I took a look at my logs and found out that earlier this year, random computers made a request to resources and my log recorded it as follows:
"GET http://testp3.pospr.waw.pl/testproxy.php HTTP/1.1"
I also received a few others that are similar except that testp3 is testp1 and testp4 instead. So I checked the URL and it returned my IP address.
I'm tempted to make a module that stops requests starting with http:// from accessing any part of my server (even before mod-rewrite kicks in) because I like my server fast.
Because my server is shared amongst a large number of clients, I need to know the following before I feel I can establish a solid answer to my question:
Are there cases where merging a URL within a URL is actually necessary? I don't want to block the inner http:// only to have a valid client complain that his system doesn't work.
Do requests like this on an apache server actually cause the server to connect to the inner URL requested (such as: http://testp3.pospr.waw.pl/testproxy.php)? If so, then I feel blocking will gain me both speed and lower bandwidth costs.
So block, or no block, and why?
P.S. I'm not asking this to gather opinions, I'm asking for a good answer to help me save bandwidth, improve speed and maintain client satisfaction.