From bceabc95c1c85d793200446fa85f1ddc6313ea29 Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Wed, 9 Oct 2013 22:42:09 +0200 Subject: Move files to match FreeBSD layout --- freebsd/sys/netinet6/nd6.c | 2249 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 2249 insertions(+) create mode 100644 freebsd/sys/netinet6/nd6.c (limited to 'freebsd/sys/netinet6/nd6.c') diff --git a/freebsd/sys/netinet6/nd6.c b/freebsd/sys/netinet6/nd6.c new file mode 100644 index 00000000..bc7ed57e --- /dev/null +++ b/freebsd/sys/netinet6/nd6.c @@ -0,0 +1,2249 @@ +#include + +/*- + * 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. + * + * $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $ + */ + +#include +__FBSDID("$FreeBSD$"); + +#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 +#define L3_ADDR_SIN6(le) ((struct sockaddr_in6 *) L3_ADDR(le)) +#include +#include +#include +#include +#include +#include +#include + +#include + +#include + +#define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */ +#define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */ + +#define SIN6(s) ((struct sockaddr_in6 *)s) + +/* timer values */ +VNET_DEFINE(int, nd6_prune) = 1; /* walk list every 1 seconds */ +VNET_DEFINE(int, nd6_delay) = 5; /* delay first probe time 5 second */ +VNET_DEFINE(int, nd6_umaxtries) = 3; /* maximum unicast query */ +VNET_DEFINE(int, nd6_mmaxtries) = 3; /* maximum multicast query */ +VNET_DEFINE(int, nd6_useloopback) = 1; /* use loopback interface for + * local traffic */ +VNET_DEFINE(int, nd6_gctimer) = (60 * 60 * 24); /* 1 day: garbage + * collection timer */ + +/* preventing too many loops in ND option parsing */ +static VNET_DEFINE(int, nd6_maxndopt) = 10; /* max # of ND options allowed */ + +VNET_DEFINE(int, nd6_maxnudhint) = 0; /* max # of subsequent upper + * layer hints */ +static VNET_DEFINE(int, nd6_maxqueuelen) = 1; /* max pkts cached in unresolved + * ND entries */ +#define V_nd6_maxndopt VNET(nd6_maxndopt) +#define V_nd6_maxqueuelen VNET(nd6_maxqueuelen) + +#ifdef ND6_DEBUG +VNET_DEFINE(int, nd6_debug) = 1; +#else +VNET_DEFINE(int, nd6_debug) = 0; +#endif + +/* for debugging? */ +#if 0 +static int nd6_inuse, nd6_allocated; +#endif + +VNET_DEFINE(struct nd_drhead, nd_defrouter); +VNET_DEFINE(struct nd_prhead, nd_prefix); + +VNET_DEFINE(int, nd6_recalc_reachtm_interval) = ND6_RECALC_REACHTM_INTERVAL; +#define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval) + +static struct sockaddr_in6 all1_sa; + +static int nd6_is_new_addr_neighbor __P((struct sockaddr_in6 *, + struct ifnet *)); +static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *); +static void nd6_slowtimo(void *); +static int regen_tmpaddr(struct in6_ifaddr *); +static struct llentry *nd6_free(struct llentry *, int); +static void nd6_llinfo_timer(void *); +static void clear_llinfo_pqueue(struct llentry *); + +static VNET_DEFINE(struct callout, nd6_slowtimo_ch); +#define V_nd6_slowtimo_ch VNET(nd6_slowtimo_ch) + +VNET_DEFINE(struct callout, nd6_timer_ch); + +void +nd6_init(void) +{ + int i; + + LIST_INIT(&V_nd_prefix); + + all1_sa.sin6_family = AF_INET6; + all1_sa.sin6_len = sizeof(struct sockaddr_in6); + for (i = 0; i < sizeof(all1_sa.sin6_addr); i++) + all1_sa.sin6_addr.s6_addr[i] = 0xff; + + /* initialization of the default router list */ + TAILQ_INIT(&V_nd_defrouter); + + /* start timer */ + callout_init(&V_nd6_slowtimo_ch, 0); + callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, + nd6_slowtimo, curvnet); +} + +#ifdef VIMAGE +void +nd6_destroy() +{ + + callout_drain(&V_nd6_slowtimo_ch); + callout_drain(&V_nd6_timer_ch); +} +#endif + +struct nd_ifinfo * +nd6_ifattach(struct ifnet *ifp) +{ + struct nd_ifinfo *nd; + + nd = (struct nd_ifinfo *)malloc(sizeof(*nd), M_IP6NDP, M_WAITOK); + bzero(nd, sizeof(*nd)); + + nd->initialized = 1; + + nd->chlim = IPV6_DEFHLIM; + nd->basereachable = REACHABLE_TIME; + nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); + nd->retrans = RETRANS_TIMER; + /* + * Note that the default value of ip6_accept_rtadv is 0, which means + * we won't accept RAs by default even if we set ND6_IFF_ACCEPT_RTADV + * here. + */ + nd->flags = (ND6_IFF_PERFORMNUD | ND6_IFF_ACCEPT_RTADV); + + /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ + nd6_setmtu0(ifp, nd); + + return nd; +} + +void +nd6_ifdetach(struct nd_ifinfo *nd) +{ + + free(nd, M_IP6NDP); +} + +/* + * Reset ND level link MTU. This function is called when the physical MTU + * changes, which means we might have to adjust the ND level MTU. + */ +void +nd6_setmtu(struct ifnet *ifp) +{ + + nd6_setmtu0(ifp, ND_IFINFO(ifp)); +} + +/* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */ +void +nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi) +{ + u_int32_t omaxmtu; + + omaxmtu = ndi->maxmtu; + + switch (ifp->if_type) { + case IFT_ARCNET: + ndi->maxmtu = MIN(ARC_PHDS_MAXMTU, ifp->if_mtu); /* RFC2497 */ + break; + case IFT_FDDI: + ndi->maxmtu = MIN(FDDIIPMTU, ifp->if_mtu); /* RFC2467 */ + break; + case IFT_ISO88025: + ndi->maxmtu = MIN(ISO88025_MAX_MTU, ifp->if_mtu); + break; + default: + ndi->maxmtu = ifp->if_mtu; + break; + } + + /* + * Decreasing the interface MTU under IPV6 minimum MTU may cause + * undesirable situation. We thus notify the operator of the change + * explicitly. The check for omaxmtu is necessary to restrict the + * log to the case of changing the MTU, not initializing it. + */ + if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { + log(LOG_NOTICE, "nd6_setmtu0: " + "new link MTU on %s (%lu) is too small for IPv6\n", + if_name(ifp), (unsigned long)ndi->maxmtu); + } + + if (ndi->maxmtu > V_in6_maxmtu) + in6_setmaxmtu(); /* check all interfaces just in case */ + +} + +void +nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts) +{ + + bzero(ndopts, sizeof(*ndopts)); + ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; + ndopts->nd_opts_last + = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); + + if (icmp6len == 0) { + ndopts->nd_opts_done = 1; + ndopts->nd_opts_search = NULL; + } +} + +/* + * Take one ND option. + */ +struct nd_opt_hdr * +nd6_option(union nd_opts *ndopts) +{ + struct nd_opt_hdr *nd_opt; + int olen; + + if (ndopts == NULL) + panic("ndopts == NULL in nd6_option"); + if (ndopts->nd_opts_last == NULL) + panic("uninitialized ndopts in nd6_option"); + if (ndopts->nd_opts_search == NULL) + return NULL; + if (ndopts->nd_opts_done) + return NULL; + + nd_opt = ndopts->nd_opts_search; + + /* make sure nd_opt_len is inside the buffer */ + if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) { + bzero(ndopts, sizeof(*ndopts)); + return NULL; + } + + olen = nd_opt->nd_opt_len << 3; + if (olen == 0) { + /* + * Message validation requires that all included + * options have a length that is greater than zero. + */ + bzero(ndopts, sizeof(*ndopts)); + return NULL; + } + + ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen); + if (ndopts->nd_opts_search > ndopts->nd_opts_last) { + /* option overruns the end of buffer, invalid */ + bzero(ndopts, sizeof(*ndopts)); + return NULL; + } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { + /* reached the end of options chain */ + ndopts->nd_opts_done = 1; + ndopts->nd_opts_search = NULL; + } + return nd_opt; +} + +/* + * Parse multiple ND options. + * This function is much easier to use, for ND routines that do not need + * multiple options of the same type. + */ +int +nd6_options(union nd_opts *ndopts) +{ + struct nd_opt_hdr *nd_opt; + int i = 0; + + if (ndopts == NULL) + panic("ndopts == NULL in nd6_options"); + if (ndopts->nd_opts_last == NULL) + panic("uninitialized ndopts in nd6_options"); + if (ndopts->nd_opts_search == NULL) + return 0; + + while (1) { + nd_opt = nd6_option(ndopts); + if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { + /* + * Message validation requires that all included + * options have a length that is greater than zero. + */ + ICMP6STAT_INC(icp6s_nd_badopt); + bzero(ndopts, sizeof(*ndopts)); + return -1; + } + + if (nd_opt == NULL) + goto skip1; + + switch (nd_opt->nd_opt_type) { + case ND_OPT_SOURCE_LINKADDR: + case ND_OPT_TARGET_LINKADDR: + case ND_OPT_MTU: + case ND_OPT_REDIRECTED_HEADER: + if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { + nd6log((LOG_INFO, + "duplicated ND6 option found (type=%d)\n", + nd_opt->nd_opt_type)); + /* XXX bark? */ + } else { + ndopts->nd_opt_array[nd_opt->nd_opt_type] + = nd_opt; + } + break; + case ND_OPT_PREFIX_INFORMATION: + if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { + ndopts->nd_opt_array[nd_opt->nd_opt_type] + = nd_opt; + } + ndopts->nd_opts_pi_end = + (struct nd_opt_prefix_info *)nd_opt; + break; + default: + /* + * Unknown options must be silently ignored, + * to accomodate future extension to the protocol. + */ + nd6log((LOG_DEBUG, + "nd6_options: unsupported option %d - " + "option ignored\n", nd_opt->nd_opt_type)); + } + +skip1: + i++; + if (i > V_nd6_maxndopt) { + ICMP6STAT_INC(icp6s_nd_toomanyopt); + nd6log((LOG_INFO, "too many loop in nd opt\n")); + break; + } + + if (ndopts->nd_opts_done) + break; + } + + return 0; +} + +/* + * ND6 timer routine to handle ND6 entries + */ +void +nd6_llinfo_settimer_locked(struct llentry *ln, long tick) +{ + int canceled; + + LLE_WLOCK_ASSERT(ln); + + if (tick < 0) { + ln->la_expire = 0; + ln->ln_ntick = 0; + canceled = callout_stop(&ln->ln_timer_ch); + } else { + ln->la_expire = time_second + tick / hz; + LLE_ADDREF(ln); + if (tick > INT_MAX) { + ln->ln_ntick = tick - INT_MAX; + canceled = callout_reset(&ln->ln_timer_ch, INT_MAX, + nd6_llinfo_timer, ln); + } else { + ln->ln_ntick = 0; + canceled = callout_reset(&ln->ln_timer_ch, tick, + nd6_llinfo_timer, ln); + } + } + if (canceled) + LLE_REMREF(ln); +} + +void +nd6_llinfo_settimer(struct llentry *ln, long tick) +{ + + LLE_WLOCK(ln); + nd6_llinfo_settimer_locked(ln, tick); + LLE_WUNLOCK(ln); +} + +static void +nd6_llinfo_timer(void *arg) +{ + struct llentry *ln; + struct in6_addr *dst; + struct ifnet *ifp; + struct nd_ifinfo *ndi = NULL; + + KASSERT(arg != NULL, ("%s: arg NULL", __func__)); + ln = (struct llentry *)arg; + LLE_WLOCK_ASSERT(ln); + ifp = ln->lle_tbl->llt_ifp; + + CURVNET_SET(ifp->if_vnet); + + if (ln->ln_ntick > 0) { + if (ln->ln_ntick > INT_MAX) { + ln->ln_ntick -= INT_MAX; + nd6_llinfo_settimer_locked(ln, INT_MAX); + } else { + ln->ln_ntick = 0; + nd6_llinfo_settimer_locked(ln, ln->ln_ntick); + } + goto done; + } + + ndi = ND_IFINFO(ifp); + dst = &L3_ADDR_SIN6(ln)->sin6_addr; + if (ln->la_flags & LLE_STATIC) { + goto done; + } + + if (ln->la_flags & LLE_DELETED) { + (void)nd6_free(ln, 0); + ln = NULL; + goto done; + } + + switch (ln->ln_state) { + case ND6_LLINFO_INCOMPLETE: + if (ln->la_asked < V_nd6_mmaxtries) { + ln->la_asked++; + nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000); + LLE_WUNLOCK(ln); + nd6_ns_output(ifp, NULL, dst, ln, 0); + LLE_WLOCK(ln); + } else { + struct mbuf *m = ln->la_hold; + if (m) { + struct mbuf *m0; + + /* + * assuming every packet in la_hold has the + * same IP header. Send error after unlock. + */ + m0 = m->m_nextpkt; + m->m_nextpkt = NULL; + ln->la_hold = m0; + clear_llinfo_pqueue(ln); + } + (void)nd6_free(ln, 0); + ln = NULL; + if (m != NULL) + icmp6_error2(m, ICMP6_DST_UNREACH, + ICMP6_DST_UNREACH_ADDR, 0, ifp); + } + break; + case ND6_LLINFO_REACHABLE: + if (!ND6_LLINFO_PERMANENT(ln)) { + ln->ln_state = ND6_LLINFO_STALE; + nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); + } + break; + + case ND6_LLINFO_STALE: + /* Garbage Collection(RFC 2461 5.3) */ + if (!ND6_LLINFO_PERMANENT(ln)) { + (void)nd6_free(ln, 1); + ln = NULL; + } + break; + + case ND6_LLINFO_DELAY: + if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { + /* We need NUD */ + ln->la_asked = 1; + ln->ln_state = ND6_LLINFO_PROBE; + nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000); + LLE_WUNLOCK(ln); + nd6_ns_output(ifp, dst, dst, ln, 0); + LLE_WLOCK(ln); + } else { + ln->ln_state = ND6_LLINFO_STALE; /* XXX */ + nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); + } + break; + case ND6_LLINFO_PROBE: + if (ln->la_asked < V_nd6_umaxtries) { + ln->la_asked++; + nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000); + LLE_WUNLOCK(ln); + nd6_ns_output(ifp, dst, dst, ln, 0); + LLE_WLOCK(ln); + } else { + (void)nd6_free(ln, 0); + ln = NULL; + } + break; + default: + panic("%s: paths in a dark night can be confusing: %d", + __func__, ln->ln_state); + } +done: + if (ln != NULL) + LLE_FREE_LOCKED(ln); + CURVNET_RESTORE(); +} + + +/* + * ND6 timer routine to expire default route list and prefix list + */ +void +nd6_timer(void *arg) +{ + CURVNET_SET((struct vnet *) arg); + int s; + struct nd_defrouter *dr; + struct nd_prefix *pr; + struct in6_ifaddr *ia6, *nia6; + struct in6_addrlifetime *lt6; + + callout_reset(&V_nd6_timer_ch, V_nd6_prune * hz, + nd6_timer, curvnet); + + /* expire default router list */ + s = splnet(); + dr = TAILQ_FIRST(&V_nd_defrouter); + while (dr) { + if (dr->expire && dr->expire < time_second) { + struct nd_defrouter *t; + t = TAILQ_NEXT(dr, dr_entry); + defrtrlist_del(dr); + dr = t; + } else { + dr = TAILQ_NEXT(dr, dr_entry); + } + } + + /* + * expire interface addresses. + * in the past the loop was inside prefix expiry processing. + * However, from a stricter speci-confrmance standpoint, we should + * rather separate address lifetimes and prefix lifetimes. + * + * XXXRW: in6_ifaddrhead locking. + */ + addrloop: + TAILQ_FOREACH_SAFE(ia6, &V_in6_ifaddrhead, ia_link, nia6) { + /* check address lifetime */ + lt6 = &ia6->ia6_lifetime; + if (IFA6_IS_INVALID(ia6)) { + int regen = 