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"
37 #include <sys/param.h>
38 #include <sys/systm.h>
41 #include <sys/mutex.h>
42 #include <sys/socket.h>
43 #include <sys/kernel.h>
44 #include <sys/protosw.h>
45 #include <sys/sysctl.h>
47 #include <netinet/in.h>
48 #include <netinet/in_systm.h>
49 #include <netinet/ip.h>
50 #include <netinet/ip_var.h>
51 #include <netinet/ip_encap.h>
53 #include <net/netisr.h>
56 #include <netipsec/ipsec.h>
57 #include <netipsec/xform.h>
60 #include <netinet/ip6.h>
61 #include <netinet6/ip6_var.h>
62 #include <netipsec/ipsec6.h>
65 #include <netipsec/ipcomp.h>
66 #include <netipsec/ipcomp_var.h>
68 #include <netipsec/key.h>
69 #include <netipsec/key_debug.h>
71 #include <opencrypto/cryptodev.h>
72 #include <opencrypto/deflate.h>
73 #include <opencrypto/xform.h>
75 VNET_DEFINE(int, ipcomp_enable) = 1;
76 VNET_PCPUSTAT_DEFINE(struct ipcompstat, ipcompstat);
77 VNET_PCPUSTAT_SYSINIT(ipcompstat);
80 VNET_PCPUSTAT_SYSUNINIT(ipcompstat);
83 SYSCTL_DECL(_net_inet_ipcomp);
84 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO, ipcomp_enable,
85 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipcomp_enable), 0, "");
86 SYSCTL_VNET_PCPUSTAT(_net_inet_ipcomp, IPSECCTL_STATS, stats,
87 struct ipcompstat, ipcompstat,
88 "IPCOMP statistics (struct ipcompstat, netipsec/ipcomp_var.h");
90 static int ipcomp_input_cb(struct cryptop *crp);
91 static int ipcomp_output_cb(struct cryptop *crp);
94 * RFC 3173 p 2.2. Non-Expansion Policy:
95 * If the total size of a compressed payload and the IPComp header, as
96 * defined in section 3, is not smaller than the size of the original
97 * payload, the IP datagram MUST be sent in the original non-compressed
100 * When we use IPComp in tunnel mode, for small packets we will receive
101 * encapsulated IP-IP datagrams without any compression and without IPComp
105 ipcomp_encapcheck(union sockaddr_union *src, union sockaddr_union *dst)
107 struct secasvar *sav;
109 sav = key_allocsa_tunnel(src, dst, IPPROTO_IPCOMP);
114 if (src->sa.sa_family == AF_INET)
115 return (sizeof(struct in_addr) << 4);
117 return (sizeof(struct in6_addr) << 4);
121 ipcomp_nonexp_input(struct mbuf *m, int off, int proto, void *arg __unused)
137 IPCOMPSTAT_INC(ipcomps_nopf);
139 return (IPPROTO_DONE);
142 IPCOMPSTAT_ADD(ipcomps_ibytes, m->m_pkthdr.len);
143 IPCOMPSTAT_INC(ipcomps_input);
144 netisr_dispatch(isr, m);
145 return (IPPROTO_DONE);
149 * ipcomp_init() is called when an CPI is being set up.
152 ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
154 const struct comp_algo *tcomp;
155 struct cryptoini cric;
157 /* NB: algorithm really comes in alg_enc and not alg_comp! */
158 tcomp = comp_algorithm_lookup(sav->alg_enc);
160 DPRINTF(("%s: unsupported compression algorithm %d\n", __func__,
164 sav->alg_comp = sav->alg_enc; /* set for doing histogram */
165 sav->tdb_xform = xsp;
166 sav->tdb_compalgxform = tcomp;
168 /* Initialize crypto session */
169 bzero(&cric, sizeof (cric));
170 cric.cri_alg = sav->tdb_compalgxform->type;
172 return crypto_newsession(&sav->tdb_cryptoid, &cric, V_crypto_support);
176 * ipcomp_zeroize() used when IPCA is deleted
179 ipcomp_zeroize(struct secasvar *sav)
182 crypto_freesession(sav->tdb_cryptoid);
183 sav->tdb_cryptoid = NULL;
188 * ipcomp_input() gets called to uncompress an input packet
191 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
193 struct xform_data *xd;
194 struct cryptodesc *crdc;
196 struct ipcomp *ipcomp;
198 int error, hlen = IPCOMP_HLENGTH;
201 * Check that the next header of the IPComp is not IPComp again, before
202 * doing any real work. Given it is not possible to do double
203 * compression it means someone is playing tricks on us.
