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 "opt_mpath.h"
72 #include <sys/param.h>
73 #include <sys/systm.h>
75 #include <sys/malloc.h>
78 #include <sys/protosw.h>
79 #include <sys/socket.h>
80 #include <sys/socketvar.h>
81 #include <sys/sockio.h>
82 #include <sys/sysctl.h>
83 #include <sys/errno.h>
86 #include <sys/kernel.h>
87 #include <sys/rmlock.h>
91 #include <net/if_var.h>
92 #include <net/if_dl.h>
93 #include <net/route.h>
94 #include <net/route/nhop.h>
95 #include <net/if_llatbl.h>
97 #include <netinet/in.h>
98 #include <netinet/in_var.h>
99 #include <netinet/in_systm.h>
100 #include <netinet/ip.h>
101 #include <netinet/in_pcb.h>
102 #include <netinet/ip_var.h>
103 #include <netinet/udp.h>
104 #include <netinet/udp_var.h>
106 #include <netinet6/in6_var.h>
107 #include <netinet/ip6.h>
108 #include <netinet6/in6_fib.h>
109 #include <netinet6/in6_pcb.h>
110 #include <netinet6/ip6_var.h>
111 #include <netinet6/scope6_var.h>
112 #include <netinet6/nd6.h>
114 static struct mtx addrsel_lock;
115 #define ADDRSEL_LOCK_INIT() mtx_init(&addrsel_lock, "addrsel_lock", NULL, MTX_DEF)
116 #define ADDRSEL_LOCK() mtx_lock(&addrsel_lock)
117 #define ADDRSEL_UNLOCK() mtx_unlock(&addrsel_lock)
118 #define ADDRSEL_LOCK_ASSERT() mtx_assert(&addrsel_lock, MA_OWNED)
120 static struct sx addrsel_sxlock;
121 #define ADDRSEL_SXLOCK_INIT() sx_init(&addrsel_sxlock, "addrsel_sxlock")
122 #define ADDRSEL_SLOCK() sx_slock(&addrsel_sxlock)
123 #define ADDRSEL_SUNLOCK() sx_sunlock(&addrsel_sxlock)
124 #define ADDRSEL_XLOCK() sx_xlock(&addrsel_sxlock)
125 #define ADDRSEL_XUNLOCK() sx_xunlock(&addrsel_sxlock)
127 #define ADDR_LABEL_NOTAPP (-1)
128 VNET_DEFINE_STATIC(struct in6_addrpolicy, defaultaddrpolicy);
129 #define V_defaultaddrpolicy VNET(defaultaddrpolicy)
131 VNET_DEFINE(int, ip6_prefer_tempaddr) = 0;
133 static int selectroute(struct sockaddr_in6 *, struct ip6_pktopts *,
134 struct ip6_moptions *, struct route_in6 *, struct ifnet **,
135 struct nhop_object **, int, u_int, uint32_t);
136 static int in6_selectif(struct sockaddr_in6 *, struct ip6_pktopts *,
137 struct ip6_moptions *, struct ifnet **,
138 struct ifnet *, u_int);
139 static int in6_selectsrc(uint32_t, struct sockaddr_in6 *,
140 struct ip6_pktopts *, struct inpcb *, struct ucred *,
141 struct ifnet **, struct in6_addr *);
143 static struct in6_addrpolicy *lookup_addrsel_policy(struct sockaddr_in6 *);
145 static void init_policy_queue(void);
146 static int add_addrsel_policyent(struct in6_addrpolicy *);
147 static int delete_addrsel_policyent(struct in6_addrpolicy *);
148 static int walk_addrsel_policy(int (*)(struct in6_addrpolicy *, void *),
150 static int dump_addrsel_policyent(struct in6_addrpolicy *, void *);
151 static struct in6_addrpolicy *match_addrsel_policy(struct sockaddr_in6 *);
154 * Return an IPv6 address, which is the most appropriate for a given
155 * destination and user specified options.
156 * If necessary, this function lookups the routing table and returns
157 * an entry to the caller for later use.
