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
233
234
235
236
237
238
239
240
241
242
243
244
245
|
import random
import string
import typing # noqa
import pyparsing as pp
import mitmproxy.net.websockets
from mitmproxy.utils import strutils
from . import base, generators, actions, message
NESTED_LEADER = b"pathod!"
class WF(base.CaselessLiteral):
TOK = "wf"
class OpCode(base.IntField):
names = {
"continue": mitmproxy.net.websockets.OPCODE.CONTINUE,
"text": mitmproxy.net.websockets.OPCODE.TEXT,
"binary": mitmproxy.net.websockets.OPCODE.BINARY,
"close": mitmproxy.net.websockets.OPCODE.CLOSE,
"ping": mitmproxy.net.websockets.OPCODE.PING,
"pong": mitmproxy.net.websockets.OPCODE.PONG,
} # type: typing.Dict[str, int]
max = 15
preamble = "c"
class Body(base.Value):
preamble = "b"
class RawBody(base.Value):
unique_name = "body"
preamble = "r"
class Fin(base.Boolean):
name = "fin"
class RSV1(base.Boolean):
name = "rsv1"
class RSV2(base.Boolean):
name = "rsv2"
class RSV3(base.Boolean):
name = "rsv3"
class Mask(base.Boolean):
name = "mask"
class Key(base.FixedLengthValue):
preamble = "k"
length = 4
class KeyNone(base.CaselessLiteral):
unique_name = "key"
TOK = "knone"
class Length(base.Integer):
bounds = (0, 1 << 64)
preamble = "l"
class Times(base.Integer):
preamble = "x"
COMPONENTS = [
OpCode,
Length,
# Bit flags
Fin,
RSV1,
RSV2,
RSV3,
Mask,
actions.PauseAt,
actions.DisconnectAt,
actions.InjectAt,
KeyNone,
Key,
Times,
Body,
RawBody,
]
class WebsocketFrame(message.Message):
components = COMPONENTS # type: typing.List[typing.Type[base._Component]]
logattrs = ["body"]
# Used for nested frames
unique_name = "body"
@property
def actions(self):
return self.toks(actions._Action)
@property
def body(self):
return self.tok(Body)
@property
def rawbody(self):
return self.tok(RawBody)
@property
def opcode(self):
return self.tok(OpCode)
@property
def fin(self):
return self.tok(Fin)
@property
def rsv1(self):
return self.tok(RSV1)
@property
def rsv2(self):
return self.tok(RSV2)
@property
def rsv3(self):
return self.tok(RSV3)
@property
def mask(self):
return self.tok(Mask)
@property
def key(self):
return self.tok(Key)
@property
def knone(self):
return self.tok(KeyNone)
@property
def times(self):
return self.tok(Times)
@property
def toklength(self):
return self.tok(Length)
@classmethod
def expr(cls):
parts = [i.expr() for i in cls.components]
atom = pp.MatchFirst(parts)
resp = pp.And(
[
WF.expr(),
base.Sep,
pp.ZeroOrMore(base.Sep + atom)
]
)
resp = resp.setParseAction(cls)
return resp
@property
def nested_frame(self):
return self.tok(NestedFrame)
def resolve(self, settings, msg=None):
tokens = self.tokens[:]
if not self.mask and settings.is_client:
tokens.append(
Mask(True)
)
if not self.knone and self.mask and self.mask.value and not self.key:
allowed_chars = string.ascii_letters + string.digits
k = ''.join([allowed_chars[random.randrange(0, len(allowed_chars))] for i in range(4)])
tokens.append(
Key(base.TokValueLiteral(k))
)
return self.__class__(
[i.resolve(settings, self) for i in tokens]
)
def values(self, settings):
if self.body:
bodygen = self.body.value.get_generator(settings)
length = len(self.body.value.get_generator(settings))
elif self.rawbody:
bodygen = self.rawbody.value.get_generator(settings)
length = len(self.rawbody.value.get_generator(settings))
elif self.nested_frame:
bodygen = NESTED_LEADER + strutils.always_bytes(self.nested_frame.parsed.spec())
length = len(bodygen)
else:
bodygen = None
length = 0
if self.toklength:
length = int(self.toklength.value)
frameparts = dict(
payload_length=length
)
if self.mask and self.mask.value:
frameparts["mask"] = True
if self.knone:
frameparts["masking_key"] = None
elif self.key:
key = self.key.values(settings)[0][:]
frameparts["masking_key"] = key
for i in ["opcode", "fin", "rsv1", "rsv2", "rsv3", "mask"]:
v = getattr(self, i, None)
if v is not None:
frameparts[i] = v.value
frame = mitmproxy.net.websockets.FrameHeader(**frameparts)
vals = [bytes(frame)]
if bodygen:
if frame.masking_key and not self.rawbody:
masker = mitmproxy.net.websockets.Masker(frame.masking_key)
vals.append(
generators.TransformGenerator(
bodygen,
masker.mask
)
)
else:
vals.append(bodygen)
return vals
def spec(self):
return ":".join([i.spec() for i in self.tokens])
class NestedFrame(base.NestedMessage):
preamble = "f"
nest_type = WebsocketFrame
class WebsocketClientFrame(WebsocketFrame):
components = COMPONENTS + [NestedFrame]
|