206 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
207 IPCOMPSTAT_INC(ipcomps_hdrops); /*XXX*/
208 DPRINTF(("%s: m_pullup failed\n", __func__));
212 addr = (caddr_t) mtod(m, struct ip *) + skip;
213 ipcomp = (struct ipcomp *)addr;
214 if (ipcomp->comp_nxt == IPPROTO_IPCOMP) {
215 IPCOMPSTAT_INC(ipcomps_pdrops); /* XXX have our own stats? */
216 DPRINTF(("%s: recursive compression detected\n", __func__));
221 /* Get crypto descriptors */
222 crp = crypto_getreq(1);
224 DPRINTF(("%s: no crypto descriptors\n", __func__));
225 IPCOMPSTAT_INC(ipcomps_crypto);
228 /* Get IPsec-specific opaque pointer */
229 xd = malloc(sizeof(*xd), M_XDATA, M_NOWAIT | M_ZERO);
231 DPRINTF(("%s: cannot allocate xform_data\n", __func__));
232 IPCOMPSTAT_INC(ipcomps_crypto);
236 crdc = crp->crp_desc;
238 crdc->crd_skip = skip + hlen;
239 crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
240 crdc->crd_inject = skip;
242 /* Decompression operation */
243 crdc->crd_alg = sav->tdb_compalgxform->type;
246 /* Crypto operation descriptor */
247 crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
248 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
249 crp->crp_buf = (caddr_t) m;
250 crp->crp_callback = ipcomp_input_cb;
251 crp->crp_opaque = (caddr_t) xd;
253 /* These are passed as-is to the callback */
255 xd->protoff = protoff;
260 crp->crp_session = xd->cryptoid = sav->tdb_cryptoid;
261 SECASVAR_UNLOCK(sav);
263 return crypto_dispatch(crp);
271 * IPComp input callback from the crypto driver.
274 ipcomp_input_cb(struct cryptop *crp)
276 IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
277 struct xform_data *xd;
279 struct secasvar *sav;
280 struct secasindex *saidx;
282 crypto_session_t cryptoid;
283 int hlen = IPCOMP_HLENGTH, error, clen;
287 m = (struct mbuf *) crp->crp_buf;
288 xd = (struct xform_data *) crp->crp_opaque;
289 CURVNET_SET(xd->vnet);
292 protoff = xd->protoff;
293 cryptoid = xd->cryptoid;
294 saidx = &sav->sah->saidx;
295 IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
296 saidx->dst.sa.sa_family == AF_INET6,
297 ("unexpected protocol family %u", saidx->dst.sa.sa_family));
299 /* Check for crypto errors */
300 if (crp->crp_etype) {
301 if (crp->crp_etype == EAGAIN) {
302 /* Reset the session ID */
303 if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
304 crypto_freesession(cryptoid);
305 xd->cryptoid = crp->crp_session;
307 return (crypto_dispatch(crp));
309 IPCOMPSTAT_INC(ipcomps_noxform);
310 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
311 error = crp->crp_etype;
314 /* Shouldn't happen... */
316 IPCOMPSTAT_INC(ipcomps_crypto);
317 DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
321 IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
323 clen = crp->crp_olen; /* Length of data after processing */
325 /* Release the crypto descriptors */
326 free(xd, M_XDATA), xd = NULL;
327 crypto_freereq(crp), crp = NULL;
329 /* In case it's not done already, adjust the size of the mbuf chain */
330 m->m_pkthdr.len = clen + hlen + skip;
332 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
333 IPCOMPSTAT_INC(ipcomps_hdrops); /*XXX*/
334 DPRINTF(("%s: m_pullup failed\n", __func__));
335 error = EINVAL; /*XXX*/
339 /* Keep the next protocol field */
340 addr = (caddr_t) mtod(m, struct ip *) + skip;
341 nproto = ((struct ipcomp *) addr)->comp_nxt;
343 /* Remove the IPCOMP header */
344 error = m_striphdr(m, skip, hlen);
346 IPCOMPSTAT_INC(ipcomps_hdrops);
347 DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__,
348 ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
