FreeBSD/Linux Kernel Cross Reference
sys/netipsec/ipsec.c
1 /* $FreeBSD: releng/9.2/sys/netipsec/ipsec.c 252692 2013-07-04 08:57:13Z ae $ */
2 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */
3
4 /*-
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 /*
34 * IPsec controller part.
35 */
36
37 #include "opt_inet.h"
38 #include "opt_inet6.h"
39 #include "opt_ipsec.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/malloc.h>
44 #include <sys/mbuf.h>
45 #include <sys/domain.h>
46 #include <sys/priv.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/errno.h>
51 #include <sys/time.h>
52 #include <sys/kernel.h>
53 #include <sys/syslog.h>
54 #include <sys/sysctl.h>
55 #include <sys/proc.h>
56
57 #include <net/if.h>
58 #include <net/route.h>
59 #include <net/vnet.h>
60
61 #include <netinet/in.h>
62 #include <netinet/in_systm.h>
63 #include <netinet/ip.h>
64 #include <netinet/ip_var.h>
65 #include <netinet/in_var.h>
66 #include <netinet/udp.h>
67 #include <netinet/udp_var.h>
68 #include <netinet/tcp.h>
69 #include <netinet/udp.h>
70
71 #include <netinet/ip6.h>
72 #ifdef INET6
73 #include <netinet6/ip6_var.h>
74 #endif
75 #include <netinet/in_pcb.h>
76 #ifdef INET6
77 #include <netinet/icmp6.h>
78 #endif
79
80 #include <sys/types.h>
81 #include <netipsec/ipsec.h>
82 #ifdef INET6
83 #include <netipsec/ipsec6.h>
84 #endif
85 #include <netipsec/ah_var.h>
86 #include <netipsec/esp_var.h>
87 #include <netipsec/ipcomp.h> /*XXX*/
88 #include <netipsec/ipcomp_var.h>
89
90 #include <netipsec/key.h>
91 #include <netipsec/keydb.h>
92 #include <netipsec/key_debug.h>
93
94 #include <netipsec/xform.h>
95
96 #include <machine/in_cksum.h>
97
98 #include <opencrypto/cryptodev.h>
99
100 #ifdef IPSEC_DEBUG
101 VNET_DEFINE(int, ipsec_debug) = 1;
102 #else
103 VNET_DEFINE(int, ipsec_debug) = 0;
104 #endif
105
106 /* NB: name changed so netstat doesn't use it. */
107 VNET_DEFINE(struct ipsecstat, ipsec4stat);
108 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */
109 /* DF bit on encap. 0: clear 1: set 2: copy */
110 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0;
111 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE;
112 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE;
113 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE;
114 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE;
115 VNET_DEFINE(struct secpolicy, ip4_def_policy);
116 /* ECN ignore(-1)/forbidden(0)/allowed(1) */
117 VNET_DEFINE(int, ip4_ipsec_ecn) = 0;
118 VNET_DEFINE(int, ip4_esp_randpad) = -1;
119
120 /*
121 * Crypto support requirements:
122 *
123 * 1 require hardware support
124 * -1 require software support
125 * 0 take anything
126 */
127 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE;
128
129 FEATURE(ipsec, "Internet Protocol Security (IPsec)");
130 #ifdef IPSEC_NAT_T
131 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')");
132 #endif
133
134 SYSCTL_DECL(_net_inet_ipsec);
135
136 /* net.inet.ipsec */
137 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy,
138 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0,
139 "IPsec default policy.");
140 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
141 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0,
142 "Default ESP transport mode level");
143 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
144 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0,
145 "Default ESP tunnel mode level.");
146 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
147 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0,
148 "AH transfer mode default level.");
149 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
150 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0,
151 "AH tunnel mode default level.");
152 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos,
153 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0,
154 "If set clear type-of-service field when doing AH computation.");
155 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask,
156 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0,
157 "If not set clear offset field mask when doing AH computation.");
158 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit,
159 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0,
160 "Do not fragment bit on encap.");
161 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn,
162 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0,
163 "Explicit Congestion Notification handling.");
164 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug,
165 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0,
166 "Enable IPsec debugging output when set.");
167 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support,
168 CTLFLAG_RW, &VNET_NAME(crypto_support), 0,
169 "Crypto driver selection.");
170 SYSCTL_VNET_STRUCT(_net_inet_ipsec, OID_AUTO, ipsecstats,
171 CTLFLAG_RD, &VNET_NAME(ipsec4stat), ipsecstat,
172 "IPsec IPv4 statistics.");
173
174 #ifdef REGRESSION
175 /*
176 * When set to 1, IPsec will send packets with the same sequence number.
177 * This allows to verify if the other side has proper replay attacks detection.
178 */
179 VNET_DEFINE(int, ipsec_replay) = 0;
180 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay,
181 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0,
182 "Emulate replay attack");
183 /*
184 * When set 1, IPsec will send packets with corrupted HMAC.
185 * This allows to verify if the other side properly detects modified packets.
186 */
187 VNET_DEFINE(int, ipsec_integrity) = 0;
188 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity,
189 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0,
190 "Emulate man-in-the-middle attack");
191 #endif
192
193 #ifdef INET6
194 VNET_DEFINE(struct ipsecstat, ipsec6stat);
195 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE;
196 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE;
197 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE;
198 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE;
199 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */
200
201 SYSCTL_DECL(_net_inet6_ipsec6);
202
203 /* net.inet6.ipsec6 */
204 #ifdef COMPAT_KAME
205 SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD,
206 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics.");
207 #endif /* COMPAT_KAME */
208 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW,
209 &VNET_NAME(ip4_def_policy).policy, 0,
210 "IPsec default policy.");
211 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV,
212 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0,
213 "Default ESP transport mode level.");
214 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV,
215 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0,
216 "Default ESP tunnel mode level.");
217 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV,
218 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0,
219 "AH transfer mode default level.");
220 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV,
221 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0,
222 "AH tunnel mode default level.");
223 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN,
224 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0,
225 "Explicit Congestion Notification handling.");
226 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW,
227 &VNET_NAME(ipsec_debug), 0,
228 "Enable IPsec debugging output when set.");
229 SYSCTL_VNET_STRUCT(_net_inet6_ipsec6, IPSECCTL_STATS,
230 ipsecstats, CTLFLAG_RD, &VNET_NAME(ipsec6stat), ipsecstat,
231 "IPsec IPv6 statistics.");
232 #endif /* INET6 */
233
234 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *));
235 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int));
236 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int));
237 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *));
238 #ifdef INET6
239 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int));
240 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *));
241 #endif
242 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *));
243 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src));
244 static void vshiftl __P((unsigned char *, int, int));
245
246 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy");
247
248 /*
249 * Return a held reference to the default SP.
