debian-mirror-gitlab/doc/integration/omniauth.md

---
stage: Manage
group: Authentication and Authorization
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/product/ux/technical-writing/#assignments
---

# OmniAuth **(FREE SELF)**

Users can sign in to GitLab by using their credentials from Twitter, GitHub, and other popular services.
[OmniAuth](https://rubygems.org/gems/omniauth/) is the Rack framework that GitLab uses to provide this authentication.

When configured, additional sign-in options are displayed on the sign-in page.

## Supported providers

GitLab supports the following OmniAuth providers.

| Provider documentation                                              | OmniAuth provider name     |
|---------------------------------------------------------------------|----------------------------|
| [AliCloud](alicloud.md)                                             | `alicloud`                 |
| [Atlassian](../administration/auth/atlassian.md)                    | `atlassian_oauth2`         |
| [Auth0](auth0.md)                                                   | `auth0`                    |
| [AWS Cognito](../administration/auth/cognito.md)                    | `cognito`                  |
| [Azure v2](azure.md)                                                | `azure_activedirectory_v2` |
| [Azure v1](azure.md)                                                | `azure_oauth2`             |
| [Bitbucket Cloud](bitbucket.md)                                     | `bitbucket`                |
| [DingTalk](ding_talk.md)                                            | `dingtalk`                |
| [Facebook](facebook.md)                                             | `facebook`                 |
| [Generic OAuth 2.0](oauth2_generic.md)                              | `oauth2_generic`           |
| [GitHub](github.md)                                                 | `github`                   |
| [GitLab.com](gitlab.md)                                             | `gitlab`                   |
| [Google](google.md)                                                 | `google_oauth2`            |
| [JWT](../administration/auth/jwt.md)                                | `jwt`                      |
| [Kerberos](kerberos.md)                                             | `kerberos`                 |
| [OpenID Connect](../administration/auth/oidc.md)                    | `openid_connect`           |
| [Salesforce](salesforce.md)                                         | `salesforce`               |
| [SAML](saml.md)                                                     | `saml`                     |
| [Twitter](twitter.md)                                               | `twitter`                  |

## Configure common settings

Before you configure the OmniAuth provider,
configure the settings that are common for all providers.

Linux package, Docker, and self-compiled | Helm chart | Description | Default value
----------------------------|------------|-------------|-----------
`allow_single_sign_on`     | `allowSingleSignOn` | List of providers that automatically create a GitLab account. The provider names are available in the **OmniAuth provider name** column in the [supported providers table](#supported-providers). | `false`, which means that signing in using your OmniAuth provider account without a pre-existing GitLab account is not allowed. You must create a GitLab account first, and then connect it to your OmniAuth provider account through your profile settings.
`auto_link_ldap_user`      | `autoLinkLdapUser` | Creates an LDAP identity in GitLab for users that are created through an OmniAuth provider. You can enable this setting if you have [LDAP integration](../administration/auth/ldap/index.md) enabled. Requires the `uid` of the user to be the same in both LDAP and the OmniAuth provider. | `false`
`block_auto_created_users` | `blockAutoCreatedUsers` | Blocks users that are automatically created from signing in until they are approved by an administrator. | `true`. If you set the value to `false`, make sure you define providers that you can control, like SAML or Google. Otherwise, any user on the internet can sign in to GitLab without an administrator's approval.

### Configure initial settings

To change the OmniAuth settings:

  ::Tabs

  :::TabTitle Linux package (Omnibus)

  1. Edit `/etc/gitlab/gitlab.rb`:

     ```ruby
     # CAUTION!
     # This allows users to sign in without having a user account first. Define the allowed providers
     # using an array, for example, ["saml", "twitter"], or as true/false to allow all providers or none.
     # User accounts will be created automatically when authentication was successful.
     gitlab_rails['omniauth_allow_single_sign_on'] = ['saml', 'twitter']
     gitlab_rails['omniauth_auto_link_ldap_user'] = true
     gitlab_rails['omniauth_block_auto_created_users'] = true
     ```

  1. Save the file and reconfigure GitLab:

     ```shell
     sudo gitlab-ctl reconfigure
     ```

  :::TabTitle Helm chart (Kubernetes)

  1. Export the Helm values:

     ```shell
     helm get values gitlab > gitlab_values.yaml
     ```

  1. Edit `gitlab_values.yaml`, and update the `omniauth` section under `globals.appConfig`:

     ```yaml
     global:
       appConfig:
         omniauth:
           enabled: true
           allowSingleSignOn: ['saml', 'twitter']
           autoLinkLdapUser: false
           blockAutoCreatedUsers: true
     ```

     For more details, see the
     [globals documentation](https://docs.gitlab.com/charts/charts/globals.html#omniauth).

