(Visual FoxPro) Get EC Public Key from EC Private Key

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

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL lnSuccess
LOCAL loPrivKey
LOCAL loPubKey

lnSuccess = 0

* 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-----

loPrivKey = CreateObject('Chilkat.PrivateKey')
lnSuccess = loPrivKey.LoadPemFile("qa_data/ecc/secp256r1-key-pkcs8.pem")
IF (lnSuccess = 0) THEN
    ? loPrivKey.LastErrorText
    RELEASE loPrivKey
    CANCEL
ENDIF

* Get the public key.
loPubKey = CreateObject('Chilkat.PublicKey')
loPrivKey.ToPublicKey(loPubKey)

* Save the public key to a PEM file.
lnSuccess = loPubKey.SavePemFile(0,"qa_data/ecc/secp256r1-pubkey.pem")
IF (lnSuccess = 0) THEN
    ? loPubKey.LastErrorText
    RELEASE loPrivKey
    RELEASE loPubKey
    CANCEL
ENDIF

* 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-----

? "Success."

RELEASE loPrivKey
RELEASE loPubKey