Shadowsocks loop

2020-07-08 23:29:40 +00:00
parent a39d885e34
commit 8669748289
2 changed files with 123 additions and 26 deletions
--- a/internal/shadowsocks/loop.go
+++ b/internal/shadowsocks/loop.go
@@ -0,0 +1,114 @@
+package shadowsocks
+
+import (
+	"context"
+	"time"
+
+	"github.com/qdm12/golibs/command"
+	"github.com/qdm12/golibs/logging"
+	"github.com/qdm12/private-internet-access-docker/internal/constants"
+	"github.com/qdm12/private-internet-access-docker/internal/firewall"
+	"github.com/qdm12/private-internet-access-docker/internal/settings"
+)
+
+type Looper interface {
+	Run(ctx context.Context, restart <-chan struct{}, done chan<- struct{})
+}
+
+type looper struct {
+	conf         Configurator
+	firewallConf firewall.Configurator
+	settings     settings.ShadowSocks
+	dnsSettings  settings.DNS
+	logger       logging.Logger
+	streamMerger command.StreamMerger
+	uid          int
+	gid          int
+}
+
+func (l *looper) logAndWait(err error) {
+	l.logger.Error(err)
+	l.logger.Info("retrying in 1 minute")
+	time.Sleep(time.Minute)
+}
+
+func NewLooper(conf Configurator, firewallConf firewall.Configurator, settings settings.ShadowSocks, dnsSettings settings.DNS,
+	logger logging.Logger, streamMerger command.StreamMerger, uid, gid int) Looper {
+	return &looper{
+		conf:         conf,
+		firewallConf: firewallConf,
+		settings:     settings,
+		dnsSettings:  dnsSettings,
+		logger:       logger.WithPrefix("shadowsocks: "),
+		streamMerger: streamMerger,
+		uid:          uid,
+		gid:          gid,
+	}
+}
+
+func (l *looper) Run(ctx context.Context, restart <-chan struct{}, done chan<- struct{}) {
+	select {
+	case <-restart:
+	case <-ctx.Done():
+		close(done)
+		return
+	}
+	for {
+		nameserver := l.dnsSettings.PlaintextAddress.String()
+		if l.dnsSettings.Enabled {
+			nameserver = "127.0.0.1"
+		}
+		err := l.conf.MakeConf(
+			l.settings.Port,
+			l.settings.Password,
+			l.settings.Method,
+			nameserver,
+			l.uid,
+			l.gid)
+		if err != nil {
+			l.logAndWait(err)
+			continue
+		}
+		err = l.firewallConf.AllowAnyIncomingOnPort(ctx, l.settings.Port)
+		// TODO remove firewall rule on exit below
+		if err != nil {
+			l.logger.Error(err)
+		}
+		shadowsocksCtx, shadowsocksCancel := context.WithCancel(ctx)
+		stdout, stderr, waitFn, err := l.conf.Start(ctx, "0.0.0.0", l.settings.Port, l.settings.Password, l.settings.Log)
+		if err != nil {
+			shadowsocksCancel()
+			l.logAndWait(err)
+			continue
+		}
+		go l.streamMerger.Merge(shadowsocksCtx, stdout,
+			command.MergeName("shadowsocks"), command.MergeColor(constants.ColorShadowsocks()))
+		go l.streamMerger.Merge(shadowsocksCtx, stderr,
+			command.MergeName("shadowsocks error"), command.MergeColor(constants.ColorShadowsocksError()))
+		waitError := make(chan error)
+		go func() {
+			err := waitFn() // blocking
+			if shadowsocksCtx.Err() != context.Canceled {
+				waitError <- err
+			}
+		}()
+		select {
+		case <-ctx.Done():
+			l.logger.Warn("context canceled: exiting loop")
+			shadowsocksCancel()
+			close(waitError)
+			close(done)
+			return
+		case <-restart: // triggered restart
+			l.logger.Info("restarting")
+			shadowsocksCancel()
+			close(waitError)
+		case err := <-waitError: // unexpected error
+			l.logger.Warn(err)
+			l.logger.Info("restarting")
+			shadowsocksCancel()
+			close(waitError)
+			time.Sleep(time.Second)
+		}
+	}
+}