Re: [PATCH v3 1/7] fpga: sec-mgr: intel fpga security manager class driver

[Russ Weight]

On 10/7/20 10:06 AM, Moritz Fischer wrote:
> On Wed, Oct 07, 2020 at 09:43:24AM -0700, Russ Weight wrote:
>>
>> On 10/7/20 7:44 AM, Moritz Fischer wrote:
>>> Hi Russ,
>>>
>>> On Tue, Oct 06, 2020 at 05:09:58PM -0700, Russ Weight wrote:
>>>> Create the Intel Security Manager class driver. The security
>>>> manager provides interfaces to manage secure updates for the
>>>> FPGA and BMC images that are stored in FLASH. The driver can
>>>> also be used to update root entry hashes and to cancel code
>>>> signing keys.
>>>>
>>>> This patch creates the class driver and provides sysfs
>>>> interfaces for displaying root entry hashes, canceled code
>>>> signing keys and flash counts.
>>>>
>>>> Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
>>>> Reviewed-by: Tom Rix <trix@xxxxxxxxxx>
>>>> ---
>>>> v3:
>>>>   - Modified sysfs handler check in check_sysfs_handler() to make
>>>>     it more readable.
>>>> ---
>>>> v2:
>>>>   - Bumped documentation dates and versions
>>>>   - Added Documentation/fpga/ifpga-sec-mgr.rst 
>>>>   - Removed references to bmc_flash_count & smbus_flash_count (not supported)
>>>>   - Split ifpga_sec_mgr_register() into create() and register() functions
>>>>   - Added devm_ifpga_sec_mgr_create()
>>>>   - Removed typedefs for imgr ops
>>>> ---
>>>>  .../ABI/testing/sysfs-class-ifpga-sec-mgr     |  67 +++
>>>>  Documentation/fpga/ifpga-sec-mgr.rst          |  50 ++
>>>>  Documentation/fpga/index.rst                  |   1 +
>>>>  MAINTAINERS                                   |   9 +
>>>>  drivers/fpga/Kconfig                          |   9 +
>>>>  drivers/fpga/Makefile                         |   3 +
>>>>  drivers/fpga/ifpga-sec-mgr.c                  | 430 ++++++++++++++++++
>>>>  include/linux/fpga/ifpga-sec-mgr.h            |  81 ++++
>>>>  8 files changed, 650 insertions(+)
>>>>  create mode 100644 Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr
>>>>  create mode 100644 Documentation/fpga/ifpga-sec-mgr.rst
>>>>  create mode 100644 drivers/fpga/ifpga-sec-mgr.c
>>>>  create mode 100644 include/linux/fpga/ifpga-sec-mgr.h
>>>>
>>>> diff --git a/Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr b/Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr
>>>> new file mode 100644
>>>> index 000000000000..707958971bcb
>>>> --- /dev/null
>>>> +++ b/Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr
>>>> @@ -0,0 +1,67 @@
>>>> +What: 		/sys/class/ifpga_sec_mgr/ifpga_secX/name
>>>> +Date:		Oct 2020
>>>> +KernelVersion:  5.11
>>>> +Contact:	Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> +Description:	Name of low level fpga security manager driver.
>>>> +
>>>> +What: 		/sys/class/ifpga_sec_mgr/ifpga_secX/security/sr_root_entry_hash
>>>> +Date:		Oct 2020
>>>> +KernelVersion:  5.11
>>>> +Contact:	Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> +Description:	Read only. Returns the root entry hash for the static
>>>> +		region if one is programmed, else it returns the
>>>> +		string: "hash not programmed".  This file is only
>>>> +		visible if the underlying device supports it.
>>>> +		Format: "0x%x".
>>>> +
>>>> +What: 		/sys/class/ifpga_sec_mgr/ifpga_secX/security/pr_root_entry_hash
>>>> +Date:		Oct 2020
>>>> +KernelVersion:  5.11
>>>> +Contact:	Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> +Description:	Read only. Returns the root entry hash for the partial
>>>> +		reconfiguration region if one is programmed, else it
>>>> +		returns the string: "hash not programmed".  This file
>>>> +		is only visible if the underlying device supports it.
>>>> +		Format: "0x%x".
>>>> +
>>>> +What: 		/sys/class/ifpga_sec_mgr/ifpga_secX/security/bmc_root_entry_hash
>>>> +Date:		Oct 2020
>>>> +KernelVersion:  5.11
>>>> +Contact:	Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> +Description:	Read only. Returns the root entry hash for the BMC image
>>>> +		if one is programmed, else it returns the string:
>>>> +		"hash not programmed".  This file is only visible if the
>>>> +		underlying device supports it.
>>>> +		Format: "0x%x".
>>>> +
>>>> +What: 		/sys/class/ifpga_sec_mgr/ifpga_secX/security/sr_canceled_csks
>>>> +Date:		Oct 2020
>>>> +KernelVersion:  5.11
>>>> +Contact:	Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> +Description:	Read only. Returns a list of indices for canceled code
>>>> +		signing keys for the static region. The standard bitmap
>>>> +		list format is used (e.g. "1,2-6,9").
