Security of Digital Signature Schemes in Weakened Random Oracle Models
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چکیده
We formalize the notion of several weakened random oracle models in order to capture which property of a hash function is crucial to prove the security of a cryptographic scheme. In particular, we focus on augmenting the random oracle with additional oracles that respectively return collisions, secondpreimages, and first-preimages. We study the security of the full domain hash signature scheme, as well as three variants thereof in the weakened random oracle models, leading to a separation result.
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تاریخ انتشار 2008