xref: /dragonfly/crypto/libressl/crypto/ts/ts_rsp_sign.c (revision 961e30ea7dc61d1112b778ea4981eac68129fb86)
1 /* $OpenBSD: ts_rsp_sign.c,v 1.29 2022/07/24 20:02:04 tb 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 <sys/time.h>
60 
61 #include <string.h>
62 
63 #include <openssl/err.h>
64 #include <openssl/objects.h>
65 #include <openssl/pkcs7.h>
66 #include <openssl/ts.h>
67 
68 #include "evp_locl.h"
69 #include "ts_local.h"
70 #include "x509_lcl.h"
71 
72 /* Private function declarations. */
73 
74 static ASN1_INTEGER *def_serial_cb(struct TS_resp_ctx *, void *);
75 static int def_time_cb(struct TS_resp_ctx *, void *, time_t *sec, long *usec);
76 static int def_extension_cb(struct TS_resp_ctx *, X509_EXTENSION *, void *);
77 
78 static void TS_RESP_CTX_init(TS_RESP_CTX *ctx);
79 static void TS_RESP_CTX_cleanup(TS_RESP_CTX *ctx);
80 static int TS_RESP_check_request(TS_RESP_CTX *ctx);
81 static ASN1_OBJECT *TS_RESP_get_policy(TS_RESP_CTX *ctx);
82 static TS_TST_INFO *TS_RESP_create_tst_info(TS_RESP_CTX *ctx,
83     ASN1_OBJECT *policy);
84 static int TS_RESP_process_extensions(TS_RESP_CTX *ctx);
85 static int TS_RESP_sign(TS_RESP_CTX *ctx);
86 
87 static ESS_SIGNING_CERT *ESS_SIGNING_CERT_new_init(X509 *signcert,
88     STACK_OF(X509) *certs);
89 static ESS_CERT_ID *ESS_CERT_ID_new_init(X509 *cert, int issuer_needed);
90 static int TS_TST_INFO_content_new(PKCS7 *p7);
91 static int ESS_add_signing_cert(PKCS7_SIGNER_INFO *si, ESS_SIGNING_CERT *sc);
92 
93 static ASN1_GENERALIZEDTIME *TS_RESP_set_genTime_with_precision(
94     ASN1_GENERALIZEDTIME *, time_t, long, unsigned);
95 
96 /* Default callbacks for response generation. */
97 
98 static ASN1_INTEGER *
def_serial_cb(struct TS_resp_ctx * ctx,void * data)99 def_serial_cb(struct TS_resp_ctx *ctx, void *data)
100 {
101           ASN1_INTEGER *serial = ASN1_INTEGER_new();
102 
103           if (!serial)
104                     goto err;
105           if (!ASN1_INTEGER_set(serial, 1))
106                     goto err;
107           return serial;
108 
109 err:
110           TSerror(ERR_R_MALLOC_FAILURE);
111           TS_RESP_CTX_set_status_info(ctx, TS_STATUS_REJECTION,
112               "Error during serial number generation.");
113           return NULL;
114 }
115 
116 /* Use the gettimeofday function call. */
117 static int
def_time_cb(struct TS_resp_ctx * ctx,void * data,time_t * sec,long * usec)118 def_time_cb(struct TS_resp_ctx *ctx, void *data, time_t *sec, long *usec)
119 {
120           struct timeval tv;
121 
122           if (gettimeofday(&tv, NULL) != 0) {
123                     TSerror(TS_R_TIME_SYSCALL_ERROR);
124                     TS_RESP_CTX_set_status_info(ctx, TS_STATUS_REJECTION,
125                         "Time is not available.");
126                     TS_RESP_CTX_add_failure_info(ctx, TS_INFO_TIME_NOT_AVAILABLE);
127                     return 0;
128           }
129           /* Return time to caller. */
130           *sec = tv.tv_sec;
131           *usec = tv.tv_usec;
132 
133           return 1;
134 }
135 
136 static int
def_extension_cb(struct TS_resp_ctx * ctx,X509_EXTENSION * ext,void * data)137 def_extension_cb(struct TS_resp_ctx *ctx, X509_EXTENSION *ext, void *data)
138 {
139           /* No extensions are processed here. */
140           TS_RESP_CTX_set_status_info(ctx, TS_STATUS_REJECTION,
141               "Unsupported extension.");
142           TS_RESP_CTX_add_failure_info(ctx, TS_INFO_UNACCEPTED_EXTENSION);
143           return 0;
144 }
145 
146 void
TS_RESP_CTX_set_time_cb(TS_RESP_CTX * ctx,TS_time_cb cb,void * data)147 TS_RESP_CTX_set_time_cb(TS_RESP_CTX *ctx, TS_time_cb cb, void *data)
148 {
149           ctx->time_cb = cb;
150           ctx->time_cb_data = data;
151 }
152 
153 /* TS_RESP_CTX management functions. */
154 
155 TS_RESP_CTX *
TS_RESP_CTX_new(void)156 TS_RESP_CTX_new(void)
157 {
158           TS_RESP_CTX *ctx;
159 
160           if (!(ctx = calloc(1, sizeof(TS_RESP_CTX)))) {
161                     TSerror(ERR_R_MALLOC_FAILURE);
162                     return NULL;
163           }
164 
165           /* Setting default callbacks. */
166           ctx->serial_cb = def_serial_cb;
167           ctx->time_cb = def_time_cb;
168           ctx->extension_cb = def_extension_cb;
169 
170           return ctx;
171 }
172 
173 void
TS_RESP_CTX_free(TS_RESP_CTX * ctx)174 TS_RESP_CTX_free(TS_RESP_CTX *ctx)
175 {
176           if (!ctx)
177                     return;
178 
179           X509_free(ctx->signer_cert);
180           EVP_PKEY_free(ctx->signer_key);
181           sk_X509_pop_free(ctx->certs, X509_free);
182           sk_ASN1_OBJECT_pop_free(ctx->policies, ASN1_OBJECT_free);
183           ASN1_OBJECT_free(ctx->default_policy);
184           sk_EVP_MD_free(ctx->mds);     /* No EVP_MD_free method exists. */
185           ASN1_INTEGER_free(ctx->seconds);
186           ASN1_INTEGER_free(ctx->millis);
