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

config/bootstrap.php

@@ -6,6 +6,11 @@
 // Define application root
 define('APP_ROOT', dirname(__DIR__));
 
+// Storage directory for uploaded files — intentionally outside the webroot
+// so no uploaded content is ever directly web-accessible (items #3 & #4).
+// Files are served through public/media.php which validates paths and MIME types.
+define('STORAGE_ROOT', '/var/www/posterg/storage');
+
 // Error reporting
 if (php_sapi_name() === 'cli-server') {
     // Development mode

docs/TODO.SECURITY.md

@@ -12,6 +12,10 @@
 | # | Issue | Severity | Resolution |
 |---|-------|----------|------------|
 | 1 | No HTTPS — admin credentials exposed in transit | 🔴 CRITICAL | **TLS is terminated upstream by the reverse proxy** (outside nginx). nginx.conf does not need to handle TLS directly. |
+| 3 | Uploaded files stored inside the webroot | 🟠 HIGH | Storage moved to `STORAGE_ROOT` (`/var/www/posterg/storage/`), defined in `config/bootstrap.php`. `formulaire.php` updated. |
+| 4 | File path mismatch — media files broken and insecure | 🟠 HIGH | DB paths are now storage-relative (`theses/YEAR/ID/file`, `covers/file`). New controller `public/media.php` serves files safely. `memoire.php` and `search.php` updated to use `/media.php?path=…`. Cover recording in `formulaire.php` fixed (was never inserted into DB). |
+| 5 | Rate limiter bypassed by IP spoofing (`X-Forwarded-For`) | 🟠 HIGH | `lib/RateLimit.php` `getClientIdentifier()` now uses `REMOTE_ADDR` only. |
+| 6 | `.htaccess` security rules silently ignored by nginx | 🟠 HIGH | All rules ported to `nginx/posterg.conf` (CSP to `/admin/` block, `.log` denial, `autoindex off`). See `nginx/HTACCESS_TO_NGINX.md`. |
 | 13 | Deprecated `X-XSS-Protection` header | 🔵 LOW | **Removed** from `nginx/posterg.conf`; see `nginx/SECURITY_HEADERS.md` for rationale. |
 
 ---
@@ -57,9 +61,7 @@
 
 | # | Issue | Severity | Files |
 |---|-------|----------|-------|
-| 6 | `.htaccess` security rules silently ignored by nginx | 🟠 HIGH | `public/admin/.htaccess` → move all headers/rules into nginx server block |
+| 11 | Missing Content-Security-Policy on public pages | 🟡 MEDIUM | `nginx/posterg.conf` → add `Content-Security-Policy` header to main server block (admin already has CSP via item #6) |
-| 11 | Missing Content-Security-Policy on public pages | 🟡 MEDIUM | `nginx/posterg.conf` → add `Content-Security-Policy` header |
-| 13 | Deprecated `X-XSS-Protection` header | 🔵 LOW | ✅ `nginx/posterg.conf` — header removed; documented in `nginx/SECURITY_HEADERS.md` |
 
 ---
 
@@ -72,40 +74,27 @@
 
 ---
 
-### File Upload / Storage
+### Admin Panel — Error Logging
 
 | # | Issue | Severity | Files |
 |---|-------|----------|-------|
-| 3 | Uploaded files stored inside the webroot | 🟠 HIGH | `public/admin/actions/formulaire.php` → move uploads to `/var/www/posterg/storage/` |
-| 4 | File path mismatch — media files broken and insecure | 🟠 HIGH | `formulaire.php`, `memoire.php`, `search.php` → align stored paths with a controller-served endpoint |
 | 9 | `error.log` written to a web-accessible path | 🟡 MEDIUM | `public/admin/actions/formulaire.php` → use absolute path outside webroot |
 
 ---
 
-### Rate Limiting
-
-| # | Issue | Severity | Files |
-|---|-------|----------|-------|
-| 5 | Rate limiter bypassed by IP spoofing (`X-Forwarded-For`) | 🟠 HIGH | `lib/RateLimit.php` → use `REMOTE_ADDR` only |
-
----
-
 ### File Import
 
 | # | Issue | Severity | Files |
 |---|-------|----------|-------|
 | 12 | CSV import missing server-side MIME validation | 🟡 MEDIUM | `public/admin/import.php` → add `finfo` MIME check |
 
