1 /* $FreeBSD$ */
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/hhook.h>
52 #include <sys/time.h>
53 #include <sys/kernel.h>
54 #include <sys/syslog.h>
55 #include <sys/sysctl.h>
56 #include <sys/proc.h>
57
58 #include <net/if.h>
59 #include <net/if_enc.h>
60 #include <net/if_var.h>
61 #include <net/vnet.h>
62
63 #include <netinet/in.h>
64 #include <netinet/in_systm.h>
65 #include <netinet/ip.h>
66 #include <netinet/ip_var.h>
67 #include <netinet/in_var.h>
68 #include <netinet/udp.h>
69 #include <netinet/udp_var.h>
70 #include <netinet/tcp.h>
71 #include <netinet/udp.h>
72
73 #include <netinet/ip6.h>
74 #ifdef INET6
75 #include <netinet6/ip6_var.h>
76 #endif
77 #include <netinet/in_pcb.h>
78 #ifdef INET6
79 #include <netinet/icmp6.h>
80 #endif
81
82 #include <sys/types.h>
83 #include <netipsec/ipsec.h>
84 #ifdef INET6
85 #include <netipsec/ipsec6.h>
86 #endif
87 #include <netipsec/ah_var.h>
88 #include <netipsec/esp_var.h>
89 #include <netipsec/ipcomp.h> /*XXX*/
90 #include <netipsec/ipcomp_var.h>
91
92 #include <netipsec/key.h>
93 #include <netipsec/keydb.h>
94 #include <netipsec/key_debug.h>
95
96 #include <netipsec/xform.h>
97
98 #include <machine/in_cksum.h>
99
100 #include <opencrypto/cryptodev.h>
101
102 #ifdef IPSEC_DEBUG
103 VNET_DEFINE(int, ipsec_debug) = 1;
104 #else
105 VNET_DEFINE(int, ipsec_debug) = 0;
106 #endif
107
108 /* NB: name changed so netstat doesn't use it. */
109 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat);
110 VNET_PCPUSTAT_SYSINIT(ipsec4stat);
111
112 #ifdef VIMAGE
113 VNET_PCPUSTAT_SYSUNINIT(ipsec4stat);
114 #endif /* VIMAGE */
115
116 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */
117 /* DF bit on encap. 0: clear 1: set 2: copy */
118 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0;
119 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE;
120 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE;
121 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE;
122 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE;
123 /* ECN ignore(-1)/forbidden(0)/allowed(1) */
124 VNET_DEFINE(int, ip4_ipsec_ecn) = 0;
125 VNET_DEFINE(int, ip4_esp_randpad) = -1;
126
127 static VNET_DEFINE(struct secpolicy, def_policy);
128 #define V_def_policy VNET(def_policy)
129 /*
130 * Crypto support requirements:
131 *
132 * 1 require hardware support
133 * -1 require software support
134 * 0 take anything
135 */
136 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE;
137
138 FEATURE(ipsec, "Internet Protocol Security (IPsec)");
139 #ifdef IPSEC_NAT_T
140 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')");
141 #endif
142
143 SYSCTL_DECL(_net_inet_ipsec);
144
145 /* net.inet.ipsec */
146 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy,
147 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(def_policy).policy, 0,
148 "IPsec default policy.");
149 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
150 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0,
151 "Default ESP transport mode level");
152 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
153 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0,
154 "Default ESP tunnel mode level.");
155 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
156 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0,
157 "AH transfer mode default level.");
158 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
159 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0,
160 "AH tunnel mode default level.");
161 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos,
162 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0,
163 "If set clear type-of-service field when doing AH computation.");
164 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask,
165 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0,
166 "If not set clear offset field mask when doing AH computation.");
167 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit,
168 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0,
169 "Do not fragment bit on encap.");
170 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn,
171 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0,
172 "Explicit Congestion Notification handling.");
173 SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug,
174 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0,
175 "Enable IPsec debugging output when set.");
176 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, crypto_support,
177 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(crypto_support), 0,
178 "Crypto driver selection.");
179 SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat,
180 ipsec4stat, "IPsec IPv4 statistics.");
181
182 #ifdef REGRESSION
183 /*
184 * When set to 1, IPsec will send packets with the same sequence number.
185 * This allows to verify if the other side has proper replay attacks detection.
186 */
187 VNET_DEFINE(int, ipsec_replay) = 0;
188 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay,
189 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0,
190 "Emulate replay attack");
191 /*
192 * When set 1, IPsec will send packets with corrupted HMAC.
193 * This allows to verify if the other side properly detects modified packets.
194 */
195 VNET_DEFINE(int, ipsec_integrity) = 0;
196 SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity,
197 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0,
198 "Emulate man-in-the-middle attack");
199 #endif
200
201 #ifdef INET6
202 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat);
203 VNET_PCPUSTAT_SYSINIT(ipsec6stat);
204
205 #ifdef VIMAGE
206 VNET_PCPUSTAT_SYSUNINIT(ipsec6stat);
207 #endif /* VIMAGE */
208
209 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE;
210 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE;
211 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE;
212 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE;
213 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */
214
215 SYSCTL_DECL(_net_inet6_ipsec6);
216
217 /* net.inet6.ipsec6 */
218 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy,
219 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(def_policy).policy, 0,
220 "IPsec default policy.");
221 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
222 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0,
223 "Default ESP transport mode level.");
224 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
225 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0,
226 "Default ESP tunnel mode level.");
227 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
228 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0,
229 "AH transfer mode default level.");
230 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
231 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0,
232 "AH tunnel mode default level.");
233 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ECN, ecn,
234 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0,
235 "Explicit Congestion Notification handling.");
236 SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug,
237 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0,
238 "Enable IPsec debugging output when set.");
239 SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats,
240 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics.");
241 #endif /* INET6 */
242
243 static int ipsec_in_reject(struct secpolicy *, struct mbuf *);
244 static int ipsec_setspidx_inpcb(struct mbuf *, struct inpcb *);
245 static int ipsec_setspidx(struct mbuf *, struct secpolicyindex *, int);
246 static void ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *, int);
247 static int ipsec4_setspidx_ipaddr(struct mbuf *, struct secpolicyindex *);
248 #ifdef INET6
249 static void ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *, int);
250 static int ipsec6_setspidx_ipaddr(struct mbuf *, struct secpolicyindex *);
251 #endif
252 static void ipsec_delpcbpolicy(struct inpcbpolicy *);
253 static struct secpolicy *ipsec_deepcopy_policy(struct secpolicy *src);
254 static void vshiftl(unsigned char *, int, int);
255
256 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy");
257
258 /*
259 * Return a held reference to the default SP.
