SSH_PRIVSEP_USER configurable at runtime?

Corinna Vinschen vinschen at
Tue Apr 1 19:55:50 EST 2014

On Apr  1 14:46, Damien Miller wrote:
> On Mon, 31 Mar 2014, Corinna Vinschen wrote:
> > For instance, assuming you have a domain member machine MACH103, which
> > is member of the domain DOM1.  Assuming the machine as well as DOM1
> > and another dmain, DOM2, all have a user called "sshd", the automatically
> > generated Cygwin usernames will be
> > 
> >   MACH103+sshd     for the local account
> >   sshd             for the account in domain DOM1
> >   DOM2+sshd        for the account in domain DOM2.
> > 
> > Additionally, the admin can decide if the domain name gets prepended
> > every time, which results in "DOM1+sshd" as username in DOM1, and the
> > domain separator character can be chosen freely as well, for instance
> > a backslash (MACH103\sshd).
> > 
> > With domainnames being part of the username, this allows for so many
> > variations of the actual username, that a fixed name "sshd" or just
> > a compile time option will become a problem.
> > 
> > Any chance to get such a sshd_config option?
> I'm really loathe to add an option for this. Is there any way that
> sshd could figure out which account automatically? e.g. by having
> ssh-host-config ensure that ${machine}/sshd exists and is appropriately
> configured

I'm not sure I can follow.  Do you mean we should make sure that a
machine account sshd always exists and use that?

The problem is, sshd would still call getpwent("sshd").  This would work
for machine accounts on non-domain machines and for primary domain
accounts on domain member machines, but it would fail for a machine
account on a domain member machine when using the default account naming
rules.  And if the admin changed them to "always prepend domain name",
there would not be a "sshd" account at all.


Corinna Vinschen
Cygwin Maintainer
Red Hat
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: <>

More information about the openssh-unix-dev mailing list