FreeBSD/Linux Kernel Cross Reference
sys/netipsec/ipsec.c
1 /* $FreeBSD: releng/10.1/sys/netipsec/ipsec.c 264814 2014-04-23 11:22:54Z 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 v = ip->ip_v;
563 switch (v) {
564 case 4:
565 error = ipsec4_setspidx_ipaddr(m, spidx);
566 if (error)
567 return (error);
568 ipsec4_get_ulp(m, spidx, needport);
569 return (0);
570 #ifdef INET6
571 case 6:
572 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) {
573 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
574 printf("%s: pkthdr len(%d) too small (v6), "
575 "ignored\n", __func__, m->m_pkthdr.len));
576 return (EINVAL);
577 }
578 error = ipsec6_setspidx_ipaddr(m, spidx);
579 if (error)
580 return (error);
581 ipsec6_get_ulp(m, spidx, needport);
582 return (0);
583 #endif
584 default:
585 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
586 printf("%s: " "unknown IP version %u, ignored.\n",
587 __func__, v));
588 return (EINVAL);
589 }
590 }
591
592 static void
593 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
594 {
595 u_int8_t nxt;
596 int off;
597
598 /* Sanity check. */
599 IPSEC_ASSERT(m != NULL, ("null mbuf"));
600 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short"));
601
602 if (m->m_len >= sizeof (struct ip)) {
603 struct ip *ip = mtod(m, struct ip *);
604 if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
605 goto done;
606 off = ip->ip_hl << 2;
607 nxt = ip->ip_p;
608 } else {
609 struct ip ih;
610
611 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih);
612 if (ih.ip_off & htons(IP_MF | IP_OFFMASK))
613 goto done;
614 off = ih.ip_hl << 2;
615 nxt = ih.ip_p;
616 }
617
618 while (off < m->m_pkthdr.len) {
619 struct ip6_ext ip6e;
620 struct tcphdr th;
621 struct udphdr uh;
622
623 switch (nxt) {
624 case IPPROTO_TCP:
625 spidx->ul_proto = nxt;
626 if (!needport)
627 goto done_proto;
628 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
629 goto done;
630 m_copydata(m, off, sizeof (th), (caddr_t) &th);
631 spidx->src.sin.sin_port = th.th_sport;
632 spidx->dst.sin.sin_port = th.th_dport;
633 return;
634 case IPPROTO_UDP:
635 spidx->ul_proto = nxt;
636 if (!needport)
637 goto done_proto;
638 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
639 goto done;
640 m_copydata(m, off, sizeof (uh), (caddr_t) &uh);
641 spidx->src.sin.sin_port = uh.uh_sport;
642 spidx->dst.sin.sin_port = uh.uh_dport;
643 return;
644 case IPPROTO_AH:
645 if (off + sizeof(ip6e) > m->m_pkthdr.len)
646 goto done;
647 /* XXX Sigh, this works but is totally bogus. */
648 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e);
649 off += (ip6e.ip6e_len + 2) << 2;
650 nxt = ip6e.ip6e_nxt;
651 break;
652 case IPPROTO_ICMP:
653 default:
654 /* XXX Intermediate headers??? */
655 spidx->ul_proto = nxt;
656 goto done_proto;
657 }
658 }
659 done:
660 spidx->ul_proto = IPSEC_ULPROTO_ANY;
661 done_proto:
662 spidx->src.sin.sin_port = IPSEC_PORT_ANY;
663 spidx->dst.sin.sin_port = IPSEC_PORT_ANY;
664 }
665
666 /* Assumes that m is sane. */
667 static int
668 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
669 {
670 static const struct sockaddr_in template = {
671 sizeof (struct sockaddr_in),
672 AF_INET,
673 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 }
674 };
675
676 spidx->src.sin = template;
677 spidx->dst.sin = template;
678
679 if (m->m_len < sizeof (struct ip)) {
680 m_copydata(m, offsetof(struct ip, ip_src),
681 sizeof (struct in_addr),
682 (caddr_t) &spidx->src.sin.sin_addr);
683 m_copydata(m, offsetof(struct ip, ip_dst),
684 sizeof (struct in_addr),
685 (caddr_t) &spidx->dst.sin.sin_addr);
686 } else {
687 struct ip *ip = mtod(m, struct ip *);
688 spidx->src.sin.sin_addr = ip->ip_src;
689 spidx->dst.sin.sin_addr = ip->ip_dst;
690 }
691
692 spidx->prefs = sizeof(struct in_addr) << 3;
693 spidx->prefd = sizeof(struct in_addr) << 3;
694
695 return (0);
696 }
697
698 #ifdef INET6
699 static void
700 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
701 {
702 int off, nxt;
703 struct tcphdr th;
704 struct udphdr uh;
705 struct icmp6_hdr ih;
706
707 /* Sanity check. */
708 if (m == NULL)
709 panic("%s: NULL pointer was passed.\n", __func__);
710