>>>> +
>>>> +What: 		/sys/class/ifpga_sec_mgr/ifpga_secX/security/pr_canceled_csks
>>>> +Date:		Oct 2020
>>>> +KernelVersion:  5.11
>>>> +Contact:	Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> +Description:	Read only. Returns a list of indices for canceled code
>>>> +		signing keys for the partial reconfiguration region. The
>>>> +		standard bitmap list format is used (e.g. "1,2-6,9").
>>>> +
>>>> +What: 		/sys/class/ifpga_sec_mgr/ifpga_secX/security/bmc_canceled_csks
>>>> +Date:		Oct 2020
>>>> +KernelVersion:  5.11
>>>> +Contact:	Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> +Description:	Read only. Returns a list of indices for canceled code
>>>> +		signing keys for the BMC.  The standard bitmap list format
>>>> +		is used (e.g. "1,2-6,9").
>>>> +
>>>> +What: 		/sys/class/ifpga_sec_mgr/ifpga_secX/security/user_flash_count
>>>> +Date:		Oct 2020
>>>> +KernelVersion:  5.11
>>>> +Contact:	Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> +Description:	Read only. Returns number of times the user image for the
>>>> +		static region has been flashed.
>>>> +		Format: "%u".
>>>> diff --git a/Documentation/fpga/ifpga-sec-mgr.rst b/Documentation/fpga/ifpga-sec-mgr.rst
>>>> new file mode 100644
>>>> index 000000000000..02f3f65b182b
>>>> --- /dev/null
>>>> +++ b/Documentation/fpga/ifpga-sec-mgr.rst
>>>> @@ -0,0 +1,50 @@
>>>> +.. SPDX-License-Identifier: GPL-2.0
>>>> +
>>>> +========================================
>>>> +Intel FPGA Security Manager Class Driver
>>>> +========================================
> Can we make this "FPGA Security Manager Class Driver" then, and
> generally 's/ifpga/fpga' for the framework part?
>
> I'm cool with keeping the intel part on the intel specific stuff.
Yes - I'll make the change.

Thanks,
- Russ
>>>> +
>>>> +The Intel FPGA Security Manager class driver provides a common
>>>> +API for user-space tools to manage updates for secure Intel FPGA
>>>> +devices. Device drivers that instantiate the Intel Security
>>>> +Manager class driver will interact with a HW secure update
>>>> +engine in order to transfer new FPGA and BMC images to FLASH so
>>>> +that they will be automatically loaded when the FPGA card reboots.
>>> I have a general question here, sorry I didn't bring this up earlier,
>>> but do you see a way of making this a more generic interface that could be
>>> used by other vendors, with the Intel implementation being one
>>> implementation of it?
>>>
>>> Having a BMC setup to securely update the FPGA images in a flash seems
>>> to be generic enough that it could be common.
>>>
>>> I guess what I'm trying to avoid is having the Xilinx FPGA secure update
>>> manager in 3 months, that has it's own set of API calls.
>> I believe it is already generic enough that it could be used by other vendors.
>> It supports a preparation phase (erase the flash, any other setup required),
>> A writing phase (transfer data from a source file to the device), a programming
>> phase (waiting for the hardware to perform the udpate), and an optional cleanup
>> phase (any clean up that needs be done unconditionally, whether or succeeds or
>> fails).
>>
>> - Russ
>>>> +
>>>> +A significant difference between the FPGA Manager and the Intel FPGA
>>>> +Security Manager is that the FPGA Manager does a live update (Partial
>>>> +Reconfiguration) to a device, whereas the Intel FPGA Security Manager
>>>> +updates the FLASH images for the Static Region and the BMC so that
>>>> +they will be loaded the next time the FPGA card boots. Security is
>>>> +enforced by hardware and firmware. The security manager interacts
>>>> +with the firmware to initiate an update, pass in the necessary data,
>>>> +and collect status on the update.
>>>> +
>>>> +In addition to managing secure updates of the FPGA and BMC images,
>>>> +the Intel FPGA Security Manager update process may also used to
>>>> +program root entry hashes and cancellation keys for the FPGA static
>>>> +region, the FPGA partial reconfiguration region, and the BMC.
>>>> +
>>>> +Secure updates make use of the request_firmware framework, which
>>>> +requires that image files are accessible under /lib/firmware. A request
>>>> +for a secure update returns immediately, while the update itself
>>>> +proceeds in the context of a kernel worker thread. Sysfs files provide
>>>> +a means for monitoring the progress of a secure update and for
>>>> +retrieving error information in the event of a failure.
>>>> +
>>>> +Sysfs Attributes
>>>> +================
>>>> +
>>>> +The API consists of two groups of sysfs attributes as described below.
>>>> +
>>>> +1. Files in the *security* sub-directory can be used to read security
>>>> +   information including: Root Entry Hashes (REH), Cancelled Code
>>>> +   Signing Keys (CSK), and the flash update count for FPGA images.
