(PHP ActiveX) Generate ECDSA Key and Get Details as XML

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

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows Note: The php_com_dotnet.dll may need to be enabled inside of php.ini.

<?php

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

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Ecc')
$ecc = new COM("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.
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Prng')
$fortuna = new COM("Chilkat.Prng");
$entropy = $fortuna->getEntropy(32,'base64');
$success = $fortuna->AddEntropy($entropy,'base64');

// privKey is a Chilkat.PrivateKey
$privKey = $ecc->GenEccKey('secp256k1',$fortuna);
if ($ecc->LastMethodSuccess != 1) {
    print $ecc->LastErrorText . "\n";
    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.)

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Asn')
$asn = new COM("Chilkat.Asn");
$success = $asn->LoadEncoded($privKey->getPkcs1ENC('base64'),'base64');
if ($success != 1) {
    print $asn->LastErrorText . "\n";
    exit;
}

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Xml')
$xml = new COM("Chilkat.Xml");
$xml->LoadXml($asn->asnToXml());

print $xml->getXml() . "\n";

// 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.
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Crypt2')
$crypt = new COM("Chilkat.Crypt2");
$privKeyHex = $crypt->reEncode($xml->getChildContent('octets'),'base64','hex');

print 'EC private key as hex = ' . $privKeyHex . "\n";


?>