Use Secret-Hashing Technology to Resist Side-Channel Attacks Based on Round-Keys

The development of modern cryptography has not specifically prevented Side-Channel attacks at the outset. Today, the rapid growth in Side-Channel Attacks is a significant threat. This article proposes a Secret-Hashing method that improves the main drawback of the explicitly reversible AES key expansion function. Using an extra Secret-Hashing function based on round-keys of AES to generate new round-keys will break the reversibility between the original round-keys. Let the initial attack requires only the easiest one of the round-keys to be necessary for all round-keys to complete the cracking of AES’s encryption and decryption, increases the resistance of the AES algorithm to Side-Channel Attacks by 10 to 100 times. The method is compatible with the original AES algorithm and signal leakage countermeasures, and the AES encryption and decryption process do not increase any extra payload.