/* * Copyright (c) 2000-2012 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* $FreeBSD: src/sys/netinet6/in6_src.c,v 1.1.2.2 2001/07/03 11:01:52 ume Exp $ */ /* $KAME: in6_src.c,v 1.37 2001/03/29 05:34:31 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Copyright (c) 1982, 1986, 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)in_pcb.c 8.2 (Berkeley) 1/4/94 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "loop.h" SYSCTL_DECL(_net_inet6_ip6); static int ip6_select_srcif_debug = 0; SYSCTL_INT(_net_inet6_ip6, OID_AUTO, select_srcif_debug, CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_select_srcif_debug, 0, "log source interface selection debug info"); #define ADDR_LABEL_NOTAPP (-1) struct in6_addrpolicy defaultaddrpolicy; int ip6_prefer_tempaddr = 1; #ifdef ENABLE_ADDRSEL extern lck_mtx_t *addrsel_mutex; #define ADDRSEL_LOCK() lck_mtx_lock(addrsel_mutex) #define ADDRSEL_UNLOCK() lck_mtx_unlock(addrsel_mutex) #else #define ADDRSEL_LOCK() #define ADDRSEL_UNLOCK() #endif static int selectroute(struct sockaddr_in6 *, struct sockaddr_in6 *, struct ip6_pktopts *, struct ip6_moptions *, struct route_in6 *, struct ifnet **, struct rtentry **, int, int, const struct ip6_out_args *ip6oa); static int in6_selectif(struct sockaddr_in6 *, struct ip6_pktopts *, struct ip6_moptions *, struct route_in6 *ro, const struct ip6_out_args *, struct ifnet **); static void init_policy_queue(void); static int add_addrsel_policyent(const struct in6_addrpolicy *); #ifdef ENABLE_ADDRSEL static int delete_addrsel_policyent(const struct in6_addrpolicy *); #endif static int walk_addrsel_policy(int (*)(const struct in6_addrpolicy *, void *), void *); static int dump_addrsel_policyent(const struct in6_addrpolicy *, void *); static struct in6_addrpolicy *match_addrsel_policy(struct sockaddr_in6 *); void addrsel_policy_init(void); /* * Return an IPv6 address, which is the most appropriate for a given * destination and user specified options. * If necessary, this function lookups the routing table and returns * an entry to the caller for later use. */ #define REPLACE(r) do {\ if ((r) < sizeof(ip6stat.ip6s_sources_rule) / \ sizeof(ip6stat.ip6s_sources_rule[0])) /* check for safety */ \ ip6stat.ip6s_sources_rule[(r)]++; \ goto replace; \ } while(0) #define NEXTSRC(r) do {\ if ((r) < sizeof(ip6stat.ip6s_sources_rule) / \ sizeof(ip6stat.ip6s_sources_rule[0])) /* check for safety */ \ ip6stat.ip6s_sources_rule[(r)]++; \ goto next; /* XXX: we can't use 'continue' here */ \ } while(0) #define BREAK(r) do { \ if ((r) < sizeof(ip6stat.ip6s_sources_rule) / \ sizeof(ip6stat.ip6s_sources_rule[0])) /* check for safety */ \ ip6stat.ip6s_sources_rule[(r)]++; \ goto out; /* XXX: we can't use 'break' here */ \ } while(0) /* * Regardless of error, it will return an ifp with a reference held if the * caller provides a non-NULL ifpp. The caller is responsible for checking * if the returned ifp is valid and release its reference at all times. */ struct in6_addr * in6_selectsrc(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, struct inpcb *inp, struct route_in6 *ro, struct ifnet **ifpp, struct in6_addr *src_storage, unsigned int ifscope, int *errorp) { struct in6_addr dst; struct ifnet *ifp = NULL; struct in6_ifaddr *ia = NULL, *ia_best = NULL; struct in6_pktinfo *pi = NULL; int dst_scope = -1, best_scope = -1, best_matchlen = -1; struct in6_addrpolicy *dst_policy = NULL, *best_policy = NULL; u_int32_t odstzone; int prefer_tempaddr; struct ip6_moptions *mopts; struct timeval timenow; struct ip6_out_args ip6oa = { ifscope, { 0 }, IP6OAF_SELECT_SRCIF }; boolean_t islocal = FALSE; getmicrotime(&timenow); dst = dstsock->sin6_addr; /* make a copy for local operation */ *errorp = 0; if (ifpp != NULL) *ifpp = NULL; if (inp != NULL) { mopts = inp->in6p_moptions; if (inp->inp_flags & INP_NO_IFT_CELLULAR) ip6oa.ip6oa_flags |= IP6OAF_NO_CELLULAR; } else { mopts = NULL; } if (ip6oa.ip6oa_boundif != IFSCOPE_NONE) ip6oa.ip6oa_flags |= IP6OAF_BOUND_IF; /* * If the source address is explicitly specified by the caller, * check if the requested source address is indeed a unicast address * assigned to the node, and can be used as the packet's source * address. If everything is okay, use the address as source. */ if (opts && (pi = opts->ip6po_pktinfo) && !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) { struct sockaddr_in6 srcsock; struct in6_ifaddr *ia6; /* get the outgoing interface */ if ((*errorp = in6_selectif(dstsock, opts, mopts, ro, &ip6oa, &ifp)) != 0) { src_storage = NULL; goto done; } /* * determine the appropriate zone id of the source based on * the zone of the destination and the outgoing interface. * If the specified address is ambiguous wrt the scope zone, * the interface must be specified; otherwise, ifa_ifwithaddr() * will fail matching the address. */ bzero(&srcsock, sizeof(srcsock)); srcsock.sin6_family = AF_INET6; srcsock.sin6_len = sizeof(srcsock); srcsock.sin6_addr = pi->ipi6_addr; if (ifp != NULL) { *errorp = in6_setscope(&srcsock.sin6_addr, ifp, NULL); if (*errorp != 0) { src_storage = NULL; goto done; } } ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *) (&srcsock)); if (ia6 == NULL) { *errorp = EADDRNOTAVAIL; src_storage = NULL; goto done; } IFA_LOCK_SPIN(&ia6->ia_ifa); if ((ia6->ia6_flags & (IN6_IFF_ANYCAST | IN6_IFF_NOTREADY)) || ((ip6oa.ip6oa_flags & IP6OAF_NO_CELLULAR) && (ia6->ia_ifa.ifa_ifp->if_type == IFT_CELLULAR))) { IFA_UNLOCK(&ia6->ia_ifa); IFA_REMREF(&ia6->ia_ifa); *errorp = EADDRNOTAVAIL; src_storage = NULL; goto done; } *src_storage = satosin6(&ia6->ia_addr)->sin6_addr; IFA_UNLOCK(&ia6->ia_ifa); IFA_REMREF(&ia6->ia_ifa); goto done; } /* * Otherwise, if the socket has already bound the source, just use it. */ if (inp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) { src_storage = &inp->in6p_laddr; goto done; } /* * If the address is not specified, choose the best one based on * the outgoing interface and the destination address. */ /* get the outgoing interface */ if ((*errorp = in6_selectif(dstsock, opts, mopts, ro, &ip6oa, &ifp)) != 0) { src_storage = NULL; goto done; } *errorp = in6_setscope(&dst, ifp, &odstzone); if (*errorp != 0) { src_storage = NULL; goto done; } lck_rw_lock_shared(&in6_ifaddr_rwlock); for (ia = in6_ifaddrs; ia; ia = ia->ia_next) { int new_scope = -1, new_matchlen = -1; struct in6_addrpolicy *new_policy = NULL; u_int32_t srczone, osrczone, dstzone; struct in6_addr src; struct ifnet *ifp1 = ia->ia_ifp; IFA_LOCK(&ia->ia_ifa); /* * We'll never take an address that breaks the scope zone * of the destination. We also skip an address if its zone * does not contain the outgoing interface. * XXX: we should probably use sin6_scope_id here. */ if (in6_setscope(&dst, ifp1, &dstzone) || odstzone != dstzone) goto next; src = ia->ia_addr.sin6_addr; if (in6_setscope(&src, ifp, &osrczone) || in6_setscope(&src, ifp1, &srczone) || osrczone != srczone) goto next; /* avoid unusable addresses */ if ((ia->ia6_flags & (IN6_IFF_NOTREADY | IN6_IFF_ANYCAST | IN6_IFF_DETACHED))) goto next; if (!ip6_use_deprecated && IFA6_IS_DEPRECATED(ia)) goto next; if (!nd6_optimistic_dad && (ia->ia6_flags & IN6_IFF_OPTIMISTIC) != 0) goto next; /* Rule 1: Prefer same address */ if (IN6_ARE_ADDR_EQUAL(&dst, &ia->ia_addr.sin6_addr)) BREAK(1); /* there should be no better candidate */ if (ia_best == NULL) REPLACE(0); /* Rule 2: Prefer appropriate scope */ if (dst_scope < 0) dst_scope = in6_addrscope(&dst); new_scope = in6_addrscope(&ia->ia_addr.sin6_addr); if (IN6_ARE_SCOPE_CMP(best_scope, new_scope) < 0) { if (IN6_ARE_SCOPE_CMP(best_scope, dst_scope) < 0) REPLACE(2); NEXTSRC(2); } else if (IN6_ARE_SCOPE_CMP(new_scope, best_scope) < 0) { if (IN6_ARE_SCOPE_CMP(new_scope, dst_scope) < 0) NEXTSRC(2); REPLACE(2); } /* * Rule 3: Avoid deprecated addresses. Note that the case of * !ip6_use_deprecated is already rejected above. */ if (!IFA6_IS_DEPRECATED(ia_best) && IFA6_IS_DEPRECATED(ia)) NEXTSRC(3); if (IFA6_IS_DEPRECATED(ia_best) && !IFA6_IS_DEPRECATED(ia)) REPLACE(3); /* * RFC 4429 says that optimistic addresses are equivalent to * deprecated addresses, so avoid them here. */ if ((ia_best->ia6_flags & IN6_IFF_OPTIMISTIC) == 0 && (ia->ia6_flags & IN6_IFF_OPTIMISTIC) != 0) NEXTSRC(3); if ((ia_best->ia6_flags & IN6_IFF_OPTIMISTIC) != 0 && (ia->ia6_flags & IN6_IFF_OPTIMISTIC) == 0) REPLACE(3); /* Rule 4: Prefer home addresses */ /* * XXX: This is a TODO. We should probably merge the MIP6 * case above. */ /* Rule 5: Prefer outgoing interface */ if (ia_best->ia_ifp == ifp && ia->ia_ifp != ifp) NEXTSRC(5); if (ia_best->ia_ifp != ifp && ia->ia_ifp == ifp) REPLACE(5); /* * Rule 6: Prefer matching label * Note that best_policy should be non-NULL here. */ if (dst_policy == NULL) dst_policy = in6_addrsel_lookup_policy(dstsock); if (dst_policy->label != ADDR_LABEL_NOTAPP) { new_policy = in6_addrsel_lookup_policy(&ia->ia_addr); if (dst_policy->label == best_policy->label && dst_policy->label != new_policy->label) NEXTSRC(6); if (dst_policy->label != best_policy->label && dst_policy->label == new_policy->label) REPLACE(6); } /* * Rule 7: Prefer public addresses. * We allow users to reverse the logic by configuring * a sysctl variable, so that privacy conscious users can * always prefer temporary addresses. * Don't use temporary addresses for local destinations or * for multicast addresses unless we were passed in an option. */ if (IN6_IS_ADDR_MULTICAST(&dst) || in6_matchlen(&ia_best->ia_addr.sin6_addr, &dst) >= in6_mask2len(&ia_best->ia_prefixmask.sin6_addr, NULL)) islocal = TRUE; if (opts == NULL || opts->ip6po_prefer_tempaddr == IP6PO_TEMPADDR_SYSTEM) { prefer_tempaddr = islocal ? 0 : ip6_prefer_tempaddr; } else if (opts->ip6po_prefer_tempaddr == IP6PO_TEMPADDR_NOTPREFER) { prefer_tempaddr = 0; } else prefer_tempaddr = 1; if (!(ia_best->ia6_flags & IN6_IFF_TEMPORARY) && (ia->ia6_flags & IN6_IFF_TEMPORARY)) { if (prefer_tempaddr) REPLACE(7); else NEXTSRC(7); } if ((ia_best->ia6_flags & IN6_IFF_TEMPORARY) && !(ia->ia6_flags & IN6_IFF_TEMPORARY)) { if (prefer_tempaddr) NEXTSRC(7); else REPLACE(7); } /* * Rule 8: prefer addresses on alive interfaces. * This is a KAME specific rule. */ if ((ia_best->ia_ifp->if_flags & IFF_UP) && !(ia->ia_ifp->if_flags & IFF_UP)) NEXTSRC(8); if (!