contrib/libpcap-0.9/inet.c

   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
  36 static const char rcsid[] _U_ =
  37     "@(#) $Header: /tcpdump/master/libpcap/inet.c,v 1.66.2.6 2007/06/11 09:52:04 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
  58 struct mbuf;            /* Squelch compiler warnings on some platforms for */
  59 struct 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
  93 struct sockaddr *
  94 dup_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
 103 static int
 104 get_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
 129 int
 130 add_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 int
 360 add_addr_to_iflist(pcap_if_t **alldevs, const char *name, u_int flags,
 361     struct sockaddr *addr, size_t addr_size,
 362     struct sockaddr *netmask, size_t netmask_size,
 363     struct sockaddr *broadaddr, size_t broadaddr_size,
 364     struct sockaddr *dstaddr, size_t dstaddr_size,
 365     char *errbuf)
 366 {
 367         pcap_if_t *curdev;
 368         pcap_addr_t *curaddr, *prevaddr, *nextaddr;
 369
 370         if (add_or_find_if(&curdev, alldevs, name, flags, NULL, errbuf) == -1) {
 371                 /*
 372                  * Error - give up.
 373                  */
 374                 return (-1);
 375         }
 376         if (curdev == NULL) {
 377                 /*
 378                  * Device wasn't added because it can't be opened.
 379                  * Not a fatal error.
 380                  */
 381                 return (0);
 382         }
 383
 384         /*
 385          * "curdev" is an entry for this interface; add an entry for this
 386          * address to its list of addresses.
 387          *
 388          * Allocate the new entry and fill it in.
 389          */
 390         curaddr = malloc(sizeof(pcap_addr_t));
 391         if (curaddr == NULL) {
 392                 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 393                     "malloc: %s", pcap_strerror(errno));
 394                 return (-1);
 395         }
 396
 397         curaddr->next = NULL;
 398         if (addr != NULL) {
 399                 curaddr->addr = dup_sockaddr(addr, addr_size);
 400                 if (curaddr->addr == NULL) {
 401                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 402                             "malloc: %s", pcap_strerror(errno));
 403                         free(curaddr);
 404                         return (-1);
 405                 }
 406         } else
 407                 curaddr->addr = NULL;
 408
 409         if (netmask != NULL) {
 410                 curaddr->netmask = dup_sockaddr(netmask, netmask_size);
 411                 if (curaddr->netmask == NULL) {
 412                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 413                             "malloc: %s", pcap_strerror(errno));
 414                         if (curaddr->addr != NULL)
 415                                 free(curaddr->addr);
 416                         free(curaddr);
 417                         return (-1);
 418                 }
 419         } else
 420                 curaddr->netmask = NULL;
 421
 422         if (broadaddr != NULL) {
 423                 curaddr->broadaddr = dup_sockaddr(broadaddr, broadaddr_size);
 424                 if (curaddr->broadaddr == NULL) {
 425                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 426                             "malloc: %s", pcap_strerror(errno));
 427                         if (curaddr->netmask != NULL)
 428                                 free(curaddr->netmask);
 429                         if (curaddr->addr != NULL)
 430                                 free(curaddr->addr);
 431                         free(curaddr);
 432                         return (-1);
 433                 }
 434         } else
 435                 curaddr->broadaddr = NULL;
 436
 437         if (dstaddr != NULL) {
 438                 curaddr->dstaddr = dup_sockaddr(dstaddr, dstaddr_size);
 439                 if (curaddr->dstaddr == NULL) {
 440                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 441                             "malloc: %s", pcap_strerror(errno));
 442                         if (curaddr->broadaddr != NULL)
 443                                 free(curaddr->broadaddr);
 444                         if (curaddr->netmask != NULL)
 445                                 free(curaddr->netmask);
 446                         if (curaddr->addr != NULL)
 447                                 free(curaddr->addr);
 448                         free(curaddr);
 449                         return (-1);
 450                 }
 451         } else
 452                 curaddr->dstaddr = NULL;
 453
 454         /*
 455          * Find the end of the list of addresses.
