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mbedtls/library/psa_crypto.c
Ryan Everett a103ec9ad4 Make one shot operations thread safe 
These all follow a pattern of locking some key slot,
reading its contents, and then unregistering from reading the slot.
psa_copy_key also writes to another slot,
but calls the functions needed to be threadsafe.

Signed-off-by: Ryan Everett <ryan.everett@arm.com>
2024-01-31 14:17:15 +00:00

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/*
* PSA crypto layer on top of Mbed TLS crypto
*/
/*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*/
#include "common.h"
#include "psa_crypto_core_common.h"
#if defined(MBEDTLS_PSA_CRYPTO_C)
#if defined(MBEDTLS_PSA_CRYPTO_CONFIG)
#include "check_crypto_config.h"
#endif
#include "psa/crypto.h"
#include "psa/crypto_values.h"
#include "psa_crypto_cipher.h"
#include "psa_crypto_core.h"
#include "psa_crypto_invasive.h"
#include "psa_crypto_driver_wrappers.h"
#include "psa_crypto_driver_wrappers_no_static.h"
#include "psa_crypto_ecp.h"
#include "psa_crypto_ffdh.h"
#include "psa_crypto_hash.h"
#include "psa_crypto_mac.h"
#include "psa_crypto_rsa.h"
#include "psa_crypto_ecp.h"
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
#include "psa_crypto_se.h"
#endif
#include "psa_crypto_slot_management.h"
/* Include internal declarations that are useful for implementing persistently
* stored keys. */
#include "psa_crypto_storage.h"
#include "psa_crypto_random_impl.h"
#include <stdlib.h>
#include <string.h>
#include "mbedtls/platform.h"
#include "mbedtls/aes.h"
#include "mbedtls/asn1.h"
#include "mbedtls/asn1write.h"
#include "mbedtls/bignum.h"
#include "mbedtls/camellia.h"
#include "mbedtls/chacha20.h"
#include "mbedtls/chachapoly.h"
#include "mbedtls/cipher.h"
#include "mbedtls/ccm.h"
#include "mbedtls/cmac.h"
#include "mbedtls/constant_time.h"
#include "mbedtls/des.h"
#include "mbedtls/ecdh.h"
#include "mbedtls/ecp.h"
#include "mbedtls/entropy.h"
#include "mbedtls/error.h"
#include "mbedtls/gcm.h"
#include "mbedtls/md5.h"
#include "mbedtls/pk.h"
#include "pk_wrap.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"
#include "mbedtls/ripemd160.h"
#include "mbedtls/rsa.h"
#include "mbedtls/sha1.h"
#include "mbedtls/sha256.h"
#include "mbedtls/sha512.h"
#include "mbedtls/psa_util.h"
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXPAND)
#define BUILTIN_ALG_ANY_HKDF 1
#endif
/****************************************************************/
/* Global data, support functions and library management */
/****************************************************************/
static int key_type_is_raw_bytes(psa_key_type_t type)
{
return PSA_KEY_TYPE_IS_UNSTRUCTURED(type);
}
/* Values for psa_global_data_t::rng_state */
#define RNG_NOT_INITIALIZED 0
#define RNG_INITIALIZED 1
#define RNG_SEEDED 2
typedef struct {
uint8_t initialized;
uint8_t rng_state;
uint8_t drivers_initialized;
mbedtls_psa_random_context_t rng;
} psa_global_data_t;
static psa_global_data_t global_data;
#if !defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
mbedtls_psa_drbg_context_t *const mbedtls_psa_random_state =
&global_data.rng.drbg;
#endif
#define GUARD_MODULE_INITIALIZED \
if (global_data.initialized == 0) \
return PSA_ERROR_BAD_STATE;
int psa_can_do_hash(psa_algorithm_t hash_alg)
{
(void) hash_alg;
return global_data.drivers_initialized;
}
int psa_can_do_cipher(psa_key_type_t key_type, psa_algorithm_t cipher_alg)
{
(void) key_type;
(void) cipher_alg;
return global_data.drivers_initialized;
}
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR_IMPORT) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_PUBLIC_KEY) || \
defined(PSA_WANT_KEY_TYPE_DH_KEY_PAIR_GENERATE)
static int psa_is_dh_key_size_valid(size_t bits)
{
if (bits != 2048 && bits != 3072 && bits != 4096 &&
bits != 6144 && bits != 8192) {
return 0;
}
return 1;
}
#endif /* MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR_IMPORT ||
MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_PUBLIC_KEY ||
PSA_WANT_KEY_TYPE_DH_KEY_PAIR_GENERATE */
psa_status_t mbedtls_to_psa_error(int ret)
{
/* Mbed TLS error codes can combine a high-level error code and a
* low-level error code. The low-level error usually reflects the
* root cause better, so dispatch on that preferably. */
int low_level_ret = -(-ret & 0x007f);
switch (low_level_ret != 0 ? low_level_ret : ret) {
case 0:
return PSA_SUCCESS;
#if defined(MBEDTLS_AES_C)
case MBEDTLS_ERR_AES_INVALID_KEY_LENGTH:
case MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH:
return PSA_ERROR_NOT_SUPPORTED;
case MBEDTLS_ERR_AES_BAD_INPUT_DATA:
return PSA_ERROR_INVALID_ARGUMENT;
#endif
#if defined(MBEDTLS_ASN1_PARSE_C) || defined(MBEDTLS_ASN1_WRITE_C)
case MBEDTLS_ERR_ASN1_OUT_OF_DATA:
case MBEDTLS_ERR_ASN1_UNEXPECTED_TAG:
case MBEDTLS_ERR_ASN1_INVALID_LENGTH:
case MBEDTLS_ERR_ASN1_LENGTH_MISMATCH:
case MBEDTLS_ERR_ASN1_INVALID_DATA:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_ASN1_ALLOC_FAILED:
return PSA_ERROR_INSUFFICIENT_MEMORY;
case MBEDTLS_ERR_ASN1_BUF_TOO_SMALL:
return PSA_ERROR_BUFFER_TOO_SMALL;
#endif
#if defined(MBEDTLS_CAMELLIA_C)
case MBEDTLS_ERR_CAMELLIA_BAD_INPUT_DATA:
case MBEDTLS_ERR_CAMELLIA_INVALID_INPUT_LENGTH:
return PSA_ERROR_NOT_SUPPORTED;
#endif
#if defined(MBEDTLS_CCM_C)
case MBEDTLS_ERR_CCM_BAD_INPUT:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_CCM_AUTH_FAILED:
return PSA_ERROR_INVALID_SIGNATURE;
#endif
#if defined(MBEDTLS_CHACHA20_C)
case MBEDTLS_ERR_CHACHA20_BAD_INPUT_DATA:
return PSA_ERROR_INVALID_ARGUMENT;
#endif
#if defined(MBEDTLS_CHACHAPOLY_C)
case MBEDTLS_ERR_CHACHAPOLY_BAD_STATE:
return PSA_ERROR_BAD_STATE;
case MBEDTLS_ERR_CHACHAPOLY_AUTH_FAILED:
return PSA_ERROR_INVALID_SIGNATURE;
#endif
#if defined(MBEDTLS_CIPHER_C)
case MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE:
return PSA_ERROR_NOT_SUPPORTED;
case MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_CIPHER_ALLOC_FAILED:
return PSA_ERROR_INSUFFICIENT_MEMORY;
case MBEDTLS_ERR_CIPHER_INVALID_PADDING:
return PSA_ERROR_INVALID_PADDING;
case MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_CIPHER_AUTH_FAILED:
return PSA_ERROR_INVALID_SIGNATURE;
case MBEDTLS_ERR_CIPHER_INVALID_CONTEXT:
return PSA_ERROR_CORRUPTION_DETECTED;
#endif
#if !(defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG) || \
defined(MBEDTLS_PSA_HMAC_DRBG_MD_TYPE))
/* Only check CTR_DRBG error codes if underlying mbedtls_xxx
* functions are passed a CTR_DRBG instance. */
case MBEDTLS_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED:
return PSA_ERROR_INSUFFICIENT_ENTROPY;
case MBEDTLS_ERR_CTR_DRBG_REQUEST_TOO_BIG:
case MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG:
return PSA_ERROR_NOT_SUPPORTED;
case MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR:
return PSA_ERROR_INSUFFICIENT_ENTROPY;
#endif
#if defined(MBEDTLS_DES_C)
case MBEDTLS_ERR_DES_INVALID_INPUT_LENGTH:
return PSA_ERROR_NOT_SUPPORTED;
#endif
case MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED:
case MBEDTLS_ERR_ENTROPY_NO_STRONG_SOURCE:
case MBEDTLS_ERR_ENTROPY_SOURCE_FAILED:
return PSA_ERROR_INSUFFICIENT_ENTROPY;
#if defined(MBEDTLS_GCM_C)
case MBEDTLS_ERR_GCM_AUTH_FAILED:
return PSA_ERROR_INVALID_SIGNATURE;
case MBEDTLS_ERR_GCM_BUFFER_TOO_SMALL:
return PSA_ERROR_BUFFER_TOO_SMALL;
case MBEDTLS_ERR_GCM_BAD_INPUT:
return PSA_ERROR_INVALID_ARGUMENT;
#endif
#if !defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG) && \
defined(MBEDTLS_PSA_HMAC_DRBG_MD_TYPE)
/* Only check HMAC_DRBG error codes if underlying mbedtls_xxx
* functions are passed a HMAC_DRBG instance. */
case MBEDTLS_ERR_HMAC_DRBG_ENTROPY_SOURCE_FAILED:
return PSA_ERROR_INSUFFICIENT_ENTROPY;
case MBEDTLS_ERR_HMAC_DRBG_REQUEST_TOO_BIG:
case MBEDTLS_ERR_HMAC_DRBG_INPUT_TOO_BIG:
return PSA_ERROR_NOT_SUPPORTED;
case MBEDTLS_ERR_HMAC_DRBG_FILE_IO_ERROR:
return PSA_ERROR_INSUFFICIENT_ENTROPY;
#endif
#if defined(MBEDTLS_MD_LIGHT)
case MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE:
return PSA_ERROR_NOT_SUPPORTED;
case MBEDTLS_ERR_MD_BAD_INPUT_DATA:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_MD_ALLOC_FAILED:
return PSA_ERROR_INSUFFICIENT_MEMORY;
#if defined(MBEDTLS_FS_IO)
case MBEDTLS_ERR_MD_FILE_IO_ERROR:
return PSA_ERROR_STORAGE_FAILURE;
#endif
#endif
#if defined(MBEDTLS_BIGNUM_C)
#if defined(MBEDTLS_FS_IO)
case MBEDTLS_ERR_MPI_FILE_IO_ERROR:
return PSA_ERROR_STORAGE_FAILURE;
#endif
case MBEDTLS_ERR_MPI_BAD_INPUT_DATA:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_MPI_INVALID_CHARACTER:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL:
return PSA_ERROR_BUFFER_TOO_SMALL;
case MBEDTLS_ERR_MPI_NEGATIVE_VALUE:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_MPI_DIVISION_BY_ZERO:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_MPI_NOT_ACCEPTABLE:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_MPI_ALLOC_FAILED:
return PSA_ERROR_INSUFFICIENT_MEMORY;
#endif
#if defined(MBEDTLS_PK_C)
case MBEDTLS_ERR_PK_ALLOC_FAILED:
return PSA_ERROR_INSUFFICIENT_MEMORY;
case MBEDTLS_ERR_PK_TYPE_MISMATCH:
case MBEDTLS_ERR_PK_BAD_INPUT_DATA:
return PSA_ERROR_INVALID_ARGUMENT;
#if defined(MBEDTLS_PSA_CRYPTO_STORAGE_C) || defined(MBEDTLS_FS_IO) || \
defined(MBEDTLS_PSA_ITS_FILE_C)
case MBEDTLS_ERR_PK_FILE_IO_ERROR:
return PSA_ERROR_STORAGE_FAILURE;
#endif
case MBEDTLS_ERR_PK_KEY_INVALID_VERSION:
case MBEDTLS_ERR_PK_KEY_INVALID_FORMAT:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_PK_UNKNOWN_PK_ALG:
return PSA_ERROR_NOT_SUPPORTED;
case MBEDTLS_ERR_PK_PASSWORD_REQUIRED:
case MBEDTLS_ERR_PK_PASSWORD_MISMATCH:
return PSA_ERROR_NOT_PERMITTED;
case MBEDTLS_ERR_PK_INVALID_PUBKEY:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_PK_INVALID_ALG:
case MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE:
case MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE:
return PSA_ERROR_NOT_SUPPORTED;
case MBEDTLS_ERR_PK_SIG_LEN_MISMATCH:
return PSA_ERROR_INVALID_SIGNATURE;
case MBEDTLS_ERR_PK_BUFFER_TOO_SMALL:
return PSA_ERROR_BUFFER_TOO_SMALL;
#endif
case MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED:
return PSA_ERROR_HARDWARE_FAILURE;
case MBEDTLS_ERR_PLATFORM_FEATURE_UNSUPPORTED:
return PSA_ERROR_NOT_SUPPORTED;
#if defined(MBEDTLS_RSA_C)
case MBEDTLS_ERR_RSA_BAD_INPUT_DATA:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_RSA_INVALID_PADDING:
return PSA_ERROR_INVALID_PADDING;
case MBEDTLS_ERR_RSA_KEY_GEN_FAILED:
return PSA_ERROR_HARDWARE_FAILURE;
case MBEDTLS_ERR_RSA_KEY_CHECK_FAILED:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_RSA_PUBLIC_FAILED:
case MBEDTLS_ERR_RSA_PRIVATE_FAILED:
return PSA_ERROR_CORRUPTION_DETECTED;
case MBEDTLS_ERR_RSA_VERIFY_FAILED:
return PSA_ERROR_INVALID_SIGNATURE;
case MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE:
return PSA_ERROR_BUFFER_TOO_SMALL;
case MBEDTLS_ERR_RSA_RNG_FAILED:
return PSA_ERROR_INSUFFICIENT_ENTROPY;
#endif
#if defined(MBEDTLS_ECP_LIGHT)
case MBEDTLS_ERR_ECP_BAD_INPUT_DATA:
case MBEDTLS_ERR_ECP_INVALID_KEY:
return PSA_ERROR_INVALID_ARGUMENT;
case MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL:
return PSA_ERROR_BUFFER_TOO_SMALL;
case MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE:
return PSA_ERROR_NOT_SUPPORTED;
case MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH:
case MBEDTLS_ERR_ECP_VERIFY_FAILED:
return PSA_ERROR_INVALID_SIGNATURE;
case MBEDTLS_ERR_ECP_ALLOC_FAILED:
return PSA_ERROR_INSUFFICIENT_MEMORY;
case MBEDTLS_ERR_ECP_RANDOM_FAILED:
return PSA_ERROR_INSUFFICIENT_ENTROPY;
#if defined(MBEDTLS_ECP_RESTARTABLE)
case MBEDTLS_ERR_ECP_IN_PROGRESS:
return PSA_OPERATION_INCOMPLETE;
#endif
#endif
case MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED:
return PSA_ERROR_CORRUPTION_DETECTED;
default:
return PSA_ERROR_GENERIC_ERROR;
}
}
/**
* \brief For output buffers which contain "tags"
* (outputs that may be checked for validity like
* hashes, MACs and signatures), fill the unused
* part of the output buffer (the whole buffer on
* error, the trailing part on success) with
* something that isn't a valid tag (barring an
* attack on the tag and deliberately-crafted
* input), in case the caller doesn't check the
* return status properly.
*
* \param output_buffer Pointer to buffer to wipe. May not be NULL
* unless \p output_buffer_size is zero.
* \param status Status of function called to generate
* output_buffer originally
* \param output_buffer_size Size of output buffer. If zero, \p output_buffer
* could be NULL.
* \param output_buffer_length Length of data written to output_buffer, must be
* less than \p output_buffer_size
*/
static void psa_wipe_tag_output_buffer(uint8_t *output_buffer, psa_status_t status,
size_t output_buffer_size, size_t output_buffer_length)
{
size_t offset = 0;
if (output_buffer_size == 0) {
/* If output_buffer_size is 0 then we have nothing to do. We must not
call memset because output_buffer may be NULL in this case */
return;
}
if (status == PSA_SUCCESS) {
offset = output_buffer_length;
}
memset(output_buffer + offset, '!', output_buffer_size - offset);
}
psa_status_t psa_validate_unstructured_key_bit_size(psa_key_type_t type,
size_t bits)
{
/* Check that the bit size is acceptable for the key type */
switch (type) {
case PSA_KEY_TYPE_RAW_DATA:
case PSA_KEY_TYPE_HMAC:
case PSA_KEY_TYPE_DERIVE:
case PSA_KEY_TYPE_PASSWORD:
case PSA_KEY_TYPE_PASSWORD_HASH:
break;
#if defined(PSA_WANT_KEY_TYPE_AES)
case PSA_KEY_TYPE_AES:
if (bits != 128 && bits != 192 && bits != 256) {
return PSA_ERROR_INVALID_ARGUMENT;
}
break;
#endif
#if defined(PSA_WANT_KEY_TYPE_ARIA)
case PSA_KEY_TYPE_ARIA:
if (bits != 128 && bits != 192 && bits != 256) {
return PSA_ERROR_INVALID_ARGUMENT;
}
break;
#endif
#if defined(PSA_WANT_KEY_TYPE_CAMELLIA)
case PSA_KEY_TYPE_CAMELLIA:
if (bits != 128 && bits != 192 && bits != 256) {
return PSA_ERROR_INVALID_ARGUMENT;
}
break;
#endif
#if defined(PSA_WANT_KEY_TYPE_DES)
case PSA_KEY_TYPE_DES:
if (bits != 64 && bits != 128 && bits != 192) {
return PSA_ERROR_INVALID_ARGUMENT;
}
break;
#endif
#if defined(PSA_WANT_KEY_TYPE_CHACHA20)
case PSA_KEY_TYPE_CHACHA20:
if (bits != 256) {
return PSA_ERROR_INVALID_ARGUMENT;
}
break;
#endif
default:
return PSA_ERROR_NOT_SUPPORTED;
}
if (bits % 8 != 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
return PSA_SUCCESS;
}
/** Check whether a given key type is valid for use with a given MAC algorithm
*
* Upon successful return of this function, the behavior of #PSA_MAC_LENGTH
* when called with the validated \p algorithm and \p key_type is well-defined.
*
* \param[in] algorithm The specific MAC algorithm (can be wildcard).
* \param[in] key_type The key type of the key to be used with the
* \p algorithm.
*
* \retval #PSA_SUCCESS
* The \p key_type is valid for use with the \p algorithm
* \retval #PSA_ERROR_INVALID_ARGUMENT
* The \p key_type is not valid for use with the \p algorithm
*/
MBEDTLS_STATIC_TESTABLE psa_status_t psa_mac_key_can_do(
psa_algorithm_t algorithm,
psa_key_type_t key_type)
{
if (PSA_ALG_IS_HMAC(algorithm)) {
if (key_type == PSA_KEY_TYPE_HMAC) {
return PSA_SUCCESS;
}
}
if (PSA_ALG_IS_BLOCK_CIPHER_MAC(algorithm)) {
/* Check that we're calling PSA_BLOCK_CIPHER_BLOCK_LENGTH with a cipher
* key. */
if ((key_type & PSA_KEY_TYPE_CATEGORY_MASK) ==
PSA_KEY_TYPE_CATEGORY_SYMMETRIC) {
/* PSA_BLOCK_CIPHER_BLOCK_LENGTH returns 1 for stream ciphers and
* the block length (larger than 1) for block ciphers. */
if (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) > 1) {
return PSA_SUCCESS;
}
}
}
return PSA_ERROR_INVALID_ARGUMENT;
}
psa_status_t psa_allocate_buffer_to_slot(psa_key_slot_t *slot,
size_t buffer_length)
{
if (slot->key.data != NULL) {
return PSA_ERROR_ALREADY_EXISTS;
}
slot->key.data = mbedtls_calloc(1, buffer_length);
if (slot->key.data == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
slot->key.bytes = buffer_length;
return PSA_SUCCESS;
}
psa_status_t psa_copy_key_material_into_slot(psa_key_slot_t *slot,
const uint8_t *data,
size_t data_length)
{
psa_status_t status = psa_allocate_buffer_to_slot(slot,
data_length);
if (status != PSA_SUCCESS) {
return status;
}
memcpy(slot->key.data, data, data_length);
return PSA_SUCCESS;
}
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)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_type_t type = attributes->core.type;
/* zero-length keys are never supported. */
if (data_length == 0) {
return PSA_ERROR_NOT_SUPPORTED;
}
if (key_type_is_raw_bytes(type)) {
*bits = PSA_BYTES_TO_BITS(data_length);
status = psa_validate_unstructured_key_bit_size(attributes->core.type,
*bits);
if (status != PSA_SUCCESS) {
return status;
}
/* Copy the key material. */
memcpy(key_buffer, data, data_length);
*key_buffer_length = data_length;
(void) key_buffer_size;
return PSA_SUCCESS;
} else if (PSA_KEY_TYPE_IS_ASYMMETRIC(type)) {
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR_IMPORT) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_PUBLIC_KEY)
if (PSA_KEY_TYPE_IS_DH(type)) {
if (psa_is_dh_key_size_valid(PSA_BYTES_TO_BITS(data_length)) == 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
return mbedtls_psa_ffdh_import_key(attributes,
data, data_length,
key_buffer, key_buffer_size,
key_buffer_length,
bits);
}
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR_IMPORT) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_PUBLIC_KEY) */
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_IMPORT) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_PUBLIC_KEY)
if (PSA_KEY_TYPE_IS_ECC(type)) {
return mbedtls_psa_ecp_import_key(attributes,
data, data_length,
key_buffer, key_buffer_size,
key_buffer_length,
bits);
}
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_IMPORT) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_PUBLIC_KEY) */
#if (defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) && \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT)) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY)
if (PSA_KEY_TYPE_IS_RSA(type)) {
return mbedtls_psa_rsa_import_key(attributes,
data, data_length,
key_buffer, key_buffer_size,
key_buffer_length,
bits);
}
#endif /* (defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) &&
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT)) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) */
}
return PSA_ERROR_NOT_SUPPORTED;
}
/** Calculate the intersection of two algorithm usage policies.
*
* Return 0 (which allows no operation) on incompatibility.
*/
static psa_algorithm_t psa_key_policy_algorithm_intersection(
psa_key_type_t key_type,
psa_algorithm_t alg1,
psa_algorithm_t alg2)
{
/* Common case: both sides actually specify the same policy. */
if (alg1 == alg2) {
return alg1;
}
/* If the policies are from the same hash-and-sign family, check
* if one is a wildcard. If so the other has the specific algorithm. */
if (PSA_ALG_IS_SIGN_HASH(alg1) &&
PSA_ALG_IS_SIGN_HASH(alg2) &&
(alg1 & ~PSA_ALG_HASH_MASK) == (alg2 & ~PSA_ALG_HASH_MASK)) {
if (PSA_ALG_SIGN_GET_HASH(alg1) == PSA_ALG_ANY_HASH) {
return alg2;
}
if (PSA_ALG_SIGN_GET_HASH(alg2) == PSA_ALG_ANY_HASH) {
return alg1;
}
}
/* If the policies are from the same AEAD family, check whether
* one of them is a minimum-tag-length wildcard. Calculate the most
* restrictive tag length. */
if (PSA_ALG_IS_AEAD(alg1) && PSA_ALG_IS_AEAD(alg2) &&
(PSA_ALG_AEAD_WITH_SHORTENED_TAG(alg1, 0) ==
PSA_ALG_AEAD_WITH_SHORTENED_TAG(alg2, 0))) {
size_t alg1_len = PSA_ALG_AEAD_GET_TAG_LENGTH(alg1);
size_t alg2_len = PSA_ALG_AEAD_GET_TAG_LENGTH(alg2);
size_t restricted_len = alg1_len > alg2_len ? alg1_len : alg2_len;
/* If both are wildcards, return most restrictive wildcard */
if (((alg1 & PSA_ALG_AEAD_AT_LEAST_THIS_LENGTH_FLAG) != 0) &&
((alg2 & PSA_ALG_AEAD_AT_LEAST_THIS_LENGTH_FLAG) != 0)) {
return PSA_ALG_AEAD_WITH_AT_LEAST_THIS_LENGTH_TAG(
alg1, restricted_len);
}
/* If only one is a wildcard, return specific algorithm if compatible. */
if (((alg1 & PSA_ALG_AEAD_AT_LEAST_THIS_LENGTH_FLAG) != 0) &&
(alg1_len <= alg2_len)) {
return alg2;
}
if (((alg2 & PSA_ALG_AEAD_AT_LEAST_THIS_LENGTH_FLAG) != 0) &&
(alg2_len <= alg1_len)) {
return alg1;
}
}
/* If the policies are from the same MAC family, check whether one
* of them is a minimum-MAC-length policy. Calculate the most
* restrictive tag length. */
if (PSA_ALG_IS_MAC(alg1) && PSA_ALG_IS_MAC(alg2) &&
(PSA_ALG_FULL_LENGTH_MAC(alg1) ==
PSA_ALG_FULL_LENGTH_MAC(alg2))) {
/* Validate the combination of key type and algorithm. Since the base
* algorithm of alg1 and alg2 are the same, we only need this once. */
if (PSA_SUCCESS != psa_mac_key_can_do(alg1, key_type)) {
return 0;
}
/* Get the (exact or at-least) output lengths for both sides of the
* requested intersection. None of the currently supported algorithms
* have an output length dependent on the actual key size, so setting it
* to a bogus value of 0 is currently OK.
*
* Note that for at-least-this-length wildcard algorithms, the output
* length is set to the shortest allowed length, which allows us to
* calculate the most restrictive tag length for the intersection. */
size_t alg1_len = PSA_MAC_LENGTH(key_type, 0, alg1);
size_t alg2_len = PSA_MAC_LENGTH(key_type, 0, alg2);
size_t restricted_len = alg1_len > alg2_len ? alg1_len : alg2_len;
/* If both are wildcards, return most restrictive wildcard */
if (((alg1 & PSA_ALG_MAC_AT_LEAST_THIS_LENGTH_FLAG) != 0) &&
((alg2 & PSA_ALG_MAC_AT_LEAST_THIS_LENGTH_FLAG) != 0)) {
return PSA_ALG_AT_LEAST_THIS_LENGTH_MAC(alg1, restricted_len);
}
/* If only one is an at-least-this-length policy, the intersection would
* be the other (fixed-length) policy as long as said fixed length is
* equal to or larger than the shortest allowed length. */
if ((alg1 & PSA_ALG_MAC_AT_LEAST_THIS_LENGTH_FLAG) != 0) {
return (alg1_len <= alg2_len) ? alg2 : 0;
}
if ((alg2 & PSA_ALG_MAC_AT_LEAST_THIS_LENGTH_FLAG) != 0) {
return (alg2_len <= alg1_len) ? alg1 : 0;
}
/* If none of them are wildcards, check whether they define the same tag
* length. This is still possible here when one is default-length and
* the other specific-length. Ensure to always return the
* specific-length version for the intersection. */
if (alg1_len == alg2_len) {
return PSA_ALG_TRUNCATED_MAC(alg1, alg1_len);
}
}
/* If the policies are incompatible, allow nothing. */
return 0;
}
static int psa_key_algorithm_permits(psa_key_type_t key_type,
psa_algorithm_t policy_alg,
psa_algorithm_t requested_alg)
{
/* Common case: the policy only allows requested_alg. */
if (requested_alg == policy_alg) {
return 1;
}
/* If policy_alg is a hash-and-sign with a wildcard for the hash,
* and requested_alg is the same hash-and-sign family with any hash,
* then requested_alg is compliant with policy_alg. */
if (PSA_ALG_IS_SIGN_HASH(requested_alg) &&
PSA_ALG_SIGN_GET_HASH(policy_alg) == PSA_ALG_ANY_HASH) {
return (policy_alg & ~PSA_ALG_HASH_MASK) ==
(requested_alg & ~PSA_ALG_HASH_MASK);
}
/* If policy_alg is a wildcard AEAD algorithm of the same base as
* the requested algorithm, check the requested tag length to be
* equal-length or longer than the wildcard-specified length. */
if (PSA_ALG_IS_AEAD(policy_alg) &&
PSA_ALG_IS_AEAD(requested_alg) &&
(PSA_ALG_AEAD_WITH_SHORTENED_TAG(policy_alg, 0) ==
PSA_ALG_AEAD_WITH_SHORTENED_TAG(requested_alg, 0)) &&
((policy_alg & PSA_ALG_AEAD_AT_LEAST_THIS_LENGTH_FLAG) != 0)) {
return PSA_ALG_AEAD_GET_TAG_LENGTH(policy_alg) <=
PSA_ALG_AEAD_GET_TAG_LENGTH(requested_alg);
}
/* If policy_alg is a MAC algorithm of the same base as the requested
* algorithm, check whether their MAC lengths are compatible. */
if (PSA_ALG_IS_MAC(policy_alg) &&
PSA_ALG_IS_MAC(requested_alg) &&
(PSA_ALG_FULL_LENGTH_MAC(policy_alg) ==
PSA_ALG_FULL_LENGTH_MAC(requested_alg))) {
/* Validate the combination of key type and algorithm. Since the policy
* and requested algorithms are the same, we only need this once. */
if (PSA_SUCCESS != psa_mac_key_can_do(policy_alg, key_type)) {
return 0;
}
/* Get both the requested output length for the algorithm which is to be
* verified, and the default output length for the base algorithm.
