Re: [gdm-list] adding a command to externaly fill the username field

[Bob Doolittle <Robert Doolittle Sun COM>]

This is really easy to do in a PAM module.
Solaris does this for Sun Ray thin clients
via a module called sunray_get_user.so.
Just do what you have to, and provide a
pam_sm_authenticate handler that simply
calls pam_set_item for PAM_USER and returns
PAM_IGNORE so it doesn't actually contribute
to the authentication status.  Put your module
on top of gdm's PAM stack and voila!

This is a nice modular approach that doesn't
involve mucking with GDM internals, plus it's
easy for anyone to pick up your PAM module
and run it with out-of-the-box with gdm in
any Linux distro.

-Bob

syrius ml no-log org wrote:

> Hi,
>
> I'd like to be able to fill the username field externaly.
> I've tried to add a new fifo command to do that without success.
> I've added a GDM_SOP_DOLOGIN that takes the slave pid and the login
> name as arguments. 
> Looking at how GDM_SOP_COMMANDS are handled in
> gdm.c:gdm_handle_message I've duplicated the GDM_SOP_LOGIN test and
> tried to use 
> d->login=g_strdup (p);
> send_slave_command (d, GDM_NOTIFY_DOLOGIN);
>
> The slave is able to receive the message, but doesn't get the login.
> Anyway, it's seems that's not the good place to interact with
> pam_authenticate.
>
> At the moment, rather than doing that, i'm considering adding some
> stuff in the greeter so that it tells gdm to log with a given
> username. But i'm not sure this is the best way.
>
> Before I continue to I prefer to ask here, if there could be a
> better/simpler way to do that.
>
> Any advice ?
>
> Would it be better to write a pam library to do that ?
>
>