-- S.MG, 2018
 -- Testing of Serpent implementation using Nessie-format test vectors

with SMG_Serpent; use SMG_Serpent;

with Ada.Text_IO; use Ada.Text_IO;
with Ada.Command_Line; use Ada.Command_Line; -- set exit status on fail
with Interfaces; use Interfaces; -- unsigned_8

package body Test_Serpent is
  Test_Fail : exception;  -- raised if a test fails

  procedure test_from_file (filename: String) is 
    file     : FILE_TYPE;
    keylen   : constant := 256;
    blocklen : constant := 128;
    octets   : constant := 16;
    K        : Key;
    P, P2    : Block;	--plain text
    C, C2    : Block;	--cipher (encrypted) text
    times100 : Block;	--value after 100 iterations
    times1k  : Block;	--value after 1000 iterations
    W        : Key_Schedule;
    Test_No  : Positive := 1;
  begin
    begin
      open(file, In_File, filename);
      exception
      when others =>
        Put_Line(Standard_Error, "Can not open the file '" & filename & 
                                 "'. Does it exist?");
        Set_Exit_Status(Failure);
        return;
    end;

    loop
      declare
        Line1      : String := Get_Line(file);
        Line2      : String := Line1;
        key1, key2 : String( 1..octets*2 );
        len        : Natural := 0;
      begin
        --check if this is test data of any known kind
        if index( Line1, "key=", 1 ) > 0 then
          Line2 := Get_Line( file );
          key1  := Tail( Line1, octets*2  );
          key2  := Tail( Line2, octets*2 );
          for jj in 1..octets loop
            K(jj-1) := Unsigned_8'Value("16#" & 
                                        key1( ( jj - 1 ) * 2 + 1 .. jj * 2 ) & 
                                        "#");
            K( jj + octets - 1 ) :=
                       Unsigned_8'Value("16#" &
                                        key2( ( jj - 1 ) * 2 + 1 .. jj * 2 ) & 
                                        "#");
          end loop;

        elsif index( Line1, "plain=", 1 ) > 0 then
          key1 := Tail( Line1, octets * 2 );
          for jj in 1..octets loop
            P(jj-1) := Unsigned_8'Value("16#" & 
                                        key1( ( jj - 1 ) * 2 + 1 .. jj * 2 ) & 
                                        "#");
          end loop;
        elsif index( Line1, "cipher=", 1 ) > 0 then
          key1 := Tail( Line1, octets * 2 );
          for jj in 1..octets loop
            C(jj-1) := Unsigned_8'Value("16#" & 
                                        key1( ( jj - 1 ) * 2 + 1 .. jj * 2) & 
                                        "#");
          end loop;
        elsif index( Line1, "100 times=", 1 ) > 0 then
          key1 := Tail( Line1, octets * 2 );
          for jj in 1..octets loop
            times100(jj-1) := 
                       Unsigned_8'Value("16#" & 
                                        key1( ( jj - 1 ) * 2 + 1 .. jj * 2 ) & 
                                        "#");
          end loop;
        elsif index( Line1, "1000 times=", 1 ) > 0 then
          key1 := Tail( Line1, octets * 2 );
          for jj in 1..octets loop
            times1k(jj-1) := 
                       Unsigned_8'value("16#" & 
                                        key1( ( jj - 1 ) * 2 + 1 .. jj * 2 ) & 
                                        "#");
          end loop;
          --at this stage we should have ALL needed, so run test
          Put("-----Test " & Positive'Image(Test_No) & ": encryption...");
          Prepare_Key(K, W);
          Encrypt(W, P, C2);
          if C2 /= C then
            raise Test_Fail;
          else
            Put_Line("Passed-----");
          end if;
          Put("-----Test " & Positive'Image(Test_No) & ": decryption...");
          Decrypt(W, C2, P2);
          if P /= P2 then
            raise Test_Fail;
          else
            Put_Line("Passed-----");
          end if;

          Put("-----Test " & Positive'Image(Test_No) & ": 100 iterations...");
          for jj in 1 .. 100 loop
            Encrypt(W, P, C2);
            Decrypt(W, C2, P2);
            if (P2 /= P) then
              raise Test_Fail;
            end if;
            P := C2;
          end loop;
          Put_Line("Passed-----");

          Put("-----Test " & Positive'Image(Test_No) & ": 1000 iterations...");

          for jj in 1 .. 900 loop
            Encrypt(W, P, C2);
            Decrypt(W, C2, P2);
            if (P2 /= P) then
              raise Test_Fail;
            end if;
            P := C2;
          end loop;
          Put_Line("Passed-----");
          Test_No := Test_No + 1;					
        end if;	
        exit when End_Of_File(file);
      end;
    end loop;
    Close(file);
  end test_from_file;

  procedure test_one is
    K: Key;
    P, P2: Block;
    C: Block;
    W: Key_Schedule;
  begin
    K := (16#80#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#,
          16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#,
          16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#,
          16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#);

    P := (16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#,
          16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#, 16#00#);

    SMG_Serpent.Prepare_Key(K, W);
    Encrypt(W, P, C);
    if C /= (16#A2#, 16#23#, 16#AA#, 16#12#, 16#88#, 16#46#, 16#3C#, 16#0E#, 
             16#2B#, 16#E3#, 16#8E#, 16#BD#, 16#82#, 16#56#, 16#16#, 16#C0#)
      then
      raise Test_Fail;
    end if;

    for I in 1 .. 100 loop
      Encrypt(W, P, C);
      Decrypt(W, C, P2);
      if (P2 /= P) then
        raise Test_Fail;
      end if;
      P := C;
    end loop;

    if C /= (16#73#, 16#9E#, 16#01#, 16#48#, 16#97#, 16#1F#, 16#D9#, 16#75#, 
             16#B5#, 16#85#, 16#EA#, 16#FD#, 16#BD#, 16#65#, 16#9E#, 16#2C#)
      then
      raise Test_Fail;
    end if;

    for I in 1 .. 900 loop
      Encrypt(W, P, C);
      Decrypt(W, C, P2);
      if (P2 /= P) then
        raise Test_Fail;
      end if;
      P := C;
    end loop;

    if C /= (16#BE#, 16#FD#, 16#00#, 16#E0#, 16#D6#, 16#E2#, 16#7E#, 16#56#, 
             16#95#, 16#1D#, 16#C6#, 16#61#, 16#44#, 16#40#, 16#D2#, 16#86#)
      then
      raise Test_Fail;
    else
      Put_Line("PASSED: test single case.");
    end if;

  end test_one;

end Test_Serpent;