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 1.10 2006/10/12 01:32:51 hsu 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 #include <sys/thread2.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 <netproto/ipsec/ipsec.h>
  52 #include <netproto/ipsec/xform.h>
  53
  54 #ifdef INET6
  55 #include <netinet/ip6.h>
  56 #include <netproto/ipsec/ipsec6.h>
  57 #endif
  58
  59 #include <netproto/ipsec/ipcomp.h>
  60 #include <netproto/ipsec/ipcomp_var.h>
  61
  62 #include <netproto/ipsec/key.h>
  63 #include <netproto/ipsec/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(("ipcomp_init: unsupported compression algorithm %d\n",
 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         struct ipcomp *ipcomp;
 143         caddr_t addr;
 144         int hlen = IPCOMP_HLENGTH;
 145
 146         /*
 147          * Check that the next header of the IPComp is not IPComp again, before
 148          * doing any real work.  Given it is not possible to do double
 149          * compression it means someone is playing tricks on us.
 150          */
 151         if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
 152                 ipcompstat.ipcomps_hdrops++;            /*XXX*/
 153                 DPRINTF(("%s: m_pullup failed\n", __func__));
 154                 return (ENOBUFS);
 155         }
 156         addr = (caddr_t) mtod(m, struct ip *) + skip;
 157         ipcomp = (struct ipcomp *)addr;
 158         if (ipcomp->comp_nxt == IPPROTO_IPCOMP) {
 159                 m_freem(m);
 160                 ipcompstat.ipcomps_pdrops++;    /* XXX have our own stats? */
 161                 DPRINTF(("%s: recursive compression detected\n", __func__));
 162                 return (EINVAL);
 163         }
 164
 165         /* Get crypto descriptors */
 166         crp = crypto_getreq(1);
 167         if (crp == NULL) {
 168                 m_freem(m);
 169                 DPRINTF(("ipcomp_input: no crypto descriptors\n"));
 170                 ipcompstat.ipcomps_crypto++;
 171                 return ENOBUFS;
 172         }
 173         /* Get IPsec-specific opaque pointer */
 174         tc = kmalloc(sizeof (*tc), M_XDATA,
 175                     M_INTWAIT | M_ZERO | M_NULLOK);
 176         if (tc == NULL) {
 177                 m_freem(m);
 178                 crypto_freereq(crp);
 179                 DPRINTF(("ipcomp_input: cannot allocate tdb_crypto\n"));
 180                 ipcompstat.ipcomps_crypto++;
 181                 return ENOBUFS;
 182         }
 183         crdc = crp->crp_desc;
 184
 185         crdc->crd_skip = skip + hlen;
 186         crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
 187         crdc->crd_inject = skip;
 188
 189         tc->tc_ptr = 0;
 190
 191         /* Decompression operation */
 192         crdc->crd_alg = sav->tdb_compalgxform->type;
 193
 194         /* Crypto operation descriptor */
 195         crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
 196         crp->crp_flags = CRYPTO_F_IMBUF;
 197         crp->crp_buf = (caddr_t) m;
 198         crp->crp_callback = ipcomp_input_cb;
 199         crp->crp_sid = sav->tdb_cryptoid;
 200         crp->crp_opaque = (caddr_t) tc;
 201
 202         /* These are passed as-is to the callback */
 203         tc->tc_spi = sav->spi;
 204         tc->tc_dst = sav->sah->saidx.dst;
 205         tc->tc_proto = sav->sah->saidx.proto;
 206         tc->tc_protoff = protoff;
 207         tc->tc_skip = skip;
 208
 209         return crypto_dispatch(crp);
 210 }
 211
 212 #ifdef INET6
 213 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do {              \
 214         if (saidx->dst.sa.sa_family == AF_INET6) {                           \
 215                 error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \
 216         } else {                                                             \
 217                 error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \
 218         }                                                                    \
 219 } while (0)
 220 #else
 221 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag)                   \
 222         (error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag))
 223 #endif
 224
 225 /*
 226  * IPComp input callback from the crypto driver.