0; + + /* + * If the expiring address is temporary, try + * regenerating a new one. This would be useful when + * we suspended a laptop PC, then turned it on after a + * period that could invalidate all temporary + * addresses. Although we may have to restart the + * loop (see below), it must be after purging the + * address. Otherwise, we'd see an infinite loop of + * regeneration. + */ + if (V_ip6_use_tempaddr && + (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { + if (regen_tmpaddr(ia6) == 0) + regen = 1; + } + + in6_purgeaddr(&ia6->ia_ifa); + + if (regen) + goto addrloop; /* XXX: see below */ + } else if (IFA6_IS_DEPRECATED(ia6)) { + int oldflags = ia6->ia6_flags; + + ia6->ia6_flags |= IN6_IFF_DEPRECATED; + + /* + * If a temporary address has just become deprecated, + * regenerate a new one if possible. + */ + if (V_ip6_use_tempaddr && + (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && + (oldflags & IN6_IFF_DEPRECATED) == 0) { + + if (regen_tmpaddr(ia6) == 0) { + /* + * A new temporary address is + * generated. + * XXX: this means the address chain + * has changed while we are still in + * the loop. Although the change + * would not cause disaster (because + * it's not a deletion, but an + * addition,) we'd rather restart the + * loop just for safety. Or does this + * significantly reduce performance?? + */ + goto addrloop; + } + } + } else { + /* + * A new RA might have made a deprecated address + * preferred. + */ + ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; + } + } + + /* expire prefix list */ + pr = V_nd_prefix.lh_first; + while (pr) { + /* + * check prefix lifetime. + * since pltime is just for autoconf, pltime processing for + * prefix is not necessary. + */ + if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME && + time_second - pr->ndpr_lastupdate > pr->ndpr_vltime) { + struct nd_prefix *t; + t = pr->ndpr_next; + + /* + * address expiration and prefix expiration are + * separate. NEVER perform in6_purgeaddr here. + */ + + prelist_remove(pr); + pr = t; + } else + pr = pr->ndpr_next; + } + splx(s); + CURVNET_RESTORE(); +} + +/* + * ia6 - deprecated/invalidated temporary address + */ +static int +regen_tmpaddr(struct in6_ifaddr *ia6) +{ + struct ifaddr *ifa; + struct ifnet *ifp; + struct in6_ifaddr *public_ifa6 = NULL; + + ifp = ia6->ia_ifa.ifa_ifp; + IF_ADDR_LOCK(ifp); + TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { + struct in6_ifaddr *it6; + + if (ifa->ifa_addr->sa_family != AF_INET6) + continue; + + it6 = (struct in6_ifaddr *)ifa; + + /* ignore no autoconf addresses. */ + if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) + continue; + + /* ignore autoconf addresses with different prefixes. */ + if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) + continue; + + /* + * Now we are looking at an autoconf address with the same + * prefix as ours. If the address is temporary and is still + * preferred, do not create another one. It would be rare, but + * could happen, for example, when we resume a laptop PC after + * a long period. + */ + if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && + !IFA6_IS_DEPRECATED(it6)) { + public_ifa6 = NULL; + break; + } + + /* + * This is a public autoconf address that has the same prefix + * as ours. If it is preferred, keep it. We can't break the + * loop here, because there may be a still-preferred temporary + * address with the prefix. + */ + if (!IFA6_IS_DEPRECATED(it6)) + public_ifa6 = it6; + + if (public_ifa6 != NULL) + ifa_ref(&public_ifa6->ia_ifa); + } + IF_ADDR_UNLOCK(ifp); + + if (public_ifa6 != NULL) { + int e; + + if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { + ifa_free(&public_ifa6->ia_ifa); + log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" + " tmp addr,errno=%d\n", e); + return (-1); + } + ifa_free(&public_ifa6->ia_ifa); + return (0); + } + + return (-1); +} + +/* + * Nuke neighbor cache/prefix/default router management table, right before + * ifp goes away. + */ +void +nd6_purge(struct ifnet *ifp) +{ + struct nd_defrouter *dr, *ndr; + struct nd_prefix *pr, *npr; + + /* + * Nuke default router list entries toward ifp. + * We defer removal of default router list entries that is installed + * in the routing table, in order to keep additional side effects as + * small as possible. + */ + for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; dr = ndr) { + ndr = TAILQ_NEXT(dr, dr_entry); + if (dr->installed) + continue; + + if (dr->ifp == ifp) + defrtrlist_del(dr); + } + + for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; dr = ndr) { + ndr = TAILQ_NEXT(dr, dr_entry); + if (!dr->installed) + continue; + + if (dr->ifp == ifp) + defrtrlist_del(dr); + } + + /* Nuke prefix list entries toward ifp */ + for (pr = V_nd_prefix.lh_first; pr; pr = npr) { + npr = pr->ndpr_next; + if (pr->ndpr_ifp == ifp) { + /* + * Because if_detach() does *not* release prefixes + * while purging addresses the reference count will + * still be above zero. We therefore reset it to + * make sure that the prefix really gets purged. + */ + pr->ndpr_refcnt = 0; + + /* + * Previously, pr->ndpr_addr is removed as well, + * but I strongly believe we don't have to do it. + * nd6_purge() is only called from in6_ifdetach(), + * which removes all the associated interface addresses + * by itself. + * (jinmei@kame.net 20010129) + */ + prelist_remove(pr); + } + } + + /* cancel default outgoing interface setting */ + if (V_nd6_defifindex == ifp->if_index) + nd6_setdefaultiface(0); + + if (!V_ip6_forwarding && V_ip6_accept_rtadv) { /* XXX: too restrictive? */ + /* refresh default router list + * + * + */ + defrouter_select(); + + } + + /* XXXXX + * We do not nuke the neighbor cache entries here any more + * because the neighbor cache is kept in if_afdata[AF_INET6]. + * nd6_purge() is invoked by in6_ifdetach() which is called + * from if_detach() where everything gets purged. So let + * in6_domifdetach() do the actual L2 table purging work. + */ +} + +/* + * the caller acquires and releases the lock on the lltbls + * Returns the llentry locked + */ +struct llentry * +nd6_lookup(struct in6_addr *addr6, int flags, struct ifnet *ifp) +{ + struct sockaddr_in6 sin6; + struct llentry *ln; + int llflags; + + bzero(&sin6, sizeof(sin6)); + sin6.sin6_len = sizeof(struct sockaddr_in6); + sin6.sin6_family = AF_INET6; + sin6.sin6_addr = *addr6; + + IF_AFDATA_LOCK_ASSERT(ifp); + + llflags = 0; + if (flags & ND6_CREATE) + llflags |= LLE_CREATE; + if (flags & ND6_EXCLUSIVE) + llflags |= LLE_EXCLUSIVE; + + ln = lla_lookup(LLTABLE6(ifp), llflags, (struct sockaddr *)&sin6); + if ((ln != NULL) && (llflags & LLE_CREATE)) + ln->ln_state = ND6_LLINFO_NOSTATE; + + return (ln); +} + +/* + * Test whether a given IPv6 address is a neighbor or not, ignoring + * the actual neighbor