summaryrefslogtreecommitdiffstats
path: root/source4/rpc_server/dcerpc_server.c
blob: e5f59d0cf946c65dcdb6638fda6a122115034931 (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
/* 
   Unix SMB/CIFS implementation.

   server side dcerpc core code

   Copyright (C) Andrew Tridgell 2003-2005
   Copyright (C) Stefan (metze) Metzmacher 2004-2005
   
   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 "librpc/gen_ndr/ndr_dcerpc.h"
#include "auth/auth.h"
#include "auth/gensec/gensec.h"
#include "lib/util/dlinklist.h"
#include "rpc_server/dcerpc_server.h"
#include "rpc_server/dcerpc_server_proto.h"
#include "librpc/rpc/dcerpc_proto.h"
#include "lib/events/events.h"
#include "smbd/service_task.h"
#include "smbd/service_stream.h"
#include "smbd/service.h"
#include "system/filesys.h"
#include "libcli/security/security.h"
#include "param/param.h"

#define SAMBA_ACCOC_GROUP 0x12345678

extern const struct dcesrv_interface dcesrv_mgmt_interface;

/*
  see if two endpoints match
*/
static bool endpoints_match(const struct dcerpc_binding *ep1,
			    const struct dcerpc_binding *ep2)
{
	if (ep1->transport != ep2->transport) {
		return false;
	}

	if (!ep1->endpoint || !ep2->endpoint) {
		return ep1->endpoint == ep2->endpoint;
	}

	if (strcasecmp(ep1->endpoint, ep2->endpoint) != 0) 
		return false;

	return true;
}

/*
  find an endpoint in the dcesrv_context
*/
static struct dcesrv_endpoint *find_endpoint(struct dcesrv_context *dce_ctx,
					     const struct dcerpc_binding *ep_description)
{
	struct dcesrv_endpoint *ep;
	for (ep=dce_ctx->endpoint_list; ep; ep=ep->next) {
		if (endpoints_match(ep->ep_description, ep_description)) {
			return ep;
		}
	}
	return NULL;
}

/*
  find a registered context_id from a bind or alter_context
*/
static struct dcesrv_connection_context *dcesrv_find_context(struct dcesrv_connection *conn, 
								   uint32_t context_id)
{
	struct dcesrv_connection_context *c;
	for (c=conn->contexts;c;c=c->next) {
		if (c->context_id == context_id) return c;
	}
	return NULL;
}

/*
  see if a uuid and if_version match to an interface
*/
static bool interface_match(const struct dcesrv_interface *if1,
							const struct dcesrv_interface *if2)
{
	return (if1->syntax_id.if_version == if2->syntax_id.if_version && 
			GUID_equal(&if1->syntax_id.uuid, &if2->syntax_id.uuid));
}

/*
  find the interface operations on an endpoint
*/
static const struct dcesrv_interface *find_interface(const struct dcesrv_endpoint *endpoint,
						     const struct dcesrv_interface *iface)
{
	struct dcesrv_if_list *ifl;
	for (ifl=endpoint->interface_list; ifl; ifl=ifl->next) {
		if (interface_match(&(ifl->iface), iface)) {
			return &(ifl->iface);
		}
	}
	return NULL;
}

/*
  see if a uuid and if_version match to an interface
*/
static bool interface_match_by_uuid(const struct dcesrv_interface *iface,
				    const struct GUID *uuid, uint32_t if_version)
{
	return (iface->syntax_id.if_version == if_version && 
			GUID_equal(&iface->syntax_id.uuid, uuid));
}

/*
  find the interface operations on an endpoint by uuid
*/
static const struct dcesrv_interface *find_interface_by_uuid(const struct dcesrv_endpoint *endpoint,
							     const struct GUID *uuid, uint32_t if_version)
{
	struct dcesrv_if_list *ifl;
	for (ifl=endpoint->interface_list; ifl; ifl=ifl->next) {
		if (interface_match_by_uuid(&(ifl->iface), uuid, if_version)) {
			return &(ifl->iface);
		}
	}
	return NULL;
}

/*
  find the earlier parts of a fragmented call awaiting reassembily
*/
static struct dcesrv_call_state *dcesrv_find_fragmented_call(struct dcesrv_connection *dce_conn, uint16_t call_id)
{
	struct dcesrv_call_state *c;
	for (c=dce_conn->incoming_fragmented_call_list;c;c=c->next) {
		if (c->pkt.call_id == call_id) {
			return c;
		}
	}
	return NULL;
}

/*
  register an interface on an endpoint
*/
_PUBLIC_ NTSTATUS dcesrv_interface_register(struct dcesrv_context *dce_ctx,
				   const char *ep_name,
				   const struct dcesrv_interface *iface,
				   const struct security_descriptor *sd)
{
	struct dcesrv_endpoint *ep;
	struct dcesrv_if_list *ifl;
	struct dcerpc_binding *binding;
	bool add_ep = false;
	NTSTATUS status;
	
	status = dcerpc_parse_binding(dce_ctx, ep_name, &binding);

	if (NT_STATUS_IS_ERR(status)) {
		DEBUG(0, ("Trouble parsing binding string '%s'\n", ep_name));
		return status;
	}

	/* check if this endpoint exists
	 */
	if ((ep=find_endpoint(dce_ctx, binding))==NULL) {
		ep = talloc(dce_ctx, struct dcesrv_endpoint);
		if (!ep) {
			return NT_STATUS_NO_MEMORY;
		}
		ZERO_STRUCTP(ep);
		ep->ep_description = talloc_reference(ep, binding);
		add_ep = true;

		/* add mgmt interface */
		ifl = talloc(dce_ctx, struct dcesrv_if_list);
		if (!ifl) {
			return NT_STATUS_NO_MEMORY;
		}

		memcpy(&(ifl->iface), &dcesrv_mgmt_interface, 
			   sizeof(struct dcesrv_interface));

		DLIST_ADD(ep->interface_list, ifl);
	}

	/* see if the interface is already registered on te endpoint */
	if (find_interface(ep, iface)!=NULL) {
		DEBUG(0,("dcesrv_interface_register: interface '%s' already registered on endpoint '%s'\n",
			iface->name, ep_name));
		return NT_STATUS_OBJECT_NAME_COLLISION;
	}

	/* talloc a new interface list element */
	ifl = talloc(dce_ctx, struct dcesrv_if_list);
	if (!ifl) {
		return NT_STATUS_NO_MEMORY;
	}

