Fixes some style issues and minor bugs

.prospector.yml

@@ -10,6 +10,11 @@ pylint:
     - bare-except
     - protected-access
     - no-else-return
+    - unused-argument
+    - method-hidden
+    - arguments-differ
+    - wrong-import-position
+    - raising-bad-type
 
 pep8:
   options:

sshuttle/client.py

@@ -112,8 +112,8 @@ def daemon_cleanup():
 
 class MultiListener:
 
-    def __init__(self, type=socket.SOCK_STREAM, proto=0):
-        self.type = type
+    def __init__(self, kind=socket.SOCK_STREAM, proto=0):
+        self.type = kind
         self.proto = proto
         self.v6 = None
         self.v4 = None
@@ -746,22 +746,22 @@ def main(listenip_v6, listenip_v4,
     # Last minute sanity checks.
     # These should never fail.
     # If these do fail, something is broken above.
-    if len(subnets_v6) > 0:
+    if subnets_v6:
         assert required.ipv6
         if redirectport_v6 == 0:
             raise Fatal("IPv6 subnets defined but not listening")
 
-    if len(nslist_v6) > 0:
+    if nslist_v6:
         assert required.dns
         assert required.ipv6
         if dnsport_v6 == 0:
             raise Fatal("IPv6 ns servers defined but not listening")
 
-    if len(subnets_v4) > 0:
+    if subnets_v4:
         if redirectport_v4 == 0:
             raise Fatal("IPv4 subnets defined but not listening")
 
-    if len(nslist_v4) > 0:
+    if nslist_v4:
         if dnsport_v4 == 0:
             raise Fatal("IPv4 ns servers defined but not listening")
 

sshuttle/cmdline.py

@@ -45,8 +45,8 @@ def main():
             if opt.listen:
                 ipport_v6 = None
                 ipport_v4 = None
-                list = opt.listen.split(",")
-                for ip in list:
+                lst = opt.listen.split(",")
+                for ip in lst:
                     family, ip, port = parse_ipport(ip)
                     if family == socket.AF_INET6:
                         ipport_v6 = (ip, port)

sshuttle/firewall.py

@@ -2,6 +2,7 @@ import errno
 import socket
 import signal
 import sshuttle.ssyslog as ssyslog
+import sshuttle.sdnotify as sdnotify
 import sys
 import os
 import platform
@@ -164,7 +165,7 @@ def main(method_name, syslog):
     _, _, ports = line.partition(" ")
     ports = ports.split(",")
     if len(ports) != 4:
-        raise Fatal('firewall: expected 4 ports but got %n' % len(ports))
+        raise Fatal('firewall: expected 4 ports but got %d' % len(ports))
     port_v6 = int(ports[0])
     port_v4 = int(ports[1])
     dnsport_v6 = int(ports[2])
@@ -203,14 +204,14 @@ def main(method_name, syslog):
     try:
         debug1('firewall manager: setting up.\n')
 
-        if len(subnets_v6) > 0 or len(nslist_v6) > 0:
+        if subnets_v6 or nslist_v6:
             debug2('firewall manager: setting up IPv6.\n')
             method.setup_firewall(
                 port_v6, dnsport_v6, nslist_v6,
                 socket.AF_INET6, subnets_v6, udp,
                 user)
 
-        if len(subnets_v4) > 0 or len(nslist_v4) > 0:
+        if subnets_v4 or nslist_v4:
             debug2('firewall manager: setting up IPv4.\n')
             method.setup_firewall(
                 port_v4, dnsport_v4, nslist_v4,
@@ -249,7 +250,7 @@ def main(method_name, syslog):
             pass
 
         try:
-            if len(subnets_v6) > 0 or len(nslist_v6) > 0:
+            if subnets_v6 or nslist_v6:
                 debug2('firewall manager: undoing IPv6 changes.\n')
                 method.restore_firewall(port_v6, socket.AF_INET6, udp, user)
         except:
@@ -262,7 +263,7 @@ def main(method_name, syslog):
                 pass
 
