15191Swollman/* 25191Swollman * Copyright (c) 1993, 1994, 1995, 1996, 1997 35191Swollman * The Regents of the University of California. All rights reserved. 45191Swollman * 55191Swollman * Redistribution and use in source and binary forms, with or without 65191Swollman * modification, are permitted provided that: (1) source code distributions 75191Swollman * retain the above copyright notice and this paragraph in its entirety, (2) 85191Swollman * distributions including binary code include the above copyright notice and 95191Swollman * this paragraph in its entirety in the documentation or other materials 105191Swollman * provided with the distribution, and (3) all advertising materials mentioning 115191Swollman * features or use of this software display the following acknowledgement: 125191Swollman * ``This product includes software developed by the University of California, 135191Swollman * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 145191Swollman * the University nor the names of its contributors may be used to endorse 155191Swollman * or promote products derived from this software without specific prior 165191Swollman * written permission. 175191Swollman * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 185191Swollman * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 195191Swollman * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 205191Swollman */ 215191Swollman#ifndef lint 225191Swollmanstatic const char rcsid[] _U_ = 235191Swollman "@(#) $Header: /tcpdump/master/libpcap/pcap-snoop.c,v 1.59 2008-12-02 16:25:14 guy Exp $ (LBL)"; 245191Swollman#endif 255191Swollman 265191Swollman#ifdef HAVE_CONFIG_H 275191Swollman#include "config.h" 285191Swollman#endif 295191Swollman 305191Swollman#include <sys/param.h> 315191Swollman#include <sys/file.h> 325191Swollman#include <sys/ioctl.h> 335191Swollman#include <sys/socket.h> 3450477Speter#include <sys/time.h> 355191Swollman 365191Swollman#include <net/raw.h> 375191Swollman#include <net/if.h> 385191Swollman 395191Swollman#include <netinet/in.h> 405191Swollman#include <netinet/in_systm.h> 415191Swollman#include <netinet/ip.h> 425191Swollman#include <netinet/if_ether.h> 435191Swollman#include <netinet/ip_var.h> 445191Swollman#include <netinet/udp.h> 4571862Speter#include <netinet/udp_var.h> 465191Swollman#include <netinet/tcp.h> 475191Swollman#include <netinet/tcpip.h> 4824204Sbde 495191Swollman#include <errno.h> 505191Swollman#include <stdio.h> 515191Swollman#include <stdlib.h> 525191Swollman#include <string.h> 535191Swollman#include <unistd.h> 545191Swollman 5532350Seivind#include "pcap-int.h" 5654263Sshin 575191Swollman#ifdef HAVE_OS_PROTO_H 585191Swollman#include "os-proto.h" 595191Swollman#endif 605191Swollman 615191Swollmanstatic int 625191Swollmanpcap_read_snoop(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 635191Swollman{ 6478351Smarkm int cc; 6510429Sbde register struct snoopheader *sh; 6678351Smarkm register u_int datalen; 6778351Smarkm register u_int caplen; 6878351Smarkm register u_char *cp; 6985074Sru 7078351Smarkmagain: 715191Swollman /* 725191Swollman * Has "pcap_breakloop()" been called? 7378351Smarkm */ 745191Swollman if (p->break_loop) { 7578351Smarkm /* 765191Swollman * Yes - clear the flag that indicates that it 775191Swollman * has, and return -2 to indicate that we were 785191Swollman * told to break out of the loop. 795191Swollman */ 8041757Seivind p->break_loop = 0; 8141757Seivind return (-2); 825191Swollman } 835191Swollman cc = read(p->fd, (char *)p->buffer, p->bufsize); 845191Swollman if (cc < 0) { 8553115Sphk /* Don't choke when we get ptraced */ 865191Swollman switch (errno) { 8713937Swollman 885191Swollman case EINTR: 895191Swollman goto again; 905191Swollman 9171862Speter case EWOULDBLOCK: 9271862Speter return (0); /* XXX */ 9371862Speter } 9471862Speter snprintf(p->errbuf, sizeof(p->errbuf), 9571862Speter "read: %s", pcap_strerror(errno)); 