Harden WebAuthn extension origins

src/utils/origins.ts

@@ -0,0 +1,42 @@
+import type { Env } from '../types';
+
+export function normalizeOrigin(value: unknown): string | null {
+  const raw = String(value || '').trim();
+  if (!raw) return null;
+
+  try {
+    const url = new URL(raw);
+    if (!url.protocol || !url.host) return null;
+    return `${url.protocol}//${url.host}`;
+  } catch {
+    return null;
+  }
+}
+
+export function isBrowserExtensionOrigin(origin: unknown): boolean {
+  const normalized = normalizeOrigin(origin);
+  return !!normalized && (
+    normalized.startsWith('chrome-extension://')
+    || normalized.startsWith('moz-extension://')
+    || normalized.startsWith('safari-web-extension://')
+  );
+}
+
+export function getConfiguredWebAuthnAllowedOrigins(
+  env: Pick<Env, 'WEBAUTHN_ALLOWED_ORIGINS'>
+): string[] {
+  const seen = new Set<string>();
+  for (const item of String(env.WEBAUTHN_ALLOWED_ORIGINS || '').split(',')) {
+    const origin = normalizeOrigin(item);
+    if (origin) seen.add(origin);
+  }
+  return Array.from(seen);
+}
+
+export function isConfiguredWebAuthnAllowedOrigin(
+  env: Pick<Env, 'WEBAUTHN_ALLOWED_ORIGINS'>,
+  origin: unknown
+): boolean {
+  const normalized = normalizeOrigin(origin);
+  return !!normalized && getConfiguredWebAuthnAllowedOrigins(env).includes(normalized);
+}