Information processing apparatus, information processing system and medium

An information processing apparatus that processes a plurality of encrypted text data items, the information processing apparatus comprising:

• an input unit configured to input third data and fourth data that are the encrypted text data items;
• a first memory unit configured to store a fourth table used for transforming the third data and a fifth table used for transforming the fourth data;
• a first transforming unit configured to transform the third data to third transformed data based on the fourth table;
• a second transforming unit configured to transform the fourth data to fourth transformed data based on the fifth table;
• a multiplication unit configured to calculate a multiplication result by multiplying the first transformed data by the second transformed data;
• a remainder calculation unit configured to obtain a remainder by dividing the multiplication result by an exponential number having 2 as a base and having the number of bits of the encrypted text data items as an exponent;
• a second memory unit configured to store a sixth table used for transforming the remainder;
• and
• a third transforming unit configured to output an output result by transforming the remainder based on the sixth table.

An information processing apparatus that processes a plurality of encrypted text data items, the information processing apparatus comprising:

• an input unit configured to input fifth data and sixth data that are the encrypted text data items;
• a first memory unit configured to store a seventh table used for transforming the fifth data and the sixth data;
• a first transforming unit configured to transform the fifth data to fifth transformed data based on the seventh table;
• a second transforming unit configured to transform the sixth data to sixth transformed data based on the seventh table;
• a calculation unit configured to calculate a calculation result obtained by calculating a logical AND, a logical OR, or both of the logical AND and the logical OR, of the fifth transformed data and the sixth transformed data;
• a second memory unit configured to store an eighth table used for transforming the remainder;
• and
• a third transforming unit configured to output an output result by transforming the remainder based on the eighth table.

An information processing apparatus that calculates an exclusive OR of a plurality of encrypted text data items, the information processing apparatus comprising:

• an input unit configured to input seventh data and eighth data that are the encrypted text data items;
• a first memory unit configured to store a ninth table used for transforming the seventh data and a tenth table used for transforming the eighth data;
• a first transforming unit configured to transform the seventh data to seventh transformed data based on the ninth table;
• a second transforming unit configured to transform the eighth data to eighth transformed data based on the tenth table;
• a calculation unit configured to calculate a calculation result obtained by calculating an exclusive OR of the seventh transformed data and the eighth transformed data;
• a second memory unit configured to store an eleventh table used for transforming the remainder;
• and
• a third transforming unit configured to output an output result by transforming the remainder based on the eleventh table.

A recording medium storing a program for causing a computer that processes a plurality of encrypted text data items, to perform an information processing method, the method comprising:

• inputting first data and second data that are the encrypted text data items;
• storing a first table used for transforming the first data and a second table used for transforming the second data;
• transforming the first data to first transformed data based on the first table;
• transforming the second data to second transformed data based on the second table;
• calculating an addition result by adding the first transformed data and the second transformed data;
• obtaining a remainder by dividing the addition result by an exponential number having 2 as a base and having the number of bits of the encrypted text data items as an exponent;
• storing a third table used for transforming the remainder;
• and
• outputting an output result by transforming the remainder based on the third table.

An information processing system comprising:

• an information processing apparatus for processing a plurality of encrypted text data items;
• and an output terminal connected to the information processing apparatus, wherein
• the information processing apparatus includes
• an input unit configured to input first data and second data that are the encrypted text data items;
• a first memory unit configured to store a first table used for transforming the first data and a second table used for transforming the second data;
• a first transforming unit configured to transform the first data to first transformed data based on the first table;
• a second transforming unit configured to transform the second data to second transformed data based on the second table;
• an addition unit configured to calculate an addition result by adding the first transformed data and the second transformed data;
• a remainder calculation unit configured to obtain a remainder by dividing the addition result by an exponential number having 2 as a base and having the number of bits of the encrypted text data items as an exponent;
• a second memory unit configured to store a third table used for transforming the remainder;
• and
• a third transforming unit configured to output an output result by transforming the remainder based on the third table, and
• the output terminal includes
• a decryption unit configured to decrypt the output result.