	/* copy the given interface struct to the one on the endpoints interface list */
	memcpy(&(ifl->iface),iface, sizeof(struct dcesrv_interface));

	/* if we have a security descriptor given,
	 * we should see if we can set it up on the endpoint
	 */
	if (sd != NULL) {
		/* if there's currently no security descriptor given on the endpoint
		 * we try to set it
		 */
		if (ep->sd == NULL) {
			ep->sd = security_descriptor_copy(dce_ctx, sd);
		}

		/* if now there's no security descriptor given on the endpoint
		 * something goes wrong, either we failed to copy the security descriptor
		 * or there was already one on the endpoint
		 */
		if (ep->sd != NULL) {
			DEBUG(0,("dcesrv_interface_register: interface '%s' failed to setup a security descriptor\n"
			         "                           on endpoint '%s'\n",
				iface->name, ep_name));
			if (add_ep) free(ep);
			free(ifl);
			return NT_STATUS_OBJECT_NAME_COLLISION;
		}
	}

	/* finally add the interface on the endpoint */
	DLIST_ADD(ep->interface_list, ifl);

	/* if it's a new endpoint add it to the dcesrv_context */
	if (add_ep) {
		DLIST_ADD(dce_ctx->endpoint_list, ep);
	}

	DEBUG(4,("dcesrv_interface_register: interface '%s' registered on endpoint '%s'\n",
		iface->name, ep_name));

	return NT_STATUS_OK;
}

static NTSTATUS dcesrv_inherited_session_key(struct dcesrv_connection *p,
					      DATA_BLOB *session_key)
{
	if (p->auth_state.session_info->session_key.length) {
		*session_key = p->auth_state.session_info->session_key;
		return NT_STATUS_OK;
	}
	return NT_STATUS_NO_USER_SESSION_KEY;
}

NTSTATUS dcesrv_generic_session_key(struct dcesrv_connection *p,
				    DATA_BLOB *session_key)
{
	/* this took quite a few CPU cycles to find ... */
	session_key->data = discard_const_p(uint8_t, "SystemLibraryDTC");
	session_key->length = 16;
	return NT_STATUS_OK;
}

/*
  fetch the user session key - may be default (above) or the SMB session key

  The key is always truncated to 16 bytes 
*/
_PUBLIC_ NTSTATUS dcesrv_fetch_session_key(struct dcesrv_connection *p,
				  DATA_BLOB *session_key)
{
	NTSTATUS status = p->auth_state.session_key(p, session_key);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	session_key->length = MIN(session_key->length, 16);

	return NT_STATUS_OK;
}


/*
  destroy a link to an endpoint
*/
static int dcesrv_endpoint_destructor(struct dcesrv_connection *p)
{
	while (p->contexts) {
		struct dcesrv_connection_context *c = p->contexts;

		DLIST_REMOVE(p->contexts, c);

		if (c->iface) {
			c->iface->unbind(c, c->iface);
		}
	}

	return 0;
}


/*
  connect to a dcerpc endpoint
*/
_PUBLIC_ NTSTATUS dcesrv_endpoint_connect(struct dcesrv_context *dce_ctx,
				 TALLOC_CTX *mem_ctx,
				 const struct dcesrv_endpoint *ep,
				 struct auth_session_info *session_info,
				 struct event_context *event_ctx,
				 struct messaging_context *msg_ctx,
				 struct server_id server_id,
				 uint32_t state_flags,
				 struct dcesrv_connection **_p)
{
	struct dcesrv_connection *p;

	if (!session_info) {
		return NT_STATUS_ACCESS_DENIED;
	}

	p = talloc(mem_ctx, struct dcesrv_connection);
	NT_STATUS_HAVE_NO_MEMORY(p);

	if (!talloc_reference(p, session_info)) {
		talloc_free(p);
		return NT_STATUS_NO_MEMORY;
	}

	p->dce_ctx = dce_ctx;
	p->endpoint = ep;
	p->contexts = NULL;
	p->call_list = NULL;
	p->incoming_fragmented_call_list = NULL;
	p->pending_call_list = NULL;
	p->cli_max_recv_frag = 0;
	p->partial_input = data_blob(NULL, 0);
	p->auth_state.auth_info = NULL;
	p->auth_state.gensec_security = NULL;
	p->auth_state.session_info = session_info;
	p->auth_state.session_key = dcesrv_generic_session_key;
	p->event_ctx = event_ctx;
	p->msg_ctx = msg_ctx;
	p->server_id = server_id;
	p->processing = false;
	p->state_flags = state_flags;
	ZERO_STRUCT(p->transport);

	talloc_set_destructor(p, dcesrv_endpoint_destructor);

	*_p = p;
	return NT_STATUS_OK;
}

/*
  search and connect to a dcerpc endpoint
*/
_PUBLIC_ NTSTATUS dcesrv_endpoint_search_connect(struct dcesrv_context *dce_ctx,
					TALLOC_CTX *mem_ctx,
					const struct dcerpc_binding *ep_description,
					struct auth_session_info *session_info,
					struct event_context *event_ctx,
					struct messaging_context *msg_ctx,
					struct server_id server_id,
					uint32_t state_flags,
					struct dcesrv_connection **dce_conn_p)
{
	NTSTATUS status;
	const struct dcesrv_endpoint *ep;

	/* make sure this endpoint exists */
	ep = find_endpoint(dce_ctx, ep_description);
	if (!ep) {
		return NT_STATUS_OBJECT_NAME_NOT_FOUND;
	}

	status = dcesrv_endpoint_connect(dce_ctx, mem_ctx, ep, session_info,
					 event_ctx, msg_ctx, server_id,
					 state_flags, dce_conn_p);
	NT_STATUS_NOT_OK_RETURN(status);

	(*dce_conn_p)->auth_state.session_key = dcesrv_inherited_session_key;

	/* TODO: check security descriptor of the endpoint here 
	 *       if it's a smb named pipe
	 *	 if it's failed free dce_conn_p
	 */

	return NT_STATUS_OK;
}


static void dcesrv_init_hdr(struct ncacn_packet *pkt, bool bigendian)
{
	pkt->rpc_vers = 5;
	pkt->rpc_vers_minor = 0;
	if (bigendian) {
		pkt->drep[0] = 0;
	} else {
		pkt->drep[0] = DCERPC_DREP_LE;
	}
	pkt->drep[1] = 0;
	pkt->drep[2] = 0;
	pkt->drep[3] = 0;
}

