Prevent modification of permanent ARP entries (PR kern/7649)

Ignore ARP replies from the wrong interface (discussion on mailing list)
Add interface name to a couple of error messages
This commit is contained in:
Bill Fenner 1998-09-17 00:04:21 +00:00
parent c5e6ca4410
commit dd9b6dde89
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=39389

View file

@ -31,7 +31,7 @@
* SUCH DAMAGE.
*
* @(#)if_ether.c 8.1 (Berkeley) 6/10/93
* $Id: if_ether.c,v 1.46 1998/06/07 17:12:12 dfr Exp $
* $Id: if_ether.c,v 1.47 1998/06/12 03:48:14 julian Exp $
*/
/*
@ -494,11 +494,28 @@ in_arpinput(m)
}
la = arplookup(isaddr.s_addr, itaddr.s_addr == myaddr.s_addr, 0);
if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
if (rt->rt_ifp != &ac->ac_if) {
log(LOG_ERR, "arp: %s is on %s%d but got reply from %6D on %s%d\n",
inet_ntoa(isaddr),
rt->rt_ifp->if_name, rt->rt_ifp->if_unit,
ea->arp_sha, ":",
ac->ac_if.if_name, ac->ac_if.if_unit);
goto reply;
}
if (sdl->sdl_alen &&
bcmp((caddr_t)ea->arp_sha, LLADDR(sdl), sdl->sdl_alen))
log(LOG_INFO, "arp: %s moved from %6D to %6D\n",
inet_ntoa(isaddr), (u_char *)LLADDR(sdl), ":",
ea->arp_sha, ":");
if (rt->rt_expire)
log(LOG_INFO, "arp: %s moved from %6D to %6D on %s%d\n",
inet_ntoa(isaddr), (u_char *)LLADDR(sdl), ":",
ea->arp_sha, ":",
ac->ac_if.if_name, ac->ac_if.if_unit);
else {
log(LOG_ERR,
"arp: %6D attempts to modify permanent entry for %s on %s%d",
ea->arp_sha, ":", inet_ntoa(isaddr),
ac->ac_if.if_name, ac->ac_if.if_unit);
goto reply;
}
(void)memcpy(LLADDR(sdl), ea->arp_sha, sizeof(ea->arp_sha));
sdl->sdl_alen = sizeof(ea->arp_sha);
if (rt->rt_expire)