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
78 VNET_DEFINE(int, ipcomp_enable) = 1;
79 VNET_PCPUSTAT_DEFINE(struct ipcompstat, ipcompstat);
80 VNET_PCPUSTAT_SYSINIT(ipcompstat);
81
82 #ifdef VIMAGE
83 VNET_PCPUSTAT_SYSUNINIT(ipcompstat);
84 #endif /* VIMAGE */
85
86 SYSCTL_DECL(_net_inet_ipcomp);
87 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO, ipcomp_enable,
88 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipcomp_enable), 0, "");
89 SYSCTL_VNET_PCPUSTAT(_net_inet_ipcomp, IPSECCTL_STATS, stats,
90 struct ipcompstat, ipcompstat,
91 "IPCOMP statistics (struct ipcompstat, netipsec/ipcomp_var.h");
92
93 static MALLOC_DEFINE(M_IPCOMP, "ipcomp", "IPCOMP");
94
95 static int ipcomp_input_cb(struct cryptop *crp);
96 static 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 */
109 static int
ipcomp_encapcheck(union sockaddr_union * src,union sockaddr_union * dst)110 ipcomp_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
125 static int
ipcomp_nonexp_input(struct mbuf * m,int off,int proto,void * arg __unused)126 ipcomp_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 */
158 static int
ipcomp_init(struct secasvar * sav,struct xformsw * xsp)159 ipcomp_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 */
186 static void
ipcomp_cleanup(struct secasvar * sav)187 ipcomp_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 */
197 static int
ipcomp_input(struct mbuf * m,struct secasvar * sav,int skip,int protoff)198 ipcomp_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);
273 bad:
274 m_freem(m);
275 key_freesav(&sav);
276 return (error);
277 }
278
279 /*
280 * IPComp input callback from the crypto driver.
281 */
282 static int
ipcomp_input_cb(struct cryptop * crp)283 ipcomp_input_cb(struct cryptop *crp)
284 {
285 IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
286 struct rm_priotracker sahtree_tracker;
287 struct xform_data *xd;
288 struct mbuf *m;
289 struct secasvar *sav;
290 struct secasindex *saidx;
291 caddr_t addr;
292 crypto_session_t cryptoid;
293 int hlen = IPCOMP_HLENGTH, error, clen;
294 int skip, protoff;
295 uint8_t nproto;
296
297 m = crp->crp_buf.cb_mbuf;
298 xd = crp->crp_opaque;
299 CURVNET_SET(xd->vnet);
300 sav = xd->sav;
301 skip = xd->skip;
302 protoff = xd->protoff;
303 cryptoid = xd->cryptoid;
304 ipsec_sahtree_rlock(&sahtree_tracker);
305 if (sav->state >= SADB_SASTATE_DEAD) {
306 /* saidx is freed */
307 DPRINTF(("%s: dead SA %p spi %#x\n", __func__, sav, sav->spi));
308 IPCOMPSTAT_INC(ipcomps_notdb);
309 error = ESRCH;
310 goto bad;
311 }
312 saidx = &sav->sah->saidx;
313 IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
314 saidx->dst.sa.sa_family == AF_INET6,
315 ("unexpected protocol family %u", saidx->dst.sa.sa_family));
316
317 /* Check for crypto errors */
318 if (crp->crp_etype) {
319 if (crp->crp_etype == EAGAIN) {
320 /* Reset the session ID */
321 if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
322 crypto_freesession(cryptoid);
323 xd->cryptoid = crp->crp_session;
324 CURVNET_RESTORE();
325 return (crypto_dispatch(crp));
326 }
327 IPCOMPSTAT_INC(ipcomps_noxform);
