1d8caf56eSAndrey V. Elsukov /*- 2d8caf56eSAndrey V. Elsukov * Copyright (c) 2015-2016 Yandex LLC 3d8caf56eSAndrey V. Elsukov * Copyright (c) 2015-2016 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 <netpfil/ipfw/nat64/ip_fw_nat64.h> 70d8caf56eSAndrey V. Elsukov #include <netpfil/ipfw/nat64/nat64_translate.h> 71d8caf56eSAndrey V. Elsukov #include <machine/in_cksum.h> 72d8caf56eSAndrey V. Elsukov 73d8caf56eSAndrey V. Elsukov static void 74d8caf56eSAndrey V. Elsukov nat64_log(struct pfloghdr *logdata, struct mbuf *m, sa_family_t family) 75d8caf56eSAndrey V. Elsukov { 76d8caf56eSAndrey V. Elsukov 77d8caf56eSAndrey V. Elsukov logdata->dir = PF_OUT; 78d8caf56eSAndrey V. Elsukov logdata->af = family; 79d8caf56eSAndrey V. Elsukov ipfw_bpf_mtap2(logdata, PFLOG_HDRLEN, m); 80d8caf56eSAndrey V. Elsukov } 81c570565fSAndrey V. Elsukov 82d8caf56eSAndrey V. Elsukov #ifdef IPFIREWALL_NAT64_DIRECT_OUTPUT 83c570565fSAndrey V. Elsukov static NAT64NOINLINE int nat64_find_route4(struct nhop4_basic *, 84c570565fSAndrey V. Elsukov struct sockaddr_in *, struct mbuf *); 85c570565fSAndrey V. Elsukov static NAT64NOINLINE int nat64_find_route6(struct nhop6_basic *, 86c570565fSAndrey V. Elsukov struct sockaddr_in6 *, struct mbuf *); 87d8caf56eSAndrey V. Elsukov 88c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 89d8caf56eSAndrey V. Elsukov nat64_output(struct ifnet *ifp, struct mbuf *m, 90d8caf56eSAndrey V. Elsukov struct sockaddr *dst, struct route *ro, nat64_stats_block *stats, 91d8caf56eSAndrey V. Elsukov 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); 97d8caf56eSAndrey V. Elsukov error = (*ifp->if_output)(ifp, m, dst, ro); 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 104d8caf56eSAndrey V. Elsukov nat64_output_one(struct mbuf *m, nat64_stats_block *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 158d8caf56eSAndrey V. Elsukov nat64_output(struct ifnet *ifp, struct mbuf *m, 159d8caf56eSAndrey V. Elsukov struct sockaddr *dst, struct route *ro, nat64_stats_block *stats, 160d8caf56eSAndrey V. Elsukov void *logdata) 161d8caf56eSAndrey V. Elsukov { 162d8caf56eSAndrey V. Elsukov struct ip *ip4; 163d8caf56eSAndrey V. Elsukov int ret, af; 164d8caf56eSAndrey V. Elsukov 165d8caf56eSAndrey V. Elsukov ip4 = mtod(m, struct ip *); 166d8caf56eSAndrey V. Elsukov switch (ip4->ip_v) { 167d8caf56eSAndrey V. Elsukov case IPVERSION: 168d8caf56eSAndrey V. Elsukov af = AF_INET; 169d8caf56eSAndrey V. Elsukov ret = NETISR_IP; 170d8caf56eSAndrey V. Elsukov break; 171d8caf56eSAndrey V. Elsukov case (IPV6_VERSION >> 4): 172d8caf56eSAndrey V. Elsukov af = AF_INET6; 173d8caf56eSAndrey V. Elsukov ret = NETISR_IPV6; 174d8caf56eSAndrey V. Elsukov break; 175d8caf56eSAndrey V. Elsukov default: 176d8caf56eSAndrey V. Elsukov m_freem(m); 177d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 178d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "unknown IP version"); 179d8caf56eSAndrey V. Elsukov return (EAFNOSUPPORT); 180d8caf56eSAndrey V. Elsukov } 181d8caf56eSAndrey V. Elsukov if (logdata != NULL) 182d8caf56eSAndrey V. Elsukov nat64_log(logdata, m, af); 183d8caf56eSAndrey V. Elsukov ret = netisr_queue(ret, m); 184d8caf56eSAndrey V. Elsukov if (ret != 0) 185d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, oerrors); 186d8caf56eSAndrey V. Elsukov return (ret); 187d8caf56eSAndrey V. Elsukov } 188d8caf56eSAndrey V. Elsukov 189c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 190d8caf56eSAndrey V. Elsukov nat64_output_one(struct mbuf *m, nat64_stats_block *stats, void *logdata) 191d8caf56eSAndrey V. Elsukov { 192d8caf56eSAndrey V. Elsukov 193d8caf56eSAndrey V. Elsukov return (nat64_output(NULL, m, NULL, NULL, stats, logdata)); 194d8caf56eSAndrey V. Elsukov } 195d8caf56eSAndrey V. Elsukov #endif /* !IPFIREWALL_NAT64_DIRECT_OUTPUT */ 196d8caf56eSAndrey V. Elsukov 197d8caf56eSAndrey V. Elsukov 198d8caf56eSAndrey V. Elsukov #if 0 199d8caf56eSAndrey V. Elsukov void print_ipv6_header(struct ip6_hdr *ip6, char *buf, size_t bufsize); 200d8caf56eSAndrey V. Elsukov 201d8caf56eSAndrey V. Elsukov void 202d8caf56eSAndrey V. Elsukov print_ipv6_header(struct ip6_hdr *ip6, char *buf, size_t bufsize) 203d8caf56eSAndrey V. Elsukov { 204d8caf56eSAndrey V. Elsukov char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN]; 205d8caf56eSAndrey V. Elsukov 206d8caf56eSAndrey V. Elsukov inet_ntop(AF_INET6, &ip6->ip6_src, sbuf, sizeof(sbuf)); 207d8caf56eSAndrey V. Elsukov inet_ntop(AF_INET6, &ip6->ip6_dst, dbuf, sizeof(dbuf)); 208d8caf56eSAndrey V. Elsukov snprintf(buf, bufsize, "%s -> %s %d", sbuf, dbuf, ip6->ip6_nxt); 209d8caf56eSAndrey V. Elsukov } 210d8caf56eSAndrey V. Elsukov 211d8caf56eSAndrey V. Elsukov 212c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 213d8caf56eSAndrey V. Elsukov nat64_embed_ip4(struct nat64_cfg *cfg, in_addr_t ia, struct in6_addr *ip6) 214d8caf56eSAndrey V. Elsukov { 215d8caf56eSAndrey V. Elsukov 216d8caf56eSAndrey V. Elsukov /* assume the prefix is properly filled with zeros */ 217d8caf56eSAndrey V. Elsukov bcopy(&cfg->prefix, ip6, sizeof(*ip6)); 218d8caf56eSAndrey V. Elsukov switch (cfg->plen) { 219d8caf56eSAndrey V. Elsukov case 32: 220d8caf56eSAndrey V. Elsukov case 96: 221d8caf56eSAndrey V. Elsukov ip6->s6_addr32[cfg->plen / 32] = ia; 222d8caf56eSAndrey V. Elsukov break; 223d8caf56eSAndrey V. Elsukov case 40: 224d8caf56eSAndrey V. Elsukov case 48: 225d8caf56eSAndrey V. Elsukov case 56: 226d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 227d8caf56eSAndrey V. Elsukov ip6->s6_addr32[1] = cfg->prefix.s6_addr32[1] | 228d8caf56eSAndrey V. Elsukov (ia >> (cfg->plen % 32)); 229d8caf56eSAndrey V. Elsukov ip6->s6_addr32[2] = ia << (24 - cfg->plen % 32); 230d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 231d8caf56eSAndrey V. Elsukov ip6->s6_addr32[1] = cfg->prefix.s6_addr32[1] | 232d8caf56eSAndrey V. Elsukov (ia << (cfg->plen % 32)); 233d8caf56eSAndrey V. Elsukov ip6->s6_addr32[2] = ia >> (24 - cfg->plen % 32); 234d8caf56eSAndrey V. Elsukov #endif 235d8caf56eSAndrey V. Elsukov break; 236d8caf56eSAndrey V. Elsukov case 64: 237d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 238d8caf56eSAndrey V. Elsukov ip6->s6_addr32[2] = ia >> 8; 239d8caf56eSAndrey V. Elsukov ip6->s6_addr32[3] = ia << 24; 240d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 241d8caf56eSAndrey V. Elsukov ip6->s6_addr32[2] = ia << 8; 242d8caf56eSAndrey V. Elsukov ip6->s6_addr32[3] = ia >> 24; 243d8caf56eSAndrey V. Elsukov #endif 244d8caf56eSAndrey V. Elsukov break; 245d8caf56eSAndrey V. Elsukov default: 246d8caf56eSAndrey V. Elsukov return (0); 247d8caf56eSAndrey V. Elsukov }; 248d8caf56eSAndrey V. Elsukov ip6->s6_addr8[8] = 0; 249d8caf56eSAndrey V. Elsukov return (1); 250d8caf56eSAndrey V. Elsukov } 251d8caf56eSAndrey V. Elsukov 252c402a01bSAndrey V. Elsukov static NAT64NOINLINE in_addr_t 253d8caf56eSAndrey V. Elsukov nat64_extract_ip4(struct in6_addr *ip6, int plen) 254d8caf56eSAndrey V. Elsukov { 255d8caf56eSAndrey V. Elsukov in_addr_t ia; 256d8caf56eSAndrey V. Elsukov 257d8caf56eSAndrey V. Elsukov /* 258d8caf56eSAndrey V. Elsukov * According to RFC 6052 p2.2: 259d8caf56eSAndrey V. Elsukov * IPv4-embedded IPv6 addresses are composed of a variable-length 260d8caf56eSAndrey V. Elsukov * prefix, the embedded IPv4 address, and a variable length suffix. 261d8caf56eSAndrey V. Elsukov * The suffix bits are reserved for future extensions and SHOULD 262d8caf56eSAndrey V. Elsukov * be set to zero. 263d8caf56eSAndrey V. Elsukov */ 264d8caf56eSAndrey V. Elsukov switch (plen) { 265d8caf56eSAndrey V. Elsukov case 32: 266d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || ip6->s6_addr32[2] != 0) 267d8caf56eSAndrey V. Elsukov goto badip6; 268d8caf56eSAndrey V. Elsukov break; 269d8caf56eSAndrey V. Elsukov case 40: 270d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || 271d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[2] & htonl(0xff00ffff)) != 0) 272d8caf56eSAndrey V. Elsukov goto badip6; 273d8caf56eSAndrey V. Elsukov break; 274d8caf56eSAndrey V. Elsukov case 48: 275d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || 276d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[2] & htonl(0xff0000ff)) != 0) 277d8caf56eSAndrey V. Elsukov goto badip6; 278d8caf56eSAndrey V. Elsukov break; 279d8caf56eSAndrey V. Elsukov case 56: 280d8caf56eSAndrey V. Elsukov if (ip6->s6_addr32[3] != 0 || ip6->s6_addr8[8] != 0) 281d8caf56eSAndrey V. Elsukov goto badip6; 282d8caf56eSAndrey V. Elsukov break; 283d8caf56eSAndrey V. Elsukov case 64: 284d8caf56eSAndrey V. Elsukov if (ip6->s6_addr8[8] != 0 || 285d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[3] & htonl(0x00ffffff)) != 0) 286d8caf56eSAndrey V. Elsukov goto badip6; 287d8caf56eSAndrey V. Elsukov }; 288d8caf56eSAndrey V. Elsukov switch (plen) { 289d8caf56eSAndrey V. Elsukov case 32: 290d8caf56eSAndrey V. Elsukov case 96: 291d8caf56eSAndrey V. Elsukov ia = ip6->s6_addr32[plen / 32]; 292d8caf56eSAndrey V. Elsukov break; 293d8caf56eSAndrey V. Elsukov case 40: 294d8caf56eSAndrey V. Elsukov case 48: 295d8caf56eSAndrey V. Elsukov case 56: 296d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 297d8caf56eSAndrey V. Elsukov ia = (ip6->s6_addr32[1] << (plen % 32)) | 298d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[2] >> (24 - plen % 32)); 299d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 300d8caf56eSAndrey V. Elsukov ia = (ip6->s6_addr32[1] >> (plen % 32)) | 301d8caf56eSAndrey V. Elsukov (ip6->s6_addr32[2] << (24 - plen % 32)); 302d8caf56eSAndrey V. Elsukov #endif 303d8caf56eSAndrey V. Elsukov break; 304d8caf56eSAndrey V. Elsukov case 64: 305d8caf56eSAndrey V. Elsukov #if BYTE_ORDER == BIG_ENDIAN 306d8caf56eSAndrey V. Elsukov ia = (ip6->s6_addr32[2] << 8) | (ip6->s6_addr32[3] >> 24); 307d8caf56eSAndrey V. Elsukov #elif BYTE_ORDER == LITTLE_ENDIAN 308d8caf56eSAndrey V. Elsukov ia = (ip6->s6_addr32[2] >> 8) | (ip6->s6_addr32[3] << 24); 309d8caf56eSAndrey V. Elsukov #endif 310d8caf56eSAndrey V. Elsukov break; 311d8caf56eSAndrey V. Elsukov default: 312d8caf56eSAndrey V. Elsukov return (0); 