From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: [PATCH 2/3] gnu: pam_unix.so Add use_first_pass option.
Date: Thu, 27 Oct 2016 14:51:02 +0200
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To: John Darrington <john@darrington.wattle.id.au>
Cc: guix-devel@gnu.org, John Darrington <jmd@gnu.org>

John Darrington <john@darrington.wattle.id.au> skribis:

> On Sun, Oct 23, 2016 at 05:45:50PM -0400, Leo Famulari wrote:
>
>      > diff --git a/gnu/system/pam.scm b/gnu/system/pam.scm
>      > index 4546c1a..0278db6 100644
>      > --- a/gnu/system/pam.scm
>      > +++ b/gnu/system/pam.scm
>      > @@ -217,7 +217,7 @@ should be a file-like object used as the messa=
ge-of-the-day."
>      >                           (pam-entry
>      >                            (control "required")
>      >                            (module "pam_unix.so")
>      > -                          (arguments '("nullok")))
>      > +                          (arguments '("nullok" "use_first_pass")=
))
>=20=20=20=20=20=20
>      pam_unix(8) says:
>=20=20=20=20=20=20
>      use_first_pass
>          The argument use_first_pass forces the module to use a previous =
stacked modules
>          password and will never prompt the user - if no password is avai=
lable or the
>          password is not appropriate, the user will be denied access.
>=20=20=20=20=20=20
>      I don't understand exactly what this means for GuixSD. Can you expla=
in
>      it to us? :)
>
> On its own it does nothing.  It makes more sense in context with the othe=
r patch I sent.
> With this option in place, one can extend the unix-pam-service with anoth=
er pam service
> (such as krb5-pam), and if the krb5 authentication fails (for example bec=
ause I am not
> at work) then the password I gave will be presented to the regular pam_un=
ix login.=20
> I won't be prompted for it again.

In that case, instead of hardcoding =E2=80=9Cuse_first_pass=E2=80=9D here, =
would it be
possible for the pam-krb5 service to extend =E2=80=98pam-root-service-type=
=E2=80=99 with
a procedure that automatically adds =E2=80=9Cuse_first_pass=E2=80=9D where =
needed?

See elogind and =E2=80=98pam-extension-procedure=E2=80=99 in (gnu services =
desktop) for
an example of that.

Thanks,
Ludo=E2=80=99.