328 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
329 error = crp->crp_etype;
330 goto bad;
331 }
332 /* Shouldn't happen... */
333 if (m == NULL) {
334 IPCOMPSTAT_INC(ipcomps_crypto);
335 DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
336 error = EINVAL;
337 goto bad;
338 }
339 IPCOMPSTAT_INC2(ipcomps_hist, sav->alg_comp);
340
341 clen = crp->crp_olen; /* Length of data after processing */
342
343 /* Release the crypto descriptors */
344 free(xd, M_IPCOMP), xd = NULL;
345 crypto_freereq(crp), crp = NULL;
346
347 /* In case it's not done already, adjust the size of the mbuf chain */
348 m->m_pkthdr.len = clen + hlen + skip;
349
350 if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
351 IPCOMPSTAT_INC(ipcomps_hdrops); /*XXX*/
352 DPRINTF(("%s: m_pullup failed\n", __func__));
353 error = EINVAL; /*XXX*/
354 goto bad;
355 }
356
357 /* Keep the next protocol field */
358 addr = (caddr_t) mtod(m, struct ip *) + skip;
359 nproto = ((struct ipcomp *) addr)->comp_nxt;
360
361 /* Remove the IPCOMP header */
362 error = m_striphdr(m, skip, hlen);
363 if (error) {
364 IPCOMPSTAT_INC(ipcomps_hdrops);
365 DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__,
366 ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
367 (u_long) ntohl(sav->spi)));
368 goto bad;
369 }
370
371 /* Restore the Next Protocol field */
372 m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
373
374 switch (saidx->dst.sa.sa_family) {
375 #ifdef INET6
376 case AF_INET6:
377 error = ipsec6_common_input_cb(m, sav, skip, protoff,
378 &sahtree_tracker);
379 break;
380 #endif
381 #ifdef INET
382 case AF_INET:
383 error = ipsec4_common_input_cb(m, sav, skip, protoff,
384 &sahtree_tracker);
385 break;
386 #endif
387 default:
388 panic("%s: Unexpected address family: %d saidx=%p", __func__,
389 saidx->dst.sa.sa_family, saidx);
390 }
391 CURVNET_RESTORE();
392 return error;
393 bad:
394 ipsec_sahtree_runlock(&sahtree_tracker);
395 CURVNET_RESTORE();
396 if (sav != NULL)
397 key_freesav(&sav);
398 if (m != NULL)
399 m_freem(m);
400 if (xd != NULL)
401 free(xd, M_IPCOMP);
402 if (crp != NULL)
403 crypto_freereq(crp);
404 return error;
405 }
406
407 /*
408 * IPComp output routine, called by ipsec[46]_perform_request()
409 */
410 static int
ipcomp_output(struct mbuf * m,struct secpolicy * sp,struct secasvar * sav,u_int idx,int skip,int protoff)411 ipcomp_output(struct mbuf *m, struct secpolicy *sp, struct secasvar *sav,
412 u_int idx, int skip, int protoff)
413 {
414 IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
415 const struct comp_algo *ipcompx;
416 struct cryptop *crp;
417 struct xform_data *xd;
418 crypto_session_t cryptoid;
419 int error, ralen, maxpacketsize;
420
421 SECASVAR_RLOCK_TRACKER;
422
423 IPSEC_ASSERT(sav != NULL, ("null SA"));
424 ipcompx = sav->tdb_compalgxform;
425 IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
426
427 /*
428 * Do not touch the packet in case our payload to compress
429 * is lower than the minimal threshold of the compression
430 * alogrithm. We will just send out the data uncompressed.
431 * See RFC 3173, 2.2. Non-Expansion Policy.
