because it goes with version 2 of the ordinary GPL.]
+
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+of all derivatives of our free software and of promoting the sharing
+and reuse of software generally.
 
                             NO WARRANTY
 
-  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+  15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
-FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
-OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
-PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT WARRANTY OF ANY
-OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
-MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE
-PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+LIBRARY IS WITH YOU.  SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME
-REPAIR OR CORRECTION.
+THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
 
-  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+  16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
-WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
-REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU
-INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
-OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
-TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
-YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
-PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
-POSSIBILITY OF SUCH DAMAGES.
+SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGES.
 
                      END OF TERMS AND CONDITIONS
+
+           How to Apply These Terms to Your New Libraries
 
-            How to Apply These Terms to Your New Programs
+  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
+everyone can redistribute and change.  You can do so by permitting
+redistribution under these terms (or, alternatively, under the terms of the
+ordinary General Public License).
 
-  If you develop a new program, and you want it to be of the greatest
+  To apply these terms, attach the following notices to the library.  It is
-possible use to the public, the best way to achieve this is to make it
+safest to attach them to the start of each source file to most effectively
-free software which everyone can redistribute and change under these terms.
+convey the exclusion of warranty; and each file should have at least the
+"copyright" line and a pointer to where the full notice is found.
 
-  To do so, attach the following notices to the program.  It is safest
+    <one line to give the library's name and a brief idea of what it does.>
-to attach them to the start of each source file to most effectively
-convey the exclusion of warranty; and each file should have at least
-the "copyright" line and a pointer to where the full notice is found.
-
-    <one line to give the program's name and a brief idea of what it does.>
     Copyright (C) <year>  <name of author>
 
-    This program is free software; you can redistribute it and/or modify
+    This library is free software; you can redistribute it and/or
-    it under the terms of the GNU General Public License as published by
+    modify it under the terms of the GNU Library General Public
-    the Free Software Foundation; either version 2 of the License, or
+    License as published by the Free Software Foundation; either
-    (at your option) any later version.
+    version 2 of the License, or (at your option) any later version.
 
-    This program is distributed in the hope that it will be useful,
+    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
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-    GNU General Public License for more details.
+    Library General Public License for more details.
 
-    You should have received a copy of the GNU General Public License along
+    You should have received a copy of the GNU Library General Public
-    with this program; if not, write to the Free Software Foundation, Inc.,
+    License along with this library; if not, write to the Free Software
-    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 
 Also add information on how to contact you by electronic and paper mail.
 
-If the program is interactive, make it output a short notice like this
-when it starts in an interactive mode:
-
-    Gnomovision version 69, Copyright (C) year name of author
-    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
-    This is free software, and you are welcome to redistribute it
-    under certain conditions; type `show c' for details.
-
-The hypothetical commands `show w' and `show c' should show the appropriate
-parts of the General Public License.  Of course, the commands you use may
-be called something other than `show w' and `show c'; they could even be
-mouse-clicks or menu items--whatever suits your program.
-
 You should also get your employer (if you work as a programmer) or your
-school, if any, to sign a "copyright disclaimer" for the program, if
+school, if any, to sign a "copyright disclaimer" for the library, if
 necessary.  Here is a sample; alter the names:
 
-  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
-  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+  library `Frob' (a library for tweaking knobs) written by James Random Hacker.
 
-  <signature of Ty Coon>, 1 April 1989
+  <signature of Ty Coon>, 1 April 1990
   Ty Coon, President of Vice
 
-This General Public License does not permit incorporating your program into
+That's all there is to it!
-proprietary programs.  If your program is a subroutine library, you may
-consider it more useful to permit linking proprietary applications with the
-library.  If this is what you want to do, use the GNU Lesser General
-Public License instead of this License.

conftest.py

@@ -0,0 +1,10 @@
+import sys
+
+if sys.version_info >= (3, 0):
+    good_python = sys.version_info >= (3, 5)
+else:
+    good_python = sys.version_info >= (2, 7)
+
+collect_ignore = []
+if not good_python:
+    collect_ignore.append("sshuttle/tests/client")

docs/requirements.rst

@@ -62,6 +62,7 @@ cmd.exe with Administrator access. See :doc:`windows` for more information.
 
 Server side Requirements
 ------------------------
+Server requirements are more relaxed, however it is recommended that you use
 Python 2.7 or Python 3.5.
 
 

run

@@ -1,6 +1,8 @@
 #!/bin/sh
 if python3.5 -V 2>/dev/null; then
 	exec python3.5 -m "sshuttle" "$@"
+elif python2.7 -V 2>/dev/null; then
+    exec python2.7 -m "sshuttle" "$@"
 else
 	exec python -m "sshuttle" "$@"
 fi

sshuttle/__init__.py

@@ -0,0 +1,4 @@
+try:
+    from sshuttle.version import version as __version__
+except ImportError:
+    __version__ = "unknown"

sshuttle/assembler.py

@@ -4,19 +4,20 @@ import imp
 
 z = zlib.decompressobj()
 while 1:
-    name = stdin.readline().strip()
+    name = sys.stdin.readline().strip()
     if name:
         name = name.decode("ASCII")
 
-        nbytes = int(stdin.readline())
+        nbytes = int(sys.stdin.readline())
         if verbosity >= 2:
             sys.stderr.write('server: assembling %r (%d bytes)\n'
                              % (name, nbytes))
-        content = z.decompress(stdin.read(nbytes))
+        content = z.decompress(sys.stdin.read(nbytes))
 
         module = imp.new_module(name)
-        parent, _, parent_name = name.rpartition(".")
+        parents = name.rsplit(".", 1)
-        if parent != "":
+        if len(parents) == 2:
+            parent, parent_name = parents
             setattr(sys.modules[parent], parent_name, module)
 
         code = compile(content, name, "exec")

sshuttle/client.py

@@ -547,11 +547,15 @@ def main(listenip_v6, listenip_v4,
         else:
             listenip_v6 = None
 
