/* * Copyright (c) 2000-2022 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. * 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if IPSEC #include #include #endif #include struct dadq; static struct dadq *nd6_dad_find(struct ifaddr *, struct nd_opt_nonce *); void nd6_dad_stoptimer(struct ifaddr *); static void nd6_dad_timer(struct ifaddr *); static void nd6_dad_ns_output(struct dadq *, struct ifaddr *); static void nd6_dad_ns_input(struct ifaddr *, char *, int, struct nd_opt_nonce *); static struct mbuf *nd6_dad_na_input(struct mbuf *, struct ifnet *, struct in6_addr *, caddr_t, int); static void dad_addref(struct dadq *, int); static void dad_remref(struct dadq *); static struct dadq *nd6_dad_attach(struct dadq *, struct ifaddr *); static void nd6_dad_detach(struct dadq *, struct ifaddr *); static void nd6_dad_duplicated(struct ifaddr *); static int dad_maxtry = 15; /* max # of *tries* to transmit DAD packet */ #define DAD_LOCK_ASSERT_HELD(_dp) \ LCK_MTX_ASSERT(&(_dp)->dad_lock, LCK_MTX_ASSERT_OWNED) #define DAD_LOCK_ASSERT_NOTHELD(_dp) \ LCK_MTX_ASSERT(&(_dp)->dad_lock, LCK_MTX_ASSERT_NOTOWNED) #define DAD_LOCK(_dp) \ lck_mtx_lock(&(_dp)->dad_lock) #define DAD_LOCK_SPIN(_dp) \ lck_mtx_lock_spin(&(_dp)->dad_lock) #define DAD_CONVERT_LOCK(_dp) do { \ DAD_LOCK_ASSERT_HELD(_dp); \ lck_mtx_convert_spin(&(_dp)->dad_lock); \ } while (0) #define DAD_UNLOCK(_dp) \ lck_mtx_unlock(&(_dp)->dad_lock) #define DAD_ADDREF(_dp) \ dad_addref(_dp, 0) #define DAD_ADDREF_LOCKED(_dp) \ dad_addref(_dp, 1) #define DAD_REMREF(_dp) \ dad_remref(_dp) static LCK_MTX_DECLARE_ATTR(dad6_mutex, &ip6_mutex_grp, &ip6_mutex_attr); static struct sockaddr_in6 hostrtmask; static int nd6_llreach_base = 30; /* seconds */ SYSCTL_DECL(_net_inet6_icmp6); SYSCTL_INT(_net_inet6_icmp6, OID_AUTO, nd6_llreach_base, CTLFLAG_RW | CTLFLAG_LOCKED, &nd6_llreach_base, 0, "default ND6 link-layer reachability max lifetime (in seconds)"); int dad_enhanced = ND6_DAD_ENHANCED_DEFAULT; SYSCTL_DECL(_net_inet6_ip6); SYSCTL_INT(_net_inet6_ip6, OID_AUTO, dad_enhanced, CTLFLAG_RW | CTLFLAG_LOCKED, &dad_enhanced, 0, "Enable Enhanced DAD, which adds a random nonce to NS messages for DAD."); static uint32_t nd6_dad_nonce_max_count = 3; SYSCTL_UINT(_net_inet6_ip6, OID_AUTO, nd6_dad_nonce_max_count, CTLFLAG_RW | CTLFLAG_LOCKED, &nd6_dad_nonce_max_count, 0, "Number of times to ignore same nonce for DAD"); #if DEBUG || DEVELOPMENT static int ip6_p2p_debug = 0; SYSCTL_INT(_net_inet6_ip6, OID_AUTO, ip6_p2p_debug, CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_p2p_debug, 0, "Enable more instrumentation for IPv6 P2P use-case"); #endif /* * Obtain a link-layer source cache entry for the sender. * * NOTE: This is currently only for ND6/Ethernet. */ void nd6_llreach_alloc(struct rtentry *rt, struct ifnet *ifp, void *addr, unsigned int alen, boolean_t solicited) { struct llinfo_nd6 *ln = rt->rt_llinfo; if (nd6_llreach_base != 0 && (ln->ln_expire != 0 || (ifp->if_eflags & IFEF_IPV6_ND6ALT) != 0) && !(rt->rt_ifp->if_flags & IFF_LOOPBACK) && ifp->if_addrlen == IF_LLREACH_MAXLEN && /* Ethernet */ alen == ifp->if_addrlen) { struct if_llreach *lr; const char *why = NULL, *type = ""; /* Become a regular mutex, just in case */ RT_CONVERT_LOCK(rt); if ((lr = ln->ln_llreach) != NULL) { type = (solicited ? "ND6 advertisement" : "ND6 unsolicited announcement"); /* * If target has changed, create a new record; * otherwise keep existing record. */ IFLR_LOCK(lr); if (bcmp(addr, lr->lr_key.addr, alen) != 0) { IFLR_UNLOCK(lr); /* Purge any link-layer info caching */ VERIFY(rt->rt_llinfo_purge != NULL); rt->rt_llinfo_purge(rt); lr = NULL; why = " for different target HW address; " "using new llreach record"; } else { lr->lr_probes = 0; /* reset probe count */ IFLR_UNLOCK(lr); if (solicited) { why = " for same target HW address; " "keeping existing llreach record"; } } } if (lr == NULL) { lr = ln->ln_llreach = ifnet_llreach_alloc(ifp, ETHERTYPE_IPV6, addr, alen, nd6_llreach_base); if (lr != NULL) { lr->lr_probes = 0; /* reset probe count */ if (why == NULL) { why = "creating new llreach record"; } } } if (nd6_debug && lr != NULL && why != NULL) { char tmp[MAX_IPv6_STR_LEN]; nd6log(debug, "%s: %s%s for %s\n", if_name(ifp), type, why, inet_ntop(AF_INET6, &SIN6(rt_key(rt))->sin6_addr, tmp, sizeof(tmp))); } } } void nd6_llreach_use(struct llinfo_nd6 *ln) { if (ln->ln_llreach != NULL) { ln->ln_lastused = net_uptime(); } } /* * Input a Neighbor Solicitation Message. * * Based on RFC 4861 * Based on RFC 4862 (duplicate address detection) */ void nd6_ns_input( struct mbuf *m, int off, int icmp6len) { struct ifnet *ifp = m->m_pkthdr.rcvif; struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); struct nd_neighbor_solicit *nd_ns = NULL; struct in6_addr saddr6 = ip6->ip6_src; struct in6_addr daddr6 = ip6->ip6_dst; uint32_t saddr_ifscope = IN6_IS_SCOPE_EMBED(&saddr6) ? ip6_input_getsrcifscope(m) : IFSCOPE_NONE; struct in6_addr taddr6 = {}; struct in6_addr myaddr6 = {}; uint32_t myaddr_ifscope = IFSCOPE_NONE; char *lladdr = NULL; struct ifaddr *ifa = NULL; int lladdrlen = 0; int anycast = 0, proxy = 0, dadprogress = 0; int tlladdr = 0; union nd_opts ndopts = {}; struct sockaddr_dl proxydl = {}; boolean_t advrouter = FALSE; boolean_t is_dad_probe = FALSE; int oflgclr = 0; uint32_t taddr_ifscope; /* Expect 32-bit aligned data pointer on strict-align platforms */ MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); IP6_EXTHDR_CHECK(m, off, icmp6len, return ); ip6 = mtod(m, struct ip6_hdr *); nd_ns = (struct nd_neighbor_solicit *)((caddr_t)ip6 + off); m->m_pkthdr.pkt_flags |= PKTF_INET6_RESOLVE; taddr6 = nd_ns->nd_ns_target; if (in6_setscope(&taddr6, ifp, &taddr_ifscope) != 0) { goto bad; } if (ip6->ip6_hlim != IPV6_MAXHLIM) { nd6log(error, "nd6_ns_input: invalid hlim (%d) from %s to %s on %s\n", ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), ip6_sprintf(&ip6->ip6_dst), if_name(ifp)); goto bad; } is_dad_probe = IN6_IS_ADDR_UNSPECIFIED(&saddr6); if (is_dad_probe) { /* dst has to be a solicited node multicast address. */ if (daddr6.s6_addr16[0] == IPV6_ADDR_INT16_MLL && /* don't check ifindex portion */ daddr6.s6_addr32[1] == 0 && daddr6.s6_addr32[2] == IPV6_ADDR_INT32_ONE && daddr6.s6_addr8[12] == 0xff) { ; /* good */ } else { nd6log(info, "nd6_ns_input: bad DAD packet " "(wrong ip6 dst)\n"); goto bad; } } else if (!nd6_onlink_ns_rfc4861) { struct sockaddr_in6 src_sa6; /* * According to recent IETF discussions, it is not a good idea * to accept a NS from an address which would not be deemed * to be a neighbor otherwise. This point is expected to be * clarified in future revisions of the specification. */ SOCKADDR_ZERO(&src_sa6, sizeof(src_sa6)); src_sa6.sin6_family = AF_INET6; src_sa6.sin6_len = sizeof(src_sa6); src_sa6.sin6_addr = saddr6; if (!in6_embedded_scope) { src_sa6.sin6_scope_id = saddr_ifscope; } if (!nd6_is_addr_neighbor(&src_sa6, ifp, 0)) { nd6log(info, "nd6_ns_input: " "NS packet from non-neighbor\n"); goto bad; } } if (IN6_IS_ADDR_MULTICAST(&taddr6)) { nd6log(info, "nd6_ns_input: bad NS target (multicast)\n"); goto bad; } icmp6len -= sizeof(*nd_ns); nd6_option_init(nd_ns + 1, icmp6len, &ndopts); if (nd6_options(&ndopts) < 0) { nd6log(info, "nd6_ns_input: invalid ND option, ignored\n"); /* nd6_options have incremented stats */ goto freeit; } if (ndopts.nd_opts_src_lladdr) { lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1); lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3; } if (is_dad_probe && lladdr) { nd6log(info, "nd6_ns_input: bad DAD packet " "(link-layer address option)\n"); goto bad; } /* * Attaching target link-layer address to the NA? * (RFC 2461 7.2.4) * * NS IP dst is unicast/anycast MUST NOT add * NS IP dst is solicited-node multicast MUST add * * In implementation, we add target link-layer address by default. * We do not add one in MUST NOT cases. */ if (!IN6_IS_ADDR_MULTICAST(&daddr6)) { tlladdr = 0; } else { tlladdr = 1; } /* * Target address (taddr6) must be either: * (1) Valid unicast/anycast address for my receiving interface, * (2) Unicast address for which I'm offering proxy service, or * (3) "tentative" or "optimistic" address [DAD is in progress]. */ /* (1) and (3) check. */ ifa = (struct ifaddr *)in6ifa_ifpwithaddr(ifp, &taddr6); /* (2) check. */ if (ifa == NULL) { struct rtentry *rt; struct sockaddr_in6 tsin6; SOCKADDR_ZERO(&tsin6, sizeof tsin6); tsin6.sin6_len = sizeof(struct sockaddr_in6); tsin6.sin6_family = AF_INET6; tsin6.sin6_addr = taddr6; rt = rtalloc1_scoped(SA(&tsin6), 0, 0, ifp->if_index); if (rt != NULL) { RT_LOCK(rt); if ((rt->rt_flags & RTF_ANNOUNCE) != 0 && rt->rt_gateway->sa_family == AF_LINK) { /* * proxy NDP for single entry */ ifa = (struct ifaddr *)in6ifa_ifpforlinklocal( ifp, IN6_IFF_NOTREADY | IN6_IFF_ANYCAST); if (ifa) { proxy = 1; proxydl = *SDL(rt->rt_gateway); } } RT_UNLOCK(rt); rtfree(rt); } } if (ifa == NULL && ip6_forwarding && nd6_prproxy) { /* * Is the target address part of the prefix that is being * proxied and installed on another interface? */ ifa = (struct ifaddr *)in6ifa_prproxyaddr(&taddr6, taddr_ifscope); } if (ifa == NULL) { /* * We've got an NS packet, and we don't have that address * assigned for us. We MUST silently ignore it on this * interface, c.f. RFC 4861 7.2.3. * * Forwarding associated with NDPRF_PRPROXY may apply. */ if (ip6_forwarding && nd6_prproxy) { nd6_prproxy_ns_input(ifp, &saddr6, lladdr, lladdrlen, &daddr6, &taddr6, (ndopts.nd_opts_nonce == NULL) ? NULL : ndopts.nd_opts_nonce->nd_opt_nonce); } goto freeit; } IFA_LOCK(ifa); myaddr6 = *IFA_IN6(ifa); myaddr_ifscope = IFA_SIN6_SCOPE(ifa); anycast = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST; dadprogress = ((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DADPROGRESS; if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DUPLICATED) { IFA_UNLOCK(ifa); goto freeit; } IFA_UNLOCK(ifa); if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { nd6log(info, "nd6_ns_input: lladdrlen mismatch for %s " "(if %d, NS packet %d)\n", ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2); goto bad; } if (in6_are_addr_equal_scoped(&myaddr6, &saddr6, myaddr_ifscope, saddr_ifscope)) { nd6log(info, "nd6_ns_input: duplicate IP6 address %s\n", ip6_sprintf(&saddr6)); goto freeit; } /* * We have neighbor solicitation packet, with target address equals to * one of my DAD in-progress addresses. * * src addr how to process? * --- --- * multicast of course, invalid (rejected in ip6_input) * unicast somebody is doing address resolution * unspec dup address detection * * The processing is defined in the "draft standard" RFC 4862 (and by * RFC 4429, which is a "proposed standard" update to its obsolete * predecessor, RFC 2462) The reason optimistic DAD is not included * in RFC 4862 is entirely due to IETF procedural considerations. */ if (dadprogress) { /* * If source address is unspecified address, it is for * duplicate address detection. * * If not, the packet is for addess resolution; * silently ignore it when not optimistic * * Per RFC 4429 the reply for an optimistic address must * have the Override flag cleared */ if (!is_dad_probe && (dadprogress & IN6_IFF_OPTIMISTIC) != 0) { oflgclr = 1; } else { if (is_dad_probe) { nd6_dad_ns_input(ifa, lladdr, lladdrlen, ndopts.nd_opts_nonce); } goto freeit; } } /* Are we an advertising router on this interface? */ advrouter = (ifp->if_ipv6_router_mode != IPV6_ROUTER_MODE_DISABLED); /* * If the source address is unspecified address, entries must not * be created or updated. * It looks that sender is performing DAD. If I'm using the address, * and it's a "preferred" address, i.e. not optimistic, then output NA * toward all-node multicast address, to tell the sender that I'm using * the address. * S bit ("solicited") must be zero. */ if (is_dad_probe) { saddr6 = in6addr_linklocal_allnodes; if (in6_setscope(&saddr6, ifp, NULL) != 0) { goto bad; } if ((dadprogress & IN6_IFF_OPTIMISTIC) == 0) { nd6_na_output(ifp, &saddr6, &taddr6, ((anycast || proxy || !tlladdr) ? 0 : ND_NA_FLAG_OVERRIDE) | (advrouter ? ND_NA_FLAG_ROUTER : 0), tlladdr, proxy ? SA(&proxydl) : NULL); } goto freeit; } nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_NEIGHBOR_SOLICIT, 0, NULL); nd6_na_output(ifp, &saddr6, &taddr6, ((anycast || proxy || !tlladdr || oflgclr) ? 0 : ND_NA_FLAG_OVERRIDE) | (advrouter ? ND_NA_FLAG_ROUTER : 0) | ND_NA_FLAG_SOLICITED, tlladdr, proxy ? SA(&proxydl) : NULL); freeit: m_freem(m); if (ifa != NULL) { ifa_remref(ifa); } return; bad: nd6log(error, "nd6_ns_input: src=%s\n", ip6_sprintf(&saddr6)); nd6log(error, "nd6_ns_input: dst=%s\n", ip6_sprintf(&daddr6)); nd6log(error, "nd6_ns_input: tgt=%s\n", ip6_sprintf(&taddr6)); icmp6stat.icp6s_badns++; m_freem(m); if (ifa != NULL) { ifa_remref(ifa); } } /* * Output a Neighbor Solicitation Message. Caller specifies: * - ICMP6 header source IP6 address * - ND6 header target IP6 address * - ND6 header source datalink address * * Based on RFC 4861 * Based on RFC 4862 (duplicate address detection) * Based on RFC 4429 (optimistic duplicate address detection) * * Caller must bump up ln->ln_rt refcnt to make sure 'ln' doesn't go * away if there is a llinfo_nd6 passed in. */ void nd6_ns_output( struct ifnet *ifp, const struct in6_addr *daddr6, const struct in6_addr *taddr6, struct llinfo_nd6 *ln, /* for source address determination */ uint8_t *nonce) /* duplicated address detection */ { struct mbuf *m; struct ip6_hdr *ip6; struct nd_neighbor_solicit *nd_ns; struct in6_ifaddr *ia = NULL; struct in6_addr *src, src_in, src_storage; struct ip6_moptions *im6o = NULL; struct ifnet *outif = NULL; int icmp6len; int maxlen; int flags; caddr_t mac; struct route_in6 ro; struct ip6_out_args ip6oa; u_int32_t rtflags = 0; boolean_t is_optimistic = FALSE; if ((ifp->if_eflags & IFEF_IPV6_ND6ALT) || IN6_IS_ADDR_MULTICAST(taddr6)) { return; } bzero(&ro, sizeof(ro)); bzero(&ip6oa, sizeof(ip6oa)); ip6oa.ip6oa_boundif = ifp->if_index; ip6oa.ip6oa_flags = IP6OAF_SELECT_SRCIF | IP6OAF_BOUND_SRCADDR | IP6OAF_AWDL_UNRESTRICTED | IP6OAF_INTCOPROC_ALLOWED | IP6OAF_MANAGEMENT_ALLOWED; ip6oa.ip6oa_sotc = SO_TC_UNSPEC; ip6oa.ip6oa_netsvctype = _NET_SERVICE_TYPE_UNSPEC; ip6oa.ip6oa_flags |= IP6OAF_BOUND_IF; /* estimate the size of message */ maxlen = sizeof(*ip6) + sizeof(*nd_ns); maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; if (max_linkhdr + maxlen >= MCLBYTES) { #if DIAGNOSTIC printf("nd6_ns_output: max_linkhdr + maxlen >= MCLBYTES " "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); #endif return; } MGETHDR(m, M_DONTWAIT, MT_DATA); /* XXXMAC: mac_create_mbuf_linklayer() probably */ if (m && max_linkhdr + maxlen >= MHLEN) { MCLGET(m, M_DONTWAIT); if ((m->m_flags & M_EXT) == 0) { m_free(m); m = NULL; } } if (m == NULL) { return; } m->m_pkthdr.rcvif = NULL; if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) { m->m_flags |= M_MCAST; im6o = ip6_allocmoptions(Z_NOWAIT); if (im6o == NULL) { m_freem(m); return; } im6o->im6o_multicast_ifp = ifp; im6o->im6o_multicast_hlim = IPV6_MAXHLIM; im6o->im6o_multicast_loop = 0; } icmp6len = sizeof(*nd_ns); m->m_pkthdr.len = m->m_len = sizeof(*ip6) + icmp6len; m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ /* fill neighbor solicitation packet */ ip6 = mtod(m, struct ip6_hdr *); ip6->ip6_flow = 0; ip6->ip6_vfc &= ~IPV6_VERSION_MASK; ip6->ip6_vfc |= IPV6_VERSION; /* ip6->ip6_plen will be set later */ ip6->ip6_nxt = IPPROTO_ICMPV6; ip6->ip6_hlim = IPV6_MAXHLIM; if (daddr6) { ip6->ip6_dst = *daddr6; ip6_output_setdstifscope(m, ifp->if_index, NULL); } else { ip6->ip6_dst.s6_addr16[0] = IPV6_ADDR_INT16_MLL; ip6->ip6_dst.s6_addr16[1] = 0; ip6->ip6_dst.s6_addr32[1] = 0; ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_ONE; ip6->ip6_dst.s6_addr32[3] = taddr6->s6_addr32[3]; ip6->ip6_dst.s6_addr8[12] = 0xff; ip6_output_setdstifscope(m, ifp->if_index, NULL); if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) { goto bad; } } if (nonce == NULL) { /* * RFC2461 7.2.2: * "If the source address of the packet prompting the * solicitation is the same as one of the addresses assigned * to the outgoing interface, that address SHOULD be placed * in the IP Source Address of the outgoing solicitation. * Otherwise, any one of the addresses assigned to the * interface should be used." * * We use the source address for the prompting packet * (saddr6), if: * - saddr6 is given from the caller (by giving "ln"), and * - saddr6 belongs to the