summaryrefslogtreecommitdiff
path: root/source4/librpc/rpc/dcerpc_util.c
blob: ffe8506d2112f42dc5e171a8ef401aeec5c21182 (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
/* 
   Unix SMB/CIFS implementation.

   dcerpc utility functions

   Copyright (C) Andrew Tridgell 2003
   Copyright (C) Jelmer Vernooij 2004
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
   Copyright (C) Rafal Szczesniak 2006
   
   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 "lib/events/events.h"
#include "libcli/composite/composite.h"
#include "librpc/gen_ndr/ndr_epmapper_c.h"
#include "librpc/gen_ndr/ndr_dcerpc.h"
#include "librpc/gen_ndr/ndr_misc.h"
#include "librpc/rpc/dcerpc_proto.h"
#include "auth/credentials/credentials.h"
#include "param/param.h"

/*
  find a dcerpc call on an interface by name
*/
const struct ndr_interface_call *dcerpc_iface_find_call(const struct ndr_interface_table *iface,
							const char *name)
{
	int i;
	for (i=0;i<iface->num_calls;i++) {
		if (strcmp(iface->calls[i].name, name) == 0) {
			return &iface->calls[i];
		}
	}
	return NULL;
}

/* 
   push a ncacn_packet into a blob, potentially with auth info
*/
NTSTATUS ncacn_push_auth(DATA_BLOB *blob, TALLOC_CTX *mem_ctx, 
			 struct ncacn_packet *pkt,
			 struct dcerpc_auth *auth_info)
{
	struct ndr_push *ndr;
	enum ndr_err_code ndr_err;

	ndr = ndr_push_init_ctx(mem_ctx);
	if (!ndr) {
		return NT_STATUS_NO_MEMORY;
	}

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

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

	if (auth_info) {
		pkt->auth_length = auth_info->credentials.length;
	} else {
		pkt->auth_length = 0;
	}

	ndr_err = ndr_push_ncacn_packet(ndr, NDR_SCALARS|NDR_BUFFERS, pkt);
	if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
		return ndr_map_error2ntstatus(ndr_err);
	}

	if (auth_info) {
#if 0
		/* the s3 rpc server doesn't handle auth padding in
		   bind requests. Use zero auth padding to keep us
		   working with old servers */
		uint32_t offset = ndr->offset;
		ndr_err = ndr_push_align(ndr, 16);
		if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
			return ndr_map_error2ntstatus(ndr_err);
		}
		auth_info->auth_pad_length = ndr->offset - offset;
#else
		auth_info->auth_pad_length = 0;
#endif
		ndr_err = ndr_push_dcerpc_auth(ndr, NDR_SCALARS|NDR_BUFFERS, auth_info);
		if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
			return ndr_map_error2ntstatus(ndr_err);
		}
	}

	*blob = ndr_push_blob(ndr);

	/* fill in the frag length */
	dcerpc_set_frag_length(blob, blob->length);

	return NT_STATUS_OK;
}


struct epm_map_binding_state {
	struct dcerpc_binding *binding;
	const struct ndr_interface_table *table;
	struct dcerpc_pipe *pipe;
	struct policy_handle handle;
	struct GUID guid;
	struct epm_twr_t twr;
	struct epm_twr_t *twr_r;
	uint32_t num_towers;
	struct epm_Map r;
};


static void continue_epm_recv_binding(struct composite_context *ctx);
static void continue_epm_map(struct tevent_req *subreq);


/*
  Stage 2 of epm_map_binding: Receive connected rpc pipe and send endpoint
  mapping rpc request
*/
static void continue_epm_recv_binding(struct composite_context *ctx)
{
	struct composite_context *c = talloc_get_type(ctx->async.private_data,
						      struct composite_context);
	struct epm_map_binding_state *s = talloc_get_type(c->private_data,
							  struct epm_map_binding_state);
	struct tevent_req *subreq;

	/* receive result of rpc pipe connect request */
	c->status = dcerpc_pipe_connect_b_recv(ctx, c, &s->pipe);
	if (!composite_is_ok(c)) return;

	/* prepare requested binding parameters */
	s->binding->object         = s->table->syntax_id;

	c->status = dcerpc_binding_build_tower(s->pipe, s->binding, &s->twr.tower);
	if (!composite_is_ok(c)) return;
	
