1d8caf56eSAndrey V. Elsukov /*- 2782360deSAndrey V. Elsukov * Copyright (c) 2015-2018 Yandex LLC 3782360deSAndrey V. Elsukov * Copyright (c) 2015-2018 Andrey V. Elsukov <ae@FreeBSD.org> 4d8caf56eSAndrey V. Elsukov * All rights reserved. 5d8caf56eSAndrey V. Elsukov * 6d8caf56eSAndrey V. Elsukov * Redistribution and use in source and binary forms, with or without 7d8caf56eSAndrey V. Elsukov * modification, are permitted provided that the following conditions 8d8caf56eSAndrey V. Elsukov * are met: 9d8caf56eSAndrey V. Elsukov * 10d8caf56eSAndrey V. Elsukov * 1. Redistributions of source code must retain the above copyright 11d8caf56eSAndrey V. Elsukov * notice, this list of conditions and the following disclaimer. 12d8caf56eSAndrey V. Elsukov * 2. Redistributions in binary form must reproduce the above copyright 13d8caf56eSAndrey V. Elsukov * notice, this list of conditions and the following disclaimer in the 14d8caf56eSAndrey V. Elsukov * documentation and/or other materials provided with the distribution. 15d8caf56eSAndrey V. Elsukov * 16d8caf56eSAndrey V. Elsukov * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17d8caf56eSAndrey V. Elsukov * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18d8caf56eSAndrey V. Elsukov * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19d8caf56eSAndrey V. Elsukov * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20d8caf56eSAndrey V. Elsukov * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21d8caf56eSAndrey V. Elsukov * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22d8caf56eSAndrey V. Elsukov * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23d8caf56eSAndrey V. Elsukov * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24d8caf56eSAndrey V. Elsukov * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25d8caf56eSAndrey V. Elsukov * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26d8caf56eSAndrey V. Elsukov */ 27d8caf56eSAndrey V. Elsukov 28d8caf56eSAndrey V. Elsukov #include "opt_ipfw.h" 29d8caf56eSAndrey V. Elsukov 30d8caf56eSAndrey V. Elsukov #include <sys/cdefs.h> 31d8caf56eSAndrey V. Elsukov __FBSDID("$FreeBSD$"); 32d8caf56eSAndrey V. Elsukov 33d8caf56eSAndrey V. Elsukov #include <sys/param.h> 34d8caf56eSAndrey V. Elsukov #include <sys/systm.h> 35d8caf56eSAndrey V. Elsukov #include <sys/counter.h> 36d8caf56eSAndrey V. Elsukov #include <sys/errno.h> 37d8caf56eSAndrey V. Elsukov #include <sys/kernel.h> 38d8caf56eSAndrey V. Elsukov #include <sys/lock.h> 39d8caf56eSAndrey V. Elsukov #include <sys/mbuf.h> 40d8caf56eSAndrey V. Elsukov #include <sys/module.h> 41d8caf56eSAndrey V. Elsukov #include <sys/rmlock.h> 42d8caf56eSAndrey V. Elsukov #include <sys/rwlock.h> 43d8caf56eSAndrey V. Elsukov #include <sys/socket.h> 44d8caf56eSAndrey V. Elsukov #include <sys/queue.h> 45d8caf56eSAndrey V. Elsukov 46d8caf56eSAndrey V. Elsukov #include <net/if.h> 47d8caf56eSAndrey V. Elsukov #include <net/if_var.h> 48d8caf56eSAndrey V. Elsukov #include <net/if_pflog.h> 49d8caf56eSAndrey V. Elsukov #include <net/pfil.h> 50d8caf56eSAndrey V. Elsukov #include <net/netisr.h> 51d8caf56eSAndrey V. Elsukov #include <net/route.h> 52d8caf56eSAndrey V. Elsukov 53d8caf56eSAndrey V. Elsukov #include <netinet/in.h> 54c570565fSAndrey V. Elsukov #include <netinet/in_fib.h> 55d8caf56eSAndrey V. Elsukov #include <netinet/ip.h> 56d8caf56eSAndrey V. Elsukov #include <netinet/ip_var.h> 57d8caf56eSAndrey V. Elsukov #include <netinet/ip_fw.h> 58d8caf56eSAndrey V. Elsukov #include <netinet/ip6.h> 59d8caf56eSAndrey V. Elsukov #include <netinet/icmp6.h> 60d8caf56eSAndrey V. Elsukov #include <netinet/ip_icmp.h> 61d8caf56eSAndrey V. Elsukov #include <netinet/tcp.h> 62d8caf56eSAndrey V. Elsukov #include <netinet/udp.h> 63d8caf56eSAndrey V. Elsukov #include <netinet6/in6_var.h> 64c570565fSAndrey V. Elsukov #include <netinet6/in6_fib.h> 65d8caf56eSAndrey V. Elsukov #include <netinet6/ip6_var.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 74d8caf56eSAndrey V. Elsukov static void 75d8caf56eSAndrey V. Elsukov nat64_log(struct pfloghdr *logdata, struct mbuf *m, sa_family_t family) 76d8caf56eSAndrey V. Elsukov { 77d8caf56eSAndrey V. Elsukov 78d8caf56eSAndrey V. Elsukov logdata->dir = PF_OUT; 79d8caf56eSAndrey V. Elsukov logdata->af = family; 80d8caf56eSAndrey V. Elsukov ipfw_bpf_mtap2(logdata, PFLOG_HDRLEN, m); 81d8caf56eSAndrey V. Elsukov } 82c570565fSAndrey V. Elsukov 83d8caf56eSAndrey V. Elsukov #ifdef IPFIREWALL_NAT64_DIRECT_OUTPUT 84c570565fSAndrey V. Elsukov static NAT64NOINLINE int nat64_find_route4(struct nhop4_basic *, 85c570565fSAndrey V. Elsukov struct sockaddr_in *, struct mbuf *); 86c570565fSAndrey V. Elsukov static NAT64NOINLINE int nat64_find_route6(struct nhop6_basic *, 87c570565fSAndrey V. Elsukov struct sockaddr_in6 *, struct mbuf *); 88d8caf56eSAndrey V. Elsukov 89c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 90782360deSAndrey V. Elsukov nat64_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 91782360deSAndrey V. Elsukov struct nat64_counters *stats, void *logdata) 92d8caf56eSAndrey V. Elsukov { 93d8caf56eSAndrey V. Elsukov int error; 94d8caf56eSAndrey V. Elsukov 95d8caf56eSAndrey V. Elsukov if (logdata != NULL) 96d8caf56eSAndrey V. Elsukov nat64_log(logdata, m, dst->sa_family); 97782360deSAndrey V. Elsukov error = (*ifp->if_output)(ifp, m, dst, NULL); 98d8caf56eSAndrey V. Elsukov if (error != 0) 99d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, oerrors); 100d8caf56eSAndrey V. Elsukov return (error); 101d8caf56eSAndrey V. Elsukov } 102d8caf56eSAndrey V. Elsukov 103c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 104782360deSAndrey V. Elsukov nat64_output_one(struct mbuf *m, struct nat64_counters *stats, void *logdata) 105d8caf56eSAndrey V. Elsukov { 106c570565fSAndrey V. Elsukov struct nhop6_basic nh6; 107c570565fSAndrey V. Elsukov struct nhop4_basic nh4; 108c570565fSAndrey V. Elsukov struct sockaddr_in6 dst6; 109c570565fSAndrey V. Elsukov struct sockaddr_in dst4; 110d8caf56eSAndrey V. Elsukov struct sockaddr *dst; 111d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6; 112d8caf56eSAndrey V. Elsukov struct ip *ip4; 113c570565fSAndrey V. Elsukov struct ifnet *ifp; 114d8caf56eSAndrey V. Elsukov int error; 115d8caf56eSAndrey V. Elsukov 116d8caf56eSAndrey V. Elsukov ip4 = mtod(m, struct ip *); 117d8caf56eSAndrey V. Elsukov switch (ip4->ip_v) { 118d8caf56eSAndrey V. Elsukov case IPVERSION: 119c570565fSAndrey V. Elsukov dst4.sin_addr = ip4->ip_dst; 120c570565fSAndrey V. Elsukov error = nat64_find_route4(&nh4, &dst4, m); 121c570565fSAndrey V. Elsukov if (error != 0) 122d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, noroute4); 123c570565fSAndrey V. Elsukov else { 124c570565fSAndrey V. Elsukov ifp = nh4.nh_ifp; 125c570565fSAndrey V. Elsukov dst = (struct sockaddr *)&dst4; 126c570565fSAndrey V. Elsukov } 127d8caf56eSAndrey V. Elsukov break; 128d8caf56eSAndrey V. Elsukov case (IPV6_VERSION >> 4): 129c570565fSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 130c570565fSAndrey V. Elsukov dst6.sin6_addr = ip6->ip6_dst; 131c570565fSAndrey V. Elsukov error = nat64_find_route6(&nh6, &dst6, m); 132c570565fSAndrey V. Elsukov if (error != 0) 133d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, noroute6); 134c570565fSAndrey V. Elsukov else { 135c570565fSAndrey V. Elsukov ifp = nh6.nh_ifp; 136c570565fSAndrey V. Elsukov dst = (struct sockaddr *)&dst6; 137c570565fSAndrey V. Elsukov } 138d8caf56eSAndrey V. Elsukov break; 139d8caf56eSAndrey V. Elsukov default: 140d8caf56eSAndrey V. Elsukov m_freem(m); 141d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 142d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to unknown IP version"); 143d8caf56eSAndrey V. Elsukov return (EAFNOSUPPORT); 144d8caf56eSAndrey V. Elsukov } 145c570565fSAndrey V. Elsukov if (error != 0) { 146d8caf56eSAndrey V. Elsukov m_freem(m); 147d8caf56eSAndrey V. Elsukov return (EHOSTUNREACH); 148d8caf56eSAndrey V. Elsukov } 149d8caf56eSAndrey V. Elsukov if (logdata != NULL) 150d8caf56eSAndrey V. Elsukov nat64_log(logdata, m, dst->sa_family); 151c570565fSAndrey V. Elsukov error = (*ifp->if_output)(ifp, m, dst, NULL); 152d8caf56eSAndrey V. Elsukov if (error != 0) 153d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, oerrors); 154d8caf56eSAndrey V. Elsukov return (error); 155d8caf56eSAndrey V. Elsukov } 156d8caf56eSAndrey V. Elsukov #else /* !IPFIREWALL_NAT64_DIRECT_OUTPUT */ 157c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 158782360deSAndrey V. Elsukov nat64_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 159782360deSAndrey V. Elsukov struct nat64_counters *stats, void *logdata) 160d8caf56eSAndrey V. Elsukov { 161d8caf56eSAndrey V. Elsukov struct ip *ip4; 162d8caf56eSAndrey V. Elsukov int ret, af; 163d8caf56eSAndrey V. Elsukov 164d8caf56eSAndrey V. Elsukov ip4 = mtod(m, struct ip *); 165d8caf56eSAndrey V. Elsukov switch (ip4->ip_v) { 166d8caf56eSAndrey V. Elsukov case IPVERSION: 167d8caf56eSAndrey V. Elsukov af = AF_INET; 168d8caf56eSAndrey V. Elsukov ret = NETISR_IP; 169d8caf56eSAndrey V. Elsukov break; 170d8caf56eSAndrey V. Elsukov case (IPV6_VERSION >> 4): 171d8caf56eSAndrey V. Elsukov af = AF_INET6; 172d8caf56eSAndrey V. Elsukov ret = NETISR_IPV6; 173d8caf56eSAndrey V. Elsukov break; 174d8caf56eSAndrey V. Elsukov default: 175d8caf56eSAndrey V. Elsukov m_freem(m); 176d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 177d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "unknown IP version"); 178d8caf56eSAndrey V. Elsukov return (EAFNOSUPPORT); 179d8caf56eSAndrey V. Elsukov } 180d8caf56eSAndrey V. Elsukov if (logdata != NULL) 181d8caf56eSAndrey V. Elsukov nat64_log(logdata, m, af); 182d8caf56eSAndrey V. Elsukov ret = netisr_queue(ret, m); 183d8caf56eSAndrey V. Elsukov if (ret != 0) 184d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, oerrors); 185d8caf56eSAndrey V. Elsukov return (ret); 186d8caf56eSAndrey V. Elsukov } 187d8caf56eSAndrey V. Elsukov 188c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 189782360deSAndrey V. Elsukov nat64_output_one(struct mbuf *m, struct nat64_counters *stats, void *logdata) 190d8caf56eSAndrey V. Elsukov { 191d8caf56eSAndrey V. Elsukov 192782360deSAndrey V. Elsukov return (nat64_output(NULL, m, NULL, stats, logdata)); 193d8caf56eSAndrey V. Elsukov } 194d8caf56eSAndrey V. Elsukov #endif /* !IPFIREWALL_NAT64_DIRECT_OUTPUT */ 195d8caf56eSAndrey V. Elsukov 196782360deSAndrey V. Elsukov /* 197782360deSAndrey V. Elsukov * Check the given IPv6 prefix and length according to RFC6052: 198782360deSAndrey V. Elsukov * The prefixes can only have one of the following lengths: 199782360deSAndrey V. Elsukov * 32, 40, 48, 56, 64, or 96 (The Well-Known Prefix is 96 bits long). 200782360deSAndrey V. Elsukov * Returns zero on success, otherwise EINVAL. 201782360deSAndrey V. Elsukov */ 202782360deSAndrey V. Elsukov int 203782360deSAndrey V. Elsukov nat64_check_prefix6(const struct in6_addr *prefix, int length) 204d8caf56eSAndrey V. Elsukov { 205d8caf56eSAndrey V. Elsukov 206782360deSAndrey V. Elsukov switch (length) { 207782360deSAndrey V. Elsukov case 32: 208782360deSAndrey V. Elsukov case 40: 209782360deSAndrey V. Elsukov case 48: 210782360deSAndrey V. Elsukov case 56: 211782360deSAndrey V. Elsukov case 64: 212782360deSAndrey V. Elsukov /* Well-known prefix has 96 prefix length */ 213782360deSAndrey V. Elsukov if (IN6_IS_ADDR_WKPFX(prefix)) 214782360deSAndrey V. Elsukov return (EINVAL); 215782360deSAndrey V. Elsukov /* FALLTHROUGH */ 216782360deSAndrey V. Elsukov case 96: 217782360deSAndrey V. Elsukov /* Bits 64 to 71 must be set to zero */ 218782360deSAndrey V. Elsukov if (prefix->__u6_addr.