summaryrefslogtreecommitdiff
path: root/source3/libads/sasl.c
blob: ee3a693f717b66001f8bc87d413d7df52ae995d1 (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
/* 
   Unix SMB/CIFS implementation.
   ads sasl code
   Copyright (C) Andrew Tridgell 2001
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "../libcli/auth/spnego.h"
#include "auth/gensec/gensec.h"
#include "auth_generic.h"
#include "ads.h"
#include "smb_krb5.h"
#include "system/gssapi.h"
#include "lib/param/loadparm.h"

#ifdef HAVE_LDAP

static ADS_STATUS ads_sasl_ntlmssp_wrap(ADS_STRUCT *ads, uint8 *buf, uint32 len)
{
	struct gensec_security *gensec_security =
		talloc_get_type_abort(ads->ldap.wrap_private_data,
		struct gensec_security);
	NTSTATUS nt_status;
	DATA_BLOB unwrapped, wrapped;
	TALLOC_CTX *frame = talloc_stackframe();

	unwrapped = data_blob_const(buf, len);

	nt_status = gensec_wrap(gensec_security, frame, &unwrapped, &wrapped);
	if (!NT_STATUS_IS_OK(nt_status)) {
		TALLOC_FREE(frame);
		return ADS_ERROR_NT(nt_status);
	}

	if ((ads->ldap.out.size - 4) < wrapped.length) {
		return ADS_ERROR_NT(NT_STATUS_INTERNAL_ERROR);
	}

	/* copy the wrapped blob to the right location */
	memcpy(ads->ldap.out.buf + 4, wrapped.data, wrapped.length);

	/* set how many bytes must be written to the underlying socket */
	ads->ldap.out.left = 4 + wrapped.length;

	TALLOC_FREE(frame);

	return ADS_SUCCESS;
}

static ADS_STATUS ads_sasl_ntlmssp_unwrap(ADS_STRUCT *ads)
{
	struct gensec_security *gensec_security =
		talloc_get_type_abort(ads->ldap.wrap_private_data,
		struct gensec_security);
	NTSTATUS nt_status;
	DATA_BLOB unwrapped, wrapped;
	TALLOC_CTX *frame = talloc_stackframe();

	wrapped = data_blob_const(ads->ldap.in.buf + 4, ads->ldap.in.ofs - 4);

	nt_status = gensec_unwrap(gensec_security, frame, &wrapped, &unwrapped);
	if (!NT_STATUS_IS_OK(nt_status)) {
		TALLOC_FREE(frame);
		return ADS_ERROR_NT(nt_status);
	}

	if (wrapped.length < unwrapped.length) {
		TALLOC_FREE(frame);
		return ADS_ERROR_NT(NT_STATUS_INTERNAL_ERROR);
	}

	/* copy the wrapped blob to the right location */
	memcpy(ads->ldap.in.buf + 4, unwrapped.data, unwrapped.length);

	/* set how many bytes must be written to the underlying socket */
	ads->ldap.in.left	= unwrapped.length;
	ads->ldap.in.ofs	= 4;

	TALLOC_FREE(frame);

	return ADS_SUCCESS;
}

static void ads_sasl_ntlmssp_disconnect(ADS_STRUCT *ads)
{
	struct gensec_security *gensec_security =
		talloc_get_type_abort(ads->ldap.wrap_private_data,
		struct gensec_security);

	TALLOC_FREE(gensec_security);

	ads->ldap.wrap_ops = NULL;
	ads->ldap.wrap_private_data = NULL;
}

static const struct ads_saslwrap_ops ads_sasl_ntlmssp_ops = {
	.name		= "ntlmssp",
	.wrap		= ads_sasl_ntlmssp_wrap,
	.unwrap		= ads_sasl_ntlmssp_unwrap,
	.disconnect	= ads_sasl_ntlmssp_disconnect
};

/* 
   perform a LDAP/SASL/SPNEGO/NTLMSSP bind (just how many layers can
   we fit on one socket??)
*/
static ADS_STATUS ads_sasl_spnego_ntlmssp_bind(ADS_STRUCT *ads)
{
	DATA_BLOB msg1 = data_blob_null;
	DATA_BLOB blob = data_blob_null;
	DATA_BLOB blob_in = data_blob_null;
	DATA_BLOB blob_out = data_blob_null;
	struct berval cred, *scred = NULL;
	int rc;
	NTSTATUS nt_status;
	ADS_STATUS status;
	int turn = 1;

	struct auth_generic_state *auth_generic_state;

	nt_status = auth_generic_client_prepare(NULL, &auth_generic_state);
	if (!NT_STATUS_IS_OK(nt_status)) {
		return ADS_ERROR_NT(nt_status);
	}

	if (!NT_STATUS_IS_OK(nt_status = auth_generic_set_username(auth_generic_state, ads->auth.user_name))) {
		return ADS_ERROR_NT(nt_status);
	}
	if (!NT_STATUS_IS_OK(nt_status = auth_generic_set_domain(auth_generic_state, ads->auth.realm))) {
		return ADS_ERROR_NT(nt_status);
	}
	if (!NT_STATUS_IS_OK(nt_status = auth_generic_set_password(auth_generic_state, ads->auth.password))) {
		return ADS_ERROR_NT(nt_status);
	}