(ia_best->ia_ifp->if_flags & IFF_UP) && (ia->ia_ifp->if_flags & IFF_UP)) REPLACE(8); /* * Rule 14: Use longest matching prefix. * Note: in the address selection draft, this rule is * documented as "Rule 8". However, since it is also * documented that this rule can be overridden, we assign * a large number so that it is easy to assign smaller numbers * to more preferred rules. */ new_matchlen = in6_matchlen(&ia->ia_addr.sin6_addr, &dst); if (best_matchlen < new_matchlen) REPLACE(14); if (new_matchlen < best_matchlen) NEXTSRC(14); /* Rule 15 is reserved. */ /* * Last resort: just keep the current candidate. * Or, do we need more rules? */ IFA_UNLOCK(&ia->ia_ifa); continue; replace: best_scope = (new_scope >= 0 ? new_scope : in6_addrscope(&ia->ia_addr.sin6_addr)); best_policy = (new_policy ? new_policy : in6_addrsel_lookup_policy(&ia->ia_addr)); best_matchlen = (new_matchlen >= 0 ? new_matchlen : in6_matchlen(&ia->ia_addr.sin6_addr, &dst)); IFA_ADDREF_LOCKED(&ia->ia_ifa); /* for ia_best */ IFA_UNLOCK(&ia->ia_ifa); if (ia_best != NULL) IFA_REMREF(&ia_best->ia_ifa); ia_best = ia; continue; next: IFA_UNLOCK(&ia->ia_ifa); continue; out: IFA_ADDREF_LOCKED(&ia->ia_ifa); /* for ia_best */ IFA_UNLOCK(&ia->ia_ifa); if (ia_best != NULL) IFA_REMREF(&ia_best->ia_ifa); ia_best = ia; break; } lck_rw_done(&in6_ifaddr_rwlock); if (ia_best != NULL && (ip6oa.ip6oa_flags & IP6OAF_NO_CELLULAR) && ia_best->ia_ifa.ifa_ifp->if_type == IFT_CELLULAR) { IFA_REMREF(&ia_best->ia_ifa); ia_best = NULL; } if ((ia = ia_best) == NULL) { *errorp = EADDRNOTAVAIL; src_storage = NULL; goto done; } IFA_LOCK_SPIN(&ia->ia_ifa); *src_storage = satosin6(&ia->ia_addr)->sin6_addr; IFA_UNLOCK(&ia->ia_ifa); IFA_REMREF(&ia->ia_ifa); done: if (ifpp != NULL) { /* if ifp is non-NULL, refcnt held in in6_selectif() */ *ifpp = ifp; } else if (ifp != NULL) { ifnet_release(ifp); } return (src_storage); } /* * Given a source IPv6 address (and route, if available), determine the best * interface to send the packet from. Checking for (and updating) the * ROF_SRCIF_SELECTED flag in the pcb-supplied route placeholder is done * without any locks, based on the assumption that in the event this is * called from ip6_output(), the output operation is single-threaded per-pcb, * i.e. for any given pcb there can only be one thread performing output at * the IPv6 layer. * * This routine is analogous to in_selectsrcif() for IPv4. Regardless of * error, it will return an ifp with a reference held if the caller provides * a non-NULL retifp. The caller is responsible for checking if the * returned ifp is valid and release its reference at all times. * * clone - meaningful only for bsdi and freebsd */ static int selectroute(struct sockaddr_in6 *srcsock, struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, struct ip6_moptions *mopts, struct route_in6 *ro, struct ifnet **retifp, struct rtentry **retrt, int clone, int norouteok, const struct ip6_out_args *ip6oa) { int error = 0; struct ifnet *ifp = NULL, *ifp0 = NULL; struct route_in6 *route = NULL; struct sockaddr_in6 *sin6_next; struct in6_pktinfo *pi = NULL; struct in6_addr *dst = &dstsock->sin6_addr; struct ifaddr *ifa = NULL; char s_src[MAX_IPv6_STR_LEN], s_dst[MAX_IPv6_STR_LEN]; boolean_t select_srcif, proxied_ifa = FALSE; unsigned int ifscope = ip6oa->ip6oa_boundif; #if 0 char ip6buf[INET6_ADDRSTRLEN]; if (dstsock->sin6_addr.s6_addr32[0] == 0 && dstsock->sin6_addr.s6_addr32[1] == 0 && !IN6_IS_ADDR_LOOPBACK(&dstsock->sin6_addr)) { printf("in6_selectroute: strange destination %s\n", ip6_sprintf(ip6buf, &dstsock->sin6_addr)); } else { printf("in6_selectroute: destination = %s%%%d\n", ip6_sprintf(ip6buf, &dstsock->sin6_addr), dstsock->sin6_scope_id); /* for debug */ } #endif if (retifp != NULL) *retifp = NULL; if (retrt != NULL) *retrt = NULL; if (ip6_select_srcif_debug) { struct in6_addr src; src = (srcsock != NULL) ? srcsock->sin6_addr : in6addr_any; (void) inet_ntop(AF_INET6, &src, s_src, sizeof (s_src)); (void) inet_ntop(AF_INET6, dst, s_dst, sizeof (s_dst)); } /* * If the destination address is UNSPECIFIED addr, bail out. */ if (IN6_IS_ADDR_UNSPECIFIED(dst)) { error = EHOSTUNREACH; goto done; } /* * Perform source interface selection only if Scoped Routing * is enabled and a source address that isn't unspecified. */ select_srcif = (ip6_doscopedroute && srcsock != NULL && !IN6_IS_ADDR_UNSPECIFIED(&srcsock->sin6_addr)); /* * If Scoped Routing is disabled, ignore the given ifscope. * Otherwise even if source selection won't be performed, * we still obey IPV6_BOUND_IF. */ if (!ip6_doscopedroute && ifscope != IFSCOPE_NONE) ifscope = IFSCOPE_NONE; /* If the caller specified the outgoing interface explicitly, use it */ if (opts != NULL && (pi = opts->ip6po_pktinfo) != NULL && pi->ipi6_ifindex != 0) { /* * If IPV6_PKTINFO takes precedence over IPV6_BOUND_IF. */ ifscope = pi->ipi6_ifindex; ifnet_head_lock_shared(); /* ifp may be NULL if detached or out of range */ ifp = ifp0 = ((ifscope <= if_index) ? ifindex2ifnet[ifscope] : NULL); ifnet_head_done(); if (norouteok || retrt == NULL || IN6_IS_ADDR_MULTICAST(dst)) { /* * We do not have to check or get the route for * multicast. If the caller didn't ask/care for * the route and we have no interface to use, * it's an error. */ if (ifp == NULL) error = EHOSTUNREACH; goto done; } else { goto getsrcif; } } /* * If the destination address is a multicast address and the outgoing * interface for the address is specified by the caller, use it. */ if (IN6_IS_ADDR_MULTICAST(dst) && mopts != NULL) { IM6O_LOCK(mopts); if ((ifp = ifp0 = mopts->im6o_multicast_ifp) != NULL) { IM6O_UNLOCK(mopts); goto done; /* we do not need a route for multicast. */ } IM6O_UNLOCK(mopts); } getsrcif: /* * If the outgoing interface was not set via IPV6_BOUND_IF or * IPV6_PKTINFO, use the scope ID in the destination address. */ if (ip6_doscopedroute && ifscope == IFSCOPE_NONE) ifscope = dstsock->sin6_scope_id; /* * Perform source interface selection; the source IPv6 address * must belong to one of the