2 /* $OpenBSD: ip_ipcomp.c,v 1.1 2001/07/05 12:08:52 jjbg Exp $ */
5 * Copyright (c) 2001 Jean-Jacques Bernard-Gundol (jj@wabbitt.org)
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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.
31 /* IP payload compression protocol (IPComp), see RFC 2393 */
33 #include "opt_inet6.h"
35 #include <sys/param.h>
36 #include <sys/systm.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>
46 #include <netinet/in.h>
47 #include <netinet/in_systm.h>
48 #include <netinet/ip.h>
49 #include <netinet/ip_var.h>
53 #include <netipsec/ipsec.h>
54 #include <netipsec/xform.h>
57 #include <netinet/ip6.h>
58 #include <netipsec/ipsec6.h>
61 #include <netipsec/ipcomp.h>
62 #include <netipsec/ipcomp_var.h>
64 #include <netipsec/key.h>
65 #include <netipsec/key_debug.h>
67 #include <opencrypto/cryptodev.h>
68 #include <opencrypto/deflate.h>
69 #include <opencrypto/xform.h>
71 VNET_DEFINE(int, ipcomp_enable) = 1;
72 VNET_PCPUSTAT_DEFINE(struct ipcompstat, ipcompstat);
73 VNET_PCPUSTAT_SYSINIT(ipcompstat);
76 VNET_PCPUSTAT_SYSUNINIT(ipcompstat);
79 SYSCTL_DECL(_net_inet_ipcomp);
80 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO, ipcomp_enable,
81 CTLFLAG_VNET | 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");
86 static int ipcomp_input_cb(struct cryptop *crp);
87 static int ipcomp_output_cb(struct cryptop *crp);
90 ipcomp_algorithm_lookup(int alg)
92 if (alg >= IPCOMP_ALG_MAX)
95 case SADB_X_CALG_DEFLATE:
96 return &comp_algo_deflate;
102 * ipcomp_init() is called when an CPI is being set up.
105 ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
107 struct comp_algo *tcomp;
108 struct cryptoini cric;
110 /* NB: algorithm really comes in alg_enc and not alg_comp! */
111 tcomp = ipcomp_algorithm_lookup(sav->alg_enc);
113 DPRINTF(("%s: unsupported compression algorithm %d\n", __func__,
117 sav->alg_comp = sav->alg_enc; /* set for doing histogram */
118 sav->tdb_xform = xsp;
119 sav->tdb_compalgxform = tcomp;
121 /* Initialize crypto session */
122 bzero(&cric, sizeof (cric));
123 cric.cri_alg = sav->tdb_compalgxform->type;
125 return crypto_newsession(&sav->tdb_cryptoid, &cric, V_crypto_support);
129 * ipcomp_zeroize() used when IPCA is deleted
132 ipcomp_zeroize(struct secasvar *sav)
136 err = crypto_freesession(sav->tdb_cryptoid);
137 sav->tdb_cryptoid = 0;
142 * ipcomp_input() gets called to uncompress an input packet
145 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
147 struct tdb_crypto *tc;
148 struct cryptodesc *crdc;
150 struct ipcomp *ipcomp;
152 int hlen = IPCOMP_HLENGTH;
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.
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__));
164 addr = (caddr_t) mtod(m, struct ip *) + skip;
165 ipcomp = (struct ipcomp *)addr;
166 if (ipcomp->comp_nxt == IPPROTO_IPCOMP) {
168 IPCOMPSTAT_INC(ipcomps_pdrops); /* XXX have our own stats? */
169 DPRINTF(("%s: recursive compression detected\n", __func__));
173 /* Get crypto descriptors */
174 crp = crypto_getreq(1);
177 DPRINTF(("%s: no crypto descriptors\n", __func__));
178 IPCOMPSTAT_INC(ipcomps_crypto);
181 /* Get IPsec-specific opaque pointer */
182 tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO);
186 DPRINTF(("%s: cannot allocate tdb_crypto\n", __func__));
187 IPCOMPSTAT_INC(ipcomps_crypto);
190 crdc = crp->crp_desc;
192 crdc->crd_skip = skip + hlen;
193 crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
194 crdc->crd_inject = skip;
198 /* Decompression operation */
199 crdc->crd_alg = sav->tdb_compalgxform->type;
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;
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;
218 return crypto_dispatch(crp);
222 * IPComp input callback from the crypto driver.
