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 <net/vnet.h> 52 53 #include <netipsec/ipsec.h> 54 #include <netipsec/xform.h> 55 56 #ifdef INET6 57 #include <netinet/ip6.h> 58 #include <netipsec/ipsec6.h> 59 #endif 60 61 #include <netipsec/ipcomp.h> 62 #include <netipsec/ipcomp_var.h> 63 64 #include <netipsec/key.h> 65 #include <netipsec/key_debug.h> 66 67 #include <opencrypto/cryptodev.h> 68 #include <opencrypto/deflate.h> 69 #include <opencrypto/xform.h> 70 71 VNET_DEFINE(int, ipcomp_enable) = 0; 72 VNET_DEFINE(struct ipcompstat, ipcompstat); 73 74 SYSCTL_DECL(_net_inet_ipcomp); 75 SYSCTL_VNET_INT(_net_inet_ipcomp, OID_AUTO, 76 ipcomp_enable, CTLFLAG_RW, &VNET_NAME(ipcomp_enable), 0, ""); 77 SYSCTL_VNET_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS, 78 stats, CTLFLAG_RD, &VNET_NAME(ipcompstat), ipcompstat, ""); 79 80 static int ipcomp_input_cb(struct cryptop *crp); 81 static int ipcomp_output_cb(struct cryptop *crp); 82 83 struct comp_algo * 84 ipcomp_algorithm_lookup(int alg) 85 { 86 if (alg >= IPCOMP_ALG_MAX) 87 return NULL; 88 switch (alg) { 89 case SADB_X_CALG_DEFLATE: 90 return &comp_algo_deflate; 91 } 92 return NULL; 93 } 94 95 /* 96 * ipcomp_init() is called when an CPI is being set up. 97 */ 98 static int 99 ipcomp_init(struct secasvar *sav, struct xformsw *xsp) 100 { 101 struct comp_algo *tcomp; 102 struct cryptoini cric; 103 104 /* NB: algorithm really comes in alg_enc and not alg_comp! */ 105 tcomp = ipcomp_algorithm_lookup(sav->alg_enc); 106 if (tcomp == NULL) { 107 DPRINTF(("%s: unsupported compression algorithm %d\n", __func__, 108 sav->alg_comp)); 109 return EINVAL; 110 } 111 sav->alg_comp = sav->alg_enc; /* set for doing histogram */ 112 sav->tdb_xform = xsp; 113 sav->tdb_compalgxform = tcomp; 114 115 /* Initialize crypto session */ 116 bzero(&cric, sizeof (cric)); 117 cric.cri_alg = sav->tdb_compalgxform->type; 118 119 return crypto_newsession(&sav->tdb_cryptoid, &cric, V_crypto_support); 120 } 121 122 /* 123 * ipcomp_zeroize() used when IPCA is deleted 124 */ 125 static int 126 ipcomp_zeroize(struct secasvar *sav) 127 { 128 int err; 129 130 err = crypto_freesession(sav->tdb_cryptoid); 131 sav->tdb_cryptoid = 0; 132 return err; 133 } 134 135 /* 136 * ipcomp_input() gets called to uncompress an input packet 137 */ 138 static int 139 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) 140 { 141 struct tdb_crypto *tc; 142 struct cryptodesc *crdc; 143 struct cryptop *crp; 144 int hlen = IPCOMP_HLENGTH; 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 V_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 V_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 crd = crp->crp_desc; 223 224 tc = (struct tdb_crypto *) crp->crp_opaque; 225 IPSEC_ASSERT(tc != NULL, ("null opaque crypto data area!")); 226 skip = tc->tc_skip; 227 protoff = tc->tc_protoff; 228 mtag = (struct mtag *) tc->tc_ptr; 229 m = (struct mbuf *) crp->crp_buf; 230 231 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi); 232 if (sav == NULL) { 233 V_ipcompstat.ipcomps_notdb++; 234 DPRINTF(("%s: SA expired while in crypto\n", __func__)); 235 error = ENOBUFS; /*XXX*/ 236 goto bad; 237 } 238 239 saidx = &sav->sah->saidx; 240 IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET || 241 saidx->dst.sa.sa_family == AF_INET6, 242 ("unexpected protocol family %u", saidx->dst.sa.sa_family)); 243 244 /* Check for crypto errors */ 245 if (crp->crp_etype) { 246 /* Reset the session ID */ 247 if (sav->tdb_cryptoid != 0) 248 sav->tdb_cryptoid = crp->crp_sid; 249 250 if (crp->crp_etype == EAGAIN) { 251 KEY_FREESAV(&sav); 252 error = crypto_dispatch(crp); 253 return error; 254 } 255 256 V_ipcompstat.ipcomps_noxform++; 257 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype)); 258 error = crp->crp_etype; 259 goto bad; 260 } 261 /* Shouldn't happen... */ 262 if (m == NULL) { 263 V_ipcompstat.ipcomps_crypto++; 264 DPRINTF(("%s: null mbuf returned from crypto\n", __func__)); 265 error = EINVAL; 266 goto bad; 267 } 268 V_ipcompstat.ipcomps_hist[sav->alg_comp]++; 269 270 clen = crp->crp_olen; /* Length of data after processing */ 271 272 /* Release the crypto descriptors */ 273 free(tc, M_XDATA), tc = NULL; 274 crypto_freereq(crp), crp = NULL; 275 276 /* In case it's not done already, adjust the size of the mbuf chain */ 277 m->m_pkthdr.len = clen + hlen + skip; 278 279 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) { 280 V_ipcompstat.ipcomps_hdrops++; /*XXX*/ 281 DPRINTF(("%s: m_pullup failed\n", __func__)); 282 error = EINVAL; /*XXX*/ 283 goto bad; 284 } 285 286 /* Keep the next protocol field */ 287 addr = (caddr_t) mtod(m, struct ip *) + skip; 288 nproto = ((struct ipcomp *) addr)->comp_nxt; 289 290 /* Remove the IPCOMP header */ 291 error = m_striphdr(m, skip, hlen); 292 if (error) { 293 V_ipcompstat.ipcomps_hdrops++; 294 DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__, 295 ipsec_address(&sav->sah->saidx.dst), 296 (u_long) ntohl(sav->spi))); 297 goto bad; 298 } 299 300 /* Restore the Next Protocol field */ 301 m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto); 302 303 IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, NULL); 304 305 KEY_FREESAV(&sav); 306 return error; 307 bad: 308 if (sav) 309 KEY_FREESAV(&sav); 310 if (m) 311 m_freem(m); 312 if (tc != NULL) 313 free(tc, M_XDATA); 314 if (crp) 315 crypto_freereq(crp); 316 return error; 317 } 318 319 /* 320 * IPComp output routine, called by ipsec[46]_process_packet() 321 */ 322 static int 323 ipcomp_output( 324 struct mbuf *m, 325 struct ipsecrequest *isr, 326 struct mbuf **mp, 327 int skip, 328 int protoff 329 ) 330 { 331 struct secasvar *sav; 332 struct comp_algo *ipcompx; 333 int error, ralen, hlen, maxpacketsize, roff; 334 u_int8_t prot; 335 struct cryptodesc *crdc; 336 struct cryptop *crp; 337 struct tdb_crypto *tc; 338 struct mbuf *mo; 339 struct ipcomp *ipcomp; 340 341 sav = isr->sav; 342 IPSEC_ASSERT(sav != NULL, ("null SA")); 343 ipcompx = sav->tdb_compalgxform; 344 IPSEC_ASSERT(ipcompx != NULL, ("null compression xform")); 345 346 ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */ 347 hlen = IPCOMP_HLENGTH; 348 349 V_ipcompstat.ipcomps_output++; 350 351 /* Check for maximum packet size violations. */ 352 switch (sav->sah->saidx.dst.sa.sa_family) { 353 #ifdef INET 354 case AF_INET: 355 maxpacketsize = IP_MAXPACKET; 356 break; 357 #endif /* INET */ 358 #ifdef INET6 359 case AF_INET6: 360 maxpacketsize = IPV6_MAXPACKET; 361 break; 362 #endif /* INET6 */ 363 default: 364 V_ipcompstat.ipcomps_nopf++; 365 DPRINTF(("%s: unknown/unsupported protocol family %d, " 366 "IPCA %s/%08lx\n", __func__, 367 sav->sah->saidx.dst.sa.sa_family, 368 ipsec_address(&sav->sah->saidx.dst), 369 (u_long) ntohl(sav->spi))); 370 error = EPFNOSUPPORT; 371 goto bad; 372 } 373 if (skip + hlen + ralen > maxpacketsize) { 374 V_ipcompstat.ipcomps_toobig++; 375 DPRINTF(("%s: packet in IPCA %s/%08lx got too big " 376 "(len %u, max len %u)\n", __func__, 377 ipsec_address(&sav->sah->saidx.dst), 378 (u_long) ntohl(sav->spi), 379 skip + hlen + ralen, maxpacketsize)); 380 error = EMSGSIZE; 381 goto bad; 382 } 383 384 /* Update the counters */ 385 V_ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip; 386 387 m = m_unshare(m, M_NOWAIT); 388 if (m == NULL) { 389 V_ipcompstat.ipcomps_hdrops++; 390 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n", 391 __func__, ipsec_address(&sav->sah->saidx.dst), 392 (u_long) ntohl(sav->spi))); 393 error = ENOBUFS; 394 goto bad; 395 } 396 397 /* Inject IPCOMP header */ 398 mo = m_makespace(m, skip, hlen, &roff); 399 if (mo == NULL) { 400 V_ipcompstat.ipcomps_wrap++; 401 DPRINTF(("%s: IPCOMP header inject failed for IPCA %s/%08lx\n", 402 __func__, ipsec_address(&sav->sah->saidx.dst), 403 (u_long) ntohl(sav->spi))); 404 error = ENOBUFS; 405 goto bad; 406 } 407 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff); 408 409 /* Initialize the IPCOMP header */ 410 /* XXX alignment always correct? */ 411 switch (sav->sah->saidx.dst.sa.sa_family) { 412 #ifdef INET 413 case AF_INET: 414 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p; 415 break; 416 #endif /* INET */ 417 #ifdef INET6 418 case AF_INET6: 419 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt; 420 break; 421 #endif 422 } 423 ipcomp->comp_flags = 0; 424 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi)); 425 426 /* Fix Next Protocol in IPv4/IPv6 header */ 427 prot = IPPROTO_IPCOMP; 428 m_copyback(m, protoff, sizeof(u_int8_t), (u_char *) &prot); 429 430 /* Ok now, we can pass to the crypto processing */ 431 432 /* Get crypto descriptors */ 433 crp = crypto_getreq(1); 434 if (crp == NULL) { 435 V_ipcompstat.ipcomps_crypto++; 436 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__)); 437 error = ENOBUFS; 438 goto bad; 439 } 440 crdc = crp->crp_desc; 441 442 /* Compression descriptor */ 443 crdc->crd_skip = skip + hlen; 444 crdc->crd_len = m->m_pkthdr.len - (skip + hlen); 445 crdc->crd_flags = CRD_F_COMP; 446 crdc->crd_inject = skip + hlen; 447 448 /* Compression operation */ 449 crdc->crd_alg = ipcompx->type; 450 451 /* IPsec-specific opaque crypto info */ 452 tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto), 453 M_XDATA, M_NOWAIT|M_ZERO); 454 if (tc == NULL) { 455 V_ipcompstat.ipcomps_crypto++; 456 DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__)); 457 crypto_freereq(crp); 458 error = ENOBUFS; 459 goto bad; 460 } 461 462 tc->tc_isr = isr; 463 tc->tc_spi = sav->spi; 464 tc->tc_dst = sav->sah->saidx.dst; 465 tc->tc_proto = sav->sah->saidx.proto; 466 tc->tc_skip = skip + hlen; 467 468 /* Crypto operation descriptor */ 469 crp->crp_ilen = m->m_pkthdr.len; /* Total input length */ 470 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC; 471 crp->crp_buf = (caddr_t) m; 472 crp->crp_callback = ipcomp_output_cb; 473 crp->crp_opaque = (caddr_t) tc; 474 crp->crp_sid = sav->tdb_cryptoid; 475 476 return crypto_dispatch(crp); 477 bad: 478 if (m) 479 m_freem(m); 480 return (error); 481 } 482 483 /* 484 * IPComp output callback from the crypto driver. 