From: Vivek Goyal <vgoyal@redhat.com>
Subject: Re: [RFC 1/1] ima: digital signature verification using asymmetric
 keys
Date: Tue, 29 Jan 2013 11:58:53 -0500
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Cc: "Kasatkin, Dmitry" <dmitry.kasatkin@intel.com>,
	dhowells@redhat.com, jmorris@namei.org,
	linux-security-module@vger.kernel.org,
	linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org
To: Mimi Zohar <zohar@linux.vnet.ibm.com>
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On Mon, Jan 28, 2013 at 08:48:55PM -0500, Mimi Zohar wrote:

[..]
> > Also given the fact that we allow loading policy from initramfs, root
> > can rebuild initramfs and change the policy which takes effect over next
> > reboot. So in priciple this works only when we are trying to impose some
> > policy on non-root users?
> 
> The assumption has always been that the initramfs would be measured, for
> trusted boot, and appraised, for secure boot, before being executed.

Hi Mimi,

Ok. So for trusted boot, if initramfs is changed it will be detected. For
secureboot, atleast right now initramfs is not signed and appraised. But
I guess it could be added. 

But initramfs is generated by installer and installer does not have
private keys to sign it. So distributions could not sign initramfs.

Thanks
Vivek