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 #include <sys/vimage.h> 45 46 #include <netinet/in.h> 47 #include <netinet/in_systm.h> 48 #include <netinet/ip.h> 49 #include <netinet/ip_var.h> 50 51 #include <net/route.h> 52 #include <netipsec/ipsec.h> 53 #include <netipsec/xform.h> 54 55 #ifdef INET6 56 #include <netinet/ip6.h> 57 #include <netipsec/ipsec6.h> 58 #endif 59 60 #include <netipsec/ipcomp.h> 61 #include <netipsec/ipcomp_var.h> 62 63 #include <netipsec/key.h> 64 #include <netipsec/key_debug.h> 65 66 #include <opencrypto/cryptodev.h> 67 #include <opencrypto/deflate.h> 68 #include <opencrypto/xform.h> 69 70 #ifdef VIMAGE_GLOBALS 71 int ipcomp_enable; 72 struct ipcompstat ipcompstat; 73 #endif 74 75 SYSCTL_DECL(_net_inet_ipcomp); 76 SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ipcomp, OID_AUTO, 77 ipcomp_enable, CTLFLAG_RW, ipcomp_enable, 0, ""); 78 SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet_ipcomp, IPSECCTL_STATS, 79 stats, CTLFLAG_RD, ipcompstat, ipcompstat, ""); 80 81 static int ipcomp_input_cb(struct cryptop *crp); 82 static int ipcomp_output_cb(struct cryptop *crp); 83 static int ipcomp_iattach(const void *); 84 85 #ifndef VIMAGE_GLOBALS 86 static const vnet_modinfo_t vnet_ipcomp_modinfo = { 87 .vmi_id = VNET_MOD_IPCOMP, 88 .vmi_name = "ipsec_ipcomp", 89 .vmi_dependson = VNET_MOD_IPSEC, 90 .vmi_iattach = ipcomp_iattach 91 }; 92 #endif /* !VIMAGE_GLOBALS */ 93 94 struct comp_algo * 95 ipcomp_algorithm_lookup(int alg) 96 { 97 if (alg >= IPCOMP_ALG_MAX) 98 return NULL; 99 switch (alg) { 100 case SADB_X_CALG_DEFLATE: 101 return &comp_algo_deflate; 102 } 103 return NULL; 104 } 105 106 /* 107 * ipcomp_init() is called when an CPI is being set up. 108 */ 109 static int 110 ipcomp_init(struct secasvar *sav, struct xformsw *xsp) 111 { 112 INIT_VNET_IPSEC(curvnet); 113 struct comp_algo *tcomp; 114 struct cryptoini cric; 115 116 /* NB: algorithm really comes in alg_enc and not alg_comp! */ 117 tcomp = ipcomp_algorithm_lookup(sav->alg_enc); 118 if (tcomp == NULL) { 119 DPRINTF(("%s: unsupported compression algorithm %d\n", __func__, 120 sav->alg_comp)); 121 return EINVAL; 122 } 123 sav->alg_comp = sav->alg_enc; /* set for doing histogram */ 124 sav->tdb_xform = xsp; 125 sav->tdb_compalgxform = tcomp; 126 127 /* Initialize crypto session */ 128 bzero(&cric, sizeof (cric)); 129 cric.cri_alg = sav->tdb_compalgxform->type; 130 131 return crypto_newsession(&sav->tdb_cryptoid, &cric, V_crypto_support); 132 } 133 134 /* 135 * ipcomp_zeroize() used when IPCA is deleted 136 */ 137 static int 138 ipcomp_zeroize(struct secasvar *sav) 139 { 140 int err; 141 142 err = crypto_freesession(sav->tdb_cryptoid); 143 sav->tdb_cryptoid = 0; 144 return err; 145 } 146 147 /* 148 * ipcomp_input() gets called to uncompress an input packet 149 */ 150 static int 151 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) 152 { 153 INIT_VNET_IPSEC(curvnet); 154 struct tdb_crypto *tc; 155 struct cryptodesc *crdc; 156 struct cryptop *crp; 157 int hlen = IPCOMP_HLENGTH; 158 159 /* Get crypto descriptors */ 160 crp = crypto_getreq(1); 161 if (crp == NULL) { 162 m_freem(m); 163 DPRINTF(("%s: no crypto descriptors\n", __func__)); 164 