xref: /netbsd-src/sys/netipsec/xform_ipcomp.c (revision 7c3f385475147b6e1c4753f2bee961630e2dfc40)
1 /*	$NetBSD: xform_ipcomp.c,v 1.17 2008/02/04 00:35:35 tls Exp $	*/
2 /*	$FreeBSD: src/sys/netipsec/xform_ipcomp.c,v 1.1.4.1 2003/01/24 05:11:36 sam 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 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: xform_ipcomp.c,v 1.17 2008/02/04 00:35:35 tls Exp $");
34 
35 /* IP payload compression protocol (IPComp), see RFC 2393 */
36 #include "opt_inet.h"
37 #ifdef __FreeBSD__
38 #include "opt_inet6.h"
39 #endif
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/mbuf.h>
44 #include <sys/socket.h>
45 #include <sys/kernel.h>
46 #include <sys/protosw.h>
47 #include <sys/sysctl.h>
48 
49 #include <netinet/in.h>
50 #include <netinet/in_systm.h>
51 #include <netinet/ip.h>
52 #include <netinet/ip_var.h>
53 
54 #include <net/route.h>
55 #include <netipsec/ipsec.h>
56 #include <netipsec/xform.h>
57 
58 #ifdef INET6
59 #include <netinet/ip6.h>
60 #include <netipsec/ipsec6.h>
61 #endif
62 
63 #include <netipsec/ipcomp.h>
64 #include <netipsec/ipcomp_var.h>
65 
66 #include <netipsec/key.h>
67 #include <netipsec/key_debug.h>
68 
69 #include <netipsec/ipsec_osdep.h>
70 
71 #include <opencrypto/cryptodev.h>
72 #include <opencrypto/deflate.h>
73 #include <opencrypto/xform.h>
74 
75 int	ipcomp_enable = 1;
76 struct	ipcompstat ipcompstat;
77 
78 #ifdef __FreeBSD__
79 SYSCTL_DECL(_net_inet_ipcomp);
80 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO,
81 	ipcomp_enable,	CTLFLAG_RW,	&ipcomp_enable,	0, "");
82 SYSCTL_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS,
83 	stats,		CTLFLAG_RD,	&ipcompstat,	ipcompstat, "");
84 #endif /* __FreeBSD__ */
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 	int ses;
110 
111 	/* NB: algorithm really comes in alg_enc and not alg_comp! */
112 	tcomp = ipcomp_algorithm_lookup(sav->alg_enc);
113 	if (tcomp == NULL) {
114 		DPRINTF(("ipcomp_init: unsupported compression algorithm %d\n",
115 			 sav->alg_comp));
116 		return EINVAL;
117 	}
118 	sav->alg_comp = sav->alg_enc;		/* set for doing histogram */
119 	sav->tdb_xform = xsp;
120 	sav->tdb_compalgxform = tcomp;
121 
122 	/* Initialize crypto session */
123 	bzero(&cric, sizeof (cric));
124 	cric.cri_alg = sav->tdb_compalgxform->type;
125 
126 	mutex_spin_enter(&crypto_mtx);
127 	ses = crypto_newsession(&sav->tdb_cryptoid, &cric, crypto_support);
128 	mutex_spin_exit(&crypto_mtx);
129 	return ses;
130 }
131 
132 /*
133  * ipcomp_zeroize() used when IPCA is deleted
134  */
135 static int
136 ipcomp_zeroize(struct secasvar *sav)
137 {
138 	int err;
139 
140 	mutex_spin_enter(&crypto_mtx);
141 	err = crypto_freesession(sav->tdb_cryptoid);
142 	mutex_spin_exit(&crypto_mtx);
143 	sav->tdb_cryptoid = 0;
144 	return err;
145 }
146 
147 /*
148  * ipcomp_input() gets called to uncompress an input packet
149  */
150 static int
151 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
152 {
153 	struct tdb_crypto *tc;
154 	struct cryptodesc *crdc;
155 	struct cryptop *crp;
156 	int hlen = IPCOMP_HLENGTH;
157 
158 	IPSEC_SPLASSERT_SOFTNET("ipcomp_input");
159 
160 	/* Get crypto descriptors */
161 	crp = crypto_getreq(1);
162 	if (crp == NULL) {
163 		m_freem(m);
164 		DPRINTF(("ipcomp_input: no crypto descriptors\n"));
165 		ipcompstat.ipcomps_crypto++;
166 		return ENOBUFS;
167 	}
168 	/* Get IPsec-specific opaque pointer */
169 	tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO);
