GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libcrypto/crypto/../../libssl/src/crypto/ts/ts_rsp_verify.c Lines: 0 266 0.0 %
Date: 2016-12-06 Branches: 0 192 0.0 %

Line Branch Exec Source
1
/* $OpenBSD: ts_rsp_verify.c,v 1.16 2015/07/19 18:25:59 miod Exp $ */
2
/* Written by Zoltan Glozik (zglozik@stones.com) for the OpenSSL
3
 * project 2002.
4
 */
5
/* ====================================================================
6
 * Copyright (c) 2006 The OpenSSL Project.  All rights reserved.
7
 *
8
 * Redistribution and use in source and binary forms, with or without
9
 * modification, are permitted provided that the following conditions
10
 * are met:
11
 *
12
 * 1. Redistributions of source code must retain the above copyright
13
 *    notice, this list of conditions and the following disclaimer.
14
 *
15
 * 2. Redistributions in binary form must reproduce the above copyright
16
 *    notice, this list of conditions and the following disclaimer in
17
 *    the documentation and/or other materials provided with the
18
 *    distribution.
19
 *
20
 * 3. All advertising materials mentioning features or use of this
21
 *    software must display the following acknowledgment:
22
 *    "This product includes software developed by the OpenSSL Project
23
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24
 *
25
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26
 *    endorse or promote products derived from this software without
27
 *    prior written permission. For written permission, please contact
28
 *    licensing@OpenSSL.org.
29
 *
30
 * 5. Products derived from this software may not be called "OpenSSL"
31
 *    nor may "OpenSSL" appear in their names without prior written
32
 *    permission of the OpenSSL Project.
33
 *
34
 * 6. Redistributions of any form whatsoever must retain the following
35
 *    acknowledgment:
36
 *    "This product includes software developed by the OpenSSL Project
37
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38
 *
39
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50
 * OF THE POSSIBILITY OF SUCH DAMAGE.
51
 * ====================================================================
52
 *
53
 * This product includes cryptographic software written by Eric Young
54
 * (eay@cryptsoft.com).  This product includes software written by Tim
55
 * Hudson (tjh@cryptsoft.com).
56
 *
57
 */
58
59
#include <stdio.h>
60
#include <string.h>
61
62
#include <openssl/err.h>
63
#include <openssl/objects.h>
64
#include <openssl/pkcs7.h>
65
#include <openssl/ts.h>
66
67
/* Private function declarations. */
68
69
static int TS_verify_cert(X509_STORE *store, STACK_OF(X509) *untrusted,
70
    X509 *signer, STACK_OF(X509) **chain);
71
static int TS_check_signing_certs(PKCS7_SIGNER_INFO *si, STACK_OF(X509) *chain);
72
static ESS_SIGNING_CERT *ESS_get_signing_cert(PKCS7_SIGNER_INFO *si);
73
static int TS_find_cert(STACK_OF(ESS_CERT_ID) *cert_ids, X509 *cert);
74
static int TS_issuer_serial_cmp(ESS_ISSUER_SERIAL *is, X509_CINF *cinfo);
75
static int int_TS_RESP_verify_token(TS_VERIFY_CTX *ctx,
76
    PKCS7 *token, TS_TST_INFO *tst_info);
77
static int TS_check_status_info(TS_RESP *response);
78
static char *TS_get_status_text(STACK_OF(ASN1_UTF8STRING) *text);
79
static int TS_check_policy(ASN1_OBJECT *req_oid, TS_TST_INFO *tst_info);
80
static int TS_compute_imprint(BIO *data, TS_TST_INFO *tst_info,
81
    X509_ALGOR **md_alg,
82
    unsigned char **imprint, unsigned *imprint_len);
83
static int TS_check_imprints(X509_ALGOR *algor_a,
84
    unsigned char *imprint_a, unsigned len_a,
85
    TS_TST_INFO *tst_info);
86
static int TS_check_nonces(const ASN1_INTEGER *a, TS_TST_INFO *tst_info);
87
static int TS_check_signer_name(GENERAL_NAME *tsa_name, X509 *signer);
88
static int TS_find_name(STACK_OF(GENERAL_NAME) *gen_names, GENERAL_NAME *name);
89
90
/*
91
 * Local mapping between response codes and descriptions.
