FreeBSD/Linux Kernel Cross Reference
sys/netipsec/ipsec.c
1 /* $FreeBSD: releng/10.0/sys/netipsec/ipsec.c 253088 2013-07-09 10:08:13Z ae $ */
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_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat);
108 VNET_PCPUSTAT_SYSINIT(ipsec4stat);
109
110 #ifdef VIMAGE
111 VNET_PCPUSTAT_SYSUNINIT(ipsec4stat);
112 #endif /* VIMAGE */
113
114 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */
115 /* DF bit on encap. 0: clear 1: set 2: copy */
116 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0;
117 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE;
118 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE;
119 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE;
120 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE;
121 VNET_DEFINE(struct secpolicy, ip4_def_policy);
122 /* ECN ignore(-1)/forbidden(0)/allowed(1) */
123 VNET_DEFINE(int, ip4_ipsec_ecn) = 0;
124 VNET_DEFINE(int, ip4_esp_randpad) = -1;
125
126 /*
127 * Crypto support requirements:
128 *
129 * 1 require hardware support
130 * -1 require software support
131 * 0 take anything
132 */
133 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE;
134
135 FEATURE(ipsec, "Internet Protocol Security (IPsec)");
136 #ifdef IPSEC_NAT_T
137 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')");
138 #endif
139
140 SYSCTL_DECL(_net_inet_ipsec);
141
142 /* net.inet.ipsec */
143 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy,
144 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0,
145 "IPsec default policy.");
146 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
147 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0,
148 "Default ESP transport mode level");
149 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
150 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0,
151 "Default ESP tunnel mode level.");
152 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
153 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0,
154 "AH transfer mode default level.");
155 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
156 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0,
157 "AH tunnel mode default level.");
158 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos,
159 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0,
160 "If set clear type-of-service field when doing AH computation.");
161 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask,
162 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0,
163 "If not set clear offset field mask when doing AH computation.");
164 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit,
165 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0,
166 "Do not fragment bit on encap.");
167 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn,
168 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0,
169 "Explicit Congestion Notification handling.");
170 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug,
171 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0,
172 "Enable IPsec debugging output when set.");
173 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support,
174 CTLFLAG_RW, &VNET_NAME(crypto_support), 0,
175 "Crypto driver selection.");
176 SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat,
177 ipsec4stat, "IPsec IPv4 statistics.");
178
179 #ifdef REGRESSION
180 /*
181 * When set to 1, IPsec will send packets with the same sequence number.
182 * This allows to verify if the other side has proper replay attacks detection.
183 */
184 VNET_DEFINE(int, ipsec_replay) = 0;
185 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay,
186 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0,
187 "Emulate replay attack");
188 /*
189 * When set 1, IPsec will send packets with corrupted HMAC.
190 * This allows to verify if the other side properly detects modified packets.
191 */
192 VNET_DEFINE(int, ipsec_integrity) = 0;
193 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity,
194 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0,
195 "Emulate man-in-the-middle attack");
196 #endif
197
198 #ifdef INET6
199 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat);
200 VNET_PCPUSTAT_SYSINIT(ipsec6stat);
201
202 #ifdef VIMAGE
203 VNET_PCPUSTAT_SYSUNINIT(ipsec6stat);
204 #endif /* VIMAGE */
205
206 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE;
207 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE;
208 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE;
209 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE;
210 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */
211
212 SYSCTL_DECL(_net_inet6_ipsec6);
213
214 /* net.inet6.ipsec6 */
215 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW,
216 &VNET_NAME(ip4_def_policy).policy, 0,
217 "IPsec default policy.");
218 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV,
219 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0,
220 "Default ESP transport mode level.");
221 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV,
222 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0,
223 "Default ESP tunnel mode level.");
224 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV,
225 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0,
226 "AH transfer mode default level.");
227 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV,
228 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0,
229 "AH tunnel mode default level.");
230 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN,
231 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0,
232 "Explicit Congestion Notification handling.");
233 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW,
234 &VNET_NAME(ipsec_debug), 0,
235 "Enable IPsec debugging output when set.");
236 SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats,
237 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics.");
238 #endif /* INET6 */
239
240 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *));
241 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int));
242 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int));
243 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *));
244 #ifdef INET6
245 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int));
246 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *));
247 #endif
248 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *));
249 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src));
250 static void vshiftl __P((unsigned char *, int, int));
251
252 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy");
253
254 /*
255 * Return a held reference to the default SP.
256 */
257 static struct secpolicy *
258 key_allocsp_default(const char* where, int tag)
259 {
260 struct secpolicy *sp;
261
262 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
263 printf("DP key_allocsp_default from %s:%u\n", where, tag));
264
265 sp = &V_ip4_def_policy;
266 if (sp->policy != IPSEC_POLICY_DISCARD &&
267 sp->policy != IPSEC_POLICY_NONE) {
268 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n",
269 sp->policy, IPSEC_POLICY_NONE));
270 sp->policy = IPSEC_POLICY_NONE;
271 }
272 key_addref(sp);
273
274 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
275 printf("DP key_allocsp_default returns SP:%p (%u)\n",
276 sp, sp->refcnt));
277 return (sp);
278 }
279 #define KEY_ALLOCSP_DEFAULT() \
280 key_allocsp_default(__FILE__, __LINE__)
281
282 /*
283 * For OUTBOUND packet having a socket. Searching SPD for packet,
284 * and return a pointer to SP.
285 * OUT: NULL: no apropreate SP found, the following value is set to error.
286 * 0 : bypass
287 * EACCES : discard packet.
288 * ENOENT : ipsec_acquire() in progress, maybe.
289 * others : error occured.
290 * others: a pointer to SP
291 *
292 * NOTE: IPv6 mapped adddress concern is implemented here.
293 */
294 struct secpolicy *
295 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir)
296 {
297 struct secpolicy *sp;
298
299 IPSEC_ASSERT(tdbi != NULL, ("null tdbi"));
300 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
301 ("invalid direction %u", dir));
302
303 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir);
304 if (sp == NULL) /*XXX????*/
305 sp = KEY_ALLOCSP_DEFAULT();
306 IPSEC_ASSERT(sp != NULL, ("null SP"));
307 return (sp);
308 }
309
310 /*
311 * For OUTBOUND packet having a socket. Searching SPD for packet,
312 * and return a pointer to SP.
