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/socket.h> 39 #include <sys/kernel.h> 40 #include <sys/protosw.h> 41 #include <sys/sysctl.h> 42 43 #include <netinet/in.h> 44 #include <netinet/in_systm.h> 45 #include <netinet/ip.h> 46 #include <netinet/ip_var.h> 47 48 #include <net/route.h> 49 #include <netipsec/ipsec.h> 50 #include <netipsec/xform.h> 51 52 #ifdef INET6 53 #include <netinet/ip6.h> 54 #include <netipsec/ipsec6.h> 55 #endif 56 57 #include <netipsec/ipcomp.h> 58 #include <netipsec/ipcomp_var.h> 59 60 #include <netipsec/key.h> 61 #include <netipsec/key_debug.h> 62 63 #include <opencrypto/cryptodev.h> 64 #include <opencrypto/deflate.h> 65 #include <opencrypto/xform.h> 66 67 int ipcomp_enable = 0; 68 struct ipcompstat ipcompstat; 69 70 SYSCTL_DECL(_net_inet_ipcomp); 71 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO, 72 ipcomp_enable, CTLFLAG_RW, &ipcomp_enable, 0, ""); 73 SYSCTL_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS, 74 stats, CTLFLAG_RD, &ipcompstat, ipcompstat, ""); 75 76 static int ipcomp_input_cb(struct cryptop *crp); 77 static int ipcomp_output_cb(struct cryptop *crp); 78 79 struct comp_algo * 80 ipcomp_algorithm_lookup(int alg) 81 { 82 if (alg >= IPCOMP_ALG_MAX) 83 return NULL; 84 switch (alg) { 85 case SADB_X_CALG_DEFLATE: 86 return &comp_algo_deflate; 87 } 88 return NULL; 89 } 90 91 /* 92 * ipcomp_init() is called when an CPI is being set up. 93 */ 94 static int 95 ipcomp_init(struct secasvar *sav, struct xformsw *xsp) 96 { 97 struct comp_algo *tcomp; 98 struct cryptoini cric; 99 100 /* NB: algorithm really comes in alg_enc and not alg_comp! */ 101 tcomp = ipcomp_algorithm_lookup(sav->alg_enc); 102 if (tcomp == NULL) { 103 DPRINTF(("ipcomp_init: unsupported compression algorithm %d\n", 104 sav->alg_comp)); 105 return EINVAL; 106 } 107 sav->alg_comp = sav->alg_enc; /* set for doing histogram */ 108 sav->tdb_xform = xsp; 109 sav->tdb_compalgxform = tcomp; 110 111 /* Initialize crypto session */ 112 bzero(&cric, sizeof (cric)); 113 cric.cri_alg = sav->tdb_compalgxform->type; 114 115 return crypto_newsession(&sav->tdb_cryptoid, &cric, crypto_support); 116 } 117 118 /* 119 * ipcomp_zeroize() used when IPCA is deleted 120 */ 121 static int 122 ipcomp_zeroize(struct secasvar *sav) 123 { 124 int err; 125 126 err = crypto_freesession(sav->tdb_cryptoid); 127 sav->tdb_cryptoid = 0; 128 return err; 129 } 130 131 /* 132 * ipcomp_input() gets called to uncompress an input packet 133 */ 134 static int 135 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) 136 { 137 struct tdb_crypto *tc; 138 struct cryptodesc *crdc; 139 struct cryptop *crp; 140 int hlen = IPCOMP_HLENGTH; 141 142 #if 0 143 SPLASSERT(net, "ipcomp_input"); 144 #endif 145 146 /* Get crypto descriptors */ 147 crp = crypto_getreq(1); 148 if (crp == NULL) { 149 m_freem(m); 150 DPRINTF(("ipcomp_input: no crypto descriptors\n")); 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(("ipcomp_input: cannot allocate tdb_crypto\n")); 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; 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 s, 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 KASSERT(tc != NULL, ("ipcomp_input_cb: 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 s = splnet(); 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 splx(s); 256 return crypto_dispatch(crp); 257 } 258 259 ipcompstat.ipcomps_noxform++; 260 