cache. The neighbor cache is ignored in order + * to not reenter the routing code from within itself. + */ +static int +nd6_is_new_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp) +{ + struct nd_prefix *pr; + struct ifaddr *dstaddr; + + /* + * A link-local address is always a neighbor. + * XXX: a link does not necessarily specify a single interface. + */ + if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { + struct sockaddr_in6 sin6_copy; + u_int32_t zone; + + /* + * We need sin6_copy since sa6_recoverscope() may modify the + * content (XXX). + */ + sin6_copy = *addr; + if (sa6_recoverscope(&sin6_copy)) + return (0); /* XXX: should be impossible */ + if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) + return (0); + if (sin6_copy.sin6_scope_id == zone) + return (1); + else + return (0); + } + + /* + * If the address matches one of our addresses, + * it should be a neighbor. + * If the address matches one of our on-link prefixes, it should be a + * neighbor. + */ + for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { + if (pr->ndpr_ifp != ifp) + continue; + + if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) { + struct rtentry *rt; + rt = rtalloc1((struct sockaddr *)&pr->ndpr_prefix, 0, 0); + if (rt == NULL) + continue; + /* + * This is the case where multiple interfaces + * have the same prefix, but only one is installed + * into the routing table and that prefix entry + * is not the one being examined here. In the case + * where RADIX_MPATH is enabled, multiple route + * entries (of the same rt_key value) will be + * installed because the interface addresses all + * differ. + */ + if (!IN6_ARE_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, + &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr)) { + RTFREE_LOCKED(rt); + continue; + } + RTFREE_LOCKED(rt); + } + + if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, + &addr->sin6_addr, &pr->ndpr_mask)) + return (1); + } + + /* + * If the address is assigned on the node of the other side of + * a p2p interface, the address should be a neighbor. + */ + dstaddr = ifa_ifwithdstaddr((struct sockaddr *)addr); + if (dstaddr != NULL) { + if (dstaddr->ifa_ifp == ifp) { + ifa_free(dstaddr); + return (1); + } + ifa_free(dstaddr); + } + + /* + * If the default router list is empty, all addresses are regarded + * as on-link, and thus, as a neighbor. + * XXX: we restrict the condition to hosts, because routers usually do + * not have the "default router list". + */ + if (!V_ip6_forwarding && TAILQ_FIRST(&V_nd_defrouter) == NULL && + V_nd6_defifindex == ifp->if_index) { + return (1); + } + + return (0); +} + + +/* + * Detect if a given IPv6 address identifies a neighbor on a given link. + * XXX: should take care of the destination of a p2p link? + */ +int +nd6_is_addr_neighbor(struct sockaddr_in6 *addr, struct ifnet *ifp) +{ + struct llentry *lle; + int rc = 0; + + IF_AFDATA_UNLOCK_ASSERT(ifp); + if (nd6_is_new_addr_neighbor(addr, ifp)) + return (1); + + /* + * Even if the address matches none of our addresses, it might be + * in the neighbor cache. + */ + IF_AFDATA_LOCK(ifp); + if ((lle = nd6_lookup(&addr->sin6_addr, 0, ifp)) != NULL) { + LLE_RUNLOCK(lle); + rc = 1; + } + IF_AFDATA_UNLOCK(ifp); + return (rc); +} + +/* + * Free an nd6 llinfo entry. + * Since the function would cause significant changes in the kernel, DO NOT + * make it global, unless you have a strong reason for the change, and are sure + * that the change is safe. + */ +static struct llentry * +nd6_free(struct llentry *ln, int gc) +{ + struct llentry *next; + struct nd_defrouter *dr; + struct ifnet *ifp; + + LLE_WLOCK_ASSERT(ln); + + /* + * we used to have pfctlinput(PRC_HOSTDEAD) here. + * even though it is not harmful, it was not really necessary. + */ + + /* cancel timer */ + nd6_llinfo_settimer_locked(ln, -1); + + ifp = ln->lle_tbl->llt_ifp; + + if (!V_ip6_forwarding) { + + dr = defrouter_lookup(&L3_ADDR_SIN6(ln)->sin6_addr, ifp); + + if (dr != NULL && dr->expire && + ln->ln_state == ND6_LLINFO_STALE && gc) { + /* + * If the reason for the deletion is just garbage + * collection, and the neighbor is an active default + * router, do not delete it. Instead, reset the GC + * timer using the router's lifetime. + * Simply deleting the entry would affect default + * router selection, which is not necessarily a good + * thing, especially when we're using router preference + * values. + * XXX: the check for ln_state would be redundant, + * but we intentionally keep it just in case. + */ + if (dr->expire > time_second) + nd6_llinfo_settimer_locked(ln, + (dr->expire - time_second) * hz); + else + nd6_llinfo_settimer_locked(ln, + (long)V_nd6_gctimer * hz); + + next = LIST_NEXT(ln, lle_next); + LLE_REMREF(ln); + LLE_WUNLOCK(ln); + return (next); + } + + if (dr) { + /* + * Unreachablity of a router might affect the default + * router selection and on-link detection of advertised + * prefixes. + */ + + /* + * Temporarily fake the state to choose a new default + * router and to perform on-link determination of + * prefixes correctly. + * Below the state will be set correctly, + * or the entry itself will be deleted. + */ + ln->ln_state = ND6_LLINFO_INCOMPLETE; + } + + if (ln->ln_router || dr) { + + /* + * We need to unlock to avoid a LOR with rt6_flush() with the + * rnh and for the calls to pfxlist_onlink_check() and + * defrouter_select() in the block further down for calls + * into nd6_lookup(). We still hold a ref. + */ + LLE_WUNLOCK(ln); + + /* + * rt6_flush must be called whether or not the neighbor + * is in the Default Router List. + * See a corresponding comment in nd6_na_input(). + */ + rt6_flush(&L3_ADDR_SIN6(ln)->sin6_addr, ifp); + } + + if (dr) { + /* + * Since defrouter_select() does not affect the + * on-link determination and MIP6 needs the check + * before the default router selection, we perform + * the check now. + */ + pfxlist_onlink_check(); + + /* + * Refresh default router list. + */ + defrouter_select(); + } + + if (ln->ln_router || dr) + LLE_WLOCK(ln); + } + + /* + * Before deleting the entry, remember the next entry as the + * return value. We need this because pfxlist_onlink_check() above + * might have freed other entries (particularly the old next entry) as + * a side effect (XXX). + */ + next = LIST_NEXT(ln, lle_next); + + /* + * Save to unlock. We still hold an extra reference and will not + * free(9) in llentry_free() if someone else holds one as well. + */ + LLE_WUNLOCK(ln); + IF_AFDATA_LOCK(ifp); + LLE_WLOCK(ln); + LLE_REMREF(ln); + llentry_free(ln); + IF_AFDATA_UNLOCK(ifp); + + return (next); +} + +/* + * Upper-layer reachability hint for Neighbor Unreachability Detection. + * + * XXX cost-effective methods? + */ +void +nd6_nud_hint(struct rtentry *rt, struct in6_addr *dst6, int