Integrate with Hashicorp Vault

What is Vault

Secure, store and tightly control access to tokens, passwords, certificates, encryption keys for protecting secrets and other sensitive data using a UI, CLI, or HTTP API.

-- https://vaultproject.io

:::info This is based on authentik 2022.2.1 and Vault 1.9.3. Instructions may differ between versions. This guide does not cover vault policies. See https://learn.hashicorp.com/tutorials/vault/oidc-auth?in=vault/auth-methods for a more in-depth vault guide :::

Preparation

The following placeholders are used in this guide:

• authentik.company is the FQDN of the authentik installation.
• vault.company is the FQDN of the Vault installation.

:::info This documentation lists only the settings that you need to change from their default values. Be aware that any changes other than those explicitly mentioned in this guide could cause issues accessing your application. :::

authentik configuration

To support the integration of Hashicorp Vault with authentik, you need to create an application/provider pair in authentik.

Create an application and provider in authentik

1. Log in to authentik as an administrator and open the authentik Admin interface.
2. Navigate to Applications > Applications and click Create with Provider to create an application and provider pair. (Alternatively you can first create a provider separately, then create the application and connect it with the provider.)

• Application: provide a descriptive name, an optional group for the type of application, the policy engine mode, and optional UI settings.
• Choose a Provider type: select OAuth2/OpenID Connect as the provider type.
• Configure the Provider: provide a name (or accept the auto-provided name), the authorization flow to use for this provider, and the following required configurations.
  • Note the Client ID, Client Secret, and slug values because they will be required later.
  • Add three Strict redirect URIs and set them to https://vault.company/ui/vault/auth/oidc/oidc/callback, https://vault.company/oidc/callback, and http://localhost:8250/oidc/callback.
  • Select any available signing key.
• Configure Bindings (optional): you can create a binding (policy, group, or user) to manage the listing and access to applications on a user's My applications page.

3. Click Submit to save the new application and provider.

Hashicorp Vault configuration

Enable the oidc auth method vault auth enable oidc

Configure the oidc auth method, oidc discovery url is the OpenID Configuration Issuer in your provider

vault write auth/oidc/config \
         oidc_discovery_url="https://authentik.company/application/o/<application_slug>/" \
         oidc_client_id="Client ID" \
         oidc_client_secret="Client Secret" \
         default_role="reader"

Create the reader role

vault write auth/oidc/role/reader \
      bound_audiences="Client ID" \
      allowed_redirect_uris="https://vault.company/ui/vault/auth/oidc/oidc/callback" \
      allowed_redirect_uris="https://vault.company/oidc/callback" \
      allowed_redirect_uris="http://localhost:8250/oidc/callback" \
      user_claim="sub" \
      policies="reader"

External Groups

If you wish to manage group membership in Hashicorp Vault via Authentik you have to use external groups.

:::info This assumes that the steps above have already been completed and tested. :::

Step 1

In authentik, edit the OIDC provider created above. Under Advanced protocol settings add authentik default OAuth Mapping: OpenID 'profile' This includes the groups mapping.

Step 2

In Vault, change the reader role to have the following settings:

vault write auth/oidc/role/reader \
      bound_audiences="Client ID" \
      allowed_redirect_uris="https://vault.company/ui/vault/auth/oidc/oidc/callback" \
      allowed_redirect_uris="https://vault.company/oidc/callback" \
      allowed_redirect_uris="http://localhost:8250/oidc/callback" \
      user_claim="sub" \
      policies="reader" \
      groups_claim="groups" \
      oidc_scopes="openid,profile,email"

Add a group.

vault write identity/group \
    name="reader" \
    policies="reader" \
    type="external"

Get the canonical ID of the group.

vault list identity/group/id

Get the ID of the OIDC accessor.

vault auth list

Add a group alias, this maps the group to the OIDC backend.

vault write identity/group-alias \
    mount_accessor="auth_oidc_xxxxxx" \
    canonical_id="group_id" \
    name="group name in authentik"

You should then be able to sign in via OIDC. vault login -method=oidc role="reader"