Loading...
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#define UINPUT_TIMESTAMP_ALLOWED_OFFSET_SECS 10
37
38enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED };
39
40struct uinput_request {
41 unsigned int id;
42 unsigned int code; /* UI_FF_UPLOAD, UI_FF_ERASE */
43
44 int retval;
45 struct completion done;
46
47 union {
48 unsigned int effect_id;
49 struct {
50 struct ff_effect *effect;
51 struct ff_effect *old;
52 } upload;
53 } u;
54};
55
56struct uinput_device {
57 struct input_dev *dev;
58 struct mutex mutex;
59 enum uinput_state state;
60 wait_queue_head_t waitq;
61 unsigned char ready;
62 unsigned char head;
63 unsigned char tail;
64 struct input_event buff[UINPUT_BUFFER_SIZE];
65 unsigned int ff_effects_max;
66
67 struct uinput_request *requests[UINPUT_NUM_REQUESTS];
68 wait_queue_head_t requests_waitq;
69 spinlock_t requests_lock;
70};
71
72static int uinput_dev_event(struct input_dev *dev,
73 unsigned int type, unsigned int code, int value)
74{
75 struct uinput_device *udev = input_get_drvdata(dev);
76 struct timespec64 ts;
77
78 ktime_get_ts64(&ts);
79
80 udev->buff[udev->head] = (struct input_event) {
81 .input_event_sec = ts.tv_sec,
82 .input_event_usec = ts.tv_nsec / NSEC_PER_USEC,
83 .type = type,
84 .code = code,
85 .value = value,
86 };
87
88 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
89
90 wake_up_interruptible(&udev->waitq);
91
92 return 0;
93}
94
95/* Atomically allocate an ID for the given request. Returns 0 on success. */
96static bool uinput_request_alloc_id(struct uinput_device *udev,
97 struct uinput_request *request)
98{
99 unsigned int id;
100 bool reserved = false;
101
102 spin_lock(&udev->requests_lock);
103
104 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
105 if (!udev->requests[id]) {
106 request->id = id;
107 udev->requests[id] = request;
108 reserved = true;
109 break;
110 }
111 }
112
113 spin_unlock(&udev->requests_lock);
114 return reserved;
115}
116
117static struct uinput_request *uinput_request_find(struct uinput_device *udev,
118 unsigned int id)
119{
120 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
121 if (id >= UINPUT_NUM_REQUESTS)
122 return NULL;
123
124 return udev->requests[id];
125}
126
127static int uinput_request_reserve_slot(struct uinput_device *udev,
128 struct uinput_request *request)
129{
130 /* Allocate slot. If none are available right away, wait. */
131 return wait_event_interruptible(udev->requests_waitq,
132 uinput_request_alloc_id(udev, request));
133}
134
135static void uinput_request_release_slot(struct uinput_device *udev,
136 unsigned int id)
137{
138 /* Mark slot as available */
139 spin_lock(&udev->requests_lock);
140 udev->requests[id] = NULL;
141 spin_unlock(&udev->requests_lock);
142
143 wake_up(&udev->requests_waitq);
144}
145
146static int uinput_request_send(struct uinput_device *udev,
147 struct uinput_request *request)
148{
149 int retval;
150
151 retval = mutex_lock_interruptible(&udev->mutex);
152 if (retval)
153 return retval;
154
155 if (udev->state != UIST_CREATED) {
156 retval = -ENODEV;
157 goto out;
158 }
159
160 init_completion(&request->done);
161
162 /*
163 * Tell our userspace application about this new request
164 * by queueing an input event.
165 */
166 uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
167
168 out:
169 mutex_unlock(&udev->mutex);
170 return retval;
171}
172
173static int uinput_request_submit(struct uinput_device *udev,
174 struct uinput_request *request)
175{
176 int retval;
177
178 retval = uinput_request_reserve_slot(udev, request);
179 if (retval)
180 return retval;
181
182 retval = uinput_request_send(udev, request);
183 if (retval)
184 goto out;
185
186 if (!wait_for_completion_timeout(&request->done, 30 * HZ)) {
187 retval = -ETIMEDOUT;
188 goto out;
189 }
190
191 retval = request->retval;
192
193 out:
194 uinput_request_release_slot(udev, request->id);
195 return retval;
196}
197
198/*
199 * Fail all outstanding requests so handlers don't wait for the userspace
200 * to finish processing them.
