[Freeipa-devel] [RANT] --setattr validation is a minefield.

[Martin Kosek]

On Thu, 2012-05-10 at 15:19 +0200, Petr Viktorin wrote:
> On 04/10/2012 07:53 PM, Martin Kosek wrote:
> > On Tue, 2012-04-10 at 19:25 +0200, Petr Viktorin wrote:
> >> On 04/10/2012 07:07 PM, Martin Kosek wrote:
> >>> On Tue, 2012-04-10 at 17:03 +0200, Jan Cholasta wrote:
> >>>> On 10.4.2012 16:00, Petr Viktorin wrote:
> > [snip]
> >>>> Like you said above, we should either not validate --{set,add,del}attr
> >>>> or don't allow them on known attributes.
> >>>
> >>> IMHO, validating attributes we manage in the same way for both --setattr
> >>> and standard attrs is not that wrong. It is a good precaution, because
> >>> if we let an unvalidated value in, it can make even a bigger mess later
> >>> in our pre_callbacks or post_callbacks where we assume that at this
> >>> point everything is valid.
> >>
> >> Then we should validate *exactly* the same way, including not allowing
> >> no_update attributes to be updated.
> >
> > That makes some sense, I could agree with that.
> >
> 
> Now that I have a ticket on this 
> (https://fedorahosted.org/freeipa/ticket/2580), I would like to get some 
> wider agreement here.
> 
> The no_update/no_create attributes are mainly "enabled" flags 
> (ipaenabledflag, nsaccountlock, idnszoneactive), administrative 
> (krbprincipalname, ipauniqueid, ipacertificatesubjectbase), DNS record 
> type and data, and various virtual attributes.
> 
> If setattr etc. is disabled for all of these, it will mainly matter for 
> the "enabled" flags. To be honest I don't know why we only allow 
> modifying those through special commands.
> If there's some security reason for that, then setattr etc. should be 
> disabled for them; otherwise I think they should be changeable through 
> xyz-mod.

I am not aware of any security reasons why we use special commands for
enabling/disabling objects. I assume this is to make it different from
standard object attribute changes and make sure that user does not
disable the object "by accident" when doing a mod operation. Rob, maybe
you remember the reason for this interface....

But since we already have this approach, we should keep it and implement
missing "xyz-enable" and "xyz-disable" command so that user's using
*attr interface to play with enabled/disabled attributes can switch to
the specialized commands.

So far, I noticed that only DNS zone object misses the enable/disable
commands, I created a ticket to fix that:

https://fedorahosted.org/freeipa/ticket/2754

> Either way, setattr etc. should honor the no_update flags. Any objections?
> 

Nope - as long as ticket 2754 is fixed.

Martin