1d8caf56eSAndrey V. Elsukov /*- 2002cae78SAndrey V. Elsukov * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3002cae78SAndrey V. Elsukov * 4002cae78SAndrey V. Elsukov * Copyright (c) 2015-2019 Yandex LLC 5002cae78SAndrey V. Elsukov * Copyright (c) 2015-2019 Andrey V. Elsukov <ae@FreeBSD.org> 6d8caf56eSAndrey V. Elsukov * 7d8caf56eSAndrey V. Elsukov * Redistribution and use in source and binary forms, with or without 8d8caf56eSAndrey V. Elsukov * modification, are permitted provided that the following conditions 9d8caf56eSAndrey V. Elsukov * are met: 10d8caf56eSAndrey V. Elsukov * 11d8caf56eSAndrey V. Elsukov * 1. Redistributions of source code must retain the above copyright 12d8caf56eSAndrey V. Elsukov * notice, this list of conditions and the following disclaimer. 13d8caf56eSAndrey V. Elsukov * 2. Redistributions in binary form must reproduce the above copyright 14d8caf56eSAndrey V. Elsukov * notice, this list of conditions and the following disclaimer in the 15d8caf56eSAndrey V. Elsukov * documentation and/or other materials provided with the distribution. 16d8caf56eSAndrey V. Elsukov * 17d8caf56eSAndrey V. Elsukov * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18d8caf56eSAndrey V. Elsukov * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19d8caf56eSAndrey V. Elsukov * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20d8caf56eSAndrey V. Elsukov * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21d8caf56eSAndrey V. Elsukov * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22d8caf56eSAndrey V. Elsukov * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23d8caf56eSAndrey V. Elsukov * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24d8caf56eSAndrey V. Elsukov * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25d8caf56eSAndrey V. Elsukov * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26d8caf56eSAndrey V. Elsukov * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27d8caf56eSAndrey V. Elsukov */ 28d8caf56eSAndrey V. Elsukov 29d8caf56eSAndrey V. Elsukov #include <sys/cdefs.h> 30d8caf56eSAndrey V. Elsukov __FBSDID("$FreeBSD$"); 31d8caf56eSAndrey V. Elsukov 32d8caf56eSAndrey V. Elsukov #include <sys/param.h> 33d8caf56eSAndrey V. Elsukov #include <sys/systm.h> 34d8caf56eSAndrey V. Elsukov #include <sys/counter.h> 35d8caf56eSAndrey V. Elsukov #include <sys/errno.h> 36d8caf56eSAndrey V. Elsukov #include <sys/kernel.h> 37d8caf56eSAndrey V. Elsukov #include <sys/lock.h> 38d8caf56eSAndrey V. Elsukov #include <sys/mbuf.h> 39d8caf56eSAndrey V. Elsukov #include <sys/module.h> 40d8caf56eSAndrey V. Elsukov #include <sys/rmlock.h> 41d8caf56eSAndrey V. Elsukov #include <sys/rwlock.h> 42d8caf56eSAndrey V. Elsukov #include <sys/socket.h> 43d8caf56eSAndrey V. Elsukov #include <sys/queue.h> 44d8caf56eSAndrey V. Elsukov 45d8caf56eSAndrey V. Elsukov #include <net/if.h> 46d8caf56eSAndrey V. Elsukov #include <net/if_var.h> 47d8caf56eSAndrey V. Elsukov #include <net/if_pflog.h> 48d8caf56eSAndrey V. Elsukov #include <net/pfil.h> 49d8caf56eSAndrey V. Elsukov #include <net/netisr.h> 50d8caf56eSAndrey V. Elsukov #include <net/route.h> 51d8caf56eSAndrey V. Elsukov 52d8caf56eSAndrey V. Elsukov #include <netinet/in.h> 53c570565fSAndrey V. Elsukov #include <netinet/in_fib.h> 54d8caf56eSAndrey V. Elsukov #include <netinet/ip.h> 55d8caf56eSAndrey V. Elsukov #include <netinet/ip_var.h> 56d8caf56eSAndrey V. Elsukov #include <netinet/ip_fw.h> 57d8caf56eSAndrey V. Elsukov #include <netinet/ip6.h> 58d8caf56eSAndrey V. Elsukov #include <netinet/icmp6.h> 59d8caf56eSAndrey V. Elsukov #include <netinet/ip_icmp.h> 60d8caf56eSAndrey V. Elsukov #include <netinet/tcp.h> 61d8caf56eSAndrey V. Elsukov #include <netinet/udp.h> 62d8caf56eSAndrey V. Elsukov #include <netinet6/in6_var.h> 63c570565fSAndrey V. Elsukov #include <netinet6/in6_fib.h> 64d8caf56eSAndrey V. Elsukov #include <netinet6/ip6_var.h> 65b11efc1eSAndrey V. Elsukov #include <netinet6/ip_fw_nat64.h> 66d8caf56eSAndrey V. Elsukov 67d8caf56eSAndrey V. Elsukov #include <netpfil/pf/pf.h> 68d8caf56eSAndrey V. Elsukov #include <netpfil/ipfw/ip_fw_private.h> 69d8caf56eSAndrey V. Elsukov #include <machine/in_cksum.h> 70d8caf56eSAndrey V. Elsukov 71782360deSAndrey V. Elsukov #include "ip_fw_nat64.h" 72782360deSAndrey V. Elsukov #include "nat64_translate.h" 73782360deSAndrey V. Elsukov 74aa271561SAndrey V. Elsukov 75aa271561SAndrey V. Elsukov typedef int (*nat64_output_t)(struct ifnet *, struct mbuf *, 76aa271561SAndrey V. Elsukov struct sockaddr *, struct nat64_counters *, void *); 77aa271561SAndrey V. Elsukov typedef int (*nat64_output_one_t)(struct mbuf *, struct nat64_counters *, 78aa271561SAndrey V. Elsukov void *); 79aa271561SAndrey V. Elsukov 80aa271561SAndrey V. Elsukov static int nat64_find_route4(struct nhop4_basic *, struct sockaddr_in *, 81aa271561SAndrey V. Elsukov struct mbuf *); 82aa271561SAndrey V. Elsukov static int nat64_find_route6(struct nhop6_basic *, struct sockaddr_in6 *, 83aa271561SAndrey V. Elsukov struct mbuf *); 84aa271561SAndrey V. Elsukov static int nat64_output_one(struct mbuf *, struct nat64_counters *, void *); 85aa271561SAndrey V. Elsukov static int nat64_output(struct ifnet *, struct mbuf *, struct sockaddr *, 86aa271561SAndrey V. Elsukov struct nat64_counters *, void *); 87aa271561SAndrey V. Elsukov static int nat64_direct_output_one(struct mbuf *, struct nat64_counters *, 88aa271561SAndrey V. Elsukov void *); 89aa271561SAndrey V. Elsukov static int nat64_direct_output(struct ifnet *, struct mbuf *, 90aa271561SAndrey V. Elsukov struct sockaddr *, struct nat64_counters *, void *); 91aa271561SAndrey V. Elsukov 92aa271561SAndrey V. Elsukov struct nat64_methods { 93aa271561SAndrey V. Elsukov nat64_output_t output; 94aa271561SAndrey V. Elsukov nat64_output_one_t output_one; 95aa271561SAndrey V. Elsukov }; 96aa271561SAndrey V. Elsukov static const struct nat64_methods nat64_netisr = { 97aa271561SAndrey V. Elsukov .output = nat64_output, 98aa271561SAndrey V. Elsukov .output_one = nat64_output_one 99aa271561SAndrey V. Elsukov }; 100aa271561SAndrey V. Elsukov static const struct nat64_methods nat64_direct = { 101aa271561SAndrey V. Elsukov .output = nat64_direct_output, 102aa271561SAndrey V. Elsukov .output_one = nat64_direct_output_one 103aa271561SAndrey V. Elsukov }; 104aa271561SAndrey V. Elsukov VNET_DEFINE_STATIC(const struct nat64_methods *, nat64out) = &nat64_netisr; 105aa271561SAndrey V. Elsukov #define V_nat64out VNET(nat64out) 106aa271561SAndrey V. Elsukov 107aa271561SAndrey V. Elsukov void 108aa271561SAndrey V. Elsukov nat64_set_output_method(int direct) 109aa271561SAndrey V. Elsukov { 110aa271561SAndrey V. Elsukov 111aa271561SAndrey V. Elsukov V_nat64out = direct != 0 ? &nat64_direct: &nat64_netisr; 112aa271561SAndrey V. Elsukov } 113aa271561SAndrey V. Elsukov 114aa271561SAndrey V. Elsukov int 115aa271561SAndrey V. Elsukov nat64_get_output_method(void) 116aa271561SAndrey V. Elsukov { 117aa271561SAndrey V. Elsukov 118aa271561SAndrey V. Elsukov return (V_nat64out == &nat64_direct ? 1: 0); 119aa271561SAndrey V. Elsukov } 120aa271561SAndrey V. Elsukov 121d8caf56eSAndrey V. Elsukov static void 122d8caf56eSAndrey V. Elsukov nat64_log(struct pfloghdr *logdata, struct mbuf *m, sa_family_t family) 123d8caf56eSAndrey V. Elsukov { 124d8caf56eSAndrey V. Elsukov 125d8caf56eSAndrey V. Elsukov logdata->dir = PF_OUT; 126d8caf56eSAndrey V. Elsukov logdata->af = family; 127d8caf56eSAndrey V. Elsukov ipfw_bpf_mtap2(logdata, PFLOG_HDRLEN, m); 128d8caf56eSAndrey V. Elsukov } 129c570565fSAndrey V. Elsukov 130aa271561SAndrey V. Elsukov static int 131aa271561SAndrey V. Elsukov nat64_direct_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 132782360deSAndrey V. Elsukov struct nat64_counters *stats, void *logdata) 133d8caf56eSAndrey V. Elsukov { 134d8caf56eSAndrey V. Elsukov int error; 135d8caf56eSAndrey V. Elsukov 136d8caf56eSAndrey V. Elsukov if (logdata != NULL) 137d8caf56eSAndrey V. Elsukov nat64_log(logdata, m, dst->sa_family); 138782360deSAndrey V. Elsukov error = (*ifp->if_output)(ifp, m, dst, NULL); 139d8caf56eSAndrey V. Elsukov if (error != 0) 140d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, oerrors); 141d8caf56eSAndrey V. Elsukov return (error); 142d8caf56eSAndrey V. Elsukov } 143d8caf56eSAndrey V. Elsukov 144aa271561SAndrey V. Elsukov static int 145aa271561SAndrey V. Elsukov nat64_direct_output_one(struct mbuf *m, struct nat64_counters *stats, 146aa271561SAndrey V. Elsukov void *logdata) 147d8caf56eSAndrey V. Elsukov { 148c570565fSAndrey V. Elsukov struct nhop6_basic nh6; 149c570565fSAndrey V. Elsukov struct nhop4_basic nh4; 150c570565fSAndrey V. Elsukov struct sockaddr_in6 dst6; 151c570565fSAndrey V. Elsukov struct sockaddr_in dst4; 152d8caf56eSAndrey V. Elsukov struct sockaddr *dst; 153d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6; 154d8caf56eSAndrey V. Elsukov struct ip *ip4; 155c570565fSAndrey V. Elsukov struct ifnet *ifp; 156d8caf56eSAndrey V. Elsukov int error; 157d8caf56eSAndrey V. Elsukov 158d8caf56eSAndrey V. Elsukov ip4 = mtod(m, struct ip *); 159d8caf56eSAndrey V. Elsukov switch (ip4->ip_v) { 160d8caf56eSAndrey V. Elsukov case IPVERSION: 161c570565fSAndrey V. Elsukov dst4.sin_addr = ip4->ip_dst; 162c570565fSAndrey V. Elsukov error = nat64_find_route4(&nh4, &dst4, m); 163c570565fSAndrey V. Elsukov if (error != 0) 164d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, noroute4); 165c570565fSAndrey V. Elsukov else { 166c570565fSAndrey V. Elsukov ifp = nh4.nh_ifp; 167c570565fSAndrey V. Elsukov dst = (struct sockaddr *)&dst4; 168c570565fSAndrey V. Elsukov } 169d8caf56eSAndrey V. Elsukov break; 170d8caf56eSAndrey V. Elsukov case (IPV6_VERSION >> 4): 171c570565fSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 172c570565fSAndrey V. Elsukov dst6.sin6_addr = ip6->ip6_dst; 173c570565fSAndrey V. Elsukov error = nat64_find_route6(&nh6, &dst6, m); 174c570565fSAndrey V. Elsukov if (error != 0) 175d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, noroute6); 176c570565fSAndrey V. Elsukov else { 177c570565fSAndrey V. Elsukov ifp = nh6.nh_ifp; 178c570565fSAndrey V. Elsukov dst = (struct sockaddr *)&dst6; 179c570565fSAndrey V. Elsukov } 180d8caf56eSAndrey V. Elsukov break; 181d8caf56eSAndrey V. Elsukov default: 182d8caf56eSAndrey V. Elsukov m_freem(m); 183d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 184d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to unknown IP version"); 185d8caf56eSAndrey V. Elsukov return (EAFNOSUPPORT); 186d8caf56eSAndrey V. Elsukov } 187c570565fSAndrey V. Elsukov if (error != 0) { 188d8caf56eSAndrey V. Elsukov m_freem(m); 189d8caf56eSAndrey V. Elsukov return (EHOSTUNREACH); 190d8caf56eSAndrey V. Elsukov } 191d8caf56eSAndrey V. Elsukov if (logdata != NULL) 192d8caf56eSAndrey V. Elsukov nat64_log(logdata, m, dst->sa_family); 193c570565fSAndrey V. Elsukov error = (*ifp->if_output)(ifp, m, dst, NULL); 194d8caf56eSAndrey V. Elsukov if (error != 0) 195d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, oerrors); 196d8caf56eSAndrey V. Elsukov return (error); 197d8caf56eSAndrey V. Elsukov } 198aa271561SAndrey V. Elsukov 199aa271561SAndrey V. Elsukov static int 200782360deSAndrey V. Elsukov nat64_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 201782360deSAndrey V. Elsukov struct nat64_counters *stats, void *logdata) 202d8caf56eSAndrey V. Elsukov { 203d8caf56eSAndrey V. Elsukov struct ip *ip4; 204d8caf56eSAndrey V. Elsukov int ret, af; 205d8caf56eSAndrey V. Elsukov 206d8caf56eSAndrey V. Elsukov ip4 = mtod(m, struct ip *); 207d8caf56eSAndrey V. Elsukov switch (ip4->ip_v) { 208d8caf56eSAndrey V. Elsukov case IPVERSION: 209d8caf56eSAndrey V. Elsukov af = AF_INET; 210d8caf56eSAndrey V. Elsukov ret = NETISR_IP; 211d8caf56eSAndrey V. Elsukov break; 212d8caf56eSAndrey V. Elsukov case (IPV6_VERSION >> 4): 213d8caf56eSAndrey V. Elsukov af = AF_INET6; 214d8caf56eSAndrey V. Elsukov ret = NETISR_IPV6; 215d8caf56eSAndrey V. Elsukov break; 216d8caf56eSAndrey V. Elsukov default: 217d8caf56eSAndrey V. Elsukov m_freem(m); 218d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 219d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "unknown IP version"); 220d8caf56eSAndrey V. Elsukov return (EAFNOSUPPORT); 221d8caf56eSAndrey V. Elsukov } 222d8caf56eSAndrey V. Elsukov if (logdata != NULL) 223d8caf56eSAndrey V. Elsukov nat64_log(logdata, m, af); 224d7622795SAndrey V. Elsukov if (m->m_pkthdr.rcvif == NULL) 225d7622795SAndrey V. Elsukov m->m_pkthdr.rcvif = V_loif; 226d8caf56eSAndrey V. Elsukov ret = netisr_queue(ret, m); 227d8caf56eSAndrey V. Elsukov if (ret != 0) 228d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, oerrors); 229d8caf56eSAndrey V. Elsukov return (ret); 230d8caf56eSAndrey V. Elsukov } 231d8caf56eSAndrey V. Elsukov 232aa271561SAndrey V. Elsukov static int 233782360deSAndrey V. Elsukov nat64_output_one(struct mbuf *m, struct nat64_counters *stats, void *logdata) 234d8caf56eSAndrey V. Elsukov { 235d8caf56eSAndrey V. Elsukov 236782360deSAndrey V. Elsukov return (nat64_output(NULL, m, NULL, stats, logdata)); 237d8caf56eSAndrey V. Elsukov } 238d8caf56eSAndrey V. Elsukov 239782360deSAndrey V. Elsukov /* 240782360deSAndrey V. Elsukov * Check the given IPv6 prefix and length according to RFC6052: 241782360deSAndrey V. Elsukov * The prefixes can only have one of the following lengths: 242782360deSAndrey V. Elsukov * 32, 40, 48, 56, 64, or 96 (The Well-Known Prefix is 96 bits long). 