security: v2.0 — AES-GCM crypto, SSRF guards, rate limits, hardening

Breaking wire-format change: dual-read (V1+V2) / single-write (V2) so
existing user secrets, stored messages, and inter-tenant key keep
working. Old clients and relays lose cross-version chat until both
sides are upgraded.

Relay
- Switch clientEncrypt/masterEncrypt to AES-256-GCM with HKDF-derived
  per-ciphertext salts; keep CBC-V1 fallback on decrypt only.
- On-bootstrap migration re-envelopes tenant secret_encrypted and the
  inter-tenant key to GCM-V2 (idempotent).
- CORS: stop reflecting arbitrary Origin; allow own origin + optional
  RELAY_CORS_ORIGINS env allowlist; drop Access-Control-Allow-Credentials.
- Generic error messages replace "no such user: <name>" enumeration.
- Exception messages no longer echoed back; logged server-side.
- Collab-lock max hold capped at 10min so a member can't grief-refresh
  forever.
- Attachment filenames validated against hex.<ext> pattern.
- Passwords min length 10; /api/account/password rate-limited.

App / Electron client
- Shared hyprcrdRelayEncrypt/Decrypt helpers (GCM-V2 write, V1 read).
- Chat + collab-buckets plugins delegate to the shared helpers.
- Poll + push + attachments migrated to the dual-format path.
- /api/relay/settings GET returns has_key boolean; secret never echoed.
- Setup endpoint now CSRF-checked.
- SSRF: CURLOPT_PROTOCOLS restricted to HTTP(S) everywhere; bookmarks
  favicon fetch also blocks private/loopback/link-local.
- Login / password-change rate limiter moved to DB-backed IP keying.
- Passwords min length 10 throughout.
- Zip import enforces per-file (25MB) and total (500MB) caps, extension
  allowlist, no-overwrite.
- Verbose relay-push debug gated behind APP_DEBUG env.

Version bumped to 2.0.0 (protocol-breaking).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

public/plugins/bookmarks/backend.php

@@ -20,6 +20,17 @@ PluginManager::instance()->onApiRoute(function (string $route, string $method) {
         echo json_encode(['error' => 'valid url required']);
         exit;
     }
+    $scheme = strtolower((string)parse_url($url, PHP_URL_SCHEME));
+    if ($scheme !== 'http' && $scheme !== 'https') {
+        http_response_code(400);
+        echo json_encode(['error' => 'only http/https URLs allowed']);
+        exit;
+    }
+    if (!hyprcrdUrlHostIsPublic($url)) {
+        http_response_code(400);
+        echo json_encode(['error' => 'URL host is not publicly reachable']);
+        exit;
+    }
 
     $ch = curl_init($url);
     curl_setopt_array($ch, [
@@ -30,6 +41,7 @@ PluginManager::instance()->onApiRoute(function (string $route, string $method) {
         CURLOPT_USERAGENT      => 'Mozilla/5.0 (compatible; hyprcrd-bookmarks/1.0)',
         CURLOPT_SSL_VERIFYPEER => true,
     ]);
+    hyprcrdApplySafeCurlOpts($ch);
     $html = curl_exec($ch);
     $status = curl_getinfo($ch, CURLINFO_HTTP_CODE);
     $finalUrl = curl_getinfo($ch, CURLINFO_EFFECTIVE_URL) ?: $url;
@@ -63,18 +75,21 @@ PluginManager::instance()->onApiRoute(function (string $route, string $method) {
     }
 
     $faviconData = '';
-    $ch2 = curl_init($faviconUrl);
-    curl_setopt_array($ch2, [
+    $faviconScheme = strtolower((string)parse_url($faviconUrl, PHP_URL_SCHEME));
+    $favCh = ($faviconScheme === 'http' || $faviconScheme === 'https') && hyprcrdUrlHostIsPublic($faviconUrl);
+    $ch2 = $favCh ? curl_init($faviconUrl) : null;
+    if ($ch2) curl_setopt_array($ch2, [
         CURLOPT_RETURNTRANSFER => true,
         CURLOPT_FOLLOWLOCATION => true,
         CURLOPT_MAXREDIRS      => 3,
         CURLOPT_TIMEOUT        => 5,
         CURLOPT_USERAGENT      => 'Mozilla/5.0 (compatible; hyprcrd-bookmarks/1.0)',
     ]);
-    $favBytes = curl_exec($ch2);
-    $favStatus = curl_getinfo($ch2, CURLINFO_HTTP_CODE);
-    $favMime = curl_getinfo($ch2, CURLINFO_CONTENT_TYPE) ?: 'image/x-icon';
-    curl_close($ch2);
+    if ($ch2) hyprcrdApplySafeCurlOpts($ch2);
+    $favBytes = $ch2 ? curl_exec($ch2) : false;
+    $favStatus = $ch2 ? curl_getinfo($ch2, CURLINFO_HTTP_CODE) : 0;
+    $favMime = $ch2 ? (curl_getinfo($ch2, CURLINFO_CONTENT_TYPE) ?: 'image/x-icon') : 'image/x-icon';
+    if ($ch2) curl_close($ch2);
 
     if ($favBytes && $favStatus >= 200 && $favStatus < 400 && strlen($favBytes) <= 32768) {
         $mime = preg_replace('/;.*$/', '', $favMime);