diff options
Diffstat (limited to 'sys/net/route.c')
| -rw-r--r-- | sys/net/route.c | 706 |
1 files changed, 706 insertions, 0 deletions
diff --git a/sys/net/route.c b/sys/net/route.c new file mode 100644 index 000000000000..d2c9f3e39c17 --- /dev/null +++ b/sys/net/route.c @@ -0,0 +1,706 @@ +/*- + * 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. + */ +/************************************************************************ + * 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/devctl.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_private.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> +#include <netinet6/in6_var.h> + +VNET_PCPUSTAT_DEFINE(struct rtstat, rtstat); + +VNET_PCPUSTAT_SYSINIT(rtstat); +#ifdef VIMAGE +VNET_PCPUSTAT_SYSUNINIT(rtstat); +#endif + +SYSCTL_DECL(_net_route); +SYSCTL_VNET_PCPUSTAT(_net_route, OID_AUTO, stats, struct rtstat, + rtstat, "route statistics"); + +EVENTHANDLER_LIST_DEFINE(rt_addrmsg); + +static int rt_ifdelroute(const struct rtentry *rt, const struct nhop_object *, + void *arg); + +/* + * route initialization must occur before ip6_init2(), which happenas at + * SI_ORDER_MIDDLE. + */ +static void +route_init(void *dummy __unused) +{ + + 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 route_nhop_data rnd = { .rnd_weight = RT_DEFAULT_WEIGHT }; + struct rib_cmd_info rc; + struct ifaddr *ifa; + int error; + + 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); + + struct nhop_object *nh = nhop_alloc(fibnum, dst->sa_family); + if (nh == NULL) + return (ENOMEM); + + nhop_set_gw(nh, gateway, flags & RTF_GATEWAY); + nhop_set_transmit_ifp(nh, ifp); + nhop_set_src(nh, ifa); + nhop_set_pxtype_flag(nh, NHF_HOST); + nhop_set_expire(nh, lifetime_sec + time_uptime); + nhop_set_redirect(nh, true); + nhop_set_origin(nh, NH_ORIGIN_REDIRECT); + rnd.rnd_nhop = nhop_get_nhop(nh, &error); + if (error == 0) { + error = rib_add_route_px(fibnum, dst, -1, + &rnd, RTM_F_CREATE, &rc); + } + + if (error != 0) { + /* TODO: add per-fib redirect stats. */ + return (error); + } + + RTSTAT_INC(rts_dynamic); + + /* Send notification of a route addition to userland. */ + struct rt_addrinfo info = { + .rti_info[RTAX_DST] = dst, + .rti_info[RTAX_GATEWAY] = gateway, + .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); +} + +/* + * 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); +} + +void +rt_flushifroutes(struct ifnet *ifp) +{ + + rib_foreach_table_walk_del(AF_UNSPEC, rt_ifdelroute, ifp); +} + +/* + * Tries to extract interface from RTAX_IFP passed in rt_addrinfo. + * Interface can be specified ether as interface index (sdl_index) or + * the interface name (sdl_data). + * + * Returns found ifp or NULL + */ +static struct ifnet * +info_get_ifp(struct rt_addrinfo *info) +{ + const struct sockaddr_dl *sdl; + + sdl = (const struct sockaddr_dl *)info->rti_info[RTAX_IFP]; + if (sdl->sdl_family != AF_LINK) + return (NULL); + + if (sdl->sdl_index != 0) + return (ifnet_byindex(sdl->sdl_index)); + if (sdl->sdl_nlen > 0) { + char if_name[IF_NAMESIZE]; + if (sdl->sdl_nlen + offsetof(struct sockaddr_dl, sdl_data) > sdl->sdl_len) + return (NULL); + if (sdl->sdl_nlen >= IF_NAMESIZE) + return (NULL); + bzero(if_name, sizeof(if_name)); + memcpy(if_name, sdl->sdl_data, sdl->sdl_nlen); + return (ifunit(if_name)); + } + + return (NULL); +} + +/* + * Calculates proper ifa/ifp for the cases when