i've always used something like this for cheking cgi input. This is something that has mutated for a few years from code that my old coworker wrote: 
sub cgi_read_post

{
   local($buffer,$p,$n,$v);

   read(STDIN,$buffer,$ENV{'CONTENT_LENGTH'});
   foreach $p (split(/&/,$buffer))
   {
      ($n,$v)=split(/=/,$p);
      $v=~s/\+/ /g;
      $n=~s/\+/ /g;
      $v=~s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
      $n=~s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
      $v=~s/\cM+|\s+/ /g;
      $v=~s/^\s*|\s*$|\|//g;
      $in{$n}=($in{$n} eq ""?$v:"$in{$n}|$v");
   }
}

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BlueLines

In reply to Re: Upload Security (strip ../ by BlueLines
in thread Upload Security (strip ../, etc.) by Russ

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