adduser/deluser on postinst

[Vincent Bernat <bernat@luffy.cx>]

Hi !

I need some  advice on bug #435671.  I agree with  the bug reporter that
the user  handling part of  xrdp should be  rewritten. I have  looked at
what is done  in other packages and  in most of them gentent  is used to
check the  user existence but  there is no  check that this is  really a
system user  (so the user can  be unrelated to the  package). Because of
this,  some  package (ntp)  just  skip the  test  and  use adduser  with
--quiet.

On  deletion, some package  do not  use --system  option of  deluser, so
delete a legit  non-system user without warning. On  my system, there is
gdm, openntpd, openssh and vde2.

In summary, I  think a package should just  use adduser --quiet --system
in postinst and  deluser --quiet --system on purge  without checking for
existence. It would be convenient for adduser --quiet --system to return
an error if the user exists  but is not a system user (actually, without
--quiet, it says the user exists and is a user system, I will report the
bug).

What do you think ?
-- 
BOFH excuse #45:
virus attack, luser responsible