The Tcpdump Group git mirrors - libpcap/blob - 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_list_t *devlistp, char *errbuf,
  79     int (*check_usable)(const char *), get_if_flags_func get_flags_func)
  80 {
  81         register int fd4, fd6, fd;
  82         register struct lifreq *ifrp, *ifend;
  83         struct lifnum ifn;
  84         struct lifconf ifc;
  85         char *buf = NULL;
  86         unsigned buf_size;
  87 #ifdef HAVE_SOLARIS
  88         char *p, *q;
  89 #endif
  90         struct lifreq ifrflags, ifrnetmask, ifrbroadaddr, ifrdstaddr;
  91         struct sockaddr *netmask, *broadaddr, *dstaddr;
  92         int ret = 0;
  93
  94         /*
  95          * Create a socket from which to fetch the list of interfaces,
  96          * and from which to fetch IPv4 information.
  97          */
  98         fd4 = socket(AF_INET, SOCK_DGRAM, 0);
  99         if (fd4 < 0) {
 100                 pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
 101                     errno, "socket: AF_INET");
 102                 return (-1);
 103         }
 104
 105         /*
 106          * Create a socket from which to fetch IPv6 information.
 107          */
 108         fd6 = socket(AF_INET6, SOCK_DGRAM, 0);
 109         if (fd6 < 0) {
 110                 pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
 111                     errno, "socket: AF_INET6");
 112                 (void)close(fd4);
 113                 return (-1);
 114         }
 115
 116         /*
 117          * How many entries will SIOCGLIFCONF return?
 118          */
 119         ifn.lifn_family = AF_UNSPEC;
 120         ifn.lifn_flags = 0;
 121         ifn.lifn_count = 0;
 122         if (ioctl(fd4, SIOCGLIFNUM, (char *)&ifn) < 0) {
 123                 pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
 124                     errno, "SIOCGLIFNUM");
 125                 (void)close(fd6);
 126                 (void)close(fd4);
 127                 return (-1);
 128         }
 129
 130         /*
 131          * Allocate a buffer for those entries.
 132          */
 133         buf_size = ifn.lifn_count * sizeof (struct lifreq);
 134         buf = malloc(buf_size);
 135         if (buf == NULL) {
 136                 pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
 137                     errno, "malloc");
 138                 (void)close(fd6);
 139                 (void)close(fd4);
 140                 return (-1);
 141         }
 142
 143         /*
 144          * Get the entries.
 145          */
 146         ifc.lifc_len = buf_size;
 147         ifc.lifc_buf = buf;
 148         ifc.lifc_family = AF_UNSPEC;
 149         ifc.lifc_flags = 0;
 150         memset(buf, 0, buf_size);
 151         if (ioctl(fd4, SIOCGLIFCONF, (char *)&ifc) < 0) {
 152                 pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
 153                     errno, "SIOCGLIFCONF");
 154                 (void)close(fd6);
 155                 (void)close(fd4);
 156                 free(buf);
 157                 return (-1);
 158         }
 159
 160         /*
 161          * Loop over the entries.
 162          */
 163         ifrp = (struct lifreq *)buf;
 164         ifend = (struct lifreq *)(buf + ifc.lifc_len);
 165
 166         for (; ifrp < ifend; ifrp++) {
 167                 /*
 168                  * Skip entries that begin with "dummy".
 169                  * XXX - what are these?  Is this Linux-specific?
 170                  * Are there platforms on which we shouldn't do this?
 171                  */
 172                 if (strncmp(ifrp->lifr_name, "dummy", 5) == 0)
 173                         continue;
 174
 175                 /*
 176                  * Can we capture on this device?
 177                  */
 178                 if (!(*check_usable)(ifrp->lifr_name)) {
 179                         /*
 180                          * No.
 181                          */
 182                         continue;
 183                 }
 184
 185                 /*
 186                  * IPv6 or not?
 187                  */
 188                 if (((struct sockaddr *)&ifrp->lifr_addr)->sa_family == AF_INET6)
 189                         fd = fd6;
 190                 else
 191                         fd = fd4;
 192
 193                 /*
 194                  * Get the flags for this interface.
 195                  */
 196                 strncpy(ifrflags.lifr_name, ifrp->lifr_name,
 197                     sizeof(ifrflags.lifr_name));
 198                 if (ioctl(fd, SIOCGLIFFLAGS, (char *)&ifrflags) < 0) {
 199                         if (errno == ENXIO)
 200                                 continue;
 201                         pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
 202                             errno, "SIOCGLIFFLAGS: %.*s",
 203                             (int)sizeof(ifrflags.lifr_name),
 204                             ifrflags.lifr_name);
 205                         ret = -1;
 206                         break;
 207                 }
 208
 209                 /*
 210                  * Get the netmask for this address on this interface.
 211                  */
 212                 strncpy(ifrnetmask.lifr_name, ifrp->lifr_name,
 213                     sizeof(ifrnetmask.lifr_name));
 214                 memcpy(&ifrnetmask.lifr_addr, &ifrp->lifr_addr,
 215                     sizeof(ifrnetmask.lifr_addr));
 216                 if (ioctl(fd, SIOCGLIFNETMASK, (char *)&ifrnetmask) < 0) {
 217                         if (errno == EADDRNOTAVAIL) {
 218                                 /*
 219                                  * Not available.