711 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
712 printf("%s:\n", __func__); kdebug_mbuf(m));
713
714 /* Set default. */
715 spidx->ul_proto = IPSEC_ULPROTO_ANY;
716 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY;
717 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY;
718
719 nxt = -1;
720 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
721 if (off < 0 || m->m_pkthdr.len < off)
722 return;
723
724 switch (nxt) {
725 case IPPROTO_TCP:
726 spidx->ul_proto = nxt;
727 if (!needport)
728 break;
729 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
730 break;
731 m_copydata(m, off, sizeof(th), (caddr_t)&th);
732 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport;
733 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport;
734 break;
735 case IPPROTO_UDP:
736 spidx->ul_proto = nxt;
737 if (!needport)
738 break;
739 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
740 break;
741 m_copydata(m, off, sizeof(uh), (caddr_t)&uh);
742 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport;
743 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport;
744 break;
745 case IPPROTO_ICMPV6:
746 spidx->ul_proto = nxt;
747 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len)
748 break;
749 m_copydata(m, off, sizeof(ih), (caddr_t)&ih);
750 ((struct sockaddr_in6 *)&spidx->src)->sin6_port =
751 htons((uint16_t)ih.icmp6_type);
752 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port =
753 htons((uint16_t)ih.icmp6_code);
754 break;
755 default:
756 /* XXX Intermediate headers??? */
757 spidx->ul_proto = nxt;
758 break;
759 }
760 }
761
762 /* Assumes that m is sane. */
763 static int
764 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
765 {
766 struct ip6_hdr *ip6 = NULL;
767 struct ip6_hdr ip6buf;
768 struct sockaddr_in6 *sin6;
769
770 if (m->m_len >= sizeof(*ip6))
771 ip6 = mtod(m, struct ip6_hdr *);
772 else {
773 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf);
774 ip6 = &ip6buf;
775 }
776
777 sin6 = (struct sockaddr_in6 *)&spidx->src;
778 bzero(sin6, sizeof(*sin6));
779 sin6->sin6_family = AF_INET6;
780 sin6->sin6_len = sizeof(struct sockaddr_in6);
781 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src));
782 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
783 sin6->sin6_addr.s6_addr16[1] = 0;
784 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]);
785 }
786 spidx->prefs = sizeof(struct in6_addr) << 3;
787
788 sin6 = (struct sockaddr_in6 *)&spidx->dst;
789 bzero(sin6, sizeof(*sin6));
790 sin6->sin6_family = AF_INET6;
791 sin6->sin6_len = sizeof(struct sockaddr_in6);
792 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst));
793 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
794 sin6->sin6_addr.s6_addr16[1] = 0;
795 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
796 }
797 spidx->prefd = sizeof(struct in6_addr) << 3;
798
799 return (0);
800 }
801 #endif
802
803 static void
804 ipsec_delpcbpolicy(struct inpcbpolicy *p)
805 {
806
807 free(p, M_IPSEC_INPCB);
808 }
809
810 /* Initialize policy in PCB. */
811 int
812 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp)
813 {
814 struct inpcbpolicy *new;
815
816 /* Sanity check. */
817 if (so == NULL || pcb_sp == NULL)
818 panic("%s: NULL pointer was passed.\n", __func__);
819
820 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy),
821 M_IPSEC_INPCB, M_NOWAIT|M_ZERO);
822 if (new == NULL) {
823 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
824 return (ENOBUFS);
825 }
826
827 new->priv = IPSEC_IS_PRIVILEGED_SO(so);
828
829 if ((new->sp_in = KEY_NEWSP()) == NULL) {
830 ipsec_delpcbpolicy(new);
831 return (ENOBUFS);
832 }
833 new->sp_in->state = IPSEC_SPSTATE_ALIVE;
834 new->sp_in->policy = IPSEC_POLICY_ENTRUST;
835
836 if ((new->sp_out = KEY_NEWSP()) == NULL) {
837 KEY_FREESP(&new->sp_in);
838 ipsec_delpcbpolicy(new);
839 return (ENOBUFS);
840 }
841 new->sp_out->state = IPSEC_SPSTATE_ALIVE;
842 new->sp_out->policy = IPSEC_POLICY_ENTRUST;
843
844 *pcb_sp = new;
845
846 return (0);
847 }
848
849 /* Copy old IPsec policy into new. */
850 int
851 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new)
852 {
853 struct secpolicy *sp;
854
