xref: /netbsd-src/sys/netipsec/xform_ipcomp.c (revision daf6c4152fcddc27c445489775ed1f66ab4ea9a9)
1 /*	$NetBSD: xform_ipcomp.c,v 1.22 2011/02/14 13:43:45 drochner 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 1.22 2011/02/14 13:43:45 drochner 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 #include <sys/socketvar.h> /* for softnet_lock */
49 
50 #include <netinet/in.h>
51 #include <netinet/in_systm.h>
52 #include <netinet/ip.h>
53 #include <netinet/ip_var.h>
54 
55 #include <net/route.h>
56 #include <netipsec/ipsec.h>
57 #include <netipsec/ipsec_private.h>
58 #include <netipsec/xform.h>
59 
60 #ifdef INET6
61 #include <netinet/ip6.h>
62 #include <netipsec/ipsec6.h>
63 #endif
64 
65 #include <netipsec/ipcomp.h>
66 #include <netipsec/ipcomp_var.h>
67 
68 #include <netipsec/key.h>
69 #include <netipsec/key_debug.h>
70 
71 #include <netipsec/ipsec_osdep.h>
72 
73 #include <opencrypto/cryptodev.h>
74 #include <opencrypto/deflate.h>
75 #include <opencrypto/xform.h>
76 
77 percpu_t *ipcompstat_percpu;
78 
79 int	ipcomp_enable = 1;
80 
81 #ifdef __FreeBSD__
82 SYSCTL_DECL(_net_inet_ipcomp);
83 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO,
84 	ipcomp_enable,	CTLFLAG_RW,	&ipcomp_enable,	0, "");
85 SYSCTL_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS,
86 	stats,		CTLFLAG_RD,	&ipcompstat,	ipcompstat, "");
87 #endif /* __FreeBSD__ */
88 
89 static int ipcomp_input_cb(struct cryptop *crp);
90 static int ipcomp_output_cb(struct cryptop *crp);
91 
92 struct comp_algo *
93 ipcomp_algorithm_lookup(int alg)
94 {
95 	if (alg >= IPCOMP_ALG_MAX)
96 		return NULL;
97 	switch (alg) {
98 	case SADB_X_CALG_DEFLATE:
99 		return &comp_algo_deflate;
100 	}
101 	return NULL;
102 }
103 
104 /*
105  * ipcomp_init() is called when an CPI is being set up.
106  */
107 static int
108 ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
109 {
110 	struct comp_algo *tcomp;
111 	struct cryptoini cric;
112 	int ses;
113 
114 	/* NB: algorithm really comes in alg_enc and not alg_comp! */
115 	tcomp = ipcomp_algorithm_lookup(sav->alg_enc);
116 	if (tcomp == NULL) {
117 		DPRINTF(("ipcomp_init: unsupported compression algorithm %d\n",
118 			 sav->alg_comp));
119 		return EINVAL;
120 	}
121 	sav->alg_comp = sav->alg_enc;		/* set for doing histogram */
122 	sav->tdb_xform = xsp;
123 	sav->tdb_compalgxform = tcomp;
124 
125 	/* Initialize crypto session */
126 	memset(&cric, 0, sizeof (cric));
127 	cric.cri_alg = sav->tdb_compalgxform->type;
128 
129 	mutex_spin_enter(&crypto_mtx);
130 	ses = crypto_newsession(&sav->tdb_cryptoid, &cric, crypto_support);
131 	mutex_spin_exit(&crypto_mtx);
132 	return ses;
133 }
134 
135 /*
136  * ipcomp_zeroize() used when IPCA is deleted
137  */
138 static int
139 ipcomp_zeroize(struct secasvar *sav)
140 {
141 	int err;
142 
143 	mutex_spin_enter(&crypto_mtx);
144 	err = crypto_freesession(sav->tdb_cryptoid);
145 	mutex_spin_exit(&crypto_mtx);
146 	sav->tdb_cryptoid = 0;
147 	return err;
148 }
149 
150 /*
151  * ipcomp_input() gets called to uncompress an input packet
152  */