__u6_addr8[8] != 0) 219782360deSAndrey V. Elsukov return (EINVAL); 220782360deSAndrey V. Elsukov /* Some extra checks */ 221782360deSAndrey V. Elsukov if (IN6_IS_ADDR_MULTICAST(prefix) || 222782360deSAndrey V. Elsukov IN6_IS_ADDR_UNSPECIFIED(prefix) || 223782360deSAndrey V. Elsukov IN6_IS_ADDR_LOOPBACK(prefix)) 224782360deSAndrey V. Elsukov return (EINVAL); 225782360deSAndrey V. Elsukov return (0); 226782360deSAndrey V. Elsukov } 227782360deSAndrey V. Elsukov return (EINVAL); 228d8caf56eSAndrey V. Elsukov } 229d8caf56eSAndrey V. Elsukov 230782360deSAndrey V. Elsukov int 231782360deSAndrey V. Elsukov nat64_check_private_ip4(const struct nat64_config *cfg, in_addr_t ia) 232d8caf56eSAndrey V. Elsukov { 233d8caf56eSAndrey V. Elsukov 234782360deSAndrey V. Elsukov if (V_nat64_allow_private) 235782360deSAndrey V. Elsukov return (0); 236782360deSAndrey V. Elsukov 237782360deSAndrey V. Elsukov /* WKPFX must not be used to represent non-global IPv4 addresses */ 238782360deSAndrey V. Elsukov if (cfg->flags & NAT64_WKPFX) { 239782360deSAndrey V. Elsukov /* IN_PRIVATE */ 240782360deSAndrey V. Elsukov if ((ia & htonl(0xff000000)) == htonl(0x0a000000) || 241782360deSAndrey V. Elsukov (ia & htonl(0xfff00000)) == htonl(0xac100000) || 242782360deSAndrey V. Elsukov (ia & htonl(0xffff0000)) == htonl(0xc0a80000)) 243782360deSAndrey V. Elsukov return (1); 244782360deSAndrey V. Elsukov /* 245782360deSAndrey V. Elsukov * RFC 5735: 246782360deSAndrey V. Elsukov * 192.0.0.0/24 - reserved for IETF protocol assignments 247782360deSAndrey V. Elsukov * 192.88.99.0/24 - for use as 6to4 relay anycast addresses 248782360deSAndrey V. Elsukov * 198.18.0.0/15 - for use in benchmark tests 249782360deSAndrey V. Elsukov * 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24 - for use 250782360deSAndrey V. Elsukov * in documentation and example code 251782360deSAndrey V. Elsukov */ 252782360deSAndrey V. Elsukov if ((ia & htonl(0xffffff00)) == htonl(0xc0000000) || 253782360deSAndrey V. Elsukov (ia & htonl(0xffffff00)) == htonl(0xc0586300) || 254782360deSAndrey V. Elsukov (ia & htonl(0xfffffe00)) == htonl(0xc6120000) || 255782360deSAndrey V. Elsukov (ia & htonl(0xffffff00)) == htonl(0xc0000200) || 256782360deSAndrey V. Elsukov (ia & htonl(0xfffffe00)) == htonl(0xc6336400) || 257782360deSAndrey V. Elsukov (ia & htonl(0xffffff00)) == htonl(0xcb007100)) 258782360deSAndrey V. Elsukov return (1); 259782360deSAndrey V. Elsukov } 260782360deSAndrey V. Elsukov return (0); 261782360deSAndrey V. Elsukov } 262782360deSAndrey V. Elsukov 263782360deSAndrey V. Elsukov void 264782360deSAndrey V. Elsukov nat64_embed_ip4(const struct nat64_config *cfg, in_addr_t ia, 265782360deSAndrey V. Elsukov struct in6_addr *ip6) 266782360deSAndrey V. Elsukov { 267782360deSAndrey V. Elsukov 268782360deSAndrey V. Elsukov /* assume the prefix6 is properly filled with zeros */ 269782360deSAndrey V. Elsukov bcopy(&cfg->prefix6, ip6, sizeof(*ip6)); 270782360deSAndrey V. Elsukov switch (cfg->plen6) { 271d8caf56eSAndrey V. Elsukov case 32: 272d8caf56eSAndrey V. Elsukov case 96: 273782360deSAndrey V. Elsukov ip6->s6_addr32[cfg->plen6 / 32] = ia; 274d8caf56eSAndrey V. Elsukov break; 275d8caf56eSAndrey V. Elsukov case 40: 276d8caf56eSAndrey V. Elsukov case 48: 277d8caf56eSAndrey V. Elsukov case 56: 278d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 279782360deSAndrey V. Elsukov ip6->s6_addr32[1] = cfg->prefix6.s6_addr32[1] | 280782360deSAndrey V. Elsukov (ia >> (cfg->plen6 % 32)); 281782360deSAndrey V. Elsukov ip6->s6_addr32[2] = ia << (24 - cfg->plen6 % 32); 282d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 283782360deSAndrey V. Elsukov ip6->s6_addr32[1] = cfg->prefix6.s6_addr32[1] | 284782360deSAndrey V. Elsukov (ia << (cfg->plen6 % 32)); 285782360deSAndrey V. Elsukov ip6->s6_addr32[2] = ia >> (24 - cfg->plen6 % 32); 286d8caf56eSAndrey V. Elsukov #endif 287d8caf56eSAndrey V. Elsukov break; 288d8caf56eSAndrey V. Elsukov case 64: 289d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 290d8caf56eSAndrey V. Elsukov ip6->s6_addr32[2] = ia >> 8; 291d8caf56eSAndrey V. Elsukov ip6->s6_addr32[3] = ia << 24; 292d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 293d8caf56eSAndrey V. Elsukov ip6->s6_addr32[2] = ia << 8; 294d8caf56eSAndrey V. Elsukov ip6->s6_addr32[3] = ia >> 24; 295d8caf56eSAndrey V. Elsukov #endif 296d8caf56eSAndrey V. Elsukov break; 297d8caf56eSAndrey V. Elsukov default: 298782360deSAndrey V. Elsukov panic("Wrong plen6"); 299d8caf56eSAndrey V. Elsukov }; 300d8caf56eSAndrey V. Elsukov ip6->s6_addr8[8] = 0; 301d8caf56eSAndrey V. Elsukov } 302d8caf56eSAndrey V. Elsukov 303782360deSAndrey V. Elsukov in_addr_t 304782360deSAndrey V. Elsukov nat64_extract_ip4(const struct nat64_config *cfg, const struct in6_addr *ip6) 305d8caf56eSAndrey V. Elsukov { 306d8caf56eSAndrey V. Elsukov in_addr_t ia; 307d8caf56eSAndrey V. Elsukov 308d8caf56eSAndrey V. Elsukov /* 309d8caf56eSAndrey V. Elsukov * According to RFC 6052 p2.2: 310d8caf56eSAndrey V. Elsukov * IPv4-embedded IPv6 addresses are composed of a variable-length 311d8caf56eSAndrey V. Elsukov * prefix, the embedded IPv4 address, and a variable length suffix. 312d8caf56eSAndrey V. Elsukov * The suffix bits are reserved for future extensions and SHOULD 313d8caf56eSAndrey V. Elsukov * be set to zero. 314d8caf56eSAndrey V. Elsukov */ 315782360deSAndrey V. Elsukov switch (cfg->plen6) { 316d8caf56eSAndrey V. Elsukov case 32: 317d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || ip6->s6_addr32[2] != 0) 318d8caf56eSAndrey V. Elsukov goto badip6; 319d8caf56eSAndrey V. Elsukov break; 320d8caf56eSAndrey V. Elsukov case 40: 321d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || 322d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[2] & htonl(0xff00ffff)) != 0) 323d8caf56eSAndrey V. Elsukov goto badip6; 324d8caf56eSAndrey V. Elsukov break; 325d8caf56eSAndrey V. Elsukov case 48: 326d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || 327d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[2] & htonl(0xff0000ff)) != 0) 328d8caf56eSAndrey V. Elsukov goto badip6; 329d8caf56eSAndrey V. Elsukov break; 330d8caf56eSAndrey V. Elsukov case 56: 331d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || ip6->s6_addr8[8] != 0) 332d8caf56eSAndrey V. Elsukov goto badip6; 333d8caf56eSAndrey V. Elsukov break; 334d8caf56eSAndrey V. Elsukov case 64: 335d8caf56eSAndrey V. Elsukov if (ip6->s6_addr8[8] != 0 || 336d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[3] & htonl(0x00ffffff)) != 0) 337d8caf56eSAndrey V. Elsukov goto badip6; 338d8caf56eSAndrey V. Elsukov }; 339782360deSAndrey V. Elsukov switch (cfg->plen6) { 340d8caf56eSAndrey V. Elsukov case 32: 341d8caf56eSAndrey V. Elsukov case 96: 342782360deSAndrey V. Elsukov ia = ip6->s6_addr32[cfg->plen6 / 32]; 343d8caf56eSAndrey V. Elsukov break; 344d8caf56eSAndrey V. Elsukov case 40: 345d8caf56eSAndrey V. Elsukov case 48: 346d8caf56eSAndrey V. Elsukov case 56: 347d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 348782360deSAndrey V. Elsukov ia = (ip6->s6_addr32[1] << (cfg->plen6 % 32)) | 349782360deSAndrey V. Elsukov (ip6->s6_addr32[2] >> (24 - cfg->plen6 % 32)); 350d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 351782360deSAndrey V. Elsukov ia = (ip6->s6_addr32[1] >> (cfg->plen6 % 32)) | 352782360deSAndrey V. Elsukov (ip6->s6_addr32[2] << (24 - cfg->plen6 % 32)); 353d8caf56eSAndrey V. Elsukov #endif 354d8caf56eSAndrey V. Elsukov break; 355d8caf56eSAndrey V. Elsukov case 64: 356d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 357d8caf56eSAndrey V. Elsukov ia = (ip6->s6_addr32[2] << 8) | (ip6->s6_addr32[3] >> 24); 358d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 359d8caf56eSAndrey V. Elsukov ia = (ip6->s6_addr32[2] >> 8) | (ip6->s6_addr32[3] << 24); 360d8caf56eSAndrey V. Elsukov #endif 361d8caf56eSAndrey V. Elsukov break; 362d8caf56eSAndrey V. Elsukov default: 363d8caf56eSAndrey V. Elsukov return (0); 364d8caf56eSAndrey V. Elsukov }; 365d8caf56eSAndrey V. Elsukov if (nat64_check_ip4(ia) != 0 || 366782360deSAndrey V. Elsukov nat64_check_private_ip4(cfg, ia) != 0) 367d8caf56eSAndrey V. Elsukov goto badip4; 368d8caf56eSAndrey V. Elsukov 369d8caf56eSAndrey V. Elsukov return (ia); 370d8caf56eSAndrey V. Elsukov badip4: 371782360deSAndrey V. Elsukov DPRINTF(DP_GENERIC | DP_DROPS, 372782360deSAndrey V. Elsukov "invalid destination address: %08x", ia); 373d8caf56eSAndrey V. Elsukov return (0); 374d8caf56eSAndrey V. Elsukov badip6: 375782360deSAndrey V. Elsukov DPRINTF(DP_GENERIC | DP_DROPS, "invalid IPv4-embedded IPv6 address"); 376d8caf56eSAndrey V. Elsukov return (0); 377d8caf56eSAndrey V. Elsukov } 378d8caf56eSAndrey V. Elsukov 379d8caf56eSAndrey V. Elsukov /* 380d8caf56eSAndrey V. Elsukov * According to RFC 1624 the equation for incremental checksum update is: 381d8caf56eSAndrey V. Elsukov * HC' = ~(~HC + ~m + m') -- [Eqn. 3] 382d8caf56eSAndrey V. Elsukov * HC' = HC - ~m - m' -- [Eqn. 4] 383d8caf56eSAndrey V. Elsukov * So, when we are replacing IPv4 addresses to IPv6, we 384d8caf56eSAndrey V. Elsukov * can assume, that new bytes previously were zeros, and vise versa - 385d8caf56eSAndrey V. Elsukov * when we replacing IPv6 addresses to IPv4, now unused bytes become 386d8caf56eSAndrey V. Elsukov * zeros. The payload length in pseudo header has bigger size, but one 387d8caf56eSAndrey V. Elsukov * half of it should be zero. Using the equation 4 we get: 388d8caf56eSAndrey V. Elsukov * HC' = HC - (~m0 + m0') -- m0 is first changed word 389d8caf56eSAndrey V. Elsukov * HC' = (HC - (~m0 + m0')) - (~m1 + m1') -- m1 is second changed word 390d8caf56eSAndrey V. Elsukov * HC' = HC - ~m0 - m0' - ~m1 - m1' - ... = 391d8caf56eSAndrey V. Elsukov * = HC - sum(~m[i] + m'[i]) 392d8caf56eSAndrey V. Elsukov * 393d8caf56eSAndrey V. Elsukov * The function result should be used as follows: 394d8caf56eSAndrey V. Elsukov * IPv6 to IPv4: HC' = cksum_add(HC, result) 395d8caf56eSAndrey V. Elsukov * IPv4 to IPv6: HC' = cksum_add(HC, ~result) 396d8caf56eSAndrey V. Elsukov */ 397c402a01bSAndrey V. Elsukov static NAT64NOINLINE uint16_t 398d8caf56eSAndrey V. Elsukov nat64_cksum_convert(struct ip6_hdr *ip6, struct ip *ip) 399d8caf56eSAndrey V. Elsukov { 400d8caf56eSAndrey V. Elsukov uint32_t sum; 401d8caf56eSAndrey V. Elsukov uint16_t *p; 402d8caf56eSAndrey V. Elsukov 403d8caf56eSAndrey V. Elsukov sum = ~ip->ip_src.s_addr >> 16; 404d8caf56eSAndrey V. Elsukov sum += ~ip->ip_src.s_addr & 0xffff; 405d8caf56eSAndrey V. Elsukov sum += ~ip->ip_dst.s_addr >> 16; 406d8caf56eSAndrey V. Elsukov sum += ~ip->ip_dst.s_addr & 0xffff; 407d8caf56eSAndrey V. Elsukov 408d8caf56eSAndrey V. Elsukov for (p = (uint16_t *)&ip6->ip6_src; 409d8caf56eSAndrey V. Elsukov p < (uint16_t *)(&ip6->ip6_src + 2); p++) 410d8caf56eSAndrey V. Elsukov sum += *p; 411d8caf56eSAndrey V. Elsukov 412d8caf56eSAndrey V. Elsukov while (sum >> 16) 413d8caf56eSAndrey V. Elsukov sum = (sum & 