313d8caf56eSAndrey V. Elsukov }; 314d8caf56eSAndrey V. Elsukov if (nat64_check_ip4(ia) != 0 || 315d8caf56eSAndrey V. Elsukov nat64_check_private_ip4(ia) != 0) 316d8caf56eSAndrey V. Elsukov goto badip4; 317d8caf56eSAndrey V. Elsukov 318d8caf56eSAndrey V. Elsukov return (ia); 319d8caf56eSAndrey V. Elsukov badip4: 320d8caf56eSAndrey V. Elsukov DPRINTF(DP_GENERIC, "invalid destination address: %08x", ia); 321d8caf56eSAndrey V. Elsukov return (0); 322d8caf56eSAndrey V. Elsukov badip6: 323d8caf56eSAndrey V. Elsukov DPRINTF(DP_GENERIC, "invalid IPv4-embedded IPv6 address"); 324d8caf56eSAndrey V. Elsukov return (0); 325d8caf56eSAndrey V. Elsukov } 326d8caf56eSAndrey V. Elsukov #endif 327d8caf56eSAndrey V. Elsukov 328d8caf56eSAndrey V. Elsukov /* 329d8caf56eSAndrey V. Elsukov * According to RFC 1624 the equation for incremental checksum update is: 330d8caf56eSAndrey V. Elsukov * HC' = ~(~HC + ~m + m') -- [Eqn. 3] 331d8caf56eSAndrey V. Elsukov * HC' = HC - ~m - m' -- [Eqn. 4] 332d8caf56eSAndrey V. Elsukov * So, when we are replacing IPv4 addresses to IPv6, we 333d8caf56eSAndrey V. Elsukov * can assume, that new bytes previously were zeros, and vise versa - 334d8caf56eSAndrey V. Elsukov * when we replacing IPv6 addresses to IPv4, now unused bytes become 335d8caf56eSAndrey V. Elsukov * zeros. The payload length in pseudo header has bigger size, but one 336d8caf56eSAndrey V. Elsukov * half of it should be zero. Using the equation 4 we get: 337d8caf56eSAndrey V. Elsukov * HC' = HC - (~m0 + m0') -- m0 is first changed word 338d8caf56eSAndrey V. Elsukov * HC' = (HC - (~m0 + m0')) - (~m1 + m1') -- m1 is second changed word 339d8caf56eSAndrey V. Elsukov * HC' = HC - ~m0 - m0' - ~m1 - m1' - ... = 340d8caf56eSAndrey V. Elsukov * = HC - sum(~m[i] + m'[i]) 341d8caf56eSAndrey V. Elsukov * 342d8caf56eSAndrey V. Elsukov * The function result should be used as follows: 343d8caf56eSAndrey V. Elsukov * IPv6 to IPv4: HC' = cksum_add(HC, result) 344d8caf56eSAndrey V. Elsukov * IPv4 to IPv6: HC' = cksum_add(HC, ~result) 345d8caf56eSAndrey V. Elsukov */ 346c402a01bSAndrey V. Elsukov static NAT64NOINLINE uint16_t 347d8caf56eSAndrey V. Elsukov nat64_cksum_convert(struct ip6_hdr *ip6, struct ip *ip) 348d8caf56eSAndrey V. Elsukov { 349d8caf56eSAndrey V. Elsukov uint32_t sum; 350d8caf56eSAndrey V. Elsukov uint16_t *p; 351d8caf56eSAndrey V. Elsukov 352d8caf56eSAndrey V. Elsukov sum = ~ip->ip_src.s_addr >> 16; 353d8caf56eSAndrey V. Elsukov sum += ~ip->ip_src.s_addr & 0xffff; 354d8caf56eSAndrey V. Elsukov sum += ~ip->ip_dst.s_addr >> 16; 355d8caf56eSAndrey V. Elsukov sum += ~ip->ip_dst.s_addr & 0xffff; 356d8caf56eSAndrey V. Elsukov 357d8caf56eSAndrey V. Elsukov for (p = (uint16_t *)&ip6->ip6_src; 358d8caf56eSAndrey V. Elsukov p < (uint16_t *)(&ip6->ip6_src + 2); p++) 359d8caf56eSAndrey V. Elsukov sum += *p; 360d8caf56eSAndrey V. Elsukov 361d8caf56eSAndrey V. Elsukov while (sum >> 16) 362d8caf56eSAndrey V. Elsukov sum = (sum & 0xffff) + (sum >> 16); 363d8caf56eSAndrey V. Elsukov return (sum); 364d8caf56eSAndrey V. Elsukov } 365d8caf56eSAndrey V. Elsukov 366d8caf56eSAndrey V. Elsukov #if __FreeBSD_version < 1100000 367d8caf56eSAndrey V. Elsukov #define ip_fillid(ip) (ip)->ip_id = ip_newid() 368d8caf56eSAndrey V. Elsukov #endif 369c402a01bSAndrey V. Elsukov static NAT64NOINLINE void 370d8caf56eSAndrey V. Elsukov nat64_init_ip4hdr(const struct ip6_hdr *ip6, const struct ip6_frag *frag, 371d8caf56eSAndrey V. Elsukov uint16_t plen, uint8_t proto, struct ip *ip) 372d8caf56eSAndrey V. Elsukov { 373d8caf56eSAndrey V. Elsukov 374d8caf56eSAndrey V. Elsukov /* assume addresses are already initialized */ 375d8caf56eSAndrey V. Elsukov ip->ip_v = IPVERSION; 376d8caf56eSAndrey V. Elsukov ip->ip_hl = sizeof(*ip) >> 2; 377d8caf56eSAndrey V. Elsukov ip->ip_tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 378d8caf56eSAndrey V. Elsukov ip->ip_len = htons(sizeof(*ip) + plen); 379d8caf56eSAndrey V. Elsukov #ifdef IPFIREWALL_NAT64_DIRECT_OUTPUT 380d8caf56eSAndrey V. Elsukov ip->ip_ttl = ip6->ip6_hlim - IPV6_HLIMDEC; 381d8caf56eSAndrey V. Elsukov #else 382d8caf56eSAndrey V. Elsukov /* Forwarding code will decrement TTL. */ 383d8caf56eSAndrey V. Elsukov ip->ip_ttl = ip6->ip6_hlim; 384d8caf56eSAndrey V. Elsukov #endif 385d8caf56eSAndrey V. Elsukov ip->ip_sum = 0; 386d8caf56eSAndrey V. Elsukov ip->ip_p = (proto == IPPROTO_ICMPV6) ? IPPROTO_ICMP: proto; 387d8caf56eSAndrey V. Elsukov ip_fillid(ip); 388d8caf56eSAndrey V. Elsukov if (frag != NULL) { 389d8caf56eSAndrey V. Elsukov ip->ip_off = htons(ntohs(frag->ip6f_offlg) >> 3); 390d8caf56eSAndrey V. Elsukov if (frag->ip6f_offlg & IP6F_MORE_FRAG) 391d8caf56eSAndrey V. Elsukov ip->ip_off |= htons(IP_MF); 392d8caf56eSAndrey V. Elsukov } else { 393d8caf56eSAndrey V. Elsukov ip->ip_off = htons(IP_DF); 394d8caf56eSAndrey V. Elsukov } 395d8caf56eSAndrey V. Elsukov ip->ip_sum = in_cksum_hdr(ip); 396d8caf56eSAndrey V. Elsukov } 397d8caf56eSAndrey V. Elsukov 398d8caf56eSAndrey V. Elsukov #define FRAGSZ(mtu) ((mtu) - sizeof(struct ip6_hdr) - sizeof(struct ip6_frag)) 399c402a01bSAndrey V. Elsukov static NAT64NOINLINE int 400d8caf56eSAndrey V. Elsukov nat64_fragment6(nat64_stats_block *stats, struct ip6_hdr *ip6, struct mbufq *mq, 401d8caf56eSAndrey V. Elsukov struct mbuf *m, uint32_t mtu, uint16_t ip_id, uint16_t ip_off) 402d8caf56eSAndrey V. Elsukov { 403d8caf56eSAndrey V. Elsukov struct ip6_frag ip6f; 404d8caf56eSAndrey V. Elsukov struct mbuf *n; 405d8caf56eSAndrey V. Elsukov uint16_t hlen, len, offset; 406d8caf56eSAndrey V. Elsukov int plen; 407d8caf56eSAndrey V. Elsukov 408d8caf56eSAndrey V. Elsukov plen = ntohs(ip6->ip6_plen); 409d8caf56eSAndrey V. Elsukov hlen = sizeof(struct ip6_hdr); 410d8caf56eSAndrey V. Elsukov 411d8caf56eSAndrey V. Elsukov /* Fragmentation isn't needed */ 412d8caf56eSAndrey V. Elsukov if (ip_off == 0 && plen <= mtu - hlen) { 413d8caf56eSAndrey V. Elsukov M_PREPEND(m, hlen, M_NOWAIT); 414d8caf56eSAndrey V. Elsukov if (m == NULL) { 415d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 416d8caf56eSAndrey V. Elsukov return (ENOMEM); 417d8caf56eSAndrey V. Elsukov } 418d8caf56eSAndrey V. Elsukov bcopy(ip6, mtod(m, void *), hlen); 419d8caf56eSAndrey V. Elsukov if (mbufq_enqueue(mq, m) != 0) { 420d8caf56eSAndrey V. Elsukov m_freem(m); 421d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 422d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to mbufq overflow"); 423d8caf56eSAndrey V. Elsukov return (ENOBUFS); 424d8caf56eSAndrey V. Elsukov } 425d8caf56eSAndrey V. Elsukov return (0); 426d8caf56eSAndrey V. Elsukov } 427d8caf56eSAndrey V. Elsukov 428d8caf56eSAndrey V. Elsukov hlen += sizeof(struct ip6_frag); 429d8caf56eSAndrey V. Elsukov ip6f.ip6f_reserved = 0; 430d8caf56eSAndrey V. Elsukov ip6f.ip6f_nxt = ip6->ip6_nxt; 431d8caf56eSAndrey V. Elsukov ip6->ip6_nxt = IPPROTO_FRAGMENT; 432d8caf56eSAndrey V. Elsukov if (ip_off != 0) { 433d8caf56eSAndrey V. Elsukov /* 434d8caf56eSAndrey V. Elsukov * We have got an IPv4 fragment. 435d8caf56eSAndrey V. Elsukov * Use offset value and ip_id from original fragment. 436d8caf56eSAndrey V. Elsukov */ 437d8caf56eSAndrey V. Elsukov ip6f.ip6f_ident = htonl(ntohs(ip_id)); 438d8caf56eSAndrey V. Elsukov offset = (ntohs(ip_off) & IP_OFFMASK) << 3; 439d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, ifrags); 440d8caf56eSAndrey V. Elsukov } else { 441d8caf56eSAndrey V. Elsukov /* The packet size exceeds interface MTU */ 442d8caf56eSAndrey V. Elsukov ip6f.ip6f_ident = htonl(ip6_randomid()); 443d8caf56eSAndrey V. Elsukov offset = 0; /* First fragment*/ 444d8caf56eSAndrey V. Elsukov } 445d8caf56eSAndrey V. Elsukov while (plen > 0 && m != NULL) { 446d8caf56eSAndrey V. Elsukov n = NULL; 447d8caf56eSAndrey V. Elsukov len = FRAGSZ(mtu) & ~7; 448d8caf56eSAndrey V. Elsukov if (len > plen) 449d8caf56eSAndrey V. Elsukov len = plen; 450d8caf56eSAndrey V. Elsukov ip6->ip6_plen = htons(len + sizeof(ip6f)); 451d8caf56eSAndrey V. Elsukov ip6f.ip6f_offlg = ntohs(offset); 452d8caf56eSAndrey V. Elsukov if (len < plen || (ip_off & htons(IP_MF)) != 0) 453d8caf56eSAndrey V. Elsukov ip6f.ip6f_offlg |= IP6F_MORE_FRAG; 454d8caf56eSAndrey V. Elsukov offset += len; 455d8caf56eSAndrey V. Elsukov plen -= len; 456d8caf56eSAndrey V. Elsukov if (plen > 0) { 457d8caf56eSAndrey V. Elsukov n = m_split(m, len, M_NOWAIT); 458d8caf56eSAndrey V. Elsukov if (n == NULL) 459d8caf56eSAndrey V. Elsukov goto fail; 460d8caf56eSAndrey V. Elsukov } 461d8caf56eSAndrey V. Elsukov M_PREPEND(m, hlen, M_NOWAIT); 462d8caf56eSAndrey V. Elsukov if (m == NULL) 463d8caf56eSAndrey V. Elsukov goto fail; 464d8caf56eSAndrey V. Elsukov bcopy(ip6, mtod(m, void *), sizeof(struct ip6_hdr)); 465d8caf56eSAndrey V. Elsukov bcopy(&ip6f, mtodo(m, sizeof(struct ip6_hdr)), 466d8caf56eSAndrey V. Elsukov sizeof(struct ip6_frag)); 467d8caf56eSAndrey V. Elsukov if (mbufq_enqueue(mq, m) != 0) 468d8caf56eSAndrey V. Elsukov goto fail; 469d8caf56eSAndrey V. Elsukov m = n; 470d8caf56eSAndrey V. Elsukov } 471d8caf56eSAndrey V. Elsukov NAT64STAT_ADD(stats, ofrags, mbufq_len(mq)); 472d8caf56eSAndrey V. Elsukov return (0); 473d8caf56eSAndrey V. Elsukov fail: 474d8caf56eSAndrey V. Elsukov if (m != NULL) 475d8caf56eSAndrey V. Elsukov m_freem(m); 476d8caf56eSAndrey V. Elsukov if (n != NULL) 477d8caf56eSAndrey V. Elsukov m_freem(n); 478d8caf56eSAndrey V. Elsukov mbufq_drain(mq); 479d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 480d8caf56eSAndrey V. Elsukov return (ENOMEM); 481d8caf56eSAndrey V. Elsukov } 482d8caf56eSAndrey V. Elsukov 483c570565fSAndrey V. Elsukov static NAT64NOINLINE int 484c570565fSAndrey V. Elsukov nat64_find_route6(struct nhop6_basic *pnh, struct sockaddr_in6 *dst, 485c570565fSAndrey V. Elsukov struct mbuf *m) 486d8caf56eSAndrey V. Elsukov { 487d8caf56eSAndrey V. Elsukov 488c570565fSAndrey V. Elsukov if (fib6_lookup_nh_basic(M_GETFIB(m), &dst->sin6_addr, 0, 0, 0, 489c570565fSAndrey V. Elsukov pnh) != 0) 490c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 491c570565fSAndrey V. Elsukov if (pnh->nh_flags & (NHF_BLACKHOLE | NHF_REJECT)) 492c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 493c570565fSAndrey V. Elsukov /* 494c570565fSAndrey V. Elsukov * XXX: we need to use destination address with embedded scope 495c570565fSAndrey V. Elsukov * zone id, because LLTABLE uses such form of addresses for lookup. 