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Dezinfekcija ulaza

Nikad ne vjerujte korisničkom unosu. Uvijek provjerite i očistite sve ulazne podatke prije upotrebe. XOOPS pruža MyTextSanitizer class za dezinfekciju unosa teksta i razne pomoćne funkcije za provjeru valjanosti.

  • Najbolje sigurnosne prakse - Opsežan sigurnosni vodič
  • CSRF-Protection - Token sustav i XoopsSecurity class
  • SQL-Injection-Prevention - Sigurnosne prakse baze podataka

Nikada ne vjerujte korisničkom unosu. Svi podaci iz vanjskih izvora moraju biti:

  1. Provjereno: Provjerite odgovara li očekivanom formatu i vrsti
  2. Dezinficirano: Uklonite ili izbjegnite potencijalno opasne likove
  3. Escaped: Prilikom ispisa, escape za određeni kontekst (HTML, JavaScript, SQL)

XOOPS pruža MyTextSanitizer class (obično poznat kao $myts) za čišćenje teksta.

// 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;

Metoda displayTarea() pruža sveobuhvatnu obradu textarea:

$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();
}

Kada koristite XMF, Zahtjev class pruža čistije rukovanje unosom:

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();
}

Za složene obrasce kreirajte namjensku provjeru class:

<?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;
}
}

Upotreba:

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

Prilikom pohranjivanja podataka u bazu podataka:

$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']]);

Različiti konteksti zahtijevaju različito bježanje:

$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');

Problem: podaci se kodiraju više puta

// 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

Problem: neki izlazi su kodirani, neki nisu

Rješenje: Uvijek koristite dosljedan pristup, po mogućnosti kodiranje na izlazu:

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

Problem: samo dezinfekcija bez provjere

Rješenje: Uvijek prvo provjerite, a zatim dezinficirajte:

// 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. Koristite MyTextSanitizer za obradu tekstualnog sadržaja
  2. Koristite filter_var() za provjeru valjanosti određenog formata
  3. Koristite pretvaranje tipa za numeričke vrijednosti
  4. Popis dopuštenih vrijednosti za odabrane unose
  5. Potvrdite prije dezinfekcije
  6. Escape na izlazu, ne na ulazu
  7. Koristite pripremljene izjave za upite baze podataka
  8. Stvorite potvrdu classes za složene obrasce
  9. Nikada ne vjerujte provjeri valjanosti na strani klijenta - uvijek provjeravajte valjanost na strani poslužitelja

#sigurnost #sanitizacija #validacija #xoops #MyTextSanitizer #input-handling