inet.c revision 214518
1/* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */ 2/* 3 * Copyright (c) 1994, 1995, 1996, 1997, 1998 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by the Computer Systems 17 * Engineering Group at Lawrence Berkeley Laboratory. 18 * 4. Neither the name of the University nor of the Laboratory may be used 19 * to endorse or promote products derived from this software without 20 * specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35#ifndef lint 36static const char rcsid[] _U_ = 37 "@(#) $Header: /tcpdump/master/libpcap/inet.c,v 1.79 2008-04-20 18:19:02 guy Exp $ (LBL)"; 38#endif 39 40#ifdef HAVE_CONFIG_H 41#include "config.h" 42#endif 43 44#ifdef WIN32 45#include <pcap-stdinc.h> 46#else /* WIN32 */ 47 48#include <sys/param.h> 49#ifndef MSDOS 50#include <sys/file.h> 51#endif 52#include <sys/ioctl.h> 53#include <sys/socket.h> 54#ifdef HAVE_SYS_SOCKIO_H 55#include <sys/sockio.h> 56#endif 57 58struct mbuf; /* Squelch compiler warnings on some platforms for */ 59struct rtentry; /* declarations in <net/if.h> */ 60#include <net/if.h> 61#include <netinet/in.h> 62#endif /* WIN32 */ 63 64#include <ctype.h> 65#include <errno.h> 66#include <memory.h> 67#include <stdio.h> 68#include <stdlib.h> 69#include <string.h> 70#if !defined(WIN32) && !defined(__BORLANDC__) 71#include <unistd.h> 72#endif /* !WIN32 && !__BORLANDC__ */ 73#ifdef HAVE_LIMITS_H 74#include <limits.h> 75#else 76#define INT_MAX 2147483647 77#endif 78 79#include "pcap-int.h" 80 81#ifdef HAVE_OS_PROTO_H 82#include "os-proto.h" 83#endif 84 85/* Not all systems have IFF_LOOPBACK */ 86#ifdef IFF_LOOPBACK 87#define ISLOOPBACK(name, flags) ((flags) & IFF_LOOPBACK) 88#else 89#define ISLOOPBACK(name, flags) ((name)[0] == 'l' && (name)[1] == 'o' && \ 90 (isdigit((unsigned char)((name)[2])) || (name)[2] == '\0')) 91#endif 92 93struct sockaddr * 94dup_sockaddr(struct sockaddr *sa, size_t sa_length) 95{ 96 struct sockaddr *newsa; 97 98 if ((newsa = malloc(sa_length)) == NULL) 99 return (NULL); 100 return (memcpy(newsa, sa, sa_length)); 101} 102 103static int 104get_instance(const char *name) 105{ 106 const char *cp, *endcp; 107 int n; 108 109 if (strcmp(name, "any") == 0) { 110 /* 111 * Give the "any" device an artificially high instance 112 * number, so it shows up after all other non-loopback 113 * interfaces. 114 */ 115 return INT_MAX; 116 } 117 118 endcp = name + strlen(name); 119 for (cp = name; cp < endcp && !isdigit((unsigned char)*cp); ++cp) 120 continue; 121 122 if (isdigit((unsigned char)*cp)) 123 n = atoi(cp); 124 else 125 n = 0; 126 return (n); 127} 128 129int 130add_or_find_if(pcap_if_t **curdev_ret, pcap_if_t **alldevs, const char *name, 131 u_int flags, const char *description, char *errbuf) 132{ 133 pcap_t *p; 134 pcap_if_t *curdev, *prevdev, *nextdev; 135 int this_instance; 136 137 /* 138 * Is there already an entry in the list for this interface? 139 */ 140 for (curdev = *alldevs; curdev != NULL; curdev = curdev->next) { 141 if (strcmp(name, curdev->name) == 0) 142 break; /* yes, we found it */ 143 } 144 145 if (curdev == NULL) { 146 /* 147 * No, we didn't find it. 148 * 149 * Can we open this interface for live capture? 