Re: [HEADSUP] making /bin/sh the default shell for root

On 2021-09-22 12:26, Marek Zarychta wrote:
> W dniu 22.09.2021 o 19:46, Warner Losh pisze:
>> On Wed, Sep 22, 2021 at 9:35 AM John Baldwin <jhb@freebsd.org> wrote:
>> 
>>> On 9/22/21 1:36 AM, Baptiste Daroussin wrote:
>>>> Hello,
>>>> 
>>>> TL;DR: this is not a proposal to deorbit csh from base!!!
>>>> 
>>>> For years now, csh is the default root shell for FreeBSD, csh can be
>>> confusing
>>>> as a default shell for many as all other unix like settled on a bourne
>>> shell
>>>> compatible interactive shell: zsh, bash, or variant of ksh.
>>>> 
>>>> Recently our sh(1) has receive update to make it more user friendly in
>>>> interactive mode:
>>>> * command completion (thanks pstef@)
>>>> * improvement in the emacs mode, to make it behave by default like other
>>> shells
>>>> * improvement in the vi mode (in particular the vi edit to respect
>>> $EDITOR)
>>>> * support for history as described by POSIX.
>>>> 
>>>> This makes it a usable shell by default, which is why I would like to
>>> propose to
>>>> make it the default shell for root starting FreeBSD 14.0-RELEASE (not
>>> MFCed)
>>>> 
>>>> If no strong arguments has been raised until October 15th, I will make
>>> this
>>>> proposal happen.
>>>> 
>>>> Again just in case: THIS IS NOT A PROPOSAL TO REMOVE CSH FROM BASE!
>>> 
>>> I think this is fine.  I would also be fine with either removing 'toor'
>>> from the
>>> default password file or just leaving it as-is for POLA.  (I would 
>>> probably
>>> prefer removing it outright.)
>>> 
>> 
>> I think this is also fine. I also think we should remove toor from the
>> default
>> password file for one fewer attack surfaces. I strongly prefer this. Users
>> that want toor can add it to their system and/or provisioning scripts.
>> 
>> Warner
>> 
> 
> I am curious which attacks you are referring to since I have never heard
> of attacks on toor account. I have seen a lot of malware attacking root,
> admin, nobody, and other accounts, but never toor.
In the 30 some yrs I've been on UNIX and the likes. I've only ever known
~half a dozen administrators that ever choose toor. Those that want to
continue doing so, will not be prevented from continuing to do so.
> 
> TBH toor might be handy as a backdoor account if you are familiar with
> FreeBSD enough to take advantage of it. It can also act as an account of
> last resort when someone breaks into your system and changes root
> password, wipes ssh keys etc, so it cuts both ways, not even mentioning
>  POLA.
TBH this is a non-issue. toor is simply an alias to root.
Anyone that has a root hacked system need only spin up the FreeBSD mini
iso/img, mount their hacked system && hack back into shape. :-)

Props to all the work and proposed changes here. Thanks! :-)

--Chris

P.S. This is NOT a bike shed.
> 
> The transition from csh to sh as a default root's shell will probably
> save some CPU cycles for people using Chef, Ansible, etc thus pushing
> FreeBSD toward green computing. Sysadmins bound to csh will be fine
> until it remains in the base system and chsh works.
> 
> I shouldn't probably post here since I am only a voice from the userbase
> but can't help doing so.
> 
> Kind regards,