| 1 | /* $NetBSD: ipsec_input.c,v 1.36 2016/06/10 13:31:44 ozaki-r Exp $ */ |
| 2 | /* $FreeBSD: /usr/local/www/cvsroot/FreeBSD/src/sys/netipsec/ipsec_input.c,v 1.2.4.2 2003/03/28 20:32:53 sam Exp $ */ |
| 3 | /* $OpenBSD: ipsec_input.c,v 1.63 2003/02/20 18:35:43 deraadt Exp $ */ |
| 4 | |
| 5 | /* |
| 6 | * The authors of this code are John Ioannidis (ji@tla.org), |
| 7 | * Angelos D. Keromytis (kermit@csd.uch.gr) and |
| 8 | * Niels Provos (provos@physnet.uni-hamburg.de). |
| 9 | * |
| 10 | * This code was written by John Ioannidis for BSD/OS in Athens, Greece, |
| 11 | * in November 1995. |
| 12 | * |
| 13 | * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996, |
| 14 | * by Angelos D. Keromytis. |
| 15 | * |
| 16 | * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis |
| 17 | * and Niels Provos. |
| 18 | * |
| 19 | * Additional features in 1999 by Angelos D. Keromytis. |
| 20 | * |
| 21 | * Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis, |
| 22 | * Angelos D. Keromytis and Niels Provos. |
| 23 | * Copyright (c) 2001, Angelos D. Keromytis. |
| 24 | * |
| 25 | * Permission to use, copy, and modify this software with or without fee |
| 26 | * is hereby granted, provided that this entire notice is included in |
| 27 | * all copies of any software which is or includes a copy or |
| 28 | * modification of this software. |
| 29 | * You may use this code under the GNU public license if you so wish. Please |
| 30 | * contribute changes back to the authors under this freer than GPL license |
| 31 | * so that we may further the use of strong encryption without limitations to |
| 32 | * all. |
| 33 | * |
| 34 | * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR |
| 35 | * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY |
| 36 | * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE |
| 37 | * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR |
| 38 | * PURPOSE. |
| 39 | */ |
| 40 | |
| 41 | #include <sys/cdefs.h> |
| 42 | __KERNEL_RCSID(0, "$NetBSD: ipsec_input.c,v 1.36 2016/06/10 13:31:44 ozaki-r Exp $" ); |
| 43 | |
| 44 | /* |
| 45 | * IPsec input processing. |
| 46 | */ |
| 47 | |
| 48 | #include "opt_inet.h" |
| 49 | #ifdef __FreeBSD__ |
| 50 | #include "opt_inet6.h" |
| 51 | #endif |
| 52 | |
| 53 | #include <sys/param.h> |
| 54 | #include <sys/systm.h> |
| 55 | #include <sys/malloc.h> |
| 56 | #include <sys/mbuf.h> |
| 57 | #include <sys/domain.h> |
| 58 | #include <sys/protosw.h> |
| 59 | #include <sys/socket.h> |
| 60 | #include <sys/errno.h> |
| 61 | #include <sys/syslog.h> |
| 62 | |
| 63 | #include <net/if.h> |
| 64 | #include <net/route.h> |
| 65 | |
| 66 | #include <netinet/in.h> |
| 67 | #include <netinet/in_systm.h> |
| 68 | #include <netinet/ip.h> |
| 69 | #include <netinet/ip_var.h> |
| 70 | #include <netinet/in_var.h> |
| 71 | #include <netinet/in_proto.h> |
| 72 | |
| 73 | #include <netinet/ip6.h> |
| 74 | #ifdef INET6 |
| 75 | #include <netinet6/ip6_var.h> |
| 76 | #include <netinet6/ip6_private.h> |
| 77 | #include <netinet6/scope6_var.h> |
| 78 | #endif |
| 79 | #include <netinet/in_pcb.h> |
| 80 | #ifdef INET6 |
| 81 | #include <netinet/icmp6.h> |
| 82 | #endif |
| 83 | |
| 84 | #include <netipsec/ipsec.h> |
| 85 | #include <netipsec/ipsec_private.h> |
| 86 | #ifdef INET6 |
| 87 | #include <netipsec/ipsec6.h> |
| 88 | #endif |
| 89 | #include <netipsec/ah_var.h> |
| 90 | #include <netipsec/esp.h> |
| 91 | #include <netipsec/esp_var.h> |
| 92 | #include <netipsec/ipcomp_var.h> |
| 93 | |
| 94 | #include <netipsec/key.h> |
| 95 | #include <netipsec/keydb.h> |
