Index: head/sys/net/route/route_ctl.c =================================================================== --- head/sys/net/route/route_ctl.c (revision 365553) +++ head/sys/net/route/route_ctl.c (revision 365554) @@ -1,1185 +1,1187 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2020 Alexander V. Chernikov * * 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 THE 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 THE 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 __FBSDID("$FreeBSD$"); #include "opt_inet.h" #include "opt_inet6.h" #include "opt_mpath.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef RADIX_MPATH #include #endif #include /* * This file contains control plane routing tables functions. * * All functions assumes they are called in net epoch. */ struct rib_subscription { CK_STAILQ_ENTRY(rib_subscription) next; rib_subscription_cb_t *func; void *arg; enum rib_subscription_type type; struct epoch_context epoch_ctx; }; static int add_route(struct rib_head *rnh, struct rt_addrinfo *info, struct rib_cmd_info *rc); static int add_route_nhop(struct rib_head *rnh, struct rtentry *rt, struct rt_addrinfo *info, struct route_nhop_data *rnd, struct rib_cmd_info *rc); static int del_route(struct rib_head *rnh, struct rt_addrinfo *info, struct rib_cmd_info *rc); static int change_route(struct rib_head *rnh, struct rt_addrinfo *info, struct route_nhop_data *nhd_orig, struct rib_cmd_info *rc); static int change_route_nhop(struct rib_head *rnh, struct rtentry *rt, struct rt_addrinfo *info, struct route_nhop_data *rnd, struct rib_cmd_info *rc); static int rt_unlinkrte(struct rib_head *rnh, struct rt_addrinfo *info, struct rib_cmd_info *rc); static void rib_notify(struct rib_head *rnh, enum rib_subscription_type type, struct rib_cmd_info *rc); static void destroy_subscription_epoch(epoch_context_t ctx); /* Routing table UMA zone */ VNET_DEFINE_STATIC(uma_zone_t, rtzone); #define V_rtzone VNET(rtzone) void vnet_rtzone_init() { V_rtzone = uma_zcreate("rtentry", sizeof(struct rtentry), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); } #ifdef VIMAGE void vnet_rtzone_destroy() { uma_zdestroy(V_rtzone); } #endif 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); } /* * Schedule rtentry deletion */ static void rtfree(struct rtentry *rt) { KASSERT(rt != NULL, ("%s: NULL rt", __func__)); epoch_call(net_epoch_preempt, destroy_rtentry_epoch, &rt->rt_epoch_ctx); } static struct rib_head * get_rnh(uint32_t fibnum, const struct rt_addrinfo *info) { struct rib_head *rnh; struct sockaddr *dst; KASSERT((fibnum < rt_numfibs), ("rib_add_route: bad fibnum")); dst = info->rti_info[RTAX_DST]; rnh = rt_tables_get_rnh(fibnum, dst->sa_family); return (rnh); } /* * Check if specified @gw matches gw data in the nexthop @nh. * * Returns true if matches, false otherwise. */ static bool match_nhop_gw(const struct nhop_object *nh, const struct sockaddr *gw) { if (nh->gw_sa.sa_family != gw->sa_family) return (false); switch (gw->sa_family) { case AF_INET: return (nh->gw4_sa.sin_addr.s_addr == ((const struct sockaddr_in *)gw)->sin_addr.s_addr); case