xform_ipcomp.c revision 119643
1/* $FreeBSD: head/sys/netipsec/xform_ipcomp.c 119643 2003-09-01 05:35:55Z sam $ */ 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 69int ipcomp_enable = 0; 70struct ipcompstat ipcompstat; 71 72SYSCTL_DECL(_net_inet_ipcomp); 73SYSCTL_INT(_net_inet_ipcomp, OID_AUTO, 74 ipcomp_enable, CTLFLAG_RW, &ipcomp_enable, 0, ""); 75SYSCTL_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS, 76 stats, CTLFLAG_RD, &ipcompstat, ipcompstat, ""); 77 78static int ipcomp_input_cb(struct cryptop *crp); 79static int ipcomp_output_cb(struct cryptop *crp); 80 81struct comp_algo * 82ipcomp_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 */ 96static int 97ipcomp_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(("ipcomp_init: unsupported compression algorithm %d\n", 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 */ 123static int 124ipcomp_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 */ 136static int 137ipcomp_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#if 0 145 SPLASSERT(net, "ipcomp_input"); 146#endif 147 148 /* Get crypto descriptors */ 149 crp = crypto_getreq(1); 150 if (crp == NULL) { 151 m_freem(m); 152 DPRINTF(("ipcomp_input: no crypto descriptors\n")); 153 ipcompstat.ipcomps_crypto++; 154 return ENOBUFS; 155 } 156 /* Get IPsec-specific opaque pointer */ 157 tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO); 158 if (tc == NULL) { 159 m_freem(m); 160 crypto_freereq(crp); 161 DPRINTF(("ipcomp_input: cannot allocate tdb_crypto\n")); 162 ipcompstat.ipcomps_crypto++; 163 return ENOBUFS; 164 } 165 crdc = crp->crp_desc; 166 167 crdc->crd_skip = skip + hlen; 168 crdc->crd_len = m->m_pkthdr.len - (skip + hlen); 169 crdc->crd_inject = skip; 170 171 tc->tc_ptr = 0; 172 173 /* Decompression operation */ 174 crdc->crd_alg = sav->tdb_compalgxform->type; 175 176 /* Crypto operation descriptor */ 177 crp->crp_ilen = m->m_pkthdr.len - (skip + hlen); 178 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC; 179 crp->crp_buf = (caddr_t) m; 180 crp->crp_callback = ipcomp_input_cb; 181 crp->crp_sid = sav->tdb_cryptoid; 182 crp->crp_opaque = (caddr_t) tc; 183 184 /* These are passed as-is to the callback */ 185 tc->tc_spi = sav->spi; 186 tc->tc_dst = sav->sah->saidx.dst; 187 tc->tc_proto = sav->sah->saidx.proto; 188 tc->tc_protoff = protoff; 189 tc->tc_skip = skip; 190 191 return crypto_dispatch(crp); 192} 193 194#ifdef INET6 195#define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do { \ 196 if (saidx->dst.sa.sa_family == AF_INET6) { \ 197 error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \ 198 } else { \ 199 error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \ 200 } \ 201} while (0) 202#else 203#define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) \ 204 (error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag)) 205#endif 206 207/* 208 * IPComp input callback from the crypto driver. 209 */ 210static int 211ipcomp_input_cb(struct cryptop *crp) 212{ 213 struct cryptodesc *crd; 214 struct tdb_crypto *tc; 215 int skip, protoff; 216 struct mtag *mtag; 217 struct mbuf *m; 218 struct secasvar *sav; 219 struct secasindex *saidx; 220 int hlen = IPCOMP_HLENGTH, error, clen; 221 u_int8_t nproto; 222 caddr_t addr; 223 224 crd = crp->crp_desc; 225 226 tc = (struct tdb_crypto *) crp->crp_opaque; 227 KASSERT(tc != NULL, ("ipcomp_input_cb: 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(("ipcomp_input_cb: SA expired while in crypto\n")); 237 error = ENOBUFS; /*XXX*/ 238 goto bad; 239 } 240 241 saidx = &sav->sah->saidx; 242 KASSERT(saidx->dst.sa.sa_family == AF_INET || 243 saidx->dst.sa.sa_family == AF_INET6, 244 ("ah_input_cb: unexpected protocol family %u", 245 saidx->dst.sa.sa_family)); 246 247 /* Check for crypto errors */ 248 if (crp->crp_etype) { 249 /* Reset the