855 sp = ipsec_deepcopy_policy(old->sp_in);
856 if (sp) {
857 KEY_FREESP(&new->sp_in);
858 new->sp_in = sp;
859 } else
860 return (ENOBUFS);
861
862 sp = ipsec_deepcopy_policy(old->sp_out);
863 if (sp) {
864 KEY_FREESP(&new->sp_out);
865 new->sp_out = sp;
866 } else
867 return (ENOBUFS);
868
869 new->priv = old->priv;
870
871 return (0);
872 }
873
874 struct ipsecrequest *
875 ipsec_newisr(void)
876 {
877 struct ipsecrequest *p;
878
879 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO);
880 if (p != NULL)
881 IPSECREQUEST_LOCK_INIT(p);
882 return (p);
883 }
884
885 void
886 ipsec_delisr(struct ipsecrequest *p)
887 {
888
889 IPSECREQUEST_LOCK_DESTROY(p);
890 free(p, M_IPSEC_SR);
891 }
892
893 /* Deep-copy a policy in PCB. */
894 static struct secpolicy *
895 ipsec_deepcopy_policy(struct secpolicy *src)
896 {
897 struct ipsecrequest *newchain = NULL;
898 struct ipsecrequest *p;
899 struct ipsecrequest **q;
900 struct ipsecrequest *r;
901 struct secpolicy *dst;
902
903 if (src == NULL)
904 return (NULL);
905 dst = KEY_NEWSP();
906 if (dst == NULL)
907 return (NULL);
908
909 /*
910 * Deep-copy IPsec request chain. This is required since struct
911 * ipsecrequest is not reference counted.
912 */
913 q = &newchain;
914 for (p = src->req; p; p = p->next) {
915 *q = ipsec_newisr();
916 if (*q == NULL)
917 goto fail;
918 (*q)->saidx.proto = p->saidx.proto;
919 (*q)->saidx.mode = p->saidx.mode;
920 (*q)->level = p->level;
921 (*q)->saidx.reqid = p->saidx.reqid;
922
923 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src));
924 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst));
925
926 (*q)->sp = dst;
927
928 q = &((*q)->next);
929 }
930
931 dst->req = newchain;
932 dst->state = src->state;
933 dst->policy = src->policy;
934 /* Do not touch the refcnt fields. */
935
936 return (dst);
937
938 fail:
939 for (p = newchain; p; p = r) {
940 r = p->next;
941 ipsec_delisr(p);
942 p = NULL;
943 }
944 return (NULL);
945 }
946
947 /* Set policy and IPsec request if present. */
948 static int
949 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname,
950 caddr_t request, size_t len, struct ucred *cred)
951 {
952 struct sadb_x_policy *xpl;
953 struct secpolicy *newsp = NULL;
954 int error;
955
956 /* Sanity check. */
957 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL)
958 return (EINVAL);
959 if (len < sizeof(*xpl))
960 return (EINVAL);
961 xpl = (struct sadb_x_policy *)request;
962
963 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
964 printf("%s: passed policy\n", __func__);
965 kdebug_sadb_x_policy((struct sadb_ext *)xpl));
966
967 /* Check policy type. */
968 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */
969 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD
970 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE)
971 return (EINVAL);
972
973 /* Check privileged socket. */
974 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) {
975 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0);
976 if (error)
977 return (EACCES);
978 }
979
980 /* Allocating new SP entry. */
981 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL)
982 return (error);
983
984 newsp->state = IPSEC_SPSTATE_ALIVE;
985
986 /* Clear old SP and set new SP. */
987 KEY_FREESP(pcb_sp);
988 *pcb_sp = newsp;
989 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
990 printf("%s: new policy\n", __func__);
991 kdebug_secpolicy(newsp));
992
993 return (0);
994 }
995
996 int
997 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request,
998 size_t len, struct ucred *cred)
999 {
1000 struct sadb_x_policy *xpl;
1001 struct secpolicy **pcb_sp;
1002
1003 /* Sanity check. */
1004 if (inp == NULL || request == NULL)
1005 return (EINVAL);
1006 if (len < sizeof(*xpl))
1007 return (EINVAL);
1008 xpl = (struct sadb_x_policy *)request;
1009
1010 /* Select direction. */
1011 switch (xpl->sadb_x_policy_dir) {
1012 case IPSEC_DIR_INBOUND:
1013 pcb_sp = &inp->inp_sp->sp_in;
1014 break;
1015 case IPSEC_DIR_OUTBOUND:
1016 pcb_sp = &inp->inp_sp->sp_out;
1017 break;
1018 default:
1019 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1020 xpl->sadb_x_policy_dir));
1021 return (EINVAL);
1022 }
1023
