Using a .NET .snk Key File for RSA Encryption

Demonstrates how to load and use a .NET .snk key file for RSA encryption. SNK files are created by the Microsoft .NET Strong Name Tool (Sn.exe).

Download Chilkat RSA ActiveX

<?php

$rsa = new COM("Chilkat.Rsa");

$success = $rsa->UnlockComponent('Anything for 30-day trial');
if ($success != true) {
    print 'RSA component unlock failed' . "\n";
    exit;
}

//  Load a public/private key pair from a .snk key file.
$xmlKey = $rsa->snkToXml('chilkat2.snk');

print $xmlKey . "\n";

//  The xmlKey contains both public and private keys.
//  Import either the public or private for encrypting or
//  decrypting.
$rsa->ImportPrivateKey($xmlKey);

$bUsePrivateKey = true;
$encryptedText = $rsa->encryptStringENC('Hello World!',$bUsePrivateKey);

print $encryptedText . "\n";

//  Now decrypt with the public key:
$rsa->ImportPublicKey($xmlKey);
$bUsePrivateKey = false;
$decryptedText = $rsa->decryptStringENC($encryptedText,$bUsePrivateKey);

print $decryptedText . "\n";

//  Note: We could have just as well encrypted using the public key
//  and decrypted using the private key.

?>