1 files changed, 176 insertions, 0 deletions
diff --git a/Sshuttle VPN.app/Contents/Resources/sshuttle/server.py b/Sshuttle VPN.app/Contents/Resources/sshuttle/server.py
new file mode 100644
index 0000000..24dd462
--- /dev/null
+++ b/Sshuttle VPN.app/Contents/Resources/sshuttle/server.py
@@ -0,0 +1,176 @@
+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()