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 #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*)calloc(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_LINUX_LAPD, "Linux vISDN LAPD"), 358 DLT_CHOICE(DLT_IEEE802_11_RADIO_AVS, "802.11 plus AVS radio information header"), 359 DLT_CHOICE(DLT_SYMANTEC_FIREWALL, "Symantec Firewall"), 360 DLT_CHOICE(DLT_JUNIPER_ATM1, "Juniper ATM1 PIC"), 361 DLT_CHOICE(DLT_JUNIPER_ATM2, "Juniper ATM2 PIC"), 362 DLT_CHOICE(DLT_JUNIPER_MLPPP, "Juniper Multi-Link PPP"), 363 DLT_CHOICE(DLT_PPP_PPPD, "PPP for pppd, with direction flag"), 364 DLT_CHOICE(DLT_JUNIPER_PPPOE, "Juniper PPPoE"), 365 DLT_CHOICE(DLT_JUNIPER_PPPOE_ATM, "Juniper PPPoE/ATM"), 366 DLT_CHOICE(DLT_GPRS_LLC, "GPRS LLC"), 367 DLT_CHOICE(DLT_GPF_T, "GPF-T"), 368 DLT_CHOICE(DLT_GPF_F, "GPF-F"), 369 DLT_CHOICE(DLT_JUNIPER_PIC_PEER, "Juniper PIC Peer"), 370 DLT_CHOICE(DLT_JUNIPER_MLFR, "Juniper Multi-Link Frame Relay"), 371 DLT_CHOICE(DLT_ERF_ETH, "Ethernet with Endace ERF header"), 372 DLT_CHOICE(DLT_ERF_POS, "Packet-over-SONET with Endace ERF header"), 373 DLT_CHOICE(DLT_JUNIPER_GGSN, "Juniper GGSN PIC"), 374 DLT_CHOICE(DLT_JUNIPER_ES, "Juniper Encryption Services PIC"), 375 DLT_CHOICE(DLT_JUNIPER_MONITOR, "Juniper Passive Monitor PIC"), 376 DLT_CHOICE(DLT_JUNIPER_SERVICES, "Juniper Advanced Services PIC"), 377 DLT_CHOICE(DLT_JUNIPER_MFR, "Juniper FRF.16 Frame Relay"), 378 DLT_CHOICE(DLT_JUNIPER_ETHER, "Juniper Ethernet"), 379 DLT_CHOICE(DLT_JUNIPER_PPP, "Juniper PPP"), 380 DLT_CHOICE(DLT_JUNIPER_FRELAY, "Juniper Frame Relay"), 381 DLT_CHOICE(DLT_JUNIPER_CHDLC, "Juniper C-HDLC"), 382 DLT_CHOICE(DLT_MFR, "FRF.16 Frame Relay"), 383 DLT_CHOICE(DLT_JUNIPER_VP, "Juniper Voice PIC"), 384 DLT_CHOICE(DLT_MTP2, "SS7 MTP2"), 385 DLT_CHOICE(DLT_A429, "Arinc 429"), 386 DLT_CHOICE(DLT_A653_ICM, "Arinc 653 Interpartition Communication"), 387 DLT_CHOICE(DLT_USB, "USB"), 388 DLT_CHOICE(DLT_BLUETOOTH_HCI_H4, "Bluetooth HCI UART transport layer"), 389 DLT_CHOICE(DLT_CAN20B, "Controller Area Network (CAN) v. 2.0B"), 390 DLT_CHOICE(DLT_MTP2_WITH_PHDR, "SS7 MTP2 with Pseudo-header"), 391 DLT_CHOICE_SENTINEL 392 }; 393 394 /* 395 * This array is designed for mapping upper and lower case letter 396 * together for a case independent comparison. The mappings are 397 * based upon ascii character sequences. 398 */ 399 static const u_char charmap[] = { 400 (u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003', 401 (u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007', 402 (u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013', 403 (u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017', 404 (u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023', 405 (u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027', 406 (u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033', 407 (u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037', 408 (u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043', 409 (u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047', 410 (u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053', 411 (u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057', 412 (u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063', 413 (u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067', 414 (u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073', 415 (u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077', 416 (u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143', 417 (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147', 418 (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153', 419 (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157', 420 (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163', 421 (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167', 422 (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133', 423 (u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137', 424 (u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143', 425 (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147', 426 (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153', 427 (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157', 428 (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163', 429 (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167', 430 (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173', 431 (u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177', 