freebsd-dev/sys/net/route.c
Alexander V. Chernikov da187ddb3d * Add rib_<add|del|change>_route() functions to manipulate the routing table.
The main driver for the change is the need to improve notification mechanism.
Currently callers guess the operation data based on the rtentry structure
 returned in case of successful operation result. There are two problems with
 this appoach. First is that it doesn't provide enough information for the
 upcoming multipath changes, where rtentry refers to a new nexthop group,
 and there is no way of guessing which paths were added during the change.
 Second is that some rtentry fields can change during notification and
 protecting from it by requiring customers to unlock rtentry is not desired.

Additionally, as the consumers such as rtsock do know which operation they
 request in advance, making explicit add/change/del versions of the functions
 makes sense, especially given the functions don't share a lot of code.

With that in mind, introduce rib_cmd_info notification structure and
 rib_<add|del|change>_route() functions, with mandatory rib_cmd_info pointer.
 It will be used in upcoming generalized notifications.

* Move definitions of the new functions and some other functions/structures
 used for the routing table manipulation to a separate header file,
 net/route/route_ctl.h. net/route.h is a frequently used file included in
 ~140 places in kernel, and 90% of the users don't need these definitions.

Reviewed by:		ae
Differential Revision:	https://reviews.freebsd.org/D25067
2020-06-01 20:49:42 +00:00

1537 lines
37 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_mpath.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/route/shared.h>
#include <net/vnet.h>
#ifdef RADIX_MPATH
#include <net/radix_mpath.h>
#endif
#include <netinet/in.h>
#include <netinet/ip_mroute.h>
#include <vm/uma.h>
#define RT_MAXFIBS UINT16_MAX
/* Kernel config default option. */
#ifdef ROUTETABLES
#if ROUTETABLES <= 0
#error "ROUTETABLES defined too low"
#endif
#if ROUTETABLES > RT_MAXFIBS
#error "ROUTETABLES defined too big"
#endif
#define RT_NUMFIBS ROUTETABLES
#endif /* ROUTETABLES */
/* Initialize to default if not otherwise set. */
#ifndef RT_NUMFIBS
#define RT_NUMFIBS 1
#endif
/* This is read-only.. */
u_int rt_numfibs = RT_NUMFIBS;
SYSCTL_UINT(_net, OID_AUTO, fibs, CTLFLAG_RDTUN, &rt_numfibs, 0, "");
/*
* By default add routes to all fibs for new interfaces.
* Once this is set to 0 then only allocate routes on interface
* changes for the FIB of the caller when adding a new set of addresses
* to an interface. XXX this is a shotgun aproach to a problem that needs
* a more fine grained solution.. that will come.
* XXX also has the problems getting the FIB from curthread which will not
* always work given the fib can be overridden and prefixes can be added
* from the network stack context.
