FreeBSD/Linux Kernel Cross Reference
sys/netipsec/ipsec.c
1 /* $FreeBSD: releng/8.1/sys/netipsec/ipsec.c 207695 2010-05-06 06:44:19Z bz $ */
2 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */
3
4 /*-
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
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 * 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. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 /*
34 * IPsec controller part.
35 */
36
37 #include "opt_inet.h"
38 #include "opt_inet6.h"
39 #include "opt_ipsec.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/malloc.h>
44 #include <sys/mbuf.h>
45 #include <sys/domain.h>
46 #include <sys/priv.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/errno.h>
51 #include <sys/time.h>
52 #include <sys/kernel.h>
53 #include <sys/syslog.h>
54 #include <sys/sysctl.h>
55 #include <sys/proc.h>
56
57 #include <net/if.h>
58 #include <net/route.h>
59 #include <net/vnet.h>
60
61 #include <netinet/in.h>
62 #include <netinet/in_systm.h>
63 #include <netinet/ip.h>
64 #include <netinet/ip_var.h>
65 #include <netinet/in_var.h>
66 #include <netinet/udp.h>
67 #include <netinet/udp_var.h>
68 #include <netinet/tcp.h>
69 #include <netinet/udp.h>
70
71 #include <netinet/ip6.h>
72 #ifdef INET6
73 #include <netinet6/ip6_var.h>
74 #endif
75 #include <netinet/in_pcb.h>
76 #ifdef INET6
77 #include <netinet/icmp6.h>
78 #endif
79
80 #include <sys/types.h>
81 #include <netipsec/ipsec.h>
82 #ifdef INET6
83 #include <netipsec/ipsec6.h>
84 #endif
85 #include <netipsec/ah_var.h>
86 #include <netipsec/esp_var.h>
87 #include <netipsec/ipcomp.h> /*XXX*/
88 #include <netipsec/ipcomp_var.h>
89
90 #include <netipsec/key.h>
91 #include <netipsec/keydb.h>
92 #include <netipsec/key_debug.h>
93
94 #include <netipsec/xform.h>
95
96 #include <machine/in_cksum.h>
97
98 #include <opencrypto/cryptodev.h>
99
100 #ifdef IPSEC_DEBUG
101 VNET_DEFINE(int, ipsec_debug) = 1;
102 #else
103 VNET_DEFINE(int, ipsec_debug) = 0;
104 #endif
105
106 /* NB: name changed so netstat doesn't use it. */
107 VNET_DEFINE(struct ipsecstat, ipsec4stat);
108 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */
109 /* DF bit on encap. 0: clear 1: set 2: copy */
110 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0;
111 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE;
112 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE;
113 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE;
114 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE;
115 VNET_DEFINE(struct secpolicy, ip4_def_policy);
116 /* ECN ignore(-1)/forbidden(0)/allowed(1) */
117 VNET_DEFINE(int, ip4_ipsec_ecn) = 0;
118 VNET_DEFINE(int, ip4_esp_randpad) = -1;
119
120 /*
121 * Crypto support requirements:
122 *
123 * 1 require hardware support
124 * -1 require software support
125 * 0 take anything
126 */
127 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE;
128
129 SYSCTL_DECL(_net_inet_ipsec);
130
131 /* net.inet.ipsec */
132 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy,
133 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0,
134 "IPsec default policy.");
135 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
136 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0,
137 "Default ESP transport mode level");
138 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
139 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0,
140 "Default ESP tunnel mode level.");
141 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
142 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0,
143 "AH transfer mode default level.");
144 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
145 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0,
146 "AH tunnel mode default level.");
147 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos,
148 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0,
149 "If set clear type-of-service field when doing AH computation.");
150 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask,
151 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0,
152 "If not set clear offset field mask when doing AH computation.");
153 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit,
154 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0,
155 "Do not fragment bit on encap.");
156 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn,
157 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0,
158 "Explicit Congestion Notification handling.");
159 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug,
160 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0,
161 "Enable IPsec debugging output when set.");
162 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support,
163 CTLFLAG_RW, &VNET_NAME(crypto_support), 0,
164 "Crypto driver selection.");
165 SYSCTL_VNET_STRUCT(_net_inet_ipsec, OID_AUTO, ipsecstats,
166 CTLFLAG_RD, &VNET_NAME(ipsec4stat), ipsecstat,
167 "IPsec IPv4 statistics.");
168
169 #ifdef REGRESSION
170 /*
171 * When set to 1, IPsec will send packets with the same sequence number.
172 * This allows to verify if the other side has proper replay attacks detection.
173 */
174 VNET_DEFINE(int, ipsec_replay) = 0;
175 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay,
176 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0,
177 "Emulate replay attack");
178 /*
179 * When set 1, IPsec will send packets with corrupted HMAC.
180 * This allows to verify if the other side properly detects modified packets.
181 */
182 VNET_DEFINE(int, ipsec_integrity) = 0;
183 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity,
184 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0,
185 "Emulate man-in-the-middle attack");
186 #endif
187
188 #ifdef INET6
189 VNET_DEFINE(struct ipsecstat, ipsec6stat);
190 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE;
191 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE;
192 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE;
193 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE;
194 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */
195
196 SYSCTL_DECL(_net_inet6_ipsec6);
197
198 /* net.inet6.ipsec6 */
199 #ifdef COMPAT_KAME
200 SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD,
201 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics.");
202 #endif /* COMPAT_KAME */
203 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW,
204 &VNET_NAME(ip4_def_policy).policy, 0,
205 "IPsec default policy.");
206 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV,
207 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0,
208 "Default ESP transport mode level.");
209 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV,
210 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0,
211 "Default ESP tunnel mode level.");
212 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV,
213 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0,
214 "AH transfer mode default level.");
215 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV,
216 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0,
217 "AH tunnel mode default level.");
218 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN,
219 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0,
220 "Explicit Congestion Notification handling.");
221 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW,
222 &VNET_NAME(ipsec_debug), 0,
223 "Enable IPsec debugging output when set.");
224 SYSCTL_VNET_STRUCT(_net_inet6_ipsec6, IPSECCTL_STATS,
225 ipsecstats, CTLFLAG_RD, &VNET_NAME(ipsec6stat), ipsecstat,
226 "IPsec IPv6 statistics.");
227 #endif /* INET6 */
228
229 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *));
230 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int));
231 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int));
232 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *));
233 #ifdef INET6
234 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int));
235 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *));
236 #endif
237 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *));
238 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src));
239 static void vshiftl __P((unsigned char *, int, int));
240
241 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy");
242
243 /*
244 * Return a held reference to the default SP.
