(VBScript) 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

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

' 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")
set privKey = CreateObject("Chilkat.PrivateKey")

' This loads an ECDSA key from an unencrypted PEM file (no password required).
success = privKey.LoadAnyFormatFile("qa_data/ecc/openssl_ecc_privKey.pem","")
If (success = 0) Then
    outFile.WriteLine(privKey.LastErrorText)
    WScript.Quit
End If

' The key type should be "ecc" to indicate an EC key.
outFile.WriteLine("key type = " & privKey.KeyType)

' What is the size of the private key in bits?
outFile.WriteLine("size in bits = " & privKey.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")
set sbPubKeyHex = CreateObject("Chilkat.StringBuilder")
privKeyHex = privKey.GetRawHex(sbPubKeyHex)

' If the private key size in bits is 256, then we should have a 32-byte key (a 64 character hex string).
outFile.WriteLine("private key = " & privKeyHex)

' The public key is composed of the "x" and "y" parts, and is composed like this:  04||HEX(x)||HEX(y)
outFile.WriteLine("public key = " & sbPubKeyHex.GetAsString())

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

outFile.Close