	switch (ads->ldap.wrap_type) {
	case ADS_SASLWRAP_TYPE_SEAL:
		gensec_want_feature(auth_generic_state->gensec_security, GENSEC_FEATURE_SIGN);
		gensec_want_feature(auth_generic_state->gensec_security, GENSEC_FEATURE_SEAL);
		break;
	case ADS_SASLWRAP_TYPE_SIGN:
		if (ads->auth.flags & ADS_AUTH_SASL_FORCE) {
			gensec_want_feature(auth_generic_state->gensec_security, GENSEC_FEATURE_SIGN);
		} else {
			/*
			 * windows servers are broken with sign only,
			 * so we need to use seal here too
			 */
			gensec_want_feature(auth_generic_state->gensec_security, GENSEC_FEATURE_SIGN);
			gensec_want_feature(auth_generic_state->gensec_security, GENSEC_FEATURE_SEAL);
			ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SEAL;
		}
		break;
	case ADS_SASLWRAP_TYPE_PLAIN:
		break;
	}

	nt_status = auth_generic_client_start(auth_generic_state, GENSEC_OID_NTLMSSP);
	if (!NT_STATUS_IS_OK(nt_status)) {
		return ADS_ERROR_NT(nt_status);
	}

	blob_in = data_blob_null;

	do {
		nt_status = gensec_update(auth_generic_state->gensec_security,
					  talloc_tos(), NULL, blob_in, &blob_out);
		data_blob_free(&blob_in);
		if ((NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED) 
		     || NT_STATUS_IS_OK(nt_status))
		    && blob_out.length) {
			if (turn == 1) {
				const char *OIDs_ntlm[] = {OID_NTLMSSP, NULL};
				/* and wrap it in a SPNEGO wrapper */
				msg1 = spnego_gen_negTokenInit(talloc_tos(),
						OIDs_ntlm, &blob_out, NULL);
			} else {
				/* wrap it in SPNEGO */
				msg1 = spnego_gen_auth(talloc_tos(), blob_out);
			}

			data_blob_free(&blob_out);

			cred.bv_val = (char *)msg1.data;
			cred.bv_len = msg1.length;
			scred = NULL;
			rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSS-SPNEGO", &cred, NULL, NULL, &scred);
			data_blob_free(&msg1);
			if ((rc != LDAP_SASL_BIND_IN_PROGRESS) && (rc != 0)) {
				if (scred) {
					ber_bvfree(scred);
				}

				TALLOC_FREE(auth_generic_state);
				return ADS_ERROR(rc);
			}
			if (scred) {
				blob = data_blob(scred->bv_val, scred->bv_len);
				ber_bvfree(scred);
			} else {
				blob = data_blob_null;
			}

		} else {

			TALLOC_FREE(auth_generic_state);
			data_blob_free(&blob_out);
			return ADS_ERROR_NT(nt_status);
		}
		
		if ((turn == 1) && 
		    (rc == LDAP_SASL_BIND_IN_PROGRESS)) {
			DATA_BLOB tmp_blob = data_blob_null;
			/* the server might give us back two challenges */
			if (!spnego_parse_challenge(talloc_tos(), blob, &blob_in, 
						    &tmp_blob)) {

				TALLOC_FREE(auth_generic_state);
				data_blob_free(&blob);
				DEBUG(3,("Failed to parse challenges\n"));
				return ADS_ERROR_NT(NT_STATUS_INVALID_PARAMETER);
			}
			data_blob_free(&tmp_blob);
		} else if (rc == LDAP_SASL_BIND_IN_PROGRESS) {
			if (!spnego_parse_auth_response(talloc_tos(), blob, nt_status, OID_NTLMSSP, 
							&blob_in)) {

				TALLOC_FREE(auth_generic_state);
				data_blob_free(&blob);
				DEBUG(3,("Failed to parse auth response\n"));
				return ADS_ERROR_NT(NT_STATUS_INVALID_PARAMETER);
			}
		}
		data_blob_free(&blob);
		data_blob_free(&blob_out);
		turn++;
	} while (rc == LDAP_SASL_BIND_IN_PROGRESS && !NT_STATUS_IS_OK(nt_status));
	
	if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
		uint32_t sig_size = gensec_sig_size(auth_generic_state->gensec_security, 0);
		ads->ldap.out.max_unwrapped = ADS_SASL_WRAPPING_OUT_MAX_WRAPPED - sig_size;
		ads->ldap.out.sig_size = sig_size;
		ads->ldap.in.min_wrapped = ads->ldap.out.sig_size;
		ads->ldap.in.max_wrapped = ADS_SASL_WRAPPING_IN_MAX_WRAPPED;
		status = ads_setup_sasl_wrapping(ads, &ads_sasl_ntlmssp_ops, auth_generic_state->gensec_security);
		if (!ADS_ERR_OK(status)) {
			DEBUG(0, ("ads_setup_sasl_wrapping() failed: %s\n",
				ads_errstr(status)));
			TALLOC_FREE(auth_generic_state);
			return status;
		}
		/* Only keep the gensec_security element around long-term */
		talloc_steal(NULL, auth_generic_state->gensec_security);
	}
	TALLOC_FREE(auth_generic_state);

	return ADS_ERROR(rc);
}

#ifdef HAVE_KRB5
static ADS_STATUS ads_sasl_gssapi_wrap(ADS_STRUCT *ads, uint8 *buf, uint32 len)
{
	gss_ctx_id_t context_handle = (gss_ctx_id_t)ads->ldap.wrap_private_data;
	ADS_STATUS status;
	int gss_rc;
	uint32 minor_status;
	gss_buffer_desc unwrapped, wrapped;
	int conf_req_flag, conf_state;

	unwrapped.value		= buf;
	unwrapped.length	= len;