432 */
433 if (m->m_pkthdr.len <= ipcompx->minlen) {
434 IPCOMPSTAT_INC(ipcomps_threshold);
435 return ipsec_process_done(m, sp, sav, idx);
436 }
437
438 ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
439 IPCOMPSTAT_INC(ipcomps_output);
440
441 /* Check for maximum packet size violations. */
442 switch (sav->sah->saidx.dst.sa.sa_family) {
443 #ifdef INET
444 case AF_INET:
445 maxpacketsize = IP_MAXPACKET;
446 break;
447 #endif /* INET */
448 #ifdef INET6
449 case AF_INET6:
450 maxpacketsize = IPV6_MAXPACKET;
451 break;
452 #endif /* INET6 */
453 default:
454 IPCOMPSTAT_INC(ipcomps_nopf);
455 DPRINTF(("%s: unknown/unsupported protocol family %d, "
456 "IPCA %s/%08lx\n", __func__,
457 sav->sah->saidx.dst.sa.sa_family,
458 ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
459 (u_long) ntohl(sav->spi)));
460 error = EPFNOSUPPORT;
461 goto bad;
462 }
463 if (ralen + skip + IPCOMP_HLENGTH > maxpacketsize) {
464 IPCOMPSTAT_INC(ipcomps_toobig);
465 DPRINTF(("%s: packet in IPCA %s/%08lx got too big "
466 "(len %u, max len %u)\n", __func__,
467 ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
468 (u_long) ntohl(sav->spi),
469 ralen + skip + IPCOMP_HLENGTH, maxpacketsize));
470 error = EMSGSIZE;
471 goto bad;
472 }
473
474 /* Update the counters */
475 IPCOMPSTAT_ADD(ipcomps_obytes, m->m_pkthdr.len - skip);
476
477 m = m_unshare(m, M_NOWAIT);
478 if (m == NULL) {
479 IPCOMPSTAT_INC(ipcomps_hdrops);
480 DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
481 __func__, ipsec_address(&sav->sah->saidx.dst, buf,
482 sizeof(buf)), (u_long) ntohl(sav->spi)));
483 error = ENOBUFS;
484 goto bad;
485 }
486
487 /* Ok now, we can pass to the crypto processing. */
488 SECASVAR_RLOCK(sav);
489 cryptoid = sav->tdb_cryptoid;
490 SECASVAR_RUNLOCK(sav);
491
492 /* Get crypto descriptors */
493 crp = crypto_getreq(cryptoid, M_NOWAIT);
494 if (crp == NULL) {
495 IPCOMPSTAT_INC(ipcomps_crypto);
496 DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
497 error = ENOBUFS;
498 goto bad;
499 }
500
501 /* Compression descriptor */
502 crp->crp_op = CRYPTO_OP_COMPRESS;
503 crp->crp_payload_start = skip;
504 crp->crp_payload_length = ralen;
505
506 /* IPsec-specific opaque crypto info */
507 xd = malloc(sizeof(struct xform_data), M_IPCOMP, M_NOWAIT | M_ZERO);
508 if (xd == NULL) {
509 IPCOMPSTAT_INC(ipcomps_crypto);
510 DPRINTF(("%s: failed to allocate xform_data\n", __func__));
511 crypto_freereq(crp);
512 error = ENOBUFS;
513 goto bad;
514 }
515
516 xd->sp = sp;
517 xd->sav = sav;
518 xd->idx = idx;
519 xd->skip = skip;
520 xd->protoff = protoff;
521 xd->vnet = curvnet;
522 xd->cryptoid = cryptoid;
523
524 /* Crypto operation descriptor */
525 crp->crp_flags = CRYPTO_F_CBIFSYNC;
526 crypto_use_mbuf(crp, m);
527 crp->crp_callback = ipcomp_output_cb;
528 crp->crp_opaque = xd;
529
530 return crypto_dispatch(crp);
531 bad:
532 if (m)
533 m_freem(m);
534 key_freesav(&sav);
535 key_freesp(&sp);
536 return (error);
537 }
538
539 /*
540 * IPComp output callback from the crypto driver.