187           ASN1_INTEGER_free(ctx->micros);
188           free(ctx);
189 }
190 
191 int
TS_RESP_CTX_set_signer_cert(TS_RESP_CTX * ctx,X509 * signer)192 TS_RESP_CTX_set_signer_cert(TS_RESP_CTX *ctx, X509 *signer)
193 {
194           if (X509_check_purpose(signer, X509_PURPOSE_TIMESTAMP_SIGN, 0) != 1) {
195                     TSerror(TS_R_INVALID_SIGNER_CERTIFICATE_PURPOSE);
196                     return 0;
197           }
198           X509_free(ctx->signer_cert);
199           ctx->signer_cert = signer;
200           CRYPTO_add(&ctx->signer_cert->references, +1, CRYPTO_LOCK_X509);
201           return 1;
202 }
203 
204 int
TS_RESP_CTX_set_signer_key(TS_RESP_CTX * ctx,EVP_PKEY * key)205 TS_RESP_CTX_set_signer_key(TS_RESP_CTX *ctx, EVP_PKEY *key)
206 {
207           EVP_PKEY_free(ctx->signer_key);
208           ctx->signer_key = key;
209           CRYPTO_add(&ctx->signer_key->references, +1, CRYPTO_LOCK_EVP_PKEY);
210 
211           return 1;
212 }
213 
214 int
TS_RESP_CTX_set_def_policy(TS_RESP_CTX * ctx,const ASN1_OBJECT * def_policy)215 TS_RESP_CTX_set_def_policy(TS_RESP_CTX *ctx, const ASN1_OBJECT *def_policy)
216 {
217           if (ctx->default_policy)
218                     ASN1_OBJECT_free(ctx->default_policy);
219           if (!(ctx->default_policy = OBJ_dup(def_policy)))
220                     goto err;
221           return 1;
222 
223 err:
224           TSerror(ERR_R_MALLOC_FAILURE);
225           return 0;
226 }
227 
228 int
TS_RESP_CTX_set_certs(TS_RESP_CTX * ctx,STACK_OF (X509)* certs)229 TS_RESP_CTX_set_certs(TS_RESP_CTX *ctx, STACK_OF(X509) *certs)
230 {
231           int i;
232 
233           if (ctx->certs) {
234                     sk_X509_pop_free(ctx->certs, X509_free);
235                     ctx->certs = NULL;
236           }
237           if (!certs)
238                     return 1;
239           if (!(ctx->certs = sk_X509_dup(certs))) {
240                     TSerror(ERR_R_MALLOC_FAILURE);
241                     return 0;
242           }
243           for (i = 0; i < sk_X509_num(ctx->certs); ++i) {
244                     X509 *cert = sk_X509_value(ctx->certs, i);
245                     CRYPTO_add(&cert->references, +1, CRYPTO_LOCK_X509);
246           }
247 
248           return 1;
249 }
250 
251 int
TS_RESP_CTX_add_policy(TS_RESP_CTX * ctx,const ASN1_OBJECT * policy)252 TS_RESP_CTX_add_policy(TS_RESP_CTX *ctx, const ASN1_OBJECT *policy)
253 {
254           ASN1_OBJECT *copy = NULL;
255 
256           /* Create new policy stack if necessary. */
257           if (!ctx->policies && !(ctx->policies = sk_ASN1_OBJECT_new_null()))
258                     goto err;
259           if (!(copy = OBJ_dup(policy)))
260                     goto err;
261           if (!sk_ASN1_OBJECT_push(ctx->policies, copy))
262                     goto err;
263 
264           return 1;
265 
266 err:
267           TSerror(ERR_R_MALLOC_FAILURE);
268           ASN1_OBJECT_free(copy);
269           return 0;
270 }
271 
272 int
TS_RESP_CTX_add_md(TS_RESP_CTX * ctx,const EVP_MD * md)273 TS_RESP_CTX_add_md(TS_RESP_CTX *ctx, const EVP_MD *md)
274 {
275           /* Create new md stack if necessary. */
276           if (!ctx->mds && !(ctx->mds = sk_EVP_MD_new_null()))
277                     goto err;
278           /* Add the shared md, no copy needed. */
279           if (!sk_EVP_MD_push(ctx->mds, (EVP_MD *)md))
280                     goto err;
281 
282           return 1;
283 
284 err:
285           TSerror(ERR_R_MALLOC_FAILURE);
286           return 0;
287 }
288 
289 #define TS_RESP_CTX_accuracy_free(ctx)            \
290           ASN1_INTEGER_free(ctx->seconds);        \
291           ctx->seconds = NULL;                              \
292           ASN1_INTEGER_free(ctx->millis);                   \
293           ctx->millis = NULL;                     \
294           ASN1_INTEGER_free(ctx->micros);                   \
295           ctx->micros = NULL;
296 
297 int
TS_RESP_CTX_set_accuracy(TS_RESP_CTX * ctx,int secs,int millis,int micros)298 TS_RESP_CTX_set_accuracy(TS_RESP_CTX *ctx, int secs, int millis, int micros)
299 {
300           TS_RESP_CTX_accuracy_free(ctx);
301           if (secs && (!(ctx->seconds = ASN1_INTEGER_new()) ||
302               !ASN1_INTEGER_set(ctx->seconds, secs)))
303                     goto err;
304           if (millis && (!(ctx->millis = ASN1_INTEGER_new()) ||
305               !ASN1_INTEGER_set(ctx->millis, millis)))
306                     goto err;
307           if (micros && (!(ctx->micros = ASN1_INTEGER_new()) ||
308               !ASN1_INTEGER_set(ctx->micros, micros)))
309                     goto err;
310 
311           return 1;
312 
313 err:
314           TS_RESP_CTX_accuracy_free(ctx);
315           TSerror(ERR_R_MALLOC_FAILURE);
316           return 0;
317 }
318 
319 void
TS_RESP_CTX_add_flags(TS_RESP_CTX * ctx,int flags)320 TS_RESP_CTX_add_flags(TS_RESP_CTX *ctx, int flags)
321 {
