FreeBSD/Linux Kernel Cross Reference
sys/netipsec/ipsec.c
1 /* $FreeBSD$ */
2 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */
3
4 /*-
5 * SPDX-License-Identifier: BSD-3-Clause
6 *
7 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the project nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 /*
36 * IPsec controller part.
37 */
38
39 #include "opt_inet.h"
40 #include "opt_inet6.h"
41 #include "opt_ipsec.h"
42
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/malloc.h>
46 #include <sys/mbuf.h>
47 #include <sys/domain.h>
48 #include <sys/priv.h>
49 #include <sys/protosw.h>
50 #include <sys/socket.h>
51 #include <sys/socketvar.h>
52 #include <sys/errno.h>
53 #include <sys/hhook.h>
54 #include <sys/time.h>
55 #include <sys/kernel.h>
56 #include <sys/syslog.h>
57 #include <sys/sysctl.h>
58 #include <sys/proc.h>
59
60 #include <net/if.h>
61 #include <net/if_enc.h>
62 #include <net/if_var.h>
63 #include <net/vnet.h>
64
65 #include <netinet/in.h>
66 #include <netinet/in_systm.h>
67 #include <netinet/ip.h>
68 #include <netinet/ip_var.h>
69 #include <netinet/in_var.h>
70 #include <netinet/udp.h>
71 #include <netinet/udp_var.h>
72 #include <netinet/tcp.h>
73 #include <netinet/udp.h>
74
75 #include <netinet/ip6.h>
76 #ifdef INET6
77 #include <netinet6/ip6_var.h>
78 #endif
79 #include <netinet/in_pcb.h>
80 #ifdef INET6
81 #include <netinet/icmp6.h>
82 #endif
83
84 #include <sys/types.h>
85 #include <netipsec/ipsec.h>
86 #ifdef INET6
87 #include <netipsec/ipsec6.h>
88 #endif
89 #include <netipsec/ah_var.h>
90 #include <netipsec/esp_var.h>
91 #include <netipsec/ipcomp.h> /*XXX*/
92 #include <netipsec/ipcomp_var.h>
93 #include <netipsec/ipsec_support.h>
94
95 #include <netipsec/key.h>
96 #include <netipsec/keydb.h>
97 #include <netipsec/key_debug.h>
98
99 #include <netipsec/xform.h>
100
101 #include <machine/in_cksum.h>
102
103 #include <opencrypto/cryptodev.h>
104
105 /* NB: name changed so netstat doesn't use it. */
106 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat);
107 VNET_PCPUSTAT_SYSINIT(ipsec4stat);
108
109 #ifdef VIMAGE
110 VNET_PCPUSTAT_SYSUNINIT(ipsec4stat);
111 #endif /* VIMAGE */
112
113 /* DF bit on encap. 0: clear 1: set 2: copy */
114 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0;
115 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE;
116 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE;
117 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE;
118 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE;
119 /* ECN ignore(-1)/forbidden(0)/allowed(1) */
120 VNET_DEFINE(int, ip4_ipsec_ecn) = 0;
121
122 VNET_DEFINE_STATIC(int, ip4_filtertunnel) = 0;
123 #define V_ip4_filtertunnel VNET(ip4_filtertunnel)
124 VNET_DEFINE_STATIC(int, check_policy_history) = 0;
125 #define V_check_policy_history VNET(check_policy_history)
126 VNET_DEFINE_STATIC(struct secpolicy *, def_policy) = NULL;
127 #define V_def_policy VNET(def_policy)
128 static int
129 sysctl_def_policy(SYSCTL_HANDLER_ARGS)
130 {
131 int error, value;
132
133 value = V_def_policy->policy;
134 error = sysctl_handle_int(oidp, &value, 0, req);
135 if (error == 0) {
136 if (value != IPSEC_POLICY_DISCARD &&
137 value != IPSEC_POLICY_NONE)
138 return (EINVAL);
139 V_def_policy->policy = value;
140 }
141 return (error);
142 }
143
144 /*
145 * Crypto support requirements:
146 *
147 * 1 require hardware support
148 * -1 require software support
149 * 0 take anything
150 */
151 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE;
152
153 /*
154 * Use asynchronous mode to parallelize crypto jobs:
155 *
156 * 0 - disabled
157 * 1 - enabled
158 */
159 VNET_DEFINE(int, async_crypto) = 0;
160
161 /*
162 * TCP/UDP checksum handling policy for transport mode NAT-T (RFC3948)
163 *
164 * 0 - auto: incrementally recompute, when checksum delta is known;
165 * if checksum delta isn't known, reset checksum to zero for UDP,
166 * and mark csum_flags as valid for TCP.
167 * 1 - fully recompute TCP/UDP checksum.
168 */
169 VNET_DEFINE(int, natt_cksum_policy) = 0;
170
171 FEATURE(ipsec, "Internet Protocol Security (IPsec)");
172 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')");
173
174 SYSCTL_DECL(_net_inet_ipsec);
175
176 /* net.inet.ipsec */
177 SYSCTL_PROC(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy,
178 CTLTYPE_INT | CTLFLAG_VNET | CTLFLAG_RW, 0, 0, sysctl_def_policy, "I",
179 "IPsec default policy.");
180 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
181 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0,
182 "Default ESP transport mode level");
183 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
184 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0,
185 "Default ESP tunnel mode level.");
186 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
187 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0,
188 "AH transfer mode default level.");
189 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
190 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0,
191 "AH tunnel mode default level.");
192 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos,
193 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0,
194 "If set, clear type-of-service field when doing AH computation.");
195 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit,
196 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0,
197 "Do not fragment bit on encap.");
198 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn,
199 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0,
200 "Explicit Congestion Notification handling.");
201 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, crypto_support,
202 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(crypto_support), 0,
203 "Crypto driver selection.");
204 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, async_crypto,
205 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(async_crypto), 0,
206 "Use asynchronous mode to parallelize crypto jobs.");
207 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, check_policy_history,
208 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(check_policy_history), 0,
209 "Use strict check of inbound packets to security policy compliance.");
210 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, natt_cksum_policy,
211 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(natt_cksum_policy), 0,
212 "Method to fix TCP/UDP checksum for transport mode IPsec after NAT.");
213 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, filtertunnel,
214 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_filtertunnel), 0,
215 "If set, filter packets from an IPsec tunnel.");
216 SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat,
217 ipsec4stat, "IPsec IPv4 statistics.");
218
219 struct timeval ipsec_warn_interval = { .tv_sec = 1, .tv_usec = 0 };
220 SYSCTL_TIMEVAL_SEC(_net_inet_ipsec, OID_AUTO, crypto_warn_interval, CTLFLAG_RW,
221 &ipsec_warn_interval,
222 "Delay in seconds between warnings of deprecated IPsec crypto algorithms.");
223
224 #ifdef REGRESSION
225 /*
226 * When set to 1, IPsec will send packets with the same sequence number.
