xref: /freebsd/contrib/libpcap/pcap.c (revision 8cf6c252e716c4bba3d2e36b37e8df1762a07fc8)
18cf6c252SPaul Traina /*
28cf6c252SPaul Traina  * Copyright (c) 1993, 1994, 1995, 1996
38cf6c252SPaul Traina  *	The Regents of the University of California.  All rights reserved.
48cf6c252SPaul Traina  *
58cf6c252SPaul Traina  * Redistribution and use in source and binary forms, with or without
68cf6c252SPaul Traina  * modification, are permitted provided that the following conditions
78cf6c252SPaul Traina  * are met:
88cf6c252SPaul Traina  * 1. Redistributions of source code must retain the above copyright
98cf6c252SPaul Traina  *    notice, this list of conditions and the following disclaimer.
108cf6c252SPaul Traina  * 2. Redistributions in binary form must reproduce the above copyright
118cf6c252SPaul Traina  *    notice, this list of conditions and the following disclaimer in the
128cf6c252SPaul Traina  *    documentation and/or other materials provided with the distribution.
138cf6c252SPaul Traina  * 3. All advertising materials mentioning features or use of this software
148cf6c252SPaul Traina  *    must display the following acknowledgement:
158cf6c252SPaul Traina  *	This product includes software developed by the Computer Systems
168cf6c252SPaul Traina  *	Engineering Group at Lawrence Berkeley Laboratory.
178cf6c252SPaul Traina  * 4. Neither the name of the University nor of the Laboratory may be used
188cf6c252SPaul Traina  *    to endorse or promote products derived from this software without
198cf6c252SPaul Traina  *    specific prior written permission.
208cf6c252SPaul Traina  *
218cf6c252SPaul Traina  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
228cf6c252SPaul Traina  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
238cf6c252SPaul Traina  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
248cf6c252SPaul Traina  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
258cf6c252SPaul Traina  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
268cf6c252SPaul Traina  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
278cf6c252SPaul Traina  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
288cf6c252SPaul Traina  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
298cf6c252SPaul Traina  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
308cf6c252SPaul Traina  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
318cf6c252SPaul Traina  * SUCH DAMAGE.
328cf6c252SPaul Traina  */
338cf6c252SPaul Traina 
348cf6c252SPaul Traina #ifndef lint
358cf6c252SPaul Traina static char rcsid[] =
368cf6c252SPaul Traina     "@(#) $Header: pcap.c,v 1.25 96/06/05 21:45:26 leres Exp $ (LBL)";
378cf6c252SPaul Traina #endif
388cf6c252SPaul Traina 
398cf6c252SPaul Traina #include <sys/types.h>
408cf6c252SPaul Traina 
418cf6c252SPaul Traina #include <stdio.h>
428cf6c252SPaul Traina #include <stdlib.h>
438cf6c252SPaul Traina #include <string.h>
448cf6c252SPaul Traina #include <unistd.h>
458cf6c252SPaul Traina 
468cf6c252SPaul Traina #include "gnuc.h"
478cf6c252SPaul Traina #ifdef HAVE_OS_PROTO_H
488cf6c252SPaul Traina #include "os-proto.h"
498cf6c252SPaul Traina #endif
508cf6c252SPaul Traina 
518cf6c252SPaul Traina #include "pcap-int.h"
528cf6c252SPaul Traina 
538cf6c252SPaul Traina int
548cf6c252SPaul Traina pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
558cf6c252SPaul Traina {
568cf6c252SPaul Traina 	register int cc;
578cf6c252SPaul Traina 
588cf6c252SPaul Traina 	if (p->sf.rfile != NULL)
598cf6c252SPaul Traina 		return (pcap_offline_read(p, cnt, callback, user));
608cf6c252SPaul Traina 	/* XXX keep reading until we get something (or an error occurs) */
618cf6c252SPaul Traina 	do {
628cf6c252SPaul Traina 		cc = pcap_read(p, cnt, callback, user);
638cf6c252SPaul Traina 	} while (cc == 0);
648cf6c252SPaul Traina 	return (cc);
658cf6c252SPaul Traina }
668cf6c252SPaul Traina 
678cf6c252SPaul Traina int
688cf6c252SPaul Traina pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
698cf6c252SPaul Traina {
708cf6c252SPaul Traina 	for (;;) {
718cf6c252SPaul Traina 		int n = pcap_dispatch(p, cnt, callback, user);
728cf6c252SPaul Traina 		if (n <= 0)
738cf6c252SPaul Traina 			return (n);
748cf6c252SPaul Traina 		if (cnt > 0) {
758cf6c252SPaul Traina 			cnt -= n;
768cf6c252SPaul Traina 			if (cnt <= 0)
778cf6c252SPaul Traina 				return (0);
788cf6c252SPaul Traina 		}
798cf6c252SPaul Traina 	}