  1. Save the file and apply the new values:

     ```shell
     helm upgrade -f gitlab_values.yaml gitlab gitlab/gitlab
     ```

  :::TabTitle Docker

  1. Edit `docker-compose.yml`:

     ```yaml
     version: "3.6"
     services:
       gitlab:
         environment:
           GITLAB_OMNIBUS_CONFIG: |
             gitlab_rails['omniauth_allow_single_sign_on'] = ['saml', 'twitter']
             gitlab_rails['omniauth_auto_link_ldap_user'] = true
             gitlab_rails['omniauth_block_auto_created_users'] = true
     ```

  1. Save the file and restart GitLab:

     ```shell
     docker compose up -d
     ```

  :::TabTitle Self-compiled (source)

  1. Edit `/home/git/gitlab/config/gitlab.yml`:

     ```yaml
     ## OmniAuth settings
     omniauth:
       # Allow sign-in by using Twitter, Google, etc. using OmniAuth providers
       # Versions prior to 11.4 require this to be set to true
       # enabled: true

       # CAUTION!
       # This allows users to sign in without having a user account first. Define the allowed providers
       # using an array, for example, ["saml", "twitter"], or as true/false to allow all providers or none.
       # User accounts will be created automatically when authentication was successful.
       allow_single_sign_on: ["saml", "twitter"]

       auto_link_ldap_user: true

       # Locks down those users until they have been cleared by the admin (default: true).
       block_auto_created_users: true
     ```

  1. Save the file and restart GitLab:

     ```shell
     # For systems running systemd
     sudo systemctl restart gitlab.target

     # For systems running SysV init
     sudo service gitlab restart
     ```

  ::EndTabs

After configuring these settings, you can configure
your chosen [provider](#supported-providers).

### Per-provider configuration

> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/89379) in GitLab 15.3.

If `allow_single_sign_on` is set, GitLab uses one of the following fields returned in the OmniAuth `auth_hash` to establish a username in GitLab for the user signing in,
choosing the first that exists:

- `username`.
- `nickname`.
- `email`.

You can create GitLab configuration on a per-provider basis, which is supplied to the [provider](#supported-providers) using `args`. If you set the `gitlab_username_claim`
variable in `args` for a provider, you can select another claim to use for the GitLab username. The chosen claim must be unique to avoid collisions.

- **For Omnibus installations**

  ```ruby
  gitlab_rails['omniauth_providers'] = [

    # The generic pattern for configuring a provider with name PROVIDER_NAME

    gitlab_rails['omniauth_providers'] = {
      name: "PROVIDER_NAME"
      ...
      args: { gitlab_username_claim: 'sub' } # For users signing in with the provider you configure, the GitLab username will be set to the "sub" received from the provider
    },

    # Here are examples using GitHub and Kerberos

    gitlab_rails['omniauth_providers'] = {
      name: "github"
      ...
      args: { gitlab_username_claim: 'name' } # For users signing in with GitHub, the GitLab username will be set to the "name" received from GitHub
    },
    {
      name: "kerberos"
      ...
      args: { gitlab_username_claim: 'uid' } # For users signing in with Kerberos, the GitLab username will be set to the "uid" received from Kerberos
    },
  ]
  ```

- **For installations from source**

  ```yaml
  - { name: 'PROVIDER_NAME',
    ...
    args: { gitlab_username_claim: 'sub' }
  }
  - { name: 'github',
    ...
    args: { gitlab_username_claim: 'name' }
  }
  - { name: 'kerberos',
    ...
    args: { gitlab_username_claim: 'uid' }
  }
  ```

### Passwords for users created via OmniAuth

The [Generated passwords for users created through integrated authentication](../security/passwords_for_integrated_authentication_methods.md)
guide provides an overview about how GitLab generates and sets passwords for
users created with OmniAuth.

## Enable OmniAuth for an existing user

If you're an existing user, after your GitLab account is
created, you can activate an OmniAuth provider. For example, if you originally signed in with LDAP, you can enable an OmniAuth
provider like Twitter.

1. Sign in to GitLab with your GitLab credentials, LDAP, or another OmniAuth provider.
1. On the top bar, in the upper-right corner, select your avatar.
1. Select **Edit profile**.
1. On the left sidebar, select **Account**.
1. In the **Connected Accounts** section, select the OmniAuth provider, such as Twitter.
1. You are redirected to the provider. After you authorize GitLab,
   you are redirected back to GitLab.

