* [PATCH v5 08/11] tpm: Driver for supporting multiple emulated TPMs
[not found] <1457353514-2509-1-git-send-email-stefanb@linux.vnet.ibm.com>
@ 2016-03-07 12:25 ` Stefan Berger
2016-03-07 12:25 ` [PATCH v5 09/11] tpm: Initialize TPM and get durations and timeouts Stefan Berger
2016-03-07 12:25 ` [PATCH v5 10/11] tpm: Add documentation for the tpm_vtpm device driver Stefan Berger
2 siblings, 0 replies; 3+ messages in thread
From: Stefan Berger @ 2016-03-07 12:25 UTC (permalink / raw)
To: tpmdd-devel
Cc: jarkko.sakkinen, jgunthorpe, Stefan Berger, linux-kernel,
linux-doc, linux-api
This patch implements a 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.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
CC: linux-kernel@vger.kernel.org
CC: linux-doc@vger.kernel.org
CC: linux-api@vger.kernel.org
---
drivers/char/tpm/Kconfig | 10 +
drivers/char/tpm/Makefile | 1 +
drivers/char/tpm/tpm_vtpm.c | 566 ++++++++++++++++++++++++++++++++++++++++++++
include/uapi/linux/Kbuild | 1 +
include/uapi/linux/vtpm.h | 41 ++++
5 files changed, 619 insertions(+)
create mode 100644 drivers/char/tpm/tpm_vtpm.c
create mode 100644 include/uapi/linux/vtpm.h
diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig
index 3b84a8b..4c4e843 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
+ tristate "VTPM Interface"
+ depends on TCG_TPM
+ ---help---
+ This driver supports 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..1a409c57 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) += tpm_vtpm.o
diff --git a/drivers/char/tpm/tpm_vtpm.c b/drivers/char/tpm/tpm_vtpm.c
new file mode 100644
index 0000000..245ce91
--- /dev/null
+++ b/drivers/char/tpm/tpm_vtpm.c
@@ -0,0 +1,566 @@
+/*
+ * Copyright (C) 2015, 2016 IBM Corporation
+ *
+ * Author: Stefan Berger <stefanb@us.ibm.com>
+ *
+ * Maintained by: <tpmdd-devel@lists.sourceforge.net>
+ *
+ * Device driver for vTPM.
+ *
+ * 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 <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+#include <linux/wait.h>
+#include <linux/miscdevice.h>
+#include <linux/vtpm.h>
+#include <linux/file.h>
+#include <linux/anon_inodes.h>
+#include <linux/poll.h>
+#include <linux/compat.h>
+
+#include "tpm.h"
+
+#define VTPM_REQ_COMPLETE_FLAG BIT(0)
+
+struct vtpm_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_FLAG BIT(0)
+#define STATE_WAIT_RESPONSE_FLAG BIT(1) /* waiting for emulator response */
+
+ size_t req_len; /* length of queued TPM request */
+ size_t resp_len; /* length of queued TPM response */
+ u8 buffer[TPM_BUFSIZE]; /* request/response buffer */
+};
+
+
+static void vtpm_delete_device(struct vtpm_dev *vtpm_dev);
+
+/*
+ * Functions related to 'server side'
+ */
+
+/**
+ * vtpm_fops_read - Read TPM commands on 'server side'
+ *
+ * Return value:
+ * Number of bytes read or negative error code
+ */
+static ssize_t vtpm_fops_read(struct file *filp, char __user *buf,
+ size_t count, loff_t *off)
+{
+ struct vtpm_dev *vtpm_dev = filp->private_data;
+ size_t len;
+ int sig, rc;
+
+ sig = wait_event_interruptible(vtpm_dev->wq, vtpm_dev->req_len != 0);
