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
|
# $Id: diameter.py 23 2006-11-08 15:45:33Z dugsong $
# -*- coding: utf-8 -*-
"""Diameter."""
from __future__ import print_function
from __future__ import absolute_import
import struct
from . import dpkt
from .compat import compat_ord
# Diameter Base Protocol - RFC 3588
# http://tools.ietf.org/html/rfc3588
# Request/Answer Command Codes
ABORT_SESSION = 274
ACCOUNTING = 271
CAPABILITIES_EXCHANGE = 257
DEVICE_WATCHDOG = 280
DISCONNECT_PEER = 282
RE_AUTH = 258
SESSION_TERMINATION = 275
class Diameter(dpkt.Packet):
"""Diameter.
Diameter is an authentication, authorization, and accounting protocol for computer networks. It evolved from the
earlier RADIUS protocol. It belongs to the application layer protocols in the internet protocol suite.
Attributes:
__hdr__: Header fields of Diameter.
v: (int) Version. The version of the Diameter Base Protocol.
As of 2014, the only value supported is 1. (1 byte)
len: (bytes): Message Length. The Message Length field indicates the length of the Diameter message in
bytes, including the header fields and the padded AVPs. (3 bytes)
flags: (int): Command flags. (Request, Proxiable, Error, Potentially re-transmitted message) (1 byte)
cmd: (bytes): Commands. Determine the action that is to be taken for a particular message. (3 bytes)
app_id: (int): Application-ID. Application-ID is used to identify for which Diameter application the
message is applicable. (4 bytes)
hop_id: (int): Hop-by-Hop Identifier. Used to match the requests with their answers as the same value in
the request is used in the response. (4 bytes)
end_id: (int): End-to-End Identifier. used to detect duplicate messages along with the combination of the
Origin-Host AVP. (4 bytes)
"""
__hdr__ = (
('v', 'B', 1),
('len', '3s', 0),
('flags', 'B', 0),
('cmd', '3s', 0),
('app_id', 'I', 0),
('hop_id', 'I', 0),
('end_id', 'I', 0)
)
@property
def request_flag(self):
return (self.flags >> 7) & 0x1
@request_flag.setter
def request_flag(self, r):
self.flags = (self.flags & ~0x80) | ((r & 0x1) << 7)
@property
def proxiable_flag(self):
return (self.flags >> 6) & 0x1
@proxiable_flag.setter
def proxiable_flag(self, p):
self.flags = (self.flags & ~0x40) | ((p & 0x1) << 6)
@property
def error_flag(self):
return (self.flags >> 5) & 0x1
@error_flag.setter
def error_flag(self, e):
self.flags = (self.flags & ~0x20) | ((e & 0x1) << 5)
@property
def retransmit_flag(self):
return (self.flags >> 4) & 0x1
@retransmit_flag.setter
def retransmit_flag(self, t):
self.flags = (self.flags & ~0x10) | ((t & 0x1) << 4)
def unpack(self, buf):
dpkt.Packet.unpack(self, buf)
self.cmd = (compat_ord(self.cmd[0]) << 16) | \
(compat_ord(self.cmd[1]) << 8) | \
(compat_ord(self.cmd[2]))
self.len = (compat_ord(self.len[0]) << 16) | \
(compat_ord(self.len[1]) << 8) | \
(compat_ord(self.len[2]))
self.data = self.data[:self.len - self.__hdr_len__]
l_ = []
while self.data:
avp = AVP(self.data)
l_.append(avp)
self.data = self.data[len(avp):]
self.data = self.avps = l_
def pack_hdr(self):
self.len = struct.pack("BBB", (self.len >> 16) & 0xff, (self.len >> 8) & 0xff, self.len & 0xff)
