(PHP ActiveX) Working with PEM Encrypted Private Keys

Demonstrates how to load and save PEM encrypted private keys.

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

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

$success = 0;

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

$success = 0;

$pem = new COM("Chilkat.Pem");

$pemPassword = 'secret';

// To load a PEM file containing encrypted private keys, simply
// provide the password.
$success = $pem->LoadPemFile('/Users/chilkat/testData/pem/pemContainingEncryptedPrivateKeys.pem',$pemPassword);
if ($success == 0) {
    print $pem->LastErrorText . "\n";
    exit;
}

$fac = new COM("Chilkat.FileAccess");
$pemText = $fac->readEntireTextFile('/Users/chilkat/testData/pem/pemContainingEncryptedPrivateKeys.pem',$pemPassword);

// To load a PEM from a string, call LoadPem instead of LoadPemFile:
$success = $pem->LoadPem($pemText);
if ($success == 0) {
    print $pem->LastErrorText . "\n";
    exit;
}

// A few notes:
// The PEM may contain both private keys and certificates (or anything else).
// The password is utilized for whatever content in the PEM is encrypted.  
// It is OK to have both encrypted and non-encrypted content within a given PEM.

// PEM private keys can be encrypted in different formats.  The LoadPem and LoadPemFile
// methods automatically handle the different formats.
// One format is PKCS8 and is indicated by this delimiter within the PEM:

// -----BEGIN ENCRYPTED PRIVATE KEY-----
// MIICoTAbBgkqhkiG9w0BBQMwDgQIfdD0zv24lgkCAggABIICgE0PdHJmRbNs6cBX
// ...

// Another format, we'll call "passphrase" looks like this in the PEM:
// -----BEGIN RSA PRIVATE KEY-----
// Proc-Type: 4,ENCRYPTED
// DEK-Info: DES-EDE3-CBC,A4215544D11C5D0C
// 
// paqy9XRexcSjurHfG0xhCaUD0HrvIdhuC0CbRxxxeMlkLaV6+uT80rBxt2AaibWG
// ...

// Show the bit length of each private key:

$numPrivateKeys = $pem->NumPrivateKeys;
if ($numPrivateKeys == 0) {
    print (('Error: Expected the PEM to contain private keys.')) . "\n";
    exit;
}

$privKey = new COM("Chilkat.PrivateKey");
for ($i = 1; $i <= $numPrivateKeys; $i++) {
    $pem->PrivateKeyAt($i - 1,$privKey);
    print $i . ': ' . $privKey->BitLength . ' bits' . "\n";
}


?>