92
 * Don't forget to change TS_STATUS_BUF_SIZE when modifying
93
 * the elements of this array.
94
 */
95
static const char *TS_status_text[] = {
96
	"granted",
97
	"grantedWithMods",
98
	"rejection",
99
	"waiting",
100
	"revocationWarning",
101
	"revocationNotification"
102
};
103
104
#define TS_STATUS_TEXT_SIZE	(sizeof(TS_status_text)/sizeof(*TS_status_text))
105
106
/*
107
 * This must be greater or equal to the sum of the strings in TS_status_text
108
 * plus the number of its elements.
109
 */
110
#define TS_STATUS_BUF_SIZE	256
111
112
static struct {
113
	int code;
114
	const char *text;
115
} TS_failure_info[] = {
116
	{ TS_INFO_BAD_ALG, "badAlg" },
117
	{ TS_INFO_BAD_REQUEST, "badRequest" },
118
	{ TS_INFO_BAD_DATA_FORMAT, "badDataFormat" },
119
	{ TS_INFO_TIME_NOT_AVAILABLE, "timeNotAvailable" },
120
	{ TS_INFO_UNACCEPTED_POLICY, "unacceptedPolicy" },
121
	{ TS_INFO_UNACCEPTED_EXTENSION, "unacceptedExtension" },
122
	{ TS_INFO_ADD_INFO_NOT_AVAILABLE, "addInfoNotAvailable" },
123
	{ TS_INFO_SYSTEM_FAILURE, "systemFailure" }
124
};
125
126
#define TS_FAILURE_INFO_SIZE	(sizeof(TS_failure_info) / \
127
				sizeof(*TS_failure_info))
128
129
/* Functions for verifying a signed TS_TST_INFO structure. */
130
131
/*
132
 * This function carries out the following tasks:
133
 *	- Checks if there is one and only one signer.
134
 *	- Search for the signing certificate in 'certs' and in the response.
135
 *	- Check the extended key usage and key usage fields of the signer
136
 *	certificate (done by the path validation).
137
 *	- Build and validate the certificate path.
138
 *	- Check if the certificate path meets the requirements of the
139
 *	SigningCertificate ESS signed attribute.
140
 *	- Verify the signature value.
141
 *	- Returns the signer certificate in 'signer', if 'signer' is not NULL.
142
 */
143
int
144
TS_RESP_verify_signature(PKCS7 *token, STACK_OF(X509) *certs,
145
    X509_STORE *store, X509 **signer_out)
146
{
147
	STACK_OF(PKCS7_SIGNER_INFO) *sinfos = NULL;
148
	PKCS7_SIGNER_INFO *si;
149
	STACK_OF(X509) *signers = NULL;
150
	X509	*signer;
151
	STACK_OF(X509) *chain = NULL;
152
	char	buf[4096];
153
	int	i, j = 0, ret = 0;
154
	BIO	*p7bio = NULL;
155
156
	/* Some sanity checks first. */
157
	if (!token) {
158
		TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_INVALID_NULL_POINTER);
159
		goto err;
160
	}
161
162
	/* Check for the correct content type */
163
	if (!PKCS7_type_is_signed(token)) {
164
		TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_WRONG_CONTENT_TYPE);
165
		goto err;
166
	}
167
168
	/* Check if there is one and only one signer. */
169
	sinfos = PKCS7_get_signer_info(token);
170
	if (!sinfos || sk_PKCS7_SIGNER_INFO_num(sinfos) != 1) {
171
		TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE,
172
		    TS_R_THERE_MUST_BE_ONE_SIGNER);
173
		goto err;
174
	}
175
	si = sk_PKCS7_SIGNER_INFO_value(sinfos, 0);
176
177
