U2F Login for WordPress – OPENSSL_VERSION_NUMBER Undefined

While looking to get this working:, I was seeing errors in the http logs referring to OPENSSL_VERSION_TEXT. These were being generated by the following lines in the u2f.php file:

After running a few more tests, it seemed that this PHP Constant should have been defined, but was not. Goggling didn’t provide any quick answers, but I soon worked it out for myself.

In the php.ini file (under arch in /etc/php/), uncomment the line: “” and restart httpd. Once the extension is enabled, the Constant is then available.

In the end I did not use this plugin, I was unable to register my Yubikeys. The plugin seems to have been superseded by this one: In order to have the ability to use U2F login using this plugin, the extension has to be enabled; otherwise, the U2F login option is not available.

Getting PiGlow working on Arch Linux with Raspberry Pi 2

It initially seemed like a trivial task; after all getting the PiGLow working under Raspian was very simple!

But under Arch the method is significantly different…So, after digging about, getting all the pieces together – this is what I have and it works!

Now to get this to run on start-up…