Merge pull request #291 from HyNetwork/domain-passthrough

feat: server SOCKS5 outbound domain passthrough

cmd/server.go

@@ -166,7 +166,10 @@ func server(config *serverConfig) {
 	// ACL
 	var aclEngine *acl.Engine
 	if len(config.ACL) > 0 {
-		aclEngine, err = acl.LoadFromFile(config.ACL, transport.DefaultServerTransport.ResolveIPAddr,
+		aclEngine, err = acl.LoadFromFile(config.ACL, func(addr string) (*net.IPAddr, error) {
+			ipAddr, _, err := transport.DefaultServerTransport.ResolveIPAddr(addr)
+			return ipAddr, err
+		},
 			func() (*geoip2.Reader, error) {
 				if len(config.MMDB) > 0 {
 					return loadMMDBReader(config.MMDB)

pkg/acl/engine.go

@@ -4,6 +4,7 @@ import (
 	"bufio"
 	lru "github.com/hashicorp/golang-lru"
 	"github.com/oschwald/geoip2-golang"
+	"github.com/tobyxdd/hysteria/pkg/utils"
 	"net"
 	"os"
 	"strings"
@@ -64,30 +65,31 @@ func LoadFromFile(filename string, resolveIPAddr func(string) (*net.IPAddr, erro
 	}, nil
 }
 
-func (e *Engine) ResolveAndMatch(host string) (Action, string, *net.IPAddr, error) {
+// action, arg, isDomain, resolvedIP, error
-	ip, zone := parseIPZone(host)
+func (e *Engine) ResolveAndMatch(host string) (Action, string, bool, *net.IPAddr, error) {
+	ip, zone := utils.ParseIPZone(host)
 	if ip == nil {
 		// Domain
 		ipAddr, err := e.ResolveIPAddr(host)
 		if v, ok := e.Cache.Get(host); ok {
 			// Cache hit
 			ce := v.(cacheEntry)
-			return ce.Action, ce.Arg, ipAddr, err
+			return ce.Action, ce.Arg, true, ipAddr, err
 		}
 		for _, entry := range e.Entries {
 			if entry.MatchDomain(host) || (ipAddr != nil && entry.MatchIP(ipAddr.IP, e.GeoIPReader)) {
 				e.Cache.Add(host, cacheEntry{entry.Action, entry.ActionArg})
-				return entry.Action, entry.ActionArg, ipAddr, err
+				return entry.Action, entry.ActionArg, true, ipAddr, err
 			}
 		}
 		e.Cache.Add(host, cacheEntry{e.DefaultAction, ""})
-		return e.DefaultAction, "", ipAddr, err
+		return e.DefaultAction, "", true, ipAddr, err
 	} else {
 		// IP
 		if v, ok := e.Cache.Get(ip.String()); ok {
 			// Cache hit
 			ce := v.(cacheEntry)
-			return ce.Action, ce.Arg, &net.IPAddr{
+			return ce.Action, ce.Arg, false, &net.IPAddr{
 				IP:   ip,
 				Zone: zone,
 			}, nil
@@ -95,14 +97,14 @@ func (e *Engine) ResolveAndMatch(host string) (Action, string, *net.IPAddr, erro
 		for _, entry := range e.Entries {
 			if entry.MatchIP(ip, e.GeoIPReader) {
 				e.Cache.Add(ip.String(), cacheEntry{entry.Action, entry.ActionArg})
-				return entry.Action, entry.ActionArg, &net.IPAddr{
+				return entry.Action, entry.ActionArg, false, &net.IPAddr{
 					IP:   ip,
 					Zone: zone,
 				}, nil
 			}
 		}
 		e.Cache.Add(ip.String(), cacheEntry{e.DefaultAction, ""})
-		return e.DefaultAction, "", &net.IPAddr{
+		return e.DefaultAction, "", false, &net.IPAddr{
 			IP:   ip,
 			Zone: zone,
 		}, nil

pkg/acl/ip.go

@@ -1,27 +0,0 @@
-package acl
-
-import "net"
-
-func parseIPZone(s string) (net.IP, string) {
-	s, zone := splitHostZone(s)
-	return net.ParseIP(s), zone
-}
-
-func splitHostZone(s string) (host, zone string) {
-	if i := last(s, '%'); i > 0 {
-		host, zone = s[:i], s[i+1:]
-	} else {
-		host = s
-	}
-	return
-}
-
-func last(s string, b byte) int {
-	i := len(s)
-	for i--; i >= 0; i-- {
-		if s[i] == b {
-			break
-		}
-	}
-	return i
-}