245 */
246 static struct secpolicy *
247 key_allocsp_default(const char* where, int tag)
248 {
249 struct secpolicy *sp;
250
251 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
252 printf("DP key_allocsp_default from %s:%u\n", where, tag));
253
254 sp = &V_ip4_def_policy;
255 if (sp->policy != IPSEC_POLICY_DISCARD &&
256 sp->policy != IPSEC_POLICY_NONE) {
257 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n",
258 sp->policy, IPSEC_POLICY_NONE));
259 sp->policy = IPSEC_POLICY_NONE;
260 }
261 key_addref(sp);
262
263 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
264 printf("DP key_allocsp_default returns SP:%p (%u)\n",
265 sp, sp->refcnt));
266 return (sp);
267 }
268 #define KEY_ALLOCSP_DEFAULT() \
269 key_allocsp_default(__FILE__, __LINE__)
270
271 /*
272 * For OUTBOUND packet having a socket. Searching SPD for packet,
273 * and return a pointer to SP.
274 * OUT: NULL: no apropreate SP found, the following value is set to error.
275 * 0 : bypass
276 * EACCES : discard packet.
277 * ENOENT : ipsec_acquire() in progress, maybe.
278 * others : error occured.
279 * others: a pointer to SP
280 *
281 * NOTE: IPv6 mapped adddress concern is implemented here.
282 */
283 struct secpolicy *
284 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir)
285 {
286 struct secpolicy *sp;
287
288 IPSEC_ASSERT(tdbi != NULL, ("null tdbi"));
289 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
290 ("invalid direction %u", dir));
291
292 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir);
293 if (sp == NULL) /*XXX????*/
294 sp = KEY_ALLOCSP_DEFAULT();
295 IPSEC_ASSERT(sp != NULL, ("null SP"));
296 return (sp);
297 }
298
299 /*
300 * For OUTBOUND packet having a socket. Searching SPD for packet,
301 * and return a pointer to SP.
302 * OUT: NULL: no apropreate SP found, the following value is set to error.
303 * 0 : bypass
304 * EACCES : discard packet.
305 * ENOENT : ipsec_acquire() in progress, maybe.
306 * others : error occured.
307 * others: a pointer to SP
308 *
309 * NOTE: IPv6 mapped adddress concern is implemented here.
310 */
311 static struct secpolicy *
312 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error)
313 {
314 struct inpcbpolicy *pcbsp;
315 struct secpolicy *currsp = NULL; /* Policy on socket. */
316 struct secpolicy *sp;
317
318 IPSEC_ASSERT(m != NULL, ("null mbuf"));
319 IPSEC_ASSERT(inp != NULL, ("null inpcb"));
320 IPSEC_ASSERT(error != NULL, ("null error"));
321 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
322 ("invalid direction %u", dir));
323
324 /* Set spidx in pcb. */
325 *error = ipsec_setspidx_inpcb(m, inp);
326 if (*error)
327 return (NULL);
328
329 pcbsp = inp->inp_sp;
330 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp"));
331 switch (dir) {
332 case IPSEC_DIR_INBOUND:
333 currsp = pcbsp->sp_in;
334 break;
335 case IPSEC_DIR_OUTBOUND:
336 currsp = pcbsp->sp_out;
337 break;
338 }
339 IPSEC_ASSERT(currsp != NULL, ("null currsp"));
340
341 if (pcbsp->priv) { /* When privilieged socket. */
342 switch (currsp->policy) {
343 case IPSEC_POLICY_BYPASS:
344 case IPSEC_POLICY_IPSEC:
345 key_addref(currsp);
346 sp = currsp;
347 break;
348
349 case IPSEC_POLICY_ENTRUST:
350 /* Look for a policy in SPD. */
351 sp = KEY_ALLOCSP(&currsp->spidx, dir);
352 if (sp == NULL) /* No SP found. */
353 sp = KEY_ALLOCSP_DEFAULT();
354 break;
355
356 default:
357 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n",
358 __func__, currsp->policy));
359 *error = EINVAL;
360 return (NULL);
361 }
362 } else { /* Unpriv, SPD has policy. */
363 sp = KEY_ALLOCSP(&currsp->spidx, dir);
364 if (sp == NULL) { /* No SP found. */
365 switch (currsp->policy) {
366 case IPSEC_POLICY_BYPASS:
367 ipseclog((LOG_ERR, "%s: Illegal policy for "
368 "non-priviliged defined %d\n",
369 __func__, currsp->policy));
370 *error = EINVAL;
371 return (NULL);
372
373 case IPSEC_POLICY_ENTRUST:
374 sp = KEY_ALLOCSP_DEFAULT();
375 break;
376
377 case IPSEC_POLICY_IPSEC:
378 key_addref(currsp);
379 sp = currsp;
380 break;
381
382 default:
383 ipseclog((LOG_ERR, "%s: Invalid policy for "
384 "PCB %d\n", __func__, currsp->policy));
385 *error = EINVAL;
386 return (NULL);
387 }
388 }
389 }
390 IPSEC_ASSERT(sp != NULL,
391 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy));
392 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
393 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n",
394 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt));
395 return (sp);
396 }
397
398 /*
399 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet,
400 * and return a pointer to SP.
401 * OUT: positive: a pointer to the entry for security policy leaf matched.
402 * NULL: no apropreate SP found, the following value is set to error.
403 * 0 : bypass
404 * EACCES : discard packet.
405 * ENOENT : ipsec_acquire() in progress, maybe.
406 * others : error occured.
