add pkgs from core

handler/socks/v5/selector.go

@@ -0,0 +1,90 @@
+package v5
+
+import (
+	"crypto/tls"
+	"net"
+
+	"github.com/go-gost/core/auth"
+	"github.com/go-gost/core/logger"
+	"github.com/go-gost/gosocks5"
+	"github.com/go-gost/x/internal/util/socks"
+)
+
+type serverSelector struct {
+	methods       []uint8
+	Authenticator auth.Authenticator
+	TLSConfig     *tls.Config
+	logger        logger.Logger
+	noTLS         bool
+}
+
+func (selector *serverSelector) Methods() []uint8 {
+	return selector.methods
+}
+
+func (s *serverSelector) Select(methods ...uint8) (method uint8) {
+	s.logger.Debugf("%d %d %v", gosocks5.Ver5, len(methods), methods)
+	method = gosocks5.MethodNoAuth
+	for _, m := range methods {
+		if m == socks.MethodTLS && !s.noTLS {
+			method = m
+			break
+		}
+	}
+
+	// when Authenticator is set, auth is mandatory
+	if s.Authenticator != nil {
+		if method == gosocks5.MethodNoAuth {
+			method = gosocks5.MethodUserPass
+		}
+		if method == socks.MethodTLS && !s.noTLS {
+			method = socks.MethodTLSAuth
+		}
+	}
+
+	return
+}
+
+func (s *serverSelector) OnSelected(method uint8, conn net.Conn) (net.Conn, error) {
+	s.logger.Debugf("%d %d", gosocks5.Ver5, method)
+	switch method {
+	case socks.MethodTLS:
+		conn = tls.Server(conn, s.TLSConfig)
+
+	case gosocks5.MethodUserPass, socks.MethodTLSAuth:
+		if method == socks.MethodTLSAuth {
+			conn = tls.Server(conn, s.TLSConfig)
+		}
+
+		req, err := gosocks5.ReadUserPassRequest(conn)
+		if err != nil {
+			s.logger.Error(err)
+			return nil, err
+		}
+		s.logger.Debug(req)
+
+		if s.Authenticator != nil &&
+			!s.Authenticator.Authenticate(req.Username, req.Password) {
+			resp := gosocks5.NewUserPassResponse(gosocks5.UserPassVer, gosocks5.Failure)
+			if err := resp.Write(conn); err != nil {
+				s.logger.Error(err)
+				return nil, err
+			}
+			s.logger.Info(resp)
+
+			return nil, gosocks5.ErrAuthFailure
+		}
+
+		resp := gosocks5.NewUserPassResponse(gosocks5.UserPassVer, gosocks5.Succeeded)
+		if err := resp.Write(conn); err != nil {
+			s.logger.Error(err)
+			return nil, err
+		}
+		s.logger.Debug(resp)
+
+	case gosocks5.MethodNoAcceptable:
+		return nil, gosocks5.ErrBadMethod
+	}
+
+	return conn, nil
+}