feat(auth): mandatory 2FA (TOTP + WebAuthn passkeys) with hard enrollment gate, AAL2 step-up, and single-use recovery codes

app/api/security/recovery/redeem/route.ts

@@ -0,0 +1,66 @@
+import { NextResponse, type NextRequest } from 'next/server';
+import { createSupabaseServerClient } from '@/lib/supabase/server';
+import { getSupabaseAdmin } from '@/lib/supabase/admin';
+import { jsonNoStore } from '@/lib/admin/response';
+import { hashRecoveryCode } from '@/lib/auth/recovery';
+
+export const runtime = 'nodejs';
+export const dynamic = 'force-dynamic';
+
+/**
+ * Redeem a single-use recovery code for account recovery.
+ *
+ * The user is authenticated (aal1) but locked out of step-up because they lost
+ * their authenticator/passkey. On a valid code we mark it used and DELETE all
+ * of the user's MFA factors via the admin API. GoTrue logs the user out of all
+ * sessions when a verified factor is deleted, so the client signs out and
+ * returns to /login; after signing back in (aal1, zero factors) the middleware
+ * forces fresh enrollment. We never fabricate an aal2 JWT.
+ */
+export async function POST(request: NextRequest): Promise<NextResponse> {
+  const supabase = createSupabaseServerClient();
+  const {
+    data: { user },
+  } = await supabase.auth.getUser();
+  if (!user) return jsonNoStore({ error: 'unauthorized' }, { status: 401 });
+
+  let body: { code?: string };
+  try {
+    body = (await request.json()) as { code?: string };
+  } catch {
+    return jsonNoStore({ error: 'bad_request' }, { status: 400 });
+  }
+  const code = (body.code ?? '').trim();
+  if (!code) return jsonNoStore({ error: 'invalid_code' }, { status: 400 });
+
+  const admin = getSupabaseAdmin();
+  const hash = hashRecoveryCode(code);
+
+  const { data: match, error } = await admin
+    .from('mfa_recovery_codes')
+    .select('id')
+    .eq('user_id', user.id)
+    .eq('code_hash', hash)
+    .is('used_at', null)
+    .limit(1)
+    .maybeSingle<{ id: number }>();
+  if (error) return jsonNoStore({ error: 'failed' }, { status: 500 });
+  if (!match) return jsonNoStore({ error: 'invalid_code' }, { status: 400 });
+
+  const upd = await admin
+    .from('mfa_recovery_codes')
+    .update({ used_at: new Date().toISOString() })
+    .eq('id', match.id)
+    .is('used_at', null);
+  if (upd.error) return jsonNoStore({ error: 'failed' }, { status: 500 });
+
+  // Account recovery: remove every MFA factor so the user can re-enroll.
+  const { data: list } = await admin.auth.admin.mfa.listFactors({
+    userId: user.id,
+  });
+  for (const factor of list?.factors ?? []) {
+    await admin.auth.admin.mfa.deleteFactor({ id: factor.id, userId: user.id });
+  }
+
+  return jsonNoStore({ ok: true });
+}