outgoing interface. * Otherwise, we perform the source address selection as usual. */ struct ip6_hdr *hip6; /* hold ip6 */ struct in6_addr *hsrc = NULL; /* Caller holds ref on this route */ if (ln != NULL) { RT_LOCK(ln->ln_rt); /* * assuming every packet in ln_hold has the same IP * header */ if (ln->ln_hold != NULL) { hip6 = mtod(ln->ln_hold, struct ip6_hdr *); /* XXX pullup? */ if (sizeof(*hip6) < ln->ln_hold->m_len) { hsrc = &hip6->ip6_src; } else { hsrc = NULL; } } /* Update probe count, if applicable */ if (ln->ln_llreach != NULL) { IFLR_LOCK_SPIN(ln->ln_llreach); ln->ln_llreach->lr_probes++; IFLR_UNLOCK(ln->ln_llreach); } rtflags = ln->ln_rt->rt_flags; RT_UNLOCK(ln->ln_rt); } if (hsrc != NULL && (ia = in6ifa_ifpwithaddr(ifp, hsrc)) && (ia->ia6_flags & IN6_IFF_OPTIMISTIC) == 0) { src = hsrc; } else { int error; struct sockaddr_in6 dst_sa; SOCKADDR_ZERO(&dst_sa, sizeof(dst_sa)); dst_sa.sin6_family = AF_INET6; dst_sa.sin6_len = sizeof(dst_sa); dst_sa.sin6_addr = ip6->ip6_dst; src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &src_storage, ip6oa.ip6oa_boundif, &error); if (src == NULL) { nd6log(debug, "nd6_ns_output: source can't be " "determined: dst=%s, error=%d\n", ip6_sprintf(&dst_sa.sin6_addr), error); goto bad; } if (ia != NULL) { ifa_remref(&ia->ia_ifa); ia = NULL; } /* * RFC 4429 section 3.2: * When a node has a unicast packet to send * from an Optimistic Address to a neighbor, * but does not know the neighbor's link-layer * address, it MUST NOT perform Address * Resolution. */ ia = in6ifa_ifpwithaddr(ifp, src); if (ia == NULL) { nd6log(debug, "nd6_ns_output: no preferred source " "available: dst=%s\n", ip6_sprintf(&dst_sa.sin6_addr)); goto bad; } if (ia->ia6_flags & IN6_IFF_OPTIMISTIC) { is_optimistic = TRUE; nd6log(debug, "nd6_ns_output: preferred source " "available is optimistic: dst=%s\n", ip6_sprintf(&dst_sa.sin6_addr)); } } } else { /* * Source address for DAD packet must always be IPv6 * unspecified address. (0::0) * We actually don't have to 0-clear the address (we did it * above), but we do so here explicitly to make the intention * clearer. */ bzero(&src_in, sizeof(src_in)); src = &src_in; ip6oa.ip6oa_flags &= ~IP6OAF_BOUND_SRCADDR; } ip6->ip6_src = *src; ip6_output_setsrcifscope(m, ifp->if_index, ia); nd_ns = (struct nd_neighbor_solicit *)(ip6 + 1); nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT; nd_ns->nd_ns_code = 0; nd_ns->nd_ns_reserved = 0; nd_ns->nd_ns_target = *taddr6; in6_clearscope(&nd_ns->nd_ns_target); /* XXX */ /* * Add source link-layer address option. * * spec implementation * --- --- * DAD packet MUST NOT do not add the option * Source is optimistic MUST NOT do not add the option * there's no link layer address: * impossible do not add the option * there's link layer address: * Multicast NS MUST add one add the option * Unicast NS SHOULD add one add the option * * XXX We deviate from RFC 4429 and still use optimistic DAD as source * for address resolution. However to ensure that we do not interfere * with neighbor cache entries of other neighbors, we MUST ensure * that SLLAO is not sent. Also note, sending multicast NS without SLLAO * is also a deviation from RFC 4861. */ if (nonce == NULL && (mac = nd6_ifptomac(ifp)) && !is_optimistic) { int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); /* 8 byte alignments... */ optlen = (optlen + 7) & ~7; m->m_pkthdr.len += optlen; m->m_len += optlen; icmp6len += optlen; bzero((caddr_t)nd_opt, optlen); nd_opt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; nd_opt->nd_opt_len = (uint8_t)(optlen >> 3); bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); } /* * Add a Nonce option (RFC 3971) to detect looped back NS messages. * This behavior is documented as Enhanced Duplicate Address * Detection in draft-ietf-6man-enhanced-dad-13. * net.inet6.ip6.dad_enhanced=0 disables this. */ if (dad_enhanced != 0 && nonce != NULL && !(ifp->if_flags & IFF_POINTOPOINT)) { int optlen = sizeof(struct nd_opt_hdr) + ND_OPT_NONCE_LEN; struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_ns + 1); /* 8-byte alignment is required. */ optlen = (optlen + 7) & ~7; m->m_pkthdr.len += optlen; m->m_len += optlen; icmp6len += optlen; bzero((caddr_t)nd_opt, optlen); nd_opt->nd_opt_type = ND_OPT_NONCE; nd_opt->nd_opt_len = (uint8_t)(optlen >> 3); bcopy(nonce, (caddr_t)(nd_opt + 1), ND_OPT_NONCE_LEN); } ip6->ip6_plen = htons((u_short)icmp6len); nd_ns->nd_ns_cksum = 0; nd_ns->nd_ns_cksum = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), icmp6len); flags = nonce ? IPV6_UNSPECSRC : 0; flags |= IPV6_OUTARGS; /* * PKTF_{INET,INET6}_RESOLVE_RTR are mutually exclusive, so make * sure only one of them is set (just in case.) */ m->m_pkthdr.pkt_flags &= ~(PKTF_INET_RESOLVE | PKTF_RESOLVE_RTR); m->m_pkthdr.pkt_flags |= PKTF_INET6_RESOLVE; /* * If this is a NS for resolving the (default) router, mark * the packet accordingly so that the driver can find out, * in case it needs to perform driver-specific action(s). */ if (rtflags & RTF_ROUTER) { m->m_pkthdr.pkt_flags |= PKTF_RESOLVE_RTR; } if (ifp->if_eflags & IFEF_TXSTART) { /* * Use control service class if the interface * supports transmit-start model */ (void) m_set_service_class(m, MBUF_SC_CTL); } ip6oa.ip6oa_flags |= IP6OAF_SKIP_PF; ip6oa.ip6oa_flags |= IP6OAF_DONT_FRAG; ip6_output(m, NULL, NULL, flags, im6o, &outif, &ip6oa); if (outif) { icmp6_ifstat_inc(outif, ifs6_out_msg); icmp6_ifstat_inc(outif, ifs6_out_neighborsolicit); ifnet_release(outif); } icmp6stat.icp6s_outhist[ND_NEIGHBOR_SOLICIT]++; exit: if (im6o != NULL) { IM6O_REMREF(im6o); } ROUTE_RELEASE(&ro); /* we don't cache this route. */ if (ia != NULL) { ifa_remref(&ia->ia_ifa); } return; bad: m_freem(m); goto exit; } /* * Neighbor advertisement input handling. * * Based on RFC 4861 * Based on RFC 4862 (duplicate address detection) * * the following items are not implemented yet: * - anycast advertisement delay rule (RFC 4861 7.2.7, SHOULD) * - proxy advertisement delay rule (RFC 4861 7.2.8, last paragraph, "should") */ void nd6_na_input(struct mbuf *m, int off, int icmp6len) { struct ifnet *ifp = m->m_pkthdr.rcvif; struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); struct nd_neighbor_advert *nd_na; struct in6_addr saddr6 = ip6->ip6_src; struct in6_addr daddr6 = ip6->ip6_dst; struct in6_addr taddr6; int flags; int is_router; int is_solicited; int is_override; char *lladdr = NULL; int lladdrlen = 0; struct llinfo_nd6 *ln; struct rtentry *rt; struct sockaddr_dl *sdl; union nd_opts ndopts; uint64_t timenow; bool send_nc_alive_kev = false; if ((ifp->if_eflags & IFEF_IPV6_ND6ALT) != 0) { nd6log(info, "nd6_na_input: on ND6ALT interface!\n"); goto freeit; } /* Expect 32-bit aligned data pointer on strict-align platforms */ MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); if (ip6->ip6_hlim != IPV6_MAXHLIM) { nd6log(error, "nd6_na_input: invalid hlim (%d) from %s to %s on %s\n", ip6->ip6_hlim, ip6_sprintf(&ip6->ip6_src), ip6_sprintf(&ip6->ip6_dst), if_name(ifp)); goto bad; } IP6_EXTHDR_CHECK(m, off, icmp6len, return ); ip6 = mtod(m, struct ip6_hdr *); nd_na = (struct nd_neighbor_advert *)((caddr_t)ip6 + off); m->m_pkthdr.pkt_flags |= PKTF_INET6_RESOLVE; flags = nd_na->nd_na_flags_reserved; is_router = ((flags & ND_NA_FLAG_ROUTER) != 0); is_solicited = ((flags & ND_NA_FLAG_SOLICITED) != 0); is_override = ((flags & ND_NA_FLAG_OVERRIDE) != 0); taddr6 = nd_na->nd_na_target; if (in6_setscope(&taddr6, ifp, NULL)) { goto bad; /* XXX: impossible */ } if (IN6_IS_ADDR_MULTICAST(&taddr6)) { nd6log(error, "nd6_na_input: invalid target address %s\n", ip6_sprintf(&taddr6)); goto bad; } if (IN6_IS_ADDR_MULTICAST(&daddr6)) { if (is_solicited) { nd6log(error, "nd6_na_input: a solicited adv is multicasted\n"); goto bad; } } icmp6len -= sizeof(*nd_na); nd6_option_init(nd_na + 1, icmp6len, &ndopts); if (nd6_options(&ndopts) < 0) { nd6log(info, "nd6_na_input: invalid ND option, ignored\n"); /* nd6_options have incremented stats */ goto freeit; } if (ndopts.nd_opts_tgt_lladdr) { lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; if (((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { nd6log(info, "nd6_na_input: lladdrlen mismatch for %s " "(if %d, NA packet %d)\n", ip6_sprintf(&taddr6), ifp->if_addrlen, lladdrlen - 2); goto bad; } } m = nd6_dad_na_input(m, ifp, &taddr6, lladdr, lladdrlen); if (m == NULL) { return; } /* Forwarding associated with NDPRF_PRPROXY may apply. */ if (ip6_forwarding && nd6_prproxy) { nd6_prproxy_na_input(ifp, &saddr6, &daddr6, &taddr6, flags); } /* * If no neighbor cache entry is found, NA SHOULD silently be * discarded. If we are forwarding (and Scoped Routing is in * effect), try to see if there is a neighbor cache entry on * another interface (in case we are doing prefix proxying.) */ if ((rt = nd6_lookup(&taddr6, 0, ifp, 0)) == NULL) { if (!ip6_forwarding || !nd6_prproxy) { goto freeit; } if ((rt = nd6_lookup(&taddr6, 0, NULL, 0)) == NULL) { goto freeit; } RT_LOCK_ASSERT_HELD(rt); if (rt->rt_ifp != ifp) { /* * Purge any link-layer info caching. */ if (rt->rt_llinfo_purge != NULL) { rt->rt_llinfo_purge(rt); } /* Adjust route ref count for the interfaces */ if (rt->rt_if_ref_fn != NULL) { rt->rt_if_ref_fn(ifp, 1); rt->rt_if_ref_fn(rt->rt_ifp, -1); } /* Change the interface when the existing route is on */ rt->rt_ifp = ifp; /* * If rmx_mtu is not locked, update it * to the MTU used by the new interface. */ if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) { rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; } } } RT_LOCK_ASSERT_HELD(rt); if ((ln = rt->rt_llinfo) == NULL || (sdl = SDL(rt->rt_gateway)) == NULL) { RT_REMREF_LOCKED(rt); RT_UNLOCK(rt); goto freeit; } timenow = net_uptime(); if (ln->ln_state == ND6_LLINFO_INCOMPLETE) { /* * If the link-layer has address, and no lladdr option came, * discard the packet. */ if (ifp->if_addrlen && !lladdr) { RT_REMREF_LOCKED(rt); RT_UNLOCK(rt); goto freeit; } /* * Record link-layer address, and update the state. */ sdl->sdl_alen = ifp->if_addrlen; bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); if (is_solicited) { send_nc_alive_kev = (rt->rt_flags & RTF_ROUTER) ? true : false; ND6_CACHE_STATE_TRANSITION(ln, ND6_LLINFO_REACHABLE); if (ln->ln_expire != 0) { struct nd_ifinfo *ndi = NULL; ndi = ND_IFINFO(rt->rt_ifp); VERIFY(ndi != NULL && ndi->initialized); lck_mtx_lock(&ndi->lock); ln_setexpire(ln, timenow + ndi->reachable); lck_mtx_unlock(&ndi->lock); RT_UNLOCK(rt); lck_mtx_lock(rnh_lock); nd6_sched_timeout(NULL, NULL); lck_mtx_unlock(rnh_lock); RT_LOCK(rt); } } else { ND6_CACHE_STATE_TRANSITION(ln, ND6_LLINFO_STALE); ln_setexpire(ln, timenow + nd6_gctimer); } /* * Enqueue work item to invoke callback for this * route entry */ route_event_enqueue_nwk_wq_entry(rt, NULL, ROUTE_LLENTRY_RESOLVED, NULL, TRUE); if ((ln->ln_router = (short)is_router) != 0) { struct radix_node_head *rnh = NULL; struct in6_addr rt_addr = SIN6(rt_key(rt))->sin6_addr; struct ifnet *rt_ifp = rt->rt_ifp; struct route_event rt_ev; route_event_init(&rt_ev, rt, NULL, ROUTE_LLENTRY_RESOLVED); /* * This means a router's state has changed from * non-reachable to probably reachable, and might * affect the status of associated prefixes.. * We already have a reference on rt. Don't need to * take one for the unlock/lock. */ RT_UNLOCK(rt); defrouter_set_reachability(&rt_addr, rt_ifp, TRUE); lck_mtx_lock(rnh_lock); rnh = rt_tables[AF_INET6]; if (rnh != NULL) { (void) rnh->rnh_walktree(rnh, route_event_walktree, (void *)&rt_ev); } lck_mtx_unlock(rnh_lock); lck_mtx_lock(nd6_mutex); pfxlist_onlink_check(); lck_mtx_unlock(nd6_mutex); RT_LOCK(rt); } } else { int llchange = 0; /* * Check if the link-layer address has changed or not. */ if (lladdr == NULL) { llchange = 0; } else { if (sdl->sdl_alen) { if (bcmp(lladdr, LLADDR(sdl), ifp->if_addrlen)) { llchange = 1; } else { llchange = 0; } } else { llchange = 1; } } /* * This is VERY complex. Look at it with care. * * override solicit lladdr llchange action * (L: record lladdr) * * 0 0 n -- (2c) * 0 0 y n (2b) L * 0 0 y y (1) REACHABLE->STALE * 0 1 n -- (2c) *->REACHABLE * 0 1 y n (2b) L *->REACHABLE * 0 1 y y (1) REACHABLE->STALE * 1 0 n -- (2a) * 1 0 y n (2a) L * 1 0 y y (2a) L *->STALE * 1 1 n -- (2a) *->REACHABLE * 1 1 y n (2a) L *->REACHABLE * 1 1 y y (2a) L *->REACHABLE */ if (!is_override && (lladdr != NULL && llchange)) { /* (1) */ /* * If state is REACHABLE, make it STALE. * no other updates should be done. */ if (ln->ln_state == ND6_LLINFO_REACHABLE) { ND6_CACHE_STATE_TRANSITION(ln, ND6_LLINFO_STALE); ln_setexpire(ln, timenow + nd6_gctimer); } RT_REMREF_LOCKED(rt); RT_UNLOCK(rt); goto freeit; } else if (is_override /* (2a) */ || (!is_override && (lladdr && !llchange)) /* (2b) */ || !lladdr) { /* (2c) */ /* * Update link-local address, if any. */ if (lladdr) { sdl->sdl_alen = ifp->if_addrlen; bcopy(lladdr, LLADDR(sdl), ifp->if_addrlen); } /* * If solicited, make the state REACHABLE. * If not solicited and the link-layer address was * changed, make it STALE. */ if (is_solicited) { ND6_CACHE_STATE_TRANSITION(ln, ND6_LLINFO_REACHABLE); if (ln->ln_expire != 0) { struct nd_ifinfo *ndi = NULL; ndi = ND_IFINFO(ifp); VERIFY(ndi != NULL && ndi->initialized); lck_mtx_lock(&ndi->lock); ln_setexpire(ln, timenow + ndi->reachable); lck_mtx_unlock(&ndi->lock); RT_UNLOCK(rt); lck_mtx_lock(rnh_lock); nd6_sched_timeout(NULL, NULL); lck_mtx_unlock(rnh_lock); RT_LOCK(rt); } } else { if (lladdr && llchange) { ND6_CACHE_STATE_TRANSITION(ln, ND6_LLINFO_STALE); ln_setexpire(ln, timenow + nd6_gctimer); } } /* * XXX * The above is somewhat convoluted, for now just * issue a callback for LLENTRY changed. */ /* Enqueue work item to invoke callback for this route entry */ if (llchange) { route_event_enqueue_nwk_wq_entry(rt, NULL, ROUTE_LLENTRY_CHANGED, NULL, TRUE); } /* * If the router's link-layer address has changed, * notify routes using this as gateway so they can * update any cached information. */ if (ln->ln_router && is_router && llchange) { struct radix_node_head *rnh = NULL; struct in6_addr rt_addr = SIN6(rt_key(rt))->sin6_addr; struct ifnet *rt_ifp = rt->rt_ifp; struct route_event rt_ev; route_event_init(&rt_ev, rt, NULL, ROUTE_LLENTRY_CHANGED); /* * This means a router's state has changed from * non-reachable to probably reachable, and might * affect the status of associated prefixes.. * * We already have a valid rt reference here. * We don't need to take another one for unlock/lock. */ RT_UNLOCK(rt); defrouter_set_reachability(&rt_addr, rt_ifp, TRUE); lck_mtx_lock(rnh_lock); rnh = rt_tables[AF_INET6]; if (rnh != NULL) { (void) rnh->rnh_walktree(rnh, route_event_walktree, (void *)&rt_ev); } lck_mtx_unlock(rnh_lock); RT_LOCK(rt); } } if (ln->ln_router && !is_router) { /* * The peer dropped the router flag. * Remove the sender from the Default Router List and * update the Destination Cache entries. */ struct nd_defrouter *dr; struct in6_addr *in6; struct ifnet *rt_ifp = rt->rt_ifp; in6 = &SIN6(rt_key(rt))->sin6_addr; RT_UNLOCK(rt); lck_mtx_lock(nd6_mutex); /* * XXX Handle router lists for route information option * as well. */ dr = defrouter_lookup(NULL, in6, rt_ifp); if (dr) { TAILQ_REMOVE(&nd_defrouter_list, dr, dr_entry); defrtrlist_del(dr, NULL); NDDR_REMREF(dr); /* remove list reference */ NDDR_REMREF(dr); lck_mtx_unlock(nd6_mutex); } else { lck_mtx_unlock(nd6_mutex); /* * Even if the neighbor is not in the * default router list, the neighbor * may be used as a next hop for some * destinations (e.g. redirect case). * So we must call rt6_flush explicitly. */ rt6_flush(&ip6->ip6_src, rt_ifp); } RT_LOCK(rt); } ln->ln_router = (short)is_router; } if (send_nc_alive_kev && (ifp->if_addrlen == IF_LLREACH_MAXLEN)) { struct kev_msg ev_msg; struct kev_nd6_ndalive nd6_ndalive; bzero(&ev_msg, sizeof(ev_msg)); bzero(&nd6_ndalive, sizeof(nd6_ndalive)); ev_msg.vendor_code = KEV_VENDOR_APPLE; ev_msg.kev_class = KEV_NETWORK_CLASS; ev_msg.kev_subclass = KEV_ND6_SUBCLASS; ev_msg.event_code = KEV_ND6_NDALIVE; nd6_ndalive.link_data.if_family = ifp->if_family; nd6_ndalive.link_data.if_unit = ifp->if_unit; strlcpy(nd6_ndalive.link_data.if_name, ifp->if_name, sizeof(nd6_ndalive.link_data.if_name)); ev_msg.dv[0].data_ptr = &nd6_ndalive; ev_msg.dv[0].data_length = sizeof(nd6_ndalive); dlil_post_complete_msg(NULL, &ev_msg); } RT_LOCK_ASSERT_HELD(rt); rt->rt_flags &= ~RTF_REJECT; /* cache the gateway (sender HW) address */ nd6_llreach_alloc(rt, ifp, LLADDR(sdl), sdl->sdl_alen, TRUE); /* update