1/* $OpenBSD: ip_ipcomp.c,v 1.1 2001/07/05 12:08:52 jjbg Exp $ */
2
3/*-
4 * SPDX-License-Identifier: BSD-3-Clause
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#include "opt_ipsec.h"
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/malloc.h>
40#include <sys/mbuf.h>
41#include <sys/lock.h>
42#include <sys/mutex.h>
43#include <sys/socket.h>
44#include <sys/kernel.h>
45#include <sys/protosw.h>
46#include <sys/sysctl.h>
47
48#include <netinet/in.h>
49#include <netinet/in_systm.h>
50#include <netinet/ip.h>
51#include <netinet/ip_var.h>
52#include <netinet/ip_encap.h>
53
54#include <net/netisr.h>
55#include <net/vnet.h>
56#include <net/if.h>	/* XXXGL: net_epoch should move out there */
57#include <net/if_var.h>	/* XXXGL: net_epoch should move out there */
58
59#include <netipsec/ipsec.h>
60#include <netipsec/xform.h>
61
62#ifdef INET6
63#include <netinet/ip6.h>
64#include <netinet6/ip6_var.h>
65#include <netipsec/ipsec6.h>
66#endif
67
68#include <netipsec/ipcomp.h>
69#include <netipsec/ipcomp_var.h>
70
71#include <netipsec/key.h>
72#include <netipsec/key_debug.h>
73
74#include <opencrypto/cryptodev.h>
75#include <opencrypto/deflate.h>
76#include <opencrypto/xform.h>
77
78VNET_DEFINE(int, ipcomp_enable) = 1;
79VNET_PCPUSTAT_DEFINE(struct ipcompstat, ipcompstat);
80VNET_PCPUSTAT_SYSINIT(ipcompstat);
81
82#ifdef VIMAGE
83VNET_PCPUSTAT_SYSUNINIT(ipcompstat);
84#endif /* VIMAGE */
85
86SYSCTL_DECL(_net_inet_ipcomp);
87SYSCTL_INT(_net_inet_ipcomp, OID_AUTO, ipcomp_enable,
88	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipcomp_enable), 0, "");
89SYSCTL_VNET_PCPUSTAT(_net_inet_ipcomp, IPSECCTL_STATS, stats,
90    struct ipcompstat, ipcompstat,
91    "IPCOMP statistics (struct ipcompstat, netipsec/ipcomp_var.h");
92
93static MALLOC_DEFINE(M_IPCOMP, "ipcomp", "IPCOMP");
94
95static int ipcomp_input_cb(struct cryptop *crp);
96static int ipcomp_output_cb(struct cryptop *crp);
97
98/*
99 * RFC 3173 p 2.2. Non-Expansion Policy:
100 * If the total size of a compressed payload and the IPComp header, as
101 * defined in section 3, is not smaller than the size of the original
102 * payload, the IP datagram MUST be sent in the original non-compressed
103 * form.
104 *
105 * When we use IPComp in tunnel mode, for small packets we will receive
106 * encapsulated IP-IP datagrams without any compression and without IPComp
107 * header.
108 */
109static int
110ipcomp_encapcheck(union sockaddr_union *src, union sockaddr_union *dst)
111{
112	struct secasvar *sav;
113
114	sav = key_allocsa_tunnel(src, dst, IPPROTO_IPCOMP);
115	if (sav == NULL)
116		return (0);
117	key_freesav(&sav);
118
119	if (src->sa.sa_family == AF_INET)
120		return (sizeof(struct in_addr) << 4);
121	else
122		return (sizeof(struct in6_addr) << 4);
123}
124
125static int
126ipcomp_nonexp_input(struct mbuf *m, int off, int proto, void *arg __unused)
127{
128	int isr;
129
130	NET_EPOCH_ASSERT();
131
132	switch (proto) {
133#ifdef INET
134	case IPPROTO_IPV4:
135		isr = NETISR_IP;
136		break;
137#endif
138#ifdef INET6
139	case IPPROTO_IPV6:
140		isr = NETISR_IPV6;
141		break;
142#endif
143	default:
144		IPCOMPSTAT_INC(ipcomps_nopf);
145		m_freem(m);
146		return (IPPROTO_DONE);
147	}
148	m_adj(m, off);
149	IPCOMPSTAT_ADD(ipcomps_ibytes, m->m_pkthdr.len);
150	IPCOMPSTAT_INC(ipcomps_input);
151	netisr_dispatch(isr, m);
152	return (IPPROTO_DONE);
153}
154
155/*
156 * ipcomp_init() is called when an CPI is being set up.
