Re: [Qemu-devel] [PATCH v3 0/5] QEMU:Xen stubdom vTPM for HVM virtual machine

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

On Mon, 19 Jan 2015, Stefano Stabellini wrote:
> Hi Quan,
> thanks for the update: this version is much much better than the
> previous one.
> 
> I am not familiar enough with QAPI, HMP and TPM to review the first and
> the last patches though.

I meant the first and the fourth. The last one is fine.


> Cheers,
> 
> Stefano
> 
> 
> On Tue, 30 Dec 2014, Quan Xu wrote:
> > *INTRODUCTION*
> > The goal of virtual Trusted Platform Module (vTPM) is to provide a TPM functionality to virtual machines (Fedora, Ubuntu, Redhat, Windows .etc). This allows programs to interact with a TPM in a virtual machine the same way they interact with a TPM on the physical system. Each virtual machine gets its own unique, emulated, software TPM. Each major component of vTPM is implemented as a stubdom, providing secure separation guaranteed by the hypervisor.
> > 
> > The vTPM stubdom is a Xen mini-OS domain that emulates a TPM for the virtual machine to use. It is a small wrapper around the Berlios TPM emulator. TPM commands are passed from mini-os TPM backend driver.
> > 
> > *ARCHITECTURE*
> > The architecture of stubdom vTPM for HVM virtual machine:
> > 
> >             +--------------------+
> >             | Windows/Linux DomU | ...
> >             |        |  ^        |
> >             |        v  |        |
> >             |  Qemu tpm1.2 Tis   |
> >             |        |  ^        |
> >             |        v  |        |
> >             | XenStubdoms backend|
> >             +--------------------+
> >                      |  ^
> >                      v  |
> >             +--------------------+
> >             |      XenDevOps     |
> >             +--------------------+
> >                      |  ^
> >                      v  |
> >             +--------------------+
> >             |  mini-os/tpmback   |
> >             |        |  ^        |
> >             |        v  |        |
> >             |   vtpm-stubdom     | ...
> >             |        |  ^        |
> >             |        v  |        |
> >             |  mini-os/tpmfront  |
> >             +--------------------+
> >                      |  ^
> >                      v  |
> >             +--------------------+
> >             |  mini-os/tpmback   |
> >             |        |  ^        |
> >             |        v  |        |
> >             |  vtpmmgr-stubdom   |
> >             |        |  ^        |
> >             |        v  |        |
> >             |  mini-os/tpm_tis   |
> >             +--------------------+
> >                      |  ^
> >                      v  |
> >             +--------------------+
> >             |    Hardware TPM    |
> >             +--------------------+
> > 
> > 
> > 
> >  * Windows/Linux DomU:
> >     The HVM based guest that wants to use a vTPM. There may be
> >     more than one of these.
> > 
> >  * Qemu tpm1.2 Tis:
> >     Implementation of the tpm1.2 Tis interface for HVM virtual
> >     machines. It is Qemu emulation device.
> > 
> >  * vTPM xenstubdoms driver:
> >     Qemu vTPM driver. This driver provides vtpm initialization
> >     and sending data and commends to a para-virtualized vtpm
> >     stubdom.
> > 
> >  * XenDevOps:
> >     Register Xen stubdom vTPM frontend driver, and transfer any
> >     request/repond between TPM xenstubdoms driver and Xen vTPM
> >     stubdom. Facilitate communications between Xen vTPM stubdom
> >     and vTPM xenstubdoms driver.
> > 
> >  * mini-os/tpmback:
> >     Mini-os TPM backend driver. The Linux frontend driver connects
> >     to this backend driver to facilitate communications between the
> >     Linux DomU and its vTPM. This driver is also used by vtpmmgr
> >     stubdom to communicate with vtpm-stubdom.
> > 
> >  * vtpm-stubdom:
> >     A mini-os stub domain that implements a vTPM. There is a
> >     one to one mapping between running vtpm-stubdom instances and
> >     logical vtpms on the system. The vTPM Platform Configuration
> >     Registers (PCRs) are all initialized to zero.
> > 
> >  * mini-os/tpmfront:
> >     Mini-os TPM frontend driver. The vTPM mini-os domain vtpm
> >     stubdom uses this driver to communicate with vtpmmgr-stubdom.
> >     This driver could also be used separately to implement a mini-os
> >     domain that wishes to use a vTPM of its own.
> > 
> >  * vtpmmgr-stubdom:
> >     A mini-os domain that implements the vTPM manager. There is only
> >     one vTPM manager and it should be running during the entire lifetime
> >     of the machine. vtpmmgr domain securely stores encryption keys for
> >     each of the vtpms and accesses to the hardware TPM to get the root of
> >     trust for the entire system.
> > 
> >  * mini-os/tpm_tis:
> >     Mini-os TPM version 1.2 TPM Interface Specification (TIS) driver.
> >     This driver used by vtpmmgr-stubdom to talk directly to the hardware
> >     TPM. Communication is facilitated by mapping hardware memory pages
> >     into vtpmmgr stubdom.
> > 
> >  * Hardware TPM: The physical TPM 1.2 that is soldered onto the motherboard.
> > 
> > --Changes in v3:
> >     -New xen_frontend.c file
> >     -Adjust the format of command line options
> >     -Move xenbus_switch_state() to xen_frontend.c
> >     -Move xen_stubdom_be() to xenstore_fe_read_be_str()
> >     -Move *_stubdom_*() to *_fe_*()
> >     -Move xen_stubdom_vtpm.c to xen_vtpm_frontend.c
> >     -Read Xen vTPM status via XenStore
> >     -Call vtpm_send() and vtpm_recv() directly.
> > 
> > --Changes in v2:
> >     -adding xen_fe_register() that handle any Xen PV frontend registration
> >     -remove a private structure 'QEMUBH'
> >     -change version number to 2.3 in qapi-schema.json
> >     -move hw/xen/xen_stubdom_vtpm.c to hw/tpm/xen_stubdom_vtpm.c
> > 
> > Quan Xu (5):
> >   Qemu-Xen-vTPM: Support for Xen stubdom vTPM command line options
> >   Qemu-Xen-vTPM: Xen frontend driver infrastructure
> >   Qemu-Xen-vTPM: Register Xen stubdom vTPM frontend driver
> >   Qemu-Xen-vTPM: Qemu vTPM xenstubdoms backen.
> >   Qemu-Xen-vTPM: QEMU machine class is initialized before tpm_init()
> > 
> >  configure                    |  14 ++
> >  hmp.c                        |   7 +
> >  hw/tpm/Makefile.objs         |   1 +
> >  hw/tpm/tpm_xenstubdoms.c     | 245 ++++++++++++++++++++++++++++++++
> >  hw/tpm/xen_vtpm_frontend.c   | 264 +++++++++++++++++++++++++++++++++++
> >  hw/xen/Makefile.objs         |   2 +-
> >  hw/xen/xen_backend.c         |  45 +++++-
> >  hw/xen/xen_frontend.c        | 323 +++++++++++++++++++++++++++++++++++++++++++
> >  include/hw/xen/xen_backend.h |  19 +++
> >  include/hw/xen/xen_common.h  |   6 +
> >  qapi-schema.json             |  19 ++-
> >  qemu-options.hx              |  13 +-
> >  tpm.c                        |   7 +-
> >  vl.c                         |  16 ++-
> >  xen-hvm.c                    |  16 +++
> >  15 files changed, 983 insertions(+), 14 deletions(-)
> >  create mode 100644 hw/tpm/tpm_xenstubdoms.c
> >  create mode 100644 hw/tpm/xen_vtpm_frontend.c
> >  create mode 100644 hw/xen/xen_frontend.c
> > 
> > -- 
> > 1.8.3.2
> > 
>