 227  */
 228 static int
 229 ipcomp_input_cb(struct cryptop *crp)
 230 {
 231         struct cryptodesc *crd;
 232         struct tdb_crypto *tc;
 233         int skip, protoff;
 234         struct mtag *mtag;
 235         struct mbuf *m;
 236         struct secasvar *sav;
 237         struct secasindex *saidx;
 238         int hlen = IPCOMP_HLENGTH, error, clen;
 239         u_int8_t nproto;
 240         caddr_t addr;
 241
 242         crd = crp->crp_desc;
 243
 244         tc = (struct tdb_crypto *) crp->crp_opaque;
 245         KASSERT(tc != NULL, ("ipcomp_input_cb: null opaque crypto data area!"));
 246         skip = tc->tc_skip;
 247         protoff = tc->tc_protoff;
 248         mtag = (struct mtag *) tc->tc_ptr;
 249         m = (struct mbuf *) crp->crp_buf;
 250
 251         crit_enter();
 252
 253         sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
 254         if (sav == NULL) {
 255                 ipcompstat.ipcomps_notdb++;
 256                 DPRINTF(("ipcomp_input_cb: SA expired while in crypto\n"));
 257                 error = ENOBUFS;                /*XXX*/
 258                 goto bad;
 259         }
 260
 261         saidx = &sav->sah->saidx;
 262         KASSERT(saidx->dst.sa.sa_family == AF_INET ||
 263                 saidx->dst.sa.sa_family == AF_INET6,
 264                 ("ah_input_cb: unexpected protocol family %u",
 265                  saidx->dst.sa.sa_family));
 266
 267         /* Check for crypto errors */
 268         if (crp->crp_etype) {
 269                 /* Reset the session ID */
 270                 if (sav->tdb_cryptoid != 0)
 271                         sav->tdb_cryptoid = crp->crp_sid;
 272
 273                 if (crp->crp_etype == EAGAIN) {
 274                         KEY_FREESAV(&sav);
 275                         crit_exit();
 276                         return crypto_dispatch(crp);
 277                 }
 278
 279                 ipcompstat.ipcomps_noxform++;
 280                 DPRINTF(("ipcomp_input_cb: crypto error %d\n", crp->crp_etype));
 281                 error = crp->crp_etype;
 282                 goto bad;
 283         }
 284         /* Shouldn't happen... */
 285         if (m == NULL) {
 286                 ipcompstat.ipcomps_crypto++;
 287                 DPRINTF(("ipcomp_input_cb: null mbuf returned from crypto\n"));
 288                 error = EINVAL;
 289                 goto bad;
 290         }
 291         ipcompstat.ipcomps_hist[sav->alg_comp]++;
 292
 293         clen = crp->crp_olen;           /* Length of data after processing */
 294
 295         /* Release the crypto descriptors */
 296         kfree(tc, M_XDATA), tc = NULL;
 297         crypto_freereq(crp), crp = NULL;
 298
 299         /* In case it's not done already, adjust the size of the mbuf chain */
 300         m->m_pkthdr.len = clen + hlen + skip;
 301
 302         if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) {
 303                 ipcompstat.ipcomps_hdrops++;            /*XXX*/
 304                 DPRINTF(("ipcomp_input_cb: m_pullup failed\n"));
 305                 error = EINVAL;                         /*XXX*/
 306                 goto bad;
 307         }
 308
 309         /* Keep the next protocol field */
 310         addr = (caddr_t) mtod(m, struct ip *) + skip;
 311         nproto = ((struct ipcomp *) addr)->comp_nxt;
 312
 313         /* Remove the IPCOMP header */
 314         error = m_striphdr(m, skip, hlen);
 315         if (error) {
 316                 ipcompstat.ipcomps_hdrops++;
