Files
OpenShell/docs/reference/gateway-config.mdx
Dimitar Mirchev 9a1e04c591 docs: document per-driver compute-driver features
- README.md gains a "Choosing Which Compute Drivers Are Compiled In"
  section covering the four driver features, the extension-only
  build shape, and the startup-time compiled-out rejection.
- architecture/compute-runtimes.md gains a "Compile-Time Driver
  Selection" section covering the four driver features, the
  extension-only zero-driver build, the startup-time missing-driver
  error, filtered auto-detection, and the always-available extension
  driver path.
- docs/reference/gateway-config.mdx gains a matching reference
  section under "Choosing Which Drivers Are Compiled In" with a
  per-feature table, single-driver / mixed / extension-only build
  examples, and the startup-time rejection contract.

Signed-off-by: Dimitar Mirchev <28221091+dimityrmirchev@users.noreply.github.com>
2026-07-07 15:07:38 +03:00

387 lines
17 KiB
Plaintext

---
# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0
title: "Gateway Configuration File"
sidebar-title: "Gateway Config"
description: "Reference for the OpenShell gateway TOML configuration file (RFC 0003)."
keywords: "Generative AI, Cybersecurity, AI Agents, Sandboxing, Gateway, Configuration, TOML, Reference"
position: 5
---
The OpenShell gateway reads its configuration from a TOML file when `--config` or `OPENSHELL_GATEWAY_CONFIG` is set. When neither is set, the gateway reads `$XDG_CONFIG_HOME/openshell/gateway.toml` if that file exists. If no config file exists, the gateway starts from built-in defaults. Gateway process flags and gateway `OPENSHELL_*` environment variables override the file. Compute driver settings live in the driver TOML tables. See [RFC 0003](https://github.com/NVIDIA/OpenShell/blob/main/rfc/0003-gateway-configuration/README.md) for the full schema.
## Source Precedence
```text
Gateway CLI flag > gateway OPENSHELL_* env var > TOML file > built-in default
```
`database_url` is env-only. The loader rejects it when it appears in the file. When `OPENSHELL_DB_URL` is unset, the gateway stores its SQLite database under `$XDG_STATE_HOME/openshell/gateway/openshell.db`.
## Package-Managed Locations
Package-managed gateways do not require a TOML file. Create one at the package's optional config location when you need to override built-in defaults. Set `OPENSHELL_GATEWAY_CONFIG` in the launch environment to use a different file.
| Package | Optional Gateway TOML location |
|---|---|
| Homebrew | `$XDG_CONFIG_HOME/openshell/gateway.toml` when it exists, otherwise an existing Homebrew prefix config such as `/opt/homebrew/var/openshell/gateway.toml`. |
| Debian/Ubuntu | `$XDG_CONFIG_HOME/openshell/gateway.toml`, usually `~/.config/openshell/gateway.toml` for the systemd user service. |
| Fedora/RHEL RPM | `$XDG_CONFIG_HOME/openshell/gateway.toml`, usually `~/.config/openshell/gateway.toml` for the systemd user service. |
| Snap | `$SNAP_COMMON/gateway.toml`, usually `/var/snap/openshell/common/gateway.toml`. |
## Layout
The file is rooted at `[openshell]`. Gateway-wide settings live under `[openshell.gateway]`. Each compute driver owns its own `[openshell.drivers.<name>]` table. Shared keys set at gateway scope are inherited into driver tables when not overridden.
```toml
[openshell]
version = 1
[openshell.gateway]
# ... gateway-wide settings ...
[openshell.gateway.tls]
# ... gateway listener TLS ...
[openshell.gateway.oidc]
# ... JWT bearer auth ...
[openshell.drivers.kubernetes]
# ... driver-specific settings ...
```
## Full Example
A complete gateway configuration covering every section. Trim to the fields you need.
```toml
# SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0
[openshell]
version = 1
[openshell.gateway]
bind_address = "0.0.0.0:8080"
health_bind_address = "0.0.0.0:8081"
metrics_bind_address = "0.0.0.0:9090"
log_level = "info"
# When empty, the gateway auto-detects Kubernetes, then Podman, then Docker.
# VM is never auto-detected and requires an explicit entry here.
compute_drivers = ["kubernetes"]
sandbox_namespace = "openshell"
