summaryrefslogtreecommitdiff
path: root/src/libstrongswan/plugins/x509/x509_crl.c
blob: 4d7e7bd107a4910daa2944307fc141ad6e78daba (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
/*
 * Copyright (C) 2008-2009 Martin Willi
 * Hochschule fuer Technik Rapperswil
 *
 * 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 2 of the License, or (at your
 * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
 *
 * 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.
 */

#include "x509_crl.h"

typedef struct private_x509_crl_t private_x509_crl_t;
typedef struct revoked_t revoked_t;

#include <time.h>

#include <utils/debug.h>
#include <library.h>
#include <asn1/oid.h>
#include <asn1/asn1.h>
#include <asn1/asn1_parser.h>
#include <credentials/certificates/x509.h>
#include <credentials/keys/private_key.h>
#include <collections/linked_list.h>

/**
 * entry for a revoked certificate
 */
struct revoked_t {
	/**
	 * serial of the revoked certificate
	 */
	chunk_t serial;

	/**
	 * date of revocation
	 */
	time_t date;

	/**
	 * reason for revocation
	 */
	crl_reason_t reason;
};

/**
 * private data of x509_crl
 */
struct private_x509_crl_t {

	/**
	 * public functions
	 */
	x509_crl_t public;

	/**
	 * X.509 crl encoding in ASN.1 DER format
	 */
	chunk_t encoding;

	/**
	 * X.509 crl body over which signature is computed
	 */
	chunk_t tbsCertList;

	/**
	 * Version of the X.509 crl
	 */
	u_int version;

	/**
	 * ID representing the crl issuer
	 */
	identification_t *issuer;

	/**
	 * CRL number
	 */
	chunk_t crlNumber;

	/**
	 * Time when the crl was generated
	 */
	time_t thisUpdate;

	/**
	 * Time when an update crl will be available
	 */
	time_t nextUpdate;

	/**
	 * list of revoked certificates as revoked_t
	 */
	linked_list_t *revoked;

	/**
	 * List of Freshest CRL distribution points
	 */
	linked_list_t *crl_uris;

	/**
	 * Authority Key Identifier
	 */
	chunk_t authKeyIdentifier;

	/**
	 * Authority Key Serial Number
	 */
	chunk_t authKeySerialNumber;

	/**
	 * Number of BaseCRL, if a delta CRL
	 */
	chunk_t baseCrlNumber;

	/**
	 * Signature algorithm
	 */
	int algorithm;

	/**
	 * Signature
	 */
	chunk_t signature;

	/**
	 * has this CRL been generated
	 */
	bool generated;

	/**
	 * reference counter
	 */
	refcount_t ref;
};

/**
 * from x509_cert
 */
extern chunk_t x509_parse_authorityKeyIdentifier(chunk_t blob, int level0,
												 chunk_t *authKeySerialNumber);

/**
 * from x509_cert
 */
extern void x509_parse_crlDistributionPoints(chunk_t blob, int level0,
											 linked_list_t *list);

/**
 * from x509_cert
 */
extern chunk_t x509_build_crlDistributionPoints(linked_list_t *list, int extn);