>>>> +
>>>> +2. Files in the *update* sub-directory can be used to instantiate and
>>>> +   monitor a secure update.
>>>> +
>>>> +
>>>> +See `<../ABI/testing/sysfs-class-ifpga-sec-mgr>`__ for a full
>>>> +description of the sysfs attributes for the Intel FPGA Security
>>>> +Manager.
>>>> diff --git a/Documentation/fpga/index.rst b/Documentation/fpga/index.rst
>>>> index f80f95667ca2..ba9c6b1917bd 100644
>>>> --- a/Documentation/fpga/index.rst
>>>> +++ b/Documentation/fpga/index.rst
>>>> @@ -8,6 +8,7 @@ fpga
>>>>      :maxdepth: 1
>>>>  
>>>>      dfl
>>>> +    ifpga-sec-mgr
>>>>  
>>>>  .. only::  subproject and html
>>>>  
>>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>>> index 03de3a2aaa7e..e7f83d3c46d3 100644
>>>> --- a/MAINTAINERS
>>>> +++ b/MAINTAINERS
>>>> @@ -6899,6 +6899,15 @@ F:	Documentation/fpga/
>>>>  F:	drivers/fpga/
>>>>  F:	include/linux/fpga/
>>>>  
>>>> +INTEL FPGA SECURITY MANAGER DRIVERS
>>>> +M:	Russ Weight <russell.h.weight@xxxxxxxxx>
>>>> +L:	linux-fpga@xxxxxxxxxxxxxxx
>>>> +S:	Maintained
>>>> +F:	Documentation/ABI/testing/sysfs-class-ifpga-sec-mgr
>>>> +F:	Documentation/fpga/ifpga-sec-mgr.rst
>>>> +F:	drivers/fpga/ifpga-sec-mgr.c
>>>> +F:	include/linux/fpga/ifpga-sec-mgr.h
>>>> +
>>>>  FPU EMULATOR
>>>>  M:	Bill Metzenthen <billm@xxxxxxxxxxxxx>
>>>>  S:	Maintained
>>>> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
>>>> index 7cd5a29fc437..bf566a625be7 100644
>>>> --- a/drivers/fpga/Kconfig
>>>> +++ b/drivers/fpga/Kconfig
>>>> @@ -215,4 +215,13 @@ config FPGA_MGR_ZYNQMP_FPGA
>>>>  	  to configure the programmable logic(PL) through PS
>>>>  	  on ZynqMP SoC.
>>>>  
>>>> +config IFPGA_SEC_MGR
>>>> +	tristate "Intel Security Manager for FPGA"
>>>> +	help
>>>> +	  The Intel Security Manager class driver presents a common
>>>> +	  user API for managing secure updates for Intel FPGA
>>>> +	  devices, including flash images for the FPGA static
>>>> +	  region and for the BMC. Select this option to enable
>>>> +	  updates for secure FPGA devices.
>>>> +
>>>>  endif # FPGA
>>>> diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
>>>> index d8e21dfc6778..2e1d29c3d915 100644
>>>> --- a/drivers/fpga/Makefile
>>>> +++ b/drivers/fpga/Makefile
>>>> @@ -21,6 +21,9 @@ obj-$(CONFIG_FPGA_MGR_ZYNQMP_FPGA)	+= zynqmp-fpga.o
>>>>  obj-$(CONFIG_ALTERA_PR_IP_CORE)         += altera-pr-ip-core.o
>>>>  obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT)    += altera-pr-ip-core-plat.o
>>>>  
>>>> +# Intel FPGA Security Manager Framework
>>>> +obj-$(CONFIG_IFPGA_SEC_MGR)		+= ifpga-sec-mgr.o
>>>> +
>>>>  # FPGA Bridge Drivers
>>>>  obj-$(CONFIG_FPGA_BRIDGE)		+= fpga-bridge.o
>>>>  obj-$(CONFIG_SOCFPGA_FPGA_BRIDGE)	+= altera-hps2fpga.o altera-fpga2sdram.o
>>>> diff --git a/drivers/fpga/ifpga-sec-mgr.c b/drivers/fpga/ifpga-sec-mgr.c
>>>> new file mode 100644
>>>> index 000000000000..26609fb9b73d
>>>> --- /dev/null
>>>> +++ b/drivers/fpga/ifpga-sec-mgr.c
>>>> @@ -0,0 +1,430 @@
>>>> +// SPDX-License-Identifier: GPL-2.0
>>>> +/*
>>>> + * Intel Security Manager for FPGA
>>>> + *
>>>> + * Copyright (C) 2019-2020 Intel Corporation, Inc.
