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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/vnet.h>
52
53 #include <netipsec/ipsec.h>
54 #include <netipsec/xform.h>
55
56 #ifdef INET6
57 #include <netinet/ip6.h>
58 #include <netipsec/ipsec6.h>
59 #endif
60
61 #include <netipsec/ipcomp.h>
62 #include <netipsec/ipcomp_var.h>
63
64 #include <netipsec/key.h>
65 #include <netipsec/key_debug.h>
66
67 #include <opencrypto/cryptodev.h>
68 #include <opencrypto/deflate.h>
69 #include <opencrypto/xform.h>
70
71 VNET_DEFINE(int, ipcomp_enable) = 1;
72 VNET_PCPUSTAT_DEFINE(struct ipcompstat, ipcompstat);
73 VNET_PCPUSTAT_SYSINIT(ipcompstat);
74
75 #ifdef VIMAGE
76 VNET_PCPUSTAT_SYSUNINIT(ipcompstat);
77 #endif /* VIMAGE */
78
79 SYSCTL_DECL(_net_inet_ipcomp);
80 SYSCTL_VNET_INT(_net_inet_ipcomp, OID_AUTO,
81         ipcomp_enable,  CTLFLAG_RW,     &VNET_NAME(ipcomp_enable),      0, "");
82 SYSCTL_VNET_PCPUSTAT(_net_inet_ipcomp, IPSECCTL_STATS, stats,
83     struct ipcompstat, ipcompstat,
84     "IPCOMP statistics (struct ipcompstat, netipsec/ipcomp_var.h");
85
86 static int ipcomp_input_cb(struct cryptop *crp);
87 static int ipcomp_output_cb(struct cryptop *crp);
88
89 struct comp_algo *
90 ipcomp_algorithm_lookup(int alg)
91 {
92         if (alg >= IPCOMP_ALG_MAX)
93                 return NULL;
94         switch (alg) {
95         case SADB_X_CALG_DEFLATE:
96                 return &comp_algo_deflate;
97         }
98         return NULL;
99 }
100
101 /*
102  * ipcomp_init() is called when an CPI is being set up.
103  */
104 static int
105 ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
106 {
107         struct comp_algo *tcomp;
108         struct cryptoini cric;
109
110         /* NB: algorithm really comes in alg_enc and not alg_comp! */
111         tcomp = ipcomp_algorithm_lookup(sav->alg_enc);
112         if (tcomp == NULL) {
113                 DPRINTF(("%s: unsupported compression algorithm %d\n", __func__,
114                          sav->alg_comp));
115                 return EINVAL;
116         }
117         sav->alg_comp = sav->alg_enc;           /* set for doing histogram */
118         sav->tdb_xform = xsp;
119         sav->tdb_compalgxform = tcomp;
120
121         /* Initialize crypto session */
122         bzero(&cric, sizeof (cric));
123         cric.cri_alg = sav->tdb_compalgxform->type;
124
125         return crypto_newsession(&sav->tdb_cryptoid, &cric, V_crypto_support);
126 }
127
128 /*
129  * ipcomp_zeroize() used when IPCA is deleted
130  */
131 static int
132 ipcomp_zeroize(struct secasvar *sav)
133 {
134         int err;
135
136         err = crypto_freesession(sav->tdb_cryptoid);
137         sav->tdb_cryptoid = 0;
138         return err;
139 }
140
141 /*
142  * ipcomp_input() gets called to uncompress an input packet
143  */
144 static int
145 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
146 {
147         struct tdb_crypto *tc;
148         struct cryptodesc *crdc;
149         struct cryptop *crp;
150         struct ipcomp *ipcomp;
151         caddr_t addr;
152         int hlen = IPCOMP_HLENGTH;
153
154         /*
155          * Check that the next header of the IPComp is not IPComp again, before
156          * doing any real work.  Given it is not possible to do double
157          * compression it means someone is playing tricks on us.
