sys/netipsec/xform_ipcomp.c

   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         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                 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                 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                 ipcompstat.ipcomps_crypto++;
 264                 DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
 265                 error = EINVAL;
 266                 goto bad;
 267         }
 268         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                 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                 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         IPSEC_SPLASSERT_SOFTNET(__func__);
 342
 343         sav = isr->sav;
 344         IPSEC_ASSERT(sav != NULL, ("null SA"));
 345         ipcompx = sav->tdb_compalgxform;
 346         IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
 347
 348         ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
 349         hlen = IPCOMP_HLENGTH;
 350
 351         ipcompstat.ipcomps_output++;
 352
 353         /* Check for maximum packet size violations. */
 354         switch (sav->sah->saidx.dst.sa.sa_family) {
 355 #ifdef INET
 356         case AF_INET:
 357                 maxpacketsize =  IP_MAXPACKET;
 358                 break;
 359 #endif /* INET */
 360 #ifdef INET6
 361         case AF_INET6:
 362                 maxpacketsize =  IPV6_MAXPACKET;
 363                 break;
 364 #endif /* INET6 */
 365         default:
 366                 ipcompstat.ipcomps_nopf++;
 367                 DPRINTF(("%s: unknown/unsupported protocol family %d, "
 368                     "IPCA %s/%08lx\n", __func__,
 369                     sav->sah->saidx.dst.sa.sa_family,
 370                     ipsec_address(&sav->sah->saidx.dst),
 371                     (u_long) ntohl(sav->spi)));
 372                 error = EPFNOSUPPORT;
 373                 goto bad;
 374         }
 375         if (skip + hlen + ralen > maxpacketsize) {
 376                 ipcompstat.ipcomps_toobig++;
 377                 DPRINTF(("%s: packet in IPCA %s/%08lx got too big "
 378                     "(len %u, max len %u)\n", __func__,
 379                     ipsec_address(&sav->sah->saidx.dst),
 380                     (u_long) ntohl(sav->spi),
 381                     skip + hlen + ralen, maxpacketsize));
 382                 error = EMSGSIZE;
 383                 goto bad;
 384         }
 385
 386         /* Update the counters */
 387         ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip;
 388
 389         m = m_unshare(m, M_NOWAIT);
 390         if (m == NULL) {
 391                 ipcompstat.ipcomps_hdrops++;
 392                 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
 393                     __func__, ipsec_address(&sav->sah->saidx.dst),
 394                     (u_long) ntohl(sav->spi)));
 395                 error = ENOBUFS;
 396                 goto bad;
 397         }
 398
 399         /* Inject IPCOMP header */
 400         mo = m_makespace(m, skip, hlen, &roff);
 401         if (mo == NULL) {
 402                 ipcompstat.ipcomps_wrap++;
 403                 DPRINTF(("%s: IPCOMP header inject failed for IPCA %s/%08lx\n",
 404                     __func__, ipsec_address(&sav->sah->saidx.dst),
 405                     (u_long) ntohl(sav->spi)));
 406                 error = ENOBUFS;
 407                 goto bad;
 408         }
 409         ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
 410
 411         /* Initialize the IPCOMP header */
 412         /* XXX alignment always correct? */
 413         switch (sav->sah->saidx.dst.sa.sa_family) {
 414 #ifdef INET
 415         case AF_INET:
 416                 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
 417                 break;
 418 #endif /* INET */
 419 #ifdef INET6
 420         case AF_INET6:
 421                 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
 422                 break;
 423 #endif
 424         }
 425         ipcomp->comp_flags = 0;
 426         ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
 427
 428         /* Fix Next Protocol in IPv4/IPv6 header */
 429         prot = IPPROTO_IPCOMP;
 430         m_copyback(m, protoff, sizeof(u_int8_t), (u_char *) &prot);
 431
 432         /* Ok now, we can pass to the crypto processing */
 433
 434         /* Get crypto descriptors */
 435         crp = crypto_getreq(1);
 436         if (crp == NULL) {
 437                 ipcompstat.ipcomps_crypto++;
 438                 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
 439                 error = ENOBUFS;
 440                 goto bad;
 441         }
 442         crdc = crp->crp_desc;
 443
 444         /* Compression descriptor */
 445         crdc->crd_skip = skip + hlen;
 446         crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
 447         crdc->crd_flags = CRD_F_COMP;
 448         crdc->crd_inject = skip + hlen;
 449
 450         /* Compression operation */
 451         crdc->crd_alg = ipcompx->type;
 452
 453         /* IPsec-specific opaque crypto info */
 454         tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto),
 455                 M_XDATA, M_NOWAIT|M_ZERO);
 456         if (tc == NULL) {
 457                 ipcompstat.ipcomps_crypto++;
 458                 DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__));
 459                 crypto_freereq(crp);
 460                 error = ENOBUFS;
 461                 goto bad;
 462         }
 463
 464         tc->tc_isr = isr;
 465         tc->tc_spi = sav->spi;
 466         tc->tc_dst = sav->sah->saidx.dst;
 467         tc->tc_proto = sav->sah->saidx.proto;
 468         tc->tc_skip = skip + hlen;
 469
 470         /* Crypto operation descriptor */
 471         crp->crp_ilen = m->m_pkthdr.len;        /* Total input length */
 472         crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
 473         crp->crp_buf = (caddr_t) m;
 474         crp->crp_callback = ipcomp_output_cb;
 475         crp->crp_opaque = (caddr_t) tc;
 476         crp->crp_sid = sav->tdb_cryptoid;
 477
 478         return crypto_dispatch(crp);
 479 bad:
 480         if (m)
 481                 m_freem(m);
 482         return (error);
 483 }
 484
 485 /*
 486  * IPComp output callback from the crypto driver.