	/* with some nice pretty paper around it of course */
	s->r.in.object        = &s->guid;
	s->r.in.map_tower     = &s->twr;
	s->r.in.entry_handle  = &s->handle;
	s->r.in.max_towers    = 1;
	s->r.out.entry_handle = &s->handle;
	s->r.out.num_towers   = &s->num_towers;

	/* send request for an endpoint mapping - a rpc request on connected pipe */
	subreq = dcerpc_epm_Map_r_send(s, c->event_ctx,
				       s->pipe->binding_handle,
				       &s->r);
	if (composite_nomem(subreq, c)) return;
	
	tevent_req_set_callback(subreq, continue_epm_map, c);
}


/*
  Stage 3 of epm_map_binding: Receive endpoint mapping and provide binding details
*/
static void continue_epm_map(struct tevent_req *subreq)
{
	struct composite_context *c = tevent_req_callback_data(subreq,
				      struct composite_context);
	struct epm_map_binding_state *s = talloc_get_type(c->private_data,
							  struct epm_map_binding_state);

	/* receive result of a rpc request */
	c->status = dcerpc_epm_Map_r_recv(subreq, s);
	TALLOC_FREE(subreq);
	if (!composite_is_ok(c)) return;

	/* check the details */
	if (s->r.out.result != 0 || *s->r.out.num_towers != 1) {
		composite_error(c, NT_STATUS_PORT_UNREACHABLE);
		return;
	}
	
	s->twr_r = s->r.out.towers[0].twr;
	if (s->twr_r == NULL) {
		composite_error(c, NT_STATUS_PORT_UNREACHABLE);
		return;
	}

	if (s->twr_r->tower.num_floors != s->twr.tower.num_floors ||
	    s->twr_r->tower.floors[3].lhs.protocol != s->twr.tower.floors[3].lhs.protocol) {
		composite_error(c, NT_STATUS_PORT_UNREACHABLE);
		return;
	}

	/* get received endpoint */
	s->binding->endpoint = talloc_reference(s->binding,
						dcerpc_floor_get_rhs_data(c, &s->twr_r->tower.floors[3]));
	if (composite_nomem(s->binding->endpoint, c)) return;

	composite_done(c);
}


/*
  Request for endpoint mapping of dcerpc binding - try to request for endpoint
  unless there is default one.
*/
struct composite_context *dcerpc_epm_map_binding_send(TALLOC_CTX *mem_ctx,
						      struct dcerpc_binding *binding,
						      const struct ndr_interface_table *table,
						      struct tevent_context *ev,
						      struct loadparm_context *lp_ctx)
{
	struct composite_context *c;
	struct epm_map_binding_state *s;
	struct composite_context *pipe_connect_req;
	struct cli_credentials *anon_creds;

	NTSTATUS status;
	struct dcerpc_binding *epmapper_binding;
	int i;

	if (ev == NULL) {
		return NULL;
	}

	/* composite context allocation and setup */
	c = composite_create(mem_ctx, ev);
	if (c == NULL) {
		return NULL;
	}

	s = talloc_zero(c, struct epm_map_binding_state);
	if (composite_nomem(s, c)) return c;
	c->private_data = s;

	s->binding = binding;
	s->table   = table;

	/* anonymous credentials for rpc connection used to get endpoint mapping */
	anon_creds = cli_credentials_init(mem_ctx);
	cli_credentials_set_anonymous(anon_creds);

	/*
	  First, check if there is a default endpoint specified in the IDL
	*/
	if (table != NULL) {
		struct dcerpc_binding *default_binding;

		/* Find one of the default pipes for this interface */
		for (i = 0; i < table->endpoints->count; i++) {
			status = dcerpc_parse_binding(mem_ctx, table->endpoints->names[i], &default_binding);

			if (NT_STATUS_IS_OK(status)) {
				if (binding->transport == NCA_UNKNOWN) 
					binding->transport = default_binding->transport;
				if (default_binding->transport == binding->transport && 
					default_binding->endpoint) {
					binding->endpoint = talloc_reference(binding, default_binding->endpoint);
					talloc_free(default_binding);

					composite_done(c);
					return c;

				} else {
					talloc_free(default_binding);
				}
			}
		}
	}

	epmapper_binding = talloc_zero(c, struct dcerpc_binding);
	if (composite_nomem(epmapper_binding, c)) return c;

