ASN.1 refactoring

9 files changed, 123 insertions, 130 deletions

diff --git a/crypto/src/asn1/Asn1ObjectDescriptor.cs b/crypto/src/asn1/Asn1ObjectDescriptor.cs
index 20158af8e..e5cc42450 100644
--- a/crypto/src/asn1/Asn1ObjectDescriptor.cs
+++ b/crypto/src/asn1/Asn1ObjectDescriptor.cs
@@ -1,4 +1,5 @@
 using System;
+using System.IO;
 
 using Org.BouncyCastle.Utilities;
 
@@ -20,21 +21,21 @@ namespace Org.BouncyCastle.Asn1
             {
                 return (Asn1ObjectDescriptor)obj;
             }
-            else if (obj is Asn1Encodable)
+            else if (obj is IAsn1Convertible)
             {
-                Asn1Object asn1 = ((Asn1Encodable)obj).ToAsn1Object();
-                if (asn1 is Asn1ObjectDescriptor)
-                    return (Asn1ObjectDescriptor)asn1;
+                Asn1Object asn1Object = ((IAsn1Convertible)obj).ToAsn1Object();
+                if (asn1Object is Asn1ObjectDescriptor)
+                    return (Asn1ObjectDescriptor)asn1Object;
             }
-            if (obj is byte[])
+            else if (obj is byte[])
             {
                 try
                 {
                     return GetInstance(FromByteArray((byte[])obj));
                 }
-                catch (Exception e)
+                catch (IOException e)
                 {
-                    throw new ArgumentException("encoding error in GetInstance: " + e.ToString(), "obj");
+                    throw new ArgumentException("failed to construct object descriptor from byte[]: " + e.Message);
                 }
             }
 
diff --git a/crypto/src/asn1/Asn1OctetString.cs b/crypto/src/asn1/Asn1OctetString.cs
index 83156e091..d5766e299 100644
--- a/crypto/src/asn1/Asn1OctetString.cs
+++ b/crypto/src/asn1/Asn1OctetString.cs
@@ -1,5 +1,4 @@
 using System;
-using System.Collections;
 using System.IO;
 
 using Org.BouncyCastle.Utilities;
@@ -12,31 +11,6 @@ namespace Org.BouncyCastle.Asn1
     {
         internal static readonly byte[] EmptyOctets = new byte[0];
 
-        internal byte[] str;
-
-		/**
-         * return an Octet string from a tagged object.
-         *
-         * @param obj the tagged object holding the object we want.
-         * @param explicitly true if the object is meant to be explicitly
-         *              tagged false otherwise.
-         * @exception ArgumentException if the tagged object cannot
-         *              be converted.
-         */
-		public static Asn1OctetString GetInstance(
-			Asn1TaggedObject	obj,
-			bool				isExplicit)
-		{
-			Asn1Object o = obj.GetObject();
-
-			if (isExplicit || o is Asn1OctetString)
-			{
-				return GetInstance(o);
-			}
-
-			return BerOctetString.FromSequence(Asn1Sequence.GetInstance(o));
-		}
-
         /**
          * return an Octet string from the given object.
          *
@@ -49,6 +23,15 @@ namespace Org.BouncyCastle.Asn1
             {
                 return (Asn1OctetString)obj;
             }
+            //else if (obj is Asn1OctetStringParser)
+            else if (obj is IAsn1Convertible)
+            {
+                Asn1Object asn1Object = ((IAsn1Convertible)obj).ToAsn1Object();
+                if (asn1Object is Asn1OctetString)
+                {
+                    return (Asn1OctetString)asn1Object;
+                }
+            }
             else if (obj is byte[])
             {
                 try
@@ -60,39 +43,47 @@ namespace Org.BouncyCastle.Asn1
                     throw new ArgumentException("failed to construct OCTET STRING from byte[]: " + e.Message);
                 }
             }
-            // TODO: this needs to be deleted in V2
-            else if (obj is Asn1TaggedObject)
-            {
-                return GetInstance(((Asn1TaggedObject)obj).GetObject());
-            }
-            else if (obj is Asn1Encodable)
-            {
-                Asn1Object primitive = ((Asn1Encodable)obj).ToAsn1Object();
 
