Seed hosts without auto hosts

A possible implementation for the change requested in #94, so that seed
hosts can be used without auto hosts. In this scenario only the
specified hosts (or ips) will be looked up (or rev looked up).

sshuttle/assembler.py

@@ -34,4 +34,4 @@ sshuttle.helpers.verbose = verbosity
 
 import sshuttle.cmdline_options as options
 from sshuttle.server import main
-main(options.latency_control)
+main(options.latency_control, options.auto_hosts)

sshuttle/client.py

@@ -400,7 +400,7 @@ def ondns(listener, method, mux, handlers):
 
 def _main(tcp_listener, udp_listener, fw, ssh_cmd, remotename,
           python, latency_control,
-          dns_listener, seed_hosts, auto_nets, daemon):
+          dns_listener, seed_hosts, auto_hosts, auto_nets, daemon):
 
     debug1('Starting client with Python version %s\n'
            % platform.python_version())
@@ -418,7 +418,8 @@ def _main(tcp_listener, udp_listener, fw, ssh_cmd, remotename,
         (serverproc, serversock) = ssh.connect(
             ssh_cmd, remotename, python,
             stderr=ssyslog._p and ssyslog._p.stdin,
-            options=dict(latency_control=latency_control))
+            options=dict(latency_control=latency_control,
+                auto_hosts=auto_hosts))
     except socket.error as e:
         if e.args[0] == errno.EPIPE:
             raise Fatal("failed to establish ssh session (1)")
@@ -514,7 +515,7 @@ def _main(tcp_listener, udp_listener, fw, ssh_cmd, remotename,
 
 def main(listenip_v6, listenip_v4,
          ssh_cmd, remotename, python, latency_control, dns, nslist,
-         method_name, seed_hosts, auto_nets,
+         method_name, seed_hosts, auto_hosts, auto_nets,
          subnets_include, subnets_exclude, daemon, pidfile):
 
     if daemon:
@@ -713,7 +714,7 @@ def main(listenip_v6, listenip_v4,
     try:
         return _main(tcp_listener, udp_listener, fw, ssh_cmd, remotename,
                      python, latency_control, dns_listener,
-                     seed_hosts, auto_nets, daemon)
+                     seed_hosts, auto_hosts, auto_nets, daemon)
     finally:
         try:
             if daemon:

sshuttle/cmdline.py

@@ -35,8 +35,6 @@ def main():
             if remotename == '' or remotename == '-':
                 remotename = None
             nslist = [family_ip_tuple(ns) for ns in opt.ns_hosts]
-            if opt.seed_hosts and not opt.auto_hosts:
-                parser.error('--seed-hosts only works if you also use -H')
             if opt.seed_hosts:
                 sh = re.split(r'[\s,]+', (opt.seed_hosts or "").strip())
             elif opt.auto_hosts:
@@ -69,6 +67,7 @@ def main():
                                       nslist,
                                       opt.method,
                                       sh,
+                                      opt.auto_hosts,
                                       opt.auto_nets,
                                       includes,
                                       excludes,

sshuttle/hostwatch.py

@@ -255,7 +255,7 @@ def _stdin_still_ok(timeout):
     return True
 
 
-def hw_main(seed_hosts):
+def hw_main(seed_hosts, auto_hosts):
     if helpers.verbose >= 2:
         helpers.logprefix = 'HH: '
     else:
@@ -264,16 +264,17 @@ def hw_main(seed_hosts):
     debug1('Starting hostwatch with Python version %s\n'
            % platform.python_version())
 
-    read_host_cache()
+    for h in seed_hosts:
+        check_host(h)
 
+    if auto_hosts:
+        read_host_cache()
         _enqueue(_check_etc_hosts)
         _enqueue(_check_netstat)
         check_host('localhost')
         check_host(socket.gethostname())
         check_workgroup('workgroup')
         check_workgroup('-')
-    for h in seed_hosts:
-        check_host(h)
 
     while 1:
         now = time.time()

sshuttle/server.py

@@ -98,7 +98,7 @@ def _exc_dump():
     return ''.join(traceback.format_exception(*exc_info))
 
 
-def start_hostwatch(seed_hosts):
+def start_hostwatch(seed_hosts, auto_hosts):
     s1, s2 = socket.socketpair()
     pid = os.fork()
     if not pid:
@@ -110,7 +110,7 @@ def start_hostwatch(seed_hosts):
                 os.dup2(s1.fileno(), 1)
                 os.dup2(s1.fileno(), 0)
                 s1.close()
-                rv = hostwatch.hw_main(seed_hosts) or 0
+                rv = hostwatch.hw_main(seed_hosts, auto_hosts) or 0
             except Exception:
                 log('%s\n' % _exc_dump())
                 rv = 98
@@ -227,7 +227,7 @@ class UdpProxy(Handler):
         self.mux.send(self.chan, ssnet.CMD_UDP_DATA, hdr + data)
 
 
-def main(latency_control):
+def main(latency_control, auto_hosts):
     debug1('Starting server with Python version %s\n'
            % platform.python_version())
 
@@ -277,7 +277,8 @@ def main(latency_control):
 
     def got_host_req(data):
         if not hw.pid:
-            (hw.pid, hw.sock) = start_hostwatch(data.strip().split())
+            (hw.pid, hw.sock) = start_hostwatch(
+                    data.strip().split(), auto_hosts)
             handlers.append(Handler(socks=[hw.sock],
                                     callback=hostwatch_ready))
     mux.got_host_req = got_host_req