mitmproxy/libmproxy/proxy/modes/socks_proxy.py
2015-09-03 17:01:25 +02:00

61 lines
2.2 KiB
Python

from __future__ import (absolute_import, print_function, division)
from netlib import socks
from netlib.tcp import NetLibError
from ...exceptions import Socks5Exception
from ...protocol import Layer, ServerConnectionMixin
class Socks5Proxy(Layer, ServerConnectionMixin):
def __call__(self):
try:
# Parse Client Greeting
client_greet = socks.ClientGreeting.from_file(self.client_conn.rfile, fail_early=True)
client_greet.assert_socks5()
if socks.METHOD.NO_AUTHENTICATION_REQUIRED not in client_greet.methods:
raise socks.SocksError(
socks.METHOD.NO_ACCEPTABLE_METHODS,
"mitmproxy only supports SOCKS without authentication"
)
# Send Server Greeting
server_greet = socks.ServerGreeting(
socks.VERSION.SOCKS5,
socks.METHOD.NO_AUTHENTICATION_REQUIRED
)
server_greet.to_file(self.client_conn.wfile)
self.client_conn.wfile.flush()
# Parse Connect Request
connect_request = socks.Message.from_file(self.client_conn.rfile)
connect_request.assert_socks5()
if connect_request.msg != socks.CMD.CONNECT:
raise socks.SocksError(
socks.REP.COMMAND_NOT_SUPPORTED,
"mitmproxy only supports SOCKS5 CONNECT."
)
# We always connect lazily, but we need to pretend to the client that we connected.
connect_reply = socks.Message(
socks.VERSION.SOCKS5,
socks.REP.SUCCEEDED,
connect_request.atyp,
# dummy value, we don't have an upstream connection yet.
connect_request.addr
)
connect_reply.to_file(self.client_conn.wfile)
self.client_conn.wfile.flush()
except (socks.SocksError, NetLibError) as e:
raise Socks5Exception("SOCKS5 mode failure: %s" % repr(e), e)
self.server_conn.address = connect_request.addr
layer = self.ctx.next_layer(self)
try:
layer()
finally:
if self.server_conn:
self.disconnect()