Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/netinet6/in6_src.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 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: in6_src.c,v 1.132 2003/08/26 04:42:27 keiichi Exp $ 30 */ 31 32 /*- 33 * Copyright (c) 1982, 1986, 1991, 1993 34 * The Regents of the University of California. All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 4. Neither the name of the University nor the names of its contributors 45 * may be used to endorse or promote products derived from this software 46 * without specific prior written permission. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 * 60 * @(#)in_pcb.c 8.2 (Berkeley) 1/4/94 61 */ 62 63 #include <sys/cdefs.h> 64 __FBSDID("$FreeBSD: releng/6.4/sys/netinet6/in6_src.c 182649 2008-09-01 22:57:56Z obrien $"); 65 66 #include "opt_inet.h" 67 #include "opt_inet6.h" 68 69 #include <sys/param.h> 70 #include <sys/systm.h> 71 #include <sys/malloc.h> 72 #include <sys/mbuf.h> 73 #include <sys/protosw.h> 74 #include <sys/socket.h> 75 #include <sys/socketvar.h> 76 #include <sys/sockio.h> 77 #include <sys/sysctl.h> 78 #include <sys/errno.h> 79 #include <sys/time.h> 80 #include <sys/kernel.h> 81 #include <sys/lock.h> 82 #include <sys/sx.h> 83 84 #include <net/if.h> 85 #include <net/route.h> 86 87 #include <netinet/in.h> 88 #include <netinet/in_var.h> 89 #include <netinet/in_systm.h> 90 #include <netinet/ip.h> 91 #include <netinet/in_pcb.h> 92 #include <netinet6/in6_var.h> 93 #include <netinet/ip6.h> 94 #include <netinet6/in6_pcb.h> 95 #include <netinet6/ip6_var.h> 96 #include <netinet6/scope6_var.h> 97 #include <netinet6/nd6.h> 98 99 #include <net/net_osdep.h> 100 101 static struct mtx addrsel_lock; 102 #define ADDRSEL_LOCK_INIT() mtx_init(&addrsel_lock, "addrsel_lock", NULL, MTX_DEF) 103 #define ADDRSEL_LOCK() mtx_lock(&addrsel_lock) 104 #define ADDRSEL_UNLOCK() mtx_unlock(&addrsel_lock) 105 #define ADDRSEL_LOCK_ASSERT() mtx_assert(&addrsel_lock, MA_OWNED) 106 107 static struct sx addrsel_sxlock; 108 #define ADDRSEL_SXLOCK_INIT() sx_init(&addrsel_sxlock, "addrsel_sxlock") 109 #define ADDRSEL_SLOCK() sx_slock(&addrsel_sxlock) 110 #define ADDRSEL_SUNLOCK() sx_sunlock(&addrsel_sxlock) 111 #define ADDRSEL_XLOCK() sx_xlock(&addrsel_sxlock) 112 #define ADDRSEL_XUNLOCK() sx_xunlock(&addrsel_sxlock) 113 114 #define ADDR_LABEL_NOTAPP (-1) 115 struct in6_addrpolicy defaultaddrpolicy; 116 117 int ip6_prefer_tempaddr = 0; 118 119 static int selectroute __P((struct sockaddr_in6 *, struct ip6_pktopts *, 120 struct ip6_moptions *, struct route_in6 *, struct ifnet **, 121 struct rtentry **, int, int)); 122 static int in6_selectif __P((struct sockaddr_in6 *, struct ip6_pktopts *, 123 struct ip6_moptions *, struct route_in6 *ro, struct ifnet **)); 124 125 static struct in6_addrpolicy *lookup_addrsel_policy(struct sockaddr_in6 *); 126 127 static void init_policy_queue(void); 128 static int add_addrsel_policyent(struct in6_addrpolicy *); 129 static int delete_addrsel_policyent(struct in6_addrpolicy *); 130 static int walk_addrsel_policy __P((int (*)(struct in6_addrpolicy *, void *), 131 void *)); 132 static int dump_addrsel_policyent(struct in6_addrpolicy *, void *); 133 static struct in6_addrpolicy *match_addrsel_policy(struct sockaddr_in6 *); 134 135 /* 136 * Return an IPv6 address, which is the most appropriate for a given 137 * destination and user specified options. 