Source: hmac-with-sha256-signature.js

  1. /**
  2.  * This class represents an NDN Data Signature object.
  3.  * Copyright (C) 2016-2018 Regents of the University of California.
  4.  * @author: Jeff Thompson <jefft0@remap.ucla.edu>
  5.  *
  6.  * This program is free software: you can redistribute it and/or modify
  7.  * it under the terms of the GNU Lesser General Public License as published by
  8.  * the Free Software Foundation, either version 3 of the License, or
  9.  * (at your option) any later version.
  10.  *
  11.  * This program is distributed in the hope that it will be useful,
  12.  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14.  * GNU Lesser General Public License for more details.
  15.  *
  16.  * You should have received a copy of the GNU Lesser General Public License
  17.  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18.  * A copy of the GNU Lesser General Public License is in the file COPYING.
  19.  */
  21. /** @ignore */
  22. var Blob = require('./util/blob.js').Blob; /** @ignore */
  23. var ChangeCounter = require('./util/change-counter.js').ChangeCounter; /** @ignore */
  24. var KeyLocator = require('./key-locator.js').KeyLocator;
  26. /**
  27.  * An HmacWithSha256Signature holds the signature bits and other info
  28.  * representing an HmacWithSha256 signature in a packet.
  29.  * Create a new HmacWithSha256Signature object, possibly copying values from
  30.  * another object.
  31.  *
  32.  * @param {HmacWithSha256Signature} value (optional) If value is a
  33.  * HmacWithSha256Signature, copy its values.  If value is omitted, the keyLocator
  34.  * is the default with unspecified values and the signature is unspecified.
  35.  * @constructor
  36.  */
  37. var HmacWithSha256Signature = function HmacWithSha256Signature(value)
  38. {
  39.   if (typeof value === 'object' && value instanceof HmacWithSha256Signature) {
  40.     // Copy the values.
  41.     this.keyLocator_ = new ChangeCounter(new KeyLocator(value.getKeyLocator()));
  42.     this.signature_ = value.signature_;
  43.   }
  44.   else {
  45.     this.keyLocator_ = new ChangeCounter(new KeyLocator());
  46.     this.signature_ = new Blob();
  47.   }
  49.   this.changeCount_ = 0;
  50. };
  52. exports.HmacWithSha256Signature = HmacWithSha256Signature;
  54. /**
  55.  * Create a new HmacWithSha256Signature which is a copy of this object.
  56.  * @return {HmacWithSha256Signature} A new object which is a copy of this object.
  57.  */
  58. HmacWithSha256Signature.prototype.clone = function()
  59. {
  60.   return new HmacWithSha256Signature(this);
  61. };
  63. /**
  64.  * Get the key locator.
  65.  * @return {KeyLocator} The key locator.
  66.  */
  67. HmacWithSha256Signature.prototype.getKeyLocator = function()
  68. {
  69.   return this.keyLocator_.get();
  70. };
  72. /**
  73.  * Get the data packet's signature bytes.
  74.  * @return {Blob} The signature bytes. If not specified, the value isNull().
  75.  */
  76. HmacWithSha256Signature.prototype.getSignature = function()
  77. {
  78.   return this.signature_;
  79. };
  81. /**
  82.  * @deprecated Use getSignature. This method returns a Buffer which is the former
  83.  * behavior of getSignature, and should only be used while updating your code.
  84.  */
  85. HmacWithSha256Signature.prototype.getSignatureAsBuffer = function()
  86. {
  87.   return this.signature_.buf();
  88. };
  90. /**
  91.  * Set the key locator to a copy of the given keyLocator.
  92.  * @param {KeyLocator} keyLocator The KeyLocator to copy.
  93.  */
  94. HmacWithSha256Signature.prototype.setKeyLocator = function(keyLocator)
  95. {
  96.   this.keyLocator_.set(typeof keyLocator === 'object' &&
  97.                        keyLocator instanceof KeyLocator ?
  98.     new KeyLocator(keyLocator) : new KeyLocator());
  99.   ++this.changeCount_;
  100. };
  102. /**
  103.  * Set the data packet's signature bytes.
  104.  * @param {Blob} signature
  105.  */
  106. HmacWithSha256Signature.prototype.setSignature = function(signature)
  107. {
  108.   this.signature_ = typeof signature === 'object' && signature instanceof Blob ?
  109.     signature : new Blob(signature);
  110.   ++this.changeCount_;
  111. };
  113. /**
  114.  * Get the change count, which is incremented each time this object (or a child
  115.  * object) is changed.
  116.  * @return {number} The change count.
  117.  */
  118. HmacWithSha256Signature.prototype.getChangeCount = function()
  119. {
  120.   // Make sure each of the checkChanged is called.
  121.   var changed = this.keyLocator_.checkChanged();
  122.   if (changed)
  123.     // A child object has changed, so update the change count.
  124.     ++this.changeCount_;
  126.   return this.changeCount_;
  127. };
  129. // Define properties so we can change member variable types and implement changeCount_.
  130. Object.defineProperty(HmacWithSha256Signature.prototype, "keyLocator",
  131.   { get: function() { return this.getKeyLocator(); },
  132.     set: function(val) { this.setKeyLocator(val); } });
  133. /**
  134.  * @@deprecated Use getSignature and setSignature.
  135.  */
  136. Object.defineProperty(HmacWithSha256Signature.prototype, "signature",
  137.   { get: function() { return this.getSignatureAsBuffer(); },
  138.     set: function(val) { this.setSignature(val); } });