implemented secure remember me functionality

composer.json

@@ -4,7 +4,8 @@
     "type": "project",
     "require": {
         "erusev/parsedown": "^1.7",
-        "vlucas/phpdotenv": "^5.6"
+        "vlucas/phpdotenv": "^5.6",
+        "phpmailer/phpmailer": "^6.9"
     },
     "authors": [
         {

functions/account_functions.php

@@ -41,7 +41,6 @@ function cookies($user, $time)
 function logout()
 {
     foreach (array_keys($_COOKIE) as $key) {
-        echo 'unsetting ' . $key . ' now.';
         setcookie($key, '', time() - 3600, '/');
         unset($_COOKIE[$key]);
     }
@@ -93,13 +92,19 @@ function login($username, $password, $stay_logged_in)
         return $error_msg;
     }
 
-    if ($stay_logged_in)
-        $time = time() + 60 * 60 * 24 * 365;
-    else
-        $time = time() + 60 * 60 * 24 * 1;
-
+    $time = time() + 60 * 60 * 1;
     cookies($user, $time);
 
+    if ($stay_logged_in) {
+        $token = bin2hex(random_bytes(64));
+        // echo $token . '<br>';
+        // echo strlen($token);
+        setcookie('remember_user', $token, time() + 60 * 60 * 24 * 30, '/', '', true, true);
+
+        $stmt = 'INSERT INTO remember_user (token, user_id, remote_addr' . (isset($_SERVER['HTTP_X_FORWARDED_FOR']) ? ', http_forward' : '') . ') VALUES ("' . $token . '", ' . $user['user_id'] . ', "' . hash('sha256', $_SERVER['REMOTE_ADDR']) . '"' . (isset($_SERVER['HTTP_X_FORWARDED_FOR']) ? ', "' . hash('sha256', $_SERVER['HTTP_X_FORWARDED_FOR']) . '"' : '') . ');';
+        exec_statement($stmt, 1);
+    }
+
     return true;
 }
 
@@ -439,7 +444,10 @@ function delete_account($user_id, $password = null, $verify_password = null)
             return $error_msg;
         }
 
-        delete_file($_ENV['PROFILE_IMAGES_FQ_PATH'] . $user['profile_picture']);
+        // Hardcoded prevention of deleting the owner's profile picture
+        if ($user['profile_picture'] != '2025.jpg')
+            delete_file($_ENV['PROFILE_IMAGES_FQ_PATH'] . $user['profile_picture']);
+
         $stmt = 'DELETE FROM user WHERE user_id = ' . $user_id . ';';
         exec_statement($stmt, 1);
         logout();
@@ -457,7 +465,10 @@ function delete_account($user_id, $password = null, $verify_password = null)
             return $error_msg;
         }
 
-        delete_file($_ENV['PROFILE_IMAGES_FQ_PATH'] . $user['profile_picture']);
+        // Hardcoded prevention of deleting the owner's profile picture
+        if ($user['profile_picture'] != '2025.jpg')
+            delete_file($_ENV['PROFILE_IMAGES_FQ_PATH'] . $user['profile_picture']);
+
         $stmt = 'DELETE FROM user WHERE user_id = ' . $user_id . ';';
         exec_statement($stmt, 1);
     }

functions/init.php

@@ -4,6 +4,7 @@ session_start();
 // Initialize Composer.
 require_once 'vendor/autoload.php';
 require_once 'db_functions.php';
+require_once 'account_functions.php';
 
 // Load environment variables.
 $dotenv = Dotenv\Dotenv::createImmutable(__DIR__ . '/../');
@@ -20,7 +21,24 @@ if ($_SESSION['initialized'] && isset($_POST['theme'])) {
     unset($_POST['theme']);
 }
 
+// Update the database and cookies to keep the user logged in.
 if (isset($_COOKIE['user_id'])) {
     exec_statement('UPDATE user SET is_active = true WHERE user_id = ' . $_COOKIE['user_id'] . ';', 1);
     exec_statement('UPDATE user SET last_active = CURRENT_TIMESTAMP WHERE user_id = ' . $_COOKIE['user_id'] . ';', 1);
+
+    $query = 'SELECT user_id, username, email, role_id, profile_picture FROM user WHERE user_id = ' . $_COOKIE['user_id'] . ';';
+    $user = query_one_result($query);
+    $time = time() + 60 * 60 * 1;
+    cookies($user, $time);
+} else if (isset($_COOKIE['remember_user'])) {
+    $query = 'SELECT * FROM remember_user WHERE token = "' . $_COOKIE['remember_user'] . '";';
+    $remember = query_one_result($query);
+    $query = 'SELECT user_id, username, email, role_id, profile_picture FROM user WHERE user_id = ' . $remember['user_id'] . ';';
+    $user = query_one_result($query);
+
+    exec_statement('UPDATE user SET is_active = true WHERE user_id = ' . $user['user_id'] . ';', 1);
+    exec_statement('UPDATE user SET last_active = CURRENT_TIMESTAMP WHERE user_id = ' . $user['user_id'] . ';', 1);
+
+    $time = time() + 60 * 60 * 1;
+    cookies($user, $time);
 }

scripts/init.sql

@@ -24,6 +24,15 @@ CREATE TABLE user (
   FOREIGN KEY (role_id) REFERENCES roles (role_id)
 );
 
+CREATE TABLE remember_user (
+  token VARCHAR(128) PRIMARY KEY,
+  user_id INT NOT NULL,
+  remote_addr VARCHAR(64) NOT NULL,
+  http_forward VARCHAR(64),
+  created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+  FOREIGN KEY (user_id) REFERENCES user (user_id)
+);
+
 CREATE TABLE article (
   article_id INT PRIMARY KEY AUTO_INCREMENT,
   author_id INT NOT NULL,

user.php

@@ -33,7 +33,7 @@ if (isset($_POST['form_id'])) {
             $msg = login(
                 $_POST['username'],
                 $_POST['password'],
-                (isset($POST['stay_logged_in']) ? true : false)
+                (isset($_POST['stay_logged_in']) ? true : false)
             );
 
             if ($msg === true)