Merge branch 'pull/31'

* Merging pull request apenwarr#31.

Author: Hasimir

Documentation/sshuttle.md

@@ -36,7 +36,12 @@ entire subnet to the VPN.
     single IP address), 1.2.3.4/32 (equivalent to 1.2.3.4),
     1.2.3.0/24 (a 24-bit subnet, ie. with a 255.255.255.0
     netmask), and 0/0 ('just route everything through the
-    VPN').
+    VPN'). In addition, it is also possible to filter
+    additionally on the tcp port to include/exclude.
+    This is done by adding :port at the end of your netmask.
+    Note that `:port` is also valid. In this case, the netmask
+    will be defaulted to 0/0. Valid examples are `:80`,
+    `0:80`, `1.2.3.4:80` and `1.2.3.4/24:80`.
 
 -l, --listen=*[ip:]port*
 :   use this ip address and port number as the transparent

client.py

@@ -160,10 +160,10 @@ def check(self):
 
     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))
+        for (ip,width,port) in self.subnets_include+self.auto_nets:
+            self.pfile.write('%d,%d,0,%s\n' % (width, port, ip))
+        for (ip,width,port) in self.subnets_exclude:
+            self.pfile.write('%d,%d,1,%s\n' % (width, port, ip))
         self.pfile.write('GO\n')
         self.pfile.flush()
         line = self.pfile.readline()

firewall.py

@@ -1,3 +1,5 @@
+# vim: set tabstop=4 expandtab :
+
 import re, errno, socket, select, signal, struct
 import compat.ssubprocess as ssubprocess
 import helpers, ssyslog
@@ -106,17 +108,36 @@ def do_iptables(port, dnsport, route_username, excludedports, subnets):
         # 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):
+        for swidth,sport,sexclude,snet in sorted(subnets, reverse=True):
             if sexclude:
-                ipt('-A', chain, '-j', 'RETURN',
-                    '--dest', '%s/%s' % (snet,swidth),
-                    '-p', 'tcp')
+                if sport > 0:
+                    ipt('-A', chain, '-j', 'RETURN',
+                        '--dest', '%s/%s' % (snet,swidth),
+                        '-m', 'tcp',
+                        '--dport', '%d' % sport,
+                        '-p', 'tcp')
+                else:
+                    ipt('-A', chain, '-j', 'RETURN',
+                        '--dest', '%s/%s' % (snet,swidth),
+                        '-p', 'tcp')
             else:
-                ipt_ttl('-A', chain, '-j', 'REDIRECT',
+                if sport > 0:
+                    ipt_ttl('-A', chain, '-j', 'REDIRECT',
                         '--dest', '%s/%s' % (snet,swidth),
+                        '-m', 'tcp',
+                        '--dport', '%d' % sport,
                         '-p', 'tcp',
+<<<<<<< HEAD
                         '--to-ports', str(port),
                          *eportsargv)
+=======
+                        '--to-ports', str(port))
+                else:
+                    ipt_ttl('-A', chain, '-j', 'REDIRECT',
+                        '--dest', '%s/%s' % (snet,swidth),
+                        '-p', 'tcp',
+                        '--to-ports', str(port))
+>>>>>>> pull/31
 
     if dnsport:
         for ip in nslist:
@@ -327,16 +348,29 @@ def do_ipfw(port, dnsport, route_username, excludedports, subnets):
 
     if subnets:
         # create new subnet entries
-        for swidth,sexclude,snet in sorted(subnets, reverse=True):
+        for swidth,dport,sexclude,snet in sorted(subnets, reverse=True):
             if sexclude:
-                ipfw('add', sport, 'skipto', xsport,
-                     'tcp',
-                     'from', 'any', 'to', '%s/%s' % (snet,swidth))
+                if dport > 0:
+                    ipfw('add', sport, 'skipto', xsport,
+                        'tcp',
+                        'from', 'any', 'to', '%s/%s' % (snet,swidth),
+                         '%d' % dport)
+                else:
+                    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')
+                if dport > 0:
+                    ipfw('add', sport, 'fwd', '127.0.0.1,%d' % port,
+                        'tcp',
+                        'from', 'any', 'to', '%s/%s' % (snet,swidth),
+                         '%d' % dport,
+                        'not', 'ipttl', '42', 'keep-state', 'setup')
+                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
@@ -529,10 +563,10 @@ def main(port, dnsport, syslog, route_username, excludedports):
         elif line == 'GO\n':
             break
         try:
-            (width,exclude,ip) = line.strip().split(',', 2)
+            (width,dport,exclude,ip) = line.strip().split(',', 3)
         except:
             raise Fatal('firewall: expected route or GO but got %r' % line)
-        subnets.append((int(width), bool(int(exclude)), ip))
+        subnets.append((int(width), int(dport), bool(int(exclude)), ip))
 
     try:
         if line:

main.py

@@ -1,3 +1,4 @@
+# vim: set tabstop=4 expandtab :
 import sys, os, re
 import helpers, options, client, server, firewall, hostwatch
 import compat.ssubprocess as ssubprocess
@@ -9,11 +10,16 @@
 def parse_subnets(subnets_str):
     subnets = []
     for s in subnets_str:
-        m = re.match(r'(\d+)(?:\.(\d+)\.(\d+)\.(\d+))?(?:/(\d+))?$', s)
+        m = re.match(r'(\d+)?(?:\.(\d+)\.(\d+)\.(\d+))?(?:/(\d+))?(:\d+)?$', 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,width,port) = m.groups()
         (a,b,c,d) = (int(a or 0), int(b or 0), int(c or 0), int(d or 0))
+        if port == None:
+            port = 0
+        else:
+            port = int(re.sub('^:','',port))
+
         if width == None:
             width = 32
         else:
@@ -22,7 +28,10 @@ def parse_subnets(subnets_str):
             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))
+        if port > 65535:
+            raise Fatal('*:%d is greater than the maximum of 65535' % port)
+        subnets.append(('%d.%d.%d.%d' % (a,b,c,d), width, port))
+
     return subnets
 
 
@@ -57,7 +66,7 @@ def parse_ipport(s):
 dns-hosts= capture DNS requests to these servers and forward (comma-separated)
 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= exclude this subnet and/or port (can be used more than once)
 exclude-from=  exclude the subnets in a file (whitespace separated)
 v,verbose  increase debug message verbosity
 e,ssh-cmd= the command to use to connect to the remote [ssh]