150 * 151 * We do this check so that interfaces that are 152 * supplied by the interface enumeration mechanism 153 * we're using but that don't support packet capture 154 * aren't included in the list. Loopback interfaces 155 * on Solaris are an example of this; we don't just 156 * omit loopback interfaces on all platforms because 157 * you *can* capture on loopback interfaces on some 158 * OSes. 159 * 160 * On OS X, we don't do this check if the device 161 * name begins with "wlt"; at least some versions 162 * of OS X offer monitor mode capturing by having 163 * a separate "monitor mode" device for each wireless 164 * adapter, rather than by implementing the ioctls 165 * that {Free,Net,Open,DragonFly}BSD provide. 166 * Opening that device puts the adapter into monitor 167 * mode, which, at least for some adapters, causes 168 * them to deassociate from the network with which 169 * they're associated. 170 * 171 * Instead, we try to open the corresponding "en" 172 * device (so that we don't end up with, for users 173 * without sufficient privilege to open capture 174 * devices, a list of adapters that only includes 175 * the wlt devices). 176 */ 177#ifdef __APPLE__ 178 if (strncmp(name, "wlt", 3) == 0) { 179 char *en_name; 180 size_t en_name_len; 181 182 /* 183 * Try to allocate a buffer for the "en" 184 * device's name. 185 */ 186 en_name_len = strlen(name) - 1; 187 en_name = malloc(en_name_len + 1); 188 if (en_name == NULL) { 189 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 190 "malloc: %s", pcap_strerror(errno)); 191 return (-1); 192 } 193 strcpy(en_name, "en"); 194 strcat(en_name, name + 3); 195 p = pcap_open_live(en_name, 68, 0, 0, errbuf); 196 free(en_name); 197 } else 198#endif /* __APPLE */ 199 p = pcap_open_live(name, 68, 0, 0, errbuf); 200 if (p == NULL) { 201 /* 202 * No. Don't bother including it. 203 * Don't treat this as an error, though. 204 */ 205 *curdev_ret = NULL; 206 return (0); 207 } 208 pcap_close(p); 209 210 /* 211 * Yes, we can open it. 212 * Allocate a new entry. 213 */ 214 curdev = malloc(sizeof(pcap_if_t)); 215 if (curdev == NULL) { 216 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 217 "malloc: %s", pcap_strerror(errno)); 218 return (-1); 219 } 220 221 /* 222 * Fill in the entry. 223 */ 224 curdev->next = NULL; 225 curdev->name = strdup(name); 226 if (curdev->name == NULL) { 227 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 228 "malloc: %s", pcap_strerror(errno)); 229 free(curdev); 230 return (-1); 231 } 232 if (description != NULL) { 233 /* 234 * We have a description for this interface. 235 */ 236 curdev->description = strdup(description); 237 if (curdev->description == NULL) { 238 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 239 "malloc: %s", pcap_strerror(errno)); 240 free(curdev->name); 241 free(curdev); 242 return (-1); 243 } 244 } else { 245 /* 246 * We don't. 247 */ 248 curdev->description = NULL; 249 } 250 curdev->addresses = NULL; /* list starts out as empty */ 251 curdev->flags = 0; 252 if (ISLOOPBACK(name, flags)) 253 curdev->flags |= PCAP_IF_LOOPBACK; 254 255 /* 256 * Add it to the list, in the appropriate location. 257 * First, get the instance number of this interface. 258 */ 259 this_instance = get_instance(name); 260 261 /* 262 * Now look for the last interface with an instance number 263 * less than or equal to the new interface's instance 264 * number - except that non-loopback interfaces are 265 * arbitrarily treated as having interface numbers less 266 * than those of loopback interfaces, so the loopback 267 * interfaces are put at the end of the list. 268 * 269 * We start with "prevdev" being NULL, meaning we're before 270 * the first element in the list. 271 */ 272 prevdev = NULL; 273 for (;;) { 274 /* 275 * Get the interface after this one. 276 */ 277 if (prevdev == NULL) { 278 /* 279 * The next element is the first element. 