2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
29 * $KAME: in6_src.c,v 1.132 2003/08/26 04:42:27 keiichi Exp $
33 * Copyright (c) 1982, 1986, 1991, 1993
34 * The Regents of the University of California. All rights reserved.
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
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.
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
60 * @(#)in_pcb.c 8.2 (Berkeley) 1/4/94
63 #include <sys/cdefs.h>
64 __FBSDID("$FreeBSD$");
67 #include "opt_inet6.h"
68 #include "opt_mpath.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>
86 #include <sys/vimage.h>
89 #include <net/route.h>
90 #include <net/if_llatbl.h>
92 #include <net/radix_mpath.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>
103 #include <netinet/vinet.h>
105 #include <netinet6/in6_var.h>
106 #include <netinet/ip6.h>
107 #include <netinet6/in6_pcb.h>
108 #include <netinet6/ip6_var.h>
109 #include <netinet6/scope6_var.h>
110 #include <netinet6/nd6.h>
111 #include <netinet6/vinet6.h>
113 static struct mtx addrsel_lock;
114 #define ADDRSEL_LOCK_INIT() mtx_init(&addrsel_lock, "addrsel_lock", NULL, MTX_DEF)
115 #define ADDRSEL_LOCK() mtx_lock(&addrsel_lock)
116 #define ADDRSEL_UNLOCK() mtx_unlock(&addrsel_lock)
117 #define ADDRSEL_LOCK_ASSERT() mtx_assert(&addrsel_lock, MA_OWNED)
119 static struct sx addrsel_sxlock;
120 #define ADDRSEL_SXLOCK_INIT() sx_init(&addrsel_sxlock, "addrsel_sxlock")
121 #define ADDRSEL_SLOCK() sx_slock(&addrsel_sxlock)
122 #define ADDRSEL_SUNLOCK() sx_sunlock(&addrsel_sxlock)
123 #define ADDRSEL_XLOCK() sx_xlock(&addrsel_sxlock)
124 #define ADDRSEL_XUNLOCK() sx_xunlock(&addrsel_sxlock)
126 #define ADDR_LABEL_NOTAPP (-1)
128 #ifdef VIMAGE_GLOBALS
129 struct in6_addrpolicy defaultaddrpolicy;
130 int ip6_prefer_tempaddr;
133 static int selectroute __P((struct sockaddr_in6 *, struct ip6_pktopts *,
134 struct ip6_moptions *, struct route_in6 *, struct ifnet **,
135 struct rtentry **, int));
136 static int in6_selectif __P((struct sockaddr_in6 *, struct ip6_pktopts *,
137 struct ip6_moptions *, struct route_in6 *ro, struct ifnet **));
139 static struct in6_addrpolicy *lookup_addrsel_policy(struct sockaddr_in6 *);
141 static void init_policy_queue(void);
142 static int add_addrsel_policyent(struct in6_addrpolicy *);
143 static int delete_addrsel_policyent(struct in6_addrpolicy *);
144 static int walk_addrsel_policy __P((int (*)(struct in6_addrpolicy *, void *),
146 static int dump_addrsel_policyent(struct in6_addrpolicy *, void *);
147 static struct in6_addrpolicy *match_addrsel_policy(struct sockaddr_in6 *);
150 * Return an IPv6 address, which is the most appropriate for a given
151 * destination and user specified options.
152 * If necessary, this function lookups the routing table and returns
153 * an entry to the caller for later use.
