# OpenID Connect

Authentication | Users | Password
--- | --- | ---
✔ | ✔ |

## Presentation

Note

OpenID Connect is a protocol based on REST, OAuth 2.0 and JOSE stacks. It is described here: http://openid.net/connect/.

LL::NG can act as an OpenID Connect Relying Party (RP) towards multiple OpenID Connect Providers (OP). It will get the user identity through an ID Token, and grab user attributes through UserInfo endpoint.

As an RP, LL::NG supports many OpenID Connect features:

- Authorization Code, Implicit and Hybrid flows

- Automatic download of JWKS

- JWT signature verification

- Encrypted JWT (JWE)

- Access Token Hash verification

- ID Token validation

- Get UserInfo as JSON or as JWT

- Logout on EndSession endpoint

- Back Channel Logout

- Front Channel Logout

- RP-Initiated Logout

You can use this authentication module to link your LL::NG server to any OpenID Connect Provider. Here are some examples, with their specific documentation:

Google | France Connect | Pro Santé Connect
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Attention

OpenID Connect specification is not achieved for logout propagation. So logout initiated by relying-party will be forwarded to OpenID Connect provider but logout initiated by the provider (or another RP) will not be propagated. LL::NG will implement this when specification is published.

## Configuration

### OpenID Connect Service

See OpenID Connect service configuration chapter.

### Authentication and UserDB

In `General Parameters` > `Authentication modules`, set:

- Authentication module: OpenID Connect

- Users module: OpenID Connect

Tip

As passwords will not be managed by LL::NG, you can disable menu password module.

Attention

Browser implementations of formAction directive are inconsistent (e.g. Firefox does not block the redirects whereas Chrome does). Administrators may have to modify formAction value with wildcard likes *.

In Manager, go in:

`General Parameters` > `Advanced Parameters` > `Security` > `Content Security Policy` > `Form destination`

Then in `General Parameters` > `Authentication modules` > `OpenID Connect parameters`, you can set:

- Authentication level: authentication level associated to this module

- Callback GET parameter: name of the GET parameter used for intercepting callback (default: openidconnectcallback)

- State session timeout: duration of a state session (used for keeping state information between authentication request and authentication response) in seconds (default: 600)

### Register LL::NG to an OpenID Connect Provider

To register LL::NG, you will need to give some information like application name or logo.

You will be prompted to provide a Redirect URI for LL::NG, which is built by appending the `openidconnectcallback=1` parameter to the Portal URL.

For example:

- https://auth.example.com/?openidconnectcallback=1

Attention

If you use the choice backend, you need to set SameSite cookie value to “Lax” or “None”. See SSO cookie parameters

You may also be prompted for lougout type. LL::NG supports both back and front channels. Its default logout urls are:

- https://<portal>/oauth2/flogout for the Front Channel

- https://<portal>/oauth2/blogout for the Back Channel

Attention

Front Channel use requires “iss” and “sid” parameters in requests (See frontchannel_logout_session_required)

After registration, the OP must give you a Client ID and a Client secret required to configure the OP in LL::NG.

### Declare the OpenID Connect Provider in LL::NG

In Manager, select node `OpenID Connect Providers` and click on `Add OpenID Connect Provider`. Set a technical name (without space or special character) like “sample-op”.

You can then access to the configuration of this OP.

#### Metadata

The OP should publish its metadata in a JSON file (see for example Google metadata). Copy the content of this file in the textarea. Portal discovery document can be found here: https://#portal#/.well-known/openid-configuration

If no metadata is available, you need to write them in the textarea. Mandatory fields are:

- issuer

- authorization_endpoint

- token_endpoint

- userinfo_endpoint

You can also define:

- jwks_uri

- endsession_endpoint

Example template:

    {
      "issuer": "https://auth.example.com/",
      "authorization_endpoint": "https://auth.example.com/oauth2/authorize",
      "token_endpoint": "https://auth.example.com/oauth2/token",
      "userinfo_endpoint": "https://auth.example.com/oauth2/userinfo",
      "end_session_endpoint":"https://auth.example.com/oauth2/logout"
    }

#### JWKS data

JWKS is a JSON file containing public keys. LL::NG can grab them automatically if jwks_uri is defined in metadata. Else you can paste the JSON file content in the textarea.

Tip

If the OpenID Connect provider only uses symmetric encryption, JWKS data are useless.

#### Exported attributes

Define here mapping between LL::NG session content and fields provided in UserInfo endpoint response. These fields are defined in OpenID Connect standard, and depends on the scope requested by LL::NG (see options below).

So you can define by example:

- cn => name

- sn => family_name

- mail => email

- uid => sub

#### Options

##### Configuration

- PKCE required: A code challenge is required at Tokens endpoint (see RFC 7636)

- Store ID token: Allows one to store the ID Token (JWT) inside user session. Do not enable it unless you need to replay this token on an application, or if you need the id_token_hint parameter when using logout.

- Configuration endpoint: URL of OP configuration endpoint

- JWKS data timeout: After this time, LL::NG will do a request to get a fresh version of JWKS data. Set to 0 to disable it

- Client ID: client ID given by OP

- Client secret: client secret given by OP

- Attribute containing user identifier: Set the value of the ID Token claim that should be used as user main identifier. If empty, the `sub` claim is used.

##### Protocol

- Scope: Value of scope parameter (example: openid profile). The `openid` scope is mandatory.

- Display: Value of display parameter (example: page)

- Prompt: Value of prompt parameter (example: consent)

- Max age: Value of max_age parameter (example: 3600)

- Locales UI: Value of ui_locales parameter (example: en-GB en fr-FR fr)

- ACR values: Space-separated list of acceptable ACR values (example: ‘loa-2 loa-3’). Authentication will fail if the OpenID Provider does not supply one of the values listed here in the ID Token.

- Authentication method for authorization code request: Require JWS authentication for code requests

- Signature algorithm for authorization code authentication: Fix signature algorithm to be used for JWS authentication for code requests

- Token endpoint authentication method: choice between `client_secret_post`, `client_secret_basic`, `client_secret_jwt` and `private_key_jwt`

- Check JWT signature: Set to 0 to disable JWT signature checking

- ID Token max age: If defined, LL::NG will check the ID Token date and reject it if too old

- Use nonce: If enabled, a nonce will be sent, and verified from the ID Token

##### Comment: Set a comment

#### Display

Used only if at least 2 OIDC Providers are declared

- Name: Name of the OP

- Logo: Logo of the OP

- Tooltip: Information displayed on mouse over the button

- Resolution rule: Rule that will be applied to preselect an OP for a user. You have access to all environment variable (like user IP address) and all session keys.

For example, to preselect this OP for users coming from 129.168.0.0/16 network

    $ENV{REMOTE_ADDR} =~ /^192\.168/

To preselect this OP when the `MY_OP` choice is selected

    $_choice eq "MY_OP"

- Order: Used for sorting OP

Attention

With HTTPS authorization endpoint, you may have to set LWP::UserAgent object with `verify_hostname => 0` and `SSL_verify_mode => 0`.

Go to: `General Parameters > Advanced Parameters > Security > SSL options for server requests`

## Manual IDP Selection

When using multiple OpenID Providers, LemonLDAP::NG will display an additional choice screen to let the user decide which OP they want to use.

In addition to the resolution rule described above, you can also use the `idp` URL parameter to automatically select an OP for the user: `https://auth.example.com/?idp=op-example`