2 * Copyright (c) 1993, 1994, 1995, 1996, 1997
3 * The Regents of the University of California. All rights reserved.
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
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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
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.
22 static const char rcsid[] _U_ =
23 "@(#) $Header: /tcpdump/master/libpcap/pcap-snoop.c,v 1.45.2.5 2004/03/21 08:33:24 guy Exp $ (LBL)";
30 #include <sys/param.h>
32 #include <sys/ioctl.h>
33 #include <sys/socket.h>
39 #include <netinet/in.h>
40 #include <netinet/in_systm.h>
41 #include <netinet/ip.h>
42 #include <netinet/if_ether.h>
43 #include <netinet/ip_var.h>
44 #include <netinet/udp.h>
45 #include <netinet/udp_var.h>
46 #include <netinet/tcp.h>
47 #include <netinet/tcpip.h>
57 #ifdef HAVE_OS_PROTO_H
62 pcap_read_snoop(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
65 register struct snoopheader *sh;
72 * Has "pcap_breakloop()" been called?
76 * Yes - clear the flag that indicates that it
77 * has, and return -2 to indicate that we were
78 * told to break out of the loop.
83 cc = read(p->fd, (char *)p->buffer, p->bufsize);
85 /* Don't choke when we get ptraced */
94 snprintf(p->errbuf, sizeof(p->errbuf),
95 "read: %s", pcap_strerror(errno));
98 sh = (struct snoopheader *)p->buffer;
99 datalen = sh->snoop_packetlen;
100 caplen = (datalen < p->snapshot) ? datalen : p->snapshot;
101 cp = (u_char *)(sh + 1) + p->offset; /* XXX */
104 * XXX unfortunately snoop loopback isn't exactly like
105 * BSD's. The address family is encoded in the first 2
106 * bytes rather than the first 4 bytes! Luckily the last
107 * two snoop loopback bytes are zeroed.
109 if (p->linktype == DLT_NULL && *((short *)(cp + 2)) == 0) {
110 u_int *uip = (u_int *)cp;
114 if (p->fcode.bf_insns == NULL ||
115 bpf_filter(p->fcode.bf_insns, cp, datalen, caplen)) {
116 struct pcap_pkthdr h;
117 ++p->md.stat.ps_recv;
118 h.ts.tv_sec = sh->snoop_timestamp.tv_sec;
119 h.ts.tv_usec = sh->snoop_timestamp.tv_usec;
122 (*callback)(user, &h, cp);
129 pcap_stats_snoop(pcap_t *p, struct pcap_stat *ps)
131 register struct rawstats *rs;
132 struct rawstats rawstats;
135 memset(rs, 0, sizeof(*rs));
136 if (ioctl(p->fd, SIOCRAWSTATS, (char *)rs) < 0) {
137 snprintf(p->errbuf, sizeof(p->errbuf),
138 "SIOCRAWSTATS: %s", pcap_strerror(errno));
143 * "ifdrops" are those dropped by the network interface
144 * due to resource shortages or hardware errors.
146 * "sbdrops" are those dropped due to socket buffer limits.
148 * As filter is done in userland, "sbdrops" counts packets
149 * regardless of whether they would've passed the filter.
151 * XXX - does this count *all* Snoop or Drain sockets,
152 * rather than just this socket? If not, why does it have
153 * both Snoop and Drain statistics?
156 rs->rs_snoop.ss_ifdrops + rs->rs_snoop.ss_sbdrops +
157 rs->rs_drain.ds_ifdrops + rs->rs_drain.ds_sbdrops;
160 * "ps_recv" counts only packets that passed the filter.
161 * As filtering is done in userland, this does not include
162 * packets dropped because we ran out of buffer space.
