Patent Document ID: 20090132830
Application ID: 12091250
Patent Flag: 0

Claim One:
1. A secure processing device that performs an operation equivalent to a secure operation performed on a message using the confidential information, and that obtains a same operation result as the secure operation, the secure processing device comprising: a storage unit that stores (i) a plurality of split confidential information pieces obtained by splitting the confidential information, (ii) a first confidential information generation equation for calculating the confidential information with use of the plurality of split confidential information pieces that are input to the first confidential information generation equation as arguments, and (iii) a first secure operation procedure indicating a procedure with use of the plurality of split confidential information pieces; a combined information generation unit operable to generate a plurality of pieces of combined information, each of which is obtained by performing an operation on at least two or more pieces of the split confidential information; a first generation unit operable to generate a second confidential information generation equation that is equivalent to the first confidential information generation equation, and that takes the plurality of pieces of combined information as; a second generation unit operable to generate, based on one or more operators included in the second confidential information generation equation, a second secure operation procedure that is equivalent to the first secure operation procedure, and that takes the plurality of pieces of combined information as; and an executing unit operable to perform the second secure operation procedure on the message.