2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the project nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * $KAME: in6_src.c,v 1.132 2003/08/26 04:42:27 keiichi Exp $
35 * Copyright (c) 1982, 1986, 1991, 1993
36 * The Regents of the University of California. All rights reserved.
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
41 * 1. Redistributions of source code must retain the above copyright
42 * notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 * notice, this list of conditions and the following disclaimer in the
45 * documentation and/or other materials provided with the distribution.
46 * 3. Neither the name of the University nor the names of its contributors
47 * may be used to endorse or promote products derived from this software
48 * without specific prior written permission.
50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62 * @(#)in_pcb.c 8.2 (Berkeley) 1/4/94
65 #include <sys/cdefs.h>
66 __FBSDID("$FreeBSD$");
69 #include "opt_inet6.h"
70 #include <sys/param.h>
71 #include <sys/systm.h>
73 #include <sys/malloc.h>
76 #include <sys/protosw.h>
77 #include <sys/socket.h>
78 #include <sys/socketvar.h>
79 #include <sys/sockio.h>
80 #include <sys/sysctl.h>
81 #include <sys/errno.h>
84 #include <sys/kernel.h>
85 #include <sys/rmlock.h>
89 #include <net/if_var.h>
90 #include <net/if_dl.h>
91 #include <net/route.h>
92 #include <net/route/nhop.h>
93 #include <net/if_llatbl.h>
95 #include <netinet/in.h>
96 #include <netinet/in_var.h>
97 #include <netinet/in_systm.h>
98 #include <netinet/ip.h>
99 #include <netinet/in_pcb.h>
100 #include <netinet/ip_var.h>
101 #include <netinet/udp.h>
102 #include <netinet/udp_var.h>
104 #include <netinet6/in6_var.h>
105 #include <netinet/ip6.h>
106 #include <netinet6/in6_fib.h>
107 #include <netinet6/in6_pcb.h>
108 #include <netinet6/ip6_var.h>
109 #include <netinet6/scope6_var.h>
110 #include <netinet6/nd6.h>
112 static struct mtx addrsel_lock;
113 #define ADDRSEL_LOCK_INIT() mtx_init(&addrsel_lock, "addrsel_lock", NULL, MTX_DEF)
114 #define ADDRSEL_LOCK() mtx_lock(&addrsel_lock)
115 #define ADDRSEL_UNLOCK() mtx_unlock(&addrsel_lock)
116 #define ADDRSEL_LOCK_ASSERT() mtx_assert(&addrsel_lock, MA_OWNED)
118 static struct sx addrsel_sxlock;
119 #define ADDRSEL_SXLOCK_INIT() sx_init(&addrsel_sxlock, "addrsel_sxlock")
120 #define ADDRSEL_SLOCK() sx_slock(&addrsel_sxlock)
121 #define ADDRSEL_SUNLOCK() sx_sunlock(&addrsel_sxlock)
122 #define ADDRSEL_XLOCK() sx_xlock(&addrsel_sxlock)
123 #define ADDRSEL_XUNLOCK() sx_xunlock(&addrsel_sxlock)
125 #define ADDR_LABEL_NOTAPP (-1)
126 VNET_DEFINE_STATIC(struct in6_addrpolicy, defaultaddrpolicy);
127 #define V_defaultaddrpolicy VNET(defaultaddrpolicy)
129 VNET_DEFINE(int, ip6_prefer_tempaddr) = 0;
131 static int selectroute(struct sockaddr_in6 *, struct ip6_pktopts *,
132 struct ip6_moptions *, struct route_in6 *, struct ifnet **,
133 struct nhop_object **, int, u_int, uint32_t);
134 static int in6_selectif(struct sockaddr_in6 *, struct ip6_pktopts *,
135 struct ip6_moptions *, struct ifnet **,
136 struct ifnet *, u_int);
137 static int in6_selectsrc(uint32_t, struct sockaddr_in6 *,
138 struct ip6_pktopts *, struct inpcb *, struct ucred *,
139 struct ifnet **, struct in6_addr *);
141 static struct in6_addrpolicy *lookup_addrsel_policy(struct sockaddr_in6 *);
143 static void init_policy_queue(void);
144 static int add_addrsel_policyent(struct in6_addrpolicy *);
145 static int delete_addrsel_policyent(struct in6_addrpolicy *);
146 static int walk_addrsel_policy(int (*)(struct in6_addrpolicy *, void *),
148 static int dump_addrsel_policyent(struct in6_addrpolicy *, void *);
149 static struct in6_addrpolicy *match_addrsel_policy(struct sockaddr_in6 *);
152 * Return an IPv6 address, which is the most appropriate for a given
153 * destination and user specified options.
