1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (C) 2000 WIDE Project. 5 * 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 project 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 PROJECT 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 PROJECT 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 * $KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $ 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/malloc.h> 39 #include <sys/mbuf.h> 40 #include <sys/socket.h> 41 #include <sys/sockio.h> 42 #include <sys/systm.h> 43 #include <sys/queue.h> 44 #include <sys/sysctl.h> 45 #include <sys/syslog.h> 46 47 #include <net/if.h> 48 #include <net/if_var.h> 49 #include <net/vnet.h> 50 51 #include <netinet/in.h> 52 53 #include <netinet/ip6.h> 54 #include <netinet6/in6_var.h> 55 #include <netinet6/ip6_var.h> 56 #include <netinet6/scope6_var.h> 57 58 #ifdef ENABLE_DEFAULT_SCOPE 59 VNET_DEFINE(int, ip6_use_defzone) = 1; 60 #else 61 VNET_DEFINE(int, ip6_use_defzone) = 0; 62 #endif 63 VNET_DEFINE(int, deembed_scopeid) = 1; 64 SYSCTL_DECL(_net_inet6_ip6); 65 SYSCTL_INT(_net_inet6_ip6, OID_AUTO, deembed_scopeid, CTLFLAG_VNET | CTLFLAG_RW, 66 &VNET_NAME(deembed_scopeid), 0, 67 "Extract embedded zone ID and set it to sin6_scope_id in sockaddr_in6."); 68 69 /* 70 * The scope6_lock protects the global sid default stored in 71 * sid_default below. 72 */ 73 static struct mtx scope6_lock; 74 #define SCOPE6_LOCK_INIT() mtx_init(&scope6_lock, "scope6_lock", NULL, MTX_DEF) 75 #define SCOPE6_LOCK() mtx_lock(&scope6_lock) 76 #define SCOPE6_UNLOCK() mtx_unlock(&scope6_lock) 77 #define SCOPE6_LOCK_ASSERT() mtx_assert(&scope6_lock, MA_OWNED) 78 79 VNET_DEFINE_STATIC(struct scope6_id, sid_default); 80 #define V_sid_default VNET(sid_default) 81 82 #define SID(ifp) \ 83 (((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id) 84 85 static int scope6_get(struct ifnet *, struct scope6_id *); 86 static int scope6_set(struct ifnet *, struct scope6_id *); 87 88 void 89 scope6_init(void) 90 { 91 92 bzero(&V_sid_default, sizeof(V_sid_default)); 93 94 if (!IS_DEFAULT_VNET(curvnet)) 95 return; 96 97 SCOPE6_LOCK_INIT(); 98 } 99 100 struct scope6_id * 101 scope6_ifattach(struct ifnet *ifp) 102 { 103 struct scope6_id *sid; 104 105 sid = malloc(sizeof(*sid), M_IFADDR, M_WAITOK | M_ZERO); 106 /* 107 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. 108 * Should we rather hardcode here? 109 */ 110 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; 111 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; 112 return (sid); 113 } 114 115 void 116 scope6_ifdetach(struct scope6_id *sid) 117 { 118 119 free(sid, M_IFADDR); 120 } 121 122 int 123 scope6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp) 124 { 125 struct in6_ifreq *ifr; 126 127 if (ifp->if_afdata[AF_INET6] == NULL) 128 return (EPFNOSUPPORT); 129 130 ifr = (struct in6_ifreq *)data; 131 switch (cmd) { 132 case SIOCSSCOPE6: 133 return (scope6_set(ifp, 134 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 135 case SIOCGSCOPE6: 136 return (scope6_get(ifp, 137 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 138 case SIOCGSCOPE6DEF: 139 return (scope6_get_default( 140 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 141 default: 142 return (EOPNOTSUPP); 143 } 144 } 145 146 static int 147 scope6_set(struct ifnet *ifp, struct scope6_id *idlist) 148 { 149 int i; 150 int error = 0; 151 struct scope6_id *sid = NULL; 152 153 IF_AFDATA_WLOCK(ifp); 154 sid = SID(ifp); 155 156 if (!sid) { /* paranoid? */ 157 IF_AFDATA_WUNLOCK(ifp); 158 return (EINVAL); 159 } 160 161 /* 162 * XXX: We need more consistency checks of the relationship among 163 * scopes (e.g. an organization should be larger than a site). 