Delphi DLL

Load EC Public Key from X,Y Values

See more ECC Examples

Demonstrates how to load an EC public key from X and Y values. Delphi DLL

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
x: PWideChar;
y: PWideChar;
json: HCkJsonObject;
pubkey: HCkPublicKey;

begin
success := False;

// We have the following x and y values in base64 (for an EC point on the P-256 curve).
x := 'Dn7uB1O7kgk74G6qfQwFJESeDnxO6lLjGZFWZJE16tw';
y := 'iOWA5DInzK6nuUGvHJbMVq1Dpj248FqSV2teN3HzmhU';

// Build a JWK that looks like this:

// {
//   "kty": "EC",
//   "crv": "P-256",
//   "x": "Dn7uB1O7kgk74G6qfQwFJESeDnxO6lLjGZFWZJE16tw",
//   "y": "iOWA5DInzK6nuUGvHJbMVq1Dpj248FqSV2teN3HzmhU"
// }

json := CkJsonObject_Create();
CkJsonObject_UpdateString(json,'kty','EC');
CkJsonObject_UpdateString(json,'crv','P-256');
CkJsonObject_UpdateString(json,'x',x);
CkJsonObject_UpdateString(json,'y',y);

// Load from the JWK.
pubkey := CkPublicKey_Create();
success := CkPublicKey_LoadFromString(pubkey,CkJsonObject__emit(json));
if (success = False) then
  begin
    Memo1.Lines.Add(CkPublicKey__lastErrorText(pubkey));
    Exit;
  end;

Memo1.Lines.Add('Success.');

CkJsonObject_Dispose(json);
CkPublicKey_Dispose(pubkey);

end;