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PHP Extension

Generate an RSA Key and Save to Encrypted PEM

See more RSA Examples

Demonstrates how to generate an RSA key and save to an encrypted PEM file.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

$success = false;

$rsa = new CkRsa();

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

$password = 'secret';
// Saving to a relative path (from the current working directory of the process).
$path = 'rsaKeys/myTestRsaPrivate.pem';
// Encrypt the PEM using 256-bit AES encryption.
$privKey->put_Pkcs8EncryptAlg('aes256');
$success = $privKey->SavePkcs8EncryptedPemFile($password,$path);
if ($success == false) {
    print $privKey->lastErrorText() . "\n";
    exit;
}

// image

// We can also save the public key.
// There is no need to encrypt public keys.
$pubKey = new CkPublicKey();
$privKey->ToPublicKey($pubKey);

$path = 'rsaKeys/myTestRsaPublic.pem';
// Choose PKCS1 or PKCS8
// We'll choose PKCS8.
$preferPkcs1 = false;
$success = $pubKey->SavePemFile($preferPkcs1,$path);
if ($success == false) {
    print $pubKey->lastErrorText() . "\n";
    exit;
}

// image

print 'Success.' . "\n";

?>