Viktor Liu
603e163d42
HTTP_1_1_REQUIRED is not a fault: it is the upstream describing its own configuration. IIS answers it for sites using Windows Authentication — connection-oriented auth that h2 multiplexing cannot carry — and for client-certificate sites, where the per-request certificate needs a TLS renegotiation h2 forbids. Browsers retry those on HTTP/1.1 silently, which is why such a site works in a browser and fails behind this proxy. Expiring that pin every 10 minutes would buy nothing but one failed request per interval, since nothing about the upstream has changed. So a pin the upstream asked for holds until the transport goes away with the proxy or the account's client, and the bounded TTL stays for the ambiguous protocol errors, where the failure may well clear on its own. A later ambiguous failure never weakens a permanent pin.
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" |