2 /* $OpenBSD: ip_ipcomp.c,v 1.1 2001/07/05 12:08:52 jjbg Exp $ */
5 * SPDX-License-Identifier: BSD-3-Clause
7 * Copyright (c) 2001 Jean-Jacques Bernard-Gundol (jj@wabbitt.org)
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 /* IP payload compression protocol (IPComp), see RFC 2393 */
35 #include "opt_inet6.h"
36 #include "opt_ipsec.h"
38 #include <sys/param.h>
39 #include <sys/systm.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>
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>
54 #include <net/netisr.h>
57 #include <netipsec/ipsec.h>
58 #include <netipsec/xform.h>
61 #include <netinet/ip6.h>
62 #include <netinet6/ip6_var.h>
63 #include <netipsec/ipsec6.h>
66 #include <netipsec/ipcomp.h>
67 #include <netipsec/ipcomp_var.h>
69 #include <netipsec/key.h>
70 #include <netipsec/key_debug.h>
72 #include <opencrypto/cryptodev.h>
73 #include <opencrypto/deflate.h>
74 #include <opencrypto/xform.h>
76 VNET_DEFINE(int, ipcomp_enable) = 1;
77 VNET_PCPUSTAT_DEFINE(struct ipcompstat, ipcompstat);
78 VNET_PCPUSTAT_SYSINIT(ipcompstat);
81 VNET_PCPUSTAT_SYSUNINIT(ipcompstat);
84 SYSCTL_DECL(_net_inet_ipcomp);
85 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO, ipcomp_enable,
86 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipcomp_enable), 0, "");
87 SYSCTL_VNET_PCPUSTAT(_net_inet_ipcomp, IPSECCTL_STATS, stats,
88 struct ipcompstat, ipcompstat,
89 "IPCOMP statistics (struct ipcompstat, netipsec/ipcomp_var.h");
91 static int ipcomp_input_cb(struct cryptop *crp);
92 static int ipcomp_output_cb(struct cryptop *crp);
95 * RFC 3173 p 2.2. Non-Expansion Policy:
96 * If the total size of a compressed payload and the IPComp header, as
97 * defined in section 3, is not smaller than the size of the original
98 * payload, the IP datagram MUST be sent in the original non-compressed
101 * When we use IPComp in tunnel mode, for small packets we will receive
102 * encapsulated IP-IP datagrams without any compression and without IPComp
106 ipcomp_encapcheck(union sockaddr_union *src, union sockaddr_union *dst)
108 struct secasvar *sav;
110 sav = key_allocsa_tunnel(src, dst, IPPROTO_IPCOMP);
115 if (src->sa.sa_family == AF_INET)
116 return (sizeof(struct in_addr) << 4);
118 return (sizeof(struct in6_addr) << 4);
122 ipcomp_nonexp_input(struct mbuf *m, int off, int proto, void *arg __unused)
138 IPCOMPSTAT_INC(ipcomps_nopf);
140 return (IPPROTO_DONE);
143 IPCOMPSTAT_ADD(ipcomps_ibytes, m->m_pkthdr.len);
144 IPCOMPSTAT_INC(ipcomps_input);
145 netisr_dispatch(isr, m);
146 return (IPPROTO_DONE);
150 * ipcomp_init() is called when an CPI is being set up.
153 ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
155 const struct comp_algo *tcomp;
156 struct cryptoini cric;
158 /* NB: algorithm really comes in alg_enc and not alg_comp! */
159 tcomp = comp_algorithm_lookup(sav->alg_enc);
161 DPRINTF(("%s: unsupported compression algorithm %d\n", __func__,
165 sav->alg_comp = sav->alg_enc; /* set for doing histogram */
166 sav->tdb_xform = xsp;
167 sav->tdb_compalgxform = tcomp;
169 /* Initialize crypto session */
170 bzero(&cric, sizeof (cric));
171 cric.cri_alg = sav->tdb_compalgxform->type;
173 return crypto_newsession(&sav->tdb_cryptoid, &cric, V_crypto_support);
177 * ipcomp_zeroize() used when IPCA is deleted
180 ipcomp_zeroize(struct secasvar *sav)
183 crypto_freesession(sav->tdb_cryptoid);
184 sav->tdb_cryptoid = NULL;
189 * ipcomp_input() gets called to uncompress an input packet
192 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
194 struct xform_data *xd;
195 struct cryptodesc *crdc;
197 struct ipcomp *ipcomp;
199 int error, hlen = IPCOMP_HLENGTH;
202 * Check that the next header of the IPComp is not IPComp again, before
203 * doing any real work. Given it is not possible to do double
204 * compression it means someone is playing tricks on us.