154 * If necessary, this function lookups the routing table and returns
155 * an entry to the caller for later use.
157 #define REPLACE(r) do {\
158 IP6STAT_INC(ip6s_sources_rule[(r)]); \
160 char ip6buf[INET6_ADDRSTRLEN], ip6b[INET6_ADDRSTRLEN]; \
161 printf("in6_selectsrc: replace %s with %s by %d\n", ia_best ? ip6_sprintf(ip6buf, &ia_best->ia_addr.sin6_addr) : "none", ip6_sprintf(ip6b, &ia->ia_addr.sin6_addr), (r)); \
165 #define NEXT(r) do {\
167 char ip6buf[INET6_ADDRSTRLEN], ip6b[INET6_ADDRSTRLEN]; \
168 printf("in6_selectsrc: keep %s against %s by %d\n", ia_best ? ip6_sprintf(ip6buf, &ia_best->ia_addr.sin6_addr) : "none", ip6_sprintf(ip6b, &ia->ia_addr.sin6_addr), (r)); \
170 goto next; /* XXX: we can't use 'continue' here */ \
172 #define BREAK(r) do { \
173 IP6STAT_INC(ip6s_sources_rule[(r)]); \
174 goto out; /* XXX: we can't use 'break' here */ \
178 in6_selectsrc(uint32_t fibnum, struct sockaddr_in6 *dstsock,
179 struct ip6_pktopts *opts, struct inpcb *inp, struct ucred *cred,
180 struct ifnet **ifpp, struct in6_addr *srcp)
182 struct rm_priotracker in6_ifa_tracker;
183 struct in6_addr dst, tmp;
184 struct ifnet *ifp = NULL, *oifp = NULL;
185 struct in6_ifaddr *ia = NULL, *ia_best = NULL;
186 struct in6_pktinfo *pi = NULL;
187 int dst_scope = -1, best_scope = -1, best_matchlen = -1;
188 struct in6_addrpolicy *dst_policy = NULL, *best_policy = NULL;
192 struct ip6_moptions *mopts;
194 KASSERT(srcp != NULL, ("%s: srcp is NULL", __func__));
196 dst = dstsock->sin6_addr; /* make a copy for local operation */
199 * Save a possibly passed in ifp for in6_selectsrc. Only
200 * neighbor discovery code should use this feature, where
201 * we may know the interface but not the FIB number holding
202 * the connected subnet in case someone deleted it from the
203 * default FIB and we need to check the interface.
211 INP_LOCK_ASSERT(inp);
212 mopts = inp->in6p_moptions;
218 * If the source address is explicitly specified by the caller,
219 * check if the requested source address is indeed a unicast address
220 * assigned to the node, and can be used as the packet's source
221 * address. If everything is okay, use the address as source.
223 if (opts && (pi = opts->ip6po_pktinfo) &&
224 !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) {
225 /* get the outgoing interface */
226 if ((error = in6_selectif(dstsock, opts, mopts, &ifp, oifp,
232 * determine the appropriate zone id of the source based on
233 * the zone of the destination and the outgoing interface.
234 * If the specified address is ambiguous wrt the scope zone,
235 * the interface must be specified; otherwise, ifa_ifwithaddr()
236 * will fail matching the address.
240 error = in6_setscope(&tmp, ifp, &odstzone);
244 if (cred != NULL && (error = prison_local_ip6(cred,
245 &tmp, (inp->inp_flags & IN6P_IPV6_V6ONLY) != 0)) != 0)
249 * If IPV6_BINDANY socket option is set, we allow to specify
250 * non local addresses as source address in IPV6_PKTINFO
253 if ((inp->inp_flags & INP_BINDANY) == 0) {
254 ia = in6ifa_ifwithaddr(&tmp, 0 /* XXX */);
255 if (ia == NULL || (ia->ia6_flags & (IN6_IFF_ANYCAST |
256 IN6_IFF_NOTREADY))) {
258 ifa_free(&ia->ia_ifa);
259 return (EADDRNOTAVAIL);
261 bcopy(&ia->ia_addr.sin6_addr, srcp, sizeof(*srcp));
262 ifa_free(&ia->ia_ifa);
264 bcopy(&tmp, srcp, sizeof(*srcp));
265 pi->ipi6_addr = tmp; /* XXX: this overrides pi */
272 * Otherwise, if the socket has already bound the source, just use it.
274 if (inp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
276 (error = prison_local_ip6(cred, &inp->in6p_laddr,
277 ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0))) != 0)
279 bcopy(&inp->in6p_laddr, srcp, sizeof(*srcp));
284 * Bypass source address selection and use the primary jail IP
287 if (cred != NULL && !prison_saddrsel_ip6(cred, srcp))
291 * If the address is not specified, choose the best one based on
292 * the outgoing interface and the destination address.
