cvs commit: src/lib/libpam/modules/pam_unix pam_unix.8 pam_unix.c

[Yar Tikhiy]

On Mon, Apr 30, 2007 at 02:15:04PM +0100, Ceri Davies wrote:
> On Fri, Apr 27, 2007 at 08:07:40PM +0400, Yar Tikhiy wrote:
> > On Thu, Apr 26, 2007 at 12:46:38PM +0100, Ceri Davies wrote:
> > > On Thu, Apr 26, 2007 at 01:54:59PM +0300, Alexandr Kovalenko wrote:
> > > > Hello, Yar Tikhiy!
> > > > 
> > > > On Thu, Apr 26, 2007 at 06:39:01AM +0000, you wrote:
> > > > 
> > > > > yar         2007-04-26 06:39:01 UTC
> > > > > 
> > > > >   FreeBSD src repository
> > > > > 
> > > > >   Modified files:        (Branch: RELENG_6)
> > > > >     lib/libpam/modules/pam_unix pam_unix.8 pam_unix.c 
> > > > >   Log:
> > > > >   MFC:
> > > > >           pam_unix.c      1.52
> > > > >           pam_unix.8      1.13
> > > > >   
> > > > >     In account management, verify whether the account has been locked
> > > > >     with `pw lock', so that it's impossible to log into a locked account
> > > > >     using an alternative authentication mechanism, such as an ssh key.
> > > > >     This change affects only accounts locked with pw(8), i.e., having a
> > > > >     `*LOCKED*' prefix in their password hash field, so people still can
> > > > >     use a different pattern to disable password authentication only.
> > > > 
> > > > Using the very same logic you should also add checking for '*', and for
> > > > any other string, which cannot be in password hash of different
> > > > algorithms. By the way, what if some crypto algorithm, which will be
> > > > used for password hashing can produce hash, which contains substring
> > > > '*LOCKED*' ?
> > > 
> > > We really need to grow the same mechanism for this as Solaris has.
> > > The way that this works is:
> > > 
> > >   o If the password hash begins *NP* then the user has no password
> > >      and password authentication will always fail.
> > > 
> > >   o If the password hash begins *LK* then the account is considered
> > >      locked and all authentication fails.  Also, cron and at will
> > >      not run jobs for that user.
> > > 
> > >   o Anything else, the account is considered enabled (although of
> > >      course, password checking can still fail if the hash is not
> > >      valid).
> > > 
> > > I couldn't care less what the strings actually are, but we should
> > > probably use *LOCKED* for the locked case, although I can see that we
> > > may wish to use something else to provide a somewhat backward compatible
> > > route - those who have been using the string *LOCKED* as stated in the
> > > pw manual would get the same behaviour that they do now.
> > > 
> > > I am willing to work on this, but not without general agreement on the
> > > above.
> > 
> > I believe that general consensus in PR bin/71147 was that in FreeBSD
> > a *LOCKED* prefix means the account is totally locked out while a
> > single asterisk in the password field means password authentication
> > is disabled.  And, it isn't unfounded.  That practice has already
> > been supported by adduser(8) for quite a while.  Now OpenSSH, too,
> > looks for *LOCKED* as the FreeBSD-specific indication of an account
> > being locked out if PAM isn't used.  So I see my change to pam_unix(8)
> > just as a step in the direction we've already been moving in.  To
> > match Solaris, we just need to document our practice well.
> 
> Well, we currently have an *NP* case as per above, but not a *LK* case,
> so I disagree somewhat.

Why?  Now *LOCKED* in FreeBSD is nearly the same as *LK* in Solaris
with the only difference being that cron or at doesn't seem to care
about it.  And a single asterisk works for us as *NP* does in
Solaris, although it isn't a prefix, it occupies the whole password
field.  Did I miss anything?

-- 
Yar