pkg/core/server_client.go

@@ -154,36 +154,43 @@ func (c *serverClient) handleMessage(msg []byte) {
 	if ok {
 		// Session found, send the message
 		action, arg := acl.ActionDirect, ""
+		var isDomain bool
 		var ipAddr *net.IPAddr
 		var err error
 		if c.ACLEngine != nil {
-			action, arg, ipAddr, err = c.ACLEngine.ResolveAndMatch(dfMsg.Host)
+			action, arg, isDomain, ipAddr, err = c.ACLEngine.ResolveAndMatch(dfMsg.Host)
 		} else {
-			ipAddr, err = c.Transport.ResolveIPAddr(dfMsg.Host)
+			ipAddr, isDomain, err = c.Transport.ResolveIPAddr(dfMsg.Host)
 		}
-		if err != nil {
+		if err != nil && !(isDomain && c.Transport.SOCKS5Enabled()) { // Special case for domain requests + SOCKS5 outbound
 			return
 		}
 		switch action {
 		case acl.ActionDirect, acl.ActionProxy: // Treat proxy as direct on server side
-			_, _ = conn.WriteToUDP(dfMsg.Data, &net.UDPAddr{
+			addrEx := &transport.AddrEx{
-				IP:   ipAddr.IP,
+				IPAddr: ipAddr,
-				Port: int(dfMsg.Port),
+				Port:   int(dfMsg.Port),
-				Zone: ipAddr.Zone,
+			}
-			})
+			if isDomain {
+				addrEx.Domain = dfMsg.Host
+			}
+			_, _ = conn.WriteToUDP(dfMsg.Data, addrEx)
 			if c.UpCounter != nil {
 				c.UpCounter.Add(float64(len(dfMsg.Data)))
 			}
 		case acl.ActionBlock:
 			// Do nothing
 		case acl.ActionHijack:
-			hijackIPAddr, err := c.Transport.ResolveIPAddr(arg)
+			hijackIPAddr, isDomain, err := c.Transport.ResolveIPAddr(arg)
-			if err == nil {
+			if err == nil || (isDomain && c.Transport.SOCKS5Enabled()) { // Special case for domain requests + SOCKS5 outbound
-				_, _ = conn.WriteToUDP(dfMsg.Data, &net.UDPAddr{
+				addrEx := &transport.AddrEx{
-					IP:   hijackIPAddr.IP,
+					IPAddr: hijackIPAddr,
-					Port: int(dfMsg.Port),
+					Port:   int(dfMsg.Port),
-					Zone: hijackIPAddr.Zone,
+				}
-				})
+				if isDomain {
+					addrEx.Domain = arg
+				}
+				_, _ = conn.WriteToUDP(dfMsg.Data, addrEx)
 				if c.UpCounter != nil {
 					c.UpCounter.Add(float64(len(dfMsg.Data)))
 				}
@@ -197,14 +204,15 @@ func (c *serverClient) handleMessage(msg []byte) {
 func (c *serverClient) handleTCP(stream quic.Stream, host string, port uint16) {
 	addrStr := net.JoinHostPort(host, strconv.Itoa(int(port)))
 	action, arg := acl.ActionDirect, ""
+	var isDomain bool
 	var ipAddr *net.IPAddr
 	var err error
 	if c.ACLEngine != nil {
-		action, arg, ipAddr, err = c.ACLEngine.ResolveAndMatch(host)
+		action, arg, isDomain, ipAddr, err = c.ACLEngine.ResolveAndMatch(host)
 	} else {
-		ipAddr, err = c.Transport.ResolveIPAddr(host)
+		ipAddr, isDomain, err = c.Transport.ResolveIPAddr(host)
 	}
-	if err != nil {
+	if err != nil && !(isDomain && c.Transport.SOCKS5Enabled()) { // Special case for domain requests + SOCKS5 outbound
 		_ = struc.Pack(stream, &serverResponse{
 			OK:      false,
 			Message: "host resolution failure",
@@ -217,11 +225,14 @@ func (c *serverClient) handleTCP(stream quic.Stream, host string, port uint16) {
 	var conn net.Conn // Connection to be piped
 	switch action {
 	case acl.ActionDirect, acl.ActionProxy: // Treat proxy as direct on server side
-		conn, err = c.Transport.DialTCP(&net.TCPAddr{
+		addrEx := &transport.AddrEx{
-			IP:   ipAddr.IP,
+			IPAddr: ipAddr,
-			Port: int(port),
+			Port:   int(port),
-			Zone: ipAddr.Zone,
+		}
-		})
+		if isDomain {
+			addrEx.Domain = host
+		}
+		conn, err = c.Transport.DialTCP(addrEx)
 		if err != nil {
 			_ = struc.Pack(stream, &serverResponse{
 				OK:      false,
@@ -237,8 +248,8 @@ func (c *serverClient) handleTCP(stream quic.Stream, host string, port uint16) {
 		})
 		return
 	case acl.ActionHijack:
-		hijackIPAddr, err := c.Transport.ResolveIPAddr(arg)
+		hijackIPAddr, isDomain, err := c.Transport.ResolveIPAddr(arg)
-		if err != nil {
+		if err != nil && !(isDomain && c.Transport.SOCKS5Enabled()) { // Special case for domain requests + SOCKS5 outbound
 			_ = struc.Pack(stream, &serverResponse{
 				OK:      false,
 				Message: err.Error(),
@@ -246,11 +257,14 @@ func (c *serverClient) handleTCP(stream quic.Stream, host string, port uint16) {
 			c.CTCPErrorFunc(c.ClientAddr, c.Auth, addrStr, err)
 			return
 		}
-		conn, err = c.Transport.DialTCP(&net.TCPAddr{
+		addrEx := &transport.AddrEx{
-			IP:   hijackIPAddr.IP,
+			IPAddr: hijackIPAddr,
-			Port: int(port),
+			Port:   int(port),
-			Zone: hijackIPAddr.Zone,
+		}
-		})
+		if isDomain {
+			addrEx.Domain = arg
+		}
+		conn, err = c.Transport.DialTCP(addrEx)
 		if err != nil {
 			_ = struc.Pack(stream, &serverResponse{
 				OK:      false,