153 static int
154 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
155 {
156 	struct tdb_crypto *tc;
157 	struct cryptodesc *crdc;
158 	struct cryptop *crp;
159 	int hlen = IPCOMP_HLENGTH;
160 
161 	IPSEC_SPLASSERT_SOFTNET("ipcomp_input");
162 
163 	/* Get crypto descriptors */
164 	crp = crypto_getreq(1);
165 	if (crp == NULL) {
166 		m_freem(m);
167 		DPRINTF(("ipcomp_input: no crypto descriptors\n"));
168 		IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
169 		return ENOBUFS;
170 	}
171 	/* Get IPsec-specific opaque pointer */
172 	tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO);
173 	if (tc == NULL) {
174 		m_freem(m);
175 		crypto_freereq(crp);
176 		DPRINTF(("ipcomp_input: cannot allocate tdb_crypto\n"));
177 		IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
178 		return ENOBUFS;
179 	}
180 	crdc = crp->crp_desc;
181 
182 	crdc->crd_skip = skip + hlen;
183 	crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
184 	crdc->crd_inject = skip;
185 
186 	tc->tc_ptr = 0;
187 
188 	/* Decompression operation */
189 	crdc->crd_alg = sav->tdb_compalgxform->type;
190 
191 	/* Crypto operation descriptor */
192 	crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
193 	crp->crp_flags = CRYPTO_F_IMBUF;
194 	crp->crp_buf = m;
195 	crp->crp_callback = ipcomp_input_cb;
196 	crp->crp_sid = sav->tdb_cryptoid;
197 	crp->crp_opaque = tc;
198 
199 	/* These are passed as-is to the callback */
200 	tc->tc_spi = sav->spi;
201 	tc->tc_dst = sav->sah->saidx.dst;
202 	tc->tc_proto = sav->sah->saidx.proto;
203 	tc->tc_protoff = protoff;
204 	tc->tc_skip = skip;
205 
206 	return crypto_dispatch(crp);
207 }
208 
209 #ifdef INET6
210 #define	IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do {		     \
211 	if (saidx->dst.sa.sa_family == AF_INET6) {			     \
212 		error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \
213 	} else {							     \
214 		error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \
215 	}								     \
216 } while (0)
217 #else
218 #define	IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag)		     \
219 	(error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag))
220 #endif
221 
222 /*
223  * IPComp input callback from the crypto driver.
224  */
225 static int
226 ipcomp_input_cb(struct cryptop *crp)
227 {
228 	struct cryptodesc *crd;
229 	struct tdb_crypto *tc;
230 	int skip, protoff;
231 	struct mtag *mtag;
232 	struct mbuf *m;
233 	struct secasvar *sav;
234 	struct secasindex *saidx;
235 	int s, hlen = IPCOMP_HLENGTH, error, clen;
236 	u_int8_t nproto;
237 	void *addr;
238 	u_int16_t dport = 0;
239 	u_int16_t sport = 0;
240 #ifdef IPSEC_NAT_T
241 	struct m_tag * tag = NULL;
242 #endif
243 
244 	crd = crp->crp_desc;
245 
246 	tc = (struct tdb_crypto *) crp->crp_opaque;
247 	IPSEC_ASSERT(tc != NULL, ("ipcomp_input_cb: null opaque crypto data area!"));
248 	skip = tc->tc_skip;
249 	protoff = tc->tc_protoff;
250 	mtag = (struct mtag *) tc->tc_ptr;
251 	m = (struct mbuf *) crp->crp_buf;
252 
253 #ifdef IPSEC_NAT_T
254 	/* find the source port for NAT-T */
