scope6.c revision 207369
1/*- 2 * Copyright (C) 2000 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $ 30 */ 31 32#include <sys/cdefs.h> 33__FBSDID("$FreeBSD: head/sys/netinet6/scope6.c 207369 2010-04-29 11:52:42Z bz $"); 34 35#include <sys/param.h> 36#include <sys/malloc.h> 37#include <sys/mbuf.h> 38#include <sys/socket.h> 39#include <sys/systm.h> 40#include <sys/queue.h> 41#include <sys/syslog.h> 42 43#include <net/if.h> 44#include <net/vnet.h> 45 46#include <netinet/in.h> 47 48#include <netinet/ip6.h> 49#include <netinet6/in6_var.h> 50#include <netinet6/ip6_var.h> 51#include <netinet6/scope6_var.h> 52 53#ifdef ENABLE_DEFAULT_SCOPE 54VNET_DEFINE(int, ip6_use_defzone) = 1; 55#else 56VNET_DEFINE(int, ip6_use_defzone) = 0; 57#endif 58 59/* 60 * The scope6_lock protects the global sid default stored in 61 * sid_default below. 62 */ 63static struct mtx scope6_lock; 64#define SCOPE6_LOCK_INIT() mtx_init(&scope6_lock, "scope6_lock", NULL, MTX_DEF) 65#define SCOPE6_LOCK() mtx_lock(&scope6_lock) 66#define SCOPE6_UNLOCK() mtx_unlock(&scope6_lock) 67#define SCOPE6_LOCK_ASSERT() mtx_assert(&scope6_lock, MA_OWNED) 68 69static VNET_DEFINE(struct scope6_id, sid_default); 70#define V_sid_default VNET(sid_default) 71 72#define SID(ifp) \ 73 (((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id) 74 75void 76scope6_init(void) 77{ 78 79 bzero(&V_sid_default, sizeof(V_sid_default)); 80 81 if (!IS_DEFAULT_VNET(curvnet)) 82 return; 83 84 SCOPE6_LOCK_INIT(); 85} 86 87struct scope6_id * 88scope6_ifattach(struct ifnet *ifp) 89{ 90 struct scope6_id *sid; 91 92 sid = (struct scope6_id *)malloc(sizeof(*sid), M_IFADDR, M_WAITOK); 93 bzero(sid, sizeof(*sid)); 94 95 /* 96 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. 97 * Should we rather hardcode here? 98 */ 99 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; 100 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; 101#ifdef MULTI_SCOPE 102 /* by default, we don't care about scope boundary for these scopes. */ 103 sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1; 104 sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1; 105#endif 106 107 return sid; 108} 109 110void 111scope6_ifdetach(struct scope6_id *sid) 112{ 113 114 free(sid, M_IFADDR); 115} 116 117int 118scope6_set(struct ifnet *ifp, struct scope6_id *idlist) 119{ 120 int i; 121 int error = 0; 122 struct scope6_id *sid = NULL; 123 124 IF_AFDATA_LOCK(ifp); 125 sid = SID(ifp); 126 127 if (!sid) { /* paranoid? */ 128 IF_AFDATA_UNLOCK(ifp); 129 return (EINVAL); 130 } 131 132 /* 133 * XXX: We need more consistency checks of the relationship among 134 * scopes (e.g. an organization should be larger than a site). 135 */ 136 137 /* 138 * TODO(XXX): after setting, we should reflect the changes to 139 * interface addresses, routing table entries, PCB entries... 140 */ 141 142 SCOPE6_LOCK(); 143 for (i = 0; i < 16; i++) { 144 if (idlist->s6id_list[i] && 145 idlist->s6id_list[i] != sid->s6id_list[i]) { 146 /* 147 * An interface zone ID must be the corresponding 148 * interface index by definition. 149 */ 150 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL && 151 idlist->s6id_list[i] != ifp->if_index) { 152 IF_AFDATA_UNLOCK(ifp); 153 SCOPE6_UNLOCK(); 154 return (EINVAL); 155 } 156 157 if (i == IPV6_ADDR_SCOPE_LINKLOCAL && 158 idlist->s6id_list[i] > V_if_index) { 159 /* 160 * XXX: theoretically, there should be no 161 * relationship between link IDs and interface 162 * IDs, but we check the consistency for 163 * safety in later use. 164 */ 165 IF_AFDATA_UNLOCK(ifp); 166 SCOPE6_UNLOCK(); 167 return (EINVAL); 168 } 169 170 /* 171 * XXX: we must need lots of work in this case, 172 * but we simply set the new value in this initial 173 * implementation. 