-                if (primitive is Asn1OctetString)
-                {
-                    return (Asn1OctetString)primitive;
-                }
+            throw new ArgumentException("illegal object in GetInstance: " + Platform.GetTypeName(obj), "obj");
+        }
+
+        /**
+         * return an Octet string from a tagged object.
+         *
+         * @param obj the tagged object holding the object we want.
+         * @param explicitly true if the object is meant to be explicitly
+         *              tagged false otherwise.
+         * @exception ArgumentException if the tagged object cannot
+         *              be converted.
+         */
+        public static Asn1OctetString GetInstance(Asn1TaggedObject taggedObject, bool declaredExplicit)
+        {
+            Asn1Object baseObject = taggedObject.GetObject();
+
+            if (declaredExplicit || baseObject is Asn1OctetString)
+            {
+                return GetInstance(baseObject);
             }
 
-            throw new ArgumentException("illegal object in GetInstance: " + Platform.GetTypeName(obj));
+            return BerOctetString.FromSequence(Asn1Sequence.GetInstance(baseObject));
         }
 
+        internal readonly byte[] contents;
+
         /**
          * @param string the octets making up the octet string.
          */
-        internal Asn1OctetString(
-            byte[] str)
+        internal Asn1OctetString(byte[] contents)
         {
-			if (str == null)
-				throw new ArgumentNullException("str");
+			if (null == contents)
+				throw new ArgumentNullException("contents");
 
-			this.str = str;
+			this.contents = contents;
         }
 
         public Stream GetOctetStream()
 		{
-			return new MemoryStream(str, false);
+			return new MemoryStream(contents, false);
 		}
 
 		public Asn1OctetStringParser Parser
@@ -102,7 +93,7 @@ namespace Org.BouncyCastle.Asn1
 
 		public virtual byte[] GetOctets()
         {
-            return str;
+            return contents;
         }
 
 		protected override int Asn1GetHashCode()
@@ -123,7 +114,7 @@ namespace Org.BouncyCastle.Asn1
 
 		public override string ToString()
 		{
-			return "#" + Hex.ToHexString(str);
+			return "#" + Hex.ToHexString(contents);
 		}
 	}
 }
diff --git a/crypto/src/asn1/Asn1Sequence.cs b/crypto/src/asn1/Asn1Sequence.cs
index a8f2af48a..e1d0fa675 100644
--- a/crypto/src/asn1/Asn1Sequence.cs
+++ b/crypto/src/asn1/Asn1Sequence.cs
@@ -19,16 +19,18 @@ namespace Org.BouncyCastle.Asn1
          * @param obj the object we want converted.
          * @exception ArgumentException if the object cannot be converted.
          */
-        public static Asn1Sequence GetInstance(
-            object obj)
+        public static Asn1Sequence GetInstance(object obj)
         {
             if (obj == null || obj is Asn1Sequence)
             {
                 return (Asn1Sequence)obj;
             }
-            else if (obj is Asn1SequenceParser)
+            //else if (obj is Asn1SequenceParser)
+            else if (obj is IAsn1Convertible)
             {
-                return GetInstance(((Asn1SequenceParser)obj).ToAsn1Object());
+                Asn1Object asn1Object = ((IAsn1Convertible)obj).ToAsn1Object();
+                if (asn1Object is Asn1Sequence)
+                    return (Asn1Sequence)asn1Object;
             }
             else if (obj is byte[])
             {
@@ -41,17 +43,8 @@ namespace Org.BouncyCastle.Asn1
                     throw new ArgumentException("failed to construct sequence from byte[]: " + e.Message);
                 }
             }
-            else if (obj is Asn1Encodable)
-            {
-                Asn1Object primitive = ((Asn1Encodable)obj).ToAsn1Object();
-                
-                if (primitive is Asn1Sequence)
-                {
-                    return (Asn1Sequence)primitive;
-                }
-            }
 
-            throw new ArgumentException("Unknown object in GetInstance: " + Platform.GetTypeName(obj), "obj");
+            throw new ArgumentException("illegal object in GetInstance: " + Platform.GetTypeName(obj), "obj");
         }
 
         /**
@@ -104,7 +97,7 @@ namespace Org.BouncyCastle.Asn1
                 return (Asn1Sequence) inner;
             }
 