 456          */
 457         for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) {
 458                 nextaddr = prevaddr->next;
 459                 if (nextaddr == NULL) {
 460                         /*
 461                          * This is the end of the list.
 462                          */
 463                         break;
 464                 }
 465         }
 466
 467         if (prevaddr == NULL) {
 468                 /*
 469                  * The list was empty; this is the first member.
 470                  */
 471                 curdev->addresses = curaddr;
 472         } else {
 473                 /*
 474                  * "prevaddr" is the last member of the list; append
 475                  * this member to it.
 476                  */
 477                 prevaddr->next = curaddr;
 478         }
 479
 480         return (0);
 481 }
 482
 483 int
 484 pcap_add_if(pcap_if_t **devlist, const char *name, u_int flags,
 485     const char *description, char *errbuf)
 486 {
 487         pcap_if_t *curdev;
 488
 489         return (add_or_find_if(&curdev, devlist, name, flags, description,
 490             errbuf));
 491 }
 492
 493
 494 /*
 495  * Free a list of interfaces.
 496  */
 497 void
 498 pcap_freealldevs(pcap_if_t *alldevs)
 499 {
 500         pcap_if_t *curdev, *nextdev;
 501         pcap_addr_t *curaddr, *nextaddr;
 502
 503         for (curdev = alldevs; curdev != NULL; curdev = nextdev) {
 504                 nextdev = curdev->next;
 505
 506                 /*
 507                  * Free all addresses.
 508                  */
 509                 for (curaddr = curdev->addresses; curaddr != NULL; curaddr = nextaddr) {
 510                         nextaddr = curaddr->next;
 511                         if (curaddr->addr)
 512                                 free(curaddr->addr);
 513                         if (curaddr->netmask)
 514                                 free(curaddr->netmask);
 515                         if (curaddr->broadaddr)
 516                                 free(curaddr->broadaddr);
 517                         if (curaddr->dstaddr)
 518                                 free(curaddr->dstaddr);
 519                         free(curaddr);
 520                 }
 521
 522                 /*
 523                  * Free the name string.
 524                  */
 525                 free(curdev->name);
 526
 527                 /*
 528                  * Free the description string, if any.
 529                  */
 530                 if (curdev->description != NULL)
 531                         free(curdev->description);
 532
 533                 /*
 534                  * Free the interface.
 535                  */
 536                 free(curdev);
 537         }
 538 }
 539
 540 #if !defined(WIN32) && !defined(MSDOS)
 541
 542 /*
 543  * Return the name of a network interface attached to the system, or NULL
 544  * if none can be found.  The interface must be configured up; the
 545  * lowest unit number is preferred; loopback is ignored.
 546  */
 547 char *
 548 pcap_lookupdev(errbuf)
 549         register char *errbuf;
 550 {
 551         pcap_if_t *alldevs;
 552 /* for old BSD systems, including bsdi3 */
 553 #ifndef IF_NAMESIZE
 554 #define IF_NAMESIZE IFNAMSIZ
 555 #endif
 556         static char device[IF_NAMESIZE + 1];
 557         char *ret;
 558
 559         if (pcap_findalldevs(&alldevs, errbuf) == -1)
 560                 return (NULL);
 561
 562         if (alldevs == NULL || (alldevs->flags & PCAP_IF_LOOPBACK)) {
 563                 /*
 564                  * There are no devices on the list, or the first device
 565                  * on the list is a loopback device, which means there
 566                  * are no non-loopback devices on the list.  This means
 567                  * we can't return any device.
 568                  *
 569                  * XXX - why not return a loopback device?  If we can't
 570                  * capture on it, it won't be on the list, and if it's
 571                  * on the list, there aren't any non-loopback devices,
 572                  * so why not just supply it as the default device?
