ipsec_input.c revision 159965
1105197Ssam/* $FreeBSD: head/sys/netipsec/ipsec_input.c 159965 2006-06-26 22:30:08Z thompsa $ */ 2112758Ssam/* $OpenBSD: ipsec_input.c,v 1.63 2003/02/20 18:35:43 deraadt Exp $ */ 3139823Simp/*- 4112758Ssam * The authors of this code are John Ioannidis (ji@tla.org), 5112758Ssam * Angelos D. Keromytis (kermit@csd.uch.gr) and 6112758Ssam * Niels Provos (provos@physnet.uni-hamburg.de). 7112758Ssam * 8112758Ssam * This code was written by John Ioannidis for BSD/OS in Athens, Greece, 9112758Ssam * in November 1995. 10112758Ssam * 11112758Ssam * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996, 12112758Ssam * by Angelos D. Keromytis. 13112758Ssam * 14112758Ssam * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis 15112758Ssam * and Niels Provos. 16112758Ssam * 17112758Ssam * Additional features in 1999 by Angelos D. Keromytis. 18112758Ssam * 19112758Ssam * Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis, 20112758Ssam * Angelos D. Keromytis and Niels Provos. 21112758Ssam * Copyright (c) 2001, Angelos D. Keromytis. 22112758Ssam * 23112758Ssam * Permission to use, copy, and modify this software with or without fee 24112758Ssam * is hereby granted, provided that this entire notice is included in 25112758Ssam * all copies of any software which is or includes a copy or 26112758Ssam * modification of this software. 27112758Ssam * You may use this code under the GNU public license if you so wish. Please 28112758Ssam * contribute changes back to the authors under this freer than GPL license 29112758Ssam * so that we may further the use of strong encryption without limitations to 30112758Ssam * all. 31112758Ssam * 32112758Ssam * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR 33112758Ssam * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY 34112758Ssam * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE 35112758Ssam * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR 36112758Ssam * PURPOSE. 37112758Ssam */ 38105197Ssam 39105197Ssam/* 40105197Ssam * IPsec input processing. 41105197Ssam */ 42105197Ssam 43105197Ssam#include "opt_inet.h" 44105197Ssam#include "opt_inet6.h" 45105197Ssam#include "opt_ipsec.h" 46159965Sthompsa#include "opt_enc.h" 47105197Ssam 48105197Ssam#include <sys/param.h> 49105197Ssam#include <sys/systm.h> 50105197Ssam#include <sys/malloc.h> 51105197Ssam#include <sys/mbuf.h> 52105197Ssam#include <sys/domain.h> 53105197Ssam#include <sys/protosw.h> 54105197Ssam#include <sys/socket.h> 55105197Ssam#include <sys/errno.h> 56105197Ssam#include <sys/syslog.h> 57105197Ssam 58105197Ssam#include <net/if.h> 59105197Ssam#include <net/route.h> 60105197Ssam#include <net/netisr.h> 61105197Ssam 62105197Ssam#include <netinet/in.h> 63105197Ssam#include <netinet/in_systm.h> 64105197Ssam#include <netinet/ip.h> 65105197Ssam#include <netinet/ip_var.h> 66105197Ssam#include <netinet/in_var.h> 67105197Ssam 68105197Ssam#include <netinet/ip6.h> 69105197Ssam#ifdef INET6 70105197Ssam#include <netinet6/ip6_var.h> 71105197Ssam#endif 72105197Ssam#include <netinet/in_pcb.h> 73105197Ssam#ifdef INET6 74105197Ssam#include <netinet/icmp6.h> 75105197Ssam#endif 76105197Ssam 77105197Ssam#include <netipsec/ipsec.h> 78105197Ssam#ifdef INET6 79105197Ssam#include <netipsec/ipsec6.h> 80105197Ssam#endif 81105197Ssam#include <netipsec/ah_var.h> 82105197Ssam#include <netipsec/esp.h> 83105197Ssam#include <netipsec/esp_var.h> 84105197Ssam#include <netipsec/ipcomp_var.h> 85105197Ssam 86105197Ssam#include <netipsec/key.h> 87105197Ssam#include <netipsec/keydb.h> 88105197Ssam 89105197Ssam#include <netipsec/xform.h> 90105197Ssam#include <netinet6/ip6protosw.h> 91105197Ssam 92105197Ssam#include <machine/in_cksum.h> 93105197Ssam#include <machine/stdarg.h> 94105197Ssam 95105197Ssam#define IPSEC_ISTAT(p,x,y,z) ((p) == IPPROTO_ESP ? (x)++ : \ 96105197Ssam (p) == IPPROTO_AH ? (y)++ : (z)++) 97105197Ssam 98120585Ssamstatic void ipsec4_common_ctlinput(int, struct sockaddr *, void *, int); 99120585Ssam 100105197Ssam/* 101105197Ssam * ipsec_common_input gets called when an IPsec-protected packet 102105197Ssam * is received by IPv4 or IPv6. It's job is to find the right SA 103105197Ssam # and call the appropriate transform. The transform callback 104105197Ssam * takes care of further processing (like ingress filtering). 