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 uint32_t nh_expire = nhop_get_expire(nh); 59 time_t *next_callout; 60 61 if (nh_expire == 0) 62 return (0); 63 64 if (nh_expire <= time_uptime) 65 return (1); 66 67 next_callout = (time_t *)arg; 68 69 /* 70 * Update next_callout to determine the next ts to 71 * run the callback at. 72 */ 73 if (*next_callout == 0 || *next_callout > nh_expire) 74 *next_callout = nh_expire; 75 76 return (0); 77 } 78 79 /* 80 * Per-rnh callout function traversing the tree and deleting 81 * expired routes. Calculates next callout run by looking at 82 * the nh_expire time for the remaining temporal routes. 83 */ 84 static void 85 expire_callout(void *arg) 86 { 87 struct rib_head *rnh; 88 time_t next_expire; 89 int seconds; 90 91 rnh = (struct rib_head *)arg; 92 93 CURVNET_SET(rnh->rib_vnet); 94 next_expire = 0; 95 96 rib_walk_del(rnh->rib_fibnum, rnh->rib_family, expire_route, 97 (void *)&next_expire, 1); 98 99 RIB_WLOCK(rnh); 100 if (next_expire > 0) { 101 seconds = (next_expire - time_uptime); 102 if (seconds < 0) 103 seconds = 0; 104 callout_reset_sbt(&rnh->expire_callout, SBT_1S * seconds, 105 SBT_1MS * 500, expire_callout, rnh, 0); 106 rnh->next_expire = next_expire; 107 } else { 108 /* 109 * Before resetting next_expire, check that tmproutes_update() 110 * has not kicked in and scheduled another invocation. 111 */ 112 if (callout_pending(&rnh->expire_callout) == 0) 113 rnh->next_expire = 0; 114 } 115 RIB_WUNLOCK(rnh); 116 CURVNET_RESTORE(); 117 } 118 119 /* 120 * Function responsible for updating the time of the next calllout 121 * w.r.t. new temporal routes insertion. 122 * 123 * Called by the routing code upon adding new temporal route 124 * to the tree. RIB_WLOCK must be held. 125 */ 126 void 127 tmproutes_update(struct rib_head *rnh, struct rtentry *rt, struct nhop_object *nh) 128 { 129 int seconds; 130 uint32_t nh_expire = nhop_get_expire(nh); 131 132 RIB_WLOCK_ASSERT(rnh); 133 134 if (rnh->next_expire == 0 || rnh->next_expire > nh_expire) { 135 /* 136 * Callback is not scheduled, is executing, 137 * or is scheduled for a later time than we need. 138 * 139 * Schedule the one for the current @rt expiration time. 140 */ 141 seconds = (nh_expire - time_uptime); 142 if (seconds < 0) 143 seconds = 0; 144 callout_reset_sbt(&rnh->expire_callout, SBT_1S * seconds, 145 SBT_1MS * 500, expire_callout, rnh, 0); 146 147 rnh->next_expire = nh_expire; 148 } 149 } 150 151 void 152 tmproutes_init(struct rib_head *rh) 153 { 154 155 callout_init(&rh->expire_callout, 1); 156 } 157 158 void 159 tmproutes_destroy(struct rib_head *rh) 160 { 161 162 callout_drain(&rh->expire_callout); 163 } 164