freebsd-dev/sys/net/route.c
Alexander V. Chernikov cb984c62d7 Fix multipath support for rib_lookup_info().
The initial plan was to remove rib_lookup_info() before
 FreeBSD 13. As several customers are still remaining,
 fix rib_lookup_info() for the multipath use case.
2021-01-29 23:14:24 +00:00

771 lines
20 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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 8.3.1.1 (Berkeley) 2/23/95
* $FreeBSD$
*/
/************************************************************************
* Note: In this file a 'fib' is a "forwarding information base" *
* Which is the new name for an in kernel routing (next hop) table. *
***********************************************************************/
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_mrouting.h"
#include "opt_route.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/sysproto.h>
#include <sys/proc.h>
#include <sys/domain.h>
#include <sys/eventhandler.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/rmlock.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/route/route_ctl.h>
#include <net/route/route_var.h>
#include <net/route/nhop.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/ip_mroute.h>
VNET_PCPUSTAT_DEFINE(struct rtstat, rtstat);
VNET_PCPUSTAT_SYSINIT(rtstat);
#ifdef VIMAGE
VNET_PCPUSTAT_SYSUNINIT(rtstat);
#endif
EVENTHANDLER_LIST_DEFINE(rt_addrmsg);
static int rt_ifdelroute(const struct rtentry *rt, const struct nhop_object *,
void *arg);
static int rt_exportinfo(struct rtentry *rt, struct nhop_object *nh,
struct rt_addrinfo *info, int flags);
/*
* route initialization must occur before ip6_init2(), which happenas at
* SI_ORDER_MIDDLE.
*/
static void
route_init(void)
{
nhops_init();
}
SYSINIT(route_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, NULL);
struct rib_head *
rt_table_init(int offset, int family, u_int fibnum)
{
struct rib_head *rh;
rh = malloc(sizeof(struct rib_head), M_RTABLE, M_WAITOK | M_ZERO);
/* TODO: These details should be hidded inside radix.c */
/* Init masks tree */
rn_inithead_internal(&rh->head, rh->rnh_nodes, offset);
rn_inithead_internal(&rh->rmhead.head, rh->rmhead.mask_nodes, 0);
rh->head.rnh_masks = &rh->rmhead;
/* Save metadata associated with this routing table. */
rh->rib_family = family;
rh->rib_fibnum = fibnum;
#ifdef VIMAGE
rh->rib_vnet = curvnet;
#endif
tmproutes_init(rh);
/* Init locks */
RIB_LOCK_INIT(rh);
nhops_init_rib(rh);
/* Init subscription system */
rib_init_subscriptions(rh);
/* Finally, set base callbacks */
rh->rnh_addaddr = rn_addroute;
rh->rnh_deladdr = rn_delete;
rh->rnh_matchaddr = rn_match;
rh->rnh_lookup = rn_lookup;
rh->rnh_walktree = rn_walktree;
rh->rnh_walktree_from = rn_walktree_from;
return (rh);
}
static int
rt_freeentry(struct radix_node *rn, void *arg)
{
struct radix_head * const rnh = arg;
struct radix_node *x;
x = (struct radix_node *)rn_delete(rn + 2, NULL, rnh);
if (x != NULL)
R_Free(x);
return (0);
}
void
rt_table_destroy(struct rib_head *rh)
{
RIB_WLOCK(rh);
rh->rib_dying = true;
RIB_WUNLOCK(rh);
#ifdef FIB_ALGO
fib_destroy_rib(rh);
#endif
tmproutes_destroy(rh);
rn_walktree(&rh->rmhead.head, rt_freeentry, &rh->rmhead.head);
nhops_destroy_rib(rh);
rib_destroy_subscriptions(rh);
/* Assume table is already empty */
RIB_LOCK_DESTROY(rh);
free(rh, M_RTABLE);
}
/*
* Adds a temporal redirect entry to the routing table.
* @fibnum: fib number
* @dst: destination to install redirect to
* @gateway: gateway to go via
* @author: sockaddr of originating router, can be NULL
* @ifp: interface to use for the redirected route
* @flags: set of flags to add. Allowed: RTF_GATEWAY
* @lifetime_sec: time in seconds to expire this redirect.
*
* Retuns 0 on success, errno otherwise.
