gen.subproj/getifaddrs.c

   1 /*
   2  * Copyright (c) 1995, 1999
   3  *      Berkeley Software Design, Inc.  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  *
  11  * THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND
  12  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  13  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  14  * ARE DISCLAIMED.  IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE
  15  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  16  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  17  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  18  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  19  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  20  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  21  * SUCH DAMAGE.
  22  *
  23  *      BSDI getifaddrs.c,v 2.12 2000/02/23 14:51:59 dab Exp
  24  */
  25 /*
  26  * NOTE: SIOCGIFCONF case is not LP64 friendly.  it also does not perform
  27  * try-and-error for region size.
  28  */
  29 #include <sys/types.h>
  30 #include <sys/ioctl.h>
  31 #include <sys/socket.h>
  32 #include <net/if.h>
  33 #ifdef  NET_RT_IFLIST
  34 #include <sys/param.h>
  35 #include <net/route.h>
  36 #include <sys/sysctl.h>
  37 #include <net/if_dl.h>
  38 #endif
  39
  40 #include <errno.h>
  41 #include <ifaddrs.h>
  42 #include <netinet/in.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <stdint.h>
  46
  47 #if !defined(AF_LINK)
  48 #define SA_LEN(sa)      sizeof(struct sockaddr)
  49 #endif
  50
  51 #if !defined(SA_LEN)
  52 #define SA_LEN(sa)      (sa)->sa_len
  53 #endif
  54
  55 #define SALIGN  (sizeof(int32_t) - 1)
  56 #define SA_RLEN(sa)     ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : (SALIGN + 1))
  57
  58 #ifndef ALIGNBYTES
  59 /*
  60  * On systems with a routing socket, ALIGNBYTES should match the value
  61  * that the kernel uses when building the messages.
  62  */
  63 #define ALIGNBYTES      XXX
  64 #endif
  65 #ifndef ALIGN
  66 #define ALIGN(p)        (((u_long)(p) + ALIGNBYTES) &~ ALIGNBYTES)
  67 #endif
  68
  69 #if     _BSDI_VERSION >= 199701
  70 #define HAVE_IFM_DATA
  71 #endif
  72
  73 #if     _BSDI_VERSION >= 199802
  74 /* ifam_data is very specific to recent versions of bsdi */
  75 #define HAVE_IFAM_DATA
  76 #endif
  77
  78 #if defined(__NetBSD__) || defined(__OpenBSD__) || defined(__FreeBSD__)
  79 #define HAVE_IFM_DATA
  80 #endif
  81
  82 #ifdef __APPLE__
  83 #define HAVE_IFM_DATA
  84 #endif
  85
  86 #define MEMORY_MIN 2048
  87 #define MEMORY_MAX 16777216
  88
  89 int
  90 getifaddrs(struct ifaddrs **pif)
  91 {
  92         int icnt = 1;
  93         int dcnt = 0;
  94         int ncnt = 0;
  95         struct ifaddrs *ifa, *ift;
  96         struct sockaddr_in6 *sin6;
  97         uint16_t esid;
  98 #ifdef  NET_RT_IFLIST
  99         int mib[6];
 100         size_t needed;
 101         char *buf;
 102         char *next;
 103         struct ifaddrs *cif = 0;
 104         char *p, *p0;
 105         struct rt_msghdr *rtm;
 106         struct if_msghdr *ifm;
 107         struct ifa_msghdr *ifam;
 108         struct sockaddr_dl *dl;
 109         struct sockaddr *sa;
 110         u_short index = 0;
 111 #else   /* NET_RT_IFLIST */
 112         char buf[1024];
 113         int m, sock;
 114         struct ifconf ifc;
 115         struct ifreq *ifr;
 116         struct ifreq *lifr;
 117 #endif  /* NET_RT_IFLIST */
 118         int i, status;
 119         size_t len, alen;
 120         char *data;
 121         char *names;
 122
 123 #ifdef  NET_RT_IFLIST
 124         mib[0] = CTL_NET;
 125         mib[1] = PF_ROUTE;
 126         mib[2] = 0;             /* protocol */
 127         mib[3] = 0;             /* wildcard address family */
 128         mib[4] = NET_RT_IFLIST;
 129         mib[5] = 0;             /* no flags */
 130         if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) return (-1);
 131
 132         if (needed < MEMORY_MIN) needed = MEMORY_MIN;
 133         needed *= 2;
 134         if (needed > MEMORY_MAX) needed = MEMORY_MAX;
 135
 136         buf = NULL;
 137
 138         while (needed <= MEMORY_MAX)
 139         {
 140                 buf = malloc(needed);
 141                 if (buf == NULL) return (-1);
 142
 143                 status = sysctl(mib, 6, buf, &needed, NULL, 0);
