Monday, April 21, 2008

Where's my Primary Administrator gone?

One neat aspect of Solaris is RBAC, which allows you to control which actions users can perform.

A particularly blunt instrument is the 'Primary Administrator' profile. If you're a Primary Administrator, then you are effectively root - in that you can use pfexec to assume the privileges of the root account (or role).

In Indiana, for example, root is (normally) a role and the account you create at install is set up as a Primary Administrator. It's very convenient.

So I decided to implement the same mechanism on my home machines (and use RBAC to let my children do extra things without having to pester dad).

Which failed, big time. It's really easy, you just use usermod to add a profile to an account:

usermod -P 'Primary Administrator' user_name

at which point Solaris thumbed its nose at me.

UX: usermod: ERROR: Primary Administrator is not a valid profile name. Choose another.

I decided to dig a little deeper, and then you discover that the way these profiles find their way onto the system is (ahem) strange.

The profiles are defined in some files that live in /etc/security - auth_attr, exec_attr, and prof_attr - and then /etc/user_attr controls what is assigned to users. So where do these files come from?

It turns out that different packages stick their own entries in. If you start looking around the Solaris media, then go into Solaris_XX/Product and look for */reloc/etc/security/exec_attr (and the same for prof_attr and auth_attr). These are the files that get merged into the master copy by some funky class action script. (There are things about IPS that I don't agree with, but its plan of getting rid of all these way out scripts is something that has to be good.)

OK, so looking in those files, and the Primary Administrator is delivered by the SUNWwbcor package. What's that? "Solaris WBEM Services (root)".

No wonder I hadn't got the profile. I never install WBEM or anything to do with it. Systems are much better off without it (and I couldn't ever see myself installing it on something like a home system, or indeed any system where Primary Administrator might be used). But, if you don't install that package then you're going to have to install the profile yourself. Something like the following in the Product directory on the media should do it:

cat SUNWwbcor/reloc/etc/security/auth_attr >> /etc/security/auth_attr
cat SUNWwbcor/reloc/etc/security/exec_attr >> /etc/security/exec_attr
cat SUNWwbcor/reloc/etc/security/prof_attr >> /etc/security/prof_attr

1 comment:

Anonymous said...

Hah! Ya, we ran into this at Joyent about 6 months ago. Was a shock to us too. :)