Claims
- 1. An encrypting conversion apparatus for inputting at least one cipher key, at least one algorithm parameter which is independent of said cipher key, and plain text data and outputting cipher text data, said encrypting apparatus comprising:a plurality stage of encrypting conversion means for executing each of an exclusive logical sum operation, a cyclic shift operation and an addition operation at least once, wherein: said encrypting conversion means includes at least one of each of first to third operation means, said first operation means executes either an exclusive logical sum operation or an addition operation of input data and a portion of data generated from data of the cipher key, said second operation means executes either an exclusive logical sum operation or an addition operation of input data and a determined by a portion of said algorithm parameter, and said third operation means cyclically shifts input data by the number of bits determined dynamically based on a portion of said algorithm parameter; and conversions which use combinations of a plurality stage of consecutive encrypting conversion means optionally selected from all of said encrypting conversion means and use the same input data and the same algorithm parameter, are all different.
- 2. A decrypting conversion apparatus for inputting at least one cipher key, at least one an algorithm parameter which is independent of said cipher key, and cipher text data and outputting plain text data, the apparatus comprising:a plurality stage of decrypting conversion means for executing each of an exclusive logical sum operation, a cyclic shift operation and an addition operation at least once, wherein: said decrypting conversion means includes at least one of each of first to third operation means, said first operation means executes either an exclusive logical sum operation or an addition operation of input data and a portion of data generated from data of the cipher key, said second operation means executes either an exclusive logical sum operation or an addition operation of input data and a determined by a portion of said algorithm parameter, and said third operation means cyclically shifts input data by the number of bits determined dynamically based on a portion of said algorithm parameter; and conversions which use combinations of a plurality stage of consecutive decrypting conversion means optionally selected from all of said decrypting conversion means and use the same input data and the same algorithm parameter, are all different.
Priority Claims (1)
Number |
Date |
Country |
Kind |
10-148712 |
May 1998 |
JP |
|
CROSS-REFERENCE TO RELATED APPLICATION
This application relates to an application U.S. Ser. No. 09/130,529 filed on Aug. 4, 1998 by Makoto Aikawa et al entitled “DATA ENCRYPTING/DECRYPTING CONVERSION METHODS AND APPARATUSES AND DATA COMMUNICATION SYSTEM ADOPTING THE SAME” and assigned to the present assignee. The disclosure of that application is hereby incorporated by reference into the disclosure of this application.
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