207 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
208 IPCOMPSTAT_INC(ipcomps_hdrops); /*XXX*/
209 DPRINTF(("%s: m_pullup failed\n", __func__));
213 addr = (caddr_t) mtod(m, struct ip *) + skip;
214 ipcomp = (struct ipcomp *)addr;
215 if (ipcomp->comp_nxt == IPPROTO_IPCOMP) {
216 IPCOMPSTAT_INC(ipcomps_pdrops); /* XXX have our own stats? */
217 DPRINTF(("%s: recursive compression detected\n", __func__));
222 /* Get crypto descriptors */
223 crp = crypto_getreq(1);
225 DPRINTF(("%s: no crypto descriptors\n", __func__));
226 IPCOMPSTAT_INC(ipcomps_crypto);
229 /* Get IPsec-specific opaque pointer */
230 xd = malloc(sizeof(*xd), M_XDATA, M_NOWAIT | M_ZERO);
232 DPRINTF(("%s: cannot allocate xform_data\n", __func__));
233 IPCOMPSTAT_INC(ipcomps_crypto);
237 crdc = crp->crp_desc;
239 crdc->crd_skip = skip + hlen;
240 crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
241 crdc->crd_inject = skip;
243 /* Decompression operation */
244 crdc->crd_alg = sav->tdb_compalgxform->type;
247 /* Crypto operation descriptor */
248 crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
249 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
250 crp->crp_buf = (caddr_t) m;
251 crp->crp_callback = ipcomp_input_cb;
252 crp->crp_opaque = (caddr_t) xd;
254 /* These are passed as-is to the callback */
256 xd->protoff = protoff;
261 crp->crp_session = xd->cryptoid = sav->tdb_cryptoid;
262 SECASVAR_UNLOCK(sav);
264 return crypto_dispatch(crp);
272 * IPComp input callback from the crypto driver.
275 ipcomp_input_cb(struct cryptop *crp)
277 IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
278 struct xform_data *xd;
280 struct secasvar *sav;
281 struct secasindex *saidx;
283 crypto_session_t cryptoid;
284 int hlen = IPCOMP_HLENGTH, error, clen;
288 m = (struct mbuf *) crp->crp_buf;
289 xd = (struct xform_data *) crp->crp_opaque;
290 CURVNET_SET(xd->vnet);
293 protoff = xd->protoff;
294 cryptoid = xd->cryptoid;
295 saidx = &sav->sah->saidx;
296 IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
297 saidx->dst.sa.sa_family == AF_INET6,
298 ("unexpected protocol family %u", saidx->dst.sa.sa_family));
300 /* Check for crypto errors */
301 if (crp->crp_etype) {
302 if (crp->crp_etype == EAGAIN) {
303 /* Reset the session ID */
304 if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
305 crypto_freesession(cryptoid);
306 xd->cryptoid = crp->crp_session;
308 return (crypto_dispatch(crp));
310 IPCOMPSTAT_INC(ipcomps_noxform);
311 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
312 error = crp->crp_etype;
315 /* Shouldn't happen... */
317 IPCOMPSTAT_INC(ipcomps_crypto);
318 DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
322 IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
324 clen = crp->crp_olen; /* Length of data after processing */
326 /* Release the crypto descriptors */
327 free(xd, M_XDATA), xd = NULL;
328 crypto_freereq(crp), crp = NULL;
330 /* In case it's not done already, adjust the size of the mbuf chain */
331 m->m_pkthdr.len = clen + hlen + skip;
333 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
334 IPCOMPSTAT_INC(ipcomps_hdrops); /*XXX*/
335 DPRINTF(("%s: m_pullup failed\n", __func__));
336 error = EINVAL; /*XXX*/
340 /* Keep the next protocol field */
341 addr = (caddr_t) mtod(m, struct ip *) + skip;
342 nproto = ((struct ipcomp *) addr)->comp_nxt;
344 /* Remove the IPCOMP header */
345 error = m_striphdr(m, skip, hlen);
347 IPCOMPSTAT_INC(ipcomps_hdrops);
348 DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__,
349 ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
