85 lines
4.2 KiB
Markdown
85 lines
4.2 KiB
Markdown
# Architecture
|
|
|
|
## Online authentication
|
|
|
|
```text
|
|
LogonUI
|
|
-> SGU Credential Provider (SecureString)
|
|
-> HTTPS 1.1 + client certificate
|
|
-> SGU Auth Broker
|
|
-> SGU IIS NTLM endpoint (original password)
|
|
-> minimum SGU profile metadata (same authenticated response)
|
|
-> Active Directory (same original password + optional profile)
|
|
<- domain + canonical username; never a password
|
|
-> Windows credential serialization (original SecureString)
|
|
-> LSA / Kerberos / cached domain logon
|
|
```
|
|
|
|
The broker performs the NTLM exchange and AD update before returning `200 OK`.
|
|
It follows only HTTPS redirects whose host appears in `AllowedRedirectHosts`,
|
|
which prevents credential forwarding to an unexpected redirect target. HTTP/1.1
|
|
is forced because NTLM authentication is connection-bound.
|
|
|
|
The logical GET is sent directly to the administrative incident overview for
|
|
`AD` identities or to the portal menu for `DO`/`AL` identities. NTLM may still
|
|
require its normal challenge/response round trips on that connection. The
|
|
broker keeps any transient portal cookie in an in-memory per-request container;
|
|
it is never persisted or returned to the client.
|
|
|
|
## Offline authentication
|
|
|
|
```text
|
|
Broker timeout, TLS failure, 429, or 5xx
|
|
-> provider preserves the entered username/password
|
|
-> Windows LSA validates against AD or its cached domain verifier
|
|
-> only the last AD password succeeds
|
|
```
|
|
|
|
An explicit `400` or `401` from the broker is different: the provider displays
|
|
an error and does not serialize the rejected credential.
|
|
|
|
## Account synchronization
|
|
|
|
The broker normalizes the username to uppercase and accepts exactly two letters
|
|
plus six digits. It searches `BaseDn` by `sAMAccountName`, creates the user when
|
|
absent, moves it to the mapped OU when required, sets `userPrincipalName`, and
|
|
passes the submitted password directly to ADSI `SetPassword`.
|
|
|
|
When the authenticated HTML exposes recognized stable IDs, the broker also
|
|
updates `displayName`, `mail`, `title`, `department`, `employeeType`, and
|
|
`employeeID`. The administrative employee number must match the six numeric
|
|
digits of the requested `AD` identity before any scraped metadata is trusted.
|
|
Missing metadata does not clear existing AD values and never changes the
|
|
password outcome.
|
|
|
|
Human-readable SGU values are decoded with BOM/header/meta detection, strict
|
|
UTF-8 validation, and a Windows-1252 fallback for the legacy portal. Names and
|
|
titles are normalized with Spanish-aware casing; particles such as `de`, `del`
|
|
and `de la` remain lowercase and Unicode accents are preserved. Values that
|
|
still contain the Unicode replacement character are not written to AD.
|
|
|
|
When `RemoteDesktopGroupDn` is configured, the broker also adds each successfully
|
|
synchronized SGU user to that dedicated AD security group. The laboratory
|
|
Windows client maps the group into its local **Remote Desktop Users** group.
|
|
Every synchronized user also receives `Universidad La Salle` in the AD
|
|
`company` attribute unless deployment configuration supplies another default.
|
|
|
|
The generic SGU credential is rendered as a dedicated branded tile instead of
|
|
being grouped below the anonymous **Other user** tile. Machine policy assigns
|
|
the SGU CLSID as the default provider while retaining the built-in Microsoft
|
|
password provider. It enumerates one `CPFT_TILE_IMAGE` and places the
|
|
`CPFT_LARGE_TEXT` heading immediately after it with `CPFS_DISPLAY_IN_BOTH`,
|
|
matching Microsoft's supported field ordering. LogonUI owns field typography:
|
|
on Windows 10 and 11, the account-name title used by **Other user** is shell UI,
|
|
not a style that a generic Credential Provider can request. Do not add a second
|
|
tile image or a synthetic Windows account to imitate that title.
|
|
|
|
The managed hierarchy is rooted at `OU=Usuarios-SGU`: `Docentes`, `Alumnos`,
|
|
and `Administrativos` are direct child OUs beneath it.
|
|
|
|
Per-user synchronization is serialized inside the broker to prevent concurrent
|
|
create/reset races. Production deployments should run the broker as a gMSA with
|
|
delegated create-user, move-user, write-property, enable-account, and reset-password
|
|
rights limited to `Usuarios-SGU` and its three managed child OUs. The lab can run it on the domain
|
|
controller as LocalSystem.
|