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1/*
2 * User level driver support for input subsystem
3 *
4 * Heavily based on evdev.c by Vojtech Pavlik
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
21 *
22 * Changes/Revisions:
23 * 0.4 01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
24 * - add UI_GET_SYSNAME ioctl
25 * 0.3 09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
26 * - updated ff support for the changes in kernel interface
27 * - added MODULE_VERSION
28 * 0.2 16/10/2004 (Micah Dowty <micah@navi.cx>)
29 * - added force feedback support
30 * - added UI_SET_PHYS
31 * 0.1 20/06/2002
32 * - first public version
33 */
34#include <linux/poll.h>
35#include <linux/sched.h>
36#include <linux/slab.h>
37#include <linux/module.h>
38#include <linux/init.h>
39#include <linux/fs.h>
40#include <linux/miscdevice.h>
41#include <linux/uinput.h>
42#include <linux/input/mt.h>
43#include "../input-compat.h"
44
45static int uinput_dev_event(struct input_dev *dev,
46 unsigned int type, unsigned int code, int value)
47{
48 struct uinput_device *udev = input_get_drvdata(dev);
49
50 udev->buff[udev->head].type = type;
51 udev->buff[udev->head].code = code;
52 udev->buff[udev->head].value = value;
53 do_gettimeofday(&udev->buff[udev->head].time);
54 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
55
56 wake_up_interruptible(&udev->waitq);
57
58 return 0;
59}
60
61/* Atomically allocate an ID for the given request. Returns 0 on success. */
62static bool uinput_request_alloc_id(struct uinput_device *udev,
63 struct uinput_request *request)
64{
65 unsigned int id;
66 bool reserved = false;
67
68 spin_lock(&udev->requests_lock);
69
70 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
71 if (!udev->requests[id]) {
72 request->id = id;
73 udev->requests[id] = request;
74 reserved = true;
75 break;
76 }
77 }
78
79 spin_unlock(&udev->requests_lock);
80 return reserved;
81}
82
83static struct uinput_request *uinput_request_find(struct uinput_device *udev,
84 unsigned int id)
85{
86 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
87 if (id >= UINPUT_NUM_REQUESTS)
88 return NULL;
89
90 return udev->requests[id];
91}
92
93static int uinput_request_reserve_slot(struct uinput_device *udev,
94 struct uinput_request *request)
95{
96 /* Allocate slot. If none are available right away, wait. */
97 return wait_event_interruptible(udev->requests_waitq,
98 uinput_request_alloc_id(udev, request));
99}
100
101static void uinput_request_done(struct uinput_device *udev,
102 struct uinput_request *request)
103{
104 /* Mark slot as available */
105 udev->requests[request->id] = NULL;
106 wake_up(&udev->requests_waitq);
107
108 complete(&request->done);
109}
110
111static int uinput_request_send(struct uinput_device *udev,
112 struct uinput_request *request)
113{
114 int retval;
115
116 retval = mutex_lock_interruptible(&udev->mutex);
117 if (retval)
118 return retval;
119
120 if (udev->state != UIST_CREATED) {
121 retval = -ENODEV;
122 goto out;
123 }
124
125 init_completion(&request->done);
126
127 /*
128 * Tell our userspace application about this new request
129 * by queueing an input event.
130 */
131 uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
132
133 out:
134 mutex_unlock(&udev->mutex);
135 return retval;
136}
137
138static int uinput_request_submit(struct uinput_device *udev,
139 struct uinput_request *request)
140{
141 int error;
142
143 error = uinput_request_reserve_slot(udev, request);
144 if (error)
145 return error;
146
147 error = uinput_request_send(udev, request);
148 if (error) {
149 uinput_request_done(udev, request);
150 return error;
151 }
152
153 wait_for_completion(&request->done);
154 return request->retval;
155}
156
157/*
158 * Fail all outstanding requests so handlers don't wait for the userspace
159 * to finish processing them.
160 */
161static void uinput_flush_requests(struct uinput_device *udev)
162{
163 struct uinput_request *request;
164 int i;
165
166 spin_lock(&udev->requests_lock);
167
168 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
169 request = udev->requests[i];
170 if (request) {
171 request->retval = -ENODEV;
172 uinput_request_done(udev, request);
173 }
174 }
175
176 spin_unlock(&udev->requests_lock);
177}
178
179static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
180{
181 uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
182}
183
184static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
185{
186 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
187}
188
189static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
190{
191 return uinput_dev_event(dev, EV_FF, effect_id, value);
192}
193
194static int uinput_dev_upload_effect(struct input_dev *dev,
195 struct ff_effect *effect,
196 struct ff_effect *old)
197{
198 struct uinput_device *udev = input_get_drvdata(dev);
199 struct uinput_request request;
200
201 /*
202 * uinput driver does not currently support periodic effects with
203 * custom waveform since it does not have a way to pass buffer of
204 * samples (custom_data) to userspace. If ever there is a device
205 * supporting custom waveforms we would need to define an additional
206 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
207 */
208 if (effect->type == FF_PERIODIC &&
209 effect->u.periodic.waveform == FF_CUSTOM)
210 return -EINVAL;
211
212 request.code = UI_FF_UPLOAD;
213 request.u.upload.effect = effect;
214 request.u.upload.old = old;
215
216 return uinput_request_submit(udev, &request);
217}
218
219static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
220{
221 struct uinput_device *udev = input_get_drvdata(dev);
222 struct uinput_request request;
223
224 if (!test_bit(EV_FF, dev->evbit))
225 return -ENOSYS;
226
227 request.code = UI_FF_ERASE;
228 request.u.effect_id = effect_id;
229
230 return uinput_request_submit(udev, &request);
231}
232
233static void uinput_destroy_device(struct uinput_device *udev)
234{
235 const char *name, *phys;
236 struct input_dev *dev = udev->dev;
237 enum uinput_state old_state = udev->state;
238
239 udev->state = UIST_NEW_DEVICE;
240
241 if (dev) {
242 name = dev->name;
243 phys = dev->phys;
244 if (old_state == UIST_CREATED) {
245 uinput_flush_requests(udev);
246 input_unregister_device(dev);
247 } else {
248 input_free_device(dev);
249 }
250 kfree(name);
251 kfree(phys);
252 udev->dev = NULL;
253 }
254}
255
256static int uinput_create_device(struct uinput_device *udev)
257{
258 struct input_dev *dev = udev->dev;
259 int error, nslot;
260
261 if (udev->state != UIST_SETUP_COMPLETE) {
262 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
263 return -EINVAL;
264 }
265
266 if (test_bit(ABS_MT_SLOT, dev->absbit)) {
267 nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
268 error = input_mt_init_slots(dev, nslot, 0);
269 if (error)
270 goto fail1;
271 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
272 input_set_events_per_packet(dev, 60);
273 }
274
275 if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
276 printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
277 UINPUT_NAME);
278 error = -EINVAL;
279 goto fail1;
280 }
281
282 if (udev->ff_effects_max) {
283 error = input_ff_create(dev, udev->ff_effects_max);
284 if (error)
285 goto fail1;
286
287 dev->ff->upload = uinput_dev_upload_effect;
288 dev->ff->erase = uinput_dev_erase_effect;
289 dev->ff->playback = uinput_dev_playback;
290 dev->ff->set_gain = uinput_dev_set_gain;
291 dev->ff->set_autocenter = uinput_dev_set_autocenter;
292 }
293
294 error = input_register_device(udev->dev);
295 if (error)
296 goto fail2;
297
298 udev->state = UIST_CREATED;
299
300 return 0;
301
302 fail2: input_ff_destroy(dev);
303 fail1: uinput_destroy_device(udev);
304 return error;
305}
306
307static int uinput_open(struct inode *inode, struct file *file)
308{
309 struct uinput_device *newdev;
310
311 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
312 if (!newdev)
313 return -ENOMEM;
314
315 mutex_init(&newdev->mutex);
316 spin_lock_init(&newdev->requests_lock);
317 init_waitqueue_head(&newdev->requests_waitq);
318 init_waitqueue_head(&newdev->waitq);
319 newdev->state = UIST_NEW_DEVICE;
320
321 file->private_data = newdev;
322 nonseekable_open(inode, file);
323
324 return 0;
325}
326
327static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
328 const struct input_absinfo *abs)
329{
330 int min, max;
331
332 min = abs->minimum;
333 max = abs->maximum;
334
335 if ((min != 0 || max != 0) && max <= min) {
336 printk(KERN_DEBUG
337 "%s: invalid abs[%02x] min:%d max:%d\n",
338 UINPUT_NAME, code, min, max);
339 return -EINVAL;
340 }
341
342 if (abs->flat > max - min) {
343 printk(KERN_DEBUG
344 "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
345 UINPUT_NAME, code, abs->flat, min, max);
346 return -EINVAL;
347 }
348
349 return 0;
350}
351
352static int uinput_validate_absbits(struct input_dev *dev)
353{
354 unsigned int cnt;
355 int error;
356
357 if (!test_bit(EV_ABS, dev->evbit))
358 return 0;
359
360 /*
361 * Check if absmin/absmax/absfuzz/absflat are sane.