/**
  * ASN.1 definition of an X.509 certificate revocation list
 */
static const asn1Object_t crlObjects[] = {
	{ 0, "certificateList",				ASN1_SEQUENCE,     ASN1_OBJ  }, /*  0 */
	{ 1,   "tbsCertList",				ASN1_SEQUENCE,     ASN1_OBJ  }, /*  1 */
	{ 2,     "version",					ASN1_INTEGER,      ASN1_OPT |
														   ASN1_BODY }, /*  2 */
	{ 2,     "end opt",					ASN1_EOC,          ASN1_END  }, /*  3 */
	{ 2,     "signature",				ASN1_EOC,          ASN1_RAW  }, /*  4 */
	{ 2,     "issuer",					ASN1_SEQUENCE,     ASN1_OBJ  }, /*  5 */
	{ 2,     "thisUpdate",				ASN1_EOC,          ASN1_RAW  }, /*  6 */
	{ 2,     "nextUpdate",				ASN1_EOC,          ASN1_RAW  }, /*  7 */
	{ 2,     "revokedCertificates",		ASN1_SEQUENCE,     ASN1_OPT |
														   ASN1_LOOP }, /*  8 */
	{ 3,       "certList",				ASN1_SEQUENCE,     ASN1_NONE }, /*  9 */
	{ 4,         "userCertificate",		ASN1_INTEGER,      ASN1_BODY }, /* 10 */
	{ 4,         "revocationDate",		ASN1_EOC,          ASN1_RAW  }, /* 11 */
	{ 4,         "crlEntryExtensions",  ASN1_SEQUENCE,     ASN1_OPT |
														   ASN1_LOOP }, /* 12 */
	{ 5,           "extension",			ASN1_SEQUENCE,	   ASN1_NONE }, /* 13 */
	{ 6,             "extnID",			ASN1_OID,          ASN1_BODY }, /* 14 */
	{ 6,             "critical",		ASN1_BOOLEAN,      ASN1_DEF |
														   ASN1_BODY }, /* 15 */
	{ 6,             "extnValue",		ASN1_OCTET_STRING, ASN1_BODY }, /* 16 */
	{ 4,         "end opt or loop",		ASN1_EOC,          ASN1_END  }, /* 17 */
	{ 2,     "end opt or loop",			ASN1_EOC,          ASN1_END  }, /* 18 */
	{ 2,     "optional extensions",		ASN1_CONTEXT_C_0,  ASN1_OPT  }, /* 19 */
	{ 3,       "crlExtensions",			ASN1_SEQUENCE,     ASN1_LOOP }, /* 20 */
	{ 4,         "extension",			ASN1_SEQUENCE,     ASN1_NONE }, /* 21 */
	{ 5,           "extnID",			ASN1_OID,          ASN1_BODY }, /* 22 */
	{ 5,           "critical",			ASN1_BOOLEAN,      ASN1_DEF |
														   ASN1_BODY }, /* 23 */
	{ 5,           "extnValue",			ASN1_OCTET_STRING, ASN1_BODY }, /* 24 */
	{ 3,       "end loop",				ASN1_EOC,          ASN1_END  }, /* 25 */
	{ 2,     "end opt",					ASN1_EOC,          ASN1_END  }, /* 26 */
	{ 1,   "signatureAlgorithm",		ASN1_EOC,          ASN1_RAW  }, /* 27 */
	{ 1,   "signatureValue",			ASN1_BIT_STRING,   ASN1_BODY }, /* 28 */
	{ 0, "exit",						ASN1_EOC,		   ASN1_EXIT }
};
#define CRL_OBJ_TBS_CERT_LIST			 1
#define CRL_OBJ_VERSION					 2
#define CRL_OBJ_SIG_ALG					 4
#define CRL_OBJ_ISSUER					 5
#define CRL_OBJ_THIS_UPDATE				 6
#define CRL_OBJ_NEXT_UPDATE				 7
#define CRL_OBJ_USER_CERTIFICATE		10
#define CRL_OBJ_REVOCATION_DATE			11
#define CRL_OBJ_CRL_ENTRY_EXTN_ID		14
#define CRL_OBJ_CRL_ENTRY_CRITICAL		15
#define CRL_OBJ_CRL_ENTRY_EXTN_VALUE	16
#define CRL_OBJ_EXTN_ID					22
#define CRL_OBJ_CRITICAL				23
#define CRL_OBJ_EXTN_VALUE				24
#define CRL_OBJ_ALGORITHM				27
#define CRL_OBJ_SIGNATURE				28

