8a8ab620518468c910f55b1aa267e7d4da45a503
[dragonfly.git] / sys / netproto / ipsec / xform_ipcomp.c
1 /*      $FreeBSD: src/sys/netipsec/xform_ipcomp.c,v 1.1.4.2 2003/02/26 00:14:06 sam Exp $       */
2 /*      $DragonFly: src/sys/netproto/ipsec/xform_ipcomp.c,v 1.10 2006/10/12 01:32:51 hsu Exp $  */
3 /* $OpenBSD: ip_ipcomp.c,v 1.1 2001/07/05 12:08:52 jjbg Exp $ */
4
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
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/mbuf.h>
39 #include <sys/socket.h>
40 #include <sys/kernel.h>
41 #include <sys/protosw.h>
42 #include <sys/sysctl.h>
43 #include <sys/thread2.h>
44
45 #include <netinet/in.h>
46 #include <netinet/in_systm.h>
47 #include <netinet/ip.h>
48 #include <netinet/ip_var.h>
49
50 #include <net/route.h>
51 #include <netproto/ipsec/ipsec.h>
52 #include <netproto/ipsec/xform.h>
53
54 #ifdef INET6
55 #include <netinet/ip6.h>
56 #include <netproto/ipsec/ipsec6.h>
57 #endif
58
59 #include <netproto/ipsec/ipcomp.h>
60 #include <netproto/ipsec/ipcomp_var.h>
61
62 #include <netproto/ipsec/key.h>
63 #include <netproto/ipsec/key_debug.h>
64
65 #include <opencrypto/cryptodev.h>
66 #include <opencrypto/deflate.h>
67 #include <opencrypto/xform.h>
68
69 int     ipcomp_enable = 0;
70 struct  ipcompstat ipcompstat;
71
72 SYSCTL_DECL(_net_inet_ipcomp);
73 SYSCTL_INT(_net_inet_ipcomp, OID_AUTO,
74         ipcomp_enable,  CTLFLAG_RW,     &ipcomp_enable, 0, "");
75 SYSCTL_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS,
76         stats,          CTLFLAG_RD,     &ipcompstat,    ipcompstat, "");
77
78 static int ipcomp_input_cb(struct cryptop *crp);
79 static int ipcomp_output_cb(struct cryptop *crp);
80
81 struct comp_algo *
82 ipcomp_algorithm_lookup(int alg)
83 {
84         if (alg >= IPCOMP_ALG_MAX)
85                 return NULL;
86         switch (alg) {
87         case SADB_X_CALG_DEFLATE:
88                 return &comp_algo_deflate;
89         }
90         return NULL;
91 }
92
93 /*
94  * ipcomp_init() is called when an CPI is being set up.
95  */
96 static int
97 ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
98 {
99         struct comp_algo *tcomp;
100         struct cryptoini cric;
101
102         /* NB: algorithm really comes in alg_enc and not alg_comp! */
103         tcomp = ipcomp_algorithm_lookup(sav->alg_enc);
104         if (tcomp == NULL) {
105                 DPRINTF(("ipcomp_init: unsupported compression algorithm %d\n",
106                          sav->alg_comp));
107                 return EINVAL;
108         }
109         sav->alg_comp = sav->alg_enc;           /* set for doing histogram */
110         sav->tdb_xform = xsp;
111         sav->tdb_compalgxform = tcomp;
112
113         /* Initialize crypto session */
114         bzero(&cric, sizeof (cric));
115         cric.cri_alg = sav->tdb_compalgxform->type;
116
117         return crypto_newsession(&sav->tdb_cryptoid, &cric, crypto_support);
118 }
119
120 /*
121  * ipcomp_zeroize() used when IPCA is deleted
122  */
123 static int
124 ipcomp_zeroize(struct secasvar *sav)
125 {
126         int err;
127
128         err = crypto_freesession(sav->tdb_cryptoid);
129         sav->tdb_cryptoid = 0;
130         return err;
131 }
132
133 /*
134  * ipcomp_input() gets called to uncompress an input packet
135  */
136 static int
137 ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
138 {
139         struct tdb_crypto *tc;
140         struct cryptodesc *crdc;
141         struct cryptop *crp;
142         int hlen = IPCOMP_HLENGTH;
143
144         /* Get crypto descriptors */
145         crp = crypto_getreq(1);
146         if (crp == NULL) {
147                 m_freem(m);
148                 DPRINTF(("ipcomp_input: no crypto descriptors\n"));
149                 ipcompstat.ipcomps_crypto++;
150                 return ENOBUFS;
151         }
152         /* Get IPsec-specific opaque pointer */
153         tc = kmalloc(sizeof (*tc), M_XDATA, 
154                     M_INTWAIT | M_ZERO | M_NULLOK);
155         if (tc == NULL) {
156                 m_freem(m);
157                 crypto_freereq(crp);
