1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1980, 1986, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)route.c 8.3.1.1 (Berkeley) 2/23/95 32 * $FreeBSD$ 33 */ 34 35 #include "opt_route.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/malloc.h> 40 #include <sys/socket.h> 41 #include <sys/sysctl.h> 42 #include <sys/syslog.h> 43 #include <sys/kernel.h> 44 #include <sys/lock.h> 45 #include <sys/rmlock.h> 46 47 #include <net/if.h> 48 #include <net/if_var.h> 49 #include <net/if_dl.h> 50 #include <net/route.h> 51 #include <net/route/route_ctl.h> 52 #include <net/route/route_var.h> 53 #include <net/route/nhop.h> 54 #include <net/vnet.h> 55 56 #include <netinet/in.h> 57 58 /* 59 * Control interface address fib propagation. 60 * By default, interface address routes are added to the fib of the interface. 61 * Once set to non-zero, adds interface address route to all fibs. 62 */ 63 VNET_DEFINE(u_int, rt_add_addr_allfibs) = 0; 64 SYSCTL_UINT(_net, OID_AUTO, add_addr_allfibs, CTLFLAG_RWTUN | CTLFLAG_VNET, 65 &VNET_NAME(rt_add_addr_allfibs), 0, ""); 66 67 /* 68 * Executes routing tables change specified by @cmd and @info for the fib 69 * @fibnum. Generates routing message on success. 70 * Note: it assumes there is only single route (interface route) for the 71 * provided prefix. 72 * Returns 0 on success or errno. 73 */ 74 static int 75 rib_handle_ifaddr_one(uint32_t fibnum, int cmd, struct rt_addrinfo *info) 76 { 77 struct rib_cmd_info rc; 78 struct nhop_object *nh; 79 int error; 80 81 error = rib_action(fibnum, cmd, info, &rc); 82 if (error == 0) { 83 if (cmd == RTM_ADD) 84 nh = nhop_select(rc.rc_nh_new, 0); 85 else 86 nh = nhop_select(rc.rc_nh_old, 0); 87 rt_routemsg(cmd, rc.rc_rt, nh, fibnum); 88 } 89 90 return (error); 91 } 92 93 /* 94 * Adds/deletes interface prefix specified by @info to the routing table. 95 * If V_rt_add_addr_allfibs is set, iterates over all existing routing 96 * tables, otherwise uses fib in @fibnum. Generates routing message for 97 * each table. 98 * Returns 0 on success or errno. 99 */ 100 int 101 rib_handle_ifaddr_info(uint32_t fibnum, int cmd, struct rt_addrinfo *info) 102 { 103 int error = 0, last_error = 0; 104 bool didwork = false; 105 106 if (V_rt_add_addr_allfibs == 0) { 107 error = rib_handle_ifaddr_one(fibnum, cmd, info); 108 didwork = (error == 0); 109 } else { 110 for (fibnum = 0; fibnum < V_rt_numfibs; fibnum++) { 111 error = rib_handle_ifaddr_one(fibnum, cmd, info); 112 if (error == 0) 113 didwork = true; 114 else 115 last_error = error; 116 } 117 } 118 119 if (cmd == RTM_DELETE) { 120 if (didwork) { 121 error = 0; 122 } else { 123 /* we only give an error if it wasn't in any table */ 124 error = ((info->rti_flags & RTF_HOST) ? 125 EHOSTUNREACH : ENETUNREACH); 126 } 127 } else { 128 if (last_error != 0) { 129 /* return an error if any of them failed */ 130 error = last_error; 131 } 132 } 133 return (error); 134 } 135 136 static int 137 ifa_maintain_loopback_route(int cmd, const char *otype, struct ifaddr *ifa, 138 struct sockaddr *ia) 139 { 140 struct rib_cmd_info rc; 141 struct epoch_tracker et; 142 int error; 143 struct rt_addrinfo info; 144 struct sockaddr_dl null_sdl; 145 struct ifnet *ifp; 146 147 ifp = ifa->ifa_ifp; 148 149 NET_EPOCH_ENTER(et); 150 bzero(&info, sizeof(info)); 151 if (cmd != RTM_DELETE) 152 info.rti_ifp = V_loif; 153 if (cmd == RTM_ADD) { 154 /* explicitly specify (loopback) ifa */ 155 if (info.rti_ifp != NULL) 156 info.rti_ifa = ifaof_ifpforaddr(ifa->ifa_addr, info.rti_ifp); 157 } 158 info.rti_flags = ifa->ifa_flags | RTF_HOST | RTF_STATIC | RTF_PINNED; 159 info.rti_info[RTAX_DST] = ia; 160 info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&null_sdl; 161 link_init_sdl(ifp, (struct sockaddr *)&null_sdl, ifp->if_type); 162 163 error = rib_action(ifp->if_fib, cmd, &info, &rc); 164 NET_EPOCH_EXIT(et); 165 166 if (error == 0 || 167 (cmd == RTM_ADD && error == EEXIST) || 168 (cmd == RTM_DELETE && (error == ENOENT || error == ESRCH))) 169 return (error); 170 171 log(LOG_DEBUG, "%s: %s failed for interface %s: %u\n", 172 __func__, otype, if_name(ifp), error); 173 174 return (error); 175 } 176 177 int 178 ifa_add_loopback_route(struct ifaddr *ifa, struct sockaddr *ia) 179 { 180 181 return (ifa_maintain_loopback_route(RTM_ADD, "insertion", ifa, ia)); 182 } 183 184 int 185 ifa_del_loopback_route(struct ifaddr *ifa, struct sockaddr *ia) 186 { 187 188 return (ifa_maintain_loopback_route(RTM_DELETE, "deletion", ifa, ia)); 189 } 190 191 int 192 ifa_switch_loopback_route(struct ifaddr *ifa, struct sockaddr *ia) 193 { 194 195 return (ifa_maintain_loopback_route(RTM_CHANGE, "switch", ifa, ia)); 196 } 197 198 static bool 199 match_kernel_route(const struct rtentry *rt, struct nhop_object *nh) 200 { 201 if (!NH_IS_NHGRP(nh) && (nhop_get_rtflags(nh) & RTF_PINNED) && 202 nh->nh_aifp->if_fib == nhop_get_fibnum(nh)) 203 return (true); 204 return (false); 205 } 206 207 static int 208 pick_kernel_route(struct rtentry *rt, void *arg) 209 { 210 struct nhop_object *nh = rt->rt_nhop; 211 struct rib_head *rh_dst = (struct rib_head *)arg; 212 213 if (match_kernel_route(rt, nh)) { 214 struct rib_cmd_info rc = {}; 215 struct route_nhop_data rnd = { 216 .rnd_nhop = nh, 217 .rnd_weight = rt->rt_weight, 218 }; 219 rib_copy_route(rt, &rnd, rh_dst, &rc); 220 } 221 return (0); 222 } 223 224 /* 225 * Tries to copy kernel routes matching pattern from @rh_src to @rh_dst. 226 * 227 * Note: as this function acquires locks for both @rh_src and @rh_dst, 228 * it needs to be called under RTABLES_LOCK() to avoid deadlocking 229 * with multiple ribs. 230 */ 231 void 232 rib_copy_kernel_routes(struct rib_head *rh_src, struct rib_head *rh_dst) 233 { 234 struct epoch_tracker et; 235 236 if (V_rt_add_addr_allfibs == 0) 237 return; 238 239 NET_EPOCH_ENTER(et); 240 rib_walk_ext_internal(rh_src, false, pick_kernel_route, NULL, rh_dst); 241 NET_EPOCH_EXIT(et); 242 } 243 244