pkg/http/server.go

@@ -34,7 +34,7 @@ func NewProxyHTTPServer(hyClient *core.Client, transport *transport.ClientTransp
 			var ipAddr *net.IPAddr
 			var resErr error
 			if aclEngine != nil {
-				action, arg, ipAddr, resErr = aclEngine.ResolveAndMatch(host)
+				action, arg, _, ipAddr, resErr = aclEngine.ResolveAndMatch(host)
 				// Doesn't always matter if the resolution fails, as we may send it through HyClient
 			}
 			newDialFunc(addr, action, arg)

pkg/socks5/server.go

@@ -171,7 +171,7 @@ func (s *Server) handleTCP(c *net.TCPConn, r *socks5.Request) error {
 	var ipAddr *net.IPAddr
 	var resErr error
 	if s.ACLEngine != nil {
-		action, arg, ipAddr, resErr = s.ACLEngine.ResolveAndMatch(host)
+		action, arg, _, ipAddr, resErr = s.ACLEngine.ResolveAndMatch(host)
 		// Doesn't always matter if the resolution fails, as we may send it through HyClient
 	}
 	s.TCPRequestFunc(c.RemoteAddr(), addr, action, arg)
@@ -377,7 +377,7 @@ func (s *Server) udpServer(clientConn *net.UDPConn, localRelayConn *net.UDPConn,
 		var ipAddr *net.IPAddr
 		var resErr error
 		if s.ACLEngine != nil && localRelayConn != nil {
-			action, arg, ipAddr, resErr = s.ACLEngine.ResolveAndMatch(host)
+			action, arg, _, ipAddr, resErr = s.ACLEngine.ResolveAndMatch(host)
 			// Doesn't always matter if the resolution fails, as we may send it through HyClient
 		}
 		// Handle according to the action

pkg/transport/server.go

@@ -8,7 +8,9 @@ import (
 	"github.com/tobyxdd/hysteria/pkg/conns/udp"
 	"github.com/tobyxdd/hysteria/pkg/conns/wechat"
 	"github.com/tobyxdd/hysteria/pkg/obfs"
+	"github.com/tobyxdd/hysteria/pkg/utils"
 	"net"
+	"strconv"
 	"time"
 )
 
@@ -20,12 +22,51 @@ type ServerTransport struct {
 	PrefExclusive bool
 }
 
+// AddrEx is like net.TCPAddr or net.UDPAddr, but with additional domain information for SOCKS5.
+// At least one of Domain and IPAddr must be non-empty.
+type AddrEx struct {
+	Domain string
+	IPAddr *net.IPAddr
+	Port   int
+}
+
+func (a *AddrEx) String() string {
+	if a == nil {
+		return "<nil>"
+	}
+	var ip string
+	if a.IPAddr != nil {
+		ip = a.IPAddr.String()
+	}
+	return net.JoinHostPort(ip, strconv.Itoa(a.Port))
+}
+
 type PUDPConn interface {
 	ReadFromUDP([]byte) (int, *net.UDPAddr, error)
-	WriteToUDP([]byte, *net.UDPAddr) (int, error)
+	WriteToUDP([]byte, *AddrEx) (int, error)
 	Close() error
 }
 