the llinfo, send a queued packet if there is one */ ln->ln_asked = 0; if (ln->ln_hold != NULL) { struct mbuf *m_hold, *m_hold_next; struct sockaddr_in6 sin6; rtkey_to_sa6(rt, &sin6); /* * reset the ln_hold in advance, to explicitly * prevent a ln_hold lookup in nd6_output() * (wouldn't happen, though...) */ m_hold = ln->ln_hold; ln->ln_hold = NULL; for (; 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 loopback here, so just set * the 2nd argument as the 1st one. */ RT_UNLOCK(rt); nd6_output(ifp, ifp, m_hold, &sin6, rt, NULL); RT_LOCK_SPIN(rt); } } RT_REMREF_LOCKED(rt); RT_UNLOCK(rt); m_freem(m); return; bad: icmp6stat.icp6s_badna++; /* fall through */ freeit: m_freem(m); return; } /* * Neighbor advertisement output handling. * * Based on RFC 2461 * * the following items are not implemented yet: * - proxy advertisement delay rule (RFC2461 7.2.8, last paragraph, SHOULD) * - anycast advertisement delay rule (RFC2461 7.2.7, SHOULD) * * tlladdr - 1 if include target link-layer address * sdl0 - sockaddr_dl (= proxy NA) or NULL */ void nd6_na_output( struct ifnet *ifp, const struct in6_addr *daddr6_0, const struct in6_addr *taddr6, uint32_t flags, int tlladdr, /* 1 if include target link-layer address */ struct sockaddr *sdl0) /* sockaddr_dl (= proxy NA) or NULL */ { struct mbuf *m; struct ip6_hdr *ip6; struct nd_neighbor_advert *nd_na; struct ip6_moptions *im6o = NULL; caddr_t mac = NULL; struct route_in6 ro; struct in6_addr *src, src_storage, daddr6; struct in6_ifaddr *ia; struct sockaddr_in6 dst_sa; int icmp6len, maxlen, error; struct ifnet *outif = NULL; struct ip6_out_args ip6oa; bzero(&ro, sizeof(ro)); daddr6 = *daddr6_0; /* make a local copy for modification */ bzero(&ip6oa, sizeof(ip6oa)); ip6oa.ip6oa_boundif = ifp->if_index; ip6oa.ip6oa_flags = IP6OAF_SELECT_SRCIF | IP6OAF_BOUND_SRCADDR | IP6OAF_AWDL_UNRESTRICTED | IP6OAF_INTCOPROC_ALLOWED | IP6OAF_MANAGEMENT_ALLOWED; ip6oa.ip6oa_sotc = SO_TC_UNSPEC; ip6oa.ip6oa_netsvctype = _NET_SERVICE_TYPE_UNSPEC; ip6oa.ip6oa_flags |= IP6OAF_BOUND_IF; /* estimate the size of message */ maxlen = sizeof(*ip6) + sizeof(*nd_na); maxlen += (sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7; if (max_linkhdr + maxlen >= MCLBYTES) { #if DIAGNOSTIC printf("nd6_na_output: max_linkhdr + maxlen >= MCLBYTES " "(%d + %d > %d)\n", max_linkhdr, maxlen, MCLBYTES); #endif return; } MGETHDR(m, M_DONTWAIT, MT_DATA); /* XXXMAC: mac_create_mbuf_linklayer() probably */ if (m && max_linkhdr + maxlen >= MHLEN) { MCLGET(m, M_DONTWAIT); if ((m->m_flags & M_EXT) == 0) { m_free(m); m = NULL; } } if (m == NULL) { return; } m->m_pkthdr.rcvif = NULL; if (IN6_IS_ADDR_MULTICAST(&daddr6)) { m->m_flags |= M_MCAST; im6o = ip6_allocmoptions(Z_NOWAIT); if (im6o == NULL) { m_freem(m); return; } im6o->im6o_multicast_ifp = ifp; im6o->im6o_multicast_hlim = IPV6_MAXHLIM; im6o->im6o_multicast_loop = 0; } icmp6len = sizeof(*nd_na); m->m_pkthdr.len = m->m_len = sizeof(struct ip6_hdr) + icmp6len; m->m_data += max_linkhdr; /* or MH_ALIGN() equivalent? */ /* fill neighbor advertisement packet */ ip6 = mtod(m, struct ip6_hdr *); ip6->ip6_flow = 0; ip6->ip6_vfc &= ~IPV6_VERSION_MASK; ip6->ip6_vfc |= IPV6_VERSION; ip6->ip6_nxt = IPPROTO_ICMPV6; ip6->ip6_hlim = IPV6_MAXHLIM; if (IN6_IS_ADDR_UNSPECIFIED(&daddr6)) { /* reply to DAD */ daddr6.s6_addr16[0] = IPV6_ADDR_INT16_MLL; daddr6.s6_addr16[1] = 0; daddr6.s6_addr32[1] = 0; daddr6.s6_addr32[2] = 0; daddr6.s6_addr32[3] = IPV6_ADDR_INT32_ONE; if (in6_setscope(&daddr6, ifp, NULL)) { goto bad; } flags &= ~ND_NA_FLAG_SOLICITED; } else { ip6->ip6_dst = daddr6; ip6_output_setdstifscope(m, ifp->if_index, NULL); } SOCKADDR_ZERO(&dst_sa, sizeof(struct sockaddr_in6)); dst_sa.sin6_family = AF_INET6; dst_sa.sin6_len = sizeof(struct sockaddr_in6); dst_sa.sin6_addr = daddr6; /* * Select a source whose scope is the same as that of the dest. */ SOCKADDR_COPY(&dst_sa, &ro.ro_dst, sizeof(dst_sa)); src = in6_selectsrc(&dst_sa, NULL, NULL, &ro, NULL, &src_storage, ip6oa.ip6oa_boundif, &error); if (src == NULL) { nd6log(debug, "nd6_na_output: source can't be " "determined: dst=%s, error=%d\n", ip6_sprintf(&dst_sa.sin6_addr), error); goto bad; } ip6->ip6_src = *src; /* * RFC 4429 requires not setting "override" flag on NA packets sent * from optimistic addresses. */ ia = in6ifa_ifpwithaddr(ifp, src); ip6_output_setsrcifscope(m, ifp->if_index, ia); if (ia != NULL) { if (ia->ia6_flags & IN6_IFF_OPTIMISTIC) { flags &= ~ND_NA_FLAG_OVERRIDE; } ifa_remref(&ia->ia_ifa); } nd_na = (struct nd_neighbor_advert *)(ip6 + 1); nd_na->nd_na_type = ND_NEIGHBOR_ADVERT; nd_na->nd_na_code = 0; nd_na->nd_na_target = *taddr6; in6_clearscope(&nd_na->nd_na_target); /* XXX */ /* * "tlladdr" indicates NS's condition for adding tlladdr or not. * see nd6_ns_input() for details. * Basically, if NS packet is sent to unicast/anycast addr, * target lladdr option SHOULD NOT be included. */ if (tlladdr) { /* * sdl0 != NULL indicates proxy NA. If we do proxy, use * lladdr in sdl0. If we are not proxying (sending NA for * my address) use lladdr configured for the interface. */ if (sdl0 == NULL) { mac = nd6_ifptomac(ifp); } else if (sdl0->sa_family == AF_LINK) { struct sockaddr_dl *sdl; sdl = SDL(sdl0); if (sdl->sdl_alen == ifp->if_addrlen) { mac = LLADDR(sdl); } } } if (tlladdr && mac) { int optlen = sizeof(struct nd_opt_hdr) + ifp->if_addrlen; struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd_na + 1); /* roundup to 8 bytes alignment! */ optlen = (optlen + 7) & ~7; m->m_pkthdr.len += optlen; m->m_len += optlen; icmp6len += optlen; bzero((caddr_t)nd_opt, optlen); nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; nd_opt->nd_opt_len = (uint8_t)(optlen >> 3); bcopy(mac, (caddr_t)(nd_opt + 1), ifp->if_addrlen); } else { flags &= ~ND_NA_FLAG_OVERRIDE; } ip6->ip6_plen = htons((u_short)icmp6len); nd_na->nd_na_flags_reserved = flags; nd_na->nd_na_cksum = 0; nd_na->nd_na_cksum = in6_cksum(m, IPPROTO_ICMPV6, sizeof(struct ip6_hdr), icmp6len); m->m_pkthdr.pkt_flags |= PKTF_INET6_RESOLVE; if (ifp->if_eflags & IFEF_TXSTART) { /* Use control service class if the interface supports * transmit-start model. */ (void) m_set_service_class(m, MBUF_SC_CTL); } ip6oa.ip6oa_flags |= IP6OAF_SKIP_PF; ip6oa.ip6oa_flags |= IP6OAF_DONT_FRAG; ip6_output(m, NULL, NULL, IPV6_OUTARGS, im6o, &outif, &ip6oa); if (outif) { icmp6_ifstat_inc(outif, ifs6_out_msg); icmp6_ifstat_inc(outif, ifs6_out_neighboradvert); ifnet_release(outif); } icmp6stat.icp6s_outhist[ND_NEIGHBOR_ADVERT]++; exit: if (im6o != NULL) { IM6O_REMREF(im6o); } ROUTE_RELEASE(&ro); return; bad: m_freem(m); goto exit; } caddr_t nd6_ifptomac( struct ifnet *ifp) { switch (ifp->if_type) { case IFT_ARCNET: case IFT_ETHER: case IFT_IEEE8023ADLAG: 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_BRIDGE: case IFT_ISO88025: return (caddr_t)IF_LLADDR(ifp); default: return NULL; } } TAILQ_HEAD(dadq_head, dadq); struct dadq { decl_lck_mtx_data(, dad_lock); u_int32_t dad_refcount; /* reference count */ int dad_attached; TAILQ_ENTRY(dadq) dad_list; struct ifaddr *dad_ifa; int dad_count; /* max NS to send */ int dad_ns_tcount; /* # of trials to send NS */ int dad_ns_ocount; /* NS sent so far */ int dad_ns_icount; int dad_na_icount; int dad_ns_lcount; /* looped back NS */ int dad_loopbackprobe; /* probing state for loopback detection */ uint8_t dad_lladdr[ETHER_ADDR_LEN]; uint8_t dad_lladdrlen; #define ND_OPT_NONCE_LEN32 \ ((ND_OPT_NONCE_LEN + sizeof(uint32_t) - 1)/sizeof(uint32_t)) uint32_t dad_nonce[ND_OPT_NONCE_LEN32]; uint32_t dad_same_nonce_count; /* # of consecutive times we've ignored DAD failure because of optimistic DAD */ }; static KALLOC_TYPE_DEFINE(dad_zone, struct dadq, NET_KT_DEFAULT); static struct dadq_head dadq; void nd6_nbr_init(void) { int i; TAILQ_INIT(&dadq); SOCKADDR_ZERO(&hostrtmask, sizeof hostrtmask); hostrtmask.sin6_family = AF_INET6; hostrtmask.sin6_len = sizeof hostrtmask; for (i = 0; i < sizeof hostrtmask.sin6_addr; ++i) { hostrtmask.sin6_addr.s6_addr[i] = 0xff; } } static struct dadq * nd6_dad_find(struct ifaddr *ifa, struct nd_opt_nonce *nonce) { struct dadq *dp; boolean_t same_nonce = false; lck_mtx_lock(&dad6_mutex); for (dp = dadq.tqh_first; dp; dp = dp->dad_list.tqe_next) { DAD_LOCK_SPIN(dp); if (dp->dad_ifa != ifa) { DAD_UNLOCK(dp); continue; } /* * Skip if the nonce matches the received one. * +2 in the length is required because of type and * length fields are included in a header. */ same_nonce = nonce != NULL && nonce->nd_opt_nonce_len == (ND_OPT_NONCE_LEN + 2) / 8 && memcmp(&nonce->nd_opt_nonce[0], &dp->dad_nonce[0], ND_OPT_NONCE_LEN) == 0; if (same_nonce && dp->dad_same_nonce_count <= nd6_dad_nonce_max_count) { nd6log(error, "%s: a looped back NS message is " "detected during DAD for if=%s %s. Ignoring.