Drop net6.0 target (#1580)

* Drop net6.0 target

* Update src/Renci.SshNet/Common/TaskToAsyncResult.cs

Co-authored-by: Rob Hague <rob.hague00@gmail.com>

* remove redundant #if

for some reason this made the compiler suddenly
realize that the plain text variables are unused.

* use TargetFrameworkIdentifier

this doesn't work in Directory.Build.props, moved it to Directory.Build.targets.

* fix null reference warnings in Benchmarks

seems like the warnings were (somehow) disabled here
before and were fixed by the previous TargetFrameworkIdentifier
change.

* fix unused plainTextOffset in AesGcmCipher.BclImpl

* CI retry

* more cosmetics

* more

* update README

* Revert "use TargetFrameworkIdentifier"

This reverts commit 076ede1.

---------

Co-authored-by: Rob Hague <rob.hague00@gmail.com>
Co-authored-by: Robert Hague <rh@johnstreetcapital.com>

Author: mus65

Directory.Build.props

@@ -31,7 +31,7 @@
   <!--
         Disable nullable warnings on old frameworks because of missing annotations.
   -->
-  <PropertyGroup Condition=" !$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net6.0')) ">
+  <PropertyGroup Condition=" !$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net8.0')) ">
     <NoWarn>$(NoWarn);CS8602;CS8604;CS8777</NoWarn>
   </PropertyGroup>
 

README.md

@@ -181,7 +181,7 @@ Private keys in PuTTY private key format can be encrypted using the following ci
 **SSH.NET** supports the following target frameworks:
 * .NETFramework 4.6.2 (and higher)
 * .NET Standard 2.0 and 2.1
-* .NET 6 (and higher)
+* .NET 8 (and higher)
 
 ## Building the library
 

src/Renci.SshNet/Abstractions/CancellationTokenSourceExtensions.cs

@@ -1,16 +1,16 @@
+#if !NET
 using System.Threading;
 using System.Threading.Tasks;
 
 namespace Renci.SshNet.Abstractions
 {
     internal static class CancellationTokenSourceExtensions
     {
-#if !NET8_OR_GREATER
         public static Task CancelAsync(this CancellationTokenSource cancellationTokenSource)
         {
             cancellationTokenSource.Cancel();
             return Task.CompletedTask;
         }
-#endif
     }
 }
+#endif

src/Renci.SshNet/Abstractions/SocketAbstraction.Async.cs

@@ -1,4 +1,4 @@
-#if NET6_0_OR_GREATER
+#if NET
 
 using System;
 using System.Diagnostics;
@@ -47,4 +47,4 @@ static async ValueTask SendAsyncCore(Socket socket, ReadOnlyMemory<byte> data, C
         }
     }
 }
-#endif // NET6_0_OR_GREATER
+#endif // NET

src/Renci.SshNet/Abstractions/SocketAbstraction.cs

@@ -311,7 +311,7 @@ public static int Read(Socket socket, byte[] buffer, int offset, int size, TimeS
             return totalBytesRead;
         }
 
-#if NET6_0_OR_GREATER == false
+#if !NET
         public static Task<int> ReadAsync(Socket socket, byte[] buffer, CancellationToken cancellationToken)
         {
             return socket.ReceiveAsync(buffer, 0, buffer.Length, cancellationToken);

src/Renci.SshNet/Abstractions/SocketExtensions.cs

@@ -1,4 +1,4 @@
-#if !NET6_0_OR_GREATER
+#if !NET
 using System;
 using System.Net;
 using System.Net.Sockets;
@@ -93,11 +93,11 @@ public static async Task ConnectAsync(this Socket socket, EndPoint remoteEndpoin
             {
                 args.RemoteEndPoint = remoteEndpoint;
 
-#if NET || NETSTANDARD2_1_OR_GREATER
+#if NETSTANDARD2_1
                 await using (cancellationToken.Register(o => ((AwaitableSocketAsyncEventArgs)o).SetCancelled(), args, useSynchronizationContext: false).ConfigureAwait(continueOnCapturedContext: false))
 #else
                 using (cancellationToken.Register(o => ((AwaitableSocketAsyncEventArgs)o).SetCancelled(), args, useSynchronizationContext: false))
-#endif // NET || NETSTANDARD2_1_OR_GREATER
+#endif
                 {
                     await args.ExecuteAsync(socket.ConnectAsync);
                 }
@@ -112,11 +112,11 @@ public static async Task<int> ReceiveAsync(this Socket socket, byte[] buffer, in
             {
                 args.SetBuffer(buffer, offset, length);
 
