opcodes.js

/*
 * Copyright (c) 2021 RethinkDNS and its authors.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2016 Mathias Buus
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

//forked with minor changes from https://github.com/mafintosh/dns-packet

"use strict";

/*
 * Traditional DNS header OPCODEs (4-bits) defined by IANA in
 * https://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml#dns-parameters-5
 */

export function toString(opcode) {
  switch (opcode) {
    case 0:
      return "QUERY";
    case 1:
      return "IQUERY";
    case 2:
      return "STATUS";
    case 3:
      return "OPCODE_3";
    case 4:
      return "NOTIFY";
    case 5:
      return "UPDATE";
    case 6:
      return "OPCODE_6";
    case 7:
      return "OPCODE_7";
    case 8:
      return "OPCODE_8";
    case 9:
      return "OPCODE_9";
    case 10:
      return "OPCODE_10";
    case 11:
      return "OPCODE_11";
    case 12:
      return "OPCODE_12";
    case 13:
      return "OPCODE_13";
    case 14:
      return "OPCODE_14";
    case 15:
      return "OPCODE_15";
  }
  return "OPCODE_" + opcode;
}

export function toOpcode(code) {
  switch (code.toUpperCase()) {
    case "QUERY":
      return 0;
    case "IQUERY":
      return 1;
    case "STATUS":
      return 2;
    case "OPCODE_3":
      return 3;
    case "NOTIFY":
      return 4;
    case "UPDATE":
      return 5;
    case "OPCODE_6":
      return 6;
    case "OPCODE_7":
      return 7;
    case "OPCODE_8":
      return 8;
    case "OPCODE_9":
      return 9;
    case "OPCODE_10":
      return 10;
    case "OPCODE_11":
      return 11;
    case "OPCODE_12":
      return 12;
    case "OPCODE_13":
      return 13;
    case "OPCODE_14":
      return 14;
    case "OPCODE_15":
      return 15;
  }
  return 0;
}