/
route.c
1876 lines (1610 loc) · 45.7 KB
/
route.c
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/* $OpenBSD: route.c,v 1.387 2019/06/24 22:26:25 bluhm Exp $ */
/* $NetBSD: route.c,v 1.14 1996/02/13 22:00:46 christos Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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. Neither the name of the project 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 PROJECT 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 PROJECT 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.
*/
/*
* Copyright (c) 1980, 1986, 1991, 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. 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.
*
* @(#)route.c 8.2 (Berkeley) 11/15/93
*/
/*
* @(#)COPYRIGHT 1.1 (NRL) 17 January 1995
*
* NRL grants permission for redistribution and use in source and binary
* forms, with or without modification, of the software and documentation
* created at NRL 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 acknowledgements:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* This product includes software developed at the Information
* Technology Division, US Naval Research Laboratory.
* 4. Neither the name of the NRL nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THE SOFTWARE PROVIDED BY NRL IS PROVIDED BY NRL 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 NRL 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.
*
* The views and conclusions contained in the software and documentation
* are those of the authors and should not be interpreted as representing
* official policies, either expressed or implied, of the US Naval
* Research Laboratory (NRL).
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/timeout.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <sys/queue.h>
#include <sys/pool.h>
#include <sys/atomic.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/ip_var.h>
#include <netinet/in_var.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_var.h>
#endif
#ifdef MPLS
#include <netmpls/mpls.h>
#endif
#ifdef BFD
#include <net/bfd.h>
#endif
#define ROUNDUP(a) (a>0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
/* Give some jitter to hash, to avoid synchronization between routers. */
static uint32_t rt_hashjitter;
extern unsigned int rtmap_limit;
struct cpumem * rtcounters;
int rttrash; /* routes not in table but not freed */
int ifatrash; /* ifas not in ifp list but not free */
struct pool rtentry_pool; /* pool for rtentry structures */
struct pool rttimer_pool; /* pool for rttimer structures */
void rt_timer_init(void);
int rt_setgwroute(struct rtentry *, u_int);
void rt_putgwroute(struct rtentry *);
int rtflushclone1(struct rtentry *, void *, u_int);
int rtflushclone(struct rtentry *, unsigned int);
int rt_ifa_purge_walker(struct rtentry *, void *, unsigned int);
struct rtentry *rt_match(struct sockaddr *, uint32_t *, int, unsigned int);
int rt_clone(struct rtentry **, struct sockaddr *, unsigned int);
struct sockaddr *rt_plentosa(sa_family_t, int, struct sockaddr_in6 *);
static int rt_copysa(struct sockaddr *, struct sockaddr *, struct sockaddr **);
#ifdef DDB
void db_print_sa(struct sockaddr *);
void db_print_ifa(struct ifaddr *);
int db_show_rtentry(struct rtentry *, void *, unsigned int);
#endif
#define LABELID_MAX 50000
struct rt_label {
TAILQ_ENTRY(rt_label) rtl_entry;
char rtl_name[RTLABEL_LEN];
u_int16_t rtl_id;
int rtl_ref;
};
TAILQ_HEAD(rt_labels, rt_label) rt_labels = TAILQ_HEAD_INITIALIZER(rt_labels);
void
route_init(void)
{
rtcounters = counters_alloc(rts_ncounters);
pool_init(&rtentry_pool, sizeof(struct rtentry), 0, IPL_SOFTNET, 0,
"rtentry", NULL);
while (rt_hashjitter == 0)
rt_hashjitter = arc4random();
#ifdef BFD
bfdinit();
#endif
}
/*
* Returns 1 if the (cached) ``rt'' entry is still valid, 0 otherwise.
*/
int
rtisvalid(struct rtentry *rt)
{
if (rt == NULL)
return (0);
if (!ISSET(rt->rt_flags, RTF_UP))
return (0);
if (ISSET(rt->rt_flags, RTF_GATEWAY)) {
KASSERT(rt->rt_gwroute != NULL);
KASSERT(!ISSET(rt->rt_gwroute->rt_flags, RTF_GATEWAY));
if (!ISSET(rt->rt_gwroute->rt_flags, RTF_UP))
return (0);
}
return (1);
}
/*
* Do the actual lookup for rtalloc(9), do not use directly!
