A digital evidence protection method with hierarchical access control mechanisms

摘要

Digital evidences are the important basis in digital forensic. This paper proposed a concrete digital evidence protection method with hierarchical access control mechanisms using cryptographic techniques. It allows judicial policeman to authenticated encrypt the collected digital evidences from being disclosed and modified by potential malicious attackers (including malicious insiders and outsiders). Only the authorized users can retrieve and access the digital evidences and verify their integrity. Hence, confidentiality, integrity, authenticity protection for digital evidences can be achieved. Moreover, this method also allows the judiciary bureaus to present the digital evidences together with protection proof to a trusted third party in case of a later dispute. We further considered the access control security issues in hierarchical judiciary bureaus to propose two access control mechanisms, i.e. partial and full supervision. In the partial supervision, the supervisor will given a partial privilege to access some specified digital evidences when he want to monitor and supervise the investigation progress. In the full supervision, the supervisor is given a full privilege to access all digital evidences investigated by his subordinates in a particular situation.