Merge pull request #19 from naclander/patch-1

Remove no-latency-control assertion

.gitignore

@@ -1,3 +1,6 @@
 *.pyc
 *~
 *.8
+/.do_built
+/.do_built.dir
+/.redo

Makefile

@@ -1,19 +0,0 @@
-PANDOC:=$(shell \
-	if pandoc </dev/null 2>/dev/null; then \
-		echo pandoc; \
-	else \
-		echo "Warning: pandoc not installed; can't generate manpages." >&2; \
-		echo '@echo Skipping: pandoc'; \
-	fi)
-
-default: all
-
-all: sshuttle.8
-
-sshuttle.8: sshuttle.md
-
-%.8: %.md
-	$(PANDOC) -s -r markdown -w man -o $@ $<
-
-clean:
-	rm -f *~ */*~ .*~ */.*~ *.8 *.tmp */*.tmp *.pyc */*.pyc

README.md

@@ -1,3 +1,28 @@
+
+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.
+
+Required Software
+=================
+
+ - You need PyXAPI, available here:
+   http://www.pps.univ-paris-diderot.fr/~ylg/PyXAPI/
+ - Python 2.x, both locally and the remote system
+
+
+Additional Suggested Software
+-----------------------------
+
+ - You may want to need autossh, available in various package management
+   systems
+
+
 sshuttle: where transparent proxy meets VPN meets ssh
 =====================================================
 
@@ -40,19 +65,46 @@ Prerequisites
    Linux.)
    
  - If you use MacOS or BSD on your client machine:
-   Your kernel needs to be compiled with IPFIREWALL_FORWARD
+   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:
+Obtaining sshuttle
+------------------
+
+ - First, go get PyXAPI from the link above
+
+ - Clone: `git clone https://github.com/sshuttle/sshuttle.git`
+
+
+Usage on (Ubuntu) Linux
 -----------------------
 
- - <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.
+ - `cd packaging; ./make_deb`
 
- - <tt>./sshuttle -r username@sshserver 0.0.0.0/0 -vv</tt>
+ - `sudo dpkg -i ./sshuttle-VERSION.deb`
+
+ - Check out the files in `/etc/sshuttle`; configure them so your tunnel works
+
+ - `sudo service sshuttle start`
+
+
+Usage on other Linuxes and OSes
+-------------------------------
+
+  <tt>src/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>src/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>src/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
@@ -60,6 +112,9 @@ 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.

client.py

@@ -1,354 +0,0 @@
-import struct, socket, select, errno, re, signal
-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 _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
-
-
-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):
-        self.port = port
-        self.auto_nets = []
-        self.subnets_include = subnets_include
-        self.subnets_exclude = subnets_exclude
-        argvbase = ([sys.argv[0]] +
-                    ['-v'] * (helpers.verbose or 0) +
-                    ['--firewall', str(port)])
-        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:
-            raise Fatal('cleanup: %r returned %d' % (self.argv, rv))
-
-
-def _main(listener, fw, ssh_cmd, remotename, python, 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)
-    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:
-        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')
-    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
-
-    def onaccept():
-        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()
-        mux.send(chan, ssnet.CMD_CONNECT, '%s,%s' % dstip)
-        outwrap = MuxWrapper(mux, chan)
-        handlers.append(Proxy(SockWrapper(sock, sock), outwrap))
-    handlers.append(Handler([listener], onaccept))
-
-    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)
-        mux.callback()
-        mux.check_fullness()
-
-
-def main(listenip, ssh_cmd, remotename, python, 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')
-    listener = socket.socket()
-    listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
-    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)
-        try:
-            listener.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,))
-
-    fw = FirewallClient(listenip[1], subnets_include, subnets_exclude)
-    
-    try:
-        return _main(listener, fw, ssh_cmd, remotename,
-                     python, 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()

firewall.py

@@ -1,304 +0,0 @@
-import re, errno
-import compat.ssubprocess as ssubprocess
-import helpers, ssyslog
-from helpers import *
-
-
-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)
-    debug1('>> %s\n' % ' '.join(argv))
-    rv = ssubprocess.call(argv)
-    if rv:
-        raise Fatal('%r returned %d' % (argv, rv))
-
-
-# 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, subnets):
-    chain = 'sshuttle-%s' % port
-
-    # basic cleanup/setup of chains
-    if ipt_chain_exists(chain):
-        ipt('-D', 'OUTPUT', '-j', chain)
-        ipt('-D', 'PREROUTING', '-j', chain)
-        ipt('-F', chain)
-        ipt('-X', chain)
-
-    if subnets:
-        ipt('-N', chain)
-        ipt('-F', chain)
-        ipt('-I', 'OUTPUT', '1', '-j', chain)
-        ipt('-I', 'PREROUTING', '1', '-j', chain)
-
-        # 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('-A', chain, '-j', 'REDIRECT',
-                    '--dest', '%s/%s' % (snet,swidth),
-                    '-p', 'tcp',
-                    '--to-ports', str(port),
-                    '-m', 'ttl', '!', '--ttl', '42'  # to prevent infinite loops
-                    )
-
-
-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 setup keep-state' 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,))
-
-
-def _sysctl_set(name, val):
-    argv = ['sysctl', '-w', '%s=%s' % (name, val)]
-    debug1('>> %s\n' % ' '.join(argv))
-    rv = ssubprocess.call(argv, stdout = open('/dev/null', 'w'))
-
-
-_changedctls = []
-def sysctl_set(name, val):
-    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
-    oldval = _oldctls[name]
-    if val != oldval:
-        _changedctls.append(name)
-        return _sysctl_set(name, val)
-    
-
-def ipfw(*args):
-    argv = ['ipfw', '-q'] + list(args)
-    debug1('>> %s\n' % ' '.join(argv))
-    rv = ssubprocess.call(argv)
-    if rv:
-        raise Fatal('%r returned %d' % (argv, rv))
-
-
-def do_ipfw(port, 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:
-        sysctl_set('net.inet.ip.fw.enable', 1)
-        sysctl_set('net.inet.ip.scopedroute', 0)
-
-        ipfw('add', sport, 'check-state', 'ip',
-             'from', 'any', 'to', 'any')
-        
-        # create new subnet entries
-        for swidth,sexclude,snet in sorted(subnets, reverse=True):
-            if sexclude:
-                ipfw('add', sport, 'skipto', xsport,
-                     'log', 'tcp',
-                     'from', 'any', 'to', '%s/%s' % (snet,swidth))
-            else:
-                ipfw('add', sport, 'fwd', '127.0.0.1,%d' % port,
-                     'log', 'tcp',
-                     'from', 'any', 'to', '%s/%s' % (snet,swidth),
-                     'not', 'ipttl', '42', 'keep-state', 'setup')
-
-
-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, syslog):
-    assert(port > 0)
-    assert(port <= 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()
-
-    # 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_it(port, 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:
-            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, [])
-        restore_etc_hosts(port)

helpers.py

@@ -1,37 +0,0 @@
-import sys, os
-
-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
-
-
-def list_contains_any(l, sub):
-    for i in sub:
-        if i in l:
-            return True
-    return False

main.py

@@ -1,122 +0,0 @@
-#!/usr/bin/env python
-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
-python=    path to python interpreter on the remote server [python]
-r,remote=  ssh hostname (and optional username) of remote sshuttle server
-x,exclude= exclude this subnet (can be used more than once)
-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)
-D,daemon   run in the background as a daemon
-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('sshuttle', optspec)
-(opt, flags, extra) = o.parse(sys.argv[1:])
-
-if opt.daemon:
-    opt.syslog = 1
-helpers.verbose = opt.verbose
-
-try:
-    if opt.server:
-        if len(extra) != 0:
-            o.fatal('no arguments expected')
-        sys.exit(server.main())
-    elif opt.firewall:
-        if len(extra) != 1:
-            o.fatal('exactly one argument expected')
-        sys.exit(firewall.main(int(extra[0]), 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)
-        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,
-                             sh,
-                             opt.auto_nets,
-                             parse_subnets(includes),
-                             parse_subnets(excludes),
-                             opt.syslog, opt.daemon, opt.pidfile))
-except Fatal, e:
-    log('fatal: %s\n' % e)
-    sys.exit(99)
-except KeyboardInterrupt:
-    log('\n')
-    log('Keyboard interrupt: exiting.\n')
-    sys.exit(1)

packaging/control

@@ -0,0 +1,28 @@
+Package: sshuttle
+Version: 0+git
+Architecture: all
+Maintainer: Jim Wyllie <jwyllie83@gmail.com>
+Depends: iptables, python (>= 2.6)
+Suggests: autossh
+Section: net
+Priority: optional
+Homepage: http://github.com/sshuttle/sshuttle
+Description: "Full-featured" VPN over an SSH tunnel
+ It allows full remote access somewhere where all you have is an SSH
+ connection.  It works well if you generally find yourself in the
+ following situation:
+ .
+ - 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.
+ - You do not wish to, or can't, use other VPN software
+ - 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 suboptimal performance
+ .
+ It also has hooks for more complicated setups (VPN-in-a-SSH-VPN, etc.) to allow
+ you to set it up as you like.

packaging/make_deb

@@ -0,0 +1,46 @@
+#!/bin/bash
+#
+# This script puts together a .deb package suitable for installing on an Ubuntu
+# system
+
+B="/tmp/sshuttle/build"
+
+if [ ! -x /usr/bin/dpkg ]; then
+	echo 'Unable to build: dpkg not found on system'
+	exit 1
+fi
+
+# Create the new directory structure
+mkdir -p ${B}/etc/sshuttle/pre-start.d
+mkdir -p ${B}/etc/sshuttle/post-stop.d
+mkdir -p ${B}/usr/share/sshuttle
+mkdir -p ${B}/usr/bin
+mkdir -p ${B}/etc/init
+mkdir -p ${B}/DEBIAN
+
+# Copy over all of the files
+cp -r ../src/* ${B}/usr/share/sshuttle
+cp ../src/sshuttle ${B}/usr/bin
+cp -r sshuttle.conf ${B}/etc/init
+cp prefixes.conf ${B}/etc/sshuttle
+cp tunnel.conf ${B}/etc/sshuttle
+# Remove MacOS X stuff from .deb
+rm -r ${B}/usr/share/sshuttle/ui-macos
+
+# Fix path to main.py
+sed -e 's:^DIR=.*$:DIR=/usr/share/sshuttle/:' -i ${B}/usr/bin/sshuttle
+
+# Copy the control file over, as well
+cp control ${B}/DEBIAN
+
+# Create the md5sum manifest
+if [ -x /usr/bin/md5sum ]; then
+	cd ${B}
+	find . -type f | egrep -v DEBIAN | sed -re 's/^..//' | xargs md5sum > ${B}/DEBIAN/md5sums
+	cd ${OLDPWD}
+fi
+
+# Build the debian package
+VERSION=$(egrep -e '^Version' control | sed -re 's/^[^:]*: //')
+dpkg --build ${B} ./sshuttle-${VERSION}.deb
+rm -rf ${B}

packaging/prefixes.conf

@@ -0,0 +1,5 @@
+# Output prefixes here, one per line.  Prefix is in:
+# prefix/netmask format
+# Like this:
+# 192.168.0.0/16
+# 192.0.43.10/32

packaging/sshuttle.conf

@@ -0,0 +1,90 @@
+description "Create a transparent proxy over SSH"
+author      "Jim Wyllie <jwyllie83@gmail.com>"
+
+manual
+nice -5
+
+# Edit this file with network prefixes that should be loaded through the SSH
+# tunnel.
+env PREFIX_LOCATION=/etc/sshuttle/prefixes.conf
+
+# Routing table; defaults to 100
+env ROUTE_TABLE=100
+
+# fwmark; defaults to 1
+env FWMARK=1
+
+# SSH tunnel configuration file
+env SSHUTTLE_TUNNEL_FILE=/etc/sshuttle/tunnel.conf
+
+# File containing the tunnel proxy name / host / whatever
+env TUNNEL_PROXY="/etc/sshuttle/tunnel.conf"
+
+# Any other commands needed to run before or after loading the SSH tunnel.
+# This is where you can put any of your hacks to set up tunnels-in-tunnels,
+# etc.  Scripts in this directory are executed in order.
+env MISC_START_DIR=/etc/sshuttle/pre-start.d
+env MISC_STOP_DIR=/etc/sshuttle/post-stop.d
+
+start on (local-filesystems and net-device-up IFACE!=lo)
+stop on stopping network-services
+
+#respawn
+
+pre-start script
+	# Make sure we have created the routes
+	sudo ip rule add fwmark ${FWMARK} lookup ${ROUTE_TABLE}
+	logger "Starting sshuttle..."
+
+	if [ -f "${PREFIX_LOCATION}" ]; then
+		cat "${PREFIX_LOCATION}" | while read ROUTE; do
+
+			# Skip comments
+			if [ -n "$(echo ${ROUTE} | egrep "^[ 	]*#")" ]; then
+				continue
+			fi
+
+			# Skip empty lines
+			if [ -z "${ROUTE}" ]; then
+				continue
+			fi
+
+			logger "Adding route: ${ROUTE}"
+			ip route add local ${ROUTE} dev lo table ${ROUTE_TABLE}
+		done
+	fi
+
+	for RUNFILE in ${MISC_START_DIR}/*; do
+		logger "Executing ${RUNFILE}"
+		/bin/sh -c "${RUNFILE}"
+	done
+end script
+
+post-stop script
+	if [ -f "${PREFIX_LOCATION}" ]; then
+		cat "${PREFIX_LOCATION}" | while read ROUTE; do
+
+			# Skip comments
+			if [ -n "$(echo ${ROUTE} | egrep "^[ 	]*#")" ]; then
+				continue
+			fi
+
+			# Skip empty lines
+			if [ -z "${ROUTE}" ]; then
+				continue
+			fi
+
+			logger "Deleting route: ${ROUTE}"
+			ip route del local ${ROUTE} dev lo table ${ROUTE_TABLE}
+		done
+	fi
+
+	ip rule del fwmark ${FWMARK}
+
+	for RUNFILE in "${MISC_STOP_DIR}/*"; do
+		logger "Executing ${RUNFILE}"
+		/bin/sh -c "${RUNFILE}"
+	done
+end script
+
+exec /usr/bin/sshuttle --dns --method=tproxy --listen 0.0.0.0 --remote sshuttle_tunnel -s /etc/sshuttle/prefixes.conf -e "ssh -F ${TUNNEL_PROXY}"

