Bump reva

vendor/github.com/miekg/dns/server.go

@@ -188,6 +188,14 @@ type DecorateReader func(Reader) Reader
 // Implementations should never return a nil Writer.
 type DecorateWriter func(Writer) Writer
 
+// MsgInvalidFunc is a listener hook for observing incoming messages that were discarded
+// because they could not be parsed.
+// Every message that is read by a Reader will eventually be provided to the Handler,
+// rejected (or ignored) by the MsgAcceptFunc, or passed to this function.
+type MsgInvalidFunc func(m []byte, err error)
+
+func DefaultMsgInvalidFunc(m []byte, err error) {}
+
 // A Server defines parameters for running an DNS server.
 type Server struct {
 	// Address to listen on, ":dns" if empty.
@@ -218,6 +226,7 @@ type Server struct {
 	// If NotifyStartedFunc is set it is called once the server has started listening.
 	NotifyStartedFunc func()
 	// DecorateReader is optional, allows customization of the process that reads raw DNS messages.
+	// The decorated reader must not mutate the data read from the conn.
 	DecorateReader DecorateReader
 	// DecorateWriter is optional, allows customization of the process that writes raw DNS messages.
 	DecorateWriter DecorateWriter
@@ -233,6 +242,8 @@ type Server struct {
 	// AcceptMsgFunc will check the incoming message and will reject it early in the process.
 	// By default DefaultMsgAcceptFunc will be used.
 	MsgAcceptFunc MsgAcceptFunc
+	// MsgInvalidFunc is optional, will be called if a message is received but cannot be parsed.
+	MsgInvalidFunc MsgInvalidFunc
 
 	// Shutdown handling
 	lock     sync.RWMutex
@@ -277,6 +288,9 @@ func (srv *Server) init() {
 	if srv.MsgAcceptFunc == nil {
 		srv.MsgAcceptFunc = DefaultMsgAcceptFunc
 	}
+	if srv.MsgInvalidFunc == nil {
+		srv.MsgInvalidFunc = DefaultMsgInvalidFunc
+	}
 	if srv.Handler == nil {
 		srv.Handler = DefaultServeMux
 	}
@@ -318,7 +332,7 @@ func (srv *Server) ListenAndServe() error {
 		return srv.serveTCP(l)
 	case "tcp-tls", "tcp4-tls", "tcp6-tls":
 		if srv.TLSConfig == nil || (len(srv.TLSConfig.Certificates) == 0 && srv.TLSConfig.GetCertificate == nil) {
-			return errors.New("dns: neither Certificates nor GetCertificate set in Config")
+			return errors.New("neither Certificates nor GetCertificate set in config")
 		}
 		network := strings.TrimSuffix(srv.Net, "-tls")
 		l, err := listenTCP(network, addr, srv.ReusePort, srv.ReuseAddr)
@@ -531,6 +545,7 @@ func (srv *Server) serveUDP(l net.PacketConn) error {
 			if cap(m) == srv.UDPSize {
 				srv.udpPool.Put(m[:srv.UDPSize])
 			}
+			srv.MsgInvalidFunc(m, ErrShortRead)
 			continue
 		}
 		wg.Add(1)
@@ -611,6 +626,7 @@ func (srv *Server) serveUDPPacket(wg *sync.WaitGroup, m []byte, u net.PacketConn
 func (srv *Server) serveDNS(m []byte, w *response) {
 	dh, off, err := unpackMsgHdr(m, 0)
 	if err != nil {
+		srv.MsgInvalidFunc(m, err)
 		// Let client hang, they are sending crap; any reply can be used to amplify.
 		return
 	}
@@ -620,10 +636,12 @@ func (srv *Server) serveDNS(m []byte, w *response) {
 
 	switch action := srv.MsgAcceptFunc(dh); action {
 	case MsgAccept:
-		if req.unpack(dh, m, off) == nil {
+		err := req.unpack(dh, m, off)
+		if err == nil {
 			break
 		}
 
+		srv.MsgInvalidFunc(m, err)
 		fallthrough
 	case MsgReject, MsgRejectNotImplemented:
 		opcode := req.Opcode