mitmproxy/libmproxy/proxy/modes/socks_proxy.py

66 lines
2.5 KiB
Python

from __future__ import (absolute_import, print_function, division)
from netlib import socks, tcp
from netlib.exceptions import TcpException
from ...exceptions import Socks5ProtocolException
from ...protocol import Layer, ServerConnectionMixin
class Socks5Proxy(Layer, ServerConnectionMixin):
def __init__(self, ctx):
super(Socks5Proxy, self).__init__(ctx)
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, TcpException) as e:
raise Socks5ProtocolException("SOCKS5 mode failure: %s" % repr(e))
# https://github.com/mitmproxy/mitmproxy/issues/839
address_bytes = (connect_request.addr.host.encode("idna"), connect_request.addr.port)
self.server_conn.address = tcp.Address(address_bytes, connect_request.addr.use_ipv6)
layer = self.ctx.next_layer(self)
try:
layer()
finally:
if self.server_conn:
self.disconnect()