*
* Return the best matching entry for the destination ``dst''.
*
* "RT_RESOLVE" means that a corresponding L2 entry should
* be added to the routing table and resolved (via ARP or
* NDP), if it does not exist.
*/
struct rtentry *
rt_match(struct sockaddr *dst, uint32_t *src, int flags, unsigned int tableid)
{
struct rtentry *rt = NULL;
rt = rtable_match(tableid, dst, src);
if (rt == NULL) {
rtstat_inc(rts_unreach);
return (NULL);
}
if (ISSET(rt->rt_flags, RTF_CLONING) && ISSET(flags, RT_RESOLVE))
rt_clone(&rt, dst, tableid);
rt->rt_use++;
return (rt);
}
int
rt_clone(struct rtentry **rtp, struct sockaddr *dst, unsigned int rtableid)
{
struct rt_addrinfo info;
struct rtentry *rt = *rtp;
int error = 0;
memset(&info, 0, sizeof(info));
info.rti_info[RTAX_DST] = dst;
/*
* The priority of cloned route should be different
* to avoid conflict with /32 cloning routes.
*
* It should also be higher to let the ARP layer find
* cloned routes instead of the cloning one.
*/
KERNEL_LOCK();
error = rtrequest(RTM_RESOLVE, &info, rt->rt_priority - 1, &rt,
rtableid);
KERNEL_UNLOCK();
if (error) {
rtm_miss(RTM_MISS, &info, 0, RTP_NONE, 0, error, rtableid);
} else {
/* Inform listeners of the new route */
rtm_send(rt, RTM_ADD, 0, rtableid);
rtfree(*rtp);
*rtp = rt;
}
return (error);
}
/*
* Originated from bridge_hash() in if_bridge.c
*/
#define mix(a, b, c) do { \
a -= b; a -= c; a ^= (c >> 13); \
b -= c; b -= a; b ^= (a << 8); \
c -= a; c -= b; c ^= (b >> 13); \
a -= b; a -= c; a ^= (c >> 12); \
b -= c; b -= a; b ^= (a << 16); \
c -= a; c -= b; c ^= (b >> 5); \
a -= b; a -= c; a ^= (c >> 3); \
b -= c; b -= a; b ^= (a << 10); \
c -= a; c -= b; c ^= (b >> 15); \
} while (0)
int
rt_hash(struct rtentry *rt, struct sockaddr *dst, uint32_t *src)
{
uint32_t a, b, c;
if (src == NULL || !rtisvalid(rt) || !ISSET(rt->rt_flags, RTF_MPATH))
return (-1);
a = b = 0x9e3779b9;
c = rt_hashjitter;
switch (dst->sa_family) {
case AF_INET:
{
struct sockaddr_in *sin;
if (!ipmultipath)
return (-1);
sin = satosin(dst);
a += sin->sin_addr.s_addr;
b += (src != NULL) ? src[0] : 0;
mix(a, b, c);
break;
}
#ifdef INET6
case AF_INET6:
{
struct sockaddr_in6 *sin6;
if (!ip6_multipath)
return (-1);
sin6 = satosin6(dst);
a += sin6->sin6_addr.s6_addr32[0];
b += sin6->sin6_addr.s6_addr32[2];
c += (src != NULL) ? src[0] : 0;
mix(a, b, c);
a += sin6->sin6_addr.s6_addr32[1];
b += sin6->sin6_addr.s6_addr32[3];
c += (src != NULL) ? src[1] : 0;
mix(a, b, c);
a += sin6->sin6_addr.s6_addr32[2];
b += sin6->sin6_addr.s6_addr32[1];
c += (src != NULL) ? src[2] : 0;
mix(a, b, c);
a += sin6->sin6_addr.s6_addr32[3];
b += sin6->sin6_addr.s6_addr32[0];
c += (src != NULL) ? src[3] : 0;
mix(a, b, c);
break;
}
#endif /* INET6 */
}
return (c & 0xffff);
}
/*
* Allocate a route, potentially using multipath to select the peer.