/*
  move a call from an existing linked list to the specified list. This
  prevents bugs where we forget to remove the call from a previous
  list when moving it.
 */
static void dcesrv_call_set_list(struct dcesrv_call_state *call, 
				 enum dcesrv_call_list list)
{
	switch (call->list) {
	case DCESRV_LIST_NONE:
		break;
	case DCESRV_LIST_CALL_LIST:
		DLIST_REMOVE(call->conn->call_list, call);
		break;
	case DCESRV_LIST_FRAGMENTED_CALL_LIST:
		DLIST_REMOVE(call->conn->incoming_fragmented_call_list, call);
		break;
	case DCESRV_LIST_PENDING_CALL_LIST:
		DLIST_REMOVE(call->conn->pending_call_list, call);
		break;
	}
	call->list = list;
	switch (list) {
	case DCESRV_LIST_NONE:
		break;
	case DCESRV_LIST_CALL_LIST:
		DLIST_ADD_END(call->conn->call_list, call, struct dcesrv_call_state *);
		break;
	case DCESRV_LIST_FRAGMENTED_CALL_LIST:
		DLIST_ADD_END(call->conn->incoming_fragmented_call_list, call, struct dcesrv_call_state *);
		break;
	case DCESRV_LIST_PENDING_CALL_LIST:
		DLIST_ADD_END(call->conn->pending_call_list, call, struct dcesrv_call_state *);
		break;
	}
}

/*
  return a dcerpc fault
*/
static NTSTATUS dcesrv_fault(struct dcesrv_call_state *call, uint32_t fault_code)
{
	struct ncacn_packet pkt;
	struct data_blob_list_item *rep;
	uint8_t zeros[4];
	NTSTATUS status;

	/* setup a bind_ack */
	dcesrv_init_hdr(&pkt, lp_rpc_big_endian(call->conn->dce_ctx->lp_ctx));
	pkt.auth_length = 0;
	pkt.call_id = call->pkt.call_id;
	pkt.ptype = DCERPC_PKT_FAULT;
	pkt.pfc_flags = DCERPC_PFC_FLAG_FIRST | DCERPC_PFC_FLAG_LAST;
	pkt.u.fault.alloc_hint = 0;
	pkt.u.fault.context_id = 0;
	pkt.u.fault.cancel_count = 0;
	pkt.u.fault.status = fault_code;

	ZERO_STRUCT(zeros);
	pkt.u.fault._pad = data_blob_const(zeros, sizeof(zeros));

	rep = talloc(call, struct data_blob_list_item);
	if (!rep) {
		return NT_STATUS_NO_MEMORY;
	}

	status = ncacn_push_auth(&rep->blob, call, lp_iconv_convenience(call->conn->dce_ctx->lp_ctx), &pkt, NULL);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	dcerpc_set_frag_length(&rep->blob, rep->blob.length);

	DLIST_ADD_END(call->replies, rep, struct data_blob_list_item *);
	dcesrv_call_set_list(call, DCESRV_LIST_CALL_LIST);

	return NT_STATUS_OK;	
}


/*
  return a dcerpc bind_nak
*/
static NTSTATUS dcesrv_bind_nak(struct dcesrv_call_state *call, uint32_t reason)
{
	struct ncacn_packet pkt;
	struct data_blob_list_item *rep;
	NTSTATUS status;

	/* setup a bind_nak */
	dcesrv_init_hdr(&pkt, lp_rpc_big_endian(call->conn->dce_ctx->lp_ctx));
	pkt.auth_length = 0;
	pkt.call_id = call->pkt.call_id;
	pkt.ptype = DCERPC_PKT_BIND_NAK;
	pkt.pfc_flags = DCERPC_PFC_FLAG_FIRST | DCERPC_PFC_FLAG_LAST;
	pkt.u.bind_nak.reject_reason = reason;
	if (pkt.u.bind_nak.reject_reason == DECRPC_BIND_PROTOCOL_VERSION_NOT_SUPPORTED) {
		pkt.u.bind_nak.versions.v.num_versions = 0;
	}

	rep = talloc(call, struct data_blob_list_item);
	if (!rep) {
		return NT_STATUS_NO_MEMORY;
	}

	status = ncacn_push_auth(&rep->blob, call, lp_iconv_convenience(call->conn->dce_ctx->lp_ctx), &pkt, NULL);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	dcerpc_set_frag_length(&rep->blob, rep->blob.length);

	DLIST_ADD_END(call->replies, rep, struct data_blob_list_item *);
	dcesrv_call_set_list(call, DCESRV_LIST_CALL_LIST);

	return NT_STATUS_OK;	
}


/*
  handle a bind request
*/
static NTSTATUS dcesrv_bind(struct dcesrv_call_state *call)
{
	uint32_t if_version, transfer_syntax_version;
	struct GUID uuid, *transfer_syntax_uuid;
	struct ncacn_packet pkt;
	struct data_blob_list_item *rep;
	NTSTATUS status;
	uint32_t result=0, reason=0;
	uint32_t context_id;
	const struct dcesrv_interface *iface;
	uint32_t extra_flags = 0;

	/*
	 * Association groups allow policy handles to be shared across
	 * multiple client connections.  We don't implement this yet.
	 *
	 * So we just allow 0 if the client wants to create a new
	 * association group.
	 *
	 * And we allow the 0x12345678 value, we give away as
	 * assoc_group_id back to the clients
	 */
	if (call->pkt.u.bind.assoc_group_id != 0 &&
	    call->pkt.u.bind.assoc_group_id != SAMBA_ACCOC_GROUP) {
		return dcesrv_bind_nak(call, 0);	
	}

	if (call->pkt.u.bind.num_contexts < 1 ||
	    call->pkt.u.bind.ctx_list[0].num_transfer_syntaxes < 1) {
		return dcesrv_bind_nak(call, 0);
	}

	context_id = call->pkt.u.bind.ctx_list[0].context_id;