280 */ 281 nextdev = *alldevs; 282 } else 283 nextdev = prevdev->next; 284 285 /* 286 * Are we at the end of the list? 287 */ 288 if (nextdev == NULL) { 289 /* 290 * Yes - we have to put the new entry 291 * after "prevdev". 292 */ 293 break; 294 } 295 296 /* 297 * Is the new interface a non-loopback interface 298 * and the next interface a loopback interface? 299 */ 300 if (!(curdev->flags & PCAP_IF_LOOPBACK) && 301 (nextdev->flags & PCAP_IF_LOOPBACK)) { 302 /* 303 * Yes, we should put the new entry 304 * before "nextdev", i.e. after "prevdev". 305 */ 306 break; 307 } 308 309 /* 310 * Is the new interface's instance number less 311 * than the next interface's instance number, 312 * and is it the case that the new interface is a 313 * non-loopback interface or the next interface is 314 * a loopback interface? 315 * 316 * (The goal of both loopback tests is to make 317 * sure that we never put a loopback interface 318 * before any non-loopback interface and that we 319 * always put a non-loopback interface before all 320 * loopback interfaces.) 321 */ 322 if (this_instance < get_instance(nextdev->name) && 323 (!(curdev->flags & PCAP_IF_LOOPBACK) || 324 (nextdev->flags & PCAP_IF_LOOPBACK))) { 325 /* 326 * Yes - we should put the new entry 327 * before "nextdev", i.e. after "prevdev". 328 */ 329 break; 330 } 331 332 prevdev = nextdev; 333 } 334 335 /* 336 * Insert before "nextdev". 337 */ 338 curdev->next = nextdev; 339 340 /* 341 * Insert after "prevdev" - unless "prevdev" is null, 342 * in which case this is the first interface. 343 */ 344 if (prevdev == NULL) { 345 /* 346 * This is the first interface. Pass back a 347 * pointer to it, and put "curdev" before 348 * "nextdev". 349 */ 350 *alldevs = curdev; 351 } else 352 prevdev->next = curdev; 353 } 354 355 *curdev_ret = curdev; 356 return (0); 357} 358 359/* 360 * XXX - on FreeBSDs that support it, should it get the sysctl named 361 * "dev.{adapter family name}.{adapter unit}.%desc" to get a description 362 * of the adapter? Note that "dev.an.0.%desc" is "Aironet PC4500/PC4800" 363 * with my Cisco 350 card, so the name isn't entirely descriptive. The 364 * "dev.an.0.%pnpinfo" has a better description, although one might argue 365 * that the problem is really a driver bug - if it can find out that it's 366 * a Cisco 340 or 350, rather than an old Aironet card, it should use 367 * that in the description. 368 * 369 * Do NetBSD, DragonflyBSD, or OpenBSD support this as well? FreeBSD 370 * and OpenBSD let you get a description, but it's not generated by the OS, 371 * it's set with another ioctl that ifconfig supports; we use that to get 372 * a description in FreeBSD and OpenBSD, but if there is no such 373 * description available, it still might be nice to get some description 374 * string based on the device type or something such as that. 375 * 376 * In OS X, the System Configuration framework can apparently return 377 * names in 10.4 and later. 378 * 379 * It also appears that freedesktop.org's HAL offers an "info.product" 380 * string, but the HAL specification says it "should not be used in any 381 * UI" and "subsystem/capability specific properties" should be used 382 * instead and, in any case, I think HAL is being deprecated in 383 * favor of other stuff such as DeviceKit. DeviceKit doesn't appear 384 * to have any obvious product information for devices, but maybe 385 * I haven't looked hard enough. 