packaging/tunnel.conf

@@ -0,0 +1,19 @@
+# Here is where you can specify any SSH tunnel options See ssh_config(5) for
+# details.  You need to leave the Host line intact, but everything else can
+# specify whatever you want
+Host sshuttle_tunnel
+
+# REQUIRED: Set this to be the host to which you would like to connect your
+# tunnel
+#Hostname localhost
+
+# REQUIRED: Set this to be the target SSH user on the remote system
+#User foo
+
+# ---------------------------------------------------------------------------
+# The rest are all optional; see ssh_config(5) for the full list of what can
+# be specified.  Some very commonly needed ones are below.
+# ---------------------------------------------------------------------------
+
+# SSH key used for connecting
+#IdentityFile /path/to/key

server.py

@@ -1,176 +0,0 @@
-import re, struct, socket, select, traceback
-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):
-    return n * int(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():
-    for (ip,width) in _list_routes():
-        if not ip.startswith('0.') and not ip.startswith('127.'):
-            yield (ip,width)
-
-
-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
-
-
-def main():
-    if helpers.verbose >= 1:
-        helpers.logprefix = ' s: '
-    else:
-        helpers.logprefix = 'server: '
-
-    routes = list(list_routes())
-    debug1('available routes:\n')
-    for r in routes:
-        debug1('  %s/%d\n' % r)
-        
-    # synchronization header
-    sys.stdout.write('SSHUTTLE0001')
-    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
-
-    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)
-        mux.check_fullness()
-        mux.callback()

src/Makefile

@@ -0,0 +1,10 @@
+all:
+
+Makefile:
+	@
+
+%: FORCE
+	+./do $@
+
+.PHONY: FORCE
+

src/all.do

@@ -0,0 +1,11 @@
+exec >&2
+UI=
+[ "$(uname)" = "Darwin" ] && UI=ui-macos/all
+redo-ifchange sshuttle.8 $UI
+
+echo
+echo "What now?"
+[ -z "$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 sshuttle.md"

src/assembler.py

@@ -1,4 +1,5 @@
-import sys, zlib
+import sys
+import zlib
 
 z = zlib.decompressobj()
 mainmod = sys.modules[__name__]

src/clean.do

@@ -0,0 +1,2 @@
+redo ui-macos/clean
+rm -f *~ */*~ .*~ */.*~ *.8 *.tmp */*.tmp *.pyc */*.pyc

src/client.py

@@ -0,0 +1,776 @@
+import struct
+import errno
+import re
+import signal
+import time
+import compat.ssubprocess as ssubprocess
+import helpers
+import os
+import ssnet
+import ssh
+import ssyslog
+import sys
+from ssnet import SockWrapper, Handler, Proxy, Mux, MuxWrapper
+from helpers import log, debug1, debug2, debug3, Fatal, islocal
+
+recvmsg = None
+try:
+    # try getting recvmsg from python
+    import socket as pythonsocket
+    getattr(pythonsocket.socket, "recvmsg")
+    socket = pythonsocket
+    recvmsg = "python"
+except AttributeError:
+    # try getting recvmsg from socket_ext library
+    try:
+        import socket_ext
+        getattr(socket_ext.socket, "recvmsg")
+        socket = socket_ext
+        recvmsg = "socket_ext"
+    except ImportError:
+        import socket
+
+_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
+IP_TRANSPARENT = 19
+IP_ORIGDSTADDR = 20
+IP_RECVORIGDSTADDR = IP_ORIGDSTADDR
+SOL_IPV6 = 41
+IPV6_ORIGDSTADDR = 74
+IPV6_RECVORIGDSTADDR = IPV6_ORIGDSTADDR
+
+
+if recvmsg == "python":
+    def recv_udp(listener, bufsize):
+        debug3('Accept UDP python using recvmsg.\n')
+        data, ancdata, msg_flags, 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)
+elif recvmsg == "socket_ext":
+    def recv_udp(listener, bufsize):
+        debug3('Accept UDP using socket_ext recvmsg.\n')
+        srcip, data, adata, flags = listener.recvmsg(
+            (bufsize,), socket.CMSG_SPACE(24))
+        dstip = None
+        family = None
+        for a in adata:
+            if a.cmsg_level == socket.SOL_IP and a.cmsg_type == IP_ORIGDSTADDR:
+                family, port = struct.unpack('=HH', a.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, a.cmsg_data[start:start + length])
+                dstip = (ip, port)
+                break
+            elif a.cmsg_level == SOL_IPV6 and a.cmsg_type == IPV6_ORIGDSTADDR:
+                family, port = struct.unpack('=HH', a.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, a.cmsg_data[start:start + length])
+                dstip = (ip, port)
+                break
+        return (srcip, dstip, data[0])
+else:
+    def recv_udp(listener, bufsize):
+        debug3('Accept UDP using recvfrom.\n')
+        data, srcip = listener.recvfrom(bufsize)
+        return (srcip, None, data)
+
+
+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
+
+pf_command_file = None
+
+def pf_dst(sock):
+    peer = sock.getpeername()
+    proxy = sock.getsockname()
+
+    argv = (sock.family, socket.IPPROTO_TCP, peer[0], peer[1], proxy[0], proxy[1])
+    pf_command_file.write("QUERY_PF_NAT %r,%r,%s,%r,%s,%r\n" % argv)
+    pf_command_file.flush()
+    line = pf_command_file.readline()
+    debug2("QUERY_PF_NAT %r,%r,%s,%r,%s,%r" % argv + ' > ' + line)
+    if line.startswith('QUERY_PF_NAT_SUCCESS '):
+        (ip, port) = line[21:].split(',')
+        return (ip, int(port))
+
+    return sock.getsockname()
+
+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 MultiListener:
+
+    def __init__(self, type=socket.SOCK_STREAM, proto=0):
+        self.v6 = socket.socket(socket.AF_INET6, type, proto)
+        self.v4 = socket.socket(socket.AF_INET, type, proto)
+
+    def setsockopt(self, level, optname, value):
+        if self.v6:
+            self.v6.setsockopt(level, optname, value)
+        if self.v4:
+            self.v4.setsockopt(level, optname, value)
+
+    def add_handler(self, handlers, callback, method, mux):
+        if self.v6:
+            handlers.append(
+                Handler(
+                    [self.v6],
+                    lambda: callback(self.v6, method, mux, handlers)))
+        if self.v4:
+            handlers.append(
+                Handler(
+                    [self.v4],
+                    lambda: callback(self.v4, method, mux, handlers)))
+
+    def listen(self, backlog):
+        if self.v6:
+            self.v6.listen(backlog)
+        if self.v4:
+            try:
+                self.v4.listen(backlog)
+            except socket.error, e:
+                # on some systems v4 bind will fail if the v6 suceeded,
+                # in this case the v6 socket will receive v4 too.
+                if e.errno == errno.EADDRINUSE and self.v6:
+                    self.v4 = None
+                else:
+                    raise e
+
+    def bind(self, address_v6, address_v4):
+        if address_v6 and self.v6:
+            self.v6.bind(address_v6)
+        else:
+            self.v6 = None
+        if address_v4 and self.v4:
+            self.v4.bind(address_v4)
+        else:
+            self.v4 = None
+
+    def print_listening(self, what):
+        if self.v6:
+            listenip = self.v6.getsockname()
+            debug1('%s listening on %r.\n' % (what, listenip))
+        if self.v4:
+            listenip = self.v4.getsockname()
+            debug1('%s listening on %r.\n' % (what, listenip))
+
+
+class FirewallClient:
+
+    def __init__(self, port_v6, port_v4, subnets_include, subnets_exclude,
+                 dnsport_v6, dnsport_v4, method, udp):
+        self.auto_nets = []
+        self.subnets_include = subnets_include
+        self.subnets_exclude = subnets_exclude
+        argvbase = ([sys.argv[1], sys.argv[0], sys.argv[1]] +
+                    ['-v'] * (helpers.verbose or 0) +
+                    ['--firewall', str(port_v6), str(port_v4),
+                     str(dnsport_v6), str(dnsport_v4),
+                     method, str(int(udp))])
+        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[0:5] != 'READY':
+            raise Fatal('%r expected READY, got %r' % (self.argv, line))
+        self.method = line[6:-1]
+
+    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 (family, ip, width) in self.subnets_include + self.auto_nets:
+            self.pfile.write('%d,%d,0,%s\n' % (family, width, ip))
+        for (family, ip, width) in self.subnets_exclude:
+            self.pfile.write('%d,%d,1,%s\n' % (family, 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:
+            raise Fatal('cleanup: %r returned %d' % (self.argv, rv))
+
+
+dnsreqs = {}
+udp_by_src = {}
+
+
+def expire_connections(now, mux):
+    for chan, timeout in dnsreqs.items():
+        if timeout < now:
+            debug3('expiring dnsreqs channel=%d\n' % chan)
+            del mux.channels[chan]
+            del dnsreqs[chan]
+    debug3('Remaining DNS requests: %d\n' % len(dnsreqs))
+    for peer, (chan, timeout) in udp_by_src.items():
+        if timeout < now:
+            debug3('expiring UDP channel channel=%d peer=%r\n' % (chan, peer))
+            mux.send(chan, ssnet.CMD_UDP_CLOSE, '')
+            del mux.channels[chan]
+            del udp_by_src[peer]
+    debug3('Remaining UDP channels: %d\n' % len(udp_by_src))
+
+
+def onaccept_tcp(listener, method, 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
+    if method == "tproxy":
+        dstip = sock.getsockname()
+    elif method == "pf":
+        dstip = pf_dst(sock)
+    else:
+        dstip = original_dst(sock)
+    debug1('Accept TCP: %s:%r -> %s:%r.\n' % (srcip[0], srcip[1],
+                                              dstip[0], dstip[1]))
+    if dstip[1] == sock.getsockname()[1] and islocal(dstip[0], sock.family):
+        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_TCP_CONNECT, '%d,%s,%s' %
+             (sock.family, dstip[0], dstip[1]))
+    outwrap = MuxWrapper(mux, chan)
+    handlers.append(Proxy(SockWrapper(sock, sock), outwrap))
+    expire_connections(time.time(), mux)
+
+
+def udp_done(chan, data, method, family, dstip):
+    (src, srcport, data) = data.split(",", 2)
+    srcip = (src, int(srcport))
+    debug3('doing send from %r to %r\n' % (srcip, dstip,))
+
+    try:
+        sender = socket.socket(family, socket.SOCK_DGRAM)
+        sender.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        sender.setsockopt(socket.SOL_IP, IP_TRANSPARENT, 1)
+        sender.bind(srcip)
+        sender.sendto(data, dstip)
+        sender.close()
+    except socket.error, e:
+        debug1('-- ignored socket error sending UDP data: %r\n' % e)
+
+
+def onaccept_udp(listener, method, mux, handlers):
+    now = time.time()
+    srcip, dstip, data = recv_udp(listener, 4096)
+    if not dstip:
+        debug1(
+            "-- ignored UDP from %r: "
+            "couldn't determine destination IP address\n" % (srcip,))
+        return
+    debug1('Accept UDP: %r -> %r.\n' % (srcip, dstip,))
+    if srcip in udp_by_src:
+        chan, timeout = udp_by_src[srcip]
+    else:
+        chan = mux.next_channel()
+        mux.channels[chan] = lambda cmd, data: udp_done(
+            chan, data, method, listener.family, dstip=srcip)
+        mux.send(chan, ssnet.CMD_UDP_OPEN, listener.family)
+    udp_by_src[srcip] = chan, now + 30
+
+    hdr = "%s,%r," % (dstip[0], dstip[1])
+    mux.send(chan, ssnet.CMD_UDP_DATA, hdr + data)
+
+    expire_connections(now, mux)
+
+
+def dns_done(chan, data, method, sock, srcip, dstip, mux):
+    debug3('dns_done: channel=%d src=%r dst=%r\n' % (chan, srcip, dstip))
+    del mux.channels[chan]
+    del dnsreqs[chan]
+    if method == "tproxy":
+        debug3('doing send from %r to %r\n' % (srcip, dstip,))
+        sender = socket.socket(sock.family, socket.SOCK_DGRAM)
+        sender.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        sender.setsockopt(socket.SOL_IP, IP_TRANSPARENT, 1)
+        sender.bind(srcip)
+        sender.sendto(data, dstip)
+        sender.close()
+    else:
+        debug3('doing sendto %r\n' % (dstip,))
+        sock.sendto(data, dstip)
+
+
+def ondns(listener, method, mux, handlers):
+    now = time.time()
+    srcip, dstip, data = recv_udp(listener, 4096)
+    if method == "tproxy" and not dstip:
+        debug1(
+            "-- ignored UDP from %r: "
+            "couldn't determine destination IP address\n" % (srcip,))
+        return
+    debug1('DNS request from %r to %r: %d bytes\n' % (srcip, dstip, len(data)))
+    chan = mux.next_channel()
+    dnsreqs[chan] = now + 30
+    mux.send(chan, ssnet.CMD_DNS_REQ, data)
+    mux.channels[chan] = lambda cmd, data: dns_done(
+        chan, data, method, listener, srcip=dstip, dstip=srcip, mux=mux)
+    expire_connections(now, mux)
+
+
+def _main(tcp_listener, udp_listener, fw, ssh_cmd, remotename,
+          python, latency_control,
+          dns_listener, method, 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, method=method))
+    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'):
+                (family, ip, width) = line.split(',', 2)
+                fw.auto_nets.append((int(family), 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
+
+    tcp_listener.add_handler(handlers, onaccept_tcp, method, mux)
+
+    if udp_listener:
+        udp_listener.add_handler(handlers, onaccept_udp, method, mux)
+
+    if dns_listener:
+        dns_listener.add_handler(handlers, ondns, method, mux)
+
+    if seed_hosts is not 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_v6, listenip_v4,
+         ssh_cmd, remotename, python, latency_control, dns,
+         method, 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 recvmsg is not None:
+        debug1("recvmsg %s support enabled.\n" % recvmsg)
+
+    if method == "tproxy":
+        if recvmsg is not None:
+            debug1("tproxy UDP support enabled.\n")
+            udp = True
+        else:
+            debug1("tproxy UDP support requires recvmsg function.\n")
+            udp = False
+        if dns and recvmsg is None:
+            debug1("tproxy DNS support requires recvmsg function.\n")
+            dns = False
+    else:
+        debug1("UDP support requires tproxy; disabling UDP.\n")
+        udp = False
+
+    if listenip_v6 and listenip_v6[1] and listenip_v4 and listenip_v4[1]:
+        # if both ports given, no need to search for a spare port
+        ports = [0, ]
+    else:
+        # if at least one port missing, we have to search
+        ports = xrange(12300, 9000, -1)
+
+    # search for free ports and try to bind
+    last_e = None
+    redirectport_v6 = 0
+    redirectport_v4 = 0
+    bound = False
+    debug2('Binding redirector:')
+    for port in ports:
+        debug2(' %d' % port)
+        tcp_listener = MultiListener()
+        tcp_listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+
+        if udp:
+            udp_listener = MultiListener(socket.SOCK_DGRAM)
+            udp_listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        else:
+            udp_listener = None
+
+        if listenip_v6 and listenip_v6[1]:
+            lv6 = listenip_v6
+            redirectport_v6 = lv6[1]
+        elif listenip_v6:
+            lv6 = (listenip_v6[0], port)
+            redirectport_v6 = port
+        else:
+            lv6 = None
+            redirectport_v6 = 0
+
+        if listenip_v4 and listenip_v4[1]:
+            lv4 = listenip_v4
+            redirectport_v4 = lv4[1]
+        elif listenip_v4:
+            lv4 = (listenip_v4[0], port)
+            redirectport_v4 = port
+        else:
+            lv4 = None
+            redirectport_v4 = 0
+
+        try:
+            tcp_listener.bind(lv6, lv4)
+            if udp_listener:
+                udp_listener.bind(lv6, lv4)
+            bound = True
+            break
+        except socket.error, e:
+            if e.errno == errno.EADDRINUSE:
+                last_e = e
+            else:
+                raise e
+    debug2('\n')
+    if not bound:
+        assert(last_e)
+        raise last_e
+    tcp_listener.listen(10)
+    tcp_listener.print_listening("TCP redirector")
+    if udp_listener:
+        udp_listener.print_listening("UDP redirector")
+
+    bound = False
+    if dns:
+        # search for spare port for DNS
+        debug2('Binding DNS:')
+        ports = xrange(12300, 9000, -1)
+        for port in ports:
+            debug2(' %d' % port)
+            dns_listener = MultiListener(socket.SOCK_DGRAM)
+
+            if listenip_v6:
+                lv6 = (listenip_v6[0], port)
+                dnsport_v6 = port
+            else:
+                lv6 = None
+                dnsport_v6 = 0
+
+            if listenip_v4:
+                lv4 = (listenip_v4[0], port)
+                dnsport_v4 = port
+            else:
+                lv4 = None
+                dnsport_v4 = 0
+
+            try:
+                dns_listener.bind(lv6, lv4)
+                bound = True
+                break
+            except socket.error, e:
+                if e.errno == errno.EADDRINUSE:
+                    last_e = e
+                else:
+                    raise e
+        debug2('\n')
+        dns_listener.print_listening("DNS")
+        if not bound:
+            assert(last_e)
+            raise last_e
+    else:
+        dnsport_v6 = 0
+        dnsport_v4 = 0
+        dns_listener = None
+
+    fw = FirewallClient(redirectport_v6, redirectport_v4, subnets_include,
+                        subnets_exclude, dnsport_v6, dnsport_v4, method, udp)
+
+    if fw.method == "tproxy":
+        tcp_listener.setsockopt(socket.SOL_IP, IP_TRANSPARENT, 1)
+        if udp_listener:
+            udp_listener.setsockopt(socket.SOL_IP, IP_TRANSPARENT, 1)
+            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)
+        if dns_listener:
+            dns_listener.setsockopt(socket.SOL_IP, IP_TRANSPARENT, 1)
+            if dns_listener.v4 is not None:
+                dns_listener.v4.setsockopt(
+                    socket.SOL_IP, IP_RECVORIGDSTADDR, 1)
+            if dns_listener.v6 is not None:
+                dns_listener.v6.setsockopt(SOL_IPV6, IPV6_RECVORIGDSTADDR, 1)
+
+    if fw.method == "pf":
+        global pf_command_file
+        pf_command_file = fw.pfile
+
+    try:
+        return _main(tcp_listener, udp_listener, fw, ssh_cmd, remotename,
+                     python, latency_control, dns_listener,
+                     fw.method, 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()

