# Source: https://infisical.com/docs/documentation/platform/identities/kubernetes-auth.md

> ## Documentation Index
> Fetch the complete documentation index at: https://infisical.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Kubernetes Auth

> Learn how to authenticate with Infisical in Kubernetes

**Kubernetes Auth** is a Kubernetes-native authentication method for applications (e.g. pods) to access Infisical.

## Diagram

The following sequence diagram illustrates the Kubernetes Auth workflow for authenticating applications running in pods with Infisical.

```mermaid  theme={"dark"}
sequenceDiagram
  participant Pod as Pod
  participant Infis as Infisical
  participant KubernetesServer as K8s API Server

  Note over Pod: Step 1: Service Account JWT Token Retrieval

  Note over Pod,Infis: Step 2: JWT Token Login Operation
  Pod->>Infis: Send JWT token to /api/v1/auth/kubernetes-auth/login
  Infis->>KubernetesServer: Forward JWT token for validation
    KubernetesServer-->>Infis: Return identity info for JWT

  Note over Infis: Step 3: Identity Property Verification
  Infis->>Pod: Return short-lived access token

  Note over Pod,Infis: Step 4: Access Infisical API with Token
  Pod->>Infis: Make authenticated requests using the short-lived access token
```

## Concept

At a high-level, Infisical authenticates an application in Kubernetes by verifying its identity and checking that it meets specific requirements (e.g. it is bound to an allowed service account) at the `/api/v1/auth/kubernetes-auth/login` endpoint. If successful,
then Infisical returns a short-lived access token that can be used to make authenticated requests to the Infisical API.

To be more specific:

1. The application deployed on Kubernetes retrieves its [service account credential](https://kubernetes.io/docs/tasks/configure-pod-container/configure-service-account/#opt-out-of-api-credential-automounting) that is a JWT token at the `/var/run/secrets/kubernetes.io/serviceaccount/token` pod path.
2. The application sends the JWT token to Infisical at the `/api/v1/auth/kubernetes-auth/login` endpoint after which Infisical forwards the JWT token to the Kubernetes API Server at the TokenReview API for verification and to obtain the service account information associated with the JWT token.
   Infisical is able to authenticate and interact with the TokenReview API by using either the long lived JWT token set while configuring this authentication method or by using the incoming token itself. The JWT token mentioned in this context is referred as the token reviewer JWT token.
3. Infisical checks the service account properties against set criteria such **Allowed Service Account Names** and **Allowed Namespaces**.
4. If all is well, Infisical returns a short-lived access token that the application can use to make authenticated requests to the Infisical API.

<Note>
  We recommend using one of Infisical's clients like SDKs or the Infisical Agent
  to authenticate with Infisical using Kubernetes Auth as they handle the
  authentication process including service account credential retrieval for you.
</Note>

## Guide

In the following steps, we explore how to create and use identities for your applications in Kubernetes to access the Infisical API using the Kubernetes Auth authentication method.

<Steps>
  <Step title="Obtaining the token reviewer JWT for Infisical">
    <Accordion title="Option 1: Reviewer JWT Token">
      <Note>
        **When to use this option**: Choose this approach when you want centralized authentication management. Only one service account needs special permissions, and your application service accounts remain unchanged.
      </Note>

      1.1. Start by creating a service account in your Kubernetes cluster that will be used by Infisical to authenticate with the Kubernetes API Server.

      ```yaml infisical-service-account.yaml theme={"dark"}
      apiVersion: v1
      kind: ServiceAccount
      metadata:
        name: infisical-auth
        namespace: default
      ```

      ```
      kubectl apply -f infisical-service-account.yaml
      ```

      1.2. Bind the service account to the `system:auth-delegator` cluster role. As described [here](https://kubernetes.io/docs/reference/access-authn-authz/rbac/#other-component-roles), this role allows delegated authentication and authorization checks, specifically for Infisical to access the [TokenReview API](https://kubernetes.io/docs/reference/kubernetes-api/authentication-resources/token-review-v1/). You can apply the following configuration file:

      ```yaml cluster-role-binding.yaml theme={"dark"}
      apiVersion: rbac.authorization.k8s.io/v1
      kind: ClusterRoleBinding
      metadata:
        name: role-tokenreview-binding
        namespace: default
      roleRef:
        apiGroup: rbac.authorization.k8s.io
        kind: ClusterRole
        name: system:auth-delegator
      subjects:
        - kind: ServiceAccount
          name: infisical-auth
          namespace: default
      ```

      ```
      kubectl apply -f cluster-role-binding.yaml
      ```

      1.3. Next, create a long-lived service account JWT token (i.e. the token reviewer JWT token) for the service account using this configuration file for a new `Secret` resource:

      ```yaml service-account-token.yaml theme={"dark"}
      apiVersion: v1
      kind: Secret
      type: kubernetes.io/service-account-token
      metadata:
        name: infisical-auth-token
        annotations:
          kubernetes.io/service-account.name: "infisical-auth"
      ```

      ```
      kubectl apply -f service-account-token.yaml
      ```

      1.4. Link the secret in step 1.3 to the service account in step 1.1:

      ```bash  theme={"dark"}
      kubectl patch serviceaccount infisical-auth -p '{"secrets": [{"name": "infisical-auth-token"}]}' -n default
      ```

      1.5. Finally, retrieve the token reviewer JWT token from the secret.

      ```bash  theme={"dark"}
      kubectl get secret infisical-auth-token -n default -o=jsonpath='{.data.token}' | base64 --decode
      ```

      Keep this JWT token handy as you will need it for the **Token Reviewer JWT** field when configuring the Kubernetes Auth authentication method for the identity in step 2.
    </Accordion>

    <Accordion title="Option 2: Client JWT as Reviewer JWT Token">
      <Note>
        **When to use this option**: Choose this approach to eliminate long-lived tokens. This option simplifies Infisical configuration but requires each application service account to have elevated permissions.
      </Note>

      The self-validation method eliminates the need for a separate long-lived reviewer JWT by using the same token for both authentication and validation. Instead of creating a dedicated reviewer service account, you'll grant the necessary permissions to each application service account.

      For each service account that needs to authenticate with Infisical, add the `system:auth-delegator` role:

      ```yaml client-role-binding.yaml theme={"dark"}
      apiVersion: rbac.authorization.k8s.io/v1
      kind: ClusterRoleBinding
      metadata:
        name: infisical-client-binding-[your-app-name]
      roleRef:
        apiGroup: rbac.authorization.k8s.io
        kind: ClusterRole
        name: system:auth-delegator
      subjects:
        - kind: ServiceAccount
          name: [your-app-service-account]
          namespace: [your-app-namespace]
      ```

      ```
      kubectl apply -f client-role-binding.yaml
      ```

      When configuring Kubernetes Auth in Infisical, leave the **Token Reviewer JWT** field empty. Infisical will use the client's own token for validation.
    </Accordion>

    <Accordion title="Option 3: Use Gateway as Reviewer">
      <Note>
        **When to use this option**: Choose this approach when you have a gateway deployed in your Kubernetes Cluster and wish to eliminate long-lived tokens. This approach simplifies Infisical Kubernetes Auth configuration, and only one service account will need to have the elevated `system:auth-delegator` ClusterRole binding.
      </Note>

      <Info>
        **Note:** Gateway is a paid feature. - **Infisical Cloud users:** Gateway is
        available under the **Enterprise Tier**. - **Self-Hosted Infisical:** Please
        contact [sales@infisical.com](mailto:sales@infisical.com) to purchase an
        enterprise license.
      </Info>

      <Steps>
        <Step title="Deploying a gateway">
          To deploy a gateway in your Kubernetes cluster, follow our [Gateway deployment guide using helm](/documentation/platform/gateways/overview).
        </Step>

        <Step title="Grant the gateway the system:auth-delegator ClusterRole binding">
          To grant the gateway the `system:auth-delegator` ClusterRole binding, you can use the following command:

          ```yaml gateway-role-binding.yaml theme={"dark"}
          apiVersion: rbac.authorization.k8s.io/v1
          kind: ClusterRoleBinding
          metadata:
            name: infisical-token-reviewer-role-binding
            namespace: default # Replace with your namespace if not default
          roleRef:
            apiGroup: rbac.authorization.k8s.io
            kind: ClusterRole
            name: system:auth-delegator
          subjects:
            - kind: ServiceAccount
              name: infisical-gateway # The name of the gateway service account
              namespace: default # Replace with your namespace if not default
          ```

          ```bash  theme={"dark"}
          kubectl apply -f gateway-role-binding.yaml
          ```

          <Tip>
            The gateway service account name is `infisical-gateway` by default if deployed using Helm.
          </Tip>
        </Step>

        <Step title="Configure the Kubernetes Auth authentication method for the identity">
          To configure your Kubernetes Auth method to use the gateway as the token reviewer, set the `Review Method` to "Gateway as Reviewer", and select the gateway you want to use as the token reviewer.

