ipsec_output.c revision 117056
1112758Ssam/*- 2112758Ssam * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting 3112758Ssam * All rights reserved. 4112758Ssam * 5112758Ssam * Redistribution and use in source and binary forms, with or without 6112758Ssam * modification, are permitted provided that the following conditions 7112758Ssam * are met: 8112758Ssam * 1. Redistributions of source code must retain the above copyright 9112758Ssam * notice, this list of conditions and the following disclaimer. 10112758Ssam * 2. Redistributions in binary form must reproduce the above copyright 11112758Ssam * notice, this list of conditions and the following disclaimer in the 12112758Ssam * documentation and/or other materials provided with the distribution. 13112758Ssam * 14112758Ssam * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15112758Ssam * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16112758Ssam * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17112758Ssam * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18112758Ssam * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19112758Ssam * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20112758Ssam * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21112758Ssam * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22112758Ssam * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23112758Ssam * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24112758Ssam * SUCH DAMAGE. 25112758Ssam * 26112758Ssam * $FreeBSD: head/sys/netipsec/ipsec_output.c 117056 2003-06-30 05:05:19Z sam $ 27112758Ssam */ 28105197Ssam 29105197Ssam/* 30105197Ssam * IPsec output processing. 31105197Ssam */ 32105197Ssam#include "opt_inet.h" 33105197Ssam#include "opt_inet6.h" 34105197Ssam#include "opt_ipsec.h" 35105197Ssam 36105197Ssam#include <sys/param.h> 37105197Ssam#include <sys/systm.h> 38105197Ssam#include <sys/mbuf.h> 39105197Ssam#include <sys/domain.h> 40105197Ssam#include <sys/protosw.h> 41105197Ssam#include <sys/socket.h> 42105197Ssam#include <sys/errno.h> 43105197Ssam#include <sys/syslog.h> 44105197Ssam 45105197Ssam#include <net/if.h> 46105197Ssam#include <net/route.h> 47105197Ssam 48105197Ssam#include <netinet/in.h> 49105197Ssam#include <netinet/in_systm.h> 50105197Ssam#include <netinet/ip.h> 51105197Ssam#include <netinet/ip_var.h> 52105197Ssam#include <netinet/in_var.h> 53105197Ssam#include <netinet/ip_ecn.h> 54105197Ssam#ifdef INET6 55105197Ssam#include <netinet6/ip6_ecn.h> 56105197Ssam#endif 57105197Ssam 58105197Ssam#include <netinet/ip6.h> 59105197Ssam#ifdef INET6 60105197Ssam#include <netinet6/ip6_var.h> 61105197Ssam#endif 62105197Ssam#include <netinet/in_pcb.h> 63105197Ssam#ifdef INET6 64105197Ssam#include <netinet/icmp6.h> 65105197Ssam#endif 66105197Ssam 67105197Ssam#include <netipsec/ipsec.h> 68105197Ssam#ifdef INET6 69105197Ssam#include <netipsec/ipsec6.h> 70105197Ssam#endif 71105197Ssam#include <netipsec/ah_var.h> 72105197Ssam#include <netipsec/esp_var.h> 73105197Ssam#include <netipsec/ipcomp_var.h> 74105197Ssam 75105197Ssam#include <netipsec/xform.h> 76105197Ssam 77105197Ssam#include <netipsec/key.h> 78105197Ssam#include <netipsec/keydb.h> 79105197Ssam#include <netipsec/key_debug.h> 80105197Ssam 81105197Ssam#include <machine/in_cksum.h> 82105197Ssam 83105197Ssamint 84105197Ssamipsec_process_done(struct mbuf *m, struct ipsecrequest *isr) 85105197Ssam{ 86105197Ssam struct tdb_ident *tdbi; 87105197Ssam struct m_tag *mtag; 88105197Ssam struct secasvar *sav; 89105197Ssam struct secasindex *saidx; 90105197Ssam int error; 91105197Ssam 92105197Ssam#if 0 93105197Ssam SPLASSERT(net, "ipsec_process_done"); 94105197Ssam#endif 