| 96 | |
| 97 | #include <netipsec/xform.h> |
| 98 | #include <netinet6/ip6protosw.h> |
| 99 | |
| 100 | #include <netipsec/ipsec_osdep.h> |
| 101 | |
| 102 | #include <net/net_osdep.h> |
| 103 | |
| 104 | #define IPSEC_ISTAT(p, x, y, z) \ |
| 105 | do { \ |
| 106 | switch (p) { \ |
| 107 | case IPPROTO_ESP: \ |
| 108 | ESP_STATINC(x); \ |
| 109 | break; \ |
| 110 | case IPPROTO_AH: \ |
| 111 | AH_STATINC(y); \ |
| 112 | break; \ |
| 113 | default: \ |
| 114 | IPCOMP_STATINC(z); \ |
| 115 | break; \ |
| 116 | } \ |
| 117 | } while (/*CONSTCOND*/0) |
| 118 | |
| 119 | /* |
| 120 | * ipsec_common_input gets called when an IPsec-protected packet |
| 121 | * is received by IPv4 or IPv6. It's job is to find the right SA |
| 122 | # and call the appropriate transform. The transform callback |
| 123 | * takes care of further processing (like ingress filtering). |
| 124 | */ |
| 125 | static int |
| 126 | ipsec_common_input(struct mbuf *m, int skip, int protoff, int af, int sproto) |
| 127 | { |
| 128 | union sockaddr_union dst_address; |
| 129 | struct secasvar *sav; |
| 130 | u_int32_t spi; |
| 131 | u_int16_t sport; |
| 132 | u_int16_t dport; |
| 133 | int s, error; |
| 134 | |
| 135 | IPSEC_ISTAT(sproto, ESP_STAT_INPUT, AH_STAT_INPUT, |
| 136 | IPCOMP_STAT_INPUT); |
| 137 | |
| 138 | IPSEC_ASSERT(m != NULL, ("ipsec_common_input: null packet" )); |
| 139 | |
| 140 | if ((sproto == IPPROTO_ESP && !esp_enable) || |
| 141 | (sproto == IPPROTO_AH && !ah_enable) || |
| 142 | (sproto == IPPROTO_IPCOMP && !ipcomp_enable)) { |
| 143 | m_freem(m); |
| 144 | IPSEC_ISTAT(sproto, ESP_STAT_PDROPS, AH_STAT_PDROPS, |
| 145 | IPCOMP_STAT_PDROPS); |
| 146 | return EOPNOTSUPP; |
| 147 | } |
| 148 | |
| 149 | if (m->m_pkthdr.len - skip < 2 * sizeof (u_int32_t)) { |
| 150 | m_freem(m); |
| 151 | IPSEC_ISTAT(sproto, ESP_STAT_HDROPS, AH_STAT_HDROPS, |
| 152 | IPCOMP_STAT_HDROPS); |
| 153 | DPRINTF(("ipsec_common_input: packet too small\n" )); |
| 154 | return EINVAL; |
| 155 | } |
| 156 | |
| 157 | /* Retrieve the SPI from the relevant IPsec header */ |
| 158 | if (sproto == IPPROTO_ESP) |
| 159 | m_copydata(m, skip, sizeof(u_int32_t), &spi); |
| 160 | else if (sproto == IPPROTO_AH) |
| 161 | m_copydata(m, skip + sizeof(u_int32_t), sizeof(u_int32_t), &spi); |
| 162 | else if (sproto == IPPROTO_IPCOMP) { |
| 163 | u_int16_t cpi; |
| 164 | m_copydata(m, skip + sizeof(u_int16_t), sizeof(u_int16_t), &cpi); |
| 165 | spi = ntohl(htons(cpi)); |
| 166 | } else { |
| 167 | panic("ipsec_common_input called with bad protocol number :" |
| 168 | "%d\n" , sproto); |
| 169 | } |
| 170 | |
| 171 | |
| 172 | /* find the source port for NAT-T */ |
| 173 | nat_t_ports_get(m, &dport, &sport); |
| 174 | |
| 175 | /* |
| 176 | * Find the SA and (indirectly) call the appropriate |
| 177 | * kernel crypto routine. The resulting mbuf chain is a valid |
| 178 | * IP packet ready to go through input processing. |
| 179 | */ |
| 180 | memset(&dst_address, 0, sizeof (dst_address)); |
| 181 | dst_address.sa.sa_family = af; |
| 182 | switch (af) { |
| 183 | #ifdef INET |
| 184 | case AF_INET: |
| 185 | dst_address.sin.sin_len = sizeof(struct sockaddr_in); |
| 186 | m_copydata(m, offsetof(struct ip, ip_dst), |
| 187 | sizeof(struct in_addr), |
| 188 | &dst_address.sin.sin_addr); |
| 189 | break; |
| 190 | #endif /* INET */ |
| 191 | #ifdef INET6 |
| 192 | case AF_INET6: |
| 193 | dst_address.sin6.sin6_len = sizeof(struct sockaddr_in6); |
| 194 | m_copydata(m, offsetof(struct ip6_hdr, ip6_dst), |
| 195 | sizeof(struct in6_addr), |
