1 /* $FreeBSD: src/sys/netinet6/in6_src.c,v 1.1.2.3 2002/02/26 18:02:06 ume Exp $ */ 2 /* $KAME: in6_src.c,v 1.37 2001/03/29 05:34:31 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 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 /* 34 * Copyright (c) 1982, 1986, 1991, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)in_pcb.c 8.2 (Berkeley) 1/4/94 62 */ 63 64 #include "opt_inet.h" 65 #include "opt_inet6.h" 66 67 #include <sys/param.h> 68 #include <sys/systm.h> 69 #include <sys/jail.h> 70 #include <sys/kernel.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/proc.h> 81 #include <sys/caps.h> 82 83 #include <net/if.h> 84 #include <net/route.h> 85 86 #include <netinet/in.h> 87 #include <netinet/in_var.h> 88 #include <netinet/in_systm.h> 89 #include <netinet/ip.h> 90 #include <netinet/in_pcb.h> 91 #include <netinet6/in6_var.h> 92 #include <netinet/ip6.h> 93 #include <netinet6/in6_pcb.h> 94 #include <netinet6/ip6_var.h> 95 #include <netinet6/nd6.h> 96 #ifdef ENABLE_DEFAULT_SCOPE 97 #include <netinet6/scope6_var.h> 98 #endif 99 100 #include <net/net_osdep.h> 101 102 #define ADDR_LABEL_NOTAPP (-1) 103 struct in6_addrpolicy defaultaddrpolicy; 104 105 static void init_policy_queue(void); 106 static int add_addrsel_policyent(struct in6_addrpolicy *); 107 static int delete_addrsel_policyent(struct in6_addrpolicy *); 108 static int walk_addrsel_policy(int (*)(struct in6_addrpolicy *, void *), 109 void *); 110 static int dump_addrsel_policyent(struct in6_addrpolicy *, void *); 111 112 113 /* 114 * Return an IPv6 address, which is the most appropriate for a given 115 * destination and user specified options. 116 * If necessary, this function lookups the routing table and returns 117 * an entry to the caller for later use. 118 */ 119 struct in6_addr * 120 in6_selectsrc(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, 121 struct ip6_moptions *mopts, struct route_in6 *ro, 122 struct in6_addr *laddr, int *errorp, struct thread *td) 123 { 124 struct sockaddr_in6 jsin6; 125 struct ucred *cred = NULL; 126 struct in6_addr *dst; 127 struct in6_ifaddr *ia6 = NULL; 128 struct in6_pktinfo *pi = NULL; 129 int jailed = 0; 130 131 if (td && td->td_proc && td->td_proc->p_ucred) 132 cred = td->td_proc->p_ucred; 133 if (cred && cred->cr_prison) 134 jailed = 1; 135 jsin6.sin6_family = AF_INET6; 136 dst = &dstsock->sin6_addr; 137 *errorp = 0; 138 139 /* 140 * If the source address is explicitly specified by the caller, 141 * use it. 142 */ 143 if (opts && (pi = opts->ip6po_pktinfo) && 144 !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) { 145 jsin6.sin6_addr = pi->ipi6_addr; 146 if (jailed && !jailed_ip(cred->cr_prison, 147 (struct sockaddr *)&jsin6)) { 148 return(0); 149 } else { 150 return (&pi->ipi6_addr); 151 } 152 } 153 154 /* 155 * If the source address is not specified but the socket(if any) 156 * is already bound, use the bound address. 157 */ 158 if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr)) { 159 jsin6.sin6_addr = *laddr; 160 if (jailed && !jailed_ip(cred->cr_prison, 161 (struct sockaddr *)&jsin6)) { 162 return(0); 163 } else { 164 return (laddr); 165 } 166 } 167 168 /* 169 * If the caller doesn't specify the source address but 170 * the outgoing interface, use an address associated with 171 * the interface. 