* Note that none of the currently supported algorithms have an output
* length dependent on actual key size, so setting it to a bogus value
* of 0 is currently OK. */
size_t requested_output_length = PSA_MAC_LENGTH(
key_type, 0, requested_alg);
size_t default_output_length = PSA_MAC_LENGTH(
key_type, 0,
PSA_ALG_FULL_LENGTH_MAC(requested_alg));
/* If the policy is default-length, only allow an algorithm with
* a declared exact-length matching the default. */
if (PSA_MAC_TRUNCATED_LENGTH(policy_alg) == 0) {
return requested_output_length == default_output_length;
}
/* If the requested algorithm is default-length, allow it if the policy
* length exactly matches the default length. */
if (PSA_MAC_TRUNCATED_LENGTH(requested_alg) == 0 &&
PSA_MAC_TRUNCATED_LENGTH(policy_alg) == default_output_length) {
return 1;
}
/* If policy_alg is an at-least-this-length wildcard MAC algorithm,
* check for the requested MAC length to be equal to or longer than the
* minimum allowed length. */
if ((policy_alg & PSA_ALG_MAC_AT_LEAST_THIS_LENGTH_FLAG) != 0) {
return PSA_MAC_TRUNCATED_LENGTH(policy_alg) <=
requested_output_length;
}
}
/* If policy_alg is a generic key agreement operation, then using it for
* a key derivation with that key agreement should also be allowed. This
* behaviour is expected to be defined in a future specification version. */
if (PSA_ALG_IS_RAW_KEY_AGREEMENT(policy_alg) &&
PSA_ALG_IS_KEY_AGREEMENT(requested_alg)) {
return PSA_ALG_KEY_AGREEMENT_GET_BASE(requested_alg) ==
policy_alg;
}
/* If it isn't explicitly permitted, it's forbidden. */
return 0;
}
/** Test whether a policy permits an algorithm.
*
* The caller must test usage flags separately.
*
* \note This function requires providing the key type for which the policy is
* being validated, since some algorithm policy definitions (e.g. MAC)
* have different properties depending on what kind of cipher it is
* combined with.
*
* \retval PSA_SUCCESS When \p alg is a specific algorithm
* allowed by the \p policy.
* \retval PSA_ERROR_INVALID_ARGUMENT When \p alg is not a specific algorithm
* \retval PSA_ERROR_NOT_PERMITTED When \p alg is a specific algorithm, but
* the \p policy does not allow it.
*/
static psa_status_t psa_key_policy_permits(const psa_key_policy_t *policy,
psa_key_type_t key_type,
psa_algorithm_t alg)
{
/* '0' is not a valid algorithm */
if (alg == 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
/* A requested algorithm cannot be a wildcard. */
if (PSA_ALG_IS_WILDCARD(alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
if (psa_key_algorithm_permits(key_type, policy->alg, alg) ||
psa_key_algorithm_permits(key_type, policy->alg2, alg)) {
return PSA_SUCCESS;
} else {
return PSA_ERROR_NOT_PERMITTED;
}
}
/** Restrict a key policy based on a constraint.
*
* \note This function requires providing the key type for which the policy is
* being restricted, since some algorithm policy definitions (e.g. MAC)
* have different properties depending on what kind of cipher it is
* combined with.
*
* \param[in] key_type The key type for which to restrict the policy
* \param[in,out] policy The policy to restrict.
* \param[in] constraint The policy constraint to apply.
*
* \retval #PSA_SUCCESS
* \c *policy contains the intersection of the original value of
* \c *policy and \c *constraint.
* \retval #PSA_ERROR_INVALID_ARGUMENT
* \c key_type, \c *policy and \c *constraint are incompatible.
* \c *policy is unchanged.
*/
static psa_status_t psa_restrict_key_policy(
psa_key_type_t key_type,
psa_key_policy_t *policy,
const psa_key_policy_t *constraint)
{
psa_algorithm_t intersection_alg =
psa_key_policy_algorithm_intersection(key_type, policy->alg,
constraint->alg);
psa_algorithm_t intersection_alg2 =
psa_key_policy_algorithm_intersection(key_type, policy->alg2,
constraint->alg2);
if (intersection_alg == 0 && policy->alg != 0 && constraint->alg != 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
if (intersection_alg2 == 0 && policy->alg2 != 0 && constraint->alg2 != 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
policy->usage &= constraint->usage;
policy->alg = intersection_alg;
policy->alg2 = intersection_alg2;
return PSA_SUCCESS;
}
/** 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 has been registered for reading.
* It is the responsibility of the caller to call psa_unregister_read(slot)
* when they have finished reading the contents of the slot.
*/
static 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)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot = NULL;
status = psa_get_and_lock_key_slot(key, p_slot);
if (status != PSA_SUCCESS) {
return status;
}
slot = *p_slot;
/* Enforce that usage policy for the key slot contains all the flags
* required by the usage parameter. There is one exception: public
* keys can always be exported, so we treat public key objects as
* if they had the export flag. */
if (PSA_KEY_TYPE_IS_PUBLIC_KEY(slot->attr.type)) {
usage &= ~PSA_KEY_USAGE_EXPORT;
}
if ((slot->attr.policy.usage & usage) != usage) {
status = PSA_ERROR_NOT_PERMITTED;
goto error;
}
/* Enforce that the usage policy permits the requested algorithm. */
if (alg != 0) {
status = psa_key_policy_permits(&slot->attr.policy,
slot->attr.type,
alg);
if (status != PSA_SUCCESS) {
goto error;
}
}
return PSA_SUCCESS;
error:
*p_slot = NULL;
psa_unregister_read_under_mutex(slot);
return status;
}
/** Get a key slot containing a transparent key and lock it.
*
* A transparent key is a key for which the key material is directly
* available, as opposed to a key in a secure element and/or to be used
* by a secure element.
*
* This is a temporary function that may be used instead of
* psa_get_and_lock_key_slot_with_policy() when there is no opaque key support
* for a cryptographic operation.
*
* On success, the returned key slot has been registered for reading.
* It is the responsibility of the caller to call psa_unregister_read(slot)
* when they have finished reading the contents of the slot.
*/
static psa_status_t psa_get_and_lock_transparent_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)
{
psa_status_t status = psa_get_and_lock_key_slot_with_policy(key, p_slot,
usage, alg);
if (status != PSA_SUCCESS) {
return status;
}
if (psa_key_lifetime_is_external((*p_slot)->attr.lifetime)) {
psa_unregister_read_under_mutex(*p_slot);
*p_slot = NULL;
return PSA_ERROR_NOT_SUPPORTED;
}
return PSA_SUCCESS;
}
psa_status_t psa_remove_key_data_from_memory(psa_key_slot_t *slot)
{
if (slot->key.data != NULL) {
mbedtls_zeroize_and_free(slot->key.data, slot->key.bytes);
}
slot->key.data = NULL;
slot->key.bytes = 0;
return PSA_SUCCESS;
}
/** Completely wipe a slot in memory, including its policy.
* Persistent storage is not affected. */
psa_status_t psa_wipe_key_slot(psa_key_slot_t *slot)
{
psa_status_t status = psa_remove_key_data_from_memory(slot);
/*
* As the return error code may not be handled in case of multiple errors,
* do our best to report an unexpected amount of registered readers or
* an unexpected state.
* Assert with MBEDTLS_TEST_HOOK_TEST_ASSERT that the slot is valid for
* wiping.
* if the MBEDTLS_TEST_HOOKS configuration option is enabled and the
* function is called as part of the execution of a test suite, the
* execution of the test suite is stopped in error if the assertion fails.
*/
switch (slot->state) {
case PSA_SLOT_FULL:
/* In this state psa_wipe_key_slot() must only be called if the
* caller is the last reader. */
case PSA_SLOT_PENDING_DELETION:
/* In this state psa_wipe_key_slot() must only be called if the
* caller is the last reader. */
if (slot->registered_readers != 1) {
MBEDTLS_TEST_HOOK_TEST_ASSERT(slot->registered_readers == 1);
status = PSA_ERROR_CORRUPTION_DETECTED;
}
break;
case PSA_SLOT_FILLING:
/* In this state registered_readers must be 0. */
if (slot->registered_readers != 0) {
MBEDTLS_TEST_HOOK_TEST_ASSERT(slot->registered_readers == 0);
status = PSA_ERROR_CORRUPTION_DETECTED;
}
break;
case PSA_SLOT_EMPTY:
/* The slot is already empty, it cannot be wiped. */
MBEDTLS_TEST_HOOK_TEST_ASSERT(slot->state != PSA_SLOT_EMPTY);
status = PSA_ERROR_CORRUPTION_DETECTED;
break;
default:
/* The slot's state is invalid. */
status = PSA_ERROR_CORRUPTION_DETECTED;
}
/* Multipart operations may still be using the key. This is safe
* because all multipart operation objects are independent from
* the key slot: if they need to access the key after the setup
* phase, they have a copy of the key. Note that this means that
* key material can linger until all operations are completed. */
/* At this point, key material and other type-specific content has
* been wiped. Clear remaining metadata. We can call memset and not
* zeroize because the metadata is not particularly sensitive.
* This memset also sets the slot's state to PSA_SLOT_EMPTY. */
memset(slot, 0, sizeof(*slot));
return status;
}
psa_status_t psa_destroy_key(mbedtls_svc_key_id_t key)
{
psa_key_slot_t *slot;
psa_status_t status; /* status of the last operation */
psa_status_t overall_status = PSA_SUCCESS;
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
psa_se_drv_table_entry_t *driver;
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
if (mbedtls_svc_key_id_is_null(key)) {
return PSA_SUCCESS;
}
/*
* Get the description of the key in a key slot, and register to read it.
* In the case of a persistent key, this will load the key description
* from persistent memory if not done yet.
* We cannot avoid this loading as without it we don't know if
* the key is operated by an SE or not and this information is needed by
* the current implementation. */
status = psa_get_and_lock_key_slot(key, &slot);
if (status != PSA_SUCCESS) {
return status;
}
/* Set the key slot containing the key description's state to
* PENDING_DELETION. This stops new operations from registering
* to read the slot. Current readers can safely continue to access
* the key within the slot; the last registered reader will
* automatically wipe the slot when they call psa_unregister_read().
* If the key is persistent, we can now delete the copy of the key
* from memory. If the key is opaque, we require the driver to
* deal with the deletion. */
slot->state = PSA_SLOT_PENDING_DELETION;
if (PSA_KEY_LIFETIME_IS_READ_ONLY(slot->attr.lifetime)) {
/* Refuse the destruction of a read-only key (which may or may not work
* if we attempt it, depending on whether the key is merely read-only
* by policy or actually physically read-only).
* Just do the best we can, which is to wipe the copy in memory
* (done in this function's cleanup code). */
overall_status = PSA_ERROR_NOT_PERMITTED;
goto exit;
}
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
driver = psa_get_se_driver_entry(slot->attr.lifetime);
if (driver != NULL) {
/* For a key in a secure element, we need to do three things:
* remove the key file in internal storage, destroy the
* key inside the secure element, and update the driver's
* persistent data. Start a transaction that will encompass these
* three actions. */
psa_crypto_prepare_transaction(PSA_CRYPTO_TRANSACTION_DESTROY_KEY);
psa_crypto_transaction.key.lifetime = slot->attr.lifetime;
psa_crypto_transaction.key.slot = psa_key_slot_get_slot_number(slot);
psa_crypto_transaction.key.id = slot->attr.id;
status = psa_crypto_save_transaction();
if (status != PSA_SUCCESS) {
(void) psa_crypto_stop_transaction();
/* We should still try to destroy the key in the secure
* element and the key metadata in storage. This is especially
* important if the error is that the storage is full.
* But how to do it exactly without risking an inconsistent
* state after a reset?
* https://github.com/ARMmbed/mbed-crypto/issues/215
*/
overall_status = status;
goto exit;
}
status = psa_destroy_se_key(driver,
psa_key_slot_get_slot_number(slot));
if (overall_status == PSA_SUCCESS) {
overall_status = status;
}
}
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
#if defined(MBEDTLS_PSA_CRYPTO_STORAGE_C)
if (!PSA_KEY_LIFETIME_IS_VOLATILE(slot->attr.lifetime)) {
/* Destroy the copy of the persistent key from storage.
* The slot will still hold a copy of the key until the last reader
* unregisters. */
status = psa_destroy_persistent_key(slot->attr.id);
if (overall_status == PSA_SUCCESS) {
overall_status = status;
}
/* TODO: other slots may have a copy of the same key. We should
* invalidate them.
* https://github.com/ARMmbed/mbed-crypto/issues/214
*/
}
#endif /* defined(MBEDTLS_PSA_CRYPTO_STORAGE_C) */
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
if (driver != NULL) {
status = psa_save_se_persistent_data(driver);
if (overall_status == PSA_SUCCESS) {
overall_status = status;
}
status = psa_crypto_stop_transaction();
if (overall_status == PSA_SUCCESS) {
overall_status = status;
}
}
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
exit:
/* Unregister from reading the slot. If we are the last active reader
* then this will wipe the slot. */
status = psa_unregister_read(slot);
/* Prioritize CORRUPTION_DETECTED from unregistering over
* a storage error. */
if (status != PSA_SUCCESS) {
overall_status = status;
}
return overall_status;
}
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY)
static psa_status_t psa_get_rsa_public_exponent(
const mbedtls_rsa_context *rsa,
psa_key_attributes_t *attributes)
{
mbedtls_mpi mpi;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
uint8_t *buffer = NULL;
size_t buflen;
mbedtls_mpi_init(&mpi);
ret = mbedtls_rsa_export(rsa, NULL, NULL, NULL, NULL, &mpi);
if (ret != 0) {
goto exit;
}
if (mbedtls_mpi_cmp_int(&mpi, 65537) == 0) {
/* It's the default value, which is reported as an empty string,
* so there's nothing to do. */
goto exit;
}
buflen = mbedtls_mpi_size(&mpi);
buffer = mbedtls_calloc(1, buflen);
if (buffer == NULL) {
ret = MBEDTLS_ERR_MPI_ALLOC_FAILED;
goto exit;
}
ret = mbedtls_mpi_write_binary(&mpi, buffer, buflen);
if (ret != 0) {
goto exit;
}
attributes->domain_parameters = buffer;
attributes->domain_parameters_size = buflen;
exit:
mbedtls_mpi_free(&mpi);
if (ret != 0) {
mbedtls_free(buffer);
}
return mbedtls_to_psa_error(ret);
}
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) */
/** Retrieve all the publicly-accessible attributes of a key.
*/
psa_status_t psa_get_key_attributes(mbedtls_svc_key_id_t key,
psa_key_attributes_t *attributes)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
psa_reset_key_attributes(attributes);
status = psa_get_and_lock_key_slot_with_policy(key, &slot, 0, 0);
if (status != PSA_SUCCESS) {
return status;
}
attributes->core = slot->attr;
attributes->core.flags &= (MBEDTLS_PSA_KA_MASK_EXTERNAL_ONLY |
MBEDTLS_PSA_KA_MASK_DUAL_USE);
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
if (psa_get_se_driver_entry(slot->attr.lifetime) != NULL) {
psa_set_key_slot_number(attributes,
psa_key_slot_get_slot_number(slot));
}
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
switch (slot->attr.type) {
#if (defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) && \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT)) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY)
case PSA_KEY_TYPE_RSA_KEY_PAIR:
case PSA_KEY_TYPE_RSA_PUBLIC_KEY:
/* TODO: This is a temporary situation where domain parameters are deprecated,
* but we need it for namely generating an RSA key with a non-default exponent.
* This would be improved after https://github.com/Mbed-TLS/mbedtls/issues/6494.
*/
if (!psa_key_lifetime_is_external(slot->attr.lifetime)) {
mbedtls_rsa_context *rsa = NULL;
status = mbedtls_psa_rsa_load_representation(
slot->attr.type,
slot->key.data,
slot->key.bytes,
&rsa);
if (status != PSA_SUCCESS) {
break;
}
status = psa_get_rsa_public_exponent(rsa,
attributes);
mbedtls_rsa_free(rsa);
mbedtls_free(rsa);
}
break;
#else
case PSA_KEY_TYPE_RSA_KEY_PAIR:
case PSA_KEY_TYPE_RSA_PUBLIC_KEY:
attributes->domain_parameters = NULL;
attributes->domain_parameters_size = SIZE_MAX;
break;
#endif /* (defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) && \
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT)) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) */
default:
/* Nothing else to do. */
break;
}
if (status != PSA_SUCCESS) {
psa_reset_key_attributes(attributes);
}
unlock_status = psa_unregister_read_under_mutex(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
psa_status_t psa_get_key_slot_number(
const psa_key_attributes_t *attributes,
psa_key_slot_number_t *slot_number)
{
if (attributes->core.flags & MBEDTLS_PSA_KA_FLAG_HAS_SLOT_NUMBER) {
*slot_number = attributes->slot_number;
return PSA_SUCCESS;
} else {
return PSA_ERROR_INVALID_ARGUMENT;
}
}
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
static psa_status_t psa_export_key_buffer_internal(const uint8_t *key_buffer,
size_t key_buffer_size,
uint8_t *data,
size_t data_size,
size_t *data_length)
{
if (key_buffer_size > data_size) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
memcpy(data, key_buffer, key_buffer_size);
memset(data + key_buffer_size, 0,
data_size - key_buffer_size);
*data_length = key_buffer_size;
return PSA_SUCCESS;
}
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)
{
psa_key_type_t type = attributes->core.type;
if (key_type_is_raw_bytes(type) ||
PSA_KEY_TYPE_IS_RSA(type) ||
PSA_KEY_TYPE_IS_ECC(type) ||
PSA_KEY_TYPE_IS_DH(type)) {
return psa_export_key_buffer_internal(
key_buffer, key_buffer_size,
data, data_size, data_length);
} else {
/* This shouldn't happen in the reference implementation, but
it is valid for a special-purpose implementation to omit
support for exporting certain key types. */
return PSA_ERROR_NOT_SUPPORTED;
}
}
psa_status_t psa_export_key(mbedtls_svc_key_id_t key,
uint8_t *data,
size_t data_size,
size_t *data_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
/* Reject a zero-length output buffer now, since this can never be a
* valid key representation. This way we know that data must be a valid
* pointer and we can do things like memset(data, ..., data_size). */
if (data_size == 0) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
/* Set the key to empty now, so that even when there are errors, we always
* set data_length to a value between 0 and data_size. On error, setting
* the key to empty is a good choice because an empty key representation is
* unlikely to be accepted anywhere. */
*data_length = 0;
/* Export requires the EXPORT flag. There is an exception for public keys,
* which don't require any flag, but
* psa_get_and_lock_key_slot_with_policy() takes care of this.
*/
status = psa_get_and_lock_key_slot_with_policy(key, &slot,
PSA_KEY_USAGE_EXPORT, 0);
if (status != PSA_SUCCESS) {
return status;
}
psa_key_attributes_t attributes = {
.core = slot->attr
};
status = psa_driver_wrapper_export_key(&attributes,
slot->key.data, slot->key.bytes,
data, data_size, data_length);
unlock_status = psa_unregister_read_under_mutex(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
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)
{
psa_key_type_t type = attributes->core.type;
if (PSA_KEY_TYPE_IS_PUBLIC_KEY(type) &&
(PSA_KEY_TYPE_IS_RSA(type) || PSA_KEY_TYPE_IS_ECC(type) ||
PSA_KEY_TYPE_IS_DH(type))) {
/* Exporting public -> public */
return psa_export_key_buffer_internal(
key_buffer, key_buffer_size,
data, data_size, data_length);
} else if (PSA_KEY_TYPE_IS_RSA(type)) {
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY)
return mbedtls_psa_rsa_export_public_key(attributes,
key_buffer,
key_buffer_size,
data,
data_size,
data_length);
#else
/* We don't know how to convert a private RSA key to public. */
return PSA_ERROR_NOT_SUPPORTED;
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) */
} else if (PSA_KEY_TYPE_IS_ECC(type)) {
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_EXPORT) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_PUBLIC_KEY)
return mbedtls_psa_ecp_export_public_key(attributes,
key_buffer,
key_buffer_size,
data,
data_size,
data_length);
#else
/* We don't know how to convert a private ECC key to public */
return PSA_ERROR_NOT_SUPPORTED;
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_EXPORT) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_PUBLIC_KEY) */
} else if (PSA_KEY_TYPE_IS_DH(type)) {
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR_EXPORT) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_PUBLIC_KEY)
return mbedtls_psa_ffdh_export_public_key(attributes,
key_buffer,
key_buffer_size,
data, data_size,
data_length);
#else
return PSA_ERROR_NOT_SUPPORTED;
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR_EXPORT) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_PUBLIC_KEY) */
} else {
(void) key_buffer;
(void) key_buffer_size;
(void) data;
(void) data_size;
(void) data_length;
return PSA_ERROR_NOT_SUPPORTED;
}
}
psa_status_t psa_export_public_key(mbedtls_svc_key_id_t key,
uint8_t *data,
size_t data_size,
size_t *data_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
psa_key_attributes_t attributes;
/* Reject a zero-length output buffer now, since this can never be a
* valid key representation. This way we know that data must be a valid
* pointer and we can do things like memset(data, ..., data_size). */
if (data_size == 0) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
/* Set the key to empty now, so that even when there are errors, we always
* set data_length to a value between 0 and data_size. On error, setting
* the key to empty is a good choice because an empty key representation is
* unlikely to be accepted anywhere. */
*data_length = 0;
/* Exporting a public key doesn't require a usage flag. */
status = psa_get_and_lock_key_slot_with_policy(key, &slot, 0, 0);
if (status != PSA_SUCCESS) {
return status;
}
if (!PSA_KEY_TYPE_IS_ASYMMETRIC(slot->attr.type)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
status = psa_driver_wrapper_export_public_key(
&attributes, slot->key.data, slot->key.bytes,
data, data_size, data_length);
exit:
unlock_status = psa_unregister_read_under_mutex(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
MBEDTLS_STATIC_ASSERT(
(MBEDTLS_PSA_KA_MASK_EXTERNAL_ONLY & MBEDTLS_PSA_KA_MASK_DUAL_USE) == 0,
"One or more key attribute flag is listed as both external-only and dual-use")
MBEDTLS_STATIC_ASSERT(
(PSA_KA_MASK_INTERNAL_ONLY & MBEDTLS_PSA_KA_MASK_DUAL_USE) == 0,
"One or more key attribute flag is listed as both internal-only and dual-use")
MBEDTLS_STATIC_ASSERT(
(PSA_KA_MASK_INTERNAL_ONLY & MBEDTLS_PSA_KA_MASK_EXTERNAL_ONLY) == 0,
"One or more key attribute flag is listed as both internal-only and external-only")
/** Validate that a key policy is internally well-formed.
*
* This function only rejects invalid policies. It does not validate the
* consistency of the policy with respect to other attributes of the key
* such as the key type.
*/
static psa_status_t psa_validate_key_policy(const psa_key_policy_t *policy)
{
if ((policy->usage & ~(PSA_KEY_USAGE_EXPORT |
PSA_KEY_USAGE_COPY |
PSA_KEY_USAGE_ENCRYPT |
PSA_KEY_USAGE_DECRYPT |
PSA_KEY_USAGE_SIGN_MESSAGE |
PSA_KEY_USAGE_VERIFY_MESSAGE |
PSA_KEY_USAGE_SIGN_HASH |
PSA_KEY_USAGE_VERIFY_HASH |
PSA_KEY_USAGE_VERIFY_DERIVATION |
PSA_KEY_USAGE_DERIVE)) != 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
return PSA_SUCCESS;
}
/** Validate the internal consistency of key attributes.
*
* This function only rejects invalid attribute values. If does not
* validate the consistency of the attributes with any key data that may
* be involved in the creation of the key.
*
* Call this function early in the key creation process.
*
* \param[in] attributes Key attributes for the new key.
* \param[out] p_drv On any return, the driver for the key, if any.
* NULL for a transparent key.
*
*/
static psa_status_t psa_validate_key_attributes(
const psa_key_attributes_t *attributes,
psa_se_drv_table_entry_t **p_drv)
{
psa_status_t status = PSA_ERROR_INVALID_ARGUMENT;
psa_key_lifetime_t lifetime = psa_get_key_lifetime(attributes);
mbedtls_svc_key_id_t key = psa_get_key_id(attributes);
status = psa_validate_key_location(lifetime, p_drv);
if (status != PSA_SUCCESS) {
return status;
}
status = psa_validate_key_persistence(lifetime);
if (status != PSA_SUCCESS) {
return status;
}
if (PSA_KEY_LIFETIME_IS_VOLATILE(lifetime)) {
if (MBEDTLS_SVC_KEY_ID_GET_KEY_ID(key) != 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
} else {
if (!psa_is_valid_key_id(psa_get_key_id(attributes), 0)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
}
status = psa_validate_key_policy(&attributes->core.policy);
if (status != PSA_SUCCESS) {
return status;
}
/* Refuse to create overly large keys.
* Note that this doesn't trigger on import if the attributes don't
* explicitly specify a size (so psa_get_key_bits returns 0), so
* psa_import_key() needs its own checks. */
if (psa_get_key_bits(attributes) > PSA_MAX_KEY_BITS) {
return PSA_ERROR_NOT_SUPPORTED;
}
/* Reject invalid flags. These should not be reachable through the API. */
if (attributes->core.flags & ~(MBEDTLS_PSA_KA_MASK_EXTERNAL_ONLY |
MBEDTLS_PSA_KA_MASK_DUAL_USE)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
return PSA_SUCCESS;
}
/** Prepare a key slot to receive key material.
*
* This function allocates a key slot and sets its metadata.
*
* If this function fails, call psa_fail_key_creation().
*
* This function is intended to be used as follows:
* -# Call psa_start_key_creation() to allocate a key slot, prepare
* it with the specified attributes, and in case of a volatile key assign it
* a volatile key identifier.
* -# Populate the slot with the key material.
* -# Call psa_finish_key_creation() to finalize the creation of the slot.
* In case of failure at any step, stop the sequence and call
* psa_fail_key_creation().
*
* On success, the key slot's state is PSA_SLOT_FILLING.
* It is the responsibility of the caller to change the slot's state to
* PSA_SLOT_EMPTY/FULL once key creation has finished.
*
* \param method An identification of the calling function.
* \param[in] attributes Key attributes for the new key.
* \param[out] p_slot On success, a pointer to the prepared slot.
* \param[out] p_drv On any return, the driver for the key, if any.
* NULL for a transparent key.
*
* \retval #PSA_SUCCESS
* The key slot is ready to receive key material.
* \return If this function fails, the key slot is an invalid state.
* You must call psa_fail_key_creation() to wipe and free the slot.
*/
static psa_status_t psa_start_key_creation(
psa_key_creation_method_t method,
const psa_key_attributes_t *attributes,
psa_key_slot_t **p_slot,
psa_se_drv_table_entry_t **p_drv)
{
psa_status_t status;
psa_key_id_t volatile_key_id;
psa_key_slot_t *slot;
(void) method;
*p_drv = NULL;
status = psa_validate_key_attributes(attributes, p_drv);
if (status != PSA_SUCCESS) {
return status;
}
status = psa_reserve_free_key_slot(&volatile_key_id, p_slot);
if (status != PSA_SUCCESS) {
return status;
}
slot = *p_slot;
/* We're storing the declared bit-size of the key. It's up to each
* creation mechanism to verify that this information is correct.
* It's automatically correct for mechanisms that use the bit-size as
* an input (generate, device) but not for those where the bit-size
* is optional (import, copy). In case of a volatile key, assign it the
* volatile key identifier associated to the slot returned to contain its
* definition. */
slot->attr = attributes->core;
if (PSA_KEY_LIFETIME_IS_VOLATILE(slot->attr.lifetime)) {
#if !defined(MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER)
slot->attr.id = volatile_key_id;
#else
slot->attr.id.key_id = volatile_key_id;
#endif
}
/* Erase external-only flags from the internal copy. To access
* external-only flags, query `attributes`. Thanks to the check
* in psa_validate_key_attributes(), this leaves the dual-use
* flags and any internal flag that psa_reserve_free_key_slot()
* may have set. */
slot->attr.flags &= ~MBEDTLS_PSA_KA_MASK_EXTERNAL_ONLY;
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
/* For a key in a secure element, we need to do three things
* when creating or registering a persistent key:
* create the key file in internal storage, create the
* key inside the secure element, and update the driver's
* persistent data. This is done by starting a transaction that will
* encompass these three actions.
* For registering a volatile key, we just need to find an appropriate
* slot number inside the SE. Since the key is designated volatile, creating
* a transaction is not required. */
/* The first thing to do is to find a slot number for the new key.
* We save the slot number in persistent storage as part of the
* transaction data. It will be needed to recover if the power
* fails during the key creation process, to clean up on the secure
* element side after restarting. Obtaining a slot number from the
* secure element driver updates its persistent state, but we do not yet
* save the driver's persistent state, so that if the power fails,
* we can roll back to a state where the key doesn't exist. */
if (*p_drv != NULL) {
psa_key_slot_number_t slot_number;
status = psa_find_se_slot_for_key(attributes, method, *p_drv,
&slot_number);
if (status != PSA_SUCCESS) {
return status;
}
if (!PSA_KEY_LIFETIME_IS_VOLATILE(attributes->core.lifetime)) {
psa_crypto_prepare_transaction(PSA_CRYPTO_TRANSACTION_CREATE_KEY);
psa_crypto_transaction.key.lifetime = slot->attr.lifetime;
psa_crypto_transaction.key.slot = slot_number;
psa_crypto_transaction.key.id = slot->attr.id;
status = psa_crypto_save_transaction();
if (status != PSA_SUCCESS) {
(void) psa_crypto_stop_transaction();
return status;
}
}
status = psa_copy_key_material_into_slot(
slot, (uint8_t *) (&slot_number), sizeof(slot_number));
}
if (*p_drv == NULL && method == PSA_KEY_CREATION_REGISTER) {
/* Key registration only makes sense with a secure element. */
return PSA_ERROR_INVALID_ARGUMENT;
}
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
return PSA_SUCCESS;
}
/** Finalize the creation of a key once its key material has been set.