-    required.ipv6 = len(subnets_v6) > 0 or len(nslist_v6) > 0 \
+    required.ipv6 = len(subnets_v6) > 0 or listenip_v6 is not None
-        or listenip_v6 is not None
     required.udp = avail.udp
     required.dns = len(nslist) > 0
 
+    # if IPv6 not supported, ignore IPv6 DNS servers
+    if not required.ipv6:
+        nslist_v6 = []
+        nslist = nslist_v4
+
     fw.method.assert_features(required)
 
     if required.ipv6 and listenip_v6 is None:

sshuttle/cmdline.py

@@ -1,199 +1,47 @@
-import sys
 import re
-import socket
 import sshuttle.helpers as helpers
-import sshuttle.options as options
 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_ipport6, parse_ipport4
 from sshuttle.helpers import family_ip_tuple, log, Fatal
 
 
-# 1.2.3.4/5 or just 1.2.3.4
-def parse_subnet4(s):
-    m = re.match(r'(\d+)(?:\.(\d+)\.(\d+)\.(\d+))?(?:/(\d+))?$', s)
-    if not m:
-        raise Fatal('%r is not a valid IP subnet format' % s)
-    (a, b, c, d, width) = m.groups()
-    (a, b, c, d) = (int(a or 0), int(b or 0), int(c or 0), int(d or 0))
-    if width is None:
-        width = 32
-    else:
-        width = int(width)
-    if a > 255 or b > 255 or c > 255 or d > 255:
-        raise Fatal('%d.%d.%d.%d has numbers > 255' % (a, b, c, d))
-    if width > 32:
-        raise Fatal('*/%d is greater than the maximum of 32' % width)
-    return(socket.AF_INET, '%d.%d.%d.%d' % (a, b, c, d), width)
-
-
-# 1:2::3/64 or just 1:2::3
-def parse_subnet6(s):
-    m = re.match(r'(?:([a-fA-F\d:]+))?(?:/(\d+))?$', s)
-    if not m:
-        raise Fatal('%r is not a valid IP subnet format' % s)
-    (net, width) = m.groups()
-    if width is None:
-        width = 128
-    else:
-        width = int(width)
-    if width > 128:
-        raise Fatal('*/%d is greater than the maximum of 128' % width)
-    return(socket.AF_INET6, net, width)
-
-
-# Subnet file, supporting empty lines and hash-started comment lines
-def parse_subnet_file(s):
-    try:
-        handle = open(s, 'r')
-    except OSError:
-        raise Fatal('Unable to open subnet file: %s' % s)
-
-    raw_config_lines = handle.readlines()
-    config_lines = []
-    for line_no, line in enumerate(raw_config_lines):
-        line = line.strip()
-        if len(line) == 0:
-            continue
-        if line[0] == '#':
-            continue
-        config_lines.append(line)
-
-    return config_lines
-
-
-# list of:
-# 1.2.3.4/5 or just 1.2.3.4
-# 1:2::3/64 or just 1:2::3
-def parse_subnets(subnets_str):
-    subnets = []
-    for s in subnets_str:
-        if ':' in s:
-            subnet = parse_subnet6(s)
-        else:
-            subnet = parse_subnet4(s)
-        subnets.append(subnet)
-    return subnets
-
-
-# 1.2.3.4:567 or just 1.2.3.4 or just 567
-def parse_ipport4(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 is None:
-        a = b = c = d = 0
-    return ('%d.%d.%d.%d' % (a, b, c, d), port)
-
-
-# [1:2::3]:456 or [1:2::3] or 456
-def parse_ipport6(s):
-    s = str(s)
-    m = re.match(r'(?:\[([^]]*)])?(?::)?(?:(\d+))?$', s)
-    if not m:
-        raise Fatal('%s is not a valid IP:port format' % s)
-    (ip, port) = m.groups()
-    (ip, port) = (ip or '::', int(port or 0))
-    return (ip, port)
-
-
-def parse_list(list):
-    return re.split(r'[\s,]+', list.strip()) if list else []
-
-
-optspec = """
-sshuttle [-l [ip:]port] [-r [username@]sshserver[:port]] <subnets...>
-sshuttle --firewall <port> <subnets...>
-sshuttle --hostwatch
---
-l,listen=  transproxy to this ip address and port number
-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
-ns-hosts=  capture and forward remote DNS requests to the following servers
-method=    auto, nat, tproxy or pf
-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)
-X,exclude-from=  exclude the subnets in a file (whitespace separated)
-v,verbose  increase debug message verbosity
-V,version  print the sshuttle version number and exit
-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)
-disable-ipv6 disables ipv6 support
-D,daemon   run in the background as a daemon
-s,subnets= file where the subnets are stored, instead of on the command line
-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)
-"""
-
-
 def main():
-    o = options.Options(optspec)
+    opt = parser.parse_args()
-    (opt, flags, extra) = o.parse(sys.argv[1:])
 