201 */
202static void uinput_flush_requests(struct uinput_device *udev)
203{
204 struct uinput_request *request;
205 int i;
206
207 spin_lock(&udev->requests_lock);
208
209 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
210 request = udev->requests[i];
211 if (request) {
212 request->retval = -ENODEV;
213 complete(&request->done);
214 }
215 }
216
217 spin_unlock(&udev->requests_lock);
218}
219
220static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
221{
222 uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
223}
224
225static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
226{
227 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
228}
229
230static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
231{
232 return uinput_dev_event(dev, EV_FF, effect_id, value);
233}
234
235static int uinput_dev_upload_effect(struct input_dev *dev,
236 struct ff_effect *effect,
237 struct ff_effect *old)
238{
239 struct uinput_device *udev = input_get_drvdata(dev);
240 struct uinput_request request;
241
242 /*
243 * uinput driver does not currently support periodic effects with
244 * custom waveform since it does not have a way to pass buffer of
245 * samples (custom_data) to userspace. If ever there is a device
246 * supporting custom waveforms we would need to define an additional
247 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
248 */
249 if (effect->type == FF_PERIODIC &&
250 effect->u.periodic.waveform == FF_CUSTOM)
251 return -EINVAL;
252
253 request.code = UI_FF_UPLOAD;
254 request.u.upload.effect = effect;
255 request.u.upload.old = old;
256
257 return uinput_request_submit(udev, &request);
258}
259
260static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
261{
262 struct uinput_device *udev = input_get_drvdata(dev);
263 struct uinput_request request;
264
265 if (!test_bit(EV_FF, dev->evbit))
266 return -ENOSYS;
267
268 request.code = UI_FF_ERASE;
269 request.u.effect_id = effect_id;
270
271 return uinput_request_submit(udev, &request);
272}
273
274static int uinput_dev_flush(struct input_dev *dev, struct file *file)
275{
276 /*
277 * If we are called with file == NULL that means we are tearing
278 * down the device, and therefore we can not handle FF erase
279 * requests: either we are handling UI_DEV_DESTROY (and holding
280 * the udev->mutex), or the file descriptor is closed and there is
281 * nobody on the other side anymore.
282 */
283 return file ? input_ff_flush(dev, file) : 0;
284}
285
286static void uinput_destroy_device(struct uinput_device *udev)
287{
288 const char *name, *phys;
289 struct input_dev *dev = udev->dev;
290 enum uinput_state old_state = udev->state;
291
292 udev->state = UIST_NEW_DEVICE;
293
294 if (dev) {
295 name = dev->name;
296 phys = dev->phys;
297 if (old_state == UIST_CREATED) {
298 uinput_flush_requests(udev);
299 input_unregister_device(dev);
300 } else {
301 input_free_device(dev);
302 }
303 kfree(name);
304 kfree(phys);
305 udev->dev = NULL;
306 }
307}
308
309static int uinput_create_device(struct uinput_device *udev)
310{
311 struct input_dev *dev = udev->dev;
312 int error, nslot;
313
314 if (udev->state != UIST_SETUP_COMPLETE) {
315 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
316 return -EINVAL;
317 }
318
319 if (test_bit(EV_ABS, dev->evbit)) {
320 input_alloc_absinfo(dev);
321 if (!dev->absinfo) {
322 error = -EINVAL;
323 goto fail1;
324 }
325
326 if (test_bit(ABS_MT_SLOT, dev->absbit)) {
327 nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
328 error = input_mt_init_slots(dev, nslot, 0);
329 if (error)
330 goto fail1;
331 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
332 input_set_events_per_packet(dev, 60);
333 }
334 }
335
336 if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
337 printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
338 UINPUT_NAME);
339 error = -EINVAL;
340 goto fail1;
341 }
342
343 if (udev->ff_effects_max) {
344 error = input_ff_create(dev, udev->ff_effects_max);
345 if (error)
346 goto fail1;
347
348 dev->ff->upload = uinput_dev_upload_effect;
349 dev->ff->erase = uinput_dev_erase_effect;
350 dev->ff->playback = uinput_dev_playback;
351 dev->ff->set_gain = uinput_dev_set_gain;
352 dev->ff->set_autocenter = uinput_dev_set_autocenter;
353 /*
354 * The standard input_ff_flush() implementation does
355 * not quite work for uinput as we can't reasonably
356 * handle FF requests during device teardown.