294 /* get the outgoing interface */
295 if ((error = in6_selectif(dstsock, opts, mopts, &ifp, oifp,
296 (inp != NULL) ? inp->inp_inc.inc_fibnum : fibnum)) != 0)
300 if (ifp == NULL) /* this should not happen */
301 panic("in6_selectsrc: NULL ifp");
303 error = in6_setscope(&dst, ifp, &odstzone);
307 IN6_IFADDR_RLOCK(&in6_ifa_tracker);
308 CK_STAILQ_FOREACH(ia, &V_in6_ifaddrhead, ia_link) {
309 int new_scope = -1, new_matchlen = -1;
310 struct in6_addrpolicy *new_policy = NULL;
311 u_int32_t srczone, osrczone, dstzone;
313 struct ifnet *ifp1 = ia->ia_ifp;
316 * We'll never take an address that breaks the scope zone
317 * of the destination. We also skip an address if its zone
318 * does not contain the outgoing interface.
319 * XXX: we should probably use sin6_scope_id here.
321 if (in6_setscope(&dst, ifp1, &dstzone) ||
322 odstzone != dstzone) {
325 src = ia->ia_addr.sin6_addr;
326 if (in6_setscope(&src, ifp, &osrczone) ||
327 in6_setscope(&src, ifp1, &srczone) ||
328 osrczone != srczone) {
332 /* avoid unusable addresses */
334 (IN6_IFF_NOTREADY | IN6_IFF_ANYCAST | IN6_IFF_DETACHED))) {
337 if (!V_ip6_use_deprecated && IFA6_IS_DEPRECATED(ia))
340 /* If jailed only take addresses of the jail into account. */
342 prison_check_ip6(cred, &ia->ia_addr.sin6_addr) != 0)
345 /* Rule 1: Prefer same address */
346 if (IN6_ARE_ADDR_EQUAL(&dst, &ia->ia_addr.sin6_addr)) {
348 BREAK(1); /* there should be no better candidate */
354 /* Rule 2: Prefer appropriate scope */
356 dst_scope = in6_addrscope(&dst);
357 new_scope = in6_addrscope(&ia->ia_addr.sin6_addr);
358 if (IN6_ARE_SCOPE_CMP(best_scope, new_scope) < 0) {
359 if (IN6_ARE_SCOPE_CMP(best_scope, dst_scope) < 0)
362 } else if (IN6_ARE_SCOPE_CMP(new_scope, best_scope) < 0) {
363 if (IN6_ARE_SCOPE_CMP(new_scope, dst_scope) < 0)
369 * Rule 3: Avoid deprecated addresses. Note that the case of
370 * !ip6_use_deprecated is already rejected above.
372 if (!IFA6_IS_DEPRECATED(ia_best) && IFA6_IS_DEPRECATED(ia))
374 if (IFA6_IS_DEPRECATED(ia_best) && !IFA6_IS_DEPRECATED(ia))
377 /* Rule 4: Prefer home addresses */
379 * XXX: This is a TODO. We should probably merge the MIP6
383 /* Rule 5: Prefer outgoing interface */
384 if (!(ND_IFINFO(ifp)->flags & ND6_IFF_NO_PREFER_IFACE)) {
385 if (ia_best->ia_ifp == ifp && ia->ia_ifp != ifp)
387 if (ia_best->ia_ifp != ifp && ia->ia_ifp == ifp)
392 * Rule 6: Prefer matching label
393 * Note that best_policy should be non-NULL here.
395 if (dst_policy == NULL)
396 dst_policy = lookup_addrsel_policy(dstsock);
397 if (dst_policy->label != ADDR_LABEL_NOTAPP) {
398 new_policy = lookup_addrsel_policy(&ia->ia_addr);
399 if (dst_policy->label == best_policy->label &&
400 dst_policy->label != new_policy->label)
402 if (dst_policy->label != best_policy->label &&
403 dst_policy->label == new_policy->label)
408 * Rule 7: Prefer public addresses.
409 * We allow users to reverse the logic by configuring
410 * a sysctl variable, so that privacy conscious users can
411 * always prefer temporary addresses.