485 */ 486 static int 487 ipcomp_output_cb(struct cryptop *crp) 488 { 489 struct tdb_crypto *tc; 490 struct ipsecrequest *isr; 491 struct secasvar *sav; 492 struct mbuf *m; 493 int error, skip, rlen; 494 495 tc = (struct tdb_crypto *) crp->crp_opaque; 496 IPSEC_ASSERT(tc != NULL, ("null opaque data area!")); 497 m = (struct mbuf *) crp->crp_buf; 498 skip = tc->tc_skip; 499 rlen = crp->crp_ilen - skip; 500 501 isr = tc->tc_isr; 502 IPSECREQUEST_LOCK(isr); 503 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi); 504 if (sav == NULL) { 505 V_ipcompstat.ipcomps_notdb++; 506 DPRINTF(("%s: SA expired while in crypto\n", __func__)); 507 error = ENOBUFS; /*XXX*/ 508 goto bad; 509 } 510 IPSEC_ASSERT(isr->sav == sav, ("SA changed\n")); 511 512 /* Check for crypto errors */ 513 if (crp->crp_etype) { 514 /* Reset session ID */ 515 if (sav->tdb_cryptoid != 0) 516 sav->tdb_cryptoid = crp->crp_sid; 517 518 if (crp->crp_etype == EAGAIN) { 519 KEY_FREESAV(&sav); 520 IPSECREQUEST_UNLOCK(isr); 521 error = crypto_dispatch(crp); 522 return error; 523 } 524 V_ipcompstat.ipcomps_noxform++; 525 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype)); 526 error = crp->crp_etype; 527 goto bad; 528 } 529 /* Shouldn't happen... */ 530 if (m == NULL) { 531 V_ipcompstat.ipcomps_crypto++; 532 DPRINTF(("%s: bogus return buffer from crypto\n", __func__)); 533 error = EINVAL; 534 goto bad; 535 } 536 V_ipcompstat.ipcomps_hist[sav->alg_comp]++; 537 538 if (rlen > crp->crp_olen) { 539 /* Adjust the length in the IP header */ 540 switch (sav->sah->saidx.dst.sa.sa_family) { 541 #ifdef INET 542 case AF_INET: 543 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 544 break; 545 #endif /* INET */ 546 #ifdef INET6 547 case AF_INET6: 548 mtod(m, struct ip6_hdr *)->ip6_plen = 549 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr); 550 break; 551 #endif /* INET6 */ 552 default: 553 V_ipcompstat.ipcomps_nopf++; 554 DPRINTF(("%s: unknown/unsupported protocol " 555 "family %d, IPCA %s/%08lx\n", __func__, 556 sav->sah->saidx.dst.sa.sa_family, 557 ipsec_address(&sav->sah->saidx.dst), 558 (u_long) ntohl(sav->spi))); 559 error = EPFNOSUPPORT; 560 goto bad; 561 } 562 } else { 563 /* compression was useless, we have lost time */ 564 /* XXX add statistic */ 565 } 566 567 /* Release the crypto descriptor */ 568 free(tc, M_XDATA); 569 crypto_freereq(crp); 570 571 /* NB: m is reclaimed by ipsec_process_done. */ 572 error = ipsec_process_done(m, isr); 573 KEY_FREESAV(&sav); 574 IPSECREQUEST_UNLOCK(isr); 575 return error; 576 bad: 577 if (sav) 578 KEY_FREESAV(&sav); 579 IPSECREQUEST_UNLOCK(isr); 580 if (m) 581 m_freem(m); 582 free(tc, M_XDATA); 583 crypto_freereq(crp); 584 return error; 585 } 586 587 static struct xformsw ipcomp_xformsw = { 588 XF_IPCOMP, XFT_COMP, "IPcomp", 589 ipcomp_init, ipcomp_zeroize, ipcomp_input, 590 ipcomp_output 591 }; 592 593 static void 594 ipcomp_attach(void) 595 { 596 597 xform_register(&ipcomp_xformsw); 598 } 599 600 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipcomp_attach, NULL); 601