394 lines
		
	
	
		
			9.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			394 lines
		
	
	
		
			9.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|  | /*
 | ||
|  |  *  Generic ASN.1 parsing | ||
|  |  * | ||
|  |  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved | ||
|  |  *  SPDX-License-Identifier: Apache-2.0 | ||
|  |  * | ||
|  |  *  Licensed under the Apache License, Version 2.0 (the "License"); you may | ||
|  |  *  not use this file except in compliance with the License. | ||
|  |  *  You may obtain a copy of the License at | ||
|  |  * | ||
|  |  *  http://www.apache.org/licenses/LICENSE-2.0
 | ||
|  |  * | ||
|  |  *  Unless required by applicable law or agreed to in writing, software | ||
|  |  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT | ||
|  |  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
|  |  *  See the License for the specific language governing permissions and | ||
|  |  *  limitations under the License. | ||
|  |  * | ||
|  |  *  This file is part of mbed TLS (https://tls.mbed.org)
 | ||
|  |  */ | ||
|  | 
 | ||
|  | #if !defined(MBEDTLS_CONFIG_FILE)
 | ||
|  | #include "mbedtls/config.h"
 | ||
|  | #else
 | ||
|  | #include MBEDTLS_CONFIG_FILE
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_ASN1_PARSE_C)
 | ||
|  | 
 | ||
|  | #include "mbedtls/asn1.h"
 | ||
|  | 
 | ||
|  | #include <string.h>
 | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_BIGNUM_C)
 | ||
|  | #include "mbedtls/bignum.h"
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PLATFORM_C)
 | ||
|  | #include "mbedtls/platform.h"
 | ||
|  | #else
 | ||
|  | #include <stdlib.h>
 | ||
|  | #define mbedtls_calloc    calloc
 | ||
|  | #define mbedtls_free       free
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | /* Implementation that should never be optimized out by the compiler */ | ||
|  | static void mbedtls_zeroize( void *v, size_t n ) { | ||
|  |     volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0; | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * ASN.1 DER decoding routines | ||
|  |  */ | ||
|  | int mbedtls_asn1_get_len( unsigned char **p, | ||
|  |                   const unsigned char *end, | ||
|  |                   size_t *len ) | ||
|  | { | ||
|  |     if( ( end - *p ) < 1 ) | ||
|  |         return( MBEDTLS_ERR_ASN1_OUT_OF_DATA ); | ||
|  | 
 | ||
|  |     if( ( **p & 0x80 ) == 0 ) | ||
|  |         *len = *(*p)++; | ||
|  |     else | ||
|  |     { | ||
|  |         switch( **p & 0x7F ) | ||
|  |         { | ||
|  |         case 1: | ||
|  |             if( ( end - *p ) < 2 ) | ||
|  |                 return( MBEDTLS_ERR_ASN1_OUT_OF_DATA ); | ||
|  | 
 | ||
|  |             *len = (*p)[1]; | ||
|  |             (*p) += 2; | ||
|  |             break; | ||
|  | 
 | ||
|  |         case 2: | ||
|  |             if( ( end - *p ) < 3 ) | ||
|  |                 return( MBEDTLS_ERR_ASN1_OUT_OF_DATA ); | ||
|  | 
 | ||
|  |             *len = ( (size_t)(*p)[1] << 8 ) | (*p)[2]; | ||
|  |             (*p) += 3; | ||
|  |             break; | ||
|  | 
 | ||
|  |         case 3: | ||
|  |             if( ( end - *p ) < 4 ) | ||
|  |                 return( MBEDTLS_ERR_ASN1_OUT_OF_DATA ); | ||
|  | 
 | ||
|  |             *len = ( (size_t)(*p)[1] << 16 ) | | ||
|  |                    ( (size_t)(*p)[2] << 8  ) | (*p)[3]; | ||
|  |             (*p) += 4; | ||