-    if opt.version:
-        from sshuttle.version import version
-        print(version)
-        return 0
     if opt.daemon:
         opt.syslog = 1
     if opt.wrap:
         import sshuttle.ssnet as ssnet
-        ssnet.MAX_CHANNEL = int(opt.wrap)
+        ssnet.MAX_CHANNEL = opt.wrap
-    helpers.verbose = opt.verbose or 0
+    helpers.verbose = opt.verbose
 
     try:
         if opt.firewall:
-            if len(extra) != 0:
+            if opt.subnets:
-                o.fatal('exactly zero arguments expected')
+                parser.error('exactly zero arguments expected')
             return firewall.main(opt.method, opt.syslog)
         elif opt.hostwatch:
-            return hostwatch.hw_main(extra)
+            return hostwatch.hw_main(opt.subnets)
         else:
-            if len(extra) < 1 and not opt.auto_nets and not opt.subnets:
+            includes = opt.subnets
-                o.fatal('at least one subnet, subnet file, or -N expected')
+            excludes = opt.exclude
-            includes = extra
+            if not includes and not opt.auto_nets:
-            excludes = ['127.0.0.0/8']
+                parser.error('at least one subnet, subnet file, or -N expected')
-            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
-            nslist = [family_ip_tuple(ns) for ns in parse_list(opt.ns_hosts)]
+            nslist = [family_ip_tuple(ns) for ns in opt.ns_hosts]
             if opt.seed_hosts and not opt.auto_hosts:
-                o.fatal('--seed-hosts only works if you also use -H')
+                parser.error('--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
-            if opt.subnets:
-                includes = parse_subnet_file(opt.subnets)
-            if not opt.method:
-                method_name = "auto"
-            elif opt.method in ["auto", "nat", "tproxy", "pf"]:
-                method_name = opt.method
-            else:
-                o.fatal("method_name %s not supported" % opt.method)
             if opt.listen:
                 ipport_v6 = None
                 ipport_v4 = None
@@ -218,11 +66,11 @@ def main():
                                       opt.latency_control,
                                       opt.dns,
                                       nslist,
-                                      method_name,
+                                      opt.method,
                                       sh,
                                       opt.auto_nets,
-                                      parse_subnets(includes),
+                                      includes,
-                                      parse_subnets(excludes),
+                                      excludes,
                                       opt.daemon, opt.pidfile)
 
             if return_code == 0:

sshuttle/helpers.py

@@ -5,6 +5,16 @@ import errno
 logprefix = ''
 verbose = 0
 
+if sys.version_info[0] == 3:
+    binary_type = bytes
+
+    def b(s):
+        return s.encode("ASCII")
+else:
+    binary_type = str
+
+    def b(s):
+        return s
 
 def log(s):
     global logprefix
@@ -70,7 +80,8 @@ def islocal(ip, family):
     try:
         try:
             sock.bind((ip, 0))
-        except socket.error as e:
+        except socket.error:
+            _, e = sys.exc_info()[:2]
             if e.args[0] == errno.EADDRNOTAVAIL:
                 return False  # not a local IP
             else:

sshuttle/hostwatch.py

@@ -22,7 +22,8 @@ hostnames = {}
 queue = {}
 try:
     null = open('/dev/null', 'wb')
-except IOError as e:
+except IOError:
+    _, e = sys.exc_info()[:2]
     log('warning: %s\n' % e)
     null = os.popen("sh -c 'while read x; do :; done'", 'wb', 4096)
 
@@ -38,7 +39,7 @@ def write_host_cache():
         for name, ip in sorted(hostnames.items()):
             f.write(('%s,%s\n' % (name, ip)).encode("ASCII"))
         f.close()
-        os.chmod(tmpname, 0o600)
+        os.chmod(tmpname, 384) # 600 in octal, 'rw-------'
         os.rename(tmpname, CACHEFILE)
     finally:
         try:
@@ -50,7 +51,8 @@ def write_host_cache():
 def read_host_cache():
     try:
         f = open(CACHEFILE)
-    except IOError as e:
+    except IOError:
+        _, e = sys.exc_info()[:2]
         if e.errno == errno.ENOENT:
             return
         else:
@@ -124,7 +126,8 @@ def _check_netstat():
         p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, stderr=null)
         content = p.stdout.read().decode("ASCII")
         p.wait()
-    except OSError as e:
+    except OSError:
+        _, e = sys.exc_info()[:2]
         log('%r failed: %r\n' % (argv, e))
         return
 
@@ -144,7 +147,8 @@ def _check_smb(hostname):
         p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, stderr=null)
         lines = p.stdout.readlines()
         p.wait()
-    except OSError as e:
+    except OSError:
+        _, e = sys.exc_info()[:2]
         log('%r failed: %r\n' % (argv, e))
         _smb_ok = False
         return
@@ -201,7 +205,8 @@ def _check_nmb(hostname, is_workgroup, is_master):
         p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, stderr=null)
         lines = p.stdout.readlines()
         rv = p.wait()
-    except OSError as e:
+    except OSError:
+        _, e = sys.exc_info()[:2]
         log('%r failed: %r\n' % (argv, e))
         _nmb_ok = False
         return

sshuttle/options.py

@@ -1,215 +1,306 @@
-"""Command-line options parser.
-With the help of an options spec string, easily parse command-line options.
-"""
-import sys
-import os
-import textwrap
-import getopt
 import re
-import struct
+import socket
+from argparse import ArgumentParser, Action, ArgumentTypeError as Fatal
+from sshuttle import __version__
 
