1#!/usr/bin/env python
2#
3# Copyright (c) 2012, Intel Corporation
4#
5# Author: Johannes Berg <johannes@sipsolutions.net>
6#
7# This software may be distributed under the terms of the BSD license.
8# See README for more details.
9
10import sys, struct, re
11
12def write_pcap_header(pcap_file):
13    pcap_file.write(
14        struct.pack('<IHHIIII',
15                    0xa1b2c3d4, 2, 4, 0, 0, 65535,
16                    105 # raw 802.11 format
17                    ))
18
19def pcap_addpacket(pcap_file, ts, data):
20    # ts in seconds, float
21    pcap_file.write(struct.pack('<IIII',
22        int(ts), int(1000000 * ts) % 1000000,
23        len(data), len(data)))
24    pcap_file.write(data)
25
26if __name__ == "__main__":
27    try:
28        input = sys.argv[1]
29        pcap = sys.argv[2]
30    except IndexError:
31        print("Usage: %s <log file> <pcap file>" % sys.argv[0])
32        sys.exit(2)
33
34    input_file = open(input, 'r')
35    pcap_file = open(pcap, 'w')
36    frame_re = re.compile(r'(([0-9]+.[0-9]{6}):\s*)?nl80211: MLME event frame - hexdump\(len=[0-9]*\):((\s*[0-9a-fA-F]{2})*)')
37
38    write_pcap_header(pcap_file)
39
40    for line in input_file:
41        m = frame_re.match(line)
42        if m is None:
43            continue
44        if m.group(2):
45            ts = float(m.group(2))
46        else:
47            ts = 0
48        hexdata = m.group(3)
49        hexdata = hexdata.split()
50        data = ''.join([chr(int(x, 16)) for x in hexdata])
51        pcap_addpacket(pcap_file, ts, data)
52
53    input_file.close()
54    pcap_file.close()
55