Redactable Signatures for Tree-Structured Data: Definitions and Constructions
نویسندگان
چکیده
Kundu and Bertino (VLDB 2008) recently introduced the idea of structural signatures for trees which support public redaction of subtrees (by third-party distributors) while pertaining the integrity of the remaining parts. An example is given by signed XML documents of which parts should be sanitized before being published by a distributor not holding the signing key. Kundu and Bertino also provide a construction, but fall short of providing formal security definitions and proofs. Here we revisit their work and give rigorous security models for the redactable signatures for tree-structured data, relate the notions, and give a construction that can be proven secure under standard cryptographic assumptions.
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