357 */
358 dev->flush = uinput_dev_flush;
359 }
360
361 dev->event = uinput_dev_event;
362
363 input_set_drvdata(udev->dev, udev);
364
365 error = input_register_device(udev->dev);
366 if (error)
367 goto fail2;
368
369 udev->state = UIST_CREATED;
370
371 return 0;
372
373 fail2: input_ff_destroy(dev);
374 fail1: uinput_destroy_device(udev);
375 return error;
376}
377
378static int uinput_open(struct inode *inode, struct file *file)
379{
380 struct uinput_device *newdev;
381
382 newdev = kzalloc(sizeof(*newdev), GFP_KERNEL);
383 if (!newdev)
384 return -ENOMEM;
385
386 mutex_init(&newdev->mutex);
387 spin_lock_init(&newdev->requests_lock);
388 init_waitqueue_head(&newdev->requests_waitq);
389 init_waitqueue_head(&newdev->waitq);
390 newdev->state = UIST_NEW_DEVICE;
391
392 file->private_data = newdev;
393 stream_open(inode, file);
394
395 return 0;
396}
397
398static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
399 const struct input_absinfo *abs)
400{
401 int min, max, range;
402
403 min = abs->minimum;
404 max = abs->maximum;
405
406 if ((min != 0 || max != 0) && max < min) {
407 printk(KERN_DEBUG
408 "%s: invalid abs[%02x] min:%d max:%d\n",
409 UINPUT_NAME, code, min, max);
410 return -EINVAL;
411 }
412
413 if (!check_sub_overflow(max, min, &range) && abs->flat > range) {
414 printk(KERN_DEBUG
415 "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
416 UINPUT_NAME, code, abs->flat, min, max);
417 return -EINVAL;
418 }
419
420 /*
421 * Limit number of contacts to a reasonable value (100). This
422 * ensures that we need less than 2 pages for struct input_mt
423 * (we are not using in-kernel slot assignment so not going to
424 * allocate memory for the "red" table), and we should have no
425 * trouble getting this much memory.
426 */
427 if (code == ABS_MT_SLOT && max > 99) {
428 printk(KERN_DEBUG
429 "%s: unreasonably large number of slots requested: %d\n",
430 UINPUT_NAME, max);
431 return -EINVAL;
432 }
433
434 return 0;
435}
436
437static int uinput_validate_absbits(struct input_dev *dev)
438{
439 unsigned int cnt;
440 int error;
441
442 if (!test_bit(EV_ABS, dev->evbit))
443 return 0;
444
445 /*
446 * Check if absmin/absmax/absfuzz/absflat are sane.
