RE: [PHP] User authentication
| From: | Jeff McKeon | Date: | Fri, 03 Oct 2003 18:49:30 +0000 |
| Subject: | RE: [PHP] User authentication | ||
| Groups: | php.general | ||
| Request: | Send a blank email to php-general+get-164951@lists.php.net to get a copy of this message | ||
> --- Jeff McKeon <jmckeon@telaurus.com> wrote:
> > $_SESSION['userid'] = $userid;
> > $_SESSION['userpassword'] = $userpassword;
>
> [snip]
>
> > Anything look wrong or insecure with all of this?
>
> The only thing that catches my attention is your assignments
> for $_SESSION['userid'] and $_SESSION['userpassword']. I
> assume you are performing some strict data validation on
> $userid and $userpassword before this assignment, right? If
> not, this presents a significant risk, because $_SESSION is a
> trusted array (it comes from the server, not the client).
>
> Hope that helps.
>
> Chris
Well both variables $userid and $userpassword are bounced off of a user
database table, if the username/password don't match then the session
variables are cleared with a session_destroy() call. Is that a good
enough validation?
[code begin]
session_start();
if(!isset($userid)) {
login_form();
exit;
}
else {
$_SESSION['userid'] = $userid;
$_SESSION['userpassword'] = $userpassword;
$username = auth_user($userid, $userpassword);
if(!$username) {
echo "user " . $userid . $userpassword . " Authorization
failed. " .
"You must enter a valid userid and password
combo. " .
"Click on the following link to try
again.<BR>\n";
echo "<A HREF=\"$PHP_SELF\">login</A><BR>";
echo "If you do not have login, please contact
Operations to obtain one.<br>\n";
session_destroy();
exit;
}
else echo "welcome, $username!";
echo gmmktime();
echo "<a href='./test_auth.php'>Continue</a>";
echo "<a href='./new_ticket.php'>Ticket</a>";
}
function auth_user($userid, $userpassword) {
global $default_dbname, $user_tablename;
$link_id = db_connect($default_dbname);
$query = "SELECT username FROM $user_tablename WHERE userid =
'$userid' && userpassword = password('$userpassword')";
$result = mysql_query($query);
if(!mysql_num_rows($result)) return 0;
else {
$stamp = gmmktime();
$query2 = "update $user_tablename set idle_time = $stamp
where userid = '$userid'";
$result2 = mysql_query($query2);
$query3 = "select CanEdit from $user_tablename where
userid = '$userid'";
$result3 = mysql_query($query3);
$query_data3 = mysql_fetch_row($result3);
$_SESSION['CanEdit'] = $query_data3[0];
$query_data=mysql_fetch_row($result);
return $query_data[0];
}
}
[code end]