*/
struct rtentry *
rtalloc_mpath(struct sockaddr *dst, uint32_t *src, unsigned int rtableid)
{
return (rt_match(dst, src, RT_RESOLVE, rtableid));
}
/*
* Look in the routing table for the best matching entry for
* ``dst''.
*
* If a route with a gateway is found and its next hop is no
* longer valid, try to cache it.
*/
struct rtentry *
rtalloc(struct sockaddr *dst, int flags, unsigned int rtableid)
{
return (rt_match(dst, NULL, flags, rtableid));
}
/*
* Cache the route entry corresponding to a reachable next hop in
* the gateway entry ``rt''.
*/
int
rt_setgwroute(struct rtentry *rt, u_int rtableid)
{
struct rtentry *prt, *nhrt;
unsigned int rdomain = rtable_l2(rtableid);
int error;
NET_ASSERT_LOCKED();
KASSERT(ISSET(rt->rt_flags, RTF_GATEWAY));
/* If we cannot find a valid next hop bail. */
nhrt = rt_match(rt->rt_gateway, NULL, RT_RESOLVE, rdomain);
if (nhrt == NULL)
return (ENOENT);
/* Next hop entry must be on the same interface. */
if (nhrt->rt_ifidx != rt->rt_ifidx) {
struct sockaddr_in6 sa_mask;
if (!ISSET(nhrt->rt_flags, RTF_LLINFO) ||
!ISSET(nhrt->rt_flags, RTF_CLONED)) {
rtfree(nhrt);
return (EHOSTUNREACH);
}
/*
* We found a L2 entry, so we might have multiple
* RTF_CLONING routes for the same subnet. Query
* the first route of the multipath chain and iterate
* until we find the correct one.
*/
prt = rtable_lookup(rdomain, rt_key(nhrt->rt_parent),
rt_plen2mask(nhrt->rt_parent, &sa_mask), NULL, RTP_ANY);
rtfree(nhrt);
while (prt != NULL && prt->rt_ifidx != rt->rt_ifidx)
prt = rtable_iterate(prt);
/* We found nothing or a non-cloning MPATH route. */
if (prt == NULL || !ISSET(prt->rt_flags, RTF_CLONING)) {
rtfree(prt);
return (EHOSTUNREACH);
}
error = rt_clone(&prt, rt->rt_gateway, rdomain);
if (error) {
rtfree(prt);
return (error);
}
nhrt = prt;
}
/*
* Next hop must be reachable, this also prevents rtentry
* loops for example when rt->rt_gwroute points to rt.
*/
if (ISSET(nhrt->rt_flags, RTF_CLONING|RTF_GATEWAY)) {
rtfree(nhrt);
return (ENETUNREACH);
}
/* Next hop is valid so remove possible old cache. */
rt_putgwroute(rt);
KASSERT(rt->rt_gwroute == NULL);
/*
* If the MTU of next hop is 0, this will reset the MTU of the
* route to run PMTUD again from scratch.
*/
if (!ISSET(rt->rt_locks, RTV_MTU) && (rt->rt_mtu > nhrt->rt_mtu))
rt->rt_mtu = nhrt->rt_mtu;
/*
* To avoid reference counting problems when writting link-layer
* addresses in an outgoing packet, we ensure that the lifetime
* of a cached entry is greater that the bigger lifetime of the
* gateway entries it is pointed by.
*/
nhrt->rt_flags |= RTF_CACHED;
nhrt->rt_cachecnt++;
rt->rt_gwroute = nhrt;
return (0);
}
/*
* Invalidate the cached route entry of the gateway entry ``rt''.