432 (u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203', 433 (u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207', 434 (u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213', 435 (u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217', 436 (u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223', 437 (u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227', 438 (u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233', 439 (u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237', 440 (u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243', 441 (u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247', 442 (u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253', 443 (u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257', 444 (u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263', 445 (u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267', 446 (u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273', 447 (u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277', 448 (u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343', 449 (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347', 450 (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353', 451 (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357', 452 (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363', 453 (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367', 454 (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333', 455 (u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337', 456 (u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343', 457 (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347', 458 (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353', 459 (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357', 460 (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363', 461 (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367', 462 (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373', 463 (u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377', 464 }; 465 466 int 467 pcap_strcasecmp(const char *s1, const char *s2) 468 { 469 register const u_char *cm = charmap, 470 *us1 = (const u_char *)s1, 471 *us2 = (const u_char *)s2; 472 473 while (cm[*us1] == cm[*us2++]) 474 if (*us1++ == '\0') 475 return(0); 476 return (cm[*us1] - cm[*--us2]); 477 } 478 479 int 480 pcap_datalink_name_to_val(const char *name) 481 { 482 int i; 483 484 for (i = 0; dlt_choices[i].name != NULL; i++) { 485 if (pcap_strcasecmp(dlt_choices[i].name + sizeof("DLT_") - 1, 486 name) == 0) 487 return (dlt_choices[i].dlt); 488 } 489 return (-1); 490 } 491 492 const char * 493 pcap_datalink_val_to_name(int dlt) 494 { 495 int i; 496 497 for (i = 0; dlt_choices[i].name != NULL; i++) { 498 if (dlt_choices[i].dlt == dlt) 499 return (dlt_choices[i].name + sizeof("DLT_") - 1); 500 } 501 return (NULL); 502 } 503 504 const char * 505 pcap_datalink_val_to_description(int dlt) 506 { 507 int i; 508 509 for (i = 0; dlt_choices[i].name != NULL; i++) { 510 if (dlt_choices[i].dlt == dlt) 511 return (dlt_choices[i].description); 512 } 513 return (NULL); 514 } 515 516 int 517 pcap_snapshot(pcap_t *p) 518 { 519 return (p->snapshot); 520 } 521 522 int 523 pcap_is_swapped(pcap_t *p) 524 { 525 return (p->sf.swapped); 526 } 527 528 int 529 pcap_major_version(pcap_t *p) 530 { 531 return (p->sf.version_major); 532 } 533 534 int 535 pcap_minor_version(pcap_t *p) 536 { 537 return (p->sf.version_minor); 538 } 539 540 FILE * 541 pcap_file(pcap_t *p) 542 { 543 return (p->sf.rfile); 544 } 545 546 int 547 pcap_fileno(pcap_t *p) 548 { 549 #ifndef WIN32 550 return (p->fd); 551 #else 552 if (p->adapter != NULL) 553 return ((int)(DWORD)p->adapter->hFile); 554 else 555 return (-1); 556 #endif 557 } 558 559 #if !defined(WIN32) && !defined(MSDOS) 560 int 561 pcap_get_selectable_fd(pcap_t *p) 562 { 563 return (p->selectable_fd); 564 } 565 #endif 566 567 void 568 pcap_perror(pcap_t *p, char *prefix) 569 { 570 fprintf(stderr, "%s: %s\n", prefix, p->errbuf); 571 } 572 573 char * 574 pcap_geterr(pcap_t *p) 575 { 576 return (p->errbuf); 577 } 578 579 int 580 pcap_getnonblock(pcap_t *p, char *errbuf) 581 { 582 return p->getnonblock_op(p, errbuf); 583 } 584 585 /* 586 * Get the current non-blocking mode setting, under the assumption that 587 * it's just the standard POSIX non-blocking flag. 588 * 589 * We don't look at "p->nonblock", in case somebody tweaked the FD 590 * directly. 