157 */
158static int
159ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
160{
161	const struct comp_algo *tcomp;
162	struct crypto_session_params csp;
163
164	/* NB: algorithm really comes in alg_enc and not alg_comp! */
165	tcomp = comp_algorithm_lookup(sav->alg_enc);
166	if (tcomp == NULL) {
167		DPRINTF(("%s: unsupported compression algorithm %d\n", __func__,
168			 sav->alg_comp));
169		return EINVAL;
170	}
171	sav->alg_comp = sav->alg_enc;		/* set for doing histogram */
172	sav->tdb_xform = xsp;
173	sav->tdb_compalgxform = tcomp;
174
175	/* Initialize crypto session */
176	memset(&csp, 0, sizeof(csp));
177	csp.csp_mode = CSP_MODE_COMPRESS;
178	csp.csp_cipher_alg = sav->tdb_compalgxform->type;
179
180	return crypto_newsession(&sav->tdb_cryptoid, &csp, V_crypto_support);
181}
182
183/*
184 * ipcomp_cleanup() used when IPCA is deleted
185 */
186static void
187ipcomp_cleanup(struct secasvar *sav)
188{
189
190	crypto_freesession(sav->tdb_cryptoid);
191	sav->tdb_cryptoid = NULL;
192}
193
194/*
195 * ipcomp_input() gets called to uncompress an input packet
196 */
197static int
198ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
199{
200	struct xform_data *xd;
201	struct cryptop *crp;
202	struct ipcomp *ipcomp;
203	crypto_session_t cryptoid;
204	caddr_t addr;
205	int error, hlen = IPCOMP_HLENGTH;
206
207	SECASVAR_RLOCK_TRACKER;
208
209	/*
210	 * Check that the next header of the IPComp is not IPComp again, before
211	 * doing any real work.  Given it is not possible to do double
212	 * compression it means someone is playing tricks on us.
213	 */
214	error = ENOBUFS;
215	if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
216		IPCOMPSTAT_INC(ipcomps_hdrops);		/*XXX*/
217		DPRINTF(("%s: m_pullup failed\n", __func__));
218		key_freesav(&sav);
219		return (error);
220	}
221	addr = (caddr_t) mtod(m, struct ip *) + skip;
222	ipcomp = (struct ipcomp *)addr;
223	if (ipcomp->comp_nxt == IPPROTO_IPCOMP) {
224		IPCOMPSTAT_INC(ipcomps_pdrops);	/* XXX have our own stats? */
225		DPRINTF(("%s: recursive compression detected\n", __func__));
226		error = EINVAL;
227		goto bad;
228	}
229
230	SECASVAR_RLOCK(sav);
231	cryptoid = sav->tdb_cryptoid;
232	SECASVAR_RUNLOCK(sav);
233
234	/* Get crypto descriptors */
235	crp = crypto_getreq(cryptoid, M_NOWAIT);
236	if (crp == NULL) {
237		DPRINTF(("%s: no crypto descriptors\n", __func__));
238		IPCOMPSTAT_INC(ipcomps_crypto);
239		goto bad;
240	}
241	/* Get IPsec-specific opaque pointer */
242	xd = malloc(sizeof(*xd), M_IPCOMP, M_NOWAIT | M_ZERO);
243	if (xd == NULL) {
244		DPRINTF(("%s: cannot allocate xform_data\n", __func__));
245		IPCOMPSTAT_INC(ipcomps_crypto);
246		crypto_freereq(crp);
247		goto bad;
248	}
249
250	/* Decompression operation */
251	crp->crp_op = CRYPTO_OP_DECOMPRESS;
252	crp->crp_payload_start = skip + hlen;
253	crp->crp_payload_length = m->m_pkthdr.len - (skip + hlen);
254
255	/* Crypto operation descriptor */
256	crp->crp_flags = CRYPTO_F_CBIFSYNC;
257	crypto_use_mbuf(crp, m);
258	crp->crp_callback = ipcomp_input_cb;
259	crp->crp_opaque = xd;
260
261	/* These are passed as-is to the callback */
262	xd->sav = sav;
263	xd->protoff = protoff;
264	xd->skip = skip;
265	xd->vnet = curvnet;
266	xd->cryptoid = cryptoid;
267
268	SECASVAR_RLOCK(sav);
269	crp->crp_session = xd->cryptoid = sav->tdb_cryptoid;
270	SECASVAR_RUNLOCK(sav);
271
272	return crypto_dispatch(crp);
273bad:
274	m_freem(m);
275	key_freesav(&sav);
276	return (error);
277}
278
279/*
280 * IPComp input callback from the crypto driver.
