From:   Chen Yu <yu.c.chen@intel.com>
To:     linux-acpi@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Ard Biesheuvel <ardb@kernel.org>, Len Brown <lenb@kernel.org>,
        Ashok Raj <ashok.raj@intel.com>,
        Andy Shevchenko <andriy.shevchenko@intel.com>,
        Mike Rapoport <rppt@kernel.org>, Chen Yu <yu.c.chen@intel.com>,
        linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org
Subject: [PATCH v11 1/4] efi: Introduce EFI_FIRMWARE_MANAGEMENT_CAPSULE_HEADER and corresponding structures
Date:   Sun, 21 Nov 2021 23:16:07 +0800
Message-Id: <6774dd4cce68a68b1ac54df3dfd295bb4b04bf2b.1637505679.git.yu.c.chen@intel.com>
In-Reply-To: <cover.1637505679.git.yu.c.chen@intel.com>
References: <cover.1637505679.git.yu.c.chen@intel.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Platform Firmware Runtime Update image starts with UEFI headers, and the
headers are defined in UEFI specification, but some of them have not been
defined in the kernel yet.

For example, the header layout of a capsule file looks like this:

EFI_CAPSULE_HEADER
EFI_FIRMWARE_MANAGEMENT_CAPSULE_HEADER
EFI_FIRMWARE_MANAGEMENT_CAPSULE_IMAGE_HEADER
EFI_FIRMWARE_IMAGE_AUTHENTICATION

These structures would be used by the Platform Firmware Runtime Update
driver to parse the format of capsule file to verify if the corresponding
version number is valid. In this way, if the user provides an invalid
capsule image, the kernel could be used as a guard to reject it, without
switching to the Management Mode (which might be costly).

EFI_CAPSULE_HEADER has been defined in the kernel, but the other
structures have not been defined yet, so do that. Besides,
EFI_FIRMWARE_MANAGEMENT_CAPSULE_HEADER and
EFI_FIRMWARE_MANAGEMENT_CAPSULE_IMAGE_HEADER are required to be packed
in the uefi specification. For this reason, use the __packed attribute
to indicate to the compiler that the entire structure can appear
misaligned in memory (as suggested by Ard) in case one of them follows
the other directly in a capsule header.

