1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * vboxguest linux pci driver, char-dev and input-device code,
4  *
5  * Copyright (C) 2006-2016 Oracle Corporation
6  */
7 
8 #include <linux/cred.h>
9 #include <linux/input.h>
10 #include <linux/kernel.h>
11 #include <linux/miscdevice.h>
12 #include <linux/module.h>
13 #include <linux/pci.h>
14 #include <linux/poll.h>
15 #include <linux/vbox_utils.h>
16 #include "vboxguest_core.h"
17 
18 /** The device name. */
19 #define DEVICE_NAME		"vboxguest"
20 /** The device name for the device node open to everyone. */
21 #define DEVICE_NAME_USER	"vboxuser"
22 /** VirtualBox PCI vendor ID. */
23 #define VBOX_VENDORID		0x80ee
24 /** VMMDev PCI card product ID. */
25 #define VMMDEV_DEVICEID		0xcafe
26 
27 /** Mutex protecting the global vbg_gdev pointer used by vbg_get/put_gdev. */
28 static DEFINE_MUTEX(vbg_gdev_mutex);
29 /** Global vbg_gdev pointer used by vbg_get/put_gdev. */
30 static struct vbg_dev *vbg_gdev;
31 
32 static u32 vbg_misc_device_requestor(struct inode *inode)
33 {
34 	u32 requestor = VMMDEV_REQUESTOR_USERMODE |
35 			VMMDEV_REQUESTOR_CON_DONT_KNOW |
36 			VMMDEV_REQUESTOR_TRUST_NOT_GIVEN;
37 
38 	if (from_kuid(current_user_ns(), current->cred->uid) == 0)
39 		requestor |= VMMDEV_REQUESTOR_USR_ROOT;
40 	else
41 		requestor |= VMMDEV_REQUESTOR_USR_USER;
42 
43 	if (in_egroup_p(inode->i_gid))
44 		requestor |= VMMDEV_REQUESTOR_GRP_VBOX;
45 
46 	return requestor;
47 }
48 
49 static int vbg_misc_device_open(struct inode *inode, struct file *filp)
50 {
51 	struct vbg_session *session;
52 	struct vbg_dev *gdev;
53 
54 	/* misc_open sets filp->private_data to our misc device */
55 	gdev = container_of(filp->private_data, struct vbg_dev, misc_device);
56 
57 	session = vbg_core_open_session(gdev, vbg_misc_device_requestor(inode));
58 	if (IS_ERR(session))
59 		return PTR_ERR(session);
60 
61 	filp->private_data = session;
62 	return 0;
63 }
64 
65 static int vbg_misc_device_user_open(struct inode *inode, struct file *filp)
66 {
67 	struct vbg_session *session;
68 	struct vbg_dev *gdev;
69 
70 	/* misc_open sets filp->private_data to our misc device */
71 	gdev = container_of(filp->private_data, struct vbg_dev,
72 			    misc_device_user);
73 
74 	session = vbg_core_open_session(gdev, vbg_misc_device_requestor(inode) |
75 					      VMMDEV_REQUESTOR_USER_DEVICE);
76 	if (IS_ERR(session))
77 		return PTR_ERR(session);
78 
79 	filp->private_data = session;
80 	return 0;
81 }
82 
83 /**
84  * Close device.
85  * Return: 0 on success, negated errno on failure.
86  * @inode:		Pointer to inode info structure.
87  * @filp:		Associated file pointer.
88  */
89 static int vbg_misc_device_close(struct inode *inode, struct file *filp)
90 {
91 	vbg_core_close_session(filp->private_data);
92 	filp->private_data = NULL;
93 	return 0;
94 }
95 
96 /**
97  * Device I/O Control entry point.
98  * Return: 0 on success, negated errno on failure.
99  * @filp:		Associated file pointer.
100  * @req:		The request specified to ioctl().
101  * @arg:		The argument specified to ioctl().