281 */
282static int
283ipcomp_input_cb(struct cryptop *crp)
284{
285	IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
286	struct xform_data *xd;
287	struct mbuf *m;
288	struct secasvar *sav;
289	struct secasindex *saidx;
290	caddr_t addr;
291	crypto_session_t cryptoid;
292	int hlen = IPCOMP_HLENGTH, error, clen;
293	int skip, protoff;
294	uint8_t nproto;
295
296	m = crp->crp_buf.cb_mbuf;
297	xd = crp->crp_opaque;
298	CURVNET_SET(xd->vnet);
299	sav = xd->sav;
300	skip = xd->skip;
301	protoff = xd->protoff;
302	cryptoid = xd->cryptoid;
303	saidx = &sav->sah->saidx;
304	IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
305		saidx->dst.sa.sa_family == AF_INET6,
306		("unexpected protocol family %u", saidx->dst.sa.sa_family));
307
308	/* Check for crypto errors */
309	if (crp->crp_etype) {
310		if (crp->crp_etype == EAGAIN) {
311			/* Reset the session ID */
312			if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
313				crypto_freesession(cryptoid);
314			xd->cryptoid = crp->crp_session;
315			CURVNET_RESTORE();
316			return (crypto_dispatch(crp));
317		}
318		IPCOMPSTAT_INC(ipcomps_noxform);
319		DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
320		error = crp->crp_etype;
321		goto bad;
322	}
323	/* Shouldn't happen... */
324	if (m == NULL) {
325		IPCOMPSTAT_INC(ipcomps_crypto);
326		DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
327		error = EINVAL;
328		goto bad;
329	}
330	IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
331
332	clen = crp->crp_olen;		/* Length of data after processing */
333
334	/* Release the crypto descriptors */
335	free(xd, M_IPCOMP), xd = NULL;
336	crypto_freereq(crp), crp = NULL;
337
338	/* In case it's not done already, adjust the size of the mbuf chain */
339	m->m_pkthdr.len = clen + hlen + skip;
340
341	if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
342		IPCOMPSTAT_INC(ipcomps_hdrops);		/*XXX*/
343		DPRINTF(("%s: m_pullup failed\n", __func__));
344		error = EINVAL;				/*XXX*/
345		goto bad;
346	}
347
348	/* Keep the next protocol field */
349	addr = (caddr_t) mtod(m, struct ip *) + skip;
350	nproto = ((struct ipcomp *) addr)->comp_nxt;
351
352	/* Remove the IPCOMP header */
353	error = m_striphdr(m, skip, hlen);
354	if (error) {
355		IPCOMPSTAT_INC(ipcomps_hdrops);
356		DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__,
357		    ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
358		    (u_long) ntohl(sav->spi)));
359		goto bad;
360	}
361
362	/* Restore the Next Protocol field */
363	m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
364
365	switch (saidx->dst.sa.sa_family) {
366#ifdef INET6
367	case AF_INET6:
368		error = ipsec6_common_input_cb(m, sav, skip, protoff);
369		break;
370#endif
371#ifdef INET
372	case AF_INET:
373		error = ipsec4_common_input_cb(m, sav, skip, protoff);
374		break;
375#endif
376	default:
377		panic("%s: Unexpected address family: %d saidx=%p", __func__,
378		    saidx->dst.sa.sa_family, saidx);
379	}
380	CURVNET_RESTORE();
381	return error;
382bad:
383	CURVNET_RESTORE();
384	if (sav != NULL)
385		key_freesav(&sav);
386	if (m != NULL)
387		m_freem(m);
388	if (xd != NULL)
389		free(xd, M_IPCOMP);
390	if (crp != NULL)
391		crypto_freereq(crp);
392	return error;
393}
394
395/*
396 * IPComp output routine, called by ipsec[46]_perform_request()
397 */
398static int
399ipcomp_output(struct mbuf *m, struct secpolicy *sp, struct secasvar *sav,
400    u_int idx, int skip, int protoff)
401{
402	IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
403	const struct comp_algo *ipcompx;
404	struct cryptop *crp;
405	struct xform_data *xd;
406	crypto_session_t cryptoid;
407	int error, ralen, maxpacketsize;
408
409	SECASVAR_RLOCK_TRACKER;
410
411	IPSEC_ASSERT(sav != NULL, ("null SA"));
412	ipcompx = sav->tdb_compalgxform;
413	IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
414
415	/*
416	 * Do not touch the packet in case our payload to compress
417	 * is lower than the minimal threshold of the compression
418	 * alogrithm.  We will just send out the data uncompressed.