386 * 387 * Using the System Configuration framework, or HAL, or DeviceKit, or 388 * whatever, would require that libpcap applications be linked with 389 * the frameworks/libraries in question. That shouldn't be a problem 390 * for programs linking with the shared version of libpcap (unless 391 * you're running on AIX - which I think is the only UN*X that doesn't 392 * support linking a shared library with other libraries on which it 393 * depends, and having an executable linked only with the first shared 394 * library automatically pick up the other libraries when started - 395 * and using HAL or whatever). Programs linked with the static 396 * version of libpcap would have to use pcap-config with the --static 397 * flag in order to get the right linker flags in order to pick up 398 * the additional libraries/frameworks; those programs need that anyway 399 * for libpcap 1.1 and beyond on Linux, as, by default, it requires 400 * -lnl. 401 * 402 * Do any other UN*Xes, or desktop environments support getting a 403 * description? 404 */ 405int 406add_addr_to_iflist(pcap_if_t **alldevs, const char *name, u_int flags, 407 struct sockaddr *addr, size_t addr_size, 408 struct sockaddr *netmask, size_t netmask_size, 409 struct sockaddr *broadaddr, size_t broadaddr_size, 410 struct sockaddr *dstaddr, size_t dstaddr_size, 411 char *errbuf) 412{ 413 pcap_if_t *curdev; 414 char *description = NULL; 415 pcap_addr_t *curaddr, *prevaddr, *nextaddr; 416#ifdef SIOCGIFDESCR 417 int s; 418 struct ifreq ifrdesc; 419#ifndef IFDESCRSIZE 420 size_t descrlen = 64; 421#else 422 size_t descrlen = IFDESCRSIZE; 423#endif /* IFDESCRSIZE */ 424#endif /* SIOCGIFDESCR */ 425 426#ifdef SIOCGIFDESCR 427 /* 428 * Get the description for the interface. 429 */ 430 memset(&ifrdesc, 0, sizeof ifrdesc); 431 strlcpy(ifrdesc.ifr_name, name, sizeof ifrdesc.ifr_name); 432 s = socket(AF_INET, SOCK_DGRAM, 0); 433 if (s >= 0) { 434 for (;;) { 435 free(description); 436 if ((description = malloc(descrlen)) != NULL) { 437#ifdef __FreeBSD__ 438 ifrdesc.ifr_buffer.buffer = description; 439 ifrdesc.ifr_buffer.length = descrlen; 440#else /* __FreeBSD__ */ 441 ifrdesc.ifr_data = (caddr_t)description; 442#endif /* __FreeBSD__ */ 443 if (ioctl(s, SIOCGIFDESCR, &ifrdesc) == 0) 444 break; 445#ifdef __FreeBSD__ 446 else if (errno == ENAMETOOLONG) 447 descrlen = ifrdesc.ifr_buffer.length; 448#endif /* __FreeBSD__ */ 449 else 450 break; 451 } else 452 break; 453 } 454 close(s); 455 if (description != NULL && strlen(description) == 0) { 456 free(description); 457 description = NULL; 458 } 459 } 460#endif /* SIOCGIFDESCR */ 461 462 if (add_or_find_if(&curdev, alldevs, name, flags, description, 463 errbuf) == -1) { 464 free(description); 465 /* 466 * Error - give up. 467 */ 468 return (-1); 469 } 470 free(description); 471 if (curdev == NULL) { 472 /* 473 * Device wasn't added because it can't be opened. 474 * Not a fatal error. 475 */ 476 return (0); 477 } 478 479 /* 480 * "curdev" is an entry for this interface; add an entry for this 481 * address to its list of addresses. 