496c570565fSAndrey V. Elsukov */ 497d8caf56eSAndrey V. Elsukov dst->sin6_family = AF_INET6; 498d8caf56eSAndrey V. Elsukov dst->sin6_len = sizeof(*dst); 499c570565fSAndrey V. Elsukov dst->sin6_addr = pnh->nh_addr; 500c570565fSAndrey V. Elsukov if (IN6_IS_SCOPE_LINKLOCAL(&dst->sin6_addr)) 501c570565fSAndrey V. Elsukov dst->sin6_addr.s6_addr16[1] = 502c570565fSAndrey V. Elsukov htons(pnh->nh_ifp->if_index & 0xffff); 503c570565fSAndrey V. Elsukov dst->sin6_port = 0; 504c570565fSAndrey V. Elsukov dst->sin6_scope_id = 0; 505c570565fSAndrey V. Elsukov dst->sin6_flowinfo = 0; 506c570565fSAndrey V. Elsukov 507c570565fSAndrey V. Elsukov return (0); 508d8caf56eSAndrey V. Elsukov } 509d8caf56eSAndrey V. Elsukov 510d8caf56eSAndrey V. Elsukov #define NAT64_ICMP6_PLEN 64 511c402a01bSAndrey V. Elsukov static NAT64NOINLINE void 512d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(struct mbuf *m, uint8_t type, uint8_t code, uint32_t mtu, 513d8caf56eSAndrey V. Elsukov nat64_stats_block *stats, void *logdata) 514d8caf56eSAndrey V. Elsukov { 515d8caf56eSAndrey V. Elsukov struct icmp6_hdr *icmp6; 516d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6, *oip6; 517d8caf56eSAndrey V. Elsukov struct mbuf *n; 518d8caf56eSAndrey V. Elsukov int len, plen; 519d8caf56eSAndrey V. Elsukov 520d8caf56eSAndrey V. Elsukov len = 0; 521d8caf56eSAndrey V. Elsukov plen = nat64_getlasthdr(m, &len); 522d8caf56eSAndrey V. Elsukov if (plen < 0) { 523d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "mbuf isn't contigious"); 524d8caf56eSAndrey V. Elsukov goto freeit; 525d8caf56eSAndrey V. Elsukov } 526d8caf56eSAndrey V. Elsukov /* 527d8caf56eSAndrey V. Elsukov * Do not send ICMPv6 in reply to ICMPv6 errors. 528d8caf56eSAndrey V. Elsukov */ 529d8caf56eSAndrey V. Elsukov if (plen == IPPROTO_ICMPV6) { 530d8caf56eSAndrey V. Elsukov if (m->m_len < len + sizeof(*icmp6)) { 531d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "mbuf isn't contigious"); 532d8caf56eSAndrey V. Elsukov goto freeit; 533d8caf56eSAndrey V. Elsukov } 534d8caf56eSAndrey V. Elsukov icmp6 = mtodo(m, len); 535d8caf56eSAndrey V. Elsukov if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST || 536d8caf56eSAndrey V. Elsukov icmp6->icmp6_type == ND_REDIRECT) { 537d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "do not send ICMPv6 in reply to " 538d8caf56eSAndrey V. Elsukov "ICMPv6 errors"); 539d8caf56eSAndrey V. Elsukov goto freeit; 540d8caf56eSAndrey V. Elsukov } 541d8caf56eSAndrey V. Elsukov } 542d8caf56eSAndrey V. Elsukov /* 543d8caf56eSAndrey V. Elsukov if (icmp6_ratelimit(&ip6->ip6_src, type, code)) 544d8caf56eSAndrey V. Elsukov goto freeit; 545d8caf56eSAndrey V. Elsukov */ 546d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 547d8caf56eSAndrey V. Elsukov switch (type) { 548d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH: 549d8caf56eSAndrey V. Elsukov case ICMP6_PACKET_TOO_BIG: 550d8caf56eSAndrey V. Elsukov case ICMP6_TIME_EXCEEDED: 551d8caf56eSAndrey V. Elsukov case ICMP6_PARAM_PROB: 552d8caf56eSAndrey V. Elsukov break; 553d8caf56eSAndrey V. Elsukov default: 554d8caf56eSAndrey V. Elsukov goto freeit; 555d8caf56eSAndrey V. Elsukov } 556d8caf56eSAndrey V. Elsukov /* Calculate length of ICMPv6 payload */ 557d8caf56eSAndrey V. Elsukov len = (m->m_pkthdr.len > NAT64_ICMP6_PLEN) ? NAT64_ICMP6_PLEN: 558d8caf56eSAndrey V. Elsukov m->m_pkthdr.len; 559d8caf56eSAndrey V. Elsukov 560d8caf56eSAndrey V. Elsukov /* Create new ICMPv6 datagram */ 561d8caf56eSAndrey V. Elsukov plen = len + sizeof(struct icmp6_hdr); 562d8caf56eSAndrey V. Elsukov n = m_get2(sizeof(struct ip6_hdr) + plen + max_hdr, M_NOWAIT, 563d8caf56eSAndrey V. Elsukov MT_HEADER, M_PKTHDR); 564d8caf56eSAndrey V. Elsukov if (n == NULL) { 565d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 566d8caf56eSAndrey V. Elsukov m_freem(m); 567d8caf56eSAndrey V. Elsukov return; 568d8caf56eSAndrey V. Elsukov } 569d8caf56eSAndrey V. Elsukov /* 570d8caf56eSAndrey V. Elsukov * Move pkthdr from original mbuf. We should have initialized some 571d8caf56eSAndrey V. Elsukov * fields, because we can reinject this mbuf to netisr and it will 572d8caf56eSAndrey V. Elsukov * go trough input path (it requires at least rcvif should be set). 573d8caf56eSAndrey V. Elsukov * Also do M_ALIGN() to reduce chances of need to allocate new mbuf 574d8caf56eSAndrey V. Elsukov * in the chain, when we will do M_PREPEND() or make some type of 575d8caf56eSAndrey V. Elsukov * tunneling. 576d8caf56eSAndrey V. Elsukov */ 577d8caf56eSAndrey V. Elsukov m_move_pkthdr(n, m); 578d8caf56eSAndrey V. Elsukov M_ALIGN(n, sizeof(struct ip6_hdr) + plen + max_hdr); 579d8caf56eSAndrey V. Elsukov 580d8caf56eSAndrey V. Elsukov n->m_len = n->m_pkthdr.len = sizeof(struct ip6_hdr) + plen; 581d8caf56eSAndrey V. Elsukov oip6 = mtod(n, struct ip6_hdr *); 582d8caf56eSAndrey V. Elsukov oip6->ip6_src = ip6->ip6_dst; 583d8caf56eSAndrey V. Elsukov oip6->ip6_dst = ip6->ip6_src; 584d8caf56eSAndrey V. Elsukov oip6->ip6_nxt = IPPROTO_ICMPV6; 585d8caf56eSAndrey V. Elsukov oip6->ip6_flow = 0; 586d8caf56eSAndrey V. Elsukov oip6->ip6_vfc |= IPV6_VERSION; 587d8caf56eSAndrey V. Elsukov oip6->ip6_hlim = V_ip6_defhlim; 588d8caf56eSAndrey V. Elsukov oip6->ip6_plen = htons(plen); 589d8caf56eSAndrey V. Elsukov 590d8caf56eSAndrey V. Elsukov icmp6 = mtodo(n, sizeof(struct ip6_hdr)); 591d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = 0; 592d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = type; 593d8caf56eSAndrey V. Elsukov icmp6->icmp6_code = code; 594d8caf56eSAndrey V. Elsukov icmp6->icmp6_mtu = htonl(mtu); 595d8caf56eSAndrey V. Elsukov 596d8caf56eSAndrey V. Elsukov m_copydata(m, 0, len, mtodo(n, sizeof(struct ip6_hdr) + 597d8caf56eSAndrey V. Elsukov sizeof(struct icmp6_hdr))); 598d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = in6_cksum(n, IPPROTO_ICMPV6, 599d8caf56eSAndrey V. Elsukov sizeof(struct ip6_hdr), plen); 600d8caf56eSAndrey V. Elsukov m_freem(m); 601d8caf56eSAndrey V. Elsukov nat64_output_one(n, stats, logdata); 602d8caf56eSAndrey V. Elsukov return; 603d8caf56eSAndrey V. Elsukov freeit: 604d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 605d8caf56eSAndrey V. Elsukov m_freem(m); 606d8caf56eSAndrey V. Elsukov } 607d8caf56eSAndrey V. Elsukov 608c570565fSAndrey V. Elsukov static NAT64NOINLINE int 609c570565fSAndrey V. Elsukov nat64_find_route4(struct nhop4_basic *pnh, struct sockaddr_in *dst, 610c570565fSAndrey V. Elsukov struct mbuf *m) 611d8caf56eSAndrey V. Elsukov { 612d8caf56eSAndrey V. Elsukov 613c570565fSAndrey V. Elsukov if (fib4_lookup_nh_basic(M_GETFIB(m), dst->sin_addr, 0, 0, pnh) != 0) 614c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 615c570565fSAndrey V. Elsukov if (pnh->nh_flags & (NHF_BLACKHOLE | NHF_BROADCAST | NHF_REJECT)) 616c570565fSAndrey V. Elsukov return (EHOSTUNREACH); 617c570565fSAndrey V. Elsukov 618d8caf56eSAndrey V. Elsukov dst->sin_family = AF_INET; 619d8caf56eSAndrey V. Elsukov dst->sin_len = sizeof(*dst); 620c570565fSAndrey V. Elsukov dst->sin_addr = pnh->nh_addr; 621c570565fSAndrey V. Elsukov dst->sin_port = 0; 622c570565fSAndrey V. Elsukov return (0); 623d8caf56eSAndrey V. Elsukov } 624d8caf56eSAndrey V. Elsukov 625d8caf56eSAndrey V. Elsukov #define NAT64_ICMP_PLEN 64 626c402a01bSAndrey V. Elsukov static NAT64NOINLINE void 627d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(struct mbuf *m, uint8_t type, 628d8caf56eSAndrey V. Elsukov uint8_t code, uint16_t mtu, nat64_stats_block *stats, void *logdata) 629d8caf56eSAndrey V. Elsukov { 630d8caf56eSAndrey V. Elsukov struct icmp *icmp; 631d8caf56eSAndrey V. Elsukov struct ip *ip, *oip; 632d8caf56eSAndrey V. Elsukov struct mbuf *n; 633d8caf56eSAndrey V. Elsukov int len, plen; 634d8caf56eSAndrey V. Elsukov 635d8caf56eSAndrey V. Elsukov ip = mtod(m, struct ip *); 636d8caf56eSAndrey V. Elsukov /* Do not send ICMP error if packet is not the first fragment */ 637d8caf56eSAndrey V. Elsukov if (ip->ip_off & ~ntohs(IP_MF|IP_DF)) { 638d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "not first fragment"); 639d8caf56eSAndrey V. Elsukov goto freeit; 640d8caf56eSAndrey V. Elsukov } 641d8caf56eSAndrey V. Elsukov /* Do not send ICMP in reply to ICMP errors */ 642d8caf56eSAndrey V. Elsukov if (ip->ip_p == IPPROTO_ICMP) { 643d8caf56eSAndrey V. Elsukov if (m->m_len < (ip->ip_hl << 2)) { 644d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "mbuf isn't contigious"); 645d8caf56eSAndrey V. Elsukov goto freeit; 646d8caf56eSAndrey V. Elsukov } 647d8caf56eSAndrey V. Elsukov icmp = mtodo(m, ip->ip_hl << 2); 648d8caf56eSAndrey V. Elsukov if (!ICMP_INFOTYPE(icmp->icmp_type)) { 649d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "do not send ICMP in reply to " 650d8caf56eSAndrey V. Elsukov "ICMP errors"); 651d8caf56eSAndrey V. Elsukov goto freeit; 652d8caf56eSAndrey V. Elsukov } 653d8caf56eSAndrey V. Elsukov } 654d8caf56eSAndrey V. Elsukov switch (type) { 655d8caf56eSAndrey V. Elsukov case ICMP_UNREACH: 656d8caf56eSAndrey V. Elsukov case ICMP_TIMXCEED: 657d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB: 658d8caf56eSAndrey V. Elsukov break; 659d8caf56eSAndrey V. Elsukov default: 660d8caf56eSAndrey V. Elsukov goto freeit; 661d8caf56eSAndrey V. Elsukov } 662d8caf56eSAndrey V. Elsukov /* Calculate length of ICMP payload */ 663d8caf56eSAndrey V. Elsukov len = (m->m_pkthdr.len > NAT64_ICMP_PLEN) ? (ip->ip_hl << 2) + 8: 664d8caf56eSAndrey V. Elsukov m->m_pkthdr.len; 665d8caf56eSAndrey V. Elsukov 666d8caf56eSAndrey V. Elsukov /* Create new ICMPv4 datagram */ 667d8caf56eSAndrey V. Elsukov plen = len + sizeof(struct icmphdr) + sizeof(uint32_t); 668d8caf56eSAndrey V. Elsukov n = m_get2(sizeof(struct ip) + plen + max_hdr, M_NOWAIT, 669d8caf56eSAndrey V. Elsukov MT_HEADER, M_PKTHDR); 670d8caf56eSAndrey V. Elsukov if (n == NULL) { 