X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/55e303ae13a4cf49d70f2294092726f2fffb9ef2..bb59bff194111743b33cc36712410b5656329d3c:/bsd/netinet6/in6_src.c?ds=inline diff --git a/bsd/netinet6/in6_src.c b/bsd/netinet6/in6_src.c index 3f9c8e4ff..86b703bf5 100644 --- a/bsd/netinet6/in6_src.c +++ b/bsd/netinet6/in6_src.c @@ -1,5 +1,30 @@ -/* $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) 2000-2014 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@ + */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. @@ -76,8 +101,13 @@ #include #include #include +#include +#include +#include +#include #include +#include #include #include @@ -89,220 +119,1108 @@ #include #include #include +#include #include -#if ENABLE_DEFAULT_SCOPE -#include -#endif #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 in6_ifaddr **, + struct route_in6 *, struct ifnet **, struct rtentry **, int, int, + struct ip6_out_args *ip6oa); +static int in6_selectif(struct sockaddr_in6 *, struct ip6_pktopts *, + struct ip6_moptions *, struct route_in6 *ro, + 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(dstsock, opts, mopts, ro, laddr, errorp) - struct sockaddr_in6 *dstsock; - struct ip6_pktopts *opts; - struct ip6_moptions *mopts; - struct route_in6 *ro; - struct in6_addr *laddr; - int *errorp; +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 in6_ifaddr *ia6 = 0; + 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 ip6_out_args ip6oa = { ifscope, { 0 }, IP6OAF_SELECT_SRCIF, 0 }; + boolean_t islocal = FALSE; + uint64_t secs = net_uptime(); - dst = &dstsock->sin6_addr; + 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_NO_CELLULAR(inp)) + ip6oa.ip6oa_flags |= IP6OAF_NO_CELLULAR; + if (INP_NO_EXPENSIVE(inp)) + ip6oa.ip6oa_flags |= IP6OAF_NO_EXPENSIVE; + if (INP_AWDL_UNRESTRICTED(inp)) + ip6oa.ip6oa_flags |= IP6OAF_AWDL_UNRESTRICTED; + + } 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, - * use it. + * 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)) - return(&pi->ipi6_addr); + !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)) || + (inp && inp_restricted_send(inp, ia6->ia_ifa.ifa_ifp))) { + IFA_UNLOCK(&ia6->ia_ifa); + IFA_REMREF(&ia6->ia_ifa); + *errorp = EHOSTUNREACH; + 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; + } /* - * If the source address is not specified but the socket(if any) - * is already bound, use the bound address. + * Otherwise, if the socket has already bound the source, just use it. */ - if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr)) - return(laddr); + if (inp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) { + src_storage = &inp->in6p_laddr; + goto done; + } /* - * If the caller doesn't specify the source address but - * the outgoing interface, use an address associated with - * the interface. + * If the address is not specified, choose the best one based on + * the outgoing interface and the destination address. */ - if (pi && pi->ipi6_ifindex) { - /* XXX boundary check is assumed to be already done. */ - ia6 = in6_ifawithscope(ifindex2ifnet[pi->ipi6_ifindex], - dst); - if (ia6 == 0) { - *errorp = EADDRNOTAVAIL; - return(0); + + /* 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, secs)) + 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(IP6S_SRCRULE_1); /* there should be no better candidate */ + + if (ia_best == NULL) + REPLACE(IP6S_SRCRULE_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(IP6S_SRCRULE_2); + NEXTSRC(IP6S_SRCRULE_2); + } else if (IN6_ARE_SCOPE_CMP(new_scope, best_scope) < 