session ID */ 250 if (sav->tdb_cryptoid != 0) 251 sav->tdb_cryptoid = crp->crp_sid; 252 253 if (crp->crp_etype == EAGAIN) { 254 KEY_FREESAV(&sav); 255 return crypto_dispatch(crp); 256 } 257 258 ipcompstat.ipcomps_noxform++; 259 DPRINTF(("ipcomp_input_cb: crypto error %d\n", crp->crp_etype)); 260 error = crp->crp_etype; 261 goto bad; 262 } 263 /* Shouldn't happen... */ 264 if (m == NULL) { 265 ipcompstat.ipcomps_crypto++; 266 DPRINTF(("ipcomp_input_cb: null mbuf returned from crypto\n")); 267 error = EINVAL; 268 goto bad; 269 } 270 ipcompstat.ipcomps_hist[sav->alg_comp]++; 271 272 clen = crp->crp_olen; /* Length of data after processing */ 273 274 /* Release the crypto descriptors */ 275 free(tc, M_XDATA), tc = NULL; 276 crypto_freereq(crp), crp = NULL; 277 278 /* In case it's not done already, adjust the size of the mbuf chain */ 279 m->m_pkthdr.len = clen + hlen + skip; 280 281 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) { 282 ipcompstat.ipcomps_hdrops++; /*XXX*/ 283 DPRINTF(("ipcomp_input_cb: m_pullup failed\n")); 284 error = EINVAL; /*XXX*/ 285 goto bad; 286 } 287 288 /* Keep the next protocol field */ 289 addr = (caddr_t) mtod(m, struct ip *) + skip; 290 nproto = ((struct ipcomp *) addr)->comp_nxt; 291 292 /* Remove the IPCOMP header */ 293 error = m_striphdr(m, skip, hlen); 294 if (error) { 295 ipcompstat.ipcomps_hdrops++; 296 DPRINTF(("ipcomp_input_cb: bad mbuf chain, IPCA %s/%08lx\n", 297 ipsec_address(&sav->sah->saidx.dst), 298 (u_long) ntohl(sav->spi))); 299 goto bad; 300 } 301 302 /* Restore the Next Protocol field */ 303 m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto); 304 305 IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, NULL); 306 307 KEY_FREESAV(&sav); 308 return error; 309bad: 310 if (sav) 311 KEY_FREESAV(&sav); 312 if (m) 313 m_freem(m); 314 if (tc != NULL) 315 free(tc, M_XDATA); 316 if (crp) 317 crypto_freereq(crp); 318 return error; 319} 320 321/* 322 * IPComp output routine, called by ipsec[46]_process_packet() 323 */ 324static int 325ipcomp_output( 326 struct mbuf *m, 327 struct ipsecrequest *isr, 328 struct mbuf **mp, 329 int skip, 330 int protoff 331) 332{ 333 struct secasvar *sav; 334 struct comp_algo *ipcompx; 335 int error, ralen, hlen, maxpacketsize, roff; 336 u_int8_t prot; 337 struct cryptodesc *crdc; 338 struct cryptop *crp; 339 struct tdb_crypto *tc; 340 struct mbuf *mo; 341 struct ipcomp *ipcomp; 342 343#if 0 344 SPLASSERT(net, "ipcomp_output"); 345#endif 346 347 sav = isr->sav; 348 KASSERT(sav != NULL, ("ipcomp_output: null SA")); 349 ipcompx = sav->tdb_compalgxform; 350 KASSERT(ipcompx != NULL, ("ipcomp_output: null compression xform")); 351 352 ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */ 353 hlen = IPCOMP_HLENGTH; 354 355 ipcompstat.ipcomps_output++; 356 357 /* Check for maximum packet size violations. */ 358 switch (sav->sah->saidx.dst.sa.sa_family) { 359#ifdef INET 360 case AF_INET: 361 maxpacketsize = IP_MAXPACKET; 362 break; 363#endif /* INET */ 364#ifdef INET6 365 case AF_INET6: 366 maxpacketsize = IPV6_MAXPACKET; 367 break; 368#endif /* INET6 */ 369 default: 370 ipcompstat.ipcomps_nopf++; 371 DPRINTF(("ipcomp_output: unknown/unsupported protocol family %d" 372 ", IPCA %s/%08lx\n", 373 sav->sah->saidx.dst.sa.sa_family, 374 ipsec_address(&sav->sah->saidx.dst), 375 (u_long) ntohl(sav->spi))); 376 error = EPFNOSUPPORT; 377 goto bad; 378 } 379 if (skip + hlen + ralen > maxpacketsize) { 380 ipcompstat.ipcomps_toobig++; 381 DPRINTF(("ipcomp_output: packet in IPCA %s/%08lx got too big " 382 "(len %u, max len %u)\n", 383 ipsec_address(&sav->sah->saidx.dst), 384 (u_long) ntohl(sav->spi), 385 skip + hlen + ralen, maxpacketsize)); 386 error = EMSGSIZE; 387 goto bad; 388 } 389 390 /* Update the counters */ 391 ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip; 