+ if (sig)
+ return -EINTR;
+
+ mutex_lock(&vtpm_dev->buf_lock);
+
+ len = vtpm_dev->req_len;
+
+ if (count < len) {
+ mutex_unlock(&vtpm_dev->buf_lock);
+ pr_debug("Invalid size in recv: count=%zd, req_len=%zd\n",
+ count, len);
+ return -EIO;
+ }
+
+ rc = copy_to_user(buf, vtpm_dev->buffer, len);
+ memset(vtpm_dev->buffer, 0, len);
+ vtpm_dev->req_len = 0;
+
+ if (!rc)
+ vtpm_dev->state |= STATE_WAIT_RESPONSE_FLAG;
+
+ mutex_unlock(&vtpm_dev->buf_lock);
+
+ if (rc)
+ return -EFAULT;
+
+ return len;
+}
+
+/**
+ * vtpm_fops_write - Write TPM responses on 'server side'
+ *
+ * Return value:
+ * Number of bytes read or negative error value
+ */
+static ssize_t vtpm_fops_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t *off)
+{
+ struct vtpm_dev *vtpm_dev = filp->private_data;
+
+ mutex_lock(&vtpm_dev->buf_lock);
+
+ if (count > sizeof(vtpm_dev->buffer) ||
+ !(vtpm_dev->state & STATE_WAIT_RESPONSE_FLAG)) {
+ mutex_unlock(&vtpm_dev->buf_lock);
+ return -EIO;
+ }
+
+ vtpm_dev->state &= ~STATE_WAIT_RESPONSE_FLAG;
+
+ vtpm_dev->req_len = 0;
+
+ if (copy_from_user(vtpm_dev->buffer, buf, count)) {
+ mutex_unlock(&vtpm_dev->buf_lock);
+ return -EFAULT;
+ }
+
+ vtpm_dev->resp_len = count;
+
+ mutex_unlock(&vtpm_dev->buf_lock);
+
+ wake_up_interruptible(&vtpm_dev->wq);
+
+ return count;
+}
+
+/*
+ * vtpm_fops_poll: Poll status on 'server side'
+ *
+ * Return value:
+ * Poll flags
+ */
+static unsigned int vtpm_fops_poll(struct file *filp, poll_table *wait)
+{
+ struct vtpm_dev *vtpm_dev = filp->private_data;
+ unsigned ret;
+
+ poll_wait(filp, &vtpm_dev->wq, wait);
+
+ ret = POLLOUT;
+
+ mutex_lock(&vtpm_dev->buf_lock);
+
+ if (vtpm_dev->req_len)
+ ret |= POLLIN | POLLRDNORM;
+
+ mutex_unlock(&vtpm_dev->buf_lock);
+
+ return ret;
+}
+
+/*
+ * vtpm_fops_open - Open vTPM device on 'server side'
+ *
+ * Called when setting up the anonymous file descriptor
+ */
+static void vtpm_fops_open(struct file *filp)
+{
+ struct vtpm_dev *vtpm_dev = filp->private_data;
+
+ vtpm_dev->state |= STATE_OPENED_FLAG;
+}
+
+/**
+ * vtpm_fops_undo_open - counter-part to vtpm_fops_open
+ *
+ * Call to undo vtpm_fops_open
+ */
+static void vtpm_fops_undo_open(struct vtpm_dev *vtpm_dev)
+{
+ mutex_lock(&vtpm_dev->buf_lock);
+
+ vtpm_dev->state &= ~STATE_OPENED_FLAG;
+
+ mutex_unlock(&vtpm_dev->buf_lock);
+
+ /* no more TPM responses -- wake up anyone waiting for them */
+ wake_up_interruptible(&vtpm_dev->wq);
+}
+
+/*
+ * vtpm_fops_release: Close 'server side'
+ *
+ * Return value:
+ * Always returns 0.
+ */
+static int vtpm_fops_release(struct inode *inode, struct file *filp)
+{
+ struct vtpm_dev *vtpm_dev = filp->private_data;
+
+ filp->private_data = NULL;
+
+ vtpm_delete_device(vtpm_dev);
+
+ return 0;
+}
+
+static const struct file_operations vtpm_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .read = vtpm_fops_read,
+ .write = vtpm_fops_write,
+ .poll = vtpm_fops_poll,
+ .release = vtpm_fops_release,
+};
+
+/*
+ * Functions invoked by the core TPM driver to send TPM commands to
+ * 'server side' and receive responses from there.
