aes_package.vhd

Consecutive AES core Description of project.. Features - AES encoder - 128/192/256 bit -

  when "11101101" => inv_data := X"53";
  when "11101110" => inv_data := X"99";
  when "11101111" => inv_data := X"61";
  when "11110000" => inv_data := X"17";
  when "11110001" => inv_data := X"2b";
  when "11110010" => inv_data := X"04";
  when "11110011" => inv_data := X"7e";
  when "11110100" => inv_data := X"ba";
  when "11110101" => inv_data := X"77";
  when "11110110" => inv_data := X"d6";
  when "11110111" => inv_data := X"26";
  when "11111000" => inv_data := X"e1";
  when "11111001" => inv_data := X"69";
  when "11111010" => inv_data := X"14";
  when "11111011" => inv_data := X"63";
  when "11111100" => inv_data := X"55";
  when "11111101" => inv_data := X"21";
  when "11111110" => inv_data := X"0c";
  when "11111111" => inv_data := X"7d";
  when others => null;  
end case;
inv_data_stdlogic := to_StdLogicVector(inv_data);
return inv_data_stdlogic;
end function inv_sbox_val;

function col_transform(p: state_array_type) return std_logic_vector is
 variable result: std_logic_vector(7 downto 0);
 variable m,n: std_logic_vector(7 downto 0);
 begin 
   if(p(0)(7) = '1') then
     m := (p(0)(6 downto 0) & '0') xor "00011011";
   else
     m := (p(0)(6 downto 0) & '0');
   end if;
   if(p(1)(7) = '1') then
     n := (p(1)(6 downto 0) & '0') xor "00011011" xor p(1);
   else
     n := (p(1)(6 downto 0) & '0') xor p(1);
   end if;
   result := m xor n xor p(2) xor p(3);
   return result;
end function col_transform;

function col_inv_transform(s: state_array_type) return std_logic_vector is
variable result: std_logic_vector(7 downto 0);
variable sub0,sub1,sub2,sub3: std_logic_vector(7 downto 0);
variable x0,y0,z0: std_logic_vector(7 downto 0);
variable x1,y1,z1: std_logic_vector(7 downto 0);
variable x2,y2,z2: std_logic_vector(7 downto 0);
variable x3,y3,z3: std_logic_vector(7 downto 0);
begin
  if(s(0)(7) = '1') then
    x0 := (s(0)(6 downto 0) & '0') xor "00011011";
  else
    x0 := (s(0)(6 downto 0) & '0');
  end if;
  if(x0(7) = '1') then
    y0 := (x0(6 downto 0) & '0') xor "00011011";
  else
    y0 := (x0(6 downto 0) & '0');
  end if;
  if(y0(7) = '1') then
    z0 := (y0(6 downto 0) & '0') xor "00011011";
  else
    z0 := (y0(6 downto 0) & '0');
  end if;
  sub0 := (x0 xor y0 xor z0);----------

  if(s(1)(7) = '1') then
    x1 := (s(1)(6 downto 0) & '0') xor "00011011";
  else
    x1 := (s(1)(6 downto 0) & '0');
  end if;
  if(x1(7) = '1') then
    y1 := (x1(6 downto 0) & '0') xor "00011011";
  else
    y1 := (x1(6 downto 0) & '0');
  end if;
  if(y1(7) = '1') then
    z1 := (y1(6 downto 0) & '0') xor "00011011";
  else
    z1 := (y1(6 downto 0) & '0');
  end if;
  sub1 := (x1 xor z1 xor s(1));----------

  if(s(2)(7) = '1') then
    x2 := (s(2)(6 downto 0) & '0') xor "00011011";
  else
    x2 := (s(2)(6 downto 0) & '0');
  end if;
  if(x2(7) = '1') then
    y2 := (x2(6 downto 0) & '0') xor "00011011";
  else
    y2 := (x2(6 downto 0) & '0');
  end if;
  if(y2(7) = '1') then
    z2 := (y2(6 downto 0) & '0') xor "00011011";
  else
    z2 := (y2(6 downto 0) & '0');
  end if;
  sub2 := (y2 xor z2 xor s(2));----------

  if(s(3)(7) = '1') then
    x3 := (s(3)(6 downto 0) & '0') xor "00011011";
  else
    x3 := (s(3)(6 downto 0) & '0');
  end if;
  if(x3(7) = '1') then
    y3 := (x3(6 downto 0) & '0') xor "00011011";
  else
    y3 := (x3(6 downto 0) & '0');
  end if;
  if(y3(7) = '1') then
    z3 := (y3(6 downto 0) & '0') xor "00011011";
  else
    z3 := (y3(6 downto 0) & '0');
  end if;
  sub3 := (z3 xor s(3));----------
  
  result := sub0 xor sub1 xor sub2 xor sub3;
  return result;
end function col_inv_transform;

