mixcolumns.balsa

(--
    This file is part of naive-AES-balsa.

    naive-AES-balsa 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.

    naive-AES-balsa 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 naive-AES-balsa.  If not, see <http://www.gnu.org/licenses/>.
--)

import [balsa.types.basic]

import [mixcolumn]

--Version for key arranged as:
-- 0 4 8 C
-- 1 5 9 D
-- 2 6 A E
-- 3 7 B F

procedure mixcolumns (input i : 128 bits;
	              output o : 128 bits) is
   array 4 of channel col, mix : 32 bits
begin
   for || k in 0..3 then
      mixcolumn(col[k], mix[k])
   end ||
   loop i -> then
      col[0] <- (#i[0..31] as 32 bits) ||
      col[1] <- (#i[32..63] as 32 bits) ||
      col[2] <- (#i[64..95] as 32 bits) ||
      col[3] <- (#i[96..127] as 32 bits) ||
      select mix[0], mix[1], mix[2], mix[3] then
         o <- ((#(mix[0]) @ #(mix[1]) @ #(mix[2]) @ #(mix[3])) as 128 bits)
      end
   end end
end


-- Version for key arranged as:
-- 0 1 2 3
-- 4 5 6 7
-- 8 9 A B
-- C D E F
(--
procedure mixcolumns (input i : array 16 of byte;
	              output o : array 16 of byte) is
   array 4 of channel col, mix : array 4 of byte
begin
   loop i -> then
      -- TODO: Make strided loop
      col[0] <- {i[0], i[4], i[8], i[12]} ||
      col[1] <- {i[0+1], i[4+1], i[8+1], i[12+1]} ||
      col[2] <- {i[0+2], i[4+2], i[8+2], i[12+2]} ||
      col[3] <- {i[0+3], i[4+3], i[8+3], i[12+3]}
   end end ||
   for || k in 0..3 then
      mixcolumn(col[k], mix[k])
   end ||
   loop
   mix[0], mix[1], mix[2], mix[3] -> then
      o <- {mix[0][0], mix[1][0], mix[2][0], mix[3][0],
            mix[0][1], mix[1][1], mix[2][1], mix[3][1],
            mix[0][2], mix[1][2], mix[2][2], mix[3][2],
            mix[0][3], mix[1][3], mix[2][3], mix[3][3]
           }
   end end
end
--)