0) { + if (IN6_ARE_SCOPE_CMP(new_scope, dst_scope) < 0) + NEXTSRC(IP6S_SRCRULE_2); + REPLACE(IP6S_SRCRULE_2); + } + + /* + * Rule 3: Avoid deprecated addresses. Note that the case of + * !ip6_use_deprecated is already rejected above. + */ + if (!IFA6_IS_DEPRECATED(ia_best, secs) && + IFA6_IS_DEPRECATED(ia, secs)) + NEXTSRC(IP6S_SRCRULE_3); + if (IFA6_IS_DEPRECATED(ia_best, secs) && + !IFA6_IS_DEPRECATED(ia, secs)) + REPLACE(IP6S_SRCRULE_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(IP6S_SRCRULE_3); + if ((ia_best->ia6_flags & IN6_IFF_OPTIMISTIC) != 0 && + (ia->ia6_flags & IN6_IFF_OPTIMISTIC) == 0) + REPLACE(IP6S_SRCRULE_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(IP6S_SRCRULE_5); + if (ia_best->ia_ifp != ifp && ia->ia_ifp == ifp) + REPLACE(IP6S_SRCRULE_5); + + /* Rule 5.5: Prefer addresses in a prefix advertised by the next hop. */ + if (ro != NULL && ro->ro_rt != NULL && ia_best->ia6_ndpr != NULL && + ia->ia6_ndpr != NULL) { + struct rtentry *rta, *rtb; + int op; + + NDPR_LOCK(ia_best->ia6_ndpr); + rta = ia_best->ia6_ndpr->ndpr_rt; + if (rta != NULL) + RT_ADDREF(rta); + NDPR_UNLOCK(ia_best->ia6_ndpr); + + NDPR_LOCK(ia->ia6_ndpr); + rtb = ia->ia6_ndpr->ndpr_rt; + if (rtb != NULL) + RT_ADDREF(rtb); + NDPR_UNLOCK(ia->ia6_ndpr); + + if (rta == NULL || rtb == NULL) + op = 0; + else if (rta == ro->ro_rt && rtb != ro->ro_rt) + op = 1; + else if (rta != ro->ro_rt && rtb == ro->ro_rt) + op = 2; + else + op = 0; + + if (rta != NULL) + RT_REMREF(rta); + if (rtb != NULL) + RT_REMREF(rtb); + + switch (op) { + case 1: + NEXTSRC(IP6S_SRCRULE_5_5); + break; + case 2: + REPLACE(IP6S_SRCRULE_5_5); + break; + default: + break; + } + } + + /* + * 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(IP6S_SRCRULE_6); + if (dst_policy->label != best_policy->label && + dst_policy->label == new_policy->label) + REPLACE(IP6S_SRCRULE_6); + } + + /* + * Rule 7: Prefer temporary addresses. + * We allow users to reverse the logic by configuring + * a sysctl variable, so that transparency conscious users can + * always prefer stable 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) >= + ia_best->ia_plen) + 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(IP6S_SRCRULE_7); + else + NEXTSRC(IP6S_SRCRULE_7); } - return(&satosin6(&ia6->ia_addr)->sin6_addr); + if ((ia_best->ia6_flags & IN6_IFF_TEMPORARY) && + !(ia->ia6_flags & IN6_IFF_TEMPORARY)) { + if (prefer_tempaddr) + NEXTSRC(IP6S_SRCRULE_7); + else + REPLACE(IP6S_SRCRULE_7); + } + + /* + * Rule 7x: 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(IP6S_SRCRULE_7x); + if (!(ia_best->ia_ifp->if_flags & IFF_UP) && + (ia->ia_ifp->if_flags & IFF_UP)) + REPLACE(IP6S_SRCRULE_7x); + + /* + * Rule 8: Use longest matching prefix. + */ + new_matchlen = in6_matchlen(&ia->ia_addr.sin6_addr, &dst); + if (best_matchlen < new_matchlen) + REPLACE(IP6S_SRCRULE_8); + if (new_matchlen < best_matchlen) + NEXTSRC(IP6S_SRCRULE_8); + + /* + * 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 && inp && + inp_restricted_send(inp, ia_best->ia_ifa.ifa_ifp)) { + IFA_REMREF(&ia_best->ia_ifa); + ia_best = NULL; + *errorp = EHOSTUNREACH; + } + + if ((ia = ia_best) == NULL) { + if (*errorp == 0) + *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 in6_ifaddr **retsrcia, struct route_in6 *ro, + struct ifnet **retifp, struct rtentry **retrt, int clone, + int norouteok, 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, local_dst = FALSE; + unsigned int ifscope = ((ip6oa != NULL) ? + ip6oa->ip6oa_boundif : IFSCOPE_NONE); + +#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; } /* - * If the destination address is a link-local unicast address or - * a multicast address, and if the outgoing interface is specified - * by the sin6_scope_id filed, use an address associated with the - * interface. - * XXX: We're now trying to define more specific semantics of - * sin6_scope_id field, so this part will be rewritten in - * the near future. + * Perform source interface selection only if Scoped Routing + * is enabled and a source address that isn't unspecified. */ - if ((IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MULTICAST(dst)) && - dstsock->sin6_scope_id) { + 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) { /* - * I'm not sure if boundary check for scope_id is done - * somewhere... + * If IPV6_PKTINFO takes precedence over IPV6_BOUND_IF. */ - if (dstsock->sin6_scope_id < 0 || - if_index < dstsock->sin6_scope_id) { - *errorp = ENXIO; /* XXX: better error? */ - return(0); - } - ia6 = in6_ifawithscope(ifindex2ifnet[dstsock->sin6_scope_id], - dst); - if (ia6 == 0) { - *errorp = EADDRNOTAVAIL; - return(0); + 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; } - return(&satosin6(&ia6->ia_addr)->sin6_addr); } /* - * If the destination address is a multicast address and - * the outgoing interface for the address is specified - * by the caller, use an address associated with the interface. - * There is a sanity check here; if the destination has node-local - * scope, the outgoing interfacde should be a loopback address. - * Even if the outgoing interface is not specified, we also - * choose a loopback interface as the outgoing interface. + * 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)) { - struct ifnet *ifp = mopts ? mopts->im6o_multicast_ifp : NULL; + 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; - if (ifp == NULL && IN6_IS_ADDR_MC_NODELOCAL(dst)) { - ifp = &loif[0]; + /* + * 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) { + goto getroute; + } else if (!ROUTE_UNUSABLE(ro) && ro->ro_srcia != NULL && + (ro->ro_flags & ROF_SRCIF_SELECTED)) { + if (ro->ro_rt->rt_ifp->if_flags & IFF_LOOPBACK) + local_dst = TRUE; + ifa = ro->ro_srcia; + IFA_ADDREF(ifa); /* for caller */ + 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) && + ROUTE_UNUSABLE(ro)) + 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 (ifp) { - ia6 = in6_ifawithscope(ifp, dst); - if (ia6 == 0) { - *errorp = EADDRNOTAVAIL; - return(0); + 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)); } - return(&satosin6(&ia6->ia_addr)->sin6_addr); } } /* - * If the next hop address for the packet is specified - * by caller, use an address associated with the route - * to the next hop. + * 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. */ - { - struct sockaddr_in6 *sin6_next; - struct rtentry *rt; - - if (opts && opts->ip6po_nexthop) { - sin6_next = satosin6(opts->ip6po_nexthop); - rt = nd6_lookup(&sin6_next->sin6_addr, 1, NULL); - if (rt) { - ia6 = in6_ifawithscope(rt->rt_ifp, dst); - if (ia6 == 0) - ia6 = ifatoia6(rt->rt_ifa); - } - if (ia6 == 0) { - *errorp = EADDRNOTAVAIL; - return(0); - } - return(&satosin6(&ia6->ia_addr)->sin6_addr); + if (ifa == NULL && ifscope == IFSCOPE_NONE) { + struct ifaddr *ifadst; + + /* Check if the destination address is one of ours */ + ifadst = (struct ifaddr *)ifa_foraddr6(&dstsock->sin6_addr); + if (ifadst != NULL) { + local_dst = TRUE; + IFA_REMREF(ifadst); } + + 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 && !local_dst) + ifscope = ifa->ifa_ifp->if_index; + /* - * If route is known or can be allocated now, - * our src addr is taken from the i/f, else punt. + * If the next hop address for the packet is specified by the caller, + * use it as the gateway. */ - if (ro) { - if (ro->ro_rt && - (!