Hiraku MORITA


Constant-Round Client-Aided Two-Server Secure Comparison Protocol and Its Applications
Hiraku MORITA Nuttapong ATTRAPADUNG Tadanori TERUYA Satsuya OHATA Koji NUIDA Goichiro HANAOKA 
Publication:   
Publication Date: 2020/01/01
Vol. E103-A  No. 1  pp. 21-32
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
multi-party computationclient-server modelclient-aided methodless-than comparisonconstant roundsGMW secret sharing
 Summary | Full Text:PDF(2MB)

On the Security of Non-Interactive Key Exchange against Related-Key Attacks
Hiraku MORITA Jacob C.N. SCHULDT Takahiro MATSUDA Goichiro HANAOKA Tetsu IWATA 
Publication:   
Publication Date: 2017/09/01
Vol. E100-A  No. 9  pp. 1910-1923
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
related-key attacksNon-Interactive Key ExchangeDiffie-Hellman key exchange scheme
 Summary | Full Text:PDF(1.1MB)

On the Security of Schnorr Signatures, DSA, and ElGamal Signatures against Related-Key Attacks
Hiraku MORITA Jacob C.N. SCHULDT Takahiro MATSUDA Goichiro HANAOKA Tetsu IWATA 
Publication:   
Publication Date: 2017/01/01
Vol. E100-A  No. 1  pp. 73-90
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
related-key attacksSchnorr signaturesDSAElGamal signatures.
 Summary | Full Text:PDF(540KB)