1 /* $FreeBSD$ */ 2 /* $OpenBSD: ip_ipcomp.c,v 1.1 2001/07/05 12:08:52 jjbg Exp $ */ 3 4 /*- 5 * Copyright (c) 2001 Jean-Jacques Bernard-Gundol (jj@wabbitt.org) 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 /* IP payload compression protocol (IPComp), see RFC 2393 */ 32 #include "opt_inet.h" 33 #include "opt_inet6.h" 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/mbuf.h> 38 #include <sys/lock.h> 39 #include <sys/mutex.h> 40 #include <sys/socket.h> 41 #include <sys/kernel.h> 42 #include <sys/protosw.h> 43 #include <sys/sysctl.h> 44 45 #include <netinet/in.h> 46 #include <netinet/in_systm.h> 47 #include <netinet/ip.h> 48 #include <netinet/ip_var.h> 49 50 #include <net/route.h> 51 #include <netipsec/ipsec.h> 52 #include <netipsec/xform.h> 53 54 #ifdef INET6 55 #include <netinet/ip6.h> 56 #include <netipsec/ipsec6.h> 57 #endif 58 59 #include <netipsec/ipcomp.h> 60 #include <netipsec/ipcomp_var.h> 61 62 #include <netipsec/key.h> 63 #include <netipsec/key_debug.h> 64 65 #include <opencrypto/cryptodev.h> 66 #include <opencrypto/deflate.h> 67 #include <opencrypto/xform.h> 68 69 int ipcomp_enable = 0; 70 struct ipcompstat ipcompstat; 71 72 SYSCTL_DECL(_net_inet_ipcomp); 73 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO, 74 ipcomp_enable, CTLFLAG_RW, &ipcomp_enable, 0, ""); 75 SYSCTL_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS, 76 stats, CTLFLAG_RD, &ipcompstat, ipcompstat, ""); 77 78 static int ipcomp_input_cb(struct cryptop *crp); 79 static int ipcomp_output_cb(struct cryptop *crp); 80 81 struct comp_algo * 82 ipcomp_algorithm_lookup(int alg) 83 { 84 if (alg >= IPCOMP_ALG_MAX) 85 return NULL; 86 switch (alg) { 87 case SADB_X_CALG_DEFLATE: 88 return &comp_algo_deflate; 89 } 90 return NULL; 91 } 92 93 /* 94 * ipcomp_init() is called when an CPI is being set up. 95 */ 96 static int 97 ipcomp_init(struct secasvar *sav, struct xformsw *xsp) 98 { 99 struct comp_algo *tcomp; 100 struct cryptoini cric; 101 102 /* NB: algorithm really comes in alg_enc and not alg_comp! */ 103 tcomp = ipcomp_algorithm_lookup(sav->alg_enc); 104 if (tcomp == NULL) { 105 DPRINTF(("%s: unsupported compression algorithm %d\n", __func__, 106 sav->alg_comp)); 107 return EINVAL; 108 } 109 sav->alg_comp = sav->alg_enc; /* set for doing histogram */ 110 sav->tdb_xform = xsp; 111 sav->tdb_compalgxform = tcomp; 112 113 /* Initialize crypto session */ 114 bzero(&cric, sizeof (cric)); 115 cric.cri_alg = sav->tdb_compalgxform->type; 116 117 return crypto_newsession(&sav->tdb_cryptoid, &cric, crypto_support); 118 } 119 120 /* 121 * ipcomp_zeroize() used when IPCA is deleted 122 */ 123 static int 124 ipcomp_zeroize(struct secasvar *sav) 125 { 126 int err; 127 128 err = crypto_freesession(sav->tdb_cryptoid); 129 sav->tdb_cryptoid = 0; 130 return err; 131 } 132 133 /* 134 * ipcomp_input() gets called to uncompress an input packet 135 */ 136 static int 137 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) 138 { 139 struct tdb_crypto *tc; 140 struct cryptodesc *crdc; 141 struct cryptop *crp; 142 int hlen = IPCOMP_HLENGTH; 143 144 IPSEC_SPLASSERT_SOFTNET(__func__); 145 146 /* Get crypto descriptors */ 147 crp = crypto_getreq(1); 148 if (crp == NULL) { 149 m_freem(m); 150 DPRINTF(("%s: no crypto descriptors\n", __func__)); 151 ipcompstat.ipcomps_crypto++; 152 return ENOBUFS; 153 } 154 /* Get IPsec-specific opaque pointer */ 155 tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO); 156 if (tc == NULL) { 157 m_freem(m); 158 crypto_freereq(crp); 159 DPRINTF(("%s: cannot allocate tdb_crypto\n", __func__)); 160 ipcompstat.ipcomps_crypto++; 161 return ENOBUFS; 162 } 163 crdc = crp->crp_desc; 164 165 crdc->crd_skip = skip + hlen; 166 crdc->crd_len = m->m_pkthdr.len - (skip + hlen); 167 crdc->crd_inject = skip; 168 169 tc->tc_ptr = 0; 170 171 /* Decompression operation */ 172 crdc->crd_alg = sav->tdb_compalgxform->type; 173 174 /* Crypto operation descriptor */ 175 crp->crp_ilen = m->m_pkthdr.len - (skip + hlen); 176 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC; 177 crp->crp_buf = (caddr_t) m; 178 crp->crp_callback = ipcomp_input_cb; 179 crp->crp_sid = sav->tdb_cryptoid; 180 crp->crp_opaque = (caddr_t) tc; 181 182 /* These are passed as-is to the callback */ 183 tc->tc_spi = sav->spi; 184 tc->tc_dst = sav->sah->saidx.dst; 185 tc->tc_proto = sav->sah->saidx.proto; 186 tc->tc_protoff = protoff; 187 tc->tc_skip = skip; 188 189 return crypto_dispatch(crp); 190 } 191 192 #ifdef INET6 193 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do { \ 194 if (saidx->dst.sa.sa_family == AF_INET6) { \ 195 error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \ 196 } else { \ 197 error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \ 198 } \ 199 } while (0) 200 #else 201 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) \ 202 (error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag)) 203 #endif 204 205 /* 206 * IPComp input callback from the crypto driver. 207 */ 208 static int 209 ipcomp_input_cb(struct cryptop *crp) 210 { 211 struct cryptodesc *crd; 212 struct tdb_crypto *tc; 213 int skip, protoff; 214 struct mtag *mtag; 215 struct mbuf *m; 216 struct secasvar *sav; 217 struct secasindex *saidx; 218 int hlen = IPCOMP_HLENGTH, error, clen; 219 u_int8_t nproto; 220 caddr_t addr; 221 222 NET_LOCK_GIANT(); 223 224 crd = crp->crp_desc; 225 226 tc = (struct tdb_crypto *) crp->crp_opaque; 227 IPSEC_ASSERT(tc != NULL, ("null opaque crypto data area!")); 228 skip = tc->tc_skip; 229 protoff = tc->tc_protoff; 230 mtag = (struct mtag *) tc->tc_ptr; 231 m = (struct mbuf *) crp->crp_buf; 232 233 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi); 234 if (sav == NULL) { 235 ipcompstat.ipcomps_notdb++; 236 DPRINTF(("%s: SA expired while in crypto\n", __func__)); 237 error = ENOBUFS; /*XXX*/ 238 goto bad; 239 } 240 241 saidx = &sav->sah->saidx; 242 IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET || 243 saidx->dst.sa.sa_family == AF_INET6, 244 ("unexpected protocol family %u", saidx->dst.sa.sa_family)); 245 246 /* Check for crypto errors */ 247 if (crp->crp_etype) { 248 /* Reset the session ID */ 249 if (sav->tdb_cryptoid != 0) 250 sav->tdb_cryptoid = crp->crp_sid; 251 252 if (crp->crp_etype == EAGAIN) { 253 KEY_FREESAV(&sav); 254 error = crypto_dispatch(crp); 255 NET_UNLOCK_GIANT(); 256 return error; 257 } 258 259 ipcompstat.ipcomps_noxform++; 