159 #define REPLACE(r) do {\
160 IP6STAT_INC(ip6s_sources_rule[(r)]); \
162 char ip6buf[INET6_ADDRSTRLEN], ip6b[INET6_ADDRSTRLEN]; \
163 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)); \
167 #define NEXT(r) do {\
169 char ip6buf[INET6_ADDRSTRLEN], ip6b[INET6_ADDRSTRLEN]; \
170 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)); \
172 goto next; /* XXX: we can't use 'continue' here */ \
174 #define BREAK(r) do { \
175 IP6STAT_INC(ip6s_sources_rule[(r)]); \
176 goto out; /* XXX: we can't use 'break' here */ \
180 in6_selectsrc(uint32_t fibnum, struct sockaddr_in6 *dstsock,
181 struct ip6_pktopts *opts, struct inpcb *inp, struct ucred *cred,
182 struct ifnet **ifpp, struct in6_addr *srcp)
184 struct rm_priotracker in6_ifa_tracker;
185 struct in6_addr dst, tmp;
186 struct ifnet *ifp = NULL, *oifp = NULL;
187 struct in6_ifaddr *ia = NULL, *ia_best = NULL;
188 struct in6_pktinfo *pi = NULL;
189 int dst_scope = -1, best_scope = -1, best_matchlen = -1;
190 struct in6_addrpolicy *dst_policy = NULL, *best_policy = NULL;
194 struct ip6_moptions *mopts;
196 KASSERT(srcp != NULL, ("%s: srcp is NULL", __func__));
198 dst = dstsock->sin6_addr; /* make a copy for local operation */
201 * Save a possibly passed in ifp for in6_selectsrc. Only
202 * neighbor discovery code should use this feature, where
203 * we may know the interface but not the FIB number holding
204 * the connected subnet in case someone deleted it from the
205 * default FIB and we need to check the interface.
213 INP_LOCK_ASSERT(inp);
214 mopts = inp->in6p_moptions;
220 * If the source address is explicitly specified by the caller,
221 * check if the requested source address is indeed a unicast address
222 * assigned to the node, and can be used as the packet's source
223 * address. If everything is okay, use the address as source.
225 if (opts && (pi = opts->ip6po_pktinfo) &&
226 !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) {
227 /* get the outgoing interface */
228 if ((error = in6_selectif(dstsock, opts, mopts, &ifp, oifp,
234 * determine the appropriate zone id of the source based on
235 * the zone of the destination and the outgoing interface.
236 * If the specified address is ambiguous wrt the scope zone,
237 * the interface must be specified; otherwise, ifa_ifwithaddr()
238 * will fail matching the address.
242 error = in6_setscope(&tmp, ifp, &odstzone);
246 if (cred != NULL && (error = prison_local_ip6(cred,
247 &tmp, (inp->inp_flags & IN6P_IPV6_V6ONLY) != 0)) != 0)
251 * If IPV6_BINDANY socket option is set, we allow to specify
252 * non local addresses as source address in IPV6_PKTINFO
255 if ((inp->inp_flags & INP_BINDANY) == 0) {
256 ia = in6ifa_ifwithaddr(&tmp, 0 /* XXX */);
257 if (ia == NULL || (ia->ia6_flags & (IN6_IFF_ANYCAST |
258 IN6_IFF_NOTREADY))) {
260 ifa_free(&ia->ia_ifa);
261 return (EADDRNOTAVAIL);
263 bcopy(&ia->ia_addr.sin6_addr, srcp, sizeof(*srcp));
264 ifa_free(&ia->ia_ifa);
266 bcopy(&tmp, srcp, sizeof(*srcp));
267 pi->ipi6_addr = tmp; /* XXX: this overrides pi */
274 * Otherwise, if the socket has already bound the source, just use it.
276 if (inp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
278 (error = prison_local_ip6(cred, &inp->in6p_laddr,
279 ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0))) != 0)
281 bcopy(&inp->in6p_laddr, srcp, sizeof(*srcp));
286 * Bypass source address selection and use the primary jail IP
289 if (cred != NULL && !prison_saddrsel_ip6(cred, srcp))
293 * If the address is not specified, choose the best one based on
294 * the outgoing interface and the destination address.
296 /* get the outgoing interface */
297 if ((error = in6_selectif(dstsock, opts, mopts, &ifp, oifp,
298 (inp != NULL) ? inp->inp_inc.inc_fibnum : fibnum)) != 0)
302 if (ifp == NULL) /* this should not happen */
303 panic("in6_selectsrc: NULL ifp");
305 error = in6_setscope(&dst, ifp, &odstzone);
309 IN6_IFADDR_RLOCK(&in6_ifa_tracker);
310 CK_STAILQ_FOREACH(ia, &V_in6_ifaddrhead, ia_link) {
311 int new_scope = -1, new_matchlen = -1;
312 struct in6_addrpolicy *new_policy = NULL;
313 u_int32_t srczone, osrczone, dstzone;
315 struct ifnet *ifp1 = ia->ia_ifp;
318 * We'll never take an address that breaks the scope zone
319 * of the destination. We also skip an address if its zone
320 * does not contain the outgoing interface.