>>>> + */
>>>> +
>>>> +#include <linux/fpga/ifpga-sec-mgr.h>
>>>> +#include <linux/idr.h>
>>>> +#include <linux/module.h>
>>>> +#include <linux/slab.h>
>>>> +#include <linux/vmalloc.h>
>>>> +
>>>> +static DEFINE_IDA(ifpga_sec_mgr_ida);
>>>> +static struct class *ifpga_sec_mgr_class;
>>>> +
>>>> +#define to_sec_mgr(d) container_of(d, struct ifpga_sec_mgr, dev)
>>>> +
>>>> +static ssize_t
>>>> +show_canceled_csk(struct ifpga_sec_mgr *imgr,
>>>> +		  int (*get_csk)(struct ifpga_sec_mgr *imgr,
>>>> +				 unsigned long *csk_map, unsigned int nbits),
>>>> +		  int (*get_csk_nbits)(struct ifpga_sec_mgr *imgr),
>>>> +		  char *buf)
>>>> +{
>>>> +	unsigned long *csk_map = NULL;
>>>> +	unsigned int nbits;
>>>> +	int ret;
>>>> +
>>>> +	ret = get_csk_nbits(imgr);
>>>> +	if (ret < 0)
>>>> +		return ret;
>>>> +
>>>> +	nbits = (unsigned int)ret;
>>>> +	csk_map = vmalloc(sizeof(unsigned long) * BITS_TO_LONGS(nbits));
>>>> +	if (!csk_map)
>>>> +		return -ENOMEM;
>>>> +
>>>> +	ret = get_csk(imgr, csk_map, nbits);
>>>> +	if (ret)
>>>> +		goto vfree_exit;
>>>> +
>>>> +	ret = bitmap_print_to_pagebuf(1, buf, csk_map, nbits);
>>>> +
>>>> +vfree_exit:
>>>> +	vfree(csk_map);
>>>> +	return ret;
>>>> +}
>>>> +
>>>> +static ssize_t
>>>> +show_root_entry_hash(struct ifpga_sec_mgr *imgr,
>>>> +		     int (*get_reh)(struct ifpga_sec_mgr *imgr, u8 *hash,
>>>> +				    unsigned int size),
>>>> +		     int (*get_reh_size)(struct ifpga_sec_mgr *imgr),
>>>> +		     char *buf)
>>>> +{
>>>> +	int size, i, cnt, ret;
>>>> +	u8 *hash;
>>>> +
>>>> +	ret = get_reh_size(imgr);
>>>> +	if (ret < 0)
>>>> +		return ret;
>>>> +	else if (!ret)
>>>> +		return sprintf(buf, "hash not programmed\n");
>>>> +
>>>> +	size = ret;
>>>> +	hash = vmalloc(size);
>>>> +	if (!hash)
>>>> +		return -ENOMEM;
>>>> +
>>>> +	ret = get_reh(imgr, hash, size);
>>>> +	if (ret)
>>>> +		goto vfree_exit;
>>>> +
>>>> +	cnt = sprintf(buf, "0x");
>>>> +	for (i = 0; i < size; i++)
>>>> +		cnt += sprintf(buf + cnt, "%02x", hash[i]);
>>>> +	cnt += sprintf(buf + cnt, "\n");
>>>> +
>>>> +vfree_exit:
>>>> +	vfree(hash);
>>>> +	return ret ? : cnt;
>>>> +}
>>>> +
>>>> +#define DEVICE_ATTR_SEC_CSK(_name) \
>>>> +static ssize_t _name##_canceled_csks_show(struct device *dev, \
>>>> +					  struct device_attribute *attr, \
>>>> +					  char *buf) \
>>>> +{ \
>>>> +	struct ifpga_sec_mgr *imgr = to_sec_mgr(dev); \
>>>> +	return show_canceled_csk(imgr, \
>>>> +	       imgr->iops->_name##_canceled_csks, \
>>>> +	       imgr->iops->_name##_canceled_csk_nbits, buf); \
>>>> +} \
>>>> +static DEVICE_ATTR_RO(_name##_canceled_csks)
>>>> +
>>>> +#define DEVICE_ATTR_SEC_ROOT_ENTRY_HASH(_name) \
>>>> +static ssize_t _name##_root_entry_hash_show(struct device *dev, \
>>>> +				     struct device_attribute *attr, \
>>>> +				     char *buf) \
>>>> +{ \
>>>> +	struct ifpga_sec_mgr *imgr = to_sec_mgr(dev); \
>>>> +	return show_root_entry_hash(imgr, \
>>>> +	       imgr->iops->_name##_root_entry_hash, \
>>>> +	       imgr->iops->_name##_reh_size, buf); \
>>>> +} \
>>>> +static DEVICE_ATTR_RO(_name##_root_entry_hash)
>>>> +
>>>> +static ssize_t user_flash_count_show(struct device *dev,
>>>> +				     struct device_attribute *attr, char *buf)
>>>> +{
>>>> +	struct ifpga_sec_mgr *imgr = to_sec_mgr(dev);
>>>> +	int cnt = imgr->iops->user_flash_count(imgr);
>>>> +
>>>> +	return cnt < 0 ? cnt : sprintf(buf, "%u\n", cnt);
>>>> +}
>>>> +static DEVICE_ATTR_RO(user_flash_count);
>>>> +
>>>> +DEVICE_ATTR_SEC_ROOT_ENTRY_HASH(sr);
>>>> +DEVICE_ATTR_SEC_ROOT_ENTRY_HASH(pr);
>>>> +DEVICE_ATTR_SEC_ROOT_ENTRY_HASH(bmc);
>>>> +DEVICE_ATTR_SEC_CSK(sr);
>>>> +DEVICE_ATTR_SEC_CSK(pr);
>>>> +DEVICE_ATTR_SEC_CSK(bmc);
>>>> +
>>>> +static struct attribute *sec_mgr_security_attrs[] = {
>>>> +	&dev_attr_user_flash_count.attr,