447 */
448
449 for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
450 if (!dev->absinfo)
451 return -EINVAL;
452
453 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
454 if (error)
455 return error;
456 }
457
458 return 0;
459}
460
461static int uinput_dev_setup(struct uinput_device *udev,
462 struct uinput_setup __user *arg)
463{
464 struct uinput_setup setup;
465 struct input_dev *dev;
466
467 if (udev->state == UIST_CREATED)
468 return -EINVAL;
469
470 if (copy_from_user(&setup, arg, sizeof(setup)))
471 return -EFAULT;
472
473 if (!setup.name[0])
474 return -EINVAL;
475
476 dev = udev->dev;
477 dev->id = setup.id;
478 udev->ff_effects_max = setup.ff_effects_max;
479
480 kfree(dev->name);
481 dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
482 if (!dev->name)
483 return -ENOMEM;
484
485 udev->state = UIST_SETUP_COMPLETE;
486 return 0;
487}
488
489static int uinput_abs_setup(struct uinput_device *udev,
490 struct uinput_setup __user *arg, size_t size)
491{
492 struct uinput_abs_setup setup = {};
493 struct input_dev *dev;
494 int error;
495
496 if (size > sizeof(setup))
497 return -E2BIG;
498
499 if (udev->state == UIST_CREATED)
500 return -EINVAL;
501
502 if (copy_from_user(&setup, arg, size))
503 return -EFAULT;
504
505 if (setup.code > ABS_MAX)
506 return -ERANGE;
507
508 dev = udev->dev;
509
510 error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
511 if (error)
512 return error;
513
514 input_alloc_absinfo(dev);
515 if (!dev->absinfo)
516 return -ENOMEM;
517
518 set_bit(setup.code, dev->absbit);
519 dev->absinfo[setup.code] = setup.absinfo;
520 return 0;
521}
522
523/* legacy setup via write() */
524static int uinput_setup_device_legacy(struct uinput_device *udev,
525 const char __user *buffer, size_t count)
526{
527 struct uinput_user_dev *user_dev;
528 struct input_dev *dev;
529 int i;
530 int retval;
531
532 if (count != sizeof(struct uinput_user_dev))
533 return -EINVAL;
534
535 if (!udev->dev) {
536 udev->dev = input_allocate_device();
537 if (!udev->dev)
538 return -ENOMEM;
539 }
540
541 dev = udev->dev;
542
543 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
544 if (IS_ERR(user_dev))
545 return PTR_ERR(user_dev);
546
547 udev->ff_effects_max = user_dev->ff_effects_max;
548
549 /* Ensure name is filled in */
550 if (!user_dev->name[0]) {
551 retval = -EINVAL;
552 goto exit;
553 }
554
555 kfree(dev->name);
556 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
557 GFP_KERNEL);
558 if (!dev->name) {
559 retval = -ENOMEM;
560 goto exit;
561 }
562
563 dev->id.bustype = user_dev->id.bustype;
564 dev->id.vendor = user_dev->id.vendor;
565 dev->id.product = user_dev->id.product;
566 dev->id.version = user_dev->id.version;
567
568 for (i = 0; i < ABS_CNT; i++) {
569 input_abs_set_max(dev, i, user_dev->absmax[i]);
570 input_abs_set_min(dev, i, user_dev->absmin[i]);
571 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
572 input_abs_set_flat(dev, i, user_dev->absflat[i]);
573 }
574
575 retval = uinput_validate_absbits(dev);
576 if (retval < 0)
577 goto exit;
578
579 udev->state = UIST_SETUP_COMPLETE;
580 retval = count;
581
582 exit:
583 kfree(user_dev);
584 return retval;
585}
586
587/*
588 * Returns true if the given timestamp is valid (i.e., if all the following
589 * conditions are satisfied), false otherwise.
590 * 1) given timestamp is positive
591 * 2) it's within the allowed offset before the current time
592 * 3) it's not in the future
593 */
594static bool is_valid_timestamp(const ktime_t timestamp)
595{
596 ktime_t zero_time;
597 ktime_t current_time;
598 ktime_t min_time;
599 ktime_t offset;
600
601 zero_time = ktime_set(0, 0);
602 if (ktime_compare(zero_time, timestamp) >= 0)
603 return false;
604
605 current_time = ktime_get();
606 offset = ktime_set(UINPUT_TIMESTAMP_ALLOWED_OFFSET_SECS, 0);
607 min_time = ktime_sub(current_time, offset);
608
609 if (ktime_after(min_time, timestamp) || ktime_after(timestamp, current_time))
610 return false;
611
612 return true;
613}
614
615static ssize_t uinput_inject_events(struct uinput_device *udev,
616 const char __user *buffer, size_t count)
617{
618 struct input_event ev;
619 size_t bytes = 0;
620 ktime_t timestamp;
621
622 if (count != 0 && count < input_event_size())
623 return -EINVAL;
624
625 while (bytes + input_event_size() <= count) {
626 /*
627 * Note that even if some events were fetched successfully
628 * we are still going to return EFAULT instead of partial
629 * count to let userspace know that it got it's buffers
630 * all wrong.
