OpenShell/docs/kubernetes/access-control.mdx

---
# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0
title: "Access Control"
sidebar-title: "Access Control"
description: "Configure OIDC user authentication or reverse-proxy auth termination for a Kubernetes-deployed OpenShell gateway."
keywords: "Generative AI, Cybersecurity, Kubernetes, Authentication, mTLS, OIDC, Keycloak, Entra ID, Okta, Gateway Auth"
position: 5
---

The OpenShell gateway supports two access-control models for human callers on Kubernetes:

| Model | When to use |
|---|---|
| OIDC (recommended) | Production deployments. Integrates with an existing identity provider, supports role-based access control, and gives each user their own identity without distributing certificates. |
| Reverse-proxy auth termination | An access proxy (Cloudflare Access, ngrok, corporate SSO) authenticates callers in front of the gateway. The gateway trusts the proxy and skips its own client-cert check. |

The Helm chart always generates mTLS certificates at install time. The gateway uses them for transport-layer security regardless of which access-control model you choose. The client bundle in the `openshell-client-tls` secret is used internally by sandbox supervisors, not for granting access to individual users.

For how the CLI resolves gateways and stores credentials, refer to [Gateway Authentication](/reference/gateway-auth).

## Sandbox Supervisor Identity

Kubernetes sandbox supervisors authenticate back to the gateway as sandbox workloads. By default, the gateway mints its own sandbox JWTs and Kubernetes sandboxes bootstrap them with a projected ServiceAccount token.

Dynamic provider token grants can use SPIFFE without changing supervisor-to-gateway authentication. Set `server.providerTokenGrants.spiffe.enabled=true` to mount the SPIFFE CSI Workload API socket into sandbox pods while keeping the projected ServiceAccount token bootstrap and gateway-minted sandbox JWT path.

Provider token grants require a SPIFFE implementation such as SPIRE and a `ClusterSPIFFEID` that assigns per-sandbox IDs from the pod's `openshell.io/sandbox-id` annotation. Provider profiles with `token_grant` metadata cause the sandbox supervisor to request JWT-SVIDs and exchange them for upstream OAuth2 access tokens.

## OIDC User Authentication

Set `server.oidc.issuer` to enable OIDC. The gateway validates the `Authorization: Bearer <token>` header on every request against the issuer's JWKS endpoint.

```shell
helm upgrade openshell \
  oci://ghcr.io/nvidia/openshell/helm-chart \
  --version <version> \
  --namespace openshell \
  --set server.oidc.issuer=https://your-idp.example.com/realms/openshell \
  --set server.oidc.audience=openshell-cli
```

The `audience` value must match the client ID configured in your identity provider for the OpenShell resource server.

### OIDC values reference

| Value | Default | Purpose |
|---|---|---|
| `server.oidc.issuer` | `""` | OIDC issuer URL. Empty disables OIDC. |
| `server.oidc.audience` | `openshell-cli` | Expected `aud` claim in the JWT. |
| `server.oidc.jwksTtl` | `3600` | JWKS key cache TTL in seconds. |
| `server.oidc.rolesClaim` | `""` | Dot-separated path to the roles array in JWT claims. |
| `server.oidc.adminRole` | `""` | Role name that grants admin access. |
| `server.oidc.userRole` | `""` | Role name that grants standard user access. |
| `server.oidc.scopesClaim` | `""` | Dot-separated path to the scopes array in JWT claims. |

### Auth-only mode vs. RBAC mode

Leave both `adminRole` and `userRole` empty to use auth-only mode: any request with a valid JWT from the configured issuer is accepted, but no role distinction is enforced.

Set both values to enable RBAC mode, where the gateway checks the role claim and enforces access based on the assigned role:

```shell
helm upgrade openshell \
  oci://ghcr.io/nvidia/openshell/helm-chart \
  --version <version> \
  --namespace openshell \
  --set server.oidc.issuer=https://your-idp.example.com/realms/openshell \
  --set server.oidc.audience=openshell-cli \
  --set server.oidc.rolesClaim=realm_access.roles \
  --set server.oidc.adminRole=openshell-admin \
  --set server.oidc.userRole=openshell-user
```

Both `adminRole` and `userRole` must be set, or both must be empty. Setting only one is not supported.

### Provider-specific rolesClaim paths

| Provider | rolesClaim value |
|---|---|
| Keycloak | `realm_access.roles` |
| Microsoft Entra ID | `roles` |
| Okta | `groups` |

## Reverse-Proxy Auth Termination

When an access proxy, such as Cloudflare Access, ngrok, or a corporate SSO gateway, handles authentication in front of the OpenShell gateway, you can explicitly allow unauthenticated user calls at the gateway:

```shell
helm upgrade openshell \
  oci://ghcr.io/nvidia/openshell/helm-chart \
  --version <version> \
  --namespace openshell \
  --set server.auth.allowUnauthenticatedUsers=true
```

The gateway still serves TLS and sandbox supervisors still authenticate with gateway-minted sandbox JWTs. User-facing CLI/API calls without OIDC or mTLS credentials are accepted as an unauthenticated local developer principal. The proxy is responsible for authenticating callers and forwarding only authorized traffic.

To also disable TLS entirely (when the proxy terminates TLS before the request reaches the gateway):

```shell
  --set server.disableTls=true \
  --set server.auth.allowUnauthenticatedUsers=true
```

<Warning>
Only enable unauthenticated users when the gateway is not reachable from outside a trusted local development environment or the proxy path is fully trusted. Never expose a plaintext, auth-disabled gateway to a public network.
</Warning>

Register the gateway with the CLI using the proxy's public URL. The browser-based login flow runs automatically on first use:

```shell
openshell gateway add https://gateway.example.com --name production
```