summaryrefslogtreecommitdiff
path: root/sbin/isakmpd/ike_phase_1.c
blob: d2caa60151ef17c326648bb7e70aab7ced6b57d7 (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
/*	$OpenBSD: ike_phase_1.c,v 1.34 2002/07/04 17:00:35 ho Exp $	*/
/*	$EOM: ike_phase_1.c,v 1.31 2000/12/11 23:47:56 niklas Exp $	*/

/*
 * Copyright (c) 1999, 2000 Niklas Hallqvist.  All rights reserved.
 * Copyright (c) 1999, 2000 Angelos D. Keromytis.  All rights reserved.
 * Copyright (c) 2001 Håkan Olsson.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Ericsson Radio Systems.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * This code was written under funding by Ericsson Radio Systems.
 */

#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <string.h>

#include "sysdep.h"

#include "attribute.h"
#include "conf.h"
#include "constants.h"
#include "crypto.h"
#include "dh.h"
#include "doi.h"
#include "exchange.h"
#include "hash.h"
#include "ike_auth.h"
#include "ike_phase_1.h"
#include "ipsec.h"
#include "ipsec_doi.h"
#include "isakmp.h"
#include "log.h"
#include "math_group.h"
#include "message.h"
#include "prf.h"
#include "sa.h"
#include "transport.h"
#include "util.h"

static int attribute_unacceptable (u_int16_t, u_int8_t *, u_int16_t, void *);
static int ike_phase_1_validate_prop (struct exchange *, struct sa *,
				      struct sa *);

/* Offer a set of transforms to the responder in the MSG message.  */
int
ike_phase_1_initiator_send_SA (struct message *msg)
{
  struct exchange *exchange = msg->exchange;
  struct ipsec_exch *ie = exchange->data;
  u_int8_t *proposal = 0, *sa_buf = 0, *saved_nextp, *attr;
  u_int8_t **transform = 0;
  size_t transforms_len = 0, proposal_len, sa_len;
  size_t *transform_len = 0;
  struct conf_list *conf, *life_conf;
  struct conf_list_node *xf, *life;
  int i, value, update_nextp;
  struct payload *p;
  struct proto *proto;
  int group_desc = -1, new_group_desc;

  /* Get the list of transforms.  */
  conf = conf_get_list (exchange->policy, "Transforms");
  if (!conf)
    return -1;

  transform = calloc (conf->cnt, sizeof *transform);
  if (!transform)
    {
      log_error ("ike_phase_1_initiator_send_SA: calloc (%d, %lu) failed",
		 conf->cnt, (unsigned long)sizeof *transform);
      goto bail_out;
    }

  transform_len = calloc (conf->cnt, sizeof *transform_len);
  if (!transform_len)
    {
      log_error ("ike_phase_1_initiator_send_SA: calloc (%d, %lu) failed",
		 conf->cnt, (unsigned long)sizeof *transform_len);
      goto bail_out;
    }

  for (xf = TAILQ_FIRST (&conf->fields), i = 0; i < conf->cnt;
       i++, xf = TAILQ_NEXT (xf, link))
    {
      /* XXX The sizing needs to be dynamic.  */
      transform[i]
	= malloc (ISAKMP_TRANSFORM_SA_ATTRS_OFF + 16 * ISAKMP_ATTR_VALUE_OFF);
      if (!transform[i])
	{
	  log_error ("ike_phase_1_initiator_send_SA: malloc (%d) failed",
		     ISAKMP_TRANSFORM_SA_ATTRS_OFF
		     + 16 * ISAKMP_ATTR_VALUE_OFF);
	  goto bail_out;
	}

      SET_ISAKMP_TRANSFORM_NO (transform[i], i);
      SET_ISAKMP_TRANSFORM_ID (transform[i], IPSEC_TRANSFORM_KEY_IKE);
      SET_ISAKMP_TRANSFORM_RESERVED (transform[i], 0);

      attr = transform[i] + ISAKMP_TRANSFORM_SA_ATTRS_OFF;

      if (attribute_set_constant (xf->field, "ENCRYPTION_ALGORITHM",
				  ike_encrypt_cst,
				  IKE_ATTR_ENCRYPTION_ALGORITHM, &attr))
	goto bail_out;

      if (attribute_set_constant (xf->field, "HASH_ALGORITHM", ike_hash_cst,
				  IKE_ATTR_HASH_ALGORITHM, &attr))
	goto bail_out;

      if (attribute_set_constant (xf->field, "AUTHENTICATION_METHOD",
				  ike_auth_cst, IKE_ATTR_AUTHENTICATION_METHOD,
				  &attr))
	goto bail_out;

      if (attribute_set_constant (xf->field, "GROUP_DESCRIPTION",
				  ike_group_desc_cst,
				  IKE_ATTR_GROUP_DESCRIPTION, &attr))
	{
	  /*
	   * If no group description exists, try looking for a user-defined
	   * one.
	   */
	  if (attribute_set_constant (xf->field, "GROUP_TYPE", ike_group_cst,
				      IKE_ATTR_GROUP_TYPE, &attr))
	    goto bail_out;

#if 0
	  if (attribute_set_bignum (xf->field, "GROUP_PRIME",
				    IKE_ATTR_GROUP_PRIME, &attr))
	    goto bail_out;

	  if (attribute_set_bignum (xf->field, "GROUP_GENERATOR_2",
				    IKE_ATTR_GROUP_GENERATOR_2, &attr))
	    goto bail_out;

	  if (attribute_set_bignum (xf->field, "GROUP_GENERATOR_2",
				    IKE_ATTR_GROUP_GENERATOR_2, &attr))
	    goto bail_out;

	  if (attribute_set_bignum (xf->field, "GROUP_CURVE_A",
				    IKE_ATTR_GROUP_CURVE_A, &attr))
	    goto bail_out;

	  if (attribute_set_bignum (xf->field, "GROUP_CURVE_B",
				    IKE_ATTR_GROUP_CURVE_B, &attr))
	    goto bail_out;
#endif
	}

      /*
       * Life durations are special, we should be able to specify
       * several, one per type.
       */
      life_conf = conf_get_list (xf->field, "Life");
      if (life_conf)
	{
	  for (life = TAILQ_FIRST (&life_conf->fields); life;
	       life = TAILQ_NEXT (life, link))
	    {
	      attribute_set_constant (life->field, "LIFE_TYPE",
				      ike_duration_cst, IKE_ATTR_LIFE_TYPE,
				      &attr);

              /* XXX Deals with 16 and 32 bit lifetimes only */
	      value = conf_get_num (life->field, "LIFE_DURATION", 0);
              if (value)
                {
	          if (value <= 0xffff)
		    attr = attribute_set_basic (attr, IKE_ATTR_LIFE_DURATION,
						value);
                  else
                    {
                      value = htonl (value);
		      attr = attribute_set_var (attr, IKE_ATTR_LIFE_DURATION,
                                                (char *)&value, sizeof value);
                    }
                }
	    }
	  conf_free_list (life_conf);
	}

      attribute_set_constant (xf->field, "PRF", ike_prf_cst, IKE_ATTR_PRF,
			      &attr);

      value = conf_get_num (xf->field, "KEY_LENGTH", 0);
      if (value)
	attr = attribute_set_basic (attr, IKE_ATTR_KEY_LENGTH, value);

      value = conf_get_num (xf->field, "FIELD_SIZE", 0);
      if (value)
	attr = attribute_set_basic (attr, IKE_ATTR_FIELD_SIZE, value);

      value = conf_get_num (xf->field, "GROUP_ORDER", 0);
      if (value)
	attr = attribute_set_basic (attr, IKE_ATTR_GROUP_ORDER, value);

      /* Record the real transform size.  */
      transforms_len += transform_len[i] = attr - transform[i];

      /* XXX I don't like exchange-specific stuff in here.  */
      if (exchange->type == ISAKMP_EXCH_AGGRESSIVE)
	{
	  /*
	   * Make sure that if a group description is specified, it is
	   * specified for all transforms equally.
	   */
	  attr = conf_get_str (xf->field, "GROUP_DESCRIPTION");
	  new_group_desc
	    = attr ? constant_value (ike_group_desc_cst, attr) : 0;
	  if (group_desc == -1)
	    group_desc = new_group_desc;
	  else if (group_desc != new_group_desc)
	    {
	      log_print ("ike_phase_1_inititor_send_SA: "
			 "differing group descriptions in a proposal");
	      goto bail_out;
	    }
	}

      /* We need to check that we actually support our configuration.  */
      if (attribute_map (transform[i] + ISAKMP_TRANSFORM_SA_ATTRS_OFF,
			 transform_len[i] - ISAKMP_TRANSFORM_SA_ATTRS_OFF,
			 exchange->doi->is_attribute_incompatible, msg))
	{
	  log_print ("ike_phase_1_initiator_send_SA: "
		     "section [%s] has unsupported attribute(s)",
		     xf->field);
	  goto bail_out;
	}
    }

  /* XXX I don't like exchange-specific stuff in here.  */
  if (exchange->type == ISAKMP_EXCH_AGGRESSIVE)
    ie->group = group_get (group_desc);

  proposal_len = ISAKMP_PROP_SPI_OFF;
  proposal = malloc (proposal_len);
  if (!proposal)
    {
      log_error ("ike_phase_1_initiator_send_SA: malloc (%lu) failed",
		 (unsigned long)proposal_len);
      goto bail_out;
    }

  SET_ISAKMP_PROP_NO (proposal, 1);
  SET_ISAKMP_PROP_PROTO (proposal, ISAKMP_PROTO_ISAKMP);
  SET_ISAKMP_PROP_SPI_SZ (proposal, 0);
  SET_ISAKMP_PROP_NTRANSFORMS (proposal, conf->cnt);

  /* XXX I would like to see this factored out.  */
  proto = calloc (1, sizeof *proto);
  if (!proto)
    {
      log_error ("ike_phase_1_initiator_send_SA: calloc (1, %lu) failed",
		 (unsigned long)sizeof *proto);
      goto bail_out;
    }

  proto->no = 1;
  proto->proto = ISAKMP_PROTO_ISAKMP;
  proto->sa = TAILQ_FIRST (&exchange->sa_list);
  TAILQ_INSERT_TAIL (&TAILQ_FIRST (&exchange->sa_list)->protos, proto,
		     link);

  sa_len = ISAKMP_SA_SIT_OFF + IPSEC_SIT_SIT_LEN;
  sa_buf = malloc (sa_len);
  if (!sa_buf)
    {
      log_error ("ike_phase_1_initiator_send_SA: malloc (%lu) failed",
	(unsigned long)sa_len);
      goto bail_out;
    }

  SET_ISAKMP_SA_DOI (sa_buf, IPSEC_DOI_IPSEC);
  SET_IPSEC_SIT_SIT (sa_buf + ISAKMP_SA_SIT_OFF, IPSEC_SIT_IDENTITY_ONLY);

  /*
   * Add the payloads.  As this is a SA, we need to recompute the
   * lengths of the payloads containing others.
   */
  if (message_add_payload (msg, ISAKMP_PAYLOAD_SA, sa_buf, sa_len, 1))
    goto bail_out;
  SET_ISAKMP_GEN_LENGTH (sa_buf,
			 sa_len + proposal_len + transforms_len);
  sa_buf = 0;

  saved_nextp = msg->nextp;
  if (message_add_payload (msg, ISAKMP_PAYLOAD_PROPOSAL, proposal,
			   proposal_len, 0))
    goto bail_out;
  SET_ISAKMP_GEN_LENGTH (proposal, proposal_len + transforms_len);
  proposal = 0;

  update_nextp = 0;
  for (i = 0; i < conf->cnt; i++)
    {
      if (message_add_payload (msg, ISAKMP_PAYLOAD_TRANSFORM, transform[i],
			       transform_len[i], update_nextp))
	goto bail_out;
      update_nextp = 1;
      transform[i] = 0;
    }
  msg->nextp = saved_nextp;

  /* Save SA payload body in ie->sa_i_b, length ie->sa_i_b_len.  */
  ie->sa_i_b_len = sa_len + proposal_len + transforms_len - ISAKMP_GEN_SZ;
  ie->sa_i_b = malloc (ie->sa_i_b_len);
  if (!ie->sa_i_b)
    {
      log_error ("ike_phase_1_initiator_send_SA: malloc (%lu) failed",
		 (unsigned long)ie->sa_i_b_len);
      goto bail_out;
    }
  memcpy (ie->sa_i_b,
	  TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_SA])->p + ISAKMP_GEN_SZ,
	  sa_len - ISAKMP_GEN_SZ);
  memcpy (ie->sa_i_b + sa_len - ISAKMP_GEN_SZ,
	  TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_PROPOSAL])->p,
	  proposal_len);
  transforms_len = 0;
  for (i = 0, p = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_TRANSFORM]);
       i < conf->cnt; i++, p = TAILQ_NEXT (p, link))
    {
      memcpy (ie->sa_i_b + sa_len + proposal_len + transforms_len
	      - ISAKMP_GEN_SZ,
	      p->p, transform_len[i]);
      transforms_len += transform_len[i];
    }

  conf_free_list (conf);
  free (transform);
  free (transform_len);
  return 0;

 bail_out:
  if (sa_buf)
    free (sa_buf);
  if (proposal)
    free (proposal);
  if (transform)
    {
      for (i = 0; i < conf->cnt; i++)
	if (transform[i])
	  free (transform[i]);
      free (transform);
    }
  if (transform_len)
    free (transform_len);
  conf_free_list (conf);
  return -1;
}

/* Figure out what transform the responder chose.  */
int
ike_phase_1_initiator_recv_SA (struct message *msg)
{
  struct exchange *exchange = msg->exchange;
  struct sa *sa = TAILQ_FIRST (&exchange->sa_list);
  struct ipsec_exch *ie = exchange->data;
  struct ipsec_sa *isa = sa->data;
  struct payload *sa_p = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_SA]);
  struct payload *prop = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_PROPOSAL]);
  struct payload *xf = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_TRANSFORM]);

  /*
   * IKE requires that only one SA with only one proposal exists and since
   * we are getting an answer on our transform offer, only one transform.
   */
  if (TAILQ_NEXT (sa_p, link) || TAILQ_NEXT (prop, link)
      || TAILQ_NEXT (xf, link))
    {
      log_print ("ike_phase_1_initiator_recv_SA: "
		 "multiple SA, proposal or transform payloads in phase 1");
      /* XXX Is there a better notification type?  */
      message_drop (msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
      return -1;
    }

  /* Check that the chosen transform matches an offer.  */
  if (message_negotiate_sa (msg, ike_phase_1_validate_prop)
      || !TAILQ_FIRST (&sa->protos))
    return -1;

  ipsec_decode_transform (msg, sa, TAILQ_FIRST (&sa->protos), xf->p);

  /* XXX I don't like exchange-specific stuff in here.  */
  if (exchange->type != ISAKMP_EXCH_AGGRESSIVE)
    ie->group = group_get (isa->group_desc);

  /* Mark the SA as handled.  */
  sa_p->flags |= PL_MARK;

  return 0;
}

/* Send our public DH value and a nonce to the responder.  */
int
ike_phase_1_initiator_send_KE_NONCE (struct message *msg)
{
  struct ipsec_exch *ie = msg->exchange->data;

  ie->g_x_len = dh_getlen (ie->group);

  /* XXX I want a better way to specify the nonce's size.  */
  return ike_phase_1_send_KE_NONCE (msg, 16);
}

/* Accept responder's public DH value and nonce.  */
int
ike_phase_1_initiator_recv_KE_NONCE (struct message *msg)
{
  if (ike_phase_1_recv_KE_NONCE (msg))
    return -1;

  return ike_phase_1_post_exchange_KE_NONCE (msg);
}

/*
 * Accept a set of transforms offered by the initiator and chose one we can
 * handle.
 */
int
ike_phase_1_responder_recv_SA (struct message *msg)
{
  struct exchange *exchange = msg->exchange;
  struct sa *sa = TAILQ_FIRST (&exchange->sa_list);
  struct ipsec_sa *isa = sa->data;
  struct payload *sa_p = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_SA]);
  struct payload *prop = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_PROPOSAL]);
  struct ipsec_exch *ie = exchange->data;

  /* Mark the SA as handled.  */
  sa_p->flags |= PL_MARK;

  /* IKE requires that only one SA with only one proposal exists.  */
  if (TAILQ_NEXT (sa_p, link) || TAILQ_NEXT (prop, link))
    {
      log_print ("ike_phase_1_responder_recv_SA: "
		 "multiple SA or proposal payloads in phase 1");
      /* XXX Is there a better notification type?  */
      message_drop (msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
      return -1;
    }

  /* Chose a transform from the SA.  */
  if (message_negotiate_sa (msg, ike_phase_1_validate_prop)
      || !TAILQ_FIRST (&sa->protos))
    return -1;

  /* XXX Move into message_negotiate_sa?  */
  ipsec_decode_transform (msg, sa, TAILQ_FIRST (&sa->protos),
			  TAILQ_FIRST (&sa->protos)->chosen->p);

  ie->group = group_get (isa->group_desc);

  /*
   * Check that the mandatory attributes: encryption, hash, authentication
   * method and Diffie-Hellman group description, has been supplied.
   */
  if (!exchange->crypto || !ie->hash || !ie->ike_auth || !ie->group)
    {
      message_drop (msg, ISAKMP_NOTIFY_PAYLOAD_MALFORMED, 0, 1, 0);
      return -1;
    }

