summaryrefslogtreecommitdiff
path: root/sys/netinet/ip_ipsp.c
blob: 5872f65c675683cac2b67b1ebc56c200e0290aef (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
/*	$OpenBSD: ip_ipsp.c,v 1.145 2002/02/23 22:16:13 angelos Exp $	*/
/*
 * The authors of this code are John Ioannidis (ji@tla.org),
 * Angelos D. Keromytis (kermit@csd.uch.gr),
 * Niels Provos (provos@physnet.uni-hamburg.de) and
 * Niklas Hallqvist (niklas@appli.se).
 *
 * The original version of this code was written by John Ioannidis
 * for BSD/OS in Athens, Greece, in November 1995.
 *
 * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
 * by Angelos D. Keromytis.
 *
 * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
 * and Niels Provos.
 *
 * Additional features in 1999 by Angelos D. Keromytis and Niklas Hallqvist.
 *
 * Copyright (c) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
 * Angelos D. Keromytis and Niels Provos.
 * Copyright (c) 1999 Niklas Hallqvist.
 * Copyright (c) 2001, Angelos D. Keromytis.
 *
 * Permission to use, copy, and modify this software with or without fee
 * is hereby granted, provided that this entire notice is included in
 * all copies of any software which is or includes a copy or
 * modification of this software.
 * You may use this code under the GNU public license if you so wish. Please
 * contribute changes back to the authors under this freer than GPL license
 * so that we may further the use of strong encryption without limitations to
 * all.
 *
 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
 * PURPOSE.
 */

#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>

#include <net/if.h>
#include <net/route.h>

#ifdef INET
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#endif /* INET */

#ifdef INET6
#ifndef INET
#include <netinet/in.h>
#endif
#include <netinet6/in6_var.h>
#endif /* INET6 */

#include <netinet/ip_ipsp.h>
#include <net/pfkeyv2.h>
#include <crypto/xform.h>
#include <dev/rndvar.h>

#ifdef DDB
#include <ddb/db_output.h>
void tdb_hashstats(void);
#endif

#ifdef ENCDEBUG
#define	DPRINTF(x)	if (encdebug) printf x
#else
#define	DPRINTF(x)
#endif

#ifdef __GNUC__
#define	INLINE	static __inline
#endif

int		ipsp_kern __P((int, char **, int));
u_int8_t	get_sa_require  __P((struct inpcb *));
void		tdb_rehash __P((void));
void		tdb_timeout __P((void *v));
void		tdb_firstuse __P((void *v));
void		tdb_soft_timeout __P((void *v));
void		tdb_soft_firstuse __P((void *v));

extern int	ipsec_auth_default_level;
extern int	ipsec_esp_trans_default_level;
extern int	ipsec_esp_network_default_level;
extern int	ipsec_ipcomp_default_level;

extern int encdebug;
int ipsec_in_use = 0;
u_int64_t ipsec_last_added = 0;
u_int32_t kernfs_epoch = 0;

struct ipsec_policy_head ipsec_policy_head =
    TAILQ_HEAD_INITIALIZER(ipsec_policy_head);
struct ipsec_acquire_head ipsec_acquire_head =
    TAILQ_HEAD_INITIALIZER(ipsec_acquire_head);

/*
 * This is the proper place to define the various encapsulation transforms.
 */

struct xformsw xformsw[] = {
	{ XF_IP4,	     0,               "IPv4 Simple Encapsulation",
	  ipe4_attach,       ipe4_init,       ipe4_zeroize,
	  (int (*)(struct mbuf *, struct tdb *, int, int))ipe4_input,
	  ipip_output, },
	{ XF_AH,	 XFT_AUTH,	    "IPsec AH",
	  ah_attach,	ah_init,   ah_zeroize,
	  ah_input,	 	ah_output, },
	{ XF_ESP,	 XFT_CONF|XFT_AUTH, "IPsec ESP",
	  esp_attach,	esp_init,  esp_zeroize,
	  esp_input,	esp_output, },
	{ XF_IPCOMP,	XFT_COMP, "IPcomp",
	  ipcomp_attach,    ipcomp_init, ipcomp_zeroize,
	  ipcomp_input,     ipcomp_output, },
#ifdef TCP_SIGNATURE
	{ XF_TCPSIGNATURE,	 XFT_AUTH, "TCP MD5 Signature Option, RFC 2385",
	  tcp_signature_tdb_attach, 	tcp_signature_tdb_init,
	  tcp_signature_tdb_zeroize,	tcp_signature_tdb_input,
	  tcp_signature_tdb_output, }
#endif /* TCP_SIGNATURE */
};

struct xformsw *xformswNXFORMSW = &xformsw[sizeof(xformsw)/sizeof(xformsw[0])];

unsigned char ipseczeroes[IPSEC_ZEROES_SIZE]; /* zeroes! */

#define	TDB_HASHSIZE_INIT	32

static struct tdb **tdbh = NULL;
static struct tdb **tdbaddr = NULL;
static struct tdb **tdbsrc = NULL;
static u_int tdb_hashmask = TDB_HASHSIZE_INIT - 1;
static int tdb_count;

/*
 * Our hashing function needs to stir things with a non-zero random multiplier
 * so we cannot be DoS-attacked via choosing of the data to hash.
 */
INLINE int
tdb_hash(u_int32_t spi, union sockaddr_union *dst, u_int8_t proto)
{
	static u_int32_t mult1 = 0, mult2 = 0;
	u_int8_t *ptr = (u_int8_t *) dst;
	int i, shift;
	u_int64_t hash;
	int val32 = 0;

	while (mult1 == 0)
		mult1 = arc4random();
	while (mult2 == 0)
		mult2 = arc4random();

	hash = (spi ^ proto) * mult1;
	for (i = 0; i < SA_LEN(&dst->sa); i++) {
		val32 = (val32 << 8) | ptr[i];
		if (i % 4 == 3) {
			hash ^= val32 * mult2;
			val32 = 0;
		}
	}

	if (i % 4 != 0)
		hash ^= val32 * mult2;

	shift = ffs(tdb_hashmask + 1);
	while ((hash & ~tdb_hashmask) != 0)
		hash = (hash >> shift) ^ (hash & tdb_hashmask);

	return hash;
}

/*
 * Reserve an SPI; the SA is not valid yet though.  We use 0 as
 * an error return value.
 */
u_int32_t
reserve_spi(u_int32_t sspi, u_int32_t tspi, union sockaddr_union *src,
    union sockaddr_union *dst, u_int8_t sproto, int *errval)
{
	struct tdb *tdbp;
	u_int32_t spi;
	int nums, s;