313 * OUT: NULL: no apropreate SP found, the following value is set to error.
314 * 0 : bypass
315 * EACCES : discard packet.
316 * ENOENT : ipsec_acquire() in progress, maybe.
317 * others : error occured.
318 * others: a pointer to SP
319 *
320 * NOTE: IPv6 mapped adddress concern is implemented here.
321 */
322 static struct secpolicy *
323 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error)
324 {
325 struct inpcbpolicy *pcbsp;
326 struct secpolicy *currsp = NULL; /* Policy on socket. */
327 struct secpolicy *sp;
328
329 IPSEC_ASSERT(m != NULL, ("null mbuf"));
330 IPSEC_ASSERT(inp != NULL, ("null inpcb"));
331 IPSEC_ASSERT(error != NULL, ("null error"));
332 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
333 ("invalid direction %u", dir));
334
335 /* Set spidx in pcb. */
336 *error = ipsec_setspidx_inpcb(m, inp);
337 if (*error)
338 return (NULL);
339
340 pcbsp = inp->inp_sp;
341 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp"));
342 switch (dir) {
343 case IPSEC_DIR_INBOUND:
344 currsp = pcbsp->sp_in;
345 break;
346 case IPSEC_DIR_OUTBOUND:
347 currsp = pcbsp->sp_out;
348 break;
349 }
350 IPSEC_ASSERT(currsp != NULL, ("null currsp"));
351
352 if (pcbsp->priv) { /* When privilieged socket. */
353 switch (currsp->policy) {
354 case IPSEC_POLICY_BYPASS:
355 case IPSEC_POLICY_IPSEC:
356 key_addref(currsp);
357 sp = currsp;
358 break;
359
360 case IPSEC_POLICY_ENTRUST:
361 /* Look for a policy in SPD. */
362 sp = KEY_ALLOCSP(&currsp->spidx, dir);
363 if (sp == NULL) /* No SP found. */
364 sp = KEY_ALLOCSP_DEFAULT();
365 break;
366
367 default:
368 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n",
369 __func__, currsp->policy));
370 *error = EINVAL;
371 return (NULL);
372 }
373 } else { /* Unpriv, SPD has policy. */
374 sp = KEY_ALLOCSP(&currsp->spidx, dir);
375 if (sp == NULL) { /* No SP found. */
376 switch (currsp->policy) {
377 case IPSEC_POLICY_BYPASS:
378 ipseclog((LOG_ERR, "%s: Illegal policy for "
379 "non-priviliged defined %d\n",
380 __func__, currsp->policy));
381 *error = EINVAL;
382 return (NULL);
383
384 case IPSEC_POLICY_ENTRUST:
385 sp = KEY_ALLOCSP_DEFAULT();
386 break;
387
388 case IPSEC_POLICY_IPSEC:
389 key_addref(currsp);
390 sp = currsp;
391 break;
392
393 default:
394 ipseclog((LOG_ERR, "%s: Invalid policy for "
395 "PCB %d\n", __func__, currsp->policy));
396 *error = EINVAL;
397 return (NULL);
398 }
399 }
400 }
401 IPSEC_ASSERT(sp != NULL,
402 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy));
403 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
404 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n",
405 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt));
406 return (sp);
407 }
408
409 /*
410 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet,
411 * and return a pointer to SP.
412 * OUT: positive: a pointer to the entry for security policy leaf matched.
413 * NULL: no apropreate SP found, the following value is set to error.
414 * 0 : bypass
415 * EACCES : discard packet.
416 * ENOENT : ipsec_acquire() in progress, maybe.
417 * others : error occured.
418 */
419 struct secpolicy *
420 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error)
421 {
422 struct secpolicyindex spidx;
423 struct secpolicy *sp;
424
425 IPSEC_ASSERT(m != NULL, ("null mbuf"));
426 IPSEC_ASSERT(error != NULL, ("null error"));
427 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
428 ("invalid direction %u", dir));
429
430 sp = NULL;
431 if (key_havesp(dir)) {
432 /* Make an index to look for a policy. */
433 *error = ipsec_setspidx(m, &spidx,
434 (flag & IP_FORWARDING) ? 0 : 1);
435 if (*error != 0) {
436 DPRINTF(("%s: setpidx failed, dir %u flag %u\n",
437 __func__, dir, flag));
438 return (NULL);
439 }
440 spidx.dir = dir;
441
442 sp = KEY_ALLOCSP(&spidx, dir);
443 }
444 if (sp == NULL) /* No SP found, use system default. */
445 sp = KEY_ALLOCSP_DEFAULT();
446 IPSEC_ASSERT(sp != NULL, ("null SP"));
447 return (sp);
448 }
449
450 struct secpolicy *
451 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error,
452 struct inpcb *inp)
453 {
454 struct secpolicy *sp;
455
456 *error = 0;
457 if (inp == NULL)
458 sp = ipsec_getpolicybyaddr(m, dir, flag, error);
459 else
460 sp = ipsec_getpolicybysock(m, dir, inp, error);
461 if (sp == NULL) {
462 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error"));
463 IPSECSTAT_INC(ips_out_inval);
464 return (NULL);
465 }
466 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error));
467 switch (sp->policy) {
468 case IPSEC_POLICY_ENTRUST:
469 default:
470 printf("%s: invalid policy %u\n", __func__, sp->policy);
471 /* FALLTHROUGH */
472 case IPSEC_POLICY_DISCARD:
473 IPSECSTAT_INC(ips_out_polvio);
474 *error = -EINVAL; /* Packet is discarded by caller. */
475 break;
476 case IPSEC_POLICY_BYPASS:
477 case IPSEC_POLICY_NONE:
478 KEY_FREESP(&sp);
479 sp = NULL; /* NB: force NULL result. */
480 break;
481 case IPSEC_POLICY_IPSEC:
482 if (sp->req == NULL) /* Acquire a SA. */
483 *error = key_spdacquire(sp);
484 break;
485 }
486 if (*error != 0) {
487 KEY_FREESP(&sp);
488 sp = NULL;
489 }
490 return (sp);
491 }
492
493 static int
494 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp)
495 {
496 int error;
497
498 IPSEC_ASSERT(inp != NULL, ("null inp"));
499 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
500 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL,
501 ("null sp_in || sp_out"));
502
503 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1);
504 if (error == 0) {
505 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND;
506 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx;
507 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND;
508 } else {
509 bzero(&inp->inp_sp->sp_in->spidx,
510 sizeof (inp->inp_sp->sp_in->spidx));
511 bzero(&inp->inp_sp->sp_out->spidx,
512 sizeof (inp->inp_sp->sp_in->spidx));
513 }
514 return (error);
515 }
516
517 /*
518 * Configure security policy index (src/dst/proto/sport/dport)
519 * by looking at the content of mbuf.