255 	if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) {
256 		sport = ((u_int16_t *)(tag + 1))[0];
257 		dport = ((u_int16_t *)(tag + 1))[1];
258 	}
259 #endif
260 
261 	s = splsoftnet();
262 	mutex_enter(softnet_lock);
263 
264 	sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi, sport, dport);
265 	if (sav == NULL) {
266 		IPCOMP_STATINC(IPCOMP_STAT_NOTDB);
267 		DPRINTF(("ipcomp_input_cb: SA expired while in crypto\n"));
268 		error = ENOBUFS;		/*XXX*/
269 		goto bad;
270 	}
271 
272 	saidx = &sav->sah->saidx;
273 	IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
274 		saidx->dst.sa.sa_family == AF_INET6,
275 		("ah_input_cb: unexpected protocol family %u",
276 		 saidx->dst.sa.sa_family));
277 
278 	/* Check for crypto errors */
279 	if (crp->crp_etype) {
280 		/* Reset the session ID */
281 		if (sav->tdb_cryptoid != 0)
282 			sav->tdb_cryptoid = crp->crp_sid;
283 
284 		if (crp->crp_etype == EAGAIN) {
285 			KEY_FREESAV(&sav);
286 			mutex_exit(softnet_lock);
287 			splx(s);
288 			return crypto_dispatch(crp);
289 		}
290 
291 		IPCOMP_STATINC(IPCOMP_STAT_NOXFORM);
292 		DPRINTF(("ipcomp_input_cb: crypto error %d\n", crp->crp_etype));
293 		error = crp->crp_etype;
294 		goto bad;
295 	}
296 	/* Shouldn't happen... */
297 	if (m == NULL) {
298 		IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
299 		DPRINTF(("ipcomp_input_cb: null mbuf returned from crypto\n"));
300 		error = EINVAL;
301 		goto bad;
302 	}
303 	IPCOMP_STATINC(IPCOMP_STAT_HIST + sav->alg_comp);
304 
305 	/* Update the counters */
306 	IPCOMP_STATADD(IPCOMP_STAT_IBYTES, m->m_pkthdr.len - skip - hlen);
307 
308 
309 	clen = crp->crp_olen;		/* Length of data after processing */
310 
311 	/* Release the crypto descriptors */
312 	free(tc, M_XDATA), tc = NULL;
313 	crypto_freereq(crp), crp = NULL;
314 
315 	/* In case it's not done already, adjust the size of the mbuf chain */
316 	m->m_pkthdr.len = clen + hlen + skip;
317 
318 	if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) {
319 		IPCOMP_STATINC(IPCOMP_STAT_HDROPS);	/*XXX*/
320 		DPRINTF(("ipcomp_input_cb: m_pullup failed\n"));
321 		error = EINVAL;				/*XXX*/
322 		goto bad;
323 	}
324 
325 	/* Keep the next protocol field */
326 	addr = (uint8_t*) mtod(m, struct ip *) + skip;
327 	nproto = ((struct ipcomp *) addr)->comp_nxt;
328 
329 	/* Remove the IPCOMP header */
330 	error = m_striphdr(m, skip, hlen);
331 	if (error) {
332 		IPCOMP_STATINC(IPCOMP_STAT_HDROPS);
333 		DPRINTF(("ipcomp_input_cb: bad mbuf chain, IPCA %s/%08lx\n",
334 			 ipsec_address(&sav->sah->saidx.dst),
335 			 (u_long) ntohl(sav->spi)));
336 		goto bad;
337 	}
338 
339 	/* Restore the Next Protocol field */
340 	m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
341 
342 	IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, NULL);
343 
344 	KEY_FREESAV(&sav);
345 	mutex_exit(softnet_lock);
346 	splx(s);
347 	return error;
348 bad:
349 	if (sav)
350 		KEY_FREESAV(&sav);
351 	mutex_exit(softnet_lock);
352 	splx(s);
353 	if (m)
354 		m_freem(m);
355 	if (tc != NULL)