227 * This allows to verify if the other side has proper replay attacks detection.
228 */
229 VNET_DEFINE(int, ipsec_replay) = 0;
230 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay,
231 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0,
232 "Emulate replay attack");
233 /*
234 * When set 1, IPsec will send packets with corrupted HMAC.
235 * This allows to verify if the other side properly detects modified packets.
236 */
237 VNET_DEFINE(int, ipsec_integrity) = 0;
238 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity,
239 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0,
240 "Emulate man-in-the-middle attack");
241 #endif
242
243 #ifdef INET6
244 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat);
245 VNET_PCPUSTAT_SYSINIT(ipsec6stat);
246
247 #ifdef VIMAGE
248 VNET_PCPUSTAT_SYSUNINIT(ipsec6stat);
249 #endif /* VIMAGE */
250
251 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE;
252 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE;
253 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE;
254 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE;
255 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */
256
257 VNET_DEFINE_STATIC(int, ip6_filtertunnel) = 0;
258 #define V_ip6_filtertunnel VNET(ip6_filtertunnel)
259
260 SYSCTL_DECL(_net_inet6_ipsec6);
261
262 /* net.inet6.ipsec6 */
263 SYSCTL_PROC(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy,
264 CTLTYPE_INT | CTLFLAG_VNET | CTLFLAG_RW, 0, 0, sysctl_def_policy, "I",
265 "IPsec default policy.");
266 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
267 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0,
268 "Default ESP transport mode level.");
269 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
270 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0,
271 "Default ESP tunnel mode level.");
272 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
273 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0,
274 "AH transfer mode default level.");
275 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
276 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0,
277 "AH tunnel mode default level.");
278 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ECN, ecn,
279 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0,
280 "Explicit Congestion Notification handling.");
281 SYSCTL_INT(_net_inet6_ipsec6, OID_AUTO, filtertunnel,
282 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_filtertunnel), 0,
283 "If set, filter packets from an IPsec tunnel.");
284 SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats,
285 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics.");
286 #endif /* INET6 */
287
288 static int ipsec_in_reject(struct secpolicy *, struct inpcb *,
289 const struct mbuf *);
290
291 #ifdef INET
292 static void ipsec4_get_ulp(const struct mbuf *, struct secpolicyindex *, int);
293 static void ipsec4_setspidx_ipaddr(const struct mbuf *,
294 struct secpolicyindex *);
295 #endif
296 #ifdef INET6
297 static void ipsec6_get_ulp(const struct mbuf *m, struct secpolicyindex *, int);
298 static void ipsec6_setspidx_ipaddr(const struct mbuf *,
299 struct secpolicyindex *);
300 #endif
301
302 /*
303 * Return a held reference to the default SP.
304 */
305 static struct secpolicy *
306 key_allocsp_default(void)
307 {
308
309 key_addref(V_def_policy);
310 return (V_def_policy);
311 }
312
313 static void
314 ipsec_invalidate_cache(struct inpcb *inp, u_int dir)
315 {
316 struct secpolicy *sp;
317
318 INP_WLOCK_ASSERT(inp);
319 if (dir == IPSEC_DIR_OUTBOUND) {
320 if (inp->inp_sp->flags & INP_INBOUND_POLICY)
321 return;
322 sp = inp->inp_sp->sp_in;
323 inp->inp_sp->sp_in = NULL;
324 } else {
325 if (inp->inp_sp->flags & INP_OUTBOUND_POLICY)
326 return;
327 sp = inp->inp_sp->sp_out;
328 inp->inp_sp->sp_out = NULL;
329 }
330 if (sp != NULL)
331 key_freesp(&sp); /* release extra reference */
332 }
333
334 static void
335 ipsec_cachepolicy(struct inpcb *inp, struct secpolicy *sp, u_int dir)
336 {
337 uint32_t genid;
338 int downgrade;
339
340 INP_LOCK_ASSERT(inp);
341
342 if (dir == IPSEC_DIR_OUTBOUND) {
343 /* Do we have configured PCB policy? */
344 if (inp->inp_sp->flags & INP_OUTBOUND_POLICY)
345 return;
346 /* Another thread has already set cached policy */
347 if (inp->inp_sp->sp_out != NULL)
348 return;
349 /*
350 * Do not cache OUTBOUND policy if PCB isn't connected,
351 * i.e. foreign address is INADDR_ANY/UNSPECIFIED.
352 */
353 #ifdef INET
354 if ((inp->inp_vflag & INP_IPV4) != 0 &&
355 inp->inp_faddr.s_addr == INADDR_ANY)
356 return;
357 #endif
358 #ifdef INET6
359 if ((inp->inp_vflag & INP_IPV6) != 0 &&
360 IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))
361 return;
362 #endif
363 } else {
364 /* Do we have configured PCB policy? */
365 if (inp->inp_sp->flags & INP_INBOUND_POLICY)
366 return;
367 /* Another thread has already set cached policy */
368 if (inp->inp_sp->sp_in != NULL)
369 return;
370 /*
371 * Do not cache INBOUND policy for listen socket,
372 * that is bound to INADDR_ANY/UNSPECIFIED address.