	/* Don't accept ranges only encompassing reserved SPIs. */
	if (sproto != IPPROTO_IPCOMP && 
	    (tspi < sspi || tspi <= SPI_RESERVED_MAX)) {
		(*errval) = EINVAL;
		return 0;
	}
	if (sproto == IPPROTO_IPCOMP && (tspi < sspi ||
	    tspi <= CPI_RESERVED_MAX ||
	    tspi >= CPI_PRIVATE_MIN)) {
		(*errval) = EINVAL;
		return 0;
	}

	/* Limit the range to not include reserved areas. */
	if (sspi <= SPI_RESERVED_MAX)
		sspi = SPI_RESERVED_MAX + 1;

	/* For IPCOMP the CPI is only 16 bits long, what a good idea.... */

	if (sproto == IPPROTO_IPCOMP) {
		u_int32_t t;
		if (sspi >= 0x10000)
			sspi = 0xffff;
		if (tspi >= 0x10000)
			tspi = 0xffff;
		if (sspi > tspi) {
			t = sspi; sspi = tspi; tspi = t;
		}
	}

	if (sspi == tspi)   /* Asking for a specific SPI. */
		nums = 1;
	else
		nums = 100;  /* Arbitrarily chosen */

	while (nums--) {
		if (sspi == tspi)  /* Specific SPI asked. */
			spi = tspi;
		else    /* Range specified */
			spi = sspi + (arc4random() % (tspi - sspi));

		/* Don't allocate reserved SPIs.  */
		if (spi >= SPI_RESERVED_MIN && spi <= SPI_RESERVED_MAX)
			continue;
		else
			spi = htonl(spi);

		/* Check whether we're using this SPI already. */
		s = spltdb();
		tdbp = gettdb(spi, dst, sproto);
		splx(s);

		if (tdbp != (struct tdb *) NULL)
			continue;

		tdbp = tdb_alloc();

		tdbp->tdb_spi = spi;
		bcopy(&dst->sa, &tdbp->tdb_dst.sa, SA_LEN(&dst->sa));
		bcopy(&src->sa, &tdbp->tdb_src.sa, SA_LEN(&src->sa));
		tdbp->tdb_sproto = sproto;
		tdbp->tdb_flags |= TDBF_INVALID; /* Mark SA invalid for now. */
		tdbp->tdb_satype = SADB_SATYPE_UNSPEC;
		puttdb(tdbp);

		/* Setup a "silent" expiration (since TDBF_INVALID's set). */
		if (ipsec_keep_invalid > 0) {
			tdbp->tdb_flags |= TDBF_TIMER;
			tdbp->tdb_exp_timeout = ipsec_keep_invalid;
			timeout_add(&tdbp->tdb_timer_tmo,
			    hz * ipsec_keep_invalid);
		}

		return spi;
	}

	(*errval) = EEXIST;
	return 0;
}

/*
 * An IPSP SAID is really the concatenation of the SPI found in the
 * packet, the destination address of the packet and the IPsec protocol.
 * When we receive an IPSP packet, we need to look up its tunnel descriptor
 * block, based on the SPI in the packet and the destination address (which
 * is really one of our addresses if we received the packet!
 *
 * Caller is responsible for setting at least spltdb().
 */
struct tdb *
gettdb(u_int32_t spi, union sockaddr_union *dst, u_int8_t proto)
{
	u_int32_t hashval;
	struct tdb *tdbp;

	if (tdbh == NULL)
		return (struct tdb *) NULL;

	hashval = tdb_hash(spi, dst, proto);

	for (tdbp = tdbh[hashval]; tdbp != NULL; tdbp = tdbp->tdb_hnext)
		if ((tdbp->tdb_spi == spi) &&
		    !bcmp(&tdbp->tdb_dst, dst, SA_LEN(&dst->sa)) &&
		    (tdbp->tdb_sproto == proto))
			break;

	return tdbp;
}

/*
 * Get an SA given the remote address, the security protocol type, and
 * the desired IDs.
 */
struct tdb *
gettdbbyaddr(union sockaddr_union *dst, struct ipsec_policy *ipo,
    struct mbuf *m, int af)
{
	u_int32_t hashval;
	struct tdb *tdbp;

	if (tdbaddr == NULL)
		return (struct tdb *) NULL;

	hashval = tdb_hash(0, dst, ipo->ipo_sproto);

	for (tdbp = tdbaddr[hashval]; tdbp != NULL; tdbp = tdbp->tdb_anext)
		if ((tdbp->tdb_sproto == ipo->ipo_sproto) &&
		    ((tdbp->tdb_flags & TDBF_INVALID) == 0) &&
		    (!bcmp(&tdbp->tdb_dst, dst, SA_LEN(&dst->sa)))) {
			/*
			 * If the IDs are not set, this was probably a
			 * manually-keyed SA, so it can be used for
			 * any type of traffic.
			 */
			if (tdbp->tdb_srcid != NULL) {
				if (ipo->ipo_srcid != NULL &&
				    !ipsp_ref_match(ipo->ipo_srcid,
					tdbp->tdb_srcid))
					continue;
				/* Otherwise, this is fine. */
			}

			if (tdbp->tdb_dstid != NULL) {
				if (ipo->ipo_dstid != NULL &&
				    !ipsp_ref_match(ipo->ipo_dstid,
					tdbp->tdb_dstid))
					continue;
				/* Otherwise, this is fine. */
			}

			/* Check for credential matches. */
			if (tdbp->tdb_local_cred != NULL) {
				if (ipo->ipo_local_cred != NULL &&
				    !ipsp_ref_match(ipo->ipo_local_cred,
					tdbp->tdb_local_cred))
					continue;
			} else if (ipo->ipo_local_cred != NULL)
				continue; /* If no credential was used
					   * in the TDB, try to
					   * establish a new SA with
					   * the given credential,
					   * since some type of access
					   * control may be done on
					   * the other side based on
					   * that credential.
					   */