102  */
103 static long vbg_misc_device_ioctl(struct file *filp, unsigned int req,
104 				  unsigned long arg)
105 {
106 	struct vbg_session *session = filp->private_data;
107 	size_t returned_size, size;
108 	struct vbg_ioctl_hdr hdr;
109 	bool is_vmmdev_req;
110 	int ret = 0;
111 	void *buf;
112 
113 	if (copy_from_user(&hdr, (void *)arg, sizeof(hdr)))
114 		return -EFAULT;
115 
116 	if (hdr.version != VBG_IOCTL_HDR_VERSION)
117 		return -EINVAL;
118 
119 	if (hdr.size_in < sizeof(hdr) ||
120 	    (hdr.size_out && hdr.size_out < sizeof(hdr)))
121 		return -EINVAL;
122 
123 	size = max(hdr.size_in, hdr.size_out);
124 	if (_IOC_SIZE(req) && _IOC_SIZE(req) != size)
125 		return -EINVAL;
126 	if (size > SZ_16M)
127 		return -E2BIG;
128 
129 	/*
130 	 * IOCTL_VMMDEV_REQUEST needs the buffer to be below 4G to avoid
131 	 * the need for a bounce-buffer and another copy later on.
132 	 */
133 	is_vmmdev_req = (req & ~IOCSIZE_MASK) == VBG_IOCTL_VMMDEV_REQUEST(0) ||
134 			 req == VBG_IOCTL_VMMDEV_REQUEST_BIG;
135 
136 	if (is_vmmdev_req)
137 		buf = vbg_req_alloc(size, VBG_IOCTL_HDR_TYPE_DEFAULT,
138 				    session->requestor);
139 	else
140 		buf = kmalloc(size, GFP_KERNEL);
141 	if (!buf)
142 		return -ENOMEM;
143 
144 	*((struct vbg_ioctl_hdr *)buf) = hdr;
145 	if (copy_from_user(buf + sizeof(hdr), (void *)arg + sizeof(hdr),
146 			   hdr.size_in - sizeof(hdr))) {
147 		ret = -EFAULT;
148 		goto out;
149 	}
150 	if (hdr.size_in < size)
151 		memset(buf + hdr.size_in, 0, size -  hdr.size_in);
152 
153 	ret = vbg_core_ioctl(session, req, buf);
154 	if (ret)
155 		goto out;
156 
157 	returned_size = ((struct vbg_ioctl_hdr *)buf)->size_out;
158 	if (returned_size > size) {
159 		vbg_debug("%s: too much output data %zu > %zu\n",
160 			  __func__, returned_size, size);
161 		returned_size = size;
162 	}
163 	if (copy_to_user((void *)arg, buf, returned_size) != 0)
164 		ret = -EFAULT;
165 
166 out:
167 	if (is_vmmdev_req)
168 		vbg_req_free(buf, size);
169 	else
170 		kfree(buf);
171 
172 	return ret;
173 }
174 
175 /** The file_operations structures. */
176 static const struct file_operations vbg_misc_device_fops = {
177 	.owner			= THIS_MODULE,
178 	.open			= vbg_misc_device_open,
179 	.release		= vbg_misc_device_close,
180 	.unlocked_ioctl		= vbg_misc_device_ioctl,
181 #ifdef CONFIG_COMPAT
182 	.compat_ioctl		= vbg_misc_device_ioctl,
183 #endif
184 };
185 static const struct file_operations vbg_misc_device_user_fops = {
186 	.owner			= THIS_MODULE,
187 	.open			= vbg_misc_device_user_open,
188 	.release		= vbg_misc_device_close,
189 	.unlocked_ioctl		= vbg_misc_device_ioctl,
190 #ifdef CONFIG_COMPAT
191 	.compat_ioctl		= vbg_misc_device_ioctl,
192 #endif
193 };
194 
195 /**
196  * Called when the input device is first opened.
197  *
198  * Sets up absolute mouse reporting.