321 * XXX: we should probably use sin6_scope_id here.
323 if (in6_setscope(&dst, ifp1, &dstzone) ||
324 odstzone != dstzone) {
327 src = ia->ia_addr.sin6_addr;
328 if (in6_setscope(&src, ifp, &osrczone) ||
329 in6_setscope(&src, ifp1, &srczone) ||
330 osrczone != srczone) {
334 /* avoid unusable addresses */
336 (IN6_IFF_NOTREADY | IN6_IFF_ANYCAST | IN6_IFF_DETACHED))) {
339 if (!V_ip6_use_deprecated && IFA6_IS_DEPRECATED(ia))
342 /* If jailed only take addresses of the jail into account. */
344 prison_check_ip6(cred, &ia->ia_addr.sin6_addr) != 0)
347 /* Rule 1: Prefer same address */
348 if (IN6_ARE_ADDR_EQUAL(&dst, &ia->ia_addr.sin6_addr)) {
350 BREAK(1); /* there should be no better candidate */
356 /* Rule 2: Prefer appropriate scope */
358 dst_scope = in6_addrscope(&dst);
359 new_scope = in6_addrscope(&ia->ia_addr.sin6_addr);
360 if (IN6_ARE_SCOPE_CMP(best_scope, new_scope) < 0) {
361 if (IN6_ARE_SCOPE_CMP(best_scope, dst_scope) < 0)
364 } else if (IN6_ARE_SCOPE_CMP(new_scope, best_scope) < 0) {
365 if (IN6_ARE_SCOPE_CMP(new_scope, dst_scope) < 0)
371 * Rule 3: Avoid deprecated addresses. Note that the case of
372 * !ip6_use_deprecated is already rejected above.
374 if (!IFA6_IS_DEPRECATED(ia_best) && IFA6_IS_DEPRECATED(ia))
376 if (IFA6_IS_DEPRECATED(ia_best) && !IFA6_IS_DEPRECATED(ia))
379 /* Rule 4: Prefer home addresses */
381 * XXX: This is a TODO. We should probably merge the MIP6
385 /* Rule 5: Prefer outgoing interface */
386 if (!(ND_IFINFO(ifp)->flags & ND6_IFF_NO_PREFER_IFACE)) {
387 if (ia_best->ia_ifp == ifp && ia->ia_ifp != ifp)
389 if (ia_best->ia_ifp != ifp && ia->ia_ifp == ifp)
394 * Rule 6: Prefer matching label
395 * Note that best_policy should be non-NULL here.
397 if (dst_policy == NULL)
398 dst_policy = lookup_addrsel_policy(dstsock);
399 if (dst_policy->label != ADDR_LABEL_NOTAPP) {
400 new_policy = lookup_addrsel_policy(&ia->ia_addr);
401 if (dst_policy->label == best_policy->label &&
402 dst_policy->label != new_policy->label)
404 if (dst_policy->label != best_policy->label &&
405 dst_policy->label == new_policy->label)
410 * Rule 7: Prefer public addresses.
411 * We allow users to reverse the logic by configuring
412 * a sysctl variable, so that privacy conscious users can
413 * always prefer temporary addresses.
416 opts->ip6po_prefer_tempaddr == IP6PO_TEMPADDR_SYSTEM) {
417 prefer_tempaddr = V_ip6_prefer_tempaddr;
418 } else if (opts->ip6po_prefer_tempaddr ==
419 IP6PO_TEMPADDR_NOTPREFER) {
423 if (!(ia_best->ia6_flags & IN6_IFF_TEMPORARY) &&
424 (ia->ia6_flags & IN6_IFF_TEMPORARY)) {
430 if ((ia_best->ia6_flags & IN6_IFF_TEMPORARY) &&
431 !(ia->ia6_flags & IN6_IFF_TEMPORARY)) {
439 * Rule 8: prefer addresses on alive interfaces.
440 * This is a KAME specific rule.
442 if ((ia_best->ia_ifp->if_flags & IFF_UP) &&
443 !(ia->ia_ifp->if_flags & IFF_UP))
445 if (!(ia_best->ia_ifp->if_flags & IFF_UP) &&
446 (ia->ia_ifp->if_flags & IFF_UP))
450 * Rule 9: prefer address with better virtual status.