                    <img src="https://mintlify.s3.us-west-1.amazonaws.com/infisical/images/platform/identities/identities-kubernetes-auth-gateway-as-reviewer.png" alt="identities organization create kubernetes auth method" />
        </Step>
      </Steps>
    </Accordion>
  </Step>

  <Step title="Creating an identity">
    To create an identity, head to your Organization Settings > Access Control > Identities and press **Create identity**.

        <img src="https://mintlify.s3.us-west-1.amazonaws.com/infisical/images/platform/identities/identities-org.png" alt="identities organization" />

    When creating an identity, you specify an organization level [role](/documentation/platform/access-controls/role-based-access-controls) for it to assume; you can configure roles in Organization Settings > Access Control > Organization Roles.

        <img src="https://mintlify.s3.us-west-1.amazonaws.com/infisical/images/platform/identities/identities-org-create.png" alt="identities organization create" />

    Now input a few details for your new identity. Here's some guidance for each field:

    * Name (required): A friendly name for the identity.
    * Role (required): A role from the **Organization Roles** tab for the identity to assume. The organization role assigned will determine what organization level resources this identity can have access to.

    Once you've created an identity, you'll be redirected to a page where you can manage the identity.

        <img src="https://mintlify.s3.us-west-1.amazonaws.com/infisical/images/platform/identities/identities-page.png" alt="identities page" />

    Since the identity has been configured with Universal Auth by default, you should re-configure it to use Kubernetes Auth instead. To do this, press to edit the **Authentication** section,
    remove the existing Universal Auth configuration, and add a new Kubernetes Auth configuration onto the identity.

        <img src="https://mintlify.s3.us-west-1.amazonaws.com/infisical/images/platform/identities/identities-page-remove-default-auth.png" alt="identities page remove default auth" />

        <img src="https://mintlify.s3.us-west-1.amazonaws.com/infisical/images/platform/identities/identities-org-create-kubernetes-auth-method.png" alt="identities organization create kubernetes auth method" />

    Here's some more guidance on each field:

    * Kubernetes Host / Base Kubernetes API URL: The host string, host:port pair, or URL to the base of the Kubernetes API server. This can usually be obtained by running `kubectl cluster-info`.
    * Token Reviewer JWT: A long-lived service account JWT token for Infisical to access the [TokenReview API](https://kubernetes.io/docs/reference/kubernetes-api/authentication-resources/token-review-v1/) to validate other service account JWT tokens submitted by applications/pods. This is the JWT token obtained from step 1.5(Reviewer Tab). If omitted, the client's own JWT will be used instead, which requires the client to have the `system:auth-delegator` ClusterRole binding.
      This is shown in step 1, option 2.
    * Allowed Service Account Names: A comma-separated list of trusted service account names that are allowed to authenticate with Infisical.
    * Allowed Namespaces: A comma-separated list of trusted namespaces that service accounts must belong to authenticate with Infisical.
    * Allowed Audience: An optional audience claim that the service account JWT token must have to authenticate with Infisical.
    * CA Certificate: The PEM-encoded CA cert for the Kubernetes API server. This is used by the TLS client for secure communication with the Kubernetes API server.
    * Access Token TTL (default is `2592000` equivalent to 30 days): The lifetime for an acccess token in seconds. This value will be referenced at renewal time.
    * Access Token Max TTL (default is `2592000`  equivalent to 30 days): The maximum lifetime for an acccess token in seconds. This value will be referenced at renewal time.
    * Access Token Max Number of Uses (default is `0`): The maximum number of times that an access token can be used; a value of `0` implies infinite number of uses.
    * Access Token Trusted IPs: The IPs or CIDR ranges that access tokens can be used from. By default, each token is given the `0.0.0.0/0`, allowing usage from any network address.
  </Step>

  <Step title="Adding an identity to a project">
    To enable the identity to access project-level resources such as secrets within a specific project, you should add it to that project.