	/* you can't bind twice on one context */
	if (dcesrv_find_context(call->conn, context_id) != NULL) {
		return dcesrv_bind_nak(call, 0);
	}

	if_version = call->pkt.u.bind.ctx_list[0].abstract_syntax.if_version;
	uuid = call->pkt.u.bind.ctx_list[0].abstract_syntax.uuid;

	transfer_syntax_version = call->pkt.u.bind.ctx_list[0].transfer_syntaxes[0].if_version;
	transfer_syntax_uuid = &call->pkt.u.bind.ctx_list[0].transfer_syntaxes[0].uuid;
	if (!GUID_equal(&ndr_transfer_syntax.uuid, transfer_syntax_uuid) != 0 ||
	    ndr_transfer_syntax.if_version != transfer_syntax_version) {
		char *uuid_str = GUID_string(call, transfer_syntax_uuid);
		/* we only do NDR encoded dcerpc */
		DEBUG(0,("Non NDR transfer syntax requested - %s\n", uuid_str));
		talloc_free(uuid_str);
		return dcesrv_bind_nak(call, 0);
	}

	iface = find_interface_by_uuid(call->conn->endpoint, &uuid, if_version);
	if (iface == NULL) {
		char *uuid_str = GUID_string(call, &uuid);
		DEBUG(2,("Request for unknown dcerpc interface %s/%d\n", uuid_str, if_version));
		talloc_free(uuid_str);

		/* we don't know about that interface */
		result = DCERPC_BIND_PROVIDER_REJECT;
		reason = DCERPC_BIND_REASON_ASYNTAX;		
	}

	if (iface) {
		/* add this context to the list of available context_ids */
		struct dcesrv_connection_context *context = talloc(call->conn, 
								   struct dcesrv_connection_context);
		if (context == NULL) {
			return dcesrv_bind_nak(call, 0);
		}
		context->conn = call->conn;
		context->iface = iface;
		context->context_id = context_id;
		context->private = NULL;
		context->handles = NULL;
		DLIST_ADD(call->conn->contexts, context);
		call->context = context;
	}

	if (call->conn->cli_max_recv_frag == 0) {
		call->conn->cli_max_recv_frag = call->pkt.u.bind.max_recv_frag;
	}

	if ((call->pkt.pfc_flags & DCERPC_PFC_FLAG_SUPPORT_HEADER_SIGN) &&
	    lp_parm_bool(call->conn->dce_ctx->lp_ctx, NULL, "dcesrv","header signing", false)) {
		call->conn->state_flags |= DCESRV_CALL_STATE_FLAG_HEADER_SIGNING;
		extra_flags |= DCERPC_PFC_FLAG_SUPPORT_HEADER_SIGN;
	}

	/* handle any authentication that is being requested */
	if (!dcesrv_auth_bind(call)) {
		return dcesrv_bind_nak(call, DCERPC_BIND_REASON_INVALID_AUTH_TYPE);
	}

	/* setup a bind_ack */
	dcesrv_init_hdr(&pkt, lp_rpc_big_endian(call->conn->dce_ctx->lp_ctx));
	pkt.auth_length = 0;
	pkt.call_id = call->pkt.call_id;
	pkt.ptype = DCERPC_PKT_BIND_ACK;
	pkt.pfc_flags = DCERPC_PFC_FLAG_FIRST | DCERPC_PFC_FLAG_LAST | extra_flags;
	pkt.u.bind_ack.max_xmit_frag = 0x2000;
	pkt.u.bind_ack.max_recv_frag = 0x2000;
	/* we need to send a non zero assoc_group_id here to make longhorn happy, it also matches samba3 */
	pkt.u.bind_ack.assoc_group_id = SAMBA_ACCOC_GROUP;
	if (iface) {
		/* FIXME: Use pipe name as specified by endpoint instead of interface name */
		pkt.u.bind_ack.secondary_address = talloc_asprintf(call, "\\PIPE\\%s", iface->name);
	} else {
		pkt.u.bind_ack.secondary_address = "";
	}
	pkt.u.bind_ack.num_results = 1;
	pkt.u.bind_ack.ctx_list = talloc(call, struct dcerpc_ack_ctx);
	if (!pkt.u.bind_ack.ctx_list) {
		return NT_STATUS_NO_MEMORY;
	}
	pkt.u.bind_ack.ctx_list[0].result = result;
	pkt.u.bind_ack.ctx_list[0].reason = reason;
	pkt.u.bind_ack.ctx_list[0].syntax = ndr_transfer_syntax;
	pkt.u.bind_ack.auth_info = data_blob(NULL, 0);

	status = dcesrv_auth_bind_ack(call, &pkt);
	if (!NT_STATUS_IS_OK(status)) {
		return dcesrv_bind_nak(call, 0);
	}

	if (iface) {
		status = iface->bind(call, iface);
		if (!NT_STATUS_IS_OK(status)) {
			char *uuid_str = GUID_string(call, &uuid);
			DEBUG(2,("Request for dcerpc interface %s/%d rejected: %s\n", 
				 uuid_str, if_version, nt_errstr(status)));
			talloc_free(uuid_str);
			return dcesrv_bind_nak(call, 0);
		}
	}

	rep = talloc(call, struct data_blob_list_item);
	if (!rep) {
		return NT_STATUS_NO_MEMORY;
	}

	status = ncacn_push_auth(&rep->blob, call, lp_iconv_convenience(call->conn->dce_ctx->lp_ctx), &pkt, call->conn->auth_state.auth_info);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	dcerpc_set_frag_length(&rep->blob, rep->blob.length);

	DLIST_ADD_END(call->replies, rep, struct data_blob_list_item *);
	dcesrv_call_set_list(call, DCESRV_LIST_CALL_LIST);

	return NT_STATUS_OK;
}


/*
  handle a auth3 request
*/
static NTSTATUS dcesrv_auth3(struct dcesrv_call_state *call)
{
	/* handle the auth3 in the auth code */
	if (!dcesrv_auth_auth3(call)) {
		return dcesrv_fault(call, DCERPC_FAULT_OTHER);
	}

	talloc_free(call);

	/* we don't send a reply to a auth3 request, except by a
	   fault */
	return NT_STATUS_OK;
}


/*
  handle a bind request
*/
static NTSTATUS dcesrv_alter_new_context(struct dcesrv_call_state *call, uint32_t context_id)
{
	uint32_t if_version, transfer_syntax_version;
	struct dcesrv_connection_context *context;
	const struct dcesrv_interface *iface;
	struct GUID uuid, *transfer_syntax_uuid;
	NTSTATUS status;

	if_version = call->pkt.u.alter.ctx_list[0].abstract_syntax.if_version;
	uuid = call->pkt.u.alter.ctx_list[0].abstract_syntax.uuid;

	transfer_syntax_version = call->pkt.u.alter.ctx_list[0].transfer_syntaxes[0].if_version;
	transfer_syntax_uuid = &call->pkt.u.alter.ctx_list[0].transfer_syntaxes[0].uuid;
	if (!GUID_equal(transfer_syntax_uuid, &ndr_transfer_syntax.uuid) ||
	    ndr_transfer_syntax.if_version != transfer_syntax_version) {
		/* we only do NDR encoded dcerpc */
		return NT_STATUS_RPC_PROTSEQ_NOT_SUPPORTED;
	}

	iface = find_interface_by_uuid(call->conn->endpoint, &uuid, if_version);
	if (iface == NULL) {
		char *uuid_str = GUID_string(call, &uuid);
		DEBUG(2,("Request for unknown dcerpc interface %s/%d\n", uuid_str, if_version));
		talloc_free(uuid_str);
		return NT_STATUS_RPC_PROTSEQ_NOT_SUPPORTED;
	}