>>>> +	&dev_attr_bmc_root_entry_hash.attr,
>>>> +	&dev_attr_sr_root_entry_hash.attr,
>>>> +	&dev_attr_pr_root_entry_hash.attr,
>>>> +	&dev_attr_sr_canceled_csks.attr,
>>>> +	&dev_attr_pr_canceled_csks.attr,
>>>> +	&dev_attr_bmc_canceled_csks.attr,
>>>> +	NULL,
>>>> +};
>>>> +
>>>> +#define check_attr(attribute, _name) \
>>>> +	((attribute) == &dev_attr_##_name.attr && imgr->iops->_name)
>>>> +
>>>> +static umode_t sec_mgr_visible(struct kobject *kobj,
>>>> +			       struct attribute *attr, int n)
>>>> +{
>>>> +	struct ifpga_sec_mgr *imgr = to_sec_mgr(kobj_to_dev(kobj));
>>>> +
>>>> +	/*
>>>> +	 * Only display optional sysfs attributes if a
>>>> +	 * corresponding handler is provided
>>>> +	 */
>>>> +	if (check_attr(attr, user_flash_count) ||
>>>> +	    check_attr(attr, bmc_root_entry_hash) ||
>>>> +	    check_attr(attr, sr_root_entry_hash) ||
>>>> +	    check_attr(attr, pr_root_entry_hash) ||
>>>> +	    check_attr(attr, sr_canceled_csks) ||
>>>> +	    check_attr(attr, pr_canceled_csks) ||
>>>> +	    check_attr(attr, bmc_canceled_csks))
>>>> +		return attr->mode;
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>> +static struct attribute_group sec_mgr_security_attr_group = {
>>>> +	.name = "security",
>>>> +	.attrs = sec_mgr_security_attrs,
>>>> +	.is_visible = sec_mgr_visible,
>>>> +};
>>>> +
>>>> +static ssize_t name_show(struct device *dev,
>>>> +			 struct device_attribute *attr, char *buf)
>>>> +{
>>>> +	struct ifpga_sec_mgr *imgr = to_sec_mgr(dev);
>>>> +
>>>> +	return sprintf(buf, "%s\n", imgr->name);
>>>> +}
>>>> +static DEVICE_ATTR_RO(name);
>>>> +
>>>> +static struct attribute *sec_mgr_attrs[] = {
>>>> +	&dev_attr_name.attr,
>>>> +	NULL,
>>>> +};
>>>> +
>>>> +static struct attribute_group sec_mgr_attr_group = {
>>>> +	.attrs = sec_mgr_attrs,
>>>> +};
>>>> +
>>>> +static const struct attribute_group *ifpga_sec_mgr_attr_groups[] = {
>>>> +	&sec_mgr_attr_group,
>>>> +	&sec_mgr_security_attr_group,
>>>> +	NULL,
>>>> +};
>>>> +
>>>> +static bool check_sysfs_handler(struct device *dev,
>>>> +				void *sysfs_handler, void *size_handler,
>>>> +				const char *sysfs_handler_name,
>>>> +				const char *size_handler_name)
>>>> +{
>>>> +	/*
>>>> +	 * sysfs_handler and size_handler must either both be
>>>> +	 * defined or both be NULL.
>>>> +	 */
>>>> +	if (sysfs_handler && !size_handler) {
>>>> +		dev_err(dev, "%s registered without %s\n",
>>>> +			sysfs_handler_name, size_handler_name);
>>>> +		return false;
>>>> +	} else if (!sysfs_handler && size_handler) {
>>>> +		dev_err(dev, "%s registered without %s\n",
>>>> +			size_handler_name, sysfs_handler_name);
>>>> +		return false;
>>>> +	}
>>>> +	return true;
>>>> +}
>>>> +
>>>> +#define check_reh_handler(_dev, _iops, _name) \
>>>> +	check_sysfs_handler(_dev, (_iops)->_name##_root_entry_hash, \
>>>> +			    (_iops)->_name##_reh_size, \
>>>> +			    __stringify(_name##_root_entry_hash), \
>>>> +			    __stringify(_name##_reh_size))
>>>> +
>>>> +#define check_csk_handler(_dev, _iops, _name) \
>>>> +	check_sysfs_handler(_dev, (_iops)->_name##_canceled_csks, \
>>>> +			    (_iops)->_name##_canceled_csk_nbits, \
>>>> +			    __stringify(_name##_canceled_csks), \
>>>> +			    __stringify(_name##_canceled_csk_nbits))
>>>> +
>>>> +/**
>>>> + * ifpga_sec_mgr_create - create and initialize an Intel FPGA
>>>> + *			  security manager struct
>>>> + *
>>>> + * @dev:  Intel fpga security manager device from pdev
>>>> + * @name: ifpga security manager name
>>>> + * @iops: pointer to a structure of ifpga callback functions
>>>> + * @priv: ifpga security manager private data
>>>> + *
>>>> + * The caller of this function is responsible for freeing the struct
>>>> + * with ifpg_sec_mgr_free(). Using devm_ifpga_sec_mgr_create() instead
>>>> + * is recommended.