V_ipcompstat.ipcomps_crypto++; 165 return ENOBUFS; 166 } 167 /* Get IPsec-specific opaque pointer */ 168 tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO); 169 if (tc == NULL) { 170 m_freem(m); 171 crypto_freereq(crp); 172 DPRINTF(("%s: cannot allocate tdb_crypto\n", __func__)); 173 V_ipcompstat.ipcomps_crypto++; 174 return ENOBUFS; 175 } 176 crdc = crp->crp_desc; 177 178 crdc->crd_skip = skip + hlen; 179 crdc->crd_len = m->m_pkthdr.len - (skip + hlen); 180 crdc->crd_inject = skip; 181 182 tc->tc_ptr = 0; 183 184 /* Decompression operation */ 185 crdc->crd_alg = sav->tdb_compalgxform->type; 186 187 /* Crypto operation descriptor */ 188 crp->crp_ilen = m->m_pkthdr.len - (skip + hlen); 189 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC; 190 crp->crp_buf = (caddr_t) m; 191 crp->crp_callback = ipcomp_input_cb; 192 crp->crp_sid = sav->tdb_cryptoid; 193 crp->crp_opaque = (caddr_t) tc; 194 195 /* These are passed as-is to the callback */ 196 tc->tc_spi = sav->spi; 197 tc->tc_dst = sav->sah->saidx.dst; 198 tc->tc_proto = sav->sah->saidx.proto; 199 tc->tc_protoff = protoff; 200 tc->tc_skip = skip; 201 202 return crypto_dispatch(crp); 203 } 204 205 #ifdef INET6 206 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do { \ 207 if (saidx->dst.sa.sa_family == AF_INET6) { \ 208 error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \ 209 } else { \ 210 error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \ 211 } \ 212 } while (0) 213 #else 214 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) \ 215 (error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag)) 216 #endif 217 218 /* 219 * IPComp input callback from the crypto driver. 220 */ 221 static int 222 ipcomp_input_cb(struct cryptop *crp) 223 { 224 INIT_VNET_IPSEC(curvnet); 225 struct cryptodesc *crd; 226 struct tdb_crypto *tc; 227 int skip, protoff; 228 struct mtag *mtag; 229 struct mbuf *m; 230 struct secasvar *sav; 231 struct secasindex *saidx; 232 int hlen = IPCOMP_HLENGTH, error, clen; 233 u_int8_t nproto; 234 caddr_t addr; 235 236 crd = crp->crp_desc; 237 238 tc = (struct tdb_crypto *) crp->crp_opaque; 239 IPSEC_ASSERT(tc != NULL, ("null opaque crypto data area!")); 240 skip = tc->tc_skip; 241 protoff = tc->tc_protoff; 242 mtag = (struct mtag *) tc->tc_ptr; 243 m = (struct mbuf *) crp->crp_buf; 244 245 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi); 246 if (sav == NULL) { 247 V_ipcompstat.ipcomps_notdb++; 248 DPRINTF(("%s: SA expired while in crypto\n", __func__)); 249 error = ENOBUFS; /*XXX*/ 250 goto bad; 251 } 252 253 saidx = &sav->sah->saidx; 254 IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET || 255 saidx->dst.sa.sa_family == AF_INET6, 256 ("unexpected protocol family %u", saidx->dst.sa.sa_family)); 257 258 /* Check for crypto errors */ 259 if (crp->crp_etype) { 260 /* Reset the session ID */ 261 if (sav->tdb_cryptoid != 0) 262 sav->tdb_cryptoid = crp->crp_sid; 263 264 if (crp->crp_etype == EAGAIN) { 265 KEY_FREESAV(&sav); 266 error = crypto_dispatch(crp); 267 return error; 268 } 269 270 V_ipcompstat.ipcomps_noxform++; 271 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype)); 272 error = crp->crp_etype; 273 goto bad; 274 } 275 /* Shouldn't