Struct TcpConnectionTracker 

pub struct TcpConnectionTracker { /* private fields */ }

Tracks TCP connections between guest and proxy tasks.

Each guest TCP connection maps to a smoltcp socket and a pair of channels connecting it to a tokio proxy task. The tracker handles:

• Socket creation — on SYN detection, before smoltcp processes the frame.
• Data relay — shuttles bytes between smoltcp sockets and channels.
• Lifecycle detection — identifies newly-established connections for proxy spawning.
• Cleanup — removes closed sockets from the socket set.

Implementations

impl TcpConnectionTracker

pub fn new(max_tcp_connections: Option<NonZeroUsize>) -> Self

Create a new tracker with the given connection limit.

pub fn has_socket_for(&self, src: &SocketAddr, dst: &SocketAddr) -> bool

Returns true if a tracked socket already exists for this exact connection (same source AND destination). O(1) via HashSet lookup.

pub fn create_tcp_socket( &mut self, src: SocketAddr, dst: SocketAddr, sockets: &mut SocketSet<'_>, mode: TcpAcceptMode, ) -> bool

Create a destination-bound socket using the policy’s handshake mode. src and dst are guest-visible addresses; mode is the policy decision. Returns false when the mode rejects the connection or the budget is full.

pub fn relay_data(&mut self, sockets: &mut SocketSet<'_>)

Relay data between smoltcp sockets and proxy task channels.

For each connection with a spawned proxy:

• Reads data from the smoltcp socket and sends it to the proxy channel.
• Receives data from the proxy channel and writes it to the smoltcp socket.

pub fn take_new_connections( &mut self, sockets: &mut SocketSet<'_>, ) -> Vec<NewConnection>

Collect newly-established connections that need proxy tasks.

Returns a list of NewConnection structs containing the channel ends for the proxy task. The poll loop is responsible for spawning the task.

pub fn trace_stats(&self, sockets: &SocketSet<'_>)

Record bounded-cardinality diagnostics once per maintenance interval.

pub fn cleanup_closed(&mut self, sockets: &mut SocketSet<'_>)

Remove closed connections and their sockets.

Idle listeners represent failed/reset SYNs: this tracker never owns persistent listening sockets. Closed sockets with a remote endpoint still owe the guest an RST and must survive until smoltcp emits it. TIME_WAIT remains intact to reject delayed duplicate segments.