         try:
-            if len(subnets_v4) > 0 or len(nslist_v4) > 0:
+            if subnets_v4 or nslist_v4:
                 debug2('firewall manager: undoing IPv4 changes.\n')
                 method.restore_firewall(port_v4, socket.AF_INET, udp, user)
         except:

sshuttle/hostwatch.py

@@ -251,7 +251,7 @@ def _enqueue(op, *args):
 
 
 def _stdin_still_ok(timeout):
-    r, w, x = select.select([sys.stdin.fileno()], [], [], timeout)
+    r, _, _ = select.select([sys.stdin.fileno()], [], [], timeout)
     if r:
         b = os.read(sys.stdin.fileno(), 4096)
         if not b:

sshuttle/methods/__init__.py

@@ -74,7 +74,8 @@ class BaseMethod(object):
                     "Feature %s not supported with method %s.\n" %
                     (key, self.name))
 
-    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp, user):
+    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
+                       user):
         raise NotImplementedError()
 
     def restore_firewall(self, port, family, udp, user):

sshuttle/methods/ipfw.py

 import os
-import sys
-import struct
 import subprocess as ssubprocess
 from sshuttle.methods import BaseMethod
 from sshuttle.helpers import log, debug1, debug3, \
@@ -31,9 +29,9 @@ IPV6_RECVDSTADDR = 74
 if recvmsg == "python":
     def recv_udp(listener, bufsize):
         debug3('Accept UDP python using recvmsg.\n')
-        data, ancdata, msg_flags, srcip = listener.recvmsg(4096, socket.CMSG_SPACE(4))
+        data, ancdata, _, srcip = \
+                listener.recvmsg(4096, socket.CMSG_SPACE(4))
         dstip = None
-        family = None
         for cmsg_level, cmsg_type, cmsg_data in ancdata:
             if cmsg_level == socket.SOL_IP and cmsg_type == IP_RECVDSTADDR:
                 port = 53
@@ -44,13 +42,13 @@ if recvmsg == "python":
 elif recvmsg == "socket_ext":
     def recv_udp(listener, bufsize):
         debug3('Accept UDP using socket_ext recvmsg.\n')
-        srcip, data, adata, flags = listener.recvmsg((bufsize,), socket.CMSG_SPACE(4))
+        srcip, data, adata, _ = \
+                listener.recvmsg((bufsize,), socket.CMSG_SPACE(4))
         dstip = None
-        family = None
         for a in adata:
             if a.cmsg_level == socket.SOL_IP and a.cmsg_type == IP_RECVDSTADDR:
                 port = 53
-                ip = socket.inet_ntop(socket.AF_INET, cmsg_data[0:4])
+                ip = socket.inet_ntop(socket.AF_INET, a.cmsg_data[0:4])
                 dstip = (ip, port)
                 break
         return (srcip, dstip, data[0])
@@ -75,7 +73,7 @@ def ipfw_rule_exists(n):
             if not ('ipttl 42' in line or 'check-state' in line):
                 log('non-sshuttle ipfw rule: %r\n' % line.strip())
                 raise Fatal('non-sshuttle ipfw rule #%d already exists!' % n)
-                found = True
+            found = True
     rv = p.wait()
     if rv:
         raise Fatal('%r returned %d' % (argv, rv))
@@ -193,7 +191,8 @@ class Method(BaseMethod):
         #if udp_listener.v6 is not None:
         #    udp_listener.v6.setsockopt(SOL_IPV6, IPV6_RECVDSTADDR, 1)
 
