2005-02-02 Sebastien Pouliot <sebastien@ximian.com>

	* SslClientStream.cs: Throw exception when we receive a null record.
	* RecordProtocol.cs: Added code to avoid blocking and endless loops
	if the data is incomplete or missing - even in the case the server
	side doesn't close the connection (see new cutcli tool).


svn path=/trunk/mcs/; revision=39997

3 files changed, 105 insertions, 26 deletions

diff --git a/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/ChangeLog b/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/ChangeLog
index bc8ffe4dbce..2a41f6d0937 100644
--- a/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/ChangeLog
+++ b/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/ChangeLog
@@ -1,3 +1,10 @@
+2005-02-02  Sebastien Pouliot  <sebastien@ximian.com>
+
+	* SslClientStream.cs: Throw exception when we receive a null record.
+	* RecordProtocol.cs: Added code to avoid blocking and endless loops
+	if the data is incomplete or missing - even in the case the server
+	side doesn't close the connection (see new cutcli tool).
+
 2004-12-15  Sebastien Pouliot  <sebastien@ximian.com>
 
 	* CipherSuite.cs: Removed unused MD5 and SHA1 instances created in 
diff --git a/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/RecordProtocol.cs b/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/RecordProtocol.cs
index 155e02be93f..412ca23a60e 100644
--- a/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/RecordProtocol.cs
+++ b/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/RecordProtocol.cs
@@ -24,9 +24,11 @@
 
 using System;
 using System.Collections;
-using System.IO;
+using System.IO;

+using System.Net.Sockets;
 using System.Security.Cryptography;
-using System.Security.Cryptography.X509Certificates;
+using System.Security.Cryptography.X509Certificates;

+using System.Threading;
 
 using Mono.Security.Protocol.Tls.Handshake;
 
@@ -70,7 +72,31 @@ namespace Mono.Security.Protocol.Tls
 				
 		#endregion
 
-		#region Reveive Record Methods
+		#region Reveive Record Methods

+

+		internal const int Timeout = 1000;

+

+		internal bool WaitForData ()

+		{

+			// problem: NetworkStream.ReadByte blocks until a byte is received

+			// and (maybe) no byte will ever be received

+			if (this.innerStream is NetworkStream)

+			{

+				NetworkStream ns = (this.innerStream as NetworkStream);

+				int delay = 10;

+				while (delay < Timeout)

+				{

+					if (ns.DataAvailable)

+						return true;

+					Thread.Sleep (delay);

+					delay *= 2;

+				}

+				// nothing to see, move along

+				return false;

+			}

+			// we assume other type of stream have their own timeout capabilities

+			return true;

+		}
 
 		public byte[] ReceiveRecord()
 		{
@@ -79,20 +105,25 @@ namespace Mono.Security.Protocol.Tls
 				throw new TlsException(
 					AlertDescription.InternalError,
 					"The session is finished and it's no longer valid.");
-			}
-	
-			// Try to read the Record Content Type
-			int type = this.innerStream.ReadByte();
+			}

+

+			if (!WaitForData ())

+			{

+				return null;

+			}

+

+			// Try to read the Record Content Type

+			int type = this.innerStream.ReadByte ();
 			if (type == -1)
-			{
+			{

 				return null;
-			}
+			}

 
 			// Set last handshake message received to None
 			this.context.LastHandshakeMsg = HandshakeType.ClientHello;
 
-			ContentType	contentType	= (ContentType)type;
-			byte[] buffer = this.ReadRecordBuffer(type);
+			ContentType	contentType	= (ContentType)type;

+			byte[] buffer = this.ReadRecordBuffer (type);
 
 			TlsStream message = new TlsStream(buffer);
 		
@@ -173,13 +204,19 @@ namespace Mono.Security.Protocol.Tls
 		}
 
 		private byte[] ReadClientHelloV2()
-		{
-			int msgLength			= this.innerStream.ReadByte();
-			byte[] message = new byte [msgLength];
-			this.innerStream.Read (message, 0, msgLength);
-
-			int msgType		= message [0];
-			if (msgType != 1)
+		{