174 */ 175 sid->s6id_list[i] = idlist->s6id_list[i]; 176 } 177 } 178 SCOPE6_UNLOCK(); 179 IF_AFDATA_UNLOCK(ifp); 180 181 return (error); 182} 183 184int 185scope6_get(struct ifnet *ifp, struct scope6_id *idlist) 186{ 187 /* We only need to lock the interface's afdata for SID() to work. */ 188 IF_AFDATA_LOCK(ifp); 189 struct scope6_id *sid = SID(ifp); 190 191 if (sid == NULL) { /* paranoid? */ 192 IF_AFDATA_UNLOCK(ifp); 193 return (EINVAL); 194 } 195 196 SCOPE6_LOCK(); 197 *idlist = *sid; 198 SCOPE6_UNLOCK(); 199 200 IF_AFDATA_UNLOCK(ifp); 201 return (0); 202} 203 204 205/* 206 * Get a scope of the address. Node-local, link-local, site-local or global. 207 */ 208int 209in6_addrscope(struct in6_addr *addr) 210{ 211 int scope; 212 213 if (addr->s6_addr[0] == 0xfe) { 214 scope = addr->s6_addr[1] & 0xc0; 215 216 switch (scope) { 217 case 0x80: 218 return IPV6_ADDR_SCOPE_LINKLOCAL; 219 break; 220 case 0xc0: 221 return IPV6_ADDR_SCOPE_SITELOCAL; 222 break; 223 default: 224 return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */ 225 break; 226 } 227 } 228 229 230 if (addr->s6_addr[0] == 0xff) { 231 scope = addr->s6_addr[1] & 0x0f; 232 233 /* 234 * due to other scope such as reserved, 235 * return scope doesn't work. 236 */ 237 switch (scope) { 238 case IPV6_ADDR_SCOPE_INTFACELOCAL: 239 return IPV6_ADDR_SCOPE_INTFACELOCAL; 240 break; 241 case IPV6_ADDR_SCOPE_LINKLOCAL: 242 return IPV6_ADDR_SCOPE_LINKLOCAL; 243 break; 244 case IPV6_ADDR_SCOPE_SITELOCAL: 245 return IPV6_ADDR_SCOPE_SITELOCAL; 246 break; 247 default: 248 return IPV6_ADDR_SCOPE_GLOBAL; 249 break; 250 } 251 } 252 253 /* 254 * Regard loopback and unspecified addresses as global, since 255 * they have no ambiguity. 256 */ 257 if (bcmp(&in6addr_loopback, addr, sizeof(*addr) - 1) == 0) { 258 if (addr->s6_addr[15] == 1) /* loopback */ 259 return IPV6_ADDR_SCOPE_LINKLOCAL; 260 if (addr->s6_addr[15] == 0) /* unspecified */ 261 return IPV6_ADDR_SCOPE_GLOBAL; /* XXX: correct? */ 262 } 263 264 return IPV6_ADDR_SCOPE_GLOBAL; 265} 266 267/* 268 * ifp - note that this might be NULL 269 */ 270 271void 272scope6_setdefault(struct ifnet *ifp) 273{ 274 275 /* 276 * Currently, this function just sets the default "interfaces" 277 * and "links" according to the given interface. 278 * We might eventually have to separate the notion of "link" from 279 * "interface" and provide a user interface to set the default. 280 */ 281 SCOPE6_LOCK(); 282 if (ifp) { 283 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 284 ifp->if_index; 285 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 286 ifp->if_index; 287 } else { 288 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; 289 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; 290 } 291 SCOPE6_UNLOCK(); 292} 293 294int 295scope6_get_default(struct scope6_id *idlist) 296{ 297 298 SCOPE6_LOCK(); 299 *idlist = V_sid_default; 300 SCOPE6_UNLOCK(); 301 302 return (0); 303} 304 305u_int32_t 306scope6_addr2default(struct in6_addr *addr) 307{ 308 u_int32_t id; 309 310 /* 311 * special case: The loopback address should be considered as 312 * link-local, but there's no ambiguity in the syntax. 313 */ 314 if (IN6_IS_ADDR_LOOPBACK(addr)) 315 return (0); 316 317 /* 318 * XXX: 32-bit read is atomic on all our platforms, is it OK 319 * not to lock here? 320 */ 321 SCOPE6_LOCK(); 322 id = V_sid_default.s6id_list[in6_addrscope(addr)]; 323 SCOPE6_UNLOCK(); 324 return (id); 325} 326 327/* 328 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID 329 * is unspecified (=0), needs to be specified, and the default zone ID can be 330 * used, the default value will be used. 331 * This routine then generates the kernel-internal form: if the address scope 332 * of is interface-local or link-local, embed the interface index in the 333 * address. 