1 /* $NetBSD: scope6.c,v 1.8 2009/09/11 22:06:29 dyoung Exp $ */ 2 /* $KAME$ */ 3 4 /*- 5 * Copyright (C) 2000 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: scope6.c,v 1.8 2009/09/11 22:06:29 dyoung Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/malloc.h> 38 #include <sys/mbuf.h> 39 #include <sys/socket.h> 40 #include <sys/systm.h> 41 #include <sys/queue.h> 42 #include <sys/syslog.h> 43 44 #include <net/route.h> 45 #include <net/if.h> 46 47 #include <netinet/in.h> 48 49 #include <netinet6/in6_var.h> 50 #include <netinet6/scope6_var.h> 51 52 #ifdef ENABLE_DEFAULT_SCOPE 53 int ip6_use_defzone = 1; 54 #else 55 int ip6_use_defzone = 0; 56 #endif 57 58 static struct scope6_id sid_default; 59 #define SID(ifp) \ 60 (((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id) 61 62 void 63 scope6_init(void) 64 { 65 66 memset(&sid_default, 0, sizeof(sid_default)); 67 } 68 69 struct scope6_id * 70 scope6_ifattach(struct ifnet *ifp) 71 { 72 struct scope6_id *sid; 73 74 sid = (struct scope6_id *)malloc(sizeof(*sid), M_IFADDR, M_WAITOK); 75 memset(sid, 0, sizeof(*sid)); 76 77 /* 78 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. 79 * Should we rather hardcode here? 80 */ 81 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; 82 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; 83 #ifdef MULTI_SCOPE 84 /* by default, we don't care about scope boundary for these scopes. */ 85 sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1; 86 sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1; 87 #endif 88 89 return sid; 90 } 91 92 void 93 scope6_ifdetach(struct scope6_id *sid) 94 { 95 96 free(sid, M_IFADDR); 97 } 98 99 int 100 scope6_set(struct ifnet *ifp, const struct scope6_id *idlist) 101 { 102 int i; 103 int error = 0; 104 struct scope6_id *sid = NULL; 105 106 sid = SID(ifp); 107 108 if (!sid) /* paranoid? */ 109 return (EINVAL); 110 111 /* 112 * XXX: We need more consistency checks of the relationship among 113 * scopes (e.g. an organization should be larger than a site). 114 */ 115 116 /* 117 * TODO(XXX): after setting, we should reflect the changes to 118 * interface addresses, routing table entries, PCB entries... 119 */ 120 121 for (i = 0; i < 16; i++) { 122 if (idlist->s6id_list[i] && 123 idlist->s6id_list[i] != sid->s6id_list[i]) { 124 /* 125 * An interface zone ID must be the corresponding 126 * interface index by definition. 127 */ 128 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL && 129 idlist->s6id_list[i] != ifp->if_index) 130 return (EINVAL); 131 132 if (i == IPV6_ADDR_SCOPE_LINKLOCAL && 133 idlist->s6id_list[i] >= if_indexlim) { 134 /* 135 * XXX: theoretically, there should be no 136 * relationship between link IDs and interface 137 * IDs, but we check the consistency for 138 * safety in later use. 139 */ 140 return (EINVAL); 141 } 142 143 /* 144 * XXX: we must need lots of work in this case, 145 * but we simply set the new value in this initial 146 * implementation. 147 */ 148 sid->s6id_list[i] = idlist->s6id_list[i]; 149 } 150 } 151 152 return (error); 153 } 154 155 int 156 scope6_get(const struct ifnet *ifp, struct scope6_id *idlist) 157 { 158 /* We only need to lock the interface's afdata for SID() to work. */ 159 const struct scope6_id *sid = SID(ifp); 160 161 if (sid == NULL) /* paranoid? */ 162 return EINVAL; 163 164 *idlist = *sid; 165 166 return 0; 167 } 168 169 /* 170 * Get a scope of the address. Interface-local, link-local, site-local 171 * or global. 