+ */
+
+/*
+ * Called when core TPM driver reads TPM responses from 'server side'
+ *
+ * Return value:
+ * Number of TPM response bytes read, negative error value otherwise
+ */
+static int vtpm_tpm_op_recv(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+ struct vtpm_dev *vtpm_dev = chip->vendor.priv;
+ size_t len;
+
+ if (!vtpm_dev)
+ return -EIO;
+
+ /* process gone ? */
+ mutex_lock(&vtpm_dev->buf_lock);
+
+ if (!(vtpm_dev->state & STATE_OPENED_FLAG)) {
+ mutex_unlock(&vtpm_dev->buf_lock);
+ return -EPIPE;
+ }
+
+ len = vtpm_dev->resp_len;
+ if (count < len) {
+ dev_err(&chip->dev,
+ "Invalid size in recv: count=%zd, resp_len=%zd\n",
+ count, len);
+ len = -EIO;
+ goto out;
+ }
+
+ memcpy(buf, vtpm_dev->buffer, len);
+ vtpm_dev->resp_len = 0;
+
+out:
+ mutex_unlock(&vtpm_dev->buf_lock);
+
+ return len;
+}
+
+/*
+ * Called when core TPM driver forwards TPM requests to 'server side'.
+ *
+ * Return value:
+ * 0 in case of success, negative error value otherwise.
+ */
+static int vtpm_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+ struct vtpm_dev *vtpm_dev = chip->vendor.priv;
+ int rc = 0;
+
+ if (!vtpm_dev)
+ return -EIO;
+
+ if (count > sizeof(vtpm_dev->buffer)) {
+ dev_err(&chip->dev,
+ "Invalid size in send: count=%zd, buffer size=%zd\n",
+ count, sizeof(vtpm_dev->buffer));
+ return -EIO;
+ }
+
+ mutex_lock(&vtpm_dev->buf_lock);
+
+ if (!(vtpm_dev->state & STATE_OPENED_FLAG)) {
+ mutex_unlock(&vtpm_dev->buf_lock);
+ return -EPIPE;
+ }
+
+ vtpm_dev->resp_len = 0;
+
+ vtpm_dev->req_len = count;
+ memcpy(vtpm_dev->buffer, buf, count);
+
+ vtpm_dev->state &= ~STATE_WAIT_RESPONSE_FLAG;
+
+ mutex_unlock(&vtpm_dev->buf_lock);
+
+ wake_up_interruptible(&vtpm_dev->wq);
+
+ return rc;
+}
+
+static void vtpm_tpm_op_cancel(struct tpm_chip *chip)
+{
+ /* not supported */
+}
+
+static u8 vtpm_tpm_op_status(struct tpm_chip *chip)
+{
+ struct vtpm_dev *vtpm_dev = chip->vendor.priv;
+
+ if (vtpm_dev->resp_len)
+ return VTPM_REQ_COMPLETE_FLAG;
+
+ return 0;
+}
+
+static bool vtpm_tpm_req_canceled(struct tpm_chip *chip, u8 status)
+{
+ struct vtpm_dev *vtpm_dev = chip->vendor.priv;
+ bool ret;
+
+ mutex_lock(&vtpm_dev->buf_lock);
+
+ ret = !(vtpm_dev->state & STATE_OPENED_FLAG);
+
+ mutex_unlock(&vtpm_dev->buf_lock);
+
+ return ret;
+}
+
+static const struct tpm_class_ops vtpm_tpm_ops = {
+ .recv = vtpm_tpm_op_recv,
+ .send = vtpm_tpm_op_send,
+ .cancel = vtpm_tpm_op_cancel,
+ .status = vtpm_tpm_op_status,
+ .req_complete_mask = VTPM_REQ_COMPLETE_FLAG,
