I am running perl cgi scripts on Apache (1.3.33) webserver.

I have set-up individual working directories for all users in the path,say, /usr/local/wd/<unique user id>

If user 'sam' logs in and executes some programs, the logfiles are stored in the path /usr/local/wd/sam/.

I have written a perl-cgi script to view the log files using HTML::Templates.

CGI script 

# Create the HTML Page from the Templates
print $query->header();

$user = ... #get username
$log_file = .... #get logfile

my $template = "err.tmpl";

# Instantiate a new HTML::Template object
my $template = HTML::Template->new( filename => $template );

$template->param( username => $user );
$template->param( log_file => $log_file );

# Generate the HTML page
print $template->output();

[download]

Template File (err.tmpl) 


<html>
<head><title>Show Log Files</title></head>
<body >
<script>
function show_file(){ 
   window.open('/wd/<tmpl_var name = "username">/<tmpl_var name = "log
+_file">') ;
}
</script>
 
<form method="post" enctype="application/x-www-form-urlencoded" name="
+results">
<table align="center">
<tr><td><a href="javascript:show_file()">Log File</a></td></tr>
</table>
</form></body></html>

[download]

As I have set a soft link for 'wd' to '/usr/local/wd/' , I am able to open the link and view the logfile and everything seemed to be fine.

Then, I realized that by pasting the url ( say http://host.com/wd/sam/logfile1.log ) in the browser,I am able to view the logfile. Also, it opens up the possibility that I can paste http://host.com/wd/ and look at all the folders and files of all users as the webserver runs as a special user.

I am not sure how to prevent this if someone tries to access the folders in the above approach. ( I use CGI::Session to keep track of 'logged in' status of the user for all other pages but when it comes to viewing the logfiles, it goes out of control of CGI::Session )

Looking for some suggestions on how to handle this securely.

In reply to Perl CGI - Viewing logfiles - Security Issues by stumbler

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