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) \ 77 (((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id) 78 79 static int scope6_get(struct ifnet *, struct scope6_id *); 80 static int scope6_set(struct ifnet *, 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 struct scope6_id * 95 scope6_ifattach(struct ifnet *ifp) 96 { 97 struct scope6_id *sid; 98 99 sid = malloc(sizeof(*sid), M_IFADDR, M_WAITOK | M_ZERO); 100 /* 101 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. 102 * Should we rather hardcode here? 103 */ 104 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; 105 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; 106 return (sid); 107 } 108 109 void 110 scope6_ifdetach(struct scope6_id *sid) 111 { 112 113 free(sid, M_IFADDR); 114 } 115 116 int 117 scope6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp) 118 { 119 struct in6_ifreq *ifr; 120 121 if (ifp->if_afdata[AF_INET6] == NULL) 122 return (EPFNOSUPPORT); 123 124 ifr = (struct in6_ifreq *)data; 125 switch (cmd) { 126 case SIOCSSCOPE6: 127 return (scope6_set(ifp, 128 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 129 case SIOCGSCOPE6: 130 return (scope6_get(ifp, 131 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 132 case SIOCGSCOPE6DEF: 133 return (scope6_get_default( 134 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 135 default: 136 return (EOPNOTSUPP); 137 } 138 } 139 140 static int 141 scope6_set(struct ifnet *ifp, struct scope6_id *idlist) 142 { 143 int i; 144 int error = 0; 145 struct scope6_id *sid = NULL; 146 147 IF_AFDATA_WLOCK(ifp); 148 sid = SID(ifp); 149 150 if (!sid) { /* paranoid? */ 151 IF_AFDATA_WUNLOCK(ifp); 152 return (EINVAL); 153 } 154 155 /* 156 * XXX: We need more consistency checks of the relationship among 157 * scopes (e.g. an organization should be larger than a site). 158 */ 159 160 /* 161 * TODO(XXX): after setting, we should reflect the changes to 162 * interface addresses, routing table entries, PCB entries... 163 */ 164 165 for (i = 0; i < 16; i++) { 166 if (idlist->s6id_list[i] && 167 idlist->s6id_list[i] != sid->s6id_list[i]) { 168 /* 169 * An interface zone ID must be the corresponding 170 * interface index by definition. 171 */ 172 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL && 173 idlist->s6id_list[i] != ifp->if_index) { 174 IF_AFDATA_WUNLOCK(ifp); 175 return (EINVAL); 176 } 177 178 if (i == IPV6_ADDR_SCOPE_LINKLOCAL) { 179 struct epoch_tracker et; 180 181 NET_EPOCH_ENTER(et); 182 if (!ifnet_byindex(idlist->s6id_list[i])) { 183 /* 184 * XXX: theoretically, there should be 185 * no relationship between link IDs and 186 * interface IDs, but we check the 187 * consistency for safety in later use. 188 */ 189 NET_EPOCH_EXIT(et); 190 IF_AFDATA_WUNLOCK(ifp); 191 return (EINVAL); 192 } 193 NET_EPOCH_EXIT(et); 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 struct epoch_tracker et; 333 334 /* 335 * At this moment, we only check interface-local and 336 * link-local scope IDs, and use interface indices as the 337 * zone IDs assuming a one-to-one mapping between interfaces 338 * and links. 