407 */
408 struct secpolicy *
409 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error)
410 {
411 struct secpolicyindex spidx;
412 struct secpolicy *sp;
413
414 IPSEC_ASSERT(m != NULL, ("null mbuf"));
415 IPSEC_ASSERT(error != NULL, ("null error"));
416 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
417 ("invalid direction %u", dir));
418
419 sp = NULL;
420 if (key_havesp(dir)) {
421 /* Make an index to look for a policy. */
422 *error = ipsec_setspidx(m, &spidx,
423 (flag & IP_FORWARDING) ? 0 : 1);
424 if (*error != 0) {
425 DPRINTF(("%s: setpidx failed, dir %u flag %u\n",
426 __func__, dir, flag));
427 return (NULL);
428 }
429 spidx.dir = dir;
430
431 sp = KEY_ALLOCSP(&spidx, dir);
432 }
433 if (sp == NULL) /* No SP found, use system default. */
434 sp = KEY_ALLOCSP_DEFAULT();
435 IPSEC_ASSERT(sp != NULL, ("null SP"));
436 return (sp);
437 }
438
439 struct secpolicy *
440 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error,
441 struct inpcb *inp)
442 {
443 struct secpolicy *sp;
444
445 *error = 0;
446 if (inp == NULL)
447 sp = ipsec_getpolicybyaddr(m, dir, flag, error);
448 else
449 sp = ipsec_getpolicybysock(m, dir, inp, error);
450 if (sp == NULL) {
451 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error"));
452 V_ipsec4stat.ips_out_inval++;
453 return (NULL);
454 }
455 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error));
456 switch (sp->policy) {
457 case IPSEC_POLICY_ENTRUST:
458 default:
459 printf("%s: invalid policy %u\n", __func__, sp->policy);
460 /* FALLTHROUGH */
461 case IPSEC_POLICY_DISCARD:
462 V_ipsec4stat.ips_out_polvio++;
463 *error = -EINVAL; /* Packet is discarded by caller. */
464 break;
465 case IPSEC_POLICY_BYPASS:
466 case IPSEC_POLICY_NONE:
467 KEY_FREESP(&sp);
468 sp = NULL; /* NB: force NULL result. */
469 break;
470 case IPSEC_POLICY_IPSEC:
471 if (sp->req == NULL) /* Acquire a SA. */
472 *error = key_spdacquire(sp);
473 break;
474 }
475 if (*error != 0) {
476 KEY_FREESP(&sp);
477 sp = NULL;
478 }
479 return (sp);
480 }
481
482 static int
483 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp)
484 {
485 int error;
486
487 IPSEC_ASSERT(inp != NULL, ("null inp"));
488 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
489 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL,
490 ("null sp_in || sp_out"));
491
492 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1);
493 if (error == 0) {
494 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND;
495 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx;
496 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND;
497 } else {
498 bzero(&inp->inp_sp->sp_in->spidx,
499 sizeof (inp->inp_sp->sp_in->spidx));
500 bzero(&inp->inp_sp->sp_out->spidx,
501 sizeof (inp->inp_sp->sp_in->spidx));
502 }
503 return (error);
504 }
505
506 /*
507 * Configure security policy index (src/dst/proto/sport/dport)
508 * by looking at the content of mbuf.
509 * The caller is responsible for error recovery (like clearing up spidx).
510 */
511 static int
512 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport)
513 {
514 struct ip *ip = NULL;
515 struct ip ipbuf;
516 u_int v;
517 struct mbuf *n;
518 int len;
519 int error;
520
521 IPSEC_ASSERT(m != NULL, ("null mbuf"));
522
523 /*
524 * Validate m->m_pkthdr.len. We see incorrect length if we
525 * mistakenly call this function with inconsistent mbuf chain
526 * (like 4.4BSD tcp/udp processing). XXX Should we panic here?
527 */
528 len = 0;
529 for (n = m; n; n = n->m_next)
530 len += n->m_len;
531 if (m->m_pkthdr.len != len) {
532 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
533 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n",
534 __func__, len, m->m_pkthdr.len));
535 return (EINVAL);
536 }
537
538 if (m->m_pkthdr.len < sizeof(struct ip)) {
539 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
540 printf("%s: pkthdr len(%d) too small (v4), ignored.\n",
541 __func__, m->m_pkthdr.len));
542 return (EINVAL);
543 }
544
545 if (m->m_len >= sizeof(*ip))
546 ip = mtod(m, struct ip *);
547 else {
548 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf);
549 ip = &ipbuf;
550 }
551 #ifdef _IP_VHL
552 v = _IP_VHL_V(ip->ip_vhl);
553 #else
554 v = ip->ip_v;
555 #endif
556 switch (v) {
557 case 4:
558 error = ipsec4_setspidx_ipaddr(m, spidx);
559 if (error)
560 return (error);
561 ipsec4_get_ulp(m, spidx, needport);
562 return (0);
563 #ifdef INET6
564 case 6:
565 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) {
566 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
567 printf("%s: pkthdr len(%d) too small (v6), "
568 "ignored\n", __func__, m->m_pkthdr.len));
569 return (EINVAL);
570 }
571 error = ipsec6_setspidx_ipaddr(m, spidx);
572 if (error)
573 return (error);
574 ipsec6_get_ulp(m, spidx, needport);
575 return (0);
576 #endif
577 default:
578 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
579 printf("%s: " "unknown IP version %u, ignored.\n",
580 __func__, v));
581 return (EINVAL);
582 }
583 }
584
585 static void
586 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
587 {
588 u_int8_t nxt;
589 int off;
590
591 /* Sanity check. */
592 IPSEC_ASSERT(m != NULL, ("null mbuf"));
593 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short"));
594
595 /* NB: ip_input() flips it into host endian. XXX Need more checking. */
596 if (m->m_len < sizeof (struct ip)) {
597 struct ip *ip = mtod(m, struct ip *);
598 if (ip->ip_off & (IP_MF | IP_OFFMASK))
599 goto done;
600 #ifdef _IP_VHL
601 off = _IP_VHL_HL(ip->ip_vhl) << 2;
602 #else
603 off = ip->ip_hl << 2;
604 #endif
605 nxt = ip->ip_p;
606 } else {
607 struct ip ih;
608
609 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih);
610 if (ih.ip_off & (IP_MF | IP_OFFMASK))
611 goto done;
612 #ifdef _IP_VHL
613 off = _IP_VHL_HL(ih.ip_vhl) << 2;
614 #else
615 off = ih.ip_hl << 2;
616 #endif
617 nxt = ih.ip_p;
618 }
619
620 while (off < m->m_pkthdr.len) {
621 struct ip6_ext ip6e;
622 struct tcphdr th;
623 struct udphdr uh;
624
625 switch (nxt) {
626 case IPPROTO_TCP:
627 spidx->ul_proto = nxt;
628 if (!needport)
629 goto done_proto;
630 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
631 goto done;
632 m_copydata(m, off, sizeof (th), (caddr_t) &th);
633 spidx->src.sin.sin_port = th.th_sport;
634 spidx->dst.sin.sin_port = th.th_dport;
635 return;
636 case IPPROTO_UDP:
637 spidx->ul_proto = nxt;
638 if (!needport)
639 goto done_proto;
640 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
641 goto done;
642 m_copydata(m, off, sizeof (uh), (caddr_t) &uh);
643 spidx->src.sin.sin_port = uh.uh_sport;
644 spidx->dst.sin.sin_port = uh.uh_dport;
645 return;
646 case IPPROTO_AH:
647 if (off + sizeof(ip6e) > m->m_pkthdr.len)
648 goto done;
649 /* XXX Sigh, this works but is totally bogus. */
650 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e);
651 off += (ip6e.ip6e_len + 2) << 2;
652 nxt = ip6e.ip6e_nxt;