-
-
 ---
 
 ## Priority Order for Remaining Work
 
 1. 🔴 **CRITICAL** — Item 2 (add simple PHP session auth guard)
-2. 🟠 **HIGH** — Items 3, 4, 5, 6 (file storage overhaul + nginx hardening + rate-limiter fix)
+2. 🟡 **MEDIUM** — Items 7, 8, 9, 11, 12 (sanitisation standardisation, session hardening, CSP, error log, CSV MIME)
-3. 🟡 **MEDIUM** — Items 7, 8, 9, 11, 12 (sanitisation standardisation, session hardening, CSP, error log, CSV MIME)
+3. 🔵 **LOW** — ✅ All done (items 13–16)
-4. 🔵 **LOW** — ✅ All done (items 13–16)
 
 ---
 

lib/RateLimit.php

@@ -30,17 +30,15 @@ class RateLimit {
      * Get client identifier (IP address)
      * @return string Client identifier
      */
-    private function getClientIdentifier() {
+    private function getClientIdentifier(): string {
-        // Try to get real IP if behind proxy
+        // Use REMOTE_ADDR only — HTTP_X_FORWARDED_FOR and HTTP_CLIENT_IP
-        if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
+        // are fully attacker-controlled request headers and must never be
-            $ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
+        // trusted for rate-limiting purposes (an attacker can rotate them
-        } elseif (!empty($_SERVER['HTTP_CLIENT_IP'])) {
+        // freely to bypass the limiter). Nginx-level rate limiting also
-            $ip = $_SERVER['HTTP_CLIENT_IP'];
+        // uses $binary_remote_addr for the same reason. If this app is
-        } else {
+        // ever placed behind a trusted reverse-proxy, IP extraction should
-            $ip = $_SERVER['REMOTE_ADDR'] ?? 'unknown';
+        // be handled at the nginx level, not here.
-        }
+        return $_SERVER['REMOTE_ADDR'] ?? 'unknown';
-
-        return $ip;
     }
 
     /**

nginx/HTACCESS_TO_NGINX.md

@@ -0,0 +1,36 @@
+# `.htaccess` → nginx migration (item #6)
+
+> **Problem:** `public/admin/.htaccess` contained Apache-specific security
+> directives that nginx **silently ignores**. None of the rules were active
+> in production.
+
+---
+
+## Rules migrated into `nginx/posterg.conf`
+
+| Apache `.htaccess` rule | nginx equivalent | Location |
+|---|---|---|
+| `Header always set X-Frame-Options "SAMEORIGIN"` | `add_header X-Frame-Options "SAMEORIGIN" always;` | main `server` block (already present) |
+| `Header always set X-Content-Type-Options "nosniff"` | `add_header X-Content-Type-Options "nosniff" always;` | main `server` block (already present) |
+| `Header always set X-XSS-Protection "1; mode=block"` | **Intentionally omitted** — deprecated & counterproductive; see `SECURITY_HEADERS.md` | — |
+| `Header always set Referrer-Policy "strict-origin-when-cross-origin"` | `add_header Referrer-Policy "strict-origin-when-cross-origin" always;` | main `server` block (already present) |
+| `Header always set Content-Security-Policy "..."` | `add_header Content-Security-Policy "..." always;` | `/admin/` location block (**added**) |
+| `Options -Indexes` | `autoindex off;` | `/admin/` location block (**added**; nginx default is off, explicit for clarity) |
+| `<FilesMatch "^\."> Require all denied` | `location ~ /\.(?!well-known).*` deny | main `server` block (already present) |
+| `<FilesMatch "(composer\.(json\|lock)\|error\.log)$"> Require all denied` | `location ~* \.(md\|txt\|sql\|sh\|json\|gitignore)$` deny + `location ~* \.log$` deny | main `server` block (`log` rule **added**) |
+| `php_flag display_errors Off` | Handled by `config/bootstrap.php` (`ini_set('display_errors', '0')`) | PHP |
+| `php_flag log_errors On` | Handled by `config/bootstrap.php` (`ini_set('log_errors', '1')`) | PHP |
+| `php_value error_log error.log` | Handled by `config/bootstrap.php`; should use absolute path (item #9) | PHP |
+
+---
+
+## Status of `public/admin/.htaccess`
+
+The file is now **dead code** on this nginx server. It has been left in place
+(harmless) so it would still work if the project were ever tested behind Apache
+(e.g., `php -S` built-in server doesn't read it either). All security rules it
+previously attempted to set are now enforced by nginx directly.
+
+---
+
+*Added: 2026-02-08 — security item #6*