 
-class OptDict:
+# 1.2.3.4/5 or just 1.2.3.4
-
+def parse_subnet4(s):
-    def __init__(self):
+    m = re.match(r'(\d+)(?:\.(\d+)\.(\d+)\.(\d+))?(?:/(\d+))?$', s)
-        self._opts = {}
+    if not m:
-
+        raise Fatal('%r is not a valid IP subnet format' % s)
-    def __setitem__(self, k, v):
+    (a, b, c, d, width) = m.groups()
-        if k.startswith('no-') or k.startswith('no_'):
+    (a, b, c, d) = (int(a or 0), int(b or 0), int(c or 0), int(d or 0))
-            k = k[3:]
+    if width is None:
-            v = not v
+        width = 32
-        self._opts[k] = v
+    else:
-
+        width = int(width)
-    def __getitem__(self, k):
+    if a > 255 or b > 255 or c > 255 or d > 255:
-        if k.startswith('no-') or k.startswith('no_'):
+        raise Fatal('%d.%d.%d.%d has numbers > 255' % (a, b, c, d))
-            return not self._opts[k[3:]]
+    if width > 32:
-        return self._opts[k]
+        raise Fatal('*/%d is greater than the maximum of 32' % width)
-
+    return(socket.AF_INET, '%d.%d.%d.%d' % (a, b, c, d), width)
-    def __getattr__(self, k):
-        return self[k]
 
 
-def _default_onabort(msg):
+# 1:2::3/64 or just 1:2::3
-    sys.exit(97)
+def parse_subnet6(s):
+    m = re.match(r'(?:([a-fA-F\d:]+))?(?:/(\d+))?$', s)
+    if not m:
+        raise Fatal('%r is not a valid IP subnet format' % s)
+    (net, width) = m.groups()
+    if width is None:
+        width = 128
+    else:
+        width = int(width)
+    if width > 128:
+        raise Fatal('*/%d is greater than the maximum of 128' % width)
+    return(socket.AF_INET6, net, width)
 
 
-def _intify(v):
+# Subnet file, supporting empty lines and hash-started comment lines
+def parse_subnet_file(s):
     try:
-        vv = int(v or '')
+        handle = open(s, 'r')
-        if str(vv) == v:
+    except OSError:
-            return vv
+        raise Fatal('Unable to open subnet file: %s' % s)
-    except ValueError:
+
-        pass
+    raw_config_lines = handle.readlines()
-    return v
+    subnets = []
+    for line_no, line in enumerate(raw_config_lines):
+        line = line.strip()
+        if len(line) == 0:
+            continue
+        if line[0] == '#':
+            continue
+        subnets.append(parse_subnet(line))
+
+    return subnets
 
 
-def _atoi(v):
+# 1.2.3.4/5 or just 1.2.3.4
-    try:
+# 1:2::3/64 or just 1:2::3
-        return int(v or 0)
+def parse_subnet(subnet_str):
-    except ValueError:
+    if ':' in subnet_str:
-        return 0
+        return parse_subnet6(subnet_str)
+    else:
+        return parse_subnet4(subnet_str)
 
 
-def _remove_negative_kv(k, v):
+# 1.2.3.4:567 or just 1.2.3.4 or just 567
-    if k.startswith('no-') or k.startswith('no_'):
+def parse_ipport4(s):
-        return k[3:], not v
+    s = str(s)
-    return k, v
+    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 is None:
+        a = b = c = d = 0
+    return ('%d.%d.%d.%d' % (a, b, c, d), port)
 
 
-def _remove_negative_k(k):
+# [1:2::3]:456 or [1:2::3] or 456
-    return _remove_negative_kv(k, None)[0]
+def parse_ipport6(s):
+    s = str(s)
+    m = re.match(r'(?:\[([^]]*)])?(?::)?(?:(\d+))?$', s)
+    if not m:
+        raise Fatal('%s is not a valid IP:port format' % s)
+    (ip, port) = m.groups()
+    (ip, port) = (ip or '::', int(port or 0))
+    return (ip, port)
 
 
-def _tty_width():
+def parse_list(list):
-    if not hasattr(sys.stderr, "fileno"):
+    return re.split(r'[\s,]+', list.strip()) if list else []
-        return _atoi(os.environ.get('WIDTH')) or 70
-    s = struct.pack("HHHH", 0, 0, 0, 0)
-    try:
-        import fcntl
-        import 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:
+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)
 