170 	if (tc == NULL) {
171 		m_freem(m);
172 		crypto_freereq(crp);
173 		DPRINTF(("ipcomp_input: cannot allocate tdb_crypto\n"));
174 		ipcompstat.ipcomps_crypto++;
175 		return ENOBUFS;
176 	}
177 	crdc = crp->crp_desc;
178 
179 	crdc->crd_skip = skip + hlen;
180 	crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
181 	crdc->crd_inject = skip;
182 
183 	tc->tc_ptr = 0;
184 
185 	/* Decompression operation */
186 	crdc->crd_alg = sav->tdb_compalgxform->type;
187 
188 	/* Crypto operation descriptor */
189 	crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
190 	crp->crp_flags = CRYPTO_F_IMBUF;
191 	crp->crp_buf = m;
192 	crp->crp_callback = ipcomp_input_cb;
193 	crp->crp_sid = sav->tdb_cryptoid;
194 	crp->crp_opaque = tc;
195 
196 	/* These are passed as-is to the callback */
197 	tc->tc_spi = sav->spi;
198 	tc->tc_dst = sav->sah->saidx.dst;
199 	tc->tc_proto = sav->sah->saidx.proto;
200 	tc->tc_protoff = protoff;
201 	tc->tc_skip = skip;
202 
203 	return crypto_dispatch(crp);
204 }
205 
206 #ifdef INET6
207 #define	IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do {		     \
208 	if (saidx->dst.sa.sa_family == AF_INET6) {			     \
209 		error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \
210 	} else {							     \
211 		error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \
212 	}								     \
213 } while (0)
214 #else
215 #define	IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag)		     \
216 	(error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag))
217 #endif
218 
219 /*
220  * IPComp input callback from the crypto driver.
221  */
222 static int
223 ipcomp_input_cb(struct cryptop *crp)
224 {
225 	struct cryptodesc *crd;
226 	struct tdb_crypto *tc;
227 	int skip, protoff;
228 	struct mtag *mtag;
229 	struct mbuf *m;
230 	struct secasvar *sav;
231 	struct secasindex *saidx;
232 	int s, hlen = IPCOMP_HLENGTH, error, clen;
233 	u_int8_t nproto;
234 	void *addr;
235 	u_int16_t dport = 0;
236 	u_int16_t sport = 0;
237 #ifdef IPSEC_NAT_T
238 	struct m_tag * tag = NULL;
239 #endif
240 
241 	crd = crp->crp_desc;
242 
243 	tc = (struct tdb_crypto *) crp->crp_opaque;
244 	IPSEC_ASSERT(tc != NULL, ("ipcomp_input_cb: null opaque crypto data area!"));
245 	skip = tc->tc_skip;
246 	protoff = tc->tc_protoff;
247 	mtag = (struct mtag *) tc->tc_ptr;
248 	m = (struct mbuf *) crp->crp_buf;
249 
250 #ifdef IPSEC_NAT_T
251 	/* find the source port for NAT-T */
252 	if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) {
253 		sport = ((u_int16_t *)(tag + 1))[0];
254 		dport = ((u_int16_t *)(tag + 1))[1];
255 	}
256 #endif
257 
258 	s = splsoftnet();
259 
260 	sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi, sport, dport);
261 	if (sav == NULL) {
262 		ipcompstat.ipcomps_notdb++;
263 		DPRINTF(("ipcomp_input_cb: SA expired while in crypto\n"));
264 		error = ENOBUFS;		/*XXX*/
265 		goto bad;
266 	}
267 
268 	saidx = &sav->sah->saidx;
269 	IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
270 		saidx->dst.sa.sa_family == AF_INET6,
271 		("ah_input_cb: unexpected protocol family %u",
272 		 saidx->dst.sa.sa_family));
273 
274 	/* Check for crypto errors */
275 	if (crp->crp_etype) {
276 		/* Reset the session ID */
277 		if (sav->tdb_cryptoid != 0)
278 			sav->tdb_cryptoid = crp->crp_sid;
279 
280 		if (crp->crp_etype == EAGAIN) {
281 			KEY_FREESAV(&sav);
282 			splx(s);
283 			return crypto_dispatch(crp);
284 		}
285 
286 		ipcompstat.ipcomps_noxform++;
