Mbed OS Reference | crypto_struct

 /**
  * \file psa/crypto_struct.h
  *
  * \brief PSA cryptography module: Mbed TLS structured type implementations
  *
  * \note This file may not be included directly. Applications must
  * include psa/crypto.h.
  *
  * This file contains the definitions of some data structures with
  * implementation-specific definitions.
  *
  * In implementations with isolation between the application and the
  * cryptography module, it is expected that the front-end and the back-end
  * would have different versions of this file.
  *
  * <h3>Design notes about multipart operation structures</h3>
  *
  * Each multipart operation structure contains a `psa_algorithm_t alg`
  * field which indicates which specific algorithm the structure is for.
  * When the structure is not in use, `alg` is 0. Most of the structure
  * consists of a union which is discriminated by `alg`.
  *
  * Note that when `alg` is 0, the content of other fields is undefined.
  * In particular, it is not guaranteed that a freshly-initialized structure
  * is all-zero: we initialize structures to something like `{0, 0}`, which
  * is only guaranteed to initializes the first member of the union;
  * GCC and Clang initialize the whole structure to 0 (at the time of writing),
  * but MSVC and CompCert don't.
  *
  * In Mbed Crypto, multipart operation structures live independently from
  * the key. This allows Mbed Crypto to free the key objects when destroying
  * a key slot. If a multipart operation needs to remember the key after
  * the setup function returns, the operation structure needs to contain a
  * copy of the key.
  */
 /*
  *  Copyright (C) 2018, 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)
  */
 
 #ifndef PSA_CRYPTO_STRUCT_H
 #define PSA_CRYPTO_STRUCT_H
 
 #include "psa/client.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 struct psa_hash_operation_s {
     psa_handle_t handle;
 };
 
 #define PSA_HASH_OPERATION_INIT { PSA_NULL_HANDLE }
 static inline struct psa_hash_operation_s psa_hash_operation_init( void )
 {
     const struct psa_hash_operation_s v = PSA_HASH_OPERATION_INIT;
     return( v );
 }
 
 struct psa_mac_operation_s
 {
     psa_handle_t handle;
 };
 
 #define PSA_MAC_OPERATION_INIT { PSA_NULL_HANDLE }
 static inline struct psa_mac_operation_s psa_mac_operation_init( void )
 {
     const struct psa_mac_operation_s v = PSA_MAC_OPERATION_INIT;
     return( v );
 }
 
 struct psa_cipher_operation_s
 {
     psa_handle_t handle;
 };
 
 #define PSA_CIPHER_OPERATION_INIT { PSA_NULL_HANDLE }
 static inline struct psa_cipher_operation_s psa_cipher_operation_init( void )
 {
     const struct psa_cipher_operation_s v = PSA_CIPHER_OPERATION_INIT;
     return( v );
 }
 
 struct psa_aead_operation_s
 {
     psa_handle_t handle;
 };
 
 #define PSA_AEAD_OPERATION_INIT { PSA_NULL_HANDLE }
 static inline struct psa_aead_operation_s psa_aead_operation_init( void )
 {
     const struct psa_aead_operation_s v = PSA_AEAD_OPERATION_INIT;
     return( v );
 }
 
 struct psa_key_derivation_s
 {
     psa_handle_t handle;
 };
 
 /* This only zeroes out the first byte in the union, the rest is unspecified. */
 #define PSA_KEY_DERIVATION_OPERATION_INIT { PSA_NULL_HANDLE }
 static inline struct psa_key_derivation_s psa_key_derivation_operation_init( void )
 {
     const struct psa_key_derivation_s v = PSA_KEY_DERIVATION_OPERATION_INIT;
     return( v );
 }
 
 struct psa_key_policy_s
 {
     psa_key_usage_t usage;
     psa_algorithm_t alg;
     psa_algorithm_t alg2;
 };
 typedef struct psa_key_policy_s psa_key_policy_t;
 
 #define PSA_KEY_POLICY_INIT {0, 0, 0}
 static inline struct psa_key_policy_s psa_key_policy_init( void )
 {
     const struct psa_key_policy_s v = PSA_KEY_POLICY_INIT;
     return( v );
 }
 
 /* The type used internally for key sizes.
  * Public interfaces use size_t, but internally we use a smaller type. */
 typedef uint16_t psa_key_bits_t;
 /* The maximum value of the type used to represent bit-sizes.
  * This is used to mark an invalid key size. */
 #define PSA_KEY_BITS_TOO_LARGE ( (psa_key_bits_t) ( -1 ) )
 /* The maximum size of a key in bits.
  * Currently defined as the maximum that can be represented, rounded down
  * to a whole number of bytes.
  * This is an uncast value so that it can be used in preprocessor
  * conditionals. */
 #define PSA_MAX_KEY_BITS 0xfff8
 
 /** A mask of flags that can be stored in key attributes.
  *
  * This type is also used internally to store flags in slots. Internal
  * flags are defined in library/psa_crypto_core.h. Internal flags may have
  * the same value as external flags if they are properly handled during
  * key creation and in psa_get_key_attributes.
  */
 typedef uint16_t psa_key_attributes_flag_t;
 
 #define MBEDTLS_PSA_KA_FLAG_HAS_SLOT_NUMBER     \
     ( (psa_key_attributes_flag_t) 0x0001 )
 
