/aad-sso-wordpress

Single Sign-on with Azure Active Directory (for WordPress)

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Sign Sign-on with Azure Active Directory (for WordPress)

A WordPress plugin that allows organizations to use their Azure Active Directory user accounts to sign in to WordPress. Organizations with Office 365 already have Azure Active Directory (Azure AD) and can use this plugin for all of their users.

  • Azure AD group membership can be used to determine access and role.
  • New users can be registered on-the-fly based on their Azure AD profile.
  • Can always fall back to regular username and password login.

This is a work in progress, please feel free to contact me for help. This plugin is provided as-is, with no guarantees or assurances.

In the typical flow:

  1. User attempts to log in to the blog (wp-admin). At the sign in page, they are given a link to sign in with their Azure Active Directory organization account (e.g. an Office 365 account).
  2. After signing in, the user is redirected back to the blog with an authorization code, which the plugin exchanges for a ID Token, containing a minimal set of claims about the signed in user, and an Access Token, which can be used to query Azure AD for additional details.
  3. The plugin uses the claims in the ID Token to attempt to find a WordPress user with an email address or login name that matches the Azure AD user.
  4. If one is found, the user is authenticated in WordPress as that user. If one is not found, the WordPress user will (optionally) be auto-provisioned on-the-fly.
  5. (Optional) Membership to certain groups in Azure AD can be mapped to roles in WordPress, and group membership can be used to restrict access.

Getting Started

The following instructions will get you started. In this case, we will be configuring the plugin to use the user roles configured in WordPress.

1. Download and activate the plugin

This plugin is not yet registered in the WordPress plugin directory (coming soon!), but you can still install it manually:

  1. Download the plugin using git or with the 'Download ZIP' link on the right.
  2. Place the aad-sso-wordpress folder in your WordPress' plugin folder. Normally, this is <your-blog>/wp-content/plugins.
  3. Activate the plugin in the WordPress admin console, under Plugins > Installed Plugins.

2. Register an Azure Active Directory application

With these steps, you will register an application with Azure AD. This application identifies your WordPress site with Azure AD.

  1. Sign in to the Azure portal, and ensure you are signed in to the directory which has the users you'd like to allow to sign in. (This will typically be your organization's directory.) You can view which directory you're signed in to (and switch directories if needed) by clicking on your username in the upper right-hand corner.

  2. Navigate to the Azure Active Directory blade, and enter the App registrations section.

    Clicking Azure Active Directory
    Clicking App registrations

  3. Choose New application registration, and provide a name for your app. This will be the name displayed to users when signing in. Leave the default application type ("Web app / API"), provide the URL of your site as the "Sign-on URL", and click Create. When the app is created, select the newly-registered app from the list.

    Clicking New application registration
    Creating new application
    Selecting the newly-created app

  4. Under Reply URLs, update the existing reply URL with the format: https://<your blog url>/wp-login.php, or whichever page your blog uses to sign in users, and click Save. (Note: This page must invoke the authenticate action.)

    Adding a reply URL

  5. Under Required permissions, choose the "Windows Azure Active Directory" API. You will need at minimum delegated permissions to "Sign in and read user profile". If you wish to map Azure AD groups to WordPress roles, you will also need delegated permission to "Read directory data". Once you've selected the permissions, click Save.

    Important: The "Read directory data" delegated permissions requires a tenant administrator to consent to the application. The tenant administrator can use the Grant Permissions option to grant permissions (i.e. consent) on behalf of all users.

    Delegated permissions to sign in and read directory data

  6. Under Keys, provide a new secret key description and duration, and click Save. After saving, the secret key value will appear. Copy it, as this is the only time it will be available.

    Creating a new secret key

  7. Keep a tab open with the app registration page, as you will need to copy some fields when configuring the plugin.

    App settings summary page

3. Configure the plugin

Once the plugin is activated, update your settings from the WordPress admin console under Settings > Azure AD. Basic settings to include are:

Display name
The display name of the organization, used only in the link in the login page.
Client ID
The Application ID. (Copy this from Azure AD application's configuration page.)
Client Secret
The secret key. (Copy this from the Azure AD application's configuration page.)
Reply URL
The URL that Azure AD will send the user to after authenticating. This is usually the blog's sign-in page, which is the default value. Ensure that the reply URL configured in Azure AD matches this value.

4. (Optional) Set WordPress roles based on Azure AD group membership

The Single Sign-on with Azure AD plugin can be configured to set different WordPress roles based on the user's membership to a set of user-defined groups. This is a great way to control who has access to the blog, and under what role.

This is also configured Settings > Azure AD (from the WordPress admin console). The following fields should be included:

Enable Azure AD group to WP role association
Check this to enable Azure AD group-based WordPress roles.
Default WordPress role if not in Azure AD group
This is the default role that users will be assigned to if matching Azure AD group to WordPress roles is enabled. If this is not set, and the user authenticating does not belong to any of the groups defined, they will be denied access.
WordPress role to Azure AD group map
For each of the blog's WordPress roles, there is a field for the ObjectId of the Azure AD group that will be associated with that role.

Example settings

The different fields that can be defined in the settings JSON in Settings > Azure AD are documented in Settings.php. The following may give you an idea of the typical scenarios that may be encountered.

Minimal

Users are matched by their email address in WordPress, and whichever role they have in WordPress is maintained.

