Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame^] | 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 <uapi/linux/uinput.h> |
| 35 | #include <linux/poll.h> |
| 36 | #include <linux/sched.h> |
| 37 | #include <linux/slab.h> |
| 38 | #include <linux/module.h> |
| 39 | #include <linux/init.h> |
| 40 | #include <linux/fs.h> |
| 41 | #include <linux/miscdevice.h> |
| 42 | #include <linux/input/mt.h> |
| 43 | #include "../input-compat.h" |
| 44 | |
| 45 | #define UINPUT_NAME "uinput" |
| 46 | #define UINPUT_BUFFER_SIZE 16 |
| 47 | #define UINPUT_NUM_REQUESTS 16 |
| 48 | |
| 49 | enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED }; |
| 50 | |
| 51 | struct uinput_request { |
| 52 | unsigned int id; |
| 53 | unsigned int code; /* UI_FF_UPLOAD, UI_FF_ERASE */ |
| 54 | |
| 55 | int retval; |
| 56 | struct completion done; |
| 57 | |
| 58 | union { |
| 59 | unsigned int effect_id; |
| 60 | struct { |
| 61 | struct ff_effect *effect; |
| 62 | struct ff_effect *old; |
| 63 | } upload; |
| 64 | } u; |
| 65 | }; |
| 66 | |
| 67 | struct uinput_device { |
| 68 | struct input_dev *dev; |
| 69 | struct mutex mutex; |
| 70 | enum uinput_state state; |
| 71 | wait_queue_head_t waitq; |
| 72 | unsigned char ready; |
| 73 | unsigned char head; |
| 74 | unsigned char tail; |
| 75 | struct input_event buff[UINPUT_BUFFER_SIZE]; |
| 76 | unsigned int ff_effects_max; |
| 77 | |
| 78 | struct uinput_request *requests[UINPUT_NUM_REQUESTS]; |
| 79 | wait_queue_head_t requests_waitq; |
| 80 | spinlock_t requests_lock; |
| 81 | }; |
| 82 | |
| 83 | static int uinput_dev_event(struct input_dev *dev, |
| 84 | unsigned int type, unsigned int code, int value) |
| 85 | { |
| 86 | struct uinput_device *udev = input_get_drvdata(dev); |
| 87 | struct timespec64 ts; |
| 88 | |
| 89 | udev->buff[udev->head].type = type; |
| 90 | udev->buff[udev->head].code = code; |
| 91 | udev->buff[udev->head].value = value; |
| 92 | ktime_get_ts64(&ts); |
| 93 | udev->buff[udev->head].input_event_sec = ts.tv_sec; |
| 94 | udev->buff[udev->head].input_event_usec = ts.tv_nsec / NSEC_PER_USEC; |
| 95 | udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE; |
| 96 | |
| 97 | wake_up_interruptible(&udev->waitq); |
| 98 | |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | /* Atomically allocate an ID for the given request. Returns 0 on success. */ |
| 103 | static bool uinput_request_alloc_id(struct uinput_device *udev, |
| 104 | struct uinput_request *request) |
| 105 | { |
| 106 | unsigned int id; |
| 107 | bool reserved = false; |
| 108 | |
| 109 | spin_lock(&udev->requests_lock); |
| 110 | |
| 111 | for (id = 0; id < UINPUT_NUM_REQUESTS; id++) { |
| 112 | if (!udev->requests[id]) { |
| 113 | request->id = id; |
| 114 | udev->requests[id] = request; |
| 115 | reserved = true; |
| 116 | break; |
| 117 | } |
| 118 | } |
| 119 | |
| 120 | spin_unlock(&udev->requests_lock); |
| 121 | return reserved; |
| 122 | } |
| 123 | |
| 124 | static struct uinput_request *uinput_request_find(struct uinput_device *udev, |
| 125 | unsigned int id) |
| 126 | { |
| 127 | /* Find an input request, by ID. Returns NULL if the ID isn't valid. */ |
| 128 | if (id >= UINPUT_NUM_REQUESTS) |
| 129 | return NULL; |
| 130 | |
| 131 | return udev->requests[id]; |
| 132 | } |
| 133 | |
| 134 | static int uinput_request_reserve_slot(struct uinput_device *udev, |
| 135 | struct uinput_request *request) |
| 136 | { |
| 137 | /* Allocate slot. If none are available right away, wait. */ |
| 138 | return wait_event_interruptible(udev->requests_waitq, |
| 139 | uinput_request_alloc_id(udev, request)); |
| 140 | } |
| 141 | |
| 142 | static void uinput_request_release_slot(struct uinput_device *udev, |
| 143 | unsigned int id) |
| 144 | { |
| 145 | /* Mark slot as available */ |
| 146 | spin_lock(&udev->requests_lock); |
| 147 | udev->requests[id] = NULL; |
| 148 | spin_unlock(&udev->requests_lock); |
| 149 | |
| 150 | wake_up(&udev->requests_waitq); |
| 151 | } |
| 152 | |
| 153 | static int uinput_request_send(struct uinput_device *udev, |
| 154 | struct uinput_request *request) |
