(Visual FoxPro) Get an EC Key in Raw Hex Format

Demonstrates how to get the private and public key parts of an EC (ECDSA) key in lowercase hex formmat.

Note: This example requires Chilkat v9.5.0.83 or greater.

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

LOCAL loPrivKey
LOCAL lnSuccess
LOCAL loSbPubKeyHex
LOCAL lcPrivKeyHex

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

* Load an EC key from some format..
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.PrivateKey')
loPrivKey = CreateObject('Chilkat.PrivateKey')

* This loads an ECDSA key from an unencrypted PEM file (no password required).
lnSuccess = loPrivKey.LoadAnyFormatFile("qa_data/ecc/openssl_ecc_privKey.pem","")
IF (lnSuccess = 0) THEN
    ? loPrivKey.LastErrorText
    RELEASE loPrivKey
    CANCEL
ENDIF

* The key type should be "ecc" to indicate an EC key.
? "key type = " + loPrivKey.KeyType

* What is the size of the private key in bits?
? "size in bits = " + STR(loPrivKey.BitLength)

* Get the private and public EC key parts in raw hex format:
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.StringBuilder')
loSbPubKeyHex = CreateObject('Chilkat.StringBuilder')
lcPrivKeyHex = loPrivKey.GetRawHex(loSbPubKeyHex)

* If the private key size in bits is 256, then we should have a 32-byte key (a 64 character hex string).
? "private key = " + lcPrivKeyHex

* The public key is composed of the "x" and "y" parts, and is composed like this:  04||HEX(x)||HEX(y)
? "public key = " + loSbPubKeyHex.GetAsString()

* Sample output:
* key type = ecc
* size in bits = 256
* private key = ced36f2ba3332be439f79143d69937fc52494cd38e45243c3ea05db183919f1b
* public key = 045b4edcd501831740895f5907feabb71587076a6314d9d5141f9f8c33a478b8ce08b8dfd2a091eb6355803d7e729876c790bc0b176f2015f3bb103813753f676a

RELEASE loPrivKey
RELEASE loSbPubKeyHex