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
25static const char copyright[] _U_ =
26    "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
27The 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 <winsock2.h>
37  #include <windows.h>
38
39  #define THREAD_HANDLE			HANDLE
40  #define THREAD_FUNC_ARG_TYPE		LPVOID
41  #define THREAD_FUNC_RETURN_TYPE	DWORD __stdcall
42
43  #include "getopt.h"
44#else
45  #include <pthread.h>
46  #include <signal.h>
47  #include <unistd.h>
48
49  #define THREAD_HANDLE			pthread_t
50  #define THREAD_FUNC_ARG_TYPE		void *
51  #define THREAD_FUNC_RETURN_TYPE	void *
52#endif
53#include <errno.h>
54#include <sys/types.h>
55
56#include <pcap.h>
57
58#include "pcap/funcattrs.h"
59
60#ifdef _WIN32
61  #include "portability.h"
62#endif
63
64static char *program_name;
65
66/* Forwards */
67static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
68static void PCAP_NORETURN usage(void);
69static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
70static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
71static char *copy_argv(char **);
72
73static pcap_t *pd;
74
75#ifdef _WIN32
76/*
77 * Generate a string for a Win32-specific error (i.e. an error generated when
78 * calling a Win32 API).
79 * For errors occurred during standard C calls, we still use pcap_strerror()
80 */
81#define ERRBUF_SIZE	1024
82static const char *
83win32_strerror(DWORD error)
84{
85  static char errbuf[ERRBUF_SIZE+1];
86  size_t errlen;
87
88  FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf,
89                ERRBUF_SIZE, NULL);
90
91  /*
92   * "FormatMessage()" "helpfully" sticks CR/LF at the end of the
93   * message.  Get rid of it.
94   */
95  errlen = strlen(errbuf);
96  if (errlen >= 2) {
97    errbuf[errlen - 1] = '\0';
98    errbuf[errlen - 2] = '\0';
99    errlen -= 2;
100  }
101  return errbuf;
102}
103#else
104static void
105catch_sigusr1(int sig _U_)
106{
107	printf("Got SIGUSR1\n");
108}
109#endif
110
111static void
112sleep_secs(int secs)
113{
114#ifdef _WIN32
115	Sleep(secs*1000);
116#else
117	unsigned secs_remaining;
118
119	if (secs <= 0)
120		return;
121	secs_remaining = secs;
122	while (secs_remaining != 0)
123		secs_remaining = sleep(secs_remaining);
124#endif
125}
126
127static THREAD_FUNC_RETURN_TYPE
128capture_thread_func(THREAD_FUNC_ARG_TYPE arg)
129{
130	char *device = arg;
131	int packet_count;
132	int status;
133#ifndef _WIN32
134	struct sigaction action;
135	sigset_t mask;
136#endif
137
138#ifndef _WIN32
139	sigemptyset(&mask);
140	action.sa_handler = catch_sigusr1;
141	action.sa_mask = mask;
142	action.sa_flags = 0;
143	if (sigaction(SIGUSR1, &action, NULL) == -1)
144		error("Can't catch SIGUSR1: %s", strerror(errno));
145#endif
146
147	printf("Listening on %s\n", device);
148	for (;;) {
149		packet_count = 0;
150		status = pcap_dispatch(pd, -1, countme,
151		    (u_char *)&packet_count);
152		if (status < 0)
153			break;
154		if (status != 0) {
155			printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
156			    status, packet_count);
157		} else
158			printf("No packets seen by pcap_dispatch\n");
159	}
160	if (status == PCAP_ERROR_BREAK) {
161		/*
162		 * We got interrupted, so perhaps we didn't
163		 * manage to finish a line we were printing.
164		 * Print an extra newline, just in case.
165		 */
166		putchar('\n');
167		printf("Loop got broken\n");
168	}
169	(void)fflush(stdout);
170	if (status == PCAP_ERROR) {
171		/*
172		 * Error.  Report it.
173		 */
174		(void)fprintf(stderr, "%s: pcap_dispatch: %s\n",
175		    program_name, pcap_geterr(pd));
176	}
177	return 0;
178}
179
180int
181main(int argc, char **argv)
182{
183	register int op;
184	register char *cp, *cmdbuf, *device;
185	int do_wakeup = 1;
186	pcap_if_t *devlist;
187	bpf_u_int32 localnet, netmask;
188	struct bpf_program fcode;
189	char ebuf[PCAP_ERRBUF_SIZE];
190	int status;
191	THREAD_HANDLE capture_thread;
192#ifndef _WIN32
193	void *retval;
194#endif
195
196	device = NULL;
197	if ((cp = strrchr(argv[0], '/')) != NULL)
198		program_name = cp + 1;
199	else
200		program_name = argv[0];
201
202	opterr = 0;
203	while ((op = getopt(argc, argv, "i:n")) != -1) {
204		switch (op) {
205
206		case 'i':
207			device = optarg;
208			break;
209
210		case 'n':
211			do_wakeup = 0;
212			break;
213
214		default:
215			usage();
216			/* NOTREACHED */
217		}
218	}
219
220	if (device == NULL) {
221		if (pcap_findalldevs(&devlist, ebuf) == -1)
222			error("%s", ebuf);
223		if (devlist == NULL)
224			error("no interfaces available for capture");
225		device = strdup(devlist->name);
226		pcap_freealldevs(devlist);
227	}
228	*ebuf = '\0';
229	pd = pcap_create(device, ebuf);
230	if (pd == NULL)
231		error("%s", ebuf);
232	status = pcap_set_snaplen(pd, 65535);
233	if (status != 0)
234		error("%s: pcap_set_snaplen failed: %s",
235			    device, pcap_statustostr(status));
236	status = pcap_set_timeout(pd, 5*60*1000);
237	if (status != 0)
238		error("%s: pcap_set_timeout failed: %s",
239		    device, pcap_statustostr(status));
240	status = pcap_activate(pd);
241	if (status < 0) {
242		/*
243		 * pcap_activate() failed.