520 * The caller is responsible for error recovery (like clearing up spidx).
521 */
522 static int
523 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport)
524 {
525 struct ip *ip = NULL;
526 struct ip ipbuf;
527 u_int v;
528 struct mbuf *n;
529 int len;
530 int error;
531
532 IPSEC_ASSERT(m != NULL, ("null mbuf"));
533
534 /*
535 * Validate m->m_pkthdr.len. We see incorrect length if we
536 * mistakenly call this function with inconsistent mbuf chain
537 * (like 4.4BSD tcp/udp processing). XXX Should we panic here?
538 */
539 len = 0;
540 for (n = m; n; n = n->m_next)
541 len += n->m_len;
542 if (m->m_pkthdr.len != len) {
543 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
544 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n",
545 __func__, len, m->m_pkthdr.len));
546 return (EINVAL);
547 }
548
549 if (m->m_pkthdr.len < sizeof(struct ip)) {
550 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
551 printf("%s: pkthdr len(%d) too small (v4), ignored.\n",
552 __func__, m->m_pkthdr.len));
553 return (EINVAL);
554 }
555
556 if (m->m_len >= sizeof(*ip))
557 ip = mtod(m, struct ip *);
558 else {
559 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf);
560 ip = &ipbuf;
561 }
562 #ifdef _IP_VHL
563 v = _IP_VHL_V(ip->ip_vhl);
564 #else
565 v = ip->ip_v;
566 #endif
567 switch (v) {
568 case 4:
569 error = ipsec4_setspidx_ipaddr(m, spidx);
570 if (error)
571 return (error);
572 ipsec4_get_ulp(m, spidx, needport);
573 return (0);
574 #ifdef INET6
575 case 6:
576 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) {
577 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
578 printf("%s: pkthdr len(%d) too small (v6), "
579 "ignored\n", __func__, m->m_pkthdr.len));
580 return (EINVAL);
581 }
582 error = ipsec6_setspidx_ipaddr(m, spidx);
583 if (error)
584 return (error);
585 ipsec6_get_ulp(m, spidx, needport);
586 return (0);
587 #endif
588 default:
589 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
590 printf("%s: " "unknown IP version %u, ignored.\n",
591 __func__, v));
592 return (EINVAL);
593 }
594 }
595
596 static void
597 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
598 {
599 u_int8_t nxt;
600 int off;
601
602 /* Sanity check. */
603 IPSEC_ASSERT(m != NULL, ("null mbuf"));
604 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short"));
605
606 if (m->m_len >= sizeof (struct ip)) {
607 struct ip *ip = mtod(m, struct ip *);
608 if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
609 goto done;
610 #ifdef _IP_VHL
611 off = _IP_VHL_HL(ip->ip_vhl) << 2;
612 #else
613 off = ip->ip_hl << 2;
614 #endif
615 nxt = ip->ip_p;
616 } else {
617 struct ip ih;
618
619 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih);
620 if (ih.ip_off & htons(IP_MF | IP_OFFMASK))
621 goto done;
622 #ifdef _IP_VHL
623 off = _IP_VHL_HL(ih.ip_vhl) << 2;
624 #else
625 off = ih.ip_hl << 2;
626 #endif
627 nxt = ih.ip_p;
628 }
629
630 while (off < m->m_pkthdr.len) {
631 struct ip6_ext ip6e;
632 struct tcphdr th;
633 struct udphdr uh;
634
635 switch (nxt) {
636 case IPPROTO_TCP:
637 spidx->ul_proto = nxt;
638 if (!needport)
639 goto done_proto;
640 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
641 goto done;
642 m_copydata(m, off, sizeof (th), (caddr_t) &th);
643 spidx->src.sin.sin_port = th.th_sport;
644 spidx->dst.sin.sin_port = th.th_dport;
645 return;
646 case IPPROTO_UDP:
647 spidx->ul_proto = nxt;
648 if (!needport)
649 goto done_proto;
650 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
651 goto done;
652 m_copydata(m, off, sizeof (uh), (caddr_t) &uh);
653 spidx->src.sin.sin_port = uh.uh_sport;
654 spidx->dst.sin.sin_port = uh.uh_dport;
655 return;
656 case IPPROTO_AH:
657 if (off + sizeof(ip6e) > m->m_pkthdr.len)
658 goto done;
659 /* XXX Sigh, this works but is totally bogus. */
660 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e);
661 off += (ip6e.ip6e_len + 2) << 2;
662 nxt = ip6e.ip6e_nxt;
663 break;
664 case IPPROTO_ICMP:
665 default:
666 /* XXX Intermediate headers??? */
667 spidx->ul_proto = nxt;
668 goto done_proto;
669 }
670 }
671 done:
672 spidx->ul_proto = IPSEC_ULPROTO_ANY;
673 done_proto:
674 spidx->src.sin.sin_port = IPSEC_PORT_ANY;
675 spidx->dst.sin.sin_port = IPSEC_PORT_ANY;
676 }
677
678 /* Assumes that m is sane. */
679 static int
680 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
681 {
682 static const struct sockaddr_in template = {
683 sizeof (struct sockaddr_in),
684 AF_INET,
685 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 }
686 };
687
688 spidx->src.sin = template;
689 spidx->dst.sin = template;
690
691 if (m->m_len < sizeof (struct ip)) {
692 m_copydata(m, offsetof(struct ip, ip_src),
693 sizeof (struct in_addr),
694 (caddr_t) &spidx->src.sin.sin_addr);
695 m_copydata(m, offsetof(struct ip, ip_dst),
696 sizeof (struct in_addr),
697 (caddr_t) &spidx->dst.sin.sin_addr);
698 } else {
699 struct ip *ip = mtod(m, struct ip *);
700 spidx->src.sin.sin_addr = ip->ip_src;
701 spidx->dst.sin.sin_addr = ip->ip_dst;
702 }
703
704 spidx->prefs = sizeof(struct in_addr) << 3;
705 spidx->prefd = sizeof(struct in_addr) << 3;
706
707 return (0);
708 }
709
710 #ifdef INET6
711 static void
712 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
713 {
714 int off, nxt;
715 struct tcphdr th;
716 struct udphdr uh;
717 struct icmp6_hdr ih;
718
719 /* Sanity check. */
720 if (m == NULL)
721 panic("%s: NULL pointer was passed.\n", __func__);