DPRINTF(("ipcomp_input_cb: crypto error %d\n", 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(("ipcomp_input_cb: null mbuf returned from crypto\n")); 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(("ipcomp_input_cb: m_pullup failed\n")); 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(("ipcomp_input_cb: bad mbuf chain, IPCA %s/%08lx\n", 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 splx(s); 310 return error; 311 bad: 312 if (sav) 313 KEY_FREESAV(&sav); 314 splx(s); 315 if (m) 316 m_freem(m); 317 if (tc != NULL) 318 free(tc, M_XDATA); 319 if (crp) 320 crypto_freereq(crp); 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 #if 0 347 SPLASSERT(net, "ipcomp_output"); 348 #endif 349 350 sav = isr->sav; 351 KASSERT(sav != NULL, ("ipcomp_output: null SA")); 352 ipcompx = sav->tdb_compalgxform; 353 KASSERT(ipcompx != NULL, ("ipcomp_output: null compression xform")); 354 355 ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */ 356 hlen = IPCOMP_HLENGTH; 357 358 ipcompstat.ipcomps_output++; 359 360 /* Check for maximum packet size violations. */ 361 switch (sav->sah->saidx.dst.sa.sa_family) { 362 #ifdef INET 363 case AF_INET: 364 maxpacketsize = IP_MAXPACKET; 365 break; 366 #endif /* INET */ 367 #ifdef INET6 368 case AF_INET6: 369 maxpacketsize = IPV6_MAXPACKET; 370 break; 371 #endif /* INET6 */ 372 default: 373 ipcompstat.ipcomps_nopf++; 374 DPRINTF(("ipcomp_output: unknown/unsupported protocol family %d" 375 ", IPCA %s/%08lx\n", 376 sav->sah->saidx.dst.sa.sa_family, 377 ipsec_address(&sav->sah->saidx.dst), 378 (u_long) ntohl(sav->spi))); 379 error = EPFNOSUPPORT; 380 goto bad; 381 } 382 if (skip + hlen + ralen > maxpacketsize) { 383 ipcompstat.ipcomps_toobig++; 384 DPRINTF(("ipcomp_output: packet in IPCA %s/%08lx got too big " 385 "(len %u, max len %u)\n", 386 ipsec_address(&sav->sah->saidx.dst), 387 (u_long) ntohl(sav->spi), 388 skip + hlen + ralen, maxpacketsize)); 389 error = EMSGSIZE; 390 goto bad; 391 } 392 393 /* Update the counters */ 394 ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip; 395 396 m = m_clone(m); 397 if (m == NULL) { 398 ipcompstat.ipcomps_hdrops++; 399 DPRINTF(("ipcomp_output: cannot clone mbuf chain, IPCA %s/%08lx\n", 400 ipsec_address(&sav->sah->saidx.dst), 401 (u_long) ntohl(sav->spi))); 402 error = ENOBUFS; 403 goto bad; 404 } 405 406 /* Inject IPCOMP header */ 407 mo = m_makespace(m, skip, hlen, &roff); 408 if (mo == NULL) { 409 ipcompstat.ipcomps_wrap++; 410 DPRINTF(("ipcomp_output: failed to inject IPCOMP header for " 411 "IPCA %s/%08lx\n", 412 ipsec_address(&sav->sah->saidx.dst), 413 (u_long) ntohl(sav->spi))); 414 error = ENOBUFS; 415 goto bad; 416 } 417 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff); 418 419 /* Initialize the IPCOMP header */ 420 /* XXX alignment always correct? */ 421 switch (sav->sah->saidx.dst.sa.sa_family) { 422 #ifdef INET 423 case AF_INET: 424 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p; 425 break; 426 #endif /* INET */ 427 #ifdef INET6 428 case AF_INET6: 429 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt; 430 break; 431 #endif 432 } 433 ipcomp->comp_flags = 0; 434 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi)); 435 436 /* Fix Next Protocol in IPv4/IPv6 header */ 437 prot = IPPROTO_IPCOMP; 438 m_copyback(m, protoff, sizeof(u_int8_t), (u_char *) &prot); 439 440 /* Ok now, we can pass to the crypto processing */ 441 442 /* Get crypto