653 break;
654 case IPPROTO_ICMP:
655 default:
656 /* XXX Intermediate headers??? */
657 spidx->ul_proto = nxt;
658 goto done_proto;
659 }
660 }
661 done:
662 spidx->ul_proto = IPSEC_ULPROTO_ANY;
663 done_proto:
664 spidx->src.sin.sin_port = IPSEC_PORT_ANY;
665 spidx->dst.sin.sin_port = IPSEC_PORT_ANY;
666 }
667
668 /* Assumes that m is sane. */
669 static int
670 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
671 {
672 static const struct sockaddr_in template = {
673 sizeof (struct sockaddr_in),
674 AF_INET,
675 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 }
676 };
677
678 spidx->src.sin = template;
679 spidx->dst.sin = template;
680
681 if (m->m_len < sizeof (struct ip)) {
682 m_copydata(m, offsetof(struct ip, ip_src),
683 sizeof (struct in_addr),
684 (caddr_t) &spidx->src.sin.sin_addr);
685 m_copydata(m, offsetof(struct ip, ip_dst),
686 sizeof (struct in_addr),
687 (caddr_t) &spidx->dst.sin.sin_addr);
688 } else {
689 struct ip *ip = mtod(m, struct ip *);
690 spidx->src.sin.sin_addr = ip->ip_src;
691 spidx->dst.sin.sin_addr = ip->ip_dst;
692 }
693
694 spidx->prefs = sizeof(struct in_addr) << 3;
695 spidx->prefd = sizeof(struct in_addr) << 3;
696
697 return (0);
698 }
699
700 #ifdef INET6
701 static void
702 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
703 {
704 int off, nxt;
705 struct tcphdr th;
706 struct udphdr uh;
707 struct icmp6_hdr ih;
708
709 /* Sanity check. */
710 if (m == NULL)
711 panic("%s: NULL pointer was passed.\n", __func__);
712
713 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
714 printf("%s:\n", __func__); kdebug_mbuf(m));
715
716 /* Set default. */
717 spidx->ul_proto = IPSEC_ULPROTO_ANY;
718 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY;
719 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY;
720
721 nxt = -1;
722 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
723 if (off < 0 || m->m_pkthdr.len < off)
724 return;
725
726 switch (nxt) {
727 case IPPROTO_TCP:
728 spidx->ul_proto = nxt;
729 if (!needport)
730 break;
731 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
732 break;
733 m_copydata(m, off, sizeof(th), (caddr_t)&th);
734 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport;
735 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport;
736 break;
737 case IPPROTO_UDP:
738 spidx->ul_proto = nxt;
739 if (!needport)
740 break;
741 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
742 break;
743 m_copydata(m, off, sizeof(uh), (caddr_t)&uh);
744 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport;
745 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport;
746 break;
747 case IPPROTO_ICMPV6:
748 spidx->ul_proto = nxt;
749 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len)
750 break;
751 m_copydata(m, off, sizeof(ih), (caddr_t)&ih);
752 ((struct sockaddr_in6 *)&spidx->src)->sin6_port =
753 htons((uint16_t)ih.icmp6_type);
754 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port =
755 htons((uint16_t)ih.icmp6_code);
756 break;
757 default:
758 /* XXX Intermediate headers??? */
759 spidx->ul_proto = nxt;
760 break;
761 }
762 }
763
764 /* Assumes that m is sane. */
765 static int
766 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
767 {
768 struct ip6_hdr *ip6 = NULL;
769 struct ip6_hdr ip6buf;
770 struct sockaddr_in6 *sin6;
771
772 if (m->m_len >= sizeof(*ip6))
773 ip6 = mtod(m, struct ip6_hdr *);
774 else {
775 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf);
776 ip6 = &ip6buf;
777 }
778
779 sin6 = (struct sockaddr_in6 *)&spidx->src;
780 bzero(sin6, sizeof(*sin6));
781 sin6->sin6_family = AF_INET6;
782 sin6->sin6_len = sizeof(struct sockaddr_in6);
783 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src));
784 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
785 sin6->sin6_addr.s6_addr16[1] = 0;
786 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]);
787 }
788 spidx->prefs = sizeof(struct in6_addr) << 3;
789
790 sin6 = (struct sockaddr_in6 *)&spidx->dst;
791 bzero(sin6, sizeof(*sin6));
792 sin6->sin6_family = AF_INET6;
793 sin6->sin6_len = sizeof(struct sockaddr_in6);
794 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst));
795 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
796 sin6->sin6_addr.s6_addr16[1] = 0;
797 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
798 }
799 spidx->prefd = sizeof(struct in6_addr) << 3;
800
801 return (0);
802 }
803 #endif
804
805 static void
806 ipsec_delpcbpolicy(struct inpcbpolicy *p)
807 {
808
809 free(p, M_IPSEC_INPCB);
810 }
811
812 /* Initialize policy in PCB. */
813 int
814 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp)
815 {
816 struct inpcbpolicy *new;
817
818 /* Sanity check. */
819 if (so == NULL || pcb_sp == NULL)
820 panic("%s: NULL pointer was passed.\n", __func__);
821
822 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy),
823 M_IPSEC_INPCB, M_NOWAIT|M_ZERO);
824 if (new == NULL) {
825 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
826 return (ENOBUFS);
827 }
828
829 new->priv = IPSEC_IS_PRIVILEGED_SO(so);
830
831 if ((new->sp_in = KEY_NEWSP()) == NULL) {
832 ipsec_delpcbpolicy(new);
833 return (ENOBUFS);
834 }
835 new->sp_in->state = IPSEC_SPSTATE_ALIVE;
836 new->sp_in->policy = IPSEC_POLICY_ENTRUST;
837
838 if ((new->sp_out = KEY_NEWSP()) == NULL) {
839 KEY_FREESP(&new->sp_in);
840 ipsec_delpcbpolicy(new);
841 return (ENOBUFS);
842 }
843 new->sp_out->state = IPSEC_SPSTATE_ALIVE;
844 new->sp_out->policy = IPSEC_POLICY_ENTRUST;
845
846 *pcb_sp = new;
847
848 return (0);
849 }
850
851 /* Copy old IPsec policy into new. */
852 int
853 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new)
854 {
855 struct secpolicy *sp;
856
857 sp = ipsec_deepcopy_policy(old->sp_in);
858 if (sp) {
859 KEY_FREESP(&new->sp_in);
860 new->sp_in = sp;
861 } else
862 return (ENOBUFS);
863
864 sp = ipsec_deepcopy_policy(old->sp_out);
865 if (sp) {
866 KEY_FREESP(&new->sp_out);
867 new->sp_out = sp;
868 } else
869 return (ENOBUFS);
870
871 new->priv = old->priv;
872
873 return (0);
874 }
875
876 struct ipsecrequest *
877 ipsec_newisr(void)
878 {
879 struct ipsecrequest *p;
880
881 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO);
882 if (p != NULL)
883 IPSECREQUEST_LOCK_INIT(p);
884 return (p);
885 }
886
887 void
888 ipsec_delisr(struct ipsecrequest *p)
889 {
890
891 IPSECREQUEST_LOCK_DESTROY(p);
892 free(p, M_IPSEC_SR);
893 }
894
895 /* Deep-copy a policy in PCB. */
896 static struct secpolicy *
897 ipsec_deepcopy_policy(struct secpolicy *src)
898 {
899 struct ipsecrequest *newchain = NULL;
900 struct ipsecrequest *p;
901 struct ipsecrequest **q;
902 struct ipsecrequest *r;
903 struct secpolicy *dst;
904
905 if (src == NULL)
906 return (NULL);
907 dst = KEY_NEWSP();
908 if (dst == NULL)
909 return (NULL);
910
911 /*
912 * Deep-copy IPsec request chain. This is required since struct
913 * ipsecrequest is not reference counted.
