Complexity of :matches ?

Michael Haardt <michael@freenet-ag.de> Mon, 11 July 2005 10:48 UTC

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To: ietf-mta-filters@imc.org
Subject: Complexity of :matches ?
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From: Michael Haardt <michael@freenet-ag.de>
Date: Mon, 11 Jul 2005 12:48:37 +0200
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Hello,

I just had a user using a wildcard pattern that took a large amount of
CPU time.  Now that this particular problem is solved, I wonder about
":matches".

Does anybody know the complexity order of recognising wildcard patterns,
which are a subset of regular expressions? Is giving users control of
patterns to be matched a security risk?

Michael