*/
VNET_DEFINE(u_int, rt_add_addr_allfibs) = 1;
SYSCTL_UINT(_net, OID_AUTO, add_addr_allfibs, CTLFLAG_RWTUN | CTLFLAG_VNET,
&VNET_NAME(rt_add_addr_allfibs), 0, "");
VNET_PCPUSTAT_DEFINE(struct rtstat, rtstat);
VNET_PCPUSTAT_SYSINIT(rtstat);
#ifdef VIMAGE
VNET_PCPUSTAT_SYSUNINIT(rtstat);
#endif
VNET_DEFINE(struct rib_head *, rt_tables);
#define V_rt_tables VNET(rt_tables)
VNET_DEFINE(uma_zone_t, rtzone); /* Routing table UMA zone. */
#define V_rtzone VNET(rtzone)
EVENTHANDLER_LIST_DEFINE(rt_addrmsg);
static int rt_ifdelroute(const struct rtentry *rt, const struct nhop_object *,
void *arg);
static void destroy_rtentry_epoch(epoch_context_t ctx);
static int rt_exportinfo(struct rtentry *rt, struct rt_addrinfo *info,
int flags);
/*
* handler for net.my_fibnum
*/
static int
sysctl_my_fibnum(SYSCTL_HANDLER_ARGS)
{
int fibnum;
int error;
fibnum = curthread->td_proc->p_fibnum;
error = sysctl_handle_int(oidp, &fibnum, 0, req);
return (error);
}
SYSCTL_PROC(_net, OID_AUTO, my_fibnum,
CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
&sysctl_my_fibnum, "I",
"default FIB of caller");
static __inline struct rib_head **
rt_tables_get_rnh_ptr(int table, int fam)
{
struct rib_head **rnh;
KASSERT(table >= 0 && table < rt_numfibs,
("%s: table out of bounds (0 <= %d < %d)", __func__, table,
rt_numfibs));
KASSERT(fam >= 0 && fam < (AF_MAX + 1),
("%s: fam out of bounds (0 <= %d < %d)", __func__, fam, AF_MAX+1));
/* rnh is [fib=0][af=0]. */
rnh = (struct rib_head **)V_rt_tables;
/* Get the offset to the requested table and fam. */
rnh += table * (AF_MAX+1) + fam;
return (rnh);
}
struct rib_head *
rt_tables_get_rnh(int table, int fam)
{
return (*rt_tables_get_rnh_ptr(table, fam));
}
u_int
rt_tables_get_gen(int table, int fam)
{
struct rib_head *rnh;
rnh = *rt_tables_get_rnh_ptr(table, fam);
KASSERT(rnh != NULL, ("%s: NULL rib_head pointer table %d fam %d",
__func__, table, fam));
return (rnh->rnh_gen);
}
/*
* route initialization must occur before ip6_init2(), which happenas at
* SI_ORDER_MIDDLE.
*/
static void
route_init(void)
{
/* whack the tunable ints into line. */
if (rt_numfibs > RT_MAXFIBS)
rt_numfibs = RT_MAXFIBS;
if (rt_numfibs == 0)
rt_numfibs = 1;
nhops_init();
}
SYSINIT(route_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, NULL);
static int
rtentry_zinit(void *mem, int size, int how)
{
struct rtentry *rt = mem;
RT_LOCK_INIT(rt);
return (0);
}
static void
rtentry_zfini(void *mem, int size)
{
struct rtentry *rt = mem;
RT_LOCK_DESTROY(rt);
}
static int
rtentry_ctor(void *mem, int size, void *arg, int how)
{
struct rtentry *rt = mem;
bzero(rt, offsetof(struct rtentry, rt_endzero));
rt->rt_chain = NULL;
return (0);
}
static void
rtentry_dtor(void *mem, int size, void *arg)
{
struct rtentry *rt = mem;
RT_UNLOCK_COND(rt);
}
static void
vnet_route_init(const void *unused __unused)
{
struct domain *dom;
struct rib_head **rnh;
int table;
int fam;
V_rt_tables = malloc(rt_numfibs * (AF_MAX+1) *
sizeof(struct rib_head *), M_RTABLE, M_WAITOK|M_ZERO);
V_rtzone = uma_zcreate("rtentry", sizeof(struct rtentry),
rtentry_ctor, rtentry_dtor,
rtentry_zinit, rtentry_zfini, UMA_ALIGN_PTR, 0);
for (dom = domains; dom; dom = dom->dom_next) {
if (dom->dom_rtattach == NULL)
continue;
for (table = 0; table < rt_numfibs; table++) {
fam = dom->dom_family;
if (table != 0 && fam != AF_INET6 && fam != AF_INET)
break;
rnh = rt_tables_get_rnh_ptr(table, fam);
if (rnh == NULL)
panic("%s: rnh NULL", __func__);
dom->dom_rtattach((void **)rnh, 0, table);
}
}
}
VNET_SYSINIT(vnet_route_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
vnet_route_init, 0);
#ifdef VIMAGE
static void
vnet_route_uninit(const void *unused __unused)
{
int table;
int fam;
struct domain *dom;
struct rib_head **rnh;
for (dom = domains; dom; dom = dom->dom_next) {
if (dom->dom_rtdetach == NULL)
continue;
for (table = 0; table < rt_numfibs; table++) {
fam = dom->dom_family;
if (table != 0 && fam != AF_INET6 && fam != AF_INET)
break;
rnh = rt_tables_get_rnh_ptr(table, fam);
if (rnh == NULL)
panic("%s: rnh NULL", __func__);
dom->dom_rtdetach((void **)rnh, 0);
}
}
/*
* dom_rtdetach calls rt_table_destroy(), which
* schedules deletion for all rtentries, nexthops and control
* structures. Wait for the destruction callbacks to fire.
