fix(recv): panic on short data len

gold/link/listen.go

@@ -130,6 +130,12 @@ func (m *Me) listen() (conn p2p.Conn, err error) {
 				}
 				continue
 			}
+			if n <= 0 {
+				if config.ShowDebugLog {
+					logrus.Debugln("[listen] unexpected read n =", n)
+				}
+				continue
+			}
 			lq := lstnq{
 				index: -1,
 				addr:  addr,

gold/link/recv.go

@@ -32,8 +32,19 @@ func (m *Me) wait(data []byte) *head.Packet {
 	}
 	if m.base14 {
 		data = base14.Decode(data)
+		if len(data) < bound {
+			bound = len(data)
+			endl = "."
+		}
+		if config.ShowDebugLog {
+			logrus.Debugln("[recv] data b14ed", hex.EncodeToString(data[:bound]), endl)
+		}
 	}
 	seq, data := m.xordec(data)
+	if len(data) < bound {
+		bound = len(data)
+		endl = "."
+	}
 	if config.ShowDebugLog {
 		logrus.Debugln("[recv] data xored", hex.EncodeToString(data[:bound]), endl)
 	}

gold/p2p/tcp/pdu.go

@@ -63,6 +63,9 @@ func (p *packet) ReadFrom(r io.Reader) (n int64, err error) {
 	}
 	if binary.LittleEndian.Uint32(buf[:]) != magic {
 		err = ErrInvalidMagic
+		if config.ShowDebugLog {
+			logrus.Debugf("[tcp] expect magic %08x but got %08x", magic, binary.LittleEndian.Uint32(buf[:]))
+		}
 		return
 	}
 	cnt, err = io.ReadFull(r, buf[:3])

gold/p2p/tcp/tcp.go

@@ -258,7 +258,10 @@ func (conn *Conn) receive(tcpconn *net.TCPConn, hasvalidated bool) {
 			if config.ShowDebugLog {
 				logrus.Debugln("[tcp] recv from", ep, "err:", err)
 			}
-			if errors.Is(err, net.ErrClosed) || errors.Is(err, io.ErrClosedPipe) || errors.Is(err, io.EOF) {
+			if errors.Is(err, net.ErrClosed) ||
+				errors.Is(err, io.ErrClosedPipe) ||
+				errors.Is(err, io.EOF) ||
+				errors.Is(err, ErrInvalidMagic) {
 				_ = tcpconn.CloseRead()
 				return
 			}