Code-Bin #250 - Simple PHP Login

Simple PHP Login
Posted by: Stephen | March 6, 2009 @ 11:06am

Revision 10 - Original post on March 6, 2009 @ 10:23am

PHP Code

****** RESTRICTED.PHP ****
<?php
// Use this code at the VERY TOP of all pages with restricted content
require_once("./verify.php"); // Make sure the filesystem path is correct!

// Anything below here will only be seen if user is logged in
echo "This message will only be seen by users that are successfully logged in!";
echo "<a href=\"./login.php?logout=1\">Logout</a>"; // Also, make sure this path is correct
?>

****** VERIFY.PHP ********
<?php
session_start();
if  (!($_SESSION['username'] && $_SESSION['password'])) {$logged_in = FALSE;}
elseif($_SESSION['username'] && $_SESSION['password'])  {$logged_in = TRUE;}

// Make sure the URL is correct for login.php on the next line
if($logged_in == FALSE) {die("You're not logged in. Please do so <a href=\"./login.php?uri=".urlencode($_SERVER['REQUEST_URI'])."\">here</a>.");}
?>

****** CONFIG.PHP ********
<?php
// credentials are caSe-sEnsItiVe !!!
$username = array('Admin', 'User'); // List of usernames
$password = array('adminpass', 'userpass'); // List of corresponding passwords
// Default credentials are Admin:adminpass and User:userpass
?>

****** LOGIN.PHP *********
<?php
session_start();
require_once("./config.php");

if(!($_SESSION['username'] && $_SESSION['password'])) { // They're NOT logged in
  if (! ($_REQUEST['user'] && $_REQUEST['pass'])) { // They've NOT just sent credentials to try to log in 
    echo loginForm();
  }
  else { // They've sent credentials and are trying to log in
    if(($password[array_search($_REQUEST['user'], $username)] == $_REQUEST['pass'])){ // Their credentials are verified  
      session_register("username"); $_SESSION['username'] = $_POST['user'];
      session_register("password"); $_SESSION['password'] = $_POST['pass'];
      if($_REQUEST['uri_redirect']) {header("Location: " . urldecode($_REQUEST['uri_redirect']));}
      echo "Congratulations $_SESSION[username], you have logged in!<br>\n".
      "<a href=\"?logout=1\" >Logout</a>";
    }
    else { // They've sent invalid credentials
      echo "Incorrect Password. Please <a href=\"{$_SERVER['PHP_SELF']}\">try again</a>.";    
    }
  }
}
else { // They're already logged in
  if($_REQUEST[logout]) {
    session_unregister("username");
    session_unregister("password");
    echo loginForm();
  }
  else {
  echo "You're already logged in!<BR>\n<a href=\"?logout=1\" >Logout</a>";
  }
}

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Author Comments

This is a simple login verification system built on PHP.
Note that there are four files in this post.

Instructions

Place login.php, config.php, and
verify.php all in the same folder on your server,
preferably in the root web folder.

Use restricted.php as a template for any pages
restricted to logged-in users. Make sure to change the paths in
this script if this page winds up in another folder on your server or
if you placed the 3 other files somewhere other than the root web
folder.

Enjoy!

Rating

4.53 / 8
244 Votes