Add m-esr52 at 52.6.0

1 files changed, 297 insertions, 0 deletions

diff --git a/netwerk/dns/mdns/libmdns/fallback/DNSPacket.jsm b/netwerk/dns/mdns/libmdns/fallback/DNSPacket.jsm
new file mode 100644
index 000000000..f0539fccb
--- /dev/null
+++ b/netwerk/dns/mdns/libmdns/fallback/DNSPacket.jsm
@@ -0,0 +1,297 @@
+/* -*- Mode: js; js-indent-level: 2; indent-tabs-mode: nil; tab-width: 2 -*- */
+/* 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/. */
+/* jshint esnext: true, moz: true */
+
+'use strict';
+
+this.EXPORTED_SYMBOLS = ['DNSPacket'];
+
+const { utils: Cu } = Components;
+
+Cu.import('resource://gre/modules/Services.jsm');
+
+Cu.import('resource://gre/modules/DataReader.jsm');
+Cu.import('resource://gre/modules/DataWriter.jsm');
+Cu.import('resource://gre/modules/DNSRecord.jsm');
+Cu.import('resource://gre/modules/DNSResourceRecord.jsm');
+
+const DEBUG = true;
+
+function debug(msg) {
+  Services.console.logStringMessage('DNSPacket: ' + msg);
+}
+
+let DNS_PACKET_SECTION_TYPES = [
+  'QD', // Question
+  'AN', // Answer
+  'NS', // Authority
+  'AR'  // Additional
+];
+
+/**
+ * DNS Packet Structure
+ * *************************************************
+ *
+ * Header
+ * ======
+ *
+ * 00                   2-Bytes                   15
+ * -------------------------------------------------
+ * |00|01|02|03|04|05|06|07|08|09|10|11|12|13|14|15|
+ * -------------------------------------------------
+ * |<==================== ID =====================>|
+ * |QR|<== OP ===>|AA|TC|RD|RA|UN|AD|CD|<== RC ===>|
+ * |<================== QDCOUNT ==================>|
+ * |<================== ANCOUNT ==================>|
+ * |<================== NSCOUNT ==================>|
+ * |<================== ARCOUNT ==================>|
+ * -------------------------------------------------
+ *
+ * ID:        2-Bytes
+ * FLAGS:     2-Bytes
+ *  - QR:     1-Bit
+ *  - OP:     4-Bits
+ *  - AA:     1-Bit
+ *  - TC:     1-Bit
+ *  - RD:     1-Bit
+ *  - RA:     1-Bit
+ *  - UN:     1-Bit
+ *  - AD:     1-Bit
+ *  - CD:     1-Bit
+ *  - RC:     4-Bits
+ * QDCOUNT:   2-Bytes
+ * ANCOUNT:   2-Bytes
+ * NSCOUNT:   2-Bytes
+ * ARCOUNT:   2-Bytes
+ *
+ *
+ * Data
+ * ====
+ *
+ * 00                   2-Bytes                   15
+ * -------------------------------------------------
+ * |00|01|02|03|04|05|06|07|08|09|10|11|12|13|14|15|
+ * -------------------------------------------------
+ * |<???=============== QD[...] ===============???>|
+ * |<???=============== AN[...] ===============???>|
+ * |<???=============== NS[...] ===============???>|
+ * |<???=============== AR[...] ===============???>|
+ * -------------------------------------------------
+ *
+ * QD:        ??-Bytes
+ * AN:        ??-Bytes
+ * NS:        ??-Bytes
+ * AR:        ??-Bytes
+ *
+ *
+ * Question Record
+ * ===============
+ *
+ * 00                   2-Bytes                   15
+ * -------------------------------------------------
+ * |00|01|02|03|04|05|06|07|08|09|10|11|12|13|14|15|
+ * -------------------------------------------------
+ * |<???================ NAME =================???>|
+ * |<=================== TYPE ====================>|
+ * |<=================== CLASS ===================>|
+ * -------------------------------------------------
+ *
+ * NAME:      ??-Bytes
+ * TYPE:      2-Bytes
+ * CLASS:     2-Bytes
+ *
+ *
+ * Resource Record
+ * ===============
+ *
+ * 00                   4-Bytes                   31
+ * -------------------------------------------------
+ * |00|02|04|06|08|10|12|14|16|18|20|22|24|26|28|30|
+ * -------------------------------------------------
+ * |<???================ NAME =================???>|
+ * |<======= TYPE ========>|<======= CLASS =======>|
+ * |<==================== TTL ====================>|
+ * |<====== DATALEN ======>|<???==== DATA =====???>|
+ * -------------------------------------------------
+ *
+ * NAME:      ??-Bytes
+ * TYPE:      2-Bytes
+ * CLASS:     2-Bytes
+ * DATALEN:   2-Bytes
+ * DATA:      ??-Bytes (Specified By DATALEN)
+ */
+class DNSPacket {
+  constructor() {
+    this._flags = _valueToFlags(0x0000);
+    this._records = {};
+
+    DNS_PACKET_SECTION_TYPES.forEach((sectionType) => {
+      this._records[sectionType] = [];
+    });
+  }
+
+  static parse(data) {
+    let reader = new DataReader(data);
+    if (reader.getValue(2) !== 0x0000) {
+      throw new Error('Packet must start with 0x0000');
+    }
+
+    let packet = new DNSPacket();
+    packet._flags = _valueToFlags(reader.getValue(2));
+
+    let recordCounts = {};
+
+    // Parse the record counts.
