My dear fellow programmers

I am in need of thy help!

I have just activated the -T switch in all my scripts and everything went smoothly untill I run into the "unlink" command. He seems not to accept my untainting regexp, complaining "Insecure dependency in unlink while running with -T switch...". Here goes my code:


my $subcookie = untaint ( substr($cookie,0,6) ); # this is a substring
+ of the SID, that I use as a name for a dinamic directory for the use
+r. Also, check my untaint() function below
      
opendir (DIR, "../users/$subcookie/"); # I was using glob, but couldn´
+t make -T accept it, so I changed to readdir
         
my @files = readdir DIR;
      
foreach my $file (@files) { 
      
   my $checked_file;
      
   if ( $file =~ /(\w+)\.(\w{3,4})/ ) { $checked_file = "$1.$2"; } # a
+voiding the first "." and ".." thar readdir returns            
                 
   if ( defined $checked_file ) { unlink "../users/$subcookie/$checked
+_file"; }
               
         
}
         
close DIR;

... # and the code goes on

[download]
Here´s the untaint() function, wich is 'require'd from another .cgi: 

sub untaint {

      my $string = shift;
   
      my $clean_string;
     
      if ( $string =~ /([\w\-\_]+)/ ) { $clean_string = $1; } 
   
      else { die "ilegal character: $!"; }
   
      return $clean_string;
      
}

[download]
Anyone knows what might be? Is there a less demanding function I can use to wipe out all the files in this directory?

Thanks a lot, my friends!

André

In reply to Unlink under taint mode by Andre_br

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