646 lines
18 KiB
C
646 lines
18 KiB
C
/*
|
|
* Copyright (c) 1982, 1986, 1988, 1993
|
|
* The Regents of the University of California. 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 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.
|
|
*
|
|
* @(#)if_ether.c 8.1 (Berkeley) 6/10/93
|
|
* $Id: if_ether.c,v 1.9 1994/12/22 21:56:21 wollman Exp $
|
|
*/
|
|
|
|
/*
|
|
* Ethernet address resolution protocol.
|
|
* TODO:
|
|
* add "inuse/lock" bit (or ref. count) along with valid bit
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/mbuf.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/time.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/errno.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/syslog.h>
|
|
|
|
#include <net/if.h>
|
|
#include <net/if_dl.h>
|
|
#include <net/route.h>
|
|
|
|
#include <netinet/in.h>
|
|
#include <netinet/in_systm.h>
|
|
#include <netinet/in_var.h>
|
|
#include <netinet/ip.h>
|
|
#include <netinet/if_ether.h>
|
|
|
|
#define SIN(s) ((struct sockaddr_in *)s)
|
|
#define SDL(s) ((struct sockaddr_dl *)s)
|
|
#define SRP(s) ((struct sockaddr_inarp *)s)
|
|
|
|
/*
|
|
* ARP trailer negotiation. Trailer protocol is not IP specific,
|
|
* but ARP request/response use IP addresses.
|
|
*/
|
|
#define ETHERTYPE_IPTRAILERS ETHERTYPE_TRAIL
|
|
|
|
|
|
/* timer values */
|
|
int arpt_prune = (5*60*1); /* walk list every 5 minutes */
|
|
int arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
|
|
int arpt_down = 20; /* once declared down, don't send for 20 secs */
|
|
#define rt_expire rt_rmx.rmx_expire
|
|
|
|
static void arprequest __P((struct arpcom *, u_long *, u_long *, u_char *));
|
|
static void arptfree __P((struct llinfo_arp *));
|
|
static void arptimer __P((void *));
|
|
static struct llinfo_arp *arplookup __P((u_long, int, int));
|
|
static void in_arpinput __P((struct mbuf *));
|
|
|
|
extern struct ifnet loif;
|
|
struct llinfo_arp llinfo_arp = {&llinfo_arp, &llinfo_arp};
|
|
struct ifqueue arpintrq = {0, 0, 0, 50};
|
|
int arp_inuse, arp_allocated, arp_intimer;
|
|
int arp_maxtries = 5;
|
|
int useloopback = 1; /* use loopback interface for local traffic */
|
|
int arpinit_done = 0;
|
|
|
|
#ifdef ARP_PROXYALL
|
|
int arp_proxyall = 1;
|
|
#endif
|
|
|
|
/*
|
|
* Support: format an IP address. There should be a standard kernel routine
|
|
* to do this.
|
|
*/
|
|
static char *
|
|
arp_ntoa(struct in_addr *x)
|
|
{
|
|
static char buf[4*sizeof "123"];
|
|
unsigned char *ucp = (unsigned char *)x;
|
|
|
|
sprintf(buf, "%d.%d.%d.%d",
|
|
ucp[0] & 0xff,
|
|
ucp[1] & 0xff,
|
|
ucp[2] & 0xff,
|
|
ucp[3] & 0xff);
|
|
return buf;
|
|
}
|
|
|
|
/*
|
|
* Timeout routine. Age arp_tab entries periodically.
|
|
*/
|
|
/* ARGSUSED */
|
|
static void
|
|
arptimer(ignored_arg)
|
|
void *ignored_arg;
|
|
{
|
|
int s = splnet();
|
|
register struct llinfo_arp *la = llinfo_arp.la_next;
|
|
|
|
timeout(arptimer, (caddr_t)0, arpt_prune * hz);
|
|
while (la != &llinfo_arp) {
|
|
register struct rtentry *rt = la->la_rt;
|
|
la = la->la_next;
|
|
if (rt->rt_expire && rt->rt_expire <= time.tv_sec)
|
|
arptfree(la->la_prev); /* timer has expired, clear */
|
|
}
|
|
splx(s);
|
|
}
|
|
|
|
/*
|
|
* Parallel to llc_rtrequest.
