lib/getifaddrs.c

   1 /*
   2  * downloaded from
   3  * http://ftp.uninett.no/pub/OpenBSD/src/kerberosV/src/lib/roken/getifaddrs.c
   4  */
   5 #if !HAVE_GETIFADDRS
   6 /*
   7  * Copyright (c) 2000 - 2001 Kungliga Tekniska H�gskolan
   8  * (Royal Institute of Technology, Stockholm, Sweden).
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  *
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  *
  18  * 2. Redistributions in binary form must reproduce the above copyright
  19  *    notice, this list of conditions and the following disclaimer in the
  20  *    documentation and/or other materials provided with the distribution.
  21  *
  22  * 3. Neither the name of the Institute nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  */
  38
  39 #include <errno.h>
  40 #include <sys/types.h>
  41 #include <sys/socket.h>
  42 #include <net/if.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <sys/ioctl.h>
  46 #include <unistd.h>
  47 #include "private-libwebsockets.h"
  48
  49 #ifdef HAVE_SYS_SOCKIO_H
  50 #include <sys/sockio.h>
  51 #endif
  52
  53 #ifdef HAVE_NETINET_IN6_VAR_H
  54 #include <netinet/in6_var.h>
  55 #endif
  56
  57 #ifndef max
  58 #define max(a, b) ((a) > (b) ? (a) : (b))
  59 #endif
  60
  61 #include "getifaddrs.h"
  62
  63 static int
  64 getifaddrs2(struct ifaddrs **ifap,
  65             int af, int siocgifconf, int siocgifflags,
  66             size_t ifreq_sz)
  67 {
  68         int ret;
  69         int fd;
  70         size_t buf_size;
  71         char *buf;
  72         struct ifconf ifconf;
  73         char *p;
  74         size_t sz;
  75         struct sockaddr sa_zero;
  76         struct ifreq *ifr;
  77
  78         struct ifaddrs *start,  **end = &start;
  79
  80         buf = NULL;
  81
  82         memset(&sa_zero, 0, sizeof(sa_zero));
  83         fd = socket(af, SOCK_DGRAM, 0);
  84         if (fd < 0)
  85                 return -1;
  86
  87         buf_size = 8192;
  88         for (;;) {
  89                 buf = lws_zalloc(buf_size);
  90                 if (buf == NULL) {
  91                         ret = ENOMEM;
  92                         goto error_out;
  93                 }
  94                 ifconf.ifc_len = buf_size;
  95                 ifconf.ifc_buf = buf;
  96
  97                 /*
  98                  * Solaris returns EINVAL when the buffer is too small.
  99                  */
 100                 if (ioctl(fd, siocgifconf, &ifconf) < 0 && errno != EINVAL) {
 101                         ret = errno;
 102                         goto error_out;
 103                 }
 104                 /*
 105                  * Can the difference between a full and a overfull buf
 106                  * be determined?
 107                  */
 108
 109                 if (ifconf.ifc_len < (int)buf_size)
 110                         break;
 111                 lws_free(buf);
 112                 buf_size *= 2;
 113         }
 114
 115         for (p = ifconf.ifc_buf; p < ifconf.ifc_buf + ifconf.ifc_len; p += sz) {
 116                 struct ifreq ifreq;
 117                 struct sockaddr *sa;
 118                 size_t salen;
 119
 120                 ifr = (struct ifreq *)p;
 121                 sa  = &ifr->ifr_addr;
 122
 123                 sz = ifreq_sz;
 124                 salen = sizeof(struct sockaddr);
 125 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 126                 salen = sa->sa_len;
 127                 sz = max(sz, sizeof(ifr->ifr_name) + sa->sa_len);
 128 #endif
 129 #ifdef SA_LEN
 130                 salen = SA_LEN(sa);
 131                 sz = max(sz, sizeof(ifr->ifr_name) + SA_LEN(sa));
 132 #endif
 133                 memset(&ifreq, 0, sizeof(ifreq));
 134                 memcpy(ifreq.ifr_name, ifr->ifr_name, sizeof(ifr->ifr_name));
 135
 136                 if (ioctl(fd, siocgifflags, &ifreq) < 0) {
 137                         ret = errno;
 138                         goto error_out;
 139                 }
 140
 141                 *end = lws_malloc(sizeof(**end));
 142
 143                 (*end)->ifa_next = NULL;
 144                 (*end)->ifa_name = strdup(ifr->ifr_name);
 145                 (*end)->ifa_flags = ifreq.ifr_flags;
 146                 (*end)->ifa_addr = lws_malloc(salen);
 147                 memcpy((*end)->ifa_addr, sa, salen);
