Cryptology ePrint Archive: Report 2018/845

A Framework for Achieving KDM-CCA Secure Public-Key Encryption

Fuyuki Kitagawa and Keisuke Tanaka

Abstract: We propose a framework for achieving a public-key encryption (PKE) scheme that satisfies key dependent message security against chosen ciphertext attacks (KDM-CCA security) based on projective hash function. Our framework can be instantiated under the decisional diffie-hellman (DDH), quadratic residuosity (QR), and decisional composite residuosity (DCR) assumptions. The constructed schemes are KDM-CCA secure with respect to affine functions and compatible with the amplification method shown by Applebaum (EUROCRYPT 2011). Thus, they lead to PKE schemes satisfying KDM-CCA security for all functions computable by a-priori bounded size circuits. They are the first PKE schemes satisfying such a security notion in the standard model using neither non-interactive zero knowledge proof nor bilinear pairing.

The above framework based on projective hash function captures only KDM-CCA security in the single user setting. However, we can prove the KDM-CCA security in the multi user setting of our concrete instantiations by using their algebraic structures explicitly. Especially, we prove that our DDH based scheme satisfies KDM-CCA security in the multi user setting with the same parameter setting as in the single user setting.

Category / Keywords: public-key cryptography / key dependent message security, chosen ciphertext security, projective hash function.

Original Publication (with minor differences): IACR-ASIACRYPT-2018

Date: received 7 Sep 2018

Contact author: kitagaw1 at is titech ac jp

Available format(s): PDF | BibTeX Citation

Version: 20180914:151852 (All versions of this report)

Short URL: ia.cr/2018/845


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