happen... */ 276 if (m == NULL) { 277 V_ipcompstat.ipcomps_crypto++; 278 DPRINTF(("%s: null mbuf returned from crypto\n", __func__)); 279 error = EINVAL; 280 goto bad; 281 } 282 V_ipcompstat.ipcomps_hist[sav->alg_comp]++; 283 284 clen = crp->crp_olen; /* Length of data after processing */ 285 286 /* Release the crypto descriptors */ 287 free(tc, M_XDATA), tc = NULL; 288 crypto_freereq(crp), crp = NULL; 289 290 /* In case it's not done already, adjust the size of the mbuf chain */ 291 m->m_pkthdr.len = clen + hlen + skip; 292 293 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) { 294 V_ipcompstat.ipcomps_hdrops++; /*XXX*/ 295 DPRINTF(("%s: m_pullup failed\n", __func__)); 296 error = EINVAL; /*XXX*/ 297 goto bad; 298 } 299 300 /* Keep the next protocol field */ 301 addr = (caddr_t) mtod(m, struct ip *) + skip; 302 nproto = ((struct ipcomp *) addr)->comp_nxt; 303 304 /* Remove the IPCOMP header */ 305 error = m_striphdr(m, skip, hlen); 306 if (error) { 307 V_ipcompstat.ipcomps_hdrops++; 308 DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__, 309 ipsec_address(&sav->sah->saidx.dst), 310 (u_long) ntohl(sav->spi))); 311 goto bad; 312 } 313 314 /* Restore the Next Protocol field */ 315 m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto); 316 317 IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, NULL); 318 319 KEY_FREESAV(&sav); 320 return error; 321 bad: 322 if (sav) 323 KEY_FREESAV(&sav); 324 if (m) 325 m_freem(m); 326 if (tc != NULL) 327 free(tc, M_XDATA); 328 if (crp) 329 crypto_freereq(crp); 330 return error; 331 } 332 333 /* 334 * IPComp output routine, called by ipsec[46]_process_packet() 335 */ 336 static int 337 ipcomp_output( 338 struct mbuf *m, 339 struct ipsecrequest *isr, 340 struct mbuf **mp, 341 int skip, 342 int protoff 343 ) 344 { 345 INIT_VNET_IPSEC(curvnet); 346 struct secasvar *sav; 347 struct comp_algo *ipcompx; 348 int error, ralen, hlen, maxpacketsize, roff; 349 u_int8_t prot; 350 struct cryptodesc *crdc; 351 struct cryptop *crp; 352 struct tdb_crypto *tc; 353 struct mbuf *mo; 354 struct ipcomp *ipcomp; 355 356 sav = isr->sav; 357 IPSEC_ASSERT(sav != NULL, ("null SA")); 358 ipcompx = sav->tdb_compalgxform; 359 IPSEC_ASSERT(ipcompx != NULL, ("null compression xform")); 360 361 ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */ 362 hlen = IPCOMP_HLENGTH; 363 364 V_ipcompstat.ipcomps_output++; 365 366 /* Check for maximum packet size violations. */ 367 switch (sav->sah->saidx.dst.sa.sa_family) { 368 #ifdef INET 369 case AF_INET: 370 maxpacketsize = IP_MAXPACKET; 371 break; 372 #endif /* INET */ 373 #ifdef INET6 374 case AF_INET6: 375 maxpacketsize = IPV6_MAXPACKET; 376 break; 377 #endif /* INET6 */ 378 default: 379 V_ipcompstat.ipcomps_nopf++; 380 DPRINTF(("%s: unknown/unsupported protocol family %d, " 381 "IPCA %s/%08lx\n", __func__, 382 sav->sah->saidx.dst.sa.sa_family, 383 ipsec_address(&sav->sah->saidx.dst), 384 (u_long) ntohl(sav->spi))); 385 error = EPFNOSUPPORT; 386 goto bad; 387 } 388 if (skip + hlen + ralen > maxpacketsize) { 389 V_ipcompstat.ipcomps_toobig++; 390 DPRINTF(("%s: packet in IPCA %s/%08lx got too big " 391 "(len %u, max len %u)\n", __func__, 392 ipsec_address(&sav->sah->saidx.dst), 