HASH VALUE GENERATING METHOD, DATA CIPHERING METHOD, DATA DECIPHERING METHOD, HASH VALUE GENERATING DEVICE DATA CIPHERING DEVICE, AND DATA DECIPHERING DEVICE

摘要

PROBLEM TO BE SOLVED: To disorder data efficiently by performing a multiplying process which makes the length of an output value longer than that of an input value in a hash value generating process. ;SOLUTION: Expanded data 107 generated by a data expansion part 102 are divided into 64-bit frames (group of blocks) like a 1st section E₁ 108, a 2nd section E₂ 109... and inputted to a single-shot expansion part 105 in order. The single-shot expansion part 105 performs a single-shot expanding process for the 1st section E₁ 108 by using a 256-bit initial value 110 as a parameter while performing conversion and transposition. For the 2nd section E₂ 109, a single-shot expanding process is performed by using a 1st 256-bit intermediate output which is obtained while conversion and transposition are carried out. Consequently, a 2nd 256-bit intermediate output is calculated. This process is repeated until the frame of the final section is inputted and then the 256-bit intermediate output which is calculated finally is used as a hash value Hash 111.;COPYRIGHT: (C)1998,JPO