+			int msgType = -1;

+			byte[] message = null;

+
+			int msgLength = this.innerStream.ReadByte();

+			if (msgLength > 0) 

+			{

+				message = new byte [msgLength];

+				if (this.innerStream.Read (message, 0, msgLength) == msgLength)

+					msgType = message [0];

+			}

+
+			if ((msgType != 1) || (message.Length < 9))
 			{
 				throw new TlsException(AlertDescription.DecodeError);
 			}
@@ -229,6 +266,19 @@ namespace Mono.Security.Protocol.Tls
 			this.context.ProtocolNegotiated = true;
 
 			return message;
+		}

+

+		private bool Wait (ref int delay)

+		{

+			if (delay < 10)

+				delay = 10;

+

+			if (delay >= Timeout)

+				return false;

+

+			Thread.Sleep (delay);

+			delay *= 2;

+			return true;

 		}
 
 		private byte[] ReadStandardRecordBuffer()
@@ -239,9 +289,21 @@ namespace Mono.Security.Protocol.Tls
 			// Read Record data
 			int		received	= 0;
 			byte[]	buffer		= new byte[length];
+			int n = 0;
 			while (received != length)
 			{
-				received += this.innerStream.Read(buffer, received, buffer.Length - received);
+				int incoming = this.innerStream.Read(buffer, received, buffer.Length - received);

+				// we risk an infinite loop is data isn't available

+				if (incoming == 0)

+				{

+					if (!Wait (ref n))

+						throw new TlsException (AlertLevel.Fatal, AlertDescription.CloseNotify);

+				}

+				else

+				{

+					n = 0; // reset

+				}

+				received += incoming;

 			}
 
 			// Check that the message has a valid protocol version
@@ -258,8 +320,11 @@ namespace Mono.Security.Protocol.Tls
 
 		private short ReadShort()
 		{
-			byte[] b = new byte[2];
-			this.innerStream.Read(b, 0, b.Length);
+			byte[] b = new byte[2];

+			if (this.innerStream.Read (b, 0, b.Length) != 2)

+			{

+				throw new TlsException (AlertLevel.Fatal, AlertDescription.DecodeError);

+			}
 
 			short val = BitConverter.ToInt16(b, 0);
 
diff --git a/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslClientStream.cs b/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslClientStream.cs
index ed99efe0257..926fb7af5b1 100644
--- a/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslClientStream.cs
+++ b/mcs/class/Mono.Security/Mono.Security.Protocol.Tls/SslClientStream.cs
@@ -688,7 +688,7 @@ namespace Mono.Security.Protocol.Tls
 		*/
 
 		internal void NegotiateHandshake()
-		{
+		{

 			lock (this)
 			{
 				try
@@ -707,8 +707,11 @@ namespace Mono.Security.Protocol.Tls
 					// Read server response
 					while (this.context.LastHandshakeMsg != HandshakeType.ServerHelloDone)
 					{
-						// Read next record
-						this.protocol.ReceiveRecord();
+						// Read next record

+						if (this.protocol.ReceiveRecord () == null)

+						{

+							throw new TlsException (AlertLevel.Fatal, AlertDescription.CloseNotify);

+						}
 					}
 
 					// Send client certificate if requested
@@ -737,8 +740,12 @@ namespace Mono.Security.Protocol.Tls
 					{
 						// If all goes well this will process messages:
 						// 		Change Cipher Spec
-						//		Server finished
-						this.protocol.ReceiveRecord();
+						//		Server finished

+						// Read next record

+						if (this.protocol.ReceiveRecord () == null)

+						{

+							throw new TlsException (AlertLevel.Fatal, AlertDescription.CloseNotify);

+						}

 					}
 
 					// Clear Key Info