xref: /optee_os/lib/libmbedtls/mbedtls/library/x509.c (revision 817466cb476de705a8e3dabe1ef165fe27a18c2f)
1 /*
2  *  X.509 common functions for parsing and verification
3  *
4  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5  *  SPDX-License-Identifier: Apache-2.0
6  *
7  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
8  *  not use this file except in compliance with the License.
9  *  You may obtain a copy of the License at
10  *
11  *  http://www.apache.org/licenses/LICENSE-2.0
12  *
13  *  Unless required by applicable law or agreed to in writing, software
14  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16  *  See the License for the specific language governing permissions and
17  *  limitations under the License.
18  *
19  *  This file is part of mbed TLS (https://tls.mbed.org)
20  */
21 /*
22  *  The ITU-T X.509 standard defines a certificate format for PKI.
23  *
24  *  http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
25  *  http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
26  *  http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
27  *
28  *  http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
29  *  http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
30  */
31 
32 #if !defined(MBEDTLS_CONFIG_FILE)
33 #include "mbedtls/config.h"
34 #else
35 #include MBEDTLS_CONFIG_FILE
36 #endif
37 
38 #if defined(MBEDTLS_X509_USE_C)
39 
40 #include "mbedtls/x509.h"
41 #include "mbedtls/asn1.h"
42 #include "mbedtls/oid.h"
43 
44 #include <stdio.h>
45 #include <string.h>
46 
47 #if defined(MBEDTLS_PEM_PARSE_C)
48 #include "mbedtls/pem.h"
49 #endif
50 
51 #if defined(MBEDTLS_PLATFORM_C)
52 #include "mbedtls/platform.h"
53 #else
54 #include <stdio.h>
55 #include <stdlib.h>
56 #define mbedtls_free      free
57 #define mbedtls_calloc    calloc
58 #define mbedtls_printf    printf
59 #define mbedtls_snprintf  snprintf
60 #endif
61 
62 
63 #if defined(MBEDTLS_HAVE_TIME)
64 #include "mbedtls/platform_time.h"
65 #endif
66 
67 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
68 #include <windows.h>
69 #else
70 #include <time.h>
71 #endif
72 
73 #if defined(MBEDTLS_FS_IO)
74 #include <stdio.h>
75 #if !defined(_WIN32)
76 #include <sys/types.h>
77 #include <sys/stat.h>
78 #include <dirent.h>
79 #endif
80 #endif
81 
82 #define CHECK(code) if( ( ret = code ) != 0 ){ return( ret ); }
83 #define CHECK_RANGE(min, max, val) if( val < min || val > max ){ return( ret ); }
84 
85 /*
86  *  CertificateSerialNumber  ::=  INTEGER
87  */
88 int mbedtls_x509_get_serial( unsigned char **p, const unsigned char *end,
89                      mbedtls_x509_buf *serial )
90 {
91     int ret;
92 
93     if( ( end - *p ) < 1 )
94         return( MBEDTLS_ERR_X509_INVALID_SERIAL +
95                 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
96 
97     if( **p != ( MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_PRIMITIVE | 2 ) &&
98         **p !=   MBEDTLS_ASN1_INTEGER )
99         return( MBEDTLS_ERR_X509_INVALID_SERIAL +
100                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
101 
102     serial->tag = *(*p)++;
103 
104     if( ( ret = mbedtls_asn1_get_len( p, end, &serial->len ) ) != 0 )
105         return( MBEDTLS_ERR_X509_INVALID_SERIAL + ret );
106 
107     serial->p = *p;
108     *p += serial->len;
109 
110     return( 0 );
111 }
112 
113 /* Get an algorithm identifier without parameters (eg for signatures)
114  *
115  *  AlgorithmIdentifier  ::=  SEQUENCE  {
116  *       algorithm               OBJECT IDENTIFIER,
117  *       parameters              ANY DEFINED BY algorithm OPTIONAL  }
118  */
119 int mbedtls_x509_get_alg_null( unsigned char **p, const unsigned char *end,
120                        mbedtls_x509_buf *alg )
121 {
122     int ret;
123 
124     if( ( ret = mbedtls_asn1_get_alg_null( p, end, alg ) ) != 0 )
125         return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
126 
127     return( 0 );
128 }
129 
130 /*
131  * Parse an algorithm identifier with (optional) paramaters
132  */
133 int mbedtls_x509_get_alg( unsigned char **p, const unsigned char *end,
134                   mbedtls_x509_buf *alg, mbedtls_x509_buf *params )
135 {
136     int ret;
137 
138     if( ( ret = mbedtls_asn1_get_alg( p, end, alg, params ) ) != 0 )
139         return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
140 
141     return( 0 );
142 }
143 
144 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
145 /*
146  * HashAlgorithm ::= AlgorithmIdentifier
147  *
148  * AlgorithmIdentifier  ::=  SEQUENCE  {
149  *      algorithm               OBJECT IDENTIFIER,
150  *      parameters              ANY DEFINED BY algorithm OPTIONAL  }
151  *
152  * For HashAlgorithm, parameters MUST be NULL or absent.