95105197Ssam 96105197Ssam KASSERT(m != NULL, ("ipsec_process_done: null mbuf")); 97105197Ssam KASSERT(isr != NULL, ("ipsec_process_done: null ISR")); 98105197Ssam sav = isr->sav; 99105197Ssam KASSERT(sav != NULL, ("ipsec_process_done: null SA")); 100105197Ssam KASSERT(sav->sah != NULL, ("ipsec_process_done: null SAH")); 101105197Ssam 102105197Ssam saidx = &sav->sah->saidx; 103105197Ssam switch (saidx->dst.sa.sa_family) { 104105197Ssam#ifdef INET 105105197Ssam case AF_INET: 106105197Ssam /* Fix the header length, for AH processing. */ 107105197Ssam mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 108105197Ssam break; 109105197Ssam#endif /* INET */ 110105197Ssam#ifdef INET6 111105197Ssam case AF_INET6: 112105197Ssam /* Fix the header length, for AH processing. */ 113105197Ssam if (m->m_pkthdr.len < sizeof (struct ip6_hdr)) { 114105197Ssam error = ENXIO; 115105197Ssam goto bad; 116105197Ssam } 117105197Ssam if (m->m_pkthdr.len - sizeof (struct ip6_hdr) > IPV6_MAXPACKET) { 118105197Ssam /* No jumbogram support. */ 119105197Ssam error = ENXIO; /*?*/ 120105197Ssam goto bad; 121105197Ssam } 122105197Ssam mtod(m, struct ip6_hdr *)->ip6_plen = 123105197Ssam htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 124105197Ssam break; 125105197Ssam#endif /* INET6 */ 126105197Ssam default: 127105197Ssam DPRINTF(("ipsec_process_done: unknown protocol family %u\n", 128105197Ssam saidx->dst.sa.sa_family)); 129105197Ssam error = ENXIO; 130105197Ssam goto bad; 131105197Ssam } 132105197Ssam 133105197Ssam /* 134105197Ssam * Add a record of what we've done or what needs to be done to the 135105197Ssam * packet. 136105197Ssam */ 137105197Ssam mtag = m_tag_get(PACKET_TAG_IPSEC_OUT_DONE, 138105197Ssam sizeof(struct tdb_ident), M_NOWAIT); 139105197Ssam if (mtag == NULL) { 140105197Ssam DPRINTF(("ipsec_process_done: could not get packet tag\n")); 141105197Ssam error = ENOMEM; 142105197Ssam goto bad; 143105197Ssam } 144105197Ssam 145105197Ssam tdbi = (struct tdb_ident *)(mtag + 1); 146105197Ssam tdbi->dst = saidx->dst; 147105197Ssam tdbi->proto = saidx->proto; 148105197Ssam tdbi->spi = sav->spi; 149105197Ssam m_tag_prepend(m, mtag); 150105197Ssam 151105197Ssam /* 152105197Ssam * If there's another (bundled) SA to apply, do so. 153105197Ssam * Note that this puts a burden on the kernel stack size. 154105197Ssam * If this is a problem we'll need to introduce a queue 155105197Ssam * to set the packet on so we can unwind the stack before 156105197Ssam * doing further processing. 157105197Ssam */ 158105197Ssam if (isr->next) { 159105197Ssam newipsecstat.ips_out_bundlesa++; 160105197Ssam return ipsec4_process_packet(m, isr->next, 0, 0); 161105197Ssam } 162117056Ssam key_sa_recordxfer(sav, m); /* record data transfer */ 163105197Ssam 164105197Ssam /* 165105197Ssam * We're done with IPsec processing, transmit the packet using the 166105197Ssam * appropriate network protocol (IP or IPv6). SPD lookup will be 167105197Ssam * performed again there. 168105197Ssam */ 169105197Ssam switch (saidx->dst.sa.sa_family) { 170105197Ssam#ifdef INET 171105197Ssam struct ip *ip; 172105197Ssam case AF_INET: 173105197Ssam ip = mtod(m, struct ip *); 174105197Ssam ip->ip_len = ntohs(ip->ip_len); 175105197Ssam ip->ip_off = ntohs(ip->ip_off); 176105197Ssam 177105197Ssam return ip_output(m, NULL, NULL, IP_RAWOUTPUT, NULL, NULL); 178105197Ssam#endif /* INET */ 179105197Ssam#ifdef INET6 180105197Ssam case AF_INET6: 181105197Ssam /* 182105197Ssam * We don't need massage, IPv6 header fields are always in 183105197Ssam * net endian. 