	/* add this context to the list of available context_ids */
	context = talloc(call->conn, struct dcesrv_connection_context);
	if (context == NULL) {
		return NT_STATUS_NO_MEMORY;
	}
	context->conn = call->conn;
	context->iface = iface;
	context->context_id = context_id;
	context->private = NULL;
	context->handles = NULL;
	DLIST_ADD(call->conn->contexts, context);
	call->context = context;

	if (iface) {
		status = iface->bind(call, iface);
		if (!NT_STATUS_IS_OK(status)) {
			return status;
		}
	}

	return NT_STATUS_OK;
}


/*
  handle a alter context request
*/
static NTSTATUS dcesrv_alter(struct dcesrv_call_state *call)
{
	struct ncacn_packet pkt;
	struct data_blob_list_item *rep;
	NTSTATUS status;
	uint32_t result=0, reason=0;
	uint32_t context_id;

	/* handle any authentication that is being requested */
	if (!dcesrv_auth_alter(call)) {
		/* TODO: work out the right reject code */
		result = DCERPC_BIND_PROVIDER_REJECT;
		reason = DCERPC_BIND_REASON_ASYNTAX;		
	}

	context_id = call->pkt.u.alter.ctx_list[0].context_id;

	/* see if they are asking for a new interface */
	if (result == 0 &&
	    dcesrv_find_context(call->conn, context_id) == NULL) {
		status = dcesrv_alter_new_context(call, context_id);
		if (!NT_STATUS_IS_OK(status)) {
			result = DCERPC_BIND_PROVIDER_REJECT;
			reason = DCERPC_BIND_REASON_ASYNTAX;		
		}
	}

	/* setup a alter_resp */
	dcesrv_init_hdr(&pkt, lp_rpc_big_endian(call->conn->dce_ctx->lp_ctx));
	pkt.auth_length = 0;
	pkt.call_id = call->pkt.call_id;
	pkt.ptype = DCERPC_PKT_ALTER_RESP;
	pkt.pfc_flags = DCERPC_PFC_FLAG_FIRST | DCERPC_PFC_FLAG_LAST;
	pkt.u.alter_resp.max_xmit_frag = 0x2000;
	pkt.u.alter_resp.max_recv_frag = 0x2000;
	pkt.u.alter_resp.assoc_group_id = call->pkt.u.alter.assoc_group_id;
	pkt.u.alter_resp.num_results = 1;
	pkt.u.alter_resp.ctx_list = talloc_array(call, struct dcerpc_ack_ctx, 1);
	if (!pkt.u.alter_resp.ctx_list) {
		return NT_STATUS_NO_MEMORY;
	}
	pkt.u.alter_resp.ctx_list[0].result = result;
	pkt.u.alter_resp.ctx_list[0].reason = reason;
	pkt.u.alter_resp.ctx_list[0].syntax = ndr_transfer_syntax;
	pkt.u.alter_resp.auth_info = data_blob(NULL, 0);
	pkt.u.alter_resp.secondary_address = "";

	status = dcesrv_auth_alter_ack(call, &pkt);
	if (!NT_STATUS_IS_OK(status)) {
		if (NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)
		    || NT_STATUS_EQUAL(status, NT_STATUS_LOGON_FAILURE)
		    || NT_STATUS_EQUAL(status, NT_STATUS_NO_SUCH_USER)
		    || NT_STATUS_EQUAL(status, NT_STATUS_WRONG_PASSWORD)) {
			return dcesrv_fault(call, DCERPC_FAULT_ACCESS_DENIED);
		}
		return dcesrv_fault(call, 0);
	}

	rep = talloc(call, struct data_blob_list_item);
	if (!rep) {
		return NT_STATUS_NO_MEMORY;
	}

	status = ncacn_push_auth(&rep->blob, call, lp_iconv_convenience(call->conn->dce_ctx->lp_ctx), &pkt, call->conn->auth_state.auth_info);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	dcerpc_set_frag_length(&rep->blob, rep->blob.length);

	DLIST_ADD_END(call->replies, rep, struct data_blob_list_item *);
	dcesrv_call_set_list(call, DCESRV_LIST_CALL_LIST);

	return NT_STATUS_OK;
}

/*
  handle a dcerpc request packet
*/
static NTSTATUS dcesrv_request(struct dcesrv_call_state *call)
{
	struct ndr_pull *pull;
	NTSTATUS status;
	struct dcesrv_connection_context *context;

	/* if authenticated, and the mech we use can't do async replies, don't use them... */
	if (call->conn->auth_state.gensec_security && 
	    !gensec_have_feature(call->conn->auth_state.gensec_security, GENSEC_FEATURE_ASYNC_REPLIES)) {
		call->state_flags &= ~DCESRV_CALL_STATE_FLAG_MAY_ASYNC;
	}

	context = dcesrv_find_context(call->conn, call->pkt.u.request.context_id);
	if (context == NULL) {
		return dcesrv_fault(call, DCERPC_FAULT_UNK_IF);
	}

	pull = ndr_pull_init_blob(&call->pkt.u.request.stub_and_verifier, call,
				  lp_iconv_convenience(call->conn->dce_ctx->lp_ctx));
	NT_STATUS_HAVE_NO_MEMORY(pull);

	pull->flags |= LIBNDR_FLAG_REF_ALLOC;

	call->context	= context;
	call->ndr_pull	= pull;

	if (call->pkt.pfc_flags & DCERPC_PFC_FLAG_OBJECT_UUID) {
		pull->flags |= LIBNDR_FLAG_OBJECT_PRESENT;
	}

	if (!(call->pkt.drep[0] & DCERPC_DREP_LE)) {
		pull->flags |= LIBNDR_FLAG_BIGENDIAN;
	}