452 if (ifa_preferred(&ia_best->ia_ifa, &ia->ia_ifa))
454 if (ifa_preferred(&ia->ia_ifa, &ia_best->ia_ifa))
458 * Rule 10: prefer address with `prefer_source' flag.
460 if ((ia_best->ia6_flags & IN6_IFF_PREFER_SOURCE) == 0 &&
461 (ia->ia6_flags & IN6_IFF_PREFER_SOURCE) != 0)
463 if ((ia_best->ia6_flags & IN6_IFF_PREFER_SOURCE) != 0 &&
464 (ia->ia6_flags & IN6_IFF_PREFER_SOURCE) == 0)
468 * Rule 14: Use longest matching prefix.
469 * Note: in the address selection draft, this rule is
470 * documented as "Rule 8". However, since it is also
471 * documented that this rule can be overridden, we assign
472 * a large number so that it is easy to assign smaller numbers
473 * to more preferred rules.
475 new_matchlen = in6_matchlen(&ia->ia_addr.sin6_addr, &dst);
476 if (best_matchlen < new_matchlen)
478 if (new_matchlen < best_matchlen)
481 /* Rule 15 is reserved. */
484 * Last resort: just keep the current candidate.
485 * Or, do we need more rules?
491 best_scope = (new_scope >= 0 ? new_scope :
492 in6_addrscope(&ia_best->ia_addr.sin6_addr));
493 best_policy = (new_policy ? new_policy :
494 lookup_addrsel_policy(&ia_best->ia_addr));
495 best_matchlen = (new_matchlen >= 0 ? new_matchlen :
496 in6_matchlen(&ia_best->ia_addr.sin6_addr,
506 if ((ia = ia_best) == NULL) {
507 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
508 IP6STAT_INC(ip6s_sources_none);
509 return (EADDRNOTAVAIL);
513 * At this point at least one of the addresses belonged to the jail
514 * but it could still be, that we want to further restrict it, e.g.
515 * theoratically IN6_IS_ADDR_LOOPBACK.
516 * It must not be IN6_IS_ADDR_UNSPECIFIED anymore.
517 * prison_local_ip6() will fix an IN6_IS_ADDR_LOOPBACK but should
518 * let all others previously selected pass.
519 * Use tmp to not change ::1 on lo0 to the primary jail address.
521 tmp = ia->ia_addr.sin6_addr;
522 if (cred != NULL && prison_local_ip6(cred, &tmp, (inp != NULL &&
523 (inp->inp_flags & IN6P_IPV6_V6ONLY) != 0)) != 0) {
524 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
525 IP6STAT_INC(ip6s_sources_none);
526 return (EADDRNOTAVAIL);
532 bcopy(&tmp, srcp, sizeof(*srcp));
533 if (ia->ia_ifp == ifp)
534 IP6STAT_INC(ip6s_sources_sameif[best_scope]);
536 IP6STAT_INC(ip6s_sources_otherif[best_scope]);
537 if (dst_scope == best_scope)
538 IP6STAT_INC(ip6s_sources_samescope[best_scope]);
540 IP6STAT_INC(ip6s_sources_otherscope[best_scope]);
541 if (IFA6_IS_DEPRECATED(ia))
542 IP6STAT_INC(ip6s_sources_deprecated[best_scope]);
543 IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
548 * Select source address based on @inp, @dstsock and @opts.
549 * Stores selected address to @srcp. If @scope_ambiguous is set,
550 * embed scope from selected outgoing interface. If @hlim pointer
551 * is provided, stores calculated hop limit there.
552 * Returns 0 on success.
555 in6_selectsrc_socket(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
556 struct inpcb *inp, struct ucred *cred, int scope_ambiguous,
557 struct in6_addr *srcp, int *hlim)
559 struct ifnet *retifp;
563 fibnum = inp->inp_inc.inc_fibnum;
566 error = in6_selectsrc(fibnum, dstsock, opts, inp, cred, &retifp, srcp);
571 *hlim = in6_selecthlim(inp, retifp);
573 if (retifp == NULL || scope_ambiguous == 0)
577 * Application should provide a proper zone ID or the use of
578 * default zone IDs should be enabled. Unfortunately, some
579 * applications do not behave as it should, so we need a
580 * workaround. Even if an appropriate ID is not determined
581 * (when it's required), if we can determine the outgoing
582 * interface. determine the zone ID based on the interface.
584 error = in6_setscope(&dstsock->sin6_addr, retifp, NULL);
590 * Select source address based on @fibnum, @dst and @scopeid.
