exit

Documentation

Overview

Package exit implements the VPS-side HTTP handler. Apps Script POSTs AES-encrypted frame batches here; we decrypt, demux by session_id, dial real upstream targets on SYN, pump bytes between net.Conn and session, and long-poll the response so downstream bytes get delivered with low latency.

Index

• Constants
• type Config
• type Server
  • func New(cfg Config) (*Server, error)
  • func (s *Server) ListenAndServe() error
  • func (s *Server) ServeTunnel(w http.ResponseWriter, r *http.Request)
  • func (s *Server) StartBackground()

Constants

const (

	// ActiveDrainWindow caps how long a batch that just performed real work
	// (SYN/connect or non-empty uplink data) waits for downstream bytes.
	// Kept short so the client's single poll loop can quickly cycle back
	// and send SYN frames for other sessions that queued up while this poll
	// was in-flight. A long value here (e.g. 2s) causes head-of-line
	// blocking: when YouTube opens 4-6 parallel connections, later SYNs
	// are delayed by ActiveDrainWindow × (position in queue), easily
	// pushing total setup time past the player's ~7s abort threshold.
	ActiveDrainWindow = 350 * time.Millisecond

	// LongPollWindow is how long the handler holds open a request waiting for
	// downstream bytes. UrlFetchApp has a practical read timeout of ~10s, so
	// keep this comfortably below that.
	LongPollWindow = 8 * time.Second

	// MaxFramePayload caps the bytes per downstream frame (matches carrier).
	// Raised from 128KB: single-seal means no per-frame crypto cost, so fewer
	// larger frames are strictly better (less length-prefix overhead, fewer
	// Unmarshal calls). Must match the value in internal/carrier/client.go.
	MaxFramePayload = 256 * 1024
)

Types

type Config

type Config struct {
	ListenAddr    string // "0.0.0.0:8443"
	AESKeyHex     string // 64-char hex
	DebugTiming   bool   // when true, log per-session dial breakdown and first-read latency
	UpstreamProxy string // optional "host:port" of a local SOCKS5 proxy (e.g. WARP on 127.0.0.1:40000)
}

Config is the VPS server's configuration.

type Server

type Server struct {
	// contains filtered or unexported fields
}

Server holds the per-process session state.

func New

func New(cfg Config) (*Server, error)

New constructs an exit Server.

func (*Server) ListenAndServe

func (s *Server) ListenAndServe() error

ListenAndServe blocks. It binds an HTTP listener on cfg.ListenAddr with one route, POST /tunnel, that handles batched encrypted frames. Listens for SIGINT/SIGTERM and triggers graceful shutdown so in-flight long-polls drain.

func (*Server) ServeTunnel

func (s *Server) ServeTunnel(w http.ResponseWriter, r *http.Request)

ServeTunnel exposes the /tunnel handler so callers (e.g. integration test harnesses or alternative front-ends) can mount it on their own mux.

func (*Server) StartBackground

func (s *Server) StartBackground()

StartBackground starts the long-running maintenance goroutines (idle GC, stats loop, dialFail GC). It is intended for embed-style use where the caller drives an http.Server itself instead of calling ListenAndServe. Safe to call once per Server.