105105197Ssam */ 106105197Ssamstatic int 107105197Ssamipsec_common_input(struct mbuf *m, int skip, int protoff, int af, int sproto) 108105197Ssam{ 109105197Ssam union sockaddr_union dst_address; 110105197Ssam struct secasvar *sav; 111105197Ssam u_int32_t spi; 112119643Ssam int error; 113105197Ssam 114105197Ssam IPSEC_ISTAT(sproto, espstat.esps_input, ahstat.ahs_input, 115105197Ssam ipcompstat.ipcomps_input); 116105197Ssam 117120585Ssam IPSEC_ASSERT(m != NULL, ("null packet")); 118105197Ssam 119105197Ssam if ((sproto == IPPROTO_ESP && !esp_enable) || 120105197Ssam (sproto == IPPROTO_AH && !ah_enable) || 121105197Ssam (sproto == IPPROTO_IPCOMP && !ipcomp_enable)) { 122105197Ssam m_freem(m); 123105197Ssam IPSEC_ISTAT(sproto, espstat.esps_pdrops, ahstat.ahs_pdrops, 124105197Ssam ipcompstat.ipcomps_pdrops); 125105197Ssam return EOPNOTSUPP; 126105197Ssam } 127105197Ssam 128105197Ssam if (m->m_pkthdr.len - skip < 2 * sizeof (u_int32_t)) { 129105197Ssam m_freem(m); 130105197Ssam IPSEC_ISTAT(sproto, espstat.esps_hdrops, ahstat.ahs_hdrops, 131105197Ssam ipcompstat.ipcomps_hdrops); 132120585Ssam DPRINTF(("%s: packet too small\n", __func__)); 133105197Ssam return EINVAL; 134105197Ssam } 135105197Ssam 136105197Ssam /* Retrieve the SPI from the relevant IPsec header */ 137105197Ssam if (sproto == IPPROTO_ESP) 138105197Ssam m_copydata(m, skip, sizeof(u_int32_t), (caddr_t) &spi); 139105197Ssam else if (sproto == IPPROTO_AH) 140105197Ssam m_copydata(m, skip + sizeof(u_int32_t), sizeof(u_int32_t), 141105197Ssam (caddr_t) &spi); 142105197Ssam else if (sproto == IPPROTO_IPCOMP) { 143105197Ssam u_int16_t cpi; 144105197Ssam m_copydata(m, skip + sizeof(u_int16_t), sizeof(u_int16_t), 145105197Ssam (caddr_t) &cpi); 146105197Ssam spi = ntohl(htons(cpi)); 147105197Ssam } 148105197Ssam 149105197Ssam /* 150105197Ssam * Find the SA and (indirectly) call the appropriate 151105197Ssam * kernel crypto routine. The resulting mbuf chain is a valid 152105197Ssam * IP packet ready to go through input processing. 153105197Ssam */ 154105197Ssam bzero(&dst_address, sizeof (dst_address)); 155105197Ssam dst_address.sa.sa_family = af; 156105197Ssam switch (af) { 157105197Ssam#ifdef INET 158105197Ssam case AF_INET: 159105197Ssam dst_address.sin.sin_len = sizeof(struct sockaddr_in); 160105197Ssam m_copydata(m, offsetof(struct ip, ip_dst), 161105197Ssam sizeof(struct in_addr), 162105197Ssam (caddr_t) &dst_address.sin.sin_addr); 163105197Ssam break; 164105197Ssam#endif /* INET */ 165105197Ssam#ifdef INET6 166105197Ssam case AF_INET6: 167105197Ssam dst_address.sin6.sin6_len = sizeof(struct sockaddr_in6); 168105197Ssam m_copydata(m, offsetof(struct ip6_hdr, ip6_dst), 169105197Ssam sizeof(struct in6_addr), 170105197Ssam (caddr_t) &dst_address.sin6.sin6_addr); 171105197Ssam break; 172105197Ssam#endif /* INET6 */ 173105197Ssam default: 174120585Ssam DPRINTF(("%s: unsupported protocol family %u\n", __func__, af)); 175105197Ssam m_freem(m); 176105197Ssam IPSEC_ISTAT(sproto, espstat.esps_nopf, ahstat.ahs_nopf, 177105197Ssam ipcompstat.ipcomps_nopf); 178105197Ssam return EPFNOSUPPORT; 179105197Ssam } 180105197Ssam 181105197Ssam /* NB: only pass dst since key_allocsa follows RFC2401 */ 182105197Ssam sav = KEY_ALLOCSA(&dst_address, sproto, spi); 183105197Ssam if (sav == NULL) { 184120585Ssam DPRINTF(("%s: no key association found for SA %s/%08lx/%u\n", 185120585Ssam __func__, ipsec_address(&dst_address), 186105197Ssam (u_long) ntohl(spi), sproto)); 187105197Ssam IPSEC_ISTAT(sproto, espstat.esps_notdb, ahstat.ahs_notdb, 188105197Ssam ipcompstat.ipcomps_notdb); 189105197Ssam m_freem(m); 190105197Ssam return ENOENT; 191105197Ssam } 192105197Ssam 193105197Ssam if (sav->tdb_xform == NULL) { 194120585Ssam DPRINTF(("%s: attempted to use uninitialized SA %s/%08lx/%u\n", 195120585Ssam __func__, ipsec_address(&dst_address), 196105197Ssam (u_long) ntohl(spi), sproto)); 