	/* for now request sign and seal */
	conf_req_flag	= (ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_SEAL);

	gss_rc = gss_wrap(&minor_status, context_handle,
			  conf_req_flag, GSS_C_QOP_DEFAULT,
			  &unwrapped, &conf_state,
			  &wrapped);
	status = ADS_ERROR_GSS(gss_rc, minor_status);
	if (!ADS_ERR_OK(status)) return status;

	if (conf_req_flag && conf_state == 0) {
		return ADS_ERROR_NT(NT_STATUS_ACCESS_DENIED);
	}

	if ((ads->ldap.out.size - 4) < wrapped.length) {
		return ADS_ERROR_NT(NT_STATUS_INTERNAL_ERROR);
	}

	/* copy the wrapped blob to the right location */
	memcpy(ads->ldap.out.buf + 4, wrapped.value, wrapped.length);

	/* set how many bytes must be written to the underlying socket */
	ads->ldap.out.left = 4 + wrapped.length;

	gss_release_buffer(&minor_status, &wrapped);

	return ADS_SUCCESS;
}

static ADS_STATUS ads_sasl_gssapi_unwrap(ADS_STRUCT *ads)
{
	gss_ctx_id_t context_handle = (gss_ctx_id_t)ads->ldap.wrap_private_data;
	ADS_STATUS status;
	int gss_rc;
	uint32 minor_status;
	gss_buffer_desc unwrapped, wrapped;
	int conf_state;

	wrapped.value	= ads->ldap.in.buf + 4;
	wrapped.length	= ads->ldap.in.ofs - 4;

	gss_rc = gss_unwrap(&minor_status, context_handle,
			    &wrapped, &unwrapped,
			    &conf_state, GSS_C_QOP_DEFAULT);
	status = ADS_ERROR_GSS(gss_rc, minor_status);
	if (!ADS_ERR_OK(status)) return status;

	if (ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_SEAL && conf_state == 0) {
		return ADS_ERROR_NT(NT_STATUS_ACCESS_DENIED);
	}

	if (wrapped.length < unwrapped.length) {
		return ADS_ERROR_NT(NT_STATUS_INTERNAL_ERROR);
	}

	/* copy the wrapped blob to the right location */
	memcpy(ads->ldap.in.buf + 4, unwrapped.value, unwrapped.length);

	/* set how many bytes must be written to the underlying socket */
	ads->ldap.in.left	= unwrapped.length;
	ads->ldap.in.ofs	= 4;

	gss_release_buffer(&minor_status, &unwrapped);

	return ADS_SUCCESS;
}

static void ads_sasl_gssapi_disconnect(ADS_STRUCT *ads)
{
	gss_ctx_id_t context_handle = (gss_ctx_id_t)ads->ldap.wrap_private_data;
	uint32 minor_status;

	gss_delete_sec_context(&minor_status, &context_handle, GSS_C_NO_BUFFER);

	ads->ldap.wrap_ops = NULL;
	ads->ldap.wrap_private_data = NULL;
}

static const struct ads_saslwrap_ops ads_sasl_gssapi_ops = {
	.name		= "gssapi",
	.wrap		= ads_sasl_gssapi_wrap,
	.unwrap		= ads_sasl_gssapi_unwrap,
	.disconnect	= ads_sasl_gssapi_disconnect
};

/* 
   perform a LDAP/SASL/SPNEGO/GSSKRB5 bind
*/
static ADS_STATUS ads_sasl_spnego_gsskrb5_bind(ADS_STRUCT *ads, const gss_name_t serv_name)
{
	ADS_STATUS status;
	bool ok;
	uint32 minor_status;
	int gss_rc, rc;
	gss_OID_desc krb5_mech_type =
	{9, discard_const_p(char, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02") };
	gss_OID mech_type = &krb5_mech_type;
	gss_OID actual_mech_type = GSS_C_NULL_OID;
	const char *spnego_mechs[] = {OID_KERBEROS5_OLD, OID_KERBEROS5, OID_NTLMSSP, NULL};
	gss_ctx_id_t context_handle = GSS_C_NO_CONTEXT;
	gss_buffer_desc input_token, output_token;
	uint32 req_flags, ret_flags;
	uint32 req_tmp, ret_tmp;
	DATA_BLOB unwrapped;
	DATA_BLOB wrapped;
	struct berval cred, *scred = NULL;

	input_token.value = NULL;
	input_token.length = 0;

	req_flags = GSS_C_MUTUAL_FLAG | GSS_C_REPLAY_FLAG;
	switch (ads->ldap.wrap_type) {
	case ADS_SASLWRAP_TYPE_SEAL:
		req_flags |= GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG;
		break;
	case ADS_SASLWRAP_TYPE_SIGN:
		req_flags |= GSS_C_INTEG_FLAG;
		break;
	case ADS_SASLWRAP_TYPE_PLAIN:
		break;
	}