 317                 DPRINTF(("ipcomp_input_cb: bad mbuf chain, IPCA %s/%08lx\n",
 318                          ipsec_address(&sav->sah->saidx.dst),
 319                          (u_long) ntohl(sav->spi)));
 320                 goto bad;
 321         }
 322
 323         /* Restore the Next Protocol field */
 324         m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
 325
 326         IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, NULL);
 327
 328         KEY_FREESAV(&sav);
 329         crit_exit();
 330         return error;
 331 bad:
 332         if (sav)
 333                 KEY_FREESAV(&sav);
 334         crit_exit();
 335         if (m)
 336                 m_freem(m);
 337         if (tc != NULL)
 338                 kfree(tc, M_XDATA);
 339         if (crp)
 340                 crypto_freereq(crp);
 341         return error;
 342 }
 343
 344 /*
 345  * IPComp output routine, called by ipsec[46]_process_packet()
 346  */
 347 static int
 348 ipcomp_output(
 349         struct mbuf *m,
 350         struct ipsecrequest *isr,
 351         struct mbuf **mp,
 352         int skip,
 353         int protoff
 354 )
 355 {
 356         struct secasvar *sav;
 357         struct comp_algo *ipcompx;
 358         int error, ralen, hlen, maxpacketsize, roff;
 359         u_int8_t prot;
 360         struct cryptodesc *crdc;
 361         struct cryptop *crp;
 362         struct tdb_crypto *tc;
 363         struct mbuf *mo;
 364         struct ipcomp *ipcomp;
 365
 366         sav = isr->sav;
 367         KASSERT(sav != NULL, ("ipcomp_output: null SA"));
 368         ipcompx = sav->tdb_compalgxform;
 369         KASSERT(ipcompx != NULL, ("ipcomp_output: null compression xform"));
 370
 371         ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
 372         hlen = IPCOMP_HLENGTH;
 373
 374         ipcompstat.ipcomps_output++;
 375
 376         /* Check for maximum packet size violations. */
 377         switch (sav->sah->saidx.dst.sa.sa_family) {
 378 #ifdef INET
 379         case AF_INET:
 380                 maxpacketsize =  IP_MAXPACKET;
 381                 break;
 382 #endif /* INET */
 383 #ifdef INET6
 384         case AF_INET6:
 385                 maxpacketsize =  IPV6_MAXPACKET;
 386                 break;
 387 #endif /* INET6 */
 388         default:
 389                 ipcompstat.ipcomps_nopf++;
 390                 DPRINTF(("ipcomp_output: unknown/unsupported protocol family %d"
 391                     ", IPCA %s/%08lx\n",
 392                     sav->sah->saidx.dst.sa.sa_family,
 393                     ipsec_address(&sav->sah->saidx.dst),
 394                     (u_long) ntohl(sav->spi)));
 395                 error = EPFNOSUPPORT;
 396                 goto bad;
 397         }
 398         if (skip + hlen + ralen > maxpacketsize) {
 399                 ipcompstat.ipcomps_toobig++;
 400                 DPRINTF(("ipcomp_output: packet in IPCA %s/%08lx got too big "
 401                     "(len %u, max len %u)\n",
 402                     ipsec_address(&sav->sah->saidx.dst),
 403                     (u_long) ntohl(sav->spi),
 404                     skip + hlen + ralen, maxpacketsize));
 405                 error = EMSGSIZE;
 406                 goto bad;
 407         }
 408
 409         /* Update the counters */
 410         ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip;
 411
 412         m = m_clone(m);
 413         if (m == NULL) {
 414                 ipcompstat.ipcomps_hdrops++;
 415                 DPRINTF(("ipcomp_output: cannot clone mbuf chain, IPCA %s/%08lx\n",