197105197Ssam IPSEC_ISTAT(sproto, espstat.esps_noxform, ahstat.ahs_noxform, 198105197Ssam ipcompstat.ipcomps_noxform); 199105197Ssam KEY_FREESAV(&sav); 200105197Ssam m_freem(m); 201105197Ssam return ENXIO; 202105197Ssam } 203105197Ssam 204105197Ssam /* 205105197Ssam * Call appropriate transform and return -- callback takes care of 206105197Ssam * everything else. 207105197Ssam */ 208105197Ssam error = (*sav->tdb_xform->xf_input)(m, sav, skip, protoff); 209105197Ssam KEY_FREESAV(&sav); 210105197Ssam return error; 211105197Ssam} 212105197Ssam 213105197Ssam#ifdef INET 214105197Ssam/* 215105197Ssam * Common input handler for IPv4 AH, ESP, and IPCOMP. 216105197Ssam */ 217105197Ssamint 218105197Ssamipsec4_common_input(struct mbuf *m, ...) 219105197Ssam{ 220105197Ssam va_list ap; 221105197Ssam int off, nxt; 222105197Ssam 223105197Ssam va_start(ap, m); 224105197Ssam off = va_arg(ap, int); 225105197Ssam nxt = va_arg(ap, int); 226105197Ssam va_end(ap); 227105197Ssam 228105197Ssam return ipsec_common_input(m, off, offsetof(struct ip, ip_p), 229105197Ssam AF_INET, nxt); 230105197Ssam} 231105197Ssam 232106680Ssamvoid 233106680Ssamah4_input(struct mbuf *m, int off) 234106680Ssam{ 235106680Ssam ipsec4_common_input(m, off, IPPROTO_AH); 236106680Ssam} 237120585Ssamvoid 238120585Ssamah4_ctlinput(int cmd, struct sockaddr *sa, void *v) 239120585Ssam{ 240120585Ssam if (sa->sa_family == AF_INET && 241120585Ssam sa->sa_len == sizeof(struct sockaddr_in)) 242120585Ssam ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_AH); 243120585Ssam} 244106680Ssam 245106680Ssamvoid 246106680Ssamesp4_input(struct mbuf *m, int off) 247106680Ssam{ 248106680Ssam ipsec4_common_input(m, off, IPPROTO_ESP); 249106680Ssam} 250120585Ssamvoid 251120585Ssamesp4_ctlinput(int cmd, struct sockaddr *sa, void *v) 252120585Ssam{ 253120585Ssam if (sa->sa_family == AF_INET && 254120585Ssam sa->sa_len == sizeof(struct sockaddr_in)) 255120585Ssam ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_ESP); 256120585Ssam} 257106680Ssam 258106680Ssamvoid 259106680Ssamipcomp4_input(struct mbuf *m, int off) 260106680Ssam{ 261106680Ssam ipsec4_common_input(m, off, IPPROTO_IPCOMP); 262106680Ssam} 263106680Ssam 264105197Ssam/* 265105197Ssam * IPsec input callback for INET protocols. 266105197Ssam * This routine is called as the transform callback. 267105197Ssam * Takes care of filtering and other sanity checks on 268105197Ssam * the processed packet. 269105197Ssam */ 270105197Ssamint 271105197Ssamipsec4_common_input_cb(struct mbuf *m, struct secasvar *sav, 272105197Ssam int skip, int protoff, struct m_tag *mt) 273105197Ssam{ 274105197Ssam int prot, af, sproto; 275105197Ssam struct ip *ip; 276105197Ssam struct m_tag *mtag; 277105197Ssam struct tdb_ident *tdbi; 278105197Ssam struct secasindex *saidx; 279105197Ssam int error; 280105197Ssam 281120585Ssam IPSEC_SPLASSERT_SOFTNET(__func__); 282105197Ssam 283120585Ssam IPSEC_ASSERT(m != NULL, ("null mbuf")); 284120585Ssam IPSEC_ASSERT(sav != NULL, ("null SA")); 285120585Ssam IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); 286105197Ssam saidx = &sav->sah->saidx; 287105197Ssam af = saidx->dst.sa.sa_family; 288120585Ssam IPSEC_ASSERT(af == AF_INET, ("unexpected af %u", af)); 289105197Ssam sproto = saidx->proto; 290120585Ssam IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH || 291105197Ssam sproto == IPPROTO_IPCOMP, 292120585Ssam ("unexpected security protocol %u", sproto)); 293105197Ssam 294105197Ssam /* Sanity check */ 295105197Ssam if (m == NULL) { 296120585Ssam DPRINTF(("%s: null mbuf", __func__)); 297105197Ssam IPSEC_ISTAT(sproto, espstat.esps_badkcr, ahstat.ahs_badkcr, 298105197Ssam ipcompstat.ipcomps_badkcr); 299105197Ssam KEY_FREESAV(&sav); 300105197Ssam return EINVAL; 301105197Ssam } 302105197Ssam 303105197Ssam if (skip != 0) { 304105197Ssam /* Fix IPv4 header */ 305105197Ssam if (m->m_len < skip && (m = m_pullup(m, skip)) == NULL) { 306120585Ssam DPRINTF(("%s: processing failed for SA %s/%08lx\n", 307120585Ssam __func__, ipsec_address(&sav->sah->saidx.dst), 308105197Ssam (u_long) ntohl(sav->spi))); 