Zoltán Papp
5df35e3e27
Nothing recorded which run of the connection was current, so three defects followed from the same gap. A ConnectClient is single-use, and the daemon builds a fresh one per outer-retry turn (server.go connect). Each turn overwrote s.connectClient and nothing stopped the one it replaced — the outgoing run loop had returned, which is what brought control back to the retry, but that was assumed rather than enforced, and any teardown its error path left half-done got no second chance. cleanupConnection read s.connectClient, cancelled, then stopped that engine. Nothing established the client it read was still current by the time it stopped it, so a teardown could target a client a newer turn had already replaced and leave the live one running untracked. Down's wait on clientGiveUpChan and Up's refusal to start a second loop kept the window narrow, but by arrangement rather than by construction. Third, the engine was stopped twice concurrently: actCancel woke the run loop, which stops the engine on its way out, while cleanupConnection stopped the same engine directly. The TODO there said ConnectClient.Stop was the right call and that its unbounded wait was what ruled it out. RunSupervisor records the generation of the current run. Publish refuses a client from a superseded run and stops the client it displaces, so no ConnectClient is dropped without being stopped. Stop invalidates whatever run is in flight, stops the published client and waits for the run to exit. ConnectClient.StopWithContext bounds that wait, which removes the TODO's obstacle: cleanupConnection now hands the run loop sole ownership of engine shutdown and passes Down's 5s budget down. Stop() keeps its signature and its unbounded wait, so callers outside this change are untouched. embed.Client.Stop had built the same bound by hand with a goroutine and a select purely to watch its caller's context; it passes the context down instead. clientGiveUpChan and connectClient are gone — the supervisor answers both. The MDM restart path drops its hand-rolled 10s channel wait for the same Stop, which additionally stops the client the previous run left behind. Its deliberate choice to leave clientRunning set is unchanged. Down now waits inside cleanupConnection, under s.mutex, where it previously waited after releasing it. That is what pins the client being stopped to the one current when the call started; the cost is that Down can hold the mutex for up to its 5s budget. Found while fixing the iOS wifi-to-cellular black-hole (#7329), which was the same class of defect in the mobile SDKs. No bug report backs the daemon findings — they are read off the code, and the narrow windows above may be why they have not been observed.
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🤖 NetBird Agent Network (Beta)
Identity-aware access control for AI agents — keyless access to LLM APIs and private resources over the encrypted NetBird tunnel. See
agent-network/or read the docs at netbird.ai.
NetBird combines a configuration-free peer-to-peer private network and a centralized access control system in a single platform, making it easy to create secure private networks for your organization or home.
Connect. NetBird creates a WireGuard-based overlay network that automatically connects your machines over an encrypted tunnel, leaving behind the hassle of opening ports, complex firewall rules, VPN gateways, and so forth.
Secure. NetBird enables secure remote access by applying granular access policies while allowing you to manage them intuitively from a single place. Works universally on any infrastructure.
https://github.com/user-attachments/assets/10cec749-bb56-4ab3-97af-4e38850108d2
Self-host NetBird (video)
Key features
Quickstart with NetBird Cloud
- Download and install NetBird at https://app.netbird.io/install.
- Follow the steps to sign up with Google, Microsoft, GitHub or your email address.
- Check the NetBird admin UI.
Quickstart with self-hosted NetBird
This is the quickest way to try self-hosted NetBird. It should take around 5 minutes to get started if you already have a public domain and a VM. Follow the Advanced guide with a custom identity provider for installations with different IdPs.
Infrastructure requirements:
- A Linux VM with at least 1 CPU and 2 GB of memory.
- The VM should be publicly accessible on TCP ports 80 and 443 and UDP port 3478.
- A public domain name pointing to the VM.
Software requirements:
- Docker with the Compose plugin (Compose v2 or higher). See the Docker installation guide.
Steps
- Download and run the installation script:
export NETBIRD_DOMAIN=netbird.example.com; curl -fsSL https://github.com/netbirdio/netbird/releases/latest/download/getting-started.sh | bash
A bit on NetBird internals
- Every machine in the network runs the NetBird agent, which manages WireGuard.
- Every agent connects to the Management Service, which holds network state, manages peer IPs, and distributes updates to agents.
- Agents use ICE (via pion/ice) to discover connection candidates for peer-to-peer connections.
- Candidates are discovered with the help of STUN servers.
- Agents negotiate a connection through the Signal Service, exchanging end-to-end encrypted messages with candidates.
- When NAT traversal fails (e.g. mobile carrier-grade NAT) and a direct p2p connection isn't possible, the system falls back to a Relay Service and a secure WireGuard tunnel is established through it.
See a complete architecture overview for details.
Community projects
- NetBird installer script
- netbird-tui - terminal UI for managing NetBird peers, routes, and settings
- caddy-netbird - Caddy plugin that embeds a NetBird client for proxying HTTP and TCP/UDP traffic through NetBird networks
Note: The main branch may be in an unstable or even broken state during development.
For stable versions, see releases.
Support acknowledgement
In November 2022, NetBird joined the StartUpSecure program sponsored by the Federal Ministry of Education and Research of the Federal Republic of Germany. Together with the CISPA Helmholtz Center for Information Security, NetBird brings security best practices and simplicity to private networking.
Acknowledgements
We build on open source technologies like WireGuard®, Pion ICE, and Rosenpass. We greatly appreciate the work these projects are doing, and we'd love it if you could support them too (e.g., by starring or contributing).
Legal
This repository is licensed under the BSD-3-Clause license, which applies to all parts of the repository except for the directories management/, signal/ and relay/. Those directories are licensed under the GNU Affero General Public License version 3.0 (AGPLv3). See the respective LICENSE files inside each directory.
WireGuard and the WireGuard logo are registered trademarks of Jason A. Donenfeld.