9671862Speter return (-1); 9771862Speter } 9871862Speter sh = (struct snoopheader *)p->buffer; 9971862Speter datalen = sh->snoop_packetlen; 10071862Speter 10171862Speter /* 10271862Speter * XXX - Sigh, snoop_packetlen is a 16 bit quantity. If we 10371862Speter * got a short length, but read a full sized snoop packet, 10471862Speter * assume we overflowed and add back the 64K... 10571862Speter */ 10671862Speter if (cc == (p->snapshot + sizeof(struct snoopheader)) && 10771862Speter (datalen < p->snapshot)) 10871862Speter datalen += (64 * 1024); 10971862Speter 11071862Speter caplen = (datalen < p->snapshot) ? datalen : p->snapshot; 11171862Speter cp = (u_char *)(sh + 1) + p->offset; /* XXX */ 11271862Speter 11378351Smarkm /* 11478351Smarkm * XXX unfortunately snoop loopback isn't exactly like 1155191Swollman * BSD's. The address family is encoded in the first 2 1165191Swollman * bytes rather than the first 4 bytes! Luckily the last 11741757Seivind * two snoop loopback bytes are zeroed. 11810957Swollman */ 11910957Swollman if (p->linktype == DLT_NULL && *((short *)(cp + 2)) == 0) { 12010957Swollman u_int *uip = (u_int *)cp; 12110957Swollman *uip >>= 16; 12210957Swollman } 12310957Swollman 12410957Swollman if (p->fcode.bf_insns == NULL || 12510957Swollman bpf_filter(p->fcode.bf_insns, cp, datalen, caplen)) { 12641757Seivind struct pcap_pkthdr h; 1275191Swollman ++p->md.stat.ps_recv; 1285191Swollman h.ts.tv_sec = sh->snoop_timestamp.tv_sec; 1295191Swollman h.ts.tv_usec = sh->snoop_timestamp.tv_usec; 1305191Swollman h.len = datalen; 1315191Swollman h.caplen = caplen; 1325191Swollman (*callback)(user, &h, cp); 1335191Swollman return (1); 1345191Swollman } 1355191Swollman return (0); 1365191Swollman} 1375191Swollman 1385191Swollmanstatic int 1395191Swollmanpcap_inject_snoop(pcap_t *p, const void *buf, size_t size) 1408876Srgrimes{ 14141757Seivind int ret; 1425191Swollman 1435191Swollman /* 1445191Swollman * XXX - libnet overwrites the source address with what I 1455191Swollman * presume is the interface's address; is that required? 1465191Swollman */ 1475191Swollman ret = write(p->fd, buf, size); 1485191Swollman if (ret == -1) { 1495191Swollman snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send: %s", 1505191Swollman pcap_strerror(errno)); 1515191Swollman return (-1); 1525191Swollman } 1535191Swollman return (ret); 15485074Sru} 1555191Swollman 1565191Swollmanstatic int 1575191Swollmanpcap_stats_snoop(pcap_t *p, struct pcap_stat *ps) 1585191Swollman{ 1595191Swollman register struct rawstats *rs; 1605191Swollman struct rawstats rawstats; 1615191Swollman 1625191Swollman rs = &rawstats; 16312611Sbde memset(rs, 0, sizeof(*rs)); 16478351Smarkm if (ioctl(p->fd, SIOCRAWSTATS, (char *)rs) < 0) { 1655191Swollman snprintf(p->errbuf, sizeof(p->errbuf), 16678351Smarkm "SIOCRAWSTATS: %s", pcap_strerror(errno)); 16778351Smarkm return (-1); 16878351Smarkm } 1695191Swollman 1705191Swollman /* 1715191Swollman * "ifdrops" are those dropped by the network interface 1725191Swollman * due to resource shortages or hardware errors. 1735191Swollman * 1745191Swollman * "sbdrops" are those dropped due to socket buffer limits. 1755191Swollman * 17641757Seivind * As filter is done in userland, "sbdrops" counts packets 1775191Swollman * regardless of whether they would've passed the filter. 1785191Swollman * 1795191Swollman * XXX - does this count *all* Snoop or Drain sockets, 1805191Swollman * rather than just this socket? If not, why does it have 1815191Swollman * both Snoop and Drain statistics? 1825191Swollman */ 1835191Swollman p->md.stat.ps_drop = 1845191Swollman rs->rs_snoop.ss_ifdrops + rs->rs_snoop.ss_sbdrops + 1855191Swollman rs->rs_drain.ds_ifdrops + rs->rs_drain.ds_sbdrops; 1865191Swollman 1875191Swollman /* 1885191Swollman * "ps_recv" counts only packets that passed the filter. 