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
32 #include "opt_route.h"
33
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/malloc.h>
37 #include <sys/socket.h>
38 #include <sys/sysctl.h>
39 #include <sys/syslog.h>
40 #include <sys/kernel.h>
41 #include <sys/lock.h>
42 #include <sys/rmlock.h>
43
44 #include <net/if.h>
45 #include <net/if_var.h>
46 #include <net/if_private.h>
47 #include <net/if_dl.h>
48 #include <net/route.h>
49 #include <net/route/route_ctl.h>
50 #include <net/route/route_var.h>
51 #include <net/route/nhop.h>
52 #include <net/vnet.h>
53
54 #include <netinet/in.h>
55
56 /*
57 * Control interface address fib propagation.
58 * By default, interface address routes are added to the fib of the interface.
59 * Once set to non-zero, adds interface address route to all fibs.
60 */
61 VNET_DEFINE(u_int, rt_add_addr_allfibs) = 0;
62 SYSCTL_UINT(_net, OID_AUTO, add_addr_allfibs, CTLFLAG_RWTUN | CTLFLAG_VNET,
63 &VNET_NAME(rt_add_addr_allfibs), 0, "");
64
65 /*
66 * Executes routing tables change specified by @cmd and @info for the fib
67 * @fibnum. Generates routing message on success.
68 * Note: it assumes there is only single route (interface route) for the
69 * provided prefix.
70 * Returns 0 on success or errno.
71 */
72 static int
rib_handle_ifaddr_one(uint32_t fibnum,int cmd,struct rt_addrinfo * info)73 rib_handle_ifaddr_one(uint32_t fibnum, int cmd, struct rt_addrinfo *info)
74 {
75 struct rib_cmd_info rc;
76 struct nhop_object *nh;
77 int error;
78
79 error = rib_action(fibnum, cmd, info, &rc);
80 if (error == 0) {
81 if (cmd == RTM_ADD)
82 nh = nhop_select(rc.rc_nh_new, 0);
83 else
84 nh = nhop_select(rc.rc_nh_old, 0);
85 rt_routemsg(cmd, rc.rc_rt, nh, fibnum);
86 }
87
88 return (error);
89 }
90
91 /*
92 * Adds/deletes interface prefix specified by @info to the routing table.
93 * If V_rt_add_addr_allfibs is set, iterates over all existing routing
94 * tables, otherwise uses fib in @fibnum. Generates routing message for
95 * each table.
96 * Returns 0 on success or errno.
97 */
98 int
rib_handle_ifaddr_info(uint32_t fibnum,int cmd,struct rt_addrinfo * info)99 rib_handle_ifaddr_info(uint32_t fibnum, int cmd, struct rt_addrinfo *info)
100 {
101 int error = 0, last_error = 0;
102 bool didwork = false;
103
104 if (V_rt_add_addr_allfibs == 0) {
105 error = rib_handle_ifaddr_one(fibnum, cmd, info);
106 didwork = (error == 0);
107 } else {
108 for (fibnum = 0; fibnum < V_rt_numfibs; fibnum++) {
109 error = rib_handle_ifaddr_one(fibnum, cmd, info);
110 if (error == 0)
111 didwork = true;
112 else
113 last_error = error;
114 }
115 }
116
117 if (cmd == RTM_DELETE) {
118 if (didwork) {
119 error = 0;
120 } else {
121 /* we only give an error if it wasn't in any table */
122 error = ((info->rti_flags & RTF_HOST) ?