631 */
632 if (input_event_from_user(buffer + bytes, &ev))
633 return -EFAULT;
634
635 timestamp = ktime_set(ev.input_event_sec, ev.input_event_usec * NSEC_PER_USEC);
636 if (is_valid_timestamp(timestamp))
637 input_set_timestamp(udev->dev, timestamp);
638
639 input_event(udev->dev, ev.type, ev.code, ev.value);
640 bytes += input_event_size();
641 cond_resched();
642 }
643
644 return bytes;
645}
646
647static ssize_t uinput_write(struct file *file, const char __user *buffer,
648 size_t count, loff_t *ppos)
649{
650 struct uinput_device *udev = file->private_data;
651 int retval;
652
653 if (count == 0)
654 return 0;
655
656 retval = mutex_lock_interruptible(&udev->mutex);
657 if (retval)
658 return retval;
659
660 retval = udev->state == UIST_CREATED ?
661 uinput_inject_events(udev, buffer, count) :
662 uinput_setup_device_legacy(udev, buffer, count);
663
664 mutex_unlock(&udev->mutex);
665
666 return retval;
667}
668
669static bool uinput_fetch_next_event(struct uinput_device *udev,
670 struct input_event *event)
671{
672 bool have_event;
673
674 spin_lock_irq(&udev->dev->event_lock);
675
676 have_event = udev->head != udev->tail;
677 if (have_event) {
678 *event = udev->buff[udev->tail];
679 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
680 }
681
682 spin_unlock_irq(&udev->dev->event_lock);
683
684 return have_event;
685}
686
687static ssize_t uinput_events_to_user(struct uinput_device *udev,
688 char __user *buffer, size_t count)
689{
690 struct input_event event;
691 size_t read = 0;
692
693 while (read + input_event_size() <= count &&
694 uinput_fetch_next_event(udev, &event)) {
695
696 if (input_event_to_user(buffer + read, &event))
697 return -EFAULT;
698
699 read += input_event_size();
700 }
701
702 return read;
703}
704
705static ssize_t uinput_read(struct file *file, char __user *buffer,
706 size_t count, loff_t *ppos)
707{
708 struct uinput_device *udev = file->private_data;
709 ssize_t retval;
710
711 if (count != 0 && count < input_event_size())
712 return -EINVAL;
713
714 do {
715 retval = mutex_lock_interruptible(&udev->mutex);
716 if (retval)
717 return retval;
718
719 if (udev->state != UIST_CREATED)
720 retval = -ENODEV;
721 else if (udev->head == udev->tail &&
722 (file->f_flags & O_NONBLOCK))
723 retval = -EAGAIN;
724 else
725 retval = uinput_events_to_user(udev, buffer, count);
726
727 mutex_unlock(&udev->mutex);
728
729 if (retval || count == 0)
730 break;
731
732 if (!(file->f_flags & O_NONBLOCK))
733 retval = wait_event_interruptible(udev->waitq,
734 udev->head != udev->tail ||
735 udev->state != UIST_CREATED);
736 } while (retval == 0);
737
738 return retval;
739}
740
741static __poll_t uinput_poll(struct file *file, poll_table *wait)
742{
743 struct uinput_device *udev = file->private_data;
744 __poll_t mask = EPOLLOUT | EPOLLWRNORM; /* uinput is always writable */
745
746 poll_wait(file, &udev->waitq, wait);
747
748 if (udev->head != udev->tail)
749 mask |= EPOLLIN | EPOLLRDNORM;
750
751 return mask;
752}
753
754static int uinput_release(struct inode *inode, struct file *file)
755{
756 struct uinput_device *udev = file->private_data;
757
758 uinput_destroy_device(udev);
759 kfree(udev);
760
761 return 0;
762}
763
764#ifdef CONFIG_COMPAT
765struct uinput_ff_upload_compat {
766 __u32 request_id;
767 __s32 retval;
768 struct ff_effect_compat effect;
769 struct ff_effect_compat old;
770};
771
772static int uinput_ff_upload_to_user(char __user *buffer,
773 const struct uinput_ff_upload *ff_up)
774{
775 if (in_compat_syscall()) {
776 struct uinput_ff_upload_compat ff_up_compat;
777
778 ff_up_compat.request_id = ff_up->request_id;
779 ff_up_compat.retval = ff_up->retval;
780 /*
781 * It so happens that the pointer that gives us the trouble
782 * is the last field in the structure. Since we don't support
783 * custom waveforms in uinput anyway we can just copy the whole
784 * thing (to the compat size) and ignore the pointer.