-#if NET || NETSTANDARD2_1_OR_GREATER
+#if NETSTANDARD2_1
                 await using (cancellationToken.Register(o => ((AwaitableSocketAsyncEventArgs)o).SetCancelled(), args, useSynchronizationContext: false).ConfigureAwait(continueOnCapturedContext: false))
 #else
                 using (cancellationToken.Register(o => ((AwaitableSocketAsyncEventArgs)o).SetCancelled(), args, useSynchronizationContext: false))
-#endif // NET || NETSTANDARD2_1_OR_GREATER
+#endif
                 {
                     await args.ExecuteAsync(socket.ReceiveAsync);
                 }

src/Renci.SshNet/Abstractions/StreamExtensions.cs

@@ -1,18 +1,16 @@
-#if !NET && !NETSTANDARD2_1_OR_GREATER
+#if NETFRAMEWORK || NETSTANDARD2_0
 using System.IO;
 using System.Threading.Tasks;
-#endif
 
 namespace Renci.SshNet.Abstractions
 {
     internal static class StreamExtensions
     {
-#if !NET && !NETSTANDARD2_1_OR_GREATER
         public static ValueTask DisposeAsync(this Stream stream)
         {
             stream.Dispose();
             return default;
         }
-#endif
     }
 }
+#endif

src/Renci.SshNet/ClientAuthentication.cs

@@ -105,11 +105,11 @@ private bool TryAuthenticate(ISession session,
             {
                 authenticationException = new SshAuthenticationException(string.Format(CultureInfo.InvariantCulture,
                                                                                        "No suitable authentication method found to complete authentication ({0}).",
-#if NET || NETSTANDARD2_1_OR_GREATER
+#if NET || NETSTANDARD2_1
                                                                                        string.Join(',', allowedAuthenticationMethods)))
 #else
                                                                                        string.Join(",", allowedAuthenticationMethods)))
-#endif // NET || NETSTANDARD2_1_OR_GREATER
+#endif
                 ;
                 return false;
             }

src/Renci.SshNet/Common/Extensions.cs

@@ -48,7 +48,7 @@ internal static ServiceName ToServiceName(this byte[] data)
 
         internal static BigInteger ToBigInteger(this byte[] data)
         {
-#if NETSTANDARD2_1_OR_GREATER || NET6_0_OR_GREATER
+#if NETSTANDARD2_1 || NET
             return new BigInteger(data, isBigEndian: true);
 #else
             var reversed = new byte[data.Length];
@@ -62,7 +62,7 @@ internal static BigInteger ToBigInteger(this byte[] data)
         /// </summary>
         public static BigInteger ToBigInteger2(this byte[] data)
         {
-#if NETSTANDARD2_1_OR_GREATER || NET6_0_OR_GREATER
+#if NETSTANDARD2_1 || NET
             return new BigInteger(data, isBigEndian: true, isUnsigned: true);
 #else
             if ((data[0] & (1 << 7)) != 0)
@@ -95,7 +95,7 @@ public static byte[] ToByteArray(this BigInteger bigInt, bool isUnsigned = false
         }
 #endif
 
-#if !NET6_0_OR_GREATER
+#if !NET
         public static long GetBitLength(this BigInteger bigint)
         {
             // Taken from https://github.com/dotnet/runtime/issues/31308

src/Renci.SshNet/Common/SshData.cs

@@ -372,11 +372,11 @@ protected void Write(BigInteger data)
         /// <param name="data">name-list data to write.</param>
         protected void Write(string[] data)
         {
-#if NET || NETSTANDARD2_1_OR_GREATER
+#if NET || NETSTANDARD2_1
             Write(string.Join(',', data), Ascii);
 #else
             Write(string.Join(",", data), Ascii);
-#endif // NET || NETSTANDARD2_1_OR_GREATER
+#endif
         }
 
         /// <summary>