Pascal (Lazarus/Delphi)

Apple Keychain - Create RSA Signature

See more Apple Keychain Examples

Using an RSA private key stored in the Apple Keychain, create a signature by signing the SHA-256 hash of the provided string, then return the signature encoded in Base64 format.

Note: This example requires Chilkat v10.0.0 or greater.

Pascal (Lazarus/Delphi)

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.Cert,
  Chilkat.Rsa;

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

procedure RunDemo;
var
  success: Boolean;
  cert: TCert;
  rsa: TRsa;
  sigBase64: string;

begin
  success := False;

  //  This example requires the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  cert := TCert.Create;

  //  On MacOS and iOS, the LoadByCommonName function will search the Apple Keychain for the matching certificate.

  //  A digital certificate's Common Name (CN) is a field in the certificate that specifies the name of the entity the 
  //  certificate is issued to. It is often used to identify the domain name, hostname, or organization the certificate represents. 

  //  For example:
  //  - In an SSL/TLS certificate for a website, the CN typically contains the domain name (e.g., "www.example.com").
  //  - For certificates representing individuals or organizations, the CN might include the person's name or the organization's name.

  //  The CN is part of the certificate's Subject field and is crucial for verifying that the certificate corresponds 
  //  to the intended entity, especially in SSL/TLS communications.

  success := cert.LoadByCommonName('Example, Inc.');
  if (success = False) then
    begin
      WriteLn(cert.LastErrorText);
      Exit;
    end;

  rsa := TRsa.Create;
  success := rsa.SetX509Cert(cert,True);
  if (success = False) then
    begin
      WriteLn(rsa.LastErrorText);
      Exit;
    end;

  //  Generate an RSA signature by signing the SHA-256 hash of the provided string, 
  //  then return the signature encoded in Base64 format.
  rsa.EncodingMode := 'base64';
  sigBase64 := rsa.SignStringENC('to be signed','sha256');
  if (rsa.LastMethodSuccess = False) then
    begin
      WriteLn(rsa.LastErrorText);
      Exit;
    end;

  WriteLn('RSA Signature:');
  WriteLn(sigBase64);


  cert.Free;
  rsa.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.