-    """Option parser.
+    def __call__(self, parser, namespace, values, option_string=None):
-    When constructed, two strings are mandatory. The first one is the command
+        curr_value = getattr(namespace, self.dest, [])
-    name showed before error messages. The second one is a string called an
+        setattr(namespace, self.dest, curr_value + values)
-    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
+parser = ArgumentParser(
-    behaviour is to exit the program.
+    prog="sshuttle",
+    usage="%(prog)s [-l [ip:]port] [-r [user@]sshserver[:port]] <subnets...>"
+)
+parser.add_argument(
+    "subnets",
+    metavar="IP/MASK [IP/MASK...]",
+    nargs="*",
+    type=parse_subnet,
+    help="""
+    capture and forward traffic to these subnets (whitespace separated)
     """
-
+)
-    def __init__(self, optspec, optfunc=getopt.gnu_getopt,
+parser.add_argument(
-                 onabort=_default_onabort):
+    "-l", "--listen",
-        self.optspec = optspec
+    metavar="[IP:]PORT",
-        self._onabort = onabort
+    help="""
-        self.optfunc = optfunc
+    transproxy to this ip address and port number
-        self._aliases = {}
+    """
-        self._shortopts = 'h?'
+)
-        self._longopts = ['help']
+parser.add_argument(
-        self._hasparms = {}
+    "-H", "--auto-hosts",
-        self._defaults = {}
+    action="store_true",
-        self._usagestr = self._gen_usage()
+    help="""
-
+    scan for remote hostnames and update local /etc/hosts
-    def _gen_usage(self):
+    """
-        out = []
+)
-        lines = self.optspec.strip().split('\n')
+parser.add_argument(
-        lines.reverse()
+    "-N", "--auto-nets",
-        first_syn = True
+    action="store_true",
-        while lines:
+    help="""
-            l = lines.pop()
+    automatically determine subnets to route
-            if l == '--':
+    """
-                break
+)
-            out.append('%s: %s\n' % (first_syn and 'usage' or '   or', l))
+parser.add_argument(
-            first_syn = False
+    "--dns",
-        out.append('\n')
+    action="store_true",
-        last_was_option = False
+    help="""
-        while lines:
+    capture local DNS requests and forward to the remote DNS server
-            l = lines.pop()
+    """
-            if l.startswith(' '):
+)
-                out.append('%s%s\n' % (last_was_option and '\n' or '',
+parser.add_argument(
-                                       l.lstrip()))
+    "--ns-hosts",
-                last_was_option = False
+    metavar="IP[,IP]",
-            elif l:
+    default=[],
-                (flags, extra) = l.split(' ', 1)
+    type=parse_list,
-                extra = extra.strip()
+    help="""
-                if flags.endswith('='):
+    capture and forward DNS requests made to the following servers
-                    flags = flags[:-1]
+    """
-                    has_parm = 1
+)
-                else:
+parser.add_argument(
-                    has_parm = 0
+    "--method",
-                g = re.search(r'\[([^\]]*)\]$', extra)
+    choices=["auto", "nat", "tproxy", "pf"],
-                if g:
+    metavar="TYPE",
-                    defval = g.group(1)
+    default="auto",
-                else:
+    help="""
-                    defval = None
+    %(choices)s
-                flagl = flags.split(',')
+    """
-                flagl_nice = []
+)
-                for _f in flagl:
+parser.add_argument(
-                    f, dvi = _remove_negative_kv(_f, _intify(defval))
+    "--python",
-                    self._aliases[f] = _remove_negative_k(flagl[0])
+    metavar="PATH",
-                    self._hasparms[f] = has_parm
+    help="""
-                    self._defaults[f] = dvi
+    path to python interpreter on the remote server
-                    if len(f) == 1:
+    """
-                        self._shortopts += f + (has_parm and ':' or '')
+)
-                        flagl_nice.append('-' + f)
+parser.add_argument(
-                    else:
+    "-r", "--remote",
-                        f_nice = re.sub(r'\W', '_', f)
+    metavar="[USERNAME@]ADDR[:PORT]",
-                        self._aliases[f_nice] = _remove_negative_k(flagl[0])
+    help="""
-                        self._longopts.append(f + (has_parm and '=' or ''))
+    ssh hostname (and optional username) of remote %(prog)s server
-                        self._longopts.append('no-' + f)
+    """
-                        flagl_nice.append('--' + _f)
+)
-                flags_nice = ', '.join(flagl_nice)
+parser.add_argument(
-                if has_parm:
+    "-x", "--exclude",
-                    flags_nice += ' ...'
+    metavar="IP/MASK",
-                prefix = '    %-20s  ' % flags_nice
+    action="append",
-                argtext = '\n'.join(textwrap.wrap(extra, width=_tty_width(),
+    default=[parse_subnet('127.0.0.1/8')],
-                                                  initial_indent=prefix,
+    type=parse_subnet,
-                                                  subsequent_indent=' ' * 28))
+    help="""
-                out.append(argtext + '\n')
+    exclude this subnet (can be used more than once)
-                last_was_option = True
+    """
-            else:
+)
-                out.append('\n')
+parser.add_argument(
-                last_was_option = False
+    "-X", "--exclude-from",
-        return ''.join(out).rstrip() + '\n'
+    metavar="PATH",
-
+    action=Concat,
-    def usage(self, msg=""):
+    dest="exclude",
-        """Print usage string to stderr and abort."""
+    type=parse_subnet_file,
-        sys.stderr.write(self._usagestr)
+    help="""
-        e = self._onabort and self._onabort(msg) or None
+    exclude the subnets in a file (whitespace separated)
-        if e:
+    """
-            raise e
+)
-
+parser.add_argument(
-    def fatal(self, s):
+    "-v", "--verbose",
-        """Print an error message to stderr and abort with usage string."""
+    action="count",
-        msg = 'error: %s\n' % s
+    default=0,
-        sys.stderr.write(msg)
+    help="""
-        return self.usage(msg)
+    increase debug message verbosity
-
+    """
-    def parse(self, args):
+)
-        """Parse a list of arguments and return (options, flags, extra).
+parser.add_argument(
-
+    "-V", "--version",
-        In the returned tuple, "options" is an OptDict with known options,
+    action="version",
-        "flags" is a list of option flags that were used on the command-line,
+    version=__version__,
-        and "extra" is a list of positional arguments.
+    help="""
-        """
+    print the %(prog)s version number and exit
-        try:
+    """
-            (flags, extra) = self.optfunc(
+)
-                args, self._shortopts, self._longopts)
+parser.add_argument(
-        except getopt.GetoptError as e:
+    "-e", "--ssh-cmd",
-            self.fatal(e)
+    metavar="CMD",
-
+    default="ssh",
-        opt = OptDict()
+    help="""
-
+    the command to use to connect to the remote [%(default)s]
-        for k, v in self._defaults.items():
+    """
-            k = self._aliases[k]
+)
-            opt[k] = v
+parser.add_argument(
-
+    "--seed-hosts",
-        for (k, v) in flags:
+    metavar="HOSTNAME[,HOSTNAME]",
-            k = k.lstrip('-')
+    default=[],
-            if k in ('h', '?', 'help'):
+    help="""
-                self.usage()
+    with -H, use these hostnames for initial scan (comma-separated)
-            if k.startswith('no-'):
+    """
-                k = self._aliases[k[3:]]
+)
-                v = 0
+parser.add_argument(
-            else:
+    "--no-latency-control",
-                k = self._aliases[k]
+    action="store_false",
-                if not self._hasparms[k]:
+    dest="latency_control",
-                    assert(v == '')
+    help="""
-                    v = (opt._opts.get(k) or 0) + 1
+    sacrifice latency to improve bandwidth benchmarks
-                else:
+    """
-                    v = _intify(v)
+)
-            opt[k] = v
+parser.add_argument(
-        for (f1, f2) in self._aliases.items():
+    "--wrap",
-            opt[f1] = opt._opts.get(f2)
+    metavar="NUM",
-        return (opt, flags, extra)
+    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",
+    type=parse_subnet_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(
+    "--firewall",
+    action="store_true",
+    help="""
+    (internal use only)
+    """
+)
+parser.add_argument(
+    "--hostwatch",
+    action="store_true",
+    help="""
+    (internal use only)
+    """
+)