184105197Ssam */ 185105197Ssam return ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 186105197Ssam#endif /* INET6 */ 187105197Ssam } 188105197Ssam panic("ipsec_process_done"); 189105197Ssambad: 190105197Ssam m_freem(m); 191105197Ssam KEY_FREESAV(&sav); 192105197Ssam return (error); 193105197Ssam} 194105197Ssam 195105197Ssamstatic struct ipsecrequest * 196105197Ssamipsec_nextisr( 197105197Ssam struct mbuf *m, 198105197Ssam struct ipsecrequest *isr, 199105197Ssam int af, 200105197Ssam struct secasindex *saidx, 201105197Ssam int *error 202105197Ssam) 203105197Ssam{ 204105197Ssam#define IPSEC_OSTAT(x,y,z) (isr->saidx.proto == IPPROTO_ESP ? (x)++ : \ 205105197Ssam isr->saidx.proto == IPPROTO_AH ? (y)++ : (z)++) 206105197Ssam struct secasvar *sav; 207105197Ssam 208105197Ssam#if 0 209105197Ssam SPLASSERT(net, "ipsec_nextisr"); 210105197Ssam#endif 211105197Ssam KASSERT(af == AF_INET || af == AF_INET6, 212105197Ssam ("ipsec_nextisr: invalid address family %u", af)); 213105197Ssamagain: 214105197Ssam /* 215105197Ssam * Craft SA index to search for proper SA. Note that 216105197Ssam * we only fillin unspecified SA peers for transport 217105197Ssam * mode; for tunnel mode they must already be filled in. 218105197Ssam */ 219105197Ssam *saidx = isr->saidx; 220105197Ssam if (isr->saidx.mode == IPSEC_MODE_TRANSPORT) { 221105197Ssam /* Fillin unspecified SA peers only for transport mode */ 222105197Ssam if (af == AF_INET) { 223105197Ssam struct sockaddr_in *sin; 224105197Ssam struct ip *ip = mtod(m, struct ip *); 225105197Ssam 226105197Ssam if (saidx->src.sa.sa_len == 0) { 227105197Ssam sin = &saidx->src.sin; 228105197Ssam sin->sin_len = sizeof(*sin); 229105197Ssam sin->sin_family = AF_INET; 230105197Ssam sin->sin_port = IPSEC_PORT_ANY; 231105197Ssam sin->sin_addr = ip->ip_src; 232105197Ssam } 233105197Ssam if (saidx->dst.sa.sa_len == 0) { 234105197Ssam sin = &saidx->dst.sin; 235105197Ssam sin->sin_len = sizeof(*sin); 236105197Ssam sin->sin_family = AF_INET; 237105197Ssam sin->sin_port = IPSEC_PORT_ANY; 238105197Ssam sin->sin_addr = ip->ip_dst; 239105197Ssam } 240105197Ssam } else { 241105197Ssam struct sockaddr_in6 *sin6; 242105197Ssam struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 243105197Ssam 244105197Ssam if (saidx->src.sin6.sin6_len == 0) { 245105197Ssam sin6 = (struct sockaddr_in6 *)&saidx->src; 246105197Ssam sin6->sin6_len = sizeof(*sin6); 247105197Ssam sin6->sin6_family = AF_INET6; 248105197Ssam sin6->sin6_port = IPSEC_PORT_ANY; 249105197Ssam sin6->sin6_addr = ip6->ip6_src; 250105197Ssam if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) { 251105197Ssam /* fix scope id for comparing SPD */ 252105197Ssam sin6->sin6_addr.s6_addr16[1] = 0; 253105197Ssam sin6->sin6_scope_id = 254105197Ssam ntohs(ip6->ip6_src.s6_addr16[1]); 255105197Ssam } 256105197Ssam } 257105197Ssam if (saidx->dst.sin6.sin6_len == 0) { 258105197Ssam sin6 = (struct sockaddr_in6 *)&saidx->dst; 259105197Ssam sin6->sin6_len = sizeof(*sin6); 260105197Ssam sin6->sin6_family = AF_INET6; 261105197Ssam sin6->sin6_port = IPSEC_PORT_ANY; 262105197Ssam sin6->sin6_addr = ip6->ip6_dst; 263105197Ssam if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 264105197Ssam /* fix scope id for comparing SPD */ 265105197Ssam sin6->sin6_addr.s6_addr16[1] = 0; 266105197Ssam sin6->sin6_scope_id = 267105197Ssam ntohs(ip6->ip6_dst.s6_addr16[1]); 268105197Ssam } 269105197Ssam } 270105197Ssam } 271105197Ssam } 272105197Ssam 273105197Ssam /* 274105197Ssam * Lookup SA and validate it. 275105197Ssam */ 276105197Ssam *error = key_checkrequest(isr, saidx); 277105197Ssam if (*error != 0) { 278105197Ssam /* 279105197Ssam * IPsec processing is required, but no SA found. 