362 */
363
364 for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
365 if (!dev->absinfo)
366 return -EINVAL;
367
368 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
369 if (error)
370 return error;
371 }
372
373 return 0;
374}
375
376static int uinput_allocate_device(struct uinput_device *udev)
377{
378 udev->dev = input_allocate_device();
379 if (!udev->dev)
380 return -ENOMEM;
381
382 udev->dev->event = uinput_dev_event;
383 input_set_drvdata(udev->dev, udev);
384
385 return 0;
386}
387
388static int uinput_dev_setup(struct uinput_device *udev,
389 struct uinput_setup __user *arg)
390{
391 struct uinput_setup setup;
392 struct input_dev *dev;
393
394 if (udev->state == UIST_CREATED)
395 return -EINVAL;
396
397 if (copy_from_user(&setup, arg, sizeof(setup)))
398 return -EFAULT;
399
400 if (!setup.name[0])
401 return -EINVAL;
402
403 dev = udev->dev;
404 dev->id = setup.id;
405 udev->ff_effects_max = setup.ff_effects_max;
406
407 kfree(dev->name);
408 dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
409 if (!dev->name)
410 return -ENOMEM;
411
412 udev->state = UIST_SETUP_COMPLETE;
413 return 0;
414}
415
416static int uinput_abs_setup(struct uinput_device *udev,
417 struct uinput_setup __user *arg, size_t size)
418{
419 struct uinput_abs_setup setup = {};
420 struct input_dev *dev;
421 int error;
422
423 if (size > sizeof(setup))
424 return -E2BIG;
425
426 if (udev->state == UIST_CREATED)
427 return -EINVAL;
428
429 if (copy_from_user(&setup, arg, size))
430 return -EFAULT;
431
432 if (setup.code > ABS_MAX)
433 return -ERANGE;
434
435 dev = udev->dev;
436
437 error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
438 if (error)
439 return error;
440
441 input_alloc_absinfo(dev);
442 if (!dev->absinfo)
443 return -ENOMEM;
444
445 set_bit(setup.code, dev->absbit);
446 dev->absinfo[setup.code] = setup.absinfo;
447 return 0;
448}
449
450/* legacy setup via write() */
451static int uinput_setup_device_legacy(struct uinput_device *udev,
452 const char __user *buffer, size_t count)
453{
454 struct uinput_user_dev *user_dev;
455 struct input_dev *dev;
456 int i;
457 int retval;
458
459 if (count != sizeof(struct uinput_user_dev))
460 return -EINVAL;
461
462 if (!udev->dev) {
463 retval = uinput_allocate_device(udev);
464 if (retval)
465 return retval;
466 }
467
468 dev = udev->dev;
469
470 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
471 if (IS_ERR(user_dev))
472 return PTR_ERR(user_dev);
473
474 udev->ff_effects_max = user_dev->ff_effects_max;
475
476 /* Ensure name is filled in */
477 if (!user_dev->name[0]) {
478 retval = -EINVAL;
479 goto exit;
480 }
481
482 kfree(dev->name);
483 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
484 GFP_KERNEL);
485 if (!dev->name) {
486 retval = -ENOMEM;
487 goto exit;
488 }
489
490 dev->id.bustype = user_dev->id.bustype;
491 dev->id.vendor = user_dev->id.vendor;
492 dev->id.product = user_dev->id.product;
493 dev->id.version = user_dev->id.version;
494
495 for (i = 0; i < ABS_CNT; i++) {
496 input_abs_set_max(dev, i, user_dev->absmax[i]);
497 input_abs_set_min(dev, i, user_dev->absmin[i]);
498 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
499 input_abs_set_flat(dev, i, user_dev->absflat[i]);
500 }
501
502 retval = uinput_validate_absbits(dev);
503 if (retval < 0)
504 goto exit;
505
506 udev->state = UIST_SETUP_COMPLETE;
507 retval = count;
508
509 exit:
510 kfree(user_dev);
511 return retval;
512}
513
514static ssize_t uinput_inject_events(struct uinput_device *udev,
515 const char __user *buffer, size_t count)
516{
517 struct input_event ev;
518 size_t bytes = 0;
519
520 if (count != 0 && count < input_event_size())
521 return -EINVAL;
522
523 while (bytes + input_event_size() <= count) {
524 /*
525 * Note that even if some events were fetched successfully
526 * we are still going to return EFAULT instead of partial
527 * count to let userspace know that it got it's buffers
528 * all wrong.
529 */
530 if (input_event_from_user(buffer + bytes, &ev))
531 return -EFAULT;
532
533 input_event(udev->dev, ev.type, ev.code, ev.value);
534 bytes += input_event_size();
535 }
536
537 return bytes;
538}
539
540static ssize_t uinput_write(struct file *file, const char __user *buffer,
541 size_t count, loff_t *ppos)
542{
543 struct uinput_device *udev = file->private_data;
544 int retval;
545
546 if (count == 0)
547 return 0;
548
549 retval = mutex_lock_interruptible(&udev->mutex);
550 if (retval)
551 return retval;
552
553 retval = udev->state == UIST_CREATED ?
