/* * Copyright (c) 2003-2021 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. */ /* * Copyright (c) 1982, 1986, 1988, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if INET #include #include #endif /* INET */ #include #include #include #include #include #include #include #include #include #include #include #if IPSEC #include #include extern int ipsec_bypass; #endif /* IPSEC */ #if DUMMYNET #include #endif /* DUMMYNET */ /* we need it for NLOOP. */ #include "loop.h" #if PF #include #endif /* PF */ #include struct ip6protosw *ip6_protox[IPPROTO_MAX]; static LCK_GRP_DECLARE(in6_ifaddr_rwlock_grp, "in6_ifaddr_rwlock"); LCK_RW_DECLARE(in6_ifaddr_rwlock, &in6_ifaddr_rwlock_grp); /* Protected by in6_ifaddr_rwlock */ struct in6_ifaddrhead in6_ifaddrhead; uint32_t in6_ifaddrlist_genid = 0; struct in6_ifaddrhashhead * in6_ifaddrhashtbl; uint32_t in6_ifaddrhmask; #define IN6ADDR_NHASH 61 u_int32_t in6addr_nhash = 0; /* hash table size */ u_int32_t in6addr_hashp = 0; /* next largest prime */ #define IN6_IFSTAT_REQUIRE_ALIGNED_64(f) \ _CASSERT(!(offsetof(struct in6_ifstat, f) % sizeof (uint64_t))) #define ICMP6_IFSTAT_REQUIRE_ALIGNED_64(f) \ _CASSERT(!(offsetof(struct icmp6_ifstat, f) % sizeof (uint64_t))) struct ip6stat ip6stat; LCK_ATTR_DECLARE(ip6_mutex_attr, 0, 0); LCK_GRP_DECLARE(ip6_mutex_grp, "ip6"); LCK_MTX_DECLARE_ATTR(proxy6_lock, &ip6_mutex_grp, &ip6_mutex_attr); LCK_MTX_DECLARE_ATTR(nd6_mutex_data, &ip6_mutex_grp, &ip6_mutex_attr); extern int loopattach_done; extern void addrsel_policy_init(void); static int sysctl_reset_ip6_input_stats SYSCTL_HANDLER_ARGS; static int sysctl_ip6_input_measure_bins SYSCTL_HANDLER_ARGS; static int sysctl_ip6_input_getperf SYSCTL_HANDLER_ARGS; static void ip6_init_delayed(void); static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *); static void in6_ifaddrhashtbl_init(void); static struct m_tag *m_tag_kalloc_inet6(u_int32_t id, u_int16_t type, uint16_t len, int wait); static void m_tag_kfree_inet6(struct m_tag *tag); #if NSTF extern void stfattach(void); #endif /* NSTF */ SYSCTL_DECL(_net_inet6_ip6); static uint32_t ip6_adj_clear_hwcksum = 0; SYSCTL_UINT(_net_inet6_ip6, OID_AUTO, adj_clear_hwcksum, CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_adj_clear_hwcksum, 0, "Invalidate hwcksum info when adjusting length"); static uint32_t ip6_adj_partial_sum = 1; SYSCTL_UINT(_net_inet6_ip6, OID_AUTO, adj_partial_sum, CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_adj_partial_sum, 0, "Perform partial sum adjustment of trailing bytes at IP layer"); static int ip6_input_measure = 0; SYSCTL_PROC(_net_inet6_ip6, OID_AUTO, input_perf, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_input_measure, 0, sysctl_reset_ip6_input_stats, "I", "Do time measurement"); static uint64_t ip6_input_measure_bins = 0; SYSCTL_PROC(_net_inet6_ip6, OID_AUTO, input_perf_bins, CTLTYPE_QUAD | CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_input_measure_bins, 0, sysctl_ip6_input_measure_bins, "I", "bins for chaining performance data histogram"); static net_perf_t net_perf; SYSCTL_PROC(_net_inet6_ip6, OID_AUTO, input_perf_data, CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, sysctl_ip6_input_getperf, "S,net_perf", "IP6 input performance data (struct net_perf, net/net_perf.h)"); /* * ip6_checkinterface controls the receive side of the models for multihoming * that are discussed in RFC 1122. * * sysctl_ip6_checkinterface values are: * IP6_CHECKINTERFACE_WEAK_ES: * This corresponds to the Weak End-System model where incoming packets from * any interface are accepted provided the destination address of the incoming packet * is assigned to some interface. * * IP6_CHECKINTERFACE_HYBRID_ES: * The Hybrid End-System model use the Strong End-System for tunnel interfaces * (ipsec and utun) and the weak End-System model for other interfaces families. * This prevents a rogue middle box to probe for signs of TCP connections * that use the tunnel interface. * * IP6_CHECKINTERFACE_STRONG_ES: * The Strong model model requires the packet arrived on an interface that * is assigned the destination address of the packet. * * Since the routing table and transmit implementation do not implement the Strong ES model, * setting this to a value different from IP6_CHECKINTERFACE_WEAK_ES may lead to unexpected results. * * When forwarding is enabled, the system reverts to the Weak ES model as a router * is expected by design to receive packets from several interfaces to the same address. */ #define IP6_CHECKINTERFACE_WEAK_ES 0 #define IP6_CHECKINTERFACE_HYBRID_ES 1 #define IP6_CHECKINTERFACE_STRONG_ES 2 static int ip6_checkinterface = IP6_CHECKINTERFACE_HYBRID_ES; static int sysctl_ip6_checkinterface SYSCTL_HANDLER_ARGS; SYSCTL_PROC(_net_inet6_ip6, OID_AUTO, check_interface, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, 0, 0, sysctl_ip6_checkinterface, "I", "Verify packet arrives on correct interface"); #if (DEBUG || DEVELOPMENT) #define IP6_CHECK_IFDEBUG 1 #else #define IP6_CHECK_IFDEBUG 0 #endif /* (DEBUG || DEVELOPMENT) */ static int ip6_checkinterface_debug = IP6_CHECK_IFDEBUG; SYSCTL_INT(_net_inet6_ip6, OID_AUTO, checkinterface_debug, CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_checkinterface_debug, IP6_CHECK_IFDEBUG, ""); typedef enum ip6_check_if_result { IP6_CHECK_IF_NONE = 0, IP6_CHECK_IF_OURS = 1, IP6_CHECK_IF_DROP = 2, IP6_CHECK_IF_FORWARD = 3 } ip6_check_if_result_t; static ip6_check_if_result_t ip6_input_check_interface(struct mbuf *, struct ip6_hdr *, struct ifnet *, struct route_in6 *rin6, struct ifnet **); /* * On platforms which require strict alignment (currently for anything but * i386 or x86_64 or arm64), check if the IP header pointer is 32-bit aligned; if not, * copy the contents of the mbuf chain into a new chain, and free the original * one. Create some head room in the first mbuf of the new chain, in case * it's needed later on. * * RFC 2460 says that IPv6 headers are 64-bit aligned, but network interfaces * mostly align to 32-bit boundaries. Care should be taken never to use 64-bit * load/store operations on the fields in IPv6 headers. */ #if defined(__i386__) || defined(__x86_64__) || defined(__arm64__) #define IP6_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do { } while (0) #else /* !__i386__ && !__x86_64__ && !__arm64__ */ #define IP6_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do { \ if (!IP6_HDR_ALIGNED_P(mtod(_m, caddr_t))) { \ struct mbuf *_n; \ struct ifnet *__ifp = (_ifp); \ os_atomic_inc(&(__ifp)->if_alignerrs, relaxed); \ if (((_m)->m_flags & M_PKTHDR) && \ (_m)->m_pkthdr.pkt_hdr != NULL) \ (_m)->m_pkthdr.pkt_hdr = NULL; \ _n = m_defrag_offset(_m, max_linkhdr, M_NOWAIT); \ if (_n == NULL) { \ ip6stat.ip6s_toosmall++; \ m_freem(_m); \ (_m) = NULL; \ _action; \ } else { \ VERIFY(_n != (_m)); \ (_m) = _n; \ } \ } \ } while (0) #endif /* !__i386__ && !__x86_64___ && !