version：2.9.2

I configured my client to enable only arcfour256 algorithm, and then the server connecting to mina-sshd will encounter this exception, and the client connecting to a device supporting only arcfour256 algorithm through mina-sshd will also encounter this exception. But I’m fine with using the client connection directly

The following is the exception information：

Exception in thread "main" org.apache.sshd.common.SshException: [ssh-connection]: Failed (IllegalArgumentException) to execute: Bad arguments
at org.apache.sshd.common.future.AbstractSshFuture.lambda$verifyResult$2(AbstractSshFuture.java:146)
at org.apache.sshd.common.future.AbstractSshFuture.formatExceptionMessage(AbstractSshFuture.java:206)
at org.apache.sshd.common.future.AbstractSshFuture.verifyResult(AbstractSshFuture.java:145)
at org.apache.sshd.client.future.DefaultAuthFuture.verify(DefaultAuthFuture.java:56)
at org.apache.sshd.client.future.DefaultAuthFuture.verify(DefaultAuthFuture.java:35)
at org.apache.sshd.common.future.VerifiableFuture.verify(VerifiableFuture.java:121)
at sshTools.SshClientTool.createConnect(SshClientTool.java:213)
at sshTools.SshClientTool.main(SshClientTool.java:70)
Caused by: java.lang.IllegalArgumentException: Bad arguments
at javax.crypto.Cipher.update(Cipher.java:1941)
at org.apache.sshd.common.cipher.BaseCipher.update(BaseCipher.java:122)
at org.apache.sshd.common.session.helpers.AbstractSession.decode(AbstractSession.java:1644)
at org.apache.sshd.common.session.helpers.AbstractSession.messageReceived(AbstractSession.java:505)
at org.apache.sshd.common.session.helpers.AbstractSessionIoHandler.messageReceived(AbstractSessionIoHandler.java:64)
at org.apache.sshd.common.io.nio2.Nio2Session.handleReadCycleCompletion(Nio2Session.java:409)
at org.apache.sshd.common.io.nio2.Nio2Session$1.onCompleted(Nio2Session.java:382)
at org.apache.sshd.common.io.nio2.Nio2Session$1.onCompleted(Nio2Session.java:377)
at org.apache.sshd.common.io.nio2.Nio2CompletionHandler.lambda$completed$0(Nio2CompletionHandler.java:38)
at java.security.AccessController.doPrivileged(Native Method)
at org.apache.sshd.common.io.nio2.Nio2CompletionHandler.completed(Nio2CompletionHandler.java:37)
at sun.nio.ch.Invoker.invokeUnchecked(Invoker.java:126)
at sun.nio.ch.Invoker$2.run(Invoker.java:218)
at sun.nio.ch.AsynchronousChannelGroupImpl$1.run(AsynchronousChannelGroupImpl.java:112)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:750)

When I was debugging, I found that the parameter of the eighth packet was changed to -8, which led to subsequent exceptions.

Could it be that inCipherSize may not work for stream encryption algorithms? (such as arcfour256, also known as RC4), because stream encryption algorithms do not use the block concept.

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