	/* Note: here we explicit ask for the krb5 mech_type */
	gss_rc = gss_init_sec_context(&minor_status,
				      GSS_C_NO_CREDENTIAL,
				      &context_handle,
				      serv_name,
				      mech_type,
				      req_flags,
				      0,
				      NULL,
				      &input_token,
				      &actual_mech_type,
				      &output_token,
				      &ret_flags,
				      NULL);
	if (gss_rc && gss_rc != GSS_S_CONTINUE_NEEDED) {
		status = ADS_ERROR_GSS(gss_rc, minor_status);
		goto failed;
	}

	/*
	 * As some gssapi krb5 mech implementations
	 * automaticly add GSS_C_INTEG_FLAG and GSS_C_CONF_FLAG
	 * to req_flags internaly, it's not possible to
	 * use plain or signing only connection via
	 * the gssapi interface.
	 *
	 * Because of this we need to check it the ret_flags
	 * has more flags as req_flags and correct the value
	 * of ads->ldap.wrap_type.
	 *
	 * I ads->auth.flags has ADS_AUTH_SASL_FORCE
	 * we need to give an error.
	 */
	req_tmp = req_flags & (GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
	ret_tmp = ret_flags & (GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);

	if (req_tmp == ret_tmp) {
		/* everythings fine... */

	} else if (req_flags & GSS_C_CONF_FLAG) {
		/*
		 * here we wanted sealing but didn't got it
		 * from the gssapi library
		 */
		status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
		goto failed;

	} else if ((req_flags & GSS_C_INTEG_FLAG) &&
		   !(ret_flags & GSS_C_INTEG_FLAG)) {
		/*
		 * here we wanted siging but didn't got it
		 * from the gssapi library
		 */
		status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
		goto failed;

	} else if (ret_flags & GSS_C_CONF_FLAG) {
		/*
		 * here we didn't want sealing
		 * but the gssapi library forces it
		 * so correct the needed wrap_type if
		 * the caller didn't forced siging only
		 */
		if (ads->auth.flags & ADS_AUTH_SASL_FORCE) {
			status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
			goto failed;
		}

		ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SEAL;
		req_flags = ret_flags;

	} else if (ret_flags & GSS_C_INTEG_FLAG) {
		/*
		 * here we didn't want signing
		 * but the gssapi library forces it
		 * so correct the needed wrap_type if
		 * the caller didn't forced plain
		 */
		if (ads->auth.flags & ADS_AUTH_SASL_FORCE) {
			status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
			goto failed;
		}

		ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SIGN;
		req_flags = ret_flags;
	} else {
		/*
		 * This could (should?) not happen
		 */
		status = ADS_ERROR_NT(NT_STATUS_INTERNAL_ERROR);
		goto failed;
	
	}

	/* and wrap that in a shiny SPNEGO wrapper */
	unwrapped = data_blob_const(output_token.value, output_token.length);
	wrapped = spnego_gen_negTokenInit(talloc_tos(),
			spnego_mechs, &unwrapped, NULL);
	gss_release_buffer(&minor_status, &output_token);
	if (unwrapped.length > wrapped.length) {
		status = ADS_ERROR_NT(NT_STATUS_NO_MEMORY);
		goto failed;
	}

	cred.bv_val = (char *)wrapped.data;
	cred.bv_len = wrapped.length;

	rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSS-SPNEGO", &cred, NULL, NULL, 
			      &scred);
	data_blob_free(&wrapped);
	if (rc != LDAP_SUCCESS) {
		status = ADS_ERROR(rc);
		goto failed;
	}

	if (scred) {
		wrapped = data_blob_const(scred->bv_val, scred->bv_len);
	} else {
		wrapped = data_blob_null;
	}

	ok = spnego_parse_auth_response(talloc_tos(), wrapped, NT_STATUS_OK,
					OID_KERBEROS5_OLD,
					&unwrapped);
	if (scred) ber_bvfree(scred);
	if (!ok) {
		status = ADS_ERROR_NT(NT_STATUS_INVALID_NETWORK_RESPONSE);
		goto failed;
	}

	input_token.value	= unwrapped.data;
	input_token.length	= unwrapped.length;

	/* 
	 * As we asked for mutal authentication
	 * we need to pass the servers response
	 * to gssapi
	 */
	gss_rc = gss_init_sec_context(&minor_status,
				      GSS_C_NO_CREDENTIAL,
				      &context_handle,
				      serv_name,
				      mech_type,
				      req_flags,
				      0,
				      NULL,
				      &input_token,
				      &actual_mech_type,
				      &output_token,
				      &ret_flags,
				      NULL);
	data_blob_free(&unwrapped);
	if (gss_rc) {
		status = ADS_ERROR_GSS(gss_rc, minor_status);
		goto failed;
	}

	gss_release_buffer(&minor_status, &output_token);