0xffff) + (sum >> 16); 414d8caf56eSAndrey V. Elsukov return (sum); 415d8caf56eSAndrey V. Elsukov } 416d8caf56eSAndrey V. Elsukov 417c402a01bSAndrey V. Elsukov static NAT64NOINLINE void 418d8caf56eSAndrey V. Elsukov nat64_init_ip4hdr(const struct ip6_hdr *ip6, const struct ip6_frag *frag, 419d8caf56eSAndrey V. Elsukov uint16_t plen, uint8_t proto, struct ip *ip) 420d8caf56eSAndrey V. Elsukov { 421d8caf56eSAndrey V. Elsukov 422d8caf56eSAndrey V. Elsukov /* assume addresses are already initialized */ 423d8caf56eSAndrey V. Elsukov ip->ip_v = IPVERSION; 424d8caf56eSAndrey V. Elsukov ip->ip_hl = sizeof(*ip) >> 2; 425d8caf56eSAndrey V. Elsukov ip->ip_tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 426d8caf56eSAndrey V. Elsukov ip->ip_len = htons(sizeof(*ip) + plen); 427d8caf56eSAndrey V. Elsukov #ifdef IPFIREWALL_NAT64_DIRECT_OUTPUT 428d8caf56eSAndrey V. Elsukov ip->ip_ttl = ip6->ip6_hlim - IPV6_HLIMDEC; 429d8caf56eSAndrey V. Elsukov #else 430d8caf56eSAndrey V. Elsukov /* Forwarding code will decrement TTL. */ 431d8caf56eSAndrey V. Elsukov ip->ip_ttl = ip6->ip6_hlim; 432d8caf56eSAndrey V. Elsukov #endif 433d8caf56eSAndrey V. Elsukov ip->ip_sum = 0; 434d8caf56eSAndrey V. Elsukov ip->ip_p = (proto == IPPROTO_ICMPV6) ? IPPROTO_ICMP: proto; 435d8caf56eSAndrey V. Elsukov ip_fillid(ip); 436d8caf56eSAndrey V. Elsukov if (frag != NULL) { 437d8caf56eSAndrey V. Elsukov ip->ip_off = htons(ntohs(frag->ip6f_offlg) >> 3); 438d8caf56eSAndrey V. Elsukov if (frag->ip6f_offlg & IP6F_MORE_FRAG) 439d8caf56eSAndrey V. Elsukov ip->ip_off |= htons(IP_MF); 440d8caf56eSAndrey V. Elsukov } else { 441d8caf56eSAndrey V. Elsukov ip->ip_off = htons(IP_DF); 442d8caf56eSAndrey V. Elsukov } 443d8caf56eSAndrey V. Elsukov ip->ip_sum = in_cksum_hdr(ip); 444d8caf56eSAndrey V. Elsukov } 445d8caf56eSAndrey V. Elsukov 446d8caf56eSAndrey V. Elsukov #define FRAGSZ(mtu) ((mtu) - sizeof(struct ip6_hdr) - sizeof(struct ip6_frag)) 447c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 448782360deSAndrey V. Elsukov nat64_fragment6(struct nat64_counters *stats, struct ip6_hdr *ip6, 449782360deSAndrey V. Elsukov struct mbufq *mq, struct mbuf *m, uint32_t mtu, uint16_t ip_id, 450782360deSAndrey V. Elsukov uint16_t ip_off) 451d8caf56eSAndrey V. Elsukov { 452d8caf56eSAndrey V. Elsukov struct ip6_frag ip6f; 453d8caf56eSAndrey V. Elsukov struct mbuf *n; 454d8caf56eSAndrey V. Elsukov uint16_t hlen, len, offset; 455d8caf56eSAndrey V. Elsukov int plen; 456d8caf56eSAndrey V. Elsukov 457d8caf56eSAndrey V. Elsukov plen = ntohs(ip6->ip6_plen); 458d8caf56eSAndrey V. Elsukov hlen = sizeof(struct ip6_hdr); 459d8caf56eSAndrey V. Elsukov 460d8caf56eSAndrey V. Elsukov /* Fragmentation isn't needed */ 461d8caf56eSAndrey V. Elsukov if (ip_off == 0 && plen <= mtu - hlen) { 462d8caf56eSAndrey V. Elsukov M_PREPEND(m, hlen, M_NOWAIT); 463d8caf56eSAndrey V. Elsukov if (m == NULL) { 464d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 465d8caf56eSAndrey V. Elsukov return (ENOMEM); 466d8caf56eSAndrey V. Elsukov } 467d8caf56eSAndrey V. Elsukov bcopy(ip6, mtod(m, void *), hlen); 468d8caf56eSAndrey V. Elsukov if (mbufq_enqueue(mq, m) != 0) { 469d8caf56eSAndrey V. Elsukov m_freem(m); 470d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 471d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to mbufq overflow"); 472d8caf56eSAndrey V. Elsukov return (ENOBUFS); 473d8caf56eSAndrey V. Elsukov } 474d8caf56eSAndrey V. Elsukov return (0); 475d8caf56eSAndrey V. Elsukov } 476d8caf56eSAndrey V. Elsukov 477d8caf56eSAndrey V. Elsukov hlen += sizeof(struct ip6_frag); 478d8caf56eSAndrey V. Elsukov ip6f.ip6f_reserved = 0; 479d8caf56eSAndrey V. Elsukov ip6f.ip6f_nxt = ip6->ip6_nxt; 480d8caf56eSAndrey V. Elsukov ip6->ip6_nxt = IPPROTO_FRAGMENT; 481d8caf56eSAndrey V. Elsukov if (ip_off != 0) { 482d8caf56eSAndrey V. Elsukov /* 483d8caf56eSAndrey V. Elsukov * We have got an IPv4 fragment. 484d8caf56eSAndrey V. Elsukov * Use offset value and ip_id from original fragment. 485d8caf56eSAndrey V. Elsukov */ 486d8caf56eSAndrey V. Elsukov ip6f.ip6f_ident = htonl(ntohs(ip_id)); 487d8caf56eSAndrey V. Elsukov offset = (ntohs(ip_off) & IP_OFFMASK) << 3; 488d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, ifrags); 489d8caf56eSAndrey V. Elsukov } else { 490d8caf56eSAndrey V. Elsukov /* The packet size exceeds interface MTU */ 491d8caf56eSAndrey V. Elsukov ip6f.ip6f_ident = htonl(ip6_randomid()); 492d8caf56eSAndrey V. Elsukov offset = 0; /* First fragment*/ 493d8caf56eSAndrey V. Elsukov } 494d8caf56eSAndrey V. Elsukov while (plen > 0 && m != NULL) { 495d8caf56eSAndrey V. Elsukov n = NULL; 496d8caf56eSAndrey V. Elsukov len = FRAGSZ(mtu) & ~7; 497d8caf56eSAndrey V. Elsukov if (len > plen) 498d8caf56eSAndrey V. Elsukov len = plen; 499d8caf56eSAndrey V. Elsukov ip6->ip6_plen = htons(len + sizeof(ip6f)); 500d8caf56eSAndrey V. Elsukov ip6f.ip6f_offlg = ntohs(offset); 501d8caf56eSAndrey V. Elsukov if (len < plen || (ip_off & htons(IP_MF)) != 0) 502d8caf56eSAndrey V. Elsukov ip6f.ip6f_offlg |= IP6F_MORE_FRAG; 503d8caf56eSAndrey V. Elsukov offset += len; 504d8caf56eSAndrey V. Elsukov plen -= len; 505d8caf56eSAndrey V. Elsukov if (plen > 0) { 506d8caf56eSAndrey V. Elsukov n = m_split(m, len, M_NOWAIT); 507d8caf56eSAndrey V. Elsukov if (n == NULL) 508d8caf56eSAndrey V. Elsukov goto fail; 509d8caf56eSAndrey V. Elsukov } 510d8caf56eSAndrey V. Elsukov M_PREPEND(m, hlen, M_NOWAIT); 511d8caf56eSAndrey V. Elsukov if (m == NULL) 512d8caf56eSAndrey V. Elsukov goto fail; 513d8caf56eSAndrey V. Elsukov bcopy(ip6, mtod(m, void *), sizeof(struct ip6_hdr)); 514d8caf56eSAndrey V. Elsukov bcopy(&ip6f, mtodo(m, sizeof(struct ip6_hdr)), 515d8caf56eSAndrey V. Elsukov sizeof(struct ip6_frag)); 516d8caf56eSAndrey V. Elsukov if (mbufq_enqueue(mq, m) != 0) 517d8caf56eSAndrey V. Elsukov goto fail; 518d8caf56eSAndrey V. Elsukov m = n; 519d8caf56eSAndrey V. Elsukov } 520d8caf56eSAndrey V. Elsukov NAT64STAT_ADD(stats, ofrags, mbufq_len(mq)); 521d8caf56eSAndrey V. Elsukov return (0); 522d8caf56eSAndrey V. Elsukov fail: 523d8caf56eSAndrey V. Elsukov if (m != NULL) 524d8caf56eSAndrey V. Elsukov m_freem(m); 525d8caf56eSAndrey V. Elsukov if (n != NULL) 526d8caf56eSAndrey V. Elsukov m_freem(n); 527d8caf56eSAndrey V. Elsukov mbufq_drain(mq); 528d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 529d8caf56eSAndrey V. Elsukov return (ENOMEM); 530d8caf56eSAndrey V. Elsukov } 531d8caf56eSAndrey V. Elsukov 532c570565fSAndrey V. Elsukov static NAT64NOINLINE int 533c570565fSAndrey V. Elsukov nat64_find_route6(struct nhop6_basic *pnh, struct sockaddr_in6 *dst, 534c570565fSAndrey V. Elsukov struct mbuf *m) 535d8caf56eSAndrey V. Elsukov { 536d8caf56eSAndrey V. Elsukov 537c570565fSAndrey V. Elsukov if (fib6_lookup_nh_basic(M_GETFIB(m), &dst->sin6_addr, 0, 0, 0, 538c570565fSAndrey V. Elsukov pnh) != 0) 539c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 540c570565fSAndrey V. Elsukov if (pnh->nh_flags & (NHF_BLACKHOLE | NHF_REJECT)) 541c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 542c570565fSAndrey V. Elsukov /* 543c570565fSAndrey V. Elsukov * XXX: we need to use destination address with embedded scope 544c570565fSAndrey V. Elsukov * zone id, because LLTABLE uses such form of addresses for lookup. 545c570565fSAndrey V. Elsukov */ 546d8caf56eSAndrey V. Elsukov dst->sin6_family = AF_INET6; 547d8caf56eSAndrey V. Elsukov dst->sin6_len = sizeof(*dst); 548c570565fSAndrey V. Elsukov dst->sin6_addr = pnh->nh_addr; 549c570565fSAndrey V. Elsukov if (IN6_IS_SCOPE_LINKLOCAL(&dst->sin6_addr)) 550c570565fSAndrey V. Elsukov dst->sin6_addr.s6_addr16[1] = 551c570565fSAndrey V. Elsukov htons(pnh->nh_ifp->if_index & 0xffff); 552c570565fSAndrey V. Elsukov dst->sin6_port = 0; 553c570565fSAndrey V. Elsukov dst->sin6_scope_id = 0; 554c570565fSAndrey V. Elsukov dst->sin6_flowinfo = 0; 555c570565fSAndrey V. Elsukov 556c570565fSAndrey V. Elsukov return (0); 557d8caf56eSAndrey V. Elsukov } 558d8caf56eSAndrey V. Elsukov 559d8caf56eSAndrey V. Elsukov #define NAT64_ICMP6_PLEN 64 560c402a01bSAndrey V. Elsukov static NAT64NOINLINE void 561d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(struct mbuf *m, uint8_t type, uint8_t code, uint32_t mtu, 562782360deSAndrey V. Elsukov struct nat64_counters *stats, void *logdata) 563d8caf56eSAndrey V. Elsukov { 564d8caf56eSAndrey V. Elsukov struct icmp6_hdr *icmp6; 565d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6, *oip6; 566d8caf56eSAndrey V. Elsukov struct mbuf *n; 567d8caf56eSAndrey V. Elsukov int len, plen; 568d8caf56eSAndrey V. Elsukov 569d8caf56eSAndrey V. Elsukov len = 0; 570d8caf56eSAndrey V. Elsukov plen = nat64_getlasthdr(m, &len); 571d8caf56eSAndrey V. Elsukov if (plen < 0) { 572d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "mbuf isn't contigious"); 573d8caf56eSAndrey V. Elsukov goto freeit; 574d8caf56eSAndrey V. Elsukov } 575d8caf56eSAndrey V. Elsukov /* 576d8caf56eSAndrey V. Elsukov * Do not send ICMPv6 in reply to ICMPv6 errors. 577d8caf56eSAndrey V. Elsukov */ 578d8caf56eSAndrey V. Elsukov if (plen == IPPROTO_ICMPV6) { 579d8caf56eSAndrey V. Elsukov if (m->m_len < len + sizeof(*icmp6)) { 580d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "mbuf isn't contigious"); 581d8caf56eSAndrey V. Elsukov goto freeit; 582d8caf56eSAndrey V. Elsukov } 583d8caf56eSAndrey V. Elsukov icmp6 = mtodo(m, len); 584d8caf56eSAndrey V. Elsukov if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST || 585d8caf56eSAndrey V. Elsukov icmp6->icmp6_type == ND_REDIRECT) { 586d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "do not send ICMPv6 in reply to " 587d8caf56eSAndrey V. Elsukov "ICMPv6 errors"); 588d8caf56eSAndrey V. Elsukov goto freeit; 589d8caf56eSAndrey V. Elsukov } 590d8caf56eSAndrey V. Elsukov } 591d8caf56eSAndrey V. Elsukov /* 592d8caf56eSAndrey V. Elsukov if (icmp6_ratelimit(&ip6->ip6_src, type, code)) 593d8caf56eSAndrey V. Elsukov goto freeit; 594d8caf56eSAndrey V. Elsukov */ 595d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 596d8caf56eSAndrey V. Elsukov switch (type) { 597d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH: 598d8caf56eSAndrey V. Elsukov case ICMP6_PACKET_TOO_BIG: 599d8caf56eSAndrey V. Elsukov case ICMP6_TIME_EXCEEDED: 600d8caf56eSAndrey V. Elsukov case ICMP6_PARAM_PROB: 601d8caf56eSAndrey V. Elsukov break; 602d8caf56eSAndrey V. Elsukov default: 603d8caf56eSAndrey V. Elsukov goto freeit; 604d8caf56eSAndrey V. Elsukov } 605d8caf56eSAndrey V. Elsukov /* Calculate length of ICMPv6 payload */ 606d8caf56eSAndrey V. Elsukov len = (m->m_pkthdr.len > NAT64_ICMP6_PLEN) ? NAT64_ICMP6_PLEN: 607d8caf56eSAndrey V. Elsukov m->m_pkthdr.len; 608d8caf56eSAndrey V. Elsukov 609d8caf56eSAndrey V. Elsukov /* Create new ICMPv6 datagram */ 610d8caf56eSAndrey V. Elsukov plen = len + sizeof(struct icmp6_hdr); 611d8caf56eSAndrey V. Elsukov n = m_get2(sizeof(struct ip6_hdr) + plen + max_hdr, M_NOWAIT, 612d8caf56eSAndrey V. Elsukov MT_HEADER, M_PKTHDR); 613d8caf56eSAndrey V. Elsukov if (n == NULL) { 614d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 615d8caf56eSAndrey V. Elsukov m_freem(m); 616d8caf56eSAndrey V. Elsukov return; 617d8caf56eSAndrey V. Elsukov } 618d8caf56eSAndrey V. Elsukov /* 619d8caf56eSAndrey V. Elsukov * Move pkthdr from original mbuf. We should have initialized some 620d8caf56eSAndrey V. Elsukov * fields, because we can reinject this mbuf to netisr and it will 621d8caf56eSAndrey V. Elsukov * go trough input path (it requires at least rcvif should be set). 