Decrypt a JWE with a Private Key

See more JSON Web Encryption (JWE) Examples

Demonstrates Jwe.SetPrivateKey, which sets the private key used to decrypt a recipient of a loaded JWE.

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.PrivateKey,
  Chilkat.Jwe;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  jwe: TJwe;
  jweCompact: string;
  privKey: TPrivateKey;
  content: string;

begin
  success := False;

  jwe := TJwe.Create;

  //  Load the JWE compact serialization to be decrypted.
  jweCompact := 'eyJhbGciOiJBMjU2S1ciLCJlbmMiOiJBMjU2R0NNIn0.<...>.<iv>.<ciphertext>.<tag>';
  success := jwe.LoadJwe(jweCompact);
  if (success = False) then
    begin
      WriteLn(jwe.LastErrorText);
      Exit;
    end;

  //  The file path is relative to the application's current working directory.  An absolute path
  //  may also be used.  Supply the path appropriate to your own environment.
  //  Load the recipient's private key.
  privKey := TPrivateKey.Create;
  success := privKey.LoadPemFile('qa_data/recipient_privkey.pem');
  if (success = False) then
    begin
      WriteLn(privKey.LastErrorText);
      Exit;
    end;

  //  Set the private key used to decrypt recipient 0.
  success := jwe.SetPrivateKey(0,privKey);
  if (success = False) then
    begin
      WriteLn(jwe.LastErrorText);
      Exit;
    end;

  content := jwe.Decrypt(0,'utf-8');
  if (jwe.LastMethodSuccess = False) then
    begin
      WriteLn(jwe.LastErrorText);
      Exit;
    end;
  WriteLn(content);


  jwe.Free;
  privKey.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.