260 */
261 static struct secpolicy *
key_allocsp_default(const char * where,int tag)262 key_allocsp_default(const char* where, int tag)
263 {
264 struct secpolicy *sp;
265
266 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
267 printf("DP key_allocsp_default from %s:%u\n", where, tag));
268
269 sp = &V_def_policy;
270 if (sp->policy != IPSEC_POLICY_DISCARD &&
271 sp->policy != IPSEC_POLICY_NONE) {
272 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n",
273 sp->policy, IPSEC_POLICY_NONE));
274 sp->policy = IPSEC_POLICY_NONE;
275 }
276 key_addref(sp);
277
278 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
279 printf("DP key_allocsp_default returns SP:%p (%u)\n",
280 sp, sp->refcnt));
281 return (sp);
282 }
283 #define KEY_ALLOCSP_DEFAULT() \
284 key_allocsp_default(__FILE__, __LINE__)
285
286 /*
287 * For OUTBOUND packet having a socket. Searching SPD for packet,
288 * and return a pointer to SP.
289 * OUT: NULL: no apropreate SP found, the following value is set to error.
290 * 0 : bypass
291 * EACCES : discard packet.
292 * ENOENT : ipsec_acquire() in progress, maybe.
293 * others : error occured.
294 * others: a pointer to SP
295 *
296 * NOTE: IPv6 mapped adddress concern is implemented here.
297 */
298 struct secpolicy *
ipsec_getpolicy(struct tdb_ident * tdbi,u_int dir)299 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir)
300 {
301 struct secpolicy *sp;
302
303 IPSEC_ASSERT(tdbi != NULL, ("null tdbi"));
304 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
305 ("invalid direction %u", dir));
306
307 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir);
308 if (sp == NULL) /*XXX????*/
309 sp = KEY_ALLOCSP_DEFAULT();
310 IPSEC_ASSERT(sp != NULL, ("null SP"));
311 return (sp);
312 }
313
314 /*
315 * For OUTBOUND packet having a socket. Searching SPD for packet,
316 * and return a pointer to SP.
317 * OUT: NULL: no apropreate SP found, the following value is set to error.
318 * 0 : bypass
319 * EACCES : discard packet.
320 * ENOENT : ipsec_acquire() in progress, maybe.
321 * others : error occured.
322 * others: a pointer to SP
323 *
324 * NOTE: IPv6 mapped adddress concern is implemented here.
325 */
326 static struct secpolicy *
ipsec_getpolicybysock(struct mbuf * m,u_int dir,struct inpcb * inp,int * error)327 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error)
328 {
329 struct inpcbpolicy *pcbsp;
330 struct secpolicy *currsp = NULL; /* Policy on socket. */
331 struct secpolicy *sp;
332
333 IPSEC_ASSERT(m != NULL, ("null mbuf"));
334 IPSEC_ASSERT(inp != NULL, ("null inpcb"));
335 IPSEC_ASSERT(error != NULL, ("null error"));
336 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
337 ("invalid direction %u", dir));
338
339 if (!key_havesp(dir)) {
340 /* No SP found, use system default. */
341 sp = KEY_ALLOCSP_DEFAULT();
342 return (sp);
343 }
344
345 /* Set spidx in pcb. */
346 *error = ipsec_setspidx_inpcb(m, inp);
347 if (*error)
348 return (NULL);
349
350 pcbsp = inp->inp_sp;
351 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp"));
352 switch (dir) {
353 case IPSEC_DIR_INBOUND:
354 currsp = pcbsp->sp_in;
355 break;
356 case IPSEC_DIR_OUTBOUND:
357 currsp = pcbsp->sp_out;
358 break;
359 }
360 IPSEC_ASSERT(currsp != NULL, ("null currsp"));
361
362 if (pcbsp->priv) { /* When privilieged socket. */
363 switch (currsp->policy) {
364 case IPSEC_POLICY_BYPASS:
365 case IPSEC_POLICY_IPSEC:
366 key_addref(currsp);
367 sp = currsp;
368 break;
369
370 case IPSEC_POLICY_ENTRUST:
371 /* Look for a policy in SPD. */
372 sp = KEY_ALLOCSP(&currsp->spidx, dir);
373 if (sp == NULL) /* No SP found. */
374 sp = KEY_ALLOCSP_DEFAULT();
375 break;
376
377 default:
378 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n",
379 __func__, currsp->policy));
380 *error = EINVAL;
381 return (NULL);
382 }
383 } else { /* Unpriv, SPD has policy. */
384 sp = KEY_ALLOCSP(&currsp->spidx, dir);
385 if (sp == NULL) { /* No SP found. */
386 switch (currsp->policy) {
387 case IPSEC_POLICY_BYPASS:
388 ipseclog((LOG_ERR, "%s: Illegal policy for "
389 "non-priviliged defined %d\n",
390 __func__, currsp->policy));
391 *error = EINVAL;
392 return (NULL);
393
394 case IPSEC_POLICY_ENTRUST:
395 sp = KEY_ALLOCSP_DEFAULT();
396 break;
397
398 case IPSEC_POLICY_IPSEC:
399 key_addref(currsp);
400 sp = currsp;
401 break;
402
403 default:
404 ipseclog((LOG_ERR, "%s: Invalid policy for "
405 "PCB %d\n", __func__, currsp->policy));
406 *error = EINVAL;
407 return (NULL);
408 }
409 }
410 }
411 IPSEC_ASSERT(sp != NULL,
412 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy));
413 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
414 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n",
415 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt));
416 return (sp);
417 }
418
419 /*
420 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet,
421 * and return a pointer to SP.
422 * OUT: positive: a pointer to the entry for security policy leaf matched.
423 * NULL: no apropreate SP found, the following value is set to error.
424 * 0 : bypass
425 * EACCES : discard packet.
426 * ENOENT : ipsec_acquire() in progress, maybe.
427 * others : error occured.