591 */ 592 #if !defined(WIN32) && !defined(MSDOS) 593 int 594 pcap_getnonblock_fd(pcap_t *p, char *errbuf) 595 { 596 int fdflags; 597 598 fdflags = fcntl(p->fd, F_GETFL, 0); 599 if (fdflags == -1) { 600 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", 601 pcap_strerror(errno)); 602 return (-1); 603 } 604 if (fdflags & O_NONBLOCK) 605 return (1); 606 else 607 return (0); 608 } 609 #endif 610 611 int 612 pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf) 613 { 614 return p->setnonblock_op(p, nonblock, errbuf); 615 } 616 617 #if !defined(WIN32) && !defined(MSDOS) 618 /* 619 * Set non-blocking mode, under the assumption that it's just the 620 * standard POSIX non-blocking flag. (This can be called by the 621 * per-platform non-blocking-mode routine if that routine also 622 * needs to do some additional work.) 623 */ 624 int 625 pcap_setnonblock_fd(pcap_t *p, int nonblock, char *errbuf) 626 { 627 int fdflags; 628 629 fdflags = fcntl(p->fd, F_GETFL, 0); 630 if (fdflags == -1) { 631 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s", 632 pcap_strerror(errno)); 633 return (-1); 634 } 635 if (nonblock) 636 fdflags |= O_NONBLOCK; 637 else 638 fdflags &= ~O_NONBLOCK; 639 if (fcntl(p->fd, F_SETFL, fdflags) == -1) { 640 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_SETFL: %s", 641 pcap_strerror(errno)); 642 return (-1); 643 } 644 return (0); 645 } 646 #endif 647 648 #ifdef WIN32 649 /* 650 * Generate a string for the last Win32-specific error (i.e. an error generated when 651 * calling a Win32 API). 652 * For errors occurred during standard C calls, we still use pcap_strerror() 653 */ 654 char * 655 pcap_win32strerror(void) 656 { 657 DWORD error; 658 static char errbuf[PCAP_ERRBUF_SIZE+1]; 659 int errlen; 660 char *p; 661 662 error = GetLastError(); 663 FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf, 664 PCAP_ERRBUF_SIZE, NULL); 665 666 /* 667 * "FormatMessage()" "helpfully" sticks CR/LF at the end of the 668 * message. Get rid of it. 669 */ 670 errlen = strlen(errbuf); 671 if (errlen >= 2) { 672 errbuf[errlen - 1] = '\0'; 673 errbuf[errlen - 2] = '\0'; 674 } 675 p = strchr(errbuf, '\0'); 676 snprintf (p, sizeof(errbuf)-(p-errbuf), " (%lu)", error); 677 return (errbuf); 678 } 679 #endif 680 681 /* 682 * Not all systems have strerror(). 683 */ 684 const char * 685 pcap_strerror(int errnum) 686 { 687 #ifdef HAVE_STRERROR 688 return (strerror(errnum)); 689 #else 690 extern int sys_nerr; 691 extern const char *const sys_errlist[]; 692 static char ebuf[20]; 693 694 if ((unsigned int)errnum < sys_nerr) 695 return ((char *)sys_errlist[errnum]); 696 (void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum); 697 return(ebuf); 698 #endif 699 } 700 701 int 702 pcap_setfilter(pcap_t *p, struct bpf_program *fp) 703 { 704 return p->setfilter_op(p, fp); 705 } 706 707 /* 708 * Set direction flag, which controls whether we accept only incoming 709 * packets, only outgoing packets, or both. 710 * Note that, depending on the platform, some or all direction arguments 711 * might not be supported. 712 */ 713 int 714 pcap_setdirection(pcap_t *p, pcap_direction_t d) 715 { 716 if (p->setdirection_op == NULL) { 717 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 718 "Setting direction is not implemented on this platform"); 719 return -1; 720 } else 721 return p->setdirection_op(p, d); 722 } 723 724 int 725 pcap_stats(pcap_t *p, struct pcap_stat *ps) 726 { 727 return p->stats_op(p, ps); 728 } 729 730 static int 731 pcap_stats_dead(pcap_t *p, struct pcap_stat *ps _U_) 732 { 733 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 734 "Statistics aren't available from a pcap_open_dead pcap_t"); 735 return (-1); 736 } 737 738 void 739 pcap_close_common(pcap_t *p) 740 { 741 if (p->buffer != NULL) 742 free(p->buffer); 743 #if !defined(WIN32) && !defined(MSDOS) 744 if (p->fd >= 0) 745 close(p->fd); 746 #endif 747 } 748 749 static void 750 pcap_close_dead(pcap_t *p _U_) 751 { 752 /* Nothing to do. */ 753 } 754 755 pcap_t * 756 pcap_open_dead(int linktype, int snaplen) 757 { 758 pcap_t *p; 759 760 p = malloc(sizeof(*p)); 761 if (p == NULL) 762 return NULL; 763 memset (p, 0, sizeof(*p)); 764 p->snapshot = snaplen; 765 p->linktype = linktype; 766 p->stats_op = pcap_stats_dead; 767 p->close_op = pcap_close_dead; 768 return p; 769 } 770 771 /* 772 * API compatible with WinPcap's "send a packet" routine - returns -1 773 * on error, 0 otherwise. 