220 lines
6.1 KiB
C
220 lines
6.1 KiB
C
/*
|
|
* Copyright (c) 1984, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* Sun Microsystems, Inc.
|
|
*
|
|
* 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 the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char copyright[] =
|
|
"@(#) Copyright (c) 1984, 1993\n\
|
|
The Regents of the University of California. All rights reserved.\n";
|
|
#endif /* not lint */
|
|
|
|
#ifndef lint
|
|
static char sccsid[] = "@(#)arp.c 8.2 (Berkeley) 1/2/94";
|
|
#endif /* not lint */
|
|
|
|
/*
|
|
* set arp table entries
|
|
*/
|
|
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/file.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/sysctl.h>
|
|
|
|
#include <net/if.h>
|
|
#include <net/if_dl.h>
|
|
#include <net/if_types.h>
|
|
#include <net/route.h>
|
|
|
|
#include <netinet/in.h>
|
|
#include <netinet/if_ether.h>
|
|
|
|
#include <arpa/inet.h>
|
|
|
|
#include <netdb.h>
|
|
#include <errno.h>
|
|
#include <nlist.h>
|
|
#include <stdio.h>
|
|
#include <paths.h>
|
|
#include <syslog.h>
|
|
|
|
extern int errno;
|
|
static int pid;
|
|
static int s = -1;
|
|
|
|
getsocket() {
|
|
if (s < 0) {
|
|
s = socket(PF_ROUTE, SOCK_RAW, 0);
|
|
if (s < 0) {
|
|
perror("arp: socket");
|
|
exit(1);
|
|
}
|
|
}
|
|
}
|
|
|
|
struct sockaddr_in so_mask = {8, 0, 0, { 0xffffffff}};
|
|
struct sockaddr_inarp blank_sin = {sizeof(blank_sin), AF_INET }, sin_m;
|
|
struct sockaddr_dl blank_sdl = {sizeof(blank_sdl), AF_LINK }, sdl_m;
|
|
int expire_time, flags, export_only, doing_proxy;
|
|
struct {
|
|
struct rt_msghdr m_rtm;
|
|
char m_space[512];
|
|
} m_rtmsg;
|
|
|
|
/*
|
|
* Set an individual arp entry
|
|
*/
|
|
arptab_set(eaddr, host)
|
|
u_char *eaddr;
|
|
u_long host;
|
|
{
|
|
register struct sockaddr_inarp *sin = &sin_m;
|
|
register struct sockaddr_dl *sdl;
|
|
register struct rt_msghdr *rtm = &(m_rtmsg.m_rtm);
|
|
struct timeval time;
|
|
|
|
getsocket();
|
|
pid = getpid();
|
|
sdl_m = blank_sdl;
|
|
sin_m = blank_sin;
|
|
sin->sin_addr.s_addr = host;
|
|
bcopy((char *)eaddr, (u_char *)LLADDR(&sdl_m), 6);
|
|
sdl_m.sdl_alen = 6;
|
|
doing_proxy = flags = export_only = expire_time = 0;
|
|
gettimeofday(&time, 0);
|
|
expire_time = time.tv_sec + 20 * 60;
|
|
|
|
tryagain:
|
|
if (rtmsg(RTM_GET) < 0) {
|
|
syslog(LOG_ERR,"%s: %m", inet_ntoa(sin->sin_addr));
|
|
return (1);
|
|
}
|
|
sin = (struct sockaddr_inarp *)(rtm + 1);
|
|
sdl = (struct sockaddr_dl *)(sin->sin_len + (char *)sin);
|
|
if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) {
|
|
if (sdl->sdl_family == AF_LINK &&
|
|
(rtm->rtm_flags & RTF_LLINFO) &&
|
|
!(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) {
|
|
case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023:
|
|
case IFT_ISO88024: case IFT_ISO88025:
|
|
goto overwrite;
|
|
}
|
|
if (doing_proxy == 0) {
|
|
syslog(LOG_ERR, "arptab_set: can only proxy for %s\n", inet_ntoa(sin->sin_addr));
|
|
return (1);
|
|
}
|
|
if (sin_m.sin_other & SIN_PROXY) {
|
|
syslog(LOG_ERR,"arptab_set: proxy entry exists for non 802 device\n");
|
|
return(1);
|
|
}
|
|
sin_m.sin_other = SIN_PROXY;
|
|
export_only = 1;
|
|
goto tryagain;
|
|
}
|
|
overwrite:
|
|
if (sdl->sdl_family != AF_LINK) {
|
|
syslog(LOG_ERR,"arptab_set: cannot intuit interface index and type for %s\n", inet_ntoa(sin->sin_addr));
|
|
return (1);
|
|
}
|
|
sdl_m.sdl_type = sdl->sdl_type;
|
|
sdl_m.sdl_index = sdl->sdl_index;
|
|
return (rtmsg(RTM_ADD));
|
|
}
|
|
|
|
rtmsg(cmd)
|
|
{
|
|
static int seq;
|
|
int rlen;
|
|
register struct rt_msghdr *rtm = &m_rtmsg.m_rtm;
|
|
register char *cp = m_rtmsg.m_space;
|
|
register int l;
|
|
|
|
errno = 0;
|
|
if (cmd == RTM_DELETE)
|
|
goto doit;
|
|
bzero((char *)&m_rtmsg, sizeof(m_rtmsg));
|
|
rtm->rtm_flags = flags;
|
|
rtm->rtm_version = RTM_VERSION;
|
|
|
|
switch (cmd) {
|
|
default:
|
|
syslog(LOG_ERR, "arptap_set: internal wrong cmd\n");
|
|
exit(1);
|
|
case RTM_ADD:
|
|
rtm->rtm_addrs |= RTA_GATEWAY;
|
|
rtm->rtm_rmx.rmx_expire = expire_time;
|
|
rtm->rtm_inits = RTV_EXPIRE;
|
|
rtm->rtm_flags |= (RTF_HOST | RTF_STATIC);
|
|
sin_m.sin_other = 0;
|
|
if (doing_proxy) {
|
|
if (export_only)
|
|
sin_m.sin_other = SIN_PROXY;
|
|
else {
|
|
rtm->rtm_addrs |= RTA_NETMASK;
|
|
rtm->rtm_flags &= ~RTF_HOST;
|
|
}
|
|
}
|
|
/* FALLTHROUGH */
|
|
case RTM_GET:
|
|
rtm->rtm_addrs |= RTA_DST;
|
|
}
|
|
#define NEXTADDR(w, s) \
|
|
if (rtm->rtm_addrs & (w)) { \
|
|
bcopy((char *)&s, cp, sizeof(s)); cp += sizeof(s);}
|
|
|
|
NEXTADDR(RTA_DST, sin_m);
|
|
NEXTADDR(RTA_GATEWAY, sdl_m);
|
|
NEXTADDR(RTA_NETMASK, so_mask);
|
|
|
|
rtm->rtm_msglen = cp - (char *)&m_rtmsg;
|
|
doit:
|
|
l = rtm->rtm_msglen;
|
|
rtm->rtm_seq = ++seq;
|
|
rtm->rtm_type = cmd;
|
|
if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) {
|
|
if (errno != ESRCH && errno != EEXIST) {
|
|
syslog(LOG_ERR, "writing to routing socket: %m");
|
|
return (-1);
|
|
}
|
|
}
|
|
do {
|
|
l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg));
|
|
} while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid));
|
|
if (l < 0)
|
|
syslog(LOG_ERR, "arptab_set: read from routing socket: %m");
|
|
return (0);
|
|
}
|