  /* Save the body for later hash computation.  */
  ie->sa_i_b_len = GET_ISAKMP_GEN_LENGTH (sa_p->p) - ISAKMP_GEN_SZ;
  ie->sa_i_b = malloc (ie->sa_i_b_len);
  if (!ie->sa_i_b)
    {
      /* XXX How to notify peer?  */
      log_error ("ike_phase_1_responder_recv_SA: malloc (%lu) failed",
		 (unsigned long)ie->sa_i_b_len);
      return -1;
    }
  memcpy (ie->sa_i_b, sa_p->p + ISAKMP_GEN_SZ, ie->sa_i_b_len);

  return 0;
}

/* Reply with the transform we chose.  */
int
ike_phase_1_responder_send_SA (struct message *msg)
{
  /* Add the SA payload with the transform that was chosen.  */
  return message_add_sa_payload (msg);
}

/* Send our public DH value and a nonce to the peer.  */
int
ike_phase_1_send_KE_NONCE (struct message *msg, size_t nonce_sz)
{
  /* Public DH key.  */
  if (ipsec_gen_g_x (msg))
    {
      /* XXX How to log and notify peer?  */
      return -1;
    }

  /* Generate a nonce, and add it to the message.  */
  if (exchange_gen_nonce (msg, nonce_sz))
    {
      /* XXX Log?  */
      return -1;
    }

  /* Try to add certificates which are acceptable for the CERTREQs */
  if (exchange_add_certs (msg))
    {
      /* XXX Log? */
      return -1;
    }

  return 0;
}

/* Receive our peer's public DH value and nonce.  */
int
ike_phase_1_recv_KE_NONCE (struct message *msg)
{
  /* Copy out the initiator's DH public value.  */
  if (ipsec_save_g_x (msg))
    {
      /* XXX How to log and notify peer?  */
      return -1;
    }

  /* Copy out the initiator's nonce.  */
  if (exchange_save_nonce (msg))
    {
      /* XXX How to log and notify peer?  */
      return -1;
    }

  /* Copy out the initiator's cert requests.  */
  if (exchange_save_certreq (msg))
    {
      /* XXX How to log and notify peer?  */
      return -1;
    }

  return 0;
}

/*
 * Compute DH values and key material.  This is done in a post-send function
 * as that means we can do parallel work in both the initiator and responder
 * thus speeding up exchanges.
 */
int
ike_phase_1_post_exchange_KE_NONCE (struct message *msg)
{
  struct exchange *exchange = msg->exchange;
  struct ipsec_exch *ie = exchange->data;
  struct prf *prf;
  struct hash *hash = ie->hash;
  enum cryptoerr err;

  /* Compute Diffie-Hellman shared value.  */
  ie->g_xy = malloc (ie->g_x_len);
  if (!ie->g_xy)
    {
      /* XXX How to notify peer?  */
      log_error ("ike_phase_1_post_exchange_KE_NONCE: malloc (%lu) failed",
		 (unsigned long)ie->g_x_len);
      return -1;
    }
  if (dh_create_shared (ie->group, ie->g_xy,
			exchange->initiator ? ie->g_xr : ie->g_xi))
    {
      log_print ("ike_phase_1_post_exchange_KE_NONCE: "
		 "dh_create_shared failed");
      return -1;
    }
  LOG_DBG_BUF ((LOG_NEGOTIATION, 80,
		"ike_phase_1_post_exchange_KE_NONCE: g^xy", ie->g_xy,
		ie->g_x_len));

  /* Compute the SKEYID depending on the authentication method.  */
  ie->skeyid = ie->ike_auth->gen_skeyid (exchange, &ie->skeyid_len);
  if (!ie->skeyid)
    {
      /* XXX Log and teardown?  */
      return -1;
    }
  LOG_DBG_BUF ((LOG_NEGOTIATION, 80,
		"ike_phase_1_post_exchange_KE_NONCE: SKEYID", ie->skeyid,
		ie->skeyid_len));

  /* SKEYID_d.  */
  ie->skeyid_d = malloc (ie->skeyid_len);
  if (!ie->skeyid_d)
    {
      /* XXX How to notify peer?  */
      log_error ("ike_phase_1_post_exchange_KE_NONCE: malloc (%lu) failed",
		 (unsigned long)ie->skeyid_len);
      return -1;
    }
  prf = prf_alloc (ie->prf_type, hash->type, ie->skeyid, ie->skeyid_len);
  if (!prf)
    {
      /* XXX Log and teardown?  */
      return -1;
    }
  prf->Init (prf->prfctx);
  prf->Update (prf->prfctx, ie->g_xy, ie->g_x_len);
  prf->Update (prf->prfctx, exchange->cookies, ISAKMP_HDR_COOKIES_LEN);
  prf->Update (prf->prfctx, "\0", 1);
  prf->Final (ie->skeyid_d, prf->prfctx);
  LOG_DBG_BUF ((LOG_NEGOTIATION, 80,
		"ike_phase_1_post_exchange_KE_NONCE: SKEYID_d",	ie->skeyid_d,
		ie->skeyid_len));

  /* SKEYID_a.  */
  ie->skeyid_a = malloc (ie->skeyid_len);
  if (!ie->skeyid_a)
    {
      log_error ("ike_phase_1_post_exchange_KE_NONCE: malloc (%lu) failed",
		 (unsigned long)ie->skeyid_len);
      prf_free (prf);
      return -1;
    }
  prf->Init (prf->prfctx);
  prf->Update (prf->prfctx, ie->skeyid_d, ie->skeyid_len);
  prf->Update (prf->prfctx, ie->g_xy, ie->g_x_len);
  prf->Update (prf->prfctx, exchange->cookies, ISAKMP_HDR_COOKIES_LEN);
  prf->Update (prf->prfctx, "\1", 1);
  prf->Final (ie->skeyid_a, prf->prfctx);
  LOG_DBG_BUF ((LOG_NEGOTIATION, 80,
		"ike_phase_1_post_exchange_KE_NONCE: SKEYID_a",	ie->skeyid_a,
		ie->skeyid_len));