322           ctx->flags |= flags;
323 }
324 
325 void
TS_RESP_CTX_set_serial_cb(TS_RESP_CTX * ctx,TS_serial_cb cb,void * data)326 TS_RESP_CTX_set_serial_cb(TS_RESP_CTX *ctx, TS_serial_cb cb, void *data)
327 {
328           ctx->serial_cb = cb;
329           ctx->serial_cb_data = data;
330 }
331 
332 void
TS_RESP_CTX_set_extension_cb(TS_RESP_CTX * ctx,TS_extension_cb cb,void * data)333 TS_RESP_CTX_set_extension_cb(TS_RESP_CTX *ctx, TS_extension_cb cb, void *data)
334 {
335           ctx->extension_cb = cb;
336           ctx->extension_cb_data = data;
337 }
338 
339 int
TS_RESP_CTX_set_status_info(TS_RESP_CTX * ctx,int status,const char * text)340 TS_RESP_CTX_set_status_info(TS_RESP_CTX *ctx, int status, const char *text)
341 {
342           TS_STATUS_INFO *si = NULL;
343           ASN1_UTF8STRING *utf8_text = NULL;
344           int ret = 0;
345 
346           if (!(si = TS_STATUS_INFO_new()))
347                     goto err;
348           if (!ASN1_INTEGER_set(si->status, status))
349                     goto err;
350           if (text) {
351                     if (!(utf8_text = ASN1_UTF8STRING_new()) ||
352                         !ASN1_STRING_set(utf8_text, text, strlen(text)))
353                               goto err;
354                     if (!si->text && !(si->text = sk_ASN1_UTF8STRING_new_null()))
355                               goto err;
356                     if (!sk_ASN1_UTF8STRING_push(si->text, utf8_text))
357                               goto err;
358                     utf8_text = NULL;   /* Ownership is lost. */
359           }
360           if (!TS_RESP_set_status_info(ctx->response, si))
361                     goto err;
362           ret = 1;
363 
364 err:
365           if (!ret)
366                     TSerror(ERR_R_MALLOC_FAILURE);
367           TS_STATUS_INFO_free(si);
368           ASN1_UTF8STRING_free(utf8_text);
369           return ret;
370 }
371 
372 int
TS_RESP_CTX_set_status_info_cond(TS_RESP_CTX * ctx,int status,const char * text)373 TS_RESP_CTX_set_status_info_cond(TS_RESP_CTX *ctx, int status, const char *text)
374 {
375           int ret = 1;
376           TS_STATUS_INFO *si = TS_RESP_get_status_info(ctx->response);
377 
378           if (ASN1_INTEGER_get(si->status) == TS_STATUS_GRANTED) {
379                     /* Status has not been set, set it now. */
380                     ret = TS_RESP_CTX_set_status_info(ctx, status, text);
381           }
382           return ret;
383 }
384 
385 int
TS_RESP_CTX_add_failure_info(TS_RESP_CTX * ctx,int failure)386 TS_RESP_CTX_add_failure_info(TS_RESP_CTX *ctx, int failure)
387 {
388           TS_STATUS_INFO *si = TS_RESP_get_status_info(ctx->response);
389 
390           if (!si->failure_info && !(si->failure_info = ASN1_BIT_STRING_new()))
391                     goto err;
392           if (!ASN1_BIT_STRING_set_bit(si->failure_info, failure, 1))
393                     goto err;
394           return 1;
395 
396 err:
397           TSerror(ERR_R_MALLOC_FAILURE);
398           return 0;
399 }
400 
401 TS_REQ *
TS_RESP_CTX_get_request(TS_RESP_CTX * ctx)402 TS_RESP_CTX_get_request(TS_RESP_CTX *ctx)
403 {
404           return ctx->request;
405 }
406 
407 TS_TST_INFO *
TS_RESP_CTX_get_tst_info(TS_RESP_CTX * ctx)408 TS_RESP_CTX_get_tst_info(TS_RESP_CTX *ctx)
409 {
410           return ctx->tst_info;
411 }
412 
413 int
TS_RESP_CTX_set_clock_precision_digits(TS_RESP_CTX * ctx,unsigned precision)414 TS_RESP_CTX_set_clock_precision_digits(TS_RESP_CTX *ctx, unsigned precision)
415 {
416           if (precision > TS_MAX_CLOCK_PRECISION_DIGITS)
417                     return 0;
418           ctx->clock_precision_digits = precision;
419           return 1;
420 }
421 
422 /* Main entry method of the response generation. */
423 TS_RESP *
TS_RESP_create_response(TS_RESP_CTX * ctx,BIO * req_bio)424 TS_RESP_create_response(TS_RESP_CTX *ctx, BIO *req_bio)
425 {
426           ASN1_OBJECT *policy;
427           TS_RESP *response;
428           int result = 0;
429 
430           TS_RESP_CTX_init(ctx);
431 
432           /* Creating the response object. */
433           if (!(ctx->response = TS_RESP_new())) {
434                     TSerror(ERR_R_MALLOC_FAILURE);
435                     goto end;
436           }
437 
438           /* Parsing DER request. */
439           if (!(ctx->request = d2i_TS_REQ_bio(req_bio, NULL))) {
440                     TS_RESP_CTX_set_status_info(ctx, TS_STATUS_REJECTION,
441                         "Bad request format or "
442                         "system error.");
443                     TS_RESP_CTX_add_failure_info(ctx, TS_INFO_BAD_DATA_FORMAT);
444                     goto end;
445           }
446 
447           /* Setting default status info. */
448           if (!TS_RESP_CTX_set_status_info(ctx, TS_STATUS_GRANTED, NULL))
449                     goto end;
450 
451           /* Checking the request format. */
452           if (!TS_RESP_check_request(ctx))
