Files
xamxam/public/media.php
Théophile Gervreau-Mercier a2b1ff5f41 security: fix all HIGH priority items from TODO.SECURITY.md
Items resolved:
- #3 (HIGH): Move file uploads outside webroot to STORAGE_ROOT (/var/www/posterg/storage).
  Uploads were previously stored in public/admin/actions/data/ which is web-accessible.
- #4 (HIGH): Align file paths and add media.php controller.
  DB paths are now storage-relative (theses/YEAR/ID/file, covers/file).
  New public/media.php serves files with path-traversal jail, MIME allow-list,
  and proper caching headers. memoire.php and search.php updated to use /media.php?path=.
  Also fixed: cover images were never recorded in thesis_files (broken INSERT).
- #5 (HIGH): RateLimit::getClientIdentifier() now uses REMOTE_ADDR only.
  HTTP_X_FORWARDED_FOR and HTTP_CLIENT_IP are attacker-controlled headers that
  allowed unlimited rate-limit bypass by rotating spoofed IPs.
- #6 (HIGH): Port public/admin/.htaccess security rules to nginx/posterg.conf.
  Apache .htaccess directives are silently ignored by nginx; none were active.
  CSP added to /admin/ location block, .log file denial added globally,
  autoindex off made explicit. Documented in nginx/HTACCESS_TO_NGINX.md.

Supporting changes:
- config/bootstrap.php: add STORAGE_ROOT constant
- nginx/SECURITY_HEADERS.md: updated to reflect admin CSP and pending public CSP
- docs/TODO.SECURITY.md: items #3-6 moved to resolved; priority order updated
2026-02-08 14:01:45 +01:00

91 lines
2.6 KiB
PHP

<?php
/**
* Media file serving controller
*
* Serves uploaded files that are stored outside the webroot (STORAGE_ROOT).
* This is the sole access point for thesis files, covers, and annexes — they
* are never exposed as direct filesystem paths from the web server.
*
* Security:
* - Strict character whitelist on the path parameter (no path traversal)
* - realpath() jail: resolved path must stay inside STORAGE_ROOT
* - MIME type verified against an allow-list before serving
*/
require_once __DIR__ . '/../config/bootstrap.php';
// --- 1. Extract and validate the requested path -------------------------------
$requestedPath = $_GET['path'] ?? '';
// Only allow safe characters: letters, digits, forward slashes, dots, hyphens, underscores.
// This explicitly rejects null bytes, backslashes, and sequences like "../".
if (!preg_match('#^[a-zA-Z0-9/_\-.]+$#', $requestedPath) || $requestedPath === '') {
http_response_code(400);
exit;
}
// --- 2. Resolve full filesystem path and enforce storage jail -----------------
$storageRoot = defined('STORAGE_ROOT') ? STORAGE_ROOT : '/var/www/posterg/storage';
$fullPath = $storageRoot . '/' . $requestedPath;
$realStorage = realpath($storageRoot);
$realFull = realpath($fullPath);
if (
$realFull === false
|| $realStorage === false
|| strpos($realFull, $realStorage . '/') !== 0
) {
http_response_code(404);
exit;
}
if (!is_file($realFull)) {
http_response_code(404);
exit;
}
// --- 3. Verify MIME type from file content (not extension) --------------------
$finfo = new finfo(FILEINFO_MIME_TYPE);
$mimeType = $finfo->file($realFull);
$allowedMimes = [
'image/jpeg',
'image/png',
'image/gif',
'application/pdf',
'video/mp4',
'application/zip',
];
if (!in_array($mimeType, $allowedMimes, true)) {
http_response_code(403);
exit;
}
// --- 4. Send response headers -------------------------------------------------
header('Content-Type: ' . $mimeType);
header('Content-Length: ' . filesize($realFull));
header('X-Content-Type-Options: nosniff');
$ext = strtolower(pathinfo($realFull, PATHINFO_EXTENSION));
if (in_array($ext, ['jpg', 'jpeg', 'png', 'gif'], true)) {
// Images: cache publicly for 7 days
header('Cache-Control: public, max-age=604800');
} elseif ($ext === 'pdf') {
// PDFs: cache for 1 day, display inline
header('Cache-Control: public, max-age=86400');
header('Content-Disposition: inline');
} else {
// Everything else: no public caching
header('Cache-Control: private, no-store');
}
// --- 5. Stream file -----------------------------------------------------------
readfile($realFull);