1 /*
2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 */
21
22 #include "varattrs.h"
23
24 #ifndef lint
25 static const char copyright[] _U_ =
26 "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
27 The Regents of the University of California. All rights reserved.\n";
28 #endif
29
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <stdarg.h>
34 #include <limits.h>
35 #ifdef _WIN32
36 #include "getopt.h"
37 #else
38 #include <unistd.h>
39 #endif
40 #include <errno.h>
41 #ifndef _WIN32
42 #include <signal.h>
43 #endif
44 #include <sys/types.h>
45
46 #include <pcap.h>
47
48 #include "pcap/funcattrs.h"
49
50 #ifdef _WIN32
51 #include "portability.h"
52 #endif
53
54 static char *program_name;
55
56 /* Forwards */
57 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
58 static void PCAP_NORETURN usage(void);
59 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
60 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
61 static char *copy_argv(char **);
62
63 static pcap_t *pd;
64 #ifndef _WIN32
65 static int breaksigint = 0;
66 #endif
67
68 #ifndef _WIN32
69 static void
sigint_handler(int signum _U_)70 sigint_handler(int signum _U_)
71 {
72 if (breaksigint)
73 pcap_breakloop(pd);
74 }
75 #endif
76
77 #ifdef _WIN32
78 /*
79 * We don't have UN*X-style signals, so we don't have anything to test.
80 */
81 #define B_OPTION ""
82 #define R_OPTION ""
83 #define S_OPTION ""
84 #else
85 /*
86 * We do have UN*X-style signals (we assume that "not Windows" means "UN*X").
87 */
88 #define B_OPTION "b"
89 #define R_OPTION "r"
90 #define S_OPTION "s"
91 #endif
92
93 #define COMMAND_OPTIONS B_OPTION "i:mn" R_OPTION S_OPTION "t:"
94 #define USAGE_OPTIONS "-" B_OPTION "mn" R_OPTION S_OPTION
95
96 int
main(int argc,char ** argv)97 main(int argc, char **argv)
98 {
99 register int op;
100 register char *cp, *cmdbuf, *device;
101 long longarg;
102 char *p;
103 int timeout = 1000;
104 int immediate = 0;
105 int nonblock = 0;
106 #ifndef _WIN32
107 int sigrestart = 0;
108 int catchsigint = 0;
109 #endif
110 pcap_if_t *devlist;
111 bpf_u_int32 localnet, netmask;
112 struct bpf_program fcode;
113 char ebuf[PCAP_ERRBUF_SIZE];
114 int status;
115 int packet_count;
116
117 device = NULL;
118 if ((cp = strrchr(argv[0], '/')) != NULL)
119 program_name = cp + 1;
120 else
121 program_name = argv[0];
122
123 opterr = 0;
124 while ((op = getopt(argc, argv, COMMAND_OPTIONS)) != -1) {
125 switch (op) {
126
127 #ifndef _WIN32
128 case 'b':
129 breaksigint = 1;
130 break;
131 #endif
132
133 case 'i':
134 device = optarg;
135 break;
136
137 case 'm':
138 immediate = 1;
139 break;
140
141 case 'n':
142 nonblock = 1;
143 break;
144
145 #ifndef _WIN32
146 case 'r':
147 sigrestart = 1;
148 break;
149
150 case 's':
151 catchsigint = 1;
152 break;
153 #endif
154
155 case 't':
156 longarg = strtol(optarg, &p, 10);
157 if (p == optarg || *p != '\0') {
158 error("Timeout value \"%s\" is not a number",
159 optarg);
160 /* NOTREACHED */
161 }
162 if (longarg < 0) {
163 error("Timeout value %ld is negative", longarg);
164 /* NOTREACHED */
165 }
166 if (longarg > INT_MAX) {
167 error("Timeout value %ld is too large (> %d)",
168 longarg, INT_MAX);
169 /* NOTREACHED */
170 }
171 timeout = (int)longarg;
172 break;
173
174 default:
175 usage();
176 /* NOTREACHED */
177 }
178 }
179
180 if (device == NULL) {
181 if (pcap_findalldevs(&devlist, ebuf) == -1)
182 error("%s", ebuf);
183 if (devlist == NULL)
184 error("no interfaces available for capture");
185 device = strdup(devlist->name);
186 pcap_freealldevs(devlist);
187 }
188 *ebuf = '\0';
189
190 #ifndef _WIN32
191 /*
192 * If we were told to catch SIGINT, do so.
193 */
194 if (catchsigint) {
195 struct sigaction action;
196
197 action.sa_handler = sigint_handler;
198 sigemptyset(&action.sa_mask);
199
200 /*
201 * Should SIGINT interrupt, or restart, system calls?