244		 */
245		error("%s: %s\n(%s)", device,
246		    pcap_statustostr(status), pcap_geterr(pd));
247	} else if (status > 0) {
248		/*
249		 * pcap_activate() succeeded, but it's warning us
250		 * of a problem it had.
251		 */
252		warning("%s: %s\n(%s)", device,
253		    pcap_statustostr(status), pcap_geterr(pd));
254	}
255	if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
256		localnet = 0;
257		netmask = 0;
258		warning("%s", ebuf);
259	}
260	cmdbuf = copy_argv(&argv[optind]);
261
262	if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
263		error("%s", pcap_geterr(pd));
264
265	if (pcap_setfilter(pd, &fcode) < 0)
266		error("%s", pcap_geterr(pd));
267
268#ifdef _WIN32
269	capture_thread = CreateThread(NULL, 0, capture_thread_func, device,
270	    0, NULL);
271	if (capture_thread == NULL)
272		error("Can't create capture thread: %s",
273		    win32_strerror(GetLastError()));
274#else
275	status = pthread_create(&capture_thread, NULL, capture_thread_func,
276	    device);
277	if (status != 0)
278		error("Can't create capture thread: %s", strerror(status));
279#endif
280	sleep_secs(60);
281	printf("Doing pcap_breakloop()\n");
282	pcap_breakloop(pd);
283	if (do_wakeup) {
284		/*
285		 * Force a wakeup in the capture thread.
286		 *
287		 * On some platforms, with some devices,, pcap_breakloop()
288		 * can't do that itself.  On Windows, poke the device's
289		 * event handle; on UN*X, send a SIGUSR1 to the thread.
290		 */
291#ifdef _WIN32
292		printf("Setting event\n");
293		if (!SetEvent(pcap_getevent(pd)))
294			error("Can't set event for pcap_t: %s",
295			    win32_strerror(GetLastError()));
296#else
297		printf("Sending SIGUSR1\n");
298		status = pthread_kill(capture_thread, SIGUSR1);
299		if (status != 0)
300			warning("Can't interrupt capture thread: %s",
301			strerror(status));
302#endif
303	}
304
305	/*
306	 * Now wait for the capture thread to terminate.
307	 */
308#ifdef _WIN32
309	if (WaitForSingleObject(capture_thread, INFINITE) == WAIT_FAILED)
310		error("Wait for thread termination failed: %s",
311		    win32_strerror(GetLastError()));
312	CloseHandle(capture_thread);
313#else
314	status = pthread_join(capture_thread, &retval);
315	if (status != 0)
316		error("Wait for thread termination failed: %s",
317		    strerror(status));
318#endif
319
320	pcap_close(pd);
321	pcap_freecode(&fcode);
322	exit(status == -1 ? 1 : 0);
323}
324
325static void
326countme(u_char *user, const struct pcap_pkthdr *h _U_, const u_char *sp _U_)
327{
328	int *counterp = (int *)user;
329
330	(*counterp)++;
331}
332
333static void
334usage(void)
335{
336	(void)fprintf(stderr, "Usage: %s [ -n ] [ -i interface ] [ expression ]\n",
337	    program_name);
338	exit(1);
339}
340
341/* VARARGS */
342static void
343error(const char *fmt, ...)
344{
345	va_list ap;
346
347	(void)fprintf(stderr, "%s: ", program_name);
348	va_start(ap, fmt);
349	(void)vfprintf(stderr, fmt, ap);
350	va_end(ap);
351	if (*fmt) {
352		fmt += strlen(fmt);
353		if (fmt[-1] != '\n')
354			(void)fputc('\n', stderr);
355	}
356	exit(1);
357	/* NOTREACHED */
358}
359
360/* VARARGS */
361static void
362warning(const char *fmt, ...)
363{
364	va_list ap;
365
366	(void)fprintf(stderr, "%s: WARNING: ", program_name);
367	va_start(ap, fmt);
368	(void)vfprintf(stderr, fmt, ap);
369	va_end(ap);
370	if (*fmt) {
371		fmt += strlen(fmt);
372		if (fmt[-1] != '\n')
373			(void)fputc('\n', stderr);
374	}
375}
376
377/*
378 * Copy arg vector into a new buffer, concatenating arguments with spaces.
379 */
380static char *
381copy_argv(register char **argv)
382{
383	register char **p;
384	register size_t len = 0;
385	char *buf;
386	char *src, *dst;
387
388	p = argv;
389	if (*p == 0)
390		return 0;
391
392	while (*p)
393		len += strlen(*p++) + 1;
394
395	buf = (char *)malloc(len);
396	if (buf == NULL)
397		error("copy_argv: malloc");
398
399	p = argv;
400	dst = buf;
401	while ((src = *p++) != NULL) {
402		while ((*dst++ = *src++) != '\0')
403			;
404		dst[-1] = ' ';
405	}
406	dst[-1] = '\0';
407
408	return buf;
409}
410