/**
 *  Parses an X.509 Certificate Revocation List (CRL)
 */
static bool parse(private_x509_crl_t *this)
{
	asn1_parser_t *parser;
	chunk_t object;
	chunk_t extnID = chunk_empty;
	chunk_t userCertificate = chunk_empty;
	int objectID;
	int sig_alg = OID_UNKNOWN;
	bool success = FALSE;
	bool critical = FALSE;
	revoked_t *revoked = NULL;

	parser = asn1_parser_create(crlObjects, this->encoding);

	while (parser->iterate(parser, &objectID, &object))
	{
		u_int level = parser->get_level(parser)+1;

		switch (objectID)
		{
			case CRL_OBJ_TBS_CERT_LIST:
				this->tbsCertList = object;
				break;
			case CRL_OBJ_VERSION:
				this->version = (object.len) ? (1+(u_int)*object.ptr) : 1;
				DBG2(DBG_ASN, "  v%d", this->version);
				break;
			case CRL_OBJ_SIG_ALG:
				sig_alg = asn1_parse_algorithmIdentifier(object, level, NULL);
				break;
			case CRL_OBJ_ISSUER:
				this->issuer = identification_create_from_encoding(ID_DER_ASN1_DN, object);
				DBG2(DBG_ASN, "  '%Y'", this->issuer);
				break;
			case CRL_OBJ_THIS_UPDATE:
				this->thisUpdate = asn1_parse_time(object, level);
				break;
			case CRL_OBJ_NEXT_UPDATE:
				this->nextUpdate = asn1_parse_time(object, level);
				break;
			case CRL_OBJ_USER_CERTIFICATE:
				userCertificate = object;
				break;
			case CRL_OBJ_REVOCATION_DATE:
				revoked = malloc_thing(revoked_t);
				revoked->serial = chunk_clone(userCertificate);
				revoked->date = asn1_parse_time(object, level);
				revoked->reason = CRL_REASON_UNSPECIFIED;
				this->revoked->insert_last(this->revoked, (void *)revoked);
				break;
			case CRL_OBJ_CRL_ENTRY_EXTN_ID:
			case CRL_OBJ_EXTN_ID:
				extnID = object;
				break;
			case CRL_OBJ_CRL_ENTRY_CRITICAL:
			case CRL_OBJ_CRITICAL:
				critical = object.len && *object.ptr;
				DBG2(DBG_ASN, "  %s", critical ? "TRUE" : "FALSE");
				break;
			case CRL_OBJ_CRL_ENTRY_EXTN_VALUE:
			case CRL_OBJ_EXTN_VALUE:
			{
				int extn_oid = asn1_known_oid(extnID);

				switch (extn_oid)
				{
					case OID_CRL_REASON_CODE:
						if (revoked)
						{
							if (object.len && *object.ptr == ASN1_ENUMERATED &&
								asn1_length(&object) == 1)
							{
								revoked->reason = *object.ptr;
							}
							DBG2(DBG_ASN, "  '%N'", crl_reason_names,
								 revoked->reason);
						}
						break;
					case OID_AUTHORITY_KEY_ID:
						this->authKeyIdentifier =
							x509_parse_authorityKeyIdentifier(
									object, level, &this->authKeySerialNumber);
						break;
					case OID_CRL_NUMBER:
						if (!asn1_parse_simple_object(&object, ASN1_INTEGER,
													  level, "crlNumber"))
						{
							goto end;
						}
						this->crlNumber = object;
						break;
					case OID_FRESHEST_CRL:
						x509_parse_crlDistributionPoints(object, level,
														 this->crl_uris);
						break;
					case OID_DELTA_CRL_INDICATOR:
						if (!asn1_parse_simple_object(&object, ASN1_INTEGER,
													level, "deltaCrlIndicator"))
						{
							goto end;
						}
						this->baseCrlNumber = object;
						break;
					case OID_ISSUING_DIST_POINT:
						/* TODO support of IssuingDistributionPoints */
						break;
					default:
						if (critical && lib->settings->get_bool(lib->settings,
							"%s.x509.enforce_critical", TRUE, lib->ns))
						{
							DBG1(DBG_ASN, "critical '%s' extension not supported",
								 (extn_oid == OID_UNKNOWN) ? "unknown" :
								 (char*)oid_names[extn_oid].name);
							goto end;
						}
						break;
				}
				break;
			}
			case CRL_OBJ_ALGORITHM:
			{
				this->algorithm = asn1_parse_algorithmIdentifier(object, level, NULL);
				if (this->algorithm != sig_alg)
				{
					DBG1(DBG_ASN, "  signature algorithms do not agree");
					goto end;
				}
				break;
			}
			case CRL_OBJ_SIGNATURE:
				this->signature = chunk_skip(object, 1);
				break;
			default:
				break;
		}
	}
	success = parser->success(parser);