373 */
374 #ifdef INET
375 if ((inp->inp_vflag & INP_IPV4) != 0 &&
376 inp->inp_faddr.s_addr == INADDR_ANY)
377 return;
378 #endif
379 #ifdef INET6
380 if ((inp->inp_vflag & INP_IPV6) != 0 &&
381 IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))
382 return;
383 #endif
384 }
385 downgrade = 0;
386 if (!INP_WLOCKED(inp)) {
387 if ((downgrade = INP_TRY_UPGRADE(inp)) == 0)
388 return;
389 }
390 if (dir == IPSEC_DIR_OUTBOUND)
391 inp->inp_sp->sp_out = sp;
392 else
393 inp->inp_sp->sp_in = sp;
394 /*
395 * SP is already referenced by the lookup code.
396 * We take extra reference here to avoid race in the
397 * ipsec_getpcbpolicy() function - SP will not be freed in the
398 * time between we take SP pointer from the cache and key_addref()
399 * call.
400 */
401 key_addref(sp);
402 genid = key_getspgen();
403 if (genid != inp->inp_sp->genid) {
404 ipsec_invalidate_cache(inp, dir);
405 inp->inp_sp->genid = genid;
406 }
407 KEYDBG(IPSEC_STAMP,
408 printf("%s: PCB(%p): cached %s SP(%p)\n",
409 __func__, inp, dir == IPSEC_DIR_OUTBOUND ? "OUTBOUND":
410 "INBOUND", sp));
411 if (downgrade != 0)
412 INP_DOWNGRADE(inp);
413 }
414
415 static struct secpolicy *
416 ipsec_checkpolicy(struct secpolicy *sp, struct inpcb *inp, int *error)
417 {
418
419 /* Save found OUTBOUND policy into PCB SP cache. */
420 if (inp != NULL && inp->inp_sp != NULL && inp->inp_sp->sp_out == NULL)
421 ipsec_cachepolicy(inp, sp, IPSEC_DIR_OUTBOUND);
422
423 switch (sp->policy) {
424 default:
425 printf("%s: invalid policy %u\n", __func__, sp->policy);
426 /* FALLTHROUGH */
427 case IPSEC_POLICY_DISCARD:
428 *error = -EINVAL; /* Packet is discarded by caller. */
429 /* FALLTHROUGH */
430 case IPSEC_POLICY_BYPASS:
431 case IPSEC_POLICY_NONE:
432 key_freesp(&sp);
433 sp = NULL; /* NB: force NULL result. */
434 break;
435 case IPSEC_POLICY_IPSEC:
436 /* XXXAE: handle LARVAL SP */
437 break;
438 }
439 KEYDBG(IPSEC_DUMP,
440 printf("%s: get SP(%p), error %d\n", __func__, sp, *error));
441 return (sp);
442 }
443
444 static struct secpolicy *
445 ipsec_getpcbpolicy(struct inpcb *inp, u_int dir)
446 {
447 struct secpolicy *sp;
448 int flags, downgrade;
449
450 if (inp == NULL || inp->inp_sp == NULL)
451 return (NULL);
452
453 INP_LOCK_ASSERT(inp);
454
455 flags = inp->inp_sp->flags;
456 if (dir == IPSEC_DIR_OUTBOUND) {
457 sp = inp->inp_sp->sp_out;
458 flags &= INP_OUTBOUND_POLICY;
459 } else {
460 sp = inp->inp_sp->sp_in;
461 flags &= INP_INBOUND_POLICY;
462 }
463 /*
464 * Check flags. If we have PCB SP, just return it.
465 * Otherwise we need to check that cached SP entry isn't stale.
466 */
467 if (flags == 0) {
468 if (sp == NULL)
469 return (NULL);
470 if (inp->inp_sp->genid != key_getspgen()) {
471 /* Invalidate the cache. */
472 downgrade = 0;
473 if (!INP_WLOCKED(inp)) {
474 if ((downgrade = INP_TRY_UPGRADE(inp)) == 0)
475 return (NULL);
476 }
477 ipsec_invalidate_cache(inp, IPSEC_DIR_OUTBOUND);
478 ipsec_invalidate_cache(inp, IPSEC_DIR_INBOUND);
479 if (downgrade != 0)
480 INP_DOWNGRADE(inp);
481 return (NULL);
482 }
483 KEYDBG(IPSEC_STAMP,
484 printf("%s: PCB(%p): cache hit SP(%p)\n",
485 __func__, inp, sp));
486 /* Return referenced cached policy */
487 }
488 key_addref(sp);
489 return (sp);
490 }
491
492 #ifdef INET
493 static void
494 ipsec4_get_ulp(const struct mbuf *m, struct secpolicyindex *spidx,
495 int needport)
496 {
497 uint8_t nxt;
498 int off;
499
500 /* Sanity check. */
501 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),
502 ("packet too short"));
503
504 if (m->m_len >= sizeof (struct ip)) {
505 const struct ip *ip = mtod(m, const struct ip *);
506 if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
507 goto done;
508 off = ip->ip_hl << 2;
509 nxt = ip->ip_p;
510 } else {
511 struct ip ih;
512
513 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih);
514 if (ih.ip_off & htons(IP_MF | IP_OFFMASK))
515 goto done;
516 off = ih.ip_hl << 2;
517 nxt = ih.ip_p;
518 }
519
520 while (off < m->m_pkthdr.len) {
521 struct ip6_ext ip6e;
522 struct tcphdr th;
523 struct udphdr uh;
524
525 switch (nxt) {
526 case IPPROTO_TCP:
527 spidx->ul_proto = nxt;
528 if (!needport)
529 goto done_proto;
530 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
531 goto done;
532 m_copydata(m, off, sizeof (th), (caddr_t) &th);
533 spidx->src.sin.sin_port = th.th_sport;
534 spidx->dst.sin.sin_port = th.th_dport;
535 return;
536 case IPPROTO_UDP:
537 spidx->ul_proto = nxt;
538 if (!needport)
539 goto done_proto;
540 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
541 goto done;
542 m_copydata(m, off, sizeof (uh), (caddr_t) &uh);
543 spidx->src.sin.sin_port = uh.uh_sport;
544 spidx->dst.sin.sin_port = uh.uh_dport;
545 return;
546 case IPPROTO_AH:
547 if (off + sizeof(ip6e) > m->m_pkthdr.len)
548 goto done;
549 /* XXX Sigh, this works but is totally bogus. */
550 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e);
551 off += (ip6e.ip6e_len + 2) << 2;
552 nxt = ip6e.ip6e_nxt;
553 break;
554 case IPPROTO_ICMP:
555 default:
556 /* XXX Intermediate headers??? */
557 spidx->ul_proto = nxt;
558 goto done_proto;
559 }
560 }
561 done:
562 spidx->ul_proto = IPSEC_ULPROTO_ANY;
563 done_proto:
564 spidx->src.sin.sin_port = IPSEC_PORT_ANY;
565 spidx->dst.sin.sin_port = IPSEC_PORT_ANY;
566 KEYDBG(IPSEC_DUMP,
567 printf("%s: ", __func__); kdebug_secpolicyindex(spidx, NULL));
568 }
569
570 static void
