link are checking that email matches, +email alias are normalize into email
if email is already used on another account, link is not possible
not usurpation risk as the IDP is choosen by the admin
this make OIDC compliant with the invariant binding (issuer and subject)
admin can now rename their provider without breaking
clarifing federation_kind: report the kind of federation wired not the allowed login method
hybryd login method are still allowed
- POST /api/auth/opaque/login/ke1 (public) — takes {userIdentifier, startLoginRequest}, resolves the identifier via the same @-dispatch as legacy login (AuthApplicationService::lookup_user_for_login, factored out), fetches envelope, runs ServerLogin::start (real branch for known users, dummy branch for anti-enum on unknown/unregistered), stashes state under a random exchange_id in the moka cache, returns {exchangeId, loginResponse}.
- POST /api/auth/opaque/login/ke3 (public) — atomic take from the cache FIRST (anti-enum + anti-replay), then decodes the payload, runs ServerLogin::finish, stamps opaque_migrated_at (Phase 3 signal), and mints a session via the new AuthApplicationService::mint_session_for_authenticated_user helper — returns the same AuthResponseDto shape as legacy login so the SPA has one downstream handler.
- Session mint factored: mint_session_for_authenticated_user(User) extracted from login() so both the legacy password path and OPAQUE KE3 converge through one implementation.
- OpaqueRepositoryPort::mark_migrated with COALESCE-preserving idempotent stamp of opaque_migrated_at.
- opaque-setup CLI + Dockerfile wiring already shipped (Step 0 hygiene).
- Routing fix: sub-prefix split (/api/auth/opaque/register vs /api/auth/opaque/login) — axum composes middleware between sibling nests at the same prefix, which was cross-applying auth+CSRF to my public login routes. Distinct prefixes side-step that cleanly. Documented in both main.rs and the router builder doc.
- Rate-limit sharing: login KE1/KE3 layered with the SAME login_limiter instance as legacy POST /api/auth/login, so an attacker can't halve the per-IP budget by spraying both endpoints.
Anti-enum + anti-replay hardening in KE3: take runs BEFORE payload parse so:
- Unknown / expired / already-consumed exchange_id → 401 InvalidCredentials (same shape as wrong-passphrase, no payload-shape leak)
- Consumed handle can't be re-used to spam parse attempts
OPAQUE (RFC 9807) implementation (using `opaque-ke` crate)
with opaque authentfication, server will never receive the password (in the auth=password mode)
this is a must have to create trust with users to permit end to end encryption in the future
(we cannot know if user use the same password/passphrase for his asymetric key or his oxicloud auth,
this is why server must never have the password)
pass1: prepare server
Edouard Vanbelle