sys/netproto/ipsec/xform_ipcomp.c

   1 /*      $FreeBSD: src/sys/netipsec/xform_ipcomp.c,v 1.1.4.2 2003/02/26 00:14:06 sam Exp $       */
   2 /*      $DragonFly: src/sys/netproto/ipsec/xform_ipcomp.c,v 1.3 2003/08/07 21:17:37 dillon Exp $        */
   3 /* $OpenBSD: ip_ipcomp.c,v 1.1 2001/07/05 12:08:52 jjbg Exp $ */
   4
   5 /*
   6  * Copyright (c) 2001 Jean-Jacques Bernard-Gundol (jj@wabbitt.org)
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *   notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *   notice, this list of conditions and the following disclaimer in the
  16  *   documentation and/or other materials provided with the distribution.
  17  * 3. The name of the author may not be used to endorse or promote products
  18  *   derived from this software without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 /* IP payload compression protocol (IPComp), see RFC 2393 */
  33 #include "opt_inet.h"
  34 #include "opt_inet6.h"
  35
  36 #include <sys/param.h>
  37 #include <sys/systm.h>
  38 #include <sys/mbuf.h>
  39 #include <sys/socket.h>
  40 #include <sys/kernel.h>
  41 #include <sys/protosw.h>
  42 #include <sys/sysctl.h>
  43
  44 #include <netinet/in.h>
  45 #include <netinet/in_systm.h>
  46 #include <netinet/ip.h>
  47 #include <netinet/ip_var.h>
  48
  49 #include <net/route.h>
  50 #include "ipsec.h"
  51 #include "xform.h"
  52
  53 #ifdef INET6
  54 #include <netinet/ip6.h>
  55 #include "ipsec6.h"
  56 #endif
  57
  58 #include "ipcomp.h"
  59 #include "ipcomp_var.h"
  60
  61 #include "key.h"
  62 #include "key_debug.h"
  63
  64 #include <opencrypto/cryptodev.h>
  65 #include <opencrypto/deflate.h>
  66 #include <opencrypto/xform.h>
  67
  68 int     ipcomp_enable = 0;
  69 struct  ipcompstat ipcompstat;
  70
  71 SYSCTL_DECL(_net_inet_ipcomp);
  72 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO,
  73         ipcomp_enable,  CTLFLAG_RW,     &ipcomp_enable, 0, "");
  74 SYSCTL_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS,
  75         stats,          CTLFLAG_RD,     &ipcompstat,    ipcompstat, "");
  76
  77 static int ipcomp_input_cb(struct cryptop *crp);
  78 static int ipcomp_output_cb(struct cryptop *crp);
  79
  80 struct comp_algo *
  81 ipcomp_algorithm_lookup(int alg)
  82 {
  83         if (alg >= IPCOMP_ALG_MAX)
  84                 return NULL;
  85         switch (alg) {
  86         case SADB_X_CALG_DEFLATE:
  87                 return &comp_algo_deflate;
  88         }
  89         return NULL;
  90 }
  91
  92 /*
  93  * ipcomp_init() is called when an CPI is being set up.
  94  */
  95 static int
  96 ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
  97 {
  98         struct comp_algo *tcomp;
  99         struct cryptoini cric;
 100
 101         /* NB: algorithm really comes in alg_enc and not alg_comp! */
 102         tcomp = ipcomp_algorithm_lookup(sav->alg_enc);
 103         if (tcomp == NULL) {
 104                 DPRINTF(("ipcomp_init: unsupported compression algorithm %d\n",
 105                          sav->alg_comp));
 106                 return EINVAL;
 107         }
 108         sav->alg_comp = sav->alg_enc;           /* set for doing histogram */
 109         sav->tdb_xform = xsp;
 110         sav->tdb_compalgxform = tcomp;
 111
 112         /* Initialize crypto session */
 113         bzero(&cric, sizeof (cric));
 114         cric.cri_alg = sav->tdb_compalgxform->type;
 115
 116         return crypto_newsession(&sav->tdb_cryptoid, &cric, crypto_support);
 117 }
 118
 119 /*
 120  * ipcomp_zeroize() used when IPCA is deleted
 121  */
 122 static int
 123 ipcomp_zeroize(struct secasvar *sav)
 124 {
 125         int err;
 126
 127         err = crypto_freesession(sav->tdb_cryptoid);
 128         sav->tdb_cryptoid = 0;
 129         return err;
 130 }
 131
 132 /*
 133  * ipcomp_input() gets called to uncompress an input packet
 134  */
 135 static int
 136 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
 137 {
 138         struct tdb_crypto *tc;
 139         struct cryptodesc *crdc;
 140         struct cryptop *crp;
 141         int hlen = IPCOMP_HLENGTH;
 142
 143         SPLASSERT(net, "ipcomp_input");
 144
 145         /* Get crypto descriptors */
 146         crp = crypto_getreq(1);
 147         if (crp == NULL) {
 148                 m_freem(m);
 149                 DPRINTF(("ipcomp_input: no crypto descriptors\n"));
 150                 ipcompstat.ipcomps_crypto++;
 151                 return ENOBUFS;
 152         }
 153         /* Get IPsec-specific opaque pointer */
 154         tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO);
 155         if (tc == NULL) {
 156                 m_freem(m);
 157                 crypto_freereq(crp);
 158                 DPRINTF(("ipcomp_input: cannot allocate tdb_crypto\n"));
 159                 ipcompstat.ipcomps_crypto++;
 160                 return ENOBUFS;
 161         }
 162         crdc = crp->crp_desc;
