Direct proxy works

telegram/base.go

@@ -0,0 +1,70 @@
+package telegram
+
+import (
+	"context"
+	"math/rand"
+	"net"
+	"time"
+
+	"github.com/juju/errors"
+
+	"github.com/9seconds/mtg/conntypes"
+	"github.com/9seconds/mtg/utils"
+	"github.com/9seconds/mtg/wrappers"
+)
+
+const telegramDialTimeout = 10 * time.Second
+
+type baseTelegram struct {
+	dialer net.Dialer
+
+	v4DefaultDC conntypes.DC
+	V6DefaultDC conntypes.DC
+	v4Addresses map[conntypes.DC][]string
+	v6Addresses map[conntypes.DC][]string
+}
+
+func (b *baseTelegram) dialToAddress(ctx context.Context,
+	cancel context.CancelFunc,
+	addr string) (wrappers.StreamReadWriteCloser, error) {
+	conn, err := b.dialer.Dial("tcp", addr)
+	if err != nil {
+		return nil, errors.Annotate(err, "Dial has failed")
+	}
+
+	if err := utils.InitTCP(conn); err != nil {
+		return nil, errors.Annotate(err, "Cannot initialize TCP socket")
+	}
+
+	return wrappers.NewTelegramConn(ctx, cancel, conn), nil
+}
+
+func (b *baseTelegram) dial(ctx context.Context,
+	cancel context.CancelFunc,
+	dc conntypes.DC,
+	protocol conntypes.ConnectionProtocol) (wrappers.StreamReadWriteCloser, error) {
+	addr := ""
+
+	switch protocol {
+	case conntypes.ConnectionProtocolIPv4:
+		addr = b.chooseAddress(b.v4Addresses, dc, b.v4DefaultDC)
+	default:
+		addr = b.chooseAddress(b.v6Addresses, dc, b.V6DefaultDC)
+	}
+
+	return b.dialToAddress(ctx, cancel, addr)
+}
+
+func (b *baseTelegram) chooseAddress(addresses map[conntypes.DC][]string,
+	dc, defaultDC conntypes.DC) string {
+	addrs, ok := addresses[dc]
+	if !ok {
+		addrs, _ = addresses[defaultDC]
+	}
+
+	if len(addrs) > 0 {
+		return addrs[rand.Intn(len(addrs))]
+	}
+
+	return ""
+}