__arm64__ */ static void ip6_proto_input(protocol_family_t protocol, mbuf_t packet) { #pragma unused(protocol) #if INET struct timeval start_tv; if (ip6_input_measure) { net_perf_start_time(&net_perf, &start_tv); } #endif /* INET */ ip6_input(packet); #if INET if (ip6_input_measure) { net_perf_measure_time(&net_perf, &start_tv, 1); net_perf_histogram(&net_perf, 1); } #endif /* INET */ } /* * IP6 initialization: fill in IP6 protocol switch table. * All protocols not implemented in kernel go to raw IP6 protocol handler. */ void ip6_init(struct ip6protosw *pp, struct domain *dp) { static int ip6_initialized = 0; struct protosw *pr; struct timeval tv; int i; domain_unguard_t unguard; domain_proto_mtx_lock_assert_held(); VERIFY((pp->pr_flags & (PR_INITIALIZED | PR_ATTACHED)) == PR_ATTACHED); _CASSERT((sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr)) <= _MHLEN); if (ip6_initialized) { return; } ip6_initialized = 1; eventhandler_lists_ctxt_init(&in6_evhdlr_ctxt); (void)EVENTHANDLER_REGISTER(&in6_evhdlr_ctxt, in6_event, in6_eventhdlr_callback, eventhandler_entry_dummy_arg, EVENTHANDLER_PRI_ANY); eventhandler_lists_ctxt_init(&in6_clat46_evhdlr_ctxt); (void)EVENTHANDLER_REGISTER(&in6_clat46_evhdlr_ctxt, in6_clat46_event, in6_clat46_eventhdlr_callback, eventhandler_entry_dummy_arg, EVENTHANDLER_PRI_ANY); for (i = 0; i < IN6_EVENT_MAX; i++) { VERIFY(in6_event2kev_array[i].in6_event_code == i); } pr = pffindproto_locked(PF_INET6, IPPROTO_RAW, SOCK_RAW); if (pr == NULL) { panic("%s: Unable to find [PF_INET6,IPPROTO_RAW,SOCK_RAW]", __func__); /* NOTREACHED */ } /* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */ for (i = 0; i < IPPROTO_MAX; i++) { ip6_protox[i] = (struct ip6protosw *)pr; } /* * Cycle through IP protocols and put them into the appropriate place * in ip6_protox[], skipping protocols IPPROTO_{IP,RAW}. */ VERIFY(dp == inet6domain && dp->dom_family == PF_INET6); TAILQ_FOREACH(pr, &dp->dom_protosw, pr_entry) { VERIFY(pr->pr_domain == dp); if (pr->pr_protocol != 0 && pr->pr_protocol != IPPROTO_RAW) { /* Be careful to only index valid IP protocols. */ if (pr->pr_protocol < IPPROTO_MAX) { ip6_protox[pr->pr_protocol] = (struct ip6protosw *)pr; } } } TAILQ_INIT(&in6_ifaddrhead); in6_ifaddrhashtbl_init(); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_receive); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_hdrerr); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_toobig); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_noroute); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_addrerr); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_protounknown); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_truncated); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_discard); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_deliver); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_forward); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_request); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_discard); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_fragok); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_fragfail); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_fragcreat); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_reass_reqd); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_reass_ok); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_reass_fail); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_mcast); IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_mcast); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_msg); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_error); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_dstunreach); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_adminprohib); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_timeexceed); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_paramprob); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_pkttoobig); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_echo); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_echoreply); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_routersolicit); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_routeradvert); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_neighborsolicit); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_neighboradvert); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_redirect); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_mldquery); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_mldreport); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_mlddone); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_msg); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_error); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_dstunreach); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_adminprohib); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_timeexceed); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_paramprob); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_pkttoobig); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_echo); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_echoreply); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_routersolicit); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_routeradvert); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_neighborsolicit); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_neighboradvert); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_redirect); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_mldquery); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_mldreport); ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_mlddone); getmicrotime(&tv); ip6_desync_factor = (RandomULong() ^ tv.tv_usec) % MAX_TEMP_DESYNC_FACTOR; PE_parse_boot_argn("in6_embedded_scope", &in6_embedded_scope, sizeof(in6_embedded_scope)); PE_parse_boot_argn("ip6_checkinterface", &i, sizeof(i)); switch (i) { case IP6_CHECKINTERFACE_WEAK_ES: case IP6_CHECKINTERFACE_HYBRID_ES: case IP6_CHECKINTERFACE_STRONG_ES: ip6_checkinterface = i; break; default: break; } in6_ifaddr_init(); ip6_moptions_init(); nd6_init(); frag6_init(); icmp6_init(NULL, dp); addrsel_policy_init(); /* * P2P interfaces often route the local address to the loopback * interface. At this point, lo0 hasn't been initialized yet, which * means that we need to delay the IPv6 configuration of lo0. */ net_init_add(ip6_init_delayed); unguard = domain_unguard_deploy(); i = proto_register_input(PF_INET6, ip6_proto_input, NULL, 0); if (i != 0) { panic("%s: failed to register PF_INET6 protocol: %d", __func__, i); /* NOTREACHED */ } domain_unguard_release(unguard); } static void ip6_init_delayed(void) { (void) in6_ifattach_prelim(lo_ifp); /* timer for regeneranation of temporary addresses randomize ID */ timeout(in6_tmpaddrtimer, NULL, (ip6_temp_preferred_lifetime - ip6_desync_factor - ip6_temp_regen_advance) * hz); #if NSTF stfattach(); #endif /* NSTF */ } static void ip6_input_adjust(struct mbuf *m, struct ip6_hdr *ip6, uint32_t plen, struct ifnet *inifp) { boolean_t adjust = TRUE; uint32_t tot_len = sizeof(*ip6) + plen; ASSERT(m_pktlen(m) > tot_len); /* * Invalidate hardware checksum info if ip6_adj_clear_hwcksum * is set; useful to handle buggy drivers. Note that this * should not be enabled by default, as we may get here due * to link-layer padding. */ if (ip6_adj_clear_hwcksum && (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) && !(inifp->if_flags & IFF_LOOPBACK) && !