1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2020 Alexander V. Chernikov 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 /* 29 * This file contains code responsible for expiring temporal routes 30 * (typically, redirect-originated) from the route tables. 31 */ 32 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/socket.h> 39 #include <sys/kernel.h> 40 #include <sys/lock.h> 41 #include <sys/ck.h> 42 #include <sys/rmlock.h> 43 #include <sys/callout.h> 44 45 #include <net/if.h> 46 #include <net/route.h> 47 #include <net/route/route_ctl.h> 48 #include <net/route/route_var.h> 49 #include <net/vnet.h> 50 51 /* 52 * Callback returning 1 for the expired routes. 53 * Updates time of the next nearest route expiration as a side effect. 54 */ 55 static int 56 expire_route(const struct rtentry *rt, const struct nhop_object *nh, void *arg) 57 { 58 time_t *next_callout; 59 60 if (rt->rt_expire == 0) 61 return (0); 62 63 if (rt->rt_expire <= time_uptime) 64 return (1); 65 66 next_callout = (time_t *)arg; 67 68 /* 69 * Update next_callout to determine the next ts to 70 * run the callback at. 71 */ 72 if (*next_callout == 0 || *next_callout > rt->rt_expire) 73 *next_callout = rt->rt_expire; 74 75 return (0); 76 } 77 78 /* 79 * Per-rnh callout function traversing the tree and deleting 80 * expired routes. Calculates next callout run by looking at 81 * the rt_expire time for the remaining temporal routes. 82 */ 83 static void 84 expire_callout(void *arg) 85 { 86 struct rib_head *rnh; 87 time_t next_expire; 88 int seconds; 89 90 rnh = (struct rib_head *)arg; 91 92 CURVNET_SET(rnh->rib_vnet); 93 next_expire = 0; 94 95 rib_walk_del(rnh->rib_fibnum, rnh->rib_family, expire_route, 96 (void *)&next_expire, 1); 97 98 RIB_WLOCK(rnh); 99 if (next_expire > 0) { 100 seconds = (next_expire - time_uptime); 101 if (seconds < 0) 102 seconds = 0; 103 callout_reset_sbt(&rnh->expire_callout, SBT_1S * seconds, 104 SBT_1MS * 500, expire_callout, rnh, 0); 105 rnh->next_expire = next_expire; 106 } else { 107 /* 108 * Before resetting next_expire, check that tmproutes_update() 109 * has not kicked in and scheduled another invocation. 110 */ 111 if (callout_pending(&rnh->expire_callout) == 0) 112 rnh->next_expire = 0; 113 } 114 RIB_WUNLOCK(rnh); 115 CURVNET_RESTORE(); 116 } 117 118 /* 119 * Function responsible for updating the time of the next calllout 120 * w.r.t. new temporal routes insertion. 121 * 122 * Called by the routing code upon adding new temporal route 123 * to the tree. RIB_WLOCK must be held. 124 */ 125 void 126 tmproutes_update(struct rib_head *rnh, struct rtentry *rt) 127 { 128 int seconds; 129 130 RIB_WLOCK_ASSERT(rnh); 131 132 if (rnh->next_expire == 0 || rnh->next_expire > rt->rt_expire) { 133 /* 134 * Callback is not scheduled, is executing, 135 * or is scheduled for a later time than we need. 136 * 137 * Schedule the one for the current @rt expiration time. 138 */ 139 seconds = (rt->rt_expire - time_uptime); 140 if (seconds < 0) 141 seconds = 0; 142 callout_reset_sbt(&rnh->expire_callout, SBT_1S * seconds, 143 SBT_1MS * 500, expire_callout, rnh, 0); 144 145 rnh->next_expire = rt->rt_expire; 146 } 147 } 148 149 void 150 tmproutes_init(struct rib_head *rh) 151 { 152 153 callout_init(&rh->expire_callout, 1); 154 } 155 156 157 void 158 tmproutes_destroy(struct rib_head *rh) 159 { 160 161 callout_drain(&rh->expire_callout); 162 } 163 164