SshData.cs:

- Remove ZeroReaderIndex from SshData; offset should instead be specified when instance is created/loaded.
- LoadBytes is now private, and is always invoked when a message is loaded.
- Eliminate ResetReader().
SshDataStream.cs:
- Added overload taking buffer, offset and count.
KeyExchange*Message.cs:
- Remove ResetReader() calls.
Message.cs:
- Remove ZeroReaderIndex override.
SftpMessage.cs:
- Pass offset and count to Load overload to allow skipping byte representing the message type.
- Remove ZeroReaderIndex override.
SftpSession.cs:
- Avoid buffering when packet contains full SFTP response message.
Session.cs:
- Pass offset and count to Load overload to allow skipping offset bytes.
General:
- Temporarily add (too) verbose tracing.

Author: drieseng

src/Renci.SshNet/BaseClient.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Net.Sockets;
 using System.Threading;
+using Renci.SshNet.Abstractions;
 using Renci.SshNet.Common;
 using Renci.SshNet.Messages.Transport;
 
@@ -221,6 +222,8 @@ public void Connect()
         /// <exception cref="ObjectDisposedException">The method was called after the client was disposed.</exception>
         public void Disconnect()
         {
+            DiagnosticAbstraction.Log(string.Format("{0} Disconnecting client", DateTime.Now.Ticks));
+
             CheckDisposed();
 
             OnDisconnecting();
@@ -317,6 +320,8 @@ private void Session_HostKeyReceived(object sender, HostKeyEventArgs e)
         /// </summary>
         public void Dispose()
         {
+            DiagnosticAbstraction.Log(string.Format("{0} Disposing client", DateTime.Now.Ticks));
+
             Dispose(true);
             GC.SuppressFinalize(this);
         }

src/Renci.SshNet/Common/SshData.cs

@@ -47,20 +47,7 @@ protected bool IsEndOfData
 
         private byte[] _loadedData;
         private int _offset;
-
-        /// <summary>
-        /// Gets the index that represents zero in current data type.
-        /// </summary>
-        /// <value>
-        /// The index of the zero reader.
-        /// </value>
-        protected virtual int ZeroReaderIndex
-        {
-            get
-            {
-                return 0;
-            }
-        }
+        private int _count;
 
         /// <summary>
         /// Gets the size of the message in bytes.
@@ -99,30 +86,41 @@ protected virtual void WriteBytes(SshDataStream stream)
         internal T OfType<T>() where T : SshData, new()
         {
             var result = new T();
-            result.LoadBytes(_loadedData, _offset);
-            result.LoadData();
+            result.Load(_loadedData, _offset, _count);
             return result;
         }
 
         /// <summary>
         /// Loads data from specified bytes.
         /// </summary>
-        /// <param name="value">Bytes array.</param>
-        /// <exception cref="ArgumentNullException"><paramref name="value"/> is <c>null</c>.</exception>
-        public void Load(byte[] value)
+        /// <param name="data">Bytes array.</param>
+        /// <exception cref="ArgumentNullException"><paramref name="data"/> is <c>null</c>.</exception>
+        public void Load(byte[] data)
         {
-            Load(value, 0);
+            if (data == null)
+                throw new ArgumentNullException("data");
+
+            LoadInternal(data, 0, data.Length);
         }
 
         /// <summary>
         /// Loads data from the specified buffer.
         /// </summary>
-        /// <param name="value">Bytes array.</param>
-        /// <param name="offset">The zero-based offset in <paramref name="value"/> at which to begin reading SSH data.</param>
-        /// <exception cref="ArgumentNullException"><paramref name="value"/> is <c>null</c>.</exception>
-        public void Load(byte[] value, int offset)
+        /// <param name="data">Bytes array.</param>
+        /// <param name="offset">The zero-based offset in <paramref name="data"/> at which to begin reading SSH data.</param>
+        /// <param name="count">The number of bytes to load.</param>
+        /// <exception cref="ArgumentNullException"><paramref name="data"/> is <c>null</c>.</exception>
+        public void Load(byte[] data, int offset, int count)
+        {
+            if (data == null)
+                throw new ArgumentNullException("data");
+
+            LoadInternal(data, offset, count);
+        }
+
+        private void LoadInternal(byte[] value, int offset, int count)
         {
-            LoadBytes(value, offset);
+            LoadBytes(value, offset, count);
             LoadData();
         }
 
@@ -136,40 +134,19 @@ public void Load(byte[] value, int offset)
         /// </summary>
         protected abstract void SaveData();
 