250 */
251 static struct secpolicy *
252 key_allocsp_default(const char* where, int tag)
253 {
254 struct secpolicy *sp;
255
256 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
257 printf("DP key_allocsp_default from %s:%u\n", where, tag));
258
259 sp = &V_ip4_def_policy;
260 if (sp->policy != IPSEC_POLICY_DISCARD &&
261 sp->policy != IPSEC_POLICY_NONE) {
262 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n",
263 sp->policy, IPSEC_POLICY_NONE));
264 sp->policy = IPSEC_POLICY_NONE;
265 }
266 key_addref(sp);
267
268 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
269 printf("DP key_allocsp_default returns SP:%p (%u)\n",
270 sp, sp->refcnt));
271 return (sp);
272 }
273 #define KEY_ALLOCSP_DEFAULT() \
274 key_allocsp_default(__FILE__, __LINE__)
275
276 /*
277 * For OUTBOUND packet having a socket. Searching SPD for packet,
278 * and return a pointer to SP.
279 * OUT: NULL: no apropreate SP found, the following value is set to error.
280 * 0 : bypass
281 * EACCES : discard packet.
282 * ENOENT : ipsec_acquire() in progress, maybe.
283 * others : error occured.
284 * others: a pointer to SP
285 *
286 * NOTE: IPv6 mapped adddress concern is implemented here.
287 */
288 struct secpolicy *
289 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir)
290 {
291 struct secpolicy *sp;
292
293 IPSEC_ASSERT(tdbi != NULL, ("null tdbi"));
294 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
295 ("invalid direction %u", dir));
296
297 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir);
298 if (sp == NULL) /*XXX????*/
299 sp = KEY_ALLOCSP_DEFAULT();
300 IPSEC_ASSERT(sp != NULL, ("null SP"));
301 return (sp);
302 }
303
304 /*
305 * For OUTBOUND packet having a socket. Searching SPD for packet,
306 * and return a pointer to SP.
307 * OUT: NULL: no apropreate SP found, the following value is set to error.
308 * 0 : bypass
309 * EACCES : discard packet.
310 * ENOENT : ipsec_acquire() in progress, maybe.
311 * others : error occured.
312 * others: a pointer to SP
313 *
314 * NOTE: IPv6 mapped adddress concern is implemented here.
315 */
316 static struct secpolicy *
317 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error)
318 {
319 struct inpcbpolicy *pcbsp;
320 struct secpolicy *currsp = NULL; /* Policy on socket. */
321 struct secpolicy *sp;
322
323 IPSEC_ASSERT(m != NULL, ("null mbuf"));
324 IPSEC_ASSERT(inp != NULL, ("null inpcb"));
325 IPSEC_ASSERT(error != NULL, ("null error"));
326 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
327 ("invalid direction %u", dir));
328
329 /* Set spidx in pcb. */
330 *error = ipsec_setspidx_inpcb(m, inp);
331 if (*error)
332 return (NULL);
333
334 pcbsp = inp->inp_sp;
335 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp"));
336 switch (dir) {
337 case IPSEC_DIR_INBOUND:
338 currsp = pcbsp->sp_in;
339 break;
340 case IPSEC_DIR_OUTBOUND:
341 currsp = pcbsp->sp_out;
342 break;
343 }
344 IPSEC_ASSERT(currsp != NULL, ("null currsp"));
345
346 if (pcbsp->priv) { /* When privilieged socket. */
347 switch (currsp->policy) {
348 case IPSEC_POLICY_BYPASS:
349 case IPSEC_POLICY_IPSEC:
350 key_addref(currsp);
351 sp = currsp;
352 break;
353
354 case IPSEC_POLICY_ENTRUST:
355 /* Look for a policy in SPD. */
356 sp = KEY_ALLOCSP(&currsp->spidx, dir);
357 if (sp == NULL) /* No SP found. */
358 sp = KEY_ALLOCSP_DEFAULT();
359 break;
360
361 default:
362 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n",
363 __func__, currsp->policy));
364 *error = EINVAL;
365 return (NULL);
366 }
367 } else { /* Unpriv, SPD has policy. */
368 sp = KEY_ALLOCSP(&currsp->spidx, dir);
369 if (sp == NULL) { /* No SP found. */
370 switch (currsp->policy) {
371 case IPSEC_POLICY_BYPASS:
372 ipseclog((LOG_ERR, "%s: Illegal policy for "
373 "non-priviliged defined %d\n",
374 __func__, currsp->policy));
375 *error = EINVAL;
376 return (NULL);
377
378 case IPSEC_POLICY_ENTRUST:
379 sp = KEY_ALLOCSP_DEFAULT();
380 break;
381
382 case IPSEC_POLICY_IPSEC:
383 key_addref(currsp);
384 sp = currsp;
385 break;
386
387 default:
388 ipseclog((LOG_ERR, "%s: Invalid policy for "
389 "PCB %d\n", __func__, currsp->policy));
390 *error = EINVAL;
391 return (NULL);
392 }
393 }
394 }
395 IPSEC_ASSERT(sp != NULL,
396 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy));
397 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
398 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n",
399 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt));
400 return (sp);
401 }
402
403 /*
404 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet,
405 * and return a pointer to SP.
406 * OUT: positive: a pointer to the entry for security policy leaf matched.
407 * NULL: no apropreate SP found, the following value is set to error.
408 * 0 : bypass
409 * EACCES : discard packet.
410 * ENOENT : ipsec_acquire() in progress, maybe.
411 * others : error occured.