 573                  */
 574                 (void)strlcpy(errbuf, "no suitable device found",
 575                     PCAP_ERRBUF_SIZE);
 576                 ret = NULL;
 577         } else {
 578                 /*
 579                  * Return the name of the first device on the list.
 580                  */
 581                 (void)strlcpy(device, alldevs->name, sizeof(device));
 582                 ret = device;
 583         }
 584
 585         pcap_freealldevs(alldevs);
 586         return (ret);
 587 }
 588
 589 int
 590 pcap_lookupnet(device, netp, maskp, errbuf)
 591         register const char *device;
 592         register bpf_u_int32 *netp, *maskp;
 593         register char *errbuf;
 594 {
 595         register int fd;
 596         register struct sockaddr_in *sin4;
 597         struct ifreq ifr;
 598
 599         /*
 600          * The pseudo-device "any" listens on all interfaces and therefore
 601          * has the network address and -mask "0.0.0.0" therefore catching
 602          * all traffic. Using NULL for the interface is the same as "any".
 603          */
 604         if (!device || strcmp(device, "any") == 0
 605 #ifdef HAVE_DAG_API
 606             || strstr(device, "dag") != NULL
 607 #endif
 608 #ifdef HAVE_SEPTEL_API
 609             || strstr(device, "septel") != NULL
 610 #endif
 611             ) {
 612                 *netp = *maskp = 0;
 613                 return 0;
 614         }
 615
 616         fd = socket(AF_INET, SOCK_DGRAM, 0);
 617         if (fd < 0) {
 618                 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "socket: %s",
 619                     pcap_strerror(errno));
 620                 return (-1);
 621         }
 622         memset(&ifr, 0, sizeof(ifr));
 623 #ifdef linux
 624         /* XXX Work around Linux kernel bug */
 625         ifr.ifr_addr.sa_family = AF_INET;
 626 #endif
 627         (void)strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
 628         if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0) {
 629                 if (errno == EADDRNOTAVAIL) {
 630                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 631                             "%s: no IPv4 address assigned", device);
 632                 } else {
 633                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 634                             "SIOCGIFADDR: %s: %s",
 635                             device, pcap_strerror(errno));
 636                 }
 637                 (void)close(fd);
 638                 return (-1);
 639         }
 640         sin4 = (struct sockaddr_in *)&ifr.ifr_addr;
 641         *netp = sin4->sin_addr.s_addr;
 642         if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifr) < 0) {
 643                 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 644                     "SIOCGIFNETMASK: %s: %s", device, pcap_strerror(errno));
 645                 (void)close(fd);
 646                 return (-1);
 647         }
 648         (void)close(fd);
 649         *maskp = sin4->sin_addr.s_addr;
 650         if (*maskp == 0) {
 651                 if (IN_CLASSA(*netp))
 652                         *maskp = IN_CLASSA_NET;
 653                 else if (IN_CLASSB(*netp))
 654                         *maskp = IN_CLASSB_NET;
 655                 else if (IN_CLASSC(*netp))
 656                         *maskp = IN_CLASSC_NET;
 657                 else {
 658                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 659                             "inet class for 0x%x unknown", *netp);
 660                         return (-1);
 661                 }
 662         }
 663         *netp &= *maskp;
 664         return (0);
 665 }
 666
 667 #elif defined(WIN32)
 668
 669 /*
 670  * Return the name of a network interface attached to the system, or NULL
 671  * if none can be found.  The interface must be configured up; the
 672  * lowest unit number is preferred; loopback is ignored.
 673  */
 674 char *
 675 pcap_lookupdev(errbuf)
 676         register char *errbuf;
 677 {
 678         DWORD dwVersion;
 679         DWORD dwWindowsMajorVersion;
 680         dwVersion = GetVersion();       /* get the OS version */
 681         dwWindowsMajorVersion = (DWORD)(LOBYTE(LOWORD(dwVersion)));
 682
 683         if (dwVersion >= 0x80000000 && dwWindowsMajorVersion >= 4) {
 684                 /*
 685                  * Windows 95, 98, ME.