158          */
159         if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
160                 IPCOMPSTAT_INC(ipcomps_hdrops);         /*XXX*/
161                 DPRINTF(("%s: m_pullup failed\n", __func__));
162                 return (ENOBUFS);
163         }
164         addr = (caddr_t) mtod(m, struct ip *) + skip;
165         ipcomp = (struct ipcomp *)addr;
166         if (ipcomp->comp_nxt == IPPROTO_IPCOMP) {
167                 m_freem(m);
168                 IPCOMPSTAT_INC(ipcomps_pdrops); /* XXX have our own stats? */
169                 DPRINTF(("%s: recursive compression detected\n", __func__));
170                 return (EINVAL);
171         }
172
173         /* Get crypto descriptors */
174         crp = crypto_getreq(1);
175         if (crp == NULL) {
176                 m_freem(m);
177                 DPRINTF(("%s: no crypto descriptors\n", __func__));
178                 IPCOMPSTAT_INC(ipcomps_crypto);
179                 return ENOBUFS;
180         }
181         /* Get IPsec-specific opaque pointer */
182         tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO);
183         if (tc == NULL) {
184                 m_freem(m);
185                 crypto_freereq(crp);
186                 DPRINTF(("%s: cannot allocate tdb_crypto\n", __func__));
187                 IPCOMPSTAT_INC(ipcomps_crypto);
188                 return ENOBUFS;
189         }
190         crdc = crp->crp_desc;
191
192         crdc->crd_skip = skip + hlen;
193         crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
194         crdc->crd_inject = skip;
195
196         tc->tc_ptr = 0;
197
198         /* Decompression operation */
199         crdc->crd_alg = sav->tdb_compalgxform->type;
200
201         /* Crypto operation descriptor */
202         crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
203         crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
204         crp->crp_buf = (caddr_t) m;
205         crp->crp_callback = ipcomp_input_cb;
206         crp->crp_sid = sav->tdb_cryptoid;
207         crp->crp_opaque = (caddr_t) tc;
208
209         /* These are passed as-is to the callback */
210         tc->tc_spi = sav->spi;
211         tc->tc_dst = sav->sah->saidx.dst;
212         tc->tc_proto = sav->sah->saidx.proto;
213         tc->tc_protoff = protoff;
214         tc->tc_skip = skip;
215         KEY_ADDREFSA(sav);
216         tc->tc_sav = sav;
217
218         return crypto_dispatch(crp);
219 }
220
221 /*
222  * IPComp input callback from the crypto driver.
223  */
224 static int
225 ipcomp_input_cb(struct cryptop *crp)
226 {
227         struct cryptodesc *crd;
228         struct tdb_crypto *tc;
229         int skip, protoff;
230         struct mtag *mtag;
231         struct mbuf *m;
232         struct secasvar *sav;
233         struct secasindex *saidx;
234         int hlen = IPCOMP_HLENGTH, error, clen;
235         u_int8_t nproto;
236         caddr_t addr;
237
238         crd = crp->crp_desc;
239
240         tc = (struct tdb_crypto *) crp->crp_opaque;
241         IPSEC_ASSERT(tc != NULL, ("null opaque crypto data area!"));
242         skip = tc->tc_skip;
243         protoff = tc->tc_protoff;
244         mtag = (struct mtag *) tc->tc_ptr;
245         m = (struct mbuf *) crp->crp_buf;
246
247         sav = tc->tc_sav;
248         IPSEC_ASSERT(sav != NULL, ("null SA!"));
249
250         saidx = &sav->sah->saidx;
251         IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
252                 saidx->dst.sa.sa_family == AF_INET6,
253                 ("unexpected protocol family %u", saidx->dst.sa.sa_family));
254
255         /* Check for crypto errors */
256         if (crp->crp_etype) {
257                 /* Reset the session ID */
258                 if (sav->tdb_cryptoid != 0)
259                         sav->tdb_cryptoid = crp->crp_sid;
260
261                 if (crp->crp_etype == EAGAIN) {
262                         return crypto_dispatch(crp);
263                 }
264                 IPCOMPSTAT_INC(ipcomps_noxform);
265                 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
266                 error = crp->crp_etype;
267                 goto bad;
268         }
269         /* Shouldn't happen... */
270         if (m == NULL) {
271                 IPCOMPSTAT_INC(ipcomps_crypto);
272                 DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
273                 error = EINVAL;
274                 goto bad;
275         }
276         IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
277
