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 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 #include "opt_inet.h" 31 #include "opt_inet6.h" 32 #include "opt_route.h" 33 34 #include <sys/param.h> 35 #include <sys/jail.h> 36 #include <sys/systm.h> 37 #include <sys/malloc.h> 38 #include <sys/mbuf.h> 39 #include <sys/socket.h> 40 #include <sys/sysctl.h> 41 #include <sys/syslog.h> 42 #include <sys/sysproto.h> 43 #include <sys/proc.h> 44 #include <sys/domain.h> 45 #include <sys/kernel.h> 46 #include <sys/lock.h> 47 #include <sys/rmlock.h> 48 49 #include <net/if.h> 50 #include <net/if_var.h> 51 #include <net/if_dl.h> 52 #include <net/route.h> 53 #include <net/route/route_ctl.h> 54 #include <net/route/route_var.h> 55 #include <net/route/nhop_utils.h> 56 #include <net/route/nhop.h> 57 #include <net/route/nhop_var.h> 58 #ifdef INET 59 #include <netinet/in_fib.h> 60 #endif 61 #ifdef INET6 62 #include <netinet6/in6_fib.h> 63 #endif 64 #include <net/vnet.h> 65 66 /* 67 * RIB helper functions. 68 */ 69 70 void 71 rib_walk_ext_locked(struct rib_head *rnh, rib_walktree_f_t *wa_f, 72 rib_walk_hook_f_t *hook_f, void *arg) 73 { 74 if (hook_f != NULL) 75 hook_f(rnh, RIB_WALK_HOOK_PRE, arg); 76 rnh->rnh_walktree(&rnh->head, (walktree_f_t *)wa_f, arg); 77 if (hook_f != NULL) 78 hook_f(rnh, RIB_WALK_HOOK_POST, arg); 79 } 80 81 /* 82 * Calls @wa_f with @arg for each entry in the table specified by 83 * @af and @fibnum. 84 * 85 * @ss_t callback is called before and after the tree traversal 86 * while holding table lock. 87 * 88 * Table is traversed under read lock unless @wlock is set. 89 */ 90 void 91 rib_walk_ext_internal(struct rib_head *rnh, bool wlock, rib_walktree_f_t *wa_f, 92 rib_walk_hook_f_t *hook_f, void *arg) 93 { 94 RIB_RLOCK_TRACKER; 95 96 if (wlock) 97 RIB_WLOCK(rnh); 98 else 99 RIB_RLOCK(rnh); 100 rib_walk_ext_locked(rnh, wa_f, hook_f, arg); 101 if (wlock) 102 RIB_WUNLOCK(rnh); 103 else 104 RIB_RUNLOCK(rnh); 105 } 106 107 void 108 rib_walk_ext(uint32_t fibnum, int family, bool wlock, rib_walktree_f_t *wa_f, 109 rib_walk_hook_f_t *hook_f, void *arg) 110 { 111 struct rib_head *rnh; 112 113 if ((rnh = rt_tables_get_rnh(fibnum, family)) != NULL) 114 rib_walk_ext_internal(rnh, wlock, wa_f, hook_f, arg); 115 } 116 117 /* 118 * Calls @wa_f with @arg for each entry in the table specified by 119 * @af and @fibnum. 120 * 121 * Table is traversed under read lock unless @wlock is set. 122 */ 123 void 124 rib_walk(uint32_t fibnum, int family, bool wlock, rib_walktree_f_t *wa_f, 125 void *arg) 126 { 127 128 rib_walk_ext(fibnum, family, wlock, wa_f, NULL, arg); 129 } 130 131 /* 132 * Iterates over all existing fibs in system calling 133 * @hook_f function before/after traversing each fib. 134 * Calls @wa_f function for each element in current fib. 135 * If af is not AF_UNSPEC, iterates over fibs in particular 136 * address family. 137 */ 138 void 139 rib_foreach_table_walk(int family, bool wlock, rib_walktree_f_t *wa_f, 140 rib_walk_hook_f_t *hook_f, void *arg) 141 { 142 143 for (uint32_t fibnum = 0; fibnum < rt_numfibs; fibnum++) { 144 /* Do we want some specific family? */ 145 if (family != AF_UNSPEC) { 146 rib_walk_ext(fibnum, family, wlock, wa_f, hook_f, arg); 147 continue; 148 } 149 150 for (int i = 1; i <= AF_MAX; i++) 151 rib_walk_ext(fibnum, i, wlock, wa_f, hook_f, arg); 152 } 153 } 154 155 /* 156 * Iterates over all existing fibs in system and deletes each element 157 * for which @filter_f function returns non-zero value. 