393 (u_long) ntohl(sav->spi), 394 skip + hlen + ralen, maxpacketsize)); 395 error = EMSGSIZE; 396 goto bad; 397 } 398 399 /* Update the counters */ 400 V_ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip; 401 402 m = m_unshare(m, M_NOWAIT); 403 if (m == NULL) { 404 V_ipcompstat.ipcomps_hdrops++; 405 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n", 406 __func__, ipsec_address(&sav->sah->saidx.dst), 407 (u_long) ntohl(sav->spi))); 408 error = ENOBUFS; 409 goto bad; 410 } 411 412 /* Inject IPCOMP header */ 413 mo = m_makespace(m, skip, hlen, &roff); 414 if (mo == NULL) { 415 V_ipcompstat.ipcomps_wrap++; 416 DPRINTF(("%s: IPCOMP header inject failed for IPCA %s/%08lx\n", 417 __func__, ipsec_address(&sav->sah->saidx.dst), 418 (u_long) ntohl(sav->spi))); 419 error = ENOBUFS; 420 goto bad; 421 } 422 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff); 423 424 /* Initialize the IPCOMP header */ 425 /* XXX alignment always correct? */ 426 switch (sav->sah->saidx.dst.sa.sa_family) { 427 #ifdef INET 428 case AF_INET: 429 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p; 430 break; 431 #endif /* INET */ 432 #ifdef INET6 433 case AF_INET6: 434 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt; 435 break; 436 #endif 437 } 438 ipcomp->comp_flags = 0; 439 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi)); 440 441 /* Fix Next Protocol in IPv4/IPv6 header */ 442 prot = IPPROTO_IPCOMP; 443 m_copyback(m, protoff, sizeof(u_int8_t), (u_char *) &prot); 444 445 /* Ok now, we can pass to the crypto processing */ 446 447 /* Get crypto descriptors */ 448 crp = crypto_getreq(1); 449 if (crp == NULL) { 450 V_ipcompstat.ipcomps_crypto++; 451 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__)); 452 error = ENOBUFS; 453 goto bad; 454 } 455 crdc = crp->crp_desc; 456 457 /* Compression descriptor */ 458 crdc->crd_skip = skip + hlen; 459 crdc->crd_len = m->m_pkthdr.len - (skip + hlen); 460 crdc->crd_flags = CRD_F_COMP; 461 crdc->crd_inject = skip + hlen; 462 463 /* Compression operation */ 464 crdc->crd_alg = ipcompx->type; 465 466 /* IPsec-specific opaque crypto info */ 467 tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto), 468 M_XDATA, M_NOWAIT|M_ZERO); 469 if (tc == NULL) { 470 V_ipcompstat.ipcomps_crypto++; 471 DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__)); 472 crypto_freereq(crp); 473 error = ENOBUFS; 474 goto bad; 475 } 476 477 tc->tc_isr = isr; 478 tc->tc_spi = sav->spi; 479 tc->tc_dst = sav->sah->saidx.dst; 480 tc->tc_proto = sav->sah->saidx.proto; 481 tc->tc_skip = skip + hlen; 482 483 /* Crypto operation descriptor */ 484 crp->crp_ilen = m->m_pkthdr.len; /* Total input length */ 485 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC; 486 crp->crp_buf = (caddr_t) m; 487 crp->crp_callback = ipcomp_output_cb; 488 crp->crp_opaque = (caddr_t) tc; 489 crp->crp_sid = sav->tdb_cryptoid; 490 491 return crypto_dispatch(crp); 492 bad: 493 if (m) 494 m_freem(m); 495 return (error); 496 } 497 498 /* 499 * IPComp output callback from the crypto driver. 