671d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 672d8caf56eSAndrey V. Elsukov m_freem(m); 673d8caf56eSAndrey V. Elsukov return; 674d8caf56eSAndrey V. Elsukov } 675d8caf56eSAndrey V. Elsukov m_move_pkthdr(n, m); 676d8caf56eSAndrey V. Elsukov M_ALIGN(n, sizeof(struct ip) + plen + max_hdr); 677d8caf56eSAndrey V. Elsukov 678d8caf56eSAndrey V. Elsukov n->m_len = n->m_pkthdr.len = sizeof(struct ip) + plen; 679d8caf56eSAndrey V. Elsukov oip = mtod(n, struct ip *); 680d8caf56eSAndrey V. Elsukov oip->ip_v = IPVERSION; 681d8caf56eSAndrey V. Elsukov oip->ip_hl = sizeof(struct ip) >> 2; 682d8caf56eSAndrey V. Elsukov oip->ip_tos = 0; 683d8caf56eSAndrey V. Elsukov oip->ip_len = htons(n->m_pkthdr.len); 684d8caf56eSAndrey V. Elsukov oip->ip_ttl = V_ip_defttl; 685d8caf56eSAndrey V. Elsukov oip->ip_p = IPPROTO_ICMP; 686d8caf56eSAndrey V. Elsukov ip_fillid(oip); 687d8caf56eSAndrey V. Elsukov oip->ip_off = htons(IP_DF); 688d8caf56eSAndrey V. Elsukov oip->ip_src = ip->ip_dst; 689d8caf56eSAndrey V. Elsukov oip->ip_dst = ip->ip_src; 690d8caf56eSAndrey V. Elsukov oip->ip_sum = 0; 691d8caf56eSAndrey V. Elsukov oip->ip_sum = in_cksum_hdr(oip); 692d8caf56eSAndrey V. Elsukov 693d8caf56eSAndrey V. Elsukov icmp = mtodo(n, sizeof(struct ip)); 694d8caf56eSAndrey V. Elsukov icmp->icmp_type = type; 695d8caf56eSAndrey V. Elsukov icmp->icmp_code = code; 696d8caf56eSAndrey V. Elsukov icmp->icmp_cksum = 0; 697d8caf56eSAndrey V. Elsukov icmp->icmp_pmvoid = 0; 698d8caf56eSAndrey V. Elsukov icmp->icmp_nextmtu = htons(mtu); 699d8caf56eSAndrey V. Elsukov m_copydata(m, 0, len, mtodo(n, sizeof(struct ip) + 700d8caf56eSAndrey V. Elsukov sizeof(struct icmphdr) + sizeof(uint32_t))); 701d8caf56eSAndrey V. Elsukov icmp->icmp_cksum = in_cksum_skip(n, sizeof(struct ip) + plen, 702d8caf56eSAndrey V. Elsukov sizeof(struct ip)); 703d8caf56eSAndrey V. Elsukov m_freem(m); 704d8caf56eSAndrey V. Elsukov nat64_output_one(n, stats, logdata); 705d8caf56eSAndrey V. Elsukov return; 706d8caf56eSAndrey V. Elsukov freeit: 707d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 708d8caf56eSAndrey V. Elsukov m_freem(m); 709d8caf56eSAndrey V. Elsukov } 710d8caf56eSAndrey V. Elsukov 711d8caf56eSAndrey V. Elsukov /* Translate ICMP echo request/reply into ICMPv6 */ 712d8caf56eSAndrey V. Elsukov static void 713d8caf56eSAndrey V. Elsukov nat64_icmp_handle_echo(struct ip6_hdr *ip6, struct icmp6_hdr *icmp6, 714d8caf56eSAndrey V. Elsukov uint16_t id, uint8_t type) 715d8caf56eSAndrey V. Elsukov { 716d8caf56eSAndrey V. Elsukov uint16_t old; 717d8caf56eSAndrey V. Elsukov 718d8caf56eSAndrey V. Elsukov old = *(uint16_t *)icmp6; /* save type+code in one word */ 719d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = type; 720d8caf56eSAndrey V. Elsukov /* Reflect ICMPv6 -> ICMPv4 type translation in the cksum */ 721d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = cksum_adjust(icmp6->icmp6_cksum, 722d8caf56eSAndrey V. Elsukov old, *(uint16_t *)icmp6); 723d8caf56eSAndrey V. Elsukov if (id != 0) { 724d8caf56eSAndrey V. Elsukov old = icmp6->icmp6_id; 725d8caf56eSAndrey V. Elsukov icmp6->icmp6_id = id; 726d8caf56eSAndrey V. Elsukov /* Reflect ICMP id translation in the cksum */ 727d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = cksum_adjust(icmp6->icmp6_cksum, 728d8caf56eSAndrey V. Elsukov old, id); 729d8caf56eSAndrey V. Elsukov } 730d8caf56eSAndrey V. Elsukov /* Reflect IPv6 pseudo header in the cksum */ 731d8caf56eSAndrey V. Elsukov icmp6->icmp6_cksum = ~in6_cksum_pseudo(ip6, ntohs(ip6->ip6_plen), 732d8caf56eSAndrey V. Elsukov IPPROTO_ICMPV6, ~icmp6->icmp6_cksum); 733d8caf56eSAndrey V. Elsukov } 734d8caf56eSAndrey V. Elsukov 735c402a01bSAndrey V. Elsukov static NAT64NOINLINE struct mbuf * 736d8caf56eSAndrey V. Elsukov nat64_icmp_translate(struct mbuf *m, struct ip6_hdr *ip6, uint16_t icmpid, 737d8caf56eSAndrey V. Elsukov int offset, nat64_stats_block *stats) 738d8caf56eSAndrey V. Elsukov { 739d8caf56eSAndrey V. Elsukov struct ip ip; 740d8caf56eSAndrey V. Elsukov struct icmp *icmp; 741d8caf56eSAndrey V. Elsukov struct tcphdr *tcp; 742d8caf56eSAndrey V. Elsukov struct udphdr *udp; 743d8caf56eSAndrey V. Elsukov struct ip6_hdr *eip6; 744d8caf56eSAndrey V. Elsukov struct mbuf *n; 745d8caf56eSAndrey V. Elsukov uint32_t mtu; 746d8caf56eSAndrey V. Elsukov int len, hlen, plen; 747d8caf56eSAndrey V. Elsukov uint8_t type, code; 748d8caf56eSAndrey V. Elsukov 749d8caf56eSAndrey V. Elsukov if (m->m_len < offset + ICMP_MINLEN) 750d8caf56eSAndrey V. Elsukov m = m_pullup(m, offset + ICMP_MINLEN); 751d8caf56eSAndrey V. Elsukov if (m == NULL) { 752d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 753d8caf56eSAndrey V. Elsukov return (m); 754d8caf56eSAndrey V. Elsukov } 755d8caf56eSAndrey V. Elsukov mtu = 0; 756d8caf56eSAndrey V. Elsukov icmp = mtodo(m, offset); 757d8caf56eSAndrey V. Elsukov /* RFC 7915 p4.2 */ 758d8caf56eSAndrey V. Elsukov switch (icmp->icmp_type) { 759d8caf56eSAndrey V. Elsukov case ICMP_ECHOREPLY: 760d8caf56eSAndrey V. Elsukov type = ICMP6_ECHO_REPLY; 761d8caf56eSAndrey V. Elsukov code = 0; 762d8caf56eSAndrey V. Elsukov break; 763d8caf56eSAndrey V. Elsukov case ICMP_UNREACH: 764d8caf56eSAndrey V. Elsukov type = ICMP6_DST_UNREACH; 765d8caf56eSAndrey V. Elsukov switch (icmp->icmp_code) { 766d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NET: 767d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_HOST: 768d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_SRCFAIL: 769d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NET_UNKNOWN: 770d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_HOST_UNKNOWN: 771d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_TOSNET: 772d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_TOSHOST: 773d8caf56eSAndrey V. Elsukov code = ICMP6_DST_UNREACH_NOROUTE; 774d8caf56eSAndrey V. Elsukov break; 775d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_PROTOCOL: 776d8caf56eSAndrey V. Elsukov type = ICMP6_PARAM_PROB; 777d8caf56eSAndrey V. Elsukov code = ICMP6_PARAMPROB_NEXTHEADER; 778d8caf56eSAndrey V. Elsukov break; 779d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_PORT: 780d8caf56eSAndrey V. Elsukov code = ICMP6_DST_UNREACH_NOPORT; 781d8caf56eSAndrey V. Elsukov break; 782d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NEEDFRAG: 783d8caf56eSAndrey V. Elsukov type = ICMP6_PACKET_TOO_BIG; 784d8caf56eSAndrey V. Elsukov code = 0; 785d8caf56eSAndrey V. Elsukov /* XXX: needs an additional look */ 786d8caf56eSAndrey V. Elsukov mtu = max(IPV6_MMTU, ntohs(icmp->icmp_nextmtu) + 20); 787d8caf56eSAndrey V. Elsukov break; 788d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_NET_PROHIB: 789d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_HOST_PROHIB: 790d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_FILTER_PROHIB: 791d8caf56eSAndrey V. Elsukov case ICMP_UNREACH_PRECEDENCE_CUTOFF: 792d8caf56eSAndrey V. Elsukov code = ICMP6_DST_UNREACH_ADMIN; 793d8caf56eSAndrey V. Elsukov break; 794d8caf56eSAndrey V. Elsukov default: 795d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d, code %d", 796d8caf56eSAndrey V. Elsukov icmp->icmp_type, icmp->icmp_code); 797d8caf56eSAndrey V. Elsukov goto freeit; 798d8caf56eSAndrey V. Elsukov } 799d8caf56eSAndrey V. Elsukov break; 800d8caf56eSAndrey V. Elsukov case ICMP_TIMXCEED: 801d8caf56eSAndrey V. Elsukov type = ICMP6_TIME_EXCEEDED; 802d8caf56eSAndrey V. Elsukov code = icmp->icmp_code; 803d8caf56eSAndrey V. Elsukov break; 804d8caf56eSAndrey V. Elsukov case ICMP_ECHO: 805d8caf56eSAndrey V. Elsukov type = ICMP6_ECHO_REQUEST; 806d8caf56eSAndrey V. Elsukov code = 0; 807d8caf56eSAndrey V. Elsukov break; 808d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB: 809d8caf56eSAndrey V. Elsukov type = ICMP6_PARAM_PROB; 810d8caf56eSAndrey V. Elsukov switch (icmp->icmp_code) { 811d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB_ERRATPTR: 812d8caf56eSAndrey V. Elsukov case ICMP_PARAMPROB_LENGTH: 813d8caf56eSAndrey V. Elsukov code = ICMP6_PARAMPROB_HEADER; 814d8caf56eSAndrey V. Elsukov switch (icmp->icmp_pptr) { 815d8caf56eSAndrey V. Elsukov case 0: /* Version/IHL */ 816d8caf56eSAndrey V. Elsukov case 1: /* Type Of Service */ 817d8caf56eSAndrey V. Elsukov mtu = icmp->icmp_pptr; 818d8caf56eSAndrey V. Elsukov break; 819d8caf56eSAndrey V. Elsukov case 2: /* Total Length */ 820d8caf56eSAndrey V. Elsukov case 3: mtu = 4; /* Payload Length */ 821d8caf56eSAndrey V. Elsukov break; 822d8caf56eSAndrey V. Elsukov case 8: /* Time to Live */ 823d8caf56eSAndrey V. Elsukov mtu = 7; /* Hop Limit */ 824d8caf56eSAndrey V. Elsukov break; 825d8caf56eSAndrey V. Elsukov case 9: /* Protocol */ 826d8caf56eSAndrey V. Elsukov mtu = 6; /* Next Header */ 827d8caf56eSAndrey V. Elsukov break; 828d8caf56eSAndrey V. Elsukov case 12: /* Source address */ 829d8caf56eSAndrey V. Elsukov case 13: 830d8caf56eSAndrey V. Elsukov case 14: 831d8caf56eSAndrey V. Elsukov case 15: 832d8caf56eSAndrey V. Elsukov mtu = 8; 833d8caf56eSAndrey V. Elsukov break; 834d8caf56eSAndrey V. Elsukov case 16: /* Destination address */ 835d8caf56eSAndrey V. Elsukov case 17: 836d8caf56eSAndrey V. Elsukov case 18: 837d8caf56eSAndrey V. Elsukov case 19: 838d8caf56eSAndrey V. Elsukov mtu = 24; 839d8caf56eSAndrey V. Elsukov break; 840d8caf56eSAndrey V. Elsukov default: /* Silently drop */ 841d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d," 842d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp->icmp_type, 843d8caf56eSAndrey V. Elsukov icmp->icmp_code, icmp->icmp_pptr); 844d8caf56eSAndrey V. Elsukov goto freeit; 845d8caf56eSAndrey V. Elsukov } 846d8caf56eSAndrey V. Elsukov break; 847d8caf56eSAndrey V. Elsukov default: 848d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d," 849d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp->icmp_type, 850d8caf56eSAndrey V. Elsukov icmp->icmp_code, icmp->icmp_pptr); 851d8caf56eSAndrey V. Elsukov goto freeit; 852d8caf56eSAndrey V. Elsukov } 853d8caf56eSAndrey V. Elsukov break; 854d8caf56eSAndrey V. Elsukov default: 855d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMP type %d, code %d", 856d8caf56eSAndrey V. Elsukov icmp->icmp_type, icmp->icmp_code); 857d8caf56eSAndrey V. Elsukov goto freeit; 858d8caf56eSAndrey V. Elsukov } 859d8caf56eSAndrey V. Elsukov /* 860d8caf56eSAndrey V. Elsukov * For echo request/reply we can use original payload, 861d8caf56eSAndrey V. Elsukov * but we need adjust icmp_cksum, because ICMPv6 cksum covers 862d8caf56eSAndrey V. Elsukov * IPv6 pseudo header and ICMPv6 types differs from ICMPv4. 