1 /* $NetBSD: scope6.c,v 1.20 2018/05/01 07:21:39 maxv 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 1.20 2018/05/01 07:21:39 maxv 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/if.h> 45 46 #include <netinet/in.h> 47 48 #include <netinet6/in6_var.h> 49 #include <netinet6/scope6_var.h> 50 51 #ifdef ENABLE_DEFAULT_SCOPE 52 int ip6_use_defzone = 1; 53 #else 54 int ip6_use_defzone = 0; 55 #endif 56 57 static struct scope6_id sid_default; 58 #define SID(ifp) \ 59 ((ifp)->if_afdata[AF_INET6] == NULL ? NULL : \ 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 = malloc(sizeof(*sid), M_IFADDR, M_WAITOK | M_ZERO); 75 76 /* 77 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. 78 * Should we rather hardcode here? 79 */ 80 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; 81 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; 82 #ifdef MULTI_SCOPE 83 /* by default, we don't care about scope boundary for these scopes. */ 84 sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1; 85 sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1; 86 #endif 87 88 return sid; 89 } 90 91 void 92 scope6_ifdetach(struct scope6_id *sid) 93 { 94 95 free(sid, M_IFADDR); 96 } 97 98 int 99 scope6_set(struct ifnet *ifp, const struct scope6_id *idlist) 100 { 101 int i; 102 int error = 0; 103 struct scope6_id *sid = SID(ifp); 104 105 if (!sid) /* paranoid? */ 106 return EINVAL; 107 108 /* 109 * XXX: We need more consistency checks of the relationship among 110 * scopes (e.g. an organization should be larger than a site). 111 */ 112 113 /* 114 * TODO(XXX): after setting, we should reflect the changes to 115 * interface addresses, routing table entries, PCB entries... 116 */ 117 118 for (i = 0; i < 16; i++) { 119 if (idlist->s6id_list[i] && 120 idlist->s6id_list[i] != sid->s6id_list[i]) { 121 int s; 122 /* 123 * An interface zone ID must be the corresponding 124 * interface index by definition. 125 */ 126 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL && 127 idlist->s6id_list[i] != ifp->if_index) 128 return EINVAL; 129 130 s = pserialize_read_enter(); 131 if (i == IPV6_ADDR_SCOPE_LINKLOCAL && 132 !if_byindex(idlist->s6id_list[i])) { 133 /* 134 * XXX: theoretically, there should be no 135 * relationship between link IDs and interface 136 * IDs, but we check the consistency for 137 * safety in later use. 138 */ 139 pserialize_read_exit(s); 140 return EINVAL; 141 } 142 pserialize_read_exit(s); 143 144 /* 145 * XXX: we must need lots of work in this case, 146 * but we simply set the new value in this initial 147 * implementation. 148 */ 149 sid->s6id_list[i] = idlist->s6id_list[i]; 150 } 151 } 152 153 return error; 154 } 155 156 int 157 scope6_get(const struct ifnet *ifp, struct scope6_id *idlist) 158 { 159 /* We only need to lock the interface's afdata for SID() to work. */ 160 const struct scope6_id *sid = SID(ifp); 161 162 if (sid == NULL) /* paranoid? */ 163 return EINVAL; 164 165 *idlist = *sid; 166 167 return 0; 168 } 169 170 /* 171 * Get a scope of the address. Interface-local, link-local, site-local 172 * or global. 173 */ 174 int 175 in6_addrscope(const struct in6_addr *addr) 176 { 177 int scope; 178 179 if (addr->s6_addr[0] == 0xfe) { 180 scope = addr->s6_addr[1] & 0xc0; 181 182 switch (scope) { 183 case 0x80: 184 return IPV6_ADDR_SCOPE_LINKLOCAL; 185 case 0xc0: 186 return IPV6_ADDR_SCOPE_SITELOCAL; 187 default: 188 return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */ 189 } 190 } 191 192 if (addr->s6_addr[0] == 0xff) { 193 scope = addr->s6_addr[1] & 0x0f; 194 195 /* 196 * due to other scope such as reserved, 197 * return scope doesn't work. 198 */ 199 switch (scope) { 200 case IPV6_ADDR_SCOPE_INTFACELOCAL: 201 return IPV6_ADDR_SCOPE_INTFACELOCAL; 202 case IPV6_ADDR_SCOPE_LINKLOCAL: 203 return IPV6_ADDR_SCOPE_LINKLOCAL; 204 case IPV6_ADDR_SCOPE_SITELOCAL: 205 return IPV6_ADDR_SCOPE_SITELOCAL; 206 default: 207 return IPV6_ADDR_SCOPE_GLOBAL; 208 } 209 } 210 211 if (memcmp(&in6addr_loopback, addr, sizeof(*addr) - 1) == 0) { 212 if (addr->s6_addr[15] == 1) /* loopback */ 213 return IPV6_ADDR_SCOPE_LINKLOCAL; 214 if (addr->s6_addr[15] == 0) { 215 /* 216 * Regard the unspecified addresses as global, 217 * since it has no ambiguity. 