			/* XXX Check for filter matches. */
			break;
		}

	return tdbp;
}

/*
 * Get an SA given the source address, the security protocol type, and
 * the desired IDs.
 */
struct tdb *
gettdbbysrc(union sockaddr_union *src, struct ipsec_policy *ipo,
    struct mbuf *m, int af)
{
	u_int32_t hashval;
	struct tdb *tdbp;

	if (tdbsrc == NULL)
		return (struct tdb *) NULL;

	hashval = tdb_hash(0, src, ipo->ipo_sproto);

	for (tdbp = tdbsrc[hashval]; tdbp != NULL; tdbp = tdbp->tdb_snext)
		if ((tdbp->tdb_sproto == ipo->ipo_sproto) &&
		    ((tdbp->tdb_flags & TDBF_INVALID) == 0) &&
		    (!bcmp(&tdbp->tdb_src, src, SA_LEN(&src->sa)))) {
			/*
			 * If the IDs are not set, this was probably a
			 * manually-keyed SA, so it can be used for
			 * any type of traffic.
			 */
			if (tdbp->tdb_srcid != NULL) {
				if (ipo->ipo_dstid != NULL &&
				    !ipsp_ref_match(ipo->ipo_dstid,
					tdbp->tdb_srcid))
					continue;
				/* Otherwise, this is fine. */
			}

			if (tdbp->tdb_dstid != NULL) {
				if (ipo->ipo_srcid != NULL &&
				    !ipsp_ref_match(ipo->ipo_srcid,
					tdbp->tdb_dstid))
					continue;
				/* Otherwise, this is fine. */
			}

			/* XXX Check for filter matches. */
			break;
		}

	return tdbp;
}

#if DDB
void
tdb_hashstats(void)
{
	int i, cnt, buckets[16];
	struct tdb *tdbp;

	if (tdbh == NULL) {
		db_printf("no tdb hash table\n");
		return;
	}

	bzero (buckets, sizeof(buckets));
	for (i = 0; i <= tdb_hashmask; i++) {
		cnt = 0;
		for (tdbp = tdbh[i]; cnt < 16 && tdbp != NULL;
		    tdbp = tdbp->tdb_hnext)
			cnt++;
		buckets[cnt]++;
	}

	db_printf("tdb cnt\t\tbucket cnt\n");
	for (i = 0; i < 16; i++)
		if (buckets[i] > 0)
			db_printf("%d%c\t\t%d\n", i, i == 15 ? "+" : "",
			    buckets[i]);
}
#endif	/* DDB */

/*
 * Caller is responsible for setting at least spltdb().
 */
int
tdb_walk(int (*walker)(struct tdb *, void *, int), void *arg)
{
	int i, rval = 0;
	struct tdb *tdbp, *next;

	if (tdbh == NULL)
		return ENOENT;

	for (i = 0; i <= tdb_hashmask; i++)
		for (tdbp = tdbh[i]; rval == 0 && tdbp != NULL; tdbp = next) {
			next = tdbp->tdb_hnext;
			if (i == tdb_hashmask && next == NULL)
				rval = walker(tdbp, (void *)arg, 1);
			else
				rval = walker(tdbp, (void *)arg, 0);
		}

	return rval;
}

/*
 * Called at splsoftclock().
 */
void
tdb_timeout(void *v)
{
	struct tdb *tdb = v;

	if (!(tdb->tdb_flags & TDBF_TIMER))
		return;

	/* If it's an "invalid" TDB do a silent expiration. */
	if (!(tdb->tdb_flags & TDBF_INVALID))
		pfkeyv2_expire(tdb, SADB_EXT_LIFETIME_HARD);
	tdb_delete(tdb);
}

void
tdb_firstuse(void *v)
{
	struct tdb *tdb = v;

	if (!(tdb->tdb_flags & TDBF_SOFT_FIRSTUSE))
		return;

	/* If the TDB hasn't been used, don't renew it. */
	if (tdb->tdb_first_use != 0)
		pfkeyv2_expire(tdb, SADB_EXT_LIFETIME_HARD);
	tdb_delete(tdb);
}

void
tdb_soft_timeout(void *v)
{
	struct tdb *tdb = v;

	if (!(tdb->tdb_flags & TDBF_SOFT_TIMER))
		return;

	/* Soft expirations. */
	pfkeyv2_expire(tdb, SADB_EXT_LIFETIME_SOFT);
	tdb->tdb_flags &= ~TDBF_SOFT_TIMER;
}

void
tdb_soft_firstuse(void *v)
{
	struct tdb *tdb = v;

	if (!(tdb->tdb_flags & TDBF_SOFT_FIRSTUSE))
		return;

	/* If the TDB hasn't been used, don't renew it. */
	if (tdb->tdb_first_use != 0)
		pfkeyv2_expire(tdb, SADB_EXT_LIFETIME_SOFT);
	tdb->tdb_flags &= ~TDBF_SOFT_FIRSTUSE;
}

/*
 * Caller is responsible for spltdb().
 */
void
tdb_rehash(void)
{
	struct tdb **new_tdbh, **new_tdbaddr, **new_srcaddr, *tdbp, *tdbnp;
	u_int i, old_hashmask = tdb_hashmask;
	u_int32_t hashval;

	tdb_hashmask = (tdb_hashmask << 1) | 1;

	MALLOC(new_tdbh, struct tdb **,
	    sizeof(struct tdb *) * (tdb_hashmask + 1), M_TDB, M_WAITOK);
	MALLOC(new_tdbaddr, struct tdb **,
	    sizeof(struct tdb *) * (tdb_hashmask + 1), M_TDB, M_WAITOK);
	MALLOC(new_srcaddr, struct tdb **,
	    sizeof(struct tdb *) * (tdb_hashmask + 1), M_TDB, M_WAITOK);

	bzero(new_tdbh, sizeof(struct tdb *) * (tdb_hashmask + 1));
	bzero(new_tdbaddr, sizeof(struct tdb *) * (tdb_hashmask + 1));
	bzero(new_srcaddr, sizeof(struct tdb *) * (tdb_hashmask + 1));

	for (i = 0; i <= old_hashmask; i++) {
		for (tdbp = tdbh[i]; tdbp != NULL; tdbp = tdbnp) {
			tdbnp = tdbp->tdb_hnext;
			hashval = tdb_hash(tdbp->tdb_spi, &tdbp->tdb_dst,
			    tdbp->tdb_sproto);
			tdbp->tdb_hnext = new_tdbh[hashval];
			new_tdbh[hashval] = tdbp;
		}

		for (tdbp = tdbaddr[i]; tdbp != NULL; tdbp = tdbnp) {
			tdbnp = tdbp->tdb_anext;
			hashval = tdb_hash(0, &tdbp->tdb_dst,
			    tdbp->tdb_sproto);
			tdbp->tdb_anext = new_tdbaddr[hashval];
			new_tdbaddr[hashval] = tdbp;
		}

		for (tdbp = tdbsrc[i]; tdbp != NULL; tdbp = tdbnp) {
			tdbnp = tdbp->tdb_snext;
			hashval = tdb_hash(0, &tdbp->tdb_src,
			    tdbp->tdb_sproto);
			tdbp->tdb_snext = new_srcaddr[hashval];
			new_srcaddr[hashval] = tdbp;
		}
	}