+    DNS_PACKET_SECTION_TYPES.forEach((sectionType) => {
+      recordCounts[sectionType] = reader.getValue(2);
+    });
+
+    // Parse the actual records.
+    DNS_PACKET_SECTION_TYPES.forEach((sectionType) => {
+      let recordCount = recordCounts[sectionType];
+      for (let i = 0; i < recordCount; i++) {
+        if (sectionType === 'QD') {
+          packet.addRecord(sectionType,
+              DNSRecord.parseFromPacketReader(reader));
+        }
+
+        else {
+          packet.addRecord(sectionType,
+              DNSResourceRecord.parseFromPacketReader(reader));
+        }
+      }
+    });
+
+    if (!reader.eof) {
+      DEBUG && debug('Did not complete parsing packet data');
+    }
+
+    return packet;
+  }
+
+  getFlag(flag) {
+    return this._flags[flag];
+  }
+
+  setFlag(flag, value) {
+    this._flags[flag] = value;
+  }
+
+  addRecord(sectionType, record) {
+    this._records[sectionType].push(record);
+  }
+
+  getRecords(sectionTypes, recordType) {
+    let records = [];
+
+    sectionTypes.forEach((sectionType) => {
+      records = records.concat(this._records[sectionType]);
+    });
+
+    if (!recordType) {
+      return records;
+    }
+
+    return records.filter(r => r.recordType === recordType);
+  }
+
+  serialize() {
+    let writer = new DataWriter();
+
+    // Write leading 0x0000 (2 bytes)
+    writer.putValue(0x0000, 2);
+
+    // Write `flags` (2 bytes)
+    writer.putValue(_flagsToValue(this._flags), 2);
+
+    // Write lengths of record sections (2 bytes each)
+    DNS_PACKET_SECTION_TYPES.forEach((sectionType) => {
+      writer.putValue(this._records[sectionType].length, 2);
+    });
+
+    // Write records
+    DNS_PACKET_SECTION_TYPES.forEach((sectionType) => {
+      this._records[sectionType].forEach((record) => {
+        writer.putBytes(record.serialize());
+      });
+    });
+
+    return writer.data;
+  }
+
+  toJSON() {
+    return JSON.stringify(this.toJSONObject());
+  }
+
+  toJSONObject() {
+    let result = {flags: this._flags};
+    DNS_PACKET_SECTION_TYPES.forEach((sectionType) => {
+      result[sectionType] = [];
+
+      let records = this._records[sectionType];
+      records.forEach((record) => {
+        result[sectionType].push(record.toJSONObject());
+      });
+    });
+
+    return result;
+  }
+}
+
+/**
+ * @private
+ */
+function _valueToFlags(value) {
+  return {
+    QR: (value & 0x8000) >> 15,
+    OP: (value & 0x7800) >> 11,
+    AA: (value & 0x0400) >> 10,
+    TC: (value & 0x0200) >>  9,
+    RD: (value & 0x0100) >>  8,
+    RA: (value & 0x0080) >>  7,
+    UN: (value & 0x0040) >>  6,
+    AD: (value & 0x0020) >>  5,
+    CD: (value & 0x0010) >>  4,
+    RC: (value & 0x000f) >>  0
+  };
+}
+
+/**
+ * @private
+ */
+function _flagsToValue(flags) {
+  let value = 0x0000;
+
+  value += flags.QR & 0x01;
+
+  value <<= 4;
+  value += flags.OP & 0x0f;
+
+  value <<= 1;
+  value += flags.AA & 0x01;
+
+  value <<= 1;
+  value += flags.TC & 0x01;
+
+  value <<= 1;
+  value += flags.RD & 0x01;
+
+  value <<= 1;
+  value += flags.RA & 0x01;
+
+  value <<= 1;
+  value += flags.UN & 0x01;
+
+  value <<= 1;
+  value += flags.AD & 0x01;
+
+  value <<= 1;
+  value += flags.CD & 0x01;
+
+  value <<= 4;
+  value += flags.RC & 0x0f;
+
+  return value;
+}