+ .req_complete_val = VTPM_REQ_COMPLETE_FLAG,
+ .req_canceled = vtpm_tpm_req_canceled,
+};
+
+/*
+ * Code related to creation and deletion of device pairs
+ */
+static struct vtpm_dev *vtpm_create_vtpm_dev(void)
+{
+ struct vtpm_dev *vtpm_dev;
+ struct tpm_chip *chip;
+ int err;
+
+ vtpm_dev = kzalloc(sizeof(*vtpm_dev), GFP_KERNEL);
+ if (vtpm_dev == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ init_waitqueue_head(&vtpm_dev->wq);
+ mutex_init(&vtpm_dev->buf_lock);
+
+ chip = tpm_chip_alloc(NULL, &vtpm_tpm_ops);
+ if (IS_ERR(chip)) {
+ err = PTR_ERR(chip);
+ goto err_vtpm_dev_free;
+ }
+ chip->vendor.priv = vtpm_dev;
+
+ vtpm_dev->chip = chip;
+
+ return vtpm_dev;
+
+err_vtpm_dev_free:
+ kfree(vtpm_dev);
+
+ return ERR_PTR(err);
+}
+
+/*
+ * Undo what has been done in vtpm_create_vtpm_dev
+ */
+static inline void vtpm_delete_vtpm_dev(struct vtpm_dev *vtpm_dev)
+{
+ put_device(&vtpm_dev->chip->dev); /* frees chip */
+ kfree(vtpm_dev);
+}
+
+/*
+ * Create a /dev/tpm%d and 'server side' file descriptor pair
+ *
+ * Return value:
+ * Returns file pointer on success, an error value otherwise
+ */
+static struct file *vtpm_create_device(
+ struct vtpm_new_dev *vtpm_new_dev)
+{
+ struct vtpm_dev *vtpm_dev;
+ int rc, fd;
+ struct file *file;
+
+ if (vtpm_new_dev->flags & ~VTPM_FLAGS_ALL)
+ return ERR_PTR(-ENOSYS);
+
+ vtpm_dev = vtpm_create_vtpm_dev();
+ if (IS_ERR(vtpm_dev))
+ return ERR_CAST(vtpm_dev);
+
+ vtpm_dev->flags = vtpm_new_dev->flags;
+
+ /* setup an anonymous file for the server-side */
+ fd = get_unused_fd_flags(O_RDWR);
+ if (fd < 0) {
+ rc = fd;
+ goto err_delete_vtpm_dev;
+ }
+
+ file = anon_inode_getfile("[vtpms]", &vtpm_fops, vtpm_dev, O_RDWR);
+ if (IS_ERR(file)) {
+ rc = PTR_ERR(file);
+ goto err_put_unused_fd;
+ }
+
+ /* from now on we can unwind with put_unused_fd() + fput() */
+ /* simulate an open() on the server side */
+ vtpm_fops_open(file);
+
+ if (vtpm_dev->flags & VTPM_FLAG_TPM2)
+ vtpm_dev->chip->flags |= TPM_CHIP_FLAG_TPM2;
+
+ rc = tpm_chip_register(vtpm_dev->chip);
+ if (rc)
+ goto err_vtpm_fput;
+
+ vtpm_new_dev->fd = fd;
+ vtpm_new_dev->major = MAJOR(vtpm_dev->chip->dev.devt);
+ vtpm_new_dev->minor = MINOR(vtpm_dev->chip->dev.devt);
+ vtpm_new_dev->dev_num = vtpm_dev->chip->dev_num;
+
+ return file;
+
+err_vtpm_fput:
+ put_unused_fd(fd);
+ fput(file);
+
+ return ERR_PTR(rc);
+
+err_put_unused_fd:
+ put_unused_fd(fd);
+
+err_delete_vtpm_dev:
+ vtpm_delete_vtpm_dev(vtpm_dev);
+
+ return ERR_PTR(rc);
+}
+
+/*
+ * Counter part to vtpm_create_device.