722
723 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
724 printf("%s:\n", __func__); kdebug_mbuf(m));
725
726 /* Set default. */
727 spidx->ul_proto = IPSEC_ULPROTO_ANY;
728 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY;
729 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY;
730
731 nxt = -1;
732 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
733 if (off < 0 || m->m_pkthdr.len < off)
734 return;
735
736 switch (nxt) {
737 case IPPROTO_TCP:
738 spidx->ul_proto = nxt;
739 if (!needport)
740 break;
741 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
742 break;
743 m_copydata(m, off, sizeof(th), (caddr_t)&th);
744 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport;
745 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport;
746 break;
747 case IPPROTO_UDP:
748 spidx->ul_proto = nxt;
749 if (!needport)
750 break;
751 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
752 break;
753 m_copydata(m, off, sizeof(uh), (caddr_t)&uh);
754 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport;
755 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport;
756 break;
757 case IPPROTO_ICMPV6:
758 spidx->ul_proto = nxt;
759 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len)
760 break;
761 m_copydata(m, off, sizeof(ih), (caddr_t)&ih);
762 ((struct sockaddr_in6 *)&spidx->src)->sin6_port =
763 htons((uint16_t)ih.icmp6_type);
764 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port =
765 htons((uint16_t)ih.icmp6_code);
766 break;
767 default:
768 /* XXX Intermediate headers??? */
769 spidx->ul_proto = nxt;
770 break;
771 }
772 }
773
774 /* Assumes that m is sane. */
775 static int
776 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
777 {
778 struct ip6_hdr *ip6 = NULL;
779 struct ip6_hdr ip6buf;
780 struct sockaddr_in6 *sin6;
781
782 if (m->m_len >= sizeof(*ip6))
783 ip6 = mtod(m, struct ip6_hdr *);
784 else {
785 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf);
786 ip6 = &ip6buf;
787 }
788
789 sin6 = (struct sockaddr_in6 *)&spidx->src;
790 bzero(sin6, sizeof(*sin6));
791 sin6->sin6_family = AF_INET6;
792 sin6->sin6_len = sizeof(struct sockaddr_in6);
793 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src));
794 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
795 sin6->sin6_addr.s6_addr16[1] = 0;
796 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]);
797 }
798 spidx->prefs = sizeof(struct in6_addr) << 3;
799
800 sin6 = (struct sockaddr_in6 *)&spidx->dst;
801 bzero(sin6, sizeof(*sin6));
802 sin6->sin6_family = AF_INET6;
803 sin6->sin6_len = sizeof(struct sockaddr_in6);
804 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst));
805 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
806 sin6->sin6_addr.s6_addr16[1] = 0;
807 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
808 }
809 spidx->prefd = sizeof(struct in6_addr) << 3;
810
811 return (0);
812 }
813 #endif
814
815 static void
816 ipsec_delpcbpolicy(struct inpcbpolicy *p)
817 {
818
819 free(p, M_IPSEC_INPCB);
820 }
821
822 /* Initialize policy in PCB. */
823 int
824 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp)
825 {
826 struct inpcbpolicy *new;
827
828 /* Sanity check. */
829 if (so == NULL || pcb_sp == NULL)
830 panic("%s: NULL pointer was passed.\n", __func__);
831
832 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy),
833 M_IPSEC_INPCB, M_NOWAIT|M_ZERO);
834 if (new == NULL) {
835 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
836 return (ENOBUFS);
837 }
838
839 new->priv = IPSEC_IS_PRIVILEGED_SO(so);
840
841 if ((new->sp_in = KEY_NEWSP()) == NULL) {
842 ipsec_delpcbpolicy(new);
843 return (ENOBUFS);
844 }
845 new->sp_in->state = IPSEC_SPSTATE_ALIVE;
846 new->sp_in->policy = IPSEC_POLICY_ENTRUST;
847
848 if ((new->sp_out = KEY_NEWSP()) == NULL) {
849 KEY_FREESP(&new->sp_in);
850 ipsec_delpcbpolicy(new);
851 return (ENOBUFS);
852 }
853 new->sp_out->state = IPSEC_SPSTATE_ALIVE;
854 new->sp_out->policy = IPSEC_POLICY_ENTRUST;
855
856 *pcb_sp = new;
857
858 return (0);
859 }
860
861 /* Copy old IPsec policy into new. */
862 int
863 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new)
864 {
865 struct secpolicy *sp;
866
867 sp = ipsec_deepcopy_policy(old->sp_in);
868 if (sp) {
869 KEY_FREESP(&new->sp_in);
870 new->sp_in = sp;
871 } else
872 return (ENOBUFS);
873
874 sp = ipsec_deepcopy_policy(old->sp_out);
875 if (sp) {
876 KEY_FREESP(&new->sp_out);
877 new->sp_out = sp;
878 } else
879 return (ENOBUFS);
880
881 new->priv = old->priv;
882
883 return (0);
884 }
885
886 struct ipsecrequest *
887 ipsec_newisr(void)
888 {
889 struct ipsecrequest *p;
890
891 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO);
892 if (p != NULL)
893 IPSECREQUEST_LOCK_INIT(p);
894 return (p);
895 }
896
897 void
898 ipsec_delisr(struct ipsecrequest *p)
899 {
900
901 IPSECREQUEST_LOCK_DESTROY(p);
902 free(p, M_IPSEC_SR);
903 }
904
905 /* Deep-copy a policy in PCB. */
906 static struct secpolicy *
907 ipsec_deepcopy_policy(struct secpolicy *src)
908 {
909 struct ipsecrequest *newchain = NULL;
910 struct ipsecrequest *p;
911 struct ipsecrequest **q;
912 struct ipsecrequest *r;
913 struct secpolicy *dst;
914
915 if (src == NULL)
916 return (NULL);
917 dst = KEY_NEWSP();
918 if (dst == NULL)
919 return (NULL);
920
921 /*
922 * Deep-copy IPsec request chain. This is required since struct
923 * ipsecrequest is not reference counted.