453                     goto end;
454 
455           /* Checking acceptable policies. */
456           if (!(policy = TS_RESP_get_policy(ctx)))
457                     goto end;
458 
459           /* Creating the TS_TST_INFO object. */
460           if (!(ctx->tst_info = TS_RESP_create_tst_info(ctx, policy)))
461                     goto end;
462 
463           /* Processing extensions. */
464           if (!TS_RESP_process_extensions(ctx))
465                     goto end;
466 
467           /* Generating the signature. */
468           if (!TS_RESP_sign(ctx))
469                     goto end;
470 
471           /* Everything was successful. */
472           result = 1;
473 
474 end:
475           if (!result) {
476                     TSerror(TS_R_RESPONSE_SETUP_ERROR);
477                     if (ctx->response != NULL) {
478                               if (TS_RESP_CTX_set_status_info_cond(ctx,
479                                   TS_STATUS_REJECTION, "Error during response "
480                                   "generation.") == 0) {
481                                         TS_RESP_free(ctx->response);
482                                         ctx->response = NULL;
483                               }
484                     }
485           }
486           response = ctx->response;
487           ctx->response = NULL;         /* Ownership will be returned to caller. */
488           TS_RESP_CTX_cleanup(ctx);
489           return response;
490 }
491 
492 /* Initializes the variable part of the context. */
493 static void
TS_RESP_CTX_init(TS_RESP_CTX * ctx)494 TS_RESP_CTX_init(TS_RESP_CTX *ctx)
495 {
496           ctx->request = NULL;
497           ctx->response = NULL;
498           ctx->tst_info = NULL;
499 }
500 
501 /* Cleans up the variable part of the context. */
502 static void
TS_RESP_CTX_cleanup(TS_RESP_CTX * ctx)503 TS_RESP_CTX_cleanup(TS_RESP_CTX *ctx)
504 {
505           TS_REQ_free(ctx->request);
506           ctx->request = NULL;
507           TS_RESP_free(ctx->response);
508           ctx->response = NULL;
509           TS_TST_INFO_free(ctx->tst_info);
510           ctx->tst_info = NULL;
511 }
512 
513 /* Checks the format and content of the request. */
514 static int
TS_RESP_check_request(TS_RESP_CTX * ctx)515 TS_RESP_check_request(TS_RESP_CTX *ctx)
516 {
517           TS_REQ *request = ctx->request;
518           TS_MSG_IMPRINT *msg_imprint;
519           X509_ALGOR *md_alg;
520           int md_alg_id;
521           const ASN1_OCTET_STRING *digest;
522           EVP_MD *md = NULL;
523           int i;
524 
525           /* Checking request version. */
526           if (TS_REQ_get_version(request) != 1) {
527                     TS_RESP_CTX_set_status_info(ctx, TS_STATUS_REJECTION,
528                         "Bad request version.");
529                     TS_RESP_CTX_add_failure_info(ctx, TS_INFO_BAD_REQUEST);
530                     return 0;
531           }
532 
533           /* Checking message digest algorithm. */
534           msg_imprint = TS_REQ_get_msg_imprint(request);
535           md_alg = TS_MSG_IMPRINT_get_algo(msg_imprint);
536           md_alg_id = OBJ_obj2nid(md_alg->algorithm);
537           for (i = 0; !md && i < sk_EVP_MD_num(ctx->mds); ++i) {
538                     EVP_MD *current_md = sk_EVP_MD_value(ctx->mds, i);
539                     if (md_alg_id == EVP_MD_type(current_md))
540                               md = current_md;
541           }
542           if (!md) {
543                     TS_RESP_CTX_set_status_info(ctx, TS_STATUS_REJECTION,
544                         "Message digest algorithm is "
545                         "not supported.");
546                     TS_RESP_CTX_add_failure_info(ctx, TS_INFO_BAD_ALG);
547                     return 0;
548           }
549 
550           /* No message digest takes parameter. */
551           if (md_alg->parameter &&
552               ASN1_TYPE_get(md_alg->parameter) != V_ASN1_NULL) {
553                     TS_RESP_CTX_set_status_info(ctx, TS_STATUS_REJECTION,
554                         "Superfluous message digest "
555                         "parameter.");
556                     TS_RESP_CTX_add_failure_info(ctx, TS_INFO_BAD_ALG);
557                     return 0;
558           }
559           /* Checking message digest size. */
560           digest = TS_MSG_IMPRINT_get_msg(msg_imprint);
561           if (digest->length != EVP_MD_size(md)) {
562                     TS_RESP_CTX_set_status_info(ctx, TS_STATUS_REJECTION,
563                         "Bad message digest.");
564                     TS_RESP_CTX_add_failure_info(ctx, TS_INFO_BAD_DATA_FORMAT);
565                     return 0;
566           }
567 
568           return 1;
569 }
570 
571 /* Returns the TSA policy based on the requested and acceptable policies. */
572 static ASN1_OBJECT *
TS_RESP_get_policy(TS_RESP_CTX * ctx)573 TS_RESP_get_policy(TS_RESP_CTX *ctx)