*
* This entails writing the key to persistent storage.
*
* If this function fails, call psa_fail_key_creation().
* See the documentation of psa_start_key_creation() for the intended use
* of this function.
*
* If the finalization succeeds, the function sets the key slot's state to
* PSA_SLOT_FULL, and the key slot can no longer be accessed as part of the
* key creation process.
*
* \param[in,out] slot Pointer to the slot with key material.
* \param[in] driver The secure element driver for the key,
* or NULL for a transparent key.
* \param[out] key On success, identifier of the key. Note that the
* key identifier is also stored in the key slot.
*
* \retval #PSA_SUCCESS
* The key was successfully created.
* \retval #PSA_ERROR_INSUFFICIENT_MEMORY \emptydescription
* \retval #PSA_ERROR_INSUFFICIENT_STORAGE \emptydescription
* \retval #PSA_ERROR_ALREADY_EXISTS \emptydescription
* \retval #PSA_ERROR_DATA_INVALID \emptydescription
* \retval #PSA_ERROR_DATA_CORRUPT \emptydescription
* \retval #PSA_ERROR_STORAGE_FAILURE \emptydescription
*
* \return If this function fails, the key slot is an invalid state.
* You must call psa_fail_key_creation() to wipe and free the slot.
*/
static psa_status_t psa_finish_key_creation(
psa_key_slot_t *slot,
psa_se_drv_table_entry_t *driver,
mbedtls_svc_key_id_t *key)
{
psa_status_t status = PSA_SUCCESS;
(void) slot;
(void) driver;
#if defined(MBEDTLS_PSA_CRYPTO_STORAGE_C)
if (!PSA_KEY_LIFETIME_IS_VOLATILE(slot->attr.lifetime)) {
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
if (driver != NULL) {
psa_se_key_data_storage_t data;
psa_key_slot_number_t slot_number =
psa_key_slot_get_slot_number(slot);
MBEDTLS_STATIC_ASSERT(sizeof(slot_number) ==
sizeof(data.slot_number),
"Slot number size does not match psa_se_key_data_storage_t");
memcpy(&data.slot_number, &slot_number, sizeof(slot_number));
status = psa_save_persistent_key(&slot->attr,
(uint8_t *) &data,
sizeof(data));
} else
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
{
/* Key material is saved in export representation in the slot, so
* just pass the slot buffer for storage. */
status = psa_save_persistent_key(&slot->attr,
slot->key.data,
slot->key.bytes);
}
}
#endif /* defined(MBEDTLS_PSA_CRYPTO_STORAGE_C) */
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
/* Finish the transaction for a key creation. This does not
* happen when registering an existing key. Detect this case
* by checking whether a transaction is in progress (actual
* creation of a persistent key in a secure element requires a transaction,
* but registration or volatile key creation doesn't use one). */
if (driver != NULL &&
psa_crypto_transaction.unknown.type == PSA_CRYPTO_TRANSACTION_CREATE_KEY) {
status = psa_save_se_persistent_data(driver);
if (status != PSA_SUCCESS) {
psa_destroy_persistent_key(slot->attr.id);
return status;
}
status = psa_crypto_stop_transaction();
}
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
if (status == PSA_SUCCESS) {
*key = slot->attr.id;
status = psa_key_slot_state_transition(slot, PSA_SLOT_FILLING,
PSA_SLOT_FULL);
if (status != PSA_SUCCESS) {
*key = MBEDTLS_SVC_KEY_ID_INIT;
}
}
return status;
}
/** Abort the creation of a key.
*
* You may call this function after calling psa_start_key_creation(),
* or after psa_finish_key_creation() fails. In other circumstances, this
* function may not clean up persistent storage.
* See the documentation of psa_start_key_creation() for the intended use
* of this function. Sets the slot's state to PSA_SLOT_EMPTY.
*
* \param[in,out] slot Pointer to the slot with key material.
* \param[in] driver The secure element driver for the key,
* or NULL for a transparent key.
*/
static void psa_fail_key_creation(psa_key_slot_t *slot,
psa_se_drv_table_entry_t *driver)
{
(void) driver;
if (slot == NULL) {
return;
}
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
/* TODO: If the key has already been created in the secure
* element, and the failure happened later (when saving metadata
* to internal storage), we need to destroy the key in the secure
* element.
* https://github.com/ARMmbed/mbed-crypto/issues/217
*/
/* Abort the ongoing transaction if any (there may not be one if
* the creation process failed before starting one, or if the
* key creation is a registration of a key in a secure element).
* Earlier functions must already have done what it takes to undo any
* partial creation. All that's left is to update the transaction data
* itself. */
(void) psa_crypto_stop_transaction();
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
psa_wipe_key_slot(slot);
}
/** Validate optional attributes during key creation.
*
* Some key attributes are optional during key creation. If they are
* specified in the attributes structure, check that they are consistent
* with the data in the slot.
*
* This function should be called near the end of key creation, after
* the slot in memory is fully populated but before saving persistent data.
*/
static psa_status_t psa_validate_optional_attributes(
const psa_key_slot_t *slot,
const psa_key_attributes_t *attributes)
{
if (attributes->core.type != 0) {
if (attributes->core.type != slot->attr.type) {
return PSA_ERROR_INVALID_ARGUMENT;
}
}
if (attributes->domain_parameters_size != 0) {
#if (defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) && \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT)) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY)
if (PSA_KEY_TYPE_IS_RSA(slot->attr.type)) {
mbedtls_rsa_context *rsa = NULL;
mbedtls_mpi actual, required;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
psa_status_t status = mbedtls_psa_rsa_load_representation(
slot->attr.type,
slot->key.data,
slot->key.bytes,
&rsa);
if (status != PSA_SUCCESS) {
return status;
}
mbedtls_mpi_init(&actual);
mbedtls_mpi_init(&required);
ret = mbedtls_rsa_export(rsa,
NULL, NULL, NULL, NULL, &actual);
mbedtls_rsa_free(rsa);
mbedtls_free(rsa);
if (ret != 0) {
goto rsa_exit;
}
ret = mbedtls_mpi_read_binary(&required,
attributes->domain_parameters,
attributes->domain_parameters_size);
if (ret != 0) {
goto rsa_exit;
}
if (mbedtls_mpi_cmp_mpi(&actual, &required) != 0) {
ret = MBEDTLS_ERR_RSA_BAD_INPUT_DATA;
}
rsa_exit:
mbedtls_mpi_free(&actual);
mbedtls_mpi_free(&required);
if (ret != 0) {
return mbedtls_to_psa_error(ret);
}
} else
#endif /* (defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) &&
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT)) ||
* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) */
{
return PSA_ERROR_INVALID_ARGUMENT;
}
}
if (attributes->core.bits != 0) {
if (attributes->core.bits != slot->attr.bits) {
return PSA_ERROR_INVALID_ARGUMENT;
}
}
return PSA_SUCCESS;
}
psa_status_t psa_import_key(const psa_key_attributes_t *attributes,
const uint8_t *data,
size_t data_length,
mbedtls_svc_key_id_t *key)
{
psa_status_t status;
psa_key_slot_t *slot = NULL;
psa_se_drv_table_entry_t *driver = NULL;
size_t bits;
size_t storage_size = data_length;
*key = MBEDTLS_SVC_KEY_ID_INIT;
/* Reject zero-length symmetric keys (including raw data key objects).
* This also rejects any key which might be encoded as an empty string,
* which is never valid. */
if (data_length == 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
/* Ensure that the bytes-to-bits conversion cannot overflow. */
if (data_length > SIZE_MAX / 8) {
return PSA_ERROR_NOT_SUPPORTED;
}
status = psa_start_key_creation(PSA_KEY_CREATION_IMPORT, attributes,
&slot, &driver);
if (status != PSA_SUCCESS) {
goto exit;
}
/* In the case of a transparent key or an opaque key stored in local
* storage ( thus not in the case of importing a key in a secure element
* with storage ( MBEDTLS_PSA_CRYPTO_SE_C ) ),we have to allocate a
* buffer to hold the imported key material. */
if (slot->key.data == NULL) {
if (psa_key_lifetime_is_external(attributes->core.lifetime)) {
status = psa_driver_wrapper_get_key_buffer_size_from_key_data(
attributes, data, data_length, &storage_size);
if (status != PSA_SUCCESS) {
goto exit;
}
}
status = psa_allocate_buffer_to_slot(slot, storage_size);
if (status != PSA_SUCCESS) {
goto exit;
}
}
bits = slot->attr.bits;
status = psa_driver_wrapper_import_key(attributes,
data, data_length,
slot->key.data,
slot->key.bytes,
&slot->key.bytes, &bits);
if (status != PSA_SUCCESS) {
goto exit;
}
if (slot->attr.bits == 0) {
slot->attr.bits = (psa_key_bits_t) bits;
} else if (bits != slot->attr.bits) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
/* Enforce a size limit, and in particular ensure that the bit
* size fits in its representation type.*/
if (bits > PSA_MAX_KEY_BITS) {
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
status = psa_validate_optional_attributes(slot, attributes);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_finish_key_creation(slot, driver, key);
exit:
if (status != PSA_SUCCESS) {
psa_fail_key_creation(slot, driver);
}
return status;
}
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
psa_status_t mbedtls_psa_register_se_key(
const psa_key_attributes_t *attributes)
{
psa_status_t status;
psa_key_slot_t *slot = NULL;
psa_se_drv_table_entry_t *driver = NULL;
mbedtls_svc_key_id_t key = MBEDTLS_SVC_KEY_ID_INIT;
/* Leaving attributes unspecified is not currently supported.
* It could make sense to query the key type and size from the
* secure element, but not all secure elements support this
* and the driver HAL doesn't currently support it. */
if (psa_get_key_type(attributes) == PSA_KEY_TYPE_NONE) {
return PSA_ERROR_NOT_SUPPORTED;
}
if (psa_get_key_bits(attributes) == 0) {
return PSA_ERROR_NOT_SUPPORTED;
}
status = psa_start_key_creation(PSA_KEY_CREATION_REGISTER, attributes,
&slot, &driver);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_finish_key_creation(slot, driver, &key);
exit:
if (status != PSA_SUCCESS) {
psa_fail_key_creation(slot, driver);
}
/* Registration doesn't keep the key in RAM. */
psa_close_key(key);
return status;
}
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
psa_status_t psa_copy_key(mbedtls_svc_key_id_t source_key,
const psa_key_attributes_t *specified_attributes,
mbedtls_svc_key_id_t *target_key)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *source_slot = NULL;
psa_key_slot_t *target_slot = NULL;
psa_key_attributes_t actual_attributes = *specified_attributes;
psa_se_drv_table_entry_t *driver = NULL;
size_t storage_size = 0;
*target_key = MBEDTLS_SVC_KEY_ID_INIT;
status = psa_get_and_lock_key_slot_with_policy(
source_key, &source_slot, PSA_KEY_USAGE_COPY, 0);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_validate_optional_attributes(source_slot,
specified_attributes);
if (status != PSA_SUCCESS) {
goto exit;
}
/* The target key type and number of bits have been validated by
* psa_validate_optional_attributes() to be either equal to zero or
* equal to the ones of the source key. So it is safe to inherit
* them from the source key now."
* */
actual_attributes.core.bits = source_slot->attr.bits;
actual_attributes.core.type = source_slot->attr.type;
status = psa_restrict_key_policy(source_slot->attr.type,
&actual_attributes.core.policy,
&source_slot->attr.policy);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_start_key_creation(PSA_KEY_CREATION_COPY, &actual_attributes,
&target_slot, &driver);
if (status != PSA_SUCCESS) {
goto exit;
}
if (PSA_KEY_LIFETIME_GET_LOCATION(target_slot->attr.lifetime) !=
PSA_KEY_LIFETIME_GET_LOCATION(source_slot->attr.lifetime)) {
/*
* If the source and target keys are stored in different locations,
* the source key would need to be exported as plaintext and re-imported
* in the other location. This has security implications which have not
* been fully mapped. For now, this can be achieved through
* appropriate API invocations from the application, if needed.
* */
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
/*
* When the source and target keys are within the same location,
* - For transparent keys it is a blind copy without any driver invocation,
* - For opaque keys this translates to an invocation of the drivers'
* copy_key entry point through the dispatch layer.
* */
if (psa_key_lifetime_is_external(actual_attributes.core.lifetime)) {
status = psa_driver_wrapper_get_key_buffer_size(&actual_attributes,
&storage_size);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_allocate_buffer_to_slot(target_slot, storage_size);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_driver_wrapper_copy_key(&actual_attributes,
source_slot->key.data,
source_slot->key.bytes,
target_slot->key.data,
target_slot->key.bytes,
&target_slot->key.bytes);
if (status != PSA_SUCCESS) {
goto exit;
}
} else {
status = psa_copy_key_material_into_slot(target_slot,
source_slot->key.data,
source_slot->key.bytes);
if (status != PSA_SUCCESS) {
goto exit;
}
}
status = psa_finish_key_creation(target_slot, driver, target_key);
exit:
if (status != PSA_SUCCESS) {
psa_fail_key_creation(target_slot, driver);
}
unlock_status = psa_unregister_read_under_mutex(source_slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
/****************************************************************/
/* Message digests */
/****************************************************************/
psa_status_t psa_hash_abort(psa_hash_operation_t *operation)
{
/* Aborting a non-active operation is allowed */
if (operation->id == 0) {
return PSA_SUCCESS;
}
psa_status_t status = psa_driver_wrapper_hash_abort(operation);
operation->id = 0;
return status;
}
psa_status_t psa_hash_setup(psa_hash_operation_t *operation,
psa_algorithm_t alg)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
/* A context must be freshly initialized before it can be set up. */
if (operation->id != 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (!PSA_ALG_IS_HASH(alg)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
/* Ensure all of the context is zeroized, since PSA_HASH_OPERATION_INIT only
* directly zeroes the int-sized dummy member of the context union. */
memset(&operation->ctx, 0, sizeof(operation->ctx));
status = psa_driver_wrapper_hash_setup(operation, alg);
exit:
if (status != PSA_SUCCESS) {
psa_hash_abort(operation);
}
return status;
}
psa_status_t psa_hash_update(psa_hash_operation_t *operation,
const uint8_t *input,
size_t input_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
/* Don't require hash implementations to behave correctly on a
* zero-length input, which may have an invalid pointer. */
if (input_length == 0) {
return PSA_SUCCESS;
}
status = psa_driver_wrapper_hash_update(operation, input, input_length);
exit:
if (status != PSA_SUCCESS) {
psa_hash_abort(operation);
}
return status;
}
psa_status_t psa_hash_finish(psa_hash_operation_t *operation,
uint8_t *hash,
size_t hash_size,
size_t *hash_length)
{
*hash_length = 0;
if (operation->id == 0) {
return PSA_ERROR_BAD_STATE;
}
psa_status_t status = psa_driver_wrapper_hash_finish(
operation, hash, hash_size, hash_length);
psa_hash_abort(operation);
return status;
}
psa_status_t psa_hash_verify(psa_hash_operation_t *operation,
const uint8_t *hash,
size_t hash_length)
{
uint8_t actual_hash[PSA_HASH_MAX_SIZE];
size_t actual_hash_length;
psa_status_t status = psa_hash_finish(
operation,
actual_hash, sizeof(actual_hash),
&actual_hash_length);
if (status != PSA_SUCCESS) {
goto exit;
}
if (actual_hash_length != hash_length) {
status = PSA_ERROR_INVALID_SIGNATURE;
goto exit;
}
if (mbedtls_ct_memcmp(hash, actual_hash, actual_hash_length) != 0) {
status = PSA_ERROR_INVALID_SIGNATURE;
}
exit:
mbedtls_platform_zeroize(actual_hash, sizeof(actual_hash));
if (status != PSA_SUCCESS) {
psa_hash_abort(operation);
}
return status;
}
psa_status_t psa_hash_compute(psa_algorithm_t alg,
const uint8_t *input, size_t input_length,
uint8_t *hash, size_t hash_size,
size_t *hash_length)
{
*hash_length = 0;
if (!PSA_ALG_IS_HASH(alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
return psa_driver_wrapper_hash_compute(alg, input, input_length,
hash, hash_size, hash_length);
}
psa_status_t psa_hash_compare(psa_algorithm_t alg,
const uint8_t *input, size_t input_length,
const uint8_t *hash, size_t hash_length)
{
uint8_t actual_hash[PSA_HASH_MAX_SIZE];
size_t actual_hash_length;
if (!PSA_ALG_IS_HASH(alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
psa_status_t status = psa_driver_wrapper_hash_compute(
alg, input, input_length,
actual_hash, sizeof(actual_hash),
&actual_hash_length);
if (status != PSA_SUCCESS) {
goto exit;
}
if (actual_hash_length != hash_length) {
status = PSA_ERROR_INVALID_SIGNATURE;
goto exit;
}
if (mbedtls_ct_memcmp(hash, actual_hash, actual_hash_length) != 0) {
status = PSA_ERROR_INVALID_SIGNATURE;
}
exit:
mbedtls_platform_zeroize(actual_hash, sizeof(actual_hash));
return status;
}
psa_status_t psa_hash_clone(const psa_hash_operation_t *source_operation,
psa_hash_operation_t *target_operation)
{
if (source_operation->id == 0 ||
target_operation->id != 0) {
return PSA_ERROR_BAD_STATE;
}
psa_status_t status = psa_driver_wrapper_hash_clone(source_operation,
target_operation);
if (status != PSA_SUCCESS) {
psa_hash_abort(target_operation);
}
return status;
}
/****************************************************************/
/* MAC */
/****************************************************************/
psa_status_t psa_mac_abort(psa_mac_operation_t *operation)
{
/* Aborting a non-active operation is allowed */
if (operation->id == 0) {
return PSA_SUCCESS;
}
psa_status_t status = psa_driver_wrapper_mac_abort(operation);
operation->mac_size = 0;
operation->is_sign = 0;
operation->id = 0;
return status;
}
static psa_status_t psa_mac_finalize_alg_and_key_validation(
psa_algorithm_t alg,
const psa_key_attributes_t *attributes,
uint8_t *mac_size)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_type_t key_type = psa_get_key_type(attributes);
size_t key_bits = psa_get_key_bits(attributes);
if (!PSA_ALG_IS_MAC(alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
/* Validate the combination of key type and algorithm */
status = psa_mac_key_can_do(alg, key_type);
if (status != PSA_SUCCESS) {
return status;
}
/* Get the output length for the algorithm and key combination */
*mac_size = PSA_MAC_LENGTH(key_type, key_bits, alg);
if (*mac_size < 4) {
/* A very short MAC is too short for security since it can be
* brute-forced. Ancient protocols with 32-bit MACs do exist,
* so we make this our minimum, even though 32 bits is still
* too small for security. */
return PSA_ERROR_NOT_SUPPORTED;
}
if (*mac_size > PSA_MAC_LENGTH(key_type, key_bits,
PSA_ALG_FULL_LENGTH_MAC(alg))) {
/* It's impossible to "truncate" to a larger length than the full length
* of the algorithm. */
return PSA_ERROR_INVALID_ARGUMENT;
}
if (*mac_size > PSA_MAC_MAX_SIZE) {
/* PSA_MAC_LENGTH returns the correct length even for a MAC algorithm
* that is disabled in the compile-time configuration. The result can
* therefore be larger than PSA_MAC_MAX_SIZE, which does take the
* configuration into account. In this case, force a return of
* PSA_ERROR_NOT_SUPPORTED here. Otherwise psa_mac_verify(), or
* psa_mac_compute(mac_size=PSA_MAC_MAX_SIZE), would return
* PSA_ERROR_BUFFER_TOO_SMALL for an unsupported algorithm whose MAC size
* is larger than PSA_MAC_MAX_SIZE, which is misleading and which breaks
* systematically generated tests. */
return PSA_ERROR_NOT_SUPPORTED;
}
return PSA_SUCCESS;
}
static psa_status_t psa_mac_setup(psa_mac_operation_t *operation,
mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
int is_sign)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot = NULL;
psa_key_attributes_t attributes;
/* A context must be freshly initialized before it can be set up. */
if (operation->id != 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
status = psa_get_and_lock_key_slot_with_policy(
key,
&slot,
is_sign ? PSA_KEY_USAGE_SIGN_MESSAGE : PSA_KEY_USAGE_VERIFY_MESSAGE,
alg);
if (status != PSA_SUCCESS) {
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
status = psa_mac_finalize_alg_and_key_validation(alg, &attributes,
&operation->mac_size);
if (status != PSA_SUCCESS) {
goto exit;
}
operation->is_sign = is_sign;
/* Dispatch the MAC setup call with validated input */
if (is_sign) {
status = psa_driver_wrapper_mac_sign_setup(operation,
&attributes,
slot->key.data,
slot->key.bytes,
alg);
} else {
status = psa_driver_wrapper_mac_verify_setup(operation,
&attributes,
slot->key.data,
slot->key.bytes,
alg);
}
exit:
if (status != PSA_SUCCESS) {
psa_mac_abort(operation);
}
unlock_status = psa_unregister_read(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
psa_status_t psa_mac_sign_setup(psa_mac_operation_t *operation,
mbedtls_svc_key_id_t key,
psa_algorithm_t alg)
{
return psa_mac_setup(operation, key, alg, 1);
}
psa_status_t psa_mac_verify_setup(psa_mac_operation_t *operation,
mbedtls_svc_key_id_t key,
psa_algorithm_t alg)
{
return psa_mac_setup(operation, key, alg, 0);
}
psa_status_t psa_mac_update(psa_mac_operation_t *operation,
const uint8_t *input,
size_t input_length)
{
if (operation->id == 0) {
return PSA_ERROR_BAD_STATE;
}
/* Don't require hash implementations to behave correctly on a
* zero-length input, which may have an invalid pointer. */
if (input_length == 0) {
return PSA_SUCCESS;
}
psa_status_t status = psa_driver_wrapper_mac_update(operation,
input, input_length);
if (status != PSA_SUCCESS) {
psa_mac_abort(operation);
}
return status;
}
psa_status_t psa_mac_sign_finish(psa_mac_operation_t *operation,
uint8_t *mac,
size_t mac_size,
size_t *mac_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t abort_status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (!operation->is_sign) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
/* Sanity check. This will guarantee that mac_size != 0 (and so mac != NULL)
* once all the error checks are done. */
if (operation->mac_size == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (mac_size < operation->mac_size) {
status = PSA_ERROR_BUFFER_TOO_SMALL;
goto exit;
}
status = psa_driver_wrapper_mac_sign_finish(operation,
mac, operation->mac_size,
mac_length);
exit:
/* In case of success, set the potential excess room in the output buffer
* to an invalid value, to avoid potentially leaking a longer MAC.
* In case of error, set the output length and content to a safe default,
* such that in case the caller misses an error check, the output would be
* an unachievable MAC.
*/
if (status != PSA_SUCCESS) {
*mac_length = mac_size;
operation->mac_size = 0;
}
psa_wipe_tag_output_buffer(mac, status, mac_size, *mac_length);
abort_status = psa_mac_abort(operation);
return status == PSA_SUCCESS ? abort_status : status;
}
psa_status_t psa_mac_verify_finish(psa_mac_operation_t *operation,
const uint8_t *mac,
size_t mac_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t abort_status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->is_sign) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->mac_size != mac_length) {
status = PSA_ERROR_INVALID_SIGNATURE;
goto exit;
}
status = psa_driver_wrapper_mac_verify_finish(operation,
mac, mac_length);
exit:
abort_status = psa_mac_abort(operation);
return status == PSA_SUCCESS ? abort_status : status;
}
static psa_status_t psa_mac_compute_internal(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *mac,
size_t mac_size,
size_t *mac_length,
int is_sign)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
uint8_t operation_mac_size = 0;
psa_key_attributes_t attributes;
status = psa_get_and_lock_key_slot_with_policy(
key,
&slot,
is_sign ? PSA_KEY_USAGE_SIGN_MESSAGE : PSA_KEY_USAGE_VERIFY_MESSAGE,
alg);
if (status != PSA_SUCCESS) {
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
status = psa_mac_finalize_alg_and_key_validation(alg, &attributes,
&operation_mac_size);
if (status != PSA_SUCCESS) {
goto exit;
}
if (mac_size < operation_mac_size) {
status = PSA_ERROR_BUFFER_TOO_SMALL;
goto exit;
}
status = psa_driver_wrapper_mac_compute(
&attributes,
slot->key.data, slot->key.bytes,
alg,
input, input_length,
mac, operation_mac_size, mac_length);
exit:
/* In case of success, set the potential excess room in the output buffer
* to an invalid value, to avoid potentially leaking a longer MAC.
* In case of error, set the output length and content to a safe default,
* such that in case the caller misses an error check, the output would be
* an unachievable MAC.