 163
 164         crdc->crd_skip = skip + hlen;
 165         crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
 166         crdc->crd_inject = skip;
 167
 168         tc->tc_ptr = 0;
 169
 170         /* Decompression operation */
 171         crdc->crd_alg = sav->tdb_compalgxform->type;
 172
 173         /* Crypto operation descriptor */
 174         crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
 175         crp->crp_flags = CRYPTO_F_IMBUF;
 176         crp->crp_buf = (caddr_t) m;
 177         crp->crp_callback = ipcomp_input_cb;
 178         crp->crp_sid = sav->tdb_cryptoid;
 179         crp->crp_opaque = (caddr_t) tc;
 180
 181         /* These are passed as-is to the callback */
 182         tc->tc_spi = sav->spi;
 183         tc->tc_dst = sav->sah->saidx.dst;
 184         tc->tc_proto = sav->sah->saidx.proto;
 185         tc->tc_protoff = protoff;
 186         tc->tc_skip = skip;
 187
 188         return crypto_dispatch(crp);
 189 }
 190
 191 #ifdef INET6
 192 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do {              \
 193         if (saidx->dst.sa.sa_family == AF_INET6) {                           \
 194                 error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \
 195         } else {                                                             \
 196                 error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \
 197         }                                                                    \
 198 } while (0)
 199 #else
 200 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag)                   \
 201         (error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag))
 202 #endif
 203
 204 /*
 205  * IPComp input callback from the crypto driver.
 206  */
 207 static int
 208 ipcomp_input_cb(struct cryptop *crp)
 209 {
 210         struct cryptodesc *crd;
 211         struct tdb_crypto *tc;
 212         int skip, protoff;
 213         struct mtag *mtag;
 214         struct mbuf *m;
 215         struct secasvar *sav;
 216         struct secasindex *saidx;
 217         int s, hlen = IPCOMP_HLENGTH, error, clen;
 218         u_int8_t nproto;
 219         caddr_t addr;
 220
 221         crd = crp->crp_desc;
 222
 223         tc = (struct tdb_crypto *) crp->crp_opaque;
 224         KASSERT(tc != NULL, ("ipcomp_input_cb: null opaque crypto data area!"));
 225         skip = tc->tc_skip;
 226         protoff = tc->tc_protoff;
 227         mtag = (struct mtag *) tc->tc_ptr;
 228         m = (struct mbuf *) crp->crp_buf;
 229
 230         s = splnet();
 231
 232         sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
 233         if (sav == NULL) {
 234                 ipcompstat.ipcomps_notdb++;
 235                 DPRINTF(("ipcomp_input_cb: SA expired while in crypto\n"));
 236                 error = ENOBUFS;                /*XXX*/
 237                 goto bad;
 238         }
 239
 240         saidx = &sav->sah->saidx;
 241         KASSERT(saidx->dst.sa.sa_family == AF_INET ||
 242                 saidx->dst.sa.sa_family == AF_INET6,
 243                 ("ah_input_cb: unexpected protocol family %u",
 244                  saidx->dst.sa.sa_family));
 245
 246         /* Check for crypto errors */
 247         if (crp->crp_etype) {
 248                 /* Reset the session ID */
 249                 if (sav->tdb_cryptoid != 0)
 250                         sav->tdb_cryptoid = crp->crp_sid;
 251
 252                 if (crp->crp_etype == EAGAIN) {
 253                         KEY_FREESAV(&sav);
 254                         splx(s);
 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         splx(s);
 309         return error;
 310 bad:
 311         if (sav)
 312                 KEY_FREESAV(&sav);
 313         splx(s);
 314         if (m)
 315                 m_freem(m);
 316         if (tc != NULL)
 317                 free(tc, M_XDATA);
 318         if (crp)
 319                 crypto_freereq(crp);
 320         return error;
 321 }
 322
 323 /*
 324  * IPComp output routine, called by ipsec[46]_process_packet()
 325  */
 326 static int
 327 ipcomp_output(
 328         struct mbuf *m,
 329         struct ipsecrequest *isr,
 330         struct mbuf **mp,
 331         int skip,
 332         int protoff
 333 )
 334 {
 335         struct secasvar *sav;
 336         struct comp_algo *ipcompx;
 337         int error, ralen, hlen, maxpacketsize, roff;
 338         u_int8_t prot;
 339         struct cryptodesc *crdc;
 340         struct cryptop *crp;
 341         struct tdb_crypto *tc;
 342         struct mbuf *mo;
 343         struct ipcomp *ipcomp;
 344
 345         SPLASSERT(net, "ipcomp_output");
 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;
 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);
 484 bad:
 485         if (m)
 486                 m_freem(m);
 487         return (error);
 488 }
 489
 490 /*
 491  * IPComp output callback from the crypto driver.
