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