    To do this, head over to the project you want to add the identity to and go to Project Settings > Access Control > Machine Identities and press **Add identity**.

    Next, select the identity you want to add to the project and the project level role you want to allow it to assume. The project role assigned will determine what project level resources this identity can have access to.

        <img src="https://mintlify.s3.us-west-1.amazonaws.com/infisical/images/platform/identities/identities-project.png" alt="identities project" />

        <img src="https://mintlify.s3.us-west-1.amazonaws.com/infisical/images/platform/identities/identities-project-create.png" alt="identities project create" />
  </Step>

  <Step title="Accessing the Infisical API with the identity">
    To access the Infisical API as the identity, you should first make sure that the pod running your application is bound to a service account specified in the **Allowed Service Account Names** field of the identity's Kubernetes Auth authentication method configuration in step 2.

    Once bound, the pod will receive automatically mounted service account credentials that is a JWT token at the `/var/run/secrets/kubernetes.io/serviceaccount/token` path. This token should be used to authenticate with Infisical at the `/api/v1/auth/kubernetes-auth/login` endpoint.

    For information on how to configure sevice accounts for pods, refer to the guide [here](https://kubernetes.io/docs/tasks/configure-pod-container/configure-service-account/).

    We provide a code example below of how you might retrieve the JWT token and use it to authenticate with Infisical to gain access to the [Infisical API](/api-reference/overview/introduction).

    <Accordion title="Sample code for inside an application">
      The shown example uses Node.js but you can use any other language to retrieve the service account JWT token and use it to authenticate with Infisical.

      ```javascript  theme={"dark"}
      const fs = require("fs");
      try {
          const tokenPath = "/var/run/secrets/kubernetes.io/serviceaccount/token";
          const jwtToken = fs.readFileSync(tokenPath, "utf8");

          const infisicalUrl = "https://app.infisical.com"; // or your self-hosted Infisical URL
          const identityId = "<your-identity-id>";

          const { data } = await axios.post(
              `{infisicalUrl}/api/v1/auth/kubernetes-auth/login`,
              {
                  identityId,
                  jwt,
              }
          );

          console.log("result data: ", data); // access token here
      } catch(err) {
          console.error(err);
      }
      ```
    </Accordion>

    <Tip>
      We recommend using one of Infisical's clients like SDKs or the Infisical Agent to authenticate with Infisical using Kubernetes Auth as they handle the authentication process including service account credential retrieval for you.
    </Tip>

    <Note>
      Each identity access token has a time-to-live (TTL) which you can infer from the response of the login operation;
      the default TTL is `7200` seconds which can be adjusted.

      If an identity access token exceeds its max ttl, it can no longer authenticate with the Infisical API. In this case,
      a new access token should be obtained by performing another login operation.
    </Note>
  </Step>
</Steps>

**FAQ**

<AccordionGroup>
  <Accordion title="Why is the Infisical API rejecting my service account JWT token?">
    There are a few reasons for why this might happen:

    * The Kubernetes Auth authentication method configuration is invalid.
    * The service account JWT token has expired is malformed or invalid.
    * The service account associated with the JWT token does not meet the criteria set forth in the Kubernetes Auth authentication method configuration such as **Allowed Service Account Names** and **Allowed Namespaces**.
  </Accordion>

  <Accordion title="Why is the Infisical API rejecting my access token?">
    There are a few reasons for why this might happen:

    * The access token has expired.
    * The identity is insufficiently permissioned to interact with the resources you wish to access.
    * The client access token is being used from an untrusted IP.
  </Accordion>

  <Accordion title="What is access token renewal and TTL/Max TTL?">
    A identity access token can have a time-to-live (TTL) or incremental lifetime after which it expires.

    In certain cases, you may want to extend the lifespan of an access token; to do so, you must set a max TTL parameter.

    A token can be renewed any number of times where each call to renew it can extend the token's lifetime by increments of the access token's TTL.
    Regardless of how frequently an access token is renewed, its lifespan remains bound to the maximum TTL determined at its creation.
  </Accordion>
</AccordionGroup>