public void DecryptKey_Context()
        {
            var mock = new Mock <IDataKeyProvider>();

            var context = new Dictionary <string, string>();

            context["multiplier"] = "3";

            int decryptions = 0;

            mock.Setup(x => x.DecryptKey(It.IsAny <byte[]>()))
            .Returns((byte[] input) => input.Select(x => (byte)(x * 2)).ToArray())
            .Callback(() => decryptions++);

            mock.Setup(x => x.DecryptKey(It.IsAny <byte[]>(), It.IsAny <IDictionary <string, string> >()))
            .Returns((byte[] input, IDictionary <string, string> ctx) =>
            {
                var multiplier = int.Parse(context["multiplier"]);
                return(input.Select(x => (byte)(x * multiplier)).ToArray());
            })
            .Callback(() => decryptions++);

            var provider = new CachingDataKeyProvider(mock.Object, 2);

            provider.DecryptKey(Bytes(1, 2, 3)).Should().Equal(Bytes(2, 4, 6));
            decryptions.Should().Be(1);

            context["multiplier"] = "3";
            provider.DecryptKey(Bytes(1, 2, 3), context).Should().Equal(Bytes(3, 6, 9));
            decryptions.Should().Be(2);

            provider.DecryptKey(Bytes(1, 2, 3)).Should().Equal(Bytes(2, 4, 6));
            decryptions.Should().Be(2);             // still

            context["multiplier"] = "3";
            provider.DecryptKey(Bytes(1, 2, 3), context).Should().Equal(Bytes(3, 6, 9));
            decryptions.Should().Be(2);             // still

            context["multiplier"] = "3";
            provider.DecryptKey(Bytes(1, 2, 3), context).Should().Equal(Bytes(3, 6, 9));
            decryptions.Should().Be(2);             // still

            provider.DecryptKey(Bytes(1, 2, 3)).Should().Equal(Bytes(2, 4, 6));
            decryptions.Should().Be(2);             // still

            context["multiplier"] = "0";
            provider.DecryptKey(Bytes(1, 2, 3), context).Should().Equal(Bytes(0, 0, 0));
            decryptions.Should().Be(3);

            provider.DecryptKey(Bytes(1, 2, 3)).Should().Equal(Bytes(2, 4, 6));
            decryptions.Should().Be(3);             // still

            context["multiplier"] = "3";
            provider.DecryptKey(Bytes(1, 2, 3), context).Should().Equal(Bytes(3, 6, 9));
            decryptions.Should().Be(4);

            context["multiplier"] = "4";
            provider.DecryptKey(Bytes(1, 2, 3), context).Should().Equal(Bytes(4, 8, 12));
            decryptions.Should().Be(5);
        }
        public void DecryptKey()
        {
            var mock = new Mock <IDataKeyProvider>();

            int decryptions = 0;

            mock.Setup(x => x.DecryptKey(It.IsAny <byte[]>()))
            .Returns((byte[] input) => input.Select(x => (byte)(x * 2)).ToArray())
            .Callback(() => decryptions++);

            var provider = new CachingDataKeyProvider(mock.Object, 2);

            provider.DecryptKey(Bytes(1, 2, 3)).Should().Equal(Bytes(2, 4, 6));
            decryptions.Should().Be(1);
            provider.DecryptKey(Bytes(1, 2, 3)).Should().Equal(Bytes(2, 4, 6));
            decryptions.Should().Be(1);                 // still
            provider.DecryptKey(Bytes(1, 2, 3)).Should().Equal(Bytes(2, 4, 6));
            decryptions.Should().Be(1);                 // still

            // changed the key... this one won't be cached
            provider.DecryptKey(Bytes(2, 3, 4)).Should().Equal(Bytes(4, 6, 8));
            decryptions.Should().Be(2);

            // cache is now full
            provider.DecryptKey(Bytes(3, 4, 5)).Should().Equal(Bytes(6, 8, 10));
            decryptions.Should().Be(3);
            provider.DecryptKey(Bytes(2, 3, 4)).Should().Equal(Bytes(4, 6, 8));
            decryptions.Should().Be(3);             // still

