1 /* 2 * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998 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 the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the Computer Systems 16 * Engineering Group at Lawrence Berkeley Laboratory. 17 * 4. Neither the name of the University nor of the Laboratory may be used 18 * to endorse or promote products derived from this software without 19 * specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 static const char rcsid[] _U_ = 36 "@(#) $Header: /tcpdump/master/libpcap/pcap.c,v 1.88.2.19 2007/09/19 02:50:52 guy Exp $ (LBL)"; 37 #endif 38 39 #ifdef HAVE_CONFIG_H 40 #include "config.h" 41 #endif 42 43 #ifdef WIN32 44 #include <pcap-stdinc.h> 45 #else /* WIN32 */ 46 #include <sys/types.h> 47 #include <sys/mman.h> 48 #endif /* WIN32 */ 49 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <string.h> 53 #if !defined(_MSC_VER) && !defined(__BORLANDC__) 54 #include <unistd.h> 55 #endif 56 #include <fcntl.h> 57 #include <errno.h> 58 59 #ifdef HAVE_OS_PROTO_H 60 #include "os-proto.h" 61 #endif 62 63 #ifdef MSDOS 64 #include "pcap-dos.h" 65 #endif 66 67 #include "pcap-int.h" 68 69 #ifdef HAVE_DAG_API 70 #include <dagnew.h> 71 #include <dagapi.h> 72 #endif 73 74 int 75 pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 76 { 77 78 return p->read_op(p, cnt, callback, user); 79 } 80 81 /* 82 * XXX - is this necessary? 83 */ 84 int 85 pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 86 { 87 88 return p->read_op(p, cnt, callback, user); 89 } 90 91 int 92 pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 93 { 94 register int n; 95 96 for (;;) { 97 if (p->sf.rfile != NULL) { 98 /* 99 * 0 means EOF, so don't loop if we get 0. 100 */ 101 n = pcap_offline_read(p, cnt, callback, user); 102 } else { 103 /* 104 * XXX keep reading until we get something 105 * (or an error occurs) 106 */ 107 do { 108 n = p->read_op(p, cnt, callback, user); 109 } while (n == 0); 110 } 111 if (n <= 0) 112 return (n); 113 if (cnt > 0) { 114 cnt -= n; 115 if (cnt <= 0) 116 return (0); 117 } 118 } 119 } 120 121 struct singleton { 122 struct pcap_pkthdr *hdr; 123 const u_char *pkt; 124 }; 125 126 127 static void 128 pcap_oneshot(u_char *userData, const struct pcap_pkthdr *h, const u_char *pkt) 129 { 130 struct singleton *sp = (struct singleton *)userData; 131 *sp->hdr = *h; 132 sp->pkt = pkt; 133 } 134 135 const u_char * 136 pcap_next(pcap_t *p, struct pcap_pkthdr *h) 137 { 138 struct singleton s; 139 140 s.hdr = h; 141 if (pcap_dispatch(p, 1, pcap_oneshot, (u_char*)&s) <= 0) 142 return (0); 143 return (s.pkt); 144 } 145 146 struct pkt_for_fakecallback { 147 struct pcap_pkthdr *hdr; 148 const u_char **pkt; 149 }; 150 151 static void 152 pcap_fakecallback(u_char *userData, const struct pcap_pkthdr *h, 153 const u_char *pkt) 154 { 155 struct pkt_for_fakecallback *sp = (struct pkt_for_fakecallback *)userData; 156 157 *sp->hdr = *h; 158 *sp->pkt = pkt; 159 } 160 161 int 162 pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header, 163 const u_char **pkt_data) 164 { 165 struct pkt_for_fakecallback s; 166 167 s.hdr = &p->pcap_header; 168 s.pkt = pkt_data; 169 170 /* Saves a pointer to the packet headers */ 171 *pkt_header= &p->pcap_header; 172 173 if (p->sf.rfile != NULL) { 174 int status; 175 176 /* We are on an offline capture */ 177 status = pcap_offline_read(p, 1, pcap_fakecallback, 178 (u_char *)&s); 179 180 /* 181 * Return codes for pcap_offline_read() are: 182 * - 0: EOF 183 * - -1: error 184 * - >1: OK 185 * The first one ('0') conflicts with the return code of 186 * 0 from pcap_read() meaning "no packets arrived before 187 * the timeout expired", so we map it to -2 so you can 188 * distinguish between an EOF from a savefile and a 189 * "no packets arrived before the timeout expired, try 190 * again" from a live capture. 