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1 /*
2  *  X.509 common functions for parsing and verification
3  *
4  *  Copyright The Mbed TLS Contributors
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 /*
20  *  The ITU-T X.509 standard defines a certificate format for PKI.
21  *
22  *  http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
23  *  http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
24  *  http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
25  *
26  *  http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
27  *  http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
28  */
29 
30 #include "common.h"
31 
32 #if defined(MBEDTLS_X509_USE_C)
33 
34 #include "mbedtls/x509.h"
35 #include "mbedtls/asn1.h"
36 #include "mbedtls/error.h"
37 #include "mbedtls/oid.h"
38 
39 #include <stdio.h>
40 #include <string.h>
41 
42 #if defined(MBEDTLS_PEM_PARSE_C)
43 #include "mbedtls/pem.h"
44 #endif
45 
46 #if defined(MBEDTLS_PLATFORM_C)
47 #include "mbedtls/platform.h"
48 #else
49 #include <stdio.h>
50 #include <stdlib.h>
51 #define mbedtls_free      free
52 #define mbedtls_calloc    calloc
53 #define mbedtls_printf    printf
54 #define mbedtls_snprintf  snprintf
55 #endif
56 
57 #if defined(MBEDTLS_HAVE_TIME)
58 #include "mbedtls/platform_time.h"
59 #endif
60 #if defined(MBEDTLS_HAVE_TIME_DATE)
61 #include "mbedtls/platform_util.h"
62 #include <time.h>
63 #endif
64 
65 #if defined(VENDOR_CUSTOMISE_CHECK_CERT_DATE_C)
66 #include "mbedtls/hw_polarssl_api.h"
67 #endif
68 
69 #define CHECK(code) if( ( ret = ( code ) ) != 0 ){ return( ret ); }
70 #define CHECK_RANGE(min, max, val)                      \
71     do                                                  \
72     {                                                   \
73         if( ( val ) < ( min ) || ( val ) > ( max ) )    \
74         {                                               \
75             return( ret );                              \
76         }                                               \
77     } while( 0 )
78 
79 /*
80  *  CertificateSerialNumber  ::=  INTEGER
81  */
mbedtls_x509_get_serial(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * serial)82 int mbedtls_x509_get_serial( unsigned char **p, const unsigned char *end,
83                      mbedtls_x509_buf *serial )
84 {
85     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
86 
87     if( ( end - *p ) < 1 )
88         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_SERIAL,
89                 MBEDTLS_ERR_ASN1_OUT_OF_DATA ) );
90 
91     if( **p != ( MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_PRIMITIVE | 2 ) &&
92         **p !=   MBEDTLS_ASN1_INTEGER )
93         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_SERIAL,
94                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
95 
96     serial->tag = *(*p)++;
97 
98     if( ( ret = mbedtls_asn1_get_len( p, end, &serial->len ) ) != 0 )
99         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_SERIAL, ret ) );
100 
101     serial->p = *p;
102     *p += serial->len;
103 
104     return( 0 );
105 }
106 
107 /* Get an algorithm identifier without parameters (eg for signatures)
108  *
109  *  AlgorithmIdentifier  ::=  SEQUENCE  {
110  *       algorithm               OBJECT IDENTIFIER,
111  *       parameters              ANY DEFINED BY algorithm OPTIONAL  }
112  */
mbedtls_x509_get_alg_null(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * alg)113 int mbedtls_x509_get_alg_null( unsigned char **p, const unsigned char *end,
114                        mbedtls_x509_buf *alg )
115 {
116     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
117 
118     if( ( ret = mbedtls_asn1_get_alg_null( p, end, alg ) ) != 0 )
119         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
120 
121     return( 0 );
122 }
123 
124 /*
125  * Parse an algorithm identifier with (optional) parameters
126  */
mbedtls_x509_get_alg(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * alg,mbedtls_x509_buf * params)127 int mbedtls_x509_get_alg( unsigned char **p, const unsigned char *end,
128                   mbedtls_x509_buf *alg, mbedtls_x509_buf *params )
129 {
130     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
131 
132     if( ( ret = mbedtls_asn1_get_alg( p, end, alg, params ) ) != 0 )
133         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
134 
135     return( 0 );
136 }
137 
138 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
139 /*
140  * HashAlgorithm ::= AlgorithmIdentifier
141  *
142  * AlgorithmIdentifier  ::=  SEQUENCE  {
143  *      algorithm               OBJECT IDENTIFIER,
144  *      parameters              ANY DEFINED BY algorithm OPTIONAL  }
145  *
146  * For HashAlgorithm, parameters MUST be NULL or absent.
