ip.c

   1 /* See LICENSE file for copyright and license details. */
   2 #include <err.h>
   3 #include <ifaddrs.h>
   4 #include <netdb.h>
   5 #include <stdio.h>
   6 #include <string.h>
   7
   8 #include "util.h"
   9
  10 const char *
  11 ipv4(const char *iface)
  12 {
  13         struct ifaddrs *ifaddr, *ifa;
  14         int s;
  15         char host[NI_MAXHOST];
  16
  17         if (getifaddrs(&ifaddr) == -1) {
  18                 warn("Failed to get IPv4 address for interface %s", iface);
  19                 return NULL;
  20         }
  21
  22         for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
  23                 if (ifa->ifa_addr == NULL) {
  24                         continue;
  25                 }
  26                 s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in), host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
  27                 if ((strcmp(ifa->ifa_name, iface) == 0) && (ifa->ifa_addr->sa_family == AF_INET)) {
  28                         if (s != 0) {
  29                                 warnx("Failed to get IPv4 address for interface %s", iface);
  30                                 return NULL;
  31                         }
  32                         return bprintf("%s", host);
  33                 }
  34         }
  35
  36         freeifaddrs(ifaddr);
  37
  38         return NULL;
  39 }
  40
  41 const char *
  42 ipv6(const char *iface)
  43 {
  44         struct ifaddrs *ifaddr, *ifa;
  45         int s;
  46         char host[NI_MAXHOST];
  47
  48         if (getifaddrs(&ifaddr) == -1) {
  49                 warn("Failed to get IPv6 address for interface %s", iface);
  50                 return NULL;
  51         }
  52
  53         for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
  54                 if (ifa->ifa_addr == NULL) {
  55                         continue;
  56                 }
  57                 s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in6), host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
  58                 if ((strcmp(ifa->ifa_name, iface) == 0) && (ifa->ifa_addr->sa_family == AF_INET6)) {
  59                         if (s != 0) {
  60                                 warnx("Failed to get IPv6 address for interface %s", iface);
  61                                 return NULL;
  62                         }
  63                         return bprintf("%s", host);
  64                 }
  65         }
  66
  67         freeifaddrs(ifaddr);
  68
  69         return NULL;
  70 }