591 * Stores selected address to @srcp.
592 * Returns 0 on success.
594 * Used by non-socket based consumers (ND code mostly)
597 in6_selectsrc_addr(uint32_t fibnum, const struct in6_addr *dst,
598 uint32_t scopeid, struct ifnet *ifp, struct in6_addr *srcp,
601 struct ifnet *retifp;
602 struct sockaddr_in6 dst_sa;
606 bzero(&dst_sa, sizeof(dst_sa));
607 dst_sa.sin6_family = AF_INET6;
608 dst_sa.sin6_len = sizeof(dst_sa);
609 dst_sa.sin6_addr = *dst;
610 dst_sa.sin6_scope_id = scopeid;
611 sa6_embedscope(&dst_sa, 0);
613 error = in6_selectsrc(fibnum, &dst_sa, NULL, NULL, NULL, &retifp, srcp);
615 *hlim = in6_selecthlim(NULL, retifp);
621 * clone - meaningful only for bsdi and freebsd
624 selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
625 struct ip6_moptions *mopts, struct route_in6 *ro,
626 struct ifnet **retifp, struct nhop_object **retnh, int norouteok,
627 u_int fibnum, uint32_t flowid)
630 struct ifnet *ifp = NULL;
631 struct nhop_object *nh = NULL;
632 struct sockaddr_in6 *sin6_next;
633 struct in6_pktinfo *pi = NULL;
634 struct in6_addr *dst = &dstsock->sin6_addr;
637 char ip6buf[INET6_ADDRSTRLEN];
639 if (dstsock->sin6_addr.s6_addr32[0] == 0 &&
640 dstsock->sin6_addr.s6_addr32[1] == 0 &&
641 !IN6_IS_ADDR_LOOPBACK(&dstsock->sin6_addr)) {
642 printf("%s: strange destination %s\n", __func__,
643 ip6_sprintf(ip6buf, &dstsock->sin6_addr));
645 printf("%s: destination = %s%%%d\n", __func__,
646 ip6_sprintf(ip6buf, &dstsock->sin6_addr),
647 dstsock->sin6_scope_id); /* for debug */
651 /* If the caller specify the outgoing interface explicitly, use it. */
652 if (opts && (pi = opts->ip6po_pktinfo) != NULL && pi->ipi6_ifindex) {
653 /* XXX boundary check is assumed to be already done. */
654 ifp = ifnet_byindex(pi->ipi6_ifindex);
656 (norouteok || retnh == NULL ||
657 IN6_IS_ADDR_MULTICAST(dst))) {
659 * we do not have to check or get the route for
667 * If the destination address is a multicast address and the outgoing
668 * interface for the address is specified by the caller, use it.
670 if (IN6_IS_ADDR_MULTICAST(dst) &&
671 mopts != NULL && (ifp = mopts->im6o_multicast_ifp) != NULL) {
672 goto done; /* we do not need a route for multicast. */
675 * If destination address is LLA or link- or node-local multicast,
676 * use it's embedded scope zone id to determine outgoing interface.
678 if (IN6_IS_ADDR_MC_LINKLOCAL(dst) ||
679 IN6_IS_ADDR_MC_NODELOCAL(dst)) {
680 zoneid = ntohs(in6_getscope(dst));
682 ifp = in6_getlinkifnet(zoneid);
689 * If the next hop address for the packet is specified by the caller,
690 * use it as the gateway.
692 if (opts && opts->ip6po_nexthop) {
693 struct route_in6 *ron;
695 sin6_next = satosin6(opts->ip6po_nexthop);
696 if (IN6_IS_ADDR_LINKLOCAL(&sin6_next->sin6_addr)) {
698 * Next hop is LLA, thus it should be neighbor.
699 * Determine outgoing interface by zone index.
701 zoneid = ntohs(in6_getscope(&sin6_next->sin6_addr));
703 ifp = in6_getlinkifnet(zoneid);
707 ron = &opts->ip6po_nextroute;
708 /* Use a cached route if it exists and is valid. */
709 if (ron->ro_nh != NULL && (
710 !NH_IS_VALID(ron->ro_nh) ||
711 ron->ro_dst.sin6_family != AF_INET6 ||
712 !IN6_ARE_ADDR_EQUAL(&ron->ro_dst.sin6_addr,
713 &sin6_next->sin6_addr)))
715 if (ron->ro_nh == NULL) {
716 ron->ro_dst = *sin6_next;
718 * sin6_next is not link-local OR scopeid is 0,
719 * no need to clear scope
721 ron->ro_nh = fib6_lookup(fibnum,
722 &sin6_next->sin6_addr, 0, NHR_REF, flowid);
725 * The node identified by that address must be a
726 * neighbor of the sending host.