(m->m_pkthdr.pkt_flags & PKTF_LOOP)) { m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID; m->m_pkthdr.csum_data = 0; ip6stat.ip6s_adj_hwcsum_clr++; } /* * If partial checksum information is available, subtract * out the partial sum of postpended extraneous bytes, and * update the checksum metadata accordingly. By doing it * here, the upper layer transport only needs to adjust any * prepended extraneous bytes (else it will do both.) */ if (ip6_adj_partial_sum && (m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PARTIAL)) == (CSUM_DATA_VALID | CSUM_PARTIAL)) { m->m_pkthdr.csum_rx_val = m_adj_sum16(m, m->m_pkthdr.csum_rx_start, m->m_pkthdr.csum_rx_start, (tot_len - m->m_pkthdr.csum_rx_start), m->m_pkthdr.csum_rx_val); } else if ((m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PARTIAL)) == (CSUM_DATA_VALID | CSUM_PARTIAL)) { /* * If packet has partial checksum info and we decided not * to subtract the partial sum of postpended extraneous * bytes here (not the default case), leave that work to * be handled by the other layers. For now, only TCP, UDP * layers are capable of dealing with this. For all other * protocols (including fragments), trim and ditch the * partial sum as those layers might not implement partial * checksumming (or adjustment) at all. */ if (ip6->ip6_nxt == IPPROTO_TCP || ip6->ip6_nxt == IPPROTO_UDP) { adjust = FALSE; } else { m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID; m->m_pkthdr.csum_data = 0; ip6stat.ip6s_adj_hwcsum_clr++; } } if (adjust) { ip6stat.ip6s_adj++; if (m->m_len == m->m_pkthdr.len) { m->m_len = tot_len; m->m_pkthdr.len = tot_len; } else { m_adj(m, tot_len - m->m_pkthdr.len); } } } static ip6_check_if_result_t ip6_input_check_interface(struct mbuf *m, struct ip6_hdr *ip6, struct ifnet *inifp, struct route_in6 *rin6, struct ifnet **deliverifp) { struct in6_ifaddr *ia6 = NULL; struct in6_addr tmp_dst = ip6->ip6_dst; /* copy to avoid unaligned access */ struct in6_ifaddr *best_ia6 = NULL; uint32_t dst_ifscope = IFSCOPE_NONE; ip6_check_if_result_t result = IP6_CHECK_IF_NONE; *deliverifp = NULL; if (m->m_pkthdr.pkt_flags & PKTF_IFAINFO) { dst_ifscope = m->m_pkthdr.dst_ifindex; } else { dst_ifscope = inifp->if_index; } /* * Check for exact addresses in the hash bucket. */ lck_rw_lock_shared(&in6_ifaddr_rwlock); TAILQ_FOREACH(ia6, IN6ADDR_HASH(&tmp_dst), ia6_hash) { /* * TODO: should we accept loopback */ if (in6_are_addr_equal_scoped(&ia6->ia_addr.sin6_addr, &tmp_dst, ia6->ia_ifp->if_index, dst_ifscope)) { if ((ia6->ia6_flags & (IN6_IFF_NOTREADY | IN6_IFF_CLAT46))) { continue; } best_ia6 = ia6; if (ia6->ia_ifp == inifp) { /* * TODO: should we also accept locally originated packets * or from loopback ??? */ break; } /* * Continue the loop in case there's a exact match with another * interface */ } } if (best_ia6 != NULL) { if (best_ia6->ia_ifp != inifp && ip6_forwarding == 0 && ((ip6_checkinterface == IP6_CHECKINTERFACE_HYBRID_ES && (best_ia6->ia_ifp->if_family == IFNET_FAMILY_IPSEC || best_ia6->ia_ifp->if_family == IFNET_FAMILY_UTUN)) || ip6_checkinterface == IP6_CHECKINTERFACE_STRONG_ES)) { /* * Drop when interface address check is strict and forwarding * is disabled */ result = IP6_CHECK_IF_DROP; } else { result = IP6_CHECK_IF_OURS; *deliverifp = best_ia6->ia_ifp; ip6_setdstifaddr_info(m, 0, best_ia6); ip6_setsrcifaddr_info(m, best_ia6->ia_ifp->if_index, NULL); } } lck_rw_done(&in6_ifaddr_rwlock); if (result == IP6_CHECK_IF_NONE) { /* * Slow path: route lookup. */ struct sockaddr_in6 *dst6; dst6 = SIN6(&rin6->ro_dst); dst6->sin6_len = sizeof(struct sockaddr_in6); dst6->sin6_family = AF_INET6; dst6->sin6_addr = ip6->ip6_dst; if (!in6_embedded_scope && IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { dst6->sin6_scope_id = dst_ifscope; } rtalloc_scoped_ign((struct route *)rin6, RTF_PRCLONING, IFSCOPE_NONE); if (rin6->ro_rt != NULL) { RT_LOCK_SPIN(rin6->ro_rt); } #define rt6_key(r) (SIN6((r)->rt_nodes->rn_key)) /* * Accept the packet if the forwarding interface to the destination * according to the routing table is the loopback interface, * unless the associated route has a gateway. * Note that this approach causes to accept a packet if there is a * route to the loopback interface for the destination of the packet. * But we think it's even useful in some situations, e.g. when using * a special daemon which wants to intercept the packet. * * XXX: some OSes automatically make a cloned route for the destination * of an outgoing packet. If the outgoing interface of the packet * is a loopback one, the kernel would consider the packet to be * accepted, even if we have no such address assinged on the interface. * We check the cloned flag of the route entry to reject such cases, * assuming that route entries for our own addresses are not made by * cloning (it should be true because in6_addloop explicitly installs * the host route). However, we might have to do an explicit check * while it would be less efficient. Or, should we rather install a * reject route for such a case? */ if (rin6->ro_rt != NULL && (rin6->ro_rt->rt_flags & (RTF_HOST | RTF_GATEWAY)) == RTF_HOST && #if RTF_WASCLONED !(rin6->ro_rt->rt_flags & RTF_WASCLONED) && #endif rin6->ro_rt->rt_ifp->if_type == IFT_LOOP) { ia6 = (struct in6_ifaddr *)rin6->ro_rt->rt_ifa; /* * Packets to a tentative, duplicated, or somehow invalid * address must not be accepted. * * For performance, test without acquiring the address lock; * a lot of things in the address are set once and never * changed (e.g. ia_ifp.) */ if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) { /* this address is ready */ result = IP6_CHECK_IF_OURS; *deliverifp = ia6->ia_ifp; /* correct? */ /* * record dst address information into mbuf. */ (void) ip6_setdstifaddr_info(m, 0, ia6); (void) ip6_setsrcifaddr_info(m, ia6->ia_ifp->if_index, NULL); } } if (rin6->ro_rt != NULL) { RT_UNLOCK(rin6->ro_rt); } } if (result == IP6_CHECK_IF_NONE) { if (ip6_forwarding == 0) { result = IP6_CHECK_IF_DROP; } else { result = IP6_CHECK_IF_FORWARD; ip6_setdstifaddr_info(m, inifp->if_index, NULL); ip6_setsrcifaddr_info(m, inifp->if_index, NULL); } } if (result == IP6_CHECK_IF_OURS && *deliverifp != inifp) { ASSERT(*deliverifp != NULL); ip6stat.ip6s_rcv_if_weak_match++; /* Logging is too noisy when forwarding is enabled */ if (ip6_checkinterface_debug != IP6_CHECKINTERFACE_WEAK_ES && ip6_forwarding != 0) { char src_str[MAX_IPv6_STR_LEN]; char dst_str[MAX_IPv6_STR_LEN]; inet_ntop(AF_INET6, &ip6->ip6_src, src_str, sizeof(src_str)); inet_ntop(AF_INET6, &ip6->ip6_dst, dst_str, sizeof(dst_str)); os_log_info(OS_LOG_DEFAULT, "%s: weak ES interface match to %s for packet from %s to %s proto %u received via %s", __func__, (*deliverifp)->if_xname, src_str, dst_str, ip6->ip6_nxt, inifp->if_xname); } } else if (result == IP6_CHECK_IF_DROP) { ip6stat.ip6s_rcv_if_no_match++; if (ip6_checkinterface_debug > 0) { char src_str[MAX_IPv6_STR_LEN]; char dst_str[MAX_IPv6_STR_LEN]; inet_ntop(AF_INET6, &ip6->ip6_src, src_str, sizeof(src_str)); inet_ntop(AF_INET6, &ip6->ip6_dst, dst_str, sizeof(dst_str)); os_log(OS_LOG_DEFAULT, "%s: no interface match for packet from %s to %s proto %u received via %s", __func__, src_str, dst_str, ip6->ip6_nxt, inifp->if_xname); } } return result; } void ip6_input(struct mbuf *m) { struct ip6_hdr *ip6; int off = sizeof(struct ip6_hdr), nest; u_int32_t plen; u_int32_t rtalert = ~0; int nxt = 0, ours = 0; struct ifnet *inifp, *deliverifp = NULL; ipfilter_t inject_ipfref = NULL; int seen = 1; #if DUMMYNET struct m_tag *tag; struct ip_fw_args args = {}; #endif /* DUMMYNET */ struct route_in6 rin6 = {}; /* * Check if the packet we received is valid after interface filter * processing */ MBUF_INPUT_CHECK(m, m->m_pkthdr.rcvif); inifp = m->m_pkthdr.rcvif; VERIFY(inifp != NULL); /* Perform IP header alignment fixup, if needed */ IP6_HDR_ALIGNMENT_FIXUP(m, inifp, return ); m->m_pkthdr.pkt_flags &= ~PKTF_FORWARDED; #if IPSEC /* * should the inner packet be considered authentic? * see comment in ah4_input(). */ m->m_flags &= ~M_AUTHIPHDR; m->m_flags &= ~M_AUTHIPDGM; #endif /* IPSEC */ /* * make sure we don't have onion peering information into m_aux. */ ip6_delaux(m); #if DUMMYNET if ((tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_DUMMYNET)) != NULL) { struct dn_pkt_tag *dn_tag; dn_tag = (struct dn_pkt_tag *)(tag->m_tag_data); args.fwa_pf_rule = dn_tag->dn_pf_rule; m_tag_delete(m, tag); } if (args.fwa_pf_rule) { ip6 = mtod(m, struct ip6_hdr *); /* In case PF got disabled */ goto check_with_pf; } #endif /* DUMMYNET */ /* * No need to process packet twice if we've already seen it. */ inject_ipfref = ipf_get_inject_filter(m); if (inject_ipfref != NULL) { ip6 = mtod(m, struct ip6_hdr *); nxt = ip6->ip6_nxt; seen = 0; goto injectit; } else { seen = 1; } if (__improbable(m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT)) { if_ports_used_match_mbuf(inifp, PF_INET6, m); } /* * mbuf