392 393 m = m_clone(m); 394 if (m == NULL) { 395 ipcompstat.ipcomps_hdrops++; 396 DPRINTF(("ipcomp_output: cannot clone mbuf chain, IPCA %s/%08lx\n", 397 ipsec_address(&sav->sah->saidx.dst), 398 (u_long) ntohl(sav->spi))); 399 error = ENOBUFS; 400 goto bad; 401 } 402 403 /* Inject IPCOMP header */ 404 mo = m_makespace(m, skip, hlen, &roff); 405 if (mo == NULL) { 406 ipcompstat.ipcomps_wrap++; 407 DPRINTF(("ipcomp_output: failed to inject IPCOMP header for " 408 "IPCA %s/%08lx\n", 409 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(("ipcomp_output: failed to acquire crypto descriptor\n")); 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(("ipcomp_output: failed to allocate tdb_crypto\n")); 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); 484bad: 485 if (m) 486 m_freem(m); 487 return (error); 488} 489 490/* 491 * IPComp output callback from the crypto driver. 492 */ 493static int 494ipcomp_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 tc = (struct tdb_crypto *) crp->crp_opaque; 503 KASSERT(tc != NULL, ("ipcomp_output_cb: null opaque data area!")); 504 m = (struct mbuf *) crp->crp_buf; 505 skip = tc->tc_skip; 506 rlen = crp->crp_ilen - skip; 507 508 isr = tc->tc_isr; 509 mtx_lock(&isr->lock); 510 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi); 511 if (sav == NULL) { 512 ipcompstat.ipcomps_notdb++; 513 DPRINTF(("ipcomp_output_cb: SA expired while in crypto\n")); 514 error = ENOBUFS; /*XXX*/ 515 goto bad; 516 } 517 KASSERT(isr->sav == sav, ("ipcomp_output_cb: SA changed\n")); 518 519 /* Check for crypto errors */ 520 if (crp->crp_etype) { 521 /* Reset session ID */ 522 if (sav->tdb_cryptoid != 0) 523 sav->tdb_cryptoid = crp->crp_sid; 524 525 if (crp->crp_etype == EAGAIN) { 526 KEY_FREESAV(&sav); 527 mtx_unlock(&isr->lock); 528 return crypto_dispatch(crp); 529 } 530 ipcompstat.ipcomps_noxform++; 531 DPRINTF(("ipcomp_output_cb: crypto error %d\n", crp->crp_etype)); 532 error = crp->crp_etype; 533 goto bad; 534 } 535 /* Shouldn't happen... */ 536 if (m == NULL) { 537 ipcompstat.ipcomps_crypto++; 538 DPRINTF(("ipcomp_output_cb: bogus return buffer from crypto\n")); 539 error = EINVAL; 540 goto bad; 541 } 542 ipcompstat.ipcomps_hist[sav->alg_comp]++; 543 544 if (rlen > crp->crp_olen) { 545 /* Adjust the length in the IP header */ 546 switch (sav->sah->saidx.dst.sa.sa_family) { 547#ifdef INET 548 case AF_INET: 549 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 550 break; 551#endif /* INET */ 552#ifdef INET6 553 case AF_INET6: 554 mtod(m, struct ip6_hdr *)->ip6_plen = 555 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr); 556 break; 557#endif /* INET6 */ 558 default: 559 ipcompstat.ipcomps_nopf++; 560 DPRINTF(("ipcomp_output: unknown/unsupported protocol " 561 "family %d, IPCA %s/%08lx\n", 562 sav->sah->saidx.dst.sa.sa_family, 563 ipsec_address(&sav->sah->saidx.dst), 564 (u_long) ntohl(sav->spi))); 565 error = EPFNOSUPPORT; 566 goto bad; 567 } 568 } else { 569 /* compression was useless, we have lost time */ 570 /* XXX add statistic */ 571 } 572 573 /* Release the crypto descriptor */ 574 free(tc, M_XDATA); 575 crypto_freereq(crp); 576 577 /* NB: m is reclaimed by ipsec_process_done. */ 578 error = ipsec_process_done(m, isr); 579 KEY_FREESAV(&sav); 580 mtx_unlock(&isr->lock); 581 582 return error; 583bad: 584 if (sav) 585 KEY_FREESAV(&sav); 586 mtx_unlock(&isr->lock); 587 if (m) 588 m_freem(m); 589 free(tc, M_XDATA); 590 crypto_freereq(crp); 591 return error; 592} 593 594static struct xformsw ipcomp_xformsw = { 595 XF_IPCOMP, XFT_COMP, "IPcomp", 596 ipcomp_init, ipcomp_zeroize, ipcomp_input, 597 ipcomp_output 598}; 599 600static void 601ipcomp_attach(void) 602{ 603 xform_register(&ipcomp_xformsw); 604} 605SYSINIT(ipcomp_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, ipcomp_attach, NULL) 606