Weird ajax remember me login bug

Question

This just came up: when I attempt to log in via ajax, for some strange reason Username field is not set is printed but the username is clearly set.

   <?php
require_once (dirname(__FILE__) . '/../../inc/inc.all.php');
$username;
$password;
$remember;
$token;

if (!isset($_POST['username'])) {
    echo "Username field must be set!";
    die();
}
$username = $_POST['username'];

if (!isset($_POST['password'])) {
    echo "Password field must be set";
    die();
}
$password = md5($_POST['password']);

$remember = $_POST['remember'];

if (!isset($_POST['token'])) {
    echo "There was a problem logging you in securly, Prehaps you are trying to log in from a different window?";
    die();
} else {
    $token = $_POST['token'];
}

// Validate token
if (!isset($token) || $token != $_SESSION['token']) {
    echo "Invalid token: There was a problem logging you in securley, Prehaps you are trying to log in from a different window?";
    die();
}

// Log the user in
$sql = "SELECT ID FROM cs_users WHERE username = '{$username}' AND password = '{$password}'";
$query = $db -> query($sql);
if ($query -> num_rows) {
    list($id) = @array_values($query -> fetch_assoc());
    if ($remember) {
        $expire = time() + 60 * 60 * 24 * 180;
        echo $id.'<br>'.$username.'<br>'.$password.'<br>';
        setcookie("id", $id, $expire);
        setcookie("username", $username, $expire);
        setcookie("password", $password, $expire);
        header("LOCATION:{$_SERVER['PHP_SELF']}");
    } else {
        $_SESSION['id'] = $id;
        $_SESSION['username'] = $username;
        $_SESSION['password'] = $password;
    }
    echo true;
} else {
    echo "Invalid username/password";
    die();
}
?>

In the above code, if I change _POST to _GET and access the page via login.php?username=mrkirby153&password=admin&remember=true&token=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx it still says that the field is unset. (Yes I know there are some major security "breaches" in my code. I am working on fixing it.)

---

var_dump($_POST) : array(0){}

Html form

<div id="login">
        <div id="login-err"></div>
        <label for="username">Username: </label>
        <input type="text" name="username" id="loginUsername" placeholder="Username">
        <label for="password">Password: </label>
        <input type="password" name="password" id="loginPass" placeholder="Password">
        <input type="button" name="loginBttn" id="loginSubmit" class="btn btn-success" value="Log in" onclick="userLogin()">
        <br>
        <label for="remember">Remember me?</label>
        <input type="checkbox" name="remember" id="loginRemember">
        <br>
        <a href="forgot">Forgot login credentials?</a>
        <input type="hidden" name="token" id="loginToken" value="<?php echo $token?>">
    </div>

Method used to ajax:

function userLogin() {

    var username = $("#loginUsername").val();
    var password = $("#loginPass").val();
    var remember = $("#loginRemember").is(':checked');
    var token = $("#loginToken").val();
    alert(username);
    $(".ajax-loader").fadeIn("slow");
    $("#login").slideUp("slow");

    $.ajax({
        type : "GET",
        url : "internal/CloudShop/ajax/login.php",
        dataType : "html",
        data : "username=" + username + "&password=" + password + "&remember=" + remember + "&token=" + token,
        success : function(result) {

            if (result != "1") {
                $("#login-err").html(result);
                $("#login").slideDown("slow");
            } else
                location.reload();
            $(".ajax-loader").fadeOut("slow");
        }
    });

}

Sitenote: It still sets the cookie though and I'm logged in if i refresh the page

Answer 1

Try changing your data parameter to:

data : { username: username,
         password: password,
         remember: remember ? 'true' : 'false',
         token: token
       },

jQuery will then encode the parameters properly.

The reason your form is being submitted twice is presumably because the normal form submission is happening after userLogin() returns. Change your submit button to:

<input type="button" name="loginBttn" id="loginSubmit" class="btn btn-success" value="Log in" onclick="userLogin(); return false;">

Returning false from the submit button disables the default action.

Answer 2

I fixed it myself. After setting the cookie, I was executing header("LOCATION:{$_SERVER['PHP_SELF']}"); which would re-call the login form again but without any $_POST data