*/
int
rib_add_redirect(u_int fibnum, struct sockaddr *dst, struct sockaddr *gateway,
struct sockaddr *author, struct ifnet *ifp, int flags, int lifetime_sec)
{
struct rib_cmd_info rc;
int error;
struct rt_addrinfo info;
struct rt_metrics rti_rmx;
struct ifaddr *ifa;
NET_EPOCH_ASSERT();
if (rt_tables_get_rnh(fibnum, dst->sa_family) == NULL)
return (EAFNOSUPPORT);
/* Verify the allowed flag mask. */
KASSERT(((flags & ~(RTF_GATEWAY)) == 0),
("invalid redirect flags: %x", flags));
flags |= RTF_HOST | RTF_DYNAMIC;
/* Get the best ifa for the given interface and gateway. */
if ((ifa = ifaof_ifpforaddr(gateway, ifp)) == NULL)
return (ENETUNREACH);
ifa_ref(ifa);
bzero(&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_ifa = ifa;
info.rti_ifp = ifp;
info.rti_flags = flags;
/* Setup route metrics to define expire time. */
bzero(&rti_rmx, sizeof(rti_rmx));
/* Set expire time as absolute. */
rti_rmx.rmx_expire = lifetime_sec + time_second;
info.rti_mflags |= RTV_EXPIRE;
info.rti_rmx = &rti_rmx;
error = rib_action(fibnum, RTM_ADD, &info, &rc);
ifa_free(ifa);
if (error != 0) {
/* TODO: add per-fib redirect stats. */
return (error);
}
RTSTAT_INC(rts_dynamic);
/* Send notification of a route addition to userland. */
bzero(&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_info[RTAX_AUTHOR] = author;
rt_missmsg_fib(RTM_REDIRECT, &info, flags | RTF_UP, error, fibnum);
return (0);
}
/*
* Routing table ioctl interface.
*/
int
rtioctl_fib(u_long req, caddr_t data, u_int fibnum)
{
/*
* If more ioctl commands are added here, make sure the proper
* super-user checks are being performed because it is possible for
* prison-root to make it this far if raw sockets have been enabled
* in jails.
*/
#ifdef INET
/* Multicast goop, grrr... */
return mrt_ioctl ? mrt_ioctl(req, data, fibnum) : EOPNOTSUPP;
#else /* INET */
return ENXIO;
#endif /* INET */
}
struct ifaddr *
ifa_ifwithroute(int flags, const struct sockaddr *dst,
const struct sockaddr *gateway, u_int fibnum)
{
struct ifaddr *ifa;
NET_EPOCH_ASSERT();
if ((flags & RTF_GATEWAY) == 0) {
/*
* If we are adding a route to an interface,
* and the interface is a pt to pt link
* we should search for the destination
* as our clue to the interface. Otherwise
* we can use the local address.
*/
ifa = NULL;
if (flags & RTF_HOST)
ifa = ifa_ifwithdstaddr(dst, fibnum);
if (ifa == NULL)
ifa = ifa_ifwithaddr(gateway);
} else {
/*
* If we are adding a route to a remote net
* or host, the gateway may still be on the
* other end of a pt to pt link.
*/
ifa = ifa_ifwithdstaddr(gateway, fibnum);
}
if (ifa == NULL)
ifa = ifa_ifwithnet(gateway, 0, fibnum);
if (ifa == NULL) {
struct nhop_object *nh;
nh = rib_lookup(fibnum, gateway, NHR_NONE, 0);
/*
* dismiss a gateway that is reachable only
* through the default router
*/
if ((nh == NULL) || (nh->nh_flags & NHF_DEFAULT))
return (NULL);
ifa = nh->nh_ifa;
}
if (ifa->ifa_addr->sa_family != dst->sa_family) {
struct ifaddr *oifa = ifa;
ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
if (ifa == NULL)
ifa = oifa;
}
return (ifa);
}
/*
* Copy most of @rt data into @info.
*
* If @flags contains NHR_COPY, copies dst,netmask and gw to the
* pointers specified by @info structure. Assume such pointers
* are zeroed sockaddr-like structures with sa_len field initialized
* to reflect size of the provided buffer. if no NHR_COPY is specified,
* point dst,netmask and gw @info fields to appropriate @rt values.
*
* if @flags contains NHR_REF, do refcouting on rt_ifp and rt_ifa.
*
* Returns 0 on success.