155 #define REPLACE(r) do {\
156 if ((r) < sizeof(V_ip6stat.ip6s_sources_rule) / \
157 sizeof(V_ip6stat.ip6s_sources_rule[0])) /* check for safety */ \
158 V_ip6stat.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 {\
166 if ((r) < sizeof(V_ip6stat.ip6s_sources_rule) / \
167 sizeof(V_ip6stat.ip6s_sources_rule[0])) /* check for safety */ \
168 V_ip6stat.ip6s_sources_rule[(r)]++; \
170 char ip6buf[INET6_ADDRSTRLEN], ip6b[INET6_ADDRSTRLEN]; \
171 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)); \
173 goto next; /* XXX: we can't use 'continue' here */ \
175 #define BREAK(r) do { \
176 if ((r) < sizeof(V_ip6stat.ip6s_sources_rule) / \
177 sizeof(V_ip6stat.ip6s_sources_rule[0])) /* check for safety */ \
178 V_ip6stat.ip6s_sources_rule[(r)]++; \
179 goto out; /* XXX: we can't use 'break' here */ \
183 in6_selectsrc(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
184 struct inpcb *inp, struct route_in6 *ro, struct ucred *cred,
185 struct ifnet **ifpp, int *errorp)
187 INIT_VNET_INET6(curvnet);
189 struct ifnet *ifp = NULL;
190 struct in6_ifaddr *ia = NULL, *ia_best = NULL;
191 struct in6_pktinfo *pi = NULL;
192 int dst_scope = -1, best_scope = -1, best_matchlen = -1;
193 struct in6_addrpolicy *dst_policy = NULL, *best_policy = NULL;
196 struct ip6_moptions *mopts;
198 dst = dstsock->sin6_addr; /* make a copy for local operation */
204 INP_LOCK_ASSERT(inp);
205 mopts = inp->in6p_moptions;
211 * If the source address is explicitly specified by the caller,
212 * check if the requested source address is indeed a unicast address
213 * assigned to the node, and can be used as the packet's source
214 * address. If everything is okay, use the address as source.
216 if (opts && (pi = opts->ip6po_pktinfo) &&
217 !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) {
218 struct sockaddr_in6 srcsock;
219 struct in6_ifaddr *ia6;
221 /* get the outgoing interface */
222 if ((*errorp = in6_selectif(dstsock, opts, mopts, ro, &ifp))
228 * determine the appropriate zone id of the source based on
229 * the zone of the destination and the outgoing interface.
230 * If the specified address is ambiguous wrt the scope zone,
231 * the interface must be specified; otherwise, ifa_ifwithaddr()
232 * will fail matching the address.
234 bzero(&srcsock, sizeof(srcsock));
235 srcsock.sin6_family = AF_INET6;
236 srcsock.sin6_len = sizeof(srcsock);
237 srcsock.sin6_addr = pi->ipi6_addr;
239 *errorp = in6_setscope(&srcsock.sin6_addr, ifp, NULL);
243 if (cred != NULL && (*errorp = prison_local_ip6(cred,
244 &srcsock.sin6_addr, (inp != NULL &&
245 (inp->inp_flags & IN6P_IPV6_V6ONLY) != 0))) != 0)
248 ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)(&srcsock));
250 (ia6->ia6_flags & (IN6_IFF_ANYCAST | IN6_IFF_NOTREADY))) {
251 *errorp = EADDRNOTAVAIL;
254 pi->ipi6_addr = srcsock.sin6_addr; /* XXX: this overrides pi */
257 return (&ia6->ia_addr.sin6_addr);
261 * Otherwise, if the socket has already bound the source, just use it.
263 if (inp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
265 (*errorp = prison_local_ip6(cred, &inp->in6p_laddr,
266 ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0))) != 0)
268 return (&inp->in6p_laddr);
272 * If the address is not specified, choose the best one based on
273 * the outgoing interface and the destination address.
275 /* get the outgoing interface */
276 if ((*errorp = in6_selectif(dstsock, opts, mopts, ro, &ifp)) != 0)
280 if (ifp == NULL) /* this should not happen */
281 panic("in6_selectsrc: NULL ifp");
283 *errorp = in6_setscope(&dst, ifp, &odstzone);
287 for (ia = V_in6_ifaddr; ia; ia = ia->ia_next) {
288 int new_scope = -1, new_matchlen = -1;
289 struct in6_addrpolicy *new_policy = NULL;
290 u_int32_t srczone, osrczone, dstzone;
292 struct ifnet *ifp1 = ia->ia_ifp;
295 * We'll never take an address that breaks the scope zone
296 * of the destination. We also skip an address if its zone
297 * does not contain the outgoing interface.
