mono/mcs/class/System.IdentityModel/System.IdentityModel.Protocols/WSTrust/Entropy.cs

//
// Entropy.cs
//
// Author:
//   Noesis Labs ([email protected])
//
// Copyright (C) 2014 Noesis Labs, LLC  https://noesislabs.com
//
// 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.
//

using System.IdentityModel.Tokens;
using System.Security.Cryptography;

namespace System.IdentityModel.Protocols.WSTrust
{
	public class Entropy : ProtectedKey
	{
		public Entropy (ProtectedKey protectedKey) : base (protectedKey.GetKeyBytes (), protectedKey.WrappingCredentials)
		{ }

		public Entropy (byte[] secret) : base (secret)
		{ }

		public Entropy (int entropySizeInBits)
			: this(Entropy.GetRandomByteArray(entropySizeInBits / 8))
		{ }

		public Entropy (byte[] secret, EncryptingCredentials wrappingCredentials) : base (secret, wrappingCredentials)
		{ }

		private static byte[] GetRandomByteArray (int arraySize) {
			byte[] b = new byte[arraySize];

			RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
			rng.GetNonZeroBytes(b);

			return b;
		}
	}
}