statistics */ if (m->m_flags & M_EXT) { if (m->m_next != NULL) { ip6stat.ip6s_mext2m++; } else { ip6stat.ip6s_mext1++; } } else { #define M2MMAX (sizeof (ip6stat.ip6s_m2m) / sizeof (ip6stat.ip6s_m2m[0])) if (m->m_next != NULL) { if (m->m_pkthdr.pkt_flags & PKTF_LOOP) { /* XXX */ ip6stat.ip6s_m2m[ifnet_index(lo_ifp)]++; } else if (inifp->if_index < M2MMAX) { ip6stat.ip6s_m2m[inifp->if_index]++; } else { ip6stat.ip6s_m2m[0]++; } } else { ip6stat.ip6s_m1++; } #undef M2MMAX } /* * Drop the packet if IPv6 operation is disabled on the interface. */ if (inifp->if_eflags & IFEF_IPV6_DISABLED) { goto bad; } in6_ifstat_inc_na(inifp, ifs6_in_receive); ip6stat.ip6s_total++; /* * L2 bridge code and some other code can return mbuf chain * that does not conform to KAME requirement. too bad. * XXX: fails to join if interface MTU > MCLBYTES. jumbogram? */ if (m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) { struct mbuf *n; MGETHDR(n, M_DONTWAIT, MT_HEADER); /* MAC-OK */ if (n) { M_COPY_PKTHDR(n, m); } if (n && m->m_pkthdr.len > MHLEN) { MCLGET(n, M_DONTWAIT); if ((n->m_flags & M_EXT) == 0) { m_freem(n); n = NULL; } } if (n == NULL) { goto bad; } m_copydata(m, 0, m->m_pkthdr.len, mtod(n, caddr_t)); n->m_len = m->m_pkthdr.len; m_freem(m); m = n; } IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), { goto done; }); if (m->m_len < sizeof(struct ip6_hdr)) { if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) { ip6stat.ip6s_toosmall++; in6_ifstat_inc(inifp, ifs6_in_hdrerr); goto done; } } ip6 = mtod(m, struct ip6_hdr *); if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { ip6stat.ip6s_badvers++; in6_ifstat_inc(inifp, ifs6_in_hdrerr); goto bad; } ip6stat.ip6s_nxthist[ip6->ip6_nxt]++; /* * Check against address spoofing/corruption. */ if (!(m->m_pkthdr.pkt_flags & PKTF_LOOP) && IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src)) { ip6stat.ip6s_badscope++; in6_ifstat_inc(inifp, ifs6_in_addrerr); goto bad; } if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) || IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) { /* * XXX: "badscope" is not very suitable for a multicast source. */ ip6stat.ip6s_badscope++; in6_ifstat_inc(inifp, ifs6_in_addrerr); goto bad; } if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) && !(m->m_pkthdr.pkt_flags & PKTF_LOOP)) { /* * In this case, the packet should come from the loopback * interface. However, we cannot just check the if_flags, * because ip6_mloopback() passes the "actual" interface * as the outgoing/incoming interface. */ ip6stat.ip6s_badscope++; in6_ifstat_inc(inifp, ifs6_in_addrerr); goto bad; } /* * The following check is not documented in specs. A malicious * party may be able to use IPv4 mapped addr to confuse tcp/udp stack * and bypass security checks (act as if it was from 127.0.0.1 by using * IPv6 src ::ffff:127.0.0.1). Be cautious. * * This check chokes if we are in an SIIT cloud. As none of BSDs * support IPv4-less kernel compilation, we cannot support SIIT * environment at all. So, it makes more sense for us to reject any * malicious packets for non-SIIT environment, than try to do a * partial support for SIIT environment. */ if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { ip6stat.ip6s_badscope++; in6_ifstat_inc(inifp, ifs6_in_addrerr); goto bad; } if (((ntohl(ip6->ip6_flow & IPV6_FLOW_ECN_MASK) >> 20) & IPTOS_ECN_ECT1) == IPTOS_ECN_ECT1) { m->m_pkthdr.pkt_ext_flags |= PKTF_EXT_L4S; } #if 0 /* * Reject packets with IPv4 compatible addresses (auto tunnel). * * The code forbids auto tunnel relay case in RFC1933 (the check is * stronger than RFC1933). We may want to re-enable it if mech-xx * is revised to forbid relaying case. */ if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) || IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) { ip6stat.ip6s_badscope++; in6_ifstat_inc(inifp, ifs6_in_addrerr); goto bad; } #endif /* * Naively assume we can attribute inbound data to the route we would * use to send to this destination. Asymetric routing breaks this * assumption, but it still allows us to account for traffic from * a remote node in the routing table. * this has a very significant performance impact so we bypass * if nstat_collect is disabled. We may also bypass if the * protocol is tcp in the future because tcp will have a route that * we can use to attribute the data to. That does mean we would not * account for forwarded tcp traffic. */ if (nstat_collect) { struct rtentry *rte = ifnet_cached_rtlookup_inet6(inifp, &ip6->ip6_src); if (rte != NULL) { nstat_route_rx(rte, 1, m->m_pkthdr.len, 0); rtfree(rte); } } #if DUMMYNET check_with_pf: #endif /* DUMMYNET */ #if PF /* Invoke inbound packet filter */ if (PF_IS_ENABLED) { int error; #if DUMMYNET error = pf_af_hook(inifp, NULL, &m, AF_INET6, TRUE, &args); #else /* !DUMMYNET */ error = pf_af_hook(inifp, NULL, &m, AF_INET6, TRUE, NULL); #endif /* !DUMMYNET */ if (error != 0 || m == NULL) { if (m != NULL) { panic("%s: unexpected packet %p", __func__, m); /* NOTREACHED */ } /* Already freed by callee */ goto done; } ip6 = mtod(m, struct ip6_hdr *); } #endif /* PF */ /* drop packets if interface ID portion is already filled */ if (!(inifp->if_flags & IFF_LOOPBACK) && !(m->m_pkthdr.pkt_flags & PKTF_LOOP)) { if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src) && ip6->ip6_src.s6_addr16[1]) { ip6stat.ip6s_badscope++; goto bad; } if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst) && ip6->ip6_dst.s6_addr16[1]) { ip6stat.ip6s_badscope++; goto bad; } } if ((m->m_pkthdr.pkt_flags & PKTF_IFAINFO) != 0 && in6_embedded_scope) { if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { ip6->ip6_src.s6_addr16[1] = htons(m->m_pkthdr.src_ifindex); } if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { ip6->ip6_dst.s6_addr16[1] = htons(m->m_pkthdr.dst_ifindex); } } else if (in6_embedded_scope) { if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { ip6->ip6_src.s6_addr16[1] = htons(inifp->if_index); } if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { ip6->ip6_dst.s6_addr16[1] = htons(inifp->if_index); } } /* * Multicast check */ if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { struct in6_multi *in6m = NULL; in6_ifstat_inc_na(inifp, ifs6_in_mcast); /* * See if we belong to the destination multicast group on the * arrival interface. */ in6_multihead_lock_shared(); IN6_LOOKUP_MULTI(&ip6->ip6_dst, inifp, in6m); in6_multihead_lock_done(); if (in6m != NULL) { IN6M_REMREF(in6m); ours = 1; } else if (!nd6_prproxy) { ip6stat.ip6s_notmember++; ip6stat.ip6s_cantforward++; in6_ifstat_inc(inifp, ifs6_in_discard); goto bad; } deliverifp = inifp; /* * record dst address information into mbuf, if we don't have one yet. * note that we are unable to record it, if the address is not listed * as our interface address (e.g. multicast addresses, etc.) */ if (deliverifp != NULL) { struct in6_ifaddr *ia6 = NULL; ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst); if (ia6 != NULL) { (void) ip6_setdstifaddr_info(m, 0, ia6); (void) ip6_setsrcifaddr_info(m, ia6->ia_ifp->if_index, NULL); ifa_remref(&ia6->ia_ifa); } else { (void) ip6_setdstifaddr_info(m, inifp->if_index, NULL); (void) ip6_setsrcifaddr_info(m, inifp->if_index, NULL); } } goto hbhcheck; } else { /* * Unicast check */ ip6_check_if_result_t check_if_result = IP6_CHECK_IF_NONE; check_if_result = ip6_input_check_interface(m, ip6, inifp, &rin6, &deliverifp); ASSERT(check_if_result != IP6_CHECK_IF_NONE); if (check_if_result == IP6_CHECK_IF_OURS) { ours = 1; goto hbhcheck; } else if (check_if_result == IP6_CHECK_IF_DROP) { goto bad; } } /* * Now there is no reason to process the packet if it's not our own * and we're not a router. */ if (!ip6_forwarding) { ip6stat.ip6s_cantforward++; in6_ifstat_inc(inifp, ifs6_in_discard); /* * Raise