	FREE(tdbh, M_TDB);
	tdbh = new_tdbh;

	FREE(tdbaddr, M_TDB);
	tdbaddr = new_tdbaddr;

	FREE(tdbsrc, M_TDB);
	tdbsrc = new_srcaddr;
}

/*
 * Add TDB in the hash table.
 */
void
puttdb(struct tdb *tdbp)
{
	u_int32_t hashval;
	int s = spltdb();

	if (tdbh == NULL) {
		MALLOC(tdbh, struct tdb **,
		    sizeof(struct tdb *) * (tdb_hashmask + 1),
		    M_TDB, M_WAITOK);
		MALLOC(tdbaddr, struct tdb **,
		    sizeof(struct tdb *) * (tdb_hashmask + 1),
		    M_TDB, M_WAITOK);
		MALLOC(tdbsrc, struct tdb **,
		    sizeof(struct tdb *) * (tdb_hashmask + 1),
		    M_TDB, M_WAITOK);

		bzero(tdbh, sizeof(struct tdb *) * (tdb_hashmask + 1));
		bzero(tdbaddr, sizeof(struct tdb *) * (tdb_hashmask + 1));
		bzero(tdbsrc, sizeof(struct tdb *) * (tdb_hashmask + 1));
	}

	hashval = tdb_hash(tdbp->tdb_spi, &tdbp->tdb_dst, tdbp->tdb_sproto);

	/*
	 * Rehash if this tdb would cause a bucket to have more than
	 * two items and if the number of tdbs exceed 10% of the
	 * bucket count.  This number is arbitratily chosen and is
	 * just a measure to not keep rehashing when adding and
	 * removing tdbs which happens to always end up in the same
	 * bucket, which is not uncommon when doing manual keying.
	 */
	if (tdbh[hashval] != NULL && tdbh[hashval]->tdb_hnext != NULL &&
	    tdb_count * 10 > tdb_hashmask + 1) {
		tdb_rehash();
		hashval = tdb_hash(tdbp->tdb_spi, &tdbp->tdb_dst,
		    tdbp->tdb_sproto);
	}

	tdbp->tdb_hnext = tdbh[hashval];
	tdbh[hashval] = tdbp;

	hashval = tdb_hash(0, &tdbp->tdb_dst, tdbp->tdb_sproto);
	tdbp->tdb_anext = tdbaddr[hashval];
	tdbaddr[hashval] = tdbp;

	hashval = tdb_hash(0, &tdbp->tdb_src, tdbp->tdb_sproto);
	tdbp->tdb_snext = tdbsrc[hashval];
	tdbsrc[hashval] = tdbp;

	tdb_count++;

	ipsec_last_added = time.tv_sec;

	splx(s);
}

/*
 * Caller is responsible to set at least spltdb().
 */
void
tdb_delete(struct tdb *tdbp)
{
	struct ipsec_policy *ipo;
	struct tdb *tdbpp;
	struct inpcb *inp;
	u_int32_t hashval;
	int s;

	if (tdbh == NULL)
		return;

	hashval = tdb_hash(tdbp->tdb_spi, &tdbp->tdb_dst, tdbp->tdb_sproto);

	s = spltdb();
	if (tdbh[hashval] == tdbp) {
		tdbpp = tdbp;
		tdbh[hashval] = tdbp->tdb_hnext;
	} else {
		for (tdbpp = tdbh[hashval]; tdbpp != NULL;
		    tdbpp = tdbpp->tdb_hnext) {
			if (tdbpp->tdb_hnext == tdbp) {
				tdbpp->tdb_hnext = tdbp->tdb_hnext;
				tdbpp = tdbp;
				break;
			}
		}
	}

	tdbp->tdb_hnext = NULL;

	hashval = tdb_hash(0, &tdbp->tdb_dst, tdbp->tdb_sproto);

	if (tdbaddr[hashval] == tdbp) {
		tdbpp = tdbp;
		tdbaddr[hashval] = tdbp->tdb_anext;
	} else {
		for (tdbpp = tdbaddr[hashval]; tdbpp != NULL;
		    tdbpp = tdbpp->tdb_anext) {
			if (tdbpp->tdb_anext == tdbp) {
				tdbpp->tdb_anext = tdbp->tdb_anext;
				tdbpp = tdbp;
				break;
			}
		}
	}

	hashval = tdb_hash(0, &tdbp->tdb_src, tdbp->tdb_sproto);

	if (tdbsrc[hashval] == tdbp) {
		tdbpp = tdbp;
		tdbsrc[hashval] = tdbp->tdb_snext;
	}
	else {
		for (tdbpp = tdbsrc[hashval]; tdbpp != NULL;
		    tdbpp = tdbpp->tdb_snext) {
			if (tdbpp->tdb_snext == tdbp) {
				tdbpp->tdb_snext = tdbp->tdb_snext;
				tdbpp = tdbp;
				break;
			}
		}
	}

	tdbp->tdb_snext = NULL;

	if (tdbp->tdb_xform) {
		(*(tdbp->tdb_xform->xf_zeroize))(tdbp);
		tdbp->tdb_xform = NULL;
	}

	/* Cleanup inp references. */
	for (inp = TAILQ_FIRST(&tdbp->tdb_inp_in); inp;
	    inp = TAILQ_FIRST(&tdbp->tdb_inp_in)) {
		TAILQ_REMOVE(&tdbp->tdb_inp_in, inp, inp_tdb_in_next);
		inp->inp_tdb_in = NULL;
	}

	for (inp = TAILQ_FIRST(&tdbp->tdb_inp_out); inp;
	    inp = TAILQ_FIRST(&tdbp->tdb_inp_out)) {
		TAILQ_REMOVE(&tdbp->tdb_inp_out, inp, inp_tdb_out_next);
		inp->inp_tdb_out = NULL;
	}

	/* Cleanup SPD references. */
	for (ipo = TAILQ_FIRST(&tdbp->tdb_policy_head); ipo;
	    ipo = TAILQ_FIRST(&tdbp->tdb_policy_head))	{
		TAILQ_REMOVE(&tdbp->tdb_policy_head, ipo, ipo_tdb_next);
		ipo->ipo_tdb = NULL;
		ipo->ipo_last_searched = 0; /* Force a re-search. */
	}