| 155 | { |
| 156 | int retval; |
| 157 | |
| 158 | retval = mutex_lock_interruptible(&udev->mutex); |
| 159 | if (retval) |
| 160 | return retval; |
| 161 | |
| 162 | if (udev->state != UIST_CREATED) { |
| 163 | retval = -ENODEV; |
| 164 | goto out; |
| 165 | } |
| 166 | |
| 167 | init_completion(&request->done); |
| 168 | |
| 169 | /* |
| 170 | * Tell our userspace application about this new request |
| 171 | * by queueing an input event. |
| 172 | */ |
| 173 | uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id); |
| 174 | |
| 175 | out: |
| 176 | mutex_unlock(&udev->mutex); |
| 177 | return retval; |
| 178 | } |
| 179 | |
| 180 | static int uinput_request_submit(struct uinput_device *udev, |
| 181 | struct uinput_request *request) |
| 182 | { |
| 183 | int retval; |
| 184 | |
| 185 | retval = uinput_request_reserve_slot(udev, request); |
| 186 | if (retval) |
| 187 | return retval; |
| 188 | |
| 189 | retval = uinput_request_send(udev, request); |
| 190 | if (retval) |
| 191 | goto out; |
| 192 | |
| 193 | if (!wait_for_completion_timeout(&request->done, 30 * HZ)) { |
| 194 | retval = -ETIMEDOUT; |
| 195 | goto out; |
| 196 | } |
| 197 | |
| 198 | retval = request->retval; |
| 199 | |
| 200 | out: |
| 201 | uinput_request_release_slot(udev, request->id); |
| 202 | return retval; |
| 203 | } |
| 204 | |
| 205 | /* |
| 206 | * Fail all outstanding requests so handlers don't wait for the userspace |
| 207 | * to finish processing them. |
| 208 | */ |
| 209 | static void uinput_flush_requests(struct uinput_device *udev) |
| 210 | { |
| 211 | struct uinput_request *request; |
| 212 | int i; |
| 213 | |
| 214 | spin_lock(&udev->requests_lock); |
| 215 | |
| 216 | for (i = 0; i < UINPUT_NUM_REQUESTS; i++) { |
| 217 | request = udev->requests[i]; |
| 218 | if (request) { |
| 219 | request->retval = -ENODEV; |
| 220 | complete(&request->done); |
| 221 | } |
| 222 | } |
| 223 | |
| 224 | spin_unlock(&udev->requests_lock); |
| 225 | } |
| 226 | |
| 227 | static void uinput_dev_set_gain(struct input_dev *dev, u16 gain) |
| 228 | { |
| 229 | uinput_dev_event(dev, EV_FF, FF_GAIN, gain); |
| 230 | } |
| 231 | |
| 232 | static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude) |
| 233 | { |
| 234 | uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude); |
| 235 | } |
| 236 | |
| 237 | static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value) |
| 238 | { |
| 239 | return uinput_dev_event(dev, EV_FF, effect_id, value); |
| 240 | } |
| 241 | |
| 242 | static int uinput_dev_upload_effect(struct input_dev *dev, |
| 243 | struct ff_effect *effect, |
| 244 | struct ff_effect *old) |
| 245 | { |
| 246 | struct uinput_device *udev = input_get_drvdata(dev); |
| 247 | struct uinput_request request; |
| 248 | |
| 249 | /* |
| 250 | * uinput driver does not currently support periodic effects with |
| 251 | * custom waveform since it does not have a way to pass buffer of |
| 252 | * samples (custom_data) to userspace. If ever there is a device |
| 253 | * supporting custom waveforms we would need to define an additional |
| 254 | * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out. |
| 255 | */ |
| 256 | if (effect->type == FF_PERIODIC && |
| 257 | effect->u.periodic.waveform == FF_CUSTOM) |
| 258 | return -EINVAL; |
| 259 | |
| 260 | request.code = UI_FF_UPLOAD; |
| 261 | request.u.upload.effect = effect; |
| 262 | request.u.upload.old = old; |
| 263 | |
| 264 | return uinput_request_submit(udev, &request); |
| 265 | } |
| 266 | |
| 267 | static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id) |
| 268 | { |
| 269 | struct uinput_device *udev = input_get_drvdata(dev); |
| 270 | struct uinput_request request; |
| 271 | |
| 272 | if (!test_bit(EV_FF, dev->evbit)) |
| 273 | return -ENOSYS; |
| 274 | |
| 275 | request.code = UI_FF_ERASE; |
| 276 | request.u.effect_id = effect_id; |
| 277 | |
| 278 | return uinput_request_submit(udev, &request); |
| 279 | } |
| 280 | |
| 281 | static int uinput_dev_flush(struct input_dev *dev, struct file *file) |
| 282 | { |
| 283 | /* |
| 284 | * If we are called with file == NULL that means we are tearing |