202 */
203 action.sa_flags = sigrestart ? SA_RESTART : 0;
204
205 if (sigaction(SIGINT, &action, NULL) == -1)
206 error("Can't catch SIGINT: %s\n",
207 strerror(errno));
208 }
209 #endif
210
211 pd = pcap_create(device, ebuf);
212 if (pd == NULL)
213 error("%s", ebuf);
214 status = pcap_set_snaplen(pd, 65535);
215 if (status != 0)
216 error("%s: pcap_set_snaplen failed: %s",
217 device, pcap_statustostr(status));
218 if (immediate) {
219 status = pcap_set_immediate_mode(pd, 1);
220 if (status != 0)
221 error("%s: pcap_set_immediate_mode failed: %s",
222 device, pcap_statustostr(status));
223 }
224 status = pcap_set_timeout(pd, timeout);
225 if (status != 0)
226 error("%s: pcap_set_timeout failed: %s",
227 device, pcap_statustostr(status));
228 status = pcap_activate(pd);
229 if (status < 0) {
230 /*
231 * pcap_activate() failed.
232 */
233 error("%s: %s\n(%s)", device,
234 pcap_statustostr(status), pcap_geterr(pd));
235 } else if (status > 0) {
236 /*
237 * pcap_activate() succeeded, but it's warning us
238 * of a problem it had.
239 */
240 warning("%s: %s\n(%s)", device,
241 pcap_statustostr(status), pcap_geterr(pd));
242 }
243 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
244 localnet = 0;
245 netmask = 0;
246 warning("%s", ebuf);
247 }
248 cmdbuf = copy_argv(&argv[optind]);
249
250 if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
251 error("%s", pcap_geterr(pd));
252
253 if (pcap_setfilter(pd, &fcode) < 0)
254 error("%s", pcap_geterr(pd));
255 if (pcap_setnonblock(pd, nonblock, ebuf) == -1)
256 error("pcap_setnonblock failed: %s", ebuf);
257 printf("Listening on %s\n", device);
258 for (;;) {
259 packet_count = 0;
260 status = pcap_dispatch(pd, -1, countme,
261 (u_char *)&packet_count);
262 if (status < 0)
263 break;
264 if (status != 0) {
265 printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
266 status, packet_count);
267 struct pcap_stat ps;
268 pcap_stats(pd, &ps);
269 printf("%d ps_recv, %d ps_drop, %d ps_ifdrop\n",
270 ps.ps_recv, ps.ps_drop, ps.ps_ifdrop);
271 }
272 }
273 if (status == -2) {
274 /*
275 * We got interrupted, so perhaps we didn't
276 * manage to finish a line we were printing.
277 * Print an extra newline, just in case.
278 */
279 putchar('\n');
280 printf("Broken out of loop from SIGINT handler\n");
281 }
282 (void)fflush(stdout);
283 if (status == -1) {
284 /*
285 * Error. Report it.
286 */
287 (void)fprintf(stderr, "%s: pcap_dispatch: %s\n",
288 program_name, pcap_geterr(pd));
289 }
290 pcap_close(pd);
291 pcap_freecode(&fcode);
292 free(cmdbuf);
293 exit(status == -1 ? 1 : 0);
294 }
295
296 static void
countme(u_char * user,const struct pcap_pkthdr * h _U_,const u_char * sp _U_)297 countme(u_char *user, const struct pcap_pkthdr *h _U_, const u_char *sp _U_)
298 {
299 int *counterp = (int *)user;
300
301 (*counterp)++;
302 }
303
304 static void
usage(void)305 usage(void)
306 {
307 (void)fprintf(stderr, "Usage: %s [ " USAGE_OPTIONS " ] [ -i interface ] [ -t timeout] [expression]\n",
308 program_name);
309 exit(1);
310 }
311
312 /* VARARGS */
313 static void
error(const char * fmt,...)314 error(const char *fmt, ...)
315 {
316 va_list ap;
317
318 (void)fprintf(stderr, "%s: ", program_name);
319 va_start(ap, fmt);
320 (void)vfprintf(stderr, fmt, ap);
321 va_end(ap);
322 if (*fmt) {
323 fmt += strlen(fmt);
324 if (fmt[-1] != '\n')
325 (void)fputc('\n', stderr);
326 }
327 exit(1);
328 /* NOTREACHED */
329 }
330
331 /* VARARGS */
332 static void
warning(const char * fmt,...)333 warning(const char *fmt, ...)
334 {
335 va_list ap;
336
337 (void)fprintf(stderr, "%s: WARNING: ", program_name);
338 va_start(ap, fmt);
339 (void)vfprintf(stderr, fmt, ap);
340 va_end(ap);
341 if (*fmt) {
342 fmt += strlen(fmt);
343 if (fmt[-1] != '\n')
344 (void)fputc('\n', stderr);
345 }
346 }
347
348 /*
349 * Copy arg vector into a new buffer, concatenating arguments with spaces.
350 */
351 static char *
copy_argv(register char ** argv)352 copy_argv(register char **argv)
353 {
354 register char **p;
355 register size_t len = 0;
356 char *buf;
357 char *src, *dst;
358
359 p = argv;
360 if (*p == 0)
361 return 0;
362
363 while (*p)
364 len += strlen(*p++) + 1;
365
366 buf = (char *)malloc(len);
367 if (buf == NULL)
368 error("copy_argv: malloc");
369
370 p = argv;
371 dst = buf;
372 while ((src = *p++) != NULL) {
373 while ((*dst++ = *src++) != '\0')
374 ;
375 dst[-1] = ' ';
376 }
377 dst[-1] = '\0';
378
379 return buf;
380 }
381