356 		free(tc, M_XDATA);
357 	if (crp)
358 		crypto_freereq(crp);
359 	return error;
360 }
361 
362 /*
363  * IPComp output routine, called by ipsec[46]_process_packet()
364  */
365 static int
366 ipcomp_output(
367     struct mbuf *m,
368     struct ipsecrequest *isr,
369     struct mbuf **mp,
370     int skip,
371     int protoff
372 )
373 {
374 	struct secasvar *sav;
375 	struct comp_algo *ipcompx;
376 	int error, ralen, hlen, maxpacketsize;
377 	struct cryptodesc *crdc;
378 	struct cryptop *crp;
379 	struct tdb_crypto *tc;
380 
381 	IPSEC_SPLASSERT_SOFTNET("ipcomp_output");
382 	sav = isr->sav;
383 	IPSEC_ASSERT(sav != NULL, ("ipcomp_output: null SA"));
384 	ipcompx = sav->tdb_compalgxform;
385 	IPSEC_ASSERT(ipcompx != NULL, ("ipcomp_output: null compression xform"));
386 
387 	ralen = m->m_pkthdr.len - skip;	/* Raw payload length before comp. */
388 
389     /* Don't process the packet if it is too short */
390 	if (ralen < ipcompx->minlen) {
391 		IPCOMP_STATINC(IPCOMP_STAT_MINLEN);
392 		return ipsec_process_done(m,isr);
393 	}
394 
395 	hlen = IPCOMP_HLENGTH;
396 
397 	IPCOMP_STATINC(IPCOMP_STAT_OUTPUT);
398 
399 	/* Check for maximum packet size violations. */
400 	switch (sav->sah->saidx.dst.sa.sa_family) {
401 #ifdef INET
402 	case AF_INET:
403 		maxpacketsize =  IP_MAXPACKET;
404 		break;
405 #endif /* INET */
406 #ifdef INET6
407 	case AF_INET6:
408 		maxpacketsize =  IPV6_MAXPACKET;
409 		break;
410 #endif /* INET6 */
411 	default:
412 		IPCOMP_STATINC(IPCOMP_STAT_NOPF);
413 		DPRINTF(("ipcomp_output: unknown/unsupported protocol family %d"
414 		    ", IPCA %s/%08lx\n",
415 		    sav->sah->saidx.dst.sa.sa_family,
416 		    ipsec_address(&sav->sah->saidx.dst),
417 		    (u_long) ntohl(sav->spi)));
418 		error = EPFNOSUPPORT;
419 		goto bad;
420 	}
421 	if (skip + hlen + ralen > maxpacketsize) {
422 		IPCOMP_STATINC(IPCOMP_STAT_TOOBIG);
423 		DPRINTF(("ipcomp_output: packet in IPCA %s/%08lx got too big "
424 		    "(len %u, max len %u)\n",
425 		    ipsec_address(&sav->sah->saidx.dst),
426 		    (u_long) ntohl(sav->spi),
427 		    skip + hlen + ralen, maxpacketsize));
428 		error = EMSGSIZE;
429 		goto bad;
430 	}
431 
432 	/* Update the counters */
433 	IPCOMP_STATADD(IPCOMP_STAT_OBYTES, m->m_pkthdr.len - skip);
434 
435 	m = m_clone(m);
436 	if (m == NULL) {
437 		IPCOMP_STATINC(IPCOMP_STAT_HDROPS);
438 		DPRINTF(("ipcomp_output: cannot clone mbuf chain, IPCA %s/%08lx\n",
439 		    ipsec_address(&sav->sah->saidx.dst),
440 		    (u_long) ntohl(sav->spi)));
441 		error = ENOBUFS;
442 		goto bad;
443 	}
444 
445 	/* Ok now, we can pass to the crypto processing */
446 
447 	/* Get crypto descriptors */
448 	crp = crypto_getreq(1);
449 	if (crp == NULL) {
450 		IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
451 		DPRINTF(("ipcomp_output: failed to acquire crypto descriptor\n"));
452 		error = ENOBUFS;
453 		goto bad;
454 	}
455 	crdc = crp->crp_desc;
456 
457 	/* Compression descriptor */
458 	crdc->crd_skip = skip;
459 	crdc->crd_len = m->m_pkthdr.len - skip;
460 	crdc->crd_flags = CRD_F_COMP;