412 */
413 struct secpolicy *
414 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error)
415 {
416 struct secpolicyindex spidx;
417 struct secpolicy *sp;
418
419 IPSEC_ASSERT(m != NULL, ("null mbuf"));
420 IPSEC_ASSERT(error != NULL, ("null error"));
421 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
422 ("invalid direction %u", dir));
423
424 sp = NULL;
425 if (key_havesp(dir)) {
426 /* Make an index to look for a policy. */
427 *error = ipsec_setspidx(m, &spidx,
428 (flag & IP_FORWARDING) ? 0 : 1);
429 if (*error != 0) {
430 DPRINTF(("%s: setpidx failed, dir %u flag %u\n",
431 __func__, dir, flag));
432 return (NULL);
433 }
434 spidx.dir = dir;
435
436 sp = KEY_ALLOCSP(&spidx, dir);
437 }
438 if (sp == NULL) /* No SP found, use system default. */
439 sp = KEY_ALLOCSP_DEFAULT();
440 IPSEC_ASSERT(sp != NULL, ("null SP"));
441 return (sp);
442 }
443
444 struct secpolicy *
445 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error,
446 struct inpcb *inp)
447 {
448 struct secpolicy *sp;
449
450 *error = 0;
451 if (inp == NULL)
452 sp = ipsec_getpolicybyaddr(m, dir, flag, error);
453 else
454 sp = ipsec_getpolicybysock(m, dir, inp, error);
455 if (sp == NULL) {
456 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error"));
457 IPSECSTAT_INC(ips_out_inval);
458 return (NULL);
459 }
460 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error));
461 switch (sp->policy) {
462 case IPSEC_POLICY_ENTRUST:
463 default:
464 printf("%s: invalid policy %u\n", __func__, sp->policy);
465 /* FALLTHROUGH */
466 case IPSEC_POLICY_DISCARD:
467 IPSECSTAT_INC(ips_out_polvio);
468 *error = -EINVAL; /* Packet is discarded by caller. */
469 break;
470 case IPSEC_POLICY_BYPASS:
471 case IPSEC_POLICY_NONE:
472 KEY_FREESP(&sp);
473 sp = NULL; /* NB: force NULL result. */
474 break;
475 case IPSEC_POLICY_IPSEC:
476 if (sp->req == NULL) /* Acquire a SA. */
477 *error = key_spdacquire(sp);
478 break;
479 }
480 if (*error != 0) {
481 KEY_FREESP(&sp);
482 sp = NULL;
483 }
484 return (sp);
485 }
486
487 static int
488 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp)
489 {
490 int error;
491
492 IPSEC_ASSERT(inp != NULL, ("null inp"));
493 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
494 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL,
495 ("null sp_in || sp_out"));
496
497 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1);
498 if (error == 0) {
499 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND;
500 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx;
501 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND;
502 } else {
503 bzero(&inp->inp_sp->sp_in->spidx,
504 sizeof (inp->inp_sp->sp_in->spidx));
505 bzero(&inp->inp_sp->sp_out->spidx,
506 sizeof (inp->inp_sp->sp_in->spidx));
507 }
508 return (error);
509 }
510
511 /*
512 * Configure security policy index (src/dst/proto/sport/dport)
513 * by looking at the content of mbuf.
514 * The caller is responsible for error recovery (like clearing up spidx).
515 */
516 static int
517 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport)
518 {
519 struct ip *ip = NULL;
520 struct ip ipbuf;
521 u_int v;
522 struct mbuf *n;
523 int len;
524 int error;
525
526 IPSEC_ASSERT(m != NULL, ("null mbuf"));
527
528 /*
529 * Validate m->m_pkthdr.len. We see incorrect length if we
530 * mistakenly call this function with inconsistent mbuf chain
531 * (like 4.4BSD tcp/udp processing). XXX Should we panic here?
532 */
533 len = 0;
534 for (n = m; n; n = n->m_next)
535 len += n->m_len;
536 if (m->m_pkthdr.len != len) {
537 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
538 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n",
539 __func__, len, m->m_pkthdr.len));
540 return (EINVAL);
541 }
542
543 if (m->m_pkthdr.len < sizeof(struct ip)) {
544 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
545 printf("%s: pkthdr len(%d) too small (v4), ignored.\n",
546 __func__, m->m_pkthdr.len));
547 return (EINVAL);
548 }
549
550 if (m->m_len >= sizeof(*ip))
551 ip = mtod(m, struct ip *);
552 else {
553 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf);
554 ip = &ipbuf;
555 }
556 #ifdef _IP_VHL
557 v = _IP_VHL_V(ip->ip_vhl);
558 #else
559 v = ip->ip_v;
560 #endif
561 switch (v) {
562 case 4:
563 error = ipsec4_setspidx_ipaddr(m, spidx);
564 if (error)
565 return (error);
566 ipsec4_get_ulp(m, spidx, needport);
567 return (0);
568 #ifdef INET6
569 case 6:
570 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) {
571 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
572 printf("%s: pkthdr len(%d) too small (v6), "
573 "ignored\n", __func__, m->m_pkthdr.len));
574 return (EINVAL);
575 }
576 error = ipsec6_setspidx_ipaddr(m, spidx);
577 if (error)
578 return (error);
579 ipsec6_get_ulp(m, spidx, needport);
580 return (0);
581 #endif
582 default:
583 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
584 printf("%s: " "unknown IP version %u, ignored.\n",
585 __func__, v));
586 return (EINVAL);
587 }
588 }
589
590 static void
591 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
592 {
593 u_int8_t nxt;
594 int off;
595
596 /* Sanity check. */
597 IPSEC_ASSERT(m != NULL, ("null mbuf"));
598 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short"));
599
600 /* NB: ip_input() flips it into host endian. XXX Need more checking. */
601 if (m->m_len >= sizeof (struct ip)) {
602 struct ip *ip = mtod(m, struct ip *);
603 if (ip->ip_off & (IP_MF | IP_OFFMASK))
604 goto done;
605 #ifdef _IP_VHL
606 off = _IP_VHL_HL(ip->ip_vhl) << 2;
607 #else
608 off = ip->ip_hl << 2;
609 #endif
610 nxt = ip->ip_p;
611 } else {
612 struct ip ih;
613
614 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih);
615 if (ih.ip_off & (IP_MF | IP_OFFMASK))
616 goto done;
617 #ifdef _IP_VHL
618 off = _IP_VHL_HL(ih.ip_vhl) << 2;
619 #else
620 off = ih.ip_hl << 2;
621 #endif
622 nxt = ih.ip_p;
623 }
624
625 while (off < m->m_pkthdr.len) {
626 struct ip6_ext ip6e;
627 struct tcphdr th;
628 struct udphdr uh;
629
630 switch (nxt) {
631 case IPPROTO_TCP:
632 spidx->ul_proto = nxt;
633 if (!needport)
634 goto done_proto;
635 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
636 goto done;
637 m_copydata(m, off, sizeof (th), (caddr_t) &th);
638 spidx->src.sin.sin_port = th.th_sport;
639 spidx->dst.sin.sin_port = th.th_dport;
640 return;
641 case IPPROTO_UDP:
642 spidx->ul_proto = nxt;
643 if (!needport)
644 goto done_proto;
645 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
646 goto done;
647 m_copydata(m, off, sizeof (uh), (caddr_t) &uh);
648 spidx->src.sin.sin_port = uh.uh_sport;
649 spidx->dst.sin.sin_port = uh.uh_dport;
650 return;
651 case IPPROTO_AH:
652 if (off + sizeof(ip6e) > m->m_pkthdr.len)
653 goto done;
654 /* XXX Sigh, this works but is totally bogus. */
655 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e);
656 off += (ip6e.ip6e_len + 2) << 2;
657 nxt = ip6e.ip6e_nxt;