428 */
429 struct secpolicy *
ipsec_getpolicybyaddr(struct mbuf * m,u_int dir,int * error)430 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int *error)
431 {
432 struct secpolicyindex spidx;
433 struct secpolicy *sp;
434
435 IPSEC_ASSERT(m != NULL, ("null mbuf"));
436 IPSEC_ASSERT(error != NULL, ("null error"));
437 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
438 ("invalid direction %u", dir));
439
440 sp = NULL;
441 *error = 0;
442 if (key_havesp(dir)) {
443 /* Make an index to look for a policy. */
444 *error = ipsec_setspidx(m, &spidx, 0);
445 if (*error != 0) {
446 DPRINTF(("%s: setpidx failed, dir %u\n",
447 __func__, dir));
448 return (NULL);
449 }
450 spidx.dir = dir;
451 sp = KEY_ALLOCSP(&spidx, dir);
452 }
453 if (sp == NULL) /* No SP found, use system default. */
454 sp = KEY_ALLOCSP_DEFAULT();
455 IPSEC_ASSERT(sp != NULL, ("null SP"));
456 return (sp);
457 }
458
459 struct secpolicy *
ipsec4_checkpolicy(struct mbuf * m,u_int dir,int * error,struct inpcb * inp)460 ipsec4_checkpolicy(struct mbuf *m, u_int dir, int *error, struct inpcb *inp)
461 {
462 struct secpolicy *sp;
463
464 *error = 0;
465 if (inp == NULL)
466 sp = ipsec_getpolicybyaddr(m, dir, error);
467 else
468 sp = ipsec_getpolicybysock(m, dir, inp, error);
469 if (sp == NULL) {
470 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error"));
471 IPSECSTAT_INC(ips_out_inval);
472 return (NULL);
473 }
474 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error));
475 switch (sp->policy) {
476 case IPSEC_POLICY_ENTRUST:
477 default:
478 printf("%s: invalid policy %u\n", __func__, sp->policy);
479 /* FALLTHROUGH */
480 case IPSEC_POLICY_DISCARD:
481 IPSECSTAT_INC(ips_out_polvio);
482 *error = -EINVAL; /* Packet is discarded by caller. */
483 break;
484 case IPSEC_POLICY_BYPASS:
485 case IPSEC_POLICY_NONE:
486 KEY_FREESP(&sp);
487 sp = NULL; /* NB: force NULL result. */
488 break;
489 case IPSEC_POLICY_IPSEC:
490 if (sp->req == NULL) /* Acquire a SA. */
491 *error = key_spdacquire(sp);
492 break;
493 }
494 if (*error != 0) {
495 KEY_FREESP(&sp);
496 sp = NULL;
497 }
498 return (sp);
499 }
500
501 static int
ipsec_setspidx_inpcb(struct mbuf * m,struct inpcb * inp)502 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp)
503 {
504 int error;
505
506 IPSEC_ASSERT(inp != NULL, ("null inp"));
507 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
508 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL,
509 ("null sp_in || sp_out"));
510
511 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1);
512 if (error == 0) {
513 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND;
514 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx;
515 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND;
516 } else {
517 bzero(&inp->inp_sp->sp_in->spidx,
518 sizeof (inp->inp_sp->sp_in->spidx));
519 bzero(&inp->inp_sp->sp_out->spidx,
520 sizeof (inp->inp_sp->sp_in->spidx));
521 }
522 return (error);
523 }
524
525 /*
526 * Configure security policy index (src/dst/proto/sport/dport)
527 * by looking at the content of mbuf.
528 * The caller is responsible for error recovery (like clearing up spidx).
529 */
530 static int
ipsec_setspidx(struct mbuf * m,struct secpolicyindex * spidx,int needport)531 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport)
532 {
533 struct ip *ip = NULL;
534 struct ip ipbuf;
535 u_int v;
536 struct mbuf *n;
537 int len;
538 int error;
539
540 IPSEC_ASSERT(m != NULL, ("null mbuf"));
541
542 /*
543 * Validate m->m_pkthdr.len. We see incorrect length if we
544 * mistakenly call this function with inconsistent mbuf chain
545 * (like 4.4BSD tcp/udp processing). XXX Should we panic here?
546 */
547 len = 0;
548 for (n = m; n; n = n->m_next)
549 len += n->m_len;
550 if (m->m_pkthdr.len != len) {
551 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
552 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n",
553 __func__, len, m->m_pkthdr.len));
554 return (EINVAL);
555 }
556
557 if (m->m_pkthdr.len < sizeof(struct ip)) {
558 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
559 printf("%s: pkthdr len(%d) too small (v4), ignored.\n",
560 __func__, m->m_pkthdr.len));
561 return (EINVAL);
562 }
563
564 if (m->m_len >= sizeof(*ip))
565 ip = mtod(m, struct ip *);
566 else {
567 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf);
568 ip = &ipbuf;
569 }
570 v = ip->ip_v;
571 switch (v) {
572 case 4:
573 error = ipsec4_setspidx_ipaddr(m, spidx);
574 if (error)
575 return (error);
576 ipsec4_get_ulp(m, spidx, needport);
577 return (0);
578 #ifdef INET6
579 case 6:
580 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) {
581 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
582 printf("%s: pkthdr len(%d) too small (v6), "
583 "ignored\n", __func__, m->m_pkthdr.len));
584 return (EINVAL);
585 }
586 error = ipsec6_setspidx_ipaddr(m, spidx);
587 if (error)
588 return (error);
589 ipsec6_get_ulp(m, spidx, needport);
590 return (0);
591 #endif
592 default:
593 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
594 printf("%s: " "unknown IP version %u, ignored.\n",
595 __func__, v));
596 return (EINVAL);
597 }
598 }
599
600 static void
ipsec4_get_ulp(struct mbuf * m,struct secpolicyindex * spidx,int needport)601 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
602 {
603 u_int8_t nxt;
604 int off;
605
606 /* Sanity check. */
607 IPSEC_ASSERT(m != NULL, ("null mbuf"));
608 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short"));
609
610 if (m->m_len >= sizeof (struct ip)) {
611 struct ip *ip = mtod(m, struct ip *);
612 if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
613 goto done;
614 off = ip->ip_hl << 2;
615 nxt = ip->ip_p;
616 } else {
617 struct ip ih;
618
619 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih);
620 if (ih.ip_off & htons(IP_MF | IP_OFFMASK))
621 goto done;
622 off = ih.ip_hl << 2;
623 nxt = ih.ip_p;
624 }
625
626 while (off < m->m_pkthdr.len) {
627 struct ip6_ext ip6e;
628 struct tcphdr th;
629 struct udphdr uh;
630
631 switch (nxt) {
632 case IPPROTO_TCP:
633 spidx->ul_proto = nxt;
634 if (!needport)
635 goto done_proto;
636 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
637 goto done;
638 m_copydata(m, off, sizeof (th), (caddr_t) &th);
639 spidx->src.sin.sin_port = th.th_sport;
640 spidx->dst.sin.sin_port = th.th_dport;
641 return;
642 case IPPROTO_UDP:
643 spidx->ul_proto = nxt;
644 if (!needport)
645 goto done_proto;
646 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
647 goto done;
648 m_copydata(m, off, sizeof (uh), (caddr_t) &uh);
649 spidx->src.sin.sin_port = uh.uh_sport;
650 spidx->dst.sin.sin_port = uh.uh_dport;
651 return;
652 case IPPROTO_AH:
653 if (off + sizeof(ip6e) > m->m_pkthdr.len)
654 goto done;
655 /* XXX Sigh, this works but is totally bogus. */
656 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e);
657 off += (ip6e.ip6e_len + 2) << 2;
658 nxt = ip6e.ip6e_nxt;
659 break;
660 case IPPROTO_ICMP:
661 default:
662 /* XXX Intermediate headers??? */
663 spidx->ul_proto = nxt;
664 goto done_proto;
665 }
666 }
667 done:
668 spidx->ul_proto = IPSEC_ULPROTO_ANY;
669 done_proto:
670 spidx->src.sin.sin_port = IPSEC_PORT_ANY;
671 spidx->dst.sin.sin_port = IPSEC_PORT_ANY;
672 }
673
674 /* Assumes that m is sane. */
675 static int
ipsec4_setspidx_ipaddr(struct mbuf * m,struct secpolicyindex * spidx)676 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
677 {
678 static const struct sockaddr_in template = {
679 sizeof (struct sockaddr_in),
680 AF_INET,
681 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 }
682 };
683
684 spidx->src.sin = template;
685 spidx->dst.sin = template;
686
687 if (m->m_len < sizeof (struct ip)) {
688 m_copydata(m, offsetof(struct ip, ip_src),
689 sizeof (struct in_addr),
690 (caddr_t) &spidx->src.sin.sin_addr);
691 m_copydata(m, offsetof(struct ip, ip_dst),
692 sizeof (struct in_addr),
693 (caddr_t) &spidx->dst.sin.sin_addr);
694 } else {
695 struct ip *ip = mtod(m, struct ip *);
696 spidx->src.sin.sin_addr = ip->ip_src;
697 spidx->dst.sin.sin_addr = ip->ip_dst;
698 }
699
700 spidx->prefs = sizeof(struct in_addr) << 3;
701 spidx->prefd = sizeof(struct in_addr) << 3;
702
703 return (0);
704 }
705
706 #ifdef INET6
707 static void
ipsec6_get_ulp(struct mbuf * m,struct secpolicyindex * spidx,int needport)708 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
709 {
710 int off, nxt;
711 struct tcphdr th;
712 struct udphdr uh;
713 struct icmp6_hdr ih;
714
715 /* Sanity check. */
716 if (m == NULL)
717 panic("%s: NULL pointer was passed.\n", __func__);
718
719 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
720 printf("%s:\n", __func__); kdebug_mbuf(m));
721
722 /* Set default. */
723 spidx->ul_proto = IPSEC_ULPROTO_ANY;
724 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY;
725 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY;
726
727 nxt = -1;
728 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
729 if (off < 0 || m->m_pkthdr.len < off)
730 return;
731
732 switch (nxt) {
733 case IPPROTO_TCP:
734 spidx->ul_proto = nxt;
735 if (!needport)
736 break;
737 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
738 break;
739 m_copydata(m, off, sizeof(th), (caddr_t)&th);
740 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport;
741 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport;
742 break;
743 case IPPROTO_UDP:
744 spidx->ul_proto = nxt;
745 if (!needport)
746 break;
747 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
748 break;
749 m_copydata(m, off, sizeof(uh), (caddr_t)&uh);
750 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport;
751 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport;
752 break;
753 case IPPROTO_ICMPV6:
754 spidx->ul_proto = nxt;
755 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len)
756 break;
757 m_copydata(m, off, sizeof(ih), (caddr_t)&ih);
758 ((struct sockaddr_in6 *)&spidx->src)->sin6_port =
759 htons((uint16_t)ih.icmp6_type);
760 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port =
761 htons((uint16_t)ih.icmp6_code);
762 break;
763 default:
764 /* XXX Intermediate headers??? */
765 spidx->ul_proto = nxt;
766 break;
767 }
768 }
769
770 /* Assumes that m is sane. */
771 static int
ipsec6_setspidx_ipaddr(struct mbuf * m,struct secpolicyindex * spidx)772 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
773 {
774 struct ip6_hdr *ip6 = NULL;
775 struct ip6_hdr ip6buf;
776 struct sockaddr_in6 *sin6;
777
778 if (m->m_len >= sizeof(*ip6))
779 ip6 = mtod(m, struct ip6_hdr *);
780 else {
781 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf);
782 ip6 = &ip6buf;
783 }
784
785 sin6 = (struct sockaddr_in6 *)&spidx->src;
786 bzero(sin6, sizeof(*sin6));
787 sin6->sin6_family = AF_INET6;
788 sin6->sin6_len = sizeof(struct sockaddr_in6);
789 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src));
790 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
791 sin6->sin6_addr.s6_addr16[1] = 0;
792 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]);
793 }
794 spidx->prefs = sizeof(struct in6_addr) << 3;
795
796 sin6 = (struct sockaddr_in6 *)&spidx->dst;
797 bzero(sin6, sizeof(*sin6));
798 sin6->sin6_family = AF_INET6;
799 sin6->sin6_len = sizeof(struct sockaddr_in6);
800 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst));
801 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
802 sin6->sin6_addr.s6_addr16[1] = 0;
803 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
804 }
805 spidx->prefd = sizeof(struct in6_addr) << 3;
806
807 return (0);
808 }
809 #endif
810
811 int
ipsec_run_hhooks(struct ipsec_ctx_data * ctx,int type)812 ipsec_run_hhooks(struct ipsec_ctx_data *ctx, int type)
813 {
814 int idx;
815
816 switch (ctx->af) {
817 #ifdef INET
818 case AF_INET:
819 idx = HHOOK_IPSEC_INET;
820 break;
821 #endif
822 #ifdef INET6
823 case AF_INET6:
824 idx = HHOOK_IPSEC_INET6;
825 break;
826 #endif
827 default:
828 return (EPFNOSUPPORT);
829 }
830 if (type == HHOOK_TYPE_IPSEC_IN)
831 HHOOKS_RUN_IF(V_ipsec_hhh_in[idx], ctx, NULL);
832 else
833 HHOOKS_RUN_IF(V_ipsec_hhh_out[idx], ctx, NULL);
834 if (*ctx->mp == NULL)
835 return (EACCES);
836 return (0);
837 }
838
839 static void
ipsec_delpcbpolicy(struct inpcbpolicy * p)840 ipsec_delpcbpolicy(struct inpcbpolicy *p)
841 {
842
843 free(p, M_IPSEC_INPCB);
844 }
845
846 /* Initialize policy in PCB. */
847 int
ipsec_init_policy(struct socket * so,struct inpcbpolicy ** pcb_sp)848 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp)
849 {
850 struct inpcbpolicy *new;
851
852 /* Sanity check. */
853 if (so == NULL || pcb_sp == NULL)
854 panic("%s: NULL pointer was passed.\n", __func__);
855
856 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy),
857 M_IPSEC_INPCB, M_NOWAIT|M_ZERO);
858 if (new == NULL) {
859 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
860 return (ENOBUFS);
861 }
862
863 new->priv = IPSEC_IS_PRIVILEGED_SO(so);
864
865 if ((new->sp_in = KEY_NEWSP()) == NULL) {
866 ipsec_delpcbpolicy(new);
867 return (ENOBUFS);
868 }
869 new->sp_in->policy = IPSEC_POLICY_ENTRUST;
870 if ((new->sp_out = KEY_NEWSP()) == NULL) {
871 KEY_FREESP(&new->sp_in);
872 ipsec_delpcbpolicy(new);
873 return (ENOBUFS);
874 }
875 new->sp_out->policy = IPSEC_POLICY_ENTRUST;
876 *pcb_sp = new;
877
878 return (0);
879 }
880
881 /* Copy old IPsec policy into new. */
882 int
ipsec_copy_policy(struct inpcbpolicy * old,struct inpcbpolicy * new)883 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new)
884 {
885 struct secpolicy *sp;
886
887 sp = ipsec_deepcopy_policy(old->sp_in);
888 if (sp) {
889 KEY_FREESP(&new->sp_in);
890 new->sp_in = sp;
891 } else
892 return (ENOBUFS);
893
894 sp = ipsec_deepcopy_policy(old->sp_out);
895 if (sp) {
896 KEY_FREESP(&new->sp_out);
897 new->sp_out = sp;
898 } else
899 return (ENOBUFS);
900
901 new->priv = old->priv;
902
903 return (0);
904 }
905
906 struct ipsecrequest *
ipsec_newisr(void)907 ipsec_newisr(void)
908 {
909 struct ipsecrequest *p;
910
911 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO);
912 if (p != NULL)
913 IPSECREQUEST_LOCK_INIT(p);
914 return (p);
915 }
916
917 void
ipsec_delisr(struct ipsecrequest * p)918 ipsec_delisr(struct ipsecrequest *p)
919 {
920
921 IPSECREQUEST_LOCK_DESTROY(p);
922 free(p, M_IPSEC_SR);
923 }
924
925 /* Deep-copy a policy in PCB. */
926 static struct secpolicy *
ipsec_deepcopy_policy(struct secpolicy * src)927 ipsec_deepcopy_policy(struct secpolicy *src)
928 {
929 struct ipsecrequest *newchain = NULL;
930 struct ipsecrequest *p;
931 struct ipsecrequest **q;
932 struct ipsecrequest *r;
933 struct secpolicy *dst;
934
935 if (src == NULL)
936 return (NULL);
937 dst = KEY_NEWSP();
938 if (dst == NULL)
939 return (NULL);
940
941 /*
942 * Deep-copy IPsec request chain. This is required since struct
943 * ipsecrequest is not reference counted.
944 */
945 q = &newchain;
946 for (p = src->req; p; p = p->next) {
947 *q = ipsec_newisr();
948 if (*q == NULL)
949 goto fail;
950 (*q)->saidx.proto = p->saidx.proto;
951 (*q)->saidx.mode = p->saidx.mode;
952 (*q)->level = p->level;
953 (*q)->saidx.reqid = p->saidx.reqid;
954
955 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src));
956 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst));
957
958 (*q)->sp = dst;
959
960 q = &((*q)->next);
961 }
962
963 dst->req = newchain;
964 dst->policy = src->policy;
965 /* Do not touch the refcnt fields. */
966
967 return (dst);
968
969 fail:
970 for (p = newchain; p; p = r) {
971 r = p->next;
972 ipsec_delisr(p);
973 p = NULL;
974 }
975 return (NULL);
976 }
977
978 /* Set policy and IPsec request if present. */
979 static int
ipsec_set_policy_internal(struct secpolicy ** pcb_sp,int optname,caddr_t request,size_t len,struct ucred * cred)980 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname,
981 caddr_t request, size_t len, struct ucred *cred)
982 {
983 struct sadb_x_policy *xpl;
984 struct secpolicy *newsp = NULL;
985 int error;
986
987 /* Sanity check. */
988 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL)
989 return (EINVAL);
990 if (len < sizeof(*xpl))
991 return (EINVAL);
992 xpl = (struct sadb_x_policy *)request;
993
994 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
995 printf("%s: passed policy\n", __func__);
996 kdebug_sadb_x_policy((struct sadb_ext *)xpl));
997
998 /* Check policy type. */
999 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */
1000 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD
1001 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE)
1002 return (EINVAL);
1003
1004 /* Check privileged socket. */
1005 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) {
1006 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0);
1007 if (error)
1008 return (EACCES);
1009 }
1010
1011 /* Allocating new SP entry. */
1012 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL)
1013 return (error);
1014
1015 /* Clear old SP and set new SP. */
1016 KEY_FREESP(pcb_sp);
1017 *pcb_sp = newsp;
1018 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1019 printf("%s: new policy\n", __func__);
1020 kdebug_secpolicy(newsp));
1021
1022 return (0);
1023 }
1024
1025 int
ipsec_set_policy(struct inpcb * inp,int optname,caddr_t request,size_t len,struct ucred * cred)1026 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request,
1027 size_t len, struct ucred *cred)
1028 {
1029 struct sadb_x_policy *xpl;
1030 struct secpolicy **pcb_sp;
1031
1032 /* Sanity check. */
1033 if (inp == NULL || request == NULL)
1034 return (EINVAL);
1035 if (len < sizeof(*xpl))
1036 return (EINVAL);
1037 xpl = (struct sadb_x_policy *)request;
1038
1039 /* Select direction. */
1040 switch (xpl->sadb_x_policy_dir) {
1041 case IPSEC_DIR_INBOUND:
1042 pcb_sp = &inp->inp_sp->sp_in;
1043 break;
1044 case IPSEC_DIR_OUTBOUND:
1045 pcb_sp = &inp->inp_sp->sp_out;
1046 break;
1047 default:
1048 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1049 xpl->sadb_x_policy_dir));
1050 return (EINVAL);
1051 }
1052
1053 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred));
1054 }
1055
1056 int
ipsec_get_policy(struct inpcb * inp,caddr_t request,size_t len,struct mbuf ** mp)1057 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len,
1058 struct mbuf **mp)
1059 {
1060 struct sadb_x_policy *xpl;
1061 struct secpolicy *pcb_sp;
1062
1063 /* Sanity check. */
1064 if (inp == NULL || request == NULL || mp == NULL)
1065 return (EINVAL);
1066 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
1067 if (len < sizeof(*xpl))
1068 return (EINVAL);
1069 xpl = (struct sadb_x_policy *)request;
1070
1071 /* Select direction. */
1072 switch (xpl->sadb_x_policy_dir) {
1073 case IPSEC_DIR_INBOUND:
1074 pcb_sp = inp->inp_sp->sp_in;
1075 break;
1076 case IPSEC_DIR_OUTBOUND:
1077 pcb_sp = inp->inp_sp->sp_out;
1078 break;
1079 default:
1080 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1081 xpl->sadb_x_policy_dir));
1082 return (EINVAL);
1083 }
1084
1085 /* Sanity check. Should be an IPSEC_ASSERT. */
1086 if (pcb_sp == NULL)
1087 return (EINVAL);
1088
1089 *mp = key_sp2msg(pcb_sp);
1090 if (!*mp) {
1091 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
1092 return (ENOBUFS);
1093 }
1094
1095 (*mp)->m_type = MT_DATA;
1096 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1097 printf("%s:\n", __func__); kdebug_mbuf(*mp));
1098
1099 return (0);
1100 }
1101
1102 /* Delete policy in PCB. */
1103 int
ipsec_delete_pcbpolicy(struct inpcb * inp)1104 ipsec_delete_pcbpolicy(struct inpcb *inp)
1105 {
1106 IPSEC_ASSERT(inp != NULL, ("null inp"));
1107
1108 if (inp->inp_sp == NULL)
1109 return (0);
1110
1111 if (inp->inp_sp->sp_in != NULL)
1112 KEY_FREESP(&inp->inp_sp->sp_in);
1113
1114 if (inp->inp_sp->sp_out != NULL)
1115 KEY_FREESP(&inp->inp_sp->sp_out);
1116
1117 ipsec_delpcbpolicy(inp->inp_sp);
1118 inp->inp_sp = NULL;
1119
1120 return (0);
1121 }
1122
1123 /*
1124 * Return current level.