ssh_session_ttl_secs = 3600
# Subject Alternative Names baked into the gateway server certificate.
# Wildcard DNS SANs (e.g. "*.dev.openshell.localhost") also enable sandbox
# service URLs under that domain.
server_sans = ["openshell", "*.dev.openshell.localhost"]
# Allow plaintext HTTP routing for loopback sandbox service URLs.
enable_loopback_service_http = true
# Set true only for local plaintext gateways or trusted TLS termination.
disable_tls = false
# Shared driver defaults. These inherit into [openshell.drivers.<name>] tables
# when the driver-specific table does not override them.
default_image = "ghcr.io/nvidia/openshell/sandbox:latest"
supervisor_image = "ghcr.io/nvidia/openshell/supervisor:latest"
client_tls_secret_name = "openshell-client-tls"
service_account_name = "openshell-sandbox"
host_gateway_ip = "10.0.0.1"
enable_user_namespaces = false
sa_token_ttl_secs = 3600
guest_tls_ca = "/etc/openshell/certs/ca.pem"
guest_tls_cert = "/etc/openshell/certs/client.pem"
guest_tls_key = "/etc/openshell/certs/client-key.pem"
# Optional gRPC rate limit. Both values must be positive to enable the limit.
# Set either value to 0, or omit both, to disable rate limiting.
grpc_rate_limit_requests = 120
grpc_rate_limit_window_seconds = 60
# Gateway listener TLS (distinct from the per-driver guest_tls_*).
[openshell.gateway.tls]
cert_path = "/etc/openshell/certs/gateway.pem"
key_path = "/etc/openshell/certs/gateway-key.pem"
client_ca_path = "/etc/openshell/certs/client-ca.pem"
require_client_auth = false
[openshell.gateway.gateway_jwt]
signing_key_path = "/etc/openshell/jwt/signing.pem"
public_key_path = "/etc/openshell/jwt/public.pem"
kid_path = "/etc/openshell/jwt/kid"
gateway_id = "openshell"
# Omit or set to 0 only for local single-player Docker, Podman, or VM gateways.
ttl_secs = 3600
[openshell.gateway.auth]
allow_unauthenticated_users = false
[openshell.gateway.mtls_auth]
enabled = false
[openshell.gateway.oidc]
issuer = "https://idp.example.com/realms/openshell"
audience = "openshell-cli"
jwks_ttl_secs = 3600
roles_claim = "realm_access.roles"
admin_role = "openshell-admin"
user_role = "openshell-user"
scopes_claim = ""
```
Local Docker, Podman, and VM gateways can also set `[openshell.gateway.mtls_auth] enabled = true` to authenticate CLI callers from verified client certificates. Kubernetes deployments must leave this unset and use OIDC or a trusted access proxy; the Helm chart does not render this table.
`[openshell.gateway.gateway_jwt] ttl_secs` controls gateway-minted sandbox JWT lifetime. When omitted, it defaults to `0`: the token `exp` claim and `expires_at_ms` response field become `0`, and the sandbox JWT does not expire. Use that default only for local single-player Docker, Podman, or VM gateways. Kubernetes and other shared deployments should set a positive TTL; Helm renders `3600` seconds by default, and the gateway logs a warning when a Kubernetes gateway uses `0`.
`[openshell.gateway.auth] allow_unauthenticated_users = true` is an unsafe local-development and trusted-proxy escape hatch. It accepts user-facing CLI/API calls without OIDC or mTLS credentials while sandbox supervisors still authenticate with gateway-minted sandbox JWTs. Leave it false for shared and production gateways.
`image_pull_policy` is intentionally not a shared gateway key. Kubernetes and Docker use `Always`, `IfNotPresent`, or `Never`. Podman uses `always`, `missing`, `never`, or `newer`. Set it inside the relevant driver table.
## Driver References
Each example is a complete TOML file for one compute driver. The examples repeat `[openshell]` and `[openshell.gateway]` so they stay copyable, and the driver tables list the accepted driver-specific keys. Driver-specific values override inherited gateway defaults. The gateway rejects unknown driver fields after inheritance is merged.
### Kubernetes
The gateway runs as a Pod and creates sandbox Pods in another namespace. mTLS material for sandboxes is delivered through a Kubernetes Secret rather than host-side file paths.
```toml
[openshell]
version = 1
[openshell.gateway]
bind_address = "0.0.0.0:8080"
health_bind_address = "0.0.0.0:8081"
metrics_bind_address = "0.0.0.0:9090"
log_level = "info"
compute_drivers = ["kubernetes"]
[openshell.gateway.tls]
cert_path = "/etc/openshell-tls/server/tls.crt"
key_path = "/etc/openshell-tls/server/tls.key"
client_ca_path = "/etc/openshell-tls/client-ca/ca.crt"
[openshell.drivers.kubernetes]
namespace = "agents"
service_account_name = "openshell-sandbox"
default_image = "ghcr.io/nvidia/openshell/sandbox:latest"
image_pull_policy = "IfNotPresent"
image_pull_secrets = ["regcred"]
supervisor_image = "ghcr.io/nvidia/openshell/supervisor:latest"
supervisor_image_pull_policy = "IfNotPresent"
