key_expansion.vhdl

AES Core Modules In this document I describe components designated to encoding and decoding using A

               i_INTERN_ADDR_RD0 <= i_INTERN_ADDR_RD0 + 1;
            elsif v_CALCULATION_CNTR = x"0A" then
               i_INTERN_ADDR_RD0 <= i_INTERN_ADDR_RD0 + 1;
            elsif KEY_SIZE = 1 then
               if v_CALCULATION_CNTR = x"0B" then
                  i_INTERN_ADDR_RD0 <= i_INTERN_ADDR_RD0 + 1;
               elsif v_CALCULATION_CNTR = x"0C" then
                  i_INTERN_ADDR_RD0 <= i_INTERN_ADDR_RD0 + 1;
               end if;
            elsif KEY_SIZE = 2 then
               if v_CALCULATION_CNTR = x"10" then
                  i_INTERN_ADDR_RD0 <= i_INTERN_ADDR_RD0 + 1;
               elsif v_CALCULATION_CNTR = x"11" then
                  i_INTERN_ADDR_RD0 <= i_INTERN_ADDR_RD0 + 1;
               elsif v_CALCULATION_CNTR = x"12" then
                  i_INTERN_ADDR_RD0 <= i_INTERN_ADDR_RD0 + 1;
               elsif v_CALCULATION_CNTR = x"13" then
                  i_INTERN_ADDR_RD0 <= i_INTERN_ADDR_RD0 + 1;
               end if;
            end if;
         end if;

         FF_GET_KEY <= GET_KEY_I;
      end if;
   end process;

i_EXTERN_ADDRESS <= conv_integer(KEY_NUMB_I);

i_SRAM_ADDR_RD0   <= i_INTERN_ADDR_RD0 when GET_KEY_I = '0' else i_EXTERN_ADDRESS;

KEY_EXP_O         <= v_KEY_COL_OUT0 when  FF_GET_KEY  = '1' else (others => '0');

--****************************************************************************--
--* ROM for Sub Word                                                         *--
--****************************************************************************--
i_FRW_ADD_RD0 <= conv_integer(v_TEMP_VECTOR(7 downto 0)) when v_CALCULATION_CNTR = x"02"   else
                 conv_integer(v_TEMP_VECTOR(15 downto 8)) when v_CALCULATION_CNTR = x"03"  else
                 conv_integer(v_TEMP_VECTOR(23 downto 16)) when v_CALCULATION_CNTR = x"04" else
                 conv_integer(v_TEMP_VECTOR(31 downto 24)) when v_CALCULATION_CNTR = x"05" else
                 conv_integer(v_TEMP_VECTOR(7 downto 0)) when v_CALCULATION_CNTR = x"0C" and KEY_SIZE = 2  else
                 conv_integer(v_TEMP_VECTOR(15 downto 8)) when v_CALCULATION_CNTR = x"0D" and KEY_SIZE = 2  else
                 conv_integer(v_TEMP_VECTOR(23 downto 16)) when v_CALCULATION_CNTR = x"0E" and KEY_SIZE = 2 else
                 conv_integer(v_TEMP_VECTOR(31 downto 24)) when v_CALCULATION_CNTR = x"0F" and KEY_SIZE = 2 else
                 0;



ROM0:
   process(CLK_I)
   begin
      if rising_edge(CLK_I) then
         if CE_I = '1' then
            v_SUB_WORD  <= t_FORWARD_TABLE(i_FRW_ADD_RD0);
         end if;
      end if;
   end process;


--****************************************************************************--
--* v_KEY_COL_IN0                                                            *--
--****************************************************************************--


v_KEY_COL_IN0 <=  v_KEY32_IN     when FF_VALID_KEY = '1' and i_BYTE_CNTR4 = 0 else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"09" else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"0A" else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"0B" else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"0C" else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"0D" and KEY_SIZE = 1 else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"0E" and KEY_SIZE = 1 else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"12" and KEY_SIZE = 2 else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"13" and KEY_SIZE = 2 else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"14" and KEY_SIZE = 2 else
                  v_TEMP_VECTOR  when v_CALCULATION_CNTR = x"15" and KEY_SIZE = 2 else
                  (others => '0');

--****************************************************************************--
--* CALCULATION                                                              *--
--****************************************************************************--