622d8caf56eSAndrey V. Elsukov * Also do M_ALIGN() to reduce chances of need to allocate new mbuf 623d8caf56eSAndrey V. Elsukov * in the chain, when we will do M_PREPEND() or make some type of 624d8caf56eSAndrey V. Elsukov * tunneling. 625d8caf56eSAndrey V. Elsukov */ 626d8caf56eSAndrey V. Elsukov m_move_pkthdr(n, m); 627d8caf56eSAndrey V. Elsukov M_ALIGN(n, sizeof(struct ip6_hdr) + plen + max_hdr); 628d8caf56eSAndrey V. Elsukov 629d8caf56eSAndrey V. Elsukov n->m_len = n->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 630d8caf56eSAndrey V. Elsukov oip6 = mtod(n, struct ip6_hdr *); 631d8caf56eSAndrey V. Elsukov oip6->ip6_src = ip6->ip6_dst; 632d8caf56eSAndrey V. Elsukov oip6->ip6_dst = ip6->ip6_src; 633d8caf56eSAndrey V. Elsukov oip6->ip6_nxt = IPPROTO_ICMPV6; 634d8caf56eSAndrey V. Elsukov oip6->ip6_flow = 0; 635d8caf56eSAndrey V. Elsukov oip6->ip6_vfc |= IPV6_VERSION; 636d8caf56eSAndrey V. Elsukov oip6->ip6_hlim = V_ip6_defhlim; 637d8caf56eSAndrey V. Elsukov oip6->ip6_plen = htons(plen); 638d8caf56eSAndrey V. Elsukov 639d8caf56eSAndrey V. Elsukov icmp6 = mtodo(n, sizeof(struct ip6_hdr)); 640d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = 0; 641d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = type; 642d8caf56eSAndrey V. Elsukov icmp6->icmp6_code = code; 643d8caf56eSAndrey V. Elsukov icmp6->icmp6_mtu = htonl(mtu); 644d8caf56eSAndrey V. Elsukov 645d8caf56eSAndrey V. Elsukov m_copydata(m, 0, len, mtodo(n, sizeof(struct ip6_hdr) + 646d8caf56eSAndrey V. Elsukov sizeof(struct icmp6_hdr))); 647d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = in6_cksum(n, IPPROTO_ICMPV6, 648d8caf56eSAndrey V. Elsukov sizeof(struct ip6_hdr), plen); 649d8caf56eSAndrey V. Elsukov m_freem(m); 650d8caf56eSAndrey V. Elsukov nat64_output_one(n, stats, logdata); 651d8caf56eSAndrey V. Elsukov return; 652d8caf56eSAndrey V. Elsukov freeit: 653d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 654d8caf56eSAndrey V. Elsukov m_freem(m); 655d8caf56eSAndrey V. Elsukov } 656d8caf56eSAndrey V. Elsukov 657c570565fSAndrey V. Elsukov static NAT64NOINLINE int 658c570565fSAndrey V. Elsukov nat64_find_route4(struct nhop4_basic *pnh, struct sockaddr_in *dst, 659c570565fSAndrey V. Elsukov struct mbuf *m) 660d8caf56eSAndrey V. Elsukov { 661d8caf56eSAndrey V. Elsukov 662c570565fSAndrey V. Elsukov if (fib4_lookup_nh_basic(M_GETFIB(m), dst->sin_addr, 0, 0, pnh) != 0) 663c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 664c570565fSAndrey V. Elsukov if (pnh->nh_flags & (NHF_BLACKHOLE | NHF_BROADCAST | NHF_REJECT)) 665c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 666c570565fSAndrey V. Elsukov 667d8caf56eSAndrey V. Elsukov dst->sin_family = AF_INET; 668d8caf56eSAndrey V. Elsukov dst->sin_len = sizeof(*dst); 669c570565fSAndrey V. Elsukov dst->sin_addr = pnh->nh_addr; 670c570565fSAndrey V. Elsukov dst->sin_port = 0; 671c570565fSAndrey V. Elsukov return (0); 672d8caf56eSAndrey V. Elsukov } 673d8caf56eSAndrey V. Elsukov 674d8caf56eSAndrey V. Elsukov #define NAT64_ICMP_PLEN 64 675c402a01bSAndrey V. Elsukov static NAT64NOINLINE void 676d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(struct mbuf *m, uint8_t type, 677782360deSAndrey V. Elsukov uint8_t code, uint16_t mtu, struct nat64_counters *stats, void *logdata) 678d8caf56eSAndrey V. Elsukov { 679d8caf56eSAndrey V. Elsukov struct icmp *icmp; 680d8caf56eSAndrey V. Elsukov struct ip *ip, *oip; 681d8caf56eSAndrey V. Elsukov struct mbuf *n; 682d8caf56eSAndrey V. Elsukov int len, plen; 683d8caf56eSAndrey V. Elsukov 684d8caf56eSAndrey V. Elsukov ip = mtod(m, struct ip *); 685d8caf56eSAndrey V. Elsukov /* Do not send ICMP error if packet is not the first fragment */ 686d8caf56eSAndrey V. Elsukov if (ip->ip_off & ~ntohs(IP_MF|IP_DF)) { 687d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "not first fragment"); 688d8caf56eSAndrey V. Elsukov goto freeit; 689d8caf56eSAndrey V. Elsukov } 690d8caf56eSAndrey V. Elsukov /* Do not send ICMP in reply to ICMP errors */ 691d8caf56eSAndrey V. Elsukov if (ip->ip_p == IPPROTO_ICMP) { 692d8caf56eSAndrey V. Elsukov if (m->m_len < (ip->ip_hl << 2)) { 693d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "mbuf isn't contigious"); 694d8caf56eSAndrey V. Elsukov goto freeit; 695d8caf56eSAndrey V. Elsukov } 696d8caf56eSAndrey V. Elsukov icmp = mtodo(m, ip->ip_hl << 2); 697d8caf56eSAndrey V. Elsukov if (!ICMP_INFOTYPE(icmp->icmp_type)) { 698d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "do not send ICMP in reply to " 699d8caf56eSAndrey V. Elsukov "ICMP errors"); 700d8caf56eSAndrey V. Elsukov goto freeit; 701d8caf56eSAndrey V. Elsukov } 702d8caf56eSAndrey V. Elsukov } 703d8caf56eSAndrey V. Elsukov switch (type) { 704d8caf56eSAndrey V. Elsukov case ICMP_UNREACH: 705d8caf56eSAndrey V. Elsukov case ICMP_TIMXCEED: 706d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB: 707d8caf56eSAndrey V. Elsukov break; 708d8caf56eSAndrey V. Elsukov default: 709d8caf56eSAndrey V. Elsukov goto freeit; 710d8caf56eSAndrey V. Elsukov } 711d8caf56eSAndrey V. Elsukov /* Calculate length of ICMP payload */ 712d8caf56eSAndrey V. Elsukov len = (m->m_pkthdr.len > NAT64_ICMP_PLEN) ? (ip->ip_hl << 2) + 8: 713d8caf56eSAndrey V. Elsukov m->m_pkthdr.len; 714d8caf56eSAndrey V. Elsukov 715d8caf56eSAndrey V. Elsukov /* Create new ICMPv4 datagram */ 716d8caf56eSAndrey V. Elsukov plen = len + sizeof(struct icmphdr) + sizeof(uint32_t); 717d8caf56eSAndrey V. Elsukov n = m_get2(sizeof(struct ip) + plen + max_hdr, M_NOWAIT, 718d8caf56eSAndrey V. Elsukov MT_HEADER, M_PKTHDR); 719d8caf56eSAndrey V. Elsukov if (n == NULL) { 720d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 721d8caf56eSAndrey V. Elsukov m_freem(m); 722d8caf56eSAndrey V. Elsukov return; 723d8caf56eSAndrey V. Elsukov } 724d8caf56eSAndrey V. Elsukov m_move_pkthdr(n, m); 725d8caf56eSAndrey V. Elsukov M_ALIGN(n, sizeof(struct ip) + plen + max_hdr); 726d8caf56eSAndrey V. Elsukov 727d8caf56eSAndrey V. Elsukov n->m_len = n->m_pkthdr.len = sizeof(struct ip) + plen; 728d8caf56eSAndrey V. Elsukov oip = mtod(n, struct ip *); 729d8caf56eSAndrey V. Elsukov oip->ip_v = IPVERSION; 730d8caf56eSAndrey V. Elsukov oip->ip_hl = sizeof(struct ip) >> 2; 731d8caf56eSAndrey V. Elsukov oip->ip_tos = 0; 732d8caf56eSAndrey V. Elsukov oip->ip_len = htons(n->m_pkthdr.len); 733d8caf56eSAndrey V. Elsukov oip->ip_ttl = V_ip_defttl; 734d8caf56eSAndrey V. Elsukov oip->ip_p = IPPROTO_ICMP; 735d8caf56eSAndrey V. Elsukov ip_fillid(oip); 736d8caf56eSAndrey V. Elsukov oip->ip_off = htons(IP_DF); 737d8caf56eSAndrey V. Elsukov oip->ip_src = ip->ip_dst; 738d8caf56eSAndrey V. Elsukov oip->ip_dst = ip->ip_src; 739d8caf56eSAndrey V. Elsukov oip->ip_sum = 0; 740d8caf56eSAndrey V. Elsukov oip->ip_sum = in_cksum_hdr(oip); 741d8caf56eSAndrey V. Elsukov 742d8caf56eSAndrey V. Elsukov icmp = mtodo(n, sizeof(struct ip)); 743d8caf56eSAndrey V. Elsukov icmp->icmp_type = type; 744d8caf56eSAndrey V. Elsukov icmp->icmp_code = code; 745d8caf56eSAndrey V. Elsukov icmp->icmp_cksum = 0; 746d8caf56eSAndrey V. Elsukov icmp->icmp_pmvoid = 0; 747d8caf56eSAndrey V. Elsukov icmp->icmp_nextmtu = htons(mtu); 748d8caf56eSAndrey V. Elsukov m_copydata(m, 0, len, mtodo(n, sizeof(struct ip) + 749d8caf56eSAndrey V. Elsukov sizeof(struct icmphdr) + sizeof(uint32_t))); 750d8caf56eSAndrey V. Elsukov icmp->icmp_cksum = in_cksum_skip(n, sizeof(struct ip) + plen, 751d8caf56eSAndrey V. Elsukov sizeof(struct ip)); 752d8caf56eSAndrey V. Elsukov m_freem(m); 753d8caf56eSAndrey V. Elsukov nat64_output_one(n, stats, logdata); 754d8caf56eSAndrey V. Elsukov return; 755d8caf56eSAndrey V. Elsukov freeit: 756d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 757d8caf56eSAndrey V. Elsukov m_freem(m); 758d8caf56eSAndrey V. Elsukov } 759d8caf56eSAndrey V. Elsukov 760d8caf56eSAndrey V. Elsukov /* Translate ICMP echo request/reply into ICMPv6 */ 761d8caf56eSAndrey V. Elsukov static void 762d8caf56eSAndrey V. Elsukov nat64_icmp_handle_echo(struct ip6_hdr *ip6, struct icmp6_hdr *icmp6, 763d8caf56eSAndrey V. Elsukov uint16_t id, uint8_t type) 764d8caf56eSAndrey V. Elsukov { 765d8caf56eSAndrey V. Elsukov uint16_t old; 766d8caf56eSAndrey V. Elsukov 767d8caf56eSAndrey V. Elsukov old = *(uint16_t *)icmp6; /* save type+code in one word */ 768d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = type; 769d8caf56eSAndrey V. Elsukov /* Reflect ICMPv6 -> ICMPv4 type translation in the cksum */ 770d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = cksum_adjust(icmp6->icmp6_cksum, 771d8caf56eSAndrey V. Elsukov old, *(uint16_t *)icmp6); 772d8caf56eSAndrey V. Elsukov if (id != 0) { 773d8caf56eSAndrey V. Elsukov old = icmp6->icmp6_id; 774d8caf56eSAndrey V. Elsukov icmp6->icmp6_id = id; 775d8caf56eSAndrey V. Elsukov /* Reflect ICMP id translation in the cksum */ 776d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = cksum_adjust(icmp6->icmp6_cksum, 777d8caf56eSAndrey V. Elsukov old, id); 778d8caf56eSAndrey V. Elsukov } 779d8caf56eSAndrey V. Elsukov /* Reflect IPv6 pseudo header in the cksum */ 780d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = ~in6_cksum_pseudo(ip6, ntohs(ip6->ip6_plen), 781d8caf56eSAndrey V. Elsukov IPPROTO_ICMPV6, ~icmp6->icmp6_cksum); 782d8caf56eSAndrey V. Elsukov } 783d8caf56eSAndrey V. Elsukov 784c402a01bSAndrey V. Elsukov static NAT64NOINLINE struct mbuf * 785d8caf56eSAndrey V. Elsukov nat64_icmp_translate(struct mbuf *m, struct ip6_hdr *ip6, uint16_t icmpid, 786782360deSAndrey V. Elsukov int offset, struct nat64_config *cfg) 787d8caf56eSAndrey V. Elsukov { 788d8caf56eSAndrey V. Elsukov struct ip ip; 789d8caf56eSAndrey V. Elsukov struct icmp *icmp; 790d8caf56eSAndrey V. Elsukov struct tcphdr *tcp; 791d8caf56eSAndrey V. Elsukov struct udphdr *udp; 792d8caf56eSAndrey V. Elsukov struct ip6_hdr *eip6; 793d8caf56eSAndrey V. Elsukov struct mbuf *n; 794d8caf56eSAndrey V. Elsukov uint32_t mtu; 795d8caf56eSAndrey V. Elsukov int len, hlen, plen; 796d8caf56eSAndrey V. Elsukov uint8_t type, code; 797d8caf56eSAndrey V. Elsukov 798d8caf56eSAndrey V. Elsukov if (m->m_len < offset + ICMP_MINLEN) 799d8caf56eSAndrey V. Elsukov m = m_pullup(m, offset + ICMP_MINLEN); 800d8caf56eSAndrey V. Elsukov if (m == NULL) { 801782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, nomem); 802d8caf56eSAndrey V. Elsukov return (m); 803d8caf56eSAndrey V. Elsukov } 804d8caf56eSAndrey V. Elsukov mtu = 0; 805d8caf56eSAndrey V. Elsukov icmp = mtodo(m, offset); 806d8caf56eSAndrey V. Elsukov /* RFC 7915 p4.2 */ 807d8caf56eSAndrey V. Elsukov switch (icmp->icmp_type) { 808d8caf56eSAndrey V. Elsukov case ICMP_ECHOREPLY: 809d8caf56eSAndrey V. Elsukov type = ICMP6_ECHO_REPLY; 810d8caf56eSAndrey V. Elsukov code = 0; 811d8caf56eSAndrey V. Elsukov break; 812d8caf56eSAndrey V. Elsukov case ICMP_UNREACH: 813d8caf56eSAndrey V. Elsukov type = ICMP6_DST_UNREACH; 814d8caf56eSAndrey V. Elsukov switch (icmp->icmp_code) { 815d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NET: 816d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_HOST: 817d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_SRCFAIL: 818d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NET_UNKNOWN: 