contrib/libpcap/fad-glifc.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 #ifdef HAVE_CONFIG_H
  36 #include "config.h"
  37 #endif
  38
  39 #include <sys/param.h>
  40 #include <sys/file.h>
  41 #include <sys/ioctl.h>
  42 #include <sys/socket.h>
  43 #ifdef HAVE_SYS_SOCKIO_H
  44 #include <sys/sockio.h>
  45 #endif
  46 #include <sys/time.h>                           /* concession to AIX */
  47
  48 struct mbuf;            /* Squelch compiler warnings on some platforms for */
  49 struct rtentry;         /* declarations in <net/if.h> */
  50 #include <net/if.h>
  51 #include <netinet/in.h>
  52
  53 #include <ctype.h>
  54 #include <errno.h>
  55 #include <memory.h>
  56 #include <stdio.h>
  57 #include <stdlib.h>
  58 #include <string.h>
  59 #include <unistd.h>
  60
  61 #include "pcap-int.h"
  62
  63 #ifdef HAVE_OS_PROTO_H
  64 #include "os-proto.h"
  65 #endif
  66
  67 /*
  68  * Get a list of all interfaces that are up and that we can open.
  69  * Returns -1 on error, 0 otherwise.
  70  * The list, as returned through "alldevsp", may be null if no interfaces
  71  * were up and could be opened.
  72  *
  73  * This is the implementation used on platforms that have SIOCGLIFCONF
  74  * but don't have "getifaddrs()".  (Solaris 8 and later; we use
  75  * SIOCGLIFCONF rather than SIOCGIFCONF in order to get IPv6 addresses.)
  76  */
  77 int
  78 pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
  79     int (*check_usable)(const char *))
  80 {
  81         pcap_if_t *devlist = NULL;
  82         register int fd4, fd6, fd;
  83         register struct lifreq *ifrp, *ifend;
  84         struct lifnum ifn;
  85         struct lifconf ifc;
  86         char *buf = NULL;
  87         unsigned buf_size;
  88 #ifdef HAVE_SOLARIS
  89         char *p, *q;
  90 #endif
  91         struct lifreq ifrflags, ifrnetmask, ifrbroadaddr, ifrdstaddr;
  92         struct sockaddr *netmask, *broadaddr, *dstaddr;
  93         int ret = 0;
  94
  95         /*
  96          * Create a socket from which to fetch the list of interfaces,
  97          * and from which to fetch IPv4 information.
  98          */
  99         fd4 = socket(AF_INET, SOCK_DGRAM, 0);
 100         if (fd4 < 0) {
 101                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 102                     "socket: %s", pcap_strerror(errno));
 103                 return (-1);
 104         }
 105
 106         /*
 107          * Create a socket from which to fetch IPv6 information.
 108          */
 109         fd6 = socket(AF_INET6, SOCK_DGRAM, 0);
 110         if (fd6 < 0) {
 111                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 112                     "socket: %s", pcap_strerror(errno));
 113                 (void)close(fd4);
 114                 return (-1);
 115         }
 116
 117         /*
 118          * How many entries will SIOCGLIFCONF return?
 119          */
 120         ifn.lifn_family = AF_UNSPEC;
 121         ifn.lifn_flags = 0;
 122         ifn.lifn_count = 0;
 123         if (ioctl(fd4, SIOCGLIFNUM, (char *)&ifn) < 0) {
 124                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 125                     "SIOCGLIFNUM: %s", pcap_strerror(errno));
 126                 (void)close(fd6);
 127                 (void)close(fd4);
 128                 return (-1);
 129         }
 130
 131         /*
 132          * Allocate a buffer for those entries.
 133          */
 134         buf_size = ifn.lifn_count * sizeof (struct lifreq);
 135         buf = malloc(buf_size);
 136         if (buf == NULL) {
 137                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 138                     "malloc: %s", pcap_strerror(errno));
 139                 (void)close(fd6);
 140                 (void)close(fd4);
 141                 return (-1);
 142         }
 143
 144         /*
 145          * Get the entries.