	/* Remove expiration timeouts. */
	tdbp->tdb_flags &= ~(TDBF_FIRSTUSE | TDBF_SOFT_FIRSTUSE | TDBF_TIMER |
	    TDBF_SOFT_TIMER);
	timeout_del(&tdbp->tdb_timer_tmo);
	timeout_del(&tdbp->tdb_first_tmo);
	timeout_del(&tdbp->tdb_stimer_tmo);
	timeout_del(&tdbp->tdb_sfirst_tmo);

	if (tdbp->tdb_local_auth) {
		ipsp_reffree(tdbp->tdb_local_auth);
		tdbp->tdb_local_auth = NULL;
	}

	if (tdbp->tdb_remote_auth) {
		ipsp_reffree(tdbp->tdb_remote_auth);
		tdbp->tdb_remote_auth = NULL;
	}

	if (tdbp->tdb_srcid) {
		ipsp_reffree(tdbp->tdb_srcid);
		tdbp->tdb_srcid = NULL;
	}

	if (tdbp->tdb_dstid) {
		ipsp_reffree(tdbp->tdb_dstid);
		tdbp->tdb_dstid = NULL;
	}

	if (tdbp->tdb_local_cred) {
		ipsp_reffree(tdbp->tdb_local_cred);
		tdbp->tdb_local_cred = NULL;
	}

	if (tdbp->tdb_remote_cred) {
		ipsp_reffree(tdbp->tdb_remote_cred);
		tdbp->tdb_local_cred = NULL;
	}

	if ((tdbp->tdb_onext) && (tdbp->tdb_onext->tdb_inext == tdbp))
		tdbp->tdb_onext->tdb_inext = NULL;

	if ((tdbp->tdb_inext) && (tdbp->tdb_inext->tdb_onext == tdbp))
		tdbp->tdb_inext->tdb_onext = NULL;

	FREE(tdbp, M_TDB);
	tdb_count--;

	splx(s);
}

/*
 * Allocate a TDB and initialize a few basic fields.
 */
struct tdb *
tdb_alloc(void)
{
	struct tdb *tdbp;

	MALLOC(tdbp, struct tdb *, sizeof(struct tdb), M_TDB, M_WAITOK);
	bzero((caddr_t) tdbp, sizeof(struct tdb));

	/* Init Incoming SA-Binding Queues. */
	TAILQ_INIT(&tdbp->tdb_inp_out);
	TAILQ_INIT(&tdbp->tdb_inp_in);

	TAILQ_INIT(&tdbp->tdb_policy_head);

	/* Record establishment time. */
	tdbp->tdb_established = time.tv_sec;
	tdbp->tdb_epoch = kernfs_epoch - 1;

	/* Initialize timeouts. */
	timeout_set(&tdbp->tdb_timer_tmo, tdb_timeout, tdbp);
	timeout_set(&tdbp->tdb_first_tmo, tdb_firstuse, tdbp);
	timeout_set(&tdbp->tdb_stimer_tmo, tdb_soft_timeout, tdbp);
	timeout_set(&tdbp->tdb_sfirst_tmo, tdb_soft_firstuse, tdbp);

	return tdbp;
}

/*
 * Do further initializations of a TDB.
 */
int
tdb_init(struct tdb *tdbp, u_int16_t alg, struct ipsecinit *ii)
{
	struct xformsw *xsp;
	int err;

	for (xsp = xformsw; xsp < xformswNXFORMSW; xsp++) {
		if (xsp->xf_type == alg) {
			err = (*(xsp->xf_init))(tdbp, xsp, ii);
			return err;
		}
	}

	DPRINTF(("tdb_init(): no alg %d for spi %08x, addr %s, proto %d\n",
	    alg, ntohl(tdbp->tdb_spi), ipsp_address(tdbp->tdb_dst),
	    tdbp->tdb_sproto));

	return EINVAL;
}

#ifdef KERNFS
/*
 * Print TDB information on a buffer.
 */
int
ipsp_print_tdb(struct tdb *tdb, char *buffer)
{
	int l, i, k;
	struct ctlname ipspflags[] = {
		{ "unique", TDBF_UNIQUE },
		{ "invalid", TDBF_INVALID },
		{ "halfiv", TDBF_HALFIV },
		{ "pfs", TDBF_PFS },
		{ "tunneling", TDBF_TUNNELING },
		{ "noreplay", TDBF_NOREPLAY },
		{ "random padding", TDBF_RANDOMPADDING },
		{ "skipcrypto", TDBF_SKIPCRYPTO },
		{ "usedtunnel", TDBF_USEDTUNNEL },
	};

	l = sprintf(buffer,  "SPI = %08x, Destination = %s, Sproto = %u\n",
	    ntohl(tdb->tdb_spi), ipsp_address(tdb->tdb_dst), tdb->tdb_sproto);

	l += sprintf(buffer + l, "\tEstablished %d seconds ago\n",
	    time.tv_sec - tdb->tdb_established);

	l += sprintf(buffer + l, "\tSource = %s", ipsp_address(tdb->tdb_src));

	if (tdb->tdb_proxy.sa.sa_family)
		l += sprintf(buffer + l, ", Proxy = %s\n",
		    ipsp_address(tdb->tdb_proxy));
	else
		l += sprintf(buffer + l, "\n");

	if (tdb->tdb_mtu && tdb->tdb_mtutimeout > time.tv_sec)
		l += sprintf(buffer + l, "\tMTU: %d, expires in %llu seconds\n",
		    tdb->tdb_mtu, tdb->tdb_mtutimeout - time.tv_sec);

	if (tdb->tdb_local_cred)
		l += sprintf(buffer + l, "\tLocal credential type %d\n",
		    ((struct ipsec_ref *) tdb->tdb_local_cred)->ref_type);

	if (tdb->tdb_remote_cred)
		l += sprintf(buffer + l, "\tRemote credential type %d\n",
		    ((struct ipsec_ref *) tdb->tdb_remote_cred)->ref_type);

	if (tdb->tdb_local_auth)
		l += sprintf(buffer + l, "\tLocal auth type %d\n",
		    ((struct ipsec_ref *) tdb->tdb_local_auth)->ref_type);

	if (tdb->tdb_remote_auth)
		l += sprintf(buffer + l, "\tRemote auth type %d\n",
		    ((struct ipsec_ref *) tdb->tdb_remote_auth)->ref_type);

	l += sprintf(buffer + l, "\tFlags (%08x) = <", tdb->tdb_flags);

	if ((tdb->tdb_flags & ~(TDBF_TIMER | TDBF_BYTES | TDBF_ALLOCATIONS |
	    TDBF_FIRSTUSE | TDBF_SOFT_TIMER | TDBF_SOFT_BYTES |
	    TDBF_SOFT_FIRSTUSE | TDBF_SOFT_ALLOCATIONS)) == 0)
		l += sprintf(buffer + l, "none>\n");
	else {
		for (k = 0, i = 0;
		    k < sizeof(ipspflags) / sizeof(struct ctlname); k++) {
			if (tdb->tdb_flags & ipspflags[k].ctl_type) {
				l += sprintf(buffer + l, "%s,",
				    ipspflags[k].ctl_name);
				i = 1;
			}
		}