Signed-off-by: Chen Yu <yu.c.chen@intel.com>
---
v11:Add explanation on why version check is introduced
    in kernel rather than letting Management Mode to do it.
    (Rafael J. Wysocki)
    Revise the commit log to better describe the pack attribute.
    (Rafael J. Wysocki)
    Refine the comment for hw_ins and capsule_support.
    (Rafael J. Wysocki)
v10:Remove the explicit assignment of the last item of enum.
    (Andy Shevchenko)
v9: Use GUID_INIT() instead of guid_parse() during boot up.
    (Andy Shevchenko)
    Drop uuid, code_uuid, drv_uuid in struct pfru_device as they
    are not needed. (Andy Shevchenko)
    Drop type casting from void * in valid_version().
    (Andy Shevchenko)
    Use kfree() instead of ACPI_FREE() in non-ACPICA usage.
    (Andy Shevchenko)
    Use sizeof(rev) instead of sizeof(u32) in copy_from_user().
    (Andy Shevchenko)
    Generate physical address from MSB part to LSB.
    (Andy Shevchenko)
    Use devm_add_action_or_reset() to add ida release into dev resource
    management. (Andy Shevchenko)
    Use devm_kasprintf() instead of kasprintf() to format the
    pfru_dev name.(Andy Shevchenko)
    Remove redundant 0 in acpi_pfru_ids. (Andy Shevchenko)
    Adjust the order of included headers in pfru.h.
    (Andy Shevchenko)
    Replace PFRU_MAGIC with PFRU_MAGIC_FOR_IOCTL in uapi file.
    (Andy Shevchenko)
v8: Remove the variable-length array in struct pfru_update_cap_info, and
    copy the non-variable-length struct pfru_update_cap_info to userspace
    directly. (Greg Kroah-Hartman)
    Change the type of rev_id from int to u32, because this data will
    be copied between kernel and userspace. (Greg Kroah-Hartman)
    Add a prefix for dev in struct pfru_device to parent_dev, so as
    to indicate that this filed is the parent of the created miscdev.
    (Greg Kroah-Hartman)
    Use blank lines between different macro sections. (Greg Kroah-Hartman)
    Illusatrate the possible errno for each ioctl interface.
    (Greg Kroah-Hartman)
    Remove pfru_valid_revid() from uapi header to avoid poluting the global
    namespace.(Greg Kroah-Hartman)
    Assign the value to the enum type explicitly.(Greg Kroah-Hartman)
    Change the guid_t to efi_guid_t when parsing image header in get_image_type()
    (Greg Kroah-Hartman)
    Remove the void * to other type casting in valid_version(). (Andy Shevchenko)
    Combined the assignment of variables with definitions. (Andy Shevchenko)
    Define this magic for revision ID. (Andy Shevchenko)
    Make the labeling consistent for error handling. (Andy Shevchenko)
    Replace the UUID_SIZE in uapi with 16 directly. (Andy Shevchenko)
    Add blank line between generic include header and uapi header.
    (Andy Shevchenko)
    Arrange the order between devm_kzalloc() and normal allocation in
    acpi_pfru_probe() that, the former should always be ahead of the
    latter. (Andy Shevchenko)
    Move the UUID from uapi header to the c file. (Andy Shevchenko)
v7: Use ida_alloc() to allocate a ID, and release the ID when
    device is removed. (Greg Kroah-Hartman)
    Check the _DSM method at early stage, before allocate or parse
    anything in acpi_pfru_probe(). (Greg Kroah-Hartman)
    Set the parent of the misc device. (Greg Kroah-Hartman)
    Use module_platform_driver() instead of platform_driver_register()
    in module_init(). Separate pfru driver and pfru_telemetry driver
    to two files. (Greg Kroah-Hartman) 
v6: Use Link: tag to add the specification download address.
    (Andy Shevchenko)
    Remove linux/uuid.h and use raw buffers to contain uuid.
    (Andy Shevchenko)
    Drop comma for each terminator entry in the enum structure.
    (Andy Shevchenko)
    Remove redundant 'else' in get_image_type().
    (Andy Shevchenko)
    Directly return results from the switch cases in adjust_efi_size()
    and pfru_ioctl().(Andy Shevchenko)
    Keep comment style consistent by removing the period for
    one line comment.
    (Andy Shevchenko)
    Remove devm_kfree() if .probe() failed. 
    (Andy Shevchenko)
v5: Remove Documentation/ABI/pfru, and move the content to kernel doc
    in include/uapi/linux/pfru.h (Greg Kroah-Hartman)
    Shrink the range of ioctl numbers declared in
    Documentation/userspace-api/ioctl/ioctl-number.rst
    from 16 to 8. (Greg Kroah-Hartman)
    Change global variable struct pfru_device *pfru_dev to
    per ACPI device. (Greg Kroah-Hartman)
    Unregister the misc device in acpi_pfru_remove().
    (Greg Kroah-Hartman)
    Convert the kzalloc() to devm_kzalloc() in the driver so
    as to avoid freeing the memory. (Greg Kroah-Hartman)
    Fix the compile error by declaring the pfru_log_ioctl() as
    static. (kernel test robot LKP)
    Change to global variable misc_device to per ACPI device.
    (Greg Kroah-Hartman)
v4: Replace all pr_err() with dev_dbg() (Greg Kroah-Hartman,
    Rafael J. Wysocki)
    Returns ENOTTY rather than ENOIOCTLCMD if invalid ioctl command
    is provided. (Greg Kroah-Hartman)
    Remove compat ioctl. (Greg Kroah-Hartman)
    Rename /dev/pfru/pfru_update to /dev/acpi_pfru (Greg Kroah-Hartman)
    Simplify the check for element of the package in query_capability()
    (Rafael J. Wysocki)
    Remove the loop in query_capability(), query_buffer() and query
    the package elemenet directly. (Rafael J. Wysocki)
    Check the the number of elements in case the number of package
    elements is too small. (Rafael J. Wysocki)
    Doing the assignment as initialization in get_image_type().
    Meanwhile, returns the type or a negative error code in
    get_image_type(). (Rafael J. Wysocki)
    Put the comments inside the function. (Rafael J. Wysocki)
    Returns the size or a negative error code in adjust_efi_size()
    (Rafael J. Wysocki)
    Fix the return value from EFAULT to EINVAL if pfru_valid_revid()
    does not pass. (Rafael J. Wysocki)
    Change the write() to be the code injection/update, the read() to
    be telemetry retrieval and all of the rest to be ioctl()s under
    one special device file.(Rafael J. Wysocki)
    Putting empty code lines after an if () statement that is not
    followed by a block. (Rafael J. Wysocki)
    Remove "goto" tags to make the code more readable. (Rafael J. Wysocki)
v3: Use __u32 instead of int and __64 instead of unsigned long
    in include/uapi/linux/pfru.h (Greg Kroah-Hartman)
    Rename the structure in uapi to start with a prefix pfru so as
    to avoid confusing in the global namespace. (Greg Kroah-Hartman)
v2: Add sanity check for duplicated instance of ACPI device.
    Update the driver to work with allocated pfru_device objects.
    (Mike Rapoport)
    For each switch case pair, get rid of the magic case numbers
    and add a default clause with the error handling.
    (Mike Rapoport)
    Move the obj->type checks outside the switch to reduce redundancy.
    (Mike Rapoport)
    Parse the code_inj_id and drv_update_id at driver initialization time
    to reduce the re-parsing at runtime.(Mike Rapoport)
    Explain in detail how the size needs to be adjusted when doing
    version check.(Mike Rapoport)
    Rename parse_update_result() to dump_update_result()(Mike Rapoport)
    Remove redundant return.(Mike Rapoport)
    Do not expose struct capsulate_buf_info to uapi, since it is
    not needed in userspace.(Mike Rapoport)
---
 include/linux/efi.h | 46 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/include/linux/efi.h b/include/linux/efi.h
index dbd39b20e034..80e970f7e6f8 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -148,6 +148,52 @@ typedef struct {
 	u32 imagesize;
 } efi_capsule_header_t;
 
