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 1.88.2.3 2005/05/27 23:33:00 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 #endif /* WIN32 */ 48 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <string.h> 52 #if !defined(_MSC_VER) && !defined(__BORLANDC__) 53 #include <unistd.h> 54 #endif 55 #include <fcntl.h> 56 #include <errno.h> 57 58 #ifdef HAVE_OS_PROTO_H 59 #include "os-proto.h" 60 #endif 61 62 #ifdef MSDOS 63 #include "pcap-dos.h" 64 #endif 65 66 #include "pcap-int.h" 67 68 #ifdef HAVE_DAG_API 69 #include <dagnew.h> 70 #include <dagapi.h> 71 #endif 72 73 int 74 pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 75 { 76 77 return p->read_op(p, cnt, callback, user); 78 } 79 80 /* 81 * XXX - is this necessary? 82 */ 83 int 84 pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 85 { 86 87 return p->read_op(p, cnt, callback, user); 88 } 89 90 int 91 pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 92 { 93 register int n; 94 95 for (;;) { 96 if (p->sf.rfile != NULL) { 97 /* 98 * 0 means EOF, so don't loop if we get 0. 99 */ 100 n = pcap_offline_read(p, cnt, callback, user); 101 } else { 102 /* 103 * XXX keep reading until we get something 104 * (or an error occurs) 105 */ 106 do { 107 n = p->read_op(p, cnt, callback, user); 108 } while (n == 0); 109 } 110 if (n <= 0) 111 return (n); 112 if (cnt > 0) { 113 cnt -= n; 114 if (cnt <= 0) 115 return (0); 116 } 117 } 118 } 119 120 struct singleton { 121 struct pcap_pkthdr *hdr; 122 const u_char *pkt; 123 }; 124 125 126 static void 127 pcap_oneshot(u_char *userData, const struct pcap_pkthdr *h, const u_char *pkt) 128 { 129 struct singleton *sp = (struct singleton *)userData; 130 *sp->hdr = *h; 131 sp->pkt = pkt; 132 } 133 134 const u_char * 135 pcap_next(pcap_t *p, struct pcap_pkthdr *h) 136 { 137 struct singleton s; 138 139 s.hdr = h; 140 if (pcap_dispatch(p, 1, pcap_oneshot, (u_char*)&s) <= 0) 141 return (0); 142 return (s.pkt); 143 } 144 145 struct pkt_for_fakecallback { 146 struct pcap_pkthdr *hdr; 147 const u_char **pkt; 148 }; 149 150 static void 151 pcap_fakecallback(u_char *userData, const struct pcap_pkthdr *h, 152 const u_char *pkt) 153 { 154 struct pkt_for_fakecallback *sp = (struct pkt_for_fakecallback *)userData; 155 156 *sp->hdr = *h; 157 *sp->pkt = pkt; 158 } 159 160 int 161 pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header, 162 const u_char **pkt_data) 163 { 164 struct pkt_for_fakecallback s; 165 166 s.hdr = &p->pcap_header; 167 s.pkt = pkt_data; 168 169 /* Saves a pointer to the packet headers */ 170 *pkt_header= &p->pcap_header; 171 172 if (p->sf.rfile != NULL) { 173 int status; 174 175 /* We are on an offline capture */ 176 status = pcap_offline_read(p, 1, pcap_fakecallback, 177 (u_char *)&s); 178 179 /* 180 * Return codes for pcap_offline_read() are: 181 * - 0: EOF 182 * - -1: error 183 * - >1: OK 184 * The first one ('0') conflicts with the return code of 185 * 0 from pcap_read() meaning "no packets arrived before 186 * the timeout expired", so we map it to -2 so you can 187 * distinguish between an EOF from a savefile and a 188 * "no packets arrived before the timeout expired, try 189 * again" from a live capture. 190 */ 191 if (status == 0) 192 return (-2); 193 else 194 return (status); 195 } 196 197 /* 198 * Return codes for pcap_read() are: 199 * - 0: timeout 200 * - -1: error 201 * - -2: loop was broken out of with pcap_breakloop() 202 * - >1: OK 203 * The first one ('0') conflicts with the return code of 0 from 204 * pcap_offline_read() meaning "end of file". 