414 opts->ip6po_prefer_tempaddr == IP6PO_TEMPADDR_SYSTEM) {
415 prefer_tempaddr = V_ip6_prefer_tempaddr;
416 } else if (opts->ip6po_prefer_tempaddr ==
417 IP6PO_TEMPADDR_NOTPREFER) {
421 if (!(ia_best->ia6_flags & IN6_IFF_TEMPORARY) &&
422 (ia->ia6_flags & IN6_IFF_TEMPORARY)) {
428 if ((ia_best->ia6_flags & IN6_IFF_TEMPORARY) &&
429 !(ia->ia6_flags & IN6_IFF_TEMPORARY)) {
437 * Rule 8: prefer addresses on alive interfaces.
438 * This is a KAME specific rule.
440 if ((ia_best->ia_ifp->if_flags & IFF_UP) &&
441 !(ia->ia_ifp->if_flags & IFF_UP))
443 if (!(ia_best->ia_ifp->if_flags & IFF_UP) &&
444 (ia->ia_ifp->if_flags & IFF_UP))
448 * Rule 9: prefer address with better virtual status.
450 if (ifa_preferred(&ia_best->ia_ifa, &ia->ia_ifa))
452 if (ifa_preferred(&ia->ia_ifa, &ia_best->ia_ifa))
456 * Rule 10: prefer address with `prefer_source' flag.
458 if ((ia_best->ia6_flags & IN6_IFF_PREFER_SOURCE) == 0 &&
459 (ia->ia6_flags & IN6_IFF_PREFER_SOURCE) != 0)
461 if ((ia_best->ia6_flags & IN6_IFF_PREFER_SOURCE) != 0 &&
462 (ia->ia6_flags & IN6_IFF_PREFER_SOURCE) == 0)
466 * Rule 14: Use longest matching prefix.
467 * Note: in the address selection draft, this rule is
468 * documented as "Rule 8". However, since it is also
469 * documented that this rule can be overridden, we assign
470 * a large number so that it is easy to assign smaller numbers
471 * to more preferred rules.
473 new_matchlen = in6_matchlen(&ia->ia_addr.sin6_addr, &dst);
474 if (best_matchlen < new_matchlen)
476 if (new_matchlen < best_matchlen)
479 /* Rule 15 is reserved. */
482 * Last resort: just keep the current candidate.
483 * Or, do we need more rules?
489 best_scope = (new_scope >= 0 ? new_scope :
490 in6_addrscope(&ia_best->ia_addr.sin6_addr));
491 best_policy = (new_policy ? new_policy :
492 lookup_addrsel_policy(&ia_best->ia_addr));
493 best_matchlen = (new_matchlen >= 0 ? new_matchlen :
494 in6_matchlen(&ia_best->ia_addr.sin6_addr,
504 if ((ia = ia_best) == NULL) {
505 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
506 IP6STAT_INC(ip6s_sources_none);
507 return (EADDRNOTAVAIL);
511 * At this point at least one of the addresses belonged to the jail
512 * but it could still be, that we want to further restrict it, e.g.
513 * theoratically IN6_IS_ADDR_LOOPBACK.
514 * It must not be IN6_IS_ADDR_UNSPECIFIED anymore.
515 * prison_local_ip6() will fix an IN6_IS_ADDR_LOOPBACK but should
516 * let all others previously selected pass.
517 * Use tmp to not change ::1 on lo0 to the primary jail address.
519 tmp = ia->ia_addr.sin6_addr;
520 if (cred != NULL && prison_local_ip6(cred, &tmp, (inp != NULL &&
521 (inp->inp_flags & IN6P_IPV6_V6ONLY) != 0)) != 0) {
522 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
523 IP6STAT_INC(ip6s_sources_none);
524 return (EADDRNOTAVAIL);
530 bcopy(&tmp, srcp, sizeof(*srcp));
531 if (ia->ia_ifp == ifp)
532 IP6STAT_INC(ip6s_sources_sameif[best_scope]);
534 IP6STAT_INC(ip6s_sources_otherif[best_scope]);
535 if (dst_scope == best_scope)
536 IP6STAT_INC(ip6s_sources_samescope[best_scope]);
538 IP6STAT_INC(ip6s_sources_otherscope[best_scope]);
539 if (IFA6_IS_DEPRECATED(ia))
540 IP6STAT_INC(ip6s_sources_deprecated[best_scope]);
541 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
546 * Select source address based on @inp, @dstsock and @opts.
547 * Stores selected address to @srcp. If @scope_ambiguous is set,
548 * embed scope from selected outgoing interface. If @hlim pointer
549 * is provided, stores calculated hop limit there.
550 * Returns 0 on success.