nginx/SECURITY_HEADERS.md

@@ -1,6 +1,6 @@
 # Security Headers — nginx/posterg.conf
 
-## Headers in use
+## Headers in use (main server block — all pages)
 
 | Header | Value | Purpose |
 |--------|-------|---------|
@@ -9,6 +9,17 @@
 | `Referrer-Policy` | `strict-origin-when-cross-origin` | Limit referrer leakage |
 | `Permissions-Policy` | `geolocation=(), microphone=(), camera=()` | Disable unused browser APIs |
 
+## Headers in use (`/admin/` location block)
+
+| Header | Value | Purpose |
+|--------|-------|---------|
+| `Content-Security-Policy` | `default-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; object-src 'none'; frame-ancestors 'none';` | Restrict resource origins; block embedding |
+| `X-Robots-Tag` | `noindex, nofollow` | Prevent search-engine indexing of admin |
+
+These were previously declared in `public/admin/.htaccess` as Apache
+`mod_headers` directives, which nginx silently ignores. They are now
+enforced directly; see `HTACCESS_TO_NGINX.md` for the full migration log.
+
 ## Intentionally omitted headers
 
 ### `X-XSS-Protection`
@@ -21,10 +32,11 @@ This header was **removed** (was `"1; mode=block"`).
 to expose response bodies that would otherwise be blocked. Sending it provides
 no protection and may introduce risk.
 
-**Correct mitigation:** a proper `Content-Security-Policy` header (todo item #11).
+**Correct mitigation:** a proper `Content-Security-Policy` header (now done for
+`/admin/`; public-page CSP is todo item #11).
 
 ## Pending headers
 
-| Header | Status |
+| Header | Scope | Status |
-|--------|--------|
+|--------|-------|--------|
-| `Content-Security-Policy` | ⏳ todo item #11 |
+| `Content-Security-Policy` | Public pages (non-admin) | ⏳ todo item #11 |

nginx/posterg.conf

@@ -74,6 +74,13 @@ server {
         # Rate limiting for admin
         limit_req zone=admin burst=5 nodelay;
 
+        # Content-Security-Policy — ported from public/admin/.htaccess which nginx ignores (item #6).
+        # Tighter policy for admin: no external sources, no object embedding.
+        add_header Content-Security-Policy "default-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; object-src 'none'; frame-ancestors 'none';" always;
+
+        # Disable directory listing (nginx default is off; explicit for defence-in-depth, item #6)
+        autoindex off;
+
         # Allow access to public assets without authentication
         location ~ ^/admin/(css|js|images)/ {
             auth_basic off;
@@ -134,6 +141,14 @@ server {
         try_files $uri $uri/ =404;
     }
 
+    # Deny access to log files — public/admin/.htaccess had this rule but Apache
+    # .htaccess directives are silently ignored by nginx (item #6).
+    location ~* \.log$ {
+        deny all;
+        access_log off;
+        log_not_found off;
+    }
+
     # Deny access to .htaccess files (if Apache's document root concurs with nginx's)
     location ~ /\.ht {
         deny all;

public/admin/actions/formulaire.php

@@ -194,9 +194,10 @@ try {
 
     // ===== HANDLE FILE UPLOADS =====
 
-    // Create necessary directories
+    // Create necessary directories — outside the webroot (security items #3 & #4).
-    $uploadBaseDir = __DIR__ . "/data/theses/{$annee}/{$identifier}/";
+    // Files are served through /media.php, never directly via a URL path.
-    $coverDir = __DIR__ . "/data/covers/";
+    $uploadBaseDir = STORAGE_ROOT . "/theses/{$annee}/{$identifier}/";
+    $coverDir = STORAGE_ROOT . "/covers/";
 