-    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp, user):
+    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
+                       user):
         # IPv6 not supported
         if family not in [socket.AF_INET]:
             raise Exception(
@@ -224,7 +223,7 @@ class Method(BaseMethod):
 
         ipfw_noexit('table', '124', 'flush')
         dnscount = 0
-        for f, ip in [i for i in nslist if i[0] == family]:
+        for _, ip in [i for i in nslist if i[0] == family]:
             ipfw('table', '124', 'add', '%s' % (ip))
             dnscount += 1
         if dnscount > 0:
@@ -232,23 +231,14 @@ class Method(BaseMethod):
                  'udp',
                  'from', 'any', 'to', 'table(124)',
                  'not', 'ipttl', '42')
-        """if udp:
-            ipfw('add', '1', 'skipto', '2',
-                 'udp',
-                 'from', 'any', 'to', 'table(125)')
-            ipfw('add', '1', 'fwd', '127.0.0.1,%d' % port,
-                 'udp',
-                 'from', 'any', 'to', 'table(126)',
-                 'not', 'ipttl', '42')
-        """
-        ipfw('add', '1', 'allow', 
+        ipfw('add', '1', 'allow',
              'udp',
              'from', 'any', 'to', 'any',
              'ipttl', '42')
 
         if subnets:
             # create new subnet entries
-            for f, swidth, sexclude, snet \
+            for _, swidth, sexclude, snet \
                 in sorted(subnets, key=lambda s: s[1], reverse=True):
                 if sexclude:
                     ipfw('table', '125', 'add', '%s/%s' % (snet, swidth))
@@ -265,4 +255,3 @@ class Method(BaseMethod):
         ipfw_noexit('table', '124', 'flush')
         ipfw_noexit('table', '125', 'flush')
         ipfw_noexit('table', '126', 'flush')
-

sshuttle/methods/nat.py

@@ -12,7 +12,8 @@ class Method(BaseMethod):
     # the multiple copies shouldn't have overlapping subnets, or only the most-
     # recently-started one will win (because we use "-I OUTPUT 1" instead of
     # "-A OUTPUT").
-    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp, user):
+    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
+                       user):
         # only ipv4 supported with NAT
         if family != socket.AF_INET:
             raise Exception(
@@ -50,7 +51,7 @@ class Method(BaseMethod):
         _ipt('-I', 'PREROUTING', '1', *args)
 
         # create new subnet entries.
-        for f, swidth, sexclude, snet, fport, lport \
+        for _, swidth, sexclude, snet, fport, lport \
                 in sorted(subnets, key=subnet_weight, reverse=True):
             tcp_ports = ('-p', 'tcp')
             if fport:
@@ -65,7 +66,7 @@ class Method(BaseMethod):
                          '--dest', '%s/%s' % (snet, swidth),
                          *(tcp_ports + ('--to-ports', str(port))))
 
-        for f, ip in [i for i in nslist if i[0] == family]:
+        for _, ip in [i for i in nslist if i[0] == family]:
             _ipt_ttl('-A', chain, '-j', 'REDIRECT',
                      '--dest', '%s/32' % ip,
                      '-p', 'udp',
@@ -97,8 +98,8 @@ class Method(BaseMethod):
         # basic cleanup/setup of chains
         if ipt_chain_exists(family, table, chain):
             if user is not None:
-                nonfatal(_ipm, '-D', 'OUTPUT', '-m', 'owner', '--uid-owner', str(user),
-                         '-j', 'MARK', '--set-mark', str(port))
+                nonfatal(_ipm, '-D', 'OUTPUT', '-m', 'owner', '--uid-owner',
+                         str(user), '-j', 'MARK', '--set-mark', str(port))
                 args = '-m', 'mark', '--mark', str(port), '-j', chain
             else:
                 args = '-j', chain

sshuttle/methods/pf.py

@@ -115,21 +115,21 @@ class Generic(object):
         if ('\nanchor "%s"' % anchor).encode('ASCII') not in status:
             self._add_anchor_rule(self.PF_PASS, anchor.encode('ASCII'))
 
