PHP ActiveX

Convert RSA Private Key to Public Key

See more RSA Examples

Demonstrates how to get a public RSA key from a private RSA key. PHP ActiveX

<?php

$success = 0;

$privKey = new COM("Chilkat.PrivateKey");

// Step 1: Load the private key from a source.
// (Chilkat can load private keys from all types of formats, and from in-memory bytes or encoded strings.
// see the online reference documentation for more options.)
$success = $privKey->LoadPemFile('qa_data/pem/VP_Private.pem');
if ($success == 0) {
    print $privKey->LastErrorText . "\n";
    exit;
}

// Step 2: Get the public key object from the private key object.
$pubKey = new COM("Chilkat.PublicKey");
$privKey->ToPublicKey($pubKey);

// Step 3: Save the public key in a desired format. 
// (Chilkat can load or save public and private keys in many different formats.  See
// the online reference documentation for more options.)

// Saves to a PKCS8 PEM file.
$bPreferPkcs1 = 0;
$success = $pubKey->SavePemFile($bPreferPkcs1,'qa_data/pem/VP_Public.pem');
if ($pubKey->LastMethodSuccess == 0) {
    print $pubKey->LastErrorText . "\n";
    exit;
}

print 'Extracted and saved public key from private key.' . "\n";

?>