553 in6_selectsrc_socket(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
554 struct inpcb *inp, struct ucred *cred, int scope_ambiguous,
555 struct in6_addr *srcp, int *hlim)
557 struct ifnet *retifp;
561 fibnum = inp->inp_inc.inc_fibnum;
564 error = in6_selectsrc(fibnum, dstsock, opts, inp, cred, &retifp, srcp);
569 *hlim = in6_selecthlim(inp, retifp);
571 if (retifp == NULL || scope_ambiguous == 0)
575 * Application should provide a proper zone ID or the use of
576 * default zone IDs should be enabled. Unfortunately, some
577 * applications do not behave as it should, so we need a
578 * workaround. Even if an appropriate ID is not determined
579 * (when it's required), if we can determine the outgoing
580 * interface. determine the zone ID based on the interface.
582 error = in6_setscope(&dstsock->sin6_addr, retifp, NULL);
588 * Select source address based on @fibnum, @dst and @scopeid.
589 * Stores selected address to @srcp.
590 * Returns 0 on success.
592 * Used by non-socket based consumers (ND code mostly)
595 in6_selectsrc_addr(uint32_t fibnum, const struct in6_addr *dst,
596 uint32_t scopeid, struct ifnet *ifp, struct in6_addr *srcp,
599 struct ifnet *retifp;
600 struct sockaddr_in6 dst_sa;
604 bzero(&dst_sa, sizeof(dst_sa));
605 dst_sa.sin6_family = AF_INET6;
606 dst_sa.sin6_len = sizeof(dst_sa);
607 dst_sa.sin6_addr = *dst;
608 dst_sa.sin6_scope_id = scopeid;
609 sa6_embedscope(&dst_sa, 0);
611 error = in6_selectsrc(fibnum, &dst_sa, NULL, NULL, NULL, &retifp, srcp);
613 *hlim = in6_selecthlim(NULL, retifp);
619 * clone - meaningful only for bsdi and freebsd
622 selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
623 struct ip6_moptions *mopts, struct route_in6 *ro,
624 struct ifnet **retifp, struct nhop_object **retnh, int norouteok,
625 u_int fibnum, uint32_t flowid)
628 struct ifnet *ifp = NULL;
629 struct nhop_object *nh = NULL;
630 struct sockaddr_in6 *sin6_next;
631 struct in6_pktinfo *pi = NULL;
632 struct in6_addr *dst = &dstsock->sin6_addr;
635 char ip6buf[INET6_ADDRSTRLEN];
637 if (dstsock->sin6_addr.s6_addr32[0] == 0 &&
638 dstsock->sin6_addr.s6_addr32[1] == 0 &&
639 !IN6_IS_ADDR_LOOPBACK(&dstsock->sin6_addr)) {
640 printf("%s: strange destination %s\n", __func__,
641 ip6_sprintf(ip6buf, &dstsock->sin6_addr));
643 printf("%s: destination = %s%%%d\n", __func__,
644 ip6_sprintf(ip6buf, &dstsock->sin6_addr),
645 dstsock->sin6_scope_id); /* for debug */
649 /* If the caller specify the outgoing interface explicitly, use it. */
650 if (opts && (pi = opts->ip6po_pktinfo) != NULL && pi->ipi6_ifindex) {
651 /* XXX boundary check is assumed to be already done. */
652 ifp = ifnet_byindex(pi->ipi6_ifindex);
654 (norouteok || retnh == NULL ||
655 IN6_IS_ADDR_MULTICAST(dst))) {
657 * we do not have to check or get the route for
665 * If the destination address is a multicast address and the outgoing
666 * interface for the address is specified by the caller, use it.
668 if (IN6_IS_ADDR_MULTICAST(dst) &&
669 mopts != NULL && (ifp = mopts->im6o_multicast_ifp) != NULL) {
670 goto done; /* we do not need a route for multicast. */
673 * If destination address is LLA or link- or node-local multicast,
674 * use it's embedded scope zone id to determine outgoing interface.
676 if (IN6_IS_ADDR_MC_LINKLOCAL(dst) ||
677 IN6_IS_ADDR_MC_NODELOCAL(dst)) {
678 zoneid = ntohs(in6_getscope(dst));
680 ifp = in6_getlinkifnet(zoneid);
687 * If the next hop address for the packet is specified by the caller,
688 * use it as the gateway.
690 if (opts && opts->ip6po_nexthop) {
691 struct route_in6 *ron;
693 sin6_next = satosin6(opts->ip6po_nexthop);
694 if (IN6_IS_ADDR_LINKLOCAL(&sin6_next->sin6_addr)) {
696 * Next hop is LLA, thus it should be neighbor.
697 * Determine outgoing interface by zone index.