199  */
200 static int vbg_input_open(struct input_dev *input)
201 {
202 	struct vbg_dev *gdev = input_get_drvdata(input);
203 	u32 feat = VMMDEV_MOUSE_GUEST_CAN_ABSOLUTE | VMMDEV_MOUSE_NEW_PROTOCOL;
204 	int ret;
205 
206 	ret = vbg_core_set_mouse_status(gdev, feat);
207 	if (ret)
208 		return ret;
209 
210 	return 0;
211 }
212 
213 /**
214  * Called if all open handles to the input device are closed.
215  *
216  * Disables absolute reporting.
217  */
218 static void vbg_input_close(struct input_dev *input)
219 {
220 	struct vbg_dev *gdev = input_get_drvdata(input);
221 
222 	vbg_core_set_mouse_status(gdev, 0);
223 }
224 
225 /**
226  * Creates the kernel input device.
227  *
228  * Return: 0 on success, negated errno on failure.
229  */
230 static int vbg_create_input_device(struct vbg_dev *gdev)
231 {
232 	struct input_dev *input;
233 
234 	input = devm_input_allocate_device(gdev->dev);
235 	if (!input)
236 		return -ENOMEM;
237 
238 	input->id.bustype = BUS_PCI;
239 	input->id.vendor = VBOX_VENDORID;
240 	input->id.product = VMMDEV_DEVICEID;
241 	input->open = vbg_input_open;
242 	input->close = vbg_input_close;
243 	input->dev.parent = gdev->dev;
244 	input->name = "VirtualBox mouse integration";
245 
246 	input_set_abs_params(input, ABS_X, VMMDEV_MOUSE_RANGE_MIN,
247 			     VMMDEV_MOUSE_RANGE_MAX, 0, 0);
248 	input_set_abs_params(input, ABS_Y, VMMDEV_MOUSE_RANGE_MIN,
249 			     VMMDEV_MOUSE_RANGE_MAX, 0, 0);
250 	input_set_capability(input, EV_KEY, BTN_MOUSE);
251 	input_set_drvdata(input, gdev);
252 
253 	gdev->input = input;
254 
255 	return input_register_device(gdev->input);
256 }
257 
258 static ssize_t host_version_show(struct device *dev,
259 				 struct device_attribute *attr, char *buf)
260 {
261 	struct vbg_dev *gdev = dev_get_drvdata(dev);
262 
263 	return sprintf(buf, "%s\n", gdev->host_version);
264 }
265 
266 static ssize_t host_features_show(struct device *dev,
267 				 struct device_attribute *attr, char *buf)
268 {
269 	struct vbg_dev *gdev = dev_get_drvdata(dev);
270 
271 	return sprintf(buf, "%#x\n", gdev->host_features);
272 }
273 
274 static DEVICE_ATTR_RO(host_version);
275 static DEVICE_ATTR_RO(host_features);
276 
277 /**
278  * Does the PCI detection and init of the device.
279  *
280  * Return: 0 on success, negated errno on failure.
281  */
282 static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
283 {
284 	struct device *dev = &pci->dev;
285 	resource_size_t io, io_len, mmio, mmio_len;
286 	struct vmmdev_memory *vmmdev;
287 	struct vbg_dev *gdev;
288 	int ret;
289 
290 	gdev = devm_kzalloc(dev, sizeof(*gdev), GFP_KERNEL);
291 	if (!gdev)
292 		return -ENOMEM;
293 
294 	ret = pci_enable_device(pci);
295 	if (ret != 0) {
296 		vbg_err("vboxguest: Error enabling device: %d\n", ret);
297 		return ret;
298 	}
299 
300 	ret = -ENODEV;
301 
302 	io = pci_resource_start(pci, 0);
303 	io_len = pci_resource_len(pci, 0);
304 	if (!io || !io_len) {
305 		vbg_err("vboxguest: Error IO-port resource (0) is missing\n");
