running bind as user other than root

[Ralf Hildebrandt]

On Mon, Feb 28, 2000 at 10:20:52AM -0600, Duane Cox wrote:
> 
> I'm interested in running bind as a user other than root.  Is this a good
> or bad idea?  Other than a root user, should the new user be in the root
> group?  Here is my situation.        

Running BIND as unprivileged user is definitively a good idea!
Create an unprivileged user bind, belonging to group bind:

/etc/passwd:
bind:*:12:26::/:                     

/etc/group:
bind:*:26:bind                     

> I want to run ns1 and ns2, and have ns1 update ns2 via rsync over ssh.
>(to avoid having to setup ns2 manually and to do the zone transfers)  This
>all works A OK right now using the user root, and logging into ns2 as root
>via ssh, but allowing someone to ssh into a machine with the user root
>scares me.  My other option was to run the daemon as another user, say
>"named" and set the file permissions to match that.  But my question is, is
>this open for more of a security problem, and if not, will I have to setup
>other files, ie. /var/log/messages so that this new user can write errors to
>it.         

RUNNING ANY DAEMON AS ROOT IS BAD. For obvious reasons:

* Let there be an error in the daemon which allows execution of arbitrary
  commands -> root compromise
* Let there be an error in the daemon which allows writing/access to
  arbitrary files -> root compromise

Tip: Let BIND run as unprivileged user in chroot-jail (
named -t /jail -u bind -g bind
) to add additional security (every little bit helps).

You might adjust this a little to be able to rsync/scp the zonefiles to the
jail.

--
Ralf Hildebrandt <R.Hildebrandt at tu-bs.de> www.stahl.bau.tu-bs.de/~hildeb
I work for an investment bank. I have dealt with code written by stock
exchanges. I have seen how the computer systems that store your money
are run. If I ever make a fortune, I will store it in gold bullion
under my bed.