sshuttle/server.py

@@ -12,32 +12,34 @@ 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 log, debug1, debug2, debug3, Fatal, \
+from sshuttle.helpers import b, log, debug1, debug2, debug3, Fatal, \
     resolvconf_random_nameserver
 
 
 def _ipmatch(ipstr):
-    if ipstr == b'default':
+    # FIXME: IPv4 only
-        ipstr = b'0.0.0.0/0'
+    if ipstr == 'default':
-    m = re.match(b'^(\d+(\.\d+(\.\d+(\.\d+)?)?)?)(?:/(\d+))?$', ipstr)
+        ipstr = '0.0.0.0/0'
+    m = re.match('^(\d+(\.\d+(\.\d+(\.\d+)?)?)?)(?:/(\d+))?$', ipstr)
     if m:
         g = m.groups()
         ips = g[0]
         width = int(g[4] or 32)
         if g[1] is None:
-            ips += b'.0.0.0'
+            ips += '.0.0.0'
             width = min(width, 8)
         elif g[2] is None:
-            ips += b'.0.0'
+            ips += '.0.0'
             width = min(width, 16)
         elif g[3] is None:
-            ips += b'.0'
+            ips += '.0'
             width = min(width, 24)
-        ips = ips.decode("ASCII")
+        ips = ips
         return (struct.unpack('!I', socket.inet_aton(ips))[0], width)
 
 
 def _ipstr(ip, width):
+    # FIXME: IPv4 only
     if width >= 32:
         return ip
     else:
@@ -45,6 +47,7 @@ def _ipstr(ip, width):
 
 
 def _maskbits(netmask):
+    # FIXME: IPv4 only
     if not netmask:
         return 32
     for i in range(32):
@@ -63,7 +66,7 @@ def _list_routes():
     p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE)
     routes = []
     for line in p.stdout:
-        cols = re.split(b'\s+', line)
+        cols = re.split(r'\s+', line.decode("ASCII"))
         ipw = _ipmatch(cols[0])
         if not ipw:
             continue  # some lines won't be parseable; never mind
@@ -149,7 +152,8 @@ class DnsProxy(Handler):
         try:
             sock.send(self.request)
             self.socks.append(sock)
-        except socket.error as e:
+        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(),
@@ -166,7 +170,8 @@ class DnsProxy(Handler):
 
         try:
             data = sock.recv(4096)
-        except socket.error as e:
+        except socket.error:
+            _, e = sys.exc_info()[:2]
             self.socks.remove(sock)
             del self.peers[sock]
 
@@ -201,14 +206,16 @@ class UdpProxy(Handler):
         debug2('UDP: sending to %r port %d\n' % dstip)
         try:
             self.sock.sendto(data, dstip)
-        except socket.error as e:
+        except socket.error:
+            _, e = sys.exc_info()[:2]
             log('UDP send to %r port %d: %s\n' % (dstip[0], dstip[1], e))
             return
 
     def callback(self, sock):
         try:
             data, peer = sock.recvfrom(4096)
-        except socket.error as e:
+        except socket.error:
+            _, e = sys.exc_info()[:2]
             log('UDP recv from %r port %d: %s\n' % (peer[0], peer[1], e))
             return
         debug2('UDP response: %d bytes\n' % len(data))
@@ -241,26 +248,26 @@ def main(latency_control):
               socket.fromfd(sys.stdout.fileno(),
                             socket.AF_INET, socket.SOCK_STREAM))
     handlers.append(mux)
-    routepkt = b''
+    routepkt = ''
     for r in routes:
-        routepkt += b'%d,%s,%d\n' % (r[0], r[1].encode("ASCII"), r[2])
+        routepkt += '%d,%s,%d\n' % r
-    mux.send(0, ssnet.CMD_ROUTES, routepkt)
+    mux.send(0, ssnet.CMD_ROUTES, b(routepkt))
 
     hw = Hostwatch()
-    hw.leftover = b''
+    hw.leftover = b('')
 
     def hostwatch_ready(sock):
         assert(hw.pid)
         content = hw.sock.recv(4096)
         if content:
-            lines = (hw.leftover + content).split(b'\n')
+            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'')
+                lines.append(b(''))
             else:
-                hw.leftover = b''
+                hw.leftover = b('')
-            mux.send(0, ssnet.CMD_HOST_LIST, b'\n'.join(lines))
+            mux.send(0, ssnet.CMD_HOST_LIST, b('\n').join(lines))
         else:
             raise Fatal('hostwatch process died')
 
