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

From: Russ Weight
Date: Wed Oct 07 2020 - 12:43:36 EST




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
>> +========================================
>> +
>> +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