863d8caf56eSAndrey V. Elsukov */ 864d8caf56eSAndrey V. Elsukov if (type == ICMP6_ECHO_REQUEST || type == ICMP6_ECHO_REPLY) { 865d8caf56eSAndrey V. Elsukov nat64_icmp_handle_echo(ip6, ICMP6(icmp), icmpid, type); 866d8caf56eSAndrey V. Elsukov return (m); 867d8caf56eSAndrey V. Elsukov } 868d8caf56eSAndrey V. Elsukov /* 869d8caf56eSAndrey V. Elsukov * For other types of ICMP messages we need to translate inner 870d8caf56eSAndrey V. Elsukov * IPv4 header to IPv6 header. 871d8caf56eSAndrey V. Elsukov * Assume ICMP src is the same as payload dst 872d8caf56eSAndrey V. Elsukov * E.g. we have ( GWsrc1 , NATIP1 ) in outer header 873d8caf56eSAndrey V. Elsukov * and ( NATIP1, Hostdst1 ) in ICMP copy header. 874d8caf56eSAndrey V. Elsukov * In that case, we already have map for NATIP1 and GWsrc1. 875d8caf56eSAndrey V. Elsukov * The only thing we need is to copy IPv6 map prefix to 876d8caf56eSAndrey V. Elsukov * Hostdst1. 877d8caf56eSAndrey V. Elsukov */ 878d8caf56eSAndrey V. Elsukov hlen = offset + ICMP_MINLEN; 879d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + sizeof(struct ip) + ICMP_MINLEN) { 880d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Message is too short %d", 881d8caf56eSAndrey V. Elsukov m->m_pkthdr.len); 882d8caf56eSAndrey V. Elsukov goto freeit; 883d8caf56eSAndrey V. Elsukov } 884d8caf56eSAndrey V. Elsukov m_copydata(m, hlen, sizeof(struct ip), (char *)&ip); 885d8caf56eSAndrey V. Elsukov if (ip.ip_v != IPVERSION) { 886d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Wrong IP version %d", ip.ip_v); 887d8caf56eSAndrey V. Elsukov goto freeit; 888d8caf56eSAndrey V. Elsukov } 889d8caf56eSAndrey V. Elsukov hlen += ip.ip_hl << 2; /* Skip inner IP header */ 890d8caf56eSAndrey V. Elsukov if (nat64_check_ip4(ip.ip_src.s_addr) != 0 || 891d8caf56eSAndrey V. Elsukov nat64_check_ip4(ip.ip_dst.s_addr) != 0 || 892d8caf56eSAndrey V. Elsukov nat64_check_private_ip4(ip.ip_src.s_addr) != 0 || 893d8caf56eSAndrey V. Elsukov nat64_check_private_ip4(ip.ip_dst.s_addr) != 0) { 894d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "IP addresses checks failed %04x -> %04x", 895d8caf56eSAndrey V. Elsukov ntohl(ip.ip_src.s_addr), ntohl(ip.ip_dst.s_addr)); 896d8caf56eSAndrey V. Elsukov goto freeit; 897d8caf56eSAndrey V. Elsukov } 898d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + ICMP_MINLEN) { 899d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Message is too short %d", 900d8caf56eSAndrey V. Elsukov m->m_pkthdr.len); 901d8caf56eSAndrey V. Elsukov goto freeit; 902d8caf56eSAndrey V. Elsukov } 903d8caf56eSAndrey V. Elsukov #if 0 904d8caf56eSAndrey V. Elsukov /* 905d8caf56eSAndrey V. Elsukov * Check that inner source matches the outer destination. 906d8caf56eSAndrey V. Elsukov * XXX: We need some method to convert IPv4 into IPv6 address here, 907d8caf56eSAndrey V. Elsukov * and compare IPv6 addresses. 908d8caf56eSAndrey V. Elsukov */ 909d8caf56eSAndrey V. Elsukov if (ip.ip_src.s_addr != nat64_get_ip4(&ip6->ip6_dst)) { 910d8caf56eSAndrey V. Elsukov DPRINTF(DP_GENERIC, "Inner source doesn't match destination ", 911d8caf56eSAndrey V. Elsukov "%04x vs %04x", ip.ip_src.s_addr, 912d8caf56eSAndrey V. Elsukov nat64_get_ip4(&ip6->ip6_dst)); 913d8caf56eSAndrey V. Elsukov goto freeit; 914d8caf56eSAndrey V. Elsukov } 915d8caf56eSAndrey V. Elsukov #endif 916d8caf56eSAndrey V. Elsukov /* 917d8caf56eSAndrey V. Elsukov * Create new mbuf for ICMPv6 datagram. 918d8caf56eSAndrey V. Elsukov * NOTE: len is data length just after inner IP header. 919d8caf56eSAndrey V. Elsukov */ 920d8caf56eSAndrey V. Elsukov len = m->m_pkthdr.len - hlen; 921d8caf56eSAndrey V. Elsukov if (sizeof(struct ip6_hdr) + 922d8caf56eSAndrey V. Elsukov sizeof(struct icmp6_hdr) + len > NAT64_ICMP6_PLEN) 923d8caf56eSAndrey V. Elsukov len = NAT64_ICMP6_PLEN - sizeof(struct icmp6_hdr) - 924d8caf56eSAndrey V. Elsukov sizeof(struct ip6_hdr); 925d8caf56eSAndrey V. Elsukov plen = sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr) + len; 926d8caf56eSAndrey V. Elsukov n = m_get2(offset + plen + max_hdr, M_NOWAIT, MT_HEADER, M_PKTHDR); 927d8caf56eSAndrey V. Elsukov if (n == NULL) { 928d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 929d8caf56eSAndrey V. Elsukov m_freem(m); 930d8caf56eSAndrey V. Elsukov return (NULL); 931d8caf56eSAndrey V. Elsukov } 932d8caf56eSAndrey V. Elsukov m_move_pkthdr(n, m); 933d8caf56eSAndrey V. Elsukov M_ALIGN(n, offset + plen + max_hdr); 934d8caf56eSAndrey V. Elsukov n->m_len = n->m_pkthdr.len = offset + plen; 935d8caf56eSAndrey V. Elsukov /* Adjust ip6_plen in outer header */ 936d8caf56eSAndrey V. Elsukov ip6->ip6_plen = htons(plen); 937d8caf56eSAndrey V. Elsukov /* Construct new inner IPv6 header */ 938d8caf56eSAndrey V. Elsukov eip6 = mtodo(n, offset + sizeof(struct icmp6_hdr)); 939d8caf56eSAndrey V. Elsukov eip6->ip6_src = ip6->ip6_dst; 940d8caf56eSAndrey V. Elsukov /* Use the fact that we have single /96 prefix for IPv4 map */ 941d8caf56eSAndrey V. Elsukov eip6->ip6_dst = ip6->ip6_src; 942d8caf56eSAndrey V. Elsukov nat64_set_ip4(&eip6->ip6_dst, ip.ip_dst.s_addr); 943d8caf56eSAndrey V. Elsukov 944d8caf56eSAndrey V. Elsukov eip6->ip6_flow = htonl(ip.ip_tos << 20); 945d8caf56eSAndrey V. Elsukov eip6->ip6_vfc |= IPV6_VERSION; 946d8caf56eSAndrey V. Elsukov eip6->ip6_hlim = ip.ip_ttl; 947d8caf56eSAndrey V. Elsukov eip6->ip6_plen = htons(ntohs(ip.ip_len) - (ip.ip_hl << 2)); 948d8caf56eSAndrey V. Elsukov eip6->ip6_nxt = (ip.ip_p == IPPROTO_ICMP) ? IPPROTO_ICMPV6: ip.ip_p; 949d8caf56eSAndrey V. Elsukov m_copydata(m, hlen, len, (char *)(eip6 + 1)); 950d8caf56eSAndrey V. Elsukov /* 951d8caf56eSAndrey V. Elsukov * We need to translate source port in the inner ULP header, 952d8caf56eSAndrey V. Elsukov * and adjust ULP checksum. 953d8caf56eSAndrey V. Elsukov */ 954d8caf56eSAndrey V. Elsukov switch (ip.ip_p) { 955d8caf56eSAndrey V. Elsukov case IPPROTO_TCP: 956d8caf56eSAndrey V. Elsukov if (len < offsetof(struct tcphdr, th_sum)) 957d8caf56eSAndrey V. Elsukov break; 958d8caf56eSAndrey V. Elsukov tcp = TCP(eip6 + 1); 959d8caf56eSAndrey V. Elsukov if (icmpid != 0) { 960d8caf56eSAndrey V. Elsukov tcp->th_sum = cksum_adjust(tcp->th_sum, 961d8caf56eSAndrey V. Elsukov tcp->th_sport, icmpid); 962d8caf56eSAndrey V. Elsukov tcp->th_sport = icmpid; 963d8caf56eSAndrey V. Elsukov } 964d8caf56eSAndrey V. Elsukov tcp->th_sum = cksum_add(tcp->th_sum, 965d8caf56eSAndrey V. Elsukov ~nat64_cksum_convert(eip6, &ip)); 966d8caf56eSAndrey V. Elsukov break; 967d8caf56eSAndrey V. Elsukov case IPPROTO_UDP: 968d8caf56eSAndrey V. Elsukov if (len < offsetof(struct udphdr, uh_sum)) 969d8caf56eSAndrey V. Elsukov break; 970d8caf56eSAndrey V. Elsukov udp = UDP(eip6 + 1); 971d8caf56eSAndrey V. Elsukov if (icmpid != 0) { 972d8caf56eSAndrey V. Elsukov udp->uh_sum = cksum_adjust(udp->uh_sum, 973d8caf56eSAndrey V. Elsukov udp->uh_sport, icmpid); 974d8caf56eSAndrey V. Elsukov udp->uh_sport = icmpid; 975d8caf56eSAndrey V. Elsukov } 976d8caf56eSAndrey V. Elsukov udp->uh_sum = cksum_add(udp->uh_sum, 977d8caf56eSAndrey V. Elsukov ~nat64_cksum_convert(eip6, &ip)); 978d8caf56eSAndrey V. Elsukov break; 979d8caf56eSAndrey V. Elsukov case IPPROTO_ICMP: 980d8caf56eSAndrey V. Elsukov /* 981d8caf56eSAndrey V. Elsukov * Check if this is an ICMP error message for echo request 982d8caf56eSAndrey V. Elsukov * that we sent. I.e. ULP in the data containing invoking 983d8caf56eSAndrey V. Elsukov * packet is IPPROTO_ICMP and its type is ICMP_ECHO. 984d8caf56eSAndrey V. Elsukov */ 985d8caf56eSAndrey V. Elsukov icmp = (struct icmp *)(eip6 + 1); 986d8caf56eSAndrey V. Elsukov if (icmp->icmp_type != ICMP_ECHO) { 987d8caf56eSAndrey V. Elsukov m_freem(n); 988d8caf56eSAndrey V. Elsukov goto freeit; 989d8caf56eSAndrey V. Elsukov } 990d8caf56eSAndrey V. Elsukov /* 991d8caf56eSAndrey V. Elsukov * For our client this original datagram should looks 992d8caf56eSAndrey V. Elsukov * like it was ICMPv6 datagram with type ICMP6_ECHO_REQUEST. 993d8caf56eSAndrey V. Elsukov * Thus we need adjust icmp_cksum and convert type from 994d8caf56eSAndrey V. Elsukov * ICMP_ECHO to ICMP6_ECHO_REQUEST. 995d8caf56eSAndrey V. Elsukov */ 996d8caf56eSAndrey V. Elsukov nat64_icmp_handle_echo(eip6, ICMP6(icmp), icmpid, 997d8caf56eSAndrey V. Elsukov ICMP6_ECHO_REQUEST); 998d8caf56eSAndrey V. Elsukov } 999d8caf56eSAndrey V. Elsukov m_freem(m); 1000d8caf56eSAndrey V. Elsukov /* Convert ICMPv4 into ICMPv6 header */ 1001d8caf56eSAndrey V. Elsukov icmp = mtodo(n, offset); 1002d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_type = type; 1003d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_code = code; 1004d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_mtu = htonl(mtu); 1005d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_cksum = 0; 1006d8caf56eSAndrey V. Elsukov ICMP6(icmp)->icmp6_cksum = cksum_add( 1007d8caf56eSAndrey V. Elsukov ~in6_cksum_pseudo(ip6, plen, IPPROTO_ICMPV6, 0), 1008d8caf56eSAndrey V. Elsukov in_cksum_skip(n, n->m_pkthdr.len, offset)); 1009d8caf56eSAndrey V. Elsukov return (n); 1010d8caf56eSAndrey V. Elsukov freeit: 1011d8caf56eSAndrey V. Elsukov m_freem(m); 1012d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1013d8caf56eSAndrey V. Elsukov return (NULL); 1014d8caf56eSAndrey V. Elsukov } 1015d8caf56eSAndrey V. Elsukov 1016d8caf56eSAndrey V. Elsukov int 1017d8caf56eSAndrey V. Elsukov nat64_getlasthdr(struct mbuf *m, int *offset) 1018d8caf56eSAndrey V. Elsukov { 1019d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6; 1020d8caf56eSAndrey V. Elsukov struct ip6_hbh *hbh; 1021d8caf56eSAndrey V. Elsukov int proto, hlen; 1022d8caf56eSAndrey V. Elsukov 1023d8caf56eSAndrey V. Elsukov if (offset != NULL) 1024d8caf56eSAndrey V. Elsukov hlen = *offset; 1025d8caf56eSAndrey V. Elsukov else 1026d8caf56eSAndrey V. Elsukov hlen = 0; 1027d8caf56eSAndrey V. Elsukov 1028d8caf56eSAndrey V. Elsukov if (m->m_len < hlen + sizeof(*ip6)) 1029d8caf56eSAndrey V. Elsukov return (-1); 1030d8caf56eSAndrey V. Elsukov 1031d8caf56eSAndrey V. Elsukov ip6 = mtodo(m, hlen); 1032d8caf56eSAndrey V. Elsukov hlen += sizeof(*ip6); 1033d8caf56eSAndrey V. Elsukov proto = ip6->ip6_nxt; 1034d8caf56eSAndrey V. Elsukov /* Skip extension headers */ 1035d8caf56eSAndrey V. Elsukov while (proto == IPPROTO_HOPOPTS || proto == IPPROTO_ROUTING || 1036d8caf56eSAndrey V. Elsukov proto == IPPROTO_DSTOPTS) { 1037d8caf56eSAndrey V. Elsukov hbh = mtodo(m, hlen); 1038d8caf56eSAndrey V. Elsukov /* 1039d8caf56eSAndrey V. Elsukov * We expect mbuf has contigious data up to 1040d8caf56eSAndrey V. Elsukov * upper level header. 