*/
static int
rt_exportinfo(struct rtentry *rt, struct nhop_object *nh,
struct rt_addrinfo *info, int flags)
{
struct rt_metrics *rmx;
struct sockaddr *src, *dst;
int sa_len;
if (flags & NHR_COPY) {
/* Copy destination if dst is non-zero */
src = rt_key(rt);
dst = info->rti_info[RTAX_DST];
sa_len = src->sa_len;
if (dst != NULL) {
if (src->sa_len > dst->sa_len)
return (ENOMEM);
memcpy(dst, src, src->sa_len);
info->rti_addrs |= RTA_DST;
}
/* Copy mask if set && dst is non-zero */
src = rt_mask(rt);
dst = info->rti_info[RTAX_NETMASK];
if (src != NULL && dst != NULL) {
/*
* Radix stores different value in sa_len,
* assume rt_mask() to have the same length
* as rt_key()
*/
if (sa_len > dst->sa_len)
return (ENOMEM);
memcpy(dst, src, src->sa_len);
info->rti_addrs |= RTA_NETMASK;
}
/* Copy gateway is set && dst is non-zero */
src = &nh->gw_sa;
dst = info->rti_info[RTAX_GATEWAY];
if ((nhop_get_rtflags(nh) & RTF_GATEWAY) &&
src != NULL && dst != NULL) {
if (src->sa_len > dst->sa_len)
return (ENOMEM);
memcpy(dst, src, src->sa_len);
info->rti_addrs |= RTA_GATEWAY;
}
} else {
info->rti_info[RTAX_DST] = rt_key(rt);
info->rti_addrs |= RTA_DST;
if (rt_mask(rt) != NULL) {
info->rti_info[RTAX_NETMASK] = rt_mask(rt);
info->rti_addrs |= RTA_NETMASK;
}
if (nhop_get_rtflags(nh) & RTF_GATEWAY) {
info->rti_info[RTAX_GATEWAY] = &nh->gw_sa;
info->rti_addrs |= RTA_GATEWAY;
}
}
rmx = info->rti_rmx;
if (rmx != NULL) {
info->rti_mflags |= RTV_MTU;
rmx->rmx_mtu = nh->nh_mtu;
}
info->rti_flags = rt->rte_flags | nhop_get_rtflags(nh);
info->rti_ifp = nh->nh_ifp;
info->rti_ifa = nh->nh_ifa;
if (flags & NHR_REF) {
if_ref(info->rti_ifp);
ifa_ref(info->rti_ifa);
}
return (0);
}
/*
* Lookups up route entry for @dst in RIB database for fib @fibnum.
* Exports entry data to @info using rt_exportinfo().
*
* If @flags contains NHR_REF, refcouting is performed on rt_ifp and rt_ifa.
* All references can be released later by calling rib_free_info().
*
* Returns 0 on success.
* Returns ENOENT for lookup failure, ENOMEM for export failure.
*/
int
rib_lookup_info(uint32_t fibnum, const struct sockaddr *dst, uint32_t flags,
uint32_t flowid, struct rt_addrinfo *info)
{
RIB_RLOCK_TRACKER;
struct rib_head *rh;
struct radix_node *rn;
struct rtentry *rt;
struct nhop_object *nh;
int error;
KASSERT((fibnum < rt_numfibs), ("rib_lookup_rte: bad fibnum"));
rh = rt_tables_get_rnh(fibnum, dst->sa_family);
if (rh == NULL)
return (ENOENT);
RIB_RLOCK(rh);
rn = rh->rnh_matchaddr(__DECONST(void *, dst), &rh->head);
if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
rt = RNTORT(rn);
nh = nhop_select(rt->rt_nhop, flowid);
/* Ensure route & ifp is UP */
if (RT_LINK_IS_UP(nh->nh_ifp)) {
flags = (flags & NHR_REF) | NHR_COPY;
error = rt_exportinfo(rt, nh, info, flags);
RIB_RUNLOCK(rh);
return (error);
}
}
RIB_RUNLOCK(rh);
return (ENOENT);
}
/*
* Releases all references acquired by rib_lookup_info() when
* called with NHR_REF flags.
*/
void
rib_free_info(struct rt_addrinfo *info)
{
ifa_free(info->rti_ifa);
if_rele(info->rti_ifp);
}
/*
* Delete Routes for a Network Interface
*
* Called for each routing entry via the rnh->rnh_walktree() call above
* to delete all route entries referencing a detaching network interface.
*
* Arguments:
* rt pointer to rtentry
* nh pointer to nhop
* arg argument passed to rnh->rnh_walktree() - detaching interface
*
* Returns:
* 0 successful
* errno failed - reason indicated
*/
static int
rt_ifdelroute(const struct rtentry *rt, const struct nhop_object *nh, void *arg)
{
struct ifnet *ifp = arg;
if (nh->nh_ifp != ifp)
return (0);
/*
* Protect (sorta) against walktree recursion problems
* with cloned routes
*/
if ((rt->rte_flags & RTF_UP) == 0)
return (0);
return (1);
}
/*
* Delete all remaining routes using this interface
* Unfortuneatly the only way to do this is to slog through
* the entire routing table looking for routes which point
* to this interface...oh well...