|  |             break; | ||
|  | 
 | ||
|  |         case 4: | ||
|  |             if( ( end - *p ) < 5 ) | ||
|  |                 return( MBEDTLS_ERR_ASN1_OUT_OF_DATA ); | ||
|  | 
 | ||
|  |             *len = ( (size_t)(*p)[1] << 24 ) | ( (size_t)(*p)[2] << 16 ) | | ||
|  |                    ( (size_t)(*p)[3] << 8  ) |           (*p)[4]; | ||
|  |             (*p) += 5; | ||
|  |             break; | ||
|  | 
 | ||
|  |         default: | ||
|  |             return( MBEDTLS_ERR_ASN1_INVALID_LENGTH ); | ||
|  |         } | ||
|  |     } | ||
|  | 
 | ||
|  |     if( *len > (size_t) ( end - *p ) ) | ||
|  |         return( MBEDTLS_ERR_ASN1_OUT_OF_DATA ); | ||
|  | 
 | ||
|  |     return( 0 ); | ||
|  | } | ||
|  | 
 | ||
|  | int mbedtls_asn1_get_tag( unsigned char **p, | ||
|  |                   const unsigned char *end, | ||
|  |                   size_t *len, int tag ) | ||
|  | { | ||
|  |     if( ( end - *p ) < 1 ) | ||
|  |         return( MBEDTLS_ERR_ASN1_OUT_OF_DATA ); | ||
|  | 
 | ||
|  |     if( **p != tag ) | ||
|  |         return( MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ); | ||
|  | 
 | ||
|  |     (*p)++; | ||
|  | 
 | ||
|  |     return( mbedtls_asn1_get_len( p, end, len ) ); | ||
|  | } | ||
|  | 
 | ||
|  | int mbedtls_asn1_get_bool( unsigned char **p, | ||
|  |                    const unsigned char *end, | ||
|  |                    int *val ) | ||
|  | { | ||
|  |     int ret; | ||
|  |     size_t len; | ||
|  | 
 | ||
|  |     if( ( ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_BOOLEAN ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     if( len != 1 ) | ||
|  |         return( MBEDTLS_ERR_ASN1_INVALID_LENGTH ); | ||
|  | 
 | ||
|  |     *val = ( **p != 0 ) ? 1 : 0; | ||
|  |     (*p)++; | ||
|  | 
 | ||
|  |     return( 0 ); | ||
|  | } | ||
|  | 
 | ||
|  | int mbedtls_asn1_get_int( unsigned char **p, | ||
|  |                   const unsigned char *end, | ||
|  |                   int *val ) | ||
|  | { | ||
|  |     int ret; | ||
|  |     size_t len; | ||
|  | 
 | ||
|  |     if( ( ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_INTEGER ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     if( len == 0 || len > sizeof( int ) || ( **p & 0x80 ) != 0 ) | ||
|  |         return( MBEDTLS_ERR_ASN1_INVALID_LENGTH ); | ||
|  | 
 | ||
|  |     *val = 0; | ||
|  | 
 | ||
|  |     while( len-- > 0 ) | ||
|  |     { | ||
|  |         *val = ( *val << 8 ) | **p; | ||
|  |         (*p)++; | ||
|  |     } | ||
|  | 
 | ||
|  |     return( 0 ); | ||
|  | } | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_BIGNUM_C)
 | ||
|  | int mbedtls_asn1_get_mpi( unsigned char **p, | ||
|  |                   const unsigned char *end, | ||
|  |                   mbedtls_mpi *X ) | ||
|  | { | ||
|  |     int ret; | ||
|  |     size_t len; | ||
|  | 
 | ||
|  |     if( ( ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_INTEGER ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     ret = mbedtls_mpi_read_binary( X, *p, len ); | ||
|  | 
 | ||
|  |     *p += len; | ||
|  | 
 | ||
|  |     return( ret ); | ||
|  | } | ||
|  | #endif /* MBEDTLS_BIGNUM_C */
 | ||
|  | 
 | ||
|  | int mbedtls_asn1_get_bitstring( unsigned char **p, const unsigned char *end, | ||
|  |                         mbedtls_asn1_bitstring *bs) | ||
|  | { | ||
|  |     int ret; | ||
|  | 
 | ||
