Add new API settings

handler/socks.go

@@ -2,14 +2,18 @@ package handler
 
 import (
 	"context"
+	"fmt"
+	"io"
 	"log"
 	"net"
+	"strings"
 
 	"github.com/Alexey71/opera-proxy/dialer"
 	"github.com/things-go/go-socks5"
+	"github.com/things-go/go-socks5/statute"
 )
 
-func NewSocksServer(dialer dialer.ContextDialer, logger *log.Logger) (*socks5.Server, error) {
+func NewSocksServer(dialer dialer.ContextDialer, logger *log.Logger, fakeSNI string) (*socks5.Server, error) {
 	opts := []socks5.Option{
 		socks5.WithLogger(socks5.NewLogger(logger)),
 		socks5.WithRule(
@@ -17,12 +21,45 @@ func NewSocksServer(dialer dialer.ContextDialer, logger *log.Logger) (*socks5.Se
 				EnableConnect: true,
 			},
 		),
-		socks5.WithDial(dialer.DialContext),
 		socks5.WithResolver(DummySocksResolver{}),
+		socks5.WithConnectHandle(func(ctx context.Context, writer io.Writer, request *socks5.Request) error {
+			return handleSocksConnect(ctx, writer, request, dialer, fakeSNI)
+		}),
 	}
 	return socks5.NewServer(opts...), nil
 }
 
+func handleSocksConnect(ctx context.Context, writer io.Writer, request *socks5.Request, upstream dialer.ContextDialer, fakeSNI string) error {
+	target, err := upstream.DialContext(ctx, "tcp", request.DestAddr.String())
+	if err != nil {
+		reply := statute.RepHostUnreachable
+		msg := err.Error()
+		if strings.Contains(msg, "refused") {
+			reply = statute.RepConnectionRefused
+		} else if strings.Contains(msg, "network is unreachable") {
+			reply = statute.RepNetworkUnreachable
+		}
+		if sendErr := socks5.SendReply(writer, reply, nil); sendErr != nil {
+			return fmt.Errorf("failed to send reply, %v", sendErr)
+		}
+		return fmt.Errorf("connect to %v failed, %v", request.RawDestAddr, err)
+	}
+
+	if err := socks5.SendReply(writer, statute.RepSuccess, target.LocalAddr()); err != nil {
+		target.Close()
+		return fmt.Errorf("failed to send reply, %v", err)
+	}
+
+	clientConn, ok := writer.(net.Conn)
+	if !ok {
+		target.Close()
+		return fmt.Errorf("writer is %T, expected net.Conn", writer)
+	}
+
+	proxy(ctx, clientConn, request.Reader, target, fakeSNI)
+	return nil
+}
+
 type DummySocksResolver struct{}
 
 func (_ DummySocksResolver) Resolve(ctx context.Context, name string) (context.Context, net.IP, error) {