XTLS/Xray-core · error

invalid message length

Error message

invalid message length

What it means

Error "invalid message length" thrown in XTLS/Xray-core.

Source

Thrown at proxy/hysteria/protocol.go:96

// TCPResponse format:
// Status (byte, 0=ok, 1=error)
// Message length (QUIC varint)
// Message (bytes)
// Padding length (QUIC varint)
// Padding (bytes)

func ReadTCPResponse(r io.Reader) (bool, string, error) {
	var status [1]byte
	if _, err := io.ReadFull(r, status[:]); err != nil {
		return false, "", err
	}
	bReader := quicvarint.NewReader(r)
	msgLen, err := quicvarint.Read(bReader)
	if err != nil {
		return false, "", err
	}
	if msgLen > MaxMessageLength {
		return false, "", errors.New("invalid message length")
	}
	var msgBuf []byte
	// No message is fine
	if msgLen > 0 {
		msgBuf = make([]byte, msgLen)
		_, err = io.ReadFull(r, msgBuf)
		if err != nil {
			return false, "", err
		}
	}
	paddingLen, err := quicvarint.Read(bReader)
	if err != nil {
		return false, "", err
	}
	if paddingLen > MaxPaddingLength {
		return false, "", errors.New("invalid padding length")
	}
	if paddingLen > 0 {

View on GitHub (pinned to 7d214f8b09)

When it happens

Trigger: Thrown at proxy/hysteria/protocol.go:96 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of XTLS/Xray-core@7d214f8b09 (2026-08-15). Data as JSON: /api/errors/1dc0bd7c29d6a106. Report an issue: GitHub.