205 */ 206 return (p->read_op(p, 1, pcap_fakecallback, (u_char *)&s)); 207 } 208 209 /* 210 * Force the loop in "pcap_read()" or "pcap_read_offline()" to terminate. 211 */ 212 void 213 pcap_breakloop(pcap_t *p) 214 { 215 p->break_loop = 1; 216 } 217 218 int 219 pcap_datalink(pcap_t *p) 220 { 221 return (p->linktype); 222 } 223 224 int 225 pcap_list_datalinks(pcap_t *p, int **dlt_buffer) 226 { 227 if (p->dlt_count == 0) { 228 /* 229 * We couldn't fetch the list of DLTs, which means 230 * this platform doesn't support changing the 231 * DLT for an interface. Return a list of DLTs 232 * containing only the DLT this device supports. 233 */ 234 *dlt_buffer = (int*)malloc(sizeof(**dlt_buffer)); 235 if (*dlt_buffer == NULL) { 236 (void)snprintf(p->errbuf, sizeof(p->errbuf), 237 "malloc: %s", pcap_strerror(errno)); 238 return (-1); 239 } 240 **dlt_buffer = p->linktype; 241 return (1); 242 } else { 243 *dlt_buffer = (int*)malloc(sizeof(**dlt_buffer) * p->dlt_count); 244 if (*dlt_buffer == NULL) { 245 (void)snprintf(p->errbuf, sizeof(p->errbuf), 246 "malloc: %s", pcap_strerror(errno)); 247 return (-1); 248 } 249 (void)memcpy(*dlt_buffer, p->dlt_list, 250 sizeof(**dlt_buffer) * p->dlt_count); 251 return (p->dlt_count); 252 } 253 } 254 255 int 256 pcap_set_datalink(pcap_t *p, int dlt) 257 { 258 int i; 259 const char *dlt_name; 260 261 if (p->dlt_count == 0 || p->set_datalink_op == NULL) { 262 /* 263 * We couldn't fetch the list of DLTs, or we don't 264 * have a "set datalink" operation, which means 265 * this platform doesn't support changing the 266 * DLT for an interface. Check whether the new 267 * DLT is the one this interface supports. 268 */ 269 if (p->linktype != dlt) 270 goto unsupported; 271 272 /* 273 * It is, so there's nothing we need to do here. 274 */ 275 return (0); 276 } 277 for (i = 0; i < p->dlt_count; i++) 278 if (p->dlt_list[i] == dlt) 279 break; 280 if (i >= p->dlt_count) 281 goto unsupported; 282 if (p->dlt_count == 2 && p->dlt_list[0] == DLT_EN10MB && 283 dlt == DLT_DOCSIS) { 284 /* 285 * This is presumably an Ethernet device, as the first 286 * link-layer type it offers is DLT_EN10MB, and the only 287 * other type it offers is DLT_DOCSIS. That means that 288 * we can't tell the driver to supply DOCSIS link-layer 289 * headers - we're just pretending that's what we're 290 * getting, as, presumably, we're capturing on a dedicated 291 * link to a Cisco Cable Modem Termination System, and 292 * it's putting raw DOCSIS frames on the wire inside low-level 293 * Ethernet framing. 294 */ 295 p->linktype = dlt; 296 return (0); 297 } 298 if (p->set_datalink_op(p, dlt) == -1) 299 return (-1); 300 p->linktype = dlt; 301 return (0); 302 303 unsupported: 304 dlt_name = pcap_datalink_val_to_name(dlt); 305 if (dlt_name != NULL) { 306 (void) snprintf(p->errbuf, sizeof(p->errbuf), 307 "%s is not one of the DLTs supported by this device", 308 dlt_name); 309 } else { 310 (void) snprintf(p->errbuf, sizeof(p->errbuf), 311 "DLT %d is not one of the DLTs supported by this device", 312 dlt); 313 } 314 return (-1); 315 } 316 317 struct dlt_choice { 318 const char *name; 319 const char *description; 320 int dlt; 321 }; 322 323 #define DLT_CHOICE(code, description) { #code, description, code } 324 #define DLT_CHOICE_SENTINEL { NULL, NULL, 0 } 325 326 static struct dlt_choice dlt_choices[] = { 327 DLT_CHOICE(DLT_NULL, "BSD loopback"), 328 DLT_CHOICE(DLT_EN10MB, "Ethernet"), 329 DLT_CHOICE(DLT_IEEE802, "Token ring"), 330 DLT_CHOICE(DLT_ARCNET, "ARCNET"), 331 DLT_CHOICE(DLT_SLIP, "SLIP"), 332 DLT_CHOICE(DLT_PPP, "PPP"), 333 DLT_CHOICE(DLT_FDDI, "FDDI"), 334 