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 * Note: In this file a 'fib' is a "forwarding information base" * 33 * Which is the new name for an in kernel routing (next hop) table. * 34 ***********************************************************************/ 35 36 #include <sys/cdefs.h> 37 #include "opt_route.h" 38 39 #include <sys/param.h> 40 #include <sys/socket.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/jail.h> 44 #include <sys/osd.h> 45 #include <sys/proc.h> 46 #include <sys/sysctl.h> 47 #include <sys/syslog.h> 48 #include <sys/kernel.h> 49 #include <sys/lock.h> 50 #include <sys/sx.h> 51 #include <sys/domain.h> 52 #include <sys/sysproto.h> 53 54 #include <net/vnet.h> 55 #include <net/route.h> 56 #include <net/route/route_ctl.h> 57 #include <net/route/route_var.h> 58 59 /* Kernel config default option. */ 60 #ifdef ROUTETABLES 61 #if ROUTETABLES <= 0 62 #error "ROUTETABLES defined too low" 63 #endif 64 #if ROUTETABLES > RT_MAXFIBS 65 #error "ROUTETABLES defined too big" 66 #endif 67 #define RT_NUMFIBS ROUTETABLES 68 #endif /* ROUTETABLES */ 69 /* Initialize to default if not otherwise set. */ 70 #ifndef RT_NUMFIBS 71 #define RT_NUMFIBS 1 72 #endif 73 74 static void grow_rtables(uint32_t num_fibs); 75 76 VNET_DEFINE_STATIC(struct sx, rtables_lock); 77 #define V_rtables_lock VNET(rtables_lock) 78 #define RTABLES_LOCK() sx_xlock(&V_rtables_lock) 79 #define RTABLES_UNLOCK() sx_xunlock(&V_rtables_lock) 80 #define RTABLES_LOCK_INIT() sx_init(&V_rtables_lock, "rtables lock") 81 #define RTABLES_LOCK_ASSERT() sx_assert(&V_rtables_lock, SA_LOCKED) 82 83 VNET_DEFINE_STATIC(struct rib_head **, rt_tables); 84 #define V_rt_tables VNET(rt_tables) 85 86 VNET_DEFINE(uint32_t, _rt_numfibs) = RT_NUMFIBS; 87 88 /* 89 * Handler for net.my_fibnum. 90 * Returns current fib of the process. 91 */ 92 static int 93 sysctl_my_fibnum(SYSCTL_HANDLER_ARGS) 94 { 95 int fibnum; 96 int error; 97 98 fibnum = curthread->td_proc->p_fibnum; 99 error = sysctl_handle_int(oidp, &fibnum, 0, req); 100 return (error); 101 } 102 SYSCTL_PROC(_net, OID_AUTO, my_fibnum, 103 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 104 &sysctl_my_fibnum, "I", 105 "default FIB of caller"); 106 107 static uint32_t 108 normalize_num_rtables(uint32_t num_rtables) 109 { 110 111 if (num_rtables > RT_MAXFIBS) 112 num_rtables = RT_MAXFIBS; 113 else if (num_rtables == 0) 114 num_rtables = 1; 115 return (num_rtables); 116 } 117 118 /* 119 * Sets the number of fibs in the current vnet. 120 * Function does not allow shrinking number of rtables. 121 */ 122 static int 123 sysctl_fibs(SYSCTL_HANDLER_ARGS) 124 { 125 uint32_t new_fibs; 126 int error; 127 128 RTABLES_LOCK(); 129 new_fibs = V_rt_numfibs; 130 error = sysctl_handle_32(oidp, &new_fibs, 0, req); 131 if (error == 0) { 132 new_fibs = normalize_num_rtables(new_fibs); 133 134 if (new_fibs < V_rt_numfibs) 135 error = ENOTCAPABLE; 136 if (new_fibs > V_rt_numfibs) 137 grow_rtables(new_fibs); 138 } 139 RTABLES_UNLOCK(); 140 141 return (error); 142 } 143 SYSCTL_PROC(_net, OID_AUTO, fibs, 144 CTLFLAG_VNET | CTLTYPE_U32 | CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_MPSAFE, 145 NULL, 0, &sysctl_fibs, "IU", 146 "set number of fibs"); 147 148 /* 149 * Sets fib of a current process. 