AF_INET6: { const struct sockaddr_in6 *gw6; gw6 = (const struct sockaddr_in6 *)gw; /* * Currently (2020-09) IPv6 gws in kernel have their * scope embedded. Once this becomes false, this code * has to be revisited. */ if (IN6_ARE_ADDR_EQUAL(&nh->gw6_sa.sin6_addr, &gw6->sin6_addr)) return (true); return (false); } case AF_LINK: { const struct sockaddr_dl *sdl; sdl = (const struct sockaddr_dl *)gw; return (nh->gwl_sa.sdl_index == sdl->sdl_index); } default: return (memcmp(&nh->gw_sa, gw, nh->gw_sa.sa_len) == 0); } /* NOTREACHED */ return (false); } /* * Checks if data in @info matches nexhop @nh. * * Returns 0 on success, * ESRCH if not matched, * ENOENT if filter function returned false */ int check_info_match_nhop(const struct rt_addrinfo *info, const struct rtentry *rt, const struct nhop_object *nh) { const struct sockaddr *gw = info->rti_info[RTAX_GATEWAY]; if (info->rti_filter != NULL) { if (info->rti_filter(rt, nh, info->rti_filterdata) == 0) return (ENOENT); else return (0); } if ((gw != NULL) && !match_nhop_gw(nh, gw)) return (ESRCH); return (0); } /* * Checks if nexhop @nh can be rewritten by data in @info because * of higher "priority". Currently the only case for such scenario * is kernel installing interface routes, marked by RTF_PINNED flag. * * Returns: * 1 if @info data has higher priority * 0 if priority is the same * -1 if priority is lower */ int can_override_nhop(const struct rt_addrinfo *info, const struct nhop_object *nh) { if (info->rti_flags & RTF_PINNED) { return (NH_IS_PINNED(nh)) ? 0 : 1; } else { return (NH_IS_PINNED(nh)) ? -1 : 0; } } /* * Runs exact prefix match based on @dst and @netmask. * Returns matched @rtentry if found or NULL. * If rtentry was found, saves nexthop / weight value into @rnd. */ static struct rtentry * lookup_prefix_bysa(struct rib_head *rnh, const struct sockaddr *dst, const struct sockaddr *netmask, struct route_nhop_data *rnd) { struct rtentry *rt; RIB_LOCK_ASSERT(rnh); rt = (struct rtentry *)rnh->rnh_lookup(__DECONST(void *, dst), __DECONST(void *, netmask), &rnh->head); if (rt != NULL) { rnd->rnd_nhop = rt->rt_nhop; rnd->rnd_weight = rt->rt_weight; } else { rnd->rnd_nhop = NULL; rnd->rnd_weight = 0; } return (rt); } /* * Runs exact prefix match based on dst/netmask from @info. * Assumes RIB lock is held. * Returns matched @rtentry if found or NULL. * If rtentry was found, saves nexthop / weight value into @rnd. */ struct rtentry * lookup_prefix(struct rib_head *rnh, const struct rt_addrinfo *info, struct route_nhop_data *rnd) { struct rtentry *rt; rt = lookup_prefix_bysa(rnh, info->rti_info[RTAX_DST], info->rti_info[RTAX_NETMASK], rnd); return (rt); } /* * Adds route defined by @info into the kernel table specified by @fibnum and * sa_family in @info->rti_info[RTAX_DST]. * * Returns 0 on success and fills in operation metadata into @rc. */ int rib_add_route(uint32_t fibnum, struct rt_addrinfo *info, struct rib_cmd_info *rc) { struct rib_head *rnh; int error; NET_EPOCH_ASSERT(); rnh = get_rnh(fibnum, info); if (rnh == NULL) return (EAFNOSUPPORT); /* * Check consistency between RTF_HOST flag and netmask * existence. */ if (info->rti_flags & RTF_HOST) info->rti_info[RTAX_NETMASK] = NULL; else if (info->rti_info[RTAX_NETMASK] == NULL) return (EINVAL); bzero(rc, sizeof(struct rib_cmd_info)); rc->rc_cmd = RTM_ADD; error = add_route(rnh, info, rc); if (error == 0) rib_notify(rnh, RIB_NOTIFY_DELAYED, rc); return (error); } /* * Creates rtentry and nexthop based on @info data. * Return 0 and fills in rtentry into @prt on success, * return errno otherwise. */ static int create_rtentry(struct rib_head *rnh, struct rt_addrinfo *info, struct rtentry **prt) { struct sockaddr *dst, *ndst, *gateway, *netmask; struct rtentry *rt; struct nhop_object *nh; struct ifaddr *ifa; int error, flags; dst = info->rti_info[RTAX_DST]; gateway = info->rti_info[RTAX_GATEWAY]; netmask = info->rti_info[RTAX_NETMASK]; flags = info->rti_flags; if ((flags & RTF_GATEWAY) && !gateway) return (EINVAL); if (dst && gateway && (dst->sa_family != gateway->sa_family) && (gateway->sa_family != AF_UNSPEC) && (gateway->sa_family != AF_LINK)) return (EINVAL); if (dst->sa_len > sizeof(((struct rtentry *)NULL)->rt_dstb)) return (EINVAL); if (info->rti_ifa == NULL) { error = rt_getifa_fib(info, rnh->rib_fibnum); if (error) return (error); } else { ifa_ref(info->rti_ifa); } error = nhop_create_from_info(rnh, info, &nh); if (error != 0) { ifa_free(info->rti_ifa); return (error); } rt = uma_zalloc(V_rtzone, M_NOWAIT | M_ZERO); if (rt == NULL) { ifa_free(info->rti_ifa); nhop_free(nh); return (ENOBUFS); } rt->rte_flags = RTF_UP | flags; rt->rt_nhop = nh; /* Fill in dst */ memcpy(&rt->rt_dst, dst, dst->sa_len); rt_key(rt) = &rt->rt_dst; /* * point to the (possibly newly malloc'd) dest address. */ ndst = (struct sockaddr *)rt_key(rt); /* * make sure it contains the value we want (masked if needed). */ if (netmask) { rt_maskedcopy(dst, ndst, netmask); } else bcopy(dst, ndst, dst->sa_len); /* * We use the ifa reference returned by rt_getifa_fib(). * This moved from below so that rnh->rnh_addaddr() can * examine the ifa and ifa->ifa_ifp if it so desires. */ ifa = info->rti_ifa; rt->rt_weight = 1; rt_setmetrics(info, rt); *prt = rt; return (0); } static int add_route(struct rib_head *rnh, struct rt_addrinfo *info, struct rib_cmd_info *rc) { struct nhop_object *nh_orig; struct route_nhop_data rnd; struct nhop_object *nh; struct rtentry *rt, *rt_orig; int error; error = create_rtentry(rnh, info, &rt); if (error != 0) return (error); rnd.rnd_nhop = rt->rt_nhop; rnd.rnd_weight = rt->rt_weight; nh = rt->rt_nhop; RIB_WLOCK(rnh); #ifdef RADIX_MPATH struct sockaddr *netmask; netmask = info->rti_info[RTAX_NETMASK]; /* do not permit exactly the same dst/mask/gw pair */ if (rt_mpath_capable(rnh) && rt_mpath_conflict(rnh, rt, netmask)) { RIB_WUNLOCK(rnh); nhop_free(nh); uma_zfree(V_rtzone, rt); return (EEXIST); } #endif error = add_route_nhop(rnh, rt, info, &rnd, rc); if (error == 0) { RIB_WUNLOCK(rnh); return (0); } /* addition failed. Lookup prefix in the rib to determine the cause */ rt_orig = lookup_prefix(rnh, info, &rnd); if (rt_orig == NULL) { /* No prefix -> rnh_addaddr() failed to allocate memory */ RIB_WUNLOCK(rnh); nhop_free(nh); uma_zfree(V_rtzone, rt); return (ENOMEM); } /* We have existing route in the RIB. */ nh_orig = rnd.rnd_nhop; /* Check if new route has higher preference */ if (can_override_nhop(info, nh_orig) > 0) { /* Update nexthop to the new route */ change_route_nhop(rnh, rt_orig, info, &rnd, rc); RIB_WUNLOCK(rnh); uma_zfree(V_rtzone, rt); nhop_free(nh_orig); return (0); } RIB_WUNLOCK(rnh); /* Unable to add - another route with the same preference exists */ error = EEXIST; nhop_free(nh); uma_zfree(V_rtzone, rt); return (error); } /* * Removes route defined by @info from the kernel table specified by @fibnum and * sa_family in @info->rti_info[RTAX_DST]. * * Returns 0 on success and fills in operation metadata into @rc. */ int rib_del_route(uint32_t fibnum, struct rt_addrinfo *info, struct rib_cmd_info *rc) { struct rib_head *rnh; struct sockaddr *dst_orig, *netmask; struct sockaddr_storage mdst; int error; NET_EPOCH_ASSERT(); rnh = get_rnh(fibnum, info); if (rnh == NULL) return (EAFNOSUPPORT); bzero(rc, sizeof(struct rib_cmd_info)); rc->rc_cmd = RTM_DELETE; dst_orig = info->rti_info[RTAX_DST]; netmask = info->rti_info[RTAX_NETMASK]; if (netmask != NULL) { /* Ensure @dst is always properly masked */ if (dst_orig->sa_len > sizeof(mdst)) return (EINVAL); rt_maskedcopy(dst_orig, (struct sockaddr *)&mdst, netmask); info->rti_info[RTAX_DST] = (struct sockaddr *)&mdst; } error = del_route(rnh, info, rc); info->rti_info[RTAX_DST] = dst_orig; return (error); } /* * Conditionally unlinks rtentry matching data inside @info from @rnh. * Returns 0 on success with operation result stored in @rc. * On error, returns: * ESRCH - if prefix was not found, * EADDRINUSE - if trying to delete higher priority route. * ENOENT - if supplied filter function returned 0 (not matched). */ static int rt_unlinkrte(struct rib_head *rnh, struct rt_addrinfo *info, struct rib_cmd_info *rc) { struct rtentry *rt; struct nhop_object *nh; struct radix_node *rn; struct route_nhop_data rnd; int error; rt = lookup_prefix(rnh, info, &rnd); if (rt == NULL) return (ESRCH); nh = rt->rt_nhop; error = check_info_match_nhop(info, rt, nh); if (error != 0) return (error); if (can_override_nhop(info, nh) < 0) return (EADDRINUSE); /* * Remove the item from the tree and return it. * Complain if it is not there and do no more processing. */ #ifdef RADIX_MPATH info->rti_info[RTAX_GATEWAY] = &nh->gw_sa; - if (rt_mpath_capable(rnh)) - rn = rt_mpath_unlink(rnh, info, rt, perror); - else + if (rt_mpath_capable(rnh)) { + rn = rt_mpath_unlink(rnh, info, rt, &error); + if (error != 0) + return (error); + } else #endif rn = rnh->rnh_deladdr(info->rti_info[RTAX_DST], info->rti_info[RTAX_NETMASK], &rnh->head); if (rn == NULL) return (ESRCH); if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)) panic ("rtrequest delete"); rt = RNTORT(rn); rt->rte_flags &= ~RTF_UP; /* Finalize notification */ rnh->rnh_gen++; rc->rc_cmd = RTM_DELETE; rc->rc_rt = rt; rc->rc_nh_old = rt->rt_nhop; rc->rc_nh_weight = rt->rt_weight; rib_notify(rnh, RIB_NOTIFY_IMMEDIATE, rc); return (0); } static int del_route(struct rib_head *rnh, struct rt_addrinfo *info, struct rib_cmd_info *rc) { int error; RIB_WLOCK(rnh); error = rt_unlinkrte(rnh, info, rc); RIB_WUNLOCK(rnh); if (error != 0) return (error); rib_notify(rnh, RIB_NOTIFY_DELAYED, rc); /* * If the caller wants it, then it can have it, * the entry will be deleted after the end of the current epoch. */ rtfree(rc->rc_rt); return (0); } int rib_change_route(uint32_t fibnum, struct rt_addrinfo *info, struct rib_cmd_info *rc) { RIB_RLOCK_TRACKER; struct route_nhop_data rnd_orig; struct rib_head *rnh; struct rtentry *rt; int error; NET_EPOCH_ASSERT(); rnh = get_rnh(fibnum, info); if (rnh == NULL) return (EAFNOSUPPORT); bzero(rc, sizeof(struct rib_cmd_info)); rc->rc_cmd = RTM_CHANGE; /* Check if updated gateway exists */ if ((info->rti_flags & RTF_GATEWAY) && (info->rti_info[RTAX_GATEWAY] == NULL)) return (EINVAL); /* * route change is done in multiple steps, with dropping and * reacquiring lock. In the situations with multiple processes * changes the same route in can lead to the case when route * is changed between the steps. Address it by retrying the operation * multiple times before failing. */ RIB_RLOCK(rnh); rt = (struct rtentry *)rnh->rnh_lookup(info->rti_info[RTAX_DST], info->rti_info[RTAX_NETMASK], &rnh->head); if (rt == NULL) { RIB_RUNLOCK(rnh); return (ESRCH); } #ifdef RADIX_MPATH /* * If we got multipath routes, * we require users to specify a matching RTAX_GATEWAY. */ if (rt_mpath_capable(rnh)) { rt = rt_mpath_matchgate(rt, info->rti_info[RTAX_GATEWAY]); if (rt == NULL) { RIB_RUNLOCK(rnh); return (ESRCH); } } #endif rnd_orig.rnd_nhop = rt->rt_nhop; rnd_orig.rnd_weight = rt->rt_weight; RIB_RUNLOCK(rnh); for (int i = 0; i < RIB_MAX_RETRIES; i++) { error = change_route(rnh, info, &rnd_orig, rc); if (error != EAGAIN) break; } return (error); } static int change_route(struct rib_head *rnh, struct rt_addrinfo *info, struct route_nhop_data *rnd_orig, struct rib_cmd_info *rc) { int error = 0; int free_ifa = 0; struct nhop_object *nh, *nh_orig; struct route_nhop_data rnd_new; nh = NULL; nh_orig = rnd_orig->rnd_nhop; if (nh_orig == NULL) return (ESRCH); /* * New gateway could require new ifaddr, ifp; * flags may also be different; ifp may be specified * by ll sockaddr when protocol address is ambiguous */ if (((nh_orig->nh_flags & NHF_GATEWAY) && info->rti_info[RTAX_GATEWAY] != NULL) || info->rti_info[RTAX_IFP] != NULL || (info->rti_info[RTAX_IFA] != NULL && !sa_equal(info->rti_info[RTAX_IFA], nh_orig->nh_ifa->ifa_addr))) { error = rt_getifa_fib(info, rnh->rib_fibnum); if (info->rti_ifa != NULL) free_ifa = 1; if (error != 0) { if (free_ifa) { ifa_free(info->rti_ifa); info->rti_ifa = NULL; } return (error); } } error = nhop_create_from_nhop(rnh, nh_orig, info, &nh); if (free_ifa) { ifa_free(info->rti_ifa); info->rti_ifa = NULL; } if (error != 0) return (error); rnd_new.rnd_nhop = nh; if (info->rti_mflags & RTV_WEIGHT) rnd_new.rnd_weight = info->rti_rmx->rmx_weight; else rnd_new.rnd_weight = rnd_orig->rnd_weight; error = change_route_conditional(rnh, NULL, info, rnd_orig, &rnd_new, rc); return (error); } /* * Insert @rt with