298 * XXX: we should probably use sin6_scope_id here.
300 if (in6_setscope(&dst, ifp1, &dstzone) ||
301 odstzone != dstzone) {
304 src = ia->ia_addr.sin6_addr;
305 if (in6_setscope(&src, ifp, &osrczone) ||
306 in6_setscope(&src, ifp1, &srczone) ||
307 osrczone != srczone) {
311 /* avoid unusable addresses */
313 (IN6_IFF_NOTREADY | IN6_IFF_ANYCAST | IN6_IFF_DETACHED))) {
316 if (!V_ip6_use_deprecated && IFA6_IS_DEPRECATED(ia))
320 prison_local_ip6(cred, &ia->ia_addr.sin6_addr,
322 (inp->inp_flags & IN6P_IPV6_V6ONLY) != 0)) != 0)
325 /* Rule 1: Prefer same address */
326 if (IN6_ARE_ADDR_EQUAL(&dst, &ia->ia_addr.sin6_addr)) {
328 BREAK(1); /* there should be no better candidate */
334 /* Rule 2: Prefer appropriate scope */
336 dst_scope = in6_addrscope(&dst);
337 new_scope = in6_addrscope(&ia->ia_addr.sin6_addr);
338 if (IN6_ARE_SCOPE_CMP(best_scope, new_scope) < 0) {
339 if (IN6_ARE_SCOPE_CMP(best_scope, dst_scope) < 0)
342 } else if (IN6_ARE_SCOPE_CMP(new_scope, best_scope) < 0) {
343 if (IN6_ARE_SCOPE_CMP(new_scope, dst_scope) < 0)
349 * Rule 3: Avoid deprecated addresses. Note that the case of
350 * !ip6_use_deprecated is already rejected above.
352 if (!IFA6_IS_DEPRECATED(ia_best) && IFA6_IS_DEPRECATED(ia))
354 if (IFA6_IS_DEPRECATED(ia_best) && !IFA6_IS_DEPRECATED(ia))
357 /* Rule 4: Prefer home addresses */
359 * XXX: This is a TODO. We should probably merge the MIP6
363 /* Rule 5: Prefer outgoing interface */
364 if (ia_best->ia_ifp == ifp && ia->ia_ifp != ifp)
366 if (ia_best->ia_ifp != ifp && ia->ia_ifp == ifp)
370 * Rule 6: Prefer matching label
371 * Note that best_policy should be non-NULL here.
373 if (dst_policy == NULL)
374 dst_policy = lookup_addrsel_policy(dstsock);
375 if (dst_policy->label != ADDR_LABEL_NOTAPP) {
376 new_policy = lookup_addrsel_policy(&ia->ia_addr);
377 if (dst_policy->label == best_policy->label &&
378 dst_policy->label != new_policy->label)
380 if (dst_policy->label != best_policy->label &&
381 dst_policy->label == new_policy->label)
386 * Rule 7: Prefer public addresses.
387 * We allow users to reverse the logic by configuring
388 * a sysctl variable, so that privacy conscious users can
389 * always prefer temporary addresses.
392 opts->ip6po_prefer_tempaddr == IP6PO_TEMPADDR_SYSTEM) {
393 prefer_tempaddr = V_ip6_prefer_tempaddr;
394 } else if (opts->ip6po_prefer_tempaddr ==
395 IP6PO_TEMPADDR_NOTPREFER) {
399 if (!(ia_best->ia6_flags & IN6_IFF_TEMPORARY) &&
400 (ia->ia6_flags & IN6_IFF_TEMPORARY)) {
406 if ((ia_best->ia6_flags & IN6_IFF_TEMPORARY) &&
407 !(ia->ia6_flags & IN6_IFF_TEMPORARY)) {
415 * Rule 8: prefer addresses on alive interfaces.
416 * This is a KAME specific rule.
