mbedtls/library/psa_crypto_slot_management.h
Gilles Peskine 41e50d26ea Remove "allocated" flag from key slots
The flag to mark key slots as allocated was introduced to mark slots
that are claimed and in use, but do not have key material yet, at a
time when creating a key used several API functions: allocate a slot,
then progressively set its metadata, and finally create the key
material. Now that all of these steps are combined into a single
API function call, the notion of allocated-but-not-filled slot is no
longer relevant. So remove the corresponding flag.

A slot is occupied iff there is a key in it. (For a key in a secure
element, the key material is not present, but the slot contains the
key metadata.) This key must have a type which is nonzero, so use this
as an indicator that a slot is in use.
2019-07-31 16:54:38 +02:00

130 lines
4.5 KiB
C

/*
* PSA crypto layer on top of Mbed TLS crypto
*/
/* 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_SLOT_MANAGEMENT_H
#define PSA_CRYPTO_SLOT_MANAGEMENT_H
#include "psa/crypto.h"
#include "psa_crypto_se.h"
/* Number of key slots (plus one because 0 is not used).
* The value is a compile-time constant for now, for simplicity. */
#define PSA_KEY_SLOT_COUNT 32
/** Access a key slot at the given handle.
*
* \param handle Key handle to query.
* \param[out] p_slot On success, `*p_slot` contains a pointer to the
* key slot in memory designated by \p handle.
*
* \retval PSA_SUCCESS
* Success: \p handle is a handle to `*p_slot`. Note that `*p_slot`
* may be empty or occupied.
* \retval PSA_ERROR_INVALID_HANDLE
* \p handle is out of range or is not in use.
* \retval PSA_ERROR_BAD_STATE
* The library has not been initialized.
*/
psa_status_t psa_get_key_slot( psa_key_handle_t handle,
psa_key_slot_t **p_slot );
/** Initialize the key slot structures.
*
* \retval PSA_SUCCESS
* Currently this function always succeeds.
*/
psa_status_t psa_initialize_key_slots( void );
/** Delete all data from key slots in memory.
*
* This does not affect persistent storage. */
void psa_wipe_all_key_slots( void );
/** Find a free key slot.
*
* This function returns a key slot that is available for use and is in its
* ground state (all-bits-zero).
*
* \param[out] handle On success, a slot number that can be used as a
* handle to the slot.
* \param[out] p_slot On success, a pointer to the slot.
*
* \retval #PSA_SUCCESS
* \retval #PSA_ERROR_INSUFFICIENT_MEMORY
* \retval #PSA_ERROR_BAD_STATE
*/
psa_status_t psa_internal_allocate_key_slot( psa_key_handle_t *handle,
psa_key_slot_t **p_slot );
/** Test whether a lifetime designates a key in an external cryptoprocessor.
*
* \param lifetime The lifetime to test.
*
* \retval 1
* The lifetime designates an external key. There should be a
* registered driver for this lifetime, otherwise the key cannot
* be created or manipulated.
* \retval 0
* The lifetime designates a key that is volatile or in internal
* storage.
*/
static inline int psa_key_lifetime_is_external( psa_key_lifetime_t lifetime )
{
return( lifetime != PSA_KEY_LIFETIME_VOLATILE &&
lifetime != PSA_KEY_LIFETIME_PERSISTENT );
}
/** Test whether the given parameters are acceptable for a persistent key.
*
* This function does not access the storage in any way. It only tests
* whether the parameters are meaningful and permitted by general policy.
* It does not test whether the a file by the given id exists or could be
* created.
*
* If the key is in external storage, this function returns the corresponding
* driver.
*
* \param lifetime The lifetime to test.
* \param id The key id to test.
* \param[out] p_drv On output, if \p lifetime designates a key
* in an external processor, \c *p_drv is a pointer
* to the driver table entry fot this lifetime.
* If \p lifetime designates a transparent key,
* \c *p_drv is \c NULL.
* \param creating 0 if attempting to open an existing key.
* Nonzero if attempting to create a key.
*
* \retval PSA_SUCCESS
* The given parameters are valid.
* \retval PSA_ERROR_INVALID_ARGUMENT
* \p lifetime is volatile or is invalid.
* \retval PSA_ERROR_INVALID_ARGUMENT
* \p id is invalid.
*/
psa_status_t psa_validate_persistent_key_parameters(
psa_key_lifetime_t lifetime,
psa_key_file_id_t id,
psa_se_drv_table_entry_t **p_drv,
int creating );
#endif /* PSA_CRYPTO_SLOT_MANAGEMENT_H */