components/ip.c

   1 /* See LICENSE file for copyright and license details. */
   2 #include <errno.h>
   3 #include <ifaddrs.h>
   4 #include <netdb.h>
   5 #include <stdio.h>
   6 #include <string.h>
   7 #if defined(__OpenBSD__)
   8         #include <sys/types.h>
   9         #include <sys/socket.h>
  10 #endif
  11
  12 #include "../util.h"
  13
  14 const char *
  15 ipv4(const char *iface)
  16 {
  17         struct ifaddrs *ifaddr, *ifa;
  18         int s;
  19         char host[NI_MAXHOST];
  20
  21         if (getifaddrs(&ifaddr) < 0) {
  22                 fprintf(stderr, "getifaddrs: %s\n", strerror(errno));
  23                 return NULL;
  24         }
  25
  26         for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
  27                 if (!ifa->ifa_addr) {
  28                         continue;
  29                 }
  30                 s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in), host,
  31                                 NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
  32                 if (!strcmp(ifa->ifa_name, iface) &&
  33                     (ifa->ifa_addr->sa_family == AF_INET)) {
  34                         if (s != 0) {
  35                                 fprintf(stderr, "getnameinfo: %s\n", gai_strerror(s));
  36                                 return NULL;
  37                         }
  38                         return bprintf("%s", host);
  39                 }
  40         }
  41
  42         freeifaddrs(ifaddr);
  43
  44         return NULL;
  45 }
  46
  47 const char *
  48 ipv6(const char *iface)
  49 {
  50         struct ifaddrs *ifaddr, *ifa;
  51         int s;
  52         char host[NI_MAXHOST];
  53
  54         if (getifaddrs(&ifaddr) < 0) {
  55                 fprintf(stderr, "getifaddrs: %s\n", strerror(errno));
  56                 return NULL;
  57         }
  58
  59         for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
  60                 if (!ifa->ifa_addr) {
  61                         continue;
  62                 }
  63                 s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in6), host,
  64                                 NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
  65                 if (!strcmp(ifa->ifa_name, iface) &&
  66                     (ifa->ifa_addr->sa_family == AF_INET6)) {
  67                         if (s != 0) {
  68                                 fprintf(stderr, "getnameinfo: %s\n", gai_strerror(s));
  69                                 return NULL;
  70                         }
  71                         return bprintf("%s", host);
  72                 }
  73         }
  74
  75         freeifaddrs(ifaddr);
  76
  77         return NULL;
  78 }