153  */
154 static int x509_get_hash_alg( const mbedtls_x509_buf *alg, mbedtls_md_type_t *md_alg )
155 {
156     int ret;
157     unsigned char *p;
158     const unsigned char *end;
159     mbedtls_x509_buf md_oid;
160     size_t len;
161 
162     /* Make sure we got a SEQUENCE and setup bounds */
163     if( alg->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
164         return( MBEDTLS_ERR_X509_INVALID_ALG +
165                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
166 
167     p = (unsigned char *) alg->p;
168     end = p + alg->len;
169 
170     if( p >= end )
171         return( MBEDTLS_ERR_X509_INVALID_ALG +
172                 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
173 
174     /* Parse md_oid */
175     md_oid.tag = *p;
176 
177     if( ( ret = mbedtls_asn1_get_tag( &p, end, &md_oid.len, MBEDTLS_ASN1_OID ) ) != 0 )
178         return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
179 
180     md_oid.p = p;
181     p += md_oid.len;
182 
183     /* Get md_alg from md_oid */
184     if( ( ret = mbedtls_oid_get_md_alg( &md_oid, md_alg ) ) != 0 )
185         return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
186 
187     /* Make sure params is absent of NULL */
188     if( p == end )
189         return( 0 );
190 
191     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_NULL ) ) != 0 || len != 0 )
192         return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
193 
194     if( p != end )
195         return( MBEDTLS_ERR_X509_INVALID_ALG +
196                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
197 
198     return( 0 );
199 }
200 
201 /*
202  *    RSASSA-PSS-params  ::=  SEQUENCE  {
203  *       hashAlgorithm     [0] HashAlgorithm DEFAULT sha1Identifier,
204  *       maskGenAlgorithm  [1] MaskGenAlgorithm DEFAULT mgf1SHA1Identifier,
205  *       saltLength        [2] INTEGER DEFAULT 20,
206  *       trailerField      [3] INTEGER DEFAULT 1  }
207  *    -- Note that the tags in this Sequence are explicit.
208  *
209  * RFC 4055 (which defines use of RSASSA-PSS in PKIX) states that the value
210  * of trailerField MUST be 1, and PKCS#1 v2.2 doesn't even define any other
211  * option. Enfore this at parsing time.
212  */
213 int mbedtls_x509_get_rsassa_pss_params( const mbedtls_x509_buf *params,
214                                 mbedtls_md_type_t *md_alg, mbedtls_md_type_t *mgf_md,
215                                 int *salt_len )
216 {
217     int ret;
218     unsigned char *p;
219     const unsigned char *end, *end2;
220     size_t len;
221     mbedtls_x509_buf alg_id, alg_params;
222 
223     /* First set everything to defaults */
224     *md_alg = MBEDTLS_MD_SHA1;
225     *mgf_md = MBEDTLS_MD_SHA1;
226     *salt_len = 20;
227 
228     /* Make sure params is a SEQUENCE and setup bounds */
229     if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
230         return( MBEDTLS_ERR_X509_INVALID_ALG +
231                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
232 
233     p = (unsigned char *) params->p;
234     end = p + params->len;
235 
236     if( p == end )
237         return( 0 );
238 
239     /*
240      * HashAlgorithm
241      */
242     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
243                     MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) == 0 )
244     {
245         end2 = p + len;
246 
247         /* HashAlgorithm ::= AlgorithmIdentifier (without parameters) */
248         if( ( ret = mbedtls_x509_get_alg_null( &p, end2, &alg_id ) ) != 0 )
249             return( ret );
250 
251         if( ( ret = mbedtls_oid_get_md_alg( &alg_id, md_alg ) ) != 0 )
252             return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
253 
254         if( p != end2 )
255             return( MBEDTLS_ERR_X509_INVALID_ALG +
256                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
257     }
258     else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
259         return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
260 
261     if( p == end )
262         return( 0 );
263 
264     /*
265      * MaskGenAlgorithm
266      */
267     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
268                     MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 1 ) ) == 0 )
269     {
270         end2 = p + len;
271 
272         /* MaskGenAlgorithm ::= AlgorithmIdentifier (params = HashAlgorithm) */
273         if( ( ret = mbedtls_x509_get_alg( &p, end2, &alg_id, &alg_params ) ) != 0 )
274             return( ret );
275 
276         /* Only MFG1 is recognised for now */
277         if( MBEDTLS_OID_CMP( MBEDTLS_OID_MGF1, &alg_id ) != 0 )
278             return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE +
279                     MBEDTLS_ERR_OID_NOT_FOUND );
280 
281         /* Parse HashAlgorithm */
282         if( ( ret = x509_get_hash_alg( &alg_params, mgf_md ) ) != 0 )
283             return( ret );
284 
