(PHP Extension) Generate RSA Key and return Base64 PKCS8 Private Key

Demonstrates how to generate a new 2048-bit RSA private key and returns the Base64 encoded PKCS8 representation of the private key.

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux

<?php

include("chilkat.php");
// Use "chilkat_9_5_0.php" for versions of Chilkat < 10.0.0

$rsa = new CkRsa();

// Generate a 2048-bit key.  Chilkat RSA supports
// key sizes ranging from 512 bits to 8192 bits.
$success = $rsa->GenerateKey(2048);
if ($success != true) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

// privKey is a CkPrivateKey
$privKey = $rsa->ExportPrivateKeyObj();

// Get the private key in PKCS8 Base64 format
$privKeyPkcs8Base64 = $privKey->getPkcs8ENC('base64');

// The key in base64 format will start similar to this:
// MIIEvAIBADANBgkqhkiG9w0BA...
print $privKeyPkcs8Base64 . "\n";

?>