+/* EFI_FIRMWARE_MANAGEMENT_CAPSULE_HEADER */
+struct efi_manage_capsule_header {
+	u32 ver;
+	u16 emb_drv_cnt;
+	u16 payload_cnt;
+	/*
+	 * Variable-size array of the size given by the sum of
+	 * emb_drv_cnt and payload_cnt.
+	 */
+	u64 offset_list[];
+} __packed;
+
+/* EFI_FIRMWARE_MANAGEMENT_CAPSULE_IMAGE_HEADER */
+struct efi_manage_capsule_image_header {
+	u32 ver;
+	efi_guid_t image_type_id;
+	u8 image_index;
+	u8 reserved_bytes[3];
+	u32 image_size;
+	u32 vendor_code_size;
+	/* hw_ins was introduced in version 2 */
+	u64 hw_ins;
+	/* capsule_support was introduced in version 3 */
+	u64 capsule_support;
+} __packed;
+
+/* WIN_CERTIFICATE */
+struct win_cert {
+	u32 len;
+	u16 rev;
+	u16 cert_type;
+};
+
+/* WIN_CERTIFICATE_UEFI_GUID */
+struct win_cert_uefi_guid {
+	struct win_cert	hdr;
+	efi_guid_t cert_type;
+	u8 cert_data[];
+};
+
+/* EFI_FIRMWARE_IMAGE_AUTHENTICATION */
+struct efi_image_auth {
+	u64 mon_count;
+	struct win_cert_uefi_guid auth_info;
+};
+
 /*
  * EFI capsule flags
  */
-- 
2.25.1