\n", __func__, if_name(ifa->ifa_ifp), ip6_sprintf(IFA_IN6(ifa))); dp->dad_same_nonce_count++; dp->dad_ns_lcount++; ++ip6stat.ip6s_dad_loopcount; DAD_UNLOCK(dp); continue; } else if (!same_nonce) { // Not the same nonce, reset counter dp->dad_same_nonce_count = 1; } DAD_ADDREF_LOCKED(dp); DAD_UNLOCK(dp); break; } lck_mtx_unlock(&dad6_mutex); return dp; } void nd6_dad_stoptimer( struct ifaddr *ifa) { untimeout((void (*)(void *))nd6_dad_timer, (void *)ifa); } /* * Start Duplicate Address Detection (DAD) for specified interface address. */ void nd6_dad_start( struct ifaddr *ifa, int *tick_delay) /* minimum delay ticks for IFF_UP event */ { struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; struct dadq *dp; if (ifa->ifa_ifp == NULL) { panic("nd6_dad_start: ifa->ifa_ifp == NULL"); } nd6log2(debug, "%s - %s ifp %s ia6_flags 0x%x\n", __func__, ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ia->ia_ifp), ia->ia6_flags); /* * If we don't need DAD, don't do it. * There are several cases: * - DAD is disabled (ip6_dad_count == 0) * - the interface address is anycast */ IFA_LOCK(&ia->ia_ifa); if (!(ia->ia6_flags & IN6_IFF_DADPROGRESS)) { nd6log0(debug, "nd6_dad_start: not a tentative or optimistic address " "%s(%s)\n", ip6_sprintf(&ia->ia_addr.sin6_addr), ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); IFA_UNLOCK(&ia->ia_ifa); return; } if (!ip6_dad_count || (ia->ia6_flags & IN6_IFF_ANYCAST) != 0) { ia->ia6_flags &= ~IN6_IFF_DADPROGRESS; IFA_UNLOCK(&ia->ia_ifa); return; } IFA_UNLOCK(&ia->ia_ifa); if (!(ifa->ifa_ifp->if_flags & IFF_UP) || (ifa->ifa_ifp->if_eflags & IFEF_IPV6_ND6ALT)) { return; } if ((dp = nd6_dad_find(ifa, NULL)) != NULL) { DAD_REMREF(dp); /* DAD already in progress */ return; } dp = zalloc_flags(dad_zone, Z_WAITOK | Z_ZERO); lck_mtx_init(&dp->dad_lock, &ifa_mtx_grp, &ifa_mtx_attr); /* Callee adds one reference for us */ dp = nd6_dad_attach(dp, ifa); nd6log0(debug, "%s: starting %sDAD %sfor %s\n", if_name(ifa->ifa_ifp), (ia->ia6_flags & IN6_IFF_OPTIMISTIC) ? "optimistic " : "", (tick_delay == NULL) ? "immediately " : "", ip6_sprintf(&ia->ia_addr.sin6_addr)); /* * Send NS packet for DAD, ip6_dad_count times. * Note that we must delay the first transmission, if this is the * first packet to be sent from the interface after interface * (re)initialization. */ if (tick_delay == NULL) { u_int32_t retrans; struct nd_ifinfo *ndi = NULL; nd6_dad_ns_output(dp, ifa); ndi = ND_IFINFO(ifa->ifa_ifp); VERIFY(ndi != NULL && ndi->initialized); lck_mtx_lock(&ndi->lock); retrans = ndi->retrans * hz / 1000; lck_mtx_unlock(&ndi->lock); timeout((void (*)(void *))nd6_dad_timer, (void *)ifa, retrans); } else { int ntick; if (*tick_delay == 0) { ntick = random() % (MAX_RTR_SOLICITATION_DELAY * hz); } else { ntick = *tick_delay + random() % (hz / 2); } *tick_delay = ntick; timeout((void (*)(void *))nd6_dad_timer, (void *)ifa, ntick); } DAD_REMREF(dp); /* drop our reference */ } static struct dadq * nd6_dad_attach(struct dadq *dp, struct ifaddr *ifa) { lck_mtx_lock(&dad6_mutex); DAD_LOCK(dp); dp->dad_ifa = ifa; ifa_addref(ifa); /* for dad_ifa */ dp->dad_count = ip6_dad_count; dp->dad_ns_icount = dp->dad_na_icount = 0; dp->dad_ns_ocount = dp->dad_ns_tcount = 0; dp->dad_ns_lcount = dp->dad_loopbackprobe = 0; VERIFY(!dp->dad_attached); dp->dad_same_nonce_count = 1; dp->dad_attached = 1; dp->dad_lladdrlen = 0; DAD_ADDREF_LOCKED(dp); /* for caller */ DAD_ADDREF_LOCKED(dp); /* for dadq_head list */ TAILQ_INSERT_TAIL(&dadq, (struct dadq *)dp, dad_list); DAD_UNLOCK(dp); lck_mtx_unlock(&dad6_mutex); return dp; } static void nd6_dad_detach(struct dadq *dp, struct ifaddr *ifa) { int detached; lck_mtx_lock(&dad6_mutex); DAD_LOCK(dp); if ((detached = dp->dad_attached)) { VERIFY(dp->dad_ifa == ifa); TAILQ_REMOVE(&dadq, (struct dadq *)dp, dad_list); dp->dad_list.tqe_next = NULL; dp->dad_list.tqe_prev = NULL; dp->dad_attached = 0; } DAD_UNLOCK(dp); lck_mtx_unlock(&dad6_mutex); if (detached) { DAD_REMREF(dp); /* drop dadq_head reference */ } } /* * terminate DAD unconditionally. used for address removals. */ void nd6_dad_stop(struct ifaddr *ifa) { struct dadq *dp; dp = nd6_dad_find(ifa, NULL); if (!dp) { /* DAD wasn't started yet */ return; } untimeout((void (*)(void *))nd6_dad_timer, (void *)ifa); nd6_dad_detach(dp, ifa); DAD_REMREF(dp); /* drop our reference */ } static void nd6_unsol_na_output(struct ifaddr *ifa) { struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; struct ifnet *ifp = ifa->ifa_ifp; struct in6_addr saddr6, taddr6; if ((ifp->if_flags & IFF_UP) == 0 || (ifp->if_flags & IFF_RUNNING) == 0 || (ifp->if_eflags & IFEF_IPV6_ND6ALT) != 0) { return; } IFA_LOCK_SPIN(&ia->ia_ifa); taddr6 = ia->ia_addr.sin6_addr; IFA_UNLOCK(&ia->ia_ifa); if (in6_setscope(&taddr6, ifp, NULL) != 0) { return; } saddr6 = in6addr_linklocal_allnodes; if (in6_setscope(&saddr6, ifp, NULL) != 0) { return; } nd6log(info, "%s: sending unsolicited NA\n", if_name(ifa->ifa_ifp)); nd6_na_output(ifp, &saddr6, &taddr6, ND_NA_FLAG_OVERRIDE, 1, NULL); } static void nd6_dad_timer(struct ifaddr *ifa) { struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; struct dadq *dp = NULL; struct nd_ifinfo *ndi = NULL; u_int32_t retrans; /* Sanity check */ if (ia == NULL) { nd6log0(error, "nd6_dad_timer: called with null parameter\n"); goto done; } nd6log2(debug, "%s - %s ifp %s ia6_flags 0x%x\n", __func__, ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ia->ia_ifp), ia->ia6_flags); dp = nd6_dad_find(ifa, NULL); if (dp == NULL) { nd6log0(error, "nd6_dad_timer: DAD structure not found\n"); goto done; } IFA_LOCK(&ia->ia_ifa); if (ia->ia6_flags & IN6_IFF_DUPLICATED) { nd6log0(error, "nd6_dad_timer: called with duplicated address " "%s(%s)\n", ip6_sprintf(&ia->ia_addr.sin6_addr), ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); IFA_UNLOCK(&ia->ia_ifa); goto done; } if ((ia->ia6_flags & IN6_IFF_DADPROGRESS) == 0) { nd6log0(error, "nd6_dad_timer: not a tentative or optimistic " "address %s(%s)\n", ip6_sprintf(&ia->ia_addr.sin6_addr), ifa->ifa_ifp ? if_name(ifa->ifa_ifp) : "???"); IFA_UNLOCK(&ia->ia_ifa); goto done; } IFA_UNLOCK(&ia->ia_ifa); /* timeouted with IFF_{RUNNING,UP} check */ DAD_LOCK(dp); if (dp->dad_ns_tcount > dad_maxtry) { DAD_UNLOCK(dp); nd6log0(info, "%s: could not run DAD, driver problem?\n", if_name(ifa->ifa_ifp)); nd6_dad_detach(dp, ifa); goto done; } /* Need more checks? */ if (dp->dad_ns_ocount < dp->dad_count) { DAD_UNLOCK(dp); /* * We have more NS to go. Send NS packet for DAD. */ nd6_dad_ns_output(dp, ifa); ndi = ND_IFINFO(ifa->ifa_ifp); VERIFY(ndi != NULL && ndi->initialized); lck_mtx_lock(&ndi->lock); retrans = ndi->retrans * hz / 1000; lck_mtx_unlock(&ndi->lock); timeout((void (*)(void *))nd6_dad_timer, (void *)ifa, retrans); } else { /* * We have transmitted sufficient number of DAD packets. * See what we've got. */ if (dp->dad_na_icount > 0 || dp->dad_ns_icount) { /* We've seen NS or NA, means DAD has failed. */ DAD_UNLOCK(dp); nd6log0(info, "%s: duplicate IPv6 address %s if:%s [timer]\n", __func__, ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ia->ia_ifp)); nd6_dad_duplicated(ifa); /* (*dp) will be freed in nd6_dad_duplicated() */ #if SKYWALK SK_NXS_MS_IF_ADDR_GENCNT_INC(ia->ia_ifp); #endif /* SKYWALK */ } else if (dad_enhanced != 0 && dp->dad_ns_lcount > 0 && dp->dad_ns_lcount > dp->dad_loopbackprobe && dp->dad_same_nonce_count > 0 && dp->dad_same_nonce_count > nd6_dad_nonce_max_count) { dp->dad_loopbackprobe = dp->dad_ns_lcount; dp->dad_count = dp->dad_ns_ocount + dad_maxtry - 1; DAD_UNLOCK(dp); ndi = ND_IFINFO(ifa->ifa_ifp); VERIFY(ndi != NULL && ndi->initialized); lck_mtx_lock(&ndi->lock); retrans = ndi->retrans * hz / 1000; lck_mtx_unlock(&ndi->lock); /* * Sec. 4.1 in RFC 7527 requires transmission of * additional probes until the loopback condition * becomes clear when a looped back probe is detected. */ nd6log0(info, "%s: a looped back NS message is detected during DAD for %s. Another DAD probe is being sent on interface %s.