cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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fakekey.c (1805B)

      1// SPDX-License-Identifier: GPL-2.0+
      2/* fakekey.c
      3 * Functions for simulating key presses.
      4 *
      5 * Copyright (C) 2010 the Speakup Team
      6 */
      7#include <linux/types.h>
      8#include <linux/slab.h>
      9#include <linux/preempt.h>
     10#include <linux/percpu.h>
     11#include <linux/input.h>
     12
     13#include "speakup.h"
     14
     15#define PRESSED 1
     16#define RELEASED 0
     17
     18static DEFINE_PER_CPU(int, reporting_keystroke);
     19
     20static struct input_dev *virt_keyboard;
     21
     22int speakup_add_virtual_keyboard(void)
     23{
     24	int err;
     25
     26	virt_keyboard = input_allocate_device();
     27
     28	if (!virt_keyboard)
     29		return -ENOMEM;
     30
     31	virt_keyboard->name = "Speakup";
     32	virt_keyboard->id.bustype = BUS_VIRTUAL;
     33	virt_keyboard->phys = "speakup/input0";
     34	virt_keyboard->dev.parent = NULL;
     35
     36	__set_bit(EV_KEY, virt_keyboard->evbit);
     37	__set_bit(KEY_DOWN, virt_keyboard->keybit);
     38
     39	err = input_register_device(virt_keyboard);
     40	if (err) {
     41		input_free_device(virt_keyboard);
     42		virt_keyboard = NULL;
     43	}
     44
     45	return err;
     46}
     47
     48void speakup_remove_virtual_keyboard(void)
     49{
     50	if (virt_keyboard) {
     51		input_unregister_device(virt_keyboard);
     52		virt_keyboard = NULL;
     53	}
     54}
     55
     56/*
     57 * Send a simulated down-arrow to the application.
     58 */
     59void speakup_fake_down_arrow(void)
     60{
     61	unsigned long flags;
     62
     63	/* disable keyboard interrupts */
     64	local_irq_save(flags);
     65	/* don't change CPU */
     66	preempt_disable();
     67
     68	__this_cpu_write(reporting_keystroke, true);
     69	input_report_key(virt_keyboard, KEY_DOWN, PRESSED);
     70	input_report_key(virt_keyboard, KEY_DOWN, RELEASED);
     71	input_sync(virt_keyboard);
     72	__this_cpu_write(reporting_keystroke, false);
     73
     74	/* reenable preemption */
     75	preempt_enable();
     76	/* reenable keyboard interrupts */
     77	local_irq_restore(flags);
     78}
     79
     80/*
     81 * Are we handling a simulated key press on the current CPU?
     82 * Returns a boolean.
     83 */
     84bool speakup_fake_key_pressed(void)
     85{
     86	return this_cpu_read(reporting_keystroke);
     87}