 144                 if (status >= 0) break;
 145
 146                 free(buf);
 147                 buf = NULL;
 148                 needed *= 2;
 149         }
 150
 151         if (buf == NULL)
 152         {
 153                 errno = ENOBUFS;
 154                 return (-1);
 155         }
 156
 157         for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
 158                 rtm = (struct rt_msghdr *)next;
 159                 if (rtm->rtm_version != RTM_VERSION)
 160                         continue;
 161                 switch (rtm->rtm_type) {
 162                 case RTM_IFINFO:
 163                         ifm = (struct if_msghdr *)rtm;
 164                         if (ifm->ifm_addrs & RTA_IFP) {
 165                                 index = ifm->ifm_index;
 166                                 ++icnt;
 167                                 dl = (struct sockaddr_dl *)(ifm + 1);
 168                                 dcnt += SA_RLEN((struct sockaddr *)dl) +
 169                                         ALIGNBYTES;
 170 #ifdef  HAVE_IFM_DATA
 171                                 dcnt += sizeof(ifm->ifm_data);
 172 #endif  /* HAVE_IFM_DATA */
 173                                 ncnt += dl->sdl_nlen + 1;
 174                         } else
 175                                 index = 0;
 176                         break;
 177
 178                 case RTM_NEWADDR:
 179                         ifam = (struct ifa_msghdr *)rtm;
 180                         if (index && ifam->ifam_index != index)
 181                                 abort();        /* this cannot happen */
 182
 183 #define RTA_MASKS       (RTA_NETMASK | RTA_IFA | RTA_BRD)
 184                         if (index == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0)
 185                                 break;
 186                         p = (char *)(ifam + 1);
 187                         ++icnt;
 188 #ifdef  HAVE_IFAM_DATA
 189                         dcnt += sizeof(ifam->ifam_data) + ALIGNBYTES;
 190 #endif  /* HAVE_IFAM_DATA */
 191                         /* Scan to look for length of address */
 192                         alen = 0;
 193                         for (p0 = p, i = 0; i < RTAX_MAX; i++) {
 194                                 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
 195                                     == 0)
 196                                         continue;
 197                                 sa = (struct sockaddr *)p;
 198                                 len = SA_RLEN(sa);
 199                                 if (i == RTAX_IFA) {
 200                                         alen = len;
 201                                         break;
 202                                 }
 203                                 p += len;
 204                         }
 205                         for (p = p0, i = 0; i < RTAX_MAX; i++) {
 206                                 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
 207                                     == 0)
 208                                         continue;
 209                                 sa = (struct sockaddr *)p;
 210                                 len = SA_RLEN(sa);
 211                                 if (i == RTAX_NETMASK && SA_LEN(sa) == 0)
 212                                         dcnt += alen;
 213                                 else
 214                                         dcnt += len;
 215                                 p += len;
 216                         }
 217                         break;
 218                 }
 219         }
 220 #else   /* NET_RT_IFLIST */
 221         ifc.ifc_buf = buf;
 222         ifc.ifc_len = sizeof(buf);
 223
 224         if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
 225                 free(buf);
 226                 return (-1);
 227         }
 228
 229         i =  ioctl(sock, SIOCGIFCONF, (char *)&ifc);
 230         close(sock);
 231         if (i < 0) {
 232                 free(buf);
 233                 return (-1);
 234         }
 235
 236         ifr = ifc.ifc_req;
 237         lifr = (struct ifreq *)&ifc.ifc_buf[ifc.ifc_len];
 238
 239         while (ifr < lifr) {
 240                 struct sockaddr *sa;
 241
 242                 sa = &ifr->ifr_addr;
