sha1算法 verilog

以下是sha1算法的Verilog代码示例：

module sha1(
  input clk, // 时钟
  input rst, // 复位
  input [511:0] message, // 消息
  output reg [159:0] hash // 哈希值
);

reg [31:0] h0, h1, h2, h3, h4; // 初始哈希值
reg [79:0] w [0:15]; // 消息扩展字
reg [31:0] a, b, c, d, e; // 哈希值中间变量
reg [79:0] k [0:79]; // 常量

// 初始化
initial begin
  h0 = 32'h67452301;
  h1 = 32'hefcdab89;
  h2 = 32'h98badcfe;
  h3 = 32'h10325476;
  h4 = 32'hc3d2e1f0;

  k[0] = 32'h5a827999;
  k[1] = 32'h6ed9eba1;
  k[2] = 32'h8f1bbcdc;
  k[3] = 32'hca62c1d6;
  k[4] = 32'h5a827999;
  k[5] = 32'h6ed9eba1;
  k[6] = 32'h8f1bbcdc;
  k[7] = 32'hca62c1d6;
  k[8] = 32'h5a827999;
  k[9] = 32'h6ed9eba1;
  k[10] = 32'h8f1bbcdc;
  k[11] = 32'hca62c1d6;
  k[12] = 32'h5a827999;
  k[13] = 32'h6ed9eba1;
  k[14] = 32'h8f1bbcdc;
  k[15] = 32'hca62c1d6;
  k[16] = 32'h5a827999;
  k[17] = 32'h6ed9eba1;
  k[18] = 32'h8f1bbcdc;
  k[19] = 32'hca62c1d6;
  k[20] = 32'h5a827999;
  k[21] = 32'h6ed9eba1;
  k[22] = 32'h8f1bbcdc;
  k[23] = 32'hca62c1d6;
  k[24] = 32'h5a827999;
  k[25] = 32'h6ed9eba1;
  k[26] = 32'h8f1bbcdc;
  k[27] = 32'hca62c1d6;
  k[28] = 32'h5a827999;
  k[29] = 32'h6ed9eba1;
  k[30] = 32'h8f1bbcdc;
  k[31] = 32'hca62c1d6;
  k[32] = 32'h5a827999;
  k[33] = 32'h6ed9eba1;
  k[34] = 32'h8f1bbcdc;
  k[35] = 32'hca62c1d6;
  k[36] = 32'h5a827999;
  k[37] = 32'h6ed9eba1;
  k[38] = 32'h8f1bbcdc;
  k[39] = 32'hca62c1d6;
  k[40] = 32'h5a827999;
  k[41] = 32'h6ed9eba1;
  k[42] = 32'h8f1bbcdc;
  k[43] = 32'hca62c1d6;
  k[44] = 32'h5a827999;
  k[45] = 32'h6ed9eba1;
  k[46] = 32'h8f1bbcdc;
  k[47] = 32'hca62c1d6;
  k[48] = 32'h5a827999;
  k[49] = 32'h6ed9eba1;
  k[50] = 32'h8f1bbcdc;
  k[51] = 32'hca62c1d6;
  k[52] = 32'h5a827999;
  k[53] = 32'h6ed9eba1;
  k[54] = 32'h8f1bbcdc;
  k[55] = 32'hca62c1d6;
  k[56] = 32'h5a827999;
  k[57] = 32'h6ed9eba1;
  k[58] = 32'h8f1bbcdc;
  k[59] = 32'hca62c1d6;
  k[60] = 32'h5a827999;
  k[61] = 32'h6ed9eba1;
  k[62] = 32'h8f1bbcdc;
  k[63] = 32'hca62c1d6;
  k[64] = 32'h5a827999;
  k[65] = 32'h6ed9eba1;
  k[66] = 32'h8f1bbcdc;
  k[67] = 32'hca62c1d6;
  k[68] = 32'h5a827999;
  k[69] = 32'h6ed9eba1;
  k[70] = 32'h8f1bbcdc;
  k[71] = 32'hca62c1d6;
  k[72] = 32'h5a827999;
  k[73] = 32'h6ed9eba1;
  k[74] = 32'h8f1bbcdc;
  k[75] = 32'hca62c1d6;
  k[76] = 32'h5a827999;
  k[77] = 32'h6ed9eba1;
  k[78] = 32'h8f1bbcdc;
  k[79] = 32'hca62c1d6;
end

// 消息扩展
always @(*) begin
  for (i = 0; i < 16; i = i + 1) begin
    w[i] = message[i*32 +: 32];
  end

  for (i = 16; i < 80; i = i + 1) begin
    w[i] = w[i-3] ^ w[i-8] ^ w[i-14] ^ w[i-16];
    w[i] = {w[i][30:0], w[i][31]};
  end
end

// 哈希计算
always @(posedge clk) begin
  if (rst) begin
    a <= h0;
    b <= h1;
    c <= h2;
    d <= h3;
    e <= h4;
  end else begin
    for (i = 0; i < 80; i = i + 1) begin
      if (i <= 19) begin
        f <= (b & c) | ((~b) & d);
        k_i <= k[i];
      end else if (i <= 39) begin
        f <= b ^ c ^ d;
        k_i <= k[i];
      end else if (i <= 59) begin
        f <= (b & c) | (b & d) | (c & d);
        k_i <= k[i];
      end else begin
        f <= b ^ c ^ d;
        k_i <= k[i];
      end

      temp <= leftRotate(a, 5) + f + e + k_i + w[i];
      e <= d;
      d <= c;
      c <= leftRotate(b, 30);
      b <= a;
      a <= temp;
    end

    hash <= {a, b, c, d, e};
  end
end

// 左移
function [31:0] leftRotate;
  input [31:0] value;
  input [4:0] amount;
  begin
    leftRotate = {value[amount-1:0], value[31:amount]};
  end
endfunction

endmodule