a kernel event if the packet received on cellular * interface is not intended for local host. * For now limit it to ICMPv6 packets. */ if (inifp->if_type == IFT_CELLULAR && ip6->ip6_nxt == IPPROTO_ICMPV6) { in6_ifstat_inc(inifp, ifs6_cantfoward_icmp6); } goto bad; } hbhcheck: /* * Process Hop-by-Hop options header if it's contained. * m may be modified in ip6_hopopts_input(). * If a JumboPayload option is included, plen will also be modified. */ plen = (u_int32_t)ntohs(ip6->ip6_plen); if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { struct ip6_hbh *hbh; /* * Mark the packet to imply that HBH option has been checked. * This can only be true is the packet came in unfragmented * or if the option is in the first fragment */ m->m_pkthdr.pkt_flags |= PKTF_HBH_CHKED; if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) { #if 0 /* touches NULL pointer */ in6_ifstat_inc(inifp, ifs6_in_discard); #endif goto done; /* m have already been freed */ } /* adjust pointer */ ip6 = mtod(m, struct ip6_hdr *); /* * if the payload length field is 0 and the next header field * indicates Hop-by-Hop Options header, then a Jumbo Payload * option MUST be included. */ if (ip6->ip6_plen == 0 && plen == 0) { /* * Note that if a valid jumbo payload option is * contained, ip6_hopopts_input() must set a valid * (non-zero) payload length to the variable plen. */ ip6stat.ip6s_badoptions++; in6_ifstat_inc(inifp, ifs6_in_discard); in6_ifstat_inc(inifp, ifs6_in_hdrerr); icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, (int)((caddr_t)&ip6->ip6_plen - (caddr_t)ip6)); goto done; } /* ip6_hopopts_input() ensures that mbuf is contiguous */ hbh = (struct ip6_hbh *)(ip6 + 1); nxt = hbh->ip6h_nxt; /* * If we are acting as a router and the packet contains a * router alert option, see if we know the option value. * Currently, we only support the option value for MLD, in which * case we should pass the packet to the multicast routing * daemon. */ if (rtalert != ~0 && ip6_forwarding) { switch (rtalert) { case IP6OPT_RTALERT_MLD: ours = 1; break; default: /* * RFC2711 requires unrecognized values must be * silently ignored. */ break; } } } else { nxt = ip6->ip6_nxt; } /* * Check that the amount of data in the buffers * is as at least much as the IPv6 header would have us expect. * Trim mbufs if longer than we expect. * Drop packet if shorter than we expect. */ if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) { ip6stat.ip6s_tooshort++; in6_ifstat_inc(inifp, ifs6_in_truncated); goto bad; } if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) { ip6_input_adjust(m, ip6, plen, inifp); } /* * Forward if desirable. */ if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { if (!ours && nd6_prproxy) { /* * If this isn't for us, this might be a Neighbor * Solicitation (dst is solicited-node multicast) * against an address in one of the proxied prefixes; * if so, claim the packet and let icmp6_input() * handle the rest. */ ours = nd6_prproxy_isours(m, ip6, NULL, IFSCOPE_NONE); VERIFY(!ours || (m->m_pkthdr.pkt_flags & PKTF_PROXY_DST)); } if (!ours) { goto bad; } } else if (!ours) { /* * The unicast forwarding function might return the packet * if we are proxying prefix(es), and if the packet is an * ICMPv6 packet that has failed the zone checks, but is * targetted towards a proxied address (this is optimized by * way of RTF_PROXY test.) If so, claim the packet as ours * and let icmp6_input() handle the rest. The packet's hop * limit value is kept intact (it's not decremented). This * is for supporting Neighbor Unreachability Detection between * proxied nodes on different links (src is link-local, dst * is target address.) */ if ((m = ip6_forward(m, &rin6, 0)) == NULL) { goto done; } VERIFY(rin6.ro_rt != NULL); VERIFY(m->m_pkthdr.pkt_flags & PKTF_PROXY_DST); deliverifp = rin6.ro_rt->rt_ifp; ours = 1; } ip6 = mtod(m, struct ip6_hdr *); /* * Malicious party may be able to use IPv4 mapped addr to confuse * tcp/udp stack and bypass security checks (act as if it was from * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious. * * For SIIT end node behavior, you may want to disable the check. * However, you will become vulnerable to attacks using IPv4 mapped * source. */ if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) || IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) { ip6stat.ip6s_badscope++; in6_ifstat_inc(inifp, ifs6_in_addrerr); goto bad; } /* * Tell launch routine the next header */ ip6stat.ip6s_delivered++; in6_ifstat_inc_na(deliverifp, ifs6_in_deliver); injectit: nest = 0; /* * Perform IP header alignment fixup again, if needed. Note that * we do it once for the outermost protocol, and we assume each * protocol handler wouldn't mess with the alignment afterwards. */ IP6_HDR_ALIGNMENT_FIXUP(m, inifp, return ); while (nxt != IPPROTO_DONE) { struct ipfilter *filter; int (*pr_input)(struct mbuf **, int *, int); /* * This would imply either IPPROTO_HOPOPTS was not the first * option or it did not come in the first fragment. */ if (nxt == IPPROTO_HOPOPTS && (m->m_pkthdr.pkt_flags & PKTF_HBH_CHKED) == 0) { /* * This implies that HBH option was not contained * in the first fragment */ ip6stat.ip6s_badoptions++; goto bad; } if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { ip6stat.ip6s_toomanyhdr++; goto bad; } /* * protection against faulty packet - there should be * more sanity checks in header chain processing. */ if (m->m_pkthdr.len < off) { ip6stat.ip6s_tooshort++; in6_ifstat_inc(inifp, ifs6_in_truncated); goto bad; } #if IPSEC /* * enforce IPsec policy checking if we are seeing last header. * note that we do not visit this with protocols with pcb layer * code - like udp/tcp/raw ip. */ if ((ipsec_bypass == 0) && (ip6_protox[nxt]->pr_flags & PR_LASTHDR) != 0) { if (ipsec6_in_reject(m, NULL)) { IPSEC_STAT_INCREMENT(ipsec6stat.in_polvio); goto bad; } } #endif /* IPSEC */ /* * Call IP filter */ if (!TAILQ_EMPTY(&ipv6_filters) && !IFNET_IS_INTCOPROC(inifp)) { ipf_ref(); TAILQ_FOREACH(filter, &ipv6_filters, ipf_link) { if (seen == 0) { if ((struct ipfilter *)inject_ipfref == filter) { seen = 1; } } else if (filter->ipf_filter.ipf_input) { errno_t result; result = filter->ipf_filter.ipf_input( filter->ipf_filter.cookie, (mbuf_t *)&m, off, (uint8_t)nxt); if (result == EJUSTRETURN) { ipf_unref(); goto done; } if (result != 0) { ipf_unref(); goto bad; } } } ipf_unref(); } DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL, struct ip6_hdr *, ip6, struct ifnet *, inifp, struct ip *, NULL, struct ip6_hdr *, ip6); if ((pr_input = ip6_protox[nxt]->pr_input) == NULL) { m_freem(m); m = NULL; nxt = IPPROTO_DONE; } else if (!