243782360deSAndrey V. Elsukov * Returns zero on success, otherwise EINVAL. 244782360deSAndrey V. Elsukov */ 245782360deSAndrey V. Elsukov int 246b11efc1eSAndrey V. Elsukov nat64_check_prefixlen(int length) 247d8caf56eSAndrey V. Elsukov { 248d8caf56eSAndrey V. Elsukov 249782360deSAndrey V. Elsukov switch (length) { 250782360deSAndrey V. Elsukov case 32: 251782360deSAndrey V. Elsukov case 40: 252782360deSAndrey V. Elsukov case 48: 253782360deSAndrey V. Elsukov case 56: 254782360deSAndrey V. Elsukov case 64: 255782360deSAndrey V. Elsukov case 96: 256b11efc1eSAndrey V. Elsukov return (0); 257b11efc1eSAndrey V. Elsukov } 258b11efc1eSAndrey V. Elsukov return (EINVAL); 259b11efc1eSAndrey V. Elsukov } 260b11efc1eSAndrey V. Elsukov 261b11efc1eSAndrey V. Elsukov int 262b11efc1eSAndrey V. Elsukov nat64_check_prefix6(const struct in6_addr *prefix, int length) 263b11efc1eSAndrey V. Elsukov { 264b11efc1eSAndrey V. Elsukov 265b11efc1eSAndrey V. Elsukov if (nat64_check_prefixlen(length) != 0) 266b11efc1eSAndrey V. Elsukov return (EINVAL); 267b11efc1eSAndrey V. Elsukov 268b11efc1eSAndrey V. Elsukov /* Well-known prefix has 96 prefix length */ 269b11efc1eSAndrey V. Elsukov if (IN6_IS_ADDR_WKPFX(prefix) && length != 96) 270b11efc1eSAndrey V. Elsukov return (EINVAL); 271b11efc1eSAndrey V. Elsukov 272782360deSAndrey V. Elsukov /* Bits 64 to 71 must be set to zero */ 273782360deSAndrey V. Elsukov if (prefix->__u6_addr.__u6_addr8[8] != 0) 274782360deSAndrey V. Elsukov return (EINVAL); 275b11efc1eSAndrey V. Elsukov 276782360deSAndrey V. Elsukov /* Some extra checks */ 277782360deSAndrey V. Elsukov if (IN6_IS_ADDR_MULTICAST(prefix) || 278782360deSAndrey V. Elsukov IN6_IS_ADDR_UNSPECIFIED(prefix) || 279782360deSAndrey V. Elsukov IN6_IS_ADDR_LOOPBACK(prefix)) 280782360deSAndrey V. Elsukov return (EINVAL); 281782360deSAndrey V. Elsukov return (0); 282782360deSAndrey V. Elsukov } 283d8caf56eSAndrey V. Elsukov 284782360deSAndrey V. Elsukov int 285782360deSAndrey V. Elsukov nat64_check_private_ip4(const struct nat64_config *cfg, in_addr_t ia) 286d8caf56eSAndrey V. Elsukov { 287d8caf56eSAndrey V. Elsukov 288b11efc1eSAndrey V. Elsukov if (cfg->flags & NAT64_ALLOW_PRIVATE) 289782360deSAndrey V. Elsukov return (0); 290782360deSAndrey V. Elsukov 291782360deSAndrey V. Elsukov /* WKPFX must not be used to represent non-global IPv4 addresses */ 292782360deSAndrey V. Elsukov if (cfg->flags & NAT64_WKPFX) { 293782360deSAndrey V. Elsukov /* IN_PRIVATE */ 294782360deSAndrey V. Elsukov if ((ia & htonl(0xff000000)) == htonl(0x0a000000) || 295782360deSAndrey V. Elsukov (ia & htonl(0xfff00000)) == htonl(0xac100000) || 296782360deSAndrey V. Elsukov (ia & htonl(0xffff0000)) == htonl(0xc0a80000)) 297782360deSAndrey V. Elsukov return (1); 298782360deSAndrey V. Elsukov /* 299782360deSAndrey V. Elsukov * RFC 5735: 300782360deSAndrey V. Elsukov * 192.0.0.0/24 - reserved for IETF protocol assignments 301782360deSAndrey V. Elsukov * 192.88.99.0/24 - for use as 6to4 relay anycast addresses 302782360deSAndrey V. Elsukov * 198.18.0.0/15 - for use in benchmark tests 303782360deSAndrey V. Elsukov * 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24 - for use 304782360deSAndrey V. Elsukov * in documentation and example code 305782360deSAndrey V. Elsukov */ 306782360deSAndrey V. Elsukov if ((ia & htonl(0xffffff00)) == htonl(0xc0000000) || 307782360deSAndrey V. Elsukov (ia & htonl(0xffffff00)) == htonl(0xc0586300) || 308782360deSAndrey V. Elsukov (ia & htonl(0xfffffe00)) == htonl(0xc6120000) || 309782360deSAndrey V. Elsukov (ia & htonl(0xffffff00)) == htonl(0xc0000200) || 310782360deSAndrey V. Elsukov (ia & htonl(0xfffffe00)) == htonl(0xc6336400) || 311782360deSAndrey V. Elsukov (ia & htonl(0xffffff00)) == htonl(0xcb007100)) 312782360deSAndrey V. Elsukov return (1); 313782360deSAndrey V. Elsukov } 314782360deSAndrey V. Elsukov return (0); 315782360deSAndrey V. Elsukov } 316782360deSAndrey V. Elsukov 317b11efc1eSAndrey V. Elsukov /* 318b11efc1eSAndrey V. Elsukov * Embed @ia IPv4 address into @ip6 IPv6 address. 319b11efc1eSAndrey V. Elsukov * Place to embedding determined from prefix length @plen. 320b11efc1eSAndrey V. Elsukov */ 321782360deSAndrey V. Elsukov void 322b11efc1eSAndrey V. Elsukov nat64_embed_ip4(struct in6_addr *ip6, int plen, in_addr_t ia) 323782360deSAndrey V. Elsukov { 324782360deSAndrey V. Elsukov 325b11efc1eSAndrey V. Elsukov switch (plen) { 326d8caf56eSAndrey V. Elsukov case 32: 327d8caf56eSAndrey V. Elsukov case 96: 328b11efc1eSAndrey V. Elsukov ip6->s6_addr32[plen / 32] = ia; 329d8caf56eSAndrey V. Elsukov break; 330d8caf56eSAndrey V. Elsukov case 40: 331d8caf56eSAndrey V. Elsukov case 48: 332d8caf56eSAndrey V. Elsukov case 56: 333b11efc1eSAndrey V. Elsukov /* 334b11efc1eSAndrey V. Elsukov * Preserve prefix bits. 335b11efc1eSAndrey V. Elsukov * Since suffix bits should be zero and reserved for future 336b11efc1eSAndrey V. Elsukov * use, we just overwrite the whole word, where they are. 337b11efc1eSAndrey V. Elsukov */ 338b11efc1eSAndrey V. Elsukov ip6->s6_addr32[1] &= 0xffffffff << (32 - plen % 32); 339d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 340b11efc1eSAndrey V. Elsukov ip6->s6_addr32[1] |= ia >> (plen % 32); 341b11efc1eSAndrey V. Elsukov ip6->s6_addr32[2] = ia << (24 - plen % 32); 342d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 343b11efc1eSAndrey V. Elsukov ip6->s6_addr32[1] |= ia << (plen % 32); 344b11efc1eSAndrey V. Elsukov ip6->s6_addr32[2] = ia >> (24 - plen % 32); 345d8caf56eSAndrey V. Elsukov #endif 346d8caf56eSAndrey V. Elsukov break; 347d8caf56eSAndrey V. Elsukov case 64: 348d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 349d8caf56eSAndrey V. Elsukov ip6->s6_addr32[2] = ia >> 8; 350d8caf56eSAndrey V. Elsukov ip6->s6_addr32[3] = ia << 24; 351d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 352d8caf56eSAndrey V. Elsukov ip6->s6_addr32[2] = ia << 8; 353d8caf56eSAndrey V. Elsukov ip6->s6_addr32[3] = ia >> 24; 354d8caf56eSAndrey V. Elsukov #endif 355d8caf56eSAndrey V. Elsukov break; 356d8caf56eSAndrey V. Elsukov default: 357b11efc1eSAndrey V. Elsukov panic("Wrong plen: %d", plen); 358d8caf56eSAndrey V. Elsukov }; 359b11efc1eSAndrey V. Elsukov /* 360b11efc1eSAndrey V. Elsukov * Bits 64 to 71 of the address are reserved for compatibility 361b11efc1eSAndrey V. Elsukov * with the host identifier format defined in the IPv6 addressing 362b11efc1eSAndrey V. Elsukov * architecture [RFC4291]. These bits MUST be set to zero. 363b11efc1eSAndrey V. Elsukov */ 364d8caf56eSAndrey V. Elsukov ip6->s6_addr8[8] = 0; 365d8caf56eSAndrey V. Elsukov } 366d8caf56eSAndrey V. Elsukov 367782360deSAndrey V. Elsukov in_addr_t 368b11efc1eSAndrey V. Elsukov nat64_extract_ip4(const struct in6_addr *ip6, int plen) 369d8caf56eSAndrey V. Elsukov { 370d8caf56eSAndrey V. Elsukov in_addr_t ia; 371d8caf56eSAndrey V. Elsukov 372d8caf56eSAndrey V. Elsukov /* 373d8caf56eSAndrey V. Elsukov * According to RFC 6052 p2.2: 374d8caf56eSAndrey V. Elsukov * IPv4-embedded IPv6 addresses are composed of a variable-length 375d8caf56eSAndrey V. Elsukov * prefix, the embedded IPv4 address, and a variable length suffix. 376d8caf56eSAndrey V. Elsukov * The suffix bits are reserved for future extensions and SHOULD 377d8caf56eSAndrey V. Elsukov * be set to zero. 378d8caf56eSAndrey V. Elsukov */ 379b11efc1eSAndrey V. Elsukov switch (plen) { 380d8caf56eSAndrey V. Elsukov case 32: 381d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || ip6->s6_addr32[2] != 0) 382d8caf56eSAndrey V. Elsukov goto badip6; 383d8caf56eSAndrey V. Elsukov break; 384d8caf56eSAndrey V. Elsukov case 40: 385d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || 386d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[2] & htonl(0xff00ffff)) != 0) 387d8caf56eSAndrey V. Elsukov goto badip6; 388d8caf56eSAndrey V. Elsukov break; 389d8caf56eSAndrey V. Elsukov case 48: 390d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || 391d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[2] & htonl(0xff0000ff)) != 0) 392d8caf56eSAndrey V. Elsukov goto badip6; 393d8caf56eSAndrey V. Elsukov break; 394d8caf56eSAndrey V. Elsukov case 56: 395d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || ip6->s6_addr8[8] != 0) 396d8caf56eSAndrey V. Elsukov goto badip6; 397d8caf56eSAndrey V. Elsukov break; 398d8caf56eSAndrey V. Elsukov case 64: 399d8caf56eSAndrey V. Elsukov if (ip6->s6_addr8[8] != 0 || 400d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[3] & htonl(0x00ffffff)) != 0) 401d8caf56eSAndrey V. Elsukov goto badip6; 402d8caf56eSAndrey V. Elsukov }; 403b11efc1eSAndrey V. Elsukov switch (plen) { 404d8caf56eSAndrey V. Elsukov case 32: 405d8caf56eSAndrey V. Elsukov case 96: 406b11efc1eSAndrey V. Elsukov ia = ip6->s6_addr32[plen / 32]; 407d8caf56eSAndrey V. Elsukov break; 408d8caf56eSAndrey V. Elsukov case 40: 409d8caf56eSAndrey V. Elsukov case 48: 410d8caf56eSAndrey V. Elsukov case 56: 411d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 412b11efc1eSAndrey V. Elsukov ia = (ip6->s6_addr32[1] << (plen % 32)) | 413b11efc1eSAndrey V. Elsukov (ip6->s6_addr32[2] >> (24 - plen % 32)); 414d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 415b11efc1eSAndrey V. Elsukov ia = (ip6->s6_addr32[1] >> (plen % 32)) | 416b11efc1eSAndrey V. Elsukov (ip6->s6_addr32[2] << (24 - plen % 32)); 417d8caf56eSAndrey V. Elsukov #endif 418d8caf56eSAndrey V. Elsukov break; 419d8caf56eSAndrey V. Elsukov case 64: 420d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 421d8caf56eSAndrey V. Elsukov ia = (ip6->s6_addr32[2] << 8) | (ip6->s6_addr32[3] >> 24); 422d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 423d8caf56eSAndrey V. Elsukov ia = (ip6->s6_addr32[2] >> 8) | (ip6->s6_addr32[3] << 24); 424d8caf56eSAndrey V. Elsukov #endif 425d8caf56eSAndrey V. Elsukov break; 426d8caf56eSAndrey V. Elsukov default: 427d8caf56eSAndrey V. Elsukov return (0); 428d8caf56eSAndrey V. Elsukov }; 429b11efc1eSAndrey V. Elsukov if (nat64_check_ip4(ia) == 0) 430d8caf56eSAndrey V. Elsukov return (ia); 431b11efc1eSAndrey V. Elsukov 432782360deSAndrey