150 */ 151 int 152 sys_setfib(struct thread *td, struct setfib_args *uap) 153 { 154 int error = 0; 155 156 CURVNET_SET(TD_TO_VNET(td)); 157 if (uap->fibnum >= 0 && uap->fibnum < V_rt_numfibs) 158 td->td_proc->p_fibnum = uap->fibnum; 159 else 160 error = EINVAL; 161 CURVNET_RESTORE(); 162 163 return (error); 164 } 165 166 static int 167 rtables_check_proc_fib(void *obj, void *data) 168 { 169 struct prison *pr = obj; 170 struct thread *td = data; 171 int error = 0; 172 173 if (TD_TO_VNET(td) != pr->pr_vnet) { 174 /* number of fibs may be lower in a new vnet */ 175 CURVNET_SET(pr->pr_vnet); 176 if (td->td_proc->p_fibnum >= V_rt_numfibs) 177 error = EINVAL; 178 CURVNET_RESTORE(); 179 } 180 return (error); 181 } 182 183 static void 184 rtables_prison_destructor(void *data) 185 { 186 } 187 188 static void 189 rtables_init(void) 190 { 191 osd_method_t methods[PR_MAXMETHOD] = { 192 [PR_METHOD_ATTACH] = rtables_check_proc_fib, 193 }; 194 osd_jail_register(rtables_prison_destructor, methods); 195 } 196 SYSINIT(rtables_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, rtables_init, NULL); 197 198 199 /* 200 * If required, copy interface routes from existing tables to the 201 * newly-created routing table. 202 */ 203 static void 204 populate_kernel_routes(struct rib_head **new_rt_tables, struct rib_head *rh) 205 { 206 for (int i = 0; i < V_rt_numfibs; i++) { 207 struct rib_head *rh_src = new_rt_tables[i * (AF_MAX + 1) + rh->rib_family]; 208 if ((rh_src != NULL) && (rh_src != rh)) 209 rib_copy_kernel_routes(rh_src, rh); 210 } 211 } 212 213 /* 214 * Grows up the number of routing tables in the current fib. 215 * Function creates new index array for all rtables and allocates 216 * remaining routing tables. 217 */ 218 static void 219 grow_rtables(uint32_t num_tables) 220 { 221 struct domain *dom; 222 struct rib_head **prnh, *rh; 223 struct rib_head **new_rt_tables, **old_rt_tables; 224 int family; 225 226 RTABLES_LOCK_ASSERT(); 227 228 KASSERT(num_tables >= V_rt_numfibs, ("num_tables(%u) < rt_numfibs(%u)\n", 229 num_tables, V_rt_numfibs)); 230 231 new_rt_tables = mallocarray(num_tables * (AF_MAX + 1), sizeof(void *), 232 M_RTABLE, M_WAITOK | M_ZERO); 233 234 #ifdef FIB_ALGO 235 fib_grow_rtables(num_tables); 236 #endif 237 238 /* 239 * Current rt_tables layout: 240 * fib0[af0, af1, af2, .., AF_MAX]fib1[af0, af1, af2, .., Af_MAX].. 241 * this allows to copy existing tables data by using memcpy() 242 */ 243 if (V_rt_tables != NULL) 244 memcpy(new_rt_tables, V_rt_tables, 245 V_rt_numfibs * (AF_MAX + 1) * sizeof(void *)); 246 247 /* Populate the remainders */ 248 SLIST_FOREACH(dom, &domains, dom_next) { 249 if (dom->dom_rtattach == NULL) 250 continue; 251 family = dom->dom_family; 252 for (int i = 0; i < num_tables; i++) { 253 prnh = &new_rt_tables[i * (AF_MAX + 1) + family]; 254 if (*prnh != NULL) 255 continue; 256 rh = dom->dom_rtattach(i); 257 if (rh == NULL) 258 log(LOG_ERR, "unable to create routing table for %d.%d\n", 259 dom->dom_family, i); 260 else 261 populate_kernel_routes(new_rt_tables, rh); 262 *prnh = rh; 263 } 264 } 265 266 /* 267 * Update rtables pointer. 268 * Ensure all writes to new_rt_tables has been completed before 269 * switching pointer. 