306 		goto err_disable_pcidev;
307 	}
308 	if (devm_request_region(dev, io, io_len, DEVICE_NAME) == NULL) {
309 		vbg_err("vboxguest: Error could not claim IO resource\n");
310 		ret = -EBUSY;
311 		goto err_disable_pcidev;
312 	}
313 
314 	mmio = pci_resource_start(pci, 1);
315 	mmio_len = pci_resource_len(pci, 1);
316 	if (!mmio || !mmio_len) {
317 		vbg_err("vboxguest: Error MMIO resource (1) is missing\n");
318 		goto err_disable_pcidev;
319 	}
320 
321 	if (devm_request_mem_region(dev, mmio, mmio_len, DEVICE_NAME) == NULL) {
322 		vbg_err("vboxguest: Error could not claim MMIO resource\n");
323 		ret = -EBUSY;
324 		goto err_disable_pcidev;
325 	}
326 
327 	vmmdev = devm_ioremap(dev, mmio, mmio_len);
328 	if (!vmmdev) {
329 		vbg_err("vboxguest: Error ioremap failed; MMIO addr=%pap size=%pap\n",
330 			&mmio, &mmio_len);
331 		goto err_disable_pcidev;
332 	}
333 
334 	/* Validate MMIO region version and size. */
335 	if (vmmdev->version != VMMDEV_MEMORY_VERSION ||
336 	    vmmdev->size < 32 || vmmdev->size > mmio_len) {
337 		vbg_err("vboxguest: Bogus VMMDev memory; version=%08x (expected %08x) size=%d (expected <= %d)\n",
338 			vmmdev->version, VMMDEV_MEMORY_VERSION,
339 			vmmdev->size, (int)mmio_len);
340 		goto err_disable_pcidev;
341 	}
342 
343 	gdev->io_port = io;
344 	gdev->mmio = vmmdev;
345 	gdev->dev = dev;
346 	gdev->misc_device.minor = MISC_DYNAMIC_MINOR;
347 	gdev->misc_device.name = DEVICE_NAME;
348 	gdev->misc_device.fops = &vbg_misc_device_fops;
349 	gdev->misc_device_user.minor = MISC_DYNAMIC_MINOR;
350 	gdev->misc_device_user.name = DEVICE_NAME_USER;
351 	gdev->misc_device_user.fops = &vbg_misc_device_user_fops;
352 
353 	ret = vbg_core_init(gdev, VMMDEV_EVENT_MOUSE_POSITION_CHANGED);
354 	if (ret)
355 		goto err_disable_pcidev;
356 
357 	ret = vbg_create_input_device(gdev);
358 	if (ret) {
359 		vbg_err("vboxguest: Error creating input device: %d\n", ret);
360 		goto err_vbg_core_exit;
361 	}
362 
363 	ret = devm_request_irq(dev, pci->irq, vbg_core_isr, IRQF_SHARED,
364 			       DEVICE_NAME, gdev);
365 	if (ret) {
366 		vbg_err("vboxguest: Error requesting irq: %d\n", ret);
367 		goto err_vbg_core_exit;
368 	}
369 
370 	ret = misc_register(&gdev->misc_device);
371 	if (ret) {
372 		vbg_err("vboxguest: Error misc_register %s failed: %d\n",
373 			DEVICE_NAME, ret);
374 		goto err_vbg_core_exit;
375 	}
376 
377 	ret = misc_register(&gdev->misc_device_user);
378 	if (ret) {
379 		vbg_err("vboxguest: Error misc_register %s failed: %d\n",
380 			DEVICE_NAME_USER, ret);
381 		goto err_unregister_misc_device;
382 	}
383 
384 	mutex_lock(&vbg_gdev_mutex);
385 	if (!vbg_gdev)
386 		vbg_gdev = gdev;
387 	else
388 		ret = -EBUSY;
389 	mutex_unlock(&vbg_gdev_mutex);
390 
391 	if (ret) {
392 		vbg_err("vboxguest: Error more then 1 vbox guest pci device\n");
393 		goto err_unregister_misc_device_user;
394 	}
395 
396 	pci_set_drvdata(pci, gdev);
397 	device_create_file(dev, &dev_attr_host_version);
398 	device_create_file(dev, &dev_attr_host_features);
399 