172 */ 173 if (pi && pi->ipi6_ifindex) { 174 /* XXX boundary check is assumed to be already done. */ 175 ia6 = in6_ifawithscope(ifindex2ifnet[pi->ipi6_ifindex], 176 dst, cred); 177 178 if (ia6 && jailed) { 179 jsin6.sin6_addr = (&ia6->ia_addr)->sin6_addr; 180 if (!jailed_ip(cred->cr_prison, 181 (struct sockaddr *)&jsin6)) 182 ia6 = NULL; 183 } 184 185 if (ia6 == NULL) { 186 *errorp = EADDRNOTAVAIL; 187 return (0); 188 } 189 return (&satosin6(&ia6->ia_addr)->sin6_addr); 190 } 191 192 /* 193 * If the destination address is a link-local unicast address or 194 * a multicast address, and if the outgoing interface is specified 195 * by the sin6_scope_id filed, use an address associated with the 196 * interface. 197 * XXX: We're now trying to define more specific semantics of 198 * sin6_scope_id field, so this part will be rewritten in 199 * the near future. 200 */ 201 if ((IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MULTICAST(dst)) && 202 dstsock->sin6_scope_id) { 203 /* 204 * I'm not sure if boundary check for scope_id is done 205 * somewhere... 206 */ 207 if (dstsock->sin6_scope_id < 0 || 208 if_index < dstsock->sin6_scope_id) { 209 *errorp = ENXIO; /* XXX: better error? */ 210 return (0); 211 } 212 ia6 = in6_ifawithscope(ifindex2ifnet[dstsock->sin6_scope_id], 213 dst, cred); 214 215 if (ia6 && jailed) { 216 jsin6.sin6_addr = (&ia6->ia_addr)->sin6_addr; 217 if (!jailed_ip(cred->cr_prison, 218 (struct sockaddr *)&jsin6)) 219 ia6 = NULL; 220 } 221 222 if (ia6 == NULL) { 223 *errorp = EADDRNOTAVAIL; 224 return (0); 225 } 226 return (&satosin6(&ia6->ia_addr)->sin6_addr); 227 } 228 229 /* 230 * If the destination address is a multicast address and 231 * the outgoing interface for the address is specified 232 * by the caller, use an address associated with the interface. 233 * There is a sanity check here; if the destination has node-local 234 * scope, the outgoing interfacde should be a loopback address. 235 * Even if the outgoing interface is not specified, we also 236 * choose a loopback interface as the outgoing interface. 237 */ 238 if (!jailed && IN6_IS_ADDR_MULTICAST(dst)) { 239 struct ifnet *ifp = mopts ? mopts->im6o_multicast_ifp : NULL; 240 241 if (ifp == NULL && IN6_IS_ADDR_MC_INTFACELOCAL(dst)) { 242 ifp = loif; 243 } 244 245 if (ifp) { 246 ia6 = in6_ifawithscope(ifp, dst, cred); 247 if (ia6 == NULL) { 248 *errorp = EADDRNOTAVAIL; 249 return (0); 250 } 251 return (&satosin6(&ia6->ia_addr)->sin6_addr); 252 } 253 } 254 255 /* 256 * If the next hop address for the packet is specified 257 * by caller, use an address associated with the route 258 * to the next hop. 259 */ 260 { 261 struct sockaddr_in6 *sin6_next; 262 struct rtentry *rt; 263 264 if (opts && opts->ip6po_nexthop) { 265 sin6_next = satosin6(opts->ip6po_nexthop); 266 rt = nd6_lookup(&sin6_next->sin6_addr, 1, NULL); 267 if (rt) { 268 ia6 = in6_ifawithscope(rt->rt_ifp, dst, cred); 269 if (ia6 == NULL) 270 ia6 = ifatoia6(rt->rt_ifa); 271 } 272 if (ia6 && jailed) { 273 jsin6.sin6_addr = (&ia6->ia_addr)->sin6_addr; 274 if (!jailed_ip(cred->cr_prison, 275 (struct sockaddr *)&jsin6)) 276 ia6 = NULL; 277 } 278 279 if (ia6 == NULL) { 280 *errorp = EADDRNOTAVAIL; 281 return (0); 282 } 283 return (&satosin6(&ia6->ia_addr)->sin6_addr); 284 } 285 } 286 287 /* 288 * If route is known or can be allocated now, 289 * our src addr is taken from the i/f, else punt. 290 */ 291 if (ro) { 292 if (ro->ro_rt && 293 (!(ro->ro_rt->rt_flags & RTF_UP) || 294 satosin6(&ro->ro_dst)->sin6_family != AF_INET6 || 295 !