914 */
915 q = &newchain;
916 for (p = src->req; p; p = p->next) {
917 *q = ipsec_newisr();
918 if (*q == NULL)
919 goto fail;
920 (*q)->saidx.proto = p->saidx.proto;
921 (*q)->saidx.mode = p->saidx.mode;
922 (*q)->level = p->level;
923 (*q)->saidx.reqid = p->saidx.reqid;
924
925 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src));
926 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst));
927
928 (*q)->sp = dst;
929
930 q = &((*q)->next);
931 }
932
933 dst->req = newchain;
934 dst->state = src->state;
935 dst->policy = src->policy;
936 /* Do not touch the refcnt fields. */
937
938 return (dst);
939
940 fail:
941 for (p = newchain; p; p = r) {
942 r = p->next;
943 ipsec_delisr(p);
944 p = NULL;
945 }
946 return (NULL);
947 }
948
949 /* Set policy and IPsec request if present. */
950 static int
951 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname,
952 caddr_t request, size_t len, struct ucred *cred)
953 {
954 struct sadb_x_policy *xpl;
955 struct secpolicy *newsp = NULL;
956 int error;
957
958 /* Sanity check. */
959 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL)
960 return (EINVAL);
961 if (len < sizeof(*xpl))
962 return (EINVAL);
963 xpl = (struct sadb_x_policy *)request;
964
965 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
966 printf("%s: passed policy\n", __func__);
967 kdebug_sadb_x_policy((struct sadb_ext *)xpl));
968
969 /* Check policy type. */
970 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */
971 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD
972 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE)
973 return (EINVAL);
974
975 /* Check privileged socket. */
976 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) {
977 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0);
978 if (error)
979 return (EACCES);
980 }
981
982 /* Allocating new SP entry. */
983 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL)
984 return (error);
985
986 newsp->state = IPSEC_SPSTATE_ALIVE;
987
988 /* Clear old SP and set new SP. */
989 KEY_FREESP(pcb_sp);
990 *pcb_sp = newsp;
991 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
992 printf("%s: new policy\n", __func__);
993 kdebug_secpolicy(newsp));
994
995 return (0);
996 }
997
998 int
999 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request,
1000 size_t len, struct ucred *cred)
1001 {
1002 struct sadb_x_policy *xpl;
1003 struct secpolicy **pcb_sp;
1004
1005 /* Sanity check. */
1006 if (inp == NULL || request == NULL)
1007 return (EINVAL);
1008 if (len < sizeof(*xpl))
1009 return (EINVAL);
1010 xpl = (struct sadb_x_policy *)request;
1011
1012 /* Select direction. */
1013 switch (xpl->sadb_x_policy_dir) {
1014 case IPSEC_DIR_INBOUND:
1015 pcb_sp = &inp->inp_sp->sp_in;
1016 break;
1017 case IPSEC_DIR_OUTBOUND:
1018 pcb_sp = &inp->inp_sp->sp_out;
1019 break;
1020 default:
1021 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1022 xpl->sadb_x_policy_dir));
1023 return (EINVAL);
1024 }
1025
1026 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred));
1027 }
1028
1029 int
1030 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len,
1031 struct mbuf **mp)
1032 {
1033 struct sadb_x_policy *xpl;
1034 struct secpolicy *pcb_sp;
1035
1036 /* Sanity check. */
1037 if (inp == NULL || request == NULL || mp == NULL)
1038 return (EINVAL);
1039 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
1040 if (len < sizeof(*xpl))
1041 return (EINVAL);
1042 xpl = (struct sadb_x_policy *)request;
1043
1044 /* Select direction. */
1045 switch (xpl->sadb_x_policy_dir) {
1046 case IPSEC_DIR_INBOUND:
1047 pcb_sp = inp->inp_sp->sp_in;
1048 break;
1049 case IPSEC_DIR_OUTBOUND:
1050 pcb_sp = inp->inp_sp->sp_out;
1051 break;
1052 default:
1053 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1054 xpl->sadb_x_policy_dir));
1055 return (EINVAL);
1056 }
1057
1058 /* Sanity check. Should be an IPSEC_ASSERT. */
1059 if (pcb_sp == NULL)
1060 return (EINVAL);
1061
1062 *mp = key_sp2msg(pcb_sp);
1063 if (!*mp) {
1064 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
1065 return (ENOBUFS);
1066 }
1067
1068 (*mp)->m_type = MT_DATA;
1069 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1070 printf("%s:\n", __func__); kdebug_mbuf(*mp));
1071
1072 return (0);
1073 }
1074
1075 /* Delete policy in PCB. */
1076 int
1077 ipsec_delete_pcbpolicy(struct inpcb *inp)
1078 {
1079 IPSEC_ASSERT(inp != NULL, ("null inp"));
1080
1081 if (inp->inp_sp == NULL)
1082 return (0);
1083
1084 if (inp->inp_sp->sp_in != NULL)
1085 KEY_FREESP(&inp->inp_sp->sp_in);
1086
1087 if (inp->inp_sp->sp_out != NULL)
1088 KEY_FREESP(&inp->inp_sp->sp_out);
1089
1090 ipsec_delpcbpolicy(inp->inp_sp);
1091 inp->inp_sp = NULL;
1092
1093 return (0);
1094 }
1095
1096 /*
1097 * Return current level.