descriptors */ 443 crp = crypto_getreq(1); 444 if (crp == NULL) { 445 ipcompstat.ipcomps_crypto++; 446 DPRINTF(("ipcomp_output: failed to acquire crypto descriptor\n")); 447 error = ENOBUFS; 448 goto bad; 449 } 450 crdc = crp->crp_desc; 451 452 /* Compression descriptor */ 453 crdc->crd_skip = skip + hlen; 454 crdc->crd_len = m->m_pkthdr.len - (skip + hlen); 455 crdc->crd_flags = CRD_F_COMP; 456 crdc->crd_inject = skip + hlen; 457 458 /* Compression operation */ 459 crdc->crd_alg = ipcompx->type; 460 461 /* IPsec-specific opaque crypto info */ 462 tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto), 463 M_XDATA, M_NOWAIT|M_ZERO); 464 if (tc == NULL) { 465 ipcompstat.ipcomps_crypto++; 466 DPRINTF(("ipcomp_output: failed to allocate tdb_crypto\n")); 467 crypto_freereq(crp); 468 error = ENOBUFS; 469 goto bad; 470 } 471 472 tc->tc_isr = isr; 473 tc->tc_spi = sav->spi; 474 tc->tc_dst = sav->sah->saidx.dst; 475 tc->tc_proto = sav->sah->saidx.proto; 476 tc->tc_skip = skip + hlen; 477 478 /* Crypto operation descriptor */ 479 crp->crp_ilen = m->m_pkthdr.len; /* Total input length */ 480 crp->crp_flags = CRYPTO_F_IMBUF; 481 crp->crp_buf = (caddr_t) m; 482 crp->crp_callback = ipcomp_output_cb; 483 crp->crp_opaque = (caddr_t) tc; 484 crp->crp_sid = sav->tdb_cryptoid; 485 486 return crypto_dispatch(crp); 487 bad: 488 if (m) 489 m_freem(m); 490 return (error); 491 } 492 493 /* 494 * IPComp output callback from the crypto driver. 495 */ 496 static int 497 ipcomp_output_cb(struct cryptop *crp) 498 { 499 struct tdb_crypto *tc; 500 struct ipsecrequest *isr; 501 struct secasvar *sav; 502 struct mbuf *m; 503 int s, error, skip, rlen; 504 505 tc = (struct tdb_crypto *) crp->crp_opaque; 506 KASSERT(tc != NULL, ("ipcomp_output_cb: null opaque data area!")); 507 m = (struct mbuf *) crp->crp_buf; 508 skip = tc->tc_skip; 509 rlen = crp->crp_ilen - skip; 510 511 s = splnet(); 512 513 isr = tc->tc_isr; 514 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi); 515 if (sav == NULL) { 516 ipcompstat.ipcomps_notdb++; 517 DPRINTF(("ipcomp_output_cb: SA expired while in crypto\n")); 518 error = ENOBUFS; /*XXX*/ 519 goto bad; 520 } 521 KASSERT(isr->sav == sav, ("ipcomp_output_cb: SA changed\n")); 522 523 /* Check for crypto errors */ 524 if (crp->crp_etype) { 525 /* Reset session ID */ 526 if (sav->tdb_cryptoid != 0) 527 sav->tdb_cryptoid = crp->crp_sid; 528 529 if (crp->crp_etype == EAGAIN) { 530 KEY_FREESAV(&sav); 531 splx(s); 532 return crypto_dispatch(crp); 533 } 534 ipcompstat.ipcomps_noxform++; 535 DPRINTF(("ipcomp_output_cb: crypto error %d\n", 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(("ipcomp_output_cb: bogus return buffer from crypto\n")); 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(("ipcomp_output: unknown/unsupported protocol " 565 "family %d, IPCA %s/%08lx\n", 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 splx(s); 585 return error; 586 bad: 587 if (sav) 588 KEY_FREESAV(&sav); 589 splx(s); 590 if (m) 591 m_freem(m); 592 free(tc, M_XDATA); 593 crypto_freereq(crp); 594 return error; 595 } 596 597 static struct xformsw ipcomp_xformsw = { 598 XF_IPCOMP, XFT_COMP, "IPcomp", 599 ipcomp_init, ipcomp_zeroize, ipcomp_input, 600 ipcomp_output 601 }; 602 603 static void 604 ipcomp_attach(void) 605 { 606 xform_register(&ipcomp_xformsw); 607 } 608 SYSINIT(ipcomp_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, ipcomp_attach, NULL) 609