Add BitString parsers

1 files changed, 56 insertions, 0 deletions

diff --git a/crypto/src/asn1/BerBitStringParser.cs b/crypto/src/asn1/BerBitStringParser.cs
new file mode 100644
index 000000000..656538ba1
--- /dev/null
+++ b/crypto/src/asn1/BerBitStringParser.cs
@@ -0,0 +1,56 @@
+using System;
+using System.IO;
+
+using Org.BouncyCastle.Utilities.IO;
+
+namespace Org.BouncyCastle.Asn1
+{
+    /// <summary>A parser for indefinite-length BIT STRINGs.</summary>
+    internal class BerBitStringParser
+        : Asn1BitStringParser
+    {
+        private readonly Asn1StreamParser m_parser;
+
+        private ConstructedBitStream m_bitStream;
+
+        internal BerBitStringParser(Asn1StreamParser parser)
+        {
+            m_parser = parser;
+        }
+
+        public Stream GetOctetStream()
+        {
+            return m_bitStream = new ConstructedBitStream(m_parser, true);
+        }
+
+        public Stream GetBitStream()
+        {
+            return m_bitStream = new ConstructedBitStream(m_parser, false);
+        }
+
+        public int PadBits
+        {
+            get { return m_bitStream.PadBits; }
+        }
+
+        public Asn1Object ToAsn1Object()
+        {
+            try
+            {
+                return Parse(m_parser);
+            }
+            catch (IOException e)
+            {
+                throw new Asn1ParsingException("IOException converting stream to byte array: " + e.Message, e);
+            }
+        }
+
+        internal static BerBitString Parse(Asn1StreamParser sp)
+        {
+            ConstructedBitStream bitStream = new ConstructedBitStream(sp, false);
+            byte[] data = Streams.ReadAll(bitStream);
+            int padBits = bitStream.PadBits;
+            return new BerBitString(data, padBits);
+        }
+    }
+}