/*- * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include 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)); }