278         clen = crp->crp_olen;           /* Length of data after processing */
279
280         /* Release the crypto descriptors */
281         free(tc, M_XDATA), tc = NULL;
282         crypto_freereq(crp), crp = NULL;
283
284         /* In case it's not done already, adjust the size of the mbuf chain */
285         m->m_pkthdr.len = clen + hlen + skip;
286
287         if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) {
288                 IPCOMPSTAT_INC(ipcomps_hdrops);         /*XXX*/
289                 DPRINTF(("%s: m_pullup failed\n", __func__));
290                 error = EINVAL;                         /*XXX*/
291                 goto bad;
292         }
293
294         /* Keep the next protocol field */
295         addr = (caddr_t) mtod(m, struct ip *) + skip;
296         nproto = ((struct ipcomp *) addr)->comp_nxt;
297
298         /* Remove the IPCOMP header */
299         error = m_striphdr(m, skip, hlen);
300         if (error) {
301                 IPCOMPSTAT_INC(ipcomps_hdrops);
302                 DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__,
303                          ipsec_address(&sav->sah->saidx.dst),
304                          (u_long) ntohl(sav->spi)));
305                 goto bad;
306         }
307
308         /* Restore the Next Protocol field */
309         m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
310
311         switch (saidx->dst.sa.sa_family) {
312 #ifdef INET6
313         case AF_INET6:
314                 error = ipsec6_common_input_cb(m, sav, skip, protoff, NULL);
315                 break;
316 #endif
317 #ifdef INET
318         case AF_INET:
319                 error = ipsec4_common_input_cb(m, sav, skip, protoff, NULL);
320                 break;
321 #endif
322         default:
323                 panic("%s: Unexpected address family: %d saidx=%p", __func__,
324                     saidx->dst.sa.sa_family, saidx);
325         }
326
327         KEY_FREESAV(&sav);
328         return error;
329 bad:
330         if (sav)
331                 KEY_FREESAV(&sav);
332         if (m)
333                 m_freem(m);
334         if (tc != NULL)
335                 free(tc, M_XDATA);
336         if (crp)
337                 crypto_freereq(crp);
338         return error;
339 }
340
341 /*
342  * IPComp output routine, called by ipsec[46]_process_packet()
343  */
344 static int
345 ipcomp_output(
346         struct mbuf *m,
347         struct ipsecrequest *isr,
348         struct mbuf **mp,
349         int skip,
350         int protoff
351 )
352 {
353         struct secasvar *sav;
354         struct comp_algo *ipcompx;
355         int error, ralen, maxpacketsize;
356         struct cryptodesc *crdc;
357         struct cryptop *crp;
358         struct tdb_crypto *tc;
359
360         sav = isr->sav;
361         IPSEC_ASSERT(sav != NULL, ("null SA"));
362         ipcompx = sav->tdb_compalgxform;
363         IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
364
365         /*
366          * Do not touch the packet in case our payload to compress
367          * is lower than the minimal threshold of the compression
368          * alogrithm.  We will just send out the data uncompressed.
369          * See RFC 3173, 2.2. Non-Expansion Policy.
370          */
371         if (m->m_pkthdr.len <= ipcompx->minlen) {
372                 IPCOMPSTAT_INC(ipcomps_threshold);
373                 return ipsec_process_done(m, isr);
374         }
375
376         ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
377         IPCOMPSTAT_INC(ipcomps_output);
378
379         /* Check for maximum packet size violations. */
380         switch (sav->sah->saidx.dst.sa.sa_family) {
381 #ifdef INET
382         case AF_INET:
383                 maxpacketsize = IP_MAXPACKET;
384                 break;
385 #endif /* INET */
386 #ifdef INET6
387         case AF_INET6:
388                 maxpacketsize = IPV6_MAXPACKET;
389                 break;
390 #endif /* INET6 */
391         default:
392                 IPCOMPSTAT_INC(ipcomps_nopf);
393                 DPRINTF(("%s: unknown/unsupported protocol family %d, "
394                     "IPCA %s/%08lx\n", __func__,
395                     sav->sah->saidx.dst.sa.sa_family,
396                     ipsec_address(&sav->sah->saidx.dst),
397                     (u_long) ntohl(sav->spi)));
398                 error = EPFNOSUPPORT;
399                 goto bad;
400         }
401         if (ralen + skip + IPCOMP_HLENGTH > maxpacketsize) {
402                 IPCOMPSTAT_INC(ipcomps_toobig);