658 break;
659 case IPPROTO_ICMP:
660 default:
661 /* XXX Intermediate headers??? */
662 spidx->ul_proto = nxt;
663 goto done_proto;
664 }
665 }
666 done:
667 spidx->ul_proto = IPSEC_ULPROTO_ANY;
668 done_proto:
669 spidx->src.sin.sin_port = IPSEC_PORT_ANY;
670 spidx->dst.sin.sin_port = IPSEC_PORT_ANY;
671 }
672
673 /* Assumes that m is sane. */
674 static int
675 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
676 {
677 static const struct sockaddr_in template = {
678 sizeof (struct sockaddr_in),
679 AF_INET,
680 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 }
681 };
682
683 spidx->src.sin = template;
684 spidx->dst.sin = template;
685
686 if (m->m_len < sizeof (struct ip)) {
687 m_copydata(m, offsetof(struct ip, ip_src),
688 sizeof (struct in_addr),
689 (caddr_t) &spidx->src.sin.sin_addr);
690 m_copydata(m, offsetof(struct ip, ip_dst),
691 sizeof (struct in_addr),
692 (caddr_t) &spidx->dst.sin.sin_addr);
693 } else {
694 struct ip *ip = mtod(m, struct ip *);
695 spidx->src.sin.sin_addr = ip->ip_src;
696 spidx->dst.sin.sin_addr = ip->ip_dst;
697 }
698
699 spidx->prefs = sizeof(struct in_addr) << 3;
700 spidx->prefd = sizeof(struct in_addr) << 3;
701
702 return (0);
703 }
704
705 #ifdef INET6
706 static void
707 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
708 {
709 int off, nxt;
710 struct tcphdr th;
711 struct udphdr uh;
712 struct icmp6_hdr ih;
713
714 /* Sanity check. */
715 if (m == NULL)
716 panic("%s: NULL pointer was passed.\n", __func__);
717
718 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
719 printf("%s:\n", __func__); kdebug_mbuf(m));
720
721 /* Set default. */
722 spidx->ul_proto = IPSEC_ULPROTO_ANY;
723 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY;
724 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY;
725
726 nxt = -1;
727 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
728 if (off < 0 || m->m_pkthdr.len < off)
729 return;
730
731 switch (nxt) {
732 case IPPROTO_TCP:
733 spidx->ul_proto = nxt;
734 if (!needport)
735 break;
736 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
737 break;
738 m_copydata(m, off, sizeof(th), (caddr_t)&th);
739 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport;
740 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport;
741 break;
742 case IPPROTO_UDP:
743 spidx->ul_proto = nxt;
744 if (!needport)
745 break;
746 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
747 break;
748 m_copydata(m, off, sizeof(uh), (caddr_t)&uh);
749 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport;
750 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport;
751 break;
752 case IPPROTO_ICMPV6:
753 spidx->ul_proto = nxt;
754 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len)
755 break;
756 m_copydata(m, off, sizeof(ih), (caddr_t)&ih);
757 ((struct sockaddr_in6 *)&spidx->src)->sin6_port =
758 htons((uint16_t)ih.icmp6_type);
759 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port =
760 htons((uint16_t)ih.icmp6_code);
761 break;
762 default:
763 /* XXX Intermediate headers??? */
764 spidx->ul_proto = nxt;
765 break;
766 }
767 }
768
769 /* Assumes that m is sane. */
770 static int
771 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
772 {
773 struct ip6_hdr *ip6 = NULL;
774 struct ip6_hdr ip6buf;
775 struct sockaddr_in6 *sin6;
776
777 if (m->m_len >= sizeof(*ip6))
778 ip6 = mtod(m, struct ip6_hdr *);
779 else {
780 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf);
781 ip6 = &ip6buf;
782 }
783
784 sin6 = (struct sockaddr_in6 *)&spidx->src;
785 bzero(sin6, sizeof(*sin6));
786 sin6->sin6_family = AF_INET6;
787 sin6->sin6_len = sizeof(struct sockaddr_in6);
788 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src));
789 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
790 sin6->sin6_addr.s6_addr16[1] = 0;
791 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]);
792 }
793 spidx->prefs = sizeof(struct in6_addr) << 3;
794
795 sin6 = (struct sockaddr_in6 *)&spidx->dst;
796 bzero(sin6, sizeof(*sin6));
797 sin6->sin6_family = AF_INET6;
798 sin6->sin6_len = sizeof(struct sockaddr_in6);
799 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst));
800 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
801 sin6->sin6_addr.s6_addr16[1] = 0;
802 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
803 }
804 spidx->prefd = sizeof(struct in6_addr) << 3;
805
806 return (0);
807 }
808 #endif
809
810 static void
811 ipsec_delpcbpolicy(struct inpcbpolicy *p)
812 {
813
814 free(p, M_IPSEC_INPCB);
815 }
816
817 /* Initialize policy in PCB. */
818 int
819 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp)
820 {
821 struct inpcbpolicy *new;
822
823 /* Sanity check. */
824 if (so == NULL || pcb_sp == NULL)
825 panic("%s: NULL pointer was passed.\n", __func__);
826
827 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy),
828 M_IPSEC_INPCB, M_NOWAIT|M_ZERO);
829 if (new == NULL) {
830 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
831 return (ENOBUFS);
832 }
833
834 new->priv = IPSEC_IS_PRIVILEGED_SO(so);
835
836 if ((new->sp_in = KEY_NEWSP()) == NULL) {
837 ipsec_delpcbpolicy(new);
838 return (ENOBUFS);
839 }
840 new->sp_in->state = IPSEC_SPSTATE_ALIVE;
841 new->sp_in->policy = IPSEC_POLICY_ENTRUST;
842
843 if ((new->sp_out = KEY_NEWSP()) == NULL) {
844 KEY_FREESP(&new->sp_in);
845 ipsec_delpcbpolicy(new);
846 return (ENOBUFS);
847 }
848 new->sp_out->state = IPSEC_SPSTATE_ALIVE;
849 new->sp_out->policy = IPSEC_POLICY_ENTRUST;
850
851 *pcb_sp = new;
852
853 return (0);
854 }
855
856 /* Copy old IPsec policy into new. */
857 int
858 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new)
859 {
860 struct secpolicy *sp;
861
862 sp = ipsec_deepcopy_policy(old->sp_in);
863 if (sp) {
864 KEY_FREESP(&new->sp_in);
865 new->sp_in = sp;
866 } else
867 return (ENOBUFS);
868
869 sp = ipsec_deepcopy_policy(old->sp_out);
870 if (sp) {
871 KEY_FREESP(&new->sp_out);
872 new->sp_out = sp;
873 } else
874 return (ENOBUFS);
875
876 new->priv = old->priv;
877
878 return (0);
879 }
880
881 struct ipsecrequest *
882 ipsec_newisr(void)
883 {
884 struct ipsecrequest *p;
885
886 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO);
887 if (p != NULL)
888 IPSECREQUEST_LOCK_INIT(p);
889 return (p);
890 }
891
892 void
893 ipsec_delisr(struct ipsecrequest *p)
894 {
895
896 IPSECREQUEST_LOCK_DESTROY(p);
897 free(p, M_IPSEC_SR);
898 }
899
900 /* Deep-copy a policy in PCB. */
901 static struct secpolicy *
902 ipsec_deepcopy_policy(struct secpolicy *src)
903 {
904 struct ipsecrequest *newchain = NULL;
905 struct ipsecrequest *p;
906 struct ipsecrequest **q;
907 struct ipsecrequest *r;
908 struct secpolicy *dst;
909
910 if (src == NULL)
911 return (NULL);
912 dst = KEY_NEWSP();
913 if (dst == NULL)
914 return (NULL);
915
916 /*
917 * Deep-copy IPsec request chain. This is required since struct
918 * ipsecrequest is not reference counted.
