66e48bc933
The model-allowlist guardrail was merged into one account-wide union
and enforced flat on every request, independent of which policy,
group, or provider actually authorised it. With multiple policies —
especially a mix of guardrailed and un-guardrailed ones — this
produced two defects:
- false-allow: a model allowlisted for one group/provider leaked to
any caller, because the flat union ignored which policy authorised
the request; and
- false-deny: a policy with no guardrail (intended unrestricted) had
its traffic blocked by an unrelated policy's allowlist.
Make enforcement policy/group-aware, mirroring how llm_limit_check
already resolves caps:
- Management (SelectPolicyForRequest) is authoritative. It now uses
the request model (already carried on the wire in
CheckLLMPolicyLimitsRequest.model, previously ignored) to keep only
the applicable policies whose guardrails permit the model; a policy
with no allowlist-enabled guardrail is unrestricted. When policies
govern the (provider, groups) but none permits the model it denies
with llm_policy.model_blocked. No proto change — the field already
existed and the proxy already sends it.
- The proxy llm_guardrail becomes a per-provider fail-closed backstop.
The synthesiser emits a per-provider allowlist only when every
policy authorising that provider restricts models; a provider
reachable by any un-guardrailed policy is omitted (unrestricted).
The middleware keys the allowlist by the resolved provider id and
keeps the unknown/undetermined-model fail-closed behaviour so
path-routed providers stay enforced when management is unreachable.
Unit tests cover the selector gate (block, allow, cross-group no-leak,
un-guardrailed policy unrestricted, undetermined-model fail-closed) and
the per-provider synthesis; an e2e proves all three properties end to
end over the tunnel. Docs updated for the new config shape and the
two-layer enforcement.
Netbird Reverse Proxy
The NetBird Reverse Proxy is a separate service that can act as a public entrypoint to certain resources within a NetBird network. At a high level, the way that it operates is:
- Configured routes are communicated from the Management server to the proxy.
- For each route the proxy creates a NetBird connection to the NetBird Peer that hosts the resource.
- When traffic hits the proxy at the address and path configured for the proxied resource, the NetBird Proxy brings up a relevant authentication method for that resource.
- On successful authentication the proxy will forward traffic onwards to the NetBird Peer.
Proxy Authentication methods supported are:
- No authentication
- Oauth2/OIDC
- Emailed Magic Link
- Simple PIN
- HTTP Basic Auth Username and Password
Management Connection and Authentication
The Proxy communicates with the Management server over a gRPC connection. Proxies act as clients to the Management server, the following RPCs are used:
- Server-side streaming for proxied service updates.
- Client-side streaming for proxy logs.
To authenticate with the Management server, the proxy server uses Machine-to-Machine OAuth2. If you are using the embedded IdP //TODO: explain how to get credentials. Otherwise, create a new machine-to-machine profile in your IdP for proxy servers and set the relevant settings in the proxy's environment or flags (see below).
User Authentication
When a request hits the Proxy, it looks up the permitted authentication methods for the Host domain. If no authentication methods are registered for the Host domain, then no authentication will be applied (for fully public resources). If any authentication methods are registered for the Host domain, then the Proxy will first serve an authentication page allowing the user to select an authentication method (from the permitted methods) and enter the required information for that authentication method. If the user is successfully authenticated, their request will be forwarded through to the Proxy to be proxied to the relevant Peer. Successful authentication does not guarantee a successful forwarding of the request as there may be failures behind the Proxy, such as with Peer connectivity or the underlying resource.
TLS
Due to the authentication provided, the Proxy uses HTTPS for its endpoint, even if the underlying service is HTTP.
Certificate generation can either be via ACME (by default, using Let's Encrypt, but alternative ACME providers can be used) or through certificate files.
When not using ACME, the proxy server attempts to load a certificate and key from the files tls.crt and tls.key in a specified certificate directory.
When using ACME, the proxy server will store generated certificates in the specified certificate directory.
Auth UI
The authentication UI is a Vite + React application located in the web/ directory. It is embedded into the Go binary at build time.
To build the UI:
cd web
npm install
npm run build
For UI development with hot reload (served at http://localhost:3031):
npm run dev
The built assets in web/dist/ are embedded via //go:embed and served by the web.ServeHTTP handler.
Configuration
NetBird Proxy deployment configuration is via flags or environment variables, with flags taking precedence over the environment. The following deployment configuration is available:
| Flag | Env | Purpose | Default |
|---|---|---|---|
-debug |
NB_PROXY_DEBUG_LOGS |
Enable debug logging | false |
-mgmt |
NB_PROXY_MANAGEMENT_ADDRESS |
The address of the management server for the proxy to get configuration from. | "https://api.netbird.io:443" |
-addr |
NB_PROXY_ADDRESS |
The address that the reverse proxy will listen on. | ":443 |
-url |
NB_PROXY_URL |
The URL that the proxy will be reached at (where endpoints will be CNAMEd to). If unset, this will fall back to the proxy address. | "proxy.netbird.io" |
-cert-dir |
NB_PROXY_CERTIFICATE_DIRECTORY |
The location that certificates are stored in. | "./certs" |
-acme-certs |
NB_PROXY_ACME_CERTIFICATES |
Whether to use ACME to generate certificates. | false |
-acme-addr |
NB_PROXY_ACME_ADDRESS |
The HTTP address the proxy will listen on to respond to HTTP-01 ACME challenges | ":80" |
-acme-dir |
NB_PROXY_ACME_DIRECTORY |
The directory URL of the ACME server to be used | "https://acme-v02.api.letsencrypt.org/directory" |
-oidc-id |
NB_PROXY_OIDC_CLIENT_ID |
The OAuth2 Client ID for OIDC User Authentication | "netbird-proxy" |
-oidc-secret |
NB_PROXY_OIDC_CLIENT_SECRET |
The OAuth2 Client Secret for OIDC User Authentication | "" |
-oidc-endpoint |
NB_PROXY_OIDC_ENDPOINT |
The OAuth2 provider endpoint for OIDC User Authentication | "https://api.netbird.io/oauth2" |
-oidc-scopes |
NB_PROXY_OIDC_SCOPES |
The OAuth2 scopes for OIDC User Authentication, comma separated | "openid,profile,email" |