  /* SKEYID_e.  */
  ie->skeyid_e = malloc (ie->skeyid_len);
  if (!ie->skeyid_e)
    {
      /* XXX How to notify peer?  */
      log_error ("ike_phase_1_post_exchange_KE_NONCE: malloc (%lu) failed",
		 (unsigned long)ie->skeyid_len);
      prf_free (prf);
      return -1;
    }
  prf->Init (prf->prfctx);
  prf->Update (prf->prfctx, ie->skeyid_a, ie->skeyid_len);
  prf->Update (prf->prfctx, ie->g_xy, ie->g_x_len);
  prf->Update (prf->prfctx, exchange->cookies, ISAKMP_HDR_COOKIES_LEN);
  prf->Update (prf->prfctx, "\2", 1);
  prf->Final (ie->skeyid_e, prf->prfctx);
  prf_free (prf);
  LOG_DBG_BUF ((LOG_NEGOTIATION, 80,
		"ike_phase_1_post_exchange_KE_NONCE: SKEYID_e",	ie->skeyid_e,
		ie->skeyid_len));

  /* Key length determination.  */
  if (!exchange->key_length)
    exchange->key_length = exchange->crypto->keymax;

  /* Derive a longer key from skeyid_e */
  if (ie->skeyid_len < exchange->key_length)
    {
      u_int16_t len, keylen;
      u_int8_t *key, *p;

      prf = prf_alloc (ie->prf_type, hash->type, ie->skeyid_e, ie->skeyid_len);
      if (!prf)
	{
	  /* XXX - notify peer */
	  return -1;
	}

      /* Make keylen a multiple of prf->blocksize */
      keylen = exchange->key_length;
      if (keylen % prf->blocksize)
	keylen += prf->blocksize - (keylen % prf->blocksize);

      key = malloc (keylen);
      if (!key)
	{
	  /* XXX - Notify peer.  */
	  log_error ("ike_phase_1_post_exchange_KE_NONCE: malloc (%d) failed",
		     keylen);
	  return -1;
	}

      prf->Init (prf->prfctx);
      prf->Update (prf->prfctx, "\0", 1);
      prf->Final (key, prf->prfctx);

      for (len = prf->blocksize, p = key; len < exchange->key_length;
	   len += prf->blocksize, p += prf->blocksize)
	{
	  prf->Init (prf->prfctx);
	  prf->Update (prf->prfctx, p, prf->blocksize);
	  prf->Final (p + prf->blocksize, prf->prfctx);
	}
      prf_free (prf);

      /* Setup our keystate using the derived encryption key.  */
      exchange->keystate
	= crypto_init (exchange->crypto, key, exchange->key_length, &err);

      free (key);
    }
  else
    /* Setup our keystate using the raw skeyid_e.  */
    exchange->keystate = crypto_init (exchange->crypto, ie->skeyid_e,
				      exchange->key_length, &err);

  /* Special handling for DES weak keys.  */
  if (!exchange->keystate && err == EWEAKKEY
      && (exchange->key_length << 1) <= ie->skeyid_len)
    {
      log_print ("ike_phase_1_post_exchange_KE_NONCE: "
		 "weak key, trying subseq. skeyid_e");
      exchange->keystate
	= crypto_init (exchange->crypto, ie->skeyid_e + exchange->key_length,
		       exchange->key_length, &err);
    }

  if (!exchange->keystate)
    {
      log_print ("ike_phase_1_post_exchange_KE_NONCE: "
		 "exchange->crypto->init () failed: %d", err);

      /*
       * XXX We really need to know if problems are of transient nature
       * or fatal (like failed assertions etc.)
       */
      return -1;
    }

  /* Setup IV.  XXX Only for CBC transforms, no?  */
  hash->Init (hash->ctx);
  hash->Update (hash->ctx, ie->g_xi, ie->g_x_len);
  hash->Update (hash->ctx, ie->g_xr, ie->g_x_len);
  hash->Final (hash->digest, hash->ctx);
  crypto_init_iv (exchange->keystate, hash->digest,
		  exchange->crypto->blocksize);

  return 0;
}

int
ike_phase_1_responder_send_ID_AUTH (struct message *msg)
{
  if (ike_phase_1_send_ID (msg))
    return -1;

  return ike_phase_1_send_AUTH (msg);
}

int
ike_phase_1_send_ID (struct message *msg)
{
  struct exchange *exchange = msg->exchange;
  u_int8_t *buf;
  char header[80];
  ssize_t sz;
  struct sockaddr *src;
  int initiator = exchange->initiator;
  u_int8_t **id;
  size_t *id_len;
  char *my_id = 0;
  u_int8_t id_type;

  /* Choose the right fields to fill-in.  */
  id = initiator ? &exchange->id_i : &exchange->id_r;
  id_len = initiator ? &exchange->id_i_len : &exchange->id_r_len;

  if (exchange->name)
    my_id = conf_get_str (exchange->name, "ID");

  if (!my_id)
    my_id = conf_get_str ("General", "Default-phase-1-ID");

  msg->transport->vtbl->get_src (msg->transport, &src);
  sz = my_id ? ipsec_id_size (my_id, &id_type) : sockaddr_addrlen (src);
  if (sz == -1)
    return -1;

  sz += ISAKMP_ID_DATA_OFF;
  buf = malloc (sz);
  if (!buf)
    {
      log_error ("ike_phase_1_send_ID: malloc (%lu) failed",
		 (unsigned long)sz);
      return -1;
    }

  SET_IPSEC_ID_PROTO (buf + ISAKMP_ID_DOI_DATA_OFF, 0);
  SET_IPSEC_ID_PORT (buf + ISAKMP_ID_DOI_DATA_OFF, 0);
  if (my_id)
    {
      SET_ISAKMP_ID_TYPE (buf, id_type);
      switch (id_type)
	{
	case IPSEC_ID_IPV4_ADDR:
	case IPSEC_ID_IPV6_ADDR:
      	  /* Already in network byteorder.  */
      	  memcpy (buf + ISAKMP_ID_DATA_OFF, sockaddr_addrdata (src),
		  sockaddr_addrlen (src));
	  break;

	case IPSEC_ID_FQDN:
	case IPSEC_ID_USER_FQDN:
	case IPSEC_ID_KEY_ID:
	  memcpy (buf + ISAKMP_ID_DATA_OFF, conf_get_str (my_id, "Name"),
		  sz - ISAKMP_ID_DATA_OFF);
	  break;