287 		DPRINTF(("ipcomp_input_cb: crypto error %d\n", crp->crp_etype));
288 		error = crp->crp_etype;
289 		goto bad;
290 	}
291 	/* Shouldn't happen... */
292 	if (m == NULL) {
293 		ipcompstat.ipcomps_crypto++;
294 		DPRINTF(("ipcomp_input_cb: null mbuf returned from crypto\n"));
295 		error = EINVAL;
296 		goto bad;
297 	}
298 	ipcompstat.ipcomps_hist[sav->alg_comp]++;
299 
300 	clen = crp->crp_olen;		/* Length of data after processing */
301 
302 	/* Release the crypto descriptors */
303 	free(tc, M_XDATA), tc = NULL;
304 	crypto_freereq(crp), crp = NULL;
305 
306 	/* In case it's not done already, adjust the size of the mbuf chain */
307 	m->m_pkthdr.len = clen + hlen + skip;
308 
309 	if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) {
310 		ipcompstat.ipcomps_hdrops++;		/*XXX*/
311 		DPRINTF(("ipcomp_input_cb: m_pullup failed\n"));
312 		error = EINVAL;				/*XXX*/
313 		goto bad;
314 	}
315 
316 	/* Keep the next protocol field */
317 	addr = (uint8_t*) mtod(m, struct ip *) + skip;
318 	nproto = ((struct ipcomp *) addr)->comp_nxt;
319 
320 	/* Remove the IPCOMP header */
321 	error = m_striphdr(m, skip, hlen);
322 	if (error) {
323 		ipcompstat.ipcomps_hdrops++;
324 		DPRINTF(("ipcomp_input_cb: bad mbuf chain, IPCA %s/%08lx\n",
325 			 ipsec_address(&sav->sah->saidx.dst),
326 			 (u_long) ntohl(sav->spi)));
327 		goto bad;
328 	}
329 
330 	/* Restore the Next Protocol field */
331 	m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
332 
333 	IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, NULL);
334 
335 	KEY_FREESAV(&sav);
336 	splx(s);
337 	return error;
338 bad:
339 	if (sav)
340 		KEY_FREESAV(&sav);
341 	splx(s);
342 	if (m)
343 		m_freem(m);
344 	if (tc != NULL)
345 		free(tc, M_XDATA);
346 	if (crp)
347 		crypto_freereq(crp);
348 	return error;
349 }
350 
351 /*
352  * IPComp output routine, called by ipsec[46]_process_packet()
353  */
354 static int
355 ipcomp_output(
356     struct mbuf *m,
357     struct ipsecrequest *isr,
358     struct mbuf **mp,
359     int skip,
360     int protoff
361 )
362 {
363 	struct secasvar *sav;
364 	struct comp_algo *ipcompx;
365 	int error, ralen, hlen, maxpacketsize;
366 	struct cryptodesc *crdc;
367 	struct cryptop *crp;
368 	struct tdb_crypto *tc;
369 
370 	IPSEC_SPLASSERT_SOFTNET("ipcomp_output");
371 	sav = isr->sav;
372 	IPSEC_ASSERT(sav != NULL, ("ipcomp_output: null SA"));
373 	ipcompx = sav->tdb_compalgxform;
374 	IPSEC_ASSERT(ipcompx != NULL, ("ipcomp_output: null compression xform"));
375 
376 	ralen = m->m_pkthdr.len - skip;	/* Raw payload length before comp. */
377 
378     /* Don't process the packet if it is too short */
379 	if (ralen < ipcompx->minlen) {
380 		ipcompstat.ipcomps_minlen++;
381 		return ipsec_process_done(m,isr);
382 	}
383 
384 	hlen = IPCOMP_HLENGTH;
385 
386 	ipcompstat.ipcomps_output++;
387 
388 	/* Check for maximum packet size violations. */
389 	switch (sav->sah->saidx.dst.sa.sa_family) {
390 #ifdef INET
391 	case AF_INET:
392 		maxpacketsize =  IP_MAXPACKET;
393 		break;
394 #endif /* INET */
395 #ifdef INET6
396 	case AF_INET6:
397 		maxpacketsize =  IPV6_MAXPACKET;
398 		break;
399 #endif /* INET6 */
400 	default:
401 		ipcompstat.ipcomps_nopf++;
402 		DPRINTF(("ipcomp_output: unknown/unsupported protocol family %d"
403 		    ", IPCA %s/%08lx\n",
404 		    sav->sah->saidx.dst.sa.sa_family,
405 		    ipsec_address(&sav->sah->saidx.dst),
406 		    (u_long) ntohl(sav->spi)));
407 		error = EPFNOSUPPORT;
408 		goto bad;
409 	}
