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/*
* Copyright (c) 1995
* Bill Paul <wpaul@ctr.columbia.edu>. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Bill Paul.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* ethernet address conversion and lookup routines
*
* Written by Bill Paul <wpaul@ctr.columbia.edu>
* Center for Telecommunications Research
* Columbia University, New York City
*
* $Id$
*/
#include <stdio.h>
#include <paths.h>
#include <sys/types.h>
#include <string.h>
#include <stdlib.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <net/ethernet.h>
#ifdef YP
#include <rpc/rpc.h>
#include <rpcsvc/yp_prot.h>
#include <rpcsvc/ypclnt.h>
#endif
#ifndef _PATH_ETHERS
#define _PATH_ETHERS "/etc/ethers"
#endif
/*
* Parse a string of text containing an ethernet address and hostname
* and separate it into its component parts.
*/
int ether_line(l, e, hostname)
char *l;
struct ether_addr *e;
char *hostname;
{
int i, o[6];
i = sscanf(l, "%x:%x:%x:%x:%x:%x %s", &o[0], &o[1], &o[2],
&o[3], &o[4], &o[5],
hostname);
if (i != 7)
return (i);
for (i=0; i<6; i++)
e->octet[i] = o[i];
return (0);
}
/*
* Convert an ASCII representation of an ethernet address to
* binary form.
*/
struct ether_addr *ether_aton(a)
char *a;
{
int i;
static struct ether_addr o;
unsigned int o0, o1, o2, o3, o4, o5;
i = sscanf(a, "%x:%x:%x:%x:%x:%x", &o0, &o1, &o2, &o3, &o4, &o5);
if (i != 6)
return (NULL);
o.octet[0]=o0;
o.octet[1]=o1;
o.octet[2]=o2;
o.octet[3]=o3;
o.octet[4]=o4;
o.octet[5]=o5;
return ((struct ether_addr *)&o);
}
/*
* Convert a binary representation of an ethernet address to
* an ASCII string.
*/
char *ether_ntoa(n)
struct ether_addr *n;
{
int i;
static char a[18];
i = sprintf(a,"%x:%x:%x:%x:%x:%x",n->octet[0],n->octet[1],n->octet[2],
n->octet[3],n->octet[4],n->octet[5]);
if (i < 11)
return (NULL);
return ((char *)&a);
}
/*
* Map an ethernet address to a hostname. Use either /etc/ethers or
* NIS/YP.
*/
int ether_ntohost(hostname, e)
char *hostname;
struct ether_addr *e;
{
FILE *fp;
char buf[BUFSIZ + 2];
struct ether_addr local_ether;
char local_host[MAXHOSTNAMELEN];
#ifdef YP
char *result;
int resultlen;
char *ether_a;
char *yp_domain;
#endif
if ((fp = fopen(_PATH_ETHERS, "r")) == NULL)
return (1);
while (fgets(buf,BUFSIZ,fp)) {
if (buf[0] == '#')
continue;
#ifdef YP
if (buf[0] == '+') {
if (yp_get_default_domain(&yp_domain))
continue;
ether_a = ether_ntoa(e);
if (yp_match(yp_domain, "ethers.byaddr", ether_a,
strlen(ether_a), &result, &resultlen)) {
continue;
}
strncpy(buf, result, resultlen);
buf[resultlen] = '\0';
free(result);
}
#endif
if (!ether_line(buf, &local_ether, local_host)) {
if (!bcmp((char *)&local_ether.octet[0],
(char *)&e->octet[0], 6)) {
/* We have a match */
strcpy(hostname, local_host);
fclose(fp);
return(0);
}
}
}
fclose(fp);
return (1);
}
/*
* Map a hostname to an ethernet address using /etc/ethers or
* NIS/YP.
*/
int ether_hostton(hostname, e)
char *hostname;
struct ether_addr *e;
{
FILE *fp;
char buf[BUFSIZ + 2];
struct ether_addr local_ether;
char local_host[MAXHOSTNAMELEN];
#ifdef YP
char *result;
int resultlen;
char *yp_domain;
#endif
if ((fp = fopen(_PATH_ETHERS, "r")) == NULL)
return (1);
while (fgets(buf,BUFSIZ,fp)) {
if (buf[0] == '#')
continue;
#ifdef YP
if (buf[0] == '+') {
if (yp_get_default_domain(&yp_domain))
continue;
if (yp_match(yp_domain, "ethers.byname", hostname,
strlen(hostname), &result, &resultlen)) {
continue;
}
strncpy(buf, result, resultlen);
buf[resultlen] = '\0';
free(result);
}
#endif
if (!ether_line(buf, &local_ether, local_host)) {
if (!strcmp(hostname, local_host)) {
/* We have a match */
bcopy((char *)&local_ether.octet[0],
(char *)&e->octet[0], 6);
fclose(fp);
return(0);
}
}
}
fclose(fp);
return (1);
}
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