785 */
786 memcpy(&ff_up_compat.effect, &ff_up->effect,
787 sizeof(struct ff_effect_compat));
788 memcpy(&ff_up_compat.old, &ff_up->old,
789 sizeof(struct ff_effect_compat));
790
791 if (copy_to_user(buffer, &ff_up_compat,
792 sizeof(struct uinput_ff_upload_compat)))
793 return -EFAULT;
794 } else {
795 if (copy_to_user(buffer, ff_up,
796 sizeof(struct uinput_ff_upload)))
797 return -EFAULT;
798 }
799
800 return 0;
801}
802
803static int uinput_ff_upload_from_user(const char __user *buffer,
804 struct uinput_ff_upload *ff_up)
805{
806 if (in_compat_syscall()) {
807 struct uinput_ff_upload_compat ff_up_compat;
808
809 if (copy_from_user(&ff_up_compat, buffer,
810 sizeof(struct uinput_ff_upload_compat)))
811 return -EFAULT;
812
813 ff_up->request_id = ff_up_compat.request_id;
814 ff_up->retval = ff_up_compat.retval;
815 memcpy(&ff_up->effect, &ff_up_compat.effect,
816 sizeof(struct ff_effect_compat));
817 memcpy(&ff_up->old, &ff_up_compat.old,
818 sizeof(struct ff_effect_compat));
819
820 } else {
821 if (copy_from_user(ff_up, buffer,
822 sizeof(struct uinput_ff_upload)))
823 return -EFAULT;
824 }
825
826 return 0;
827}
828
829#else
830
831static int uinput_ff_upload_to_user(char __user *buffer,
832 const struct uinput_ff_upload *ff_up)
833{
834 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
835 return -EFAULT;
836
837 return 0;
838}
839
840static int uinput_ff_upload_from_user(const char __user *buffer,
841 struct uinput_ff_upload *ff_up)
842{
843 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
844 return -EFAULT;
845
846 return 0;
847}
848
849#endif
850
851#define uinput_set_bit(_arg, _bit, _max) \
852({ \
853 int __ret = 0; \
854 if (udev->state == UIST_CREATED) \
855 __ret = -EINVAL; \
856 else if ((_arg) > (_max)) \
857 __ret = -EINVAL; \
858 else set_bit((_arg), udev->dev->_bit); \
859 __ret; \
860})
861
862static int uinput_str_to_user(void __user *dest, const char *str,
863 unsigned int maxlen)
864{
865 char __user *p = dest;
866 int len, ret;
867
868 if (!str)
869 return -ENOENT;
870
871 if (maxlen == 0)
872 return -EINVAL;
873
874 len = strlen(str) + 1;
875 if (len > maxlen)
876 len = maxlen;
877
878 ret = copy_to_user(p, str, len);
879 if (ret)
880 return -EFAULT;
881
882 /* force terminating '\0' */
883 ret = put_user(0, p + len - 1);
884 return ret ? -EFAULT : len;
885}
886
887static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
888 unsigned long arg, void __user *p)
889{
890 int retval;
891 struct uinput_device *udev = file->private_data;
892 struct uinput_ff_upload ff_up;
893 struct uinput_ff_erase ff_erase;
894 struct uinput_request *req;
895 char *phys;
896 const char *name;
897 unsigned int size;
898
899 retval = mutex_lock_interruptible(&udev->mutex);
900 if (retval)
901 return retval;
902
903 if (!udev->dev) {
904 udev->dev = input_allocate_device();
905 if (!udev->dev) {
906 retval = -ENOMEM;
907 goto out;
908 }
909 }
910
911 switch (cmd) {