| 196 | &dst_address.sin6.sin6_addr); |
| 197 | if (sa6_recoverscope(&dst_address.sin6)) { |
| 198 | m_freem(m); |
| 199 | return EINVAL; |
| 200 | } |
| 201 | break; |
| 202 | #endif /* INET6 */ |
| 203 | default: |
| 204 | DPRINTF(("ipsec_common_input: unsupported protocol " |
| 205 | "family %u\n" , af)); |
| 206 | m_freem(m); |
| 207 | IPSEC_ISTAT(sproto, ESP_STAT_NOPF, AH_STAT_NOPF, |
| 208 | IPCOMP_STAT_NOPF); |
| 209 | return EPFNOSUPPORT; |
| 210 | } |
| 211 | |
| 212 | s = splsoftnet(); |
| 213 | |
| 214 | /* NB: only pass dst since key_allocsa follows RFC2401 */ |
| 215 | sav = KEY_ALLOCSA(&dst_address, sproto, spi, sport, dport); |
| 216 | if (sav == NULL) { |
| 217 | DPRINTF(("ipsec_common_input: no key association found for" |
| 218 | " SA %s/%08lx/%u/%u\n" , |
| 219 | ipsec_address(&dst_address), |
| 220 | (u_long) ntohl(spi), sproto, ntohs(dport))); |
| 221 | IPSEC_ISTAT(sproto, ESP_STAT_NOTDB, AH_STAT_NOTDB, |
| 222 | IPCOMP_STAT_NOTDB); |
| 223 | splx(s); |
| 224 | m_freem(m); |
| 225 | return ENOENT; |
| 226 | } |
| 227 | |
| 228 | if (sav->tdb_xform == NULL) { |
| 229 | DPRINTF(("ipsec_common_input: attempted to use uninitialized" |
| 230 | " SA %s/%08lx/%u\n" , |
| 231 | ipsec_address(&dst_address), |
| 232 | (u_long) ntohl(spi), sproto)); |
| 233 | IPSEC_ISTAT(sproto, ESP_STAT_NOXFORM, AH_STAT_NOXFORM, |
| 234 | IPCOMP_STAT_NOXFORM); |
| 235 | KEY_FREESAV(&sav); |
| 236 | splx(s); |
| 237 | m_freem(m); |
| 238 | return ENXIO; |
| 239 | } |
| 240 | |
| 241 | /* |
| 242 | * Call appropriate transform and return -- callback takes care of |
| 243 | * everything else. |
| 244 | */ |
| 245 | error = (*sav->tdb_xform->xf_input)(m, sav, skip, protoff); |
| 246 | KEY_FREESAV(&sav); |
| 247 | splx(s); |
| 248 | return error; |
| 249 | } |
| 250 | |
| 251 | #ifdef INET |
| 252 | /* |
| 253 | * Common input handler for IPv4 AH, ESP, and IPCOMP. |
| 254 | */ |
| 255 | void |
| 256 | ipsec4_common_input(struct mbuf *m, ...) |
| 257 | { |
| 258 | va_list ap; |
| 259 | int off, nxt; |
| 260 | |
| 261 | va_start(ap, m); |
| 262 | off = va_arg(ap, int); |
| 263 | nxt = va_arg(ap, int); |
| 264 | va_end(ap); |
| 265 | |
| 266 | (void) ipsec_common_input(m, off, offsetof(struct ip, ip_p), |
| 267 | AF_INET, nxt); |
| 268 | } |
| 269 | |
| 270 | /* |
| 271 | * IPsec input callback for INET protocols. |
| 272 | * This routine is called as the transform callback. |
| 273 | * Takes care of filtering and other sanity checks on |
| 274 | * the processed packet. |
| 275 | */ |
| 276 | int |
| 277 | ipsec4_common_input_cb(struct mbuf *m, struct secasvar *sav, |
| 278 | int skip, int protoff, struct m_tag *mt) |
| 279 | { |
| 280 | int prot, af __diagused, sproto; |
| 281 | struct ip *ip; |
| 282 | struct m_tag *mtag; |
| 283 | struct tdb_ident *tdbi; |
| 284 | struct secasindex *saidx; |
| 285 | int error; |
| 286 | |
| 287 | IPSEC_SPLASSERT_SOFTNET("ipsec4_common_input_cb" ); |
| 288 | |
| 289 | IPSEC_ASSERT(m != NULL, ("ipsec4_common_input_cb: null mbuf" )); |
| 290 | IPSEC_ASSERT(sav != NULL, ("ipsec4_common_input_cb: null SA" )); |
| 291 | IPSEC_ASSERT(sav->sah != NULL, ("ipsec4_common_input_cb: null SAH" )); |
| 292 | saidx = &sav->sah->saidx; |
| 293 | af = saidx->dst.sa.sa_family; |
| 294 | IPSEC_ASSERT(af == AF_INET, ("ipsec4_common_input_cb: unexpected af %u" ,af)); |
| 295 | sproto = saidx->proto; |
| 296 | IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH || |
| 297 | sproto == IPPROTO_IPCOMP, |
| 298 | ("ipsec4_common_input_cb: unexpected security protocol %u" , |
| 299 | sproto)); |
| 300 | |
