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"Key Re-Exchange" Event

Posted: Thu 21 Oct 2021 10:39
by Nils
Is it possible to know in the TScSSHClient, when the SSH Server initiates a Key Re-Exchangehttps://datatracker.ietf.org/doc/html/rfc4253#section-9

Background to that question is the following. We have a connection to a SSH server which is kept active for 24 hours. every 20 to 30 seconds the client sends a command to the server via TScSSHShell with ExecuteCommand, to get some counters from the server. Sometimes this command seems to collide with the Key Re-Exchange.

This means the server sends the Key Re-Exchange request and waits for an according response. But the client tries to send the command with with the Shell. Which results in the following error message on the server:

Unexpected packet type 94, expected 21

Packet type 94 means SSH_MSG_CHANNEL_OPEN (94) and 21 is SSH_MSG_NEWKEYS (21).

I'm now looking for a way to get notified when the Key Re-Exchange happens so i can time the Shell accordingly.

Re: "Key Re-Exchange" Event

Posted: Wed 27 Oct 2021 11:16
by YanishevskiyVI
Hi Nils!

Thank you for contacting Devart and for the info provided!

Please be informed that the issue is already known and it will be fixed in the next releases!

Should you have any other questions, do not hesitate to ask!

Regards,
Vitaliy

Re: "Key Re-Exchange" Event

Posted: Thu 28 Oct 2021 07:52
by Nils
Thank you for the reply. Looking forward to the next release!