554 uinput_inject_events(udev, buffer, count) :
555 uinput_setup_device_legacy(udev, buffer, count);
556
557 mutex_unlock(&udev->mutex);
558
559 return retval;
560}
561
562static bool uinput_fetch_next_event(struct uinput_device *udev,
563 struct input_event *event)
564{
565 bool have_event;
566
567 spin_lock_irq(&udev->dev->event_lock);
568
569 have_event = udev->head != udev->tail;
570 if (have_event) {
571 *event = udev->buff[udev->tail];
572 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
573 }
574
575 spin_unlock_irq(&udev->dev->event_lock);
576
577 return have_event;
578}
579
580static ssize_t uinput_events_to_user(struct uinput_device *udev,
581 char __user *buffer, size_t count)
582{
583 struct input_event event;
584 size_t read = 0;
585
586 while (read + input_event_size() <= count &&
587 uinput_fetch_next_event(udev, &event)) {
588
589 if (input_event_to_user(buffer + read, &event))
590 return -EFAULT;
591
592 read += input_event_size();
593 }
594
595 return read;
596}
597
598static ssize_t uinput_read(struct file *file, char __user *buffer,
599 size_t count, loff_t *ppos)
600{
601 struct uinput_device *udev = file->private_data;
602 ssize_t retval;
603
604 if (count != 0 && count < input_event_size())
605 return -EINVAL;
606
607 do {
608 retval = mutex_lock_interruptible(&udev->mutex);
609 if (retval)
610 return retval;
611
612 if (udev->state != UIST_CREATED)
613 retval = -ENODEV;
614 else if (udev->head == udev->tail &&
615 (file->f_flags & O_NONBLOCK))
616 retval = -EAGAIN;
617 else
618 retval = uinput_events_to_user(udev, buffer, count);
619
620 mutex_unlock(&udev->mutex);
621
622 if (retval || count == 0)
623 break;
624
625 if (!(file->f_flags & O_NONBLOCK))
626 retval = wait_event_interruptible(udev->waitq,
627 udev->head != udev->tail ||
628 udev->state != UIST_CREATED);
629 } while (retval == 0);
630
631 return retval;
632}
633
634static unsigned int uinput_poll(struct file *file, poll_table *wait)
635{
636 struct uinput_device *udev = file->private_data;
637
638 poll_wait(file, &udev->waitq, wait);
639
640 if (udev->head != udev->tail)
641 return POLLIN | POLLRDNORM;
642
643 return 0;
644}
645
646static int uinput_release(struct inode *inode, struct file *file)
647{
648 struct uinput_device *udev = file->private_data;
649
650 uinput_destroy_device(udev);
651 kfree(udev);
652
653 return 0;
654}
655
656#ifdef CONFIG_COMPAT
657struct uinput_ff_upload_compat {
658 __u32 request_id;
659 __s32 retval;
660 struct ff_effect_compat effect;
661 struct ff_effect_compat old;
662};
663
664static int uinput_ff_upload_to_user(char __user *buffer,
665 const struct uinput_ff_upload *ff_up)
666{
667 if (in_compat_syscall()) {
668 struct uinput_ff_upload_compat ff_up_compat;
669
670 ff_up_compat.request_id = ff_up->request_id;
671 ff_up_compat.retval = ff_up->retval;
672 /*
673 * It so happens that the pointer that gives us the trouble
674 * is the last field in the structure. Since we don't support
675 * custom waveforms in uinput anyway we can just copy the whole
676 * thing (to the compat size) and ignore the pointer.
677 */
678 memcpy(&ff_up_compat.effect, &ff_up->effect,
679 sizeof(struct ff_effect_compat));
680 memcpy(&ff_up_compat.old, &ff_up->old,
681 sizeof(struct ff_effect_compat));
682
683 if (copy_to_user(buffer, &ff_up_compat,
684 sizeof(struct uinput_ff_upload_compat)))
685 return -EFAULT;
686 } else {
687 if (copy_to_user(buffer, ff_up,
688 sizeof(struct uinput_ff_upload)))
689 return -EFAULT;
690 }
691
692 return 0;
693}
694
695static int uinput_ff_upload_from_user(const char __user *buffer,
696 struct uinput_ff_upload *ff_up)
697{
698 if (in_compat_syscall()) {
699 struct uinput_ff_upload_compat ff_up_compat;
700
701 if (copy_from_user(&ff_up_compat, buffer,
702 sizeof(struct uinput_ff_upload_compat)))
703 return -EFAULT;
704
705 ff_up->request_id = ff_up_compat.request_id;
706 ff_up->retval = ff_up_compat.retval;
707 memcpy(&ff_up->effect, &ff_up_compat.effect,
708 sizeof(struct ff_effect_compat));
709 memcpy(&ff_up->old, &ff_up_compat.old,
710 sizeof(struct ff_effect_compat));
711
712 } else {
713 if (copy_from_user(ff_up, buffer,
714 sizeof(struct uinput_ff_upload)))
715 return -EFAULT;
716 }
717
718 return 0;
719}
720
721#else
722
723static int uinput_ff_upload_to_user(char __user *buffer,
724 const struct uinput_ff_upload *ff_up)
725{
726 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
727 return -EFAULT;
728
729 return 0;
730}
731
732static int uinput_ff_upload_from_user(const char __user *buffer,
733 struct uinput_ff_upload *ff_up)
734{
735 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
736 return -EFAULT;
737
738 return 0;
739}
740
741#endif
742
743#define uinput_set_bit(_arg, _bit, _max) \
744({ \
745 int __ret = 0; \
746 if (udev->state == UIST_CREATED) \
747 __ret = -EINVAL; \
748 else if ((_arg) > (_max)) \
749 __ret = -EINVAL; \
750 else set_bit((_arg), udev->dev->_bit); \
751 __ret; \
752})
753
754static int uinput_str_to_user(void __user *dest, const char *str,
755 unsigned int maxlen)
756{
757 char __user *p = dest;
758 int len, ret;
759
760 if (!str)
761 return -ENOENT;
762
763 if (maxlen == 0)
764 return -EINVAL;
765
766 len = strlen(str) + 1;
767 if (len > maxlen)
768 len = maxlen;
769
770 ret = copy_to_user(p, str, len);
771 if (ret)
772 return -EFAULT;
773
774 /* force terminating '\0' */
775 ret = put_user(0, p + len - 1);
776 return ret ? -EFAULT : len;
777}
778
779static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
780 unsigned long arg, void __user *p)
781{
782 int retval;
783 struct uinput_device *udev = file->private_data;
784 struct uinput_ff_upload ff_up;
785 struct uinput_ff_erase ff_erase;
786 struct uinput_request *req;
787 char *phys;
788 const char *name;
789 unsigned int size;
790
791 retval = mutex_lock_interruptible(&udev->mutex);
792 if (retval)
793 return retval;
794
795 if (!udev->dev) {
796 retval = uinput_allocate_device(udev);
797 if (retval)
798 goto out;
799 }
800
801 switch (cmd) {
802 case UI_GET_VERSION:
803 if (put_user(UINPUT_VERSION,
804 (unsigned int __user *)p))
805 retval = -EFAULT;
806 goto out;
807
808 case UI_DEV_CREATE:
809 retval = uinput_create_device(udev);
810 goto out;
811
812 case UI_DEV_DESTROY:
813 uinput_destroy_device(udev);
814 goto out;
815
816 case UI_DEV_SETUP:
817 retval = uinput_dev_setup(udev, p);
818 goto out;
819
820 /* UI_ABS_SETUP is handled in the variable size ioctls */
821
822 case UI_SET_EVBIT:
823 retval = uinput_set_bit(arg, evbit, EV_MAX);
824 goto out;
825
826 case UI_SET_KEYBIT:
827 retval = uinput_set_bit(arg, keybit, KEY_MAX);
828 goto out;
829
830 case UI_SET_RELBIT:
831 retval = uinput_set_bit(arg, relbit, REL_MAX);
832 goto out;
833
834 case UI_SET_ABSBIT:
835 retval = uinput_set_bit(arg, absbit, ABS_MAX);
836 goto out;
837
838 case UI_SET_MSCBIT:
839 retval = uinput_set_bit(arg, mscbit, MSC_MAX);
840 goto out;
841
842 case UI_SET_LEDBIT:
843 retval = uinput_set_bit(arg, ledbit, LED_MAX);
844 goto out;
845
846 case UI_SET_SNDBIT:
847 retval = uinput_set_bit(arg, sndbit, SND_MAX);
848 goto out;
849
850 case UI_SET_FFBIT:
851 retval = uinput_set_bit(arg, ffbit, FF_MAX);
852 goto out;
853
854 case UI_SET_SWBIT:
855 retval = uinput_set_bit(arg, swbit, SW_MAX);
856 goto out;
857
858 case UI_SET_PROPBIT:
859 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
860 goto out;
861
862 case UI_SET_PHYS:
863 if (udev->state == UIST_CREATED) {
864 retval = -EINVAL;
865 goto out;
866 }
867
868 phys = strndup_user(p, 1024);
869 if (IS_ERR(phys)) {
870 retval = PTR_ERR(phys);
871 goto out;
872 }
873
874 kfree(udev->dev->phys);
875 udev->dev->phys = phys;
876 goto out;
877
878 case UI_BEGIN_FF_UPLOAD:
879 retval = uinput_ff_upload_from_user(p, &ff_up);
880 if (retval)
881 goto out;
882
883 req = uinput_request_find(udev, ff_up.request_id);
884 if (!req || req->code != UI_FF_UPLOAD ||
885 !req->u.upload.effect) {
886 retval = -EINVAL;
887 goto out;
888 }
889
890 ff_up.retval = 0;
891 ff_up.effect = *req->u.upload.effect;
892 if (req->u.upload.old)
893 ff_up.old = *req->u.upload.old;
894 else
895 memset(&ff_up.old, 0, sizeof(struct ff_effect));
896
897 retval = uinput_ff_upload_to_user(p, &ff_up);
898 goto out;
899
900 case UI_BEGIN_FF_ERASE:
901 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
902 retval = -EFAULT;
903 goto out;
904 }
905
906 req = uinput_request_find(udev, ff_erase.request_id);
907 if (!req || req->code != UI_FF_ERASE) {
908 retval = -EINVAL;
909 goto out;
910 }
911
912 ff_erase.retval = 0;
913 ff_erase.effect_id = req->u.effect_id;
914 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
915 retval = -EFAULT;
916 goto out;
917 }
918
919 goto out;
920
921 case UI_END_FF_UPLOAD:
922 retval = uinput_ff_upload_from_user(p, &ff_up);
923 if (retval)
924 goto out;
925
926 req = uinput_request_find(udev, ff_up.request_id);
927 if (!req || req->code != UI_FF_UPLOAD ||
928 !req->u.upload.effect) {
929 retval = -EINVAL;
930 goto out;
931 }
932
933 req->retval = ff_up.retval;
934 uinput_request_done(udev, req);
935 goto out;
936
937 case UI_END_FF_ERASE:
938 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
939 retval = -EFAULT;
940 goto out;
941 }
942
943 req = uinput_request_find(udev, ff_erase.request_id);
944 if (!req || req->code != UI_FF_ERASE) {
945 retval = -EINVAL;
946 goto out;
947 }
948
949 req->retval = ff_erase.retval;
950 uinput_request_done(udev, req);
951 goto out;
952 }
953
954 size = _IOC_SIZE(cmd);
955
956 /* Now check variable-length commands */
957 switch (cmd & ~IOCSIZE_MASK) {
958 case UI_GET_SYSNAME(0):
959 if (udev->state != UIST_CREATED) {
960 retval = -ENOENT;
961 goto out;
962 }
963 name = dev_name(&udev->dev->dev);
964 retval = uinput_str_to_user(p, name, size);
965 goto out;
966
967 case UI_ABS_SETUP & ~IOCSIZE_MASK:
968 retval = uinput_abs_setup(udev, p, size);
969 goto out;
970 }
971
972 retval = -EINVAL;
973 out:
974 mutex_unlock(&udev->mutex);
975 return retval;
976}
977
978static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
979{
980 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
981}
982
983#ifdef CONFIG_COMPAT
984static long uinput_compat_ioctl(struct file *file,
985 unsigned int cmd, unsigned long arg)
986{
987 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
988}
989#endif
990
991static const struct file_operations uinput_fops = {
992 .owner = THIS_MODULE,
993 .open = uinput_open,
994 .release = uinput_release,
995 .read = uinput_read,
996 .write = uinput_write,
997 .poll = uinput_poll,
998 .unlocked_ioctl = uinput_ioctl,
999#ifdef CONFIG_COMPAT
1000 .compat_ioctl = uinput_compat_ioctl,
1001#endif
1002 .llseek = no_llseek,
1003};
1004
1005static struct miscdevice uinput_misc = {
1006 .fops = &uinput_fops,
1007 .minor = UINPUT_MINOR,
1008 .name = UINPUT_NAME,
1009};
1010MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1011MODULE_ALIAS("devname:" UINPUT_NAME);
1012
1013static int __init uinput_init(void)
1014{
1015 return misc_register(&uinput_misc);
1016}
1017
1018static void __exit uinput_exit(void)
1019{
1020 misc_deregister(&uinput_misc);
1021}
1022
1023MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1024MODULE_DESCRIPTION("User level driver support for input subsystem");
1025MODULE_LICENSE("GPL");
1026MODULE_VERSION("0.3");
1027
1028module_init(uinput_init);
1029module_exit(uinput_exit);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * User level driver support for input subsystem
4 *
5 * Heavily based on evdev.c by Vojtech Pavlik
6 *
7 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
8 *
9 * Changes/Revisions:
10 * 0.4 01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
11 * - add UI_GET_SYSNAME ioctl
12 * 0.3 09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
13 * - updated ff support for the changes in kernel interface
14 * - added MODULE_VERSION
15 * 0.2 16/10/2004 (Micah Dowty <micah@navi.cx>)
16 * - added force feedback support
17 * - added UI_SET_PHYS
18 * 0.1 20/06/2002
19 * - first public version
20 */
21#include <uapi/linux/uinput.h>
22#include <linux/poll.h>
23#include <linux/sched.h>
24#include <linux/slab.h>
25#include <linux/module.h>
26#include <linux/init.h>
27#include <linux/fs.h>
28#include <linux/miscdevice.h>
29#include <linux/overflow.h>
30#include <linux/input/mt.h>
31#include "../input-compat.h"
32
33#define UINPUT_NAME "uinput"
34#define UINPUT_BUFFER_SIZE 16
35#define UINPUT_NUM_REQUESTS 16
36
37enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED };
38
39struct uinput_request {
40 unsigned int id;
41 unsigned int code; /* UI_FF_UPLOAD, UI_FF_ERASE */
42
43 int retval;
44 struct completion done;
45
46 union {
47 unsigned int effect_id;
48 struct {
49 struct ff_effect *effect;
50 struct ff_effect *old;
51 } upload;
52 } u;
53};
54
55struct uinput_device {
56 struct input_dev *dev;
57 struct mutex mutex;
58 enum uinput_state state;
59 wait_queue_head_t waitq;
60 unsigned char ready;
61 unsigned char head;
62 unsigned char tail;
63 struct input_event buff[UINPUT_BUFFER_SIZE];
64 unsigned int ff_effects_max;
65
66 struct uinput_request *requests[UINPUT_NUM_REQUESTS];
67 wait_queue_head_t requests_waitq;
68 spinlock_t requests_lock;
69};
70
71static int uinput_dev_event(struct input_dev *dev,
72 unsigned int type, unsigned int code, int value)
73{
74 struct uinput_device *udev = input_get_drvdata(dev);
75 struct timespec64 ts;
76
77 udev->buff[udev->head].type = type;
78 udev->buff[udev->head].code = code;
79 udev->buff[udev->head].value = value;
80 ktime_get_ts64(&ts);
81 udev->buff[udev->head].input_event_sec = ts.tv_sec;
82 udev->buff[udev->head].input_event_usec = ts.tv_nsec / NSEC_PER_USEC;
83 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
84
85 wake_up_interruptible(&udev->waitq);
86
87 return 0;
88}
89
90/* Atomically allocate an ID for the given request. Returns 0 on success. */
