Almost Tightly-Secure Re-Randomizable and Replayable CCA-secure Public Key Encryption

ePrint Report: Almost Tightly-Secure Re-Randomizable and Replayable CCA-secure Public Key Encryption

Antonio Faonio, Dennis Hofheinz, Luigi Russo

Re-randomizable Replayable CCA-secure public key encryption (Rand-RCCA PKE) schemes guarantee security against chosen-ciphertext attacks while ensuring the useful property of re-randomizable ciphertexts. We introduce the notion of multi-user and multi-ciphertext Rand-RCCA PKE and we give the first construction of such a PKE scheme with an almost tight security reduction to a standard assumption. Our construction is structure preserving and can be instantiated over …

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