 686                  */
 687                 ULONG NameLength = 8192;
 688                 static char AdaptersName[8192];
 689
 690                 if (PacketGetAdapterNames(AdaptersName,&NameLength) )
 691                         return (AdaptersName);
 692                 else
 693                         return NULL;
 694         } else {
 695                 /*
 696                  * Windows NT (NT 4.0, W2K, WXP). Convert the names to UNICODE for backward compatibility
 697                  */
 698                 ULONG NameLength = 8192;
 699                 static WCHAR AdaptersName[8192];
 700                 char *tAstr;
 701                 WCHAR *tUstr;
 702                 WCHAR *TAdaptersName = (WCHAR*)malloc(8192 * sizeof(WCHAR));
 703                 int NAdapts = 0;
 704
 705                 if(TAdaptersName == NULL)
 706                 {
 707                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, "memory allocation failure");
 708                         return NULL;
 709                 }
 710
 711                 if ( !PacketGetAdapterNames((PTSTR)TAdaptersName,&NameLength) )
 712                 {
 713                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 714                                 "PacketGetAdapterNames: %s",
 715                                 pcap_win32strerror());
 716                         free(TAdaptersName);
 717                         return NULL;
 718                 }
 719
 720
 721                 tAstr = (char*)TAdaptersName;
 722                 tUstr = (WCHAR*)AdaptersName;
 723
 724                 /*
 725                  * Convert and copy the device names
 726                  */
 727                 while(sscanf(tAstr, "%S", tUstr) > 0)
 728                 {
 729                         tAstr += strlen(tAstr) + 1;
 730                         tUstr += wcslen(tUstr) + 1;
 731                         NAdapts ++;
 732                 }
 733
 734                 tAstr++;
 735                 *tUstr = 0;
 736                 tUstr++;
 737
 738                 /*
 739                  * Copy the descriptions
 740                  */
 741                 while(NAdapts--)
 742                 {
 743                         strcpy((char*)tUstr, tAstr);
 744                         (char*)tUstr += strlen(tAstr) + 1;;
 745                         tAstr += strlen(tAstr) + 1;
 746                 }
 747
 748                 free(TAdaptersName);
 749                 return (char *)(AdaptersName);
 750         }
 751 }
 752
 753
 754 int
 755 pcap_lookupnet(device, netp, maskp, errbuf)
 756         register const char *device;
 757         register bpf_u_int32 *netp, *maskp;
 758         register char *errbuf;
 759 {
 760         /*
 761          * We need only the first IPv4 address, so we must scan the array returned by PacketGetNetInfo()
 762          * in order to skip non IPv4 (i.e. IPv6 addresses)
 763          */
 764         npf_if_addr if_addrs[MAX_NETWORK_ADDRESSES];
 765         LONG if_addr_size = 1;
 766         struct sockaddr_in *t_addr;
 767         unsigned int i;
 768
 769         if (!PacketGetNetInfoEx((void *)device, if_addrs, &if_addr_size)) {
 770                 *netp = *maskp = 0;
 771                 return (0);
 772         }
 773
 774         for(i=0; i<MAX_NETWORK_ADDRESSES; i++)
 775         {
 776                 if(if_addrs[i].IPAddress.ss_family == AF_INET)
 777                 {
 778                         t_addr = (struct sockaddr_in *) &(if_addrs[i].IPAddress);
 779                         *netp = t_addr->sin_addr.S_un.S_addr;
 780                         t_addr = (struct sockaddr_in *) &(if_addrs[i].SubnetMask);
 781                         *maskp = t_addr->sin_addr.S_un.S_addr;
 782
 783                         *netp &= *maskp;
 784                         return (0);
 785                 }
 786
 787         }
 788
 789         *netp = *maskp = 0;
 790         return (0);
 791 }
 792
 793 #endif /* !WIN32 && !MSDOS */