574 {
575           ASN1_OBJECT *requested = TS_REQ_get_policy_id(ctx->request);
576           ASN1_OBJECT *policy = NULL;
577           int i;
578 
579           if (ctx->default_policy == NULL) {
580                     TSerror(TS_R_INVALID_NULL_POINTER);
581                     return NULL;
582           }
583           /* Return the default policy if none is requested or the default is
584              requested. */
585           if (!requested || !OBJ_cmp(requested, ctx->default_policy))
586                     policy = ctx->default_policy;
587 
588           /* Check if the policy is acceptable. */
589           for (i = 0; !policy && i < sk_ASN1_OBJECT_num(ctx->policies); ++i) {
590                     ASN1_OBJECT *current = sk_ASN1_OBJECT_value(ctx->policies, i);
591                     if (!OBJ_cmp(requested, current))
592                               policy = current;
593           }
594           if (!policy) {
595                     TSerror(TS_R_UNACCEPTABLE_POLICY);
596                     TS_RESP_CTX_set_status_info(ctx, TS_STATUS_REJECTION,
597                         "Requested policy is not "
598                         "supported.");
599                     TS_RESP_CTX_add_failure_info(ctx, TS_INFO_UNACCEPTED_POLICY);
600           }
601           return policy;
602 }
603 
604 /* Creates the TS_TST_INFO object based on the settings of the context. */
605 static TS_TST_INFO *
TS_RESP_create_tst_info(TS_RESP_CTX * ctx,ASN1_OBJECT * policy)606 TS_RESP_create_tst_info(TS_RESP_CTX *ctx, ASN1_OBJECT *policy)
607 {
608           int result = 0;
609           TS_TST_INFO *tst_info = NULL;
610           ASN1_INTEGER *serial = NULL;
611           ASN1_GENERALIZEDTIME *asn1_time = NULL;
612           time_t sec;
613           long usec;
614           TS_ACCURACY *accuracy = NULL;
615           const ASN1_INTEGER *nonce;
616           GENERAL_NAME *tsa_name = NULL;
617 
618           if (!(tst_info = TS_TST_INFO_new()))
619                     goto end;
620           if (!TS_TST_INFO_set_version(tst_info, 1))
621                     goto end;
622           if (!TS_TST_INFO_set_policy_id(tst_info, policy))
623                     goto end;
624           if (!TS_TST_INFO_set_msg_imprint(tst_info, ctx->request->msg_imprint))
625                     goto end;
626           if (!(serial = (*ctx->serial_cb)(ctx, ctx->serial_cb_data)) ||
627               !TS_TST_INFO_set_serial(tst_info, serial))
628                     goto end;
629           if (!(*ctx->time_cb)(ctx, ctx->time_cb_data, &sec, &usec) ||
630               !(asn1_time = TS_RESP_set_genTime_with_precision(NULL, sec, usec,
631               ctx->clock_precision_digits)) ||
632               !TS_TST_INFO_set_time(tst_info, asn1_time))
633                     goto end;
634 
635           /* Setting accuracy if needed. */
636           if ((ctx->seconds || ctx->millis || ctx->micros) &&
637               !(accuracy = TS_ACCURACY_new()))
638                     goto end;
639 
640           if (ctx->seconds && !TS_ACCURACY_set_seconds(accuracy, ctx->seconds))
641                     goto end;
642           if (ctx->millis && !TS_ACCURACY_set_millis(accuracy, ctx->millis))
643                     goto end;
644           if (ctx->micros && !TS_ACCURACY_set_micros(accuracy, ctx->micros))
645                     goto end;
646           if (accuracy && !TS_TST_INFO_set_accuracy(tst_info, accuracy))
647                     goto end;
648 
649           /* Setting ordering. */
650           if ((ctx->flags & TS_ORDERING) &&
651               !TS_TST_INFO_set_ordering(tst_info, 1))
652                     goto end;
653 
654           /* Setting nonce if needed. */
655           if ((nonce = TS_REQ_get_nonce(ctx->request)) != NULL &&
656               !TS_TST_INFO_set_nonce(tst_info, nonce))
657                     goto end;
658 
659           /* Setting TSA name to subject of signer certificate. */
660           if (ctx->flags & TS_TSA_NAME) {
661                     if (!(tsa_name = GENERAL_NAME_new()))
662                               goto end;
663                     tsa_name->type = GEN_DIRNAME;
664                     tsa_name->d.dirn =
665                         X509_NAME_dup(X509_get_subject_name(ctx->signer_cert));
666                     if (!tsa_name->d.dirn)
667                               goto end;
668                     if (!TS_TST_INFO_set_tsa(tst_info, tsa_name))
669                               goto end;
670           }
671 
672           result = 1;
673 
674 end:
675           if (!result) {
676                     TS_TST_INFO_free(tst_info);
677                     tst_info = NULL;
678                     TSerror(TS_R_TST_INFO_SETUP_ERROR);
679                     TS_RESP_CTX_set_status_info_cond(ctx, TS_STATUS_REJECTION,
680                         "Error during TSTInfo "
681                         "generation.");
