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/rwlock.h>
  41 #include <sys/socket.h>
  42 #include <sys/kernel.h>
  43 #include <sys/protosw.h>
  44 #include <sys/sysctl.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 <net/vnet.h>
  53
  54 #include <netipsec/ipsec.h>
  55 #include <netipsec/xform.h>
  56
  57 #ifdef INET6
  58 #include <netinet/ip6.h>
  59 #include <netipsec/ipsec6.h>
  60 #endif
  61
  62 #include <netipsec/ipcomp.h>
  63 #include <netipsec/ipcomp_var.h>
  64
  65 #include <netipsec/key.h>
  66 #include <netipsec/key_debug.h>
  67
  68 #include <opencrypto/cryptodev.h>
  69 #include <opencrypto/deflate.h>
  70 #include <opencrypto/xform.h>
  71
  72 VNET_DEFINE(int, ipcomp_enable) = 1;
  73 VNET_DEFINE(struct ipcompstat, ipcompstat);
  74
  75 SYSCTL_DECL(_net_inet_ipcomp);
  76 SYSCTL_VNET_INT(_net_inet_ipcomp, OID_AUTO,
  77         ipcomp_enable,  CTLFLAG_RW,     &VNET_NAME(ipcomp_enable),      0, "");
  78 SYSCTL_VNET_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS,
  79         stats,          CTLFLAG_RD,     &VNET_NAME(ipcompstat), ipcompstat, "");
  80
  81 static int ipcomp_input_cb(struct cryptop *crp);
  82 static int ipcomp_output_cb(struct cryptop *crp);
  83
  84 struct comp_algo *
  85 ipcomp_algorithm_lookup(int alg)
  86 {
  87         if (alg >= IPCOMP_ALG_MAX)
  88                 return NULL;
  89         switch (alg) {
  90         case SADB_X_CALG_DEFLATE:
  91                 return &comp_algo_deflate;
  92         }
  93         return NULL;
  94 }
  95
  96 /*
  97  * ipcomp_init() is called when an CPI is being set up.
  98  */
  99 static int
 100 ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
 101 {
 102         struct comp_algo *tcomp;
 103         struct cryptoini cric;
 104
 105         /* NB: algorithm really comes in alg_enc and not alg_comp! */
 106         tcomp = ipcomp_algorithm_lookup(sav->alg_enc);
 107         if (tcomp == NULL) {
 108                 DPRINTF(("%s: unsupported compression algorithm %d\n", __func__,
 109                          sav->alg_comp));
 110                 return EINVAL;
 111         }
 112         sav->alg_comp = sav->alg_enc;           /* set for doing histogram */
 113         sav->tdb_xform = xsp;
 114         sav->tdb_compalgxform = tcomp;
 115
 116         /* Initialize crypto session */
 117         bzero(&cric, sizeof (cric));
 118         cric.cri_alg = sav->tdb_compalgxform->type;
 119
 120         return crypto_newsession(&sav->tdb_cryptoid, &cric, V_crypto_support);
 121 }
 122
 123 /*
 124  * ipcomp_zeroize() used when IPCA is deleted
 125  */
 126 static int
 127 ipcomp_zeroize(struct secasvar *sav)
 128 {
 129         int err;
 130
 131         err = crypto_freesession(sav->tdb_cryptoid);
 132         sav->tdb_cryptoid = 0;
 133         return err;
 134 }
 135
 136 /*
 137  * ipcomp_input() gets called to uncompress an input packet
 138  */
 139 static int
 140 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
 141 {
 142         struct tdb_crypto *tc;
 143         struct cryptodesc *crdc;
 144         struct cryptop *crp;
 145         struct ipcomp *ipcomp;
 146         caddr_t addr;
 147         int hlen = IPCOMP_HLENGTH;
 148
 149         /*
 150          * Check that the next header of the IPComp is not IPComp again, before
 151          * doing any real work.  Given it is not possible to do double
 152          * compression it means someone is playing tricks on us.