DLT_CHOICE(DLT_ATM_RFC1483, "RFC 1483 LLC-encapsulated ATM"), 335 DLT_CHOICE(DLT_RAW, "Raw IP"), 336 DLT_CHOICE(DLT_SLIP_BSDOS, "BSD/OS SLIP"), 337 DLT_CHOICE(DLT_PPP_BSDOS, "BSD/OS PPP"), 338 DLT_CHOICE(DLT_ATM_CLIP, "Linux Classical IP-over-ATM"), 339 DLT_CHOICE(DLT_PPP_SERIAL, "PPP over serial"), 340 DLT_CHOICE(DLT_PPP_ETHER, "PPPoE"), 341 DLT_CHOICE(DLT_C_HDLC, "Cisco HDLC"), 342 DLT_CHOICE(DLT_IEEE802_11, "802.11"), 343 DLT_CHOICE(DLT_FRELAY, "Frame Relay"), 344 DLT_CHOICE(DLT_LOOP, "OpenBSD loopback"), 345 DLT_CHOICE(DLT_ENC, "OpenBSD encapsulated IP"), 346 DLT_CHOICE(DLT_LINUX_SLL, "Linux cooked"), 347 DLT_CHOICE(DLT_LTALK, "Localtalk"), 348 DLT_CHOICE(DLT_PFLOG, "OpenBSD pflog file"), 349 DLT_CHOICE(DLT_PRISM_HEADER, "802.11 plus Prism header"), 350 DLT_CHOICE(DLT_IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"), 351 DLT_CHOICE(DLT_SUNATM, "Sun raw ATM"), 352 DLT_CHOICE(DLT_IEEE802_11_RADIO, "802.11 plus BSD radio information header"), 353 DLT_CHOICE(DLT_APPLE_IP_OVER_IEEE1394, "Apple IP-over-IEEE 1394"), 354 DLT_CHOICE(DLT_ARCNET_LINUX, "Linux ARCNET"), 355 DLT_CHOICE(DLT_DOCSIS, "DOCSIS"), 356 DLT_CHOICE(DLT_LINUX_IRDA, "Linux IrDA"), 357 DLT_CHOICE(DLT_IEEE802_11_RADIO_AVS, "802.11 plus AVS radio information header"), 358 DLT_CHOICE(DLT_SYMANTEC_FIREWALL, "Symantec Firewall"), 359 DLT_CHOICE(DLT_JUNIPER_ATM1, "Juniper ATM1 PIC"), 360 DLT_CHOICE(DLT_JUNIPER_ATM2, "Juniper ATM2 PIC"), 361 DLT_CHOICE(DLT_JUNIPER_MLPPP, "Juniper Multi-Link PPP"), 362 DLT_CHOICE(DLT_PPP_PPPD, "PPP for pppd, with direction flag"), 363 DLT_CHOICE(DLT_JUNIPER_PPPOE, "Juniper PPPoE"), 364 DLT_CHOICE(DLT_JUNIPER_PPPOE_ATM, "Juniper PPPoE/ATM"), 365 DLT_CHOICE(DLT_GPRS_LLC, "GPRS LLC"), 366 DLT_CHOICE(DLT_GPF_T, "GPF-T"), 367 DLT_CHOICE(DLT_GPF_F, "GPF-F"), 368 DLT_CHOICE(DLT_JUNIPER_PIC_PEER, "Juniper PIC Peer"), 369 DLT_CHOICE(DLT_JUNIPER_MLFR, "Juniper Multi-Link Frame Relay"), 370 DLT_CHOICE(DLT_ERF_ETH, "Ethernet with Endace ERF header"), 371 DLT_CHOICE(DLT_ERF_POS, "Packet-over-SONET with Endace ERF header"), 372 DLT_CHOICE(DLT_JUNIPER_GGSN, "Juniper GGSN PIC"), 373 DLT_CHOICE(DLT_JUNIPER_ES, "Juniper Encryption Services PIC"), 374 DLT_CHOICE(DLT_JUNIPER_MONITOR, "Juniper Passive Monitor PIC"), 375 DLT_CHOICE(DLT_JUNIPER_SERVICES, "Juniper Advanced Services PIC"), 376 DLT_CHOICE_SENTINEL 377 }; 378 379 /* 380 * This array is designed for mapping upper and lower case letter 381 * together for a case independent comparison. The mappings are 382 * based upon ascii character sequences. 383 */ 384 static const u_char charmap[] = { 385 (u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003', 386 (u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007', 387 (u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013', 388 (u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017', 389 (u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023', 390 (u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027', 391 (u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033', 392 (u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037', 393 (u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043', 394 (u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047', 395 (u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053', 396 (u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057', 397 (u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063', 398 (u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067', 399 (u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073', 400 (u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077', 401 (u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143', 402 (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147', 403 (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153', 404 (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157', 405 (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163', 406 (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167', 407 (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133', 408 (u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137', 409 (u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143', 410 (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147', 411 (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153', 412 (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157', 413 (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163', 414 (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167', 415 (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173', 416 (u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177', 417 (u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203', 418 (u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207', 419 (u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213', 420 (u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217', 421 (u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223', 422 (u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227', 423 (u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233', 424 (u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237', 425 (u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243', 426 (u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247', 427 (u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253', 428 (u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257', 429 (u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263', 430 (u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267', 431 (u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273', 432 (u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277', 433 (u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343', 434 (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347', 435 (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353', 436 (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357', 437 (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363', 438 (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367', 439 (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333', 440 (u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337', 441 (u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343', 442 (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347', 443 (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353', 444 (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357', 445 (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363', 446 (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367', 447 (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373', 448 (u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377', 449 }; 450 451 int 452 pcap_strcasecmp(const char *s1, const char *s2) 453 { 454 register const u_char *cm = charmap, 455 *us1 = (u_char *)s1, 456 *us2 = (u_char *)s2; 457 458 while (cm[*us1] == cm[*us2++]) 459 if (*us1++ == '\0') 460 return(0); 461 return (cm[*us1] - cm[*--us2]); 462 } 463 464 int 465 pcap_datalink_name_to_val(const char *name) 466 { 467 int i; 468 469 for (i = 0; dlt_choices[i].name != NULL; i++) { 470 if (pcap_strcasecmp(dlt_choices[i].name + sizeof("DLT_") - 1, 471 name) == 0) 472 return (dlt_choices[i].dlt); 473 } 474 return (-1); 475 } 476 477 const char * 478 pcap_datalink_val_to_name(int dlt) 479 { 480 int i; 481 482 for (i = 0; dlt_choices[i].name != NULL; i++) { 483 if (dlt_choices[i].dlt == dlt) 484 return (dlt_choices[i].name + sizeof("DLT_") - 1); 485 } 486 return (NULL); 487 } 488 489 const char * 490 pcap_datalink_val_to_description(int dlt) 491 { 492 int i; 493 494 for (i = 0; dlt_choices[i].name != NULL; i++) { 495 if (dlt_choices[i].dlt == dlt) 496 return (dlt_choices[i].description); 497 } 498 return (NULL); 499 } 500 501 int 502 pcap_snapshot(pcap_t *p) 503 { 504 return (p->snapshot); 505 } 506 507 int 508 pcap_is_swapped(pcap_t *p) 509 { 510 return (p->sf.swapped); 511 } 512 513 int 514 pcap_major_version(pcap_t *p) 515 { 516 return (p->sf.version_major); 517 } 518 519 int 520 pcap_minor_version(pcap_t *p) 521 { 522 return (p->sf.version_minor); 523 } 524 525 FILE * 526 pcap_file(pcap_t *p) 527 { 528 return (p->sf.rfile); 529 } 530 531 int 532 pcap_fileno(pcap_t *p) 533 { 534 #ifndef WIN32 535 return (p->fd); 536 #else 537 if (p->adapter != NULL) 538 return ((int)(DWORD)p->adapter->hFile); 539 else 540 return (-1); 541 #endif 542 } 543 544 #if !defined(WIN32) && !defined(MSDOS) 545 int 546 pcap_get_selectable_fd(pcap_t *p) 547 { 548 return (p->selectable_fd); 549 } 550 #endif 551 552 void 553 pcap_perror(pcap_t *p, char *prefix) 554 { 555 fprintf(stderr, "%s: %s\n", prefix, p->errbuf); 556 } 557 558 char * 559 pcap_geterr(pcap_t *p) 560 { 561 return (p->errbuf); 562 } 563 564 int 565 pcap_getnonblock(pcap_t *p, char *errbuf) 566 { 567 return p->getnonblock_op(p, errbuf); 568 } 569 570 /* 571 * Get the current non-blocking mode setting, under the assumption that 572 * it's just the standard POSIX non-blocking flag. 573 * 574 * We don't look at "p->nonblock", in case somebody tweaked the FD 575 * directly. 576 */ 577 #if !defined(WIN32) && !defined(MSDOS) 578 int 579 pcap_getnonblock_fd(pcap_t *p, char *errbuf) 580 { 581 int fdflags; 582 583 fdflags = fcntl(p->fd, F_GETFL, 0); 584 if (fdflags == -1) { 585 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", 586 pcap_strerror(errno)); 587 return (-1); 588 } 589 if (fdflags & O_NONBLOCK) 590 return (1); 591 else 592 return (0); 593 } 594 #endif 595 596 int 597 pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf) 598 { 599 return p->setnonblock_op(p, nonblock, errbuf); 600 } 601 602 #if !defined(WIN32) && !defined(MSDOS) 603 /* 604 * Set non-blocking mode, under the assumption that it's just the 605 * standard POSIX non-blocking flag. (This can be called by the 606 * per-platform non-blocking-mode routine if that routine also 607 * needs to do some additional work.) 608 */ 609 int 610 pcap_setnonblock_fd(pcap_t *p, int nonblock, char *errbuf) 611 { 612 int fdflags; 613 614 fdflags = fcntl(p->fd, F_GETFL, 0); 615 if (fdflags == -1) { 616 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", 617 pcap_strerror(errno)); 618 return (-1); 619 } 620 if (nonblock) 621 fdflags |= O_NONBLOCK; 622 else 623 fdflags &= ~O_NONBLOCK; 624 if (fcntl(p->fd, F_SETFL, fdflags) == -1) { 625 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_SETFL: %s", 626 pcap_strerror(errno)); 627 return (-1); 628 } 629 return (0); 630 } 631 #endif 632 633 #ifdef WIN32 634 /* 635 * Generate a string for the last Win32-specific error (i.e. an error generated when 636 * calling a Win32 API). 