191 */ 192 if (status == 0) 193 return (-2); 194 else 195 return (status); 196 } 197 198 /* 199 * Return codes for pcap_read() are: 200 * - 0: timeout 201 * - -1: error 202 * - -2: loop was broken out of with pcap_breakloop() 203 * - >1: OK 204 * The first one ('0') conflicts with the return code of 0 from 205 * pcap_offline_read() meaning "end of file". 206 */ 207 return (p->read_op(p, 1, pcap_fakecallback, (u_char *)&s)); 208 } 209 210 /* 211 * Force the loop in "pcap_read()" or "pcap_read_offline()" to terminate. 212 */ 213 void 214 pcap_breakloop(pcap_t *p) 215 { 216 p->break_loop = 1; 217 } 218 219 int 220 pcap_datalink(pcap_t *p) 221 { 222 return (p->linktype); 223 } 224 225 int 226 pcap_list_datalinks(pcap_t *p, int **dlt_buffer) 227 { 228 if (p->dlt_count == 0) { 229 /* 230 * We couldn't fetch the list of DLTs, which means 231 * this platform doesn't support changing the 232 * DLT for an interface. Return a list of DLTs 233 * containing only the DLT this device supports. 234 */ 235 *dlt_buffer = (int*)malloc(sizeof(**dlt_buffer)); 236 if (*dlt_buffer == NULL) { 237 (void)snprintf(p->errbuf, sizeof(p->errbuf), 238 "malloc: %s", pcap_strerror(errno)); 239 return (-1); 240 } 241 **dlt_buffer = p->linktype; 242 return (1); 243 } else { 244 *dlt_buffer = (int*)calloc(sizeof(**dlt_buffer), p->dlt_count); 245 if (*dlt_buffer == NULL) { 246 (void)snprintf(p->errbuf, sizeof(p->errbuf), 247 "malloc: %s", pcap_strerror(errno)); 248 return (-1); 249 } 250 (void)memcpy(*dlt_buffer, p->dlt_list, 251 sizeof(**dlt_buffer) * p->dlt_count); 252 return (p->dlt_count); 253 } 254 } 255 256 int 257 pcap_set_datalink(pcap_t *p, int dlt) 258 { 259 int i; 260 const char *dlt_name; 261 262 if (p->dlt_count == 0 || p->set_datalink_op == NULL) { 263 /* 264 * We couldn't fetch the list of DLTs, or we don't 265 * have a "set datalink" operation, which means 266 * this platform doesn't support changing the 267 * DLT for an interface. Check whether the new 268 * DLT is the one this interface supports. 269 */ 270 if (p->linktype != dlt) 271 goto unsupported; 272 273 /* 274 * It is, so there's nothing we need to do here. 275 */ 276 return (0); 277 } 278 for (i = 0; i < p->dlt_count; i++) 279 if (p->dlt_list[i] == dlt) 280 break; 281 if (i >= p->dlt_count) 282 goto unsupported; 283 if (p->dlt_count == 2 && p->dlt_list[0] == DLT_EN10MB && 284 dlt == DLT_DOCSIS) { 285 /* 286 * This is presumably an Ethernet device, as the first 287 * link-layer type it offers is DLT_EN10MB, and the only 288 * other type it offers is DLT_DOCSIS. That means that 289 * we can't tell the driver to supply DOCSIS link-layer 290 * headers - we're just pretending that's what we're 291 * getting, as, presumably, we're capturing on a dedicated 292 * link to a Cisco Cable Modem Termination System, and 293 * it's putting raw DOCSIS frames on the wire inside low-level 294 * Ethernet framing. 295 */ 296 p->linktype = dlt; 297 return (0); 298 } 299 if (p->set_datalink_op(p, dlt) == -1) 300 return (-1); 301 p->linktype = dlt; 302 return (0); 303 304 unsupported: 305 dlt_name = pcap_datalink_val_to_name(dlt); 306 if (dlt_name != NULL) { 307 (void) snprintf(p->errbuf, sizeof(p->errbuf), 308 "%s is not one of the DLTs supported by this device", 309 dlt_name); 310 } else { 311 (void) snprintf(p->errbuf, sizeof(p->errbuf), 312 "DLT %d is not one of the DLTs supported by this device", 313 dlt); 314 } 315 return (-1); 316 } 317 318 struct dlt_choice { 319 const char *name; 320 const char *description; 321 int dlt; 322 }; 323 324 #define DLT_CHOICE(code, description) { #code, description, code } 325 #define DLT_CHOICE_SENTINEL { NULL, NULL, 0 } 326 327 static struct dlt_choice dlt_choices[] = { 328 DLT_CHOICE(DLT_NULL, "BSD loopback"), 329 DLT_CHOICE(DLT_EN10MB, "Ethernet"), 330 DLT_CHOICE(DLT_IEEE802, "Token ring"), 331 DLT_CHOICE(DLT_ARCNET, "ARCNET"), 332 DLT_CHOICE(DLT_SLIP, "SLIP"), 333 DLT_CHOICE(DLT_PPP, "PPP"), 