test/functional/test_framework/socks5.py

   1 #!/usr/bin/env python3
   2 # Copyright (c) 2015-2016 The Bitcoin Core developers
   3 # Distributed under the MIT software license, see the accompanying
   4 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5 """Dummy Socks5 server for testing."""
   6
   7 import socket, threading, queue
   8 import logging
   9
  10 logger = logging.getLogger("TestFramework.socks5")
  11
  12 ### Protocol constants
  13 class Command:
  14     CONNECT = 0x01
  15
  16 class AddressType:
  17     IPV4 = 0x01
  18     DOMAINNAME = 0x03
  19     IPV6 = 0x04
  20
  21 ### Utility functions
  22 def recvall(s, n):
  23     """Receive n bytes from a socket, or fail."""
  24     rv = bytearray()
  25     while n > 0:
  26         d = s.recv(n)
  27         if not d:
  28             raise IOError('Unexpected end of stream')
  29         rv.extend(d)
  30         n -= len(d)
  31     return rv
  32
  33 ### Implementation classes
  34 class Socks5Configuration():
  35     """Proxy configuration."""
  36     def __init__(self):
  37         self.addr = None # Bind address (must be set)
  38         self.af = socket.AF_INET # Bind address family
  39         self.unauth = False  # Support unauthenticated
  40         self.auth = False  # Support authentication
  41
  42 class Socks5Command():
  43     """Information about an incoming socks5 command."""
  44     def __init__(self, cmd, atyp, addr, port, username, password):
  45         self.cmd = cmd # Command (one of Command.*)
  46         self.atyp = atyp # Address type (one of AddressType.*)
  47         self.addr = addr # Address
  48         self.port = port # Port to connect to
  49         self.username = username
  50         self.password = password
  51     def __repr__(self):
  52         return 'Socks5Command(%s,%s,%s,%s,%s,%s)' % (self.cmd, self.atyp, self.addr, self.port, self.username, self.password)
  53
  54 class Socks5Connection():
  55     def __init__(self, serv, conn, peer):
  56         self.serv = serv
  57         self.conn = conn
  58         self.peer = peer
  59
  60     def handle(self):
  61         """Handle socks5 request according to RFC192."""
  62         try:
  63             # Verify socks version
  64             ver = recvall(self.conn, 1)[0]
  65             if ver != 0x05:
  66                 raise IOError('Invalid socks version %i' % ver)
  67             # Choose authentication method
  68             nmethods = recvall(self.conn, 1)[0]
  69             methods = bytearray(recvall(self.conn, nmethods))
  70             method = None
  71             if 0x02 in methods and self.serv.conf.auth:
  72                 method = 0x02 # username/password
  73             elif 0x00 in methods and self.serv.conf.unauth:
  74                 method = 0x00 # unauthenticated
  75             if method is None:
  76                 raise IOError('No supported authentication method was offered')
  77             # Send response
  78             self.conn.sendall(bytearray([0x05, method]))
  79             # Read authentication (optional)
  80             username = None
  81             password = None
  82             if method == 0x02:
  83                 ver = recvall(self.conn, 1)[0]
  84                 if ver != 0x01:
  85                     raise IOError('Invalid auth packet version %i' % ver)
  86                 ulen = recvall(self.conn, 1)[0]
  87                 username = str(recvall(self.conn, ulen))
  88                 plen = recvall(self.conn, 1)[0]
  89                 password = str(recvall(self.conn, plen))
  90                 # Send authentication response
  91                 self.conn.sendall(bytearray([0x01, 0x00]))
  92
  93             # Read connect request
  94             ver, cmd, _, atyp = recvall(self.conn, 4)
  95             if ver != 0x05:
  96                 raise IOError('Invalid socks version %i in connect request' % ver)
  97             if cmd != Command.CONNECT:
  98                 raise IOError('Unhandled command %i in connect request' % cmd)
  99
 100             if atyp == AddressType.IPV4:
 101                 addr = recvall(self.conn, 4)
 102             elif atyp == AddressType.DOMAINNAME:
 103                 n = recvall(self.conn, 1)[0]
 104                 addr = recvall(self.conn, n)
 105             elif atyp == AddressType.IPV6:
 106                 addr = recvall(self.conn, 16)
 107             else:
 108                 raise IOError('Unknown address type %i' % atyp)
 109             port_hi,port_lo = recvall(self.conn, 2)
 110             port = (port_hi << 8) | port_lo
 111
 112             # Send dummy response
 113             self.conn.sendall(bytearray([0x05, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]))
 114
 115             cmdin = Socks5Command(cmd, atyp, addr, port, username, password)
 116             self.serv.queue.put(cmdin)
 117             logger.info('Proxy: %s', cmdin)
 118             # Fall through to disconnect
 119         except Exception as e:
 120             logger.exception("socks5 request handling failed.")
 121             self.serv.queue.put(e)
 122         finally:
 123             self.conn.close()
 124
 125 class Socks5Server():
 126     def __init__(self, conf):
 127         self.conf = conf
 128         self.s = socket.socket(conf.af)
 129         self.s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
 130         self.s.bind(conf.addr)
 131         self.s.listen(5)
 132         self.running = False
 133         self.thread = None
 134         self.queue = queue.Queue() # report connections and exceptions to client
 135
 136     def run(self):
 137         while self.running:
 138             (sockconn, peer) = self.s.accept()
 139             if self.running:
 140                 conn = Socks5Connection(self, sockconn, peer)
 141                 thread = threading.Thread(None, conn.handle)
 142                 thread.daemon = True
 143                 thread.start()
 144
 145     def start(self):
 146         assert(not self.running)
 147         self.running = True
 148         self.thread = threading.Thread(None, self.run)
 149         self.thread.daemon = True
 150         self.thread.start()
 151
 152     def stop(self):
 153         self.running = False
 154         # connect to self to end run loop
 155         s = socket.socket(self.conf.af)
 156         s.connect(self.conf.addr)
 157         s.close()
 158         self.thread.join()
 159