		/* If we added flags, remove trailing comma. */
		if (i)
			l--;
		l += sprintf(buffer + l, ">\n");
	}

	l += sprintf(buffer + l, "\tCrypto ID: %llu\n", tdb->tdb_cryptoid);

	if (tdb->tdb_xform)
		l += sprintf(buffer + l, "\txform = <%s>\n",
		    tdb->tdb_xform->xf_name);

	if (tdb->tdb_encalgxform)
		l += sprintf(buffer + l, "\t\tEncryption = <%s>\n",
		    tdb->tdb_encalgxform->name);

	if (tdb->tdb_authalgxform)
		l += sprintf(buffer + l, "\t\tAuthentication = <%s>\n",
		    tdb->tdb_authalgxform->name);

	if (tdb->tdb_compalgxform)
		l += sprintf(buffer + l, "\t\tCompression = <%s>\n",
		    tdb->tdb_compalgxform->name);

	if (tdb->tdb_onext)
		l += sprintf(buffer + l,
		    "\tNext SA: SPI = %08x, Destination = %s, Sproto = %u\n",
		    ntohl(tdb->tdb_onext->tdb_spi),
		    ipsp_address(tdb->tdb_onext->tdb_dst),
		    tdb->tdb_onext->tdb_sproto);

	if (tdb->tdb_inext)
		l += sprintf(buffer + l, "\tPrevious SA: SPI = %08x, "
		    "Destination = %s, Sproto = %u\n",
		    ntohl(tdb->tdb_inext->tdb_spi),
		    ipsp_address(tdb->tdb_inext->tdb_dst),
		    tdb->tdb_inext->tdb_sproto);

	l += sprintf(buffer + l, "\t%llu bytes processed by this SA\n",
	    tdb->tdb_cur_bytes);

	if (tdb->tdb_last_used)
		l += sprintf(buffer + l, "\tLast used %llu seconds ago\n",
		    time.tv_sec - tdb->tdb_last_used);

	if (tdb->tdb_last_marked)
		l += sprintf(buffer + l,
		    "\tLast marked/unmarked %llu seconds ago\n",
		    time.tv_sec - tdb->tdb_last_marked);

	l += sprintf(buffer + l, "\tExpirations:\n");

	if (tdb->tdb_flags & TDBF_TIMER)
		l += sprintf(buffer + l,
		    "\t\tHard expiration(1) in %llu seconds\n",
		    tdb->tdb_established + tdb->tdb_exp_timeout - time.tv_sec);

	if (tdb->tdb_flags & TDBF_SOFT_TIMER)
		l += sprintf(buffer + l,
		    "\t\tSoft expiration(1) in %llu seconds\n",
		    tdb->tdb_established + tdb->tdb_soft_timeout -
		    time.tv_sec);

	if (tdb->tdb_flags & TDBF_BYTES)
		l += sprintf(buffer + l,
		    "\t\tHard expiration after %llu bytes\n",
		    tdb->tdb_exp_bytes);

	if (tdb->tdb_flags & TDBF_SOFT_BYTES)
		l += sprintf(buffer + l,
		    "\t\tSoft expiration after %llu bytes\n",
		    tdb->tdb_soft_bytes);

	if (tdb->tdb_flags & TDBF_ALLOCATIONS)
		l += sprintf(buffer + l,
		    "\t\tHard expiration after %u flows\n",
		    tdb->tdb_exp_allocations);

	if (tdb->tdb_flags & TDBF_SOFT_ALLOCATIONS)
		l += sprintf(buffer + l,
		    "\t\tSoft expiration after %u flows\n",
		    tdb->tdb_soft_allocations);

	if (tdb->tdb_flags & TDBF_FIRSTUSE) {
		if (tdb->tdb_first_use)
			l += sprintf(buffer + l,
			    "\t\tHard expiration(2) in %llu seconds\n",
			    (tdb->tdb_first_use + tdb->tdb_exp_first_use) -
			    time.tv_sec);
		else
			l += sprintf(buffer + l,
			    "\t\tHard expiration in %llu seconds "
			    "after first use\n",
			    tdb->tdb_exp_first_use);
	}

	if (tdb->tdb_flags & TDBF_SOFT_FIRSTUSE) {
		if (tdb->tdb_first_use)
			l += sprintf(buffer + l,
			    "\t\tSoft expiration(2) in %llu seconds\n",
			    (tdb->tdb_first_use + tdb->tdb_soft_first_use) -
			    time.tv_sec);
		else
			l += sprintf(buffer + l,
			    "\t\tSoft expiration in %llu seconds "
			    "after first use\n", tdb->tdb_soft_first_use);
	}

	if (!(tdb->tdb_flags &
	    (TDBF_TIMER | TDBF_SOFT_TIMER | TDBF_BYTES |
		TDBF_SOFT_ALLOCATIONS | TDBF_ALLOCATIONS |
		TDBF_SOFT_BYTES | TDBF_FIRSTUSE | TDBF_SOFT_FIRSTUSE)))
		l += sprintf(buffer + l, "\t\t(none)\n");

	l += sprintf(buffer + l, "\n");

	return l;
}

/*
 * Used by kernfs.
 */
int
ipsp_kern(int off, char **bufp, int len)
{
	static char buffer[IPSEC_KERNFS_BUFSIZE];
	struct tdb *tdb;
	int i, s, l;

	if (bufp == NULL)
		return 0;

	bzero(buffer, IPSEC_KERNFS_BUFSIZE);
	*bufp = buffer;

	if (off == 0) {
		kernfs_epoch++;
		l = sprintf(buffer, "Hashmask: %d, policy entries: %d\n",
		    tdb_hashmask, ipsec_in_use);
		return l;
	}

	if (tdbh == NULL)
		return 0;

	for (i = 0; i <= tdb_hashmask; i++) {
		s = spltdb();
		for (tdb = tdbh[i]; tdb; tdb = tdb->tdb_hnext) {
			if (tdb->tdb_epoch != kernfs_epoch) {
				tdb->tdb_epoch = kernfs_epoch;
				l = ipsp_print_tdb(tdb, buffer);
				splx(s);
				return l;
			}
		}
		splx(s);
	}
	return 0;
}
#endif /* KERNFS */

