Ensure locale is set to C for external commands

Otherwise the output can vary and confuse our attempts to parse it.

Fixes: 93

sshuttle/linux.py

+import os
 import socket
 import subprocess as ssubprocess
 from sshuttle.helpers import log, debug1, Fatal, family_to_string
@@ -18,7 +19,11 @@ def ipt_chain_exists(family, table, name):
     else:
         raise Exception('Unsupported family "%s"' % family_to_string(family))
     argv = [cmd, '-t', table, '-nL']
-    p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE)
+    env = {
+        'PATH': os.environ['PATH'],
+        'LC_ALL': "C",
+    }
+    p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, env=env)
     for line in p.stdout:
         if line.startswith(b'Chain %s ' % name.encode("ASCII")):
             return True
@@ -35,7 +40,11 @@ def ipt(family, table, *args):
     else:
         raise Exception('Unsupported family "%s"' % family_to_string(family))
     debug1('>> %s\n' % ' '.join(argv))
-    rv = ssubprocess.call(argv)
+    env = {
+        'PATH': os.environ['PATH'],
+        'LC_ALL': "C",
+    }
+    rv = ssubprocess.call(argv, env=env)
     if rv:
         raise Fatal('%r returned %d' % (argv, rv))
 

sshuttle/methods/pf.py

@@ -326,9 +326,14 @@ def pfctl(args, stdin=None):
     argv = ['pfctl'] + list(args.split(" "))
     debug1('>> %s\n' % ' '.join(argv))
 
+    env = {
+        'PATH': os.environ['PATH'],
+        'LC_ALL': "C",
+    }
     p = ssubprocess.Popen(argv, stdin=ssubprocess.PIPE,
                           stdout=ssubprocess.PIPE,
-                          stderr=ssubprocess.PIPE)
+                          stderr=ssubprocess.PIPE,
+                          env=env)
     o = p.communicate(stdin)
     if p.returncode:
         raise Fatal('%r returned %d' % (argv, p.returncode))

sshuttle/server.py

@@ -63,7 +63,11 @@ def _shl(n, bits):
 def _list_routes():
     # FIXME: IPv4 only
     argv = ['netstat', '-rn']
-    p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE)
+    env = {
+        'PATH': os.environ['PATH'],
+        'LC_ALL': "C",
+    }
+    p = ssubprocess.Popen(argv, stdout=ssubprocess.PIPE, env=env)
     routes = []
     for line in p.stdout:
         cols = re.split(r'\s+', line.decode("ASCII"))