461 	crdc->crd_inject = skip;
462 
463 	/* Compression operation */
464 	crdc->crd_alg = ipcompx->type;
465 
466 	/* IPsec-specific opaque crypto info */
467 	tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto),
468 		M_XDATA, M_NOWAIT|M_ZERO);
469 	if (tc == NULL) {
470 		IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
471 		DPRINTF(("ipcomp_output: failed to allocate tdb_crypto\n"));
472 		crypto_freereq(crp);
473 		error = ENOBUFS;
474 		goto bad;
475 	}
476 
477 	tc->tc_isr = isr;
478 	tc->tc_spi = sav->spi;
479 	tc->tc_dst = sav->sah->saidx.dst;
480 	tc->tc_proto = sav->sah->saidx.proto;
481 	tc->tc_skip = skip;
482 	tc->tc_protoff = protoff;
483 
484 	/* Crypto operation descriptor */
485 	crp->crp_ilen = m->m_pkthdr.len;	/* Total input length */
486 	crp->crp_flags = CRYPTO_F_IMBUF;
487 	crp->crp_buf = m;
488 	crp->crp_callback = ipcomp_output_cb;
489 	crp->crp_opaque = tc;
490 	crp->crp_sid = sav->tdb_cryptoid;
491 
492 	return crypto_dispatch(crp);
493 bad:
494 	if (m)
495 		m_freem(m);
496 	return (error);
497 }
498 
499 /*
500  * IPComp output callback from the crypto driver.
501  */
502 static int
503 ipcomp_output_cb(struct cryptop *crp)
504 {
505 	struct tdb_crypto *tc;
506 	struct ipsecrequest *isr;
507 	struct secasvar *sav;
508 	struct mbuf *m, *mo;
509 	int s, error, skip, rlen, roff;
510 	u_int8_t prot;
511 	u_int16_t cpi;
512 	struct ipcomp * ipcomp;
513 
514 
515 	tc = (struct tdb_crypto *) crp->crp_opaque;
516 	IPSEC_ASSERT(tc != NULL, ("ipcomp_output_cb: null opaque data area!"));
517 	m = (struct mbuf *) crp->crp_buf;
518 	skip = tc->tc_skip;
519 	rlen = crp->crp_ilen - skip;
520 
521 	s = splsoftnet();
522 	mutex_enter(softnet_lock);
523 
524 	isr = tc->tc_isr;
525 	sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi, 0, 0);
526 	if (sav == NULL) {
527 		IPCOMP_STATINC(IPCOMP_STAT_NOTDB);
528 		DPRINTF(("ipcomp_output_cb: SA expired while in crypto\n"));
529 		error = ENOBUFS;		/*XXX*/
530 		goto bad;
531 	}
532 	IPSEC_ASSERT(isr->sav == sav, ("ipcomp_output_cb: SA changed\n"));
533 
534 	/* Check for crypto errors */
535 	if (crp->crp_etype) {
536 		/* Reset session ID */
537 		if (sav->tdb_cryptoid != 0)
538 			sav->tdb_cryptoid = crp->crp_sid;
539 
540 		if (crp->crp_etype == EAGAIN) {
541 			KEY_FREESAV(&sav);
542 			mutex_exit(softnet_lock);
543 			splx(s);
544 			return crypto_dispatch(crp);
545 		}
546 		IPCOMP_STATINC(IPCOMP_STAT_NOXFORM);
547 		DPRINTF(("ipcomp_output_cb: crypto error %d\n", crp->crp_etype));
548 		error = crp->crp_etype;
549 		goto bad;
550 	}
551 	/* Shouldn't happen... */
552 	if (m == NULL) {
553 		IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
554 		DPRINTF(("ipcomp_output_cb: bogus return buffer from crypto\n"));
555 		error = EINVAL;
556 		goto bad;
557 	}
558 	IPCOMP_STATINC(IPCOMP_STAT_HIST + sav->alg_comp);
559 
560 	if (rlen > crp->crp_olen) {
561 		/* Inject IPCOMP header */
562 		mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
563 		if (mo == NULL) {
564 			IPCOMP_STATINC(IPCOMP_STAT_WRAP);
