Files
netris-nestri/packages/auth
Wanjohi 49ae45624e fix(auth): a host may receive a code at its own name, and a refusal is not a redirect
Two changes to who may start a flow here, and where a refusal is delivered.

A host reached at its own hostname sits on a different registrable domain from
this issuer, deliberately: that is what stops a cookie set there from ever
reaching this one. The default rule allows a redirect back to whatever hostname
the request arrived on, so it refused exactly the case the separation created.
Which is a real problem rather than a theoretical one, because a session cookie
without a Domain attribute is host-only, so a browser arriving at one of those
hostnames for the first time carries no cookie whether or not it is signed in,
and sending it here to sign in again changes nothing.

So a client id that is a single hostname under that zone, whose redirect_uri is
https and that same hostname at one reserved path, is allowed. Making the
client id the hostname is the load-bearing part: a token's audience is its
client id, so the session that comes back is bound to the host it will live on
and is not a credential anywhere else.

Separately, and worth its own paragraph: a refused client's redirect_uri was
still used to report the refusal. The check that approves that URI is the one
that just failed, so /authorize was an open redirector to anywhere at all --
no sign-in required, on the hostname people are asked to type a password into.
It is now a page here. Before:

  GET /authorize?client_id=web&redirect_uri=https://somewhere.example/callback
  -> 302 https://somewhere.example/callback?error=unauthorized_client
2026-09-06 23:44:51 +03:00
..
2026-08-06 22:13:51 +03:00
2026-08-06 22:13:51 +03:00
2026-08-06 22:32:33 +03:00
2026-08-06 22:13:51 +03:00

packages/auth (@nestri/auth)

Framework-agnostic OpenAuth implementation for Nestri — the OAuth/OIDC issuer, client, subjects, and the login UI. A vendored/forked build of OpenAuth.

What it does

Everything needed to run your own authentication provider:

  • issuer.ts — the authorization server: routes for /authorize, /callback, /token, /userinfo, .well-known/*, plus the login UI (React renderer).
  • client.tscreateClient to verify JWTs against the issuer ("who is this token?").
  • subject.ts — typed JWT subjects (zod schemas for the token payload).
  • provider/* — drop-in OAuth/OIDC providers (steam, discord, github, google, apple, microsoft, slack, spotify, twitch, x, yahoo, facebook, linkedin, cognito, keycloak, jumpcloud, oauth2, oidc, password, ssh, code, arctic).
  • storage/* — persistence adapters for keys/sessions/codes: memory, cloudflare (KV), aws, dynamo.
  • ui/* — the login page components (forms, password, code, theme, CSS).
  • jwt.ts, keys.ts, pkce.ts, random.ts — signing, keypair management, PKCE, randomness.

Usage

Consumed by the apps/auth worker, e.g.:

import { issuer } from '@nestri/auth/index';
import { CloudflareStorage } from '@nestri/auth/storage/cloudflare';
import { SteamProvider } from '@nestri/auth/provider/steam';

The API uses createClient (from @openauth/openauth/client) or the bundled client.ts to verify tokens against the issuer URL.

Scripts

bun test      # run tests
bun run build # build (see script/build.ts)

Note

@openauthjs is the upstream project; this package's exports are meant to be API-compatible with a pinned preference toward tree-shaking-friendly imports. Prefer importing subpaths over the barrel (@nestri/auth/index).