 /* A mask of key attribute flags used externally only.
  * Only meant for internal checks inside the library. */
 #define MBEDTLS_PSA_KA_MASK_EXTERNAL_ONLY (      \
         MBEDTLS_PSA_KA_FLAG_HAS_SLOT_NUMBER |    \
         0 )
 
 /* A mask of key attribute flags used both internally and externally.
  * Currently there aren't any. */
 #define MBEDTLS_PSA_KA_MASK_DUAL_USE (          \
         0 )
 
 typedef struct
 {
     psa_key_type_t type;
     psa_key_lifetime_t lifetime;
     psa_key_id_t id;
     psa_key_policy_t policy;
     psa_key_bits_t bits;
     psa_key_attributes_flag_t flags;
 } psa_core_key_attributes_t;
 
 #define PSA_CORE_KEY_ATTRIBUTES_INIT {0, 0, PSA_KEY_ID_INIT, PSA_KEY_POLICY_INIT, 0, 0}
 
 struct psa_key_attributes_s
 {
     psa_core_key_attributes_t core;
 #if defined(MBEDTLS_PSA_CRYPTO_SE_C)
     psa_key_slot_number_t slot_number;
 #endif /* MBEDTLS_PSA_CRYPTO_SE_C */
     void *domain_parameters;
     size_t domain_parameters_size;
 };
 
 #if defined(MBEDTLS_PSA_CRYPTO_SE_C)
 #define PSA_KEY_ATTRIBUTES_INIT {PSA_CORE_KEY_ATTRIBUTES_INIT, 0, NULL, 0}
 #else
 #define PSA_KEY_ATTRIBUTES_INIT {PSA_CORE_KEY_ATTRIBUTES_INIT, NULL, 0}
 #endif
 
 static inline struct psa_key_attributes_s psa_key_attributes_init( void )
 {
     const struct psa_key_attributes_s v = PSA_KEY_ATTRIBUTES_INIT;
     return( v );
 }
 
 static inline void psa_set_key_id(psa_key_attributes_t *attributes,
                                   psa_key_id_t id)
 {
     attributes->core.id = id;
     if( attributes->core.lifetime == PSA_KEY_LIFETIME_VOLATILE )
         attributes->core.lifetime = PSA_KEY_LIFETIME_PERSISTENT;
 }
 
 static inline psa_key_id_t psa_get_key_id(
     const psa_key_attributes_t *attributes)
 {
     return( attributes->core.id );
 }
 
 static inline void psa_set_key_lifetime(psa_key_attributes_t *attributes,
                                         psa_key_lifetime_t lifetime)
 {
     attributes->core.lifetime = lifetime;
     if( lifetime == PSA_KEY_LIFETIME_VOLATILE )
     {
 #ifdef MBEDTLS_PSA_CRYPTO_KEY_FILE_ID_ENCODES_OWNER
         attributes->core.id.key_id = 0;
         attributes->core.id.owner = 0;
 #else
         attributes->core.id = 0;
 #endif
     }
 }
 
 static inline psa_key_lifetime_t psa_get_key_lifetime(
     const psa_key_attributes_t *attributes)
 {
     return( attributes->core.lifetime );
 }
 
 static inline void psa_set_key_usage_flags(psa_key_attributes_t *attributes,
                                            psa_key_usage_t usage_flags)
 {
     attributes->core.policy.usage = usage_flags;
 }
 
 static inline psa_key_usage_t psa_get_key_usage_flags(
     const psa_key_attributes_t *attributes)
 {
     return( attributes->core.policy.usage );
 }
 
 static inline void psa_set_key_algorithm(psa_key_attributes_t *attributes,
                                          psa_algorithm_t alg)
 {
     attributes->core.policy.alg = alg;
 }
 
 static inline psa_algorithm_t psa_get_key_algorithm(
     const psa_key_attributes_t *attributes)
 {
     return( attributes->core.policy.alg );
 }
 
 /* This function is declared in crypto_extra.h, which comes after this
  * header file, but we need the function here, so repeat the declaration. */
 psa_status_t psa_set_key_domain_parameters(psa_key_attributes_t *attributes,
                                            psa_key_type_t type,
                                            const uint8_t *data,
                                            size_t data_length);
 
 static inline void psa_set_key_type(psa_key_attributes_t *attributes,
                                     psa_key_type_t type)
 {
     if( attributes->domain_parameters == NULL )
     {
         /* Common case: quick path */
         attributes->core.type = type;
     }
     else
     {
         /* Call the bigger function to free the old domain paramteres.
          * Ignore any errors which may arise due to type requiring
          * non-default domain parameters, since this function can't
          * report errors. */
         (void) psa_set_key_domain_parameters( attributes, type, NULL, 0 );
     }
 }
 
 static inline psa_key_type_t psa_get_key_type(
     const psa_key_attributes_t *attributes)
 {
     return( attributes->core.type );
 }
 
 static inline void psa_set_key_bits(psa_key_attributes_t *attributes,
                                     size_t bits)
 {
     if( bits > PSA_MAX_KEY_BITS )
         attributes->core.bits = PSA_KEY_BITS_TOO_LARGE;
     else
         attributes->core.bits = (psa_key_bits_t) bits;
 }
 
 static inline size_t psa_get_key_bits(
     const psa_key_attributes_t *attributes)
 {
     return( attributes->core.bits );
 }
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif /* PSA_CRYPTO_STRUCT_H */
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