819d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_HOST_UNKNOWN: 820d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_TOSNET: 821d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_TOSHOST: 822d8caf56eSAndrey V. Elsukov code = ICMP6_DST_UNREACH_NOROUTE; 823d8caf56eSAndrey V. Elsukov break; 824d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_PROTOCOL: 825d8caf56eSAndrey V. Elsukov type = ICMP6_PARAM_PROB; 826d8caf56eSAndrey V. Elsukov code = ICMP6_PARAMPROB_NEXTHEADER; 827d8caf56eSAndrey V. Elsukov break; 828d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_PORT: 829d8caf56eSAndrey V. Elsukov code = ICMP6_DST_UNREACH_NOPORT; 830d8caf56eSAndrey V. Elsukov break; 831d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NEEDFRAG: 832d8caf56eSAndrey V. Elsukov type = ICMP6_PACKET_TOO_BIG; 833d8caf56eSAndrey V. Elsukov code = 0; 834d8caf56eSAndrey V. Elsukov /* XXX: needs an additional look */ 835d8caf56eSAndrey V. Elsukov mtu = max(IPV6_MMTU, ntohs(icmp->icmp_nextmtu) + 20); 836d8caf56eSAndrey V. Elsukov break; 837d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NET_PROHIB: 838d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_HOST_PROHIB: 839d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_FILTER_PROHIB: 840d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_PRECEDENCE_CUTOFF: 841d8caf56eSAndrey V. Elsukov code = ICMP6_DST_UNREACH_ADMIN; 842d8caf56eSAndrey V. Elsukov break; 843d8caf56eSAndrey V. Elsukov default: 844d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d, code %d", 845d8caf56eSAndrey V. Elsukov icmp->icmp_type, icmp->icmp_code); 846d8caf56eSAndrey V. Elsukov goto freeit; 847d8caf56eSAndrey V. Elsukov } 848d8caf56eSAndrey V. Elsukov break; 849d8caf56eSAndrey V. Elsukov case ICMP_TIMXCEED: 850d8caf56eSAndrey V. Elsukov type = ICMP6_TIME_EXCEEDED; 851d8caf56eSAndrey V. Elsukov code = icmp->icmp_code; 852d8caf56eSAndrey V. Elsukov break; 853d8caf56eSAndrey V. Elsukov case ICMP_ECHO: 854d8caf56eSAndrey V. Elsukov type = ICMP6_ECHO_REQUEST; 855d8caf56eSAndrey V. Elsukov code = 0; 856d8caf56eSAndrey V. Elsukov break; 857d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB: 858d8caf56eSAndrey V. Elsukov type = ICMP6_PARAM_PROB; 859d8caf56eSAndrey V. Elsukov switch (icmp->icmp_code) { 860d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB_ERRATPTR: 861d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB_LENGTH: 862d8caf56eSAndrey V. Elsukov code = ICMP6_PARAMPROB_HEADER; 863d8caf56eSAndrey V. Elsukov switch (icmp->icmp_pptr) { 864d8caf56eSAndrey V. Elsukov case 0: /* Version/IHL */ 865d8caf56eSAndrey V. Elsukov case 1: /* Type Of Service */ 866d8caf56eSAndrey V. Elsukov mtu = icmp->icmp_pptr; 867d8caf56eSAndrey V. Elsukov break; 868d8caf56eSAndrey V. Elsukov case 2: /* Total Length */ 869d8caf56eSAndrey V. Elsukov case 3: mtu = 4; /* Payload Length */ 870d8caf56eSAndrey V. Elsukov break; 871d8caf56eSAndrey V. Elsukov case 8: /* Time to Live */ 872d8caf56eSAndrey V. Elsukov mtu = 7; /* Hop Limit */ 873d8caf56eSAndrey V. Elsukov break; 874d8caf56eSAndrey V. Elsukov case 9: /* Protocol */ 875d8caf56eSAndrey V. Elsukov mtu = 6; /* Next Header */ 876d8caf56eSAndrey V. Elsukov break; 877d8caf56eSAndrey V. Elsukov case 12: /* Source address */ 878d8caf56eSAndrey V. Elsukov case 13: 879d8caf56eSAndrey V. Elsukov case 14: 880d8caf56eSAndrey V. Elsukov case 15: 881d8caf56eSAndrey V. Elsukov mtu = 8; 882d8caf56eSAndrey V. Elsukov break; 883d8caf56eSAndrey V. Elsukov case 16: /* Destination address */ 884d8caf56eSAndrey V. Elsukov case 17: 885d8caf56eSAndrey V. Elsukov case 18: 886d8caf56eSAndrey V. Elsukov case 19: 887d8caf56eSAndrey V. Elsukov mtu = 24; 888d8caf56eSAndrey V. Elsukov break; 889d8caf56eSAndrey V. Elsukov default: /* Silently drop */ 890d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d," 891d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp->icmp_type, 892d8caf56eSAndrey V. Elsukov icmp->icmp_code, icmp->icmp_pptr); 893d8caf56eSAndrey V. Elsukov goto freeit; 894d8caf56eSAndrey V. Elsukov } 895d8caf56eSAndrey V. Elsukov break; 896d8caf56eSAndrey V. Elsukov default: 897d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d," 898d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp->icmp_type, 899d8caf56eSAndrey V. Elsukov icmp->icmp_code, icmp->icmp_pptr); 900d8caf56eSAndrey V. Elsukov goto freeit; 901d8caf56eSAndrey V. Elsukov } 902d8caf56eSAndrey V. Elsukov break; 903d8caf56eSAndrey V. Elsukov default: 904d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d, code %d", 905d8caf56eSAndrey V. Elsukov icmp->icmp_type, icmp->icmp_code); 906d8caf56eSAndrey V. Elsukov goto freeit; 907d8caf56eSAndrey V. Elsukov } 908d8caf56eSAndrey V. Elsukov /* 909d8caf56eSAndrey V. Elsukov * For echo request/reply we can use original payload, 910d8caf56eSAndrey V. Elsukov * but we need adjust icmp_cksum, because ICMPv6 cksum covers 911d8caf56eSAndrey V. Elsukov * IPv6 pseudo header and ICMPv6 types differs from ICMPv4. 912d8caf56eSAndrey V. Elsukov */ 913d8caf56eSAndrey V. Elsukov if (type == ICMP6_ECHO_REQUEST || type == ICMP6_ECHO_REPLY) { 914d8caf56eSAndrey V. Elsukov nat64_icmp_handle_echo(ip6, ICMP6(icmp), icmpid, type); 915d8caf56eSAndrey V. Elsukov return (m); 916d8caf56eSAndrey V. Elsukov } 917d8caf56eSAndrey V. Elsukov /* 918d8caf56eSAndrey V. Elsukov * For other types of ICMP messages we need to translate inner 919d8caf56eSAndrey V. Elsukov * IPv4 header to IPv6 header. 920d8caf56eSAndrey V. Elsukov * Assume ICMP src is the same as payload dst 921d8caf56eSAndrey V. Elsukov * E.g. we have ( GWsrc1 , NATIP1 ) in outer header 922d8caf56eSAndrey V. Elsukov * and ( NATIP1, Hostdst1 ) in ICMP copy header. 923d8caf56eSAndrey V. Elsukov * In that case, we already have map for NATIP1 and GWsrc1. 924d8caf56eSAndrey V. Elsukov * The only thing we need is to copy IPv6 map prefix to 925d8caf56eSAndrey V. Elsukov * Hostdst1. 926d8caf56eSAndrey V. Elsukov */ 927d8caf56eSAndrey V. Elsukov hlen = offset + ICMP_MINLEN; 928d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + sizeof(struct ip) + ICMP_MINLEN) { 929d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Message is too short %d", 930d8caf56eSAndrey V. Elsukov m->m_pkthdr.len); 931d8caf56eSAndrey V. Elsukov goto freeit; 932d8caf56eSAndrey V. Elsukov } 933d8caf56eSAndrey V. Elsukov m_copydata(m, hlen, sizeof(struct ip), (char *)&ip); 934d8caf56eSAndrey V. Elsukov if (ip.ip_v != IPVERSION) { 935d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Wrong IP version %d", ip.ip_v); 936d8caf56eSAndrey V. Elsukov goto freeit; 937d8caf56eSAndrey V. Elsukov } 938d8caf56eSAndrey V. Elsukov hlen += ip.ip_hl << 2; /* Skip inner IP header */ 939d8caf56eSAndrey V. Elsukov if (nat64_check_ip4(ip.ip_src.s_addr) != 0 || 940d8caf56eSAndrey V. Elsukov nat64_check_ip4(ip.ip_dst.s_addr) != 0 || 941782360deSAndrey V. Elsukov nat64_check_private_ip4(cfg, ip.ip_src.s_addr) != 0 || 942782360deSAndrey V. Elsukov nat64_check_private_ip4(cfg, ip.ip_dst.s_addr) != 0) { 943d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "IP addresses checks failed %04x -> %04x", 944d8caf56eSAndrey V. Elsukov ntohl(ip.ip_src.s_addr), ntohl(ip.ip_dst.s_addr)); 945d8caf56eSAndrey V. Elsukov goto freeit; 946d8caf56eSAndrey V. Elsukov } 947d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + ICMP_MINLEN) { 948d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Message is too short %d", 949d8caf56eSAndrey V. Elsukov m->m_pkthdr.len); 950d8caf56eSAndrey V. Elsukov goto freeit; 951d8caf56eSAndrey V. Elsukov } 952d8caf56eSAndrey V. Elsukov #if 0 953d8caf56eSAndrey V. Elsukov /* 954d8caf56eSAndrey V. Elsukov * Check that inner source matches the outer destination. 955d8caf56eSAndrey V. Elsukov * XXX: We need some method to convert IPv4 into IPv6 address here, 956d8caf56eSAndrey V. Elsukov * and compare IPv6 addresses. 957d8caf56eSAndrey V. Elsukov */ 958d8caf56eSAndrey V. Elsukov if (ip.ip_src.s_addr != nat64_get_ip4(&ip6->ip6_dst)) { 959d8caf56eSAndrey V. Elsukov DPRINTF(DP_GENERIC, "Inner source doesn't match destination ", 960d8caf56eSAndrey V. Elsukov "%04x vs %04x", ip.ip_src.s_addr, 961d8caf56eSAndrey V. Elsukov nat64_get_ip4(&ip6->ip6_dst)); 962d8caf56eSAndrey V. Elsukov goto freeit; 963d8caf56eSAndrey V. Elsukov } 964d8caf56eSAndrey V. Elsukov #endif 965d8caf56eSAndrey V. Elsukov /* 966d8caf56eSAndrey V. Elsukov * Create new mbuf for ICMPv6 datagram. 967d8caf56eSAndrey V. Elsukov * NOTE: len is data length just after inner IP header. 968d8caf56eSAndrey V. Elsukov */ 969d8caf56eSAndrey V. Elsukov len = m->m_pkthdr.len - hlen; 970d8caf56eSAndrey V. Elsukov if (sizeof(struct ip6_hdr) + 971d8caf56eSAndrey V. Elsukov sizeof(struct icmp6_hdr) + len > NAT64_ICMP6_PLEN) 972d8caf56eSAndrey V. Elsukov len = NAT64_ICMP6_PLEN - sizeof(struct icmp6_hdr) - 973d8caf56eSAndrey V. Elsukov sizeof(struct ip6_hdr); 974d8caf56eSAndrey V. Elsukov plen = sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr) + len; 975d8caf56eSAndrey V. Elsukov n = m_get2(offset + plen + max_hdr, M_NOWAIT, MT_HEADER, M_PKTHDR); 976d8caf56eSAndrey V. Elsukov if (n == NULL) { 977782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, nomem); 978d8caf56eSAndrey V. Elsukov m_freem(m); 979d8caf56eSAndrey V. Elsukov return (NULL); 980d8caf56eSAndrey V. Elsukov } 981d8caf56eSAndrey V. Elsukov m_move_pkthdr(n, m); 982d8caf56eSAndrey V. Elsukov M_ALIGN(n, offset + plen + max_hdr); 983d8caf56eSAndrey V. Elsukov n->m_len = n->m_pkthdr.len = offset + plen; 984d8caf56eSAndrey V. Elsukov /* Adjust ip6_plen in outer header */ 985d8caf56eSAndrey V. Elsukov ip6->ip6_plen = htons(plen); 986d8caf56eSAndrey V. Elsukov /* Construct new inner IPv6 header */ 987d8caf56eSAndrey V. Elsukov eip6 = mtodo(n, offset + sizeof(struct icmp6_hdr)); 988d8caf56eSAndrey V. Elsukov eip6->ip6_src = ip6->ip6_dst; 989d8caf56eSAndrey V. Elsukov /* Use the fact that we have single /96 prefix for IPv4 map */ 990d8caf56eSAndrey V. Elsukov eip6->ip6_dst = ip6->ip6_src; 991782360deSAndrey V. Elsukov nat64_embed_ip4(cfg, ip.ip_dst.s_addr, &eip6->ip6_dst); 992d8caf56eSAndrey V. Elsukov 993d8caf56eSAndrey V. Elsukov eip6->ip6_flow = htonl(ip.ip_tos << 20); 994d8caf56eSAndrey V. Elsukov eip6->ip6_vfc |= IPV6_VERSION; 995d8caf56eSAndrey V. Elsukov eip6->ip6_hlim = ip.ip_ttl; 996d8caf56eSAndrey V. Elsukov eip6->ip6_plen = htons(ntohs(ip.ip_len) - (ip.ip_hl << 2)); 997d8caf56eSAndrey V. Elsukov eip6->ip6_nxt = (ip.ip_p == IPPROTO_ICMP) ? IPPROTO_ICMPV6: ip.ip_p; 998d8caf56eSAndrey V. Elsukov m_copydata(m, hlen, len, (char *)(eip6 + 1)); 999d8caf56eSAndrey V. Elsukov /* 1000d8caf56eSAndrey V. Elsukov * We need to translate source port in the inner ULP header, 1001d8caf56eSAndrey V. Elsukov * and adjust ULP checksum. 