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/param.h> 35 #include <sys/malloc.h> 36 #include <sys/mbuf.h> 37 #include <sys/socket.h> 38 #include <sys/sockio.h> 39 #include <sys/systm.h> 40 #include <sys/queue.h> 41 #include <sys/sysctl.h> 42 #include <sys/syslog.h> 43 44 #include <net/if.h> 45 #include <net/if_var.h> 46 #include <net/if_private.h> 47 #include <net/vnet.h> 48 49 #include <netinet/in.h> 50 51 #include <netinet/ip6.h> 52 #include <netinet6/in6_var.h> 53 #include <netinet6/ip6_var.h> 54 #include <netinet6/scope6_var.h> 55 56 #ifdef ENABLE_DEFAULT_SCOPE 57 VNET_DEFINE(int, ip6_use_defzone) = 1; 58 #else 59 VNET_DEFINE(int, ip6_use_defzone) = 0; 60 #endif 61 SYSCTL_DECL(_net_inet6_ip6); 62 63 /* 64 * The scope6_lock protects the global sid default stored in 65 * sid_default below. 66 */ 67 static struct mtx scope6_lock; 68 #define SCOPE6_LOCK_INIT() mtx_init(&scope6_lock, "scope6_lock", NULL, MTX_DEF) 69 #define SCOPE6_LOCK() mtx_lock(&scope6_lock) 70 #define SCOPE6_UNLOCK() mtx_unlock(&scope6_lock) 71 #define SCOPE6_LOCK_ASSERT() mtx_assert(&scope6_lock, MA_OWNED) 72 73 VNET_DEFINE_STATIC(struct scope6_id, sid_default); 74 #define V_sid_default VNET(sid_default) 75 76 #define SID(ifp) ((ifp)->if_inet6->scope6_id) 77 78 static int scope6_get(struct ifnet *, struct scope6_id *); 79 static int scope6_set(struct ifnet *, struct scope6_id *); 80 81 void 82 scope6_init(void) 83 { 84 85 bzero(&V_sid_default, sizeof(V_sid_default)); 86 87 if (!IS_DEFAULT_VNET(curvnet)) 88 return; 89 90 SCOPE6_LOCK_INIT(); 91 } 92 93 struct scope6_id * 94 scope6_ifattach(struct ifnet *ifp) 95 { 96 struct scope6_id *sid; 97 98 sid = malloc(sizeof(*sid), M_IFADDR, M_WAITOK | M_ZERO); 99 /* 100 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. 101 * Should we rather hardcode here? 102 */ 103 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; 104 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; 105 return (sid); 106 } 107 108 void 109 scope6_ifdetach(struct scope6_id *sid) 110 { 111 112 free(sid, M_IFADDR); 113 } 114 115 int 116 scope6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp) 117 { 118 struct in6_ifreq *ifr; 119 120 if (ifp->if_inet6 == NULL) 121 return (EPFNOSUPPORT); 122 123 ifr = (struct in6_ifreq *)data; 124 switch (cmd) { 125 case SIOCSSCOPE6: 126 return (scope6_set(ifp, 127 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 128 case SIOCGSCOPE6: 129 return (scope6_get(ifp, 130 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 131 case SIOCGSCOPE6DEF: 132 return (scope6_get_default( 133 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 134 default: 135 return (EOPNOTSUPP); 136 } 137 } 138 139 /* 140 * XXXGL: The use of IF_ADDR_WLOCK (previously it was IF_AFDATA_LOCK) in this 141 * function is quite strange. 142 */ 143 static int 144 scope6_set(struct ifnet *ifp, struct scope6_id *idlist) 145 { 146 int i; 147 int error = 0; 148 struct scope6_id *sid = NULL; 149 150 IF_ADDR_WLOCK(ifp); 151 sid = SID(ifp); 152 153 if (!sid) { /* paranoid? */ 154 IF_ADDR_WUNLOCK(ifp); 155 return (EINVAL); 156 } 157 158 /* 159 * XXX: We need more consistency checks of the relationship among 160 * scopes (e.g. an organization should be larger than a site). 161 */ 162 163 /* 164 * TODO(XXX): after setting, we should reflect the changes to 165 * interface addresses, routing table entries, PCB entries... 166 */ 167 168 for (i = 0; i < 16; i++) { 169 if (idlist->s6id_list[i] && 170 idlist->s6id_list[i] != sid->s6id_list[i]) { 171 /* 172 * An interface zone ID must be the corresponding 173 * interface index by definition. 