138 * If necessary, this function lookups the routing table and returns 139 * an entry to the caller for later use. 140 */ 141 #define REPLACE(r) do {\ 142 if ((r) < sizeof(ip6stat.ip6s_sources_rule) / \ 143 sizeof(ip6stat.ip6s_sources_rule[0])) /* check for safety */ \ 144 ip6stat.ip6s_sources_rule[(r)]++; \ 145 /* printf("in6_selectsrc: replace %s with %s by %d\n", ia_best ? ip6_sprintf(&ia_best->ia_addr.sin6_addr) : "none", ip6_sprintf(&ia->ia_addr.sin6_addr), (r)); */ \ 146 goto replace; \ 147 } while(0) 148 #define NEXT(r) do {\ 149 if ((r) < sizeof(ip6stat.ip6s_sources_rule) / \ 150 sizeof(ip6stat.ip6s_sources_rule[0])) /* check for safety */ \ 151 ip6stat.ip6s_sources_rule[(r)]++; \ 152 /* printf("in6_selectsrc: keep %s against %s by %d\n", ia_best ? ip6_sprintf(&ia_best->ia_addr.sin6_addr) : "none", ip6_sprintf(&ia->ia_addr.sin6_addr), (r)); */ \ 153 goto next; /* XXX: we can't use 'continue' here */ \ 154 } while(0) 155 #define BREAK(r) do { \ 156 if ((r) < sizeof(ip6stat.ip6s_sources_rule) / \ 157 sizeof(ip6stat.ip6s_sources_rule[0])) /* check for safety */ \ 158 ip6stat.ip6s_sources_rule[(r)]++; \ 159 goto out; /* XXX: we can't use 'break' here */ \ 160 } while(0) 161 162 struct in6_addr * 163 in6_selectsrc(dstsock, opts, mopts, ro, laddr, ifpp, errorp) 164 struct sockaddr_in6 *dstsock; 165 struct ip6_pktopts *opts; 166 struct ip6_moptions *mopts; 167 struct route_in6 *ro; 168 struct in6_addr *laddr; 169 struct ifnet **ifpp; 170 int *errorp; 171 { 172 struct in6_addr dst; 173 struct ifnet *ifp = NULL; 174 struct in6_ifaddr *ia = NULL, *ia_best = NULL; 175 struct in6_pktinfo *pi = NULL; 176 int dst_scope = -1, best_scope = -1, best_matchlen = -1; 177 struct in6_addrpolicy *dst_policy = NULL, *best_policy = NULL; 178 u_int32_t odstzone; 179 int prefer_tempaddr; 180 181 dst = dstsock->sin6_addr; /* make a copy for local operation */ 182 *errorp = 0; 183 if (ifpp) 184 *ifpp = NULL; 185 186 /* 187 * If the source address is explicitly specified by the caller, 188 * check if the requested source address is indeed a unicast address 189 * assigned to the node, and can be used as the packet's source 190 * address. If everything is okay, use the address as source. 191 */ 192 if (opts && (pi = opts->ip6po_pktinfo) && 193 !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) { 194 struct sockaddr_in6 srcsock; 195 struct in6_ifaddr *ia6; 196 197 /* get the outgoing interface */ 198 if ((*errorp = in6_selectif(dstsock, opts, mopts, ro, &ifp)) 199 != 0) { 200 return (NULL); 201 } 202 203 /* 204 * determine the appropriate zone id of the source based on 205 * the zone of the destination and the outgoing interface. 206 * If the specified address is ambiguous wrt the scope zone, 207 * the interface must be specified; otherwise, ifa_ifwithaddr() 208 * will fail matching the address. 209 */ 210 bzero(&srcsock, sizeof(srcsock)); 211 srcsock.sin6_family = AF_INET6; 212 srcsock.sin6_len = sizeof(srcsock); 213 srcsock.sin6_addr = pi->ipi6_addr; 214 if (ifp) { 215 *errorp = in6_setscope(&srcsock.sin6_addr, ifp, NULL); 216 if (*errorp != 0) 217 return (NULL); 218 } 219 220 ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)(&srcsock)); 221 if (ia6 == NULL || 222 (ia6->ia6_flags & (IN6_IFF_ANYCAST | IN6_IFF_NOTREADY))) { 223 *errorp = EADDRNOTAVAIL; 224 return (NULL); 225 } 226 pi->ipi6_addr = srcsock.sin6_addr; /* XXX: this overrides pi */ 227 if (ifpp) 228 *ifpp = ifp; 229 return (&ia6->ia_addr.sin6_addr); 230 } 231 232 /* 233 * Otherwise, if the socket has already bound the source, just use it. 234 */ 235 if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr)) 236 return (laddr); 237 238 /* 239 * If the address is not specified, choose the best one based on 240 * the outgoing interface and the destination address. 241 */ 242 /* get the outgoing interface */ 243 if ((*errorp = in6_selectif(dstsock, opts, mopts, ro, &ifp)) != 0) 244 return (NULL); 245 246 #ifdef DIAGNOSTIC 247 if (ifp == NULL) /* this should not happen */ 248 panic("in6_selectsrc: NULL ifp"); 249 #endif 250 *errorp = in6_setscope(&dst, ifp, &odstzone); 251 if (*errorp != 0) 252 return (NULL); 253 254 for (ia = in6_ifaddr; ia; ia = ia->ia_next) { 255 int new_scope = -1, new_matchlen = -1; 256 struct in6_addrpolicy *new_policy = NULL; 257 u_int32_t srczone, osrczone, dstzone; 258 struct in6_addr src; 259 struct ifnet *ifp1 = ia->ia_ifp; 260 261 /* 262 * We'll never take an address that breaks the scope zone 263 * of the destination. We also skip an address if its zone 264 * does not contain the outgoing interface. 