Trapdooring Discrete Logarithms on Elliptic Curves over Rings

This paper introduces three new probabilistic encryption schemes using elliptic curves over rings. The cryptosystems are based on three specific trapdoor mechanisms allowing the recipient to recover discrete logarithms on different types of curves. The first scheme is an embodiment of Naccache and Stern’s cryptosystem and realizes a discrete log encryption as originally wanted in [23] by Vanstone and Zuccherato. Our second scheme provides an elliptic curve version of Okamoto and Uchiyama’s probabilistic encryption, thus answering a question left open in [10] by the same authors. Finally, we introduce a Paillier-like encryption scheme based on the use of twists of anomalous curves. Our contributions provide probabilistic, homomorphic and semantically secure cryptosystems that concretize all previous research works on discrete log encryption in the elliptic curve setting. Keywords. Elliptic Curve Cryptosystems, Discrete Logarithm Encryption, Homomorphic Encryption, Naccache-Stern,...

• Type: Conference
• Year: 2000
• Where: ASIACRYPT
• Authors: Pascal Paillier
• Keywords: ASIACRYPT 2000, Cryptology, Discrete Log Encryption, Elliptic Curve, Probabilistic Encryption