147  */
x509_get_hash_alg(const mbedtls_x509_buf * alg,mbedtls_md_type_t * md_alg)148 static int x509_get_hash_alg( const mbedtls_x509_buf *alg, mbedtls_md_type_t *md_alg )
149 {
150     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
151     unsigned char *p;
152     const unsigned char *end;
153     mbedtls_x509_buf md_oid;
154     size_t len;
155 
156     /* Make sure we got a SEQUENCE and setup bounds */
157     if( alg->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
158         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG,
159                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
160 
161     p = alg->p;
162     end = p + alg->len;
163 
164     if( p >= end )
165         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG,
166                 MBEDTLS_ERR_ASN1_OUT_OF_DATA ) );
167 
168     /* Parse md_oid */
169     md_oid.tag = *p;
170 
171     if( ( ret = mbedtls_asn1_get_tag( &p, end, &md_oid.len, MBEDTLS_ASN1_OID ) ) != 0 )
172         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
173 
174     md_oid.p = p;
175     p += md_oid.len;
176 
177     /* Get md_alg from md_oid */
178     if( ( ret = mbedtls_oid_get_md_alg( &md_oid, md_alg ) ) != 0 )
179         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
180 
181     /* Make sure params is absent of NULL */
182     if( p == end )
183         return( 0 );
184 
185     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_NULL ) ) != 0 || len != 0 )
186         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
187 
188     if( p != end )
189         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG,
190                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
191 
192     return( 0 );
193 }
194 
195 /*
196  *    RSASSA-PSS-params  ::=  SEQUENCE  {
197  *       hashAlgorithm     [0] HashAlgorithm DEFAULT sha1Identifier,
198  *       maskGenAlgorithm  [1] MaskGenAlgorithm DEFAULT mgf1SHA1Identifier,
199  *       saltLength        [2] INTEGER DEFAULT 20,
200  *       trailerField      [3] INTEGER DEFAULT 1  }
201  *    -- Note that the tags in this Sequence are explicit.
202  *
203  * RFC 4055 (which defines use of RSASSA-PSS in PKIX) states that the value
204  * of trailerField MUST be 1, and PKCS#1 v2.2 doesn't even define any other
205  * option. Enfore this at parsing time.
206  */
mbedtls_x509_get_rsassa_pss_params(const mbedtls_x509_buf * params,mbedtls_md_type_t * md_alg,mbedtls_md_type_t * mgf_md,int * salt_len)207 int mbedtls_x509_get_rsassa_pss_params( const mbedtls_x509_buf *params,
208                                 mbedtls_md_type_t *md_alg, mbedtls_md_type_t *mgf_md,
209                                 int *salt_len )
210 {
211     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
212     unsigned char *p;
213     const unsigned char *end, *end2;
214     size_t len;
215     mbedtls_x509_buf alg_id, alg_params;
216 
217     /* First set everything to defaults */
218     *md_alg = MBEDTLS_MD_SHA1;
219     *mgf_md = MBEDTLS_MD_SHA1;
220     *salt_len = 20;
221 
222     /* Make sure params is a SEQUENCE and setup bounds */
223     if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
224         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG,
225                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
226 
227     p = (unsigned char *) params->p;
228     end = p + params->len;
229 
230     if( p == end )
231         return( 0 );
232 
233     /*
234      * HashAlgorithm
235      */
236     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
237                     MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) == 0 )
238     {
239         end2 = p + len;
240 
241         /* HashAlgorithm ::= AlgorithmIdentifier (without parameters) */
242         if( ( ret = mbedtls_x509_get_alg_null( &p, end2, &alg_id ) ) != 0 )
243             return( ret );
244 
245         if( ( ret = mbedtls_oid_get_md_alg( &alg_id, md_alg ) ) != 0 )
246             return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
247 
248         if( p != end2 )
249             return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG,
250                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
251     }
252     else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
253         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
254 
255     if( p == end )
256         return( 0 );
257 
258     /*
259      * MaskGenAlgorithm
260      */
261     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
262                     MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 1 ) ) == 0 )
263     {
264         end2 = p + len;
265 
266         /* MaskGenAlgorithm ::= AlgorithmIdentifier (params = HashAlgorithm) */
267         if( ( ret = mbedtls_x509_get_alg( &p, end2, &alg_id, &alg_params ) ) != 0 )
268             return( ret );
269 
270         /* Only MFG1 is recognised for now */
271         if( MBEDTLS_OID_CMP( MBEDTLS_OID_MGF1, &alg_id ) != 0 )
272             return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE,
273                     MBEDTLS_ERR_OID_NOT_FOUND ) );
274 
275         /* Parse HashAlgorithm */
276         if( ( ret = x509_get_hash_alg( &alg_params, mgf_md ) ) != 0 )
277             return( ret );
278 
279         if( p != end2 )
280             return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG,