285         if( p != end2 )
286             return( MBEDTLS_ERR_X509_INVALID_ALG +
287                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
288     }
289     else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
290         return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
291 
292     if( p == end )
293         return( 0 );
294 
295     /*
296      * salt_len
297      */
298     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
299                     MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 2 ) ) == 0 )
300     {
301         end2 = p + len;
302 
303         if( ( ret = mbedtls_asn1_get_int( &p, end2, salt_len ) ) != 0 )
304             return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
305 
306         if( p != end2 )
307             return( MBEDTLS_ERR_X509_INVALID_ALG +
308                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
309     }
310     else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
311         return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
312 
313     if( p == end )
314         return( 0 );
315 
316     /*
317      * trailer_field (if present, must be 1)
318      */
319     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
320                     MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 3 ) ) == 0 )
321     {
322         int trailer_field;
323 
324         end2 = p + len;
325 
326         if( ( ret = mbedtls_asn1_get_int( &p, end2, &trailer_field ) ) != 0 )
327             return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
328 
329         if( p != end2 )
330             return( MBEDTLS_ERR_X509_INVALID_ALG +
331                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
332 
333         if( trailer_field != 1 )
334             return( MBEDTLS_ERR_X509_INVALID_ALG );
335     }
336     else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
337         return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
338 
339     if( p != end )
340         return( MBEDTLS_ERR_X509_INVALID_ALG +
341                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
342 
343     return( 0 );
344 }
345 #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
346 
347 /*
348  *  AttributeTypeAndValue ::= SEQUENCE {
349  *    type     AttributeType,
350  *    value    AttributeValue }
351  *
352  *  AttributeType ::= OBJECT IDENTIFIER
353  *
354  *  AttributeValue ::= ANY DEFINED BY AttributeType
355  */
356 static int x509_get_attr_type_value( unsigned char **p,
357                                      const unsigned char *end,
358                                      mbedtls_x509_name *cur )
359 {
360     int ret;
361     size_t len;
362     mbedtls_x509_buf *oid;
363     mbedtls_x509_buf *val;
364 
365     if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
366             MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
367         return( MBEDTLS_ERR_X509_INVALID_NAME + ret );
368 
369     if( ( end - *p ) < 1 )
370         return( MBEDTLS_ERR_X509_INVALID_NAME +
371                 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
372 
373     oid = &cur->oid;
374     oid->tag = **p;
375 
376     if( ( ret = mbedtls_asn1_get_tag( p, end, &oid->len, MBEDTLS_ASN1_OID ) ) != 0 )
377         return( MBEDTLS_ERR_X509_INVALID_NAME + ret );
378 
379     oid->p = *p;
380     *p += oid->len;
381 
382     if( ( end - *p ) < 1 )
383         return( MBEDTLS_ERR_X509_INVALID_NAME +
384                 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
385 
386     if( **p != MBEDTLS_ASN1_BMP_STRING && **p != MBEDTLS_ASN1_UTF8_STRING      &&
387         **p != MBEDTLS_ASN1_T61_STRING && **p != MBEDTLS_ASN1_PRINTABLE_STRING &&
388         **p != MBEDTLS_ASN1_IA5_STRING && **p != MBEDTLS_ASN1_UNIVERSAL_STRING &&
389         **p != MBEDTLS_ASN1_BIT_STRING )
390         return( MBEDTLS_ERR_X509_INVALID_NAME +
391                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
392 
393     val = &cur->val;
394     val->tag = *(*p)++;
395 
396     if( ( ret = mbedtls_asn1_get_len( p, end, &val->len ) ) != 0 )
397         return( MBEDTLS_ERR_X509_INVALID_NAME + ret );
398 
399     val->p = *p;
400     *p += val->len;
401 
402     cur->next = NULL;
403 
404     return( 0 );
405 }
406 
407 /*
408  *  Name ::= CHOICE { -- only one possibility for now --
409  *       rdnSequence  RDNSequence }
410  *
411  *  RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
412  *
413  *  RelativeDistinguishedName ::=
414  *    SET OF AttributeTypeAndValue
415  *
416  *  AttributeTypeAndValue ::= SEQUENCE {
417  *    type     AttributeType,
418  *    value    AttributeValue }
419  *
420  *  AttributeType ::= OBJECT IDENTIFIER
421  *
422  *  AttributeValue ::= ANY DEFINED BY AttributeType
423  *
424  * The data structure is optimized for the common case where each RDN has only
425  * one element, which is represented as a list of AttributeTypeAndValue.