|
|
*/
|
|
static void
|
|
arp_rtrequest(req, rt, sa)
|
|
int req;
|
|
register struct rtentry *rt;
|
|
struct sockaddr *sa;
|
|
{
|
|
register struct sockaddr *gate = rt->rt_gateway;
|
|
register struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
|
|
static struct sockaddr_dl null_sdl = {sizeof(null_sdl), AF_LINK};
|
|
|
|
if (!arpinit_done) {
|
|
arpinit_done = 1;
|
|
timeout(arptimer, (caddr_t)0, hz);
|
|
}
|
|
if (rt->rt_flags & RTF_GATEWAY)
|
|
return;
|
|
switch (req) {
|
|
|
|
case RTM_ADD:
|
|
/*
|
|
* XXX: If this is a manually added route to interface
|
|
* such as older version of routed or gated might provide,
|
|
* restore cloning bit.
|
|
*/
|
|
if ((rt->rt_flags & RTF_HOST) == 0 &&
|
|
SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
|
|
rt->rt_flags |= RTF_CLONING;
|
|
#if 0
|
|
/*
|
|
* Actually, all IP gateway routes should have the cloning
|
|
* flag turned on. We can't do this yet because the expiration
|
|
* stuff isn't working yet.
|
|
*/
|
|
if (rt->rt_flags & RTF_GATEWAY) {
|
|
rt->rt_flags |= RTF_CLONING;
|
|
}
|
|
#endif
|
|
if (rt->rt_flags & RTF_CLONING) {
|
|
/*
|
|
* Case 1: This route should come from a route to iface.
|
|
*/
|
|
rt_setgate(rt, rt_key(rt),
|
|
(struct sockaddr *)&null_sdl);
|
|
gate = rt->rt_gateway;
|
|
SDL(gate)->sdl_type = rt->rt_ifp->if_type;
|
|
SDL(gate)->sdl_index = rt->rt_ifp->if_index;
|
|
rt->rt_expire = time.tv_sec;
|
|
break;
|
|
}
|
|
/* Announce a new entry if requested. */
|
|
if (rt->rt_flags & RTF_ANNOUNCE)
|
|
arprequest((struct arpcom *)rt->rt_ifp,
|
|
&SIN(rt_key(rt))->sin_addr.s_addr,
|
|
&SIN(rt_key(rt))->sin_addr.s_addr,
|
|
(u_char *)LLADDR(SDL(gate)));
|
|
/*FALLTHROUGH*/
|
|
case RTM_RESOLVE:
|
|
if (gate->sa_family != AF_LINK ||
|
|
gate->sa_len < sizeof(null_sdl)) {
|
|
log(LOG_DEBUG, "arp_rtrequest: bad gateway value");
|
|
break;
|
|
}
|
|
SDL(gate)->sdl_type = rt->rt_ifp->if_type;
|
|
SDL(gate)->sdl_index = rt->rt_ifp->if_index;
|
|
if (la != 0)
|
|
break; /* This happens on a route change */
|
|
/*
|
|
* Case 2: This route may come from cloning, or a manual route
|
|
* add with a LL address.
|
|
*/
|
|
R_Malloc(la, struct llinfo_arp *, sizeof(*la));
|
|
rt->rt_llinfo = (caddr_t)la;
|
|
if (la == 0) {
|
|
log(LOG_DEBUG, "arp_rtrequest: malloc failed\n");
|
|
break;
|
|
}
|
|
arp_inuse++, arp_allocated++;
|
|
Bzero(la, sizeof(*la));
|
|
la->la_rt = rt;
|
|
rt->rt_flags |= RTF_LLINFO;
|
|
insque(la, &llinfo_arp);
|
|
if (SIN(rt_key(rt))->sin_addr.s_addr ==
|
|
(IA_SIN(rt->rt_ifa))->sin_addr.s_addr) {
|
|
/*
|
|
* This test used to be
|
|
* if (loif.if_flags & IFF_UP)
|
|
* It allowed local traffic to be forced
|
|
* through the hardware by configuring the loopback down.
|
|
* However, it causes problems during network configuration
|
|
* for boards that can't receive packets they send.
|
|
* It is now necessary to clear "useloopback" and remove
|
|
* the route to force traffic out to the hardware.