334 DLT_CHOICE(DLT_FDDI, "FDDI"), 335 DLT_CHOICE(DLT_ATM_RFC1483, "RFC 1483 LLC-encapsulated ATM"), 336 DLT_CHOICE(DLT_RAW, "Raw IP"), 337 DLT_CHOICE(DLT_SLIP_BSDOS, "BSD/OS SLIP"), 338 DLT_CHOICE(DLT_PPP_BSDOS, "BSD/OS PPP"), 339 DLT_CHOICE(DLT_ATM_CLIP, "Linux Classical IP-over-ATM"), 340 DLT_CHOICE(DLT_PPP_SERIAL, "PPP over serial"), 341 DLT_CHOICE(DLT_PPP_ETHER, "PPPoE"), 342 DLT_CHOICE(DLT_C_HDLC, "Cisco HDLC"), 343 DLT_CHOICE(DLT_IEEE802_11, "802.11"), 344 DLT_CHOICE(DLT_FRELAY, "Frame Relay"), 345 DLT_CHOICE(DLT_LOOP, "OpenBSD loopback"), 346 DLT_CHOICE(DLT_ENC, "OpenBSD encapsulated IP"), 347 DLT_CHOICE(DLT_LINUX_SLL, "Linux cooked"), 348 DLT_CHOICE(DLT_LTALK, "Localtalk"), 349 DLT_CHOICE(DLT_PFLOG, "OpenBSD pflog file"), 350 DLT_CHOICE(DLT_PRISM_HEADER, "802.11 plus Prism header"), 351 DLT_CHOICE(DLT_IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"), 352 DLT_CHOICE(DLT_SUNATM, "Sun raw ATM"), 353 DLT_CHOICE(DLT_IEEE802_11_RADIO, "802.11 plus BSD radio information header"), 354 DLT_CHOICE(DLT_APPLE_IP_OVER_IEEE1394, "Apple IP-over-IEEE 1394"), 355 DLT_CHOICE(DLT_ARCNET_LINUX, "Linux ARCNET"), 356 DLT_CHOICE(DLT_DOCSIS, "DOCSIS"), 357 DLT_CHOICE(DLT_LINUX_IRDA, "Linux IrDA"), 358 DLT_CHOICE(DLT_LINUX_LAPD, "Linux vISDN LAPD"), 359 DLT_CHOICE(DLT_IEEE802_11_RADIO_AVS, "802.11 plus AVS radio information header"), 360 DLT_CHOICE(DLT_SYMANTEC_FIREWALL, "Symantec Firewall"), 361 DLT_CHOICE(DLT_JUNIPER_ATM1, "Juniper ATM1 PIC"), 362 DLT_CHOICE(DLT_JUNIPER_ATM2, "Juniper ATM2 PIC"), 363 DLT_CHOICE(DLT_JUNIPER_MLPPP, "Juniper Multi-Link PPP"), 364 DLT_CHOICE(DLT_PPP_PPPD, "PPP for pppd, with direction flag"), 365 DLT_CHOICE(DLT_JUNIPER_PPPOE, "Juniper PPPoE"), 366 DLT_CHOICE(DLT_JUNIPER_PPPOE_ATM, "Juniper PPPoE/ATM"), 367 DLT_CHOICE(DLT_GPRS_LLC, "GPRS LLC"), 368 DLT_CHOICE(DLT_GPF_T, "GPF-T"), 369 DLT_CHOICE(DLT_GPF_F, "GPF-F"), 370 DLT_CHOICE(DLT_JUNIPER_PIC_PEER, "Juniper PIC Peer"), 371 DLT_CHOICE(DLT_JUNIPER_MLFR, "Juniper Multi-Link Frame Relay"), 372 DLT_CHOICE(DLT_ERF_ETH, "Ethernet with Endace ERF header"), 373 DLT_CHOICE(DLT_ERF_POS, "Packet-over-SONET with Endace ERF header"), 374 DLT_CHOICE(DLT_JUNIPER_GGSN, "Juniper GGSN PIC"), 375 DLT_CHOICE(DLT_JUNIPER_ES, "Juniper Encryption Services PIC"), 376 DLT_CHOICE(DLT_JUNIPER_MONITOR, "Juniper Passive Monitor PIC"), 377 DLT_CHOICE(DLT_JUNIPER_SERVICES, "Juniper Advanced Services PIC"), 378 DLT_CHOICE(DLT_JUNIPER_MFR, "Juniper FRF.16 Frame Relay"), 379 DLT_CHOICE(DLT_JUNIPER_ETHER, "Juniper Ethernet"), 380 DLT_CHOICE(DLT_JUNIPER_PPP, "Juniper PPP"), 381 DLT_CHOICE(DLT_JUNIPER_FRELAY, "Juniper Frame Relay"), 382 DLT_CHOICE(DLT_JUNIPER_CHDLC, "Juniper C-HDLC"), 383 DLT_CHOICE(DLT_MFR, "FRF.16 Frame Relay"), 384 DLT_CHOICE(DLT_JUNIPER_VP, "Juniper Voice PIC"), 385 DLT_CHOICE(DLT_MTP2, "SS7 MTP2"), 386 DLT_CHOICE(DLT_A429, "Arinc 429"), 387 DLT_CHOICE(DLT_A653_ICM, "Arinc 653 Interpartition Communication"), 388 DLT_CHOICE(DLT_USB, "USB"), 389 DLT_CHOICE(DLT_BLUETOOTH_HCI_H4, "Bluetooth HCI UART transport layer"), 390 DLT_CHOICE(DLT_CAN20B, "Controller Area Network (CAN) v. 2.0B"), 391 DLT_CHOICE(DLT_MTP2_WITH_PHDR, "SS7 MTP2 with Pseudo-header"), 392 DLT_CHOICE_SENTINEL 393 }; 394 395 /* 396 * This array is designed for mapping upper and lower case letter 397 * together for a case independent comparison. The mappings are 398 * based upon ascii character sequences. 