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 <config.h>
31
32 #include <pcap.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <stdarg.h>
37 #include <limits.h>
38 #ifdef _WIN32
39 #include "getopt.h"
40 #include "unix.h"
41 #else
42 #include <unistd.h>
43 #endif
44 #include <fcntl.h>
45 #include <errno.h>
46 #ifdef _WIN32
47 #include <winsock2.h>
48 #include <ws2tcpip.h>
49 #else
50 #include <sys/socket.h>
51 #include <arpa/inet.h>
52 #endif
53 #include <sys/types.h>
54 #include <sys/stat.h>
55
56 #include "pcap/funcattrs.h"
57
58 #define MAXIMUM_SNAPLEN 262144
59
60 #ifdef BDEBUG
61 /*
62 * We have pcap_set_optimizer_debug() and pcap_set_print_dot_graph() in
63 * libpcap; declare them (they're not declared by any libpcap header,
64 * because they're special hacks, only available if libpcap was configured
65 * to include them, and only intended for use by libpcap developers trying
66 * to debug the optimizer for filter expressions).
67 */
68 PCAP_API void pcap_set_optimizer_debug(int);
69 PCAP_API void pcap_set_print_dot_graph(int);
70 #endif
71
72 static char *program_name;
73
74 /* Forwards */
75 static void PCAP_NORETURN usage(void);
76 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
77 static void warn(const char *, ...) PCAP_PRINTFLIKE(1, 2);
78
79 /*
80 * On Windows, we need to open the file in binary mode, so that
81 * we get all the bytes specified by the size we get from "fstat()".
82 * On UNIX, that's not necessary. O_BINARY is defined on Windows;
83 * we define it as 0 if it's not defined, so it does nothing.
84 */
85 #ifndef O_BINARY
86 #define O_BINARY 0
87 #endif
88
89 static char *
read_infile(char * fname)90 read_infile(char *fname)
91 {
92 register int i, fd, cc;
93 register char *cp;
94 struct stat buf;
95
96 fd = open(fname, O_RDONLY|O_BINARY);
97 if (fd < 0)
98 error("can't open %s: %s", fname, pcap_strerror(errno));
99
100 if (fstat(fd, &buf) < 0)
101 error("can't stat %s: %s", fname, pcap_strerror(errno));
102
103 /*
104 * _read(), on Windows, has an unsigned int byte count and an
105 * int return value, so we can't handle a file bigger than
106 * INT_MAX - 1 bytes (and have no reason to do so; a filter *that*
107 * big will take forever to compile). (The -1 is for the '\0' at
108 * the end of the string.)
109 */
110 if (buf.st_size > INT_MAX - 1)
111 error("%s is larger than %d bytes; that's too large", fname,
112 INT_MAX - 1);
113 cp = malloc((u_int)buf.st_size + 1);
114 if (cp == NULL)
115 error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1,
116 fname, pcap_strerror(errno));
117 cc = (int)read(fd, cp, (u_int)buf.st_size);
118 if (cc < 0)
119 error("read %s: %s", fname, pcap_strerror(errno));
120 if (cc != buf.st_size)
121 error("short read %s (%d != %d)", fname, cc, (int)buf.st_size);
122
123 close(fd);
124 /* replace "# comment" with spaces */
125 for (i = 0; i < cc; i++) {
126 if (cp[i] == '#')
127 while (i < cc && cp[i] != '\n')
128 cp[i++] = ' ';
129 }
130 cp[cc] = '\0';
131 return (cp);
132 }
133
134 /* VARARGS */
135 static void
error(const char * fmt,...)136 error(const char *fmt, ...)
137 {
138 va_list ap;
139
140 (void)fprintf(stderr, "%s: ", program_name);
141 va_start(ap, fmt);
142 (void)vfprintf(stderr, fmt, ap);
143 va_end(ap);
144 if (*fmt) {
145 fmt += strlen(fmt);
146 if (fmt[-1] != '\n')
147 (void)fputc('\n', stderr);
148 }
149 exit(1);
150 /* NOTREACHED */
151 }
152
153 /* VARARGS */
154 static void
warn(const char * fmt,...)155 warn(const char *fmt, ...)
156 {
157 va_list ap;
158
159 (void)fprintf(stderr, "%s: WARNING: ", program_name);
160 va_start(ap, fmt);
161 (void)vfprintf(stderr, fmt, ap);
162 va_end(ap);
163 if (*fmt) {
164 fmt += strlen(fmt);
165 if (fmt[-1] != '\n')
166 (void)fputc('\n', stderr);
167 }
168 }
169
170 /*
171 * Copy arg vector into a new buffer, concatenating arguments with spaces.
172 */
173 static char *
copy_argv(register char ** argv)174 copy_argv(register char **argv)
175 {
176 register char **p;
177 register size_t len = 0;
178 char *buf;
179 char *src, *dst;
180
181 p = argv;
182 if (*p == 0)
183 return 0;
184
185 while (*p)
186 len += strlen(*p++) + 1;
187
188 buf = (char *)malloc(len);
189 if (buf == NULL)
190 error("copy_argv: malloc");
191
192 p = argv;
193 dst = buf;
194 while ((src = *p++) != NULL) {
195 while ((*dst++ = *src++) != '\0')
196 ;
197 dst[-1] = ' ';
198 }
199 dst[-1] = '\0';
200
201 return buf;
202 }
203
204 int
main(int argc,char ** argv)205 main(int argc, char **argv)
206 {
207 char *cp;
208 int op;
209 int dflag;
210 #ifdef BDEBUG
211 int gflag;
212 #endif
213 char *infile;
214 int Oflag;
215 int snaplen;
216 char *p;
217 int dlt;
218 bpf_u_int32 netmask = PCAP_NETMASK_UNKNOWN;
219 char *cmdbuf;
220 pcap_t *pd;
221 struct bpf_program fcode;
222
223 #ifdef _WIN32
224 if (pcap_wsockinit() != 0)
225 return 1;
226 #endif /* _WIN32 */
227
228 dflag = 1;
229 #ifdef BDEBUG
230 gflag = 0;
231 #endif
232
233 infile = NULL;
234 Oflag = 1;
235 snaplen = MAXIMUM_SNAPLEN;
236
237 if ((cp = strrchr(argv[0], '/')) != NULL)
238 program_name = cp + 1;
239 else
240 program_name = argv[0];
241
242 opterr = 0;
243 while ((op = getopt(argc, argv, "dF:gm:Os:")) != -1) {
244 switch (op) {
245
246 case 'd':
247 ++dflag;
248 break;
249
250 case 'g':
251 #ifdef BDEBUG
252 ++gflag;
253 break;
254 #else
255 error("libpcap and filtertest not built with optimizer debugging enabled");
256 #endif
257
258 case 'F':
259 infile = optarg;
260 break;
261
262 case 'O':
263 Oflag = 0;
264 break;
265
266 case 'm': {
267 bpf_u_int32 addr;
268
269 switch (inet_pton(AF_INET, optarg, &addr)) {
270
271 case 0:
272 error("invalid netmask %s", optarg);
273
274 case -1:
275 error("invalid netmask %s: %s", optarg,
276 pcap_strerror(errno));
277
278 case 1:
279 netmask = addr;
280 break;
281 }
282 break;
283 }
284
285 case 's': {
286 char *end;
287 long long_snaplen;
288
289 long_snaplen = strtol(optarg, &end, 0);
290 if (optarg == end || *end != '\0'
291 || long_snaplen < 0
292 || long_snaplen > MAXIMUM_SNAPLEN)
293 error("invalid snaplen %s", optarg);
294 else {
295 if (snaplen == 0)
296 snaplen = MAXIMUM_SNAPLEN;
297 else
298 snaplen = (int)long_snaplen;
299 }
300 break;
301 }
302
303 default:
304 usage();
305 /* NOTREACHED */
306 }
307 }
308
309 if (optind >= argc) {
310 usage();
311 /* NOTREACHED */
312 }
313
314 dlt = pcap_datalink_name_to_val(argv[optind]);
315 if (dlt < 0) {
316 dlt = (int)strtol(argv[optind], &p, 10);
317 if (p == argv[optind] || *p != '\0')
318 error("invalid data link type %s", argv[optind]);
319 }
320
321 if (infile)
322 cmdbuf = read_infile(infile);
323 else
324 cmdbuf = copy_argv(&argv[optind+1]);
325
326 #ifdef BDEBUG
327 pcap_set_optimizer_debug(dflag);
328 pcap_set_print_dot_graph(gflag);
329 #endif
330
331 pd = pcap_open_dead(dlt, snaplen);
332 if (pd == NULL)
333 error("Can't open fake pcap_t");
334
335 if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
336 error("%s", pcap_geterr(pd));
337
338 if (!bpf_validate(fcode.bf_insns, fcode.bf_len))
339 warn("Filter doesn't pass validation");
340
341 #ifdef BDEBUG
342 if (cmdbuf != NULL) {
343 // replace line feed with space
344 for (cp = cmdbuf; *cp != '\0'; ++cp) {
345 if (*cp == '\r' || *cp == '\n') {
346 *cp = ' ';
347 }
348 }
349 // only show machine code if BDEBUG defined, since dflag > 3
350 printf("machine codes for filter: %s\n", cmdbuf);
351 } else
352 printf("machine codes for empty filter:\n");
353 #endif
354
355 bpf_dump(&fcode, dflag);
356 free(cmdbuf);
357 pcap_freecode (&fcode);
358 pcap_close(pd);
359 exit(0);
360 }
361
362 static void
usage(void)363 usage(void)
364 {
365 (void)fprintf(stderr, "%s, with %s\n", program_name,
366 pcap_lib_version());
367 (void)fprintf(stderr,
368 #ifdef BDEBUG
369 "Usage: %s [-dgO] [ -F file ] [ -m netmask] [ -s snaplen ] dlt [ expression ]\n",
370 #else
371 "Usage: %s [-dO] [ -F file ] [ -m netmask] [ -s snaplen ] dlt [ expression ]\n",
372 #endif
373 program_name);
374 exit(1);
375 }
376