349 (u_long) ntohl(sav->spi)));
353 /* Restore the Next Protocol field */
354 m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
356 switch (saidx->dst.sa.sa_family) {
359 error = ipsec6_common_input_cb(m, sav, skip, protoff);
364 error = ipsec4_common_input_cb(m, sav, skip, protoff);
368 panic("%s: Unexpected address family: %d saidx=%p", __func__,
369 saidx->dst.sa.sa_family, saidx);
387 * IPComp output routine, called by ipsec[46]_perform_request()
390 ipcomp_output(struct mbuf *m, struct secpolicy *sp, struct secasvar *sav,
391 u_int idx, int skip, int protoff)
393 IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
394 const struct comp_algo *ipcompx;
395 struct cryptodesc *crdc;
397 struct xform_data *xd;
398 int error, ralen, maxpacketsize;
400 IPSEC_ASSERT(sav != NULL, ("null SA"));
401 ipcompx = sav->tdb_compalgxform;
402 IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
405 * Do not touch the packet in case our payload to compress
406 * is lower than the minimal threshold of the compression
407 * alogrithm. We will just send out the data uncompressed.
408 * See RFC 3173, 2.2. Non-Expansion Policy.
410 if (m->m_pkthdr.len <= ipcompx->minlen) {
411 IPCOMPSTAT_INC(ipcomps_threshold);
412 return ipsec_process_done(m, sp, sav, idx);
415 ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
416 IPCOMPSTAT_INC(ipcomps_output);
418 /* Check for maximum packet size violations. */
419 switch (sav->sah->saidx.dst.sa.sa_family) {
422 maxpacketsize = IP_MAXPACKET;
427 maxpacketsize = IPV6_MAXPACKET;
431 IPCOMPSTAT_INC(ipcomps_nopf);
432 DPRINTF(("%s: unknown/unsupported protocol family %d, "
433 "IPCA %s/%08lx\n", __func__,
434 sav->sah->saidx.dst.sa.sa_family,
435 ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
436 (u_long) ntohl(sav->spi)));
437 error = EPFNOSUPPORT;
440 if (ralen + skip + IPCOMP_HLENGTH > maxpacketsize) {
441 IPCOMPSTAT_INC(ipcomps_toobig);
442 DPRINTF(("%s: packet in IPCA %s/%08lx got too big "
443 "(len %u, max len %u)\n", __func__,
444 ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
445 (u_long) ntohl(sav->spi),
446 ralen + skip + IPCOMP_HLENGTH, maxpacketsize));
451 /* Update the counters */
452 IPCOMPSTAT_ADD(ipcomps_obytes, m->m_pkthdr.len - skip);
454 m = m_unshare(m, M_NOWAIT);
456 IPCOMPSTAT_INC(ipcomps_hdrops);
457 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
458 __func__, ipsec_address(&sav->sah->saidx.dst, buf,
459 sizeof(buf)), (u_long) ntohl(sav->spi)));
464 /* Ok now, we can pass to the crypto processing. */
466 /* Get crypto descriptors */
467 crp = crypto_getreq(1);
469 IPCOMPSTAT_INC(ipcomps_crypto);
470 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
474 crdc = crp->crp_desc;
476 /* Compression descriptor */
477 crdc->crd_skip = skip;
478 crdc->crd_len = ralen;
479 crdc->crd_flags = CRD_F_COMP;
480 crdc->crd_inject = skip;
482 /* Compression operation */
483 crdc->crd_alg = ipcompx->type;
485 /* IPsec-specific opaque crypto info */
486 xd = malloc(sizeof(struct xform_data), M_XDATA, M_NOWAIT | M_ZERO);
488 IPCOMPSTAT_INC(ipcomps_crypto);
489 DPRINTF(("%s: failed to allocate xform_data\n", __func__));
499 xd->protoff = protoff;
502 /* Crypto operation descriptor */
503 crp->crp_ilen = m->m_pkthdr.len; /* Total input length */
504 crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
505 crp->crp_buf = (caddr_t) m;
506 crp->crp_callback = ipcomp_output_cb;
507 crp->crp_opaque = (caddr_t) xd;
510 crp->crp_session = xd->cryptoid = sav->tdb_cryptoid;
511 SECASVAR_UNLOCK(sav);
513 return crypto_dispatch(crp);
523 * IPComp output callback from the crypto driver.