399 */ 400 static const u_char charmap[] = { 401 (u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003', 402 (u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007', 403 (u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013', 404 (u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017', 405 (u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023', 406 (u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027', 407 (u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033', 408 (u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037', 409 (u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043', 410 (u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047', 411 (u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053', 412 (u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057', 413 (u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063', 414 (u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067', 415 (u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073', 416 (u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077', 417 (u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143', 418 (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147', 419 (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153', 420 (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157', 421 (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163', 422 (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167', 423 (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133', 424 (u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137', 425 (u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143', 426 (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147', 427 (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153', 428 (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157', 429 (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163', 430 (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167', 431 (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173', 432 (u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177', 433 (u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203', 434 (u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207', 435 (u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213', 436 (u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217', 437 (u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223', 438 (u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227', 439 (u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233', 440 (u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237', 441 (u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243', 442 (u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247', 443 (u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253', 444 (u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257', 445 (u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263', 446 (u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267', 447 (u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273', 448 (u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277', 449 (u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343', 450 (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347', 451 (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353', 452 (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357', 453 (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363', 454 (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367', 455 (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333', 456 (u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337', 457 (u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343', 458 (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347', 459 (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353', 460 (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357', 461 (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363', 462 (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367', 463 (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373', 464 (u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377', 465 }; 466 467 int 468 pcap_strcasecmp(const char *s1, const char *s2) 469 { 470 register const u_char *cm = charmap, 471 *us1 = (const u_char *)s1, 472 *us2 = (const u_char *)s2; 