ssh pubkey exchange failing at send_pubkey_test

[Hans-Georg Scherneck]

My cygwin runs on a Windows 7. My problem is similar to a previous one

  * /From/: Christophe Sauthier <christophe dot sauthier at gmail dot com>
  * /To/: Cygwin List <cygwin at cygwin dot com>
  * /Date/: Wed, 13 Apr 2005 10:39:14 +0200
  * /Subject/: Re: Strange behaviour of Openssh

however it's really different. My problem occurs earlier in the process.

I try to log in with ssh passwordless into a server that I've set up. 
sshd is running there. I can log in with password.
When I set up the crypto (ssh-keygen -t ecdsa) and install the pub key 
at the host, I can't login anymore, not by defaulting to password either.

What can cause communication to stop at this point:
     debug3: send_pubkey_test
     debug2: we sent a publickey packet, wait for reply
     Connection closed by 999.999.999.999
i.e. pubkey does not arrive at the client, abort.
You can see the whole monty at froste.oso.chalmers.se/hgs/cygwin
the ssh -vvv debug and the server's sshd_config  Tell me if you need to 
see more.
On two other pairs of machines, however, it's working according to the 
book. I cannot see the difference.

Causes I can exclude:
sshd_config requests Protocol 2

  * My key pairs are in /home/user/.ssh with the privileges set as needed.
  * The pub key has been cat >> server:/home/user/.ssh/authorized_keys,
    privil: -rw-r--r-
  * The log shows that id_ecdsa is detected and okayed.
  * I have renewed .ssh/knwon_hosts
  * My /var/empty is not writable except for root.

Does the pubkey sending go through a different port, not 22?
Is there a timeout ?

These are the catalogs involved that are reported in the debug log
On the host side:
ls -l .ssh/
total 29
drwx------+ 1 Hans Georg Scherneck Ingen    0 2012-01-20 12:05 .
drwx------+ 1 Hans Georg Scherneck Ingen    0 2012-01-20 12:00 ..
-rw-r--r--  1 Hans Georg Scherneck Ingen  175 2012-01-19 20:52 
authorized_keys
-rw-------  1 Hans Georg Scherneck Ingen  227 2012-01-20 12:00 id_ecdsa
-rw-r--r--  1 Hans Georg Scherneck Ingen  186 2012-01-20 12:00 id_ecdsa.pub
-rw-r--r--  1 Hans Georg Scherneck Ingen 1963 2012-01-20 12:04 known_hosts
(when this machine acts as a server, I can login with key exchange 
instead of password. Both machines' /etc/ssh_config are exactly equal 
and use default settings only)

On the server side:
ls -la .ssh
drwx------+ 1 HGS None    0 Jan 20 12:01 .
drwx------+ 1 HGS None    0 Jan 20 15:36 ..
-rw-r--r--  1 HGS None  361 Jan 20 12:02 authorized_keys
-rw-r--r--  1 HGS None 1009 Jan 20 15:37 known_hosts

-- 
Med vänliga hälsningar / With best regards yours             -----
Hans-Georg Scherneck                                       /   A   \
---------------------+----------------------------------- |   / \   |
. Telephone&  -fax   | Chalmers University of Technology   \       /
. +46 31 772 5556    | Earth and Space Sciences              -----
. +46 31 772 5590 fx |&  Onsala Space Observatory             | |
. E-Mail:            | SE-439 92  Onsala, Sweden             /   \
. hgs@chalmers.se    | http://www.chalmers.se/rss       ----------------
. Ocean Loading Serv.| froste.oso.chalmers.se/loading   /===\ ,===//===\
. Gravimeter         | froste.oso.chalmers.se/hgs/SCG  /    /`===,/    /
---------------------+---------------------------------\===//===' \===/


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple