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 static const char rcsid[] _U_ =
27     "@(#) $Header: /tcpdump/master/libpcap/filtertest.c,v 1.2 2005-08-08 17:50:13 guy Exp $ (LBL)";
28 #endif
29 
30 #ifdef HAVE_CONFIG_H
31 #include "config.h"
32 #endif
33 
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <stdarg.h>
38 #include <unistd.h>
39 #include <fcntl.h>
40 #include <errno.h>
41 #include <arpa/inet.h>
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 
45 #if defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
46 /* BSD-flavored OS - use BPF */
47 #define USE_BPF
48 #elif defined(linux)
49 /* Linux - use socket filters */
50 #define USE_SOCKET_FILTERS
51 #else
52 #error "Unknown platform or platform that doesn't support Valgrind"
53 #endif
54 
55 #if defined(USE_BPF)
56 
57 #include <sys/ioctl.h>
58 #include <net/bpf.h>
59 
60 /*
61  * Make "pcap.h" not include "pcap/bpf.h"; we are going to include the
62  * native OS version, as we're going to be doing our own ioctls to
63  * make sure that, in the uninitialized-data tests, the filters aren't
64  * checked by libpcap before being handed to BPF.
65  */
66 #define PCAP_DONT_INCLUDE_PCAP_BPF_H
67 
68 #elif defined(USE_SOCKET_FILTERS)
69 
70 #include <sys/socket.h>
71 #include <linux/types.h>
72 #include <linux/filter.h>
73 
74 #endif
75 
76 #include <pcap.h>
77 #ifndef HAVE___ATTRIBUTE__
78 #define __attribute__(x)
79 #endif
80 
81 static char *program_name;
82 
83 /* Forwards */
84 static void usage(void) __attribute__((noreturn));
85 static void error(const char *, ...)
86     __attribute__((noreturn, format (printf, 1, 2)));
87 static void warning(const char *, ...)
88     __attribute__((format (printf, 1, 2)));
89 
90 extern int optind;
91 extern int opterr;
92 extern char *optarg;
93 
94 /*
95  * On Windows, we need to open the file in binary mode, so that
96  * we get all the bytes specified by the size we get from "fstat()".
97  * On UNIX, that's not necessary.  O_BINARY is defined on Windows;
98  * we define it as 0 if it's not defined, so it does nothing.
99  */
100 #ifndef O_BINARY
101 #define O_BINARY	0
102 #endif
103 
104 static char *
read_infile(char * fname)105 read_infile(char *fname)
106 {
107 	register int i, fd, cc;
108 	register char *cp;
109 	struct stat buf;
110 
111 	fd = open(fname, O_RDONLY|O_BINARY);
112 	if (fd < 0)
113 		error("can't open %s: %s", fname, pcap_strerror(errno));
114 
115 	if (fstat(fd, &buf) < 0)
116 		error("can't stat %s: %s", fname, pcap_strerror(errno));
117 
118 	cp = malloc((u_int)buf.st_size + 1);
119 	if (cp == NULL)
120 		error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1,
121 			fname, pcap_strerror(errno));
122 	cc = read(fd, cp, (u_int)buf.st_size);
123 	if (cc < 0)
124 		error("read %s: %s", fname, pcap_strerror(errno));
125 	if (cc != buf.st_size)
126 		error("short read %s (%d != %d)", fname, cc, (int)buf.st_size);
127 
128 	close(fd);
129 	/* replace "# comment" with spaces */
130 	for (i = 0; i < cc; i++) {
131 		if (cp[i] == '#')
132 			while (i < cc && cp[i] != '\n')
133 				cp[i++] = ' ';
134 	}
135 	cp[cc] = '\0';
136 	return (cp);
137 }
138 
139 /* VARARGS */
140 static void
error(const char * fmt,...)141 error(const char *fmt, ...)
142 {
143 	va_list ap;
144 
145 	(void)fprintf(stderr, "%s: ", program_name);
146 	va_start(ap, fmt);
147 	(void)vfprintf(stderr, fmt, ap);
148 	va_end(ap);
149 	if (*fmt) {
150 		fmt += strlen(fmt);
151 		if (fmt[-1] != '\n')
152 			(void)fputc('\n', stderr);
153 	}
154 	exit(1);
155 	/* NOTREACHED */
156 }
157 
158 /* VARARGS */
159 static void
warning(const char * fmt,...)160 warning(const char *fmt, ...)
161 {
162 	va_list ap;
163 
164 	(void)fprintf(stderr, "%s: WARNING: ", program_name);
165 	va_start(ap, fmt);
166 	(void)vfprintf(stderr, fmt, ap);
167 	va_end(ap);
168 	if (*fmt) {
169 		fmt += strlen(fmt);
170 		if (fmt[-1] != '\n')
171 			(void)fputc('\n', stderr);
172 	}
173 }
174 
175 /*
176  * Copy arg vector into a new buffer, concatenating arguments with spaces.
177  */
178 static char *
copy_argv(register char ** argv)179 copy_argv(register char **argv)
180 {
181 	register char **p;
182 	register u_int len = 0;
183 	char *buf;
184 	char *src, *dst;
185 
186 	p = argv;
187 	if (*p == 0)
188 		return 0;
189 
190 	while (*p)
191 		len += strlen(*p++) + 1;
192 
193 	buf = (char *)malloc(len);
194 	if (buf == NULL)
195 		error("copy_argv: malloc");
196 
197 	p = argv;
198 	dst = buf;
199 	while ((src = *p++) != NULL) {
200 		while ((*dst++ = *src++) != '\0')
201 			;
202 		dst[-1] = ' ';
203 	}
204 	dst[-1] = '\0';
205 
206 	return buf;
207 }
208 
209 #define INSN_COUNT	17
210 
211 int
main(int argc,char ** argv)212 main(int argc, char **argv)
213 {
214 	char *cp, *device;
215 	int op;
216 	int dorfmon, useactivate;
217 	char ebuf[PCAP_ERRBUF_SIZE];
218 	char *infile;
219 	char *cmdbuf;
220 	pcap_t *pd;
221 	int status = 0;
222 	int pcap_fd;
223 #if defined(USE_BPF)
224 	struct bpf_program bad_fcode;
225 	struct bpf_insn uninitialized[INSN_COUNT];
226 #elif defined(USE_SOCKET_FILTERS)
227 	struct sock_fprog bad_fcode;
228 	struct sock_filter uninitialized[INSN_COUNT];
229 #endif
230 	struct bpf_program fcode;
231 
232 	device = NULL;
233 	dorfmon = 0;
234 	useactivate = 0;
235 	infile = NULL;
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, "aF:i:I")) != -1) {
244 		switch (op) {
245 
246 		case 'a':
247 			useactivate = 1;
248 			break;
249 
250 		case 'F':
251 			infile = optarg;
252 			break;
253 
254 		case 'i':
255 			device = optarg;
256 			break;
257 
258 		case 'I':
259 			dorfmon = 1;
260 			useactivate = 1;	/* required for rfmon */
261 			break;
262 
263 		default:
264 			usage();
265 			/* NOTREACHED */
266 		}
267 	}
268 
269 	if (device == NULL) {
270 		/*
271 		 * No interface specified; get whatever pcap_lookupdev()
272 		 * finds.
273 		 */
274 		device = pcap_lookupdev(ebuf);
275 		if (device == NULL) {
276 			error("couldn't find interface to use: %s",
277 			    ebuf);
278 		}
279 	}
280 
281 	if (infile != NULL) {
282 		/*
283 		 * Filter specified with "-F" and a file containing
284 		 * a filter.
285 		 */
286 		cmdbuf = read_infile(infile);
287 	} else {
288 		if (optind < argc) {
289 			/*
290 			 * Filter specified with arguments on the
291 			 * command line.
292 			 */
293 			cmdbuf = copy_argv(&argv[optind+1]);
294 		} else {
295 			/*
296 			 * No filter specified; use an empty string, which
297 			 * compiles to an "accept all" filter.