1002d8caf56eSAndrey V. Elsukov */ 1003d8caf56eSAndrey V. Elsukov switch (ip.ip_p) { 1004d8caf56eSAndrey V. Elsukov case IPPROTO_TCP: 1005d8caf56eSAndrey V. Elsukov if (len < offsetof(struct tcphdr, th_sum)) 1006d8caf56eSAndrey V. Elsukov break; 1007d8caf56eSAndrey V. Elsukov tcp = TCP(eip6 + 1); 1008d8caf56eSAndrey V. Elsukov if (icmpid != 0) { 1009d8caf56eSAndrey V. Elsukov tcp->th_sum = cksum_adjust(tcp->th_sum, 1010d8caf56eSAndrey V. Elsukov tcp->th_sport, icmpid); 1011d8caf56eSAndrey V. Elsukov tcp->th_sport = icmpid; 1012d8caf56eSAndrey V. Elsukov } 1013d8caf56eSAndrey V. Elsukov tcp->th_sum = cksum_add(tcp->th_sum, 1014d8caf56eSAndrey V. Elsukov ~nat64_cksum_convert(eip6, &ip)); 1015d8caf56eSAndrey V. Elsukov break; 1016d8caf56eSAndrey V. Elsukov case IPPROTO_UDP: 1017d8caf56eSAndrey V. Elsukov if (len < offsetof(struct udphdr, uh_sum)) 1018d8caf56eSAndrey V. Elsukov break; 1019d8caf56eSAndrey V. Elsukov udp = UDP(eip6 + 1); 1020d8caf56eSAndrey V. Elsukov if (icmpid != 0) { 1021d8caf56eSAndrey V. Elsukov udp->uh_sum = cksum_adjust(udp->uh_sum, 1022d8caf56eSAndrey V. Elsukov udp->uh_sport, icmpid); 1023d8caf56eSAndrey V. Elsukov udp->uh_sport = icmpid; 1024d8caf56eSAndrey V. Elsukov } 1025d8caf56eSAndrey V. Elsukov udp->uh_sum = cksum_add(udp->uh_sum, 1026d8caf56eSAndrey V. Elsukov ~nat64_cksum_convert(eip6, &ip)); 1027d8caf56eSAndrey V. Elsukov break; 1028d8caf56eSAndrey V. Elsukov case IPPROTO_ICMP: 1029d8caf56eSAndrey V. Elsukov /* 1030d8caf56eSAndrey V. Elsukov * Check if this is an ICMP error message for echo request 1031d8caf56eSAndrey V. Elsukov * that we sent. I.e. ULP in the data containing invoking 1032d8caf56eSAndrey V. Elsukov * packet is IPPROTO_ICMP and its type is ICMP_ECHO. 1033d8caf56eSAndrey V. Elsukov */ 1034d8caf56eSAndrey V. Elsukov icmp = (struct icmp *)(eip6 + 1); 1035d8caf56eSAndrey V. Elsukov if (icmp->icmp_type != ICMP_ECHO) { 1036d8caf56eSAndrey V. Elsukov m_freem(n); 1037d8caf56eSAndrey V. Elsukov goto freeit; 1038d8caf56eSAndrey V. Elsukov } 1039d8caf56eSAndrey V. Elsukov /* 1040d8caf56eSAndrey V. Elsukov * For our client this original datagram should looks 1041d8caf56eSAndrey V. Elsukov * like it was ICMPv6 datagram with type ICMP6_ECHO_REQUEST. 1042d8caf56eSAndrey V. Elsukov * Thus we need adjust icmp_cksum and convert type from 1043d8caf56eSAndrey V. Elsukov * ICMP_ECHO to ICMP6_ECHO_REQUEST. 1044d8caf56eSAndrey V. Elsukov */ 1045d8caf56eSAndrey V. Elsukov nat64_icmp_handle_echo(eip6, ICMP6(icmp), icmpid, 1046d8caf56eSAndrey V. Elsukov ICMP6_ECHO_REQUEST); 1047d8caf56eSAndrey V. Elsukov } 1048d8caf56eSAndrey V. Elsukov m_freem(m); 1049d8caf56eSAndrey V. Elsukov /* Convert ICMPv4 into ICMPv6 header */ 1050d8caf56eSAndrey V. Elsukov icmp = mtodo(n, offset); 1051d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_type = type; 1052d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_code = code; 1053d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_mtu = htonl(mtu); 1054d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_cksum = 0; 1055d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_cksum = cksum_add( 1056d8caf56eSAndrey V. Elsukov ~in6_cksum_pseudo(ip6, plen, IPPROTO_ICMPV6, 0), 1057d8caf56eSAndrey V. Elsukov in_cksum_skip(n, n->m_pkthdr.len, offset)); 1058d8caf56eSAndrey V. Elsukov return (n); 1059d8caf56eSAndrey V. Elsukov freeit: 1060d8caf56eSAndrey V. Elsukov m_freem(m); 1061782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1062d8caf56eSAndrey V. Elsukov return (NULL); 1063d8caf56eSAndrey V. Elsukov } 1064d8caf56eSAndrey V. Elsukov 1065d8caf56eSAndrey V. Elsukov int 1066d8caf56eSAndrey V. Elsukov nat64_getlasthdr(struct mbuf *m, int *offset) 1067d8caf56eSAndrey V. Elsukov { 1068d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6; 1069d8caf56eSAndrey V. Elsukov struct ip6_hbh *hbh; 1070d8caf56eSAndrey V. Elsukov int proto, hlen; 1071d8caf56eSAndrey V. Elsukov 1072d8caf56eSAndrey V. Elsukov if (offset != NULL) 1073d8caf56eSAndrey V. Elsukov hlen = *offset; 1074d8caf56eSAndrey V. Elsukov else 1075d8caf56eSAndrey V. Elsukov hlen = 0; 1076d8caf56eSAndrey V. Elsukov 1077d8caf56eSAndrey V. Elsukov if (m->m_len < hlen + sizeof(*ip6)) 1078d8caf56eSAndrey V. Elsukov return (-1); 1079d8caf56eSAndrey V. Elsukov 1080d8caf56eSAndrey V. Elsukov ip6 = mtodo(m, hlen); 1081d8caf56eSAndrey V. Elsukov hlen += sizeof(*ip6); 1082d8caf56eSAndrey V. Elsukov proto = ip6->ip6_nxt; 1083d8caf56eSAndrey V. Elsukov /* Skip extension headers */ 1084d8caf56eSAndrey V. Elsukov while (proto == IPPROTO_HOPOPTS || proto == IPPROTO_ROUTING || 1085d8caf56eSAndrey V. Elsukov proto == IPPROTO_DSTOPTS) { 1086d8caf56eSAndrey V. Elsukov hbh = mtodo(m, hlen); 1087d8caf56eSAndrey V. Elsukov /* 1088d8caf56eSAndrey V. Elsukov * We expect mbuf has contigious data up to 1089d8caf56eSAndrey V. Elsukov * upper level header. 1090d8caf56eSAndrey V. Elsukov */ 1091d8caf56eSAndrey V. Elsukov if (m->m_len < hlen) 1092d8caf56eSAndrey V. Elsukov return (-1); 1093d8caf56eSAndrey V. Elsukov /* 1094d8caf56eSAndrey V. Elsukov * We doesn't support Jumbo payload option, 1095d8caf56eSAndrey V. Elsukov * so return error. 1096d8caf56eSAndrey V. Elsukov */ 1097d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_HOPOPTS && ip6->ip6_plen == 0) 1098d8caf56eSAndrey V. Elsukov return (-1); 1099d8caf56eSAndrey V. Elsukov proto = hbh->ip6h_nxt; 1100785c0d4dSAndrey V. Elsukov hlen += (hbh->ip6h_len + 1) << 3; 1101d8caf56eSAndrey V. Elsukov } 1102d8caf56eSAndrey V. Elsukov if (offset != NULL) 1103d8caf56eSAndrey V. Elsukov *offset = hlen; 1104d8caf56eSAndrey V. Elsukov return (proto); 1105d8caf56eSAndrey V. Elsukov } 1106d8caf56eSAndrey V. Elsukov 1107d8caf56eSAndrey V. Elsukov int 1108d8caf56eSAndrey V. Elsukov nat64_do_handle_ip4(struct mbuf *m, struct in6_addr *saddr, 1109782360deSAndrey V. Elsukov struct in6_addr *daddr, uint16_t lport, struct nat64_config *cfg, 1110d8caf56eSAndrey V. Elsukov void *logdata) 1111d8caf56eSAndrey V. Elsukov { 1112c570565fSAndrey V. Elsukov struct nhop6_basic nh; 1113d8caf56eSAndrey V. Elsukov struct ip6_hdr ip6; 1114c570565fSAndrey V. Elsukov struct sockaddr_in6 dst; 1115d8caf56eSAndrey V. Elsukov struct ip *ip; 1116d8caf56eSAndrey V. Elsukov struct mbufq mq; 1117d8caf56eSAndrey V. Elsukov uint16_t ip_id, ip_off; 1118d8caf56eSAndrey V. Elsukov uint16_t *csum; 1119d8caf56eSAndrey V. Elsukov int plen, hlen; 1120d8caf56eSAndrey V. Elsukov uint8_t proto; 1121d8caf56eSAndrey V. Elsukov 1122d8caf56eSAndrey V. Elsukov ip = mtod(m, struct ip*); 1123d8caf56eSAndrey V. Elsukov 1124d8caf56eSAndrey V. Elsukov if (ip->ip_ttl <= IPTTLDEC) { 1125d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_TIMXCEED, 1126782360deSAndrey V. Elsukov ICMP_TIMXCEED_INTRANS, 0, &cfg->stats, logdata); 1127d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1128d8caf56eSAndrey V. Elsukov } 1129d8caf56eSAndrey V. Elsukov 1130d8caf56eSAndrey V. Elsukov ip6.ip6_dst = *daddr; 1131d8caf56eSAndrey V. Elsukov ip6.ip6_src = *saddr; 1132d8caf56eSAndrey V. Elsukov 1133d8caf56eSAndrey V. Elsukov hlen = ip->ip_hl << 2; 1134d8caf56eSAndrey V. Elsukov plen = ntohs(ip->ip_len) - hlen; 1135d8caf56eSAndrey V. Elsukov proto = ip->ip_p; 1136d8caf56eSAndrey V. Elsukov 1137d8caf56eSAndrey V. Elsukov /* Save ip_id and ip_off, both are in network byte order */ 1138d8caf56eSAndrey V. Elsukov ip_id = ip->ip_id; 1139d8caf56eSAndrey V. Elsukov ip_off = ip->ip_off & htons(IP_OFFMASK | IP_MF); 1140d8caf56eSAndrey V. Elsukov 1141d8caf56eSAndrey V. Elsukov /* Fragment length must be multiple of 8 octets */ 1142d8caf56eSAndrey V. Elsukov if ((ip->ip_off & htons(IP_MF)) != 0 && (plen & 0x7) != 0) { 1143d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_PARAMPROB, 1144782360deSAndrey V. Elsukov ICMP_PARAMPROB_LENGTH, 0, &cfg->stats, logdata); 1145d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1146d8caf56eSAndrey V. Elsukov } 1147d8caf56eSAndrey V. Elsukov /* Fragmented ICMP is unsupported */ 1148d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_ICMP && ip_off != 0) { 1149d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to fragmented ICMP"); 1150782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1151d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1152d8caf56eSAndrey V. Elsukov } 1153d8caf56eSAndrey V. Elsukov 1154c570565fSAndrey V. Elsukov dst.sin6_addr = ip6.ip6_dst; 1155c570565fSAndrey V. Elsukov if (nat64_find_route6(&nh, &dst, m) != 0) { 1156782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, noroute6); 1157d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 1158782360deSAndrey V. Elsukov &cfg->stats, logdata); 1159d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1160d8caf56eSAndrey V. Elsukov } 1161c570565fSAndrey V. Elsukov if (nh.nh_mtu < plen + sizeof(ip6) && 1162c570565fSAndrey V. Elsukov (ip->ip_off & htons(IP_DF)) != 0) { 1163d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 1164782360deSAndrey V. Elsukov FRAGSZ(nh.nh_mtu) + sizeof(struct ip), &cfg->stats, logdata); 1165d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1166d8caf56eSAndrey V. Elsukov } 1167d8caf56eSAndrey V. Elsukov 1168d8caf56eSAndrey V. Elsukov ip6.ip6_flow = htonl(ip->ip_tos << 20); 1169d8caf56eSAndrey V. Elsukov ip6.ip6_vfc |= IPV6_VERSION; 1170d8caf56eSAndrey V. Elsukov #ifdef IPFIREWALL_NAT64_DIRECT_OUTPUT 1171d8caf56eSAndrey V. Elsukov ip6.ip6_hlim = ip->ip_ttl - IPTTLDEC; 1172d8caf56eSAndrey V. Elsukov #else 1173d8caf56eSAndrey V. Elsukov /* Forwarding code will decrement HLIM. */ 1174d8caf56eSAndrey V. Elsukov ip6.ip6_hlim = ip->ip_ttl; 1175d8caf56eSAndrey V. Elsukov #endif 1176d8caf56eSAndrey V. Elsukov ip6.ip6_plen = htons(plen); 1177d8caf56eSAndrey V. Elsukov ip6.ip6_nxt = (proto == IPPROTO_ICMP) ? IPPROTO_ICMPV6: proto; 1178d8caf56eSAndrey V. Elsukov /* Convert checksums. */ 1179d8caf56eSAndrey V. Elsukov switch (proto) { 1180d8caf56eSAndrey V. Elsukov case IPPROTO_TCP: 1181d8caf56eSAndrey V. Elsukov csum = &TCP(mtodo(m, hlen))->th_sum; 1182d8caf56eSAndrey V. Elsukov if (lport != 0) { 1183d8caf56eSAndrey V. Elsukov struct tcphdr *tcp = TCP(mtodo(m, hlen)); 1184d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, tcp->th_dport, lport); 1185d8caf56eSAndrey V. Elsukov tcp->th_dport = lport; 1186d8caf56eSAndrey V. Elsukov } 1187d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, ~nat64_cksum_convert(&ip6, ip)); 1188d8caf56eSAndrey V. Elsukov break; 1189d8caf56eSAndrey V. Elsukov case IPPROTO_UDP: 1190d8caf56eSAndrey V. Elsukov csum = &UDP(mtodo(m, hlen))->uh_sum; 1191d8caf56eSAndrey V. Elsukov if (lport != 0) { 1192d8caf56eSAndrey V. Elsukov struct udphdr *udp = UDP(mtodo(m, hlen)); 1193d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, udp->uh_dport, lport); 1194d8caf56eSAndrey V. Elsukov udp->uh_dport = lport; 1195d8caf56eSAndrey V. Elsukov } 1196d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, ~nat64_cksum_convert(&ip6, ip)); 1197d8caf56eSAndrey V. Elsukov break; 1198d8caf56eSAndrey V. Elsukov case IPPROTO_ICMP: 1199782360deSAndrey V. Elsukov m = nat64_icmp_translate(m, &ip6, lport, hlen, cfg); 1200c570565fSAndrey V. Elsukov if (m == NULL) /* stats already accounted */ 1201d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1202d8caf56eSAndrey V. Elsukov } 1203d8caf56eSAndrey V. Elsukov 1204d8caf56eSAndrey V. Elsukov m_adj(m, hlen); 1205d8caf56eSAndrey V. Elsukov mbufq_init(&mq, 255); 1206782360deSAndrey V. Elsukov nat64_fragment6(&cfg->stats, &ip6, &mq, m, nh.nh_mtu, ip_id, ip_off); 1207d8caf56eSAndrey V. Elsukov while ((m = mbufq_dequeue(&mq)) != NULL) { 1208c570565fSAndrey V. Elsukov if (nat64_output(nh.nh_ifp, m, (struct sockaddr *)&dst, 1209782360deSAndrey V. Elsukov &cfg->stats, logdata) != 0) 1210d8caf56eSAndrey V. Elsukov break; 1211782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, opcnt46); 