225 ipcomp_input_cb(struct cryptop *crp)
227 struct cryptodesc *crd;
228 struct tdb_crypto *tc;
231 struct secasvar *sav;
232 struct secasindex *saidx;
233 int hlen = IPCOMP_HLENGTH, error, clen;
239 tc = (struct tdb_crypto *) crp->crp_opaque;
240 IPSEC_ASSERT(tc != NULL, ("null opaque crypto data area!"));
242 protoff = tc->tc_protoff;
243 m = (struct mbuf *) crp->crp_buf;
246 IPSEC_ASSERT(sav != NULL, ("null SA!"));
248 saidx = &sav->sah->saidx;
249 IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
250 saidx->dst.sa.sa_family == AF_INET6,
251 ("unexpected protocol family %u", saidx->dst.sa.sa_family));
253 /* Check for crypto errors */
254 if (crp->crp_etype) {
255 /* Reset the session ID */
256 if (sav->tdb_cryptoid != 0)
257 sav->tdb_cryptoid = crp->crp_sid;
259 if (crp->crp_etype == EAGAIN) {
260 return crypto_dispatch(crp);
262 IPCOMPSTAT_INC(ipcomps_noxform);
263 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
264 error = crp->crp_etype;
267 /* Shouldn't happen... */
269 IPCOMPSTAT_INC(ipcomps_crypto);
270 DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
274 IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
276 clen = crp->crp_olen; /* Length of data after processing */
278 /* Release the crypto descriptors */
279 free(tc, M_XDATA), tc = NULL;
280 crypto_freereq(crp), crp = NULL;
282 /* In case it's not done already, adjust the size of the mbuf chain */
283 m->m_pkthdr.len = clen + hlen + skip;
285 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) {
286 IPCOMPSTAT_INC(ipcomps_hdrops); /*XXX*/
287 DPRINTF(("%s: m_pullup failed\n", __func__));
288 error = EINVAL; /*XXX*/
292 /* Keep the next protocol field */
293 addr = (caddr_t) mtod(m, struct ip *) + skip;
294 nproto = ((struct ipcomp *) addr)->comp_nxt;
296 /* Remove the IPCOMP header */
297 error = m_striphdr(m, skip, hlen);
299 IPCOMPSTAT_INC(ipcomps_hdrops);
300 DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__,
301 ipsec_address(&sav->sah->saidx.dst),
302 (u_long) ntohl(sav->spi)));
306 /* Restore the Next Protocol field */
307 m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
309 switch (saidx->dst.sa.sa_family) {
312 error = ipsec6_common_input_cb(m, sav, skip, protoff);
317 error = ipsec4_common_input_cb(m, sav, skip, protoff);
321 panic("%s: Unexpected address family: %d saidx=%p", __func__,
322 saidx->dst.sa.sa_family, saidx);
340 * IPComp output routine, called by ipsec[46]_process_packet()
345 struct ipsecrequest *isr,
351 struct secasvar *sav;
352 struct comp_algo *ipcompx;
353 int error, ralen, maxpacketsize;
354 struct cryptodesc *crdc;
356 struct tdb_crypto *tc;
359 IPSEC_ASSERT(sav != NULL, ("null SA"));
360 ipcompx = sav->tdb_compalgxform;
361 IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
364 * Do not touch the packet in case our payload to compress
365 * is lower than the minimal threshold of the compression
366 * alogrithm. We will just send out the data uncompressed.
367 * See RFC 3173, 2.2. Non-Expansion Policy.
369 if (m->m_pkthdr.len <= ipcompx->minlen) {
370 IPCOMPSTAT_INC(ipcomps_threshold);
371 return ipsec_process_done(m, isr);
374 ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
375 IPCOMPSTAT_INC(ipcomps_output);
377 /* Check for maximum packet size violations. */
378 switch (sav->sah->saidx.dst.sa.sa_family) {
381 maxpacketsize = IP_MAXPACKET;
386 maxpacketsize = IPV6_MAXPACKET;
390 IPCOMPSTAT_INC(ipcomps_nopf);
391 DPRINTF(("%s: unknown/unsupported protocol family %d, "
392 "IPCA %s/%08lx\n", __func__,
393 sav->sah->saidx.dst.sa.sa_family,
394 ipsec_address(&sav->sah->saidx.dst),
395 (u_long) ntohl(sav->spi)));
396 error = EPFNOSUPPORT;
399 if (ralen + skip + IPCOMP_HLENGTH > maxpacketsize) {
400 IPCOMPSTAT_INC(ipcomps_toobig);
401 DPRINTF(("%s: packet in IPCA %s/%08lx got too big "
402 "(len %u, max len %u)\n", __func__,
403 ipsec_address(&sav->sah->saidx.dst),
404 (u_long) ntohl(sav->spi),
405 ralen + skip + IPCOMP_HLENGTH, maxpacketsize));
410 /* Update the counters */
411 IPCOMPSTAT_ADD(ipcomps_obytes, m->m_pkthdr.len - skip);
413 m = m_unshare(m, M_NOWAIT);
415 IPCOMPSTAT_INC(ipcomps_hdrops);
416 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
417 __func__, ipsec_address(&sav->sah->saidx.dst),
418 (u_long) ntohl(sav->spi)));
423 /* Ok now, we can pass to the crypto processing. */
425 /* Get crypto descriptors */
426 crp = crypto_getreq(1);
428 IPCOMPSTAT_INC(ipcomps_crypto);
429 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
433 crdc = crp->crp_desc;
435 /* Compression descriptor */
436 crdc->crd_skip = skip;
437 crdc->crd_len = ralen;
438 crdc->crd_flags = CRD_F_COMP;
439 crdc->crd_inject = skip;
441 /* Compression operation */
442 crdc->crd_alg = ipcompx->type;
444 /* IPsec-specific opaque crypto info */
445 tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto),
446 M_XDATA, M_NOWAIT|M_ZERO);
448 IPCOMPSTAT_INC(ipcomps_crypto);
449 DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__));
458 tc->tc_spi = sav->spi;
459 tc->tc_dst = sav->sah->saidx.dst;
460 tc->tc_proto = sav->sah->saidx.proto;
461 tc->tc_protoff = protoff;
464 /* Crypto operation descriptor */
465 crp->crp_ilen = m->m_pkthdr.len; /* Total input length */
466 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
467 crp->crp_buf = (caddr_t) m;
468 crp->crp_callback = ipcomp_output_cb;
469 crp->crp_opaque = (caddr_t) tc;
470 crp->crp_sid = sav->tdb_cryptoid;
472 return crypto_dispatch(crp);
480 * IPComp output callback from the crypto driver.