-- combo logic for mix columns
function mix_cols_routine
     (
       a_r0 :state_array_type;
       a_r1 :state_array_type;
       a_r2 :state_array_type;
       a_r3 :state_array_type;
       mode :std_logic
     )
return std_logic_vector is
variable b      : std_logic_vector(0 to 127);
variable b0     : state_array_type;
variable b1     : state_array_type;
variable b2     : state_array_type;
variable b3     : state_array_type;
-------------------------------------------------
variable b_0_0  : std_logic_vector(7 downto 0);
variable s_0_0  : state_array_type;
--------------------------------------------------
variable b_0_1  : std_logic_vector(7 downto 0);
variable s_0_1  : state_array_type;
--------------------------------------------------
variable b_0_2  : std_logic_vector(7 downto 0);
variable s_0_2  : state_array_type;
----------------------------------------------
variable b_0_3  : std_logic_vector(7 downto 0);
variable s_0_3  : state_array_type;
----------------------------------------------
variable b_1_0  : std_logic_vector(7 downto 0);
variable s_1_0  : state_array_type;
----------------------------------------------
variable b_1_1  : std_logic_vector(7 downto 0);
variable s_1_1  : state_array_type;
----------------------------------------------
variable b_1_2  : std_logic_vector(7 downto 0);
variable s_1_2  : state_array_type;
----------------------------------------------
variable b_1_3  : std_logic_vector(7 downto 0);
variable s_1_3  : state_array_type;
----------------------------------------------
variable b_2_0  : std_logic_vector(7 downto 0);
variable s_2_0  : state_array_type;
----------------------------------------------
variable b_2_1  : std_logic_vector(7 downto 0);
variable s_2_1  : state_array_type;
----------------------------------------------
variable b_2_2  : std_logic_vector(7 downto 0);
variable s_2_2  : state_array_type;
----------------------------------------------
variable b_2_3  : std_logic_vector(7 downto 0);
variable s_2_3  : state_array_type;
----------------------------------------------
variable b_3_0  : std_logic_vector(7 downto 0);
variable s_3_0  : state_array_type;
----------------------------------------------
variable b_3_1  : std_logic_vector(7 downto 0);
variable s_3_1  : state_array_type;
----------------------------------------------
variable b_3_2  : std_logic_vector(7 downto 0);
variable s_3_2  : state_array_type;
----------------------------------------------
variable b_3_3  : std_logic_vector(7 downto 0);
variable s_3_3  : state_array_type;
--------------------------------------------------
begin
if(mode = '1') then
  s_0_0 := a_r0;
  b_0_0 := col_transform(s_0_0);
------------------------------------------------------
  s_0_1 := a_r1;
  b_0_1 := col_transform(s_0_1);
------------------------------------------------------
  s_0_2 := a_r2;
  b_0_2 := col_transform(s_0_2);
------------------------------------------------------
  s_0_3 := a_r3;
  b_0_3 := col_transform(s_0_3);
--****************************************************************
  s_1_0 := (a_r0(1),a_r0(2),a_r0(3),a_r0(0));
  b_1_0 := col_transform(s_1_0);
------------------------------------------------------
  s_1_1 := (a_r1(1),a_r1(2),a_r1(3),a_r1(0));
  b_1_1 := col_transform(s_1_1);
------------------------------------------------------
  s_1_2 := (a_r2(1),a_r2(2),a_r2(3),a_r2(0));
  b_1_2 := col_transform(s_1_2);
------------------------------------------------------
  s_1_3 := (a_r3(1),a_r3(2),a_r3(3),a_r3(0));
  b_1_3 := col_transform(s_1_3);