*/
void
rt_putgwroute(struct rtentry *rt)
{
struct rtentry *nhrt = rt->rt_gwroute;
NET_ASSERT_LOCKED();
if (!ISSET(rt->rt_flags, RTF_GATEWAY) || nhrt == NULL)
return;
KASSERT(ISSET(nhrt->rt_flags, RTF_CACHED));
KASSERT(nhrt->rt_cachecnt > 0);
--nhrt->rt_cachecnt;
if (nhrt->rt_cachecnt == 0)
nhrt->rt_flags &= ~RTF_CACHED;
rtfree(rt->rt_gwroute);
rt->rt_gwroute = NULL;
}
void
rtref(struct rtentry *rt)
{
atomic_inc_int(&rt->rt_refcnt);
}
void
rtfree(struct rtentry *rt)
{
int refcnt;
if (rt == NULL)
return;
refcnt = (int)atomic_dec_int_nv(&rt->rt_refcnt);
if (refcnt <= 0) {
KASSERT(!ISSET(rt->rt_flags, RTF_UP));
KASSERT(!RT_ROOT(rt));
atomic_dec_int(&rttrash);
if (refcnt < 0) {
printf("rtfree: %p not freed (neg refs)\n", rt);
return;
}
KERNEL_LOCK();
rt_timer_remove_all(rt);
ifafree(rt->rt_ifa);
rtlabel_unref(rt->rt_labelid);
#ifdef MPLS
rt_mpls_clear(rt);
#endif
free(rt->rt_gateway, M_RTABLE, ROUNDUP(rt->rt_gateway->sa_len));
free(rt_key(rt), M_RTABLE, rt_key(rt)->sa_len);
KERNEL_UNLOCK();
pool_put(&rtentry_pool, rt);
}
}
void
ifafree(struct ifaddr *ifa)
{
if (ifa == NULL)
panic("ifafree");
if (ifa->ifa_refcnt == 0) {
ifatrash--;
free(ifa, M_IFADDR, 0);
} else
ifa->ifa_refcnt--;
}
/*
* Force a routing table entry to the specified
* destination to go through the given gateway.
* Normally called as a result of a routing redirect
* message from the network layer.
*/
void
rtredirect(struct sockaddr *dst, struct sockaddr *gateway,
struct sockaddr *src, struct rtentry **rtp, unsigned int rdomain)
{
struct rtentry *rt;
int error = 0;
enum rtstat_counters stat = rts_ncounters;
struct rt_addrinfo info;
struct ifaddr *ifa;
unsigned int ifidx = 0;
int flags = RTF_GATEWAY|RTF_HOST;
uint8_t prio = RTP_NONE;
NET_ASSERT_LOCKED();
/* verify the gateway is directly reachable */
rt = rtalloc(gateway, 0, rdomain);
if (!rtisvalid(rt) || ISSET(rt->rt_flags, RTF_GATEWAY)) {
rtfree(rt);
error = ENETUNREACH;
goto out;
}
ifidx = rt->rt_ifidx;
ifa = rt->rt_ifa;
rtfree(rt);
rt = NULL;
rt = rtable_lookup(rdomain, dst, NULL, NULL, RTP_ANY);
/*
* If the redirect isn't from our current router for this dst,
* it's either old or wrong. If it redirects us to ourselves,
* we have a routing loop, perhaps as a result of an interface
* going down recently.
*/
#define equal(a1, a2) \
((a1)->sa_len == (a2)->sa_len && \
bcmp((caddr_t)(a1), (caddr_t)(a2), (a1)->sa_len) == 0)
if (rt != NULL && (!equal(src, rt->rt_gateway) || rt->rt_ifa != ifa))
error = EINVAL;
else if (ifa_ifwithaddr(gateway, rdomain) != NULL ||
(gateway->sa_family = AF_INET &&
in_broadcast(satosin(gateway)->sin_addr, rdomain)))
error = EHOSTUNREACH;
if (error)
goto done;
/*
* Create a new entry if we just got back a wildcard entry
* or the lookup failed. This is necessary for hosts
* which use routing redirects generated by smart gateways
* to dynamically build the routing tables.
*/
if (rt == NULL)
goto create;
/*
* Don't listen to the redirect if it's
* for a route to an interface.
*/
if (ISSET(rt->rt_flags, RTF_GATEWAY)) {
if (!ISSET(rt->rt_flags, RTF_HOST)) {
/*
* Changing from route to net => route to host.
* Create new route, rather than smashing route to net.