91static bool uinput_request_alloc_id(struct uinput_device *udev,
92 struct uinput_request *request)
93{
94 unsigned int id;
95 bool reserved = false;
96
97 spin_lock(&udev->requests_lock);
98
99 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
100 if (!udev->requests[id]) {
101 request->id = id;
102 udev->requests[id] = request;
103 reserved = true;
104 break;
105 }
106 }
107
108 spin_unlock(&udev->requests_lock);
109 return reserved;
110}
111
112static struct uinput_request *uinput_request_find(struct uinput_device *udev,
113 unsigned int id)
114{
115 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
116 if (id >= UINPUT_NUM_REQUESTS)
117 return NULL;
118
119 return udev->requests[id];
120}
121
122static int uinput_request_reserve_slot(struct uinput_device *udev,
123 struct uinput_request *request)
124{
125 /* Allocate slot. If none are available right away, wait. */
126 return wait_event_interruptible(udev->requests_waitq,
127 uinput_request_alloc_id(udev, request));
128}
129
130static void uinput_request_release_slot(struct uinput_device *udev,
131 unsigned int id)
132{
133 /* Mark slot as available */
134 spin_lock(&udev->requests_lock);
135 udev->requests[id] = NULL;
136 spin_unlock(&udev->requests_lock);
137
138 wake_up(&udev->requests_waitq);
139}
140
141static int uinput_request_send(struct uinput_device *udev,
142 struct uinput_request *request)
143{
144 int retval;
145
146 retval = mutex_lock_interruptible(&udev->mutex);
147 if (retval)
148 return retval;
149
150 if (udev->state != UIST_CREATED) {
151 retval = -ENODEV;
152 goto out;
153 }
154
155 init_completion(&request->done);
156
157 /*
158 * Tell our userspace application about this new request
159 * by queueing an input event.
160 */
161 uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
162
163 out:
164 mutex_unlock(&udev->mutex);
165 return retval;
166}
167
168static int uinput_request_submit(struct uinput_device *udev,
169 struct uinput_request *request)
170{
171 int retval;
172
173 retval = uinput_request_reserve_slot(udev, request);
174 if (retval)
175 return retval;
176
177 retval = uinput_request_send(udev, request);
178 if (retval)
179 goto out;
180
181 if (!wait_for_completion_timeout(&request->done, 30 * HZ)) {
182 retval = -ETIMEDOUT;
183 goto out;
184 }
185
186 retval = request->retval;
187
188 out:
189 uinput_request_release_slot(udev, request->id);
190 return retval;
191}
192
193/*
194 * Fail all outstanding requests so handlers don't wait for the userspace
195 * to finish processing them.
196 */
197static void uinput_flush_requests(struct uinput_device *udev)
198{
199 struct uinput_request *request;
200 int i;
201
202 spin_lock(&udev->requests_lock);
203
204 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
205 request = udev->requests[i];
206 if (request) {
207 request->retval = -ENODEV;
208 complete(&request->done);
209 }
210 }
211
212 spin_unlock(&udev->requests_lock);
213}
214
215static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
216{
217 uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
218}
219
220static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
221{
222 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
223}
224
225static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
226{
227 return uinput_dev_event(dev, EV_FF, effect_id, value);
228}
229
230static int uinput_dev_upload_effect(struct input_dev *dev,
231 struct ff_effect *effect,
232 struct ff_effect *old)
233{
234 struct uinput_device *udev = input_get_drvdata(dev);
235 struct uinput_request request;
236
237 /*
238 * uinput driver does not currently support periodic effects with
239 * custom waveform since it does not have a way to pass buffer of
240 * samples (custom_data) to userspace. If ever there is a device
241 * supporting custom waveforms we would need to define an additional
242 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
243 */
244 if (effect->type == FF_PERIODIC &&
245 effect->u.periodic.waveform == FF_CUSTOM)
246 return -EINVAL;
247
248 request.code = UI_FF_UPLOAD;
249 request.u.upload.effect = effect;
250 request.u.upload.old = old;
251
252 return uinput_request_submit(udev, &request);
253}
254
255static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
256{
257 struct uinput_device *udev = input_get_drvdata(dev);
258 struct uinput_request request;
259
260 if (!test_bit(EV_FF, dev->evbit))
261 return -ENOSYS;
262
263 request.code = UI_FF_ERASE;
264 request.u.effect_id = effect_id;
265
266 return uinput_request_submit(udev, &request);
267}
268
269static int uinput_dev_flush(struct input_dev *dev, struct file *file)
270{
271 /*
272 * If we are called with file == NULL that means we are tearing
273 * down the device, and therefore we can not handle FF erase
274 * requests: either we are handling UI_DEV_DESTROY (and holding
275 * the udev->mutex), or the file descriptor is closed and there is
276 * nobody on the other side anymore.
277 */
278 return file ? input_ff_flush(dev, file) : 0;
279}
280
281static void uinput_destroy_device(struct uinput_device *udev)
282{
283 const char *name, *phys;
284 struct input_dev *dev = udev->dev;
285 enum uinput_state old_state = udev->state;
286
287 udev->state = UIST_NEW_DEVICE;
288
289 if (dev) {
290 name = dev->name;
291 phys = dev->phys;
292 if (old_state == UIST_CREATED) {
293 uinput_flush_requests(udev);
294 input_unregister_device(dev);
295 } else {
296 input_free_device(dev);
297 }
298 kfree(name);
299 kfree(phys);
300 udev->dev = NULL;
301 }
302}
303
304static int uinput_create_device(struct uinput_device *udev)
305{
306 struct input_dev *dev = udev->dev;
307 int error, nslot;
308
309 if (udev->state != UIST_SETUP_COMPLETE) {
310 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
311 return -EINVAL;
312 }
313
314 if (test_bit(EV_ABS, dev->evbit)) {
315 input_alloc_absinfo(dev);
316 if (!dev->absinfo) {
317 error = -EINVAL;
318 goto fail1;
319 }
320
321 if (test_bit(ABS_MT_SLOT, dev->absbit)) {
322 nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
323 error = input_mt_init_slots(dev, nslot, 0);
324 if (error)
325 goto fail1;
326 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
327 input_set_events_per_packet(dev, 60);
328 }
329 }
330
331 if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
332 printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
333 UINPUT_NAME);
334 error = -EINVAL;
335 goto fail1;
336 }
337
338 if (udev->ff_effects_max) {
339 error = input_ff_create(dev, udev->ff_effects_max);
340 if (error)
341 goto fail1;
342
343 dev->ff->upload = uinput_dev_upload_effect;
344 dev->ff->erase = uinput_dev_erase_effect;
345 dev->ff->playback = uinput_dev_playback;
346 dev->ff->set_gain = uinput_dev_set_gain;
347 dev->ff->set_autocenter = uinput_dev_set_autocenter;
348 /*
349 * The standard input_ff_flush() implementation does
350 * not quite work for uinput as we can't reasonably
351 * handle FF requests during device teardown.
