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 4194304
  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
 135         while (needed <= MEMORY_MAX)
 136         {
 137                 buf = malloc(needed);
 138                 if (buf == NULL) return (-1);
 139
 140                 status = sysctl(mib, 6, buf, &needed, NULL, 0);
 141                 if (status >= 0) break;
 142
 143                 free(buf);
 144                 buf = NULL;
 145                 needed *= 2;
 146         }
 147
 148         for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
 149                 rtm = (struct rt_msghdr *)next;
 150                 if (rtm->rtm_version != RTM_VERSION)
 151                         continue;
 152                 switch (rtm->rtm_type) {
 153                 case RTM_IFINFO:
 154                         ifm = (struct if_msghdr *)rtm;
 155                         if (ifm->ifm_addrs & RTA_IFP) {
 156                                 index = ifm->ifm_index;
 157                                 ++icnt;
 158                                 dl = (struct sockaddr_dl *)(ifm + 1);
 159                                 dcnt += SA_RLEN((struct sockaddr *)dl) +
 160                                         ALIGNBYTES;
 161 #ifdef  HAVE_IFM_DATA
 162                                 dcnt += sizeof(ifm->ifm_data);
 163 #endif  /* HAVE_IFM_DATA */
 164                                 ncnt += dl->sdl_nlen + 1;
 165                         } else
 166                                 index = 0;
 167                         break;
 168
 169                 case RTM_NEWADDR:
 170                         ifam = (struct ifa_msghdr *)rtm;
 171                         if (index && ifam->ifam_index != index)
 172                                 abort();        /* this cannot happen */
 173
 174 #define RTA_MASKS       (RTA_NETMASK | RTA_IFA | RTA_BRD)
 175                         if (index == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0)
 176                                 break;
 177                         p = (char *)(ifam + 1);
 178                         ++icnt;
 179 #ifdef  HAVE_IFAM_DATA
 180                         dcnt += sizeof(ifam->ifam_data) + ALIGNBYTES;
 181 #endif  /* HAVE_IFAM_DATA */
 182                         /* Scan to look for length of address */
 183                         alen = 0;
 184                         for (p0 = p, i = 0; i < RTAX_MAX; i++) {
 185                                 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
 186                                     == 0)
 187                                         continue;
 188                                 sa = (struct sockaddr *)p;
 189                                 len = SA_RLEN(sa);
 190                                 if (i == RTAX_IFA) {
 191                                         alen = len;
 192                                         break;
 193                                 }
 194                                 p += len;
 195                         }
 196                         for (p = p0, i = 0; i < RTAX_MAX; i++) {
 197                                 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
 198                                     == 0)
 199                                         continue;
 200                                 sa = (struct sockaddr *)p;
 201                                 len = SA_RLEN(sa);
 202                                 if (i == RTAX_NETMASK && SA_LEN(sa) == 0)
 203                                         dcnt += alen;
 204                                 else
 205                                         dcnt += len;
 206                                 p += len;
 207                         }
 208                         break;
 209                 }
 210         }
 211 #else   /* NET_RT_IFLIST */
 212         ifc.ifc_buf = buf;
 213         ifc.ifc_len = sizeof(buf);
 214
 215         if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
 216                 free(buf);
 217                 return (-1);
 218         }
 219
 220         i =  ioctl(sock, SIOCGIFCONF, (char *)&ifc);
 221         close(sock);
 222         if (i < 0) {
 223                 free(buf);
 224                 return (-1);
 225         }
 226
 227         ifr = ifc.ifc_req;
 228         lifr = (struct ifreq *)&ifc.ifc_buf[ifc.ifc_len];
 229
 230         while (ifr < lifr) {
 231                 struct sockaddr *sa;
 232
 233                 sa = &ifr->ifr_addr;
 234                 ++icnt;
 235                 dcnt += SA_RLEN(sa);
 236                 ncnt += sizeof(ifr->ifr_name) + 1;
 237
 238                 ifr = (struct ifreq *)(((char *)sa) + SA_LEN(sa));
 239         }
 240 #endif  /* NET_RT_IFLIST */
 241
 242         if (icnt + dcnt + ncnt == 1) {
 243                 *pif = NULL;
 244                 free(buf);
 245                 return (0);
 246         }
 247         data = malloc(sizeof(struct ifaddrs) * icnt + dcnt + ncnt);
 248         if (data == NULL) {
 249                 free(buf);
 250                 return(-1);
 251         }
 252
 253         ifa = (struct ifaddrs *)data;
 254         data += sizeof(struct ifaddrs) * icnt;
 255         names = data + dcnt;
 256
 257         memset(ifa, 0, sizeof(struct ifaddrs) * icnt);
 258         ift = ifa;
 259
 260 #ifdef  NET_RT_IFLIST
 261         index = 0;
 262         for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
 263                 rtm = (struct rt_msghdr *)next;
 264                 if (rtm->rtm_version != RTM_VERSION)
 265                         continue;
 266                 switch (rtm->rtm_type) {
 267                 case RTM_IFINFO:
 268                         ifm = (struct if_msghdr *)rtm;
 269                         if (ifm->ifm_addrs & RTA_IFP) {
 270                                 index = ifm->ifm_index;
 271                                 dl = (struct sockaddr_dl *)(ifm + 1);
 272
 273                                 cif = ift;
 274                                 ift->ifa_name = names;
 275                                 ift->ifa_flags = (int)ifm->ifm_flags;
 276                                 memcpy(names, dl->sdl_data, dl->sdl_nlen);
 277                                 names[dl->sdl_nlen] = 0;
 278                                 names += dl->sdl_nlen + 1;
 279
 280                                 ift->ifa_addr = (struct sockaddr *)data;
 281                                 memcpy(data, dl, SA_LEN((struct sockaddr *)dl));