	/* Check for no content: no data to verify signature. */
178
	if (PKCS7_get_detached(token)) {
179
		TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_NO_CONTENT);
180
		goto err;
181
	}
182
183
	/* Get hold of the signer certificate, search only internal
184
	   certificates if it was requested. */
185
	signers = PKCS7_get0_signers(token, certs, 0);
186
	if (!signers || sk_X509_num(signers) != 1)
187
		goto err;
188
	signer = sk_X509_value(signers, 0);
189
190
	/* Now verify the certificate. */
191
	if (!TS_verify_cert(store, certs, signer, &chain))
192
		goto err;
193
194
	/* Check if the signer certificate is consistent with the
195
	   ESS extension. */
196
	if (!TS_check_signing_certs(si, chain))
197
		goto err;
198
199
	/* Creating the message digest. */
200
	p7bio = PKCS7_dataInit(token, NULL);
201
202
	/* We now have to 'read' from p7bio to calculate digests etc. */
203
	while ((i = BIO_read(p7bio, buf, sizeof(buf))) > 0)
204
		;
205
206
	/* Verifying the signature. */
207
	j = PKCS7_signatureVerify(p7bio, token, si, signer);
208
	if (j <= 0) {
209
		TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_SIGNATURE_FAILURE);
210
		goto err;
211
	}
212
213
	/* Return the signer certificate if needed. */
214
	if (signer_out) {
215
		*signer_out = signer;
216
		CRYPTO_add(&signer->references, 1, CRYPTO_LOCK_X509);
217
	}
218
219
	ret = 1;
220
221
err:
222
	BIO_free_all(p7bio);
223
	sk_X509_pop_free(chain, X509_free);
224
	sk_X509_free(signers);
225
226
	return ret;
227
}
228
229
/*
230
 * The certificate chain is returned in chain. Caller is responsible for
231
 * freeing the vector.
232
 */
233
static int
234
TS_verify_cert(X509_STORE *store, STACK_OF(X509) *untrusted, X509 *signer,
235
    STACK_OF(X509) **chain)
236
{
237
	X509_STORE_CTX cert_ctx;
238
	int i;
239
	int ret = 0;
240
241
	/* chain is an out argument. */
242
	*chain = NULL;
243
	if (X509_STORE_CTX_init(&cert_ctx, store, signer, untrusted) == 0) {
244
		TSerr(TS_F_TS_VERIFY_CERT, ERR_R_X509_LIB);
245
		goto err;
246
	}
247
	X509_STORE_CTX_set_purpose(&cert_ctx, X509_PURPOSE_TIMESTAMP_SIGN);
248
	i = X509_verify_cert(&cert_ctx);
249
	if (i <= 0) {
250
		int j = X509_STORE_CTX_get_error(&cert_ctx);
251
252
		TSerr(TS_F_TS_VERIFY_CERT, TS_R_CERTIFICATE_VERIFY_ERROR);
253
		ERR_asprintf_error_data("Verify error:%s",
254
		    X509_verify_cert_error_string(j));
255
		goto err;
256
	} else {
257
		/* Get a copy of the certificate chain. */
258
		*chain = X509_STORE_CTX_get1_chain(&cert_ctx);
259
		ret = 1;
260
	}
261
262
err:
263
	X509_STORE_CTX_cleanup(&cert_ctx);
264
265
	return ret;
266
}
267
268
static int
269
TS_check_signing_certs(PKCS7_SIGNER_INFO *si, STACK_OF(X509) *chain)
270
{
271
	ESS_SIGNING_CERT *ss = ESS_get_signing_cert(si);
272
	STACK_OF(ESS_CERT_ID) *cert_ids = NULL;
273
	X509 *cert;
274
	int i = 0;
275
	int ret = 0;
276
277
	if (!ss)
278
		goto err;
279
	cert_ids = ss->cert_ids;
