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
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
|
/*
*
* libnet 1.1
* Build a BGP4 update message with what you want as payload
*
* Copyright (c) 2003 Frédéric Raynal <pappy@security-labs.org>
* All rights reserved.
*
* Examples:
*
* empty BGP UPDATE message:
*
* # ./bgp4_update -s 1.1.1.1 -d 2.2.2.2
* libnet 1.1 packet shaping: BGP4 update + payload[raw]
* Wrote 63 byte TCP packet; check the wire.
*
* 13:44:29.216135 1.1.1.1.26214 > 2.2.2.2.179: S [tcp sum ok]
* 16843009:16843032(23) win 32767: BGP (ttl 64, id 242, len 63)
* 0x0000 4500 003f 00f2 0000 4006 73c2 0101 0101 E..?....@.s.....
* 0x0010 0202 0202 6666 00b3 0101 0101 0202 0202 ....ff..........
* 0x0020 5002 7fff b288 0000 0101 0101 0101 0101 P...............
* 0x0030 0101 0101 0101 0101 0017 0200 0000 00 ...............
*
*
* BGP UPDATE with Path Attributes and Unfeasible Routes Length
*
* # ./bgp4_update -s 1.1.1.1 -d 2.2.2.2 -a `printf "\x01\x02\x03"` -A 3 -W 13
* libnet 1.1 packet shaping: BGP4 update + payload[raw]
* Wrote 79 byte TCP packet; check the wire.
*
* 13:45:59.579901 1.1.1.1.26214 > 2.2.2.2.179: S [tcp sum ok]
* 16843009:16843048(39) win 32767: BGP (ttl 64, id 242, len 79)
* 0x0000 4500 004f 00f2 0000 4006 73b2 0101 0101 E..O....@.s.....
* 0x0010 0202 0202 6666 00b3 0101 0101 0202 0202 ....ff..........
* 0x0020 5002 7fff 199b 0000 0101 0101 0101 0101 P...............
* 0x0030 0101 0101 0101 0101 0027 0200 0d41 4141 .........'...AAA
* 0x0040 4141 4141 4141 4141 4141 0003 0102 03 AAAAAAAAAA.....
*
*
* BGP UPDATE with Reachability Information
*
* # ./bgp4_update -s 1.1.1.1 -d 2.2.2.2 -I 7
* libnet 1.1 packet shaping: BGP4 update + payload[raw]
* Wrote 70 byte TCP packet; check the wire.
*
* 13:49:02.829225 1.1.1.1.26214 > 2.2.2.2.179: S [tcp sum ok]
* 16843009:16843039(30) win 32767: BGP (ttl 64, id 242, len 70)
* 0x0000 4500 0046 00f2 0000 4006 73bb 0101 0101 E..F....@.s.....
* 0x0010 0202 0202 6666 00b3 0101 0101 0202 0202 ....ff..........
* 0x0020 5002 7fff e86d 0000 0101 0101 0101 0101 P....m..........
* 0x0030 0101 0101 0101 0101 001e 0200 0000 0043 ...............C
* 0x0040 4343 4343 4343 CCCCCC
*
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#if (HAVE_CONFIG_H)
#include "../include/config.h"
#endif
#include "./libnet_test.h"
#define set_ptr_and_size(ptr, size, val, flag) \
if (size && !ptr) \
{ \
ptr = (u_char *)malloc(size); \
if (!ptr) \
{ \
printf("memory allocation failed (%u bytes requested)\n", size); \
goto bad; \
} \
memset(ptr, val, size); \
flag = 1; \
} \
\
if (ptr && !size) \
{ \
size = strlen((char *)ptr); \
}
int
main(int argc, char *argv[])
{
int c;
libnet_t *l;
u_long src_ip, dst_ip, length;
libnet_ptag_t t = 0;
char errbuf[LIBNET_ERRBUF_SIZE];
u_char *payload = NULL;
u_long payload_s = 0;
u_char marker[LIBNET_BGP4_MARKER_SIZE];
u_short u_rt_l = 0;
u_char *withdraw_rt = NULL;
char flag_w = 0;
u_short attr_l = 0;
u_char *attr = NULL;
char flag_a = 0;
u_short info_l = 0;
u_char *info = NULL;
char flag_i = 0;
printf("libnet 1.1 packet shaping: BGP4 update + payload[raw]\n");
/*
* Initialize the library. Root priviledges are required.
*/
l = libnet_init(
LIBNET_RAW4, /* injection type */
NULL, /* network interface */
errbuf); /* error buffer */
if (l == NULL)
{
fprintf(stderr, "libnet_init() failed: %s", errbuf);
exit(EXIT_FAILURE);
}
src_ip = 0;
dst_ip = 0;
memset(marker, 0x1, LIBNET_BGP4_MARKER_SIZE);
while ((c = getopt(argc, argv, "d:s:t:m:p:w:W:a:A:i:I:")) != EOF)
{
switch (c)
{
/*
* We expect the input to be of the form `ip.ip.ip.ip.port`. We
* point cp to the last dot of the IP address/port string and
* then seperate them with a NULL byte. The optarg now points to
* just the IP address, and cp points to the port.