gateway AF is different + * from dst AF. + * + * Returns 0 on success. + */ +__noinline static int +rt_getifa_family(struct rt_addrinfo *info, uint32_t fibnum) +{ + if (info->rti_ifp == NULL) { + struct ifaddr *ifa = NULL; + /* + * No transmit interface specified. Guess it by checking gw sa. + */ + const struct sockaddr *gw = info->rti_info[RTAX_GATEWAY]; + ifa = ifa_ifwithroute(RTF_GATEWAY, gw, gw, fibnum); + if (ifa == NULL) + return (ENETUNREACH); + info->rti_ifp = ifa->ifa_ifp; + } + + /* Prefer address from outgoing interface */ + info->rti_ifa = ifaof_ifpforaddr(info->rti_info[RTAX_DST], info->rti_ifp); +#ifdef INET + if (info->rti_ifa == NULL) { + /* Use first found IPv4 address */ + bool loopback_ok = info->rti_ifp->if_flags & IFF_LOOPBACK; + info->rti_ifa = (struct ifaddr *)in_findlocal(fibnum, loopback_ok); + } +#endif + if (info->rti_ifa == NULL) + return (ENETUNREACH); + return (0); +} + +/* + * Fills in rti_ifp and rti_ifa for the provided fib. + * + * 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, *ifaaddr; + int error, flags; + + dst = info->rti_info[RTAX_DST]; + gateway = info->rti_info[RTAX_GATEWAY]; + ifaaddr = info->rti_info[RTAX_IFA]; + flags = info->rti_flags; + + /* + * ifp may be specified by sockaddr_dl + * when protocol address is ambiguous. + */ + error = 0; + + /* If we have interface specified by RTAX_IFP address, try to use it */ + if ((info->rti_ifp == NULL) && (info->rti_info[RTAX_IFP] != NULL)) + info->rti_ifp = info_get_ifp(info); + /* + * 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) && ((info->rti_flags & RTF_GATEWAY) != 0) && + (gateway->sa_family != dst->sa_family)) + return (rt_getifa_family(info, fibnum)); + 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 (info->rti_ifa != NULL) { + if (info->rti_ifp == NULL) + info->rti_ifp = info->rti_ifa->ifa_ifp; + } else + error = ENETUNREACH; + 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(const struct sockaddr *src, struct sockaddr *dst, + const struct sockaddr *netmask) +{ + const u_char *cp1 = (const u_char *)src; + u_char *cp2 = (u_char *)dst; + const u_char *cp3 = (const 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) +{ +#if defined(INET) || defined(INET6) + struct sockaddr *sa = ifa->ifa_addr; + struct ifnet *ifp = ifa->ifa_ifp; +#endif + + 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); + +#ifdef INET + if (sa->sa_family == AF_INET) { + char addrstr[INET_ADDRSTRLEN]; + char strbuf[INET_ADDRSTRLEN + 12]; + + inet_ntoa_r(((struct sockaddr_in *)sa)->sin_addr, addrstr); + snprintf(strbuf, sizeof(strbuf), "address=%s", addrstr); + devctl_notify("IFNET", ifp->if_xname, + (cmd == RTM_ADD) ? "ADDR_ADD" : "ADDR_DEL", strbuf); + } +#endif +#ifdef INET6 + if (sa->sa_family == AF_INET6) { + char addrstr[INET6_ADDRSTRLEN]; + char strbuf[INET6_ADDRSTRLEN + 12]; + + ip6_sprintf(addrstr, IFA_IN6(ifa)); + snprintf(strbuf, sizeof(strbuf), "address=%s", addrstr); + devctl_notify("IFNET", ifp->if_xname, + (cmd == RTM_ADD) ? "ADDR_ADD" : "ADDR_DEL", strbuf); + } +#endif + + 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 || 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(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)); +} + +void +rt_ifmsg(struct ifnet *ifp, int if_flags_mask) +{ + rtsock_callback_p->ifmsg_f(ifp, if_flags_mask); + netlink_callback_p->ifmsg_f(ifp, if_flags_mask); +} + |