If you use a CGI to determine $ENV{'REMOTE_HOST'} make sure you're not using a proxy cache, either by configuring your script to do so or by being routed through one transparently.

Some proxy servers send an X-Forwarded-For HTTP header, which you can retrieve using $ENV{'HTTP_X_FORWARDED_FOR'}, but the address contained within this variable may not be publicly accessible and is not guaranteed to be correct.

It might be worth checking both these values, also checking for RFC 1918 IP addresses as a failsafe mechanism.

This might be overkill, depending on your situation, but it's worth noting that the CGI approach isn't foolproof either.

Also, you can't tell if anyone else is calling your CGI - you're relying on security through obscurity to ensure nobody else accesses your script.

In reply to Re: Re: Re: Simple IP Poster by tomhukins
in thread Simple IP Poster by coolmichael

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