Delphi DLL Requires Chilkat v11.0.0+

Get EC Public Key from EC Private Key

See more ECC Examples

Demonstrates how to get an EC public key from an EC private key. Delphi DLL

var
success: Boolean;
privKey: HCkPrivateKey;
pubKey: HCkPublicKey;

begin
success := False;

//  We have an ECC private key...
//  The contents of the private key PEM file look like this:

//  	-----BEGIN PRIVATE KEY-----
//  	MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQg3J8q/24D1sEKGdP9
//  	72MGYElLGpw/a56Y3t6pfON3uhShRANCAATlSmoizyhAwoYZAOuFBATl07/1RR54
//  	a1Dzfm16grxJe666AGKR+bSs24hk7TEpaeCTvT8YOOM3l+xKFg7zq6Q9
//  	-----END PRIVATE KEY-----

privKey := CkPrivateKey_Create();
success := CkPrivateKey_LoadPemFile(privKey,'qa_data/ecc/secp256r1-key-pkcs8.pem');
if (success = False) then
  begin
    Memo1.Lines.Add(CkPrivateKey__lastErrorText(privKey));
    Exit;
  end;

//  Get the public key.
pubKey := CkPublicKey_Create();
CkPrivateKey_ToPublicKey(privKey,pubKey);

//  Save the public key to a PEM file.
success := CkPublicKey_SavePemFile(pubKey,False,'qa_data/ecc/secp256r1-pubkey.pem');
if (success = False) then
  begin
    Memo1.Lines.Add(CkPublicKey__lastErrorText(pubKey));
    Exit;
  end;

//  The contents of the ECC public key PEM file look like this:

//  	-----BEGIN PUBLIC KEY-----
//  	MIIBSzCCAQMGByqGSM49AgEwgfcCAQEwLAYHKoZIzj0BAQIhAP////8AAAABAAAA
//  	AAAAAAAAAAAA////////////////MFsEIP////8AAAABAAAAAAAAAAAAAAAA////
//  	///////////8BCBaxjXYqjqT57PrvVV2mIa8ZR0GsMxTsPY7zjw+J9JgSwMVAMSd
//  	NgiG5wSTamZ44ROdJreBn36QBEEEaxfR8uEsQkf4vOblY6RA8ncDfYEt6zOg9KE5
//  	RdiYwpZP40Li/hp/m47n60p8D54WK84zV2sxXs7LtkBoN79R9QIhAP////8AAAAA
//  	//////////+85vqtpxeehPO5ysL8YyVRAgEBA0IABOVKaiLPKEDChhkA64UEBOXT
//  	v/VFHnhrUPN+bXqCvEl7rroAYpH5tKzbiGTtMSlp4JO9Pxg44zeX7EoWDvOrpD0=
//  	-----END PUBLIC KEY-----

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

CkPrivateKey_Dispose(privKey);
CkPublicKey_Dispose(pubKey);