2 * Copyright (c) 1995 Bill Paul <wpaul@ctr.columbia.edu>.
3 * Copyright (c) 2007 Robert N. M. Watson
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. All advertising materials mentioning features or use of this software
15 * must display the following acknowledgement:
16 * This product includes software developed by Bill Paul.
17 * 4. Neither the name of the author nor the names of any co-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 Bill Paul 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 * ethernet address conversion and lookup routines
35 * Written by Bill Paul <wpaul@ctr.columbia.edu>
36 * Center for Telecommunications Research
37 * Columbia University, New York City
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
43 #include <sys/types.h>
44 #include <sys/param.h>
45 #include <sys/socket.h>
47 #include <net/ethernet.h>
51 #include <rpcsvc/yp_prot.h>
52 #include <rpcsvc/ypclnt.h>
61 #define _PATH_ETHERS "/etc/ethers"
65 * Parse a string of text containing an ethernet address and hostname and
66 * separate it into its component parts.
69 ether_line(const char *l, struct ether_addr *e, char *hostname)
73 i = sscanf(l, "%x:%x:%x:%x:%x:%x %s", &o[0], &o[1], &o[2], &o[3],
74 &o[4], &o[5], hostname);
76 for (i = 0; i < 6; i++)
85 * Convert an ASCII representation of an ethernet address to binary form.
88 ether_aton_r(const char *a, struct ether_addr *e)
91 unsigned int o0, o1, o2, o3, o4, o5;
93 i = sscanf(a, "%x:%x:%x:%x:%x:%x", &o0, &o1, &o2, &o3, &o4, &o5);
106 ether_aton(const char *a)
108 static struct ether_addr e;
110 return (ether_aton_r(a, &e));
114 * Convert a binary representation of an ethernet address to an ASCII string.
117 ether_ntoa_r(const struct ether_addr *n, char *a)
121 i = sprintf(a, "%02x:%02x:%02x:%02x:%02x:%02x", n->octet[0],
122 n->octet[1], n->octet[2], n->octet[3], n->octet[4], n->octet[5]);
129 ether_ntoa(const struct ether_addr *n)
133 return (ether_ntoa_r(n, a));
137 * Map an ethernet address to a hostname. Use either /etc/ethers or NIS/YP.
140 ether_ntohost(char *hostname, const struct ether_addr *e)
143 char buf[BUFSIZ + 2];
144 struct ether_addr local_ether;
145 char local_host[MAXHOSTNAMELEN];
153 if ((fp = fopen(_PATH_ETHERS, "re")) == NULL)
155 while (fgets(buf,BUFSIZ,fp)) {
160 if (yp_get_default_domain(&yp_domain))
162 ether_a = ether_ntoa(e);
163 if (yp_match(yp_domain, "ethers.byaddr", ether_a,
164 strlen(ether_a), &result, &resultlen)) {
167 strncpy(buf, result, resultlen);
168 buf[resultlen] = '\0';
172 if (!ether_line(buf, &local_ether, local_host)) {
173 if (!bcmp((char *)&local_ether.octet[0],
174 (char *)&e->octet[0], 6)) {
175 /* We have a match. */
176 strcpy(hostname, local_host);
187 * Map a hostname to an ethernet address using /etc/ethers or NIS/YP.
190 ether_hostton(const char *hostname, struct ether_addr *e)
193 char buf[BUFSIZ + 2];
194 struct ether_addr local_ether;
195 char local_host[MAXHOSTNAMELEN];
202 if ((fp = fopen(_PATH_ETHERS, "re")) == NULL)
204 while (fgets(buf,BUFSIZ,fp)) {
209 if (yp_get_default_domain(&yp_domain))
211 if (yp_match(yp_domain, "ethers.byname", hostname,
212 strlen(hostname), &result, &resultlen)) {
215 strncpy(buf, result, resultlen);
216 buf[resultlen] = '\0';
220 if (!ether_line(buf, &local_ether, local_host)) {
221 if (!strcmp(hostname, local_host)) {
222 /* We have a match. */
223 bcopy((char *)&local_ether.octet[0],
224 (char *)&e->octet[0], 6);