174 */ 175 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL && 176 idlist->s6id_list[i] != ifp->if_index) { 177 IF_ADDR_WUNLOCK(ifp); 178 return (EINVAL); 179 } 180 181 if (i == IPV6_ADDR_SCOPE_LINKLOCAL) { 182 struct epoch_tracker et; 183 184 NET_EPOCH_ENTER(et); 185 if (!ifnet_byindex(idlist->s6id_list[i])) { 186 /* 187 * XXX: theoretically, there should be 188 * no relationship between link IDs and 189 * interface IDs, but we check the 190 * consistency for safety in later use. 191 */ 192 NET_EPOCH_EXIT(et); 193 IF_ADDR_WUNLOCK(ifp); 194 return (EINVAL); 195 } 196 NET_EPOCH_EXIT(et); 197 } 198 199 /* 200 * XXX: we must need lots of work in this case, 201 * but we simply set the new value in this initial 202 * implementation. 203 */ 204 sid->s6id_list[i] = idlist->s6id_list[i]; 205 } 206 } 207 IF_ADDR_WUNLOCK(ifp); 208 209 return (error); 210 } 211 212 static int 213 scope6_get(struct ifnet *ifp, struct scope6_id *idlist) 214 { 215 struct epoch_tracker et; 216 struct scope6_id *sid; 217 218 /* We only need to lock the interface's afdata for SID() to work. */ 219 NET_EPOCH_ENTER(et); 220 sid = SID(ifp); 221 if (sid == NULL) { /* paranoid? */ 222 NET_EPOCH_EXIT(et); 223 return (EINVAL); 224 } 225 226 *idlist = *sid; 227 228 NET_EPOCH_EXIT(et); 229 return (0); 230 } 231 232 /* 233 * Get a scope of the address. Node-local, link-local, site-local or global. 234 */ 235 int 236 in6_addrscope(const struct in6_addr *addr) 237 { 238 239 if (IN6_IS_ADDR_MULTICAST(addr)) { 240 /* 241 * Addresses with reserved value F must be treated as 242 * global multicast addresses. 243 */ 244 if (IPV6_ADDR_MC_SCOPE(addr) == 0x0f) 245 return (IPV6_ADDR_SCOPE_GLOBAL); 246 return (IPV6_ADDR_MC_SCOPE(addr)); 247 } 248 if (IN6_IS_ADDR_LINKLOCAL(addr) || 249 IN6_IS_ADDR_LOOPBACK(addr)) 250 return (IPV6_ADDR_SCOPE_LINKLOCAL); 251 if (IN6_IS_ADDR_SITELOCAL(addr)) 252 return (IPV6_ADDR_SCOPE_SITELOCAL); 253 return (IPV6_ADDR_SCOPE_GLOBAL); 254 } 255 256 /* 257 * ifp - note that this might be NULL 258 */ 259 260 void 261 scope6_setdefault(struct ifnet *ifp) 262 { 263 264 /* 265 * Currently, this function just sets the default "interfaces" 266 * and "links" according to the given interface. 267 * We might eventually have to separate the notion of "link" from 268 * "interface" and provide a user interface to set the default. 269 */ 270 SCOPE6_LOCK(); 271 if (ifp) { 272 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 273 ifp->if_index; 274 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 275 ifp->if_index; 276 } else { 277 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; 278 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; 279 } 280 SCOPE6_UNLOCK(); 281 } 282 283 int 284 scope6_get_default(struct scope6_id *idlist) 285 { 286 287 SCOPE6_LOCK(); 288 *idlist = V_sid_default; 289 SCOPE6_UNLOCK(); 290 291 return (0); 292 } 293 294 u_int32_t 295 scope6_addr2default(struct in6_addr *addr) 296 { 297 u_int32_t id; 298 299 /* 300 * special case: The loopback address should be considered as 301 * link-local, but there's no ambiguity in the syntax. 302 */ 303 if (IN6_IS_ADDR_LOOPBACK(addr)) 304 return (0); 305 306 /* 307 * XXX: 32-bit read is atomic on all our platforms, is it OK 308 * not to lock here? 309 */ 310 SCOPE6_LOCK(); 311 id = V_sid_default.s6id_list[in6_addrscope(addr)]; 312 SCOPE6_UNLOCK(); 313 return (id); 314 } 315 316 /* 317 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID 318 * is unspecified (=0), needs to be specified, and the default zone ID can be 319 * used, the default value will be used. 320 * This routine then generates the kernel-internal form: if the address scope 321 * of is interface-local or link-local, embed the interface index in the 322 * address. 323 */ 324 int 325 sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) 326 { 327 u_int32_t zoneid; 328 329 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) 330 zoneid = scope6_addr2default(&sin6->sin6_addr); 331 332 if (zoneid != 0 && 333 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 334 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { 335 struct epoch_tracker et; 336 337 /* 338 * At this moment, we only check interface-local and 339 * link-local scope IDs, and use interface indices as the 340 * zone IDs assuming a one-to-one mapping between interfaces 341 * and links. 