The invention discloses a multiplying unit on a finite field GF (2 227) and a modular multiplication
algorithm, and belongs to the technical field of the
encryption and decryption of
data information. The multiplying unit comprises a
partial product overlapping module, a first register, a first accumulation module, a second register, a second accumulation module, a third register, a modular addition module and a fourth register. A multiply operation unit 227*57 is reused by the modular multiplication
algorithm, a modular multiplication module of which m is equal to 227 applied to an ECC (
Elliptic Curve Cryptography)
system of which the bit width m is equal to 226 is provided; when m is equal to 226, an AOP (All One Polynomial) type reduction polynomial is generated, and the redundant of an
operand is represented by a formula that m is equal to 227, therefore the reduction polynomial can be simplified, and the modular multiplication performance can be improved; furthermore, the registers are inserted into the
partial product overlapping part, and a path for modular multiplication can be
cut off, therefore the length of a critical path can be reduced, the modular multiplication can be executed in a streamline way, the
clock frequency can be improved, the
processing speed and data throughout can be improved, and
resource saving can be realized.