265 * XXX: we should probably use sin6_scope_id here. 266 */ 267 if (in6_setscope(&dst, ifp1, &dstzone) || 268 odstzone != dstzone) { 269 continue; 270 } 271 src = ia->ia_addr.sin6_addr; 272 if (in6_setscope(&src, ifp, &osrczone) || 273 in6_setscope(&src, ifp1, &srczone) || 274 osrczone != srczone) { 275 continue; 276 } 277 278 /* avoid unusable addresses */ 279 if ((ia->ia6_flags & 280 (IN6_IFF_NOTREADY | IN6_IFF_ANYCAST | IN6_IFF_DETACHED))) { 281 continue; 282 } 283 if (!ip6_use_deprecated && IFA6_IS_DEPRECATED(ia)) 284 continue; 285 286 /* Rule 1: Prefer same address */ 287 if (IN6_ARE_ADDR_EQUAL(&dst, &ia->ia_addr.sin6_addr)) { 288 ia_best = ia; 289 BREAK(1); /* there should be no better candidate */ 290 } 291 292 if (ia_best == NULL) 293 REPLACE(0); 294 295 /* Rule 2: Prefer appropriate scope */ 296 if (dst_scope < 0) 297 dst_scope = in6_addrscope(&dst); 298 new_scope = in6_addrscope(&ia->ia_addr.sin6_addr); 299 if (IN6_ARE_SCOPE_CMP(best_scope, new_scope) < 0) { 300 if (IN6_ARE_SCOPE_CMP(best_scope, dst_scope) < 0) 301 REPLACE(2); 302 NEXT(2); 303 } else if (IN6_ARE_SCOPE_CMP(new_scope, best_scope) < 0) { 304 if (IN6_ARE_SCOPE_CMP(new_scope, dst_scope) < 0) 305 NEXT(2); 306 REPLACE(2); 307 } 308 309 /* 310 * Rule 3: Avoid deprecated addresses. Note that the case of 311 * !ip6_use_deprecated is already rejected above. 312 */ 313 if (!IFA6_IS_DEPRECATED(ia_best) && IFA6_IS_DEPRECATED(ia)) 314 NEXT(3); 315 if (IFA6_IS_DEPRECATED(ia_best) && !IFA6_IS_DEPRECATED(ia)) 316 REPLACE(3); 317 318 /* Rule 4: Prefer home addresses */ 319 /* 320 * XXX: This is a TODO. We should probably merge the MIP6 321 * case above. 322 */ 323 324 /* Rule 5: Prefer outgoing interface */ 325 if (ia_best->ia_ifp == ifp && ia->ia_ifp != ifp) 326 NEXT(5); 327 if (ia_best->ia_ifp != ifp && ia->ia_ifp == ifp) 328 REPLACE(5); 329 330 /* 331 * Rule 6: Prefer matching label 332 * Note that best_policy should be non-NULL here. 333 */ 334 if (dst_policy == NULL) 335 dst_policy = lookup_addrsel_policy(dstsock); 336 if (dst_policy->label != ADDR_LABEL_NOTAPP) { 337 new_policy = lookup_addrsel_policy(&ia->ia_addr); 338 if (dst_policy->label == best_policy->label && 339 dst_policy->label != new_policy->label) 340 NEXT(6); 341 if (dst_policy->label != best_policy->label && 342 dst_policy->label == new_policy->label) 343 REPLACE(6); 344 } 345 346 /* 347 * Rule 7: Prefer public addresses. 348 * We allow users to reverse the logic by configuring 349 * a sysctl variable, so that privacy conscious users can 350 * always prefer temporary addresses. 351 */ 352 if (opts == NULL || 353 opts->ip6po_prefer_tempaddr == IP6PO_TEMPADDR_SYSTEM) { 354 prefer_tempaddr = ip6_prefer_tempaddr; 355 } else if (opts->ip6po_prefer_tempaddr == 356 IP6PO_TEMPADDR_NOTPREFER) { 357 prefer_tempaddr = 0; 358 } else 359 prefer_tempaddr = 1; 360 if (!(ia_best->ia6_flags & IN6_IFF_TEMPORARY) && 361 (ia->ia6_flags & IN6_IFF_TEMPORARY)) { 362 if (prefer_tempaddr) 363 REPLACE(7); 364 else 365 NEXT(7); 366 } 367 if ((ia_best->ia6_flags & IN6_IFF_TEMPORARY) && 368 !(ia->ia6_flags & IN6_IFF_TEMPORARY)) { 369 if (prefer_tempaddr) 370 NEXT(7); 371 else 372 REPLACE(7); 373 } 374 375 /* 376 * Rule 8: prefer addresses on alive interfaces. 377 * This is a KAME specific rule. 378 */ 379 if ((ia_best->ia_ifp->if_flags & IFF_UP) && 380 !(ia->ia_ifp->if_flags & IFF_UP)) 381 NEXT(8); 382 if (!