addresses of the interface used * by the route. For performance reasons, do this only if * there is no route, or if the routing table has changed, * or if we haven't done source interface selection on this * route (for this PCB instance) before. */ if (!select_srcif || (ro != NULL && ro->ro_rt != NULL && (ro->ro_rt->rt_flags & RTF_UP) && ro->ro_rt->generation_id == route_generation && (ro->ro_flags & ROF_SRCIF_SELECTED))) { if (ro != NULL && ro->ro_rt != NULL) { ifa = ro->ro_rt->rt_ifa; IFA_ADDREF(ifa); } goto getroute; } /* * Given the source IPv6 address, find a suitable source interface * to use for transmission; if a scope ID has been specified, * optimize the search by looking at the addresses only for that * interface. This is still suboptimal, however, as we need to * traverse the per-interface list. */ if (ifscope != IFSCOPE_NONE || (ro != NULL && ro->ro_rt != NULL)) { unsigned int scope = ifscope; struct ifnet *rt_ifp; rt_ifp = (ro->ro_rt != NULL) ? ro->ro_rt->rt_ifp : NULL; /* * If no scope is specified and the route is stale (pointing * to a defunct interface) use the current primary interface; * this happens when switching between interfaces configured * with the same IPv6 address. Otherwise pick up the scope * information from the route; the ULP may have looked up a * correct route and we just need to verify it here and mark * it with the ROF_SRCIF_SELECTED flag below. */ if (scope == IFSCOPE_NONE) { scope = rt_ifp->if_index; if (scope != get_primary_ifscope(AF_INET6) && ro->ro_rt->generation_id != route_generation) scope = get_primary_ifscope(AF_INET6); } ifa = (struct ifaddr *) ifa_foraddr6_scoped(&srcsock->sin6_addr, scope); /* * If we are forwarding and proxying prefix(es), see if the * source address is one of ours and is a proxied address; * if so, use it. */ if (ifa == NULL && ip6_forwarding && nd6_prproxy) { ifa = (struct ifaddr *) ifa_foraddr6(&srcsock->sin6_addr); if (ifa != NULL && !(proxied_ifa = nd6_prproxy_ifaddr((struct in6_ifaddr *)ifa))) { IFA_REMREF(ifa); ifa = NULL; } } if (ip6_select_srcif_debug && ifa != NULL) { if (ro->ro_rt != NULL) { printf("%s->%s ifscope %d->%d ifa_if %s " "ro_if %s\n", s_src, s_dst, ifscope, scope, if_name(ifa->ifa_ifp), if_name(rt_ifp)); } else { printf("%s->%s ifscope %d->%d ifa_if %s\n", s_src, s_dst, ifscope, scope, if_name(ifa->ifa_ifp)); } } } /* * Slow path; search for an interface having the corresponding source * IPv6 address if the scope was not specified by the caller, and: * * 1) There currently isn't any route, or, * 2) The interface used by the route does not own that source * IPv6 address; in this case, the route will get blown away * and we'll do a more specific scoped search using the newly * found interface. */ if (ifa == NULL && ifscope == IFSCOPE_NONE) { ifa = (struct ifaddr *)ifa_foraddr6(&srcsock->sin6_addr); if (ip6_select_srcif_debug && ifa != NULL) { printf("%s->%s ifscope %d ifa_if %s\n", s_src, s_dst, ifscope, if_name(ifa->ifa_ifp)); } } getroute: if (ifa != NULL && !proxied_ifa) ifscope = ifa->ifa_ifp->if_index; /* * If the next hop address for the packet is specified by the caller, * use it as the gateway. */ if (opts != NULL && opts->ip6po_nexthop != NULL) { struct route_in6 *ron; sin6_next = satosin6(opts->ip6po_nexthop); /* at this moment, we only support AF_INET6 next hops */ if (sin6_next->sin6_family != AF_INET6) { error = EAFNOSUPPORT; /* or should we proceed? */ goto done; } /* * If the next hop is an IPv6 address, then the node identified * by that address must be a neighbor of the sending host. */ ron = &opts->ip6po_nextroute; if (ron->ro_rt != NULL) RT_LOCK(ron->ro_rt); if ((ron->ro_rt != NULL && ((ron->ro_rt->rt_flags & (RTF_UP | RTF_LLINFO)) != (RTF_UP | RTF_LLINFO) || ron->ro_rt->generation_id != route_generation || (select_srcif && (ifa == NULL || (ifa->ifa_ifp != ron->ro_rt->rt_ifp && !proxied_ifa))))) || !IN6_ARE_ADDR_EQUAL(&satosin6(&ron->ro_dst)->sin6_addr, &sin6_next->sin6_addr)) { if (ron->ro_rt != NULL) { RT_UNLOCK(ron->ro_rt); rtfree(ron->ro_rt); ron->ro_rt = NULL; } *satosin6(&ron->ro_dst) = *sin6_next; } if (ron->ro_rt == NULL) { rtalloc_scoped((struct route *)ron, ifscope); if (ron->ro_rt != NULL) RT_LOCK(ron->ro_rt); if (ron->ro_rt == NULL || !(ron->ro_rt->rt_flags & RTF_LLINFO) || !IN6_ARE_ADDR_EQUAL(&satosin6(rt_key(ron->ro_rt))-> sin6_addr, &sin6_next->sin6_addr)) { if (ron->ro_rt != NULL) { RT_UNLOCK(ron->ro_rt); rtfree(ron->ro_rt); ron->ro_rt = NULL; } error = EHOSTUNREACH; goto done; } } route = ron; ifp = ifp0 = ron->ro_rt->rt_ifp; /* * When cloning is required, try to allocate a route to the * destination so that the caller can store path MTU * information. */ if (!clone) { if (select_srcif) { /* Keep the route locked */ goto validateroute; } RT_UNLOCK(ron->ro_rt); goto done; } RT_UNLOCK(ron->ro_rt); } /* * Use a cached route if it exists and is valid, else try to allocate * a new one. Note that we should check the address family of the * cached destination, in case of sharing the cache with IPv4. */ if (ro == NULL) goto done; if (ro->ro_rt != NULL) RT_LOCK(ro->ro_rt); if (ro->ro_rt != NULL && (!(ro->ro_rt->rt_flags & RTF_UP) || satosin6(&ro->ro_dst)->sin6_family != AF_INET6 || ro->ro_rt->generation_id != route_generation || !