freebsd-dev/sys/net/if_llatbl.c

352 lines
8.2 KiB
C

/*
* Copyright (c) 2004 Luigi Rizzo, Alessandro Cerri. All rights reserved.
* Copyright (c) 2004-2008 Qing Li. All rights reserved.
* Copyright (c) 2008 Kip Macy. 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.
*
* THIS SOFTWARE IS PROVIDED BY AUTHOR 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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/syslog.h>
#include <sys/sysctl.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/rwlock.h>
#include <sys/vimage.h>
#include <vm/uma.h>
#include <netinet/in.h>
#include <net/if_llatbl.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_var.h>
#include <net/route.h>
#include <netinet/if_ether.h>
#include <netinet6/in6_var.h>
#include <netinet6/nd6.h>
MALLOC_DEFINE(M_LLTABLE, "lltable", "link level address tables");
static SLIST_HEAD(, lltable) lltables = SLIST_HEAD_INITIALIZER(lltables);
extern void arprequest(struct ifnet *, struct in_addr *, struct in_addr *,
u_char *);
/*
* Dump arp state for a specific address family.
*/
int
lltable_sysctl_dumparp(int af, struct sysctl_req *wr)
{
struct lltable *llt;
int error = 0;
IFNET_RLOCK();
SLIST_FOREACH(llt, &lltables, llt_link) {
if (llt->llt_af == af) {
error = llt->llt_dump(llt, wr);
if (error != 0)
goto done;
}
}
done:
IFNET_RUNLOCK();
return (error);
}
/*
* Deletes an address from the address table.
* This function is called by the timer functions
* such as arptimer() and nd6_llinfo_timer(), and
* the caller does the locking.
*/
void
llentry_free(struct llentry *lle)
{
LLE_WLOCK_ASSERT(lle);
LIST_REMOVE(lle, lle_next);
if (lle->la_hold != NULL)
m_freem(lle->la_hold);
LLE_FREE_LOCKED(lle);
}
/*
* Update an llentry for address dst (equivalent to rtalloc for new-arp)
* Caller must pass in a valid struct llentry *
*
* if found the llentry * is returned referenced and unlocked
*/
int
llentry_update(struct llentry **llep, struct lltable *lt,
struct sockaddr *dst, struct ifnet *ifp)
{
struct llentry *la;
IF_AFDATA_RLOCK(ifp);
la = lla_lookup(lt, LLE_EXCLUSIVE,
(struct sockaddr *)dst);
IF_AFDATA_RUNLOCK(ifp);
if ((la == NULL) &&
(ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) == 0) {
IF_AFDATA_WLOCK(ifp);
la = lla_lookup(lt,
(LLE_CREATE | LLE_EXCLUSIVE),
(struct sockaddr *)dst);
IF_AFDATA_WUNLOCK(ifp);
}
if (la != NULL && (*llep != la)) {
if (*llep != NULL)
LLE_FREE(*llep);
LLE_ADDREF(la);
LLE_WUNLOCK(la);
*llep = la;
} else if (la != NULL)
LLE_WUNLOCK(la);
if (la == NULL)
return (ENOENT);
return (0);
}
/*
* Free all entries from given table and free itself.
* Since lltables collects from all of the intefaces,
* the caller of this function must acquire IFNET_WLOCK().
*/
void
lltable_free(struct lltable *llt)
{
struct llentry *lle, *next;
int i;
KASSERT(llt != NULL, ("%s: llt is NULL", __func__));
IFNET_WLOCK();
SLIST_REMOVE(&lltables, llt, lltable, llt_link);
IFNET_WUNLOCK();
for (i=0; i < LLTBL_HASHTBL_SIZE; i++) {
LIST_FOREACH_SAFE(lle, &llt->lle_head[i], lle_next, next) {
callout_drain(&lle->la_timer);
LLE_WLOCK(lle);
llentry_free(lle);
}
}
free(llt, M_LLTABLE);
}
void
lltable_drain(int af)
{
struct lltable *llt;
struct llentry *lle;
register int i;
IFNET_RLOCK();
SLIST_FOREACH(llt, &lltables, llt_link) {
if (llt->llt_af != af)
continue;
for (i=0; i < LLTBL_HASHTBL_SIZE; i++) {
LIST_FOREACH(lle, &llt->lle_head[i], lle_next) {
if (lle->la_hold) {
m_freem(lle->la_hold);
lle->la_hold = NULL;
}
}
}
}
IFNET_RUNLOCK();
}
/*
* Create a new lltable.
