-- "blowfishvhdl" is a free synthesizable VHDL Blowfish implementation
-- Copyright (C) 2000  Wesley J. Landaker <wjl@mindless.com>

-- 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 2 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, write to the Free Software
-- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-- See http://blowfishvhdl.sourceforge.net for more information.

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;

entity keychunker is
port (
  key       : in  std_logic_vector(447 downto 0);
  key_size  : in  std_logic_vector(3 downto 0);  -- key size in 32-bit chunks

  keychunk_blob  : out std_logic_vector(447 downto 0)

);
end keychunker;

architecture fishy of keychunker is

  type KEYCHUNK_TYPE is array (0 to 13) of std_logic_vector(31 downto 0); 
  signal keychunk : KEYCHUNK_TYPE;

begin

  keychunk_blob(31 downto 0) <= keychunk(0);
  keychunk_blob(63 downto 32) <= keychunk(1);
  keychunk_blob(95 downto 64) <= keychunk(2);
  keychunk_blob(127 downto 96) <= keychunk(3);
  keychunk_blob(159 downto 128) <= keychunk(4);
  keychunk_blob(191 downto 160) <= keychunk(5);
  keychunk_blob(223 downto 192) <= keychunk(6);
  keychunk_blob(255 downto 224) <= keychunk(7);
  keychunk_blob(287 downto 256) <= keychunk(8);
  keychunk_blob(319 downto 288) <= keychunk(9);
  keychunk_blob(351 downto 320) <= keychunk(10);
  keychunk_blob(383 downto 352) <= keychunk(11);
  keychunk_blob(415 downto 384) <= keychunk(12);
  keychunk_blob(447 downto 416) <= keychunk(13);