426  * For the general case we still use a flat list, but we mark elements of the
427  * same set so that they are "merged" together in the functions that consume
428  * this list, eg mbedtls_x509_dn_gets().
429  */
430 int mbedtls_x509_get_name( unsigned char **p, const unsigned char *end,
431                    mbedtls_x509_name *cur )
432 {
433     int ret;
434     size_t set_len;
435     const unsigned char *end_set;
436 
437     /* don't use recursion, we'd risk stack overflow if not optimized */
438     while( 1 )
439     {
440         /*
441          * parse SET
442          */
443         if( ( ret = mbedtls_asn1_get_tag( p, end, &set_len,
444                 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SET ) ) != 0 )
445             return( MBEDTLS_ERR_X509_INVALID_NAME + ret );
446 
447         end_set  = *p + set_len;
448 
449         while( 1 )
450         {
451             if( ( ret = x509_get_attr_type_value( p, end_set, cur ) ) != 0 )
452                 return( ret );
453 
454             if( *p == end_set )
455                 break;
456 
457             /* Mark this item as being no the only one in a set */
458             cur->next_merged = 1;
459 
460             cur->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_name ) );
461 
462             if( cur->next == NULL )
463                 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
464 
465             cur = cur->next;
466         }
467 
468         /*
469          * continue until end of SEQUENCE is reached
470          */
471         if( *p == end )
472             return( 0 );
473 
474         cur->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_name ) );
475 
476         if( cur->next == NULL )
477             return( MBEDTLS_ERR_X509_ALLOC_FAILED );
478 
479         cur = cur->next;
480     }
481 }
482 
483 static int x509_parse_int( unsigned char **p, size_t n, int *res )
484 {
485     *res = 0;
486 
487     for( ; n > 0; --n )
488     {
489         if( ( **p < '0') || ( **p > '9' ) )
490             return ( MBEDTLS_ERR_X509_INVALID_DATE );
491 
492         *res *= 10;
493         *res += ( *(*p)++ - '0' );
494     }
495 
496     return( 0 );
497 }
498 
499 static int x509_date_is_valid(const mbedtls_x509_time *t)
500 {
501     int ret = MBEDTLS_ERR_X509_INVALID_DATE;
502 
503     CHECK_RANGE( 0, 9999, t->year );
504     CHECK_RANGE( 0, 23,   t->hour );
505     CHECK_RANGE( 0, 59,   t->min  );
506     CHECK_RANGE( 0, 59,   t->sec  );
507 
508     switch( t->mon )
509     {
510         case 1: case 3: case 5: case 7: case 8: case 10: case 12:
511             CHECK_RANGE( 1, 31, t->day );
512             break;
513         case 4: case 6: case 9: case 11:
514             CHECK_RANGE( 1, 30, t->day );
515             break;
516         case 2:
517             CHECK_RANGE( 1, 28 + (t->year % 4 == 0), t->day );
518             break;
519         default:
520             return( ret );
521     }
522 
523     return( 0 );
524 }
525 
526 /*
527  * Parse an ASN1_UTC_TIME (yearlen=2) or ASN1_GENERALIZED_TIME (yearlen=4)
528  * field.