	/* basic endpoint mapping data */
	epmapper_binding->transport		= binding->transport;
	epmapper_binding->host			= talloc_reference(epmapper_binding, binding->host);
	epmapper_binding->target_hostname       = epmapper_binding->host;
	epmapper_binding->options		= NULL;
	epmapper_binding->flags			= 0;
	epmapper_binding->assoc_group_id	= 0;
	epmapper_binding->endpoint		= NULL;

	/* initiate rpc pipe connection */
	pipe_connect_req = dcerpc_pipe_connect_b_send(c, epmapper_binding, 
						      &ndr_table_epmapper,
						      anon_creds, c->event_ctx,
						      lp_ctx);
	if (composite_nomem(pipe_connect_req, c)) return c;
	
	composite_continue(c, pipe_connect_req, continue_epm_recv_binding, c);
	return c;
}


/*
  Receive result of endpoint mapping request
 */
NTSTATUS dcerpc_epm_map_binding_recv(struct composite_context *c)
{
	NTSTATUS status = composite_wait(c);
	
	talloc_free(c);
	return status;
}


/*
  Get endpoint mapping for rpc connection
*/
_PUBLIC_ NTSTATUS dcerpc_epm_map_binding(TALLOC_CTX *mem_ctx, struct dcerpc_binding *binding,
				const struct ndr_interface_table *table, struct tevent_context *ev,
				struct loadparm_context *lp_ctx)
{
	struct composite_context *c;

	c = dcerpc_epm_map_binding_send(mem_ctx, binding, table, ev, lp_ctx);
	return dcerpc_epm_map_binding_recv(c);
}


struct pipe_auth_state {
	struct dcerpc_pipe *pipe;
	struct dcerpc_binding *binding;
	const struct ndr_interface_table *table;
	struct loadparm_context *lp_ctx;
	struct cli_credentials *credentials;
};


static void continue_auth_schannel(struct composite_context *ctx);
static void continue_auth(struct composite_context *ctx);
static void continue_auth_none(struct composite_context *ctx);
static void continue_ntlmssp_connection(struct composite_context *ctx);
static void continue_spnego_after_wrong_pass(struct composite_context *ctx);


/*
  Stage 2 of pipe_auth: Receive result of schannel bind request
*/
static void continue_auth_schannel(struct composite_context *ctx)
{
	struct composite_context *c = talloc_get_type(ctx->async.private_data,
						      struct composite_context);

	c->status = dcerpc_bind_auth_schannel_recv(ctx);
	if (!composite_is_ok(c)) return;

	composite_done(c);
}


/*
  Stage 2 of pipe_auth: Receive result of authenticated bind request
*/
static void continue_auth(struct composite_context *ctx)
{
	struct composite_context *c = talloc_get_type(ctx->async.private_data,
						      struct composite_context);

	c->status = dcerpc_bind_auth_recv(ctx);
	if (!composite_is_ok(c)) return;
	
	composite_done(c);
}
/*
  Stage 2 of pipe_auth: Receive result of authenticated bind request, but handle fallbacks:
  SPNEGO -> NTLMSSP
*/
static void continue_auth_auto(struct composite_context *ctx)
{
	struct composite_context *c = talloc_get_type(ctx->async.private_data,
						      struct composite_context);
	struct pipe_auth_state *s = talloc_get_type(c->private_data, struct pipe_auth_state);
	struct composite_context *sec_conn_req;

	c->status = dcerpc_bind_auth_recv(ctx);
	if (NT_STATUS_EQUAL(c->status, NT_STATUS_INVALID_PARAMETER)) {
		/*
		 * Retry with NTLMSSP auth as fallback
		 * send a request for secondary rpc connection
		 */
		sec_conn_req = dcerpc_secondary_connection_send(s->pipe,
								s->binding);
		composite_continue(c, sec_conn_req, continue_ntlmssp_connection, c);
		return;
	} else if (NT_STATUS_EQUAL(c->status, NT_STATUS_LOGON_FAILURE)) {
		if (cli_credentials_wrong_password(s->credentials)) {
			/*
			 * Retry SPNEGO with a better password
			 * send a request for secondary rpc connection
			 */
			sec_conn_req = dcerpc_secondary_connection_send(s->pipe,
									s->binding);
			composite_continue(c, sec_conn_req, continue_spnego_after_wrong_pass, c);
			return;
		}
	}