164 */ 165 166 /* 167 * TODO(XXX): after setting, we should reflect the changes to 168 * interface addresses, routing table entries, PCB entries... 169 */ 170 171 for (i = 0; i < 16; i++) { 172 if (idlist->s6id_list[i] && 173 idlist->s6id_list[i] != sid->s6id_list[i]) { 174 /* 175 * An interface zone ID must be the corresponding 176 * interface index by definition. 177 */ 178 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL && 179 idlist->s6id_list[i] != ifp->if_index) { 180 IF_AFDATA_WUNLOCK(ifp); 181 return (EINVAL); 182 } 183 184 if (i == IPV6_ADDR_SCOPE_LINKLOCAL && 185 idlist->s6id_list[i] > V_if_index) { 186 /* 187 * XXX: theoretically, there should be no 188 * relationship between link IDs and interface 189 * IDs, but we check the consistency for 190 * safety in later use. 191 */ 192 IF_AFDATA_WUNLOCK(ifp); 193 return (EINVAL); 194 } 195 196 /* 197 * XXX: we must need lots of work in this case, 198 * but we simply set the new value in this initial 199 * implementation. 200 */ 201 sid->s6id_list[i] = idlist->s6id_list[i]; 202 } 203 } 204 IF_AFDATA_WUNLOCK(ifp); 205 206 return (error); 207 } 208 209 static int 210 scope6_get(struct ifnet *ifp, struct scope6_id *idlist) 211 { 212 struct epoch_tracker et; 213 struct scope6_id *sid; 214 215 /* We only need to lock the interface's afdata for SID() to work. */ 216 NET_EPOCH_ENTER(et); 217 sid = SID(ifp); 218 if (sid == NULL) { /* paranoid? */ 219 NET_EPOCH_EXIT(et); 220 return (EINVAL); 221 } 222 223 *idlist = *sid; 224 225 NET_EPOCH_EXIT(et); 226 return (0); 227 } 228 229 /* 230 * Get a scope of the address. Node-local, link-local, site-local or global. 231 */ 232 int 233 in6_addrscope(const struct in6_addr *addr) 234 { 235 236 if (IN6_IS_ADDR_MULTICAST(addr)) { 237 /* 238 * Addresses with reserved value F must be treated as 239 * global multicast addresses. 240 */ 241 if (IPV6_ADDR_MC_SCOPE(addr) == 0x0f) 242 return (IPV6_ADDR_SCOPE_GLOBAL); 243 return (IPV6_ADDR_MC_SCOPE(addr)); 244 } 245 if (IN6_IS_ADDR_LINKLOCAL(addr) || 246 IN6_IS_ADDR_LOOPBACK(addr)) 247 return (IPV6_ADDR_SCOPE_LINKLOCAL); 248 if (IN6_IS_ADDR_SITELOCAL(addr)) 249 return (IPV6_ADDR_SCOPE_SITELOCAL); 250 return (IPV6_ADDR_SCOPE_GLOBAL); 251 } 252 253 /* 254 * ifp - note that this might be NULL 255 */ 256 257 void 258 scope6_setdefault(struct ifnet *ifp) 259 { 260 261 /* 262 * Currently, this function just sets the default "interfaces" 263 * and "links" according to the given interface. 264 * We might eventually have to separate the notion of "link" from 265 * "interface" and provide a user interface to set the default. 266 */ 267 SCOPE6_LOCK(); 268 if (ifp) { 269 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 270 ifp->if_index; 271 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 272 ifp->if_index; 273 } else { 274 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; 275 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; 276 } 277 SCOPE6_UNLOCK(); 278 } 279 280 int 281 scope6_get_default(struct scope6_id *idlist) 282 { 283 284 SCOPE6_LOCK(); 285 *idlist = V_sid_default; 286 SCOPE6_UNLOCK(); 287 288 return (0); 289 } 290 291 u_int32_t 292 scope6_addr2default(struct in6_addr *addr) 293 { 294 u_int32_t id; 295 296 /* 297 * special case: The loopback address should be considered as 298 * link-local, but there's no ambiguity in the syntax. 