403                 DPRINTF(("%s: packet in IPCA %s/%08lx got too big "
404                     "(len %u, max len %u)\n", __func__,
405                     ipsec_address(&sav->sah->saidx.dst),
406                     (u_long) ntohl(sav->spi),
407                     ralen + skip + IPCOMP_HLENGTH, maxpacketsize));
408                 error = EMSGSIZE;
409                 goto bad;
410         }
411
412         /* Update the counters */
413         IPCOMPSTAT_ADD(ipcomps_obytes, m->m_pkthdr.len - skip);
414
415         m = m_unshare(m, M_NOWAIT);
416         if (m == NULL) {
417                 IPCOMPSTAT_INC(ipcomps_hdrops);
418                 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
419                     __func__, ipsec_address(&sav->sah->saidx.dst),
420                     (u_long) ntohl(sav->spi)));
421                 error = ENOBUFS;
422                 goto bad;
423         }
424
425         /* Ok now, we can pass to the crypto processing. */
426
427         /* Get crypto descriptors */
428         crp = crypto_getreq(1);
429         if (crp == NULL) {
430                 IPCOMPSTAT_INC(ipcomps_crypto);
431                 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
432                 error = ENOBUFS;
433                 goto bad;
434         }
435         crdc = crp->crp_desc;
436
437         /* Compression descriptor */
438         crdc->crd_skip = skip;
439         crdc->crd_len = ralen;
440         crdc->crd_flags = CRD_F_COMP;
441         crdc->crd_inject = skip;
442
443         /* Compression operation */
444         crdc->crd_alg = ipcompx->type;
445
446         /* IPsec-specific opaque crypto info */
447         tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto),
448                 M_XDATA, M_NOWAIT|M_ZERO);
449         if (tc == NULL) {
450                 IPCOMPSTAT_INC(ipcomps_crypto);
451                 DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__));
452                 crypto_freereq(crp);
453                 error = ENOBUFS;
454                 goto bad;
455         }
456
457         tc->tc_isr = isr;
458         KEY_ADDREFSA(sav);
459         tc->tc_sav = sav;
460         tc->tc_spi = sav->spi;
461         tc->tc_dst = sav->sah->saidx.dst;
462         tc->tc_proto = sav->sah->saidx.proto;
463         tc->tc_protoff = protoff;
464         tc->tc_skip = skip;
465
466         /* Crypto operation descriptor */
467         crp->crp_ilen = m->m_pkthdr.len;        /* Total input length */
468         crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
469         crp->crp_buf = (caddr_t) m;
470         crp->crp_callback = ipcomp_output_cb;
471         crp->crp_opaque = (caddr_t) tc;
472         crp->crp_sid = sav->tdb_cryptoid;
473
474         return crypto_dispatch(crp);
475 bad:
476         if (m)
477                 m_freem(m);
478         return (error);
479 }
480
481 /*
482  * IPComp output callback from the crypto driver.
483  */
484 static int
485 ipcomp_output_cb(struct cryptop *crp)
486 {
487         struct tdb_crypto *tc;
488         struct ipsecrequest *isr;
489         struct secasvar *sav;
490         struct mbuf *m;
491         int error, skip;
492
493         tc = (struct tdb_crypto *) crp->crp_opaque;
494         IPSEC_ASSERT(tc != NULL, ("null opaque data area!"));
495         m = (struct mbuf *) crp->crp_buf;
496         skip = tc->tc_skip;
497
498         isr = tc->tc_isr;
499         IPSECREQUEST_LOCK(isr);
500         sav = tc->tc_sav;
501         /* With the isr lock released SA pointer can be updated. */
502         if (sav != isr->sav) {
503                 IPCOMPSTAT_INC(ipcomps_notdb);
504                 DPRINTF(("%s: SA expired while in crypto\n", __func__));
505                 error = ENOBUFS;                /*XXX*/
506                 goto bad;
507         }
508
509         /* Check for crypto errors */
510         if (crp->crp_etype) {
511                 /* Reset the session ID */
512                 if (sav->tdb_cryptoid != 0)
513                         sav->tdb_cryptoid = crp->crp_sid;
514
515                 if (crp->crp_etype == EAGAIN) {
516                         IPSECREQUEST_UNLOCK(isr);
517                         return crypto_dispatch(crp);
518                 }
519                 IPCOMPSTAT_INC(ipcomps_noxform);
520                 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
521                 error = crp->crp_etype;
522                 goto bad;
523         }
524         /* Shouldn't happen... */
525         if (m == NULL) {
526                 IPCOMPSTAT_INC(ipcomps_crypto);