541 */
542 static int
ipcomp_output_cb(struct cryptop * crp)543 ipcomp_output_cb(struct cryptop *crp)
544 {
545 IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
546 struct xform_data *xd;
547 struct secpolicy *sp;
548 struct secasvar *sav;
549 struct mbuf *m;
550 crypto_session_t cryptoid;
551 u_int idx;
552 int error, skip, protoff;
553
554 m = crp->crp_buf.cb_mbuf;
555 xd = crp->crp_opaque;
556 CURVNET_SET(xd->vnet);
557 idx = xd->idx;
558 sp = xd->sp;
559 sav = xd->sav;
560 skip = xd->skip;
561 protoff = xd->protoff;
562 cryptoid = xd->cryptoid;
563
564 /* Check for crypto errors */
565 if (crp->crp_etype) {
566 if (crp->crp_etype == EAGAIN) {
567 /* Reset the session ID */
568 if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
569 crypto_freesession(cryptoid);
570 xd->cryptoid = crp->crp_session;
571 CURVNET_RESTORE();
572 return (crypto_dispatch(crp));
573 }
574 IPCOMPSTAT_INC(ipcomps_noxform);
575 DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
576 error = crp->crp_etype;
577 goto bad;
578 }
579 /* Shouldn't happen... */
580 if (m == NULL) {
581 IPCOMPSTAT_INC(ipcomps_crypto);
582 DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
583 error = EINVAL;
584 goto bad;
585 }
586 IPCOMPSTAT_INC2(ipcomps_hist, sav->alg_comp);
587
588 if (crp->crp_payload_length > crp->crp_olen) {
589 struct mbuf *mo;
590 struct ipcomp *ipcomp;
591 int roff;
592 uint8_t prot;
593
594 /* Compression helped, inject IPCOMP header. */
595 mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
596 if (mo == NULL) {
597 IPCOMPSTAT_INC(ipcomps_wrap);
598 DPRINTF(("%s: IPCOMP header inject failed "
599 "for IPCA %s/%08lx\n",
600 __func__, ipsec_address(&sav->sah->saidx.dst, buf,
601 sizeof(buf)), (u_long) ntohl(sav->spi)));
602 error = ENOBUFS;
603 goto bad;
604 }
605 ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
606
607 /* Initialize the IPCOMP header */
608 /* XXX alignment always correct? */
609 switch (sav->sah->saidx.dst.sa.sa_family) {
610 #ifdef INET
611 case AF_INET:
612 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
613 break;
614 #endif /* INET */
615 #ifdef INET6
616 case AF_INET6:
617 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
618 break;
619 #endif
620 }
621 ipcomp->comp_flags = 0;
622 ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
623
624 /* Fix Next Protocol in IPv4/IPv6 header */
625 prot = IPPROTO_IPCOMP;
626 m_copyback(m, protoff, sizeof(u_int8_t),
627 (u_char *)&prot);
628
629 /* Adjust the length in the IP header */
630 switch (sav->sah->saidx.dst.sa.sa_family) {
631 #ifdef INET
632 case AF_INET:
633 mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
634 break;
635 #endif /* INET */
636 #ifdef INET6
637 case AF_INET6:
638 mtod(m, struct ip6_hdr *)->ip6_plen =
639 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
640 break;
641 #endif /* INET6 */
642 default:
643 IPCOMPSTAT_INC(ipcomps_nopf);
644 DPRINTF(("%s: unknown/unsupported protocol "
645 "family %d, IPCA %s/%08lx\n", __func__,
646 sav->sah->saidx.dst.sa.sa_family,
647 ipsec_address(&sav->sah->saidx.dst, buf,
648 sizeof(buf)), (u_long) ntohl(sav->spi)));
649 error = EPFNOSUPPORT;
650 goto bad;
651 }
652 } else {
653 /* Compression was useless, we have lost time. */
654 IPCOMPSTAT_INC(ipcomps_uncompr);
655 DPRINTF(("%s: compressions was useless %d <= %d\n",
656 __func__, crp->crp_payload_length, crp->crp_olen));
657 /* XXX remember state to not compress the next couple
658 * of packets, RFC 3173, 2.2. Non-Expansion Policy */
659 }
660
661 /* Release the crypto descriptor */
662 free(xd, M_IPCOMP);
663 crypto_freereq(crp);
664
665 /* NB: m is reclaimed by ipsec_process_done. */
666 error = ipsec_process_done(m, sp, sav, idx);
667 CURVNET_RESTORE();
668 return (error);