1212d8caf56eSAndrey V. Elsukov } 1213d8caf56eSAndrey V. Elsukov mbufq_drain(&mq); 1214d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1215d8caf56eSAndrey V. Elsukov } 1216d8caf56eSAndrey V. Elsukov 1217d8caf56eSAndrey V. Elsukov int 1218d8caf56eSAndrey V. Elsukov nat64_handle_icmp6(struct mbuf *m, int hlen, uint32_t aaddr, uint16_t aport, 1219782360deSAndrey V. Elsukov struct nat64_config *cfg, void *logdata) 1220d8caf56eSAndrey V. Elsukov { 1221d8caf56eSAndrey V. Elsukov struct ip ip; 1222d8caf56eSAndrey V. Elsukov struct icmp6_hdr *icmp6; 1223d8caf56eSAndrey V. Elsukov struct ip6_frag *ip6f; 1224d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6, *ip6i; 1225d8caf56eSAndrey V. Elsukov uint32_t mtu; 1226d8caf56eSAndrey V. Elsukov int plen, proto; 1227d8caf56eSAndrey V. Elsukov uint8_t type, code; 1228d8caf56eSAndrey V. Elsukov 1229d8caf56eSAndrey V. Elsukov if (hlen == 0) { 1230d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 1231d8caf56eSAndrey V. Elsukov if (nat64_check_ip6(&ip6->ip6_src) != 0 || 1232d8caf56eSAndrey V. Elsukov nat64_check_ip6(&ip6->ip6_dst) != 0) 1233d8caf56eSAndrey V. Elsukov return (NAT64SKIP); 1234d8caf56eSAndrey V. Elsukov 1235d8caf56eSAndrey V. Elsukov proto = nat64_getlasthdr(m, &hlen); 1236d8caf56eSAndrey V. Elsukov if (proto != IPPROTO_ICMPV6) { 1237d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, 1238d8caf56eSAndrey V. Elsukov "dropped due to mbuf isn't contigious"); 1239782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1240d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1241d8caf56eSAndrey V. Elsukov } 1242d8caf56eSAndrey V. Elsukov } 1243d8caf56eSAndrey V. Elsukov 1244d8caf56eSAndrey V. Elsukov /* 1245d8caf56eSAndrey V. Elsukov * Translate ICMPv6 type and code to ICMPv4 (RFC7915). 1246d8caf56eSAndrey V. Elsukov * NOTE: ICMPv6 echo handled by nat64_do_handle_ip6(). 1247d8caf56eSAndrey V. Elsukov */ 1248d8caf56eSAndrey V. Elsukov icmp6 = mtodo(m, hlen); 1249d8caf56eSAndrey V. Elsukov mtu = 0; 1250d8caf56eSAndrey V. Elsukov switch (icmp6->icmp6_type) { 1251d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH: 1252d8caf56eSAndrey V. Elsukov type = ICMP_UNREACH; 1253d8caf56eSAndrey V. Elsukov switch (icmp6->icmp6_code) { 1254d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_NOROUTE: 1255d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_BEYONDSCOPE: 1256d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_ADDR: 1257d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_HOST; 1258d8caf56eSAndrey V. Elsukov break; 1259d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_ADMIN: 1260d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_HOST_PROHIB; 1261d8caf56eSAndrey V. Elsukov break; 1262d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_NOPORT: 1263d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_PORT; 1264d8caf56eSAndrey V. Elsukov break; 1265d8caf56eSAndrey V. Elsukov default: 1266d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d," 1267d8caf56eSAndrey V. Elsukov " code %d", icmp6->icmp6_type, 1268d8caf56eSAndrey V. Elsukov icmp6->icmp6_code); 1269782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1270d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1271d8caf56eSAndrey V. Elsukov } 1272d8caf56eSAndrey V. Elsukov break; 1273d8caf56eSAndrey V. Elsukov case ICMP6_PACKET_TOO_BIG: 1274d8caf56eSAndrey V. Elsukov type = ICMP_UNREACH; 1275d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_NEEDFRAG; 1276d8caf56eSAndrey V. Elsukov mtu = ntohl(icmp6->icmp6_mtu); 1277d8caf56eSAndrey V. Elsukov if (mtu < IPV6_MMTU) { 1278d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Wrong MTU %d in ICMPv6 type %d," 1279d8caf56eSAndrey V. Elsukov " code %d", mtu, icmp6->icmp6_type, 1280d8caf56eSAndrey V. Elsukov icmp6->icmp6_code); 1281782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1282d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1283d8caf56eSAndrey V. Elsukov } 1284d8caf56eSAndrey V. Elsukov /* 1285d8caf56eSAndrey V. Elsukov * Adjust MTU to reflect difference between 1286d8caf56eSAndrey V. Elsukov * IPv6 an IPv4 headers. 1287d8caf56eSAndrey V. Elsukov */ 1288d8caf56eSAndrey V. Elsukov mtu -= sizeof(struct ip6_hdr) - sizeof(struct ip); 1289d8caf56eSAndrey V. Elsukov break; 1290c5f2dbb6SAndrey V. Elsukov case ICMP6_TIME_EXCEEDED: 1291d8caf56eSAndrey V. Elsukov type = ICMP_TIMXCEED; 1292c5f2dbb6SAndrey V. Elsukov code = icmp6->icmp6_code; 1293d8caf56eSAndrey V. Elsukov break; 1294d8caf56eSAndrey V. Elsukov case ICMP6_PARAM_PROB: 1295d8caf56eSAndrey V. Elsukov switch (icmp6->icmp6_code) { 1296d8caf56eSAndrey V. Elsukov case ICMP6_PARAMPROB_HEADER: 1297d8caf56eSAndrey V. Elsukov type = ICMP_PARAMPROB; 1298d8caf56eSAndrey V. Elsukov code = ICMP_PARAMPROB_ERRATPTR; 1299d8caf56eSAndrey V. Elsukov mtu = ntohl(icmp6->icmp6_pptr); 1300d8caf56eSAndrey V. Elsukov switch (mtu) { 1301d8caf56eSAndrey V. Elsukov case 0: /* Version/Traffic Class */ 1302d8caf56eSAndrey V. Elsukov case 1: /* Traffic Class/Flow Label */ 1303d8caf56eSAndrey V. Elsukov break; 1304d8caf56eSAndrey V. Elsukov case 4: /* Payload Length */ 1305d8caf56eSAndrey V. Elsukov case 5: 1306d8caf56eSAndrey V. Elsukov mtu = 2; 1307d8caf56eSAndrey V. Elsukov break; 1308d8caf56eSAndrey V. Elsukov case 6: /* Next Header */ 1309d8caf56eSAndrey V. Elsukov mtu = 9; 1310d8caf56eSAndrey V. Elsukov break; 1311d8caf56eSAndrey V. Elsukov case 7: /* Hop Limit */ 1312d8caf56eSAndrey V. Elsukov mtu = 8; 1313d8caf56eSAndrey V. Elsukov break; 1314d8caf56eSAndrey V. Elsukov default: 1315d8caf56eSAndrey V. Elsukov if (mtu >= 8 && mtu <= 23) { 1316d8caf56eSAndrey V. Elsukov mtu = 12; /* Source address */ 1317d8caf56eSAndrey V. Elsukov break; 1318d8caf56eSAndrey V. Elsukov } 1319d8caf56eSAndrey V. Elsukov if (mtu >= 24 && mtu <= 39) { 1320d8caf56eSAndrey V. Elsukov mtu = 16; /* Destination address */ 1321d8caf56eSAndrey V. Elsukov break; 1322d8caf56eSAndrey V. Elsukov } 1323d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d," 1324d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp6->icmp6_type, 1325d8caf56eSAndrey V. Elsukov icmp6->icmp6_code, mtu); 1326782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1327d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1328d8caf56eSAndrey V. Elsukov } 1329d8caf56eSAndrey V. Elsukov case ICMP6_PARAMPROB_NEXTHEADER: 1330d8caf56eSAndrey V. Elsukov type = ICMP_UNREACH; 1331d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_PROTOCOL; 1332d8caf56eSAndrey V. Elsukov break; 1333d8caf56eSAndrey V. Elsukov default: 1334d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d," 1335d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp6->icmp6_type, 1336d8caf56eSAndrey V. Elsukov icmp6->icmp6_code, ntohl(icmp6->icmp6_pptr)); 1337782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1338d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1339d8caf56eSAndrey V. Elsukov } 1340d8caf56eSAndrey V. Elsukov break; 1341d8caf56eSAndrey V. Elsukov default: 1342d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d, code %d", 1343d8caf56eSAndrey V. Elsukov icmp6->icmp6_type, icmp6->icmp6_code); 1344782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1345d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1346d8caf56eSAndrey V. Elsukov } 1347d8caf56eSAndrey V. Elsukov 1348d8caf56eSAndrey V. Elsukov hlen += sizeof(struct icmp6_hdr); 1349d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + sizeof(struct ip6_hdr) + ICMP_MINLEN) { 1350782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1351d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Message is too short %d", 1352d8caf56eSAndrey V. Elsukov m->m_pkthdr.len); 1353d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1354d8caf56eSAndrey V. Elsukov } 1355d8caf56eSAndrey V. Elsukov /* 1356d8caf56eSAndrey V. Elsukov * We need at least ICMP_MINLEN bytes of original datagram payload 1357d8caf56eSAndrey V. Elsukov * to generate ICMP message. It is nice that ICMP_MINLEN is equal 1358d8caf56eSAndrey V. Elsukov * to sizeof(struct ip6_frag). So, if embedded datagram had a fragment 1359d8caf56eSAndrey V. Elsukov * header we will not have to do m_pullup() again. 1360d8caf56eSAndrey V. Elsukov * 1361d8caf56eSAndrey V. Elsukov * What we have here: 1362d8caf56eSAndrey V. Elsukov * Outer header: (IPv6iGW, v4mapPRefix+v4exthost) 1363d8caf56eSAndrey V. Elsukov * Inner header: (v4mapPRefix+v4host, IPv6iHost) [sport, dport] 1364d8caf56eSAndrey V. Elsukov * We need to translate it to: 1365d8caf56eSAndrey V. Elsukov * 1366d8caf56eSAndrey V. Elsukov * Outer header: (alias_host, v4exthost) 1367d8caf56eSAndrey V. Elsukov * Inner header: (v4exthost, alias_host) [sport, alias_port] 1368d8caf56eSAndrey V. Elsukov * 1369d8caf56eSAndrey V. Elsukov * Assume caller function has checked if v4mapPRefix+v4host 1370d8caf56eSAndrey V. Elsukov * matches configured prefix. 1371d8caf56eSAndrey V. Elsukov * The only two things we should be provided with are mapping between 1372d8caf56eSAndrey V. Elsukov * IPv6iHost <> alias_host and between dport and alias_port. 1373d8caf56eSAndrey V. Elsukov */ 1374d8caf56eSAndrey V. Elsukov if (m->m_len < hlen + sizeof(struct ip6_hdr) + ICMP_MINLEN) 1375d8caf56eSAndrey V. Elsukov m = m_pullup(m, hlen + sizeof(struct ip6_hdr) + ICMP_MINLEN); 1376d8caf56eSAndrey V. Elsukov if (m == NULL) { 1377782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, nomem); 1378d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1379d8caf56eSAndrey V. Elsukov } 1380d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 1381d8caf56eSAndrey V. Elsukov ip6i = mtodo(m, hlen); 1382d8caf56eSAndrey V. Elsukov ip6f = NULL; 1383d8caf56eSAndrey V. Elsukov proto = ip6i->ip6_nxt; 1384d8caf56eSAndrey V. Elsukov plen = ntohs(ip6i->ip6_plen); 1385d8caf56eSAndrey V. Elsukov hlen += sizeof(struct ip6_hdr); 1386d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_FRAGMENT) { 1387d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + sizeof(struct ip6_frag) + 1388d8caf56eSAndrey V. Elsukov ICMP_MINLEN) 1389d8caf56eSAndrey V. Elsukov goto fail; 1390d8caf56eSAndrey V. Elsukov ip6f = mtodo(m, hlen); 1391d8caf56eSAndrey V. Elsukov proto = ip6f->ip6f_nxt; 1392d8caf56eSAndrey V. Elsukov plen -= sizeof(struct ip6_frag); 1393d8caf56eSAndrey V. Elsukov hlen += sizeof(struct ip6_frag); 1394d8caf56eSAndrey V. Elsukov /* Ajust MTU to reflect frag header size */ 1395d8caf56eSAndrey V. Elsukov if (type == ICMP_UNREACH && code == ICMP_UNREACH_NEEDFRAG) 1396d8caf56eSAndrey V. Elsukov mtu -= sizeof(struct ip6_frag); 1397d8caf56eSAndrey V. Elsukov } 1398d8caf56eSAndrey V. Elsukov if (proto != IPPROTO_TCP && proto != IPPROTO_UDP) { 1399d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported proto %d in the inner header", 1400d8caf56eSAndrey V. Elsukov proto); 1401d8caf56eSAndrey V. Elsukov goto fail; 1402d8caf56eSAndrey V. Elsukov } 1403d8caf56eSAndrey V. Elsukov if (nat64_check_ip6(&ip6i->ip6_src) != 0 || 1404d8caf56eSAndrey V. Elsukov nat64_check_ip6(&ip6i->ip6_dst) != 0) { 1405d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Inner addresses do not passes the check"); 1406d8caf56eSAndrey V. Elsukov goto fail; 1407d8caf56eSAndrey V. Elsukov } 1408d8caf56eSAndrey V. Elsukov /* Check if outer dst is the same as inner src */ 1409d8caf56eSAndrey V. Elsukov if (!