@@ -272,7 +279,7 @@ def main(latency_control):
     mux.got_host_req = got_host_req
 
     def new_channel(channel, data):
-        (family, dstip, dstport) = data.split(b',', 2)
+        (family, dstip, dstport) = data.decode("ASCII").split(',', 2)
         family = int(family)
         dstport = int(dstport)
         outwrap = ssnet.connect_dst(family, dstip, dstport)

sshuttle/ssh.py

@@ -8,6 +8,12 @@ import subprocess as ssubprocess
 import sshuttle.helpers as helpers
 from sshuttle.helpers import debug2
 
+try:
+    # Python >= 3.5
+    from shlex import quote
+except ImportError:
+    # Python 2.x
+    from pipes import quote
 
 def readfile(name):
     tokens = name.split(".")
@@ -89,10 +95,10 @@ def connect(ssh_cmd, rhostport, python, stderr, options):
                 b"\n")
 
     pyscript = r"""
-                import sys;
+                import sys, os;
                 verbosity=%d;
-                stdin=getattr(sys.stdin,"buffer",sys.stdin);
+                sys.stdin = os.fdopen(0, "rb");
-                exec(compile(stdin.read(%d), "assembler.py", "exec"))
+                exec(compile(sys.stdin.read(%d), "assembler.py", "exec"))
                 """ % (helpers.verbose or 0, len(content))
     pyscript = re.sub(r'\s+', ' ', pyscript.strip())
 
@@ -109,7 +115,8 @@ def connect(ssh_cmd, rhostport, python, stderr, options):
             pycmd = "'%s' -c '%s'" % (python, pyscript)
         else:
             pycmd = ("P=python3.5; $P -V 2>/dev/null || P=python; "
-                     "exec \"$P\" -c '%s'") % pyscript
+                     "exec \"$P\" -c %s") % quote(pyscript)
+            pycmd = ("exec /bin/sh -c %s" % quote(pycmd))
         argv = (sshl +
                 portl +
                 [rhost, '--', pycmd])

sshuttle/ssnet.py

@@ -1,9 +1,10 @@
+import sys
 import struct
 import socket
 import errno
 import select
 import os
-from sshuttle.helpers import log, debug1, debug2, debug3, Fatal
+from sshuttle.helpers import b, binary_type, log, debug1, debug2, debug3, Fatal
 
 MAX_CHANNEL = 65535
 
@@ -75,7 +76,8 @@ def _fds(l):
 def _nb_clean(func, *args):
     try:
         return func(*args)
-    except OSError as e:
+    except OSError:
+        _, e = sys.exc_info()[:2]
         if e.errno not in (errno.EWOULDBLOCK, errno.EAGAIN):
             raise
         else:
@@ -88,7 +90,8 @@ def _try_peername(sock):
         pn = sock.getpeername()
         if pn:
             return '%s:%s' % (pn[0], pn[1])
-    except socket.error as e:
+    except socket.error:
+        _, e = sys.exc_info()[:2]
         if e.args[0] not in (errno.ENOTCONN, errno.ENOTSOCK):
             raise
     return 'unknown'
@@ -144,7 +147,8 @@ class SockWrapper:
             self.rsock.connect(self.connect_to)
             # connected successfully (Linux)
             self.connect_to = None
-        except socket.error as e:
+        except socket.error:
+            _, e = sys.exc_info()[:2]
             debug3('%r: connect result: %s\n' % (self, e))
             if e.args[0] == errno.EINVAL:
                 # this is what happens when you call connect() on a socket
@@ -191,7 +195,8 @@ class SockWrapper:
             self.shut_write = True
             try:
                 self.wsock.shutdown(SHUT_WR)
-            except socket.error as e:
+            except socket.error:
+                _, e = sys.exc_info()[:2]
                 self.seterr('nowrite: %s' % e)
 
     def too_full(self):
@@ -203,7 +208,8 @@ class SockWrapper:
         self.wsock.setblocking(False)
         try:
             return _nb_clean(os.write, self.wsock.fileno(), buf)
-        except OSError as e:
+        except OSError:
+            _, e = sys.exc_info()[:2]
             if e.errno == errno.EPIPE:
                 debug1('%r: uwrite: got EPIPE\n' % self)
                 self.nowrite()
@@ -225,9 +231,10 @@ class SockWrapper:
         self.rsock.setblocking(False)
         try:
             return _nb_clean(os.read, self.rsock.fileno(), 65536)
-        except OSError as e:
+        except OSError:
+            _, e = sys.exc_info()[:2]
             self.seterr('uread: %s' % e)
-            return b''  # unexpected error... we'll call it EOF
+            return b('')  # unexpected error... we'll call it EOF
 
     def fill(self):
         if self.buf:
@@ -235,7 +242,7 @@ class SockWrapper:
         rb = self.uread()
         if rb:
             self.buf.append(rb)
-        if rb == b'':  # empty string means EOF; None means temporarily empty
+        if rb == b(''):  # empty string means EOF; None means temporarily empty
             self.noread()
 
     def copy_to(self, outwrap):
@@ -333,11 +340,11 @@ class Mux(Handler):
         self.channels = {}
         self.chani = 0
         self.want = 0
-        self.inbuf = b''
+        self.inbuf = b('')
         self.outbuf = []
         self.fullness = 0
         self.too_full = False
-        self.send(0, CMD_PING, b'chicken')
+        self.send(0, CMD_PING, b('chicken'))
 
     def next_channel(self):
         # channel 0 is special, so we never allocate it
@@ -357,7 +364,7 @@ class Mux(Handler):
     def check_fullness(self):
         if self.fullness > 32768:
             if not self.too_full:
-                self.send(0, CMD_PING, b'rttest')
+                self.send(0, CMD_PING, b('rttest'))
             self.too_full = True
         # ob = []
         # for b in self.outbuf:
@@ -366,9 +373,9 @@ class Mux(Handler):
         # log('outbuf: %d %r\n' % (self.amount_queued(), ob))
 
