2 * Copyright (c) 1988, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * @(#) Copyright (c) 1988, 1993 The Regents of the University of California. All rights reserved.
34 * @(#)hostname.c 8.1 (Berkeley) 5/31/93
35 * $FreeBSD: src/bin/hostname/hostname.c,v 1.10.2.1 2001/08/01 02:40:23 obrien Exp $
36 * $DragonFly: src/bin/hostname/hostname.c,v 1.14 2008/09/02 22:20:55 swildner Exp $
39 #include <sys/param.h>
40 #include <sys/ioctl.h>
41 #include <sys/socket.h>
42 #include <sys/sysctl.h>
43 #include <sys/module.h>
44 #include <sys/linker.h>
46 #include <net/ethernet.h>
48 #include <net/if_var.h>
49 #include <net/if_dl.h>
50 #include <net/if_types.h>
51 #include <net/route.h>
52 #include <netinet/in.h>
61 #include <sys/types.h>
62 #include <netinet/in.h>
63 #include <arpa/inet.h>
67 #define HST_IF (1 << 0)
68 #define HST_IF_V6 (1 << 1)
69 #define HST_IF_V4 (1 << 2)
74 * Expand the compacted form of addresses as returned via the
75 * configuration read via sysctl().
76 * Lifted from getifaddrs(3)
79 static void rt_xaddrs(caddr_t, caddr_t, struct rt_addrinfo *);
80 static void usage (void);
83 ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
84 #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))
88 rt_xaddrs(caddr_t cp, caddr_t cplim, struct rt_addrinfo *rtinfo)
93 memset(rtinfo->rti_info, 0, sizeof(rtinfo->rti_info));
94 for (i = 0; (i < RTAX_MAX) && (cp < cplim); i++) {
95 if ((rtinfo->rti_addrs & (1 << i)) == 0)
97 rtinfo->rti_info[i] = sa = (struct sockaddr *)cp;
103 main(int argc, char **argv)
105 int ch, sflag, rflag, ret, flag6, iflag;
107 char hostname[MAXHOSTNAMELEN];
108 char *srflag, *siflag;
115 char *buf, *next, *p;
117 struct sockaddr_dl *sdl;
118 struct rt_msghdr *rtm;
119 struct if_msghdr *ifm;
120 struct ifa_msghdr *ifam;
121 struct rt_addrinfo info;
122 struct sockaddr_in *sai;
123 struct sockaddr_in6 *sai6;
127 iflag = sflag = rflag = 0;
131 while ((ch = getopt(argc, argv, "46i:r:s")) != -1) {
141 silen = strlen(siflag);
167 if (rflag && (iflag & HST_IF))
170 if ((iflag & HST_IF_V6) && (iflag & HST_IF_V4))
173 if (!(iflag & HST_IF) && ((iflag & HST_IF_V6)||iflag & HST_IF_V4))
176 if (iflag & HST_IF) {
181 mib[4] = NET_RT_IFLIST;
187 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
188 err(1, "sysctl: iflist-sysctl-estimate");
189 if ((buf = malloc(needed)) == NULL)
190 err(1, "malloc failed");
191 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
192 err(1, "sysctl: retrieval of interface table");
194 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
195 rtm = (struct rt_msghdr *)(void *)next;
196 if (rtm->rtm_version != RTM_VERSION)
198 switch (rtm->rtm_type) {
200 ifm = (struct if_msghdr *)(void *)rtm;
202 if ((ifm->ifm_addrs & RTA_IFP) == 0)
204 sdl = (struct sockaddr_dl *)(ifm + 1);
205 if (silen != sdl->sdl_nlen)
207 if (!strncmp(siflag, sdl->sdl_data, silen)) {
208 idx = ifm->ifm_index;
212 ifam = (struct ifa_msghdr *)(void *)rtm;
214 if (ifam->ifam_index == idx) {
215 info.rti_addrs = ifam->ifam_addrs;
216 rt_xaddrs((char *)(ifam + 1),
217 ifam->ifam_msglen + (char *)ifam, &info);
218 sai = (struct sockaddr_in *)info.rti_info[RTAX_IFA];
220 if (iflag & HST_IF_V6) {
221 if (sai->sin_family == AF_INET6) {
222 sai6 = (struct sockaddr_in6 *)info.rti_info[RTAX_IFA];
223 hst = gethostbyaddr(&sai6->sin6_addr,
224 sizeof(sai6->sin6_addr),AF_INET6);
226 if (h_errno == NETDB_SUCCESS) {
232 if ((sai->sin_family == AF_INET)) {
234 hst = gethostbyaddr(&sai->sin_addr,
235 sizeof(sai->sin_addr),AF_INET);
237 if (h_errno == NETDB_SUCCESS) {
251 errx(1,"interface not found");
253 errx(1, "ip not found on interface");
255 if (h_errno == NETDB_SUCCESS) {
256 if (sethostname(hst->h_name, (int)strlen(hst->h_name)))
257 err(1, "sethostname");
258 } else if (h_errno == HOST_NOT_FOUND) {
259 errx(1,"hostname not found");
261 herror("gethostbyaddr");
265 ret = inet_pton(AF_INET, srflag, &ia);
268 ret = inet_pton(AF_INET6, srflag, &ia6);
271 errx(1, "invalid ip address");
278 hst = gethostbyaddr(&ia6, sizeof(ia6), AF_INET6);
280 hst = gethostbyaddr(&ia, sizeof(ia), AF_INET);
282 if (h_errno == HOST_NOT_FOUND)
283 errx(1,"host not found\n");
286 if (sethostname(hst->h_name, (int)strlen(hst->h_name)))
287 err(1, "sethostname");
289 if (sethostname(*argv, (int)strlen(*argv)))
290 err(1, "sethostname");
292 if (gethostname(hostname, (int)sizeof(hostname)))
293 err(1, "gethostname");
294 if (sflag && (p = strchr(hostname, '.')))
296 printf("%s\n", hostname);
304 fprintf(stderr, "usage: hostname [-s] [name-of-host |"
305 " -r ip-address | -i interface [-4 | -6]]\n");