1125 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned.
1126 */
1127 u_int
ipsec_get_reqlevel(struct ipsecrequest * isr)1128 ipsec_get_reqlevel(struct ipsecrequest *isr)
1129 {
1130 u_int level = 0;
1131 u_int esp_trans_deflev, esp_net_deflev;
1132 u_int ah_trans_deflev, ah_net_deflev;
1133
1134 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument"));
1135 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family,
1136 ("af family mismatch, src %u, dst %u",
1137 isr->sp->spidx.src.sa.sa_family,
1138 isr->sp->spidx.dst.sa.sa_family));
1139
1140 /* XXX Note that we have ipseclog() expanded here - code sync issue. */
1141 #define IPSEC_CHECK_DEFAULT(lev) \
1142 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \
1143 && (lev) != IPSEC_LEVEL_UNIQUE) \
1144 ? (V_ipsec_debug \
1145 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\
1146 (lev), IPSEC_LEVEL_REQUIRE) \
1147 : 0), \
1148 (lev) = IPSEC_LEVEL_REQUIRE, \
1149 (lev) \
1150 : (lev))
1151
1152 /* Set default level. */
1153 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) {
1154 #ifdef INET
1155 case AF_INET:
1156 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev);
1157 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev);
1158 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev);
1159 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev);
1160 break;
1161 #endif
1162 #ifdef INET6
1163 case AF_INET6:
1164 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev);
1165 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev);
1166 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev);
1167 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev);
1168 break;
1169 #endif /* INET6 */
1170 default:
1171 panic("%s: unknown af %u",
1172 __func__, isr->sp->spidx.src.sa.sa_family);
1173 }
1174
1175 #undef IPSEC_CHECK_DEFAULT
1176
1177 /* Set level. */
1178 switch (isr->level) {
1179 case IPSEC_LEVEL_DEFAULT:
1180 switch (isr->saidx.proto) {
1181 case IPPROTO_ESP:
1182 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1183 level = esp_net_deflev;
1184 else
1185 level = esp_trans_deflev;
1186 break;
1187 case IPPROTO_AH:
1188 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1189 level = ah_net_deflev;
1190 else
1191 level = ah_trans_deflev;
1192 break;
1193 case IPPROTO_IPCOMP:
1194 /*
1195 * We don't really care, as IPcomp document says that
1196 * we shouldn't compress small packets.
1197 */
1198 level = IPSEC_LEVEL_USE;
1199 break;
1200 default:
1201 panic("%s: Illegal protocol defined %u\n", __func__,
1202 isr->saidx.proto);
1203 }
1204 break;
1205
1206 case IPSEC_LEVEL_USE:
1207 case IPSEC_LEVEL_REQUIRE:
1208 level = isr->level;
1209 break;
1210 case IPSEC_LEVEL_UNIQUE:
1211 level = IPSEC_LEVEL_REQUIRE;
1212 break;
1213
1214 default:
1215 panic("%s: Illegal IPsec level %u\n", __func__, isr->level);
1216 }
1217
1218 return (level);
1219 }
1220
1221 /*
1222 * Check security policy requirements against the actual
1223 * packet contents. Return one if the packet should be
1224 * reject as "invalid"; otherwiser return zero to have the
1225 * packet treated as "valid".
1226 *
1227 * OUT:
1228 * 0: valid
1229 * 1: invalid
1230 */
1231 static int
ipsec_in_reject(struct secpolicy * sp,struct mbuf * m)1232 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m)
1233 {
1234 struct ipsecrequest *isr;
1235 int need_auth;
1236
1237 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1238 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1239
1240 /* Check policy. */
1241 switch (sp->policy) {
1242 case IPSEC_POLICY_DISCARD:
1243 return (1);
1244 case IPSEC_POLICY_BYPASS:
1245 case IPSEC_POLICY_NONE:
1246 return (0);
1247 }
1248
1249 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1250 ("invalid policy %u", sp->policy));
1251
1252 /* XXX Should compare policy against IPsec header history. */
1253
1254 need_auth = 0;
1255 for (isr = sp->req; isr != NULL; isr = isr->next) {
1256 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE)
1257 continue;
1258 switch (isr->saidx.proto) {
1259 case IPPROTO_ESP:
1260 if ((m->m_flags & M_DECRYPTED) == 0) {
1261 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1262 printf("%s: ESP m_flags:%x\n", __func__,
1263 m->m_flags));
1264 return (1);
1265 }
1266
1267 if (!need_auth &&
1268 isr->sav != NULL &&
1269 isr->sav->tdb_authalgxform != NULL &&
1270 (m->m_flags & M_AUTHIPDGM) == 0) {
1271 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1272 printf("%s: ESP/AH m_flags:%x\n", __func__,
1273 m->m_flags));
1274 return (1);
1275 }
1276 break;
1277 case IPPROTO_AH:
1278 need_auth = 1;
1279 if ((m->m_flags & M_AUTHIPHDR) == 0) {
1280 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1281 printf("%s: AH m_flags:%x\n", __func__,
1282 m->m_flags));
1283 return (1);
1284 }
1285 break;
1286 case IPPROTO_IPCOMP:
1287 /*
1288 * We don't really care, as IPcomp document
1289 * says that we shouldn't compress small
1290 * packets. IPComp policy should always be
1291 * treated as being in "use" level.
1292 */
1293 break;
1294 }
1295 }
1296 return (0); /* Valid. */
1297 }
1298
1299 /*
1300 * Non zero return value means security policy DISCARD or policy violation.
1301 */
1302 static int
ipsec46_in_reject(struct mbuf * m,struct inpcb * inp)1303 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp)
1304 {
1305 struct secpolicy *sp;
1306 int error;
1307 int result;
1308
1309 if (!key_havesp(IPSEC_DIR_INBOUND))
1310 return 0;
1311
1312 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1313
1314 /* Get SP for this packet. */
1315 if (inp == NULL)
1316 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, &error);
1317 else
1318 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error);
1319
1320 if (sp != NULL) {
1321 result = ipsec_in_reject(sp, m);
1322 KEY_FREESP(&sp);
1323 } else {
1324 result = 1; /* treat errors as policy violation */
1325 }
1326 return (result);
1327 }
1328
1329 /*
1330 * Check AH/ESP integrity.