350 (u_long) ntohl(sav->spi)));
354 /* Restore the Next Protocol field */
355 m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
357 switch (saidx->dst.sa.sa_family) {
360 error = ipsec6_common_input_cb(m, sav, skip, protoff);
365 error = ipsec4_common_input_cb(m, sav, skip, protoff);
369 panic("%s: Unexpected address family: %d saidx=%p", __func__,
370 saidx->dst.sa.sa_family, saidx);
388 * IPComp output routine, called by ipsec[46]_perform_request()
391 ipcomp_output(struct mbuf *m, struct secpolicy *sp, struct secasvar *sav,
392 u_int idx, int skip, int protoff)
394 IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
395 const struct comp_algo *ipcompx;
396 struct cryptodesc *crdc;
398 struct xform_data *xd;
399 int error, ralen, maxpacketsize;
401 IPSEC_ASSERT(sav != NULL, ("null SA"));
402 ipcompx = sav->tdb_compalgxform;
403 IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
406 * Do not touch the packet in case our payload to compress
407 * is lower than the minimal threshold of the compression
408 * alogrithm. We will just send out the data uncompressed.
409 * See RFC 3173, 2.2. Non-Expansion Policy.
411 if (m->m_pkthdr.len <= ipcompx->minlen) {
412 IPCOMPSTAT_INC(ipcomps_threshold);
413 return ipsec_process_done(m, sp, sav, idx);
416 ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
417 IPCOMPSTAT_INC(ipcomps_output);
419 /* Check for maximum packet size violations. */
420 switch (sav->sah->saidx.dst.sa.sa_family) {
423 maxpacketsize = IP_MAXPACKET;
428 maxpacketsize = IPV6_MAXPACKET;
432 IPCOMPSTAT_INC(ipcomps_nopf);
433 DPRINTF(("%s: unknown/unsupported protocol family %d, "
434 "IPCA %s/%08lx\n", __func__,
435 sav->sah->saidx.dst.sa.sa_family,
436 ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
437 (u_long) ntohl(sav->spi)));
438 error = EPFNOSUPPORT;
441 if (ralen + skip + IPCOMP_HLENGTH > maxpacketsize) {
442 IPCOMPSTAT_INC(ipcomps_toobig);
443 DPRINTF(("%s: packet in IPCA %s/%08lx got too big "
444 "(len %u, max len %u)\n", __func__,
445 ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
446 (u_long) ntohl(sav->spi),
447 ralen + skip + IPCOMP_HLENGTH, maxpacketsize));
452 /* Update the counters */
453 IPCOMPSTAT_ADD(ipcomps_obytes, m->m_pkthdr.len - skip);
455 m = m_unshare(m, M_NOWAIT);
457 IPCOMPSTAT_INC(ipcomps_hdrops);
458 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
459 __func__, ipsec_address(&sav->sah->saidx.dst, buf,
460 sizeof(buf)), (u_long) ntohl(sav->spi)));
465 /* Ok now, we can pass to the crypto processing. */
467 /* Get crypto descriptors */
468 crp = crypto_getreq(1);
470 IPCOMPSTAT_INC(ipcomps_crypto);
471 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
475 crdc = crp->crp_desc;
477 /* Compression descriptor */
478 crdc->crd_skip = skip;
479 crdc->crd_len = ralen;
480 crdc->crd_flags = CRD_F_COMP;
481 crdc->crd_inject = skip;
483 /* Compression operation */
484 crdc->crd_alg = ipcompx->type;
486 /* IPsec-specific opaque crypto info */
487 xd = malloc(sizeof(struct xform_data), M_XDATA, M_NOWAIT | M_ZERO);
489 IPCOMPSTAT_INC(ipcomps_crypto);
490 DPRINTF(("%s: failed to allocate xform_data\n", __func__));
500 xd->protoff = protoff;
503 /* Crypto operation descriptor */
504 crp->crp_ilen = m->m_pkthdr.len; /* Total input length */
505 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
506 crp->crp_buf = (caddr_t) m;
507 crp->crp_callback = ipcomp_output_cb;
508 crp->crp_opaque = (caddr_t) xd;
511 crp->crp_session = xd->cryptoid = sav->tdb_cryptoid;
512 SECASVAR_UNLOCK(sav);
514 return crypto_dispatch(crp);
524 * IPComp output callback from the crypto driver.
