Improve connection timeout

common/dialer/tls.go

@@ -0,0 +1,86 @@
+package dialer
+
+import (
+	"context"
+	"crypto/tls"
+	"crypto/x509"
+	"net"
+	"net/netip"
+	"os"
+
+	C "github.com/sagernet/sing-box/constant"
+	"github.com/sagernet/sing-box/option"
+	E "github.com/sagernet/sing/common/exceptions"
+	M "github.com/sagernet/sing/common/metadata"
+	N "github.com/sagernet/sing/common/network"
+)
+
+type TLSDialer struct {
+	dialer N.Dialer
+	config *tls.Config
+}
+
+func NewTLS(dialer N.Dialer, serverAddress string, options option.OutboundTLSOptions) (N.Dialer, error) {
+	if !options.Enabled {
+		return dialer, nil
+	}
+
+	var serverName string
+	if options.ServerName != "" {
+		serverName = options.ServerName
+	} else if serverAddress != "" {
+		if _, err := netip.ParseAddr(serverName); err != nil {
+			serverName = serverAddress
+		}
+	}
+	if serverName == "" && options.Insecure {
+		return nil, E.New("missing server_name or insecure=true")
+	}
+
+	var tlsConfig tls.Config
+	if options.DisableSNI {
+		tlsConfig.ServerName = "127.0.0.1"
+	} else {
+		tlsConfig.ServerName = serverName
+	}
+	if options.Insecure {
+		tlsConfig.InsecureSkipVerify = options.Insecure
+	} else if options.DisableSNI {
+		tlsConfig.InsecureSkipVerify = true
+		tlsConfig.VerifyConnection = func(state tls.ConnectionState) error {
+			verifyOptions := x509.VerifyOptions{
+				DNSName:       serverName,
+				Intermediates: x509.NewCertPool(),
+			}
+			for _, cert := range state.PeerCertificates[1:] {
+				verifyOptions.Intermediates.AddCert(cert)
+			}
+			_, err := state.PeerCertificates[0].Verify(verifyOptions)
+			return err
+		}
+	}
+
+	return &TLSDialer{
+		dialer: dialer,
+		config: &tlsConfig,
+	}, nil
+}
+
+func (d *TLSDialer) DialContext(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error) {
+	if network != C.NetworkTCP {
+		return nil, os.ErrInvalid
+	}
+	conn, err := d.dialer.DialContext(ctx, network, destination)
+	if err != nil {
+		return nil, err
+	}
+	tlsConn := tls.Client(conn, d.config)
+	ctx, cancel := context.WithTimeout(context.Background(), C.DefaultTCPTimeout)
+	defer cancel()
+	err = tlsConn.HandshakeContext(ctx)
+	return tlsConn, err
+}
+
+func (d *TLSDialer) ListenPacket(ctx context.Context, destination M.Socksaddr) (net.PacketConn, error) {
+	return nil, os.ErrInvalid
+}