| 301 | /* Sanity check */ |
| 302 | if (m == NULL) { |
| 303 | DPRINTF(("ipsec4_common_input_cb: null mbuf" )); |
| 304 | IPSEC_ISTAT(sproto, ESP_STAT_BADKCR, AH_STAT_BADKCR, |
| 305 | IPCOMP_STAT_BADKCR); |
| 306 | KEY_FREESAV(&sav); |
| 307 | return EINVAL; |
| 308 | } |
| 309 | |
| 310 | /* Fix IPv4 header */ |
| 311 | if (m->m_len < skip && (m = m_pullup(m, skip)) == NULL) { |
| 312 | DPRINTF(("ipsec4_common_input_cb: processing failed " |
| 313 | "for SA %s/%08lx\n" , |
| 314 | ipsec_address(&sav->sah->saidx.dst), |
| 315 | (u_long) ntohl(sav->spi))); |
| 316 | IPSEC_ISTAT(sproto, ESP_STAT_HDROPS, AH_STAT_HDROPS, |
| 317 | IPCOMP_STAT_HDROPS); |
| 318 | error = ENOBUFS; |
| 319 | goto bad; |
| 320 | } |
| 321 | |
| 322 | ip = mtod(m, struct ip *); |
| 323 | ip->ip_len = htons(m->m_pkthdr.len); |
| 324 | prot = ip->ip_p; |
| 325 | |
| 326 | /* IP-in-IP encapsulation */ |
| 327 | if (prot == IPPROTO_IPIP) { |
| 328 | struct ip ipn; |
| 329 | |
| 330 | /* ipn will now contain the inner IPv4 header */ |
| 331 | m_copydata(m, ip->ip_hl << 2, sizeof(struct ip), &ipn); |
| 332 | |
| 333 | #ifdef notyet |
| 334 | /* XXX PROXY address isn't recorded in SAH */ |
| 335 | /* |
| 336 | * Check that the inner source address is the same as |
| 337 | * the proxy address, if available. |
| 338 | */ |
| 339 | if ((saidx->proxy.sa.sa_family == AF_INET && |
| 340 | saidx->proxy.sin.sin_addr.s_addr != |
| 341 | INADDR_ANY && |
| 342 | ipn.ip_src.s_addr != |
| 343 | saidx->proxy.sin.sin_addr.s_addr) || |
| 344 | (saidx->proxy.sa.sa_family != AF_INET && |
| 345 | saidx->proxy.sa.sa_family != 0)) { |
| 346 | |
| 347 | DPRINTF(("ipsec4_common_input_cb: inner " |
| 348 | "source address %s doesn't correspond to " |
| 349 | "expected proxy source %s, SA %s/%08lx\n" , |
| 350 | inet_ntoa4(ipn.ip_src), |
| 351 | ipsp_address(saidx->proxy), |
| 352 | ipsp_address(saidx->dst), |
| 353 | (u_long) ntohl(sav->spi))); |
| 354 | |
| 355 | IPSEC_ISTAT(sproto, ESP_STAT_PDROPS, |
| 356 | AH_STAT_PDROPS, |
| 357 | IPCOMP_STAT_PDROPS); |
| 358 | error = EACCES; |
| 359 | goto bad; |
| 360 | } |
| 361 | #endif /*XXX*/ |
| 362 | } |
| 363 | #if INET6 |
| 364 | /* IPv6-in-IP encapsulation. */ |
| 365 | if (prot == IPPROTO_IPV6) { |
| 366 | struct ip6_hdr ip6n; |
| 367 | |
| 368 | /* ip6n will now contain the inner IPv6 header. */ |
| 369 | m_copydata(m, ip->ip_hl << 2, sizeof(struct ip6_hdr), &ip6n); |
| 370 | |
| 371 | #ifdef notyet |
| 372 | /* |
| 373 | * Check that the inner source address is the same as |
| 374 | * the proxy address, if available. |
| 375 | */ |
| 376 | if ((saidx->proxy.sa.sa_family == AF_INET6 && |
| 377 | !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) && |
| 378 | !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src, |
| 379 | &saidx->proxy.sin6.sin6_addr)) || |
| 380 | (saidx->proxy.sa.sa_family != AF_INET6 && |
| 381 | saidx->proxy.sa.sa_family != 0)) { |
| 382 | |
| 383 | DPRINTF(("ipsec4_common_input_cb: inner " |
| 384 | "source address %s doesn't correspond to " |
| 385 | "expected proxy source %s, SA %s/%08lx\n" , |
| 386 | ip6_sprintf(&ip6n.ip6_src), |
| 387 | ipsec_address(&saidx->proxy), |
| 388 | ipsec_address(&saidx->dst), |
| 389 | (u_long) ntohl(sav->spi))); |
| 390 | |
| 391 | IPSEC_ISTAT(sproto, ESP_STAT_PDROPS, |
| 392 | AH_STAT_PDROPS, |
| 393 | IPCOMP_STAT_PDROPS); |
| 394 | error = EACCES; |
| 395 | goto bad; |
| 396 | } |
| 397 | #endif /*XXX*/ |
| 398 | } |
| 399 | #endif /* INET6 */ |
| 400 | |
| 401 | /* |
| 402 | * Record what we've done to the packet (under what SA it was |