669 bad:
670 if (m)
671 m_freem(m);
672 CURVNET_RESTORE();
673 free(xd, M_IPCOMP);
674 crypto_freereq(crp);
675 key_freesav(&sav);
676 key_freesp(&sp);
677 return (error);
678 }
679
680 #ifdef INET
681 static int
ipcomp4_nonexp_encapcheck(const struct mbuf * m,int off,int proto,void * arg __unused)682 ipcomp4_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
683 void *arg __unused)
684 {
685 union sockaddr_union src, dst;
686 const struct ip *ip;
687
688 if (V_ipcomp_enable == 0)
689 return (0);
690 if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
691 return (0);
692 bzero(&src, sizeof(src));
693 bzero(&dst, sizeof(dst));
694 src.sa.sa_family = dst.sa.sa_family = AF_INET;
695 src.sin.sin_len = dst.sin.sin_len = sizeof(struct sockaddr_in);
696 ip = mtod(m, const struct ip *);
697 src.sin.sin_addr = ip->ip_src;
698 dst.sin.sin_addr = ip->ip_dst;
699 return (ipcomp_encapcheck(&src, &dst));
700 }
701
702 static const struct encaptab *ipe4_cookie = NULL;
703 static const struct encap_config ipv4_encap_cfg = {
704 .proto = -1,
705 .min_length = sizeof(struct ip),
706 .exact_match = sizeof(in_addr_t) << 4,
707 .check = ipcomp4_nonexp_encapcheck,
708 .input = ipcomp_nonexp_input
709 };
710 #endif
711 #ifdef INET6
712 static int
ipcomp6_nonexp_encapcheck(const struct mbuf * m,int off,int proto,void * arg __unused)713 ipcomp6_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
714 void *arg __unused)
715 {
716 union sockaddr_union src, dst;
717 const struct ip6_hdr *ip6;
718
719 if (V_ipcomp_enable == 0)
720 return (0);
721 if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
722 return (0);
723 bzero(&src, sizeof(src));
724 bzero(&dst, sizeof(dst));
725 src.sa.sa_family = dst.sa.sa_family = AF_INET;
726 src.sin6.sin6_len = dst.sin6.sin6_len = sizeof(struct sockaddr_in6);
727 ip6 = mtod(m, const struct ip6_hdr *);
728 src.sin6.sin6_addr = ip6->ip6_src;
729 dst.sin6.sin6_addr = ip6->ip6_dst;
730 if (IN6_IS_SCOPE_LINKLOCAL(&src.sin6.sin6_addr)) {
731 /* XXX: sa6_recoverscope() */
732 src.sin6.sin6_scope_id =
733 ntohs(src.sin6.sin6_addr.s6_addr16[1]);
734 src.sin6.sin6_addr.s6_addr16[1] = 0;
735 }
736 if (IN6_IS_SCOPE_LINKLOCAL(&dst.sin6.sin6_addr)) {
737 /* XXX: sa6_recoverscope() */
738 dst.sin6.sin6_scope_id =
739 ntohs(dst.sin6.sin6_addr.s6_addr16[1]);
740 dst.sin6.sin6_addr.s6_addr16[1] = 0;
741 }
742 return (ipcomp_encapcheck(&src, &dst));
743 }
744
745 static const struct encaptab *ipe6_cookie = NULL;
746 static const struct encap_config ipv6_encap_cfg = {
747 .proto = -1,
748 .min_length = sizeof(struct ip6_hdr),
749 .exact_match = sizeof(struct in6_addr) << 4,
750 .check = ipcomp6_nonexp_encapcheck,
751 .input = ipcomp_nonexp_input
752 };
753 #endif
754
755 static struct xformsw ipcomp_xformsw = {
756 .xf_type = XF_IPCOMP,
757 .xf_name = "IPcomp",
758 .xf_init = ipcomp_init,
759 .xf_cleanup = ipcomp_cleanup,
760 .xf_input = ipcomp_input,
761 .xf_output = ipcomp_output,
762 };
763
764 static void
ipcomp_attach(void * dummy __unused)765 ipcomp_attach(void *dummy __unused)
766 {
767
768 #ifdef INET
769 ipe4_cookie = ip_encap_attach(&ipv4_encap_cfg, NULL, M_WAITOK);
770 #endif
771 #ifdef INET6
772 ipe6_cookie = ip6_encap_attach(&ipv6_encap_cfg, NULL, M_WAITOK);
773 #endif
774 xform_attach(&ipcomp_xformsw);
775 }
776
777 static void
ipcomp_detach(void * dummy __unused)778 ipcomp_detach(void *dummy __unused)
779 {
780
781 #ifdef INET
782 ip_encap_detach(ipe4_cookie);
783 #endif
784 #ifdef INET6
785 ip6_encap_detach(ipe6_cookie);
786 #endif
787 xform_detach(&ipcomp_xformsw);
788 }
789
790 SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
791 ipcomp_attach, NULL);
792 SYSUNINIT(ipcomp_xform_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
793 ipcomp_detach, NULL);
794