299 */ 300 if (IN6_IS_ADDR_LOOPBACK(addr)) 301 return (0); 302 303 /* 304 * XXX: 32-bit read is atomic on all our platforms, is it OK 305 * not to lock here? 306 */ 307 SCOPE6_LOCK(); 308 id = V_sid_default.s6id_list[in6_addrscope(addr)]; 309 SCOPE6_UNLOCK(); 310 return (id); 311 } 312 313 /* 314 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID 315 * is unspecified (=0), needs to be specified, and the default zone ID can be 316 * used, the default value will be used. 317 * This routine then generates the kernel-internal form: if the address scope 318 * of is interface-local or link-local, embed the interface index in the 319 * address. 320 */ 321 int 322 sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) 323 { 324 u_int32_t zoneid; 325 326 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) 327 zoneid = scope6_addr2default(&sin6->sin6_addr); 328 329 if (zoneid != 0 && 330 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 331 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { 332 /* 333 * At this moment, we only check interface-local and 334 * link-local scope IDs, and use interface indices as the 335 * zone IDs assuming a one-to-one mapping between interfaces 336 * and links. 337 */ 338 if (V_if_index < zoneid || ifnet_byindex(zoneid) == NULL) 339 return (ENXIO); 340 341 /* XXX assignment to 16bit from 32bit variable */ 342 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 343 sin6->sin6_scope_id = 0; 344 } 345 346 return 0; 347 } 348 349 /* 350 * generate standard sockaddr_in6 from embedded form. 351 */ 352 int 353 sa6_recoverscope(struct sockaddr_in6 *sin6) 354 { 355 char ip6buf[INET6_ADDRSTRLEN]; 356 u_int32_t zoneid; 357 358 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 359 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { 360 /* 361 * KAME assumption: link id == interface id 362 */ 363 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 364 if (zoneid) { 365 /* sanity check */ 366 if (V_if_index < zoneid) 367 return (ENXIO); 368 #if 0 369 /* XXX: Disabled due to possible deadlock. */ 370 if (!ifnet_byindex(zoneid)) 371 return (ENXIO); 372 #endif 373 if (sin6->sin6_scope_id != 0 && 374 zoneid != sin6->sin6_scope_id) { 375 log(LOG_NOTICE, 376 "%s: embedded scope mismatch: %s%%%d. " 377 "sin6_scope_id was overridden\n", __func__, 378 ip6_sprintf(ip6buf, &sin6->sin6_addr), 379 sin6->sin6_scope_id); 380 } 381 sin6->sin6_addr.s6_addr16[1] = 0; 382 sin6->sin6_scope_id = zoneid; 383 } 384 } 385 386 return 0; 387 } 388 389 /* 390 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is 391 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded 392 * in the in6_addr structure, in6 will be modified. 393 * 394 * ret_id - unnecessary? 395 */ 396 int 397 in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id) 398 { 399 int scope; 400 u_int32_t zoneid = 0; 401 struct scope6_id *sid; 402 403 /* 404 * special case: the loopback address can only belong to a loopback 405 * interface. 406 */ 407 if (IN6_IS_ADDR_LOOPBACK(in6)) { 408 if (!(ifp->if_flags & IFF_LOOPBACK)) 409 return (EINVAL); 410 } else { 411 scope = in6_addrscope(in6); 412 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL || 413 scope == IPV6_ADDR_SCOPE_LINKLOCAL) { 414 /* 415 * Currently we use interface indices as the 416 * zone IDs for interface-local and link-local 417 * scopes. 418 */ 419 zoneid = ifp->if_index; 420 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 421 } else if (scope != IPV6_ADDR_SCOPE_GLOBAL) { 422 struct epoch_tracker et; 423 424 NET_EPOCH_ENTER(et); 425 sid = SID(ifp); 426 zoneid = sid->s6id_list[scope]; 427 NET_EPOCH_EXIT(et); 428 } 429 } 430 431 if (ret_id != NULL) 432 *ret_id = zoneid; 433 434 return (0); 435 } 436 437 /* 438 * Just clear the embedded scope identifier. Return 0 if the original address 439 * is intact; return non 0 if the address is modified. 