XTLS/Xray-core · error

failed to read addons protobuf value

Error message

failed to read addons protobuf value

What it means

Error "failed to read addons protobuf value" thrown in XTLS/Xray-core.

Source

Thrown at proxy/vless/encoding/addons.go:49

		if err := buffer.WriteByte(0); err != nil {
			return errors.New("failed to write addons protobuf length").Base(err)
		}
	}

	return nil
}

func DecodeHeaderAddons(buffer *buf.Buffer, reader io.Reader) (*Addons, error) {
	addons := new(Addons)
	buffer.Clear()
	if _, err := buffer.ReadFullFrom(reader, 1); err != nil {
		return nil, errors.New("failed to read addons protobuf length").Base(err)
	}

	if length := int32(buffer.Byte(0)); length != 0 {
		buffer.Clear()
		if _, err := buffer.ReadFullFrom(reader, length); err != nil {
			return nil, errors.New("failed to read addons protobuf value").Base(err)
		}

		if err := proto.Unmarshal(buffer.Bytes(), addons); err != nil {
			return nil, errors.New("failed to unmarshal addons protobuf value").Base(err)
		}

		// Verification.
		switch addons.Flow {
		default:
		}
	}

	return addons, nil
}

// EncodeBodyAddons returns a Writer that auto-encrypt content written by caller.
func EncodeBodyAddons(writer buf.Writer, request *protocol.RequestHeader, requestAddons *Addons, state *proxy.TrafficState, isUplink bool, context context.Context, conn net.Conn, ob *session.Outbound) buf.Writer {
	if request.Command == protocol.RequestCommandUDP {

View on GitHub (pinned to 7d214f8b09)

When it happens

Trigger: Thrown at proxy/vless/encoding/addons.go:49 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/d4b325f131c6bbba. Report an issue: GitHub.