526 ipcomp_output_cb(struct cryptop *crp)
528 IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
529 struct xform_data *xd;
530 struct secpolicy *sp;
531 struct secasvar *sav;
533 crypto_session_t cryptoid;
535 int error, skip, protoff;
537 m = (struct mbuf *) crp->crp_buf;
538 xd = (struct xform_data *) crp->crp_opaque;
539 CURVNET_SET(xd->vnet);
544 protoff = xd->protoff;
545 cryptoid = xd->cryptoid;
547 /* Check for crypto errors */
548 if (crp->crp_etype) {
549 if (crp->crp_etype == EAGAIN) {
550 /* Reset the session ID */
551 if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
552 crypto_freesession(cryptoid);
553 xd->cryptoid = crp->crp_session;
555 return (crypto_dispatch(crp));
557 IPCOMPSTAT_INC(ipcomps_noxform);
558 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
559 error = crp->crp_etype;
562 /* Shouldn't happen... */
564 IPCOMPSTAT_INC(ipcomps_crypto);
565 DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
569 IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
571 if (crp->crp_ilen - skip > crp->crp_olen) {
573 struct ipcomp *ipcomp;
577 /* Compression helped, inject IPCOMP header. */
578 mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
580 IPCOMPSTAT_INC(ipcomps_wrap);
581 DPRINTF(("%s: IPCOMP header inject failed "
582 "for IPCA %s/%08lx\n",
583 __func__, ipsec_address(&sav->sah->saidx.dst, buf,
584 sizeof(buf)), (u_long) ntohl(sav->spi)));
588 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
590 /* Initialize the IPCOMP header */
591 /* XXX alignment always correct? */
592 switch (sav->sah->saidx.dst.sa.sa_family) {
595 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
600 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
604 ipcomp->comp_flags = 0;
605 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
607 /* Fix Next Protocol in IPv4/IPv6 header */
608 prot = IPPROTO_IPCOMP;
609 m_copyback(m, protoff, sizeof(u_int8_t),
612 /* Adjust the length in the IP header */
613 switch (sav->sah->saidx.dst.sa.sa_family) {
616 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
621 mtod(m, struct ip6_hdr *)->ip6_plen =
622 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
626 IPCOMPSTAT_INC(ipcomps_nopf);
627 DPRINTF(("%s: unknown/unsupported protocol "
628 "family %d, IPCA %s/%08lx\n", __func__,
629 sav->sah->saidx.dst.sa.sa_family,
630 ipsec_address(&sav->sah->saidx.dst, buf,
631 sizeof(buf)), (u_long) ntohl(sav->spi)));
632 error = EPFNOSUPPORT;
636 /* Compression was useless, we have lost time. */
637 IPCOMPSTAT_INC(ipcomps_uncompr);
638 DPRINTF(("%s: compressions was useless %d - %d <= %d\n",
639 __func__, crp->crp_ilen, skip, crp->crp_olen));
640 /* XXX remember state to not compress the next couple
641 * of packets, RFC 3173, 2.2. Non-Expansion Policy */
644 /* Release the crypto descriptor */