919 */
920 q = &newchain;
921 for (p = src->req; p; p = p->next) {
922 *q = ipsec_newisr();
923 if (*q == NULL)
924 goto fail;
925 (*q)->saidx.proto = p->saidx.proto;
926 (*q)->saidx.mode = p->saidx.mode;
927 (*q)->level = p->level;
928 (*q)->saidx.reqid = p->saidx.reqid;
929
930 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src));
931 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst));
932
933 (*q)->sp = dst;
934
935 q = &((*q)->next);
936 }
937
938 dst->req = newchain;
939 dst->state = src->state;
940 dst->policy = src->policy;
941 /* Do not touch the refcnt fields. */
942
943 return (dst);
944
945 fail:
946 for (p = newchain; p; p = r) {
947 r = p->next;
948 ipsec_delisr(p);
949 p = NULL;
950 }
951 return (NULL);
952 }
953
954 /* Set policy and IPsec request if present. */
955 static int
956 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname,
957 caddr_t request, size_t len, struct ucred *cred)
958 {
959 struct sadb_x_policy *xpl;
960 struct secpolicy *newsp = NULL;
961 int error;
962
963 /* Sanity check. */
964 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL)
965 return (EINVAL);
966 if (len < sizeof(*xpl))
967 return (EINVAL);
968 xpl = (struct sadb_x_policy *)request;
969
970 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
971 printf("%s: passed policy\n", __func__);
972 kdebug_sadb_x_policy((struct sadb_ext *)xpl));
973
974 /* Check policy type. */
975 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */
976 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD
977 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE)
978 return (EINVAL);
979
980 /* Check privileged socket. */
981 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) {
982 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0);
983 if (error)
984 return (EACCES);
985 }
986
987 /* Allocating new SP entry. */
988 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL)
989 return (error);
990
991 newsp->state = IPSEC_SPSTATE_ALIVE;
992
993 /* Clear old SP and set new SP. */
994 KEY_FREESP(pcb_sp);
995 *pcb_sp = newsp;
996 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
997 printf("%s: new policy\n", __func__);
998 kdebug_secpolicy(newsp));
999
1000 return (0);
1001 }
1002
1003 int
1004 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request,
1005 size_t len, struct ucred *cred)
1006 {
1007 struct sadb_x_policy *xpl;
1008 struct secpolicy **pcb_sp;
1009
1010 /* Sanity check. */
1011 if (inp == NULL || request == NULL)
1012 return (EINVAL);
1013 if (len < sizeof(*xpl))
1014 return (EINVAL);
1015 xpl = (struct sadb_x_policy *)request;
1016
1017 /* Select direction. */
1018 switch (xpl->sadb_x_policy_dir) {
1019 case IPSEC_DIR_INBOUND:
1020 pcb_sp = &inp->inp_sp->sp_in;
1021 break;
1022 case IPSEC_DIR_OUTBOUND:
1023 pcb_sp = &inp->inp_sp->sp_out;
1024 break;
1025 default:
1026 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1027 xpl->sadb_x_policy_dir));
1028 return (EINVAL);
1029 }
1030
1031 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred));
1032 }
1033
1034 int
1035 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len,
1036 struct mbuf **mp)
1037 {
1038 struct sadb_x_policy *xpl;
1039 struct secpolicy *pcb_sp;
1040
1041 /* Sanity check. */
1042 if (inp == NULL || request == NULL || mp == NULL)
1043 return (EINVAL);
1044 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
1045 if (len < sizeof(*xpl))
1046 return (EINVAL);
1047 xpl = (struct sadb_x_policy *)request;
1048
1049 /* Select direction. */
1050 switch (xpl->sadb_x_policy_dir) {
1051 case IPSEC_DIR_INBOUND:
1052 pcb_sp = inp->inp_sp->sp_in;
1053 break;
1054 case IPSEC_DIR_OUTBOUND:
1055 pcb_sp = inp->inp_sp->sp_out;
1056 break;
1057 default:
1058 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1059 xpl->sadb_x_policy_dir));
1060 return (EINVAL);
1061 }
1062
1063 /* Sanity check. Should be an IPSEC_ASSERT. */
1064 if (pcb_sp == NULL)
1065 return (EINVAL);
1066
1067 *mp = key_sp2msg(pcb_sp);
1068 if (!*mp) {
1069 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
1070 return (ENOBUFS);
1071 }
1072
1073 (*mp)->m_type = MT_DATA;
1074 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1075 printf("%s:\n", __func__); kdebug_mbuf(*mp));
1076
1077 return (0);
1078 }
1079
1080 /* Delete policy in PCB. */
1081 int
1082 ipsec_delete_pcbpolicy(struct inpcb *inp)
1083 {
1084 IPSEC_ASSERT(inp != NULL, ("null inp"));
1085
1086 if (inp->inp_sp == NULL)
1087 return (0);
1088
1089 if (inp->inp_sp->sp_in != NULL)
1090 KEY_FREESP(&inp->inp_sp->sp_in);
1091
1092 if (inp->inp_sp->sp_out != NULL)
1093 KEY_FREESP(&inp->inp_sp->sp_out);
1094
1095 ipsec_delpcbpolicy(inp->inp_sp);
1096 inp->inp_sp = NULL;
1097
1098 return (0);
1099 }
1100
1101 /*
1102 * Return current level.
