Send client connection attributes. Fixes #293

Author: bgrainger

src/MySqlConnector/MySqlConnector.csproj

@@ -20,15 +20,7 @@
     <RepositoryUrl>https://github.com/mysql-net/MySqlConnector.git</RepositoryUrl>
   </PropertyGroup>
 
-  <ItemGroup Condition=" '$(TargetFramework)' == 'net451' ">
-    <PackageReference Include="System.Buffers" Version="4.0.0" />
-    <PackageReference Include="System.Runtime.InteropServices.RuntimeInformation" Version="4.0.0" />
-    <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.0.0" />
-    <Reference Include="System.Data" />
-    <Reference Include="System.Transactions" />
-  </ItemGroup>
-
-  <ItemGroup Condition=" '$(TargetFramework)' == 'net46' ">
+  <ItemGroup Condition=" '$(TargetFramework)' == 'net451' OR '$(TargetFramework)' == 'net46' ">
     <PackageReference Include="System.Buffers" Version="4.0.0" />
     <PackageReference Include="System.Runtime.InteropServices.RuntimeInformation" Version="4.0.0" />
     <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.0.0" />
@@ -39,6 +31,7 @@
   <ItemGroup Condition=" '$(TargetFramework)' == 'netstandard1.3' ">
     <PackageReference Include="System.Buffers" Version="4.3.0" />
     <PackageReference Include="System.Data.Common" Version="4.3.0" />
+    <PackageReference Include="System.Diagnostics.Process" Version="4.3.0" />
     <PackageReference Include="System.Net.NameResolution" Version="4.3.0" />
     <PackageReference Include="System.Net.Security" Version="4.3.0" />
     <PackageReference Include="System.Security.Cryptography.Algorithms" Version="4.3.0" />

src/MySqlConnector/Serialization/ChangeUserPayload.cs

@@ -4,7 +4,7 @@ namespace MySql.Data.Serialization
 {
 	internal class ChangeUserPayload
 	{
-		public static PayloadData Create(string user, byte[] authResponse, string schemaName)
+		public static PayloadData Create(string user, byte[] authResponse, string schemaName, byte[] connectionAttributes)
 		{
 			var writer = new PayloadWriter();
 
@@ -16,6 +16,8 @@ public static PayloadData Create(string user, byte[] authResponse, string schema
 			writer.WriteByte((byte) CharacterSet.Utf8Mb4Binary);
 			writer.WriteByte(0);
 			writer.WriteNullTerminatedString("mysql_native_password");
+			if (connectionAttributes != null)
+				writer.Write(connectionAttributes);
 
 			return new PayloadData(new ArraySegment<byte>(writer.ToBytes()));
 		}

src/MySqlConnector/Serialization/HandshakeResponse41Packet.cs

@@ -19,6 +19,7 @@ private static PayloadWriter CreateCapabilitiesPayload(ProtocolCapabilities serv
 				(string.IsNullOrWhiteSpace(cs.Database) ? 0 : ProtocolCapabilities.ConnectWithDatabase) |
 				(cs.UseAffectedRows ? 0 : ProtocolCapabilities.FoundRows) |
 				(useCompression ? ProtocolCapabilities.Compress : ProtocolCapabilities.None) |
+				(serverCapabilities & ProtocolCapabilities.ConnectionAttributes) |
 				additionalCapabilities));
 			writer.WriteInt32(0x4000_0000);
 			writer.WriteByte((byte) CharacterSet.Utf8Mb4Binary);
@@ -32,10 +33,9 @@ public static byte[] InitSsl(ProtocolCapabilities serverCapabilities, Connection
 			return CreateCapabilitiesPayload(serverCapabilities, cs, useCompression, ProtocolCapabilities.Ssl).ToBytes();
 		}
 
-		public static byte[] Create(InitialHandshakePacket handshake, ConnectionSettings cs, bool useCompression)
+		public static byte[] Create(InitialHandshakePacket handshake, ConnectionSettings cs, bool useCompression, byte[] connectionAttributes)
 		{
 			// TODO: verify server capabilities
-
 			var writer = CreateCapabilitiesPayload(handshake.ProtocolCapabilities, cs, useCompression);
 			writer.WriteNullTerminatedString(cs.UserID);
 			var authenticationResponse = AuthenticationUtility.CreateAuthenticationResponse(handshake.AuthPluginData, 0, cs.Password);
@@ -48,6 +48,9 @@ public static byte[] Create(InitialHandshakePacket handshake, ConnectionSettings
 			if ((handshake.ProtocolCapabilities & ProtocolCapabilities.PluginAuth) != 0)
 				writer.WriteNullTerminatedString("mysql_native_password");
 
+			if (connectionAttributes != null)
+				writer.Write(connectionAttributes);
+
 			return writer.ToBytes();
 		}
 	}

src/MySqlConnector/Serialization/MySqlSession.cs

@@ -1,8 +1,12 @@
 using System;
+using System.Diagnostics;
+using System.Globalization;
 using System.IO;
 using System.Net;
 using System.Net.Security;
 using System.Net.Sockets;
+using System.Reflection;
+using System.Runtime.InteropServices;
 using System.Security.Authentication;
 using System.Security.Cryptography;
 using System.Security.Cryptography.X509Certificates;
@@ -233,7 +237,11 @@ public async Task ConnectAsync(ConnectionSettings cs, IOBehavior ioBehavior, Can
 				await InitSslAsync(initialHandshake.ProtocolCapabilities, cs, ioBehavior, cancellationToken).ConfigureAwait(false);
 			}
 