	/* unravel the NDR for the packet */
	status = context->iface->ndr_pull(call, call, pull, &call->r);
	if (!NT_STATUS_IS_OK(status)) {
		return dcesrv_fault(call, call->fault_code);
	}

	if (pull->offset != pull->data_size) {
		DEBUG(3,("Warning: %d extra bytes in incoming RPC request\n", 
			 pull->data_size - pull->offset));
		dump_data(10, pull->data+pull->offset, pull->data_size - pull->offset);
	}

	/* call the dispatch function */
	status = context->iface->dispatch(call, call, call->r);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(5,("dcerpc fault in call %s:%02x - %s\n",
			 context->iface->name, 
			 call->pkt.u.request.opnum,
			 dcerpc_errstr(pull, call->fault_code)));
		return dcesrv_fault(call, call->fault_code);
	}

	/* add the call to the pending list */
	dcesrv_call_set_list(call, DCESRV_LIST_PENDING_CALL_LIST);

	if (call->state_flags & DCESRV_CALL_STATE_FLAG_ASYNC) {
		return NT_STATUS_OK;
	}

	return dcesrv_reply(call);
}

_PUBLIC_ NTSTATUS dcesrv_reply(struct dcesrv_call_state *call)
{
	struct ndr_push *push;
	NTSTATUS status;
	DATA_BLOB stub;
	uint32_t total_length, chunk_size;
	struct dcesrv_connection_context *context = call->context;
	size_t sig_size = 0;

	/* call the reply function */
	status = context->iface->reply(call, call, call->r);
	if (!NT_STATUS_IS_OK(status)) {
		return dcesrv_fault(call, call->fault_code);
	}

	/* form the reply NDR */
	push = ndr_push_init_ctx(call, lp_iconv_convenience(call->conn->dce_ctx->lp_ctx));
	NT_STATUS_HAVE_NO_MEMORY(push);

	/* carry over the pointer count to the reply in case we are
	   using full pointer. See NDR specification for full
	   pointers */
	push->ptr_count = call->ndr_pull->ptr_count;

	if (lp_rpc_big_endian(call->conn->dce_ctx->lp_ctx)) {
		push->flags |= LIBNDR_FLAG_BIGENDIAN;
	}

	status = context->iface->ndr_push(call, call, push, call->r);
	if (!NT_STATUS_IS_OK(status)) {
		return dcesrv_fault(call, call->fault_code);
	}

	stub = ndr_push_blob(push);

	total_length = stub.length;

	/* we can write a full max_recv_frag size, minus the dcerpc
	   request header size */
	chunk_size = call->conn->cli_max_recv_frag;
	chunk_size -= DCERPC_REQUEST_LENGTH;
	if (call->conn->auth_state.auth_info &&
	    call->conn->auth_state.gensec_security) {
		sig_size = gensec_sig_size(call->conn->auth_state.gensec_security,
					   call->conn->cli_max_recv_frag);
		if (sig_size) {
			chunk_size -= DCERPC_AUTH_TRAILER_LENGTH;
			chunk_size -= sig_size;
		}
	}
	chunk_size -= (chunk_size % 16);

	do {
		uint32_t length;
		struct data_blob_list_item *rep;
		struct ncacn_packet pkt;

		rep = talloc(call, struct data_blob_list_item);
		NT_STATUS_HAVE_NO_MEMORY(rep);

		length = MIN(chunk_size, stub.length);

		/* form the dcerpc response packet */
		dcesrv_init_hdr(&pkt, lp_rpc_big_endian(call->conn->dce_ctx->lp_ctx));
		pkt.auth_length = 0;
		pkt.call_id = call->pkt.call_id;
		pkt.ptype = DCERPC_PKT_RESPONSE;
		pkt.pfc_flags = 0;
		if (stub.length == total_length) {
			pkt.pfc_flags |= DCERPC_PFC_FLAG_FIRST;
		}
		if (length == stub.length) {
			pkt.pfc_flags |= DCERPC_PFC_FLAG_LAST;
		}
		pkt.u.response.alloc_hint = stub.length;
		pkt.u.response.context_id = call->pkt.u.request.context_id;
		pkt.u.response.cancel_count = 0;
		pkt.u.response.stub_and_verifier.data = stub.data;
		pkt.u.response.stub_and_verifier.length = length;

		if (!dcesrv_auth_response(call, &rep->blob, sig_size, &pkt)) {
			return dcesrv_fault(call, DCERPC_FAULT_OTHER);		
		}

		dcerpc_set_frag_length(&rep->blob, rep->blob.length);

		DLIST_ADD_END(call->replies, rep, struct data_blob_list_item *);
		
		stub.data += length;
		stub.length -= length;
	} while (stub.length != 0);

	/* move the call from the pending to the finished calls list */
	dcesrv_call_set_list(call, DCESRV_LIST_CALL_LIST);

	if (call->conn->call_list && call->conn->call_list->replies) {
		if (call->conn->transport.report_output_data) {
			call->conn->transport.report_output_data(call->conn);
		}
	}

	return NT_STATUS_OK;
}

_PUBLIC_ struct socket_address *dcesrv_connection_get_my_addr(struct dcesrv_connection *conn, TALLOC_CTX *mem_ctx)
{
	if (!conn->transport.get_my_addr) {
		return NULL;
	}

	return conn->transport.get_my_addr(conn, mem_ctx);
}

_PUBLIC_ struct socket_address *dcesrv_connection_get_peer_addr(struct dcesrv_connection *conn, TALLOC_CTX *mem_ctx)
{
	if (!conn->transport.get_peer_addr) {
		return NULL;
	}

	return conn->transport.get_peer_addr(conn, mem_ctx);
}

/*
  work out if we have a full packet yet
*/
static bool dce_full_packet(const DATA_BLOB *data)
{
	if (data->length < DCERPC_FRAG_LEN_OFFSET+2) {
		return false;
	}
	if (dcerpc_get_frag_length(data) > data->length) {
		return false;
	}
	return true;
}

/*
  we might have consumed only part of our input - advance past that part
*/
static void dce_partial_advance(struct dcesrv_connection *dce_conn, uint32_t offset)
{
	DATA_BLOB blob;

	if (dce_conn->partial_input.length == offset) {
		data_blob_free(&dce_conn->partial_input);
		return;
	}

	blob = dce_conn->partial_input;
	dce_conn->partial_input = data_blob(blob.data + offset,
					    blob.length - offset);
	data_blob_free(&blob);
}

/*
  remove the call from the right list when freed
 */
static int dcesrv_call_dequeue(struct dcesrv_call_state *call)
{
	dcesrv_call_set_list(call, DCESRV_LIST_NONE);
	return 0;
}

