Add export_public_key entry point to p256-m driver

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
This commit is contained in:
Manuel Pégourié-Gonnard 2023-08-07 11:18:05 +02:00
parent 5424cf2e40
commit 18d7142efd
2 changed files with 61 additions and 0 deletions

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@ -104,6 +104,40 @@ psa_status_t p256_transparent_import_key(const psa_key_attributes_t *attributes,
return PSA_SUCCESS;
}
psa_status_t p256_transparent_export_public_key(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)
{
/* Is this the right curve? */
size_t bits = psa_get_key_bits(attributes);
psa_key_type_t type = psa_get_key_type(attributes);
if (bits != 256 || type != PSA_KEY_TYPE_ECC_KEY_PAIR(PSA_ECC_FAMILY_SECP_R1)) {
return PSA_ERROR_NOT_SUPPORTED;
}
/* Validate input and output sizes */
if (key_buffer_size != 32) {
return PSA_ERROR_INVALID_ARGUMENT;
}
if (data_size < 65) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
/* Output public key in the PSA export format */
data[0] = 0x04;
int ret = p256_public_from_private(data + 1, key_buffer);
if (ret != P256_SUCCESS) {
/* The only possible error is the private key was invalid */
return PSA_ERROR_INVALID_ARGUMENT;
}
*data_length = 65;
return PSA_SUCCESS;
}
psa_status_t p256_transparent_generate_key(
const psa_key_attributes_t *attributes,
uint8_t *key_buffer,

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@ -62,6 +62,33 @@ psa_status_t p256_transparent_import_key(const psa_key_attributes_t *attributes,
size_t *key_buffer_length,
size_t *bits);
/** Export SECP256R1 public key, from the private key.
*
* \param[in] attributes The attributes of the key to use for the
* operation.
* \param[in] key_buffer The private key in the export format.
* \param[in] key_buffer_size The size of the private key in bytes.
* \param[out] data The buffer to contain the public key in
* the export format upon successful return.
* \param[in] data_size The size of the \p data buffer in bytes.
* \param[out] data_length The length written to \p data in bytes.
*
* \retval #PSA_SUCCESS
* Success. Keypair generated and stored in buffer.
* \retval #PSA_ERROR_NOT_SUPPORTED
* The input is not supported by this driver (not SECP256R1).
* \retval #PSA_ERROR_INVALID_ARGUMENT
* The input is invalid.
* \retval #PSA_ERROR_BUFFER_TOO_SMALL
* \p key_buffer_size is too small.
*/
psa_status_t p256_transparent_export_public_key(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);
/** Generate SECP256R1 ECC Key Pair.
* Interface function which calls the p256-m key generation function and
* places it in the key buffer provided by the caller (mbed TLS) in the