\n", __func__, ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ia->ia_ifp)); /* * Send an NS immediately and increase dad_count by * nd6_mmaxtries - 1. */ nd6_dad_ns_output(dp, ifa); timeout((void (*)(void *))nd6_dad_timer, (void *)ifa, retrans); goto done; } else { boolean_t txunsolna; DAD_UNLOCK(dp); /* * We are done with DAD. No NA came, no NS came. * No duplicate address found. */ IFA_LOCK_SPIN(&ia->ia_ifa); ia->ia6_flags &= ~IN6_IFF_DADPROGRESS; IFA_UNLOCK(&ia->ia_ifa); ndi = ND_IFINFO(ifa->ifa_ifp); VERIFY(ndi != NULL && ndi->initialized); lck_mtx_lock(&ndi->lock); txunsolna = (ndi->flags & ND6_IFF_REPLICATED) != 0; lck_mtx_unlock(&ndi->lock); if (txunsolna) { nd6_unsol_na_output(ifa); } nd6log0(debug, "%s: DAD complete for %s - no duplicates found %s\n", if_name(ifa->ifa_ifp), ip6_sprintf(&ia->ia_addr.sin6_addr), txunsolna ? ", tx unsolicited NA with O=1" : "."); if (dp->dad_ns_lcount > 0) { nd6log0(debug, "%s: DAD completed while " "a looped back NS message is detected " "during DAD for %s om interface %s\n", __func__, ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ia->ia_ifp)); } in6_post_msg(ia->ia_ifp, KEV_INET6_NEW_USER_ADDR, ia, dp->dad_lladdr); nd6_dad_detach(dp, ifa); #if SKYWALK SK_NXS_MS_IF_ADDR_GENCNT_INC(ia->ia_ifp); #endif /* SKYWALK */ } } done: if (dp != NULL) { DAD_REMREF(dp); /* drop our reference */ } } static void nd6_dad_duplicated(struct ifaddr *ifa) { struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; struct dadq *dp; struct ifnet *ifp = ifa->ifa_ifp; boolean_t candisable; dp = nd6_dad_find(ifa, NULL); if (dp == NULL) { log(LOG_ERR, "%s: DAD structure not found.\n", __func__); return; } IFA_LOCK(&ia->ia_ifa); DAD_LOCK(dp); nd6log(error, "%s: NS in/out/loopback=%d/%d/%d, NA in=%d\n", __func__, dp->dad_ns_icount, dp->dad_ns_ocount, dp->dad_ns_lcount, dp->dad_na_icount); candisable = FALSE; if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_addr.sin6_addr) && !(ia->ia6_flags & IN6_IFF_SECURED)) { struct in6_addr in6; struct ifaddr *llifa = NULL; struct sockaddr_dl *sdl = NULL; uint8_t *lladdr = dp->dad_lladdr; uint8_t lladdrlen = dp->dad_lladdrlen; /* * To avoid over-reaction, we only apply this logic when we are * very sure that hardware addresses are supposed to be unique. */ switch (ifp->if_type) { case IFT_BRIDGE: case IFT_ETHER: case IFT_FDDI: case IFT_ATM: case IFT_IEEE1394: #ifdef IFT_IEEE80211 case IFT_IEEE80211: #endif /* * Check if our hardware address matches the * link layer information received in the * NS/NA */ llifa = ifp->if_lladdr; IFA_LOCK(llifa); sdl = SDL(llifa->ifa_addr); if (lladdrlen == sdl->sdl_alen && bcmp(lladdr, LLADDR(sdl), lladdrlen) == 0) { candisable = TRUE; } IFA_UNLOCK(llifa); in6 = ia->ia_addr.sin6_addr; if (in6_iid_from_hw(ifp, &in6) != 0) { break; } /* Refine decision about whether IPv6 can be disabled */ if (candisable && !IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { /* * Apply this logic only to the embedded MAC * address form of link-local IPv6 address. */ candisable = FALSE; } else if (lladdr == NULL && IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr, &in6)) { /* * We received a NA with no target link-layer * address option. This means that someone else * has our address. Mark it as a hardware * duplicate so we disable IPv6 later on. */ candisable = TRUE; } break; default: break; } } DAD_UNLOCK(dp); ia->ia6_flags &= ~IN6_IFF_DADPROGRESS; ia->ia6_flags |= IN6_IFF_DUPLICATED; in6_event_enqueue_nwk_wq_entry(IN6_ADDR_MARKED_DUPLICATED, ia->ia_ifa.ifa_ifp, &ia->ia_addr.sin6_addr, 0); IFA_UNLOCK(&ia->ia_ifa); /* increment DAD collision counter */ ++ip6stat.ip6s_dad_collide; /* We are done with DAD, with duplicated address found. (failure) */ untimeout((void (*)(void *))nd6_dad_timer, (void *)ifa); IFA_LOCK(&ia->ia_ifa); log(LOG_ERR, "%s: DAD complete for %s - duplicate found.\n", if_name(ifp), ip6_sprintf(&ia->ia_addr.sin6_addr)); IFA_UNLOCK(&ia->ia_ifa); if (candisable) { struct nd_ifinfo *ndi = ND_IFINFO(ifp); log(LOG_ERR, "%s: possible hardware address duplication " "detected, disabling IPv6 for interface.\n", if_name(ifp)); VERIFY((NULL != ndi) && (TRUE == ndi->initialized)); ndi->flags |= ND6_IFF_IFDISABLED; /* Make sure to set IFEF_IPV6_DISABLED too */ nd6_if_disable(ifp, TRUE); } log(LOG_ERR, "%s: manual intervention may be required.\n", if_name(ifp)); /* Send an event to the configuration agent so that the * duplicate address will be notified to the user and will * be removed. */ in6_post_msg(ifp, KEV_INET6_NEW_USER_ADDR, ia, dp->dad_lladdr); nd6_dad_detach(dp, ifa); DAD_REMREF(dp); /* drop our reference */ } static void nd6_dad_ns_output(struct dadq *dp, struct ifaddr *ifa) { struct in6_ifaddr *ia = (struct in6_ifaddr *)ifa; struct ifnet *ifp = ifa->ifa_ifp; int i = 0; struct in6_addr taddr6; DAD_LOCK(dp); dp->dad_ns_tcount++; if ((ifp->if_flags & IFF_UP) == 0) { DAD_UNLOCK(dp); return; } if ((ifp->if_flags & IFF_RUNNING) == 0) { DAD_UNLOCK(dp); return; } dp->dad_ns_ocount++; DAD_UNLOCK(dp); IFA_LOCK_SPIN(&ia->ia_ifa); taddr6 = ia->ia_addr.sin6_addr; IFA_UNLOCK(&ia->ia_ifa); if (dad_enhanced != 0 && !(ifp->if_flags & IFF_POINTOPOINT)) { for (i = 0; i < ND_OPT_NONCE_LEN32; i++) { dp->dad_nonce[i] = RandomULong(); } /* * XXXHRS: Note that in the case that * DupAddrDetectTransmits > 1, multiple NS messages with * different nonces can be looped back in an unexpected * order. The current implementation recognizes only * the latest nonce on the sender side. Practically it * should work well in almost all cases. */ } nd6_ns_output(ifp, NULL, &taddr6, NULL, (uint8_t *)&dp->dad_nonce[0]); } /* * @brief Called to process DAD NS * * @param ifa is the pointer to the interface's address * @param lladdr is source link layer information * @param lladdrlen is source's linklayer length * * @return void */ static void nd6_dad_ns_input(struct ifaddr *ifa, char *lladdr, int lladdrlen, struct nd_opt_nonce *ndopt_nonce) { struct dadq *dp; VERIFY(ifa != NULL); /* Ignore Nonce option when Enhanced DAD is disabled. */ if (dad_enhanced == 0) { ndopt_nonce = NULL; } dp = nd6_dad_find(ifa, ndopt_nonce); if (dp == NULL) { return; } DAD_LOCK(dp); ++dp->dad_ns_icount; if (lladdr && lladdrlen >= ETHER_ADDR_LEN) { memcpy(dp->dad_lladdr, lladdr, ETHER_ADDR_LEN); /* fine to truncate as it is compared against sdl_alen */ dp->dad_lladdrlen = (uint8_t)lladdrlen; } DAD_UNLOCK(dp); DAD_REMREF(dp); } /* * @brief Called to process received NA for DAD * * @param m is the pointer to the packet's mbuf * @param ifp is the pointer to the interface on which packet * was receicved. * @param taddr is pointer to target's IPv6 address * @param lladdr is target's link layer information * @param lladdrlen is target's linklayer length * * @return NULL if the packet is consumed by DAD processing, else * pointer to the mbuf. */ static struct mbuf * nd6_dad_na_input(struct mbuf *m, struct ifnet *ifp, struct in6_addr *taddr, caddr_t lladdr, int lladdrlen) { struct ifaddr *ifa = NULL; struct in6_ifaddr *ia = NULL; struct dadq *dp = NULL; struct nd_ifinfo *ndi = NULL; boolean_t replicated; ifa = (struct ifaddr *) in6ifa_ifpwithaddr(ifp, taddr); if (ifa == NULL) { return m; } replicated = FALSE; /* Get the ND6_IFF_REPLICATED flag. */ ndi = ND_IFINFO(ifp); if (ndi != NULL && ndi->initialized) { lck_mtx_lock(&ndi->lock); replicated = !!(ndi->flags & ND6_IFF_REPLICATED); lck_mtx_unlock(&ndi->lock); } if (replicated) { nd6log(info, "%s: ignoring duplicate NA on " "replicated interface %s\n", __func__, if_name(ifp)); goto done; } /* Lock the interface address until done (see label below). */ IFA_LOCK(ifa); ia = (struct in6_ifaddr *) ifa; if (!