V. Elsukov DPRINTF(DP_GENERIC | DP_DROPS, 433782360deSAndrey V. Elsukov "invalid destination address: %08x", ia); 434d8caf56eSAndrey V. Elsukov return (0); 435d8caf56eSAndrey V. Elsukov badip6: 436782360deSAndrey V. Elsukov DPRINTF(DP_GENERIC | DP_DROPS, "invalid IPv4-embedded IPv6 address"); 437d8caf56eSAndrey V. Elsukov return (0); 438d8caf56eSAndrey V. Elsukov } 439d8caf56eSAndrey V. Elsukov 440d8caf56eSAndrey V. Elsukov /* 441d8caf56eSAndrey V. Elsukov * According to RFC 1624 the equation for incremental checksum update is: 442d8caf56eSAndrey V. Elsukov * HC' = ~(~HC + ~m + m') -- [Eqn. 3] 443d8caf56eSAndrey V. Elsukov * HC' = HC - ~m - m' -- [Eqn. 4] 444d8caf56eSAndrey V. Elsukov * So, when we are replacing IPv4 addresses to IPv6, we 445d8caf56eSAndrey V. Elsukov * can assume, that new bytes previously were zeros, and vise versa - 446d8caf56eSAndrey V. Elsukov * when we replacing IPv6 addresses to IPv4, now unused bytes become 447d8caf56eSAndrey V. Elsukov * zeros. The payload length in pseudo header has bigger size, but one 448d8caf56eSAndrey V. Elsukov * half of it should be zero. Using the equation 4 we get: 449d8caf56eSAndrey V. Elsukov * HC' = HC - (~m0 + m0') -- m0 is first changed word 450d8caf56eSAndrey V. Elsukov * HC' = (HC - (~m0 + m0')) - (~m1 + m1') -- m1 is second changed word 451d8caf56eSAndrey V. Elsukov * HC' = HC - ~m0 - m0' - ~m1 - m1' - ... = 452d8caf56eSAndrey V. Elsukov * = HC - sum(~m[i] + m'[i]) 453d8caf56eSAndrey V. Elsukov * 454d8caf56eSAndrey V. Elsukov * The function result should be used as follows: 455d8caf56eSAndrey V. Elsukov * IPv6 to IPv4: HC' = cksum_add(HC, result) 456d8caf56eSAndrey V. Elsukov * IPv4 to IPv6: HC' = cksum_add(HC, ~result) 457d8caf56eSAndrey V. Elsukov */ 458b11efc1eSAndrey V. Elsukov static uint16_t 459d8caf56eSAndrey V. Elsukov nat64_cksum_convert(struct ip6_hdr *ip6, struct ip *ip) 460d8caf56eSAndrey V. Elsukov { 461d8caf56eSAndrey V. Elsukov uint32_t sum; 462d8caf56eSAndrey V. Elsukov uint16_t *p; 463d8caf56eSAndrey V. Elsukov 464d8caf56eSAndrey V. Elsukov sum = ~ip->ip_src.s_addr >> 16; 465d8caf56eSAndrey V. Elsukov sum += ~ip->ip_src.s_addr & 0xffff; 466d8caf56eSAndrey V. Elsukov sum += ~ip->ip_dst.s_addr >> 16; 467d8caf56eSAndrey V. Elsukov sum += ~ip->ip_dst.s_addr & 0xffff; 468d8caf56eSAndrey V. Elsukov 469d8caf56eSAndrey V. Elsukov for (p = (uint16_t *)&ip6->ip6_src; 470d8caf56eSAndrey V. Elsukov p < (uint16_t *)(&ip6->ip6_src + 2); p++) 471d8caf56eSAndrey V. Elsukov sum += *p; 472d8caf56eSAndrey V. Elsukov 473d8caf56eSAndrey V. Elsukov while (sum >> 16) 474d8caf56eSAndrey V. Elsukov sum = (sum & 0xffff) + (sum >> 16); 475d8caf56eSAndrey V. Elsukov return (sum); 476d8caf56eSAndrey V. Elsukov } 477d8caf56eSAndrey V. Elsukov 478b11efc1eSAndrey V. Elsukov static void 479d8caf56eSAndrey V. Elsukov nat64_init_ip4hdr(const struct ip6_hdr *ip6, const struct ip6_frag *frag, 480d8caf56eSAndrey V. Elsukov uint16_t plen, uint8_t proto, struct ip *ip) 481d8caf56eSAndrey V. Elsukov { 482d8caf56eSAndrey V. Elsukov 483d8caf56eSAndrey V. Elsukov /* assume addresses are already initialized */ 484d8caf56eSAndrey V. Elsukov ip->ip_v = IPVERSION; 485d8caf56eSAndrey V. Elsukov ip->ip_hl = sizeof(*ip) >> 2; 486d8caf56eSAndrey V. Elsukov ip->ip_tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 487d8caf56eSAndrey V. Elsukov ip->ip_len = htons(sizeof(*ip) + plen); 488d8caf56eSAndrey V. Elsukov ip->ip_ttl = ip6->ip6_hlim; 489aa271561SAndrey V. Elsukov /* Forwarding code will decrement TTL for netisr based output. */ 490aa271561SAndrey V. Elsukov if (V_nat64out == &nat64_direct) 491aa271561SAndrey V. Elsukov ip->ip_ttl -= IPV6_HLIMDEC; 492d8caf56eSAndrey V. Elsukov ip->ip_sum = 0; 493d8caf56eSAndrey V. Elsukov ip->ip_p = (proto == IPPROTO_ICMPV6) ? IPPROTO_ICMP: proto; 494d8caf56eSAndrey V. Elsukov ip_fillid(ip); 495d8caf56eSAndrey V. Elsukov if (frag != NULL) { 496d8caf56eSAndrey V. Elsukov ip->ip_off = htons(ntohs(frag->ip6f_offlg) >> 3); 497d8caf56eSAndrey V. Elsukov if (frag->ip6f_offlg & IP6F_MORE_FRAG) 498d8caf56eSAndrey V. Elsukov ip->ip_off |= htons(IP_MF); 499d8caf56eSAndrey V. Elsukov } else { 500d8caf56eSAndrey V. Elsukov ip->ip_off = htons(IP_DF); 501d8caf56eSAndrey V. Elsukov } 502d8caf56eSAndrey V. Elsukov ip->ip_sum = in_cksum_hdr(ip); 503d8caf56eSAndrey V. Elsukov } 504d8caf56eSAndrey V. Elsukov 505d8caf56eSAndrey V. Elsukov #define FRAGSZ(mtu) ((mtu) - sizeof(struct ip6_hdr) - sizeof(struct ip6_frag)) 506c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 507782360deSAndrey V. Elsukov nat64_fragment6(struct nat64_counters *stats, struct ip6_hdr *ip6, 508782360deSAndrey V. Elsukov struct mbufq *mq, struct mbuf *m, uint32_t mtu, uint16_t ip_id, 509782360deSAndrey V. Elsukov uint16_t ip_off) 510d8caf56eSAndrey V. Elsukov { 511d8caf56eSAndrey V. Elsukov struct ip6_frag ip6f; 512d8caf56eSAndrey V. Elsukov struct mbuf *n; 513d8caf56eSAndrey V. Elsukov uint16_t hlen, len, offset; 514d8caf56eSAndrey V. Elsukov int plen; 515d8caf56eSAndrey V. Elsukov 516d8caf56eSAndrey V. Elsukov plen = ntohs(ip6->ip6_plen); 517d8caf56eSAndrey V. Elsukov hlen = sizeof(struct ip6_hdr); 518d8caf56eSAndrey V. Elsukov 519d8caf56eSAndrey V. Elsukov /* Fragmentation isn't needed */ 520d8caf56eSAndrey V. Elsukov if (ip_off == 0 && plen <= mtu - hlen) { 521d8caf56eSAndrey V. Elsukov M_PREPEND(m, hlen, M_NOWAIT); 522d8caf56eSAndrey V. Elsukov if (m == NULL) { 523d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 524d8caf56eSAndrey V. Elsukov return (ENOMEM); 525d8caf56eSAndrey V. Elsukov } 526d8caf56eSAndrey V. Elsukov bcopy(ip6, mtod(m, void *), hlen); 527d8caf56eSAndrey V. Elsukov if (mbufq_enqueue(mq, m) != 0) { 528d8caf56eSAndrey V. Elsukov m_freem(m); 529d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 530d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to mbufq overflow"); 531d8caf56eSAndrey V. Elsukov return (ENOBUFS); 532d8caf56eSAndrey V. Elsukov } 533d8caf56eSAndrey V. Elsukov return (0); 534d8caf56eSAndrey V. Elsukov } 535d8caf56eSAndrey V. Elsukov 536d8caf56eSAndrey V. Elsukov hlen += sizeof(struct ip6_frag); 537d8caf56eSAndrey V. Elsukov ip6f.ip6f_reserved = 0; 538d8caf56eSAndrey V. Elsukov ip6f.ip6f_nxt = ip6->ip6_nxt; 539d8caf56eSAndrey V. Elsukov ip6->ip6_nxt = IPPROTO_FRAGMENT; 540d8caf56eSAndrey V. Elsukov if (ip_off != 0) { 541d8caf56eSAndrey V. Elsukov /* 542d8caf56eSAndrey V. Elsukov * We have got an IPv4 fragment. 543d8caf56eSAndrey V. Elsukov * Use offset value and ip_id from original fragment. 544d8caf56eSAndrey V. Elsukov */ 545d8caf56eSAndrey V. Elsukov ip6f.ip6f_ident = htonl(ntohs(ip_id)); 546d8caf56eSAndrey V. Elsukov offset = (ntohs(ip_off) & IP_OFFMASK) << 3; 547d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, ifrags); 548d8caf56eSAndrey V. Elsukov } else { 549d8caf56eSAndrey V. Elsukov /* The packet size exceeds interface MTU */ 550d8caf56eSAndrey V. Elsukov ip6f.ip6f_ident = htonl(ip6_randomid()); 551d8caf56eSAndrey V. Elsukov offset = 0; /* First fragment*/ 552d8caf56eSAndrey V. Elsukov } 553d8caf56eSAndrey V. Elsukov while (plen > 0 && m != NULL) { 554d8caf56eSAndrey V. Elsukov n = NULL; 555d8caf56eSAndrey V. Elsukov len = FRAGSZ(mtu) & ~7; 556d8caf56eSAndrey V. Elsukov if (len > plen) 557d8caf56eSAndrey V. Elsukov len = plen; 558d8caf56eSAndrey V. Elsukov ip6->ip6_plen = htons(len + sizeof(ip6f)); 559d8caf56eSAndrey V. Elsukov ip6f.ip6f_offlg = ntohs(offset); 560d8caf56eSAndrey V. Elsukov if (len < plen || (ip_off & htons(IP_MF)) != 0) 561d8caf56eSAndrey V. Elsukov ip6f.ip6f_offlg |= IP6F_MORE_FRAG; 562d8caf56eSAndrey V. Elsukov offset += len; 563d8caf56eSAndrey V. Elsukov plen -= len; 564d8caf56eSAndrey V. Elsukov if (plen > 0) { 565d8caf56eSAndrey V. Elsukov n = m_split(m, len, M_NOWAIT); 566d8caf56eSAndrey V. Elsukov if (n == NULL) 567d8caf56eSAndrey V. Elsukov goto fail; 568d8caf56eSAndrey V. Elsukov } 569d8caf56eSAndrey V. Elsukov M_PREPEND(m, hlen, M_NOWAIT); 570d8caf56eSAndrey V. Elsukov if (m == NULL) 571d8caf56eSAndrey V. Elsukov goto fail; 572d8caf56eSAndrey V. Elsukov bcopy(ip6, mtod(m, void *), sizeof(struct ip6_hdr)); 573d8caf56eSAndrey V. Elsukov bcopy(&ip6f, mtodo(m, sizeof(struct ip6_hdr)), 574d8caf56eSAndrey V. Elsukov sizeof(struct ip6_frag)); 575d8caf56eSAndrey V. Elsukov if (mbufq_enqueue(mq, m) != 0) 576d8caf56eSAndrey V. Elsukov goto fail; 577d8caf56eSAndrey V. Elsukov m = n; 578d8caf56eSAndrey V. Elsukov } 579d8caf56eSAndrey V. Elsukov NAT64STAT_ADD(stats, ofrags, mbufq_len(mq)); 580d8caf56eSAndrey V. Elsukov return (0); 581d8caf56eSAndrey V. Elsukov fail: 582d8caf56eSAndrey V. Elsukov if (m != NULL) 583d8caf56eSAndrey V. Elsukov m_freem(m); 584d8caf56eSAndrey V. Elsukov if (n != NULL) 585d8caf56eSAndrey V. Elsukov m_freem(n); 586d8caf56eSAndrey V. Elsukov mbufq_drain(mq); 587d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 588d8caf56eSAndrey V. Elsukov return (ENOMEM); 589d8caf56eSAndrey V. Elsukov } 590d8caf56eSAndrey V. Elsukov 591c570565fSAndrey V. Elsukov static NAT64NOINLINE int 592c570565fSAndrey V. Elsukov nat64_find_route6(struct nhop6_basic *pnh, struct sockaddr_in6 *dst, 593c570565fSAndrey V. Elsukov struct mbuf *m) 594d8caf56eSAndrey V. Elsukov { 595d8caf56eSAndrey V. Elsukov 596c570565fSAndrey V. Elsukov if (fib6_lookup_nh_basic(M_GETFIB(m), &dst->sin6_addr, 0, 0, 0, 597c570565fSAndrey V. Elsukov pnh) != 0) 598c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 599c570565fSAndrey V. Elsukov if (pnh->nh_flags & (NHF_BLACKHOLE | NHF_REJECT)) 600c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 601c570565fSAndrey V. Elsukov /* 602c570565fSAndrey V. Elsukov * XXX: we need to use destination address with embedded scope 603c570565fSAndrey V. Elsukov * zone id, because LLTABLE uses such form of addresses for lookup. 604c570565fSAndrey V. Elsukov */ 605d8caf56eSAndrey V. Elsukov dst->sin6_family = AF_INET6; 606d8caf56eSAndrey V. Elsukov dst->sin6_len = sizeof(*dst); 607c570565fSAndrey V. Elsukov dst->sin6_addr = pnh->nh_addr; 608c570565fSAndrey V. Elsukov if (IN6_IS_SCOPE_LINKLOCAL(&dst->sin6_addr)) 609c570565fSAndrey V. Elsukov dst->sin6_addr.s6_addr16[1] = 610c570565fSAndrey V. Elsukov htons(pnh->nh_ifp->if_index & 0xffff); 611c570565fSAndrey V. Elsukov dst->sin6_port = 0; 612c570565fSAndrey V. Elsukov dst->sin6_scope_id = 0; 613c570565fSAndrey V. Elsukov dst->sin6_flowinfo = 0; 614c570565fSAndrey V. Elsukov 615c570565fSAndrey V. Elsukov return (0); 616d8caf56eSAndrey V. Elsukov } 617d8caf56eSAndrey V. Elsukov 618d8caf56eSAndrey V. Elsukov #define NAT64_ICMP6_PLEN 64 619c402a01bSAndrey V. Elsukov static NAT64NOINLINE void 620d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(struct mbuf *m, uint8_t type, uint8_t code, uint32_t mtu, 621782360deSAndrey V. Elsukov struct nat64_counters *stats, void *logdata) 622d8caf56eSAndrey V. Elsukov { 623d8caf56eSAndrey V. Elsukov struct icmp6_hdr *icmp6; 624d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6, *oip6; 625d8caf56eSAndrey V. Elsukov struct mbuf *n; 626d8caf56eSAndrey V. Elsukov int len, plen; 627d8caf56eSAndrey V. Elsukov 628d8caf56eSAndrey V. Elsukov len = 0; 629d8caf56eSAndrey V. Elsukov plen = nat64_getlasthdr(m, &len); 630d8caf56eSAndrey V. Elsukov if (plen < 0) { 631d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "mbuf isn't contigious"); 632d8caf56eSAndrey V. Elsukov goto freeit; 633d8caf56eSAndrey V. Elsukov } 634d8caf56eSAndrey V. Elsukov /* 635d8caf56eSAndrey V. Elsukov * Do not send ICMPv6 in reply to ICMPv6 errors. 