From: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Subject: Re: [PATCH 6/6] ima: Support appended signatures for appraisal
Date: Thu, 27 Apr 2017 18:41:35 -0300
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Cc: kbuild test robot <lkp@intel.com>, kbuild-all@01.org,
        LSM <linux-security-module@vger.kernel.org>,
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        kernel <linux-kernel@vger.kernel.org>,
        Mimi Zohar <zohar@linux.vnet.ibm.com>,
        Dmitry Kasatkin <dmitry.kasatkin@gmail.com>,
        David Howells <dhowells@redhat.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        "David S. Miller" <davem@davemloft.net>,
        Claudio Carvalho <cclaudio@linux.vnet.ibm.com>
To: Mehmet Kayaalp <mkayaalp@linux.vnet.ibm.com>
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Am Mittwoch, 26. April 2017, 18:18:34 BRT schrieb Mehmet Kayaalp:
> > On Apr 20, 2017, at 7:41 PM, Thiago Jung Bauermann
> > <bauerman@linux.vnet.ibm.com> wrote:
> > 
> > This patch introduces the appended_imasig keyword to the IMA policy syntax
> > to specify that a given hook should expect the file to have the IMA
> > signature appended to it. Here is how it can be used in a rule:
> > 
> > appraise func=KEXEC_KERNEL_CHECK appraise_type=appended_imasig
> > appraise func=KEXEC_KERNEL_CHECK appraise_type=appended_imasig|imasig
> > 
> > In the second form, IMA will accept either an appended signature or a
> > signature stored in the extended attribute. In that case, it will first
> > check whether there is an appended signature, and if not it will read it
> > from the extended attribute.
> > 
> > The format of the appended signature is the same used for signed kernel
> > modules. This means that the file can be signed with the scripts/sign-file
> 
> > tool, with a command line such as this:
> I would suggest naming the appraise_type as modsig (or some variant) to
> clarify that the format is defined by how module signatures are handled.
> Maybe we'd like to define a different appended/inline signature format for
> IMA in the future.

I like the suggestion. Would that mean that we will keep refering to it as 
"module signature format", and thus nothing changes in patch 5?

-- 
Thiago Jung Bauermann
IBM Linux Technology Center