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 */
33
34 #include "opt_route.h"
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/malloc.h>
39 #include <sys/socket.h>
40 #include <sys/sysctl.h>
41 #include <sys/syslog.h>
42 #include <sys/kernel.h>
43 #include <sys/lock.h>
44 #include <sys/rmlock.h>
45
46 #include <net/if.h>
47 #include <net/if_var.h>
48 #include <net/if_private.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
rib_handle_ifaddr_one(uint32_t fibnum,int cmd,struct rt_addrinfo * info)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
rib_handle_ifaddr_info(uint32_t fibnum,int cmd,struct rt_addrinfo * info)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
ifa_maintain_loopback_route(int cmd,const char * otype,struct ifaddr * ifa,struct sockaddr * ia)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
ifa_add_loopback_route(struct ifaddr * ifa,struct sockaddr * ia)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
ifa_del_loopback_route(struct ifaddr * ifa,struct sockaddr * ia)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
ifa_switch_loopback_route(struct ifaddr * ifa,struct sockaddr * ia)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
match_kernel_route(const struct rtentry * rt,struct nhop_object * nh)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
pick_kernel_route(struct rtentry * rt,void * arg)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
rib_copy_kernel_routes(struct rib_head * rh_src,struct rib_head * rh_dst)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