end:
	parser->destroy(parser);
	return success;
}

/**
 * enumerator filter callback for create_enumerator
 */
static bool filter(void *data, revoked_t **revoked, chunk_t *serial, void *p2,
				   time_t *date, void *p3, crl_reason_t *reason)
{
	if (serial)
	{
		*serial = (*revoked)->serial;
	}
	if (date)
	{
		*date = (*revoked)->date;
	}
	if (reason)
	{
		*reason = (*revoked)->reason;
	}
	return TRUE;
}

METHOD(crl_t, get_serial, chunk_t,
	private_x509_crl_t *this)
{
	return this->crlNumber;
}

METHOD(crl_t, get_authKeyIdentifier, chunk_t,
	private_x509_crl_t *this)
{
	return this->authKeyIdentifier;
}

METHOD(crl_t, is_delta_crl, bool,
	private_x509_crl_t *this, chunk_t *base_crl)
{
	if (this->baseCrlNumber.len)
	{
		if (base_crl)
		{
			*base_crl = this->baseCrlNumber;
		}
		return TRUE;
	}
	return FALSE;
}

METHOD(crl_t, create_delta_crl_uri_enumerator, enumerator_t*,
	private_x509_crl_t *this)
{
	return this->crl_uris->create_enumerator(this->crl_uris);
}

METHOD(crl_t, create_enumerator, enumerator_t*,
	private_x509_crl_t *this)
{
	return enumerator_create_filter(
								this->revoked->create_enumerator(this->revoked),
								(void*)filter, NULL, NULL);
}

METHOD(certificate_t, get_type, certificate_type_t,
	private_x509_crl_t *this)
{
	return CERT_X509_CRL;
}

METHOD(certificate_t, get_issuer, identification_t*,
	private_x509_crl_t *this)
{
	return this->issuer;
}

METHOD(certificate_t, has_issuer, id_match_t,
	private_x509_crl_t *this, identification_t *issuer)
{
	if (issuer->get_type(issuer) == ID_KEY_ID && this->authKeyIdentifier.ptr &&
		chunk_equals(this->authKeyIdentifier, issuer->get_encoding(issuer)))
	{
		return ID_MATCH_PERFECT;
	}
	return this->issuer->matches(this->issuer, issuer);
}

METHOD(certificate_t, issued_by, bool,
	private_x509_crl_t *this, certificate_t *issuer, signature_scheme_t *schemep)
{
	public_key_t *key;
	signature_scheme_t scheme;
	bool valid;
	x509_t *x509 = (x509_t*)issuer;
	chunk_t keyid = chunk_empty;

	/* check if issuer is an X.509 CA certificate */
	if (issuer->get_type(issuer) != CERT_X509)
	{
		return FALSE;
	}
	if (!(x509->get_flags(x509) & (X509_CA | X509_CRL_SIGN)))
	{
		return FALSE;
	}

	/* compare keyIdentifiers if available, otherwise use DNs */
	if (this->authKeyIdentifier.ptr)
	{
		keyid = x509->get_subjectKeyIdentifier(x509);
		if (keyid.len && !chunk_equals(keyid, this->authKeyIdentifier))
		{
			return FALSE;
		}
	}
	if (!keyid.len)
	{
		if (!this->issuer->equals(this->issuer, issuer->get_subject(issuer)))
		{
			return FALSE;
		}
	}

	scheme = signature_scheme_from_oid(this->algorithm);
	if (scheme == SIGN_UNKNOWN)
	{
		return FALSE;
	}
	key = issuer->get_public_key(issuer);
	if (!key)
	{
		return FALSE;
	}
	valid = key->verify(key, scheme, this->tbsCertList, this->signature);
	key->destroy(key);
	if (valid && schemep)
	{
		*schemep = scheme;
	}
	return valid;
}