 492  */
 493 static int
 494 ipcomp_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 s, 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         s = splnet();
 509
 510         isr = tc->tc_isr;
 511         sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
 512         if (sav == NULL) {
 513                 ipcompstat.ipcomps_notdb++;
 514                 DPRINTF(("ipcomp_output_cb: SA expired while in crypto\n"));
 515                 error = ENOBUFS;                /*XXX*/
 516                 goto bad;
 517         }
 518         KASSERT(isr->sav == sav, ("ipcomp_output_cb: SA changed\n"));
 519
 520         /* Check for crypto errors */
 521         if (crp->crp_etype) {
 522                 /* Reset session ID */
 523                 if (sav->tdb_cryptoid != 0)
 524                         sav->tdb_cryptoid = crp->crp_sid;
 525
 526                 if (crp->crp_etype == EAGAIN) {
 527                         KEY_FREESAV(&sav);
 528                         splx(s);
 529                         return crypto_dispatch(crp);
 530                 }
 531                 ipcompstat.ipcomps_noxform++;
 532                 DPRINTF(("ipcomp_output_cb: crypto error %d\n", crp->crp_etype));
 533                 error = crp->crp_etype;
 534                 goto bad;
 535         }
 536         /* Shouldn't happen... */
 537         if (m == NULL) {
 538                 ipcompstat.ipcomps_crypto++;
 539                 DPRINTF(("ipcomp_output_cb: bogus return buffer from crypto\n"));
 540                 error = EINVAL;
 541                 goto bad;
 542         }
 543         ipcompstat.ipcomps_hist[sav->alg_comp]++;
 544
 545         if (rlen > crp->crp_olen) {
 546                 /* Adjust the length in the IP header */
 547                 switch (sav->sah->saidx.dst.sa.sa_family) {
 548 #ifdef INET
 549                 case AF_INET:
 550                         mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
 551                         break;
 552 #endif /* INET */
 553 #ifdef INET6
 554                 case AF_INET6:
 555                         mtod(m, struct ip6_hdr *)->ip6_plen =
 556                                 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
 557                         break;
 558 #endif /* INET6 */
 559                 default:
 560                         ipcompstat.ipcomps_nopf++;
 561                         DPRINTF(("ipcomp_output: unknown/unsupported protocol "
 562                             "family %d, IPCA %s/%08lx\n",
 563                             sav->sah->saidx.dst.sa.sa_family,
 564                             ipsec_address(&sav->sah->saidx.dst),
 565                             (u_long) ntohl(sav->spi)));
 566                         error = EPFNOSUPPORT;
 567                         goto bad;
 568                 }
 569         } else {
 570                 /* compression was useless, we have lost time */
 571                 /* XXX add statistic */
 572         }
 573
 574         /* Release the crypto descriptor */
 575         free(tc, M_XDATA);
 576         crypto_freereq(crp);
 577
 578         /* NB: m is reclaimed by ipsec_process_done. */
 579         error = ipsec_process_done(m, isr);
 580         KEY_FREESAV(&sav);
 581         splx(s);
 582         return error;
 583 bad:
 584         if (sav)
 585                 KEY_FREESAV(&sav);
 586         splx(s);
 587         if (m)
 588                 m_freem(m);
 589         free(tc, M_XDATA);
 590         crypto_freereq(crp);
 591         return error;
 592 }
 593
 594 static struct xformsw ipcomp_xformsw = {
 595         XF_IPCOMP,              XFT_COMP,               "IPcomp",
 596         ipcomp_init,            ipcomp_zeroize,         ipcomp_input,
 597         ipcomp_output
 598 };
 599
 600 static void
 601 ipcomp_attach(void)
 602 {
 603         xform_register(&ipcomp_xformsw);
 604 }
 605 SYSINIT(ipcomp_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, ipcomp_attach, NULL)