	if (!composite_is_ok(c)) return;

	composite_done(c);
}

/*
  Stage 3 of pipe_auth (fallback to NTLMSSP case): Receive secondary
  rpc connection (the first one can't be used any more, due to the
  bind nak) and perform authenticated bind request
*/
static void continue_ntlmssp_connection(struct composite_context *ctx)
{
	struct composite_context *c;
	struct pipe_auth_state *s;
	struct composite_context *auth_req;
	struct dcerpc_pipe *p2;
	void *pp;

	c = talloc_get_type(ctx->async.private_data, struct composite_context);
	s = talloc_get_type(c->private_data, struct pipe_auth_state);

	/* receive secondary rpc connection */
	c->status = dcerpc_secondary_connection_recv(ctx, &p2);
	if (!composite_is_ok(c)) return;


	/* this is a rather strange situation. When
	   we come into the routine, s is a child of s->pipe, and
	   when we created p2 above, it also became a child of
	   s->pipe.

	   Now we want p2 to be a parent of s->pipe, and we want s to
	   be a parent of both of them! If we don't do this very
	   carefully we end up creating a talloc loop
	*/

	/* we need the new contexts to hang off the same context
	   that s->pipe is on, but the only way to get that is
	   via talloc_parent() */
	pp = talloc_parent(s->pipe);

	/* promote s to be at the top */
	talloc_steal(pp, s);

	/* and put p2 under s */
	talloc_steal(s, p2);

	/* now put s->pipe under p2 */
	talloc_steal(p2, s->pipe);

	s->pipe = p2;

	/* initiate a authenticated bind */
	auth_req = dcerpc_bind_auth_send(c, s->pipe, s->table,
					 s->credentials, 
					 lpcfg_gensec_settings(c, s->lp_ctx),
					 DCERPC_AUTH_TYPE_NTLMSSP,
					 dcerpc_auth_level(s->pipe->conn),
					 s->table->authservices->names[0]);
	composite_continue(c, auth_req, continue_auth, c);
}

/*
  Stage 3 of pipe_auth (retry on wrong password): Receive secondary
  rpc connection (the first one can't be used any more, due to the
  bind nak) and perform authenticated bind request
*/
static void continue_spnego_after_wrong_pass(struct composite_context *ctx)
{
	struct composite_context *c;
	struct pipe_auth_state *s;
	struct composite_context *auth_req;
	struct dcerpc_pipe *p2;

	c = talloc_get_type(ctx->async.private_data, struct composite_context);
	s = talloc_get_type(c->private_data, struct pipe_auth_state);

	/* receive secondary rpc connection */
	c->status = dcerpc_secondary_connection_recv(ctx, &p2);
	if (!composite_is_ok(c)) return;

	talloc_steal(s, p2);
	talloc_steal(p2, s->pipe);
	s->pipe = p2;

	/* initiate a authenticated bind */
	auth_req = dcerpc_bind_auth_send(c, s->pipe, s->table,
					 s->credentials, 
					 lpcfg_gensec_settings(c, s->lp_ctx),
					 DCERPC_AUTH_TYPE_SPNEGO,
					 dcerpc_auth_level(s->pipe->conn),
					 s->table->authservices->names[0]);
	composite_continue(c, auth_req, continue_auth, c);
}


/*
  Stage 2 of pipe_auth: Receive result of non-authenticated bind request
*/
static void continue_auth_none(struct composite_context *ctx)
{
	struct composite_context *c = talloc_get_type(ctx->async.private_data,
						      struct composite_context);

	c->status = dcerpc_bind_auth_none_recv(ctx);
	if (!composite_is_ok(c)) return;
	
	composite_done(c);
}


/*
  Request to perform an authenticated bind if required. Authentication
  is determined using credentials passed and binding flags.
*/
struct composite_context *dcerpc_pipe_auth_send(struct dcerpc_pipe *p, 
						struct dcerpc_binding *binding,
						const struct ndr_interface_table *table,
						struct cli_credentials *credentials,
						struct loadparm_context *lp_ctx)
{
	struct composite_context *c;
	struct pipe_auth_state *s;
	struct composite_context *auth_schannel_req;
	struct composite_context *auth_req;
	struct composite_context *auth_none_req;
	struct dcerpc_connection *conn;
	uint8_t auth_type;