169 pcap_close_snoop(pcap_t *p)
171 if (p->buffer != NULL)
177 /* XXX can't disable promiscuous */
179 pcap_open_live(const char *device, int snaplen, int promisc, int to_ms,
183 struct sockaddr_raw sr;
184 struct snoopfilter sf;
191 p = (pcap_t *)malloc(sizeof(*p));
193 snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
194 pcap_strerror(errno));
197 memset(p, 0, sizeof(*p));
198 fd = socket(PF_RAW, SOCK_RAW, RAWPROTO_SNOOP);
200 snprintf(ebuf, PCAP_ERRBUF_SIZE, "snoop socket: %s",
201 pcap_strerror(errno));
205 memset(&sr, 0, sizeof(sr));
206 sr.sr_family = AF_RAW;
207 (void)strncpy(sr.sr_ifname, device, sizeof(sr.sr_ifname));
208 if (bind(fd, (struct sockaddr *)&sr, sizeof(sr))) {
209 snprintf(ebuf, PCAP_ERRBUF_SIZE, "snoop bind: %s",
210 pcap_strerror(errno));
213 memset(&sf, 0, sizeof(sf));
214 if (ioctl(fd, SIOCADDSNOOP, &sf) < 0) {
215 snprintf(ebuf, PCAP_ERRBUF_SIZE, "SIOCADDSNOOP: %s",
216 pcap_strerror(errno));
220 (void)setsockopt(fd, SOL_SOCKET, SO_RCVBUF, (char *)&v, sizeof(v));
222 * XXX hack - map device name to link layer type
224 if (strncmp("et", device, 2) == 0 || /* Challenge 10 Mbit */
225 strncmp("ec", device, 2) == 0 || /* Indigo/Indy 10 Mbit,
227 strncmp("ef", device, 2) == 0 || /* O200/2000 10/100 Mbit */
228 strncmp("eg", device, 2) == 0 || /* Octane/O2xxx/O3xxx Gigabit */
229 strncmp("gfe", device, 3) == 0 || /* GIO 100 Mbit */
230 strncmp("fxp", device, 3) == 0 || /* Challenge VME Enet */
231 strncmp("ep", device, 2) == 0 || /* Challenge 8x10 Mbit EPLEX */
232 strncmp("vfe", device, 3) == 0 || /* Challenge VME 100Mbit */
233 strncmp("fa", device, 2) == 0 ||
234 strncmp("qaa", device, 3) == 0 ||
235 strncmp("cip", device, 3) == 0 ||
236 strncmp("el", device, 2) == 0) {
237 p->linktype = DLT_EN10MB;
238 p->offset = RAW_HDRPAD(sizeof(struct ether_header));
239 ll_hdrlen = sizeof(struct ether_header);
240 } else if (strncmp("ipg", device, 3) == 0 ||
241 strncmp("rns", device, 3) == 0 || /* O2/200/2000 FDDI */
242 strncmp("xpi", device, 3) == 0) {
243 p->linktype = DLT_FDDI;
244 p->offset = 3; /* XXX yeah? */
246 } else if (strncmp("ppp", device, 3) == 0) {
247 p->linktype = DLT_RAW;
248 ll_hdrlen = 0; /* DLT_RAW meaning "no PPP header, just the IP packet"? */
249 } else if (strncmp("qfa", device, 3) == 0) {
250 p->linktype = DLT_IP_OVER_FC;
252 } else if (strncmp("pl", device, 2) == 0) {
253 p->linktype = DLT_RAW;
254 ll_hdrlen = 0; /* Cray UNICOS/mp pseudo link */
255 } else if (strncmp("lo", device, 2) == 0) {
256 p->linktype = DLT_NULL;
259 snprintf(ebuf, PCAP_ERRBUF_SIZE,
260 "snoop: unknown physical layer type");
265 * XXX - IRIX appears to give you an error if you try to set the
266 * capture length to be greater than the MTU, so let's try to get
267 * the MTU first and, if that succeeds, trim the snap length
268 * to be no greater than the MTU.
270 (void)strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
271 if (ioctl(fd, SIOCGIFMTU, (char *)&ifr) < 0) {
272 snprintf(ebuf, PCAP_ERRBUF_SIZE, "SIOCGIFMTU: %s",
273 pcap_strerror(errno));
279 * XXX - some versions of IRIX 6.5 define "ifr_mtu" and have an
280 * "ifru_metric" member of the "ifr_ifru" union in an "ifreq"
281 * structure, others don't.
283 * I've no idea what's going on, so, if "ifr_mtu" isn't defined,
284 * we define it as "ifr_metric", as using that field appears to
285 * work on the versions that lack "ifr_mtu" (and, on those that
286 * don't lack it, "ifru_metric" and "ifru_mtu" are both "int"
287 * members of the "ifr_ifru" union, which suggests that they
288 * may be interchangeable in this case).
291 #define ifr_mtu ifr_metric
293 if (snaplen > ifr.ifr_mtu + ll_hdrlen)
294 snaplen = ifr.ifr_mtu + ll_hdrlen;
298 * The argument to SIOCSNOOPLEN is the number of link-layer
299 * payload bytes to capture - it doesn't count link-layer
302 snooplen = snaplen - ll_hdrlen;
305 if (ioctl(fd, SIOCSNOOPLEN, &snooplen) < 0) {
306 snprintf(ebuf, PCAP_ERRBUF_SIZE, "SIOCSNOOPLEN: %s",
307 pcap_strerror(errno));
310 p->snapshot = snaplen;
312 if (ioctl(fd, SIOCSNOOPING, &v) < 0) {
313 snprintf(ebuf, PCAP_ERRBUF_SIZE, "SIOCSNOOPING: %s",
314 pcap_strerror(errno));
318 p->bufsize = 4096; /* XXX */
319 p->buffer = (u_char *)malloc(p->bufsize);
320 if (p->buffer == NULL) {
321 snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
322 pcap_strerror(errno));
327 * "p->fd" is a socket, so "select()" should work on it.
329 p->selectable_fd = p->fd;
331 p->read_op = pcap_read_snoop;
332 p->setfilter_op = install_bpf_program; /* no kernel filtering */
333 p->set_datalink_op = NULL; /* can't change data link type */
334 p->getnonblock_op = pcap_getnonblock_fd;
335 p->setnonblock_op = pcap_setnonblock_fd;
336 p->stats_op = pcap_stats_snoop;
337 p->close_op = pcap_close_snoop;
347 pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)