419	 * See RFC 3173, 2.2. Non-Expansion Policy.
420	 */
421	if (m->m_pkthdr.len <= ipcompx->minlen) {
422		IPCOMPSTAT_INC(ipcomps_threshold);
423		return ipsec_process_done(m, sp, sav, idx);
424	}
425
426	ralen = m->m_pkthdr.len - skip;	/* Raw payload length before comp. */
427	IPCOMPSTAT_INC(ipcomps_output);
428
429	/* Check for maximum packet size violations. */
430	switch (sav->sah->saidx.dst.sa.sa_family) {
431#ifdef INET
432	case AF_INET:
433		maxpacketsize = IP_MAXPACKET;
434		break;
435#endif /* INET */
436#ifdef INET6
437	case AF_INET6:
438		maxpacketsize = IPV6_MAXPACKET;
439		break;
440#endif /* INET6 */
441	default:
442		IPCOMPSTAT_INC(ipcomps_nopf);
443		DPRINTF(("%s: unknown/unsupported protocol family %d, "
444		    "IPCA %s/%08lx\n", __func__,
445		    sav->sah->saidx.dst.sa.sa_family,
446		    ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
447		    (u_long) ntohl(sav->spi)));
448		error = EPFNOSUPPORT;
449		goto bad;
450	}
451	if (ralen + skip + IPCOMP_HLENGTH > maxpacketsize) {
452		IPCOMPSTAT_INC(ipcomps_toobig);
453		DPRINTF(("%s: packet in IPCA %s/%08lx got too big "
454		    "(len %u, max len %u)\n", __func__,
455		    ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
456		    (u_long) ntohl(sav->spi),
457		    ralen + skip + IPCOMP_HLENGTH, maxpacketsize));
458		error = EMSGSIZE;
459		goto bad;
460	}
461
462	/* Update the counters */
463	IPCOMPSTAT_ADD(ipcomps_obytes, m->m_pkthdr.len - skip);
464
465	m = m_unshare(m, M_NOWAIT);
466	if (m == NULL) {
467		IPCOMPSTAT_INC(ipcomps_hdrops);
468		DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
469		    __func__, ipsec_address(&sav->sah->saidx.dst, buf,
470		    sizeof(buf)), (u_long) ntohl(sav->spi)));
471		error = ENOBUFS;
472		goto bad;
473	}
474
475	/* Ok now, we can pass to the crypto processing. */
476	SECASVAR_RLOCK(sav);
477	cryptoid = sav->tdb_cryptoid;
478	SECASVAR_RUNLOCK(sav);
479
480	/* Get crypto descriptors */
481	crp = crypto_getreq(cryptoid, M_NOWAIT);
482	if (crp == NULL) {
483		IPCOMPSTAT_INC(ipcomps_crypto);
484		DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
485		error = ENOBUFS;
486		goto bad;
487	}
488
489	/* Compression descriptor */
490	crp->crp_op = CRYPTO_OP_COMPRESS;
491	crp->crp_payload_start = skip;
492	crp->crp_payload_length = ralen;
493
494	/* IPsec-specific opaque crypto info */
495	xd =  malloc(sizeof(struct xform_data), M_IPCOMP, M_NOWAIT | M_ZERO);
496	if (xd == NULL) {
497		IPCOMPSTAT_INC(ipcomps_crypto);
498		DPRINTF(("%s: failed to allocate xform_data\n", __func__));
499		crypto_freereq(crp);
500		error = ENOBUFS;
501		goto bad;
502	}
503
504	xd->sp = sp;
505	xd->sav = sav;
506	xd->idx = idx;
507	xd->skip = skip;
508	xd->protoff = protoff;
509	xd->vnet = curvnet;
510	xd->cryptoid = cryptoid;
511
512	/* Crypto operation descriptor */
513	crp->crp_flags = CRYPTO_F_CBIFSYNC;
514	crypto_use_mbuf(crp, m);
515	crp->crp_callback = ipcomp_output_cb;
516	crp->crp_opaque = xd;
517
518	return crypto_dispatch(crp);
519bad:
520	if (m)
521		m_freem(m);
522	key_freesav(&sav);
523	key_freesp(&sp);
524	return (error);
525}
526
527/*
528 * IPComp output callback from the crypto driver.