1024 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred));
1025 }
1026
1027 int
1028 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len,
1029 struct mbuf **mp)
1030 {
1031 struct sadb_x_policy *xpl;
1032 struct secpolicy *pcb_sp;
1033
1034 /* Sanity check. */
1035 if (inp == NULL || request == NULL || mp == NULL)
1036 return (EINVAL);
1037 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
1038 if (len < sizeof(*xpl))
1039 return (EINVAL);
1040 xpl = (struct sadb_x_policy *)request;
1041
1042 /* Select direction. */
1043 switch (xpl->sadb_x_policy_dir) {
1044 case IPSEC_DIR_INBOUND:
1045 pcb_sp = inp->inp_sp->sp_in;
1046 break;
1047 case IPSEC_DIR_OUTBOUND:
1048 pcb_sp = inp->inp_sp->sp_out;
1049 break;
1050 default:
1051 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1052 xpl->sadb_x_policy_dir));
1053 return (EINVAL);
1054 }
1055
1056 /* Sanity check. Should be an IPSEC_ASSERT. */
1057 if (pcb_sp == NULL)
1058 return (EINVAL);
1059
1060 *mp = key_sp2msg(pcb_sp);
1061 if (!*mp) {
1062 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
1063 return (ENOBUFS);
1064 }
1065
1066 (*mp)->m_type = MT_DATA;
1067 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1068 printf("%s:\n", __func__); kdebug_mbuf(*mp));
1069
1070 return (0);
1071 }
1072
1073 /* Delete policy in PCB. */
1074 int
1075 ipsec_delete_pcbpolicy(struct inpcb *inp)
1076 {
1077 IPSEC_ASSERT(inp != NULL, ("null inp"));
1078
1079 if (inp->inp_sp == NULL)
1080 return (0);
1081
1082 if (inp->inp_sp->sp_in != NULL)
1083 KEY_FREESP(&inp->inp_sp->sp_in);
1084
1085 if (inp->inp_sp->sp_out != NULL)
1086 KEY_FREESP(&inp->inp_sp->sp_out);
1087
1088 ipsec_delpcbpolicy(inp->inp_sp);
1089 inp->inp_sp = NULL;
1090
1091 return (0);
1092 }
1093
1094 /*
1095 * Return current level.
1096 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned.
1097 */
1098 u_int
1099 ipsec_get_reqlevel(struct ipsecrequest *isr)
1100 {
1101 u_int level = 0;
1102 u_int esp_trans_deflev, esp_net_deflev;
1103 u_int ah_trans_deflev, ah_net_deflev;
1104
1105 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument"));
1106 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family,
1107 ("af family mismatch, src %u, dst %u",
1108 isr->sp->spidx.src.sa.sa_family,
1109 isr->sp->spidx.dst.sa.sa_family));
1110
1111 /* XXX Note that we have ipseclog() expanded here - code sync issue. */
1112 #define IPSEC_CHECK_DEFAULT(lev) \
1113 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \
1114 && (lev) != IPSEC_LEVEL_UNIQUE) \
1115 ? (V_ipsec_debug \
1116 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\
1117 (lev), IPSEC_LEVEL_REQUIRE) \
1118 : 0), \
1119 (lev) = IPSEC_LEVEL_REQUIRE, \
1120 (lev) \
1121 : (lev))
1122
1123 /* Set default level. */
1124 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) {
1125 #ifdef INET
1126 case AF_INET:
1127 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev);
1128 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev);
1129 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev);
1130 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev);
1131 break;
1132 #endif
1133 #ifdef INET6
1134 case AF_INET6:
1135 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev);
1136 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev);
1137 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev);
1138 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev);
1139 break;
1140 #endif /* INET6 */
1141 default:
1142 panic("%s: unknown af %u",
1143 __func__, isr->sp->spidx.src.sa.sa_family);
1144 }
1145
1146 #undef IPSEC_CHECK_DEFAULT
1147
1148 /* Set level. */
1149 switch (isr->level) {
1150 case IPSEC_LEVEL_DEFAULT:
1151 switch (isr->saidx.proto) {
1152 case IPPROTO_ESP:
1153 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1154 level = esp_net_deflev;
1155 else
1156 level = esp_trans_deflev;
1157 break;
1158 case IPPROTO_AH:
1159 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1160 level = ah_net_deflev;
1161 else
1162 level = ah_trans_deflev;
1163 break;
1164 case IPPROTO_IPCOMP:
1165 /*
1166 * We don't really care, as IPcomp document says that
1167 * we shouldn't compress small packets.