P0002:
	process(CLK_I)
	begin
		if rising_edge(CLK_I) then
         if RESET_I = '1' then
            START_CALCULATION <= '0';
            CALCULATION <= '0';
            DONE_O <= '0';
         elsif CE_I = '1' then
            if FF_VALID_KEY = '1' and VALID_KEY_I = '0' then
               START_CALCULATION <= '1';
               CALCULATION <= '1';
               DONE_O <= '0';
            elsif i_ROUND = 10 and KEY_SIZE = 0 then
               DONE_O <= '1';
               CALCULATION <= '0';
            elsif i_ROUND = 8 and KEY_SIZE = 1 then
               DONE_O <= '1';
               CALCULATION <= '0';
            elsif i_ROUND = 7 and KEY_SIZE = 2 then
               DONE_O <= '1';
               CALCULATION <= '0';
            else
               START_CALCULATION <= '0';
            end if;
         end if;
		end if;
	end process;

P0003:
	process(CLK_I)
	begin
		if rising_edge(CLK_I) then
         if RESET_I = '1' then
            v_CALCULATION_CNTR <= (others => '0');
            i_ROUND <= 0;
         elsif CE_I = '1' then
            if START_CALCULATION = '1' then
               v_CALCULATION_CNTR <= (others => '0');
               i_ROUND <= 0;
            elsif v_CALCULATION_CNTR = x"0C" and KEY_SIZE = 0 then
               v_CALCULATION_CNTR <= (others => '0');
               i_ROUND <= i_ROUND + 1;
            elsif v_CALCULATION_CNTR = x"0E" and KEY_SIZE = 1 then
               v_CALCULATION_CNTR <= (others => '0');
               i_ROUND <= i_ROUND + 1;
            elsif v_CALCULATION_CNTR = x"15" and KEY_SIZE = 2 then
               v_CALCULATION_CNTR <= (others => '0');
               i_ROUND <= i_ROUND + 1;
            elsif CALCULATION = '1' then
               v_CALCULATION_CNTR <= v_CALCULATION_CNTR + 1;
            else
               v_CALCULATION_CNTR <= (others => '0');
            end if;
         end if;
		end if;
	end process;
--****************************************************************************--
--* v_TEMP_VECTOR                                                            *--
--****************************************************************************--
P0:
	process(CLK_I)
	begin
		if rising_edge(CLK_I) then
			if RESET_I = '1' then
            v_TEMP_VECTOR <= (others => '0');
         elsif CE_I = '1' then
            if START_CALCULATION = '1' then
               v_TEMP_VECTOR <= v_KEY32_IN;
            elsif v_CALCULATION_CNTR = x"03" then
               v_TEMP_VECTOR(7 downto 0)     <= v_SUB_WORD;
            elsif v_CALCULATION_CNTR = x"04" then
               v_TEMP_VECTOR(15 downto 8)    <= v_SUB_WORD;
            elsif v_CALCULATION_CNTR = x"05" then
               v_TEMP_VECTOR(23 downto 16)   <= v_SUB_WORD;
            elsif v_CALCULATION_CNTR = x"06" then
               v_TEMP_VECTOR(31 downto 24)   <= v_SUB_WORD;

            elsif v_CALCULATION_CNTR = x"07" then
               v_TEMP_VECTOR   <= (v_TEMP_VECTOR(7 downto 0) & v_TEMP_VECTOR(31 downto 8)) xor (x"000000" & c_RCON(i_ROUND));
            elsif v_CALCULATION_CNTR = x"08" then
               v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
            elsif v_CALCULATION_CNTR = x"09" then
               v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
            elsif v_CALCULATION_CNTR = x"0A" then
               v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
            elsif v_CALCULATION_CNTR = x"0B" then
               v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
            elsif KEY_SIZE = 1 then
               if v_CALCULATION_CNTR = x"0C" then
                  v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
               elsif v_CALCULATION_CNTR = x"0D" then
                  v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
               end if;
            elsif KEY_SIZE = 2 then

               if v_CALCULATION_CNTR = x"0D" then
                  v_TEMP_VECTOR(7 downto 0)     <= v_SUB_WORD;
               elsif v_CALCULATION_CNTR = x"0E" then
                  v_TEMP_VECTOR(15 downto 8)    <= v_SUB_WORD;
               elsif v_CALCULATION_CNTR = x"0F" then
                  v_TEMP_VECTOR(23 downto 16)   <= v_SUB_WORD;
               elsif v_CALCULATION_CNTR = x"10" then
                  v_TEMP_VECTOR(31 downto 24)   <= v_SUB_WORD;

               elsif v_CALCULATION_CNTR = x"11" then
                  v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
               elsif v_CALCULATION_CNTR = x"12" then
                  v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
               elsif v_CALCULATION_CNTR = x"13" then
                  v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
               elsif v_CALCULATION_CNTR = x"14" then
                  v_TEMP_VECTOR   <= v_TEMP_VECTOR xor v_KEY_COL_OUT0;
               end if;

            end if;
         end if;
		end if;
	end process;

end Behavioral;