280
	/* The signer certificate must be the first in cert_ids. */
281
	cert = sk_X509_value(chain, 0);
282
	if (TS_find_cert(cert_ids, cert) != 0)
283
		goto err;
284
285
	/* Check the other certificates of the chain if there are more
286
	   than one certificate ids in cert_ids. */
287
	if (sk_ESS_CERT_ID_num(cert_ids) > 1) {
288
		/* All the certificates of the chain must be in cert_ids. */
289
		for (i = 1; i < sk_X509_num(chain); ++i) {
290
			cert = sk_X509_value(chain, i);
291
			if (TS_find_cert(cert_ids, cert) < 0)
292
				goto err;
293
		}
294
	}
295
	ret = 1;
296
297
err:
298
	if (!ret)
299
		TSerr(TS_F_TS_CHECK_SIGNING_CERTS,
300
		    TS_R_ESS_SIGNING_CERTIFICATE_ERROR);
301
	ESS_SIGNING_CERT_free(ss);
302
	return ret;
303
}
304
305
static ESS_SIGNING_CERT *
306
ESS_get_signing_cert(PKCS7_SIGNER_INFO *si)
307
{
308
	ASN1_TYPE *attr;
309
	const unsigned char *p;
310
311
	attr = PKCS7_get_signed_attribute(si,
312
	    NID_id_smime_aa_signingCertificate);
313
	if (!attr)
314
		return NULL;
315
	if (attr->type != V_ASN1_SEQUENCE)
316
		return NULL;
317
	p = attr->value.sequence->data;
318
	return d2i_ESS_SIGNING_CERT(NULL, &p, attr->value.sequence->length);
319
}
320
321
/* Returns < 0 if certificate is not found, certificate index otherwise. */
322
static int
323
TS_find_cert(STACK_OF(ESS_CERT_ID) *cert_ids, X509 *cert)
324
{
325
	int i;
326
327
	if (!cert_ids || !cert)
328
		return -1;
329
330
	/* Recompute SHA1 hash of certificate if necessary (side effect). */
331
	X509_check_purpose(cert, -1, 0);
332
333
	/* Look for cert in the cert_ids vector. */
334
	for (i = 0; i < sk_ESS_CERT_ID_num(cert_ids); ++i) {
335
		ESS_CERT_ID *cid = sk_ESS_CERT_ID_value(cert_ids, i);
336
337
		/* Check the SHA-1 hash first. */
338
		if (cid->hash->length == sizeof(cert->sha1_hash) &&
339
		    !memcmp(cid->hash->data, cert->sha1_hash,
340
			sizeof(cert->sha1_hash))) {
341
			/* Check the issuer/serial as well if specified. */
342
			ESS_ISSUER_SERIAL *is = cid->issuer_serial;
343
			if (!is || !TS_issuer_serial_cmp(is, cert->cert_info))
344
				return i;
345
		}
346
	}
347
348
	return -1;
349
}
350
351
static int
352
TS_issuer_serial_cmp(ESS_ISSUER_SERIAL *is, X509_CINF *cinfo)
353
{
354
	GENERAL_NAME *issuer;
355
356
	if (!is || !cinfo || sk_GENERAL_NAME_num(is->issuer) != 1)
357
		return -1;
358
359
	/* Check the issuer first. It must be a directory name. */
360
	issuer = sk_GENERAL_NAME_value(is->issuer, 0);
361
	if (issuer->type != GEN_DIRNAME ||
362
	    X509_NAME_cmp(issuer->d.dirn, cinfo->issuer))
363
		return -1;
364
365
	/* Check the serial number, too. */
366
	if (ASN1_INTEGER_cmp(is->serial, cinfo->serialNumber))
367
		return -1;
368
369
	return 0;
370
}
371
372
/*
373
 * Verifies whether 'response' contains a valid response with regards
374
 * to the settings of the context:
375
 *	- Gives an error message if the TS_TST_INFO is not present.