483 ipcomp_output_cb(struct cryptop *crp)
485 struct tdb_crypto *tc;
486 struct ipsecrequest *isr;
487 struct secasvar *sav;
491 tc = (struct tdb_crypto *) crp->crp_opaque;
492 IPSEC_ASSERT(tc != NULL, ("null opaque data area!"));
493 m = (struct mbuf *) crp->crp_buf;
497 IPSECREQUEST_LOCK(isr);
499 /* With the isr lock released SA pointer can be updated. */
500 if (sav != isr->sav) {
501 IPCOMPSTAT_INC(ipcomps_notdb);
502 DPRINTF(("%s: SA expired while in crypto\n", __func__));
503 error = ENOBUFS; /*XXX*/
507 /* Check for crypto errors */
508 if (crp->crp_etype) {
509 /* Reset the session ID */
510 if (sav->tdb_cryptoid != 0)
511 sav->tdb_cryptoid = crp->crp_sid;
513 if (crp->crp_etype == EAGAIN) {
514 IPSECREQUEST_UNLOCK(isr);
515 return crypto_dispatch(crp);
517 IPCOMPSTAT_INC(ipcomps_noxform);
518 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
519 error = crp->crp_etype;
522 /* Shouldn't happen... */
524 IPCOMPSTAT_INC(ipcomps_crypto);
525 DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
529 IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
531 if (crp->crp_ilen - skip > crp->crp_olen) {
533 struct ipcomp *ipcomp;
537 /* Compression helped, inject IPCOMP header. */
538 mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
540 IPCOMPSTAT_INC(ipcomps_wrap);
541 DPRINTF(("%s: IPCOMP header inject failed for IPCA %s/%08lx\n",
542 __func__, ipsec_address(&sav->sah->saidx.dst),
543 (u_long) ntohl(sav->spi)));
547 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
549 /* Initialize the IPCOMP header */
550 /* XXX alignment always correct? */
551 switch (sav->sah->saidx.dst.sa.sa_family) {
554 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
559 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
563 ipcomp->comp_flags = 0;
564 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
566 /* Fix Next Protocol in IPv4/IPv6 header */
567 prot = IPPROTO_IPCOMP;
568 m_copyback(m, tc->tc_protoff, sizeof(u_int8_t),
571 /* Adjust the length in the IP header */
572 switch (sav->sah->saidx.dst.sa.sa_family) {
575 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
580 mtod(m, struct ip6_hdr *)->ip6_plen =
581 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
585 IPCOMPSTAT_INC(ipcomps_nopf);
586 DPRINTF(("%s: unknown/unsupported protocol "
587 "family %d, IPCA %s/%08lx\n", __func__,
588 sav->sah->saidx.dst.sa.sa_family,
589 ipsec_address(&sav->sah->saidx.dst),
590 (u_long) ntohl(sav->spi)));
591 error = EPFNOSUPPORT;
595 /* Compression was useless, we have lost time. */
596 IPCOMPSTAT_INC(ipcomps_uncompr);
597 DPRINTF(("%s: compressions was useless %d - %d <= %d\n",
598 __func__, crp->crp_ilen, skip, crp->crp_olen));
599 /* XXX remember state to not compress the next couple
600 * of packets, RFC 3173, 2.2. Non-Expansion Policy */
603 /* Release the crypto descriptor */
607 /* NB: m is reclaimed by ipsec_process_done. */
608 error = ipsec_process_done(m, isr);
610 IPSECREQUEST_UNLOCK(isr);
615 IPSECREQUEST_UNLOCK(isr);
623 static struct xformsw ipcomp_xformsw = {
624 XF_IPCOMP, XFT_COMP, "IPcomp",
625 ipcomp_init, ipcomp_zeroize, ipcomp_input,
633 xform_register(&ipcomp_xformsw);
636 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipcomp_attach, NULL);