Letting users post referral url to facebook (laravel-5)

I'm trying to let users post their referral url on facebook. I pass a $url variable to the views and I put this :

<div
  class="fb-like"
  data-share="true"
  data-href= "<?php isset($url)? $url:null ?>"
  data-width="450"
  data-show-faces="true">
</div>

the url is suppose to be something like:

'http://ift.tt/1RnE9fd'

But instead what gets shared is:

'http://ift.tt/1j6U3zn'

which is the page the user is sharing from.

I tried passing this:

<meta property="og:url" content="{{$url}}" />

the facebook debugger said og:url is not provided.

via Chebli Mohamed