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 #ifndef lint
23 static const char copyright[] _U_ =
24 "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
25 The Regents of the University of California. All rights reserved.\n";
26 #endif
27
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <stdarg.h>
32 #include <limits.h>
33 #ifdef _WIN32
34 #include "getopt.h"
35 #else
36 #include <unistd.h>
37 #endif
38 #include <errno.h>
39 #include <sys/types.h>
40
41 #include <pcap.h>
42
43 static char *program_name;
44
45 /*
46 * This was introduced by Clang:
47 *
48 * http://clang.llvm.org/docs/LanguageExtensions.html#has-attribute
49 *
50 * in some version (which version?); it has been picked up by GCC 5.0.
51 */
52 #ifndef __has_attribute
53 /*
54 * It's a macro, so you can check whether it's defined to check
55 * whether it's supported.
56 *
57 * If it's not, define it to always return 0, so that we move on to
58 * the fallback checks.
59 */
60 #define __has_attribute(x) 0
61 #endif
62
63 #if __has_attribute(noreturn) \
64 || (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 205)) \
65 || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590)) \
66 || (defined(__xlC__) && __xlC__ >= 0x0A01) \
67 || (defined(__HP_aCC) && __HP_aCC >= 61000)
68 /*
69 * Compiler with support for it, or GCC 2.5 and later, or Solaris Studio 12
70 * (Sun C 5.9) and later, or IBM XL C 10.1 and later (do any earlier
71 * versions of XL C support this?), or HP aCC A.06.10 and later.
72 */
73 #define PCAP_NORETURN __attribute((noreturn))
74 #elif defined( _MSC_VER )
75 #define PCAP_NORETURN __declspec(noreturn)
76 #else
77 #define PCAP_NORETURN
78 #endif
79
80 #if __has_attribute(__format__) \
81 || (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 203)) \
82 || (defined(__xlC__) && __xlC__ >= 0x0A01) \
83 || (defined(__HP_aCC) && __HP_aCC >= 61000)
84 /*
85 * Compiler with support for it, or GCC 2.3 and later, or IBM XL C 10.1
86 * and later (do any earlier versions of XL C support this?),
87 * or HP aCC A.06.10 and later.
88 */
89 #define PCAP_PRINTFLIKE(x,y) __attribute__((__format__(__printf__,x,y)))
90 #else
91 #define PCAP_PRINTFLIKE(x,y)
92 #endif
93
94 /* Forwards */
95 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
96 static void PCAP_NORETURN usage(void);
97 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
98 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
99 static char *copy_argv(char **);
100
101 static pcap_t *pd;
102
103 int
main(int argc,char ** argv)104 main(int argc, char **argv)
105 {
106 register int op;
107 register char *cp, *cmdbuf, *device;
108 long longarg;
109 char *p;
110 int timeout = 1000;
111 int immediate = 0;
112 int nonblock = 0;
113 bpf_u_int32 localnet, netmask;
114 struct bpf_program fcode;
115 char ebuf[PCAP_ERRBUF_SIZE];
116 int status;
117 int packet_count;
118
119 device = NULL;
120 if ((cp = strrchr(argv[0], '/')) != NULL)
121 program_name = cp + 1;
122 else
123 program_name = argv[0];
124
125 opterr = 0;
126 while ((op = getopt(argc, argv, "i:mnt:")) != -1) {
127 switch (op) {
128
129 case 'i':
130 device = optarg;
131 break;
132
133 case 'm':
134 immediate = 1;
135 break;
136
137 case 'n':
138 nonblock = 1;
139 break;
140
141 case 't':
142 longarg = strtol(optarg, &p, 10);
143 if (p == optarg || *p != '\0') {
144 error("Timeout value \"%s\" is not a number",
145 optarg);
146 /* NOTREACHED */
147 }
148 if (longarg < 0) {
149 error("Timeout value %ld is negative", longarg);
150 /* NOTREACHED */
151 }
152 if (longarg > INT_MAX) {
153 error("Timeout value %ld is too large (> %d)",
154 longarg, INT_MAX);
155 /* NOTREACHED */
156 }
157 timeout = (int)longarg;
158 break;
159
160 default:
161 usage();
162 /* NOTREACHED */
163 }
164 }
165
166 if (device == NULL) {
167 device = pcap_lookupdev(ebuf);
168 if (device == NULL)
169 error("%s", ebuf);
170 }
171 *ebuf = '\0';
172 pd = pcap_create(device, ebuf);
173 if (pd == NULL)
174 error("%s", ebuf);
175 status = pcap_set_snaplen(pd, 65535);
176 if (status != 0)
177 error("%s: pcap_set_snaplen failed: %s",
178 device, pcap_statustostr(status));
179 if (immediate) {
180 status = pcap_set_immediate_mode(pd, 1);
181 if (status != 0)
182 error("%s: pcap_set_immediate_mode failed: %s",
183 device, pcap_statustostr(status));
184 }
185 status = pcap_set_timeout(pd, timeout);
186 if (status != 0)
187 error("%s: pcap_set_timeout failed: %s",
188 device, pcap_statustostr(status));
189 status = pcap_activate(pd);
190 if (status < 0) {
191 /*
192 * pcap_activate() failed.