 243                 ++icnt;
 244                 dcnt += SA_RLEN(sa);
 245                 ncnt += sizeof(ifr->ifr_name) + 1;
 246
 247                 ifr = (struct ifreq *)(((char *)sa) + SA_LEN(sa));
 248         }
 249 #endif  /* NET_RT_IFLIST */
 250
 251         if (icnt + dcnt + ncnt == 1) {
 252                 *pif = NULL;
 253                 free(buf);
 254                 return (0);
 255         }
 256         data = malloc(sizeof(struct ifaddrs) * icnt + dcnt + ncnt);
 257         if (data == NULL) {
 258                 free(buf);
 259                 return(-1);
 260         }
 261
 262         ifa = (struct ifaddrs *)data;
 263         data += sizeof(struct ifaddrs) * icnt;
 264         names = data + dcnt;
 265
 266         memset(ifa, 0, sizeof(struct ifaddrs) * icnt);
 267         ift = ifa;
 268
 269 #ifdef  NET_RT_IFLIST
 270         index = 0;
 271         for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
 272                 rtm = (struct rt_msghdr *)next;
 273                 if (rtm->rtm_version != RTM_VERSION)
 274                         continue;
 275                 switch (rtm->rtm_type) {
 276                 case RTM_IFINFO:
 277                         ifm = (struct if_msghdr *)rtm;
 278                         if (ifm->ifm_addrs & RTA_IFP) {
 279                                 index = ifm->ifm_index;
 280                                 dl = (struct sockaddr_dl *)(ifm + 1);
 281
 282                                 cif = ift;
 283                                 ift->ifa_name = names;
 284                                 ift->ifa_flags = (int)ifm->ifm_flags;
 285                                 memcpy(names, dl->sdl_data, dl->sdl_nlen);
 286                                 names[dl->sdl_nlen] = 0;
 287                                 names += dl->sdl_nlen + 1;
 288
 289                                 ift->ifa_addr = (struct sockaddr *)data;
 290                                 memcpy(data, dl, SA_LEN((struct sockaddr *)dl));
 291                                 data += SA_RLEN((struct sockaddr *)dl);
 292
 293 #ifdef  HAVE_IFM_DATA
 294                                 /* ifm_data needs to be aligned */
 295                                 ift->ifa_data = data = (void *)ALIGN(data);
 296                                 memcpy(data, &ifm->ifm_data, sizeof(ifm->ifm_data));
 297                                 data += sizeof(ifm->ifm_data);
 298 #else   /* HAVE_IFM_DATA */
 299                                 ift->ifa_data = NULL;
 300 #endif  /* HAVE_IFM_DATA */
 301
 302                                 ift = (ift->ifa_next = ift + 1);
 303                         } else
 304                                 index = 0;
 305                         break;
 306
 307                 case RTM_NEWADDR:
 308                         ifam = (struct ifa_msghdr *)rtm;
 309                         if (index && ifam->ifam_index != index)
 310                                 abort();        /* this cannot happen */
 311
 312                         if (index == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0)
 313                                 break;
 314                         ift->ifa_name = cif->ifa_name;
 315                         ift->ifa_flags = cif->ifa_flags;
 316                         ift->ifa_data = NULL;
 317                         p = (char *)(ifam + 1);
 318                         /* Scan to look for length of address */
 319                         alen = 0;
 320                         for (p0 = p, i = 0; i < RTAX_MAX; i++) {
 321                                 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
 322                                     == 0)
 323                                         continue;
 324                                 sa = (struct sockaddr *)p;
 325                                 len = SA_RLEN(sa);
 326                                 if (i == RTAX_IFA) {
 327                                         alen = len;
 328                                         break;
 329                                 }
 330                                 p += len;
 331                         }
 332                         for (p = p0, i = 0; i < RTAX_MAX; i++) {
 333                                 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