682           }
683           GENERAL_NAME_free(tsa_name);
684           TS_ACCURACY_free(accuracy);
685           ASN1_GENERALIZEDTIME_free(asn1_time);
686           ASN1_INTEGER_free(serial);
687 
688           return tst_info;
689 }
690 
691 /* Processing the extensions of the request. */
692 static int
TS_RESP_process_extensions(TS_RESP_CTX * ctx)693 TS_RESP_process_extensions(TS_RESP_CTX *ctx)
694 {
695           STACK_OF(X509_EXTENSION) *exts = TS_REQ_get_exts(ctx->request);
696           int i;
697           int ok = 1;
698 
699           for (i = 0; ok && i < sk_X509_EXTENSION_num(exts); ++i) {
700                     X509_EXTENSION *ext = sk_X509_EXTENSION_value(exts, i);
701                     /* XXXXX The last argument was previously
702                        (void *)ctx->extension_cb, but ISO C doesn't permit
703                        converting a function pointer to void *.  For lack of
704                        better information, I'm placing a NULL there instead.
705                        The callback can pick its own address out from the ctx
706                        anyway...
707                     */
708                     ok = (*ctx->extension_cb)(ctx, ext, NULL);
709           }
710 
711           return ok;
712 }
713 
714 /* Functions for signing the TS_TST_INFO structure of the context. */
715 static int
TS_RESP_sign(TS_RESP_CTX * ctx)716 TS_RESP_sign(TS_RESP_CTX *ctx)
717 {
718           int ret = 0;
719           PKCS7 *p7 = NULL;
720           PKCS7_SIGNER_INFO *si;
721           STACK_OF(X509) *certs;        /* Certificates to include in sc. */
722           ESS_SIGNING_CERT *sc = NULL;
723           ASN1_OBJECT *oid;
724           BIO *p7bio = NULL;
725           int i;
726 
727           /* Check if signcert and pkey match. */
728           if (!X509_check_private_key(ctx->signer_cert, ctx->signer_key)) {
729                     TSerror(TS_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
730                     goto err;
731           }
732 
733           /* Create a new PKCS7 signed object. */
734           if (!(p7 = PKCS7_new())) {
735                     TSerror(ERR_R_MALLOC_FAILURE);
736                     goto err;
737           }
738           if (!PKCS7_set_type(p7, NID_pkcs7_signed))
739                     goto err;
740 
741           /* Force SignedData version to be 3 instead of the default 1. */
742           if (!ASN1_INTEGER_set(p7->d.sign->version, 3))
743                     goto err;
744 
745           /* Add signer certificate and optional certificate chain. */
746           if (TS_REQ_get_cert_req(ctx->request)) {
747                     PKCS7_add_certificate(p7, ctx->signer_cert);
748                     if (ctx->certs) {
749                               for (i = 0; i < sk_X509_num(ctx->certs); ++i) {
750                                         X509 *cert = sk_X509_value(ctx->certs, i);
751                                         PKCS7_add_certificate(p7, cert);
752                               }
753                     }
754           }
755 
756           /* Add a new signer info. */
757           if (!(si = PKCS7_add_signature(p7, ctx->signer_cert,
758               ctx->signer_key, EVP_sha1()))) {
759                     TSerror(TS_R_PKCS7_ADD_SIGNATURE_ERROR);
760                     goto err;
761           }
762 
763           /* Add content type signed attribute to the signer info. */
764           oid = OBJ_nid2obj(NID_id_smime_ct_TSTInfo);
765           if (!PKCS7_add_signed_attribute(si, NID_pkcs9_contentType,
766               V_ASN1_OBJECT, oid)) {
767                     TSerror(TS_R_PKCS7_ADD_SIGNED_ATTR_ERROR);
768                     goto err;
769           }
770 
771           /* Create the ESS SigningCertificate attribute which contains
772              the signer certificate id and optionally the certificate chain. */
773           certs = ctx->flags & TS_ESS_CERT_ID_CHAIN ? ctx->certs : NULL;
774           if (!(sc = ESS_SIGNING_CERT_new_init(ctx->signer_cert, certs)))
775                     goto err;
776 
777           /* Add SigningCertificate signed attribute to the signer info. */
778           if (!ESS_add_signing_cert(si, sc)) {
779                     TSerror(TS_R_ESS_ADD_SIGNING_CERT_ERROR);
780                     goto err;
781           }
782 
783           /* Add a new empty NID_id_smime_ct_TSTInfo encapsulated content. */
784           if (!TS_TST_INFO_content_new(p7))
785                     goto err;
786 
787           /* Add the DER encoded tst_info to the PKCS7 structure. */
788           if (!(p7bio = PKCS7_dataInit(p7, NULL))) {
789                     TSerror(ERR_R_MALLOC_FAILURE);
790                     goto err;
791           }
792 
793           /* Convert tst_info to DER. */
794           if (!i2d_TS_TST_INFO_bio(p7bio, ctx->tst_info)) {
795                     TSerror(TS_R_TS_DATASIGN);
796                     goto err;
