A new security proof for Damgård's ElGamal
نویسنده
چکیده
We provide a new security proof for a variant of ElGamal proposed by Damg̊ard, showing that it is secure against non-adaptive chosen ciphertext. Unlike previous security proofs for this cryptosystem, which rely on somewhat problematic assumptions, our computational problem is similar to accepted problems such the Gap and Decision Diffie-Hellman problems.
منابع مشابه
A CCA Secure Hybrid Damgård's ElGamal Encryption
ElGamal encryption, by its efficiency, is one of the most used schemes in cryptographic applications. However, the original ElGamal scheme is only provably secure against passive attacks. Damg̊ard proposed a slight modification of ElGamal encryption scheme (named Damg̊ard’s ElGamal scheme) that provides security against non-adaptive chosen ciphertext attacks under a knowledge-of-exponent assumpti...
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عنوان ژورنال:
- IACR Cryptology ePrint Archive
دوره 2004 شماره
صفحات -
تاریخ انتشار 2004