158 * If @family is not AF_UNSPEC, iterates over fibs in particular 159 * address family. 160 */ 161 void 162 rib_foreach_table_walk_del(int family, rib_filter_f_t *filter_f, void *arg) 163 { 164 165 for (uint32_t fibnum = 0; fibnum < rt_numfibs; fibnum++) { 166 /* Do we want some specific family? */ 167 if (family != AF_UNSPEC) { 168 rib_walk_del(fibnum, family, filter_f, arg, 0); 169 continue; 170 } 171 172 for (int i = 1; i <= AF_MAX; i++) 173 rib_walk_del(fibnum, i, filter_f, arg, 0); 174 } 175 } 176 177 178 /* 179 * Wrapper for the control plane functions for performing af-agnostic 180 * lookups. 181 * @fibnum: fib to perform the lookup. 182 * @dst: sockaddr with family and addr filled in. IPv6 addresses needs to be in 183 * deembedded from. 184 * @flags: fib(9) flags. 185 * @flowid: flow id for path selection in multipath use case. 186 * 187 * Returns nhop_object or NULL. 188 * 189 * Requires NET_EPOCH. 190 * 191 */ 192 struct nhop_object * 193 rib_lookup(uint32_t fibnum, const struct sockaddr *dst, uint32_t flags, 194 uint32_t flowid) 195 { 196 struct nhop_object *nh; 197 198 nh = NULL; 199 200 switch (dst->sa_family) { 201 #ifdef INET 202 case AF_INET: 203 { 204 const struct sockaddr_in *a = (const struct sockaddr_in *)dst; 205 nh = fib4_lookup(fibnum, a->sin_addr, 0, flags, flowid); 206 break; 207 } 208 #endif 209 #ifdef INET6 210 case AF_INET6: 211 { 212 const struct sockaddr_in6 *a = (const struct sockaddr_in6*)dst; 213 nh = fib6_lookup(fibnum, &a->sin6_addr, a->sin6_scope_id, 214 flags, flowid); 215 break; 216 } 217 #endif 218 } 219 220 return (nh); 221 } 222 223 #ifdef ROUTE_MPATH 224 static void 225 decompose_change_notification(struct rib_cmd_info *rc, route_notification_t *cb, 226 void *cbdata) 227 { 228 uint32_t num_old, num_new; 229 uint32_t nh_idx_old, nh_idx_new; 230 struct weightened_nhop *wn_old, *wn_new; 231 struct weightened_nhop tmp = { NULL, 0 }; 232 uint32_t idx_old = 0, idx_new = 0; 233 234 struct rib_cmd_info rc_del = { .rc_cmd = RTM_DELETE, .rc_rt = rc->rc_rt }; 235 struct rib_cmd_info rc_add = { .rc_cmd = RTM_ADD, .rc_rt = rc->rc_rt }; 236 237 if (NH_IS_NHGRP(rc->rc_nh_old)) { 238 wn_old = nhgrp_get_nhops((struct nhgrp_object *)rc->rc_nh_old, &num_old); 239 } else { 240 tmp.nh = rc->rc_nh_old; 241 tmp.weight = rc->rc_nh_weight; 242 wn_old = &tmp; 243 num_old = 1; 244 } 245 if (NH_IS_NHGRP(rc->rc_nh_new)) { 246 wn_new = nhgrp_get_nhops((struct nhgrp_object *)rc->rc_nh_new, &num_new); 247 } else { 248 tmp.nh = rc->rc_nh_new; 249 tmp.weight = rc->rc_nh_weight; 250 wn_new = &tmp; 251 num_new = 1; 252 } 253 254 /* Use the fact that each @wn array is sorted */ 255 /* 256 * Want to convert into set of add and delete operations 257 * [1] -> [1, 2] = A{2} 258 * [2] -> [1, 2] = A{1} 259 * [1, 2, 4]->[1, 3, 4] = A{2}, D{3} 260 * [1, 2, 4]->[1, 4] = D{2} 261 * [1, 2, 4] -> [3, 4] = D{1}, C{2,3} OR C{1,3}, D{2} OR D{1},D{2},A{3} 262 * [1, 2] -> [3, 4] = 263 * 264 */ 265 idx_old = 0; 266 while ((idx_old < num_old) && (idx_new < num_new)) { 267 nh_idx_old = wn_old[idx_old].nh->nh_priv->nh_idx; 268 nh_idx_new = wn_new[idx_new].nh->nh_priv->nh_idx; 269 270 if (nh_idx_old == nh_idx_new) { 271 if (wn_old[idx_old].weight != wn_new[idx_new].weight) { 272 /* Update weight by providing del/add notifications */ 273 rc_del.rc_nh_old = wn_old[idx_old].nh; 274 rc_del.rc_nh_weight = wn_old[idx_old].weight; 275 cb(&rc_del, cbdata); 276 277 rc_add.rc_nh_new = wn_new[idx_new].nh; 278 rc_add.rc_nh_weight = wn_new[idx_new].weight; 279 cb(&rc_add, cbdata); 280 } 281 idx_old++; 282 idx_new++; 283 } else if (nh_idx_old < nh_idx_new) { 284 /* 285 * [1, ~2~, 4], [1, ~3~, 4] 286 * [1, ~2~, 5], [1, ~3~, 4] 287 * [1, ~2~], [1, ~3~, 4] 288 */ 289 if ((idx_old + 1 >= num_old) || 290 (wn_old[idx_old + 1].nh->nh_priv->nh_idx > nh_idx_new)) { 291 /* Add new unless the next old item is still <= new */ 292 rc_add.rc_nh_new = wn_new[idx_new].nh; 293 rc_add.rc_nh_weight = wn_new[idx_new].weight; 294 cb(&rc_add, cbdata); 295 idx_new++; 296 } 297 /* In any case, delete current old */ 298 rc_del.rc_nh_old = wn_old[idx_old].nh; 299 rc_del.rc_nh_weight = wn_old[idx_old].weight; 300 cb(&rc_del, cbdata); 301 idx_old++; 302 } else { 303 /* 304 * nh_idx_old > nh_idx_new 305 * 306 * [1, ~3~, 4], [1, ~2~, 4] 307 * [1, ~3~, 5], [1, ~2~, 4] 308 * [1, ~3~, 4], [1, ~2~] 309 */ 310 if ((idx_new + 1 >= num_new) || 311 (wn_new[idx_new + 1].nh->nh_priv->nh_idx > nh_idx_old)) { 312 /* No next item or next item is > current one */ 313 rc_add.rc_nh_new = wn_new[idx_new].nh; 314 rc_add.rc_nh_weight = wn_new[idx_new].weight; 315 cb(&rc_add, cbdata); 316 idx_new++; 317 } 318 /* In any case, delete current old */ 319 rc_del.rc_nh_old = wn_old[idx_old].nh; 320 rc_del.rc_nh_weight = wn_old[idx_old].weight; 321 cb(&rc_del, cbdata); 322 idx_old++; 323 } 324 } 325 326 while (idx_old < num_old) { 327 rc_del.rc_nh_old = wn_old[idx_old].nh; 328 rc_del.rc_nh_weight = wn_old[idx_old].weight; 329 cb(&rc_del, cbdata); 330 idx_old++; 331 } 332 333 while (idx_new < num_new) { 334 rc_add.rc_nh_new = wn_new[idx_new].nh; 335 rc_add.rc_nh_weight = wn_new[idx_new].weight; 336 cb(&rc_add, cbdata); 337 idx_new++; 338 } 339 } 340 341 /* 342 * Decompose multipath cmd info @rc into a list of add/del/change 343 * single-path operations, calling @cb callback for each operation. 344 * Assumes at least one of the nexthops in @rc is multipath. 345 */ 346 void 347 rib_decompose_notification(struct rib_cmd_info *rc, route_notification_t *cb, 348 void *cbdata) 349 { 350 struct weightened_nhop *wn; 351 uint32_t num_nhops; 352 struct rib_cmd_info rc_new; 353 354 rc_new = *rc; 355 DPRINTF("cb=%p cmd=%d nh_old=%p nh_new=%p", 356 cb, rc->cmd, rc->nh_old, rc->nh_new); 357 switch (rc->rc_cmd) { 358 case RTM_ADD: 359 if (!NH_IS_NHGRP(rc->rc_nh_new)) 360 return; 361 wn = nhgrp_get_nhops((struct nhgrp_object *)rc->rc_nh_new, &num_nhops); 362 for (uint32_t i = 0; i < num_nhops; i++) { 363 rc_new.rc_nh_new = wn[i].nh; 364 rc_new.rc_nh_weight = wn[i].weight; 365 cb(&rc_new, cbdata); 366 } 367 break; 368 case RTM_DELETE: 369 if (!NH_IS_NHGRP(rc->rc_nh_old)) 370 return; 371 wn = nhgrp_get_nhops((struct nhgrp_object *)rc->rc_nh_old, &num_nhops); 372 for (uint32_t i = 0; i < num_nhops; i++) { 373 rc_new.rc_nh_old = wn[i].nh; 374 rc_new.rc_nh_weight = wn[i].weight; 375 cb(&rc_new, cbdata); 376 } 377 break; 378 case RTM_CHANGE: 379 if (!NH_IS_NHGRP(rc->rc_nh_old) && !NH_IS_NHGRP(rc->rc_nh_new)) 380 return; 381 decompose_change_notification(rc, cb, cbdata); 382 break; 383 } 384 } 385 #endif 386