1103 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned.
1104 */
1105 u_int
1106 ipsec_get_reqlevel(struct ipsecrequest *isr)
1107 {
1108 u_int level = 0;
1109 u_int esp_trans_deflev, esp_net_deflev;
1110 u_int ah_trans_deflev, ah_net_deflev;
1111
1112 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument"));
1113 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family,
1114 ("af family mismatch, src %u, dst %u",
1115 isr->sp->spidx.src.sa.sa_family,
1116 isr->sp->spidx.dst.sa.sa_family));
1117
1118 /* XXX Note that we have ipseclog() expanded here - code sync issue. */
1119 #define IPSEC_CHECK_DEFAULT(lev) \
1120 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \
1121 && (lev) != IPSEC_LEVEL_UNIQUE) \
1122 ? (V_ipsec_debug \
1123 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\
1124 (lev), IPSEC_LEVEL_REQUIRE) \
1125 : 0), \
1126 (lev) = IPSEC_LEVEL_REQUIRE, \
1127 (lev) \
1128 : (lev))
1129
1130 /* Set default level. */
1131 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) {
1132 #ifdef INET
1133 case AF_INET:
1134 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev);
1135 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev);
1136 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev);
1137 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev);
1138 break;
1139 #endif
1140 #ifdef INET6
1141 case AF_INET6:
1142 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev);
1143 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev);
1144 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev);
1145 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev);
1146 break;
1147 #endif /* INET6 */
1148 default:
1149 panic("%s: unknown af %u",
1150 __func__, isr->sp->spidx.src.sa.sa_family);
1151 }
1152
1153 #undef IPSEC_CHECK_DEFAULT
1154
1155 /* Set level. */
1156 switch (isr->level) {
1157 case IPSEC_LEVEL_DEFAULT:
1158 switch (isr->saidx.proto) {
1159 case IPPROTO_ESP:
1160 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1161 level = esp_net_deflev;
1162 else
1163 level = esp_trans_deflev;
1164 break;
1165 case IPPROTO_AH:
1166 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1167 level = ah_net_deflev;
1168 else
1169 level = ah_trans_deflev;
1170 break;
1171 case IPPROTO_IPCOMP:
1172 /*
1173 * We don't really care, as IPcomp document says that
1174 * we shouldn't compress small packets.
1175 */
1176 level = IPSEC_LEVEL_USE;
1177 break;
1178 default:
1179 panic("%s: Illegal protocol defined %u\n", __func__,
1180 isr->saidx.proto);
1181 }
1182 break;
1183
1184 case IPSEC_LEVEL_USE:
1185 case IPSEC_LEVEL_REQUIRE:
1186 level = isr->level;
1187 break;
1188 case IPSEC_LEVEL_UNIQUE:
1189 level = IPSEC_LEVEL_REQUIRE;
1190 break;
1191
1192 default:
1193 panic("%s: Illegal IPsec level %u\n", __func__, isr->level);
1194 }
1195
1196 return (level);
1197 }
1198
1199 /*
1200 * Check security policy requirements against the actual
1201 * packet contents. Return one if the packet should be
1202 * reject as "invalid"; otherwiser return zero to have the
1203 * packet treated as "valid".
1204 *
1205 * OUT:
1206 * 0: valid
1207 * 1: invalid
1208 */
1209 int
1210 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m)
1211 {
1212 struct ipsecrequest *isr;
1213 int need_auth;
1214
1215 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1216 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1217
1218 /* Check policy. */
1219 switch (sp->policy) {
1220 case IPSEC_POLICY_DISCARD:
1221 return (1);
1222 case IPSEC_POLICY_BYPASS:
1223 case IPSEC_POLICY_NONE:
1224 return (0);
1225 }
1226
1227 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1228 ("invalid policy %u", sp->policy));
1229
1230 /* XXX Should compare policy against IPsec header history. */
1231
1232 need_auth = 0;
1233 for (isr = sp->req; isr != NULL; isr = isr->next) {
1234 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE)
1235 continue;
1236 switch (isr->saidx.proto) {
1237 case IPPROTO_ESP:
1238 if ((m->m_flags & M_DECRYPTED) == 0) {
1239 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1240 printf("%s: ESP m_flags:%x\n", __func__,
1241 m->m_flags));
1242 return (1);
1243 }
1244
1245 if (!need_auth &&
1246 isr->sav != NULL &&
1247 isr->sav->tdb_authalgxform != NULL &&
1248 (m->m_flags & M_AUTHIPDGM) == 0) {
1249 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1250 printf("%s: ESP/AH m_flags:%x\n", __func__,
1251 m->m_flags));
1252 return (1);
1253 }
1254 break;
1255 case IPPROTO_AH:
1256 need_auth = 1;
1257 if ((m->m_flags & M_AUTHIPHDR) == 0) {
1258 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1259 printf("%s: AH m_flags:%x\n", __func__,
1260 m->m_flags));
1261 return (1);
1262 }
1263 break;
1264 case IPPROTO_IPCOMP:
1265 /*
1266 * We don't really care, as IPcomp document
1267 * says that we shouldn't compress small
1268 * packets. IPComp policy should always be
1269 * treated as being in "use" level.
1270 */
1271 break;
1272 }
1273 }
1274 return (0); /* Valid. */
1275 }
1276
1277 static int
1278 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp)
1279 {
1280 struct secpolicy *sp;
1281 int error;
1282 int result;
1283
1284 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1285
1286 /*
1287 * Get SP for this packet.
1288 * When we are called from ip_forward(), we call
1289 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1290 */
1291 if (inp == NULL)
1292 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error);
1293 else
1294 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error);
1295
1296 if (sp != NULL) {
1297 result = ipsec_in_reject(sp, m);
1298 KEY_FREESP(&sp);
1299 } else {
1300 result = 0; /* XXX Should be panic?