123 EHOSTUNREACH : ENETUNREACH);
124 }
125 } else {
126 if (last_error != 0) {
127 /* return an error if any of them failed */
128 error = last_error;
129 }
130 }
131 return (error);
132 }
133
134 static int
ifa_maintain_loopback_route(int cmd,const char * otype,struct ifaddr * ifa,struct sockaddr * ia)135 ifa_maintain_loopback_route(int cmd, const char *otype, struct ifaddr *ifa,
136 struct sockaddr *ia)
137 {
138 struct rib_cmd_info rc;
139 struct epoch_tracker et;
140 int error;
141 struct rt_addrinfo info;
142 struct sockaddr_dl null_sdl;
143 struct ifnet *ifp;
144
145 ifp = ifa->ifa_ifp;
146
147 NET_EPOCH_ENTER(et);
148 bzero(&info, sizeof(info));
149 if (cmd != RTM_DELETE)
150 info.rti_ifp = V_loif;
151 if (cmd == RTM_ADD) {
152 /* explicitly specify (loopback) ifa */
153 if (info.rti_ifp != NULL)
154 info.rti_ifa = ifaof_ifpforaddr(ifa->ifa_addr, info.rti_ifp);
155 }
156 info.rti_flags = ifa->ifa_flags | RTF_HOST | RTF_STATIC | RTF_PINNED;
157 info.rti_info[RTAX_DST] = ia;
158 info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&null_sdl;
159 link_init_sdl(ifp, (struct sockaddr *)&null_sdl, ifp->if_type);
160
161 error = rib_action(ifp->if_fib, cmd, &info, &rc);
162 NET_EPOCH_EXIT(et);
163
164 if (error == 0 ||
165 (cmd == RTM_ADD && error == EEXIST) ||
166 (cmd == RTM_DELETE && (error == ENOENT || error == ESRCH)))
167 return (error);
168
169 log(LOG_DEBUG, "%s: %s failed for interface %s: %u\n",
170 __func__, otype, if_name(ifp), error);
171
172 return (error);
173 }
174
175 int
ifa_add_loopback_route(struct ifaddr * ifa,struct sockaddr * ia)176 ifa_add_loopback_route(struct ifaddr *ifa, struct sockaddr *ia)
177 {
178
179 return (ifa_maintain_loopback_route(RTM_ADD, "insertion", ifa, ia));
180 }
181
182 int
ifa_del_loopback_route(struct ifaddr * ifa,struct sockaddr * ia)183 ifa_del_loopback_route(struct ifaddr *ifa, struct sockaddr *ia)
184 {
185
186 return (ifa_maintain_loopback_route(RTM_DELETE, "deletion", ifa, ia));
187 }
188
189 int
ifa_switch_loopback_route(struct ifaddr * ifa,struct sockaddr * ia)190 ifa_switch_loopback_route(struct ifaddr *ifa, struct sockaddr *ia)
191 {
192
193 return (ifa_maintain_loopback_route(RTM_CHANGE, "switch", ifa, ia));
194 }
195
196 static bool
match_kernel_route(const struct rtentry * rt,struct nhop_object * nh)197 match_kernel_route(const struct rtentry *rt, struct nhop_object *nh)
198 {
199 if (!NH_IS_NHGRP(nh) && (nhop_get_rtflags(nh) & RTF_PINNED) &&
200 nh->nh_aifp->if_fib == nhop_get_fibnum(nh))
201 return (true);
202 return (false);
203 }
204
205 static int
pick_kernel_route(struct rtentry * rt,void * arg)206 pick_kernel_route(struct rtentry *rt, void *arg)
207 {
208 struct nhop_object *nh = rt->rt_nhop;
209 struct rib_head *rh_dst = (struct rib_head *)arg;
210
211 if (match_kernel_route(rt, nh)) {
212 struct rib_cmd_info rc = {};
213 struct route_nhop_data rnd = {
214 .rnd_nhop = nh,
215 .rnd_weight = rt->rt_weight,
216 };
217 rib_copy_route(rt, &rnd, rh_dst, &rc);
218 }
219 return (0);
220 }
221
222 /*
223 * Tries to copy kernel routes matching pattern from @rh_src to @rh_dst.
224 *
225 * Note: as this function acquires locks for both @rh_src and @rh_dst,
226 * it needs to be called under RTABLES_LOCK() to avoid deadlocking
227 * with multiple ribs.
228 */
229 void
rib_copy_kernel_routes(struct rib_head * rh_src,struct rib_head * rh_dst)230 rib_copy_kernel_routes(struct rib_head *rh_src, struct rib_head *rh_dst)
231 {
232 struct epoch_tracker et;
233
234 if (V_rt_add_addr_allfibs == 0)
235 return;
236
237 NET_EPOCH_ENTER(et);
238 rib_walk_ext_internal(rh_src, false, pick_kernel_route, NULL, rh_dst);
239 NET_EPOCH_EXIT(et);
240 }
241
242