1098 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned.
1099 */
1100 u_int
1101 ipsec_get_reqlevel(struct ipsecrequest *isr)
1102 {
1103 u_int level = 0;
1104 u_int esp_trans_deflev, esp_net_deflev;
1105 u_int ah_trans_deflev, ah_net_deflev;
1106
1107 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument"));
1108 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family,
1109 ("af family mismatch, src %u, dst %u",
1110 isr->sp->spidx.src.sa.sa_family,
1111 isr->sp->spidx.dst.sa.sa_family));
1112
1113 /* XXX Note that we have ipseclog() expanded here - code sync issue. */
1114 #define IPSEC_CHECK_DEFAULT(lev) \
1115 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \
1116 && (lev) != IPSEC_LEVEL_UNIQUE) \
1117 ? (V_ipsec_debug \
1118 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\
1119 (lev), IPSEC_LEVEL_REQUIRE) \
1120 : 0), \
1121 (lev) = IPSEC_LEVEL_REQUIRE, \
1122 (lev) \
1123 : (lev))
1124
1125 /* Set default level. */
1126 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) {
1127 #ifdef INET
1128 case AF_INET:
1129 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev);
1130 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev);
1131 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev);
1132 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev);
1133 break;
1134 #endif
1135 #ifdef INET6
1136 case AF_INET6:
1137 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev);
1138 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev);
1139 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev);
1140 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev);
1141 break;
1142 #endif /* INET6 */
1143 default:
1144 panic("%s: unknown af %u",
1145 __func__, isr->sp->spidx.src.sa.sa_family);
1146 }
1147
1148 #undef IPSEC_CHECK_DEFAULT
1149
1150 /* Set level. */
1151 switch (isr->level) {
1152 case IPSEC_LEVEL_DEFAULT:
1153 switch (isr->saidx.proto) {
1154 case IPPROTO_ESP:
1155 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1156 level = esp_net_deflev;
1157 else
1158 level = esp_trans_deflev;
1159 break;
1160 case IPPROTO_AH:
1161 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1162 level = ah_net_deflev;
1163 else
1164 level = ah_trans_deflev;
1165 break;
1166 case IPPROTO_IPCOMP:
1167 /*
1168 * We don't really care, as IPcomp document says that
1169 * we shouldn't compress small packets.
1170 */
1171 level = IPSEC_LEVEL_USE;
1172 break;
1173 default:
1174 panic("%s: Illegal protocol defined %u\n", __func__,
1175 isr->saidx.proto);
1176 }
1177 break;
1178
1179 case IPSEC_LEVEL_USE:
1180 case IPSEC_LEVEL_REQUIRE:
1181 level = isr->level;
1182 break;
1183 case IPSEC_LEVEL_UNIQUE:
1184 level = IPSEC_LEVEL_REQUIRE;
1185 break;
1186
1187 default:
1188 panic("%s: Illegal IPsec level %u\n", __func__, isr->level);
1189 }
1190
1191 return (level);
1192 }
1193
1194 /*
1195 * Check security policy requirements against the actual
1196 * packet contents. Return one if the packet should be
1197 * reject as "invalid"; otherwiser return zero to have the
1198 * packet treated as "valid".
1199 *
1200 * OUT:
1201 * 0: valid
1202 * 1: invalid
1203 */
1204 int
1205 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m)
1206 {
1207 struct ipsecrequest *isr;
1208 int need_auth;
1209
1210 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1211 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1212
1213 /* Check policy. */
1214 switch (sp->policy) {
1215 case IPSEC_POLICY_DISCARD:
1216 return (1);
1217 case IPSEC_POLICY_BYPASS:
1218 case IPSEC_POLICY_NONE:
1219 return (0);
1220 }
1221
1222 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1223 ("invalid policy %u", sp->policy));
1224
1225 /* XXX Should compare policy against IPsec header history. */
1226
1227 need_auth = 0;
1228 for (isr = sp->req; isr != NULL; isr = isr->next) {
1229 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE)
1230 continue;
1231 switch (isr->saidx.proto) {
1232 case IPPROTO_ESP:
1233 if ((m->m_flags & M_DECRYPTED) == 0) {
1234 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1235 printf("%s: ESP m_flags:%x\n", __func__,
1236 m->m_flags));
1237 return (1);
1238 }
1239
1240 if (!need_auth &&
1241 isr->sav != NULL &&
1242 isr->sav->tdb_authalgxform != NULL &&
1243 (m->m_flags & M_AUTHIPDGM) == 0) {
1244 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1245 printf("%s: ESP/AH m_flags:%x\n", __func__,
1246 m->m_flags));
1247 return (1);
1248 }
1249 break;
1250 case IPPROTO_AH:
1251 need_auth = 1;
1252 if ((m->m_flags & M_AUTHIPHDR) == 0) {
1253 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1254 printf("%s: AH m_flags:%x\n", __func__,
1255 m->m_flags));
1256 return (1);
1257 }
1258 break;
1259 case IPPROTO_IPCOMP:
1260 /*
1261 * We don't really care, as IPcomp document
1262 * says that we shouldn't compress small
1263 * packets. IPComp policy should always be
1264 * treated as being in "use" level.
1265 */
1266 break;
1267 }
1268 }
1269 return (0); /* Valid. */
1270 }
1271
1272 static int
1273 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp)
1274 {
1275 struct secpolicy *sp;
1276 int error;
1277 int result;
1278
1279 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1280
1281 /*
1282 * Get SP for this packet.
1283 * When we are called from ip_forward(), we call
1284 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1285 */
1286 if (inp == NULL)
1287 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error);
1288 else
1289 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error);
1290
1291 if (sp != NULL) {
1292 result = ipsec_in_reject(sp, m);
1293 KEY_FREESP(&sp);
1294 } else {
1295 result = 0; /* XXX Should be panic?