339 */ 340 NET_EPOCH_ENTER(et); 341 if (ifnet_byindex(zoneid) == NULL) { 342 NET_EPOCH_EXIT(et); 343 return (ENXIO); 344 } 345 NET_EPOCH_EXIT(et); 346 347 /* XXX assignment to 16bit from 32bit variable */ 348 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 349 sin6->sin6_scope_id = 0; 350 } 351 352 return 0; 353 } 354 355 /* 356 * generate standard sockaddr_in6 from embedded form. 357 */ 358 int 359 sa6_recoverscope(struct sockaddr_in6 *sin6) 360 { 361 char ip6buf[INET6_ADDRSTRLEN]; 362 u_int32_t zoneid; 363 364 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 365 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { 366 /* 367 * KAME assumption: link id == interface id 368 */ 369 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 370 if (zoneid) { 371 struct epoch_tracker et; 372 373 NET_EPOCH_ENTER(et); 374 /* sanity check */ 375 if (!ifnet_byindex(zoneid)) { 376 NET_EPOCH_EXIT(et); 377 return (ENXIO); 378 } 379 NET_EPOCH_EXIT(et); 380 if (sin6->sin6_scope_id != 0 && 381 zoneid != sin6->sin6_scope_id) { 382 log(LOG_NOTICE, 383 "%s: embedded scope mismatch: %s%%%d. " 384 "sin6_scope_id was overridden\n", __func__, 385 ip6_sprintf(ip6buf, &sin6->sin6_addr), 386 sin6->sin6_scope_id); 387 } 388 sin6->sin6_addr.s6_addr16[1] = 0; 389 sin6->sin6_scope_id = zoneid; 390 } 391 } 392 393 return 0; 394 } 395 396 /* 397 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is 398 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded 399 * in the in6_addr structure, in6 will be modified. 400 * 401 * ret_id - unnecessary? 402 */ 403 int 404 in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id) 405 { 406 int scope; 407 u_int32_t zoneid = 0; 408 struct scope6_id *sid; 409 410 /* 411 * special case: the loopback address can only belong to a loopback 412 * interface. 413 */ 414 if (IN6_IS_ADDR_LOOPBACK(in6)) { 415 if (!(ifp->if_flags & IFF_LOOPBACK)) 416 return (EINVAL); 417 } else { 418 scope = in6_addrscope(in6); 419 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL || 420 scope == IPV6_ADDR_SCOPE_LINKLOCAL) { 421 /* 422 * Currently we use interface indices as the 423 * zone IDs for interface-local and link-local 424 * scopes. 425 */ 426 zoneid = ifp->if_index; 427 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 428 } else if (scope != IPV6_ADDR_SCOPE_GLOBAL) { 429 struct epoch_tracker et; 430 431 NET_EPOCH_ENTER(et); 432 if (ifp->if_afdata[AF_INET6] == NULL) { 433 NET_EPOCH_EXIT(et); 434 return (ENETDOWN); 435 } 436 sid = SID(ifp); 437 zoneid = sid->s6id_list[scope]; 438 NET_EPOCH_EXIT(et); 439 } 440 } 441 442 if (ret_id != NULL) 443 *ret_id = zoneid; 444 445 return (0); 446 } 447 448 /* 449 * Just clear the embedded scope identifier. Return 0 if the original address 450 * is intact; return non 0 if the address is modified. 451 */ 452 int 453 in6_clearscope(struct in6_addr *in6) 454 { 455 int modified = 0; 456 457 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 458 if (in6->s6_addr16[1] != 0) 459 modified = 1; 460 in6->s6_addr16[1] = 0; 461 } 462 463 return (modified); 464 } 465 466 /* 467 * Return the scope identifier or zero. 468 */ 469 uint16_t 470 in6_getscope(const struct in6_addr *in6) 471 { 472 473 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) 474 return (in6->s6_addr16[1]); 475 476 return (0); 477 } 478 479 /* 480 * Returns scope zone id for the unicast address @in6. 481 * 482 * Returns 0 for global unicast and loopback addresses. 483 * Returns interface index for the link-local addresses. 