	default:
	  log_print ("ike_phase_1_send_ID: unsupported ID type %d", id_type);
	  free (buf);
	  return -1;
	}
    }
  else
    {
      switch (src->sa_family)
	{
	case AF_INET:
	  SET_ISAKMP_ID_TYPE (buf, IPSEC_ID_IPV4_ADDR);
	  break;
	case AF_INET6:
	  SET_ISAKMP_ID_TYPE (buf, IPSEC_ID_IPV6_ADDR);
	  break;
	}
      /* Already in network byteorder.  */
      memcpy (buf + ISAKMP_ID_DATA_OFF, sockaddr_addrdata (src),
	      sockaddr_addrlen (src));
    }

  if (message_add_payload (msg, ISAKMP_PAYLOAD_ID, buf, sz, 1))
    {
      free (buf);
      return -1;
    }
  *id_len = sz - ISAKMP_GEN_SZ;
  *id = malloc (*id_len);
  if (!*id)
    {
      log_error ("ike_phase_1_send_ID: malloc (%lu) failed",
		 (unsigned long)*id_len);
      return -1;
    }
  memcpy (*id, buf + ISAKMP_GEN_SZ, *id_len);
  snprintf (header, 80, "ike_phase_1_send_ID: %s",
	    constant_name (ipsec_id_cst, GET_ISAKMP_ID_TYPE (buf)));
  LOG_DBG_BUF ((LOG_NEGOTIATION, 40, header, buf + ISAKMP_ID_DATA_OFF,
		sz - ISAKMP_ID_DATA_OFF));

  return 0;
}

int
ike_phase_1_send_AUTH (struct message *msg)
{
  struct exchange *exchange = msg->exchange;
  struct ipsec_exch *ie = exchange->data;

  if (ie->ike_auth->encode_hash (msg))
    {
      /* XXX Log? */
      return -1;
    }

  /*
   * XXX Many people say the COMMIT flag is just junk, especially in Phase 1.
   */
#ifdef notyet
  if ((exchange->flags & EXCHANGE_FLAG_COMMITTED) == 0)
    exchange->flags |= EXCHANGE_FLAG_I_COMMITTED;
#endif

  return 0;
}

/* Receive ID and HASH and check that the exchange has been consistent.  */
int
ike_phase_1_recv_ID_AUTH (struct message *msg)
{
  if (ike_phase_1_recv_ID (msg))
    return -1;

  return ike_phase_1_recv_AUTH (msg);
}

/* Receive ID.  */
int
ike_phase_1_recv_ID (struct message *msg)
{
  struct exchange *exchange = msg->exchange;
  struct payload *payload;
  char header[80], *rs = 0, *rid = 0, *p;
  int initiator = exchange->initiator;
  u_int8_t **id, id_type;
  size_t *id_len, sz;
  struct sockaddr *sa;

  payload = TAILQ_FIRST (&msg->payload[ISAKMP_PAYLOAD_ID]);

  if (exchange->name)
    rs = conf_get_str (exchange->name, "Remote-ID");

  if (rs)
    {
      sz = ipsec_id_size (rs, &id_type);
      if (sz == -1)
	{
	  log_print ("ike_phase_1_recv_ID: could not handle specified "
		     "Remote-ID [%s]", rs);
	  return -1;
	}

      rid = malloc (sz);
      if (!rid)
	{
	  log_error ("ike_phase_1_recv_ID: malloc (%lu) failed",
		     (unsigned long)sz);
	  return -1;
	}

      switch (id_type)
	{
	case IPSEC_ID_IPV4_ADDR:
	case IPSEC_ID_IPV6_ADDR:
	  p = conf_get_str (rs, "Address");
	  if (!p)
	    {
	      log_print ("ike_phase_1_recv_ID: "
			 "failed to get Address in Remote-ID section [%s]",
			 rs);
	      free (rid);
	      return -1;
	    }

	  if (text2sockaddr (p, 0, &sa) == -1)
	    {
	      log_print ("ike_phase_1_recv_ID: failed to parse address %s", p);
	      free (rid);
	      return -1;
	    }

	  if ((id_type == IPSEC_ID_IPV4_ADDR && sa->sa_family != AF_INET)
	      || (id_type == IPSEC_ID_IPV6_ADDR && sa->sa_family != AF_INET6))
	    {
	      log_print ("ike_phase_1_recv_ID: "
			 "address %s not of expected family", p);
	      free (rid);
	      free (sa);
	      return -1;
	    }

	  memcpy (rid, sockaddr_addrdata (sa), sockaddr_addrlen (sa));
	  free (sa);
	  break;

	case IPSEC_ID_FQDN:
	case IPSEC_ID_USER_FQDN:
	case IPSEC_ID_KEY_ID:
	  p = conf_get_str (rs, "Name");
	  if (!p)
	    {
	      log_print ("ike_phase_1_recv_ID: "
			 "failed to get Name in Remote-ID section [%s]", rs);
	      free (rid);
	      return -1;
	    }

	  memcpy (rid, p, sz);
	  break;

	default:
	  log_print ("ike_phase_1_recv_ID: unsupported ID type %d", id_type);
	  free (rid);
	  return -1;
	}

      /* Compare expected/desired and received remote ID */
      if (bcmp (rid, payload->p + ISAKMP_ID_DATA_OFF, sz))
	{
	  free (rid);
	  log_print ("ike_phase_1_recv_ID: "
		     "received remote ID other than expected %s", p);
	  return -1;
	}

      free (rid);
    }

  /* Choose the right fields to fill in */
  id = initiator ? &exchange->id_r : &exchange->id_i;
  id_len = initiator ? &exchange->id_r_len : &exchange->id_i_len;

