mitmproxy/netlib/socks.py
Aldo Cortesi f2bc58cdd2 Add tcp.Reader.safe_read, use it in socks and websockets
safe_read is guaranteed to raise or return a byte string of the
requested length. It's particularly useful for implementing binary
protocols.
2015-05-05 10:47:02 +12:00

140 lines
3.7 KiB
Python

from __future__ import (absolute_import, print_function, division)
import socket
import struct
import array
from . import tcp, utils
class SocksError(Exception):
def __init__(self, code, message):
super(SocksError, self).__init__(message)
self.code = code
VERSION = utils.BiDi(
SOCKS4 = 0x04,
SOCKS5 = 0x05
)
CMD = utils.BiDi(
CONNECT = 0x01,
BIND = 0x02,
UDP_ASSOCIATE = 0x03
)
ATYP = utils.BiDi(
IPV4_ADDRESS = 0x01,
DOMAINNAME = 0x03,
IPV6_ADDRESS = 0x04
)
REP = utils.BiDi(
SUCCEEDED = 0x00,
GENERAL_SOCKS_SERVER_FAILURE = 0x01,
CONNECTION_NOT_ALLOWED_BY_RULESET = 0x02,
NETWORK_UNREACHABLE = 0x03,
HOST_UNREACHABLE = 0x04,
CONNECTION_REFUSED = 0x05,
TTL_EXPIRED = 0x06,
COMMAND_NOT_SUPPORTED = 0x07,
ADDRESS_TYPE_NOT_SUPPORTED = 0x08,
)
METHOD = utils.BiDi(
NO_AUTHENTICATION_REQUIRED = 0x00,
GSSAPI = 0x01,
USERNAME_PASSWORD = 0x02,
NO_ACCEPTABLE_METHODS = 0xFF
)
class ClientGreeting(object):
__slots__ = ("ver", "methods")
def __init__(self, ver, methods):
self.ver = ver
self.methods = methods
@classmethod
def from_file(cls, f):
ver, nmethods = struct.unpack("!BB", f.safe_read(2))
methods = array.array("B")
methods.fromstring(f.safe_read(nmethods))
return cls(ver, methods)
def to_file(self, f):
f.write(struct.pack("!BB", self.ver, len(self.methods)))
f.write(self.methods.tostring())
class ServerGreeting(object):
__slots__ = ("ver", "method")
def __init__(self, ver, method):
self.ver = ver
self.method = method
@classmethod
def from_file(cls, f):
ver, method = struct.unpack("!BB", f.safe_read(2))
return cls(ver, method)
def to_file(self, f):
f.write(struct.pack("!BB", self.ver, self.method))
class Message(object):
__slots__ = ("ver", "msg", "atyp", "addr")
def __init__(self, ver, msg, atyp, addr):
self.ver = ver
self.msg = msg
self.atyp = atyp
self.addr = addr
@classmethod
def from_file(cls, f):
ver, msg, rsv, atyp = struct.unpack("!BBBB", f.safe_read(4))
if rsv != 0x00:
raise SocksError(REP.GENERAL_SOCKS_SERVER_FAILURE,
"Socks Request: Invalid reserved byte: %s" % rsv)
if atyp == ATYP.IPV4_ADDRESS:
# We use tnoa here as ntop is not commonly available on Windows.
host = socket.inet_ntoa(f.safe_read(4))
use_ipv6 = False
elif atyp == ATYP.IPV6_ADDRESS:
host = socket.inet_ntop(socket.AF_INET6, f.safe_read(16))
use_ipv6 = True
elif atyp == ATYP.DOMAINNAME:
length, = struct.unpack("!B", f.safe_read(1))
host = f.safe_read(length)
use_ipv6 = False
else:
raise SocksError(REP.ADDRESS_TYPE_NOT_SUPPORTED,
"Socks Request: Unknown ATYP: %s" % atyp)
port, = struct.unpack("!H", f.safe_read(2))
addr = tcp.Address((host, port), use_ipv6=use_ipv6)
return cls(ver, msg, atyp, addr)
def to_file(self, f):
f.write(struct.pack("!BBBB", self.ver, self.msg, 0x00, self.atyp))
if self.atyp == ATYP.IPV4_ADDRESS:
f.write(socket.inet_aton(self.addr.host))
elif self.atyp == ATYP.IPV6_ADDRESS:
f.write(socket.inet_pton(socket.AF_INET6, self.addr.host))
elif self.atyp == ATYP.DOMAINNAME:
f.write(struct.pack("!B", len(self.addr.host)))
f.write(self.addr.host)
else:
raise SocksError(
REP.ADDRESS_TYPE_NOT_SUPPORTED,
"Unknown ATYP: %s" % self.atyp
)
f.write(struct.pack("!H", self.addr.port))