 282                                 data += SA_RLEN((struct sockaddr *)dl);
 283
 284 #ifdef  HAVE_IFM_DATA
 285                                 /* ifm_data needs to be aligned */
 286                                 ift->ifa_data = data = (void *)ALIGN(data);
 287                                 memcpy(data, &ifm->ifm_data, sizeof(ifm->ifm_data));
 288                                 data += sizeof(ifm->ifm_data);
 289 #else   /* HAVE_IFM_DATA */
 290                                 ift->ifa_data = NULL;
 291 #endif  /* HAVE_IFM_DATA */
 292
 293                                 ift = (ift->ifa_next = ift + 1);
 294                         } else
 295                                 index = 0;
 296                         break;
 297
 298                 case RTM_NEWADDR:
 299                         ifam = (struct ifa_msghdr *)rtm;
 300                         if (index && ifam->ifam_index != index)
 301                                 abort();        /* this cannot happen */
 302
 303                         if (index == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0)
 304                                 break;
 305                         ift->ifa_name = cif->ifa_name;
 306                         ift->ifa_flags = cif->ifa_flags;
 307                         ift->ifa_data = NULL;
 308                         p = (char *)(ifam + 1);
 309                         /* Scan to look for length of address */
 310                         alen = 0;
 311                         for (p0 = p, i = 0; i < RTAX_MAX; i++) {
 312                                 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
 313                                     == 0)
 314                                         continue;
 315                                 sa = (struct sockaddr *)p;
 316                                 len = SA_RLEN(sa);
 317                                 if (i == RTAX_IFA) {
 318                                         alen = len;
 319                                         break;
 320                                 }
 321                                 p += len;
 322                         }
 323                         for (p = p0, i = 0; i < RTAX_MAX; i++) {
 324                                 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
 325                                     == 0)
 326                                         continue;
 327                                 sa = (struct sockaddr *)p;
 328                                 len = SA_RLEN(sa);
 329                                 switch (i) {
 330                                 case RTAX_IFA:
 331                                         ift->ifa_addr = (struct sockaddr *)data;
 332                                         memcpy(data, p, len);
 333                                         data += len;
 334                                         break;
 335
 336                                 case RTAX_NETMASK:
 337                                         ift->ifa_netmask =
 338                                             (struct sockaddr *)data;
 339                                         if (SA_LEN(sa) == 0) {
 340                                                 memset(data, 0, alen);
 341                                                 data += alen;
 342                                                 break;
 343                                         }
 344                                         memcpy(data, p, len);
 345                                         data += len;
 346                                         break;
 347
 348                                 case RTAX_BRD:
 349                                         ift->ifa_broadaddr =
 350                                             (struct sockaddr *)data;
 351                                         memcpy(data, p, len);
 352                                         data += len;
 353                                         break;
 354                                 }
 355                                 p += len;
 356                         }
 357
 358 #ifdef  HAVE_IFAM_DATA
 359                         /* ifam_data needs to be aligned */
 360                         ift->ifa_data = data = (void *)ALIGN(data);
 361                         memcpy(data, &ifam->ifam_data, sizeof(ifam->ifam_data));
 362                         data += sizeof(ifam->ifam_data);
 363 #endif  /* HAVE_IFAM_DATA */
 364
 365                         ift = (ift->ifa_next = ift + 1);
 366                         break;
 367                 }
 368         }
 369
 370         free(buf);
 371 #else   /* NET_RT_IFLIST */
 372         ifr = ifc.ifc_req;
 373         lifr = (struct ifreq *)&ifc.ifc_buf[ifc.ifc_len];
 374
 375         while (ifr < lifr) {
 376                 struct sockaddr *sa;
 377
 378                 ift->ifa_name = names;
 379                 names[sizeof(ifr->ifr_name)] = 0;
 380                 strncpy(names, ifr->ifr_name, sizeof(ifr->ifr_name));
 381                 while (*names++)
 382                         ;
 383
 384                 ift->ifa_addr = (struct sockaddr *)data;
 385                 sa = &ifr->ifr_addr;
 386                 memcpy(data, sa, SA_LEN(sa));
 387                 data += SA_RLEN(sa);
 388
 389                 ifr = (struct ifreq *)(((char *)sa) + SA_LEN(sa));
 390                 ift = (ift->ifa_next = ift + 1);
 391         }
 392 #endif  /* NET_RT_IFLIST */
 393         if (--ift >= ifa) {
 394                 ift->ifa_next = NULL;
 395                 *pif = ifa;
 396         } else {
 397                 *pif = NULL;
 398                 free(ifa);
 399         }
 400
 401         for (ift = ifa; ift != NULL; ift = ift->ifa_next)
 402         {
 403                 if (ift->ifa_addr->sa_family == AF_INET6)
 404                 {
 405                         sin6 = (struct sockaddr_in6 *)ift->ifa_addr;
 406                         if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) || IN6_IS_ADDR_SITELOCAL(&sin6->sin6_addr))
 407                         {
 408                                 esid = ntohs(sin6->sin6_addr.__u6_addr.__u6_addr16[1]);
 409                                 sin6->sin6_addr.__u6_addr.__u6_addr16[1] = 0;
 410                                 if (sin6->sin6_scope_id == 0) sin6->sin6_scope_id = esid;
 411                         }
 412                 }
 413         }
 414
 415         return (0);
 416 }
 417
 418 void
 419 freeifaddrs(struct ifaddrs *ifp)
 420 {
 421         free(ifp);
 422 }