Re: [squid-users] bad regex is blocking the wrong sites

On Mon, 3 Oct 2011, devadmin wrote:

> heres the contents of the bad regex blacklist im using, just a single
> line.
>
> .*porn*.*
>
> one entry. and this single entry causes all those sites/services and
> more to be blocked. What am I doing wrong?

The key is: regex != fileglob.

In regular expressions, "*" means "the preceding atom repeated zero or
more times", _not_ "a string of any characters". Also, "." is an atom that
matches any single character (if it's used outside square brackets).

So, ".*porn*.*" means:

Zero or more of anything, followed by "por", followed by zero or more "n",
followed by zero or more of anything.

If you're trying to match dot-anything-porn-anything-dot, try this:

   \.[^.]*porn[^.]*\.

which means:

A period, followed by zero or more not-periods, followed by "porn",
followed by zero or more not-periods, followed by a period.

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