| 285 | * down the device, and therefore we can not handle FF erase |
| 286 | * requests: either we are handling UI_DEV_DESTROY (and holding |
| 287 | * the udev->mutex), or the file descriptor is closed and there is |
| 288 | * nobody on the other side anymore. |
| 289 | */ |
| 290 | return file ? input_ff_flush(dev, file) : 0; |
| 291 | } |
| 292 | |
| 293 | static void uinput_destroy_device(struct uinput_device *udev) |
| 294 | { |
| 295 | const char *name, *phys; |
| 296 | struct input_dev *dev = udev->dev; |
| 297 | enum uinput_state old_state = udev->state; |
| 298 | |
| 299 | udev->state = UIST_NEW_DEVICE; |
| 300 | |
| 301 | if (dev) { |
| 302 | name = dev->name; |
| 303 | phys = dev->phys; |
| 304 | if (old_state == UIST_CREATED) { |
| 305 | uinput_flush_requests(udev); |
| 306 | input_unregister_device(dev); |
| 307 | } else { |
| 308 | input_free_device(dev); |
| 309 | } |
| 310 | kfree(name); |
| 311 | kfree(phys); |
| 312 | udev->dev = NULL; |
| 313 | } |
| 314 | } |
| 315 | |
| 316 | static int uinput_create_device(struct uinput_device *udev) |
| 317 | { |
| 318 | struct input_dev *dev = udev->dev; |
| 319 | int error, nslot; |
| 320 | |
| 321 | if (udev->state != UIST_SETUP_COMPLETE) { |
| 322 | printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME); |
| 323 | return -EINVAL; |
| 324 | } |
| 325 | |
| 326 | if (test_bit(EV_ABS, dev->evbit)) { |
| 327 | input_alloc_absinfo(dev); |
| 328 | if (!dev->absinfo) { |
| 329 | error = -EINVAL; |
| 330 | goto fail1; |
| 331 | } |
| 332 | |
| 333 | if (test_bit(ABS_MT_SLOT, dev->absbit)) { |
| 334 | nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1; |
| 335 | error = input_mt_init_slots(dev, nslot, 0); |
| 336 | if (error) |
| 337 | goto fail1; |
| 338 | } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) { |
| 339 | input_set_events_per_packet(dev, 60); |
| 340 | } |
| 341 | } |
| 342 | |
| 343 | if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) { |
| 344 | printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n", |
| 345 | UINPUT_NAME); |
| 346 | error = -EINVAL; |
| 347 | goto fail1; |
| 348 | } |
| 349 | |
| 350 | if (udev->ff_effects_max) { |
| 351 | error = input_ff_create(dev, udev->ff_effects_max); |
| 352 | if (error) |
| 353 | goto fail1; |
| 354 | |
| 355 | dev->ff->upload = uinput_dev_upload_effect; |
| 356 | dev->ff->erase = uinput_dev_erase_effect; |
| 357 | dev->ff->playback = uinput_dev_playback; |
| 358 | dev->ff->set_gain = uinput_dev_set_gain; |
| 359 | dev->ff->set_autocenter = uinput_dev_set_autocenter; |
| 360 | /* |
| 361 | * The standard input_ff_flush() implementation does |
| 362 | * not quite work for uinput as we can't reasonably |
| 363 | * handle FF requests during device teardown. |
| 364 | */ |
| 365 | dev->flush = uinput_dev_flush; |
| 366 | } |
| 367 | |
| 368 | dev->event = uinput_dev_event; |
| 369 | |
| 370 | input_set_drvdata(udev->dev, udev); |
| 371 | |
| 372 | error = input_register_device(udev->dev); |
| 373 | if (error) |
| 374 | goto fail2; |
| 375 | |
| 376 | udev->state = UIST_CREATED; |
| 377 | |
| 378 | return 0; |
| 379 | |
| 380 | fail2: input_ff_destroy(dev); |
| 381 | fail1: uinput_destroy_device(udev); |
| 382 | return error; |
| 383 | } |
| 384 | |
| 385 | static int uinput_open(struct inode *inode, struct file *file) |
| 386 | { |
| 387 | struct uinput_device *newdev; |
| 388 | |
| 389 | newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL); |
| 390 | if (!newdev) |
| 391 | return -ENOMEM; |
| 392 | |
| 393 | mutex_init(&newdev->mutex); |
| 394 | spin_lock_init(&newdev->requests_lock); |
| 395 | init_waitqueue_head(&newdev->requests_waitq); |
| 396 | init_waitqueue_head(&newdev->waitq); |
| 397 | newdev->state = UIST_NEW_DEVICE; |
| 398 | |
| 399 | file->private_data = newdev; |
| 400 | nonseekable_open(inode, file); |
| 401 | |
| 402 | return 0; |
| 403 | } |
| 404 | |
| 405 | static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code, |
| 406 | const struct input_absinfo *abs) |
| 407 | { |
| 408 | int min, max; |
| 409 | |
| 410 | min = abs->minimum; |