+ */
+static void vtpm_delete_device(struct vtpm_dev *vtpm_dev)
+{
+ tpm_chip_unregister(vtpm_dev->chip);
+
+ vtpm_fops_undo_open(vtpm_dev);
+
+ vtpm_delete_vtpm_dev(vtpm_dev);
+}
+
+/*
+ * Code related to the control device /dev/vtpmx
+ */
+
+/*
+ * vtpmx_fops_ioctl: ioctl on /dev/vtpmx
+ *
+ * Return value:
+ * Returns 0 on success, a negative error code otherwise.
+ */
+static long vtpmx_fops_ioctl(struct file *f, unsigned int ioctl,
+ unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ struct vtpm_new_dev *vtpm_new_dev_p;
+ struct vtpm_new_dev vtpm_new_dev;
+ struct file *file;
+
+ switch (ioctl) {
+ case VTPM_NEW_DEV:
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ vtpm_new_dev_p = argp;
+ if (copy_from_user(&vtpm_new_dev, vtpm_new_dev_p,
+ sizeof(vtpm_new_dev)))
+ return -EFAULT;
+ file = vtpm_create_device(&vtpm_new_dev);
+ if (IS_ERR(file))
+ return PTR_ERR(file);
+ if (copy_to_user(vtpm_new_dev_p, &vtpm_new_dev,
+ sizeof(vtpm_new_dev))) {
+ put_unused_fd(vtpm_new_dev.fd);
+ fput(file);
+ return -EFAULT;
+ }
+
+ fd_install(vtpm_new_dev.fd, file);
+ return 0;
+
+ default:
+ return -ENOSYS;
+ }
+}
+
+#ifdef CONFIG_COMPAT
+static long vtpmx_fops_compat_ioctl(struct file *f, unsigned int ioctl,
+ unsigned long arg)
+{
+ return vtpmx_fops_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
+}
+#endif
+
+static const struct file_operations vtpmx_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = vtpmx_fops_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = vtpmx_fops_compat_ioctl,
+#endif
+ .llseek = noop_llseek,
+};
+
+static struct miscdevice vtpmx_miscdev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "vtpmx",
+ .fops = &vtpmx_fops,
+};
+
+static int vtpmx_init(void)
+{
+ return misc_register(&vtpmx_miscdev);
+}
+
+static void vtpmx_cleanup(void)
+{
+ misc_deregister(&vtpmx_miscdev);
+}
+
+static int __init vtpm_module_init(void)
+{
+ int rc;
+
+ rc = vtpmx_init();
+ if (rc) {
+ pr_err("couldn't create vtpmx device\n");
+ return rc;
+ }
+
+ return 0;
+}
+
+static void __exit vtpm_module_exit(void)
+{
+ vtpmx_cleanup();
+}
+
+module_init(vtpm_module_init);
+module_exit(vtpm_module_exit);
+
+MODULE_AUTHOR("Stefan Berger (stefanb@us.ibm.com)");
+MODULE_DESCRIPTION("vTPM Driver");
+MODULE_VERSION("0.1");
+MODULE_LICENSE("GPL");
diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild
index ebd10e6..3a602c9 100644
--- a/include/uapi/linux/Kbuild
+++ b/include/uapi/linux/Kbuild
@@ -449,6 +449,7 @@ header-y += virtio_scsi.h
header-y += virtio_types.h
header-y += vm_sockets.h
header-y += vt.h
+header-y += vtpm.h
header-y += wait.h
header-y += wanrouter.h
header-y += watchdog.h
diff --git a/include/uapi/linux/vtpm.h b/include/uapi/linux/vtpm.h
new file mode 100644
index 0000000..4adc486
--- /dev/null
+++ b/include/uapi/linux/vtpm.h
@@ -0,0 +1,41 @@
+/*
+ * Definitions for the VTPM interface
+ * Copyright (c) 2015, 2016, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef _UAPI_LINUX_VTPM_H
+#define _UAPI_LINUX_VTPM_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+/* ioctls */
+
+struct vtpm_new_dev {
+ __u32 flags; /* input */
+ __u32 dev_num; /* output */
