[PATCH v3] IMA: Add audit log for failure conditions

[Mimi Zohar]

On Tue, 2020-06-09 at 10:00 -0700, Lakshmi Ramasubramanian wrote:
> On 6/9/20 9:43 AM, Steve Grubb wrote:
> 
> >> The number in parenthesis is the error code (such as ENOMEM, EINVAL,
> >> etc.) IMA uses this format for reporting TPM errors in one of the audit
> >> messages (In ima_add_template_entry()). I followed the same pattern.
> >>
> >> Would it be better if the value for "cause" is formatted as
> >>
> >>      cause=hashing_error_-22
> >>
> >>      cause=alloc_entry_-12
> > 
> > Neither fit the name=value style that all other events follow. What would fit
> > the style is something like this:
> > 
> > cause=hashing_error  errno=-22
> >   
> > cause=alloc_entry errno=-12
> > 
> > Would this be OK? Also, errno is only to illustrate. You can name it
> > something else as long as there are no use case collisions with our
> > dictionary of field names.
> > 
> > https://github.com/linux-audit/audit-documentation/blob/master/specs/fields/
> > field-dictionary.csv
> 
> I am fine with this.
> 
> "errno" is currently not listed in the dictionary of audit message field 
> names (Thanks for the pointer to this one Steve)
> 
> Mimi - please let me know if you have any concerns with adding the 
> "result" code in "errno" field in integrity_audit_msg().
> 
> Sample message:
> 
> [    8.051937] audit: type=1804 audit(1591633422.365:8): pid=1 uid=0 
> auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 
> op=measuring_keys cause=hashing_error errno=-22 comm="systemd" 
> name=".builtin_trusted_keys" res=0

Yes, that's fine.

Mimi