797           }
798 
799           /* Create the signature and add it to the signer info. */
800           if (!PKCS7_dataFinal(p7, p7bio)) {
801                     TSerror(TS_R_TS_DATASIGN);
802                     goto err;
803           }
804 
805           /* Set new PKCS7 and TST_INFO objects. */
806           TS_RESP_set_tst_info(ctx->response, p7, ctx->tst_info);
807           p7 = NULL;                    /* Ownership is lost. */
808           ctx->tst_info = NULL;         /* Ownership is lost. */
809 
810           ret = 1;
811 
812 err:
813           if (!ret)
814                     TS_RESP_CTX_set_status_info_cond(ctx, TS_STATUS_REJECTION,
815               "Error during signature "
816               "generation.");
817           BIO_free_all(p7bio);
818           ESS_SIGNING_CERT_free(sc);
819           PKCS7_free(p7);
820           return ret;
821 }
822 
823 static ESS_SIGNING_CERT *
ESS_SIGNING_CERT_new_init(X509 * signcert,STACK_OF (X509)* certs)824 ESS_SIGNING_CERT_new_init(X509 *signcert, STACK_OF(X509) *certs)
825 {
826           ESS_CERT_ID *cid;
827           ESS_SIGNING_CERT *sc = NULL;
828           int i;
829 
830           /* Creating the ESS_CERT_ID stack. */
831           if (!(sc = ESS_SIGNING_CERT_new()))
832                     goto err;
833           if (!sc->cert_ids && !(sc->cert_ids = sk_ESS_CERT_ID_new_null()))
834                     goto err;
835 
836           /* Adding the signing certificate id. */
837           if (!(cid = ESS_CERT_ID_new_init(signcert, 0)) ||
838               !sk_ESS_CERT_ID_push(sc->cert_ids, cid))
839                     goto err;
840           /* Adding the certificate chain ids. */
841           for (i = 0; i < sk_X509_num(certs); ++i) {
842                     X509 *cert = sk_X509_value(certs, i);
843                     if (!(cid = ESS_CERT_ID_new_init(cert, 1)) ||
844                         !sk_ESS_CERT_ID_push(sc->cert_ids, cid))
845                               goto err;
846           }
847 
848           return sc;
849 
850 err:
851           ESS_SIGNING_CERT_free(sc);
852           TSerror(ERR_R_MALLOC_FAILURE);
853           return NULL;
854 }
855 
856 static ESS_CERT_ID *
ESS_CERT_ID_new_init(X509 * cert,int issuer_needed)857 ESS_CERT_ID_new_init(X509 *cert, int issuer_needed)
858 {
859           ESS_CERT_ID *cid = NULL;
860           GENERAL_NAME *name = NULL;
861           unsigned char cert_hash[TS_HASH_LEN];
862 
863           /* Recompute SHA1 hash of certificate if necessary (side effect). */
864           X509_check_purpose(cert, -1, 0);
865 
866           if (!(cid = ESS_CERT_ID_new()))
867                     goto err;
868 
869           if (!X509_digest(cert, TS_HASH_EVP, cert_hash, NULL))
870                     goto err;
871 
872           if (!ASN1_OCTET_STRING_set(cid->hash, cert_hash, sizeof(cert_hash)))
873                     goto err;
874 
875           /* Setting the issuer/serial if requested. */
876           if (issuer_needed) {
877                     /* Creating issuer/serial structure. */
878                     if (!cid->issuer_serial &&
879                         !(cid->issuer_serial = ESS_ISSUER_SERIAL_new()))
880                               goto err;
881                     /* Creating general name from the certificate issuer. */
882                     if (!(name = GENERAL_NAME_new()))
883                               goto err;
884                     name->type = GEN_DIRNAME;
885                     if ((name->d.dirn = X509_NAME_dup(X509_get_issuer_name(cert))) == NULL)
886                               goto err;
887                     if (!sk_GENERAL_NAME_push(cid->issuer_serial->issuer, name))
888                               goto err;
889                     name = NULL;        /* Ownership is lost. */
890                     /* Setting the serial number. */
891                     ASN1_INTEGER_free(cid->issuer_serial->serial);
892                     if (!(cid->issuer_serial->serial =
893                         ASN1_INTEGER_dup(X509_get_serialNumber(cert))))
894                               goto err;
895           }
896 
897           return cid;
898 
899 err:
900           GENERAL_NAME_free(name);
901           ESS_CERT_ID_free(cid);
902           TSerror(ERR_R_MALLOC_FAILURE);
903           return NULL;
904 }
905 
906 static int
TS_TST_INFO_content_new(PKCS7 * p7)907 TS_TST_INFO_content_new(PKCS7 *p7)
908 {
909           PKCS7 *ret = NULL;
910           ASN1_OCTET_STRING *octet_string = NULL;
911 
912           /* Create new encapsulated NID_id_smime_ct_TSTInfo content. */
913           if (!(ret = PKCS7_new()))
914                     goto err;
915           if (!(ret->d.other = ASN1_TYPE_new()))
916                     goto err;
917           ret->type = OBJ_nid2obj(NID_id_smime_ct_TSTInfo);
918           if (!(octet_string = ASN1_OCTET_STRING_new()))
919                     goto err;
