SHA256哈希算法verilog

以下是SHA256哈希算法的Verilog实现示例：

module SHA256(
    input clk,
    input [511:0] message,
    output [255:0] hash
);

reg [31:0] H[7];
reg [31:0] W[63];
reg [31:0] a,b,c,d,e,f,g,h;
reg [31:0] temp1,temp2;
reg [31:0] S0,S1;
reg [31:0] ch,maj;

assign hash = {H[0],H[1],H[2],H[3],H[4],H[5],H[6]};

initial begin
    H[0] = 32'h6a09e667;
    H[1] = 32'hbb67ae85;
    H[2] = 32'h3c6ef372;
    H[3] = 32'ha54ff53a;
    H[4] = 32'h510e527f;
    H[5] = 32'h9b05688c;
    H[6] = 32'h1f83d9ab;
end

always @(posedge clk) begin
    // Message schedule
    for (int i = 0; i < 16; i = i + 1) begin
        W[i] = message[i*32+31:i*32];
    end
    for (int i = 16; i < 64; i = i + 1) begin
        S0 = (W[i-15]>>>7) ^ (W[i-15]>>>18) ^ (W[i-15]>>3);
        S1 = (W[i-2]>>>17) ^ (W[i-2]>>>19) ^ (W[i-2]>>10);
        W[i] = W[i-16] + S0 + W[i-7] + S1;
    end

    // Compression
    a = H[0]; b = H[1]; c = H[2]; d = H[3];
    e = H[4]; f = H[5]; g = H[6]; h = 32'hbe0e27b;

    for (int i = 0; i < 64; i = i + 1) begin
        S1 = (e>>>6) ^ (e>>>11) ^ (e>>>25);
        ch = (e & f) ^ ((~e) & g);
        temp1 = h + S1 + ch + K[i] + W[i];
        S0 = (a>>>2) ^ (a>>>13) ^ (a>>>22);
        maj = (a & b) ^ (a & c) ^ (b & c);
        temp2 = S0 + maj;
        h = g; g = f; f = e; e = d + temp1; d = c; c = b; b = a; a = temp1 + temp2;
    end

    // Update hash values
    H[0] = H[0] + a; H[1] = H[1] + b; H[2] = H[2] + c; H[3] = H[3] + d;
    H[4] = H[4] + e; H[5] = H[5] + f; H[6] = H[6] + g; H[7] = H[7] + h;
end

endmodule

上述代码是一个SHA256哈希算法的简单实现，其中包含了消息扩展和压缩两个步骤。在实际应用中，需要进行更复杂的设计以提高安全性和性能。