529 */
530static int
531ipcomp_output_cb(struct cryptop *crp)
532{
533	IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
534	struct xform_data *xd;
535	struct secpolicy *sp;
536	struct secasvar *sav;
537	struct mbuf *m;
538	crypto_session_t cryptoid;
539	u_int idx;
540	int error, skip, protoff;
541
542	m = crp->crp_buf.cb_mbuf;
543	xd = crp->crp_opaque;
544	CURVNET_SET(xd->vnet);
545	idx = xd->idx;
546	sp = xd->sp;
547	sav = xd->sav;
548	skip = xd->skip;
549	protoff = xd->protoff;
550	cryptoid = xd->cryptoid;
551
552	/* Check for crypto errors */
553	if (crp->crp_etype) {
554		if (crp->crp_etype == EAGAIN) {
555			/* Reset the session ID */
556			if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
557				crypto_freesession(cryptoid);
558			xd->cryptoid = crp->crp_session;
559			CURVNET_RESTORE();
560			return (crypto_dispatch(crp));
561		}
562		IPCOMPSTAT_INC(ipcomps_noxform);
563		DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
564		error = crp->crp_etype;
565		goto bad;
566	}
567	/* Shouldn't happen... */
568	if (m == NULL) {
569		IPCOMPSTAT_INC(ipcomps_crypto);
570		DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
571		error = EINVAL;
572		goto bad;
573	}
574	IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
575
576	if (crp->crp_payload_length > crp->crp_olen) {
577		struct mbuf *mo;
578		struct ipcomp *ipcomp;
579		int roff;
580		uint8_t prot;
581
582		/* Compression helped, inject IPCOMP header. */
583		mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
584		if (mo == NULL) {
585			IPCOMPSTAT_INC(ipcomps_wrap);
586			DPRINTF(("%s: IPCOMP header inject failed "
587			    "for IPCA %s/%08lx\n",
588			    __func__, ipsec_address(&sav->sah->saidx.dst, buf,
589			    sizeof(buf)), (u_long) ntohl(sav->spi)));
590			error = ENOBUFS;
591			goto bad;
592		}
593		ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
594
595		/* Initialize the IPCOMP header */
596		/* XXX alignment always correct? */
597		switch (sav->sah->saidx.dst.sa.sa_family) {
598#ifdef INET
599		case AF_INET:
600			ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
601			break;
602#endif /* INET */
603#ifdef INET6
604		case AF_INET6:
605			ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
606			break;
607#endif
608		}
609		ipcomp->comp_flags = 0;
610		ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
611
612		/* Fix Next Protocol in IPv4/IPv6 header */
613		prot = IPPROTO_IPCOMP;
614		m_copyback(m, protoff, sizeof(u_int8_t),
615		    (u_char *)&prot);
616
617		/* Adjust the length in the IP header */
618		switch (sav->sah->saidx.dst.sa.sa_family) {
619#ifdef INET
620		case AF_INET:
621			mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
622			break;
623#endif /* INET */
624#ifdef INET6
625		case AF_INET6:
626			mtod(m, struct ip6_hdr *)->ip6_plen =
627				htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
628			break;
629#endif /* INET6 */
630		default:
631			IPCOMPSTAT_INC(ipcomps_nopf);
632			DPRINTF(("%s: unknown/unsupported protocol "
633			    "family %d, IPCA %s/%08lx\n", __func__,
634			    sav->sah->saidx.dst.sa.sa_family,
635			    ipsec_address(&sav->sah->saidx.dst, buf,
636				sizeof(buf)), (u_long) ntohl(sav->spi)));
637			error = EPFNOSUPPORT;
638			goto bad;
639		}
640	} else {
641		/* Compression was useless, we have lost time. */
642		IPCOMPSTAT_INC(ipcomps_uncompr);
643		DPRINTF(("%s: compressions was useless %d <= %d\n",
644		    __func__, crp->crp_payload_length, crp->crp_olen));
645		/* XXX remember state to not compress the next couple
646		 *     of packets, RFC 3173, 2.2. Non-Expansion Policy */
647	}
648
649	/* Release the crypto descriptor */