571 ipsec4_setspidx_ipaddr(const struct mbuf *m, struct secpolicyindex *spidx)
572 {
573
574 ipsec4_setsockaddrs(m, &spidx->src, &spidx->dst);
575 spidx->prefs = sizeof(struct in_addr) << 3;
576 spidx->prefd = sizeof(struct in_addr) << 3;
577 }
578
579 static struct secpolicy *
580 ipsec4_getpolicy(const struct mbuf *m, struct inpcb *inp, u_int dir,
581 int needport)
582 {
583 struct secpolicyindex spidx;
584 struct secpolicy *sp;
585
586 sp = ipsec_getpcbpolicy(inp, dir);
587 if (sp == NULL && key_havesp(dir)) {
588 /* Make an index to look for a policy. */
589 ipsec4_setspidx_ipaddr(m, &spidx);
590 ipsec4_get_ulp(m, &spidx, needport);
591 spidx.dir = dir;
592 sp = key_allocsp(&spidx, dir);
593 }
594 if (sp == NULL) /* No SP found, use system default. */
595 sp = key_allocsp_default();
596 return (sp);
597 }
598
599 /*
600 * Check security policy for *OUTBOUND* IPv4 packet.
601 */
602 struct secpolicy *
603 ipsec4_checkpolicy(const struct mbuf *m, struct inpcb *inp, int *error,
604 int needport)
605 {
606 struct secpolicy *sp;
607
608 *error = 0;
609 sp = ipsec4_getpolicy(m, inp, IPSEC_DIR_OUTBOUND, needport);
610 if (sp != NULL)
611 sp = ipsec_checkpolicy(sp, inp, error);
612 if (sp == NULL) {
613 switch (*error) {
614 case 0: /* No IPsec required: BYPASS or NONE */
615 break;
616 case -EINVAL:
617 IPSECSTAT_INC(ips_out_polvio);
618 break;
619 default:
620 IPSECSTAT_INC(ips_out_inval);
621 }
622 }
623 KEYDBG(IPSEC_STAMP,
624 printf("%s: using SP(%p), error %d\n", __func__, sp, *error));
625 if (sp != NULL)
626 KEYDBG(IPSEC_DATA, kdebug_secpolicy(sp));
627 return (sp);
628 }
629
630 /*
631 * Check IPv4 packet against *INBOUND* security policy.
632 * This function is called from tcp_input(), udp_input(),
633 * rip_input() and sctp_input().
634 */
635 int
636 ipsec4_in_reject(const struct mbuf *m, struct inpcb *inp)
637 {
638 struct secpolicy *sp;
639 int result;
640
641 sp = ipsec4_getpolicy(m, inp, IPSEC_DIR_INBOUND, 0);
642 result = ipsec_in_reject(sp, inp, m);
643 key_freesp(&sp);
644 if (result != 0)
645 IPSECSTAT_INC(ips_in_polvio);
646 return (result);
647 }
648
649 /*
650 * IPSEC_CAP() method implementation for IPv4.
651 */
652 int
653 ipsec4_capability(struct mbuf *m, u_int cap)
654 {
655
656 switch (cap) {
657 case IPSEC_CAP_BYPASS_FILTER:
658 /*
659 * Bypass packet filtering for packets previously handled
660 * by IPsec.
661 */
662 if (!V_ip4_filtertunnel &&
663 m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL)
664 return (1);
665 return (0);
666 case IPSEC_CAP_OPERABLE:
667 /* Do we have active security policies? */
668 if (key_havesp(IPSEC_DIR_INBOUND) != 0 ||
669 key_havesp(IPSEC_DIR_OUTBOUND) != 0)
670 return (1);
671 return (0);
672 };
673 return (EOPNOTSUPP);
674 }
675
676 #endif /* INET */
677
678 #ifdef INET6
679 static void
680 ipsec6_get_ulp(const struct mbuf *m, struct secpolicyindex *spidx,
681 int needport)
682 {
683 struct tcphdr th;
684 struct udphdr uh;
685 struct icmp6_hdr ih;
686 int off, nxt;
687
688 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip6_hdr),
689 ("packet too short"));
690
691 /* Set default. */
692 spidx->ul_proto = IPSEC_ULPROTO_ANY;
693 spidx->src.sin6.sin6_port = IPSEC_PORT_ANY;
694 spidx->dst.sin6.sin6_port = IPSEC_PORT_ANY;
695
696 nxt = -1;
697 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
698 if (off < 0 || m->m_pkthdr.len < off)
699 return;
700
701 switch (nxt) {
702 case IPPROTO_TCP:
703 spidx->ul_proto = nxt;
704 if (!needport)
705 break;
706 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
707 break;
708 m_copydata(m, off, sizeof(th), (caddr_t)&th);
709 spidx->src.sin6.sin6_port = th.th_sport;
710 spidx->dst.sin6.sin6_port = th.th_dport;
711 break;
712 case IPPROTO_UDP:
713 spidx->ul_proto = nxt;
714 if (!needport)
715 break;
716 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
717 break;
718 m_copydata(m, off, sizeof(uh), (caddr_t)&uh);
719 spidx->src.sin6.sin6_port = uh.uh_sport;
720 spidx->dst.sin6.sin6_port = uh.uh_dport;
721 break;
722 case IPPROTO_ICMPV6:
723 spidx->ul_proto = nxt;
724 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len)
725 break;
726 m_copydata(m, off, sizeof(ih), (caddr_t)&ih);
727 spidx->src.sin6.sin6_port = htons((uint16_t)ih.icmp6_type);
728 spidx->dst.sin6.sin6_port = htons((uint16_t)ih.icmp6_code);
729 break;
730 default:
731 /* XXX Intermediate headers??? */
732 spidx->ul_proto = nxt;
733 break;
734 }
735 KEYDBG(IPSEC_DUMP,
736 printf("%s: ", __func__); kdebug_secpolicyindex(spidx, NULL));
737 }
738
739 static void
740 ipsec6_setspidx_ipaddr(const struct mbuf *m, struct secpolicyindex *spidx)
741 {
742
743 ipsec6_setsockaddrs(m, &spidx->src, &spidx->dst);
744 spidx->prefs = sizeof(struct in6_addr) << 3;
745 spidx->prefd = sizeof(struct in6_addr) << 3;
746 }
747
748 static struct secpolicy *
749 ipsec6_getpolicy(const struct mbuf *m, struct inpcb *inp, u_int dir,
750 int needport)
751 {
752 struct secpolicyindex spidx;
753 struct secpolicy *sp;
754
755 sp = ipsec_getpcbpolicy(inp, dir);
756 if (sp == NULL && key_havesp(dir)) {
757 /* Make an index to look for a policy. */
758 ipsec6_setspidx_ipaddr(m, &spidx);
759 ipsec6_get_ulp(m, &spidx, needport);
760 spidx.dir = dir;
761 sp = key_allocsp(&spidx, dir);
762 }
763 if (sp == NULL) /* No SP found, use system default. */
764 sp = key_allocsp_default();
765 return (sp);
766 }
767
768 /*
769 * Check security policy for *OUTBOUND* IPv6 packet.