| 411 | max = abs->maximum; |
| 412 | |
| 413 | if ((min != 0 || max != 0) && max < min) { |
| 414 | printk(KERN_DEBUG |
| 415 | "%s: invalid abs[%02x] min:%d max:%d\n", |
| 416 | UINPUT_NAME, code, min, max); |
| 417 | return -EINVAL; |
| 418 | } |
| 419 | |
| 420 | if (abs->flat > max - min) { |
| 421 | printk(KERN_DEBUG |
| 422 | "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n", |
| 423 | UINPUT_NAME, code, abs->flat, min, max); |
| 424 | return -EINVAL; |
| 425 | } |
| 426 | |
| 427 | return 0; |
| 428 | } |
| 429 | |
| 430 | static int uinput_validate_absbits(struct input_dev *dev) |
| 431 | { |
| 432 | unsigned int cnt; |
| 433 | int error; |
| 434 | |
| 435 | if (!test_bit(EV_ABS, dev->evbit)) |
| 436 | return 0; |
| 437 | |
| 438 | /* |
| 439 | * Check if absmin/absmax/absfuzz/absflat are sane. |
| 440 | */ |
| 441 | |
| 442 | for_each_set_bit(cnt, dev->absbit, ABS_CNT) { |
| 443 | if (!dev->absinfo) |
| 444 | return -EINVAL; |
| 445 | |
| 446 | error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]); |
| 447 | if (error) |
| 448 | return error; |
| 449 | } |
| 450 | |
| 451 | return 0; |
| 452 | } |
| 453 | |
| 454 | static int uinput_dev_setup(struct uinput_device *udev, |
| 455 | struct uinput_setup __user *arg) |
| 456 | { |
| 457 | struct uinput_setup setup; |
| 458 | struct input_dev *dev; |
| 459 | |
| 460 | if (udev->state == UIST_CREATED) |
| 461 | return -EINVAL; |
| 462 | |
| 463 | if (copy_from_user(&setup, arg, sizeof(setup))) |
| 464 | return -EFAULT; |
| 465 | |
| 466 | if (!setup.name[0]) |
| 467 | return -EINVAL; |
| 468 | |
| 469 | dev = udev->dev; |
| 470 | dev->id = setup.id; |
| 471 | udev->ff_effects_max = setup.ff_effects_max; |
| 472 | |
| 473 | kfree(dev->name); |
| 474 | dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL); |
| 475 | if (!dev->name) |
| 476 | return -ENOMEM; |
| 477 | |
| 478 | udev->state = UIST_SETUP_COMPLETE; |
| 479 | return 0; |
| 480 | } |
| 481 | |
| 482 | static int uinput_abs_setup(struct uinput_device *udev, |
| 483 | struct uinput_setup __user *arg, size_t size) |
| 484 | { |
| 485 | struct uinput_abs_setup setup = {}; |
| 486 | struct input_dev *dev; |
| 487 | int error; |
| 488 | |
| 489 | if (size > sizeof(setup)) |
| 490 | return -E2BIG; |
| 491 | |
| 492 | if (udev->state == UIST_CREATED) |
| 493 | return -EINVAL; |
| 494 | |
| 495 | if (copy_from_user(&setup, arg, size)) |
| 496 | return -EFAULT; |
| 497 | |
| 498 | if (setup.code > ABS_MAX) |
| 499 | return -ERANGE; |
| 500 | |
| 501 | dev = udev->dev; |
| 502 | |
| 503 | error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo); |
| 504 | if (error) |
| 505 | return error; |
| 506 | |
| 507 | input_alloc_absinfo(dev); |
| 508 | if (!dev->absinfo) |
| 509 | return -ENOMEM; |
| 510 | |
| 511 | set_bit(setup.code, dev->absbit); |
| 512 | dev->absinfo[setup.code] = setup.absinfo; |
| 513 | return 0; |
| 514 | } |
| 515 | |
| 516 | /* legacy setup via write() */ |
| 517 | static int uinput_setup_device_legacy(struct uinput_device *udev, |
| 518 | const char __user *buffer, size_t count) |
| 519 | { |
| 520 | struct uinput_user_dev *user_dev; |
| 521 | struct input_dev *dev; |
| 522 | int i; |
| 523 | int retval; |
| 524 | |
| 525 | if (count != sizeof(struct uinput_user_dev)) |
| 526 | return -EINVAL; |
| 527 | |
| 528 | if (!udev->dev) { |
| 529 | udev->dev = input_allocate_device(); |
| 530 | if (!udev->dev) |
| 531 | return -ENOMEM; |
| 532 | } |
| 533 | |
| 534 | dev = udev->dev; |
| 535 | |
| 536 | user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev)); |
| 537 | if (IS_ERR(user_dev)) |
| 538 | return PTR_ERR(user_dev); |
| 539 | |
| 540 | udev->ff_effects_max = user_dev->ff_effects_max; |
| 541 | |
| 542 | /* Ensure name is filled in */ |
| 543 | if (!user_dev->name[0]) { |
| 544 | retval = -EINVAL; |
| 545 | goto exit; |
| 546 | } |
| 547 | |
| 548 | kfree(dev->name); |
| 549 | dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE, |
| 550 | GFP_KERNEL); |
| 551 | if (!dev->name) { |
| 552 | retval = -ENOMEM; |
| 553 | goto exit; |
| 554 | } |
| 555 | |