*/
if (status != PSA_SUCCESS) {
*mac_length = mac_size;
operation_mac_size = 0;
}
psa_wipe_tag_output_buffer(mac, status, mac_size, *mac_length);
unlock_status = psa_unregister_read_under_mutex(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
psa_status_t psa_mac_compute(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *mac,
size_t mac_size,
size_t *mac_length)
{
return psa_mac_compute_internal(key, alg,
input, input_length,
mac, mac_size, mac_length, 1);
}
psa_status_t psa_mac_verify(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
const uint8_t *mac,
size_t mac_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
uint8_t actual_mac[PSA_MAC_MAX_SIZE];
size_t actual_mac_length;
status = psa_mac_compute_internal(key, alg,
input, input_length,
actual_mac, sizeof(actual_mac),
&actual_mac_length, 0);
if (status != PSA_SUCCESS) {
goto exit;
}
if (mac_length != actual_mac_length) {
status = PSA_ERROR_INVALID_SIGNATURE;
goto exit;
}
if (mbedtls_ct_memcmp(mac, actual_mac, actual_mac_length) != 0) {
status = PSA_ERROR_INVALID_SIGNATURE;
goto exit;
}
exit:
mbedtls_platform_zeroize(actual_mac, sizeof(actual_mac));
return status;
}
/****************************************************************/
/* Asymmetric cryptography */
/****************************************************************/
static psa_status_t psa_sign_verify_check_alg(int input_is_message,
psa_algorithm_t alg)
{
if (input_is_message) {
if (!PSA_ALG_IS_SIGN_MESSAGE(alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
if (PSA_ALG_IS_SIGN_HASH(alg)) {
if (!PSA_ALG_IS_HASH(PSA_ALG_SIGN_GET_HASH(alg))) {
return PSA_ERROR_INVALID_ARGUMENT;
}
}
} else {
if (!PSA_ALG_IS_SIGN_HASH(alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
}
return PSA_SUCCESS;
}
static psa_status_t psa_sign_internal(mbedtls_svc_key_id_t key,
int input_is_message,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *signature,
size_t signature_size,
size_t *signature_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
psa_key_attributes_t attributes;
*signature_length = 0;
status = psa_sign_verify_check_alg(input_is_message, alg);
if (status != PSA_SUCCESS) {
return status;
}
/* Immediately reject a zero-length signature buffer. This guarantees
* that signature must be a valid pointer. (On the other hand, the input
* buffer can in principle be empty since it doesn't actually have
* to be a hash.) */
if (signature_size == 0) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
status = psa_get_and_lock_key_slot_with_policy(
key, &slot,
input_is_message ? PSA_KEY_USAGE_SIGN_MESSAGE :
PSA_KEY_USAGE_SIGN_HASH,
alg);
if (status != PSA_SUCCESS) {
goto exit;
}
if (!PSA_KEY_TYPE_IS_KEY_PAIR(slot->attr.type)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
if (input_is_message) {
status = psa_driver_wrapper_sign_message(
&attributes, slot->key.data, slot->key.bytes,
alg, input, input_length,
signature, signature_size, signature_length);
} else {
status = psa_driver_wrapper_sign_hash(
&attributes, slot->key.data, slot->key.bytes,
alg, input, input_length,
signature, signature_size, signature_length);
}
exit:
psa_wipe_tag_output_buffer(signature, status, signature_size,
*signature_length);
unlock_status = psa_unregister_read_under_mutex(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
static psa_status_t psa_verify_internal(mbedtls_svc_key_id_t key,
int input_is_message,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
const uint8_t *signature,
size_t signature_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
status = psa_sign_verify_check_alg(input_is_message, alg);
if (status != PSA_SUCCESS) {
return status;
}
status = psa_get_and_lock_key_slot_with_policy(
key, &slot,
input_is_message ? PSA_KEY_USAGE_VERIFY_MESSAGE :
PSA_KEY_USAGE_VERIFY_HASH,
alg);
if (status != PSA_SUCCESS) {
return status;
}
psa_key_attributes_t attributes = {
.core = slot->attr
};
if (input_is_message) {
status = psa_driver_wrapper_verify_message(
&attributes, slot->key.data, slot->key.bytes,
alg, input, input_length,
signature, signature_length);
} else {
status = psa_driver_wrapper_verify_hash(
&attributes, slot->key.data, slot->key.bytes,
alg, input, input_length,
signature, signature_length);
}
unlock_status = psa_unregister_read_under_mutex(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
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)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (PSA_ALG_IS_SIGN_HASH(alg)) {
size_t hash_length;
uint8_t hash[PSA_HASH_MAX_SIZE];
status = psa_driver_wrapper_hash_compute(
PSA_ALG_SIGN_GET_HASH(alg),
input, input_length,
hash, sizeof(hash), &hash_length);
if (status != PSA_SUCCESS) {
return status;
}
return psa_driver_wrapper_sign_hash(
attributes, key_buffer, key_buffer_size,
alg, hash, hash_length,
signature, signature_size, signature_length);
}
return PSA_ERROR_NOT_SUPPORTED;
}
psa_status_t psa_sign_message(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *signature,
size_t signature_size,
size_t *signature_length)
{
return psa_sign_internal(
key, 1, alg, input, input_length,
signature, signature_size, signature_length);
}
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)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (PSA_ALG_IS_SIGN_HASH(alg)) {
size_t hash_length;
uint8_t hash[PSA_HASH_MAX_SIZE];
status = psa_driver_wrapper_hash_compute(
PSA_ALG_SIGN_GET_HASH(alg),
input, input_length,
hash, sizeof(hash), &hash_length);
if (status != PSA_SUCCESS) {
return status;
}
return psa_driver_wrapper_verify_hash(
attributes, key_buffer, key_buffer_size,
alg, hash, hash_length,
signature, signature_length);
}
return PSA_ERROR_NOT_SUPPORTED;
}
psa_status_t psa_verify_message(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
const uint8_t *signature,
size_t signature_length)
{
return psa_verify_internal(
key, 1, alg, input, input_length,
signature, signature_length);
}
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)
{
if (attributes->core.type == PSA_KEY_TYPE_RSA_KEY_PAIR) {
if (PSA_ALG_IS_RSA_PKCS1V15_SIGN(alg) ||
PSA_ALG_IS_RSA_PSS(alg)) {
#if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS)
return mbedtls_psa_rsa_sign_hash(
attributes,
key_buffer, key_buffer_size,
alg, hash, hash_length,
signature, signature_size, signature_length);
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS) */
} else {
return PSA_ERROR_INVALID_ARGUMENT;
}
} else if (PSA_KEY_TYPE_IS_ECC(attributes->core.type)) {
if (PSA_ALG_IS_ECDSA(alg)) {
#if defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)
return mbedtls_psa_ecdsa_sign_hash(
attributes,
key_buffer, key_buffer_size,
alg, hash, hash_length,
signature, signature_size, signature_length);
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) */
} else {
return PSA_ERROR_INVALID_ARGUMENT;
}
}
(void) key_buffer;
(void) key_buffer_size;
(void) hash;
(void) hash_length;
(void) signature;
(void) signature_size;
(void) signature_length;
return PSA_ERROR_NOT_SUPPORTED;
}
psa_status_t psa_sign_hash(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *hash,
size_t hash_length,
uint8_t *signature,
size_t signature_size,
size_t *signature_length)
{
return psa_sign_internal(
key, 0, alg, hash, hash_length,
signature, signature_size, signature_length);
}
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)
{
if (PSA_KEY_TYPE_IS_RSA(attributes->core.type)) {
if (PSA_ALG_IS_RSA_PKCS1V15_SIGN(alg) ||
PSA_ALG_IS_RSA_PSS(alg)) {
#if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS)
return mbedtls_psa_rsa_verify_hash(
attributes,
key_buffer, key_buffer_size,
alg, hash, hash_length,
signature, signature_length);
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS) */
} else {
return PSA_ERROR_INVALID_ARGUMENT;
}
} else if (PSA_KEY_TYPE_IS_ECC(attributes->core.type)) {
if (PSA_ALG_IS_ECDSA(alg)) {
#if defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)
return mbedtls_psa_ecdsa_verify_hash(
attributes,
key_buffer, key_buffer_size,
alg, hash, hash_length,
signature, signature_length);
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) */
} else {
return PSA_ERROR_INVALID_ARGUMENT;
}
}
(void) key_buffer;
(void) key_buffer_size;
(void) hash;
(void) hash_length;
(void) signature;
(void) signature_length;
return PSA_ERROR_NOT_SUPPORTED;
}
psa_status_t psa_verify_hash(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *hash,
size_t hash_length,
const uint8_t *signature,
size_t signature_length)
{
return psa_verify_internal(
key, 0, alg, hash, hash_length,
signature, signature_length);
}
psa_status_t psa_asymmetric_encrypt(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
const uint8_t *salt,
size_t salt_length,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
psa_key_attributes_t attributes;
(void) input;
(void) input_length;
(void) salt;
(void) output;
(void) output_size;
*output_length = 0;
if (!PSA_ALG_IS_RSA_OAEP(alg) && salt_length != 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
status = psa_get_and_lock_key_slot_with_policy(
key, &slot, PSA_KEY_USAGE_ENCRYPT, alg);
if (status != PSA_SUCCESS) {
return status;
}
if (!(PSA_KEY_TYPE_IS_PUBLIC_KEY(slot->attr.type) ||
PSA_KEY_TYPE_IS_KEY_PAIR(slot->attr.type))) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
status = psa_driver_wrapper_asymmetric_encrypt(
&attributes, slot->key.data, slot->key.bytes,
alg, input, input_length, salt, salt_length,
output, output_size, output_length);
exit:
unlock_status = psa_unregister_read_under_mutex(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
psa_status_t psa_asymmetric_decrypt(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
const uint8_t *salt,
size_t salt_length,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
psa_key_attributes_t attributes;
(void) input;
(void) input_length;
(void) salt;
(void) output;
(void) output_size;
*output_length = 0;
if (!PSA_ALG_IS_RSA_OAEP(alg) && salt_length != 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
status = psa_get_and_lock_key_slot_with_policy(
key, &slot, PSA_KEY_USAGE_DECRYPT, alg);
if (status != PSA_SUCCESS) {
return status;
}
if (!PSA_KEY_TYPE_IS_KEY_PAIR(slot->attr.type)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
status = psa_driver_wrapper_asymmetric_decrypt(
&attributes, slot->key.data, slot->key.bytes,
alg, input, input_length, salt, salt_length,
output, output_size, output_length);
exit:
unlock_status = psa_unregister_read_under_mutex(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
/****************************************************************/
/* Asymmetric interruptible cryptography */
/****************************************************************/
static uint32_t psa_interruptible_max_ops = PSA_INTERRUPTIBLE_MAX_OPS_UNLIMITED;
void psa_interruptible_set_max_ops(uint32_t max_ops)
{
psa_interruptible_max_ops = max_ops;
}
uint32_t psa_interruptible_get_max_ops(void)
{
return psa_interruptible_max_ops;
}
uint32_t psa_sign_hash_get_num_ops(
const psa_sign_hash_interruptible_operation_t *operation)
{
return operation->num_ops;
}
uint32_t psa_verify_hash_get_num_ops(
const psa_verify_hash_interruptible_operation_t *operation)
{
return operation->num_ops;
}
static psa_status_t psa_sign_hash_abort_internal(
psa_sign_hash_interruptible_operation_t *operation)
{
if (operation->id == 0) {
/* The object has (apparently) been initialized but it is not (yet)
* in use. It's ok to call abort on such an object, and there's
* nothing to do. */
return PSA_SUCCESS;
}
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
status = psa_driver_wrapper_sign_hash_abort(operation);
operation->id = 0;
/* Do not clear either the error_occurred or num_ops elements here as they
* only want to be cleared by the application calling abort, not by abort
* being called at completion of an operation. */
return status;
}
psa_status_t psa_sign_hash_start(
psa_sign_hash_interruptible_operation_t *operation,
mbedtls_svc_key_id_t key, psa_algorithm_t alg,
const uint8_t *hash, size_t hash_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
psa_key_attributes_t attributes;
/* Check that start has not been previously called, or operation has not
* previously errored. */
if (operation->id != 0 || operation->error_occurred) {
return PSA_ERROR_BAD_STATE;
}
status = psa_sign_verify_check_alg(0, alg);
if (status != PSA_SUCCESS) {
operation->error_occurred = 1;
return status;
}
status = psa_get_and_lock_key_slot_with_policy(key, &slot,
PSA_KEY_USAGE_SIGN_HASH,
alg);
if (status != PSA_SUCCESS) {
goto exit;
}
if (!PSA_KEY_TYPE_IS_KEY_PAIR(slot->attr.type)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
/* Ensure ops count gets reset, in case of operation re-use. */
operation->num_ops = 0;
status = psa_driver_wrapper_sign_hash_start(operation, &attributes,
slot->key.data,
slot->key.bytes, alg,
hash, hash_length);
exit:
if (status != PSA_SUCCESS) {
operation->error_occurred = 1;
psa_sign_hash_abort_internal(operation);
}
unlock_status = psa_unregister_read(slot);
if (unlock_status != PSA_SUCCESS) {
operation->error_occurred = 1;
}
return (status == PSA_SUCCESS) ? unlock_status : status;
}
psa_status_t psa_sign_hash_complete(
psa_sign_hash_interruptible_operation_t *operation,
uint8_t *signature, size_t signature_size,
size_t *signature_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
*signature_length = 0;
/* Check that start has been called first, and that operation has not
* previously errored. */
if (operation->id == 0 || operation->error_occurred) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
/* Immediately reject a zero-length signature buffer. This guarantees that
* signature must be a valid pointer. */
if (signature_size == 0) {
status = PSA_ERROR_BUFFER_TOO_SMALL;
goto exit;
}
status = psa_driver_wrapper_sign_hash_complete(operation, signature,
signature_size,
signature_length);
/* Update ops count with work done. */
operation->num_ops = psa_driver_wrapper_sign_hash_get_num_ops(operation);
exit:
psa_wipe_tag_output_buffer(signature, status, signature_size,
*signature_length);
if (status != PSA_OPERATION_INCOMPLETE) {
if (status != PSA_SUCCESS) {
operation->error_occurred = 1;
}
psa_sign_hash_abort_internal(operation);
}
return status;
}
psa_status_t psa_sign_hash_abort(
psa_sign_hash_interruptible_operation_t *operation)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
status = psa_sign_hash_abort_internal(operation);
/* We clear the number of ops done here, so that it is not cleared when
* the operation fails or succeeds, only on manual abort. */
operation->num_ops = 0;
/* Likewise, failure state. */
operation->error_occurred = 0;
return status;
}
static psa_status_t psa_verify_hash_abort_internal(
psa_verify_hash_interruptible_operation_t *operation)
{
if (operation->id == 0) {
/* The object has (apparently) been initialized but it is not (yet)
* in use. It's ok to call abort on such an object, and there's
* nothing to do. */
return PSA_SUCCESS;
}
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
status = psa_driver_wrapper_verify_hash_abort(operation);
operation->id = 0;
/* Do not clear either the error_occurred or num_ops elements here as they
* only want to be cleared by the application calling abort, not by abort
* being called at completion of an operation. */
return status;
}
psa_status_t psa_verify_hash_start(
psa_verify_hash_interruptible_operation_t *operation,
mbedtls_svc_key_id_t key, psa_algorithm_t alg,
const uint8_t *hash, size_t hash_length,
const uint8_t *signature, size_t signature_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
/* Check that start has not been previously called, or operation has not
* previously errored. */
if (operation->id != 0 || operation->error_occurred) {
return PSA_ERROR_BAD_STATE;
}
status = psa_sign_verify_check_alg(0, alg);
if (status != PSA_SUCCESS) {
operation->error_occurred = 1;
return status;
}
status = psa_get_and_lock_key_slot_with_policy(key, &slot,
PSA_KEY_USAGE_VERIFY_HASH,
alg);
if (status != PSA_SUCCESS) {
operation->error_occurred = 1;
return status;
}
psa_key_attributes_t attributes = {
.core = slot->attr
};
/* Ensure ops count gets reset, in case of operation re-use. */
operation->num_ops = 0;
status = psa_driver_wrapper_verify_hash_start(operation, &attributes,
slot->key.data,
slot->key.bytes,
alg, hash, hash_length,
signature, signature_length);
if (status != PSA_SUCCESS) {
operation->error_occurred = 1;
psa_verify_hash_abort_internal(operation);
}
unlock_status = psa_unregister_read(slot);
if (unlock_status != PSA_SUCCESS) {
operation->error_occurred = 1;
}
return (status == PSA_SUCCESS) ? unlock_status : status;
}
psa_status_t psa_verify_hash_complete(
psa_verify_hash_interruptible_operation_t *operation)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
/* Check that start has been called first, and that operation has not
* previously errored. */
if (operation->id == 0 || operation->error_occurred) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
status = psa_driver_wrapper_verify_hash_complete(operation);
/* Update ops count with work done. */
operation->num_ops = psa_driver_wrapper_verify_hash_get_num_ops(
operation);
exit:
if (status != PSA_OPERATION_INCOMPLETE) {
if (status != PSA_SUCCESS) {
operation->error_occurred = 1;
}
psa_verify_hash_abort_internal(operation);
}
return status;
}
psa_status_t psa_verify_hash_abort(
psa_verify_hash_interruptible_operation_t *operation)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
status = psa_verify_hash_abort_internal(operation);
/* We clear the number of ops done here, so that it is not cleared when
* the operation fails or succeeds, only on manual abort. */
operation->num_ops = 0;
/* Likewise, failure state. */
operation->error_occurred = 0;
return status;
}
/****************************************************************/
/* Asymmetric interruptible cryptography internal */
/* implementations */
/****************************************************************/
void mbedtls_psa_interruptible_set_max_ops(uint32_t max_ops)
{
#if (defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)) && \
defined(MBEDTLS_ECP_RESTARTABLE)
/* Internal implementation uses zero to indicate infinite number max ops,
* therefore avoid this value, and set to minimum possible. */
if (max_ops == 0) {
max_ops = 1;
}
mbedtls_ecp_set_max_ops(max_ops);
#else
(void) max_ops;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) &&
* defined( MBEDTLS_ECP_RESTARTABLE ) */
}
uint32_t mbedtls_psa_sign_hash_get_num_ops(
const mbedtls_psa_sign_hash_interruptible_operation_t *operation)
{
#if (defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)) && \
defined(MBEDTLS_ECP_RESTARTABLE)
return operation->num_ops;
#else
(void) operation;
return 0;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) &&
* defined( MBEDTLS_ECP_RESTARTABLE ) */
}
uint32_t mbedtls_psa_verify_hash_get_num_ops(
const mbedtls_psa_verify_hash_interruptible_operation_t *operation)
{
#if (defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)) && \
defined(MBEDTLS_ECP_RESTARTABLE)
return operation->num_ops;
#else
(void) operation;
return 0;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) &&
* defined( MBEDTLS_ECP_RESTARTABLE ) */
}
psa_status_t mbedtls_psa_sign_hash_start(
mbedtls_psa_sign_hash_interruptible_operation_t *operation,
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)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t required_hash_length;
if (!PSA_KEY_TYPE_IS_ECC(attributes->core.type)) {
return PSA_ERROR_NOT_SUPPORTED;
}
if (!PSA_ALG_IS_ECDSA(alg)) {
return PSA_ERROR_NOT_SUPPORTED;
}
#if (defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)) && \
defined(MBEDTLS_ECP_RESTARTABLE)
mbedtls_ecdsa_restart_init(&operation->restart_ctx);
/* Ensure num_ops is zero'ed in case of context re-use. */
operation->num_ops = 0;
status = mbedtls_psa_ecp_load_representation(attributes->core.type,
attributes->core.bits,
key_buffer,
key_buffer_size,
&operation->ctx);
if (status != PSA_SUCCESS) {
return status;
}
operation->coordinate_bytes = PSA_BITS_TO_BYTES(
operation->ctx->grp.nbits);
psa_algorithm_t hash_alg = PSA_ALG_SIGN_GET_HASH(alg);
operation->md_alg = mbedtls_md_type_from_psa_alg(hash_alg);
operation->alg = alg;
/* We only need to store the same length of hash as the private key size
* here, it would be truncated by the internal implementation anyway. */
required_hash_length = (hash_length < operation->coordinate_bytes ?
hash_length : operation->coordinate_bytes);
if (required_hash_length > sizeof(operation->hash)) {
/* Shouldn't happen, but better safe than sorry. */
return PSA_ERROR_CORRUPTION_DETECTED;
}
memcpy(operation->hash, hash, required_hash_length);
operation->hash_length = required_hash_length;
return PSA_SUCCESS;
#else
(void) operation;
(void) key_buffer;
(void) key_buffer_size;
(void) alg;
(void) hash;
(void) hash_length;
(void) status;
(void) required_hash_length;
return PSA_ERROR_NOT_SUPPORTED;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) &&
* defined( MBEDTLS_ECP_RESTARTABLE ) */
}
psa_status_t mbedtls_psa_sign_hash_complete(
mbedtls_psa_sign_hash_interruptible_operation_t *operation,
uint8_t *signature, size_t signature_size,
size_t *signature_length)
{
#if (defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)) && \
defined(MBEDTLS_ECP_RESTARTABLE)
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
mbedtls_mpi r;
mbedtls_mpi s;
mbedtls_mpi_init(&r);
mbedtls_mpi_init(&s);
/* Ensure max_ops is set to the current value (or default). */
mbedtls_psa_interruptible_set_max_ops(psa_interruptible_get_max_ops());
if (signature_size < 2 * operation->coordinate_bytes) {
status = PSA_ERROR_BUFFER_TOO_SMALL;
goto exit;
}
if (PSA_ALG_ECDSA_IS_DETERMINISTIC(operation->alg)) {
#if defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)
status = mbedtls_to_psa_error(
mbedtls_ecdsa_sign_det_restartable(&operation->ctx->grp,
&r,
&s,
&operation->ctx->d,
operation->hash,
operation->hash_length,
operation->md_alg,
mbedtls_psa_get_random,
MBEDTLS_PSA_RANDOM_STATE,
&operation->restart_ctx));
#else /* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) */
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) */
} else {
status = mbedtls_to_psa_error(
mbedtls_ecdsa_sign_restartable(&operation->ctx->grp,
&r,
&s,
&operation->ctx->d,
operation->hash,
operation->hash_length,
mbedtls_psa_get_random,
MBEDTLS_PSA_RANDOM_STATE,
mbedtls_psa_get_random,
MBEDTLS_PSA_RANDOM_STATE,
&operation->restart_ctx));
}
/* Hide the fact that the restart context only holds a delta of number of
* ops done during the last operation, not an absolute value. */
operation->num_ops += operation->restart_ctx.ecp.ops_done;
if (status == PSA_SUCCESS) {
status = mbedtls_to_psa_error(
mbedtls_mpi_write_binary(&r,
signature,
operation->coordinate_bytes)
);
if (status != PSA_SUCCESS) {
goto exit;
}
status = mbedtls_to_psa_error(
mbedtls_mpi_write_binary(&s,
signature +
operation->coordinate_bytes,
operation->coordinate_bytes)
);
if (status != PSA_SUCCESS) {
goto exit;
}
*signature_length = operation->coordinate_bytes * 2;
status = PSA_SUCCESS;
}
exit:
mbedtls_mpi_free(&r);
mbedtls_mpi_free(&s);
return status;
#else
(void) operation;
(void) signature;
(void) signature_size;
(void) signature_length;
return PSA_ERROR_NOT_SUPPORTED;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) &&
* defined( MBEDTLS_ECP_RESTARTABLE ) */
}
psa_status_t mbedtls_psa_sign_hash_abort(
mbedtls_psa_sign_hash_interruptible_operation_t *operation)
{
#if (defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)) && \
defined(MBEDTLS_ECP_RESTARTABLE)
if (operation->ctx) {
mbedtls_ecdsa_free(operation->ctx);
mbedtls_free(operation->ctx);
operation->ctx = NULL;
}
mbedtls_ecdsa_restart_free(&operation->restart_ctx);
operation->num_ops = 0;
return PSA_SUCCESS;
#else
(void) operation;
return PSA_ERROR_NOT_SUPPORTED;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) &&
* defined( MBEDTLS_ECP_RESTARTABLE ) */
}
psa_status_t mbedtls_psa_verify_hash_start(
mbedtls_psa_verify_hash_interruptible_operation_t *operation,
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)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t coordinate_bytes = 0;
size_t required_hash_length = 0;
if (!PSA_KEY_TYPE_IS_ECC(attributes->core.type)) {
return PSA_ERROR_NOT_SUPPORTED;
}
if (!PSA_ALG_IS_ECDSA(alg)) {
return PSA_ERROR_NOT_SUPPORTED;
}
#if (defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)) && \
defined(MBEDTLS_ECP_RESTARTABLE)
mbedtls_ecdsa_restart_init(&operation->restart_ctx);
mbedtls_mpi_init(&operation->r);
mbedtls_mpi_init(&operation->s);
/* Ensure num_ops is zero'ed in case of context re-use. */
operation->num_ops = 0;
status = mbedtls_psa_ecp_load_representation(attributes->core.type,
attributes->core.bits,
key_buffer,
key_buffer_size,
&operation->ctx);
if (status != PSA_SUCCESS) {
return status;
}
coordinate_bytes = PSA_BITS_TO_BYTES(operation->ctx->grp.nbits);
if (signature_length != 2 * coordinate_bytes) {
return PSA_ERROR_INVALID_SIGNATURE;
}
status = mbedtls_to_psa_error(
mbedtls_mpi_read_binary(&operation->r,
signature,
coordinate_bytes));
if (status != PSA_SUCCESS) {
return status;
}
status = mbedtls_to_psa_error(
mbedtls_mpi_read_binary(&operation->s,
signature +
coordinate_bytes,
coordinate_bytes));
if (status != PSA_SUCCESS) {
return status;
}
status = mbedtls_psa_ecp_load_public_part(operation->ctx);
if (status != PSA_SUCCESS) {
return status;
}
/* We only need to store the same length of hash as the private key size
* here, it would be truncated by the internal implementation anyway. */
required_hash_length = (hash_length < coordinate_bytes ? hash_length :
coordinate_bytes);
if (required_hash_length > sizeof(operation->hash)) {
/* Shouldn't happen, but better safe than sorry. */
return PSA_ERROR_CORRUPTION_DETECTED;
}
memcpy(operation->hash, hash, required_hash_length);
operation->hash_length = required_hash_length;
return PSA_SUCCESS;
#else
(void) operation;
(void) key_buffer;
(void) key_buffer_size;
(void) alg;
(void) hash;
(void) hash_length;
(void) signature;
(void) signature_length;
(void) status;
(void) coordinate_bytes;
(void) required_hash_length;
return PSA_ERROR_NOT_SUPPORTED;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) &&
* defined( MBEDTLS_ECP_RESTARTABLE ) */
}
psa_status_t mbedtls_psa_verify_hash_complete(
mbedtls_psa_verify_hash_interruptible_operation_t *operation)
{
#if (defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)) && \
defined(MBEDTLS_ECP_RESTARTABLE)
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
/* Ensure max_ops is set to the current value (or default). */
mbedtls_psa_interruptible_set_max_ops(psa_interruptible_get_max_ops());
status = mbedtls_to_psa_error(
mbedtls_ecdsa_verify_restartable(&operation->ctx->grp,
operation->hash,
operation->hash_length,
&operation->ctx->Q,
&operation->r,
&operation->s,
&operation->restart_ctx));
/* Hide the fact that the restart context only holds a delta of number of
* ops done during the last operation, not an absolute value. */
operation->num_ops += operation->restart_ctx.ecp.ops_done;
return status;
#else
(void) operation;
return PSA_ERROR_NOT_SUPPORTED;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) &&
* defined( MBEDTLS_ECP_RESTARTABLE ) */
}
psa_status_t mbedtls_psa_verify_hash_abort(
mbedtls_psa_verify_hash_interruptible_operation_t *operation)
{
#if (defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA)) && \
defined(MBEDTLS_ECP_RESTARTABLE)
if (operation->ctx) {
mbedtls_ecdsa_free(operation->ctx);
mbedtls_free(operation->ctx);
operation->ctx = NULL;
}
mbedtls_ecdsa_restart_free(&operation->restart_ctx);
operation->num_ops = 0;
mbedtls_mpi_free(&operation->r);
mbedtls_mpi_free(&operation->s);
return PSA_SUCCESS;
#else
(void) operation;
return PSA_ERROR_NOT_SUPPORTED;
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_ECDSA) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_DETERMINISTIC_ECDSA) &&
* defined( MBEDTLS_ECP_RESTARTABLE ) */
}
/****************************************************************/
/* Symmetric cryptography */
/****************************************************************/
static psa_status_t psa_cipher_setup(psa_cipher_operation_t *operation,
mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
mbedtls_operation_t cipher_operation)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot = NULL;
psa_key_usage_t usage = (cipher_operation == MBEDTLS_ENCRYPT ?
