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From:   prakhar srivastava <prsriva02@gmail.com>
Date:   Mon, 13 May 2019 21:53:44 -0700
Message-ID: <CAEFn8qJNzG5scBcdVbrXpY7ZEbku+yNbMZn3M=JUW8nNZbGKoQ@mail.gmail.com>
Subject: Re: [PATCH 1/3 v5] add a new ima hook and policy to measure the cmdline
To:     Mimi Zohar <zohar@linux.ibm.com>
Cc:     linux-integrity@vger.kernel.org,
        inux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org,
        ebiederm@xmission.com, vgoyal@redhat.com,
        Prakhar Srivastava <prsriva@microsoft.com>
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On Mon, May 13, 2019 at 9:56 AM Mimi Zohar <zohar@linux.ibm.com> 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