--****************************************************************
  s_2_0 := (a_r0(2),a_r0(3),a_r0(0),a_r0(1));
  b_2_0 := col_transform(s_2_0);
------------------------------------------------------
  s_2_1 := (a_r1(2),a_r1(3),a_r1(0),a_r1(1));
  b_2_1 := col_transform(s_2_1);
------------------------------------------------------
  s_2_2 := (a_r2(2),a_r2(3),a_r2(0),a_r2(1));
  b_2_2 := col_transform(s_2_2);
------------------------------------------------------
  s_2_3 := (a_r3(2),a_r3(3),a_r3(0),a_r3(1));
  b_2_3 := col_transform(s_2_3);
--****************************************************************
  s_3_0 := (a_r0(3),a_r0(0),a_r0(1),a_r0(2));
  b_3_0 := col_transform(s_3_0);
------------------------------------------------------
  s_3_1 := (a_r1(3),a_r1(0),a_r1(1),a_r1(2));
  b_3_1 := col_transform(s_3_1);
------------------------------------------------------
  s_3_2 := (a_r2(3),a_r2(0),a_r2(1),a_r2(2));
  b_3_2 := col_transform(s_3_2);
------------------------------------------------------
  s_3_3 := (a_r3(3),a_r3(0),a_r3(1),a_r3(2));
  b_3_3 := col_transform(s_3_3);
--****************************************************************
else       
  s_0_0 := a_r0;
  b_0_0 := col_inv_transform(s_0_0);
------------------------------------------------------
  s_0_1 := a_r1;
  b_0_1 := col_inv_transform(s_0_1);
------------------------------------------------------
  s_0_2 := a_r2;
  b_0_2 := col_inv_transform(s_0_2);
------------------------------------------------------
  s_0_3 := a_r3;
  b_0_3 := col_inv_transform(s_0_3);
--****************************************************************
  s_1_0 := (a_r0(1),a_r0(2),a_r0(3),a_r0(0));
  b_1_0 := col_inv_transform(s_1_0);
------------------------------------------------------
  s_1_1 := (a_r1(1),a_r1(2),a_r1(3),a_r1(0));
  b_1_1 := col_inv_transform(s_1_1);
------------------------------------------------------
  s_1_2 := (a_r2(1),a_r2(2),a_r2(3),a_r2(0));
  b_1_2 := col_inv_transform(s_1_2);
------------------------------------------------------
  s_1_3 := (a_r3(1),a_r3(2),a_r3(3),a_r3(0));
  b_1_3 := col_inv_transform(s_1_3);
--****************************************************************
  s_2_0 := (a_r0(2),a_r0(3),a_r0(0),a_r0(1));
  b_2_0 := col_inv_transform(s_2_0);
------------------------------------------------------
  s_2_1 := (a_r1(2),a_r1(3),a_r1(0),a_r1(1));
  b_2_1 := col_inv_transform(s_2_1);
------------------------------------------------------
  s_2_2 := (a_r2(2),a_r2(3),a_r2(0),a_r2(1));
  b_2_2 := col_inv_transform(s_2_2);
------------------------------------------------------
  s_2_3 := (a_r3(2),a_r3(3),a_r3(0),a_r3(1));
  b_2_3 := col_inv_transform(s_2_3);
--****************************************************************
  s_3_0 := (a_r0(3),a_r0(0),a_r0(1),a_r0(2));
  b_3_0 := col_inv_transform(s_3_0);
------------------------------------------------------
  s_3_1 := (a_r1(3),a_r1(0),a_r1(1),a_r1(2));
  b_3_1 := col_inv_transform(s_3_1);
------------------------------------------------------
  s_3_2 := (a_r2(3),a_r2(0),a_r2(1),a_r2(2));
  b_3_2 := col_inv_transform(s_3_2);
------------------------------------------------------
  s_3_3 := (a_r3(3),a_r3(0),a_r3(1),a_r3(2));
  b_3_3 := col_inv_transform(s_3_3);
--****************************************************************
end if;
b := (b_0_0 & b_1_0 & b_2_0 & b_3_0 & b_0_1 & b_1_1 & b_2_1 & b_3_1 &
      b_0_2 & b_1_2 & b_2_2 & b_3_2 & b_0_3 & b_1_3 & b_2_3 & b_3_3);
return b;
end function mix_cols_routine;

end package body aes_package;