924 */
925 q = &newchain;
926 for (p = src->req; p; p = p->next) {
927 *q = ipsec_newisr();
928 if (*q == NULL)
929 goto fail;
930 (*q)->saidx.proto = p->saidx.proto;
931 (*q)->saidx.mode = p->saidx.mode;
932 (*q)->level = p->level;
933 (*q)->saidx.reqid = p->saidx.reqid;
934
935 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src));
936 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst));
937
938 (*q)->sp = dst;
939
940 q = &((*q)->next);
941 }
942
943 dst->req = newchain;
944 dst->state = src->state;
945 dst->policy = src->policy;
946 /* Do not touch the refcnt fields. */
947
948 return (dst);
949
950 fail:
951 for (p = newchain; p; p = r) {
952 r = p->next;
953 ipsec_delisr(p);
954 p = NULL;
955 }
956 return (NULL);
957 }
958
959 /* Set policy and IPsec request if present. */
960 static int
961 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname,
962 caddr_t request, size_t len, struct ucred *cred)
963 {
964 struct sadb_x_policy *xpl;
965 struct secpolicy *newsp = NULL;
966 int error;
967
968 /* Sanity check. */
969 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL)
970 return (EINVAL);
971 if (len < sizeof(*xpl))
972 return (EINVAL);
973 xpl = (struct sadb_x_policy *)request;
974
975 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
976 printf("%s: passed policy\n", __func__);
977 kdebug_sadb_x_policy((struct sadb_ext *)xpl));
978
979 /* Check policy type. */
980 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */
981 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD
982 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE)
983 return (EINVAL);
984
985 /* Check privileged socket. */
986 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) {
987 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0);
988 if (error)
989 return (EACCES);
990 }
991
992 /* Allocating new SP entry. */
993 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL)
994 return (error);
995
996 newsp->state = IPSEC_SPSTATE_ALIVE;
997
998 /* Clear old SP and set new SP. */
999 KEY_FREESP(pcb_sp);
1000 *pcb_sp = newsp;
1001 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1002 printf("%s: new policy\n", __func__);
1003 kdebug_secpolicy(newsp));
1004
1005 return (0);
1006 }
1007
1008 int
1009 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request,
1010 size_t len, struct ucred *cred)
1011 {
1012 struct sadb_x_policy *xpl;
1013 struct secpolicy **pcb_sp;
1014
1015 /* Sanity check. */
1016 if (inp == NULL || request == NULL)
1017 return (EINVAL);
1018 if (len < sizeof(*xpl))
1019 return (EINVAL);
1020 xpl = (struct sadb_x_policy *)request;
1021
1022 /* Select direction. */
1023 switch (xpl->sadb_x_policy_dir) {
1024 case IPSEC_DIR_INBOUND:
1025 pcb_sp = &inp->inp_sp->sp_in;
1026 break;
1027 case IPSEC_DIR_OUTBOUND:
1028 pcb_sp = &inp->inp_sp->sp_out;
1029 break;
1030 default:
1031 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1032 xpl->sadb_x_policy_dir));
1033 return (EINVAL);
1034 }
1035
1036 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred));
1037 }
1038
1039 int
1040 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len,
1041 struct mbuf **mp)
1042 {
1043 struct sadb_x_policy *xpl;
1044 struct secpolicy *pcb_sp;
1045
1046 /* Sanity check. */
1047 if (inp == NULL || request == NULL || mp == NULL)
1048 return (EINVAL);
1049 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
1050 if (len < sizeof(*xpl))
1051 return (EINVAL);
1052 xpl = (struct sadb_x_policy *)request;
1053
1054 /* Select direction. */
1055 switch (xpl->sadb_x_policy_dir) {
1056 case IPSEC_DIR_INBOUND:
1057 pcb_sp = inp->inp_sp->sp_in;
1058 break;
1059 case IPSEC_DIR_OUTBOUND:
1060 pcb_sp = inp->inp_sp->sp_out;
1061 break;
1062 default:
1063 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1064 xpl->sadb_x_policy_dir));
1065 return (EINVAL);
1066 }
1067
1068 /* Sanity check. Should be an IPSEC_ASSERT. */
1069 if (pcb_sp == NULL)
1070 return (EINVAL);
1071
1072 *mp = key_sp2msg(pcb_sp);
1073 if (!*mp) {
1074 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
1075 return (ENOBUFS);
1076 }
1077
1078 (*mp)->m_type = MT_DATA;
1079 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1080 printf("%s:\n", __func__); kdebug_mbuf(*mp));
1081
1082 return (0);
1083 }
1084
1085 /* Delete policy in PCB. */
1086 int
1087 ipsec_delete_pcbpolicy(struct inpcb *inp)
1088 {
1089 IPSEC_ASSERT(inp != NULL, ("null inp"));
1090
1091 if (inp->inp_sp == NULL)
1092 return (0);
1093
1094 if (inp->inp_sp->sp_in != NULL)
1095 KEY_FREESP(&inp->inp_sp->sp_in);
1096
1097 if (inp->inp_sp->sp_out != NULL)
1098 KEY_FREESP(&inp->inp_sp->sp_out);
1099
1100 ipsec_delpcbpolicy(inp->inp_sp);
1101 inp->inp_sp = NULL;
1102
1103 return (0);
1104 }
1105
1106 /*
1107 * Return current level.
1108 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned.
