[#505] ir/container: Check key ownership in Put container handler

Check if new container was signed by its owner, and otherwise prohibit
operation.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/innerring/processors/container/process_container.go

@@ -61,7 +61,7 @@ func (cp *Processor) checkPutContainer(e *containerEvent.Put) error {
 		return fmt.Errorf("incorrect container format: %w", err)
 	}
 
-	return nil
+	return cp.checkKeyOwnership(cnr, key)
 }
 
 func (cp *Processor) approvePutContainer(e *containerEvent.Put) {