410 	if (skip + hlen + ralen > maxpacketsize) {
411 		ipcompstat.ipcomps_toobig++;
412 		DPRINTF(("ipcomp_output: packet in IPCA %s/%08lx got too big "
413 		    "(len %u, max len %u)\n",
414 		    ipsec_address(&sav->sah->saidx.dst),
415 		    (u_long) ntohl(sav->spi),
416 		    skip + hlen + ralen, maxpacketsize));
417 		error = EMSGSIZE;
418 		goto bad;
419 	}
420 
421 	/* Update the counters */
422 	ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip;
423 
424 	m = m_clone(m);
425 	if (m == NULL) {
426 		ipcompstat.ipcomps_hdrops++;
427 		DPRINTF(("ipcomp_output: cannot clone mbuf chain, 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 
434 	/* Ok now, we can pass to the crypto processing */
435 
436 	/* Get crypto descriptors */
437 	crp = crypto_getreq(1);
438 	if (crp == NULL) {
439 		ipcompstat.ipcomps_crypto++;
440 		DPRINTF(("ipcomp_output: failed to acquire crypto descriptor\n"));
441 		error = ENOBUFS;
442 		goto bad;
443 	}
444 	crdc = crp->crp_desc;
445 
446 	/* Compression descriptor */
447 	crdc->crd_skip = skip;
448 	crdc->crd_len = m->m_pkthdr.len - skip;
449 	crdc->crd_flags = CRD_F_COMP;
450 	crdc->crd_inject = skip;
451 
452 	/* Compression operation */
453 	crdc->crd_alg = ipcompx->type;
454 
455 	/* IPsec-specific opaque crypto info */
456 	tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto),
457 		M_XDATA, M_NOWAIT|M_ZERO);
458 	if (tc == NULL) {
459 		ipcompstat.ipcomps_crypto++;
460 		DPRINTF(("ipcomp_output: failed to allocate tdb_crypto\n"));
461 		crypto_freereq(crp);
462 		error = ENOBUFS;
463 		goto bad;
464 	}
465 
466 	tc->tc_isr = isr;
467 	tc->tc_spi = sav->spi;
468 	tc->tc_dst = sav->sah->saidx.dst;
469 	tc->tc_proto = sav->sah->saidx.proto;
470 	tc->tc_skip = skip;
471 	tc->tc_protoff = protoff;
472 
473 	/* Crypto operation descriptor */
474 	crp->crp_ilen = m->m_pkthdr.len;	/* Total input length */
475 	crp->crp_flags = CRYPTO_F_IMBUF;
476 	crp->crp_buf = m;
477 	crp->crp_callback = ipcomp_output_cb;
478 	crp->crp_opaque = tc;
479 	crp->crp_sid = sav->tdb_cryptoid;
480 
481 	return crypto_dispatch(crp);
482 bad:
483 	if (m)
484 		m_freem(m);
485 	return (error);
486 }
487 
488 /*
489  * IPComp output callback from the crypto driver.
490  */
491 static int
492 ipcomp_output_cb(struct cryptop *crp)
493 {
494 	struct tdb_crypto *tc;
495 	struct ipsecrequest *isr;
496 	struct secasvar *sav;
497 	struct mbuf *m, *mo;
498 	int s, error, skip, rlen, roff;
499 	u_int8_t prot;
500 	u_int16_t cpi;
501 	struct ipcomp * ipcomp;
502 
503 
504 	tc = (struct tdb_crypto *) crp->crp_opaque;
505 	IPSEC_ASSERT(tc != NULL, ("ipcomp_output_cb: null opaque data area!"));
506 	m = (struct mbuf *) crp->crp_buf;
507 	skip = tc->tc_skip;
508 	rlen = crp->crp_ilen - skip;
509 
510 	s = splsoftnet();
511 
512 	isr = tc->tc_isr;
513 	sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi, 0, 0);
514 	if (sav == NULL) {
515 		ipcompstat.ipcomps_notdb++;
516 		DPRINTF(("ipcomp_output_cb: SA expired while in crypto\n"));
517 		error = ENOBUFS;		/*XXX*/
518 		goto bad;
519 	}
520 	IPSEC_ASSERT(isr->sav == sav, ("ipcomp_output_cb: SA changed\n"));
521 
522 	/* Check for crypto errors */
523 	if (crp->crp_etype) {
524 		/* Reset session ID */
525 		if (sav->tdb_cryptoid != 0)
526 			sav->tdb_cryptoid = crp->crp_sid;
527 
528 		if (crp->crp_etype == EAGAIN) {
529 			KEY_FREESAV(&sav);
530 			splx(s);
531 			return crypto_dispatch(crp);
532 		}
533 		ipcompstat.ipcomps_noxform++;