500 */ 501 static int 502 ipcomp_output_cb(struct cryptop *crp) 503 { 504 INIT_VNET_IPSEC(curvnet); 505 struct tdb_crypto *tc; 506 struct ipsecrequest *isr; 507 struct secasvar *sav; 508 struct mbuf *m; 509 int error, skip, rlen; 510 511 tc = (struct tdb_crypto *) crp->crp_opaque; 512 IPSEC_ASSERT(tc != NULL, ("null opaque data area!")); 513 m = (struct mbuf *) crp->crp_buf; 514 skip = tc->tc_skip; 515 rlen = crp->crp_ilen - skip; 516 517 isr = tc->tc_isr; 518 IPSECREQUEST_LOCK(isr); 519 sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi); 520 if (sav == NULL) { 521 V_ipcompstat.ipcomps_notdb++; 522 DPRINTF(("%s: SA expired while in crypto\n", __func__)); 523 error = ENOBUFS; /*XXX*/ 524 goto bad; 525 } 526 IPSEC_ASSERT(isr->sav == sav, ("SA changed\n")); 527 528 /* Check for crypto errors */ 529 if (crp->crp_etype) { 530 /* Reset session ID */ 531 if (sav->tdb_cryptoid != 0) 532 sav->tdb_cryptoid = crp->crp_sid; 533 534 if (crp->crp_etype == EAGAIN) { 535 KEY_FREESAV(&sav); 536 IPSECREQUEST_UNLOCK(isr); 537 error = crypto_dispatch(crp); 538 return error; 539 } 540 V_ipcompstat.ipcomps_noxform++; 541 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype)); 542 error = crp->crp_etype; 543 goto bad; 544 } 545 /* Shouldn't happen... */ 546 if (m == NULL) { 547 V_ipcompstat.ipcomps_crypto++; 548 DPRINTF(("%s: bogus return buffer from crypto\n", __func__)); 549 error = EINVAL; 550 goto bad; 551 } 552 V_ipcompstat.ipcomps_hist[sav->alg_comp]++; 553 554 if (rlen > crp->crp_olen) { 555 /* Adjust the length in the IP header */ 556 switch (sav->sah->saidx.dst.sa.sa_family) { 557 #ifdef INET 558 case AF_INET: 559 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len); 560 break; 561 #endif /* INET */ 562 #ifdef INET6 563 case AF_INET6: 564 mtod(m, struct ip6_hdr *)->ip6_plen = 565 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr); 566 break; 567 #endif /* INET6 */ 568 default: 569 V_ipcompstat.ipcomps_nopf++; 570 DPRINTF(("%s: unknown/unsupported protocol " 571 "family %d, IPCA %s/%08lx\n", __func__, 572 sav->sah->saidx.dst.sa.sa_family, 573 ipsec_address(&sav->sah->saidx.dst), 574 (u_long) ntohl(sav->spi))); 575 error = EPFNOSUPPORT; 576 goto bad; 577 } 578 } else { 579 /* compression was useless, we have lost time */ 580 /* XXX add statistic */ 581 } 582 583 /* Release the crypto descriptor */ 584 free(tc, M_XDATA); 585 crypto_freereq(crp); 586 587 /* NB: m is reclaimed by ipsec_process_done. */ 588 error = ipsec_process_done(m, isr); 589 KEY_FREESAV(&sav); 590 IPSECREQUEST_UNLOCK(isr); 591 return error; 592 bad: 593 if (sav) 594 KEY_FREESAV(&sav); 595 IPSECREQUEST_UNLOCK(isr); 596 if (m) 597 m_freem(m); 598 free(tc, M_XDATA); 599 crypto_freereq(crp); 600 return error; 601 } 602 603 static struct xformsw ipcomp_xformsw = { 604 XF_IPCOMP, XFT_COMP, "IPcomp", 605 ipcomp_init, ipcomp_zeroize, ipcomp_input, 606 ipcomp_output 607 }; 608 609 static void 610 ipcomp_attach(void) 611 { 612 613 xform_register(&ipcomp_xformsw); 614 #ifndef VIMAGE_GLOBALS 615 vnet_mod_register(&vnet_ipcomp_modinfo); 616 #else 617 ipcomp_iattach(NULL); 618 #endif 619 } 620 621 static int 622 ipcomp_iattach(const void *unused __unused) 623 { 624 INIT_VNET_IPSEC(curvnet); 625 626 V_ipcomp_enable = 0; 627 return (0); 628 } 629 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipcomp_attach, NULL); 630