342 */ 343 NET_EPOCH_ENTER(et); 344 if (ifnet_byindex(zoneid) == NULL) { 345 NET_EPOCH_EXIT(et); 346 return (ENXIO); 347 } 348 NET_EPOCH_EXIT(et); 349 350 /* XXX assignment to 16bit from 32bit variable */ 351 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 352 sin6->sin6_scope_id = 0; 353 } 354 355 return 0; 356 } 357 358 /* 359 * generate standard sockaddr_in6 from embedded form. 360 */ 361 int 362 sa6_recoverscope(struct sockaddr_in6 *sin6) 363 { 364 char ip6buf[INET6_ADDRSTRLEN]; 365 u_int32_t zoneid; 366 367 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 368 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { 369 /* 370 * KAME assumption: link id == interface id 371 */ 372 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 373 if (zoneid) { 374 struct epoch_tracker et; 375 376 NET_EPOCH_ENTER(et); 377 /* sanity check */ 378 if (!ifnet_byindex(zoneid)) { 379 NET_EPOCH_EXIT(et); 380 return (ENXIO); 381 } 382 NET_EPOCH_EXIT(et); 383 if (sin6->sin6_scope_id != 0 && 384 zoneid != sin6->sin6_scope_id) { 385 log(LOG_NOTICE, 386 "%s: embedded scope mismatch: %s%%%d. " 387 "sin6_scope_id was overridden\n", __func__, 388 ip6_sprintf(ip6buf, &sin6->sin6_addr), 389 sin6->sin6_scope_id); 390 } 391 sin6->sin6_addr.s6_addr16[1] = 0; 392 sin6->sin6_scope_id = zoneid; 393 } 394 } 395 396 return 0; 397 } 398 399 /* 400 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is 401 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded 402 * in the in6_addr structure, in6 will be modified. 403 * 404 * ret_id - unnecessary? 405 */ 406 int 407 in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id) 408 { 409 int scope; 410 u_int32_t zoneid = 0; 411 struct scope6_id *sid; 412 413 /* 414 * special case: the loopback address can only belong to a loopback 415 * interface. 416 */ 417 if (IN6_IS_ADDR_LOOPBACK(in6)) { 418 if (!(ifp->if_flags & IFF_LOOPBACK)) 419 return (EINVAL); 420 } else { 421 scope = in6_addrscope(in6); 422 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL || 423 scope == IPV6_ADDR_SCOPE_LINKLOCAL) { 424 /* 425 * Currently we use interface indices as the 426 * zone IDs for interface-local and link-local 427 * scopes. 428 */ 429 zoneid = ifp->if_index; 430 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 431 } else if (scope != IPV6_ADDR_SCOPE_GLOBAL) { 432 struct epoch_tracker et; 433 434 NET_EPOCH_ENTER(et); 435 /* XXXGL */ 436 if (ifp->if_inet6 == NULL) { 437 NET_EPOCH_EXIT(et); 438 return (ENETDOWN); 439 } 440 sid = SID(ifp); 441 zoneid = sid->s6id_list[scope]; 442 NET_EPOCH_EXIT(et); 443 } 444 } 445 446 if (ret_id != NULL) 447 *ret_id = zoneid; 448 449 return (0); 450 } 451 452 /* 453 * Just clear the embedded scope identifier. Return 0 if the original address 454 * is intact; return non 0 if the address is modified. 455 */ 456 int 457 in6_clearscope(struct in6_addr *in6) 458 { 459 int modified = 0; 460 461 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 462 if (in6->s6_addr16[1] != 0) 463 modified = 1; 464 in6->s6_addr16[1] = 0; 465 } 466 467 return (modified); 468 } 469 470 /* 471 * Return the scope identifier or zero. 472 */ 473 uint16_t 474 in6_getscope(const struct in6_addr *in6) 475 { 476 477 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) 478 return (in6->s6_addr16[1]); 479 480 return (0); 481 } 482 483 /* 484 * Returns scope zone id for the unicast address @in6. 485 * 486 * Returns 0 for global unicast and loopback addresses. 487 * Returns interface index for the link-local addresses. 