»Azure Auth Method

The azure auth method allows authentication against Vault using Azure Active Directory credentials. It treats Azure as a Trusted Third Party and expects a JSON Web Token (JWT) signed by Azure Active Directory for the configured tenant.

This method supports authentication for system-assigned and user-assigned managed identities. See Azure Managed Service Identity (MSI) for more information about these resources.

»Prerequisites:

The following documentation assumes that the method has been mounted at auth/azure.

A configured Azure AD application which is used as the resource for generating MSI access tokens.
Client credentials (shared secret) for accessing the Azure Resource Manager with read access to compute endpoints. See Azure AD Service to Service Client Credentials

Required Azure API permissions to be granted to Vault user:

Microsoft.Compute/virtualMachines/*/read
Microsoft.Compute/virtualMachineScaleSets/*/read

NOTE: The above permissions are only required when the associated vm* parameters are used on login. Please see the API doc for more details.

If Vault is hosted on Azure, Vault can use MSI to access Azure instead of a shared secret. MSI must be enabled on the VMs hosting Vault.

The next sections review how the authN/Z workflows work. If you have already reviewed these sections, here are some quick links to:

Usage
API documentation docs.

»Authentication

»Via the CLI

The default path is /auth/azure. If this auth method was enabled at a different path, specify auth/my-path/login instead.

$ vault write auth/azure/login \
    role="dev-role" \
    jwt="eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..." \
    subscription_id="12345-..." \
    resource_group_name="test-group" \
    vm_name="test-vm"

The role and jwt parameters are required. When using bound_service_principal_ids and bound_group_ids in the token roles, all the information is required in the JWT (except for vm_name and vmss_name). When using other bound_* parameters, calls to Azure APIs will be made and subscription id, resource group name, and vm name/vmss_name are all required and can be obtained through instance metadata.

For example:

$ vault write auth/azure/login role="dev-role" \
     jwt="$(curl -s 'http://169.254.169.254/metadata/identity/oauth2/token?api-version=2018-02-01&resource=https%3A%2F%2Fvault.hashicorp.com%2F' -H Metadata:true | jq -r '.access_token')" \
     subscription_id=$(curl -s -H Metadata:true "http://169.254.169.254/metadata/instance?api-version=2017-08-01" | jq -r '.compute | .subscriptionId')  \
     resource_group_name=$(curl -s -H Metadata:true "http://169.254.169.254/metadata/instance?api-version=2017-08-01" | jq -r '.compute | .resourceGroupName') \
     vm_name=$(curl -s -H Metadata:true "http://169.254.169.254/metadata/instance?api-version=2017-08-01" | jq -r '.compute | .name')

»Via the API

The default endpoint is auth/azure/login. If this auth method was enabled at a different path, use that value instead of azure.

$ curl \
    --request POST \
    --data '{"role": "dev-role", "jwt": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."}' \
    https://127.0.0.1:8200/v1/auth/azure/login

The response will contain the token at auth.client_token:

{
  "auth": {
    "client_token": "f33f8c72-924e-11f8-cb43-ac59d697597c",
    "accessor": "0e9e354a-520f-df04-6867-ee81cae3d42d",
    "policies": ["default", "dev", "prod"],
    "lease_duration": 2764800,
    "renewable": true
  }
}

»Configuration

Auth methods must be configured in advance before machines can authenticate. These steps are usually completed by an operator or configuration management tool.

»Via the CLI

Enable Azure authentication in Vault:
```
$ vault auth enable azure
```

Configure the Azure auth method:

$ vault write auth/azure/config \
    tenant_id=7cd1f227-ca67-4fc6-a1a4-9888ea7f388c \
    resource=https://vault.hashicorp.com \
    client_id=dd794de4-4c6c-40b3-a930-d84cd32e9699 \
    client_secret=IT3B2XfZvWnfB98s1cie8EMe7zWg483Xy8zY004=

For the complete list of configuration options, please see the API documentation.

Create a role:
```
$ vault write auth/azure/role/dev-role \
    policies="prod,dev" \
    bound_subscription_ids=6a1d5988-5917-4221-b224-904cd7e24a25 \
    bound_resource_groups=vault
```
Roles are associated with an authentication type/entity and a set of Vault policies. Roles are configured with constraints specific to the authentication type, as well as overall constraints and configuration for the generated auth tokens.
For the complete list of role options, please see the API documentation.

»Via the API

Enable Azure authentication in Vault:

$ curl \
    --header "X-Vault-Token: ..." \
    --request POST \
    --data '{"type": "azure"}' \
    https://127.0.0.1:8200/v1/sys/auth/azure

Configure the Azure auth method:

$ curl \
    --header "X-Vault-Token: ..." \
    --request POST \
    --data '{"tenant_id": "...", "resource": "..."}' \
    https://127.0.0.1:8200/v1/auth/azure/config

Create a role:

$ curl \
    --header "X-Vault-Token: ..." \
    --request POST \
    --data '{"policies": ["dev", "prod"], ...}' \
    https://127.0.0.1:8200/v1/auth/azure/role/dev-role

»Plugin Setup

The following section is only relevant if you decide to enable the azure auth method as an external plugin. The azure plugin method is integrated into Vault as a builtin method by default.

Assuming you have saved the binary vault-plugin-auth-azure to some folder and configured the plugin directory for your server at path/to/plugins:

Enable the plugin in the catalog:

$ vault write sys/plugins/catalog/auth/azure-auth \
    command="vault-plugin-auth-azure" \
    sha256="..."

Enable the azure auth method as a plugin:

$ vault auth enable -path=azure azure-auth

»API

The Azure Auth Plugin has a full HTTP API. Please see the API documentation for more details.