Betterer IP address detection.

[jaswrks]

• Improves IP address detection.

• Supports CloudFlare IP forwarding.

• Supports multiple IPs in a single header.

• The following lookup order is used by ZenCache. We use the first public IP address found in these headers, starting from the top and working down.

  'HTTP_CF_CONNECTING_IP',
  'HTTP_CLIENT_IP',
  'HTTP_X_FORWARDED_FOR',
  'HTTP_X_FORWARDED',
  'HTTP_X_CLUSTER_CLIENT_IP',
  'HTTP_FORWARDED_FOR',
  'HTTP_FORWARDED',
  'HTTP_VIA',
  'REMOTE_ADDR',
  

• Supports a filter in case a site owner would like to revert to the old behavior.

  Create this directory and file:
  /wp-content/mu-plugins/zc-prioritize-remote-addr.php

  <?php
  add_filter('zencache\\share::current_ip_prioritize_remote_addr', '__return_true');

[jaswrks]

There is also a filter that can be used to customize the lookup order and/or add/remove sources that are searched when looking for the current IP address.

From the ZenCache source code we find this:

$sources = array(
  'HTTP_CF_CONNECTING_IP',
  'HTTP_CLIENT_IP',
  'HTTP_X_FORWARDED_FOR',
  'HTTP_X_FORWARDED',
  'HTTP_X_CLUSTER_CLIENT_IP',
  'HTTP_FORWARDED_FOR',
  'HTTP_FORWARDED',
  'HTTP_VIA',
  'REMOTE_ADDR',
);
$sources = $this->apply_filters(__METHOD__.'_sources', $sources);

---

So to modify the list of sources create this directory and file:

/wp-content/mu-plugins/zc-ip-sources.php

<?php
add_filter('zencache\\share::current_ip_sources', function($sources)
{
    // A source is an array key in the `$_SERVER` superglobal.
    return array(
     'HTTP_CF_CONNECTING_IP',
     'HTTP_CLIENT_IP',
     'HTTP_X_FORWARDED_FOR',
     'HTTP_X_FORWARDED',
     'HTTP_X_CLUSTER_CLIENT_IP',
     'HTTP_FORWARDED_FOR',
     'HTTP_FORWARDED',
     'HTTP_VIA',
     'REMOTE_ADDR',
    );
});

[raamdev]

Merged. Thank you!

[raamdev]

Supports a filter in case a site owner would like to revert to the old behavior.

@jaswsinc What is the old behavior?

There is also a filter that can be used to customize the lookup order

Thank you! I'll create a KB Article to document this.

[jaswrks]

@raamdev

What is the old behavior?

Old Behavior

To use $_SERVER['REMOTE_ADDR'], and only that value.

New Behavior w/ Filter to Revert

The filter I provided above will not replicate that exactly, but it is very very close.

<?php
add_filter('zencache\\share::current_ip_prioritize_remote_addr', '__return_true');

With this filter in place, if $_SERVER['REMOTE_ADDR'] is set and it's a public IP, we will use that without checking anything else; i.e., attempting to replicate the old behavior.

However, if $_SERVER['REMOTE_ADDR'] is empty, or it's not a public IP, we will still skip it and continue searching through the new list of sources. So the filter is very very close to the old behavior.

[raamdev]

@jaswsinc Perfect. Thanks for explaining that! I document that in a KB Article.

[raamdev]

Next release changelog:

• Enhancement: Improvements to IP address detection, including added support for CloudFlare IP forwarding, multiple IPs in a single header, and the ability to customize the lookup order and/or add/remove sources that are searched when looking for the current IP address. It's also possible to revert to the old IP address detection behavior (see How do I customize remote IP detection?). Issue #449

[raamdev]

@jaswsinc I wrote a KB Article to document your notes above. Thanks for explaining so clearly! :-) http://zencache.com/kb-article/how-do-i-customize-ip-address-detection/

[jaswrks]

@raamdev writes...

I wrote a KB Article to document your notes above. Thanks for explaining so clearly! :-) http://zencache.com/kb-article/how-do-i-customize-ip-address-detection/

Cool! Great :-)