  *id_len = GET_ISAKMP_GEN_LENGTH (payload->p) - ISAKMP_GEN_SZ;
  *id = malloc (*id_len);
  if (!*id)
    {
      log_error ("ike_phase_1_recv_ID: malloc (%lu) failed",
		 (unsigned long)*id_len);
      return -1;
    }
  memcpy (*id, payload->p + ISAKMP_GEN_SZ, *id_len);
  snprintf (header, 80, "ike_phase_1_recv_ID: %s",
	    constant_name (ipsec_id_cst, GET_ISAKMP_ID_TYPE (payload->p)));
  LOG_DBG_BUF ((LOG_NEGOTIATION, 40, header, payload->p + ISAKMP_ID_DATA_OFF,
		*id_len + ISAKMP_GEN_SZ - ISAKMP_ID_DATA_OFF));
  payload->flags |= PL_MARK;

  return 0;
}

/* Receive HASH and check that the exchange has been consistent.  */
int
ike_phase_1_recv_AUTH (struct message *msg)
{
  struct exchange *exchange = msg->exchange;
  struct ipsec_exch *ie = exchange->data;
  struct prf *prf;
  struct hash *hash = ie->hash;
  char header[80];
  size_t hashsize = hash->hashsize;
  int initiator = exchange->initiator;
  u_int8_t **hash_p, *id;
  size_t id_len;

  /* Choose the right fields to fill in */
  hash_p = initiator ? &ie->hash_r : &ie->hash_i;
  id = initiator ? exchange->id_r : exchange->id_i;
  id_len = initiator ? exchange->id_r_len : exchange->id_i_len;

  /* The decoded hash will be in ie->hash_r or ie->hash_i */
  if (ie->ike_auth->decode_hash (msg))
    {
      message_drop (msg, ISAKMP_NOTIFY_INVALID_ID_INFORMATION, 0, 1, 0);
      return -1;
    }

  /* Allocate the prf and start calculating his HASH.  */
  prf = prf_alloc (ie->prf_type, hash->type, ie->skeyid, ie->skeyid_len);
  if (!prf)
    {
      /* XXX Log?  */
      return -1;
    }
  prf->Init (prf->prfctx);
  prf->Update (prf->prfctx, initiator ? ie->g_xr : ie->g_xi, ie->g_x_len);
  prf->Update (prf->prfctx, initiator ? ie->g_xi : ie->g_xr, ie->g_x_len);
  prf->Update (prf->prfctx,
	       exchange->cookies
	       + (initiator ? ISAKMP_HDR_RCOOKIE_OFF : ISAKMP_HDR_ICOOKIE_OFF),
	       ISAKMP_HDR_ICOOKIE_LEN);
  prf->Update (prf->prfctx,
	       exchange->cookies
	       + (initiator ? ISAKMP_HDR_ICOOKIE_OFF : ISAKMP_HDR_RCOOKIE_OFF),
	       ISAKMP_HDR_ICOOKIE_LEN);
  prf->Update (prf->prfctx, ie->sa_i_b, ie->sa_i_b_len);
  prf->Update (prf->prfctx, id, id_len);
  prf->Final (hash->digest, prf->prfctx);
  prf_free (prf);
  snprintf (header, 80, "ike_phase_1_recv_AUTH: computed HASH_%c",
	    initiator ? 'R' : 'I');
  LOG_DBG_BUF ((LOG_NEGOTIATION, 80, header, hash->digest, hashsize));

  /* Check that the hash we got matches the one we computed.  */
  if (memcmp (*hash_p, hash->digest, hashsize) != 0)
    {
      /* XXX Log?  */
      return -1;
    }

  return 0;
}

struct attr_node {
  LIST_ENTRY (attr_node) link;
  u_int16_t type;
};

struct validation_state {
  struct conf_list_node *xf;
  LIST_HEAD (attr_head, attr_node) attrs;
  char *life;
};

/* Validate a proposal inside SA according to EXCHANGE's policy.  */
static int
ike_phase_1_validate_prop (struct exchange *exchange, struct sa *sa,
			   struct sa *isakmp_sa)
{
  struct conf_list *conf, *tags;
  struct conf_list_node *xf, *tag;
  struct proto *proto;
  struct validation_state vs;
  struct attr_node *node, *next_node;

  /* Get the list of transforms.  */
  conf = conf_get_list (exchange->policy, "Transforms");
  if (!conf)
    return 0;

  for (xf = TAILQ_FIRST (&conf->fields); xf; xf = TAILQ_NEXT (xf, link))
    {
      for (proto = TAILQ_FIRST (&sa->protos); proto;
	   proto = TAILQ_NEXT (proto, link))
	{
	  /* Mark all attributes in our policy as unseen.  */
	  LIST_INIT (&vs.attrs);
	  vs.xf = xf;
	  vs.life = 0;
	  if (attribute_map (proto->chosen->p + ISAKMP_TRANSFORM_SA_ATTRS_OFF,
			     GET_ISAKMP_GEN_LENGTH (proto->chosen->p)
			     - ISAKMP_TRANSFORM_SA_ATTRS_OFF,
			     attribute_unacceptable, &vs))
	    goto try_next;

	  /* Sweep over unseen tags in this section.  */
	  tags = conf_get_tag_list (xf->field);
	  if (tags)
	    {
	      for (tag = TAILQ_FIRST (&tags->fields); tag;
		   tag = TAILQ_NEXT (tag, link))
		/*
		 * XXX Should we care about attributes we have, they do not
		 * provide?
		 */
		for (node = LIST_FIRST (&vs.attrs); node;
		     node = next_node)
		  {
		    next_node = LIST_NEXT (node, link);
		    if (node->type
			== constant_value (ike_attr_cst, tag->field))
		      {
			LIST_REMOVE (node, link);
			free (node);
		      }
		  }
	      conf_free_list (tags);
	    }

	  /* Are there leftover tags in this section?  */
	  node = LIST_FIRST (&vs.attrs);
	  if (node)
	    goto try_next;
	}

      /* All protocols were OK, we succeeded.  */
      LOG_DBG ((LOG_NEGOTIATION, 20, "ike_phase_1_validate_prop: success"));
      conf_free_list (conf);
      if (vs.life)
	free (vs.life);
      return 1;

    try_next:
      /* Are there leftover tags in this section?  */
      node = LIST_FIRST (&vs.attrs);
      while (node)
	{
	  LIST_REMOVE (node, link);
	  free (node);
	  node = LIST_FIRST (&vs.attrs);
	}
      if (vs.life)
	free (vs.life);
    }