1168 */
1169 level = IPSEC_LEVEL_USE;
1170 break;
1171 default:
1172 panic("%s: Illegal protocol defined %u\n", __func__,
1173 isr->saidx.proto);
1174 }
1175 break;
1176
1177 case IPSEC_LEVEL_USE:
1178 case IPSEC_LEVEL_REQUIRE:
1179 level = isr->level;
1180 break;
1181 case IPSEC_LEVEL_UNIQUE:
1182 level = IPSEC_LEVEL_REQUIRE;
1183 break;
1184
1185 default:
1186 panic("%s: Illegal IPsec level %u\n", __func__, isr->level);
1187 }
1188
1189 return (level);
1190 }
1191
1192 /*
1193 * Check security policy requirements against the actual
1194 * packet contents. Return one if the packet should be
1195 * reject as "invalid"; otherwiser return zero to have the
1196 * packet treated as "valid".
1197 *
1198 * OUT:
1199 * 0: valid
1200 * 1: invalid
1201 */
1202 int
1203 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m)
1204 {
1205 struct ipsecrequest *isr;
1206 int need_auth;
1207
1208 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1209 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1210
1211 /* Check policy. */
1212 switch (sp->policy) {
1213 case IPSEC_POLICY_DISCARD:
1214 return (1);
1215 case IPSEC_POLICY_BYPASS:
1216 case IPSEC_POLICY_NONE:
1217 return (0);
1218 }
1219
1220 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1221 ("invalid policy %u", sp->policy));
1222
1223 /* XXX Should compare policy against IPsec header history. */
1224
1225 need_auth = 0;
1226 for (isr = sp->req; isr != NULL; isr = isr->next) {
1227 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE)
1228 continue;
1229 switch (isr->saidx.proto) {
1230 case IPPROTO_ESP:
1231 if ((m->m_flags & M_DECRYPTED) == 0) {
1232 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1233 printf("%s: ESP m_flags:%x\n", __func__,
1234 m->m_flags));
1235 return (1);
1236 }
1237
1238 if (!need_auth &&
1239 isr->sav != NULL &&
1240 isr->sav->tdb_authalgxform != NULL &&
1241 (m->m_flags & M_AUTHIPDGM) == 0) {
1242 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1243 printf("%s: ESP/AH m_flags:%x\n", __func__,
1244 m->m_flags));
1245 return (1);
1246 }
1247 break;
1248 case IPPROTO_AH:
1249 need_auth = 1;
1250 if ((m->m_flags & M_AUTHIPHDR) == 0) {
1251 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1252 printf("%s: AH m_flags:%x\n", __func__,
1253 m->m_flags));
1254 return (1);
1255 }
1256 break;
1257 case IPPROTO_IPCOMP:
1258 /*
1259 * We don't really care, as IPcomp document
1260 * says that we shouldn't compress small
1261 * packets. IPComp policy should always be
1262 * treated as being in "use" level.
1263 */
1264 break;
1265 }
1266 }
1267 return (0); /* Valid. */
1268 }
1269
1270 static int
1271 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp)
1272 {
1273 struct secpolicy *sp;
1274 int error;
1275 int result;
1276
1277 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1278
1279 /*
1280 * Get SP for this packet.