| 556 | dev->id.bustype = user_dev->id.bustype; |
| 557 | dev->id.vendor = user_dev->id.vendor; |
| 558 | dev->id.product = user_dev->id.product; |
| 559 | dev->id.version = user_dev->id.version; |
| 560 | |
| 561 | for (i = 0; i < ABS_CNT; i++) { |
| 562 | input_abs_set_max(dev, i, user_dev->absmax[i]); |
| 563 | input_abs_set_min(dev, i, user_dev->absmin[i]); |
| 564 | input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]); |
| 565 | input_abs_set_flat(dev, i, user_dev->absflat[i]); |
| 566 | } |
| 567 | |
| 568 | retval = uinput_validate_absbits(dev); |
| 569 | if (retval < 0) |
| 570 | goto exit; |
| 571 | |
| 572 | udev->state = UIST_SETUP_COMPLETE; |
| 573 | retval = count; |
| 574 | |
| 575 | exit: |
| 576 | kfree(user_dev); |
| 577 | return retval; |
| 578 | } |
| 579 | |
| 580 | static ssize_t uinput_inject_events(struct uinput_device *udev, |
| 581 | const char __user *buffer, size_t count) |
| 582 | { |
| 583 | struct input_event ev; |
| 584 | size_t bytes = 0; |
| 585 | |
| 586 | if (count != 0 && count < input_event_size()) |
| 587 | return -EINVAL; |
| 588 | |
| 589 | while (bytes + input_event_size() <= count) { |
| 590 | /* |
| 591 | * Note that even if some events were fetched successfully |
| 592 | * we are still going to return EFAULT instead of partial |
| 593 | * count to let userspace know that it got it's buffers |
| 594 | * all wrong. |
| 595 | */ |
| 596 | if (input_event_from_user(buffer + bytes, &ev)) |
| 597 | return -EFAULT; |
| 598 | |
| 599 | input_event(udev->dev, ev.type, ev.code, ev.value); |
| 600 | bytes += input_event_size(); |
| 601 | cond_resched(); |
| 602 | } |
| 603 | |
| 604 | return bytes; |
| 605 | } |
| 606 | |
| 607 | static ssize_t uinput_write(struct file *file, const char __user *buffer, |
| 608 | size_t count, loff_t *ppos) |
| 609 | { |
| 610 | struct uinput_device *udev = file->private_data; |
| 611 | int retval; |
| 612 | |
| 613 | if (count == 0) |
| 614 | return 0; |
| 615 | |
| 616 | retval = mutex_lock_interruptible(&udev->mutex); |
| 617 | if (retval) |
| 618 | return retval; |
| 619 | |
| 620 | retval = udev->state == UIST_CREATED ? |
| 621 | uinput_inject_events(udev, buffer, count) : |
| 622 | uinput_setup_device_legacy(udev, buffer, count); |
| 623 | |
| 624 | mutex_unlock(&udev->mutex); |
| 625 | |
| 626 | return retval; |
| 627 | } |
| 628 | |
| 629 | static bool uinput_fetch_next_event(struct uinput_device *udev, |
| 630 | struct input_event *event) |
| 631 | { |
| 632 | bool have_event; |
| 633 | |
| 634 | spin_lock_irq(&udev->dev->event_lock); |
| 635 | |
| 636 | have_event = udev->head != udev->tail; |
| 637 | if (have_event) { |
| 638 | *event = udev->buff[udev->tail]; |
| 639 | udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; |
| 640 | } |
| 641 | |
| 642 | spin_unlock_irq(&udev->dev->event_lock); |
| 643 | |
| 644 | return have_event; |
| 645 | } |
| 646 | |
| 647 | static ssize_t uinput_events_to_user(struct uinput_device *udev, |
| 648 | char __user *buffer, size_t count) |
| 649 | { |
| 650 | struct input_event event; |
| 651 | size_t read = 0; |
| 652 | |
| 653 | while (read + input_event_size() <= count && |
| 654 | uinput_fetch_next_event(udev, &event)) { |
| 655 | |
| 656 | if (input_event_to_user(buffer + read, &event)) |
| 657 | return -EFAULT; |
| 658 | |
| 659 | read += input_event_size(); |
| 660 | } |
| 661 | |
| 662 | return read; |
| 663 | } |
| 664 | |
| 665 | static ssize_t uinput_read(struct file *file, char __user *buffer, |
| 666 | size_t count, loff_t *ppos) |
| 667 | { |
| 668 | struct uinput_device *udev = file->private_data; |
| 669 | ssize_t retval; |
| 670 | |
| 671 | if (count != 0 && count < input_event_size()) |
| 672 | return -EINVAL; |
| 673 | |
| 674 | do { |
| 675 | retval = mutex_lock_interruptible(&udev->mutex); |
| 676 | if (retval) |
| 677 | return retval; |
| 678 | |
| 679 | if (udev->state != UIST_CREATED) |
| 680 | retval = -ENODEV; |
| 681 | else if (udev->head == udev->tail && |
| 682 | (file->f_flags & O_NONBLOCK)) |
| 683 | retval = -EAGAIN; |
| 684 | else |
| 685 | retval = uinput_events_to_user(udev, buffer, count); |