1895191Swollman * As filtering is done in userland, this does not include 1905191Swollman * packets dropped because we ran out of buffer space. 1915191Swollman */ 1925191Swollman *ps = p->md.stat; 1935191Swollman return (0); 19454263Sshin} 19554263Sshin 19654263Sshin/* XXX can't disable promiscuous */ 19754263Sshinstatic int 1985191Swollmanpcap_activate_snoop(pcap_t *p) 1995191Swollman{ 2005191Swollman int fd; 2015191Swollman struct sockaddr_raw sr; 2025191Swollman struct snoopfilter sf; 2035191Swollman u_int v; 2045191Swollman int ll_hdrlen; 2055191Swollman int snooplen; 2065191Swollman struct ifreq ifr; 2075191Swollman 2085191Swollman fd = socket(PF_RAW, SOCK_RAW, RAWPROTO_SNOOP); 2095191Swollman if (fd < 0) { 2105191Swollman snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snoop socket: %s", 2115191Swollman pcap_strerror(errno)); 21287912Sjlemon goto bad; 2135191Swollman } 214 p->fd = fd; 215 memset(&sr, 0, sizeof(sr)); 216 sr.sr_family = AF_RAW; 217 (void)strncpy(sr.sr_ifname, p->opt.source, sizeof(sr.sr_ifname)); 218 if (bind(fd, (struct sockaddr *)&sr, sizeof(sr))) { 219 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snoop bind: %s", 220 pcap_strerror(errno)); 221 goto bad; 222 } 223 memset(&sf, 0, sizeof(sf)); 224 if (ioctl(fd, SIOCADDSNOOP, &sf) < 0) { 225 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "SIOCADDSNOOP: %s", 226 pcap_strerror(errno)); 227 goto bad; 228 } 229 if (p->opt.buffer_size != 0) 230 v = p->opt.buffer_size; 231 else 232 v = 64 * 1024; /* default to 64K buffer size */ 233 (void)setsockopt(fd, SOL_SOCKET, SO_RCVBUF, (char *)&v, sizeof(v)); 234 /* 235 * XXX hack - map device name to link layer type 236 */ 237 if (strncmp("et", p->opt.source, 2) == 0 || /* Challenge 10 Mbit */ 238 strncmp("ec", p->opt.source, 2) == 0 || /* Indigo/Indy 10 Mbit, 239 O2 10/100 */ 240 strncmp("ef", p->opt.source, 2) == 0 || /* O200/2000 10/100 Mbit */ 241 strncmp("eg", p->opt.source, 2) == 0 || /* Octane/O2xxx/O3xxx Gigabit */ 242 strncmp("gfe", p->opt.source, 3) == 0 || /* GIO 100 Mbit */ 243 strncmp("fxp", p->opt.source, 3) == 0 || /* Challenge VME Enet */ 244 strncmp("ep", p->opt.source, 2) == 0 || /* Challenge 8x10 Mbit EPLEX */ 245 strncmp("vfe", p->opt.source, 3) == 0 || /* Challenge VME 100Mbit */ 246 strncmp("fa", p->opt.source, 2) == 0 || 247 strncmp("qaa", p->opt.source, 3) == 0 || 248 strncmp("cip", p->opt.source, 3) == 0 || 249 strncmp("el", p->opt.source, 2) == 0) { 250 p->linktype = DLT_EN10MB; 251 p->offset = RAW_HDRPAD(sizeof(struct ether_header)); 252 ll_hdrlen = sizeof(struct ether_header); 253 /* 254 * This is (presumably) a real Ethernet capture; give it a 255 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so 256 * that an application can let you choose it, in case you're 257 * capturing DOCSIS traffic that a Cisco Cable Modem 258 * Termination System is putting out onto an Ethernet (it 259 * doesn't put an Ethernet header onto the wire, it puts raw 260 * DOCSIS frames out on the wire inside the low-level 261 * Ethernet framing). 262 * 263 * XXX - are there any sorts of "fake Ethernet" that have 264 * Ethernet link-layer headers but that *shouldn't offer 265 * DLT_DOCSIS as a Cisco CMTS won't put traffic onto it 266 * or get traffic bridged onto it? "el" is for ATM LANE 267 * Ethernet devices, so that might be the case for them; 268 * the same applies for "qaa" classical IP devices. If 269 * "fa" devices are for FORE SPANS, that'd apply to them 270 * as well; what are "cip" devices - some other ATM 271 * Classical IP devices? 272 */ 273 p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2); 274 /* 275 * If that fails, just leave the list empty. 