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, 296 dst))) { 297 RTFREE(ro->ro_rt); 298 ro->ro_rt = NULL; 299 } 300 if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp == NULL) { 301 struct sockaddr_in6 *sa6; 302 303 /* No route yet, so try to acquire one */ 304 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); 305 sa6 = &ro->ro_dst; 306 sa6->sin6_family = AF_INET6; 307 sa6->sin6_len = sizeof(struct sockaddr_in6); 308 sa6->sin6_addr = *dst; 309 sa6->sin6_scope_id = dstsock->sin6_scope_id; 310 if (!jailed && IN6_IS_ADDR_MULTICAST(dst)) { 311 ro->ro_rt = 312 rtpurelookup((struct sockaddr *)&ro->ro_dst); 313 } else { 314 rtalloc((struct route *)ro); 315 } 316 } 317 318 /* 319 * in_pcbconnect() checks out IFF_LOOPBACK to skip using 320 * the address. But we don't know why it does so. 321 * It is necessary to ensure the scope even for lo0 322 * so doesn't check out IFF_LOOPBACK. 323 */ 324 325 if (ro->ro_rt) { 326 ia6 = in6_ifawithscope(ro->ro_rt->rt_ifa->ifa_ifp, dst, cred); 327 if (ia6 && jailed) { 328 jsin6.sin6_addr = (&ia6->ia_addr)->sin6_addr; 329 if (!jailed_ip(cred->cr_prison, 330 (struct sockaddr *)&jsin6)) 331 ia6 = NULL; 332 } 333 334 if (ia6 == NULL) /* xxx scope error ?*/ 335 ia6 = ifatoia6(ro->ro_rt->rt_ifa); 336 337 if (ia6 && jailed) { 338 jsin6.sin6_addr = (&ia6->ia_addr)->sin6_addr; 339 if (!jailed_ip(cred->cr_prison, 340 (struct sockaddr *)&jsin6)) 341 ia6 = NULL; 342 } 343 } 344 if (ia6 == NULL) { 345 *errorp = EHOSTUNREACH; /* no route */ 346 return (0); 347 } 348 return (&satosin6(&ia6->ia_addr)->sin6_addr); 349 } 350 351 *errorp = EADDRNOTAVAIL; 352 return (0); 353 } 354 355 /* 356 * Default hop limit selection. The precedence is as follows: 357 * 1. Hoplimit value specified via ioctl. 358 * 2. (If the outgoing interface is detected) the current 359 * hop limit of the interface specified by router advertisement. 360 * 3. The system default hoplimit. 361 */ 362 int 363 in6_selecthlim(struct in6pcb *in6p, struct ifnet *ifp) 364 { 365 int hlim; 366 367 if (in6p && in6p->in6p_hops >= 0) { 368 return (in6p->in6p_hops); 369 } else if (ifp) { 370 hlim = ND_IFINFO(ifp)->chlim; 371 if (hlim < ip6_minhlim) 372 hlim = ip6_minhlim; 373 } else { 374 hlim = ip6_defhlim; 375 } 376 return (hlim); 377 } 378 379 static boolean_t 380 in6_pcbporthash_update(struct inpcbportinfo *portinfo, 381 struct inpcb *inp, u_short lport, struct ucred *cred, int wild) 382 { 383 struct inpcbporthead *porthash; 384 385 /* 386 * This has to be atomic. If the porthash is shared across multiple 387 * protocol threads, e.g. tcp and udp, then the token must be held. 388 */ 389 porthash = in_pcbporthash_head(portinfo, lport); 390 GET_PORTHASH_TOKEN(porthash); 391 392 if (in6_pcblookup_local(porthash, &inp->in6p_laddr, lport, 393 wild, cred) != NULL) { 394 REL_PORTHASH_TOKEN(porthash); 395 return FALSE; 396 } 397 inp->inp_lport = lport; 398 in_pcbinsporthash(porthash, inp); 399 400 REL_PORTHASH_TOKEN(porthash); 401 return TRUE; 402 } 403 404 /* 405 * XXX: this is borrowed from in6_pcbbind(). If possible, we should 406 * share this function by all *bsd*... 