*/
create:
rtfree(rt);
flags |= RTF_DYNAMIC;
bzero(&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_ifa = ifa;
info.rti_flags = flags;
rt = NULL;
error = rtrequest(RTM_ADD, &info, RTP_DEFAULT, &rt,
rdomain);
if (error == 0) {
flags = rt->rt_flags;
prio = rt->rt_priority;
}
stat = rts_dynamic;
} else {
/*
* Smash the current notion of the gateway to
* this destination. Should check about netmask!!!
*/
rt->rt_flags |= RTF_MODIFIED;
flags |= RTF_MODIFIED;
prio = rt->rt_priority;
stat = rts_newgateway;
rt_setgate(rt, gateway, rdomain);
}
} else
error = EHOSTUNREACH;
done:
if (rt) {
if (rtp && !error)
*rtp = rt;
else
rtfree(rt);
}
out:
if (error)
rtstat_inc(rts_badredirect);
else if (stat != rts_ncounters)
rtstat_inc(stat);
bzero((caddr_t)&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_info[RTAX_AUTHOR] = src;
rtm_miss(RTM_REDIRECT, &info, flags, prio, ifidx, error, rdomain);
}
/*
* Delete a route and generate a message
*/
int
rtdeletemsg(struct rtentry *rt, struct ifnet *ifp, u_int tableid)
{
int error;
struct rt_addrinfo info;
struct sockaddr_in6 sa_mask;
KASSERT(rt->rt_ifidx == ifp->if_index);
/*
* Request the new route so that the entry is not actually
* deleted. That will allow the information being reported to
* be accurate (and consistent with route_output()).
*/
memset(&info, 0, sizeof(info));
info.rti_info[RTAX_DST] = rt_key(rt);
info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
if (!ISSET(rt->rt_flags, RTF_HOST))
info.rti_info[RTAX_NETMASK] = rt_plen2mask(rt, &sa_mask);
error = rtrequest_delete(&info, rt->rt_priority, ifp, &rt, tableid);
rtm_send(rt, RTM_DELETE, error, tableid);
if (error == 0)
rtfree(rt);
return (error);
}
static inline int
rtequal(struct rtentry *a, struct rtentry *b)
{
if (a == b)
return 1;
if (memcmp(rt_key(a), rt_key(b), rt_key(a)->sa_len) == 0 &&
rt_plen(a) == rt_plen(b))
return 1;
else
return 0;
}
int
rtflushclone1(struct rtentry *rt, void *arg, u_int id)
{
struct rtentry *cloningrt = arg;
struct ifnet *ifp;
if (!ISSET(rt->rt_flags, RTF_CLONED))
return 0;
/* Cached route must stay alive as long as their parent are alive. */
if (ISSET(rt->rt_flags, RTF_CACHED) && (rt->rt_parent != cloningrt))
return 0;
if (!rtequal(rt->rt_parent, cloningrt))
return 0;
/*
* This happens when an interface with a RTF_CLONING route is
* being detached. In this case it's safe to bail because all
* the routes are being purged by rt_ifa_purge().