-        /// <summary>
-        /// Loads data bytes into internal buffer.
-        /// </summary>
-        /// <param name="bytes">The bytes.</param>
-        /// <exception cref="ArgumentNullException"><paramref name="bytes"/> is <c>null</c>.</exception>
-        protected void LoadBytes(byte[] bytes)
-        {
-            LoadBytes(bytes, 0);
-        }
-
         /// <summary>
         /// Loads data bytes into internal buffer.
         /// </summary>
         /// <param name="bytes">The bytes.</param>
         /// <param name="offset">The zero-based offset in <paramref name="bytes"/> at which to begin reading SSH data.</param>
-        /// <exception cref="ArgumentNullException"><paramref name="bytes"/> is <c>null</c>.</exception>
-        protected void LoadBytes(byte[] bytes, int offset)
+        /// <param name="count">The number of bytes to load.</param>
+        private void LoadBytes(byte[] bytes, int offset, int count)
         {
-            if (bytes == null)
-                throw new ArgumentNullException("bytes");
-
             _loadedData = bytes;
             _offset = offset;
+            _count = count;
 
-            _stream = new SshDataStream(bytes);
-            ResetReader();
-        }
-
-        /// <summary>
-        /// Resets internal data reader index.
-        /// </summary>
-        protected void ResetReader()
-        {
-            _stream.Position = ZeroReaderIndex + _offset;
+            _stream = new SshDataStream(bytes, _offset, count);
         }
 
         /// <summary>

src/Renci.SshNet/Common/SshDataStream.cs

@@ -30,6 +30,18 @@ public SshDataStream(byte[] buffer)
         {
         }
 
+        /// <summary>
+        /// Initializes a new non-resizable instance of the <see cref="SshDataStream"/> class based on the specified byte array.
+        /// </summary>
+        /// <param name="buffer">The array of unsigned bytes from which to create the current stream.</param>
+        /// <param name="offset">The zero-based offset in <paramref name="buffer"/> at which to begin reading SSH data.</param>
+        /// <param name="count">The number of bytes to load.</param>
+        /// <exception cref="ArgumentNullException"><paramref name="buffer"/> is <c>null</c>.</exception>
+        public SshDataStream(byte[] buffer, int offset, int count)
+            : base(buffer, offset, count)
+        {
+        }
+
         /// <summary>
         /// Gets a value indicating whether all data from the SSH data stream has been read.
         /// </summary>

src/Renci.SshNet/Messages/Message.cs

@@ -12,20 +12,6 @@ namespace Renci.SshNet.Messages
     /// </summary>
     public abstract class Message : SshData
     {
-        /// <summary>
-        /// Gets the index that represents zero in current data type.
-        /// </summary>
-        /// <value>
-        /// The index of the zero reader.
-        /// </value>
-        protected override int ZeroReaderIndex
-        {
-            get
-            {
-                return 1;
-            }
-        }
-
         /// <summary>
         /// Gets the size of the message in bytes.
         /// </summary>

src/Renci.SshNet/Messages/Transport/KeyExchangeDhInitMessage.cs

@@ -49,7 +49,6 @@ public KeyExchangeDhInitMessage(BigInteger clientExchangeValue)
         /// </summary>
         protected override void LoadData()
         {
-            ResetReader();
             _eBytes = ReadBinary();
         }
 

src/Renci.SshNet/Messages/Transport/KeyExchangeDhReplyMessage.cs

@@ -56,7 +56,6 @@ protected override int BufferCapacity
         /// </summary>
         protected override void LoadData()
         {
-            ResetReader();
             HostKey = ReadBinary();
             _fBytes = ReadBinary();
             Signature = ReadBinary();

src/Renci.SshNet/Messages/Transport/KeyExchangeEcdhInitMessage.cs

@@ -51,7 +51,6 @@ public KeyExchangeEcdhInitMessage(BigInteger d, BigInteger q)
         /// </summary>
         protected override void LoadData()
         {
-            ResetReader();
             QC = ReadBinary();
         }
 

src/Renci.SshNet/Messages/Transport/KeyExchangeEcdhReplyMessage.cs

@@ -49,7 +49,6 @@ protected override int BufferCapacity
         /// </summary>
         protected override void LoadData()
         {
-            ResetReader();
             KS = ReadBinary();
             QS = ReadBinary();
             Signature = ReadBinary();

src/Renci.SshNet/Messages/Transport/KeyExchangeInitMessage.cs

@@ -140,8 +140,6 @@ protected override int BufferCapacity
         /// </summary>
         protected override void LoadData()
         {
-            ResetReader();
-
             Cookie = ReadBytes(16);
             KeyExchangeAlgorithms = ReadNamesList();
             ServerHostKeyAlgorithms = ReadNamesList();

src/Renci.SshNet/PrivateKeyFile.cs

@@ -391,7 +391,7 @@ private class SshDataReader : SshData
         {
             public SshDataReader(byte[] data)
             {
-                LoadBytes(data);
+                Load(data);
             }
 
             public new uint ReadUInt32()