+type udpConnPUDPConn struct {
+	Conn *net.UDPConn
+}
+
+func (c *udpConnPUDPConn) ReadFromUDP(bytes []byte) (int, *net.UDPAddr, error) {
+	return c.Conn.ReadFromUDP(bytes)
+}
+
+func (c *udpConnPUDPConn) WriteToUDP(bytes []byte, ex *AddrEx) (int, error) {
+	return c.Conn.WriteToUDP(bytes, &net.UDPAddr{
+		IP:   ex.IPAddr.IP,
+		Port: ex.Port,
+		Zone: ex.IPAddr.Zone,
+	})
+}
+
+func (c *udpConnPUDPConn) Close() error {
+	return c.Conn.Close()
+}
+
 var DefaultServerTransport = &ServerTransport{
 	Dialer: &net.Dialer{
 		Timeout: 8 * time.Second,
@@ -80,8 +121,8 @@ func (st *ServerTransport) quicPacketConn(proto string, laddr string, obfs obfs.
 	}
 }
 
-func (ct *ServerTransport) QUICListen(proto string, listen string, tlsConfig *tls.Config, quicConfig *quic.Config, obfs obfs.Obfuscator) (quic.Listener, error) {
+func (st *ServerTransport) QUICListen(proto string, listen string, tlsConfig *tls.Config, quicConfig *quic.Config, obfs obfs.Obfuscator) (quic.Listener, error) {
-	pktConn, err := ct.quicPacketConn(proto, listen, obfs)
+	pktConn, err := st.quicPacketConn(proto, listen, obfs)
 	if err != nil {
 		return nil, err
 	}
@@ -93,19 +134,25 @@ func (ct *ServerTransport) QUICListen(proto string, listen string, tlsConfig *tl
 	return l, nil
 }
 
-func (ct *ServerTransport) ResolveIPAddr(address string) (*net.IPAddr, error) {
+func (st *ServerTransport) ResolveIPAddr(address string) (*net.IPAddr, bool, error) {
-	if ct.PrefEnabled {
+	ip, zone := utils.ParseIPZone(address)
-		return resolveIPAddrWithPreference(address, ct.PrefIPv6, ct.PrefExclusive)
+	if ip != nil {
+		return &net.IPAddr{IP: ip, Zone: zone}, false, nil
+	}
+	if st.PrefEnabled {
+		ipAddr, err := resolveIPAddrWithPreference(address, st.PrefIPv6, st.PrefExclusive)
+		return ipAddr, true, err
 	} else {
-		return net.ResolveIPAddr("ip", address)
+		ipAddr, err := net.ResolveIPAddr("ip", address)
+		return ipAddr, true, err
 	}
 }
 
-func (ct *ServerTransport) DialTCP(raddr *net.TCPAddr) (*net.TCPConn, error) {
+func (st *ServerTransport) DialTCP(raddr *AddrEx) (*net.TCPConn, error) {
-	if ct.SOCKS5Client != nil {
+	if st.SOCKS5Client != nil {
-		return ct.SOCKS5Client.DialTCP(raddr)
+		return st.SOCKS5Client.DialTCP(raddr)
 	} else {
-		conn, err := ct.Dialer.Dial("tcp", raddr.String())
+		conn, err := st.Dialer.Dial("tcp", raddr.String())
 		if err != nil {
 			return nil, err
 		}
@@ -113,10 +160,20 @@ func (ct *ServerTransport) DialTCP(raddr *net.TCPAddr) (*net.TCPConn, error) {
 	}
 }
 
-func (ct *ServerTransport) ListenUDP() (PUDPConn, error) {
+func (st *ServerTransport) ListenUDP() (PUDPConn, error) {
-	if ct.SOCKS5Client != nil {
+	if st.SOCKS5Client != nil {
-		return ct.SOCKS5Client.ListenUDP()
+		return st.SOCKS5Client.ListenUDP()
 	} else {
-		return net.ListenUDP("udp", nil)
+		conn, err := net.ListenUDP("udp", nil)
+		if err != nil {
+			return nil, err
+		}
+		return &udpConnPUDPConn{
+			Conn: conn,
+		}, nil
 	}
 }
+
+func (st *ServerTransport) SOCKS5Enabled() bool {
+	return st.SOCKS5Client != nil
+}

pkg/transport/socks5.go

@@ -73,7 +73,7 @@ func (c *SOCKS5Client) request(conn *net.TCPConn, r *socks5.Request) (*socks5.Re
 	return reply, nil
 }
 