636d8caf56eSAndrey V. Elsukov */ 637d8caf56eSAndrey V. Elsukov if (plen == IPPROTO_ICMPV6) { 638d8caf56eSAndrey V. Elsukov if (m->m_len < len + sizeof(*icmp6)) { 639d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "mbuf isn't contigious"); 640d8caf56eSAndrey V. Elsukov goto freeit; 641d8caf56eSAndrey V. Elsukov } 642d8caf56eSAndrey V. Elsukov icmp6 = mtodo(m, len); 643d8caf56eSAndrey V. Elsukov if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST || 644d8caf56eSAndrey V. Elsukov icmp6->icmp6_type == ND_REDIRECT) { 645d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "do not send ICMPv6 in reply to " 646d8caf56eSAndrey V. Elsukov "ICMPv6 errors"); 647d8caf56eSAndrey V. Elsukov goto freeit; 648d8caf56eSAndrey V. Elsukov } 649d8caf56eSAndrey V. Elsukov } 650d8caf56eSAndrey V. Elsukov /* 651d8caf56eSAndrey V. Elsukov if (icmp6_ratelimit(&ip6->ip6_src, type, code)) 652d8caf56eSAndrey V. Elsukov goto freeit; 653d8caf56eSAndrey V. Elsukov */ 654d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 655d8caf56eSAndrey V. Elsukov switch (type) { 656d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH: 657d8caf56eSAndrey V. Elsukov case ICMP6_PACKET_TOO_BIG: 658d8caf56eSAndrey V. Elsukov case ICMP6_TIME_EXCEEDED: 659d8caf56eSAndrey V. Elsukov case ICMP6_PARAM_PROB: 660d8caf56eSAndrey V. Elsukov break; 661d8caf56eSAndrey V. Elsukov default: 662d8caf56eSAndrey V. Elsukov goto freeit; 663d8caf56eSAndrey V. Elsukov } 664d8caf56eSAndrey V. Elsukov /* Calculate length of ICMPv6 payload */ 665d8caf56eSAndrey V. Elsukov len = (m->m_pkthdr.len > NAT64_ICMP6_PLEN) ? NAT64_ICMP6_PLEN: 666d8caf56eSAndrey V. Elsukov m->m_pkthdr.len; 667d8caf56eSAndrey V. Elsukov 668d8caf56eSAndrey V. Elsukov /* Create new ICMPv6 datagram */ 669d8caf56eSAndrey V. Elsukov plen = len + sizeof(struct icmp6_hdr); 670d8caf56eSAndrey V. Elsukov n = m_get2(sizeof(struct ip6_hdr) + plen + max_hdr, M_NOWAIT, 671d8caf56eSAndrey V. Elsukov MT_HEADER, M_PKTHDR); 672d8caf56eSAndrey V. Elsukov if (n == NULL) { 673d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 674d8caf56eSAndrey V. Elsukov m_freem(m); 675d8caf56eSAndrey V. Elsukov return; 676d8caf56eSAndrey V. Elsukov } 677d8caf56eSAndrey V. Elsukov /* 678d8caf56eSAndrey V. Elsukov * Move pkthdr from original mbuf. We should have initialized some 679d8caf56eSAndrey V. Elsukov * fields, because we can reinject this mbuf to netisr and it will 680d8caf56eSAndrey V. Elsukov * go trough input path (it requires at least rcvif should be set). 681d8caf56eSAndrey V. Elsukov * Also do M_ALIGN() to reduce chances of need to allocate new mbuf 682d8caf56eSAndrey V. Elsukov * in the chain, when we will do M_PREPEND() or make some type of 683d8caf56eSAndrey V. Elsukov * tunneling. 684d8caf56eSAndrey V. Elsukov */ 685d8caf56eSAndrey V. Elsukov m_move_pkthdr(n, m); 686d8caf56eSAndrey V. Elsukov M_ALIGN(n, sizeof(struct ip6_hdr) + plen + max_hdr); 687d8caf56eSAndrey V. Elsukov 688d8caf56eSAndrey V. Elsukov n->m_len = n->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 689d8caf56eSAndrey V. Elsukov oip6 = mtod(n, struct ip6_hdr *); 690d8caf56eSAndrey V. Elsukov oip6->ip6_src = ip6->ip6_dst; 691d8caf56eSAndrey V. Elsukov oip6->ip6_dst = ip6->ip6_src; 692d8caf56eSAndrey V. Elsukov oip6->ip6_nxt = IPPROTO_ICMPV6; 693d8caf56eSAndrey V. Elsukov oip6->ip6_flow = 0; 694d8caf56eSAndrey V. Elsukov oip6->ip6_vfc |= IPV6_VERSION; 695d8caf56eSAndrey V. Elsukov oip6->ip6_hlim = V_ip6_defhlim; 696d8caf56eSAndrey V. Elsukov oip6->ip6_plen = htons(plen); 697d8caf56eSAndrey V. Elsukov 698d8caf56eSAndrey V. Elsukov icmp6 = mtodo(n, sizeof(struct ip6_hdr)); 699d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = 0; 700d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = type; 701d8caf56eSAndrey V. Elsukov icmp6->icmp6_code = code; 702d8caf56eSAndrey V. Elsukov icmp6->icmp6_mtu = htonl(mtu); 703d8caf56eSAndrey V. Elsukov 704d8caf56eSAndrey V. Elsukov m_copydata(m, 0, len, mtodo(n, sizeof(struct ip6_hdr) + 705d8caf56eSAndrey V. Elsukov sizeof(struct icmp6_hdr))); 706d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = in6_cksum(n, IPPROTO_ICMPV6, 707d8caf56eSAndrey V. Elsukov sizeof(struct ip6_hdr), plen); 708d8caf56eSAndrey V. Elsukov m_freem(m); 709aa271561SAndrey V. Elsukov V_nat64out->output_one(n, stats, logdata); 710d8caf56eSAndrey V. Elsukov return; 711d8caf56eSAndrey V. Elsukov freeit: 712d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 713d8caf56eSAndrey V. Elsukov m_freem(m); 714d8caf56eSAndrey V. Elsukov } 715d8caf56eSAndrey V. Elsukov 716c570565fSAndrey V. Elsukov static NAT64NOINLINE int 717c570565fSAndrey V. Elsukov nat64_find_route4(struct nhop4_basic *pnh, struct sockaddr_in *dst, 718c570565fSAndrey V. Elsukov struct mbuf *m) 719d8caf56eSAndrey V. Elsukov { 720d8caf56eSAndrey V. Elsukov 721c570565fSAndrey V. Elsukov if (fib4_lookup_nh_basic(M_GETFIB(m), dst->sin_addr, 0, 0, pnh) != 0) 722c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 723c570565fSAndrey V. Elsukov if (pnh->nh_flags & (NHF_BLACKHOLE | NHF_BROADCAST | NHF_REJECT)) 724c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 725c570565fSAndrey V. Elsukov 726d8caf56eSAndrey V. Elsukov dst->sin_family = AF_INET; 727d8caf56eSAndrey V. Elsukov dst->sin_len = sizeof(*dst); 728c570565fSAndrey V. Elsukov dst->sin_addr = pnh->nh_addr; 729c570565fSAndrey V. Elsukov dst->sin_port = 0; 730c570565fSAndrey V. Elsukov return (0); 731d8caf56eSAndrey V. Elsukov } 732d8caf56eSAndrey V. Elsukov 733d8caf56eSAndrey V. Elsukov #define NAT64_ICMP_PLEN 64 734c402a01bSAndrey V. Elsukov static NAT64NOINLINE void 735d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(struct mbuf *m, uint8_t type, 736782360deSAndrey V. Elsukov uint8_t code, uint16_t mtu, struct nat64_counters *stats, void *logdata) 737d8caf56eSAndrey V. Elsukov { 738d8caf56eSAndrey V. Elsukov struct icmp *icmp; 739d8caf56eSAndrey V. Elsukov struct ip *ip, *oip; 740d8caf56eSAndrey V. Elsukov struct mbuf *n; 741d8caf56eSAndrey V. Elsukov int len, plen; 742d8caf56eSAndrey V. Elsukov 743d8caf56eSAndrey V. Elsukov ip = mtod(m, struct ip *); 744d8caf56eSAndrey V. Elsukov /* Do not send ICMP error if packet is not the first fragment */ 745d8caf56eSAndrey V. Elsukov if (ip->ip_off & ~ntohs(IP_MF|IP_DF)) { 746d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "not first fragment"); 747d8caf56eSAndrey V. Elsukov goto freeit; 748d8caf56eSAndrey V. Elsukov } 749d8caf56eSAndrey V. Elsukov /* Do not send ICMP in reply to ICMP errors */ 750d8caf56eSAndrey V. Elsukov if (ip->ip_p == IPPROTO_ICMP) { 751d8caf56eSAndrey V. Elsukov if (m->m_len < (ip->ip_hl << 2)) { 752d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "mbuf isn't contigious"); 753d8caf56eSAndrey V. Elsukov goto freeit; 754d8caf56eSAndrey V. Elsukov } 755d8caf56eSAndrey V. Elsukov icmp = mtodo(m, ip->ip_hl << 2); 756d8caf56eSAndrey V. Elsukov if (!ICMP_INFOTYPE(icmp->icmp_type)) { 757d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "do not send ICMP in reply to " 758d8caf56eSAndrey V. Elsukov "ICMP errors"); 759d8caf56eSAndrey V. Elsukov goto freeit; 760d8caf56eSAndrey V. Elsukov } 761d8caf56eSAndrey V. Elsukov } 762d8caf56eSAndrey V. Elsukov switch (type) { 763d8caf56eSAndrey V. Elsukov case ICMP_UNREACH: 764d8caf56eSAndrey V. Elsukov case ICMP_TIMXCEED: 765d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB: 766d8caf56eSAndrey V. Elsukov break; 767d8caf56eSAndrey V. Elsukov default: 768d8caf56eSAndrey V. Elsukov goto freeit; 769d8caf56eSAndrey V. Elsukov } 770d8caf56eSAndrey V. Elsukov /* Calculate length of ICMP payload */ 771d8caf56eSAndrey V. Elsukov len = (m->m_pkthdr.len > NAT64_ICMP_PLEN) ? (ip->ip_hl << 2) + 8: 772d8caf56eSAndrey V. Elsukov m->m_pkthdr.len; 773d8caf56eSAndrey V. Elsukov 774d8caf56eSAndrey V. Elsukov /* Create new ICMPv4 datagram */ 775d8caf56eSAndrey V. Elsukov plen = len + sizeof(struct icmphdr) + sizeof(uint32_t); 776d8caf56eSAndrey V. Elsukov n = m_get2(sizeof(struct ip) + plen + max_hdr, M_NOWAIT, 777d8caf56eSAndrey V. Elsukov MT_HEADER, M_PKTHDR); 778d8caf56eSAndrey V. Elsukov if (n == NULL) { 779d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 780d8caf56eSAndrey V. Elsukov m_freem(m); 781d8caf56eSAndrey V. Elsukov return; 782d8caf56eSAndrey V. Elsukov } 783d8caf56eSAndrey V. Elsukov m_move_pkthdr(n, m); 784d8caf56eSAndrey V. Elsukov M_ALIGN(n, sizeof(struct ip) + plen + max_hdr); 785d8caf56eSAndrey V. Elsukov 786d8caf56eSAndrey V. Elsukov n->m_len = n->m_pkthdr.len = sizeof(struct ip) + plen; 787d8caf56eSAndrey V. Elsukov oip = mtod(n, struct ip *); 788d8caf56eSAndrey V. Elsukov oip->ip_v = IPVERSION; 789d8caf56eSAndrey V. Elsukov oip->ip_hl = sizeof(struct ip) >> 2; 790d8caf56eSAndrey V. Elsukov oip->ip_tos = 0; 791d8caf56eSAndrey V. Elsukov oip->ip_len = htons(n->m_pkthdr.len); 792d8caf56eSAndrey V. Elsukov oip->ip_ttl = V_ip_defttl; 793d8caf56eSAndrey V. Elsukov oip->ip_p = IPPROTO_ICMP; 794d8caf56eSAndrey V. Elsukov ip_fillid(oip); 795d8caf56eSAndrey V. Elsukov oip->ip_off = htons(IP_DF); 796d8caf56eSAndrey V. Elsukov oip->ip_src = ip->ip_dst; 797d8caf56eSAndrey V. Elsukov oip->ip_dst = ip->ip_src; 798d8caf56eSAndrey V. Elsukov oip->ip_sum = 0; 799d8caf56eSAndrey V. Elsukov oip->ip_sum = in_cksum_hdr(oip); 800d8caf56eSAndrey V. Elsukov 801d8caf56eSAndrey V. Elsukov icmp = mtodo(n, sizeof(struct ip)); 802d8caf56eSAndrey V. Elsukov icmp->icmp_type = type; 803d8caf56eSAndrey V. Elsukov icmp->icmp_code = code; 804d8caf56eSAndrey V. Elsukov icmp->icmp_cksum = 0; 805d8caf56eSAndrey V. Elsukov icmp->icmp_pmvoid = 0; 806d8caf56eSAndrey V. Elsukov icmp->icmp_nextmtu = htons(mtu); 807d8caf56eSAndrey V. Elsukov m_copydata(m, 0, len, mtodo(n, sizeof(struct ip) + 808d8caf56eSAndrey V. Elsukov sizeof(struct icmphdr) + sizeof(uint32_t))); 809d8caf56eSAndrey V. Elsukov icmp->icmp_cksum = in_cksum_skip(n, sizeof(struct ip) + plen, 810d8caf56eSAndrey V. Elsukov sizeof(struct ip)); 811d8caf56eSAndrey V. Elsukov m_freem(m); 812aa271561SAndrey V. Elsukov V_nat64out->output_one(n, stats, logdata); 813d8caf56eSAndrey V. Elsukov return; 814d8caf56eSAndrey V. Elsukov freeit: 815d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 816d8caf56eSAndrey V. Elsukov m_freem(m); 817d8caf56eSAndrey V. Elsukov } 818d8caf56eSAndrey V. Elsukov 819d8caf56eSAndrey V. Elsukov /* Translate ICMP echo request/reply into ICMPv6 */ 820d8caf56eSAndrey V. Elsukov static void 821d8caf56eSAndrey V. Elsukov nat64_icmp_handle_echo(struct ip6_hdr *ip6, struct icmp6_hdr *icmp6, 822d8caf56eSAndrey V. Elsukov uint16_t id, uint8_t type) 823d8caf56eSAndrey V. Elsukov { 824d8caf56eSAndrey V. Elsukov uint16_t old; 825d8caf56eSAndrey V. Elsukov 826d8caf56eSAndrey V. Elsukov old = *(uint16_t *)icmp6; /* save type+code in one word */ 827d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = type; 828d8caf56eSAndrey V. Elsukov /* Reflect ICMPv6 -> ICMPv4 type translation in the cksum */ 829d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = cksum_adjust(icmp6->icmp6_cksum, 830d8caf56eSAndrey V. Elsukov old, *(uint16_t *)icmp6); 831d8caf56eSAndrey V. Elsukov if (id != 0) { 832d8caf56eSAndrey V. Elsukov old = icmp6->icmp6_id; 833d8caf56eSAndrey V. Elsukov icmp6->icmp6_id = id; 834d8caf56eSAndrey V. Elsukov /* Reflect ICMP id translation in the cksum */ 835d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = cksum_adjust(icmp6->icmp6_cksum, 836d8caf56eSAndrey V. Elsukov old, id); 837d8caf56eSAndrey V. Elsukov } 838d8caf56eSAndrey V. Elsukov /* Reflect IPv6 pseudo header in the cksum */ 839d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = ~in6_cksum_pseudo(ip6, ntohs(ip6->ip6_plen), 840d8caf56eSAndrey V. Elsukov IPPROTO_ICMPV6, ~icmp6->icmp6_cksum); 841d8caf56eSAndrey V. Elsukov } 842d8caf56eSAndrey V. Elsukov 843c402a01bSAndrey V. Elsukov static NAT64NOINLINE struct mbuf * 844d8caf56eSAndrey V. Elsukov nat64_icmp_translate(struct mbuf *m, struct ip6_hdr *ip6, uint16_t icmpid, 845782360deSAndrey V. Elsukov int offset, struct