     if (!file_exists($uploadBaseDir)) {
         mkdir($uploadBaseDir, 0755, true);
@@ -228,11 +229,18 @@ try {
 
             if (move_uploaded_file($couverture["tmp_name"], $targetFile)) {
                 chmod($targetFile, 0644);
-                $coverPath = "data/covers/" . $safeFileName;
+                // Path stored relative to STORAGE_ROOT; served via /media.php?path=...
+                $coverPath = "covers/" . $safeFileName;
 
-                // Update thesis record with cover path
+                // Record cover in thesis_files (type = 'cover')
-                $stmt = $pdo->prepare("UPDATE theses SET identifier = ? WHERE id = ?");
+                $db->insertThesisFile(
-                // Store cover path in remarks for now (we could add a cover_path column)
+                    $thesisId,
+                    'cover',
+                    $coverPath,
+                    basename($couverture["name"]),
+                    $couverture["size"],
+                    $mimeType
+                );
                 error_log("Cover image uploaded: " . $safeFileName);
             }
         } else {
@@ -284,11 +292,11 @@ try {
                     $fileType = 'main';
                 }
 
-                // Insert file record
+                // Insert file record — path relative to STORAGE_ROOT
                 $db->insertThesisFile(
                     $thesisId,
                     $fileType,
-                    "data/theses/{$annee}/{$identifier}/" . $safeFileName,
+                    "theses/{$annee}/{$identifier}/" . $safeFileName,
                     basename($files["name"][$i]),
                     $files["size"][$i],
                     $mimeType

public/media.php

@@ -0,0 +1,90 @@
+<?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);

public/memoire.php

@@ -125,16 +125,16 @@ include APP_ROOT . '/includes/header.php'; ?>
                     <div class="block">
                         <?php if ($ext === 'pdf'): ?>
                             <!-- Display PDF files using the embed element -->
-                            <embed src="<?= htmlspecialchars($file['file_path']); ?>" type="application/pdf" width="100%" height="600px" />
+                            <embed src="/media.php?path=<?= urlencode($file['file_path']); ?>" type="application/pdf" width="100%" height="600px" />
                         <?php elseif (in_array($ext, ['jpg', 'jpeg', 'png', 'gif', 'bmp'])): ?>
                             <!-- Display image files using the img element -->
                             <figure>
-                                <img src="<?= htmlspecialchars($file['file_path']); ?>" alt="<?= htmlspecialchars($file['file_name']); ?>">
+                                <img src="/media.php?path=<?= urlencode($file['file_path']); ?>" alt="<?= htmlspecialchars($file['file_name']); ?>">
                             </figure>
                         <?php elseif ($ext === 'mp4'): ?>
                             <!-- Display MP4 video files using the video element -->
                             <video width="100%" height="auto" controls>
-                                <source src="<?= htmlspecialchars($file['file_path']); ?>" type="video/mp4">
+                                <source src="/media.php?path=<?= urlencode($file['file_path']); ?>" type="video/mp4">
                                 Your browser does not support the video tag.
                             </video>
                         <?php endif; ?>

public/search.php

@@ -341,9 +341,9 @@ include APP_ROOT . '/includes/header.php'; ?>
                   if (!empty($item['id'])) {
                     $files = $db->getThesisFiles($item['id']);
                     foreach ($files as $file) {
-                      $ext = strtolower(pathinfo($file['file_path'], PATHINFO_EXTENSION));
+                      // Look for dedicated cover file (type = 'cover')
-                      if (in_array($ext, ['jpg', 'jpeg', 'png', 'gif']) && $file['file_type'] === 'main') {
+                      if ($file['file_type'] === 'cover') {
-                        $coverImage = $file['file_path'];
+                        $coverImage = '/media.php?path=' . urlencode($file['file_path']);
                         break;
                       }
                     }