699 zoneid = ntohs(in6_getscope(&sin6_next->sin6_addr));
701 ifp = in6_getlinkifnet(zoneid);
705 ron = &opts->ip6po_nextroute;
706 /* Use a cached route if it exists and is valid. */
707 if (ron->ro_nh != NULL && (
708 !NH_IS_VALID(ron->ro_nh) ||
709 ron->ro_dst.sin6_family != AF_INET6 ||
710 !IN6_ARE_ADDR_EQUAL(&ron->ro_dst.sin6_addr,
711 &sin6_next->sin6_addr)))
713 if (ron->ro_nh == NULL) {
714 ron->ro_dst = *sin6_next;
716 * sin6_next is not link-local OR scopeid is 0,
717 * no need to clear scope
719 ron->ro_nh = fib6_lookup(fibnum,
720 &sin6_next->sin6_addr, 0, NHR_REF, flowid);
723 * The node identified by that address must be a
724 * neighbor of the sending host.
726 if (ron->ro_nh == NULL ||
727 (ron->ro_nh->nh_flags & NHF_GATEWAY) != 0)
728 error = EHOSTUNREACH;
737 * Use a cached route if it exists and is valid, else try to allocate
738 * a new one. Note that we should check the address family of the
739 * cached destination, in case of sharing the cache with IPv4.
743 (!NH_IS_VALID(ro->ro_nh) ||
744 ((struct sockaddr *)(&ro->ro_dst))->sa_family != AF_INET6 ||
745 !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr,
749 if (ro->ro_nh == (struct nhop_object *)NULL) {
750 struct sockaddr_in6 *sa6;
752 /* No route yet, so try to acquire one */
753 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6));
754 sa6 = (struct sockaddr_in6 *)&ro->ro_dst;
756 sa6->sin6_scope_id = 0;
759 * Currently dst has scopeid embedded iff it is LL.
760 * New routing API accepts scopeid as a separate argument.
761 * Convert dst before/after doing lookup
763 uint32_t scopeid = 0;
764 if (IN6_IS_SCOPE_LINKLOCAL(&sa6->sin6_addr)) {
765 /* Unwrap in6_getscope() and in6_clearscope() */
766 scopeid = ntohs(sa6->sin6_addr.s6_addr16[1]);
767 sa6->sin6_addr.s6_addr16[1] = 0;
770 ro->ro_nh = fib6_lookup(fibnum,
771 &sa6->sin6_addr, scopeid, NHR_REF, flowid);
773 if (IN6_IS_SCOPE_LINKLOCAL(&sa6->sin6_addr))
774 sa6->sin6_addr.s6_addr16[1] = htons(scopeid);
778 * do not care about the result if we have the nexthop
779 * explicitly specified.
781 if (opts && opts->ip6po_nexthop)
785 ifp = ro->ro_nh->nh_ifp;
787 error = EHOSTUNREACH;
791 * Check if the outgoing interface conflicts with
792 * the interface specified by ipi6_ifindex (if specified).
793 * Note that loopback interface is always okay.
794 * (this may happen when we are sending a packet to one of
795 * our own addresses.)
797 if (ifp && opts && opts->ip6po_pktinfo &&
798 opts->ip6po_pktinfo->ipi6_ifindex) {
799 if (!(ifp->if_flags & IFF_LOOPBACK) &&
801 opts->ip6po_pktinfo->ipi6_ifindex) {
802 error = EHOSTUNREACH;
809 if (ifp == NULL && nh == NULL) {
811 * This can happen if the caller did not pass a cached route
812 * nor any other hints. We treat this case an error.
814 error = EHOSTUNREACH;
816 if (error == EHOSTUNREACH)
817 IP6STAT_INC(ip6s_noroute);
819 if (retifp != NULL) {
821 *retifp = nh->nh_aifp;
827 *retnh = nh; /* nh may be NULL */
833 in6_selectif(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
834 struct ip6_moptions *mopts, struct ifnet **retifp,
835 struct ifnet *oifp, u_int fibnum)
838 struct route_in6 sro;
839 struct nhop_object *nh = NULL;
842 KASSERT(retifp != NULL, ("%s: retifp is NULL", __func__));
844 bzero(&sro, sizeof(sro));
847 error = selectroute(dstsock, opts, mopts, &sro, retifp, &nh, 1, fibnum, 0);
850 nh_flags = nh->nh_flags;
851 if (nh != NULL && nh == sro.ro_nh)
855 /* Help ND. See oifp comment in in6_selectsrc(). */
856 if (oifp != NULL && fibnum == RT_DEFAULT_FIB) {
864 * do not use a rejected or black hole route.
865 * XXX: this check should be done in the L2 output routine.
866 * However, if we skipped this check here, we'd see the following
868 * - install a rejected route for a scoped address prefix
870 * - send a packet to a destination that matches the scoped prefix,
871 * with ambiguity about the scope zone.