912 case UI_GET_VERSION:
913 if (put_user(UINPUT_VERSION, (unsigned int __user *)p))
914 retval = -EFAULT;
915 goto out;
916
917 case UI_DEV_CREATE:
918 retval = uinput_create_device(udev);
919 goto out;
920
921 case UI_DEV_DESTROY:
922 uinput_destroy_device(udev);
923 goto out;
924
925 case UI_DEV_SETUP:
926 retval = uinput_dev_setup(udev, p);
927 goto out;
928
929 /* UI_ABS_SETUP is handled in the variable size ioctls */
930
931 case UI_SET_EVBIT:
932 retval = uinput_set_bit(arg, evbit, EV_MAX);
933 goto out;
934
935 case UI_SET_KEYBIT:
936 retval = uinput_set_bit(arg, keybit, KEY_MAX);
937 goto out;
938
939 case UI_SET_RELBIT:
940 retval = uinput_set_bit(arg, relbit, REL_MAX);
941 goto out;
942
943 case UI_SET_ABSBIT:
944 retval = uinput_set_bit(arg, absbit, ABS_MAX);
945 goto out;
946
947 case UI_SET_MSCBIT:
948 retval = uinput_set_bit(arg, mscbit, MSC_MAX);
949 goto out;
950
951 case UI_SET_LEDBIT:
952 retval = uinput_set_bit(arg, ledbit, LED_MAX);
953 goto out;
954
955 case UI_SET_SNDBIT:
956 retval = uinput_set_bit(arg, sndbit, SND_MAX);
957 goto out;
958
959 case UI_SET_FFBIT:
960 retval = uinput_set_bit(arg, ffbit, FF_MAX);
961 goto out;
962
963 case UI_SET_SWBIT:
964 retval = uinput_set_bit(arg, swbit, SW_MAX);
965 goto out;
966
967 case UI_SET_PROPBIT:
968 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
969 goto out;
970
971 case UI_SET_PHYS:
972 if (udev->state == UIST_CREATED) {
973 retval = -EINVAL;
974 goto out;
975 }
976
977 phys = strndup_user(p, 1024);
978 if (IS_ERR(phys)) {
979 retval = PTR_ERR(phys);
980 goto out;
981 }
982
983 kfree(udev->dev->phys);
984 udev->dev->phys = phys;
985 goto out;
986
987 case UI_BEGIN_FF_UPLOAD:
988 retval = uinput_ff_upload_from_user(p, &ff_up);
989 if (retval)
990 goto out;
991
992 req = uinput_request_find(udev, ff_up.request_id);
993 if (!req || req->code != UI_FF_UPLOAD ||
994 !req->u.upload.effect) {
995 retval = -EINVAL;
996 goto out;
997 }
998
999 ff_up.retval = 0;
1000 ff_up.effect = *req->u.upload.effect;
1001 if (req->u.upload.old)
1002 ff_up.old = *req->u.upload.old;
1003 else
1004 memset(&ff_up.old, 0, sizeof(struct ff_effect));
1005
1006 retval = uinput_ff_upload_to_user(p, &ff_up);
1007 goto out;
1008
1009 case UI_BEGIN_FF_ERASE:
1010 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
1011 retval = -EFAULT;
1012 goto out;
1013 }
1014
1015 req = uinput_request_find(udev, ff_erase.request_id);
1016 if (!req || req->code != UI_FF_ERASE) {
1017 retval = -EINVAL;
1018 goto out;
1019 }
1020
1021 ff_erase.retval = 0;
1022 ff_erase.effect_id = req->u.effect_id;
1023 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
1024 retval = -EFAULT;
1025 goto out;
1026 }
1027
1028 goto out;
1029
1030 case UI_END_FF_UPLOAD:
1031 retval = uinput_ff_upload_from_user(p, &ff_up);
1032 if (retval)
1033 goto out;
1034
1035 req = uinput_request_find(udev, ff_up.request_id);
1036 if (!req || req->code != UI_FF_UPLOAD ||
1037 !req->u.upload.effect) {