158                 DPRINTF(("ipcomp_input: cannot allocate tdb_crypto\n"));
159                 ipcompstat.ipcomps_crypto++;
160                 return ENOBUFS;
161         }
162         crdc = crp->crp_desc;
163
164         crdc->crd_skip = skip + hlen;
165         crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
166         crdc->crd_inject = skip;
167
168         tc->tc_ptr = 0;
169
170         /* Decompression operation */
171         crdc->crd_alg = sav->tdb_compalgxform->type;
172
173         /* Crypto operation descriptor */
174         crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
175         crp->crp_flags = CRYPTO_F_IMBUF;
176         crp->crp_buf = (caddr_t) m;
177         crp->crp_callback = ipcomp_input_cb;
178         crp->crp_sid = sav->tdb_cryptoid;
179         crp->crp_opaque = (caddr_t) tc;
180
181         /* These are passed as-is to the callback */
182         tc->tc_spi = sav->spi;
183         tc->tc_dst = sav->sah->saidx.dst;
184         tc->tc_proto = sav->sah->saidx.proto;
185         tc->tc_protoff = protoff;
186         tc->tc_skip = skip;
187
188         return crypto_dispatch(crp);
189 }
190
191 #ifdef INET6
192 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do {              \
193         if (saidx->dst.sa.sa_family == AF_INET6) {                           \
194                 error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \
195         } else {                                                             \
196                 error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \
197         }                                                                    \
198 } while (0)
199 #else
200 #define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag)                   \
201         (error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag))
202 #endif
203
204 /*
205  * IPComp input callback from the crypto driver.
206  */
207 static int
208 ipcomp_input_cb(struct cryptop *crp)
209 {
210         struct cryptodesc *crd;
211         struct tdb_crypto *tc;
212         int skip, protoff;
213         struct mtag *mtag;
214         struct mbuf *m;
215         struct secasvar *sav;
216         struct secasindex *saidx;
217         int hlen = IPCOMP_HLENGTH, error, clen;
218         u_int8_t nproto;
219         caddr_t addr;
220
221         crd = crp->crp_desc;
222
223         tc = (struct tdb_crypto *) crp->crp_opaque;
224         KASSERT(tc != NULL, ("ipcomp_input_cb: null opaque crypto data area!"));
225         skip = tc->tc_skip;
226         protoff = tc->tc_protoff;
227         mtag = (struct mtag *) tc->tc_ptr;
228         m = (struct mbuf *) crp->crp_buf;
229
230         crit_enter();
231
232         sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
233         if (sav == NULL) {
234                 ipcompstat.ipcomps_notdb++;
235                 DPRINTF(("ipcomp_input_cb: SA expired while in crypto\n"));
236                 error = ENOBUFS;                /*XXX*/
237                 goto bad;
238         }
239
240         saidx = &sav->sah->saidx;
241         KASSERT(saidx->dst.sa.sa_family == AF_INET ||
242                 saidx->dst.sa.sa_family == AF_INET6,
243                 ("ah_input_cb: unexpected protocol family %u",
244                  saidx->dst.sa.sa_family));
245
246         /* Check for crypto errors */
247         if (crp->crp_etype) {
248                 /* Reset the session ID */
249                 if (sav->tdb_cryptoid != 0)
250                         sav->tdb_cryptoid = crp->crp_sid;
251
252                 if (crp->crp_etype == EAGAIN) {
253                         KEY_FREESAV(&sav);
254                         crit_exit();
255                         return crypto_dispatch(crp);
256                 }
257
258                 ipcompstat.ipcomps_noxform++;
259                 DPRINTF(("ipcomp_input_cb: crypto error %d\n", crp->crp_etype));
260                 error = crp->crp_etype;
261                 goto bad;
262         }
263         /* Shouldn't happen... */
264         if (m == NULL) {
265                 ipcompstat.ipcomps_crypto++;
