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