(ro->ro_rt->rt_flags & RTF_UP) || - satosin6(&ro->ro_dst)->sin6_family != AF_INET6 || - !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, - dst))) { - rtfree(ro->ro_rt); - ro->ro_rt = (struct rtentry *)0; - } - if (ro->ro_rt == (struct rtentry *)0 || - ro->ro_rt->rt_ifp == (struct ifnet *)0) { - struct sockaddr_in6 *sa6; - - /* 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; - sa6->sin6_scope_id = dstsock->sin6_scope_id; - if (IN6_IS_ADDR_MULTICAST(dst)) { - ro->ro_rt = rtalloc1(&((struct route *)ro) - ->ro_dst, 0, 0UL); - } else { - rtalloc((struct route *)ro); - } + 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; } /* - * in_pcbconnect() checks out IFF_LOOPBACK to skip using - * the address. But we don't know why it does so. - * It is necessary to ensure the scope even for lo0 - * so doesn't check out IFF_LOOPBACK. + * 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 (ROUTE_UNUSABLE(ron) || (ron->ro_rt != NULL && + (!(ron->ro_rt->rt_flags & RTF_LLINFO) || + (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); - if (ro->ro_rt) { - ia6 = in6_ifawithscope(ro->ro_rt->rt_ifa->ifa_ifp, dst); - if (ia6 == 0) /* xxx scope error ?*/ - ia6 = ifatoia6(ro->ro_rt->rt_ifa); + ROUTE_RELEASE(ron); + *satosin6(&ron->ro_dst) = *sin6_next; } -#if 0 + if (ron->ro_rt == NULL) { + rtalloc_scoped((struct route *)ron, ifscope); + if (ron->ro_rt != NULL) + RT_LOCK(ron->ro_rt); + if (ROUTE_UNUSABLE(ron) || + !(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); + + ROUTE_RELEASE(ron); + error = EHOSTUNREACH; + goto done; + } + } + route = ron; + ifp = ifp0 = ron->ro_rt->rt_ifp; + /* - * xxx The followings are necessary? (kazu) - * I don't think so. - * It's for SO_DONTROUTE option in IPv4.(jinmei) + * When cloning is required, try to allocate a route to the + * destination so that the caller can store path MTU + * information. */ - if (ia6 == 0) { - struct sockaddr_in6 sin6 = {sizeof(sin6), AF_INET6, 0}; + 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_SPIN(ro->ro_rt); + if (ROUTE_UNUSABLE(ro) || (ro->ro_rt != NULL && + (satosin6(&ro->ro_dst)->sin6_family != AF_INET6 || + !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)))))) { + if (ro->ro_rt != NULL) + RT_UNLOCK(ro->ro_rt); - sin6->sin6_addr = *dst; + ROUTE_RELEASE(ro); + } + if (ro->ro_rt == NULL) { + struct sockaddr_in6 *sa6; - ia6 = ifatoia6(ifa_ifwithdstaddr(sin6tosa(&sin6))); - if (ia6 == 0) - ia6 = ifatoia6(ifa_ifwithnet(sin6tosa(&sin6))); - if (ia6 == 0) - return(0); - return(&satosin6(&ia6->ia_addr)->sin6_addr); + 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); } -#endif /* 0 */ - if (ia6 == 0) { - *errorp = EHOSTUNREACH; /* no route */ - return(0); + if (ro->ro_rt != NULL) + RT_LOCK_SPIN(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); + ROUTE_RELEASE(route); + 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); + if (ifa != route->ro_srcia || + !