728 if (ron->ro_nh == NULL ||
729 (ron->ro_nh->nh_flags & NHF_GATEWAY) != 0)
730 error = EHOSTUNREACH;
739 * Use a cached route if it exists and is valid, else try to allocate
740 * a new one. Note that we should check the address family of the
741 * cached destination, in case of sharing the cache with IPv4.
745 (!NH_IS_VALID(ro->ro_nh) ||
746 ((struct sockaddr *)(&ro->ro_dst))->sa_family != AF_INET6 ||
747 !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr,
751 if (ro->ro_nh == (struct nhop_object *)NULL) {
752 struct sockaddr_in6 *sa6;
754 /* No route yet, so try to acquire one */
755 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6));
756 sa6 = (struct sockaddr_in6 *)&ro->ro_dst;
758 sa6->sin6_scope_id = 0;
761 * Currently dst has scopeid embedded iff it is LL.
762 * New routing API accepts scopeid as a separate argument.
763 * Convert dst before/after doing lookup
765 uint32_t scopeid = 0;
766 if (IN6_IS_SCOPE_LINKLOCAL(&sa6->sin6_addr)) {
767 /* Unwrap in6_getscope() and in6_clearscope() */
768 scopeid = ntohs(sa6->sin6_addr.s6_addr16[1]);
769 sa6->sin6_addr.s6_addr16[1] = 0;
773 ro->ro_nh = fib6_lookup(fibnum,
774 &sa6->sin6_addr, scopeid, NHR_REF, flowid);
776 if (IN6_IS_SCOPE_LINKLOCAL(&sa6->sin6_addr))
777 sa6->sin6_addr.s6_addr16[1] = htons(scopeid);
781 * do not care about the result if we have the nexthop
782 * explicitly specified.
784 if (opts && opts->ip6po_nexthop)
788 ifp = ro->ro_nh->nh_ifp;
790 error = EHOSTUNREACH;
794 * Check if the outgoing interface conflicts with
795 * the interface specified by ipi6_ifindex (if specified).
796 * Note that loopback interface is always okay.
797 * (this may happen when we are sending a packet to one of
798 * our own addresses.)
800 if (ifp && opts && opts->ip6po_pktinfo &&
801 opts->ip6po_pktinfo->ipi6_ifindex) {
802 if (!(ifp->if_flags & IFF_LOOPBACK) &&
804 opts->ip6po_pktinfo->ipi6_ifindex) {
805 error = EHOSTUNREACH;
812 if (ifp == NULL && nh == NULL) {
814 * This can happen if the caller did not pass a cached route
815 * nor any other hints. We treat this case an error.
817 error = EHOSTUNREACH;
819 if (error == EHOSTUNREACH)
820 IP6STAT_INC(ip6s_noroute);
822 if (retifp != NULL) {
824 *retifp = nh->nh_aifp;
830 *retnh = nh; /* nh may be NULL */
836 in6_selectif(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
837 struct ip6_moptions *mopts, struct ifnet **retifp,
838 struct ifnet *oifp, u_int fibnum)
841 struct route_in6 sro;
842 struct nhop_object *nh = NULL;
845 KASSERT(retifp != NULL, ("%s: retifp is NULL", __func__));
847 bzero(&sro, sizeof(sro));
850 error = selectroute(dstsock, opts, mopts, &sro, retifp, &nh, 1, fibnum, 0);
853 nh_flags = nh->nh_flags;
854 if (nh != NULL && nh == sro.ro_nh)
858 /* Help ND. See oifp comment in in6_selectsrc(). */
859 if (oifp != NULL && fibnum == RT_DEFAULT_FIB) {
867 * do not use a rejected or black hole route.
868 * XXX: this check should be done in the L2 output routine.
869 * However, if we skipped this check here, we'd see the following
871 * - install a rejected route for a scoped address prefix
873 * - send a packet to a destination that matches the scoped prefix,
874 * with ambiguity about the scope zone.
875 * - pick the outgoing interface from the route, and disambiguate the
876 * scope zone with the interface.
877 * - ip6_output() would try to get another route with the "new"
878 * destination, which may be valid.
879 * - we'd see no error on output.
880 * Although this may not be very harmful, it should still be confusing.
881 * We thus reject the case here.