src/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

src/do

@@ -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

src/firewall.py

@@ -0,0 +1,832 @@
+import errno
+import socket
+import select
+import signal
+import struct
+import compat.ssubprocess as ssubprocess
+import ssyslog
+import sys
+import os
+import re
+from helpers import log, debug1, debug3, islocal, Fatal, family_to_string, \
+    resolvconf_nameservers
+from fcntl import ioctl
+from ctypes import c_char, c_uint8, c_uint16, c_uint32, Union, Structure, \
+	sizeof, addressof, memmove
+
+
+# python doesn't have a definition for this
+IPPROTO_DIVERT = 254
+
+
+def nonfatal(func, *args):
+    try:
+        func(*args)
+    except Fatal, e:
+        log('error: %s\n' % 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, '-t', table, '-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(family, table, *args):
+    if family == socket.AF_INET6:
+        argv = ['ip6tables', '-t', table] + list(args)
+    elif family == socket.AF_INET:
+        argv = ['iptables', '-t', table] + list(args)
+    else:
+        raise Exception('Unsupported family "%s"' % family_to_string(family))
+    debug1('>> %s\n' % ' '.join(argv))
+    rv = ssubprocess.call(argv)
+    if rv:
+        raise Fatal('%r returned %d' % (argv, rv))
+
+
+_no_ttl_module = False
+
+
+def _ipt_ttl(family, *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(family, *argsplus)
+        except Fatal:
+            _ipt(family, *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(family, *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_nat(port, dnsport, family, subnets, udp):
+    # only ipv4 supported with NAT
+    if family != socket.AF_INET:
+        raise Exception(
+            'Address family "%s" unsupported by nat method'
+            % family_to_string(family))
+    if udp:
+        raise Exception("UDP not supported by nat method")
+
+    table = "nat"
+
+    def ipt(*args):
+        return _ipt(family, table, *args)
+
+    def ipt_ttl(*args):
+        return _ipt_ttl(family, table, *args)
+
+    chain = 'sshuttle-%s' % port
+
+    # basic cleanup/setup of chains
+    if ipt_chain_exists(family, table, 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 f, swidth, sexclude, snet \
+                in sorted(subnets, key=lambda s: s[1], 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 f, ip in filter(lambda i: i[0] == family, nslist):
+            ipt_ttl('-A', chain, '-j', 'REDIRECT',
+                    '--dest', '%s/32' % ip,
+                    '-p', 'udp',
+                    '--dport', '53',
+                    '--to-ports', str(dnsport))
+
+
+def do_iptables_tproxy(port, dnsport, family, subnets, udp):
+    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_ttl(*args):
+        return _ipt_ttl(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)
+
+    if subnets or dnsport:
+        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)
+        ipt('-A', divert_chain, '-j', 'MARK', '--set-mark', '1')
+        ipt('-A', divert_chain, '-j', 'ACCEPT')
+        ipt('-A', tproxy_chain, '-m', 'socket', '-j', divert_chain,
+            '-m', 'tcp', '-p', 'tcp')
+    if subnets and udp:
+        ipt('-A', tproxy_chain, '-m', 'socket', '-j', divert_chain,
+            '-m', 'udp', '-p', 'udp')
+
+    if dnsport:
+        nslist = resolvconf_nameservers()
+        for f, ip in filter(lambda i: i[0] == family, nslist):
+            ipt('-A', mark_chain, '-j', 'MARK', '--set-mark', '1',
+                '--dest', '%s/32' % ip,
+                '-m', 'udp', '-p', 'udp', '--dport', '53')
+            ipt('-A', tproxy_chain, '-j', 'TPROXY', '--tproxy-mark', '0x1/0x1',
+                '--dest', '%s/32' % ip,
+                '-m', 'udp', '-p', 'udp', '--dport', '53',
+                '--on-port', str(dnsport))
+
+    if subnets:
+        for f, swidth, sexclude, snet \
+                in sorted(subnets, key=lambda s: s[1], reverse=True):
+            if sexclude:
+                ipt('-A', mark_chain, '-j', 'RETURN',
+                    '--dest', '%s/%s' % (snet, swidth),
+                    '-m', 'tcp', '-p', 'tcp')
+                ipt('-A', tproxy_chain, '-j', 'RETURN',
+                    '--dest', '%s/%s' % (snet, swidth),
+                    '-m', 'tcp', '-p', 'tcp')
+            else:
+                ipt('-A', mark_chain, '-j', 'MARK',
+                    '--set-mark', '1',
+                    '--dest', '%s/%s' % (snet, swidth),
+                    '-m', 'tcp', '-p', 'tcp')
+                ipt('-A', tproxy_chain, '-j', 'TPROXY',
+                    '--tproxy-mark', '0x1/0x1',
+                    '--dest', '%s/%s' % (snet, swidth),
+                    '-m', 'tcp', '-p', 'tcp',
+                    '--on-port', str(port))
+
+            if sexclude and udp:
+                ipt('-A', mark_chain, '-j', 'RETURN',
+                    '--dest', '%s/%s' % (snet, swidth),
+                    '-m', 'udp', '-p', 'udp')
+                ipt('-A', tproxy_chain, '-j', 'RETURN',
+                    '--dest', '%s/%s' % (snet, swidth),
+                    '-m', 'udp', '-p', 'udp')
+            elif udp:
+                ipt('-A', mark_chain, '-j', 'MARK',
+                    '--set-mark', '1',
+                    '--dest', '%s/%s' % (snet, swidth),
+                    '-m', 'udp', '-p', 'udp')
+                ipt('-A', tproxy_chain, '-j', 'TPROXY',
+                    '--tproxy-mark', '0x1/0x1',
+                    '--dest', '%s/%s' % (snet, swidth),
+                    '-m', 'udp', '-p', 'udp',
+                    '--on-port', str(port))
+
+
+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,))
+
+
+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 False
+    oldval = _oldctls[name]
+    if val != oldval:
+        rv = _sysctl_set(name, val)
+        if rv == 0 and 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 True
+
+
+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], divertsock.family):
+            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)
+    debug1('>> %s\n' % ' '.join(argv))
+    rv = ssubprocess.call(argv)
+    if rv:
+        raise Fatal('%r returned %d' % (argv, rv))
+
+
+def do_ipfw(port, dnsport, family, subnets, udp):
+    # IPv6 not supported
+    if family not in [socket.AF_INET, ]:
+        raise Exception(
+            'Address family "%s" unsupported by ipfw method'
+            % family_to_string(family))
+    if udp:
+        raise Exception("UDP not supported by ipfw method")
+
+    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)
+        changed = sysctl_set('net.inet.ip.scopedroute', 0, permanent=True)
+        if changed:
+            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)
+
+        ipfw('add', sport, 'check-state', 'ip',
+             'from', 'any', 'to', 'any')
+
+    if subnets:
+        # create new subnet entries
+        for f, swidth, sexclude, snet \
+                in sorted(subnets, key=lambda s: s[1], 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 f, ip in filter(lambda i: i[0] == family, 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 pfctl(args, stdin = None):
+    argv = ['pfctl'] + list(args.split(" "))
+    debug1('>> %s\n' % ' '.join(argv))
+
+    p = ssubprocess.Popen(argv, stdin = ssubprocess.PIPE, 
+                                stdout = ssubprocess.PIPE, 
+                                stderr = ssubprocess.PIPE)
+    o = p.communicate(stdin)
+    if p.returncode:
+        raise Fatal('%r returned %d' % (argv, p.returncode))
+
+    return o
+
+_pf_context = {'started_by_sshuttle': False, 'Xtoken':''}
+
+def do_pf(port, dnsport, family, subnets, udp):
+    global _pf_started_by_sshuttle
+    tables = []
+    translating_rules = []
+    filtering_rules = []
+
+    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 f, swidth, sexclude, snet \
+                in sorted(subnets, key=lambda s: (s[1], s[2]), reverse=True):
+                    includes.append("%s%s/%s" % ("!" if sexclude else "", snet, swidth))
+
+        tables.append('table <forward_subnets> {%s}' % ','.join(includes))
+        translating_rules.append('rdr pass on lo0 proto tcp to <forward_subnets> -> 127.0.0.1 port %r' % port)
+        filtering_rules.append('pass out route-to lo0 inet proto tcp to <forward_subnets> keep state')
+
+        if dnsport:
+            nslist = resolvconf_nameservers()
+            tables.append('table <dns_servers> {%s}' % ','.join([ns[1] for ns in nslist]))
+            translating_rules.append('rdr pass on lo0 proto udp to <dns_servers> port 53 -> 127.0.0.1 port %r' % dnsport)
+            filtering_rules.append('pass out route-to lo0 inet proto udp to <dns_servers> port 53 keep state')
+
+        rules = '\n'.join(tables + translating_rules + filtering_rules) + '\n'
+