* Note that this should result in freeing all rtentries, but
* nexthops deletions will be scheduled for the next epoch run
* and will be completed after vnet teardown.
*/
epoch_drain_callbacks(net_epoch_preempt);
free(V_rt_tables, M_RTABLE);
uma_zdestroy(V_rtzone);
}
VNET_SYSUNINIT(vnet_route_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST,
vnet_route_uninit, 0);
#endif
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 */
CK_STAILQ_INIT(&rh->rnh_subscribers);
/* 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)
{
tmproutes_destroy(rh);
rn_walktree(&rh->rmhead.head, rt_freeentry, &rh->rmhead.head);
nhops_destroy_rib(rh);
/* Assume table is already empty */
RIB_LOCK_DESTROY(rh);
free(rh, M_RTABLE);
}
#ifndef _SYS_SYSPROTO_H_
struct setfib_args {
int fibnum;
};
#endif
int
sys_setfib(struct thread *td, struct setfib_args *uap)
{
if (uap->fibnum < 0 || uap->fibnum >= rt_numfibs)
return EINVAL;
td->td_proc->p_fibnum = uap->fibnum;
return (0);
}
/*
* Remove a reference count from an rtentry.
* If the count gets low enough, take it out of the routing table
*/
void
rtfree(struct rtentry *rt)
{
KASSERT(rt != NULL,("%s: NULL rt", __func__));
RT_LOCK_ASSERT(rt);
RT_UNLOCK(rt);
epoch_call(net_epoch_preempt, destroy_rtentry_epoch,
&rt->rt_epoch_ctx);
}
static void
destroy_rtentry(struct rtentry *rt)
{
/*
* At this moment rnh, nh_control may be already freed.
* nhop interface may have been migrated to a different vnet.
* Use vnet stored in the nexthop to delete the entry.
*/
CURVNET_SET(nhop_get_vnet(rt->rt_nhop));
/* Unreference nexthop */
nhop_free(rt->rt_nhop);
uma_zfree(V_rtzone, rt);
CURVNET_RESTORE();
}
/*
* Epoch callback indicating rtentry is safe to destroy
*/
static void
destroy_rtentry_epoch(epoch_context_t ctx)
{
struct rtentry *rt;
rt = __containerof(ctx, struct rtentry, rt_epoch_ctx);
destroy_rtentry(rt);
}
/*
* 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 rtentry *rt;
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));
/* 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 | RTF_HOST | RTF_DYNAMIC;
/* 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 = rtrequest1_fib(RTM_ADD, &info, &rt, fibnum);
ifa_free(ifa);
if (error != 0) {
/* TODO: add per-fib redirect stats. */
return (error);
}
RT_LOCK(rt);
flags = rt->rt_flags;
RT_UNLOCK(rt);
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, 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);
}
/*
* Do appropriate manipulations of a routing tree given
* all the bits of info needed
*/
int
rtrequest_fib(int req,
struct sockaddr *dst,
struct sockaddr *gateway,
struct sockaddr *netmask,
int flags,
struct rtentry **ret_nrt,
u_int fibnum)
{
struct rt_addrinfo info;
if (dst->sa_len == 0)
return(EINVAL);
bzero((caddr_t)&info, sizeof(info));
info.rti_flags = flags;
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_info[RTAX_NETMASK] = netmask;
return rtrequest1_fib(req, &info, ret_nrt, fibnum);
}
/*
* 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.