281                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
282     }
283     else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
284         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
285 
286     if( p == end )
287         return( 0 );
288 
289     /*
290      * salt_len
291      */
292     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
293                     MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 2 ) ) == 0 )
294     {
295         end2 = p + len;
296 
297         if( ( ret = mbedtls_asn1_get_int( &p, end2, salt_len ) ) != 0 )
298             return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
299 
300         if( p != end2 )
301             return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG,
302                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
303     }
304     else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
305         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
306 
307     if( p == end )
308         return( 0 );
309 
310     /*
311      * trailer_field (if present, must be 1)
312      */
313     if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
314                     MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 3 ) ) == 0 )
315     {
316         int trailer_field;
317 
318         end2 = p + len;
319 
320         if( ( ret = mbedtls_asn1_get_int( &p, end2, &trailer_field ) ) != 0 )
321             return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
322 
323         if( p != end2 )
324             return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG,
325                     MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
326 
327         if( trailer_field != 1 )
328             return( MBEDTLS_ERR_X509_INVALID_ALG );
329     }
330     else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
331         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG, ret ) );
332 
333     if( p != end )
334         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_ALG,
335                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
336 
337     return( 0 );
338 }
339 #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
340 
341 /*
342  *  AttributeTypeAndValue ::= SEQUENCE {
343  *    type     AttributeType,
344  *    value    AttributeValue }
345  *
346  *  AttributeType ::= OBJECT IDENTIFIER
347  *
348  *  AttributeValue ::= ANY DEFINED BY AttributeType
349  */
x509_get_attr_type_value(unsigned char ** p,const unsigned char * end,mbedtls_x509_name * cur)350 static int x509_get_attr_type_value( unsigned char **p,
351                                      const unsigned char *end,
352                                      mbedtls_x509_name *cur )
353 {
354     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
355     size_t len;
356     mbedtls_x509_buf *oid;
357     mbedtls_x509_buf *val;
358 
359     if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
360             MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
361         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_NAME, ret ) );
362 
363     end = *p + len;
364 
365     if( ( end - *p ) < 1 )
366         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_NAME,
367                 MBEDTLS_ERR_ASN1_OUT_OF_DATA ) );
368 
369     oid = &cur->oid;
370     oid->tag = **p;
371 
372     if( ( ret = mbedtls_asn1_get_tag( p, end, &oid->len, MBEDTLS_ASN1_OID ) ) != 0 )
373         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_NAME, ret ) );
374 
375     oid->p = *p;
376     *p += oid->len;
377 
378     if( ( end - *p ) < 1 )
379         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_NAME,
380                 MBEDTLS_ERR_ASN1_OUT_OF_DATA ) );
381 
382     if( **p != MBEDTLS_ASN1_BMP_STRING && **p != MBEDTLS_ASN1_UTF8_STRING      &&
383         **p != MBEDTLS_ASN1_T61_STRING && **p != MBEDTLS_ASN1_PRINTABLE_STRING &&
384         **p != MBEDTLS_ASN1_IA5_STRING && **p != MBEDTLS_ASN1_UNIVERSAL_STRING &&
385         **p != MBEDTLS_ASN1_BIT_STRING )
386         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_NAME,
387                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
388 
389     val = &cur->val;
390     val->tag = *(*p)++;
391 
392     if( ( ret = mbedtls_asn1_get_len( p, end, &val->len ) ) != 0 )
393         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_NAME, ret ) );
394 
395     val->p = *p;
396     *p += val->len;
397 
398     if( *p != end )
399     {
400         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_NAME,
401                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
402     }
403 
404     cur->next = NULL;
405 
406     return( 0 );
407 }
408 
409 /*
410  *  Name ::= CHOICE { -- only one possibility for now --
411  *       rdnSequence  RDNSequence }
412  *
413  *  RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
414  *
415  *  RelativeDistinguishedName ::=
416  *    SET OF AttributeTypeAndValue
417  *
418  *  AttributeTypeAndValue ::= SEQUENCE {
419  *    type     AttributeType,
420  *    value    AttributeValue }
421  *
422  *  AttributeType ::= OBJECT IDENTIFIER
423  *
424  *  AttributeValue ::= ANY DEFINED BY AttributeType
425  *
426  * The data structure is optimized for the common case where each RDN has only
427  * one element, which is represented as a list of AttributeTypeAndValue.