872 * - pick the outgoing interface from the route, and disambiguate the
873 * scope zone with the interface.
874 * - ip6_output() would try to get another route with the "new"
875 * destination, which may be valid.
876 * - we'd see no error on output.
877 * Although this may not be very harmful, it should still be confusing.
878 * We thus reject the case here.
881 if (nh_flags & (NHF_REJECT | NHF_BLACKHOLE)) {
882 error = (nh_flags & NHF_HOST ? EHOSTUNREACH : ENETUNREACH);
889 /* Public wrapper function to selectroute(). */
891 in6_selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
892 struct ip6_moptions *mopts, struct route_in6 *ro,
893 struct ifnet **retifp, struct nhop_object **retnh, u_int fibnum, uint32_t flowid)
896 return (selectroute(dstsock, opts, mopts, ro, retifp,
897 retnh, 0, fibnum, flowid));
901 * Default hop limit selection. The precedence is as follows:
902 * 1. Hoplimit value specified via ioctl.
903 * 2. (If the outgoing interface is detected) the current
904 * hop limit of the interface specified by router advertisement.
905 * 3. The system default hoplimit.
908 in6_selecthlim(struct inpcb *inp, struct ifnet *ifp)
911 if (inp && inp->in6p_hops >= 0)
912 return (inp->in6p_hops);
914 return (ND_IFINFO(ifp)->chlim);
915 else if (inp && !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
916 struct nhop_object *nh;
918 uint32_t fibnum, scopeid;
921 fibnum = inp->inp_inc.inc_fibnum;
922 in6_splitscope(&inp->in6p_faddr, &dst, &scopeid);
923 nh = fib6_lookup(fibnum, &dst, scopeid, 0, 0);
925 hlim = ND_IFINFO(nh->nh_ifp)->chlim;
929 return (V_ip6_defhlim);
933 * XXX: this is borrowed from in6_pcbbind(). If possible, we should
934 * share this function by all *bsd*...
937 in6_pcbsetport(struct in6_addr *laddr, struct inpcb *inp, struct ucred *cred)
939 struct socket *so = inp->inp_socket;
941 int error, lookupflags = 0;
943 struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
946 INP_WLOCK_ASSERT(inp);
947 INP_HASH_WLOCK_ASSERT(pcbinfo);
949 error = prison_local_ip6(cred, laddr,
950 ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0));
954 /* XXX: this is redundant when called from in6_pcbbind */
955 if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT|SO_REUSEPORT_LB)) == 0)
956 lookupflags = INPLOOKUP_WILDCARD;
958 inp->inp_flags |= INP_ANONPORT;
960 error = in_pcb_lport(inp, NULL, &lport, cred, lookupflags);
964 inp->inp_lport = lport;
965 if (in_pcbinshash(inp) != 0) {
966 inp->in6p_laddr = in6addr_any;
975 addrsel_policy_init(void)
980 /* initialize the "last resort" policy */
981 bzero(&V_defaultaddrpolicy, sizeof(V_defaultaddrpolicy));
982 V_defaultaddrpolicy.label = ADDR_LABEL_NOTAPP;
984 if (!IS_DEFAULT_VNET(curvnet))
988 ADDRSEL_SXLOCK_INIT();
991 static struct in6_addrpolicy *
992 lookup_addrsel_policy(struct sockaddr_in6 *key)
994 struct in6_addrpolicy *match = NULL;
997 match = match_addrsel_policy(key);
1000 match = &V_defaultaddrpolicy;
1009 * Subroutines to manage the address selection policy table via sysctl.
1012 struct sysctl_req *w_req;
1015 static int in6_src_sysctl(SYSCTL_HANDLER_ARGS);
1016 SYSCTL_DECL(_net_inet6_ip6);
1017 static SYSCTL_NODE(_net_inet6_ip6, IPV6CTL_ADDRCTLPOLICY, addrctlpolicy,
1018 CTLFLAG_RD | CTLFLAG_MPSAFE, in6_src_sysctl,
1022 in6_src_sysctl(SYSCTL_HANDLER_ARGS)
1029 bzero(&w, sizeof(w));
1032 return (walk_addrsel_policy(dump_addrsel_policyent, &w));
1036 in6_src_ioctl(u_long cmd, caddr_t data)
1038 struct in6_addrpolicy ent0;
1040 if (cmd != SIOCAADDRCTL_POLICY && cmd != SIOCDADDRCTL_POLICY)
1041 return (EOPNOTSUPP); /* check for safety */
1043 ent0 = *(struct in6_addrpolicy *)data;
1045 if (ent0.label == ADDR_LABEL_NOTAPP)
1047 /* check if the prefix mask is consecutive. */
1048 if (in6_mask2len(&ent0.addrmask.sin6_addr, NULL) < 0)
1050 /* clear trailing garbages (if any) of the prefix address. */
1051 IN6_MASK_ADDR(&ent0.addr.sin6_addr, &ent0.addrmask.sin6_addr);
1055 case SIOCAADDRCTL_POLICY:
1056 return (add_addrsel_policyent(&ent0));
1057 case SIOCDADDRCTL_POLICY:
1058 return (delete_addrsel_policyent(&ent0));
1061 return (0); /* XXX: compromise compilers */
1065 * The followings are implementation of the policy table using a
1066 * simple tail queue.