 416                     ipsec_address(&sav->sah->saidx.dst),
 417                     (u_long) ntohl(sav->spi)));
 418                 error = ENOBUFS;
 419                 goto bad;
 420         }
 421
 422         /* Inject IPCOMP header */
 423         mo = m_makespace(m, skip, hlen, &roff);
 424         if (mo == NULL) {
 425                 ipcompstat.ipcomps_wrap++;
 426                 DPRINTF(("ipcomp_output: failed to inject IPCOMP header for "
 427                     "IPCA %s/%08lx\n",
 428                     ipsec_address(&sav->sah->saidx.dst),
 429                     (u_long) ntohl(sav->spi)));
 430                 error = ENOBUFS;
 431                 goto bad;
 432         }
 433         ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
 434
 435         /* Initialize the IPCOMP header */
 436         /* XXX alignment always correct? */
 437         switch (sav->sah->saidx.dst.sa.sa_family) {
 438 #ifdef INET
 439         case AF_INET:
 440                 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
 441                 break;
 442 #endif /* INET */
 443 #ifdef INET6
 444         case AF_INET6:
 445                 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
 446                 break;
 447 #endif
 448         }
 449         ipcomp->comp_flags = 0;
 450         ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
 451
 452         /* Fix Next Protocol in IPv4/IPv6 header */
 453         prot = IPPROTO_IPCOMP;
 454         m_copyback(m, protoff, sizeof(u_int8_t), (u_char *) &prot);
 455
 456         /* Ok now, we can pass to the crypto processing */
 457
 458         /* Get crypto descriptors */
 459         crp = crypto_getreq(1);
 460         if (crp == NULL) {
 461                 ipcompstat.ipcomps_crypto++;
 462                 DPRINTF(("ipcomp_output: failed to acquire crypto descriptor\n"));
 463                 error = ENOBUFS;
 464                 goto bad;
 465         }
 466         crdc = crp->crp_desc;
 467
 468         /* Compression descriptor */
 469         crdc->crd_skip = skip + hlen;
 470         crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
 471         crdc->crd_flags = CRD_F_COMP;
 472         crdc->crd_inject = skip + hlen;
 473
 474         /* Compression operation */
 475         crdc->crd_alg = ipcompx->type;
 476
 477         /* IPsec-specific opaque crypto info */
 478         tc = kmalloc(sizeof(struct tdb_crypto),
 479                     M_XDATA, M_INTWAIT | M_ZERO | M_NULLOK);
 480         if (tc == NULL) {
 481                 ipcompstat.ipcomps_crypto++;
 482                 DPRINTF(("ipcomp_output: failed to allocate tdb_crypto\n"));
 483                 crypto_freereq(crp);
 484                 error = ENOBUFS;
 485                 goto bad;
 486         }
 487
 488         tc->tc_isr = isr;
 489         tc->tc_spi = sav->spi;
 490         tc->tc_dst = sav->sah->saidx.dst;
 491         tc->tc_proto = sav->sah->saidx.proto;
 492         tc->tc_skip = skip + hlen;
 493
 494         /* Crypto operation descriptor */
 495         crp->crp_ilen = m->m_pkthdr.len;        /* Total input length */
 496         crp->crp_flags = CRYPTO_F_IMBUF;
 497         crp->crp_buf = (caddr_t) m;
 498         crp->crp_callback = ipcomp_output_cb;
 499         crp->crp_opaque = (caddr_t) tc;
 500         crp->crp_sid = sav->tdb_cryptoid;
 501
 502         return crypto_dispatch(crp);
 503 bad:
 504         if (m)
 505                 m_freem(m);
 506         return (error);
 507 }
 508
 509 /*
 510  * IPComp output callback from the crypto driver.