352 */
353 dev->flush = uinput_dev_flush;
354 }
355
356 dev->event = uinput_dev_event;
357
358 input_set_drvdata(udev->dev, udev);
359
360 error = input_register_device(udev->dev);
361 if (error)
362 goto fail2;
363
364 udev->state = UIST_CREATED;
365
366 return 0;
367
368 fail2: input_ff_destroy(dev);
369 fail1: uinput_destroy_device(udev);
370 return error;
371}
372
373static int uinput_open(struct inode *inode, struct file *file)
374{
375 struct uinput_device *newdev;
376
377 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
378 if (!newdev)
379 return -ENOMEM;
380
381 mutex_init(&newdev->mutex);
382 spin_lock_init(&newdev->requests_lock);
383 init_waitqueue_head(&newdev->requests_waitq);
384 init_waitqueue_head(&newdev->waitq);
385 newdev->state = UIST_NEW_DEVICE;
386
387 file->private_data = newdev;
388 stream_open(inode, file);
389
390 return 0;
391}
392
393static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
394 const struct input_absinfo *abs)
395{
396 int min, max, range;
397
398 min = abs->minimum;
399 max = abs->maximum;
400
401 if ((min != 0 || max != 0) && max < min) {
402 printk(KERN_DEBUG
403 "%s: invalid abs[%02x] min:%d max:%d\n",
404 UINPUT_NAME, code, min, max);
405 return -EINVAL;
406 }
407
408 if (!check_sub_overflow(max, min, &range) && abs->flat > range) {
409 printk(KERN_DEBUG
410 "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
411 UINPUT_NAME, code, abs->flat, min, max);
412 return -EINVAL;
413 }
414
415 return 0;
416}
417
418static int uinput_validate_absbits(struct input_dev *dev)
419{
420 unsigned int cnt;
421 int error;
422
423 if (!test_bit(EV_ABS, dev->evbit))
424 return 0;
425
426 /*
427 * Check if absmin/absmax/absfuzz/absflat are sane.
428 */
429
430 for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
431 if (!dev->absinfo)
432 return -EINVAL;
433
434 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
435 if (error)
436 return error;
437 }
438
439 return 0;
440}
441
442static int uinput_dev_setup(struct uinput_device *udev,
443 struct uinput_setup __user *arg)
444{
445 struct uinput_setup setup;
446 struct input_dev *dev;
447
448 if (udev->state == UIST_CREATED)
449 return -EINVAL;
450
451 if (copy_from_user(&setup, arg, sizeof(setup)))
452 return -EFAULT;
453
454 if (!setup.name[0])
455 return -EINVAL;
456
457 dev = udev->dev;
458 dev->id = setup.id;
459 udev->ff_effects_max = setup.ff_effects_max;
460
461 kfree(dev->name);
462 dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
463 if (!dev->name)
464 return -ENOMEM;
465
466 udev->state = UIST_SETUP_COMPLETE;
467 return 0;
468}
469
470static int uinput_abs_setup(struct uinput_device *udev,
471 struct uinput_setup __user *arg, size_t size)
472{
473 struct uinput_abs_setup setup = {};
474 struct input_dev *dev;
475 int error;
476
477 if (size > sizeof(setup))
478 return -E2BIG;
479
480 if (udev->state == UIST_CREATED)
481 return -EINVAL;
482
483 if (copy_from_user(&setup, arg, size))
484 return -EFAULT;
485
486 if (setup.code > ABS_MAX)
487 return -ERANGE;
488
489 dev = udev->dev;
490
491 error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
492 if (error)
493 return error;
494
495 input_alloc_absinfo(dev);
496 if (!dev->absinfo)
497 return -ENOMEM;
498
499 set_bit(setup.code, dev->absbit);
500 dev->absinfo[setup.code] = setup.absinfo;
501 return 0;
502}
503
504/* legacy setup via write() */
505static int uinput_setup_device_legacy(struct uinput_device *udev,
506 const char __user *buffer, size_t count)
507{
508 struct uinput_user_dev *user_dev;
509 struct input_dev *dev;
510 int i;
511 int retval;
512
513 if (count != sizeof(struct uinput_user_dev))
514 return -EINVAL;
515
516 if (!udev->dev) {
517 udev->dev = input_allocate_device();
518 if (!udev->dev)
519 return -ENOMEM;
520 }
521
522 dev = udev->dev;
523
524 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
525 if (IS_ERR(user_dev))
526 return PTR_ERR(user_dev);
527
528 udev->ff_effects_max = user_dev->ff_effects_max;
529
530 /* Ensure name is filled in */
531 if (!user_dev->name[0]) {
532 retval = -EINVAL;
533 goto exit;
534 }
535
536 kfree(dev->name);
537 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
538 GFP_KERNEL);
539 if (!dev->name) {
540 retval = -ENOMEM;
541 goto exit;
542 }
543
544 dev->id.bustype = user_dev->id.bustype;
545 dev->id.vendor = user_dev->id.vendor;
546 dev->id.product = user_dev->id.product;
547 dev->id.version = user_dev->id.version;
548
549 for (i = 0; i < ABS_CNT; i++) {
550 input_abs_set_max(dev, i, user_dev->absmax[i]);
551 input_abs_set_min(dev, i, user_dev->absmin[i]);
552 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
553 input_abs_set_flat(dev, i, user_dev->absflat[i]);
554 }
555
556 retval = uinput_validate_absbits(dev);
557 if (retval < 0)
558 goto exit;
559
560 udev->state = UIST_SETUP_COMPLETE;
561 retval = count;
562
563 exit:
564 kfree(user_dev);
565 return retval;
566}
567
568static ssize_t uinput_inject_events(struct uinput_device *udev,
569 const char __user *buffer, size_t count)
570{
571 struct input_event ev;
572 size_t bytes = 0;
573
574 if (count != 0 && count < input_event_size())
575 return -EINVAL;
576
577 while (bytes + input_event_size() <= count) {
578 /*
579 * Note that even if some events were fetched successfully
580 * we are still going to return EFAULT instead of partial
581 * count to let userspace know that it got it's buffers
582 * all wrong.
583 */
584 if (input_event_from_user(buffer + bytes, &ev))
585 return -EFAULT;
586
587 input_event(udev->dev, ev.type, ev.code, ev.value);
588 bytes += input_event_size();
589 cond_resched();
590 }
591
592 return bytes;
593}
594
595static ssize_t uinput_write(struct file *file, const char __user *buffer,
596 size_t count, loff_t *ppos)
597{
598 struct uinput_device *udev = file->private_data;
599 int retval;
600
601 if (count == 0)
602 return 0;
603
604 retval = mutex_lock_interruptible(&udev->mutex);
605 if (retval)
606 return retval;
607
608 retval = udev->state == UIST_CREATED ?