648 /* NB: m is reclaimed by ipsec_process_done. */
649 error = ipsec_process_done(m, sp, sav, idx);
665 ipcomp4_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
668 union sockaddr_union src, dst;
671 if (V_ipcomp_enable == 0)
673 if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
675 bzero(&src, sizeof(src));
676 bzero(&dst, sizeof(dst));
677 src.sa.sa_family = dst.sa.sa_family = AF_INET;
678 src.sin.sin_len = dst.sin.sin_len = sizeof(struct sockaddr_in);
679 ip = mtod(m, const struct ip *);
680 src.sin.sin_addr = ip->ip_src;
681 dst.sin.sin_addr = ip->ip_dst;
682 return (ipcomp_encapcheck(&src, &dst));
685 static const struct encaptab *ipe4_cookie = NULL;
686 static const struct encap_config ipv4_encap_cfg = {
688 .min_length = sizeof(struct ip),
689 .exact_match = sizeof(in_addr_t) << 4,
690 .check = ipcomp4_nonexp_encapcheck,
691 .input = ipcomp_nonexp_input
696 ipcomp6_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
699 union sockaddr_union src, dst;
700 const struct ip6_hdr *ip6;
702 if (V_ipcomp_enable == 0)
704 if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
706 bzero(&src, sizeof(src));
707 bzero(&dst, sizeof(dst));
708 src.sa.sa_family = dst.sa.sa_family = AF_INET;
709 src.sin6.sin6_len = dst.sin6.sin6_len = sizeof(struct sockaddr_in6);
710 ip6 = mtod(m, const struct ip6_hdr *);
711 src.sin6.sin6_addr = ip6->ip6_src;
712 dst.sin6.sin6_addr = ip6->ip6_dst;
713 if (IN6_IS_SCOPE_LINKLOCAL(&src.sin6.sin6_addr)) {
714 /* XXX: sa6_recoverscope() */
715 src.sin6.sin6_scope_id =
716 ntohs(src.sin6.sin6_addr.s6_addr16[1]);
717 src.sin6.sin6_addr.s6_addr16[1] = 0;
719 if (IN6_IS_SCOPE_LINKLOCAL(&dst.sin6.sin6_addr)) {
720 /* XXX: sa6_recoverscope() */
721 dst.sin6.sin6_scope_id =
722 ntohs(dst.sin6.sin6_addr.s6_addr16[1]);
723 dst.sin6.sin6_addr.s6_addr16[1] = 0;
725 return (ipcomp_encapcheck(&src, &dst));
728 static const struct encaptab *ipe6_cookie = NULL;
729 static const struct encap_config ipv6_encap_cfg = {
731 .min_length = sizeof(struct ip6_hdr),
732 .exact_match = sizeof(struct in6_addr) << 4,
733 .check = ipcomp6_nonexp_encapcheck,
734 .input = ipcomp_nonexp_input
738 static struct xformsw ipcomp_xformsw = {
739 .xf_type = XF_IPCOMP,
741 .xf_init = ipcomp_init,
742 .xf_zeroize = ipcomp_zeroize,
743 .xf_input = ipcomp_input,
744 .xf_output = ipcomp_output,
752 ipe4_cookie = ip_encap_attach(&ipv4_encap_cfg, NULL, M_WAITOK);
755 ipe6_cookie = ip6_encap_attach(&ipv6_encap_cfg, NULL, M_WAITOK);
757 xform_attach(&ipcomp_xformsw);
765 ip_encap_detach(ipe4_cookie);
768 ip6_encap_detach(ipe6_cookie);
770 xform_detach(&ipcomp_xformsw);
773 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
774 ipcomp_attach, NULL);
775 SYSUNINIT(ipcomp_xform_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
776 ipcomp_detach, NULL);