SSH as discard server?

rapier rapier at
Sat Aug 7 01:47:53 AEST 2021

Understood. That's why I was looking at doing in cipher_crypt. All the 
other mechanism should JustWork(tm). Maybe.

That said, that's sort of what I do in the none cipher switch in hpnssh. 
Instead of running through a decrypt process it just does a memcpy from 
src to dst and returns.


On 8/6/21 11:27 AM, Brian Candler wrote:
> After authentication, the ssh client is almost certainly going to 
> request a channel.  If you don't acknowledge that, it will hang. It can 
> then request further channels at any point during the connection.  
> Handling this requires decrypting the traffic.  Any "sink" server that 
> doesn't bother to decrypt packets will need to be written in a way which 
> is very specific to the way the client uses SSH.
>  From the intro to rfc4254:
>     This document describes the SSH Connection Protocol.  It provides
>     interactive login sessions, remote execution of commands, forwarded
>     TCP/IP connections, and forwarded X11 connections.  **All of these channels are multiplexed into a single encrypted tunnel**.
> (my emphasis)

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