-    def _add_anchor_rule(self, type, name, pr=None):
+    def _add_anchor_rule(self, kind, name, pr=None):
         if pr is None:
             pr = self.pfioc_rule()
 
         memmove(addressof(pr) + self.ANCHOR_CALL_OFFSET, name,
-                min(self.MAXPATHLEN, len(name)))  # anchor_call = name
+                min(self.MAXPATHLEN, len(name))) # anchor_call = name
         memmove(addressof(pr) + self.RULE_ACTION_OFFSET,
-                struct.pack('I', type), 4)  # rule.action = type
+                struct.pack('I', kind), 4) # rule.action = kind
 
         memmove(addressof(pr) + self.ACTION_OFFSET, struct.pack(
-            'I', self.PF_CHANGE_GET_TICKET), 4)  # action = PF_CHANGE_GET_TICKET
+            'I', self.PF_CHANGE_GET_TICKET), 4) # action = PF_CHANGE_GET_TICKET
         ioctl(pf_get_dev(), pf.DIOCCHANGERULE, pr)
 
         memmove(addressof(pr) + self.ACTION_OFFSET, struct.pack(
-            'I', self.PF_CHANGE_ADD_TAIL), 4)  # action = PF_CHANGE_ADD_TAIL
+            'I', self.PF_CHANGE_ADD_TAIL), 4) # action = PF_CHANGE_ADD_TAIL
         ioctl(pf_get_dev(), pf.DIOCCHANGERULE, pr)
 
     @staticmethod
@@ -176,9 +176,6 @@ class FreeBsd(Generic):
         freebsd.pfioc_natlook = pfioc_natlook
         return freebsd
 
-    def __init__(self):
-        super(FreeBsd, self).__init__()
-
     def enable(self):
         returncode = ssubprocess.call(['kldload', 'pf'])
         super(FreeBsd, self).enable()
@@ -197,14 +194,14 @@ class FreeBsd(Generic):
             self._add_anchor_rule(self.PF_RDR, anchor.encode('ASCII'))
         super(FreeBsd, self).add_anchors(anchor, status=status)
 
-    def _add_anchor_rule(self, type, name):
-        pr = self.pfioc_rule()
+    def _add_anchor_rule(self, kind, name, pr=None):
+        pr = pr or self.pfioc_rule()
         ppa = self.pfioc_pooladdr()
 
         ioctl(pf_get_dev(), self.DIOCBEGINADDRS, ppa)
         # pool ticket
         memmove(addressof(pr) + self.POOL_TICKET_OFFSET, ppa[4:8], 4)
-        super(FreeBsd, self)._add_anchor_rule(type, name, pr=pr)
+        super(FreeBsd, self)._add_anchor_rule(kind, name, pr=pr)
 
     def add_rules(self, anchor, includes, port, dnsport, nslist, family):
         inet_version = self._inet_version(family)
@@ -224,7 +221,7 @@ class FreeBsd(Generic):
             for exclude, subnet in includes
         ]
 
-        if len(nslist) > 0:
+        if nslist:
             tables.append(
                 b'table <dns_servers> {%s}' %
                 b','.join([ns[1].encode("ASCII") for ns in nslist]))
@@ -294,7 +291,7 @@ class OpenBsd(Generic):
             for exclude, subnet in includes
         ]
 
-        if len(nslist) > 0:
+        if nslist:
             tables.append(
                 b'table <dns_servers> {%s}' %
                 b','.join([ns[1].encode("ASCII") for ns in nslist]))
@@ -440,11 +437,8 @@ class Method(BaseMethod):
 
         return sock.getsockname()
 
-    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp, user):
-        tables = []
-        translating_rules = []
-        filtering_rules = []
-
+    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
+                       user):
         if family not in [socket.AF_INET, socket.AF_INET6]:
             raise Exception(
                 'Address family "%s" unsupported by pf method_name'
@@ -452,12 +446,12 @@ class Method(BaseMethod):
         if udp:
             raise Exception("UDP not supported by pf method_name")
 