	/*
	 * If we the sign and seal options
	 * doesn't match after getting the response
	 * from the server, we don't want to use the connection
	 */
	req_tmp = req_flags & (GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
	ret_tmp = ret_flags & (GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);

	if (req_tmp != ret_tmp) {
		/* everythings fine... */
		status = ADS_ERROR_NT(NT_STATUS_INVALID_NETWORK_RESPONSE);
		goto failed;
	}

	if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
		uint32 max_msg_size = ADS_SASL_WRAPPING_OUT_MAX_WRAPPED;

		gss_rc = gss_wrap_size_limit(&minor_status, context_handle,
					     (ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_SEAL),
					     GSS_C_QOP_DEFAULT,
					     max_msg_size, &ads->ldap.out.max_unwrapped);
		if (gss_rc) {
			status = ADS_ERROR_GSS(gss_rc, minor_status);
			goto failed;
		}

		ads->ldap.out.sig_size = max_msg_size - ads->ldap.out.max_unwrapped;
		ads->ldap.in.min_wrapped = 0x2C; /* taken from a capture with LDAP unbind */
		ads->ldap.in.max_wrapped = max_msg_size;
		status = ads_setup_sasl_wrapping(ads, &ads_sasl_gssapi_ops, context_handle);
		if (!ADS_ERR_OK(status)) {
			DEBUG(0, ("ads_setup_sasl_wrapping() failed: %s\n",
				ads_errstr(status)));
			goto failed;
		}
		/* make sure we don't free context_handle */
		context_handle = GSS_C_NO_CONTEXT;
	}

	status = ADS_SUCCESS;

failed:
	if (context_handle != GSS_C_NO_CONTEXT)
		gss_delete_sec_context(&minor_status, &context_handle, GSS_C_NO_BUFFER);
	return status;
}

#endif /* HAVE_KRB5 */

#ifdef HAVE_KRB5
struct ads_service_principal {
	 char *string;
#ifdef HAVE_KRB5
	 gss_name_t name;
#endif
};

static void ads_free_service_principal(struct ads_service_principal *p)
{
	SAFE_FREE(p->string);

#ifdef HAVE_KRB5
	if (p->name) {
		uint32 minor_status;
		gss_release_name(&minor_status, &p->name);
	}
#endif
	ZERO_STRUCTP(p);
}


static ADS_STATUS ads_guess_service_principal(ADS_STRUCT *ads,
					      char **returned_principal)
{
	char *princ = NULL;

	if (ads->server.realm && ads->server.ldap_server) {
		char *server, *server_realm;

		server = SMB_STRDUP(ads->server.ldap_server);
		server_realm = SMB_STRDUP(ads->server.realm);

		if (!server || !server_realm) {
			SAFE_FREE(server);
			SAFE_FREE(server_realm);
			return ADS_ERROR(LDAP_NO_MEMORY);
		}

		strlower_m(server);
		strupper_m(server_realm);
		if (asprintf(&princ, "ldap/%s@%s", server, server_realm) == -1) {
			SAFE_FREE(server);
			SAFE_FREE(server_realm);
			return ADS_ERROR(LDAP_NO_MEMORY);
		}

		SAFE_FREE(server);
		SAFE_FREE(server_realm);

		if (!princ) {
			return ADS_ERROR(LDAP_NO_MEMORY);
		}
	} else if (ads->config.realm && ads->config.ldap_server_name) {
		char *server, *server_realm;

		server = SMB_STRDUP(ads->config.ldap_server_name);
		server_realm = SMB_STRDUP(ads->config.realm);

		if (!server || !server_realm) {
			SAFE_FREE(server);
			SAFE_FREE(server_realm);
			return ADS_ERROR(LDAP_NO_MEMORY);
		}

		strlower_m(server);
		strupper_m(server_realm);
		if (asprintf(&princ, "ldap/%s@%s", server, server_realm) == -1) {
			SAFE_FREE(server);
			SAFE_FREE(server_realm);
			return ADS_ERROR(LDAP_NO_MEMORY);
		}

		SAFE_FREE(server);
		SAFE_FREE(server_realm);

		if (!princ) {
			return ADS_ERROR(LDAP_NO_MEMORY);
		}
	}

	if (!princ) {
		return ADS_ERROR(LDAP_PARAM_ERROR);
	}

	*returned_principal = princ;

	return ADS_SUCCESS;
}

static ADS_STATUS ads_generate_service_principal(ADS_STRUCT *ads,
						 const char *given_principal,
						 struct ads_service_principal *p)
{
	ADS_STATUS status;
#ifdef HAVE_KRB5
	gss_buffer_desc input_name;
	/* GSS_KRB5_NT_PRINCIPAL_NAME */
	gss_OID_desc nt_principal =
	{10, discard_const_p(char, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02\x01")};
	uint32 minor_status;
	int gss_rc;
#endif

	ZERO_STRUCTP(p);

	/* I've seen a child Windows 2000 domain not send
	   the principal name back in the first round of
	   the SASL bind reply.  So we guess based on server
	   name and realm.  --jerry  */
	/* Also try best guess when we get the w2k8 ignore principal
	   back, or when we are configured to ignore it - gd,
	   abartlet */

	if (!lp_client_use_spnego_principal() ||
	    !given_principal ||
	    strequal(given_principal, ADS_IGNORE_PRINCIPAL)) {

		status = ads_guess_service_principal(ads, &p->string);
		if (!ADS_ERR_OK(status)) {
			return status;
		}
	} else {
		p->string = SMB_STRDUP(given_principal);
		if (!p->string) {
			return ADS_ERROR(LDAP_NO_MEMORY);
		}
	}