280105197Ssam * I assume that key_acquire() had been called 281105197Ssam * to get/establish the SA. Here I discard 282105197Ssam * this packet because it is responsibility for 283105197Ssam * upper layer to retransmit the packet. 284105197Ssam */ 285105197Ssam newipsecstat.ips_out_nosa++; 286105197Ssam goto bad; 287105197Ssam } 288105197Ssam sav = isr->sav; 289105197Ssam if (sav == NULL) { /* XXX valid return */ 290105197Ssam KASSERT(ipsec_get_reqlevel(isr) == IPSEC_LEVEL_USE, 291105197Ssam ("ipsec_nextisr: no SA found, but required; level %u", 292105197Ssam ipsec_get_reqlevel(isr))); 293105197Ssam isr = isr->next; 294105197Ssam if (isr == NULL) { 295105197Ssam /*XXXstatistic??*/ 296105197Ssam *error = EINVAL; /*XXX*/ 297105197Ssam return isr; 298105197Ssam } 299105197Ssam goto again; 300105197Ssam } 301105197Ssam 302105197Ssam /* 303105197Ssam * Check system global policy controls. 304105197Ssam */ 305105197Ssam if ((isr->saidx.proto == IPPROTO_ESP && !esp_enable) || 306105197Ssam (isr->saidx.proto == IPPROTO_AH && !ah_enable) || 307105197Ssam (isr->saidx.proto == IPPROTO_IPCOMP && !ipcomp_enable)) { 308105197Ssam DPRINTF(("ipsec_nextisr: IPsec outbound packet dropped due" 309105197Ssam " to policy (check your sysctls)\n")); 310105197Ssam IPSEC_OSTAT(espstat.esps_pdrops, ahstat.ahs_pdrops, 311105197Ssam ipcompstat.ipcomps_pdrops); 312105197Ssam *error = EHOSTUNREACH; 313105197Ssam goto bad; 314105197Ssam } 315105197Ssam 316105197Ssam /* 317105197Ssam * Sanity check the SA contents for the caller 318105197Ssam * before they invoke the xform output method. 319105197Ssam */ 320105197Ssam if (sav->tdb_xform == NULL) { 321105197Ssam DPRINTF(("ipsec_nextisr: no transform for SA\n")); 322105197Ssam IPSEC_OSTAT(espstat.esps_noxform, ahstat.ahs_noxform, 323105197Ssam ipcompstat.ipcomps_noxform); 324105197Ssam *error = EHOSTUNREACH; 325105197Ssam goto bad; 326105197Ssam } 327105197Ssam return isr; 328105197Ssambad: 329105197Ssam KASSERT(*error != 0, ("ipsec_nextisr: error return w/ no error code")); 330105197Ssam return NULL; 331105197Ssam#undef IPSEC_OSTAT 332105197Ssam} 333105197Ssam 334105197Ssam#ifdef INET 335105197Ssam/* 336105197Ssam * IPsec output logic for IPv4. 337105197Ssam */ 338105197Ssamint 339105197Ssamipsec4_process_packet( 340105197Ssam struct mbuf *m, 341105197Ssam struct ipsecrequest *isr, 342105197Ssam int flags, 343105197Ssam int tunalready) 344105197Ssam{ 345105197Ssam struct secasindex saidx; 346105197Ssam struct secasvar *sav; 347105197Ssam struct ip *ip; 348105197Ssam int s, error, i, off; 349105197Ssam 350105197Ssam KASSERT(m != NULL, ("ipsec4_process_packet: null mbuf")); 351105197Ssam KASSERT(isr != NULL, ("ipsec4_process_packet: null isr")); 352105197Ssam 353105197Ssam s = splnet(); /* insure SA contents don't change */ 354105197Ssam 355105197Ssam isr = ipsec_nextisr(m, isr, AF_INET, &saidx, &error); 356105197Ssam if (isr == NULL) 357105197Ssam goto bad; 358105197Ssam 359105197Ssam sav = isr->sav; 360105197Ssam if (!tunalready) { 361105197Ssam union sockaddr_union *dst = &sav->sah->saidx.dst; 362105197Ssam int setdf; 363105197Ssam 364105197Ssam /* 365105197Ssam * Collect IP_DF state from the outer header. 