(ip6_protox[nxt]->pr_flags & PR_PROTOLOCK)) { lck_mtx_lock(inet6_domain_mutex); nxt = pr_input(&m, &off, nxt); lck_mtx_unlock(inet6_domain_mutex); } else { nxt = pr_input(&m, &off, nxt); } } done: ROUTE_RELEASE(&rin6); return; bad: m_freem(m); goto done; } void ip6_setsrcifaddr_info(struct mbuf *m, uint32_t src_idx, struct in6_ifaddr *ia6) { VERIFY(m->m_flags & M_PKTHDR); m->m_pkthdr.pkt_ext_flags &= ~PKTF_EXT_OUTPUT_SCOPE; /* * If the source ifaddr is specified, pick up the information * from there; otherwise just grab the passed-in ifindex as the * caller may not have the ifaddr available. */ if (ia6 != NULL) { m->m_pkthdr.pkt_flags |= PKTF_IFAINFO; m->m_pkthdr.src_ifindex = ia6->ia_ifp->if_index; /* See IN6_IFF comments in in6_var.h */ m->m_pkthdr.src_iff = (ia6->ia6_flags & 0xffff); } else { m->m_pkthdr.src_iff = 0; m->m_pkthdr.src_ifindex = (uint16_t)src_idx; if (src_idx != 0) { m->m_pkthdr.pkt_flags |= PKTF_IFAINFO; } } } void ip6_setdstifaddr_info(struct mbuf *m, uint32_t dst_idx, struct in6_ifaddr *ia6) { VERIFY(m->m_flags & M_PKTHDR); m->m_pkthdr.pkt_ext_flags &= ~PKTF_EXT_OUTPUT_SCOPE; /* * If the destination ifaddr is specified, pick up the information * from there; otherwise just grab the passed-in ifindex as the * caller may not have the ifaddr available. */ if (ia6 != NULL) { m->m_pkthdr.pkt_flags |= PKTF_IFAINFO; m->m_pkthdr.dst_ifindex = ia6->ia_ifp->if_index; /* See IN6_IFF comments in in6_var.h */ m->m_pkthdr.dst_iff = (ia6->ia6_flags & 0xffff); } else { m->m_pkthdr.dst_iff = 0; m->m_pkthdr.dst_ifindex = (uint16_t)dst_idx; if (dst_idx != 0) { m->m_pkthdr.pkt_flags |= PKTF_IFAINFO; } } } int ip6_getsrcifaddr_info(struct mbuf *m, uint32_t *src_idx, uint32_t *ia6f) { VERIFY(m->m_flags & M_PKTHDR); if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO)) { return -1; } if (src_idx != NULL) { *src_idx = m->m_pkthdr.src_ifindex; } if (ia6f != NULL) { *ia6f = m->m_pkthdr.src_iff; } return 0; } int ip6_getdstifaddr_info(struct mbuf *m, uint32_t *dst_idx, uint32_t *ia6f) { VERIFY(m->m_flags & M_PKTHDR); if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO)) { return -1; } if (dst_idx != NULL) { *dst_idx = m->m_pkthdr.dst_ifindex; } if (ia6f != NULL) { *ia6f = m->m_pkthdr.dst_iff; } return 0; } uint32_t ip6_input_getsrcifscope(struct mbuf *m) { VERIFY(m->m_flags & M_PKTHDR); if (m->m_pkthdr.rcvif != NULL) { return m->m_pkthdr.rcvif->if_index; } uint32_t src_ifscope = IFSCOPE_NONE; ip6_getsrcifaddr_info(m, &src_ifscope, NULL); return src_ifscope; } uint32_t ip6_input_getdstifscope(struct mbuf *m) { VERIFY(m->m_flags & M_PKTHDR); if (m->m_pkthdr.rcvif != NULL) { return m->m_pkthdr.rcvif->if_index; } uint32_t dst_ifscope = IFSCOPE_NONE; ip6_getdstifaddr_info(m, &dst_ifscope, NULL); return dst_ifscope; } /* * Hop-by-Hop options header processing. If a valid jumbo payload option is * included, the real payload length will be stored in plenp. */ static int ip6_hopopts_input(uint32_t *plenp, uint32_t *rtalertp, struct mbuf **mp, int *offp) { struct mbuf *m = *mp; int off = *offp, hbhlen; struct ip6_hbh *hbh; u_int8_t *opt; /* validation of the length of the header */ IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), return (-1)); hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); hbhlen = (hbh->ip6h_len + 1) << 3; IP6_EXTHDR_CHECK(m, off, hbhlen, return (-1)); hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off); off += hbhlen; hbhlen -= sizeof(struct ip6_hbh); opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh); if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh), hbhlen, rtalertp, plenp) < 0) { return -1; } *offp = off; *mp = m; return 0; } /* * Search header for all Hop-by-hop options and process each option. * This function is separate from ip6_hopopts_input() in order to * handle a case where the sending node itself process its hop-by-hop * options header. In such a case, the function is called from ip6_output(). * * The function assumes that hbh header is located right after the IPv6 header * (RFC2460 p7), opthead is pointer into data content in m, and opthead to * opthead + hbhlen is located in continuous memory region. */ int ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen, u_int32_t *rtalertp, u_int32_t *plenp) { struct ip6_hdr *ip6; int optlen = 0; u_int8_t *opt = opthead; u_int16_t rtalert_val; u_int32_t jumboplen; const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh); for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) { switch (*opt) { case IP6OPT_PAD1: optlen = 1; break; case IP6OPT_PADN: if (hbhlen < IP6OPT_MINLEN) { ip6stat.ip6s_toosmall++; goto bad; } optlen = *(opt + 1) + 2; break; case IP6OPT_ROUTER_ALERT: /* XXX may need check for alignment */ if (hbhlen < IP6OPT_RTALERT_LEN) { ip6stat.ip6s_toosmall++; goto bad; } if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) { /* XXX stat */ icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, (int)(erroff + opt + 1 - opthead)); return -1; } optlen = IP6OPT_RTALERT_LEN; bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2); *rtalertp = ntohs(rtalert_val); break; case IP6OPT_JUMBO: /* XXX may need check for alignment */ if (hbhlen < IP6OPT_JUMBO_LEN) { ip6stat.ip6s_toosmall++; goto bad; } if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) { /* XXX stat */ icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, (int)(erroff + opt + 1 - opthead)); return -1; } optlen = IP6OPT_JUMBO_LEN; /* * IPv6 packets that have non 0 payload length * must not contain a jumbo payload option. */ ip6 = mtod(m, struct ip6_hdr *); if (ip6->ip6_plen) { ip6stat.ip6s_badoptions++; icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, (int)(erroff + opt - opthead)); return -1; } /* * We may see jumbolen in unaligned location, so * we'd need to perform bcopy(). */ bcopy(opt + 2, &jumboplen, sizeof(jumboplen)); jumboplen = (u_int32_t)htonl(jumboplen); #if 1 /* * if there are multiple jumbo payload options, * *plenp will be non-zero and the packet will be * rejected. * the behavior may need some debate in ipngwg - * multiple options does not make sense, however, * there's no explicit mention in specification. */ if (*plenp != 0) { ip6stat.ip6s_badoptions++; icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, (int)(erroff + opt + 2 - opthead)); return -1; } #endif /* * jumbo payload length must be larger than 65535. */ if (jumboplen <= IPV6_MAXPACKET) { ip6stat.ip6s_badoptions++; icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, (int)(erroff + opt + 2 - opthead)); return -1; } *plenp = jumboplen; break; default: /* unknown option */ if (hbhlen < IP6OPT_MINLEN) { ip6stat.ip6s_toosmall++; goto bad; } optlen = ip6_unknown_opt(opt, m, erroff + opt - opthead); if (optlen == -1) { return -1; } optlen += 2; break; } } return 0; bad: m_freem(m); return -1; } /* * Unknown option processing. * The third argument `off' is the offset from the IPv6 header to the option, * which is necessary if the IPv6 header the and option header and IPv6 header * is not continuous in order to return an ICMPv6 error. */ int ip6_unknown_opt(uint8_t *optp, struct mbuf *m, size_t off) { struct ip6_hdr *ip6; switch (IP6OPT_TYPE(*optp)) { case IP6OPT_TYPE_SKIP: /* ignore the option */ return (int)*(optp + 1); case IP6OPT_TYPE_DISCARD: /* silently discard */ m_freem(m); return -1; case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */ ip6stat.ip6s_badoptions++; icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, (int)off); return -1; case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */ ip6stat.ip6s_badoptions++; ip6 = mtod(m, struct ip6_hdr *); if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || (m->m_flags & (M_BCAST | M_MCAST))) { m_freem(m); } else { icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, (int)off); } return -1; } m_freem(m); /* XXX: NOTREACHED */ return -1; } /* * Create the "control" list for this pcb. * These functions will not modify mbuf chain at all. * * With KAME mbuf chain restriction: * The routine will be called from upper layer handlers like tcp6_input(). * Thus the routine assumes that the caller (tcp6_input) have already * called IP6_EXTHDR_CHECK() and all the extension headers are located in the * very first mbuf on the mbuf chain. * * ip6_savecontrol_v4 will handle those options that are possible to be * set on a v4-mapped socket. * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those * options and handle the v6-only ones itself. */ struct mbuf ** ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp, int *v4only) { struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) { struct timeval tv; getmicrotime(&tv); mp = sbcreatecontrol_mbuf((caddr_t)&tv, sizeof(tv), SCM_TIMESTAMP, SOL_SOCKET, mp); if (*mp == NULL) { return NULL; } } if ((inp->inp_socket->so_options & SO_TIMESTAMP_MONOTONIC) != 0) { uint64_t time; time = mach_absolute_time(); mp = sbcreatecontrol_mbuf((caddr_t)&time, sizeof(time), SCM_TIMESTAMP_MONOTONIC, SOL_SOCKET, mp); if (*mp == NULL) { return NULL; } } if ((inp->inp_socket->so_options & SO_TIMESTAMP_CONTINUOUS) != 0) { uint64_t time; time = mach_continuous_time(); mp = sbcreatecontrol_mbuf((caddr_t)&time, sizeof(time), SCM_TIMESTAMP_CONTINUOUS, SOL_SOCKET, mp); if (*mp == NULL) { return NULL; } } if ((inp->inp_socket->so_flags & SOF_RECV_TRAFFIC_CLASS) != 0) { int tc = m_get_traffic_class(m); mp = sbcreatecontrol_mbuf((caddr_t)&tc, sizeof(tc), SO_TRAFFIC_CLASS, SOL_SOCKET, mp); if (*mp == NULL) { return NULL; } } if ((inp->inp_socket->so_flags & SOF_RECV_WAKE_PKT) && (m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT)) { int flag = 1; mp = sbcreatecontrol_mbuf((caddr_t)&flag, sizeof(flag), SO_RECV_WAKE_PKT, SOL_SOCKET, mp); if (*mp == NULL) { return NULL; } } #define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y)) if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) { if (v4only != NULL) { *v4only = 1; } // Send ECN flags for v4-mapped addresses if ((inp->inp_flags & IN6P_TCLASS) != 0) { struct ip *ip_header = mtod(m, struct ip *); int tclass = (int)(ip_header->ip_tos); mp = sbcreatecontrol_mbuf((caddr_t)&tclass, sizeof(tclass), IPV6_TCLASS, IPPROTO_IPV6, mp); if (*mp == NULL) { return NULL; } } // Send IN6P_PKTINFO for v4-mapped address if ((inp->inp_flags & IN6P_PKTINFO) != 0 || SOFLOW_ENABLED(inp->inp_socket)) { struct in6_pktinfo pi6 = { .ipi6_addr = IN6ADDR_V4MAPPED_INIT, .ipi6_ifindex = (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0, }; struct ip *ip_header = mtod(m, struct ip *); bcopy(&ip_header->ip_dst, &pi6.ipi6_addr.s6_addr32[3], sizeof(struct in_addr)); mp = sbcreatecontrol_mbuf((caddr_t)&pi6, sizeof(struct in6_pktinfo), IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6, mp); if (*mp == NULL) { return NULL; } } return mp; } /* RFC 2292 sec. 5 */ if ((inp->inp_flags & IN6P_PKTINFO) != 0 || SOFLOW_ENABLED(inp->inp_socket)) { struct in6_pktinfo pi6; bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr)); in6_clearscope(&pi6.ipi6_addr); /* XXX */ pi6.ipi6_ifindex = (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0; mp = sbcreatecontrol_mbuf((caddr_t)&pi6, sizeof(struct in6_pktinfo), IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6, mp); if (*mp == NULL) { return NULL; } } if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) { int hlim = ip6->ip6_hlim & 0xff; mp = sbcreatecontrol_mbuf((caddr_t)&hlim, sizeof(int), IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT), IPPROTO_IPV6, mp); if (*mp == NULL) { return NULL; } } if (v4only != NULL) { *v4only = 0; } return mp; } int ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp) { struct mbuf **np; struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); int v4only = 0; *mp = NULL; np = ip6_savecontrol_v4(in6p, m, mp, &v4only); if (np == NULL) { goto no_mbufs; } mp = np; if (v4only) { return 0; } if ((in6p->inp_flags & IN6P_TCLASS) != 0) { u_int32_t flowinfo; int tclass; flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK); flowinfo >>= 20; tclass = flowinfo & 0xff; mp = sbcreatecontrol_mbuf((caddr_t)&tclass, sizeof(tclass), IPV6_TCLASS, IPPROTO_IPV6, mp); if (*mp == NULL) { goto no_mbufs; } } /* * IPV6_HOPOPTS socket option. Recall that we required super-user * privilege for the option (see ip6_ctloutput), but it might be too * strict, since there might be some hop-by-hop options which can be * returned to normal user. * See also RFC 2292 section 6 (or RFC 3542 section 8). */ if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) { /* * Check if a hop-by-hop options header is contatined in the * received packet, and if so, store the options as ancillary * data. Note that a hop-by-hop options header must be * just after the IPv6 header, which is assured through the * IPv6 input processing. */ ip6 = mtod(m, struct ip6_hdr *); if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { struct ip6_hbh *hbh; int hbhlen = 0; hbh = (struct ip6_hbh *)(ip6 + 1); hbhlen = (hbh->ip6h_len + 1) << 3; /* * XXX: We copy the whole header even if a * jumbo payload option is included, the option which * is to be removed before returning according to * RFC2292. * Note: this constraint is removed in RFC3542 */ mp = sbcreatecontrol_mbuf((caddr_t)hbh, hbhlen, IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS), IPPROTO_IPV6, mp); if (*mp == NULL) { goto no_mbufs; } } } if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) { int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr); /* * Search for destination options headers or routing * header(s) through the header chain, and stores each * header as ancillary data. * Note that the order of the headers remains in * the chain of ancillary data. */ while (1) { /* is explicit loop prevention necessary? */ struct ip6_ext *ip6e = NULL; int elen; /* * if it is not an extension header, don't try to * pull it from the chain. */ switch (nxt) { case IPPROTO_DSTOPTS: case IPPROTO_ROUTING: case IPPROTO_HOPOPTS: case IPPROTO_AH: /* is it possible? */ break; default: goto loopend; } if (off + sizeof(*ip6e) > m->m_len) { goto loopend; } ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off); if (nxt == IPPROTO_AH) { elen = (ip6e->ip6e_len + 2) << 2; } else { elen = (ip6e->ip6e_len + 1) << 3; } if (off + elen > m->m_len) { goto loopend; } switch (nxt) { case IPPROTO_DSTOPTS: if (!(in6p->inp_flags & IN6P_DSTOPTS)) { break; } mp = sbcreatecontrol_mbuf((caddr_t)ip6e, elen, IS2292(in6p, IPV6_2292DSTOPTS, IPV6_DSTOPTS), IPPROTO_IPV6, mp); if (*mp == NULL) { goto no_mbufs; } break; case IPPROTO_ROUTING: if (!(in6p->inp_flags & IN6P_RTHDR)) { break; } mp = sbcreatecontrol_mbuf((caddr_t)ip6e, elen, IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR), IPPROTO_IPV6, mp); if (*mp == NULL) { goto no_mbufs; } break; case IPPROTO_HOPOPTS: case IPPROTO_AH: /* is it possible? */ break; default: /* * other cases have been filtered in the above. * none will visit this case. here we supply * the code just in case (nxt overwritten or * other cases). */ goto loopend; } /* proceed with the next header. */ off += elen; nxt = ip6e->ip6e_nxt; ip6e = NULL; } loopend: ; } return 0; no_mbufs: ip6stat.ip6s_pktdropcntrl++; /* XXX increment a stat to show the failure */ return ENOBUFS; } #undef IS2292 void ip6_notify_pmtu(struct inpcb *in6p, struct sockaddr_in6 *dst, u_int32_t *mtu) { struct socket *so; struct mbuf *m_mtu; struct ip6_mtuinfo mtuctl; so = in6p->inp_socket; if ((in6p->inp_flags & IN6P_MTU) == 0) { return; } if (mtu == NULL) { return; } if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && SOCK_CHECK_PROTO(so, IPPROTO_TCP)) { return; } if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && !in6_are_addr_equal_scoped(&in6p->in6p_faddr, &dst->sin6_addr, in6p->inp_fifscope, dst->sin6_scope_id)) { return; } bzero(&mtuctl, sizeof(mtuctl)); /* zero-clear for safety */ mtuctl.ip6m_mtu = *mtu; mtuctl.ip6m_addr = *dst; if (!in6_embedded_scope) { mtuctl.ip6m_addr.sin6_scope_id = dst->sin6_scope_id; } if (sa6_recoverscope(&mtuctl.ip6m_addr, TRUE)) { return; } if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl), IPV6_PATHMTU, IPPROTO_IPV6)) == NULL) { return; } if (sbappendaddr(&so->so_rcv, SA(dst), NULL, m_mtu, NULL) == 0) { return; } sorwakeup(so); } /* * Get pointer to the previous header followed by the header * currently processed. * XXX: This function supposes that * M includes all headers, * the next header field and the header length field of each header * are valid, and * the sum of each header length equals to OFF. * Because of these assumptions, this function must be called very * carefully. Moreover, it will not be used in the near future when * we develop `neater' mechanism to process