linumiq_net-docker/dev/supabase/migrations/0002_hardening.sql

-- 0002: pentest remediation (A4/W3 privilege reduction, A3 quota default, W1 subscription rows)
BEGIN;

-- ---------------------------------------------------------------------------
-- A4 / W3: authenticated users must NOT be able to UPDATE tunnels directly.
-- All legitimate writes (claim, token rotation, quota/usage, activation) go
-- through service-role server routes / workers. A direct grant let an owner
-- tamper with bytes_used, quota_bytes, is_active, token and subdomain.
-- ---------------------------------------------------------------------------
REVOKE UPDATE ON public.tunnels FROM authenticated;
DROP POLICY IF EXISTS tunnels_update_own ON public.tunnels;
-- SELECT (read-only dashboard) stays intact via tunnels_select_own.

-- ---------------------------------------------------------------------------
-- A3: free-tier quota default 1 TiB -> 2 GiB, and shrink existing rows that
-- still carry the old default so the kill-switch is meaningful.
-- ---------------------------------------------------------------------------
ALTER TABLE public.tunnels ALTER COLUMN quota_bytes SET DEFAULT 2147483648;
UPDATE public.tunnels
   SET quota_bytes = 2147483648
 WHERE quota_bytes = 1099511627776;

-- ---------------------------------------------------------------------------
-- W1 (enablement): ensure every user has a subscriptions row so the billing
-- webhook activation (PATCH by user) actually targets a row, and backfill
-- existing users.
-- ---------------------------------------------------------------------------
CREATE OR REPLACE FUNCTION public.handle_new_user()
RETURNS trigger
LANGUAGE plpgsql
SECURITY DEFINER
SET search_path = public
AS $$
BEGIN
  INSERT INTO public.users_profile (user_id, email)
  VALUES (NEW.id, NEW.email)
  ON CONFLICT (user_id) DO NOTHING;

  INSERT INTO public.subscriptions (user_id, plan, status)
  VALUES (NEW.id, 'free', 'active')
  ON CONFLICT (user_id) DO NOTHING;

  RETURN NEW;
END;
$$;

REVOKE ALL ON FUNCTION public.handle_new_user() FROM PUBLIC;
GRANT EXECUTE ON FUNCTION public.handle_new_user() TO supabase_auth_admin;

INSERT INTO public.subscriptions (user_id, plan, status)
SELECT id, 'free', 'active' FROM auth.users
ON CONFLICT (user_id) DO NOTHING;

COMMIT;