529  */
530 static int x509_parse_time( unsigned char **p, size_t len, size_t yearlen,
531                             mbedtls_x509_time *tm )
532 {
533     int ret;
534 
535     /*
536      * Minimum length is 10 or 12 depending on yearlen
537      */
538     if ( len < yearlen + 8 )
539         return ( MBEDTLS_ERR_X509_INVALID_DATE );
540     len -= yearlen + 8;
541 
542     /*
543      * Parse year, month, day, hour, minute
544      */
545     CHECK( x509_parse_int( p, yearlen, &tm->year ) );
546     if ( 2 == yearlen )
547     {
548         if ( tm->year < 50 )
549             tm->year += 100;
550 
551         tm->year += 1900;
552     }
553 
554     CHECK( x509_parse_int( p, 2, &tm->mon ) );
555     CHECK( x509_parse_int( p, 2, &tm->day ) );
556     CHECK( x509_parse_int( p, 2, &tm->hour ) );
557     CHECK( x509_parse_int( p, 2, &tm->min ) );
558 
559     /*
560      * Parse seconds if present
561      */
562     if ( len >= 2 )
563     {
564         CHECK( x509_parse_int( p, 2, &tm->sec ) );
565         len -= 2;
566     }
567     else
568         return ( MBEDTLS_ERR_X509_INVALID_DATE );
569 
570     /*
571      * Parse trailing 'Z' if present
572      */
573     if ( 1 == len && 'Z' == **p )
574     {
575         (*p)++;
576         len--;
577     }
578 
579     /*
580      * We should have parsed all characters at this point
581      */
582     if ( 0 != len )
583         return ( MBEDTLS_ERR_X509_INVALID_DATE );
584 
585     CHECK( x509_date_is_valid( tm ) );
586 
587     return ( 0 );
588 }
589 
590 /*
591  *  Time ::= CHOICE {
592  *       utcTime        UTCTime,
593  *       generalTime    GeneralizedTime }
594  */
595 int mbedtls_x509_get_time( unsigned char **p, const unsigned char *end,
596                            mbedtls_x509_time *tm )
597 {
598     int ret;
599     size_t len, year_len;
600     unsigned char tag;
601 
602     if( ( end - *p ) < 1 )
603         return( MBEDTLS_ERR_X509_INVALID_DATE +
604                 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
605 
606     tag = **p;
607 
608     if( tag == MBEDTLS_ASN1_UTC_TIME )
609         year_len = 2;
610     else if( tag == MBEDTLS_ASN1_GENERALIZED_TIME )
611         year_len = 4;
612     else
613         return( MBEDTLS_ERR_X509_INVALID_DATE +
614                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
615 
616     (*p)++;
617     ret = mbedtls_asn1_get_len( p, end, &len );
618 
619     if( ret != 0 )
620         return( MBEDTLS_ERR_X509_INVALID_DATE + ret );
621 
622     return x509_parse_time( p, len, year_len, tm );
623 }
624 
625 int mbedtls_x509_get_sig( unsigned char **p, const unsigned char *end, mbedtls_x509_buf *sig )
626 {
627     int ret;
628     size_t len;
629     int tag_type;
630 
631     if( ( end - *p ) < 1 )
632         return( MBEDTLS_ERR_X509_INVALID_SIGNATURE +
633                 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
634 
635     tag_type = **p;
636 
637     if( ( ret = mbedtls_asn1_get_bitstring_null( p, end, &len ) ) != 0 )
638         return( MBEDTLS_ERR_X509_INVALID_SIGNATURE + ret );
639 
640     sig->tag = tag_type;
641     sig->len = len;
642     sig->p = *p;
643 
644     *p += len;
645 
646     return( 0 );
647 }
648 
649 /*
650  * Get signature algorithm from alg OID and optional parameters
651  */
652 int mbedtls_x509_get_sig_alg( const mbedtls_x509_buf *sig_oid, const mbedtls_x509_buf *sig_params,
653                       mbedtls_md_type_t *md_alg, mbedtls_pk_type_t *pk_alg,
654                       void **sig_opts )
655 {
656     int ret;
657 
658     if( *sig_opts != NULL )
659         return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
660 
661     if( ( ret = mbedtls_oid_get_sig_alg( sig_oid, md_alg, pk_alg ) ) != 0 )
662         return( MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG + ret );
663 
664 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
665     if( *pk_alg == MBEDTLS_PK_RSASSA_PSS )
666     {
667         mbedtls_pk_rsassa_pss_options *pss_opts;
668 
669         pss_opts = mbedtls_calloc( 1, sizeof( mbedtls_pk_rsassa_pss_options ) );
670         if( pss_opts == NULL )
671             return( MBEDTLS_ERR_X509_ALLOC_FAILED );
672 
673         ret = mbedtls_x509_get_rsassa_pss_params( sig_params,
674                                           md_alg,
675                                           &pss_opts->mgf1_hash_id,
676                                           &pss_opts->expected_salt_len );
677         if( ret != 0 )
678         {
679             mbedtls_free( pss_opts );
680             return( ret );
681         }
682 
683         *sig_opts = (void *) pss_opts;
684     }
685     else
686 #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
687     {
688         /* Make sure parameters are absent or NULL */
689         if( ( sig_params->tag != MBEDTLS_ASN1_NULL && sig_params->tag != 0 ) ||
690               sig_params->len != 0 )
691         return( MBEDTLS_ERR_X509_INVALID_ALG );
692     }
693 
694     return( 0 );
695 }
696 
697 /*
698  * X.509 Extensions (No parsing of extensions, pointer should
699  * be either manually updated or extensions should be parsed!)