#ifdef HAVE_KRB5
	input_name.value = p->string;
	input_name.length = strlen(p->string);

	gss_rc = gss_import_name(&minor_status, &input_name, &nt_principal, &p->name);
	if (gss_rc) {
		ads_free_service_principal(p);
		return ADS_ERROR_GSS(gss_rc, minor_status);
	}
#endif

	return ADS_SUCCESS;
}

/* 
   perform a LDAP/SASL/SPNEGO/KRB5 bind
*/
static ADS_STATUS ads_sasl_spnego_rawkrb5_bind(ADS_STRUCT *ads, const char *principal)
{
	DATA_BLOB blob = data_blob_null;
	struct berval cred, *scred = NULL;
	DATA_BLOB session_key = data_blob_null;
	int rc;

	if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
		return ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
	}

	rc = spnego_gen_krb5_negTokenInit(talloc_tos(), principal,
				     ads->auth.time_offset, &blob, &session_key, 0,
				     &ads->auth.tgs_expire);

	if (rc) {
		return ADS_ERROR_KRB5(rc);
	}

	/* now send the auth packet and we should be done */
	cred.bv_val = (char *)blob.data;
	cred.bv_len = blob.length;

	rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSS-SPNEGO", &cred, NULL, NULL, &scred);

	data_blob_free(&blob);
	data_blob_free(&session_key);
	if(scred)
		ber_bvfree(scred);

	return ADS_ERROR(rc);
}

static ADS_STATUS ads_sasl_spnego_krb5_bind(ADS_STRUCT *ads,
					    struct ads_service_principal *p)
{
#ifdef HAVE_KRB5
	/*
	 * we only use the gsskrb5 based implementation
	 * when sasl sign or seal is requested.
	 *
	 * This has the following reasons:
	 * - it's likely that the gssapi krb5 mech implementation
	 *   doesn't support to negotiate plain connections
	 * - the ads_sasl_spnego_rawkrb5_bind is more robust
	 *   against clock skew errors
	 */
	if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
		return ads_sasl_spnego_gsskrb5_bind(ads, p->name);
	}
#endif
	return ads_sasl_spnego_rawkrb5_bind(ads, p->string);
}
#endif /* HAVE_KRB5 */

/* 
   this performs a SASL/SPNEGO bind
*/
static ADS_STATUS ads_sasl_spnego_bind(ADS_STRUCT *ads)
{
	struct berval *scred=NULL;
	int rc, i;
	ADS_STATUS status;
	DATA_BLOB blob;
	char *given_principal = NULL;
	char *OIDs[ASN1_MAX_OIDS];
#ifdef HAVE_KRB5
	bool got_kerberos_mechanism = False;
#endif

	rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSS-SPNEGO", NULL, NULL, NULL, &scred);

	if (rc != LDAP_SASL_BIND_IN_PROGRESS) {
		status = ADS_ERROR(rc);
		goto failed;
	}

	blob = data_blob(scred->bv_val, scred->bv_len);

	ber_bvfree(scred);

#if 0
	file_save("sasl_spnego.dat", blob.data, blob.length);
#endif

	/* the server sent us the first part of the SPNEGO exchange in the negprot 
	   reply */
	if (!spnego_parse_negTokenInit(talloc_tos(), blob, OIDs, &given_principal, NULL) ||
			OIDs[0] == NULL) {
		data_blob_free(&blob);
		status = ADS_ERROR(LDAP_OPERATIONS_ERROR);
		goto failed;
	}
	data_blob_free(&blob);

	/* make sure the server understands kerberos */
	for (i=0;OIDs[i];i++) {
		DEBUG(3,("ads_sasl_spnego_bind: got OID=%s\n", OIDs[i]));
#ifdef HAVE_KRB5
		if (strcmp(OIDs[i], OID_KERBEROS5_OLD) == 0 ||
		    strcmp(OIDs[i], OID_KERBEROS5) == 0) {
			got_kerberos_mechanism = True;
		}
#endif
		talloc_free(OIDs[i]);
	}
	DEBUG(3,("ads_sasl_spnego_bind: got server principal name = %s\n", given_principal));

#ifdef HAVE_KRB5
	if (!(ads->auth.flags & ADS_AUTH_DISABLE_KERBEROS) &&
	    got_kerberos_mechanism) 
	{
		struct ads_service_principal p;

		status = ads_generate_service_principal(ads, given_principal, &p);
		TALLOC_FREE(given_principal);
		if (!ADS_ERR_OK(status)) {
			return status;
		}

		status = ads_sasl_spnego_krb5_bind(ads, &p);
		if (ADS_ERR_OK(status)) {
			ads_free_service_principal(&p);
			return status;
		}

		DEBUG(10,("ads_sasl_spnego_krb5_bind failed with: %s, "
			  "calling kinit\n", ads_errstr(status)));

		status = ADS_ERROR_KRB5(ads_kinit_password(ads)); 

		if (ADS_ERR_OK(status)) {
			status = ads_sasl_spnego_krb5_bind(ads, &p);
			if (!ADS_ERR_OK(status)) {
				DEBUG(0,("kinit succeeded but "
					"ads_sasl_spnego_krb5_bind failed: %s\n",
					ads_errstr(status)));
			}
		}

		ads_free_service_principal(&p);