534 		DPRINTF(("ipcomp_output_cb: crypto error %d\n", crp->crp_etype));
535 		error = crp->crp_etype;
536 		goto bad;
537 	}
538 	/* Shouldn't happen... */
539 	if (m == NULL) {
540 		ipcompstat.ipcomps_crypto++;
541 		DPRINTF(("ipcomp_output_cb: bogus return buffer from crypto\n"));
542 		error = EINVAL;
543 		goto bad;
544 	}
545 	ipcompstat.ipcomps_hist[sav->alg_comp]++;
546 
547 	if (rlen > crp->crp_olen) {
548 		/* Inject IPCOMP header */
549 		mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
550 		if (mo == NULL) {
551 			ipcompstat.ipcomps_wrap++;
552 			DPRINTF(("ipcomp_output: failed to inject IPCOMP header for "
553 					 "IPCA %s/%08lx\n",
554 						ipsec_address(&sav->sah->saidx.dst),
555 						(u_long) ntohl(sav->spi)));
556 			error = ENOBUFS;
557 			goto bad;
558 		}
559 		ipcomp = (struct ipcomp *)(mtod(mo, char *) + roff);
560 
561 		/* Initialize the IPCOMP header */
562 		/* XXX alignment always correct? */
563 		switch (sav->sah->saidx.dst.sa.sa_family) {
564 #ifdef INET
565 		case AF_INET:
566 			ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
567 			 break;
568 #endif /* INET */
569 #ifdef INET6
570 		case AF_INET6:
571 			ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
572 		break;
573 #endif
574 		}
575 		ipcomp->comp_flags = 0;
576 
577 		if ((sav->flags & SADB_X_EXT_RAWCPI) == 0)
578 			 cpi = sav->alg_enc;
579 		else
580 			cpi = ntohl(sav->spi) & 0xffff;
581 		ipcomp->comp_cpi = htons(cpi);
582 
583 		/* Fix Next Protocol in IPv4/IPv6 header */
584 		prot = IPPROTO_IPCOMP;
585 		m_copyback(m, tc->tc_protoff, sizeof(u_int8_t), (u_char *)&prot);
586 
587 		/* Adjust the length in the IP header */
588 		switch (sav->sah->saidx.dst.sa.sa_family) {
589 #ifdef INET
590 		case AF_INET:
591 			mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
592 			break;
593 #endif /* INET */
594 #ifdef INET6
595 		case AF_INET6:
596 			mtod(m, struct ip6_hdr *)->ip6_plen =
597 				htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
598 			break;
599 #endif /* INET6 */
600 		default:
601 			ipcompstat.ipcomps_nopf++;
602 			DPRINTF(("ipcomp_output: unknown/unsupported protocol "
603 			    "family %d, IPCA %s/%08lx\n",
604 			    sav->sah->saidx.dst.sa.sa_family,
605 			    ipsec_address(&sav->sah->saidx.dst),
606 			    (u_long) ntohl(sav->spi)));
607 			error = EPFNOSUPPORT;
608 			goto bad;
609 		}
610 	} else {
611 		/* compression was useless, we have lost time */
612 		ipcompstat.ipcomps_uselesscomp++;
613 		DPRINTF(("ipcomp_output_cb: compression was useless : initial size was %d"
614 				   	"and compressed size is %d\n", rlen, crp->crp_olen));
615 	}
616 
617 
618 	/* Release the crypto descriptor */
619 	free(tc, M_XDATA);
620 	crypto_freereq(crp);
621 
622 	/* NB: m is reclaimed by ipsec_process_done. */
623 	error = ipsec_process_done(m, isr);
624 	KEY_FREESAV(&sav);
625 	splx(s);
626 	return error;
627 bad:
628 	if (sav)
629 		KEY_FREESAV(&sav);
630 	splx(s);
631 	if (m)
632 		m_freem(m);
633 	free(tc, M_XDATA);
634 	crypto_freereq(crp);
635 	return error;
636 }
637 
638 static struct xformsw ipcomp_xformsw = {
639 	XF_IPCOMP,		XFT_COMP,		"IPcomp",
640 	ipcomp_init,		ipcomp_zeroize,		ipcomp_input,
641 	ipcomp_output,
642 	NULL,
643 };
644 
645 INITFN void
646 ipcomp_attach(void)
647 {
648 	xform_register(&ipcomp_xformsw);
649 }
650 
651 #ifdef __FreeBSD__
652 SYSINIT(ipcomp_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, ipcomp_attach, NULL)
653 #endif /* __FreeBSD__ */
654