|  |     /* Certificate type is a single byte bitstring */ | ||
|  |     if( ( ret = mbedtls_asn1_get_tag( p, end, &bs->len, MBEDTLS_ASN1_BIT_STRING ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     /* Check length, subtract one for actual bit string length */ | ||
|  |     if( bs->len < 1 ) | ||
|  |         return( MBEDTLS_ERR_ASN1_OUT_OF_DATA ); | ||
|  |     bs->len -= 1; | ||
|  | 
 | ||
|  |     /* Get number of unused bits, ensure unused bits <= 7 */ | ||
|  |     bs->unused_bits = **p; | ||
|  |     if( bs->unused_bits > 7 ) | ||
|  |         return( MBEDTLS_ERR_ASN1_INVALID_LENGTH ); | ||
|  |     (*p)++; | ||
|  | 
 | ||
|  |     /* Get actual bitstring */ | ||
|  |     bs->p = *p; | ||
|  |     *p += bs->len; | ||
|  | 
 | ||
|  |     if( *p != end ) | ||
|  |         return( MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ); | ||
|  | 
 | ||
|  |     return( 0 ); | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Get a bit string without unused bits | ||
|  |  */ | ||
|  | int mbedtls_asn1_get_bitstring_null( unsigned char **p, const unsigned char *end, | ||
|  |                              size_t *len ) | ||
|  | { | ||
|  |     int ret; | ||
|  | 
 | ||
|  |     if( ( ret = mbedtls_asn1_get_tag( p, end, len, MBEDTLS_ASN1_BIT_STRING ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     if( (*len)-- < 2 || *(*p)++ != 0 ) | ||
|  |         return( MBEDTLS_ERR_ASN1_INVALID_DATA ); | ||
|  | 
 | ||
|  |     return( 0 ); | ||
|  | } | ||
|  | 
 | ||
|  | 
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  *  Parses and splits an ASN.1 "SEQUENCE OF <tag>" | ||
|  |  */ | ||
|  | int mbedtls_asn1_get_sequence_of( unsigned char **p, | ||
|  |                           const unsigned char *end, | ||
|  |                           mbedtls_asn1_sequence *cur, | ||
|  |                           int tag) | ||
|  | { | ||
|  |     int ret; | ||
|  |     size_t len; | ||
|  |     mbedtls_asn1_buf *buf; | ||
|  | 
 | ||
|  |     /* Get main sequence tag */ | ||
|  |     if( ( ret = mbedtls_asn1_get_tag( p, end, &len, | ||
|  |             MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     if( *p + len != end ) | ||
|  |         return( MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ); | ||
|  | 
 | ||
|  |     while( *p < end ) | ||
|  |     { | ||
|  |         buf = &(cur->buf); | ||
|  |         buf->tag = **p; | ||
|  | 
 | ||
|  |         if( ( ret = mbedtls_asn1_get_tag( p, end, &buf->len, tag ) ) != 0 ) | ||
|  |             return( ret ); | ||
|  | 
 | ||
|  |         buf->p = *p; | ||
|  |         *p += buf->len; | ||
|  | 
 | ||
|  |         /* Allocate and assign next pointer */ | ||
|  |         if( *p < end ) | ||
|  |         { | ||
|  |             cur->next = (mbedtls_asn1_sequence*)mbedtls_calloc( 1, | ||
|  |                                             sizeof( mbedtls_asn1_sequence ) ); | ||
|  | 
 | ||
|  |             if( cur->next == NULL ) | ||
|  |                 return( MBEDTLS_ERR_ASN1_ALLOC_FAILED ); | ||
|  | 
 | ||
|  |             cur = cur->next; | ||
|  |         } | ||
|  |     } | ||
|  | 
 | ||
|  |     /* Set final sequence entry's next pointer to NULL */ | ||
|  |     cur->next = NULL; | ||
|  | 
 | ||
|  |     if( *p != end ) | ||
|  |         return( MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ); | ||
|  | 
 | ||
|  |     return( 0 ); | ||