| 686 | |
| 687 | mutex_unlock(&udev->mutex); |
| 688 | |
| 689 | if (retval || count == 0) |
| 690 | break; |
| 691 | |
| 692 | if (!(file->f_flags & O_NONBLOCK)) |
| 693 | retval = wait_event_interruptible(udev->waitq, |
| 694 | udev->head != udev->tail || |
| 695 | udev->state != UIST_CREATED); |
| 696 | } while (retval == 0); |
| 697 | |
| 698 | return retval; |
| 699 | } |
| 700 | |
| 701 | static __poll_t uinput_poll(struct file *file, poll_table *wait) |
| 702 | { |
| 703 | struct uinput_device *udev = file->private_data; |
| 704 | |
| 705 | poll_wait(file, &udev->waitq, wait); |
| 706 | |
| 707 | if (udev->head != udev->tail) |
| 708 | return EPOLLIN | EPOLLRDNORM; |
| 709 | |
| 710 | return 0; |
| 711 | } |
| 712 | |
| 713 | static int uinput_release(struct inode *inode, struct file *file) |
| 714 | { |
| 715 | struct uinput_device *udev = file->private_data; |
| 716 | |
| 717 | uinput_destroy_device(udev); |
| 718 | kfree(udev); |
| 719 | |
| 720 | return 0; |
| 721 | } |
| 722 | |
| 723 | #ifdef CONFIG_COMPAT |
| 724 | struct uinput_ff_upload_compat { |
| 725 | __u32 request_id; |
| 726 | __s32 retval; |
| 727 | struct ff_effect_compat effect; |
| 728 | struct ff_effect_compat old; |
| 729 | }; |
| 730 | |
| 731 | static int uinput_ff_upload_to_user(char __user *buffer, |
| 732 | const struct uinput_ff_upload *ff_up) |
| 733 | { |
| 734 | if (in_compat_syscall()) { |
| 735 | struct uinput_ff_upload_compat ff_up_compat; |
| 736 | |
| 737 | ff_up_compat.request_id = ff_up->request_id; |
| 738 | ff_up_compat.retval = ff_up->retval; |
| 739 | /* |
| 740 | * It so happens that the pointer that gives us the trouble |
| 741 | * is the last field in the structure. Since we don't support |
| 742 | * custom waveforms in uinput anyway we can just copy the whole |
| 743 | * thing (to the compat size) and ignore the pointer. |
| 744 | */ |
| 745 | memcpy(&ff_up_compat.effect, &ff_up->effect, |
| 746 | sizeof(struct ff_effect_compat)); |
| 747 | memcpy(&ff_up_compat.old, &ff_up->old, |
| 748 | sizeof(struct ff_effect_compat)); |
| 749 | |
| 750 | if (copy_to_user(buffer, &ff_up_compat, |
| 751 | sizeof(struct uinput_ff_upload_compat))) |
| 752 | return -EFAULT; |
| 753 | } else { |
| 754 | if (copy_to_user(buffer, ff_up, |
| 755 | sizeof(struct uinput_ff_upload))) |
| 756 | return -EFAULT; |
| 757 | } |
| 758 | |
| 759 | return 0; |
| 760 | } |
| 761 | |
| 762 | static int uinput_ff_upload_from_user(const char __user *buffer, |
| 763 | struct uinput_ff_upload *ff_up) |
| 764 | { |
| 765 | if (in_compat_syscall()) { |
| 766 | struct uinput_ff_upload_compat ff_up_compat; |
| 767 | |
| 768 | if (copy_from_user(&ff_up_compat, buffer, |
| 769 | sizeof(struct uinput_ff_upload_compat))) |
| 770 | return -EFAULT; |
| 771 | |
| 772 | ff_up->request_id = ff_up_compat.request_id; |
| 773 | ff_up->retval = ff_up_compat.retval; |
| 774 | memcpy(&ff_up->effect, &ff_up_compat.effect, |
| 775 | sizeof(struct ff_effect_compat)); |
| 776 | memcpy(&ff_up->old, &ff_up_compat.old, |
| 777 | sizeof(struct ff_effect_compat)); |
| 778 | |
| 779 | } else { |
| 780 | if (copy_from_user(ff_up, buffer, |
| 781 | sizeof(struct uinput_ff_upload))) |
| 782 | return -EFAULT; |
| 783 | } |
| 784 | |
| 785 | return 0; |
| 786 | } |
| 787 | |
| 788 | #else |
| 789 | |
| 790 | static int uinput_ff_upload_to_user(char __user *buffer, |
| 791 | const struct uinput_ff_upload *ff_up) |
| 792 | { |
| 793 | if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload))) |
| 794 | return -EFAULT; |
| 795 | |
| 796 | return 0; |
| 797 | } |
| 798 | |
| 799 | static int uinput_ff_upload_from_user(const char __user *buffer, |
| 800 | struct uinput_ff_upload *ff_up) |
| 801 | { |
| 802 | if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload))) |
| 803 | return -EFAULT; |
| 804 | |
| 805 | return 0; |
| 806 | } |
| 807 | |
| 808 | #endif |
| 809 | |
| 810 | #define uinput_set_bit(_arg, _bit, _max) \ |
| 811 | ({ \ |
| 812 | int __ret = 0; \ |
| 813 | if (udev->state == UIST_CREATED) \ |
| 814 | __ret = -EINVAL; \ |