You can now use your chosen OmniAuth provider to sign in to GitLab.

## Enable or disable sign-in with an OmniAuth provider without disabling import sources

Administrators can enable or disable sign-in for some OmniAuth providers.

NOTE:
By default, sign-in is enabled for all the OAuth providers configured in `config/gitlab.yml`.

To enable or disable an OmniAuth provider:

1. On the top bar, select **Main menu > Admin**.
1. On the left sidebar, select **Settings**.
1. Expand **Sign-in restrictions**.
1. In the **Enabled OAuth authentication sources** section, select or clear the checkbox for each provider you want to enable or disable.

## Disable OmniAuth

OmniAuth is enabled by default. However, OmniAuth only works
if providers are configured and [enabled](#enable-or-disable-sign-in-with-an-omniauth-provider-without-disabling-import-sources).

If OmniAuth providers are causing problems even when individually disabled, you
can disable the entire OmniAuth subsystem by modifying the configuration file:

- **For Omnibus installations**

  ```ruby
  gitlab_rails['omniauth_enabled'] = false
  ```

- **For installations from source**

  ```yaml
  omniauth:
    enabled: false
  ```

## Link existing users to OmniAuth users

> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/36664) in GitLab 13.4.

You can automatically link OmniAuth users with existing GitLab users if their email addresses match.

The following example enables automatic linking
for the OpenID Connect provider and the Twitter OAuth provider.

- **For Omnibus installations**

  ```ruby
  gitlab_rails['omniauth_auto_link_user'] = ["openid_connect", "twitter"]
  ```

- **For installations from source**

  ```yaml
  omniauth:
    auto_link_user: ["openid_connect", "twitter"]
  ```

This method of enabling automatic linking works for all providers
[except SAML](https://gitlab.com/gitlab-org/gitlab/-/issues/338293).
To enable automatic linking for SAML, see the [SAML setup instructions](saml.md#configure-saml-support-in-gitlab).

## Create an external providers list

You can define a list of external OmniAuth providers.
Users who create accounts or sign in to GitLab through the listed providers do not get access to [internal projects](../user/public_access.md#internal-projects-and-groups) and are marked as [external users](../user/admin_area/external_users.md).

To define the external providers list, use the full name of the provider,
for example, `google_oauth2` for Google. For provider names, see the
**OmniAuth provider name** column in the [supported providers table](#supported-providers).

NOTE:
If you remove an OmniAuth provider from the external providers list,
you must manually update the users that use this sign-in method so their
accounts are upgraded to full internal accounts.

- **For Omnibus installations**

  ```ruby
  gitlab_rails['omniauth_external_providers'] = ['twitter', 'google_oauth2']
  ```

- **For installations from source**

  ```yaml
  omniauth:
    external_providers: ['twitter', 'google_oauth2']
  ```

## Use a custom OmniAuth provider

NOTE:
The following information only applies to installations from source.

If you have to integrate with an authentication solution other than the [OmniAuth](https://github.com/omniauth/omniauth) providers included with GitLab,
you can use a custom OmniAuth provider.

These steps are general. Read the OmniAuth provider's documentation for the exact
implementation details.

1. Stop GitLab:

   ```shell
   sudo service gitlab stop
   ```

1. Add the gem to your [`Gemfile`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/Gemfile):

   ```shell
   gem "omniauth-your-auth-provider"
   ```

1. Install the new OmniAuth provider gem:

   ```shell
   sudo -u git -H bundle install --without development test mysql --path vendor/bundle --no-deployment
   ```

   These commands are the same as the commands for [installing gems](../install/installation.md#install-gems)
   during initial installation, with `--path vendor/bundle --no-deployment` instead of `--deployment`.

1. Start GitLab:

   ```shell
   sudo service gitlab start
   ```

### Custom OmniAuth provider examples

If you have successfully set up a provider that is not already integrated with GitLab,
let us know.

We can't officially support every possible authentication mechanism available,
but we'd like to at least help those with specific needs.

## Keep OmniAuth user profiles up to date

You can enable profile syncing from selected OmniAuth providers.
You can sync any combination of the following user attributes:

- `name`
- `email`
- `location`

When authenticating using LDAP, the user's name and email are always synced.

- **For Omnibus installations**

  ```ruby
  gitlab_rails['omniauth_sync_profile_from_provider'] = ['twitter', 'google_oauth2']
  gitlab_rails['omniauth_sync_profile_attributes'] = ['name', 'email', 'location']
  ```

- **For installations from source**

  ```yaml
  omniauth:
    sync_profile_from_provider: ['twitter', 'google_oauth2']
    sync_profile_attributes: ['email', 'location']
  ```

## Bypass two-factor authentication

> Introduced in GitLab 12.3.