1109 */
1110 u_int
1111 ipsec_get_reqlevel(struct ipsecrequest *isr)
1112 {
1113 u_int level = 0;
1114 u_int esp_trans_deflev, esp_net_deflev;
1115 u_int ah_trans_deflev, ah_net_deflev;
1116
1117 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument"));
1118 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family,
1119 ("af family mismatch, src %u, dst %u",
1120 isr->sp->spidx.src.sa.sa_family,
1121 isr->sp->spidx.dst.sa.sa_family));
1122
1123 /* XXX Note that we have ipseclog() expanded here - code sync issue. */
1124 #define IPSEC_CHECK_DEFAULT(lev) \
1125 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \
1126 && (lev) != IPSEC_LEVEL_UNIQUE) \
1127 ? (V_ipsec_debug \
1128 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\
1129 (lev), IPSEC_LEVEL_REQUIRE) \
1130 : 0), \
1131 (lev) = IPSEC_LEVEL_REQUIRE, \
1132 (lev) \
1133 : (lev))
1134
1135 /* Set default level. */
1136 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) {
1137 #ifdef INET
1138 case AF_INET:
1139 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev);
1140 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev);
1141 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev);
1142 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev);
1143 break;
1144 #endif
1145 #ifdef INET6
1146 case AF_INET6:
1147 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev);
1148 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev);
1149 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev);
1150 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev);
1151 break;
1152 #endif /* INET6 */
1153 default:
1154 panic("%s: unknown af %u",
1155 __func__, isr->sp->spidx.src.sa.sa_family);
1156 }
1157
1158 #undef IPSEC_CHECK_DEFAULT
1159
1160 /* Set level. */
1161 switch (isr->level) {
1162 case IPSEC_LEVEL_DEFAULT:
1163 switch (isr->saidx.proto) {
1164 case IPPROTO_ESP:
1165 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1166 level = esp_net_deflev;
1167 else
1168 level = esp_trans_deflev;
1169 break;
1170 case IPPROTO_AH:
1171 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1172 level = ah_net_deflev;
1173 else
1174 level = ah_trans_deflev;
1175 break;
1176 case IPPROTO_IPCOMP:
1177 /*
1178 * We don't really care, as IPcomp document says that
1179 * we shouldn't compress small packets.
1180 */
1181 level = IPSEC_LEVEL_USE;
1182 break;
1183 default:
1184 panic("%s: Illegal protocol defined %u\n", __func__,
1185 isr->saidx.proto);
1186 }
1187 break;
1188
1189 case IPSEC_LEVEL_USE:
1190 case IPSEC_LEVEL_REQUIRE:
1191 level = isr->level;
1192 break;
1193 case IPSEC_LEVEL_UNIQUE:
1194 level = IPSEC_LEVEL_REQUIRE;
1195 break;
1196
1197 default:
1198 panic("%s: Illegal IPsec level %u\n", __func__, isr->level);
1199 }
1200
1201 return (level);
1202 }
1203
1204 /*
1205 * Check security policy requirements against the actual
1206 * packet contents. Return one if the packet should be
1207 * reject as "invalid"; otherwiser return zero to have the
1208 * packet treated as "valid".
1209 *
1210 * OUT:
1211 * 0: valid
1212 * 1: invalid
1213 */
1214 int
1215 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m)
1216 {
1217 struct ipsecrequest *isr;
1218 int need_auth;
1219
1220 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1221 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1222
1223 /* Check policy. */
1224 switch (sp->policy) {
1225 case IPSEC_POLICY_DISCARD:
1226 return (1);
1227 case IPSEC_POLICY_BYPASS:
1228 case IPSEC_POLICY_NONE:
1229 return (0);
1230 }
1231
1232 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1233 ("invalid policy %u", sp->policy));
1234
1235 /* XXX Should compare policy against IPsec header history. */
1236
1237 need_auth = 0;
1238 for (isr = sp->req; isr != NULL; isr = isr->next) {
1239 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE)
1240 continue;
1241 switch (isr->saidx.proto) {
1242 case IPPROTO_ESP:
1243 if ((m->m_flags & M_DECRYPTED) == 0) {
1244 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1245 printf("%s: ESP m_flags:%x\n", __func__,
1246 m->m_flags));
1247 return (1);
1248 }
1249
1250 if (!need_auth &&
1251 isr->sav != NULL &&
1252 isr->sav->tdb_authalgxform != NULL &&
1253 (m->m_flags & M_AUTHIPDGM) == 0) {
1254 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1255 printf("%s: ESP/AH m_flags:%x\n", __func__,
1256 m->m_flags));
1257 return (1);
1258 }
1259 break;
1260 case IPPROTO_AH:
1261 need_auth = 1;
1262 if ((m->m_flags & M_AUTHIPHDR) == 0) {
1263 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1264 printf("%s: AH m_flags:%x\n", __func__,
1265 m->m_flags));
1266 return (1);
1267 }
1268 break;
1269 case IPPROTO_IPCOMP:
1270 /*
1271 * We don't really care, as IPcomp document
1272 * says that we shouldn't compress small
1273 * packets. IPComp policy should always be
1274 * treated as being in "use" level.
1275 */
1276 break;
1277 }
1278 }
1279 return (0); /* Valid. */
1280 }
1281
1282 static int
1283 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp)
1284 {
1285 struct secpolicy *sp;
1286 int error;
1287 int result;
1288
1289 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1290
1291 /*
1292 * Get SP for this packet.
1293 * When we are called from ip_forward(), we call
1294 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1295 */
1296 if (inp == NULL)
1297 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error);
1298 else
1299 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error);
1300
1301 if (sp != NULL) {
1302 result = ipsec_in_reject(sp, m);
1303 KEY_FREESP(&sp);
1304 } else {
1305 result = 0; /* XXX Should be panic?
1306 * -> No, there may be error. */
1307 }
1308 return (result);
1309 }
1310
1311 /*
1312 * Check AH/ESP integrity.
1313 * This function is called from tcp_input(), udp_input(),
1314 * and {ah,esp}4_input for tunnel mode.
1315 */
1316 int
1317 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp)
1318 {
1319 int result;
1320
1321 result = ipsec46_in_reject(m, inp);
1322 if (result)
1323 IPSECSTAT_INC(ips_in_polvio);
1324
1325 return (result);
1326 }
1327
1328 #ifdef INET6
1329 /*
1330 * Check AH/ESP integrity.