| 815 | else if ((_arg) > (_max)) \ |
| 816 | __ret = -EINVAL; \ |
| 817 | else set_bit((_arg), udev->dev->_bit); \ |
| 818 | __ret; \ |
| 819 | }) |
| 820 | |
| 821 | static int uinput_str_to_user(void __user *dest, const char *str, |
| 822 | unsigned int maxlen) |
| 823 | { |
| 824 | char __user *p = dest; |
| 825 | int len, ret; |
| 826 | |
| 827 | if (!str) |
| 828 | return -ENOENT; |
| 829 | |
| 830 | if (maxlen == 0) |
| 831 | return -EINVAL; |
| 832 | |
| 833 | len = strlen(str) + 1; |
| 834 | if (len > maxlen) |
| 835 | len = maxlen; |
| 836 | |
| 837 | ret = copy_to_user(p, str, len); |
| 838 | if (ret) |
| 839 | return -EFAULT; |
| 840 | |
| 841 | /* force terminating '\0' */ |
| 842 | ret = put_user(0, p + len - 1); |
| 843 | return ret ? -EFAULT : len; |
| 844 | } |
| 845 | |
| 846 | static long uinput_ioctl_handler(struct file *file, unsigned int cmd, |
| 847 | unsigned long arg, void __user *p) |
| 848 | { |
| 849 | int retval; |
| 850 | struct uinput_device *udev = file->private_data; |
| 851 | struct uinput_ff_upload ff_up; |
| 852 | struct uinput_ff_erase ff_erase; |
| 853 | struct uinput_request *req; |
| 854 | char *phys; |
| 855 | const char *name; |
| 856 | unsigned int size; |
| 857 | |
| 858 | retval = mutex_lock_interruptible(&udev->mutex); |
| 859 | if (retval) |
| 860 | return retval; |
| 861 | |
| 862 | if (!udev->dev) { |
| 863 | udev->dev = input_allocate_device(); |
| 864 | if (!udev->dev) { |
| 865 | retval = -ENOMEM; |
| 866 | goto out; |
| 867 | } |
| 868 | } |
| 869 | |
| 870 | switch (cmd) { |
| 871 | case UI_GET_VERSION: |
| 872 | if (put_user(UINPUT_VERSION, (unsigned int __user *)p)) |
| 873 | retval = -EFAULT; |
| 874 | goto out; |
| 875 | |
| 876 | case UI_DEV_CREATE: |
| 877 | retval = uinput_create_device(udev); |
| 878 | goto out; |
| 879 | |
| 880 | case UI_DEV_DESTROY: |
| 881 | uinput_destroy_device(udev); |
| 882 | goto out; |
| 883 | |
| 884 | case UI_DEV_SETUP: |
| 885 | retval = uinput_dev_setup(udev, p); |
| 886 | goto out; |
| 887 | |
| 888 | /* UI_ABS_SETUP is handled in the variable size ioctls */ |
| 889 | |
| 890 | case UI_SET_EVBIT: |
| 891 | retval = uinput_set_bit(arg, evbit, EV_MAX); |
| 892 | goto out; |
| 893 | |
| 894 | case UI_SET_KEYBIT: |
| 895 | retval = uinput_set_bit(arg, keybit, KEY_MAX); |
| 896 | goto out; |
| 897 | |
| 898 | case UI_SET_RELBIT: |
| 899 | retval = uinput_set_bit(arg, relbit, REL_MAX); |
| 900 | goto out; |
| 901 | |
| 902 | case UI_SET_ABSBIT: |
| 903 | retval = uinput_set_bit(arg, absbit, ABS_MAX); |
| 904 | goto out; |
| 905 | |
| 906 | case UI_SET_MSCBIT: |
| 907 | retval = uinput_set_bit(arg, mscbit, MSC_MAX); |
| 908 | goto out; |
| 909 | |
| 910 | case UI_SET_LEDBIT: |
| 911 | retval = uinput_set_bit(arg, ledbit, LED_MAX); |
| 912 | goto out; |
| 913 | |
| 914 | case UI_SET_SNDBIT: |
| 915 | retval = uinput_set_bit(arg, sndbit, SND_MAX); |
| 916 | goto out; |
| 917 | |
| 918 | case UI_SET_FFBIT: |
| 919 | retval = uinput_set_bit(arg, ffbit, FF_MAX); |
| 920 | goto out; |
| 921 | |
| 922 | case UI_SET_SWBIT: |
| 923 | retval = uinput_set_bit(arg, swbit, SW_MAX); |
| 924 | goto out; |
| 925 | |
| 926 | case UI_SET_PROPBIT: |
| 927 | retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX); |
| 928 | goto out; |
| 929 | |
| 930 | case UI_SET_PHYS: |
| 931 | if (udev->state == UIST_CREATED) { |
| 932 | retval = -EINVAL; |
| 933 | goto out; |
| 934 | } |
| 935 | |
| 936 | phys = strndup_user(p, 1024); |
| 937 | if (IS_ERR(phys)) { |
| 938 | retval = PTR_ERR(phys); |
| 939 | goto out; |
| 940 | } |
| 941 | |
| 942 | kfree(udev->dev->phys); |
| 943 | udev->dev->phys = phys; |
| 944 | goto out; |
| 945 | |
| 946 | case UI_BEGIN_FF_UPLOAD: |
| 947 | retval = uinput_ff_upload_from_user(p, &ff_up); |
| 948 | if (retval) |
| 949 | goto out; |
| 950 | |
| 951 | req = uinput_request_find(udev, ff_up.request_id); |
| 952 | if (!req || req->code != UI_FF_UPLOAD || |
| 953 | !req->u.upload.effect) { |
| 954 | retval = -EINVAL; |
| 955 | goto out; |
| 956 | } |
| 957 | |
| 958 | ff_up.retval = 0; |
| 959 | ff_up.effect = *req->u.upload.effect; |