1041d8caf56eSAndrey V. Elsukov */ 1042d8caf56eSAndrey V. Elsukov if (m->m_len < hlen) 1043d8caf56eSAndrey V. Elsukov return (-1); 1044d8caf56eSAndrey V. Elsukov /* 1045d8caf56eSAndrey V. Elsukov * We doesn't support Jumbo payload option, 1046d8caf56eSAndrey V. Elsukov * so return error. 1047d8caf56eSAndrey V. Elsukov */ 1048d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_HOPOPTS && ip6->ip6_plen == 0) 1049d8caf56eSAndrey V. Elsukov return (-1); 1050d8caf56eSAndrey V. Elsukov proto = hbh->ip6h_nxt; 1051785c0d4dSAndrey V. Elsukov hlen += (hbh->ip6h_len + 1) << 3; 1052d8caf56eSAndrey V. Elsukov } 1053d8caf56eSAndrey V. Elsukov if (offset != NULL) 1054d8caf56eSAndrey V. Elsukov *offset = hlen; 1055d8caf56eSAndrey V. Elsukov return (proto); 1056d8caf56eSAndrey V. Elsukov } 1057d8caf56eSAndrey V. Elsukov 1058d8caf56eSAndrey V. Elsukov int 1059d8caf56eSAndrey V. Elsukov nat64_do_handle_ip4(struct mbuf *m, struct in6_addr *saddr, 1060d8caf56eSAndrey V. Elsukov struct in6_addr *daddr, uint16_t lport, nat64_stats_block *stats, 1061d8caf56eSAndrey V. Elsukov void *logdata) 1062d8caf56eSAndrey V. Elsukov { 1063c570565fSAndrey V. Elsukov struct nhop6_basic nh; 1064d8caf56eSAndrey V. Elsukov struct ip6_hdr ip6; 1065c570565fSAndrey V. Elsukov struct sockaddr_in6 dst; 1066d8caf56eSAndrey V. Elsukov struct ip *ip; 1067d8caf56eSAndrey V. Elsukov struct mbufq mq; 1068d8caf56eSAndrey V. Elsukov uint16_t ip_id, ip_off; 1069d8caf56eSAndrey V. Elsukov uint16_t *csum; 1070d8caf56eSAndrey V. Elsukov int plen, hlen; 1071d8caf56eSAndrey V. Elsukov uint8_t proto; 1072d8caf56eSAndrey V. Elsukov 1073d8caf56eSAndrey V. Elsukov ip = mtod(m, struct ip*); 1074d8caf56eSAndrey V. Elsukov 1075d8caf56eSAndrey V. Elsukov if (ip->ip_ttl <= IPTTLDEC) { 1076d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_TIMXCEED, 1077d8caf56eSAndrey V. Elsukov ICMP_TIMXCEED_INTRANS, 0, stats, logdata); 1078d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1079d8caf56eSAndrey V. Elsukov } 1080d8caf56eSAndrey V. Elsukov 1081d8caf56eSAndrey V. Elsukov ip6.ip6_dst = *daddr; 1082d8caf56eSAndrey V. Elsukov ip6.ip6_src = *saddr; 1083d8caf56eSAndrey V. Elsukov 1084d8caf56eSAndrey V. Elsukov hlen = ip->ip_hl << 2; 1085d8caf56eSAndrey V. Elsukov plen = ntohs(ip->ip_len) - hlen; 1086d8caf56eSAndrey V. Elsukov proto = ip->ip_p; 1087d8caf56eSAndrey V. Elsukov 1088d8caf56eSAndrey V. Elsukov /* Save ip_id and ip_off, both are in network byte order */ 1089d8caf56eSAndrey V. Elsukov ip_id = ip->ip_id; 1090d8caf56eSAndrey V. Elsukov ip_off = ip->ip_off & htons(IP_OFFMASK | IP_MF); 1091d8caf56eSAndrey V. Elsukov 1092d8caf56eSAndrey V. Elsukov /* Fragment length must be multiple of 8 octets */ 1093d8caf56eSAndrey V. Elsukov if ((ip->ip_off & htons(IP_MF)) != 0 && (plen & 0x7) != 0) { 1094d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_PARAMPROB, 1095d8caf56eSAndrey V. Elsukov ICMP_PARAMPROB_LENGTH, 0, stats, logdata); 1096d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1097d8caf56eSAndrey V. Elsukov } 1098d8caf56eSAndrey V. Elsukov /* Fragmented ICMP is unsupported */ 1099d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_ICMP && ip_off != 0) { 1100d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to fragmented ICMP"); 1101d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1102d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1103d8caf56eSAndrey V. Elsukov } 1104d8caf56eSAndrey V. Elsukov 1105c570565fSAndrey V. Elsukov dst.sin6_addr = ip6.ip6_dst; 1106c570565fSAndrey V. Elsukov if (nat64_find_route6(&nh, &dst, m) != 0) { 1107d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, noroute6); 1108d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 1109d8caf56eSAndrey V. Elsukov stats, logdata); 1110d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1111d8caf56eSAndrey V. Elsukov } 1112c570565fSAndrey V. Elsukov if (nh.nh_mtu < plen + sizeof(ip6) && 1113c570565fSAndrey V. Elsukov (ip->ip_off & htons(IP_DF)) != 0) { 1114d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 1115c570565fSAndrey V. Elsukov FRAGSZ(nh.nh_mtu) + sizeof(struct ip), stats, logdata); 1116d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1117d8caf56eSAndrey V. Elsukov } 1118d8caf56eSAndrey V. Elsukov 1119d8caf56eSAndrey V. Elsukov ip6.ip6_flow = htonl(ip->ip_tos << 20); 1120d8caf56eSAndrey V. Elsukov ip6.ip6_vfc |= IPV6_VERSION; 1121d8caf56eSAndrey V. Elsukov #ifdef IPFIREWALL_NAT64_DIRECT_OUTPUT 1122d8caf56eSAndrey V. Elsukov ip6.ip6_hlim = ip->ip_ttl - IPTTLDEC; 1123d8caf56eSAndrey V. Elsukov #else 1124d8caf56eSAndrey V. Elsukov /* Forwarding code will decrement HLIM. */ 1125d8caf56eSAndrey V. Elsukov ip6.ip6_hlim = ip->ip_ttl; 1126d8caf56eSAndrey V. Elsukov #endif 1127d8caf56eSAndrey V. Elsukov ip6.ip6_plen = htons(plen); 1128d8caf56eSAndrey V. Elsukov ip6.ip6_nxt = (proto == IPPROTO_ICMP) ? IPPROTO_ICMPV6: proto; 1129d8caf56eSAndrey V. Elsukov /* Convert checksums. */ 1130d8caf56eSAndrey V. Elsukov switch (proto) { 1131d8caf56eSAndrey V. Elsukov case IPPROTO_TCP: 1132d8caf56eSAndrey V. Elsukov csum = &TCP(mtodo(m, hlen))->th_sum; 1133d8caf56eSAndrey V. Elsukov if (lport != 0) { 1134d8caf56eSAndrey V. Elsukov struct tcphdr *tcp = TCP(mtodo(m, hlen)); 1135d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, tcp->th_dport, lport); 1136d8caf56eSAndrey V. Elsukov tcp->th_dport = lport; 1137d8caf56eSAndrey V. Elsukov } 1138d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, ~nat64_cksum_convert(&ip6, ip)); 1139d8caf56eSAndrey V. Elsukov break; 1140d8caf56eSAndrey V. Elsukov case IPPROTO_UDP: 1141d8caf56eSAndrey V. Elsukov csum = &UDP(mtodo(m, hlen))->uh_sum; 1142d8caf56eSAndrey V. Elsukov if (lport != 0) { 1143d8caf56eSAndrey V. Elsukov struct udphdr *udp = UDP(mtodo(m, hlen)); 1144d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, udp->uh_dport, lport); 1145d8caf56eSAndrey V. Elsukov udp->uh_dport = lport; 1146d8caf56eSAndrey V. Elsukov } 1147d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, ~nat64_cksum_convert(&ip6, ip)); 1148d8caf56eSAndrey V. Elsukov break; 1149d8caf56eSAndrey V. Elsukov case IPPROTO_ICMP: 1150d8caf56eSAndrey V. Elsukov m = nat64_icmp_translate(m, &ip6, lport, hlen, stats); 1151c570565fSAndrey V. Elsukov if (m == NULL) /* stats already accounted */ 1152d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1153d8caf56eSAndrey V. Elsukov } 1154d8caf56eSAndrey V. Elsukov 1155d8caf56eSAndrey V. Elsukov m_adj(m, hlen); 1156d8caf56eSAndrey V. Elsukov mbufq_init(&mq, 255); 1157c570565fSAndrey V. Elsukov nat64_fragment6(stats, &ip6, &mq, m, nh.nh_mtu, ip_id, ip_off); 1158d8caf56eSAndrey V. Elsukov while ((m = mbufq_dequeue(&mq)) != NULL) { 1159c570565fSAndrey V. Elsukov if (nat64_output(nh.nh_ifp, m, (struct sockaddr *)&dst, 1160c570565fSAndrey V. Elsukov NULL, stats, logdata) != 0) 1161d8caf56eSAndrey V. Elsukov break; 1162d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, opcnt46); 1163d8caf56eSAndrey V. Elsukov } 1164d8caf56eSAndrey V. Elsukov mbufq_drain(&mq); 1165d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1166d8caf56eSAndrey V. Elsukov } 1167d8caf56eSAndrey V. Elsukov 1168d8caf56eSAndrey V. Elsukov int 1169d8caf56eSAndrey V. Elsukov nat64_handle_icmp6(struct mbuf *m, int hlen, uint32_t aaddr, uint16_t aport, 1170d8caf56eSAndrey V. Elsukov nat64_stats_block *stats, void *logdata) 1171d8caf56eSAndrey V. Elsukov { 1172d8caf56eSAndrey V. Elsukov struct ip ip; 1173d8caf56eSAndrey V. Elsukov struct icmp6_hdr *icmp6; 1174d8caf56eSAndrey V. Elsukov struct ip6_frag *ip6f; 1175d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6, *ip6i; 1176d8caf56eSAndrey V. Elsukov uint32_t mtu; 1177d8caf56eSAndrey V. Elsukov int plen, proto; 1178d8caf56eSAndrey V. Elsukov uint8_t type, code; 1179d8caf56eSAndrey V. Elsukov 1180d8caf56eSAndrey V. Elsukov if (hlen == 0) { 1181d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 1182d8caf56eSAndrey V. Elsukov if (nat64_check_ip6(&ip6->ip6_src) != 0 || 1183d8caf56eSAndrey V. Elsukov nat64_check_ip6(&ip6->ip6_dst) != 0) 1184d8caf56eSAndrey V. Elsukov return (NAT64SKIP); 1185d8caf56eSAndrey V. Elsukov 1186d8caf56eSAndrey V. Elsukov proto = nat64_getlasthdr(m, &hlen); 1187d8caf56eSAndrey V. Elsukov if (proto != IPPROTO_ICMPV6) { 1188d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, 1189d8caf56eSAndrey V. Elsukov "dropped due to mbuf isn't contigious"); 1190d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1191d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1192d8caf56eSAndrey V. Elsukov } 1193d8caf56eSAndrey V. Elsukov } 1194d8caf56eSAndrey V. Elsukov 1195d8caf56eSAndrey V. Elsukov /* 1196d8caf56eSAndrey V. Elsukov * Translate ICMPv6 type and code to ICMPv4 (RFC7915). 1197d8caf56eSAndrey V. Elsukov * NOTE: ICMPv6 echo handled by nat64_do_handle_ip6(). 