Subject: Ben Harris: 3des-ctr & blowfish-ctr

From: der Mouse <[email-masked]>
Date: Wed, 27 Apr 2005 02:45:15 -0400 (EDT)

I tried to send mail off-list to Ben Harris, but it timed out in the
queue - perhaps they don't like me:

>    ----- Transcript of session follows -----
> Ben Harris <[email-masked]>... Deferred: Connection timed out with mx-relay.chiark.greenend.org.uk.
> Message could not be delivered for 5 days
> Message will be deleted from queue

Perhaps it's just as well, because a response to me likely wouldn't
have gotten through - most of Ben's list posts come from .org.uk, which
would be blocked, even though the one I replied to came from .ac.uk,
which wouldn't.

Anyway, others may be interested too. :-)

What I wanted to say was....

> I've implemented 3des-ctr and blowfish-ctr in PuTTY, but I've had to
> leave them disabled because I haven't found another implementation to
> test against.  Does anyone in the WG know of one?

I just added them to mine - it proved to be even easier than I had
expected, a matter of five or ten minutes at most.

Care to do some testing?  I've got a server running on
truly-delicious.rodents.montreal.qc.ca port 22222 that you're welcome
to test against.  It's running with -neverauth, so you won't be able to
authenticate there even if you had a copy of my private key, but that's
not necessary for crypto interop tests.  (It is set to offer only
3des-ctr and blowfish-ctr for encryption, with all other encryption
algorithms disabled.)

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---

From: Ben Harris <[email-masked]>
Date: Wed, 27 Apr 2005 13:38:56 +0100

>queue - perhaps they don't like me:

SAUCE on chiark.greenend.org.uk tries to check your MAIL FROM address, gets
a 550 on connecting to your mail server and for some reason only returns
this to you as a temporary failure.  I'll ask my sysadmin why this doesn't
qualify as a permanent failure, but unless you're willing to accept mail
from chiark we're stuck communicating through the list.

>to test against.

Ooh, crunchy...

Well, I've discovered a mutual bug before even getting to NEWKEYS: both
PuTTY and Moussh were waiting for the other end to send a KEXINIT before
they'd send their own, which led to stalemate.  I've fixed this in PuTTY and
you should probably do the same for Moussh.

Having fixed that, I get your server closing the TCP connection on me after
I send the first encrypted packet, which suggests that we're disagreeing on
how the encryption should work.  I've fixed an obvious bug in our 3des-ctr
support (using the keys in the wrong order), bit that didn't help. I've put
copies of the packet logs at
<http://bjh21.me.uk/junk/putty.log.moussh.3des-ctr> and
<http://bjh21.me.uk/junk/putty.log.moussh.blowfish-ctr>.  Times there are
UTC+1; the connections were from 2002:5212:2743:1:2a0:40ff:fe2a:cb4c.

-- 
Ben Harris

---

From: der Mouse <[email-masked]>
Date: Wed, 27 Apr 2005 18:22:37 -0400 (EDT)

>> I tried to send mail off-list to Ben Harris, 
> [...]

Ben, I've tried to send you mail through another channel (mouse to
bjh21 on mail.netbsd.org).  This list message is just to give you a
heads-up in case it didn't work.

For everyone else - sorry for the chatter, and if everything works as
well as I hope this will be the last time Ben and I will have to use
the list for what really should be off-list mail.

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