 148                 (*end)->ifa_netmask = NULL;
 149
 150 #if 0
 151                 /* fix these when we actually need them */
 152                 if (ifreq.ifr_flags & IFF_BROADCAST) {
 153                         (*end)->ifa_broadaddr =
 154                                 lws_malloc(sizeof(ifr->ifr_broadaddr));
 155                         memcpy((*end)->ifa_broadaddr, &ifr->ifr_broadaddr,
 156                                                     sizeof(ifr->ifr_broadaddr));
 157                 } else if (ifreq.ifr_flags & IFF_POINTOPOINT) {
 158                         (*end)->ifa_dstaddr =
 159                                 lws_malloc(sizeof(ifr->ifr_dstaddr));
 160                         memcpy((*end)->ifa_dstaddr, &ifr->ifr_dstaddr,
 161                                                       sizeof(ifr->ifr_dstaddr));
 162                 } else
 163                         (*end)->ifa_dstaddr = NULL;
 164 #else
 165                 (*end)->ifa_dstaddr = NULL;
 166 #endif
 167                 (*end)->ifa_data = NULL;
 168
 169                 end = &(*end)->ifa_next;
 170
 171         }
 172         *ifap = start;
 173         close(fd);
 174         lws_free(buf);
 175         return 0;
 176
 177 error_out:
 178         close(fd);
 179         lws_free(buf);
 180         errno = ret;
 181
 182         return -1;
 183 }
 184
 185 int
 186 getifaddrs(struct ifaddrs **ifap)
 187 {
 188         int ret = -1;
 189         errno = ENXIO;
 190 #if defined(AF_INET6) && defined(SIOCGIF6CONF) && defined(SIOCGIF6FLAGS)
 191         if (ret)
 192                 ret = getifaddrs2(ifap, AF_INET6, SIOCGIF6CONF, SIOCGIF6FLAGS,
 193                            sizeof(struct in6_ifreq));
 194 #endif
 195 #if defined(HAVE_IPV6) && defined(SIOCGIFCONF)
 196         if (ret)
 197                 ret = getifaddrs2(ifap, AF_INET6, SIOCGIFCONF, SIOCGIFFLAGS,
 198                            sizeof(struct ifreq));
 199 #endif
 200 #if defined(AF_INET) && defined(SIOCGIFCONF) && defined(SIOCGIFFLAGS)
 201         if (ret)
 202                 ret = getifaddrs2(ifap, AF_INET, SIOCGIFCONF, SIOCGIFFLAGS,
 203                            sizeof(struct ifreq));
 204 #endif
 205         return ret;
 206 }
 207
 208 void
 209 freeifaddrs(struct ifaddrs *ifp)
 210 {
 211         struct ifaddrs *p, *q;
 212
 213         for (p = ifp; p; ) {
 214                 lws_free(p->ifa_name);
 215                 lws_free(p->ifa_addr);
 216                 lws_free(p->ifa_dstaddr);
 217                 lws_free(p->ifa_netmask);
 218                 lws_free(p->ifa_data);
 219                 q = p;
 220                 p = p->ifa_next;
 221                 lws_free(q);
 222         }
 223 }
 224
 225 #ifdef TEST
 226
 227 void
 228 print_addr(const char *s, struct sockaddr *sa)
 229 {
 230         int i;
 231         printf("  %s=%d/", s, sa->sa_family);
 232 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 233         for (i = 0;
 234                i < sa->sa_len - ((long)sa->sa_data - (long)&sa->sa_family); i++)
 235                 printf("%02x", ((unsigned char *)sa->sa_data)[i]);
 236 #else
 237         for (i = 0; i < sizeof(sa->sa_data); i++)
 238                 printf("%02x", ((unsigned char *)sa->sa_data)[i]);
 239 #endif
 240         printf("\n");
 241 }
 242
 243 void
 244 print_ifaddrs(struct ifaddrs *x)
 245 {
 246         struct ifaddrs *p;
 247
 248         for (p = x; p; p = p->ifa_next) {
 249                 printf("%s\n", p->ifa_name);
 250                 printf("  flags=%x\n", p->ifa_flags);
 251                 if (p->ifa_addr)
 252                         print_addr("addr", p->ifa_addr);
 253                 if (p->ifa_dstaddr)
 254                         print_addr("dstaddr", p->ifa_dstaddr);
 255                 if (p->ifa_netmask)
 256                         print_addr("netmask", p->ifa_netmask);
 257                 printf("  %p\n", p->ifa_data);
 258         }
 259 }
 260
 261 int
 262 main()
 263 {
 264         struct ifaddrs *a = NULL, *b;
 265         getifaddrs2(&a, AF_INET, SIOCGIFCONF,
 266                                 SIOCGIFFLAGS, sizeof(struct ifreq));
 267         print_ifaddrs(a);
 268         printf("---\n");
 269         getifaddrs(&b);
 270         print_ifaddrs(b);
 271         return 0;
 272 }
 273 #endif
 274 #endif