Delphi ActiveX

Manually Duplicate SetSecretKeyViaPassword

Demonstrates how to duplicate the password string to binary secret key computation of SetSecretKeyViaPassword. Delphi ActiveX

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
crypt: TChilkatCrypt2;
password: WideString;
sb: TChilkatStringBuilder;
passwordBase64: WideString;

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

crypt := TChilkatCrypt2.Create(Self);

// The password string is transformed to a binary secret key by computing the 
// MD5 digest (of the utf-8 password) to obtain 16 bytes.  
// If the KeyLength is greater than 16 bytes, then the MD5 digest of the Base64 encoding 
// of the utf-8 password is added.  A max of 32 bytes of key material is generated, and 
// this is truncated to the actual KeyLength required.

crypt.CryptAlgorithm := 'aes';
crypt.KeyLength := 256;

password := 'this is my password';
crypt.SetSecretKeyViaPassword(password);

// Examine the resulting SecretKey in hex:
Memo1.Lines.Add('Computed Secret Key = ' + crypt.GetEncodedKey('hex'));

// Now perform the same computation manually:
sb := TChilkatStringBuilder.Create(Self);

crypt.HashAlgorithm := 'md5';
crypt.Charset := 'utf-8';
crypt.EncodingMode := 'hex';
sb.Append(crypt.HashStringENC(password));

passwordBase64 := crypt.EncodeString(password,'utf-8','base64');
sb.Append(crypt.HashStringENC(passwordBase64));

Memo1.Lines.Add('Manually Computed = ' + sb.GetAsString());

// The output is:
// Computed Secret Key = 210D53992DFF432EC1B1A9698AF9DA16C7E90518F90E24828F78EC9E0A413B36
// Manually Computed = 210D53992DFF432EC1B1A9698AF9DA16C7E90518F90E24828F78EC9E0A413B36
end;