| 403 | * processed). If we've been passed an mtag, it means the packet |
| 404 | * was already processed by an ethernet/crypto combo card and |
| 405 | * thus has a tag attached with all the right information, but |
| 406 | * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to |
| 407 | * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type. |
| 408 | */ |
| 409 | if (mt == NULL && sproto != IPPROTO_IPCOMP) { |
| 410 | mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE, |
| 411 | sizeof(struct tdb_ident), M_NOWAIT); |
| 412 | if (mtag == NULL) { |
| 413 | DPRINTF(("ipsec4_common_input_cb: failed to get tag\n" )); |
| 414 | IPSEC_ISTAT(sproto, ESP_STAT_HDROPS, |
| 415 | AH_STAT_HDROPS, IPCOMP_STAT_HDROPS); |
| 416 | error = ENOMEM; |
| 417 | goto bad; |
| 418 | } |
| 419 | |
| 420 | tdbi = (struct tdb_ident *)(mtag + 1); |
| 421 | memcpy(&tdbi->dst, &saidx->dst, saidx->dst.sa.sa_len); |
| 422 | tdbi->proto = sproto; |
| 423 | tdbi->spi = sav->spi; |
| 424 | |
| 425 | m_tag_prepend(m, mtag); |
| 426 | } else { |
| 427 | if (mt != NULL) |
| 428 | mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE; |
| 429 | /* XXX do we need to mark m_flags??? */ |
| 430 | } |
| 431 | |
| 432 | key_sa_recordxfer(sav, m); /* record data transfer */ |
| 433 | |
| 434 | if ((inetsw[ip_protox[prot]].pr_flags & PR_LASTHDR) != 0 && |
| 435 | ipsec4_in_reject(m, NULL)) { |
| 436 | error = EINVAL; |
| 437 | goto bad; |
| 438 | } |
| 439 | (*inetsw[ip_protox[prot]].pr_input)(m, skip, prot); |
| 440 | return 0; |
| 441 | bad: |
| 442 | m_freem(m); |
| 443 | return error; |
| 444 | } |
| 445 | #endif /* INET */ |
| 446 | |
| 447 | #ifdef INET6 |
| 448 | /* IPv6 AH wrapper. */ |
| 449 | int |
| 450 | ipsec6_common_input(struct mbuf **mp, int *offp, int proto) |
| 451 | { |
| 452 | int l = 0; |
| 453 | int protoff, nxt; |
| 454 | struct ip6_ext ip6e; |
| 455 | |
| 456 | if (*offp < sizeof(struct ip6_hdr)) { |
| 457 | DPRINTF(("ipsec6_common_input: bad offset %u\n" , *offp)); |
| 458 | IPSEC_ISTAT(proto, ESP_STAT_HDROPS, AH_STAT_HDROPS, |
| 459 | IPCOMP_STAT_HDROPS); |
| 460 | m_freem(*mp); |
| 461 | return IPPROTO_DONE; |
| 462 | } else if (*offp == sizeof(struct ip6_hdr)) { |
| 463 | protoff = offsetof(struct ip6_hdr, ip6_nxt); |
| 464 | } else { |
| 465 | /* Chase down the header chain... */ |
| 466 | protoff = sizeof(struct ip6_hdr); |
| 467 | nxt = (mtod(*mp, struct ip6_hdr *))->ip6_nxt; |
| 468 | |
| 469 | do { |
| 470 | protoff += l; |
| 471 | m_copydata(*mp, protoff, sizeof(ip6e), &ip6e); |
| 472 | |
| 473 | if (nxt == IPPROTO_AH) |
| 474 | l = (ip6e.ip6e_len + 2) << 2; |
| 475 | else |
| 476 | l = (ip6e.ip6e_len + 1) << 3; |
| 477 | IPSEC_ASSERT(l > 0, |
| 478 | ("ipsec6_common_input: l went zero or negative" )); |
| 479 | |
| 480 | nxt = ip6e.ip6e_nxt; |
| 481 | } while (protoff + l < *offp); |
| 482 | |
| 483 | /* Malformed packet check */ |
| 484 | if (protoff + l != *offp) { |
| 485 | DPRINTF(("ipsec6_common_input: bad packet header chain, " |
| 486 | "protoff %u, l %u, off %u\n" , protoff, l, *offp)); |
| 487 | IPSEC_ISTAT(proto, ESP_STAT_HDROPS, |
| 488 | AH_STAT_HDROPS, |
| 489 | IPCOMP_STAT_HDROPS); |
| 490 | m_freem(*mp); |
| 491 | *mp = NULL; |
| 492 | return IPPROTO_DONE; |
| 493 | } |
| 494 | protoff += offsetof(struct ip6_ext, ip6e_nxt); |
| 495 | } |
| 496 | (void) ipsec_common_input(*mp, *offp, protoff, AF_INET6, proto); |
| 497 | return IPPROTO_DONE; |
| 498 | } |
| 499 | |
| 500 | /* |
| 501 | * NB: ipsec_netbsd.c has a duplicate definition of esp6_ctlinput(), |
