contrib/ipfilter/lib/hostname.c

   1 /*      $FreeBSD$       */
   2
   3 /*
   4  * Copyright (C) 2012 by Darren Reed.
   5  *
   6  * See the IPFILTER.LICENCE file for details on licencing.
   7  *
   8  * $Id$
   9  */
  10
  11 #include "ipf.h"
  12
  13 char *
  14 hostname(int family, void *ip)
  15 {
  16         static char hostbuf[MAXHOSTNAMELEN+1];
  17         struct hostent *hp;
  18         struct in_addr ipa;
  19         struct netent *np;
  20
  21         memset(&ipa, 0, sizeof(ipa));   /* XXX gcc */
  22
  23         if (family == AF_INET) {
  24                 ipa.s_addr = *(u_32_t *)ip;
  25                 if (ipa.s_addr == htonl(0xfedcba98))
  26                         return ("test.host.dots");
  27         }
  28
  29         if ((opts & OPT_NORESOLVE) == 0) {
  30                 if (family == AF_INET) {
  31                         hp = gethostbyaddr(ip, 4, AF_INET);
  32                         if (hp != NULL && hp->h_name != NULL &&
  33                             *hp->h_name != '\0') {
  34                                 strncpy(hostbuf, hp->h_name, sizeof(hostbuf));
  35                                 hostbuf[sizeof(hostbuf) - 1] = '\0';
  36                                 return (hostbuf);
  37                         }
  38
  39                         np = getnetbyaddr(ipa.s_addr, AF_INET);
  40                         if (np != NULL && np->n_name != NULL &&
  41                             *np->n_name != '\0') {
  42                                 strncpy(hostbuf, np->n_name, sizeof(hostbuf));
  43                                 hostbuf[sizeof(hostbuf) - 1] = '\0';
  44                                 return (hostbuf);
  45                         }
  46                 }
  47         }
  48
  49         if (family == AF_INET) {
  50                 return (inet_ntoa(ipa));
  51         }
  52 #ifdef  USE_INET6
  53         (void) inet_ntop(AF_INET6, ip, hostbuf, sizeof(hostbuf) - 1);
  54         hostbuf[MAXHOSTNAMELEN] = '\0';
  55         return (hostbuf);
  56 #else
  57         return ("IPv6");
  58 #endif
  59 }