*/
void
rt_flushifroutes_af(struct ifnet *ifp, int af)
{
KASSERT((af >= 1 && af <= AF_MAX), ("%s: af %d not >= 1 and <= %d",
__func__, af, AF_MAX));
rib_foreach_table_walk_del(af, rt_ifdelroute, ifp);
}
void
rt_flushifroutes(struct ifnet *ifp)
{
rib_foreach_table_walk_del(AF_UNSPEC, rt_ifdelroute, ifp);
}
/*
* Look up rt_addrinfo for a specific fib. Note that if rti_ifa is defined,
* it will be referenced so the caller must free it.
*
* Assume basic consistency checks are executed by callers:
* RTAX_DST exists, if RTF_GATEWAY is set, RTAX_GATEWAY exists as well.
*/
int
rt_getifa_fib(struct rt_addrinfo *info, u_int fibnum)
{
const struct sockaddr *dst, *gateway, *ifpaddr, *ifaaddr;
struct epoch_tracker et;
int needref, error, flags;
dst = info->rti_info[RTAX_DST];
gateway = info->rti_info[RTAX_GATEWAY];
ifpaddr = info->rti_info[RTAX_IFP];
ifaaddr = info->rti_info[RTAX_IFA];
flags = info->rti_flags;
/*
* ifp may be specified by sockaddr_dl
* when protocol address is ambiguous.
*/
error = 0;
needref = (info->rti_ifa == NULL);
NET_EPOCH_ENTER(et);
/* If we have interface specified by the ifindex in the address, use it */
if (info->rti_ifp == NULL && ifpaddr != NULL &&
ifpaddr->sa_family == AF_LINK) {
const struct sockaddr_dl *sdl = (const struct sockaddr_dl *)ifpaddr;
if (sdl->sdl_index != 0)
info->rti_ifp = ifnet_byindex(sdl->sdl_index);
}
/*
* If we have source address specified, try to find it
* TODO: avoid enumerating all ifas on all interfaces.
*/
if (info->rti_ifa == NULL && ifaaddr != NULL)
info->rti_ifa = ifa_ifwithaddr(ifaaddr);
if (info->rti_ifa == NULL) {
const struct sockaddr *sa;
/*
* Most common use case for the userland-supplied routes.
*
* Choose sockaddr to select ifa.
* -- if ifp is set --
* Order of preference:
* 1) IFA address
* 2) gateway address
* Note: for interface routes link-level gateway address
* is specified to indicate the interface index without
* specifying RTF_GATEWAY. In this case, ignore gateway
* Note: gateway AF may be different from dst AF. In this case,
* ignore gateway
* 3) final destination.
* 4) if all of these fails, try to get at least link-level ifa.
* -- else --
* try to lookup gateway or dst in the routing table to get ifa
*/
if (info->rti_info[RTAX_IFA] != NULL)
sa = info->rti_info[RTAX_IFA];
else if ((info->rti_flags & RTF_GATEWAY) != 0 &&
gateway->sa_family == dst->sa_family)
sa = gateway;
else
sa = dst;
if (info->rti_ifp != NULL) {
info->rti_ifa = ifaof_ifpforaddr(sa, info->rti_ifp);
/* Case 4 */
if (info->rti_ifa == NULL && gateway != NULL)
info->rti_ifa = ifaof_ifpforaddr(gateway, info->rti_ifp);
} else if (dst != NULL && gateway != NULL)
info->rti_ifa = ifa_ifwithroute(flags, dst, gateway,
fibnum);
else if (sa != NULL)
info->rti_ifa = ifa_ifwithroute(flags, sa, sa,
fibnum);
}
if (needref && info->rti_ifa != NULL) {
if (info->rti_ifp == NULL)
info->rti_ifp = info->rti_ifa->ifa_ifp;
ifa_ref(info->rti_ifa);
} else
error = ENETUNREACH;
NET_EPOCH_EXIT(et);
return (error);
}
void
rt_updatemtu(struct ifnet *ifp)
{
struct rib_head *rnh;
int mtu;
int i, j;
/*
* Try to update rt_mtu for all routes using this interface
* Unfortunately the only way to do this is to traverse all
* routing tables in all fibs/domains.