266                 DPRINTF(("ipcomp_input_cb: null mbuf returned from crypto\n"));
267                 error = EINVAL;
268                 goto bad;
269         }
270         ipcompstat.ipcomps_hist[sav->alg_comp]++;
271
272         clen = crp->crp_olen;           /* Length of data after processing */
273
274         /* Release the crypto descriptors */
275         kfree(tc, M_XDATA), tc = NULL;
276         crypto_freereq(crp), crp = NULL;
277
278         /* In case it's not done already, adjust the size of the mbuf chain */
279         m->m_pkthdr.len = clen + hlen + skip;
280
281         if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) {
282                 ipcompstat.ipcomps_hdrops++;            /*XXX*/
283                 DPRINTF(("ipcomp_input_cb: m_pullup failed\n"));
284                 error = EINVAL;                         /*XXX*/
285                 goto bad;
286         }
287
288         /* Keep the next protocol field */
289         addr = (caddr_t) mtod(m, struct ip *) + skip;
290         nproto = ((struct ipcomp *) addr)->comp_nxt;
291
292         /* Remove the IPCOMP header */
293         error = m_striphdr(m, skip, hlen);
294         if (error) {
295                 ipcompstat.ipcomps_hdrops++;
296                 DPRINTF(("ipcomp_input_cb: bad mbuf chain, IPCA %s/%08lx\n",
297                          ipsec_address(&sav->sah->saidx.dst),
298                          (u_long) ntohl(sav->spi)));
299                 goto bad;
300         }
301
302         /* Restore the Next Protocol field */
303         m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
304
305         IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, NULL);
306
307         KEY_FREESAV(&sav);
308         crit_exit();
309         return error;
310 bad:
311         if (sav)
312                 KEY_FREESAV(&sav);
313         crit_exit();
314         if (m)
315                 m_freem(m);
316         if (tc != NULL)
317                 kfree(tc, M_XDATA);
318         if (crp)
319                 crypto_freereq(crp);
320         return error;
321 }
322
323 /*
324  * IPComp output routine, called by ipsec[46]_process_packet()
325  */
326 static int
327 ipcomp_output(
328         struct mbuf *m,
329         struct ipsecrequest *isr,
330         struct mbuf **mp,
331         int skip,
332         int protoff
333 )
334 {
335         struct secasvar *sav;
336         struct comp_algo *ipcompx;
337         int error, ralen, hlen, maxpacketsize, roff;
338         u_int8_t prot;
339         struct cryptodesc *crdc;
340         struct cryptop *crp;
341         struct tdb_crypto *tc;
342         struct mbuf *mo;
343         struct ipcomp *ipcomp;
344
345         sav = isr->sav;
346         KASSERT(sav != NULL, ("ipcomp_output: null SA"));
347         ipcompx = sav->tdb_compalgxform;
348         KASSERT(ipcompx != NULL, ("ipcomp_output: null compression xform"));
349
350         ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
351         hlen = IPCOMP_HLENGTH;
352
353         ipcompstat.ipcomps_output++;
354
355         /* Check for maximum packet size violations. */
356         switch (sav->sah->saidx.dst.sa.sa_family) {
357 #ifdef INET
358         case AF_INET:
359                 maxpacketsize =  IP_MAXPACKET;
360                 break;
361 #endif /* INET */
362 #ifdef INET6
363         case AF_INET6:
364                 maxpacketsize =  IPV6_MAXPACKET;
365                 break;
366 #endif /* INET6 */
367         default:
368                 ipcompstat.ipcomps_nopf++;
369                 DPRINTF(("ipcomp_output: unknown/unsupported protocol family %d"
370                     ", IPCA %s/%08lx\n", 
371                     sav->sah->saidx.dst.sa.sa_family,
372                     ipsec_address(&sav->sah->saidx.dst),
373                     (u_long) ntohl(sav->spi)));
374                 error = EPFNOSUPPORT;
375                 goto bad;
376         }
377         if (skip + hlen + ralen > maxpacketsize) {
378                 ipcompstat.ipcomps_toobig++;
379                 DPRINTF(("ipcomp_output: packet in IPCA %s/%08lx got too big "
