Reaching an internal service meant installing the agent, which needs root
for a TUN device. nblink runs the embedded client in netstack mode and
forwards local HTTP listeners to upstreams inside the tunnel, so it works on
managed machines and in rootless containers. Upstream names resolve
in-process.
Forwards bind loopback unless --allow-public-bind is given. The listener
refuses rebound and cross-site browser requests and bounds stalled request
bodies. It ships as release archives and a distroless image that runs under
an arbitrary UID.
An embedded client given no StatePath now keeps its state in memory rather
than falling back to the installed agent's state file, which every embedded
client in a proxy process also shared. The state manager gets an explicit
in-memory store for it.
Losing the last network only flipped the availability state: the dead management, signal and relay sockets stayed silently connected until their own timeouts, so the client kept reporting Connected with no network at all.
Introduce client/netevents with a Manager that ties the availability state, the connection sweeper and the status recorder together, and move the netstate and netsweep packages under it (netsweep renamed to sweep). SetNetworkAvailable(false) now also sweeps the registered connections so their owners redial and the listener reaches the NoNetwork state.
The Android and iOS bindings own a Manager instance and inject it through the constructors; consumers hold the concrete *Manager whose nil zero value reports always-online and never sweeps, with interfaces kept only as parameter contracts. The relay guard settle wait moved into the Manager as WaitSettled, removing the netevents import from the relay package.
On network changes the client restarted the whole engine. That is heavy-handed and slow: it tears down working state to recover from a transition the engine could handle itself. This replaces the restart with proper network event handling.
Suspend the retry loops while no network is available. Instead of burning through backoff intervals against an unreachable network, the reconnection loops park until the OS reports a usable network again.
Reconnect immediately on a network switch. When the OS hands us a new network, connections bound to the old one are swept and re-dialed right away, rather than waiting for a timeout to notice they are dead.
Maycon Santos