Hilfe bei Umstellung Unit DEC5.1 zu DEC6.0

[Kas Ob.]

Please try this:

Code:

unit Tools.Crypt;

interface

uses
  System.SysUtils, DECUtil, DECHash, DECCipherBase, DECCiphers, DECHashBase,
  DECFormatBase, DECFormat, DECRandom, DECHashAuthentication;

const
  conKey = 'aYr14iaz8u)xO7Ok';

var
  //CipherAlgo: TCipher_Rijndael;
  CipherMode: TCipherMode = cmCBCx;
  HashClass : TDECHashClass = THash_SHA256;
  TextFormat: TDECFormatClass = TFormat_Base64;
  KDFIndex  : Integer = 1;  // Iterations

type
  TToolsCrypt = class
  public
    class function Decrypt(aHash: string; aKey: string = ''): string;
    class function Encrypt(aText: string; aKey: string = ''): string;
  end;

implementation

{ TToolsCrypt }

class function TToolsCrypt.Decrypt(aHash, aKey: string): string;
var
  Cipher: TCipher_Rijndael;
  //Cipher: TDECCipher;
  Salt, Data, Check, Pass, Mac: TBytes;
  MacLength, SaltLen, DataLen: Integer;
begin
  if aKey = '' then
  begin
    aKey := conKey;
  end;

  //Cipher:=ValidCipher(TCipher_Rijndael).Create;       // the way it should be used ! but it fail now with DecodeBytes
  Cipher := TCipher_Rijndael.Create;
  try
    MacLength := Cipher.Context.BlockSize;
    SaltLen := Cipher.InitVectorSize;

    Salt := ValidFormat(TextFormat).Decode(BytesOf(aHash));
    DataLen := Length(Salt) - MacLength - Cipher.Context.BufferSize;

    Data := Copy(Salt, MacLength, DataLen);
    Check := Copy(Salt, DataLen + SaltLen, Cipher.Context.BufferSize);

    SetLength(Salt, SaltLen);
    Pass := ValidAuthenticationHash(HashClass).KDFx(aKey[Low(aKey)], Length(aKey) * SizeOf(Char), Salt[Low(Salt)], Length(Salt), Cipher.Context.KeySize, KDFIndex);

    Cipher.Mode := CipherMode;
    Cipher.Init(Pass, nil);
    SetLength(Result, DataLen div SizeOf(Char));

    Cipher.Decode(Data[Low(Data)], Result[Low(Result)], DataLen);
    //Result := StringOf(Cipher.DecodeBytes(Data,TFormat_Copy));
    Mac := BytesOf(Cipher.CalcMAC);
    if MacLength < Length(Check) then
      MacLength := Length(Check);

    if (MacLength <> Cipher.Context.BlockSize) or (not CompareMem(Check, Mac, MacLength)) then
    begin
      Result := '';
    end;

  finally
    Cipher.Free;
    ProtectBytes(Salt);
    ProtectBytes(Check);
    ProtectBytes(Data);
    ProtectBytes(Pass);
    ProtectBytes(Mac);
  end;
end;

class function TToolsCrypt.Encrypt(aText, aKey: string): string;
var
  Cipher: TCipher_Rijndael;
  Salt, Pass, Data, Mac: TBytes;
begin
  if aKey = '' then
  begin
    aKey := conKey;
  end;

  Cipher := TCipher_Rijndael.Create;
  try
    Salt := RandomBytes(Cipher.InitVectorSize);
    Pass := ValidAuthenticationHash(HashClass).KDFx(aKey[Low(aKey)], Length(aKey) * SizeOf(Char), Salt[Low(Salt)], Length(Salt), Cipher.Context.KeySize, KDFIndex);
    Cipher.Mode := CipherMode;

    Cipher.Mode := cmCBCx;
    Cipher.Init(Pass, nil);

    SetLength(Data, Length(aText) * SizeOf(Char));
    Cipher.Encode(aText[Low(aText)], Data[Low(Data)], Length(Data));

    Mac := BytesOf(Cipher.CalcMAC);
    Result := StringOf(ValidFormat(TextFormat).Encode(Salt + Data + Mac));
  finally
    Cipher.Free;
    ProtectBytes(Salt);
    ProtectBytes(Pass);
    ProtectBytes(Data);
    ProtectBytes(Mac);
  end;
end;

end.