If and else statement , test on the user account status - php

Question

I want to make test on the status of the user account.
If the account is active I redirect him to the user page
If the account is not active I redirect him to login page again with an error
Here’s my code
<?php
require('conexion.php');
$username = '';
$password = '';
if (isset($_POST['username']) || !empty($_POST['username']))
$username = $_POST['username'];
if (isset($_POST['password']) || !empty($_POST['password']))
$password = $_POST['password'];
$q1 = "select * from user where username='" . $username . "' and password='" . $password . "' ";
$r1 = $db->query($q1);
$i = 0;
echo $q1;
while ($d1 = $r1->fetch()) {
$i++;
//$id_perso = $d1['id_perso'];
$type = $d1['type'];
$nom = $d1['nom'];
$prenom = $d1['prenom'];
$statut = $d1['statut'];
$user_id = $d1['id_user'];
}
if ($i == 1) { // START IF
session_start ();
$_SESSION['username'] = $_POST['username'];
$_SESSION['password'] = $_POST['password'];
$_SESSION['type'] = $type;
$_SESSION['nom'] = $nom;
$_SESSION['prenom'] = $prenom;
$_SESSION['statut'] = $statut;
$_SESSION['user_id'] = $user_id;
if ($statut = 'actif') {
if ($_SESSION['type'] == 'admin') {
$path = "admin/index.php";
}
if ($_SESSION['type'] == 'professeur') {
$path = "professeur/index.php";
}
if ($_SESSION['type'] == 'doctorant') {
$path = "doctorant/index.php";
}
header("Location:".$path);
} elseif ($statut = 'inactif') {
header("location:login.php?inactif");
}
} else {
header("location:login.php?error=1");
}
?>

Answer 1

Why don't you use a boolean, should be easier.
/*
1. Get Status from Database
2. When the user is active, you set the boolean true, else false. */
$booleanVar = false;
if($booleanVar) {
// user is active
} else {
// user is inactive
}
EDIT:
Redirecting with header works like this, I believe its Case Insensitive:
header('Location: somesite.php?abc');
Also you have to check values with "==" (for equal) or "===" (for identical)

Answer 2

You could simply get the same result if you do this with a simple query:
You check if the password and the username matches AND check if the account has been activated.
$sql = 'SELECT `id` FROM `user` WHERE `username` = '$username' AND `password` = '$password' AND `statut` = 1'
You then can run the query and check if number of rows is greater than 0.
$sql = $db->query($sql);
$results = $sql->fetch();
if (count($results) > 0) {
// Account is activated
} else {
header("location: login.php");
exit;
}
You are also vulnerable to SQL-injections by inserting your variables directly into your query, wich Edhurtig noticed! The best way to prevend SQL-injections is to use PDO prepared statements.

Answer 3

First and foremost: DO NOT STORE PASSWORDS IN PLAINTEXT. Do some research into secure hashing algorithms (not md5) or use a third party authentication service like Google, Facebook, Github, ect.
Second: This code is vulnerable to SQL injection via $_POST['username'] and $_POST['password']
Also it was a bit unclear what was being asked but I felt it was important to point out the aforementioned issues because they are so security critical.
Here is what I was able to cleanup. I would strongly recommend using a third party authentication service though
<?php
require('conexion.php');
$salt = "random_string";
$username='';
$password='';
if (isset($_POST['username'])||!empty($_POST['username'])) $username = $_POST['username'];
if (isset($_POST['password'])||!empty($_POST['password'])) $password = $_POST['password'];
$hashed_password = some_hashing_function_1000_times($password, $salt);
$q1="SELECT * FROM user WHERE `user`.`username` = '%s' AND `user`.`password` = '%s' LIMIT 1";
// I hope that $db has a prepare function, it prevents SQL injections from $_POST['username'] and $_POST['password']
$sql = $db->prepare($q1, $username, $hashed_password);
$r1= $db->query($q1);
$user = $r1->fetch();
if( $user ) { // START IF
session_start();
$_SESSION['username'] = $_POST['username'];
$_SESSION['password'] = $_POST['password'];
$_SESSION['type'] = $type;
$_SESSION['nom'] = $nom;
$_SESSION['prenom'] = $prenom;
$_SESSION['statut'] = $statut;
$_SESSION['user_id'] = $user_id;
if($statut == 'actif'){
if($_SESSION['type']=='admin') { $path="admin/index.php"; }
if($_SESSION['type']=='professeur'){ $path="professeur/index.php"; }
if($_SESSION['type']=='doctorant') { $path="doctorant/index.php"; }
header("Location: " . $path);
exit();
}
else if ($statut == 'inactif') {
header("Location: login.php?inactif");
exit();
}
}
header("Location: login.php?error=1");
exit();
// No Closing PHP tag at end of file