*/
case 'd':
if ((dst_ip = libnet_name2addr4(l, optarg, LIBNET_RESOLVE)) == -1)
{
fprintf(stderr, "Bad destination IP address: %s\n", optarg);
exit(EXIT_FAILURE);
}
break;
case 's':
if ((src_ip = libnet_name2addr4(l, optarg, LIBNET_RESOLVE)) == -1)
{
fprintf(stderr, "Bad source IP address: %s\n", optarg);
exit(EXIT_FAILURE);
}
break;
case 'p':
payload = (u_char *)optarg;
payload_s = strlen((char *)payload);
break;
case 'w':
withdraw_rt = (u_char *)optarg;
break;
case 'W':
u_rt_l = atoi(optarg);
break;
case 'a':
attr = (u_char *)optarg;
break;
case 'A':
attr_l = atoi(optarg);
break;
case 'i':
info = (u_char *)optarg;
break;
case 'I':
info_l = atoi(optarg);
break;
default:
exit(EXIT_FAILURE);
}
}
if (!src_ip || !dst_ip)
{
usage(argv[0]);
goto bad;
}
set_ptr_and_size(withdraw_rt, u_rt_l, 0x41, flag_w);
set_ptr_and_size(attr, attr_l, 0x42, flag_a);
set_ptr_and_size(info, info_l, 0x43, flag_i);
/*
* BGP4 update messages are "dynamic" are fields have variable size. The only
* sizes we know are those for the 2 first fields ... so we need to count them
* plus their value.
*/
length = LIBNET_BGP4_UPDATE_H + u_rt_l + attr_l + info_l + payload_s;
t = libnet_build_bgp4_update(
u_rt_l, /* Unfeasible Routes Length */
withdraw_rt, /* Withdrawn Routes */
attr_l, /* Total Path Attribute Length */
attr, /* Path Attributes */
info_l, /* Network Layer Reachability Information length */
info, /* Network Layer Reachability Information */
payload, /* payload */
payload_s, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (t == -1)
{
fprintf(stderr, "Can't build BGP4 update header: %s\n", libnet_geterror(l));
goto bad;
}
length+=LIBNET_BGP4_HEADER_H;
t = libnet_build_bgp4_header(
marker, /* marker */
length, /* length */
LIBNET_BGP4_UPDATE, /* message type */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (t == -1)
{
fprintf(stderr, "Can't build BGP4 header: %s\n", libnet_geterror(l));
goto bad;
}
length+=LIBNET_TCP_H;
t = libnet_build_tcp(
0x6666, /* source port */
179, /* destination port */
0x01010101, /* sequence number */
0x02020202, /* acknowledgement num */
TH_SYN, /* control flags */
32767, /* window size */
0, /* checksum */
0, /* urgent pointer */
length, /* TCP packet size */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (t == -1)
{
fprintf(stderr, "Can't build TCP header: %s\n", libnet_geterror(l));
goto bad;
}
length+=LIBNET_IPV4_H;
t = libnet_build_ipv4(
length, /* length */
0, /* TOS */
242, /* IP ID */
0, /* IP Frag */
64, /* TTL */
IPPROTO_TCP, /* protocol */
0, /* checksum */
src_ip, /* source IP */
dst_ip, /* destination IP */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (t == -1)
{
fprintf(stderr, "Can't build IP header: %s\n", libnet_geterror(l));
goto bad;
}
/*
* Write it to the wire.
*/
c = libnet_write(l);
if (c == -1)
{
fprintf(stderr, "Write error: %s\n", libnet_geterror(l));
goto bad;
}
else
{
fprintf(stderr, "Wrote %d byte TCP packet; check the wire.\n", c);
}
if (flag_w) free(withdraw_rt);
if (flag_a) free(attr);
if (flag_i) free(info);
libnet_destroy(l);
return (EXIT_SUCCESS);
bad:
if (flag_w) free(withdraw_rt);
if (flag_a) free(attr);
if (flag_i) free(info);
libnet_destroy(l);
return (EXIT_FAILURE);
}
void
usage(char *name)
{
fprintf(stderr,
"usage: %s -s source_ip -d destination_ip \n"
" [-m marker] [-p payload] [-S payload size]\n"
" [-w Withdrawn Routes] [-W Unfeasible Routes Length]\n"
" [-a Path Attributes] [-A Attribute Length]\n"
" [-i Reachability Information] [-I Reachability Information length]\n",
name);
}
/* EOF */
|