1331 * This function is called from tcp6_input(), udp6_input(),
1332 * and {ah,esp}6_input for tunnel mode.
1333 */
1334 int
1335 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp)
1336 {
1337 int result;
1338
1339 result = ipsec46_in_reject(m, inp);
1340 if (result)
1341 IPSEC6STAT_INC(ips_in_polvio);
1342
1343 return (result);
1344 }
1345 #endif
1346
1347 /*
1348 * Compute the byte size to be occupied by IPsec header.
1349 * In case it is tunnelled, it includes the size of outer IP header.
1350 * NOTE: SP passed is freed in this function.
1351 */
1352 static size_t
1353 ipsec_hdrsiz_internal(struct secpolicy *sp)
1354 {
1355 struct ipsecrequest *isr;
1356 size_t size;
1357
1358 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1359 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1360
1361 switch (sp->policy) {
1362 case IPSEC_POLICY_DISCARD:
1363 case IPSEC_POLICY_BYPASS:
1364 case IPSEC_POLICY_NONE:
1365 return (0);
1366 }
1367
1368 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1369 ("invalid policy %u", sp->policy));
1370
1371 size = 0;
1372 for (isr = sp->req; isr != NULL; isr = isr->next) {
1373 size_t clen = 0;
1374
1375 switch (isr->saidx.proto) {
1376 case IPPROTO_ESP:
1377 clen = esp_hdrsiz(isr->sav);
1378 break;
1379 case IPPROTO_AH:
1380 clen = ah_hdrsiz(isr->sav);
1381 break;
1382 case IPPROTO_IPCOMP:
1383 clen = sizeof(struct ipcomp);
1384 break;
1385 }
1386
1387 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
1388 switch (isr->saidx.dst.sa.sa_family) {
1389 case AF_INET:
1390 clen += sizeof(struct ip);
1391 break;
1392 #ifdef INET6
1393 case AF_INET6:
1394 clen += sizeof(struct ip6_hdr);
1395 break;
1396 #endif
1397 default:
1398 ipseclog((LOG_ERR, "%s: unknown AF %d in "
1399 "IPsec tunnel SA\n", __func__,
1400 ((struct sockaddr *)&isr->saidx.dst)->sa_family));
1401 break;
1402 }
1403 }
1404 size += clen;
1405 }
1406
1407 return (size);
1408 }
1409
1410 /*
1411 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(),
1412 * disabled ip6_ipsec_mtu() and ip6_forward().
1413 */
1414 size_t
1415 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp)
1416 {
1417 struct secpolicy *sp;
1418 int error;
1419 size_t size;
1420
1421 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1422
1423 /* Get SP for this packet.
1424 * When we are called from ip_forward(), we call
1425 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1426 */
1427 if (inp == NULL)
1428 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error);
1429 else
1430 sp = ipsec_getpolicybysock(m, dir, inp, &error);
1431
1432 if (sp != NULL) {
1433 size = ipsec_hdrsiz_internal(sp);
1434 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1435 printf("%s: size:%lu.\n", __func__,
1436 (unsigned long)size));
1437
1438 KEY_FREESP(&sp);
1439 } else {
1440 size = 0; /* XXX Should be panic?
1441 * -> No, we are called w/o knowing if
1442 * IPsec processing is needed. */
1443 }
1444 return (size);
1445 }
1446
1447 /*
1448 * Check the variable replay window.
1449 * ipsec_chkreplay() performs replay check before ICV verification.
1450 * ipsec_updatereplay() updates replay bitmap. This must be called after
1451 * ICV verification (it also performs replay check, which is usually done
1452 * beforehand).
1453 * 0 (zero) is returned if packet disallowed, 1 if packet permitted.
1454 *
1455 * Based on RFC 2401.
1456 */
1457 int
1458 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav)
1459 {
1460 const struct secreplay *replay;
1461 u_int32_t diff;
1462 int fr;
1463 u_int32_t wsizeb; /* Constant: bits of window size. */
1464 int frlast; /* Constant: last frame. */
1465
1466 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1467 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1468
1469 replay = sav->replay;
1470
1471 if (replay->wsize == 0)
1472 return (1); /* No need to check replay. */
1473
1474 /* Constant. */
1475 frlast = replay->wsize - 1;
1476 wsizeb = replay->wsize << 3;
1477
1478 /* Sequence number of 0 is invalid. */
1479 if (seq == 0)
1480 return (0);
1481
1482 /* First time is always okay. */
1483 if (replay->count == 0)
1484 return (1);
1485
1486 if (seq > replay->lastseq) {
1487 /* Larger sequences are okay. */
1488 return (1);
1489 } else {
1490 /* seq is equal or less than lastseq. */
1491 diff = replay->lastseq - seq;
1492
1493 /* Over range to check, i.e. too old or wrapped. */
1494 if (diff >= wsizeb)
1495 return (0);
1496
1497 fr = frlast - diff / 8;
1498
1499 /* This packet already seen? */
1500 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1501 return (0);
1502
1503 /* Out of order but good. */
1504 return (1);
1505 }
1506 }
1507
1508 /*
1509 * Check replay counter whether to update or not.