|
|
*/
|
|
rt->rt_expire = 0;
|
|
Bcopy(((struct arpcom *)rt->rt_ifp)->ac_enaddr,
|
|
LLADDR(SDL(gate)), SDL(gate)->sdl_alen = 6);
|
|
if (useloopback)
|
|
rt->rt_ifp = &loif;
|
|
|
|
}
|
|
break;
|
|
|
|
case RTM_DELETE:
|
|
if (la == 0)
|
|
break;
|
|
arp_inuse--;
|
|
remque(la);
|
|
rt->rt_llinfo = 0;
|
|
rt->rt_flags &= ~RTF_LLINFO;
|
|
if (la->la_hold)
|
|
m_freem(la->la_hold);
|
|
Free((caddr_t)la);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Broadcast an ARP packet, asking who has addr on interface ac.
|
|
*/
|
|
void
|
|
arpwhohas(ac, addr)
|
|
register struct arpcom *ac;
|
|
register struct in_addr *addr;
|
|
{
|
|
arprequest(ac, &ac->ac_ipaddr.s_addr, &addr->s_addr, ac->ac_enaddr);
|
|
}
|
|
|
|
/*
|
|
* Broadcast an ARP request. Caller specifies:
|
|
* - arp header source ip address
|
|
* - arp header target ip address
|
|
* - arp header source ethernet address
|
|
*/
|
|
static void
|
|
arprequest(ac, sip, tip, enaddr)
|
|
register struct arpcom *ac;
|
|
register u_long *sip, *tip;
|
|
register u_char *enaddr;
|
|
{
|
|
register struct mbuf *m;
|
|
register struct ether_header *eh;
|
|
register struct ether_arp *ea;
|
|
struct sockaddr sa;
|
|
|
|
if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
|
|
return;
|
|
m->m_len = sizeof(*ea);
|
|
m->m_pkthdr.len = sizeof(*ea);
|
|
MH_ALIGN(m, sizeof(*ea));
|
|
ea = mtod(m, struct ether_arp *);
|
|
eh = (struct ether_header *)sa.sa_data;
|
|
bzero((caddr_t)ea, sizeof (*ea));
|
|
bcopy((caddr_t)etherbroadcastaddr, (caddr_t)eh->ether_dhost,
|
|
sizeof(eh->ether_dhost));
|
|
eh->ether_type = ETHERTYPE_ARP; /* if_output will swap */
|
|
ea->arp_hrd = htons(ARPHRD_ETHER);
|
|
ea->arp_pro = htons(ETHERTYPE_IP);
|
|
ea->arp_hln = sizeof(ea->arp_sha); /* hardware address length */
|
|
ea->arp_pln = sizeof(ea->arp_spa); /* protocol address length */
|
|
ea->arp_op = htons(ARPOP_REQUEST);
|
|
bcopy((caddr_t)enaddr, (caddr_t)ea->arp_sha, sizeof(ea->arp_sha));
|
|
bcopy((caddr_t)sip, (caddr_t)ea->arp_spa, sizeof(ea->arp_spa));
|
|
bcopy((caddr_t)tip, (caddr_t)ea->arp_tpa, sizeof(ea->arp_tpa));
|
|
sa.sa_family = AF_UNSPEC;
|
|
sa.sa_len = sizeof(sa);
|
|
(*ac->ac_if.if_output)(&ac->ac_if, m, &sa, (struct rtentry *)0);
|
|
}
|
|
|
|
/*
|
|
* Resolve an IP address into an ethernet address. If success,
|
|
* desten is filled in. If there is no entry in arptab,
|
|
* set one up and broadcast a request for the IP address.
|
|
* Hold onto this mbuf and resend it once the address
|
|
* is finally resolved. A return value of 1 indicates
|
|
* that desten has been filled in and the packet should be sent
|
|
* normally; a 0 return indicates that the packet has been
|
|
* taken over here, either now or for later transmission.
|
|
*/
|
|
int
|
|
arpresolve(ac, rt, m, dst, desten, rt0)
|
|
register struct arpcom *ac;
|
|
register struct rtentry *rt;
|
|
struct mbuf *m;
|
|
register struct sockaddr *dst;
|
|
register u_char *desten;
|
|
struct rtentry *rt0;
|
|
{
|
|
register struct llinfo_arp *la;
|
|
struct sockaddr_dl *sdl;
|
|
|
|
if (m->m_flags & M_BCAST) { /* broadcast */
|
|
bcopy((caddr_t)etherbroadcastaddr, (caddr_t)desten,
|
|
sizeof(etherbroadcastaddr));
|
|
return (1);
|
|
}
|
|
if (m->m_flags & M_MCAST) { /* multicast */
|
|
ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten);
|
|
return(1);
|
|
}
|
|
if (rt)
|
|
la = (struct llinfo_arp *)rt->rt_llinfo;
|
|
else {
|
|
la = arplookup(SIN(dst)->sin_addr.s_addr, 1, 0);
|
|
if (la)
|
|
rt = la->la_rt;
|
|
}
|
|
if (la == 0 || rt == 0) {
|
|
log(LOG_DEBUG, "arpresolve: can't allocate llinfo");
|
|
m_freem(m);
|
|
return (0);
|
|
}
|
|
sdl = SDL(rt->rt_gateway);
|
|
/*
|
|
* Check the address family and length is valid, the address
|
|
* is resolved; otherwise, try to resolve.