309105197Ssam IPSEC_ISTAT(sproto, espstat.esps_hdrops, ahstat.ahs_hdrops, 310105197Ssam ipcompstat.ipcomps_hdrops); 311105197Ssam error = ENOBUFS; 312105197Ssam goto bad; 313105197Ssam } 314105197Ssam 315105197Ssam ip = mtod(m, struct ip *); 316105197Ssam ip->ip_len = htons(m->m_pkthdr.len); 317105197Ssam ip->ip_off = htons(ip->ip_off); 318105197Ssam ip->ip_sum = 0; 319105197Ssam ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 320105197Ssam } else { 321105197Ssam ip = mtod(m, struct ip *); 322105197Ssam } 323105197Ssam prot = ip->ip_p; 324105197Ssam 325159215Sgnn#ifdef notyet 326105197Ssam /* IP-in-IP encapsulation */ 327105197Ssam if (prot == IPPROTO_IPIP) { 328105197Ssam struct ip ipn; 329105197Ssam 330118888Ssam if (m->m_pkthdr.len - skip < sizeof(struct ip)) { 331118888Ssam IPSEC_ISTAT(sproto, espstat.esps_hdrops, 332118888Ssam ahstat.ahs_hdrops, 333118888Ssam ipcompstat.ipcomps_hdrops); 334118888Ssam error = EINVAL; 335118888Ssam goto bad; 336118888Ssam } 337105197Ssam /* ipn will now contain the inner IPv4 header */ 338105197Ssam m_copydata(m, ip->ip_hl << 2, sizeof(struct ip), 339105197Ssam (caddr_t) &ipn); 340105197Ssam 341105197Ssam /* XXX PROXY address isn't recorded in SAH */ 342105197Ssam /* 343105197Ssam * Check that the inner source address is the same as 344105197Ssam * the proxy address, if available. 345105197Ssam */ 346105197Ssam if ((saidx->proxy.sa.sa_family == AF_INET && 347105197Ssam saidx->proxy.sin.sin_addr.s_addr != 348105197Ssam INADDR_ANY && 349105197Ssam ipn.ip_src.s_addr != 350105197Ssam saidx->proxy.sin.sin_addr.s_addr) || 351105197Ssam (saidx->proxy.sa.sa_family != AF_INET && 352105197Ssam saidx->proxy.sa.sa_family != 0)) { 353105197Ssam 354120585Ssam DPRINTF(("%s: inner source address %s doesn't " 355120585Ssam "correspond to expected proxy source %s, " 356120585Ssam "SA %s/%08lx\n", __func__, 357105197Ssam inet_ntoa4(ipn.ip_src), 358105197Ssam ipsp_address(saidx->proxy), 359105197Ssam ipsp_address(saidx->dst), 360105197Ssam (u_long) ntohl(sav->spi))); 361105197Ssam 362105197Ssam IPSEC_ISTAT(sproto, espstat.esps_pdrops, 363105197Ssam ahstat.ahs_pdrops, 364105197Ssam ipcompstat.ipcomps_pdrops); 365105197Ssam error = EACCES; 366105197Ssam goto bad; 367105197Ssam } 368105197Ssam } 369159237Spjd#ifdef INET6 370105197Ssam /* IPv6-in-IP encapsulation. */ 371105197Ssam if (prot == IPPROTO_IPV6) { 372105197Ssam struct ip6_hdr ip6n; 373105197Ssam 374118888Ssam if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) { 375118888Ssam IPSEC_ISTAT(sproto, espstat.esps_hdrops, 376118888Ssam ahstat.ahs_hdrops, 377118888Ssam ipcompstat.ipcomps_hdrops); 378118888Ssam error = EINVAL; 379118888Ssam goto bad; 380118888Ssam } 381105197Ssam /* ip6n will now contain the inner IPv6 header. */ 382105197Ssam m_copydata(m, ip->ip_hl << 2, sizeof(struct ip6_hdr), 383105197Ssam (caddr_t) &ip6n); 384105197Ssam 385105197Ssam /* 386105197Ssam * Check that the inner source address is the same as 387105197Ssam * the proxy address, if available. 388105197Ssam */ 389105197Ssam if ((saidx->proxy.sa.sa_family == AF_INET6 && 390105197Ssam !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) && 391105197Ssam !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src, 392105197Ssam &saidx->proxy.sin6.sin6_addr)) || 393105197Ssam (saidx->proxy.sa.sa_family != AF_INET6 && 394105197Ssam saidx->proxy.sa.sa_family != 0)) { 395105197Ssam 396120585Ssam DPRINTF(("%s: inner source address %s doesn't " 397120585Ssam "correspond to expected proxy source %s, " 398120585Ssam "SA %s/%08lx\n", __func__, 399105197Ssam ip6_sprintf(&ip6n.ip6_src), 400105197Ssam ipsec_address(&saidx->proxy), 401105197Ssam ipsec_address(&saidx->dst), 402105197Ssam (u_long) ntohl(sav->spi))); 403105197Ssam 404105197Ssam IPSEC_ISTAT(sproto, espstat.esps_pdrops, 405105197Ssam ahstat.ahs_pdrops, 406105197Ssam ipcompstat.ipcomps_pdrops); 407105197Ssam error = EACCES; 408105197Ssam goto bad; 409105197Ssam } 410105197Ssam } 411105197Ssam#endif /* INET6 */ 412159215Sgnn#endif /*XXX*/ 413105197Ssam 414105197Ssam /* 415105197Ssam * Record what