nat64_config *cfg) 846d8caf56eSAndrey V. Elsukov { 847d8caf56eSAndrey V. Elsukov struct ip ip; 848d8caf56eSAndrey V. Elsukov struct icmp *icmp; 849d8caf56eSAndrey V. Elsukov struct tcphdr *tcp; 850d8caf56eSAndrey V. Elsukov struct udphdr *udp; 851d8caf56eSAndrey V. Elsukov struct ip6_hdr *eip6; 852d8caf56eSAndrey V. Elsukov struct mbuf *n; 853d8caf56eSAndrey V. Elsukov uint32_t mtu; 854d8caf56eSAndrey V. Elsukov int len, hlen, plen; 855d8caf56eSAndrey V. Elsukov uint8_t type, code; 856d8caf56eSAndrey V. Elsukov 857d8caf56eSAndrey V. Elsukov if (m->m_len < offset + ICMP_MINLEN) 858d8caf56eSAndrey V. Elsukov m = m_pullup(m, offset + ICMP_MINLEN); 859d8caf56eSAndrey V. Elsukov if (m == NULL) { 860782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, nomem); 861d8caf56eSAndrey V. Elsukov return (m); 862d8caf56eSAndrey V. Elsukov } 863d8caf56eSAndrey V. Elsukov mtu = 0; 864d8caf56eSAndrey V. Elsukov icmp = mtodo(m, offset); 865d8caf56eSAndrey V. Elsukov /* RFC 7915 p4.2 */ 866d8caf56eSAndrey V. Elsukov switch (icmp->icmp_type) { 867d8caf56eSAndrey V. Elsukov case ICMP_ECHOREPLY: 868d8caf56eSAndrey V. Elsukov type = ICMP6_ECHO_REPLY; 869d8caf56eSAndrey V. Elsukov code = 0; 870d8caf56eSAndrey V. Elsukov break; 871d8caf56eSAndrey V. Elsukov case ICMP_UNREACH: 872d8caf56eSAndrey V. Elsukov type = ICMP6_DST_UNREACH; 873d8caf56eSAndrey V. Elsukov switch (icmp->icmp_code) { 874d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NET: 875d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_HOST: 876d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_SRCFAIL: 877d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NET_UNKNOWN: 878d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_HOST_UNKNOWN: 879d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_TOSNET: 880d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_TOSHOST: 881d8caf56eSAndrey V. Elsukov code = ICMP6_DST_UNREACH_NOROUTE; 882d8caf56eSAndrey V. Elsukov break; 883d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_PROTOCOL: 884d8caf56eSAndrey V. Elsukov type = ICMP6_PARAM_PROB; 885d8caf56eSAndrey V. Elsukov code = ICMP6_PARAMPROB_NEXTHEADER; 886d8caf56eSAndrey V. Elsukov break; 887d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_PORT: 888d8caf56eSAndrey V. Elsukov code = ICMP6_DST_UNREACH_NOPORT; 889d8caf56eSAndrey V. Elsukov break; 890d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NEEDFRAG: 891d8caf56eSAndrey V. Elsukov type = ICMP6_PACKET_TOO_BIG; 892d8caf56eSAndrey V. Elsukov code = 0; 893d8caf56eSAndrey V. Elsukov /* XXX: needs an additional look */ 894d8caf56eSAndrey V. Elsukov mtu = max(IPV6_MMTU, ntohs(icmp->icmp_nextmtu) + 20); 895d8caf56eSAndrey V. Elsukov break; 896d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NET_PROHIB: 897d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_HOST_PROHIB: 898d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_FILTER_PROHIB: 899d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_PRECEDENCE_CUTOFF: 900d8caf56eSAndrey V. Elsukov code = ICMP6_DST_UNREACH_ADMIN; 901d8caf56eSAndrey V. Elsukov break; 902d8caf56eSAndrey V. Elsukov default: 903d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d, code %d", 904d8caf56eSAndrey V. Elsukov icmp->icmp_type, icmp->icmp_code); 905d8caf56eSAndrey V. Elsukov goto freeit; 906d8caf56eSAndrey V. Elsukov } 907d8caf56eSAndrey V. Elsukov break; 908d8caf56eSAndrey V. Elsukov case ICMP_TIMXCEED: 909d8caf56eSAndrey V. Elsukov type = ICMP6_TIME_EXCEEDED; 910d8caf56eSAndrey V. Elsukov code = icmp->icmp_code; 911d8caf56eSAndrey V. Elsukov break; 912d8caf56eSAndrey V. Elsukov case ICMP_ECHO: 913d8caf56eSAndrey V. Elsukov type = ICMP6_ECHO_REQUEST; 914d8caf56eSAndrey V. Elsukov code = 0; 915d8caf56eSAndrey V. Elsukov break; 916d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB: 917d8caf56eSAndrey V. Elsukov type = ICMP6_PARAM_PROB; 918d8caf56eSAndrey V. Elsukov switch (icmp->icmp_code) { 919d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB_ERRATPTR: 920d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB_LENGTH: 921d8caf56eSAndrey V. Elsukov code = ICMP6_PARAMPROB_HEADER; 922d8caf56eSAndrey V. Elsukov switch (icmp->icmp_pptr) { 923d8caf56eSAndrey V. Elsukov case 0: /* Version/IHL */ 924d8caf56eSAndrey V. Elsukov case 1: /* Type Of Service */ 925d8caf56eSAndrey V. Elsukov mtu = icmp->icmp_pptr; 926d8caf56eSAndrey V. Elsukov break; 927d8caf56eSAndrey V. Elsukov case 2: /* Total Length */ 928d8caf56eSAndrey V. Elsukov case 3: mtu = 4; /* Payload Length */ 929d8caf56eSAndrey V. Elsukov break; 930d8caf56eSAndrey V. Elsukov case 8: /* Time to Live */ 931d8caf56eSAndrey V. Elsukov mtu = 7; /* Hop Limit */ 932d8caf56eSAndrey V. Elsukov break; 933d8caf56eSAndrey V. Elsukov case 9: /* Protocol */ 934d8caf56eSAndrey V. Elsukov mtu = 6; /* Next Header */ 935d8caf56eSAndrey V. Elsukov break; 936d8caf56eSAndrey V. Elsukov case 12: /* Source address */ 937d8caf56eSAndrey V. Elsukov case 13: 938d8caf56eSAndrey V. Elsukov case 14: 939d8caf56eSAndrey V. Elsukov case 15: 940d8caf56eSAndrey V. Elsukov mtu = 8; 941d8caf56eSAndrey V. Elsukov break; 942d8caf56eSAndrey V. Elsukov case 16: /* Destination address */ 943d8caf56eSAndrey V. Elsukov case 17: 944d8caf56eSAndrey V. Elsukov case 18: 945d8caf56eSAndrey V. Elsukov case 19: 946d8caf56eSAndrey V. Elsukov mtu = 24; 947d8caf56eSAndrey V. Elsukov break; 948d8caf56eSAndrey V. Elsukov default: /* Silently drop */ 949d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d," 950d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp->icmp_type, 951d8caf56eSAndrey V. Elsukov icmp->icmp_code, icmp->icmp_pptr); 952d8caf56eSAndrey V. Elsukov goto freeit; 953d8caf56eSAndrey V. Elsukov } 954d8caf56eSAndrey V. Elsukov break; 955d8caf56eSAndrey V. Elsukov default: 956d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d," 957d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp->icmp_type, 958d8caf56eSAndrey V. Elsukov icmp->icmp_code, icmp->icmp_pptr); 959d8caf56eSAndrey V. Elsukov goto freeit; 960d8caf56eSAndrey V. Elsukov } 961d8caf56eSAndrey V. Elsukov break; 962d8caf56eSAndrey V. Elsukov default: 963d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d, code %d", 964d8caf56eSAndrey V. Elsukov icmp->icmp_type, icmp->icmp_code); 965d8caf56eSAndrey V. Elsukov goto freeit; 966d8caf56eSAndrey V. Elsukov } 967d8caf56eSAndrey V. Elsukov /* 968d8caf56eSAndrey V. Elsukov * For echo request/reply we can use original payload, 969d8caf56eSAndrey V. Elsukov * but we need adjust icmp_cksum, because ICMPv6 cksum covers 970d8caf56eSAndrey V. Elsukov * IPv6 pseudo header and ICMPv6 types differs from ICMPv4. 971d8caf56eSAndrey V. Elsukov */ 972d8caf56eSAndrey V. Elsukov if (type == ICMP6_ECHO_REQUEST || type == ICMP6_ECHO_REPLY) { 973d8caf56eSAndrey V. Elsukov nat64_icmp_handle_echo(ip6, ICMP6(icmp), icmpid, type); 974d8caf56eSAndrey V. Elsukov return (m); 975d8caf56eSAndrey V. Elsukov } 976d8caf56eSAndrey V. Elsukov /* 977d8caf56eSAndrey V. Elsukov * For other types of ICMP messages we need to translate inner 978d8caf56eSAndrey V. Elsukov * IPv4 header to IPv6 header. 979d8caf56eSAndrey V. Elsukov * Assume ICMP src is the same as payload dst 980d8caf56eSAndrey V. Elsukov * E.g. we have ( GWsrc1 , NATIP1 ) in outer header 981d8caf56eSAndrey V. Elsukov * and ( NATIP1, Hostdst1 ) in ICMP copy header. 982d8caf56eSAndrey V. Elsukov * In that case, we already have map for NATIP1 and GWsrc1. 983d8caf56eSAndrey V. Elsukov * The only thing we need is to copy IPv6 map prefix to 984d8caf56eSAndrey V. Elsukov * Hostdst1. 985d8caf56eSAndrey V. Elsukov */ 986d8caf56eSAndrey V. Elsukov hlen = offset + ICMP_MINLEN; 987d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + sizeof(struct ip) + ICMP_MINLEN) { 988d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Message is too short %d", 989d8caf56eSAndrey V. Elsukov m->m_pkthdr.len); 990d8caf56eSAndrey V. Elsukov goto freeit; 991d8caf56eSAndrey V. Elsukov } 992d8caf56eSAndrey V. Elsukov m_copydata(m, hlen, sizeof(struct ip), (char *)&ip); 993d8caf56eSAndrey V. Elsukov if (ip.ip_v != IPVERSION) { 994d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Wrong IP version %d", ip.ip_v); 995d8caf56eSAndrey V. Elsukov goto freeit; 996d8caf56eSAndrey V. Elsukov } 997d8caf56eSAndrey V. Elsukov hlen += ip.ip_hl << 2; /* Skip inner IP header */ 998d8caf56eSAndrey V. Elsukov if (nat64_check_ip4(ip.ip_src.s_addr) != 0 || 999d8caf56eSAndrey V. Elsukov nat64_check_ip4(ip.ip_dst.s_addr) != 0 || 1000782360deSAndrey V. Elsukov nat64_check_private_ip4(cfg, ip.ip_src.s_addr) != 0 || 1001782360deSAndrey V. Elsukov nat64_check_private_ip4(cfg, ip.ip_dst.s_addr) != 0) { 1002d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "IP addresses checks failed %04x -> %04x", 1003d8caf56eSAndrey V. Elsukov ntohl(ip.ip_src.s_addr), ntohl(ip.ip_dst.s_addr)); 1004d8caf56eSAndrey V. Elsukov goto freeit; 1005d8caf56eSAndrey V. Elsukov } 1006d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + ICMP_MINLEN) { 1007d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Message is too short %d", 1008d8caf56eSAndrey V. Elsukov m->m_pkthdr.len); 1009d8caf56eSAndrey V. Elsukov goto freeit; 1010d8caf56eSAndrey V. Elsukov } 1011d8caf56eSAndrey V. Elsukov #if 0 1012d8caf56eSAndrey V. Elsukov /* 1013d8caf56eSAndrey V. Elsukov * Check that inner source matches the outer destination. 1014d8caf56eSAndrey V. Elsukov * XXX: We need some method to convert IPv4 into IPv6 address here, 1015d8caf56eSAndrey V. Elsukov * and compare IPv6 addresses. 1016d8caf56eSAndrey V. Elsukov */ 1017d8caf56eSAndrey V. Elsukov if (ip.ip_src.s_addr != nat64_get_ip4(&ip6->ip6_dst)) { 1018d8caf56eSAndrey V. Elsukov DPRINTF(DP_GENERIC, "Inner source doesn't match destination ", 1019d8caf56eSAndrey V. Elsukov "%04x vs %04x", ip.ip_src.s_addr, 1020d8caf56eSAndrey V. Elsukov nat64_get_ip4(&ip6->ip6_dst)); 1021d8caf56eSAndrey V. Elsukov goto freeit; 1022d8caf56eSAndrey V. Elsukov } 1023d8caf56eSAndrey V. Elsukov #endif 1024d8caf56eSAndrey V. Elsukov /* 1025d8caf56eSAndrey V. Elsukov * Create new mbuf for ICMPv6 datagram. 1026d8caf56eSAndrey V. Elsukov * NOTE: len is data length just after inner IP header. 1027d8caf56eSAndrey V. Elsukov */ 1028d8caf56eSAndrey V. Elsukov len = m->m_pkthdr.len - hlen; 1029d8caf56eSAndrey V. Elsukov if (sizeof(struct ip6_hdr) + 1030d8caf56eSAndrey V. Elsukov sizeof(struct icmp6_hdr) + len > NAT64_ICMP6_PLEN) 1031d8caf56eSAndrey V. Elsukov len = NAT64_ICMP6_PLEN - sizeof(struct icmp6_hdr) - 1032d8caf56eSAndrey V. Elsukov sizeof(struct ip6_hdr); 1033d8caf56eSAndrey V. Elsukov plen = sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr) + len; 1034d8caf56eSAndrey V. Elsukov n = m_get2(offset + plen + max_hdr, M_NOWAIT, MT_HEADER, M_PKTHDR); 1035d8caf56eSAndrey V. Elsukov if (n == NULL) { 1036782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, nomem); 1037d8caf56eSAndrey V. Elsukov m_freem(m); 1038d8caf56eSAndrey V. Elsukov return (NULL); 1039d8caf56eSAndrey V. Elsukov } 1040d8caf56eSAndrey V. Elsukov m_move_pkthdr(n, m); 1041d8caf56eSAndrey V. Elsukov M_ALIGN(n, offset + plen + max_hdr); 1042d8caf56eSAndrey V. Elsukov n->m_len = n->m_pkthdr.len = offset + plen; 1043d8caf56eSAndrey V. Elsukov /* Adjust ip6_plen in outer header */ 1044d8caf56eSAndrey V. Elsukov ip6->ip6_plen = htons(plen); 1045d8caf56eSAndrey V. Elsukov /* Construct new inner IPv6 header */ 1046d8caf56eSAndrey V. Elsukov eip6 = mtodo(n, offset + sizeof(struct icmp6_hdr)); 1047d8caf56eSAndrey V. Elsukov eip6->ip6_src = ip6->ip6_dst; 1048b11efc1eSAndrey V. Elsukov 1049b11efc1eSAndrey V. Elsukov /* Use the same prefix that we have in outer header */ 1050d8caf56eSAndrey V. Elsukov eip6->ip6_dst = ip6->ip6_src; 1051b11efc1eSAndrey V. Elsukov MPASS(cfg->flags & NAT64_PLATPFX); 1052b11efc1eSAndrey V. Elsukov nat64_embed_ip4(&eip6->ip6_dst, cfg->plat_plen, ip.ip_dst.s_addr); 1053d8caf56eSAndrey V. Elsukov 1054d8caf56eSAndrey V. Elsukov eip6->ip6_flow = htonl(ip.ip_tos << 20); 1055d8caf56eSAndrey V. Elsukov eip6->ip6_vfc |= IPV6_VERSION; 1056d8caf56eSAndrey V. Elsukov eip6->ip6_hlim = ip.ip_ttl; 1057d8caf56eSAndrey V. Elsukov eip6->ip6_plen = htons(ntohs(ip.ip_len) - (ip.ip_hl << 2)); 1058d8caf56eSAndrey V. Elsukov eip6->ip6_nxt = (ip.ip_p == IPPROTO_ICMP) ? IPPROTO_ICMPV6: ip.ip_p; 1059d8caf56eSAndrey V. Elsukov m_copydata(m, hlen, len, (char *)(eip6 + 1)); 1060d8caf56eSAndrey V. Elsukov /* 1061d8caf56eSAndrey V. Elsukov * We need to translate source port in the inner ULP header, 1062d8caf56eSAndrey V. Elsukov * and adjust ULP checksum. 