xref: /freebsd/sbin/ipf/libipf/hostname.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 
2 /*
3  * Copyright (C) 2012 by Darren Reed.
4  *
5  * See the IPFILTER.LICENCE file for details on licencing.
6  *
7  * $Id$
8  */
9 
10 #include "ipf.h"
11 
12 char *
13 hostname(int family, void *ip)
14 {
15 	static char hostbuf[MAXHOSTNAMELEN+1];
16 	struct hostent *hp;
17 	struct in_addr ipa;
18 	struct netent *np;
19 
20 	memset(&ipa, 0, sizeof(ipa));	/* XXX gcc */
21 
22 	if (family == AF_INET) {
23 		ipa.s_addr = *(u_32_t *)ip;
24 		if (ipa.s_addr == htonl(0xfedcba98))
25 			return ("test.host.dots");
26 	}
27 
28 	if ((opts & OPT_NORESOLVE) == 0) {
29 		if (family == AF_INET) {
30 			hp = gethostbyaddr(ip, 4, AF_INET);
31 			if (hp != NULL && hp->h_name != NULL &&
32 			    *hp->h_name != '\0') {
33 				strncpy(hostbuf, hp->h_name, sizeof(hostbuf));
34 				hostbuf[sizeof(hostbuf) - 1] = '\0';
35 				return (hostbuf);
36 			}
37 
38 			np = getnetbyaddr(ipa.s_addr, AF_INET);
39 			if (np != NULL && np->n_name != NULL &&
40 			    *np->n_name != '\0') {
41 				strncpy(hostbuf, np->n_name, sizeof(hostbuf));
42 				hostbuf[sizeof(hostbuf) - 1] = '\0';
43 				return (hostbuf);
44 			}
45 		}
46 	}
47 
48 	if (family == AF_INET) {
49 		return (inet_ntoa(ipa));
50 	}
51 #ifdef  USE_INET6
52 	(void) inet_ntop(AF_INET6, ip, hostbuf, sizeof(hostbuf) - 1);
53 	hostbuf[MAXHOSTNAMELEN] = '\0';
54 	return (hostbuf);
55 #else
56 	return ("IPv6");
57 #endif
58 }
59