276 */ 277 if (p->dlt_list != NULL) { 278 p->dlt_list[0] = DLT_EN10MB; 279 p->dlt_list[1] = DLT_DOCSIS; 280 p->dlt_count = 2; 281 } 282 } else if (strncmp("ipg", p->opt.source, 3) == 0 || 283 strncmp("rns", p->opt.source, 3) == 0 || /* O2/200/2000 FDDI */ 284 strncmp("xpi", p->opt.source, 3) == 0) { 285 p->linktype = DLT_FDDI; 286 p->offset = 3; /* XXX yeah? */ 287 ll_hdrlen = 13; 288 } else if (strncmp("ppp", p->opt.source, 3) == 0) { 289 p->linktype = DLT_RAW; 290 ll_hdrlen = 0; /* DLT_RAW meaning "no PPP header, just the IP packet"? */ 291 } else if (strncmp("qfa", p->opt.source, 3) == 0) { 292 p->linktype = DLT_IP_OVER_FC; 293 ll_hdrlen = 24; 294 } else if (strncmp("pl", p->opt.source, 2) == 0) { 295 p->linktype = DLT_RAW; 296 ll_hdrlen = 0; /* Cray UNICOS/mp pseudo link */ 297 } else if (strncmp("lo", p->opt.source, 2) == 0) { 298 p->linktype = DLT_NULL; 299 ll_hdrlen = 4; 300 } else { 301 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 302 "snoop: unknown physical layer type"); 303 goto bad; 304 } 305 306 if (p->opt.rfmon) { 307 /* 308 * No monitor mode on Irix (no Wi-Fi devices on 309 * hardware supported by Irix). 310 */ 311 return (PCAP_ERROR_RFMON_NOTSUP); 312 } 313 314#ifdef SIOCGIFMTU 315 /* 316 * XXX - IRIX appears to give you an error if you try to set the 317 * capture length to be greater than the MTU, so let's try to get 318 * the MTU first and, if that succeeds, trim the snap length 319 * to be no greater than the MTU. 320 */ 321 (void)strncpy(ifr.ifr_name, p->opt.source, sizeof(ifr.ifr_name)); 322 if (ioctl(fd, SIOCGIFMTU, (char *)&ifr) < 0) { 323 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "SIOCGIFMTU: %s", 324 pcap_strerror(errno)); 325 goto bad; 326 } 327 /* 328 * OK, we got it. 329 * 330 * XXX - some versions of IRIX 6.5 define "ifr_mtu" and have an 331 * "ifru_metric" member of the "ifr_ifru" union in an "ifreq" 332 * structure, others don't. 333 * 334 * I've no idea what's going on, so, if "ifr_mtu" isn't defined, 335 * we define it as "ifr_metric", as using that field appears to 336 * work on the versions that lack "ifr_mtu" (and, on those that 337 * don't lack it, "ifru_metric" and "ifru_mtu" are both "int" 338 * members of the "ifr_ifru" union, which suggests that they 339 * may be interchangeable in this case). 340 */ 341#ifndef ifr_mtu 342#define ifr_mtu ifr_metric 343#endif 344 if (p->snapshot > ifr.ifr_mtu + ll_hdrlen) 345 p->snapshot = ifr.ifr_mtu + ll_hdrlen; 346#endif 347 348 /* 349 * The argument to SIOCSNOOPLEN is the number of link-layer 350 * payload bytes to capture - it doesn't count link-layer 351 * header bytes. 352 */ 353 snooplen = p->snapshot - ll_hdrlen; 354 if (snooplen < 0) 355 snooplen = 0; 356 if (ioctl(fd, SIOCSNOOPLEN, &snooplen) < 0) { 357 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "SIOCSNOOPLEN: %s", 358 pcap_strerror(errno)); 359 goto bad; 360 } 361 v = 1; 362 if (ioctl(fd, SIOCSNOOPING, &v) < 0) { 363 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "SIOCSNOOPING: %s", 364 pcap_strerror(errno)); 365 goto bad; 366 } 367 368 p->bufsize = 4096; /* XXX */ 369 p->buffer = (u_char *)malloc(p->bufsize); 370 if (p->buffer == NULL) { 371 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", 372 pcap_strerror(errno)); 373 goto bad; 374 } 375 376 /* 377 * "p->fd" is a socket, so "select()" should work on it. 378 */ 379 p->selectable_fd = p->fd; 380 381 p->read_op = pcap_read_snoop; 382 p->inject_op = pcap_inject_snoop; 383 p->setfilter_op = install_bpf_program; /* no kernel filtering */ 384 p->setdirection_op = NULL; /* Not implemented. */ 385 p->set_datalink_op = NULL; /* can't change data link type */ 386 p->getnonblock_op = pcap_getnonblock_fd; 387 p->setnonblock_op = pcap_setnonblock_fd; 388 p->stats_op = pcap_stats_snoop; 389 390 return (0); 391 bad: 392 pcap_cleanup_live_common(p); 393 return (PCAP_ERROR); 394} 395 396pcap_t * 397pcap_create_interface(const char *device, char *ebuf) 398{ 399 pcap_t *p; 400 401 p = pcap_create_common(device, ebuf); 402 if (p == NULL) 403 return (NULL); 404 405 p->activate_op = pcap_activate_snoop; 406 return (p); 407} 408 409int 410pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf) 411{ 412 return (0); 413} 414