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Sanitasi Masukan

Jangan pernah mempercayai masukan pengguna. Selalu validasi dan sanitasi semua data masukan sebelum menggunakannya. XOOPS menyediakan kelas MyTextSanitizer untuk membersihkan input teks dan berbagai fungsi pembantu untuk validasi.

  • Keamanan-Praktik Terbaik - Panduan keamanan komprehensif
  • CSRF-Protection - Sistem token dan kelas XoopsSecurity
  • SQL-Pencegahan Injeksi - Praktik keamanan basis data

Jangan pernah mempercayai masukan pengguna. Semua data dari sumber eksternal harus:

  1. Divalidasi: Periksa apakah cocok dengan format dan jenis yang diharapkan
  2. Disanitasi: Hapus atau hindari karakter yang berpotensi berbahaya
  3. Escaped: Saat mengeluarkan, escape untuk konteks tertentu (HTML, JavaScript, SQL)

XOOPS menyediakan kelas MyTextSanitizer (biasanya disebut sebagai $myts) untuk sanitasi teks.

// Get the singleton instance
$myts = MyTextSanitizer::getInstance();
$myts = MyTextSanitizer::getInstance();
// For plain text fields (no HTML allowed)
$title = $myts->htmlSpecialChars($_POST['title']);
// This converts:
// < to &lt;
// > to &gt;
// & to &amp;
// " to &quot;
// ' to &#039;

Metode displayTarea() menyediakan pemrosesan textarea yang komprehensif:

$myts = MyTextSanitizer::getInstance();
$content = $myts->displayTarea(
$_POST['content'],
$allowhtml = 0, // 0 = No HTML allowed, 1 = HTML allowed
$allowsmiley = 1, // 1 = Smilies enabled
$allowxcode = 1, // 1 = XOOPS codes enabled (BBCode)
$allowimages = 1, // 1 = Images allowed
$allowlinebreak = 1 // 1 = Line breaks converted to <br>
);
$myts = MyTextSanitizer::getInstance();
// HTML special characters escaping
$safe_text = $myts->htmlSpecialChars($text);
// Strip slashes if magic quotes are on
$text = $myts->stripSlashesGPC($text);
// Convert XOOPS codes (BBCode) to HTML
$html = $myts->xoopsCodeDecode($text);
// Convert smileys to images
$html = $myts->smiley($text);
// Make clickable links
$html = $myts->makeClickable($text);
// Complete text processing for preview
$preview = $myts->previewTarea($text, $allowhtml, $allowsmiley, $allowxcode);
// Validate integer ID
$id = isset($_REQUEST['id']) ? (int)$_REQUEST['id'] : 0;
if ($id <= 0) {
redirect_header('index.php', 3, 'Invalid ID');
exit();
}
// Alternative with filter_var
$id = filter_var($_REQUEST['id'] ?? 0, FILTER_VALIDATE_INT);
if ($id === false || $id <= 0) {
redirect_header('index.php', 3, 'Invalid ID');
exit();
}
$email = filter_var($_POST['email'], FILTER_VALIDATE_EMAIL);
if (!$email) {
redirect_header('form.php', 3, 'Invalid email address');
exit();
}
$url = filter_var($_POST['url'], FILTER_VALIDATE_URL);
if (!$url) {
redirect_header('form.php', 3, 'Invalid URL');
exit();
}
// Additional check for allowed protocols
$parsed = parse_url($url);
$allowed_schemes = ['http', 'https'];
if (!in_array($parsed['scheme'], $allowed_schemes)) {
redirect_header('form.php', 3, 'Only HTTP and HTTPS URLs are allowed');
exit();
}
$date = $_POST['date'] ?? '';
// Validate date format (YYYY-MM-DD)
if (!preg_match('/^\d{4}-\d{2}-\d{2}$/', $date)) {
redirect_header('form.php', 3, 'Invalid date format');
exit();
}
// Validate actual date validity
$parts = explode('-', $date);
if (!checkdate($parts[1], $parts[2], $parts[0])) {
redirect_header('form.php', 3, 'Invalid date');
exit();
}
// Remove all characters except alphanumeric, underscore, and hyphen
$filename = preg_replace('/[^a-zA-Z0-9_-]/', '', $_POST['filename']);
// Or use a whitelist approach
$allowed_chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_-';
$filename = '';
foreach (str_split($_POST['filename']) as $char) {
if (strpos($allowed_chars, $char) !== false) {
$filename .= $char;
}
}
$myts = MyTextSanitizer::getInstance();
// Short text (titles, names)
$title = $myts->htmlSpecialChars(trim($_POST['title']));
// Limit length
if (strlen($title) > 255) {
$title = substr($title, 0, 255);
}
// Check for empty required fields
if (empty($title)) {
redirect_header('form.php', 3, 'Title is required');
exit();
}
// Integer
$count = (int)$_POST['count'];
$count = max(0, min($count, 1000)); // Ensure range 0-1000
// Float
$price = (float)$_POST['price'];
$price = round($price, 2); // Round to 2 decimal places
// Validate range
if ($price < 0 || $price > 99999.99) {
redirect_header('form.php', 3, 'Invalid price');
exit();
}
// Checkbox values
$is_active = isset($_POST['is_active']) ? 1 : 0;
// Or with explicit value check
$is_active = ($_POST['is_active'] ?? '') === '1' ? 1 : 0;
// Validate array input (e.g., multiple checkboxes)
$selected_ids = [];
if (isset($_POST['ids']) && is_array($_POST['ids'])) {
foreach ($_POST['ids'] as $id) {
$clean_id = (int)$id;
if ($clean_id > 0) {
$selected_ids[] = $clean_id;
}
}
}
// Validate against allowed values
$allowed_statuses = ['draft', 'published', 'archived'];
$status = $_POST['status'] ?? '';
if (!in_array($status, $allowed_statuses)) {
redirect_header('form.php', 3, 'Invalid status');
exit();
}

