What are the best practices for handling user authentication and sessions in PHP?

When handling user authentication and sessions in PHP, it is important to securely store user credentials, validate user input, and properly manage session data to prevent unauthorized access. One best practice is to use password hashing functions like password_hash() to securely store passwords in the database and password_verify() to validate user input. Additionally, using PHP sessions to manage user authentication and authorization can help maintain user sessions securely. 

// Start a session
session_start();

// Validate user credentials
if ($username === 'admin' && password_verify($password, $hashed_password_from_db)) {
    $_SESSION['authenticated'] = true;
} else {
    echo 'Invalid username or password';
}

// Check if user is authenticated
if (isset($_SESSION['authenticated']) && $_SESSION['authenticated'] === true) {
    // User is authenticated, perform authorized actions
} else {
    // Redirect to login page
    header('Location: login.php');
    exit;
}

Keywords

password hashing session management CSRF protection JWT authentication secure cookie handling

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