linux-kernel - Re: [PATCH v17 18/23] platform/x86: Intel SGX driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CALCETrV4UA5bn6dkq5aVycApx1ubq-rho_z=sHhxABbOSGZWMw@mail.gmail.com>
Date:   Wed, 28 Nov 2018 13:52:00 -0800
From:   Andy Lutomirski <luto@...capital.net>
To:     "Dr. Greg Wettstein" <greg@...ellic.com>
Cc:     Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>,
        Andrew Lutomirski <luto@...nel.org>, X86 ML <x86@...nel.org>,
        Platform Driver <platform-driver-x86@...r.kernel.org>,
        linux-sgx@...r.kernel.org, Dave Hansen <dave.hansen@...el.com>,
        "Christopherson, Sean J" <sean.j.christopherson@...el.com>,
        nhorman@...hat.com, npmccallum@...hat.com,
        "Ayoun, Serge" <serge.ayoun@...el.com>, shay.katz-zamir@...el.com,
        haitao.huang@...ux.intel.com,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        "Svahn, Kai" <kai.svahn@...el.com>, mark.shanahan@...el.com,
        Suresh Siddha <suresh.b.siddha@...el.com>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>,
        Darren Hart <dvhart@...radead.org>,
        Andy Shevchenko <andy@...radead.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v17 18/23] platform/x86: Intel SGX driver

On Tue, Nov 27, 2018 at 12:55 AM Dr. Greg <greg@...ellic.com> wrote:
> Since the thread has become a bit divergent I wanted to note that we
> have offered a proposal for a general policy management framework
> based on MRSIGNER values.  This framework is consistent with the SGX
> security model, ie. cryptographic rather then DAC based policy
> controls.  This framework also allows a much more flexible policy
> implementation that doesn't result in combinatoric issues.

Can you give a concrete explanation of a problem that your proposal
would solve?  As far as I can tell, it gets rid of a case in which an
unprivileged attacker who can run enclaves but hasn't compromised the
kernel can learn the PPID and other SGX-related permanent platform
identifiers, but it does nothing to prevent the same attacker from
learning non-SGX-related permanent identifiers, nor does it prevent
the attacker from using the Intel quoting enclave (unless configured
in a surprising way) and thus attesting to a remote system.

So what problem does it solve?