/*
* PSA crypto core internal interfaces
*/
/*
* 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 PSA_CRYPTO_CORE_H
#define PSA_CRYPTO_CORE_H
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#include "psa/crypto.h"
#include "psa/crypto_se_driver.h"
#include <mbedtls/md_internal.h>
/** The data structure representing a key slot, containing key material
* and metadata for one key.
*/
typedef struct {
psa_core_key_attributes_t attr;
/*
* Number of locks on the key slot held by the library.
*
* This counter is incremented by one each time a library function
* retrieves through one of the dedicated internal API a pointer to the
* key slot.
*
* This counter is decremented by one each time a library function stops
* accessing the key slot and states it by calling the
* psa_unlock_key_slot() API.
*
* This counter is used to prevent resetting the key slot while the library
* may access it. For example, such control is needed in the following
* scenarios:
* . In case of key slot starvation, all key slots contain the description
* of a key, and the library asks for the description of a persistent
* key not present in the key slots, the key slots currently accessed by
* the library cannot be reclaimed to free a key slot to load the
* persistent key.
* . In case of a multi-threaded application where one thread asks to close
* or purge or destroy a key while it is in used by the library through
* another thread.
*/
size_t lock_count;
/* Dynamically allocated key data buffer.
* Format as specified in psa_export_key(). */
struct key_data {
uint8_t *data;
size_t bytes;
} key;
} psa_key_slot_t;
/* A mask of key attribute flags used only internally.
* Currently there aren't any. */
#define PSA_KA_MASK_INTERNAL_ONLY ( \
0 )
/** Test whether a key slot is occupied.
*
* A key slot is occupied iff the key type is nonzero. This works because
* no valid key can have 0 as its key type.
*
* \param[in] slot The key slot to test.
*
* \return 1 if the slot is occupied, 0 otherwise.
*/
static inline int psa_is_key_slot_occupied(const psa_key_slot_t *slot) {
return (slot->attr.type != 0);
}
/** Test whether a key slot is locked.
*
* A key slot is locked iff its lock counter is strictly greater than 0.
*
* \param[in] slot The key slot to test.
*
* \return 1 if the slot is locked, 0 otherwise.
*/
static inline int psa_is_key_slot_locked(const psa_key_slot_t *slot) {
return (slot->lock_count > 0);
}
/** Retrieve flags from psa_key_slot_t::attr::core::flags.
*
* \param[in] slot The key slot to query.
* \param mask The mask of bits to extract.
*
* \return The key attribute flags in the given slot,
* bitwise-anded with \p mask.
*/
static inline uint16_t psa_key_slot_get_flags(const psa_key_slot_t *slot,
uint16_t mask) {
return (slot->attr.flags & mask);
}
/** Set flags in psa_key_slot_t::attr::core::flags.
*
* \param[in,out] slot The key slot to modify.
* \param mask The mask of bits to modify.
* \param value The new value of the selected bits.
*/
static inline void psa_key_slot_set_flags(psa_key_slot_t *slot,
uint16_t mask,
uint16_t value) {
slot->attr.flags = ((~mask & slot->attr.flags) |
(mask & value));
}
/** Turn on flags in psa_key_slot_t::attr::core::flags.
*
* \param[in,out] slot The key slot to modify.
* \param mask The mask of bits to set.
*/
static inline void psa_key_slot_set_bits_in_flags(psa_key_slot_t *slot,
uint16_t mask) {
slot->attr.flags |= mask;
}
/** Turn off flags in psa_key_slot_t::attr::core::flags.
*
* \param[in,out] slot The key slot to modify.
* \param mask The mask of bits to clear.
*/
static inline void psa_key_slot_clear_bits(psa_key_slot_t *slot,
uint16_t mask) {
slot->attr.flags &= ~mask;
}
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
/** Get the SE slot number of a key from the key slot storing its description.
*
* \param[in] slot The key slot to query. This must be a key slot storing
* the description of a key of a dynamically registered
* secure element, otherwise the behaviour is undefined.
*/
static inline psa_key_slot_number_t psa_key_slot_get_slot_number(
const psa_key_slot_t *slot) {
return (*((psa_key_slot_number_t *)(slot->key.data)));
}
#endif
/** Completely wipe a slot in memory, including its policy.
*
* Persistent storage is not affected.
*
* \param[in,out] slot The key slot to wipe.
*
* \retval #PSA_SUCCESS
* Success. This includes the case of a key slot that was
* already fully wiped.
* \retval #PSA_ERROR_CORRUPTION_DETECTED
*/
psa_status_t psa_wipe_key_slot(psa_key_slot_t *slot);
/** Copy key data (in export format) into an empty key slot.