774 * 775 * XXX - what if we get a short write? 776 */ 777 int 778 pcap_sendpacket(pcap_t *p, const u_char *buf, int size) 779 { 780 if (p->inject_op(p, buf, size) == -1) 781 return (-1); 782 return (0); 783 } 784 785 /* 786 * API compatible with OpenBSD's "send a packet" routine - returns -1 on 787 * error, number of bytes written otherwise. 788 */ 789 int 790 pcap_inject(pcap_t *p, const void *buf, size_t size) 791 { 792 return (p->inject_op(p, buf, size)); 793 } 794 795 void 796 pcap_close(pcap_t *p) 797 { 798 p->close_op(p); 799 if (p->dlt_list != NULL) 800 free(p->dlt_list); 801 pcap_freecode(&p->fcode); 802 free(p); 803 } 804 805 /* 806 * We make the version string static, and return a pointer to it, rather 807 * than exporting the version string directly. On at least some UNIXes, 808 * if you import data from a shared library into an program, the data is 809 * bound into the program binary, so if the string in the version of the 810 * library with which the program was linked isn't the same as the 811 * string in the version of the library with which the program is being 812 * run, various undesirable things may happen (warnings, the string 813 * being the one from the version of the library with which the program 814 * was linked, or even weirder things, such as the string being the one 815 * from the library but being truncated). 816 */ 817 #ifdef HAVE_VERSION_H 818 #include "version.h" 819 #else 820 static const char pcap_version_string[] = "libpcap version 0.9.8"; 821 #endif 822 823 #ifdef WIN32 824 /* 825 * XXX - it'd be nice if we could somehow generate the WinPcap and libpcap 826 * version numbers when building WinPcap. (It'd be nice to do so for 827 * the packet.dll version number as well.) 828 */ 829 static const char wpcap_version_string[] = "4.0"; 830 static const char pcap_version_string_fmt[] = 831 "WinPcap version %s, based on %s"; 832 static const char pcap_version_string_packet_dll_fmt[] = 833 "WinPcap version %s (packet.dll version %s), based on %s"; 834 static char *full_pcap_version_string; 835 836 const char * 837 pcap_lib_version(void) 838 { 839 char *packet_version_string; 840 size_t full_pcap_version_string_len; 841 842 if (full_pcap_version_string == NULL) { 843 /* 844 * Generate the version string. 845 */ 846 packet_version_string = PacketGetVersion(); 847 if (strcmp(wpcap_version_string, packet_version_string) == 0) { 848 /* 849 * WinPcap version string and packet.dll version 850 * string are the same; just report the WinPcap 851 * version. 852 */ 853 full_pcap_version_string_len = 854 (sizeof pcap_version_string_fmt - 4) + 855 strlen(wpcap_version_string) + 856 strlen(pcap_version_string); 857 full_pcap_version_string = 858 malloc(full_pcap_version_string_len); 859 sprintf(full_pcap_version_string, 860 pcap_version_string_fmt, wpcap_version_string, 861 pcap_version_string); 862 } else { 863 /* 864 * WinPcap version string and packet.dll version 865 * string are different; that shouldn't be the 866 * case (the two libraries should come from the 867 * same version of WinPcap), so we report both 868 * versions. 869 */ 870 full_pcap_version_string_len = 871 (sizeof pcap_version_string_packet_dll_fmt - 6) + 872 strlen(wpcap_version_string) + 873 strlen(packet_version_string) + 874 strlen(pcap_version_string); 875 full_pcap_version_string = malloc(full_pcap_version_string_len); 876 877 sprintf(full_pcap_version_string, 878 pcap_version_string_packet_dll_fmt, 879 wpcap_version_string, packet_version_string, 880 pcap_version_string); 881 } 882 } 883 return (full_pcap_version_string); 884 } 885 886 #elif defined(MSDOS) 887 888 static char *full_pcap_version_string; 889 890 const char * 891 pcap_lib_version (void) 892 { 893 char *packet_version_string; 894 size_t full_pcap_version_string_len; 895 static char dospfx[] = "DOS-"; 896 897 if (full_pcap_version_string == NULL) { 898 /* 899 * Generate the version string. 900 */ 901 full_pcap_version_string_len = 902 sizeof dospfx + strlen(pcap_version_string); 903 full_pcap_version_string = 904 malloc(full_pcap_version_string_len); 905 strcpy(full_pcap_version_string, dospfx); 906 strcat(full_pcap_version_string, pcap_version_string); 907 } 908 return (full_pcap_version_string); 909 } 910 911 #else /* UN*X */ 912 913 const char * 914 pcap_lib_version(void) 915 { 916 return (pcap_version_string); 917 } 918 #endif 919