 153          */
 154         if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
 155                 IPCOMPSTAT_INC(ipcomps_hdrops);         /*XXX*/
 156                 DPRINTF(("%s: m_pullup failed\n", __func__));
 157                 return (ENOBUFS);
 158         }
 159         addr = (caddr_t) mtod(m, struct ip *) + skip;
 160         ipcomp = (struct ipcomp *)addr;
 161         if (ipcomp->comp_nxt == IPPROTO_IPCOMP) {
 162                 m_freem(m);
 163                 IPCOMPSTAT_INC(ipcomps_pdrops); /* XXX have our own stats? */
 164                 DPRINTF(("%s: recursive compression detected\n", __func__));
 165                 return (EINVAL);
 166         }
 167
 168         /* Get crypto descriptors */
 169         crp = crypto_getreq(1);
 170         if (crp == NULL) {
 171                 m_freem(m);
 172                 DPRINTF(("%s: no crypto descriptors\n", __func__));
 173                 IPCOMPSTAT_INC(ipcomps_crypto);
 174                 return ENOBUFS;
 175         }
 176         /* Get IPsec-specific opaque pointer */
 177         tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO);
 178         if (tc == NULL) {
 179                 m_freem(m);
 180                 crypto_freereq(crp);
 181                 DPRINTF(("%s: cannot allocate tdb_crypto\n", __func__));
 182                 IPCOMPSTAT_INC(ipcomps_crypto);
 183                 return ENOBUFS;
 184         }
 185         crdc = crp->crp_desc;
 186
 187         crdc->crd_skip = skip + hlen;
 188         crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
 189         crdc->crd_inject = skip;
 190
 191         tc->tc_ptr = 0;
 192
 193         /* Decompression operation */
 194         crdc->crd_alg = sav->tdb_compalgxform->type;
 195
 196         /* Crypto operation descriptor */
 197         crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
 198         crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
 199         crp->crp_buf = (caddr_t) m;
 200         crp->crp_callback = ipcomp_input_cb;
 201         crp->crp_sid = sav->tdb_cryptoid;
 202         crp->crp_opaque = (caddr_t) tc;
 203
 204         /* These are passed as-is to the callback */
 205         tc->tc_spi = sav->spi;
 206         tc->tc_dst = sav->sah->saidx.dst;
 207         tc->tc_proto = sav->sah->saidx.proto;
 208         tc->tc_protoff = protoff;
 209         tc->tc_skip = skip;
 210         KEY_ADDREFSA(sav);
 211         tc->tc_sav = sav;
 212
 213         return crypto_dispatch(crp);
 214 }
 215
 216 /*
 217  * IPComp input callback from the crypto driver.
 218  */
 219 static int
 220 ipcomp_input_cb(struct cryptop *crp)
 221 {
 222         struct cryptodesc *crd;
 223         struct tdb_crypto *tc;
 224         int skip, protoff;
 225         struct mtag *mtag;
 226         struct mbuf *m;
 227         struct secasvar *sav;
 228         struct secasindex *saidx;
 229         int hlen = IPCOMP_HLENGTH, error, clen;
 230         u_int8_t nproto;
 231         caddr_t addr;
 232
 233         crd = crp->crp_desc;
 234
 235         tc = (struct tdb_crypto *) crp->crp_opaque;
 236         IPSEC_ASSERT(tc != NULL, ("null opaque crypto data area!"));
 237         skip = tc->tc_skip;
 238         protoff = tc->tc_protoff;
 239         mtag = (struct mtag *) tc->tc_ptr;
 240         m = (struct mbuf *) crp->crp_buf;
 241
 242         sav = tc->tc_sav;
 243         IPSEC_ASSERT(sav != NULL, ("null SA!"));
 244
 245         saidx = &sav->sah->saidx;
 246         IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
 247                 saidx->dst.sa.sa_family == AF_INET6,
 248                 ("unexpected protocol family %u", saidx->dst.sa.sa_family));
 249
 250         /* Check for crypto errors */
 251         if (crp->crp_etype) {
 252                 /* Reset the session ID */
 253                 if (sav->tdb_cryptoid != 0)
 254                         sav->tdb_cryptoid = crp->crp_sid;
 255
 256                 if (crp->crp_etype == EAGAIN) {
 257                         return crypto_dispatch(crp);
 258                 }
 259                 IPCOMPSTAT_INC(ipcomps_noxform);
 260                 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
 261                 error = crp->crp_etype;
 262                 goto bad;
 263         }
 264         /* Shouldn't happen... */
 265         if (m == NULL) {
 266                 IPCOMPSTAT_INC(ipcomps_crypto);
 267                 DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