565 			DPRINTF(("ipcomp_output: failed to inject IPCOMP header for "
566 					 "IPCA %s/%08lx\n",
567 						ipsec_address(&sav->sah->saidx.dst),
568 						(u_long) ntohl(sav->spi)));
569 			error = ENOBUFS;
570 			goto bad;
571 		}
572 		ipcomp = (struct ipcomp *)(mtod(mo, char *) + roff);
573 
574 		/* Initialize the IPCOMP header */
575 		/* XXX alignment always correct? */
576 		switch (sav->sah->saidx.dst.sa.sa_family) {
577 #ifdef INET
578 		case AF_INET:
579 			ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
580 			 break;
581 #endif /* INET */
582 #ifdef INET6
583 		case AF_INET6:
584 			ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
585 		break;
586 #endif
587 		}
588 		ipcomp->comp_flags = 0;
589 
590 		if ((sav->flags & SADB_X_EXT_RAWCPI) == 0)
591 			 cpi = sav->alg_enc;
592 		else
593 			cpi = ntohl(sav->spi) & 0xffff;
594 		ipcomp->comp_cpi = htons(cpi);
595 
596 		/* Fix Next Protocol in IPv4/IPv6 header */
597 		prot = IPPROTO_IPCOMP;
598 		m_copyback(m, tc->tc_protoff, sizeof(u_int8_t), (u_char *)&prot);
599 
600 		/* Adjust the length in the IP header */
601 		switch (sav->sah->saidx.dst.sa.sa_family) {
602 #ifdef INET
603 		case AF_INET:
604 			mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
605 			break;
606 #endif /* INET */
607 #ifdef INET6
608 		case AF_INET6:
609 			mtod(m, struct ip6_hdr *)->ip6_plen =
610 				htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
611 			break;
612 #endif /* INET6 */
613 		default:
614 			IPCOMP_STATINC(IPCOMP_STAT_NOPF);
615 			DPRINTF(("ipcomp_output: unknown/unsupported protocol "
616 			    "family %d, IPCA %s/%08lx\n",
617 			    sav->sah->saidx.dst.sa.sa_family,
618 			    ipsec_address(&sav->sah->saidx.dst),
619 			    (u_long) ntohl(sav->spi)));
620 			error = EPFNOSUPPORT;
621 			goto bad;
622 		}
623 	} else {
624 		/* compression was useless, we have lost time */
625 		IPCOMP_STATINC(IPCOMP_STAT_USELESS);
626 		DPRINTF(("ipcomp_output_cb: compression was useless : initial size was %d"
627 				   	"and compressed size is %d\n", rlen, crp->crp_olen));
628 	}
629 
630 
631 	/* Release the crypto descriptor */
632 	free(tc, M_XDATA);
633 	crypto_freereq(crp);
634 
635 	/* NB: m is reclaimed by ipsec_process_done. */
636 	error = ipsec_process_done(m, isr);
637 	KEY_FREESAV(&sav);
638 	mutex_exit(softnet_lock);
639 	splx(s);
640 	return error;
641 bad:
642 	if (sav)
643 		KEY_FREESAV(&sav);
644 	mutex_exit(softnet_lock);
645 	splx(s);
646 	if (m)
647 		m_freem(m);
648 	free(tc, M_XDATA);
649 	crypto_freereq(crp);
650 	return error;
651 }
652 
653 static struct xformsw ipcomp_xformsw = {
654 	XF_IPCOMP,		XFT_COMP,		"IPcomp",
655 	ipcomp_init,		ipcomp_zeroize,		ipcomp_input,
656 	ipcomp_output,
657 	NULL,
658 };
659 
660 INITFN void
661 ipcomp_attach(void)
662 {
663 	ipcompstat_percpu = percpu_alloc(sizeof(uint64_t) * IPCOMP_NSTATS);
664 	xform_register(&ipcomp_xformsw);
665 }
666 
667 #ifdef __FreeBSD__
668 SYSINIT(ipcomp_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, ipcomp_attach, NULL)
669 #endif /* __FreeBSD__ */
670