  LOG_DBG ((LOG_NEGOTIATION, 20, "ike_phase_1_validate_prop: failure"));
  conf_free_list (conf);
  return 0;
}

/*
 * Look at the attribute of type TYPE, located at VALUE for LEN bytes forward.
 * The VVS argument holds a validation state kept across invocations.
 * If the attribute is unacceptable to use, return non-zero, otherwise zero.
 */
static int
attribute_unacceptable (u_int16_t type, u_int8_t *value, u_int16_t len,
			void *vvs)
{
  struct validation_state *vs = vvs;
  struct conf_list *life_conf;
  struct conf_list_node *xf = vs->xf, *life;
  char *tag = constant_lookup (ike_attr_cst, type);
  char *str;
  struct constant_map *map;
  struct attr_node *node;
  int rv;

  if (!tag)
    {
      LOG_DBG ((LOG_NEGOTIATION, 60,
		"attribute_unacceptable: attribute type %d not known", type));
      return 1;
    }

  switch (type)
    {
    case IKE_ATTR_ENCRYPTION_ALGORITHM:
    case IKE_ATTR_HASH_ALGORITHM:
    case IKE_ATTR_AUTHENTICATION_METHOD:
    case IKE_ATTR_GROUP_DESCRIPTION:
    case IKE_ATTR_GROUP_TYPE:
    case IKE_ATTR_PRF:
      str = conf_get_str (xf->field, tag);
      if (!str)
	{
	  /* This attribute does not exist in this policy.  */
	  LOG_DBG ((LOG_NEGOTIATION, 70,
		    "attribute_unacceptable: attr %s does not exist in %s",
		    tag, xf->field));
	  return 1;
	}

      map = constant_link_lookup (ike_attr_cst, type);
      if (!map)
	return 1;

      if ((constant_value (map, str) == decode_16 (value)) ||
	  (!strcmp (str, "ANY")))
	{
	  /* Mark this attribute as seen.  */
	  node = malloc (sizeof *node);
	  if (!node)
	    {
	      log_error ("attribute_unacceptable: malloc (%lu) failed",
			 (unsigned long)sizeof *node);
	      return 1;
	    }
	  node->type = type;
	  LIST_INSERT_HEAD (&vs->attrs, node, link);
	  return 0;
	}
      LOG_DBG ((LOG_NEGOTIATION, 70,
		"attribute_unacceptable: %s: got %s, expected %s", tag,
		constant_lookup (map, decode_16 (value)), str));
      return 1;

    case IKE_ATTR_GROUP_PRIME:
    case IKE_ATTR_GROUP_GENERATOR_1:
    case IKE_ATTR_GROUP_GENERATOR_2:
    case IKE_ATTR_GROUP_CURVE_A:
    case IKE_ATTR_GROUP_CURVE_B:
      /* XXX Bignums not handled yet.  */
      return 1;

    case IKE_ATTR_LIFE_TYPE:
    case IKE_ATTR_LIFE_DURATION:
      life_conf = conf_get_list (xf->field, "Life");
      if (life_conf && !strcmp (conf_get_str (xf->field, "Life"), "ANY"))
	return 0;

      rv = 1;
      if (!life_conf)
	{
	  /* Life attributes given, but not in our policy.  */
	  LOG_DBG ((LOG_NEGOTIATION, 70, "attribute_unacceptable: "
		    "received unexpected life attribute"));
	  return 1;
	}

      /*
       * Each lifetime type must match, otherwise we turn the proposal down.
       * In order to do this we need to find the specific section of our
       * policy's "Life" list and match its duration
       */
      switch (type)
	{
	case IKE_ATTR_LIFE_TYPE:
	  for (life = TAILQ_FIRST (&life_conf->fields); life;
	       life = TAILQ_NEXT (life, link))
	    {
	      str = conf_get_str (life->field, "LIFE_TYPE");
	      if (!str)
		{
		  LOG_DBG ((LOG_NEGOTIATION, 70, "attribute_unacceptable: "
			    "section [%s] has no LIFE_TYPE", life->field));
		  continue;
		}

	      /*
	       * If this is the type we are looking at, save a pointer
	       * to this section in vs->life.
	       */
	      if (constant_value (ike_duration_cst, str) == decode_16 (value))
		{
		  vs->life = strdup (life->field);
		  rv = 0;
		  goto bail_out;
		}
	    }
	  LOG_DBG ((LOG_NEGOTIATION, 70,
		    "attribute_unacceptable: unrecognized LIFE_TYPE %d",
		    decode_16 (value)));
	  vs->life = 0;
	  break;

	case IKE_ATTR_LIFE_DURATION:
	  if (!vs->life)
	    {
	      LOG_DBG ((LOG_NEGOTIATION, 70, "attribute_unacceptable: "
			"LIFE_DURATION without LIFE_TYPE"));
	      rv = 1;
	      goto bail_out;
	    }

	  if (!strcmp (conf_get_str (vs->life, "LIFE_DURATION"), "ANY"))
	    rv = 0;
	  else
	    rv = !conf_match_num (vs->life, "LIFE_DURATION",
				  len == 4 ? decode_32 (value) :
				  decode_16 (value));
	  free (vs->life);
	  vs->life = 0;
	  break;
	}

    bail_out:
      conf_free_list (life_conf);
      return rv;

    case IKE_ATTR_KEY_LENGTH:
    case IKE_ATTR_FIELD_SIZE:
    case IKE_ATTR_GROUP_ORDER:
      if (conf_match_num (xf->field, tag, decode_16 (value)))
	{
	  /* Mark this attribute as seen.  */
	  node = malloc (sizeof *node);
	  if (!node)
	    {
	      log_error ("attribute_unacceptable: malloc (%lu) failed",
			 (unsigned long)sizeof *node);
	      return 1;
	    }
	  node->type = type;
	  LIST_INSERT_HEAD (&vs->attrs, node, link);
	  return 0;
	}
      return 1;
    }
  return 1;
}