 146          */
 147         ifc.lifc_len = buf_size;
 148         ifc.lifc_buf = buf;
 149         ifc.lifc_family = AF_UNSPEC;
 150         ifc.lifc_flags = 0;
 151         memset(buf, 0, buf_size);
 152         if (ioctl(fd4, SIOCGLIFCONF, (char *)&ifc) < 0) {
 153                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 154                     "SIOCGLIFCONF: %s", pcap_strerror(errno));
 155                 (void)close(fd6);
 156                 (void)close(fd4);
 157                 free(buf);
 158                 return (-1);
 159         }
 160
 161         /*
 162          * Loop over the entries.
 163          */
 164         ifrp = (struct lifreq *)buf;
 165         ifend = (struct lifreq *)(buf + ifc.lifc_len);
 166
 167         for (; ifrp < ifend; ifrp++) {
 168                 /*
 169                  * Skip entries that begin with "dummy".
 170                  * XXX - what are these?  Is this Linux-specific?
 171                  * Are there platforms on which we shouldn't do this?
 172                  */
 173                 if (strncmp(ifrp->lifr_name, "dummy", 5) == 0)
 174                         continue;
 175
 176                 /*
 177                  * Can we capture on this device?
 178                  */
 179                 if (!(*check_usable)(ifrp->lifr_name)) {
 180                         /*
 181                          * No.
 182                          */
 183                         continue;
 184                 }
 185
 186                 /*
 187                  * IPv6 or not?
 188                  */
 189                 if (((struct sockaddr *)&ifrp->lifr_addr)->sa_family == AF_INET6)
 190                         fd = fd6;
 191                 else
 192                         fd = fd4;
 193
 194                 /*
 195                  * Get the flags for this interface.
 196                  */
 197                 strncpy(ifrflags.lifr_name, ifrp->lifr_name,
 198                     sizeof(ifrflags.lifr_name));
 199                 if (ioctl(fd, SIOCGLIFFLAGS, (char *)&ifrflags) < 0) {
 200                         if (errno == ENXIO)
 201                                 continue;
 202                         (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 203                             "SIOCGLIFFLAGS: %.*s: %s",
 204                             (int)sizeof(ifrflags.lifr_name),
 205                             ifrflags.lifr_name,
 206                             pcap_strerror(errno));
 207                         ret = -1;
 208                         break;
 209                 }
 210
 211                 /*
 212                  * Get the netmask for this address on this interface.
 213                  */
 214                 strncpy(ifrnetmask.lifr_name, ifrp->lifr_name,
 215                     sizeof(ifrnetmask.lifr_name));
 216                 memcpy(&ifrnetmask.lifr_addr, &ifrp->lifr_addr,
 217                     sizeof(ifrnetmask.lifr_addr));
 218                 if (ioctl(fd, SIOCGLIFNETMASK, (char *)&ifrnetmask) < 0) {
 219                         if (errno == EADDRNOTAVAIL) {
 220                                 /*
 221                                  * Not available.
 222                                  */
 223                                 netmask = NULL;
 224                         } else {
 225                                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 226                                     "SIOCGLIFNETMASK: %.*s: %s",
 227                                     (int)sizeof(ifrnetmask.lifr_name),
 228                                     ifrnetmask.lifr_name,
 229                                     pcap_strerror(errno));
 230                                 ret = -1;
 231                                 break;
 232                         }
 233                 } else
 234                         netmask = (struct sockaddr *)&ifrnetmask.lifr_addr;
 235
 236                 /*
 237                  * Get the broadcast address for this address on this
 238                  * interface (if any).
 239                  */
 240                 if (ifrflags.lifr_flags & IFF_BROADCAST) {
 241                         strncpy(ifrbroadaddr.lifr_name, ifrp->lifr_name,
 242                             sizeof(ifrbroadaddr.lifr_name));
 243                         memcpy(&ifrbroadaddr.lifr_addr, &ifrp->lifr_addr,
 244                             sizeof(ifrbroadaddr.lifr_addr));
 245                         if (ioctl(fd, SIOCGLIFBRDADDR,
 246                             (char *)&ifrbroadaddr) < 0) {
 247                                 if (errno == EADDRNOTAVAIL) {
 248                                         /*
 249                                          * Not available.
