1
2 // Author: Michael Mehari
3 // SPDX-FileCopyrightText: 2020 UGent
4 // SPDX-License-Identifier: GPL-2.0-or-later
5
6 /*
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; version 2.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License along
17 * with this program; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19 */
20
21 #include "inject_80211.h"
22 #include "radiotap.h"
23 #include "uthash.h"
24
25 #define HEADERLEN_80211 24
26
27 struct RECORD_t
28 {
29 char id[16]; // hw_mode-rate-sgi_flag-packet_size
30 uint16_t pkt_cnt; // number of packets received
31 uint64_t ts_begin; // beginning timestamp
32 uint64_t ts_end; // ending timestamp
33
34 UT_hash_handle hh; // hash function handler
35 };
36
37 /* 802.11n bitrates x 2 */
38 static const uint8_t rates_11n[] = {13, 26, 39, 52, 78, 104, 117, 130};
39
main(int argc,char ** argv)40 int main(int argc, char **argv)
41 {
42 struct pcap_pkthdr pcap_hdr;
43 const u_char *packet;
44 char hw_mode, id[16];
45 int rate, sgi_flag, packet_size;
46
47 int n, hdr_len;
48 struct ieee80211_radiotap_iterator rti;
49
50 struct RECORD_t *RECORD_ptr, *tmp_ptr, *hash_ptr = NULL;
51
52 if (argc < 2)
53 {
54 fprintf(stderr, "Usage: %s <pcap>\n", argv[0]);
55 exit(1);
56 }
57
58 pcap_t *handle;
59 char errbuf[PCAP_ERRBUF_SIZE];
60 handle = pcap_open_offline(argv[1], errbuf);
61
62 if (handle == NULL)
63 {
64 fprintf(stderr,"Couldn't open pcap file %s: %s\n", argv[1], errbuf);
65 return(2);
66 }
67
68 while ((packet = pcap_next(handle, &pcap_hdr)))
69 {
70 hdr_len = (packet[2] + (packet[3] << 8));
71 if (pcap_hdr.len < (hdr_len + HEADERLEN_80211))
72 continue;
73
74 packet_size = pcap_hdr.len - (hdr_len + HEADERLEN_80211);
75 if (packet_size < 0)
76 continue;
77
78 if (ieee80211_radiotap_iterator_init(&rti, (struct ieee80211_radiotap_header *)packet, packet_size, NULL) < 0)
79 continue;
80
81 while ((n = ieee80211_radiotap_iterator_next(&rti)) == 0)
82 {
83 switch (rti.this_arg_index)
84 {
85 case IEEE80211_RADIOTAP_RATE:
86 rate = (rti.this_arg)[0];
87 sgi_flag = 0;
88 hw_mode = 'a';
89 break;
90
91 case IEEE80211_RADIOTAP_MCS:
92 rate = rates_11n[((rti.this_arg)[2])];
93 sgi_flag = (rti.this_arg)[1] & 0x40;
94 hw_mode = 'n';
95 break;
96 }
97 }
98
99 // create hash table index
100 sprintf(id, "%c-%d-%d-%d", hw_mode, rate, sgi_flag, packet_size);
101
102 // Hash table implementation for c : https://github.com/troydhanson/uthash
103 HASH_FIND_STR(hash_ptr, id, RECORD_ptr);
104 if(RECORD_ptr == NULL)
105 {
106 RECORD_ptr = (struct RECORD_t*)malloc(sizeof(struct RECORD_t));
107 if(RECORD_ptr == NULL)
108 {
109 fprintf(stderr, "Unable to create record!\n");
110 return 1;
111 }
112
113 strcpy(RECORD_ptr->id, id);
114 RECORD_ptr->pkt_cnt = 1;
115 RECORD_ptr->ts_begin = 1e6*pcap_hdr.ts.tv_sec + pcap_hdr.ts.tv_usec;
116
117 // Add the new record to the hash table
118 HASH_ADD_STR(hash_ptr, id, RECORD_ptr);
119 }
120 else
121 {
122 RECORD_ptr->pkt_cnt++;
123 RECORD_ptr->ts_end = 1e6*pcap_hdr.ts.tv_sec + pcap_hdr.ts.tv_usec;
124 }
125 }
126 pcap_close(handle);
127
128
129 // Iterate through the hash table
130 printf("HW MODE\tRATE(Mbps)\tSGI\tSIZE(bytes)\tCOUNT\tDELAY(sec)\n");
131 printf("=======\t==========\t===\t===========\t=====\t=========\n");
132 HASH_ITER(hh, hash_ptr, RECORD_ptr, tmp_ptr)
133 {
134 sscanf(RECORD_ptr->id, "%c-%d-%d-%d", &hw_mode, &rate, &sgi_flag, &packet_size);
135 printf("802.11%c\t%.1f\t\t%s\t%d\t\t%d\t%.5f\n", hw_mode, rate/2.0, (sgi_flag == 0 ? "OFF" : "ON"), packet_size, RECORD_ptr->pkt_cnt, 1e-6*(RECORD_ptr->ts_end - RECORD_ptr->ts_begin));
136 }
137 fflush(stdout);
138
139 return 0;
140 }
141