suppose you accept only ip addresses:
(changing for hostnames should be trivial..)
why not just 
unless($value =~/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/) {
       ##reject this...
}

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In reply to Re: CGI and Traceroute by cianoz
in thread CGI and Traceroute by Anonymous Monk

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