(ia_best->ia_ifp->if_flags & IFF_UP) && 383 (ia->ia_ifp->if_flags & IFF_UP)) 384 REPLACE(8); 385 386 /* 387 * Rule 14: Use longest matching prefix. 388 * Note: in the address selection draft, this rule is 389 * documented as "Rule 8". However, since it is also 390 * documented that this rule can be overridden, we assign 391 * a large number so that it is easy to assign smaller numbers 392 * to more preferred rules. 393 */ 394 new_matchlen = in6_matchlen(&ia->ia_addr.sin6_addr, &dst); 395 if (best_matchlen < new_matchlen) 396 REPLACE(14); 397 if (new_matchlen < best_matchlen) 398 NEXT(14); 399 400 /* Rule 15 is reserved. */ 401 402 /* 403 * Last resort: just keep the current candidate. 404 * Or, do we need more rules? 405 */ 406 continue; 407 408 replace: 409 ia_best = ia; 410 best_scope = (new_scope >= 0 ? new_scope : 411 in6_addrscope(&ia_best->ia_addr.sin6_addr)); 412 best_policy = (new_policy ? new_policy : 413 lookup_addrsel_policy(&ia_best->ia_addr)); 414 best_matchlen = (new_matchlen >= 0 ? new_matchlen : 415 in6_matchlen(&ia_best->ia_addr.sin6_addr, 416 &dst)); 417 418 next: 419 continue; 420 421 out: 422 break; 423 } 424 425 if ((ia = ia_best) == NULL) { 426 *errorp = EADDRNOTAVAIL; 427 return (NULL); 428 } 429 430 if (ifpp) 431 *ifpp = ifp; 432 433 return (&ia->ia_addr.sin6_addr); 434 } 435 436 static int 437 selectroute(dstsock, opts, mopts, ro, retifp, retrt, clone, norouteok) 438 struct sockaddr_in6 *dstsock; 439 struct ip6_pktopts *opts; 440 struct ip6_moptions *mopts; 441 struct route_in6 *ro; 442 struct ifnet **retifp; 443 struct rtentry **retrt; 444 int clone; /* meaningful only for bsdi and freebsd. */ 445 int norouteok; 446 { 447 int error = 0; 448 struct ifnet *ifp = NULL; 449 struct rtentry *rt = NULL; 450 struct sockaddr_in6 *sin6_next; 451 struct in6_pktinfo *pi = NULL; 452 struct in6_addr *dst = &dstsock->sin6_addr; 453 454 #if 0 455 if (dstsock->sin6_addr.s6_addr32[0] == 0 && 456 dstsock->sin6_addr.s6_addr32[1] == 0 && 457 !IN6_IS_ADDR_LOOPBACK(&dstsock->sin6_addr)) { 458 printf("in6_selectroute: strange destination %s\n", 459 ip6_sprintf(&dstsock->sin6_addr)); 460 } else { 461 printf("in6_selectroute: destination = %s%%%d\n", 462 ip6_sprintf(&dstsock->sin6_addr), 463 dstsock->sin6_scope_id); /* for debug */ 464 } 465 #endif 466 467 /* If the caller specify the outgoing interface explicitly, use it. */ 468 if (opts && (pi = opts->ip6po_pktinfo) != NULL && pi->ipi6_ifindex) { 469 /* XXX boundary check is assumed to be already done. */ 470 ifp = ifnet_byindex(pi->ipi6_ifindex); 471 if (ifp != NULL && 472 (norouteok || retrt == NULL || 473 IN6_IS_ADDR_MULTICAST(dst))) { 474 /* 475 * we do not have to check or get the route for 476 * multicast. 477 */ 478 goto done; 479 } else 480 goto getroute; 481 } 482 483 /* 484 * If the destination address is a multicast address and the outgoing 485 * interface for the address is specified by the caller, use it. 486 */ 487 if (IN6_IS_ADDR_MULTICAST(dst) && 488 mopts != NULL && (ifp = mopts->im6o_multicast_ifp) != NULL) { 489 goto done; /* we do not need a route for multicast. */ 490 } 491 492 getroute: 493 /* 494 * If the next hop address for the packet is specified by the caller, 495 * use it as the gateway. 496 */ 497 if (opts && opts->ip6po_nexthop) { 498 struct route_in6 *ron; 499 500 sin6_next = satosin6(opts->ip6po_nexthop); 501 502 /* at this moment, we only support AF_INET6 next hops */ 503 if (sin6_next->sin6_family != AF_INET6) { 504 error = EAFNOSUPPORT; /* or should we proceed? */ 505 goto done; 506 } 507 508 /* 509 * If the next hop is an IPv6 address, then the node identified 510 * by that address must be a neighbor of the sending host. 511 */ 512 ron = &opts->ip6po_nextroute; 513 if ((ron->ro_rt && 514 (ron->ro_rt->rt_flags & (RTF_UP | RTF_LLINFO)) != 515 (RTF_UP | RTF_LLINFO)) || 516 !IN6_ARE_ADDR_EQUAL(&satosin6(&ron->ro_dst)->sin6_addr, 517 &sin6_next->sin6_addr)) { 518 if (ron->ro_rt) { 519 RTFREE(ron->ro_rt); 520 ron->ro_rt = NULL; 521 } 522 *satosin6(&ron->ro_dst) = *sin6_next; 523 } 524 if (ron->ro_rt == NULL) { 525 rtalloc((struct route *)ron); /* multi path case? */ 526 if (ron->ro_rt == NULL || 527 !