366105197Ssam */ 367105197Ssam if (dst->sa.sa_family == AF_INET) { 368105197Ssam if (m->m_len < sizeof (struct ip) && 369105197Ssam (m = m_pullup(m, sizeof (struct ip))) == NULL) { 370105197Ssam error = ENOBUFS; 371105197Ssam goto bad; 372105197Ssam } 373105197Ssam ip = mtod(m, struct ip *); 374105197Ssam /* Honor system-wide control of how to handle IP_DF */ 375105197Ssam switch (ip4_ipsec_dfbit) { 376105197Ssam case 0: /* clear in outer header */ 377105197Ssam case 1: /* set in outer header */ 378105197Ssam setdf = ip4_ipsec_dfbit; 379105197Ssam break; 380105197Ssam default: /* propagate to outer header */ 381105197Ssam setdf = ntohs(ip->ip_off & IP_DF); 382105197Ssam break; 383105197Ssam } 384105197Ssam } else { 385105197Ssam ip = NULL; /* keep compiler happy */ 386105197Ssam setdf = 0; 387105197Ssam } 388105197Ssam /* Do the appropriate encapsulation, if necessary */ 389105197Ssam if (isr->saidx.mode == IPSEC_MODE_TUNNEL || /* Tunnel requ'd */ 390105197Ssam dst->sa.sa_family != AF_INET || /* PF mismatch */ 391105197Ssam#if 0 392105197Ssam (sav->flags & SADB_X_SAFLAGS_TUNNEL) || /* Tunnel requ'd */ 393105197Ssam sav->tdb_xform->xf_type == XF_IP4 || /* ditto */ 394105197Ssam#endif 395105197Ssam (dst->sa.sa_family == AF_INET && /* Proxy */ 396105197Ssam dst->sin.sin_addr.s_addr != INADDR_ANY && 397105197Ssam dst->sin.sin_addr.s_addr != ip->ip_dst.s_addr)) { 398105197Ssam struct mbuf *mp; 399105197Ssam 400105197Ssam /* Fix IPv4 header checksum and length */ 401105197Ssam if (m->m_len < sizeof (struct ip) && 402105197Ssam (m = m_pullup(m, sizeof (struct ip))) == NULL) { 403105197Ssam error = ENOBUFS; 404105197Ssam goto bad; 405105197Ssam } 406105197Ssam ip = mtod(m, struct ip *); 407105197Ssam ip->ip_len = htons(m->m_pkthdr.len); 408105197Ssam ip->ip_sum = 0; 409105197Ssam#ifdef _IP_VHL 410105197Ssam if (ip->ip_vhl == IP_VHL_BORING) 411105197Ssam ip->ip_sum = in_cksum_hdr(ip); 412105197Ssam else 413105197Ssam ip->ip_sum = in_cksum(m, 414105197Ssam _IP_VHL_HL(ip->ip_vhl) << 2); 415105197Ssam#else 416105197Ssam ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 417105197Ssam#endif 418105197Ssam 419105197Ssam /* Encapsulate the packet */ 420105197Ssam error = ipip_output(m, isr, &mp, 0, 0); 421105197Ssam if (mp == NULL && !error) { 422105197Ssam /* Should never happen. */ 423105197Ssam DPRINTF(("ipsec4_process_packet: ipip_output " 424105197Ssam "returns no mbuf and no error!")); 425105197Ssam error = EFAULT; 426105197Ssam } 427105197Ssam if (error) { 428105197Ssam if (mp) 429105197Ssam m_freem(mp); 430105197Ssam goto bad; 431105197Ssam } 432105197Ssam m = mp, mp = NULL; 433105197Ssam /* 434105197Ssam * ipip_output clears IP_DF in the new header. If 435105197Ssam * we need to propagate IP_DF from the outer header, 436105197Ssam * then we have to do it here. 437105197Ssam * 438105197Ssam * XXX shouldn't assume what ipip_output does. 439105197Ssam */ 440105197Ssam if (dst->sa.sa_family == AF_INET && setdf) { 441105197Ssam if (m->m_len < sizeof (struct ip) && 442105197Ssam (m = m_pullup(m, sizeof (struct ip))) == NULL) { 443105197Ssam error = ENOBUFS; 444105197Ssam goto bad; 445105197Ssam } 446105197Ssam ip = mtod(m, struct ip *); 447105197Ssam ip->ip_off = ntohs(ip->ip_off); 448105197Ssam ip->ip_off |= IP_DF; 449105197Ssam ip->ip_off = htons(ip->ip_off); 450105197Ssam } 451105197Ssam } 452105197Ssam } 453105197Ssam 454105197Ssam /* 455105197Ssam * Dispatch to the appropriate IPsec transform logic. The 456105197Ssam * packet will be returned for transmission after crypto 457105197Ssam * processing, etc. are completed. For encapsulation we 458105197Ssam * bypass this call because of the explicit call done above 459105197Ssam * (necessary to deal with IP_DF handling for IPv4). 460105197Ssam * 461105197Ssam * NB: m & sav are ``passed to caller'' who's reponsible for 462105197Ssam * for reclaiming their resources. 