Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20220302111404.193900-1-roberto.sassu@huawei.com>
 <20220302222056.73dzw5lnapvfurxg@ast-mbp.dhcp.thefacebook.com>
 <fe1d17e7e7d4b5e4cdeb9f96f5771ded23b7c8f0.camel@linux.ibm.com>
 <CACYkzJ4fmJ4XtC6gx6k_Gjq0n5vjSJyq=L--H-Eho072HJoywA@mail.gmail.com>
 <04d878d4b2441bb8a579a4191d8edc936c5a794a.camel@linux.ibm.com>
 <CACYkzJ5RNDV582yt1xCZ8AQUW6v_o0Dtoc_XAQN1GXnoOmze6Q@mail.gmail.com>
 <b6bf8463c1b370a5b5c9987ae1312fd930d36785.camel@linux.ibm.com>
 <CAADnVQKfh3Z1DXJ3PEjFheQWEDFOKQjuyx+pkvqe6MXEmo7YHQ@mail.gmail.com> <40db9f74fd3c9c7b660e3a203c5a6eda08736d5b.camel@linux.ibm.com>
In-Reply-To: <40db9f74fd3c9c7b660e3a203c5a6eda08736d5b.camel@linux.ibm.com>
From:   KP Singh <kpsingh@kernel.org>
Date:   Mon, 7 Mar 2022 14:17:55 +0100
Message-ID: <CACYkzJ65D2OZKrEbrCS32+FsQ3BVzs1zQcRQSLnaNQHYTjZFBA@mail.gmail.com>
Subject: Re: [PATCH v3 0/9] bpf-lsm: Extend interoperability with IMA
To:     Mimi Zohar <zohar@linux.ibm.com>
Cc:     Alexei Starovoitov <alexei.starovoitov@gmail.com>,
        Roberto Sassu <roberto.sassu@huawei.com>,
        Shuah Khan <shuah@kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Yonghong Song <yhs@fb.com>,
        Florent Revest <revest@chromium.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-integrity <linux-integrity@vger.kernel.org>,
        LSM List <linux-security-module@vger.kernel.org>,
        "open list:KERNEL SELFTEST FRAMEWORK" 
        <linux-kselftest@vger.kernel.org>, bpf <bpf@vger.kernel.org>,
        Network Development <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Florent Revest <revest@google.com>,
        Kees Cook <keescook@chromium.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Mon, Mar 7, 2022 at 3:57 AM Mimi Zohar <zohar@linux.ibm.com> wrote:
>
> On Thu, 2022-03-03 at 14:39 -0800, Alexei Starovoitov wrote:
>
> > . There is no such thing as "eBPF modules". There are BPF programs.
> > They cannot be signed the same way as kernel modules.
> > We've been working on providing a way to sign them for more
> > than a year now. That work is still ongoing.
> >
> > . IMA cannot be used for integrity check of BPF programs for the same
> > reasons why kernel module like signing cannot be used.
>
> I assume the issue isn't where the signature is stored (e.g. appended,
> xattr), but of calculating the hash.  Where is the discussion taking

This has the relevant background: https://lwn.net/Articles/853489/

We had some more discussions in one of our BSC meeting:

https://github.com/ebpf-io/bsc/blob/master/minutes.md

and we expect the discussions to continue over conferences this year
 (e.g. LSF/MM/BPF, Linux Plumbers). As I mentioned on another thread
we don't have to wait for conferences and we can discuss this in the BPF
office hours. Please feel free to add an agenda at:

https://docs.google.com/spreadsheets/d/1LfrDXZ9-fdhvPEp_LHkxAMYyxxpwBXjywWa0AejEveU/edit#gid=0

(best is to give some notice so that interested folks can join).

> place?   Are there any summaries of what has been discussed?
>
> FYI, IMA isn't limited to measuring files.  Support was added for
> buffer measurements (e.g kexec boot command line, certificates) and
> measuring kernel critical data (e.g. SELinux in memory policy & state,
> device mapper).

Nice. I need to look at how this is implemented.

- KP

>
> thanks,
>
> Mimi
>