# Use the image volume on Kubernetes >= 1.35 (GA in 1.36); switch to "init-container"
# on older clusters or where the ImageVolume feature gate is off.
supervisor_sideload_method = "image-volume"
# "combined" runs networking and process supervision in the sandbox agent
# container and preserves the existing Kubernetes sandbox behavior.
supervisor_topology = "combined"
grpc_endpoint = "https://openshell-gateway.agents.svc:8080"
ssh_socket_path = "/run/openshell/ssh.sock"
client_tls_secret_name = "openshell-client-tls"
host_gateway_ip = "10.0.0.1"
enable_user_namespaces = false
app_armor_profile = "Unconfined"
workspace_default_storage_size = "10Gi"
# Kubernetes RuntimeClass applied to sandbox pods when the API request does
# not specify one. Empty (default) = omit the field, using the cluster default.
# default_runtime_class_name = "kata-containers"
# Kubelet clamps projected tokens below 600 seconds. The driver caps values at 86400.
sa_token_ttl_secs = 3600
# Optional SPIFFE Workload API socket mounted into sandbox pods for dynamic
# provider token grants. Use an absolute path under a dedicated directory;
# shared roots such as /run, /var, /tmp, and /etc are rejected.
# Supervisor-to-gateway auth still uses gateway JWTs.
provider_spiffe_workload_api_socket_path = "/spiffe-workload-api/spire-agent.sock"
# Explicit sandbox UID/GID for the supervisor container securityContext and
# PVC init container. When unset, the driver auto-detects from OpenShift SCC
# namespace annotations (openshift.io/sa.scc.uid-range) if present, falling
# back to 1000 on non-OpenShift clusters.
# sandbox_uid = 1500
# sandbox_gid = 1500
```
### Docker
Sandboxes run as containers on a local bridge network. The supervisor binary is bind-mounted from the host (no in-cluster image pull required); guest mTLS material is supplied as host paths.
```toml
[openshell]
version = 1
[openshell.gateway]
bind_address = "127.0.0.1:17670"
log_level = "info"
compute_drivers = ["docker"]
[openshell.drivers.docker]
default_image = "ghcr.io/nvidia/openshell/sandbox:latest"
# Docker vocabulary: Always | IfNotPresent | Never. Empty behaves like IfNotPresent.
image_pull_policy = "IfNotPresent"
sandbox_namespace = "docker-dev"
# Empty auto-detects https://host.openshell.internal:<gateway-port> when guest TLS is set.
grpc_endpoint = "https://host.openshell.internal:17670"
# Skip the image-pull-and-extract step by pointing at a locally built binary.
supervisor_bin = "/usr/local/libexec/openshell/openshell-sandbox"
# When supervisor_bin is omitted, Docker extracts /openshell-sandbox from this image.
supervisor_image = "ghcr.io/nvidia/openshell/supervisor:latest"
guest_tls_ca = "/etc/openshell/certs/ca.pem"
guest_tls_cert = "/etc/openshell/certs/client.pem"
guest_tls_key = "/etc/openshell/certs/client-key.pem"
network_name = "openshell-docker"
host_gateway_ip = "172.17.0.1"
ssh_socket_path = "/run/openshell/ssh.sock"
# Unsafe operator override. Host bind mounts, including Docker local-driver
# bind-backed volumes, expose gateway-host paths inside sandboxes and can
# negate OpenShell isolation and filesystem controls.
enable_bind_mounts = false
# Set to 0 to leave Docker's runtime default unchanged.
sandbox_pids_limit = 2048
```
### Podman
Sandboxes run as Podman containers on a user-mode bridge network. The supervisor image is mounted read-only via Podman's `type=image` mount; guest mTLS material is supplied as host paths.
```toml
[openshell]
version = 1
[openshell.gateway]
bind_address = "127.0.0.1:17670"
log_level = "info"
compute_drivers = ["podman"]
[openshell.drivers.podman]
# Rootless socket path. For root Podman use /run/podman/podman.sock.
socket_path = "/run/user/1000/podman/podman.sock"
default_image = "ghcr.io/nvidia/openshell/sandbox:latest"
image_pull_policy = "missing" # always | missing | never | newer
grpc_endpoint = "https://host.containers.internal:17670"
# The gateway overwrites gateway_port from bind_address at runtime.
gateway_port = 17670
network_name = "openshell"