|
|
*/
|
|
if ((rt->rt_expire == 0 || rt->rt_expire > time.tv_sec) &&
|
|
sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
|
|
bcopy(LLADDR(sdl), desten, sdl->sdl_alen);
|
|
return 1;
|
|
}
|
|
/*
|
|
* There is an arptab entry, but no ethernet address
|
|
* response yet. Replace the held mbuf with this
|
|
* latest one.
|
|
*/
|
|
if (la->la_hold)
|
|
m_freem(la->la_hold);
|
|
la->la_hold = m;
|
|
if (rt->rt_expire) {
|
|
rt->rt_flags &= ~RTF_REJECT;
|
|
if (la->la_asked == 0 || rt->rt_expire != time.tv_sec) {
|
|
rt->rt_expire = time.tv_sec;
|
|
if (la->la_asked++ < arp_maxtries)
|
|
arpwhohas(ac, &(SIN(dst)->sin_addr));
|
|
else {
|
|
rt->rt_flags |= RTF_REJECT;
|
|
rt->rt_expire += arpt_down;
|
|
la->la_asked = 0;
|
|
}
|
|
|
|
}
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Common length and type checks are done here,
|
|
* then the protocol-specific routine is called.
|
|
*/
|
|
void
|
|
arpintr()
|
|
{
|
|
register struct mbuf *m;
|
|
register struct arphdr *ar;
|
|
int s;
|
|
|
|
while (arpintrq.ifq_head) {
|
|
s = splimp();
|
|
IF_DEQUEUE(&arpintrq, m);
|
|
splx(s);
|
|
if (m == 0 || (m->m_flags & M_PKTHDR) == 0)
|
|
panic("arpintr");
|
|
if (m->m_len >= sizeof(struct arphdr) &&
|
|
(ar = mtod(m, struct arphdr *)) &&
|
|
ntohs(ar->ar_hrd) == ARPHRD_ETHER &&
|
|
m->m_len >=
|
|
sizeof(struct arphdr) + 2 * ar->ar_hln + 2 * ar->ar_pln)
|
|
|
|
switch (ntohs(ar->ar_pro)) {
|
|
|
|
case ETHERTYPE_IP:
|
|
case ETHERTYPE_IPTRAILERS:
|
|
in_arpinput(m);
|
|
continue;
|
|
}
|
|
m_freem(m);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ARP for Internet protocols on 10 Mb/s Ethernet.
|
|
* Algorithm is that given in RFC 826.
|
|
* In addition, a sanity check is performed on the sender
|
|
* protocol address, to catch impersonators.
|
|
* We no longer handle negotiations for use of trailer protocol:
|
|
* Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent
|
|
* along with IP replies if we wanted trailers sent to us,
|
|
* and also sent them in response to IP replies.
|
|
* This allowed either end to announce the desire to receive
|
|
* trailer packets.
|
|
* We no longer reply to requests for ETHERTYPE_TRAIL protocol either,
|
|
* but formerly didn't normally send requests.
