Re: [gdm-list] Re: gdm user and pass fields together

[Brian Cameron <Brian Cameron sun com>]

Michael:

> > > I'm a gnome user from Brazil, here in my company we're migrating to
> > > GNU/Linux desktop. We're using gnome e gdm.
> > > My boss wants that the login screen (GDM) shows up the user
> > > e password fields together, not username <enter> and password <enter>.
> > > Furthemore, he wants that gdm save and remember last username login,
> > > so the user only types the password and log in.
> > >
> > > Is this possible? 
> >
> > GDM does not currently allow this to be configured.  You would probably
> > need to rework the way GDM interacts with PAM to make this work.  Also,
> > putting both fields on the same screen doesn't save you any typing, it
> > would just mean you would have to hit <Tab> rather than <Enter>.
>
> actually marcos is requesting a feature i am also missing at gdm, and i
> think the ability to configure gdm for seperate user- and password-fields
> would be more convenient for users migrating from windows and macos. i don't
> exactly know how the windows-loginmanager works, but the one at macos x lets
> the USER decide, which key he wants to hit for switching from the user-field
> to the password-field. i.e.: if the cursor is in the user-field and the
> username is entered one can press EITHER <tab> OR <enter> to set the focus
> on the password-field. if the entered username has NO password and <enter>
> has been pressed, login occurs - otherwise the focus remains on the
> password-field until the password is confirmed with <enter>.

I'm no power Windows user, but when I've used the XP login screen, the
username and password fields are not displayed at the same time.  It seems
to work similar to how GDM works.  Though perhaps it can be configured
differently than how I've seen it work.

I do understand what Marcos is asking for and I agree that GDM would be
more usable if it displayed both username and password entries at the same
time.

However, keep in mind that GDM depends upon PAM for authentication.  The
idea behind PAM is that the PAM module determines how authentication
happens.  In theory, you should be able to write a PAM module that
authenticates the user via eye-scanner or gets the username from a
smartcard rather than making the user type it in.  It may be possible to
write a PAM module that prompts the username and password at the same time.
Assuming GDM properly implements the PAM interface, then GDM should
"just work" and let the PAM module drive the authentication process.  I'm
not sure many people have written custom PAM modules to be used with GDM,
so doing this properly might expose some problems in GDM that need fixing.

I would recommend that if people are interested in making GDM work this
way, that the first step would be to explore the topic on a PAM mailing
list and see how this could be done within the PAM framework.  Assuming
it is possible, writing up the PAM module and getting it to work with
GDM would be the next step.  I would be happy to help with the efforts,
but someone who really wants this feature should drive figuring out the
proper solution.  Personally I'd be more interested in helping by working
on the bugs that will cause GDM to not work well with custom PAM modules
than writing the PAM module part.  I'm pretty sure bugs are there.

> i think this strategy combines the two ways of entering username/password.
> brian, you are right that the <tab>-way does not save time, but it does not
> cost any either.

For what its worth, the current GDM program accepts both Tab and Enter to
take you to the next entry.  It just doesn't display them both at the same
time.  I'm just saying that this is a usability change, and doesn't affect
speed of getting through the login screen.  Except, perhaps, in those
situations where the user worries that they might have mistyped their
username and has to hit the "Cancel" button or possibly do a failed login
to find out.

> but i think the macosx-way of login would make gdm more
> flexible: the ones that like to stay at the traditional one-field gdm could
> p.ex. configure gdm to put the password-field on top of the user-field after
> the username has been entered. the ones who would prefer two fields, could
> place the password-field right below the username-field (or somewhere else
> with the graphical greeter).
>
> one further advantage that the two-field solution has over the one-fielded
> gdm: the user sees right away if he has a typo at the username-field. at the
> one-fielded gdm: *hmmm* wait ... did i type "michael" or "michal"? *hrmpf*
> (<enter> at the password-field ... waiting x seconds ... retry).

I do agree that displaying them both on the same screen would be more
usable.  The reason this hasn't been implemented even though many people
have asked for it is because it is harder to change than you might think
at first impression.  Most people seem to loose interest in helping
with this feature after finding out it isn't an easy change.

Brian