Re: [PATCH] audit: add containerid support for IMA-audit

[Mimi Zohar <zohar@linux.vnet.ibm.com>]

On Fri, 2018-05-18 at 11:56 -0400, Richard Guy Briggs wrote:
> On 2018-05-18 10:39, Mimi Zohar wrote:
> > On Fri, 2018-05-18 at 09:54 -0400, Stefan Berger wrote:
> > > On 05/18/2018 08:53 AM, Mimi Zohar wrote:
> > 
> > [..]
> > 
> > > >>>> If so, which ones? We could probably refactor the current
> > > >>>> integrity_audit_message() and have ima_parse_rule() call into it to get
> > > >>>> those fields as well. I suppose adding new fields to it wouldn't be
> > > >>>> considered breaking user space?
> > > >>> Changing the order of existing fields or inserting fields could break
> > > >>> stuff and is strongly discouraged without a good reason, but appending
> > > >>> fields is usually the right way to add information.
> > > >>>
> > > >>> There are exceptions, and in this case, I'd pick the "more standard" of
> > > >>> the formats for AUDIT_INTEGRITY_RULE (ima_audit_measurement?) and stick
> > > >>> with that, abandoning the other format, renaming the less standard
> > > >>> version of the record (ima_parse_rule?) and perhpas adopting that
> > > >>> abandonned format for the new record type while using
> > > >>> current->audit_context.
> > > > This sounds right, other than "type=INTEGRITY_RULE" (1805) for
> > > > ima_audit_measurement().  Could we rename type=1805 to be
> > > 
> > > So do we want to change both? I thought that what 
> > > ima_audit_measurement() produces looks ok but may not have a good name 
> > > for the 'type'. Now in this case I would not want to 'break user space'.
> > > The only change I was going to make was to what ima_parse_rule() produces.
> > 
> > The only change for now is separating the IMA policy rules from the
> > IMA-audit messages.
> > 
> > Richard, when the containerid is appended to the IMA-audit messages,
> > would we make the audit type name change then?
> 
> No, go ahead and make the change now.  I'm expecting that the
> containerid record will just be another auxiliary record and should not
> affect you folks.

To summarize, we need to disambiguate the 1805, as both
ima_parse_rule() and ima_audit_measurement() are using the same number
with different formats.  The main usage of 1805 that we are aware of
is ima_audit_measurement().  Yet the "type=" name for
ima_audit_measurement() should be INTEGRITY_IMA_AUDIT, not
INTEGRITY_RULE.

option 1: breaks both uses
1805 - INTEGRITY_IMA_AUDIT - ima_audit_measurement()
1806 - INTEGRITY_POLICY_RULE - ima_parse_rule()

option 2: breaks the most common usage
1805 - INTEGRITY_RULE - ima_parse_rule()
1806 - INTEGRITY_IMA_AUDIT - ima_audit_measurement()

option 3: leaves the most common usage with the wrong name, and breaks
the other less common usage
1805 - INTEGRITY_RULE - ima_audit_measurement()
1806 - INTEGRITY_POLICY_RULE - ima_parse_rule()

So option 3 is the best option?

Mimi