884 if (nh_flags & (NHF_REJECT | NHF_BLACKHOLE)) {
885 error = (nh_flags & NHF_HOST ? EHOSTUNREACH : ENETUNREACH);
892 /* Public wrapper function to selectroute(). */
894 in6_selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
895 struct ip6_moptions *mopts, struct route_in6 *ro,
896 struct ifnet **retifp, struct nhop_object **retnh, u_int fibnum, uint32_t flowid)
899 return (selectroute(dstsock, opts, mopts, ro, retifp,
900 retnh, 0, fibnum, flowid));
904 * Default hop limit selection. The precedence is as follows:
905 * 1. Hoplimit value specified via ioctl.
906 * 2. (If the outgoing interface is detected) the current
907 * hop limit of the interface specified by router advertisement.
908 * 3. The system default hoplimit.
911 in6_selecthlim(struct inpcb *inp, struct ifnet *ifp)
914 if (inp && inp->in6p_hops >= 0)
915 return (inp->in6p_hops);
917 return (ND_IFINFO(ifp)->chlim);
918 else if (inp && !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
919 struct nhop_object *nh;
921 uint32_t fibnum, scopeid;
924 fibnum = inp->inp_inc.inc_fibnum;
925 in6_splitscope(&inp->in6p_faddr, &dst, &scopeid);
926 nh = fib6_lookup(fibnum, &dst, scopeid, 0, 0);
928 hlim = ND_IFINFO(nh->nh_ifp)->chlim;
932 return (V_ip6_defhlim);
936 * XXX: this is borrowed from in6_pcbbind(). If possible, we should
937 * share this function by all *bsd*...
940 in6_pcbsetport(struct in6_addr *laddr, struct inpcb *inp, struct ucred *cred)
942 struct socket *so = inp->inp_socket;
944 int error, lookupflags = 0;
946 struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
949 INP_WLOCK_ASSERT(inp);
950 INP_HASH_WLOCK_ASSERT(pcbinfo);
952 error = prison_local_ip6(cred, laddr,
953 ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0));
957 /* XXX: this is redundant when called from in6_pcbbind */
958 if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT|SO_REUSEPORT_LB)) == 0)
959 lookupflags = INPLOOKUP_WILDCARD;
961 inp->inp_flags |= INP_ANONPORT;
963 error = in_pcb_lport(inp, NULL, &lport, cred, lookupflags);
967 inp->inp_lport = lport;
968 if (in_pcbinshash(inp) != 0) {
969 inp->in6p_laddr = in6addr_any;
978 addrsel_policy_init(void)
983 /* initialize the "last resort" policy */
984 bzero(&V_defaultaddrpolicy, sizeof(V_defaultaddrpolicy));
985 V_defaultaddrpolicy.label = ADDR_LABEL_NOTAPP;
987 if (!IS_DEFAULT_VNET(curvnet))
991 ADDRSEL_SXLOCK_INIT();
994 static struct in6_addrpolicy *
995 lookup_addrsel_policy(struct sockaddr_in6 *key)
997 struct in6_addrpolicy *match = NULL;
1000 match = match_addrsel_policy(key);
1003 match = &V_defaultaddrpolicy;
1012 * Subroutines to manage the address selection policy table via sysctl.
1015 struct sysctl_req *w_req;
1018 static int in6_src_sysctl(SYSCTL_HANDLER_ARGS);
1019 SYSCTL_DECL(_net_inet6_ip6);
1020 static SYSCTL_NODE(_net_inet6_ip6, IPV6CTL_ADDRCTLPOLICY, addrctlpolicy,
1021 CTLFLAG_RD | CTLFLAG_MPSAFE, in6_src_sysctl,
1025 in6_src_sysctl(SYSCTL_HANDLER_ARGS)
1032 bzero(&w, sizeof(w));
1035 return (walk_addrsel_policy(dump_addrsel_policyent, &w));
1039 in6_src_ioctl(u_long cmd, caddr_t data)
1041 struct in6_addrpolicy ent0;
1043 if (cmd != SIOCAADDRCTL_POLICY && cmd != SIOCDADDRCTL_POLICY)
1044 return (EOPNOTSUPP); /* check for safety */
1046 ent0 = *(struct in6_addrpolicy *)data;
1048 if (ent0.label == ADDR_LABEL_NOTAPP)
1050 /* check if the prefix mask is consecutive. */
1051 if (in6_mask2len(&ent0.addrmask.sin6_addr, NULL) < 0)
1053 /* clear trailing garbages (if any) of the prefix address. */
1054 IN6_MASK_ADDR(&ent0.addr.sin6_addr, &ent0.addrmask.sin6_addr);
1058 case SIOCAADDRCTL_POLICY:
1059 return (add_addrsel_policyent(&ent0));
1060 case SIOCDADDRCTL_POLICY:
1061 return (delete_addrsel_policyent(&ent0));
1064 return (0); /* XXX: compromise compilers */
1068 * The followings are implementation of the policy table using a
1069 * simple tail queue.