*
* This function assumes that the slot does not contain
* any key material yet. On failure, the slot content is unchanged.
*
* \param[in,out] slot Key slot to copy the key into.
* \param[in] data Buffer containing the key material.
* \param data_length Size of the key buffer.
*
* \retval #PSA_SUCCESS
* The key has been copied successfully.
* \retval #PSA_ERROR_INSUFFICIENT_MEMORY
* Not enough memory was available for allocation of the
* copy buffer.
* \retval #PSA_ERROR_ALREADY_EXISTS
* There was other key material already present in the slot.
*/
psa_status_t psa_copy_key_material_into_slot(psa_key_slot_t *slot,
const uint8_t *data,
size_t data_length);
/** Convert an mbed TLS error code to a PSA error code
*
* \note This function is provided solely for the convenience of
* Mbed TLS and may be removed at any time without notice.
*
* \param ret An mbed TLS-thrown error code
*
* \return The corresponding PSA error code
*/
psa_status_t mbedtls_to_psa_error(int ret);
/** Get Mbed TLS MD information of a hash algorithm given its PSA identifier
*
* \param[in] alg PSA hash algorithm identifier
*
* \return The Mbed TLS MD information of the hash algorithm. \c NULL if the
* PSA hash algorithm is not supported.
*/
const mbedtls_md_info_t *mbedtls_md_info_from_psa(psa_algorithm_t alg);
/** Import a key in binary format.
*
* \note The signature of this function is that of a PSA driver
* import_key entry point. This function behaves as an import_key
* entry point as defined in the PSA driver interface specification for
* transparent drivers.
*
* \param[in] attributes The attributes for the key to import.
* \param[in] data The buffer containing the key data in import
* format.
* \param[in] data_length Size of the \p data buffer in bytes.
* \param[out] key_buffer The buffer to contain the key data in output
* format upon successful return.
* \param[in] key_buffer_size Size of the \p key_buffer buffer in bytes. This
* size is greater or equal to \p data_length.
* \param[out] key_buffer_length The length of the data written in \p
* key_buffer in bytes.
* \param[out] bits The key size in number of bits.
*
* \retval #PSA_SUCCESS The key was imported successfully.
* \retval #PSA_ERROR_INVALID_ARGUMENT
* The key data is not correctly formatted.
* \retval #PSA_ERROR_NOT_SUPPORTED
* \retval #PSA_ERROR_INSUFFICIENT_MEMORY
* \retval #PSA_ERROR_CORRUPTION_DETECTED
*/
psa_status_t psa_import_key_into_slot(
const psa_key_attributes_t *attributes,
const uint8_t *data, size_t data_length,
uint8_t *key_buffer, size_t key_buffer_size,
size_t *key_buffer_length, size_t *bits);
/** Export a key in binary format
*
* \note The signature of this function is that of a PSA driver export_key
* entry point. This function behaves as an export_key entry point as
* defined in the PSA driver interface specification.
*
* \param[in] attributes The attributes for the key to export.
* \param[in] key_buffer Material or context of the key to export.
* \param[in] key_buffer_size Size of the \p key_buffer buffer in bytes.
* \param[out] data Buffer where the key data is to be written.
* \param[in] data_size Size of the \p data buffer in bytes.
* \param[out] data_length On success, the number of bytes written in
* \p data
*
* \retval #PSA_SUCCESS The key was exported successfully.
* \retval #PSA_ERROR_NOT_SUPPORTED
* \retval #PSA_ERROR_COMMUNICATION_FAILURE
* \retval #PSA_ERROR_HARDWARE_FAILURE
* \retval #PSA_ERROR_CORRUPTION_DETECTED
* \retval #PSA_ERROR_STORAGE_FAILURE
* \retval #PSA_ERROR_INSUFFICIENT_MEMORY
*/
psa_status_t psa_export_key_internal(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
uint8_t *data, size_t data_size, size_t *data_length);
/** Export a public key or the public part of a key pair in binary format.
*
* \note The signature of this function is that of a PSA driver
* export_public_key entry point. This function behaves as an
* export_public_key entry point as defined in the PSA driver interface
* specification.
*
* \param[in] attributes The attributes for the key to export.
* \param[in] key_buffer Material or context of the key to export.
* \param[in] key_buffer_size Size of the \p key_buffer buffer in bytes.
* \param[out] data Buffer where the key data is to be written.
* \param[in] data_size Size of the \p data buffer in bytes.
* \param[out] data_length On success, the number of bytes written in
* \p data
*
* \retval #PSA_SUCCESS The public key was exported successfully.