*/
for (i = 1; i <= AF_MAX; i++) {
mtu = if_getmtu_family(ifp, i);
for (j = 0; j < rt_numfibs; j++) {
rnh = rt_tables_get_rnh(j, i);
if (rnh == NULL)
continue;
nhops_update_ifmtu(rnh, ifp, mtu);
}
}
}
#if 0
int p_sockaddr(char *buf, int buflen, struct sockaddr *s);
int rt_print(char *buf, int buflen, struct rtentry *rt);
int
p_sockaddr(char *buf, int buflen, struct sockaddr *s)
{
void *paddr = NULL;
switch (s->sa_family) {
case AF_INET:
paddr = &((struct sockaddr_in *)s)->sin_addr;
break;
case AF_INET6:
paddr = &((struct sockaddr_in6 *)s)->sin6_addr;
break;
}
if (paddr == NULL)
return (0);
if (inet_ntop(s->sa_family, paddr, buf, buflen) == NULL)
return (0);
return (strlen(buf));
}
int
rt_print(char *buf, int buflen, struct rtentry *rt)
{
struct sockaddr *addr, *mask;
int i = 0;
addr = rt_key(rt);
mask = rt_mask(rt);
i = p_sockaddr(buf, buflen, addr);
if (!(rt->rt_flags & RTF_HOST)) {
buf[i++] = '/';
i += p_sockaddr(buf + i, buflen - i, mask);
}
if (rt->rt_flags & RTF_GATEWAY) {
buf[i++] = '>';
i += p_sockaddr(buf + i, buflen - i, &rt->rt_nhop->gw_sa);
}
return (i);
}
#endif
void
rt_maskedcopy(struct sockaddr *src, struct sockaddr *dst, struct sockaddr *netmask)
{
u_char *cp1 = (u_char *)src;
u_char *cp2 = (u_char *)dst;
u_char *cp3 = (u_char *)netmask;
u_char *cplim = cp2 + *cp3;
u_char *cplim2 = cp2 + *cp1;
*cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
cp3 += 2;
if (cplim > cplim2)
cplim = cplim2;
while (cp2 < cplim)
*cp2++ = *cp1++ & *cp3++;
if (cp2 < cplim2)
bzero((caddr_t)cp2, (unsigned)(cplim2 - cp2));
}
/*
* Announce interface address arrival/withdraw
* Returns 0 on success.
*/
int
rt_addrmsg(int cmd, struct ifaddr *ifa, int fibnum)
{
KASSERT(cmd == RTM_ADD || cmd == RTM_DELETE,
("unexpected cmd %d", cmd));
KASSERT((fibnum >= 0 && fibnum < rt_numfibs),
("%s: fib out of range 0 <=%d<%d", __func__, fibnum, rt_numfibs));
EVENTHANDLER_DIRECT_INVOKE(rt_addrmsg, ifa, cmd);
if (V_rt_add_addr_allfibs)
fibnum = RT_ALL_FIBS;
return (rtsock_addrmsg(cmd, ifa, fibnum));
}
/*
* Announce kernel-originated route addition/removal to rtsock based on @rt data.
* cmd: RTM_ cmd
* @rt: valid rtentry
* @nh: nhop object to announce
* @fibnum: fib id or RT_ALL_FIBS
*
* Returns 0 on success.
*/
int
rt_routemsg(int cmd, struct rtentry *rt, struct nhop_object *nh,
int fibnum)
{
KASSERT(cmd == RTM_ADD || cmd == RTM_DELETE,
("unexpected cmd %d", cmd));
KASSERT(fibnum == RT_ALL_FIBS || (fibnum >= 0 && fibnum < rt_numfibs),
("%s: fib out of range 0 <=%d<%d", __func__, fibnum, rt_numfibs));
KASSERT(rt_key(rt) != NULL, (":%s: rt_key must be supplied", __func__));
return (rtsock_routemsg(cmd, rt, nh, fibnum));
}
/*
* Announce kernel-originated route addition/removal to rtsock based on @rt data.
* cmd: RTM_ cmd
* @info: addrinfo structure with valid data.
* @fibnum: fib id or RT_ALL_FIBS
*
* Returns 0 on success.
*/
int
rt_routemsg_info(int cmd, struct rt_addrinfo *info, int fibnum)
{
KASSERT(cmd == RTM_ADD || cmd == RTM_DELETE || cmd == RTM_CHANGE,
("unexpected cmd %d", cmd));
KASSERT(fibnum == RT_ALL_FIBS || (fibnum >= 0 && fibnum < rt_numfibs),
("%s: fib out of range 0 <=%d<%d", __func__, fibnum, rt_numfibs));
KASSERT(info->rti_info[RTAX_DST] != NULL, (":%s: RTAX_DST must be supplied", __func__));
return (rtsock_routemsg_info(cmd, info, fibnum));
}