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &ip6i->ip6_src)) { 1410d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Inner src doesn't match outer dst"); 1411d8caf56eSAndrey V. Elsukov goto fail; 1412d8caf56eSAndrey V. Elsukov } 1413d8caf56eSAndrey V. Elsukov 1414d8caf56eSAndrey V. Elsukov /* Now we need to make a fake IPv4 packet to generate ICMP message */ 1415d8caf56eSAndrey V. Elsukov ip.ip_dst.s_addr = aaddr; 1416782360deSAndrey V. Elsukov ip.ip_src.s_addr = nat64_extract_ip4(cfg, &ip6i->ip6_src); 1417d8caf56eSAndrey V. Elsukov /* XXX: Make fake ulp header */ 1418d8caf56eSAndrey V. Elsukov #ifdef IPFIREWALL_NAT64_DIRECT_OUTPUT 1419d8caf56eSAndrey V. Elsukov ip6i->ip6_hlim += IPV6_HLIMDEC; /* init_ip4hdr will decrement it */ 1420d8caf56eSAndrey V. Elsukov #endif 1421d8caf56eSAndrey V. Elsukov nat64_init_ip4hdr(ip6i, ip6f, plen, proto, &ip); 1422d8caf56eSAndrey V. Elsukov m_adj(m, hlen - sizeof(struct ip)); 1423d8caf56eSAndrey V. Elsukov bcopy(&ip, mtod(m, void *), sizeof(ip)); 1424782360deSAndrey V. Elsukov nat64_icmp_reflect(m, type, code, (uint16_t)mtu, &cfg->stats, 1425782360deSAndrey V. Elsukov logdata); 1426d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1427d8caf56eSAndrey V. Elsukov fail: 1428d8caf56eSAndrey V. Elsukov /* 1429d8caf56eSAndrey V. Elsukov * We must call m_freem() because mbuf pointer could be 1430d8caf56eSAndrey V. Elsukov * changed with m_pullup(). 1431d8caf56eSAndrey V. Elsukov */ 1432d8caf56eSAndrey V. Elsukov m_freem(m); 1433782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1434d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1435d8caf56eSAndrey V. Elsukov } 1436d8caf56eSAndrey V. Elsukov 1437d8caf56eSAndrey V. Elsukov int 1438d8caf56eSAndrey V. Elsukov nat64_do_handle_ip6(struct mbuf *m, uint32_t aaddr, uint16_t aport, 1439782360deSAndrey V. Elsukov struct nat64_config *cfg, void *logdata) 1440d8caf56eSAndrey V. Elsukov { 1441d8caf56eSAndrey V. Elsukov struct ip ip; 1442c570565fSAndrey V. Elsukov struct nhop4_basic nh; 1443c570565fSAndrey V. Elsukov struct sockaddr_in dst; 1444d8caf56eSAndrey V. Elsukov struct ip6_frag *frag; 1445d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6; 1446d8caf56eSAndrey V. Elsukov struct icmp6_hdr *icmp6; 1447d8caf56eSAndrey V. Elsukov uint16_t *csum; 1448db68f783SBjoern A. Zeeb int plen, hlen, proto; 1449d8caf56eSAndrey V. Elsukov 1450d8caf56eSAndrey V. Elsukov /* 1451d8caf56eSAndrey V. Elsukov * XXX: we expect ipfw_chk() did m_pullup() up to upper level 1452d8caf56eSAndrey V. Elsukov * protocol's headers. Also we skip some checks, that ip6_input(), 1453d8caf56eSAndrey V. Elsukov * ip6_forward(), ip6_fastfwd() and ipfw_chk() already did. 1454d8caf56eSAndrey V. Elsukov */ 1455d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 1456d8caf56eSAndrey V. Elsukov if (nat64_check_ip6(&ip6->ip6_src) != 0 || 1457d8caf56eSAndrey V. Elsukov nat64_check_ip6(&ip6->ip6_dst) != 0) { 1458d8caf56eSAndrey V. Elsukov return (NAT64SKIP); 1459d8caf56eSAndrey V. Elsukov } 1460d8caf56eSAndrey V. Elsukov 1461d8caf56eSAndrey V. Elsukov /* Starting from this point we must not return zero */ 1462d8caf56eSAndrey V. Elsukov ip.ip_src.s_addr = aaddr; 1463d8caf56eSAndrey V. Elsukov if (nat64_check_ip4(ip.ip_src.s_addr) != 0) { 1464782360deSAndrey V. Elsukov DPRINTF(DP_GENERIC | DP_DROPS, "invalid source address: %08x", 1465d8caf56eSAndrey V. Elsukov ip.ip_src.s_addr); 1466782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1467d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1468d8caf56eSAndrey V. Elsukov } 1469d8caf56eSAndrey V. Elsukov 1470782360deSAndrey V. Elsukov ip.ip_dst.s_addr = nat64_extract_ip4(cfg, &ip6->ip6_dst); 1471d8caf56eSAndrey V. Elsukov if (ip.ip_dst.s_addr == 0) { 1472782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1473d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1474d8caf56eSAndrey V. Elsukov } 1475d8caf56eSAndrey V. Elsukov 1476d8caf56eSAndrey V. Elsukov if (ip6->ip6_hlim <= IPV6_HLIMDEC) { 1477d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_TIME_EXCEEDED, 1478782360deSAndrey V. Elsukov ICMP6_TIME_EXCEED_TRANSIT, 0, &cfg->stats, logdata); 1479d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1480d8caf56eSAndrey V. Elsukov } 1481d8caf56eSAndrey V. Elsukov 1482d8caf56eSAndrey V. Elsukov hlen = 0; 1483d8caf56eSAndrey V. Elsukov plen = ntohs(ip6->ip6_plen); 1484d8caf56eSAndrey V. Elsukov proto = nat64_getlasthdr(m, &hlen); 1485d8caf56eSAndrey V. Elsukov if (proto < 0) { 1486d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to mbuf isn't contigious"); 1487782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1488d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1489d8caf56eSAndrey V. Elsukov } 1490d8caf56eSAndrey V. Elsukov frag = NULL; 1491d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_FRAGMENT) { 1492d8caf56eSAndrey V. Elsukov /* ipfw_chk should m_pullup up to frag header */ 1493d8caf56eSAndrey V. Elsukov if (m->m_len < hlen + sizeof(*frag)) { 1494d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, 1495d8caf56eSAndrey V. Elsukov "dropped due to mbuf isn't contigious"); 1496782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1497d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1498d8caf56eSAndrey V. Elsukov } 1499d8caf56eSAndrey V. Elsukov frag = mtodo(m, hlen); 1500d8caf56eSAndrey V. Elsukov proto = frag->ip6f_nxt; 1501d8caf56eSAndrey V. Elsukov hlen += sizeof(*frag); 1502d8caf56eSAndrey V. Elsukov /* Fragmented ICMPv6 is unsupported */ 1503d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_ICMPV6) { 1504d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to fragmented ICMPv6"); 1505782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1506d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1507d8caf56eSAndrey V. Elsukov } 1508d8caf56eSAndrey V. Elsukov /* Fragment length must be multiple of 8 octets */ 1509d8caf56eSAndrey V. Elsukov if ((frag->ip6f_offlg & IP6F_MORE_FRAG) != 0 && 1510d8caf56eSAndrey V. Elsukov ((plen + sizeof(struct ip6_hdr) - hlen) & 0x7) != 0) { 1511d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_PARAM_PROB, 1512d8caf56eSAndrey V. Elsukov ICMP6_PARAMPROB_HEADER, 1513782360deSAndrey V. Elsukov offsetof(struct ip6_hdr, ip6_plen), &cfg->stats, 1514d8caf56eSAndrey V. Elsukov logdata); 1515d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1516d8caf56eSAndrey V. Elsukov } 1517d8caf56eSAndrey V. Elsukov } 1518d8caf56eSAndrey V. Elsukov plen -= hlen - sizeof(struct ip6_hdr); 1519d8caf56eSAndrey V. Elsukov if (plen < 0 || m->m_pkthdr.len < plen + hlen) { 1520d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "plen %d, pkthdr.len %d, hlen %d", 1521d8caf56eSAndrey V. Elsukov plen, m->m_pkthdr.len, hlen); 1522782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, dropped); 1523d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1524d8caf56eSAndrey V. Elsukov } 1525d8caf56eSAndrey V. Elsukov 1526d8caf56eSAndrey V. Elsukov icmp6 = NULL; /* Make gcc happy */ 1527d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_ICMPV6) { 1528d8caf56eSAndrey V. Elsukov icmp6 = mtodo(m, hlen); 1529d8caf56eSAndrey V. Elsukov if (icmp6->icmp6_type != ICMP6_ECHO_REQUEST && 1530d8caf56eSAndrey V. Elsukov icmp6->icmp6_type != ICMP6_ECHO_REPLY) 1531d8caf56eSAndrey V. Elsukov return (nat64_handle_icmp6(m, hlen, aaddr, aport, 1532782360deSAndrey V. Elsukov cfg, logdata)); 1533d8caf56eSAndrey V. Elsukov } 1534c570565fSAndrey V. Elsukov dst.sin_addr.s_addr = ip.ip_dst.s_addr; 1535c570565fSAndrey V. Elsukov if (nat64_find_route4(&nh, &dst, m) != 0) { 1536782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, noroute4); 1537d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_DST_UNREACH, 1538782360deSAndrey V. Elsukov ICMP6_DST_UNREACH_NOROUTE, 0, &cfg->stats, logdata); 1539d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1540d8caf56eSAndrey V. Elsukov } 1541c570565fSAndrey V. Elsukov if (nh.nh_mtu < plen + sizeof(ip)) { 1542c570565fSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_PACKET_TOO_BIG, 0, nh.nh_mtu, 1543782360deSAndrey V. Elsukov &cfg->stats, logdata); 1544d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1545d8caf56eSAndrey V. Elsukov } 1546d8caf56eSAndrey V. Elsukov nat64_init_ip4hdr(ip6, frag, plen, proto, &ip); 1547d8caf56eSAndrey V. Elsukov /* Convert checksums. */ 1548d8caf56eSAndrey V. Elsukov switch (proto) { 1549d8caf56eSAndrey V. Elsukov case IPPROTO_TCP: 1550d8caf56eSAndrey V. Elsukov csum = &TCP(mtodo(m, hlen))->th_sum; 1551d8caf56eSAndrey V. Elsukov if (aport != 0) { 1552d8caf56eSAndrey V. Elsukov struct tcphdr *tcp = TCP(mtodo(m, hlen)); 1553d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, tcp->th_sport, aport); 1554d8caf56eSAndrey V. Elsukov tcp->th_sport = aport; 1555d8caf56eSAndrey V. Elsukov } 1556d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, nat64_cksum_convert(ip6, &ip)); 1557d8caf56eSAndrey V. Elsukov break; 1558d8caf56eSAndrey V. Elsukov case IPPROTO_UDP: 1559d8caf56eSAndrey V. Elsukov csum = &UDP(mtodo(m, hlen))->uh_sum; 1560d8caf56eSAndrey V. Elsukov if (aport != 0) { 1561d8caf56eSAndrey V. Elsukov struct udphdr *udp = UDP(mtodo(m, hlen)); 1562d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, udp->uh_sport, aport); 1563d8caf56eSAndrey V. Elsukov udp->uh_sport = aport; 1564d8caf56eSAndrey V. Elsukov } 1565d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, nat64_cksum_convert(ip6, &ip)); 1566d8caf56eSAndrey V. Elsukov break; 1567d8caf56eSAndrey V. Elsukov case IPPROTO_ICMPV6: 1568d8caf56eSAndrey V. Elsukov /* Checksum in ICMPv6 covers pseudo header */ 1569d8caf56eSAndrey V. Elsukov csum = &icmp6->icmp6_cksum; 1570d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, in6_cksum_pseudo(ip6, plen, 1571d8caf56eSAndrey V. Elsukov IPPROTO_ICMPV6, 0)); 1572d8caf56eSAndrey V. Elsukov /* Convert ICMPv6 types to ICMP */ 1573c570565fSAndrey V. Elsukov proto = *(uint16_t *)icmp6; /* save old word for cksum_adjust */ 1574d8caf56eSAndrey V. Elsukov if (icmp6->icmp6_type == ICMP6_ECHO_REQUEST) 1575d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = ICMP_ECHO; 1576d8caf56eSAndrey V. Elsukov else /* ICMP6_ECHO_REPLY */ 1577d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = ICMP_ECHOREPLY; 1578c570565fSAndrey V. Elsukov *csum = cksum_adjust(*csum, (uint16_t)proto, 1579c570565fSAndrey V. Elsukov *(uint16_t *)icmp6); 1580d8caf56eSAndrey V. Elsukov if (aport != 0) { 1581d8caf56eSAndrey V. Elsukov uint16_t old_id = icmp6->icmp6_id; 1582d8caf56eSAndrey V. Elsukov icmp6->icmp6_id = aport; 1583d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, old_id, aport); 1584d8caf56eSAndrey V. Elsukov } 1585d8caf56eSAndrey V. Elsukov break; 1586d8caf56eSAndrey V. Elsukov }; 1587d8caf56eSAndrey V. Elsukov 1588d8caf56eSAndrey V. Elsukov m_adj(m, hlen - sizeof(ip)); 1589d8caf56eSAndrey V. Elsukov bcopy(&ip, mtod(m, void *), sizeof(ip)); 1590782360deSAndrey V. Elsukov if (nat64_output(nh.nh_ifp, m, (struct sockaddr *)&dst, 1591782360deSAndrey V. Elsukov &cfg->stats, logdata) == 0) 1592782360deSAndrey V. Elsukov NAT64STAT_INC(&cfg->stats, opcnt64); 1593d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1594d8caf56eSAndrey V. Elsukov } 1595d8caf56eSAndrey V. Elsukov 1596