	/* composite context allocation and setup */
	c = composite_create(p, p->conn->event_ctx);
	if (c == NULL) return NULL;

	s = talloc_zero(c, struct pipe_auth_state);
	if (composite_nomem(s, c)) return c;
	c->private_data = s;

	/* store parameters in state structure */
	s->binding      = binding;
	s->table        = table;
	s->credentials  = credentials;
	s->pipe         = p;
	s->lp_ctx       = lp_ctx;

	conn = s->pipe->conn;
	conn->flags = binding->flags;

	if (DEBUGLVL(100)) {
		conn->flags |= DCERPC_DEBUG_PRINT_BOTH;
	}
	
	/* remember the binding string for possible secondary connections */
	conn->binding_string = dcerpc_binding_string(p, binding);

	if (cli_credentials_is_anonymous(s->credentials)) {
		auth_none_req = dcerpc_bind_auth_none_send(c, s->pipe, s->table);
		composite_continue(c, auth_none_req, continue_auth_none, c);
		return c;
	}

	if ((binding->flags & DCERPC_SCHANNEL) &&
	    !cli_credentials_get_netlogon_creds(s->credentials)) {
		/* If we don't already have netlogon credentials for
		 * the schannel bind, then we have to get these
		 * first */
		auth_schannel_req = dcerpc_bind_auth_schannel_send(c, s->pipe, s->table,
								   s->credentials, s->lp_ctx,
								   dcerpc_auth_level(conn));
		composite_continue(c, auth_schannel_req, continue_auth_schannel, c);
		return c;
	}

	/*
	 * we rely on the already authenticated CIFS connection
	 * if not doing sign or seal
	 */
	if (conn->transport.transport == NCACN_NP &&
	    !(s->binding->flags & (DCERPC_SIGN|DCERPC_SEAL))) {
		auth_none_req = dcerpc_bind_auth_none_send(c, s->pipe, s->table);
		composite_continue(c, auth_none_req, continue_auth_none, c);
		return c;
	}


	/* Perform an authenticated DCE-RPC bind
	 */
	if (!(conn->flags & (DCERPC_SIGN|DCERPC_SEAL))) {
		/*
		  we are doing an authenticated connection,
		  but not using sign or seal. We must force
		  the CONNECT dcerpc auth type as a NONE auth
		  type doesn't allow authentication
		  information to be passed.
		*/
		conn->flags |= DCERPC_CONNECT;
	}

	if (s->binding->flags & DCERPC_AUTH_SPNEGO) {
		auth_type = DCERPC_AUTH_TYPE_SPNEGO;

	} else if (s->binding->flags & DCERPC_AUTH_KRB5) {
		auth_type = DCERPC_AUTH_TYPE_KRB5;

	} else if (s->binding->flags & DCERPC_SCHANNEL) {
		auth_type = DCERPC_AUTH_TYPE_SCHANNEL;

	} else if (s->binding->flags & DCERPC_AUTH_NTLM) {
		auth_type = DCERPC_AUTH_TYPE_NTLMSSP;

	} else {
		/* try SPNEGO with fallback to NTLMSSP */
		auth_req = dcerpc_bind_auth_send(c, s->pipe, s->table,
						 s->credentials, 
						 lpcfg_gensec_settings(c, s->lp_ctx),
						 DCERPC_AUTH_TYPE_SPNEGO,
						 dcerpc_auth_level(conn),
						 s->table->authservices->names[0]);
		composite_continue(c, auth_req, continue_auth_auto, c);
		return c;
	}

	auth_req = dcerpc_bind_auth_send(c, s->pipe, s->table,
					 s->credentials, 
					 lpcfg_gensec_settings(c, s->lp_ctx),
					 auth_type,
					 dcerpc_auth_level(conn),
					 s->table->authservices->names[0]);
	composite_continue(c, auth_req, continue_auth, c);
	return c;
}


/*
  Receive result of authenticated bind request on dcerpc pipe

  This returns *p, which may be different to the one originally
  supllied, as it rebinds to a new pipe due to authentication fallback