770 */
771 struct secpolicy *
772 ipsec6_checkpolicy(const struct mbuf *m, struct inpcb *inp, int *error,
773 int needport)
774 {
775 struct secpolicy *sp;
776
777 *error = 0;
778 sp = ipsec6_getpolicy(m, inp, IPSEC_DIR_OUTBOUND, needport);
779 if (sp != NULL)
780 sp = ipsec_checkpolicy(sp, inp, error);
781 if (sp == NULL) {
782 switch (*error) {
783 case 0: /* No IPsec required: BYPASS or NONE */
784 break;
785 case -EINVAL:
786 IPSEC6STAT_INC(ips_out_polvio);
787 break;
788 default:
789 IPSEC6STAT_INC(ips_out_inval);
790 }
791 }
792 KEYDBG(IPSEC_STAMP,
793 printf("%s: using SP(%p), error %d\n", __func__, sp, *error));
794 if (sp != NULL)
795 KEYDBG(IPSEC_DATA, kdebug_secpolicy(sp));
796 return (sp);
797 }
798
799 /*
800 * Check IPv6 packet against inbound security policy.
801 * This function is called from tcp6_input(), udp6_input(),
802 * rip6_input() and sctp_input().
803 */
804 int
805 ipsec6_in_reject(const struct mbuf *m, struct inpcb *inp)
806 {
807 struct secpolicy *sp;
808 int result;
809
810 sp = ipsec6_getpolicy(m, inp, IPSEC_DIR_INBOUND, 0);
811 result = ipsec_in_reject(sp, inp, m);
812 key_freesp(&sp);
813 if (result)
814 IPSEC6STAT_INC(ips_in_polvio);
815 return (result);
816 }
817
818 /*
819 * IPSEC_CAP() method implementation for IPv6.
820 */
821 int
822 ipsec6_capability(struct mbuf *m, u_int cap)
823 {
824
825 switch (cap) {
826 case IPSEC_CAP_BYPASS_FILTER:
827 /*
828 * Bypass packet filtering for packets previously handled
829 * by IPsec.
830 */
831 if (!V_ip6_filtertunnel &&
832 m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL)
833 return (1);
834 return (0);
835 case IPSEC_CAP_OPERABLE:
836 /* Do we have active security policies? */
837 if (key_havesp(IPSEC_DIR_INBOUND) != 0 ||
838 key_havesp(IPSEC_DIR_OUTBOUND) != 0)
839 return (1);
840 return (0);
841 };
842 return (EOPNOTSUPP);
843 }
844 #endif /* INET6 */
845
846 int
847 ipsec_run_hhooks(struct ipsec_ctx_data *ctx, int type)
848 {
849 int idx;
850
851 switch (ctx->af) {
852 #ifdef INET
853 case AF_INET:
854 idx = HHOOK_IPSEC_INET;
855 break;
856 #endif
857 #ifdef INET6
858 case AF_INET6:
859 idx = HHOOK_IPSEC_INET6;
860 break;
861 #endif
862 default:
863 return (EPFNOSUPPORT);
864 }
865 if (type == HHOOK_TYPE_IPSEC_IN)
866 HHOOKS_RUN_IF(V_ipsec_hhh_in[idx], ctx, NULL);
867 else
868 HHOOKS_RUN_IF(V_ipsec_hhh_out[idx], ctx, NULL);
869 if (*ctx->mp == NULL)
870 return (EACCES);
871 return (0);
872 }
873
874 /*
875 * Return current level.
876 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned.
877 */
878 u_int
879 ipsec_get_reqlevel(struct secpolicy *sp, u_int idx)
880 {
881 struct ipsecrequest *isr;
882 u_int esp_trans_deflev, esp_net_deflev;
883 u_int ah_trans_deflev, ah_net_deflev;
884 u_int level = 0;
885
886 IPSEC_ASSERT(idx < sp->tcount, ("Wrong IPsec request index %d", idx));
887 /* XXX Note that we have ipseclog() expanded here - code sync issue. */
888 #define IPSEC_CHECK_DEFAULT(lev) \
889 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE && \
890 (lev) != IPSEC_LEVEL_UNIQUE) \
891 ? (V_ipsec_debug ? \
892 log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\
893 (lev), IPSEC_LEVEL_REQUIRE) : 0), \
894 (lev) = IPSEC_LEVEL_REQUIRE, (lev) : (lev))
895
896 /*
897 * IPsec VTI uses unique security policy with fake spidx filled
898 * with zeroes. Just return IPSEC_LEVEL_REQUIRE instead of doing
899 * full level lookup for such policies.