we've done to the packet (under what SA it was 416105197Ssam * processed). If we've been passed an mtag, it means the packet 417105197Ssam * was already processed by an ethernet/crypto combo card and 418105197Ssam * thus has a tag attached with all the right information, but 419105197Ssam * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to 420105197Ssam * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type. 421105197Ssam */ 422105197Ssam if (mt == NULL && sproto != IPPROTO_IPCOMP) { 423105197Ssam mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE, 424105197Ssam sizeof(struct tdb_ident), M_NOWAIT); 425105197Ssam if (mtag == NULL) { 426120585Ssam DPRINTF(("%s: failed to get tag\n", __func__)); 427105197Ssam IPSEC_ISTAT(sproto, espstat.esps_hdrops, 428105197Ssam ahstat.ahs_hdrops, ipcompstat.ipcomps_hdrops); 429105197Ssam error = ENOMEM; 430105197Ssam goto bad; 431105197Ssam } 432105197Ssam 433105197Ssam tdbi = (struct tdb_ident *)(mtag + 1); 434105197Ssam bcopy(&saidx->dst, &tdbi->dst, saidx->dst.sa.sa_len); 435105197Ssam tdbi->proto = sproto; 436105197Ssam tdbi->spi = sav->spi; 437105197Ssam 438105197Ssam m_tag_prepend(m, mtag); 439105197Ssam } else { 440105197Ssam mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE; 441105197Ssam /* XXX do we need to mark m_flags??? */ 442105197Ssam } 443105197Ssam 444105197Ssam key_sa_recordxfer(sav, m); /* record data transfer */ 445105197Ssam 446159965Sthompsa#ifdef DEV_ENC 447105197Ssam /* 448159965Sthompsa * Pass the mbuf to enc0 for bpf and pfil. We will filter the IPIP 449159965Sthompsa * packet later after it has been decapsulated. 450159965Sthompsa */ 451159965Sthompsa ipsec_bpf(m, sav, AF_INET); 452159965Sthompsa 453159965Sthompsa if (prot != IPPROTO_IPIP) 454159965Sthompsa if ((error = ipsec_filter(&m, 1)) != 0) 455159965Sthompsa return (error); 456159965Sthompsa#endif 457159965Sthompsa 458159965Sthompsa /* 459105197Ssam * Re-dispatch via software interrupt. 460105197Ssam */ 461134391Sandre if ((error = netisr_queue(NETISR_IP, m))) { 462105197Ssam IPSEC_ISTAT(sproto, espstat.esps_qfull, ahstat.ahs_qfull, 463105197Ssam ipcompstat.ipcomps_qfull); 464105197Ssam 465120585Ssam DPRINTF(("%s: queue full; proto %u packet dropped\n", 466120585Ssam __func__, sproto)); 467134391Sandre return error; 468105197Ssam } 469105197Ssam return 0; 470105197Ssambad: 471105197Ssam m_freem(m); 472105197Ssam return error; 473105197Ssam} 474120585Ssam 475120585Ssamvoid 476120585Ssamipsec4_common_ctlinput(int cmd, struct sockaddr *sa, void *v, int proto) 477120585Ssam{ 478120585Ssam /* XXX nothing just yet */ 479120585Ssam} 480105197Ssam#endif /* INET */ 481105197Ssam 482105197Ssam#ifdef INET6 483105197Ssam/* IPv6 AH wrapper. */ 484105197Ssamint 485105197Ssamipsec6_common_input(struct mbuf **mp, int *offp, int proto) 486105197Ssam{ 487105197Ssam int l = 0; 488105197Ssam int protoff; 489105197Ssam struct ip6_ext ip6e; 490105197Ssam 491105197Ssam if (*offp < sizeof(struct ip6_hdr)) { 492120585Ssam DPRINTF(("%s: bad offset %u\n", __func__, *offp)); 493105197Ssam return IPPROTO_DONE; 494105197Ssam } else if (*offp == sizeof(struct ip6_hdr)) { 495105197Ssam protoff = offsetof(struct ip6_hdr, ip6_nxt); 496105197Ssam } else { 497105197Ssam /* Chase down the header chain... */ 498105197Ssam protoff = sizeof(struct ip6_hdr); 499105197Ssam 500105197Ssam do { 501105197Ssam protoff += l; 502105197Ssam m_copydata(*mp, protoff, sizeof(ip6e), 503105197Ssam (caddr_t) &ip6e); 504105197Ssam 505105197Ssam if (ip6e.ip6e_nxt == IPPROTO_AH) 506105197Ssam l = (ip6e.ip6e_len + 2) << 2; 507105197Ssam else 508105197Ssam l = (ip6e.ip6e_len + 1) << 3; 509120585Ssam IPSEC_ASSERT(l > 0, ("l went zero or negative")); 510105197Ssam } while (protoff + l < *offp); 511105197Ssam 512105197Ssam /* Malformed packet check */ 513105197Ssam if (protoff + l != *offp) { 514120585Ssam DPRINTF(("%s: bad packet header chain, protoff %u, " 515120585Ssam "l %u, off %u\n", __func__, protoff, l, *offp)); 516105197Ssam IPSEC_ISTAT(proto, espstat.esps_hdrops, 517105197Ssam ahstat.ahs_hdrops, 518105197Ssam ipcompstat.ipcomps_hdrops); 519105197Ssam m_freem(*mp); 520105197Ssam *mp = NULL; 521105197Ssam return IPPROTO_DONE; 522105197Ssam } 523105197Ssam protoff += offsetof(struct ip6_ext, ip6e_nxt); 524105197Ssam } 525105197Ssam (void) ipsec_common_input(*mp, *offp, protoff, AF_INET6, proto); 526105197Ssam return IPPROTO_DONE; 527105197Ssam} 528105197Ssam 529105197Ssam/* 530105197Ssam * IPsec input callback, called by the transform callback. Takes care of 531105197Ssam * filtering and other sanity checks on the processed packet. 