+        pf_status = pfctl('-s all')[0]
+        if not '\nrdr-anchor "sshuttle" all\n' in pf_status:
+            pf_add_anchor_rule(PF_RDR, "sshuttle")        
+        if not '\nanchor "sshuttle" all\n' in pf_status:
+            pf_add_anchor_rule(PF_PASS, "sshuttle")
+
+        pfctl('-a sshuttle -f /dev/stdin', rules)
+        if sys.platform == "darwin":
+            o = pfctl('-E')
+            _pf_context['Xtoken'] = re.search(r'Token : (.+)', o[1]).group(1)
+        elif 'INFO:\nStatus: Disabled' in pf_status: 
+            pfctl('-e')
+            _pf_context['started_by_sshuttle'] = True
+    else:
+        pfctl('-a sshuttle -F all')
+        if sys.platform == "darwin":
+            pfctl('-X %s' % _pf_context['Xtoken'])
+        elif _pf_context['started_by_sshuttle']:
+            pfctl('-d')
+
+
+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 are some classes and functions used to support pf in yosemite. 
+class pf_state_xport(Union):
+    _fields_ = [("port", c_uint16),
+                ("call_id", c_uint16),
+                ("spi", c_uint32)]
+
+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",)
+
+class pfioc_natlook(Structure):
+    _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)]
+
+pfioc_rule = c_char * 3104  # sizeof(struct pfioc_rule)
+
+pfioc_pooladdr = c_char * 1136 # sizeof(struct pfioc_pooladdr) 
+
+MAXPATHLEN = 1024
+
+DIOCNATLOOK = ((0x40000000L | 0x80000000L) | ((sizeof(pfioc_natlook) & 0x1fff) << 16) | ((ord('D')) << 8) | (23))
+DIOCCHANGERULE = ((0x40000000L | 0x80000000L) | ((sizeof(pfioc_rule) & 0x1fff) << 16) | ((ord('D')) << 8) | (26))
+DIOCBEGINADDRS = ((0x40000000L | 0x80000000L) | ((sizeof(pfioc_pooladdr) & 0x1fff) << 16) | ((ord('D')) << 8) | (51))
+
+PF_CHANGE_ADD_TAIL = 2
+PF_CHANGE_GET_TICKET = 6
+
+PF_PASS = 0
+PF_RDR = 8
+
+PF_OUT = 2
+
+_pf_fd = None
+
+def pf_get_dev():
+    global _pf_fd
+    if _pf_fd == None:
+        _pf_fd = os.open('/dev/pf', os.O_RDWR)
+
+    return _pf_fd
+
+def pf_query_nat(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]]
+    
+    length = 4 if family == socket.AF_INET else 16
+
+    pnl = pfioc_natlook()
+    pnl.proto = proto
+    pnl.direction = PF_OUT
+    pnl.af = family
+    memmove(addressof(pnl.saddr), socket.inet_pton(pnl.af, src_ip), length)
+    pnl.sxport.port = socket.htons(src_port)
+    memmove(addressof(pnl.daddr), socket.inet_pton(pnl.af, dst_ip), length)
+    pnl.dxport.port = socket.htons(dst_port)
+
+    ioctl(pf_get_dev(), DIOCNATLOOK, (c_char * sizeof(pnl)).from_address(addressof(pnl)))
+
+    ip = socket.inet_ntop(pnl.af, (c_char * length).from_address(addressof(pnl.rdaddr)))
+    port = socket.ntohs(pnl.rdxport.port)
+    return (ip, port)
+
+def pf_add_anchor_rule(type, name):
+    ACTION_OFFSET = 0
+    POOL_TICKET_OFFSET = 8
+    ANCHOR_CALL_OFFSET = 1040
+    RULE_ACTION_OFFSET = 3068
+
+    pr = pfioc_rule()
+    ppa = pfioc_pooladdr()
+
+    ioctl(pf_get_dev(), DIOCBEGINADDRS, ppa)
+
+    memmove(addressof(pr) + POOL_TICKET_OFFSET, ppa[4:8], 4)  #pool_ticket
+    memmove(addressof(pr) + ANCHOR_CALL_OFFSET, name, min(MAXPATHLEN, len(name)))  #anchor_call = name
+    memmove(addressof(pr) + RULE_ACTION_OFFSET, struct.pack('I', type), 4)  #rule.action = type
+
+    memmove(addressof(pr) + ACTION_OFFSET, struct.pack('I', PF_CHANGE_GET_TICKET), 4) #action = PF_CHANGE_GET_TICKET
+    ioctl(pf_get_dev(), DIOCCHANGERULE, pr)
+
+    memmove(addressof(pr) + ACTION_OFFSET, struct.pack('I', PF_CHANGE_ADD_TAIL), 4) #action = PF_CHANGE_ADD_TAIL
+    ioctl(pf_get_dev(), DIOCCHANGERULE, pr)
+
+
+# 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_v6, port_v4, dnsport_v6, dnsport_v4, method, udp, syslog):
+    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)
+
+    if os.getuid() != 0:
+        raise Fatal('you must be root (or enable su/sudo) to set the firewall')
+
+    if method == "auto":
+        if program_exists('ipfw'):
+            method = "ipfw"
+        elif program_exists('iptables'):
+            method = "nat"
+        elif program_exists('pfctl'):
+            method = "pf"
+        else:
+            raise Fatal("can't find either ipfw, iptables or pfctl; check your PATH")
+
+    if method == "nat":
+        do_it = do_iptables_nat
+    elif method == "tproxy":
+        do_it = do_iptables_tproxy
+    elif method == "ipfw":
+        do_it = do_ipfw
+    elif method == "pf":
+        do_it = do_pf
+    else:
+        raise Exception('Unknown method "%s"' % method)
+
+    # 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 method %s.\n' % method)
+    sys.stdout.write('READY %s\n' % method)
+    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:
+            (family, width, exclude, ip) = line.strip().split(',', 3)
+        except:
+            raise Fatal('firewall: expected route or GO but got %r' % line)
+        subnets.append((int(family), int(width), bool(int(exclude)), ip))
+
+    try:
+        if line:
+            debug1('firewall manager: starting transproxy.\n')
+
+            subnets_v6 = filter(lambda i: i[0] == socket.AF_INET6, subnets)
+            if port_v6:
+                do_wait = do_it(
+                    port_v6, dnsport_v6, socket.AF_INET6, subnets_v6, udp)
+            elif len(subnets_v6) > 0:
+                debug1("IPv6 subnets defined but IPv6 disabled\n")
+
+            subnets_v4 = filter(lambda i: i[0] == socket.AF_INET, subnets)
+            if port_v4:
+                do_wait = do_it(
+                    port_v4, dnsport_v4, socket.AF_INET, subnets_v4, udp)
+            elif len(subnets_v4) > 0:
+                debug1('IPv4 subnets defined but IPv4 disabled\n')
+
+            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_v6 or port_v4)
+            elif 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, e:
+                    sys.stdout.write('QUERY_PF_NAT_FAILURE %s\n' % e)
+
+                sys.stdout.flush()
+            elif line:
+                raise Fatal('expected EOF, got %r' % line)
+            else:
+                break
+    finally:
+        try:
+            debug1('firewall manager: undoing changes.\n')
+        except:
+            pass
+        if port_v6:
+            do_it(port_v6, 0, socket.AF_INET6, [], udp)
+        if port_v4:
+            do_it(port_v4, 0, socket.AF_INET, [], udp)
+        restore_etc_hosts(port_v6 or port_v4)

src/helpers.py

@@ -0,0 +1,91 @@
+import sys
+import socket
+import 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
+
+
+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':
+            if ':' in words[1]:
+                l.append((socket.AF_INET6, words[1]))
+            else:
+                l.append((socket.AF_INET, 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 (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:
+            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_to_string(family):
+    if family == socket.AF_INET6:
+        return "AF_INET6"
+    elif family == socket.AF_INET:
+        return "AF_INET"
+    else:
+        return str(family)

src/hostwatch.py

@@ -1,19 +1,29 @@
-import time, socket, re, select, errno
+import time
+import socket
+import re
+import select
+import errno
+import os
+import sys
 if not globals().get('skip_imports'):
     import compat.ssubprocess as ssubprocess
     import helpers
-    from helpers import *
+    from helpers import log, debug1, debug2, debug3
 
-POLL_TIME = 60*15
+POLL_TIME = 60 * 15
 NETSTAT_POLL_TIME = 30
-CACHEFILE=os.path.expanduser('~/.sshuttle.hosts')
+CACHEFILE = os.path.expanduser('~/.sshuttle.hosts')
 
 
 _nmb_ok = True
 _smb_ok = True
 hostnames = {}
 queue = {}
-null = open('/dev/null', 'rb+')
+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):
@@ -24,7 +34,7 @@ def write_host_cache():
     tmpname = '%s.%d.tmp' % (CACHEFILE, os.getpid())
     try:
         f = open(tmpname, 'wb')
-        for name,ip in sorted(hostnames.items()):
+        for name, ip in sorted(hostnames.items()):
             f.write('%s,%s\n' % (name, ip))
         f.close()
         os.rename(tmpname, CACHEFILE)
@@ -46,7 +56,7 @@ def read_host_cache():
     for line in f:
         words = line.strip().split(',')
         if len(words) == 2:
-            (name,ip) = words
+            (name, ip) = words
             name = re.sub(r'[^-\w]', '-', name).strip()
             ip = re.sub(r'[^0-9.]', '', ip).strip()
             if name and ip:
@@ -90,7 +100,7 @@ def _check_revdns(ip):
         debug3('<    %s\n' % r[0])
         check_host(r[0])
         found_host(r[0], ip)
-    except socket.herror, e:
+    except socket.herror:
         pass
 
 
@@ -101,7 +111,7 @@ def _check_dns(hostname):
         debug3('<    %s\n' % ip)
         check_host(ip)
         found_host(hostname, ip)
-    except socket.gaierror, e:
+    except socket.gaierror:
         pass
 