260 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype)); 261 error = crp->crp_etype; 262 goto bad; 263 } 264 /* Shouldn't happen... */ 265 if (m == NULL) { 266 ipcompstat.ipcomps_crypto++; 267 DPRINTF(("%s: null mbuf returned from crypto\n", __func__)); 268 error = EINVAL; 269 goto bad; 270 } 271 ipcompstat.ipcomps_hist[sav->alg_comp]++; 272 273 clen = crp->crp_olen; /* Length of data after processing */ 274 275 /* Release the crypto descriptors */ 276 free(tc, M_XDATA), tc = NULL; 277 crypto_freereq(crp), crp = NULL; 278 279 /* In case it's not done already, adjust the size of the mbuf chain */ 280 m->m_pkthdr.len = clen + hlen + skip; 281 282 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) { 283 ipcompstat.ipcomps_hdrops++; /*XXX*/ 284 DPRINTF(("%s: m_pullup failed\n", __func__)); 285 error = EINVAL; /*XXX*/ 286 goto bad; 287 } 288 289 /* Keep the next protocol field */ 290 addr = (caddr_t) mtod(m, struct ip *) + skip; 291 nproto = ((struct ipcomp *) addr)->comp_nxt; 292 293 /* Remove the IPCOMP header */ 294 error = m_striphdr(m, skip, hlen); 295 if (error) { 296 ipcompstat.ipcomps_hdrops++; 297 DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__, 298 ipsec_address(&sav->sah->saidx.dst), 299 (u_long) ntohl(sav->spi))); 300 goto bad; 301 } 302 303 /* Restore the Next Protocol field */ 304 m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto); 305 306 IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, NULL); 307 308 KEY_FREESAV(&sav); 309 NET_UNLOCK_GIANT(); 310 return error; 311 bad: 312 if (sav) 313 KEY_FREESAV(&sav); 314 if (m) 315 m_freem(m); 316 if (tc != NULL) 317 free(tc, M_XDATA); 318 if (crp) 319 crypto_freereq(crp); 320 NET_UNLOCK_GIANT(); 321 return error; 322 } 323 324 /* 325 * IPComp output routine, called by ipsec[46]_process_packet() 326 */ 327 static int 328 ipcomp_output( 329 struct mbuf *m, 330 struct ipsecrequest *isr, 331 struct mbuf **mp, 332 int skip, 333 int protoff 334 ) 335 { 336 struct secasvar *sav; 337 struct comp_algo *ipcompx; 338 int error, ralen, hlen, maxpacketsize, roff; 339 u_int8_t prot; 340 struct cryptodesc *crdc; 341 struct cryptop *crp; 342 struct tdb_crypto *tc; 343 struct mbuf *mo; 344 struct ipcomp *ipcomp; 345 346 IPSEC_SPLASSERT_SOFTNET(__func__); 347 348 sav = isr->sav; 349 IPSEC_ASSERT(sav != NULL, ("null SA")); 350 ipcompx = sav->tdb_compalgxform; 351 IPSEC_ASSERT(ipcompx != NULL, ("null compression xform")); 352 353 ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */ 354 hlen = IPCOMP_HLENGTH; 355 356 ipcompstat.ipcomps_output++; 357 358 /* Check for maximum packet size violations. */ 359 switch (sav->sah->saidx.dst.sa.sa_family) { 360 #ifdef INET 361 case AF_INET: 362 maxpacketsize = IP_MAXPACKET; 363 break; 364 #endif /* INET */ 365 #ifdef INET6 366 case AF_INET6: 367 maxpacketsize = IPV6_MAXPACKET; 368 break; 369 #endif /* INET6 */ 370 default: 371 ipcompstat.ipcomps_nopf++; 372 DPRINTF(("%s: unknown/unsupported protocol family %d, " 373 "IPCA %s/%08lx\n", __func__, 374 sav->sah->saidx.dst.sa.sa_family, 375 ipsec_address(&sav->sah->saidx.dst), 376 (u_long) ntohl(sav->spi))); 377 error = EPFNOSUPPORT; 378 goto bad; 379 } 380 if (skip + hlen + ralen > maxpacketsize) { 381 ipcompstat.ipcomps_toobig++; 382 DPRINTF(("%s: packet in IPCA %s/%08lx got too big " 383 "(len %u, max len %u)\n", __func__, 384 ipsec_address(&sav->sah->saidx.dst), 385 (u_long) ntohl(sav->spi), 386 skip + hlen + ralen, maxpacketsize)); 387 error = EMSGSIZE; 388 goto bad; 389 } 390 391 /* Update the counters */ 392 ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip; 393 394 m = m_unshare(m, M_NOWAIT); 395 if (m == NULL) { 396 ipcompstat.ipcomps_hdrops++; 397 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n", 398 __func__, ipsec_address(&sav->sah->saidx.dst), 399 (u_long) ntohl(sav->spi))); 400 error = ENOBUFS; 401 goto bad; 402 } 403 404 /* Inject IPCOMP header */ 405 mo = m_makespace(m, skip, hlen, &roff); 406 if (mo == NULL) { 407 ipcompstat.ipcomps_wrap++; 408 DPRINTF(("%s: IPCOMP header inject failed for IPCA %s/%08lx\n", 409 __func__, ipsec_address(&sav->sah->saidx.dst), 410 (u_long) ntohl(sav->spi))); 411 error = ENOBUFS; 412 goto bad; 413 } 414 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff); 415 416 /* Initialize the IPCOMP header */ 417 /* XXX alignment always correct? */ 418 switch (sav->sah->saidx.dst.sa.sa_family) { 419 #ifdef INET 420 case AF_INET: 421 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p; 422 break; 423 #endif /* INET */ 424 #ifdef INET6 425 case AF_INET6: 426 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt; 427 break; 428 #endif 429 } 430 ipcomp->comp_flags = 0; 431 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi)); 432 433 /* Fix Next Protocol in IPv4/IPv6 header */ 434 prot = IPPROTO_IPCOMP; 435 m_copyback(m, protoff, sizeof(u_int8_t), (u_char *) &prot); 436 437 /* Ok now, we can pass to the crypto processing */ 438 439 /* Get crypto descriptors */ 440 crp = crypto_getreq(1); 441 if (crp == NULL) { 442 ipcompstat.ipcomps_crypto++; 443 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__)); 444 error = ENOBUFS; 445 goto bad; 446 } 447 crdc = crp->crp_desc; 448 449 /* Compression descriptor */ 450 crdc->crd_skip = skip + hlen; 451 crdc->crd_len = m->m_pkthdr.len - (skip + hlen); 452 crdc->crd_flags = CRD_F_COMP; 453 crdc->crd_inject = skip + hlen; 454 455 /* Compression operation */ 456 crdc->crd_alg = ipcompx->type; 457 458 /* IPsec-specific opaque crypto info */ 459 tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto), 460 M_XDATA, M_NOWAIT|M_ZERO); 461 if (tc == NULL) { 462 ipcompstat.ipcomps_crypto++; 463 DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__)); 464 crypto_freereq(crp); 465 error = ENOBUFS; 466 goto bad; 467 } 468 469 tc->tc_isr = isr; 470 tc->tc_spi = sav->spi; 471 tc->tc_dst = sav->sah->saidx.dst; 472 tc->tc_proto = sav->sah->saidx.proto; 473 tc->tc_skip = skip + hlen; 474 475 /* Crypto operation descriptor */ 476 crp->crp_ilen = m->m_pkthdr.len; /* Total input length */ 477 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC; 478 crp->crp_buf = (caddr_t) m; 479 crp->crp_callback = ipcomp_output_cb; 480 crp->crp_opaque = (caddr_t) tc; 481 crp->crp_sid = sav->tdb_cryptoid; 482 483 return crypto_dispatch(crp); 484 bad: 485 if (m) 486 m_freem(m); 487 return (error); 488 } 489 490 /* 491 * IPComp output callback from the crypto driver. 