(PowerShell) Generate ECDSA Key and Get Details as XML

Demonstrates how to generate an ECDSA key and gets the parts as XML.

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

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Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

# This requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

$ecc = New-Object Chilkat.Ecc

# Generate a random ECC private key on the secp256k1 curve.
# Chilkat also supports other curves, such as secp384r1, secp521r1, and secp256r1.

# Create a Fortuna PRNG and seed it with system entropy.
# This will be our source of random data for generating the ECC private key.
$fortuna = New-Object Chilkat.Prng
$entropy = $fortuna.GetEntropy(32,"base64")
$success = $fortuna.AddEntropy($entropy,"base64")

$privKey = New-Object Chilkat.PrivateKey
$success = $ecc.GenKey("secp256k1",$fortuna,$privKey)
if ($success -ne $true) {
    $($ecc.LastErrorText)
    exit
}

# An EC private key has this ASN.1
# ECPrivateKey ::= SEQUENCE {
#     version        INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
#     privateKey     OCTET STRING,
#     parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
#     publicKey  [1] BIT STRING OPTIONAL (This is the ANSI X9.63 public key format.)

$asn = New-Object Chilkat.Asn
$success = $asn.LoadEncoded($privKey.GetPkcs1ENC("base64"),"base64")
if ($success -ne $true) {
    $($asn.LastErrorText)
    exit
}

$xml = New-Object Chilkat.Xml
$xml.LoadXml($asn.AsnToXml())

$($xml.GetXml())

# The XML looks like this:
# <?xml version="1.0" encoding="utf-8" ?>
# <sequence>
#     <int>01</int>
#     <octets>JgJvBG+3wletkJab8iXAkpz0O8/AgWZSpkYVcB7SpnU=</octets>
#     <contextSpecific tag="0" constructed="1">
#         <oid>1.3.132.0.10</oid>
#     </contextSpecific>
# </sequence>

# The 32-byte private key is in the octets..
# Get it as hex.
$crypt = New-Object Chilkat.Crypt2
$privKeyHex = $crypt.ReEncode($xml.GetChildContent("octets"),"base64","hex")

$("EC private key as hex = " + $privKeyHex)