482 * 483 * Allocate the new entry and fill it in. 484 */ 485 curaddr = malloc(sizeof(pcap_addr_t)); 486 if (curaddr == NULL) { 487 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 488 "malloc: %s", pcap_strerror(errno)); 489 return (-1); 490 } 491 492 curaddr->next = NULL; 493 if (addr != NULL) { 494 curaddr->addr = dup_sockaddr(addr, addr_size); 495 if (curaddr->addr == NULL) { 496 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 497 "malloc: %s", pcap_strerror(errno)); 498 free(curaddr); 499 return (-1); 500 } 501 } else 502 curaddr->addr = NULL; 503 504 if (netmask != NULL) { 505 curaddr->netmask = dup_sockaddr(netmask, netmask_size); 506 if (curaddr->netmask == NULL) { 507 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 508 "malloc: %s", pcap_strerror(errno)); 509 if (curaddr->addr != NULL) 510 free(curaddr->addr); 511 free(curaddr); 512 return (-1); 513 } 514 } else 515 curaddr->netmask = NULL; 516 517 if (broadaddr != NULL) { 518 curaddr->broadaddr = dup_sockaddr(broadaddr, broadaddr_size); 519 if (curaddr->broadaddr == NULL) { 520 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 521 "malloc: %s", pcap_strerror(errno)); 522 if (curaddr->netmask != NULL) 523 free(curaddr->netmask); 524 if (curaddr->addr != NULL) 525 free(curaddr->addr); 526 free(curaddr); 527 return (-1); 528 } 529 } else 530 curaddr->broadaddr = NULL; 531 532 if (dstaddr != NULL) { 533 curaddr->dstaddr = dup_sockaddr(dstaddr, dstaddr_size); 534 if (curaddr->dstaddr == NULL) { 535 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 536 "malloc: %s", pcap_strerror(errno)); 537 if (curaddr->broadaddr != NULL) 538 free(curaddr->broadaddr); 539 if (curaddr->netmask != NULL) 540 free(curaddr->netmask); 541 if (curaddr->addr != NULL) 542 free(curaddr->addr); 543 free(curaddr); 544 return (-1); 545 } 546 } else 547 curaddr->dstaddr = NULL; 548 549 /* 550 * Find the end of the list of addresses. 551 */ 552 for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) { 553 nextaddr = prevaddr->next; 554 if (nextaddr == NULL) { 555 /* 556 * This is the end of the list. 557 */ 558 break; 559 } 560 } 561 562 if (prevaddr == NULL) { 563 /* 564 * The list was empty; this is the first member. 565 */ 566 curdev->addresses = curaddr; 567 } else { 568 /* 569 * "prevaddr" is the last member of the list; append 570 * this member to it. 571 */ 572 prevaddr->next = curaddr; 573 } 574 575 return (0); 576} 577 578int 579pcap_add_if(pcap_if_t **devlist, const char *name, u_int flags, 580 const char *description, char *errbuf) 581{ 582 pcap_if_t *curdev; 583 584 return (add_or_find_if(&curdev, devlist, name, flags, description, 585 errbuf)); 586} 587 588 589/* 590 * Free a list of interfaces. 591 */ 592void 593pcap_freealldevs(pcap_if_t *alldevs) 594{ 595 pcap_if_t *curdev, *nextdev; 596 pcap_addr_t *curaddr, *nextaddr; 597 598 for (curdev = alldevs; curdev != NULL; curdev = nextdev) { 599 nextdev = curdev->next; 600 601 /* 602 * Free all addresses. 603 */ 604 for (curaddr = curdev->addresses; curaddr != NULL; curaddr = nextaddr) { 605 nextaddr = curaddr->next; 606 if (curaddr->addr) 607 free(curaddr->addr); 608 if (curaddr->netmask) 609 free(curaddr->netmask); 610 if (curaddr->broadaddr) 611 free(curaddr->broadaddr); 612 if (curaddr->dstaddr) 613 free(curaddr->dstaddr); 614 free(curaddr); 615 } 616 617 /* 618 * Free the name string. 619 */ 620 free(curdev->name); 621 622 /* 623 * Free the description string, if any. 624 */ 625 if (curdev->description != NULL) 626 free(curdev->description); 627 628 /* 629 * Free the interface. 630 */ 631 free(curdev); 632 } 633} 634 635#if !defined(WIN32) && !defined(MSDOS) 636 637/* 638 * Return the name of a network interface attached to the system, or NULL 639 * if none can be found. The interface must be configured up; the 640 * lowest unit number is preferred; loopback is ignored. 