1070 * XXX such details should be hidden.
1071 * XXX implementation using binary tree should be more efficient.
1073 struct addrsel_policyent {
1074 TAILQ_ENTRY(addrsel_policyent) ape_entry;
1075 struct in6_addrpolicy ape_policy;
1078 TAILQ_HEAD(addrsel_policyhead, addrsel_policyent);
1080 VNET_DEFINE_STATIC(struct addrsel_policyhead, addrsel_policytab);
1081 #define V_addrsel_policytab VNET(addrsel_policytab)
1084 init_policy_queue(void)
1087 TAILQ_INIT(&V_addrsel_policytab);
1091 add_addrsel_policyent(struct in6_addrpolicy *newpolicy)
1093 struct addrsel_policyent *new, *pol;
1095 new = malloc(sizeof(*new), M_IFADDR,
1100 /* duplication check */
1101 TAILQ_FOREACH(pol, &V_addrsel_policytab, ape_entry) {
1102 if (IN6_ARE_ADDR_EQUAL(&newpolicy->addr.sin6_addr,
1103 &pol->ape_policy.addr.sin6_addr) &&
1104 IN6_ARE_ADDR_EQUAL(&newpolicy->addrmask.sin6_addr,
1105 &pol->ape_policy.addrmask.sin6_addr)) {
1108 free(new, M_IFADDR);
1109 return (EEXIST); /* or override it? */
1113 bzero(new, sizeof(*new));
1115 /* XXX: should validate entry */
1116 new->ape_policy = *newpolicy;
1118 TAILQ_INSERT_TAIL(&V_addrsel_policytab, new, ape_entry);
1126 delete_addrsel_policyent(struct in6_addrpolicy *key)
1128 struct addrsel_policyent *pol;
1133 /* search for the entry in the table */
1134 TAILQ_FOREACH(pol, &V_addrsel_policytab, ape_entry) {
1135 if (IN6_ARE_ADDR_EQUAL(&key->addr.sin6_addr,
1136 &pol->ape_policy.addr.sin6_addr) &&
1137 IN6_ARE_ADDR_EQUAL(&key->addrmask.sin6_addr,
1138 &pol->ape_policy.addrmask.sin6_addr)) {
1148 TAILQ_REMOVE(&V_addrsel_policytab, pol, ape_entry);
1151 free(pol, M_IFADDR);
1157 walk_addrsel_policy(int (*callback)(struct in6_addrpolicy *, void *), void *w)
1159 struct addrsel_policyent *pol;
1163 TAILQ_FOREACH(pol, &V_addrsel_policytab, ape_entry) {
1164 if ((error = (*callback)(&pol->ape_policy, w)) != 0) {
1174 dump_addrsel_policyent(struct in6_addrpolicy *pol, void *arg)
1177 struct walkarg *w = arg;
1179 error = SYSCTL_OUT(w->w_req, pol, sizeof(*pol));
1184 static struct in6_addrpolicy *
1185 match_addrsel_policy(struct sockaddr_in6 *key)
1187 struct addrsel_policyent *pent;
1188 struct in6_addrpolicy *bestpol = NULL, *pol;
1189 int matchlen, bestmatchlen = -1;
1190 u_char *mp, *ep, *k, *p, m;
1192 TAILQ_FOREACH(pent, &V_addrsel_policytab, ape_entry) {
1195 pol = &pent->ape_policy;
1196 mp = (u_char *)&pol->addrmask.sin6_addr;
1197 ep = mp + 16; /* XXX: scope field? */
1198 k = (u_char *)&key->sin6_addr;
1199 p = (u_char *)&pol->addr.sin6_addr;
1200 for (; mp < ep && *mp; mp++, k++, p++) {
1203 goto next; /* not match */
1204 if (m == 0xff) /* short cut for a typical case */
1214 /* matched. check if this is better than the current best. */
1215 if (bestpol == NULL ||
1216 matchlen > bestmatchlen) {
1218 bestmatchlen = matchlen;