1 files changed, 103 insertions, 0 deletions
diff --git a/crypto/src/bcpg/PublicKeyEncSessionPacket.cs b/crypto/src/bcpg/PublicKeyEncSessionPacket.cs
new file mode 100644
index 000000000..d10605f1d
--- /dev/null
+++ b/crypto/src/bcpg/PublicKeyEncSessionPacket.cs
@@ -0,0 +1,103 @@
+using System;
+using System.IO;
+
+using Org.BouncyCastle.Math;
+
+namespace Org.BouncyCastle.Bcpg
+{
+	/// <remarks>Basic packet for a PGP public key.</remarks>
+	public class PublicKeyEncSessionPacket
+		: ContainedPacket //, PublicKeyAlgorithmTag
+	{
+		private int version;
+		private long keyId;
+		private PublicKeyAlgorithmTag algorithm;
+		private BigInteger[] data;
+
+		internal PublicKeyEncSessionPacket(
+			BcpgInputStream bcpgIn)
+		{
+			version = bcpgIn.ReadByte();
+
+			keyId |= (long)bcpgIn.ReadByte() << 56;
+			keyId |= (long)bcpgIn.ReadByte() << 48;
+			keyId |= (long)bcpgIn.ReadByte() << 40;
+			keyId |= (long)bcpgIn.ReadByte() << 32;
+			keyId |= (long)bcpgIn.ReadByte() << 24;
+			keyId |= (long)bcpgIn.ReadByte() << 16;
+			keyId |= (long)bcpgIn.ReadByte() << 8;
+			keyId |= (uint)bcpgIn.ReadByte();
+
+			algorithm = (PublicKeyAlgorithmTag) bcpgIn.ReadByte();
+
+			switch ((PublicKeyAlgorithmTag) algorithm)
+			{
+				case PublicKeyAlgorithmTag.RsaEncrypt:
+				case PublicKeyAlgorithmTag.RsaGeneral:
+					data = new BigInteger[]{ new MPInteger(bcpgIn).Value };
+					break;
+				case PublicKeyAlgorithmTag.ElGamalEncrypt:
+				case PublicKeyAlgorithmTag.ElGamalGeneral:
+					data = new BigInteger[]
+					{
+						new MPInteger(bcpgIn).Value,
+						new MPInteger(bcpgIn).Value
+					};
+					break;
+				default:
+					throw new IOException("unknown PGP public key algorithm encountered");
+			}
+		}
+
+		public PublicKeyEncSessionPacket(
+			long					keyId,
+			PublicKeyAlgorithmTag	algorithm,
+			BigInteger[]			data)
+		{
+			this.version = 3;
+			this.keyId = keyId;
+			this.algorithm = algorithm;
+			this.data = (BigInteger[]) data.Clone();
+		}
+
+		public int Version
+		{
+			get { return version; }
+		}
+
+		public long KeyId
+		{
+			get { return keyId; }
+		}
+
+		public PublicKeyAlgorithmTag Algorithm
+		{
+			get { return algorithm; }
+		}
+
+		public BigInteger[] GetEncSessionKey()
+		{
+			return (BigInteger[]) data.Clone();
+		}
+
+		public override void Encode(
+			BcpgOutputStream bcpgOut)
+		{
+			MemoryStream bOut = new MemoryStream();
+			BcpgOutputStream pOut = new BcpgOutputStream(bOut);
+
+			pOut.WriteByte((byte) version);
+
+			pOut.WriteLong(keyId);
+
+			pOut.WriteByte((byte)algorithm);
+
+			for (int i = 0; i != data.Length; i++)
+			{
+				MPInteger.Encode(pOut, data[i]);
+			}
+
+			bcpgOut.WritePacket(PacketTag.PublicKeyEncryptedSession , bOut.ToArray(), true);
+		}
+	}
+}