| 502 | * with slightly ore recent multicast tests. These should be merged. |
| 503 | * For now, ifdef accordingly. |
| 504 | */ |
| 505 | #ifdef __FreeBSD__ |
| 506 | void |
| 507 | esp6_ctlinput(int cmd, struct sockaddr *sa, void *d) |
| 508 | { |
| 509 | if (sa->sa_family != AF_INET6 || |
| 510 | sa->sa_len != sizeof(struct sockaddr_in6)) |
| 511 | return; |
| 512 | if ((unsigned)cmd >= PRC_NCMDS) |
| 513 | return; |
| 514 | |
| 515 | /* if the parameter is from icmp6, decode it. */ |
| 516 | if (d != NULL) { |
| 517 | struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d; |
| 518 | struct mbuf *m = ip6cp->ip6c_m; |
| 519 | int off = ip6cp->ip6c_off; |
| 520 | |
| 521 | struct ip6ctlparam ip6cp1; |
| 522 | |
| 523 | /* |
| 524 | * Notify the error to all possible sockets via pfctlinput2. |
| 525 | * Since the upper layer information (such as protocol type, |
| 526 | * source and destination ports) is embedded in the encrypted |
| 527 | * data and might have been cut, we can't directly call |
| 528 | * an upper layer ctlinput function. However, the pcbnotify |
| 529 | * function will consider source and destination addresses |
| 530 | * as well as the flow info value, and may be able to find |
| 531 | * some PCB that should be notified. |
| 532 | * Although pfctlinput2 will call esp6_ctlinput(), there is |
| 533 | * no possibility of an infinite loop of function calls, |
| 534 | * because we don't pass the inner IPv6 header. |
| 535 | */ |
| 536 | memset(&ip6cp1, 0, sizeof(ip6cp1)); |
| 537 | ip6cp1.ip6c_src = ip6cp->ip6c_src; |
| 538 | pfctlinput2(cmd, sa, &ip6cp1); |
| 539 | |
| 540 | /* |
| 541 | * Then go to special cases that need ESP header information. |
| 542 | * XXX: We assume that when ip6 is non NULL, |
| 543 | * M and OFF are valid. |
| 544 | */ |
| 545 | |
| 546 | if (cmd == PRC_MSGSIZE) { |
| 547 | struct secasvar *sav; |
| 548 | u_int32_t spi; |
| 549 | int valid; |
| 550 | |
| 551 | /* check header length before using m_copydata */ |
| 552 | if (m->m_pkthdr.len < off + sizeof (struct esp)) |
| 553 | return; |
| 554 | m_copydata(m, off + offsetof(struct esp, esp_spi), |
| 555 | sizeof(u_int32_t), &spi); |
| 556 | /* |
| 557 | * Check to see if we have a valid SA corresponding to |
| 558 | * the address in the ICMP message payload. |
| 559 | */ |
| 560 | sav = KEY_ALLOCSA((union sockaddr_union *)sa, |
| 561 | IPPROTO_ESP, spi); |
| 562 | valid = (sav != NULL); |
| 563 | if (sav) |
| 564 | KEY_FREESAV(&sav); |
| 565 | |
| 566 | /* XXX Further validation? */ |
| 567 | |
| 568 | /* |
| 569 | * Depending on whether the SA is "valid" and |
| 570 | * routing table size (mtudisc_{hi,lo}wat), we will: |
| 571 | * - recalcurate the new MTU and create the |
| 572 | * corresponding routing entry, or |
| 573 | * - ignore the MTU change notification. |
| 574 | */ |
| 575 | icmp6_mtudisc_update(ip6cp, valid); |
| 576 | } |
| 577 | } else { |
| 578 | /* we normally notify any pcb here */ |
| 579 | } |
| 580 | } |
| 581 | #endif /* __FreeBSD__ */ |
| 582 | |
| 583 | extern const struct ip6protosw inet6sw[]; |
| 584 | extern u_char ip6_protox[]; |
| 585 | |
| 586 | /* |
| 587 | * IPsec input callback, called by the transform callback. Takes care of |
| 588 | * filtering and other sanity checks on the processed packet. |
| 589 | */ |
| 590 | int |
| 591 | ipsec6_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip, int protoff, |
| 592 | struct m_tag *mt) |
| 593 | { |
| 594 | int af __diagused, sproto; |
| 595 | struct ip6_hdr *ip6; |
| 596 | struct m_tag *mtag; |
| 597 | struct tdb_ident *tdbi; |
| 598 | struct secasindex *saidx; |