172 */ 173 int 174 in6_addrscope(const struct in6_addr *addr) 175 { 176 int scope; 177 178 if (addr->s6_addr[0] == 0xfe) { 179 scope = addr->s6_addr[1] & 0xc0; 180 181 switch (scope) { 182 case 0x80: 183 return IPV6_ADDR_SCOPE_LINKLOCAL; 184 break; 185 case 0xc0: 186 return IPV6_ADDR_SCOPE_SITELOCAL; 187 break; 188 default: 189 return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */ 190 break; 191 } 192 } 193 194 195 if (addr->s6_addr[0] == 0xff) { 196 scope = addr->s6_addr[1] & 0x0f; 197 198 /* 199 * due to other scope such as reserved, 200 * return scope doesn't work. 201 */ 202 switch (scope) { 203 case IPV6_ADDR_SCOPE_INTFACELOCAL: 204 return IPV6_ADDR_SCOPE_INTFACELOCAL; 205 break; 206 case IPV6_ADDR_SCOPE_LINKLOCAL: 207 return IPV6_ADDR_SCOPE_LINKLOCAL; 208 break; 209 case IPV6_ADDR_SCOPE_SITELOCAL: 210 return IPV6_ADDR_SCOPE_SITELOCAL; 211 break; 212 default: 213 return IPV6_ADDR_SCOPE_GLOBAL; 214 break; 215 } 216 } 217 218 if (memcmp(&in6addr_loopback, addr, sizeof(*addr) - 1) == 0) { 219 if (addr->s6_addr[15] == 1) /* loopback */ 220 return IPV6_ADDR_SCOPE_LINKLOCAL; 221 if (addr->s6_addr[15] == 0) { 222 /* 223 * Regard the unspecified addresses as global, 224 * since it has no ambiguity. 225 * XXX: not sure if it's correct... 226 */ 227 return IPV6_ADDR_SCOPE_GLOBAL; 228 } 229 } 230 231 return IPV6_ADDR_SCOPE_GLOBAL; 232 } 233 234 /* note that ifp argument might be NULL */ 235 void 236 scope6_setdefault(struct ifnet *ifp) 237 { 238 239 /* 240 * Currently, this function just sets the default "interfaces" 241 * and "links" according to the given interface. 242 * We might eventually have to separate the notion of "link" from 243 * "interface" and provide a user interface to set the default. 244 */ 245 if (ifp) { 246 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 247 ifp->if_index; 248 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 249 ifp->if_index; 250 } else { 251 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; 252 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; 253 } 254 } 255 256 int 257 scope6_get_default(struct scope6_id *idlist) 258 { 259 260 *idlist = sid_default; 261 262 return (0); 263 } 264 265 uint32_t 266 scope6_addr2default(const struct in6_addr *addr) 267 { 268 uint32_t id; 269 270 /* 271 * special case: The loopback address should be considered as 272 * link-local, but there's no ambiguity in the syntax. 273 */ 274 if (IN6_IS_ADDR_LOOPBACK(addr)) 275 return (0); 276 277 /* 278 * XXX: 32-bit read is atomic on all our platforms, is it OK 279 * not to lock here? 280 */ 281 id = sid_default.s6id_list[in6_addrscope(addr)]; 282 283 return (id); 284 } 285 286 /* 287 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID 288 * is unspecified (=0), needs to be specified, and the default zone ID can be 289 * used, the default value will be used. 290 * This routine then generates the kernel-internal form: if the address scope 291 * of is interface-local or link-local, embed the interface index in the 292 * address. 293 */ 294 int 295 sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) 296 { 297 struct ifnet *ifp; 298 uint32_t zoneid; 299 300 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) 301 zoneid = scope6_addr2default(&sin6->sin6_addr); 302 303 if (zoneid != 0 && 304 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 305 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { 306 /* 307 * At this moment, we only check interface-local and 308 * link-local scope IDs, and use interface indices as the 309 * zone IDs assuming a one-to-one mapping between interfaces 310 * and links. 