>>>> + *
>>>> + * Return: pointer to struct ifpga_sec_mgr or NULL
>>>> + */
>>>> +struct ifpga_sec_mgr *
>>>> +ifpga_sec_mgr_create(struct device *dev, const char *name,
>>>> +		     const struct ifpga_sec_mgr_ops *iops, void *priv)
>>>> +{
>>>> +	struct ifpga_sec_mgr *imgr;
>>>> +	int id, ret;
>>>> +
>>>> +	if (!check_reh_handler(dev, iops, bmc) ||
>>>> +	    !check_reh_handler(dev, iops, sr) ||
>>>> +	    !check_reh_handler(dev, iops, pr) ||
>>>> +	    !check_csk_handler(dev, iops, bmc) ||
>>>> +	    !check_csk_handler(dev, iops, sr) ||
>>>> +	    !check_csk_handler(dev, iops, pr)) {
>>>> +		return NULL;
>>>> +	}
>>>> +
>>>> +	if (!name || !strlen(name)) {
>>>> +		dev_err(dev, "Attempt to register with no name!\n");
>>>> +		return NULL;
>>>> +	}
>>>> +
>>>> +	imgr = kzalloc(sizeof(*imgr), GFP_KERNEL);
>>>> +	if (!imgr)
>>>> +		return NULL;
>>>> +
>>>> +	id = ida_simple_get(&ifpga_sec_mgr_ida, 0, 0, GFP_KERNEL);
>>>> +	if (id < 0)
>>>> +		goto error_kfree;
>>>> +
>>>> +	mutex_init(&imgr->lock);
>>>> +
>>>> +	imgr->name = name;
>>>> +	imgr->priv = priv;
>>>> +	imgr->iops = iops;
>>>> +
>>>> +	device_initialize(&imgr->dev);
>>>> +	imgr->dev.class = ifpga_sec_mgr_class;
>>>> +	imgr->dev.parent = dev;
>>>> +	imgr->dev.id = id;
>>>> +
>>>> +	ret = dev_set_name(&imgr->dev, "ifpga_sec%d", id);
>>>> +	if (ret) {
>>>> +		dev_err(dev, "Failed to set device name: ifpga_sec%d\n", id);
>>>> +		goto error_device;
>>>> +	}
>>>> +
>>>> +	return imgr;
>>>> +
>>>> +error_device:
>>>> +	ida_simple_remove(&ifpga_sec_mgr_ida, id);
>>>> +
>>>> +error_kfree:
>>>> +	kfree(imgr);
>>>> +
>>>> +	return NULL;
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(ifpga_sec_mgr_create);
>>>> +
>>>> +/**
>>>> + * ifpga_sec_mgr_free - free an Intel FPGA security manager created
>>>> + *			with ifpga_sec_mgr_create()
>>>> + *
>>>> + * @imgr:	Intel FPGA security manager structure
>>>> + */
>>>> +void ifpga_sec_mgr_free(struct ifpga_sec_mgr *imgr)
>>>> +{
>>>> +	ida_simple_remove(&ifpga_sec_mgr_ida, imgr->dev.id);
>>>> +	kfree(imgr);
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(ifpga_sec_mgr_free);
>>>> +
>>>> +static void devm_ifpga_sec_mgr_release(struct device *dev, void *res)
>>>> +{
>>>> +	struct ifpga_sec_mgr *imgr = *(struct ifpga_sec_mgr **)res;
>>>> +
>>>> +	ifpga_sec_mgr_free(imgr);
>>>> +}
>>>> +
>>>> +/**
>>>> + * devm_ifpga_sec_mgr_create - create and initialize an Intel FPGA
>>>> + *			       security manager struct
>>>> + *
>>>> + * @dev:  Intel fpga security manager device from pdev
>>>> + * @name: ifpga security manager name
>>>> + * @iops: pointer to a structure of ifpga callback functions
>>>> + * @priv: ifpga security manager private data
>>>> + *
>>>> + * This function is intended for use in a Intel FPGA Security manager
>>>> + * driver's probe function.  After the security manager driver creates
>>>> + * the ifpga_sec_mgr struct with devm_fpga_mgr_create(), it should
>>>> + * register it with ifpga_sec_mgr_register().  The security manager
>>>> + * driver's remove function should call ifpga_sec_mgr_unregister().