 487  */
 488 static int
 489 ipcomp_output_cb(struct cryptop *crp)
 490 {
 491         struct tdb_crypto *tc;
 492         struct ipsecrequest *isr;
 493         struct secasvar *sav;
 494         struct mbuf *m;
 495         int error, skip, rlen;
 496
 497         tc = (struct tdb_crypto *) crp->crp_opaque;
 498         IPSEC_ASSERT(tc != NULL, ("null opaque data area!"));
 499         m = (struct mbuf *) crp->crp_buf;
 500         skip = tc->tc_skip;
 501         rlen = crp->crp_ilen - skip;
 502
 503         isr = tc->tc_isr;
 504         IPSECREQUEST_LOCK(isr);
 505         sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
 506         if (sav == NULL) {
 507                 ipcompstat.ipcomps_notdb++;
 508                 DPRINTF(("%s: SA expired while in crypto\n", __func__));
 509                 error = ENOBUFS;                /*XXX*/
 510                 goto bad;
 511         }
 512         IPSEC_ASSERT(isr->sav == sav, ("SA changed\n"));
 513
 514         /* Check for crypto errors */
 515         if (crp->crp_etype) {
 516                 /* Reset session ID */
 517                 if (sav->tdb_cryptoid != 0)
 518                         sav->tdb_cryptoid = crp->crp_sid;
 519
 520                 if (crp->crp_etype == EAGAIN) {
 521                         KEY_FREESAV(&sav);
 522                         IPSECREQUEST_UNLOCK(isr);
 523                         error = crypto_dispatch(crp);
 524                         return error;
 525                 }
 526                 ipcompstat.ipcomps_noxform++;
 527                 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
 528                 error = crp->crp_etype;
 529                 goto bad;
 530         }
 531         /* Shouldn't happen... */
 532         if (m == NULL) {
 533                 ipcompstat.ipcomps_crypto++;
 534                 DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
 535                 error = EINVAL;
 536                 goto bad;
 537         }
 538         ipcompstat.ipcomps_hist[sav->alg_comp]++;
 539
 540         if (rlen > crp->crp_olen) {
 541                 /* Adjust the length in the IP header */
 542                 switch (sav->sah->saidx.dst.sa.sa_family) {
 543 #ifdef INET
 544                 case AF_INET:
 545                         mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
 546                         break;
 547 #endif /* INET */
 548 #ifdef INET6
 549                 case AF_INET6:
 550                         mtod(m, struct ip6_hdr *)->ip6_plen =
 551                                 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
 552                         break;
 553 #endif /* INET6 */
 554                 default:
 555                         ipcompstat.ipcomps_nopf++;
 556                         DPRINTF(("%s: unknown/unsupported protocol "
 557                             "family %d, IPCA %s/%08lx\n", __func__,
 558                             sav->sah->saidx.dst.sa.sa_family,
 559                             ipsec_address(&sav->sah->saidx.dst),
 560                             (u_long) ntohl(sav->spi)));
 561                         error = EPFNOSUPPORT;
 562                         goto bad;
 563                 }
 564         } else {
 565                 /* compression was useless, we have lost time */
 566                 /* XXX add statistic */
 567         }
 568
 569         /* Release the crypto descriptor */
 570         free(tc, M_XDATA);
 571         crypto_freereq(crp);
 572
 573         /* NB: m is reclaimed by ipsec_process_done. */
 574         error = ipsec_process_done(m, isr);
 575         KEY_FREESAV(&sav);
 576         IPSECREQUEST_UNLOCK(isr);
 577         return error;
 578 bad:
 579         if (sav)
 580                 KEY_FREESAV(&sav);
 581         IPSECREQUEST_UNLOCK(isr);
 582         if (m)
 583                 m_freem(m);
 584         free(tc, M_XDATA);
 585         crypto_freereq(crp);
 586         return error;
 587 }
 588
 589 static struct xformsw ipcomp_xformsw = {
 590         XF_IPCOMP,              XFT_COMP,               "IPcomp",
 591         ipcomp_init,            ipcomp_zeroize,         ipcomp_input,
 592         ipcomp_output
 593 };
 594
 595 static void
 596 ipcomp_attach(void)
 597 {
 598         xform_register(&ipcomp_xformsw);
 599 }
 600 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipcomp_attach, NULL);