532105197Ssam */ 533105197Ssamint 534105197Ssamipsec6_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip, int protoff, 535105197Ssam struct m_tag *mt) 536105197Ssam{ 537105197Ssam int prot, af, sproto; 538105197Ssam struct ip6_hdr *ip6; 539105197Ssam struct m_tag *mtag; 540105197Ssam struct tdb_ident *tdbi; 541105197Ssam struct secasindex *saidx; 542105197Ssam int nxt; 543105197Ssam u_int8_t nxt8; 544105197Ssam int error, nest; 545105197Ssam 546120585Ssam IPSEC_ASSERT(m != NULL, ("null mbuf")); 547120585Ssam IPSEC_ASSERT(sav != NULL, ("null SA")); 548120585Ssam IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); 549105197Ssam saidx = &sav->sah->saidx; 550105197Ssam af = saidx->dst.sa.sa_family; 551120585Ssam IPSEC_ASSERT(af == AF_INET6, ("unexpected af %u", af)); 552105197Ssam sproto = saidx->proto; 553120585Ssam IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH || 554105197Ssam sproto == IPPROTO_IPCOMP, 555120585Ssam ("unexpected security protocol %u", sproto)); 556105197Ssam 557105197Ssam /* Sanity check */ 558105197Ssam if (m == NULL) { 559120585Ssam DPRINTF(("%s: null mbuf", __func__)); 560105197Ssam IPSEC_ISTAT(sproto, espstat.esps_badkcr, ahstat.ahs_badkcr, 561105197Ssam ipcompstat.ipcomps_badkcr); 562105197Ssam error = EINVAL; 563105197Ssam goto bad; 564105197Ssam } 565105197Ssam 566105197Ssam /* Fix IPv6 header */ 567105197Ssam if (m->m_len < sizeof(struct ip6_hdr) && 568105197Ssam (m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { 569105197Ssam 570120585Ssam DPRINTF(("%s: processing failed for SA %s/%08lx\n", 571120585Ssam __func__, ipsec_address(&sav->sah->saidx.dst), 572105197Ssam (u_long) ntohl(sav->spi))); 573105197Ssam 574105197Ssam IPSEC_ISTAT(sproto, espstat.esps_hdrops, ahstat.ahs_hdrops, 575105197Ssam ipcompstat.ipcomps_hdrops); 576105197Ssam error = EACCES; 577105197Ssam goto bad; 578105197Ssam } 579105197Ssam 580105197Ssam ip6 = mtod(m, struct ip6_hdr *); 581105197Ssam ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 582105197Ssam 583105197Ssam /* Save protocol */ 584105197Ssam m_copydata(m, protoff, 1, (unsigned char *) &prot); 585105197Ssam 586159215Sgnn#ifdef notyet 587105197Ssam#ifdef INET 588105197Ssam /* IP-in-IP encapsulation */ 589105197Ssam if (prot == IPPROTO_IPIP) { 590105197Ssam struct ip ipn; 591105197Ssam 592118888Ssam if (m->m_pkthdr.len - skip < sizeof(struct ip)) { 593118888Ssam IPSEC_ISTAT(sproto, espstat.esps_hdrops, 594118888Ssam ahstat.ahs_hdrops, 595118888Ssam ipcompstat.ipcomps_hdrops); 596118888Ssam error = EINVAL; 597118888Ssam goto bad; 598118888Ssam } 599105197Ssam /* ipn will now contain the inner IPv4 header */ 600105197Ssam m_copydata(m, skip, sizeof(struct ip), (caddr_t) &ipn); 601105197Ssam 602105197Ssam /* 603105197Ssam * Check that the inner source address is the same as 604105197Ssam * the proxy address, if available. 605105197Ssam */ 606105197Ssam if ((saidx->proxy.sa.sa_family == AF_INET && 607105197Ssam saidx->proxy.sin.sin_addr.s_addr != INADDR_ANY && 608105197Ssam ipn.ip_src.s_addr != saidx->proxy.sin.sin_addr.s_addr) || 609105197Ssam (saidx->proxy.sa.sa_family != AF_INET && 610105197Ssam saidx->proxy.sa.sa_family != 0)) { 611105197Ssam 612120585Ssam DPRINTF(("%s: inner source address %s doesn't " 613120585Ssam "correspond to expected proxy source %s, " 614120585Ssam "SA %s/%08lx\n", __func__, 615105197Ssam inet_ntoa4(ipn.ip_src), 616105197Ssam ipsec_address(&saidx->proxy), 617105197Ssam ipsec_address(&saidx->dst), 618105197Ssam (u_long) ntohl(sav->spi))); 619105197Ssam 620105197Ssam IPSEC_ISTATsproto, (espstat.esps_pdrops, 