1067 * XXX such details should be hidden.
1068 * XXX implementation using binary tree should be more efficient.
1070 struct addrsel_policyent {
1071 TAILQ_ENTRY(addrsel_policyent) ape_entry;
1072 struct in6_addrpolicy ape_policy;
1075 TAILQ_HEAD(addrsel_policyhead, addrsel_policyent);
1077 VNET_DEFINE_STATIC(struct addrsel_policyhead, addrsel_policytab);
1078 #define V_addrsel_policytab VNET(addrsel_policytab)
1081 init_policy_queue(void)
1084 TAILQ_INIT(&V_addrsel_policytab);
1088 add_addrsel_policyent(struct in6_addrpolicy *newpolicy)
1090 struct addrsel_policyent *new, *pol;
1092 new = malloc(sizeof(*new), M_IFADDR,
1097 /* duplication check */
1098 TAILQ_FOREACH(pol, &V_addrsel_policytab, ape_entry) {
1099 if (IN6_ARE_ADDR_EQUAL(&newpolicy->addr.sin6_addr,
1100 &pol->ape_policy.addr.sin6_addr) &&
1101 IN6_ARE_ADDR_EQUAL(&newpolicy->addrmask.sin6_addr,
1102 &pol->ape_policy.addrmask.sin6_addr)) {
1105 free(new, M_IFADDR);
1106 return (EEXIST); /* or override it? */
1110 bzero(new, sizeof(*new));
1112 /* XXX: should validate entry */
1113 new->ape_policy = *newpolicy;
1115 TAILQ_INSERT_TAIL(&V_addrsel_policytab, new, ape_entry);
1123 delete_addrsel_policyent(struct in6_addrpolicy *key)
1125 struct addrsel_policyent *pol;
1130 /* search for the entry in the table */
1131 TAILQ_FOREACH(pol, &V_addrsel_policytab, ape_entry) {
1132 if (IN6_ARE_ADDR_EQUAL(&key->addr.sin6_addr,
1133 &pol->ape_policy.addr.sin6_addr) &&
1134 IN6_ARE_ADDR_EQUAL(&key->addrmask.sin6_addr,
1135 &pol->ape_policy.addrmask.sin6_addr)) {
1145 TAILQ_REMOVE(&V_addrsel_policytab, pol, ape_entry);
1148 free(pol, M_IFADDR);
1154 walk_addrsel_policy(int (*callback)(struct in6_addrpolicy *, void *), void *w)
1156 struct addrsel_policyent *pol;
1160 TAILQ_FOREACH(pol, &V_addrsel_policytab, ape_entry) {
1161 if ((error = (*callback)(&pol->ape_policy, w)) != 0) {
1171 dump_addrsel_policyent(struct in6_addrpolicy *pol, void *arg)
1174 struct walkarg *w = arg;
1176 error = SYSCTL_OUT(w->w_req, pol, sizeof(*pol));
1181 static struct in6_addrpolicy *
1182 match_addrsel_policy(struct sockaddr_in6 *key)
1184 struct addrsel_policyent *pent;
1185 struct in6_addrpolicy *bestpol = NULL, *pol;
1186 int matchlen, bestmatchlen = -1;
1187 u_char *mp, *ep, *k, *p, m;
1189 TAILQ_FOREACH(pent, &V_addrsel_policytab, ape_entry) {
1192 pol = &pent->ape_policy;
1193 mp = (u_char *)&pol->addrmask.sin6_addr;
1194 ep = mp + 16; /* XXX: scope field? */
1195 k = (u_char *)&key->sin6_addr;
1196 p = (u_char *)&pol->addr.sin6_addr;
1197 for (; mp < ep && *mp; mp++, k++, p++) {
1200 goto next; /* not match */
1201 if (m == 0xff) /* short cut for a typical case */
1211 /* matched. check if this is better than the current best. */
1212 if (bestpol == NULL ||
1213 matchlen > bestmatchlen) {
1215 bestmatchlen = matchlen;