METHOD(certificate_t, get_public_key, public_key_t*,
	private_x509_crl_t *this)
{
	return NULL;
}

METHOD(certificate_t, get_ref, certificate_t*,
	private_x509_crl_t *this)
{
	ref_get(&this->ref);
	return &this->public.crl.certificate;
}

METHOD(certificate_t, get_validity, bool,
	private_x509_crl_t *this, time_t *when,
	time_t *not_before, time_t *not_after)
{
	time_t t = when ? *when : time(NULL);

	if (not_before)
	{
		*not_before = this->thisUpdate;
	}
	if (not_after)
	{
		*not_after = this->nextUpdate;
	}
	return (t <= this->nextUpdate);
}

METHOD(certificate_t, get_encoding, bool,
	private_x509_crl_t *this, cred_encoding_type_t type, chunk_t *encoding)
{
	if (type == CERT_ASN1_DER)
	{
		*encoding = chunk_clone(this->encoding);
		return TRUE;
	}
	return lib->encoding->encode(lib->encoding, type, NULL, encoding,
					CRED_PART_X509_CRL_ASN1_DER, this->encoding, CRED_PART_END);
}

METHOD(certificate_t, equals, bool,
	private_x509_crl_t *this, certificate_t *other)
{
	chunk_t encoding;
	bool equal;

	if ((certificate_t*)this == other)
	{
		return TRUE;
	}
	if (other->equals == (void*)equals)
	{	/* skip allocation if we have the same implementation */
		return chunk_equals(this->encoding, ((private_x509_crl_t*)other)->encoding);
	}
	if (!other->get_encoding(other, CERT_ASN1_DER, &encoding))
	{
		return FALSE;
	}
	equal = chunk_equals(this->encoding, encoding);
	free(encoding.ptr);
	return equal;
}

/**
 * Destroy a revoked_t entry
 */
static void revoked_destroy(revoked_t *revoked)
{
	free(revoked->serial.ptr);
	free(revoked);
}

/**
 * Destroy a CDP entry
 */
static void cdp_destroy(x509_cdp_t *this)
{
	free(this->uri);
	DESTROY_IF(this->issuer);
	free(this);
}

METHOD(certificate_t, destroy, void,
	private_x509_crl_t *this)
{
	if (ref_put(&this->ref))
	{
		this->revoked->destroy_function(this->revoked, (void*)revoked_destroy);
		this->crl_uris->destroy_function(this->crl_uris, (void*)cdp_destroy);
		DESTROY_IF(this->issuer);
		free(this->authKeyIdentifier.ptr);
		free(this->encoding.ptr);
		if (this->generated)
		{
			free(this->crlNumber.ptr);
			free(this->baseCrlNumber.ptr);
			free(this->signature.ptr);
			free(this->tbsCertList.ptr);
		}
		free(this);
	}
}

/**
 * create an empty but initialized X.509 crl
 */
static private_x509_crl_t* create_empty(void)
{
	private_x509_crl_t *this;

	INIT(this,
		.public = {
			.crl = {
				.certificate = {
					.get_type = _get_type,
					.get_subject = _get_issuer,
					.get_issuer = _get_issuer,
					.has_subject = _has_issuer,
					.has_issuer = _has_issuer,
					.issued_by = _issued_by,
					.get_public_key = _get_public_key,
					.get_validity = _get_validity,
					.get_encoding = _get_encoding,
					.equals = _equals,
					.get_ref = _get_ref,
					.destroy = _destroy,
				},
				.get_serial = _get_serial,
				.get_authKeyIdentifier = _get_authKeyIdentifier,
				.is_delta_crl = _is_delta_crl,
				.create_delta_crl_uri_enumerator = _create_delta_crl_uri_enumerator,
				.create_enumerator = _create_enumerator,
			},
		},
		.revoked = linked_list_create(),
		.crl_uris = linked_list_create(),
		.ref = 1,
	);
	return this;
}