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, dst) || (select_srcif && (ifa == NULL || (ifa->ifa_ifp != ro->ro_rt->rt_ifp && !proxied_ifa))))) { RT_UNLOCK(ro->ro_rt); rtfree(ro->ro_rt); ro->ro_rt = NULL; } if (ro->ro_rt == NULL) { struct sockaddr_in6 *sa6; if (ro->ro_rt != NULL) RT_UNLOCK(ro->ro_rt); /* No route yet, so try to acquire one */ bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); sa6 = (struct sockaddr_in6 *)&ro->ro_dst; sa6->sin6_family = AF_INET6; sa6->sin6_len = sizeof(struct sockaddr_in6); sa6->sin6_addr = *dst; if (IN6_IS_ADDR_MULTICAST(dst)) { ro->ro_rt = rtalloc1_scoped( &((struct route *)ro)->ro_dst, 0, 0, ifscope); } else { rtalloc_scoped((struct route *)ro, ifscope); } if (ro->ro_rt != NULL) RT_LOCK(ro->ro_rt); } /* * Do not care about the result if we have the nexthop * explicitly specified (in case we're asked to clone.) */ if (opts != NULL && opts->ip6po_nexthop != NULL) { if (ro->ro_rt != NULL) RT_UNLOCK(ro->ro_rt); goto done; } if (ro->ro_rt != NULL) { RT_LOCK_ASSERT_HELD(ro->ro_rt); ifp = ifp0 = ro->ro_rt->rt_ifp; } else { error = EHOSTUNREACH; } route = ro; validateroute: if (select_srcif) { boolean_t has_route = (route != NULL && route->ro_rt != NULL); boolean_t srcif_selected = FALSE; if (has_route) RT_LOCK_ASSERT_HELD(route->ro_rt); /* * If there is a non-loopback route with the wrong interface, * or if there is no interface configured with such an address, * blow it away. Except for local/loopback, we look for one * with a matching interface scope/index. */ if (has_route && (ifa == NULL || (ifa->ifa_ifp != ifp && ifp != lo_ifp) || !(route->ro_rt->rt_flags & RTF_UP))) { /* * If the destination address belongs to a proxied * prefix, relax the requirement and allow the packet * to come out of the proxy interface with the source * address of the real interface. */ if (ifa != NULL && proxied_ifa && (route->ro_rt->rt_flags & (RTF_UP|RTF_PROXY)) == (RTF_UP|RTF_PROXY)) { srcif_selected = TRUE; } else { if (ip6_select_srcif_debug) { if (ifa != NULL) { printf("%s->%s ifscope %d " "ro_if %s != ifa_if %s " "(cached route cleared)\n", s_src, s_dst, ifscope, if_name(ifp), if_name(ifa->ifa_ifp)); } else { printf("%s->%s ifscope %d " "ro_if %s (no ifa_if " "found)\n", s_src, s_dst, ifscope, if_name(ifp)); } } RT_UNLOCK(route->ro_rt); rtfree(route->ro_rt); route->ro_rt = NULL; route->ro_flags &= ~ROF_SRCIF_SELECTED; error = EHOSTUNREACH; /* Undo the settings done above */ route = NULL; ifp = NULL; /* ditch ifp; keep ifp0 */ has_route = FALSE; } } else if (has_route) { srcif_selected = TRUE; } if (srcif_selected) { VERIFY(has_route); route->ro_flags |= ROF_SRCIF_SELECTED; route->ro_rt->generation_id = route_generation; RT_UNLOCK(route->ro_rt); } } else { if (ro->ro_rt != NULL) RT_UNLOCK(ro->ro_rt); if (ifp != NULL && opts != NULL && opts->ip6po_pktinfo != NULL && opts->ip6po_pktinfo->ipi6_ifindex != 0) { /* * Check if the outgoing interface conflicts with the * interface specified by ipi6_ifindex (if specified). * Note that loopback interface is always okay. * (this may happen when we are sending a packet to * one of our own addresses.) */ if (!(ifp->if_flags & IFF_LOOPBACK) && ifp->if_index != opts->ip6po_pktinfo->ipi6_ifindex) { error = EHOSTUNREACH; goto done; } } } done: if (error == 0) { if ((ip6oa->ip6oa_flags & IP6OAF_NO_CELLULAR) && ((ifp != NULL && ifp->if_type == IFT_CELLULAR) || (route != NULL && route->ro_rt != NULL && route->ro_rt->rt_ifp->if_type == IFT_CELLULAR))) { if (route != NULL && route->ro_rt != NULL) { rtfree(route->ro_rt); route->ro_rt = NULL; route->ro_flags &= ~ROF_SRCIF_SELECTED; route = NULL; } ifp = NULL; /* ditch ifp; keep ifp0 */ error = EHOSTUNREACH; } } if (ifp == NULL && (route == NULL || route->ro_rt == NULL)) { /* * This can happen if the caller did not pass a cached route * nor any other hints. We treat this case an error. */ error = EHOSTUNREACH; } if (error == EHOSTUNREACH) ip6stat.ip6s_noroute++; /* * We'll return ifp regardless of error, so pick it up from ifp0 * in case it was nullified above. Caller is responsible for * releasing the ifp if it is non-NULL. */ ifp = ifp0; if (retifp != NULL) { if (ifp != NULL) ifnet_reference(ifp); /* for caller */ *retifp = ifp; } if (error == 0) { if (retrt != NULL && route != NULL) *retrt = route->ro_rt; /* ro_rt may be NULL */ } else if (select_srcif && ip6_select_srcif_debug) { printf("%s->%s ifscope %d ifa_if %s ro_if %s (error=%d)\n", s_src, s_dst, ifscope, (ifa != NULL) ? if_name(ifa->ifa_ifp) : "NONE", (ifp != NULL) ? if_name(ifp) : "NONE", error); } if (ifa != NULL) IFA_REMREF(ifa); return (error); } /* * Regardless of error, it will return an ifp with a reference held if the * caller provides a non-NULL retifp. The caller is responsible for checking * if the returned ifp is valid and release its reference at all times. */ static int in6_selectif(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, struct ip6_moptions *mopts, struct route_in6 *ro, const struct ip6_out_args *ip6oa, struct ifnet **retifp) { int err = 0; struct route_in6 sro; struct rtentry *rt = NULL; if (ro == NULL) { bzero(&sro, sizeof(sro)); ro = &sro; } if ((err = selectroute(NULL, dstsock, opts, mopts, ro, retifp, &rt, 0, 1, ip6oa)) != 0) goto done; /* * do not use a rejected or black hole route. * XXX: this check should be done in the L2 output routine. * However, if we skipped this check here, we'd see the following * scenario: * - install a rejected route for a scoped address prefix * (like fe80::/10) * - send a packet to a destination that matches the scoped prefix, * with ambiguity about the scope