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26#include <linux/module.h>
27#include <asm/unaligned.h>
28
29#include <linux/kernel.h>
30#include <linux/init.h>
31#include <linux/slab.h>
32#include <linux/types.h>
33#include <linux/errno.h>
34#include <linux/sched.h>
35#include <linux/poll.h>
36
37#include <linux/skbuff.h>
38#include <linux/miscdevice.h>
39
40#include <net/bluetooth/bluetooth.h>
41#include <net/bluetooth/hci_core.h>
42
43#define VERSION "1.5"
44
45static bool amp;
46
47struct vhci_data {
48 struct hci_dev *hdev;
49
50 wait_queue_head_t read_wait;
51 struct sk_buff_head readq;
52
53 struct delayed_work open_timeout;
54};
55
56static int vhci_open_dev(struct hci_dev *hdev)
57{
58 return 0;
59}
60
61static int vhci_close_dev(struct hci_dev *hdev)
62{
63 struct vhci_data *data = hci_get_drvdata(hdev);
64
65 skb_queue_purge(&data->readq);
66
67 return 0;
68}
69
70static int vhci_flush(struct hci_dev *hdev)
71{
72 struct vhci_data *data = hci_get_drvdata(hdev);
73
74 skb_queue_purge(&data->readq);
75
76 return 0;
77}
78
79static int vhci_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
80{
81 struct vhci_data *data = hci_get_drvdata(hdev);
82
83 memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
84 skb_queue_tail(&data->readq, skb);
85
86 wake_up_interruptible(&data->read_wait);
87 return 0;
88}
89
90static int vhci_create_device(struct vhci_data *data, __u8 opcode)
91{
92 struct hci_dev *hdev;
93 struct sk_buff *skb;
94 __u8 dev_type;
95
96
97 dev_type = opcode & 0x03;
98
99 if (dev_type != HCI_BREDR && dev_type != HCI_AMP)
100 return -EINVAL;
101
102
103 if (opcode & 0x3c)
104 return -EINVAL;
105
106 skb = bt_skb_alloc(4, GFP_KERNEL);
107 if (!skb)
108 return -ENOMEM;
109
110 hdev = hci_alloc_dev();
111 if (!hdev) {
112 kfree_skb(skb);
113 return -ENOMEM;
114 }
115
116 data->hdev = hdev;
117
118 hdev->bus = HCI_VIRTUAL;
119 hdev->dev_type = dev_type;
120 hci_set_drvdata(hdev, data);
121
122 hdev->open = vhci_open_dev;
123 hdev->close = vhci_close_dev;
124 hdev->flush = vhci_flush;
125 hdev->send = vhci_send_frame;
126
127
128 if (opcode & 0x40)
129 set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
130
131
132 if (opcode & 0x80)
133 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
134
135 if (hci_register_dev(hdev) < 0) {
136 BT_ERR("Can't register HCI device");
137 hci_free_dev(hdev);
138 data->hdev = NULL;
139 kfree_skb(skb);
140 return -EBUSY;
141 }
142
143 hci_skb_pkt_type(skb) = HCI_VENDOR_PKT;
144
145 *skb_put(skb, 1) = 0xff;
146 *skb_put(skb, 1) = opcode;
147 put_unaligned_le16(hdev->id, skb_put(skb, 2));
148 skb_queue_tail(&data->readq, skb);
149
150 wake_up_interruptible(&data->read_wait);
151 return 0;
152}
153
154static inline ssize_t vhci_get_user(struct vhci_data *data,
155 struct iov_iter *from)
156{
157 size_t len = iov_iter_count(from);
158 struct sk_buff *skb;
159 __u8 pkt_type, opcode;
160 int ret;
161
162 if (len < 2 || len > HCI_MAX_FRAME_SIZE)
163 return -EINVAL;
164
165 skb = bt_skb_alloc(len, GFP_KERNEL);
166 if (!skb)
167 return -ENOMEM;
168
169 if (copy_from_iter(skb_put(skb, len), len, from) != len) {
170 kfree_skb(skb);
171 return -EFAULT;
172 }
173
174 pkt_type = *((__u8 *) skb->data);
175 skb_pull(skb, 1);
176
177 switch (pkt_type) {
178 case HCI_EVENT_PKT:
179 case HCI_ACLDATA_PKT:
180 case HCI_SCODATA_PKT:
181 if (!data->hdev) {
182 kfree_skb(skb);
183 return -ENODEV;
184 }
185
186 hci_skb_pkt_type(skb) = pkt_type;
187
188 ret = hci_recv_frame(data->hdev, skb);
189 break;
190
191 case HCI_VENDOR_PKT:
192 if (data->hdev) {
193 kfree_skb(skb);
194 return -EBADFD;
195 }
196
197 cancel_delayed_work_sync(&data->open_timeout);
198
199 opcode = *((__u8 *) skb->data);
200 skb_pull(skb, 1);
201
202 if (skb->len > 0) {
203 kfree_skb(skb);
204 return -EINVAL;
205 }
206
207 kfree_skb(skb);
208
209 ret = vhci_create_device(data, opcode);
210 break;
211
212 default:
213 kfree_skb(skb);
214 return -EINVAL;
215 }
216
217 return (ret < 0) ? ret : len;
