Re: [PATCH 1/3 v5] add a new ima hook and policy to measure the cmdline

[prakhar srivastava]

On Mon, May 13, 2019 at 9:56 AM Mimi Zohar <zohar@xxxxxxxxxxxxx> wrote:
>
> On Fri, 2019-05-10 at 15:37 -0700, Prakhar Srivastava wrote:
>
> > +/*
> > + * process_buffer_measurement - Measure the buffer passed to ima log.
>
> "passed to ima log" is unnecessary.
>
> > + * (Instead of using the file hash use the buffer hash).
>
> This comment, if needed, belongs in the text description area below,
> not here.
>
> > + * @buf - The buffer that needs to be added to the log
> > + * @size - size of buffer(in bytes)
> > + * @eventname - event name to be used for buffer.
>
> Missing are the other fields.
>
> > + *
> > + * The buffer passed is added to the ima log.
> > + *
> > + * On success return 0.
> > + * On error cases surface errors from ima calls.
>
> Only IMA-appraise returns errors to the caller.  There's no point in
> returning an error.
>
>
> > + */
> > +static int process_buffer_measurement(const void *buf, int size,
> > +                             const char *eventname, const struct cred *cred,
> > +                             u32 secid)
>
> This should be "static void".
>
> > +{
> > +
> > +     if (action & IMA_MEASURE)
> > +             ret = ima_store_template(entry, violation, NULL, buf, pcr);
> > +
> > +     if (action & IMA_AUDIT)
> > +             ima_audit_measurement(iint, event_data.filename);
>
> The cover letter and patch description say this patch set is limited
> to measuring the boot command line - IMA-measurement.
>  ima_audit_measurement() adds file hashes in the audit log, which can
> be used for security analytics and/or forensics.  This is part of IMA-
> audit.  The call to ima_audit_measurement() is inappropriate.
>
To clarify, in one of the previous versions you mentioned it
might be helpful to add audit.
I might have misunderstood you, but i will remove the
audit_measurement and make other corrections.
Thankyou for your feedback.

- Thanks,
Prakhar Srivastava
 Mimi