 
@@ -183,7 +193,7 @@ def _check_nmb(hostname, is_workgroup, is_master):
     global _nmb_ok
     if not _nmb_ok:
         return
-    argv = ['nmblookup'] + ['-M']*is_master + ['--', hostname]
+    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)
@@ -224,13 +234,13 @@ def check_workgroup(hostname):
 
 
 def _enqueue(op, *args):
-    t = (op,args)
-    if queue.get(t) == None:
+    t = (op, args)
+    if queue.get(t) is None:
         queue[t] = 0
 
 
 def _stdin_still_ok(timeout):
-    r,w,x = select.select([sys.stdin.fileno()], [], [], timeout)
+    r, w, x = select.select([sys.stdin.fileno()], [], [], timeout)
     if r:
         b = os.read(sys.stdin.fileno(), 4096)
         if not b:
@@ -257,8 +267,8 @@ def hw_main(seed_hosts):
 
     while 1:
         now = time.time()
-        for t,last_polled in queue.items():
-            (op,args) = t
+        for t, last_polled in queue.items():
+            (op, args) = t
             if not _stdin_still_ok(0):
                 break
             maxtime = POLL_TIME

src/main.py

@@ -0,0 +1,230 @@
+import sys
+import re
+import socket
+import helpers
+import options
+import client
+import server
+import firewall
+import hostwatch
+from helpers import 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)
+
+
+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
+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
+method=    auto, nat, tproxy, pf or ipfw
+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
+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
+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)
+"""
+o = options.Options(optspec)
+(opt, flags, extra) = o.parse(sys.argv[2:])
+
+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) != 6:
+            o.fatal('exactly six arguments expected')
+        sys.exit(firewall.main(int(extra[0]), int(extra[1]),
+                               int(extra[2]), int(extra[3]),
+                               extra[4], int(extra[5]), opt.syslog))
+    elif opt.hostwatch:
+        sys.exit(hostwatch.hw_main(extra))
+    else:
+        if len(extra) < 1 and not opt.auto_nets and not opt.subnets:
+            o.fatal('at least one subnet, subnet file, 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
+        if opt.subnets:
+            includes = parse_subnet_file(opt.subnets)
+        if not opt.method:
+            method = "auto"
+        elif opt.method in ["auto", "nat", "tproxy", "ipfw", "pf"]:
+            method = opt.method
+        else:
+            o.fatal("method %s not supported" % opt.method)
+        if not opt.listen:
+            if opt.method == "tproxy":
+                ipport_v6 = parse_ipport6('[::1]:0')
+            else:
+                ipport_v6 = None
+            ipport_v4 = parse_ipport4('127.0.0.1:0')
+        else:
+            ipport_v6 = None
+            ipport_v4 = None
+            list = opt.listen.split(",")
+            for ip in list:
+                if '[' in ip and ']' in ip and opt.method == "tproxy":
+                    ipport_v6 = parse_ipport6(ip)
+                else:
+                    ipport_v4 = parse_ipport4(ip)
+        return_code = client.main(ipport_v6, ipport_v4,
+                                  opt.ssh_cmd,
+                                  remotename,
+                                  opt.python,
+                                  opt.latency_control,
+                                  opt.dns,
+                                  method,
+                                  sh,
+                                  opt.auto_nets,
+                                  parse_subnets(includes),
+                                  parse_subnets(excludes),
+                                  opt.syslog, opt.daemon, opt.pidfile)
+
+        if return_code == 0:
+            log('Normal exit code, exiting...')
+        else:
+            log('Abnormal exit code detected, failing...' % return_code)
+        sys.exit(return_code)
+
+except Fatal, e:
+    log('fatal: %s\n' % e)
+    sys.exit(99)
+except KeyboardInterrupt:
+    log('\n')
+    log('Keyboard interrupt: exiting.\n')
+    sys.exit(1)

src/options.py

@@ -1,9 +1,16 @@
 """Command-line options parser.
 With the help of an options spec string, easily parse command-line options.
 """
-import sys, os, textwrap, getopt, re, struct
+import sys
+import os
+import textwrap
+import getopt
+import re
+import struct
+
 
 class OptDict:
+
     def __init__(self):
         self._opts = {}
 
@@ -46,24 +53,29 @@ def _atoi(v):
 def _remove_negative_kv(k, v):
     if k.startswith('no-') or k.startswith('no_'):
         return k[3:], not v
-    return k,v
+    return k, v
+
 
 def _remove_negative_k(k):
     return _remove_negative_kv(k, None)[0]
 
 
 def _tty_width():
+    if not hasattr(sys.stderr, "fileno"):
+        return _atoi(os.environ.get('WIDTH')) or 70
     s = struct.pack("HHHH", 0, 0, 0, 0)
     try:
-        import fcntl, termios
+        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
+    (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
@@ -76,9 +88,9 @@ class Options:
     By default, the parser function is getopt.gnu_getopt, and the abort
     behaviour is to exit the program.
     """
-    def __init__(self, exe, optspec, optfunc=getopt.gnu_getopt,
+
+    def __init__(self, optspec, optfunc=getopt.gnu_getopt,
                  onabort=_default_onabort):
-        self.exe = exe
         self.optspec = optspec
         self._onabort = onabort
         self.optfunc = optfunc
@@ -96,7 +108,8 @@ class Options:
         first_syn = True
         while lines:
             l = lines.pop()
-            if l == '--': break
+            if l == '--':
+                break
             out.append('%s: %s\n' % (first_syn and 'usage' or '   or', l))
             first_syn = False
         out.append('\n')
@@ -122,8 +135,8 @@ class Options:
                     defval = None
                 flagl = flags.split(',')
                 flagl_nice = []
-                for f in flagl:
-                    f,dvi = _remove_negative_kv(f, _intify(defval))
+                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
@@ -135,14 +148,14 @@ class Options:
                         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)
+                        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))
+                                                  subsequent_indent=' ' * 28))
                 out.append(argtext + '\n')
                 last_was_option = True
             else:
@@ -171,17 +184,18 @@ class Options:
         and "extra" is a list of positional arguments.
         """
         try:
-            (flags,extra) = self.optfunc(args, self._shortopts, self._longopts)
+            (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():
+        for k, v in self._defaults.iteritems():
             k = self._aliases[k]
             opt[k] = v
 
-        for (k,v) in flags:
+        for (k, v) in flags:
             k = k.lstrip('-')
             if k in ('h', '?', 'help'):
                 self.usage()
@@ -196,6 +210,6 @@ class Options:
                 else:
                     v = _intify(v)
             opt[k] = v
-        for (f1,f2) in self._aliases.iteritems():
+        for (f1, f2) in self._aliases.iteritems():
             opt[f1] = opt._opts.get(f2)
-        return (opt,flags,extra)
+        return (opt, flags, extra)

src/server.py

@@ -0,0 +1,335 @@
+import re
+import struct
+import socket
+import traceback
+import time
+import sys
+import os
+if not globals().get('skip_imports'):
+    import ssnet
+    import helpers
+    import hostwatch
+    import compat.ssubprocess as ssubprocess
+    from ssnet import Handler, Proxy, Mux, MuxWrapper
+    from helpers import log, debug1, debug2, debug3, Fatal, \
+        resolvconf_random_nameserver
+
+
+if not globals().get('latency_control'):
+    latency_control = None
+
+
+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] 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):
+    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):
+    return n * int(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.AF_INET, 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():
+    for (family, ip, width) in _list_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):
+    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:
+                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):
+        # FIXME! IPv4 specific
+        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
+        # FIXME! IPv4 specific
+        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
+        # FIXME! Support IPv6 nameservers
+        self.peer = resolvconf_random_nameserver()[1]
+        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
+
+
+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
+        if family == socket.AF_INET:
+            self.sock.setsockopt(socket.SOL_IP, socket.IP_TTL, 42)
+
+    def send(self, dstip, data):
+        debug2('UDP: sending to %r port %d\n' % dstip)
+        try:
+            self.sock.sendto(data, dstip)
+        except socket.error, e:
+            log('UDP send to %r port %d: %s\n' % (dstip[0], dstip[1], e))
+            return
+
+    def callback(self):
+        try:
+            data, peer = self.sock.recvfrom(4096)
+        except socket.error, e:
+            log('UDP recv from %r port %d: %s\n' % (peer[0], peer[1], e))
+            return
+        debug2('UDP response: %d bytes\n' % len(data))
+        hdr = "%s,%r," % (peer[0], peer[1])
+        self.mux.send(self.chan, ssnet.CMD_UDP_DATA, hdr + data)
+
+
+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('  %d/%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 += '%d,%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):
+        (family, dstip, dstport) = data.split(',', 2)
+        family = int(family)
+        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.\n' % channel)
+        h = DnsProxy(mux, channel, data)
+        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\n' % (channel, cmd))
+        if cmd == ssnet.CMD_UDP_DATA:
+            (dstip, dstport, data) = data.split(",", 2)
+            dstport = int(dstport)
+            debug2('is incoming UDP data. %r %d.\n' % (dstip, dstport))
+            h = udphandlers[channel]
+            h.send((dstip, dstport), data)
+        elif cmd == ssnet.CMD_UDP_CLOSE:
+            debug2('is incoming UDP close\n')
+            h = udphandlers[channel]
+            h.ok = False
+            del mux.channels[channel]
+
+    def udp_open(channel, data):
+        debug2('Incoming UDP open.\n')
+        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\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:
+                    debug3('expiring dnsreqs channel=%d\n' % channel)
+                    del dnshandlers[channel]
+                    h.ok = False
+        if udphandlers:
+            for channel, h in udphandlers.items():
+                if not h.ok:
+                    debug3('expiring UDP channel=%d\n' % channel)
+                    del udphandlers[channel]
+                    h.ok = False

src/ssh.py

@@ -1,7 +1,11 @@
-import sys, os, re, socket, zlib
+import sys
+import os
+import re
+import socket
+import zlib
 import compat.ssubprocess as ssubprocess
 import helpers
-from helpers import *
+from helpers import debug2
 
 
 def readfile(name):
@@ -14,20 +18,19 @@ def readfile(name):
     raise Exception("can't find file %r in any of %r" % (name, path))
 
 
-def empackage(z, filename):
-    (path,basename) = os.path.split(filename)
-    content = z.compress(readfile(filename))
+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)
+    return '%s\n%d\n%s' % (basename, len(content), content)
 
 
-def connect(ssh_cmd, rhostport, python, stderr):
-    main_exe = sys.argv[0]
+def connect(ssh_cmd, rhostport, python, stderr, options):
     portl = []
 
-    rhostIsIPv6 = False
     if (rhostport or '').count(':') > 1:
-        rhostIsIPv6 = True
         if rhostport.count(']') or rhostport.count('['):
             result = rhostport.split(']')
             rhost = result[0].strip('[')
@@ -35,7 +38,9 @@ def connect(ssh_cmd, rhostport, python, stderr):
                 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.
+        # can't disambiguate IPv6 colons and a port number. pass the hostname
+        # through.
+        else:
             rhost = rhostport
     else:  # IPv4
         l = (rhostport or '').split(':', 1)
@@ -46,13 +51,11 @@ def connect(ssh_cmd, rhostport, python, stderr):
     if rhost == '-':
         rhost = None
 
-    ipv6flag = []
-    if rhostIsIPv6:
-        ipv6flag = ['-6']
-
     z = zlib.compressobj(1)
     content = readfile('assembler.py')
-    content2 = (empackage(z, 'helpers.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') +
@@ -67,23 +70,29 @@ def connect(ssh_cmd, rhostport, python, stderr):
                 """ % (helpers.verbose or 0, len(content))
     pyscript = re.sub(r'\s+', ' ', pyscript.strip())
 
-        
     if not rhost:
-        argv = [python, '-c', pyscript]
+        # 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, '--', "'%s' -c '%s'" % (python, pyscript)])
-    (s1,s2) = socket.socketpair()
+                [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())
+    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,

src/sshuttle

@@ -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

src/sshuttle.md

@@ -1,6 +1,6 @@
-% sshuttle(8) Sshuttle 0.44
+% sshuttle(8) Sshuttle 0.46
 % Avery Pennarun <apenwarr@gmail.com>
-% 2010-12-31
+% 2011-01-25
 
 # NAME
 
@@ -71,6 +71,10 @@ entire subnet to the VPN.
     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
@@ -90,6 +94,10 @@ entire subnet to the VPN.
     `0/0 -x 1.2.3.0/24` to forward everything except the
     local subnet over the VPN, for example.
 
