Subversion Repositories sha256core

-- Copyright (c) 2013 Antonio de la Piedra

-- This program is free software: you can redistribute it and/or modify

-- it under the terms of the GNU General Public License as published by

-- the Free Software Foundation, either version 3 of the License, or

-- (at your option) any later version.

-- This program is distributed in the hope that it will be useful,

-- but WITHOUT ANY WARRANTY; without even the implied warranty of

-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-- GNU General Public License for more details.

-- You should have received a copy of the GNU General Public License

-- along with this program.  If not, see <http://www.gnu.org/licenses/>.

library IEEE;

use IEEE.STD_LOGIC_1164.all;

package sha_fun is

  function sigma_0  (signal x : in std_logic_vector) return std_logic_vector;

  function sigma_1  (signal x : in std_logic_vector) return std_logic_vector;

  function sum_0  (signal x : in std_logic_vector) return std_logic_vector;

  function sum_1  (signal x : in std_logic_vector) return std_logic_vector;

  function chi  (signal x : in std_logic_vector;

                                          signal y : in std_logic_vector;

                                          signal z : in std_logic_vector) return std_logic_vector;

  function maj  (signal x : in std_logic_vector;

                                          signal y : in std_logic_vector;

                                          signal z : in std_logic_vector) return std_logic_vector;

end sha_fun;

package body sha_fun is

  function sigma_0  (signal x : in std_logic_vector) return std_logic_vector is

        variable tmp_0 : std_logic_vector(31 downto 0);

        variable tmp_1 : std_logic_vector(31 downto 0);

        variable tmp_2 : std_logic_vector(31 downto 0);

        variable r : std_logic_vector(31 downto 0);

  begin

        tmp_0 := x(6 downto 0) & x(31 downto 7);

        tmp_1 := x(17 downto 0) & x(31 downto 18);

        tmp_2 := "000" & x(31 downto 3);

        r := tmp_0 xor tmp_1 xor tmp_2;

        return r;

  end sigma_0;

  function sigma_1  (signal x : in std_logic_vector) return std_logic_vector is

        variable tmp_0 : std_logic_vector(31 downto 0);

        variable tmp_1 : std_logic_vector(31 downto 0);

        variable tmp_2 : std_logic_vector(31 downto 0);

        variable r : std_logic_vector(31 downto 0);

  begin

        tmp_0 := x(16 downto 0) & x(31 downto 17);

        tmp_1 := x(18 downto 0) & x(31 downto 19);

        tmp_2 := "0000000000" & x(31 downto 10);

        r := tmp_0 xor tmp_1 xor tmp_2;

        return r;

  end sigma_1;

  function chi  (signal x : in std_logic_vector;

                                          signal y : in std_logic_vector;

                                          signal z : in std_logic_vector) return std_logic_vector is

    variable r : std_logic_vector(31 downto 0);

  begin

                        r := (x and y) xor (not(x) and z);

                        return r;

  end chi;

  function maj  (signal x : in std_logic_vector;

                                          signal y : in std_logic_vector;

                                          signal z : in std_logic_vector) return std_logic_vector is

          variable r : std_logic_vector(31 downto 0);

  begin

                   r := (x and y) xor (x and z) xor (y and z);

                        return r;

  end maj;

  function sum_0  (signal x : in std_logic_vector) return std_logic_vector is

        variable tmp_0 : std_logic_vector(31 downto 0);

        variable tmp_1 : std_logic_vector(31 downto 0);

        variable tmp_2 : std_logic_vector(31 downto 0);

        variable r : std_logic_vector(31 downto 0);

  begin

        tmp_0 := x(1 downto 0) & x(31 downto 2);

        tmp_1 := x(12 downto 0) & x(31 downto 13);

        tmp_2 := x(21 downto 0) & x(31 downto 22);

        r := tmp_0 xor tmp_1 xor tmp_2;

        return r;

  end sum_0;

  function sum_1  (signal x : in std_logic_vector) return std_logic_vector is

        variable tmp_0 : std_logic_vector(31 downto 0);

        variable tmp_1 : std_logic_vector(31 downto 0);

        variable tmp_2 : std_logic_vector(31 downto 0);

        variable r : std_logic_vector(31 downto 0);

  begin

        tmp_0 := x(5 downto 0) & x(31 downto 6);

        tmp_1 := x(10 downto 0) & x(31 downto 11);

        tmp_2 := x(24 downto 0) & x(31 downto 25);

        r := tmp_0 xor tmp_1 xor tmp_2;

        return r;

  end sum_1;

 end sha_fun;