php上传文件 漏洞

<?php
if ($_FILES['file']['error'] == UPLOAD_ERR_OK) {
    $fileTmpPath = $_FILES['file']['tmp_name'];
    $fileName = $_FILES['file']['name'];
    $fileSize = $_FILES['file']['size'];
    $fileType = $_FILES['file']['type'];

    // 检查文件扩展名
    $allowedExtensions = ['jpg', 'jpeg', 'png', 'gif'];
    $fileExtension = pathinfo($fileName, PATHINFO_EXTENSION);
    if (!in_array($fileExtension, $allowedExtensions)) {
        die("Invalid file extension.");
    }

    // 检查文件MIME类型
    $allowedMimeTypes = ['image/jpeg', 'image/png', 'image/gif'];
    if (!in_array($fileType, $allowedMimeTypes)) {
        die("Invalid file type.");
    }

    // 检查文件内容（以图片为例）
    $image = @getimagesize($fileTmpPath);
    if (!$image) {
        die("Invalid image file.");
    }

    // 存储文件
    $uploadPath = 'uploads/' . $fileName;
    if (move_uploaded_file($fileTmpPath, $uploadPath)) {
        echo "File uploaded successfully.";
    } else {
        echo "Failed to upload file.";
    }
} else {
    echo "Error uploading file.";
}
?>