 250                                          */
 251                                         broadaddr = NULL;
 252                                 } else {
 253                                         (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 254                                             "SIOCGLIFBRDADDR: %.*s: %s",
 255                                             (int)sizeof(ifrbroadaddr.lifr_name),
 256                                             ifrbroadaddr.lifr_name,
 257                                             pcap_strerror(errno));
 258                                         ret = -1;
 259                                         break;
 260                                 }
 261                         } else
 262                                 broadaddr = (struct sockaddr *)&ifrbroadaddr.lifr_broadaddr;
 263                 } else {
 264                         /*
 265                          * Not a broadcast interface, so no broadcast
 266                          * address.
 267                          */
 268                         broadaddr = NULL;
 269                 }
 270
 271                 /*
 272                  * Get the destination address for this address on this
 273                  * interface (if any).
 274                  */
 275                 if (ifrflags.lifr_flags & IFF_POINTOPOINT) {
 276                         strncpy(ifrdstaddr.lifr_name, ifrp->lifr_name,
 277                             sizeof(ifrdstaddr.lifr_name));
 278                         memcpy(&ifrdstaddr.lifr_addr, &ifrp->lifr_addr,
 279                             sizeof(ifrdstaddr.lifr_addr));
 280                         if (ioctl(fd, SIOCGLIFDSTADDR,
 281                             (char *)&ifrdstaddr) < 0) {
 282                                 if (errno == EADDRNOTAVAIL) {
 283                                         /*
 284                                          * Not available.
 285                                          */
 286                                         dstaddr = NULL;
 287                                 } else {
 288                                         (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 289                                             "SIOCGLIFDSTADDR: %.*s: %s",
 290                                             (int)sizeof(ifrdstaddr.lifr_name),
 291                                             ifrdstaddr.lifr_name,
 292                                             pcap_strerror(errno));
 293                                         ret = -1;
 294                                         break;
 295                                 }
 296                         } else
 297                                 dstaddr = (struct sockaddr *)&ifrdstaddr.lifr_dstaddr;
 298                 } else
 299                         dstaddr = NULL;
 300
 301 #ifdef HAVE_SOLARIS
 302                 /*
 303                  * If this entry has a colon followed by a number at
 304                  * the end, it's a logical interface.  Those are just
 305                  * the way you assign multiple IP addresses to a real
 306                  * interface, so an entry for a logical interface should
 307                  * be treated like the entry for the real interface;
 308                  * we do that by stripping off the ":" and the number.
 309                  */
 310                 p = strchr(ifrp->lifr_name, ':');
 311                 if (p != NULL) {
 312                         /*
 313                          * We have a ":"; is it followed by a number?
 314                          */
 315                         q = p + 1;
 316                         while (isdigit((unsigned char)*q))
 317                                 q++;
 318                         if (*q == '\0') {
 319                                 /*
 320                                  * All digits after the ":" until the end.
 321                                  * Strip off the ":" and everything after
 322                                  * it.
 323                                  */
 324                                 *p = '\0';
 325                         }
 326                 }
 327 #endif
 328
 329                 /*
 330                  * Add information for this address to the list.
 331                  */
 332                 if (add_addr_to_iflist(&devlist, ifrp->lifr_name,
 333                     if_flags_to_pcap_flags(ifrp->lifr_name, ifrflags.lifr_flags),
 334                     (struct sockaddr *)&ifrp->lifr_addr,
 335                     sizeof (struct sockaddr_storage),
 336                     netmask, sizeof (struct sockaddr_storage),
 337                     broadaddr, sizeof (struct sockaddr_storage),
 338                     dstaddr, sizeof (struct sockaddr_storage), errbuf) < 0) {
 339                         ret = -1;
 340                         break;
 341                 }
 342         }
 343         free(buf);
 344         (void)close(fd6);
 345         (void)close(fd4);
 346
 347         if (ret == -1) {
 348                 /*
 349                  * We had an error; free the list we've been constructing.
 350                  */
 351                 if (devlist != NULL) {
 352                         pcap_freealldevs(devlist);
 353                         devlist = NULL;
 354                 }
 355         }
 356
 357         *alldevsp = devlist;
 358         return (ret);
 359 }