-func (c *SOCKS5Client) DialTCP(raddr *net.TCPAddr) (*net.TCPConn, error) {
+func (c *SOCKS5Client) DialTCP(raddr *AddrEx) (*net.TCPConn, error) {
 	conn, err := net.DialTCP("tcp", nil, c.ServerTCPAddr)
 	if err != nil {
 		return nil, err
@@ -87,7 +87,7 @@ func (c *SOCKS5Client) DialTCP(raddr *net.TCPAddr) (*net.TCPConn, error) {
 		_ = conn.Close()
 		return nil, err
 	}
-	atyp, addr, port, err := addrToSOCKS5Addr(raddr)
+	atyp, addr, port, err := addrExToSOCKS5Addr(raddr)
 	if err != nil {
 		_ = conn.Close()
 		return nil, err
@@ -191,8 +191,8 @@ func (c *socks5UDPConn) ReadFromUDP(b []byte) (int, *net.UDPAddr, error) {
 	return n, addr, nil
 }
 
-func (c *socks5UDPConn) WriteToUDP(b []byte, addr *net.UDPAddr) (int, error) {
+func (c *socks5UDPConn) WriteToUDP(b []byte, addr *AddrEx) (int, error) {
-	atyp, dstAddr, dstPort, err := addrToSOCKS5Addr(addr)
+	atyp, dstAddr, dstPort, err := addrExToSOCKS5Addr(addr)
 	if err != nil {
 		return 0, err
 	}
@@ -247,30 +247,23 @@ func socks5AddrToUDPAddr(atyp byte, addr []byte, port []byte) (*net.UDPAddr, err
 	}
 }
 
-func addrToSOCKS5Addr(addr net.Addr) (byte, []byte, []byte, error) {
+func addrExToSOCKS5Addr(addr *AddrEx) (byte, []byte, []byte, error) {
-	var addrIP net.IP
+	sport := make([]byte, 2)
-	var addrPort int
+	binary.BigEndian.PutUint16(sport, uint16(addr.Port))
-	if tcpAddr, ok := addr.(*net.TCPAddr); ok {
+	if len(addr.Domain) > 0 {
-		addrIP = tcpAddr.IP
+		return socks5.ATYPDomain, []byte(addr.Domain), sport, nil
-		addrPort = tcpAddr.Port
-	} else if udpAddr, ok := addr.(*net.UDPAddr); ok {
-		addrIP = udpAddr.IP
-		addrPort = udpAddr.Port
 	} else {
-		return 0, nil, nil, errors.New("unsupported address type")
+		var atyp byte
+		var saddr []byte
+		if ip4 := addr.IPAddr.IP.To4(); ip4 != nil {
+			atyp = socks5.ATYPIPv4
+			saddr = ip4
+		} else if ip6 := addr.IPAddr.IP.To16(); ip6 != nil {
+			atyp = socks5.ATYPIPv6
+			saddr = ip6
+		} else {
+			return 0, nil, nil, errors.New("unsupported address type")
+		}
+		return atyp, saddr, sport, nil
 	}
-	var atyp byte
-	var saddr, sport []byte
-	if ip4 := addrIP.To4(); ip4 != nil {
-		atyp = socks5.ATYPIPv4
-		saddr = ip4
-	} else if ip6 := addrIP.To16(); ip6 != nil {
-		atyp = socks5.ATYPIPv6
-		saddr = ip6
-	} else {
-		return 0, nil, nil, errors.New("unsupported address type")
-	}
-	sport = make([]byte, 2)
-	binary.BigEndian.PutUint16(sport, uint16(addrPort))
-	return atyp, saddr, sport, nil
 }

pkg/utils/misc.go

@@ -16,3 +16,27 @@ func SplitHostPort(hostport string) (string, uint16, error) {
 	}
 	return host, uint16(portUint), err
 }
+
+func ParseIPZone(s string) (net.IP, string) {
+	s, zone := splitHostZone(s)
+	return net.ParseIP(s), zone
+}
+
+func splitHostZone(s string) (host, zone string) {
+	if i := last(s, '%'); i > 0 {
+		host, zone = s[:i], s[i+1:]
+	} else {
+		host = s
+	}
+	return
+}
+
+func last(s string, b byte) int {
+	i := len(s)
+	for i--; i >= 0; i-- {
+		if s[i] == b {
+			break
+		}
+	}
+	return i
+}