(PHP Extension) Generate an RSA Key and Get as Base64 DER

Demonstrates how to generate a 2048-bit RSA key and return the public and private parts as unencrypted Base64 encoded DER.

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

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<?php

include("chilkat.php");

$success = false;

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

$rsa = new CkRsa();

// Generate a 2048-bit key.
$privKey = new CkPrivateKey();
$success = $rsa->GenKey(2048,$privKey);
if ($success == false) {
    print $rsa->lastErrorText() . "\n";
    exit;
}

// Get the public part of the key.
$pubKey = new CkPublicKey();
$privKey->ToPublicKey($pubKey);

// There are two possible formats for representing the RSA public key 
// in ASN.1 (DER).  The possible formats are PKCS1 and PKCS8.
// We can get either by setting bChoosePkcs1 to true or false.
$bChoosePkcs1 = true;
$pubKeyBase64Der = $pubKey->getEncoded($bChoosePkcs1,'base64');
print 'Public Key Base64 DER:' . "\n";
print $pubKeyBase64Der . "\n";

// Get the private key as Base64 DER:
// We can get PKCS1 or PKCS8, but with different methods:
$privKeyPkcs1 = $privKey->getPkcs1ENC('base64');
print 'Private Key PKCS1 Base64 DER:' . "\n";
print $privKeyPkcs1 . "\n";

$privKeyPkcs8 = $privKey->getPkcs8ENC('base64');
print 'Private Key PKCS8 Base64 DER:' . "\n";
print $privKeyPkcs8 . "\n";

?>