311 */ 312 if (if_indexlim <= zoneid) 313 return (ENXIO); 314 #ifdef __FreeBSD__ 315 ifp = ifnet_byindex(zoneid); 316 #else 317 ifp = ifindex2ifnet[zoneid]; 318 #endif 319 if (ifp == NULL) /* XXX: this can happen for some OS */ 320 return (ENXIO); 321 322 /* XXX assignment to 16bit from 32bit variable */ 323 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 324 325 sin6->sin6_scope_id = 0; 326 } 327 328 return 0; 329 } 330 331 struct sockaddr * 332 sockaddr_in6_externalize(struct sockaddr *dst, socklen_t socklen, 333 const struct sockaddr *src) 334 { 335 struct sockaddr_in6 *sin6; 336 337 sin6 = satosin6(sockaddr_copy(dst, socklen, src)); 338 339 if (sin6 == NULL || sa6_recoverscope(sin6) != 0) 340 return NULL; 341 342 return dst; 343 } 344 345 /* 346 * generate standard sockaddr_in6 from embedded form. 347 */ 348 int 349 sa6_recoverscope(struct sockaddr_in6 *sin6) 350 { 351 uint32_t zoneid; 352 353 if (sin6->sin6_scope_id != 0) { 354 log(LOG_NOTICE, 355 "sa6_recoverscope: assumption failure (non 0 ID): %s%%%d\n", 356 ip6_sprintf(&sin6->sin6_addr), sin6->sin6_scope_id); 357 /* XXX: proceed anyway... */ 358 } 359 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 360 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { 361 /* 362 * KAME assumption: link id == interface id 363 */ 364 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 365 if (zoneid) { 366 /* sanity check */ 367 if (/* zoneid < 0 || */ if_indexlim <= zoneid) 368 return (ENXIO); 369 #ifdef __FreeBSD__ 370 if (!ifnet_byindex(zoneid)) 371 #else 372 if (!ifindex2ifnet[zoneid]) 373 #endif 374 return (ENXIO); 375 sin6->sin6_addr.s6_addr16[1] = 0; 376 sin6->sin6_scope_id = zoneid; 377 } 378 } 379 380 return 0; 381 } 382 383 int 384 in6_setzoneid(struct in6_addr *in6, uint32_t zoneid) 385 { 386 if (IN6_IS_SCOPE_EMBEDDABLE(in6)) 387 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 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 int 398 in6_setscope(struct in6_addr *in6, const struct ifnet *ifp, uint32_t *ret_id) 399 { 400 int scope; 401 uint32_t zoneid = 0; 402 const struct scope6_id *sid = SID(ifp); 403 404 #ifdef DIAGNOSTIC 405 if (sid == NULL) { /* should not happen */ 406 panic("in6_setscope: scope array is NULL"); 407 /* NOTREACHED */ 408 } 409 #endif 410 411 /* 412 * special case: the loopback address can only belong to a loopback 413 * interface. 414 */ 415 if (IN6_IS_ADDR_LOOPBACK(in6)) { 416 if (!(ifp->if_flags & IFF_LOOPBACK)) 417 return (EINVAL); 418 else { 419 if (ret_id != NULL) 420 *ret_id = 0; /* there's no ambiguity */ 421 return (0); 422 } 423 } 424 425 scope = in6_addrscope(in6); 426 427 if (!sid->s6id_list) 428 return 0; 429 430 switch (scope) { 431 case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */ 432 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL]; 433 break; 434 435 case IPV6_ADDR_SCOPE_LINKLOCAL: 436 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL]; 437 break; 438 439 case IPV6_ADDR_SCOPE_SITELOCAL: 440 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL]; 441 break; 442 443 case IPV6_ADDR_SCOPE_ORGLOCAL: 444 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL]; 445 break; 446 447 default: 448 zoneid = 0; /* XXX: treat as global. */ 449 break; 450 } 451 452 if (ret_id != NULL) 453 *ret_id = zoneid; 454 455 return in6_setzoneid(in6, zoneid); 456 } 457 458 /* 459 * Just clear the embedded scope identifier. Return 0 if the original address 460 * is intact; return non 0 if the address is modified. 461 */ 462 int 463 in6_clearscope(struct in6_addr *in6) 464 { 465 int modified = 0; 466 467 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 468 if (in6->s6_addr16[1] != 0) 469 modified = 1; 470 in6->s6_addr16[1] = 0; 471 } 472 473 return (modified); 474 } 475