remove readonly of AuthenticationConnection in Session

[wizicer]

remove readonly of AuthenticationConnection in Session to support customize parallel connecting number.

Related Issues:
#215
#264
#409
#840

[wizicer]

            SetSshNetConcurrency(100);

        public static void SetSshNetConcurrency(int concurrency)
        {
            var field = typeof(Renci.SshNet.Session).GetField("AuthenticationConnection",
                         BindingFlags.Static |
                         BindingFlags.NonPublic);
            if (field != null)
            {
                field.SetValue(null, new SemaphoreLight(concurrency));
            }
        }

Utilize this to change it at startup. It works for me flawlessly.

[xantari]

Why are this and other PR's not being checked in. Is the project dead?

[drieseng]

@xantari because I don't have time and because this is clearly a hack. I'm open to alternate proposals but can't promise that I'll immediately find time to discuss them.

[ascott18]

Unfortunately the workaround above does not work on .NET Core 3+ due to dotnet/runtime#11571.

Instead, you can do this

var sessionSemaphoreField = typeof(Renci.SshNet.Session)
   .GetField("AuthenticationConnection", BindingFlags.Static | BindingFlags.NonPublic);

var semaphoreCountField = typeof(Renci.SshNet.Common.SemaphoreLight)
   .GetField("_currentCount", BindingFlags.Instance | BindingFlags.NonPublic);

object semaphore = sessionSemaphoreField.GetValue(null);

semaphoreCountField.SetValue(semaphore, concurrency);

or this, since SemaphoreLight does not validate against its provided initialCount:

var sessionSemaphoreField = typeof(Renci.SshNet.Session)
    .GetField("AuthenticationConnection", BindingFlags.Static | BindingFlags.NonPublic);

var semaphore = (Renci.SshNet.Common.SemaphoreLight)sessionSemaphoreField.GetValue(null);

// Add a much higher count to the semaphore to prevent pointless blocking of connection attempts.
semaphore.Release(100);

[ascott18]

@drieseng I would suggest that the proposal in this comment is the best solution - to remove this semaphore outright and leave throttling as a concern of the calling application.

[Rob-Hague]

The AuthenticationConnection semaphore has been removed in #1304

[WojciechNagorski]

This issue has been fixed in the 2024.0.0 version.