Org.BouncyCastle.Cms.CmsEnvelopedDataStreamGenerator.Open C# (CSharp) Method

		private Stream Open(
			Stream				outStream,
			AlgorithmIdentifier	encAlgID,
			ICipherParameters	cipherParameters,
			Asn1EncodableVector	recipientInfos)
		{
			try
			{
				//
				// ContentInfo
				//
				BerSequenceGenerator cGen = new BerSequenceGenerator(outStream);

				cGen.AddObject(CmsObjectIdentifiers.EnvelopedData);

				//
				// Encrypted Data
				//
				BerSequenceGenerator envGen = new BerSequenceGenerator(
					cGen.GetRawOutputStream(), 0, true);

				envGen.AddObject(this.Version);

				Stream envRaw = envGen.GetRawOutputStream();
				Asn1Generator recipGen = _berEncodeRecipientSet
					?	(Asn1Generator) new BerSetGenerator(envRaw)
					:	new DerSetGenerator(envRaw);

				foreach (Asn1Encodable ae in recipientInfos)
				{
					recipGen.AddObject(ae);
				}

				recipGen.Close();

				BerSequenceGenerator eiGen = new BerSequenceGenerator(envRaw);
				eiGen.AddObject(CmsObjectIdentifiers.Data);
				eiGen.AddObject(encAlgID);

				Stream octetOutputStream = CmsUtilities.CreateBerOctetOutputStream(
					eiGen.GetRawOutputStream(), 0, false, _bufferSize);

				IBufferedCipher cipher = CipherUtilities.GetCipher(encAlgID.ObjectID);
				cipher.Init(true, new ParametersWithRandom(cipherParameters, rand));
				CipherStream cOut = new CipherStream(octetOutputStream, null, cipher);

				return new CmsEnvelopedDataOutputStream(this, cOut, cGen, envGen, eiGen);
			}
			catch (SecurityUtilityException e)
			{
				throw new CmsException("couldn't create cipher.", e);
			}
			catch (InvalidKeyException e)
			{
				throw new CmsException("key invalid in message.", e);
			}
			catch (IOException e)
			{
				throw new CmsException("exception decoding algorithm parameters.", e);
			}
		}

		public void TestTwoAesKek()
		{
			byte[] data = Encoding.Default.GetBytes("WallaWallaWashington");
			KeyParameter kek1 = CmsTestUtil.MakeAes192Key();
			KeyParameter kek2 = CmsTestUtil.MakeAes192Key();

			CmsEnvelopedDataStreamGenerator edGen = new CmsEnvelopedDataStreamGenerator();

			byte[]  kekId1 = new byte[] { 1, 2, 3, 4, 5 };
			byte[]  kekId2 = new byte[] { 5, 4, 3, 2, 1 };

			edGen.AddKekRecipient("AES192", kek1, kekId1);
			edGen.AddKekRecipient("AES192", kek2, kekId2);

			MemoryStream bOut = new MemoryStream();

			Stream outStream = edGen.Open(
				bOut,
				CmsEnvelopedDataGenerator.DesEde3Cbc);
			outStream.Write(data, 0, data.Length);

			outStream.Close();

			CmsEnvelopedDataParser ep = new CmsEnvelopedDataParser(bOut.ToArray());

			RecipientInformationStore recipients = ep.GetRecipientInfos();

			Assert.AreEqual(ep.EncryptionAlgOid, CmsEnvelopedDataGenerator.DesEde3Cbc);

			RecipientID recSel = new RecipientID();

			recSel.KeyIdentifier = kekId2;

			RecipientInformation recipient = recipients.GetFirstRecipient(recSel);

			Assert.AreEqual(recipient.KeyEncryptionAlgOid, "2.16.840.1.101.3.4.1.25");

			CmsTypedStream recData = recipient.GetContentStream(kek2);

			Assert.IsTrue(Arrays.AreEqual(data, CmsTestUtil.StreamToByteArray(recData.ContentStream)));

			ep.Close();
		}