*/
struct lltable *
lltable_init(struct ifnet *ifp, int af)
{
struct lltable *llt;
register int i;
llt = malloc(sizeof(struct lltable), M_LLTABLE, M_WAITOK);
if (llt == NULL)
return (NULL);
llt->llt_af = af;
llt->llt_ifp = ifp;
for (i = 0; i < LLTBL_HASHTBL_SIZE; i++)
LIST_INIT(&llt->lle_head[i]);
IFNET_WLOCK();
SLIST_INSERT_HEAD(&lltables, llt, llt_link);
IFNET_WUNLOCK();
return (llt);
}
/*
* Called in route_output when adding/deleting a route to an interface.
*/
int
lla_rt_output(struct rt_msghdr *rtm, struct rt_addrinfo *info)
{
struct sockaddr_dl *dl =
(struct sockaddr_dl *)info->rti_info[RTAX_GATEWAY];
struct sockaddr *dst = (struct sockaddr *)info->rti_info[RTAX_DST];
struct ifnet *ifp;
struct lltable *llt;
struct llentry *lle;
u_int laflags = 0, flags = 0;
int error = 0;
if (dl == NULL || dl->sdl_family != AF_LINK) {
log(LOG_INFO, "%s: invalid dl\n", __func__);
return EINVAL;
}
ifp = ifnet_byindex(dl->sdl_index);
if (ifp == NULL) {
log(LOG_INFO, "%s: invalid ifp (sdl_index %d)\n",
__func__, dl->sdl_index);
return EINVAL;
}
switch (rtm->rtm_type) {
case RTM_ADD:
if (rtm->rtm_flags & RTF_ANNOUNCE) {
flags |= LLE_PUB;
#ifdef INET
if (dst->sa_family == AF_INET &&
((struct sockaddr_inarp *)dst)->sin_other != 0) {
struct rtentry *rt = rtalloc1(dst, 0, 0);
if (rt == NULL || !(rt->rt_flags & RTF_HOST)) {
log(LOG_INFO, "%s: RTM_ADD publish "
"(proxy only) is invalid\n",
__func__);
if (rt)
RTFREE_LOCKED(rt);
return EINVAL;
}
RTFREE_LOCKED(rt);
flags |= LLE_PROXY;
}
#endif
}
flags |= LLE_CREATE;
break;
case RTM_DELETE:
flags |= LLE_DELETE;
break;
case RTM_CHANGE:
break;
default:
return EINVAL; /* XXX not implemented yet */
}
/* XXX linked list may be too expensive */
IFNET_RLOCK();
SLIST_FOREACH(llt, &lltables, llt_link) {
if (llt->llt_af == dst->sa_family &&
llt->llt_ifp == ifp)
break;
}
IFNET_RUNLOCK();
KASSERT(llt != NULL, ("Yep, ugly hacks are bad\n"));
if (flags && LLE_CREATE)
flags |= LLE_EXCLUSIVE;
IF_AFDATA_LOCK(ifp);
lle = lla_lookup(llt, flags, dst);
IF_AFDATA_UNLOCK(ifp);
if (LLE_IS_VALID(lle)) {
if (flags & LLE_CREATE) {
/*
* If we delay the delete, then a subsequent
* "arp add" should look up this entry, reset the
* LLE_DELETED flag, and reset the expiration timer
*/
bcopy(LLADDR(dl), &lle->ll_addr, ifp->if_addrlen);
lle->la_flags |= LLE_VALID;
lle->la_flags &= ~LLE_DELETED;
#ifdef INET6
/*
* ND6
*/
if (dst->sa_family == AF_INET6)
lle->ln_state = ND6_LLINFO_REACHABLE;
#endif
/*
* NB: arp and ndp always set (RTF_STATIC | RTF_HOST)
*/
if (rtm->rtm_rmx.rmx_expire == 0) {
lle->la_flags |= LLE_STATIC;
lle->la_expire = 0;
} else
lle->la_expire = rtm->rtm_rmx.rmx_expire;
laflags = lle->la_flags;
LLE_WUNLOCK(lle);
#ifdef INET
/* gratuitous ARP */
if ((laflags & LLE_PUB) && dst->sa_family == AF_INET) {
arprequest(ifp,
&((struct sockaddr_in *)dst)->sin_addr,
&((struct sockaddr_in *)dst)->sin_addr,
((laflags & LLE_PROXY) ?
(u_char *)IF_LLADDR(ifp) :
(u_char *)LLADDR(dl)));
}
#endif
} else {
if (flags & LLE_EXCLUSIVE)
LLE_WUNLOCK(lle);
else
LLE_RUNLOCK(lle);
}
} else if ((lle == NULL) && (flags & LLE_DELETE))
error = EINVAL;
return (error);
}