zone. * - pick the outgoing interface from the route, and disambiguate the * scope zone with the interface. * - ip6_output() would try to get another route with the "new" * destination, which may be valid. * - we'd see no error on output. * Although this may not be very harmful, it should still be confusing. * We thus reject the case here. */ if (rt && (rt->rt_flags & (RTF_REJECT | RTF_BLACKHOLE))) { err = ((rt->rt_flags & RTF_HOST) ? EHOSTUNREACH : ENETUNREACH); goto done; } /* * Adjust the "outgoing" interface. If we're going to loop the packet * back to ourselves, the ifp would be the loopback interface. * However, we'd rather know the interface associated to the * destination address (which should probably be one of our own * addresses.) */ if (rt != NULL && rt->rt_ifa != NULL && rt->rt_ifa->ifa_ifp != NULL && retifp != NULL) { ifnet_reference(rt->rt_ifa->ifa_ifp); if (*retifp != NULL) ifnet_release(*retifp); *retifp = rt->rt_ifa->ifa_ifp; } done: if (ro == &sro && rt && rt == sro.ro_rt) rtfree(rt); /* * retifp might point to a valid ifp with a reference held; * caller is responsible for releasing it if non-NULL. */ return (err); } /* * Regardless of error, it will return an ifp with a reference held if the * caller provides a non-NULL retifp. The caller is responsible for checking * if the returned ifp is valid and release its reference at all times. * * clone - meaningful only for bsdi and freebsd */ int in6_selectroute(struct sockaddr_in6 *srcsock, struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, struct ip6_moptions *mopts, struct route_in6 *ro, struct ifnet **retifp, struct rtentry **retrt, int clone, const struct ip6_out_args *ip6oa) { return (selectroute(srcsock, dstsock, opts, mopts, ro, retifp, retrt, clone, 0, ip6oa)); } /* * Default hop limit selection. The precedence is as follows: * 1. Hoplimit value specified via ioctl. * 2. (If the outgoing interface is detected) the current * hop limit of the interface specified by router advertisement. * 3. The system default hoplimit. */ int in6_selecthlim( struct in6pcb *in6p, struct ifnet *ifp) { if (in6p && in6p->in6p_hops >= 0) { return(in6p->in6p_hops); } else { lck_rw_lock_shared(nd_if_rwlock); if (ifp && ifp->if_index < nd_ifinfo_indexlim) { u_int8_t chlim; struct nd_ifinfo *ndi = &nd_ifinfo[ifp->if_index]; if (ndi->initialized) { lck_mtx_lock(&ndi->lock); chlim = ndi->chlim; lck_mtx_unlock(&ndi->lock); } else { chlim = ip6_defhlim; } lck_rw_done(nd_if_rwlock); return (chlim); } else { lck_rw_done(nd_if_rwlock); return(ip6_defhlim); } } } /* * XXX: this is borrowed from in6_pcbbind(). If possible, we should * share this function by all *bsd*... */ int in6_pcbsetport( __unused struct in6_addr *laddr, struct inpcb *inp, struct proc *p, int locked) { struct socket *so = inp->inp_socket; u_int16_t lport = 0, first, last, *lastport; int count, error = 0, wild = 0; struct inpcbinfo *pcbinfo = inp->inp_pcbinfo; kauth_cred_t cred; if (!locked) { /* Make sure we don't run into a deadlock: 4052373 */ if (!lck_rw_try_lock_exclusive(pcbinfo->mtx)) { socket_unlock(inp->inp_socket, 0); lck_rw_lock_exclusive(pcbinfo->mtx); socket_lock(inp->inp_socket, 0); } } /* XXX: this is redundant when called from in6_pcbbind */ if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0) wild = INPLOOKUP_WILDCARD; inp->inp_flags |= INP_ANONPORT; if (inp->inp_flags & INP_HIGHPORT) { first = ipport_hifirstauto; /* sysctl */ last = ipport_hilastauto; lastport = &pcbinfo->lasthi; } else if (inp->inp_flags & INP_LOWPORT) { cred = kauth_cred_proc_ref(p); error = priv_check_cred(cred, PRIV_NETINET_RESERVEDPORT, 0); kauth_cred_unref(&cred); if (error != 0) { if (!locked) lck_rw_done(pcbinfo->mtx); return error; } first = ipport_lowfirstauto; /* 1023 */ last = ipport_lowlastauto; /* 600 */ lastport = &pcbinfo->lastlow; } else { first = ipport_firstauto; /* sysctl */ last = ipport_lastauto; lastport = &pcbinfo->lastport; } /* * Simple check to ensure all ports are not used up causing * a deadlock here. * * We split the two cases (up and down) so that the direction * is not being tested on each round of the loop. */ if (first > last) { /* * counting down */ count = first - last; do { if (count-- < 0) { /* completely used? */ /* * Undo any address bind that may have * occurred above. */ inp->in6p_laddr = in6addr_any; inp->in6p_last_outifp = NULL; if (!locked) lck_rw_done(pcbinfo->mtx); return (EAGAIN); } --*lastport; if (*lastport > first || *lastport < last) *lastport = first; lport = htons(*lastport); } while (in6_pcblookup_local(pcbinfo, &inp->in6p_laddr, lport, wild)); } else { /* * counting up */ count = last - first; do { if (count-- < 0) { /* completely used? */ /* * Undo any address bind that may have * occurred above. */ inp->in6p_laddr = in6addr_any; inp->in6p_last_outifp = NULL; if (!locked) lck_rw_done(pcbinfo->mtx); return (EAGAIN); } ++*lastport; if (*lastport < first || *lastport > last) *lastport = first; lport = htons(*lastport); } while (in6_pcblookup_local(pcbinfo, &inp->in6p_laddr, lport, wild)); } inp->inp_lport = lport; if (in_pcbinshash(inp, 1) != 0) { inp->in6p_laddr = in6addr_any; inp->inp_lport = 0; inp->in6p_last_outifp = NULL; if (!locked) lck_rw_done(pcbinfo->mtx); return (EAGAIN); } if (!locked) lck_rw_done(pcbinfo->mtx); return(0); } /* * * The followings are implementation of the policy table using a * * simple tail queue. * * XXX such details should