fix: 修复RDP爆破高误报率问题 (#555)

- 移除 screen.go 中错误的认证结果覆盖逻辑
- 启用 NLA 协议的 ErrorCode 字段检测
- 添加 PubKeyAuth 验证确保认证真正成功
- 修复 io.go 中错误被静默忽略的问题
- 修复 socket.go/io.go 中可能导致 panic 的代码
- 修复 screen.go 中文件句柄泄漏和 log.Panic

mylib/grdp/core/io.go

@@ -26,7 +26,10 @@ func ReadBytes(len int, r io.Reader) ([]byte, error) {
 
 func ReadByte(r io.Reader) (byte, error) {
 	b, err := ReadBytes(1, r)
-	return b[0], err
+	if err != nil || len(b) == 0 {
+		return 0, err
+	}
+	return b[0], nil
 }
 
 func ReadUInt8(r io.Reader) (uint8, error) {
@@ -42,7 +45,7 @@ func ReadUint16LE(r io.Reader) (uint16, error) {
 	b := make([]byte, 2)
 	_, err := io.ReadFull(r, b)
 	if err != nil {
-		return 0, nil
+		return 0, err
 	}
 	return binary.LittleEndian.Uint16(b), nil
 }
@@ -51,7 +54,7 @@ func ReadUint16BE(r io.Reader) (uint16, error) {
 	b := make([]byte, 2)
 	_, err := io.ReadFull(r, b)
 	if err != nil {
-		return 0, nil
+		return 0, err
 	}
 	return binary.BigEndian.Uint16(b), nil
 }
@@ -60,7 +63,7 @@ func ReadUInt32LE(r io.Reader) (uint32, error) {
 	b := make([]byte, 4)
 	_, err := io.ReadFull(r, b)
 	if err != nil {
-		return 0, nil
+		return 0, err
 	}
 	return binary.LittleEndian.Uint32(b), nil
 }
@@ -69,7 +72,7 @@ func ReadUInt32BE(r io.Reader) (uint32, error) {
 	b := make([]byte, 4)
 	_, err := io.ReadFull(r, b)
 	if err != nil {
-		return 0, nil
+		return 0, err
 	}
 	return binary.BigEndian.Uint32(b), nil
 }

mylib/grdp/core/socket.go

@@ -69,6 +69,13 @@ func (s *SocketLayer) TlsPubKey() ([]byte, error) {
 	if s.tlsConn == nil {
 		return nil, errors.New("TLS conn does not exist")
 	}
-	pub := s.tlsConn.ConnectionState().PeerCertificates[0].PublicKey.(*rsa.PublicKey)
+	certs := s.tlsConn.ConnectionState().PeerCertificates
+	if len(certs) == 0 {
+		return nil, errors.New("no peer certificates")
+	}
+	pub, ok := certs[0].PublicKey.(*rsa.PublicKey)
+	if !ok {
+		return nil, errors.New("invalid public key type")
+	}
 	return asn1ber.Marshal(*pub)
 }