Saat menggunakan XMF, kelas Permintaan menyediakan penanganan input yang lebih bersih:

use Xmf\Request;
// Get integer
$id = Request::getInt('id', 0);
// Get string
$title = Request::getString('title', '');
// Get array
$ids = Request::getArray('ids', []);
// Get with method specification
$id = Request::getInt('id', 0, 'POST');
$search = Request::getString('q', '', 'GET');
// Check request method
if (Request::getMethod() !== 'POST') {
redirect_header('form.php', 3, 'Invalid request method');
exit();
}

Untuk formulir yang kompleks, buat kelas validasi khusus:

<?php
namespace XoopsModules\MyModule;
class Validator
{
private $errors = [];
public function validateItem(array $data): bool
{
$this->errors = [];
// Title validation
if (empty($data['title'])) {
$this->errors['title'] = 'Title is required';
} elseif (strlen($data['title']) > 255) {
$this->errors['title'] = 'Title must be 255 characters or less';
}
// Email validation
if (!empty($data['email'])) {
if (!filter_var($data['email'], FILTER_VALIDATE_EMAIL)) {
$this->errors['email'] = 'Invalid email format';
}
}
// Status validation
$allowed = ['draft', 'published'];
if (!in_array($data['status'], $allowed)) {
$this->errors['status'] = 'Invalid status';
}
return empty($this->errors);
}
public function getErrors(): array
{
return $this->errors;
}
public function getError(string $field): ?string
{
return $this->errors[$field] ?? null;
}
}

Penggunaan:

$validator = new Validator();
$data = [
'title' => $_POST['title'],
'email' => $_POST['email'],
'status' => $_POST['status'],
];
if (!$validator->validateItem($data)) {
$errors = $validator->getErrors();
// Display errors to user
}

Saat menyimpan data dalam database:

$myts = MyTextSanitizer::getInstance();
// For storage (will be processed again on display)
$title = $myts->addSlashes($_POST['title']);
// Better: Use prepared statements (see SQL Injection Prevention)
$sql = "INSERT INTO " . $xoopsDB->prefix('mytable') . " (title) VALUES (?)";
$result = $xoopsDB->query($sql, [$_POST['title']]);

Konteks yang berbeda memerlukan pelolosan yang berbeda:

$myts = MyTextSanitizer::getInstance();
// HTML context
echo $myts->htmlSpecialChars($title);
// Within HTML attributes
echo htmlspecialchars($title, ENT_QUOTES, 'UTF-8');
// JavaScript context
echo json_encode($title);
// URL parameter
echo urlencode($title);
// Full URL
echo htmlspecialchars($url, ENT_QUOTES, 'UTF-8');

Masalah: Data dikodekan beberapa kali

// Wrong - double encoding
$title = $myts->htmlSpecialChars($myts->htmlSpecialChars($_POST['title']));
// Right - encode once, at the appropriate time
$title = $_POST['title']; // Store raw
echo $myts->htmlSpecialChars($title); // Encode on output

Masalah: Beberapa output dikodekan, beberapa tidak

Solusi: Selalu gunakan pendekatan yang konsisten, sebaiknya pengkodean pada keluaran:

// Template assignment
$GLOBALS['xoopsTpl']->assign('title', htmlspecialchars($title, ENT_QUOTES, 'UTF-8'));

Masalah: Hanya melakukan sanitasi tanpa memvalidasi

Solusi: Selalu validasi terlebih dahulu, lalu sanitasi:

// First validate
if (!preg_match('/^[a-z0-9_]+$/', $_POST['username'])) {
redirect_header('form.php', 3, 'Username contains invalid characters');
exit();
}
// Then sanitize for storage/display
$username = $myts->htmlSpecialChars($_POST['username']);
  1. Gunakan MyTextSanitizer untuk pemrosesan konten teks
  2. Gunakan filter_var() untuk validasi format tertentu
  3. Gunakan casting tipe untuk nilai numerik
  4. Masukkan nilai yang diizinkan untuk input tertentu
  5. Validasi sebelum melakukan sanitasi
  6. Escape pada keluaran, bukan pada masukan
  7. Gunakan pernyataan yang telah disiapkan untuk kueri database
  8. Buat kelas validasi untuk formulir kompleks
  9. Jangan pernah mempercayai validasi sisi klien - selalu validasi sisi server

#keamanan #sanitasi #validasi #xoops #MyTextSanitizer #penanganan input