527 ipcomp_output_cb(struct cryptop *crp)
529 IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
530 struct xform_data *xd;
531 struct secpolicy *sp;
532 struct secasvar *sav;
534 crypto_session_t cryptoid;
536 int error, skip, protoff;
538 m = (struct mbuf *) crp->crp_buf;
539 xd = (struct xform_data *) crp->crp_opaque;
540 CURVNET_SET(xd->vnet);
545 protoff = xd->protoff;
546 cryptoid = xd->cryptoid;
548 /* Check for crypto errors */
549 if (crp->crp_etype) {
550 if (crp->crp_etype == EAGAIN) {
551 /* Reset the session ID */
552 if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
553 crypto_freesession(cryptoid);
554 xd->cryptoid = crp->crp_session;
556 return (crypto_dispatch(crp));
558 IPCOMPSTAT_INC(ipcomps_noxform);
559 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
560 error = crp->crp_etype;
563 /* Shouldn't happen... */
565 IPCOMPSTAT_INC(ipcomps_crypto);
566 DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
570 IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
572 if (crp->crp_ilen - skip > crp->crp_olen) {
574 struct ipcomp *ipcomp;
578 /* Compression helped, inject IPCOMP header. */
579 mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
581 IPCOMPSTAT_INC(ipcomps_wrap);
582 DPRINTF(("%s: IPCOMP header inject failed "
583 "for IPCA %s/%08lx\n",
584 __func__, ipsec_address(&sav->sah->saidx.dst, buf,
585 sizeof(buf)), (u_long) ntohl(sav->spi)));
589 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
591 /* Initialize the IPCOMP header */
592 /* XXX alignment always correct? */
593 switch (sav->sah->saidx.dst.sa.sa_family) {
596 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
601 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
605 ipcomp->comp_flags = 0;
606 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
608 /* Fix Next Protocol in IPv4/IPv6 header */
609 prot = IPPROTO_IPCOMP;
610 m_copyback(m, protoff, sizeof(u_int8_t),
613 /* Adjust the length in the IP header */
614 switch (sav->sah->saidx.dst.sa.sa_family) {
617 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
622 mtod(m, struct ip6_hdr *)->ip6_plen =
623 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
627 IPCOMPSTAT_INC(ipcomps_nopf);
628 DPRINTF(("%s: unknown/unsupported protocol "
629 "family %d, IPCA %s/%08lx\n", __func__,
630 sav->sah->saidx.dst.sa.sa_family,
631 ipsec_address(&sav->sah->saidx.dst, buf,
632 sizeof(buf)), (u_long) ntohl(sav->spi)));
633 error = EPFNOSUPPORT;
637 /* Compression was useless, we have lost time. */
638 IPCOMPSTAT_INC(ipcomps_uncompr);
639 DPRINTF(("%s: compressions was useless %d - %d <= %d\n",
640 __func__, crp->crp_ilen, skip, crp->crp_olen));
641 /* XXX remember state to not compress the next couple
642 * of packets, RFC 3173, 2.2. Non-Expansion Policy */
645 /* Release the crypto descriptor */