407 */ 408 int 409 in6_pcbsetlport(struct in6_addr *laddr, struct inpcb *inp, struct thread *td) 410 { 411 struct socket *so = inp->inp_socket; 412 uint16_t lport, first, last, step, first0, last0; 413 int count, error = 0, wild = 0; 414 struct inpcbinfo *pcbinfo = inp->inp_pcbinfo; 415 struct inpcbportinfo *portinfo; 416 struct ucred *cred = NULL; 417 int portinfo_first, portinfo_idx; 418 uint32_t cut; 419 420 /* XXX: this is redundant when called from in6_pcbbind */ 421 if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0) 422 wild = INPLOOKUP_WILDCARD; 423 if (td->td_proc && td->td_proc->p_ucred) 424 cred = td->td_proc->p_ucred; 425 426 inp->inp_flags |= INP_ANONPORT; 427 428 step = pcbinfo->portinfo_cnt; 429 portinfo_first = mycpuid % pcbinfo->portinfo_cnt; 430 portinfo_idx = portinfo_first; 431 432 if (inp->inp_flags & INP_HIGHPORT) { 433 first0 = ipport_hifirstauto; /* sysctl */ 434 last0 = ipport_hilastauto; 435 } else if (inp->inp_flags & INP_LOWPORT) { 436 error = caps_priv_check_td(td, SYSCAP_RESTRICTEDROOT); 437 if (error) 438 return error; 439 first0 = ipport_lowfirstauto; /* 1023 */ 440 last0 = ipport_lowlastauto; /* 600 */ 441 } else { 442 first0 = ipport_firstauto; /* sysctl */ 443 last0 = ipport_lastauto; 444 } 445 if (first0 > last0) { 446 lport = last0; 447 last0 = first0; 448 first0 = lport; 449 } 450 KKASSERT(last0 >= first0); 451 452 cut = karc4random(); 453 loop: 454 portinfo = &pcbinfo->portinfo[portinfo_idx]; 455 first = first0; 456 last = last0; 457 458 /* 459 * Simple check to ensure all ports are not used up causing 460 * a deadlock here. 461 */ 462 in_pcbportrange(&last, &first, portinfo->offset, step); 463 lport = last - first; 464 count = lport / step; 465 466 lport = rounddown(cut % lport, step) + first; 467 KKASSERT(lport % step == portinfo->offset); 468 469 for (;;) { 470 if (count-- < 0) { /* completely used? */ 471 error = EAGAIN; 472 break; 473 } 474 475 if (__predict_false(lport < first || lport > last)) { 476 lport = first; 477 KKASSERT(lport % step == portinfo->offset); 478 } 479 480 if (in6_pcbporthash_update(portinfo, inp, htons(lport), 481 cred, wild)) { 482 error = 0; 483 break; 484 } 485 486 lport += step; 487 KKASSERT(lport % step == portinfo->offset); 488 } 489 490 if (error) { 491 /* Try next portinfo */ 492 portinfo_idx++; 493 portinfo_idx %= pcbinfo->portinfo_cnt; 494 if (portinfo_idx != portinfo_first) 495 goto loop; 496 497 /* Undo any address bind that may have occurred above. */ 498 inp->in6p_laddr = kin6addr_any; 499 } 500 return error; 501 } 502 503 /* 504 * Generate kernel-internal form (scopeid embedded into s6_addr16[1]). 505 * If the address scope of is link-local, embed the interface index in the 506 * address. The routine determines our precedence 507 * between advanced API scope/interface specification and basic API 508 * specification. 509 * 510 * This function should be nuked in the future, when we get rid of embedded 511 * scopeid thing. 512 * 513 * XXX actually, it is over-specification to return ifp against sin6_scope_id. 514 * there can be multiple interfaces that belong to a particular scope zone 515 * (in specification, we have 1:N mapping between a scope zone and interfaces). 