|
|
*/
|
|
static void
|
|
in_arpinput(m)
|
|
struct mbuf *m;
|
|
{
|
|
register struct ether_arp *ea;
|
|
register struct arpcom *ac = (struct arpcom *)m->m_pkthdr.rcvif;
|
|
struct ether_header *eh;
|
|
register struct llinfo_arp *la = 0;
|
|
register struct rtentry *rt;
|
|
struct in_ifaddr *ia, *maybe_ia = 0;
|
|
struct sockaddr_dl *sdl;
|
|
struct sockaddr sa;
|
|
struct in_addr isaddr, itaddr, myaddr;
|
|
int op;
|
|
|
|
ea = mtod(m, struct ether_arp *);
|
|
op = ntohs(ea->arp_op);
|
|
bcopy((caddr_t)ea->arp_spa, (caddr_t)&isaddr, sizeof (isaddr));
|
|
bcopy((caddr_t)ea->arp_tpa, (caddr_t)&itaddr, sizeof (itaddr));
|
|
for (ia = in_ifaddr; ia; ia = ia->ia_next)
|
|
if (ia->ia_ifp == &ac->ac_if) {
|
|
maybe_ia = ia;
|
|
if ((itaddr.s_addr == ia->ia_addr.sin_addr.s_addr) ||
|
|
(isaddr.s_addr == ia->ia_addr.sin_addr.s_addr))
|
|
break;
|
|
}
|
|
if (maybe_ia == 0)
|
|
goto out;
|
|
myaddr = ia ? ia->ia_addr.sin_addr : maybe_ia->ia_addr.sin_addr;
|
|
if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)ac->ac_enaddr,
|
|
sizeof (ea->arp_sha)))
|
|
goto out; /* it's from me, ignore it. */
|
|
if (!bcmp((caddr_t)ea->arp_sha, (caddr_t)etherbroadcastaddr,
|
|
sizeof (ea->arp_sha))) {
|
|
log(LOG_ERR,
|
|
"arp: ether address is broadcast for IP address %s!\n",
|
|
arp_ntoa(&isaddr));
|
|
goto out;
|
|
}
|
|
if (isaddr.s_addr == myaddr.s_addr) {
|
|
log(LOG_ERR,
|
|
"duplicate IP address %s! sent from ethernet address: %s\n",
|
|
arp_ntoa(&isaddr), ether_sprintf(ea->arp_sha));
|
|
itaddr = myaddr;
|
|
goto reply;
|
|
}
|
|
la = arplookup(isaddr.s_addr, itaddr.s_addr == myaddr.s_addr, 0);
|
|
if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
|
|
if (sdl->sdl_alen &&
|
|
bcmp((caddr_t)ea->arp_sha, LLADDR(sdl), sdl->sdl_alen))
|
|
log(LOG_INFO, "arp info overwritten for %s by %s\n",
|
|
arp_ntoa(&isaddr), ether_sprintf(ea->arp_sha));
|
|
bcopy((caddr_t)ea->arp_sha, LLADDR(sdl),
|
|
sdl->sdl_alen = sizeof(ea->arp_sha));
|
|
if (rt->rt_expire)
|
|
rt->rt_expire = time.tv_sec + arpt_keep;
|
|
rt->rt_flags &= ~RTF_REJECT;
|
|
la->la_asked = 0;
|
|
if (la->la_hold) {
|
|
(*ac->ac_if.if_output)(&ac->ac_if, la->la_hold,
|
|
rt_key(rt), rt);
|
|
la->la_hold = 0;
|
|
}
|
|
}
|
|
reply:
|
|
if (op != ARPOP_REQUEST) {
|
|
out:
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
if (itaddr.s_addr == myaddr.s_addr) {
|
|
/* I am the target */
|
|
bcopy((caddr_t)ea->arp_sha, (caddr_t)ea->arp_tha,
|
|
sizeof(ea->arp_sha));
|
|
bcopy((caddr_t)ac->ac_enaddr, (caddr_t)ea->arp_sha,
|
|
sizeof(ea->arp_sha));
|
|
} else {
|
|
la = arplookup(itaddr.s_addr, 0, SIN_PROXY);
|
|
if (la == NULL) {
|
|
#ifdef ARP_PROXYALL
|
|
struct sockaddr_in sin;
|
|
|
|
if(!arp_proxyall) goto out;
|
|
|
|
bzero(&sin, sizeof sin);
|
|
sin.sin_family = AF_INET;
|
|
sin.sin_len = sizeof sin;
|
|
sin.sin_addr = itaddr;
|
|
|
|
rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL);
|
|
if( !rt )
|
|
goto out;
|
|
/*
|
|
* Don't send proxies for nodes on the same interface
|
|
* as this one came out of, or we'll get into a fight
|
|
* over who claims what Ether address.
