From d8b1e3359a405f4282f8a4df9f5d20debd5d44fa Mon Sep 17 00:00:00 2001
From: Ismael Bejarano <ismael.bejarano@coinfabrik.com>
Date: Fri, 12 Aug 2016 00:22:59 -0300
Subject: [PATCH] Result of wrapping a session key for ECDH key

---
 src/index.js            |  6 ++++
 src/type/ecdh_symkey.js | 71 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 77 insertions(+)
 create mode 100644 src/type/ecdh_symkey.js

diff --git a/src/index.js b/src/index.js
index 64c95c8c..e701837b 100644
--- a/src/index.js
+++ b/src/index.js
@@ -77,6 +77,12 @@ export { default as S2K } from './type/s2k';
  */
 export { default as Keyid } from './type/keyid';
 
+/**
+ * @see module:type/ecdh_symkey
+ * @name module:openpgp.EcdhSymmetricKey
+ */
+export { default as EcdhSymmetricKey } from './type/ecdh_symkey';
+
 /**
  * @see module:type/oid
  * @name module:openpgp.Oid
diff --git a/src/type/ecdh_symkey.js b/src/type/ecdh_symkey.js
new file mode 100644
index 00000000..ef32b68a
--- /dev/null
+++ b/src/type/ecdh_symkey.js
@@ -0,0 +1,71 @@
+// OpenPGP.js - An OpenPGP implementation in javascript
+// Copyright (C) 2015-2016 Decentral
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 3.0 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+/**
+ * Encoded symmetric key for ECDH<br/>
+ * <br/>
+ * @requires util
+ * @module type/ecdh_symkey
+ */
+
+'use strict';
+
+import util from '../util.js';
+
+module.exports = EcdhSymmetricKey;
+
+/**
+ * @constructor
+ */
+function EcdhSymmetricKey(data) {
+  if (typeof data === 'undefined') {
+    data = new Uint8Array([]);
+  } else if (typeof data === 'string') {
+    data = util.str2Uint8Array(data);
+  } else {
+    data = new Uint8Array(data);
+  }
+  this.data = data;
+}
+
+/**
+ * Read an EcdhSymmetricKey from an Uint8Array
+ * @param  {Uint8Array}  input  Where to read the encoded symmetric key from
+ * @return {Number}             Number of read bytes
+ */
+EcdhSymmetricKey.prototype.read = function (input) {
+  if (input.length >= 1)
+  {
+    var length = input[0];
+    if (input.length >= 1+length)
+    {
+      this.data = input.subarray(1, 1+length);
+      return 1+this.data.length;
+    }
+  }
+  throw new Error('Invalid symmetric key');
+};
+
+/**
+ * Write an EcdhSymmetricKey as an Uint8Array
+ * @return  {Uint8Array}  An array containing the value
+ */
+EcdhSymmetricKey.prototype.write = function () {
+  return util.concatUint8Array([
+    new Uint8Array([this.data.length]),
+    this.data]);
+};