-        if len(subnets) > 0:
+        if subnets:
             includes = []
             # If a given subnet is both included and excluded, list the
             # exclusion first; the table will ignore the second, opposite
             # definition
-            for f, swidth, sexclude, snet, fport, lport \
+            for _, swidth, sexclude, snet, fport, lport \
                     in sorted(subnets, key=subnet_weight, reverse=True):
                 includes.append((sexclude, b"%s/%d%s" % (
                     snet.encode("ASCII"),

sshuttle/methods/tproxy.py

@@ -33,7 +33,7 @@ IPV6_RECVORIGDSTADDR = IPV6_ORIGDSTADDR
 if recvmsg == "python":
     def recv_udp(listener, bufsize):
         debug3('Accept UDP python using recvmsg.\n')
-        data, ancdata, msg_flags, srcip = listener.recvmsg(
+        data, ancdata, _, srcip = listener.recvmsg(
             4096, socket.CMSG_SPACE(24))
         dstip = None
         family = None
@@ -64,7 +64,7 @@ if recvmsg == "python":
 elif recvmsg == "socket_ext":
     def recv_udp(listener, bufsize):
         debug3('Accept UDP using socket_ext recvmsg.\n')
-        srcip, data, adata, flags = listener.recvmsg(
+        srcip, data, adata, _ = listener.recvmsg(
             (bufsize,), socket.CMSG_SPACE(24))
         dstip = None
         family = None
@@ -150,7 +150,8 @@ class Method(BaseMethod):
         if udp_listener.v6 is not None:
             udp_listener.v6.setsockopt(SOL_IPV6, IPV6_RECVORIGDSTADDR, 1)
 
-    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp, user):
+    def setup_firewall(self, port, dnsport, nslist, family, subnets, udp,
+                       user):
         if family not in [socket.AF_INET, socket.AF_INET6]:
             raise Exception(
                 'Address family "%s" unsupported by tproxy method'
@@ -193,7 +194,7 @@ class Method(BaseMethod):
             _ipt('-A', tproxy_chain, '-m', 'socket', '-j', divert_chain,
                  '-m', 'udp', '-p', 'udp')
 
-        for f, ip in [i for i in nslist if i[0] == family]:
+        for _, ip in [i for i in nslist if i[0] == family]:
             _ipt('-A', mark_chain, '-j', 'MARK', '--set-mark', '1',
                  '--dest', '%s/32' % ip,
                  '-m', 'udp', '-p', 'udp', '--dport', '53')
@@ -203,7 +204,7 @@ class Method(BaseMethod):
                  '-m', 'udp', '-p', 'udp', '--dport', '53',
                  '--on-port', str(dnsport))
 
-        for f, swidth, sexclude, snet, fport, lport \
+        for _, swidth, sexclude, snet, fport, lport \
                 in sorted(subnets, key=subnet_weight, reverse=True):
             tcp_ports = ('-p', 'tcp')
             tcp_ports = _ipt_proto_ports(tcp_ports, fport, lport)

sshuttle/options.py

@@ -13,9 +13,9 @@ def parse_subnetport_file(s):
 
     raw_config_lines = handle.readlines()
     subnets = []
-    for line_no, line in enumerate(raw_config_lines):
+    for _, line in enumerate(raw_config_lines):
         line = line.strip()
-        if len(line) == 0:
+        if not line:
             continue
         if line[0] == '#':
             continue
@@ -81,8 +81,8 @@ def parse_ipport(s):
     return (family,) + addr[:2]
 
 
-def parse_list(list):
-    return re.split(r'[\s,]+', list.strip()) if list else []
+def parse_list(lst):
+    return re.split(r'[\s,]+', lst.strip()) if lst else []
 
 
 class Concat(Action):
@@ -120,7 +120,8 @@ parser.add_argument(
     "-H", "--auto-hosts",
     action="store_true",
     help="""
-    continuously scan for remote hostnames and update local /etc/hosts as they are found
+    continuously scan for remote hostnames and update local /etc/hosts as
+    they are found
     """
 )
 parser.add_argument(
@@ -151,7 +152,8 @@ parser.add_argument(
     metavar="IP[:PORT]",
     type=parse_ipport,
     help="""
-    the DNS server to forward requests to; defaults to servers in /etc/resolv.conf on remote side if not given.
+    the DNS server to forward requests to; defaults to servers in
+    /etc/resolv.conf on remote side if not given.
     """
 )
 
