Add Surge MITM and scripts

script/source_remote.go

@@ -0,0 +1,224 @@
+package script
+
+import (
+	"context"
+	"crypto/tls"
+	"io"
+	"net"
+	"net/http"
+	"runtime"
+	"time"
+
+	"github.com/sagernet/sing-box/adapter"
+	C "github.com/sagernet/sing-box/constant"
+	"github.com/sagernet/sing-box/option"
+	E "github.com/sagernet/sing/common/exceptions"
+	F "github.com/sagernet/sing/common/format"
+	"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"
+	"github.com/sagernet/sing/service"
+	"github.com/sagernet/sing/service/pause"
+
+	"github.com/dop251/goja"
+)
+
+var _ Source = (*RemoteSource)(nil)
+
+type RemoteSource struct {
+	ctx            context.Context
+	cancel         context.CancelFunc
+	logger         logger.Logger
+	outbound       adapter.OutboundManager
+	options        option.Script
+	updateInterval time.Duration
+	dialer         N.Dialer
+	program        *goja.Program
+	lastUpdated    time.Time
+	lastEtag       string
+	updateTicker   *time.Ticker
+	cacheFile      adapter.CacheFile
+	pauseManager   pause.Manager
+}
+
+func NewRemoteSource(ctx context.Context, logger logger.Logger, options option.Script) (*RemoteSource, error) {
+	ctx, cancel := context.WithCancel(ctx)
+	var updateInterval time.Duration
+	if options.RemoteOptions.UpdateInterval > 0 {
+		updateInterval = time.Duration(options.RemoteOptions.UpdateInterval)
+	} else {
+		updateInterval = 24 * time.Hour
+	}
+	return &RemoteSource{
+		ctx:            ctx,
+		cancel:         cancel,
+		logger:         logger,
+		outbound:       service.FromContext[adapter.OutboundManager](ctx),
+		options:        options,
+		updateInterval: updateInterval,
+		pauseManager:   service.FromContext[pause.Manager](ctx),
+	}, nil
+}
+
+func (s *RemoteSource) StartContext(ctx context.Context, startContext *adapter.HTTPStartContext) error {
+	s.cacheFile = service.FromContext[adapter.CacheFile](s.ctx)
+	var dialer N.Dialer
+	if s.options.RemoteOptions.DownloadDetour != "" {
+		outbound, loaded := s.outbound.Outbound(s.options.RemoteOptions.DownloadDetour)
+		if !loaded {
+			return E.New("download detour not found: ", s.options.RemoteOptions.DownloadDetour)
+		}
+		dialer = outbound
+	} else {
+		dialer = s.outbound.Default()
+	}
+	s.dialer = dialer
+	if s.cacheFile != nil {
+		if savedSet := s.cacheFile.LoadScript(s.options.Tag); savedSet != nil {
+			err := s.loadBytes(savedSet.Content)
+			if err != nil {
+				return E.Cause(err, "restore cached rule-set")
+			}
+			s.lastUpdated = savedSet.LastUpdated
+			s.lastEtag = savedSet.LastEtag
+		}
+	}
+	if s.lastUpdated.IsZero() {
+		err := s.fetchOnce(ctx, startContext)
+		if err != nil {
+			return E.Cause(err, "initial rule-set: ", s.options.Tag)
+		}
+	}
+	s.updateTicker = time.NewTicker(s.updateInterval)
+	return nil
+}
+
+func (s *RemoteSource) PostStart() error {
+	go s.loopUpdate()
+	return nil
+}
+
+func (s *RemoteSource) Program() *goja.Program {
+	return s.program
+}
+
+func (s *RemoteSource) loadBytes(content []byte) error {
+	program, err := goja.Compile(F.ToString("script:", s.options.Tag), string(content), false)
+	if err != nil {
+		return err
+	}
+	s.program = program
+	return nil
+}
+
+func (s *RemoteSource) loopUpdate() {
+	if time.Since(s.lastUpdated) > s.updateInterval {
+		err := s.fetchOnce(s.ctx, nil)
+		if err != nil {
+			s.logger.Error("fetch rule-set ", s.options.Tag, ": ", err)
+		}
+	}
+	for {
+		runtime.GC()
+		select {
+		case <-s.ctx.Done():
+			return
+		case <-s.updateTicker.C:
+			s.pauseManager.WaitActive()
+			err := s.fetchOnce(s.ctx, nil)
+			if err != nil {
+				s.logger.Error("fetch rule-set ", s.options.Tag, ": ", err)
+			}
+		}
+	}
+}
+
+func (s *RemoteSource) fetchOnce(ctx context.Context, startContext *adapter.HTTPStartContext) error {
+	s.logger.Debug("updating script ", s.options.Tag, " from URL: ", s.options.RemoteOptions.URL)
+	var httpClient *http.Client
+	if startContext != nil {
+		httpClient = startContext.HTTPClient(s.options.RemoteOptions.DownloadDetour, s.dialer)
+	} else {
+		httpClient = &http.Client{
+			Transport: &http.Transport{
+				ForceAttemptHTTP2:   true,
+				TLSHandshakeTimeout: C.TCPTimeout,
+				DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+					return s.dialer.DialContext(ctx, network, M.ParseSocksaddr(addr))
+				},
+				TLSClientConfig: &tls.Config{
+					Time:    ntp.TimeFuncFromContext(s.ctx),
+					RootCAs: adapter.RootPoolFromContext(s.ctx),
+				},
+			},
+		}
+	}
+	request, err := http.NewRequest("GET", s.options.RemoteOptions.URL, nil)
+	if err != nil {
+		return err
+	}
+	if s.lastEtag != "" {
+		request.Header.Set("If-None-Match", s.lastEtag)
+	}
+	response, err := httpClient.Do(request.WithContext(ctx))
+	if err != nil {
+		return err
+	}
+	switch response.StatusCode {
+	case http.StatusOK:
+	case http.StatusNotModified:
+		s.lastUpdated = time.Now()
+		if s.cacheFile != nil {
+			savedRuleSet := s.cacheFile.LoadScript(s.options.Tag)
+			if savedRuleSet != nil {
+				savedRuleSet.LastUpdated = s.lastUpdated
+				err = s.cacheFile.SaveScript(s.options.Tag, savedRuleSet)
+				if err != nil {
+					s.logger.Error("save script updated time: ", err)
+					return nil
+				}
+			}
+		}
+		s.logger.Info("update script ", s.options.Tag, ": not modified")
+		return nil
+	default:
+		return E.New("unexpected status: ", response.Status)
+	}
+	content, err := io.ReadAll(response.Body)
+	if err != nil {
+		response.Body.Close()
+		return err
+	}
+	err = s.loadBytes(content)
+	if err != nil {
+		response.Body.Close()
+		return err
+	}
+	response.Body.Close()
+	eTagHeader := response.Header.Get("Etag")
+	if eTagHeader != "" {
+		s.lastEtag = eTagHeader
+	}
+	s.lastUpdated = time.Now()
+	if s.cacheFile != nil {
+		err = s.cacheFile.SaveScript(s.options.Tag, &adapter.SavedBinary{
+			LastUpdated: s.lastUpdated,
+			Content:     content,
+			LastEtag:    s.lastEtag,
+		})
+		if err != nil {
+			s.logger.Error("save script cache: ", err)
+		}
+	}
+	s.logger.Info("updated script ", s.options.Tag)
+	return nil
+}
+
+func (s *RemoteSource) Close() error {
+	if s.updateTicker != nil {
+		s.updateTicker.Stop()
+	}
+	s.cancel()
+	return nil
+}