		/* only fallback to NTLMSSP if allowed */
		if (ADS_ERR_OK(status) || 
		    !(ads->auth.flags & ADS_AUTH_ALLOW_NTLMSSP)) {
			return status;
		}
	} else
#endif
	{
		TALLOC_FREE(given_principal);
	}

	/* lets do NTLMSSP ... this has the big advantage that we don't need
	   to sync clocks, and we don't rely on special versions of the krb5 
	   library for HMAC_MD4 encryption */
	return ads_sasl_spnego_ntlmssp_bind(ads);

failed:
	return status;
}

#ifdef HAVE_KRB5
#define MAX_GSS_PASSES 3

/* this performs a SASL/gssapi bind
   we avoid using cyrus-sasl to make Samba more robust. cyrus-sasl
   is very dependent on correctly configured DNS whereas
   this routine is much less fragile
   see RFC2078 and RFC2222 for details
*/
static ADS_STATUS ads_sasl_gssapi_do_bind(ADS_STRUCT *ads, const gss_name_t serv_name)
{
	uint32 minor_status;
	gss_ctx_id_t context_handle = GSS_C_NO_CONTEXT;
	gss_OID mech_type = GSS_C_NULL_OID;
	gss_buffer_desc output_token, input_token;
	uint32 req_flags, ret_flags;
	int conf_state;
	struct berval cred;
	struct berval *scred = NULL;
	int i=0;
	int gss_rc, rc;
	uint8 *p;
	uint32 max_msg_size = ADS_SASL_WRAPPING_OUT_MAX_WRAPPED;
	uint8 wrap_type = ADS_SASLWRAP_TYPE_PLAIN;
	ADS_STATUS status;

	input_token.value = NULL;
	input_token.length = 0;

	/*
	 * Note: here we always ask the gssapi for sign and seal
	 *       as this is negotiated later after the mutal
	 *       authentication
	 */
	req_flags = GSS_C_MUTUAL_FLAG | GSS_C_REPLAY_FLAG | GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG;

	for (i=0; i < MAX_GSS_PASSES; i++) {
		gss_rc = gss_init_sec_context(&minor_status,
					  GSS_C_NO_CREDENTIAL,
					  &context_handle,
					  serv_name,
					  mech_type,
					  req_flags,
					  0,
					  NULL,
					  &input_token,
					  NULL,
					  &output_token,
					  &ret_flags,
					  NULL);
		if (scred) {
			ber_bvfree(scred);
			scred = NULL;
		}
		if (gss_rc && gss_rc != GSS_S_CONTINUE_NEEDED) {
			status = ADS_ERROR_GSS(gss_rc, minor_status);
			goto failed;
		}

		cred.bv_val = (char *)output_token.value;
		cred.bv_len = output_token.length;

		rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSSAPI", &cred, NULL, NULL, 
				      &scred);
		if (rc != LDAP_SASL_BIND_IN_PROGRESS) {
			status = ADS_ERROR(rc);
			goto failed;
		}

		if (output_token.value) {
			gss_release_buffer(&minor_status, &output_token);
		}

		if (scred) {
			input_token.value = scred->bv_val;
			input_token.length = scred->bv_len;
		} else {
			input_token.value = NULL;
			input_token.length = 0;
		}

		if (gss_rc == 0) break;
	}

	gss_rc = gss_unwrap(&minor_status,context_handle,&input_token,&output_token,
			    &conf_state,NULL);
	if (scred) {
		ber_bvfree(scred);
		scred = NULL;
	}
	if (gss_rc) {
		status = ADS_ERROR_GSS(gss_rc, minor_status);
		goto failed;
	}

	p = (uint8 *)output_token.value;

#if 0
	file_save("sasl_gssapi.dat", output_token.value, output_token.length);
#endif

	if (p) {
		wrap_type = CVAL(p,0);
		SCVAL(p,0,0);
		max_msg_size = RIVAL(p,0);
	}

	gss_release_buffer(&minor_status, &output_token);

	if (!(wrap_type & ads->ldap.wrap_type)) {
		/*
		 * the server doesn't supports the wrap
		 * type we want :-(
		 */
		DEBUG(0,("The ldap sasl wrap type doesn't match wanted[%d] server[%d]\n",
			ads->ldap.wrap_type, wrap_type));
		DEBUGADD(0,("You may want to set the 'client ldap sasl wrapping' option\n"));
		status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
		goto failed;
	}

	/* 0x58 is the minimum windows accepts */
	if (max_msg_size < 0x58) {
		max_msg_size = 0x58;
	}

	output_token.length = 4;
	output_token.value = SMB_MALLOC(output_token.length);
	if (!output_token.value) {
		output_token.length = 0;
		status = ADS_ERROR_NT(NT_STATUS_NO_MEMORY);
		goto failed;
	}
	p = (uint8 *)output_token.value;

	RSIVAL(p,0,max_msg_size);
	SCVAL(p,0,ads->ldap.wrap_type);

	/*
	 * we used to add sprintf("dn:%s", ads->config.bind_path) here.
	 * but using ads->config.bind_path is the wrong! It should be
	 * the DN of the user object!
	 *
	 * w2k3 gives an error when we send an incorrect DN, but sending nothing
	 * is ok and matches the information flow used in GSS-SPNEGO.
	 */

	gss_rc = gss_wrap(&minor_status, context_handle,0,GSS_C_QOP_DEFAULT,
			&output_token, /* used as *input* here. */
			&conf_state,
			&input_token); /* Used as *output* here. */
	if (gss_rc) {
		status = ADS_ERROR_GSS(gss_rc, minor_status);
		output_token.length = 0;
		SAFE_FREE(output_token.value);
		goto failed;
	}