1063d8caf56eSAndrey V. Elsukov */ 1064d8caf56eSAndrey V. Elsukov switch (ip.ip_p) { 1065d8caf56eSAndrey V. Elsukov case IPPROTO_TCP: 1066d8caf56eSAndrey V. Elsukov if (len < offsetof(struct tcphdr, th_sum)) 1067d8caf56eSAndrey V. Elsukov break; 1068d8caf56eSAndrey V. Elsukov tcp = TCP(eip6 + 1); 1069d8caf56eSAndrey V. Elsukov if (icmpid != 0) { 1070d8caf56eSAndrey V. Elsukov tcp->th_sum = cksum_adjust(tcp->th_sum, 1071d8caf56eSAndrey V. Elsukov tcp->th_sport, icmpid); 1072d8caf56eSAndrey V. Elsukov tcp->th_sport = icmpid; 1073d8caf56eSAndrey V. Elsukov } 1074d8caf56eSAndrey V. Elsukov tcp->th_sum = cksum_add(tcp->th_sum, 1075d8caf56eSAndrey V. Elsukov ~nat64_cksum_convert(eip6, &ip)); 1076d8caf56eSAndrey V. Elsukov break; 1077d8caf56eSAndrey V. Elsukov case IPPROTO_UDP: 1078d8caf56eSAndrey V. Elsukov if (len < offsetof(struct udphdr, uh_sum)) 1079d8caf56eSAndrey V. Elsukov break; 1080d8caf56eSAndrey V. Elsukov udp = UDP(eip6 + 1); 1081d8caf56eSAndrey V. Elsukov if (icmpid != 0) { 1082d8caf56eSAndrey V. Elsukov udp->uh_sum = cksum_adjust(udp->uh_sum, 1083d8caf56eSAndrey V. Elsukov udp->uh_sport, icmpid); 1084d8caf56eSAndrey V. Elsukov udp->uh_sport = icmpid; 1085d8caf56eSAndrey V. Elsukov } 1086d8caf56eSAndrey V. Elsukov udp->uh_sum = cksum_add(udp->uh_sum, 1087d8caf56eSAndrey V. Elsukov ~nat64_cksum_convert(eip6, &ip)); 1088d8caf56eSAndrey V. Elsukov break; 1089d8caf56eSAndrey V. Elsukov case IPPROTO_ICMP: 1090d8caf56eSAndrey V. Elsukov /* 1091d8caf56eSAndrey V. Elsukov * Check if this is an ICMP error message for echo request 1092d8caf56eSAndrey V. Elsukov * that we sent. I.e. ULP in the data containing invoking 1093d8caf56eSAndrey V. Elsukov * packet is IPPROTO_ICMP and its type is ICMP_ECHO. 1094d8caf56eSAndrey V. Elsukov */ 1095d8caf56eSAndrey V. Elsukov icmp = (struct icmp *)(eip6 + 1); 1096d8caf56eSAndrey V. Elsukov if (icmp->icmp_type != ICMP_ECHO) { 1097d8caf56eSAndrey V. Elsukov m_freem(n); 1098d8caf56eSAndrey V. Elsukov goto freeit; 1099d8caf56eSAndrey V. Elsukov } 1100d8caf56eSAndrey V. Elsukov /* 1101d8caf56eSAndrey V. Elsukov * For our client this original datagram should looks 1102d8caf56eSAndrey V. Elsukov * like it was ICMPv6 datagram with type ICMP6_ECHO_REQUEST. 1103d8caf56eSAndrey V. Elsukov * Thus we need adjust icmp_cksum and convert type from 1104d8caf56eSAndrey V. Elsukov * ICMP_ECHO to ICMP6_ECHO_REQUEST. 1105d8caf56eSAndrey V. Elsukov */ 1106d8caf56eSAndrey V. Elsukov nat64_icmp_handle_echo(eip6, ICMP6(icmp), icmpid, 1107d8caf56eSAndrey V. Elsukov ICMP6_ECHO_REQUEST); 1108d8caf56eSAndrey V. Elsukov } 1109d8caf56eSAndrey V. Elsukov m_freem(m); 1110d8caf56eSAndrey V. Elsukov /* Convert ICMPv4 into ICMPv6 header */ 1111d8caf56eSAndrey V. Elsukov icmp = mtodo(n, offset); 1112d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_type = type; 1113d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_code = code; 1114d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_mtu = htonl(mtu); 1115d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_cksum = 0; 1116d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_cksum = cksum_add( 1117d8caf56eSAndrey V. Elsukov ~in6_cksum_pseudo(ip6, plen, IPPROTO_ICMPV6, 0), 1118d8caf56eSAndrey V. Elsukov in_cksum_skip(n, n->m_pkthdr.len, offset)); 1119d8caf56eSAndrey V. Elsukov return (n); 1120d8caf56eSAndrey V. Elsukov freeit: 1121d8caf56eSAndrey V. Elsukov m_freem(m); 1122782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1123d8caf56eSAndrey V. Elsukov return (NULL); 1124d8caf56eSAndrey V. Elsukov } 1125d8caf56eSAndrey V. Elsukov 1126d8caf56eSAndrey V. Elsukov int 1127d8caf56eSAndrey V. Elsukov nat64_getlasthdr(struct mbuf *m, int *offset) 1128d8caf56eSAndrey V. Elsukov { 1129d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6; 1130d8caf56eSAndrey V. Elsukov struct ip6_hbh *hbh; 1131d8caf56eSAndrey V. Elsukov int proto, hlen; 1132d8caf56eSAndrey V. Elsukov 1133d8caf56eSAndrey V. Elsukov if (offset != NULL) 1134d8caf56eSAndrey V. Elsukov hlen = *offset; 1135d8caf56eSAndrey V. Elsukov else 1136d8caf56eSAndrey V. Elsukov hlen = 0; 1137d8caf56eSAndrey V. Elsukov 1138d8caf56eSAndrey V. Elsukov if (m->m_len < hlen + sizeof(*ip6)) 1139d8caf56eSAndrey V. Elsukov return (-1); 1140d8caf56eSAndrey V. Elsukov 1141d8caf56eSAndrey V. Elsukov ip6 = mtodo(m, hlen); 1142d8caf56eSAndrey V. Elsukov hlen += sizeof(*ip6); 1143d8caf56eSAndrey V. Elsukov proto = ip6->ip6_nxt; 1144d8caf56eSAndrey V. Elsukov /* Skip extension headers */ 1145d8caf56eSAndrey V. Elsukov while (proto == IPPROTO_HOPOPTS || proto == IPPROTO_ROUTING || 1146d8caf56eSAndrey V. Elsukov proto == IPPROTO_DSTOPTS) { 1147d8caf56eSAndrey V. Elsukov hbh = mtodo(m, hlen); 1148d8caf56eSAndrey V. Elsukov /* 1149d8caf56eSAndrey V. Elsukov * We expect mbuf has contigious data up to 1150d8caf56eSAndrey V. Elsukov * upper level header. 1151d8caf56eSAndrey V. Elsukov */ 1152d8caf56eSAndrey V. Elsukov if (m->m_len < hlen) 1153d8caf56eSAndrey V. Elsukov return (-1); 1154d8caf56eSAndrey V. Elsukov /* 1155d8caf56eSAndrey V. Elsukov * We doesn't support Jumbo payload option, 1156d8caf56eSAndrey V. Elsukov * so return error. 1157d8caf56eSAndrey V. Elsukov */ 1158d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_HOPOPTS && ip6->ip6_plen == 0) 1159d8caf56eSAndrey V. Elsukov return (-1); 1160d8caf56eSAndrey V. Elsukov proto = hbh->ip6h_nxt; 1161785c0d4dSAndrey V. Elsukov hlen += (hbh->ip6h_len + 1) << 3; 1162d8caf56eSAndrey V. Elsukov } 1163d8caf56eSAndrey V. Elsukov if (offset != NULL) 1164d8caf56eSAndrey V. Elsukov *offset = hlen; 1165d8caf56eSAndrey V. Elsukov return (proto); 1166d8caf56eSAndrey V. Elsukov } 1167d8caf56eSAndrey V. Elsukov 1168d8caf56eSAndrey V. Elsukov int 1169d8caf56eSAndrey V. Elsukov nat64_do_handle_ip4(struct mbuf *m, struct in6_addr *saddr, 1170782360deSAndrey V. Elsukov struct in6_addr *daddr, uint16_t lport, struct nat64_config *cfg, 1171d8caf56eSAndrey V. Elsukov void *logdata) 1172d8caf56eSAndrey V. Elsukov { 1173c570565fSAndrey V. Elsukov struct nhop6_basic nh; 1174d8caf56eSAndrey V. Elsukov struct ip6_hdr ip6; 1175c570565fSAndrey V. Elsukov struct sockaddr_in6 dst; 1176d8caf56eSAndrey V. Elsukov struct ip *ip; 1177d8caf56eSAndrey V. Elsukov struct mbufq mq; 1178d8caf56eSAndrey V. Elsukov uint16_t ip_id, ip_off; 1179d8caf56eSAndrey V. Elsukov uint16_t *csum; 1180d8caf56eSAndrey V. Elsukov int plen, hlen; 1181d8caf56eSAndrey V. Elsukov uint8_t proto; 1182d8caf56eSAndrey V. Elsukov 1183d8caf56eSAndrey V. Elsukov ip = mtod(m, struct ip*); 1184d8caf56eSAndrey V. Elsukov 1185d8caf56eSAndrey V. Elsukov if (ip->ip_ttl <= IPTTLDEC) { 1186d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_TIMXCEED, 1187782360deSAndrey V. Elsukov ICMP_TIMXCEED_INTRANS, 0, &cfg->stats, logdata); 1188d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1189d8caf56eSAndrey V. Elsukov } 1190d8caf56eSAndrey V. Elsukov 1191d8caf56eSAndrey V. Elsukov ip6.ip6_dst = *daddr; 1192d8caf56eSAndrey V. Elsukov ip6.ip6_src = *saddr; 1193d8caf56eSAndrey V. Elsukov 1194d8caf56eSAndrey V. Elsukov hlen = ip->ip_hl << 2; 1195d8caf56eSAndrey V. Elsukov plen = ntohs(ip->ip_len) - hlen; 1196d8caf56eSAndrey V. Elsukov proto = ip->ip_p; 1197d8caf56eSAndrey V. Elsukov 1198d8caf56eSAndrey V. Elsukov /* Save ip_id and ip_off, both are in network byte order */ 1199d8caf56eSAndrey V. Elsukov ip_id = ip->ip_id; 1200d8caf56eSAndrey V. Elsukov ip_off = ip->ip_off & htons(IP_OFFMASK | IP_MF); 1201d8caf56eSAndrey V. Elsukov 1202d8caf56eSAndrey V. Elsukov /* Fragment length must be multiple of 8 octets */ 1203d8caf56eSAndrey V. Elsukov if ((ip->ip_off & htons(IP_MF)) != 0 && (plen & 0x7) != 0) { 1204d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_PARAMPROB, 1205782360deSAndrey V. Elsukov ICMP_PARAMPROB_LENGTH, 0, &cfg->stats, logdata); 1206d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1207d8caf56eSAndrey V. Elsukov } 1208d8caf56eSAndrey V. Elsukov /* Fragmented ICMP is unsupported */ 1209d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_ICMP && ip_off != 0) { 1210d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to fragmented ICMP"); 1211782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1212d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1213d8caf56eSAndrey V. Elsukov } 1214d8caf56eSAndrey V. Elsukov 1215c570565fSAndrey V. Elsukov dst.sin6_addr = ip6.ip6_dst; 1216c570565fSAndrey V. Elsukov if (nat64_find_route6(&nh, &dst, m) != 0) { 1217782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, noroute6); 1218d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 1219782360deSAndrey V. Elsukov &cfg->stats, logdata); 1220d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1221d8caf56eSAndrey V. Elsukov } 1222c570565fSAndrey V. Elsukov if (nh.nh_mtu < plen + sizeof(ip6) && 1223c570565fSAndrey V. Elsukov (ip->ip_off & htons(IP_DF)) != 0) { 1224d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 1225782360deSAndrey V. Elsukov FRAGSZ(nh.nh_mtu) + sizeof(struct ip), &cfg->stats, logdata); 1226d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1227d8caf56eSAndrey V. Elsukov } 1228d8caf56eSAndrey V. Elsukov 1229d8caf56eSAndrey V. Elsukov ip6.ip6_flow = htonl(ip->ip_tos << 20); 1230d8caf56eSAndrey V. Elsukov ip6.ip6_vfc |= IPV6_VERSION; 1231d8caf56eSAndrey V. Elsukov ip6.ip6_hlim = ip->ip_ttl; 1232aa271561SAndrey V. Elsukov /* Forwarding code will decrement TTL for netisr based output. */ 1233aa271561SAndrey V. Elsukov if (V_nat64out == &nat64_direct) 1234aa271561SAndrey V. Elsukov ip6.ip6_hlim -= IPTTLDEC; 1235d8caf56eSAndrey V. Elsukov ip6.ip6_plen = htons(plen); 1236d8caf56eSAndrey V. Elsukov ip6.ip6_nxt = (proto == IPPROTO_ICMP) ? IPPROTO_ICMPV6: proto; 1237d8caf56eSAndrey V. Elsukov /* Convert checksums. */ 1238d8caf56eSAndrey V. Elsukov switch (proto) { 1239d8caf56eSAndrey V. Elsukov case IPPROTO_TCP: 1240d8caf56eSAndrey V. Elsukov csum = &TCP(mtodo(m, hlen))->th_sum; 1241d8caf56eSAndrey V. Elsukov if (lport != 0) { 1242d8caf56eSAndrey V. Elsukov struct tcphdr *tcp = TCP(mtodo(m, hlen)); 1243d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, tcp->th_dport, lport); 1244d8caf56eSAndrey V. Elsukov tcp->th_dport = lport; 1245d8caf56eSAndrey V. Elsukov } 1246d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, ~nat64_cksum_convert(&ip6, ip)); 1247d8caf56eSAndrey V. Elsukov break; 1248d8caf56eSAndrey V. Elsukov case IPPROTO_UDP: 1249d8caf56eSAndrey V. Elsukov csum = &UDP(mtodo(m, hlen))->uh_sum; 1250d8caf56eSAndrey V. Elsukov if (lport != 0) { 1251d8caf56eSAndrey V. Elsukov struct udphdr *udp = UDP(mtodo(m, hlen)); 1252d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, udp->uh_dport, lport); 1253d8caf56eSAndrey V. Elsukov udp->uh_dport = lport; 1254d8caf56eSAndrey V. Elsukov } 1255d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, ~nat64_cksum_convert(&ip6, ip)); 1256d8caf56eSAndrey V. Elsukov break; 1257d8caf56eSAndrey V. Elsukov