refactor: Modular inbounds/outbounds

protocol/shadowsocks/inbound.go

@@ -0,0 +1,179 @@
+package shadowsocks
+
+import (
+	"context"
+	"net"
+	"time"
+
+	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing-box/adapter/inbound"
+	"github.com/sagernet/sing-box/common/listener"
+	"github.com/sagernet/sing-box/common/mux"
+	"github.com/sagernet/sing-box/common/uot"
+	C "github.com/sagernet/sing-box/constant"
+	"github.com/sagernet/sing-box/log"
+	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing-shadowsocks"
+	"github.com/sagernet/sing-shadowsocks/shadowaead"
+	"github.com/sagernet/sing-shadowsocks/shadowaead_2022"
+	"github.com/sagernet/sing/common"
+	"github.com/sagernet/sing/common/buf"
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
+	M "github.com/sagernet/sing/common/metadata"
+	N "github.com/sagernet/sing/common/network"
+	"github.com/sagernet/sing/common/ntp"
+)
+
+func RegisterInbound(registry *inbound.Registry) {
+	inbound.Register[option.ShadowsocksInboundOptions](registry, C.TypeShadowsocks, NewInbound)
+}
+
+func NewInbound(ctx context.Context, router adapter.Router, logger log.ContextLogger, tag string, options option.ShadowsocksInboundOptions) (adapter.Inbound, error) {
+	if len(options.Users) > 0 && len(options.Destinations) > 0 {
+		return nil, E.New("users and destinations options must not be combined")
+	}
+	if len(options.Users) > 0 {
+		return newMultiInbound(ctx, router, logger, tag, options)
+	} else if len(options.Destinations) > 0 {
+		return newRelayInbound(ctx, router, logger, tag, options)
+	} else {
+		return newInbound(ctx, router, logger, tag, options)
+	}
+}
+
+var _ adapter.TCPInjectableInbound = (*Inbound)(nil)
+
+type Inbound struct {
+	inbound.Adapter
+	ctx      context.Context
+	router   adapter.ConnectionRouterEx
+	logger   logger.ContextLogger
+	listener *listener.Listener
+	service  shadowsocks.Service
+}
+
+func newInbound(ctx context.Context, router adapter.Router, logger log.ContextLogger, tag string, options option.ShadowsocksInboundOptions) (*Inbound, error) {
+	inbound := &Inbound{
+		Adapter: inbound.NewAdapter(C.TypeShadowsocks, tag),
+		ctx:     ctx,
+		router:  uot.NewRouter(router, logger),
+		logger:  logger,
+	}
+	var err error
+	inbound.router, err = mux.NewRouterWithOptions(router, logger, common.PtrValueOrDefault(options.Multiplex))
+	if err != nil {
+		return nil, err
+	}
+	var udpTimeout time.Duration
+	if options.UDPTimeout != 0 {
+		udpTimeout = time.Duration(options.UDPTimeout)
+	} else {
+		udpTimeout = C.UDPTimeout
+	}
+	switch {
+	case options.Method == shadowsocks.MethodNone:
+		inbound.service = shadowsocks.NewNoneService(int64(udpTimeout.Seconds()), adapter.NewUpstreamHandler(adapter.InboundContext{}, inbound.newConnection, inbound.newPacketConnection, inbound))
+	case common.Contains(shadowaead.List, options.Method):
+		inbound.service, err = shadowaead.NewService(options.Method, nil, options.Password, int64(udpTimeout.Seconds()), adapter.NewUpstreamHandler(adapter.InboundContext{}, inbound.newConnection, inbound.newPacketConnection, inbound))
+	case common.Contains(shadowaead_2022.List, options.Method):