(route->ro_flags & ROF_SRCIF_SELECTED)) { + RT_CONVERT_LOCK(route->ro_rt); + if (ifa != NULL) + IFA_ADDREF(ifa); /* for route_in6 */ + if (route->ro_srcia != NULL) + IFA_REMREF(route->ro_srcia); + route->ro_srcia = ifa; + route->ro_flags |= ROF_SRCIF_SELECTED; + RT_GENID_SYNC(route->ro_rt); + } + 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; + } } - return(&satosin6(&ia6->ia_addr)->sin6_addr); } - *errorp = EADDRNOTAVAIL; - return(0); +done: + /* + * Check for interface restrictions. + */ +#define CHECK_RESTRICTIONS(_ip6oa, _ifp) \ + ((((_ip6oa)->ip6oa_flags & IP6OAF_NO_CELLULAR) && \ + IFNET_IS_CELLULAR(_ifp)) || \ + (((_ip6oa)->ip6oa_flags & IP6OAF_NO_EXPENSIVE) && \ + IFNET_IS_EXPENSIVE(_ifp)) || \ + (!((_ip6oa)->ip6oa_flags & IP6OAF_AWDL_UNRESTRICTED) && \ + IFNET_IS_AWDL_RESTRICTED(_ifp))) + + if (error == 0 && ip6oa != NULL && + ((ifp && CHECK_RESTRICTIONS(ip6oa, ifp)) || + (route && route->ro_rt && + CHECK_RESTRICTIONS(ip6oa, route->ro_rt->rt_ifp)))) { + if (route != NULL && route->ro_rt != NULL) { + ROUTE_RELEASE(route); + route = NULL; + } + ifp = NULL; /* ditch ifp; keep ifp0 */ + error = EHOSTUNREACH; + ip6oa->ip6oa_retflags |= IP6OARF_IFDENIED; + } +#undef CHECK_RESTRICTIONS + + /* + * If the interface is disabled for IPv6, then ENETDOWN error. + */ + if (error == 0 && + ifp != NULL && (ifp->if_eflags & IFEF_IPV6_DISABLED)) { + error = ENETDOWN; + } + + 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 || error == ENETDOWN) + 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 (retsrcia != NULL) { + if (ifa != NULL) + IFA_ADDREF(ifa); /* for caller */ + *retsrcia = (struct in6_ifaddr *)ifa; + } + + 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, + 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, NULL, 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) { + VERIFY(rt == NULL || rt == ro->ro_rt); + ROUTE_RELEASE(ro); + } + + /* + * 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 in6_ifaddr **retsrcia, struct route_in6 *ro, struct ifnet **retifp, + struct rtentry **retrt, int clone, struct ip6_out_args *ip6oa) +{ + + return (selectroute(srcsock, dstsock, opts, mopts, retsrcia, ro, retifp, + retrt, clone, 0, ip6oa)); } /* @@ -311,18 +1229,31 @@ in6_selectsrc(dstsock, opts, mopts, ro, laddr, errorp) * 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(in6p, ifp) - struct in6pcb *in6p; - struct ifnet *ifp; +in6_selecthlim(struct in6pcb *in6p, struct ifnet *ifp) { - if (in6p && in6p->in6p_hops >= 0) - return(in6p->in6p_hops); - else if (ifp) - return(nd_ifinfo[ifp->if_index].chlim); - else - return(ip6_defhlim); + 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) { + /* access chlim without lock, for performance */ + chlim = ndi->chlim; + } else { + chlim = ip6_defhlim; + } + lck_rw_done(nd_if_rwlock); + return (chlim); + } else { + lck_rw_done(nd_if_rwlock); + return (ip6_defhlim); + } + } } /* @@ -330,41 +1261,62 @@ in6_selecthlim(in6p, ifp) * share this function by all *bsd*... */ int -in6_pcbsetport(laddr, inp, p) - struct in6_addr *laddr; - struct inpcb *inp; - struct proc *p; +in6_pcbsetport(struct in6_addr *laddr, struct inpcb *inp, struct proc *p, + int locked) { +#pragma unused(laddr) 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->ipi_lock)) { + socket_unlock(inp->inp_socket, 0); + lck_rw_lock_exclusive(pcbinfo->ipi_lock); + socket_lock(inp->inp_socket, 0); + } + + /* + * Check if a local port was assigned to the inp while + * this thread was waiting for the pcbinfo lock + */ + if (inp->inp_lport != 0) { + VERIFY(inp->inp_flags2 & INP2_INHASHLIST); + lck_rw_done(pcbinfo->ipi_lock); + + /* + * It is not an error if another thread allocated + * a port + */ + return (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; + lastport = &pcbinfo->ipi_lasthi; } else if (inp->inp_flags & INP_LOWPORT) { -#ifdef __APPLE__ - if (p && (error = suser(p->p_ucred, &p->p_acflag))) -#else - if (p && (error = suser(p))) -#endif - - return error; + 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->ipi_lock); + return (error); + } first = ipport_lowfirstauto; /* 1023 */ last = ipport_lowlastauto; /* 600 */ - lastport = &pcbinfo->lastlow; + lastport = &pcbinfo->ipi_lastlow; } else { first = ipport_firstauto; /* sysctl */ last = ipport_lastauto; - lastport = &pcbinfo->lastport; + lastport = &pcbinfo->ipi_lastport; } /* * Simple check to ensure all ports are not used up causing @@ -386,18 +1338,19 @@ in6_pcbsetport(laddr, inp, p) * occurred above. */ inp->in6p_laddr = in6addr_any; + inp->in6p_last_outifp = NULL; + if (!locked) + lck_rw_done(pcbinfo->ipi_lock); return (EAGAIN); } --*lastport; if (*lastport > first || *lastport < last) *lastport = first; lport = htons(*lastport); - } while (in6_pcblookup_local(pcbinfo, - &inp->in6p_laddr, lport, wild)); + } while (in6_pcblookup_local(pcbinfo, &inp->in6p_laddr, lport, + wild)); } else { - /* - * counting up - */ + /* counting up */ count = last - first; do { @@ -407,24 +1360,440 @@ in6_pcbsetport(laddr, inp, p) * occurred above. */ inp->in6p_laddr = in6addr_any; + inp->in6p_last_outifp = NULL; + if (!locked) + lck_rw_done(pcbinfo->ipi_lock); return (EAGAIN); } ++*lastport; if (*lastport < first || *lastport > last) *lastport = first; lport = htons(*lastport); - } while (in6_pcblookup_local(pcbinfo, - &inp->in6p_laddr, lport, wild)); + } while (in6_pcblookup_local(pcbinfo, &inp->in6p_laddr, lport, + wild)); } inp->inp_lport = lport; - if (in_pcbinshash(inp) != 0) { + inp->inp_flags |= INP_ANONPORT; + + if (in_pcbinshash(inp, 1) != 0) { inp->in6p_laddr = in6addr_any; + inp->in6p_last_outifp = NULL; + inp->inp_lport = 0; + inp->inp_flags &= ~INP_ANONPORT; + if (!locked) + lck_rw_done(pcbinfo->ipi_lock); return (EAGAIN); } - return(0); + if (!locked) + lck_rw_done(pcbinfo->ipi_lock); + 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 6724. + */ + static const struct in6_addrpolicy defaddrsel[] = { + /* Loopback -- prefix=::1/128, precedence=50, label=0 */ + { + .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 = 50, + .label = 0 + }, + + /* Unspecified -- prefix=::/0, precedence=40, label=1 */ + { + .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 = 1 + }, + + /* IPv4 Mapped -- prefix=::ffff:0:0/96, precedence=35, label=4 */ + { + .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 = 35, + .label = 4 + }, + + /* 6to4 -- prefix=2002::/16, precedence=30, label=2 */ + { + .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 = 30, + .label = 2 + }, + + /* Teredo -- prefix=2001::/32, precedence=5, label=5 */ + { + .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 = 5, + .label = 5 + }, + + /* Unique Local (ULA) -- prefix=fc00::/7, precedence=3, label=13 */ + { + .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 = 3, + .label = 13 + }, + + /* IPv4 Compatible -- prefix=::/96, precedence=1, label=3 */ + { + .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 = 3 + }, + + /* Site-local (deprecated) -- prefix=fec0::/10, precedence=1, label=11 */ + { + .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) -- prefix=3ffe::/16, precedence=1, label=12 */ + { + .