 334                                     == 0)
 335                                         continue;
 336                                 sa = (struct sockaddr *)p;
 337                                 len = SA_RLEN(sa);
 338                                 switch (i) {
 339                                 case RTAX_IFA:
 340                                         ift->ifa_addr = (struct sockaddr *)data;
 341                                         memcpy(data, p, len);
 342                                         data += len;
 343                                         break;
 344
 345                                 case RTAX_NETMASK:
 346                                         ift->ifa_netmask =
 347                                             (struct sockaddr *)data;
 348                                         if (SA_LEN(sa) == 0) {
 349                                                 memset(data, 0, alen);
 350                                                 data += alen;
 351                                                 break;
 352                                         }
 353                                         memcpy(data, p, len);
 354                                         data += len;
 355                                         break;
 356
 357                                 case RTAX_BRD:
 358                                         ift->ifa_broadaddr =
 359                                             (struct sockaddr *)data;
 360                                         memcpy(data, p, len);
 361                                         data += len;
 362                                         break;
 363                                 }
 364                                 p += len;
 365                         }
 366
 367 #ifdef  HAVE_IFAM_DATA
 368                         /* ifam_data needs to be aligned */
 369                         ift->ifa_data = data = (void *)ALIGN(data);
 370                         memcpy(data, &ifam->ifam_data, sizeof(ifam->ifam_data));
 371                         data += sizeof(ifam->ifam_data);
 372 #endif  /* HAVE_IFAM_DATA */
 373
 374                         ift = (ift->ifa_next = ift + 1);
 375                         break;
 376                 }
 377         }
 378
 379         free(buf);
 380 #else   /* NET_RT_IFLIST */
 381         ifr = ifc.ifc_req;
 382         lifr = (struct ifreq *)&ifc.ifc_buf[ifc.ifc_len];
 383
 384         while (ifr < lifr) {
 385                 struct sockaddr *sa;
 386
 387                 ift->ifa_name = names;
 388                 names[sizeof(ifr->ifr_name)] = 0;
 389                 strncpy(names, ifr->ifr_name, sizeof(ifr->ifr_name));
 390                 while (*names++)
 391                         ;
 392
 393                 ift->ifa_addr = (struct sockaddr *)data;
 394                 sa = &ifr->ifr_addr;
 395                 memcpy(data, sa, SA_LEN(sa));
 396                 data += SA_RLEN(sa);
 397
 398                 ifr = (struct ifreq *)(((char *)sa) + SA_LEN(sa));
 399                 ift = (ift->ifa_next = ift + 1);
 400         }
 401 #endif  /* NET_RT_IFLIST */
 402         if (--ift >= ifa) {
 403                 ift->ifa_next = NULL;
 404                 *pif = ifa;
 405
 406                 for (ift = ifa; ift != NULL; ift = ift->ifa_next)
 407                 {
 408                         if (ift->ifa_addr->sa_family == AF_INET6)
 409                         {
 410                                 sin6 = (struct sockaddr_in6 *)ift->ifa_addr;
 411                                 if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) || IN6_IS_ADDR_SITELOCAL(&sin6->sin6_addr))
 412                                 {
 413                                         esid = ntohs(sin6->sin6_addr.__u6_addr.__u6_addr16[1]);
 414                                         sin6->sin6_addr.__u6_addr.__u6_addr16[1] = 0;
 415                                         if (sin6->sin6_scope_id == 0) sin6->sin6_scope_id = esid;
 416                                 }
 417                         }
 418                 }
 419         }
 420         else {
 421                 *pif = NULL;
 422                 free(ifa);
 423         }
 424
 425         return (0);
 426 }
 427
 428 void
 429 freeifaddrs(struct ifaddrs *ifp)
 430 {
 431         free(ifp);
 432 }