nhop data from @rnd_new to @rnh. * Returns 0 on success and stores operation results in @rc. */ static int add_route_nhop(struct rib_head *rnh, struct rtentry *rt, struct rt_addrinfo *info, struct route_nhop_data *rnd, struct rib_cmd_info *rc) { struct sockaddr *ndst, *netmask; struct radix_node *rn; int error = 0; RIB_WLOCK_ASSERT(rnh); ndst = (struct sockaddr *)rt_key(rt); netmask = info->rti_info[RTAX_NETMASK]; rt->rt_nhop = rnd->rnd_nhop; rt->rt_weight = rnd->rnd_weight; rn = rnh->rnh_addaddr(ndst, netmask, &rnh->head, rt->rt_nodes); if (rn != NULL) { if (rt->rt_expire > 0) tmproutes_update(rnh, rt); /* Finalize notification */ rnh->rnh_gen++; rc->rc_cmd = RTM_ADD; rc->rc_rt = rt; rc->rc_nh_old = NULL; rc->rc_nh_new = rnd->rnd_nhop; rc->rc_nh_weight = rnd->rnd_weight; rib_notify(rnh, RIB_NOTIFY_IMMEDIATE, rc); } else { /* Existing route or memory allocation failure */ error = EEXIST; } return (error); } /* * Switch @rt nhop/weigh to the ones specified in @rnd. * Conditionally set rt_expire if set in @info. * Returns 0 on success. */ static int change_route_nhop(struct rib_head *rnh, struct rtentry *rt, struct rt_addrinfo *info, struct route_nhop_data *rnd, struct rib_cmd_info *rc) { struct nhop_object *nh_orig; RIB_WLOCK_ASSERT(rnh); nh_orig = rt->rt_nhop; if (rnd->rnd_nhop != NULL) { /* Changing expiration & nexthop & weight to a new one */ rt_setmetrics(info, rt); rt->rt_nhop = rnd->rnd_nhop; rt->rt_weight = rnd->rnd_weight; if (rt->rt_expire > 0) tmproutes_update(rnh, rt); } else { /* Route deletion requested. */ struct sockaddr *ndst, *netmask; struct radix_node *rn; ndst = (struct sockaddr *)rt_key(rt); netmask = info->rti_info[RTAX_NETMASK]; rn = rnh->rnh_deladdr(ndst, netmask, &rnh->head); if (rn == NULL) return (ESRCH); } /* Finalize notification */ rnh->rnh_gen++; rc->rc_cmd = (rnd->rnd_nhop != NULL) ? RTM_CHANGE : RTM_DELETE; rc->rc_rt = rt; rc->rc_nh_old = nh_orig; rc->rc_nh_new = rnd->rnd_nhop; rc->rc_nh_weight = rnd->rnd_weight; rib_notify(rnh, RIB_NOTIFY_IMMEDIATE, rc); return (0); } /* * Conditionally update route nhop/weight IFF data in @nhd_orig is * consistent with the current route data. * Nexthop in @nhd_new is consumed. */ int change_route_conditional(struct rib_head *rnh, struct rtentry *rt, struct rt_addrinfo *info, struct route_nhop_data *rnd_orig, struct route_nhop_data *rnd_new, struct rib_cmd_info *rc) { struct rtentry *rt_new; int error = 0; RIB_WLOCK(rnh); rt_new = (struct rtentry *)rnh->rnh_lookup(info->rti_info[RTAX_DST], info->rti_info[RTAX_NETMASK], &rnh->head); if (rt_new == NULL) { if (rnd_orig->rnd_nhop == NULL) error = add_route_nhop(rnh, rt, info, rnd_new, rc); else { /* * Prefix does not exist, which was not our assumption. * Update @rnd_orig with the new data and return */ rnd_orig->rnd_nhop = NULL; rnd_orig->rnd_weight = 0; error = EAGAIN; } } else { /* Prefix exists, try to update */ if (rnd_orig->rnd_nhop == rt_new->rt_nhop) { /* * Nhop/mpath group hasn't changed. Flip * to the new precalculated one and return */ error = change_route_nhop(rnh, rt_new, info, rnd_new, rc); } else { /* Update and retry */ rnd_orig->rnd_nhop = rt_new->rt_nhop; rnd_orig->rnd_weight = rt_new->rt_weight; error = EAGAIN; } } RIB_WUNLOCK(rnh); if (error == 0) { rib_notify(rnh, RIB_NOTIFY_DELAYED, rc); if (rnd_orig->rnd_nhop != NULL) nhop_free_any(rnd_orig->rnd_nhop); } else { if (rnd_new->rnd_nhop != NULL) nhop_free_any(rnd_new->rnd_nhop); } return (error); } /* * Performs modification of routing table specificed by @action. * Table is specified by @fibnum and sa_family in @info->rti_info[RTAX_DST]. * Needs to be run in network epoch. * * Returns 0 on success and fills in @rc with action result. */ int rib_action(uint32_t fibnum, int action, struct rt_addrinfo *info, struct rib_cmd_info *rc) { int error; switch (action) { case RTM_ADD: error = rib_add_route(fibnum, info, rc); break; case RTM_DELETE: error = rib_del_route(fibnum, info, rc); break; case RTM_CHANGE: error = rib_change_route(fibnum, info, rc); break; default: error = ENOTSUP; } return (error); } struct rt_delinfo { struct rt_addrinfo info; struct rib_head *rnh; struct rtentry *head; struct rib_cmd_info rc; }; /* * Conditionally unlinks @rn from radix tree based * on info data passed in @arg. */ static int rt_checkdelroute(struct radix_node *rn, void *arg) { struct rt_delinfo *di; struct rt_addrinfo *info; struct rtentry *rt; int error; di = (struct rt_delinfo *)arg; rt = (struct rtentry *)rn; info = &di->info; info->rti_info[RTAX_DST] = rt_key(rt); info->rti_info[RTAX_NETMASK] = rt_mask(rt); info->rti_info[RTAX_GATEWAY] = &rt->rt_nhop->gw_sa; error = rt_unlinkrte(di->rnh, info, &di->rc); /* * Add deleted rtentries to the list to GC them * after dropping the lock. * * XXX: Delayed notifications not implemented * for nexthop updates. */ if (error == 0) { /* Add to the list and return */ rt->rt_chain = di->head; di->head = rt; } return (0); } /* * Iterates over a routing table specified by @fibnum and @family and * deletes elements marked by @filter_f. * @fibnum: rtable id * @family: AF_ address family * @filter_f: function returning non-zero value for items to delete * @arg: data to pass to the @filter_f function * @report: true if rtsock notification is needed. */ void rib_walk_del(u_int fibnum, int family, rt_filter_f_t *filter_f, void *arg, bool report) { struct rib_head *rnh; struct rt_delinfo di; struct rtentry *rt; struct epoch_tracker et; rnh = rt_tables_get_rnh(fibnum, family); if (rnh == NULL) return; bzero(&di, sizeof(di)); di.info.rti_filter = filter_f; di.info.rti_filterdata = arg; di.rnh = rnh; di.rc.rc_cmd = RTM_DELETE; NET_EPOCH_ENTER(et); RIB_WLOCK(rnh); rnh->rnh_walktree(&rnh->head, rt_checkdelroute, &di); RIB_WUNLOCK(rnh); /* We might have something to reclaim. */ bzero(&di.rc, sizeof(di.rc)); di.rc.rc_cmd = RTM_DELETE; while (di.head != NULL) { rt = di.head; di.head = rt->rt_chain; rt->rt_chain = NULL; di.rc.rc_rt = rt; di.rc.rc_nh_old = rt->rt_nhop; rib_notify(rnh, RIB_NOTIFY_DELAYED, &di.rc); /* TODO std rt -> rt_addrinfo export */ di.info.rti_info[RTAX_DST] = rt_key(rt); di.info.rti_info[RTAX_NETMASK] = rt_mask(rt); if (report) rt_routemsg(RTM_DELETE, rt, rt->rt_nhop->nh_ifp, 