+ __u32 fd; /* output */
+ __u32 major; /* output */
+ __u32 minor; /* output */
+};
+
+/* above flags */
+#define VTPM_FLAG_TPM2 1 /* emulator is TPM 2 */
+
+/* all supported flags */
+#define VTPM_FLAGS_ALL (VTPM_FLAG_TPM2)
+
+#define VTPM_TPM 0xa0
+
+#define VTPM_NEW_DEV _IOW(VTPM_TPM, 0x00, struct vtpm_new_dev)
+
+#endif /* _UAPI_LINUX_VTPM_H */
--
2.4.3
^ permalink raw reply [flat|nested] 3+ messages in thread* [PATCH v5 09/11] tpm: Initialize TPM and get durations and timeouts
[not found] <1457353514-2509-1-git-send-email-stefanb@linux.vnet.ibm.com>
2016-03-07 12:25 ` [PATCH v5 08/11] tpm: Driver for supporting multiple emulated TPMs Stefan Berger
@ 2016-03-07 12:25 ` Stefan Berger
2016-03-07 12:25 ` [PATCH v5 10/11] tpm: Add documentation for the tpm_vtpm device driver Stefan Berger
2 siblings, 0 replies; 3+ messages in thread
From: Stefan Berger @ 2016-03-07 12:25 UTC (permalink / raw)
To: tpmdd-devel
Cc: jarkko.sakkinen, jgunthorpe, Stefan Berger, linux-kernel,
linux-doc, linux-api
Add the retrieval of TPM 1.2 durations and timeouts. Since this requires
the startup of the TPM, do this for TPM 1.2 and TPM 2.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
CC: linux-kernel@vger.kernel.org
CC: linux-doc@vger.kernel.org
CC: linux-api@vger.kernel.org
---
drivers/char/tpm/tpm_vtpm.c | 94 ++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 85 insertions(+), 9 deletions(-)
diff --git a/drivers/char/tpm/tpm_vtpm.c b/drivers/char/tpm/tpm_vtpm.c
index 245ce91..b048898 100644
--- a/drivers/char/tpm/tpm_vtpm.c
+++ b/drivers/char/tpm/tpm_vtpm.c
@@ -45,8 +45,11 @@ struct vtpm_dev {
size_t req_len; /* length of queued TPM request */
size_t resp_len; /* length of queued TPM response */
u8 buffer[TPM_BUFSIZE]; /* request/response buffer */
+
+ struct work_struct work; /* task that retrieves TPM timeouts */
};
+static struct workqueue_struct *workqueue;
static void vtpm_delete_device(struct vtpm_dev *vtpm_dev);
@@ -67,6 +70,15 @@ static ssize_t vtpm_fops_read(struct file *filp, char __user *buf,
size_t len;
int sig, rc;
+ mutex_lock(&vtpm_dev->buf_lock);
+
+ if (!(vtpm_dev->state & STATE_OPENED_FLAG)) {
+ mutex_unlock(&vtpm_dev->buf_lock);
+ return -EPIPE;
+ }
+
+ mutex_unlock(&vtpm_dev->buf_lock);
+
sig = wait_event_interruptible(vtpm_dev->wq, vtpm_dev->req_len != 0);
if (sig)
return -EINTR;
@@ -110,6 +122,11 @@ static ssize_t vtpm_fops_write(struct file *filp, const char __user *buf,
mutex_lock(&vtpm_dev->buf_lock);
+ if (!(vtpm_dev->state & STATE_OPENED_FLAG)) {
+ mutex_unlock(&vtpm_dev->buf_lock);
+ return -EPIPE;
+ }
+
if (count > sizeof(vtpm_dev->buffer) ||
!(vtpm_dev->state & STATE_WAIT_RESPONSE_FLAG)) {
mutex_unlock(&vtpm_dev->buf_lock);
@@ -154,6 +171,9 @@ static unsigned int vtpm_fops_poll(struct file *filp, poll_table *wait)
if (vtpm_dev->req_len)
ret |= POLLIN | POLLRDNORM;
+ if (!(vtpm_dev->state & STATE_OPENED_FLAG))
+ ret |= POLLHUP;
+
mutex_unlock(&vtpm_dev->buf_lock);
return ret;
@@ -341,6 +361,54 @@ static const struct tpm_class_ops vtpm_tpm_ops = {
};
/*
+ * Code related to the startup of the TPM 2 and startup of TPM 1.2 +
+ * retrieval of timeouts and durations.