self.cmd = struct.pack("BBB", (self.cmd >> 16) & 0xff, (self.cmd >> 8) & 0xff, self.cmd & 0xff)
return dpkt.Packet.pack_hdr(self)
def __len__(self):
return self.__hdr_len__ + sum(map(len, self.data))
def __bytes__(self):
return self.pack_hdr() + b''.join(map(bytes, self.data))
class AVP(dpkt.Packet):
__hdr__ = (
('code', 'I', 0),
('flags', 'B', 0),
('len', '3s', 0),
)
@property
def vendor_flag(self):
return (self.flags >> 7) & 0x1
@vendor_flag.setter
def vendor_flag(self, v):
self.flags = (self.flags & ~0x80) | ((v & 0x1) << 7)
@property
def mandatory_flag(self):
return (self.flags >> 6) & 0x1
@mandatory_flag.setter
def mandatory_flag(self, m):
self.flags = (self.flags & ~0x40) | ((m & 0x1) << 6)
@property
def protected_flag(self):
return (self.flags >> 5) & 0x1
@protected_flag.setter
def protected_flag(self, p):
self.flags = (self.flags & ~0x20) | ((p & 0x1) << 5)
def unpack(self, buf):
dpkt.Packet.unpack(self, buf)
self.len = (compat_ord(self.len[0]) << 16) | \
(compat_ord(self.len[1]) << 8) | \
(compat_ord(self.len[2]))
if self.vendor_flag:
self.vendor = struct.unpack('>I', self.data[:4])[0]
self.data = self.data[4:self.len - self.__hdr_len__]
else:
self.data = self.data[:self.len - self.__hdr_len__]
def pack_hdr(self):
self.len = struct.pack("BBB", (self.len >> 16) & 0xff, (self.len >> 8) & 0xff, self.len & 0xff)
data = dpkt.Packet.pack_hdr(self)
if self.vendor_flag:
data += struct.pack('>I', self.vendor)
return data
def __len__(self):
length = self.__hdr_len__ + len(self.data)
if self.vendor_flag:
length += 4
return length
__s = (b'\x01\x00\x00\x28\x80\x00\x01\x18\x00\x00\x00\x00\x00\x00\x41\xc8\x00\x00\x00\x0c\x00\x00'
b'\x01\x08\x40\x00\x00\x0c\x68\x30\x30\x32\x00\x00\x01\x28\x40\x00\x00\x08')
__t = (b'\x01\x00\x00\x2c\x80\x00\x01\x18\x00\x00\x00\x00\x00\x00\x41\xc8\x00\x00\x00\x0c\x00\x00'
b'\x01\x08\xc0\x00\x00\x10\xde\xad\xbe\xef\x68\x30\x30\x32\x00\x00\x01\x28\x40\x00\x00\x08')
def test_pack():
d = Diameter(__s)
assert (__s == bytes(d))
assert len(d) == len(__s)
d = Diameter(__t)
assert (__t == bytes(d))
assert len(d) == len(__t)
def test_unpack():
d = Diameter(__s)
assert (d.len == 40)
# assert (d.cmd == DEVICE_WATCHDOG_REQUEST)
assert (d.request_flag == 1)
assert (d.error_flag == 0)
assert (len(d.avps) == 2)
avp = d.avps[0]
# assert (avp.code == ORIGIN_HOST)
assert (avp.mandatory_flag == 1)
assert (avp.vendor_flag == 0)
assert (avp.len == 12)
assert (len(avp) == 12)
assert (avp.data == b'\x68\x30\x30\x32')
# also test the optional vendor id support
d = Diameter(__t)
assert (d.len == 44)
avp = d.avps[0]
assert (avp.vendor_flag == 1)
assert (avp.len == 16)
assert (len(avp) == 16)
assert (avp.vendor == 3735928559)
assert (avp.data == b'\x68\x30\x30\x32')
def test_diameter_properties():
diameter = Diameter()
for prop in ['request_flag', 'proxiable_flag', 'error_flag', 'retransmit_flag']:
assert hasattr(diameter, prop)
assert getattr(diameter, prop) == 0
setattr(diameter, prop, 1)
assert getattr(diameter, prop) == 1
def test_avp_properties():
avp = AVP()
for prop in ['vendor_flag', 'mandatory_flag', 'protected_flag']:
assert hasattr(avp, prop)
assert getattr(avp, prop) == 0
setattr(avp, prop, 1)
assert getattr(avp, prop) == 1
|
