Currently, all OpenSSL Functions defined in PHP only utilize the PEM format. Use the following code to convert from DER to PEM and PEM to DER.
<?php
$pem_data = file_get_contents($cert_path.$pem_file);
$pem2der = pem2der($pem_data);
$der_data = file_get_contents($cert_path.$der_file);
$der2pem = der2pem($der_data);
function pem2der($pem_data) {
$begin = "CERTIFICATE-----";
$end = "-----END";
$pem_data = substr($pem_data, strpos($pem_data, $begin)+strlen($begin));
$pem_data = substr($pem_data, 0, strpos($pem_data, $end));
$der = base64_decode($pem_data);
return $der;
}
function der2pem($der_data) {
$pem = chunk_split(base64_encode($der_data), 64, "\n");
$pem = "-----BEGIN CERTIFICATE-----\n".$pem."-----END CERTIFICATE-----\n";
return $pem;
}
?>