621105197Ssam ahstat.ahs_pdrops, ipcompstat.ipcomps_pdrops); 622105197Ssam error = EACCES; 623105197Ssam goto bad; 624105197Ssam } 625105197Ssam } 626105197Ssam#endif /* INET */ 627105197Ssam 628105197Ssam /* IPv6-in-IP encapsulation */ 629105197Ssam if (prot == IPPROTO_IPV6) { 630105197Ssam struct ip6_hdr ip6n; 631105197Ssam 632118888Ssam if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) { 633118888Ssam IPSEC_ISTAT(sproto, espstat.esps_hdrops, 634118888Ssam ahstat.ahs_hdrops, 635118888Ssam ipcompstat.ipcomps_hdrops); 636118888Ssam error = EINVAL; 637118888Ssam goto bad; 638118888Ssam } 639105197Ssam /* ip6n will now contain the inner IPv6 header. */ 640105197Ssam m_copydata(m, skip, sizeof(struct ip6_hdr), 641105197Ssam (caddr_t) &ip6n); 642105197Ssam 643105197Ssam /* 644105197Ssam * Check that the inner source address is the same as 645105197Ssam * the proxy address, if available. 646105197Ssam */ 647105197Ssam if ((saidx->proxy.sa.sa_family == AF_INET6 && 648105197Ssam !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) && 649105197Ssam !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src, 650105197Ssam &saidx->proxy.sin6.sin6_addr)) || 651105197Ssam (saidx->proxy.sa.sa_family != AF_INET6 && 652105197Ssam saidx->proxy.sa.sa_family != 0)) { 653105197Ssam 654120585Ssam DPRINTF(("%s: inner source address %s doesn't " 655120585Ssam "correspond to expected proxy source %s, " 656120585Ssam "SA %s/%08lx\n", __func__, 657105197Ssam ip6_sprintf(&ip6n.ip6_src), 658105197Ssam ipsec_address(&saidx->proxy), 659105197Ssam ipsec_address(&saidx->dst), 660105197Ssam (u_long) ntohl(sav->spi))); 661105197Ssam 662105197Ssam IPSEC_ISTAT(sproto, espstat.esps_pdrops, 663105197Ssam ahstat.ahs_pdrops, ipcompstat.ipcomps_pdrops); 664105197Ssam error = EACCES; 665105197Ssam goto bad; 666105197Ssam } 667159215Sgnn } 668105197Ssam#endif /*XXX*/ 669105197Ssam 670105197Ssam /* 671105197Ssam * Record what we've done to the packet (under what SA it was 672105197Ssam * processed). If we've been passed an mtag, it means the packet 673105197Ssam * was already processed by an ethernet/crypto combo card and 674105197Ssam * thus has a tag attached with all the right information, but 675105197Ssam * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to 676105197Ssam * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type. 677105197Ssam */ 678105197Ssam if (mt == NULL && sproto != IPPROTO_IPCOMP) { 679105197Ssam mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE, 680105197Ssam sizeof(struct tdb_ident), M_NOWAIT); 681105197Ssam if (mtag == NULL) { 682120585Ssam DPRINTF(("%s: failed to get tag\n", __func__)); 683105197Ssam IPSEC_ISTAT(sproto, espstat.esps_hdrops, 684105197Ssam ahstat.ahs_hdrops, ipcompstat.ipcomps_hdrops); 685105197Ssam error = ENOMEM; 686105197Ssam goto bad; 687105197Ssam } 688105197Ssam 689105197Ssam tdbi = (struct tdb_ident *)(mtag + 1); 690105197Ssam bcopy(&saidx->dst, &tdbi->dst, sizeof(union sockaddr_union)); 691105197Ssam tdbi->proto = sproto; 692105197Ssam tdbi->spi = sav->spi; 693105197Ssam 694105197Ssam m_tag_prepend(m, mtag); 695105197Ssam } else { 696120585Ssam if (mt != NULL) 697120585Ssam mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE; 698105197Ssam /* XXX do we need to mark m_flags??? */ 699105197Ssam } 700105197Ssam 701105197Ssam key_sa_recordxfer(sav, m); 702105197Ssam 703105197Ssam /* Retrieve new protocol */ 704105197Ssam m_copydata(m, protoff, sizeof(u_int8_t), (caddr_t) &nxt8); 705105197Ssam 706105197Ssam /* 707105197Ssam * See the end of ip6_input for this logic. 708105197Ssam * IPPROTO_IPV[46] case will be processed just like other ones 709105197Ssam */ 710105197Ssam nest = 0; 711105197Ssam nxt = nxt8; 712105197Ssam while (nxt != IPPROTO_DONE) { 713105197Ssam if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { 714105197Ssam ip6stat.ip6s_toomanyhdr++; 715105197Ssam error = EINVAL; 716105197Ssam goto bad; 717105197Ssam } 718105197Ssam 719105197Ssam /* 720105197Ssam * Protection against faulty packet - there should be 721105197Ssam * more sanity checks in header chain processing. 