+-X, --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
@@ -109,6 +117,22 @@ entire subnet to the VPN.
     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`.
@@ -237,7 +261,24 @@ 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.
+
+On MacOS, sshuttle will set the kernel boot flag
+net.inet.ip.scopedroute to 0, which interferes with OS X
+Internet Sharing and some VPN clients. To reset this flag,
+you can remove any reference to net.inet.ip.scopedroute from
+/Library/Preferences/SystemConfiguration/com.apple.Boot.plist
+and reboot.
+
+
 # SEE ALSO
 
 `ssh`(1), `python`(1)
-

src/ssnet.py

@@ -1,6 +1,12 @@
-import struct, socket, errno, select
+import struct
+import socket
+import errno
+import select
+import os
 if not globals().get('skip_imports'):
-    from helpers import *
+    from helpers import log, debug1, debug2, debug3, Fatal
+
+MAX_CHANNEL = 65535
 
 # these don't exist in the socket module in python 2.3!
 SHUT_RD = 0
@@ -14,28 +20,42 @@ HDR_LEN = 8
 CMD_EXIT = 0x4200
 CMD_PING = 0x4201
 CMD_PONG = 0x4202
-CMD_CONNECT = 0x4203
-CMD_STOP_SENDING = 0x4204
-CMD_EOF = 0x4205
-CMD_DATA = 0x4206
+CMD_TCP_CONNECT = 0x4203
+CMD_TCP_STOP_SENDING = 0x4204
+CMD_TCP_EOF = 0x4205
+CMD_TCP_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_CONNECT: 'CONNECT',
-    CMD_STOP_SENDING: 'STOP_SENDING',
-    CMD_EOF: 'EOF',
-    CMD_DATA: 'DATA',
+    CMD_TCP_CONNECT: 'TCP_CONNECT',
+    CMD_TCP_STOP_SENDING: 'TCP_STOP_SENDING',
+    CMD_TCP_EOF: 'TCP_EOF',
+    CMD_TCP_DATA: 'TCP_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]
+
 
 def _add(l, elem):
     if not elem in l:
@@ -76,11 +96,14 @@ def _try_peername(sock):
 
 
 _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\n)' % _swcount)
+        debug3('creating new SockWrapper (%d now exist)\n' % _swcount)
         self.exc = None
         self.rsock = rsock
         self.wsock = wsock
@@ -95,7 +118,7 @@ class SockWrapper:
         _swcount -= 1
         debug1('%r: deleting (%d remain)\n' % (self, _swcount))
         if self.exc:
-            debug1('%r: error was: %r\n' % (self, self.exc))
+            debug1('%r: error was: %s\n' % (self, self.exc))
 
     def __repr__(self):
         if self.rsock == self.wsock:
@@ -123,15 +146,34 @@ class SockWrapper:
             # connected successfully (Linux)
             self.connect_to = None
         except socket.error, e:
-            debug3('%r: connect result: %r\n' % (self, e))
+            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
+                # that is now connected but returned EINPROGRESS last time,
+                # on BSD, on python pre-2.5.1.  We need to use getsockopt()
+                # to get the "real" error.  Later pythons do this
+                # automatically, so this code won't run.
+                realerr = self.rsock.getsockopt(socket.SOL_SOCKET,
+                                                socket.SO_ERROR)
+                e = socket.error(realerr, os.strerror(realerr))
+                debug3('%r: fixed connect result: %s\n' % (self, e))
             if e.args[0] in [errno.EINPROGRESS, errno.EALREADY]:
                 pass  # not connected yet
+            elif e.args[0] == 0:
+                # connected successfully (weird Linux bug?)
+                # Sometimes Linux seems to return EINVAL when it isn't
+                # invalid.  This *may* be caused by a race condition
+                # between connect() and getsockopt(SO_ERROR) (ie. it
+                # finishes connecting in between the two, so there is no
+                # longer an error).  However, I'm not sure of that.
+                #
+                # 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)
                 self.connect_to = None
-            elif e.args[0] in [errno.ECONNREFUSED, errno.ETIMEDOUT,
-                               errno.EHOSTUNREACH, errno.ENETUNREACH,
-                               errno.EACCES, errno.EPERM]:
+            elif e.args[0] in NET_ERRS + [errno.EACCES, errno.EPERM]:
                 # a "normal" kind of error
                 self.connect_to = None
                 self.seterr(e)
@@ -142,7 +184,7 @@ class SockWrapper:
         if not self.shut_read:
             debug2('%r: done reading\n' % self)
             self.shut_read = True
-            #self.rsock.shutdown(SHUT_RD)  # doesn't do anything anyway
+            # self.rsock.shutdown(SHUT_RD)  # doesn't do anything anyway
 
     def nowrite(self):
         if not self.shut_write:
@@ -208,7 +250,8 @@ 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:
@@ -220,7 +263,7 @@ class Handler:
 
     def callback(self):
         log('--no callback defined-- %r\n' % self)
-        (r,w,x) = select.select(self.socks, [], [], 0)
+        (r, w, x) = select.select(self.socks, [], [], 0)
         for s in r:
             v = s.recv(4096)
             if not v:
@@ -230,6 +273,7 @@ class Handler:
 
 
 class Proxy(Handler):
+
     def __init__(self, wrap1, wrap2):
         Handler.__init__(self, [wrap1.rsock, wrap1.wsock,
                                 wrap2.rsock, wrap2.wsock])
@@ -237,8 +281,10 @@ class Proxy(Handler):
         self.wrap2 = wrap2
 
     def pre_select(self, r, w, x):
-        if self.wrap1.shut_write: self.wrap2.noread()
-        if self.wrap2.shut_write: self.wrap1.noread()
+        if self.wrap1.shut_write:
+            self.wrap2.noread()
+        if self.wrap2.shut_write:
+            self.wrap1.noread()
 
         if self.wrap1.connect_to:
             _add(w, self.wrap1.rsock)
@@ -277,11 +323,13 @@ class Proxy(Handler):
 
 
 class Mux(Handler):
+
     def __init__(self, rsock, wsock):
         Handler.__init__(self, [rsock, wsock])
         self.rsock = rsock
         self.wsock = wsock
-        self.new_channel = self.got_routes = None
+        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
@@ -296,7 +344,7 @@ class Mux(Handler):
         # channel 0 is special, so we never allocate it
         for timeout in xrange(1024):
             self.chani += 1
-            if self.chani > 65535:
+            if self.chani > MAX_CHANNEL:
                 self.chani = 1
             if not self.channels.get(self.chani):
                 return self.chani
@@ -313,7 +361,7 @@ class Mux(Handler):
                 self.send(0, CMD_PING, 'rttest')
             self.too_full = True
         #ob = []
-        #for b in self.outbuf:
+        # 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))
@@ -324,13 +372,13 @@ class Mux(Handler):
         p = struct.pack('!ccHHH', 'S', '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)),
+               % (channel, cmd_to_name.get(cmd, hex(cmd)),
                   len(data), self.fullness))
         self.fullness += len(data)
 
     def got_packet(self, channel, cmd, data):
         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)))
         if cmd == CMD_PING:
             self.send(0, CMD_PONG, data)
         elif cmd == CMD_PONG:
@@ -339,10 +387,18 @@ class Mux(Handler):
             self.fullness = 0
         elif cmd == CMD_EXIT:
             self.ok = False
-        elif cmd == CMD_CONNECT:
+        elif cmd == CMD_TCP_CONNECT:
             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))
+            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)
@@ -362,7 +418,7 @@ class Mux(Handler):
             callback = self.channels.get(channel)
             if not callback:
                 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)
 
@@ -390,11 +446,11 @@ class Mux(Handler):
 
     def handle(self):
         self.fill()
-        #log('inbuf is: (%d,%d) %r\n'
+        # 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 == 'S')
                 assert(s2 == 'S')
@@ -413,7 +469,7 @@ class Mux(Handler):
             _add(w, self.wsock)
 
     def callback(self):
-        (r,w,x) = select.select([self.rsock], [self.wsock], [], 0)
+        (r, w, x) = select.select([self.rsock], [self.wsock], [], 0)
         if self.rsock in r:
             self.handle()
         if self.outbuf and self.wsock in w:
@@ -421,6 +477,7 @@ class Mux(Handler):
 
 
 class MuxWrapper(SockWrapper):
+
     def __init__(self, mux, channel):
         SockWrapper.__init__(self, mux.rsock, mux.wsock)
         self.mux = mux
@@ -434,18 +491,18 @@ class MuxWrapper(SockWrapper):
         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.shut_read = True
-            self.mux.send(self.channel, CMD_STOP_SENDING, '')
+            self.mux.send(self.channel, CMD_TCP_STOP_SENDING, '')
             self.maybe_close()
 
     def nowrite(self):
         if not self.shut_write:
             self.shut_write = True
-            self.mux.send(self.channel, CMD_EOF, '')
+            self.mux.send(self.channel, CMD_TCP_EOF, '')
             self.maybe_close()
 
     def maybe_close(self):
@@ -462,7 +519,7 @@ class MuxWrapper(SockWrapper):
             return 0  # too much already enqueued
         if len(buf) > 2048:
             buf = buf[:2048]
-        self.mux.send(self.channel, CMD_DATA, buf)
+        self.mux.send(self.channel, CMD_TCP_DATA, buf)
         return len(buf)
 
     def uread(self):
@@ -472,24 +529,24 @@ class MuxWrapper(SockWrapper):
             return None  # no data available right now
 
     def got_packet(self, cmd, data):
-        if cmd == CMD_EOF:
+        if cmd == CMD_TCP_EOF:
             self.noread()
-        elif cmd == CMD_STOP_SENDING:
+        elif cmd == CMD_TCP_STOP_SENDING:
             self.nowrite()
-        elif cmd == CMD_DATA:
+        elif cmd == CMD_TCP_DATA:
             self.buf.append(data)
         else:
             raise Exception('unknown command %d (%d bytes)'
                             % (cmd, len(data)))
 
 
-def connect_dst(ip, port):
+def connect_dst(family, ip, port):
     debug2('Connecting to %s:%d\n' % (ip, port))
-    outsock = socket.socket()
+    outsock = socket.socket(family)
     outsock.setsockopt(socket.SOL_IP, socket.IP_TTL, 42)
     return SockWrapper(outsock, outsock,
-                       connect_to = (ip,port),
-                       peername = '%s:%d' % (ip,port))
+                       connect_to=(ip, port),
+                       peername = '%s:%d' % (ip, port))
 
 
 def runonce(handlers, mux):
@@ -501,14 +558,14 @@ def runonce(handlers, mux):
         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)\n'
            % (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\n'
            % (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:

src/ssyslog.py

@@ -1,8 +1,11 @@
-import sys, os
+import sys
+import os
 from compat import ssubprocess
 
 
 _p = None
+
+
 def start_syslog():
     global _p
     _p = ssubprocess.Popen(['logger',

src/stresstest.py

@@ -0,0 +1,89 @@
+#!/usr/bin/env python
+import socket
+import select
+import struct
+import 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()

src/ui-macos/.gitignore

@@ -0,0 +1,8 @@
+*.pyc
+*~
+/*.nib
+/debug.app
+/sources.list
+/Sshuttle VPN.app
+/*.tar.gz
+/*.zip

src/ui-macos/Info.plist

@@ -0,0 +1,40 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>English</string>
+	<key>CFBundleDisplayName</key>
+	<string>Sshuttle VPN</string>
+	<key>CFBundleExecutable</key>
+	<string>Sshuttle</string>
+	<key>CFBundleIconFile</key>
+	<string>app.icns</string>
+	<key>CFBundleIdentifier</key>
+	<string>ca.apenwarr.Sshuttle</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundleName</key>
+	<string>Sshuttle VPN</string>
+	<key>CFBundlePackageType</key>
+	<string>APPL</string>
+	<key>CFBundleShortVersionString</key>
+	<string>0.0.0</string>
+	<key>CFBundleSignature</key>
+	<string>????</string>
+	<key>CFBundleVersion</key>
+	<string>0.0.0</string>
+	<key>LSUIElement</key>
+	<string>1</string>
+	<key>LSHasLocalizedDisplayName</key>
+	<false/>
+	<key>NSAppleScriptEnabled</key>
+	<false/>
+	<key>NSHumanReadableCopyright</key>
+	<string>GNU LGPL Version 2</string>
+	<key>NSMainNibFile</key>
+	<string>MainMenu</string>
+	<key>NSPrincipalClass</key>
+	<string>NSApplication</string>
+</dict>
+</plist>

src/ui-macos/UserDefaults.plist

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>startAtLogin</key>
+	<false/>
+	<key>autoReconnect</key>
+	<true/>
+</dict>
+</plist>

src/ui-macos/all.do

@@ -0,0 +1 @@
+redo-ifchange debug.app dist

src/ui-macos/askpass.py

@@ -0,0 +1,30 @@
+import re
+import subprocess
+
+
+def askpass(prompt):
+    prompt = prompt.replace('"', "'")
+
+    if 'yes/no' in prompt:
+        return "yes"
+
+    script = """
+        tell application "Finder"
+            activate
+            display dialog "%s" \
+              with title "Sshuttle SSH Connection" \
+              default answer "" \
+              with icon caution \
+              with hidden answer
+        end tell
+    """ % prompt
+
+    p = subprocess.Popen(['osascript', '-e', script], stdout=subprocess.PIPE)
+    out = p.stdout.read()
+    rv = p.wait()
+    if rv:
+        return None
+    g = re.match("text returned:(.*), button returned:.*", out)
+    if not g:
+        return None
+    return g.group(1)

src/ui-macos/bits/.gitignore

@@ -0,0 +1 @@
+/runpython

src/ui-macos/bits/PkgInfo

@@ -0,0 +1 @@
+APPL????

