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Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>

library/psa_crypto.c

@@ -2325,43 +2325,41 @@ psa_status_t psa_import_key( const psa_key_attributes_t *attributes,
     if( status != PSA_SUCCESS )
         goto exit;
 
-    if( psa_key_lifetime_is_external( psa_get_key_lifetime( attributes ) ) )
-    {
 #if defined(MBEDTLS_PSA_CRYPTO_SE_C)
-        if( driver != NULL )
+    if( driver != NULL )
+    {
+        const psa_drv_se_t *drv = psa_get_se_driver_methods( driver );
+        /* The driver should set the number of key bits, however in
+         * case it doesn't, we initialize bits to an invalid value. */
+        size_t bits = PSA_MAX_KEY_BITS + 1;
+        if( drv->key_management == NULL ||
+            drv->key_management->p_import == NULL )
         {
-            const psa_drv_se_t *drv = psa_get_se_driver_methods( driver );
+            status = PSA_ERROR_NOT_SUPPORTED;
-            /* The driver should set the number of key bits, however in
-             * case it doesn't, we initialize bits to an invalid value. */
-            size_t bits = PSA_MAX_KEY_BITS + 1;
-            if( drv->key_management == NULL ||
-                drv->key_management->p_import == NULL )
-            {
-                status = PSA_ERROR_NOT_SUPPORTED;
-                goto exit;
-            }
-            status = drv->key_management->p_import(
-                psa_get_se_driver_context( driver ),
-                slot->data.se.slot_number, attributes, data, data_length,
-                &bits );
-            if( status != PSA_SUCCESS )
-                goto exit;
-            if( bits > PSA_MAX_KEY_BITS )
-            {
-                status = PSA_ERROR_NOT_SUPPORTED;
-                goto exit;
-            }
-            slot->attr.bits = (psa_key_bits_t) bits;
-        }
-        else
-#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
-        {
-            /* Importing a key with external lifetime through the driver wrapper
-             * interface is not yet supported. Return as if this was an invalid
-             * lifetime. */
-            status = PSA_ERROR_INVALID_ARGUMENT;
             goto exit;
         }
+        status = drv->key_management->p_import(
+            psa_get_se_driver_context( driver ),
+            slot->data.se.slot_number, attributes, data, data_length,
+            &bits );
+        if( status != PSA_SUCCESS )
+            goto exit;
+        if( bits > PSA_MAX_KEY_BITS )
+        {
+            status = PSA_ERROR_NOT_SUPPORTED;
+            goto exit;
+        }
+        slot->attr.bits = (psa_key_bits_t) bits;
+    }
+    else
+#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
+    if( psa_key_lifetime_is_external( psa_get_key_lifetime( attributes ) ) )
+    {
+        /* Importing a key with external lifetime through the driver wrapper
+         * interface is not yet supported. Return as if this was an invalid
+         * lifetime. */
+        status = PSA_ERROR_INVALID_ARGUMENT;
+        goto exit;
     }
     else
     {

library/psa_crypto_slot_management.c

@@ -247,43 +247,35 @@ static psa_status_t psa_load_persistent_key_into_slot( psa_key_slot_t *slot )
     if( status != PSA_SUCCESS )
         goto exit;
 
-    if( psa_key_lifetime_is_external( slot->attr.lifetime ) )
-    {
 #if defined(MBEDTLS_PSA_CRYPTO_SE_C)
-        const psa_drv_se_t *drv;
+    /* Special handling is required for loading keys associated with a
-        psa_drv_se_context_t *drv_context;
+     * dynamically registered SE interface. */
-        if( psa_get_se_driver( slot->attr.lifetime, &drv, &drv_context ) )
+    const psa_drv_se_t *drv;
-        {
+    psa_drv_se_context_t *drv_context;
-            psa_se_key_data_storage_t *data;
+    if( psa_get_se_driver( slot->attr.lifetime, &drv, &drv_context ) )
-            if( key_data_length != sizeof( *data ) )
-            {
-                status = PSA_ERROR_STORAGE_FAILURE;
-                goto exit;
-            }
-            data = (psa_se_key_data_storage_t *) key_data;
-            memcpy( &slot->data.se.slot_number, &data->slot_number,
-                    sizeof( slot->data.se.slot_number ) );
-        }
-        else
-#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
-        {
-            /* A key that is successfully loaded from storage with an
-             * external lifetime, but doesn't belong to an SE driver,
-             * must be a PSA driver-associated key which we can just
-             * load like an internal key. */
-            if ( key_data == NULL )
-            {
-                status = PSA_ERROR_STORAGE_FAILURE;
-                goto exit;
-            }
-
-            status = psa_copy_key_material_into_slot( slot, key_data, key_data_length );
-        }
-    }
-    else
     {
-        status = psa_copy_key_material_into_slot( slot, key_data, key_data_length );
+        psa_se_key_data_storage_t *data;
+        if( key_data_length != sizeof( *data ) )
+        {
+            status = PSA_ERROR_STORAGE_FAILURE;
+            goto exit;
+        }
+        data = (psa_se_key_data_storage_t *) key_data;
+        memcpy( &slot->data.se.slot_number, &data->slot_number,
+                sizeof( slot->data.se.slot_number ) );
+
+        status = PSA_SUCCESS;
+        goto exit;
     }
+#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
+
+    if ( key_data == NULL )
+    {
+        status = PSA_ERROR_STORAGE_FAILURE;
+        goto exit;
+    }
+
+    status = psa_copy_key_material_into_slot( slot, key_data, key_data_length );
 
 exit:
     psa_free_persistent_key_data( key_data, key_data_length );
@@ -360,31 +352,26 @@ psa_status_t psa_validate_key_location( psa_key_lifetime_t lifetime,
     if ( psa_key_lifetime_is_external( lifetime ) )
     {
 #if defined(MBEDTLS_PSA_CRYPTO_SE_C)
+        /* Check whether a driver is registered against this lifetime */
         psa_se_drv_table_entry_t *driver = psa_get_se_driver_entry( lifetime );
-        if( driver == NULL )
+        if( driver != NULL )
-        {
-#if defined(MBEDTLS_PSA_CRYPTO_DRIVERS)
-            /* Key location for external keys gets checked by the wrapper */
-            return( PSA_SUCCESS );
-#else
-            return( PSA_ERROR_INVALID_ARGUMENT );
-#endif
-        }
-        else
         {
             if (p_drv != NULL)
                 *p_drv = driver;
             return( PSA_SUCCESS );
         }
-#else
+#else /* MBEDTLS_PSA_CRYPTO_SE_C */
         (void) p_drv;
+#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
+
 #if defined(MBEDTLS_PSA_CRYPTO_DRIVERS)
         /* Key location for external keys gets checked by the wrapper */
         return( PSA_SUCCESS );
-#else
+#else /* MBEDTLS_PSA_CRYPTO_DRIVERS */
+        /* No support for external lifetimes at all, or dynamic interface
+         * did not find driver for requested lifetime. */
         return( PSA_ERROR_INVALID_ARGUMENT );
-#endif
+#endif /* MBEDTLS_PSA_CRYPTO_DRIVERS */
-#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
     }
     else
         /* Local/internal keys are always valid */