 268                 error = EINVAL;
 269                 goto bad;
 270         }
 271         IPCOMPSTAT_INC(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_INC(ipcomps_hdrops);         /*XXX*/
 284                 DPRINTF(("%s: m_pullup failed\n", __func__));
 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_INC(ipcomps_hdrops);
 297                 DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__,
 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         switch (saidx->dst.sa.sa_family) {
 307 #ifdef INET6
 308         case AF_INET6:
 309                 error = ipsec6_common_input_cb(m, sav, skip, protoff, NULL);
 310                 break;
 311 #endif
 312 #ifdef INET
 313         case AF_INET:
 314                 error = ipsec4_common_input_cb(m, sav, skip, protoff, NULL);
 315                 break;
 316 #endif
 317         default:
 318                 panic("%s: Unexpected address family: %d saidx=%p", __func__,
 319                     saidx->dst.sa.sa_family, saidx);
 320         }
 321
 322         KEY_FREESAV(&sav);
 323         return error;
 324 bad:
 325         if (sav)
 326                 KEY_FREESAV(&sav);
 327         if (m)
 328                 m_freem(m);
 329         if (tc != NULL)
 330                 free(tc, M_XDATA);
 331         if (crp)
 332                 crypto_freereq(crp);
 333         return error;
 334 }
 335
 336 /*
 337  * IPComp output routine, called by ipsec[46]_process_packet()
 338  */
 339 static int
 340 ipcomp_output(
 341         struct mbuf *m,
 342         struct ipsecrequest *isr,
 343         struct mbuf **mp,
 344         int skip,
 345         int protoff
 346 )
 347 {
 348         struct secasvar *sav;
 349         struct comp_algo *ipcompx;
 350         int error, ralen, maxpacketsize;
 351         struct cryptodesc *crdc;
 352         struct cryptop *crp;
 353         struct tdb_crypto *tc;
 354
 355         sav = isr->sav;
 356         IPSEC_ASSERT(sav != NULL, ("null SA"));
 357         ipcompx = sav->tdb_compalgxform;
 358         IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
 359
 360         /*
 361          * Do not touch the packet in case our payload to compress
 362          * is lower than the minimal threshold of the compression
 363          * alogrithm.  We will just send out the data uncompressed.
 364          * See RFC 3173, 2.2. Non-Expansion Policy.
 365          */
 366         if (m->m_pkthdr.len <= ipcompx->minlen) {
 367                 IPCOMPSTAT_INC(ipcomps_threshold);
 368                 return ipsec_process_done(m, isr);
 369         }
 370
 371         ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
 372         IPCOMPSTAT_INC(ipcomps_output);
 373
 374         /* Check for maximum packet size violations. */
 375         switch (sav->sah->saidx.dst.sa.sa_family) {
 376 #ifdef INET
 377         case AF_INET:
 378                 maxpacketsize = IP_MAXPACKET;
 379                 break;
 380 #endif /* INET */
 381 #ifdef INET6
 382         case AF_INET6:
 383                 maxpacketsize = IPV6_MAXPACKET;
 384                 break;
 385 #endif /* INET6 */
 386         default:
 387                 IPCOMPSTAT_INC(ipcomps_nopf);
 388                 DPRINTF(("%s: unknown/unsupported protocol family %d, "
 389                     "IPCA %s/%08lx\n", __func__,
 390                     sav->sah->saidx.dst.sa.sa_family,
 391                     ipsec_address(&sav->sah->saidx.dst),
 392                     (u_long) ntohl(sav->spi)));
 393                 error = EPFNOSUPPORT;
 394                 goto bad;
 395         }
 396         if (ralen + skip + IPCOMP_HLENGTH > maxpacketsize) {
 397                 IPCOMPSTAT_INC(ipcomps_toobig);
 398                 DPRINTF(("%s: packet in IPCA %s/%08lx got too big "
 399                     "(len %u, max len %u)\n", __func__,
 400                     ipsec_address(&sav->sah->saidx.dst),
 401                     (u_long) ntohl(sav->spi),
 402                     ralen + skip + IPCOMP_HLENGTH, maxpacketsize));
 403                 error = EMSGSIZE;
 404                 goto bad;
 405         }
 406
 407         /* Update the counters */
 408         IPCOMPSTAT_ADD(ipcomps_obytes, m->m_pkthdr.len - skip);
 409
 410         m = m_unshare(m, M_NOWAIT);
 411         if (m == NULL) {
 412                 IPCOMPSTAT_INC(ipcomps_hdrops);
 413                 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
