mirror of
https://github.com/torvalds/linux.git
synced 2026-09-24 06:24:02 +02:00
65f0ecb9ec
The ISSEI (Intel Silicon Security Engine Interface) subsystem provides a communication channel between the host and the Silicon Security Engine. Prepare basic driver functions and character device for user-space communication. Add DMA access routines for ISSEI HECI devices. Add of DMA-related structures and implementation of routines for setting up DMA, as well as reading and writing DMA buffers. Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com> Co-developed-by: Vitaly Lubart <lubvital@gmail.com> Signed-off-by: Vitaly Lubart <lubvital@gmail.com> Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Link: https://patch.msgid.link/20260513-issei-for-upstream-v1-1-f590038678f9@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
136 lines
4.5 KiB
ReStructuredText
136 lines
4.5 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
|
|
|
|
Introduction
|
|
============
|
|
|
|
The Intel Silicon Security Engine (Intel SSE) is an isolated and
|
|
protected computing resource (Co-processor) residing inside
|
|
Intel client chipsets released in 2024 (Lunar Lake) or later.
|
|
The Intel SSE provide security support and platform boot orchestration.
|
|
The actual feature set depends on the Intel chipset SKU.
|
|
|
|
The Intel Silicon Security Engine Interface (Intel SSEI)
|
|
is the interface between the Host and Intel SSE.
|
|
This interface is exposed to the host as one or more PCI devices.
|
|
The Intel SSEI Driver is in charge of the communication channel between
|
|
a host application and the Intel SSE features.
|
|
|
|
Each Intel SSE feature, or Intel SSE Client is addressed by a unique UUID and
|
|
each client has its own protocol. The protocol is message-based with a
|
|
header and payload up to maximal number of bytes advertised by the client,
|
|
upon connection.
|
|
|
|
Intel SSEI Driver
|
|
=================
|
|
|
|
The driver exposes a character device with device nodes /dev/isseiX.
|
|
|
|
An application maintains communication with an Intel SSE feature while
|
|
/dev/isseiX is open. The binding to a specific feature is performed by calling
|
|
:c:macro:`IOCTL_ISSEI_CONNECT_CLIENT`, which passes the desired UUID.
|
|
The number of instances of an Intel SSE feature that can be opened
|
|
at the same time is limited to single instance.
|
|
|
|
The driver is transparent to data that are passed between firmware feature
|
|
and host application.
|
|
|
|
Because some of the Intel SSE features can change the system
|
|
configuration, the driver by default allows only a privileged
|
|
user to access it.
|
|
|
|
The connection termination is performed by calling
|
|
:c:macro:`IOCTL_ISSEI_DISCONNECT_CLIENT`.
|
|
|
|
The session is terminated calling :c:expr:`close(fd)`.
|
|
|
|
A code snippet for an application communicating with SPDM client:
|
|
|
|
.. code-block:: C
|
|
|
|
struct issei_connect_client_data data = {.in_client_uuid =
|
|
{0xe8, 0x51, 0x49, 0xdf, 0x94, 0x47, 0x4C,
|
|
0x9A, 0x83, 0x67, 0xC4, 0xE3, 0x34, 0x64, 0xF1, 0xB4}};
|
|
__u8 req_data[] = {0x10, 0x84, 0x00, 0x00}; /* SPDM Get Version */
|
|
size_t req_data_len = sizeof(req_data);
|
|
__u8 res_data[256];
|
|
size_t res_data_len = sizeof(res_data);
|
|
int fd = open("/dev/issei0", O_RDWR);
|
|
|
|
ioctl(fd, IOCTL_ISSEI_CONNECT_CLIENT, &data);
|
|
|
|
printf("Ver=%d, MaxLen=%u, Flags=0x%08X\n",
|
|
data.out_client_properties.protocol_version,
|
|
data.out_client_properties.max_msg_length,
|
|
data.out_client_properties.flags);
|
|
|
|
[...]
|
|
|
|
write(fd, req_data, req_data_len);
|
|
|
|
[...]
|
|
|
|
read(fd, res_data, res_data_len);
|
|
|
|
printf("SPDM version count %u, version[0]=%02X%02X\n",
|
|
res_data[5], res_data[6], res_data[7]);
|
|
|
|
[...]
|
|
|
|
ioctl(fd, IOCTL_ISSEI_DISCONNECT_CLIENT, &data);
|
|
|
|
[...]
|
|
|
|
close(fd);
|
|
|
|
|
|
User space API ioctl
|
|
====================
|
|
|
|
The Intel SSEI Driver supports the following ioctl commands:
|
|
|
|
IOCTL_ISSEI_CONNECT_CLIENT
|
|
--------------------------
|
|
Connect to firmware Feature/Client.
|
|
|
|
.. code-block:: none
|
|
|
|
Usage:
|
|
|
|
struct issei_connect_client_data client_data;
|
|
|
|
ioctl(fd, IOCTL_ISSEI_CONNECT_CLIENT, &client_data);
|
|
|
|
struct issei_connect_client_data - contain the following
|
|
Inputs:
|
|
in_client_uuid - UUID of the FW Feature that needs to connect to.
|
|
Outputs:
|
|
out_client_properties - Client Properties: MTU, Protocol Version and Flags.
|
|
|
|
Error returns:
|
|
ENOTTY No such client (i.e. wrong UUID) or connection is not allowed.
|
|
EINVAL Wrong IOCTL Number
|
|
ENODEV Device or Connection is not initialized or ready.
|
|
ENOMEM Unable to allocate memory to client internal data.
|
|
EFAULT Fatal Error (e.g. Unable to access user input data)
|
|
EBUSY Connection Already Open
|
|
|
|
:Note:
|
|
max_msg_length (MTU) in client properties describes the maximum
|
|
data that can be sent or received. (e.g. with MTU=2K, can send
|
|
requests up to bytes 2k and received responses up to 2k bytes).
|
|
|
|
IOCTL_ISSEI_DISCONNECT_CLIENT
|
|
-----------------------------
|
|
Disconnect from firmware Feature/Client.
|
|
|
|
.. code-block:: none
|
|
|
|
Usage:
|
|
|
|
ioctl(fd, IOCTL_ISSEI_DISCONNECT_CLIENT, NULL);
|
|
|
|
Error returns:
|
|
EINVAL Wrong IOCTL Number
|
|
ENODEV Device or Connection is not initialized or ready.
|
|
ENOTCONN Feature/Client is not connected.
|