asn1.h

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/*
 *  Copyright The Mbed TLS Contributors
 *  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.
 */
#ifndef MBEDTLS_ASN1_H
#define MBEDTLS_ASN1_H
#include "mbedtls/private_access.h"

#include "mbedtls/build_info.h"

#include <stddef.h>

#if defined(MBEDTLS_BIGNUM_C)
#include "mbedtls/bignum.h"
#endif

#define MBEDTLS_ERR_ASN1_OUT_OF_DATA                      -0x0060

#define MBEDTLS_ERR_ASN1_UNEXPECTED_TAG                   -0x0062

#define MBEDTLS_ERR_ASN1_INVALID_LENGTH                   -0x0064

#define MBEDTLS_ERR_ASN1_LENGTH_MISMATCH                  -0x0066

#define MBEDTLS_ERR_ASN1_INVALID_DATA                     -0x0068

#define MBEDTLS_ERR_ASN1_ALLOC_FAILED                     -0x006A

#define MBEDTLS_ERR_ASN1_BUF_TOO_SMALL                    -0x006C

/* \} name */

#define MBEDTLS_ASN1_BOOLEAN                 0x01
#define MBEDTLS_ASN1_INTEGER                 0x02
#define MBEDTLS_ASN1_BIT_STRING              0x03
#define MBEDTLS_ASN1_OCTET_STRING            0x04
#define MBEDTLS_ASN1_NULL                    0x05
#define MBEDTLS_ASN1_OID                     0x06
#define MBEDTLS_ASN1_ENUMERATED              0x0A
#define MBEDTLS_ASN1_UTF8_STRING             0x0C
#define MBEDTLS_ASN1_SEQUENCE                0x10
#define MBEDTLS_ASN1_SET                     0x11
#define MBEDTLS_ASN1_PRINTABLE_STRING        0x13
#define MBEDTLS_ASN1_T61_STRING              0x14
#define MBEDTLS_ASN1_IA5_STRING              0x16
#define MBEDTLS_ASN1_UTC_TIME                0x17
#define MBEDTLS_ASN1_GENERALIZED_TIME        0x18
#define MBEDTLS_ASN1_UNIVERSAL_STRING        0x1C
#define MBEDTLS_ASN1_BMP_STRING              0x1E
#define MBEDTLS_ASN1_PRIMITIVE               0x00
#define MBEDTLS_ASN1_CONSTRUCTED             0x20
#define MBEDTLS_ASN1_CONTEXT_SPECIFIC        0x80

/* Slightly smaller way to check if tag is a string tag
 * compared to canonical implementation. */
#define MBEDTLS_ASN1_IS_STRING_TAG( tag )                                     \
    ( ( tag ) < 32u && (                                                      \
        ( ( 1u << ( tag ) ) & ( ( 1u << MBEDTLS_ASN1_BMP_STRING )       |     \
                                ( 1u << MBEDTLS_ASN1_UTF8_STRING )      |     \
                                ( 1u << MBEDTLS_ASN1_T61_STRING )       |     \
                                ( 1u << MBEDTLS_ASN1_IA5_STRING )       |     \
                                ( 1u << MBEDTLS_ASN1_UNIVERSAL_STRING ) |     \
                                ( 1u << MBEDTLS_ASN1_PRINTABLE_STRING ) |     \
                                ( 1u << MBEDTLS_ASN1_BIT_STRING ) ) ) != 0 ) )

/*
 * Bit masks for each of the components of an ASN.1 tag as specified in
 * ITU X.690 (08/2015), section 8.1 "General rules for encoding",
 * paragraph 8.1.2.2:
 *
 * Bit  8     7   6   5          1
 *     +-------+-----+------------+
 *     | Class | P/C | Tag number |
 *     +-------+-----+------------+
 */
#define MBEDTLS_ASN1_TAG_CLASS_MASK          0xC0
#define MBEDTLS_ASN1_TAG_PC_MASK             0x20
#define MBEDTLS_ASN1_TAG_VALUE_MASK          0x1F