473 474 while (cm[*us1] == cm[*us2++]) 475 if (*us1++ == '\0') 476 return(0); 477 return (cm[*us1] - cm[*--us2]); 478 } 479 480 int 481 pcap_datalink_name_to_val(const char *name) 482 { 483 int i; 484 485 for (i = 0; dlt_choices[i].name != NULL; i++) { 486 if (pcap_strcasecmp(dlt_choices[i].name + sizeof("DLT_") - 1, 487 name) == 0) 488 return (dlt_choices[i].dlt); 489 } 490 return (-1); 491 } 492 493 const char * 494 pcap_datalink_val_to_name(int dlt) 495 { 496 int i; 497 498 for (i = 0; dlt_choices[i].name != NULL; i++) { 499 if (dlt_choices[i].dlt == dlt) 500 return (dlt_choices[i].name + sizeof("DLT_") - 1); 501 } 502 return (NULL); 503 } 504 505 const char * 506 pcap_datalink_val_to_description(int dlt) 507 { 508 int i; 509 510 for (i = 0; dlt_choices[i].name != NULL; i++) { 511 if (dlt_choices[i].dlt == dlt) 512 return (dlt_choices[i].description); 513 } 514 return (NULL); 515 } 516 517 int 518 pcap_snapshot(pcap_t *p) 519 { 520 return (p->snapshot); 521 } 522 523 int 524 pcap_is_swapped(pcap_t *p) 525 { 526 return (p->sf.swapped); 527 } 528 529 int 530 pcap_major_version(pcap_t *p) 531 { 532 return (p->sf.version_major); 533 } 534 535 int 536 pcap_minor_version(pcap_t *p) 537 { 538 return (p->sf.version_minor); 539 } 540 541 FILE * 542 pcap_file(pcap_t *p) 543 { 544 return (p->sf.rfile); 545 } 546 547 int 548 pcap_fileno(pcap_t *p) 549 { 550 #ifndef WIN32 551 return (p->fd); 552 #else 553 if (p->adapter != NULL) 554 return ((int)(DWORD)p->adapter->hFile); 555 else 556 return (-1); 557 #endif 558 } 559 560 #if !defined(WIN32) && !defined(MSDOS) 561 int 562 pcap_get_selectable_fd(pcap_t *p) 563 { 564 return (p->selectable_fd); 565 } 566 #endif 567 568 void 569 pcap_perror(pcap_t *p, char *prefix) 570 { 571 fprintf(stderr, "%s: %s\n", prefix, p->errbuf); 572 } 573 574 char * 575 pcap_geterr(pcap_t *p) 576 { 577 return (p->errbuf); 578 } 579 580 int 581 pcap_getnonblock(pcap_t *p, char *errbuf) 582 { 583 return p->getnonblock_op(p, errbuf); 584 } 585 586 /* 587 * Get the current non-blocking mode setting, under the assumption that 588 * it's just the standard POSIX non-blocking flag. 589 * 590 * We don't look at "p->nonblock", in case somebody tweaked the FD 591 * directly. 592 */ 593 #if !defined(WIN32) && !defined(MSDOS) 594 int 595 pcap_getnonblock_fd(pcap_t *p, char *errbuf) 596 { 597 int fdflags; 598 599 fdflags = fcntl(p->fd, F_GETFL, 0); 600 if (fdflags == -1) { 601 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", 602 pcap_strerror(errno)); 603 return (-1); 604 } 605 if (fdflags & O_NONBLOCK) 606 return (1); 607 else 608 return (0); 609 } 610 #endif 611 612 int 613 pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf) 614 { 615 return p->setnonblock_op(p, nonblock, errbuf); 616 } 617 618 #if !defined(WIN32) && !defined(MSDOS) 619 /* 620 * Set non-blocking mode, under the assumption that it's just the 621 * standard POSIX non-blocking flag. (This can be called by the 622 * per-platform non-blocking-mode routine if that routine also 623 * needs to do some additional work.) 624 */ 625 int 626 pcap_setnonblock_fd(pcap_t *p, int nonblock, char *errbuf) 627 { 628 int fdflags; 629 630 fdflags = fcntl(p->fd, F_GETFL, 0); 631 if (fdflags == -1) { 632 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", 633 pcap_strerror(errno)); 634 return (-1); 635 } 636 if (nonblock) 637 fdflags |= O_NONBLOCK; 638 else 639 fdflags &= ~O_NONBLOCK; 640 if (fcntl(p->fd, F_SETFL, fdflags) == -1) { 641 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_SETFL: %s", 642 pcap_strerror(errno)); 643 return (-1); 644 } 645 return (0); 646 } 647 #endif 648 649 #ifdef WIN32 650 /* 651 * Generate a string for the last Win32-specific error (i.e. an error generated when 652 * calling a Win32 API). 