/**
 * See header.
 */
x509_crl_t *x509_crl_load(certificate_type_t type, va_list args)
{
	chunk_t blob = chunk_empty;

	while (TRUE)
	{
		switch (va_arg(args, builder_part_t))
		{
			case BUILD_BLOB_ASN1_DER:
				blob = va_arg(args, chunk_t);
				continue;
			case BUILD_END:
				break;
			default:
				return NULL;
		}
		break;
	}
	if (blob.ptr)
	{
		private_x509_crl_t *crl = create_empty();

		crl->encoding = chunk_clone(blob);
		if (parse(crl))
		{
			return &crl->public;
		}
		destroy(crl);
	}
	return NULL;
};

/**
 * Read certificate status from enumerator, copy to crl
 */
static void read_revoked(private_x509_crl_t *crl, enumerator_t *enumerator)
{
	revoked_t *revoked;
	chunk_t serial;
	time_t date;
	crl_reason_t reason;

	while (enumerator->enumerate(enumerator, &serial, &date, &reason))
	{
		INIT(revoked,
			.serial = chunk_clone(serial),
			.date = date,
			.reason = reason,
		);
		crl->revoked->insert_last(crl->revoked, revoked);
	}
}

/**
 * Generate CRL encoding, sign CRL
 */
static bool generate(private_x509_crl_t *this, certificate_t *cert,
					 private_key_t *key, hash_algorithm_t digest_alg)
{
	chunk_t extensions = chunk_empty, certList = chunk_empty, serial;
	chunk_t crlDistributionPoints = chunk_empty, baseCrlNumber = chunk_empty;
	enumerator_t *enumerator;
	crl_reason_t reason;
	time_t date;
	x509_t *x509;

	x509 = (x509_t*)cert;

	this->issuer = cert->get_subject(cert);
	this->issuer = this->issuer->clone(this->issuer);

	this->authKeyIdentifier = chunk_clone(x509->get_subjectKeyIdentifier(x509));

	/* select signature scheme */
	this->algorithm = hasher_signature_algorithm_to_oid(digest_alg,
														key->get_type(key));
	if (this->algorithm == OID_UNKNOWN)
	{
		return FALSE;
	}

	enumerator = create_enumerator(this);
	while (enumerator->enumerate(enumerator, &serial, &date, &reason))
	{
		chunk_t revoked, entry_ext = chunk_empty;

		if (reason != CRL_REASON_UNSPECIFIED)
		{
			entry_ext = asn1_wrap(ASN1_SEQUENCE, "m",
							asn1_wrap(ASN1_SEQUENCE, "mm",
								asn1_build_known_oid(OID_CRL_REASON_CODE),
								asn1_wrap(ASN1_OCTET_STRING, "m",
									asn1_wrap(ASN1_ENUMERATED, "c",
										chunk_from_chars(reason)))));
		}
		revoked = asn1_wrap(ASN1_SEQUENCE, "mmm",
							asn1_integer("c", serial),
							asn1_from_time(&date, ASN1_UTCTIME),
							entry_ext);
		certList = chunk_cat("mm", certList, revoked);
	}
	enumerator->destroy(enumerator);

	crlDistributionPoints = x509_build_crlDistributionPoints(this->crl_uris,
															 OID_FRESHEST_CRL);

	if (this->baseCrlNumber.len)
	{
		baseCrlNumber =  asn1_wrap(ASN1_SEQUENCE, "mmm",
							asn1_build_known_oid(OID_DELTA_CRL_INDICATOR),
							asn1_wrap(ASN1_BOOLEAN, "c",
								chunk_from_chars(0xFF)),
							asn1_wrap(ASN1_OCTET_STRING, "m",
								asn1_integer("c", this->baseCrlNumber)));
	}