>>>> + * The ifpga_sec_mgr struct allocated with this function will be freed
>>>> + * automatically on driver detach.  This includes the case of a probe
>>>> + * function returning error before calling fpga_mgr_register(), the
>>>> + * struct will still get cleaned up.
>>>> + *
>>>> + * Return: pointer to struct ifpga_sec_mgr or NULL
>>>> + */
>>>> +struct ifpga_sec_mgr *
>>>> +devm_ifpga_sec_mgr_create(struct device *dev, const char *name,
>>>> +			  const struct ifpga_sec_mgr_ops *iops, void *priv)
>>>> +{
>>>> +	struct ifpga_sec_mgr **ptr, *imgr;
>>>> +
>>>> +	ptr = devres_alloc(devm_ifpga_sec_mgr_release, sizeof(*ptr), GFP_KERNEL);
>>>> +	if (!ptr)
>>>> +		return NULL;
>>>> +
>>>> +	imgr = ifpga_sec_mgr_create(dev, name, iops, priv);
>>>> +	if (!imgr) {
>>>> +		devres_free(ptr);
>>>> +	} else {
>>>> +		*ptr = imgr;
>>>> +		devres_add(dev, ptr);
>>>> +	}
>>>> +
>>>> +	return imgr;
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(devm_ifpga_sec_mgr_create);
>>>> +
>>>> +/**
>>>> + * ifpga_sec_mgr_register - register an Intel FPGA security manager
>>>> + *
>>>> + * @imgr: Intel fpga security manager struct
>>>> + *
>>>> + * Return: 0 on success, negative error code otherwise.
>>>> + */
>>>> +int ifpga_sec_mgr_register(struct ifpga_sec_mgr *imgr)
>>>> +{
>>>> +	int ret;
>>>> +
>>>> +	ret = device_add(&imgr->dev);
>>>> +	if (ret)
>>>> +		goto error_device;
>>>> +
>>>> +	dev_info(&imgr->dev, "%s registered\n", imgr->name);
>>>> +
>>>> +	return 0;
>>>> +
>>>> +error_device:
>>>> +	ida_simple_remove(&ifpga_sec_mgr_ida, imgr->dev.id);
>>>> +
>>>> +	return ret;
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(ifpga_sec_mgr_register);
>>>> +
>>>> +/**
>>>> + * ifpga_sec_mgr_unregister - unregister an Intel FPGA security manager
>>>> + *
>>>> + * @mgr: fpga manager struct
>>>> + *
>>>> + * This function is intended for use in an Intel FPGA security manager
>>>> + * driver's remove() function.
>>>> + */
>>>> +void ifpga_sec_mgr_unregister(struct ifpga_sec_mgr *imgr)
>>>> +{
>>>> +	dev_info(&imgr->dev, "%s %s\n", __func__, imgr->name);
>>>> +
>>>> +	device_unregister(&imgr->dev);
>>>> +}
>>>> +EXPORT_SYMBOL_GPL(ifpga_sec_mgr_unregister);
>>>> +
>>>> +static void ifpga_sec_mgr_dev_release(struct device *dev)
>>>> +{
>>>> +}
>>>> +
>>>> +static int __init ifpga_sec_mgr_class_init(void)
>>>> +{
>>>> +	pr_info("Intel FPGA Security Manager\n");
>>>> +
>>>> +	ifpga_sec_mgr_class = class_create(THIS_MODULE, "ifpga_sec_mgr");
>>>> +	if (IS_ERR(ifpga_sec_mgr_class))
>>>> +		return PTR_ERR(ifpga_sec_mgr_class);
>>>> +
>>>> +	ifpga_sec_mgr_class->dev_groups = ifpga_sec_mgr_attr_groups;
>>>> +	ifpga_sec_mgr_class->dev_release = ifpga_sec_mgr_dev_release;
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>> +static void __exit ifpga_sec_mgr_class_exit(void)
>>>> +{
>>>> +	class_destroy(ifpga_sec_mgr_class);
>>>> +	ida_destroy(&ifpga_sec_mgr_ida);
>>>> +}
>>>> +
>>>> +MODULE_DESCRIPTION("Intel FPGA Security Manager Driver");
>>>> +MODULE_LICENSE("GPL v2");
>>>> +
>>>> +subsys_initcall(ifpga_sec_mgr_class_init);
>>>> +module_exit(ifpga_sec_mgr_class_exit)
>>>> diff --git a/include/linux/fpga/ifpga-sec-mgr.h b/include/linux/fpga/ifpga-sec-mgr.h
>>>> new file mode 100644
>>>> index 000000000000..ded62090e9b9
>>>> --- /dev/null
>>>> +++ b/include/linux/fpga/ifpga-sec-mgr.h
>>>> @@ -0,0 +1,81 @@
>>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>>> +/*
>>>> + * Header file for Intel FPGA Security Manager
>>>> + *
>>>> + * Copyright (C) 2019-2020 Intel Corporation, Inc.
