fix(security): tab-nabbing hardening + /acl self-lockout guard (SEC-3/4)

SEC-3: add `noopener,noreferrer` to the 5 `window.open(_blank)` sites that
don't use the returned handle (UserChips, OidcManageAccount, OtherDevices x2,
Verification), closing reverse tab-nabbing. SSOStage is intentionally excluded —
it needs the window handle + intact opener for its origin-checked SSO
postMessage handshake.

SEC-4: guard the `/acl` slash command against bricking the room.
- Extract the ACL glob helpers (isValidServerPattern/globToRegExp/matchesAnyGlob)
  from RoomServerACL into a shared utils/serverAcl.ts (+ unit test) so the
  command and the settings editor validate identically.
- Default a MISSING allow list to `*` only when the room has NO existing ACL
  (a first `/acl -d x` otherwise sent `allow: []`, which bricks the room); an
  existing ACL's absent/empty allow is preserved, not silently widened.
- Reject invalid globs; fail CLOSED on the universally-catastrophic cases
  (empty allow, or a `*` deny) even when the local domain is unknown; and reject
  any change that would ban this homeserver (self-lockout).

Guard hardened per two review passes (fail-closed on unknown domain; no silent
federation widening).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/features/room-settings/RoomServerACL.tsx

@@ -32,6 +32,7 @@ import { AsyncStatus, useAsyncCallback } from '../../hooks/useAsyncCallback';
 import { SequenceCard } from '../../components/sequence-card';
 import { SequenceCardStyle } from '../common-settings/styles.css';
 import { stopPropagation } from '../../utils/keyboard';
+import { isValidServerPattern, matchesAnyGlob } from '../../utils/serverAcl';
 import { useModalStyle } from '../../hooks/useModalStyle';
 
 // ── Types ─────────────────────────────────────────────────────────────────────
@@ -48,57 +49,6 @@ const DEFAULT_ACL: ServerAclContent = {
   allow_ip_literals: false,
 };
 
-// ── Validation ────────────────────────────────────────────────────────────────
-
-/**
- * Validate a server-name glob for an ACL entry.
- *
- * Matrix ACL `allow`/`deny` entries are globs where `*` (any run of chars) and
- * `?` (single char) may appear ANYWHERE — e.g. `*`, `*.example.com`,
- * `1.2.3.*`, `10.0.0.?`, `*.evil.*`, `*bad*`. We therefore validate the *glob*
- * rather than a concrete hostname:
- *   - reject empty / whitespace-only
- *   - allow only hostname/IP chars plus the wildcards `*` and `?`
- *     (letters, digits, dots, hyphens, colons for ports/IPv6 — NO underscore)
- *   - reject consecutive/leading/trailing dots (`...`, `.foo`, `foo.`)
- *   - reject entries with no alphanumeric or wildcard char (bare `-`, lone `:`)
- */
-function isValidServerPattern(value: string): boolean {
-  const v = value.trim();
-  if (!v) return false;
-  // Only hostname/IP glob chars — wildcards may appear at any position.
-  if (!/^[A-Za-z0-9.:*?-]+$/.test(v)) return false;
-  // Structural rules for the dotted parts.
-  if (v.startsWith('.') || v.endsWith('.') || v.includes('..')) return false;
-  // Must carry actual signal — reject pure punctuation like `-`, `:` or `-.-`.
-  if (!/[A-Za-z0-9*?]/.test(v)) return false;
-  return true;
-}
-
-/**
- * Convert an ACL glob (`*` = any run, `?` = single char) to an anchored RegExp,
- * escaping every other regex metacharacter. Used only for local self-ban
- * detection — never sent to the server.
- */
-function globToRegExp(glob: string): RegExp {
-  const escaped = glob.replace(/[.+^${}()|[\]\\]/g, '\\$&');
-  const pattern = escaped.replace(/\*/g, '.*').replace(/\?/g, '.');
-  // Case-INsensitive: Synapse's glob_to_regex uses IGNORECASE and hostnames are
-  // case-insensitive, so a deny like `MATRIX.foo.org` must still be detected as
-  // self-banning `matrix.foo.org` (otherwise the warning is a false negative).
-  return new RegExp(`^${pattern}$`, 'i');
-}
-
-function matchesAnyGlob(domain: string, globs: string[]): boolean {
-  return globs.some((glob) => {
-    try {
-      return globToRegExp(glob).test(domain);
-    } catch {
-      return false;
-    }
-  });
-}
-
 // ── Server list sub-component ─────────────────────────────────────────────────
 
 type ServerListProps = {

src/app/features/settings/account/OidcManageAccount.tsx

@@ -20,7 +20,11 @@ export function OidcManageAccount() {
   const open = useCallback(() => {
     const authUrl = authMetadata?.account_management_uri ?? authMetadata?.issuer;
     if (!authUrl) return;
-    window.open(withSearchParam(authUrl, { action: accountManagementActions.profile }), '_blank');
+    window.open(
+      withSearchParam(authUrl, { action: accountManagementActions.profile }),
+      '_blank',
+      'noopener,noreferrer',
+    );
   }, [authMetadata, accountManagementActions]);
 
   if (!authMetadata) return null;

src/app/features/settings/devices/OtherDevices.tsx

@@ -38,6 +38,7 @@ export function OtherDevices({ devices, refreshDeviceList, showVerification }: O
         action: accountManagementActions.sessionsList,
       }),
       '_blank',
+      'noopener,noreferrer',
     );
   }, [authMetadata, accountManagementActions]);
 
@@ -52,6 +53,7 @@ export function OtherDevices({ devices, refreshDeviceList, showVerification }: O
           device_id: deviceId,
         }),
         '_blank',
+        'noopener,noreferrer',
       );
     },
     [authMetadata, accountManagementActions],

src/app/features/settings/devices/Verification.tsx

@@ -278,6 +278,7 @@ export function DeviceVerificationOptions() {
           action: accountManagementActions.crossSigningReset,
         }),
         '_blank',
+        'noopener,noreferrer',
       );
       return;
     }