650	free(xd, M_IPCOMP);
651	crypto_freereq(crp);
652
653	/* NB: m is reclaimed by ipsec_process_done. */
654	error = ipsec_process_done(m, sp, sav, idx);
655	CURVNET_RESTORE();
656	return (error);
657bad:
658	if (m)
659		m_freem(m);
660	CURVNET_RESTORE();
661	free(xd, M_IPCOMP);
662	crypto_freereq(crp);
663	key_freesav(&sav);
664	key_freesp(&sp);
665	return (error);
666}
667
668#ifdef INET
669static int
670ipcomp4_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
671    void *arg __unused)
672{
673	union sockaddr_union src, dst;
674	const struct ip *ip;
675
676	if (V_ipcomp_enable == 0)
677		return (0);
678	if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
679		return (0);
680	bzero(&src, sizeof(src));
681	bzero(&dst, sizeof(dst));
682	src.sa.sa_family = dst.sa.sa_family = AF_INET;
683	src.sin.sin_len = dst.sin.sin_len = sizeof(struct sockaddr_in);
684	ip = mtod(m, const struct ip *);
685	src.sin.sin_addr = ip->ip_src;
686	dst.sin.sin_addr = ip->ip_dst;
687	return (ipcomp_encapcheck(&src, &dst));
688}
689
690static const struct encaptab *ipe4_cookie = NULL;
691static const struct encap_config ipv4_encap_cfg = {
692	.proto = -1,
693	.min_length = sizeof(struct ip),
694	.exact_match = sizeof(in_addr_t) << 4,
695	.check = ipcomp4_nonexp_encapcheck,
696	.input = ipcomp_nonexp_input
697};
698#endif
699#ifdef INET6
700static int
701ipcomp6_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
702    void *arg __unused)
703{
704	union sockaddr_union src, dst;
705	const struct ip6_hdr *ip6;
706
707	if (V_ipcomp_enable == 0)
708		return (0);
709	if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
710		return (0);
711	bzero(&src, sizeof(src));
712	bzero(&dst, sizeof(dst));
713	src.sa.sa_family = dst.sa.sa_family = AF_INET;
714	src.sin6.sin6_len = dst.sin6.sin6_len = sizeof(struct sockaddr_in6);
715	ip6 = mtod(m, const struct ip6_hdr *);
716	src.sin6.sin6_addr = ip6->ip6_src;
717	dst.sin6.sin6_addr = ip6->ip6_dst;
718	if (IN6_IS_SCOPE_LINKLOCAL(&src.sin6.sin6_addr)) {
719		/* XXX: sa6_recoverscope() */
720		src.sin6.sin6_scope_id =
721		    ntohs(src.sin6.sin6_addr.s6_addr16[1]);
722		src.sin6.sin6_addr.s6_addr16[1] = 0;
723	}
724	if (IN6_IS_SCOPE_LINKLOCAL(&dst.sin6.sin6_addr)) {
725		/* XXX: sa6_recoverscope() */
726		dst.sin6.sin6_scope_id =
727		    ntohs(dst.sin6.sin6_addr.s6_addr16[1]);
728		dst.sin6.sin6_addr.s6_addr16[1] = 0;
729	}
730	return (ipcomp_encapcheck(&src, &dst));
731}
732
733static const struct encaptab *ipe6_cookie = NULL;
734static const struct encap_config ipv6_encap_cfg = {
735	.proto = -1,
736	.min_length = sizeof(struct ip6_hdr),
737	.exact_match = sizeof(struct in6_addr) << 4,
738	.check = ipcomp6_nonexp_encapcheck,
739	.input = ipcomp_nonexp_input
740};
741#endif
742
743static struct xformsw ipcomp_xformsw = {
744	.xf_type =	XF_IPCOMP,
745	.xf_name =	"IPcomp",
746	.xf_init =	ipcomp_init,
747	.xf_cleanup =	ipcomp_cleanup,
748	.xf_input =	ipcomp_input,
749	.xf_output =	ipcomp_output,
750};
751
752static void
753ipcomp_attach(void)
754{
755
756#ifdef INET
757	ipe4_cookie = ip_encap_attach(&ipv4_encap_cfg, NULL, M_WAITOK);
758#endif
759#ifdef INET6
760	ipe6_cookie = ip6_encap_attach(&ipv6_encap_cfg, NULL, M_WAITOK);
761#endif
762	xform_attach(&ipcomp_xformsw);
763}
764
765static void
766ipcomp_detach(void)
767{
768
769#ifdef INET
770	ip_encap_detach(ipe4_cookie);
771#endif
772#ifdef INET6
773	ip6_encap_detach(ipe6_cookie);
774#endif
775	xform_detach(&ipcomp_xformsw);
776}
777
778SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
779    ipcomp_attach, NULL);
780SYSUNINIT(ipcomp_xform_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
781    ipcomp_detach, NULL);
782