*/
int
rt_exportinfo(struct rtentry *rt, struct rt_addrinfo *info, int flags)
{
struct rt_metrics *rmx;
struct sockaddr *src, *dst;
struct nhop_object *nh;
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 = &rt->rt_nhop->gw_sa;
dst = info->rti_info[RTAX_GATEWAY];
if ((rt->rt_flags & 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 (rt->rt_flags & RTF_GATEWAY) {
info->rti_info[RTAX_GATEWAY] = &rt->rt_nhop->gw_sa;
info->rti_addrs |= RTA_GATEWAY;
}
}
nh = rt->rt_nhop;
rmx = info->rti_rmx;
if (rmx != NULL) {
info->rti_mflags |= RTV_MTU;
rmx->rmx_mtu = nh->nh_mtu;
}
info->rti_flags = rt->rt_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;
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);
/* Ensure route & ifp is UP */
if (RT_LINK_IS_UP(rt->rt_nhop->nh_ifp)) {
flags = (flags & NHR_REF) | NHR_COPY;
error = rt_exportinfo(rt, 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);
}
/*
* Iterates over all existing fibs in system calling
* @setwa_f function prior to traversing each fib.
* Calls @wa_f function for each element in current fib.
* If af is not AF_UNSPEC, iterates over fibs in particular
* address family.
*/
void
rt_foreach_fib_walk(int af, rt_setwarg_t *setwa_f, rt_walktree_f_t *wa_f,
void *arg)
{
struct rib_head *rnh;
uint32_t fibnum;
int i;
for (fibnum = 0; fibnum < rt_numfibs; fibnum++) {
/* Do we want some specific family? */
if (af != AF_UNSPEC) {
rnh = rt_tables_get_rnh(fibnum, af);
if (rnh == NULL)
continue;
if (setwa_f != NULL)
setwa_f(rnh, fibnum, af, arg);
RIB_WLOCK(rnh);
rnh->rnh_walktree(&rnh->head, (walktree_f_t *)wa_f,arg);
RIB_WUNLOCK(rnh);
continue;
}
for (i = 1; i <= AF_MAX; i++) {
rnh = rt_tables_get_rnh(fibnum, i);
if (rnh == NULL)
continue;
if (setwa_f != NULL)
setwa_f(rnh, fibnum, i, arg);
RIB_WLOCK(rnh);
rnh->rnh_walktree(&rnh->head, (walktree_f_t *)wa_f,arg);
RIB_WUNLOCK(rnh);
}
}
}
/*
* Iterates over all existing fibs in system and deletes each element
* for which @filter_f function returns non-zero value.
* If @family is not AF_UNSPEC, iterates over fibs in particular
* address family.
*/
void
rt_foreach_fib_walk_del(int family, rt_filter_f_t *filter_f, void *arg)
{
u_int fibnum;
int i, start, end;
for (fibnum = 0; fibnum < rt_numfibs; fibnum++) {
/* Do we want some specific family? */
if (family != AF_UNSPEC) {
start = family;
end = family;
} else {
start = 1;
end = AF_MAX;
}
for (i = start; i <= end; i++) {
if (rt_tables_get_rnh(fibnum, i) == NULL)
continue;
rib_walk_del(fibnum, i, filter_f, arg, 0);
}
}
}
/*
* 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->rt_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));
rt_foreach_fib_walk_del(af, rt_ifdelroute, ifp);
}
void
rt_flushifroutes(struct ifnet *ifp)
{
rt_foreach_fib_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
#ifdef RADIX_MPATH
/*
* Deletes key for single-path routes, unlinks rtentry with
* gateway specified in @info from multi-path routes.
*
* Returnes unlinked entry. In case of failure, returns NULL
* and sets @perror to ESRCH.