-            throw new ArgumentException("Unknown object in GetInstance: " + Platform.GetTypeName(obj), "obj");
+            throw new ArgumentException("illegal object in GetInstance: " + Platform.GetTypeName(obj), "obj");
         }
 
         protected internal Asn1Sequence()
diff --git a/crypto/src/asn1/Asn1Set.cs b/crypto/src/asn1/Asn1Set.cs
index bf0567926..453627b7c 100644
--- a/crypto/src/asn1/Asn1Set.cs
+++ b/crypto/src/asn1/Asn1Set.cs
@@ -25,16 +25,18 @@ namespace Org.BouncyCastle.Asn1
          * @param obj the object we want converted.
          * @exception ArgumentException if the object cannot be converted.
          */
-        public static Asn1Set GetInstance(
-            object obj)
+        public static Asn1Set GetInstance(object obj)
         {
             if (obj == null || obj is Asn1Set)
             {
                 return (Asn1Set)obj;
             }
-            else if (obj is Asn1SetParser)
+            //else if (obj is Asn1SetParser)
+            else if (obj is IAsn1Convertible)
             {
-                return GetInstance(((Asn1SetParser)obj).ToAsn1Object());
+                Asn1Object asn1Object = ((IAsn1Convertible)obj).ToAsn1Object();
+                if (asn1Object is Asn1Set)
+                    return (Asn1Set)asn1Object;
             }
             else if (obj is byte[])
             {
@@ -47,17 +49,8 @@ namespace Org.BouncyCastle.Asn1
                     throw new ArgumentException("failed to construct set from byte[]: " + e.Message);
                 }
             }
-            else if (obj is Asn1Encodable)
-            {
-                Asn1Object primitive = ((Asn1Encodable)obj).ToAsn1Object();
-
-                if (primitive is Asn1Set)
-                {
-                    return (Asn1Set)primitive;
-                }
-            }
 
-            throw new ArgumentException("Unknown object in GetInstance: " + Platform.GetTypeName(obj), "obj");
+            throw new ArgumentException("illegal object in GetInstance: " + Platform.GetTypeName(obj), "obj");
         }
 
         /**
@@ -123,7 +116,7 @@ namespace Org.BouncyCastle.Asn1
                 return new DerSet(v, false);
             }
 
-            throw new ArgumentException("Unknown object in GetInstance: " + Platform.GetTypeName(obj), "obj");
+            throw new ArgumentException("illegal object in GetInstance: " + Platform.GetTypeName(obj), "obj");
         }
 
         protected internal Asn1Set()
diff --git a/crypto/src/asn1/BerOctetString.cs b/crypto/src/asn1/BerOctetString.cs
index c1e03106f..0dab617b9 100644
--- a/crypto/src/asn1/BerOctetString.cs
+++ b/crypto/src/asn1/BerOctetString.cs
@@ -30,20 +30,20 @@ namespace Org.BouncyCastle.Asn1
             case 0:
                 return EmptyOctets;
             case 1:
-                return octetStrings[0].str;
+                return octetStrings[0].contents;
             default:
             {
                 int totalOctets = 0;
                 for (int i = 0; i < count; ++i)
                 {
-                    totalOctets += octetStrings[i].str.Length;
+                    totalOctets += octetStrings[i].contents.Length;
                 }
 
                 byte[] str = new byte[totalOctets];
                 int pos = 0;
                 for (int i = 0; i < count; ++i)
                 {
-                    byte[] octets = octetStrings[i].str;
+                    byte[] octets = octetStrings[i].contents;
                     Array.Copy(octets, 0, str, pos, octets.Length);
                     pos += octets.Length;
                 }
@@ -76,8 +76,8 @@ namespace Org.BouncyCastle.Asn1
         {
         }
 
-        public BerOctetString(byte[] str)
-			: this(str, DefaultSegmentLimit)
+        public BerOctetString(byte[] contents)
+			: this(contents, DefaultSegmentLimit)
 		{
 		}
 
@@ -86,8 +86,8 @@ namespace Org.BouncyCastle.Asn1
         {
         }
 
-        public BerOctetString(byte[] str, int segmentLimit)
-            : this(str, null, segmentLimit)
+        public BerOctetString(byte[] contents, int segmentLimit)
+            : this(contents, null, segmentLimit)
         {
         }
 