PSA_KEY_USAGE_ENCRYPT :
PSA_KEY_USAGE_DECRYPT);
psa_key_attributes_t attributes;
/* A context must be freshly initialized before it can be set up. */
if (operation->id != 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (!PSA_ALG_IS_CIPHER(alg)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
status = psa_get_and_lock_key_slot_with_policy(key, &slot, usage, alg);
if (status != PSA_SUCCESS) {
goto exit;
}
/* Initialize the operation struct members, except for id. The id member
* is used to indicate to psa_cipher_abort that there are resources to free,
* so we only set it (in the driver wrapper) after resources have been
* allocated/initialized. */
operation->iv_set = 0;
if (alg == PSA_ALG_ECB_NO_PADDING) {
operation->iv_required = 0;
} else {
operation->iv_required = 1;
}
operation->default_iv_length = PSA_CIPHER_IV_LENGTH(slot->attr.type, alg);
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
/* Try doing the operation through a driver before using software fallback. */
if (cipher_operation == MBEDTLS_ENCRYPT) {
status = psa_driver_wrapper_cipher_encrypt_setup(operation,
&attributes,
slot->key.data,
slot->key.bytes,
alg);
} else {
status = psa_driver_wrapper_cipher_decrypt_setup(operation,
&attributes,
slot->key.data,
slot->key.bytes,
alg);
}
exit:
if (status != PSA_SUCCESS) {
psa_cipher_abort(operation);
}
unlock_status = psa_unregister_read(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
psa_status_t psa_cipher_encrypt_setup(psa_cipher_operation_t *operation,
mbedtls_svc_key_id_t key,
psa_algorithm_t alg)
{
return psa_cipher_setup(operation, key, alg, MBEDTLS_ENCRYPT);
}
psa_status_t psa_cipher_decrypt_setup(psa_cipher_operation_t *operation,
mbedtls_svc_key_id_t key,
psa_algorithm_t alg)
{
return psa_cipher_setup(operation, key, alg, MBEDTLS_DECRYPT);
}
psa_status_t psa_cipher_generate_iv(psa_cipher_operation_t *operation,
uint8_t *iv,
size_t iv_size,
size_t *iv_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
uint8_t local_iv[PSA_CIPHER_IV_MAX_SIZE];
size_t default_iv_length = 0;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->iv_set || !operation->iv_required) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
default_iv_length = operation->default_iv_length;
if (iv_size < default_iv_length) {
status = PSA_ERROR_BUFFER_TOO_SMALL;
goto exit;
}
if (default_iv_length > PSA_CIPHER_IV_MAX_SIZE) {
status = PSA_ERROR_GENERIC_ERROR;
goto exit;
}
status = psa_generate_random(local_iv, default_iv_length);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_driver_wrapper_cipher_set_iv(operation,
local_iv, default_iv_length);
exit:
if (status == PSA_SUCCESS) {
memcpy(iv, local_iv, default_iv_length);
*iv_length = default_iv_length;
operation->iv_set = 1;
} else {
*iv_length = 0;
psa_cipher_abort(operation);
}
return status;
}
psa_status_t psa_cipher_set_iv(psa_cipher_operation_t *operation,
const uint8_t *iv,
size_t iv_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->iv_set || !operation->iv_required) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (iv_length > PSA_CIPHER_IV_MAX_SIZE) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
status = psa_driver_wrapper_cipher_set_iv(operation,
iv,
iv_length);
exit:
if (status == PSA_SUCCESS) {
operation->iv_set = 1;
} else {
psa_cipher_abort(operation);
}
return status;
}
psa_status_t psa_cipher_update(psa_cipher_operation_t *operation,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->iv_required && !operation->iv_set) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
status = psa_driver_wrapper_cipher_update(operation,
input,
input_length,
output,
output_size,
output_length);
exit:
if (status != PSA_SUCCESS) {
psa_cipher_abort(operation);
}
return status;
}
psa_status_t psa_cipher_finish(psa_cipher_operation_t *operation,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
psa_status_t status = PSA_ERROR_GENERIC_ERROR;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->iv_required && !operation->iv_set) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
status = psa_driver_wrapper_cipher_finish(operation,
output,
output_size,
output_length);
exit:
if (status == PSA_SUCCESS) {
return psa_cipher_abort(operation);
} else {
*output_length = 0;
(void) psa_cipher_abort(operation);
return status;
}
}
psa_status_t psa_cipher_abort(psa_cipher_operation_t *operation)
{
if (operation->id == 0) {
/* The object has (apparently) been initialized but it is not (yet)
* in use. It's ok to call abort on such an object, and there's
* nothing to do. */
return PSA_SUCCESS;
}
psa_driver_wrapper_cipher_abort(operation);
operation->id = 0;
operation->iv_set = 0;
operation->iv_required = 0;
return PSA_SUCCESS;
}
psa_status_t psa_cipher_encrypt(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot = NULL;
uint8_t local_iv[PSA_CIPHER_IV_MAX_SIZE];
size_t default_iv_length = 0;
psa_key_attributes_t attributes;
if (!PSA_ALG_IS_CIPHER(alg)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
status = psa_get_and_lock_key_slot_with_policy(key, &slot,
PSA_KEY_USAGE_ENCRYPT,
alg);
if (status != PSA_SUCCESS) {
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
default_iv_length = PSA_CIPHER_IV_LENGTH(slot->attr.type, alg);
if (default_iv_length > PSA_CIPHER_IV_MAX_SIZE) {
status = PSA_ERROR_GENERIC_ERROR;
goto exit;
}
if (default_iv_length > 0) {
if (output_size < default_iv_length) {
status = PSA_ERROR_BUFFER_TOO_SMALL;
goto exit;
}
status = psa_generate_random(local_iv, default_iv_length);
if (status != PSA_SUCCESS) {
goto exit;
}
}
status = psa_driver_wrapper_cipher_encrypt(
&attributes, slot->key.data, slot->key.bytes,
alg, local_iv, default_iv_length, input, input_length,
psa_crypto_buffer_offset(output, default_iv_length),
output_size - default_iv_length, output_length);
exit:
unlock_status = psa_unregister_read_under_mutex(slot);
if (status == PSA_SUCCESS) {
status = unlock_status;
}
if (status == PSA_SUCCESS) {
if (default_iv_length > 0) {
memcpy(output, local_iv, default_iv_length);
}
*output_length += default_iv_length;
} else {
*output_length = 0;
}
return status;
}
psa_status_t psa_cipher_decrypt(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot = NULL;
psa_key_attributes_t attributes;
if (!PSA_ALG_IS_CIPHER(alg)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
status = psa_get_and_lock_key_slot_with_policy(key, &slot,
PSA_KEY_USAGE_DECRYPT,
alg);
if (status != PSA_SUCCESS) {
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
if (alg == PSA_ALG_CCM_STAR_NO_TAG &&
input_length < PSA_BLOCK_CIPHER_BLOCK_LENGTH(slot->attr.type)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
} else if (input_length < PSA_CIPHER_IV_LENGTH(slot->attr.type, alg)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
status = psa_driver_wrapper_cipher_decrypt(
&attributes, slot->key.data, slot->key.bytes,
alg, input, input_length,
output, output_size, output_length);
exit:
unlock_status = psa_unregister_read_under_mutex(slot);
if (status == PSA_SUCCESS) {
status = unlock_status;
}
if (status != PSA_SUCCESS) {
*output_length = 0;
}
return status;
}
/****************************************************************/
/* AEAD */
/****************************************************************/
/* Helper function to get the base algorithm from its variants. */
static psa_algorithm_t psa_aead_get_base_algorithm(psa_algorithm_t alg)
{
return PSA_ALG_AEAD_WITH_DEFAULT_LENGTH_TAG(alg);
}
/* Helper function to perform common nonce length checks. */
static psa_status_t psa_aead_check_nonce_length(psa_algorithm_t alg,
size_t nonce_length)
{
psa_algorithm_t base_alg = psa_aead_get_base_algorithm(alg);
switch (base_alg) {
#if defined(PSA_WANT_ALG_GCM)
case PSA_ALG_GCM:
/* Not checking max nonce size here as GCM spec allows almost
* arbitrarily large nonces. Please note that we do not generally
* recommend the usage of nonces of greater length than
* PSA_AEAD_NONCE_MAX_SIZE, as large nonces are hashed to a shorter
* size, which can then lead to collisions if you encrypt a very
* large number of messages.*/
if (nonce_length != 0) {
return PSA_SUCCESS;
}
break;
#endif /* PSA_WANT_ALG_GCM */
#if defined(PSA_WANT_ALG_CCM)
case PSA_ALG_CCM:
if (nonce_length >= 7 && nonce_length <= 13) {
return PSA_SUCCESS;
}
break;
#endif /* PSA_WANT_ALG_CCM */
#if defined(PSA_WANT_ALG_CHACHA20_POLY1305)
case PSA_ALG_CHACHA20_POLY1305:
if (nonce_length == 12) {
return PSA_SUCCESS;
} else if (nonce_length == 8) {
return PSA_ERROR_NOT_SUPPORTED;
}
break;
#endif /* PSA_WANT_ALG_CHACHA20_POLY1305 */
default:
(void) nonce_length;
return PSA_ERROR_NOT_SUPPORTED;
}
return PSA_ERROR_INVALID_ARGUMENT;
}
static psa_status_t psa_aead_check_algorithm(psa_algorithm_t alg)
{
if (!PSA_ALG_IS_AEAD(alg) || PSA_ALG_IS_WILDCARD(alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
return PSA_SUCCESS;
}
psa_status_t psa_aead_encrypt(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *nonce,
size_t nonce_length,
const uint8_t *additional_data,
size_t additional_data_length,
const uint8_t *plaintext,
size_t plaintext_length,
uint8_t *ciphertext,
size_t ciphertext_size,
size_t *ciphertext_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
*ciphertext_length = 0;
status = psa_aead_check_algorithm(alg);
if (status != PSA_SUCCESS) {
return status;
}
status = psa_get_and_lock_key_slot_with_policy(
key, &slot, PSA_KEY_USAGE_ENCRYPT, alg);
if (status != PSA_SUCCESS) {
return status;
}
psa_key_attributes_t attributes = {
.core = slot->attr
};
status = psa_aead_check_nonce_length(alg, nonce_length);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_driver_wrapper_aead_encrypt(
&attributes, slot->key.data, slot->key.bytes,
alg,
nonce, nonce_length,
additional_data, additional_data_length,
plaintext, plaintext_length,
ciphertext, ciphertext_size, ciphertext_length);
if (status != PSA_SUCCESS && ciphertext_size != 0) {
memset(ciphertext, 0, ciphertext_size);
}
exit:
psa_unregister_read_under_mutex(slot);
return status;
}
psa_status_t psa_aead_decrypt(mbedtls_svc_key_id_t key,
psa_algorithm_t alg,
const uint8_t *nonce,
size_t nonce_length,
const uint8_t *additional_data,
size_t additional_data_length,
const uint8_t *ciphertext,
size_t ciphertext_length,
uint8_t *plaintext,
size_t plaintext_size,
size_t *plaintext_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
*plaintext_length = 0;
status = psa_aead_check_algorithm(alg);
if (status != PSA_SUCCESS) {
return status;
}
status = psa_get_and_lock_key_slot_with_policy(
key, &slot, PSA_KEY_USAGE_DECRYPT, alg);
if (status != PSA_SUCCESS) {
return status;
}
psa_key_attributes_t attributes = {
.core = slot->attr
};
status = psa_aead_check_nonce_length(alg, nonce_length);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_driver_wrapper_aead_decrypt(
&attributes, slot->key.data, slot->key.bytes,
alg,
nonce, nonce_length,
additional_data, additional_data_length,
ciphertext, ciphertext_length,
plaintext, plaintext_size, plaintext_length);
if (status != PSA_SUCCESS && plaintext_size != 0) {
memset(plaintext, 0, plaintext_size);
}
exit:
psa_unregister_read_under_mutex(slot);
return status;
}
static psa_status_t psa_validate_tag_length(psa_algorithm_t alg)
{
const uint8_t tag_len = PSA_ALG_AEAD_GET_TAG_LENGTH(alg);
switch (PSA_ALG_AEAD_WITH_SHORTENED_TAG(alg, 0)) {
#if defined(PSA_WANT_ALG_CCM)
case PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_CCM, 0):
/* CCM allows the following tag lengths: 4, 6, 8, 10, 12, 14, 16.*/
if (tag_len < 4 || tag_len > 16 || tag_len % 2) {
return PSA_ERROR_INVALID_ARGUMENT;
}
break;
#endif /* PSA_WANT_ALG_CCM */
#if defined(PSA_WANT_ALG_GCM)
case PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_GCM, 0):
/* GCM allows the following tag lengths: 4, 8, 12, 13, 14, 15, 16. */
if (tag_len != 4 && tag_len != 8 && (tag_len < 12 || tag_len > 16)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
break;
#endif /* PSA_WANT_ALG_GCM */
#if defined(PSA_WANT_ALG_CHACHA20_POLY1305)
case PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_CHACHA20_POLY1305, 0):
/* We only support the default tag length. */
if (tag_len != 16) {
return PSA_ERROR_INVALID_ARGUMENT;
}
break;
#endif /* PSA_WANT_ALG_CHACHA20_POLY1305 */
default:
(void) tag_len;
return PSA_ERROR_NOT_SUPPORTED;
}
return PSA_SUCCESS;
}
/* Set the key for a multipart authenticated operation. */
static psa_status_t psa_aead_setup(psa_aead_operation_t *operation,
int is_encrypt,
mbedtls_svc_key_id_t key,
psa_algorithm_t alg)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot = NULL;
psa_key_usage_t key_usage = 0;
psa_key_attributes_t attributes;
status = psa_aead_check_algorithm(alg);
if (status != PSA_SUCCESS) {
goto exit;
}
if (operation->id != 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->nonce_set || operation->lengths_set ||
operation->ad_started || operation->body_started) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (is_encrypt) {
key_usage = PSA_KEY_USAGE_ENCRYPT;
} else {
key_usage = PSA_KEY_USAGE_DECRYPT;
}
status = psa_get_and_lock_key_slot_with_policy(key, &slot, key_usage,
alg);
if (status != PSA_SUCCESS) {
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
if ((status = psa_validate_tag_length(alg)) != PSA_SUCCESS) {
goto exit;
}
if (is_encrypt) {
status = psa_driver_wrapper_aead_encrypt_setup(operation,
&attributes,
slot->key.data,
slot->key.bytes,
alg);
} else {
status = psa_driver_wrapper_aead_decrypt_setup(operation,
&attributes,
slot->key.data,
slot->key.bytes,
alg);
}
if (status != PSA_SUCCESS) {
goto exit;
}
operation->key_type = psa_get_key_type(&attributes);
exit:
unlock_status = psa_unregister_read(slot);
if (status == PSA_SUCCESS) {
status = unlock_status;
operation->alg = psa_aead_get_base_algorithm(alg);
operation->is_encrypt = is_encrypt;
} else {
psa_aead_abort(operation);
}
return status;
}
/* Set the key for a multipart authenticated encryption operation. */
psa_status_t psa_aead_encrypt_setup(psa_aead_operation_t *operation,
mbedtls_svc_key_id_t key,
psa_algorithm_t alg)
{
return psa_aead_setup(operation, 1, key, alg);
}
/* Set the key for a multipart authenticated decryption operation. */
psa_status_t psa_aead_decrypt_setup(psa_aead_operation_t *operation,
mbedtls_svc_key_id_t key,
psa_algorithm_t alg)
{
return psa_aead_setup(operation, 0, key, alg);
}
/* Generate a random nonce / IV for multipart AEAD operation */
psa_status_t psa_aead_generate_nonce(psa_aead_operation_t *operation,
uint8_t *nonce,
size_t nonce_size,
size_t *nonce_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
uint8_t local_nonce[PSA_AEAD_NONCE_MAX_SIZE];
size_t required_nonce_size = 0;
*nonce_length = 0;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->nonce_set || !operation->is_encrypt) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
/* For CCM, this size may not be correct according to the PSA
* specification. The PSA Crypto 1.0.1 specification states:
*
* CCM encodes the plaintext length pLen in L octets, with L the smallest
* integer >= 2 where pLen < 2^(8L). The nonce length is then 15 - L bytes.
*
* However this restriction that L has to be the smallest integer is not
* applied in practice, and it is not implementable here since the
* plaintext length may or may not be known at this time. */
required_nonce_size = PSA_AEAD_NONCE_LENGTH(operation->key_type,
operation->alg);
if (nonce_size < required_nonce_size) {
status = PSA_ERROR_BUFFER_TOO_SMALL;
goto exit;
}
status = psa_generate_random(local_nonce, required_nonce_size);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_aead_set_nonce(operation, local_nonce, required_nonce_size);
exit:
if (status == PSA_SUCCESS) {
memcpy(nonce, local_nonce, required_nonce_size);
*nonce_length = required_nonce_size;
} else {
psa_aead_abort(operation);
}
return status;
}
/* Set the nonce for a multipart authenticated encryption or decryption
operation.*/
psa_status_t psa_aead_set_nonce(psa_aead_operation_t *operation,
const uint8_t *nonce,
size_t nonce_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->nonce_set) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
status = psa_aead_check_nonce_length(operation->alg, nonce_length);
if (status != PSA_SUCCESS) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
status = psa_driver_wrapper_aead_set_nonce(operation, nonce,
nonce_length);
exit:
if (status == PSA_SUCCESS) {
operation->nonce_set = 1;
} else {
psa_aead_abort(operation);
}
return status;
}
/* Declare the lengths of the message and additional data for multipart AEAD. */
psa_status_t psa_aead_set_lengths(psa_aead_operation_t *operation,
size_t ad_length,
size_t plaintext_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->lengths_set || operation->ad_started ||
operation->body_started) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
switch (operation->alg) {
#if defined(PSA_WANT_ALG_GCM)
case PSA_ALG_GCM:
/* Lengths can only be too large for GCM if size_t is bigger than 32
* bits. Without the guard this code will generate warnings on 32bit
* builds. */
#if SIZE_MAX > UINT32_MAX
if (((uint64_t) ad_length) >> 61 != 0 ||
((uint64_t) plaintext_length) > 0xFFFFFFFE0ull) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
#endif
break;
#endif /* PSA_WANT_ALG_GCM */
#if defined(PSA_WANT_ALG_CCM)
case PSA_ALG_CCM:
if (ad_length > 0xFF00) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
break;
#endif /* PSA_WANT_ALG_CCM */
#if defined(PSA_WANT_ALG_CHACHA20_POLY1305)
case PSA_ALG_CHACHA20_POLY1305:
/* No length restrictions for ChaChaPoly. */
break;
#endif /* PSA_WANT_ALG_CHACHA20_POLY1305 */
default:
break;
}
status = psa_driver_wrapper_aead_set_lengths(operation, ad_length,
plaintext_length);
exit:
if (status == PSA_SUCCESS) {
operation->ad_remaining = ad_length;
operation->body_remaining = plaintext_length;
operation->lengths_set = 1;
} else {
psa_aead_abort(operation);
}
return status;
}
/* Pass additional data to an active multipart AEAD operation. */
psa_status_t psa_aead_update_ad(psa_aead_operation_t *operation,
const uint8_t *input,
size_t input_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (!operation->nonce_set || operation->body_started) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->lengths_set) {
if (operation->ad_remaining < input_length) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
operation->ad_remaining -= input_length;
}
#if defined(PSA_WANT_ALG_CCM)
else if (operation->alg == PSA_ALG_CCM) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
#endif /* PSA_WANT_ALG_CCM */
status = psa_driver_wrapper_aead_update_ad(operation, input,
input_length);
exit:
if (status == PSA_SUCCESS) {
operation->ad_started = 1;
} else {
psa_aead_abort(operation);
}
return status;
}
/* Encrypt or decrypt a message fragment in an active multipart AEAD
operation.*/
psa_status_t psa_aead_update(psa_aead_operation_t *operation,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
*output_length = 0;
if (operation->id == 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (!operation->nonce_set) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (operation->lengths_set) {
/* Additional data length was supplied, but not all the additional
data was supplied.*/
if (operation->ad_remaining != 0) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
/* Too much data provided. */
if (operation->body_remaining < input_length) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
operation->body_remaining -= input_length;
}
#if defined(PSA_WANT_ALG_CCM)
else if (operation->alg == PSA_ALG_CCM) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
#endif /* PSA_WANT_ALG_CCM */
status = psa_driver_wrapper_aead_update(operation, input, input_length,
output, output_size,
output_length);
exit:
if (status == PSA_SUCCESS) {
operation->body_started = 1;
} else {
psa_aead_abort(operation);
}
return status;
}
static psa_status_t psa_aead_final_checks(const psa_aead_operation_t *operation)
{
if (operation->id == 0 || !operation->nonce_set) {
return PSA_ERROR_BAD_STATE;
}
if (operation->lengths_set && (operation->ad_remaining != 0 ||
operation->body_remaining != 0)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
return PSA_SUCCESS;
}
/* Finish encrypting a message in a multipart AEAD operation. */
psa_status_t psa_aead_finish(psa_aead_operation_t *operation,
uint8_t *ciphertext,
size_t ciphertext_size,
size_t *ciphertext_length,
uint8_t *tag,
size_t tag_size,
size_t *tag_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
*ciphertext_length = 0;
*tag_length = tag_size;
status = psa_aead_final_checks(operation);
if (status != PSA_SUCCESS) {
goto exit;
}
if (!operation->is_encrypt) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
status = psa_driver_wrapper_aead_finish(operation, ciphertext,
ciphertext_size,
ciphertext_length,
tag, tag_size, tag_length);
exit:
/* In case the operation fails and the user fails to check for failure or
* the zero tag size, make sure the tag is set to something implausible.
* Even if the operation succeeds, make sure we clear the rest of the
* buffer to prevent potential leakage of anything previously placed in
* the same buffer.*/
psa_wipe_tag_output_buffer(tag, status, tag_size, *tag_length);
psa_aead_abort(operation);
return status;
}
/* Finish authenticating and decrypting a message in a multipart AEAD
operation.*/
psa_status_t psa_aead_verify(psa_aead_operation_t *operation,
uint8_t *plaintext,
size_t plaintext_size,
size_t *plaintext_length,
const uint8_t *tag,
size_t tag_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
*plaintext_length = 0;
status = psa_aead_final_checks(operation);
if (status != PSA_SUCCESS) {
goto exit;
}
if (operation->is_encrypt) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
status = psa_driver_wrapper_aead_verify(operation, plaintext,
plaintext_size,
plaintext_length,
tag, tag_length);
exit:
psa_aead_abort(operation);
return status;
}
/* Abort an AEAD operation. */
psa_status_t psa_aead_abort(psa_aead_operation_t *operation)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->id == 0) {
/* The object has (apparently) been initialized but it is not (yet)
* in use. It's ok to call abort on such an object, and there's
* nothing to do. */
return PSA_SUCCESS;
}
status = psa_driver_wrapper_aead_abort(operation);
memset(operation, 0, sizeof(*operation));
return status;
}
/****************************************************************/
/* Generators */
/****************************************************************/
#if defined(BUILTIN_ALG_ANY_HKDF) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS) || \
defined(PSA_HAVE_SOFT_PBKDF2)
#define AT_LEAST_ONE_BUILTIN_KDF
#endif /* At least one builtin KDF */
#if defined(BUILTIN_ALG_ANY_HKDF) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
static psa_status_t psa_key_derivation_start_hmac(
psa_mac_operation_t *operation,
psa_algorithm_t hash_alg,
const uint8_t *hmac_key,
size_t hmac_key_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
psa_set_key_type(&attributes, PSA_KEY_TYPE_HMAC);
psa_set_key_bits(&attributes, PSA_BYTES_TO_BITS(hmac_key_length));
psa_set_key_usage_flags(&attributes, PSA_KEY_USAGE_SIGN_HASH);
operation->is_sign = 1;
operation->mac_size = PSA_HASH_LENGTH(hash_alg);
status = psa_driver_wrapper_mac_sign_setup(operation,
&attributes,
hmac_key, hmac_key_length,
PSA_ALG_HMAC(hash_alg));
psa_reset_key_attributes(&attributes);
return status;
}
#endif /* KDF algorithms reliant on HMAC */
#define HKDF_STATE_INIT 0 /* no input yet */
#define HKDF_STATE_STARTED 1 /* got salt */
#define HKDF_STATE_KEYED 2 /* got key */
#define HKDF_STATE_OUTPUT 3 /* output started */
static psa_algorithm_t psa_key_derivation_get_kdf_alg(
const psa_key_derivation_operation_t *operation)
{
if (PSA_ALG_IS_KEY_AGREEMENT(operation->alg)) {
return PSA_ALG_KEY_AGREEMENT_GET_KDF(operation->alg);
} else {
return operation->alg;
}
}
psa_status_t psa_key_derivation_abort(psa_key_derivation_operation_t *operation)
{
psa_status_t status = PSA_SUCCESS;
psa_algorithm_t kdf_alg = psa_key_derivation_get_kdf_alg(operation);
if (kdf_alg == 0) {
/* The object has (apparently) been initialized but it is not
* in use. It's ok to call abort on such an object, and there's
* nothing to do. */
} else
#if defined(BUILTIN_ALG_ANY_HKDF)
if (PSA_ALG_IS_ANY_HKDF(kdf_alg)) {
mbedtls_free(operation->ctx.hkdf.info);
status = psa_mac_abort(&operation->ctx.hkdf.hmac);
} else
#endif /* BUILTIN_ALG_ANY_HKDF */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
if (PSA_ALG_IS_TLS12_PRF(kdf_alg) ||
/* TLS-1.2 PSK-to-MS KDF uses the same core as TLS-1.2 PRF */
PSA_ALG_IS_TLS12_PSK_TO_MS(kdf_alg)) {
if (operation->ctx.tls12_prf.secret != NULL) {
mbedtls_zeroize_and_free(operation->ctx.tls12_prf.secret,
operation->ctx.tls12_prf.secret_length);
}
if (operation->ctx.tls12_prf.seed != NULL) {
mbedtls_zeroize_and_free(operation->ctx.tls12_prf.seed,
operation->ctx.tls12_prf.seed_length);
}
if (operation->ctx.tls12_prf.label != NULL) {
mbedtls_zeroize_and_free(operation->ctx.tls12_prf.label,
operation->ctx.tls12_prf.label_length);
}
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
if (operation->ctx.tls12_prf.other_secret != NULL) {
mbedtls_zeroize_and_free(operation->ctx.tls12_prf.other_secret,
operation->ctx.tls12_prf.other_secret_length);
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS */
status = PSA_SUCCESS;
/* We leave the fields Ai and output_block to be erased safely by the
* mbedtls_platform_zeroize() in the end of this function. */
} else
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) ||
* defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS) */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS)
if (kdf_alg == PSA_ALG_TLS12_ECJPAKE_TO_PMS) {
mbedtls_platform_zeroize(operation->ctx.tls12_ecjpake_to_pms.data,
sizeof(operation->ctx.tls12_ecjpake_to_pms.data));
} else
#endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS) */
#if defined(PSA_HAVE_SOFT_PBKDF2)
if (PSA_ALG_IS_PBKDF2(kdf_alg)) {
if (operation->ctx.pbkdf2.salt != NULL) {
mbedtls_zeroize_and_free(operation->ctx.pbkdf2.salt,
operation->ctx.pbkdf2.salt_length);
}
status = PSA_SUCCESS;
} else
#endif /* defined(PSA_HAVE_SOFT_PBKDF2) */
{
status = PSA_ERROR_BAD_STATE;
}
mbedtls_platform_zeroize(operation, sizeof(*operation));
return status;
}
psa_status_t psa_key_derivation_get_capacity(const psa_key_derivation_operation_t *operation,
size_t *capacity)
{
if (operation->alg == 0) {
/* This is a blank key derivation operation. */
return PSA_ERROR_BAD_STATE;
}
*capacity = operation->capacity;
return PSA_SUCCESS;
}
psa_status_t psa_key_derivation_set_capacity(psa_key_derivation_operation_t *operation,
size_t capacity)
{
if (operation->alg == 0) {
return PSA_ERROR_BAD_STATE;
}
if (capacity > operation->capacity) {
return PSA_ERROR_INVALID_ARGUMENT;
}
operation->capacity = capacity;
return PSA_SUCCESS;
}
#if defined(BUILTIN_ALG_ANY_HKDF)
/* Read some bytes from an HKDF-based operation. */
static psa_status_t psa_key_derivation_hkdf_read(psa_hkdf_key_derivation_t *hkdf,
psa_algorithm_t kdf_alg,
uint8_t *output,
size_t output_length)
{
psa_algorithm_t hash_alg = PSA_ALG_HKDF_GET_HASH(kdf_alg);
uint8_t hash_length = PSA_HASH_LENGTH(hash_alg);
size_t hmac_output_length;
psa_status_t status;
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT)
const uint8_t last_block = PSA_ALG_IS_HKDF_EXTRACT(kdf_alg) ? 0 : 0xff;
#else
const uint8_t last_block = 0xff;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT */
if (hkdf->state < HKDF_STATE_KEYED ||
(!hkdf->info_set
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT)
&& !PSA_ALG_IS_HKDF_EXTRACT(kdf_alg)
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT */
)) {
return PSA_ERROR_BAD_STATE;
}
hkdf->state = HKDF_STATE_OUTPUT;
while (output_length != 0) {
/* Copy what remains of the current block */
uint8_t n = hash_length - hkdf->offset_in_block;
if (n > output_length) {
n = (uint8_t) output_length;
}
memcpy(output, hkdf->output_block + hkdf->offset_in_block, n);
output += n;
output_length -= n;
hkdf->offset_in_block += n;
if (output_length == 0) {
break;
}
/* We can't be wanting more output after the last block, otherwise
* the capacity check in psa_key_derivation_output_bytes() would have
* prevented this call. It could happen only if the operation
* object was corrupted or if this function is called directly
* inside the library. */
if (hkdf->block_number == last_block) {
return PSA_ERROR_BAD_STATE;
}
/* We need a new block */
++hkdf->block_number;
hkdf->offset_in_block = 0;
status = psa_key_derivation_start_hmac(&hkdf->hmac,
hash_alg,
hkdf->prk,
hash_length);
if (status != PSA_SUCCESS) {
return status;
}
if (hkdf->block_number != 1) {
status = psa_mac_update(&hkdf->hmac,
hkdf->output_block,
hash_length);
if (status != PSA_SUCCESS) {
return status;
}
}
status = psa_mac_update(&hkdf->hmac,
hkdf->info,
hkdf->info_length);
if (status != PSA_SUCCESS) {
return status;
}
status = psa_mac_update(&hkdf->hmac,
&hkdf->block_number, 1);
if (status != PSA_SUCCESS) {
return status;
}
status = psa_mac_sign_finish(&hkdf->hmac,
hkdf->output_block,
sizeof(hkdf->output_block),
&hmac_output_length);
if (status != PSA_SUCCESS) {
return status;
}
}
return PSA_SUCCESS;
}
#endif /* BUILTIN_ALG_ANY_HKDF */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
static psa_status_t psa_key_derivation_tls12_prf_generate_next_block(
psa_tls12_prf_key_derivation_t *tls12_prf,
psa_algorithm_t alg)
{
psa_algorithm_t hash_alg = PSA_ALG_HKDF_GET_HASH(alg);
uint8_t hash_length = PSA_HASH_LENGTH(hash_alg);
psa_mac_operation_t hmac = PSA_MAC_OPERATION_INIT;
size_t hmac_output_length;
psa_status_t status, cleanup_status;
/* We can't be wanting more output after block 0xff, otherwise
* the capacity check in psa_key_derivation_output_bytes() would have
* prevented this call. It could happen only if the operation
* object was corrupted or if this function is called directly
* inside the library. */
if (tls12_prf->block_number == 0xff) {
return PSA_ERROR_CORRUPTION_DETECTED;
}
/* We need a new block */
++tls12_prf->block_number;
tls12_prf->left_in_block = hash_length;
/* Recall the definition of the TLS-1.2-PRF from RFC 5246:
*
* PRF(secret, label, seed) = P_<hash>(secret, label + seed)
*
* P_hash(secret, seed) = HMAC_hash(secret, A(1) + seed) +
* HMAC_hash(secret, A(2) + seed) +
* HMAC_hash(secret, A(3) + seed) + ...
*
* A(0) = seed
* A(i) = HMAC_hash(secret, A(i-1))
*
* The `psa_tls12_prf_key_derivation` structure saves the block
* `HMAC_hash(secret, A(i) + seed)` from which the output
* is currently extracted as `output_block` and where i is
* `block_number`.