218}
219
220static inline ssize_t vhci_put_user(struct vhci_data *data,
221 struct sk_buff *skb,
222 char __user *buf, int count)
223{
224 char __user *ptr = buf;
225 int len;
226
227 len = min_t(unsigned int, skb->len, count);
228
229 if (copy_to_user(ptr, skb->data, len))
230 return -EFAULT;
231
232 if (!data->hdev)
233 return len;
234
235 data->hdev->stat.byte_tx += len;
236
237 switch (hci_skb_pkt_type(skb)) {
238 case HCI_COMMAND_PKT:
239 data->hdev->stat.cmd_tx++;
240 break;
241 case HCI_ACLDATA_PKT:
242 data->hdev->stat.acl_tx++;
243 break;
244 case HCI_SCODATA_PKT:
245 data->hdev->stat.sco_tx++;
246 break;
247 }
248
249 return len;
250}
251
252static ssize_t vhci_read(struct file *file,
253 char __user *buf, size_t count, loff_t *pos)
254{
255 struct vhci_data *data = file->private_data;
256 struct sk_buff *skb;
257 ssize_t ret = 0;
258
259 while (count) {
260 skb = skb_dequeue(&data->readq);
261 if (skb) {
262 ret = vhci_put_user(data, skb, buf, count);
263 if (ret < 0)
264 skb_queue_head(&data->readq, skb);
265 else
266 kfree_skb(skb);
267 break;
268 }
269
270 if (file->f_flags & O_NONBLOCK) {
271 ret = -EAGAIN;
272 break;
273 }
274
275 ret = wait_event_interruptible(data->read_wait,
276 !skb_queue_empty(&data->readq));
277 if (ret < 0)
278 break;
279 }
280
281 return ret;
282}
283
284static ssize_t vhci_write(struct kiocb *iocb, struct iov_iter *from)
285{
286 struct file *file = iocb->ki_filp;
287 struct vhci_data *data = file->private_data;
288
289 return vhci_get_user(data, from);
290}
291
292static unsigned int vhci_poll(struct file *file, poll_table *wait)
293{
294 struct vhci_data *data = file->private_data;
295
296 poll_wait(file, &data->read_wait, wait);
297
298 if (!skb_queue_empty(&data->readq))
299 return POLLIN | POLLRDNORM;
300
301 return POLLOUT | POLLWRNORM;
302}
303
304static void vhci_open_timeout(struct work_struct *work)
305{
306 struct vhci_data *data = container_of(work, struct vhci_data,
307 open_timeout.work);
308
309 vhci_create_device(data, amp ? HCI_AMP : HCI_BREDR);
310}
311
312static int vhci_open(struct inode *inode, struct file *file)
313{
314 struct vhci_data *data;
315
316 data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL);
317 if (!data)
318 return -ENOMEM;
319
320 skb_queue_head_init(&data->readq);
321 init_waitqueue_head(&data->read_wait);
322
323 INIT_DELAYED_WORK(&data->open_timeout, vhci_open_timeout);
324
325 file->private_data = data;
326 nonseekable_open(inode, file);
327
328 schedule_delayed_work(&data->open_timeout, msecs_to_jiffies(1000));
329
330 return 0;
331}
332
333static int vhci_release(struct inode *inode, struct file *file)
334{
335 struct vhci_data *data = file->private_data;
336 struct hci_dev *hdev = data->hdev;
337
338 cancel_delayed_work_sync(&data->open_timeout);
339
340 if (hdev) {
341 hci_unregister_dev(hdev);
342 hci_free_dev(hdev);
343 }
344
345 file->private_data = NULL;
346 kfree(data);
347
348 return 0;
349}
350
351static const struct file_operations vhci_fops = {
352 .owner = THIS_MODULE,
353 .read = vhci_read,
354 .write_iter = vhci_write,
355 .poll = vhci_poll,
356 .open = vhci_open,
357 .release = vhci_release,
358 .llseek = no_llseek,
359};
360
361static struct miscdevice vhci_miscdev = {
362 .name = "vhci",
363 .fops = &vhci_fops,
364 .minor = VHCI_MINOR,
365};
366
367static int __init vhci_init(void)
368{
369 BT_INFO("Virtual HCI driver ver %s", VERSION);
370
371 return misc_register(&vhci_miscdev);
372}
373
374static void __exit vhci_exit(void)
375{
376 misc_deregister(&vhci_miscdev);
377}
378
379module_init(vhci_init);
380module_exit(vhci_exit);
381
382module_param(amp, bool, 0644);
383MODULE_PARM_DESC(amp, "Create AMP controller device");
384
385MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
386MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
387MODULE_VERSION(VERSION);
388MODULE_LICENSE("GPL");
389MODULE_ALIAS("devname:vhci");
390MODULE_ALIAS_MISCDEV(VHCI_MINOR);
391
