authentik/website/docs/integrations/services/nextcloud/index.md

title
NextCloud

What is NextCloud

From https://en.wikipedia.org/wiki/Nextcloud

:::note Nextcloud is a suite of client-server software for creating and using file hosting services. Nextcloud is free and open-source, which means that anyone is allowed to install and operate it on their own private server devices. :::

:::warning This setup only works, when NextCloud is running with HTTPS enabled. See here on how to configure this. :::

:::warning In case something goes wrong with the configuration, you can use the URL http://nextcloud.company/login?direct=1 to log in using the built-in authentication. :::

Preparation

The following placeholders will be used:

• nextcloud.company is the FQDN of the NextCloud install.
• authentik.company is the FQDN of the authentik install.

Create an application in authentik and note the slug, as this will be used later. Create a SAML provider with the following parameters:

• ACS URL: https://nextcloud.company/apps/user_saml/saml/acs
• Issuer: https://authentik.company
• Service Provider Binding: Post
• Audience: https://nextcloud.company/apps/user_saml/saml/metadata
• Signing Keypair: Select any certificate you have.
• Property mappings: Select all Managed mappings.

You can of course use a custom signing certificate, and adjust durations.

NextCloud

In NextCloud, ensure that the SSO & SAML Authentication extension is installed. Navigate to Settings, then SSO & SAML Authentication.

Set the following values:

• Attribute to map the UID to.: http://schemas.goauthentik.io/2021/02/saml/username
• Optional display name of the identity provider (default: "SSO & SAML log in"): authentik
• Identifier of the IdP entity (must be a URI): https://authentik.company
• URL Target of the IdP where the SP will send the Authentication Request Message: https://authentik.company/application/saml/<application-slug>/sso/binding/redirect/
• Public X.509 certificate of the IdP: Copy the PEM of the Selected Signing Certificate

Under Attribute mapping, set these values:

• Attribute to map the displayname to.: http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name
• Attribute to map the email address to.: http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress
• Attribute to map the users groups to.: http://schemas.xmlsoap.org/claims/Group

Group Quotas

Create a group for each different level of quota you want users to have. Set a custom attribute, for example called nextcloud_quota, to the quota you want, for example 15 GB.

Afterwards, create a custom SAML Property Mapping with the name SAML NextCloud Quota. Set the SAML Name to nextcloud_quota. Set the Expression to return user.group_attributes.get("nextcloud_quota", "1 GB"), where 1 GB is the default value for users that don't belong to another group (or have another value set).

Admin Group

To give authentik users admin access to your NextCloud instance, you need to create a custom Property Mapping that maps an authentik group to "admin". It has to be mapped to "admin" as this is static in NextCloud and cannot be changed.

Create a SAML Property mapping with the SAML Name "http://schemas.xmlsoap.org/claims/Group" and this expression:

for group in user.ak_groups.all():
    yield group.name
if ak_is_group_member(request.user, name="<authentik nextcloud admin group's name>"):
    yield "admin"

Then, edit the NextCloud SAML Provider, and replace the default Groups mapping with the one you've created above.