DELPHI - Criptografar e Decriptografar String (AES-256) - Encrypt and Decrypt String (AES-256)

Segue Unit para Encriptar ou Decriptar String.

unit uCriptografia;

interface

uses
  uTPLb_CryptographicLibrary, uTPLb_Codec, //Componentes LockBox
  System.SysUtils //FreeAndNil
  ;

const
  Key = 'ValorChave'; //Valor chave para Encriptar e Decriptar(Use um seu)


  function encriptar(const Valor :String):String;
  function decriptar(const Valor :String):String;

implementation

function encriptar(const Valor :String):String;
var
  CryptoLib: TCryptographicLibrary;
  Codec: TCodec;
begin
  Result := '';
  CryptoLib := TCryptographicLibrary.Create(nil);
  Codec := TCodec.Create(nil);
  try
    Codec.CryptoLibrary := CryptoLib;
    Codec.StreamCipherId := 'native.StreamToBlock';
    Codec.BlockCipherId := 'native.AES-256'; //Encriptação AES 256 bits
    Codec.ChainModeId := 'native.CBC';

    Codec.Reset;
    Codec.Password := Key; //Atribuindo a chave para a Criptografia
    Codec.EncryptString(Valor, Result, TEncoding.UTF8);
  finally
    FreeAndNil(CryptoLib);
    FreeAndNil(Codec);
  end;
end;

function decriptar(const Valor :String):String;
var
  CryptoLib: TCryptographicLibrary;
  Codec: TCodec;
begin
  Result := '';
  CryptoLib := TCryptographicLibrary.Create(nil);
  Codec := TCodec.Create(nil);
  try
    Codec.CryptoLibrary := CryptoLib;
    Codec.StreamCipherId := 'native.StreamToBlock';
    Codec.BlockCipherId := 'native.AES-256'; //Encriptação AES 256 bits
    Codec.ChainModeId := 'native.CBC';

    Codec.Reset;
    Codec.Password := Key; //Atribuindo a chave para Decriptografia
    Codec.DecryptString(Result, Valor, TEncoding.UTF8);
  finally
    FreeAndNil(CryptoLib);
    FreeAndNil(Codec);
  end;
end;

end.

Para usar é só declarar a Unit(uCriptografia) nas Uses do projeto e chamar as funções diretamente.