>>>> + */
>>>> +#ifndef _LINUX_IFPGA_SEC_MGR_H
>>>> +#define _LINUX_IFPGA_SEC_MGR_H
>>>> +
>>>> +#include <linux/device.h>
>>>> +#include <linux/mutex.h>
>>>> +#include <linux/types.h>
>>>> +
>>>> +struct ifpga_sec_mgr;
>>>> +
>>>> +/**
>>>> + * struct ifpga_sec_mgr_ops - device specific operations
>>>> + * @user_flash_count:	    Optional: Return sysfs string output for FPGA
>>>> + *			    image flash count
>>>> + * @sr_root_entry_hash:	    Optional: Return sysfs string output for static
>>>> + *			    region root entry hash
>>>> + * @pr_root_entry_hash:	    Optional: Return sysfs string output for partial
>>>> + *			    reconfiguration root entry hash
>>>> + * @bmc_root_entry_hash:    Optional: Return sysfs string output for BMC
>>>> + *			    root entry hash
>>>> + * @sr_canceled_csks:	    Optional: Return sysfs string output for static
>>>> + *			    region canceled keys
>>>> + * @pr_canceled_csks:	    Optional: Return sysfs string output for partial
>>>> + *			    reconfiguration canceled keys
>>>> + * @bmc_canceled_csks:	    Optional: Return sysfs string output for bmc
>>>> + *			    canceled keys
>>>> + * @bmc_canceled_csk_nbits: Optional: Return BMC canceled csk vector bit count
>>>> + * @sr_canceled_csk_nbits:  Optional: Return SR canceled csk vector bit count
>>>> + * @pr_canceled_csk_nbits:  Optional: Return PR canceled csk vector bit count
>>>> + * @bmc_reh_size:	    Optional: Return byte size for BMC root entry hash
>>>> + * @sr_reh_size:	    Optional: Return byte size for SR root entry hash
>>>> + * @pr_reh_size:	    Optional: Return byte size for PR root entry hash
>>>> + */
>>>> +struct ifpga_sec_mgr_ops {
>>>> +	int (*user_flash_count)(struct ifpga_sec_mgr *imgr);
>>>> +	int (*bmc_root_entry_hash)(struct ifpga_sec_mgr *imgr, u8 *hash,
>>>> +				   unsigned int size);
>>>> +	int (*sr_root_entry_hash)(struct ifpga_sec_mgr *imgr, u8 *hash,
>>>> +				  unsigned int size);
>>>> +	int (*pr_root_entry_hash)(struct ifpga_sec_mgr *imgr, u8 *hash,
>>>> +				  unsigned int size);
>>>> +	int (*bmc_canceled_csks)(struct ifpga_sec_mgr *imgr,
>>>> +				 unsigned long *csk_map, unsigned int nbits);
>>>> +	int (*sr_canceled_csks)(struct ifpga_sec_mgr *imgr,
>>>> +				unsigned long *csk_map, unsigned int nbits);
>>>> +	int (*pr_canceled_csks)(struct ifpga_sec_mgr *imgr,
>>>> +				unsigned long *csk_map, unsigned int nbits);
>>>> +	int (*bmc_reh_size)(struct ifpga_sec_mgr *imgr);
>>>> +	int (*sr_reh_size)(struct ifpga_sec_mgr *imgr);
>>>> +	int (*pr_reh_size)(struct ifpga_sec_mgr *imgr);
>>>> +	int (*bmc_canceled_csk_nbits)(struct ifpga_sec_mgr *imgr);
>>>> +	int (*sr_canceled_csk_nbits)(struct ifpga_sec_mgr *imgr);
>>>> +	int (*pr_canceled_csk_nbits)(struct ifpga_sec_mgr *imgr);
>>>> +};
>>>> +
>>>> +struct ifpga_sec_mgr {
>>>> +	const char *name;
>>>> +	struct device dev;
>>>> +	const struct ifpga_sec_mgr_ops *iops;
>>>> +	struct mutex lock;		/* protect data structure contents */
>>>> +	void *priv;
>>>> +};
>>>> +
>>>> +struct ifpga_sec_mgr *
>>>> +ifpga_sec_mgr_create(struct device *dev, const char *name,
>>>> +		     const struct ifpga_sec_mgr_ops *iops, void *priv);
>>>> +
>>>> +struct ifpga_sec_mgr *
>>>> +devm_ifpga_sec_mgr_create(struct device *dev, const char *name,
>>>> +			  const struct ifpga_sec_mgr_ops *iops, void *priv);
>>>> +
>>>> +int ifpga_sec_mgr_register(struct ifpga_sec_mgr *imgr);
>>>> +void ifpga_sec_mgr_unregister(struct ifpga_sec_mgr *imgr);
>>>> +void ifpga_sec_mgr_free(struct ifpga_sec_mgr *imgr);
>>>> +
>>>> +#endif
>>>> -- 
>>>> 2.17.1
>>>>
>>> Thanks,
>>> Moritz
> Thanks,
> Moritz