Electronic apparatus using homomorphic cipher and method thereof

Abstract

An electronic apparatus is disclosed. The electronic apparatus includes a memory configured to store a homomorphic ciphertext including a tag and a program operating in the electronic apparatus, a user interface, and a processor, and the tag includes type information for original data of the homomorphic ciphertext, and is set, based on computation for the homomorphic ciphertext being performed, such that the tag included in the homomorphic ciphertext used in the computation is included in even a computation result value generated by the computation being performed, and the processor is configured to generate, based on receiving a computation request for the homomorphic ciphertext from the program, a computation result value by performing computation for the homomorphic ciphertext, check the type information for the original data of the homomorphic ciphertext used in the computation based on the tag included in the computation result value, perform decryption of the computation result value, control the user interface to display the checked type information for the original data and the decrypted computation result value, and provide, based on receiving a command to provide data through the user interface, the decrypted computation result value to the program.