376
 *	- Calls _TS_RESP_verify_token to verify the token content.
377
 */
378
int
379
TS_RESP_verify_response(TS_VERIFY_CTX *ctx, TS_RESP *response)
380
{
381
	PKCS7 *token = TS_RESP_get_token(response);
382
	TS_TST_INFO *tst_info = TS_RESP_get_tst_info(response);
383
	int ret = 0;
384
385
	/* Check if we have a successful TS_TST_INFO object in place. */
386
	if (!TS_check_status_info(response))
387
		goto err;
388
389
	/* Check the contents of the time stamp token. */
390
	if (!int_TS_RESP_verify_token(ctx, token, tst_info))
391
		goto err;
392
393
	ret = 1;
394
395
err:
396
	return ret;
397
}
398
399
/*
400
 * Tries to extract a TS_TST_INFO structure from the PKCS7 token and
401
 * calls the internal int_TS_RESP_verify_token function for verifying it.
402
 */
403
int
404
TS_RESP_verify_token(TS_VERIFY_CTX *ctx, PKCS7 *token)
405
{
406
	TS_TST_INFO *tst_info = PKCS7_to_TS_TST_INFO(token);
407
	int ret = 0;
408
409
	if (tst_info) {
410
		ret = int_TS_RESP_verify_token(ctx, token, tst_info);
411
		TS_TST_INFO_free(tst_info);
412
	}
413
	return ret;
414
}
415
416
/*
417
 * Verifies whether the 'token' contains a valid time stamp token
418
 * with regards to the settings of the context. Only those checks are
419
 * carried out that are specified in the context:
420
 *	- Verifies the signature of the TS_TST_INFO.
421
 *	- Checks the version number of the response.
422
 *	- Check if the requested and returned policies math.
423
 *	- Check if the message imprints are the same.
424
 *	- Check if the nonces are the same.
425
 *	- Check if the TSA name matches the signer.
426
 *	- Check if the TSA name is the expected TSA.
427
 */
428
static int
429
int_TS_RESP_verify_token(TS_VERIFY_CTX *ctx, PKCS7 *token,
430
    TS_TST_INFO *tst_info)
431
{
432
	X509 *signer = NULL;
433
	GENERAL_NAME *tsa_name = TS_TST_INFO_get_tsa(tst_info);
434
	X509_ALGOR *md_alg = NULL;
435
	unsigned char *imprint = NULL;
436
	unsigned imprint_len = 0;
437
	int ret = 0;
438
439
	/* Verify the signature. */
440
	if ((ctx->flags & TS_VFY_SIGNATURE) &&
441
	    !TS_RESP_verify_signature(token, ctx->certs, ctx->store, &signer))
442
		goto err;
443
444
	/* Check version number of response. */
445
	if ((ctx->flags & TS_VFY_VERSION) &&
446
	    TS_TST_INFO_get_version(tst_info) != 1) {
447
		TSerr(TS_F_INT_TS_RESP_VERIFY_TOKEN, TS_R_UNSUPPORTED_VERSION);
448
		goto err;
449
	}
450
451
	/* Check policies. */
452
	if ((ctx->flags & TS_VFY_POLICY) &&
453
	    !TS_check_policy(ctx->policy, tst_info))
454
		goto err;
455
456
	/* Check message imprints. */
457
	if ((ctx->flags & TS_VFY_IMPRINT) &&
458
	    !TS_check_imprints(ctx->md_alg, ctx->imprint, ctx->imprint_len,
459
		tst_info))
460
		goto err;
461
462
	/* Compute and check message imprints. */
463
	if ((ctx->flags & TS_VFY_DATA) &&
464
	    (!TS_compute_imprint(ctx->data, tst_info,