With certain OmniAuth providers, users can sign in without using two-factor authentication (2FA).

Because of a [known issue](https://gitlab.com/gitlab-org/gitlab/-/issues/196131) users must
[set up 2FA](../user/profile/account/two_factor_authentication.md#enable-two-factor-authentication) on their GitLab
account to bypass 2FA. Otherwise, they are prompted to set up 2FA when they sign in to GitLab.

To bypass 2FA, you can either:

- Define the allowed providers using an array (for example, `['twitter', 'google_oauth2']`).
- Specify `true` to allow all providers, or `false` to allow none.

This option should be configured only for providers that already have 2FA. The default is `false`.

This configuration doesn't apply to SAML.

- **For Omnibus package**

  ```ruby
  gitlab_rails['omniauth_allow_bypass_two_factor'] = ['twitter', 'google_oauth2']
  ```

- **For installations from source**

  ```yaml
  omniauth:
    allow_bypass_two_factor: ['twitter', 'google_oauth2']
  ```

## Sign in with a provider automatically

You can add the `auto_sign_in_with_provider` setting to your GitLab
configuration to redirect login requests to your OmniAuth provider for
authentication. This removes the need to select the provider before signing in.

For example, to enable automatic sign-in for the
[Azure v2 integration](azure.md):

- **For Omnibus package**

  ```ruby
  gitlab_rails['omniauth_auto_sign_in_with_provider'] = 'azure_activedirectory_v2'
  ```

- **For installations from source**

  ```yaml
  omniauth:
    auto_sign_in_with_provider: azure_activedirectory_v2
  ```

Keep in mind that every sign-in attempt is redirected to the OmniAuth
provider, so you can't sign in using local credentials. Ensure at least
one of the OmniAuth users is an administrator.

You can also bypass automatic sign-in by browsing to
`https://gitlab.example.com/users/sign_in?auto_sign_in=false`.

## Use a custom OmniAuth provider icon

Most supported providers include a built-in icon for the rendered sign-in button.

To use your own icon, ensure your image is optimized for rendering at 64 x 64 pixels,
then override the icon in one of two ways:

- **Provide a custom image path**:

  1. If you are hosting the image outside of your GitLab server domain, ensure
     your [content security policies](https://docs.gitlab.com/omnibus/settings/configuration.html#content-security-policy)
     are configured to allow access to the image file.
  1. Depending on your method of installing GitLab, add a custom `icon` parameter
     to your GitLab configuration file. Read [OpenID Connect OmniAuth provider](../administration/auth/oidc.md)
     for an example for the OpenID Connect provider.

- **Embed an image directly in a configuration file**: This example creates a Base64-encoded
  version of your image you can serve through a
  [Data URL](https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/Data_URIs):

  1. Encode your image file with a GNU `base64` command (such as `base64 -w 0 <logo.png>`)
     which returns a single-line `<base64-data>` string.
  1. Add the Base64-encoded data to a custom `icon` parameter in your GitLab
     configuration file:

     ```yaml
     omniauth:
       providers:
         - { name: '...'
             icon: 'data:image/png;base64,<base64-data>'
             ...
           }
     ```

## Change apps or configuration

Because OAuth in GitLab doesn't support setting the same external authentication and authorization provider as multiple providers, GitLab configuration and
user identification must be updated at the same time if the provider or app is changed.
For example, you can set up `saml` and `azure_activedirectory_v2` but cannot add a second `azure_activedirectory_v2` to the same configuration.

These instructions apply to all methods of authentication where GitLab stores an `extern_uid` and it is the only data used
for user authentication.

When changing apps within a provider, if the user `extern_uid` does not change, only the GitLab configuration must be
updated.

To swap configurations:

1. Change provider configuration in your `gitlab.rb` file.
1. Update `extern_uid` for all users that have an identity in GitLab for the previous provider.

To find the `extern_uid`, look at an existing user's current `extern_uid` for an ID that matches the appropriate field in
your current provider for the same user.

There are two methods to update the `extern_uid`:

- Using the [Users API](../api/users.md#user-modification). Pass the provider name and the new `extern_uid`.
- Using the [Rails console](../administration/operations/rails_console.md):

  ```ruby
  Identity.where(extern_uid: 'old-id').update!(extern_uid: 'new-id')`
  ```

## Known issues

Most supported OmniAuth providers don't support Git over HTTP password authentication.
As a workaround, you can authenticate using a [personal access token](../user/profile/personal_access_tokens.md).