Secure Data Deletion from Persistent Media

Abstract

This chapter presents a general approach to the design and analysis of secure deletion for persistent storage that relies on encryption and key wrapping. It defines a key disclosure graph that models the adversarial knowledge over a history of key generation and wrapping. We define a generic update function, expressed as a graph mutation for the key disclosure graph, and prove that this update function achieves secure deletion. Instances of the update function implement the update behaviour of all tree-like data structures including B-Trees, extendible hash tables, linked lists, and others.