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Delphi DLL

RSA Signature SHA256withRSA, iso-8859-1, base64

See more RSA Examples

RSA sign the iso-8859-1 byte representation of a string with SHA256withRSA, and return the signature in the base64 encoding.

Chilkat Delphi DLL Downloads

Delphi DLL
uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, PrivateKey, Rsa;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
privKey: HCkPrivateKey;
rsa: HCkRsa;
originalData: PWideChar;
sigBase64: PWideChar;

begin
success := False;

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

// This example will duplicate the following Java code:
// 
// Signature sign = Signature.getInstance("SHA256withRSA");
// sign.initSign(privateKey);
// sign.update(original.getBytes(Charset.forName("ISO-8859-1")));
// 
// ...
// byte[] resultado = sign.sign();
// sello = encodeByteArrayToBase64(resultado);
// 

// Load an RSA private key for signing.
// You can load any format file.  This example loads a .pem, but you can provide path to any type of file holding a private key.
privKey := CkPrivateKey_Create();
success := CkPrivateKey_LoadAnyFormatFile(privKey,'qa_data/pem/rsa_passwd.pem','passwd');
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(privKey));
    Exit;
  end;

rsa := CkRsa_Create();
CkRsa_UsePrivateKey(rsa,privKey);

originalData := 'This is the string to be hashed an RSA signed.';

// Indicate that we want the iso-8859-1 byte representation of the string to be signed
CkRsa_putCharset(rsa,'iso-8859-1');

// We want the RSA signature in base64 format
CkRsa_putEncodingMode(rsa,'base64');

sigBase64 := CkRsa__signStringENC(rsa,originalData,'sha256');
Memo1.Lines.Add(sigBase64);

CkPrivateKey_Dispose(privKey);
CkRsa_Dispose(rsa);

end;