1331 * This function is called from tcp_input(), udp_input(),
1332 * and {ah,esp}4_input for tunnel mode.
1333 */
1334 int
ipsec4_in_reject(struct mbuf * m,struct inpcb * inp)1335 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp)
1336 {
1337 int result;
1338
1339 result = ipsec46_in_reject(m, inp);
1340 if (result)
1341 IPSECSTAT_INC(ips_in_polvio);
1342
1343 return (result);
1344 }
1345
1346 #ifdef INET6
1347 /*
1348 * Check AH/ESP integrity.
1349 * This function is called from tcp6_input(), udp6_input(),
1350 * and {ah,esp}6_input for tunnel mode.
1351 */
1352 int
ipsec6_in_reject(struct mbuf * m,struct inpcb * inp)1353 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp)
1354 {
1355 int result;
1356
1357 result = ipsec46_in_reject(m, inp);
1358 if (result)
1359 IPSEC6STAT_INC(ips_in_polvio);
1360
1361 return (result);
1362 }
1363 #endif
1364
1365 /*
1366 * Compute the byte size to be occupied by IPsec header.
1367 * In case it is tunnelled, it includes the size of outer IP header.
1368 * NOTE: SP passed is freed in this function.
1369 */
1370 static size_t
ipsec_hdrsiz_internal(struct secpolicy * sp)1371 ipsec_hdrsiz_internal(struct secpolicy *sp)
1372 {
1373 struct ipsecrequest *isr;
1374 size_t size;
1375
1376 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1377 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1378
1379 switch (sp->policy) {
1380 case IPSEC_POLICY_DISCARD:
1381 case IPSEC_POLICY_BYPASS:
1382 case IPSEC_POLICY_NONE:
1383 return (0);
1384 }
1385
1386 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1387 ("invalid policy %u", sp->policy));
1388
1389 size = 0;
1390 for (isr = sp->req; isr != NULL; isr = isr->next) {
1391 size_t clen = 0;
1392
1393 switch (isr->saidx.proto) {
1394 case IPPROTO_ESP:
1395 clen = esp_hdrsiz(isr->sav);
1396 break;
1397 case IPPROTO_AH:
1398 clen = ah_hdrsiz(isr->sav);
1399 break;
1400 case IPPROTO_IPCOMP:
1401 clen = sizeof(struct ipcomp);
1402 break;
1403 }
1404
1405 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
1406 switch (isr->saidx.dst.sa.sa_family) {
1407 case AF_INET:
1408 clen += sizeof(struct ip);
1409 break;
1410 #ifdef INET6
1411 case AF_INET6:
1412 clen += sizeof(struct ip6_hdr);
1413 break;
1414 #endif
1415 default:
1416 ipseclog((LOG_ERR, "%s: unknown AF %d in "
1417 "IPsec tunnel SA\n", __func__,
1418 ((struct sockaddr *)&isr->saidx.dst)->sa_family));
1419 break;
1420 }
1421 }
1422 size += clen;
1423 }
1424
1425 return (size);
1426 }
1427
1428 /*
1429 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(),
1430 * disabled ip6_ipsec_mtu() and ip6_forward().
1431 */
1432 size_t
ipsec_hdrsiz(struct mbuf * m,u_int dir,struct inpcb * inp)1433 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp)
1434 {
1435 struct secpolicy *sp;
1436 int error;
1437 size_t size;
1438
1439 if (!key_havesp(dir))
1440 return 0;
1441
1442 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1443
1444 /* Get SP for this packet. */
1445 if (inp == NULL)
1446 sp = ipsec_getpolicybyaddr(m, dir, &error);
1447 else
1448 sp = ipsec_getpolicybysock(m, dir, inp, &error);
1449
1450 if (sp != NULL) {
1451 size = ipsec_hdrsiz_internal(sp);
1452 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1453 printf("%s: size:%lu.\n", __func__,
1454 (unsigned long)size));
1455
1456 KEY_FREESP(&sp);
1457 } else {
1458 size = 0; /* XXX Should be panic?
1459 * -> No, we are called w/o knowing if
1460 * IPsec processing is needed. */
1461 }
1462 return (size);
1463 }
1464
1465 /*
1466 * Check the variable replay window.
1467 * ipsec_chkreplay() performs replay check before ICV verification.
1468 * ipsec_updatereplay() updates replay bitmap. This must be called after
1469 * ICV verification (it also performs replay check, which is usually done
1470 * beforehand).
1471 * 0 (zero) is returned if packet disallowed, 1 if packet permitted.
1472 *
1473 * Based on RFC 2401.
1474 */
1475 int
ipsec_chkreplay(u_int32_t seq,struct secasvar * sav)1476 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav)
1477 {
1478 const struct secreplay *replay;
1479 u_int32_t diff;
1480 int fr;
1481 u_int32_t wsizeb; /* Constant: bits of window size. */
1482 int frlast; /* Constant: last frame. */
1483
1484 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1485 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1486
1487 replay = sav->replay;
1488
1489 if (replay->wsize == 0)
1490 return (1); /* No need to check replay. */
1491
1492 /* Constant. */
1493 frlast = replay->wsize - 1;
1494 wsizeb = replay->wsize << 3;
1495
1496 /* Sequence number of 0 is invalid. */
1497 if (seq == 0)
1498 return (0);
1499
1500 /* First time is always okay. */
1501 if (replay->count == 0)
1502 return (1);
1503
1504 if (seq > replay->lastseq) {
1505 /* Larger sequences are okay. */
1506 return (1);
1507 } else {
1508 /* seq is equal or less than lastseq. */
1509 diff = replay->lastseq - seq;
1510
1511 /* Over range to check, i.e. too old or wrapped. */
1512 if (diff >= wsizeb)
1513 return (0);
1514
1515 fr = frlast - diff / 8;
1516
1517 /* This packet already seen? */
1518 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1519 return (0);
1520
1521 /* Out of order but good. */
1522 return (1);
1523 }
1524 }
1525
1526 /*
1527 * Check replay counter whether to update or not.