1198d8caf56eSAndrey V. Elsukov */ 1199d8caf56eSAndrey V. Elsukov icmp6 = mtodo(m, hlen); 1200d8caf56eSAndrey V. Elsukov mtu = 0; 1201d8caf56eSAndrey V. Elsukov switch (icmp6->icmp6_type) { 1202d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH: 1203d8caf56eSAndrey V. Elsukov type = ICMP_UNREACH; 1204d8caf56eSAndrey V. Elsukov switch (icmp6->icmp6_code) { 1205d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_NOROUTE: 1206d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_BEYONDSCOPE: 1207d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_ADDR: 1208d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_HOST; 1209d8caf56eSAndrey V. Elsukov break; 1210d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_ADMIN: 1211d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_HOST_PROHIB; 1212d8caf56eSAndrey V. Elsukov break; 1213d8caf56eSAndrey V. Elsukov case ICMP6_DST_UNREACH_NOPORT: 1214d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_PORT; 1215d8caf56eSAndrey V. Elsukov break; 1216d8caf56eSAndrey V. Elsukov default: 1217d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d," 1218d8caf56eSAndrey V. Elsukov " code %d", icmp6->icmp6_type, 1219d8caf56eSAndrey V. Elsukov icmp6->icmp6_code); 1220d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1221d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1222d8caf56eSAndrey V. Elsukov } 1223d8caf56eSAndrey V. Elsukov break; 1224d8caf56eSAndrey V. Elsukov case ICMP6_PACKET_TOO_BIG: 1225d8caf56eSAndrey V. Elsukov type = ICMP_UNREACH; 1226d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_NEEDFRAG; 1227d8caf56eSAndrey V. Elsukov mtu = ntohl(icmp6->icmp6_mtu); 1228d8caf56eSAndrey V. Elsukov if (mtu < IPV6_MMTU) { 1229d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Wrong MTU %d in ICMPv6 type %d," 1230d8caf56eSAndrey V. Elsukov " code %d", mtu, icmp6->icmp6_type, 1231d8caf56eSAndrey V. Elsukov icmp6->icmp6_code); 1232d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1233d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1234d8caf56eSAndrey V. Elsukov } 1235d8caf56eSAndrey V. Elsukov /* 1236d8caf56eSAndrey V. Elsukov * Adjust MTU to reflect difference between 1237d8caf56eSAndrey V. Elsukov * IPv6 an IPv4 headers. 1238d8caf56eSAndrey V. Elsukov */ 1239d8caf56eSAndrey V. Elsukov mtu -= sizeof(struct ip6_hdr) - sizeof(struct ip); 1240d8caf56eSAndrey V. Elsukov break; 1241c5f2dbb6SAndrey V. Elsukov case ICMP6_TIME_EXCEEDED: 1242d8caf56eSAndrey V. Elsukov type = ICMP_TIMXCEED; 1243c5f2dbb6SAndrey V. Elsukov code = icmp6->icmp6_code; 1244d8caf56eSAndrey V. Elsukov break; 1245d8caf56eSAndrey V. Elsukov case ICMP6_PARAM_PROB: 1246d8caf56eSAndrey V. Elsukov switch (icmp6->icmp6_code) { 1247d8caf56eSAndrey V. Elsukov case ICMP6_PARAMPROB_HEADER: 1248d8caf56eSAndrey V. Elsukov type = ICMP_PARAMPROB; 1249d8caf56eSAndrey V. Elsukov code = ICMP_PARAMPROB_ERRATPTR; 1250d8caf56eSAndrey V. Elsukov mtu = ntohl(icmp6->icmp6_pptr); 1251d8caf56eSAndrey V. Elsukov switch (mtu) { 1252d8caf56eSAndrey V. Elsukov case 0: /* Version/Traffic Class */ 1253d8caf56eSAndrey V. Elsukov case 1: /* Traffic Class/Flow Label */ 1254d8caf56eSAndrey V. Elsukov break; 1255d8caf56eSAndrey V. Elsukov case 4: /* Payload Length */ 1256d8caf56eSAndrey V. Elsukov case 5: 1257d8caf56eSAndrey V. Elsukov mtu = 2; 1258d8caf56eSAndrey V. Elsukov break; 1259d8caf56eSAndrey V. Elsukov case 6: /* Next Header */ 1260d8caf56eSAndrey V. Elsukov mtu = 9; 1261d8caf56eSAndrey V. Elsukov break; 1262d8caf56eSAndrey V. Elsukov case 7: /* Hop Limit */ 1263d8caf56eSAndrey V. Elsukov mtu = 8; 1264d8caf56eSAndrey V. Elsukov break; 1265d8caf56eSAndrey V. Elsukov default: 1266d8caf56eSAndrey V. Elsukov if (mtu >= 8 && mtu <= 23) { 1267d8caf56eSAndrey V. Elsukov mtu = 12; /* Source address */ 1268d8caf56eSAndrey V. Elsukov break; 1269d8caf56eSAndrey V. Elsukov } 1270d8caf56eSAndrey V. Elsukov if (mtu >= 24 && mtu <= 39) { 1271d8caf56eSAndrey V. Elsukov mtu = 16; /* Destination address */ 1272d8caf56eSAndrey V. Elsukov break; 1273d8caf56eSAndrey V. Elsukov } 1274d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d," 1275d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp6->icmp6_type, 1276d8caf56eSAndrey V. Elsukov icmp6->icmp6_code, mtu); 1277d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1278d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1279d8caf56eSAndrey V. Elsukov } 1280d8caf56eSAndrey V. Elsukov case ICMP6_PARAMPROB_NEXTHEADER: 1281d8caf56eSAndrey V. Elsukov type = ICMP_UNREACH; 1282d8caf56eSAndrey V. Elsukov code = ICMP_UNREACH_PROTOCOL; 1283d8caf56eSAndrey V. Elsukov break; 1284d8caf56eSAndrey V. Elsukov default: 1285d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d," 1286d8caf56eSAndrey V. Elsukov " code %d, pptr %d", icmp6->icmp6_type, 1287d8caf56eSAndrey V. Elsukov icmp6->icmp6_code, ntohl(icmp6->icmp6_pptr)); 1288d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1289d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1290d8caf56eSAndrey V. Elsukov } 1291d8caf56eSAndrey V. Elsukov break; 1292d8caf56eSAndrey V. Elsukov default: 1293d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported ICMPv6 type %d, code %d", 1294d8caf56eSAndrey V. Elsukov icmp6->icmp6_type, icmp6->icmp6_code); 1295d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1296d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1297d8caf56eSAndrey V. Elsukov } 1298d8caf56eSAndrey V. Elsukov 1299d8caf56eSAndrey V. Elsukov hlen += sizeof(struct icmp6_hdr); 1300d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + sizeof(struct ip6_hdr) + ICMP_MINLEN) { 1301d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1302d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Message is too short %d", 1303d8caf56eSAndrey V. Elsukov m->m_pkthdr.len); 1304d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1305d8caf56eSAndrey V. Elsukov } 1306d8caf56eSAndrey V. Elsukov /* 1307d8caf56eSAndrey V. Elsukov * We need at least ICMP_MINLEN bytes of original datagram payload 1308d8caf56eSAndrey V. Elsukov * to generate ICMP message. It is nice that ICMP_MINLEN is equal 1309d8caf56eSAndrey V. Elsukov * to sizeof(struct ip6_frag). So, if embedded datagram had a fragment 1310d8caf56eSAndrey V. Elsukov * header we will not have to do m_pullup() again. 1311d8caf56eSAndrey V. Elsukov * 1312d8caf56eSAndrey V. Elsukov * What we have here: 1313d8caf56eSAndrey V. Elsukov * Outer header: (IPv6iGW, v4mapPRefix+v4exthost) 1314d8caf56eSAndrey V. Elsukov * Inner header: (v4mapPRefix+v4host, IPv6iHost) [sport, dport] 1315d8caf56eSAndrey V. Elsukov * We need to translate it to: 1316d8caf56eSAndrey V. Elsukov * 1317d8caf56eSAndrey V. Elsukov * Outer header: (alias_host, v4exthost) 1318d8caf56eSAndrey V. Elsukov * Inner header: (v4exthost, alias_host) [sport, alias_port] 1319d8caf56eSAndrey V. Elsukov * 1320d8caf56eSAndrey V. Elsukov * Assume caller function has checked if v4mapPRefix+v4host 1321d8caf56eSAndrey V. Elsukov * matches configured prefix. 1322d8caf56eSAndrey V. Elsukov * The only two things we should be provided with are mapping between 1323d8caf56eSAndrey V. Elsukov * IPv6iHost <> alias_host and between dport and alias_port. 1324d8caf56eSAndrey V. Elsukov */ 1325d8caf56eSAndrey V. Elsukov if (m->m_len < hlen + sizeof(struct ip6_hdr) + ICMP_MINLEN) 1326d8caf56eSAndrey V. Elsukov m = m_pullup(m, hlen + sizeof(struct ip6_hdr) + ICMP_MINLEN); 1327d8caf56eSAndrey V. Elsukov if (m == NULL) { 1328d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, nomem); 1329d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1330d8caf56eSAndrey V. Elsukov } 1331d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 1332d8caf56eSAndrey V. Elsukov ip6i = mtodo(m, hlen); 1333d8caf56eSAndrey V. Elsukov ip6f = NULL; 1334d8caf56eSAndrey V. Elsukov proto = ip6i->ip6_nxt; 1335d8caf56eSAndrey V. Elsukov plen = ntohs(ip6i->ip6_plen); 1336d8caf56eSAndrey V. Elsukov hlen += sizeof(struct ip6_hdr); 1337d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_FRAGMENT) { 1338d8caf56eSAndrey V. Elsukov if (m->m_pkthdr.len < hlen + sizeof(struct ip6_frag) + 1339d8caf56eSAndrey V. Elsukov ICMP_MINLEN) 1340d8caf56eSAndrey V. Elsukov goto fail; 1341d8caf56eSAndrey V. Elsukov ip6f = mtodo(m, hlen); 1342d8caf56eSAndrey V. Elsukov proto = ip6f->ip6f_nxt; 1343d8caf56eSAndrey V. Elsukov plen -= sizeof(struct ip6_frag); 1344d8caf56eSAndrey V. Elsukov hlen += sizeof(struct ip6_frag); 1345d8caf56eSAndrey V. Elsukov /* Ajust MTU to reflect frag header size */ 1346d8caf56eSAndrey V. Elsukov if (type == ICMP_UNREACH && code == ICMP_UNREACH_NEEDFRAG) 1347d8caf56eSAndrey V. Elsukov mtu -= sizeof(struct ip6_frag); 1348d8caf56eSAndrey V. Elsukov } 1349d8caf56eSAndrey V. Elsukov if (proto != IPPROTO_TCP && proto != IPPROTO_UDP) { 1350d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Unsupported proto %d in the inner header", 1351d8caf56eSAndrey V. Elsukov proto); 1352d8caf56eSAndrey V. Elsukov goto fail; 1353d8caf56eSAndrey V. Elsukov } 1354d8caf56eSAndrey V. Elsukov if (nat64_check_ip6(&ip6i->ip6_src) != 0 || 1355d8caf56eSAndrey V. Elsukov nat64_check_ip6(&ip6i->ip6_dst) != 0) { 1356d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Inner addresses do not passes the check"); 1357d8caf56eSAndrey V. Elsukov goto fail; 1358d8caf56eSAndrey V. Elsukov } 1359d8caf56eSAndrey V. Elsukov /* Check if outer dst is the same as inner src */ 1360d8caf56eSAndrey V. Elsukov if (!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &ip6i->ip6_src)) { 1361d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "Inner src doesn't match outer dst"); 1362d8caf56eSAndrey V. Elsukov goto fail; 1363d8caf56eSAndrey V. Elsukov } 1364d8caf56eSAndrey V. Elsukov 1365d8caf56eSAndrey V. Elsukov /* Now we need to make a fake IPv4 packet to generate ICMP message */ 1366d8caf56eSAndrey V. Elsukov ip.ip_dst.s_addr = aaddr; 1367d8caf56eSAndrey V. Elsukov ip.ip_src.s_addr = nat64_get_ip4(&ip6i->ip6_src); 1368d8caf56eSAndrey V. Elsukov /* XXX: Make fake ulp header */ 1369d8caf56eSAndrey V. Elsukov #ifdef IPFIREWALL_NAT64_DIRECT_OUTPUT 1370d8caf56eSAndrey V. Elsukov ip6i->ip6_hlim += IPV6_HLIMDEC; /* init_ip4hdr will decrement it */ 1371d8caf56eSAndrey V. Elsukov #endif 1372d8caf56eSAndrey V. Elsukov nat64_init_ip4hdr(ip6i, ip6f, plen, proto, &ip); 1373d8caf56eSAndrey V. Elsukov m_adj(m, hlen - sizeof(struct ip)); 1374d8caf56eSAndrey V. Elsukov bcopy(&ip, mtod(m, void *), sizeof(ip)); 1375d8caf56eSAndrey V. Elsukov nat64_icmp_reflect(m, type, code, (uint16_t)mtu, stats, logdata); 1376d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1377d8caf56eSAndrey V. Elsukov fail: 1378d8caf56eSAndrey V. Elsukov /* 1379d8caf56eSAndrey V. Elsukov * We must call m_freem() because mbuf pointer could be 1380d8caf56eSAndrey V. Elsukov * changed with m_pullup(). 