@@ -96,8 +96,8 @@ namespace Org.BouncyCastle.Asn1
         {
         }
 
-        private BerOctetString(byte[] octets, Asn1OctetString[] elements, int segmentLimit)
-            : base(octets)
+        private BerOctetString(byte[] contents, Asn1OctetString[] elements, int segmentLimit)
+            : base(contents)
         {
             this.elements = elements;
             this.segmentLimit = segmentLimit;
@@ -109,7 +109,7 @@ namespace Org.BouncyCastle.Asn1
 		public IEnumerator GetEnumerator()
 		{
 			if (elements == null)
-                return new ChunkEnumerator(str, segmentLimit);
+                return new ChunkEnumerator(contents, segmentLimit);
 
 			return elements.GetEnumerator();
 		}
@@ -123,7 +123,7 @@ namespace Org.BouncyCastle.Asn1
         internal override bool EncodeConstructed()
         {
             // NOTE: Assumes BER encoding
-            return null != elements || str.Length > segmentLimit;
+            return null != elements || contents.Length > segmentLimit;
         }
 
         internal override int EncodedLength(bool withID)
@@ -132,7 +132,7 @@ namespace Org.BouncyCastle.Asn1
 
             // TODO This depends on knowing it's not DER
             //if (!EncodeConstructed())
-            //    return EncodedLength(withID, str.Length);
+            //    return EncodedLength(withID, contents.Length);
 
             //int totalLength = withID ? 4 : 3;
 
@@ -145,10 +145,10 @@ namespace Org.BouncyCastle.Asn1
             //}
             //else
             //{
-            //    int fullSegments = str.Length / segmentLimit;
+            //    int fullSegments = contents.Length / segmentLimit;
             //    totalLength += fullSegments * EncodedLength(true, segmentLimit);
 
-            //    int lastSegmentLength = str.Length - (fullSegments * segmentLimit);
+            //    int lastSegmentLength = contents.Length - (fullSegments * segmentLimit);
             //    if (lastSegmentLength > 0)
             //    {
             //        totalLength += EncodedLength(true, lastSegmentLength);
@@ -176,10 +176,10 @@ namespace Org.BouncyCastle.Asn1
             else
             {
                 int pos = 0;
-                while (pos < str.Length)
+                while (pos < contents.Length)
                 {
-                    int segmentLength = System.Math.Min(str.Length - pos, segmentLimit);
-                    Encode(asn1Out, true, str, pos, segmentLength);
+                    int segmentLength = System.Math.Min(contents.Length - pos, segmentLimit);
+                    Encode(asn1Out, true, contents, pos, segmentLength);
                     pos += segmentLength;
                 }
             }
diff --git a/crypto/src/asn1/DERExternal.cs b/crypto/src/asn1/DERExternal.cs
index d6255bb93..ae707a2f5 100644
--- a/crypto/src/asn1/DERExternal.cs
+++ b/crypto/src/asn1/DERExternal.cs
@@ -17,21 +17,21 @@ namespace Org.BouncyCastle.Asn1
             {
                 return (DerExternal)obj;
             }
-            if (obj is Asn1Encodable)
+            else if (obj is IAsn1Convertible)
             {
-                Asn1Object asn1 = ((Asn1Encodable)obj).ToAsn1Object();
-                if (asn1 is DerExternal)
-                    return (DerExternal)asn1;
+                Asn1Object asn1Object = ((IAsn1Convertible)obj).ToAsn1Object();
+                if (asn1Object is DerExternal)
+                    return (DerExternal)asn1Object;
             }
-            if (obj is byte[])
+            else if (obj is byte[])
             {
                 try
                 {
                     return GetInstance(FromByteArray((byte[])obj));
                 }
-                catch (Exception e)
+                catch (IOException e)
                 {
-                    throw new ArgumentException("encoding error in GetInstance: " + e.ToString(), "obj");
+                    throw new ArgumentException("failed to construct external from byte[]: " + e.Message);
                 }
             }
 
@@ -47,7 +47,7 @@ namespace Org.BouncyCastle.Asn1
                 return GetInstance(baseObject);
             }
 
