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Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager

From Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Newsgroups linux.kernel
Subject Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager
Date 2017-01-03 19:50 +0100
Message-ID <sVCjL-1Wi-17@gated-at.bofh.it> (permalink)
References (1 earlier) <sVdOp-19V-19@gated-at.bofh.it> <sViEq-4AZ-7@gated-at.bofh.it> <sViEq-4AZ-5@gated-at.bofh.it> <sVxN8-78b-19@gated-at.bofh.it> <sVAhX-xZ-3@gated-at.bofh.it>
Organization Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo

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On Tue, Jan 03, 2017 at 08:36:10AM -0800, James Bottomley wrote:
> On Tue, 2017-01-03 at 15:51 +0200, Jarkko Sakkinen wrote:
> > On Mon, Jan 02, 2017 at 01:40:48PM -0800, James Bottomley wrote:
> > > On Mon, 2017-01-02 at 21:33 +0200, Jarkko Sakkinen wrote:
> > > > On Mon, Jan 02, 2017 at 08:36:20AM -0800, James Bottomley wrote:
> > > > > On Mon, 2017-01-02 at 15:22 +0200, Jarkko Sakkinen wrote:
> > > > > > This patch set adds support for TPM spaces that provide a 
> > > > > > context for isolating and swapping transient objects. This 
> > > > > > patch set does not yet include support for isolating policy 
> > > > > > and HMAC sessions but it is trivial to add once the basic 
> > > > > > approach is settled (and that's why I created an RFC patch
> > > > > > set).
> > > > > 
> > > > > The approach looks fine to me.  The only basic query I have is 
> > > > > about the default: shouldn't it be with resource manager on 
> > > > > rather than off?  I can't really think of a use case that wants 
> > > > > the RM off (even if you're running your own, having another 
> > > > > doesn't hurt anything, and it's still required to share with in
> > > > > -kernel uses).
> > > > 
> > > > This is a valid question and here's a longish explanation.
> > > > 
> > > > In TPM2_GetCapability and maybe couple of other commands you can 
> > > > get handles in the response body. I do not want to have special 
> > > > cases in the kernel for response bodies because there is no a 
> > > > generic way to do the substitution. What's worse, new commands in 
> > > > the standard future revisions could have such commands requiring 
> > > > special cases. In addition, vendor specific commans could have 
> > > > handles in the response bodies.
> > > 
> > > OK, in general I buy this ... what you're effectively saying is 
> > > that we need a non-RM interface for certain management type
> > > commands.
> > 
> > Not only that.
> > 
> > Doing virtualization for commands like GetCapability is just a better
> > fit for doing in the user space. You could have a thin translation 
> > layer in your TSS library for example to handle these specific
> > messages.
> 
> Yes, we could do it that way too.  To be honest I can't see much use
> for getting the transient handles and all the other handles you'd be
> interested in aren't virtualized.
> 
> > > However, let me expand a bit on why I'm fretting about the non-RM 
> > > use case.  Right at the moment, we have a single TPM device which 
> > > you use for access to the kernel TPM.  The current tss2 just makes 
> > > direct use of this, meaning it has to have 0666 permissions.  This 
> > > means that any local user can simply DoS the TPM by running us out 
> > > of transient resources if they don't activate the RM.  If they get 
> > > a connection always via the RM, this isn't a worry.  Perhaps the 
> > > best way of fixing this is to expose two separate device nodes: one 
> > > raw to the TPM which we could keep at 0600 and one with an always 
> > > RM connection which we can set to 0666.  That would mean that 
> > > access to the non-RM connection is either root only or governed by
> > > a system set ACL.
> > 
> > I'm not sure about this. Why you couldn't have a very thin daemon 
> > that prepares the file descriptor and sends it through UDS socket to 
> > a client.
> 
> So I'm a bit soured on daemons from the trousers experience: tcsd
> crashed regularly and when it did it took all the TPM connections down
> irrecoverably.  I'm not saying we can't write a stateless daemon to fix
> most of the trousers issues, but I think it's valuable first to ask the
> question, "can we manage without a daemon at all?"  I actually think
> the answer is "yes", so I'm interested in seeing how far that line of
> research gets us.

This was not a good argument in the first place because you could also
use daemon with tpms0. We can ignore this.

> >   The non-RFC version will also have whitelisting ioctl for
> > further restricting the file descriptor to only specific TPM
> > commands.
> > 
> > This is also architecture I preseted in my LSS presentation and I 
> > think it makes sense especially when I add the whitelisting to the
> > pack.
> 
> Do you have a link to the presentation?  The Plumbers etherpad doesn't
> contain it.  I've been trying to work out whether a properly set up TPM
> actually does need any protections at all.  As far as I can tell, once
> you've set all the hierarchy authorities and the lockout one, you're
> pretty well protected.

http://events.linuxfoundation.org/sites/events/files/slides/201608-LinuxSecuritySummit-TPM.pdf

> > > James
> > 
> > I'm more dilated to keep things way they are now. I'll stick to that 
> > at least with the first non-RFC version and hopefully get the tpm2
> > -space.c part reviewed as I split that stuff to a separate commit.
> 
> Sure, we need the patch in an acceptable form first.  I'll keep
> worrying about the systems implications, but I can layer playing with
> those on top of what you do.
> 
> James