1528 * OUT: 0: OK
1529 * 1: NG
1530 */
1531 int
ipsec_updatereplay(u_int32_t seq,struct secasvar * sav)1532 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav)
1533 {
1534 char buf[128];
1535 struct secreplay *replay;
1536 u_int32_t diff;
1537 int fr;
1538 u_int32_t wsizeb; /* Constant: bits of window size. */
1539 int frlast; /* Constant: last frame. */
1540
1541 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1542 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1543
1544 replay = sav->replay;
1545
1546 if (replay->wsize == 0)
1547 goto ok; /* No need to check replay. */
1548
1549 /* Constant. */
1550 frlast = replay->wsize - 1;
1551 wsizeb = replay->wsize << 3;
1552
1553 /* Sequence number of 0 is invalid. */
1554 if (seq == 0)
1555 return (1);
1556
1557 /* First time. */
1558 if (replay->count == 0) {
1559 replay->lastseq = seq;
1560 bzero(replay->bitmap, replay->wsize);
1561 (replay->bitmap)[frlast] = 1;
1562 goto ok;
1563 }
1564
1565 if (seq > replay->lastseq) {
1566 /* seq is larger than lastseq. */
1567 diff = seq - replay->lastseq;
1568
1569 /* New larger sequence number. */
1570 if (diff < wsizeb) {
1571 /* In window. */
1572 /* Set bit for this packet. */
1573 vshiftl(replay->bitmap, diff, replay->wsize);
1574 (replay->bitmap)[frlast] |= 1;
1575 } else {
1576 /* This packet has a "way larger". */
1577 bzero(replay->bitmap, replay->wsize);
1578 (replay->bitmap)[frlast] = 1;
1579 }
1580 replay->lastseq = seq;
1581
1582 /* Larger is good. */
1583 } else {
1584 /* seq is equal or less than lastseq. */
1585 diff = replay->lastseq - seq;
1586
1587 /* Over range to check, i.e. too old or wrapped. */
1588 if (diff >= wsizeb)
1589 return (1);
1590
1591 fr = frlast - diff / 8;
1592
1593 /* This packet already seen? */
1594 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1595 return (1);
1596
1597 /* Mark as seen. */
1598 (replay->bitmap)[fr] |= (1 << (diff % 8));
1599
1600 /* Out of order but good. */
1601 }
1602
1603 ok:
1604 if (replay->count == ~0) {
1605
1606 /* Set overflow flag. */
1607 replay->overflow++;
1608
1609 /* Don't increment, no more packets accepted. */
1610 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0)
1611 return (1);
1612
1613 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n",
1614 __func__, replay->overflow,
1615 ipsec_logsastr(sav, buf, sizeof(buf))));
1616 }
1617
1618 replay->count++;
1619
1620 return (0);
1621 }
1622
1623 /*
1624 * Shift variable length buffer to left.
1625 * IN: bitmap: pointer to the buffer
1626 * nbit: the number of to shift.
1627 * wsize: buffer size (bytes).
1628 */
1629 static void
vshiftl(unsigned char * bitmap,int nbit,int wsize)1630 vshiftl(unsigned char *bitmap, int nbit, int wsize)
1631 {
1632 int s, j, i;
1633 unsigned char over;
1634
1635 for (j = 0; j < nbit; j += 8) {
1636 s = (nbit - j < 8) ? (nbit - j): 8;
1637 bitmap[0] <<= s;
1638 for (i = 1; i < wsize; i++) {
1639 over = (bitmap[i] >> (8 - s));
1640 bitmap[i] <<= s;
1641 bitmap[i-1] |= over;
1642 }
1643 }
1644 }
1645
1646 /* Return a printable string for the address. */
1647 char*
ipsec_address(union sockaddr_union * sa,char * buf,socklen_t size)1648 ipsec_address(union sockaddr_union* sa, char *buf, socklen_t size)
1649 {
1650
1651 switch (sa->sa.sa_family) {
1652 #ifdef INET
1653 case AF_INET:
1654 return (inet_ntop(AF_INET, &sa->sin.sin_addr, buf, size));
1655 #endif /* INET */
1656 #ifdef INET6
1657 case AF_INET6:
1658 return (inet_ntop(AF_INET6, &sa->sin6.sin6_addr, buf, size));
1659 #endif /* INET6 */
1660 default:
1661 return ("(unknown address family)");
1662 }
1663 }
1664
1665 char *
ipsec_logsastr(struct secasvar * sav,char * buf,size_t size)1666 ipsec_logsastr(struct secasvar *sav, char *buf, size_t size)
1667 {
1668 char sbuf[INET6_ADDRSTRLEN], dbuf[INET6_ADDRSTRLEN];
1669
1670 IPSEC_ASSERT(sav->sah->saidx.src.sa.sa_family ==
1671 sav->sah->saidx.dst.sa.sa_family, ("address family mismatch"));
1672
1673 snprintf(buf, size, "SA(SPI=%08lx src=%s dst=%s)",
1674 (u_long)ntohl(sav->spi),
1675 ipsec_address(&sav->sah->saidx.src, sbuf, sizeof(sbuf)),
1676 ipsec_address(&sav->sah->saidx.dst, dbuf, sizeof(dbuf)));
1677 return (buf);
1678 }
1679
1680 void
ipsec_dumpmbuf(struct mbuf * m)1681 ipsec_dumpmbuf(struct mbuf *m)
1682 {
1683 int totlen;
1684 int i;
1685 u_char *p;
1686
1687 totlen = 0;
1688 printf("---\n");
1689 while (m) {
1690 p = mtod(m, u_char *);
1691 for (i = 0; i < m->m_len; i++) {
1692 printf("%02x ", p[i]);
1693 totlen++;
1694 if (totlen % 16 == 0)
1695 printf("\n");
1696 }
1697 m = m->m_next;
1698 }
1699 if (totlen % 16 != 0)
1700 printf("\n");
1701 printf("---\n");
1702 }
1703
1704 static void
def_policy_init(const void * unused __unused)1705 def_policy_init(const void *unused __unused)
1706 {
1707
1708 bzero(&V_def_policy, sizeof(struct secpolicy));
1709 V_def_policy.policy = IPSEC_POLICY_NONE;
1710 V_def_policy.refcnt = 1;
1711 }
1712 VNET_SYSINIT(def_policy_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY,
1713 def_policy_init, NULL);
1714
1715
1716 /* XXX This stuff doesn't belong here... */
1717
1718 static struct xformsw* xforms = NULL;
1719
1720 /*
1721 * Register a transform; typically at system startup.
1722 */
1723 void
xform_register(struct xformsw * xsp)1724 xform_register(struct xformsw* xsp)
1725 {
1726
1727 xsp->xf_next = xforms;
1728 xforms = xsp;
1729 }
1730
1731 /*
1732 * Initialize transform support in an sav.
1733 */
1734 int
xform_init(struct secasvar * sav,int xftype)1735 xform_init(struct secasvar *sav, int xftype)
1736 {
1737 struct xformsw *xsp;
1738
1739 if (sav->tdb_xform != NULL) /* Previously initialized. */
1740 return (0);
1741 for (xsp = xforms; xsp; xsp = xsp->xf_next)
1742 if (xsp->xf_type == xftype)
1743 return ((*xsp->xf_init)(sav, xsp));
1744 return (EINVAL);
1745 }
1746