380                     "(len %u, max len %u)\n",
381                     ipsec_address(&sav->sah->saidx.dst),
382                     (u_long) ntohl(sav->spi),
383                     skip + hlen + ralen, maxpacketsize));
384                 error = EMSGSIZE;
385                 goto bad;
386         }
387
388         /* Update the counters */
389         ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip;
390
391         m = m_clone(m);
392         if (m == NULL) {
393                 ipcompstat.ipcomps_hdrops++;
394                 DPRINTF(("ipcomp_output: cannot clone mbuf chain, IPCA %s/%08lx\n", 
395                     ipsec_address(&sav->sah->saidx.dst),
396                     (u_long) ntohl(sav->spi)));
397                 error = ENOBUFS;
398                 goto bad;
399         }
400
401         /* Inject IPCOMP header */
402         mo = m_makespace(m, skip, hlen, &roff);
403         if (mo == NULL) {
404                 ipcompstat.ipcomps_wrap++;
405                 DPRINTF(("ipcomp_output: failed to inject IPCOMP header for "
406                     "IPCA %s/%08lx\n",
407                     ipsec_address(&sav->sah->saidx.dst),
408                     (u_long) ntohl(sav->spi)));
409                 error = ENOBUFS;
410                 goto bad;
411         }
412         ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + roff);
413
414         /* Initialize the IPCOMP header */
415         /* XXX alignment always correct? */
416         switch (sav->sah->saidx.dst.sa.sa_family) {
417 #ifdef INET
418         case AF_INET:
419                 ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
420                 break;
421 #endif /* INET */
422 #ifdef INET6
423         case AF_INET6:
424                 ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
425                 break;
426 #endif
427         }
428         ipcomp->comp_flags = 0;
429         ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
430
431         /* Fix Next Protocol in IPv4/IPv6 header */
432         prot = IPPROTO_IPCOMP;
433         m_copyback(m, protoff, sizeof(u_int8_t), (u_char *) &prot);
434
435         /* Ok now, we can pass to the crypto processing */
436
437         /* Get crypto descriptors */
438         crp = crypto_getreq(1);
439         if (crp == NULL) {
440                 ipcompstat.ipcomps_crypto++;
441                 DPRINTF(("ipcomp_output: failed to acquire crypto descriptor\n"));
442                 error = ENOBUFS;
443                 goto bad;
444         }
445         crdc = crp->crp_desc;
446
447         /* Compression descriptor */
448         crdc->crd_skip = skip + hlen;
449         crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
450         crdc->crd_flags = CRD_F_COMP;
451         crdc->crd_inject = skip + hlen;
452
453         /* Compression operation */
454         crdc->crd_alg = ipcompx->type;
455
456         /* IPsec-specific opaque crypto info */
457         tc = kmalloc(sizeof(struct tdb_crypto),
458                     M_XDATA, M_INTWAIT | M_ZERO | M_NULLOK);
459         if (tc == NULL) {
460                 ipcompstat.ipcomps_crypto++;
461                 DPRINTF(("ipcomp_output: failed to allocate tdb_crypto\n"));
462                 crypto_freereq(crp);
463                 error = ENOBUFS;
464                 goto bad;
465         }
466
467         tc->tc_isr = isr;
468         tc->tc_spi = sav->spi;
469         tc->tc_dst = sav->sah->saidx.dst;
470         tc->tc_proto = sav->sah->saidx.proto;
471         tc->tc_skip = skip + hlen;
472
473         /* Crypto operation descriptor */
474         crp->crp_ilen = m->m_pkthdr.len;        /* Total input length */
475         crp->crp_flags = CRYPTO_F_IMBUF;
476         crp->crp_buf = (caddr_t) m;
477         crp->crp_callback = ipcomp_output_cb;
478         crp->crp_opaque = (caddr_t) tc;
479         crp->crp_sid = sav->tdb_cryptoid;
480
481         return crypto_dispatch(crp);
482 bad:
483         if (m)
484                 m_freem(m);
485         return (error);
486 }
487
488 /*
489  * IPComp output callback from the crypto driver.