400 	vbg_info("vboxguest: misc device minor %d, IRQ %d, I/O port %x, MMIO at %pap (size %pap)\n",
401 		 gdev->misc_device.minor, pci->irq, gdev->io_port,
402 		 &mmio, &mmio_len);
403 
404 	return 0;
405 
406 err_unregister_misc_device_user:
407 	misc_deregister(&gdev->misc_device_user);
408 err_unregister_misc_device:
409 	misc_deregister(&gdev->misc_device);
410 err_vbg_core_exit:
411 	vbg_core_exit(gdev);
412 err_disable_pcidev:
413 	pci_disable_device(pci);
414 
415 	return ret;
416 }
417 
418 static void vbg_pci_remove(struct pci_dev *pci)
419 {
420 	struct vbg_dev *gdev = pci_get_drvdata(pci);
421 
422 	mutex_lock(&vbg_gdev_mutex);
423 	vbg_gdev = NULL;
424 	mutex_unlock(&vbg_gdev_mutex);
425 
426 	device_remove_file(gdev->dev, &dev_attr_host_features);
427 	device_remove_file(gdev->dev, &dev_attr_host_version);
428 	misc_deregister(&gdev->misc_device_user);
429 	misc_deregister(&gdev->misc_device);
430 	vbg_core_exit(gdev);
431 	pci_disable_device(pci);
432 }
433 
434 struct vbg_dev *vbg_get_gdev(void)
435 {
436 	mutex_lock(&vbg_gdev_mutex);
437 
438 	/*
439 	 * Note on success we keep the mutex locked until vbg_put_gdev(),
440 	 * this stops vbg_pci_remove from removing the device from underneath
441 	 * vboxsf. vboxsf will only hold a reference for a short while.
442 	 */
443 	if (vbg_gdev)
444 		return vbg_gdev;
445 
446 	mutex_unlock(&vbg_gdev_mutex);
447 	return ERR_PTR(-ENODEV);
448 }
449 EXPORT_SYMBOL(vbg_get_gdev);
450 
451 void vbg_put_gdev(struct vbg_dev *gdev)
452 {
453 	WARN_ON(gdev != vbg_gdev);
454 	mutex_unlock(&vbg_gdev_mutex);
455 }
456 EXPORT_SYMBOL(vbg_put_gdev);
457 
458 /**
459  * Callback for mouse events.
460  *
461  * This is called at the end of the ISR, after leaving the event spinlock, if
462  * VMMDEV_EVENT_MOUSE_POSITION_CHANGED was raised by the host.
463  *
464  * @gdev:		The device extension.
465  */
466 void vbg_linux_mouse_event(struct vbg_dev *gdev)
467 {
468 	int rc;
469 
470 	/* Report events to the kernel input device */
471 	gdev->mouse_status_req->mouse_features = 0;
472 	gdev->mouse_status_req->pointer_pos_x = 0;
473 	gdev->mouse_status_req->pointer_pos_y = 0;
474 	rc = vbg_req_perform(gdev, gdev->mouse_status_req);
475 	if (rc >= 0) {
476 		input_report_abs(gdev->input, ABS_X,
477 				 gdev->mouse_status_req->pointer_pos_x);
478 		input_report_abs(gdev->input, ABS_Y,
479 				 gdev->mouse_status_req->pointer_pos_y);
480 		input_sync(gdev->input);
481 	}
482 }
483 
484 static const struct pci_device_id vbg_pci_ids[] = {
485 	{ .vendor = VBOX_VENDORID, .device = VMMDEV_DEVICEID },
486 	{}
487 };
488 MODULE_DEVICE_TABLE(pci,  vbg_pci_ids);
489 
490 static struct pci_driver vbg_pci_driver = {
491 	.name		= DEVICE_NAME,
492 	.id_table	= vbg_pci_ids,
493 	.probe		= vbg_pci_probe,
494 	.remove		= vbg_pci_remove,
495 };
496 
497 module_pci_driver(vbg_pci_driver);
498 
499 MODULE_AUTHOR("Oracle Corporation");
500 MODULE_DESCRIPTION("Oracle VM VirtualBox Guest Additions for Linux Module");
501 MODULE_LICENSE("GPL");
502