418 if ((ia_best->ia_ifp->if_flags & IFF_UP) &&
419 !(ia->ia_ifp->if_flags & IFF_UP))
421 if (!(ia_best->ia_ifp->if_flags & IFF_UP) &&
422 (ia->ia_ifp->if_flags & IFF_UP))
426 * Rule 14: Use longest matching prefix.
427 * Note: in the address selection draft, this rule is
428 * documented as "Rule 8". However, since it is also
429 * documented that this rule can be overridden, we assign
430 * a large number so that it is easy to assign smaller numbers
431 * to more preferred rules.
433 new_matchlen = in6_matchlen(&ia->ia_addr.sin6_addr, &dst);
434 if (best_matchlen < new_matchlen)
436 if (new_matchlen < best_matchlen)
439 /* Rule 15 is reserved. */
442 * Last resort: just keep the current candidate.
443 * Or, do we need more rules?
449 best_scope = (new_scope >= 0 ? new_scope :
450 in6_addrscope(&ia_best->ia_addr.sin6_addr));
451 best_policy = (new_policy ? new_policy :
452 lookup_addrsel_policy(&ia_best->ia_addr));
453 best_matchlen = (new_matchlen >= 0 ? new_matchlen :
454 in6_matchlen(&ia_best->ia_addr.sin6_addr,
464 if ((ia = ia_best) == NULL) {
465 *errorp = EADDRNOTAVAIL;
472 return (&ia->ia_addr.sin6_addr);
476 * clone - meaningful only for bsdi and freebsd
479 selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
480 struct ip6_moptions *mopts, struct route_in6 *ro,
481 struct ifnet **retifp, struct rtentry **retrt, int norouteok)
483 INIT_VNET_INET6(curvnet);
485 struct ifnet *ifp = NULL;
486 struct rtentry *rt = NULL;
487 struct sockaddr_in6 *sin6_next;
488 struct in6_pktinfo *pi = NULL;
489 struct in6_addr *dst = &dstsock->sin6_addr;
491 char ip6buf[INET6_ADDRSTRLEN];
493 if (dstsock->sin6_addr.s6_addr32[0] == 0 &&
494 dstsock->sin6_addr.s6_addr32[1] == 0 &&
495 !IN6_IS_ADDR_LOOPBACK(&dstsock->sin6_addr)) {
496 printf("in6_selectroute: strange destination %s\n",
497 ip6_sprintf(ip6buf, &dstsock->sin6_addr));
499 printf("in6_selectroute: destination = %s%%%d\n",
500 ip6_sprintf(ip6buf, &dstsock->sin6_addr),
501 dstsock->sin6_scope_id); /* for debug */
505 /* If the caller specify the outgoing interface explicitly, use it. */
506 if (opts && (pi = opts->ip6po_pktinfo) != NULL && pi->ipi6_ifindex) {
507 /* XXX boundary check is assumed to be already done. */
508 ifp = ifnet_byindex(pi->ipi6_ifindex);
510 (norouteok || retrt == NULL ||
511 IN6_IS_ADDR_MULTICAST(dst))) {
513 * we do not have to check or get the route for
522 * If the destination address is a multicast address and the outgoing
523 * interface for the address is specified by the caller, use it.
525 if (IN6_IS_ADDR_MULTICAST(dst) &&
526 mopts != NULL && (ifp = mopts->im6o_multicast_ifp) != NULL) {
527 goto done; /* we do not need a route for multicast. */
532 * If the next hop address for the packet is specified by the caller,
533 * use it as the gateway.
535 if (opts && opts->ip6po_nexthop) {
536 struct route_in6 *ron;
539 sin6_next = satosin6(opts->ip6po_nexthop);
541 /* at this moment, we only support AF_INET6 next hops */
542 if (sin6_next->sin6_family != AF_INET6) {
543 error = EAFNOSUPPORT; /* or should we proceed? */
548 * If the next hop is an IPv6 address, then the node identified
549 * by that address must be a neighbor of the sending host.
551 ron = &opts->ip6po_nextroute;
553 * XXX what do we do here?
