[BusyBox] can't add root user: passwd: unknown uid 0

[Rob Landley]

On Friday 29 July 2005 00:18, michael at michaelshiloh.com wrote:
> (Repost. I asked this question yesterday and have had no replies.
> If I have broken some rule please let me know how so that I can
> mend my ways.)
>
> Hi.
>
> I have busybox version 1.0. Shell seems OK and all the stuff I've played
> with seems to work, except for the users and groups:
>
> #   rm /etc/passwd /etc/shadow /etc/group
> #   rmdir /root
> #   touch /etc/passwd /etc/shadow /etc/group
> #   adduser -h /root root
> passwd: unknown uid 0
>
> Any tips?

Hmmm...  Apparently it's calling passwd before adding the user to the list, 
and passwd is (rightly) complaining that the current user isn't 
in /etc/passwd.

The code snippet that's barfing is this, from loginutils/passwd.c:

   pw = getpwnam(name);
    if (!pw) {
        bb_error_msg_and_die("Unknown user %s\n", name);
    }
    if (!amroot && pw->pw_uid != getuid()) {
        syslog(LOG_WARNING, "can't change pwd for `%s'", name);
        bb_error_msg_and_die("Permission denied.\n");
    }

The question is, how is adduser.c shelling out to passwd except at the _end_ 
of execution?  (Is it actually adding the user to the list, and just failing 
to set the password?  Does addpass -D make a difference?  Can you confirm 
that you're using the busybox version of addpass and not some other version 
calling busybox's passwd?)

Rob

P.S.  Why is if_i_am_not_root() _not_ just an #*%&#* inline test?  It's an if 
statement and an error message used from exactly one place, this does not 
deserve a function...