GIT-CERCS-09-05
David Bauer, Douglas M. Blough,
Analysis of a Redactable Signature Scheme on Data with Dependencies
Storage of personal information by service providers risks privacy
loss from data breaches. Our prior work on minimal disclosure credentials
presented a mechanism to limit the amount of personal
information provided. In that work, personal data was broken into
individual claims, which can be released in arbitrary subsets while still being
cryptographically verifiable. In applying that work, we encountered the
problem of connections between claims, which manifest as disclosure dependencies.
In further prior work, we provide an efficient way to provide
minimal disclosure, but with cryptographic enforcement of dependencies between
claims, as specified by the claims certifier. Now, this work provides security proofs showing that the scheme is secure against forgery and the violation of dependencies in the random oracle model. Additional motivation is provided for a preservation of privacy and security in the standard model.