558 if (ron->ro_rt == NULL) {
559 rtalloc((struct route *)ron); /* multi path case? */
560 if (ron->ro_rt == NULL) {
565 error = EHOSTUNREACH;
573 la = lla_lookup(LLTABLE6(ifp), 0, (struct sockaddr *)&sin6_next->sin6_addr);
574 IF_AFDATA_UNLOCK(ifp);
578 error = EHOSTUNREACH;
583 (ron->ro_rt->rt_flags & (RTF_UP | RTF_LLINFO)) !=
584 (RTF_UP | RTF_LLINFO)) ||
585 !IN6_ARE_ADDR_EQUAL(&satosin6(&ron->ro_dst)->sin6_addr,
586 &sin6_next->sin6_addr)) {
591 *satosin6(&ron->ro_dst) = *sin6_next;
593 if (ron->ro_rt == NULL) {
594 rtalloc((struct route *)ron); /* multi path case? */
595 if (ron->ro_rt == NULL ||
596 !(ron->ro_rt->rt_flags & RTF_LLINFO)) {
601 error = EHOSTUNREACH;
608 * When cloning is required, try to allocate a route to the
609 * destination so that the caller can store path MTU
616 * Use a cached route if it exists and is valid, else try to allocate
617 * a new one. Note that we should check the address family of the
618 * cached destination, in case of sharing the cache with IPv4.
622 (!(ro->ro_rt->rt_flags & RTF_UP) ||
623 ((struct sockaddr *)(&ro->ro_dst))->sa_family != AF_INET6 ||
624 !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr,
627 ro->ro_rt = (struct rtentry *)NULL;
629 if (ro->ro_rt == (struct rtentry *)NULL) {
630 struct sockaddr_in6 *sa6;
632 /* No route yet, so try to acquire one */
633 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6));
634 sa6 = (struct sockaddr_in6 *)&ro->ro_dst;
636 sa6->sin6_scope_id = 0;
639 rtalloc_mpath((struct route *)ro,
640 ntohl(sa6->sin6_addr.s6_addr32[3]));
642 ro->ro_rt = rtalloc1(&((struct route *)ro)
645 RT_UNLOCK(ro->ro_rt);
650 * do not care about the result if we have the nexthop
651 * explicitly specified.
653 if (opts && opts->ip6po_nexthop)
657 ifp = ro->ro_rt->rt_ifp;
659 if (ifp == NULL) { /* can this really happen? */
664 if (ro->ro_rt == NULL)
665 error = EHOSTUNREACH;
669 * Check if the outgoing interface conflicts with
670 * the interface specified by ipi6_ifindex (if specified).
671 * Note that loopback interface is always okay.
672 * (this may happen when we are sending a packet to one of
673 * our own addresses.)
675 if (ifp && opts && opts->ip6po_pktinfo &&
676 opts->ip6po_pktinfo->ipi6_ifindex) {
677 if (!(ifp->if_flags & IFF_LOOPBACK) &&
679 opts->ip6po_pktinfo->ipi6_ifindex) {
680 error = EHOSTUNREACH;
687 if (ifp == NULL && rt == NULL) {
689 * This can happen if the caller did not pass a cached route
690 * nor any other hints. We treat this case an error.
692 error = EHOSTUNREACH;
694 if (error == EHOSTUNREACH)
695 V_ip6stat.ip6s_noroute++;
700 *retrt = rt; /* rt may be NULL */
706 in6_selectif(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
707 struct ip6_moptions *mopts, struct route_in6 *ro, struct ifnet **retifp)
710 struct route_in6 sro;
711 struct rtentry *rt = NULL;
714 bzero(&sro, sizeof(sro));
718 if ((error = selectroute(dstsock, opts, mopts, ro, retifp,
720 if (ro == &sro && rt && rt == sro.ro_rt)
726 * do not use a rejected or black hole route.
727 * XXX: this check should be done in the L2 output routine.
728 * However, if we skipped this check here, we'd see the following
730 * - install a rejected route for a scoped address prefix
732 * - send a packet to a destination that matches the scoped prefix,
733 * with ambiguity about the scope zone.
