java.lang.IllegalStateException: Authentication in progress!

[ext-marko-parikka]

We are running java application to move files from one place to another periodically by using Spring @scheduled annotation. In test environment, we are executing the process every minute. The process checks if there are files to be moved.

In this test case, there are no files at all to be moved. The sshclient is created like this:

SshClientBuilder.create()
          .addIdentities(sshKeyPair)
          .withHostname(host)
          .withPort(port)
          .withUsername(username)
          .build();

And sftp client like this: SftpClientBuilder.create().withClient(sshClient).build()

Once and a while this happens:
`29 May 2024 09:00:01,141 [ pool-746-thread-1] ERROR - Connection task failed with an error
java.lang.IllegalStateException: Authentication in progress!
at com.sshtools.client.AuthenticationProtocolClient.doNextAuthentication(AuthenticationProtocolClient.java:270)
at com.sshtools.client.AuthenticationProtocolClient.processMessage(AuthenticationProtocolClient.java:205)
at com.sshtools.synergy.ssh.TransportProtocol$5.doTask(TransportProtocol.java:2103)
at com.sshtools.common.ssh.ConnectionAwareTask.run(ConnectionAwareTask.java:49)
at com.sshtools.common.ssh.ExecutorOperationSupport$OperationTask.executeAllTasks(ExecutorOperationSupport.java:134)
at com.sshtools.common.ssh.ExecutorOperationSupport$OperationTask.run(ExecutorOperationSupport.java:89)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:829)

29 May 2024 09:13:01,114 [ pool-751-thread-1] ERROR - Connection task failed with an error
java.lang.IllegalStateException: Authentication in progress!
at com.sshtools.client.AuthenticationProtocolClient.doNextAuthentication(AuthenticationProtocolClient.java:270)
at com.sshtools.client.AuthenticationProtocolClient.processMessage(AuthenticationProtocolClient.java:205)
at com.sshtools.synergy.ssh.TransportProtocol$5.doTask(TransportProtocol.java:2103)
at com.sshtools.common.ssh.ConnectionAwareTask.run(ConnectionAwareTask.java:49)
at com.sshtools.common.ssh.ExecutorOperationSupport$OperationTask.executeAllTasks(ExecutorOperationSupport.java:134)
at com.sshtools.common.ssh.ExecutorOperationSupport$OperationTask.run(ExecutorOperationSupport.java:89)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:829)

29 May 2024 09:21:01,108 [ pool-755-thread-1] ERROR - Connection task failed with an error
java.lang.IllegalStateException: Authentication in progress!
at com.sshtools.client.AuthenticationProtocolClient.doNextAuthentication(AuthenticationProtocolClient.java:270)
at com.sshtools.client.AuthenticationProtocolClient.processMessage(AuthenticationProtocolClient.java:205)
at com.sshtools.synergy.ssh.TransportProtocol$5.doTask(TransportProtocol.java:2103)
at com.sshtools.common.ssh.ConnectionAwareTask.run(ConnectionAwareTask.java:49)
at com.sshtools.common.ssh.ExecutorOperationSupport$OperationTask.executeAllTasks(ExecutorOperationSupport.java:134)
at com.sshtools.common.ssh.ExecutorOperationSupport$OperationTask.run(ExecutorOperationSupport.java:89)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:829)`

And when I check the code, it should never happen:
if (currentAuthenticator != null) { // should never happen throw new IllegalStateException("Authentication in progress!"); }

[ext-marko-parikka]

These errors started to occur when we started to use version: 3.1.1. With 3.0.11 version, we did not face these kind of exceptions.

[mr-mister123]

Yes, it has to do with a fix i proposed for issue 82.

now the problem happens much less often (authentication failed) but when it happens, it will result in that exception, since there is still an race-condition anywhere. i will dig deeper into it in the next days.