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Subject: Re: [PATCH v3 4/5] LSM: Define SELinux function to measure security
 state
From:   Mimi Zohar <zohar@linux.ibm.com>
To:     Stephen Smalley <stephen.smalley.work@gmail.com>,
        Lakshmi Ramasubramanian <nramas@linux.microsoft.com>,
        Tyler Hicks <tyhicks@canonical.com>,
        Prakhar Srivastava <prsriva02@gmail.com>
Cc:     Casey Schaufler <casey@schaufler-ca.com>,
        James Morris <jmorris@namei.org>,
        linux-integrity@vger.kernel.org,
        SElinux list <selinux@vger.kernel.org>,
        LSM List <linux-security-module@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Date:   Mon, 20 Jul 2020 13:26:52 -0400
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On Mon, 2020-07-20 at 13:06 -0400, Stephen Smalley wrote:
> 
> 
> I applied the patch series on top of the next-integrity branch, added
> measure func=LSM_STATE to ima-policy, and booted that kernel.  I get
> the following entries in ascii_runtime_measurements, but seemingly
> missing the final field:
> 
> 10 8a09c48af4f8a817f59b495bd82971e096e2e367 ima-ng
> sha256:21c3d7b09b62b4d0b3ed15ba990f816b94808f90b76787bfae755c4b3a44cd24
> selinux-state
> 10 e610908931d70990a2855ddb33c16af2d82ce56a ima-ng
> sha256:c8898652afd5527ef4eaf8d85f5fee1d91fcccee34bc97f6e55b96746bedb318
> selinux-policy-hash
> 
> Thus, I cannot verify. What am I missing?

Missing is "template=ima-buf" on the policy rule.

Tyler's patch set just added some support for verifying the policy.
 Refer to ima_validate_rule().  There are still some things missing.
 For example, nayna noticed that making sure that asymmetric key
support is enabled.  Another example is requiring "template=" for any
of the buffer measurements.  Template names can be defined
dynamically, so it will need to support either format:

measure func=KEXEC_CMDLINE template=ima-buf 
measure func=KEXEC_CMDLINE template=d-ng|n-ng|buf

Mimi