| 599 | int nxt; |
| 600 | u_int8_t prot, nxt8; |
| 601 | int error, nest; |
| 602 | |
| 603 | IPSEC_ASSERT(m != NULL, ("ipsec6_common_input_cb: null mbuf" )); |
| 604 | IPSEC_ASSERT(sav != NULL, ("ipsec6_common_input_cb: null SA" )); |
| 605 | IPSEC_ASSERT(sav->sah != NULL, ("ipsec6_common_input_cb: null SAH" )); |
| 606 | saidx = &sav->sah->saidx; |
| 607 | af = saidx->dst.sa.sa_family; |
| 608 | IPSEC_ASSERT(af == AF_INET6, |
| 609 | ("ipsec6_common_input_cb: unexpected af %u" , af)); |
| 610 | sproto = saidx->proto; |
| 611 | IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH || |
| 612 | sproto == IPPROTO_IPCOMP, |
| 613 | ("ipsec6_common_input_cb: unexpected security protocol %u" , |
| 614 | sproto)); |
| 615 | |
| 616 | /* Sanity check */ |
| 617 | if (m == NULL) { |
| 618 | DPRINTF(("ipsec6_common_input_cb: null mbuf" )); |
| 619 | IPSEC_ISTAT(sproto, ESP_STAT_BADKCR, AH_STAT_BADKCR, |
| 620 | IPCOMP_STAT_BADKCR); |
| 621 | error = EINVAL; |
| 622 | goto bad; |
| 623 | } |
| 624 | |
| 625 | /* Fix IPv6 header */ |
| 626 | if (m->m_len < sizeof(struct ip6_hdr) && |
| 627 | (m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) { |
| 628 | |
| 629 | DPRINTF(("ipsec6_common_input_cb: processing failed " |
| 630 | "for SA %s/%08lx\n" , ipsec_address(&sav->sah->saidx.dst), |
| 631 | (u_long) ntohl(sav->spi))); |
| 632 | |
| 633 | IPSEC_ISTAT(sproto, ESP_STAT_HDROPS, AH_STAT_HDROPS, |
| 634 | IPCOMP_STAT_HDROPS); |
| 635 | error = EACCES; |
| 636 | goto bad; |
| 637 | } |
| 638 | |
| 639 | ip6 = mtod(m, struct ip6_hdr *); |
| 640 | ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); |
| 641 | |
| 642 | /* Save protocol */ |
| 643 | m_copydata(m, protoff, 1, &prot); |
| 644 | |
| 645 | #ifdef INET |
| 646 | /* IP-in-IP encapsulation */ |
| 647 | if (prot == IPPROTO_IPIP) { |
| 648 | struct ip ipn; |
| 649 | |
| 650 | /* ipn will now contain the inner IPv4 header */ |
| 651 | m_copydata(m, skip, sizeof(struct ip), &ipn); |
| 652 | |
| 653 | #ifdef notyet |
| 654 | /* |
| 655 | * Check that the inner source address is the same as |
| 656 | * the proxy address, if available. |
| 657 | */ |
| 658 | if ((saidx->proxy.sa.sa_family == AF_INET && |
| 659 | saidx->proxy.sin.sin_addr.s_addr != INADDR_ANY && |
| 660 | ipn.ip_src.s_addr != saidx->proxy.sin.sin_addr.s_addr) || |
| 661 | (saidx->proxy.sa.sa_family != AF_INET && |
| 662 | saidx->proxy.sa.sa_family != 0)) { |
| 663 | |
| 664 | DPRINTF(("ipsec6_common_input_cb: inner " |
| 665 | "source address %s doesn't correspond to " |
| 666 | "expected proxy source %s, SA %s/%08lx\n" , |
| 667 | inet_ntoa4(ipn.ip_src), |
| 668 | ipsec_address(&saidx->proxy), |
| 669 | ipsec_address(&saidx->dst), |
| 670 | (u_long) ntohl(sav->spi))); |
| 671 | |
| 672 | IPSEC_ISTAT(sproto, ESP_STAT_PDROPS, |
| 673 | AH_STAT_PDROPS, IPCOMP_STAT_PDROPS); |
| 674 | error = EACCES; |
| 675 | goto bad; |
| 676 | } |
| 677 | #endif /*XXX*/ |
| 678 | } |
| 679 | #endif /* INET */ |
| 680 | |
| 681 | /* IPv6-in-IP encapsulation */ |
| 682 | if (prot == IPPROTO_IPV6) { |
| 683 | struct ip6_hdr ip6n; |
| 684 | |
| 685 | /* ip6n will now contain the inner IPv6 header. */ |
| 686 | m_copydata(m, skip, sizeof(struct ip6_hdr), &ip6n); |
| 687 | |
| 688 | #ifdef notyet |
| 689 | /* |
| 690 | * Check that the inner source address is the same as |
| 691 | * the proxy address, if available. |
| 692 | */ |
| 693 | if ((saidx->proxy.sa.sa_family == AF_INET6 && |
| 694 | !IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) && |
| 695 | !IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src, |