653 * For errors occurred during standard C calls, we still use pcap_strerror() 654 */ 655 char * 656 pcap_win32strerror(void) 657 { 658 DWORD error; 659 static char errbuf[PCAP_ERRBUF_SIZE+1]; 660 int errlen; 661 char *p; 662 663 error = GetLastError(); 664 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf, 665 PCAP_ERRBUF_SIZE, NULL); 666 667 /* 668 * "FormatMessage()" "helpfully" sticks CR/LF at the end of the 669 * message. Get rid of it. 670 */ 671 errlen = strlen(errbuf); 672 if (errlen >= 2) { 673 errbuf[errlen - 1] = '\0'; 674 errbuf[errlen - 2] = '\0'; 675 } 676 p = strchr(errbuf, '\0'); 677 snprintf (p, sizeof(errbuf)-(p-errbuf), " (%lu)", error); 678 return (errbuf); 679 } 680 #endif 681 682 /* 683 * Not all systems have strerror(). 684 */ 685 const char * 686 pcap_strerror(int errnum) 687 { 688 #ifdef HAVE_STRERROR 689 return (strerror(errnum)); 690 #else 691 extern int sys_nerr; 692 extern const char *const sys_errlist[]; 693 static char ebuf[20]; 694 695 if ((unsigned int)errnum < sys_nerr) 696 return ((char *)sys_errlist[errnum]); 697 (void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum); 698 return(ebuf); 699 #endif 700 } 701 702 int 703 pcap_setfilter(pcap_t *p, struct bpf_program *fp) 704 { 705 return p->setfilter_op(p, fp); 706 } 707 708 /* 709 * Set direction flag, which controls whether we accept only incoming 710 * packets, only outgoing packets, or both. 711 * Note that, depending on the platform, some or all direction arguments 712 * might not be supported. 713 */ 714 int 715 pcap_setdirection(pcap_t *p, pcap_direction_t d) 716 { 717 if (p->setdirection_op == NULL) { 718 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 719 "Setting direction is not implemented on this platform"); 720 return -1; 721 } else 722 return p->setdirection_op(p, d); 723 } 724 725 int 726 pcap_stats(pcap_t *p, struct pcap_stat *ps) 727 { 728 return p->stats_op(p, ps); 729 } 730 731 static int 732 pcap_stats_dead(pcap_t *p, struct pcap_stat *ps _U_) 733 { 734 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 735 "Statistics aren't available from a pcap_open_dead pcap_t"); 736 return (-1); 737 } 738 739 void 740 pcap_close_common(pcap_t *p) 741 { 742 #ifdef BIOCSETBUFMODE 743 /* 744 * Check to see if this pcap instance was using the zerocopy buffer 745 * mode. If it was, delete the mappings. Note that p->buffer 746 * gets initialized to one of the mmaped regions in this case, so 747 * do not try and free it directly. 748 * 749 * If the regular buffer mode was selected, then it is safe to free 750 * this memory. 751 */ 752 if (p->zerocopy) { 753 if (p->zbuf1 != MAP_FAILED && p->zbuf1 != NULL) 754 munmap(p->zbuf1, p->zbufsize); 755 if (p->zbuf2 != MAP_FAILED && p->zbuf2 != NULL) 756 munmap(p->zbuf2, p->zbufsize); 757 p->buffer = NULL; 758 } else 759 #endif 760 if (p->buffer != NULL) 761 free(p->buffer); 762 #if !defined(WIN32) && !defined(MSDOS) 763 if (p->fd >= 0) 764 close(p->fd); 765 #endif 766 } 767 768 static void 769 pcap_close_dead(pcap_t *p _U_) 770 { 771 /* Nothing to do. */ 772 } 773 774 pcap_t * 775 pcap_open_dead(int linktype, int snaplen) 776 { 777 pcap_t *p; 778 779 p = malloc(sizeof(*p)); 780 if (p == NULL) 781 return NULL; 782 memset (p, 0, sizeof(*p)); 783 p->snapshot = snaplen; 784 p->linktype = linktype; 785 p->stats_op = pcap_stats_dead; 786 p->close_op = pcap_close_dead; 787 return p; 788 } 789 790 /* 791 * API compatible with WinPcap's "send a packet" routine - returns -1 792 * on error, 0 otherwise. 793 * 794 * XXX - what if we get a short write? 795 */ 796 int 797 pcap_sendpacket(pcap_t *p, const u_char *buf, int size) 798 { 799 if (p->inject_op(p, buf, size) == -1) 800 return (-1); 801 return (0); 802 } 803 804 /* 805 * API compatible with OpenBSD's "send a packet" routine - returns -1 on 806 * error, number of bytes written otherwise. 