 414                     __func__, ipsec_address(&sav->sah->saidx.dst),
 415                     (u_long) ntohl(sav->spi)));
 416                 error = ENOBUFS;
 417                 goto bad;
 418         }
 419
 420         /* Ok now, we can pass to the crypto processing. */
 421
 422         /* Get crypto descriptors */
 423         crp = crypto_getreq(1);
 424         if (crp == NULL) {
 425                 IPCOMPSTAT_INC(ipcomps_crypto);
 426                 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
 427                 error = ENOBUFS;
 428                 goto bad;
 429         }
 430         crdc = crp->crp_desc;
 431
 432         /* Compression descriptor */
 433         crdc->crd_skip = skip;
 434         crdc->crd_len = ralen;
 435         crdc->crd_flags = CRD_F_COMP;
 436         crdc->crd_inject = skip;
 437
 438         /* Compression operation */
 439         crdc->crd_alg = ipcompx->type;
 440
 441         /* IPsec-specific opaque crypto info */
 442         tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto),
 443                 M_XDATA, M_NOWAIT|M_ZERO);
 444         if (tc == NULL) {
 445                 IPCOMPSTAT_INC(ipcomps_crypto);
 446                 DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__));
 447                 crypto_freereq(crp);
 448                 error = ENOBUFS;
 449                 goto bad;
 450         }
 451
 452         tc->tc_isr = isr;
 453         KEY_ADDREFSA(sav);
 454         tc->tc_sav = sav;
 455         tc->tc_spi = sav->spi;
 456         tc->tc_dst = sav->sah->saidx.dst;
 457         tc->tc_proto = sav->sah->saidx.proto;
 458         tc->tc_protoff = protoff;
 459         tc->tc_skip = skip;
 460
 461         /* Crypto operation descriptor */
 462         crp->crp_ilen = m->m_pkthdr.len;        /* Total input length */
 463         crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
 464         crp->crp_buf = (caddr_t) m;
 465         crp->crp_callback = ipcomp_output_cb;
 466         crp->crp_opaque = (caddr_t) tc;
 467         crp->crp_sid = sav->tdb_cryptoid;
 468
 469         return crypto_dispatch(crp);
 470 bad:
 471         if (m)
 472                 m_freem(m);
 473         return (error);
 474 }
 475
 476 /*
 477  * IPComp output callback from the crypto driver.
 478  */
 479 static int
 480 ipcomp_output_cb(struct cryptop *crp)
 481 {
 482         struct tdb_crypto *tc;
 483         struct ipsecrequest *isr;
 484         struct secasvar *sav;
 485         struct mbuf *m;
 486         int error, skip;
 487
 488         tc = (struct tdb_crypto *) crp->crp_opaque;
 489         IPSEC_ASSERT(tc != NULL, ("null opaque data area!"));
 490         m = (struct mbuf *) crp->crp_buf;
 491         skip = tc->tc_skip;
 492
 493         isr = tc->tc_isr;
 494         IPSECREQUEST_LOCK(isr);
 495         sav = tc->tc_sav;
 496         /* With the isr lock released SA pointer can be updated. */
 497         if (sav != isr->sav) {
 498                 IPCOMPSTAT_INC(ipcomps_notdb);
 499                 DPRINTF(("%s: SA expired while in crypto\n", __func__));
 500                 error = ENOBUFS;                /*XXX*/
 501                 goto bad;
 502         }
 503
 504         /* Check for crypto errors */
 505         if (crp->crp_etype) {
 506                 /* Reset the session ID */
 507                 if (sav->tdb_cryptoid != 0)
 508                         sav->tdb_cryptoid = crp->crp_sid;
 509
 510                 if (crp->crp_etype == EAGAIN) {
 511                         IPSECREQUEST_UNLOCK(isr);
 512                         return crypto_dispatch(crp);
 513                 }
 514                 IPCOMPSTAT_INC(ipcomps_noxform);
 515                 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
 516                 error = crp->crp_etype;
 517                 goto bad;
 518         }
 519         /* Shouldn't happen... */
 520         if (m == NULL) {
 521                 IPCOMPSTAT_INC(ipcomps_crypto);
 522                 DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
 523                 error = EINVAL;
 524                 goto bad;
 525         }
 526         IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
 527
 528         if (crp->crp_ilen - skip > crp->crp_olen) {
 529                 struct mbuf *mo;
 530                 struct ipcomp *ipcomp;
 531                 int roff;
 532                 uint8_t prot;
 533
 534                 /* Compression helped, inject IPCOMP header. */