1281 * When we are called from ip_forward(), we call
1282 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1283 */
1284 if (inp == NULL)
1285 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error);
1286 else
1287 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error);
1288
1289 if (sp != NULL) {
1290 result = ipsec_in_reject(sp, m);
1291 KEY_FREESP(&sp);
1292 } else {
1293 result = 0; /* XXX Should be panic?
1294 * -> No, there may be error. */
1295 }
1296 return (result);
1297 }
1298
1299 /*
1300 * Check AH/ESP integrity.
1301 * This function is called from tcp_input(), udp_input(),
1302 * and {ah,esp}4_input for tunnel mode.
1303 */
1304 int
1305 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp)
1306 {
1307 int result;
1308
1309 result = ipsec46_in_reject(m, inp);
1310 if (result)
1311 IPSECSTAT_INC(ips_in_polvio);
1312
1313 return (result);
1314 }
1315
1316 #ifdef INET6
1317 /*
1318 * Check AH/ESP integrity.
1319 * This function is called from tcp6_input(), udp6_input(),
1320 * and {ah,esp}6_input for tunnel mode.
1321 */
1322 int
1323 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp)
1324 {
1325 int result;
1326
1327 result = ipsec46_in_reject(m, inp);
1328 if (result)
1329 IPSEC6STAT_INC(ips_in_polvio);
1330
1331 return (result);
1332 }
1333 #endif
1334
1335 /*
1336 * Compute the byte size to be occupied by IPsec header.
1337 * In case it is tunnelled, it includes the size of outer IP header.
1338 * NOTE: SP passed is freed in this function.
1339 */
1340 static size_t
1341 ipsec_hdrsiz_internal(struct secpolicy *sp)
1342 {
1343 struct ipsecrequest *isr;
1344 size_t size;
1345
1346 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1347 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1348
1349 switch (sp->policy) {
1350 case IPSEC_POLICY_DISCARD:
1351 case IPSEC_POLICY_BYPASS:
1352 case IPSEC_POLICY_NONE:
1353 return (0);
1354 }
1355
1356 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1357 ("invalid policy %u", sp->policy));
1358
1359 size = 0;
1360 for (isr = sp->req; isr != NULL; isr = isr->next) {
1361 size_t clen = 0;
1362
1363 switch (isr->saidx.proto) {
1364 case IPPROTO_ESP:
1365 clen = esp_hdrsiz(isr->sav);
1366 break;
1367 case IPPROTO_AH:
1368 clen = ah_hdrsiz(isr->sav);
1369 break;
1370 case IPPROTO_IPCOMP:
1371 clen = sizeof(struct ipcomp);
1372 break;
1373 }
1374
1375 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
1376 switch (isr->saidx.dst.sa.sa_family) {
1377 case AF_INET:
1378 clen += sizeof(struct ip);
1379 break;
1380 #ifdef INET6
1381 case AF_INET6:
1382 clen += sizeof(struct ip6_hdr);
1383 break;
1384 #endif
1385 default:
1386 ipseclog((LOG_ERR, "%s: unknown AF %d in "
1387 "IPsec tunnel SA\n", __func__,
1388 ((struct sockaddr *)&isr->saidx.dst)->sa_family));
1389 break;
1390 }
1391 }
1392 size += clen;
1393 }
1394
1395 return (size);
1396 }
1397
1398 /*
1399 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(),
1400 * disabled ip6_ipsec_mtu() and ip6_forward().
1401 */
1402 size_t
1403 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp)
1404 {
1405 struct secpolicy *sp;
1406 int error;
1407 size_t size;
1408
1409 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1410
1411 /* Get SP for this packet.
1412 * When we are called from ip_forward(), we call
1413 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1414 */
1415 if (inp == NULL)
1416 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error);
1417 else
1418 sp = ipsec_getpolicybysock(m, dir, inp, &error);
1419
1420 if (sp != NULL) {
1421 size = ipsec_hdrsiz_internal(sp);
1422 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1423 printf("%s: size:%lu.\n", __func__,
1424 (unsigned long)size));
1425
1426 KEY_FREESP(&sp);
1427 } else {
1428 size = 0; /* XXX Should be panic?
1429 * -> No, we are called w/o knowing if
1430 * IPsec processing is needed. */
1431 }
1432 return (size);
1433 }
1434
1435 /*
1436 * Check the variable replay window.
1437 * ipsec_chkreplay() performs replay check before ICV verification.
1438 * ipsec_updatereplay() updates replay bitmap. This must be called after
1439 * ICV verification (it also performs replay check, which is usually done
1440 * beforehand).