|  | } | ||
|  | 
 | ||
|  | int mbedtls_asn1_get_alg( unsigned char **p, | ||
|  |                   const unsigned char *end, | ||
|  |                   mbedtls_asn1_buf *alg, mbedtls_asn1_buf *params ) | ||
|  | { | ||
|  |     int ret; | ||
|  |     size_t len; | ||
|  | 
 | ||
|  |     if( ( ret = mbedtls_asn1_get_tag( p, end, &len, | ||
|  |             MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     if( ( end - *p ) < 1 ) | ||
|  |         return( MBEDTLS_ERR_ASN1_OUT_OF_DATA ); | ||
|  | 
 | ||
|  |     alg->tag = **p; | ||
|  |     end = *p + len; | ||
|  | 
 | ||
|  |     if( ( ret = mbedtls_asn1_get_tag( p, end, &alg->len, MBEDTLS_ASN1_OID ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     alg->p = *p; | ||
|  |     *p += alg->len; | ||
|  | 
 | ||
|  |     if( *p == end ) | ||
|  |     { | ||
|  |         mbedtls_zeroize( params, sizeof(mbedtls_asn1_buf) ); | ||
|  |         return( 0 ); | ||
|  |     } | ||
|  | 
 | ||
|  |     params->tag = **p; | ||
|  |     (*p)++; | ||
|  | 
 | ||
|  |     if( ( ret = mbedtls_asn1_get_len( p, end, ¶ms->len ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     params->p = *p; | ||
|  |     *p += params->len; | ||
|  | 
 | ||
|  |     if( *p != end ) | ||
|  |         return( MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ); | ||
|  | 
 | ||
|  |     return( 0 ); | ||
|  | } | ||
|  | 
 | ||
|  | int mbedtls_asn1_get_alg_null( unsigned char **p, | ||
|  |                        const unsigned char *end, | ||
|  |                        mbedtls_asn1_buf *alg ) | ||
|  | { | ||
|  |     int ret; | ||
|  |     mbedtls_asn1_buf params; | ||
|  | 
 | ||
|  |     memset( ¶ms, 0, sizeof(mbedtls_asn1_buf) ); | ||
|  | 
 | ||
|  |     if( ( ret = mbedtls_asn1_get_alg( p, end, alg, ¶ms ) ) != 0 ) | ||
|  |         return( ret ); | ||
|  | 
 | ||
|  |     if( ( params.tag != MBEDTLS_ASN1_NULL && params.tag != 0 ) || params.len != 0 ) | ||
|  |         return( MBEDTLS_ERR_ASN1_INVALID_DATA ); | ||
|  | 
 | ||
|  |     return( 0 ); | ||
|  | } | ||
|  | 
 | ||
|  | void mbedtls_asn1_free_named_data( mbedtls_asn1_named_data *cur ) | ||
|  | { | ||
|  |     if( cur == NULL ) | ||
|  |         return; | ||
|  | 
 | ||
|  |     mbedtls_free( cur->oid.p ); | ||
|  |     mbedtls_free( cur->val.p ); | ||
|  | 
 | ||
|  |     mbedtls_zeroize( cur, sizeof( mbedtls_asn1_named_data ) ); | ||
|  | } | ||
|  | 
 | ||
|  | void mbedtls_asn1_free_named_data_list( mbedtls_asn1_named_data **head ) | ||
|  | { | ||
|  |     mbedtls_asn1_named_data *cur; | ||
|  | 
 | ||
|  |     while( ( cur = *head ) != NULL ) | ||
|  |     { | ||
|  |         *head = cur->next; | ||
|  |         mbedtls_asn1_free_named_data( cur ); | ||
|  |         mbedtls_free( cur ); | ||
|  |     } | ||
|  | } | ||
|  | 
 | ||
|  | mbedtls_asn1_named_data *mbedtls_asn1_find_named_data( mbedtls_asn1_named_data *list, | ||
|  |                                        const char *oid, size_t len ) | ||
|  | { | ||
|  |     while( list != NULL ) | ||
|  |     { | ||
|  |         if( list->oid.len == len && | ||
|  |             memcmp( list->oid.p, oid, len ) == 0 ) | ||
|  |         { | ||
|  |             break; | ||
|  |         } | ||
|  | 
 | ||
|  |         list = list->next; | ||
|  |     } | ||
|  | 
 | ||
|  |     return( list ); | ||
|  | } | ||
|  | 
 | ||
|  | #endif /* MBEDTLS_ASN1_PARSE_C */
 |