440 */ 441 int 442 in6_clearscope(struct in6_addr *in6) 443 { 444 int modified = 0; 445 446 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 447 if (in6->s6_addr16[1] != 0) 448 modified = 1; 449 in6->s6_addr16[1] = 0; 450 } 451 452 return (modified); 453 } 454 455 /* 456 * Return the scope identifier or zero. 457 */ 458 uint16_t 459 in6_getscope(const struct in6_addr *in6) 460 { 461 462 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) 463 return (in6->s6_addr16[1]); 464 465 return (0); 466 } 467 468 /* 469 * Return pointer to ifnet structure, corresponding to the zone id of 470 * link-local scope. 471 */ 472 struct ifnet* 473 in6_getlinkifnet(uint32_t zoneid) 474 { 475 476 return (ifnet_byindex((u_short)zoneid)); 477 } 478 479 /* 480 * Return zone id for the specified scope. 481 */ 482 uint32_t 483 in6_getscopezone(const struct ifnet *ifp, int scope) 484 { 485 486 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL || 487 scope == IPV6_ADDR_SCOPE_LINKLOCAL) 488 return (ifp->if_index); 489 if (scope >= 0 && scope < IPV6_ADDR_SCOPES_COUNT) 490 return (SID(ifp)->s6id_list[scope]); 491 return (0); 492 } 493 494 /* 495 * Extracts scope from adddress @dst, stores cleared address 496 * inside @dst and zone inside @scopeid 497 */ 498 void 499 in6_splitscope(const struct in6_addr *src, struct in6_addr *dst, 500 uint32_t *scopeid) 501 { 502 uint32_t zoneid; 503 504 *dst = *src; 505 zoneid = ntohs(in6_getscope(dst)); 506 in6_clearscope(dst); 507 *scopeid = zoneid; 508 } 509 510 /* 511 * This function is for checking sockaddr_in6 structure passed 512 * from the application level (usually). 513 * 514 * sin6_scope_id should be set for link-local unicast, link-local and 515 * interface-local multicast addresses. 516 * 517 * If it is zero, then look into default zone ids. If default zone id is 518 * not set or disabled, then return error. 519 */ 520 int 521 sa6_checkzone(struct sockaddr_in6 *sa6) 522 { 523 int scope; 524 525 scope = in6_addrscope(&sa6->sin6_addr); 526 if (scope == IPV6_ADDR_SCOPE_GLOBAL) 527 return (sa6->sin6_scope_id ? EINVAL: 0); 528 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr) && 529 scope != IPV6_ADDR_SCOPE_LINKLOCAL && 530 scope != IPV6_ADDR_SCOPE_INTFACELOCAL) { 531 if (sa6->sin6_scope_id == 0 && V_ip6_use_defzone != 0) 532 sa6->sin6_scope_id = V_sid_default.s6id_list[scope]; 533 return (0); 534 } 535 /* 536 * Since ::1 address always configured on the lo0, we can 537 * automatically set its zone id, when it is not specified. 538 * Return error, when specified zone id doesn't match with 539 * actual value. 540 */ 541 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) { 542 if (sa6->sin6_scope_id == 0) 543 sa6->sin6_scope_id = in6_getscopezone(V_loif, scope); 544 else if (sa6->sin6_scope_id != in6_getscopezone(V_loif, scope)) 545 return (EADDRNOTAVAIL); 546 } 547 /* XXX: we can validate sin6_scope_id here */ 548 if (sa6->sin6_scope_id != 0) 549 return (0); 550 if (V_ip6_use_defzone != 0) 551 sa6->sin6_scope_id = V_sid_default.s6id_list[scope]; 552 /* Return error if we can't determine zone id */ 553 return (sa6->sin6_scope_id ? 0: EADDRNOTAVAIL); 554 } 555 556 /* 557 * This function is similar to sa6_checkzone, but it uses given ifp 558 * to initialize sin6_scope_id. 559 */ 560 int 561 sa6_checkzone_ifp(struct ifnet *ifp, struct sockaddr_in6 *sa6) 562 { 563 int scope; 564 565 scope = in6_addrscope(&sa6->sin6_addr); 566 if (scope == IPV6_ADDR_SCOPE_LINKLOCAL || 567 scope == IPV6_ADDR_SCOPE_INTFACELOCAL) { 568 if (sa6->sin6_scope_id == 0) { 569 sa6->sin6_scope_id = in6_getscopezone(ifp, scope); 570 return (0); 571 } else if (sa6->sin6_scope_id != in6_getscopezone(ifp, scope)) 572 return (EADDRNOTAVAIL); 573 } 574 return (sa6_checkzone(sa6)); 575 } 576 577 578