How can one safely rewrite a login script with MySQL connection for a website hosted on Strato with register_globals OFF?

To safely rewrite a login script with MySQL connection for a website hosted on Strato with register_globals OFF, you should use PHP superglobals like $_POST or $_SESSION to retrieve and store user input data instead of relying on register_globals. This will help prevent security vulnerabilities such as injection attacks. 

<?php
session_start();

$servername = "localhost";
$username = "your_username";
$password = "your_password";
$dbname = "your_database";

$conn = new mysqli($servername, $username, $password, $dbname);

if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $username = $_POST["username"];
    $password = $_POST["password"];

    $sql = "SELECT * FROM users WHERE username='$username' AND password='$password'";
    $result = $conn->query($sql);

    if ($result->num_rows == 1) {
        $_SESSION["loggedin"] = true;
        header("Location: welcome.php");
    } else {
        echo "Invalid username or password";
    }
}

$conn->close();
?>

Keywords

PHP MySQL register_globals website security Strato hosting

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