516 * we may want to change the function to return something other than ifp. 517 */ 518 int 519 in6_embedscope(struct in6_addr *in6, 520 const struct sockaddr_in6 *sin6, 521 #ifdef HAVE_NRL_INPCB 522 struct inpcb *in6p, 523 #define in6p_outputopts inp_outputopts6 524 #define in6p_moptions inp_moptions6 525 #else 526 struct in6pcb *in6p, 527 #endif 528 struct ifnet **ifpp) 529 { 530 struct ifnet *ifp = NULL; 531 u_int32_t scopeid; 532 533 *in6 = sin6->sin6_addr; 534 scopeid = sin6->sin6_scope_id; 535 if (ifpp) 536 *ifpp = NULL; 537 538 /* 539 * don't try to read sin6->sin6_addr beyond here, since the caller may 540 * ask us to overwrite existing sockaddr_in6 541 */ 542 543 #ifdef ENABLE_DEFAULT_SCOPE 544 if (scopeid == 0) 545 scopeid = scope6_addr2default(in6); 546 #endif 547 548 if (IN6_IS_SCOPE_LINKLOCAL(in6)) { 549 struct in6_pktinfo *pi; 550 551 /* 552 * KAME assumption: link id == interface id 553 */ 554 555 if (in6p && in6p->in6p_outputopts && 556 (pi = in6p->in6p_outputopts->ip6po_pktinfo) && 557 pi->ipi6_ifindex) { 558 ifp = ifindex2ifnet[pi->ipi6_ifindex]; 559 in6->s6_addr16[1] = htons(pi->ipi6_ifindex); 560 } else if (in6p && IN6_IS_ADDR_MULTICAST(in6) && 561 in6p->in6p_moptions && 562 in6p->in6p_moptions->im6o_multicast_ifp) { 563 ifp = in6p->in6p_moptions->im6o_multicast_ifp; 564 in6->s6_addr16[1] = htons(ifp->if_index); 565 } else if (scopeid) { 566 /* boundary check */ 567 if (scopeid < 0 || if_index < scopeid) 568 return ENXIO; /* XXX EINVAL? */ 569 ifp = ifindex2ifnet[scopeid]; 570 /* XXX assignment to 16bit from 32bit variable */ 571 in6->s6_addr16[1] = htons(scopeid & 0xffff); 572 } 573 574 if (ifpp) 575 *ifpp = ifp; 576 } 577 578 return 0; 579 } 580 #ifdef HAVE_NRL_INPCB 581 #undef in6p_outputopts 582 #undef in6p_moptions 583 #endif 584 585 /* 586 * generate standard sockaddr_in6 from embedded form. 587 * touches sin6_addr and sin6_scope_id only. 588 * 589 * this function should be nuked in the future, when we get rid of 590 * embedded scopeid thing. 591 */ 592 int 593 in6_recoverscope(struct sockaddr_in6 *sin6, const struct in6_addr *in6, 594 struct ifnet *ifp) 595 { 596 u_int32_t zoneid; 597 598 sin6->sin6_addr = *in6; 599 600 /* 601 * don't try to read *in6 beyond here, since the caller may 602 * ask us to overwrite existing sockaddr_in6 603 */ 604 605 sin6->sin6_scope_id = 0; 606 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 607 /* 608 * KAME assumption: link id == interface id 609 */ 610 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 611 if (zoneid) { 612 /* sanity check */ 613 if (zoneid < 0 || if_index < zoneid) 614 return ENXIO; 615 if (ifp && ifp->if_index != zoneid) 616 return ENXIO; 617 sin6->sin6_addr.s6_addr16[1] = 0; 618 sin6->sin6_scope_id = zoneid; 619 } 620 } 621 622 return 0; 623 } 624 625 /* 626 * just clear the embedded scope identifier. 627 */ 628 void 629 in6_clearscope(struct in6_addr *addr) 630 { 631 if (IN6_IS_SCOPE_LINKLOCAL(addr) || IN6_IS_ADDR_MC_INTFACELOCAL(addr)) 632 addr->s6_addr16[1] = 0; 633 } 634 635 void 636 addrsel_policy_init(void) 637 { 638 639 init_policy_queue(); 640 641 /* initialize the "last resort" policy */ 642 bzero(&defaultaddrpolicy, sizeof(defaultaddrpolicy)); 643 defaultaddrpolicy.label = ADDR_LABEL_NOTAPP; 644 } 645 646 /* 647 * Subroutines to manage the address selection policy table via sysctl. 