298 			 */
299 			cmdbuf = "";
300 		}
301 	}
302 
303 	if (useactivate) {
304 		pd = pcap_create(device, ebuf);
305 		if (pd == NULL)
306 			error("%s: pcap_create() failed: %s", device, ebuf);
307 		status = pcap_set_snaplen(pd, 65535);
308 		if (status != 0)
309 			error("%s: pcap_set_snaplen failed: %s",
310 			    device, pcap_statustostr(status));
311 		status = pcap_set_promisc(pd, 1);
312 		if (status != 0)
313 			error("%s: pcap_set_promisc failed: %s",
314 			    device, pcap_statustostr(status));
315 		if (dorfmon) {
316 			status = pcap_set_rfmon(pd, 1);
317 			if (status != 0)
318 				error("%s: pcap_set_rfmon failed: %s",
319 				    device, pcap_statustostr(status));
320 		}
321 		status = pcap_set_timeout(pd, 1000);
322 		if (status != 0)
323 			error("%s: pcap_set_timeout failed: %s",
324 			    device, pcap_statustostr(status));
325 		status = pcap_activate(pd);
326 		if (status < 0) {
327 			/*
328 			 * pcap_activate() failed.
329 			 */
330 			error("%s: %s\n(%s)", device,
331 			    pcap_statustostr(status), pcap_geterr(pd));
332 		} else if (status > 0) {
333 			/*
334 			 * pcap_activate() succeeded, but it's warning us
335 			 * of a problem it had.
336 			 */
337 			warning("%s: %s\n(%s)", device,
338 			    pcap_statustostr(status), pcap_geterr(pd));
339 		}
340 	} else {
341 		*ebuf = '\0';
342 		pd = pcap_open_live(device, 65535, 1, 1000, ebuf);
343 		if (pd == NULL)
344 			error("%s", ebuf);
345 		else if (*ebuf)
346 			warning("%s", ebuf);
347 	}
348 
349 	pcap_fd = pcap_fileno(pd);
350 
351 	/*
352 	 * Try setting a filter with an uninitialized bpf_program
353 	 * structure.  This should cause valgrind to report a
354 	 * problem.
355 	 *
356 	 * We don't check for errors, because it could get an
357 	 * error due to a bad pointer or count.
358 	 */
359 #if defined(USE_BPF)
360 	ioctl(pcap_fd, BIOCSETF, &bad_fcode);
361 #elif defined(USE_SOCKET_FILTERS)
362 	setsockopt(pcap_fd, SOL_SOCKET, SO_ATTACH_FILTER, &bad_fcode,
363 	    sizeof(bad_fcode));
364 #endif
365 
366 	/*
367 	 * Try setting a filter with an initialized bpf_program
368 	 * structure that points to an uninitialized program.
369 	 * That should also cause valgrind to report a problem.
370 	 *
371 	 * We don't check for errors, because it could get an
372 	 * error due to a bad pointer or count.
373 	 */
374 #if defined(USE_BPF)
375 	bad_fcode.bf_len = INSN_COUNT;
376 	bad_fcode.bf_insns = uninitialized;
377 	ioctl(pcap_fd, BIOCSETF, &bad_fcode);
378 #elif defined(USE_SOCKET_FILTERS)
379 	bad_fcode.len = INSN_COUNT;
380 	bad_fcode.filter = uninitialized;
381 	setsockopt(pcap_fd, SOL_SOCKET, SO_ATTACH_FILTER, &bad_fcode,
382 	    sizeof(bad_fcode));
383 #endif
384 
385 	/*
386 	 * Now compile a filter and set the filter with that.
387 	 * That should *not* cause valgrind to report a
388 	 * problem.
389 	 */
390 	if (pcap_compile(pd, &fcode, cmdbuf, 1, 0) < 0)
391 		error("can't compile filter: %s", pcap_geterr(pd));
392 	if (pcap_setfilter(pd, &fcode) < 0)
393 		error("can't set filter: %s", pcap_geterr(pd));
394 
395 	pcap_close(pd);
396 	exit(status < 0 ? 1 : 0);
397 }
398 
399 static void
usage(void)400 usage(void)
401 {
402 	(void)fprintf(stderr, "%s, with %s\n", program_name,
403 	    pcap_lib_version());
404 	(void)fprintf(stderr,
405 	    "Usage: %s [-aI] [ -F file ] [ -I interface ] [ expression ]\n",
406 	    program_name);
407 	exit(1);
408 }
409