diff options
Diffstat (limited to 'library/psa_crypto_core.h')
| -rw-r--r-- | library/psa_crypto_core.h | 610 |
1 files changed, 610 insertions, 0 deletions
diff --git a/library/psa_crypto_core.h b/library/psa_crypto_core.h new file mode 100644 index 000000000..614cad1f4 --- /dev/null +++ b/library/psa_crypto_core.h @@ -0,0 +1,610 @@ +/* + * 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 + +#include "mbedtls/build_info.h" + +#include "psa/crypto.h" +#include "psa/crypto_se_driver.h" + +/** Constant-time buffer comparison + * + * \param[in] a Left-hand buffer for comparison. + * \param[in] b Right-hand buffer for comparison. + * \param n Amount of bytes to compare. + * + * \return 0 if the buffer contents are equal, non-zero otherwise + */ +static inline int mbedtls_psa_safer_memcmp( + const uint8_t *a, const uint8_t *b, size_t n ) +{ + size_t i; + unsigned char diff = 0; + + for( i = 0; i < n; i++ ) + diff |= a[i] ^ b[i]; + + return( diff ); +} + +/** 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 + +/** Get the description of a key given its identifier and policy constraints + * and lock it. + * + * The key must have allow all the usage flags set in \p usage. If \p alg is + * nonzero, the key must allow operations with this algorithm. If \p alg is + * zero, the algorithm is not checked. + * + * In case of a persistent key, the function loads the description of the key + * into a key slot if not already done. + * + * On success, the returned key slot is locked. It is the responsibility of + * the caller to unlock the key slot when it does not access it anymore. + */ +psa_status_t psa_get_and_lock_key_slot_with_policy( mbedtls_svc_key_id_t key, + psa_key_slot_t **p_slot, + psa_key_usage_t usage, + psa_algorithm_t alg ); + +/** 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 ); + +/** Try to allocate a buffer to an empty key slot. + * + * \param[in,out] slot Key slot to attach buffer to. + * \param[in] buffer_length Requested size of the buffer. + * + * \retval #PSA_SUCCESS + * The buffer has been successfully allocated. + * \retval #PSA_ERROR_INSUFFICIENT_MEMORY + * Not enough memory was available for allocation. + * \retval #PSA_ERROR_ALREADY_EXISTS + * Trying to allocate a buffer to a non-empty key slot. + */ +psa_status_t psa_allocate_buffer_to_slot( psa_key_slot_t *slot, + size_t buffer_length ); + +/** Wipe key data from a slot. Preserves metadata such as the policy. */ +psa_status_t psa_remove_key_data_from_memory( 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 ); + +/** 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 a message with a private key. For hash-and-sign algorithms, + * this includes the hashing step. + * + * \note The signature of this function is that of a PSA driver + * sign_message entry point. This function behaves as a sign_message + * entry point as defined in the PSA driver interface specification for + * transparent drivers. + * + * \note This function will call the driver for psa_sign_hash + * and go through driver dispatch again. + * + * \param[in] attributes The attributes of the key to use for the + * operation. + * \param[in] key_buffer The buffer containing the key context. + * \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] input The input message to sign. + * \param[in] input_length Size of the \p input 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_message_builtin( + const psa_key_attributes_t *attributes, + const uint8_t *key_buffer, size_t key_buffer_size, + psa_algorithm_t alg, const uint8_t *input, size_t input_length, + uint8_t *signature, size_t signature_size, size_t *signature_length ); + +/** Verify the signature of a message with a public key, using + * a hash-and-sign verification algorithm. + * + * \note The signature of this function is that of a PSA driver + * verify_message entry point. This function behaves as a verify_message + * entry point as defined in the PSA driver interface specification for + * transparent drivers. + * + * \note This function will call the driver for psa_verify_hash + * and go through driver dispatch again. + * + * \param[in] attributes The attributes of the key to use for the + * operation. + * \param[in] key_buffer The buffer containing the key context. + * \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] input The message whose signature is to be verified. + * \param[in] input_length Size of the \p input 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_message_builtin( + const psa_key_attributes_t *attributes, + const uint8_t *key_buffer, size_t key_buffer_size, + psa_algorithm_t alg, const uint8_t *input, size_t input_length, + const uint8_t *signature, size_t signature_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. + * \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_builtin( + 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. + * \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_builtin( + 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 ); + +/** + * \brief Validate the key bit size for unstructured keys. + * + * \note Check that the bit size is acceptable for a given key type for + * unstructured keys. + * + * \param[in] type The key type + * \param[in] bits The number of bits of the key + * + * \retval #PSA_SUCCESS + * The key type and size are valid. + * \retval #PSA_ERROR_INVALID_ARGUMENT + * The size in bits of the key is not valid. + * \retval #PSA_ERROR_NOT_SUPPORTED + * The type and/or the size in bits of the key or the combination of + * the two is not supported. + */ +psa_status_t psa_validate_unstructured_key_bit_size( psa_key_type_t type, + size_t bits ); + +/** Perform a key agreement and return the raw shared secret, using + built-in raw key agreement functions. + * + * \note The signature of this function is that of a PSA driver + * key_agreement entry point. This function behaves as a key_agreement + * 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 private key + * context. + * \param[in] key_buffer_size Size of the \p key_buffer buffer in + * bytes. + * \param[in] alg A key agreement algorithm that is + * compatible with the type of the key. + * \param[in] peer_key The buffer containing the key context + * of the peer's public key. + * \param[in] peer_key_length Size of the \p peer_key buffer in + * bytes. + * \param[out] shared_secret The buffer to which the shared secret + * is to be written. + * \param[in] shared_secret_size Size of the \p shared_secret buffer in + * bytes. + * \param[out] shared_secret_length On success, the number of bytes that make + * up the returned shared secret. + * \retval #PSA_SUCCESS + * Success. Shared secret successfully calculated. + * \retval #PSA_ERROR_INVALID_HANDLE + * \retval #PSA_ERROR_NOT_PERMITTED + * \retval #PSA_ERROR_INVALID_ARGUMENT + * \p alg is not a key agreement algorithm, or + * \p private_key is not compatible with \p alg, + * or \p peer_key is not valid for \p alg or not compatible with + * \p private_key. + * \retval #PSA_ERROR_BUFFER_TOO_SMALL + * \p shared_secret_size is too small + * \retval #PSA_ERROR_NOT_SUPPORTED + * \p alg is not a supported key agreement algorithm. + * \retval #PSA_ERROR_INSUFFICIENT_MEMORY + * \retval #PSA_ERROR_COMMUNICATION_FAILURE + * \retval #PSA_ERROR_HARDWARE_FAILURE + * \retval #PSA_ERROR_CORRUPTION_DETECTED + * \retval #PSA_ERROR_STORAGE_FAILURE + * \retval #PSA_ERROR_BAD_STATE + */ +psa_status_t psa_key_agreement_raw_builtin( + const psa_key_attributes_t *attributes, + const uint8_t *key_buffer, + size_t key_buffer_size, + psa_algorithm_t alg, + const uint8_t *peer_key, + size_t peer_key_length, + uint8_t *shared_secret, + size_t shared_secret_size, + size_t *shared_secret_length ); + +#endif /* PSA_CRYPTO_CORE_H */ |