|
|
*/
|
|
if(rt->rt_ifp == &ac->ac_if) {
|
|
rtfree(rt);
|
|
goto out;
|
|
}
|
|
bcopy((caddr_t)ea->arp_sha, (caddr_t)ea->arp_tha,
|
|
sizeof(ea->arp_sha));
|
|
bcopy(ac->ac_enaddr, (caddr_t)ea->arp_sha,
|
|
sizeof(ea->arp_sha));
|
|
rtfree(rt);
|
|
#ifdef DEBUG_PROXY
|
|
printf("arp: proxying for %s\n",
|
|
arp_ntoa(&itaddr));
|
|
#endif
|
|
#else
|
|
goto out;
|
|
#endif
|
|
} else {
|
|
rt = la->la_rt;
|
|
bcopy((caddr_t)ea->arp_sha, (caddr_t)ea->arp_tha,
|
|
sizeof(ea->arp_sha));
|
|
sdl = SDL(rt->rt_gateway);
|
|
bcopy(LLADDR(sdl), (caddr_t)ea->arp_sha,
|
|
sizeof(ea->arp_sha));
|
|
}
|
|
}
|
|
|
|
bcopy((caddr_t)ea->arp_spa, (caddr_t)ea->arp_tpa, sizeof(ea->arp_spa));
|
|
bcopy((caddr_t)&itaddr, (caddr_t)ea->arp_spa, sizeof(ea->arp_spa));
|
|
ea->arp_op = htons(ARPOP_REPLY);
|
|
ea->arp_pro = htons(ETHERTYPE_IP); /* let's be sure! */
|
|
eh = (struct ether_header *)sa.sa_data;
|
|
bcopy((caddr_t)ea->arp_tha, (caddr_t)eh->ether_dhost,
|
|
sizeof(eh->ether_dhost));
|
|
eh->ether_type = ETHERTYPE_ARP;
|
|
sa.sa_family = AF_UNSPEC;
|
|
sa.sa_len = sizeof(sa);
|
|
(*ac->ac_if.if_output)(&ac->ac_if, m, &sa, (struct rtentry *)0);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Free an arp entry.
|
|
*/
|
|
static void
|
|
arptfree(la)
|
|
register struct llinfo_arp *la;
|
|
{
|
|
register struct rtentry *rt = la->la_rt;
|
|
register struct sockaddr_dl *sdl;
|
|
if (rt == 0)
|
|
panic("arptfree");
|
|
if (rt->rt_refcnt > 0 && (sdl = SDL(rt->rt_gateway)) &&
|
|
sdl->sdl_family == AF_LINK) {
|
|
sdl->sdl_alen = 0;
|
|
la->la_asked = 0;
|
|
rt->rt_flags &= ~RTF_REJECT;
|
|
return;
|
|
}
|
|
rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, rt_mask(rt),
|
|
0, (struct rtentry **)0);
|
|
}
|
|
/*
|
|
* Lookup or enter a new address in arptab.
|
|
*/
|
|
static struct llinfo_arp *
|
|
arplookup(addr, create, proxy)
|
|
u_long addr;
|
|
int create, proxy;
|
|
{
|
|
register struct rtentry *rt;
|
|
static struct sockaddr_inarp sin = {sizeof(sin), AF_INET };
|
|
const char *why = 0;
|
|
|
|
sin.sin_addr.s_addr = addr;
|
|
sin.sin_other = proxy ? SIN_PROXY : 0;
|
|
rt = rtalloc1((struct sockaddr *)&sin, create, 0UL);
|
|
if (rt == 0)
|
|
return (0);
|
|
rt->rt_refcnt--;
|
|
|
|
if(rt->rt_flags & RTF_GATEWAY)
|
|
why = "host is not on local network";
|
|
else if((rt->rt_flags & RTF_LLINFO) == 0)
|
|
why = "could not allocate llinfo";
|
|
else if(rt->rt_gateway->sa_family != AF_LINK)
|
|
why = "gateway route is not ours";
|
|
|
|
if(why && create) {
|
|
log(LOG_DEBUG, "arplookup %s failed: %s\n",
|
|
arp_ntoa(&sin.sin_addr), why);
|
|
return 0;
|
|
} else if(why) {
|
|
return 0;
|
|
}
|
|
return ((struct llinfo_arp *)rt->rt_llinfo);
|
|
}
|
|
|
|
int
|
|
arpioctl(cmd, data)
|
|
int cmd;
|
|
caddr_t data;
|
|
{
|
|
return (EOPNOTSUPP);
|
|
}
|
|
|
|
void
|
|
arp_ifinit(ac, ifa)
|
|
struct arpcom *ac;
|
|
struct ifaddr *ifa;
|
|
{
|
|
ac->ac_ipaddr = IA_SIN(ifa)->sin_addr;
|
|
arpwhohas(ac, &ac->ac_ipaddr);
|
|
ifa->ifa_rtrequest = arp_rtrequest;
|
|
ifa->ifa_flags |= RTF_CLONING;
|
|
}
|