465
	    &md_alg, &imprint, &imprint_len) ||
466
	    !TS_check_imprints(md_alg, imprint, imprint_len, tst_info)))
467
		goto err;
468
469
	/* Check nonces. */
470
	if ((ctx->flags & TS_VFY_NONCE) &&
471
	    !TS_check_nonces(ctx->nonce, tst_info))
472
		goto err;
473
474
	/* Check whether TSA name and signer certificate match. */
475
	if ((ctx->flags & TS_VFY_SIGNER) &&
476
	    tsa_name && !TS_check_signer_name(tsa_name, signer)) {
477
		TSerr(TS_F_INT_TS_RESP_VERIFY_TOKEN, TS_R_TSA_NAME_MISMATCH);
478
		goto err;
479
	}
480
481
	/* Check whether the TSA is the expected one. */
482
	if ((ctx->flags & TS_VFY_TSA_NAME) &&
483
	    !TS_check_signer_name(ctx->tsa_name, signer)) {
484
		TSerr(TS_F_INT_TS_RESP_VERIFY_TOKEN, TS_R_TSA_UNTRUSTED);
485
		goto err;
486
	}
487
488
	ret = 1;
489
490
err:
491
	X509_free(signer);
492
	X509_ALGOR_free(md_alg);
493
	free(imprint);
494
	return ret;
495
}
496
497
static int
498
TS_check_status_info(TS_RESP *response)
499
{
500
	TS_STATUS_INFO *info = TS_RESP_get_status_info(response);
501
	long status = ASN1_INTEGER_get(info->status);
502
	const char *status_text = NULL;
503
	char *embedded_status_text = NULL;
504
	char failure_text[TS_STATUS_BUF_SIZE] = "";
505
506
	/* Check if everything went fine. */
507
	if (status == 0 || status == 1)
508
		return 1;
509
510
	/* There was an error, get the description in status_text. */
511
	if (0 <= status && status < (long)TS_STATUS_TEXT_SIZE)
512
		status_text = TS_status_text[status];
513
	else
514
		status_text = "unknown code";
515
516
	/* Set the embedded_status_text to the returned description. */
517
	if (sk_ASN1_UTF8STRING_num(info->text) > 0 &&
518
	    !(embedded_status_text = TS_get_status_text(info->text)))
519
		return 0;
520
521
	/* Filling in failure_text with the failure information. */
522
	if (info->failure_info) {
523
		int i;
524
		int first = 1;
525
		for (i = 0; i < (int)TS_FAILURE_INFO_SIZE; ++i) {
526
			if (ASN1_BIT_STRING_get_bit(info->failure_info,
527
			    TS_failure_info[i].code)) {
528
				if (!first)
529
					strlcat(failure_text, ",",
530
					    TS_STATUS_BUF_SIZE);
531
				else
532
					first = 0;
533
				strlcat(failure_text, TS_failure_info[i].text,
534
				    TS_STATUS_BUF_SIZE);
535
			}
536
		}
537
	}
538
	if (failure_text[0] == '\0')
539
		strlcpy(failure_text, "unspecified", TS_STATUS_BUF_SIZE);
540
541
	/* Making up the error string. */
542
	TSerr(TS_F_TS_CHECK_STATUS_INFO, TS_R_NO_TIME_STAMP_TOKEN);
543
	ERR_asprintf_error_data
544
	    ("status code: %s, status text: %s, failure codes: %s",
545
	    status_text,
546
	    embedded_status_text ? embedded_status_text : "unspecified",
547
	    failure_text);
548
	free(embedded_status_text);
549
550
	return 0;
551
}
552
553
static char *
554
TS_get_status_text(STACK_OF(ASN1_UTF8STRING) *text)