*/
status = psa_key_derivation_start_hmac(&hmac,
hash_alg,
tls12_prf->secret,
tls12_prf->secret_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
/* Calculate A(i) where i = tls12_prf->block_number. */
if (tls12_prf->block_number == 1) {
/* A(1) = HMAC_hash(secret, A(0)), where A(0) = seed. (The RFC overloads
* the variable seed and in this instance means it in the context of the
* P_hash function, where seed = label + seed.) */
status = psa_mac_update(&hmac,
tls12_prf->label,
tls12_prf->label_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
status = psa_mac_update(&hmac,
tls12_prf->seed,
tls12_prf->seed_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
} else {
/* A(i) = HMAC_hash(secret, A(i-1)) */
status = psa_mac_update(&hmac, tls12_prf->Ai, hash_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
}
status = psa_mac_sign_finish(&hmac,
tls12_prf->Ai, hash_length,
&hmac_output_length);
if (hmac_output_length != hash_length) {
status = PSA_ERROR_CORRUPTION_DETECTED;
}
if (status != PSA_SUCCESS) {
goto cleanup;
}
/* Calculate HMAC_hash(secret, A(i) + label + seed). */
status = psa_key_derivation_start_hmac(&hmac,
hash_alg,
tls12_prf->secret,
tls12_prf->secret_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
status = psa_mac_update(&hmac, tls12_prf->Ai, hash_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
status = psa_mac_update(&hmac, tls12_prf->label, tls12_prf->label_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
status = psa_mac_update(&hmac, tls12_prf->seed, tls12_prf->seed_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
status = psa_mac_sign_finish(&hmac,
tls12_prf->output_block, hash_length,
&hmac_output_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
cleanup:
cleanup_status = psa_mac_abort(&hmac);
if (status == PSA_SUCCESS && cleanup_status != PSA_SUCCESS) {
status = cleanup_status;
}
return status;
}
static psa_status_t psa_key_derivation_tls12_prf_read(
psa_tls12_prf_key_derivation_t *tls12_prf,
psa_algorithm_t alg,
uint8_t *output,
size_t output_length)
{
psa_algorithm_t hash_alg = PSA_ALG_TLS12_PRF_GET_HASH(alg);
uint8_t hash_length = PSA_HASH_LENGTH(hash_alg);
psa_status_t status;
uint8_t offset, length;
switch (tls12_prf->state) {
case PSA_TLS12_PRF_STATE_LABEL_SET:
tls12_prf->state = PSA_TLS12_PRF_STATE_OUTPUT;
break;
case PSA_TLS12_PRF_STATE_OUTPUT:
break;
default:
return PSA_ERROR_BAD_STATE;
}
while (output_length != 0) {
/* Check if we have fully processed the current block. */
if (tls12_prf->left_in_block == 0) {
status = psa_key_derivation_tls12_prf_generate_next_block(tls12_prf,
alg);
if (status != PSA_SUCCESS) {
return status;
}
continue;
}
if (tls12_prf->left_in_block > output_length) {
length = (uint8_t) output_length;
} else {
length = tls12_prf->left_in_block;
}
offset = hash_length - tls12_prf->left_in_block;
memcpy(output, tls12_prf->output_block + offset, length);
output += length;
output_length -= length;
tls12_prf->left_in_block -= length;
}
return PSA_SUCCESS;
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF ||
* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS)
static psa_status_t psa_key_derivation_tls12_ecjpake_to_pms_read(
psa_tls12_ecjpake_to_pms_t *ecjpake,
uint8_t *output,
size_t output_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t output_size = 0;
if (output_length != 32) {
return PSA_ERROR_INVALID_ARGUMENT;
}
status = psa_hash_compute(PSA_ALG_SHA_256, ecjpake->data,
PSA_TLS12_ECJPAKE_TO_PMS_DATA_SIZE, output, output_length,
&output_size);
if (status != PSA_SUCCESS) {
return status;
}
if (output_size != output_length) {
return PSA_ERROR_GENERIC_ERROR;
}
return PSA_SUCCESS;
}
#endif
#if defined(PSA_HAVE_SOFT_PBKDF2)
static psa_status_t psa_key_derivation_pbkdf2_generate_block(
psa_pbkdf2_key_derivation_t *pbkdf2,
psa_algorithm_t prf_alg,
uint8_t prf_output_length,
psa_key_attributes_t *attributes)
{
psa_status_t status;
psa_mac_operation_t mac_operation = PSA_MAC_OPERATION_INIT;
size_t mac_output_length;
uint8_t U_i[PSA_MAC_MAX_SIZE];
uint8_t *U_accumulator = pbkdf2->output_block;
uint64_t i;
uint8_t block_counter[4];
mac_operation.is_sign = 1;
mac_operation.mac_size = prf_output_length;
MBEDTLS_PUT_UINT32_BE(pbkdf2->block_number, block_counter, 0);
status = psa_driver_wrapper_mac_sign_setup(&mac_operation,
attributes,
pbkdf2->password,
pbkdf2->password_length,
prf_alg);
if (status != PSA_SUCCESS) {
goto cleanup;
}
status = psa_mac_update(&mac_operation, pbkdf2->salt, pbkdf2->salt_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
status = psa_mac_update(&mac_operation, block_counter, sizeof(block_counter));
if (status != PSA_SUCCESS) {
goto cleanup;
}
status = psa_mac_sign_finish(&mac_operation, U_i, sizeof(U_i),
&mac_output_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
if (mac_output_length != prf_output_length) {
status = PSA_ERROR_CORRUPTION_DETECTED;
goto cleanup;
}
memcpy(U_accumulator, U_i, prf_output_length);
for (i = 1; i < pbkdf2->input_cost; i++) {
/* We are passing prf_output_length as mac_size because the driver
* function directly sets mac_output_length as mac_size upon success.
* See https://github.com/Mbed-TLS/mbedtls/issues/7801 */
status = psa_driver_wrapper_mac_compute(attributes,
pbkdf2->password,
pbkdf2->password_length,
prf_alg, U_i, prf_output_length,
U_i, prf_output_length,
&mac_output_length);
if (status != PSA_SUCCESS) {
goto cleanup;
}
mbedtls_xor(U_accumulator, U_accumulator, U_i, prf_output_length);
}
cleanup:
/* Zeroise buffers to clear sensitive data from memory. */
mbedtls_platform_zeroize(U_i, PSA_MAC_MAX_SIZE);
return status;
}
static psa_status_t psa_key_derivation_pbkdf2_read(
psa_pbkdf2_key_derivation_t *pbkdf2,
psa_algorithm_t kdf_alg,
uint8_t *output,
size_t output_length)
{
psa_status_t status;
psa_algorithm_t prf_alg;
uint8_t prf_output_length;
psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
psa_set_key_bits(&attributes, PSA_BYTES_TO_BITS(pbkdf2->password_length));
psa_set_key_usage_flags(&attributes, PSA_KEY_USAGE_SIGN_MESSAGE);
if (PSA_ALG_IS_PBKDF2_HMAC(kdf_alg)) {
prf_alg = PSA_ALG_HMAC(PSA_ALG_PBKDF2_HMAC_GET_HASH(kdf_alg));
prf_output_length = PSA_HASH_LENGTH(prf_alg);
psa_set_key_type(&attributes, PSA_KEY_TYPE_HMAC);
} else if (kdf_alg == PSA_ALG_PBKDF2_AES_CMAC_PRF_128) {
prf_alg = PSA_ALG_CMAC;
prf_output_length = PSA_MAC_LENGTH(PSA_KEY_TYPE_AES, 128U, PSA_ALG_CMAC);
psa_set_key_type(&attributes, PSA_KEY_TYPE_AES);
} else {
return PSA_ERROR_INVALID_ARGUMENT;
}
switch (pbkdf2->state) {
case PSA_PBKDF2_STATE_PASSWORD_SET:
/* Initially we need a new block so bytes_used is equal to block size*/
pbkdf2->bytes_used = prf_output_length;
pbkdf2->state = PSA_PBKDF2_STATE_OUTPUT;
break;
case PSA_PBKDF2_STATE_OUTPUT:
break;
default:
return PSA_ERROR_BAD_STATE;
}
while (output_length != 0) {
uint8_t n = prf_output_length - pbkdf2->bytes_used;
if (n > output_length) {
n = (uint8_t) output_length;
}
memcpy(output, pbkdf2->output_block + pbkdf2->bytes_used, n);
output += n;
output_length -= n;
pbkdf2->bytes_used += n;
if (output_length == 0) {
break;
}
/* We need a new block */
pbkdf2->bytes_used = 0;
pbkdf2->block_number++;
status = psa_key_derivation_pbkdf2_generate_block(pbkdf2, prf_alg,
prf_output_length,
&attributes);
if (status != PSA_SUCCESS) {
return status;
}
}
return PSA_SUCCESS;
}
#endif /* PSA_HAVE_SOFT_PBKDF2 */
psa_status_t psa_key_derivation_output_bytes(
psa_key_derivation_operation_t *operation,
uint8_t *output,
size_t output_length)
{
psa_status_t status;
psa_algorithm_t kdf_alg = psa_key_derivation_get_kdf_alg(operation);
if (operation->alg == 0) {
/* This is a blank operation. */
return PSA_ERROR_BAD_STATE;
}
if (output_length > operation->capacity) {
operation->capacity = 0;
/* Go through the error path to wipe all confidential data now
* that the operation object is useless. */
status = PSA_ERROR_INSUFFICIENT_DATA;
goto exit;
}
if (output_length == 0 && operation->capacity == 0) {
/* Edge case: this is a finished operation, and 0 bytes
* were requested. The right error in this case could
* be either INSUFFICIENT_CAPACITY or BAD_STATE. Return
* INSUFFICIENT_CAPACITY, which is right for a finished
* operation, for consistency with the case when
* output_length > 0. */
return PSA_ERROR_INSUFFICIENT_DATA;
}
operation->capacity -= output_length;
#if defined(BUILTIN_ALG_ANY_HKDF)
if (PSA_ALG_IS_ANY_HKDF(kdf_alg)) {
status = psa_key_derivation_hkdf_read(&operation->ctx.hkdf, kdf_alg,
output, output_length);
} else
#endif /* BUILTIN_ALG_ANY_HKDF */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
if (PSA_ALG_IS_TLS12_PRF(kdf_alg) ||
PSA_ALG_IS_TLS12_PSK_TO_MS(kdf_alg)) {
status = psa_key_derivation_tls12_prf_read(&operation->ctx.tls12_prf,
kdf_alg, output,
output_length);
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF ||
* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS)
if (kdf_alg == PSA_ALG_TLS12_ECJPAKE_TO_PMS) {
status = psa_key_derivation_tls12_ecjpake_to_pms_read(
&operation->ctx.tls12_ecjpake_to_pms, output, output_length);
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS */
#if defined(PSA_HAVE_SOFT_PBKDF2)
if (PSA_ALG_IS_PBKDF2(kdf_alg)) {
status = psa_key_derivation_pbkdf2_read(&operation->ctx.pbkdf2, kdf_alg,
output, output_length);
} else
#endif /* PSA_HAVE_SOFT_PBKDF2 */
{
(void) kdf_alg;
return PSA_ERROR_BAD_STATE;
}
exit:
if (status != PSA_SUCCESS) {
/* Preserve the algorithm upon errors, but clear all sensitive state.
* This allows us to differentiate between exhausted operations and
* blank operations, so we can return PSA_ERROR_BAD_STATE on blank
* operations. */
psa_algorithm_t alg = operation->alg;
psa_key_derivation_abort(operation);
operation->alg = alg;
memset(output, '!', output_length);
}
return status;
}
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES)
static void psa_des_set_key_parity(uint8_t *data, size_t data_size)
{
if (data_size >= 8) {
mbedtls_des_key_set_parity(data);
}
if (data_size >= 16) {
mbedtls_des_key_set_parity(data + 8);
}
if (data_size >= 24) {
mbedtls_des_key_set_parity(data + 16);
}
}
#endif /* MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES */
/*
* ECC keys on a Weierstrass elliptic curve require the generation
* of a private key which is an integer
* in the range [1, N - 1], where N is the boundary of the private key domain:
* N is the prime p for Diffie-Hellman, or the order of the
* curve’s base point for ECC.
*
* Let m be the bit size of N, such that 2^m > N >= 2^(m-1).
* This function generates the private key using the following process:
*
* 1. Draw a byte string of length ceiling(m/8) bytes.
* 2. If m is not a multiple of 8, set the most significant
* (8 * ceiling(m/8) - m) bits of the first byte in the string to zero.
* 3. Convert the string to integer k by decoding it as a big-endian byte string.
* 4. If k > N - 2, discard the result and return to step 1.
* 5. Output k + 1 as the private key.
*
* This method allows compliance to NIST standards, specifically the methods titled
* Key-Pair Generation by Testing Candidates in the following publications:
* - NIST Special Publication 800-56A: Recommendation for Pair-Wise Key-Establishment
* Schemes Using Discrete Logarithm Cryptography [SP800-56A] §5.6.1.1.4 for
* Diffie-Hellman keys.
*
* - [SP800-56A] §5.6.1.2.2 or FIPS Publication 186-4: Digital Signature
* Standard (DSS) [FIPS186-4] §B.4.2 for elliptic curve keys.
*
* Note: Function allocates memory for *data buffer, so given *data should be
* always NULL.
*/
#if defined(PSA_WANT_KEY_TYPE_ECC_KEY_PAIR_DERIVE)
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_DERIVE)
static psa_status_t psa_generate_derived_ecc_key_weierstrass_helper(
psa_key_slot_t *slot,
size_t bits,
psa_key_derivation_operation_t *operation,
uint8_t **data
)
{
unsigned key_out_of_range = 1;
mbedtls_mpi k;
mbedtls_mpi diff_N_2;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t m;
size_t m_bytes;
mbedtls_mpi_init(&k);
mbedtls_mpi_init(&diff_N_2);
psa_ecc_family_t curve = PSA_KEY_TYPE_ECC_GET_FAMILY(
slot->attr.type);
mbedtls_ecp_group_id grp_id =
mbedtls_ecc_group_from_psa(curve, bits);
if (grp_id == MBEDTLS_ECP_DP_NONE) {
ret = MBEDTLS_ERR_ASN1_INVALID_DATA;
goto cleanup;
}
mbedtls_ecp_group ecp_group;
mbedtls_ecp_group_init(&ecp_group);
MBEDTLS_MPI_CHK(mbedtls_ecp_group_load(&ecp_group, grp_id));
/* N is the boundary of the private key domain (ecp_group.N). */
/* Let m be the bit size of N. */
m = ecp_group.nbits;
m_bytes = PSA_BITS_TO_BYTES(m);
/* Calculate N - 2 - it will be needed later. */
MBEDTLS_MPI_CHK(mbedtls_mpi_sub_int(&diff_N_2, &ecp_group.N, 2));
/* Note: This function is always called with *data == NULL and it
* allocates memory for the data buffer. */
*data = mbedtls_calloc(1, m_bytes);
if (*data == NULL) {
ret = MBEDTLS_ERR_ASN1_ALLOC_FAILED;
goto cleanup;
}
while (key_out_of_range) {
/* 1. Draw a byte string of length ceiling(m/8) bytes. */
if ((status = psa_key_derivation_output_bytes(operation, *data, m_bytes)) != 0) {
goto cleanup;
}
/* 2. If m is not a multiple of 8 */
if (m % 8 != 0) {
/* Set the most significant
* (8 * ceiling(m/8) - m) bits of the first byte in
* the string to zero.
*/
uint8_t clear_bit_mask = (1 << (m % 8)) - 1;
(*data)[0] &= clear_bit_mask;
}
/* 3. Convert the string to integer k by decoding it as a
* big-endian byte string.
*/
MBEDTLS_MPI_CHK(mbedtls_mpi_read_binary(&k, *data, m_bytes));
/* 4. If k > N - 2, discard the result and return to step 1.
* Result of comparison is returned. When it indicates error
* then this function is called again.
*/
MBEDTLS_MPI_CHK(mbedtls_mpi_lt_mpi_ct(&diff_N_2, &k, &key_out_of_range));
}
/* 5. Output k + 1 as the private key. */
MBEDTLS_MPI_CHK(mbedtls_mpi_add_int(&k, &k, 1));
MBEDTLS_MPI_CHK(mbedtls_mpi_write_binary(&k, *data, m_bytes));
cleanup:
if (ret != 0) {
status = mbedtls_to_psa_error(ret);
}
if (status != PSA_SUCCESS) {
mbedtls_free(*data);
*data = NULL;
}
mbedtls_mpi_free(&k);
mbedtls_mpi_free(&diff_N_2);
return status;
}
/* ECC keys on a Montgomery elliptic curve draws a byte string whose length
* is determined by the curve, and sets the mandatory bits accordingly. That is:
*
* - Curve25519 (PSA_ECC_FAMILY_MONTGOMERY, 255 bits):
* draw a 32-byte string and process it as specified in
* Elliptic Curves for Security [RFC7748] §5.
*
* - Curve448 (PSA_ECC_FAMILY_MONTGOMERY, 448 bits):
* draw a 56-byte string and process it as specified in [RFC7748] §5.
*
* Note: Function allocates memory for *data buffer, so given *data should be
* always NULL.
*/
static psa_status_t psa_generate_derived_ecc_key_montgomery_helper(
size_t bits,
psa_key_derivation_operation_t *operation,
uint8_t **data
)
{
size_t output_length;
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
switch (bits) {
case 255:
output_length = 32;
break;
case 448:
output_length = 56;
break;
default:
return PSA_ERROR_INVALID_ARGUMENT;
break;
}
*data = mbedtls_calloc(1, output_length);
if (*data == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
status = psa_key_derivation_output_bytes(operation, *data, output_length);
if (status != PSA_SUCCESS) {
return status;
}
switch (bits) {
case 255:
(*data)[0] &= 248;
(*data)[31] &= 127;
(*data)[31] |= 64;
break;
case 448:
(*data)[0] &= 252;
(*data)[55] |= 128;
break;
default:
return PSA_ERROR_CORRUPTION_DETECTED;
break;
}
return status;
}
#else /* MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_DERIVE */
static psa_status_t psa_generate_derived_ecc_key_weierstrass_helper(
psa_key_slot_t *slot, size_t bits,
psa_key_derivation_operation_t *operation, uint8_t **data)
{
(void) slot;
(void) bits;
(void) operation;
(void) data;
return PSA_ERROR_NOT_SUPPORTED;
}
static psa_status_t psa_generate_derived_ecc_key_montgomery_helper(
size_t bits, psa_key_derivation_operation_t *operation, uint8_t **data)
{
(void) bits;
(void) operation;
(void) data;
return PSA_ERROR_NOT_SUPPORTED;
}
#endif /* MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_DERIVE */
#endif /* PSA_WANT_KEY_TYPE_ECC_KEY_PAIR_DERIVE */
static psa_status_t psa_generate_derived_key_internal(
psa_key_slot_t *slot,
size_t bits,
psa_key_derivation_operation_t *operation)
{
uint8_t *data = NULL;
size_t bytes = PSA_BITS_TO_BYTES(bits);
size_t storage_size = bytes;
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_attributes_t attributes;
if (PSA_KEY_TYPE_IS_PUBLIC_KEY(slot->attr.type)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
#if defined(PSA_WANT_KEY_TYPE_ECC_KEY_PAIR_DERIVE) || \
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_DERIVE)
if (PSA_KEY_TYPE_IS_ECC(slot->attr.type)) {
psa_ecc_family_t curve = PSA_KEY_TYPE_ECC_GET_FAMILY(slot->attr.type);
if (PSA_ECC_FAMILY_IS_WEIERSTRASS(curve)) {
/* Weierstrass elliptic curve */
status = psa_generate_derived_ecc_key_weierstrass_helper(slot, bits, operation, &data);
if (status != PSA_SUCCESS) {
goto exit;
}
} else {
/* Montgomery elliptic curve */
status = psa_generate_derived_ecc_key_montgomery_helper(bits, operation, &data);
if (status != PSA_SUCCESS) {
goto exit;
}
}
} else
#endif /* defined(PSA_WANT_KEY_TYPE_ECC_KEY_PAIR_DERIVE) ||
defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_DERIVE) */
if (key_type_is_raw_bytes(slot->attr.type)) {
if (bits % 8 != 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
data = mbedtls_calloc(1, bytes);
if (data == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
status = psa_key_derivation_output_bytes(operation, data, bytes);
if (status != PSA_SUCCESS) {
goto exit;
}
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES)
if (slot->attr.type == PSA_KEY_TYPE_DES) {
psa_des_set_key_parity(data, bytes);
}
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES) */
} else {
return PSA_ERROR_NOT_SUPPORTED;
}
slot->attr.bits = (psa_key_bits_t) bits;
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
if (psa_key_lifetime_is_external(attributes.core.lifetime)) {
status = psa_driver_wrapper_get_key_buffer_size(&attributes,
&storage_size);
if (status != PSA_SUCCESS) {
goto exit;
}
}
status = psa_allocate_buffer_to_slot(slot, storage_size);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_driver_wrapper_import_key(&attributes,
data, bytes,
slot->key.data,
slot->key.bytes,
&slot->key.bytes, &bits);
if (bits != slot->attr.bits) {
status = PSA_ERROR_INVALID_ARGUMENT;
}
exit:
mbedtls_free(data);
return status;
}
psa_status_t psa_key_derivation_output_key(const psa_key_attributes_t *attributes,
psa_key_derivation_operation_t *operation,
mbedtls_svc_key_id_t *key)
{
psa_status_t status;
psa_key_slot_t *slot = NULL;
psa_se_drv_table_entry_t *driver = NULL;
*key = MBEDTLS_SVC_KEY_ID_INIT;
/* Reject any attempt to create a zero-length key so that we don't
* risk tripping up later, e.g. on a malloc(0) that returns NULL. */
if (psa_get_key_bits(attributes) == 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
if (operation->alg == PSA_ALG_NONE) {
return PSA_ERROR_BAD_STATE;
}
if (!operation->can_output_key) {
return PSA_ERROR_NOT_PERMITTED;
}
status = psa_start_key_creation(PSA_KEY_CREATION_DERIVE, attributes,
&slot, &driver);
#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
if (driver != NULL) {
/* Deriving a key in a secure element is not implemented yet. */
status = PSA_ERROR_NOT_SUPPORTED;
}
#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
if (status == PSA_SUCCESS) {
status = psa_generate_derived_key_internal(slot,
attributes->core.bits,
operation);
}
if (status == PSA_SUCCESS) {
status = psa_finish_key_creation(slot, driver, key);
}
if (status != PSA_SUCCESS) {
psa_fail_key_creation(slot, driver);
}
return status;
}
/****************************************************************/
/* Key derivation */
/****************************************************************/
#if defined(AT_LEAST_ONE_BUILTIN_KDF)
static int is_kdf_alg_supported(psa_algorithm_t kdf_alg)
{
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF)
if (PSA_ALG_IS_HKDF(kdf_alg)) {
return 1;
}
#endif
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT)
if (PSA_ALG_IS_HKDF_EXTRACT(kdf_alg)) {
return 1;
}
#endif
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXPAND)
if (PSA_ALG_IS_HKDF_EXPAND(kdf_alg)) {
return 1;
}
#endif
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF)
if (PSA_ALG_IS_TLS12_PRF(kdf_alg)) {
return 1;
}
#endif
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
if (PSA_ALG_IS_TLS12_PSK_TO_MS(kdf_alg)) {
return 1;
}
#endif
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS)
if (kdf_alg == PSA_ALG_TLS12_ECJPAKE_TO_PMS) {
return 1;
}
#endif
#if defined(MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_HMAC)
if (PSA_ALG_IS_PBKDF2_HMAC(kdf_alg)) {
return 1;
}
#endif
#if defined(MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_AES_CMAC_PRF_128)
if (kdf_alg == PSA_ALG_PBKDF2_AES_CMAC_PRF_128) {
return 1;
}
#endif
return 0;
}
static psa_status_t psa_hash_try_support(psa_algorithm_t alg)
{
psa_hash_operation_t operation = PSA_HASH_OPERATION_INIT;
psa_status_t status = psa_hash_setup(&operation, alg);
psa_hash_abort(&operation);
return status;
}
static psa_status_t psa_key_derivation_setup_kdf(
psa_key_derivation_operation_t *operation,
psa_algorithm_t kdf_alg)
{
/* Make sure that operation->ctx is properly zero-initialised. (Macro
* initialisers for this union leave some bytes unspecified.) */
memset(&operation->ctx, 0, sizeof(operation->ctx));
/* Make sure that kdf_alg is a supported key derivation algorithm. */
if (!is_kdf_alg_supported(kdf_alg)) {
return PSA_ERROR_NOT_SUPPORTED;
}
/* All currently supported key derivation algorithms (apart from
* ecjpake to pms and pbkdf2_aes_cmac_128) are based on a hash algorithm. */
psa_algorithm_t hash_alg = PSA_ALG_HKDF_GET_HASH(kdf_alg);
size_t hash_size = PSA_HASH_LENGTH(hash_alg);
if (kdf_alg == PSA_ALG_TLS12_ECJPAKE_TO_PMS) {
hash_size = PSA_HASH_LENGTH(PSA_ALG_SHA_256);
} else if (kdf_alg == PSA_ALG_PBKDF2_AES_CMAC_PRF_128) {
hash_size = PSA_MAC_LENGTH(PSA_KEY_TYPE_AES, 128U, PSA_ALG_CMAC);
} else {
if (hash_size == 0) {
return PSA_ERROR_NOT_SUPPORTED;
}
/* Make sure that hash_alg is a supported hash algorithm. Otherwise
* we might fail later, which is somewhat unfriendly and potentially
* risk-prone. */
psa_status_t status = psa_hash_try_support(hash_alg);
if (status != PSA_SUCCESS) {
return status;
}
}
if ((PSA_ALG_IS_TLS12_PRF(kdf_alg) ||
PSA_ALG_IS_TLS12_PSK_TO_MS(kdf_alg)) &&
!(hash_alg == PSA_ALG_SHA_256 || hash_alg == PSA_ALG_SHA_384)) {
return PSA_ERROR_NOT_SUPPORTED;
}
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS)
if (PSA_ALG_IS_HKDF_EXTRACT(kdf_alg) ||
(kdf_alg == PSA_ALG_TLS12_ECJPAKE_TO_PMS)) {
operation->capacity = hash_size;
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT ||
MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS */
operation->capacity = 255 * hash_size;
return PSA_SUCCESS;
}
static psa_status_t psa_key_agreement_try_support(psa_algorithm_t alg)
{
#if defined(PSA_WANT_ALG_ECDH)
if (alg == PSA_ALG_ECDH) {
return PSA_SUCCESS;
}
#endif
#if defined(PSA_WANT_ALG_FFDH)
if (alg == PSA_ALG_FFDH) {
return PSA_SUCCESS;
}
#endif
(void) alg;
return PSA_ERROR_NOT_SUPPORTED;
}
static int psa_key_derivation_allows_free_form_secret_input(
psa_algorithm_t kdf_alg)
{
#if defined(PSA_WANT_ALG_TLS12_ECJPAKE_TO_PMS)
if (kdf_alg == PSA_ALG_TLS12_ECJPAKE_TO_PMS) {
return 0;
}
#endif
(void) kdf_alg;
return 1;
}
#endif /* AT_LEAST_ONE_BUILTIN_KDF */
psa_status_t psa_key_derivation_setup(psa_key_derivation_operation_t *operation,
psa_algorithm_t alg)
{
psa_status_t status;
if (operation->alg != 0) {
return PSA_ERROR_BAD_STATE;
}
if (PSA_ALG_IS_RAW_KEY_AGREEMENT(alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
} else if (PSA_ALG_IS_KEY_AGREEMENT(alg)) {
#if defined(AT_LEAST_ONE_BUILTIN_KDF)
psa_algorithm_t kdf_alg = PSA_ALG_KEY_AGREEMENT_GET_KDF(alg);
psa_algorithm_t ka_alg = PSA_ALG_KEY_AGREEMENT_GET_BASE(alg);
status = psa_key_agreement_try_support(ka_alg);
if (status != PSA_SUCCESS) {
return status;
}
if (!psa_key_derivation_allows_free_form_secret_input(kdf_alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
status = psa_key_derivation_setup_kdf(operation, kdf_alg);
#else
return PSA_ERROR_NOT_SUPPORTED;
#endif /* AT_LEAST_ONE_BUILTIN_KDF */
} else if (PSA_ALG_IS_KEY_DERIVATION(alg)) {
#if defined(AT_LEAST_ONE_BUILTIN_KDF)
status = psa_key_derivation_setup_kdf(operation, alg);
#else
return PSA_ERROR_NOT_SUPPORTED;
#endif /* AT_LEAST_ONE_BUILTIN_KDF */
} else {
return PSA_ERROR_INVALID_ARGUMENT;
}
if (status == PSA_SUCCESS) {
operation->alg = alg;
}
return status;
}
#if defined(BUILTIN_ALG_ANY_HKDF)
static psa_status_t psa_hkdf_input(psa_hkdf_key_derivation_t *hkdf,
psa_algorithm_t kdf_alg,
psa_key_derivation_step_t step,
const uint8_t *data,
size_t data_length)
{
psa_algorithm_t hash_alg = PSA_ALG_HKDF_GET_HASH(kdf_alg);
psa_status_t status;
switch (step) {
case PSA_KEY_DERIVATION_INPUT_SALT:
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXPAND)
if (PSA_ALG_IS_HKDF_EXPAND(kdf_alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXPAND */
if (hkdf->state != HKDF_STATE_INIT) {
return PSA_ERROR_BAD_STATE;
} else {
status = psa_key_derivation_start_hmac(&hkdf->hmac,
hash_alg,
data, data_length);
if (status != PSA_SUCCESS) {
return status;
}
hkdf->state = HKDF_STATE_STARTED;
return PSA_SUCCESS;
}
case PSA_KEY_DERIVATION_INPUT_SECRET:
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXPAND)
if (PSA_ALG_IS_HKDF_EXPAND(kdf_alg)) {
/* We shouldn't be in different state as HKDF_EXPAND only allows
* two inputs: SECRET (this case) and INFO which does not modify
* the state. It could happen only if the hkdf
* object was corrupted. */
if (hkdf->state != HKDF_STATE_INIT) {
return PSA_ERROR_BAD_STATE;
}
/* Allow only input that fits expected prk size */
if (data_length != PSA_HASH_LENGTH(hash_alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
memcpy(hkdf->prk, data, data_length);
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXPAND */
{
/* HKDF: If no salt was provided, use an empty salt.