     def send(self, channel, cmd, data):
-        assert isinstance(data, bytes)
+        assert isinstance(data, binary_type)
         assert len(data) <= 65535
-        p = struct.pack('!ccHHH', b'S', b'S', channel, cmd, len(data)) + data
+        p = struct.pack('!ccHHH', b('S'), b('S'), channel, cmd, len(data)) + data
         self.outbuf.append(p)
         debug2(' > channel=%d cmd=%s len=%d (fullness=%d)\n'
                % (channel, cmd_to_name.get(cmd, hex(cmd)),
@@ -434,14 +441,15 @@ class Mux(Handler):
     def fill(self):
         self.rsock.setblocking(False)
         try:
-            b = _nb_clean(os.read, self.rsock.fileno(), 32768)
+            read = _nb_clean(os.read, self.rsock.fileno(), 32768)
-        except OSError as e:
+        except OSError:
+            _, e = sys.exc_info()[:2]
             raise Fatal('other end: %r' % e)
         # log('<<< %r\n' % b)
-        if b == b'':  # EOF
+        if read == b(''):  # EOF
             self.ok = False
-        if b:
+        if read:
-            self.inbuf += b
+            self.inbuf += read
 
     def handle(self):
         self.fill()
@@ -451,8 +459,8 @@ class Mux(Handler):
             if len(self.inbuf) >= (self.want or HDR_LEN):
                 (s1, s2, channel, cmd, datalen) = \
                     struct.unpack('!ccHHH', self.inbuf[:HDR_LEN])
-                assert(s1 == b'S')
+                assert(s1 == b('S'))
-                assert(s2 == b'S')
+                assert(s2 == b('S'))
                 self.want = datalen + HDR_LEN
             if self.want and len(self.inbuf) >= self.want:
                 data = self.inbuf[HDR_LEN:self.want]
@@ -496,14 +504,14 @@ class MuxWrapper(SockWrapper):
         if not self.shut_read:
             debug2('%r: done reading\n' % self)
             self.shut_read = True
-            self.mux.send(self.channel, CMD_TCP_STOP_SENDING, b'')
+            self.mux.send(self.channel, CMD_TCP_STOP_SENDING, b(''))
             self.maybe_close()
 
     def nowrite(self):
         if not self.shut_write:
             debug2('%r: done writing\n' % self)
             self.shut_write = True
-            self.mux.send(self.channel, CMD_TCP_EOF, b'')
+            self.mux.send(self.channel, CMD_TCP_EOF, b(''))
             self.maybe_close()
 
     def maybe_close(self):
@@ -526,7 +534,7 @@ class MuxWrapper(SockWrapper):
 
     def uread(self):
         if self.shut_read:
-            return b''  # EOF
+            return b('')  # EOF
         else:
             return None  # no data available right now
 

sshuttle/tests/server/test_server.py

@@ -0,0 +1,63 @@
+import io
+import socket
+import sshuttle.server
+from mock import patch, Mock, call
+
+
+def test__ipmatch():
+    assert sshuttle.server._ipmatch("1.2.3.4") is not None
+    assert sshuttle.server._ipmatch("::1") is None   # ipv6 not supported
+    assert sshuttle.server._ipmatch("42 Example Street, Melbourne") is None
+
+
+def test__ipstr():
+    assert sshuttle.server._ipstr("1.2.3.4", 24) == "1.2.3.4/24"
+    assert sshuttle.server._ipstr("1.2.3.4", 32) == "1.2.3.4"
+
+
+def test__maskbits():
+    netmask = sshuttle.server._ipmatch("255.255.255.0")
+    sshuttle.server._maskbits(netmask)
+
+
+@patch('sshuttle.server.ssubprocess.Popen')
+def test__listroutes(mock_popen):
+    mock_pobj = Mock()
+    mock_pobj.stdout = io.BytesIO(b"""
+Kernel IP routing table
+Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
+0.0.0.0         192.168.1.1     0.0.0.0         UG        0 0          0 wlan0
+192.168.1.0     0.0.0.0         255.255.255.0   U         0 0          0 wlan0
+""")
+    mock_pobj.wait.return_value = 0
+    mock_popen.return_value = mock_pobj
+
+    routes = sshuttle.server._list_routes()
+
+    assert mock_popen.mock_calls == [
+        call(['netstat', '-rn'], stdout=-1),
+        call().wait()
+    ]
+    assert routes == [
+        (socket.AF_INET, '0.0.0.0', 0),
+        (socket.AF_INET, '192.168.1.0', 24)
+    ]
+
+
+@patch('sshuttle.server.ssubprocess.Popen')
+def test_listroutes(mock_popen):
+    mock_pobj = Mock()
+    mock_pobj.stdout = io.BytesIO(b"""
+Kernel IP routing table
+Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
+0.0.0.0         192.168.1.1     0.0.0.0         UG        0 0          0 wlan0
+192.168.1.0     0.0.0.0         255.255.255.0   U         0 0          0 wlan0
+""")
+    mock_pobj.wait.return_value = 0
+    mock_popen.return_value = mock_pobj
+
+    routes = sshuttle.server.list_routes()
+
+    assert list(routes) == [
+        (socket.AF_INET, '192.168.1.0', 24)
+    ]

tox.ini

@@ -1,12 +1,16 @@
 [tox]
 downloadcache = {toxworkdir}/cache/
 envlist =
+    py26,
     py27,
+    py34,
     py35,
 
 [testenv]
 basepython =
+    py26: python2.6
     py27: python2.7
+    py34: python3.4
     py35: python3.5
 commands =
     py.test