920           ASN1_TYPE_set(ret->d.other, V_ASN1_OCTET_STRING, octet_string);
921           octet_string = NULL;
922 
923           /* Add encapsulated content to signed PKCS7 structure. */
924           if (!PKCS7_set_content(p7, ret))
925                     goto err;
926 
927           return 1;
928 
929 err:
930           ASN1_OCTET_STRING_free(octet_string);
931           PKCS7_free(ret);
932           return 0;
933 }
934 
935 static int
ESS_add_signing_cert(PKCS7_SIGNER_INFO * si,ESS_SIGNING_CERT * sc)936 ESS_add_signing_cert(PKCS7_SIGNER_INFO *si, ESS_SIGNING_CERT *sc)
937 {
938           ASN1_STRING *seq = NULL;
939           unsigned char *p, *pp = NULL;
940           int len;
941 
942           len = i2d_ESS_SIGNING_CERT(sc, NULL);
943           if (!(pp = malloc(len))) {
944                     TSerror(ERR_R_MALLOC_FAILURE);
945                     goto err;
946           }
947           p = pp;
948           i2d_ESS_SIGNING_CERT(sc, &p);
949           if (!(seq = ASN1_STRING_new()) || !ASN1_STRING_set(seq, pp, len)) {
950                     TSerror(ERR_R_MALLOC_FAILURE);
951                     goto err;
952           }
953           free(pp);
954           pp = NULL;
955           return PKCS7_add_signed_attribute(si,
956               NID_id_smime_aa_signingCertificate, V_ASN1_SEQUENCE, seq);
957 
958 err:
959           ASN1_STRING_free(seq);
960           free(pp);
961 
962           return 0;
963 }
964 
965 
966 static ASN1_GENERALIZEDTIME *
TS_RESP_set_genTime_with_precision(ASN1_GENERALIZEDTIME * asn1_time,time_t sec,long usec,unsigned precision)967 TS_RESP_set_genTime_with_precision(ASN1_GENERALIZEDTIME *asn1_time,
968     time_t sec, long usec, unsigned precision)
969 {
970           struct tm *tm = NULL;
971           char genTime_str[17 + TS_MAX_CLOCK_PRECISION_DIGITS];
972           char usecstr[TS_MAX_CLOCK_PRECISION_DIGITS + 2];
973           char *p;
974           int rv;
975 
976           if (precision > TS_MAX_CLOCK_PRECISION_DIGITS)
977                     goto err;
978 
979           if (!(tm = gmtime(&sec)))
980                     goto err;
981 
982           /*
983            * Put "genTime_str" in GeneralizedTime format.  We work around the
984            * restrictions imposed by rfc3280 (i.e. "GeneralizedTime values MUST
985            * NOT include fractional seconds") and OpenSSL related functions to
986            * meet the rfc3161 requirement: "GeneralizedTime syntax can include
987            * fraction-of-second details".
988            */
989           if (precision > 0) {
990                     /* To make things a bit harder, X.690 | ISO/IEC 8825-1 provides
991                        the following restrictions for a DER-encoding, which OpenSSL
992                        (specifically ASN1_GENERALIZEDTIME_check() function) doesn't
993                        support:
994                        "The encoding MUST terminate with a "Z" (which means "Zulu"
995                        time). The decimal point element, if present, MUST be the
996                        point option ".". The fractional-seconds elements,
997                        if present, MUST omit all trailing 0's;
998                        if the elements correspond to 0, they MUST be wholly
999                        omitted, and the decimal point element also MUST be
1000                        omitted." */
1001                     (void) snprintf(usecstr, sizeof(usecstr), ".%06ld", usec);
1002                     /* truncate and trim trailing 0 */
1003                     usecstr[precision + 1] = '\0';
1004                     p = usecstr + strlen(usecstr) - 1;
1005                     while (p > usecstr && *p == '0')
1006                               *p-- = '\0';
1007                     /* if we've reached the beginning, delete the . too */
1008                     if (p == usecstr)
1009                               *p = '\0';
1010 
1011           } else {
1012                     /* empty */
1013                     usecstr[0] = '\0';
1014           }
1015           rv = snprintf(genTime_str, sizeof(genTime_str),
1016               "%04d%02d%02d%02d%02d%02d%sZ",
1017               tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
1018               tm->tm_hour, tm->tm_min, tm->tm_sec, usecstr);
1019           if (rv < 0 || rv >= sizeof(genTime_str))
1020                     goto err;
1021 
1022           /* Now call OpenSSL to check and set our genTime value */
1023           if (!asn1_time && !(asn1_time = ASN1_GENERALIZEDTIME_new()))
1024                     goto err;
1025           if (!ASN1_GENERALIZEDTIME_set_string(asn1_time, genTime_str)) {
1026                     ASN1_GENERALIZEDTIME_free(asn1_time);
1027                     goto err;
1028           }
1029 
1030           return asn1_time;
1031 
1032 err:
1033           TSerror(TS_R_COULD_NOT_SET_TIME);
1034           return NULL;
1035 }
1036