*/
struct radix_node *
rt_mpath_unlink(struct rib_head *rnh, struct rt_addrinfo *info,
struct rtentry *rto, int *perror)
{
/*
* if we got multipath routes, we require users to specify
* a matching RTAX_GATEWAY.
*/
struct rtentry *rt; // *rto = NULL;
struct radix_node *rn;
struct sockaddr *gw;
gw = info->rti_info[RTAX_GATEWAY];
rt = rt_mpath_matchgate(rto, gw);
if (rt == NULL) {
*perror = ESRCH;
return (NULL);
}
/*
* this is the first entry in the chain
*/
if (rto == rt) {
rn = rn_mpath_next((struct radix_node *)rt);
/*
* there is another entry, now it's active
*/
if (rn) {
rto = RNTORT(rn);
RT_LOCK(rto);
rto->rt_flags |= RTF_UP;
RT_UNLOCK(rto);
} else if (rt->rt_flags & RTF_GATEWAY) {
/*
* For gateway routes, we need to
* make sure that we we are deleting
* the correct gateway.
* rt_mpath_matchgate() does not
* check the case when there is only
* one route in the chain.
*/
if (gw &&
(rt->rt_nhop->gw_sa.sa_len != gw->sa_len ||
memcmp(&rt->rt_nhop->gw_sa, gw, gw->sa_len))) {
*perror = ESRCH;
return (NULL);
}
}
/*
* use the normal delete code to remove
* the first entry
*/
rn = rnh->rnh_deladdr(info->rti_info[RTAX_DST],
info->rti_info[RTAX_NETMASK],
&rnh->head);
*perror = 0;
return (rn);
}
/*
* if the entry is 2nd and on up
*/
if (rt_mpath_deldup(rto, rt) == 0)
panic ("rtrequest1: rt_mpath_deldup");
*perror = 0;
rn = (struct radix_node *)rt;
return (rn);
}
#endif
int
rtrequest1_fib(int req, struct rt_addrinfo *info, struct rtentry **ret_nrt,
u_int fibnum)
{
const struct sockaddr *dst;
struct rib_head *rnh;
struct rib_cmd_info rc;
int error;
KASSERT((fibnum < rt_numfibs), ("rtrequest1_fib: bad fibnum"));
KASSERT((info->rti_flags & RTF_RNH_LOCKED) == 0, ("rtrequest1_fib: locked"));
NET_EPOCH_ASSERT();
dst = info->rti_info[RTAX_DST];
switch (dst->sa_family) {
case AF_INET6:
case AF_INET:
/* We support multiple FIBs. */
break;
default:
fibnum = RT_DEFAULT_FIB;
break;
}
/*
* Find the correct routing tree to use for this Address Family
*/
rnh = rt_tables_get_rnh(fibnum, dst->sa_family);
if (rnh == NULL)
return (EAFNOSUPPORT);
/*
* If we are adding a host route then we don't want to put
* a netmask in the tree, nor do we want to clone it.
*/
if (info->rti_flags & RTF_HOST)
info->rti_info[RTAX_NETMASK] = NULL;
bzero(&rc, sizeof(struct rib_cmd_info));
error = 0;
switch (req) {
case RTM_DELETE:
error = del_route(rnh, info, &rc);
break;
case RTM_RESOLVE:
/*
* resolve was only used for route cloning
* here for compat
*/
break;
case RTM_ADD:
error = add_route(rnh, info, &rc);
break;
case RTM_CHANGE:
error = change_route(rnh, info, &rc);
break;
default:
error = EOPNOTSUPP;
}
if (ret_nrt != NULL)
*ret_nrt = rc.rc_rt;
return (error);
}
void
rt_setmetrics(const struct rt_addrinfo *info, struct rtentry *rt)
{
if (info->rti_mflags & RTV_WEIGHT)
rt->rt_weight = info->rti_rmx->rmx_weight;
/* Kernel -> userland timebase conversion. */
if (info->rti_mflags & RTV_EXPIRE)
rt->rt_expire = info->rti_rmx->rmx_expire ?
info->rti_rmx->rmx_expire - time_second + time_uptime : 0;
}
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));
}
/*
* Set up a routing table entry, normally
* for an interface.