218 * XXX: not sure if it's correct... 219 */ 220 return IPV6_ADDR_SCOPE_GLOBAL; 221 } 222 } 223 224 return IPV6_ADDR_SCOPE_GLOBAL; 225 } 226 227 /* note that ifp argument might be NULL */ 228 void 229 scope6_setdefault(struct ifnet *ifp) 230 { 231 232 /* 233 * Currently, this function just sets the default "interfaces" 234 * and "links" according to the given interface. 235 * We might eventually have to separate the notion of "link" from 236 * "interface" and provide a user interface to set the default. 237 */ 238 if (ifp) { 239 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 240 ifp->if_index; 241 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 242 ifp->if_index; 243 } else { 244 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; 245 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; 246 } 247 } 248 249 int 250 scope6_get_default(struct scope6_id *idlist) 251 { 252 253 *idlist = sid_default; 254 255 return 0; 256 } 257 258 uint32_t 259 scope6_addr2default(const struct in6_addr *addr) 260 { 261 uint32_t id; 262 263 /* 264 * special case: The loopback address should be considered as 265 * link-local, but there's no ambiguity in the syntax. 266 */ 267 if (IN6_IS_ADDR_LOOPBACK(addr)) 268 return 0; 269 270 /* 271 * XXX: 32-bit read is atomic on all our platforms, is it OK 272 * not to lock here? 273 */ 274 id = sid_default.s6id_list[in6_addrscope(addr)]; 275 276 return id; 277 } 278 279 /* 280 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID 281 * is unspecified (=0), needs to be specified, and the default zone ID can be 282 * used, the default value will be used. 283 * This routine then generates the kernel-internal form: if the address scope 284 * of is interface-local or link-local, embed the interface index in the 285 * address. 286 */ 287 int 288 sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) 289 { 290 struct ifnet *ifp; 291 uint32_t zoneid; 292 293 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) 294 zoneid = scope6_addr2default(&sin6->sin6_addr); 295 296 if (zoneid != 0 && 297 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 298 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { 299 int s; 300 /* 301 * At this moment, we only check interface-local and 302 * link-local scope IDs, and use interface indices as the 303 * zone IDs assuming a one-to-one mapping between interfaces 304 * and links. 305 */ 306 s = pserialize_read_enter(); 307 ifp = if_byindex(zoneid); 308 if (ifp == NULL) { 309 pserialize_read_exit(s); 310 return ENXIO; 311 } 312 pserialize_read_exit(s); 313 314 /* XXX assignment to 16bit from 32bit variable */ 315 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 316 317 sin6->sin6_scope_id = 0; 318 } 319 320 return 0; 321 } 322 323 struct sockaddr * 324 sockaddr_in6_externalize(struct sockaddr *dst, socklen_t socklen, 325 const struct sockaddr *src) 326 { 327 struct sockaddr_in6 *sin6; 328 329 sin6 = satosin6(sockaddr_copy(dst, socklen, src)); 330 331 if (sin6 == NULL || sa6_recoverscope(sin6) != 0) 332 return NULL; 333 334 return dst; 335 } 336 337 /* 338 * generate standard sockaddr_in6 from embedded form. 339 */ 340 int 341 sa6_recoverscope(struct sockaddr_in6 *sin6) 342 { 343 uint32_t zoneid; 344 char ip6buf[INET6_ADDRSTRLEN]; 345 346 if (sin6->sin6_scope_id != 0) { 347 log(LOG_NOTICE, 348 "%s: assumption failure (non 0 ID): %s%%%d\n", __func__, 349 IN6_PRINT(ip6buf, &sin6->sin6_addr), sin6->sin6_scope_id); 350 /* XXX: proceed anyway... */ 351 } 352 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 353 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { 354 /* 355 * KAME assumption: link id == interface id 356 */ 357 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 358 if (zoneid) { 359 int s = pserialize_read_enter(); 360 if (!if_byindex(zoneid)) { 361 pserialize_read_exit(s); 362 return ENXIO; 363 } 364 pserialize_read_exit(s); 365 sin6->sin6_addr.s6_addr16[1] = 0; 366 sin6->sin6_scope_id = zoneid; 367 } 368 } 369 370 return 0; 371 } 372 373 int 374 in6_setzoneid(struct in6_addr *in6, uint32_t zoneid) 375 { 376 if (IN6_IS_SCOPE_EMBEDDABLE(in6)) 377 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 378 379 return 0; 380 } 381 382 /* 383 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is 384 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded 385 * in the in6_addr structure, in6 will be modified. 386 */ 387 int 388 in6_setscope(struct in6_addr *in6, const struct ifnet *ifp, uint32_t *ret_id) 389 { 390 int scope; 391 uint32_t zoneid = 0; 392 const struct scope6_id *sid = SID(ifp); 393 394 if (sid == NULL) { 395 log(LOG_NOTICE, "%s: no scope id for %s\n", __func__, 396 if_name(ifp)); 397 return EINVAL; 398 } 399 400 /* 401 * special case: the loopback address can only belong to a loopback 402 * interface. 403 */ 404 if (IN6_IS_ADDR_LOOPBACK(in6)) { 405 if (!(ifp->if_flags & IFF_LOOPBACK)) { 406 char ip6buf[INET6_ADDRSTRLEN]; 407 log(LOG_NOTICE, "%s: can't set scope for not loopback " 408 "interface %s and loopback address %s\n", 409 __func__, if_name(ifp), IN6_PRINT(ip6buf, in6)); 410 return EINVAL; 411 } else { 412 if (ret_id != NULL) 413 *ret_id = 0; /* there's no ambiguity */ 414 return 0; 415 } 416 } 417 418 scope = in6_addrscope(in6); 419 420 switch (scope) { 421 case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */ 422 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL]; 423 break; 424 425 case IPV6_ADDR_SCOPE_LINKLOCAL: 426 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL]; 427 break; 428 429 case IPV6_ADDR_SCOPE_SITELOCAL: 430 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL]; 431 break; 432 433 case IPV6_ADDR_SCOPE_ORGLOCAL: 434 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL]; 435 break; 436 437 default: 438 zoneid = 0; /* XXX: treat as global. */ 439 break; 440 } 441 442 if (ret_id != NULL) 443 *ret_id = zoneid; 444 445 return in6_setzoneid(in6, zoneid); 446 } 447 448 const char * 449 in6_getscopename(const struct in6_addr *addr) 450 { 451 switch (in6_addrscope(addr)) { 452 case IPV6_ADDR_SCOPE_INTFACELOCAL: 453 return "interface"; 454 #if IPV6_ADDR_SCOPE_INTFACELOCAL != IPV6_ADDR_SCOPE_NODELOCAL 455 case IPV6_ADDR_SCOPE_NODELOCAL: 456 return "node"; 457 #endif 458 case IPV6_ADDR_SCOPE_LINKLOCAL: 459 return "link"; 460 case IPV6_ADDR_SCOPE_SITELOCAL: 461 return "site"; 462 case IPV6_ADDR_SCOPE_ORGLOCAL: 463 return "organization"; 464 case IPV6_ADDR_SCOPE_GLOBAL: 465 return "global"; 466 default: 467 return "unknown"; 468 } 469 } 470 471 /* 472 * Just clear the embedded scope identifier. Return 0 if the original address 473 * is intact; return non 0 if the address is modified. 474 */ 475 int 476 in6_clearscope(struct in6_addr *in6) 477 { 478 int modified = 0; 479 480 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 481 if (in6->s6_addr16[1] != 0) 482 modified = 1; 483 in6->s6_addr16[1] = 0; 484 } 485 486 return modified; 487 } 488