808cf6c252SPaul Traina }
818cf6c252SPaul Traina 
828cf6c252SPaul Traina struct singleton {
838cf6c252SPaul Traina 	struct pcap_pkthdr *hdr;
848cf6c252SPaul Traina 	const u_char *pkt;
858cf6c252SPaul Traina };
868cf6c252SPaul Traina 
878cf6c252SPaul Traina 
888cf6c252SPaul Traina static void
898cf6c252SPaul Traina pcap_oneshot(u_char *userData, const struct pcap_pkthdr *h, const u_char *pkt)
908cf6c252SPaul Traina {
918cf6c252SPaul Traina 	struct singleton *sp = (struct singleton *)userData;
928cf6c252SPaul Traina 	*sp->hdr = *h;
938cf6c252SPaul Traina 	sp->pkt = pkt;
948cf6c252SPaul Traina }
958cf6c252SPaul Traina 
968cf6c252SPaul Traina const u_char *
978cf6c252SPaul Traina pcap_next(pcap_t *p, struct pcap_pkthdr *h)
988cf6c252SPaul Traina {
998cf6c252SPaul Traina 	struct singleton s;
1008cf6c252SPaul Traina 
1018cf6c252SPaul Traina 	s.hdr = h;
1028cf6c252SPaul Traina 	if (pcap_dispatch(p, 1, pcap_oneshot, (u_char*)&s) <= 0)
1038cf6c252SPaul Traina 		return (0);
1048cf6c252SPaul Traina 	return (s.pkt);
1058cf6c252SPaul Traina }
1068cf6c252SPaul Traina 
1078cf6c252SPaul Traina int
1088cf6c252SPaul Traina pcap_datalink(pcap_t *p)
1098cf6c252SPaul Traina {
1108cf6c252SPaul Traina 	return (p->linktype);
1118cf6c252SPaul Traina }
1128cf6c252SPaul Traina 
1138cf6c252SPaul Traina int
1148cf6c252SPaul Traina pcap_snapshot(pcap_t *p)
1158cf6c252SPaul Traina {
1168cf6c252SPaul Traina 	return (p->snapshot);
1178cf6c252SPaul Traina }
1188cf6c252SPaul Traina 
1198cf6c252SPaul Traina int
1208cf6c252SPaul Traina pcap_is_swapped(pcap_t *p)
1218cf6c252SPaul Traina {
1228cf6c252SPaul Traina 	return (p->sf.swapped);
1238cf6c252SPaul Traina }
1248cf6c252SPaul Traina 
1258cf6c252SPaul Traina int
1268cf6c252SPaul Traina pcap_major_version(pcap_t *p)
1278cf6c252SPaul Traina {
1288cf6c252SPaul Traina 	return (p->sf.version_major);
1298cf6c252SPaul Traina }
1308cf6c252SPaul Traina 
1318cf6c252SPaul Traina int
1328cf6c252SPaul Traina pcap_minor_version(pcap_t *p)
1338cf6c252SPaul Traina {
1348cf6c252SPaul Traina 	return (p->sf.version_minor);
1358cf6c252SPaul Traina }
1368cf6c252SPaul Traina 
1378cf6c252SPaul Traina FILE *
1388cf6c252SPaul Traina pcap_file(pcap_t *p)
1398cf6c252SPaul Traina {
1408cf6c252SPaul Traina 	return (p->sf.rfile);
1418cf6c252SPaul Traina }
1428cf6c252SPaul Traina 
1438cf6c252SPaul Traina int
1448cf6c252SPaul Traina pcap_fileno(pcap_t *p)
1458cf6c252SPaul Traina {
1468cf6c252SPaul Traina 	return (p->fd);
1478cf6c252SPaul Traina }
1488cf6c252SPaul Traina 
1498cf6c252SPaul Traina void
1508cf6c252SPaul Traina pcap_perror(pcap_t *p, char *prefix)
1518cf6c252SPaul Traina {
1528cf6c252SPaul Traina 	fprintf(stderr, "%s: %s\n", prefix, p->errbuf);
1538cf6c252SPaul Traina }
1548cf6c252SPaul Traina 
1558cf6c252SPaul Traina char *
1568cf6c252SPaul Traina pcap_geterr(pcap_t *p)
1578cf6c252SPaul Traina {
1588cf6c252SPaul Traina 	return (p->errbuf);
1598cf6c252SPaul Traina }
1608cf6c252SPaul Traina 
1618cf6c252SPaul Traina /*
1628cf6c252SPaul Traina  * Not all systems have strerror().
1638cf6c252SPaul Traina  */
1648cf6c252SPaul Traina char *
1658cf6c252SPaul Traina pcap_strerror(int errnum)
1668cf6c252SPaul Traina {
1678cf6c252SPaul Traina #ifdef HAVE_STRERROR
1688cf6c252SPaul Traina 	return (strerror(errnum));
1698cf6c252SPaul Traina #else
1708cf6c252SPaul Traina 	extern int sys_nerr;
1718cf6c252SPaul Traina 	extern const char *const sys_errlist[];
1728cf6c252SPaul Traina 	static char ebuf[20];
1738cf6c252SPaul Traina 
1748cf6c252SPaul Traina 	if ((unsigned int)errnum < sys_nerr)
1758cf6c252SPaul Traina 		return ((char *)sys_errlist[errnum]);
1768cf6c252SPaul Traina 	(void)sprintf(ebuf, "Unknown error: %d", errnum);
1778cf6c252SPaul Traina 	return(ebuf);
1788cf6c252SPaul Traina #endif
1798cf6c252SPaul Traina }
1808cf6c252SPaul Traina 
1818cf6c252SPaul Traina void
1828cf6c252SPaul Traina pcap_close(pcap_t *p)
1838cf6c252SPaul Traina {
1848cf6c252SPaul Traina 	/*XXX*/
1858cf6c252SPaul Traina 	if (p->fd >= 0)
1868cf6c252SPaul Traina 		close(p->fd);
1878cf6c252SPaul Traina 	if (p->sf.rfile != NULL) {
1888cf6c252SPaul Traina 		(void)fclose(p->sf.rfile);
1898cf6c252SPaul Traina 		if (p->sf.base != NULL)
1908cf6c252SPaul Traina 			free(p->sf.base);
1918cf6c252SPaul Traina 	} else if (p->buffer != NULL)
1928cf6c252SPaul Traina 		free(p->buffer);
1938cf6c252SPaul Traina 
1948cf6c252SPaul Traina 	free(p);
1958cf6c252SPaul Traina }
196