src/ui-macos/bits/runpython.c

@@ -0,0 +1,23 @@
+/*
+ * This rather pointless program acts like the python interpreter, except
+ * it's intended to sit inside a MacOS .app package, so that its argv[0]
+ * will point inside the package.
+ *
+ * NSApplicationMain() looks for Info.plist using the path in argv[0], which
+ * goes wrong if your interpreter is /usr/bin/python.
+ */
+#include <Python/Python.h>
+#include <string.h>
+#include <unistd.h>
+
+int main(int argc, char **argv)
+{
+    char *path = strdup(argv[0]), *cptr;
+    char *args[] = {argv[0], "../Resources/main.py", NULL};
+    cptr = strrchr(path, '/');
+    if (cptr)
+	*cptr = 0;
+    chdir(path);
+    free(path);
+    return Py_Main(2, args);
+}

src/ui-macos/bits/runpython.do

@@ -0,0 +1,20 @@
+exec >&2
+redo-ifchange runpython.c
+ARCHES=""
+printf "Platforms: "
+if [ -d /usr/libexec/gcc/darwin ]; then
+    for d in /usr/libexec/gcc/darwin/*; do
+        PLAT=$(basename "$d")
+        [ "$PLAT" != "ppc64" ] || continue  # fails for some reason on my Mac
+        ARCHES="$ARCHES -arch $PLAT"
+        printf "$PLAT "
+    done
+fi
+printf "\n"
+PYTHON_LDFLAGS=$(python-config --ldflags)
+PYTHON_INCLUDES=$(python-config --includes)
+gcc $ARCHES \
+    -Wall -o $3 runpython.c \
+    $PYTHON_INCLUDES \
+    $PYTHON_LDFLAGS \
+    -framework Python

src/ui-macos/clean.do

@@ -0,0 +1,4 @@
+exec >&2
+find . -name '*~' | xargs rm -f
+rm -rf *.app *.zip *.tar.gz
+rm -f bits/runpython *.nib sources.list

src/ui-macos/debug.app.do

@@ -0,0 +1,15 @@
+redo-ifchange bits/runpython MainMenu.nib
+rm -rf debug.app
+mkdir debug.app debug.app/Contents
+cd debug.app/Contents
+ln -s ../.. Resources
+ln -s ../.. English.lproj
+ln -s ../../Info.plist .
+ln -s ../../app.icns .
+
+mkdir MacOS
+cd MacOS
+ln -s ../../../bits/runpython Sshuttle
+
+cd ../../..
+redo-ifchange $(find debug.app -type f)

src/ui-macos/default.app.do

@@ -0,0 +1,28 @@
+TOP=$PWD
+redo-ifchange sources.list
+redo-ifchange Info.plist bits/runpython \
+	$(while read name newname; do echo "$name"; done <sources.list)
+
+rm -rf "$2.app"
+mkdir "$2.app" "$2.app/Contents"
+cd "$2.app/Contents"
+
+cp "$TOP/Info.plist" .
+
+mkdir MacOS
+cp "$TOP/bits/runpython" MacOS/Sshuttle
+
+mkdir Resources
+
+cd "$TOP"
+while read name newname; do
+	[ -z "$name" ] && continue
+	: "${newname:=$name}"
+	outname=$2.app/Contents/Resources/$newname
+	outdir=$(dirname "$outname")
+	[ -d "$outdir" ] || mkdir "$outdir"
+	cp "${name-$newname}" "$outname"
+done <sources.list
+
+cd "$2.app"
+redo-ifchange $(find . -type f)

src/ui-macos/default.app.tar.gz.do

@@ -0,0 +1,5 @@
+exec >&2
+IFS="
+"
+redo-ifchange $2.app
+tar -czf $3 $2.app/

src/ui-macos/default.app.zip.do

@@ -0,0 +1,5 @@
+exec >&2
+IFS="
+"
+redo-ifchange $2.app
+zip -q -r $3 $2.app/

src/ui-macos/default.nib.do

@@ -0,0 +1,2 @@
+redo-ifchange $2.xib
+ibtool --compile $3 $2.xib

src/ui-macos/dist.do

@@ -0,0 +1 @@
+redo-ifchange "Sshuttle VPN.app.zip" "Sshuttle VPN.app.tar.gz"

src/ui-macos/git-export.do

@@ -0,0 +1,19 @@
+# update a local branch with pregenerated output files, so people can download
+# the completed tarballs from github.  Since we don't have any real binaries,
+# our final distribution package contains mostly blobs from the source code,
+# so this doesn't cost us much extra space in the repo.
+BRANCH=dist/macos
+redo-ifchange 'Sshuttle VPN.app'
+git update-ref refs/heads/$BRANCH origin/$BRANCH '' 2>/dev/null || true
+
+export GIT_INDEX_FILE=$PWD/gitindex.tmp
+rm -f "$GIT_INDEX_FILE"
+git add -f 'Sshuttle VPN.app'
+
+MSG="MacOS precompiled app package for $(git describe)"
+TREE=$(git write-tree --prefix=ui-macos)
+git show-ref refs/heads/$BRANCH >/dev/null && PARENT="-p refs/heads/$BRANCH"
+COMMITID=$(echo "$MSG" | git commit-tree $TREE $PARENT)
+
+git update-ref refs/heads/$BRANCH $COMMITID
+rm -f "$GIT_INDEX_FILE"

src/ui-macos/main.py

@@ -0,0 +1,401 @@
+import sys
+import os
+import pty
+from AppKit import (
+  objc,
+  NSApp,
+  NSApplicationMain,
+  NSAttributedString,
+  NSFileHandle,
+  NSFileHandleDataAvailableNotification,
+  NSImage,
+  NSMenu,
+  NSMenuItem,
+  NSNotificationCenter,
+  NSObject,
+  NSStatusBar,
+  NSVariableStatusItemLength,
+)
+import my
+import models
+import askpass
+
+
+def sshuttle_args(host, auto_nets, auto_hosts, dns, nets, debug,
+                  no_latency_control):
+    argv = [my.bundle_path('sshuttle/sshuttle', ''), '-r', host]
+    assert(argv[0])
+    if debug:
+        argv.append('-v')
+    if auto_nets:
+        argv.append('--auto-nets')
+    if auto_hosts:
+        argv.append('--auto-hosts')
+    if dns:
+        argv.append('--dns')
+    if no_latency_control:
+        argv.append('--no-latency-control')
+    argv += nets
+    return argv
+
+
+class _Callback(NSObject):
+
+    def initWithFunc_(self, func):
+        self = super(_Callback, self).init()
+        self.func = func
+        return self
+
+    def func_(self, obj):
+        return self.func(obj)
+
+
+class Callback:
+
+    def __init__(self, func):
+        self.obj = _Callback.alloc().initWithFunc_(func)
+        self.sel = self.obj.func_
+
+
+class Runner:
+
+    def __init__(self, argv, logfunc, promptfunc, serverobj):
+        print 'in __init__'
+        self.id = argv
+        self.rv = None
+        self.pid = None
+        self.fd = None
+        self.logfunc = logfunc
+        self.promptfunc = promptfunc
+        self.serverobj = serverobj
+        self.buf = ''
+        self.logfunc('\nConnecting to %s.\n' % self.serverobj.host())
+        print 'will run: %r' % argv
+        self.serverobj.setConnected_(False)
+        pid, fd = pty.fork()
+        if pid == 0:
+            # child
+            try:
+                os.execvp(argv[0], argv)
+            except Exception, e:
+                sys.stderr.write('failed to start: %r\n' % e)
+                raise
+            finally:
+                os._exit(42)
+        # parent
+        self.pid = pid
+        self.file = NSFileHandle.alloc()\
+            .initWithFileDescriptor_closeOnDealloc_(fd, True)
+        self.cb = Callback(self.gotdata)
+        NSNotificationCenter.defaultCenter()\
+            .addObserver_selector_name_object_(
+                self.cb.obj, self.cb.sel,
+                NSFileHandleDataAvailableNotification, self.file)
+        self.file.waitForDataInBackgroundAndNotify()
+
+    def __del__(self):
+        self.wait()
+
+    def _try_wait(self, options):
+        if self.rv is None and self.pid > 0:
+            pid, code = os.waitpid(self.pid, options)
+            if pid == self.pid:
+                if os.WIFEXITED(code):
+                    self.rv = os.WEXITSTATUS(code)
+                else:
+                    self.rv = -os.WSTOPSIG(code)
+                self.serverobj.setConnected_(False)
+                self.serverobj.setError_('VPN process died')
+                self.logfunc('Disconnected.\n')
+        print 'wait_result: %r' % self.rv
+        return self.rv
+
+    def wait(self):
+        rv = None
+        while rv is None:
+            self.gotdata(None)
+            rv = self._try_wait(os.WNOHANG)
+
+    def poll(self):
+        return self._try_wait(os.WNOHANG)
+
+    def kill(self):
+        assert(self.pid > 0)
+        print 'killing: pid=%r rv=%r' % (self.pid, self.rv)
+        if self.rv is None:
+            self.logfunc('Disconnecting from %s.\n' % self.serverobj.host())
+            os.kill(self.pid, 15)
+            self.wait()
+
+    def gotdata(self, notification):
+        print 'gotdata!'
+        d = str(self.file.availableData())
+        if d:
+            self.logfunc(d)
+            self.buf = self.buf + d
+            if 'Connected.\r\n' in self.buf:
+                self.serverobj.setConnected_(True)
+            self.buf = self.buf[-4096:]
+            if self.buf.strip().endswith(':'):
+                lastline = self.buf.rstrip().split('\n')[-1]
+                resp = self.promptfunc(lastline)
+                add = ' (response)\n'
+                self.buf += add
+                self.logfunc(add)
+                self.file.writeData_(my.Data(resp + '\n'))
+            self.file.waitForDataInBackgroundAndNotify()
+        self.poll()
+        # print 'gotdata done!'
+
+
+class SshuttleApp(NSObject):
+
+    def initialize(self):
+        d = my.PList('UserDefaults')
+        my.Defaults().registerDefaults_(d)
+
+
+class SshuttleController(NSObject):
+    # Interface builder outlets
+    startAtLoginField = objc.IBOutlet()
+    autoReconnectField = objc.IBOutlet()
+    debugField = objc.IBOutlet()
+    routingField = objc.IBOutlet()
+    prefsWindow = objc.IBOutlet()
+    serversController = objc.IBOutlet()
+    logField = objc.IBOutlet()
+    latencyControlField = objc.IBOutlet()
+
+    servers = []
+    conns = {}
+
+    def _connect(self, server):
+        host = server.host()
+        print 'connecting %r' % host
+        self.fill_menu()
+
+        def logfunc(msg):
+            print 'log! (%d bytes)' % len(msg)
+            self.logField.textStorage()\
+                .appendAttributedString_(NSAttributedString.alloc()
+                                         .initWithString_(msg))
+            self.logField.didChangeText()
+
+        def promptfunc(prompt):
+            print 'prompt! %r' % prompt
+            return askpass.askpass(prompt)
+        nets_mode = server.autoNets()
+        if nets_mode == models.NET_MANUAL:
+            manual_nets = ["%s/%d" % (i.subnet(), i.width())
+                           for i in server.nets()]
+        elif nets_mode == models.NET_ALL:
+            manual_nets = ['0/0']
+        else:
+            manual_nets = []
+        noLatencyControl = (server.latencyControl() != models.LAT_INTERACTIVE)
+        conn = Runner(sshuttle_args(host,
+                                    auto_nets=nets_mode == models.NET_AUTO,
+                                    auto_hosts=server.autoHosts(),
+                                    dns=server.useDns(),
+                                    nets=manual_nets,
+                                    debug=self.debugField.state(),
+                                    no_latency_control=noLatencyControl),
+                      logfunc=logfunc, promptfunc=promptfunc,
+                      serverobj=server)
+        self.conns[host] = conn
+
+    def _disconnect(self, server):
+        host = server.host()
+        print 'disconnecting %r' % host
+        conn = self.conns.get(host)
+        if conn:
+            conn.kill()
+        self.fill_menu()
+        self.logField.textStorage().setAttributedString_(
+            NSAttributedString.alloc().initWithString_(''))
+
+    @objc.IBAction
+    def cmd_connect(self, sender):
+        server = sender.representedObject()
+        server.setWantConnect_(True)
+
+    @objc.IBAction
+    def cmd_disconnect(self, sender):
+        server = sender.representedObject()
+        server.setWantConnect_(False)
+
+    @objc.IBAction
+    def cmd_show(self, sender):
+        self.prefsWindow.makeKeyAndOrderFront_(self)
+        NSApp.activateIgnoringOtherApps_(True)
+
+    @objc.IBAction
+    def cmd_quit(self, sender):
+        NSStatusBar.systemStatusBar().removeStatusItem_(self.statusitem)
+        NSApp.performSelector_withObject_afterDelay_(NSApp.terminate_,
+                                                     None, 0.0)
+
+    def fill_menu(self):
+        menu = self.menu
+        menu.removeAllItems()
+
+        def additem(name, func, obj):
+            it = menu.addItemWithTitle_action_keyEquivalent_(name, None, "")
+            it.setRepresentedObject_(obj)
+            it.setTarget_(self)
+            it.setAction_(func)
+
+        def addnote(name):
+            additem(name, None, None)
+
+        any_inprogress = None
+        any_conn = None
+        any_err = None
+        if len(self.servers):
+            for i in self.servers:
+                host = i.host()
+                title = i.title()
+                want = i.wantConnect()
+                connected = i.connected()
+                numnets = len(list(i.nets()))
+                if not host:
+                    additem('Connect Untitled', None, i)
+                elif i.autoNets() == models.NET_MANUAL and not numnets:
+                    additem('Connect %s (no routes)' % host, None, i)
+                elif want:
+                    any_conn = i
+                    additem('Disconnect %s' % title, self.cmd_disconnect, i)
+                else:
+                    additem('Connect %s' % title, self.cmd_connect, i)
+                if not want:
+                    msg = 'Off'
+                elif i.error():
+                    msg = 'ERROR - try reconnecting'
+                    any_err = i
+                elif connected:
+                    msg = 'Connected'
+                else:
+                    msg = 'Connecting...'
+                    any_inprogress = i
+                addnote('   State: %s' % msg)
+        else:
+            addnote('No servers defined yet')
+
+        menu.addItem_(NSMenuItem.separatorItem())
+        additem('Preferences...', self.cmd_show, None)
+        additem('Quit Sshuttle VPN', self.cmd_quit, None)
+
+        if any_err:
+            self.statusitem.setImage_(self.img_err)
+            self.statusitem.setTitle_('Error!')
+        elif any_conn:
+            self.statusitem.setImage_(self.img_running)
+            if any_inprogress:
+                self.statusitem.setTitle_('Connecting...')
+            else:
+                self.statusitem.setTitle_('')
+        else:
+            self.statusitem.setImage_(self.img_idle)
+            self.statusitem.setTitle_('')
+
+    def load_servers(self):
+        l = my.Defaults().arrayForKey_('servers') or []
+        sl = []
+        for s in l:
+            host = s.get('host', None)
+            if not host:
+                continue
+
+            nets = s.get('nets', [])
+            nl = []
+            for n in nets:
+                subnet = n[0]
+                width = n[1]
+                net = models.SshuttleNet.alloc().init()
+                net.setSubnet_(subnet)
+                net.setWidth_(width)
+                nl.append(net)
+
+            autoNets = s.get('autoNets', models.NET_AUTO)
+            autoHosts = s.get('autoHosts', True)
+            useDns = s.get('useDns', autoNets == models.NET_ALL)
+            latencyControl = s.get('latencyControl', models.LAT_INTERACTIVE)
+            srv = models.SshuttleServer.alloc().init()
+            srv.setHost_(host)
+            srv.setAutoNets_(autoNets)
+            srv.setAutoHosts_(autoHosts)
+            srv.setNets_(nl)
+            srv.setUseDns_(useDns)
+            srv.setLatencyControl_(latencyControl)
+            sl.append(srv)
+        self.serversController.addObjects_(sl)
+        self.serversController.setSelectionIndex_(0)
+
+    def save_servers(self):
+        l = []
+        for s in self.servers:
+            host = s.host()
+            if not host:
+                continue
+            nets = []
+            for n in s.nets():
+                subnet = n.subnet()
+                if not subnet:
+                    continue
+                nets.append((subnet, n.width()))
+            d = dict(host=s.host(),
+                     nets=nets,
+                     autoNets=s.autoNets(),
+                     autoHosts=s.autoHosts(),
+                     useDns=s.useDns(),
+                     latencyControl=s.latencyControl())
+            l.append(d)
+        my.Defaults().setObject_forKey_(l, 'servers')
+        self.fill_menu()
+
+    def awakeFromNib(self):
+        self.routingField.removeAllItems()
+        tf = self.routingField.addItemWithTitle_
+        tf('Send all traffic through this server')
+        tf('Determine automatically')
+        tf('Custom...')
+
+        self.latencyControlField.removeAllItems()
+        tf = self.latencyControlField.addItemWithTitle_
+        tf('Fast transfer')
+        tf('Low latency')
+
+        # Hmm, even when I mark this as !enabled in the .nib, it still comes
+        # through as enabled.  So let's just disable it here (since we don't
+        # support this feature yet).
+        self.startAtLoginField.setEnabled_(False)
+        self.startAtLoginField.setState_(False)
+        self.autoReconnectField.setEnabled_(False)
+        self.autoReconnectField.setState_(False)
+
+        self.load_servers()
+
+        # Initialize our menu item
+        self.menu = NSMenu.alloc().initWithTitle_('Sshuttle')
+        bar = NSStatusBar.systemStatusBar()
+        statusitem = bar.statusItemWithLength_(NSVariableStatusItemLength)
+        self.statusitem = statusitem
+        self.img_idle = NSImage.imageNamed_('ChickenIdleTemplate')
+        self.img_running = NSImage.imageNamed_('ChickenRunningTemplate')
+        self.img_err = NSImage.imageNamed_('ChickenErrorTemplate')
+        statusitem.setImage_(self.img_idle)
+        statusitem.setMenu_(self.menu)
+        self.fill_menu()
+
+        models.configchange_callback = my.DelayedCallback(self.save_servers)
+
+        def sc(server):
+            if server.wantConnect():
+                self._connect(server)
+            else:
+                self._disconnect(server)
+        models.setconnect_callback = sc
+
+
+# Note: NSApplicationMain calls sys.exit(), so this never returns.
+NSApplicationMain(sys.argv)