428  * For the general case we still use a flat list, but we mark elements of the
429  * same set so that they are "merged" together in the functions that consume
430  * this list, eg mbedtls_x509_dn_gets().
431  */
mbedtls_x509_get_name(unsigned char ** p,const unsigned char * end,mbedtls_x509_name * cur)432 int mbedtls_x509_get_name( unsigned char **p, const unsigned char *end,
433                    mbedtls_x509_name *cur )
434 {
435     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
436     size_t set_len;
437     const unsigned char *end_set;
438 
439     /* don't use recursion, we'd risk stack overflow if not optimized */
440     while( 1 )
441     {
442         /*
443          * parse SET
444          */
445         if( ( ret = mbedtls_asn1_get_tag( p, end, &set_len,
446                 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SET ) ) != 0 )
447             return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_NAME, ret ) );
448 
449         end_set  = *p + set_len;
450 
451         while( 1 )
452         {
453             if( ( ret = x509_get_attr_type_value( p, end_set, cur ) ) != 0 )
454                 return( ret );
455 
456             if( *p == end_set )
457                 break;
458 
459             /* Mark this item as being no the only one in a set */
460             cur->next_merged = 1;
461 
462             cur->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_name ) );
463 
464             if( cur->next == NULL )
465                 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
466 
467             cur = cur->next;
468         }
469 
470         /*
471          * continue until end of SEQUENCE is reached
472          */
473         if( *p == end )
474             return( 0 );
475 
476         cur->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_name ) );
477 
478         if( cur->next == NULL )
479             return( MBEDTLS_ERR_X509_ALLOC_FAILED );
480 
481         cur = cur->next;
482     }
483 }
484 
x509_parse_int(unsigned char ** p,size_t n,int * res)485 static int x509_parse_int( unsigned char **p, size_t n, int *res )
486 {
487     *res = 0;
488 
489     for( ; n > 0; --n )
490     {
491         if( ( **p < '0') || ( **p > '9' ) )
492             return ( MBEDTLS_ERR_X509_INVALID_DATE );
493 
494         *res *= 10;
495         *res += ( *(*p)++ - '0' );
496     }
497 
498     return( 0 );
499 }
500 
x509_date_is_valid(const mbedtls_x509_time * t)501 static int x509_date_is_valid(const mbedtls_x509_time *t )
502 {
503     int ret = MBEDTLS_ERR_X509_INVALID_DATE;
504     int month_len;
505 
506     CHECK_RANGE( 0, 9999, t->year );
507     CHECK_RANGE( 0, 23,   t->hour );
508     CHECK_RANGE( 0, 59,   t->min  );
509     CHECK_RANGE( 0, 59,   t->sec  );
510 
511     switch( t->mon )
512     {
513         case 1: case 3: case 5: case 7: case 8: case 10: case 12:
514             month_len = 31;
515             break;
516         case 4: case 6: case 9: case 11:
517             month_len = 30;
518             break;
519         case 2:
520             if( ( !( t->year % 4 ) && t->year % 100 ) ||
521                 !( t->year % 400 ) )
522                 month_len = 29;
523             else
524                 month_len = 28;
525             break;
526         default:
527             return( ret );
528     }
529     CHECK_RANGE( 1, month_len, t->day );
530 
531     return( 0 );
532 }
533 
534 /*
535  * Parse an ASN1_UTC_TIME (yearlen=2) or ASN1_GENERALIZED_TIME (yearlen=4)
536  * field.