900 */
901 if (sp->state == IPSEC_SPSTATE_IFNET) {
902 IPSEC_ASSERT(sp->req[idx]->level == IPSEC_LEVEL_UNIQUE,
903 ("Wrong IPsec request level %d", sp->req[idx]->level));
904 return (IPSEC_LEVEL_REQUIRE);
905 }
906
907 /* Set default level. */
908 switch (sp->spidx.src.sa.sa_family) {
909 #ifdef INET
910 case AF_INET:
911 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev);
912 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev);
913 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev);
914 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev);
915 break;
916 #endif
917 #ifdef INET6
918 case AF_INET6:
919 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev);
920 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev);
921 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev);
922 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev);
923 break;
924 #endif /* INET6 */
925 default:
926 panic("%s: unknown af %u",
927 __func__, sp->spidx.src.sa.sa_family);
928 }
929
930 #undef IPSEC_CHECK_DEFAULT
931
932 isr = sp->req[idx];
933 /* Set level. */
934 switch (isr->level) {
935 case IPSEC_LEVEL_DEFAULT:
936 switch (isr->saidx.proto) {
937 case IPPROTO_ESP:
938 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
939 level = esp_net_deflev;
940 else
941 level = esp_trans_deflev;
942 break;
943 case IPPROTO_AH:
944 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
945 level = ah_net_deflev;
946 else
947 level = ah_trans_deflev;
948 break;
949 case IPPROTO_IPCOMP:
950 /*
951 * We don't really care, as IPcomp document says that
952 * we shouldn't compress small packets.
953 */
954 level = IPSEC_LEVEL_USE;
955 break;
956 default:
957 panic("%s: Illegal protocol defined %u\n", __func__,
958 isr->saidx.proto);
959 }
960 break;
961
962 case IPSEC_LEVEL_USE:
963 case IPSEC_LEVEL_REQUIRE:
964 level = isr->level;
965 break;
966 case IPSEC_LEVEL_UNIQUE:
967 level = IPSEC_LEVEL_REQUIRE;
968 break;
969
970 default:
971 panic("%s: Illegal IPsec level %u\n", __func__, isr->level);
972 }
973
974 return (level);
975 }
976
977 static int
978 ipsec_check_history(const struct mbuf *m, struct secpolicy *sp, u_int idx)
979 {
980 struct xform_history *xh;
981 struct m_tag *mtag;
982
983 mtag = NULL;
984 while ((mtag = m_tag_find(__DECONST(struct mbuf *, m),
985 PACKET_TAG_IPSEC_IN_DONE, mtag)) != NULL) {
986 xh = (struct xform_history *)(mtag + 1);
987 KEYDBG(IPSEC_DATA,
988 char buf[IPSEC_ADDRSTRLEN];
989 printf("%s: mode %s proto %u dst %s\n", __func__,
990 kdebug_secasindex_mode(xh->mode), xh->proto,
991 ipsec_address(&xh->dst, buf, sizeof(buf))));
992 if (xh->proto != sp->req[idx]->saidx.proto)
993 continue;
994 /* If SA had IPSEC_MODE_ANY, consider this as match. */
995 if (xh->mode != sp->req[idx]->saidx.mode &&
996 xh->mode != IPSEC_MODE_ANY)
997 continue;
998 /*
999 * For transport mode IPsec request doesn't contain
1000 * addresses. We need to use address from spidx.
1001 */
1002 if (sp->req[idx]->saidx.mode == IPSEC_MODE_TRANSPORT) {
1003 if (key_sockaddrcmp_withmask(&xh->dst.sa,
1004 &sp->spidx.dst.sa, sp->spidx.prefd) != 0)
1005 continue;
1006 } else {
1007 if (key_sockaddrcmp(&xh->dst.sa,
1008 &sp->req[idx]->saidx.dst.sa, 0) != 0)
1009 continue;
1010 }
1011 return (0); /* matched */
1012 }
1013 return (1);
1014 }
1015
1016 /*
1017 * Check security policy requirements against the actual
1018 * packet contents. Return one if the packet should be
1019 * reject as "invalid"; otherwiser return zero to have the
1020 * packet treated as "valid".
1021 *
1022 * OUT:
1023 * 0: valid
1024 * 1: invalid
1025 */
1026 static int
1027 ipsec_in_reject(struct secpolicy *sp, struct inpcb *inp, const struct mbuf *m)
1028 {
1029 int i;
1030
1031 KEYDBG(IPSEC_STAMP,
1032 printf("%s: PCB(%p): using SP(%p)\n", __func__, inp, sp));
1033 KEYDBG(IPSEC_DATA, kdebug_secpolicy(sp));
1034
1035 if (inp != NULL && inp->inp_sp != NULL && inp->inp_sp->sp_in == NULL)
1036 ipsec_cachepolicy(inp, sp, IPSEC_DIR_INBOUND);
1037
1038 /* Check policy. */
1039 switch (sp->policy) {
1040 case IPSEC_POLICY_DISCARD:
1041 return (1);
1042 case IPSEC_POLICY_BYPASS:
1043 case IPSEC_POLICY_NONE:
1044 return (0);
1045 }
1046
1047 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1048 ("invalid policy %u", sp->policy));
1049
1050 /*
1051 * ipsec[46]_common_input_cb after each transform adds
1052 * PACKET_TAG_IPSEC_IN_DONE mbuf tag. It contains SPI, proto, mode
1053 * and destination address from saidx. We can compare info from
1054 * these tags with requirements in SP.
1055 */
1056 for (i = 0; i < sp->tcount; i++) {
1057 /*
1058 * Do not check IPcomp, since IPcomp document
1059 * says that we shouldn't compress small packets.
1060 * IPComp policy should always be treated as being
1061 * in "use" level.