1441 * 0 (zero) is returned if packet disallowed, 1 if packet permitted.
1442 *
1443 * Based on RFC 2401.
1444 */
1445 int
1446 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav)
1447 {
1448 const struct secreplay *replay;
1449 u_int32_t diff;
1450 int fr;
1451 u_int32_t wsizeb; /* Constant: bits of window size. */
1452 int frlast; /* Constant: last frame. */
1453
1454 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1455 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1456
1457 replay = sav->replay;
1458
1459 if (replay->wsize == 0)
1460 return (1); /* No need to check replay. */
1461
1462 /* Constant. */
1463 frlast = replay->wsize - 1;
1464 wsizeb = replay->wsize << 3;
1465
1466 /* Sequence number of 0 is invalid. */
1467 if (seq == 0)
1468 return (0);
1469
1470 /* First time is always okay. */
1471 if (replay->count == 0)
1472 return (1);
1473
1474 if (seq > replay->lastseq) {
1475 /* Larger sequences are okay. */
1476 return (1);
1477 } else {
1478 /* seq is equal or less than lastseq. */
1479 diff = replay->lastseq - seq;
1480
1481 /* Over range to check, i.e. too old or wrapped. */
1482 if (diff >= wsizeb)
1483 return (0);
1484
1485 fr = frlast - diff / 8;
1486
1487 /* This packet already seen? */
1488 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1489 return (0);
1490
1491 /* Out of order but good. */
1492 return (1);
1493 }
1494 }
1495
1496 /*
1497 * Check replay counter whether to update or not.
1498 * OUT: 0: OK
1499 * 1: NG
1500 */
1501 int
1502 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav)
1503 {
1504 struct secreplay *replay;
1505 u_int32_t diff;
1506 int fr;
1507 u_int32_t wsizeb; /* Constant: bits of window size. */
1508 int frlast; /* Constant: last frame. */
1509
1510 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1511 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1512
1513 replay = sav->replay;
1514
1515 if (replay->wsize == 0)
1516 goto ok; /* No need to check replay. */
1517
1518 /* Constant. */
1519 frlast = replay->wsize - 1;
1520 wsizeb = replay->wsize << 3;
1521
1522 /* Sequence number of 0 is invalid. */
1523 if (seq == 0)
1524 return (1);
1525
1526 /* First time. */
1527 if (replay->count == 0) {
1528 replay->lastseq = seq;
1529 bzero(replay->bitmap, replay->wsize);
1530 (replay->bitmap)[frlast] = 1;
1531 goto ok;
1532 }
1533
1534 if (seq > replay->lastseq) {
1535 /* seq is larger than lastseq. */
1536 diff = seq - replay->lastseq;
1537
1538 /* New larger sequence number. */
1539 if (diff < wsizeb) {
1540 /* In window. */
1541 /* Set bit for this packet. */
1542 vshiftl(replay->bitmap, diff, replay->wsize);
1543 (replay->bitmap)[frlast] |= 1;
1544 } else {
1545 /* This packet has a "way larger". */
1546 bzero(replay->bitmap, replay->wsize);
1547 (replay->bitmap)[frlast] = 1;
1548 }
1549 replay->lastseq = seq;
1550
1551 /* Larger is good. */
1552 } else {
1553 /* seq is equal or less than lastseq. */
1554 diff = replay->lastseq - seq;
1555
1556 /* Over range to check, i.e. too old or wrapped. */
1557 if (diff >= wsizeb)
1558 return (1);
1559
1560 fr = frlast - diff / 8;
1561
1562 /* This packet already seen? */
1563 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1564 return (1);
1565
1566 /* Mark as seen. */
1567 (replay->bitmap)[fr] |= (1 << (diff % 8));
1568
1569 /* Out of order but good. */
1570 }
1571
1572 ok:
1573 if (replay->count == ~0) {
1574
1575 /* Set overflow flag. */
1576 replay->overflow++;
1577
1578 /* Don't increment, no more packets accepted. */
1579 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0)
1580 return (1);
1581
1582 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n",
1583 __func__, replay->overflow, ipsec_logsastr(sav)));
1584 }
1585
1586 replay->count++;
1587
1588 return (0);
1589 }
1590
1591 /*
1592 * Shift variable length buffer to left.
1593 * IN: bitmap: pointer to the buffer
1594 * nbit: the number of to shift.
1595 * wsize: buffer size (bytes).