734 * - pick the outgoing interface from the route, and disambiguate the
735 * scope zone with the interface.
736 * - ip6_output() would try to get another route with the "new"
737 * destination, which may be valid.
738 * - we'd see no error on output.
739 * Although this may not be very harmful, it should still be confusing.
740 * We thus reject the case here.
742 if (rt && (rt->rt_flags & (RTF_REJECT | RTF_BLACKHOLE))) {
743 int flags = (rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
745 if (ro == &sro && rt && rt == sro.ro_rt)
751 * Adjust the "outgoing" interface. If we're going to loop the packet
752 * back to ourselves, the ifp would be the loopback interface.
753 * However, we'd rather know the interface associated to the
754 * destination address (which should probably be one of our own
757 if (rt && rt->rt_ifa && rt->rt_ifa->ifa_ifp)
758 *retifp = rt->rt_ifa->ifa_ifp;
760 if (ro == &sro && rt && rt == sro.ro_rt)
766 * clone - meaningful only for bsdi and freebsd
769 in6_selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
770 struct ip6_moptions *mopts, struct route_in6 *ro,
771 struct ifnet **retifp, struct rtentry **retrt)
774 return (selectroute(dstsock, opts, mopts, ro, retifp,
779 * Default hop limit selection. The precedence is as follows:
780 * 1. Hoplimit value specified via ioctl.
781 * 2. (If the outgoing interface is detected) the current
782 * hop limit of the interface specified by router advertisement.
783 * 3. The system default hoplimit.
786 in6_selecthlim(struct inpcb *in6p, struct ifnet *ifp)
788 INIT_VNET_INET6(curvnet);
790 if (in6p && in6p->in6p_hops >= 0)
791 return (in6p->in6p_hops);
793 return (ND_IFINFO(ifp)->chlim);
794 else if (in6p && !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
795 struct route_in6 ro6;
798 bzero(&ro6, sizeof(ro6));
799 ro6.ro_dst.sin6_family = AF_INET6;
800 ro6.ro_dst.sin6_len = sizeof(struct sockaddr_in6);
801 ro6.ro_dst.sin6_addr = in6p->in6p_faddr;
802 rtalloc((struct route *)&ro6);
804 lifp = ro6.ro_rt->rt_ifp;
807 return (ND_IFINFO(lifp)->chlim);
809 return (V_ip6_defhlim);
811 return (V_ip6_defhlim);
815 * XXX: this is borrowed from in6_pcbbind(). If possible, we should
816 * share this function by all *bsd*...
819 in6_pcbsetport(struct in6_addr *laddr, struct inpcb *inp, struct ucred *cred)
821 INIT_VNET_INET(curvnet);
822 struct socket *so = inp->inp_socket;
823 u_int16_t lport = 0, first, last, *lastport;
824 int count, error, wild = 0, dorandom;
825 struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
827 INP_INFO_WLOCK_ASSERT(pcbinfo);
828 INP_WLOCK_ASSERT(inp);
830 error = prison_local_ip6(cred, laddr,
831 ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0));
835 /* XXX: this is redundant when called from in6_pcbbind */
836 if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0)
837 wild = INPLOOKUP_WILDCARD;
839 inp->inp_flags |= INP_ANONPORT;
841 if (inp->inp_flags & INP_HIGHPORT) {
842 first = V_ipport_hifirstauto; /* sysctl */
843 last = V_ipport_hilastauto;
844 lastport = &pcbinfo->ipi_lasthi;
845 } else if (inp->inp_flags & INP_LOWPORT) {
846 error = priv_check_cred(cred, PRIV_NETINET_RESERVEDPORT, 0);
849 first = V_ipport_lowfirstauto; /* 1023 */
850 last = V_ipport_lowlastauto; /* 600 */
851 lastport = &pcbinfo->ipi_lastlow;
853 first = V_ipport_firstauto; /* sysctl */
854 last = V_ipport_lastauto;
855 lastport = &pcbinfo->ipi_lastport;
859 * For UDP, use random port allocation as long as the user
860 * allows it. For TCP (and as of yet unknown) connections,
861 * use random port allocation only if the user allows it AND
862 * ipport_tick() allows it.