* HKDF-EXTRACT: salt is mandatory. */
if (hkdf->state == HKDF_STATE_INIT) {
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT)
if (PSA_ALG_IS_HKDF_EXTRACT(kdf_alg)) {
return PSA_ERROR_BAD_STATE;
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT */
status = psa_key_derivation_start_hmac(&hkdf->hmac,
hash_alg,
NULL, 0);
if (status != PSA_SUCCESS) {
return status;
}
hkdf->state = HKDF_STATE_STARTED;
}
if (hkdf->state != HKDF_STATE_STARTED) {
return PSA_ERROR_BAD_STATE;
}
status = psa_mac_update(&hkdf->hmac,
data, data_length);
if (status != PSA_SUCCESS) {
return status;
}
status = psa_mac_sign_finish(&hkdf->hmac,
hkdf->prk,
sizeof(hkdf->prk),
&data_length);
if (status != PSA_SUCCESS) {
return status;
}
}
hkdf->state = HKDF_STATE_KEYED;
hkdf->block_number = 0;
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT)
if (PSA_ALG_IS_HKDF_EXTRACT(kdf_alg)) {
/* The only block of output is the PRK. */
memcpy(hkdf->output_block, hkdf->prk, PSA_HASH_LENGTH(hash_alg));
hkdf->offset_in_block = 0;
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT */
{
/* Block 0 is empty, and the next block will be
* generated by psa_key_derivation_hkdf_read(). */
hkdf->offset_in_block = PSA_HASH_LENGTH(hash_alg);
}
return PSA_SUCCESS;
case PSA_KEY_DERIVATION_INPUT_INFO:
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT)
if (PSA_ALG_IS_HKDF_EXTRACT(kdf_alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXPAND)
if (PSA_ALG_IS_HKDF_EXPAND(kdf_alg) &&
hkdf->state == HKDF_STATE_INIT) {
return PSA_ERROR_BAD_STATE;
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HKDF_EXTRACT */
if (hkdf->state == HKDF_STATE_OUTPUT) {
return PSA_ERROR_BAD_STATE;
}
if (hkdf->info_set) {
return PSA_ERROR_BAD_STATE;
}
hkdf->info_length = data_length;
if (data_length != 0) {
hkdf->info = mbedtls_calloc(1, data_length);
if (hkdf->info == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
memcpy(hkdf->info, data, data_length);
}
hkdf->info_set = 1;
return PSA_SUCCESS;
default:
return PSA_ERROR_INVALID_ARGUMENT;
}
}
#endif /* BUILTIN_ALG_ANY_HKDF */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
static psa_status_t psa_tls12_prf_set_seed(psa_tls12_prf_key_derivation_t *prf,
const uint8_t *data,
size_t data_length)
{
if (prf->state != PSA_TLS12_PRF_STATE_INIT) {
return PSA_ERROR_BAD_STATE;
}
if (data_length != 0) {
prf->seed = mbedtls_calloc(1, data_length);
if (prf->seed == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
memcpy(prf->seed, data, data_length);
prf->seed_length = data_length;
}
prf->state = PSA_TLS12_PRF_STATE_SEED_SET;
return PSA_SUCCESS;
}
static psa_status_t psa_tls12_prf_set_key(psa_tls12_prf_key_derivation_t *prf,
const uint8_t *data,
size_t data_length)
{
if (prf->state != PSA_TLS12_PRF_STATE_SEED_SET &&
prf->state != PSA_TLS12_PRF_STATE_OTHER_KEY_SET) {
return PSA_ERROR_BAD_STATE;
}
if (data_length != 0) {
prf->secret = mbedtls_calloc(1, data_length);
if (prf->secret == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
memcpy(prf->secret, data, data_length);
prf->secret_length = data_length;
}
prf->state = PSA_TLS12_PRF_STATE_KEY_SET;
return PSA_SUCCESS;
}
static psa_status_t psa_tls12_prf_set_label(psa_tls12_prf_key_derivation_t *prf,
const uint8_t *data,
size_t data_length)
{
if (prf->state != PSA_TLS12_PRF_STATE_KEY_SET) {
return PSA_ERROR_BAD_STATE;
}
if (data_length != 0) {
prf->label = mbedtls_calloc(1, data_length);
if (prf->label == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
memcpy(prf->label, data, data_length);
prf->label_length = data_length;
}
prf->state = PSA_TLS12_PRF_STATE_LABEL_SET;
return PSA_SUCCESS;
}
static psa_status_t psa_tls12_prf_input(psa_tls12_prf_key_derivation_t *prf,
psa_key_derivation_step_t step,
const uint8_t *data,
size_t data_length)
{
switch (step) {
case PSA_KEY_DERIVATION_INPUT_SEED:
return psa_tls12_prf_set_seed(prf, data, data_length);
case PSA_KEY_DERIVATION_INPUT_SECRET:
return psa_tls12_prf_set_key(prf, data, data_length);
case PSA_KEY_DERIVATION_INPUT_LABEL:
return psa_tls12_prf_set_label(prf, data, data_length);
default:
return PSA_ERROR_INVALID_ARGUMENT;
}
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) ||
* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
static psa_status_t psa_tls12_prf_psk_to_ms_set_key(
psa_tls12_prf_key_derivation_t *prf,
const uint8_t *data,
size_t data_length)
{
psa_status_t status;
const size_t pms_len = (prf->state == PSA_TLS12_PRF_STATE_OTHER_KEY_SET ?
4 + data_length + prf->other_secret_length :
4 + 2 * data_length);
if (data_length > PSA_TLS12_PSK_TO_MS_PSK_MAX_SIZE) {
return PSA_ERROR_INVALID_ARGUMENT;
}
uint8_t *pms = mbedtls_calloc(1, pms_len);
if (pms == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
uint8_t *cur = pms;
/* pure-PSK:
* Quoting RFC 4279, Section 2:
*
* The premaster secret is formed as follows: if the PSK is N octets
* long, concatenate a uint16 with the value N, N zero octets, a second
* uint16 with the value N, and the PSK itself.
*
* mixed-PSK:
* In a DHE-PSK, RSA-PSK, ECDHE-PSK the premaster secret is formed as
* follows: concatenate a uint16 with the length of the other secret,
* the other secret itself, uint16 with the length of PSK, and the
* PSK itself.
* For details please check:
* - RFC 4279, Section 4 for the definition of RSA-PSK,
* - RFC 4279, Section 3 for the definition of DHE-PSK,
* - RFC 5489 for the definition of ECDHE-PSK.
*/
if (prf->state == PSA_TLS12_PRF_STATE_OTHER_KEY_SET) {
*cur++ = MBEDTLS_BYTE_1(prf->other_secret_length);
*cur++ = MBEDTLS_BYTE_0(prf->other_secret_length);
if (prf->other_secret_length != 0) {
memcpy(cur, prf->other_secret, prf->other_secret_length);
mbedtls_platform_zeroize(prf->other_secret, prf->other_secret_length);
cur += prf->other_secret_length;
}
} else {
*cur++ = MBEDTLS_BYTE_1(data_length);
*cur++ = MBEDTLS_BYTE_0(data_length);
memset(cur, 0, data_length);
cur += data_length;
}
*cur++ = MBEDTLS_BYTE_1(data_length);
*cur++ = MBEDTLS_BYTE_0(data_length);
memcpy(cur, data, data_length);
cur += data_length;
status = psa_tls12_prf_set_key(prf, pms, (size_t) (cur - pms));
mbedtls_zeroize_and_free(pms, pms_len);
return status;
}
static psa_status_t psa_tls12_prf_psk_to_ms_set_other_key(
psa_tls12_prf_key_derivation_t *prf,
const uint8_t *data,
size_t data_length)
{
if (prf->state != PSA_TLS12_PRF_STATE_SEED_SET) {
return PSA_ERROR_BAD_STATE;
}
if (data_length != 0) {
prf->other_secret = mbedtls_calloc(1, data_length);
if (prf->other_secret == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
memcpy(prf->other_secret, data, data_length);
prf->other_secret_length = data_length;
} else {
prf->other_secret_length = 0;
}
prf->state = PSA_TLS12_PRF_STATE_OTHER_KEY_SET;
return PSA_SUCCESS;
}
static psa_status_t psa_tls12_prf_psk_to_ms_input(
psa_tls12_prf_key_derivation_t *prf,
psa_key_derivation_step_t step,
const uint8_t *data,
size_t data_length)
{
switch (step) {
case PSA_KEY_DERIVATION_INPUT_SECRET:
return psa_tls12_prf_psk_to_ms_set_key(prf,
data, data_length);
break;
case PSA_KEY_DERIVATION_INPUT_OTHER_SECRET:
return psa_tls12_prf_psk_to_ms_set_other_key(prf,
data,
data_length);
break;
default:
return psa_tls12_prf_input(prf, step, data, data_length);
break;
}
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS)
static psa_status_t psa_tls12_ecjpake_to_pms_input(
psa_tls12_ecjpake_to_pms_t *ecjpake,
psa_key_derivation_step_t step,
const uint8_t *data,
size_t data_length)
{
if (data_length != PSA_TLS12_ECJPAKE_TO_PMS_INPUT_SIZE ||
step != PSA_KEY_DERIVATION_INPUT_SECRET) {
return PSA_ERROR_INVALID_ARGUMENT;
}
/* Check if the passed point is in an uncompressed form */
if (data[0] != 0x04) {
return PSA_ERROR_INVALID_ARGUMENT;
}
/* Only K.X has to be extracted - bytes 1 to 32 inclusive. */
memcpy(ecjpake->data, data + 1, PSA_TLS12_ECJPAKE_TO_PMS_DATA_SIZE);
return PSA_SUCCESS;
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS */
#if defined(PSA_HAVE_SOFT_PBKDF2)
static psa_status_t psa_pbkdf2_set_input_cost(
psa_pbkdf2_key_derivation_t *pbkdf2,
psa_key_derivation_step_t step,
uint64_t data)
{
if (step != PSA_KEY_DERIVATION_INPUT_COST) {
return PSA_ERROR_INVALID_ARGUMENT;
}
if (pbkdf2->state != PSA_PBKDF2_STATE_INIT) {
return PSA_ERROR_BAD_STATE;
}
if (data > PSA_VENDOR_PBKDF2_MAX_ITERATIONS) {
return PSA_ERROR_NOT_SUPPORTED;
}
if (data == 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
pbkdf2->input_cost = data;
pbkdf2->state = PSA_PBKDF2_STATE_INPUT_COST_SET;
return PSA_SUCCESS;
}
static psa_status_t psa_pbkdf2_set_salt(psa_pbkdf2_key_derivation_t *pbkdf2,
const uint8_t *data,
size_t data_length)
{
if (pbkdf2->state == PSA_PBKDF2_STATE_INPUT_COST_SET) {
pbkdf2->state = PSA_PBKDF2_STATE_SALT_SET;
} else if (pbkdf2->state == PSA_PBKDF2_STATE_SALT_SET) {
/* Appending to existing salt. No state change. */
} else {
return PSA_ERROR_BAD_STATE;
}
if (data_length == 0) {
/* Appending an empty string, nothing to do. */
} else {
uint8_t *next_salt;
next_salt = mbedtls_calloc(1, data_length + pbkdf2->salt_length);
if (next_salt == NULL) {
return PSA_ERROR_INSUFFICIENT_MEMORY;
}
if (pbkdf2->salt_length != 0) {
memcpy(next_salt, pbkdf2->salt, pbkdf2->salt_length);
}
memcpy(next_salt + pbkdf2->salt_length, data, data_length);
pbkdf2->salt_length += data_length;
mbedtls_free(pbkdf2->salt);
pbkdf2->salt = next_salt;
}
return PSA_SUCCESS;
}
#if defined(MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_HMAC)
static psa_status_t psa_pbkdf2_hmac_set_password(psa_algorithm_t hash_alg,
const uint8_t *input,
size_t input_len,
uint8_t *output,
size_t *output_len)
{
psa_status_t status = PSA_SUCCESS;
if (input_len > PSA_HASH_BLOCK_LENGTH(hash_alg)) {
status = psa_hash_compute(hash_alg, input, input_len, output,
PSA_HMAC_MAX_HASH_BLOCK_SIZE, output_len);
} else {
memcpy(output, input, input_len);
*output_len = PSA_HASH_BLOCK_LENGTH(hash_alg);
}
return status;
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_HMAC */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_AES_CMAC_PRF_128)
static psa_status_t psa_pbkdf2_cmac_set_password(const uint8_t *input,
size_t input_len,
uint8_t *output,
size_t *output_len)
{
psa_status_t status = PSA_SUCCESS;
if (input_len != PSA_MAC_LENGTH(PSA_KEY_TYPE_AES, 128U, PSA_ALG_CMAC)) {
psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
uint8_t zeros[16] = { 0 };
psa_set_key_type(&attributes, PSA_KEY_TYPE_AES);
psa_set_key_bits(&attributes, PSA_BYTES_TO_BITS(sizeof(zeros)));
psa_set_key_usage_flags(&attributes, PSA_KEY_USAGE_SIGN_MESSAGE);
/* Passing PSA_MAC_LENGTH(PSA_KEY_TYPE_AES, 128U, PSA_ALG_CMAC) as
* mac_size as the driver function sets mac_output_length = mac_size
* on success. See https://github.com/Mbed-TLS/mbedtls/issues/7801 */
status = psa_driver_wrapper_mac_compute(&attributes,
zeros, sizeof(zeros),
PSA_ALG_CMAC, input, input_len,
output,
PSA_MAC_LENGTH(PSA_KEY_TYPE_AES,
128U,
PSA_ALG_CMAC),
output_len);
} else {
memcpy(output, input, input_len);
*output_len = PSA_MAC_LENGTH(PSA_KEY_TYPE_AES, 128U, PSA_ALG_CMAC);
}
return status;
}
#endif /* MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_AES_CMAC_PRF_128 */
static psa_status_t psa_pbkdf2_set_password(psa_pbkdf2_key_derivation_t *pbkdf2,
psa_algorithm_t kdf_alg,
const uint8_t *data,
size_t data_length)
{
psa_status_t status = PSA_SUCCESS;
if (pbkdf2->state != PSA_PBKDF2_STATE_SALT_SET) {
return PSA_ERROR_BAD_STATE;
}
#if defined(MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_HMAC)
if (PSA_ALG_IS_PBKDF2_HMAC(kdf_alg)) {
psa_algorithm_t hash_alg = PSA_ALG_PBKDF2_HMAC_GET_HASH(kdf_alg);
status = psa_pbkdf2_hmac_set_password(hash_alg, data, data_length,
pbkdf2->password,
&pbkdf2->password_length);
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_HMAC */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_AES_CMAC_PRF_128)
if (kdf_alg == PSA_ALG_PBKDF2_AES_CMAC_PRF_128) {
status = psa_pbkdf2_cmac_set_password(data, data_length,
pbkdf2->password,
&pbkdf2->password_length);
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_AES_CMAC_PRF_128 */
{
return PSA_ERROR_INVALID_ARGUMENT;
}
pbkdf2->state = PSA_PBKDF2_STATE_PASSWORD_SET;
return status;
}
static psa_status_t psa_pbkdf2_input(psa_pbkdf2_key_derivation_t *pbkdf2,
psa_algorithm_t kdf_alg,
psa_key_derivation_step_t step,
const uint8_t *data,
size_t data_length)
{
switch (step) {
case PSA_KEY_DERIVATION_INPUT_SALT:
return psa_pbkdf2_set_salt(pbkdf2, data, data_length);
case PSA_KEY_DERIVATION_INPUT_PASSWORD:
return psa_pbkdf2_set_password(pbkdf2, kdf_alg, data, data_length);
default:
return PSA_ERROR_INVALID_ARGUMENT;
}
}
#endif /* PSA_HAVE_SOFT_PBKDF2 */
/** Check whether the given key type is acceptable for the given
* input step of a key derivation.
*
* Secret inputs must have the type #PSA_KEY_TYPE_DERIVE.
* Non-secret inputs must have the type #PSA_KEY_TYPE_RAW_DATA.
* Both secret and non-secret inputs can alternatively have the type
* #PSA_KEY_TYPE_NONE, which is never the type of a key object, meaning
* that the input was passed as a buffer rather than via a key object.
*/
static int psa_key_derivation_check_input_type(
psa_key_derivation_step_t step,
psa_key_type_t key_type)
{
switch (step) {
case PSA_KEY_DERIVATION_INPUT_SECRET:
if (key_type == PSA_KEY_TYPE_DERIVE) {
return PSA_SUCCESS;
}
if (key_type == PSA_KEY_TYPE_NONE) {
return PSA_SUCCESS;
}
break;
case PSA_KEY_DERIVATION_INPUT_OTHER_SECRET:
if (key_type == PSA_KEY_TYPE_DERIVE) {
return PSA_SUCCESS;
}
if (key_type == PSA_KEY_TYPE_NONE) {
return PSA_SUCCESS;
}
break;
case PSA_KEY_DERIVATION_INPUT_LABEL:
case PSA_KEY_DERIVATION_INPUT_SALT:
case PSA_KEY_DERIVATION_INPUT_INFO:
case PSA_KEY_DERIVATION_INPUT_SEED:
if (key_type == PSA_KEY_TYPE_RAW_DATA) {
return PSA_SUCCESS;
}
if (key_type == PSA_KEY_TYPE_NONE) {
return PSA_SUCCESS;
}
break;
case PSA_KEY_DERIVATION_INPUT_PASSWORD:
if (key_type == PSA_KEY_TYPE_PASSWORD) {
return PSA_SUCCESS;
}
if (key_type == PSA_KEY_TYPE_DERIVE) {
return PSA_SUCCESS;
}
if (key_type == PSA_KEY_TYPE_NONE) {
return PSA_SUCCESS;
}
break;
}
return PSA_ERROR_INVALID_ARGUMENT;
}
static psa_status_t psa_key_derivation_input_internal(
psa_key_derivation_operation_t *operation,
psa_key_derivation_step_t step,
psa_key_type_t key_type,
const uint8_t *data,
size_t data_length)
{
psa_status_t status;
psa_algorithm_t kdf_alg = psa_key_derivation_get_kdf_alg(operation);
status = psa_key_derivation_check_input_type(step, key_type);
if (status != PSA_SUCCESS) {
goto exit;
}
#if defined(BUILTIN_ALG_ANY_HKDF)
if (PSA_ALG_IS_ANY_HKDF(kdf_alg)) {
status = psa_hkdf_input(&operation->ctx.hkdf, kdf_alg,
step, data, data_length);
} else
#endif /* BUILTIN_ALG_ANY_HKDF */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF)
if (PSA_ALG_IS_TLS12_PRF(kdf_alg)) {
status = psa_tls12_prf_input(&operation->ctx.tls12_prf,
step, data, data_length);
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS)
if (PSA_ALG_IS_TLS12_PSK_TO_MS(kdf_alg)) {
status = psa_tls12_prf_psk_to_ms_input(&operation->ctx.tls12_prf,
step, data, data_length);
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS)
if (kdf_alg == PSA_ALG_TLS12_ECJPAKE_TO_PMS) {
status = psa_tls12_ecjpake_to_pms_input(
&operation->ctx.tls12_ecjpake_to_pms, step, data, data_length);
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_ECJPAKE_TO_PMS */
#if defined(PSA_HAVE_SOFT_PBKDF2)
if (PSA_ALG_IS_PBKDF2(kdf_alg)) {
status = psa_pbkdf2_input(&operation->ctx.pbkdf2, kdf_alg,
step, data, data_length);
} else
#endif /* PSA_HAVE_SOFT_PBKDF2 */
{
/* This can't happen unless the operation object was not initialized */
(void) data;
(void) data_length;
(void) kdf_alg;
return PSA_ERROR_BAD_STATE;
}
exit:
if (status != PSA_SUCCESS) {
psa_key_derivation_abort(operation);
}
return status;
}
static psa_status_t psa_key_derivation_input_integer_internal(
psa_key_derivation_operation_t *operation,
psa_key_derivation_step_t step,
uint64_t value)
{
psa_status_t status;
psa_algorithm_t kdf_alg = psa_key_derivation_get_kdf_alg(operation);
#if defined(PSA_HAVE_SOFT_PBKDF2)
if (PSA_ALG_IS_PBKDF2(kdf_alg)) {
status = psa_pbkdf2_set_input_cost(
&operation->ctx.pbkdf2, step, value);
} else
#endif /* PSA_HAVE_SOFT_PBKDF2 */
{
(void) step;
(void) value;
(void) kdf_alg;
status = PSA_ERROR_INVALID_ARGUMENT;
}
if (status != PSA_SUCCESS) {
psa_key_derivation_abort(operation);
}
return status;
}
psa_status_t psa_key_derivation_input_bytes(
psa_key_derivation_operation_t *operation,
psa_key_derivation_step_t step,
const uint8_t *data,
size_t data_length)
{
return psa_key_derivation_input_internal(operation, step,
PSA_KEY_TYPE_NONE,
data, data_length);
}
psa_status_t psa_key_derivation_input_integer(
psa_key_derivation_operation_t *operation,
psa_key_derivation_step_t step,
uint64_t value)
{
return psa_key_derivation_input_integer_internal(operation, step, value);
}
psa_status_t psa_key_derivation_input_key(
psa_key_derivation_operation_t *operation,
psa_key_derivation_step_t step,
mbedtls_svc_key_id_t key)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
status = psa_get_and_lock_transparent_key_slot_with_policy(
key, &slot, PSA_KEY_USAGE_DERIVE, operation->alg);
if (status != PSA_SUCCESS) {
psa_key_derivation_abort(operation);
return status;
}
/* Passing a key object as a SECRET or PASSWORD input unlocks the
* permission to output to a key object. */
if (step == PSA_KEY_DERIVATION_INPUT_SECRET ||
step == PSA_KEY_DERIVATION_INPUT_PASSWORD) {
operation->can_output_key = 1;
}
status = psa_key_derivation_input_internal(operation,
step, slot->attr.type,
slot->key.data,
slot->key.bytes);
unlock_status = psa_unregister_read(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
/****************************************************************/
/* Key agreement */
/****************************************************************/
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)
{
switch (alg) {
#if defined(MBEDTLS_PSA_BUILTIN_ALG_ECDH)
case PSA_ALG_ECDH:
return mbedtls_psa_key_agreement_ecdh(attributes, key_buffer,
key_buffer_size, alg,
peer_key, peer_key_length,
shared_secret,
shared_secret_size,
shared_secret_length);
#endif /* MBEDTLS_PSA_BUILTIN_ALG_ECDH */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_FFDH)
case PSA_ALG_FFDH:
return mbedtls_psa_ffdh_key_agreement(attributes,
peer_key,
peer_key_length,
key_buffer,
key_buffer_size,
shared_secret,
shared_secret_size,
shared_secret_length);
#endif /* MBEDTLS_PSA_BUILTIN_ALG_FFDH */
default:
(void) attributes;
(void) key_buffer;
(void) key_buffer_size;
(void) peer_key;
(void) peer_key_length;
(void) shared_secret;
(void) shared_secret_size;
(void) shared_secret_length;
return PSA_ERROR_NOT_SUPPORTED;
}
}
/** Internal function for raw key agreement
* Calls the driver wrapper which will hand off key agreement task
* to the driver's implementation if a driver is present.
* Fallback specified in the driver wrapper is built-in raw key agreement
* (psa_key_agreement_raw_builtin).
*/
static psa_status_t psa_key_agreement_raw_internal(psa_algorithm_t alg,
psa_key_slot_t *private_key,
const uint8_t *peer_key,
size_t peer_key_length,
uint8_t *shared_secret,
size_t shared_secret_size,
size_t *shared_secret_length)
{
if (!PSA_ALG_IS_RAW_KEY_AGREEMENT(alg)) {
return PSA_ERROR_NOT_SUPPORTED;
}
psa_key_attributes_t attributes = {
.core = private_key->attr
};
return psa_driver_wrapper_key_agreement(&attributes,
private_key->key.data,
private_key->key.bytes, alg,
peer_key, peer_key_length,
shared_secret,
shared_secret_size,
shared_secret_length);
}
/* Note that if this function fails, you must call psa_key_derivation_abort()
* to potentially free embedded data structures and wipe confidential data.
*/
static psa_status_t psa_key_agreement_internal(psa_key_derivation_operation_t *operation,
psa_key_derivation_step_t step,
psa_key_slot_t *private_key,
const uint8_t *peer_key,
size_t peer_key_length)
{
psa_status_t status;
uint8_t shared_secret[PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE];
size_t shared_secret_length = 0;
psa_algorithm_t ka_alg = PSA_ALG_KEY_AGREEMENT_GET_BASE(operation->alg);
/* Step 1: run the secret agreement algorithm to generate the shared
* secret. */
status = psa_key_agreement_raw_internal(ka_alg,
private_key,
peer_key, peer_key_length,
shared_secret,
sizeof(shared_secret),
&shared_secret_length);
if (status != PSA_SUCCESS) {
goto exit;
}
/* Step 2: set up the key derivation to generate key material from
* the shared secret. A shared secret is permitted wherever a key
* of type DERIVE is permitted. */
status = psa_key_derivation_input_internal(operation, step,
PSA_KEY_TYPE_DERIVE,
shared_secret,
shared_secret_length);
exit:
mbedtls_platform_zeroize(shared_secret, shared_secret_length);
return status;
}
psa_status_t psa_key_derivation_key_agreement(psa_key_derivation_operation_t *operation,
psa_key_derivation_step_t step,
mbedtls_svc_key_id_t private_key,
const uint8_t *peer_key,
size_t peer_key_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot;
if (!PSA_ALG_IS_KEY_AGREEMENT(operation->alg)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
status = psa_get_and_lock_transparent_key_slot_with_policy(
private_key, &slot, PSA_KEY_USAGE_DERIVE, operation->alg);
if (status != PSA_SUCCESS) {
return status;
}
status = psa_key_agreement_internal(operation, step,
slot,
peer_key, peer_key_length);
if (status != PSA_SUCCESS) {
psa_key_derivation_abort(operation);
} else {
/* If a private key has been added as SECRET, we allow the derived
* key material to be used as a key in PSA Crypto. */
if (step == PSA_KEY_DERIVATION_INPUT_SECRET) {
operation->can_output_key = 1;
}
}
unlock_status = psa_unregister_read(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
psa_status_t psa_raw_key_agreement(psa_algorithm_t alg,
mbedtls_svc_key_id_t private_key,
const uint8_t *peer_key,
size_t peer_key_length,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot = NULL;
size_t expected_length;
if (!PSA_ALG_IS_KEY_AGREEMENT(alg)) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
status = psa_get_and_lock_transparent_key_slot_with_policy(
private_key, &slot, PSA_KEY_USAGE_DERIVE, alg);
if (status != PSA_SUCCESS) {
goto exit;
}
/* PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE() is in general an upper bound
* for the output size. The PSA specification only guarantees that this
* function works if output_size >= PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE(...),
* but it might be nice to allow smaller buffers if the output fits.
* At the time of writing this comment, with only ECDH implemented,
* PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE() is exact so the point is moot.
* If FFDH is implemented, PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE() can easily
* be exact for it as well. */
expected_length =
PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE(slot->attr.type, slot->attr.bits);
if (output_size < expected_length) {
status = PSA_ERROR_BUFFER_TOO_SMALL;
goto exit;
}
status = psa_key_agreement_raw_internal(alg, slot,
peer_key, peer_key_length,
output, output_size,
output_length);
exit:
if (status != PSA_SUCCESS) {
/* If an error happens and is not handled properly, the output
* may be used as a key to protect sensitive data. Arrange for such
* a key to be random, which is likely to result in decryption or
* verification errors. This is better than filling the buffer with
* some constant data such as zeros, which would result in the data
* being protected with a reproducible, easily knowable key.
*/
psa_generate_random(output, output_size);
*output_length = output_size;
}
unlock_status = psa_unregister_read_under_mutex(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
/****************************************************************/
/* Random generation */
/****************************************************************/
#if defined(MBEDTLS_PSA_INJECT_ENTROPY)
#include "entropy_poll.h"
#endif
/** Initialize the PSA random generator.
*/
static void mbedtls_psa_random_init(mbedtls_psa_random_context_t *rng)
{
#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
memset(rng, 0, sizeof(*rng));
#else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
/* Set default configuration if
* mbedtls_psa_crypto_configure_entropy_sources() hasn't been called. */
if (rng->entropy_init == NULL) {
rng->entropy_init = mbedtls_entropy_init;
}
if (rng->entropy_free == NULL) {
rng->entropy_free = mbedtls_entropy_free;
}
rng->entropy_init(&rng->entropy);
#if defined(MBEDTLS_PSA_INJECT_ENTROPY) && \
defined(MBEDTLS_NO_DEFAULT_ENTROPY_SOURCES)
/* The PSA entropy injection feature depends on using NV seed as an entropy
* source. Add NV seed as an entropy source for PSA entropy injection. */
mbedtls_entropy_add_source(&rng->entropy,
mbedtls_nv_seed_poll, NULL,
MBEDTLS_ENTROPY_BLOCK_SIZE,
MBEDTLS_ENTROPY_SOURCE_STRONG);
#endif
mbedtls_psa_drbg_init(MBEDTLS_PSA_RANDOM_STATE);
#endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
}
/** Deinitialize the PSA random generator.
*/
static void mbedtls_psa_random_free(mbedtls_psa_random_context_t *rng)
{
#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
memset(rng, 0, sizeof(*rng));
#else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
mbedtls_psa_drbg_free(MBEDTLS_PSA_RANDOM_STATE);
rng->entropy_free(&rng->entropy);
#endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
}
/** Seed the PSA random generator.
*/
static psa_status_t mbedtls_psa_random_seed(mbedtls_psa_random_context_t *rng)
{
#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
/* Do nothing: the external RNG seeds itself. */
(void) rng;
return PSA_SUCCESS;
#else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
const unsigned char drbg_seed[] = "PSA";
int ret = mbedtls_psa_drbg_seed(&rng->entropy,
drbg_seed, sizeof(drbg_seed) - 1);
return mbedtls_to_psa_error(ret);
#endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
}
psa_status_t psa_generate_random(uint8_t *output,
size_t output_size)
{
GUARD_MODULE_INITIALIZED;
#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
size_t output_length = 0;
psa_status_t status = mbedtls_psa_external_get_random(&global_data.rng,
output, output_size,
&output_length);
if (status != PSA_SUCCESS) {
return status;
}
/* Breaking up a request into smaller chunks is currently not supported
* for the external RNG interface. */
if (output_length != output_size) {
return PSA_ERROR_INSUFFICIENT_ENTROPY;
}
return PSA_SUCCESS;
#else /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
while (output_size > 0) {
size_t request_size =
(output_size > MBEDTLS_PSA_RANDOM_MAX_REQUEST ?
MBEDTLS_PSA_RANDOM_MAX_REQUEST :
output_size);
int ret = mbedtls_psa_get_random(MBEDTLS_PSA_RANDOM_STATE,
output, request_size);
if (ret != 0) {
return mbedtls_to_psa_error(ret);
}
output_size -= request_size;
output += request_size;
}
return PSA_SUCCESS;
#endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
}
/* Wrapper function allowing the classic API to use the PSA RNG.