/* \} name */
/* \} addtogroup asn1_module */

#define MBEDTLS_OID_SIZE(x) (sizeof(x) - 1)

#define MBEDTLS_OID_CMP(oid_str, oid_buf)                                   \
        ( ( MBEDTLS_OID_SIZE(oid_str) != (oid_buf)->len ) ||                \
          memcmp( (oid_str), (oid_buf)->p, (oid_buf)->len) != 0 )

#define MBEDTLS_OID_CMP_RAW(oid_str, oid_buf, oid_buf_len)              \
        ( ( MBEDTLS_OID_SIZE(oid_str) != (oid_buf_len) ) ||             \
          memcmp( (oid_str), (oid_buf), (oid_buf_len) ) != 0 )

#ifdef __cplusplus
extern "C" {
#endif

typedef struct mbedtls_asn1_buf
{
    int tag;                
    size_t len;             
    unsigned char *p;       
}
mbedtls_asn1_buf;

typedef struct mbedtls_asn1_bitstring
{
    size_t len;                 
    unsigned char unused_bits;  
    unsigned char *p;           
}
mbedtls_asn1_bitstring;

typedef struct mbedtls_asn1_sequence
{
    mbedtls_asn1_buf buf;                   
    struct mbedtls_asn1_sequence *next;
}
mbedtls_asn1_sequence;

typedef struct mbedtls_asn1_named_data
{
    mbedtls_asn1_buf oid;                   
    mbedtls_asn1_buf val;                   
    struct mbedtls_asn1_named_data *next;

    unsigned char MBEDTLS_PRIVATE(next_merged);
}
mbedtls_asn1_named_data;

int mbedtls_asn1_get_len( unsigned char **p,
                          const unsigned char *end,
                          size_t *len );

int mbedtls_asn1_get_tag( unsigned char **p,
                          const unsigned char *end,
                          size_t *len, int tag );

int mbedtls_asn1_get_bool( unsigned char **p,
                           const unsigned char *end,
                           int *val );

int mbedtls_asn1_get_int( unsigned char **p,
                          const unsigned char *end,
                          int *val );

int mbedtls_asn1_get_enum( unsigned char **p,
                           const unsigned char *end,
                           int *val );

int mbedtls_asn1_get_bitstring( unsigned char **p, const unsigned char *end,
                                mbedtls_asn1_bitstring *bs );

int mbedtls_asn1_get_bitstring_null( unsigned char **p,
                                     const unsigned char *end,
                                     size_t *len );

int mbedtls_asn1_get_sequence_of( unsigned char **p,
                                  const unsigned char *end,
                                  mbedtls_asn1_sequence *cur,
                                  int tag );
void mbedtls_asn1_sequence_free( mbedtls_asn1_sequence *seq );

int mbedtls_asn1_traverse_sequence_of(
    unsigned char **p,
    const unsigned char *end,
    unsigned char tag_must_mask, unsigned char tag_must_val,
    unsigned char tag_may_mask, unsigned char tag_may_val,
    int (*cb)( void *ctx, int tag,
               unsigned char* start, size_t len ),
    void *ctx );

#if defined(MBEDTLS_BIGNUM_C)

int mbedtls_asn1_get_mpi( unsigned char **p,
                          const unsigned char *end,
                          mbedtls_mpi *X );
#endif /* MBEDTLS_BIGNUM_C */

int mbedtls_asn1_get_alg( unsigned char **p,
                  const unsigned char *end,
                  mbedtls_asn1_buf *alg, mbedtls_asn1_buf *params );

int mbedtls_asn1_get_alg_null( unsigned char **p,
                       const unsigned char *end,
                       mbedtls_asn1_buf *alg );

const mbedtls_asn1_named_data *mbedtls_asn1_find_named_data( const mbedtls_asn1_named_data *list,
                                       const char *oid, size_t len );

void mbedtls_asn1_free_named_data( mbedtls_asn1_named_data *entry );

void mbedtls_asn1_free_named_data_list( mbedtls_asn1_named_data **head );

#ifdef __cplusplus
}
#endif

#endif /* asn1.h */