How to properly generate a WSSE Password Digest in PHP

I'm looking at building a REST API in Symfony2, and in their Custom Authentication Provider they show how to build a WSSE authentication system, which should be fine for what I need to do. I'm going to start off by building and testing the API through cURL, so I need to be able to quickly generate the headers. I found a JS generator that showed the headers I would need.

From what I read, the Password Digest should be a base64 encoded SHA1 of the nonce, timestamp, and user password concatenated together in that order. I started with the following data:

$nonce = '4c5625ec7af5bdff';
$timestamp = '2013-04-03T04:46:19Z';
$password = 'mypass';

and generated the digest:

$digest = base64_encode(sha1($nonce.$timestamp.$password));

What I don't understand is that the $digest variable is now set to YTgxMDUzOWQzMDBiZmU1MmI2NWQ0YjYwNDc3ZmY5OWI3MmVlZTQyNA==, but the sample PasswordDigest from the JS generator comes up as qBBTnTAL/lK2XUtgR3/5m3Lu5CQ=. I must be missing a step somewhere, but I'm not sure what it is.

Solution

Looks like I need to use the binary SHA1 result, not the hex representation. My digest should look like this:

$digest = base64_encode(sha1($nonce.$timestamp.$password, true));