1301 * -> No, there may be error. */
1302 }
1303 return (result);
1304 }
1305
1306 /*
1307 * Check AH/ESP integrity.
1308 * This function is called from tcp_input(), udp_input(),
1309 * and {ah,esp}4_input for tunnel mode.
1310 */
1311 int
1312 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp)
1313 {
1314 int result;
1315
1316 result = ipsec46_in_reject(m, inp);
1317 if (result)
1318 IPSECSTAT_INC(ips_in_polvio);
1319
1320 return (result);
1321 }
1322
1323 #ifdef INET6
1324 /*
1325 * Check AH/ESP integrity.
1326 * This function is called from tcp6_input(), udp6_input(),
1327 * and {ah,esp}6_input for tunnel mode.
1328 */
1329 int
1330 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp)
1331 {
1332 int result;
1333
1334 result = ipsec46_in_reject(m, inp);
1335 if (result)
1336 IPSEC6STAT_INC(ips_in_polvio);
1337
1338 return (result);
1339 }
1340 #endif
1341
1342 /*
1343 * Compute the byte size to be occupied by IPsec header.
1344 * In case it is tunnelled, it includes the size of outer IP header.
1345 * NOTE: SP passed is freed in this function.
1346 */
1347 static size_t
1348 ipsec_hdrsiz_internal(struct secpolicy *sp)
1349 {
1350 struct ipsecrequest *isr;
1351 size_t size;
1352
1353 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1354 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1355
1356 switch (sp->policy) {
1357 case IPSEC_POLICY_DISCARD:
1358 case IPSEC_POLICY_BYPASS:
1359 case IPSEC_POLICY_NONE:
1360 return (0);
1361 }
1362
1363 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1364 ("invalid policy %u", sp->policy));
1365
1366 size = 0;
1367 for (isr = sp->req; isr != NULL; isr = isr->next) {
1368 size_t clen = 0;
1369
1370 switch (isr->saidx.proto) {
1371 case IPPROTO_ESP:
1372 clen = esp_hdrsiz(isr->sav);
1373 break;
1374 case IPPROTO_AH:
1375 clen = ah_hdrsiz(isr->sav);
1376 break;
1377 case IPPROTO_IPCOMP:
1378 clen = sizeof(struct ipcomp);
1379 break;
1380 }
1381
1382 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
1383 switch (isr->saidx.dst.sa.sa_family) {
1384 case AF_INET:
1385 clen += sizeof(struct ip);
1386 break;
1387 #ifdef INET6
1388 case AF_INET6:
1389 clen += sizeof(struct ip6_hdr);
1390 break;
1391 #endif
1392 default:
1393 ipseclog((LOG_ERR, "%s: unknown AF %d in "
1394 "IPsec tunnel SA\n", __func__,
1395 ((struct sockaddr *)&isr->saidx.dst)->sa_family));
1396 break;
1397 }
1398 }
1399 size += clen;
1400 }
1401
1402 return (size);
1403 }
1404
1405 /*
1406 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(),
1407 * disabled ip6_ipsec_mtu() and ip6_forward().
1408 */
1409 size_t
1410 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp)
1411 {
1412 struct secpolicy *sp;
1413 int error;
1414 size_t size;
1415
1416 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1417
1418 /* Get SP for this packet.
1419 * When we are called from ip_forward(), we call
1420 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1421 */
1422 if (inp == NULL)
1423 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error);
1424 else
1425 sp = ipsec_getpolicybysock(m, dir, inp, &error);
1426
1427 if (sp != NULL) {
1428 size = ipsec_hdrsiz_internal(sp);
1429 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1430 printf("%s: size:%lu.\n", __func__,
1431 (unsigned long)size));
1432
1433 KEY_FREESP(&sp);
1434 } else {
1435 size = 0; /* XXX Should be panic?
1436 * -> No, we are called w/o knowing if
1437 * IPsec processing is needed. */
1438 }
1439 return (size);
1440 }
1441
1442 /*
1443 * Check the variable replay window.
1444 * ipsec_chkreplay() performs replay check before ICV verification.
1445 * ipsec_updatereplay() updates replay bitmap. This must be called after
1446 * ICV verification (it also performs replay check, which is usually done
1447 * beforehand).
1448 * 0 (zero) is returned if packet disallowed, 1 if packet permitted.
1449 *
1450 * Based on RFC 2401.
1451 */
1452 int
1453 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav)
1454 {
1455 const struct secreplay *replay;
1456 u_int32_t diff;
1457 int fr;
1458 u_int32_t wsizeb; /* Constant: bits of window size. */
1459 int frlast; /* Constant: last frame. */
1460
1461 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1462 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1463
1464 replay = sav->replay;
1465
1466 if (replay->wsize == 0)
1467 return (1); /* No need to check replay. */
1468
1469 /* Constant. */
1470 frlast = replay->wsize - 1;
1471 wsizeb = replay->wsize << 3;
1472
1473 /* Sequence number of 0 is invalid. */
1474 if (seq == 0)
1475 return (0);
1476
1477 /* First time is always okay. */
1478 if (replay->count == 0)
1479 return (1);
1480
1481 if (seq > replay->lastseq) {
1482 /* Larger sequences are okay. */
1483 return (1);
1484 } else {
1485 /* seq is equal or less than lastseq. */
1486 diff = replay->lastseq - seq;
1487
1488 /* Over range to check, i.e. too old or wrapped. */
1489 if (diff >= wsizeb)
1490 return (0);
1491
1492 fr = frlast - diff / 8;
1493
1494 /* This packet already seen? */
1495 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1496 return (0);
1497
1498 /* Out of order but good. */
1499 return (1);
1500 }
1501 }
1502
1503 /*
1504 * Check replay counter whether to update or not.
