(PHP ActiveX) Convert PuTTY Private Key (ppk) to OpenSSH (pem)

Convert a PuTTY format private key file (.ppk) to OpenSSH (.pem).

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows Note: The php_com_dotnet.dll may need to be enabled inside of php.ini.

<?php

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.SshKey')
$key = new COM("Chilkat.SshKey");

// Load an unencrypted or encrypted PuTTY private key.

// If  your PuTTY private key is encrypted, set the Password
// property before calling FromPuttyPrivateKey.
// If your PuTTY private key is not encrypted, it makes no diffference
// if Password is set or not set.
$key->Password = 'secret';

// First load the .ppk file into a string:

$keyStr = $key->loadText('putty_private_key.ppk');

// Import into the SSH key object:
$success = $key->FromPuttyPrivateKey($keyStr);
if ($success != 1) {
    print $key->LastErrorText . "\n";
    exit;
}

// Convert to an encrypted or unencrypted OpenSSH key.

// First demonstrate converting to an unencrypted OpenSSH key

$bEncrypt = 0;
$unencryptedKeyStr = $key->toOpenSshPrivateKey($bEncrypt);
$success = $key->SaveText($unencryptedKeyStr,'unencrypted_openssh.pem');
if ($success != 1) {
    print $key->LastErrorText . "\n";
    exit;
}

// Save to an encrypted OpenSSH PEM file:

$bEncrypt = 1;
$key->Password = 'myPassword';
$encryptedKeyStr = $key->toOpenSshPrivateKey($bEncrypt);
$success = $key->SaveText($encryptedKeyStr,'encrypted_openssh.pem');
if ($success != 1) {
    print $key->LastErrorText . "\n";
    exit;
}

print 'Done!' . "\n";

?>