463105197Ssam */ 464105197Ssam if (sav->tdb_xform->xf_type != XF_IP4) { 465105197Ssam ip = mtod(m, struct ip *); 466105197Ssam i = ip->ip_hl << 2; 467105197Ssam off = offsetof(struct ip, ip_p); 468105197Ssam error = (*sav->tdb_xform->xf_output)(m, isr, NULL, i, off); 469105197Ssam } else { 470105197Ssam error = ipsec_process_done(m, isr); 471105197Ssam } 472105197Ssam splx(s); 473105197Ssam return error; 474105197Ssambad: 475105197Ssam splx(s); 476105197Ssam if (m) 477105197Ssam m_freem(m); 478105197Ssam return error; 479105197Ssam} 480105197Ssam#endif 481105197Ssam 482105197Ssam#ifdef INET6 483105197Ssam/* 484105197Ssam * Chop IP6 header from the payload. 485105197Ssam */ 486105197Ssamstatic struct mbuf * 487105197Ssamipsec6_splithdr(struct mbuf *m) 488105197Ssam{ 489105197Ssam struct mbuf *mh; 490105197Ssam struct ip6_hdr *ip6; 491105197Ssam int hlen; 492105197Ssam 493105197Ssam KASSERT(m->m_len >= sizeof (struct ip6_hdr), 494105197Ssam ("ipsec6_splithdr: first mbuf too short, len %u", m->m_len)); 495105197Ssam ip6 = mtod(m, struct ip6_hdr *); 496105197Ssam hlen = sizeof(struct ip6_hdr); 497105197Ssam if (m->m_len > hlen) { 498111119Simp MGETHDR(mh, M_DONTWAIT, MT_HEADER); 499105197Ssam if (!mh) { 500105197Ssam m_freem(m); 501105197Ssam return NULL; 502105197Ssam } 503108466Ssam M_MOVE_PKTHDR(mh, m); 504105197Ssam MH_ALIGN(mh, hlen); 505105197Ssam m->m_len -= hlen; 506105197Ssam m->m_data += hlen; 507105197Ssam mh->m_next = m; 508105197Ssam m = mh; 509105197Ssam m->m_len = hlen; 510105197Ssam bcopy((caddr_t)ip6, mtod(m, caddr_t), hlen); 511105197Ssam } else if (m->m_len < hlen) { 512105197Ssam m = m_pullup(m, hlen); 513105197Ssam if (!m) 514105197Ssam return NULL; 515105197Ssam } 516105197Ssam return m; 517105197Ssam} 518105197Ssam 519105197Ssam/* 520105197Ssam * IPsec output logic for IPv6, transport mode. 521105197Ssam */ 522105197Ssamint 523105197Ssamipsec6_output_trans( 524105197Ssam struct ipsec_output_state *state, 525105197Ssam u_char *nexthdrp, 526105197Ssam struct mbuf *mprev, 527105197Ssam struct secpolicy *sp, 528105197Ssam int flags, 529105197Ssam int *tun) 530105197Ssam{ 531105197Ssam struct ipsecrequest *isr; 532105197Ssam struct secasindex saidx; 533105197Ssam int error = 0; 534105197Ssam struct mbuf *m; 535105197Ssam 536105197Ssam KASSERT(state != NULL, ("ipsec6_output: null state")); 537105197Ssam KASSERT(state->m != NULL, ("ipsec6_output: null m")); 538105197Ssam KASSERT(nexthdrp != NULL, ("ipsec6_output: null nexthdrp")); 539105197Ssam KASSERT(mprev != NULL, ("ipsec6_output: null mprev")); 540105197Ssam KASSERT(sp != NULL, ("ipsec6_output: null sp")); 541105197Ssam KASSERT(tun != NULL, ("ipsec6_output: null tun")); 542105197Ssam 543105197Ssam KEYDEBUG(KEYDEBUG_IPSEC_DATA, 544105197Ssam printf("ipsec6_output_trans: applyed SP\n"); 545105197Ssam kdebug_secpolicy(sp)); 546105197Ssam 547105197Ssam isr = sp->req; 548105197Ssam if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 549105197Ssam /* the rest will be handled by ipsec6_output_tunnel() */ 550105197Ssam *tun = 1; /* need tunnel-mode processing */ 551105197Ssam return 0; 552105197Ssam } 553105197Ssam 554105197Ssam *tun = 0; 555105197Ssam m = state->m; 556105197Ssam 557105197Ssam isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 558105197Ssam if (isr == NULL) { 559105197Ssam#ifdef notdef 560105197Ssam /* XXX should notification be done for all errors ? */ 561105197Ssam /* 562105197Ssam * Notify the fact that the packet is discarded 563105197Ssam * to ourselves. I believe this is better than 564105197Ssam * just silently discarding. (jinmei@kame.net) 565105197Ssam * XXX: should we restrict the error to TCP packets? 566105197Ssam * XXX: should we directly notify sockets via 567105197Ssam * pfctlinputs? 