334 */ 335int 336sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) 337{ 338 struct ifnet *ifp; 339 u_int32_t zoneid; 340 341 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) 342 zoneid = scope6_addr2default(&sin6->sin6_addr); 343 344 if (zoneid != 0 && 345 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 346 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { 347 /* 348 * At this moment, we only check interface-local and 349 * link-local scope IDs, and use interface indices as the 350 * zone IDs assuming a one-to-one mapping between interfaces 351 * and links. 352 */ 353 if (V_if_index < zoneid) 354 return (ENXIO); 355 ifp = ifnet_byindex(zoneid); 356 if (ifp == NULL) /* XXX: this can happen for some OS */ 357 return (ENXIO); 358 359 /* XXX assignment to 16bit from 32bit variable */ 360 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 361 362 sin6->sin6_scope_id = 0; 363 } 364 365 return 0; 366} 367 368/* 369 * generate standard sockaddr_in6 from embedded form. 370 */ 371int 372sa6_recoverscope(struct sockaddr_in6 *sin6) 373{ 374 char ip6buf[INET6_ADDRSTRLEN]; 375 u_int32_t zoneid; 376 377 if (sin6->sin6_scope_id != 0) { 378 log(LOG_NOTICE, 379 "sa6_recoverscope: assumption failure (non 0 ID): %s%%%d\n", 380 ip6_sprintf(ip6buf, &sin6->sin6_addr), sin6->sin6_scope_id); 381 /* XXX: proceed anyway... */ 382 } 383 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 384 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { 385 /* 386 * KAME assumption: link id == interface id 387 */ 388 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 389 if (zoneid) { 390 /* sanity check */ 391 if (zoneid < 0 || V_if_index < zoneid) 392 return (ENXIO); 393 if (!ifnet_byindex(zoneid)) 394 return (ENXIO); 395 sin6->sin6_addr.s6_addr16[1] = 0; 396 sin6->sin6_scope_id = zoneid; 397 } 398 } 399 400 return 0; 401} 402 403/* 404 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is 405 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded 406 * in the in6_addr structure, in6 will be modified. 407 * 408 * ret_id - unnecessary? 409 */ 410int 411in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id) 412{ 413 int scope; 414 u_int32_t zoneid = 0; 415 struct scope6_id *sid; 416 417 IF_AFDATA_LOCK(ifp); 418 419 sid = SID(ifp); 420 421#ifdef DIAGNOSTIC 422 if (sid == NULL) { /* should not happen */ 423 panic("in6_setscope: scope array is NULL"); 424 /* NOTREACHED */ 425 } 426#endif 427 428 /* 429 * special case: the loopback address can only belong to a loopback 430 * interface. 431 */ 432 if (IN6_IS_ADDR_LOOPBACK(in6)) { 433 if (!(ifp->if_flags & IFF_LOOPBACK)) { 434 IF_AFDATA_UNLOCK(ifp); 435 return (EINVAL); 436 } else { 437 if (ret_id != NULL) 438 *ret_id = 0; /* there's no ambiguity */ 439 IF_AFDATA_UNLOCK(ifp); 440 return (0); 441 } 442 } 443 444 scope = in6_addrscope(in6); 445 446 SCOPE6_LOCK(); 447 switch (scope) { 448 case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */ 449 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL]; 450 break; 451 452 case IPV6_ADDR_SCOPE_LINKLOCAL: 453 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL]; 454 break; 455 456 case IPV6_ADDR_SCOPE_SITELOCAL: 457 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL]; 458 break; 459 460 case IPV6_ADDR_SCOPE_ORGLOCAL: 461 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL]; 462 break; 463 464 default: 465 zoneid = 0; /* XXX: treat as global. */ 466 break; 467 } 468 SCOPE6_UNLOCK(); 469 IF_AFDATA_UNLOCK(ifp); 470 471 if (ret_id != NULL) 472 *ret_id = zoneid; 473 474 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) 475 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 476 477 return (0); 478} 479 480/* 481 * Just clear the embedded scope identifier. Return 0 if the original address 482 * is intact; return non 0 if the address is modified. 483 */ 484int 485in6_clearscope(struct in6_addr *in6) 486{ 487 int modified = 0; 488 489 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 490 if (in6->s6_addr16[1] != 0) 491 modified = 1; 492 in6->s6_addr16[1] = 0; 493 } 494 495 return (modified); 496} 497