/*
 * Check which transformations are required.
 */
u_int8_t
get_sa_require(struct inpcb *inp)
{
	u_int8_t sareq = 0;

	if (inp != NULL) {
		sareq |= inp->inp_seclevel[SL_AUTH] >= IPSEC_LEVEL_USE ?
		    NOTIFY_SATYPE_AUTH : 0;
		sareq |= inp->inp_seclevel[SL_ESP_TRANS] >= IPSEC_LEVEL_USE ?
		    NOTIFY_SATYPE_CONF : 0;
		sareq |= inp->inp_seclevel[SL_ESP_NETWORK] >= IPSEC_LEVEL_USE ?
		    NOTIFY_SATYPE_TUNNEL : 0;
	} else {
		sareq |= ipsec_auth_default_level >= IPSEC_LEVEL_USE ?
		    NOTIFY_SATYPE_AUTH : 0;
		sareq |= ipsec_esp_trans_default_level >= IPSEC_LEVEL_USE ?
		    NOTIFY_SATYPE_CONF : 0;
		sareq |= ipsec_esp_network_default_level >= IPSEC_LEVEL_USE ?
		    NOTIFY_SATYPE_TUNNEL : 0;
	}

	return (sareq);
}

/*
 * Add an inpcb to the list of inpcb which reference this tdb directly.
 */
void
tdb_add_inp(struct tdb *tdb, struct inpcb *inp, int inout)
{
	if (inout) {
		if (inp->inp_tdb_in) {
			if (inp->inp_tdb_in == tdb)
				return;

			TAILQ_REMOVE(&inp->inp_tdb_in->tdb_inp_in, inp,
			    inp_tdb_in_next);
		}

		inp->inp_tdb_in = tdb;
		TAILQ_INSERT_TAIL(&tdb->tdb_inp_in, inp, inp_tdb_in_next);
	} else {
		if (inp->inp_tdb_out) {
			if (inp->inp_tdb_out == tdb)
				return;

			TAILQ_REMOVE(&inp->inp_tdb_out->tdb_inp_out, inp,
			    inp_tdb_out_next);
		}

		inp->inp_tdb_out = tdb;
		TAILQ_INSERT_TAIL(&tdb->tdb_inp_out, inp, inp_tdb_out_next);
	}
}

/* Return a printable string for the IPv4 address. */
char *
inet_ntoa4(struct in_addr ina)
{
	static char buf[4][4 * sizeof "123" + 4];
	unsigned char *ucp = (unsigned char *) &ina;
	static int i = 3;

	i = (i + 1) % 4;
	sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff,
	    ucp[2] & 0xff, ucp[3] & 0xff);
	return (buf[i]);
}

/* Return a printable string for the address. */
char *
ipsp_address(union sockaddr_union sa)
{
	switch (sa.sa.sa_family) {
#if INET
	case AF_INET:
		return inet_ntoa4(sa.sin.sin_addr);
#endif /* INET */

#if INET6
	case AF_INET6:
		return ip6_sprintf(&sa.sin6.sin6_addr);
#endif /* INET6 */

	default:
		return "(unknown address family)";
	}
}

/* Check whether an IP{4,6} address is unspecified. */
int
ipsp_is_unspecified(union sockaddr_union addr)
{
	switch (addr.sa.sa_family) {
#ifdef INET
	case AF_INET:
		if (addr.sin.sin_addr.s_addr == INADDR_ANY)
			return 1;
		else
			return 0;
#endif /* INET */

#ifdef INET6
	case AF_INET6:
		if (IN6_IS_ADDR_UNSPECIFIED(&addr.sin6.sin6_addr))
			return 1;
		else
			return 0;
#endif /* INET6 */

	case 0: /* No family set. */
	default:
		return 1;
	}
}

/* Free reference-counted structure. */
void
ipsp_reffree(struct ipsec_ref *ipr)
{
#ifdef DIAGNOSTIC
	if (ipr->ref_count <= 0)
		printf("ipsp_reffree: illegal reference count %d for "
		    "object %p (len = %d, malloctype = %d)\n",
		    ipr->ref_count, ipr, ipr->ref_len, ipr->ref_malloctype);
#endif
	if (--ipr->ref_count <= 0)
		FREE(ipr, ipr->ref_malloctype);
}

/* Mark a TDB as TDBF_SKIPCRYPTO. */
void
ipsp_skipcrypto_mark(struct tdb_ident *tdbi)
{
	struct tdb *tdb;
	int s = spltdb();
 
	tdb = gettdb(tdbi->spi, &tdbi->dst, tdbi->proto);
	if (tdb != NULL) {
		tdb->tdb_flags |= TDBF_SKIPCRYPTO;
		tdb->tdb_last_marked = time.tv_sec;
	}
	splx(s);
}

/* Unmark a TDB as TDBF_SKIPCRYPTO. */
void
ipsp_skipcrypto_unmark(struct tdb_ident *tdbi)
{
	struct tdb *tdb;
	int s = spltdb();
 
	tdb = gettdb(tdbi->spi, &tdbi->dst, tdbi->proto);
	if (tdb != NULL) {
		tdb->tdb_flags &= ~TDBF_SKIPCRYPTO;
		tdb->tdb_last_marked = time.tv_sec;
	}
	splx(s);
}

/*
 * Go down a chain of IPv4/IPv6/ESP/AH/IPiP chains creating an tag for each
 * IPsec header encountered. The offset where the first header, as well
 * as its type are given to us.
 */
struct m_tag *
ipsp_parse_headers(struct mbuf *m, int off, u_int8_t proto)
{
	int ipv4sa = 0, s, esphlen = 0, trail = 0, i;
	SLIST_HEAD(packet_tags, m_tag) tags;
	unsigned char lasteight[8];
	struct tdb_ident *tdbi;
	struct m_tag *mtag;
	struct tdb *tdb;

#ifdef INET
	struct ip iph;
#endif /* INET */

#ifdef INET6
	struct in6_addr ip6_dst;
#endif /* INET6 */

	/* We have to start with a known network protocol. */
	if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
		return NULL;

	SLIST_INIT(&tags);

	while (1) {
		switch (proto) {
#ifdef INET
		case IPPROTO_IPV4: /* Also IPPROTO_IPIP */
		{
			/*
			 * Save the IP header (we need both the
			 * address and ip_hl).
			 */
			m_copydata(m, off, sizeof(struct ip), (caddr_t) &iph);
			ipv4sa = 1;
			proto = iph.ip_p;
			off += iph.ip_hl << 2;
			break;
		}
#endif /* INET */

#ifdef INET6
		case IPPROTO_IPV6:
		{
			int nxtp, l;