568105197Ssam */ 569105197Ssam icmp6_error(m, ICMP6_DST_UNREACH, 570105197Ssam ICMP6_DST_UNREACH_ADMIN, 0); 571105197Ssam m = NULL; /* NB: icmp6_error frees mbuf */ 572105197Ssam#endif 573105197Ssam goto bad; 574105197Ssam } 575105197Ssam 576105197Ssam return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 577105197Ssam sizeof (struct ip6_hdr), 578105197Ssam offsetof(struct ip6_hdr, ip6_nxt)); 579105197Ssambad: 580105197Ssam if (m) 581105197Ssam m_freem(m); 582105197Ssam state->m = NULL; 583105197Ssam return error; 584105197Ssam} 585105197Ssam 586105197Ssamstatic int 587105197Ssamipsec6_encapsulate(struct mbuf *m, struct secasvar *sav) 588105197Ssam{ 589105197Ssam struct ip6_hdr *oip6; 590105197Ssam struct ip6_hdr *ip6; 591105197Ssam size_t plen; 592105197Ssam 593105197Ssam /* can't tunnel between different AFs */ 594105197Ssam if (sav->sah->saidx.src.sa.sa_family != AF_INET6 || 595105197Ssam sav->sah->saidx.dst.sa.sa_family != AF_INET6) { 596105197Ssam m_freem(m); 597105197Ssam return EINVAL; 598105197Ssam } 599105197Ssam KASSERT(m->m_len != sizeof (struct ip6_hdr), 600105197Ssam ("ipsec6_encapsulate: mbuf wrong size; len %u", m->m_len)); 601105197Ssam 602105197Ssam 603105197Ssam /* 604105197Ssam * grow the mbuf to accomodate the new IPv6 header. 605105197Ssam */ 606105197Ssam plen = m->m_pkthdr.len; 607105197Ssam if (M_LEADINGSPACE(m->m_next) < sizeof(struct ip6_hdr)) { 608105197Ssam struct mbuf *n; 609111119Simp MGET(n, M_DONTWAIT, MT_DATA); 610105197Ssam if (!n) { 611105197Ssam m_freem(m); 612105197Ssam return ENOBUFS; 613105197Ssam } 614105197Ssam n->m_len = sizeof(struct ip6_hdr); 615105197Ssam n->m_next = m->m_next; 616105197Ssam m->m_next = n; 617105197Ssam m->m_pkthdr.len += sizeof(struct ip6_hdr); 618105197Ssam oip6 = mtod(n, struct ip6_hdr *); 619105197Ssam } else { 620105197Ssam m->m_next->m_len += sizeof(struct ip6_hdr); 621105197Ssam m->m_next->m_data -= sizeof(struct ip6_hdr); 622105197Ssam m->m_pkthdr.len += sizeof(struct ip6_hdr); 623105197Ssam oip6 = mtod(m->m_next, struct ip6_hdr *); 624105197Ssam } 625105197Ssam ip6 = mtod(m, struct ip6_hdr *); 626113076Sdes bcopy((caddr_t)ip6, (caddr_t)oip6, sizeof(struct ip6_hdr)); 627105197Ssam 628105197Ssam /* Fake link-local scope-class addresses */ 629105197Ssam if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 630105197Ssam oip6->ip6_src.s6_addr16[1] = 0; 631105197Ssam if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 632105197Ssam oip6->ip6_dst.s6_addr16[1] = 0; 633105197Ssam 634105197Ssam /* construct new IPv6 header. see RFC 2401 5.1.2.2 */ 635105197Ssam /* ECN consideration. */ 636105197Ssam ip6_ecn_ingress(ip6_ipsec_ecn, &ip6->ip6_flow, &oip6->ip6_flow); 637105197Ssam if (plen < IPV6_MAXPACKET - sizeof(struct ip6_hdr)) 638105197Ssam ip6->ip6_plen = htons(plen); 639105197Ssam else { 640105197Ssam /* ip6->ip6_plen will be updated in ip6_output() */ 641105197Ssam } 642105197Ssam ip6->ip6_nxt = IPPROTO_IPV6; 643105197Ssam sav->sah->saidx.src.sin6.sin6_addr = ip6->ip6_src; 644105197Ssam sav->sah->saidx.dst.sin6.sin6_addr = ip6->ip6_dst; 645105197Ssam ip6->ip6_hlim = IPV6_DEFHLIM; 646105197Ssam 647105197Ssam /* XXX Should ip6_src be updated later ? */ 648105197Ssam 649105197Ssam return 0; 650105197Ssam} 651105197Ssam 652105197Ssam/* 653105197Ssam * IPsec output logic for IPv6, tunnel mode. 654105197Ssam */ 655105197Ssamint 656105197Ssamipsec6_output_tunnel(struct ipsec_output_state *state, struct secpolicy *sp, int flags) 657105197Ssam{ 658105197Ssam struct ip6_hdr *ip6; 659105197Ssam struct ipsecrequest *isr; 660105197Ssam struct secasindex saidx; 661105197Ssam int error; 662105197Ssam struct sockaddr_in6* dst6; 663105197Ssam struct mbuf *m; 664105197Ssam 665105197Ssam KASSERT(state != NULL, ("ipsec6_output: null state")); 666105197Ssam KASSERT(state->m != NULL, ("ipsec6_output: null m")); 667105197Ssam KASSERT(sp != NULL, ("ipsec6_output: null sp")); 668105197Ssam 669105197Ssam KEYDEBUG(KEYDEBUG_IPSEC_DATA, 670105197Ssam printf("ipsec6_output_tunnel: applyed SP\n"); 671105197Ssam kdebug_secpolicy(sp)); 672105197Ssam 673105197Ssam m = state->m; 674105197Ssam /* 675105197Ssam * transport mode ipsec (before the 1st tunnel mode) is already 676105197Ssam * processed by ipsec6_output_trans(). 