ApacheMinaSSHD.NET

using ApacheMinaSSHD.NET.Wrapper;
using ApacheMinaSSHD.NET.Wrapper.Factories;

var server = AMNetSshServer.SetUpDefaultServer();
server.Host = "127.0.0.1";
server.Port = 2222;
server.Config.ApplyProductionDefaults();
server.Config.ApplyModernAlgorithmDefaults();

var hostKeys = new AMNetSimpleGeneratorHostKeyProvider("hostkey.ser");
hostKeys.setAlgorithm("RSA");
hostKeys.setKeySize(3072);
server.setKeyPairProvider(hostKeys);

server.SetFixedPasswordAuthenticator("admin", "changeme");
server.setFileSystemFactory(
    new AMNetVirtualFileSystemFactory(@"./sftp-root"));
server.setSubsystemFactories(
    new AMNetSftpSubsystemFactory());

server.Start();
Console.WriteLine("SFTP server running on port 2222");
Console.ReadLine();
server.Stop();

using ApacheMinaSSHD.NET.Wrapper;
using ApacheMinaSSHD.NET.Wrapper.Factories;
using ApacheMinaSSHD.NET.Wrapper.Abstractions;

var server = AMNetSshServer.SetUpDefaultServer();
server.Host = "127.0.0.1";
server.Port = 2222;
server.Config.ApplyProductionDefaults();
server.Config.ApplyModernAlgorithmDefaults();
server.setKeyPairProvider(
    new AMNetSimpleGeneratorHostKeyProvider("hostkey.ser"));

// Require both password AND keyboard-interactive
server.SetFixedPasswordAuthenticator("admin", "s3cret!");
server.SetFixedKeyboardInteractiveAuthenticator(
    "123456",
    prompt: "TOTP Code",
    instruction: "Enter your two-factor code.");

server.SetAuthenticationMethods(
    AMNetSshAuthenticationMethods.RequireAll(
        AMNetSshAuthenticationMethods.Password,
        AMNetSshAuthenticationMethods.KeyboardInteractive));

server.setFileSystemFactory(
    new AMNetVirtualFileSystemFactory(@"./sftp-root"));
server.setSubsystemFactories(
    new AMNetSftpSubsystemFactory());
server.Start();
Console.ReadLine();
server.Stop();

using ApacheMinaSSHD.NET.Wrapper;
using ApacheMinaSSHD.NET.Wrapper.Factories;
using ApacheMinaSSHD.NET.Wrapper.Abstractions;
using ApacheMinaSSHD.NET.Wrapper.Abstractions.Models;

var server = AMNetSshServer.SetUpDefaultServer();
server.Host = "127.0.0.1";
server.Port = 2222;
server.Config.ApplyProductionDefaults();
server.Config.ApplyModernAlgorithmDefaults();
server.SetFixedPasswordAuthenticator("admin", "changeme");
server.setKeyPairProvider(
    new AMNetSimpleGeneratorHostKeyProvider("hostkey.ser"));
server.setFileSystemFactory(
    new AMNetVirtualFileSystemFactory(@"./sftp-root"));

var sftp = new AMNetSftpSubsystemFactory();
sftp.addSftpEventListener(new MyEventListener());
sftp.setFileSystemAccessor(new MyFileAccessor());
server.setSubsystemFactories(sftp);
server.Start();
Console.ReadLine();
server.Stop();

class MyEventListener : AMNetSftpEventListener {
    public override void OnOpen(ISshEvent ctx)
        => Console.WriteLine($"Open: {ctx.SshHandle.PhysicalPath}");
    public override void OnWrite(ISshReadWrite ctx)
        => Console.WriteLine($"Write: {ctx.Length} bytes");
}

class MyFileAccessor : AMNetSftpFileSystemAccessor {
    public override bool ShouldIncludeDirectoryEntry(
        ISshFileSystemAccess context) {
        var name = Path.GetFileName(context.RemotePath);
        if (name?.StartsWith('.') == true) return false;
        return base.ShouldIncludeDirectoryEntry(context);
    }
}