(ron->ro_rt->rt_flags & RTF_LLINFO)) { 528 if (ron->ro_rt) { 529 RTFREE(ron->ro_rt); 530 ron->ro_rt = NULL; 531 } 532 error = EHOSTUNREACH; 533 goto done; 534 } 535 } 536 rt = ron->ro_rt; 537 ifp = rt->rt_ifp; 538 539 /* 540 * When cloning is required, try to allocate a route to the 541 * destination so that the caller can store path MTU 542 * information. 543 */ 544 if (!clone) 545 goto done; 546 } 547 548 /* 549 * Use a cached route if it exists and is valid, else try to allocate 550 * a new one. Note that we should check the address family of the 551 * cached destination, in case of sharing the cache with IPv4. 552 */ 553 if (ro) { 554 if (ro->ro_rt && 555 (!(ro->ro_rt->rt_flags & RTF_UP) || 556 ((struct sockaddr *)(&ro->ro_dst))->sa_family != AF_INET6 || 557 !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, 558 dst))) { 559 RTFREE(ro->ro_rt); 560 ro->ro_rt = (struct rtentry *)NULL; 561 } 562 if (ro->ro_rt == (struct rtentry *)NULL) { 563 struct sockaddr_in6 *sa6; 564 565 /* No route yet, so try to acquire one */ 566 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); 567 sa6 = (struct sockaddr_in6 *)&ro->ro_dst; 568 *sa6 = *dstsock; 569 sa6->sin6_scope_id = 0; 570 571 if (clone) { 572 rtalloc((struct route *)ro); 573 } else { 574 ro->ro_rt = rtalloc1(&((struct route *)ro) 575 ->ro_dst, 0, 0UL); 576 if (ro->ro_rt) 577 RT_UNLOCK(ro->ro_rt); 578 } 579 } 580 581 /* 582 * do not care about the result if we have the nexthop 583 * explicitly specified. 584 */ 585 if (opts && opts->ip6po_nexthop) 586 goto done; 587 588 if (ro->ro_rt) { 589 ifp = ro->ro_rt->rt_ifp; 590 591 if (ifp == NULL) { /* can this really happen? */ 592 RTFREE(ro->ro_rt); 593 ro->ro_rt = NULL; 594 } 595 } 596 if (ro->ro_rt == NULL) 597 error = EHOSTUNREACH; 598 rt = ro->ro_rt; 599 600 /* 601 * Check if the outgoing interface conflicts with 602 * the interface specified by ipi6_ifindex (if specified). 603 * Note that loopback interface is always okay. 604 * (this may happen when we are sending a packet to one of 605 * our own addresses.) 606 */ 607 if (ifp && opts && opts->ip6po_pktinfo && 608 opts->ip6po_pktinfo->ipi6_ifindex) { 609 if (!(ifp->if_flags & IFF_LOOPBACK) && 610 ifp->if_index != 611 opts->ip6po_pktinfo->ipi6_ifindex) { 612 error = EHOSTUNREACH; 613 goto done; 614 } 615 } 616 } 617 618 done: 619 if (ifp == NULL && rt == NULL) { 620 /* 621 * This can happen if the caller did not pass a cached route 622 * nor any other hints. We treat this case an error. 623 */ 624 error = EHOSTUNREACH; 625 } 626 if (error == EHOSTUNREACH) 627 ip6stat.ip6s_noroute++; 628 629 if (retifp != NULL) 630 *retifp = ifp; 631 if (retrt != NULL) 632 *retrt = rt; /* rt may be NULL */ 633 634 return (error); 635 } 636 637 static int 638 in6_selectif(dstsock, opts, mopts, ro, retifp) 639 struct sockaddr_in6 *dstsock; 640 struct ip6_pktopts *opts; 641 struct ip6_moptions *mopts; 642 struct route_in6 *ro; 643 struct ifnet **retifp; 644 { 645 int error; 646 struct route_in6 sro; 647 struct rtentry *rt = NULL; 648 649 if (ro == NULL) { 650 bzero(&sro, sizeof(sro)); 651 ro = &sro; 652 } 653 654 if ((error = selectroute(dstsock, opts, mopts, ro, retifp, 655 &rt, 0, 1)) != 0) { 656 if (rt && rt == sro.ro_rt) 657 RTFREE(rt); 658 return (error); 659 } 660 661 /* 662 * do not use a rejected or black hole route. 663 * XXX: this check should be done in the L2 output routine. 