484 */ 485 uint32_t 486 in6_get_unicast_scopeid(const struct in6_addr *in6, const struct ifnet *ifp) 487 { 488 489 if (IN6_IS_SCOPE_LINKLOCAL(in6)) 490 return (ifp->if_index); 491 return (0); 492 } 493 494 void 495 in6_set_unicast_scopeid(struct in6_addr *in6, uint32_t scopeid) 496 { 497 498 in6->s6_addr16[1] = htons(scopeid & 0xffff); 499 } 500 501 /* 502 * Return pointer to ifnet structure, corresponding to the zone id of 503 * link-local scope. 504 */ 505 struct ifnet* 506 in6_getlinkifnet(uint32_t zoneid) 507 { 508 509 return (ifnet_byindex((u_short)zoneid)); 510 } 511 512 /* 513 * Return zone id for the specified scope. 514 */ 515 uint32_t 516 in6_getscopezone(const struct ifnet *ifp, int scope) 517 { 518 519 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL || 520 scope == IPV6_ADDR_SCOPE_LINKLOCAL) 521 return (ifp->if_index); 522 if (scope >= 0 && scope < IPV6_ADDR_SCOPES_COUNT) 523 return (SID(ifp)->s6id_list[scope]); 524 return (0); 525 } 526 527 /* 528 * Extracts scope from adddress @dst, stores cleared address 529 * inside @dst and zone inside @scopeid 530 */ 531 void 532 in6_splitscope(const struct in6_addr *src, struct in6_addr *dst, 533 uint32_t *scopeid) 534 { 535 uint32_t zoneid; 536 537 *dst = *src; 538 zoneid = ntohs(in6_getscope(dst)); 539 in6_clearscope(dst); 540 *scopeid = zoneid; 541 } 542 543 /* 544 * This function is for checking sockaddr_in6 structure passed 545 * from the application level (usually). 546 * 547 * sin6_scope_id should be set for link-local unicast, link-local and 548 * interface-local multicast addresses. 549 * 550 * If it is zero, then look into default zone ids. If default zone id is 551 * not set or disabled, then return error. 552 */ 553 int 554 sa6_checkzone(struct sockaddr_in6 *sa6) 555 { 556 int scope; 557 558 scope = in6_addrscope(&sa6->sin6_addr); 559 if (scope == IPV6_ADDR_SCOPE_GLOBAL) 560 return (sa6->sin6_scope_id ? EINVAL: 0); 561 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr) && 562 scope != IPV6_ADDR_SCOPE_LINKLOCAL && 563 scope != IPV6_ADDR_SCOPE_INTFACELOCAL) { 564 if (sa6->sin6_scope_id == 0 && V_ip6_use_defzone != 0) 565 sa6->sin6_scope_id = V_sid_default.s6id_list[scope]; 566 return (0); 567 } 568 /* 569 * Since ::1 address always configured on the lo0, we can 570 * automatically set its zone id, when it is not specified. 571 * Return error, when specified zone id doesn't match with 572 * actual value. 573 */ 574 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) { 575 if (sa6->sin6_scope_id == 0) 576 sa6->sin6_scope_id = in6_getscopezone(V_loif, scope); 577 else if (sa6->sin6_scope_id != in6_getscopezone(V_loif, scope)) 578 return (EADDRNOTAVAIL); 579 } 580 /* XXX: we can validate sin6_scope_id here */ 581 if (sa6->sin6_scope_id != 0) 582 return (0); 583 if (V_ip6_use_defzone != 0) 584 sa6->sin6_scope_id = V_sid_default.s6id_list[scope]; 585 /* Return error if we can't determine zone id */ 586 return (sa6->sin6_scope_id ? 0: EADDRNOTAVAIL); 587 } 588 589 /* 590 * This function is similar to sa6_checkzone, but it uses given ifp 591 * to initialize sin6_scope_id. 592 */ 593 int 594 sa6_checkzone_ifp(struct ifnet *ifp, struct sockaddr_in6 *sa6) 595 { 596 int scope; 597 598 scope = in6_addrscope(&sa6->sin6_addr); 599 if (scope == IPV6_ADDR_SCOPE_LINKLOCAL || 600 scope == IPV6_ADDR_SCOPE_INTFACELOCAL) { 601 if (sa6->sin6_scope_id == 0) { 602 sa6->sin6_scope_id = in6_getscopezone(ifp, scope); 603 return (0); 604 } else if (sa6->sin6_scope_id != in6_getscopezone(ifp, scope)) 605 return (EADDRNOTAVAIL); 606 } 607 return (sa6_checkzone(sa6)); 608 } 609