Method and cryptographic apparatus for message scheduling and message digesting based sha algorithm

PURPOSE: A message schedule algorithmic method of the SHA(Secure Hash Algorithm) algorithm base, and the message compression algorithmic method and encryption devices for implementing the same reduces the circuit size and power consumption of the message compression part by forming the message compression part into the adder one. CONSTITUTION: A message schedule part(103) comprises one adder. The message schedule part outputs partial data among operation data previously inputted the first round to each round much intermediate data. The message schedule part is proceed the first of the SHA algorithm, the second, and the third and fourth operating functions about the first, the second, and the third and fourth intermediate data by using adder from the first round.