677105197Ssam */ 678105197Ssam for (isr = sp->req; isr; isr = isr->next) { 679105197Ssam if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 680105197Ssam break; 681105197Ssam } 682105197Ssam isr = ipsec_nextisr(m, isr, AF_INET6, &saidx, &error); 683105197Ssam if (isr == NULL) 684105197Ssam goto bad; 685105197Ssam 686105197Ssam /* 687105197Ssam * There may be the case that SA status will be changed when 688105197Ssam * we are refering to one. So calling splsoftnet(). 689105197Ssam */ 690105197Ssam if (isr->saidx.mode == IPSEC_MODE_TUNNEL) { 691105197Ssam /* 692105197Ssam * build IPsec tunnel. 693105197Ssam */ 694105197Ssam /* XXX should be processed with other familiy */ 695105197Ssam if (isr->sav->sah->saidx.src.sa.sa_family != AF_INET6) { 696105197Ssam ipseclog((LOG_ERR, "ipsec6_output_tunnel: " 697105197Ssam "family mismatched between inner and outer, spi=%u\n", 698105197Ssam ntohl(isr->sav->spi))); 699105197Ssam newipsecstat.ips_out_inval++; 700105197Ssam error = EAFNOSUPPORT; 701105197Ssam goto bad; 702105197Ssam } 703105197Ssam 704105197Ssam m = ipsec6_splithdr(m); 705105197Ssam if (!m) { 706105197Ssam newipsecstat.ips_out_nomem++; 707105197Ssam error = ENOMEM; 708105197Ssam goto bad; 709105197Ssam } 710105197Ssam error = ipsec6_encapsulate(m, isr->sav); 711105197Ssam if (error) { 712105197Ssam m = NULL; 713105197Ssam goto bad; 714105197Ssam } 715105197Ssam ip6 = mtod(m, struct ip6_hdr *); 716105197Ssam 717105197Ssam state->ro = &isr->sav->sah->sa_route; 718105197Ssam state->dst = (struct sockaddr *)&state->ro->ro_dst; 719105197Ssam dst6 = (struct sockaddr_in6 *)state->dst; 720105197Ssam if (state->ro->ro_rt 721105197Ssam && ((state->ro->ro_rt->rt_flags & RTF_UP) == 0 722105197Ssam || !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &ip6->ip6_dst))) { 723105197Ssam RTFREE(state->ro->ro_rt); 724105197Ssam state->ro->ro_rt = NULL; 725105197Ssam } 726105197Ssam if (state->ro->ro_rt == 0) { 727105197Ssam bzero(dst6, sizeof(*dst6)); 728105197Ssam dst6->sin6_family = AF_INET6; 729105197Ssam dst6->sin6_len = sizeof(*dst6); 730105197Ssam dst6->sin6_addr = ip6->ip6_dst; 731105197Ssam rtalloc(state->ro); 732105197Ssam } 733105197Ssam if (state->ro->ro_rt == 0) { 734105197Ssam ip6stat.ip6s_noroute++; 735105197Ssam newipsecstat.ips_out_noroute++; 736105197Ssam error = EHOSTUNREACH; 737105197Ssam goto bad; 738105197Ssam } 739105197Ssam 740105197Ssam /* adjust state->dst if tunnel endpoint is offlink */ 741105197Ssam if (state->ro->ro_rt->rt_flags & RTF_GATEWAY) { 742105197Ssam state->dst = (struct sockaddr *)state->ro->ro_rt->rt_gateway; 743105197Ssam dst6 = (struct sockaddr_in6 *)state->dst; 744105197Ssam } 745105197Ssam } 746105197Ssam 747105197Ssam m = ipsec6_splithdr(m); 748105197Ssam if (!m) { 749105197Ssam newipsecstat.ips_out_nomem++; 750105197Ssam error = ENOMEM; 751105197Ssam goto bad; 752105197Ssam } 753105197Ssam ip6 = mtod(m, struct ip6_hdr *); 754105197Ssam return (*isr->sav->tdb_xform->xf_output)(m, isr, NULL, 755105197Ssam sizeof (struct ip6_hdr), 756105197Ssam offsetof(struct ip6_hdr, ip6_nxt)); 757105197Ssambad: 758105197Ssam if (m) 759105197Ssam m_freem(m); 760105197Ssam state->m = NULL; 761105197Ssam return error; 762105197Ssam} 763105197Ssam#endif /*INET6*/ 764