src/ui-macos/models.py

@@ -0,0 +1,189 @@
+from AppKit import (objc, NSObject)
+import my
+
+
+configchange_callback = setconnect_callback = None
+objc_validator = objc.signature('@@:N^@o^@')
+
+
+def config_changed():
+    if configchange_callback:
+        configchange_callback()
+
+
+def _validate_ip(v):
+    parts = v.split('.')[:4]
+    if len(parts) < 4:
+        parts += ['0'] * (4 - len(parts))
+    for i in range(4):
+        n = my.atoi(parts[i])
+        if n < 0:
+            n = 0
+        elif n > 255:
+            n = 255
+        parts[i] = str(n)
+    return '.'.join(parts)
+
+
+def _validate_width(v):
+    n = my.atoi(v)
+    if n < 0:
+        n = 0
+    elif n > 32:
+        n = 32
+    return n
+
+
+class SshuttleNet(NSObject):
+
+    def subnet(self):
+        return getattr(self, '_k_subnet', None)
+
+    def setSubnet_(self, v):
+        self._k_subnet = v
+        config_changed()
+
+    @objc_validator
+    def validateSubnet_error_(self, value, error):
+        # print 'validateSubnet!'
+        return True, _validate_ip(value), error
+
+    def width(self):
+        return getattr(self, '_k_width', 24)
+
+    def setWidth_(self, v):
+        self._k_width = v
+        config_changed()
+
+    @objc_validator
+    def validateWidth_error_(self, value, error):
+        # print 'validateWidth!'
+        return True, _validate_width(value), error
+
+NET_ALL = 0
+NET_AUTO = 1
+NET_MANUAL = 2
+
+LAT_BANDWIDTH = 0
+LAT_INTERACTIVE = 1
+
+
+class SshuttleServer(NSObject):
+
+    def init(self):
+        self = super(SshuttleServer, self).init()
+        config_changed()
+        return self
+
+    def wantConnect(self):
+        return getattr(self, '_k_wantconnect', False)
+
+    def setWantConnect_(self, v):
+        self._k_wantconnect = v
+        self.setError_(None)
+        config_changed()
+        if setconnect_callback:
+            setconnect_callback(self)
+
+    def connected(self):
+        return getattr(self, '_k_connected', False)
+
+    def setConnected_(self, v):
+        print 'setConnected of %r to %r' % (self, v)
+        self._k_connected = v
+        if v:
+            self.setError_(None)  # connected ok, so no error
+        config_changed()
+
+    def error(self):
+        return getattr(self, '_k_error', None)
+
+    def setError_(self, v):
+        self._k_error = v
+        config_changed()
+
+    def isValid(self):
+        if not self.host():
+            return False
+        if self.autoNets() == NET_MANUAL and not len(list(self.nets())):
+            return False
+        return True
+
+    def title(self):
+        host = self.host()
+        if not host:
+            return host
+        an = self.autoNets()
+        suffix = ""
+        if an == NET_ALL:
+            suffix = " (all traffic)"
+        elif an == NET_MANUAL:
+            n = self.nets()
+            suffix = ' (%d subnet%s)' % (len(n), len(n) != 1 and 's' or '')
+        return self.host() + suffix
+
+    def setTitle_(self, v):
+        # title is always auto-generated
+        config_changed()
+
+    def host(self):
+        return getattr(self, '_k_host', None)
+
+    def setHost_(self, v):
+        self._k_host = v
+        self.setTitle_(None)
+        config_changed()
+
+    @objc_validator
+    def validateHost_error_(self, value, error):
+        # print 'validatehost! %r %r %r' % (self, value, error)
+        while value.startswith('-'):
+            value = value[1:]
+        return True, value, error
+
+    def nets(self):
+        return getattr(self, '_k_nets', [])
+
+    def setNets_(self, v):
+        self._k_nets = v
+        self.setTitle_(None)
+        config_changed()
+
+    def netsHidden(self):
+        # print 'checking netsHidden'
+        return self.autoNets() != NET_MANUAL
+
+    def setNetsHidden_(self, v):
+        config_changed()
+        # print 'setting netsHidden to %r' % v
+
+    def autoNets(self):
+        return getattr(self, '_k_autoNets', NET_AUTO)
+
+    def setAutoNets_(self, v):
+        self._k_autoNets = v
+        self.setNetsHidden_(-1)
+        self.setUseDns_(v == NET_ALL)
+        self.setTitle_(None)
+        config_changed()
+
+    def autoHosts(self):
+        return getattr(self, '_k_autoHosts', True)
+
+    def setAutoHosts_(self, v):
+        self._k_autoHosts = v
+        config_changed()
+
+    def useDns(self):
+        return getattr(self, '_k_useDns', False)
+
+    def setUseDns_(self, v):
+        self._k_useDns = v
+        config_changed()
+
+    def latencyControl(self):
+        return getattr(self, '_k_latencyControl', LAT_INTERACTIVE)
+
+    def setLatencyControl_(self, v):
+        self._k_latencyControl = v
+        config_changed()

src/ui-macos/my.py

@@ -0,0 +1,70 @@
+import os
+from AppKit import (
+  NSBundle,
+  NSData,
+  NSDictionary,
+  NSImage,
+  NSUserDefaults,
+)
+import PyObjCTools.AppHelper
+
+
+def bundle_path(name, typ):
+    if typ:
+        return NSBundle.mainBundle().pathForResource_ofType_(name, typ)
+    else:
+        return os.path.join(NSBundle.mainBundle().resourcePath(), name)
+
+
+# Load an NSData using a python string
+def Data(s):
+    return NSData.alloc().initWithBytes_length_(s, len(s))
+
+
+# Load a property list from a file in the application bundle.
+def PList(name):
+    path = bundle_path(name, 'plist')
+    return NSDictionary.dictionaryWithContentsOfFile_(path)
+
+
+# Load an NSImage from a file in the application bundle.
+def Image(name, ext):
+    bytes = open(bundle_path(name, ext)).read()
+    img = NSImage.alloc().initWithData_(Data(bytes))
+    return img
+
+
+# Return the NSUserDefaults shared object.
+def Defaults():
+    return NSUserDefaults.standardUserDefaults()
+
+
+# Usage:
+#   f = DelayedCallback(func, args...)
+# later:
+#   f()
+#
+# When you call f(), it will schedule a call to func() next time the
+# ObjC event loop iterates.  Multiple calls to f() in a single iteration
+# will only result in one call to func().
+#
+def DelayedCallback(func, *args, **kwargs):
+    flag = [0]
+
+    def _go():
+        if flag[0]:
+            print 'running %r (flag=%r)' % (func, flag)
+            flag[0] = 0
+            func(*args, **kwargs)
+
+    def call():
+        flag[0] += 1
+        PyObjCTools.AppHelper.callAfter(_go)
+    return call
+
+
+def atoi(s):
+    try:
+        return int(s)
+    except ValueError:
+        return 0

src/ui-macos/run.do

@@ -0,0 +1,4 @@
+redo-ifchange debug.app
+exec >&2
+./debug.app/Contents/MacOS/Sshuttle
+

src/ui-macos/sources.list.do

@@ -0,0 +1,14 @@
+redo-always
+exec >$3
+cat <<-EOF
+	app.icns
+	MainMenu.nib English.lproj/MainMenu.nib
+	UserDefaults.plist
+	ChickenIdleTemplate.pdf
+	ChickenRunningTemplate.pdf
+	ChickenErrorTemplate.pdf
+EOF
+for d in *.py sshuttle/*.py sshuttle/sshuttle sshuttle/compat/*.py; do
+	echo $d
+done
+redo-stamp <$3

src/ui-macos/sshuttle

@@ -0,0 +1 @@
+..

sshuttle

@@ -1 +0,0 @@
-main.py