	/* We've finished with output_token. */
	SAFE_FREE(output_token.value);
	output_token.length = 0;

	cred.bv_val = (char *)input_token.value;
	cred.bv_len = input_token.length;

	rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSSAPI", &cred, NULL, NULL, 
			      &scred);
	gss_release_buffer(&minor_status, &input_token);
	status = ADS_ERROR(rc);
	if (!ADS_ERR_OK(status)) {
		goto failed;
	}

	if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
		gss_rc = gss_wrap_size_limit(&minor_status, context_handle,
					     (ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_SEAL),
					     GSS_C_QOP_DEFAULT,
					     max_msg_size, &ads->ldap.out.max_unwrapped);
		if (gss_rc) {
			status = ADS_ERROR_GSS(gss_rc, minor_status);
			goto failed;
		}

		ads->ldap.out.sig_size = max_msg_size - ads->ldap.out.max_unwrapped;
		ads->ldap.in.min_wrapped = 0x2C; /* taken from a capture with LDAP unbind */
		ads->ldap.in.max_wrapped = max_msg_size;
		status = ads_setup_sasl_wrapping(ads, &ads_sasl_gssapi_ops, context_handle);
		if (!ADS_ERR_OK(status)) {
			DEBUG(0, ("ads_setup_sasl_wrapping() failed: %s\n",
				ads_errstr(status)));
			goto failed;
		}
		/* make sure we don't free context_handle */
		context_handle = GSS_C_NO_CONTEXT;
	}

failed:

	if (context_handle != GSS_C_NO_CONTEXT)
		gss_delete_sec_context(&minor_status, &context_handle, GSS_C_NO_BUFFER);

	if(scred)
		ber_bvfree(scred);
	return status;
}

static ADS_STATUS ads_sasl_gssapi_bind(ADS_STRUCT *ads)
{
	ADS_STATUS status;
	struct ads_service_principal p;

	status = ads_generate_service_principal(ads, NULL, &p);
	if (!ADS_ERR_OK(status)) {
		return status;
	}

	status = ads_sasl_gssapi_do_bind(ads, p.name);
	if (ADS_ERR_OK(status)) {
		ads_free_service_principal(&p);
		return status;
	}

	DEBUG(10,("ads_sasl_gssapi_do_bind failed with: %s, "
		  "calling kinit\n", ads_errstr(status)));

	status = ADS_ERROR_KRB5(ads_kinit_password(ads));

	if (ADS_ERR_OK(status)) {
		status = ads_sasl_gssapi_do_bind(ads, p.name);
	}

	ads_free_service_principal(&p);

	return status;
}

#endif /* HAVE_KRB5 */

/* mapping between SASL mechanisms and functions */
static struct {
	const char *name;
	ADS_STATUS (*fn)(ADS_STRUCT *);
} sasl_mechanisms[] = {
	{"GSS-SPNEGO", ads_sasl_spnego_bind},
#ifdef HAVE_KRB5
	{"GSSAPI", ads_sasl_gssapi_bind}, /* doesn't work with .NET RC1. No idea why */
#endif
	{NULL, NULL}
};

ADS_STATUS ads_sasl_bind(ADS_STRUCT *ads)
{
	const char *attrs[] = {"supportedSASLMechanisms", NULL};
	char **values;
	ADS_STATUS status;
	int i, j;
	LDAPMessage *res;

	/* get a list of supported SASL mechanisms */
	status = ads_do_search(ads, "", LDAP_SCOPE_BASE, "(objectclass=*)", attrs, &res);
	if (!ADS_ERR_OK(status)) return status;

	values = ldap_get_values(ads->ldap.ld, res, "supportedSASLMechanisms");

	if (ads->auth.flags & ADS_AUTH_SASL_SEAL) {
		ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SEAL;
	} else if (ads->auth.flags & ADS_AUTH_SASL_SIGN) {
		ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SIGN;
	} else {
		ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_PLAIN;
	}

	/* try our supported mechanisms in order */
	for (i=0;sasl_mechanisms[i].name;i++) {
		/* see if the server supports it */
		for (j=0;values && values[j];j++) {
			if (strcmp(values[j], sasl_mechanisms[i].name) == 0) {
				DEBUG(4,("Found SASL mechanism %s\n", values[j]));
retry:
				status = sasl_mechanisms[i].fn(ads);
				if (status.error_type == ENUM_ADS_ERROR_LDAP &&
				    status.err.rc == LDAP_STRONG_AUTH_REQUIRED &&
				    ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_PLAIN)
				{
					DEBUG(3,("SASL bin got LDAP_STRONG_AUTH_REQUIRED "
						 "retrying with signing enabled\n"));
					ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SIGN;
					goto retry;
				}
				ldap_value_free(values);
				ldap_msgfree(res);
				return status;
			}
		}
	}

	ldap_value_free(values);
	ldap_msgfree(res);
	return ADS_ERROR(LDAP_AUTH_METHOD_NOT_SUPPORTED);
}

#endif /* HAVE_LDAP */