Restructure cipher context object to contain driver switch
Once an operation has been 'accepted' by a driver, the remainder is bound
to the same driver, since driver-specific context structs cannot be shared.
This provides a pretty good gate mechanism for the fallback logic, too.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
diff --git a/include/psa/crypto_struct.h b/include/psa/crypto_struct.h
index 0ea8073..3ff3f93 100644
--- a/include/psa/crypto_struct.h
+++ b/include/psa/crypto_struct.h
@@ -158,6 +158,7 @@
unsigned int key_set : 1;
unsigned int iv_required : 1;
unsigned int iv_set : 1;
+ unsigned int accelerator_set : 1;
uint8_t iv_size;
uint8_t block_size;
union
@@ -173,7 +174,7 @@
} ctx;
};
-#define PSA_CIPHER_OPERATION_INIT {0, 0, 0, 0, 0, 0, {0}}
+#define PSA_CIPHER_OPERATION_INIT {0, 0, 0, 0, 0, 0, 0, {0}}
static inline struct psa_cipher_operation_s psa_cipher_operation_init( void )
{
const struct psa_cipher_operation_s v = PSA_CIPHER_OPERATION_INIT;
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 6acf498..7eb9568 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -4059,9 +4059,9 @@
{
operation->iv_required = 1;
}
+ operation->accelerator_set = 0;
operation->iv_size = 0;
operation->block_size = 0;
- mbedtls_cipher_init( &operation->ctx.cipher );
return( PSA_SUCCESS );
}
@@ -4083,6 +4083,14 @@
if( status != PSA_SUCCESS )
goto exit;
+ /* A context must be freshly initialized before it can be set up. */
+ if( operation->alg != 0 )
+ return( PSA_ERROR_BAD_STATE );
+
+ status = psa_cipher_init( operation, alg );
+ if( status != PSA_SUCCESS )
+ return( status );
+
/* Try doing this through a driver before using software fallback */
if( cipher_operation == MBEDTLS_ENCRYPT )
status = psa_driver_wrapper_cipher_encrypt_setup( operation,
@@ -4093,18 +4101,19 @@
slot,
alg );
- if( status != PSA_ERROR_NOT_SUPPORTED )
- goto exit;
-
- /* A context must be freshly initialized before it can be set up. */
- if( operation->alg != 0 )
+ if( status == PSA_SUCCESS )
{
- return( PSA_ERROR_BAD_STATE );
+ operation->accelerator_set = 1;
+ operation->key_set = 1;
}
- status = psa_cipher_init( operation, alg );
- if( status != PSA_SUCCESS )
- return( status );
+ if( status != PSA_ERROR_NOT_SUPPORTED ||
+ psa_key_lifetime_is_external( slot->attr.lifetime ) )
+ goto exit;
+
+ /* Proceed with initializing mbed TLS cipher context if no accelerator is
+ * available for the given algorithm & key. */
+ mbedtls_cipher_init( &operation->ctx.cipher );
status = psa_get_transparent_key( handle, &slot, usage, alg);
if( status != PSA_SUCCESS )
@@ -4206,7 +4215,14 @@
{
psa_status_t status;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- if( operation->iv_set || ! operation->iv_required )
+
+ if( operation->accelerator_set == 1 )
+ return( psa_driver_wrapper_cipher_generate_iv( operation,
+ iv,
+ iv_size,
+ iv_length ) );
+
+ if( operation->iv_set || ! operation->iv_required || ! operation->key_set )
{
return( PSA_ERROR_BAD_STATE );
}
@@ -4238,7 +4254,13 @@
{
psa_status_t status;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- if( operation->iv_set || ! operation->iv_required )
+
+ if( operation->accelerator_set == 1 )
+ return( psa_driver_wrapper_cipher_set_iv( operation,
+ iv,
+ iv_length ) );
+
+ if( operation->iv_set || ! operation->iv_required || ! operation->key_set )
{
return( PSA_ERROR_BAD_STATE );
}
@@ -4355,7 +4377,15 @@
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t expected_output_size;
- if( operation->alg == 0 )
+ if( operation->accelerator_set == 1 )
+ return( psa_driver_wrapper_cipher_update( operation,
+ input,
+ input_length,
+ output,
+ output_size,
+ output_length ) );
+
+ if( operation->alg == 0 || ! operation->key_set )
{
return( PSA_ERROR_BAD_STATE );
}
@@ -4414,6 +4444,12 @@
int cipher_ret = MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
uint8_t temp_output_buffer[MBEDTLS_MAX_BLOCK_LENGTH];
+ if( operation->accelerator_set == 1 )
+ return( psa_driver_wrapper_cipher_finish( operation,
+ output,
+ output_size,
+ output_length ) );
+
if( ! operation->key_set )
{
return( PSA_ERROR_BAD_STATE );
@@ -4483,11 +4519,15 @@
if( ! PSA_ALG_IS_CIPHER( operation->alg ) )
return( PSA_ERROR_BAD_STATE );
- mbedtls_cipher_free( &operation->ctx.cipher );
+ if( operation->accelerator_set == 1 )
+ psa_driver_wrapper_cipher_abort( operation );
+ else
+ mbedtls_cipher_free( &operation->ctx.cipher );
operation->alg = 0;
operation->key_set = 0;
operation->iv_set = 0;
+ operation->accelerator_set = 0;
operation->iv_size = 0;
operation->block_size = 0;
operation->iv_required = 0;
diff --git a/tests/src/drivers/cipher.c b/tests/src/drivers/cipher.c
index 0f059a0..9db5061 100644
--- a/tests/src/drivers/cipher.c
+++ b/tests/src/drivers/cipher.c
@@ -40,6 +40,8 @@
void *test_driver_cipher_forced_output = NULL;
size_t test_driver_cipher_forced_output_length = 0;
+/* Test driver, if not explicitly setup, returns 'PSA_ERROR_NOT_SUPPORTED' by default,
+ * causing regular test suites to pass since the core will go into fallback mode. */
psa_status_t test_transparent_cipher_status = PSA_ERROR_NOT_SUPPORTED;
unsigned long test_transparent_cipher_hit = 0;