Encryption device, encryption method, decryption device, and decryption method

[Problem] To ensure strong security in a white-box model without the use of random numbers. [Solution] This encryption device is provided with: an encryption unit which encrypts input values by means of a black-box model, in which input and output values can be recognized from the outside and intermediate values cannot be recognized from the outside; and a key generation unit which encrypts input values of the encryption unit by means of a white-box model, in which input and output values and intermediate values can be recognized from the outside, and generates an encryption key of the encryption unit.