1296 * -> No, there may be error. */
1297 }
1298 return (result);
1299 }
1300
1301 /*
1302 * Check AH/ESP integrity.
1303 * This function is called from tcp_input(), udp_input(),
1304 * and {ah,esp}4_input for tunnel mode.
1305 */
1306 int
1307 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp)
1308 {
1309 int result;
1310
1311 result = ipsec46_in_reject(m, inp);
1312 if (result)
1313 V_ipsec4stat.ips_in_polvio++;
1314
1315 return (result);
1316 }
1317
1318 #ifdef INET6
1319 /*
1320 * Check AH/ESP integrity.
1321 * This function is called from tcp6_input(), udp6_input(),
1322 * and {ah,esp}6_input for tunnel mode.
1323 */
1324 int
1325 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp)
1326 {
1327 int result;
1328
1329 result = ipsec46_in_reject(m, inp);
1330 if (result)
1331 V_ipsec6stat.ips_in_polvio++;
1332
1333 return (result);
1334 }
1335 #endif
1336
1337 /*
1338 * Compute the byte size to be occupied by IPsec header.
1339 * In case it is tunnelled, it includes the size of outer IP header.
1340 * NOTE: SP passed is freed in this function.
1341 */
1342 static size_t
1343 ipsec_hdrsiz_internal(struct secpolicy *sp)
1344 {
1345 struct ipsecrequest *isr;
1346 size_t size;
1347
1348 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1349 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1350
1351 switch (sp->policy) {
1352 case IPSEC_POLICY_DISCARD:
1353 case IPSEC_POLICY_BYPASS:
1354 case IPSEC_POLICY_NONE:
1355 return (0);
1356 }
1357
1358 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1359 ("invalid policy %u", sp->policy));
1360
1361 size = 0;
1362 for (isr = sp->req; isr != NULL; isr = isr->next) {
1363 size_t clen = 0;
1364
1365 switch (isr->saidx.proto) {
1366 case IPPROTO_ESP:
1367 clen = esp_hdrsiz(isr->sav);
1368 break;
1369 case IPPROTO_AH:
1370 clen = ah_hdrsiz(isr->sav);
1371 break;
1372 case IPPROTO_IPCOMP:
1373 clen = sizeof(struct ipcomp);
1374 break;
1375 }
1376
1377 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
1378 switch (isr->saidx.dst.sa.sa_family) {
1379 case AF_INET:
1380 clen += sizeof(struct ip);
1381 break;
1382 #ifdef INET6
1383 case AF_INET6:
1384 clen += sizeof(struct ip6_hdr);
1385 break;
1386 #endif
1387 default:
1388 ipseclog((LOG_ERR, "%s: unknown AF %d in "
1389 "IPsec tunnel SA\n", __func__,
1390 ((struct sockaddr *)&isr->saidx.dst)->sa_family));
1391 break;
1392 }
1393 }
1394 size += clen;
1395 }
1396
1397 return (size);
1398 }
1399
1400 /*
1401 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(),
1402 * disabled ip6_ipsec_mtu() and ip6_forward().
1403 */
1404 size_t
1405 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp)
1406 {
1407 struct secpolicy *sp;
1408 int error;
1409 size_t size;
1410
1411 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1412
1413 /* Get SP for this packet.
1414 * When we are called from ip_forward(), we call
1415 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1416 */
1417 if (inp == NULL)
1418 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error);
1419 else
1420 sp = ipsec_getpolicybysock(m, dir, inp, &error);
1421
1422 if (sp != NULL) {
1423 size = ipsec_hdrsiz_internal(sp);
1424 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1425 printf("%s: size:%lu.\n", __func__,
1426 (unsigned long)size));
1427
1428 KEY_FREESP(&sp);
1429 } else {
1430 size = 0; /* XXX Should be panic?
1431 * -> No, we are called w/o knowing if
1432 * IPsec processing is needed. */
1433 }
1434 return (size);
1435 }
1436
1437 /*
1438 * Check the variable replay window.
1439 * ipsec_chkreplay() performs replay check before ICV verification.
1440 * ipsec_updatereplay() updates replay bitmap. This must be called after
1441 * ICV verification (it also performs replay check, which is usually done
1442 * beforehand).
1443 * 0 (zero) is returned if packet disallowed, 1 if packet permitted.
1444 *
1445 * Based on RFC 2401.
1446 */
1447 int
1448 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav)
1449 {
1450 const struct secreplay *replay;
1451 u_int32_t diff;
1452 int fr;
1453 u_int32_t wsizeb; /* Constant: bits of window size. */
1454 int frlast; /* Constant: last frame. */
1455
1456 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1457 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1458
1459 replay = sav->replay;
1460
1461 if (replay->wsize == 0)
1462 return (1); /* No need to check replay. */
1463
1464 /* Constant. */
1465 frlast = replay->wsize - 1;
1466 wsizeb = replay->wsize << 3;
1467
1468 /* Sequence number of 0 is invalid. */
1469 if (seq == 0)
1470 return (0);
1471
1472 /* First time is always okay. */
1473 if (replay->count == 0)
1474 return (1);
1475
1476 if (seq > replay->lastseq) {
1477 /* Larger sequences are okay. */
1478 return (1);
1479 } else {
1480 /* seq is equal or less than lastseq. */
1481 diff = replay->lastseq - seq;
1482
1483 /* Over range to check, i.e. too old or wrapped. */
1484 if (diff >= wsizeb)
1485 return (0);
1486
1487 fr = frlast - diff / 8;
1488
1489 /* This packet already seen? */
1490 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1491 return (0);
1492
1493 /* Out of order but good. */
1494 return (1);
1495 }
1496 }
1497
1498 /*
1499 * Check replay counter whether to update or not.