609 uinput_inject_events(udev, buffer, count) :
610 uinput_setup_device_legacy(udev, buffer, count);
611
612 mutex_unlock(&udev->mutex);
613
614 return retval;
615}
616
617static bool uinput_fetch_next_event(struct uinput_device *udev,
618 struct input_event *event)
619{
620 bool have_event;
621
622 spin_lock_irq(&udev->dev->event_lock);
623
624 have_event = udev->head != udev->tail;
625 if (have_event) {
626 *event = udev->buff[udev->tail];
627 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
628 }
629
630 spin_unlock_irq(&udev->dev->event_lock);
631
632 return have_event;
633}
634
635static ssize_t uinput_events_to_user(struct uinput_device *udev,
636 char __user *buffer, size_t count)
637{
638 struct input_event event;
639 size_t read = 0;
640
641 while (read + input_event_size() <= count &&
642 uinput_fetch_next_event(udev, &event)) {
643
644 if (input_event_to_user(buffer + read, &event))
645 return -EFAULT;
646
647 read += input_event_size();
648 }
649
650 return read;
651}
652
653static ssize_t uinput_read(struct file *file, char __user *buffer,
654 size_t count, loff_t *ppos)
655{
656 struct uinput_device *udev = file->private_data;
657 ssize_t retval;
658
659 if (count != 0 && count < input_event_size())
660 return -EINVAL;
661
662 do {
663 retval = mutex_lock_interruptible(&udev->mutex);
664 if (retval)
665 return retval;
666
667 if (udev->state != UIST_CREATED)
668 retval = -ENODEV;
669 else if (udev->head == udev->tail &&
670 (file->f_flags & O_NONBLOCK))
671 retval = -EAGAIN;
672 else
673 retval = uinput_events_to_user(udev, buffer, count);
674
675 mutex_unlock(&udev->mutex);
676
677 if (retval || count == 0)
678 break;
679
680 if (!(file->f_flags & O_NONBLOCK))
681 retval = wait_event_interruptible(udev->waitq,
682 udev->head != udev->tail ||
683 udev->state != UIST_CREATED);
684 } while (retval == 0);
685
686 return retval;
687}
688
689static __poll_t uinput_poll(struct file *file, poll_table *wait)
690{
691 struct uinput_device *udev = file->private_data;
692
693 poll_wait(file, &udev->waitq, wait);
694
695 if (udev->head != udev->tail)
696 return EPOLLIN | EPOLLRDNORM;
697
698 return 0;
699}
700
701static int uinput_release(struct inode *inode, struct file *file)
702{
703 struct uinput_device *udev = file->private_data;
704
705 uinput_destroy_device(udev);
706 kfree(udev);
707
708 return 0;
709}
710
711#ifdef CONFIG_COMPAT
712struct uinput_ff_upload_compat {
713 __u32 request_id;
714 __s32 retval;
715 struct ff_effect_compat effect;
716 struct ff_effect_compat old;
717};
718
719static int uinput_ff_upload_to_user(char __user *buffer,
720 const struct uinput_ff_upload *ff_up)
721{
722 if (in_compat_syscall()) {
723 struct uinput_ff_upload_compat ff_up_compat;
724
725 ff_up_compat.request_id = ff_up->request_id;
726 ff_up_compat.retval = ff_up->retval;
727 /*
728 * It so happens that the pointer that gives us the trouble
729 * is the last field in the structure. Since we don't support
730 * custom waveforms in uinput anyway we can just copy the whole
731 * thing (to the compat size) and ignore the pointer.
732 */
733 memcpy(&ff_up_compat.effect, &ff_up->effect,
734 sizeof(struct ff_effect_compat));
735 memcpy(&ff_up_compat.old, &ff_up->old,
736 sizeof(struct ff_effect_compat));
737
738 if (copy_to_user(buffer, &ff_up_compat,
739 sizeof(struct uinput_ff_upload_compat)))
740 return -EFAULT;
741 } else {
742 if (copy_to_user(buffer, ff_up,
743 sizeof(struct uinput_ff_upload)))
744 return -EFAULT;
745 }
746
747 return 0;
748}
749
750static int uinput_ff_upload_from_user(const char __user *buffer,
751 struct uinput_ff_upload *ff_up)
752{
753 if (in_compat_syscall()) {
754 struct uinput_ff_upload_compat ff_up_compat;
755
756 if (copy_from_user(&ff_up_compat, buffer,
757 sizeof(struct uinput_ff_upload_compat)))
758 return -EFAULT;
759
760 ff_up->request_id = ff_up_compat.request_id;
761 ff_up->retval = ff_up_compat.retval;
762 memcpy(&ff_up->effect, &ff_up_compat.effect,
763 sizeof(struct ff_effect_compat));
764 memcpy(&ff_up->old, &ff_up_compat.old,
765 sizeof(struct ff_effect_compat));
766
767 } else {
768 if (copy_from_user(ff_up, buffer,
769 sizeof(struct uinput_ff_upload)))
770 return -EFAULT;
771 }
772
773 return 0;
774}
775
776#else
777
778static int uinput_ff_upload_to_user(char __user *buffer,
779 const struct uinput_ff_upload *ff_up)
780{
781 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
782 return -EFAULT;
783
784 return 0;
785}
786
787static int uinput_ff_upload_from_user(const char __user *buffer,
788 struct uinput_ff_upload *ff_up)
789{
790 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
791 return -EFAULT;
792
793 return 0;
794}
795
796#endif
797
798#define uinput_set_bit(_arg, _bit, _max) \
799({ \
800 int __ret = 0; \
801 if (udev->state == UIST_CREATED) \
802 __ret = -EINVAL; \
803 else if ((_arg) > (_max)) \
804 __ret = -EINVAL; \
805 else set_bit((_arg), udev->dev->_bit); \
806 __ret; \
807})
808
809static int uinput_str_to_user(void __user *dest, const char *str,
810 unsigned int maxlen)
811{
812 char __user *p = dest;
813 int len, ret;
814
815 if (!str)
816 return -ENOENT;
817
818 if (maxlen == 0)
819 return -EINVAL;
820
821 len = strlen(str) + 1;
822 if (len > maxlen)
823 len = maxlen;
824
825 ret = copy_to_user(p, str, len);
826 if (ret)
827 return -EFAULT;
828
829 /* force terminating '\0' */
830 ret = put_user(0, p + len - 1);
831 return ret ? -EFAULT : len;
832}
833
834static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
835 unsigned long arg, void __user *p)
836{
837 int retval;
838 struct uinput_device *udev = file->private_data;
839 struct uinput_ff_upload ff_up;
840 struct uinput_ff_erase ff_erase;
841 struct uinput_request *req;
842 char *phys;
843 const char *name;
844 unsigned int size;
845
846 retval = mutex_lock_interruptible(&udev->mutex);
847 if (retval)
848 return retval;
849
850 if (!udev->dev) {
851 udev->dev = input_allocate_device();