1596 */
1597 static void
1598 vshiftl(unsigned char *bitmap, int nbit, int wsize)
1599 {
1600 int s, j, i;
1601 unsigned char over;
1602
1603 for (j = 0; j < nbit; j += 8) {
1604 s = (nbit - j < 8) ? (nbit - j): 8;
1605 bitmap[0] <<= s;
1606 for (i = 1; i < wsize; i++) {
1607 over = (bitmap[i] >> (8 - s));
1608 bitmap[i] <<= s;
1609 bitmap[i-1] |= over;
1610 }
1611 }
1612 }
1613
1614 #ifdef INET
1615 /* Return a printable string for the IPv4 address. */
1616 static char *
1617 inet_ntoa4(struct in_addr ina)
1618 {
1619 static char buf[4][4 * sizeof "123" + 4];
1620 unsigned char *ucp = (unsigned char *) &ina;
1621 static int i = 3;
1622
1623 /* XXX-BZ Returns static buffer. */
1624 i = (i + 1) % 4;
1625 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff,
1626 ucp[2] & 0xff, ucp[3] & 0xff);
1627 return (buf[i]);
1628 }
1629 #endif
1630
1631 /* Return a printable string for the address. */
1632 char *
1633 ipsec_address(union sockaddr_union* sa)
1634 {
1635 #ifdef INET6
1636 char ip6buf[INET6_ADDRSTRLEN];
1637 #endif
1638
1639 switch (sa->sa.sa_family) {
1640 #ifdef INET
1641 case AF_INET:
1642 return (inet_ntoa4(sa->sin.sin_addr));
1643 #endif /* INET */
1644 #ifdef INET6
1645 case AF_INET6:
1646 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr));
1647 #endif /* INET6 */
1648 default:
1649 return ("(unknown address family)");
1650 }
1651 }
1652
1653 const char *
1654 ipsec_logsastr(struct secasvar *sav)
1655 {
1656 static char buf[256];
1657 char *p;
1658 struct secasindex *saidx = &sav->sah->saidx;
1659
1660 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family,
1661 ("address family mismatch"));
1662
1663 p = buf;
1664 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi));
1665 while (p && *p)
1666 p++;
1667 /* NB: only use ipsec_address on one address at a time. */
1668 snprintf(p, sizeof (buf) - (p - buf), "src=%s ",
1669 ipsec_address(&saidx->src));
1670 while (p && *p)
1671 p++;
1672 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)",
1673 ipsec_address(&saidx->dst));
1674
1675 return (buf);
1676 }
1677
1678 void
1679 ipsec_dumpmbuf(struct mbuf *m)
1680 {
1681 int totlen;
1682 int i;
1683 u_char *p;
1684
1685 totlen = 0;
1686 printf("---\n");
1687 while (m) {
1688 p = mtod(m, u_char *);
1689 for (i = 0; i < m->m_len; i++) {
1690 printf("%02x ", p[i]);
1691 totlen++;
1692 if (totlen % 16 == 0)
1693 printf("\n");
1694 }
1695 m = m->m_next;
1696 }
1697 if (totlen % 16 != 0)
1698 printf("\n");
1699 printf("---\n");
1700 }
1701
1702 static void
1703 ipsec_init(const void *unused __unused)
1704 {
1705
1706 SECPOLICY_LOCK_INIT(&V_ip4_def_policy);
1707 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */
1708 }
1709 VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init,
1710 NULL);
1711
1712
1713 /* XXX This stuff doesn't belong here... */
1714
1715 static struct xformsw* xforms = NULL;
1716
1717 /*
1718 * Register a transform; typically at system startup.
1719 */
1720 void
1721 xform_register(struct xformsw* xsp)
1722 {
1723
1724 xsp->xf_next = xforms;
1725 xforms = xsp;
1726 }
1727
1728 /*
1729 * Initialize transform support in an sav.
1730 */
1731 int
1732 xform_init(struct secasvar *sav, int xftype)
1733 {
1734 struct xformsw *xsp;
1735
1736 if (sav->tdb_xform != NULL) /* Previously initialized. */
1737 return (0);
1738 for (xsp = xforms; xsp; xsp = xsp->xf_next)
1739 if (xsp->xf_type == xftype)
1740 return ((*xsp->xf_init)(sav, xsp));
1741 return (EINVAL);
1742 }
Cache object: 73e4099b793676d06dec003f623888bc
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