537  */
x509_parse_time(unsigned char ** p,size_t len,size_t yearlen,mbedtls_x509_time * tm)538 static int x509_parse_time( unsigned char **p, size_t len, size_t yearlen,
539                             mbedtls_x509_time *tm )
540 {
541     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
542 
543     /*
544      * Minimum length is 10 or 12 depending on yearlen
545      */
546     if ( len < yearlen + 8 )
547         return ( MBEDTLS_ERR_X509_INVALID_DATE );
548     len -= yearlen + 8;
549 
550     /*
551      * Parse year, month, day, hour, minute
552      */
553     CHECK( x509_parse_int( p, yearlen, &tm->year ) );
554     if ( 2 == yearlen )
555     {
556         if ( tm->year < 50 )
557             tm->year += 100;
558 
559         tm->year += 1900;
560     }
561 
562     CHECK( x509_parse_int( p, 2, &tm->mon ) );
563     CHECK( x509_parse_int( p, 2, &tm->day ) );
564     CHECK( x509_parse_int( p, 2, &tm->hour ) );
565     CHECK( x509_parse_int( p, 2, &tm->min ) );
566 
567     /*
568      * Parse seconds if present
569      */
570     if ( len >= 2 )
571     {
572         CHECK( x509_parse_int( p, 2, &tm->sec ) );
573         len -= 2;
574     }
575     else
576         return ( MBEDTLS_ERR_X509_INVALID_DATE );
577 
578     /*
579      * Parse trailing 'Z' if present
580      */
581     if ( 1 == len && 'Z' == **p )
582     {
583         (*p)++;
584         len--;
585     }
586 
587     /*
588      * We should have parsed all characters at this point
589      */
590     if ( 0 != len )
591         return ( MBEDTLS_ERR_X509_INVALID_DATE );
592 
593     CHECK( x509_date_is_valid( tm ) );
594 
595     return ( 0 );
596 }
597 
598 /*
599  *  Time ::= CHOICE {
600  *       utcTime        UTCTime,
601  *       generalTime    GeneralizedTime }
602  */
mbedtls_x509_get_time(unsigned char ** p,const unsigned char * end,mbedtls_x509_time * tm)603 int mbedtls_x509_get_time( unsigned char **p, const unsigned char *end,
604                            mbedtls_x509_time *tm )
605 {
606     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
607     size_t len, year_len;
608     unsigned char tag;
609 
610     if( ( end - *p ) < 1 )
611         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_DATE,
612                 MBEDTLS_ERR_ASN1_OUT_OF_DATA ) );
613 
614     tag = **p;
615 
616     if( tag == MBEDTLS_ASN1_UTC_TIME )
617         year_len = 2;
618     else if( tag == MBEDTLS_ASN1_GENERALIZED_TIME )
619         year_len = 4;
620     else
621         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_DATE,
622                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
623 
624     (*p)++;
625     ret = mbedtls_asn1_get_len( p, end, &len );
626 
627     if( ret != 0 )
628         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_DATE, ret ) );
629 
630     return x509_parse_time( p, len, year_len, tm );
631 }
632 
mbedtls_x509_get_sig(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * sig)633 int mbedtls_x509_get_sig( unsigned char **p, const unsigned char *end, mbedtls_x509_buf *sig )
634 {
635     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
636     size_t len;
637     int tag_type;
638 
639     if( ( end - *p ) < 1 )
640         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_SIGNATURE,
641                 MBEDTLS_ERR_ASN1_OUT_OF_DATA ) );
642 
643     tag_type = **p;
644 
645     if( ( ret = mbedtls_asn1_get_bitstring_null( p, end, &len ) ) != 0 )
646         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_SIGNATURE, ret ) );
647 
648     sig->tag = tag_type;
649     sig->len = len;
650     sig->p = *p;
651 
652     *p += len;
653 
654     return( 0 );
655 }
656 
657 /*
658  * Get signature algorithm from alg OID and optional parameters
659  */
mbedtls_x509_get_sig_alg(const mbedtls_x509_buf * sig_oid,const mbedtls_x509_buf * sig_params,mbedtls_md_type_t * md_alg,mbedtls_pk_type_t * pk_alg,void ** sig_opts)660 int mbedtls_x509_get_sig_alg( const mbedtls_x509_buf *sig_oid, const mbedtls_x509_buf *sig_params,
661                       mbedtls_md_type_t *md_alg, mbedtls_pk_type_t *pk_alg,
662                       void **sig_opts )
663 {
664     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