700  */
701 int mbedtls_x509_get_ext( unsigned char **p, const unsigned char *end,
702                   mbedtls_x509_buf *ext, int tag )
703 {
704     int ret;
705     size_t len;
706 
707     if( *p == end )
708         return( 0 );
709 
710     ext->tag = **p;
711 
712     if( ( ret = mbedtls_asn1_get_tag( p, end, &ext->len,
713             MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | tag ) ) != 0 )
714         return( ret );
715 
716     ext->p = *p;
717     end = *p + ext->len;
718 
719     /*
720      * Extensions  ::=  SEQUENCE SIZE (1..MAX) OF Extension
721      *
722      * Extension  ::=  SEQUENCE  {
723      *      extnID      OBJECT IDENTIFIER,
724      *      critical    BOOLEAN DEFAULT FALSE,
725      *      extnValue   OCTET STRING  }
726      */
727     if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
728             MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
729         return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
730 
731     if( end != *p + len )
732         return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
733                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
734 
735     return( 0 );
736 }
737 
738 /*
739  * Store the name in printable form into buf; no more
740  * than size characters will be written
741  */
742 int mbedtls_x509_dn_gets( char *buf, size_t size, const mbedtls_x509_name *dn )
743 {
744     int ret;
745     size_t i, n;
746     unsigned char c, merge = 0;
747     const mbedtls_x509_name *name;
748     const char *short_name = NULL;
749     char s[MBEDTLS_X509_MAX_DN_NAME_SIZE], *p;
750 
751     memset( s, 0, sizeof( s ) );
752 
753     name = dn;
754     p = buf;
755     n = size;
756 
757     while( name != NULL )
758     {
759         if( !name->oid.p )
760         {
761             name = name->next;
762             continue;
763         }
764 
765         if( name != dn )
766         {
767             ret = mbedtls_snprintf( p, n, merge ? " + " : ", " );
768             MBEDTLS_X509_SAFE_SNPRINTF;
769         }
770 
771         ret = mbedtls_oid_get_attr_short_name( &name->oid, &short_name );
772 
773         if( ret == 0 )
774             ret = mbedtls_snprintf( p, n, "%s=", short_name );
775         else
776             ret = mbedtls_snprintf( p, n, "\?\?=" );
777         MBEDTLS_X509_SAFE_SNPRINTF;
778 
779         for( i = 0; i < name->val.len; i++ )
780         {
781             if( i >= sizeof( s ) - 1 )
782                 break;
783 
784             c = name->val.p[i];
785             if( c < 32 || c == 127 || ( c > 128 && c < 160 ) )
786                  s[i] = '?';
787             else s[i] = c;
788         }
789         s[i] = '\0';
790         ret = mbedtls_snprintf( p, n, "%s", s );
791         MBEDTLS_X509_SAFE_SNPRINTF;
792 
793         merge = name->next_merged;
794         name = name->next;
795     }
796 
797     return( (int) ( size - n ) );
798 }
799 
800 /*
801  * Store the serial in printable form into buf; no more
802  * than size characters will be written
803  */
804 int mbedtls_x509_serial_gets( char *buf, size_t size, const mbedtls_x509_buf *serial )
805 {
806     int ret;
807     size_t i, n, nr;
808     char *p;
809 
810     p = buf;
811     n = size;
812 
813     nr = ( serial->len <= 32 )
814         ? serial->len  : 28;
815 
816     for( i = 0; i < nr; i++ )
817     {
818         if( i == 0 && nr > 1 && serial->p[i] == 0x0 )
819             continue;
820 
821         ret = mbedtls_snprintf( p, n, "%02X%s",
822                 serial->p[i], ( i < nr - 1 ) ? ":" : "" );
823         MBEDTLS_X509_SAFE_SNPRINTF;
824     }
825 
826     if( nr != serial->len )
827     {
828         ret = mbedtls_snprintf( p, n, "...." );
829         MBEDTLS_X509_SAFE_SNPRINTF;
830     }
831 
832     return( (int) ( size - n ) );
833 }
834 
835 /*