*
* `mbedtls_psa_get_random(MBEDTLS_PSA_RANDOM_STATE, ...)` calls
* `psa_generate_random(...)`. The state parameter is ignored since the
* PSA API doesn't support passing an explicit state.
*
* In the non-external case, psa_generate_random() calls an
* `mbedtls_xxx_drbg_random` function which has exactly the same signature
* and semantics as mbedtls_psa_get_random(). As an optimization,
* instead of doing this back-and-forth between the PSA API and the
* classic API, psa_crypto_random_impl.h defines `mbedtls_psa_get_random`
* as a constant function pointer to `mbedtls_xxx_drbg_random`.
*/
#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
int mbedtls_psa_get_random(void *p_rng,
unsigned char *output,
size_t output_size)
{
/* This function takes a pointer to the RNG state because that's what
* classic mbedtls functions using an RNG expect. The PSA RNG manages
* its own state internally and doesn't let the caller access that state.
* So we just ignore the state parameter, and in practice we'll pass
* NULL. */
(void) p_rng;
psa_status_t status = psa_generate_random(output, output_size);
if (status == PSA_SUCCESS) {
return 0;
} else {
return MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
}
}
#endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
#if defined(MBEDTLS_PSA_INJECT_ENTROPY)
psa_status_t mbedtls_psa_inject_entropy(const uint8_t *seed,
size_t seed_size)
{
if (global_data.initialized) {
return PSA_ERROR_NOT_PERMITTED;
}
if (((seed_size < MBEDTLS_ENTROPY_MIN_PLATFORM) ||
(seed_size < MBEDTLS_ENTROPY_BLOCK_SIZE)) ||
(seed_size > MBEDTLS_ENTROPY_MAX_SEED_SIZE)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
return mbedtls_psa_storage_inject_entropy(seed, seed_size);
}
#endif /* MBEDTLS_PSA_INJECT_ENTROPY */
/** Validate the key type and size for key generation
*
* \param type The key type
* \param 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.
*/
static psa_status_t psa_validate_key_type_and_size_for_key_generation(
psa_key_type_t type, size_t bits)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (key_type_is_raw_bytes(type)) {
status = psa_validate_unstructured_key_bit_size(type, bits);
if (status != PSA_SUCCESS) {
return status;
}
} else
#if defined(PSA_WANT_KEY_TYPE_RSA_KEY_PAIR_GENERATE)
if (PSA_KEY_TYPE_IS_RSA(type) && PSA_KEY_TYPE_IS_KEY_PAIR(type)) {
if (bits > PSA_VENDOR_RSA_MAX_KEY_BITS) {
return PSA_ERROR_NOT_SUPPORTED;
}
if (bits < PSA_VENDOR_RSA_GENERATE_MIN_KEY_BITS) {
return PSA_ERROR_NOT_SUPPORTED;
}
/* Accept only byte-aligned keys, for the same reasons as
* in psa_import_rsa_key(). */
if (bits % 8 != 0) {
return PSA_ERROR_NOT_SUPPORTED;
}
} else
#endif /* defined(PSA_WANT_KEY_TYPE_RSA_KEY_PAIR_GENERATE) */
#if defined(PSA_WANT_KEY_TYPE_ECC_KEY_PAIR_GENERATE)
if (PSA_KEY_TYPE_IS_ECC(type) && PSA_KEY_TYPE_IS_KEY_PAIR(type)) {
/* To avoid empty block, return successfully here. */
return PSA_SUCCESS;
} else
#endif /* defined(PSA_WANT_KEY_TYPE_ECC_KEY_PAIR_GENERATE) */
#if defined(PSA_WANT_KEY_TYPE_DH_KEY_PAIR_GENERATE)
if (PSA_KEY_TYPE_IS_DH(type) && PSA_KEY_TYPE_IS_KEY_PAIR(type)) {
if (psa_is_dh_key_size_valid(bits) == 0) {
return PSA_ERROR_NOT_SUPPORTED;
}
} else
#endif /* defined(PSA_WANT_KEY_TYPE_DH_KEY_PAIR_GENERATE) */
{
return PSA_ERROR_NOT_SUPPORTED;
}
return PSA_SUCCESS;
}
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)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_type_t type = attributes->core.type;
if ((attributes->domain_parameters == NULL) &&
(attributes->domain_parameters_size != 0)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
if (key_type_is_raw_bytes(type)) {
status = psa_generate_random(key_buffer, key_buffer_size);
if (status != PSA_SUCCESS) {
return status;
}
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES)
if (type == PSA_KEY_TYPE_DES) {
psa_des_set_key_parity(key_buffer, key_buffer_size);
}
#endif /* MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES */
} else
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_GENERATE)
if (type == PSA_KEY_TYPE_RSA_KEY_PAIR) {
return mbedtls_psa_rsa_generate_key(attributes,
key_buffer,
key_buffer_size,
key_buffer_length);
} else
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_GENERATE) */
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_GENERATE)
if (PSA_KEY_TYPE_IS_ECC(type) && PSA_KEY_TYPE_IS_KEY_PAIR(type)) {
return mbedtls_psa_ecp_generate_key(attributes,
key_buffer,
key_buffer_size,
key_buffer_length);
} else
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_ECC_KEY_PAIR_GENERATE) */
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR_GENERATE)
if (PSA_KEY_TYPE_IS_DH(type) && PSA_KEY_TYPE_IS_KEY_PAIR(type)) {
return mbedtls_psa_ffdh_generate_key(attributes,
key_buffer,
key_buffer_size,
key_buffer_length);
} else
#endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DH_KEY_PAIR_GENERATE) */
{
(void) key_buffer_length;
return PSA_ERROR_NOT_SUPPORTED;
}
return PSA_SUCCESS;
}
psa_status_t psa_generate_key(const psa_key_attributes_t *attributes,
mbedtls_svc_key_id_t *key)
{
psa_status_t status;
psa_key_slot_t *slot = NULL;
psa_se_drv_table_entry_t *driver = NULL;
size_t key_buffer_size;
*key = MBEDTLS_SVC_KEY_ID_INIT;
/* Reject any attempt to create a zero-length key so that we don't
* risk tripping up later, e.g. on a malloc(0) that returns NULL. */
if (psa_get_key_bits(attributes) == 0) {
return PSA_ERROR_INVALID_ARGUMENT;
}
/* Reject any attempt to create a public key. */
if (PSA_KEY_TYPE_IS_PUBLIC_KEY(attributes->core.type)) {
return PSA_ERROR_INVALID_ARGUMENT;
}
status = psa_start_key_creation(PSA_KEY_CREATION_GENERATE, attributes,
&slot, &driver);
if (status != PSA_SUCCESS) {
goto exit;
}
/* In the case of a transparent key or an opaque key stored in local
* storage ( thus not in the case of generating a key in a secure element
* with storage ( MBEDTLS_PSA_CRYPTO_SE_C ) ),we have to allocate a
* buffer to hold the generated key material. */
if (slot->key.data == NULL) {
if (PSA_KEY_LIFETIME_GET_LOCATION(attributes->core.lifetime) ==
PSA_KEY_LOCATION_LOCAL_STORAGE) {
status = psa_validate_key_type_and_size_for_key_generation(
attributes->core.type, attributes->core.bits);
if (status != PSA_SUCCESS) {
goto exit;
}
key_buffer_size = PSA_EXPORT_KEY_OUTPUT_SIZE(
attributes->core.type,
attributes->core.bits);
} else {
status = psa_driver_wrapper_get_key_buffer_size(
attributes, &key_buffer_size);
if (status != PSA_SUCCESS) {
goto exit;
}
}
status = psa_allocate_buffer_to_slot(slot, key_buffer_size);
if (status != PSA_SUCCESS) {
goto exit;
}
}
status = psa_driver_wrapper_generate_key(attributes,
slot->key.data, slot->key.bytes, &slot->key.bytes);
if (status != PSA_SUCCESS) {
psa_remove_key_data_from_memory(slot);
}
exit:
if (status == PSA_SUCCESS) {
status = psa_finish_key_creation(slot, driver, key);
}
if (status != PSA_SUCCESS) {
psa_fail_key_creation(slot, driver);
}
return status;
}
/****************************************************************/
/* Module setup */
/****************************************************************/
#if !defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
psa_status_t mbedtls_psa_crypto_configure_entropy_sources(
void (* entropy_init)(mbedtls_entropy_context *ctx),
void (* entropy_free)(mbedtls_entropy_context *ctx))
{
if (global_data.rng_state != RNG_NOT_INITIALIZED) {
return PSA_ERROR_BAD_STATE;
}
global_data.rng.entropy_init = entropy_init;
global_data.rng.entropy_free = entropy_free;
return PSA_SUCCESS;
}
#endif /* !defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG) */
void mbedtls_psa_crypto_free(void)
{
psa_wipe_all_key_slots();
if (global_data.rng_state != RNG_NOT_INITIALIZED) {
mbedtls_psa_random_free(&global_data.rng);
}
/* Wipe all remaining data, including configuration.
* In particular, this sets all state indicator to the value
* indicating "uninitialized". */
mbedtls_platform_zeroize(&global_data, sizeof(global_data));
/* Terminate drivers */
psa_driver_wrapper_free();
}
#if defined(PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS)
/** Recover a transaction that was interrupted by a power failure.
*
* This function is called during initialization, before psa_crypto_init()
* returns. If this function returns a failure status, the initialization
* fails.
*/
static psa_status_t psa_crypto_recover_transaction(
const psa_crypto_transaction_t *transaction)
{
switch (transaction->unknown.type) {
case PSA_CRYPTO_TRANSACTION_CREATE_KEY:
case PSA_CRYPTO_TRANSACTION_DESTROY_KEY:
/* TODO - fall through to the failure case until this
* is implemented.
* https://github.com/ARMmbed/mbed-crypto/issues/218
*/
default:
/* We found an unsupported transaction in the storage.
* We don't know what state the storage is in. Give up. */
return PSA_ERROR_DATA_INVALID;
}
}
#endif /* PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS */
psa_status_t psa_crypto_init(void)
{
psa_status_t status;
/* Double initialization is explicitly allowed. */
if (global_data.initialized != 0) {
return PSA_SUCCESS;
}
/* Init drivers */
status = psa_driver_wrapper_init();
if (status != PSA_SUCCESS) {
goto exit;
}
global_data.drivers_initialized = 1;
status = psa_initialize_key_slots();
if (status != PSA_SUCCESS) {
goto exit;
}
/* Initialize and seed the random generator. */
mbedtls_psa_random_init(&global_data.rng);
global_data.rng_state = RNG_INITIALIZED;
status = mbedtls_psa_random_seed(&global_data.rng);
if (status != PSA_SUCCESS) {
goto exit;
}
global_data.rng_state = RNG_SEEDED;
#if defined(PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS)
status = psa_crypto_load_transaction();
if (status == PSA_SUCCESS) {
status = psa_crypto_recover_transaction(&psa_crypto_transaction);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_crypto_stop_transaction();
} else if (status == PSA_ERROR_DOES_NOT_EXIST) {
/* There's no transaction to complete. It's all good. */
status = PSA_SUCCESS;
}
#endif /* PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS */
/* All done. */
global_data.initialized = 1;
exit:
if (status != PSA_SUCCESS) {
mbedtls_psa_crypto_free();
}
return status;
}
#if defined(PSA_WANT_ALG_SOME_PAKE)
psa_status_t psa_crypto_driver_pake_get_password_len(
const psa_crypto_driver_pake_inputs_t *inputs,
size_t *password_len)
{
if (inputs->password_len == 0) {
return PSA_ERROR_BAD_STATE;
}
*password_len = inputs->password_len;
return PSA_SUCCESS;
}
psa_status_t psa_crypto_driver_pake_get_password(
const psa_crypto_driver_pake_inputs_t *inputs,
uint8_t *buffer, size_t buffer_size, size_t *buffer_length)
{
if (inputs->password_len == 0) {
return PSA_ERROR_BAD_STATE;
}
if (buffer_size < inputs->password_len) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
memcpy(buffer, inputs->password, inputs->password_len);
*buffer_length = inputs->password_len;
return PSA_SUCCESS;
}
psa_status_t psa_crypto_driver_pake_get_user_len(
const psa_crypto_driver_pake_inputs_t *inputs,
size_t *user_len)
{
if (inputs->user_len == 0) {
return PSA_ERROR_BAD_STATE;
}
*user_len = inputs->user_len;
return PSA_SUCCESS;
}
psa_status_t psa_crypto_driver_pake_get_user(
const psa_crypto_driver_pake_inputs_t *inputs,
uint8_t *user_id, size_t user_id_size, size_t *user_id_len)
{
if (inputs->user_len == 0) {
return PSA_ERROR_BAD_STATE;
}
if (user_id_size < inputs->user_len) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
memcpy(user_id, inputs->user, inputs->user_len);
*user_id_len = inputs->user_len;
return PSA_SUCCESS;
}
psa_status_t psa_crypto_driver_pake_get_peer_len(
const psa_crypto_driver_pake_inputs_t *inputs,
size_t *peer_len)
{
if (inputs->peer_len == 0) {
return PSA_ERROR_BAD_STATE;
}
*peer_len = inputs->peer_len;
return PSA_SUCCESS;
}
psa_status_t psa_crypto_driver_pake_get_peer(
const psa_crypto_driver_pake_inputs_t *inputs,
uint8_t *peer_id, size_t peer_id_size, size_t *peer_id_length)
{
if (inputs->peer_len == 0) {
return PSA_ERROR_BAD_STATE;
}
if (peer_id_size < inputs->peer_len) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
memcpy(peer_id, inputs->peer, inputs->peer_len);
*peer_id_length = inputs->peer_len;
return PSA_SUCCESS;
}
psa_status_t psa_crypto_driver_pake_get_cipher_suite(
const psa_crypto_driver_pake_inputs_t *inputs,
psa_pake_cipher_suite_t *cipher_suite)
{
if (inputs->cipher_suite.algorithm == PSA_ALG_NONE) {
return PSA_ERROR_BAD_STATE;
}
*cipher_suite = inputs->cipher_suite;
return PSA_SUCCESS;
}
psa_status_t psa_pake_setup(
psa_pake_operation_t *operation,
const psa_pake_cipher_suite_t *cipher_suite)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->stage != PSA_PAKE_OPERATION_STAGE_SETUP) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (PSA_ALG_IS_PAKE(cipher_suite->algorithm) == 0 ||
PSA_ALG_IS_HASH(cipher_suite->hash) == 0) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
memset(&operation->data.inputs, 0, sizeof(operation->data.inputs));
operation->alg = cipher_suite->algorithm;
operation->primitive = PSA_PAKE_PRIMITIVE(cipher_suite->type,
cipher_suite->family, cipher_suite->bits);
operation->data.inputs.cipher_suite = *cipher_suite;
#if defined(PSA_WANT_ALG_JPAKE)
if (operation->alg == PSA_ALG_JPAKE) {
psa_jpake_computation_stage_t *computation_stage =
&operation->computation_stage.jpake;
memset(computation_stage, 0, sizeof(*computation_stage));
computation_stage->step = PSA_PAKE_STEP_KEY_SHARE;
} else
#endif /* PSA_WANT_ALG_JPAKE */
{
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
operation->stage = PSA_PAKE_OPERATION_STAGE_COLLECT_INPUTS;
return PSA_SUCCESS;
exit:
psa_pake_abort(operation);
return status;
}
psa_status_t psa_pake_set_password_key(
psa_pake_operation_t *operation,
mbedtls_svc_key_id_t password)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t unlock_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_slot_t *slot = NULL;
psa_key_attributes_t attributes;
psa_key_type_t type;
if (operation->stage != PSA_PAKE_OPERATION_STAGE_COLLECT_INPUTS) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
status = psa_get_and_lock_key_slot_with_policy(password, &slot,
PSA_KEY_USAGE_DERIVE,
operation->alg);
if (status != PSA_SUCCESS) {
goto exit;
}
attributes = (psa_key_attributes_t) {
.core = slot->attr
};
type = psa_get_key_type(&attributes);
if (type != PSA_KEY_TYPE_PASSWORD &&
type != PSA_KEY_TYPE_PASSWORD_HASH) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
operation->data.inputs.password = mbedtls_calloc(1, slot->key.bytes);
if (operation->data.inputs.password == NULL) {
status = PSA_ERROR_INSUFFICIENT_MEMORY;
goto exit;
}
memcpy(operation->data.inputs.password, slot->key.data, slot->key.bytes);
operation->data.inputs.password_len = slot->key.bytes;
operation->data.inputs.attributes = attributes;
exit:
if (status != PSA_SUCCESS) {
psa_pake_abort(operation);
}
unlock_status = psa_unregister_read(slot);
return (status == PSA_SUCCESS) ? unlock_status : status;
}
psa_status_t psa_pake_set_user(
psa_pake_operation_t *operation,
const uint8_t *user_id,
size_t user_id_len)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->stage != PSA_PAKE_OPERATION_STAGE_COLLECT_INPUTS) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (user_id_len == 0) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
if (operation->data.inputs.user_len != 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
operation->data.inputs.user = mbedtls_calloc(1, user_id_len);
if (operation->data.inputs.user == NULL) {
status = PSA_ERROR_INSUFFICIENT_MEMORY;
goto exit;
}
memcpy(operation->data.inputs.user, user_id, user_id_len);
operation->data.inputs.user_len = user_id_len;
return PSA_SUCCESS;
exit:
psa_pake_abort(operation);
return status;
}
psa_status_t psa_pake_set_peer(
psa_pake_operation_t *operation,
const uint8_t *peer_id,
size_t peer_id_len)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->stage != PSA_PAKE_OPERATION_STAGE_COLLECT_INPUTS) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (peer_id_len == 0) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
if (operation->data.inputs.peer_len != 0) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
operation->data.inputs.peer = mbedtls_calloc(1, peer_id_len);
if (operation->data.inputs.peer == NULL) {
status = PSA_ERROR_INSUFFICIENT_MEMORY;
goto exit;
}
memcpy(operation->data.inputs.peer, peer_id, peer_id_len);
operation->data.inputs.peer_len = peer_id_len;
return PSA_SUCCESS;
exit:
psa_pake_abort(operation);
return status;
}
psa_status_t psa_pake_set_role(
psa_pake_operation_t *operation,
psa_pake_role_t role)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
if (operation->stage != PSA_PAKE_OPERATION_STAGE_COLLECT_INPUTS) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
switch (operation->alg) {
#if defined(PSA_WANT_ALG_JPAKE)
case PSA_ALG_JPAKE:
if (role == PSA_PAKE_ROLE_NONE) {
return PSA_SUCCESS;
}
status = PSA_ERROR_INVALID_ARGUMENT;
break;
#endif
default:
(void) role;
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
exit:
psa_pake_abort(operation);
return status;
}
/* Auxiliary function to convert core computation stage to single driver step. */
#if defined(PSA_WANT_ALG_JPAKE)
static psa_crypto_driver_pake_step_t convert_jpake_computation_stage_to_driver_step(
psa_jpake_computation_stage_t *stage)
{
psa_crypto_driver_pake_step_t key_share_step;
if (stage->round == PSA_JPAKE_FIRST) {
int is_x1;
if (stage->io_mode == PSA_JPAKE_OUTPUT) {
is_x1 = (stage->outputs < 1);
} else {
is_x1 = (stage->inputs < 1);
}
key_share_step = is_x1 ?
PSA_JPAKE_X1_STEP_KEY_SHARE :
PSA_JPAKE_X2_STEP_KEY_SHARE;
} else if (stage->round == PSA_JPAKE_SECOND) {
key_share_step = (stage->io_mode == PSA_JPAKE_OUTPUT) ?
PSA_JPAKE_X2S_STEP_KEY_SHARE :
PSA_JPAKE_X4S_STEP_KEY_SHARE;
} else {
return PSA_JPAKE_STEP_INVALID;
}
return (psa_crypto_driver_pake_step_t) (key_share_step + stage->step - PSA_PAKE_STEP_KEY_SHARE);
}
#endif /* PSA_WANT_ALG_JPAKE */
static psa_status_t psa_pake_complete_inputs(
psa_pake_operation_t *operation)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
/* Create copy of the inputs on stack as inputs share memory
with the driver context which will be setup by the driver. */
psa_crypto_driver_pake_inputs_t inputs = operation->data.inputs;
if (inputs.password_len == 0) {
return PSA_ERROR_BAD_STATE;
}
if (operation->alg == PSA_ALG_JPAKE) {
if (inputs.user_len == 0 || inputs.peer_len == 0) {
return PSA_ERROR_BAD_STATE;
}
}
/* Clear driver context */
mbedtls_platform_zeroize(&operation->data, sizeof(operation->data));
status = psa_driver_wrapper_pake_setup(operation, &inputs);
/* Driver is responsible for creating its own copy of the password. */
mbedtls_zeroize_and_free(inputs.password, inputs.password_len);
/* User and peer are translated to role. */
mbedtls_free(inputs.user);
mbedtls_free(inputs.peer);
if (status == PSA_SUCCESS) {
#if defined(PSA_WANT_ALG_JPAKE)
if (operation->alg == PSA_ALG_JPAKE) {
operation->stage = PSA_PAKE_OPERATION_STAGE_COMPUTATION;
} else
#endif /* PSA_WANT_ALG_JPAKE */
{
status = PSA_ERROR_NOT_SUPPORTED;
}
}
return status;
}
#if defined(PSA_WANT_ALG_JPAKE)
static psa_status_t psa_jpake_prologue(
psa_pake_operation_t *operation,
psa_pake_step_t step,
psa_jpake_io_mode_t io_mode)
{
if (step != PSA_PAKE_STEP_KEY_SHARE &&
step != PSA_PAKE_STEP_ZK_PUBLIC &&
step != PSA_PAKE_STEP_ZK_PROOF) {
return PSA_ERROR_INVALID_ARGUMENT;
}
psa_jpake_computation_stage_t *computation_stage =
&operation->computation_stage.jpake;
if (computation_stage->round != PSA_JPAKE_FIRST &&
computation_stage->round != PSA_JPAKE_SECOND) {
return PSA_ERROR_BAD_STATE;
}
/* Check that the step we are given is the one we were expecting */
if (step != computation_stage->step) {
return PSA_ERROR_BAD_STATE;
}
if (step == PSA_PAKE_STEP_KEY_SHARE &&
computation_stage->inputs == 0 &&
computation_stage->outputs == 0) {
/* Start of the round, so function decides whether we are inputting
* or outputting */
computation_stage->io_mode = io_mode;
} else if (computation_stage->io_mode != io_mode) {
/* Middle of the round so the mode we are in must match the function
* called by the user */
return PSA_ERROR_BAD_STATE;
}
return PSA_SUCCESS;
}
static psa_status_t psa_jpake_epilogue(
psa_pake_operation_t *operation,
psa_jpake_io_mode_t io_mode)
{
psa_jpake_computation_stage_t *stage =
&operation->computation_stage.jpake;
if (stage->step == PSA_PAKE_STEP_ZK_PROOF) {
/* End of an input/output */
if (io_mode == PSA_JPAKE_INPUT) {
stage->inputs++;
if (stage->inputs == PSA_JPAKE_EXPECTED_INPUTS(stage->round)) {
stage->io_mode = PSA_JPAKE_OUTPUT;
}
}
if (io_mode == PSA_JPAKE_OUTPUT) {
stage->outputs++;
if (stage->outputs == PSA_JPAKE_EXPECTED_OUTPUTS(stage->round)) {
stage->io_mode = PSA_JPAKE_INPUT;
}
}
if (stage->inputs == PSA_JPAKE_EXPECTED_INPUTS(stage->round) &&
stage->outputs == PSA_JPAKE_EXPECTED_OUTPUTS(stage->round)) {
/* End of a round, move to the next round */
stage->inputs = 0;
stage->outputs = 0;
stage->round++;
}
stage->step = PSA_PAKE_STEP_KEY_SHARE;
} else {
stage->step++;
}
return PSA_SUCCESS;
}
#endif /* PSA_WANT_ALG_JPAKE */
psa_status_t psa_pake_output(
psa_pake_operation_t *operation,
psa_pake_step_t step,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_crypto_driver_pake_step_t driver_step = PSA_JPAKE_STEP_INVALID;
*output_length = 0;
if (operation->stage == PSA_PAKE_OPERATION_STAGE_COLLECT_INPUTS) {
status = psa_pake_complete_inputs(operation);
if (status != PSA_SUCCESS) {
goto exit;
}
}
if (operation->stage != PSA_PAKE_OPERATION_STAGE_COMPUTATION) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (output_size == 0) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
switch (operation->alg) {
#if defined(PSA_WANT_ALG_JPAKE)
case PSA_ALG_JPAKE:
status = psa_jpake_prologue(operation, step, PSA_JPAKE_OUTPUT);
if (status != PSA_SUCCESS) {
goto exit;
}
driver_step = convert_jpake_computation_stage_to_driver_step(
&operation->computation_stage.jpake);
break;
#endif /* PSA_WANT_ALG_JPAKE */
default:
(void) step;
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
status = psa_driver_wrapper_pake_output(operation, driver_step,
output, output_size, output_length);
if (status != PSA_SUCCESS) {
goto exit;
}
switch (operation->alg) {
#if defined(PSA_WANT_ALG_JPAKE)
case PSA_ALG_JPAKE:
status = psa_jpake_epilogue(operation, PSA_JPAKE_OUTPUT);
if (status != PSA_SUCCESS) {
goto exit;
}
break;
#endif /* PSA_WANT_ALG_JPAKE */
default:
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
return PSA_SUCCESS;
exit:
psa_pake_abort(operation);
return status;
}
psa_status_t psa_pake_input(
psa_pake_operation_t *operation,
psa_pake_step_t step,
const uint8_t *input,
size_t input_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_crypto_driver_pake_step_t driver_step = PSA_JPAKE_STEP_INVALID;
const size_t max_input_length = (size_t) PSA_PAKE_INPUT_SIZE(operation->alg,
operation->primitive,
step);
if (operation->stage == PSA_PAKE_OPERATION_STAGE_COLLECT_INPUTS) {
status = psa_pake_complete_inputs(operation);
if (status != PSA_SUCCESS) {
goto exit;
}
}
if (operation->stage != PSA_PAKE_OPERATION_STAGE_COMPUTATION) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
if (input_length == 0 || input_length > max_input_length) {
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
switch (operation->alg) {
#if defined(PSA_WANT_ALG_JPAKE)
case PSA_ALG_JPAKE:
status = psa_jpake_prologue(operation, step, PSA_JPAKE_INPUT);
if (status != PSA_SUCCESS) {
goto exit;
}
driver_step = convert_jpake_computation_stage_to_driver_step(
&operation->computation_stage.jpake);
break;
#endif /* PSA_WANT_ALG_JPAKE */
default:
(void) step;
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
status = psa_driver_wrapper_pake_input(operation, driver_step,
input, input_length);
if (status != PSA_SUCCESS) {
goto exit;
}
switch (operation->alg) {
#if defined(PSA_WANT_ALG_JPAKE)
case PSA_ALG_JPAKE:
status = psa_jpake_epilogue(operation, PSA_JPAKE_INPUT);
if (status != PSA_SUCCESS) {
goto exit;
}
break;
#endif /* PSA_WANT_ALG_JPAKE */
default:
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
return PSA_SUCCESS;
exit:
psa_pake_abort(operation);
return status;
}
psa_status_t psa_pake_get_implicit_key(
psa_pake_operation_t *operation,
psa_key_derivation_operation_t *output)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t abort_status = PSA_ERROR_CORRUPTION_DETECTED;
uint8_t shared_key[MBEDTLS_PSA_JPAKE_BUFFER_SIZE];
size_t shared_key_len = 0;
if (operation->stage != PSA_PAKE_OPERATION_STAGE_COMPUTATION) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
#if defined(PSA_WANT_ALG_JPAKE)
if (operation->alg == PSA_ALG_JPAKE) {
psa_jpake_computation_stage_t *computation_stage =
&operation->computation_stage.jpake;
if (computation_stage->round != PSA_JPAKE_FINISHED) {
status = PSA_ERROR_BAD_STATE;
goto exit;
}
} else
#endif /* PSA_WANT_ALG_JPAKE */
{
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
status = psa_driver_wrapper_pake_get_implicit_key(operation,
shared_key,
sizeof(shared_key),
&shared_key_len);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_key_derivation_input_bytes(output,
PSA_KEY_DERIVATION_INPUT_SECRET,
shared_key,
shared_key_len);
mbedtls_platform_zeroize(shared_key, sizeof(shared_key));
exit:
abort_status = psa_pake_abort(operation);
return status == PSA_SUCCESS ? abort_status : status;
}
psa_status_t psa_pake_abort(
psa_pake_operation_t *operation)
{
psa_status_t status = PSA_SUCCESS;
if (operation->stage == PSA_PAKE_OPERATION_STAGE_COMPUTATION) {
status = psa_driver_wrapper_pake_abort(operation);
}
if (operation->stage == PSA_PAKE_OPERATION_STAGE_COLLECT_INPUTS) {
if (operation->data.inputs.password != NULL) {
mbedtls_zeroize_and_free(operation->data.inputs.password,
operation->data.inputs.password_len);
}
if (operation->data.inputs.user != NULL) {
mbedtls_free(operation->data.inputs.user);
}
if (operation->data.inputs.peer != NULL) {
mbedtls_free(operation->data.inputs.peer);
}
}
memset(operation, 0, sizeof(psa_pake_operation_t));
return status;
}
#endif /* PSA_WANT_ALG_SOME_PAKE */
#endif /* MBEDTLS_PSA_CRYPTO_C */
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