Initial Commit

iTechSharp/srcbc/asn1/cms/EnvelopedDataParser.cs

@@ -0,0 +1,106 @@
+using System;
+
+namespace Org.BouncyCastle.Asn1.Cms
+{
+	/**
+	* <pre>
+	* EnvelopedData ::= SEQUENCE {
+	*     version CMSVersion,
+	*     originatorInfo [0] IMPLICIT OriginatorInfo OPTIONAL,
+	*     recipientInfos RecipientInfos,
+	*     encryptedContentInfo EncryptedContentInfo,
+	*     unprotectedAttrs [1] IMPLICIT UnprotectedAttributes OPTIONAL
+	* }
+	* </pre>
+	*/
+	public class EnvelopedDataParser
+	{
+		private Asn1SequenceParser	_seq;
+		private DerInteger			_version;
+		private IAsn1Convertible	_nextObject;
+		private bool				_originatorInfoCalled;
+
+		public EnvelopedDataParser(
+			Asn1SequenceParser seq)
+		{
+			this._seq = seq;
+			this._version = (DerInteger)seq.ReadObject();
+		}
+
+		public DerInteger Version
+		{
+			get { return _version; }
+		}
+
+		public OriginatorInfo GetOriginatorInfo() 
+		{
+			_originatorInfoCalled = true; 
+
+			if (_nextObject == null)
+			{
+				_nextObject = _seq.ReadObject();
+			}
+
+			if (_nextObject is Asn1TaggedObjectParser && ((Asn1TaggedObjectParser)_nextObject).TagNo == 0)
+			{
+				Asn1SequenceParser originatorInfo = (Asn1SequenceParser)
+					((Asn1TaggedObjectParser)_nextObject).GetObjectParser(Asn1Tags.Sequence, false);
+				_nextObject = null;
+				return OriginatorInfo.GetInstance(originatorInfo.ToAsn1Object());
+			}
+
+			return null;
+		}
+
+		public Asn1SetParser GetRecipientInfos()
+		{
+			if (!_originatorInfoCalled)
+			{
+				GetOriginatorInfo();
+			}
+
+			if (_nextObject == null)
+			{
+				_nextObject = _seq.ReadObject();
+			}
+
+			Asn1SetParser recipientInfos = (Asn1SetParser)_nextObject;
+			_nextObject = null;
+			return recipientInfos;
+		}
+
+		public EncryptedContentInfoParser GetEncryptedContentInfo()
+		{
+			if (_nextObject == null)
+			{
+				_nextObject = _seq.ReadObject();
+			}
+
+			if (_nextObject != null)
+			{
+				Asn1SequenceParser o = (Asn1SequenceParser) _nextObject;
+				_nextObject = null;
+				return new EncryptedContentInfoParser(o);
+			}
+
+			return null;
+		}
+
+		public Asn1SetParser GetUnprotectedAttrs()
+		{
+			if (_nextObject == null)
+			{
+				_nextObject = _seq.ReadObject();
+			}
+
+			if (_nextObject != null)
+			{
+				IAsn1Convertible o = _nextObject;
+				_nextObject = null;
+				return (Asn1SetParser)((Asn1TaggedObjectParser)o).GetObjectParser(Asn1Tags.Set, false);
+			}
+        
+			return null;
+		}
+	}
+}