1510 * OUT: 0: OK
1511 * 1: NG
1512 */
1513 int
1514 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav)
1515 {
1516 struct secreplay *replay;
1517 u_int32_t diff;
1518 int fr;
1519 u_int32_t wsizeb; /* Constant: bits of window size. */
1520 int frlast; /* Constant: last frame. */
1521
1522 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1523 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1524
1525 replay = sav->replay;
1526
1527 if (replay->wsize == 0)
1528 goto ok; /* No need to check replay. */
1529
1530 /* Constant. */
1531 frlast = replay->wsize - 1;
1532 wsizeb = replay->wsize << 3;
1533
1534 /* Sequence number of 0 is invalid. */
1535 if (seq == 0)
1536 return (1);
1537
1538 /* First time. */
1539 if (replay->count == 0) {
1540 replay->lastseq = seq;
1541 bzero(replay->bitmap, replay->wsize);
1542 (replay->bitmap)[frlast] = 1;
1543 goto ok;
1544 }
1545
1546 if (seq > replay->lastseq) {
1547 /* seq is larger than lastseq. */
1548 diff = seq - replay->lastseq;
1549
1550 /* New larger sequence number. */
1551 if (diff < wsizeb) {
1552 /* In window. */
1553 /* Set bit for this packet. */
1554 vshiftl(replay->bitmap, diff, replay->wsize);
1555 (replay->bitmap)[frlast] |= 1;
1556 } else {
1557 /* This packet has a "way larger". */
1558 bzero(replay->bitmap, replay->wsize);
1559 (replay->bitmap)[frlast] = 1;
1560 }
1561 replay->lastseq = seq;
1562
1563 /* Larger is good. */
1564 } else {
1565 /* seq is equal or less than lastseq. */
1566 diff = replay->lastseq - seq;
1567
1568 /* Over range to check, i.e. too old or wrapped. */
1569 if (diff >= wsizeb)
1570 return (1);
1571
1572 fr = frlast - diff / 8;
1573
1574 /* This packet already seen? */
1575 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1576 return (1);
1577
1578 /* Mark as seen. */
1579 (replay->bitmap)[fr] |= (1 << (diff % 8));
1580
1581 /* Out of order but good. */
1582 }
1583
1584 ok:
1585 if (replay->count == ~0) {
1586
1587 /* Set overflow flag. */
1588 replay->overflow++;
1589
1590 /* Don't increment, no more packets accepted. */
1591 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0)
1592 return (1);
1593
1594 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n",
1595 __func__, replay->overflow, ipsec_logsastr(sav)));
1596 }
1597
1598 replay->count++;
1599
1600 return (0);
1601 }
1602
1603 /*
1604 * Shift variable length buffer to left.
1605 * IN: bitmap: pointer to the buffer
1606 * nbit: the number of to shift.
1607 * wsize: buffer size (bytes).
1608 */
1609 static void
1610 vshiftl(unsigned char *bitmap, int nbit, int wsize)
1611 {
1612 int s, j, i;
1613 unsigned char over;
1614
1615 for (j = 0; j < nbit; j += 8) {
1616 s = (nbit - j < 8) ? (nbit - j): 8;
1617 bitmap[0] <<= s;
1618 for (i = 1; i < wsize; i++) {
1619 over = (bitmap[i] >> (8 - s));
1620 bitmap[i] <<= s;
1621 bitmap[i-1] |= over;
1622 }
1623 }
1624 }
1625
1626 #ifdef INET
1627 /* Return a printable string for the IPv4 address. */
1628 static char *
1629 inet_ntoa4(struct in_addr ina)
1630 {
1631 static char buf[4][4 * sizeof "123" + 4];
1632 unsigned char *ucp = (unsigned char *) &ina;
1633 static int i = 3;
1634
1635 /* XXX-BZ Returns static buffer. */
1636 i = (i + 1) % 4;
1637 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff,
1638 ucp[2] & 0xff, ucp[3] & 0xff);
1639 return (buf[i]);
1640 }
1641 #endif
1642
1643 /* Return a printable string for the address. */
1644 char *
1645 ipsec_address(union sockaddr_union* sa)
1646 {
1647 #ifdef INET6
1648 char ip6buf[INET6_ADDRSTRLEN];
1649 #endif
1650
1651 switch (sa->sa.sa_family) {
1652 #ifdef INET
1653 case AF_INET:
1654 return (inet_ntoa4(sa->sin.sin_addr));
1655 #endif /* INET */
1656 #ifdef INET6
1657 case AF_INET6:
1658 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr));
1659 #endif /* INET6 */
1660 default:
1661 return ("(unknown address family)");
1662 }
1663 }
1664
1665 const char *
1666 ipsec_logsastr(struct secasvar *sav)
1667 {
1668 static char buf[256];
1669 char *p;
1670 struct secasindex *saidx = &sav->sah->saidx;
1671
1672 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family,
1673 ("address family mismatch"));
1674
1675 p = buf;
1676 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi));
1677 while (p && *p)
1678 p++;
1679 /* NB: only use ipsec_address on one address at a time. */
1680 snprintf(p, sizeof (buf) - (p - buf), "src=%s ",
1681 ipsec_address(&saidx->src));
1682 while (p && *p)
1683 p++;
1684 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)",
1685 ipsec_address(&saidx->dst));
1686
1687 return (buf);
1688 }
1689
1690 void
1691 ipsec_dumpmbuf(struct mbuf *m)
1692 {
1693 int totlen;
1694 int i;
1695 u_char *p;
1696
1697 totlen = 0;
1698 printf("---\n");
1699 while (m) {
1700 p = mtod(m, u_char *);
1701 for (i = 0; i < m->m_len; i++) {
1702 printf("%02x ", p[i]);
1703 totlen++;
1704 if (totlen % 16 == 0)
1705 printf("\n");
1706 }
1707 m = m->m_next;
1708 }
1709 if (totlen % 16 != 0)
1710 printf("\n");
1711 printf("---\n");
1712 }
1713
1714 static void
1715 ipsec_init(const void *unused __unused)
1716 {
1717
1718 SECPOLICY_LOCK_INIT(&V_ip4_def_policy);
1719 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */
1720 }
1721 VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init,
1722 NULL);
1723
1724
1725 /* XXX This stuff doesn't belong here... */
1726
1727 static struct xformsw* xforms = NULL;
1728
1729 /*
1730 * Register a transform; typically at system startup.
1731 */
1732 void
1733 xform_register(struct xformsw* xsp)
1734 {
1735
1736 xsp->xf_next = xforms;
1737 xforms = xsp;
1738 }
1739
1740 /*
1741 * Initialize transform support in an sav.
1742 */
1743 int
1744 xform_init(struct secasvar *sav, int xftype)
1745 {
1746 struct xformsw *xsp;
1747
1748 if (sav->tdb_xform != NULL) /* Previously initialized. */
1749 return (0);
1750 for (xsp = xforms; xsp; xsp = xsp->xf_next)
1751 if (xsp->xf_type == xftype)
1752 return ((*xsp->xf_init)(sav, xsp));
1753 return (EINVAL);
1754 }
Cache object: 622941626c00641770579dd583d6b476
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