664 * However, if we skipped this check here, we'd see the following 665 * scenario: 666 * - install a rejected route for a scoped address prefix 667 * (like fe80::/10) 668 * - send a packet to a destination that matches the scoped prefix, 669 * with ambiguity about the scope zone. 670 * - pick the outgoing interface from the route, and disambiguate the 671 * scope zone with the interface. 672 * - ip6_output() would try to get another route with the "new" 673 * destination, which may be valid. 674 * - we'd see no error on output. 675 * Although this may not be very harmful, it should still be confusing. 676 * We thus reject the case here. 677 */ 678 if (rt && (rt->rt_flags & (RTF_REJECT | RTF_BLACKHOLE))) { 679 int flags = (rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 680 681 if (rt && rt == sro.ro_rt) 682 RTFREE(rt); 683 return (flags); 684 } 685 686 /* 687 * Adjust the "outgoing" interface. If we're going to loop the packet 688 * back to ourselves, the ifp would be the loopback interface. 689 * However, we'd rather know the interface associated to the 690 * destination address (which should probably be one of our own 691 * addresses.) 692 */ 693 if (rt && rt->rt_ifa && rt->rt_ifa->ifa_ifp) 694 *retifp = rt->rt_ifa->ifa_ifp; 695 696 if (rt && rt == sro.ro_rt) 697 RTFREE(rt); 698 return (0); 699 } 700 701 int 702 in6_selectroute(dstsock, opts, mopts, ro, retifp, retrt, clone) 703 struct sockaddr_in6 *dstsock; 704 struct ip6_pktopts *opts; 705 struct ip6_moptions *mopts; 706 struct route_in6 *ro; 707 struct ifnet **retifp; 708 struct rtentry **retrt; 709 int clone; /* meaningful only for bsdi and freebsd. */ 710 { 711 return (selectroute(dstsock, opts, mopts, ro, retifp, 712 retrt, clone, 0)); 713 } 714 715 /* 716 * Default hop limit selection. The precedence is as follows: 717 * 1. Hoplimit value specified via ioctl. 718 * 2. (If the outgoing interface is detected) the current 719 * hop limit of the interface specified by router advertisement. 720 * 3. The system default hoplimit. 721 */ 722 int 723 in6_selecthlim(in6p, ifp) 724 struct in6pcb *in6p; 725 struct ifnet *ifp; 726 { 727 if (in6p && in6p->in6p_hops >= 0) 728 return (in6p->in6p_hops); 729 else if (ifp) 730 return (ND_IFINFO(ifp)->chlim); 731 else if (in6p && !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) { 732 struct route_in6 ro6; 733 struct ifnet *lifp; 734 735 bzero(&ro6, sizeof(ro6)); 736 ro6.ro_dst.sin6_family = AF_INET6; 737 ro6.ro_dst.sin6_len = sizeof(struct sockaddr_in6); 738 ro6.ro_dst.sin6_addr = in6p->in6p_faddr; 739 rtalloc((struct route *)&ro6); 740 if (ro6.ro_rt) { 741 lifp = ro6.ro_rt->rt_ifp; 742 RTFREE(ro6.ro_rt); 743 if (lifp) 744 return (ND_IFINFO(lifp)->chlim); 745 } else 746 return (ip6_defhlim); 747 } 748 return (ip6_defhlim); 749 } 750 751 /* 752 * XXX: this is borrowed from in6_pcbbind(). If possible, we should 753 * share this function by all *bsd*... 754 */ 755 int 756 in6_pcbsetport(laddr, inp, cred) 757 struct in6_addr *laddr; 758 struct inpcb *inp; 759 struct ucred *cred; 760 { 761 struct socket *so = inp->inp_socket; 762 u_int16_t lport = 0, first, last, *lastport; 763 int count, error = 0, wild = 0; 764 struct inpcbinfo *pcbinfo = inp->inp_pcbinfo; 765 766 /* XXX: this is redundant when called from in6_pcbbind */ 767 if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0) 768 wild = INPLOOKUP_WILDCARD; 769 770 inp->inp_flags |= INP_ANONPORT; 771 772 if (inp->inp_flags & INP_HIGHPORT) { 773 first = ipport_hifirstauto; /* sysctl */ 774 last = ipport_hilastauto; 775 lastport = &pcbinfo->lasthi; 776 } else if (inp->inp_flags & INP_LOWPORT) { 777 if ((error = suser_cred(cred, 0))) 778 return error; 779 first = ipport_lowfirstauto; /* 1023 */ 780 last = ipport_lowlastauto; /* 600 */ 781 lastport = &pcbinfo->lastlow; 782 } else { 783 first = ipport_firstauto; /* sysctl */ 784 last = ipport_lastauto; 785 lastport = &pcbinfo->lastport; 786 } 787 /* 788 * Simple check to ensure all ports are not used up causing 789 * a deadlock here. 790 * 791 * We split the two cases (up and down) so that the direction 792 * is not being tested on each round of the loop. 793 */ 794 if (first > last) { 795 /* 796 * counting down 797 */ 798 count = first - last; 799 800 do { 801 if (count-- < 0) { /* completely used? */ 802 /* 803 * Undo any address bind that may have 804 * occurred above. 