psa: aead: Isolate key slot unlock from operation abort
As we want to do Mbed TLS aead operations as a
driver does, aead operations should not access
the key slot as key slots are not available to
drivers.
Second step in this PR: do not unlock the key slot
as part of operation abort.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index b135b72..70d3d5e 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -3559,8 +3559,6 @@
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
}
-
- psa_unlock_key_slot( operation->slot );
}
static psa_status_t psa_aead_setup( aead_operation_t *operation,
@@ -3576,10 +3574,7 @@
mbedtls_cipher_info_from_psa( alg, operation->slot->attr.type, key_bits,
&cipher_id );
if( operation->cipher_info == NULL )
- {
- status = PSA_ERROR_NOT_SUPPORTED;
- goto cleanup;
- }
+ return( PSA_ERROR_NOT_SUPPORTED );
switch( PSA_ALG_AEAD_WITH_SHORTENED_TAG( alg, 0 ) )
{
@@ -3591,17 +3586,15 @@
* The call to mbedtls_ccm_encrypt_and_tag or
* mbedtls_ccm_auth_decrypt will validate the tag length. */
if( PSA_BLOCK_CIPHER_BLOCK_LENGTH( operation->slot->attr.type ) != 16 )
- {
- status = PSA_ERROR_INVALID_ARGUMENT;
- goto cleanup;
- }
+ return( PSA_ERROR_INVALID_ARGUMENT );
+
mbedtls_ccm_init( &operation->ctx.ccm );
status = mbedtls_to_psa_error(
mbedtls_ccm_setkey( &operation->ctx.ccm, cipher_id,
operation->slot->key.data,
(unsigned int) key_bits ) );
- if( status != 0 )
- goto cleanup;
+ if( status != PSA_SUCCESS )
+ return( status );
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
@@ -3613,17 +3606,15 @@
* The call to mbedtls_gcm_crypt_and_tag or
* mbedtls_gcm_auth_decrypt will validate the tag length. */
if( PSA_BLOCK_CIPHER_BLOCK_LENGTH( operation->slot->attr.type ) != 16 )
- {
- status = PSA_ERROR_INVALID_ARGUMENT;
- goto cleanup;
- }
+ return( PSA_ERROR_INVALID_ARGUMENT );
+
mbedtls_gcm_init( &operation->ctx.gcm );
status = mbedtls_to_psa_error(
mbedtls_gcm_setkey( &operation->ctx.gcm, cipher_id,
operation->slot->key.data,
(unsigned int) key_bits ) );
- if( status != 0 )
- goto cleanup;
+ if( status != PSA_SUCCESS )
+ return( status );
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
@@ -3633,36 +3624,27 @@
operation->full_tag_length = 16;
/* We only support the default tag length. */
if( alg != PSA_ALG_CHACHA20_POLY1305 )
- {
- status = PSA_ERROR_NOT_SUPPORTED;
- goto cleanup;
- }
+ return( PSA_ERROR_NOT_SUPPORTED );
+
mbedtls_chachapoly_init( &operation->ctx.chachapoly );
status = mbedtls_to_psa_error(
mbedtls_chachapoly_setkey( &operation->ctx.chachapoly,
operation->slot->key.data ) );
- if( status != 0 )
- goto cleanup;
+ if( status != PSA_SUCCESS )
+ return( status );
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
default:
- status = PSA_ERROR_NOT_SUPPORTED;
- goto cleanup;
+ return( PSA_ERROR_NOT_SUPPORTED );
}
if( PSA_AEAD_TAG_LENGTH( alg ) > operation->full_tag_length )
- {
- status = PSA_ERROR_INVALID_ARGUMENT;
- goto cleanup;
- }
+ return( PSA_ERROR_INVALID_ARGUMENT );
+
operation->tag_length = PSA_AEAD_TAG_LENGTH( alg );
return( PSA_SUCCESS );
-
-cleanup:
- psa_aead_abort_internal( operation );
- return( status );
}
psa_status_t psa_aead_encrypt( mbedtls_svc_key_id_t key,
@@ -3690,7 +3672,7 @@
status = psa_aead_setup( &operation, alg );
if( status != PSA_SUCCESS )
- return( status );
+ goto exit;
/* For all currently supported modes, the tag is at the end of the
* ciphertext. */
@@ -3758,7 +3740,10 @@
memset( ciphertext, 0, ciphertext_size );
exit:
+ psa_unlock_key_slot( operation.slot );
psa_aead_abort_internal( &operation );
+
+
if( status == PSA_SUCCESS )
*ciphertext_length = plaintext_length + operation.tag_length;
return( status );
@@ -3810,7 +3795,7 @@
status = psa_aead_setup( &operation, alg );
if( status != PSA_SUCCESS )
- return( status );
+ goto exit;
status = psa_aead_unpadded_locate_tag( operation.tag_length,
ciphertext, ciphertext_length,
@@ -3874,7 +3859,9 @@
memset( plaintext, 0, plaintext_size );
exit:
+ psa_unlock_key_slot( operation.slot );
psa_aead_abort_internal( &operation );
+
if( status == PSA_SUCCESS )
*plaintext_length = ciphertext_length - operation.tag_length;
return( status );