527                 DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
528                 error = EINVAL;
529                 goto bad;
530         }
531         IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
532
533         if (crp->crp_ilen - skip > crp->crp_olen) {
534                 struct mbuf *mo;
535                 struct ipcomp *ipcomp;
536                 int roff;
537                 uint8_t prot;
538
539                 /* Compression helped, inject IPCOMP header. */
540                 mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
541                 if (mo == NULL) {
542                         IPCOMPSTAT_INC(ipcomps_wrap);
543                         DPRINTF(("%s: IPCOMP header inject failed for IPCA %s/%08lx\n",
544                             __func__, ipsec_address(&sav->sah->saidx.dst),
545                             (u_long) ntohl(sav->spi)));
546                         error = ENOBUFS;
547                         goto bad;
548                 }
549                 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
550
551                 /* Initialize the IPCOMP header */
552                 /* XXX alignment always correct? */
553                 switch (sav->sah->saidx.dst.sa.sa_family) {
554 #ifdef INET
555                 case AF_INET:
556                         ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
557                         break;
558 #endif /* INET */
559 #ifdef INET6
560                 case AF_INET6:
561                         ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
562                         break;
563 #endif
564                 }
565                 ipcomp->comp_flags = 0;
566                 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
567
568                 /* Fix Next Protocol in IPv4/IPv6 header */
569                 prot = IPPROTO_IPCOMP;
570                 m_copyback(m, tc->tc_protoff, sizeof(u_int8_t),
571                     (u_char *)&prot);
572
573                 /* Adjust the length in the IP header */
574                 switch (sav->sah->saidx.dst.sa.sa_family) {
575 #ifdef INET
576                 case AF_INET:
577                         mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
578                         break;
579 #endif /* INET */
580 #ifdef INET6
581                 case AF_INET6:
582                         mtod(m, struct ip6_hdr *)->ip6_plen =
583                                 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
584                         break;
585 #endif /* INET6 */
586                 default:
587                         IPCOMPSTAT_INC(ipcomps_nopf);
588                         DPRINTF(("%s: unknown/unsupported protocol "
589                             "family %d, IPCA %s/%08lx\n", __func__,
590                             sav->sah->saidx.dst.sa.sa_family,
591                             ipsec_address(&sav->sah->saidx.dst),
592                             (u_long) ntohl(sav->spi)));
593                         error = EPFNOSUPPORT;
594                         goto bad;
595                 }
596         } else {
597                 /* Compression was useless, we have lost time. */
598                 IPCOMPSTAT_INC(ipcomps_uncompr);
599                 DPRINTF(("%s: compressions was useless %d - %d <= %d\n",
600                     __func__, crp->crp_ilen, skip, crp->crp_olen));
601                 /* XXX remember state to not compress the next couple
602                  *     of packets, RFC 3173, 2.2. Non-Expansion Policy */
603         }
604
605         /* Release the crypto descriptor */
606         free(tc, M_XDATA);
607         crypto_freereq(crp);
608
609         /* NB: m is reclaimed by ipsec_process_done. */
610         error = ipsec_process_done(m, isr);
611         KEY_FREESAV(&sav);
612         IPSECREQUEST_UNLOCK(isr);
613         return error;
614 bad:
615         if (sav)
616                 KEY_FREESAV(&sav);
617         IPSECREQUEST_UNLOCK(isr);
618         if (m)
619                 m_freem(m);
620         free(tc, M_XDATA);
621         crypto_freereq(crp);
622         return error;
623 }
624
625 static struct xformsw ipcomp_xformsw = {
626         XF_IPCOMP,              XFT_COMP,               "IPcomp",
627         ipcomp_init,            ipcomp_zeroize,         ipcomp_input,
628         ipcomp_output
629 };
630
631 static void
632 ipcomp_attach(void)
633 {
634
635         xform_register(&ipcomp_xformsw);
636 }
637
638 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipcomp_attach, NULL);