1062 */
1063 if (sp->req[i]->saidx.proto == IPPROTO_IPCOMP ||
1064 ipsec_get_reqlevel(sp, i) != IPSEC_LEVEL_REQUIRE)
1065 continue;
1066 if (V_check_policy_history != 0 &&
1067 ipsec_check_history(m, sp, i) != 0)
1068 return (1);
1069 else switch (sp->req[i]->saidx.proto) {
1070 case IPPROTO_ESP:
1071 if ((m->m_flags & M_DECRYPTED) == 0) {
1072 KEYDBG(IPSEC_DUMP,
1073 printf("%s: ESP m_flags:%x\n", __func__,
1074 m->m_flags));
1075 return (1);
1076 }
1077 break;
1078 case IPPROTO_AH:
1079 if ((m->m_flags & M_AUTHIPHDR) == 0) {
1080 KEYDBG(IPSEC_DUMP,
1081 printf("%s: AH m_flags:%x\n", __func__,
1082 m->m_flags));
1083 return (1);
1084 }
1085 break;
1086 }
1087 }
1088 return (0); /* Valid. */
1089 }
1090
1091 /*
1092 * Compute the byte size to be occupied by IPsec header.
1093 * In case it is tunnelled, it includes the size of outer IP header.
1094 */
1095 static size_t
1096 ipsec_hdrsiz_internal(struct secpolicy *sp)
1097 {
1098 size_t size;
1099 int i;
1100
1101 KEYDBG(IPSEC_STAMP, printf("%s: using SP(%p)\n", __func__, sp));
1102 KEYDBG(IPSEC_DATA, kdebug_secpolicy(sp));
1103
1104 switch (sp->policy) {
1105 case IPSEC_POLICY_DISCARD:
1106 case IPSEC_POLICY_BYPASS:
1107 case IPSEC_POLICY_NONE:
1108 return (0);
1109 }
1110
1111 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1112 ("invalid policy %u", sp->policy));
1113
1114 /*
1115 * XXX: for each transform we need to lookup suitable SA
1116 * and use info from SA to calculate headers size.
1117 * XXX: for NAT-T we need to cosider UDP header size.
1118 */
1119 size = 0;
1120 for (i = 0; i < sp->tcount; i++) {
1121 switch (sp->req[i]->saidx.proto) {
1122 case IPPROTO_ESP:
1123 size += esp_hdrsiz(NULL);
1124 break;
1125 case IPPROTO_AH:
1126 size += ah_hdrsiz(NULL);
1127 break;
1128 case IPPROTO_IPCOMP:
1129 size += sizeof(struct ipcomp);
1130 break;
1131 }
1132
1133 if (sp->req[i]->saidx.mode == IPSEC_MODE_TUNNEL) {
1134 switch (sp->req[i]->saidx.dst.sa.sa_family) {
1135 #ifdef INET
1136 case AF_INET:
1137 size += sizeof(struct ip);
1138 break;
1139 #endif
1140 #ifdef INET6
1141 case AF_INET6:
1142 size += sizeof(struct ip6_hdr);
1143 break;
1144 #endif
1145 default:
1146 ipseclog((LOG_ERR, "%s: unknown AF %d in "
1147 "IPsec tunnel SA\n", __func__,
1148 sp->req[i]->saidx.dst.sa.sa_family));
1149 break;
1150 }
1151 }
1152 }
1153 return (size);
1154 }
1155
1156 /*
1157 * Compute ESP/AH header size for protocols with PCB, including
1158 * outer IP header. Currently only tcp_output() uses it.
1159 */
1160 size_t
1161 ipsec_hdrsiz_inpcb(struct inpcb *inp)
1162 {
1163 struct secpolicyindex spidx;
1164 struct secpolicy *sp;
1165 size_t sz;
1166
1167 sp = ipsec_getpcbpolicy(inp, IPSEC_DIR_OUTBOUND);
1168 if (sp == NULL && key_havesp(IPSEC_DIR_OUTBOUND)) {
1169 ipsec_setspidx_inpcb(inp, &spidx, IPSEC_DIR_OUTBOUND);
1170 sp = key_allocsp(&spidx, IPSEC_DIR_OUTBOUND);
1171 }
1172 if (sp == NULL)
1173 sp = key_allocsp_default();
1174 sz = ipsec_hdrsiz_internal(sp);
1175 key_freesp(&sp);
1176 return (sz);
1177 }
1178
1179 /*
1180 * Check the variable replay window.
1181 * ipsec_chkreplay() performs replay check before ICV verification.
1182 * ipsec_updatereplay() updates replay bitmap. This must be called after
1183 * ICV verification (it also performs replay check, which is usually done
1184 * beforehand).
1185 * 0 (zero) is returned if packet disallowed, 1 if packet permitted.
1186 *
1187 * Based on RFC 6479. Blocks are 32 bits unsigned integers
1188 */
1189
1190 #define IPSEC_BITMAP_INDEX_MASK(w) (w - 1)
1191 #define IPSEC_REDUNDANT_BIT_SHIFTS 5
1192 #define IPSEC_REDUNDANT_BITS (1 << IPSEC_REDUNDANT_BIT_SHIFTS)
1193 #define IPSEC_BITMAP_LOC_MASK (IPSEC_REDUNDANT_BITS - 1)
1194
1195 int
1196 ipsec_chkreplay(uint32_t seq, struct secasvar *sav)
1197 {
1198 const struct secreplay *replay;
1199 uint32_t wsizeb; /* Constant: window size. */
1200 int index, bit_location;
1201
1202 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1203 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1204
1205 replay = sav->replay;
1206
1207 /* No need to check replay if disabled. */
1208 if (replay->wsize == 0)
1209 return (1);
1210
1211 /* Constant. */
1212 wsizeb = replay->wsize << 3;
1213
1214 /* Sequence number of 0 is invalid. */
1215 if (seq == 0)
1216 return (0);
1217
1218 /* First time is always okay. */
1219 if (replay->count == 0)
1220 return (1);
1221
1222 /* Larger sequences are okay. */
1223 if (seq > replay->lastseq)
1224 return (1);
1225
1226 /* Over range to check, i.e. too old or wrapped. */
1227 if (replay->lastseq - seq >= wsizeb)
1228 return (0);
1229
1230 /* The sequence is inside the sliding window
1231 * now check the bit in the bitmap
1232 * bit location only depends on the sequence number
1233 */
1234 bit_location = seq & IPSEC_BITMAP_LOC_MASK;
1235 index = (seq >> IPSEC_REDUNDANT_BIT_SHIFTS)
1236 & IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size);
1237
1238 /* This packet already seen? */
1239 if ((replay->bitmap)[index] & (1 << bit_location))
1240 return (0);
1241 return (1);
1242 }
1243
1244 /*
1245 * Check replay counter whether to update or not.