648 */ 649 struct walkarg { 650 struct sysctl_req *w_req; 651 }; 652 653 static int in6_src_sysctl(SYSCTL_HANDLER_ARGS); 654 SYSCTL_DECL(_net_inet6_ip6); 655 SYSCTL_NODE(_net_inet6_ip6, IPV6CTL_ADDRCTLPOLICY, addrctlpolicy, 656 CTLFLAG_RD, in6_src_sysctl, "Address selection policy"); 657 658 static int 659 in6_src_sysctl(SYSCTL_HANDLER_ARGS) 660 { 661 struct walkarg w; 662 663 if (req->newptr) 664 return EPERM; 665 666 bzero(&w, sizeof(w)); 667 w.w_req = req; 668 669 return (walk_addrsel_policy(dump_addrsel_policyent, &w)); 670 } 671 672 int 673 in6_src_ioctl(u_long cmd, caddr_t data) 674 { 675 int i; 676 struct in6_addrpolicy ent0; 677 678 if (cmd != SIOCAADDRCTL_POLICY && cmd != SIOCDADDRCTL_POLICY) 679 return (EOPNOTSUPP); /* check for safety */ 680 681 ent0 = *(struct in6_addrpolicy *)data; 682 683 if (ent0.label == ADDR_LABEL_NOTAPP) 684 return (EINVAL); 685 /* check if the prefix mask is consecutive. */ 686 if (in6_mask2len(&ent0.addrmask.sin6_addr, NULL) < 0) 687 return (EINVAL); 688 /* clear trailing garbages (if any) of the prefix address. */ 689 for (i = 0; i < 4; i++) { 690 ent0.addr.sin6_addr.s6_addr32[i] &= 691 ent0.addrmask.sin6_addr.s6_addr32[i]; 692 } 693 ent0.use = 0; 694 695 switch (cmd) { 696 case SIOCAADDRCTL_POLICY: 697 return (add_addrsel_policyent(&ent0)); 698 case SIOCDADDRCTL_POLICY: 699 return (delete_addrsel_policyent(&ent0)); 700 } 701 702 return (0); /* XXX: compromise compilers */ 703 } 704 705 /* 706 * The followings are implementation of the policy table using a 707 * simple tail queue. 708 * XXX such details should be hidden. 709 * XXX implementation using binary tree should be more efficient. 710 */ 711 struct addrsel_policyent { 712 TAILQ_ENTRY(addrsel_policyent) ape_entry; 713 struct in6_addrpolicy ape_policy; 714 }; 715 716 TAILQ_HEAD(addrsel_policyhead, addrsel_policyent); 717 718 struct addrsel_policyhead addrsel_policytab; 719 720 static void 721 init_policy_queue(void) 722 { 723 TAILQ_INIT(&addrsel_policytab); 724 } 725 726 static int 727 add_addrsel_policyent(struct in6_addrpolicy *newpolicy) 728 { 729 struct addrsel_policyent *new, *pol; 730 731 /* duplication check */ 732 for (pol = TAILQ_FIRST(&addrsel_policytab); pol; 733 pol = TAILQ_NEXT(pol, ape_entry)) { 734 if (SA6_ARE_ADDR_EQUAL(&newpolicy->addr, 735 &pol->ape_policy.addr) && 736 SA6_ARE_ADDR_EQUAL(&newpolicy->addrmask, 737 &pol->ape_policy.addrmask)) { 738 return (EEXIST); /* or override it? */ 739 } 740 } 741 742 new = kmalloc(sizeof(*new), M_IFADDR, M_WAITOK | M_ZERO); 743 744 /* XXX: should validate entry */ 745 new->ape_policy = *newpolicy; 746 747 TAILQ_INSERT_TAIL(&addrsel_policytab, new, ape_entry); 748 749 return (0); 750 } 751 752 static int 753 delete_addrsel_policyent(struct in6_addrpolicy *key) 754 { 755 struct addrsel_policyent *pol; 756 757 /* search for the entry in the table */ 758 for (pol = TAILQ_FIRST(&addrsel_policytab); pol; 759 pol = TAILQ_NEXT(pol, ape_entry)) { 760 if (SA6_ARE_ADDR_EQUAL(&key->addr, &pol->ape_policy.addr) && 761 SA6_ARE_ADDR_EQUAL(&key->addrmask, 762 &pol->ape_policy.addrmask)) { 763 break; 764 } 765 } 766 if (pol == NULL) 767 return (ESRCH); 768 769 TAILQ_REMOVE(&addrsel_policytab, pol, ape_entry); 770 kfree(pol, M_IFADDR); 771 772 return (0); 773 } 774 775 static int 776 walk_addrsel_policy(int(*callback)(struct in6_addrpolicy *, void *), void *w) 777 { 778 struct addrsel_policyent *pol; 779 int error = 0; 780 781 for (pol = TAILQ_FIRST(&addrsel_policytab); pol; 782 pol = TAILQ_NEXT(pol, ape_entry)) { 783 if ((error = (*callback)(&pol->ape_policy, w)) != 0) 784 return (error); 785 } 786 787 return (error); 788 } 789 790 static int 791 dump_addrsel_policyent(struct in6_addrpolicy *pol, void *arg) 792 { 793 int error = 0; 794 struct walkarg *w = arg; 795 796 error = SYSCTL_OUT(w->w_req, pol, sizeof(*pol)); 797 798 return (error); 799 } 800