852 if (!udev->dev) {
853 retval = -ENOMEM;
854 goto out;
855 }
856 }
857
858 switch (cmd) {
859 case UI_GET_VERSION:
860 if (put_user(UINPUT_VERSION, (unsigned int __user *)p))
861 retval = -EFAULT;
862 goto out;
863
864 case UI_DEV_CREATE:
865 retval = uinput_create_device(udev);
866 goto out;
867
868 case UI_DEV_DESTROY:
869 uinput_destroy_device(udev);
870 goto out;
871
872 case UI_DEV_SETUP:
873 retval = uinput_dev_setup(udev, p);
874 goto out;
875
876 /* UI_ABS_SETUP is handled in the variable size ioctls */
877
878 case UI_SET_EVBIT:
879 retval = uinput_set_bit(arg, evbit, EV_MAX);
880 goto out;
881
882 case UI_SET_KEYBIT:
883 retval = uinput_set_bit(arg, keybit, KEY_MAX);
884 goto out;
885
886 case UI_SET_RELBIT:
887 retval = uinput_set_bit(arg, relbit, REL_MAX);
888 goto out;
889
890 case UI_SET_ABSBIT:
891 retval = uinput_set_bit(arg, absbit, ABS_MAX);
892 goto out;
893
894 case UI_SET_MSCBIT:
895 retval = uinput_set_bit(arg, mscbit, MSC_MAX);
896 goto out;
897
898 case UI_SET_LEDBIT:
899 retval = uinput_set_bit(arg, ledbit, LED_MAX);
900 goto out;
901
902 case UI_SET_SNDBIT:
903 retval = uinput_set_bit(arg, sndbit, SND_MAX);
904 goto out;
905
906 case UI_SET_FFBIT:
907 retval = uinput_set_bit(arg, ffbit, FF_MAX);
908 goto out;
909
910 case UI_SET_SWBIT:
911 retval = uinput_set_bit(arg, swbit, SW_MAX);
912 goto out;
913
914 case UI_SET_PROPBIT:
915 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
916 goto out;
917
918 case UI_SET_PHYS:
919 if (udev->state == UIST_CREATED) {
920 retval = -EINVAL;
921 goto out;
922 }
923
924 phys = strndup_user(p, 1024);
925 if (IS_ERR(phys)) {
926 retval = PTR_ERR(phys);
927 goto out;
928 }
929
930 kfree(udev->dev->phys);
931 udev->dev->phys = phys;
932 goto out;
933
934 case UI_BEGIN_FF_UPLOAD:
935 retval = uinput_ff_upload_from_user(p, &ff_up);
936 if (retval)
937 goto out;
938
939 req = uinput_request_find(udev, ff_up.request_id);
940 if (!req || req->code != UI_FF_UPLOAD ||
941 !req->u.upload.effect) {
942 retval = -EINVAL;
943 goto out;
944 }
945
946 ff_up.retval = 0;
947 ff_up.effect = *req->u.upload.effect;
948 if (req->u.upload.old)
949 ff_up.old = *req->u.upload.old;
950 else
951 memset(&ff_up.old, 0, sizeof(struct ff_effect));
952
953 retval = uinput_ff_upload_to_user(p, &ff_up);
954 goto out;
955
956 case UI_BEGIN_FF_ERASE:
957 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
958 retval = -EFAULT;
959 goto out;
960 }
961
962 req = uinput_request_find(udev, ff_erase.request_id);
963 if (!req || req->code != UI_FF_ERASE) {
964 retval = -EINVAL;
965 goto out;
966 }
967
968 ff_erase.retval = 0;
969 ff_erase.effect_id = req->u.effect_id;
970 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
971 retval = -EFAULT;
972 goto out;
973 }
974
975 goto out;
976
977 case UI_END_FF_UPLOAD:
978 retval = uinput_ff_upload_from_user(p, &ff_up);
979 if (retval)
980 goto out;
981
982 req = uinput_request_find(udev, ff_up.request_id);
983 if (!req || req->code != UI_FF_UPLOAD ||
984 !req->u.upload.effect) {
985 retval = -EINVAL;
986 goto out;
987 }
988
989 req->retval = ff_up.retval;
990 complete(&req->done);
991 goto out;
992
993 case UI_END_FF_ERASE:
994 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
995 retval = -EFAULT;
996 goto out;
997 }
998
999 req = uinput_request_find(udev, ff_erase.request_id);
1000 if (!req || req->code != UI_FF_ERASE) {
1001 retval = -EINVAL;
1002 goto out;
1003 }
1004
1005 req->retval = ff_erase.retval;
1006 complete(&req->done);
1007 goto out;
1008 }
1009
1010 size = _IOC_SIZE(cmd);
1011
1012 /* Now check variable-length commands */
1013 switch (cmd & ~IOCSIZE_MASK) {
1014 case UI_GET_SYSNAME(0):
1015 if (udev->state != UIST_CREATED) {
1016 retval = -ENOENT;
1017 goto out;
1018 }
1019 name = dev_name(&udev->dev->dev);
1020 retval = uinput_str_to_user(p, name, size);
1021 goto out;
1022
1023 case UI_ABS_SETUP & ~IOCSIZE_MASK:
1024 retval = uinput_abs_setup(udev, p, size);
1025 goto out;
1026 }
1027
1028 retval = -EINVAL;
1029 out:
1030 mutex_unlock(&udev->mutex);
1031 return retval;
1032}
1033
1034static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1035{
1036 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
1037}
1038
1039#ifdef CONFIG_COMPAT
1040
1041/*
1042 * These IOCTLs change their size and thus their numbers between
1043 * 32 and 64 bits.
1044 */
1045#define UI_SET_PHYS_COMPAT \
1046 _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t)
1047#define UI_BEGIN_FF_UPLOAD_COMPAT \
1048 _IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload_compat)
1049#define UI_END_FF_UPLOAD_COMPAT \
1050 _IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload_compat)
1051
1052static long uinput_compat_ioctl(struct file *file,
1053 unsigned int cmd, unsigned long arg)
1054{
1055 switch (cmd) {
1056 case UI_SET_PHYS_COMPAT:
1057 cmd = UI_SET_PHYS;
1058 break;
1059 case UI_BEGIN_FF_UPLOAD_COMPAT:
1060 cmd = UI_BEGIN_FF_UPLOAD;
1061 break;
1062 case UI_END_FF_UPLOAD_COMPAT:
1063 cmd = UI_END_FF_UPLOAD;
1064 break;
1065 }
1066
1067 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
1068}
1069#endif
1070
1071static const struct file_operations uinput_fops = {
1072 .owner = THIS_MODULE,
1073 .open = uinput_open,
1074 .release = uinput_release,
1075 .read = uinput_read,
1076 .write = uinput_write,
1077 .poll = uinput_poll,
1078 .unlocked_ioctl = uinput_ioctl,
1079#ifdef CONFIG_COMPAT
1080 .compat_ioctl = uinput_compat_ioctl,
1081#endif
1082 .llseek = no_llseek,
1083};
1084
1085static struct miscdevice uinput_misc = {
1086 .fops = &uinput_fops,
1087 .minor = UINPUT_MINOR,
1088 .name = UINPUT_NAME,
1089};
1090module_misc_device(uinput_misc);
1091
1092MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1093MODULE_ALIAS("devname:" UINPUT_NAME);
1094
1095MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1096MODULE_DESCRIPTION("User level driver support for input subsystem");
1097MODULE_LICENSE("GPL");