summaryrefslogtreecommitdiffstats
path: root/scripts/external_libs/dpkt-1.8.6.2/dpkt/ah.py
blob: 5ad29ad5a19732d42ec32b8a795a761344f4c5d4 (plain)
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
# $Id: ah.py 34 2007-01-28 07:54:20Z dugsong $
# -*- coding: utf-8 -*-

"""Authentication Header."""

import dpkt


class AH(dpkt.Packet):
    __hdr__ = (
        ('nxt', 'B', 0),
        ('len', 'B', 0),  # payload length
        ('rsvd', 'H', 0),
        ('spi', 'I', 0),
        ('seq', 'I', 0)
    )
    auth = ''

    def unpack(self, buf):
        dpkt.Packet.unpack(self, buf)
        self.auth = self.data[:self.len]
        buf = self.data[self.len:]
        import ip

        try:
            self.data = ip.IP.get_proto(self.nxt)(buf)
            setattr(self, self.data.__class__.__name__.lower(), self.data)
        except (KeyError, dpkt.UnpackError):
            self.data = buf

    def __len__(self):
        return self.__hdr_len__ + len(self.auth) + len(self.data)

    def __str__(self):
        return self.pack_hdr() + str(self.auth) + str(self.data)