You are right. A more complicated scheme would be required for multiple user-id passwords. One method could be to store these user-id pairs in advance in a hash data file, say ../data/user_id, then check the incoming user-id pair against values in the existing hash. For example:

#/usr/bin/perl

use CGI qw(:standard);
use GDBM_File;

use strict;

my $q=new CGI;

#  Assume an existing saved hash %user_id with 'user' as the key and '
+id' as the value
#  created earlier by $user_id{"$user"} = $id and stored in ../data/us
+er_id

my $verify = "../data/user_id";
tie %user_id, 'GDBM_File', $verify, O_RDWR, 0666 or die "Can't tie $ve
+rify:$!";

my $user = $q->param('user');
my $id = $q->param('id');

# Check values from the query string against values in hash
unless (exists $user_id{"$user"} && $user_id{"$user"} = $id) {

     print $q->header, $q->start_html(-title=>'Page not found');
     print h2("This page was not found"), $q->end_html;

      exit;
    }
  
  untie %user_id;  
    
 # Real page code follows

[download]
By now one has other worries, like being sure the hash is locked while a tie is taking place, about how to update and delete values from the hash, about passing a name-password without security, etc.

Better advice might be to learn about SSL and OS/Web Server authentication for the particular target platform.

In reply to Re: Re: Re: Preventing changes on the by Speedy
in thread Preventing changes on the by DaWolf

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.