649 /* NB: m is reclaimed by ipsec_process_done. */
650 error = ipsec_process_done(m, sp, sav, idx);
666 ipcomp4_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
669 union sockaddr_union src, dst;
672 if (V_ipcomp_enable == 0)
674 if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
676 bzero(&src, sizeof(src));
677 bzero(&dst, sizeof(dst));
678 src.sa.sa_family = dst.sa.sa_family = AF_INET;
679 src.sin.sin_len = dst.sin.sin_len = sizeof(struct sockaddr_in);
680 ip = mtod(m, const struct ip *);
681 src.sin.sin_addr = ip->ip_src;
682 dst.sin.sin_addr = ip->ip_dst;
683 return (ipcomp_encapcheck(&src, &dst));
686 static const struct encaptab *ipe4_cookie = NULL;
687 static const struct encap_config ipv4_encap_cfg = {
689 .min_length = sizeof(struct ip),
690 .exact_match = sizeof(in_addr_t) << 4,
691 .check = ipcomp4_nonexp_encapcheck,
692 .input = ipcomp_nonexp_input
697 ipcomp6_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
700 union sockaddr_union src, dst;
701 const struct ip6_hdr *ip6;
703 if (V_ipcomp_enable == 0)
705 if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
707 bzero(&src, sizeof(src));
708 bzero(&dst, sizeof(dst));
709 src.sa.sa_family = dst.sa.sa_family = AF_INET;
710 src.sin6.sin6_len = dst.sin6.sin6_len = sizeof(struct sockaddr_in6);
711 ip6 = mtod(m, const struct ip6_hdr *);
712 src.sin6.sin6_addr = ip6->ip6_src;
713 dst.sin6.sin6_addr = ip6->ip6_dst;
714 if (IN6_IS_SCOPE_LINKLOCAL(&src.sin6.sin6_addr)) {
715 /* XXX: sa6_recoverscope() */
716 src.sin6.sin6_scope_id =
717 ntohs(src.sin6.sin6_addr.s6_addr16[1]);
718 src.sin6.sin6_addr.s6_addr16[1] = 0;
720 if (IN6_IS_SCOPE_LINKLOCAL(&dst.sin6.sin6_addr)) {
721 /* XXX: sa6_recoverscope() */
722 dst.sin6.sin6_scope_id =
723 ntohs(dst.sin6.sin6_addr.s6_addr16[1]);
724 dst.sin6.sin6_addr.s6_addr16[1] = 0;
726 return (ipcomp_encapcheck(&src, &dst));
729 static const struct encaptab *ipe6_cookie = NULL;
730 static const struct encap_config ipv6_encap_cfg = {
732 .min_length = sizeof(struct ip6_hdr),
733 .exact_match = sizeof(struct in6_addr) << 4,
734 .check = ipcomp6_nonexp_encapcheck,
735 .input = ipcomp_nonexp_input
739 static struct xformsw ipcomp_xformsw = {
740 .xf_type = XF_IPCOMP,
742 .xf_init = ipcomp_init,
743 .xf_zeroize = ipcomp_zeroize,
744 .xf_input = ipcomp_input,
745 .xf_output = ipcomp_output,
753 ipe4_cookie = ip_encap_attach(&ipv4_encap_cfg, NULL, M_WAITOK);
756 ipe6_cookie = ip6_encap_attach(&ipv6_encap_cfg, NULL, M_WAITOK);
758 xform_attach(&ipcomp_xformsw);
766 ip_encap_detach(ipe4_cookie);
769 ip6_encap_detach(ipe6_cookie);
771 xform_detach(&ipcomp_xformsw);
774 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
775 ipcomp_attach, NULL);
776 SYSUNINIT(ipcomp_xform_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
777 ipcomp_detach, NULL);