            // first one fell out of the cache, so it will cause another decrypt
            provider.DecryptKey(Bytes(1, 2, 3)).Should().Equal(Bytes(2, 4, 6));
            decryptions.Should().Be(4);
        }
		public void DecryptKey()
		{
			var mock = new Mock<IDataKeyProvider>();

			int decryptions = 0;
			mock.Setup(x => x.DecryptKey(It.IsAny<byte[]>()))
				.Returns((byte[] input) => input.Select(x => (byte)(x * 2)).ToArray())
				.Callback(() => decryptions++);

			var provider = new CachingDataKeyProvider(mock.Object, 2); 

			provider.DecryptKey(Bytes(1,2,3)).Should().Equal(Bytes(2,4,6));
			decryptions.Should().Be(1);
			provider.DecryptKey(Bytes(1,2,3)).Should().Equal(Bytes(2,4,6));
			decryptions.Should().Be(1);	// still
			provider.DecryptKey(Bytes(1,2,3)).Should().Equal(Bytes(2,4,6));
			decryptions.Should().Be(1);	// still

			// changed the key... this one won't be cached
			provider.DecryptKey(Bytes(2,3,4)).Should().Equal(Bytes(4,6,8));
			decryptions.Should().Be(2);

			// cache is now full
			provider.DecryptKey(Bytes(3,4,5)).Should().Equal(Bytes(6,8,10));
			decryptions.Should().Be(3);
			provider.DecryptKey(Bytes(2,3,4)).Should().Equal(Bytes(4,6,8));
			decryptions.Should().Be(3); // still

			// first one fell out of the cache, so it will cause another decrypt
			provider.DecryptKey(Bytes(1,2,3)).Should().Equal(Bytes(2,4,6));
			decryptions.Should().Be(4);
		}
		public void DecryptKey_Context()
		{
			var mock = new Mock<IDataKeyProvider>();

			var context = new Dictionary<string, string>();
			context["multiplier"] = "3";

			int decryptions = 0;
			mock.Setup(x => x.DecryptKey(It.IsAny<byte[]>()))
				.Returns((byte[] input) => input.Select(x => (byte)(x * 2)).ToArray())
				.Callback(() => decryptions++);

			mock.Setup(x => x.DecryptKey(It.IsAny<byte[]>(), It.IsAny<IDictionary<string,string>>()))
				.Returns((byte[] input, IDictionary<string, string> ctx) =>
				{
					var multiplier = int.Parse(context["multiplier"]);
					return input.Select(x => (byte) (x * multiplier)).ToArray();
				})
				.Callback(() => decryptions++);

			var provider = new CachingDataKeyProvider(mock.Object, 2); 

			provider.DecryptKey(Bytes(1,2,3)).Should().Equal(Bytes(2,4,6));
			decryptions.Should().Be(1);

			context["multiplier"] = "3";
			provider.DecryptKey(Bytes(1,2,3), context).Should().Equal(Bytes(3,6,9));
			decryptions.Should().Be(2);

			provider.DecryptKey(Bytes(1,2,3)).Should().Equal(Bytes(2,4,6));
			decryptions.Should().Be(2); // still

			context["multiplier"] = "3";
			provider.DecryptKey(Bytes(1,2,3), context).Should().Equal(Bytes(3,6,9));
			decryptions.Should().Be(2); // still

			context["multiplier"] = "3";
			provider.DecryptKey(Bytes(1,2,3), context).Should().Equal(Bytes(3,6,9));
			decryptions.Should().Be(2); // still

			provider.DecryptKey(Bytes(1,2,3)).Should().Equal(Bytes(2,4,6));
			decryptions.Should().Be(2); // still

			context["multiplier"] = "0";
			provider.DecryptKey(Bytes(1,2,3), context).Should().Equal(Bytes(0,0,0));
			decryptions.Should().Be(3);

			provider.DecryptKey(Bytes(1,2,3)).Should().Equal(Bytes(2,4,6));
			decryptions.Should().Be(3); // still

			context["multiplier"] = "3";
			provider.DecryptKey(Bytes(1,2,3), context).Should().Equal(Bytes(3,6,9));
			decryptions.Should().Be(4);

			context["multiplier"] = "4";
			provider.DecryptKey(Bytes(1,2,3), context).Should().Equal(Bytes(4,8,12));
			decryptions.Should().Be(5);
		}