665 
666     if( *sig_opts != NULL )
667         return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
668 
669     if( ( ret = mbedtls_oid_get_sig_alg( sig_oid, md_alg, pk_alg ) ) != 0 )
670         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG, ret ) );
671 
672 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
673     if( *pk_alg == MBEDTLS_PK_RSASSA_PSS )
674     {
675         mbedtls_pk_rsassa_pss_options *pss_opts;
676 
677         pss_opts = mbedtls_calloc( 1, sizeof( mbedtls_pk_rsassa_pss_options ) );
678         if( pss_opts == NULL )
679             return( MBEDTLS_ERR_X509_ALLOC_FAILED );
680 
681         ret = mbedtls_x509_get_rsassa_pss_params( sig_params,
682                                           md_alg,
683                                           &pss_opts->mgf1_hash_id,
684                                           &pss_opts->expected_salt_len );
685         if( ret != 0 )
686         {
687             mbedtls_free( pss_opts );
688             return( ret );
689         }
690 
691         *sig_opts = (void *) pss_opts;
692     }
693     else
694 #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
695     {
696         /* Make sure parameters are absent or NULL */
697         if( ( sig_params->tag != MBEDTLS_ASN1_NULL && sig_params->tag != 0 ) ||
698               sig_params->len != 0 )
699         return( MBEDTLS_ERR_X509_INVALID_ALG );
700     }
701 
702     return( 0 );
703 }
704 
705 /*
706  * X.509 Extensions (No parsing of extensions, pointer should
707  * be either manually updated or extensions should be parsed!)
708  */
mbedtls_x509_get_ext(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * ext,int tag)709 int mbedtls_x509_get_ext( unsigned char **p, const unsigned char *end,
710                           mbedtls_x509_buf *ext, int tag )
711 {
712     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
713     size_t len;
714 
715     /* Extension structure use EXPLICIT tagging. That is, the actual
716      * `Extensions` structure is wrapped by a tag-length pair using
717      * the respective context-specific tag. */
718     ret = mbedtls_asn1_get_tag( p, end, &ext->len,
719               MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | tag );
720     if( ret != 0 )
721         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
722 
723     ext->tag = MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | tag;
724     ext->p   = *p;
725     end      = *p + ext->len;
726 
727     /*
728      * Extensions  ::=  SEQUENCE SIZE (1..MAX) OF Extension
729      */
730     if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
731             MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
732         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
733 
734     if( end != *p + len )
735         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
736                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
737 
738     return( 0 );
739 }
740 
741 /*
742  * Store the name in printable form into buf; no more
743  * than size characters will be written
744  */
mbedtls_x509_dn_gets(char * buf,size_t size,const mbedtls_x509_name * dn)745 int mbedtls_x509_dn_gets( char *buf, size_t size, const mbedtls_x509_name *dn )
746 {
747     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
748     size_t i, n;
749     unsigned char c, merge = 0;
750     const mbedtls_x509_name *name;
751     const char *short_name = NULL;
752     char s[MBEDTLS_X509_MAX_DN_NAME_SIZE], *p;
753 
754     memset( s, 0, sizeof( s ) );
755 
756     name = dn;
757     p = buf;
758     n = size;
759 
760     while( name != NULL )
761     {
762         if( !name->oid.p )
763         {
764             name = name->next;
765             continue;
766         }
767 
768         if( name != dn )
769         {
770             ret = mbedtls_snprintf( p, n, merge ? " + " : ", " );
771             MBEDTLS_X509_SAFE_SNPRINTF;
772         }
773 
774         ret = mbedtls_oid_get_attr_short_name( &name->oid, &short_name );
775 
776         if( ret == 0 )
777             ret = mbedtls_snprintf( p, n, "%s=", short_name );
778         else