+		inbound.service, err = shadowaead_2022.NewServiceWithPassword(options.Method, options.Password, int64(udpTimeout.Seconds()), adapter.NewUpstreamHandler(adapter.InboundContext{}, inbound.newConnection, inbound.newPacketConnection, inbound), ntp.TimeFuncFromContext(ctx))
+	default:
+		err = E.New("unsupported method: ", options.Method)
+	}
+	inbound.listener = listener.New(listener.Options{
+		Context:                  ctx,
+		Logger:                   logger,
+		Network:                  options.Network.Build(),
+		Listen:                   options.ListenOptions,
+		ConnectionHandler:        inbound,
+		PacketHandler:            inbound,
+		ThreadUnsafePacketWriter: true,
+	})
+	return inbound, err
+}
+
+func (h *Inbound) Start() error {
+	return h.listener.Start()
+}
+
+func (h *Inbound) Close() error {
+	return h.listener.Close()
+}
+
+func (h *Inbound) NewConnectionEx(ctx context.Context, conn net.Conn, metadata adapter.InboundContext, onClose N.CloseHandlerFunc) {
+	err := h.service.NewConnection(ctx, conn, adapter.UpstreamMetadata(metadata))
+	N.CloseOnHandshakeFailure(conn, onClose, err)
+	if err != nil {
+		h.logger.ErrorContext(ctx, E.Cause(err, "process connection from ", metadata.Source))
+	}
+}
+
+func (h *Inbound) NewPacketEx(buffer *buf.Buffer, source M.Socksaddr) {
+	err := h.service.NewPacket(h.ctx, &stubPacketConn{h.listener.PacketWriter()}, buffer, M.Metadata{Source: source})
+	if err != nil {
+		h.logger.Error(E.Cause(err, "process packet from ", source))
+	}
+}
+
+func (h *Inbound) newConnection(ctx context.Context, conn net.Conn, metadata adapter.InboundContext) error {
+	h.logger.InfoContext(ctx, "inbound connection to ", metadata.Destination)
+	metadata.Inbound = h.Tag()
+	metadata.InboundType = h.Type()
+	return h.router.RouteConnection(ctx, conn, metadata)
+}
+
+func (h *Inbound) newPacketConnection(ctx context.Context, conn N.PacketConn, metadata adapter.InboundContext) error {
+	ctx = log.ContextWithNewID(ctx)
+	h.logger.InfoContext(ctx, "inbound packet connection from ", metadata.Source)
+	h.logger.InfoContext(ctx, "inbound packet connection to ", metadata.Destination)
+	metadata.Inbound = h.Tag()
+	metadata.InboundType = h.Type()
+	metadata.InboundDetour = h.listener.ListenOptions().Detour
+	metadata.InboundOptions = h.listener.ListenOptions().InboundOptions
+	return h.router.RoutePacketConnection(ctx, conn, metadata)
+}
+
+var _ N.PacketConn = (*stubPacketConn)(nil)
+
+type stubPacketConn struct {
+	N.PacketWriter
+}
+
+func (c *stubPacketConn) ReadPacket(buffer *buf.Buffer) (destination M.Socksaddr, err error) {
+	panic("stub!")
+}
+
+func (c *stubPacketConn) Close() error {
+	return nil
+}
+
+func (c *stubPacketConn) LocalAddr() net.Addr {
+	panic("stub!")
+}
+
+func (c *stubPacketConn) SetDeadline(t time.Time) error {
+	panic("stub!")
+}
+
+func (c *stubPacketConn) SetReadDeadline(t time.Time) error {
+	panic("stub!")
+}
+
+func (c *stubPacketConn) SetWriteDeadline(t time.Time) error {
+	panic("stub!")
+}
+
+func (h *Inbound) NewError(ctx context.Context, err error) {
+	NewError(h.logger, ctx, err)
+}
+
+// Deprecated: remove
+func NewError(logger logger.ContextLogger, ctx context.Context, err error) {
+	common.Close(err)
+	if E.IsClosedOrCanceled(err) {
+		logger.DebugContext(ctx, "connection closed: ", err)
+		return
+	}
+	logger.ErrorContext(ctx, err)
+}