641 */ 642char * 643pcap_lookupdev(errbuf) 644 register char *errbuf; 645{ 646 pcap_if_t *alldevs; 647/* for old BSD systems, including bsdi3 */ 648#ifndef IF_NAMESIZE 649#define IF_NAMESIZE IFNAMSIZ 650#endif 651 static char device[IF_NAMESIZE + 1]; 652 char *ret; 653 654 if (pcap_findalldevs(&alldevs, errbuf) == -1) 655 return (NULL); 656 657 if (alldevs == NULL || (alldevs->flags & PCAP_IF_LOOPBACK)) { 658 /* 659 * There are no devices on the list, or the first device 660 * on the list is a loopback device, which means there 661 * are no non-loopback devices on the list. This means 662 * we can't return any device. 663 * 664 * XXX - why not return a loopback device? If we can't 665 * capture on it, it won't be on the list, and if it's 666 * on the list, there aren't any non-loopback devices, 667 * so why not just supply it as the default device? 668 */ 669 (void)strlcpy(errbuf, "no suitable device found", 670 PCAP_ERRBUF_SIZE); 671 ret = NULL; 672 } else { 673 /* 674 * Return the name of the first device on the list. 675 */ 676 (void)strlcpy(device, alldevs->name, sizeof(device)); 677 ret = device; 678 } 679 680 pcap_freealldevs(alldevs); 681 return (ret); 682} 683 684int 685pcap_lookupnet(device, netp, maskp, errbuf) 686 register const char *device; 687 register bpf_u_int32 *netp, *maskp; 688 register char *errbuf; 689{ 690 register int fd; 691 register struct sockaddr_in *sin4; 692 struct ifreq ifr; 693 694 /* 695 * The pseudo-device "any" listens on all interfaces and therefore 696 * has the network address and -mask "0.0.0.0" therefore catching 697 * all traffic. Using NULL for the interface is the same as "any". 698 */ 699 if (!device || strcmp(device, "any") == 0 700#ifdef HAVE_DAG_API 701 || strstr(device, "dag") != NULL 702#endif 703#ifdef HAVE_SEPTEL_API 704 || strstr(device, "septel") != NULL 705#endif 706#ifdef PCAP_SUPPORT_BT 707 || strstr(device, "bluetooth") != NULL 708#endif 709#ifdef PCAP_SUPPORT_USB 710 || strstr(device, "usbmon") != NULL 711#endif 712#ifdef HAVE_SNF_API 713 || strstr(device, "snf") != NULL 714#endif 715 ) { 716 *netp = *maskp = 0; 717 return 0; 718 } 719 720 fd = socket(AF_INET, SOCK_DGRAM, 0); 721 if (fd < 0) { 722 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "socket: %s", 723 pcap_strerror(errno)); 724 return (-1); 725 } 726 memset(&ifr, 0, sizeof(ifr)); 727#ifdef linux 728 /* XXX Work around Linux kernel bug */ 729 ifr.ifr_addr.sa_family = AF_INET; 730#endif 731 (void)strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name)); 732 if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0) { 733 if (errno == EADDRNOTAVAIL) { 734 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 735 "%s: no IPv4 address assigned", device); 736 } else { 737 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 738 "SIOCGIFADDR: %s: %s", 739 device, pcap_strerror(errno)); 740 } 741 (void)close(fd); 742 return (-1); 743 } 744 sin4 = (struct sockaddr_in *)&ifr.ifr_addr; 745 *netp = sin4->sin_addr.s_addr; 746 memset(&ifr, 0, sizeof(ifr)); 747#ifdef linux 748 /* XXX Work around Linux kernel bug */ 749 ifr.ifr_addr.sa_family = AF_INET; 750#endif 751 (void)strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name)); 752 if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifr) < 0) { 753 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 754 "SIOCGIFNETMASK: %s: %s", device, pcap_strerror(errno)); 755 (void)close(fd); 756 return (-1); 757 } 758 (void)close(fd); 759 *maskp = sin4->sin_addr.s_addr; 760 