Setting Example value
Display name Contoso
Client ID 9054eff5-bfef-4cc5-82fd-8c35534e48f9
Client Secret NTY5MmE5YjMwMGY2MWQ0NjU5MzYxNjdjNzE1OGNiZmY=
Reply URL https://www.example.com/blog/wp-login.php
Field to match to UPN Email Address

Match on username alias

Users are matched by their login names in WordPress and the alias portion of their Azure AD UserPrincipalName. Whichever role they have in WordPress is maintained.

Setting Example value
Display name Contoso
Client ID 9054eff5-bfef-4cc5-82fd-8c35534e48f9
Client Secret NTY5MmE5YjMwMGY2MWQ0NjU5MzYxNjdjNzE1OGNiZmY=
Reply URL https://www.example.com/blog/wp-login.php
Field to match to UPN Login Name
Match on alias of the UPN Yes

Group membership-based roles, no default role

Users are matched by their login names in WordPress, and WordPress roles are dictated by membership to a given Azure AD group. Access is denied if they are not members of any of these groups.

Setting Example value
Display name Contoso
Client ID 9054eff5-bfef-4cc5-82fd-8c35534e48f9
Client Secret NTY5MmE5YjMwMGY2MWQ0NjU5MzYxNjdjNzE1OGNiZmY=
Reply URL https://www.example.com/blog/wp-login.php
Field to match to UPN Login Name
Enable Azure AD group to WP role association Yes
Default WordPress role if not in Azure AD group (None, deny access)
WordPress role to Azure AD group map
Administrator5d1915c4-2373-42ba-9796-7c092fa1dfc6
Editor21c0f87b-4b65-48c1-9231-2f9295ef601c
Authorf5784693-11e5-4812-87db-8c6e51a18ffd
Contributor780e055f-7e64-4e34-9ff3-012910b7e5ad
Subscriberf1be9515-0aeb-458a-8c0a-30a03c1afb67

Group membership-based roles with default role

Users are matched by their login names in WordPress, and WordPress roles are dictated by membership to a given Azure AD group. If the user is not a part of any of these groups, they are assigned the Author role.

Setting Example value
Display name Contoso
Client ID 9054eff5-bfef-4cc5-82fd-8c35534e48f9
Client Secret NTY5MmE5YjMwMGY2MWQ0NjU5MzYxNjdjNzE1OGNiZmY=
Reply URL https://www.example.com/blog/wp-login.php
Field to match to UPN Login Name
Enable Azure AD group to WordPress role association Yes
Default WordPress role if not in Azure AD group Author
WordPress role to Azure AD group map
Administrator5d1915c4-2373-42ba-9796-7c092fa1dfc6
Editor21c0f87b-4b65-48c1-9231-2f9295ef601c
Authorf5784693-11e5-4812-87db-8c6e51a18ffd
Contributor780e055f-7e64-4e34-9ff3-012910b7e5ad
Subscriberf1be9515-0aeb-458a-8c0a-30a03c1afb67

Group membership-based roles, default role, auto-provision

Users are matched by their email in WordPress, and WordPress roles are dictated by membership to a given Azure AD group. If the user doesn't exist in WordPress yet, they will be auto-provisioned. If the user is not a part of any of these groups, they are assigned the Subscriber role.

Setting Example value
Display name Contoso
Client ID 9054eff5-bfef-4cc5-82fd-8c35534e48f9
Client Secret NTY5MmE5YjMwMGY2MWQ0NjU5MzYxNjdjNzE1OGNiZmY=
Reply URL https://www.example.com/blog/wp-login.php
Field to match to UPN Email Address
Enable auto-provisioning Yes
Enable Azure AD group to WP role association Yes
Default WordPress role if not in Azure AD group Subscriber
WordPress role to Azure AD group map
Administrator5d1915c4-2373-42ba-9796-7c092fa1dfc6
Editor21c0f87b-4b65-48c1-9231-2f9295ef601c
Authorf5784693-11e5-4812-87db-8c6e51a18ffd
Contributor780e055f-7e64-4e34-9ff3-012910b7e5ad
Subscriberf1be9515-0aeb-458a-8c0a-30a03c1afb67

Groups

As described above, you can map Azure AD groups to WordPress roles. Users who are members of the Azure AD group will be granted the WordPress role(s) the groups were mapped to.

There are several ways Azure AD groups can be created/managed. Some of them require the group owner/creator to be a tenant administrator, others not necessarily (depending on your organization's policy):

Advanced

Refreshing the OpenID Connect configuration cache

Most of the OpenID Connect endpoints and configuration (e.g. signing keys, etc.) are obtained from the OpenID Connect configuration endpoint. These values are cached for one hour, but can always be forced to re-load by adding aadsso_reload_openid_config=1 to the query string in the login page. (This shouldn't really be needed, but it has shown to be useful during development.)

Bypassing automatic redirect to Azure AD to prevent lockouts

If you've configured this plugin to automatically redirect to Azure AD for sign-in, but something is misconfigured, you may find yourself locked out of your site's admin dashboard.

To log in to your site without automatically redirecting to Azure AD (thus giving you an opportunity to enter a regular username and password), you can append ?aadsso_no_redirect=please to the login URL. For example, if your login URL is https://example.com/wp-login.php, navigating to https://example.com/wp-login.php?aadsso_no_redirect=please will prevent any automatic redirects.