*/
NTSTATUS dcerpc_pipe_auth_recv(struct composite_context *c, TALLOC_CTX *mem_ctx, 
			       struct dcerpc_pipe **p)
{
	NTSTATUS status;

	struct pipe_auth_state *s = talloc_get_type(c->private_data,
						    struct pipe_auth_state);
	status = composite_wait(c);
	if (!NT_STATUS_IS_OK(status)) {
		char *uuid_str = GUID_string(s->pipe, &s->table->syntax_id.uuid);
		DEBUG(0, ("Failed to bind to uuid %s - %s\n", uuid_str, nt_errstr(status)));
		talloc_free(uuid_str);
	} else {
		talloc_steal(mem_ctx, s->pipe);
		*p = s->pipe;
	}

	talloc_free(c);
	return status;
}


/* 
   Perform an authenticated bind if needed - sync version

   This may change *p, as it rebinds to a new pipe due to authentication fallback
*/
_PUBLIC_ NTSTATUS dcerpc_pipe_auth(TALLOC_CTX *mem_ctx,
			  struct dcerpc_pipe **p, 
			  struct dcerpc_binding *binding,
			  const struct ndr_interface_table *table,
			  struct cli_credentials *credentials,
			  struct loadparm_context *lp_ctx)
{
	struct composite_context *c;

	c = dcerpc_pipe_auth_send(*p, binding, table, credentials, lp_ctx);
	return dcerpc_pipe_auth_recv(c, mem_ctx, p);
}


NTSTATUS dcerpc_generic_session_key(struct dcerpc_connection *c,
				    DATA_BLOB *session_key)
{
	/* this took quite a few CPU cycles to find ... */
	session_key->data = discard_const_p(unsigned char, "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 dcerpc_fetch_session_key(struct dcerpc_pipe *p,
					   DATA_BLOB *session_key)
{
	NTSTATUS status;
	status = p->conn->security_state.session_key(p->conn, session_key);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

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

	return NT_STATUS_OK;
}


/*
  log a rpc packet in a format suitable for ndrdump. This is especially useful
  for sealed packets, where ethereal cannot easily see the contents

  this triggers on a debug level of >= 10
*/
_PUBLIC_ void dcerpc_log_packet(const char *lockdir,
				const struct ndr_interface_table *ndr,
				uint32_t opnum, uint32_t flags,
				const DATA_BLOB *pkt)
{
	const int num_examples = 20;
	int i;

	if (lockdir == NULL) return;

	for (i=0;i<num_examples;i++) {
		char *name=NULL;
		asprintf(&name, "%s/rpclog/%s-%u.%d.%s", 
			 lockdir, ndr->name, opnum, i,
			 (flags&NDR_IN)?"in":"out");
		if (name == NULL) {
			return;
		}
		if (!file_exist(name)) {
			if (file_save(name, pkt->data, pkt->length)) {
				DEBUG(10,("Logged rpc packet to %s\n", name));
			}
			free(name);
			break;
		}
		free(name);
	}
}



/*
  create a secondary context from a primary connection

  this uses dcerpc_alter_context() to create a new dcerpc context_id
*/
_PUBLIC_ NTSTATUS dcerpc_secondary_context(struct dcerpc_pipe *p, 
				  struct dcerpc_pipe **pp2,
				  const struct ndr_interface_table *table)
{
	NTSTATUS status;
	struct dcerpc_pipe *p2;
	
	p2 = talloc_zero(p, struct dcerpc_pipe);
	if (p2 == NULL) {
		return NT_STATUS_NO_MEMORY;
	}
	p2->conn = talloc_reference(p2, p->conn);
	p2->request_timeout = p->request_timeout;

	p2->context_id = ++p->conn->next_context_id;

	p2->syntax = table->syntax_id;

	p2->transfer_syntax = p->transfer_syntax;

	p2->binding = talloc_reference(p2, p->binding);

	p2->binding_handle = dcerpc_pipe_binding_handle(p2);
	if (p2->binding_handle == NULL) {
		talloc_free(p2);
		return NT_STATUS_NO_MEMORY;
	}

	status = dcerpc_alter_context(p2, p2, &p2->syntax, &p2->transfer_syntax);
	if (!NT_STATUS_IS_OK(status)) {
		talloc_free(p2);
		return status;
	}

	*pp2 = p2;

	return NT_STATUS_OK;
}