 535                 mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
 536                 if (mo == NULL) {
 537                         IPCOMPSTAT_INC(ipcomps_wrap);
 538                         DPRINTF(("%s: IPCOMP header inject failed for IPCA %s/%08lx\n",
 539                             __func__, ipsec_address(&sav->sah->saidx.dst),
 540                             (u_long) ntohl(sav->spi)));
 541                         error = ENOBUFS;
 542                         goto bad;
 543                 }
 544                 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
 545
 546                 /* Initialize the IPCOMP header */
 547                 /* XXX alignment always correct? */
 548                 switch (sav->sah->saidx.dst.sa.sa_family) {
 549 #ifdef INET
 550                 case AF_INET:
 551                         ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
 552                         break;
 553 #endif /* INET */
 554 #ifdef INET6
 555                 case AF_INET6:
 556                         ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
 557                         break;
 558 #endif
 559                 }
 560                 ipcomp->comp_flags = 0;
 561                 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
 562
 563                 /* Fix Next Protocol in IPv4/IPv6 header */
 564                 prot = IPPROTO_IPCOMP;
 565                 m_copyback(m, tc->tc_protoff, sizeof(u_int8_t),
 566                     (u_char *)&prot);
 567
 568                 /* Adjust the length in the IP header */
 569                 switch (sav->sah->saidx.dst.sa.sa_family) {
 570 #ifdef INET
 571                 case AF_INET:
 572                         mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
 573                         break;
 574 #endif /* INET */
 575 #ifdef INET6
 576                 case AF_INET6:
 577                         mtod(m, struct ip6_hdr *)->ip6_plen =
 578                                 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
 579                         break;
 580 #endif /* INET6 */
 581                 default:
 582                         IPCOMPSTAT_INC(ipcomps_nopf);
 583                         DPRINTF(("%s: unknown/unsupported protocol "
 584                             "family %d, IPCA %s/%08lx\n", __func__,
 585                             sav->sah->saidx.dst.sa.sa_family,
 586                             ipsec_address(&sav->sah->saidx.dst),
 587                             (u_long) ntohl(sav->spi)));
 588                         error = EPFNOSUPPORT;
 589                         goto bad;
 590                 }
 591         } else {
 592                 /* Compression was useless, we have lost time. */
 593                 IPCOMPSTAT_INC(ipcomps_uncompr);
 594                 DPRINTF(("%s: compressions was useless %d - %d <= %d\n",
 595                     __func__, crp->crp_ilen, skip, crp->crp_olen));
 596                 /* XXX remember state to not compress the next couple
 597                  *     of packets, RFC 3173, 2.2. Non-Expansion Policy */
 598         }
 599
 600         /* Release the crypto descriptor */
 601         free(tc, M_XDATA);
 602         crypto_freereq(crp);
 603
 604         /* NB: m is reclaimed by ipsec_process_done. */
 605         error = ipsec_process_done(m, isr);
 606         KEY_FREESAV(&sav);
 607         IPSECREQUEST_UNLOCK(isr);
 608         return error;
 609 bad:
 610         if (sav)
 611                 KEY_FREESAV(&sav);
 612         IPSECREQUEST_UNLOCK(isr);
 613         if (m)
 614                 m_freem(m);
 615         free(tc, M_XDATA);
 616         crypto_freereq(crp);
 617         return error;
 618 }
 619
 620 static struct xformsw ipcomp_xformsw = {
 621         XF_IPCOMP,              XFT_COMP,               "IPcomp",
 622         ipcomp_init,            ipcomp_zeroize,         ipcomp_input,
 623         ipcomp_output
 624 };
 625
 626 static void
 627 ipcomp_attach(void)
 628 {
 629
 630         xform_register(&ipcomp_xformsw);
 631 }
 632
 633 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipcomp_attach, NULL);
 634
 635 static void
 636 vnet_ipcomp_attach(const void *unused __unused)
 637 {
 638
 639         /* XXX */
 640         V_ipcompstat.version = IPCOMPSTAT_VERSION;
 641 }
 642
 643 VNET_SYSINIT(vnet_ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
 644     vnet_ipcomp_attach, NULL);