force) +{ + struct llentry *ln; + struct ifnet *ifp; + + if ((dst6 == NULL) || (rt == NULL)) + return; + + ifp = rt->rt_ifp; + IF_AFDATA_LOCK(ifp); + ln = nd6_lookup(dst6, ND6_EXCLUSIVE, NULL); + IF_AFDATA_UNLOCK(ifp); + if (ln == NULL) + return; + + if (ln->ln_state < ND6_LLINFO_REACHABLE) + goto done; + + /* + * if we get upper-layer reachability confirmation many times, + * it is possible we have false information. + */ + if (!force) { + ln->ln_byhint++; + if (ln->ln_byhint > V_nd6_maxnudhint) { + goto done; + } + } + + ln->ln_state = ND6_LLINFO_REACHABLE; + if (!ND6_LLINFO_PERMANENT(ln)) { + nd6_llinfo_settimer_locked(ln, + (long)ND_IFINFO(rt->rt_ifp)->reachable * hz); + } +done: + LLE_WUNLOCK(ln); +} + + +int +nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp) +{ + struct in6_drlist *drl = (struct in6_drlist *)data; + struct in6_oprlist *oprl = (struct in6_oprlist *)data; + struct in6_ndireq *ndi = (struct in6_ndireq *)data; + struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; + struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; + struct nd_defrouter *dr; + struct nd_prefix *pr; + int i = 0, error = 0; + int s; + + switch (cmd) { + case SIOCGDRLST_IN6: + /* + * obsolete API, use sysctl under net.inet6.icmp6 + */ + bzero(drl, sizeof(*drl)); + s = splnet(); + dr = TAILQ_FIRST(&V_nd_defrouter); + while (dr && i < DRLSTSIZ) { + drl->defrouter[i].rtaddr = dr->rtaddr; + in6_clearscope(&drl->defrouter[i].rtaddr); + + drl->defrouter[i].flags = dr->flags; + drl->defrouter[i].rtlifetime = dr->rtlifetime; + drl->defrouter[i].expire = dr->expire; + drl->defrouter[i].if_index = dr->ifp->if_index; + i++; + dr = TAILQ_NEXT(dr, dr_entry); + } + splx(s); + break; + case SIOCGPRLST_IN6: + /* + * obsolete API, use sysctl under net.inet6.icmp6 + * + * XXX the structure in6_prlist was changed in backward- + * incompatible manner. in6_oprlist is used for SIOCGPRLST_IN6, + * in6_prlist is used for nd6_sysctl() - fill_prlist(). + */ + /* + * XXX meaning of fields, especialy "raflags", is very + * differnet between RA prefix list and RR/static prefix list. + * how about separating ioctls into two? + */ + bzero(oprl, sizeof(*oprl)); + s = splnet(); + pr = V_nd_prefix.lh_first; + while (pr && i < PRLSTSIZ) { + struct nd_pfxrouter *pfr; + int j; + + oprl->prefix[i].prefix = pr->ndpr_prefix.sin6_addr; + oprl->prefix[i].raflags = pr->ndpr_raf; + oprl->prefix[i].prefixlen = pr->ndpr_plen; + oprl->prefix[i].vltime = pr->ndpr_vltime; + oprl->prefix[i].pltime = pr->ndpr_pltime; + oprl->prefix[i].if_index = pr->ndpr_ifp->if_index; + if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) + oprl->prefix[i].expire = 0; + else { + time_t maxexpire; + + /* XXX: we assume time_t is signed. */ + maxexpire = (-1) & + ~((time_t)1 << + ((sizeof(maxexpire) * 8) - 1)); + if (pr->ndpr_vltime < + maxexpire - pr->ndpr_lastupdate) { + oprl->prefix[i].expire = + pr->ndpr_lastupdate + + pr->ndpr_vltime; + } else + oprl->prefix[i].expire = maxexpire; + } + + pfr = pr->ndpr_advrtrs.lh_first; + j = 0; + while (pfr) { + if (j < DRLSTSIZ) { +#define RTRADDR oprl->prefix[i].advrtr[j] + RTRADDR = pfr->router->rtaddr; + in6_clearscope(&RTRADDR); +#undef RTRADDR + } + j++; + pfr = pfr->pfr_next; + } + oprl->prefix[i].advrtrs = j; + oprl->prefix[i].origin = PR_ORIG_RA; + + i++; + pr = pr->ndpr_next; + } + splx(s); + + break; + case OSIOCGIFINFO_IN6: +#define ND ndi->ndi + /* XXX: old ndp(8) assumes a positive value for linkmtu. */ + bzero(&ND, sizeof(ND)); + ND.linkmtu = IN6_LINKMTU(ifp); + ND.maxmtu = ND_IFINFO(ifp)->maxmtu; + ND.basereachable = ND_IFINFO(ifp)->basereachable; + ND.reachable = ND_IFINFO(ifp)->reachable; + ND.retrans = ND_IFINFO(ifp)->retrans; + ND.flags = ND_IFINFO(ifp)->flags; + ND.recalctm = ND_IFINFO(ifp)->recalctm; + ND.chlim = ND_IFINFO(ifp)->chlim; + break; + case SIOCGIFINFO_IN6: + ND = *ND_IFINFO(ifp); + break; + case SIOCSIFINFO_IN6: + /* + * used to change host variables from userland. + * intented for a use on router to reflect RA configurations. + */ + /* 0 means 'unspecified' */ + if (ND.linkmtu != 0) { + if (ND.linkmtu < IPV6_MMTU || + ND.linkmtu > IN6_LINKMTU(ifp)) { + error = EINVAL; + break; + } + ND_IFINFO(ifp)->linkmtu = ND.linkmtu; + } + + if (ND.basereachable != 0) { + int obasereachable = ND_IFINFO(ifp)->basereachable; + + ND_IFINFO(ifp)->basereachable = ND.basereachable; + if (ND.basereachable != obasereachable) + ND_IFINFO(ifp)->reachable = + ND_COMPUTE_RTIME(ND.basereachable); + } + if (ND.retrans != 0) + ND_IFINFO(ifp)->retrans = ND.retrans; + if (ND.chlim != 0) + ND_IFINFO(ifp)->chlim = ND.chlim; + /* FALLTHROUGH */ + case SIOCSIFINFO_FLAGS: + ND_IFINFO(ifp)->flags = ND.flags; + break; +#undef ND + case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ + /* sync kernel routing table with the default router list */ + defrouter_reset(); + defrouter_select(); + break; + case SIOCSPFXFLUSH_IN6: + { + /* flush all the prefix advertised by routers */ + struct nd_prefix *pr, *next; + + s = splnet(); + for (pr = V_nd_prefix.lh_first; pr; pr = next) { + struct in6_ifaddr *ia, *ia_next; + + next = pr->ndpr_next; + + if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) + continue; /* XXX */ + + /* do we really have to remove addresses as well? */ + /* XXXRW: in6_ifaddrhead locking. */ + TAILQ_FOREACH_SAFE(ia, &V_in6_ifaddrhead, ia_link, + ia_next) { + if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) + continue; + + if (ia->ia6_ndpr == pr) + in6_purgeaddr(&ia->ia_ifa); + } + prelist_remove(pr); + } + splx(s); + break; + } + case SIOCSRTRFLUSH_IN6: + { + /* flush all the default routers */ + struct nd_defrouter *dr, *next; + + s = splnet(); + defrouter_reset(); + for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; dr = next) { + next = TAILQ_NEXT(dr, dr_entry); + defrtrlist_del(dr); + } + defrouter_select(); + splx(s); + break; + } + case SIOCGNBRINFO_IN6: + { + struct llentry *ln; + struct in6_addr nb_addr = nbi->addr; /* make local for safety */ + + if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) + return (error); + + IF_AFDATA_LOCK(ifp); + ln = nd6_lookup(&nb_addr, 0, ifp); + IF_AFDATA_UNLOCK(ifp); + + if (ln == NULL) { + error = EINVAL; + break; + } + nbi->state = ln->ln_state; + nbi->asked = ln->la_asked; + nbi->isrouter = ln->ln_router; + nbi->expire = ln->la_expire; + LLE_RUNLOCK(ln); + break; + } + case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ + ndif->ifindex = V_nd6_defifindex; + break; + case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ + return (nd6_setdefaultiface(ndif->ifindex)); + } + return (error); +} + +/* + * Create neighbor cache entry and cache link-layer address, + * on reception of inbound ND6 packets. (RS/RA/NS/redirect) + * + * type - ICMP6 type + * code - type dependent information + * + * XXXXX + * The caller of this function already acquired the ndp + * cache table lock because the cache entry is returned. + */ +struct llentry * +nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr, + int lladdrlen, int type, int code) +{ + struct llentry *ln = NULL; + int is_newentry; + int do_update; + int olladdr; + int llchange; + int flags; + int newstate = 0; + uint16_t router = 0; + struct sockaddr_in6 sin6; + struct mbuf *chain = NULL; + int static_route = 0; + + IF_AFDATA_UNLOCK_ASSERT(ifp); + + if (ifp == NULL) + panic("ifp == NULL in nd6_cache_lladdr"); + if (from == NULL) + panic("from == NULL in nd6_cache_lladdr"); + + /* nothing must be updated for unspecified address */ + if (IN6_IS_ADDR_UNSPECIFIED(from)) + return NULL; + + /* + * Validation about ifp->if_addrlen and lladdrlen must be done in + * the caller. + * + * XXX If the link does not have link-layer adderss, what should + * we do? (ifp->if_addrlen == 0) + * Spec says nothing in sections for RA, RS and NA. There's small + * description on it in NS section (RFC 2461 7.2.3). + */ + flags = lladdr ? ND6_EXCLUSIVE : 0; + IF_AFDATA_LOCK(ifp); + ln = nd6_lookup(from, flags, ifp); + + if (ln == NULL) { + flags |= ND6_EXCLUSIVE; + ln = nd6_lookup(from, flags | ND6_CREATE, ifp); + IF_AFDATA_UNLOCK(ifp); + is_newentry = 1; + } else { + IF_AFDATA_UNLOCK(ifp); + /* do nothing if static ndp is set */ + if (ln->la_flags & LLE_STATIC) { + static_route = 1; + goto done; + } + is_newentry = 0; + } + if (ln == NULL) + return (NULL); + + olladdr = (ln->la_flags & LLE_VALID) ? 1 : 0; + if (olladdr && lladdr) { + llchange = bcmp(lladdr, &ln->ll_addr, + ifp->if_addrlen); + } else + llchange = 0; + + /* + * newentry olladdr lladdr llchange (*=record) + * 0 n n -- (1) + * 0 y n -- (2) + * 0 n y -- (3) * STALE + * 0 y y n (4) * + * 0 y y y (5) * STALE + * 1 -- n -- (6) NOSTATE(= PASSIVE) + * 1 -- y -- (7) * STALE + */ + + if (lladdr) { /* (3-5) and (7) */ + /* + * Record source link-layer address + * XXX is it dependent to ifp->if_type? + */ + bcopy(lladdr, &ln->ll_addr, ifp->if_addrlen); + ln->la_flags |= LLE_VALID; + } + + if (!is_newentry) { + if ((!olladdr && lladdr != NULL) || /* (3) */ + (olladdr && lladdr != NULL && llchange)) { /* (5) */ + do_update = 1; + newstate = ND6_LLINFO_STALE; + } else /* (1-2,4) */ + do_update = 0; + } else { + do_update = 1; + if (lladdr == NULL) /* (6) */ + newstate = ND6_LLINFO_NOSTATE; + else /* (7) */ + newstate = ND6_LLINFO_STALE; + } + + if (do_update) { + /* + * Update the state of the neighbor cache. + */ + ln->ln_state = newstate; + + if (ln->ln_state == ND6_LLINFO_STALE) { + /* + * XXX: since nd6_output() below will cause + * state tansition to DELAY and reset the timer, + * we must set the timer now, although it is actually + * meaningless. + */ + nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); + + if (ln->la_hold) { + struct mbuf *m_hold, *m_hold_next; + + /* + * reset the la_hold in advance, to explicitly + * prevent a la_hold lookup in nd6_output() + * (wouldn't happen, though...) + */ + for (m_hold = ln->la_hold, ln->la_hold = NULL; + m_hold; m_hold = m_hold_next) { + m_hold_next = m_hold->m_nextpkt; + m_hold->m_nextpkt = NULL; + + /* + * we assume ifp is not a p2p here, so + * just set the 2nd argument as the + * 1st one. + */ + nd6_output_lle(ifp, ifp, m_hold, L3_ADDR_SIN6(ln), NULL, ln, &chain); + } + /* + * If we have mbufs in the chain we need to do + * deferred transmit. Copy the address from the + * llentry before dropping the lock down below. + */ + if (chain != NULL) + memcpy(&sin6, L3_ADDR_SIN6(ln), sizeof(sin6)); + } + } else if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { + /* probe right away */ + nd6_llinfo_settimer_locked((void *)ln, 0); + } + } + + /* + * ICMP6 type dependent behavior. + * + * NS: clear IsRouter if new entry + * RS: clear IsRouter + * RA: set IsRouter if there's lladdr + * redir: clear IsRouter if new entry + * + * RA case, (1): + * The spec says that we must set IsRouter in the following cases: + * - If lladdr exist, set IsRouter. This means (1-5). + * - If it is old entry (!newentry), set IsRouter. This means (7). + * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. + * A quetion arises for (1) case. (1) case has no lladdr in the + * neighbor cache, this is similar to (6). + * This case is rare but we figured that we MUST NOT set IsRouter. + * + * newentry olladdr lladdr llchange NS RS RA redir + * D R + * 0 n n -- (1) c ? s + * 0 y n -- (2) c s s + * 0 n y -- (3) c s s + * 0 y y n (4) c s s + * 0 y y y (5) c s s + * 1 -- n -- (6) c c c s + * 1 -- y -- (7) c c s c s + * + * (c=clear s=set) + */ + switch (type & 0xff) { + case ND_NEIGHBOR_SOLICIT: + /* + * New entry must have is_router flag cleared. + */ + if (is_newentry) /* (6-7) */ + ln->ln_router = 0; + break; + case ND_REDIRECT: + /* + * If the icmp is a redirect to a better router, always set the + * is_router flag. Otherwise, if the entry is newly created, + * clear the flag. [RFC 2461, sec 8.3] + */ + if (code == ND_REDIRECT_ROUTER) + ln->ln_router = 1; + else if (is_newentry) /* (6-7) */ + ln->ln_router = 0; + break; + case ND_ROUTER_SOLICIT: + /* + * is_router flag must always be cleared. + */ + ln->ln_router = 0; + break; + case ND_ROUTER_ADVERT: + /* + * Mark an entry with lladdr as a router. + */ + if ((!is_newentry && (olladdr || lladdr)) || /* (2-5) */ + (is_newentry && lladdr)) { /* (7) */ + ln->ln_router = 1; + } + break; + } + + if (ln != NULL) { + static_route = (ln->la_flags & LLE_STATIC); + router = ln->ln_router; + + if (flags & ND6_EXCLUSIVE) + LLE_WUNLOCK(ln); + else + LLE_RUNLOCK(ln); + if (static_route) + ln = NULL; + } + if (chain) + nd6_output_flush(ifp, ifp, chain, &sin6, NULL); + + /* + * When the link-layer address of a router changes, select the + * best router again. In particular, when the neighbor entry is newly + * created, it might affect the selection policy. + * Question: can we restrict the first condition to the "is_newentry" + * case? + * XXX: when we hear an RA from a new router with the link-layer + * address option, defrouter_select() is called twice, since + * defrtrlist_update called the function as well. However, I believe + * we can compromise the overhead, since it only happens the first + * time. + * XXX: although defrouter_select() should not have a bad effect + * for those are not autoconfigured hosts, we explicitly avoid such + * cases for safety. + */ + if (do_update && router && !V_ip6_forwarding && V_ip6_accept_rtadv) { + /* + * guaranteed recursion + */ + defrouter_select(); + } + + return (ln); +done: + if (ln != NULL) { + if (flags & ND6_EXCLUSIVE) + LLE_WUNLOCK(ln); + else + LLE_RUNLOCK(ln); + if (static_route) + ln = NULL; + } + return (ln); +} + +static void +nd6_slowtimo(void *arg) +{ + CURVNET_SET((struct vnet *) arg); + struct nd_ifinfo *nd6if; + struct ifnet *ifp; + + callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, + nd6_slowtimo, curvnet); + IFNET_RLOCK_NOSLEEP(); + for (ifp = TAILQ_FIRST(&V_ifnet); ifp; + ifp = TAILQ_NEXT(ifp, if_list)) { + nd6if = ND_IFINFO(ifp); + if (nd6if->basereachable && /* already initialized */ + (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { + /* + * Since reachable time rarely changes by router + * advertisements, we SHOULD insure that a new random + * value gets recomputed at least once every few hours. + * (RFC 2461, 6.3.4) + */ + nd6if->recalctm = V_nd6_recalc_reachtm_interval; + nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); + } + } + IFNET_RUNLOCK_NOSLEEP(); + CURVNET_RESTORE(); +} + +int +nd6_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m0, + struct sockaddr_in6 *dst, struct rtentry *rt0) +{ + + return (nd6_output_lle(ifp, origifp, m0, dst, rt0, NULL, NULL)); +} + + +/* + * Note that I'm not enforcing any global serialization + * lle state or asked changes here as the logic is too + * complicated to avoid having to always acquire an exclusive + * lock + * KMM + * + */ +#define senderr(e) { error = (e); goto bad;} + +int +nd6_output_lle(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m0, + struct sockaddr_in6 *dst, struct rtentry *rt0, struct llentry *lle, + struct mbuf **chain) +{ + struct mbuf *m = m0; + struct llentry *ln = lle; + int error = 0; + int flags = 0; + +#ifdef INVARIANTS + if (lle != NULL) { + + LLE_WLOCK_ASSERT(lle); + + KASSERT(chain != NULL, (" lle locked but no mbuf chain pointer passed")); + } +#endif + if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr)) + goto sendpkt; + + if (nd6_need_cache(ifp) == 0) + goto sendpkt; + + /* + * next hop determination. This routine is derived from ether_output. + */ + + /* + * Address resolution or Neighbor Unreachability Detection + * for the next hop. + * At this point, the destination of the packet must be a unicast + * or an anycast address(i.e. not a multicast). + */ + + flags = ((m != NULL) || (lle != NULL)) ? LLE_EXCLUSIVE : 0; + if (ln == NULL) { + retry: + IF_AFDATA_LOCK(ifp); + ln = lla_lookup(LLTABLE6(ifp), flags, (struct sockaddr *)dst); + IF_AFDATA_UNLOCK(ifp); + if ((ln == NULL) && nd6_is_addr_neighbor(dst, ifp)) { + /* + * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), + * the condition below is not very efficient. But we believe + * it is tolerable, because this should be a rare case. + */ + flags = ND6_CREATE | (m ? ND6_EXCLUSIVE : 0); + IF_AFDATA_LOCK(ifp); + ln = nd6_lookup(&dst->sin6_addr, flags, ifp); + IF_AFDATA_UNLOCK(ifp); + } + } + if (ln == NULL) { + if ((ifp->if_flags & IFF_POINTOPOINT) == 0 && + !(ND_IFINFO(ifp)->flags & ND6_IFF_PERFORMNUD)) { + char ip6buf[INET6_ADDRSTRLEN]; + log(LOG_DEBUG, + "nd6_output: can't allocate llinfo for %s " + "(ln=%p)\n", + ip6_sprintf(ip6buf, &dst->sin6_addr), ln); + senderr(EIO); /* XXX: good error? */ + } + goto sendpkt; /* send anyway */ + } + + /* We don't have to do link-layer address resolution on a p2p link. */ + if ((ifp->if_flags & IFF_POINTOPOINT) != 0 && + ln->ln_state < ND6_LLINFO_REACHABLE) { + if ((flags & LLE_EXCLUSIVE) == 0) { + flags |= LLE_EXCLUSIVE; + goto retry; + } + ln->ln_state = ND6_LLINFO_STALE; + nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); + } + + /* + * The first time we send a packet to a neighbor whose entry is + * STALE, we have to change the state to DELAY and a sets a timer to + * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do + * neighbor unreachability detection on expiration. + * (RFC 2461 7.3.3) + */ + if (ln->ln_state == ND6_LLINFO_STALE) { + if ((flags & LLE_EXCLUSIVE) == 0) { + flags |= LLE_EXCLUSIVE; + LLE_RUNLOCK(ln); + goto retry; + } + ln->la_asked = 0; + ln->ln_state = ND6_LLINFO_DELAY; + nd6_llinfo_settimer_locked(ln, (long)V_nd6_delay * hz); + } + + /* + * If the neighbor cache entry has a state other than INCOMPLETE + * (i.e. its link-layer address is already resolved), just + * send the packet. + */ + if (ln->ln_state > ND6_LLINFO_INCOMPLETE) + goto sendpkt; + + /* + * There is a neighbor cache entry, but no ethernet address + * response yet. Append this latest packet to the end of the + * packet queue in the mbuf, unless the number of the packet + * does not exceed nd6_maxqueuelen. When it exceeds nd6_maxqueuelen, + * the oldest packet in the queue will be removed. + */ + if (ln->ln_state == ND6_LLINFO_NOSTATE) + ln->ln_state = ND6_LLINFO_INCOMPLETE; + + if ((flags & LLE_EXCLUSIVE) == 0) { + flags |= LLE_EXCLUSIVE; + LLE_RUNLOCK(ln); + goto retry; + } + + LLE_WLOCK_ASSERT(ln); + + if (ln->la_hold) { + struct mbuf *m_hold; + int i; + + i = 0; + for (m_hold = ln->la_hold; m_hold; m_hold = m_hold->m_nextpkt) { + i++; + if (m_hold->m_nextpkt == NULL) { + m_hold->m_nextpkt = m; + break; + } + } + while (i >= V_nd6_maxqueuelen) { + m_hold = ln->la_hold; + ln->la_hold = ln->la_hold->m_nextpkt; + m_freem(m_hold); + i--; + } + } else { + ln->la_hold = m; + } + + /* + * If there has been no NS for the neighbor after entering the + * INCOMPLETE state, send the first solicitation. + */ + if (!ND6_LLINFO_PERMANENT(ln) && ln->la_asked == 0) { + ln->la_asked++; + + nd6_llinfo_settimer_locked(ln, + (long)ND_IFINFO(ifp)->retrans * hz / 1000); + LLE_WUNLOCK(ln); + nd6_ns_output(ifp, NULL, &dst->sin6_addr, ln, 0); + if (lle != NULL && ln == lle) + LLE_WLOCK(lle); + + } else if (lle == NULL || ln != lle) { + /* + * We did the lookup (no lle arg) so we + * need to do the unlock here. + */ + LLE_WUNLOCK(ln); + } + + return (0); + + sendpkt: + /* discard the packet if IPv6 operation is disabled on the interface */ + if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { + error = ENETDOWN; /* better error? */ + goto bad; + } + /* + * ln is valid and the caller did not pass in + * an llentry + */ + if ((ln != NULL) && (lle == NULL)) { + if (flags & LLE_EXCLUSIVE) + LLE_WUNLOCK(ln); + else + LLE_RUNLOCK(ln); + } + +#ifdef MAC + mac_netinet6_nd6_send(ifp, m); +#endif + /* + * We were passed in a pointer to an lle with the lock held + * this means that we can't call if_output as we will + * recurse on the lle lock - so what we do is we create + * a list of mbufs to send and transmit them in the caller + * after the lock is dropped + */ + if (lle != NULL) { + if (*chain == NULL) + *chain = m; + else { + struct mbuf *m = *chain; + + /* + * append mbuf to end of deferred chain + */ + while (m->m_nextpkt != NULL) + m = m->m_nextpkt; + m->m_nextpkt = m; + } + return (error); + } + if ((ifp->if_flags & IFF_LOOPBACK) != 0) { + return ((*ifp->if_output)(origifp, m, (struct sockaddr *)dst, + NULL)); + } + error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst, NULL); + return (error); + + bad: + /* + * ln is valid and the caller did not pass in + * an llentry + */ + if ((ln != NULL) && (lle == NULL)) { + if (flags & LLE_EXCLUSIVE) + LLE_WUNLOCK(ln); + else + LLE_RUNLOCK(ln); + } + if (m) + m_freem(m); + return (error); +} +#undef senderr + + +int +nd6_output_flush(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *chain, + struct sockaddr_in6 *dst, struct route *ro) +{ + struct mbuf *m, *m_head; + struct ifnet *outifp; + int error = 0; + + m_head = chain; + if ((ifp->if_flags & IFF_LOOPBACK) != 0) + outifp = origifp; + else + outifp = ifp; + + while (m_head) { + m = m_head; + m_head = m_head->m_nextpkt; + error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst, ro); + } + + /* + * XXX + * note that intermediate errors are blindly ignored - but this is + * the same convention as used with nd6_output when called by + * nd6_cache_lladdr + */ + return (error); +} + + +int +nd6_need_cache(struct ifnet *ifp) +{ + /* + * XXX: we currently do not make neighbor cache on any interface + * other than ARCnet, Ethernet, FDDI and GIF. + * + * RFC2893 says: + * - unidirectional tunnels needs no ND + */ + switch (ifp->if_type) { + case IFT_ARCNET: + case IFT_ETHER: + case IFT_FDDI: + case IFT_IEEE1394: +#ifdef IFT_L2VLAN + case IFT_L2VLAN: +#endif +#ifdef IFT_IEEE80211 + case IFT_IEEE80211: +#endif +#ifdef IFT_CARP + case IFT_CARP: +#endif + case IFT_GIF: /* XXX need more cases? */ + case IFT_PPP: + case IFT_TUNNEL: + case IFT_BRIDGE: + case IFT_PROPVIRTUAL: + return (1); + default: + return (0); + } +} + +/* + * the callers of this function need to be re-worked to drop + * the lle lock, drop here for now + */ +int +nd6_storelladdr(struct ifnet *ifp, struct mbuf *m, + struct sockaddr *dst, u_char *desten, struct llentry **lle) +{ + struct llentry *ln; + + *lle = NULL; + IF_AFDATA_UNLOCK_ASSERT(ifp); + if (m->m_flags & M_MCAST) { + int i; + + switch (ifp->if_type) { + case IFT_ETHER: + case IFT_FDDI: +#ifdef IFT_L2VLAN + case IFT_L2VLAN: +#endif +#ifdef IFT_IEEE80211 + case IFT_IEEE80211: +#endif + case IFT_BRIDGE: + case IFT_ISO88025: + ETHER_MAP_IPV6_MULTICAST(&SIN6(dst)->sin6_addr, + desten); + return (0); + case IFT_IEEE1394: + /* + * netbsd can use if_broadcastaddr, but we don't do so + * to reduce # of ifdef. + */ + for (i = 0; i < ifp->if_addrlen; i++) + desten[i] = ~0; + return (0); + case IFT_ARCNET: + *desten = 0; + return (0); + default: + m_freem(m); + return (EAFNOSUPPORT); + } + } + + + /* + * the entry should have been created in nd6_store_lladdr + */ + IF_AFDATA_LOCK(ifp); + ln = lla_lookup(LLTABLE6(ifp), 0, dst); + IF_AFDATA_UNLOCK(ifp); + if ((ln == NULL) || !(ln->la_flags & LLE_VALID)) { + if (ln != NULL) + LLE_RUNLOCK(ln); + /* this could happen, if we could not allocate memory */ + m_freem(m); + return (1); + } + + bcopy(&ln->ll_addr, desten, ifp->if_addrlen); + *lle = ln; + LLE_RUNLOCK(ln); + /* + * A *small* use after free race exists here + */ + return (0); +} + +static void +clear_llinfo_pqueue(struct llentry *ln) +{ + struct mbuf *m_hold, *m_hold_next; + + for (m_hold = ln->la_hold; m_hold; m_hold = m_hold_next) { + m_hold_next = m_hold->m_nextpkt; + m_hold->m_nextpkt = NULL; + m_freem(m_hold); + } + + ln->la_hold = NULL; + return; +} + +static int nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS); +static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS); +#ifdef SYSCTL_DECL +SYSCTL_DECL(_net_inet6_icmp6); +#endif +SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_DRLIST, nd6_drlist, + CTLFLAG_RD, nd6_sysctl_drlist, ""); +SYSCTL_NODE(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist, + CTLFLAG_RD, nd6_sysctl_prlist, ""); +SYSCTL_VNET_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, nd6_maxqueuelen, + CTLFLAG_RW, &VNET_NAME(nd6_maxqueuelen), 1, ""); + +static int +nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS) +{ + int error; + char buf[1024] __aligned(4); + struct in6_defrouter *d, *de; + struct nd_defrouter *dr; + + if (req->newptr) + return EPERM; + error = 0; + + for (dr = TAILQ_FIRST(&V_nd_defrouter); dr; + dr = TAILQ_NEXT(dr, dr_entry)) { + d = (struct in6_defrouter *)buf; + de = (struct in6_defrouter *)(buf + sizeof(buf)); + + if (d + 1 <= de) { + bzero(d, sizeof(*d)); + d->rtaddr.sin6_family = AF_INET6; + d->rtaddr.sin6_len = sizeof(d->rtaddr); + d->rtaddr.sin6_addr = dr->rtaddr; + error = sa6_recoverscope(&d->rtaddr); + if (error != 0) + return (error); + d->flags = dr->flags; + d->rtlifetime = dr->rtlifetime; + d->expire = dr->expire; + d->if_index = dr->ifp->if_index; + } else + panic("buffer too short"); + + error = SYSCTL_OUT(req, buf, sizeof(*d)); + if (error) + break; + } + + return (error); +} + +static int +nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS) +{ + int error; + char buf[1024] __aligned(4); + struct in6_prefix *p, *pe; + struct nd_prefix *pr; + char ip6buf[INET6_ADDRSTRLEN]; + + if (req->newptr) + return EPERM; + error = 0; + + for (pr = V_nd_prefix.lh_first; pr; pr = pr->ndpr_next) { + u_short advrtrs; + size_t advance; + struct sockaddr_in6 *sin6, *s6; + struct nd_pfxrouter *pfr; + + p = (struct in6_prefix *)buf; + pe = (struct in6_prefix *)(buf + sizeof(buf)); + + if (p + 1 <= pe) { + bzero(p, sizeof(*p)); + sin6 = (struct sockaddr_in6 *)(p + 1); + + p->prefix = pr->ndpr_prefix; + if (sa6_recoverscope(&p->prefix)) { + log(LOG_ERR, + "scope error in prefix list (%s)\n", + ip6_sprintf(ip6buf, &p->prefix.sin6_addr)); + /* XXX: press on... */ + } + p->raflags = pr->ndpr_raf; + p->prefixlen = pr->ndpr_plen; + p->vltime = pr->ndpr_vltime; + p->pltime = pr->ndpr_pltime; + p->if_index = pr->ndpr_ifp->if_index; + if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) + p->expire = 0; + else { + time_t maxexpire; + + /* XXX: we assume time_t is signed. */ + maxexpire = (-1) & + ~((time_t)1 << + ((sizeof(maxexpire) * 8) - 1)); + if (pr->ndpr_vltime < + maxexpire - pr->ndpr_lastupdate) { + p->expire = pr->ndpr_lastupdate + + pr->ndpr_vltime; + } else + p->expire = maxexpire; + } + p->refcnt = pr->ndpr_refcnt; + p->flags = pr->ndpr_stateflags; + p->origin = PR_ORIG_RA; + advrtrs = 0; + for (pfr = pr->ndpr_advrtrs.lh_first; pfr; + pfr = pfr->pfr_next) { + if ((void *)&sin6[advrtrs + 1] > (void *)pe) { + advrtrs++; + continue; + } + s6 = &sin6[advrtrs]; + bzero(s6, sizeof(*s6)); + s6->sin6_family = AF_INET6; + s6->sin6_len = sizeof(*sin6); + s6->sin6_addr = pfr->router->rtaddr; + if (sa6_recoverscope(s6)) { + log(LOG_ERR, + "scope error in " + "prefix list (%s)\n", + ip6_sprintf(ip6buf, + &pfr->router->rtaddr)); + } + advrtrs++; + } + p->advrtrs = advrtrs; + } else + panic("buffer too short"); + + advance = sizeof(*p) + sizeof(*sin6) * advrtrs; + error = SYSCTL_OUT(req, buf, advance); + if (error) + break; + } + + return (error); +} -- cgit v1.2.3