1246 * OUT: 0: OK
1247 * 1: NG
1248 */
1249 int
1250 ipsec_updatereplay(uint32_t seq, struct secasvar *sav)
1251 {
1252 char buf[128];
1253 struct secreplay *replay;
1254 uint32_t wsizeb; /* Constant: window size. */
1255 int diff, index, bit_location;
1256
1257 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1258 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1259
1260 replay = sav->replay;
1261
1262 if (replay->wsize == 0)
1263 goto ok; /* No need to check replay. */
1264
1265 /* Constant. */
1266 wsizeb = replay->wsize << 3;
1267
1268 /* Sequence number of 0 is invalid. */
1269 if (seq == 0)
1270 return (1);
1271
1272 /* The packet is too old, no need to update */
1273 if (wsizeb + seq < replay->lastseq)
1274 goto ok;
1275
1276 /* Now update the bit */
1277 index = (seq >> IPSEC_REDUNDANT_BIT_SHIFTS);
1278
1279 /* First check if the sequence number is in the range */
1280 if (seq > replay->lastseq) {
1281 int id;
1282 int index_cur = replay->lastseq >> IPSEC_REDUNDANT_BIT_SHIFTS;
1283
1284 diff = index - index_cur;
1285 if (diff > replay->bitmap_size) {
1286 /* something unusual in this case */
1287 diff = replay->bitmap_size;
1288 }
1289
1290 for (id = 0; id < diff; ++id) {
1291 replay->bitmap[(id + index_cur + 1)
1292 & IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size)] = 0;
1293 }
1294
1295 replay->lastseq = seq;
1296 }
1297
1298 index &= IPSEC_BITMAP_INDEX_MASK(replay->bitmap_size);
1299 bit_location = seq & IPSEC_BITMAP_LOC_MASK;
1300
1301 /* this packet has already been received */
1302 if (replay->bitmap[index] & (1 << bit_location))
1303 return (1);
1304
1305 replay->bitmap[index] |= (1 << bit_location);
1306
1307 ok:
1308 if (replay->count == ~0) {
1309
1310 /* Set overflow flag. */
1311 replay->overflow++;
1312
1313 /* Don't increment, no more packets accepted. */
1314 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) {
1315 if (sav->sah->saidx.proto == IPPROTO_AH)
1316 AHSTAT_INC(ahs_wrap);
1317 else if (sav->sah->saidx.proto == IPPROTO_ESP)
1318 ESPSTAT_INC(esps_wrap);
1319 return (1);
1320 }
1321
1322 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n",
1323 __func__, replay->overflow,
1324 ipsec_sa2str(sav, buf, sizeof(buf))));
1325 }
1326
1327 replay->count++;
1328 return (0);
1329 }
1330
1331 int
1332 ipsec_updateid(struct secasvar *sav, crypto_session_t *new,
1333 crypto_session_t *old)
1334 {
1335 crypto_session_t tmp;
1336
1337 /*
1338 * tdb_cryptoid is initialized by xform_init().
1339 * Then it can be changed only when some crypto error occurred or
1340 * when SA is deleted. We stored used cryptoid in the xform_data
1341 * structure. In case when crypto error occurred and crypto
1342 * subsystem has reinited the session, it returns new cryptoid
1343 * and EAGAIN error code.
1344 *
1345 * This function will be called when we got EAGAIN from crypto
1346 * subsystem.
1347 * *new is cryptoid that was returned by crypto subsystem in
1348 * the crp_sid.
1349 * *old is the original cryptoid that we stored in xform_data.
1350 *
1351 * For first failed request *old == sav->tdb_cryptoid, then
1352 * we update sav->tdb_cryptoid and redo crypto_dispatch().
1353 * For next failed request *old != sav->tdb_cryptoid, then
1354 * we store cryptoid from first request into the *new variable
1355 * and crp_sid from this second session will be returned via
1356 * *old pointer, so caller can release second session.
1357 *
1358 * XXXAE: check this more carefully.
1359 */
1360 KEYDBG(IPSEC_STAMP,
1361 printf("%s: SA(%p) moves cryptoid %p -> %p\n",
1362 __func__, sav, *old, *new));
1363 KEYDBG(IPSEC_DATA, kdebug_secasv(sav));
1364 SECASVAR_LOCK(sav);
1365 if (sav->tdb_cryptoid != *old) {
1366 /* cryptoid was already updated */
1367 tmp = *new;
1368 *new = sav->tdb_cryptoid;
1369 *old = tmp;
1370 SECASVAR_UNLOCK(sav);
1371 return (1);
1372 }
1373 sav->tdb_cryptoid = *new;
1374 SECASVAR_UNLOCK(sav);
1375 return (0);
1376 }
1377
1378 int
1379 ipsec_initialized(void)
1380 {
1381
1382 return (V_def_policy != NULL);
1383 }
1384
1385 static void
1386 def_policy_init(const void *unused __unused)
1387 {
1388
1389 V_def_policy = key_newsp();
1390 if (V_def_policy != NULL) {
1391 V_def_policy->policy = IPSEC_POLICY_NONE;
1392 /* Force INPCB SP cache invalidation */
1393 key_bumpspgen();
1394 } else
1395 printf("%s: failed to initialize default policy\n", __func__);
1396 }
1397
1398
1399 static void
1400 def_policy_uninit(const void *unused __unused)
1401 {
1402
1403 if (V_def_policy != NULL) {
1404 key_freesp(&V_def_policy);
1405 key_bumpspgen();
1406 }
1407 }
1408
1409 VNET_SYSINIT(def_policy_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST,
1410 def_policy_init, NULL);
1411 VNET_SYSUNINIT(def_policy_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST,
1412 def_policy_uninit, NULL);
Cache object: 730c0e6977a6aafd5d2f41db0b544ded
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