864 if (V_ipport_randomized &&
865 (!V_ipport_stoprandom || pcbinfo == &V_udbinfo))
870 * It makes no sense to do random port allocation if
871 * we have the only port available.
875 /* Make sure to not include UDP packets in the count. */
876 if (pcbinfo != &V_udbinfo)
877 V_ipport_tcpallocs++;
880 * Instead of having two loops further down counting up or down
881 * make sure that first is always <= last and go with only one
882 * code path implementing all logic.
893 *lastport = first + (arc4random() % (last - first));
895 count = last - first;
898 if (count-- < 0) { /* completely used? */
899 /* Undo an address bind that may have occurred. */
900 inp->in6p_laddr = in6addr_any;
901 return (EADDRNOTAVAIL);
904 if (*lastport < first || *lastport > last)
906 lport = htons(*lastport);
907 } while (in6_pcblookup_local(pcbinfo, &inp->in6p_laddr,
910 inp->inp_lport = lport;
911 if (in_pcbinshash(inp) != 0) {
912 inp->in6p_laddr = in6addr_any;
921 addrsel_policy_init(void)
923 INIT_VNET_INET6(curvnet);
925 V_ip6_prefer_tempaddr = 0;
929 /* initialize the "last resort" policy */
930 bzero(&V_defaultaddrpolicy, sizeof(V_defaultaddrpolicy));
931 V_defaultaddrpolicy.label = ADDR_LABEL_NOTAPP;
933 if (!IS_DEFAULT_VNET(curvnet))
937 ADDRSEL_SXLOCK_INIT();
940 static struct in6_addrpolicy *
941 lookup_addrsel_policy(struct sockaddr_in6 *key)
943 INIT_VNET_INET6(curvnet);
944 struct in6_addrpolicy *match = NULL;
947 match = match_addrsel_policy(key);
950 match = &V_defaultaddrpolicy;
959 * Subroutines to manage the address selection policy table via sysctl.
962 struct sysctl_req *w_req;
965 static int in6_src_sysctl(SYSCTL_HANDLER_ARGS);
966 SYSCTL_DECL(_net_inet6_ip6);
967 SYSCTL_NODE(_net_inet6_ip6, IPV6CTL_ADDRCTLPOLICY, addrctlpolicy,
968 CTLFLAG_RD, in6_src_sysctl, "");
971 in6_src_sysctl(SYSCTL_HANDLER_ARGS)
978 bzero(&w, sizeof(w));
981 return (walk_addrsel_policy(dump_addrsel_policyent, &w));
985 in6_src_ioctl(u_long cmd, caddr_t data)
988 struct in6_addrpolicy ent0;
990 if (cmd != SIOCAADDRCTL_POLICY && cmd != SIOCDADDRCTL_POLICY)
991 return (EOPNOTSUPP); /* check for safety */
993 ent0 = *(struct in6_addrpolicy *)data;
995 if (ent0.label == ADDR_LABEL_NOTAPP)
997 /* check if the prefix mask is consecutive. */
998 if (in6_mask2len(&ent0.addrmask.sin6_addr, NULL) < 0)
1000 /* clear trailing garbages (if any) of the prefix address. */
1001 for (i = 0; i < 4; i++) {
1002 ent0.addr.sin6_addr.s6_addr32[i] &=
1003 ent0.addrmask.sin6_addr.s6_addr32[i];
1008 case SIOCAADDRCTL_POLICY:
1009 return (add_addrsel_policyent(&ent0));
1010 case SIOCDADDRCTL_POLICY:
1011 return (delete_addrsel_policyent(&ent0));
1014 return (0); /* XXX: compromise compilers */
1018 * The followings are implementation of the policy table using a
1019 * simple tail queue.
1020 * XXX such details should be hidden.
1021 * XXX implementation using binary tree should be more efficient.