805 */ 806 inp->in6p_laddr = in6addr_any; 807 return (EAGAIN); 808 } 809 --*lastport; 810 if (*lastport > first || *lastport < last) 811 *lastport = first; 812 lport = htons(*lastport); 813 } while (in6_pcblookup_local(pcbinfo, &inp->in6p_laddr, 814 lport, wild)); 815 } else { 816 /* 817 * counting up 818 */ 819 count = last - first; 820 821 do { 822 if (count-- < 0) { /* completely used? */ 823 /* 824 * Undo any address bind that may have 825 * occurred above. 826 */ 827 inp->in6p_laddr = in6addr_any; 828 return (EAGAIN); 829 } 830 ++*lastport; 831 if (*lastport < first || *lastport > last) 832 *lastport = first; 833 lport = htons(*lastport); 834 } while (in6_pcblookup_local(pcbinfo, 835 &inp->in6p_laddr, lport, wild)); 836 } 837 838 inp->inp_lport = lport; 839 if (in_pcbinshash(inp) != 0) { 840 inp->in6p_laddr = in6addr_any; 841 inp->inp_lport = 0; 842 return (EAGAIN); 843 } 844 845 return (0); 846 } 847 848 void 849 addrsel_policy_init() 850 { 851 ADDRSEL_LOCK_INIT(); 852 ADDRSEL_SXLOCK_INIT(); 853 854 init_policy_queue(); 855 856 /* initialize the "last resort" policy */ 857 bzero(&defaultaddrpolicy, sizeof(defaultaddrpolicy)); 858 defaultaddrpolicy.label = ADDR_LABEL_NOTAPP; 859 } 860 861 static struct in6_addrpolicy * 862 lookup_addrsel_policy(key) 863 struct sockaddr_in6 *key; 864 { 865 struct in6_addrpolicy *match = NULL; 866 867 ADDRSEL_LOCK(); 868 match = match_addrsel_policy(key); 869 870 if (match == NULL) 871 match = &defaultaddrpolicy; 872 else 873 match->use++; 874 ADDRSEL_UNLOCK(); 875 876 return (match); 877 } 878 879 /* 880 * Subroutines to manage the address selection policy table via sysctl. 881 */ 882 struct walkarg { 883 struct sysctl_req *w_req; 884 }; 885 886 static int in6_src_sysctl(SYSCTL_HANDLER_ARGS); 887 SYSCTL_DECL(_net_inet6_ip6); 888 SYSCTL_NODE(_net_inet6_ip6, IPV6CTL_ADDRCTLPOLICY, addrctlpolicy, 889 CTLFLAG_RD, in6_src_sysctl, ""); 890 891 static int 892 in6_src_sysctl(SYSCTL_HANDLER_ARGS) 893 { 894 struct walkarg w; 895 896 if (req->newptr) 897 return EPERM; 898 899 bzero(&w, sizeof(w)); 900 w.w_req = req; 901 902 return (walk_addrsel_policy(dump_addrsel_policyent, &w)); 903 } 904 905 int 906 in6_src_ioctl(cmd, data) 907 u_long cmd; 908 caddr_t data; 909 { 910 int i; 911 struct in6_addrpolicy ent0; 912 913 if (cmd != SIOCAADDRCTL_POLICY && cmd != SIOCDADDRCTL_POLICY) 914 return (EOPNOTSUPP); /* check for safety */ 915 916 ent0 = *(struct in6_addrpolicy *)data; 917 918 if (ent0.label == ADDR_LABEL_NOTAPP) 919 return (EINVAL); 920 /* check if the prefix mask is consecutive. */ 921 if (in6_mask2len(&ent0.addrmask.sin6_addr, NULL) < 0) 922 return (EINVAL); 923 /* clear trailing garbages (if any) of the prefix address. */ 924 for (i = 0; i < 4; i++) { 925 ent0.addr.sin6_addr.s6_addr32[i] &= 926 ent0.addrmask.sin6_addr.s6_addr32[i]; 927 } 928 ent0.use = 0; 929 930 switch (cmd) { 931 case SIOCAADDRCTL_POLICY: 932 return (add_addrsel_policyent(&ent0)); 933 case SIOCDADDRCTL_POLICY: 934 return (delete_addrsel_policyent(&ent0)); 935 } 936 937 return (0); /* XXX: compromise compilers */ 938 } 939 940 /* 941 * The followings are implementation of the policy table using a 942 * simple tail queue. 943 * XXX such details should be hidden. 944 * XXX implementation using binary tree should be more efficient. 