1038 retval = -EINVAL;
1039 goto out;
1040 }
1041
1042 req->retval = ff_up.retval;
1043 complete(&req->done);
1044 goto out;
1045
1046 case UI_END_FF_ERASE:
1047 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
1048 retval = -EFAULT;
1049 goto out;
1050 }
1051
1052 req = uinput_request_find(udev, ff_erase.request_id);
1053 if (!req || req->code != UI_FF_ERASE) {
1054 retval = -EINVAL;
1055 goto out;
1056 }
1057
1058 req->retval = ff_erase.retval;
1059 complete(&req->done);
1060 goto out;
1061 }
1062
1063 size = _IOC_SIZE(cmd);
1064
1065 /* Now check variable-length commands */
1066 switch (cmd & ~IOCSIZE_MASK) {
1067 case UI_GET_SYSNAME(0):
1068 if (udev->state != UIST_CREATED) {
1069 retval = -ENOENT;
1070 goto out;
1071 }
1072 name = dev_name(&udev->dev->dev);
1073 retval = uinput_str_to_user(p, name, size);
1074 goto out;
1075
1076 case UI_ABS_SETUP & ~IOCSIZE_MASK:
1077 retval = uinput_abs_setup(udev, p, size);
1078 goto out;
1079 }
1080
1081 retval = -EINVAL;
1082 out:
1083 mutex_unlock(&udev->mutex);
1084 return retval;
1085}
1086
1087static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1088{
1089 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
1090}
1091
1092#ifdef CONFIG_COMPAT
1093
1094/*
1095 * These IOCTLs change their size and thus their numbers between
1096 * 32 and 64 bits.
1097 */
1098#define UI_SET_PHYS_COMPAT \
1099 _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t)
1100#define UI_BEGIN_FF_UPLOAD_COMPAT \
1101 _IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload_compat)
1102#define UI_END_FF_UPLOAD_COMPAT \
1103 _IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload_compat)
1104
1105static long uinput_compat_ioctl(struct file *file,
1106 unsigned int cmd, unsigned long arg)
1107{
1108 switch (cmd) {
1109 case UI_SET_PHYS_COMPAT:
1110 cmd = UI_SET_PHYS;
1111 break;
1112 case UI_BEGIN_FF_UPLOAD_COMPAT:
1113 cmd = UI_BEGIN_FF_UPLOAD;
1114 break;
1115 case UI_END_FF_UPLOAD_COMPAT:
1116 cmd = UI_END_FF_UPLOAD;
1117 break;
1118 }
1119
1120 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
1121}
1122#endif
1123
1124static const struct file_operations uinput_fops = {
1125 .owner = THIS_MODULE,
1126 .open = uinput_open,
1127 .release = uinput_release,
1128 .read = uinput_read,
1129 .write = uinput_write,
1130 .poll = uinput_poll,
1131 .unlocked_ioctl = uinput_ioctl,
1132#ifdef CONFIG_COMPAT
1133 .compat_ioctl = uinput_compat_ioctl,
1134#endif
1135};
1136
1137static struct miscdevice uinput_misc = {
1138 .fops = &uinput_fops,
1139 .minor = UINPUT_MINOR,
1140 .name = UINPUT_NAME,
1141};
1142module_misc_device(uinput_misc);
1143
1144MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1145MODULE_ALIAS("devname:" UINPUT_NAME);
1146
1147MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1148MODULE_DESCRIPTION("User level driver support for input subsystem");
1149MODULE_LICENSE("GPL");
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);