On Fri, Mar 11, 2016 at 09:51:03PM -0500, Stefan Berger wrote:
> This patch implements a proxy driver for supporting multiple emulated TPMs
> in a system.
>
> The driver implements a device /dev/vtpmx that is used to created
> a client device pair /dev/tpmX (e.g., /dev/tpm10) and a server side that
> is accessed using a file descriptor returned by an ioctl.
> The device /dev/tpmX is the usual TPM device created by the core TPM
> driver. Applications or kernel subsystems can send TPM commands to it
> and the corresponding server-side file descriptor receives these
> commands and delivers them to an emulated TPM.
With my test script [1] running on QEMU and TPM 2.0 simulator running on the
host side I get this:
$ python tpm2-simulator-vtpm --host=10.0.2.2
cmd
80 01 00 00 00 0c 00 00 01 44 00 00
rsp
80 01 00 00 00 0a 00 00 00 00
Traceback (most recent call last):
File "tpm2-simulator-vtpm", line 85, in
main()
File "tpm2-simulator-vtpm", line 80, in main
resp = client.send_cmd(stream)
File "/home/tpmdd/tpm2-scripts/tpm2.py", line 454, in send_cmd
rsp = self.simulator.send_cmd(cmd)
File "/home/tpmdd/tpm2-scripts/tpm2.py", line 436, in send_cmd
raise SimulatorError("Empty response")
tpm2.SimulatorError: Empty response
However, the process does not exit before the read call expires:
$ python tpm2-list-handles
Traceback (most recent call last):
File "tpm2-list-handles", line 61, in
main()
File "tpm2-list-handles", line 51, in main
handles += client.get_cap(tpm2.TPM2_CAP_HANDLES, tpm2.HR_LOADED_SESSION)
File "/home/tpmdd/tpm2-scripts/tpm2.py", line 782, in get_cap
next_handles, more_data = self.__get_cap_cnt(cap, pt, 1)
File "/home/tpmdd/tpm2-scripts/tpm2.py", line 766, in __get_cap_cnt
rsp = self.send_cmd(cmd)[10:]
File "/home/tpmdd/tpm2-scripts/tpm2.py", line 458, in send_cmd
rsp = f.read()
IOError: [Errno 62] Timer expired
The server side stays stuck unti this happens.
[1] git://git.infradead.org/users/jjs/tpm2-scripts.git
/Jarkko
> Signed-off-by: Stefan Berger
> CC: linux-ker...@vger.kernel.org
> CC: linux-doc@vger.kernel.org
> CC: linux-...@vger.kernel.org
> ---
> drivers/char/tpm/Kconfig | 10 +
> drivers/char/tpm/Makefile | 1 +
> drivers/char/tpm/tpm_vtpm_proxy.c | 567
> ++
> include/uapi/linux/Kbuild | 1 +
> include/uapi/linux/vtpm_proxy.h | 42 +++
> 5 files changed, 621 insertions(+)
> create mode 100644 drivers/char/tpm/tpm_vtpm_proxy.c
> create mode 100644 include/uapi/linux/vtpm_proxy.h
>
> diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig
> index 3b84a8b..0eac596 100644
> --- a/drivers/char/tpm/Kconfig
> +++ b/drivers/char/tpm/Kconfig
> @@ -122,5 +122,15 @@ config TCG_CRB
> from within Linux. To compile this driver as a module, choose
> M here; the module will be called tpm_crb.
>
> +config TCG_VTPM_PROXY
> + tristate "VTPM Proxy Interface"
> + depends on TCG_TPM
> + ---help---
> + This driver proxies for an emulated TPM (vTPM) running in userspace.
> + A device /dev/vtpmx is provided that creates a device pair
> + /dev/vtpmX and a server-side file descriptor on which the vTPM
> + can receive commands.
> +
> +
> source "drivers/char/tpm/st33zp24/Kconfig"
> endif # TCG_TPM
> diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
> index 56e8f1f..98de5e6 100644
> --- a/drivers/char/tpm/Makefile
> +++ b/drivers/char/tpm/Makefile
> @@ -23,3 +23,4 @@ obj-$(CONFIG_TCG_IBMVTPM) += tpm_ibmvtpm.o
> obj-$(CONFIG_TCG_TIS_ST33ZP24) += st33zp24/
> obj-$(CONFIG_TCG_XEN) += xen-tpmfront.o
> obj-$(CONFIG_TCG_CRB) += tpm_crb.o
> +obj-$(CONFIG_TCG_VTPM_PROXY) += tpm_vtpm_proxy.o
> diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c
> b/drivers/char/tpm/tpm_vtpm_proxy.c
> new file mode 100644
> index 000..d73944e
> --- /dev/null
> +++ b/drivers/char/tpm/tpm_vtpm_proxy.c
> @@ -0,0 +1,567 @@
> +/*
> + * Copyright (C) 2015, 2016 IBM Corporation
> + *
> + * Author: Stefan Berger
> + *
> + * Maintained by:
> + *
> + * Device driver for vTPM (vTPM proxy driver)
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation, version 2 of the
> + * License.
> + *
> + */
> +
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +
> +#include "tpm.h"
> +
> +#define VTPM_PROXY_REQ_COMPLETE_FLAG BIT(0)
> +
> +struct proxy_dev {
> + struct tpm_chip *chip;
> +
> + u32 flags; /* public API flags */
> +
> + wait_queue_head_t wq;
> +
> + struct mutex buf_lock; /* protect buffer and flags */
> +
> + long state; /* internal state */
> +#define STATE_OPENED_FLAGBIT(0)
> +#define STATE_WAIT_RESPONSE_FLAG BIT(1) /* waiting for emulator respons