490  */
491 static int
492 ipcomp_output_cb(struct cryptop *crp)
493 {
494         struct tdb_crypto *tc;
495         struct ipsecrequest *isr;
496         struct secasvar *sav;
497         struct mbuf *m;
498         int error, skip, rlen;
499
500         tc = (struct tdb_crypto *) crp->crp_opaque;
501         KASSERT(tc != NULL, ("ipcomp_output_cb: null opaque data area!"));
502         m = (struct mbuf *) crp->crp_buf;
503         skip = tc->tc_skip;
504         rlen = crp->crp_ilen - skip;
505
506         crit_enter();
507
508         isr = tc->tc_isr;
509         sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi);
510         if (sav == NULL) {
511                 ipcompstat.ipcomps_notdb++;
512                 DPRINTF(("ipcomp_output_cb: SA expired while in crypto\n"));
513                 error = ENOBUFS;                /*XXX*/
514                 goto bad;
515         }
516         KASSERT(isr->sav == sav, ("ipcomp_output_cb: SA changed\n"));
517
518         /* Check for crypto errors */
519         if (crp->crp_etype) {
520                 /* Reset session ID */
521                 if (sav->tdb_cryptoid != 0)
522                         sav->tdb_cryptoid = crp->crp_sid;
523
524                 if (crp->crp_etype == EAGAIN) {
525                         KEY_FREESAV(&sav);
526                         crit_exit();
527                         return crypto_dispatch(crp);
528                 }
529                 ipcompstat.ipcomps_noxform++;
530                 DPRINTF(("ipcomp_output_cb: crypto error %d\n", crp->crp_etype));
531                 error = crp->crp_etype;
532                 goto bad;
533         }
534         /* Shouldn't happen... */
535         if (m == NULL) {
536                 ipcompstat.ipcomps_crypto++;
537                 DPRINTF(("ipcomp_output_cb: bogus return buffer from crypto\n"));
538                 error = EINVAL;
539                 goto bad;
540         }
541         ipcompstat.ipcomps_hist[sav->alg_comp]++;
542
543         if (rlen > crp->crp_olen) {
544                 /* Adjust the length in the IP header */
545                 switch (sav->sah->saidx.dst.sa.sa_family) {
546 #ifdef INET
547                 case AF_INET:
548                         mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
549                         break;
550 #endif /* INET */
551 #ifdef INET6
552                 case AF_INET6:
553                         mtod(m, struct ip6_hdr *)->ip6_plen =
554                                 htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
555                         break;
556 #endif /* INET6 */
557                 default:
558                         ipcompstat.ipcomps_nopf++;
559                         DPRINTF(("ipcomp_output: unknown/unsupported protocol "
560                             "family %d, IPCA %s/%08lx\n", 
561                             sav->sah->saidx.dst.sa.sa_family,
562                             ipsec_address(&sav->sah->saidx.dst), 
563                             (u_long) ntohl(sav->spi)));
564                         error = EPFNOSUPPORT;
565                         goto bad;
566                 }
567         } else {
568                 /* compression was useless, we have lost time */
569                 /* XXX add statistic */
570         }
571
572         /* Release the crypto descriptor */
573         kfree(tc, M_XDATA);
574         crypto_freereq(crp);
575
576         /* NB: m is reclaimed by ipsec_process_done. */
577         error = ipsec_process_done(m, isr);
578         KEY_FREESAV(&sav);
579         crit_exit();
580         return error;
581 bad:
582         if (sav)
583                 KEY_FREESAV(&sav);
584         crit_exit();
585         if (m)
586                 m_freem(m);
587         kfree(tc, M_XDATA);
588         crypto_freereq(crp);
589         return error;
590 }
591
592 static struct xformsw ipcomp_xformsw = {
593         XF_IPCOMP,              XFT_COMP,               "IPcomp",
594         ipcomp_init,            ipcomp_zeroize,         ipcomp_input,
595         ipcomp_output
596 };
597
598 static void
599 ipcomp_attach(void)
600 {
601         xform_register(&ipcomp_xformsw);
602 }
603 SYSINIT(ipcomp_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, ipcomp_attach, NULL)