193 */
194 error("%s: %s\n(%s)", device,
195 pcap_statustostr(status), pcap_geterr(pd));
196 } else if (status > 0) {
197 /*
198 * pcap_activate() succeeded, but it's warning us
199 * of a problem it had.
200 */
201 warning("%s: %s\n(%s)", device,
202 pcap_statustostr(status), pcap_geterr(pd));
203 }
204 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
205 localnet = 0;
206 netmask = 0;
207 warning("%s", ebuf);
208 }
209 cmdbuf = copy_argv(&argv[optind]);
210
211 if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
212 error("%s", pcap_geterr(pd));
213
214 if (pcap_setfilter(pd, &fcode) < 0)
215 error("%s", pcap_geterr(pd));
216 if (pcap_setnonblock(pd, nonblock, ebuf) == -1)
217 error("pcap_setnonblock failed: %s", ebuf);
218 printf("Listening on %s\n", device);
219 for (;;) {
220 packet_count = 0;
221 status = pcap_dispatch(pd, -1, countme,
222 (u_char *)&packet_count);
223 if (status < 0)
224 break;
225 if (status != 0) {
226 printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
227 status, packet_count);
228 }
229 }
230 if (status == -2) {
231 /*
232 * We got interrupted, so perhaps we didn't
233 * manage to finish a line we were printing.
234 * Print an extra newline, just in case.
235 */
236 putchar('\n');
237 }
238 (void)fflush(stdout);
239 if (status == -1) {
240 /*
241 * Error. Report it.
242 */
243 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
244 program_name, pcap_geterr(pd));
245 }
246 pcap_close(pd);
247 exit(status == -1 ? 1 : 0);
248 }
249
250 static void
countme(u_char * user,const struct pcap_pkthdr * h,const u_char * sp)251 countme(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
252 {
253 int *counterp = (int *)user;
254
255 (*counterp)++;
256 }
257
258 static void
usage(void)259 usage(void)
260 {
261 (void)fprintf(stderr, "Usage: %s [ -mn ] [ -i interface ] [ -t timeout] [expression]\n",
262 program_name);
263 exit(1);
264 }
265
266 /* VARARGS */
267 static void
error(const char * fmt,...)268 error(const char *fmt, ...)
269 {
270 va_list ap;
271
272 (void)fprintf(stderr, "%s: ", program_name);
273 va_start(ap, fmt);
274 (void)vfprintf(stderr, fmt, ap);
275 va_end(ap);
276 if (*fmt) {
277 fmt += strlen(fmt);
278 if (fmt[-1] != '\n')
279 (void)fputc('\n', stderr);
280 }
281 exit(1);
282 /* NOTREACHED */
283 }
284
285 /* VARARGS */
286 static void
warning(const char * fmt,...)287 warning(const char *fmt, ...)
288 {
289 va_list ap;
290
291 (void)fprintf(stderr, "%s: WARNING: ", program_name);
292 va_start(ap, fmt);
293 (void)vfprintf(stderr, fmt, ap);
294 va_end(ap);
295 if (*fmt) {
296 fmt += strlen(fmt);
297 if (fmt[-1] != '\n')
298 (void)fputc('\n', stderr);
299 }
300 }
301
302 /*
303 * Copy arg vector into a new buffer, concatenating arguments with spaces.
304 */
305 static char *
copy_argv(register char ** argv)306 copy_argv(register char **argv)
307 {
308 register char **p;
309 register u_int len = 0;
310 char *buf;
311 char *src, *dst;
312
313 p = argv;
314 if (*p == 0)
315 return 0;
316
317 while (*p)
318 len += strlen(*p++) + 1;
319
320 buf = (char *)malloc(len);
321 if (buf == NULL)
322 error("copy_argv: malloc");
323
324 p = argv;
325 dst = buf;
326 while ((src = *p++) != NULL) {
327 while ((*dst++ = *src++) != '\0')
328 ;
329 dst[-1] = ' ';
330 }
331 dst[-1] = '\0';
332
333 return buf;
334 }
335