492 */ 493 static int 494 ipcomp_output_cb(struct cryptop *crp) 495 { 496 struct tdb_crypto *tc; 497 struct ipsecrequest *isr; 498 struct secasvar *sav; 499 struct mbuf *m; 500 int error, skip, rlen; 501 502 NET_LOCK_GIANT(); 503 504 tc = (struct tdb_crypto *) crp->crp_opaque; 505 IPSEC_ASSERT(tc != NULL, ("null opaque data area!")); 506 m = (struct mbuf *) crp->crp_buf; 507 skip = tc->tc_skip; 508 rlen = crp->crp_ilen - skip; 509 510 isr = tc->tc_isr; 511 IPSECREQUEST_LOCK(isr); 512 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi); 513 if (sav == NULL) { 514 ipcompstat.ipcomps_notdb++; 515 DPRINTF(("%s: SA expired while in crypto\n", __func__)); 516 error = ENOBUFS; /*XXX*/ 517 goto bad; 518 } 519 IPSEC_ASSERT(isr->sav == sav, ("SA changed\n")); 520 521 /* Check for crypto errors */ 522 if (crp->crp_etype) { 523 /* Reset session ID */ 524 if (sav->tdb_cryptoid != 0) 525 sav->tdb_cryptoid = crp->crp_sid; 526 527 if (crp->crp_etype == EAGAIN) { 528 KEY_FREESAV(&sav); 529 IPSECREQUEST_UNLOCK(isr); 530 error = crypto_dispatch(crp); 531 NET_UNLOCK_GIANT(); 532 return error; 533 } 534 ipcompstat.ipcomps_noxform++; 535 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype)); 536 error = crp->crp_etype; 537 goto bad; 538 } 539 /* Shouldn't happen... */ 540 if (m == NULL) { 541 ipcompstat.ipcomps_crypto++; 542 DPRINTF(("%s: bogus return buffer from crypto\n", __func__)); 543 error = EINVAL; 544 goto bad; 545 } 546 ipcompstat.ipcomps_hist[sav->alg_comp]++; 547 548 if (rlen > crp->crp_olen) { 549 /* Adjust the length in the IP header */ 550 switch (sav->sah->saidx.dst.sa.sa_family) { 551 #ifdef INET 552 case AF_INET: 553 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 554 break; 555 #endif /* INET */ 556 #ifdef INET6 557 case AF_INET6: 558 mtod(m, struct ip6_hdr *)->ip6_plen = 559 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr); 560 break; 561 #endif /* INET6 */ 562 default: 563 ipcompstat.ipcomps_nopf++; 564 DPRINTF(("%s: unknown/unsupported protocol " 565 "family %d, IPCA %s/%08lx\n", __func__, 566 sav->sah->saidx.dst.sa.sa_family, 567 ipsec_address(&sav->sah->saidx.dst), 568 (u_long) ntohl(sav->spi))); 569 error = EPFNOSUPPORT; 570 goto bad; 571 } 572 } else { 573 /* compression was useless, we have lost time */ 574 /* XXX add statistic */ 575 } 576 577 /* Release the crypto descriptor */ 578 free(tc, M_XDATA); 579 crypto_freereq(crp); 580 581 /* NB: m is reclaimed by ipsec_process_done. */ 582 error = ipsec_process_done(m, isr); 583 KEY_FREESAV(&sav); 584 IPSECREQUEST_UNLOCK(isr); 585 NET_UNLOCK_GIANT(); 586 return error; 587 bad: 588 if (sav) 589 KEY_FREESAV(&sav); 590 IPSECREQUEST_UNLOCK(isr); 591 if (m) 592 m_freem(m); 593 free(tc, M_XDATA); 594 crypto_freereq(crp); 595 NET_UNLOCK_GIANT(); 596 return error; 597 } 598 599 static struct xformsw ipcomp_xformsw = { 600 XF_IPCOMP, XFT_COMP, "IPcomp", 601 ipcomp_init, ipcomp_zeroize, ipcomp_input, 602 ipcomp_output 603 }; 604 605 static void 606 ipcomp_attach(void) 607 { 608 xform_register(&ipcomp_xformsw); 609 } 610 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipcomp_attach, NULL); 611