1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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/param.h> 34 #include <sys/systm.h> 35 #include <sys/socket.h> 36 #include <sys/kernel.h> 37 #include <sys/lock.h> 38 #include <sys/ck.h> 39 #include <sys/rmlock.h> 40 #include <sys/callout.h> 41 42 #include <net/if.h> 43 #include <net/route.h> 44 #include <net/route/route_ctl.h> 45 #include <net/route/route_var.h> 46 #include <net/vnet.h> 47 48 /* 49 * Callback returning 1 for the expired routes. 50 * Updates time of the next nearest route expiration as a side effect. 51 */ 52 static int 53 expire_route(const struct rtentry *rt, const struct nhop_object *nh, void *arg) 54 { 55 uint32_t nh_expire = nhop_get_expire(nh); 56 time_t *next_callout; 57 58 if (nh_expire == 0) 59 return (0); 60 61 if (nh_expire <= time_uptime) 62 return (1); 63 64 next_callout = (time_t *)arg; 65 66 /* 67 * Update next_callout to determine the next ts to 68 * run the callback at. 69 */ 70 if (*next_callout == 0 || *next_callout > nh_expire) 71 *next_callout = nh_expire; 72 73 return (0); 74 } 75 76 /* 77 * Per-rnh callout function traversing the tree and deleting 78 * expired routes. Calculates next callout run by looking at 79 * the nh_expire time for the remaining temporal routes. 80 */ 81 static void 82 expire_callout(void *arg) 83 { 84 struct rib_head *rnh; 85 time_t next_expire; 86 int seconds; 87 88 rnh = (struct rib_head *)arg; 89 90 CURVNET_SET(rnh->rib_vnet); 91 next_expire = 0; 92 93 rib_walk_del(rnh->rib_fibnum, rnh->rib_family, expire_route, 94 (void *)&next_expire, 1); 95 96 RIB_WLOCK(rnh); 97 if (next_expire > 0) { 98 seconds = (next_expire - time_uptime); 99 if (seconds < 0) 100 seconds = 0; 101 callout_reset_sbt(&rnh->expire_callout, SBT_1S * seconds, 102 SBT_1MS * 500, expire_callout, rnh, 0); 103 rnh->next_expire = next_expire; 104 } else { 105 /* 106 * Before resetting next_expire, check that tmproutes_update() 107 * has not kicked in and scheduled another invocation. 108 */ 109 if (callout_pending(&rnh->expire_callout) == 0) 110 rnh->next_expire = 0; 111 } 112 RIB_WUNLOCK(rnh); 113 CURVNET_RESTORE(); 114 } 115 116 /* 117 * Function responsible for updating the time of the next calllout 118 * w.r.t. new temporal routes insertion. 119 * 120 * Called by the routing code upon adding new temporal route 121 * to the tree. RIB_WLOCK must be held. 122 */ 123 void 124 tmproutes_update(struct rib_head *rnh, struct rtentry *rt, struct nhop_object *nh) 125 { 126 int seconds; 127 uint32_t nh_expire = nhop_get_expire(nh); 128 129 RIB_WLOCK_ASSERT(rnh); 130 131 if (rnh->next_expire == 0 || rnh->next_expire > nh_expire) { 132 /* 133 * Callback is not scheduled, is executing, 134 * or is scheduled for a later time than we need. 135 * 136 * Schedule the one for the current @rt expiration time. 137 */ 138 seconds = (nh_expire - time_uptime); 139 if (seconds < 0) 140 seconds = 0; 141 callout_reset_sbt(&rnh->expire_callout, SBT_1S * seconds, 142 SBT_1MS * 500, expire_callout, rnh, 0); 143 144 rnh->next_expire = nh_expire; 145 } 146 } 147 148 void 149 tmproutes_init(struct rib_head *rh) 150 { 151 152 callout_init(&rh->expire_callout, 1); 153 } 154 155 void 156 tmproutes_destroy(struct rib_head *rh) 157 { 158 159 callout_drain(&rh->expire_callout); 160 } 161