/*
  process some input to a dcerpc endpoint server.
*/
NTSTATUS dcesrv_input_process(struct dcesrv_connection *dce_conn)
{
	struct ndr_pull *ndr;
	enum ndr_err_code ndr_err;
	NTSTATUS status;
	struct dcesrv_call_state *call;
	DATA_BLOB blob;

	call = talloc_zero(dce_conn, struct dcesrv_call_state);
	if (!call) {
		talloc_free(dce_conn->partial_input.data);
		return NT_STATUS_NO_MEMORY;
	}
	call->conn		= dce_conn;
	call->event_ctx		= dce_conn->event_ctx;
	call->msg_ctx		= dce_conn->msg_ctx;
	call->state_flags	= call->conn->state_flags;
	call->time		= timeval_current();
	call->list              = DCESRV_LIST_NONE;

	talloc_set_destructor(call, dcesrv_call_dequeue);

	blob = dce_conn->partial_input;
	blob.length = dcerpc_get_frag_length(&blob);

	ndr = ndr_pull_init_blob(&blob, call, lp_iconv_convenience(call->conn->dce_ctx->lp_ctx));
	if (!ndr) {
		talloc_free(dce_conn->partial_input.data);
		talloc_free(call);
		return NT_STATUS_NO_MEMORY;
	}

	if (!(CVAL(blob.data, DCERPC_DREP_OFFSET) & DCERPC_DREP_LE)) {
		ndr->flags |= LIBNDR_FLAG_BIGENDIAN;
	}

	ndr_err = ndr_pull_ncacn_packet(ndr, NDR_SCALARS|NDR_BUFFERS, &call->pkt);
	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		talloc_free(dce_conn->partial_input.data);
		talloc_free(call);
		return ndr_map_error2ntstatus(ndr_err);
	}

	/* we have to check the signing here, before combining the
	   pdus */
	if (call->pkt.ptype == DCERPC_PKT_REQUEST &&
	    !dcesrv_auth_request(call, &blob)) {
		dce_partial_advance(dce_conn, blob.length);
		return dcesrv_fault(call, DCERPC_FAULT_ACCESS_DENIED);		
	}

	dce_partial_advance(dce_conn, blob.length);

	/* see if this is a continued packet */
	if (call->pkt.ptype == DCERPC_PKT_REQUEST &&
	    !(call->pkt.pfc_flags & DCERPC_PFC_FLAG_FIRST)) {
		struct dcesrv_call_state *call2 = call;
		uint32_t alloc_size;

		/* we only allow fragmented requests, no other packet types */
		if (call->pkt.ptype != DCERPC_PKT_REQUEST) {
			return dcesrv_fault(call2, DCERPC_FAULT_OTHER);
		}

		/* this is a continuation of an existing call - find the call then
		   tack it on the end */
		call = dcesrv_find_fragmented_call(dce_conn, call2->pkt.call_id);
		if (!call) {
			return dcesrv_fault(call2, DCERPC_FAULT_OTHER);
		}

		if (call->pkt.ptype != call2->pkt.ptype) {
			/* trying to play silly buggers are we? */
			return dcesrv_fault(call2, DCERPC_FAULT_OTHER);
		}

		alloc_size = call->pkt.u.request.stub_and_verifier.length +
			call2->pkt.u.request.stub_and_verifier.length;
		if (call->pkt.u.request.alloc_hint > alloc_size) {
			alloc_size = call->pkt.u.request.alloc_hint;
		}

		call->pkt.u.request.stub_and_verifier.data = 
			talloc_realloc(call, 
				       call->pkt.u.request.stub_and_verifier.data, 
				       uint8_t, alloc_size);
		if (!call->pkt.u.request.stub_and_verifier.data) {
			return dcesrv_fault(call2, DCERPC_FAULT_OTHER);
		}
		memcpy(call->pkt.u.request.stub_and_verifier.data +
		       call->pkt.u.request.stub_and_verifier.length,
		       call2->pkt.u.request.stub_and_verifier.data,
		       call2->pkt.u.request.stub_and_verifier.length);
		call->pkt.u.request.stub_and_verifier.length += 
			call2->pkt.u.request.stub_and_verifier.length;

		call->pkt.pfc_flags |= (call2->pkt.pfc_flags & DCERPC_PFC_FLAG_LAST);

		talloc_free(call2);
	}

	/* this may not be the last pdu in the chain - if its isn't then
	   just put it on the incoming_fragmented_call_list and wait for the rest */
	if (call->pkt.ptype == DCERPC_PKT_REQUEST &&
	    !(call->pkt.pfc_flags & DCERPC_PFC_FLAG_LAST)) {
		dcesrv_call_set_list(call, DCESRV_LIST_FRAGMENTED_CALL_LIST);
		return NT_STATUS_OK;
	} 
	
	/* This removes any fragments we may have had stashed away */
	dcesrv_call_set_list(call, DCESRV_LIST_NONE);

	switch (call->pkt.ptype) {
	case DCERPC_PKT_BIND:
		status = dcesrv_bind(call);
		break;
	case DCERPC_PKT_AUTH3:
		status = dcesrv_auth3(call);
		break;
	case DCERPC_PKT_ALTER:
		status = dcesrv_alter(call);
		break;
	case DCERPC_PKT_REQUEST:
		status = dcesrv_request(call);
		break;
	default:
		status = NT_STATUS_INVALID_PARAMETER;
		break;
	}

	/* if we are going to be sending a reply then add
	   it to the list of pending calls. We add it to the end to keep the call
	   list in the order we will answer */
	if (!NT_STATUS_IS_OK(status)) {
		talloc_free(call);
	}

	return status;
}


/*
  provide some input to a dcerpc endpoint server. This passes data
  from a dcerpc client into the server
*/
_PUBLIC_ NTSTATUS dcesrv_input(struct dcesrv_connection *dce_conn, const DATA_BLOB *data)
{
	NTSTATUS status;

	dce_conn->partial_input.data = talloc_realloc(dce_conn,
						      dce_conn->partial_input.data,
						      uint8_t,
						      dce_conn->partial_input.length + data->length);
	if (!dce_conn->partial_input.data) {
		return NT_STATUS_NO_MEMORY;
	}
	memcpy(dce_conn->partial_input.data + dce_conn->partial_input.length,
	       data->data, data->length);
	dce_conn->partial_input.length += data->length;

	while (dce_full_packet(&dce_conn->partial_input)) {
		status = dcesrv_input_process(dce_conn);
		if (!NT_STATUS_IS_OK(status)) {
			return status;
		}
	}

	return NT_STATUS_OK;
}

/*
  retrieve some output from a dcerpc server
  The caller supplies a function that will be called to do the
  actual output. 