779             ret = mbedtls_snprintf( p, n, "\?\?=" );
780         MBEDTLS_X509_SAFE_SNPRINTF;
781 
782         for( i = 0; i < name->val.len; i++ )
783         {
784             if( i >= sizeof( s ) - 1 )
785                 break;
786 
787             c = name->val.p[i];
788             if( c < 32 || c >= 127 )
789                  s[i] = '?';
790             else s[i] = c;
791         }
792         s[i] = '\0';
793         ret = mbedtls_snprintf( p, n, "%s", s );
794         MBEDTLS_X509_SAFE_SNPRINTF;
795 
796         merge = name->next_merged;
797         name = name->next;
798     }
799 
800     return( (int) ( size - n ) );
801 }
802 
803 /*
804  * Store the serial in printable form into buf; no more
805  * than size characters will be written
806  */
mbedtls_x509_serial_gets(char * buf,size_t size,const mbedtls_x509_buf * serial)807 int mbedtls_x509_serial_gets( char *buf, size_t size, const mbedtls_x509_buf *serial )
808 {
809     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
810     size_t i, n, nr;
811     char *p;
812 
813     p = buf;
814     n = size;
815 
816     nr = ( serial->len <= 32 )
817         ? serial->len  : 28;
818 
819     for( i = 0; i < nr; i++ )
820     {
821         if( i == 0 && nr > 1 && serial->p[i] == 0x0 )
822             continue;
823 
824         ret = mbedtls_snprintf( p, n, "%02X%s",
825                 serial->p[i], ( i < nr - 1 ) ? ":" : "" );
826         MBEDTLS_X509_SAFE_SNPRINTF;
827     }
828 
829     if( nr != serial->len )
830     {
831         ret = mbedtls_snprintf( p, n, "...." );
832         MBEDTLS_X509_SAFE_SNPRINTF;
833     }
834 
835     return( (int) ( size - n ) );
836 }
837 
838 #if !defined(MBEDTLS_X509_REMOVE_INFO)
839 /*
840  * Helper for writing signature algorithms
841  */
mbedtls_x509_sig_alg_gets(char * buf,size_t size,const mbedtls_x509_buf * sig_oid,mbedtls_pk_type_t pk_alg,mbedtls_md_type_t md_alg,const void * sig_opts)842 int mbedtls_x509_sig_alg_gets( char *buf, size_t size, const mbedtls_x509_buf *sig_oid,
843                        mbedtls_pk_type_t pk_alg, mbedtls_md_type_t md_alg,
844                        const void *sig_opts )
845 {
846     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
847     char *p = buf;
848     size_t n = size;
849     const char *desc = NULL;
850 
851     ret = mbedtls_oid_get_sig_alg_desc( sig_oid, &desc );
852     if( ret != 0 )
853         ret = mbedtls_snprintf( p, n, "???"  );
854     else
855         ret = mbedtls_snprintf( p, n, "%s", desc );
856     MBEDTLS_X509_SAFE_SNPRINTF;
857 
858 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
859     if( pk_alg == MBEDTLS_PK_RSASSA_PSS )
860     {
861         const mbedtls_pk_rsassa_pss_options *pss_opts;
862         const mbedtls_md_info_t *md_info, *mgf_md_info;
863 
864         pss_opts = (const mbedtls_pk_rsassa_pss_options *) sig_opts;
865 
866         md_info = mbedtls_md_info_from_type( md_alg );
867         mgf_md_info = mbedtls_md_info_from_type( pss_opts->mgf1_hash_id );
868 
869         ret = mbedtls_snprintf( p, n, " (%s, MGF1-%s, 0x%02X)",
870                               md_info ? mbedtls_md_get_name( md_info ) : "???",
871                               mgf_md_info ? mbedtls_md_get_name( mgf_md_info ) : "???",
872                               (unsigned int) pss_opts->expected_salt_len );
873         MBEDTLS_X509_SAFE_SNPRINTF;
874     }
875 #else
876     ((void) pk_alg);
877     ((void) md_alg);
878     ((void) sig_opts);
879 #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
880 
881     return( (int)( size - n ) );
882 }
883 #endif /* MBEDTLS_X509_REMOVE_INFO */
884 
885 /*
886  * Helper for writing "RSA key size", "EC key size", etc
887  */
mbedtls_x509_key_size_helper(char * buf,size_t buf_size,const char * name)888 int mbedtls_x509_key_size_helper( char *buf, size_t buf_size, const char *name )
889 {
890     char *p = buf;
891     size_t n = buf_size;
892     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
893 
894     ret = mbedtls_snprintf( p, n, "%s key size", name );
895     MBEDTLS_X509_SAFE_SNPRINTF;
896 
897     return( 0 );
898 }
899 
900 #if defined(MBEDTLS_HAVE_TIME_DATE)
901 /*
902  * Set the time structure to the current time.
