#5036 "SSO and LDAP: users keep their auth source, no merging into local
accounts, is_active checked, LDAP TLS real and filter escaped".
- users gain auth_source (local/ldap/oidc) and external_id (migration 0027).
A provider account is found by (source, subject) only: the LDAP entry DN
or the OIDC sub. A first sign-in whose username or email another account
holds is refused with a message naming why; a disabled user stays out.
- Local passwords sign in local accounts only.
- LDAP: port 636 is LDAPS, otherwise StartTLS before any bind; the server
certificate is checked against the system CAs or a CA pasted in
Settings -> Auth. The login name is escaped into the filter (RFC 4515),
and an empty password is refused before the directory sees it.
- OIDC: the ID token must carry this sign-in's nonce and the userinfo sub.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