1023 struct addrsel_policyent {
1024 TAILQ_ENTRY(addrsel_policyent) ape_entry;
1025 struct in6_addrpolicy ape_policy;
1028 TAILQ_HEAD(addrsel_policyhead, addrsel_policyent);
1030 #ifdef VIMAGE_GLOBALS
1031 struct addrsel_policyhead addrsel_policytab;
1035 init_policy_queue(void)
1037 INIT_VNET_INET6(curvnet);
1039 TAILQ_INIT(&V_addrsel_policytab);
1043 add_addrsel_policyent(struct in6_addrpolicy *newpolicy)
1045 INIT_VNET_INET6(curvnet);
1046 struct addrsel_policyent *new, *pol;
1048 new = malloc(sizeof(*new), M_IFADDR,
1053 /* duplication check */
1054 TAILQ_FOREACH(pol, &V_addrsel_policytab, ape_entry) {
1055 if (IN6_ARE_ADDR_EQUAL(&newpolicy->addr.sin6_addr,
1056 &pol->ape_policy.addr.sin6_addr) &&
1057 IN6_ARE_ADDR_EQUAL(&newpolicy->addrmask.sin6_addr,
1058 &pol->ape_policy.addrmask.sin6_addr)) {
1061 free(new, M_IFADDR);
1062 return (EEXIST); /* or override it? */
1066 bzero(new, sizeof(*new));
1068 /* XXX: should validate entry */
1069 new->ape_policy = *newpolicy;
1071 TAILQ_INSERT_TAIL(&V_addrsel_policytab, new, ape_entry);
1079 delete_addrsel_policyent(struct in6_addrpolicy *key)
1081 INIT_VNET_INET6(curvnet);
1082 struct addrsel_policyent *pol;
1087 /* search for the entry in the table */
1088 TAILQ_FOREACH(pol, &V_addrsel_policytab, ape_entry) {
1089 if (IN6_ARE_ADDR_EQUAL(&key->addr.sin6_addr,
1090 &pol->ape_policy.addr.sin6_addr) &&
1091 IN6_ARE_ADDR_EQUAL(&key->addrmask.sin6_addr,
1092 &pol->ape_policy.addrmask.sin6_addr)) {
1102 TAILQ_REMOVE(&V_addrsel_policytab, pol, ape_entry);
1110 walk_addrsel_policy(int (*callback)(struct in6_addrpolicy *, void *),
1113 INIT_VNET_INET6(curvnet);
1114 struct addrsel_policyent *pol;
1118 TAILQ_FOREACH(pol, &V_addrsel_policytab, ape_entry) {
1119 if ((error = (*callback)(&pol->ape_policy, w)) != 0) {
1129 dump_addrsel_policyent(struct in6_addrpolicy *pol, void *arg)
1132 struct walkarg *w = arg;
1134 error = SYSCTL_OUT(w->w_req, pol, sizeof(*pol));
1139 static struct in6_addrpolicy *
1140 match_addrsel_policy(struct sockaddr_in6 *key)
1142 INIT_VNET_INET6(curvnet);
1143 struct addrsel_policyent *pent;
1144 struct in6_addrpolicy *bestpol = NULL, *pol;
1145 int matchlen, bestmatchlen = -1;
1146 u_char *mp, *ep, *k, *p, m;
1148 TAILQ_FOREACH(pent, &V_addrsel_policytab, ape_entry) {
1151 pol = &pent->ape_policy;
1152 mp = (u_char *)&pol->addrmask.sin6_addr;
1153 ep = mp + 16; /* XXX: scope field? */
1154 k = (u_char *)&key->sin6_addr;
1155 p = (u_char *)&pol->addr.sin6_addr;
1156 for (; mp < ep && *mp; mp++, k++, p++) {
1159 goto next; /* not match */
1160 if (m == 0xff) /* short cut for a typical case */
1170 /* matched. check if this is better than the current best. */
1171 if (bestpol == NULL ||
1172 matchlen > bestmatchlen) {
1174 bestmatchlen = matchlen;