Build MVP with Pi installer and atomic updates

server/src/security.ts

@@ -0,0 +1,23 @@
+import { createHash, randomBytes, timingSafeEqual } from "node:crypto";
+import type { FastifyRequest } from "fastify";
+
+export const SESSION_COOKIE = "companion_session";
+export const CSRF_COOKIE = "companion_csrf";
+
+export function randomToken(bytes = 32): string {
+  return randomBytes(bytes).toString("base64url");
+}
+
+export function hashToken(token: string): string {
+  return createHash("sha256").update(token).digest("hex");
+}
+
+export function safeEqual(left: string, right: string): boolean {
+  const leftBuffer = Buffer.from(left);
+  const rightBuffer = Buffer.from(right);
+  return leftBuffer.length === rightBuffer.length && timingSafeEqual(leftBuffer, rightBuffer);
+}
+
+export function clientAddress(request: FastifyRequest): string {
+  return request.ip.slice(0, 64);
+}