1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
from __future__ import (absolute_import, print_function, division)
import struct
import array
import ipaddress
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
)
USERNAME_PASSWORD_VERSION = utils.BiDi(
DEFAULT=0x01
)
class ClientGreeting(object):
__slots__ = ("ver", "methods")
def __init__(self, ver, methods):
self.ver = ver
self.methods = array.array("B")
self.methods.extend(methods)
def assert_socks5(self):
if self.ver != VERSION.SOCKS5:
if self.ver == ord("G") and len(self.methods) == ord("E"):
guess = "Probably not a SOCKS request but a regular HTTP request. "
else:
guess = ""
raise SocksError(
REP.GENERAL_SOCKS_SERVER_FAILURE,
guess + "Invalid SOCKS version. Expected 0x05, got 0x%x" % self.ver
)
@classmethod
def from_file(cls, f, fail_early=False):
"""
:param fail_early: If true, a SocksError will be raised if the first byte does not indicate socks5.
"""
ver, nmethods = struct.unpack("!BB", f.safe_read(2))
client_greeting = cls(ver, [])
if fail_early:
client_greeting.assert_socks5()
client_greeting.methods.fromstring(f.safe_read(nmethods))
return client_greeting
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
def assert_socks5(self):
if self.ver != VERSION.SOCKS5:
if self.ver == ord("H") and self.method == ord("T"):
guess = "Probably not a SOCKS request but a regular HTTP response. "
else:
guess = ""
raise SocksError(
REP.GENERAL_SOCKS_SERVER_FAILURE,
guess + "Invalid SOCKS version. Expected 0x05, got 0x%x" % self.ver
)
@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 UsernamePasswordAuth(object):
__slots__ = ("ver", "username", "password")
def __init__(self, ver, username, password):
self.ver = ver
self.username = username
self.password = password
def assert_authver1(self):
if self.ver != USERNAME_PASSWORD_VERSION.DEFAULT:
raise SocksError(
0,
"Invalid auth version. Expected 0x01, got 0x%x" % self.ver
)
@classmethod
def from_file(cls, f):
ver, ulen = struct.unpack("!BB", f.safe_read(2))
username = f.safe_read(ulen)
plen, = struct.unpack("!B", f.safe_read(1))
password = f.safe_read(plen)
return cls(ver, username.decode(), password.decode())
def to_file(self, f):
f.write(struct.pack("!BB", self.ver, len(self.username)))
f.write(self.username.encode())
f.write(struct.pack("!B", len(self.password)))
f.write(self.password.encode())
class UsernamePasswordAuthResponse(object):
__slots__ = ("ver", "status")
def __init__(self, ver, status):
self.ver = ver
self.status = status
def assert_authver1(self):
if self.ver != USERNAME_PASSWORD_VERSION.DEFAULT:
raise SocksError(
0,
"Invalid auth version. Expected 0x01, got 0x%x" % self.ver
)
@classmethod
def from_file(cls, f):
ver, status = struct.unpack("!BB", f.safe_read(2))
return cls(ver, status)
def to_file(self, f):
f.write(struct.pack("!BB", self.ver, self.status))
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 = tcp.Address.wrap(addr)
def assert_socks5(self):
if self.ver != VERSION.SOCKS5:
raise SocksError(
REP.GENERAL_SOCKS_SERVER_FAILURE,
"Invalid SOCKS version. Expected 0x05, got 0x%x" % self.ver
)
@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 = ipaddress.IPv4Address(f.safe_read(4)).compressed
use_ipv6 = False
elif atyp == ATYP.IPV6_ADDRESS:
host = ipaddress.IPv6Address(f.safe_read(16)).compressed
use_ipv6 = True
elif atyp == ATYP.DOMAINNAME:
length, = struct.unpack("!B", f.safe_read(1))
host = f.safe_read(length)
if not utils.is_valid_host(host):
raise SocksError(REP.GENERAL_SOCKS_SERVER_FAILURE, "Invalid hostname: %s" % host)
host = host.decode("idna")
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(ipaddress.IPv4Address(self.addr.host).packed)
elif self.atyp == ATYP.IPV6_ADDRESS:
f.write(ipaddress.IPv6Address(self.addr.host).packed)
elif self.atyp == ATYP.DOMAINNAME:
f.write(struct.pack("!B", len(self.addr.host)))
f.write(self.addr.host.encode("idna"))
else:
raise SocksError(
REP.ADDRESS_TYPE_NOT_SUPPORTED,
"Unknown ATYP: %s" % self.atyp
)
f.write(struct.pack("!H", self.addr.port))
|
