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

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

 Chilkat Perl Module Downloads for Windows, Linux, and MAC OS X

use chilkat();

$key = new chilkat::CkSshKey();

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

print "Done!" . "\n";