@@ -227,7 +229,8 @@ parser.add_argument(
     metavar="HOSTNAME[,HOSTNAME]",
     default=[],
     help="""
-    comma-separated list of hostnames for initial scan (may be used with or without --auto-hosts)
+    comma-separated list of hostnames for initial scan (may be used with 
+    or without --auto-hosts)
     """
 )
 parser.add_argument(

sshuttle/sdnotify.py

@@ -16,7 +16,7 @@ def _notify(message):
         debug1("Error creating socket to notify systemd: %s\n" % e)
         return False
 
-    if not message: 
+    if not message:
         return False
 
     assert isinstance(message, bytes)

sshuttle/ssh.py

@@ -69,7 +69,7 @@ def connect(ssh_cmd, rhostport, python, stderr, options):
             rhost = result[0].strip('[')
             if len(result) > 1:
                 result[1] = result[1].strip(':')
-                if result[1] is not '':
+                if result[1] != '':
                     portl = ['-p', str(int(result[1]))]
         # can't disambiguate IPv6 colons and a port number. pass the hostname
         # through.

sshuttle/ssnet.py

@@ -271,7 +271,7 @@ class Handler:
 
     def callback(self, sock):
         log('--no callback defined-- %r\n' % self)
-        (r, w, x) = select.select(self.socks, [], [], 0)
+        (r, _, _) = select.select(self.socks, [], [], 0)
         for s in r:
             v = s.recv(4096)
             if not v:
@@ -350,7 +350,7 @@ class Mux(Handler):
 
     def next_channel(self):
         # channel 0 is special, so we never allocate it
-        for timeout in range(1024):
+        for _ in range(1024):
             self.chani += 1
             if self.chani > MAX_CHANNEL:
                 self.chani = 1
@@ -479,7 +479,7 @@ class Mux(Handler):
             _add(w, self.wsock)
 
     def callback(self, sock):
-        (r, w, x) = select.select([self.rsock], [self.wsock], [], 0)
+        (r, w, _) = select.select([self.rsock], [self.wsock], [], 0)
         if self.rsock in r:
             self.handle()
         if self.outbuf and self.wsock in w:

sshuttle/tests/client/test_options.py

@@ -51,7 +51,7 @@ def test_parse_subnetport_ip4_with_port():
     for ip_repr, ip in _ip4_reprs.items():
         assert sshuttle.options.parse_subnetport(':'.join((ip_repr, '80'))) \
                 == (socket.AF_INET, ip, 32, 80, 80)
-        assert sshuttle.options.parse_subnetport(':'.join((ip_repr, '80-90'))) \
+        assert sshuttle.options.parse_subnetport(':'.join((ip_repr, '80-90')))\
                 == (socket.AF_INET, ip, 32, 80, 90)
 
 
@@ -97,5 +97,5 @@ def test_parse_subnetport_ip6_with_mask_and_port():
     for ip_repr, ip in _ip6_reprs.items():
         assert sshuttle.options.parse_subnetport('[' + ip_repr + '/128]:80') \
                 == (socket.AF_INET6, ip, 128, 80, 80)
-        assert sshuttle.options.parse_subnetport('[' + ip_repr + '/16]:80-90') \
+        assert sshuttle.options.parse_subnetport('[' + ip_repr + '/16]:80-90')\
                 == (socket.AF_INET6, ip, 16, 80, 90)

sshuttle/tests/client/test_sdnotify.py

 from mock import Mock, patch, call
-import sys
-import io
 import socket
 
 import sshuttle.sdnotify
@@ -59,7 +57,7 @@ def test_notify(mock_get, mock_socket):
     sock.sendto.return_value = 1
     mock_get.return_value = '/run/valid_path'
     mock_socket.return_value = sock
-    
+
     assert sshuttle.sdnotify.send(*messages)
     assert sock.sendto.mock_calls == [
         call(b'\n'.join(messages), socket_path),

sshuttle/tests/server/test_server.py

-import os
 import io
 import socket
 import sshuttle.server
-from mock import patch, Mock, call
+from mock import patch, Mock
 
 
 def test__ipmatch():