 511  */
 512 static int
 513 ipcomp_output_cb(struct cryptop *crp)
 514 {
 515         struct tdb_crypto *tc;
 516         struct ipsecrequest *isr;
 517         struct secasvar *sav;
 518         struct mbuf *m;
 519         int error, skip, rlen;
 520
 521         tc = (struct tdb_crypto *) crp->crp_opaque;
 522         KASSERT(tc != NULL, ("ipcomp_output_cb: null opaque data area!"));
 523         m = (struct mbuf *) crp->crp_buf;
 524         skip = tc->tc_skip;
 525         rlen = crp->crp_ilen - skip;
 526
 527         crit_enter();
 528
 529         isr = tc->tc_isr;
 530         sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
 531         if (sav == NULL) {
 532                 ipcompstat.ipcomps_notdb++;
 533                 DPRINTF(("ipcomp_output_cb: SA expired while in crypto\n"));
 534                 error = ENOBUFS;                /*XXX*/
 535                 goto bad;
 536         }
 537         KASSERT(isr->sav == sav, ("ipcomp_output_cb: SA changed\n"));
 538
 539         /* Check for crypto errors */
 540         if (crp->crp_etype) {
 541                 /* Reset session ID */
 542                 if (sav->tdb_cryptoid != 0)
 543                         sav->tdb_cryptoid = crp->crp_sid;
 544
 545                 if (crp->crp_etype == EAGAIN) {
 546                         KEY_FREESAV(&sav);
 547                         crit_exit();
 548                         return crypto_dispatch(crp);
 549                 }
 550                 ipcompstat.ipcomps_noxform++;
 551                 DPRINTF(("ipcomp_output_cb: crypto error %d\n", crp->crp_etype));
 552                 error = crp->crp_etype;
 553                 goto bad;
 554         }
 555         /* Shouldn't happen... */
 556         if (m == NULL) {
 557                 ipcompstat.ipcomps_crypto++;
 558                 DPRINTF(("ipcomp_output_cb: bogus return buffer from crypto\n"));
 559                 error = EINVAL;
 560                 goto bad;
 561         }
 562         ipcompstat.ipcomps_hist[sav->alg_comp]++;
 563
 564         if (rlen > crp->crp_olen) {
 565                 /* Adjust the length in the IP header */
 566                 switch (sav->sah->saidx.dst.sa.sa_family) {
 567 #ifdef INET
 568                 case AF_INET:
 569                         mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
 570                         break;
 571 #endif /* INET */
 572 #ifdef INET6
 573                 case AF_INET6:
 574                         mtod(m, struct ip6_hdr *)->ip6_plen =
 575                                 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
 576                         break;
 577 #endif /* INET6 */
 578                 default:
 579                         ipcompstat.ipcomps_nopf++;
 580                         DPRINTF(("ipcomp_output: unknown/unsupported protocol "
 581                             "family %d, IPCA %s/%08lx\n",
 582                             sav->sah->saidx.dst.sa.sa_family,
 583                             ipsec_address(&sav->sah->saidx.dst),
 584                             (u_long) ntohl(sav->spi)));
 585                         error = EPFNOSUPPORT;
 586                         goto bad;
 587                 }
 588         } else {
 589                 /* compression was useless, we have lost time */
 590                 /* XXX add statistic */
 591         }
 592
 593         /* Release the crypto descriptor */
 594         kfree(tc, M_XDATA);
 595         crypto_freereq(crp);
 596
 597         /* NB: m is reclaimed by ipsec_process_done. */
 598         error = ipsec_process_done(m, isr);
 599         KEY_FREESAV(&sav);
 600         crit_exit();
 601         return error;
 602 bad:
 603         if (sav)
 604                 KEY_FREESAV(&sav);
 605         crit_exit();
 606         if (m)
 607                 m_freem(m);
 608         kfree(tc, M_XDATA);
 609         crypto_freereq(crp);
 610         return error;
 611 }
 612
 613 static struct xformsw ipcomp_xformsw = {
 614         XF_IPCOMP,              XFT_COMP,               "IPcomp",
 615         ipcomp_init,            ipcomp_zeroize,         ipcomp_input,
 616         ipcomp_output
 617 };
 618
 619 static void
 620 ipcomp_attach(void)
 621 {
 622         xform_register(&ipcomp_xformsw);
 623 }
 624 SYSINIT(ipcomp_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, ipcomp_attach, NULL)