# Omit for the platform default: empty on Linux, 192.168.127.254 on macOS Podman machine.
# Set "" to force Podman's host-gateway resolver.
# host_gateway_ip = "192.168.127.254"
sandbox_ssh_socket_path = "/run/openshell/ssh.sock"
stop_timeout_secs = 10
supervisor_image = "ghcr.io/nvidia/openshell/supervisor:latest"
guest_tls_ca = "/etc/openshell/certs/ca.pem"
guest_tls_cert = "/etc/openshell/certs/client.pem"
guest_tls_key = "/etc/openshell/certs/client-key.pem"
# Unsafe operator override. Host bind mounts, including Podman local-driver
# bind-backed volumes, expose gateway-host paths inside sandboxes and can
# negate OpenShell isolation and filesystem controls.
enable_bind_mounts = false
# Set to 0 to leave Podman's runtime default unchanged.
sandbox_pids_limit = 2048
# Health check interval in seconds. Lower values detect readiness faster
# but increase process churn (each check spawns a conmon subprocess).
# Set to 0 to disable health checks entirely. Default: 10.
health_check_interval_secs = 10
```
### MicroVM
Each sandbox runs inside its own libkrun microVM managed by the standalone `openshell-driver-vm` subprocess. Use this driver when you want stronger isolation than container namespaces alone.
```toml
[openshell]
version = 1
[openshell.gateway]
bind_address = "127.0.0.1:17670"
log_level = "info"
# VM is never auto-detected; an explicit entry here is required.
compute_drivers = ["vm"]
[openshell.drivers.vm]
state_dir = "/var/lib/openshell/vm"
# Where the gateway looks for the openshell-driver-vm subprocess binary.
driver_dir = "/usr/local/libexec/openshell"
default_image = "ghcr.io/nvidia/openshell/sandbox:latest"
grpc_endpoint = "https://host.containers.internal:17670"
# Empty falls back to default_image.
bootstrap_image = "ghcr.io/nvidia/openshell/sandbox:latest"
krun_log_level = 1
vcpus = 2
mem_mib = 2048
overlay_disk_mib = 4096
guest_tls_ca = "/var/lib/openshell/guest-tls/ca.pem"
guest_tls_cert = "/var/lib/openshell/guest-tls/client.pem"
guest_tls_key = "/var/lib/openshell/guest-tls/client-key.pem"
# Resolved sandbox UID/GID for the rootfs /etc/passwd entry.
# Defaults to 10001 when unset; matching GID is used if sandbox_gid is empty.
# sandbox_uid = 20001
```
### Extension Driver
Extension drivers run outside the gateway and expose the
`compute_driver.proto` gRPC service on a Unix socket. Use a non-reserved driver
name; built-in names such as `vm`, `docker`, `podman`, and `kubernetes` cannot
be selected through unmanaged socket endpoints. The selected driver name is the
key used for driver-owned sandbox config such as `template.driver_config.<name>`.
```toml
[openshell]
version = 1
[openshell.gateway]
bind_address = "127.0.0.1:17670"
log_level = "info"
compute_drivers = ["kyma"]
[openshell.drivers.kyma]
socket_path = "/run/openshell/kyma-compute-driver.sock"
```
## Choosing Which Drivers Are Compiled In
Each built-in compute driver is gated by a Cargo feature on
`openshell-server`, all enabled by default. Operators who only need one
driver can produce a smaller gateway with a reduced supply-chain surface
by building `--no-default-features` and selecting a subset:
| Feature | Compiles in |
|---|---|
| `driver-kubernetes` | Kubernetes driver, K8s ServiceAccount authenticator, `kube-rs` and K8s client dependencies. |
| `driver-docker` | Docker driver, `bollard` and Docker-specific supervisor readiness plumbing. |
| `driver-podman` | Podman driver and libpod REST client. |
| `driver-vm` | In-server plumbing for spawning `openshell-driver-vm` and speaking to it over UDS. The driver binary itself is packaged separately. |
| `telemetry` | Anonymous telemetry emission. |
Kubernetes-only gateway:
```shell
cargo build --release -p openshell-server --bin openshell-gateway \
--no-default-features --features driver-kubernetes,telemetry
```
Docker + Podman gateway (drops K8s and VM code and their transitive
dependencies):
```shell
cargo build --release -p openshell-server --bin openshell-gateway \
--no-default-features --features driver-docker,driver-podman,telemetry
```
Extension-only gateway (no in-tree drivers; talks only to an out-of-tree
driver over a Unix socket) with disabled telemetry:
```shell
cargo build --release -p openshell-server --bin openshell-gateway --no-default-features
```
This build carries no built-in driver code. `compute_drivers` must name an
extension driver with a matching `[openshell.drivers.<name>].socket_path`.
Configuring a driver in `gateway.toml` that this gateway was not built with fails at startup with a
message naming both the driver and the Cargo flag that re-enables it.
Extension drivers reached via `--compute-driver-socket` do not depend on any
driver feature and work regardless.