1381d8caf56eSAndrey V. Elsukov */ 1382d8caf56eSAndrey V. Elsukov m_freem(m); 1383d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1384d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1385d8caf56eSAndrey V. Elsukov } 1386d8caf56eSAndrey V. Elsukov 1387d8caf56eSAndrey V. Elsukov int 1388d8caf56eSAndrey V. Elsukov nat64_do_handle_ip6(struct mbuf *m, uint32_t aaddr, uint16_t aport, 1389d8caf56eSAndrey V. Elsukov nat64_stats_block *stats, void *logdata) 1390d8caf56eSAndrey V. Elsukov { 1391d8caf56eSAndrey V. Elsukov struct ip ip; 1392c570565fSAndrey V. Elsukov struct nhop4_basic nh; 1393c570565fSAndrey V. Elsukov struct sockaddr_in dst; 1394d8caf56eSAndrey V. Elsukov struct ip6_frag *frag; 1395d8caf56eSAndrey V. Elsukov struct ip6_hdr *ip6; 1396d8caf56eSAndrey V. Elsukov struct icmp6_hdr *icmp6; 1397d8caf56eSAndrey V. Elsukov uint16_t *csum; 1398db68f783SBjoern A. Zeeb int plen, hlen, proto; 1399d8caf56eSAndrey V. Elsukov 1400d8caf56eSAndrey V. Elsukov /* 1401d8caf56eSAndrey V. Elsukov * XXX: we expect ipfw_chk() did m_pullup() up to upper level 1402d8caf56eSAndrey V. Elsukov * protocol's headers. Also we skip some checks, that ip6_input(), 1403d8caf56eSAndrey V. Elsukov * ip6_forward(), ip6_fastfwd() and ipfw_chk() already did. 1404d8caf56eSAndrey V. Elsukov */ 1405d8caf56eSAndrey V. Elsukov ip6 = mtod(m, struct ip6_hdr *); 1406d8caf56eSAndrey V. Elsukov if (nat64_check_ip6(&ip6->ip6_src) != 0 || 1407d8caf56eSAndrey V. Elsukov nat64_check_ip6(&ip6->ip6_dst) != 0) { 1408d8caf56eSAndrey V. Elsukov return (NAT64SKIP); 1409d8caf56eSAndrey V. Elsukov } 1410d8caf56eSAndrey V. Elsukov 1411d8caf56eSAndrey V. Elsukov /* Starting from this point we must not return zero */ 1412d8caf56eSAndrey V. Elsukov ip.ip_src.s_addr = aaddr; 1413d8caf56eSAndrey V. Elsukov if (nat64_check_ip4(ip.ip_src.s_addr) != 0) { 1414d8caf56eSAndrey V. Elsukov DPRINTF(DP_GENERIC, "invalid source address: %08x", 1415d8caf56eSAndrey V. Elsukov ip.ip_src.s_addr); 1416d8caf56eSAndrey V. Elsukov /* XXX: stats? */ 1417d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1418d8caf56eSAndrey V. Elsukov } 1419d8caf56eSAndrey V. Elsukov 1420d8caf56eSAndrey V. Elsukov ip.ip_dst.s_addr = nat64_get_ip4(&ip6->ip6_dst); 1421d8caf56eSAndrey V. Elsukov if (ip.ip_dst.s_addr == 0) { 1422d8caf56eSAndrey V. Elsukov /* XXX: stats? */ 1423d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1424d8caf56eSAndrey V. Elsukov } 1425d8caf56eSAndrey V. Elsukov 1426d8caf56eSAndrey V. Elsukov if (ip6->ip6_hlim <= IPV6_HLIMDEC) { 1427d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_TIME_EXCEEDED, 1428d8caf56eSAndrey V. Elsukov ICMP6_TIME_EXCEED_TRANSIT, 0, stats, logdata); 1429d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1430d8caf56eSAndrey V. Elsukov } 1431d8caf56eSAndrey V. Elsukov 1432d8caf56eSAndrey V. Elsukov hlen = 0; 1433d8caf56eSAndrey V. Elsukov plen = ntohs(ip6->ip6_plen); 1434d8caf56eSAndrey V. Elsukov proto = nat64_getlasthdr(m, &hlen); 1435d8caf56eSAndrey V. Elsukov if (proto < 0) { 1436d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to mbuf isn't contigious"); 1437d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1438d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1439d8caf56eSAndrey V. Elsukov } 1440d8caf56eSAndrey V. Elsukov frag = NULL; 1441d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_FRAGMENT) { 1442d8caf56eSAndrey V. Elsukov /* ipfw_chk should m_pullup up to frag header */ 1443d8caf56eSAndrey V. Elsukov if (m->m_len < hlen + sizeof(*frag)) { 1444d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, 1445d8caf56eSAndrey V. Elsukov "dropped due to mbuf isn't contigious"); 1446d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1447d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1448d8caf56eSAndrey V. Elsukov } 1449d8caf56eSAndrey V. Elsukov frag = mtodo(m, hlen); 1450d8caf56eSAndrey V. Elsukov proto = frag->ip6f_nxt; 1451d8caf56eSAndrey V. Elsukov hlen += sizeof(*frag); 1452d8caf56eSAndrey V. Elsukov /* Fragmented ICMPv6 is unsupported */ 1453d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_ICMPV6) { 1454d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "dropped due to fragmented ICMPv6"); 1455d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1456d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1457d8caf56eSAndrey V. Elsukov } 1458d8caf56eSAndrey V. Elsukov /* Fragment length must be multiple of 8 octets */ 1459d8caf56eSAndrey V. Elsukov if ((frag->ip6f_offlg & IP6F_MORE_FRAG) != 0 && 1460d8caf56eSAndrey V. Elsukov ((plen + sizeof(struct ip6_hdr) - hlen) & 0x7) != 0) { 1461d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_PARAM_PROB, 1462d8caf56eSAndrey V. Elsukov ICMP6_PARAMPROB_HEADER, 1463d8caf56eSAndrey V. Elsukov offsetof(struct ip6_hdr, ip6_plen), stats, 1464d8caf56eSAndrey V. Elsukov logdata); 1465d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1466d8caf56eSAndrey V. Elsukov } 1467d8caf56eSAndrey V. Elsukov } 1468d8caf56eSAndrey V. Elsukov plen -= hlen - sizeof(struct ip6_hdr); 1469d8caf56eSAndrey V. Elsukov if (plen < 0 || m->m_pkthdr.len < plen + hlen) { 1470d8caf56eSAndrey V. Elsukov DPRINTF(DP_DROPS, "plen %d, pkthdr.len %d, hlen %d", 1471d8caf56eSAndrey V. Elsukov plen, m->m_pkthdr.len, hlen); 1472d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, dropped); 1473d8caf56eSAndrey V. Elsukov return (NAT64MFREE); 1474d8caf56eSAndrey V. Elsukov } 1475d8caf56eSAndrey V. Elsukov 1476d8caf56eSAndrey V. Elsukov icmp6 = NULL; /* Make gcc happy */ 1477d8caf56eSAndrey V. Elsukov if (proto == IPPROTO_ICMPV6) { 1478d8caf56eSAndrey V. Elsukov icmp6 = mtodo(m, hlen); 1479d8caf56eSAndrey V. Elsukov if (icmp6->icmp6_type != ICMP6_ECHO_REQUEST && 1480d8caf56eSAndrey V. Elsukov icmp6->icmp6_type != ICMP6_ECHO_REPLY) 1481d8caf56eSAndrey V. Elsukov return (nat64_handle_icmp6(m, hlen, aaddr, aport, 1482d8caf56eSAndrey V. Elsukov stats, logdata)); 1483d8caf56eSAndrey V. Elsukov } 1484c570565fSAndrey V. Elsukov dst.sin_addr.s_addr = ip.ip_dst.s_addr; 1485c570565fSAndrey V. Elsukov if (nat64_find_route4(&nh, &dst, m) != 0) { 1486d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, noroute4); 1487d8caf56eSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_DST_UNREACH, 1488d8caf56eSAndrey V. Elsukov ICMP6_DST_UNREACH_NOROUTE, 0, stats, logdata); 1489d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1490d8caf56eSAndrey V. Elsukov } 1491c570565fSAndrey V. Elsukov if (nh.nh_mtu < plen + sizeof(ip)) { 1492c570565fSAndrey V. Elsukov nat64_icmp6_reflect(m, ICMP6_PACKET_TOO_BIG, 0, nh.nh_mtu, 1493c570565fSAndrey V. Elsukov stats, logdata); 1494d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1495d8caf56eSAndrey V. Elsukov } 1496d8caf56eSAndrey V. Elsukov nat64_init_ip4hdr(ip6, frag, plen, proto, &ip); 1497d8caf56eSAndrey V. Elsukov /* Convert checksums. */ 1498d8caf56eSAndrey V. Elsukov switch (proto) { 1499d8caf56eSAndrey V. Elsukov case IPPROTO_TCP: 1500d8caf56eSAndrey V. Elsukov csum = &TCP(mtodo(m, hlen))->th_sum; 1501d8caf56eSAndrey V. Elsukov if (aport != 0) { 1502d8caf56eSAndrey V. Elsukov struct tcphdr *tcp = TCP(mtodo(m, hlen)); 1503d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, tcp->th_sport, aport); 1504d8caf56eSAndrey V. Elsukov tcp->th_sport = aport; 1505d8caf56eSAndrey V. Elsukov } 1506d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, nat64_cksum_convert(ip6, &ip)); 1507d8caf56eSAndrey V. Elsukov break; 1508d8caf56eSAndrey V. Elsukov case IPPROTO_UDP: 1509d8caf56eSAndrey V. Elsukov csum = &UDP(mtodo(m, hlen))->uh_sum; 1510d8caf56eSAndrey V. Elsukov if (aport != 0) { 1511d8caf56eSAndrey V. Elsukov struct udphdr *udp = UDP(mtodo(m, hlen)); 1512d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, udp->uh_sport, aport); 1513d8caf56eSAndrey V. Elsukov udp->uh_sport = aport; 1514d8caf56eSAndrey V. Elsukov } 1515d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, nat64_cksum_convert(ip6, &ip)); 1516d8caf56eSAndrey V. Elsukov break; 1517d8caf56eSAndrey V. Elsukov case IPPROTO_ICMPV6: 1518d8caf56eSAndrey V. Elsukov /* Checksum in ICMPv6 covers pseudo header */ 1519d8caf56eSAndrey V. Elsukov csum = &icmp6->icmp6_cksum; 1520d8caf56eSAndrey V. Elsukov *csum = cksum_add(*csum, in6_cksum_pseudo(ip6, plen, 1521d8caf56eSAndrey V. Elsukov IPPROTO_ICMPV6, 0)); 1522d8caf56eSAndrey V. Elsukov /* Convert ICMPv6 types to ICMP */ 1523c570565fSAndrey V. Elsukov proto = *(uint16_t *)icmp6; /* save old word for cksum_adjust */ 1524d8caf56eSAndrey V. Elsukov if (icmp6->icmp6_type == ICMP6_ECHO_REQUEST) 1525d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = ICMP_ECHO; 1526d8caf56eSAndrey V. Elsukov else /* ICMP6_ECHO_REPLY */ 1527d8caf56eSAndrey V. Elsukov icmp6->icmp6_type = ICMP_ECHOREPLY; 1528c570565fSAndrey V. Elsukov *csum = cksum_adjust(*csum, (uint16_t)proto, 1529c570565fSAndrey V. Elsukov *(uint16_t *)icmp6); 1530d8caf56eSAndrey V. Elsukov if (aport != 0) { 1531d8caf56eSAndrey V. Elsukov uint16_t old_id = icmp6->icmp6_id; 1532d8caf56eSAndrey V. Elsukov icmp6->icmp6_id = aport; 1533d8caf56eSAndrey V. Elsukov *csum = cksum_adjust(*csum, old_id, aport); 1534d8caf56eSAndrey V. Elsukov } 1535d8caf56eSAndrey V. Elsukov break; 1536d8caf56eSAndrey V. Elsukov }; 1537d8caf56eSAndrey V. Elsukov 1538d8caf56eSAndrey V. Elsukov m_adj(m, hlen - sizeof(ip)); 1539d8caf56eSAndrey V. Elsukov bcopy(&ip, mtod(m, void *), sizeof(ip)); 1540c570565fSAndrey V. Elsukov if (nat64_output(nh.nh_ifp, m, (struct sockaddr *)&dst, NULL, 1541c570565fSAndrey V. Elsukov stats, logdata) == 0) 1542d8caf56eSAndrey V. Elsukov NAT64STAT_INC(stats, opcnt64); 1543d8caf56eSAndrey V. Elsukov return (NAT64RETURN); 1544d8caf56eSAndrey V. Elsukov } 1545d8caf56eSAndrey V. Elsukov 1546