722105197Ssam */ 723105197Ssam if (m->m_pkthdr.len < skip) { 724105197Ssam ip6stat.ip6s_tooshort++; 725105197Ssam in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); 726105197Ssam error = EINVAL; 727105197Ssam goto bad; 728105197Ssam } 729105197Ssam /* 730105197Ssam * Enforce IPsec policy checking if we are seeing last header. 731105197Ssam * note that we do not visit this with protocols with pcb layer 732105197Ssam * code - like udp/tcp/raw ip. 733105197Ssam */ 734105197Ssam if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 && 735105197Ssam ipsec6_in_reject(m, NULL)) { 736105197Ssam error = EINVAL; 737105197Ssam goto bad; 738105197Ssam } 739105197Ssam nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &skip, nxt); 740105197Ssam } 741105197Ssam return 0; 742105197Ssambad: 743105197Ssam if (m) 744105197Ssam m_freem(m); 745105197Ssam return error; 746105197Ssam} 747120585Ssam 748120585Ssamvoid 749120585Ssamesp6_ctlinput(int cmd, struct sockaddr *sa, void *d) 750120585Ssam{ 751120585Ssam if (sa->sa_family != AF_INET6 || 752120585Ssam sa->sa_len != sizeof(struct sockaddr_in6)) 753120585Ssam return; 754120585Ssam if ((unsigned)cmd >= PRC_NCMDS) 755120585Ssam return; 756120585Ssam 757120585Ssam /* if the parameter is from icmp6, decode it. */ 758120585Ssam if (d != NULL) { 759120585Ssam struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d; 760120585Ssam struct mbuf *m = ip6cp->ip6c_m; 761120585Ssam int off = ip6cp->ip6c_off; 762120585Ssam 763120585Ssam struct ip6ctlparam ip6cp1; 764120585Ssam 765120585Ssam /* 766120585Ssam * Notify the error to all possible sockets via pfctlinput2. 767120585Ssam * Since the upper layer information (such as protocol type, 768120585Ssam * source and destination ports) is embedded in the encrypted 769120585Ssam * data and might have been cut, we can't directly call 770120585Ssam * an upper layer ctlinput function. However, the pcbnotify 771120585Ssam * function will consider source and destination addresses 772120585Ssam * as well as the flow info value, and may be able to find 773120585Ssam * some PCB that should be notified. 774120585Ssam * Although pfctlinput2 will call esp6_ctlinput(), there is 775120585Ssam * no possibility of an infinite loop of function calls, 776120585Ssam * because we don't pass the inner IPv6 header. 777120585Ssam */ 778120585Ssam bzero(&ip6cp1, sizeof(ip6cp1)); 779120585Ssam ip6cp1.ip6c_src = ip6cp->ip6c_src; 780120585Ssam pfctlinput2(cmd, sa, (void *)&ip6cp1); 781120585Ssam 782120585Ssam /* 783120585Ssam * Then go to special cases that need ESP header information. 784120585Ssam * XXX: We assume that when ip6 is non NULL, 785120585Ssam * M and OFF are valid. 786120585Ssam */ 787120585Ssam 788120585Ssam if (cmd == PRC_MSGSIZE) { 789120585Ssam struct secasvar *sav; 790120585Ssam u_int32_t spi; 791120585Ssam int valid; 792120585Ssam 793120585Ssam /* check header length before using m_copydata */ 794120585Ssam if (m->m_pkthdr.len < off + sizeof (struct esp)) 795120585Ssam return; 796120585Ssam m_copydata(m, off + offsetof(struct esp, esp_spi), 797120585Ssam sizeof(u_int32_t), (caddr_t) &spi); 798120585Ssam /* 799120585Ssam * Check to see if we have a valid SA corresponding to 800120585Ssam * the address in the ICMP message payload. 801120585Ssam */ 802120585Ssam sav = KEY_ALLOCSA((union sockaddr_union *)sa, 803120585Ssam IPPROTO_ESP, spi); 804120585Ssam valid = (sav != NULL); 805120585Ssam if (sav) 806120585Ssam KEY_FREESAV(&sav); 807120585Ssam 808120585Ssam /* XXX Further validation? */ 809120585Ssam 810120585Ssam /* 811120585Ssam * Depending on whether the SA is "valid" and 812120585Ssam * routing table size (mtudisc_{hi,lo}wat), we will: 813120585Ssam * - recalcurate the new MTU and create the 814120585Ssam * corresponding routing entry, or 815120585Ssam * - ignore the MTU change notification. 816120585Ssam */ 817120585Ssam icmp6_mtudisc_update(ip6cp, valid); 818120585Ssam } 819120585Ssam } else { 820120585Ssam /* we normally notify any pcb here */ 821120585Ssam } 822120585Ssam} 823105197Ssam#endif /* INET6 */ 824