637 * For errors occurred during standard C calls, we still use pcap_strerror() 638 */ 639 char * 640 pcap_win32strerror(void) 641 { 642 DWORD error; 643 static char errbuf[PCAP_ERRBUF_SIZE+1]; 644 int errlen; 645 char *p; 646 647 error = GetLastError(); 648 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf, 649 PCAP_ERRBUF_SIZE, NULL); 650 651 /* 652 * "FormatMessage()" "helpfully" sticks CR/LF at the end of the 653 * message. Get rid of it. 654 */ 655 errlen = strlen(errbuf); 656 if (errlen >= 2) { 657 errbuf[errlen - 1] = '\0'; 658 errbuf[errlen - 2] = '\0'; 659 } 660 p = strchr(errbuf, '\0'); 661 snprintf (p, sizeof(errbuf)-(p-errbuf), " (%lu)", error); 662 return (errbuf); 663 } 664 #endif 665 666 /* 667 * Not all systems have strerror(). 668 */ 669 char * 670 pcap_strerror(int errnum) 671 { 672 #ifdef HAVE_STRERROR 673 return (strerror(errnum)); 674 #else 675 extern int sys_nerr; 676 extern const char *const sys_errlist[]; 677 static char ebuf[20]; 678 679 if ((unsigned int)errnum < sys_nerr) 680 return ((char *)sys_errlist[errnum]); 681 (void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum); 682 return(ebuf); 683 #endif 684 } 685 686 int 687 pcap_setfilter(pcap_t *p, struct bpf_program *fp) 688 { 689 return p->setfilter_op(p, fp); 690 } 691 692 /* 693 * Set direction flag, which controls whether we accept only incoming 694 * packets, only outgoing packets, or both. 695 * Note that, depending on the platform, some or all direction arguments 696 * might not be supported. 697 */ 698 int 699 pcap_setdirection(pcap_t *p, direction_t d) 700 { 701 if (p->setdirection_op == NULL) { 702 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 703 "Setting direction is not implemented on this platform"); 704 return -1; 705 } else 706 return p->setdirection_op(p, d); 707 } 708 709 int 710 pcap_stats(pcap_t *p, struct pcap_stat *ps) 711 { 712 return p->stats_op(p, ps); 713 } 714 715 static int 716 pcap_stats_dead(pcap_t *p, struct pcap_stat *ps _U_) 717 { 718 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 719 "Statistics aren't available from a pcap_open_dead pcap_t"); 720 return (-1); 721 } 722 723 void 724 pcap_close_common(pcap_t *p) 725 { 726 if (p->buffer != NULL) 727 free(p->buffer); 728 #if !defined(WIN32) && !defined(MSDOS) 729 if (p->fd >= 0) 730 close(p->fd); 731 #endif 732 } 733 734 static void 735 pcap_close_dead(pcap_t *p _U_) 736 { 737 /* Nothing to do. */ 738 } 739 740 pcap_t * 741 pcap_open_dead(int linktype, int snaplen) 742 { 743 pcap_t *p; 744 745 p = malloc(sizeof(*p)); 746 if (p == NULL) 747 return NULL; 748 memset (p, 0, sizeof(*p)); 749 p->snapshot = snaplen; 750 p->linktype = linktype; 751 p->stats_op = pcap_stats_dead; 752 p->close_op = pcap_close_dead; 753 return p; 754 } 755 756 /* 757 * API compatible with WinPcap's "send a packet" routine - returns -1 758 * on error, 0 otherwise. 759 * 760 * XXX - what if we get a short write? 761 */ 762 int 763 pcap_sendpacket(pcap_t *p, const u_char *buf, int size) 764 { 765 if (p->inject_op(p, buf, size) == -1) 766 return (-1); 767 return (0); 768 } 769 770 /* 771 * API compatible with OpenBSD's "send a packet" routine - returns -1 on 772 * error, number of bytes written otherwise. 