555
{
556
	int i;
557
	unsigned int length = 0;
558
	char *result = NULL;
559
560
	/* Determine length first. */
561
	for (i = 0; i < sk_ASN1_UTF8STRING_num(text); ++i) {
562
		ASN1_UTF8STRING *current = sk_ASN1_UTF8STRING_value(text, i);
563
		length += ASN1_STRING_length(current);
564
		length += 1;	/* separator character */
565
	}
566
	/* Allocate memory (closing '\0' included). */
567
	if (!(result = malloc(length))) {
568
		TSerr(TS_F_TS_GET_STATUS_TEXT, ERR_R_MALLOC_FAILURE);
569
		return NULL;
570
	}
571
	/* Concatenate the descriptions. */
572
	result[0] = '\0';
573
	for (i = 0; i < sk_ASN1_UTF8STRING_num(text); ++i) {
574
		ASN1_UTF8STRING *current = sk_ASN1_UTF8STRING_value(text, i);
575
		if (i > 0)
576
			strlcat(result, "/", length);
577
		strlcat(result, (const char *)ASN1_STRING_data(current), length);
578
	}
579
	return result;
580
}
581
582
static int
583
TS_check_policy(ASN1_OBJECT *req_oid, TS_TST_INFO *tst_info)
584
{
585
	ASN1_OBJECT *resp_oid = TS_TST_INFO_get_policy_id(tst_info);
586
587
	if (OBJ_cmp(req_oid, resp_oid) != 0) {
588
		TSerr(TS_F_TS_CHECK_POLICY, TS_R_POLICY_MISMATCH);
589
		return 0;
590
	}
591
592
	return 1;
593
}
594
595
static int
596
TS_compute_imprint(BIO *data, TS_TST_INFO *tst_info, X509_ALGOR **md_alg,
597
    unsigned char **imprint, unsigned *imprint_len)
598
{
599
	TS_MSG_IMPRINT *msg_imprint = TS_TST_INFO_get_msg_imprint(tst_info);
600
	X509_ALGOR *md_alg_resp = TS_MSG_IMPRINT_get_algo(msg_imprint);
601
	const EVP_MD *md;
602
	EVP_MD_CTX md_ctx;
603
	unsigned char buffer[4096];
604
	int length;
605
606
	*md_alg = NULL;
607
	*imprint = NULL;
608
609
	/* Return the MD algorithm of the response. */
610
	if (!(*md_alg = X509_ALGOR_dup(md_alg_resp)))
611
		goto err;
612
613
	/* Getting the MD object. */
614
	if (!(md = EVP_get_digestbyobj((*md_alg)->algorithm))) {
615
		TSerr(TS_F_TS_COMPUTE_IMPRINT, TS_R_UNSUPPORTED_MD_ALGORITHM);
616
		goto err;
617
	}
618
619
	/* Compute message digest. */
620
	length = EVP_MD_size(md);
621
	if (length < 0)
622
		goto err;
623
	*imprint_len = length;
624
	if (!(*imprint = malloc(*imprint_len))) {
625
		TSerr(TS_F_TS_COMPUTE_IMPRINT, ERR_R_MALLOC_FAILURE);
626
		goto err;
627
	}
628
629
	if (!EVP_DigestInit(&md_ctx, md))
630
		goto err;
631
	while ((length = BIO_read(data, buffer, sizeof(buffer))) > 0) {
632
		if (!EVP_DigestUpdate(&md_ctx, buffer, length))
633
			goto err;
634
	}
635
	if (!EVP_DigestFinal(&md_ctx, *imprint, NULL))
636
		goto err;
637
638
	return 1;
639
640
err:
641
	X509_ALGOR_free(*md_alg);
642
	free(*imprint);
643
	*imprint = NULL;
644
	*imprint_len = 0;
645
	return 0;
646
}
647
648
static int
649
TS_check_imprints(X509_ALGOR *algor_a, unsigned char *imprint_a, unsigned len_a,
650
    TS_TST_INFO *tst_info)
651
{
652
	TS_MSG_IMPRINT *b = TS_TST_INFO_get_msg_imprint(tst_info);
653