488 */ 489 uint32_t 490 in6_get_unicast_scopeid(const struct in6_addr *in6, const struct ifnet *ifp) 491 { 492 493 if (IN6_IS_SCOPE_LINKLOCAL(in6)) 494 return (ifp->if_index); 495 return (0); 496 } 497 498 void 499 in6_set_unicast_scopeid(struct in6_addr *in6, uint32_t scopeid) 500 { 501 502 in6->s6_addr16[1] = htons(scopeid & 0xffff); 503 } 504 505 /* 506 * Return pointer to ifnet structure, corresponding to the zone id of 507 * link-local scope. 508 */ 509 struct ifnet* 510 in6_getlinkifnet(uint32_t zoneid) 511 { 512 struct ifnet *ifp; 513 514 ifp = ifnet_byindex((u_short)zoneid); 515 516 if (ifp == NULL) 517 return (NULL); 518 519 /* An interface might not be IPv6 capable. */ 520 if (ifp->if_inet6 == NULL) { 521 log(LOG_NOTICE, 522 "%s: embedded scope points to an interface without " 523 "IPv6: %s%%%d.\n", __func__, 524 if_name(ifp), zoneid); 525 return (NULL); 526 } 527 528 return (ifp); 529 } 530 531 /* 532 * Return zone id for the specified scope. 533 */ 534 uint32_t 535 in6_getscopezone(const struct ifnet *ifp, int scope) 536 { 537 538 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL || 539 scope == IPV6_ADDR_SCOPE_LINKLOCAL) 540 return (ifp->if_index); 541 if (scope >= 0 && scope < IPV6_ADDR_SCOPES_COUNT) 542 return (SID(ifp)->s6id_list[scope]); 543 return (0); 544 } 545 546 /* 547 * Extracts scope from address @dst, stores cleared address 548 * inside @dst and zone inside @scopeid 549 */ 550 void 551 in6_splitscope(const struct in6_addr *src, struct in6_addr *dst, 552 uint32_t *scopeid) 553 { 554 uint32_t zoneid; 555 556 *dst = *src; 557 zoneid = ntohs(in6_getscope(dst)); 558 in6_clearscope(dst); 559 *scopeid = zoneid; 560 } 561 562 /* 563 * This function is for checking sockaddr_in6 structure passed 564 * from the application level (usually). 565 * 566 * sin6_scope_id should be set for link-local unicast, link-local and 567 * interface-local multicast addresses. 568 * 569 * If it is zero, then look into default zone ids. If default zone id is 570 * not set or disabled, then return error. 571 */ 572 int 573 sa6_checkzone(struct sockaddr_in6 *sa6) 574 { 575 int scope; 576 577 scope = in6_addrscope(&sa6->sin6_addr); 578 if (scope == IPV6_ADDR_SCOPE_GLOBAL) 579 return (sa6->sin6_scope_id ? EINVAL: 0); 580 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr) && 581 scope != IPV6_ADDR_SCOPE_LINKLOCAL && 582 scope != IPV6_ADDR_SCOPE_INTFACELOCAL) { 583 if (sa6->sin6_scope_id == 0 && V_ip6_use_defzone != 0) 584 sa6->sin6_scope_id = V_sid_default.s6id_list[scope]; 585 return (0); 586 } 587 /* 588 * Since ::1 address always configured on the lo0, we can 589 * automatically set its zone id, when it is not specified. 590 * Return error, when specified zone id doesn't match with 591 * actual value. 592 */ 593 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) { 594 if (sa6->sin6_scope_id == 0) 595 sa6->sin6_scope_id = in6_getscopezone(V_loif, scope); 596 else if (sa6->sin6_scope_id != in6_getscopezone(V_loif, scope)) 597 return (EADDRNOTAVAIL); 598 } 599 /* XXX: we can validate sin6_scope_id here */ 600 if (sa6->sin6_scope_id != 0) 601 return (0); 602 if (V_ip6_use_defzone != 0) 603 sa6->sin6_scope_id = V_sid_default.s6id_list[scope]; 604 /* Return error if we can't determine zone id */ 605 return (sa6->sin6_scope_id ? 0: EADDRNOTAVAIL); 606 } 607 608 /* 609 * This function is similar to sa6_checkzone, but it uses given ifp 610 * to initialize sin6_scope_id. 611 */ 612 int 613 sa6_checkzone_ifp(struct ifnet *ifp, struct sockaddr_in6 *sa6) 614 { 615 int scope; 616 617 scope = in6_addrscope(&sa6->sin6_addr); 618 if (scope == IPV6_ADDR_SCOPE_LINKLOCAL || 619 scope == IPV6_ADDR_SCOPE_INTFACELOCAL) { 620 if (sa6->sin6_scope_id == 0) { 621 sa6->sin6_scope_id = in6_getscopezone(ifp, scope); 622 return (0); 623 } else if (sa6->sin6_scope_id != in6_getscopezone(ifp, scope)) 624 return (EADDRNOTAVAIL); 625 } 626 return (sa6_checkzone(sa6)); 627 } 628