PHP Extension

Convert Let's Encrypt PEM Files to a PFX

See more PFX/P12 Examples

Demonstrates how to convert the .pem files provided by Let's Encrypt to a single PFX. PHP Extension

<?php

include("chilkat.php");

$success = false;

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

// Let's Encrypt provides four .pem files
// 1. fullchain.pem
// 2. privkey.pem
// 3. cert.pem
// 4. chain.pem

// The cert.pem and chain.pem are redundant. 
// The fullchain.pem is composed of the cert.pem and chain.pem.

// To convert the PEM's to a single .pfx, we don't need the redundant data.
// The privkey.pem and fullchain.pem provide the required data.
// We can ignore cert.pem and chain.pem (because those certs are already found in fullchain.pem).

// We need a single .pem file that contains both the private key, the cert,
// and the certs in the chain of authentication.
// Let's combine priveky.pem and fullchain.pem into a single .pem

$sbPem = new CkStringBuilder();
$success = $sbPem->LoadFile('qa_data/pem/lets_encrypt/privkey.pem','utf-8');
if ($success == false) {
    print 'Failed to load privkey.pem' . "\n";
    exit;
}

// To be safe, append a blank line..
$sbPem->AppendLine('',false);

$sbFullChainPem = new CkStringBuilder();
$success = $sbFullChainPem->LoadFile('qa_data/pem/lets_encrypt/fullchain.pem','utf-8');
if ($success == false) {
    print 'Failed to load fullchain.pem' . "\n";
    exit;
}

// Append the full cert chain PEM to the private key PEM.
$sbPem->AppendSb($sbFullChainPem);

// Load the combined PEM into a Chilkat PFX object.
$pfx = new CkPfx();
$success = $pfx->LoadPem($sbPem->getAsString(),'no password required');
if ($success == false) {
    print $pfx->lastErrorText() . "\n";
    exit;
}

// Write the PFX w/ a password.
$pfxPassword = 'secret';
$success = $pfx->ToFile($pfxPassword,'qa_output/sample.pfx');
if ($success == false) {
    print $pfx->lastErrorText() . "\n";
    exit;
}

print 'Success!' . "\n";

?>