	X509_ALGOR *algor_b = TS_MSG_IMPRINT_get_algo(b);
654
	int ret = 0;
655
656
	/* algor_a is optional. */
657
	if (algor_a) {
658
		/* Compare algorithm OIDs. */
659
		if (OBJ_cmp(algor_a->algorithm, algor_b->algorithm))
660
			goto err;
661
662
		/* The parameter must be NULL in both. */
663
		if ((algor_a->parameter &&
664
		    ASN1_TYPE_get(algor_a->parameter) != V_ASN1_NULL) ||
665
		    (algor_b->parameter &&
666
		    ASN1_TYPE_get(algor_b->parameter) != V_ASN1_NULL))
667
			goto err;
668
	}
669
670
	/* Compare octet strings. */
671
	ret = len_a == (unsigned) ASN1_STRING_length(b->hashed_msg) &&
672
	    memcmp(imprint_a, ASN1_STRING_data(b->hashed_msg), len_a) == 0;
673
674
err:
675
	if (!ret)
676
		TSerr(TS_F_TS_CHECK_IMPRINTS, TS_R_MESSAGE_IMPRINT_MISMATCH);
677
	return ret;
678
}
679
680
static int
681
TS_check_nonces(const ASN1_INTEGER *a, TS_TST_INFO *tst_info)
682
{
683
	const ASN1_INTEGER *b = TS_TST_INFO_get_nonce(tst_info);
684
685
	/* Error if nonce is missing. */
686
	if (!b) {
687
		TSerr(TS_F_TS_CHECK_NONCES, TS_R_NONCE_NOT_RETURNED);
688
		return 0;
689
	}
690
691
	/* No error if a nonce is returned without being requested. */
692
	if (ASN1_INTEGER_cmp(a, b) != 0) {
693
		TSerr(TS_F_TS_CHECK_NONCES, TS_R_NONCE_MISMATCH);
694
		return 0;
695
	}
696
697
	return 1;
698
}
699
700
/* Check if the specified TSA name matches either the subject
701
   or one of the subject alternative names of the TSA certificate. */
702
static int
703
TS_check_signer_name(GENERAL_NAME *tsa_name, X509 *signer)
704
{
705
	STACK_OF(GENERAL_NAME) *gen_names = NULL;
706
	int idx = -1;
707
	int found = 0;
708
709
	if (signer == NULL)
710
		return 0;
711
712
	/* Check the subject name first. */
713
	if (tsa_name->type == GEN_DIRNAME &&
714
	    X509_name_cmp(tsa_name->d.dirn, signer->cert_info->subject) == 0)
715
		return 1;
716
717
	/* Check all the alternative names. */
718
	gen_names = X509_get_ext_d2i(signer, NID_subject_alt_name,
719
	    NULL, &idx);
720
	while (gen_names != NULL &&
721
	    !(found = (TS_find_name(gen_names, tsa_name) >= 0))) {
722
		/* Get the next subject alternative name,
723
		   although there should be no more than one. */
724
		GENERAL_NAMES_free(gen_names);
725
		gen_names = X509_get_ext_d2i(signer, NID_subject_alt_name,
726
		    NULL, &idx);
727
	}
728
	if (gen_names)
729
		GENERAL_NAMES_free(gen_names);
730
731
	return found;
732
}
733
734
/* Returns 1 if name is in gen_names, 0 otherwise. */
735
static int
736
TS_find_name(STACK_OF(GENERAL_NAME) *gen_names, GENERAL_NAME *name)
737
{
738
	int i, found;
739
	for (i = 0, found = 0; !found && i < sk_GENERAL_NAME_num(gen_names);
740
	    ++i) {
741
		GENERAL_NAME *current = sk_GENERAL_NAME_value(gen_names, i);
742
		found = GENERAL_NAME_cmp(current, name) == 0;
743
	}
744
	return found ? i - 1 : -1;
745
}