1500 * OUT: 0: OK
1501 * 1: NG
1502 */
1503 int
1504 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav)
1505 {
1506 struct secreplay *replay;
1507 u_int32_t diff;
1508 int fr;
1509 u_int32_t wsizeb; /* Constant: bits of window size. */
1510 int frlast; /* Constant: last frame. */
1511
1512 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1513 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1514
1515 replay = sav->replay;
1516
1517 if (replay->wsize == 0)
1518 goto ok; /* No need to check replay. */
1519
1520 /* Constant. */
1521 frlast = replay->wsize - 1;
1522 wsizeb = replay->wsize << 3;
1523
1524 /* Sequence number of 0 is invalid. */
1525 if (seq == 0)
1526 return (1);
1527
1528 /* First time. */
1529 if (replay->count == 0) {
1530 replay->lastseq = seq;
1531 bzero(replay->bitmap, replay->wsize);
1532 (replay->bitmap)[frlast] = 1;
1533 goto ok;
1534 }
1535
1536 if (seq > replay->lastseq) {
1537 /* seq is larger than lastseq. */
1538 diff = seq - replay->lastseq;
1539
1540 /* New larger sequence number. */
1541 if (diff < wsizeb) {
1542 /* In window. */
1543 /* Set bit for this packet. */
1544 vshiftl(replay->bitmap, diff, replay->wsize);
1545 (replay->bitmap)[frlast] |= 1;
1546 } else {
1547 /* This packet has a "way larger". */
1548 bzero(replay->bitmap, replay->wsize);
1549 (replay->bitmap)[frlast] = 1;
1550 }
1551 replay->lastseq = seq;
1552
1553 /* Larger is good. */
1554 } else {
1555 /* seq is equal or less than lastseq. */
1556 diff = replay->lastseq - seq;
1557
1558 /* Over range to check, i.e. too old or wrapped. */
1559 if (diff >= wsizeb)
1560 return (1);
1561
1562 fr = frlast - diff / 8;
1563
1564 /* This packet already seen? */
1565 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1566 return (1);
1567
1568 /* Mark as seen. */
1569 (replay->bitmap)[fr] |= (1 << (diff % 8));
1570
1571 /* Out of order but good. */
1572 }
1573
1574 ok:
1575 if (replay->count == ~0) {
1576
1577 /* Set overflow flag. */
1578 replay->overflow++;
1579
1580 /* Don't increment, no more packets accepted. */
1581 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0)
1582 return (1);
1583
1584 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n",
1585 __func__, replay->overflow, ipsec_logsastr(sav)));
1586 }
1587
1588 replay->count++;
1589
1590 return (0);
1591 }
1592
1593 /*
1594 * Shift variable length buffer to left.
1595 * IN: bitmap: pointer to the buffer
1596 * nbit: the number of to shift.
1597 * wsize: buffer size (bytes).
1598 */
1599 static void
1600 vshiftl(unsigned char *bitmap, int nbit, int wsize)
1601 {
1602 int s, j, i;
1603 unsigned char over;
1604
1605 for (j = 0; j < nbit; j += 8) {
1606 s = (nbit - j < 8) ? (nbit - j): 8;
1607 bitmap[0] <<= s;
1608 for (i = 1; i < wsize; i++) {
1609 over = (bitmap[i] >> (8 - s));
1610 bitmap[i] <<= s;
1611 bitmap[i-1] |= over;
1612 }
1613 }
1614 }
1615
1616 #ifdef INET
1617 /* Return a printable string for the IPv4 address. */
1618 static char *
1619 inet_ntoa4(struct in_addr ina)
1620 {
1621 static char buf[4][4 * sizeof "123" + 4];
1622 unsigned char *ucp = (unsigned char *) &ina;
1623 static int i = 3;
1624
1625 /* XXX-BZ Returns static buffer. */
1626 i = (i + 1) % 4;
1627 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff,
1628 ucp[2] & 0xff, ucp[3] & 0xff);
1629 return (buf[i]);
1630 }
1631 #endif
1632
1633 /* Return a printable string for the address. */
1634 char *
1635 ipsec_address(union sockaddr_union* sa)
1636 {
1637 #ifdef INET6
1638 char ip6buf[INET6_ADDRSTRLEN];
1639 #endif
1640
1641 switch (sa->sa.sa_family) {
1642 #ifdef INET
1643 case AF_INET:
1644 return (inet_ntoa4(sa->sin.sin_addr));
1645 #endif /* INET */
1646 #ifdef INET6
1647 case AF_INET6:
1648 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr));
1649 #endif /* INET6 */
1650 default:
1651 return ("(unknown address family)");
1652 }
1653 }
1654
1655 const char *
1656 ipsec_logsastr(struct secasvar *sav)
1657 {
1658 static char buf[256];
1659 char *p;
1660 struct secasindex *saidx = &sav->sah->saidx;
1661
1662 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family,
1663 ("address family mismatch"));
1664
1665 p = buf;
1666 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi));
1667 while (p && *p)
1668 p++;
1669 /* NB: only use ipsec_address on one address at a time. */
1670 snprintf(p, sizeof (buf) - (p - buf), "src=%s ",
1671 ipsec_address(&saidx->src));
1672 while (p && *p)
1673 p++;
1674 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)",
1675 ipsec_address(&saidx->dst));
1676
1677 return (buf);
1678 }
1679
1680 void
1681 ipsec_dumpmbuf(struct mbuf *m)
1682 {
1683 int totlen;
1684 int i;
1685 u_char *p;
1686
1687 totlen = 0;
1688 printf("---\n");
1689 while (m) {
1690 p = mtod(m, u_char *);
1691 for (i = 0; i < m->m_len; i++) {
1692 printf("%02x ", p[i]);
1693 totlen++;
1694 if (totlen % 16 == 0)
1695 printf("\n");
1696 }
1697 m = m->m_next;
1698 }
1699 if (totlen % 16 != 0)
1700 printf("\n");
1701 printf("---\n");
1702 }
1703
1704 static void
1705 ipsec_init(const void *unused __unused)
1706 {
1707
1708 SECPOLICY_LOCK_INIT(&V_ip4_def_policy);
1709 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */
1710 }
1711 VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init,
1712 NULL);
1713
1714
1715 /* XXX This stuff doesn't belong here... */
1716
1717 static struct xformsw* xforms = NULL;
1718
1719 /*
1720 * Register a transform; typically at system startup.
1721 */
1722 void
1723 xform_register(struct xformsw* xsp)
1724 {
1725
1726 xsp->xf_next = xforms;
1727 xforms = xsp;
1728 }
1729
1730 /*
1731 * Initialize transform support in an sav.
1732 */
1733 int
1734 xform_init(struct secasvar *sav, int xftype)
1735 {
1736 struct xformsw *xsp;
1737
1738 if (sav->tdb_xform != NULL) /* Previously initialized. */
1739 return (0);
1740 for (xsp = xforms; xsp; xsp = xsp->xf_next)
1741 if (xsp->xf_type == xftype)
1742 return ((*xsp->xf_init)(sav, xsp));
1743 return (EINVAL);
1744 }
Cache object: 3b1b9cf16f3c10a480ec93a596ea341b
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