*/
#define _SOCKADDR_TMPSIZE 128 /* Not too big.. kernel stack size is limited */
static inline int
rtinit1(struct ifaddr *ifa, int cmd, int flags, int fibnum)
{
RIB_RLOCK_TRACKER;
struct epoch_tracker et;
struct sockaddr *dst;
struct sockaddr *netmask;
struct rtentry *rt = NULL;
struct rt_addrinfo info;
int error = 0;
int startfib, endfib;
char tempbuf[_SOCKADDR_TMPSIZE];
int didwork = 0;
int a_failure = 0;
struct sockaddr_dl_short *sdl = NULL;
struct rib_head *rnh;
if (flags & RTF_HOST) {
dst = ifa->ifa_dstaddr;
netmask = NULL;
} else {
dst = ifa->ifa_addr;
netmask = ifa->ifa_netmask;
}
if (dst->sa_len == 0)
return(EINVAL);
switch (dst->sa_family) {
case AF_INET6:
case AF_INET:
/* We support multiple FIBs. */
break;
default:
fibnum = RT_DEFAULT_FIB;
break;
}
if (fibnum == RT_ALL_FIBS) {
if (V_rt_add_addr_allfibs == 0 && cmd == (int)RTM_ADD)
startfib = endfib = ifa->ifa_ifp->if_fib;
else {
startfib = 0;
endfib = rt_numfibs - 1;
}
} else {
KASSERT((fibnum < rt_numfibs), ("rtinit1: bad fibnum"));
startfib = fibnum;
endfib = fibnum;
}
/*
* If it's a delete, check that if it exists,
* it's on the correct interface or we might scrub
* a route to another ifa which would
* be confusing at best and possibly worse.
*/
if (cmd == RTM_DELETE) {
/*
* It's a delete, so it should already exist..
* If it's a net, mask off the host bits
* (Assuming we have a mask)
* XXX this is kinda inet specific..
*/
if (netmask != NULL) {
rt_maskedcopy(dst, (struct sockaddr *)tempbuf, netmask);
dst = (struct sockaddr *)tempbuf;
}
} else if (cmd == RTM_ADD) {
sdl = (struct sockaddr_dl_short *)tempbuf;
bzero(sdl, sizeof(struct sockaddr_dl_short));
sdl->sdl_family = AF_LINK;
sdl->sdl_len = sizeof(struct sockaddr_dl_short);
sdl->sdl_type = ifa->ifa_ifp->if_type;
sdl->sdl_index = ifa->ifa_ifp->if_index;
}
/*
* Now go through all the requested tables (fibs) and do the
* requested action. Realistically, this will either be fib 0
* for protocols that don't do multiple tables or all the
* tables for those that do.
*/
for ( fibnum = startfib; fibnum <= endfib; fibnum++) {
if (cmd == RTM_DELETE) {
struct radix_node *rn;
/*
* Look up an rtentry that is in the routing tree and
* contains the correct info.