| 960 | if (req->u.upload.old) |
| 961 | ff_up.old = *req->u.upload.old; |
| 962 | else |
| 963 | memset(&ff_up.old, 0, sizeof(struct ff_effect)); |
| 964 | |
| 965 | retval = uinput_ff_upload_to_user(p, &ff_up); |
| 966 | goto out; |
| 967 | |
| 968 | case UI_BEGIN_FF_ERASE: |
| 969 | if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { |
| 970 | retval = -EFAULT; |
| 971 | goto out; |
| 972 | } |
| 973 | |
| 974 | req = uinput_request_find(udev, ff_erase.request_id); |
| 975 | if (!req || req->code != UI_FF_ERASE) { |
| 976 | retval = -EINVAL; |
| 977 | goto out; |
| 978 | } |
| 979 | |
| 980 | ff_erase.retval = 0; |
| 981 | ff_erase.effect_id = req->u.effect_id; |
| 982 | if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) { |
| 983 | retval = -EFAULT; |
| 984 | goto out; |
| 985 | } |
| 986 | |
| 987 | goto out; |
| 988 | |
| 989 | case UI_END_FF_UPLOAD: |
| 990 | retval = uinput_ff_upload_from_user(p, &ff_up); |
| 991 | if (retval) |
| 992 | goto out; |
| 993 | |
| 994 | req = uinput_request_find(udev, ff_up.request_id); |
| 995 | if (!req || req->code != UI_FF_UPLOAD || |
| 996 | !req->u.upload.effect) { |
| 997 | retval = -EINVAL; |
| 998 | goto out; |
| 999 | } |
| 1000 | |
| 1001 | req->retval = ff_up.retval; |
| 1002 | complete(&req->done); |
| 1003 | goto out; |
| 1004 | |
| 1005 | case UI_END_FF_ERASE: |
| 1006 | if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { |
| 1007 | retval = -EFAULT; |
| 1008 | goto out; |
| 1009 | } |
| 1010 | |
| 1011 | req = uinput_request_find(udev, ff_erase.request_id); |
| 1012 | if (!req || req->code != UI_FF_ERASE) { |
| 1013 | retval = -EINVAL; |
| 1014 | goto out; |
| 1015 | } |
| 1016 | |
| 1017 | req->retval = ff_erase.retval; |
| 1018 | complete(&req->done); |
| 1019 | goto out; |
| 1020 | } |
| 1021 | |
| 1022 | size = _IOC_SIZE(cmd); |
| 1023 | |
| 1024 | /* Now check variable-length commands */ |
| 1025 | switch (cmd & ~IOCSIZE_MASK) { |
| 1026 | case UI_GET_SYSNAME(0): |
| 1027 | if (udev->state != UIST_CREATED) { |
| 1028 | retval = -ENOENT; |
| 1029 | goto out; |
| 1030 | } |
| 1031 | name = dev_name(&udev->dev->dev); |
| 1032 | retval = uinput_str_to_user(p, name, size); |
| 1033 | goto out; |
| 1034 | |
| 1035 | case UI_ABS_SETUP & ~IOCSIZE_MASK: |
| 1036 | retval = uinput_abs_setup(udev, p, size); |
| 1037 | goto out; |
| 1038 | } |
| 1039 | |
| 1040 | retval = -EINVAL; |
| 1041 | out: |
| 1042 | mutex_unlock(&udev->mutex); |
| 1043 | return retval; |
| 1044 | } |
| 1045 | |
| 1046 | static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
| 1047 | { |
| 1048 | return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg); |
| 1049 | } |
| 1050 | |
| 1051 | #ifdef CONFIG_COMPAT |
| 1052 | |
| 1053 | #define UI_SET_PHYS_COMPAT _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t) |
| 1054 | |
| 1055 | static long uinput_compat_ioctl(struct file *file, |
| 1056 | unsigned int cmd, unsigned long arg) |
| 1057 | { |
| 1058 | if (cmd == UI_SET_PHYS_COMPAT) |
| 1059 | cmd = UI_SET_PHYS; |
| 1060 | |
| 1061 | return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg)); |
| 1062 | } |
| 1063 | #endif |
| 1064 | |
| 1065 | static const struct file_operations uinput_fops = { |
| 1066 | .owner = THIS_MODULE, |
| 1067 | .open = uinput_open, |
| 1068 | .release = uinput_release, |
| 1069 | .read = uinput_read, |
| 1070 | .write = uinput_write, |
| 1071 | .poll = uinput_poll, |
| 1072 | .unlocked_ioctl = uinput_ioctl, |
| 1073 | #ifdef CONFIG_COMPAT |
| 1074 | .compat_ioctl = uinput_compat_ioctl, |
| 1075 | #endif |
| 1076 | .llseek = no_llseek, |
| 1077 | }; |
| 1078 | |
| 1079 | static struct miscdevice uinput_misc = { |
| 1080 | .fops = &uinput_fops, |
| 1081 | .minor = UINPUT_MINOR, |
| 1082 | .name = UINPUT_NAME, |
| 1083 | }; |
| 1084 | module_misc_device(uinput_misc); |
| 1085 | |
| 1086 | MODULE_ALIAS_MISCDEV(UINPUT_MINOR); |
| 1087 | MODULE_ALIAS("devname:" UINPUT_NAME); |
| 1088 | |
| 1089 | MODULE_AUTHOR("Aristeu Sergio Rozanski Filho"); |
| 1090 | MODULE_DESCRIPTION("User level driver support for input subsystem"); |
| 1091 | MODULE_LICENSE("GPL"); |