qemu-patch-raspberry4/tpm/tpm_backend.c
Stefan Berger 4549a8b7ee Add a TPM Passthrough backend driver implementation
This patch is based of off version 9 of Stefan Berger's patch series
  "QEMU Trusted Platform Module (TPM) integration"
and adds a new backend driver for it.

This patch adds a passthrough backend driver for passing commands sent to the
emulated TPM device directly to a TPM device opened on the host machine.
Thus it is possible to use a hardware TPM device in a system running on QEMU,
providing the ability to access a TPM in a special state (e.g. after a Trusted
Boot).

This functionality is being used in the acTvSM Trusted Virtualization Platform
which is available on [1].

Usage example:
  qemu-system-x86_64 -tpmdev passthrough,id=tpm0,path=/dev/tpm0 \
                     -device tpm-tis,tpmdev=tpm0 \
                     -cdrom test.iso -boot d

Some notes about the host TPM:
The TPM needs to be enabled and activated. If that's not the case one
has to go through the BIOS/UEFI and enable and activate that TPM for TPM
commands to work as expected.
It may be necessary to boot the kernel using tpm_tis.force=1 in the boot
command line or 'modprobe tpm_tis force=1' in case of using it as a module.

Regards,
Andreas Niederl, Stefan Berger

[1] http://trustedjava.sourceforge.net/

Signed-off-by: Andreas Niederl <andreas.niederl@iaik.tugraz.at>
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Reviewed-by: Joel Schopp <jschopp@linux.vnet.ibm.com>
Message-id: 1361987275-26289-6-git-send-email-stefanb@linux.vnet.ibm.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-12 13:40:55 -05:00

59 lines
1.9 KiB
C

/*
* common TPM backend driver functions
*
* Copyright (c) 2012-2013 IBM Corporation
* Authors:
* Stefan Berger <stefanb@us.ibm.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>
*/
#include "tpm/tpm.h"
#include "qemu/thread.h"
#include "tpm_backend.h"
void tpm_backend_thread_deliver_request(TPMBackendThread *tbt)
{
g_thread_pool_push(tbt->pool, (gpointer)TPM_BACKEND_CMD_PROCESS_CMD, NULL);
}
void tpm_backend_thread_create(TPMBackendThread *tbt,
GFunc func, gpointer user_data)
{
if (!tbt->pool) {
tbt->pool = g_thread_pool_new(func, user_data, 1, TRUE, NULL);
g_thread_pool_push(tbt->pool, (gpointer)TPM_BACKEND_CMD_INIT, NULL);
}
}
void tpm_backend_thread_end(TPMBackendThread *tbt)
{
if (tbt->pool) {
g_thread_pool_push(tbt->pool, (gpointer)TPM_BACKEND_CMD_END, NULL);
g_thread_pool_free(tbt->pool, FALSE, TRUE);
tbt->pool = NULL;
}
}
void tpm_backend_thread_tpm_reset(TPMBackendThread *tbt,
GFunc func, gpointer user_data)
{
if (!tbt->pool) {
tpm_backend_thread_create(tbt, func, user_data);
} else {
g_thread_pool_push(tbt->pool, (gpointer)TPM_BACKEND_CMD_TPM_RESET,
NULL);
}
}