945 */ 946 struct addrsel_policyent { 947 TAILQ_ENTRY(addrsel_policyent) ape_entry; 948 struct in6_addrpolicy ape_policy; 949 }; 950 951 TAILQ_HEAD(addrsel_policyhead, addrsel_policyent); 952 953 struct addrsel_policyhead addrsel_policytab; 954 955 static void 956 init_policy_queue() 957 { 958 TAILQ_INIT(&addrsel_policytab); 959 } 960 961 static int 962 add_addrsel_policyent(newpolicy) 963 struct in6_addrpolicy *newpolicy; 964 { 965 struct addrsel_policyent *new, *pol; 966 967 MALLOC(new, struct addrsel_policyent *, sizeof(*new), M_IFADDR, 968 M_WAITOK); 969 ADDRSEL_XLOCK(); 970 ADDRSEL_LOCK(); 971 972 /* duplication check */ 973 TAILQ_FOREACH(pol, &addrsel_policytab, ape_entry) { 974 if (IN6_ARE_ADDR_EQUAL(&newpolicy->addr.sin6_addr, 975 &pol->ape_policy.addr.sin6_addr) && 976 IN6_ARE_ADDR_EQUAL(&newpolicy->addrmask.sin6_addr, 977 &pol->ape_policy.addrmask.sin6_addr)) { 978 ADDRSEL_UNLOCK(); 979 ADDRSEL_XUNLOCK(); 980 FREE(new, M_IFADDR); 981 return (EEXIST); /* or override it? */ 982 } 983 } 984 985 bzero(new, sizeof(*new)); 986 987 /* XXX: should validate entry */ 988 new->ape_policy = *newpolicy; 989 990 TAILQ_INSERT_TAIL(&addrsel_policytab, new, ape_entry); 991 ADDRSEL_UNLOCK(); 992 ADDRSEL_XUNLOCK(); 993 994 return (0); 995 } 996 997 static int 998 delete_addrsel_policyent(key) 999 struct in6_addrpolicy *key; 1000 { 1001 struct addrsel_policyent *pol; 1002 1003 ADDRSEL_XLOCK(); 1004 ADDRSEL_LOCK(); 1005 1006 /* search for the entry in the table */ 1007 TAILQ_FOREACH(pol, &addrsel_policytab, ape_entry) { 1008 if (IN6_ARE_ADDR_EQUAL(&key->addr.sin6_addr, 1009 &pol->ape_policy.addr.sin6_addr) && 1010 IN6_ARE_ADDR_EQUAL(&key->addrmask.sin6_addr, 1011 &pol->ape_policy.addrmask.sin6_addr)) { 1012 break; 1013 } 1014 } 1015 if (pol == NULL) { 1016 ADDRSEL_UNLOCK(); 1017 ADDRSEL_XUNLOCK(); 1018 return (ESRCH); 1019 } 1020 1021 TAILQ_REMOVE(&addrsel_policytab, pol, ape_entry); 1022 ADDRSEL_UNLOCK(); 1023 ADDRSEL_XUNLOCK(); 1024 1025 return (0); 1026 } 1027 1028 static int 1029 walk_addrsel_policy(int (*callback)(struct in6_addrpolicy *, void *), void *w) 1030 { 1031 struct addrsel_policyent *pol; 1032 int error = 0; 1033 1034 ADDRSEL_SLOCK(); 1035 TAILQ_FOREACH(pol, &addrsel_policytab, ape_entry) { 1036 if ((error = (*callback)(&pol->ape_policy, w)) != 0) { 1037 ADDRSEL_SUNLOCK(); 1038 return (error); 1039 } 1040 } 1041 ADDRSEL_SUNLOCK(); 1042 return (error); 1043 } 1044 1045 static int 1046 dump_addrsel_policyent(pol, arg) 1047 struct in6_addrpolicy *pol; 1048 void *arg; 1049 { 1050 int error = 0; 1051 struct walkarg *w = arg; 1052 1053 error = SYSCTL_OUT(w->w_req, pol, sizeof(*pol)); 1054 1055 return (error); 1056 } 1057 1058 static struct in6_addrpolicy * 1059 match_addrsel_policy(key) 1060 struct sockaddr_in6 *key; 1061 { 1062 struct addrsel_policyent *pent; 1063 struct in6_addrpolicy *bestpol = NULL, *pol; 1064 int matchlen, bestmatchlen = -1; 1065 u_char *mp, *ep, *k, *p, m; 1066 1067 TAILQ_FOREACH(pent, &addrsel_policytab, ape_entry) { 1068 matchlen = 0; 1069 1070 pol = &pent->ape_policy; 1071 mp = (u_char *)&pol->addrmask.sin6_addr; 1072 ep = mp + 16; /* XXX: scope field? */ 1073 k = (u_char *)&key->sin6_addr; 1074 p = (u_char *)&pol->addr.sin6_addr; 1075 for (; mp < ep && *mp; mp++, k++, p++) { 1076 m = *mp; 1077 if ((*k & m) != *p) 1078 goto next; /* not match */ 1079 if (m == 0xff) /* short cut for a typical case */ 1080 matchlen += 8; 1081 else { 1082 while (m >= 0x80) { 1083 matchlen++; 1084 m <<= 1; 1085 } 1086 } 1087 } 1088 1089 /* matched. check if this is better than the current best. */ 1090 if (bestpol == NULL || 1091 matchlen > bestmatchlen) { 1092 bestpol = pol; 1093 bestmatchlen = matchlen; 1094 } 1095 1096 next: 1097 continue; 1098 } 1099 1100 return (bestpol); 1101 }
Cache object: d7e05c4b5bab85cddd447871a766eaf7
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]