773 */ 774 int 775 pcap_inject(pcap_t *p, const void *buf, size_t size) 776 { 777 return (p->inject_op(p, buf, size)); 778 } 779 780 void 781 pcap_close(pcap_t *p) 782 { 783 p->close_op(p); 784 if (p->dlt_list != NULL) 785 free(p->dlt_list); 786 pcap_freecode(&p->fcode); 787 free(p); 788 } 789 790 /* 791 * We make the version string static, and return a pointer to it, rather 792 * than exporting the version string directly. On at least some UNIXes, 793 * if you import data from a shared library into an program, the data is 794 * bound into the program binary, so if the string in the version of the 795 * library with which the program was linked isn't the same as the 796 * string in the version of the library with which the program is being 797 * run, various undesirable things may happen (warnings, the string 798 * being the one from the version of the library with which the program 799 * was linked, or even weirder things, such as the string being the one 800 * from the library but being truncated). 801 */ 802 #ifdef HAVE_VERSION_H 803 #include "version.h" 804 #else 805 static const char pcap_version_string[] = "libpcap version 0.9[.x]"; 806 #endif 807 808 #ifdef WIN32 809 /* 810 * XXX - it'd be nice if we could somehow generate the WinPcap and libpcap 811 * version numbers when building WinPcap. (It'd be nice to do so for 812 * the packet.dll version number as well.) 813 */ 814 static const char wpcap_version_string[] = "3.1"; 815 static const char pcap_version_string_fmt[] = 816 "WinPcap version %s, based on %s"; 817 static const char pcap_version_string_packet_dll_fmt[] = 818 "WinPcap version %s (packet.dll version %s), based on %s"; 819 static char *full_pcap_version_string; 820 821 const char * 822 pcap_lib_version(void) 823 { 824 char *packet_version_string; 825 size_t full_pcap_version_string_len; 826 827 if (full_pcap_version_string == NULL) { 828 /* 829 * Generate the version string. 830 */ 831 packet_version_string = PacketGetVersion(); 832 if (strcmp(wpcap_version_string, packet_version_string) == 0) { 833 /* 834 * WinPcap version string and packet.dll version 835 * string are the same; just report the WinPcap 836 * version. 837 */ 838 full_pcap_version_string_len = 839 (sizeof pcap_version_string_fmt - 4) + 840 strlen(wpcap_version_string) + 841 strlen(pcap_version_string); 842 full_pcap_version_string = 843 malloc(full_pcap_version_string_len); 844 sprintf(full_pcap_version_string, 845 pcap_version_string_fmt, wpcap_version_string, 846 pcap_version_string); 847 } else { 848 /* 849 * WinPcap version string and packet.dll version 850 * string are different; that shouldn't be the 851 * case (the two libraries should come from the 852 * same version of WinPcap), so we report both 853 * versions. 854 */ 855 full_pcap_version_string_len = 856 (sizeof pcap_version_string_packet_dll_fmt - 6) + 857 strlen(wpcap_version_string) + 858 strlen(packet_version_string) + 859 strlen(pcap_version_string); 860 full_pcap_version_string = malloc(full_pcap_version_string_len); 861 862 sprintf(full_pcap_version_string, 863 pcap_version_string_packet_dll_fmt, 864 wpcap_version_string, packet_version_string, 865 pcap_version_string); 866 } 867 } 868 return (full_pcap_version_string); 869 } 870 871 #elif defined(MSDOS) 872 873 static char *full_pcap_version_string; 874 875 const char * 876 pcap_lib_version (void) 877 { 878 char *packet_version_string; 879 size_t full_pcap_version_string_len; 880 static char dospfx[] = "DOS-"; 881 882 if (full_pcap_version_string == NULL) { 883 /* 884 * Generate the version string. 885 */ 886 full_pcap_version_string_len = 887 sizeof dospfx + strlen(pcap_version_string); 888 full_pcap_version_string = 889 malloc(full_pcap_version_string_len); 890 strcpy(full_pcap_version_string, dospfx); 891 strcat(full_pcap_version_string, pcap_version_string); 892 } 893 return (full_pcap_version_string); 894 } 895 896 #else /* UN*X */ 897 898 const char * 899 pcap_lib_version(void) 900 { 901 return (pcap_version_string); 902 } 903 #endif 904