-			var response = HandshakeResponse41Packet.Create(initialHandshake, cs, m_useCompression);
+			m_supportsConnectionAttributes = (initialHandshake.ProtocolCapabilities & ProtocolCapabilities.ConnectionAttributes) != 0;
+			if (m_supportsConnectionAttributes && s_connectionAttributes == null)
+				s_connectionAttributes = CreateConnectionAttributes();
+
+			var response = HandshakeResponse41Packet.Create(initialHandshake, cs, m_useCompression, m_supportsConnectionAttributes ? s_connectionAttributes : null);
 			payload = new PayloadData(new ArraySegment<byte>(response));
 			await SendReplyAsync(payload, ioBehavior, cancellationToken).ConfigureAwait(false);
 			payload = await ReceiveReplyAsync(ioBehavior, cancellationToken).ConfigureAwait(false);
@@ -270,7 +278,7 @@ public async Task ResetConnectionAsync(ConnectionSettings cs, IOBehavior ioBehav
 			{
 				// optimistically hash the password with the challenge from the initial handshake (supported by MariaDB; doesn't appear to be supported by MySQL)
 				var hashedPassword = AuthenticationUtility.CreateAuthenticationResponse(AuthPluginData, 0, cs.Password);
-				var payload = ChangeUserPayload.Create(cs.UserID, hashedPassword, cs.Database);
+				var payload = ChangeUserPayload.Create(cs.UserID, hashedPassword, cs.Database, m_supportsConnectionAttributes ? s_connectionAttributes : null);
 				await SendAsync(payload, ioBehavior, cancellationToken).ConfigureAwait(false);
 				payload = await ReceiveReplyAsync(ioBehavior, cancellationToken).ConfigureAwait(false);
 				if (payload.HeaderByte == AuthenticationMethodSwitchRequestPayload.Signature)
@@ -768,6 +776,46 @@ private void VerifyState(State state1, State state2)
 				throw new InvalidOperationException("Expected state to be ({0}|{1}) but was {2}.".FormatInvariant(state1, state2, m_state));
 		}
 
+		private static byte[] CreateConnectionAttributes()
+		{
+			var attributesWriter = new PayloadWriter();
+			attributesWriter.WriteLengthEncodedString("_client_name");
+			attributesWriter.WriteLengthEncodedString("MySqlConnector");
+			attributesWriter.WriteLengthEncodedString("_client_version");
+			attributesWriter.WriteLengthEncodedString(typeof(MySqlSession).GetTypeInfo().Assembly.GetCustomAttribute<AssemblyInformationalVersionAttribute>().InformationalVersion);
+			try
+			{
+				var os = RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ? "Windows" :
+					RuntimeInformation.IsOSPlatform(OSPlatform.Linux) ? "Linux" :
+						RuntimeInformation.IsOSPlatform(OSPlatform.Linux) ? "macOS" : null;
+				var osDetails = RuntimeInformation.OSDescription;
+				var platform = RuntimeInformation.ProcessArchitecture.ToString();
+				if (os != null)
+				{
+					attributesWriter.WriteLengthEncodedString("_os");
+					attributesWriter.WriteLengthEncodedString(os);
+				}
+				attributesWriter.WriteLengthEncodedString("_os_details");
+				attributesWriter.WriteLengthEncodedString(osDetails);
+				attributesWriter.WriteLengthEncodedString("_platform");
+				attributesWriter.WriteLengthEncodedString(platform);
+			}
+			catch (PlatformNotSupportedException)
+			{
+			}
+			using (var process = Process.GetCurrentProcess())
+			{
+				attributesWriter.WriteLengthEncodedString("_pid");
+				attributesWriter.WriteLengthEncodedString(process.Id.ToString(CultureInfo.InvariantCulture));
+			}
+			var connectionAttributes = attributesWriter.ToBytes();
+
+			var writer = new PayloadWriter();
+			writer.WriteLengthEncodedInteger((ulong) connectionAttributes.Length);
+			writer.Write(connectionAttributes);
+			return writer.ToBytes();
+		}
+
 		private enum State
 		{
 			// The session has been created; no connection has been made.
@@ -798,6 +846,8 @@ private enum State
 			Failed,
 		}
 
+		static byte[] s_connectionAttributes;
+
 		readonly object m_lock;
 		readonly ArraySegmentHolder<byte> m_payloadCache;
 		State m_state;
@@ -814,5 +864,6 @@ private enum State
 		MySqlDataReader m_activeReader;
 		bool m_useCompression;
 		bool m_isSecureConnection;
+		bool m_supportsConnectionAttributes;
 	}
 }

src/MySqlConnector/Serialization/PayloadWriter.cs

@@ -43,6 +43,13 @@ public void WriteLengthEncodedInteger(ulong value)
 			}
 		}
 
+		public void WriteLengthEncodedString(string value)
+		{
+			var bytes = Encoding.UTF8.GetBytes(value);
+			WriteLengthEncodedInteger((ulong) bytes.Length);
+			m_writer.Write(bytes);
+		}
+
 		public void WriteNullTerminatedString(string value)
 		{
 			var bytes = Encoding.UTF8.GetBytes(value);

src/MySqlConnector/Serialization/ProtocolCapabilities.cs

@@ -105,7 +105,7 @@ internal enum ProtocolCapabilities
 		/// <summary>
 		/// Permits connection attributes in Protocol::HandshakeResponse41.
 		/// </summary>
-		ConnectAttributes = 0x10_0000,
+		ConnectionAttributes = 0x10_0000,
 
 		/// <summary>
 		/// Understands length-encoded integer for auth response data in Protocol::HandshakeResponse41.