• 정보보호학회논문지
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• 제24권3호
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• pp.461-475
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• 2014

준동형 MAC은 데이터의 무결성을 보호하면서도 제 3자에 의한 데이터 처리를 허용하는 암호학적 개념이다. 본 논문에서는 새로운 준동형 MAC을 제시하고 그 안전성을 증명하도록 한다. 본 논문의 MAC은 정수에 기반하고 있고, 단지 안전한 PRF의 존재성만을 가정하며, 실용적인 Catalano-Fiore 준동형 MAC과 비견할 만한 효율성을 갖는다. 본 방식은 공격자가 MAC 검증 질의를 할 수 있는 환경에서도 위조 불가능하며, 이 안전성은 강한 위조 불가능성을 보이는 방법으로 증명되었다.

• ETRI Journal
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• 제35권1호
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• pp.173-176
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• 2013

Existing symmetric cryptography-based solutions against pollution attacks for network coding systems suffer various drawbacks, such as highly complicated key distribution and vulnerable security against collusion. This letter presents a novel homomorphic subspace message authentication code (MAC) scheme that can thwart pollution attacks in an efficient way. The basic idea is to exploit the combination of the symmetric cryptography and linear subspace properties of network coding. The proposed scheme can tolerate the compromise of up to r-1 intermediate nodes when r source keys are used. Compared to previous MAC solutions, less secret keys are needed for the source and only one secret key is distributed to each intermediate node.

• Journal of Information Processing Systems
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• 제16권3호
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• pp.599-611
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• 2020

With the application and promotion of biometric technology, biometrics has become more and more important to identity authentication. In order to ensure the privacy of the user, the biometrics cannot be stored or manipulated in plaintext. Aiming at this problem, this paper analyzes and summarizes the scheme and performance of the existing biometric authentication system, and proposes an iris-based ciphertext authentication system based on fully homomorphic encryption using the FV scheme. The implementation of the system is partly powered by Microsoft's SEAL (Simple Encrypted Arithmetic Library). The entire system can complete iris authentication without decrypting the iris feature template, and the database stores the homomorphic ciphertext of the iris feature template. Thus, there is no need to worry about the leakage of the iris feature template. At the same time, the system does not require a trusted center for authentication, and the authentication is completed on the server side directly using the one-time MAC authentication method. Tests have shown that when the system adopts an iris algorithm with a low depth of calculation circuit such as the Hamming distance comparison algorithm, it has good performance, which basically meets the requirements of real application scenarios.