-            return Asn1Sequence.GetInstance(taggedObject, false).ToAsn1External();
+            return Asn1Sequence.GetInstance(baseObject).ToAsn1External();
         }
 
 		private readonly DerObjectIdentifier directReference;
diff --git a/crypto/src/asn1/DerBitString.cs b/crypto/src/asn1/DerBitString.cs
index 3f3697d99..9cf84db1e 100644
--- a/crypto/src/asn1/DerBitString.cs
+++ b/crypto/src/asn1/DerBitString.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Diagnostics;
+using System.IO;
 using System.Text;
 
 using Org.BouncyCastle.Math;
@@ -22,17 +23,24 @@ namespace Org.BouncyCastle.Asn1
 		{
 			if (obj == null || obj is DerBitString)
 			{
-				return (DerBitString) obj;
+				return (DerBitString)obj;
 			}
-            if (obj is byte[])
+            //else if (obj is Asn1BitStringParser)
+            else if (obj is IAsn1Convertible)
+            {
+                Asn1Object asn1Object = ((IAsn1Convertible)obj).ToAsn1Object();
+                if (asn1Object is DerBitString)
+                    return (DerBitString)asn1Object;
+            }
+            else if (obj is byte[])
             {
                 try
                 {
-                    return (DerBitString)FromByteArray((byte[])obj);
+                    return GetInstance(FromByteArray((byte[])obj));
                 }
-                catch (Exception e)
+                catch (IOException e)
                 {
-                    throw new ArgumentException("encoding error in GetInstance: " + e.ToString());
+                    throw new ArgumentException("failed to construct BIT STRING from byte[]: " + e.Message);
                 }
             }
 
diff --git a/crypto/src/asn1/DerObjectIdentifier.cs b/crypto/src/asn1/DerObjectIdentifier.cs
index 3fd3d6401..4821d3b22 100644
--- a/crypto/src/asn1/DerObjectIdentifier.cs
+++ b/crypto/src/asn1/DerObjectIdentifier.cs
@@ -27,18 +27,26 @@ namespace Org.BouncyCastle.Asn1
         public static DerObjectIdentifier GetInstance(object obj)
         {
             if (obj == null || obj is DerObjectIdentifier)
-                return (DerObjectIdentifier) obj;
-
-            if (obj is Asn1Encodable)
             {
-                Asn1Object asn1Obj = ((Asn1Encodable)obj).ToAsn1Object();
-
-                if (asn1Obj is DerObjectIdentifier)
-                    return (DerObjectIdentifier)asn1Obj;
+                return (DerObjectIdentifier)obj;
+            }
+            else if (obj is IAsn1Convertible)
+            {
+                Asn1Object asn1Object = ((IAsn1Convertible)obj).ToAsn1Object();
+                if (asn1Object is DerObjectIdentifier)
+                    return (DerObjectIdentifier)asn1Object;
+            }
+            else if (obj is byte[])
+            {
+                try
+                {
+                    return GetInstance(FromByteArray((byte[])obj));
+                }
+                catch (IOException e)
+                {
+                    throw new ArgumentException("failed to construct object identifier from byte[]: " + e.Message);
+                }
             }
-
-            if (obj is byte[])
-                return (DerObjectIdentifier)FromByteArray((byte[])obj);
 
             throw new ArgumentException("illegal object in GetInstance: " + Platform.GetTypeName(obj), "obj");
         }
diff --git a/crypto/src/asn1/DerOctetString.cs b/crypto/src/asn1/DerOctetString.cs
index 7679d5eb1..55c099360 100644
--- a/crypto/src/asn1/DerOctetString.cs
+++ b/crypto/src/asn1/DerOctetString.cs
@@ -5,10 +5,9 @@ namespace Org.BouncyCastle.Asn1
     public class DerOctetString
         : Asn1OctetString
     {
-		/// <param name="str">The octets making up the octet string.</param>
-        public DerOctetString(
-			byte[] str)
-			: base(str)
+		/// <param name="contents">The octets making up the octet string.</param>
+        public DerOctetString(byte[] contents)
+			: base(contents)
         {
         }
 
@@ -29,12 +28,12 @@ namespace Org.BouncyCastle.Asn1
 
         internal override int EncodedLength(bool withID)
         {
-            return Asn1OutputStream.GetLengthOfEncodingDL(withID, str.Length);
+            return Asn1OutputStream.GetLengthOfEncodingDL(withID, contents.Length);
         }
 
         internal override void Encode(Asn1OutputStream asn1Out, bool withID)
         {
-            asn1Out.WriteEncodingDL(withID, Asn1Tags.OctetString, str);
+            asn1Out.WriteEncodingDL(withID, Asn1Tags.OctetString, contents);
         }
 
         internal static void Encode(Asn1OutputStream asn1Out, bool withID, byte[] buf, int off, int len)