init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Cms/KeyTransRecipientInformation.cs

@@ -0,0 +1,91 @@
+using System;
+using System.IO;
+using Org.BouncyCastle.Asn1;
+using Org.BouncyCastle.Asn1.Cms;
+using Org.BouncyCastle.Asn1.Pkcs;
+using Org.BouncyCastle.Asn1.X509;
+using Org.BouncyCastle.Crypto;
+using Org.BouncyCastle.Crypto.Parameters;
+using Org.BouncyCastle.Security;
+
+namespace Org.BouncyCastle.Cms;
+
+public class KeyTransRecipientInformation : RecipientInformation
+{
+	private KeyTransRecipientInfo info;
+
+	internal KeyTransRecipientInformation(KeyTransRecipientInfo info, CmsSecureReadable secureReadable)
+		: base(info.KeyEncryptionAlgorithm, secureReadable)
+	{
+		this.info = info;
+		rid = new RecipientID();
+		RecipientIdentifier recipientIdentifier = info.RecipientIdentifier;
+		try
+		{
+			if (recipientIdentifier.IsTagged)
+			{
+				Asn1OctetString instance = Asn1OctetString.GetInstance(recipientIdentifier.ID);
+				rid.SubjectKeyIdentifier = instance.GetOctets();
+			}
+			else
+			{
+				Org.BouncyCastle.Asn1.Cms.IssuerAndSerialNumber instance2 = Org.BouncyCastle.Asn1.Cms.IssuerAndSerialNumber.GetInstance(recipientIdentifier.ID);
+				rid.Issuer = instance2.Name;
+				rid.SerialNumber = instance2.SerialNumber.Value;
+			}
+		}
+		catch (IOException)
+		{
+			throw new ArgumentException("invalid rid in KeyTransRecipientInformation");
+		}
+	}
+
+	private string GetExchangeEncryptionAlgorithmName(AlgorithmIdentifier algo)
+	{
+		DerObjectIdentifier algorithm = algo.Algorithm;
+		if (PkcsObjectIdentifiers.RsaEncryption.Equals(algorithm))
+		{
+			return "RSA//PKCS1Padding";
+		}
+		if (PkcsObjectIdentifiers.IdRsaesOaep.Equals(algorithm))
+		{
+			RsaesOaepParameters instance = RsaesOaepParameters.GetInstance(algo.Parameters);
+			return "RSA//OAEPWITH" + DigestUtilities.GetAlgorithmName(instance.HashAlgorithm.Algorithm) + "ANDMGF1Padding";
+		}
+		return algorithm.Id;
+	}
+
+	internal KeyParameter UnwrapKey(ICipherParameters key)
+	{
+		byte[] octets = info.EncryptedKey.GetOctets();
+		string exchangeEncryptionAlgorithmName = GetExchangeEncryptionAlgorithmName(keyEncAlg);
+		try
+		{
+			IWrapper wrapper = WrapperUtilities.GetWrapper(exchangeEncryptionAlgorithmName);
+			wrapper.Init(forWrapping: false, key);
+			return ParameterUtilities.CreateKeyParameter(GetContentAlgorithmName(), wrapper.Unwrap(octets, 0, octets.Length));
+		}
+		catch (SecurityUtilityException e)
+		{
+			throw new CmsException("couldn't create cipher.", e);
+		}
+		catch (InvalidKeyException e2)
+		{
+			throw new CmsException("key invalid in message.", e2);
+		}
+		catch (DataLengthException e3)
+		{
+			throw new CmsException("illegal blocksize in message.", e3);
+		}
+		catch (InvalidCipherTextException e4)
+		{
+			throw new CmsException("bad padding in message.", e4);
+		}
+	}
+
+	public override CmsTypedStream GetContentStream(ICipherParameters key)
+	{
+		KeyParameter sKey = UnwrapKey(key);
+		return GetContentFromSessionKey(sKey);
+	}
+}