  -- a process to chunk up the key ;
  -- if the key_size was to be hard_coded, this could be eliminated
  -- and reduce the logic for this implementation quite a bit.
  process(key, key_size)
  begin
    case key_size is
      when "0001" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(31 downto 0);
        keychunk(2) <= key(31 downto 0);
        keychunk(3) <= key(31 downto 0);
        keychunk(4) <= key(31 downto 0);
        keychunk(5) <= key(31 downto 0);
        keychunk(6) <= key(31 downto 0);
        keychunk(7) <= key(31 downto 0);
        keychunk(8) <= key(31 downto 0);
        keychunk(9) <= key(31 downto 0);
        keychunk(10) <= key(31 downto 0);
        keychunk(11) <= key(31 downto 0);
        keychunk(12) <= key(31 downto 0);
        keychunk(13) <= key(31 downto 0);
      when "0010" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(31 downto 0);
        keychunk(3) <= key(63 downto 32);
        keychunk(4) <= key(31 downto 0);
        keychunk(5) <= key(63 downto 32);
        keychunk(6) <= key(31 downto 0);
        keychunk(7) <= key(63 downto 32);
        keychunk(8) <= key(31 downto 0);
        keychunk(9) <= key(63 downto 32);
        keychunk(10) <= key(31 downto 0);
        keychunk(11) <= key(63 downto 32);
        keychunk(12) <= key(31 downto 0);
        keychunk(13) <= key(63 downto 32);
      when "0011" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(31 downto 0);
        keychunk(4) <= key(63 downto 32);
        keychunk(5) <= key(95 downto 64);
        keychunk(6) <= key(31 downto 0);
        keychunk(7) <= key(63 downto 32);
        keychunk(8) <= key(95 downto 64);
        keychunk(9) <= key(31 downto 0);
        keychunk(10) <= key(63 downto 32);
        keychunk(11) <= key(95 downto 64);
        keychunk(12) <= key(31 downto 0);
        keychunk(13) <= key(63 downto 32);
      when "0100" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(31 downto 0);
        keychunk(5) <= key(63 downto 32);
        keychunk(6) <= key(95 downto 64);
        keychunk(7) <= key(127 downto 96);
        keychunk(8) <= key(31 downto 0);
        keychunk(9) <= key(63 downto 32);
        keychunk(10) <= key(95 downto 64);
        keychunk(11) <= key(127 downto 96);
        keychunk(12) <= key(31 downto 0);
        keychunk(13) <= key(63 downto 32);
      when "0101" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(31 downto 0);
        keychunk(6) <= key(63 downto 32);
        keychunk(7) <= key(95 downto 64);
        keychunk(8) <= key(127 downto 96);
        keychunk(9) <= key(159 downto 128);
        keychunk(10) <= key(31 downto 0);
        keychunk(11) <= key(63 downto 32);
        keychunk(12) <= key(95 downto 64);
        keychunk(13) <= key(127 downto 96);
      when "0110" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(191 downto 160);
        keychunk(6) <= key(31 downto 0);
        keychunk(7) <= key(63 downto 32);
        keychunk(8) <= key(95 downto 64);
        keychunk(9) <= key(127 downto 96);
        keychunk(10) <= key(159 downto 128);
        keychunk(11) <= key(191 downto 160);
        keychunk(12) <= key(31 downto 0);
        keychunk(13) <= key(63 downto 32);
      when "0111" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(191 downto 160);
        keychunk(6) <= key(223 downto 192);
        keychunk(7) <= key(31 downto 0);
        keychunk(8) <= key(63 downto 32);
        keychunk(9) <= key(95 downto 64);
        keychunk(10) <= key(127 downto 96);
        keychunk(11) <= key(159 downto 128);
        keychunk(12) <= key(191 downto 160);
        keychunk(13) <= key(223 downto 192);
      when "1000" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(191 downto 160);
        keychunk(6) <= key(223 downto 192);
        keychunk(7) <= key(255 downto 224);
        keychunk(8) <= key(31 downto 0);
        keychunk(9) <= key(63 downto 32);
        keychunk(10) <= key(95 downto 64);
        keychunk(11) <= key(127 downto 96);
        keychunk(12) <= key(159 downto 128);
        keychunk(13) <= key(191 downto 160);
      when "1001" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(191 downto 160);
        keychunk(6) <= key(223 downto 192);
        keychunk(7) <= key(255 downto 224);
        keychunk(8) <= key(287 downto 256);
        keychunk(9) <= key(31 downto 0);
        keychunk(10) <= key(63 downto 32);
        keychunk(11) <= key(95 downto 64);
        keychunk(12) <= key(127 downto 96);
        keychunk(13) <= key(159 downto 128);
      when "1010" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(191 downto 160);
        keychunk(6) <= key(223 downto 192);
        keychunk(7) <= key(255 downto 224);
        keychunk(8) <= key(287 downto 256);
        keychunk(9) <= key(319 downto 288);
        keychunk(10) <= key(31 downto 0);
        keychunk(11) <= key(63 downto 32);
        keychunk(12) <= key(95 downto 64);
        keychunk(13) <= key(127 downto 96);
      when "1011" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(191 downto 160);
        keychunk(6) <= key(223 downto 192);
        keychunk(7) <= key(255 downto 224);
        keychunk(8) <= key(287 downto 256);
        keychunk(9) <= key(319 downto 288);
        keychunk(10) <= key(351 downto 320);
        keychunk(11) <= key(31 downto 0);
        keychunk(12) <= key(63 downto 32);
        keychunk(13) <= key(95 downto 64);
      when "1100" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(191 downto 160);
        keychunk(6) <= key(223 downto 192);
        keychunk(7) <= key(255 downto 224);
        keychunk(8) <= key(287 downto 256);
        keychunk(9) <= key(319 downto 288);
        keychunk(10) <= key(351 downto 320);
        keychunk(11) <= key(383 downto 352);
        keychunk(12) <= key(31 downto 0);
        keychunk(13) <= key(63 downto 32);
      when "1101" =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(191 downto 160);
        keychunk(6) <= key(223 downto 192);
        keychunk(7) <= key(255 downto 224);
        keychunk(8) <= key(287 downto 256);
        keychunk(9) <= key(319 downto 288);
        keychunk(10) <= key(351 downto 320);
        keychunk(11) <= key(383 downto 352);
        keychunk(12) <= key(415 downto 384);
        keychunk(13) <= key(31 downto 0);
      when others =>
        keychunk(0) <= key(31 downto 0);
        keychunk(1) <= key(63 downto 32);
        keychunk(2) <= key(95 downto 64);
        keychunk(3) <= key(127 downto 96);
        keychunk(4) <= key(159 downto 128);
        keychunk(5) <= key(191 downto 160);
        keychunk(6) <= key(223 downto 192);
        keychunk(7) <= key(255 downto 224);
        keychunk(8) <= key(287 downto 256);
        keychunk(9) <= key(319 downto 288);
        keychunk(10) <= key(351 downto 320);
        keychunk(11) <= key(383 downto 352);
        keychunk(12) <= key(415 downto 384);
        keychunk(13) <= key(447 downto 416);
    end case;
  end process;


end;