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 */ } /* @@ -443,24 +1812,16 @@ in6_pcbsetport(laddr, inp, p) * we may want to change the function to return something other than ifp. */ int -in6_embedscope(in6, sin6, in6p, ifpp) - struct in6_addr *in6; - const struct sockaddr_in6 *sin6; -#ifdef HAVE_NRL_INPCB - struct inpcb *in6p; -#define in6p_outputopts inp_outputopts6 -#define in6p_moptions inp_moptions6 -#else - struct in6pcb *in6p; -#endif - struct ifnet **ifpp; +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) + if (ifpp != NULL) *ifpp = NULL; /* @@ -473,42 +1834,67 @@ in6_embedscope(in6, sin6, in6p, ifpp) scopeid = scope6_addr2default(in6); #endif - if (IN6_IS_SCOPE_LINKLOCAL(in6)) { + if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(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 != NULL) + optp = opt; + else if (in6p != NULL) + optp = in6p->in6p_outputopts; /* * KAME assumption: link id == interface id */ - - if (in6p && in6p->in6p_outputopts && - (pi = in6p->in6p_outputopts->ip6po_pktinfo) && - pi->ipi6_ifindex) { - ifp = ifindex2ifnet[pi->ipi6_ifindex]; + if (in6p != NULL && optp != NULL && + (pi = optp->ip6po_pktinfo) != NULL && + pi->ipi6_ifindex != 0) { + /* ifp is needed here if only we're returning it */ + if (ifpp != NULL) { + ifnet_head_lock_shared(); + ifp = ifindex2ifnet[pi->ipi6_ifindex]; + ifnet_head_done(); + } in6->s6_addr16[1] = htons(pi->ipi6_ifindex); - } else if (in6p && IN6_IS_ADDR_MULTICAST(in6) && - in6p->in6p_moptions && - in6p->in6p_moptions->im6o_multicast_ifp) { - ifp = in6p->in6p_moptions->im6o_multicast_ifp; + } else if (in6p != NULL && 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) { - /* boundary check */ - if (scopeid < 0 || if_index < scopeid) - return ENXIO; /* XXX EINVAL? */ - ifp = ifindex2ifnet[scopeid]; - /*XXX assignment to 16bit from 32bit variable */ + } else if (scopeid != 0) { + /* + * Since scopeid is unsigned, we only have to check it + * against if_index (ifnet_head_lock not needed since + * if_index is an ever-increasing integer.) + */ + if (if_index < scopeid) + return (ENXIO); /* XXX EINVAL? */ + + /* ifp is needed here only if we're returning it */ + if (ifpp != NULL) { + ifnet_head_lock_shared(); + ifp = ifindex2ifnet[scopeid]; + ifnet_head_done(); + } + /* XXX assignment to 16bit from 32bit variable */ in6->s6_addr16[1] = htons(scopeid & 0xffff); } - if (ifpp) + if (ifpp != NULL) { + if (ifp != NULL) + ifnet_reference(ifp); /* for caller */ *ifpp = ifp; + } } - return 0; + return (0); } -#if HAVE_NRL_INPCB -#undef in6p_outputopts -#undef in6p_moptions -#endif /* * generate standard sockaddr_in6 from embedded form. @@ -518,10 +1904,10 @@ in6_embedscope(in6, sin6, in6p, ifpp) * embedded scopeid thing. */ int -in6_recoverscope(sin6, in6, ifp) - struct sockaddr_in6 *sin6; - const struct in6_addr *in6; - struct ifnet *ifp; +in6_recoverscope( + struct sockaddr_in6 *sin6, + const struct in6_addr *in6, + struct ifnet *ifp) { u_int32_t scopeid; @@ -533,33 +1919,26 @@ in6_recoverscope(sin6, in6, ifp) */ sin6->sin6_scope_id = 0; - if (IN6_IS_SCOPE_LINKLOCAL(in6)) { + if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { /* * KAME assumption: link id == interface id */ scopeid = ntohs(sin6->sin6_addr.s6_addr16[1]); if (scopeid) { - /* sanity check */ - if (scopeid < 0 || if_index < scopeid) - return ENXIO; + /* + * 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; + return (ENXIO); sin6->sin6_addr.s6_addr16[1] = 0; sin6->sin6_scope_id = scopeid; } } - return 0; -} - -/* - * just clear the embedded scope identifer. - * XXX: currently used for bsdi4 only as a supplement function. - */ -void -in6_clearscope(addr) - struct in6_addr *addr; -{ - if (IN6_IS_SCOPE_LINKLOCAL(addr)) - addr->s6_addr16[1] = 0; + return (0); }