			/* Copy the IPv6 address. */
			m_copydata(m, off + offsetof(struct ip6_hdr, ip6_dst),
			    sizeof(struct ip6_hdr), (caddr_t) &ip6_dst);
			ipv4sa = 0;

			/*
			 * Go down the chain of headers until we encounter a
			 * non-option.
			 */
			for (l = ip6_nexthdr(m, off, proto, &nxtp); l != -1;
			    l = ip6_nexthdr(m, off, proto, &nxtp)) {
				off += l;
				proto = nxtp;

				/* Construct a tag. */
				if (nxtp == IPPROTO_AH)	{
					mtag = m_tag_get(PACKET_TAG_IPSEC_IN_CRYPTO_DONE,
					    sizeof(struct tdb_ident),
					    M_NOWAIT);

					if (mtag == NULL)
						return tags.slh_first;

					tdbi = (struct tdb_ident *) (mtag + 1);
					bzero(tdbi, sizeof(struct tdb_ident));

					m_copydata(m, off + sizeof(u_int32_t),
					    sizeof(u_int32_t),
					    (caddr_t) &tdbi->spi);

					tdbi->proto = IPPROTO_AH;
					tdbi->dst.sin6.sin6_family = AF_INET6;
					tdbi->dst.sin6.sin6_len =
					    sizeof(struct sockaddr_in6);
					tdbi->dst.sin6.sin6_addr = ip6_dst;
					SLIST_INSERT_HEAD(&tags,
					    mtag, m_tag_link);
				}
				else
					if (nxtp == IPPROTO_IPV6)
						m_copydata(m, off +
						    offsetof(struct ip6_hdr,
							ip6_dst),
						    sizeof(struct ip6_hdr),
						    (caddr_t) &ip6_dst);
			}
			break;
		}
#endif /* INET6 */

		case IPPROTO_ESP:
		/* Verify that this has been decrypted. */
		{
			union sockaddr_union su;
			u_int32_t spi;

			m_copydata(m, off, sizeof(u_int32_t), (caddr_t) &spi);
			bzero(&su, sizeof(union sockaddr_union));

			s = spltdb();

#ifdef INET
			if (ipv4sa) {
				su.sin.sin_family = AF_INET;
				su.sin.sin_len = sizeof(struct sockaddr_in);
				su.sin.sin_addr = iph.ip_dst;
			}
#endif /* INET */

#ifdef INET6
			if (!ipv4sa) {
				su.sin6.sin6_family = AF_INET6;
				su.sin6.sin6_len = sizeof(struct sockaddr_in6);
				su.sin6.sin6_addr = ip6_dst;
			}
#endif /* INET6 */

			tdb = gettdb(spi, &su, IPPROTO_ESP);
			if (tdb == NULL) {
				splx(s);
				return tags.slh_first;
			}

			/* How large is the ESP header ? We use this later. */
			if (tdb->tdb_flags & TDBF_NOREPLAY)
				esphlen = sizeof(u_int32_t) + tdb->tdb_ivlen;
			else
				esphlen = 2 * sizeof(u_int32_t) +
				    tdb->tdb_ivlen;

			/*
			 * Verify decryption. If the SA is using
			 * random padding (as the "old" ESP SAs were
			 * bound to do, there's nothing we can do to
			 * see if the payload has been decrypted.
			 */
			if (tdb->tdb_flags & TDBF_RANDOMPADDING) {
				splx(s);
				return tags.slh_first;
			}

			/* Update the length of trailing ESP authenticators. */
			if (tdb->tdb_authalgxform)
				trail += AH_HMAC_HASHLEN;

			splx(s);

			/* Copy the last 10 bytes. */
			m_copydata(m, m->m_pkthdr.len - trail - 8, 8,
			    lasteight);

			/* Verify the self-describing padding values. */
			if (lasteight[6] != 0) {
				if (lasteight[6] != lasteight[5])
					return tags.slh_first;

				for (i = 4; lasteight[i + 1] != 1 && i >= 0;
				    i--)
					if (lasteight[i + 1] !=
					    lasteight[i] + 1)
						return tags.slh_first;
			}
		}
		/* Fall through. */
		case IPPROTO_AH:
			mtag = m_tag_get(PACKET_TAG_IPSEC_IN_CRYPTO_DONE,
			    sizeof(struct tdb_ident), M_NOWAIT);
			if (mtag == NULL)
				return tags.slh_first;

			tdbi = (struct tdb_ident *) (mtag + 1);
			bzero(tdbi, sizeof(struct tdb_ident));

			/* Get SPI off the relevant header. */
			if (proto == IPPROTO_AH)
				m_copydata(m, off + sizeof(u_int32_t),
				    sizeof(u_int32_t), (caddr_t) &tdbi->spi);
			else /* IPPROTO_ESP */
				m_copydata(m, off, sizeof(u_int32_t),
				    (caddr_t) &tdbi->spi);

			tdbi->proto = proto; /* AH or ESP */

#ifdef INET
			/* Last network header was IPv4. */
			if (ipv4sa) {
				tdbi->dst.sin.sin_family = AF_INET;
				tdbi->dst.sin.sin_len =
				    sizeof(struct sockaddr_in);
				tdbi->dst.sin.sin_addr = iph.ip_dst;
			}
#endif /* INET */

#ifdef INET6
			/* Last network header was IPv6. */
			if (!ipv4sa) {
				tdbi->dst.sin6.sin6_family = AF_INET6;
				tdbi->dst.sin6.sin6_len =
				    sizeof(struct sockaddr_in6);
				tdbi->dst.sin6.sin6_addr = ip6_dst;
			}
#endif /* INET6 */

			SLIST_INSERT_HEAD(&tags, mtag, m_tag_link);

			/* Update next protocol/header and header offset. */
			if (proto == IPPROTO_AH) {
				u_int8_t foo[2];

				m_copydata(m, off, 2 * sizeof(u_int8_t), foo);
				proto = foo[0];
				off += (foo[1] + 2) << 2;
			} else {/* IPPROTO_ESP */
				/* Initialized in IPPROTO_ESP case. */
				off += esphlen;
				proto = lasteight[7];
			}
			break;

		default:
			return tags.slh_first; /* We're done. */
		}
	}
}

/* Return true if the two structures match. */
int
ipsp_ref_match(struct ipsec_ref *ref1, struct ipsec_ref *ref2)
{
	if (ref1->ref_type != ref2->ref_type ||
	    ref1->ref_len != ref2->ref_len ||
	    bcmp(ref1 + 1, ref2 + 1, ref1->ref_len))
		return 0;

	return 1;
}