case IPPROTO_ICMP: 1258782360deSAndrey V. Elsukov m = nat64_icmp_translate(m, &ip6, lport, hlen, cfg); 1259c570565fSAndrey V. Elsukov if (m == NULL) /* stats already accounted */ 1260d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1261d8caf56eSAndrey V. Elsukov } 1262d8caf56eSAndrey V. Elsukov 1263d8caf56eSAndrey V. Elsukov m_adj(m, hlen); 1264d8caf56eSAndrey V. Elsukov mbufq_init(&mq, 255); 1265782360deSAndrey V. Elsukov nat64_fragment6(&cfg->stats, &ip6, &mq, m, nh.nh_mtu, ip_id, ip_off); 1266d8caf56eSAndrey V. Elsukov while ((m = mbufq_dequeue(&mq)) != NULL) { 1267aa271561SAndrey V. Elsukov if (V_nat64out->output(nh.nh_ifp, m, (struct sockaddr *)&dst, 1268782360deSAndrey V. Elsukov &cfg->stats, logdata) != 0) 1269d8caf56eSAndrey V. Elsukov break; 1270782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, opcnt46); 1271d8caf56eSAndrey V. Elsukov } 1272d8caf56eSAndrey V. Elsukov mbufq_drain(&mq); 1273d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1274d8caf56eSAndrey V. Elsukov } 1275d8caf56eSAndrey V. Elsukov 1276d8caf56eSAndrey V. Elsukov int 1277d8caf56eSAndrey V. Elsukov nat64_handle_icmp6(struct mbuf *m, int hlen, uint32_t aaddr, uint16_t aport, 1278782360deSAndrey V. Elsukov struct nat64_config *cfg, void *logdata) 1279d8caf56eSAndrey V. Elsukov { 1280d8caf56eSAndrey V. Elsukov struct ip ip; 1281d8caf56eSAndrey V. Elsukov struct icmp6_hdr *icmp6; 1282d8caf56eSAndrey V. Elsukov struct ip6_frag *ip6f; 1283d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6, *ip6i; 1284d8caf56eSAndrey V. Elsukov uint32_t mtu; 1285d8caf56eSAndrey V. Elsukov int plen, proto; 1286d8caf56eSAndrey V. Elsukov uint8_t type, code; 1287d8caf56eSAndrey V. Elsukov 1288d8caf56eSAndrey V. Elsukov if (hlen == 0) { 1289d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 1290d8caf56eSAndrey V. Elsukov if (nat64_check_ip6(&ip6->ip6_src) != 0 || 1291d8caf56eSAndrey V. Elsukov nat64_check_ip6(&ip6->ip6_dst) != 0) 1292d8caf56eSAndrey V. Elsukov return (NAT64SKIP); 1293d8caf56eSAndrey V. Elsukov 1294d8caf56eSAndrey V. Elsukov proto = nat64_getlasthdr(m, &hlen); 1295d8caf56eSAndrey V. Elsukov if (proto != IPPROTO_ICMPV6) { 1296d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, 1297d8caf56eSAndrey V. Elsukov "dropped due to mbuf isn't contigious"); 1298782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1299d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1300d8caf56eSAndrey V. Elsukov } 1301d8caf56eSAndrey V. Elsukov } 1302d8caf56eSAndrey V. Elsukov 1303d8caf56eSAndrey V. Elsukov /* 1304d8caf56eSAndrey V. Elsukov * Translate ICMPv6 type and code to ICMPv4 (RFC7915). 1305d8caf56eSAndrey V. Elsukov * NOTE: ICMPv6 echo handled by nat64_do_handle_ip6(). 1306d8caf56eSAndrey V. Elsukov */ 1307d8caf56eSAndrey V. Elsukov icmp6 = mtodo(m, hlen); 1308d8caf56eSAndrey V. Elsukov mtu = 0; 1309d8caf56eSAndrey V. Elsukov switch (icmp6->icmp6_type) { 1310d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH: 1311d8caf56eSAndrey V. Elsukov type = ICMP_UNREACH; 1312d8caf56eSAndrey V. Elsukov switch (icmp6->icmp6_code) { 1313d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_NOROUTE: 1314d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_BEYONDSCOPE: 1315d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_ADDR: 1316d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_HOST; 1317d8caf56eSAndrey V. Elsukov break; 1318d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_ADMIN: 1319d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_HOST_PROHIB; 1320d8caf56eSAndrey V. Elsukov break; 1321d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_NOPORT: 1322d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_PORT; 1323d8caf56eSAndrey V. Elsukov break; 1324d8caf56eSAndrey V. Elsukov default: 1325d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d," 1326d8caf56eSAndrey V. Elsukov " code %d", icmp6->icmp6_type, 1327d8caf56eSAndrey V. Elsukov icmp6->icmp6_code); 1328782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1329d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1330d8caf56eSAndrey V. Elsukov } 1331d8caf56eSAndrey V. Elsukov break; 1332d8caf56eSAndrey V. Elsukov case ICMP6_PACKET_TOO_BIG: 1333d8caf56eSAndrey V. Elsukov type = ICMP_UNREACH; 1334d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_NEEDFRAG; 1335d8caf56eSAndrey V. Elsukov mtu = ntohl(icmp6->icmp6_mtu); 1336d8caf56eSAndrey V. Elsukov if (mtu < IPV6_MMTU) { 1337d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Wrong MTU %d in ICMPv6 type %d," 1338d8caf56eSAndrey V. Elsukov " code %d", mtu, icmp6->icmp6_type, 1339d8caf56eSAndrey V. Elsukov icmp6->icmp6_code); 1340782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1341d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1342d8caf56eSAndrey V. Elsukov } 1343d8caf56eSAndrey V. Elsukov /* 1344d8caf56eSAndrey V. Elsukov * Adjust MTU to reflect difference between 1345d8caf56eSAndrey V. Elsukov * IPv6 an IPv4 headers. 1346d8caf56eSAndrey V. Elsukov */ 1347d8caf56eSAndrey V. Elsukov mtu -= sizeof(struct ip6_hdr) - sizeof(struct ip); 1348d8caf56eSAndrey V. Elsukov break; 1349c5f2dbb6SAndrey V. Elsukov case ICMP6_TIME_EXCEEDED: 1350d8caf56eSAndrey V. Elsukov type = ICMP_TIMXCEED; 1351c5f2dbb6SAndrey V. Elsukov code = icmp6->icmp6_code; 1352d8caf56eSAndrey V. Elsukov break; 1353d8caf56eSAndrey V. Elsukov case ICMP6_PARAM_PROB: 1354d8caf56eSAndrey V. Elsukov switch (icmp6->icmp6_code) { 1355d8caf56eSAndrey V. Elsukov case ICMP6_PARAMPROB_HEADER: 1356d8caf56eSAndrey V. Elsukov type = ICMP_PARAMPROB; 1357d8caf56eSAndrey V. Elsukov code = ICMP_PARAMPROB_ERRATPTR; 1358d8caf56eSAndrey V. Elsukov mtu = ntohl(icmp6->icmp6_pptr); 1359d8caf56eSAndrey V. Elsukov switch (mtu) { 1360d8caf56eSAndrey V. Elsukov case 0: /* Version/Traffic Class */ 1361d8caf56eSAndrey V. Elsukov case 1: /* Traffic Class/Flow Label */ 1362d8caf56eSAndrey V. Elsukov break; 1363d8caf56eSAndrey V. Elsukov case 4: /* Payload Length */ 1364d8caf56eSAndrey V. Elsukov case 5: 1365d8caf56eSAndrey V. Elsukov mtu = 2; 1366d8caf56eSAndrey V. Elsukov break; 1367d8caf56eSAndrey V. Elsukov case 6: /* Next Header */ 1368d8caf56eSAndrey V. Elsukov mtu = 9; 1369d8caf56eSAndrey V. Elsukov break; 1370d8caf56eSAndrey V. Elsukov case 7: /* Hop Limit */ 1371d8caf56eSAndrey V. Elsukov mtu = 8; 1372d8caf56eSAndrey V. Elsukov break; 1373d8caf56eSAndrey V. Elsukov default: 1374d8caf56eSAndrey V. Elsukov if (mtu >= 8 && mtu <= 23) { 1375d8caf56eSAndrey V. Elsukov mtu = 12; /* Source address */ 1376d8caf56eSAndrey V. Elsukov break; 1377d8caf56eSAndrey V. Elsukov } 1378d8caf56eSAndrey V. Elsukov if (mtu >= 24 && mtu <= 39) { 1379d8caf56eSAndrey V. Elsukov mtu = 16; /* Destination address */ 1380d8caf56eSAndrey V. Elsukov break; 1381d8caf56eSAndrey V. Elsukov } 1382d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d," 1383d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp6->icmp6_type, 1384d8caf56eSAndrey V. Elsukov icmp6->icmp6_code, mtu); 1385782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1386d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1387d8caf56eSAndrey V. Elsukov } 1388d8caf56eSAndrey V. Elsukov case ICMP6_PARAMPROB_NEXTHEADER: 1389d8caf56eSAndrey V. Elsukov type = ICMP_UNREACH; 1390d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_PROTOCOL; 1391d8caf56eSAndrey V. Elsukov break; 1392d8caf56eSAndrey V. Elsukov default: 1393d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d," 1394d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp6->icmp6_type, 1395d8caf56eSAndrey V. Elsukov icmp6->icmp6_code, ntohl(icmp6->icmp6_pptr)); 1396782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1397d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1398d8caf56eSAndrey V. Elsukov } 1399d8caf56eSAndrey V. Elsukov break; 1400d8caf56eSAndrey V. Elsukov default: 1401d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d, code %d", 1402d8caf56eSAndrey V. Elsukov icmp6->icmp6_type, icmp6->icmp6_code); 1403782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1404d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1405d8caf56eSAndrey V. Elsukov } 1406d8caf56eSAndrey V. Elsukov 1407d8caf56eSAndrey V. Elsukov hlen += sizeof(struct icmp6_hdr); 1408d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + sizeof(struct ip6_hdr) + ICMP_MINLEN) { 1409782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1410d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Message is too short %d", 1411d8caf56eSAndrey V. Elsukov m->m_pkthdr.len); 1412d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1413d8caf56eSAndrey V. Elsukov } 1414d8caf56eSAndrey V. Elsukov /* 1415d8caf56eSAndrey V. Elsukov * We need at least ICMP_MINLEN bytes of original datagram payload 1416d8caf56eSAndrey V. Elsukov * to generate ICMP message. It is nice that ICMP_MINLEN is equal 1417d8caf56eSAndrey V. Elsukov * to sizeof(struct ip6_frag). So, if embedded datagram had a fragment 1418d8caf56eSAndrey V. Elsukov * header we will not have to do m_pullup() again. 1419d8caf56eSAndrey V. Elsukov * 1420d8caf56eSAndrey V. Elsukov * What we have here: 1421d8caf56eSAndrey V. Elsukov * Outer header: (IPv6iGW, v4mapPRefix+v4exthost) 1422d8caf56eSAndrey V. Elsukov * Inner header: (v4mapPRefix+v4host, IPv6iHost) [sport, dport] 1423d8caf56eSAndrey V. Elsukov * We need to translate it to: 1424d8caf56eSAndrey V. Elsukov * 1425d8caf56eSAndrey V. Elsukov * Outer header: (alias_host, v4exthost) 1426d8caf56eSAndrey V. Elsukov * Inner header: (v4exthost, alias_host) [sport, alias_port] 1427d8caf56eSAndrey V. Elsukov * 1428d8caf56eSAndrey V. Elsukov * Assume caller function has checked if v4mapPRefix+v4host 1429d8caf56eSAndrey V. Elsukov * matches configured prefix. 1430d8caf56eSAndrey V. Elsukov * The only two things we should be provided with are mapping between 1431d8caf56eSAndrey V. Elsukov * IPv6iHost <> alias_host and between dport and alias_port. 1432d8caf56eSAndrey V. Elsukov */ 1433d8caf56eSAndrey V. Elsukov if (m->m_len < hlen + sizeof(struct ip6_hdr) + ICMP_MINLEN) 1434d8caf56eSAndrey V. Elsukov m = m_pullup(m, hlen + sizeof(struct ip6_hdr) + ICMP_MINLEN); 1435d8caf56eSAndrey V. Elsukov if (m == NULL) { 1436782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, nomem); 1437d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1438d8caf56eSAndrey V. Elsukov } 1439d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 1440d8caf56eSAndrey V. Elsukov ip6i = mtodo(m, hlen); 1441d8caf56eSAndrey V. Elsukov ip6f = NULL; 1442d8caf56eSAndrey V. Elsukov proto = ip6i->ip6_nxt; 1443d8caf56eSAndrey V. Elsukov plen = ntohs(ip6i->ip6_plen); 1444d8caf56eSAndrey V. Elsukov hlen += sizeof(struct ip6_hdr); 1445d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_FRAGMENT) { 1446d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + sizeof(struct ip6_frag) + 1447d8caf56eSAndrey V. Elsukov ICMP_MINLEN) 1448d8caf56eSAndrey V. Elsukov goto fail; 1449d8caf56eSAndrey V. Elsukov ip6f = mtodo(m, hlen); 1450d8caf56eSAndrey V. Elsukov proto = ip6f->ip6f_nxt; 1451d8caf56eSAndrey V. Elsukov plen -= sizeof(struct ip6_frag); 1452d8caf56eSAndrey V. Elsukov hlen += sizeof(struct ip6_frag); 1453d8caf56eSAndrey V. Elsukov /* Ajust MTU to reflect frag header size */ 1454d8caf56eSAndrey V. Elsukov if (type == ICMP_UNREACH && code == ICMP_UNREACH_NEEDFRAG) 1455d8caf56eSAndrey V. Elsukov mtu -= sizeof(struct ip6_frag); 1456d8caf56eSAndrey V. Elsukov } 1457d8caf56eSAndrey V. Elsukov if (proto != IPPROTO_TCP && proto != IPPROTO_UDP) { 1458d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported proto %d in the inner header", 1459d8caf56eSAndrey V. Elsukov proto); 1460d8caf56eSAndrey V. Elsukov goto fail; 1461d8caf56eSAndrey V. Elsukov } 1462d8caf56eSAndrey V. Elsukov if (nat64_check_ip6(&ip6i->ip6_src) != 0 || 1463d8caf56eSAndrey V. Elsukov nat64_check_ip6(&ip6i->ip6_dst) != 0) { 1464d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Inner addresses do not passes the check"); 1465d8caf56eSAndrey V. Elsukov goto fail; 1466d8caf56eSAndrey V. Elsukov } 1467d8caf56eSAndrey V. Elsukov /* Check if outer dst is the same as inner src */ 1468d8caf56eSAndrey V. Elsukov if (!