* \retval #PSA_ERROR_NOT_SUPPORTED
* \retval #PSA_ERROR_COMMUNICATION_FAILURE
* \retval #PSA_ERROR_HARDWARE_FAILURE
* \retval #PSA_ERROR_CORRUPTION_DETECTED
* \retval #PSA_ERROR_STORAGE_FAILURE
* \retval #PSA_ERROR_INSUFFICIENT_MEMORY
*/
psa_status_t psa_export_public_key_internal(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
uint8_t *data, size_t data_size, size_t *data_length);
/**
* \brief Generate a key.
*
* \note The signature of the function is that of a PSA driver generate_key
* entry point.
*
* \param[in] attributes The attributes for the key to generate.
* \param[out] key_buffer Buffer where the key data is to be written.
* \param[in] key_buffer_size Size of \p key_buffer in bytes.
* \param[out] key_buffer_length On success, the number of bytes written in
* \p key_buffer.
*
* \retval #PSA_SUCCESS
* The key was generated successfully.
* \retval #PSA_ERROR_INVALID_ARGUMENT
* \retval #PSA_ERROR_NOT_SUPPORTED
* Key size in bits or type not supported.
* \retval #PSA_ERROR_BUFFER_TOO_SMALL
* The size of \p key_buffer is too small.
*/
psa_status_t psa_generate_key_internal(const psa_key_attributes_t *attributes,
uint8_t *key_buffer,
size_t key_buffer_size,
size_t *key_buffer_length);
/** Sign an already-calculated hash with a private key.
*
* \note The signature of this function is that of a PSA driver
* sign_hash entry point. This function behaves as a sign_hash
* entry point as defined in the PSA driver interface specification for
* transparent drivers.
*
* \param[in] attributes The attributes of the key to use for the
* operation.
* \param[in] key_buffer The buffer containing the key context.
* format.
* \param[in] key_buffer_size Size of the \p key_buffer buffer in bytes.
* \param[in] alg A signature algorithm that is compatible with
* the type of the key.
* \param[in] hash The hash or message to sign.
* \param[in] hash_length Size of the \p hash buffer in bytes.
* \param[out] signature Buffer where the signature is to be written.
* \param[in] signature_size Size of the \p signature buffer in bytes.
* \param[out] signature_length On success, the number of bytes
* that make up the returned signature value.
*
* \retval #PSA_SUCCESS
* \retval #PSA_ERROR_BUFFER_TOO_SMALL
* The size of the \p signature buffer is too small. You can
* determine a sufficient buffer size by calling
* #PSA_SIGN_OUTPUT_SIZE(\c key_type, \c key_bits, \p alg)
* where \c key_type and \c key_bits are the type and bit-size
* respectively of the key.
* \retval #PSA_ERROR_NOT_SUPPORTED
* \retval #PSA_ERROR_INVALID_ARGUMENT
* \retval #PSA_ERROR_INSUFFICIENT_MEMORY
* \retval #PSA_ERROR_CORRUPTION_DETECTED
* \retval #PSA_ERROR_INSUFFICIENT_ENTROPY
*/
psa_status_t psa_sign_hash_internal(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg, const uint8_t *hash, size_t hash_length,
uint8_t *signature, size_t signature_size, size_t *signature_length);
/**
* \brief Verify the signature a hash or short message using a public key.
*
* \note The signature of this function is that of a PSA driver
* verify_hash entry point. This function behaves as a verify_hash
* entry point as defined in the PSA driver interface specification for
* transparent drivers.
*
* \param[in] attributes The attributes of the key to use for the
* operation.
* \param[in] key_buffer The buffer containing the key context.
* format.
* \param[in] key_buffer_size Size of the \p key_buffer buffer in bytes.
* \param[in] alg A signature algorithm that is compatible with
* the type of the key.
* \param[in] hash The hash or message whose signature is to be
* verified.
* \param[in] hash_length Size of the \p hash buffer in bytes.
* \param[in] signature Buffer containing the signature to verify.
* \param[in] signature_length Size of the \p signature buffer in bytes.
*
* \retval #PSA_SUCCESS
* The signature is valid.
* \retval #PSA_ERROR_INVALID_SIGNATURE
* The calculation was performed successfully, but the passed
* signature is not a valid signature.
* \retval #PSA_ERROR_NOT_SUPPORTED
* \retval #PSA_ERROR_INVALID_ARGUMENT
* \retval #PSA_ERROR_INSUFFICIENT_MEMORY
*/
psa_status_t psa_verify_hash_internal(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg, const uint8_t *hash, size_t hash_length,
const uint8_t *signature, size_t signature_length);
#endif /* PSA_CRYPTO_CORE_H */