mirror of
https://github.com/netbirdio/netbird.git
synced 2026-10-02 19:49:07 +02:00
Riccardo Manfrin
9f8ddc7131
* [client] Discover interfaces lazily in stdnet instead of at construction
stdnet.NewNet and NewNetWithDiscover ended with
return n, n.UpdateInterfaces()
handing back a non-nil *Net together with the discovery error. Three of the
five call sites (Engine.newWgIface, ice.NewAgent, SingleSocketUDPMux) logged
the error and kept using the instance, which is only safe as long as the
instance still works after a failed discovery.
That stopped being true when Interfaces() gained a lazily refreshed cache:
updateInterfaces sets lastUpdate only on success, so after a failed
construction the 30s cache guard never holds and Interfaces() returns an
error rather than the empty list it used to return. Feeding such an instance
to pion is worse than passing nothing at all - ice.NewAgent falls back to its
own stdnet when Net is nil, and the interface blacklist is applied separately
through AgentConfig.InterfaceFilter, so the fallback loses nothing. Instead,
a transient discovery failure (the Android bridge at boot, or an interface
disappearing between net.Interfaces() and Interface.Addrs()) turned into a
hard "error getting local interfaces" from ice.NewAgent, and aborted the STUN
and TURN probes, which never even need the interface list.
Since the accessors already refresh a stale cache on demand, the eager
discovery in the constructors is redundant: drop it, make both constructors
infallible, and let the discovery error surface at the call that actually
needs the interfaces. UpdateInterfaces had no callers left and is not part of
transport.Net, so it is removed along with it.
InterfaceByIndex and InterfaceByName read the cached slice directly and never
refreshed it, so they would have kept reporting ErrInterfaceNotFound forever
on an instance whose first discovery failed. They now go through the same
refresh path as Interfaces().
* [client] Warm the stdnet interface cache at construction
Moving discovery to first use regressed the privileged suites on the three
platforms that always build an ICE bind: Darwin, FreeBSD and Windows time out
in TestWGIface_UpdateAddr, TestRecreation, TestEngine_SSH and
TestEngine_MultiplePeers, while Linux stays green because a host with the
WireGuard kernel module takes the kernel-device branch and never drives the
mux that asks for interfaces.
interfaceFilter probes with wgctrl every interface the disallow list does not
already exclude. Discovering at construction ran that probe before the caller
had an overlay interface of its own; discovering at first use runs it after,
so on a userspace WireGuard platform the probe reaches the UAPI socket of the
same process. The tests reach it because they construct with a nil disallow
list, where the client passes DefaultInterfaceBlacklist and its own interface
is excluded by prefix.
Restore the original timing with an explicit warm-up. The constructors stay
infallible and the error is still reported by the accessor that needs the
interfaces, so the contract this branch is about is unchanged.
* Revert "[client] Warm the stdnet interface cache at construction"
This reverts commit 947e25288f.
* [client] Give the privileged tests the interface blacklist the client uses
The suites that create a WireGuard interface construct stdnet with a nil
disallow list, which the client never does: Engine passes
profilemanager.DefaultInterfaceBlacklist, whose "wt" and "utun" prefixes
exclude the overlay interface before the filter reaches its wgctrl probe.
With an empty list every interface reaches that probe, the one the test has
just created included, and on a userspace WireGuard platform the probe talks
to the UAPI socket of the same process. That is why Darwin, FreeBSD and
Windows timed out here while Linux, which takes the kernel-device branch on a
host with the module loaded, stayed green.
Pass the blacklist in both suites so they exercise the configuration the
client ships. client/iface declares the prefixes locally because
profilemanager imports it.
Also cover the constructors directly: the existing tests build the struct
literal, so nothing asserted that NewNet and NewNetWithDiscover leave the
cache cold.
* [client] Pass the blacklist in the remaining tests that build an interface
Same reason as the previous commit, four call sites it missed: engine_test,
the route manager and systemops suites, and the privileged DNS server suite
all construct stdnet with a nil disallow list and then create a WireGuard
interface. TestAddVPNRoute surfaced it on FreeBSD once the earlier two files
stopped timing out first.
client/internal/dns declares the prefixes locally; profilemanager imports
that package, so it cannot import profilemanager back.