903  * Return 0 on success, non-zero on failure.
904  */
x509_get_current_time(mbedtls_x509_time * now)905 static int x509_get_current_time( mbedtls_x509_time *now )
906 {
907     struct tm *lt, tm_buf;
908     mbedtls_time_t tt;
909     int ret = 0;
910 
911     tt = mbedtls_time( NULL );
912     lt = mbedtls_platform_gmtime_r( &tt, &tm_buf );
913 
914     if( lt == NULL )
915         ret = -1;
916     else
917     {
918         now->year = lt->tm_year + 1900;
919         now->mon  = lt->tm_mon  + 1;
920         now->day  = lt->tm_mday;
921         now->hour = lt->tm_hour;
922         now->min  = lt->tm_min;
923         now->sec  = lt->tm_sec;
924     }
925 
926     return( ret );
927 }
928 
929 /*
930  * Return 0 if before <= after, 1 otherwise
931  */
x509_check_time(const mbedtls_x509_time * before,const mbedtls_x509_time * after)932 static int x509_check_time( const mbedtls_x509_time *before, const mbedtls_x509_time *after )
933 {
934 #if defined(VENDOR_CUSTOMISE_CHECK_CERT_DATE_C)
935     if (polarssl_get_checktime() == 0) {
936         return 0;
937     }
938 #endif
939 
940     if( before->year  > after->year )
941         return( 1 );
942 
943     if( before->year == after->year &&
944         before->mon   > after->mon )
945         return( 1 );
946 
947     if( before->year == after->year &&
948         before->mon  == after->mon  &&
949         before->day   > after->day )
950         return( 1 );
951 
952     if( before->year == after->year &&
953         before->mon  == after->mon  &&
954         before->day  == after->day  &&
955         before->hour  > after->hour )
956         return( 1 );
957 
958     if( before->year == after->year &&
959         before->mon  == after->mon  &&
960         before->day  == after->day  &&
961         before->hour == after->hour &&
962         before->min   > after->min  )
963         return( 1 );
964 
965     if( before->year == after->year &&
966         before->mon  == after->mon  &&
967         before->day  == after->day  &&
968         before->hour == after->hour &&
969         before->min  == after->min  &&
970         before->sec   > after->sec  )
971         return( 1 );
972 
973     return( 0 );
974 }
975 
mbedtls_x509_time_is_past(const mbedtls_x509_time * to)976 int mbedtls_x509_time_is_past( const mbedtls_x509_time *to )
977 {
978     mbedtls_x509_time now;
979 
980     if( x509_get_current_time( &now ) != 0 )
981         return( 1 );
982 
983     return( x509_check_time( &now, to ) );
984 }
985 
mbedtls_x509_time_is_future(const mbedtls_x509_time * from)986 int mbedtls_x509_time_is_future( const mbedtls_x509_time *from )
987 {
988     mbedtls_x509_time now;
989 
990     if( x509_get_current_time( &now ) != 0 )
991         return( 1 );
992 
993     return( x509_check_time( from, &now ) );
994 }
995 
996 #else  /* MBEDTLS_HAVE_TIME_DATE */
997 
mbedtls_x509_time_is_past(const mbedtls_x509_time * to)998 int mbedtls_x509_time_is_past( const mbedtls_x509_time *to )
999 {
1000     ((void) to);
1001     return( 0 );
1002 }
1003 
mbedtls_x509_time_is_future(const mbedtls_x509_time * from)1004 int mbedtls_x509_time_is_future( const mbedtls_x509_time *from )
1005 {
1006     ((void) from);
1007     return( 0 );
1008 }
1009 #endif /* MBEDTLS_HAVE_TIME_DATE */
1010 #endif /* MBEDTLS_X509_USE_C */
1011