be hidden. * * XXX implementation using binary tree should be more efficient. * */ struct addrsel_policyent { TAILQ_ENTRY(addrsel_policyent) ape_entry; struct in6_addrpolicy ape_policy; }; TAILQ_HEAD(addrsel_policyhead, addrsel_policyent); struct addrsel_policyhead addrsel_policytab; static void init_policy_queue(void) { TAILQ_INIT(&addrsel_policytab); } void addrsel_policy_init(void) { /* * Default address selection policy based on RFC 3484 and * draft-arifumi-6man-rfc3484-revise-03. */ static const struct in6_addrpolicy defaddrsel[] = { /* localhost */ { .addr = { .sin6_family = AF_INET6, .sin6_addr = IN6ADDR_LOOPBACK_INIT, .sin6_len = sizeof(struct sockaddr_in6) }, .addrmask = { .sin6_family = AF_INET6, .sin6_addr = IN6MASK128, .sin6_len = sizeof(struct sockaddr_in6) }, .preced = 60, .label = 0 }, /* ULA */ { .addr = { .sin6_family = AF_INET6, .sin6_addr = {{{ 0xfc }}}, .sin6_len = sizeof(struct sockaddr_in6) }, .addrmask = { .sin6_family = AF_INET6, .sin6_addr = IN6MASK7, .sin6_len = sizeof(struct sockaddr_in6) }, .preced = 50, .label = 1 }, /* any IPv6 src */ { .addr = { .sin6_family = AF_INET6, .sin6_addr = IN6ADDR_ANY_INIT, .sin6_len = sizeof(struct sockaddr_in6) }, .addrmask = { .sin6_family = AF_INET6, .sin6_addr = IN6MASK0, .sin6_len = sizeof(struct sockaddr_in6) }, .preced = 40, .label = 2 }, /* any IPv4 src */ { .addr = { .sin6_family = AF_INET6, .sin6_addr = IN6ADDR_V4MAPPED_INIT, .sin6_len = sizeof(struct sockaddr_in6) }, .addrmask = { .sin6_family = AF_INET6, .sin6_addr = IN6MASK96, .sin6_len = sizeof(struct sockaddr_in6) }, .preced = 30, .label = 3 }, /* 6to4 */ { .addr = { .sin6_family = AF_INET6, .sin6_addr = {{{ 0x20, 0x02 }}}, .sin6_len = sizeof(struct sockaddr_in6) }, .addrmask = { .sin6_family = AF_INET6, .sin6_addr = IN6MASK16, .sin6_len = sizeof(struct sockaddr_in6) }, .preced = 20, .label = 4 }, /* Teredo */ { .addr = { .sin6_family = AF_INET6, .sin6_addr = {{{ 0x20, 0x01 }}}, .sin6_len = sizeof(struct sockaddr_in6) }, .addrmask = { .sin6_family = AF_INET6, .sin6_addr = IN6MASK32, .sin6_len = sizeof(struct sockaddr_in6) }, .preced = 10, .label = 5 }, /* v4 compat addresses */ { .addr = { .sin6_family = AF_INET6, .sin6_addr = IN6ADDR_ANY_INIT, .sin6_len = sizeof(struct sockaddr_in6) }, .addrmask = { .sin6_family = AF_INET6, .sin6_addr = IN6MASK96, .sin6_len = sizeof(struct sockaddr_in6) }, .preced = 1, .label = 10 }, /* site-local (deprecated) */ { .addr = { .sin6_family = AF_INET6, .sin6_addr = {{{ 0xfe, 0xc0 }}}, .sin6_len = sizeof(struct sockaddr_in6) }, .addrmask = { .sin6_family = AF_INET6, .sin6_addr = IN6MASK16, .sin6_len = sizeof(struct sockaddr_in6) }, .preced = 1, .label = 11 }, /* 6bone (deprecated) */ { .addr = { .sin6_family = AF_INET6, .sin6_addr = {{{ 0x3f, 0xfe }}}, .sin6_len = sizeof(struct sockaddr_in6) }, .addrmask = { .sin6_family = AF_INET6, .sin6_addr = IN6MASK16, .sin6_len = sizeof(struct sockaddr_in6) }, .preced = 1, .label = 12 }, }; int i; init_policy_queue(); /* initialize the "last resort" policy */ bzero(&defaultaddrpolicy, sizeof(defaultaddrpolicy)); defaultaddrpolicy.label = ADDR_LABEL_NOTAPP; for (i = 0; i < sizeof(defaddrsel) / sizeof(defaddrsel[0]); i++) add_addrsel_policyent(&defaddrsel[i]); } struct in6_addrpolicy * in6_addrsel_lookup_policy(struct sockaddr_in6 *key) { struct in6_addrpolicy *match = NULL; ADDRSEL_LOCK(); match = match_addrsel_policy(key); if (match == NULL) match = &defaultaddrpolicy; else match->use++; ADDRSEL_UNLOCK(); return (match); } static struct in6_addrpolicy * match_addrsel_policy(struct sockaddr_in6 *key) { struct addrsel_policyent *pent; struct in6_addrpolicy *bestpol = NULL, *pol; int matchlen, bestmatchlen = -1; u_char *mp, *ep, *k, *p, m; TAILQ_FOREACH(pent, &addrsel_policytab, ape_entry) { matchlen = 0; pol = &pent->ape_policy; mp = (u_char *)&pol->addrmask.sin6_addr; ep = mp + 16; /* XXX: scope field? */ k = (u_char *)&key->sin6_addr; p = (u_char *)&pol->addr.sin6_addr; for (; mp < ep && *mp; mp++, k++, p++) { m = *mp; if ((*k & m) != *p) goto next; /* not match */ if (m == 0xff) /* short cut for a typical case */ matchlen += 8; else { while (m >= 0x80) { matchlen++; m <<= 1; } } } /* matched. check if this is better than the current best. */ if (bestpol == NULL || matchlen > bestmatchlen) { bestpol = pol; bestmatchlen = matchlen; } next: continue; } return (bestpol); } static int add_addrsel_policyent(const struct in6_addrpolicy *newpolicy) { struct addrsel_policyent *new, *pol; MALLOC(new, struct addrsel_policyent *, sizeof(*new), M_IFADDR, M_WAITOK); ADDRSEL_LOCK(); /* duplication check */ TAILQ_FOREACH(pol, &addrsel_policytab, ape_entry) { if (IN6_ARE_ADDR_EQUAL(&newpolicy->addr.sin6_addr, &pol->ape_policy.addr.sin6_addr) && IN6_ARE_ADDR_EQUAL(&newpolicy->addrmask.sin6_addr, &pol->ape_policy.addrmask.sin6_addr)) { ADDRSEL_UNLOCK(); FREE(new, M_IFADDR); return (EEXIST); /* or override it? */ } } bzero(new, sizeof(*new)); /* XXX: should validate entry */ new->ape_policy = *newpolicy; TAILQ_INSERT_TAIL(&addrsel_policytab, new, ape_entry); ADDRSEL_UNLOCK(); return (0); } #ifdef ENABLE_ADDRSEL static int delete_addrsel_policyent(const struct in6_addrpolicy *key) { struct addrsel_policyent *pol; ADDRSEL_LOCK(); /* search for the entry in the table */ TAILQ_FOREACH(pol, &addrsel_policytab, ape_entry) { if (IN6_ARE_ADDR_EQUAL(&key->addr.sin6_addr, &pol->ape_policy.addr.sin6_addr) && IN6_ARE_ADDR_EQUAL(&key->addrmask.sin6_addr, &pol->ape_policy.addrmask.sin6_addr)) { break; } } if (pol == NULL) { ADDRSEL_UNLOCK(); return (ESRCH); } TAILQ_REMOVE(&addrsel_policytab, pol, ape_entry); FREE(pol, M_IFADDR); pol = NULL; ADDRSEL_UNLOCK(); return (0); } #endif /* ENABLE_ADDRSEL */ int walk_addrsel_policy(int (*callback)(const struct in6_addrpolicy *, void *), void *w) { struct addrsel_policyent *pol; int error = 0; ADDRSEL_LOCK(); TAILQ_FOREACH(pol, &addrsel_policytab, ape_entry) { if ((error = (*callback)(&pol->ape_policy, w)) != 0) { ADDRSEL_UNLOCK(); return (error); } } ADDRSEL_UNLOCK(); return (error); } /* * Subroutines to manage the address selection policy table via sysctl. */ struct walkarg { struct sysctl_req *w_req; }; static int dump_addrsel_policyent(const struct in6_addrpolicy *pol, void *arg) { int error = 0; struct walkarg *w = arg; error = SYSCTL_OUT(w->w_req, pol, sizeof(*pol)); return (error); } static int in6_src_sysctl SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg1, arg2) struct walkarg w; if (req->newptr) return EPERM; bzero(&w, sizeof(w)); w.w_req = req; return (walk_addrsel_policy(dump_addrsel_policyent, &w)); } SYSCTL_NODE(_net_inet6_ip6, IPV6CTL_ADDRCTLPOLICY, addrctlpolicy, CTLFLAG_RD | CTLFLAG_LOCKED, in6_src_sysctl, ""); int in6_src_ioctl(u_long cmd, caddr_t data) { int i; struct in6_addrpolicy ent0; if (cmd != SIOCAADDRCTL_POLICY && cmd != SIOCDADDRCTL_POLICY) return (EOPNOTSUPP); /* check for safety */ bcopy(data, &ent0, sizeof (ent0)); if (ent0.label == ADDR_LABEL_NOTAPP) return (EINVAL); /* check if the prefix mask is consecutive. */ if (in6_mask2len(&ent0.addrmask.sin6_addr, NULL) < 0) return (EINVAL); /* clear trailing garbages (if any) of the prefix address. */ for (i = 0; i < 4; i++) { ent0.addr.sin6_addr.s6_addr32[i] &= ent0.addrmask.sin6_addr.s6_addr32[i]; } ent0.use = 0; switch (cmd) { case SIOCAADDRCTL_POLICY: #ifdef ENABLE_ADDRSEL return (add_addrsel_policyent(&ent0)); #else return (ENOTSUP); #endif case SIOCDADDRCTL_POLICY: #ifdef ENABLE_ADDRSEL return (delete_addrsel_policyent(&ent0)); #else return (ENOTSUP); #endif } return (0); /* XXX: compromise compilers */ } /* * generate kernel-internal form (scopeid embedded into s6_addr16[1]). * If the address scope of is link-local, embed the interface index in the * address. The routine determines our precedence * between advanced API scope/interface specification and basic API * specification. * * this function should be nuked in the future, when we get rid of * embedded scopeid thing. * * XXX actually, it is over-specification to return ifp against sin6_scope_id. * there can be multiple interfaces that belong to a particular scope zone * (in specification, we have 1:N mapping between a scope zone and interfaces). * we may want to change the function to return something other than ifp. */ int in6_embedscope( struct in6_addr *in6, const struct sockaddr_in6 *sin6, struct in6pcb *in6p, struct ifnet **ifpp, struct ip6_pktopts *opt) { struct ifnet *ifp = NULL; u_int32_t scopeid; struct ip6_pktopts *optp = NULL; *in6 = sin6->sin6_addr; scopeid = sin6->sin6_scope_id; if (ifpp != NULL) *ifpp = NULL; /* * don't try to read sin6->sin6_addr beyond here, since the caller may * ask us to overwrite existing sockaddr_in6 */ #ifdef ENABLE_DEFAULT_SCOPE if (scopeid == 0) scopeid = scope6_addr2default(in6); #endif if (IN6_IS_SCOPE_LINKLOCAL(in6)) { struct in6_pktinfo *pi; struct ifnet *im6o_multicast_ifp = NULL; if (in6p != NULL && IN6_IS_ADDR_MULTICAST(in6) && in6p->in6p_moptions != NULL) { IM6O_LOCK(in6p->in6p_moptions); im6o_multicast_ifp = in6p->in6p_moptions->im6o_multicast_ifp; IM6O_UNLOCK(in6p->in6p_moptions); } if (opt) optp = opt; else if (in6p) optp = in6p->in6p_outputopts; /* * KAME assumption: link id == interface id */ ifnet_head_lock_shared(); if (in6p && optp && (pi = optp->ip6po_pktinfo) && pi->ipi6_ifindex) { ifp = ifindex2ifnet[pi->ipi6_ifindex]; in6->s6_addr16[1] = htons(pi->ipi6_ifindex); } else if (in6p && IN6_IS_ADDR_MULTICAST(in6) && in6p->in6p_moptions != NULL && im6o_multicast_ifp != NULL) { ifp = im6o_multicast_ifp; in6->s6_addr16[1] = htons(ifp->if_index); } else if (scopeid) { /* * Since scopeid is unsigned, we only have to check it * against if_index */ if (if_index < scopeid) { ifnet_head_done(); return ENXIO; /* XXX EINVAL? */ } ifp = ifindex2ifnet[scopeid]; /*XXX assignment to 16bit from 32bit variable */ in6->s6_addr16[1] = htons(scopeid & 0xffff); } ifnet_head_done(); if (ifpp != NULL) { if (ifp != NULL) ifnet_reference(ifp); /* for caller */ *ifpp = ifp; } } return 0; } /* * generate standard sockaddr_in6 from embedded form. * touches sin6_addr and sin6_scope_id only. * * this function should be nuked in the future, when we get rid of * embedded scopeid thing. */ int in6_recoverscope( struct sockaddr_in6 *sin6, const struct in6_addr *in6, struct ifnet *ifp) { u_int32_t scopeid; sin6->sin6_addr = *in6; /* * don't try to read *in6 beyond here, since the caller may * ask us to overwrite existing sockaddr_in6 */ sin6->sin6_scope_id = 0; if (IN6_IS_SCOPE_LINKLOCAL(in6)) { /* * KAME assumption: link id == interface id */ scopeid = ntohs(sin6->sin6_addr.s6_addr16[1]); if (scopeid) { /* * sanity check * * Since scopeid is unsigned, we only have to check it * against if_index */ if (if_index < scopeid) return ENXIO; if (ifp && ifp->if_index != scopeid) return ENXIO; sin6->sin6_addr.s6_addr16[1] = 0; sin6->sin6_scope_id = scopeid; } } return 0; }