	extensions = asn1_wrap(ASN1_CONTEXT_C_0, "m",
					asn1_wrap(ASN1_SEQUENCE, "mmmm",
						asn1_wrap(ASN1_SEQUENCE, "mm",
							asn1_build_known_oid(OID_AUTHORITY_KEY_ID),
							asn1_wrap(ASN1_OCTET_STRING, "m",
								asn1_wrap(ASN1_SEQUENCE, "m",
									asn1_wrap(ASN1_CONTEXT_S_0, "c",
											  this->authKeyIdentifier)))),
						asn1_wrap(ASN1_SEQUENCE, "mm",
							asn1_build_known_oid(OID_CRL_NUMBER),
							asn1_wrap(ASN1_OCTET_STRING, "m",
								asn1_integer("c", this->crlNumber))),
						crlDistributionPoints, baseCrlNumber));

	this->tbsCertList = asn1_wrap(ASN1_SEQUENCE, "cmcmmmm",
							ASN1_INTEGER_1,
							asn1_algorithmIdentifier(this->algorithm),
							this->issuer->get_encoding(this->issuer),
							asn1_from_time(&this->thisUpdate, ASN1_UTCTIME),
							asn1_from_time(&this->nextUpdate, ASN1_UTCTIME),
							asn1_wrap(ASN1_SEQUENCE, "m", certList),
							extensions);

	if (!key->sign(key, signature_scheme_from_oid(this->algorithm),
				   this->tbsCertList, &this->signature))
	{
		return FALSE;
	}
	this->encoding = asn1_wrap(ASN1_SEQUENCE, "cmm",
							this->tbsCertList,
							asn1_algorithmIdentifier(this->algorithm),
							asn1_bitstring("c", this->signature));
	return TRUE;
}

/**
 * See header.
 */
x509_crl_t *x509_crl_gen(certificate_type_t type, va_list args)
{
	hash_algorithm_t digest_alg = HASH_SHA1;
	private_x509_crl_t *crl;
	certificate_t *cert = NULL;
	private_key_t *key = NULL;

	crl = create_empty();
	crl->generated = TRUE;
	while (TRUE)
	{
		builder_part_t part = va_arg(args, builder_part_t);

		switch (part)
		{
			case BUILD_SIGNING_KEY:
				key = va_arg(args, private_key_t*);
				continue;
			case BUILD_SIGNING_CERT:
				cert = va_arg(args, certificate_t*);
				continue;
			case BUILD_NOT_BEFORE_TIME:
				crl->thisUpdate = va_arg(args, time_t);
				continue;
			case BUILD_NOT_AFTER_TIME:
				crl->nextUpdate = va_arg(args, time_t);
				continue;
			case BUILD_SERIAL:
				crl->crlNumber = va_arg(args, chunk_t);
				crl->crlNumber = chunk_clone(crl->crlNumber);
				continue;
			case BUILD_DIGEST_ALG:
				digest_alg = va_arg(args, int);
				continue;
			case BUILD_REVOKED_ENUMERATOR:
				read_revoked(crl, va_arg(args, enumerator_t*));
				continue;
			case BUILD_BASE_CRL:
				crl->baseCrlNumber = va_arg(args, chunk_t);
				crl->baseCrlNumber = chunk_clone(crl->baseCrlNumber);
				break;
			case BUILD_CRL_DISTRIBUTION_POINTS:
			{
				enumerator_t *enumerator;
				linked_list_t *list;
				x509_cdp_t *in, *cdp;

				list = va_arg(args, linked_list_t*);
				enumerator = list->create_enumerator(list);
				while (enumerator->enumerate(enumerator, &in))
				{
					INIT(cdp,
						.uri = strdup(in->uri),
						.issuer = in->issuer ? in->issuer->clone(in->issuer) : NULL,
					);
					crl->crl_uris->insert_last(crl->crl_uris, cdp);
				}
				enumerator->destroy(enumerator);
				continue;
			}
			case BUILD_END:
				break;
			default:
				destroy(crl);
				return NULL;
		}
		break;
	}

	if (key && cert && cert->get_type(cert) == CERT_X509 &&
		generate(crl, cert, key, digest_alg))
	{
		return &crl->public;
	}
	destroy(crl);
	return NULL;
}