*/
ifp = if_get(rt->rt_ifidx);
if (ifp == NULL)
return 0;
if_put(ifp);
return EEXIST;
}
int
rtflushclone(struct rtentry *parent, unsigned int rtableid)
{
struct rtentry *rt = NULL;
struct ifnet *ifp;
int error;
#ifdef DIAGNOSTIC
if (!parent || (parent->rt_flags & RTF_CLONING) == 0)
panic("rtflushclone: called with a non-cloning route");
#endif
do {
error = rtable_walk(rtableid, rt_key(parent)->sa_family, &rt,
rtflushclone1, parent);
if (rt != NULL && error == EEXIST) {
ifp = if_get(rt->rt_ifidx);
if (ifp == NULL) {
error = EAGAIN;
} else {
error = rtdeletemsg(rt, ifp, rtableid);
if (error == 0)
error = EAGAIN;
if_put(ifp);
}
}
rtfree(rt);
rt = NULL;
} while (error == EAGAIN);
return error;
}
int
rtrequest_delete(struct rt_addrinfo *info, u_int8_t prio, struct ifnet *ifp,
struct rtentry **ret_nrt, u_int tableid)
{
struct rtentry *rt;
int error;
NET_ASSERT_LOCKED();
if (!rtable_exists(tableid))
return (EAFNOSUPPORT);
rt = rtable_lookup(tableid, info->rti_info[RTAX_DST],
info->rti_info[RTAX_NETMASK], info->rti_info[RTAX_GATEWAY], prio);
if (rt == NULL)
return (ESRCH);
/* Make sure that's the route the caller want to delete. */
if (ifp != NULL && ifp->if_index != rt->rt_ifidx) {
rtfree(rt);
return (ESRCH);
}
#ifdef BFD
if (ISSET(rt->rt_flags, RTF_BFD))
bfdclear(rt);
#endif
error = rtable_delete(tableid, info->rti_info[RTAX_DST],
info->rti_info[RTAX_NETMASK], rt);
if (error != 0) {
rtfree(rt);
return (ESRCH);
}
/* Release next hop cache before flushing cloned entries. */
rt_putgwroute(rt);
/* Clean up any cloned children. */
if (ISSET(rt->rt_flags, RTF_CLONING))
rtflushclone(rt, tableid);
rtfree(rt->rt_parent);
rt->rt_parent = NULL;
rt->rt_flags &= ~RTF_UP;
KASSERT(ifp->if_index == rt->rt_ifidx);
ifp->if_rtrequest(ifp, RTM_DELETE, rt);
atomic_inc_int(&rttrash);
if (ret_nrt != NULL)
*ret_nrt = rt;
else
rtfree(rt);
return (0);
}
int
rtrequest(int req, struct rt_addrinfo *info, u_int8_t prio,
struct rtentry **ret_nrt, u_int tableid)
{
struct ifnet *ifp;
struct rtentry *rt, *crt;
struct ifaddr *ifa;
struct sockaddr *ndst;
struct sockaddr_rtlabel *sa_rl, sa_rl2;
struct sockaddr_dl sa_dl = { sizeof(sa_dl), AF_LINK };
int error;
NET_ASSERT_LOCKED();
if (!rtable_exists(tableid))
return (EAFNOSUPPORT);
if (info->rti_flags & RTF_HOST)
info->rti_info[RTAX_NETMASK] = NULL;
switch (req) {
case RTM_DELETE:
return (EINVAL);
case RTM_RESOLVE:
if (ret_nrt == NULL || (rt = *ret_nrt) == NULL)
return (EINVAL);
if ((rt->rt_flags & RTF_CLONING) == 0)
return (EINVAL);
KASSERT(rt->rt_ifa->ifa_ifp != NULL);
info->rti_ifa = rt->rt_ifa;
info->rti_flags = rt->rt_flags | (RTF_CLONED|RTF_HOST);
info->rti_flags &= ~(RTF_CLONING|RTF_CONNECTED|RTF_STATIC);
info->rti_info[RTAX_GATEWAY] = sdltosa(&sa_dl);
info->rti_info[RTAX_LABEL] =
rtlabel_id2sa(rt->rt_labelid, &sa_rl2);
/* FALLTHROUGH */
case RTM_ADD:
if (info->rti_ifa == NULL)
return (EINVAL);
ifa = info->rti_ifa;
ifp = ifa->ifa_ifp;
if (prio == 0)
prio = ifp->if_priority + RTP_STATIC;
error = rt_copysa(info->rti_info[RTAX_DST],
info->rti_info[RTAX_NETMASK], &ndst);