(ia->ia6_flags & IN6_IFF_DADPROGRESS)) { IFA_UNLOCK(ifa); nd6log(info, "%s: ignoring duplicate NA on " "%s [DAD not in progress]\n", __func__, if_name(ifp)); goto done; } /* Some sleep proxies improperly send the client's Ethernet address in * the target link-layer address option, so detect this by comparing * the L2-header source address, if we have seen it, with the target * address, and ignoring the NA if they don't match. */ if (lladdr != NULL && lladdrlen >= ETHER_ADDR_LEN) { struct ip6aux *ip6a = ip6_findaux(m); if (ip6a && (ip6a->ip6a_flags & IP6A_HASEEN) != 0 && bcmp(ip6a->ip6a_ehsrc, lladdr, ETHER_ADDR_LEN) != 0) { IFA_UNLOCK(ifa); nd6log(error, "%s: ignoring duplicate NA on %s " "[eh_src != tgtlladdr]\n", __func__, if_name(ifp)); goto done; } } IFA_UNLOCK(ifa); dp = nd6_dad_find(ifa, NULL); if (dp == NULL) { nd6log(info, "%s: no DAD structure for %s on %s.\n", __func__, ip6_sprintf(taddr), if_name(ifp)); goto done; } DAD_LOCK_SPIN(dp); if (lladdr != NULL && lladdrlen >= ETHER_ADDR_LEN) { memcpy(dp->dad_lladdr, lladdr, ETHER_ADDR_LEN); dp->dad_lladdrlen = (uint8_t)lladdrlen; } dp->dad_na_icount++; DAD_UNLOCK(dp); DAD_REMREF(dp); /* remove the address. */ nd6log(info, "%s: duplicate IPv6 address %s [processing NA on %s]\n", __func__, ip6_sprintf(taddr), if_name(ifp)); done: IFA_LOCK_ASSERT_NOTHELD(ifa); ifa_remref(ifa); m_freem(m); return NULL; } static void dad_addref(struct dadq *dp, int locked) { if (!locked) { DAD_LOCK_SPIN(dp); } else { DAD_LOCK_ASSERT_HELD(dp); } if (++dp->dad_refcount == 0) { panic("%s: dad %p wraparound refcnt", __func__, dp); /* NOTREACHED */ } if (!locked) { DAD_UNLOCK(dp); } } static void dad_remref(struct dadq *dp) { struct ifaddr *ifa; DAD_LOCK_SPIN(dp); if (dp->dad_refcount == 0) { panic("%s: dad %p negative refcnt", __func__, dp); } --dp->dad_refcount; if (dp->dad_refcount > 0) { DAD_UNLOCK(dp); return; } DAD_UNLOCK(dp); if (dp->dad_attached || dp->dad_list.tqe_next != NULL || dp->dad_list.tqe_prev != NULL) { panic("%s: attached dad=%p is being freed", __func__, dp); /* NOTREACHED */ } if ((ifa = dp->dad_ifa) != NULL) { ifa_remref(ifa); /* drop dad_ifa reference */ dp->dad_ifa = NULL; } lck_mtx_destroy(&dp->dad_lock, &ifa_mtx_grp); zfree(dad_zone, dp); } void nd6_llreach_set_reachable(struct ifnet *ifp, void *addr, unsigned int alen) { /* Nothing more to do if it's disabled */ if (nd6_llreach_base == 0) { return; } ifnet_llreach_set_reachable(ifp, ETHERTYPE_IPV6, addr, alen); } void nd6_alt_node_addr_decompose(struct ifnet *ifp, struct sockaddr *sa, struct sockaddr_dl* sdl, struct sockaddr_in6 *sin6) { static const size_t EUI64_LENGTH = 8; VERIFY(nd6_need_cache(ifp)); VERIFY(sa); VERIFY(sdl && (void *)sa != (void *)sdl); VERIFY(sin6 && (void *)sa != (void *)sin6); SOCKADDR_ZERO(sin6, sizeof(*sin6)); sin6->sin6_len = sizeof *sin6; sin6->sin6_family = AF_INET6; SOCKADDR_ZERO(sdl, sizeof(*sdl)); sdl->sdl_len = sizeof *sdl; sdl->sdl_family = AF_LINK; sdl->sdl_type = ifp->if_type; sdl->sdl_index = ifp->if_index; sdl->sdl_nlen = 0; switch (sa->sa_family) { case AF_INET6: { struct sockaddr_in6 *sin6a = SIN6(sa); struct in6_addr *in6 = &sin6a->sin6_addr; VERIFY(sa->sa_len == sizeof *sin6); if (in6->s6_addr[11] == 0xff && in6->s6_addr[12] == 0xfe) { sdl->sdl_alen = ETHER_ADDR_LEN; LLADDR(sdl)[0] = (in6->s6_addr[8] ^ ND6_EUI64_UBIT); LLADDR(sdl)[1] = in6->s6_addr[9]; LLADDR(sdl)[2] = in6->s6_addr[10]; LLADDR(sdl)[3] = in6->s6_addr[13]; LLADDR(sdl)[4] = in6->s6_addr[14]; LLADDR(sdl)[5] = in6->s6_addr[15]; } else { sdl->sdl_alen = EUI64_LENGTH; bcopy(&in6->s6_addr[8], LLADDR(sdl), EUI64_LENGTH); } sdl->sdl_slen = 0; break; } case AF_LINK: { struct sockaddr_dl *sdla = SDL(sa); struct in6_addr *in6 = &sin6->sin6_addr; caddr_t lla = LLADDR(sdla); VERIFY(sa->sa_len <= sizeof(*sdl)); SOCKADDR_COPY(sa, sdl, sa->sa_len); sin6->sin6_scope_id = sdla->sdl_index; if (sin6->sin6_scope_id == 0) { sin6->sin6_scope_id = ifp->if_index; } in6->s6_addr[0] = 0xfe; in6->s6_addr[1] = 0x80; if (sdla->sdl_alen == EUI64_LENGTH) { bcopy(lla, &in6->s6_addr[8], EUI64_LENGTH); } else { VERIFY(sdla->sdl_alen == ETHER_ADDR_LEN); in6->s6_addr[8] = ((uint8_t) lla[0] ^ ND6_EUI64_UBIT); in6->s6_addr[9] = (uint8_t) lla[1]; in6->s6_addr[10] = (uint8_t) lla[2]; in6->s6_addr[11] = 0xff; in6->s6_addr[12] = 0xfe; in6->s6_addr[13] = (uint8_t) lla[3]; in6->s6_addr[14] = (uint8_t) lla[4]; in6->s6_addr[15] = (uint8_t) lla[5]; } break; } default: VERIFY(false); break; } } int nd6_alt_node_present(struct ifnet *ifp, struct sockaddr_in6 *sin6, struct sockaddr_dl *sdl, int32_t rssi, int lqm, int npm) { struct rtentry *rt = NULL; struct llinfo_nd6 *ln = NULL; struct if_llreach *lr = NULL; int nd6_nc_updated = 0; const uint32_t temp_embedded_id = sin6->sin6_addr.s6_addr16[1]; const uint32_t temp_ifscope_id = sin6->sin6_scope_id; if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr)) { if (in6_embedded_scope) { if (temp_embedded_id == 0) { sin6->sin6_addr.s6_addr16[1] = htons(ifp->if_index); } } else if (temp_ifscope_id == 0) { sin6->sin6_scope_id = ifp->if_index; } } nd6_cache_lladdr(ifp, &sin6->sin6_addr, LLADDR(sdl), sdl->sdl_alen, ND_NEIGHBOR_ADVERT, 0, &nd6_nc_updated); LCK_MTX_ASSERT(rnh_lock, LCK_MTX_ASSERT_NOTOWNED); lck_mtx_lock(rnh_lock); rt = rtalloc1_scoped_locked(SA(sin6), 1, 0, ifp->if_index); /* Restore the address that was passed to us */ if (in6_embedded_scope) { if (temp_embedded_id == 0) { sin6->sin6_addr.s6_addr16[1] = 0; } } else if (temp_ifscope_id == 0) { sin6->sin6_scope_id = 0; } if (rt != NULL) { RT_LOCK(rt); VERIFY(rt->rt_flags & RTF_LLINFO); VERIFY(rt->rt_llinfo); ln = rt->rt_llinfo; ND6_CACHE_STATE_TRANSITION(ln, ND6_LLINFO_REACHABLE); ln_setexpire(ln, 0); lr = ln->ln_llreach; if (lr) { IFLR_LOCK(lr); lr->lr_rssi = rssi; lr->lr_lqm = (int32_t) lqm; lr->lr_npm = (int32_t) npm; IFLR_UNLOCK(lr); } RT_UNLOCK(rt); RT_REMREF(rt); } lck_mtx_unlock(rnh_lock); if (rt == NULL) { log(LOG_ERR, "%s: failed to add/update host route to %s.\n", __func__, ip6_sprintf(&sin6->sin6_addr)); #if DEBUG || DEVELOPMENT if (ip6_p2p_debug) { panic("%s: failed to add/update host route to %s.\n", __func__, ip6_sprintf(&sin6->sin6_addr)); } #endif return EHOSTUNREACH; } nd6log(debug, "%s: Successfully added/updated host route to %s [lr=0x%llx]\n", __func__, ip6_sprintf(&sin6->sin6_addr), (uint64_t)VM_KERNEL_ADDRPERM(lr)); /* * nd6_nc_updated not set implies that nothing was updated * in the neighbor cache. Convey that as EEXIST to callers. */ if (nd6_nc_updated == 0) { return EEXIST; } return 0; } int nd6_alt_node_absent(struct ifnet *ifp, struct sockaddr_in6 *sin6, struct sockaddr_dl *sdl) { struct rtentry *rt = NULL; int error = 0; const uint32_t temp_embedded_id = sin6->sin6_addr.s6_addr16[1]; const uint32_t temp_ifscope_id = sin6->sin6_scope_id; nd6log(debug, "%s: host route to %s\n", __func__, ip6_sprintf(&sin6->sin6_addr)); if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr)) { if (in6_embedded_scope) { if (temp_embedded_id == 0) { sin6->sin6_addr.s6_addr16[1] = htons(ifp->if_index); } } else if (temp_ifscope_id == 0) { sin6->sin6_scope_id = ifp->if_index; } } LCK_MTX_ASSERT(rnh_lock, LCK_MTX_ASSERT_NOTOWNED); lck_mtx_lock(rnh_lock); rt = rtalloc1_scoped_locked(SA(sin6), 0, 0, ifp->if_index); /* Restore the address that was passed to us */ if (in6_embedded_scope) { if (temp_embedded_id == 0) { sin6->sin6_addr.s6_addr16[1] = 0; } } else if (temp_ifscope_id == 0) { sin6->sin6_scope_id = 0; } if (rt != NULL) { RT_LOCK(rt); if (IS_DYNAMIC_DIRECT_HOSTROUTE(rt)) { /* * Copy the link layer information in SDL when present * as it later gets used to issue the kernel event for * node absence. */ if (sdl != NULL && rt->rt_gateway != NULL && rt->rt_gateway->sa_family == AF_LINK && SDL(rt->rt_gateway)->sdl_len <= sizeof(*sdl)) { SOCKADDR_COPY(rt->rt_gateway, sdl, SDL(rt->rt_gateway)->sdl_len); } rt->rt_flags |= RTF_CONDEMNED; RT_UNLOCK(rt); error = rtrequest_locked(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 0, (struct rtentry **)NULL); rtfree_locked(rt); } else { error = EHOSTUNREACH; RT_REMREF_LOCKED(rt); RT_UNLOCK(rt); } } else { error = EHOSTUNREACH; } if (error == 0) { nd6log(debug, "%s: Successfully deleted host route to %s " "for interface %s.\n", __func__, ip6_sprintf(&sin6->sin6_addr), ifp->if_xname); } else { nd6log(error, "%s: Failed to delete host route to %s " "for interface %s with error :%d.\n", __func__, ip6_sprintf(&sin6->sin6_addr), ifp->if_xname, error); } lck_mtx_unlock(rnh_lock); return error; }