| 696 | &saidx->proxy.sin6.sin6_addr)) || |
| 697 | (saidx->proxy.sa.sa_family != AF_INET6 && |
| 698 | saidx->proxy.sa.sa_family != 0)) { |
| 699 | |
| 700 | DPRINTF(("ipsec6_common_input_cb: inner " |
| 701 | "source address %s doesn't correspond to " |
| 702 | "expected proxy source %s, SA %s/%08lx\n" , |
| 703 | ip6_sprintf(&ip6n.ip6_src), |
| 704 | ipsec_address(&saidx->proxy), |
| 705 | ipsec_address(&saidx->dst), |
| 706 | (u_long) ntohl(sav->spi))); |
| 707 | |
| 708 | IPSEC_ISTAT(sproto, ESP_STAT_PDROPS, |
| 709 | AH_STAT_PDROPS, IPCOMP_STAT_PDROPS); |
| 710 | error = EACCES; |
| 711 | goto bad; |
| 712 | } |
| 713 | #endif /*XXX*/ |
| 714 | } |
| 715 | |
| 716 | /* |
| 717 | * Record what we've done to the packet (under what SA it was |
| 718 | * processed). If we've been passed an mtag, it means the packet |
| 719 | * was already processed by an ethernet/crypto combo card and |
| 720 | * thus has a tag attached with all the right information, but |
| 721 | * with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to |
| 722 | * PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type. |
| 723 | */ |
| 724 | if (mt == NULL && sproto != IPPROTO_IPCOMP) { |
| 725 | mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE, |
| 726 | sizeof(struct tdb_ident), M_NOWAIT); |
| 727 | if (mtag == NULL) { |
| 728 | DPRINTF(("ipsec_common_input_cb: failed to " |
| 729 | "get tag\n" )); |
| 730 | IPSEC_ISTAT(sproto, ESP_STAT_HDROPS, |
| 731 | AH_STAT_HDROPS, IPCOMP_STAT_HDROPS); |
| 732 | error = ENOMEM; |
| 733 | goto bad; |
| 734 | } |
| 735 | |
| 736 | tdbi = (struct tdb_ident *)(mtag + 1); |
| 737 | memcpy(&tdbi->dst, &saidx->dst, sizeof(union sockaddr_union)); |
| 738 | tdbi->proto = sproto; |
| 739 | tdbi->spi = sav->spi; |
| 740 | |
| 741 | m_tag_prepend(m, mtag); |
| 742 | } else { |
| 743 | if (mt != NULL) |
| 744 | mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE; |
| 745 | /* XXX do we need to mark m_flags??? */ |
| 746 | } |
| 747 | |
| 748 | key_sa_recordxfer(sav, m); |
| 749 | |
| 750 | /* Retrieve new protocol */ |
| 751 | m_copydata(m, protoff, sizeof(u_int8_t), &nxt8); |
| 752 | |
| 753 | /* |
| 754 | * See the end of ip6_input for this logic. |
| 755 | * IPPROTO_IPV[46] case will be processed just like other ones |
| 756 | */ |
| 757 | nest = 0; |
| 758 | nxt = nxt8; |
| 759 | while (nxt != IPPROTO_DONE) { |
| 760 | if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) { |
| 761 | IP6_STATINC(IP6_STAT_TOOMANYHDR); |
| 762 | error = EINVAL; |
| 763 | goto bad; |
| 764 | } |
| 765 | |
| 766 | /* |
| 767 | * Protection against faulty packet - there should be |
| 768 | * more sanity checks in header chain processing. |
| 769 | */ |
| 770 | if (m->m_pkthdr.len < skip) { |
| 771 | IP6_STATINC(IP6_STAT_TOOSHORT); |
| 772 | in6_ifstat_inc(m_get_rcvif_NOMPSAFE(m), |
| 773 | ifs6_in_truncated); |
| 774 | error = EINVAL; |
| 775 | goto bad; |
| 776 | } |
| 777 | /* |
| 778 | * Enforce IPsec policy checking if we are seeing last header. |
| 779 | * note that we do not visit this with protocols with pcb layer |
| 780 | * code - like udp/tcp/raw ip. |
| 781 | */ |
| 782 | if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 && |
| 783 | ipsec6_in_reject(m, NULL)) { |
| 784 | error = EINVAL; |
| 785 | goto bad; |
| 786 | } |
| 787 | nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &skip, nxt); |
| 788 | } |
| 789 | return 0; |
| 790 | bad: |
| 791 | if (m) |
| 792 | m_freem(m); |
| 793 | return error; |
| 794 | } |
| 795 | #endif /* INET6 */ |
| 796 | |