836  * Helper for writing signature algorithms
837  */
838 int mbedtls_x509_sig_alg_gets( char *buf, size_t size, const mbedtls_x509_buf *sig_oid,
839                        mbedtls_pk_type_t pk_alg, mbedtls_md_type_t md_alg,
840                        const void *sig_opts )
841 {
842     int ret;
843     char *p = buf;
844     size_t n = size;
845     const char *desc = NULL;
846 
847     ret = mbedtls_oid_get_sig_alg_desc( sig_oid, &desc );
848     if( ret != 0 )
849         ret = mbedtls_snprintf( p, n, "???"  );
850     else
851         ret = mbedtls_snprintf( p, n, "%s", desc );
852     MBEDTLS_X509_SAFE_SNPRINTF;
853 
854 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
855     if( pk_alg == MBEDTLS_PK_RSASSA_PSS )
856     {
857         const mbedtls_pk_rsassa_pss_options *pss_opts;
858         const mbedtls_md_info_t *md_info, *mgf_md_info;
859 
860         pss_opts = (const mbedtls_pk_rsassa_pss_options *) sig_opts;
861 
862         md_info = mbedtls_md_info_from_type( md_alg );
863         mgf_md_info = mbedtls_md_info_from_type( pss_opts->mgf1_hash_id );
864 
865         ret = mbedtls_snprintf( p, n, " (%s, MGF1-%s, 0x%02X)",
866                               md_info ? mbedtls_md_get_name( md_info ) : "???",
867                               mgf_md_info ? mbedtls_md_get_name( mgf_md_info ) : "???",
868                               pss_opts->expected_salt_len );
869         MBEDTLS_X509_SAFE_SNPRINTF;
870     }
871 #else
872     ((void) pk_alg);
873     ((void) md_alg);
874     ((void) sig_opts);
875 #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
876 
877     return( (int)( size - n ) );
878 }
879 
880 /*
881  * Helper for writing "RSA key size", "EC key size", etc
882  */
883 int mbedtls_x509_key_size_helper( char *buf, size_t buf_size, const char *name )
884 {
885     char *p = buf;
886     size_t n = buf_size;
887     int ret;
888 
889     ret = mbedtls_snprintf( p, n, "%s key size", name );
890     MBEDTLS_X509_SAFE_SNPRINTF;
891 
892     return( 0 );
893 }
894 
895 #if defined(MBEDTLS_HAVE_TIME_DATE)
896 /*
897  * Set the time structure to the current time.
898  * Return 0 on success, non-zero on failure.
899  */
900 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
901 static int x509_get_current_time( mbedtls_x509_time *now )
902 {
903     SYSTEMTIME st;
904 
905     GetSystemTime( &st );
906 
907     now->year = st.wYear;
908     now->mon  = st.wMonth;
909     now->day  = st.wDay;
910     now->hour = st.wHour;
911     now->min  = st.wMinute;
912     now->sec  = st.wSecond;
913 
914     return( 0 );
915 }
916 #else
917 static int x509_get_current_time( mbedtls_x509_time *now )
918 {
919     struct tm *lt;
920     mbedtls_time_t tt;
921     int ret = 0;
922 
923 #if defined(MBEDTLS_THREADING_C)
924     if( mbedtls_mutex_lock( &mbedtls_threading_gmtime_mutex ) != 0 )
925         return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
926 #endif
927 
928     tt = mbedtls_time( NULL );
929     lt = gmtime( &tt );
930 
931     if( lt == NULL )
932         ret = -1;
933     else
934     {
935         now->year = lt->tm_year + 1900;
936         now->mon  = lt->tm_mon  + 1;
937         now->day  = lt->tm_mday;
938         now->hour = lt->tm_hour;
939         now->min  = lt->tm_min;
940         now->sec  = lt->tm_sec;
941     }
942 
943 #if defined(MBEDTLS_THREADING_C)
944     if( mbedtls_mutex_unlock( &mbedtls_threading_gmtime_mutex ) != 0 )
945         return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
946 #endif
947 
948     return( ret );
949 }
950 #endif /* _WIN32 && !EFIX64 && !EFI32 */
951 
952 /*
953  * Return 0 if before <= after, 1 otherwise
954  */
955 static int x509_check_time( const mbedtls_x509_time *before, const mbedtls_x509_time *after )
956 {
957     if( before->year  > after->year )
958         return( 1 );
959 
960     if( before->year == after->year &&