0, fibnum); rtfree(rt); } NET_EPOCH_EXIT(et); } static void rib_notify(struct rib_head *rnh, enum rib_subscription_type type, struct rib_cmd_info *rc) { struct rib_subscription *rs; CK_STAILQ_FOREACH(rs, &rnh->rnh_subscribers, next) { if (rs->type == type) rs->func(rnh, rc, rs->arg); } } static struct rib_subscription * allocate_subscription(rib_subscription_cb_t *f, void *arg, enum rib_subscription_type type, bool waitok) { struct rib_subscription *rs; int flags = M_ZERO | (waitok ? M_WAITOK : 0); rs = malloc(sizeof(struct rib_subscription), M_RTABLE, flags); if (rs == NULL) return (NULL); rs->func = f; rs->arg = arg; rs->type = type; return (rs); } /* * Subscribe for the changes in the routing table specified by @fibnum and * @family. * * Returns pointer to the subscription structure on success. */ struct rib_subscription * rib_subscribe(uint32_t fibnum, int family, rib_subscription_cb_t *f, void *arg, enum rib_subscription_type type, bool waitok) { struct rib_head *rnh; struct rib_subscription *rs; struct epoch_tracker et; if ((rs = allocate_subscription(f, arg, type, waitok)) == NULL) return (NULL); NET_EPOCH_ENTER(et); KASSERT((fibnum < rt_numfibs), ("%s: bad fibnum", __func__)); rnh = rt_tables_get_rnh(fibnum, family); RIB_WLOCK(rnh); CK_STAILQ_INSERT_TAIL(&rnh->rnh_subscribers, rs, next); RIB_WUNLOCK(rnh); NET_EPOCH_EXIT(et); return (rs); } struct rib_subscription * rib_subscribe_internal(struct rib_head *rnh, rib_subscription_cb_t *f, void *arg, enum rib_subscription_type type, bool waitok) { struct rib_subscription *rs; struct epoch_tracker et; if ((rs = allocate_subscription(f, arg, type, waitok)) == NULL) return (NULL); NET_EPOCH_ENTER(et); RIB_WLOCK(rnh); CK_STAILQ_INSERT_TAIL(&rnh->rnh_subscribers, rs, next); RIB_WUNLOCK(rnh); NET_EPOCH_EXIT(et); return (rs); } /* * Remove rtable subscription @rs from the table specified by @fibnum * and @family. * Needs to be run in network epoch. * * Returns 0 on success. */ int rib_unsibscribe(uint32_t fibnum, int family, struct rib_subscription *rs) { struct rib_head *rnh; NET_EPOCH_ASSERT(); KASSERT((fibnum < rt_numfibs), ("%s: bad fibnum", __func__)); rnh = rt_tables_get_rnh(fibnum, family); if (rnh == NULL) return (ENOENT); RIB_WLOCK(rnh); CK_STAILQ_REMOVE(&rnh->rnh_subscribers, rs, rib_subscription, next); RIB_WUNLOCK(rnh); epoch_call(net_epoch_preempt, destroy_subscription_epoch, &rs->epoch_ctx); return (0); } /* * Epoch callback indicating subscription is safe to destroy */ static void destroy_subscription_epoch(epoch_context_t ctx) { struct rib_subscription *rs; rs = __containerof(ctx, struct rib_subscription, epoch_ctx); free(rs, M_RTABLE); } void rib_init_subscriptions(struct rib_head *rnh) { CK_STAILQ_INIT(&rnh->rnh_subscribers); } void rib_destroy_subscriptions(struct rib_head *rnh) { struct rib_subscription *rs; struct epoch_tracker et; NET_EPOCH_ENTER(et); RIB_WLOCK(rnh); while ((rs = CK_STAILQ_FIRST(&rnh->rnh_subscribers)) != NULL) { CK_STAILQ_REMOVE_HEAD(&rnh->rnh_subscribers, next); epoch_call(net_epoch_preempt, destroy_subscription_epoch, &rs->epoch_ctx); } RIB_WUNLOCK(rnh); NET_EPOCH_EXIT(et); }