*/
rnh = rt_tables_get_rnh(fibnum, dst->sa_family);
if (rnh == NULL)
/* this table doesn't exist but others might */
continue;
RIB_RLOCK(rnh);
rn = rnh->rnh_lookup(dst, netmask, &rnh->head);
#ifdef RADIX_MPATH
if (rt_mpath_capable(rnh)) {
if (rn == NULL)
error = ESRCH;
else {
rt = RNTORT(rn);
/*
* for interface route the gateway
* gateway is sockaddr_dl, so
* rt_mpath_matchgate must use the
* interface address
*/
rt = rt_mpath_matchgate(rt,
ifa->ifa_addr);
if (rt == NULL)
error = ESRCH;
}
}
#endif
error = (rn == NULL ||
(rn->rn_flags & RNF_ROOT) ||
RNTORT(rn)->rt_nhop->nh_ifa != ifa);
RIB_RUNLOCK(rnh);
if (error) {
/* this is only an error if bad on ALL tables */
continue;
}
}
/*
* Do the actual request
*/
bzero((caddr_t)&info, sizeof(info));
info.rti_ifa = ifa;
info.rti_flags = flags |
(ifa->ifa_flags & ~IFA_RTSELF) | RTF_PINNED;
info.rti_info[RTAX_DST] = dst;
/*
* doing this for compatibility reasons
*/
if (cmd == RTM_ADD)
info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)sdl;
else
info.rti_info[RTAX_GATEWAY] = ifa->ifa_addr;
info.rti_info[RTAX_NETMASK] = netmask;
NET_EPOCH_ENTER(et);
error = rtrequest1_fib(cmd, &info, &rt, fibnum);
if (error == 0 && rt != NULL) {
/*
* notify any listening routing agents of the change
*/
/* TODO: interface routes/aliases */
rt_newaddrmsg_fib(cmd, ifa, rt, fibnum);
didwork = 1;
}
NET_EPOCH_EXIT(et);
if (error)
a_failure = error;
}
if (cmd == RTM_DELETE) {
if (didwork) {
error = 0;
} else {
/* we only give an error if it wasn't in any table */
error = ((flags & RTF_HOST) ?
EHOSTUNREACH : ENETUNREACH);
}
} else {
if (a_failure) {
/* return an error if any of them failed */
error = a_failure;
}
}
return (error);
}
/*
* Set up a routing table entry, normally
* for an interface.
*/
int
rtinit(struct ifaddr *ifa, int cmd, int flags)
{
struct sockaddr *dst;
int fib = RT_DEFAULT_FIB;
if (flags & RTF_HOST) {
dst = ifa->ifa_dstaddr;
} else {
dst = ifa->ifa_addr;
}
switch (dst->sa_family) {
case AF_INET6:
case AF_INET:
/* We do support multiple FIBs. */
fib = RT_ALL_FIBS;
break;
}
return (rtinit1(ifa, cmd, flags, fib));
}
/*
* 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 == RT_ALL_FIBS || (fibnum >= 0 && fibnum < rt_numfibs),
("%s: fib out of range 0 <=%d<%d", __func__, fibnum, rt_numfibs));
EVENTHANDLER_DIRECT_INVOKE(rt_addrmsg, ifa, cmd);
return (rtsock_addrmsg(cmd, ifa, fibnum));
}
/*
* Announce kernel-originated route addition/removal to rtsock based on @rt data.
* cmd: RTM_ cmd
* @rt: valid rtentry
* @ifp: target route interface
* @fibnum: fib id or RT_ALL_FIBS
*
* Returns 0 on success.
*/
int
rt_routemsg(int cmd, struct rtentry *rt, struct ifnet *ifp, int rti_addrs,
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, ifp, 0, 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));
}
/*
* This is called to generate messages from the routing socket
* indicating a network interface has had addresses associated with it.
*/
void
rt_newaddrmsg_fib(int cmd, struct ifaddr *ifa, struct rtentry *rt, int fibnum)
{
KASSERT(cmd == RTM_ADD || cmd == RTM_DELETE,
("unexpected cmd %u", cmd));
KASSERT(fibnum == RT_ALL_FIBS || (fibnum >= 0 && fibnum < rt_numfibs),
("%s: fib out of range 0 <=%d<%d", __func__, fibnum, rt_numfibs));
if (cmd == RTM_ADD) {
rt_addrmsg(cmd, ifa, fibnum);
if (rt != NULL)
rt_routemsg(cmd, rt, ifa->ifa_ifp, 0, fibnum);
} else {
if (rt != NULL)
rt_routemsg(cmd, rt, ifa->ifa_ifp, 0, fibnum);
rt_addrmsg(cmd, ifa, fibnum);
}
}