Configurable modular multiplication method and system for finite field GF (2m)

The invention provides a configurable modular multiplication method and system for a finite field GF (2m), and belongs to the technical field of hardware information security. Comprising the following steps: S1, inputting operands A and B with the bit width of 571 bits, respectively decomposing the operands A and B into three sections of 192-bit sub-operands, calculating the addition of the sub-operands, and when the bit width is insufficient, performing high-bit zero filling; s2, decomposing the sub-operands again to obtain six groups of 32-bit sub-operands; continuously decomposing each 32-bit sub-operand to obtain 8 new 4-bit sub-operands; 48 4-bit new sub-operands are obtained, and every 8 4-bit new sub-operands form a group; s3, calculating modular multiplication partial products, wherein each group of new sub-operands corresponds to one partial product; all partial product calculation is completed in T15 cycles, and a multiplication result is obtained; and S4, reducing the multiplication result in the T