Re: Feedback on draft-ssh-ext-info-00

denis bider <ietf-ssh3@denisbider.com> Sat, 05 December 2015 19:38 UTC

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Date: Thu, 03 Dec 2015 11:14:24 +0000
Subject: Re: Feedback on draft-ssh-ext-info-00
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From: denis bider <ietf-ssh3@denisbider.com>
To: Niels Möller <nisse@lysator.liu.se>
Cc: Damien Miller <djm@mindrot.org>, Markus Friedl <mfriedl@gmail.com>, ietf-ssh@netbsd.org
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Point taken. You are probably right.


Niels Möller <nisse@lysator.liu.se> , 12/3/2015 10:59 AM:
Regarding sending SERVICE_REQUEST and userauth messages back-to-back, 
 
denis bider <ietf-ssh3@denisbider.com> writes: 
 
> I'm not sure that we have a guarantee that the server must properly 
> handle this chaining. 
 
Have you seen any implementations broken is this way? 
 
I'd expect any reasonable server to process incoming messages properly, 
and in case it for some reason isn't ready to process the next logical 
message, simply delay reading and processing messages until it is ready. 
 
After all, the protocol is very intentionally designed to minimize the 
number of roundtrip delays. 
 
> One would imagine people would not do this, but I've dealt with an 
> implementation that discards KEXINIT if it's received in the same 
> network frame as the SSH version string. 
 
I think that's a different bug, and not very relevant. That's the point 
where you switch from new-line-delimited text data to the binary data, 
which needs some care to get right. 
 
Regards, 
/Niels 
 
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