  The first argument to write_fn() will be 'private', the second will
  be a pointer to a buffer containing the data to be sent and the 3rd
  will be a pointer to a size_t variable that will be set to the
  number of bytes that are consumed from the output.

  from the current fragment
*/
_PUBLIC_ NTSTATUS dcesrv_output(struct dcesrv_connection *dce_conn, 
		       void *private_data,
		       NTSTATUS (*write_fn)(void *private_data, DATA_BLOB *output, size_t *nwritten))
{
	NTSTATUS status;
	struct dcesrv_call_state *call;
	struct data_blob_list_item *rep;
	size_t nwritten;

	call = dce_conn->call_list;
	if (!call || !call->replies) {
		if (dce_conn->pending_call_list) {
			/* TODO: we need to say act async here
			 *       as we know we have pending requests
			 *	 which will be finished at a time
			 */
			return NT_STATUS_FOOBAR;
		}
		return NT_STATUS_FOOBAR;
	}
	rep = call->replies;

	status = write_fn(private_data, &rep->blob, &nwritten);
	NT_STATUS_IS_ERR_RETURN(status);

	rep->blob.length -= nwritten;
	rep->blob.data += nwritten;

	if (rep->blob.length == 0) {
		/* we're done with this section of the call */
		DLIST_REMOVE(call->replies, rep);
	}

	if (call->replies == NULL) {
		/* we're done with the whole call */
		dcesrv_call_set_list(call, DCESRV_LIST_NONE);
		talloc_free(call);
	}

	return status;
}

_PUBLIC_ NTSTATUS dcesrv_init_context(TALLOC_CTX *mem_ctx, 
				      struct loadparm_context *lp_ctx,
				      const char **endpoint_servers, struct dcesrv_context **_dce_ctx)
{
	NTSTATUS status;
	struct dcesrv_context *dce_ctx;
	int i;

	if (!endpoint_servers) {
		DEBUG(0,("dcesrv_init_context: no endpoint servers configured\n"));
		return NT_STATUS_INTERNAL_ERROR;
	}

	dce_ctx = talloc(mem_ctx, struct dcesrv_context);
	NT_STATUS_HAVE_NO_MEMORY(dce_ctx);
	dce_ctx->endpoint_list	= NULL;
	dce_ctx->lp_ctx = lp_ctx;

	for (i=0;endpoint_servers[i];i++) {
		const struct dcesrv_endpoint_server *ep_server;

		ep_server = dcesrv_ep_server_byname(endpoint_servers[i]);
		if (!ep_server) {
			DEBUG(0,("dcesrv_init_context: failed to find endpoint server = '%s'\n", endpoint_servers[i]));
			return NT_STATUS_INTERNAL_ERROR;
		}

		status = ep_server->init_server(dce_ctx, ep_server);
		if (!NT_STATUS_IS_OK(status)) {
			DEBUG(0,("dcesrv_init_context: failed to init endpoint server = '%s': %s\n", endpoint_servers[i],
				nt_errstr(status)));
			return status;
		}
	}

	*_dce_ctx = dce_ctx;
	return NT_STATUS_OK;
}

/* the list of currently registered DCERPC endpoint servers.
 */
static struct ep_server {
	struct dcesrv_endpoint_server *ep_server;
} *ep_servers = NULL;
static int num_ep_servers;

/*
  register a DCERPC endpoint server. 

  The 'name' can be later used by other backends to find the operations
  structure for this backend.  

  The 'type' is used to specify whether this is for a disk, printer or IPC$ share
*/
_PUBLIC_ NTSTATUS dcerpc_register_ep_server(const void *_ep_server)
{
	const struct dcesrv_endpoint_server *ep_server = _ep_server;
	
	if (dcesrv_ep_server_byname(ep_server->name) != NULL) {
		/* its already registered! */
		DEBUG(0,("DCERPC endpoint server '%s' already registered\n", 
			 ep_server->name));
		return NT_STATUS_OBJECT_NAME_COLLISION;
	}

	ep_servers = realloc_p(ep_servers, struct ep_server, num_ep_servers+1);
	if (!ep_servers) {
		smb_panic("out of memory in dcerpc_register");
	}

	ep_servers[num_ep_servers].ep_server = smb_xmemdup(ep_server, sizeof(*ep_server));
	ep_servers[num_ep_servers].ep_server->name = smb_xstrdup(ep_server->name);

	num_ep_servers++;

	DEBUG(3,("DCERPC endpoint server '%s' registered\n", 
		 ep_server->name));

	return NT_STATUS_OK;
}

/*
  return the operations structure for a named backend of the specified type
*/
const struct dcesrv_endpoint_server *dcesrv_ep_server_byname(const char *name)
{
	int i;

	for (i=0;i<num_ep_servers;i++) {
		if (strcmp(ep_servers[i].ep_server->name, name) == 0) {
			return ep_servers[i].ep_server;
		}
	}

	return NULL;
}

/*
  return the DCERPC module version, and the size of some critical types
  This can be used by endpoint server modules to either detect compilation errors, or provide
  multiple implementations for different smbd compilation options in one module
*/
const struct dcesrv_critical_sizes *dcerpc_module_version(void)
{
	static const struct dcesrv_critical_sizes critical_sizes = {
		DCERPC_MODULE_VERSION,
		sizeof(struct dcesrv_context),
		sizeof(struct dcesrv_endpoint),
		sizeof(struct dcesrv_endpoint_server),
		sizeof(struct dcesrv_interface),
		sizeof(struct dcesrv_if_list),
		sizeof(struct dcesrv_connection),
		sizeof(struct dcesrv_call_state),
		sizeof(struct dcesrv_auth),
		sizeof(struct dcesrv_handle)
	};

	return &critical_sizes;
}

/*
  initialise the dcerpc server context for ncacn_np based services
*/
_PUBLIC_ NTSTATUS dcesrv_init_ipc_context(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx,
					  struct dcesrv_context **_dce_ctx)
{
	NTSTATUS status;
	struct dcesrv_context *dce_ctx;

	status = dcesrv_init_context(mem_ctx, lp_ctx, lp_dcerpc_endpoint_servers(lp_ctx), &dce_ctx);
	NT_STATUS_NOT_OK_RETURN(status);

	*_dce_ctx = dce_ctx;
	return NT_STATUS_OK;
}