- Example for Microsoft Active Directory (AD): `(&(objectCategory=Person)(memberOf=CN=user-group,OU=example,DC=example,DC=org)(sAMAccountName=%s)(!(UserAccountControl:1.2.840.113556.1.4.803:=2)))`
## SPNEGO with SSPI (Kerberos/NTLM, for Windows only)
Gitea supports SPNEGO single sign-on authentication (the scheme defined by RFC4559) for the web part of the server via the Security Support Provider Interface (SSPI) built in Windows. SSPI works only in Windows environments - when both the server and the clients are running Windows.
Before activating SSPI single sign-on authentication (SSO) you have to prepare your environment:
- Create a separate user account in active directory, under which the `gitea.exe` process will be running (eg. `user` under domain `domain.local`):
- Create a service principal name for the host where `gitea.exe` is running with class `HTTP`:
- Start `Command Prompt` or `PowerShell` as a priviledged domain user (eg. Domain Administrator)
- Run the command below, replacing `host.domain.local` with the fully qualified domain name (FQDN) of the server where the web application will be running, and `domain\user` with the name of the account created in the previous step:
```
setspn -A HTTP/host.domain.local domain\user
```
- Sign in (*sign out if you were already signed in*) with the user created
- Make sure that `ROOT_URL` in the `[server]` section of `custom/conf/app.ini` is the fully qualified domain name of the server where the web application will be running - the same you used when creating the service principal name (eg. `host.domain.local`)
- Start the web server (`gitea.exe web`)
- Enable SSPI authentication by adding an `SPNEGO with SSPI` authentication source in `Site Administration -> Authentication Sources`
- Sign in to a client computer in the same domain with any domain user (client computer, different from the server running `gitea.exe`)
- Click the `Sign In` button on the dashboard and choose SSPI to be automatically logged in with the same user that is currently logged on to the computer
- If it does not work, make sure that:
- You are not running the web browser on the same server where gitea is running. You should be running the web browser on a domain joined computer (client) that is different from the server. If both the client and server are runnning on the same computer NTLM will be prefered over Kerberos.
- There is only one `HTTP/...` SPN for the host
- The SPN contains only the hostname, without the port
- You have added the URL of the web app to the `Local intranet zone`
- The clocks of the server and client should not differ with more than 5 minutes (depends on group policy)
-`Integrated Windows Authentication` should be enabled in Internet Explorer (under `Advanced settings`)