Re: [Qemu-devel] [PATCH v6 8/8] tpm: Added support for TPM emulator

[Stefan Berger]

On 07/18/2017 04:49 AM, Amarnath Valluri wrote:
> diff --git a/hw/tpm/Makefile.objs b/hw/tpm/Makefile.objs
> index 64cecc3..41f0b7a 100644
> --- a/hw/tpm/Makefile.objs
> +++ b/hw/tpm/Makefile.objs
> @@ -1,2 +1,3 @@
>   common-obj-$(CONFIG_TPM_TIS) += tpm_tis.o
>   common-obj-$(CONFIG_TPM_PASSTHROUGH) += tpm_passthrough.o tpm_util.o
> +common-obj-$(CONFIG_TPM_EMULATOR) += tpm_emulator.o tpm_util.o
> diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
> new file mode 100644
> index 0000000..c90914c
> --- /dev/null
> +++ b/hw/tpm/tpm_emulator.c
> @@ -0,0 +1,973 @@
> +/*
> + *  emulator TPM driver
> + *
> + *  Copyright (c) 2017 Intel Corporation
> + *  Author: Amarnath Valluri <address@hidden>
> + *
> + *  Copyright (c) 2010 - 2013 IBM Corporation
> + *  Authors:
> + *    Stefan Berger <address@hidden>
> + *
> + *  Copyright (C) 2011 IAIK, Graz University of Technology
> + *    Author: Andreas Niederl
> + *
> + * 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 "qemu/osdep.h"
> +#include "qemu/error-report.h"
> +#include "qemu/sockets.h"
> +#include "io/channel-socket.h"
> +#include "sysemu/tpm_backend.h"
> +#include "tpm_int.h"
> +#include "hw/hw.h"
> +#include "hw/i386/pc.h"
> +#include "tpm_util.h"
> +#include "tpm_ioctl.h"
> +#include "migration/migration.h"
> +#include "qapi/error.h"
> +
> +#include <fcntl.h>
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <stdio.h>
> +
> +#define DEBUG_TPM 0
> +
> +#define DPRINT(fmt, ...) do { \
> +    if (DEBUG_TPM) { \
> +        fprintf(stderr, fmt, ## __VA_ARGS__); \
> +    } \
> +} while (0);
> +
> +#define DPRINTF(fmt, ...) DPRINT("tpm-emulator: "fmt"\n", __VA_ARGS__)
> +
> +#define TYPE_TPM_EMULATOR "tpm-emulator"
> +#define TPM_EMULATOR(obj) \
> +    OBJECT_CHECK(TPMEmulator, (obj), TYPE_TPM_EMULATOR)
> +
> +static const TPMDriverOps tpm_emulator_driver;
> +
> +/* data structures */
> +typedef struct TPMEmulator {
> +    TPMBackend parent;
> +
> +    TPMEmulatorOptions *ops;
> +    QIOChannel *data_ioc;
> +    QIOChannel *ctrl_ioc;
> +    bool op_executing;
> +    bool op_canceled;
> +    bool child_running;
> +    TPMVersion tpm_version;
> +    ptm_cap caps; /* capabilities of the TPM */
> +    uint8_t cur_locty_number; /* last set locality */
> +    QemuMutex state_lock;
> +    Error *migration_blocker;
> +} TPMEmulator;
> +
> +#define TPM_DEFAULT_EMULATOR "swtpm"
> +#define TPM_DEFAULT_LOGLEVEL 5
> +#define TPM_EMULATOR_PIDFILE "/tmp/qemu-tpm.pid"

swtpm will write this file and remove it when it terminates. You may run 
into concurrency problems as well. I would extend this name with the pid 
of the QEMU process starting swtpm.

   Stefan