if (error)
return (error);
rt = pool_get(&rtentry_pool, PR_NOWAIT | PR_ZERO);
if (rt == NULL) {
free(ndst, M_RTABLE, ndst->sa_len);
return (ENOBUFS);
}
rt->rt_refcnt = 1;
rt->rt_flags = info->rti_flags | RTF_UP;
rt->rt_priority = prio; /* init routing priority */
LIST_INIT(&rt->rt_timer);
/* Check the link state if the table supports it. */
if (rtable_mpath_capable(tableid, ndst->sa_family) &&
!ISSET(rt->rt_flags, RTF_LOCAL) &&
(!LINK_STATE_IS_UP(ifp->if_link_state) ||
!ISSET(ifp->if_flags, IFF_UP))) {
rt->rt_flags &= ~RTF_UP;
rt->rt_priority |= RTP_DOWN;
}
if (info->rti_info[RTAX_LABEL] != NULL) {
sa_rl = (struct sockaddr_rtlabel *)
info->rti_info[RTAX_LABEL];
rt->rt_labelid = rtlabel_name2id(sa_rl->sr_label);
}
#ifdef MPLS
/* We have to allocate additional space for MPLS infos */
if (info->rti_flags & RTF_MPLS &&
(info->rti_info[RTAX_SRC] != NULL ||
info->rti_info[RTAX_DST]->sa_family == AF_MPLS)) {
error = rt_mpls_set(rt, info->rti_info[RTAX_SRC],
info->rti_mpls);
if (error) {
free(ndst, M_RTABLE, ndst->sa_len);
pool_put(&rtentry_pool, rt);
return (error);
}
} else
rt_mpls_clear(rt);
#endif
ifa->ifa_refcnt++;
rt->rt_ifa = ifa;
rt->rt_ifidx = ifp->if_index;
/*
* Copy metrics and a back pointer from the cloned
* route's parent.
*/
if (ISSET(rt->rt_flags, RTF_CLONED)) {
rtref(*ret_nrt);
rt->rt_parent = *ret_nrt;
rt->rt_rmx = (*ret_nrt)->rt_rmx;
}
/*
* We must set rt->rt_gateway before adding ``rt'' to
* the routing table because the radix MPATH code use
* it to (re)order routes.
*/
if ((error = rt_setgate(rt, info->rti_info[RTAX_GATEWAY],
tableid))) {
ifafree(ifa);
rtfree(rt->rt_parent);
rt_putgwroute(rt);
free(rt->rt_gateway, M_RTABLE, 0);
free(ndst, M_RTABLE, ndst->sa_len);
pool_put(&rtentry_pool, rt);
return (error);
}
error = rtable_insert(tableid, ndst,
info->rti_info[RTAX_NETMASK], info->rti_info[RTAX_GATEWAY],
rt->rt_priority, rt);
if (error != 0 &&
(crt = rtable_match(tableid, ndst, NULL)) != NULL) {
/* overwrite cloned route */
if (ISSET(crt->rt_flags, RTF_CLONED)) {
struct ifnet *cifp;
cifp = if_get(crt->rt_ifidx);
KASSERT(cifp != NULL);
rtdeletemsg(crt, cifp, tableid);
if_put(cifp);
error = rtable_insert(tableid, ndst,
info->rti_info[RTAX_NETMASK],
info->rti_info[RTAX_GATEWAY],
rt->rt_priority, rt);
}
rtfree(crt);
}
if (error != 0) {
ifafree(ifa);
rtfree(rt->rt_parent);
rt_putgwroute(rt);
free(rt->rt_gateway, M_RTABLE, 0);
free(ndst, M_RTABLE, ndst->sa_len);
pool_put(&rtentry_pool, rt);
return (EEXIST);
}
ifp->if_rtrequest(ifp, req, rt);
if_group_routechange(info->rti_info[RTAX_DST],
info->rti_info[RTAX_NETMASK]);
if (ret_nrt != NULL)
*ret_nrt = rt;
else
rtfree(rt);
break;
}
return (0);
}
int
rt_setgate(struct rtentry *rt, struct sockaddr *gate, u_int rtableid)
{
int glen = ROUNDUP(gate->sa_len);
struct sockaddr *sa;
if (rt->rt_gateway == NULL || glen != ROUNDUP(rt->rt_gateway->sa_len)) {
sa = malloc(glen, M_RTABLE, M_NOWAIT);
if (sa == NULL)
return (ENOBUFS);
if (rt->rt_gateway != NULL) {
free(rt->rt_gateway, M_RTABLE,
ROUNDUP(rt->rt_gateway->sa_len));
}
rt->rt_gateway = sa;