 220                                  */
 221                                 netmask = NULL;
 222                         } else {
 223                                 pcap_fmt_errmsg_for_errno(errbuf,
 224                                     PCAP_ERRBUF_SIZE, errno,
 225                                     "SIOCGLIFNETMASK: %.*s",
 226                                     (int)sizeof(ifrnetmask.lifr_name),
 227                                     ifrnetmask.lifr_name);
 228                                 ret = -1;
 229                                 break;
 230                         }
 231                 } else
 232                         netmask = (struct sockaddr *)&ifrnetmask.lifr_addr;
 233
 234                 /*
 235                  * Get the broadcast address for this address on this
 236                  * interface (if any).
 237                  */
 238                 if (ifrflags.lifr_flags & IFF_BROADCAST) {
 239                         strncpy(ifrbroadaddr.lifr_name, ifrp->lifr_name,
 240                             sizeof(ifrbroadaddr.lifr_name));
 241                         memcpy(&ifrbroadaddr.lifr_addr, &ifrp->lifr_addr,
 242                             sizeof(ifrbroadaddr.lifr_addr));
 243                         if (ioctl(fd, SIOCGLIFBRDADDR,
 244                             (char *)&ifrbroadaddr) < 0) {
 245                                 if (errno == EADDRNOTAVAIL) {
 246                                         /*
 247                                          * Not available.
 248                                          */
 249                                         broadaddr = NULL;
 250                                 } else {
 251                                         pcap_fmt_errmsg_for_errno(errbuf,
 252                                             PCAP_ERRBUF_SIZE, errno,
 253                                             "SIOCGLIFBRDADDR: %.*s",
 254                                             (int)sizeof(ifrbroadaddr.lifr_name),
 255                                             ifrbroadaddr.lifr_name);
 256                                         ret = -1;
 257                                         break;
 258                                 }
 259                         } else
 260                                 broadaddr = (struct sockaddr *)&ifrbroadaddr.lifr_broadaddr;
 261                 } else {
 262                         /*
 263                          * Not a broadcast interface, so no broadcast
 264                          * address.
 265                          */
 266                         broadaddr = NULL;
 267                 }
 268
 269                 /*
 270                  * Get the destination address for this address on this
 271                  * interface (if any).
 272                  */
 273                 if (ifrflags.lifr_flags & IFF_POINTOPOINT) {
 274                         strncpy(ifrdstaddr.lifr_name, ifrp->lifr_name,
 275                             sizeof(ifrdstaddr.lifr_name));
 276                         memcpy(&ifrdstaddr.lifr_addr, &ifrp->lifr_addr,
 277                             sizeof(ifrdstaddr.lifr_addr));
 278                         if (ioctl(fd, SIOCGLIFDSTADDR,
 279                             (char *)&ifrdstaddr) < 0) {
 280                                 if (errno == EADDRNOTAVAIL) {
 281                                         /*
 282                                          * Not available.
 283                                          */
 284                                         dstaddr = NULL;
 285                                 } else {
 286                                         pcap_fmt_errmsg_for_errno(errbuf,
 287                                             PCAP_ERRBUF_SIZE, errno,
 288                                             "SIOCGLIFDSTADDR: %.*s",
 289                                             (int)sizeof(ifrdstaddr.lifr_name),
 290                                             ifrdstaddr.lifr_name);
 291                                         ret = -1;
 292                                         break;
 293                                 }
 294                         } else
 295                                 dstaddr = (struct sockaddr *)&ifrdstaddr.lifr_dstaddr;
 296                 } else
 297                         dstaddr = NULL;
 298
 299 #ifdef HAVE_SOLARIS
 300                 /*
 301                  * If this entry has a colon followed by a number at
 302                  * the end, it's a logical interface.  Those are just
 303                  * the way you assign multiple IP addresses to a real
 304                  * interface, so an entry for a logical interface should
 305                  * be treated like the entry for the real interface;
 306                  * we do that by stripping off the ":" and the number.
 307                  */
 308                 p = strchr(ifrp->lifr_name, ':');
 309                 if (p != NULL) {
 310                         /*
 311                          * We have a ":"; is it followed by a number?
 312                          */
 313                         q = p + 1;
 314                         while (isdigit((unsigned char)*q))
 315                                 q++;
 316                         if (*q == '\0') {
 317                                 /*
 318                                  * All digits after the ":" until the end.
 319                                  * Strip off the ":" and everything after
 320                                  * it.
 321                                  */
 322                                 *p = '\0';
 323                         }
 324                 }
 325 #endif
 326
 327                 /*
 328                  * Add information for this address to the list.
 329                  */
 330                 if (add_addr_to_if(devlistp, ifrp->lifr_name,
 331                     ifrflags.lifr_flags, get_flags_func,
 332                     (struct sockaddr *)&ifrp->lifr_addr,
 333                     sizeof (struct sockaddr_storage),
 334                     netmask, sizeof (struct sockaddr_storage),
 335                     broadaddr, sizeof (struct sockaddr_storage),
 336                     dstaddr, sizeof (struct sockaddr_storage), errbuf) < 0) {
 337                         ret = -1;
 338                         break;
 339                 }
 340         }
 341         free(buf);
 342         (void)close(fd6);
 343         (void)close(fd4);
 344
 345         return (ret);
 346 }