+ */
+
+static void vtpm_dev_work(struct work_struct *work)
+{
+ struct vtpm_dev *vtpm_dev = container_of(work, struct vtpm_dev, work);
+ int rc;
+
+ if (vtpm_dev->flags & VTPM_FLAG_TPM2)
+ rc = tpm2_startup(vtpm_dev->chip, TPM2_SU_CLEAR);
+ else
+ rc = tpm_get_timeouts(vtpm_dev->chip);
+
+ if (rc)
+ goto err;
+
+ rc = tpm_chip_register(vtpm_dev->chip);
+ if (rc)
+ goto err;
+
+ return;
+
+err:
+ vtpm_fops_undo_open(vtpm_dev);
+}
+
+/*
+ * vtpm_dev_work_stop: make sure the work has finished
+ *
+ * This function is useful when user space closed the fd
+ * while the driver still determines timeouts.
+ */
+static void vtpm_dev_work_stop(struct vtpm_dev *vtpm_dev)
+{
+ vtpm_fops_undo_open(vtpm_dev);
+ flush_work(&vtpm_dev->work);
+}
+
+/*
+ * vtpm_dev_work_start: Schedule the work for TPM 1.2 & 2 initialization
+ */
+static inline void vtpm_dev_work_start(struct vtpm_dev *vtpm_dev)
+{
+ queue_work(workqueue, &vtpm_dev->work);
+}
+
+/*
* Code related to creation and deletion of device pairs
*/
static struct vtpm_dev *vtpm_create_vtpm_dev(void)
@@ -355,6 +423,7 @@ static struct vtpm_dev *vtpm_create_vtpm_dev(void)
init_waitqueue_head(&vtpm_dev->wq);
mutex_init(&vtpm_dev->buf_lock);
+ INIT_WORK(&vtpm_dev->work, vtpm_dev_work);
chip = tpm_chip_alloc(NULL, &vtpm_tpm_ops);
if (IS_ERR(chip)) {
@@ -424,9 +493,7 @@ static struct file *vtpm_create_device(
if (vtpm_dev->flags & VTPM_FLAG_TPM2)
vtpm_dev->chip->flags |= TPM_CHIP_FLAG_TPM2;
- rc = tpm_chip_register(vtpm_dev->chip);
- if (rc)
- goto err_vtpm_fput;
+ vtpm_dev_work_start(vtpm_dev);
vtpm_new_dev->fd = fd;
vtpm_new_dev->major = MAJOR(vtpm_dev->chip->dev.devt);
@@ -435,12 +502,6 @@ static struct file *vtpm_create_device(
return file;
-err_vtpm_fput:
- put_unused_fd(fd);
- fput(file);
-
- return ERR_PTR(rc);
-
err_put_unused_fd:
put_unused_fd(fd);
@@ -455,6 +516,8 @@ err_delete_vtpm_dev:
*/
static void vtpm_delete_device(struct vtpm_dev *vtpm_dev)
{
+ vtpm_dev_work_stop(vtpm_dev);
+
tpm_chip_unregister(vtpm_dev->chip);
vtpm_fops_undo_open(vtpm_dev);
@@ -549,11 +612,24 @@ static int __init vtpm_module_init(void)
return rc;
}
+ workqueue = create_workqueue("tpm-vtpm");
+ if (!workqueue) {
+ pr_err("couldn't create workqueue\n");
+ rc = -ENOMEM;
+ goto err_vtpmx_cleanup;
+ }
+
return 0;
+
+err_vtpmx_cleanup:
+ vtpmx_cleanup();
+
+ return rc;
}
static void __exit vtpm_module_exit(void)
{
+ destroy_workqueue(workqueue);
vtpmx_cleanup();
}
--
2.4.3
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