270 */ 271 atomic_thread_fence_rel(); 272 old_rt_tables = V_rt_tables; 273 V_rt_tables = new_rt_tables; 274 275 /* Wait till all cpus see new pointers */ 276 atomic_thread_fence_rel(); 277 NET_EPOCH_WAIT(); 278 279 /* Set number of fibs to a new value */ 280 V_rt_numfibs = num_tables; 281 282 #ifdef FIB_ALGO 283 /* Attach fib algo to the new rtables */ 284 SLIST_FOREACH(dom, &domains, dom_next) { 285 if (dom->dom_rtattach != NULL) 286 fib_setup_family(dom->dom_family, num_tables); 287 } 288 #endif 289 290 if (old_rt_tables != NULL) 291 free(old_rt_tables, M_RTABLE); 292 } 293 294 static void 295 vnet_rtables_init(const void *unused __unused) 296 { 297 int num_rtables_base; 298 299 if (IS_DEFAULT_VNET(curvnet)) { 300 num_rtables_base = RT_NUMFIBS; 301 TUNABLE_INT_FETCH("net.fibs", &num_rtables_base); 302 V_rt_numfibs = normalize_num_rtables(num_rtables_base); 303 } else 304 V_rt_numfibs = 1; 305 306 vnet_rtzone_init(); 307 #ifdef FIB_ALGO 308 vnet_fib_init(); 309 #endif 310 RTABLES_LOCK_INIT(); 311 312 RTABLES_LOCK(); 313 grow_rtables(V_rt_numfibs); 314 RTABLES_UNLOCK(); 315 } 316 VNET_SYSINIT(vnet_rtables_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, 317 vnet_rtables_init, NULL); 318 319 #ifdef VIMAGE 320 static void 321 rtables_destroy(const void *unused __unused) 322 { 323 struct rib_head *rnh; 324 struct domain *dom; 325 int family; 326 327 RTABLES_LOCK(); 328 SLIST_FOREACH(dom, &domains, dom_next) { 329 if (dom->dom_rtdetach == NULL) 330 continue; 331 family = dom->dom_family; 332 for (int i = 0; i < V_rt_numfibs; i++) { 333 rnh = rt_tables_get_rnh(i, family); 334 dom->dom_rtdetach(rnh); 335 } 336 } 337 RTABLES_UNLOCK(); 338 339 /* 340 * dom_rtdetach calls rt_table_destroy(), which 341 * schedules deletion for all rtentries, nexthops and control 342 * structures. Wait for the destruction callbacks to fire. 343 * Note that this should result in freeing all rtentries, but 344 * nexthops deletions will be scheduled for the next epoch run 345 * and will be completed after vnet teardown. 346 */ 347 NET_EPOCH_DRAIN_CALLBACKS(); 348 349 free(V_rt_tables, M_RTABLE); 350 vnet_rtzone_destroy(); 351 #ifdef FIB_ALGO 352 vnet_fib_destroy(); 353 #endif 354 } 355 VNET_SYSUNINIT(rtables_destroy, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, 356 rtables_destroy, NULL); 357 #endif 358 359 static inline struct rib_head * 360 rt_tables_get_rnh_ptr(uint32_t table, sa_family_t family) 361 { 362 struct rib_head **prnh; 363 364 KASSERT(table < V_rt_numfibs, 365 ("%s: table out of bounds (%d < %d)", __func__, table, 366 V_rt_numfibs)); 367 KASSERT(family < (AF_MAX + 1), 368 ("%s: fam out of bounds (%d < %d)", __func__, family, AF_MAX + 1)); 369 370 /* rnh is [fib=0][af=0]. */ 371 prnh = V_rt_tables; 372 /* Get the offset to the requested table and fam. */ 373 prnh += table * (AF_MAX + 1) + family; 374 375 return (*prnh); 376 } 377 378 struct rib_head * 379 rt_tables_get_rnh(uint32_t table, sa_family_t family) 380 { 381 382 return (rt_tables_get_rnh_ptr(table, family)); 383 } 384 385 struct rib_head * 386 rt_tables_get_rnh_safe(uint32_t table, sa_family_t family) 387 { 388 if (__predict_false(table >= V_rt_numfibs)) 389 return (NULL); 390 if (__predict_false(family >= (AF_MAX + 1))) 391 return (NULL); 392 return (rt_tables_get_rnh_ptr(table, family)); 393 } 394 395 u_int 396 rt_tables_get_gen(uint32_t table, sa_family_t family) 397 { 398 struct rib_head *rnh; 399 400 rnh = rt_tables_get_rnh_ptr(table, family); 401 KASSERT(rnh != NULL, ("%s: NULL rib_head pointer table %d family %d", 402 __func__, table, family)); 403 return (rnh->rnh_gen); 404 } 405