1505 * OUT: 0: OK
1506 * 1: NG
1507 */
1508 int
1509 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav)
1510 {
1511 struct secreplay *replay;
1512 u_int32_t diff;
1513 int fr;
1514 u_int32_t wsizeb; /* Constant: bits of window size. */
1515 int frlast; /* Constant: last frame. */
1516
1517 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1518 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1519
1520 replay = sav->replay;
1521
1522 if (replay->wsize == 0)
1523 goto ok; /* No need to check replay. */
1524
1525 /* Constant. */
1526 frlast = replay->wsize - 1;
1527 wsizeb = replay->wsize << 3;
1528
1529 /* Sequence number of 0 is invalid. */
1530 if (seq == 0)
1531 return (1);
1532
1533 /* First time. */
1534 if (replay->count == 0) {
1535 replay->lastseq = seq;
1536 bzero(replay->bitmap, replay->wsize);
1537 (replay->bitmap)[frlast] = 1;
1538 goto ok;
1539 }
1540
1541 if (seq > replay->lastseq) {
1542 /* seq is larger than lastseq. */
1543 diff = seq - replay->lastseq;
1544
1545 /* New larger sequence number. */
1546 if (diff < wsizeb) {
1547 /* In window. */
1548 /* Set bit for this packet. */
1549 vshiftl(replay->bitmap, diff, replay->wsize);
1550 (replay->bitmap)[frlast] |= 1;
1551 } else {
1552 /* This packet has a "way larger". */
1553 bzero(replay->bitmap, replay->wsize);
1554 (replay->bitmap)[frlast] = 1;
1555 }
1556 replay->lastseq = seq;
1557
1558 /* Larger is good. */
1559 } else {
1560 /* seq is equal or less than lastseq. */
1561 diff = replay->lastseq - seq;
1562
1563 /* Over range to check, i.e. too old or wrapped. */
1564 if (diff >= wsizeb)
1565 return (1);
1566
1567 fr = frlast - diff / 8;
1568
1569 /* This packet already seen? */
1570 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1571 return (1);
1572
1573 /* Mark as seen. */
1574 (replay->bitmap)[fr] |= (1 << (diff % 8));
1575
1576 /* Out of order but good. */
1577 }
1578
1579 ok:
1580 if (replay->count == ~0) {
1581
1582 /* Set overflow flag. */
1583 replay->overflow++;
1584
1585 /* Don't increment, no more packets accepted. */
1586 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0)
1587 return (1);
1588
1589 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n",
1590 __func__, replay->overflow, ipsec_logsastr(sav)));
1591 }
1592
1593 replay->count++;
1594
1595 return (0);
1596 }
1597
1598 /*
1599 * Shift variable length buffer to left.
1600 * IN: bitmap: pointer to the buffer
1601 * nbit: the number of to shift.
1602 * wsize: buffer size (bytes).
1603 */
1604 static void
1605 vshiftl(unsigned char *bitmap, int nbit, int wsize)
1606 {
1607 int s, j, i;
1608 unsigned char over;
1609
1610 for (j = 0; j < nbit; j += 8) {
1611 s = (nbit - j < 8) ? (nbit - j): 8;
1612 bitmap[0] <<= s;
1613 for (i = 1; i < wsize; i++) {
1614 over = (bitmap[i] >> (8 - s));
1615 bitmap[i] <<= s;
1616 bitmap[i-1] |= over;
1617 }
1618 }
1619 }
1620
1621 #ifdef INET
1622 /* Return a printable string for the IPv4 address. */
1623 static char *
1624 inet_ntoa4(struct in_addr ina)
1625 {
1626 static char buf[4][4 * sizeof "123" + 4];
1627 unsigned char *ucp = (unsigned char *) &ina;
1628 static int i = 3;
1629
1630 /* XXX-BZ Returns static buffer. */
1631 i = (i + 1) % 4;
1632 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff,
1633 ucp[2] & 0xff, ucp[3] & 0xff);
1634 return (buf[i]);
1635 }
1636 #endif
1637
1638 /* Return a printable string for the address. */
1639 char *
1640 ipsec_address(union sockaddr_union* sa)
1641 {
1642 #ifdef INET6
1643 char ip6buf[INET6_ADDRSTRLEN];
1644 #endif
1645
1646 switch (sa->sa.sa_family) {
1647 #ifdef INET
1648 case AF_INET:
1649 return (inet_ntoa4(sa->sin.sin_addr));
1650 #endif /* INET */
1651 #ifdef INET6
1652 case AF_INET6:
1653 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr));
1654 #endif /* INET6 */
1655 default:
1656 return ("(unknown address family)");
1657 }
1658 }
1659
1660 const char *
1661 ipsec_logsastr(struct secasvar *sav)
1662 {
1663 static char buf[256];
1664 char *p;
1665 struct secasindex *saidx = &sav->sah->saidx;
1666
1667 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family,
1668 ("address family mismatch"));
1669
1670 p = buf;
1671 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi));
1672 while (p && *p)
1673 p++;
1674 /* NB: only use ipsec_address on one address at a time. */
1675 snprintf(p, sizeof (buf) - (p - buf), "src=%s ",
1676 ipsec_address(&saidx->src));
1677 while (p && *p)
1678 p++;
1679 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)",
1680 ipsec_address(&saidx->dst));
1681
1682 return (buf);
1683 }
1684
1685 void
1686 ipsec_dumpmbuf(struct mbuf *m)
1687 {
1688 int totlen;
1689 int i;
1690 u_char *p;
1691
1692 totlen = 0;
1693 printf("---\n");
1694 while (m) {
1695 p = mtod(m, u_char *);
1696 for (i = 0; i < m->m_len; i++) {
1697 printf("%02x ", p[i]);
1698 totlen++;
1699 if (totlen % 16 == 0)
1700 printf("\n");
1701 }
1702 m = m->m_next;
1703 }
1704 if (totlen % 16 != 0)
1705 printf("\n");
1706 printf("---\n");
1707 }
1708
1709 static void
1710 ipsec_init(const void *unused __unused)
1711 {
1712
1713 SECPOLICY_LOCK_INIT(&V_ip4_def_policy);
1714 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */
1715 }
1716 VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init,
1717 NULL);
1718
1719
1720 /* XXX This stuff doesn't belong here... */
1721
1722 static struct xformsw* xforms = NULL;
1723
1724 /*
1725 * Register a transform; typically at system startup.
1726 */
1727 void
1728 xform_register(struct xformsw* xsp)
1729 {
1730
1731 xsp->xf_next = xforms;
1732 xforms = xsp;
1733 }
1734
1735 /*
1736 * Initialize transform support in an sav.
1737 */
1738 int
1739 xform_init(struct secasvar *sav, int xftype)
1740 {
1741 struct xformsw *xsp;
1742
1743 if (sav->tdb_xform != NULL) /* Previously initialized. */
1744 return (0);
1745 for (xsp = xforms; xsp; xsp = xsp->xf_next)
1746 if (xsp->xf_type == xftype)
1747 return ((*xsp->xf_init)(sav, xsp));
1748 return (EINVAL);
1749 }
Cache object: 553805606bd682b12b26f4a4c23a57fd
|