961         before->mon   > after->mon )
962         return( 1 );
963 
964     if( before->year == after->year &&
965         before->mon  == after->mon  &&
966         before->day   > after->day )
967         return( 1 );
968 
969     if( before->year == after->year &&
970         before->mon  == after->mon  &&
971         before->day  == after->day  &&
972         before->hour  > after->hour )
973         return( 1 );
974 
975     if( before->year == after->year &&
976         before->mon  == after->mon  &&
977         before->day  == after->day  &&
978         before->hour == after->hour &&
979         before->min   > after->min  )
980         return( 1 );
981 
982     if( before->year == after->year &&
983         before->mon  == after->mon  &&
984         before->day  == after->day  &&
985         before->hour == after->hour &&
986         before->min  == after->min  &&
987         before->sec   > after->sec  )
988         return( 1 );
989 
990     return( 0 );
991 }
992 
993 int mbedtls_x509_time_is_past( const mbedtls_x509_time *to )
994 {
995     mbedtls_x509_time now;
996 
997     if( x509_get_current_time( &now ) != 0 )
998         return( 1 );
999 
1000     return( x509_check_time( &now, to ) );
1001 }
1002 
1003 int mbedtls_x509_time_is_future( const mbedtls_x509_time *from )
1004 {
1005     mbedtls_x509_time now;
1006 
1007     if( x509_get_current_time( &now ) != 0 )
1008         return( 1 );
1009 
1010     return( x509_check_time( from, &now ) );
1011 }
1012 
1013 #else  /* MBEDTLS_HAVE_TIME_DATE */
1014 
1015 int mbedtls_x509_time_is_past( const mbedtls_x509_time *to )
1016 {
1017     ((void) to);
1018     return( 0 );
1019 }
1020 
1021 int mbedtls_x509_time_is_future( const mbedtls_x509_time *from )
1022 {
1023     ((void) from);
1024     return( 0 );
1025 }
1026 #endif /* MBEDTLS_HAVE_TIME_DATE */
1027 
1028 #if defined(MBEDTLS_SELF_TEST)
1029 
1030 #include "mbedtls/x509_crt.h"
1031 #include "mbedtls/certs.h"
1032 
1033 /*
1034  * Checkup routine
1035  */
1036 int mbedtls_x509_self_test( int verbose )
1037 {
1038 #if defined(MBEDTLS_CERTS_C) && defined(MBEDTLS_SHA256_C)
1039     int ret;
1040     uint32_t flags;
1041     mbedtls_x509_crt cacert;
1042     mbedtls_x509_crt clicert;
1043 
1044     if( verbose != 0 )
1045         mbedtls_printf( "  X.509 certificate load: " );
1046 
1047     mbedtls_x509_crt_init( &clicert );
1048 
1049     ret = mbedtls_x509_crt_parse( &clicert, (const unsigned char *) mbedtls_test_cli_crt,
1050                            mbedtls_test_cli_crt_len );
1051     if( ret != 0 )
1052     {
1053         if( verbose != 0 )
1054             mbedtls_printf( "failed\n" );
1055 
1056         return( ret );
1057     }
1058 
1059     mbedtls_x509_crt_init( &cacert );
1060 
1061     ret = mbedtls_x509_crt_parse( &cacert, (const unsigned char *) mbedtls_test_ca_crt,
1062                           mbedtls_test_ca_crt_len );
1063     if( ret != 0 )
1064     {
1065         if( verbose != 0 )
1066             mbedtls_printf( "failed\n" );
1067 
1068         return( ret );
1069     }
1070 
1071     if( verbose != 0 )
1072         mbedtls_printf( "passed\n  X.509 signature verify: ");
1073 
1074     ret = mbedtls_x509_crt_verify( &clicert, &cacert, NULL, NULL, &flags, NULL, NULL );
1075     if( ret != 0 )
1076     {
1077         if( verbose != 0 )
1078             mbedtls_printf( "failed\n" );
1079 
1080         return( ret );
1081     }
1082 
1083     if( verbose != 0 )
1084         mbedtls_printf( "passed\n\n");
1085 
1086     mbedtls_x509_crt_free( &cacert  );
1087     mbedtls_x509_crt_free( &clicert );
1088 
1089     return( 0 );
1090 #else
1091     ((void) verbose);
1092     return( 0 );
1093 #endif /* MBEDTLS_CERTS_C && MBEDTLS_SHA1_C */
1094 }
1095 
1096 #endif /* MBEDTLS_SELF_TEST */
1097 
1098 #endif /* MBEDTLS_X509_USE_C */
1099