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &ip6i->ip6_src)) { 1469d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Inner src doesn't match outer dst"); 1470d8caf56eSAndrey V. Elsukov goto fail; 1471d8caf56eSAndrey V. Elsukov } 1472d8caf56eSAndrey V. Elsukov 1473d8caf56eSAndrey V. Elsukov /* Now we need to make a fake IPv4 packet to generate ICMP message */ 1474d8caf56eSAndrey V. Elsukov ip.ip_dst.s_addr = aaddr; 1475b11efc1eSAndrey V. Elsukov ip.ip_src.s_addr = nat64_extract_ip4(&ip6i->ip6_src, cfg->plat_plen); 1476b11efc1eSAndrey V. Elsukov if (ip.ip_src.s_addr == 0) 1477b11efc1eSAndrey V. Elsukov goto fail; 1478d8caf56eSAndrey V. Elsukov /* XXX: Make fake ulp header */ 1479aa271561SAndrey V. Elsukov if (V_nat64out == &nat64_direct) /* init_ip4hdr will decrement it */ 1480aa271561SAndrey V. Elsukov ip6i->ip6_hlim += IPV6_HLIMDEC; 1481d8caf56eSAndrey V. Elsukov nat64_init_ip4hdr(ip6i, ip6f, plen, proto, &ip); 1482d8caf56eSAndrey V. Elsukov m_adj(m, hlen - sizeof(struct ip)); 1483d8caf56eSAndrey V. Elsukov bcopy(&ip, mtod(m, void *), sizeof(ip)); 1484782360deSAndrey V. Elsukov nat64_icmp_reflect(m, type, code, (uint16_t)mtu, &cfg->stats, 1485782360deSAndrey V. Elsukov logdata); 1486d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1487d8caf56eSAndrey V. Elsukov fail: 1488d8caf56eSAndrey V. Elsukov /* 1489d8caf56eSAndrey V. Elsukov * We must call m_freem() because mbuf pointer could be 1490d8caf56eSAndrey V. Elsukov * changed with m_pullup(). 1491d8caf56eSAndrey V. Elsukov */ 1492d8caf56eSAndrey V. Elsukov m_freem(m); 1493782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1494d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1495d8caf56eSAndrey V. Elsukov } 1496d8caf56eSAndrey V. Elsukov 1497d8caf56eSAndrey V. Elsukov int 1498d8caf56eSAndrey V. Elsukov nat64_do_handle_ip6(struct mbuf *m, uint32_t aaddr, uint16_t aport, 1499782360deSAndrey V. Elsukov struct nat64_config *cfg, void *logdata) 1500d8caf56eSAndrey V. Elsukov { 1501d8caf56eSAndrey V. Elsukov struct ip ip; 1502c570565fSAndrey V. Elsukov struct nhop4_basic nh; 1503c570565fSAndrey V. Elsukov struct sockaddr_in dst; 1504d8caf56eSAndrey V. Elsukov struct ip6_frag *frag; 1505d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6; 1506d8caf56eSAndrey V. Elsukov struct icmp6_hdr *icmp6; 1507d8caf56eSAndrey V. Elsukov uint16_t *csum; 1508db68f783SBjoern A. Zeeb int plen, hlen, proto; 1509d8caf56eSAndrey V. Elsukov 1510d8caf56eSAndrey V. Elsukov /* 1511d8caf56eSAndrey V. Elsukov * XXX: we expect ipfw_chk() did m_pullup() up to upper level 1512d8caf56eSAndrey V. Elsukov * protocol's headers. Also we skip some checks, that ip6_input(), 1513d8caf56eSAndrey V. Elsukov * ip6_forward(), ip6_fastfwd() and ipfw_chk() already did. 1514d8caf56eSAndrey V. Elsukov */ 1515d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 1516d8caf56eSAndrey V. Elsukov if (nat64_check_ip6(&ip6->ip6_src) != 0 || 1517d8caf56eSAndrey V. Elsukov nat64_check_ip6(&ip6->ip6_dst) != 0) { 1518d8caf56eSAndrey V. Elsukov return (NAT64SKIP); 1519d8caf56eSAndrey V. Elsukov } 1520d8caf56eSAndrey V. Elsukov 1521d8caf56eSAndrey V. Elsukov /* Starting from this point we must not return zero */ 1522d8caf56eSAndrey V. Elsukov ip.ip_src.s_addr = aaddr; 1523d8caf56eSAndrey V. Elsukov if (nat64_check_ip4(ip.ip_src.s_addr) != 0) { 1524782360deSAndrey V. Elsukov DPRINTF(DP_GENERIC | DP_DROPS, "invalid source address: %08x", 1525d8caf56eSAndrey V. Elsukov ip.ip_src.s_addr); 1526782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1527d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1528d8caf56eSAndrey V. Elsukov } 1529d8caf56eSAndrey V. Elsukov 1530b11efc1eSAndrey V. Elsukov ip.ip_dst.s_addr = nat64_extract_ip4(&ip6->ip6_dst, cfg->plat_plen); 1531d8caf56eSAndrey V. Elsukov if (ip.ip_dst.s_addr == 0) { 1532782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1533d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1534d8caf56eSAndrey V. Elsukov } 1535d8caf56eSAndrey V. Elsukov 1536d8caf56eSAndrey V. Elsukov if (ip6->ip6_hlim <= IPV6_HLIMDEC) { 1537d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_TIME_EXCEEDED, 1538782360deSAndrey V. Elsukov ICMP6_TIME_EXCEED_TRANSIT, 0, &cfg->stats, logdata); 1539d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1540d8caf56eSAndrey V. Elsukov } 1541d8caf56eSAndrey V. Elsukov 1542d8caf56eSAndrey V. Elsukov hlen = 0; 1543d8caf56eSAndrey V. Elsukov plen = ntohs(ip6->ip6_plen); 1544d8caf56eSAndrey V. Elsukov proto = nat64_getlasthdr(m, &hlen); 1545d8caf56eSAndrey V. Elsukov if (proto < 0) { 1546d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to mbuf isn't contigious"); 1547782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1548d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1549d8caf56eSAndrey V. Elsukov } 1550d8caf56eSAndrey V. Elsukov frag = NULL; 1551d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_FRAGMENT) { 1552d8caf56eSAndrey V. Elsukov /* ipfw_chk should m_pullup up to frag header */ 1553d8caf56eSAndrey V. Elsukov if (m->m_len < hlen + sizeof(*frag)) { 1554d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, 1555d8caf56eSAndrey V. Elsukov "dropped due to mbuf isn't contigious"); 1556782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1557d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1558d8caf56eSAndrey V. Elsukov } 1559d8caf56eSAndrey V. Elsukov frag = mtodo(m, hlen); 1560d8caf56eSAndrey V. Elsukov proto = frag->ip6f_nxt; 1561d8caf56eSAndrey V. Elsukov hlen += sizeof(*frag); 1562d8caf56eSAndrey V. Elsukov /* Fragmented ICMPv6 is unsupported */ 1563d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_ICMPV6) { 1564d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to fragmented ICMPv6"); 1565782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1566d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1567d8caf56eSAndrey V. Elsukov } 1568d8caf56eSAndrey V. Elsukov /* Fragment length must be multiple of 8 octets */ 1569d8caf56eSAndrey V. Elsukov if ((frag->ip6f_offlg & IP6F_MORE_FRAG) != 0 && 1570d8caf56eSAndrey V. Elsukov ((plen + sizeof(struct ip6_hdr) - hlen) & 0x7) != 0) { 1571d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_PARAM_PROB, 1572d8caf56eSAndrey V. Elsukov ICMP6_PARAMPROB_HEADER, 1573782360deSAndrey V. Elsukov offsetof(struct ip6_hdr, ip6_plen), &cfg->stats, 1574d8caf56eSAndrey V. Elsukov logdata); 1575d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1576d8caf56eSAndrey V. Elsukov } 1577d8caf56eSAndrey V. Elsukov } 1578d8caf56eSAndrey V. Elsukov plen -= hlen - sizeof(struct ip6_hdr); 1579d8caf56eSAndrey V. Elsukov if (plen < 0 || m->m_pkthdr.len < plen + hlen) { 1580d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "plen %d, pkthdr.len %d, hlen %d", 1581d8caf56eSAndrey V. Elsukov plen, m->m_pkthdr.len, hlen); 1582782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1583d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1584d8caf56eSAndrey V. Elsukov } 1585d8caf56eSAndrey V. Elsukov 1586d8caf56eSAndrey V. Elsukov icmp6 = NULL; /* Make gcc happy */ 1587d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_ICMPV6) { 1588d8caf56eSAndrey V. Elsukov icmp6 = mtodo(m, hlen); 1589d8caf56eSAndrey V. Elsukov if (icmp6->icmp6_type != ICMP6_ECHO_REQUEST && 1590d8caf56eSAndrey V. Elsukov icmp6->icmp6_type != ICMP6_ECHO_REPLY) 1591d8caf56eSAndrey V. Elsukov return (nat64_handle_icmp6(m, hlen, aaddr, aport, 1592782360deSAndrey V. Elsukov cfg, logdata)); 1593d8caf56eSAndrey V. Elsukov } 1594c570565fSAndrey V. Elsukov dst.sin_addr.s_addr = ip.ip_dst.s_addr; 1595c570565fSAndrey V. Elsukov if (nat64_find_route4(&nh, &dst, m) != 0) { 1596782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, noroute4); 1597d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_DST_UNREACH, 1598782360deSAndrey V. Elsukov ICMP6_DST_UNREACH_NOROUTE, 0, &cfg->stats, logdata); 1599d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1600d8caf56eSAndrey V. Elsukov } 1601c570565fSAndrey V. Elsukov if (nh.nh_mtu < plen + sizeof(ip)) { 1602c570565fSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_PACKET_TOO_BIG, 0, nh.nh_mtu, 1603782360deSAndrey V. Elsukov &cfg->stats, logdata); 1604d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1605d8caf56eSAndrey V. Elsukov } 1606d8caf56eSAndrey V. Elsukov nat64_init_ip4hdr(ip6, frag, plen, proto, &ip); 1607d8caf56eSAndrey V. Elsukov /* Convert checksums. */ 1608d8caf56eSAndrey V. Elsukov switch (proto) { 1609d8caf56eSAndrey V. Elsukov case IPPROTO_TCP: 1610d8caf56eSAndrey V. Elsukov csum = &TCP(mtodo(m, hlen))->th_sum; 1611d8caf56eSAndrey V. Elsukov if (aport != 0) { 1612d8caf56eSAndrey V. Elsukov struct tcphdr *tcp = TCP(mtodo(m, hlen)); 1613d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, tcp->th_sport, aport); 1614d8caf56eSAndrey V. Elsukov tcp->th_sport = aport; 1615d8caf56eSAndrey V. Elsukov } 1616d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, nat64_cksum_convert(ip6, &ip)); 1617d8caf56eSAndrey V. Elsukov break; 1618d8caf56eSAndrey V. Elsukov case IPPROTO_UDP: 1619d8caf56eSAndrey V. Elsukov csum = &UDP(mtodo(m, hlen))->uh_sum; 1620d8caf56eSAndrey V. Elsukov if (aport != 0) { 1621d8caf56eSAndrey V. Elsukov struct udphdr *udp = UDP(mtodo(m, hlen)); 1622d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, udp->uh_sport, aport); 1623d8caf56eSAndrey V. Elsukov udp->uh_sport = aport; 1624d8caf56eSAndrey V. Elsukov } 1625d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, nat64_cksum_convert(ip6, &ip)); 1626d8caf56eSAndrey V. Elsukov break; 1627d8caf56eSAndrey V. Elsukov case IPPROTO_ICMPV6: 1628d8caf56eSAndrey V. Elsukov /* Checksum in ICMPv6 covers pseudo header */ 1629d8caf56eSAndrey V. Elsukov csum = &icmp6->icmp6_cksum; 1630d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, in6_cksum_pseudo(ip6, plen, 1631d8caf56eSAndrey V. Elsukov IPPROTO_ICMPV6, 0)); 1632d8caf56eSAndrey V. Elsukov /* Convert ICMPv6 types to ICMP */ 1633c570565fSAndrey V. Elsukov proto = *(uint16_t *)icmp6; /* save old word for cksum_adjust */ 1634d8caf56eSAndrey V. Elsukov if (icmp6->icmp6_type == ICMP6_ECHO_REQUEST) 1635d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = ICMP_ECHO; 1636d8caf56eSAndrey V. Elsukov else /* ICMP6_ECHO_REPLY */ 1637d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = ICMP_ECHOREPLY; 1638c570565fSAndrey V. Elsukov *csum = cksum_adjust(*csum, (uint16_t)proto, 1639c570565fSAndrey V. Elsukov *(uint16_t *)icmp6); 1640d8caf56eSAndrey V. Elsukov if (aport != 0) { 1641d8caf56eSAndrey V. Elsukov uint16_t old_id = icmp6->icmp6_id; 1642d8caf56eSAndrey V. Elsukov icmp6->icmp6_id = aport; 1643d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, old_id, aport); 1644d8caf56eSAndrey V. Elsukov } 1645d8caf56eSAndrey V. Elsukov break; 1646d8caf56eSAndrey V. Elsukov }; 1647d8caf56eSAndrey V. Elsukov 1648d8caf56eSAndrey V. Elsukov m_adj(m, hlen - sizeof(ip)); 1649d8caf56eSAndrey V. Elsukov bcopy(&ip, mtod(m, void *), sizeof(ip)); 1650aa271561SAndrey V. Elsukov if (V_nat64out->output(nh.nh_ifp, m, (struct sockaddr *)&dst, 1651782360deSAndrey V. Elsukov &cfg->stats, logdata) == 0) 1652782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, opcnt64); 1653d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1654d8caf56eSAndrey V. Elsukov } 1655d8caf56eSAndrey V. Elsukov 1656