/Jarkko

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[PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-02 14:30 +0100
  [PATCH RFC 2/4] tpm: validate TPM 2.0 commands Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-02 14:30 +0100
    Re: [tpmdd-devel] [PATCH RFC 2/4] tpm: validate TPM 2.0 commands James Bottomley <jejb@linux.vnet.ibm.com> - 2017-01-04 19:30 +0100
    Re: [tpmdd-devel] [PATCH RFC 2/4] tpm: validate TPM 2.0 commands Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-04 19:50 +0100
  [PATCH RFC 3/4] tpm: export tpm2_flush_context_cmd Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-02 14:30 +0100
  [PATCH RFC 4/4] tpm: add the infrastructure for TPM space for TPM 2.0 Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-02 14:30 +0100
    Re: [PATCH RFC 4/4] tpm: add the infrastructure for TPM space for  TPM 2.0 Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-02 22:20 +0100
      Re: [PATCH RFC 4/4] tpm: add the infrastructure for TPM space for  TPM 2.0 Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-03 05:10 +0100
        Re: [PATCH RFC 4/4] tpm: add the infrastructure for TPM space for  TPM 2.0 Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-03 19:50 +0100
          Re: [PATCH RFC 4/4] tpm: add the infrastructure for TPM space for  TPM 2.0 Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-04 13:50 +0100
        Re: [PATCH RFC 4/4] tpm: add the infrastructure for TPM space for  TPM 2.0 Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-03 20:20 +0100
          Re: [PATCH RFC 4/4] tpm: add the infrastructure for TPM space for  TPM 2.0 Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-04 13:50 +0100
    Re: [tpmdd-devel] [PATCH RFC 4/4] tpm: add the infrastructure for  TPM    space for TPM 2.0 Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-09 23:20 +0100
  [PATCH RFC 1/4] tpm: migrate struct tpm_buf to struct tpm_chip Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-02 14:30 +0100
    Re: [PATCH RFC 1/4] tpm: migrate struct tpm_buf to struct tpm_chip Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-02 22:10 +0100
      Re: [PATCH RFC 1/4] tpm: migrate struct tpm_buf to struct tpm_chip Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-03 05:10 +0100
        Re: [PATCH RFC 1/4] tpm: migrate struct tpm_buf to struct tpm_chip Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-03 20:20 +0100
          Re: [PATCH RFC 1/4] tpm: migrate struct tpm_buf to struct tpm_chip Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-04 13:40 +0100
  Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <James.Bottomley@HansenPartnership.com> - 2017-01-02 17:40 +0100
    Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <James.Bottomley@HansenPartnership.com> - 2017-01-02 22:50 +0100
      Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <jejb@linux.vnet.ibm.com> - 2017-01-03 06:30 +0100
        Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-03 14:50 +0100
          Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <jejb@linux.vnet.ibm.com> - 2017-01-03 17:20 +0100
            Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-03 19:40 +0100
              Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-03 20:20 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <jejb@linux.vnet.ibm.com> - 2017-01-04 02:30 +0100
        Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-03 23:00 +0100
          Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-04 14:10 +0100
            Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-04 18:00 +0100
        Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Andy Lutomirski <luto@kernel.org> - 2017-01-04 06:50 +0100
          Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-04 14:10 +0100
      Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-03 15:00 +0100
        Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <James.Bottomley@HansenPartnership.com> - 2017-01-03 17:40 +0100
          Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-03 19:50 +0100
          Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-03 22:50 +0100
            Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <James.Bottomley@HansenPartnership.com> - 2017-01-03 23:50 +0100
              Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-04 01:20 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <James.Bottomley@HansenPartnership.com> - 2017-01-04 01:40 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-04 02:00 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-04 14:00 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <James.Bottomley@HansenPartnership.com> - 2017-01-04 16:00 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <James.Bottomley@HansenPartnership.com> - 2017-01-04 20:10 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-04 20:30 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-04 20:30 +0100
            Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-04 00:30 +0100
            Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-04 13:50 +0100
            Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Ken Goldman <kgoldman@us.ibm.com> - 2017-01-04 15:00 +0100
    Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-03 05:10 +0100
    Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-03 22:40 +0100
      Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <James.Bottomley@HansenPartnership.com> - 2017-01-03 23:10 +0100
  RE: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager "Fuchs, Andreas" <andreas.fuchs@sit.fraunhofer.de> - 2017-01-05 17:10 +0100
    Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-05 18:30 +0100
      Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <jejb@linux.vnet.ibm.com> - 2017-01-05 19:10 +0100
        Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Andreas Fuchs <andreas.fuchs@sit.fraunhofer.de> - 2017-01-06 09:50 +0100
      Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <jejb@linux.vnet.ibm.com> - 2017-01-05 19:40 +0100
        Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-05 21:00 +0100
          Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <jejb@linux.vnet.ibm.com> - 2017-01-05 21:00 +0100
            Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-05 23:30 +0100
              Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-06 01:00 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <jejb@linux.vnet.ibm.com> - 2017-01-06 01:40 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Andreas Fuchs <andreas.fuchs@sit.fraunhofer.de> - 2017-01-06 10:10 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-06 20:20 +0100
                Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jason Gunthorpe <jgunthorpe@obsidianresearch.com> - 2017-01-06 20:10 +0100
              Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager James Bottomley <jejb@linux.vnet.ibm.com> - 2017-01-06 02:40 +0100
          Re: [PATCH RFC 0/4] RFC: in-kernel resource manager Ken Goldman <kgoldman@us.ibm.com> - 2017-01-10 20:20 +0100
    Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> - 2017-01-09 23:40 +0100
      Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager Andreas Fuchs <andreas.fuchs@sit.fraunhofer.de> - 2017-01-11 11:10 +0100

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