if (*maskp == 0) { 761 if (IN_CLASSA(*netp)) 762 *maskp = IN_CLASSA_NET; 763 else if (IN_CLASSB(*netp)) 764 *maskp = IN_CLASSB_NET; 765 else if (IN_CLASSC(*netp)) 766 *maskp = IN_CLASSC_NET; 767 else { 768 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 769 "inet class for 0x%x unknown", *netp); 770 return (-1); 771 } 772 } 773 *netp &= *maskp; 774 return (0); 775} 776 777#elif defined(WIN32) 778 779/* 780 * Return the name of a network interface attached to the system, or NULL 781 * if none can be found. The interface must be configured up; the 782 * lowest unit number is preferred; loopback is ignored. 783 */ 784char * 785pcap_lookupdev(errbuf) 786 register char *errbuf; 787{ 788 DWORD dwVersion; 789 DWORD dwWindowsMajorVersion; 790 dwVersion = GetVersion(); /* get the OS version */ 791 dwWindowsMajorVersion = (DWORD)(LOBYTE(LOWORD(dwVersion))); 792 793 if (dwVersion >= 0x80000000 && dwWindowsMajorVersion >= 4) { 794 /* 795 * Windows 95, 98, ME. 796 */ 797 ULONG NameLength = 8192; 798 static char AdaptersName[8192]; 799 800 if (PacketGetAdapterNames(AdaptersName,&NameLength) ) 801 return (AdaptersName); 802 else 803 return NULL; 804 } else { 805 /* 806 * Windows NT (NT 4.0, W2K, WXP). Convert the names to UNICODE for backward compatibility 807 */ 808 ULONG NameLength = 8192; 809 static WCHAR AdaptersName[8192]; 810 char *tAstr; 811 WCHAR *tUstr; 812 WCHAR *TAdaptersName = (WCHAR*)malloc(8192 * sizeof(WCHAR)); 813 int NAdapts = 0; 814 815 if(TAdaptersName == NULL) 816 { 817 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "memory allocation failure"); 818 return NULL; 819 } 820 821 if ( !PacketGetAdapterNames((PTSTR)TAdaptersName,&NameLength) ) 822 { 823 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, 824 "PacketGetAdapterNames: %s", 825 pcap_win32strerror()); 826 free(TAdaptersName); 827 return NULL; 828 } 829 830 831 tAstr = (char*)TAdaptersName; 832 tUstr = (WCHAR*)AdaptersName; 833 834 /* 835 * Convert and copy the device names 836 */ 837 while(sscanf(tAstr, "%S", tUstr) > 0) 838 { 839 tAstr += strlen(tAstr) + 1; 840 tUstr += wcslen(tUstr) + 1; 841 NAdapts ++; 842 } 843 844 tAstr++; 845 *tUstr = 0; 846 tUstr++; 847 848 /* 849 * Copy the descriptions 850 */ 851 while(NAdapts--) 852 { 853 strcpy((char*)tUstr, tAstr); 854 (char*)tUstr += strlen(tAstr) + 1;; 855 tAstr += strlen(tAstr) + 1; 856 } 857 858 free(TAdaptersName); 859 return (char *)(AdaptersName); 860 } 861} 862 863 864int 865pcap_lookupnet(device, netp, maskp, errbuf) 866 register const char *device; 867 register bpf_u_int32 *netp, *maskp; 868 register char *errbuf; 869{ 870 /* 871 * We need only the first IPv4 address, so we must scan the array returned by PacketGetNetInfo() 872 * in order to skip non IPv4 (i.e. IPv6 addresses) 873 */ 874 npf_if_addr if_addrs[MAX_NETWORK_ADDRESSES]; 875 LONG if_addr_size = 1; 876 struct sockaddr_in *t_addr; 877 unsigned int i; 878 879 if (!PacketGetNetInfoEx((void *)device, if_addrs, &if_addr_size)) { 880 *netp = *maskp = 0; 881 return (0); 882 } 883 884 for(i=0; i<MAX_NETWORK_ADDRESSES; i++) 885 { 886 if(if_addrs[i].IPAddress.ss_family == AF_INET) 887 { 888 t_addr = (struct sockaddr_in *) &(if_addrs[i].IPAddress); 889 *netp = t_addr->sin_addr.S_un.S_addr; 890 t_addr = (struct sockaddr_in *) &(if_addrs[i].SubnetMask); 891 *maskp = t_addr->sin_addr.S_un.S_addr; 892 893 *netp &= *maskp; 894 return (0); 895 } 896 897 } 898 899 *netp = *maskp = 0; 900 return (0); 901} 902 903#endif /* !WIN32 && !MSDOS */ 904