807 */ 808 int 809 pcap_inject(pcap_t *p, const void *buf, size_t size) 810 { 811 return (p->inject_op(p, buf, size)); 812 } 813 814 void 815 pcap_close(pcap_t *p) 816 { 817 p->close_op(p); 818 if (p->dlt_list != NULL) 819 free(p->dlt_list); 820 pcap_freecode(&p->fcode); 821 free(p); 822 } 823 824 /* 825 * We make the version string static, and return a pointer to it, rather 826 * than exporting the version string directly. On at least some UNIXes, 827 * if you import data from a shared library into an program, the data is 828 * bound into the program binary, so if the string in the version of the 829 * library with which the program was linked isn't the same as the 830 * string in the version of the library with which the program is being 831 * run, various undesirable things may happen (warnings, the string 832 * being the one from the version of the library with which the program 833 * was linked, or even weirder things, such as the string being the one 834 * from the library but being truncated). 835 */ 836 #ifdef HAVE_VERSION_H 837 #include "version.h" 838 #else 839 static const char pcap_version_string[] = "libpcap version 0.9.8"; 840 #endif 841 842 #ifdef WIN32 843 /* 844 * XXX - it'd be nice if we could somehow generate the WinPcap and libpcap 845 * version numbers when building WinPcap. (It'd be nice to do so for 846 * the packet.dll version number as well.) 847 */ 848 static const char wpcap_version_string[] = "4.0"; 849 static const char pcap_version_string_fmt[] = 850 "WinPcap version %s, based on %s"; 851 static const char pcap_version_string_packet_dll_fmt[] = 852 "WinPcap version %s (packet.dll version %s), based on %s"; 853 static char *full_pcap_version_string; 854 855 const char * 856 pcap_lib_version(void) 857 { 858 char *packet_version_string; 859 size_t full_pcap_version_string_len; 860 861 if (full_pcap_version_string == NULL) { 862 /* 863 * Generate the version string. 864 */ 865 packet_version_string = PacketGetVersion(); 866 if (strcmp(wpcap_version_string, packet_version_string) == 0) { 867 /* 868 * WinPcap version string and packet.dll version 869 * string are the same; just report the WinPcap 870 * version. 871 */ 872 full_pcap_version_string_len = 873 (sizeof pcap_version_string_fmt - 4) + 874 strlen(wpcap_version_string) + 875 strlen(pcap_version_string); 876 full_pcap_version_string = 877 malloc(full_pcap_version_string_len); 878 sprintf(full_pcap_version_string, 879 pcap_version_string_fmt, wpcap_version_string, 880 pcap_version_string); 881 } else { 882 /* 883 * WinPcap version string and packet.dll version 884 * string are different; that shouldn't be the 885 * case (the two libraries should come from the 886 * same version of WinPcap), so we report both 887 * versions. 888 */ 889 full_pcap_version_string_len = 890 (sizeof pcap_version_string_packet_dll_fmt - 6) + 891 strlen(wpcap_version_string) + 892 strlen(packet_version_string) + 893 strlen(pcap_version_string); 894 full_pcap_version_string = malloc(full_pcap_version_string_len); 895 896 sprintf(full_pcap_version_string, 897 pcap_version_string_packet_dll_fmt, 898 wpcap_version_string, packet_version_string, 899 pcap_version_string); 900 } 901 } 902 return (full_pcap_version_string); 903 } 904 905 #elif defined(MSDOS) 906 907 static char *full_pcap_version_string; 908 909 const char * 910 pcap_lib_version (void) 911 { 912 char *packet_version_string; 913 size_t full_pcap_version_string_len; 914 static char dospfx[] = "DOS-"; 915 916 if (full_pcap_version_string == NULL) { 917 /* 918 * Generate the version string. 919 */ 920 full_pcap_version_string_len = 921 sizeof dospfx + strlen(pcap_version_string); 922 full_pcap_version_string = 923 malloc(full_pcap_version_string_len); 924 strcpy(full_pcap_version_string, dospfx); 925 strcat(full_pcap_version_string, pcap_version_string); 926 } 927 return (full_pcap_version_string); 928 } 929 930 #else /* UN*X */ 931 932 const char * 933 pcap_lib_version(void) 934 { 935 return (pcap_version_string); 936 } 937 #endif 938