extension headers. */ char * ip6_get_prevhdr(struct mbuf *m, int off) { struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); if (off == sizeof(struct ip6_hdr)) { return (char *)&ip6->ip6_nxt; } else { int len, nxt; struct ip6_ext *ip6e = NULL; nxt = ip6->ip6_nxt; len = sizeof(struct ip6_hdr); while (len < off) { ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len); switch (nxt) { case IPPROTO_FRAGMENT: len += sizeof(struct ip6_frag); break; case IPPROTO_AH: len += (ip6e->ip6e_len + 2) << 2; break; default: len += (ip6e->ip6e_len + 1) << 3; break; } nxt = ip6e->ip6e_nxt; } if (ip6e) { return (char *)&ip6e->ip6e_nxt; } else { return NULL; } } } /* * get next header offset. m will be retained. */ int ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp) { struct ip6_hdr ip6; struct ip6_ext ip6e; struct ip6_frag fh; /* just in case */ VERIFY(m != NULL); if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) { return -1; } switch (proto) { case IPPROTO_IPV6: if (m->m_pkthdr.len < off + sizeof(ip6)) { return -1; } m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6); if (nxtp) { *nxtp = ip6.ip6_nxt; } off += sizeof(ip6); return off; case IPPROTO_FRAGMENT: /* * terminate parsing if it is not the first fragment, * it does not make sense to parse through it. */ if (m->m_pkthdr.len < off + sizeof(fh)) { return -1; } m_copydata(m, off, sizeof(fh), (caddr_t)&fh); /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */ if (fh.ip6f_offlg & IP6F_OFF_MASK) { return -1; } if (nxtp) { *nxtp = fh.ip6f_nxt; } off += sizeof(struct ip6_frag); return off; case IPPROTO_AH: if (m->m_pkthdr.len < off + sizeof(ip6e)) { return -1; } m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); if (nxtp) { *nxtp = ip6e.ip6e_nxt; } off += (ip6e.ip6e_len + 2) << 2; return off; case IPPROTO_HOPOPTS: case IPPROTO_ROUTING: case IPPROTO_DSTOPTS: if (m->m_pkthdr.len < off + sizeof(ip6e)) { return -1; } m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e); if (nxtp) { *nxtp = ip6e.ip6e_nxt; } off += (ip6e.ip6e_len + 1) << 3; return off; case IPPROTO_NONE: case IPPROTO_ESP: case IPPROTO_IPCOMP: /* give up */ return -1; default: return -1; } } /* * get offset for the last header in the chain. m will be kept untainted. */ int ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp) { int newoff; int nxt; if (!nxtp) { nxt = -1; nxtp = &nxt; } while (1) { newoff = ip6_nexthdr(m, off, proto, nxtp); if (newoff < 0) { return off; } else if (newoff < off) { return -1; /* invalid */ } else if (newoff == off) { return newoff; } off = newoff; proto = *nxtp; } } boolean_t ip6_pkt_has_ulp(struct mbuf *m) { int off = 0, nxt = IPPROTO_NONE; off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); if (off < 0 || m->m_pkthdr.len < off) { return FALSE; } switch (nxt) { case IPPROTO_TCP: if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) { return FALSE; } break; case IPPROTO_UDP: if (off + sizeof(struct udphdr) > m->m_pkthdr.len) { return FALSE; } break; case IPPROTO_ICMPV6: if (off + sizeof(uint32_t) > m->m_pkthdr.len) { return FALSE; } break; case IPPROTO_NONE: return TRUE; case IPPROTO_ESP: return TRUE; case IPPROTO_IPCOMP: return TRUE; default: return FALSE; } return TRUE; } struct ip6aux * ip6_addaux(struct mbuf *m) { struct m_tag *tag; /* Check if one is already allocated */ tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_INET6); if (tag == NULL) { /* Allocate a tag */ tag = m_tag_create(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_INET6, sizeof(struct ip6aux), M_DONTWAIT, m); /* Attach it to the mbuf */ if (tag) { m_tag_prepend(m, tag); } } return tag ? (struct ip6aux *)(tag->m_tag_data) : NULL; } struct ip6aux * ip6_findaux(struct mbuf *m) { struct m_tag *tag; tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_INET6); return tag != NULL ? (struct ip6aux *)(tag->m_tag_data) : NULL; } void ip6_delaux(struct mbuf *m) { struct m_tag *tag; tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_INET6); if (tag != NULL) { m_tag_delete(m, tag); } } struct inet6_tag_container { struct m_tag inet6_m_tag; struct ip6aux inet6_ip6a; }; struct m_tag * m_tag_kalloc_inet6(u_int32_t id, u_int16_t type, uint16_t len, int wait) { struct inet6_tag_container *tag_container; struct m_tag *tag = NULL; assert3u(id, ==, KERNEL_MODULE_TAG_ID); assert3u(type, ==, KERNEL_TAG_TYPE_INET6); assert3u(len, ==, sizeof(struct ip6aux)); if (len != sizeof(struct ip6aux)) { return NULL; } tag_container = kalloc_type(struct inet6_tag_container, wait | M_ZERO); if (tag_container != NULL) { tag = &tag_container->inet6_m_tag; assert3p(tag, ==, tag_container); M_TAG_INIT(tag, id, type, len, &tag_container->inet6_ip6a, NULL); } return tag; } void m_tag_kfree_inet6(struct m_tag *tag) { struct inet6_tag_container *tag_container = (struct inet6_tag_container *)tag; assert3u(tag->m_tag_len, ==, sizeof(struct ip6aux)); kfree_type(struct inet6_tag_container, tag_container); } void ip6_register_m_tag(void) { int error; error = m_register_internal_tag_type(KERNEL_TAG_TYPE_INET6, sizeof(struct ip6aux), m_tag_kalloc_inet6, m_tag_kfree_inet6); assert3u(error, ==, 0); } /* * Drain callback */ void ip6_drain(void) { frag6_drain(); /* fragments */ in6_rtqdrain(); /* protocol cloned routes */ nd6_drain(NULL); /* cloned routes: ND6 */ } /* * System control for IP6 */ u_char inet6ctlerrmap[PRC_NCMDS] = { 0, 0, 0, 0, 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, EMSGSIZE, EHOSTUNREACH, 0, 0, 0, 0, 0, 0, ENOPROTOOPT, ECONNREFUSED }; static int sysctl_reset_ip6_input_stats SYSCTL_HANDLER_ARGS { #pragma unused(arg1, arg2) int error, i; i = ip6_input_measure; error = sysctl_handle_int(oidp, &i, 0, req); if (error || req->newptr == USER_ADDR_NULL) { goto done; } /* impose bounds */ if (i < 0 || i > 1) { error = EINVAL; goto done; } if (ip6_input_measure != i && i == 1) { net_perf_initialize(&net_perf, ip6_input_measure_bins); } ip6_input_measure = i; done: return error; } static int sysctl_ip6_input_measure_bins SYSCTL_HANDLER_ARGS { #pragma unused(arg1, arg2) int error; uint64_t i; i = ip6_input_measure_bins; error = sysctl_handle_quad(oidp, &i, 0, req); if (error || req->newptr == USER_ADDR_NULL) { goto done; } /* validate data */ if (!net_perf_validate_bins(i)) { error = EINVAL; goto done; } ip6_input_measure_bins = i; done: return error; } static int sysctl_ip6_input_getperf SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg1, arg2) if (req->oldptr == USER_ADDR_NULL) { req->oldlen = (size_t)sizeof(struct net_perf); } return SYSCTL_OUT(req, &net_perf, MIN(sizeof(net_perf), req->oldlen)); } /* * Initialize IPv6 source address hash table. */ static void in6_ifaddrhashtbl_init(void) { int i, k, p; if (in6_ifaddrhashtbl != NULL) { return; } PE_parse_boot_argn("ina6ddr_nhash", &in6addr_nhash, sizeof(in6addr_nhash)); if (in6addr_nhash == 0) { in6addr_nhash = IN6ADDR_NHASH; } in6_ifaddrhashtbl = zalloc_permanent( in6addr_nhash * sizeof(*in6_ifaddrhashtbl), ZALIGN_PTR); /* * Generate the next largest prime greater than in6addr_nhash. */ k = (in6addr_nhash % 2 == 0) ? in6addr_nhash + 1 : in6addr_nhash + 2; for (;;) { p = 1; for (i = 3; i * i <= k; i += 2) { if (k % i == 0) { p = 0; } } if (p == 1) { break; } k += 2; } in6addr_hashp = k; } static int sysctl_ip6_checkinterface SYSCTL_HANDLER_ARGS { #pragma unused(arg1, arg2) int error, i; i = ip6_checkinterface; error = sysctl_handle_int(oidp, &i, 0, req); if (error || req->newptr == USER_ADDR_NULL) { return error; } switch (i) { case IP6_CHECKINTERFACE_WEAK_ES: case IP6_CHECKINTERFACE_HYBRID_ES: case IP6_CHECKINTERFACE_STRONG_ES: if (ip6_checkinterface != i) { ip6_checkinterface = i; os_log(OS_LOG_DEFAULT, "%s: ip6_checkinterface is now %d\n", __func__, ip6_checkinterface); } break; default: error = EINVAL; break; } return error; }