Don't bother with a backtrace when we produce certain fatal errors.

We'll introduce a new "Fatal" exception for this purpose, and throw it when
we just want to print a user message and abort immediately.

client.py

@@ -20,27 +20,31 @@ def iptables_setup(port, subnets):
             ['--iptables', str(port)] + subnets_str)
     rv = subprocess.call(argv)
     if rv != 0:
-        raise Exception('%r returned %d' % (argv, rv))
+        raise Fatal('%r returned %d' % (argv, rv))
 
 
 def _main(listener, listenport, use_server, remotename, subnets):
     handlers = []
     if use_server:
-        helpers.logprefix = 'c : '
+        if helpers.verbose >= 1:
+            helpers.logprefix = 'c : '
+        else:
+            helpers.logprefix = 'client: '
         (serverproc, serversock) = ssh.connect(remotename)
         mux = Mux(serversock, serversock)
         handlers.append(mux)
 
         expected = 'SSHUTTLE0001'
         initstring = serversock.recv(len(expected))
-        if initstring != expected:
-            raise Exception('expected server init string %r; got %r'
-                            % (expected, initstring))
-
+        
         rv = serverproc.poll()
         if rv:
-            raise Exception('server died with error code %d' % rv)
+            raise Fatal('server died with error code %d' % rv)
             
+        if initstring != expected:
+            raise Fatal('expected server init string %r; got %r'
+                            % (expected, initstring))
+
     # we definitely want to do this *after* starting ssh, or we might end
     # up intercepting the ssh connection!
     iptables_setup(listenport, subnets)
@@ -67,7 +71,7 @@ def _main(listener, listenport, use_server, remotename, subnets):
         if use_server:
             rv = serverproc.poll()
             if rv:
-                raise Exception('server died with error code %d' % rv)
+                raise Fatal('server died with error code %d' % rv)
         
         r = set()
         w = set()

helpers.py

@@ -15,3 +15,7 @@ def debug1(s):
 def debug2(s):
     if verbose >= 2:
         log(s)
+
+
+class Fatal(Exception):
+    pass

main.py

 #!/usr/bin/env python
 import sys, os, re
 import helpers, options, client, server, iptables
+from helpers import *
 
 
 # list of:
@@ -10,7 +11,7 @@ def parse_subnets(subnets_str):
     for s in subnets_str:
         m = re.match(r'(\d+)(?:\.(\d+)\.(\d+)\.(\d+))?(?:/(\d+))?$', s)
         if not m:
-            raise Exception('%r is not a valid IP subnet format' % s)
+            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:
@@ -18,9 +19,9 @@ def parse_subnets(subnets_str):
         else:
             width = int(width)
         if a > 255 or b > 255 or c > 255 or d > 255:
-            raise Exception('%d.%d.%d.%d has numbers > 255' % (a,b,c,d))
+            raise Fatal('%d.%d.%d.%d has numbers > 255' % (a,b,c,d))
         if width > 32:
-            raise Exception('*/%d is greater than the maximum of 32' % width)
+            raise Fatal('*/%d is greater than the maximum of 32' % width)
         subnets.append(('%d.%d.%d.%d' % (a,b,c,d), width))
     return subnets
 
@@ -30,14 +31,14 @@ def parse_ipport(s):
     s = str(s)
     m = re.match(r'(?:(\d+)\.(\d+)\.(\d+)\.(\d+))?(?::)?(?:(\d+))?$', s)
     if not m:
-        raise Exception('%r is not a valid IP:port format' % s)
+        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 Exception('%d.%d.%d.%d has numbers > 255' % (a,b,c,d))
+        raise Fatal('%d.%d.%d.%d has numbers > 255' % (a,b,c,d))
     if port > 65535:
-        raise Exception('*:%d is greater than the maximum of 65535' % port)
+        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)
@@ -60,20 +61,27 @@ o = options.Options('sshuttle', optspec)
 
 helpers.verbose = opt.verbose
 
-if opt.server:
-    sys.exit(server.main())
-elif opt.iptables:
-    if len(extra) < 1:
-        o.fatal('at least one argument expected')
-    sys.exit(iptables.main(int(extra[0]),
-                           parse_subnets(extra[1:])))
-else:
-    if len(extra) < 1:
-        o.fatal('at least one subnet expected')
-    remotename = opt.remote
-    if remotename == '' or remotename == '-':
-        remotename = None
-    sys.exit(client.main(parse_ipport(opt.listen or '0.0.0.0:0'),
-                         not opt.noserver,
-                         remotename,
-                         parse_subnets(extra)))
+try:
+    if opt.server:
+        sys.exit(server.main())
+    elif opt.iptables:
+        if len(extra) < 1:
+            o.fatal('at least one argument expected')
+        sys.exit(iptables.main(int(extra[0]),
+                               parse_subnets(extra[1:])))
+    else:
+        if len(extra) < 1:
+            o.fatal('at least one subnet expected')
+        remotename = opt.remote
+        if remotename == '' or remotename == '-':
+            remotename = None
+        sys.exit(client.main(parse_ipport(opt.listen or '0.0.0.0:0'),
+                             not opt.noserver,
+                             remotename,
+                             parse_subnets(extra)))
+except Fatal, e:
+    log('fatal: %s\n' % e)
+    sys.exit(99)
+except KeyboardInterrupt:
+    log('\nKeyboard interrupt: exiting.\n')
+    sys.exit(1)

server.py

@@ -8,8 +8,11 @@ def main():
     # synchronization header
     sys.stdout.write('SSHUTTLE0001')
     sys.stdout.flush()
-    
-    helpers.logprefix = ' s: '
+
+    if helpers.verbose >= 1:
+        helpers.logprefix = ' s: '
+    else:
+        helpers.logprefix = 'server: '
     handlers = []
     mux = Mux(socket.fromfd(sys.stdin.fileno(),
                             socket.AF_INET, socket.SOCK_STREAM),

ssh.py

@@ -19,10 +19,9 @@ def connect(rhost):
         # stuff here.
         escapedir = re.sub(r'([^\w/])', r'\\\\\\\1', nicedir)
         cmd = r"""
-                   sh -c PATH=%s:'$PATH exec sshuttle --server'
-               """ % (escapedir,)
+                   sh -c PATH=%s:'$PATH exec sshuttle --server%s'
+               """ % (escapedir, ' -v' * (helpers.verbose or 0))
         argv = ['ssh', rhost, '--', cmd.strip()]
-        print repr(argv)
     (s1,s2) = socket.socketpair()
     def setup():
         # runs in the child process