aboutsummaryrefslogtreecommitdiffstats
path: root/net/bluetooth/a2mp.c
blob: fb93250b3938600e820eb8927049707532fc3871 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
/*
   Copyright (c) 2010,2011 Code Aurora Forum.  All rights reserved.
   Copyright (c) 2011,2012 Intel Corp.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License version 2 and
   only version 2 as published by the Free Software Foundation.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
*/

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/l2cap.h>
#include <net/bluetooth/a2mp.h>

/* A2MP build & send command helper functions */
static struct a2mp_cmd *__a2mp_build(u8 code, u8 ident, u16 len, void *data)
{
	struct a2mp_cmd *cmd;
	int plen;

	plen = sizeof(*cmd) + len;
	cmd = kzalloc(plen, GFP_KERNEL);
	if (!cmd)
		return NULL;

	cmd->code = code;
	cmd->ident = ident;
	cmd->len = cpu_to_le16(len);

	memcpy(cmd->data, data, len);

	return cmd;
}

static void a2mp_send(struct amp_mgr *mgr, u8 code, u8 ident, u16 len,
		      void *data)
{
	struct l2cap_chan *chan = mgr->a2mp_chan;
	struct a2mp_cmd *cmd;
	u16 total_len = len + sizeof(*cmd);
	struct kvec iv;
	struct msghdr msg;

	cmd = __a2mp_build(code, ident, len, data);
	if (!cmd)
		return;

	iv.iov_base = cmd;
	iv.iov_len = total_len;

	memset(&msg, 0, sizeof(msg));

	msg.msg_iov = (struct iovec *) &iv;
	msg.msg_iovlen = 1;

	l2cap_chan_send(chan, &msg, total_len, 0);

	kfree(cmd);
}

static inline void __a2mp_cl_bredr(struct a2mp_cl *cl)
{
	cl->id = 0;
	cl->type = 0;
	cl->status = 1;
}

/* hci_dev_list shall be locked */
static void __a2mp_add_cl(struct amp_mgr *mgr, struct a2mp_cl *cl, u8 num_ctrl)
{
	int i = 0;
	struct hci_dev *hdev;

	__a2mp_cl_bredr(cl);

	list_for_each_entry(hdev, &hci_dev_list, list) {
		/* Iterate through AMP controllers */
		if (hdev->id == HCI_BREDR_ID)
			continue;

		/* Starting from second entry */
		if (++i >= num_ctrl)
			return;

		cl[i].id = hdev->id;
		cl[i].type = hdev->amp_type;
		cl[i].status = hdev->amp_status;
	}
}

/* Processing A2MP messages */
static int a2mp_command_rej(struct amp_mgr *mgr, struct sk_buff *skb,
			    struct a2mp_cmd *hdr)
{
	struct a2mp_cmd_rej *rej = (void *) skb->data;

	if (le16_to_cpu(hdr->len) < sizeof(*rej))
		return -EINVAL;

	BT_DBG("ident %d reason %d", hdr->ident, le16_to_cpu(rej->reason));

	skb_pull(skb, sizeof(*rej));

	return 0;
}

static int a2mp_discover_req(struct amp_mgr *mgr, struct sk_buff *skb,
			     struct a2mp_cmd *hdr)
{
	struct a2mp_discov_req *req = (void *) skb->data;
	u16 len = le16_to_cpu(hdr->len);
	struct a2mp_discov_rsp *rsp;
	u16 ext_feat;
	u8 num_ctrl;

	if (len < sizeof(*req))
		return -EINVAL;

	skb_pull(skb, sizeof(*req));

	ext_feat = le16_to_cpu(req->ext_feat);

	BT_DBG("mtu %d efm 0x%4.4x", le16_to_cpu(req->mtu), ext_feat);

	/* check that packet is not broken for now */
	while (ext_feat & A2MP_FEAT_EXT) {
		if (len < sizeof(ext_feat))
			return -EINVAL;

		ext_feat = get_unaligned_le16(skb->data);
		BT_DBG("efm 0x%4.4x", ext_feat);
		len -= sizeof(ext_feat);
		skb_pull(skb, sizeof(ext_feat));
	}

	read_lock(&hci_dev_list_lock);

	num_ctrl = __hci_num_ctrl();
	len = num_ctrl * sizeof(struct a2mp_cl) + sizeof(*rsp);
	rsp = kmalloc(len, GFP_ATOMIC);
	if (!rsp) {
		read_unlock(&hci_dev_list_lock);
		return -ENOMEM;
	}

	rsp->mtu = __constant_cpu_to_le16(L2CAP_A2MP_DEFAULT_MTU);
	rsp->ext_feat = 0;

	__a2mp_add_cl(mgr, rsp->cl, num_ctrl);

	read_unlock(&hci_dev_list_lock);

	a2mp_send(mgr, A2MP_DISCOVER_RSP, hdr->ident, len, rsp);

	kfree(rsp);
	return 0;
}

static int a2mp_change_notify(struct amp_mgr *mgr, struct sk_buff *skb,
			      struct a2mp_cmd *hdr)
{
	struct a2mp_cl *cl = (void *) skb->data;

	while (skb->len >= sizeof(*cl)) {
		BT_DBG("Controller id %d type %d status %d", cl->id, cl->type,
		       cl->status);
		cl = (struct a2mp_cl *) skb_pull(skb, sizeof(*cl));
	}

	/* TODO send A2MP_CHANGE_RSP */

	return 0;
}

static int a2mp_getinfo_req(struct amp_mgr *mgr, struct sk_buff *skb,
			    struct a2mp_cmd *hdr)
{
	struct a2mp_info_req *req  = (void *) skb->data;
	struct a2mp_info_rsp rsp;
	struct hci_dev *hdev;

	if (le16_to_cpu(hdr->len) < sizeof(*req))
		return -EINVAL;

	BT_DBG("id %d", req->id);

	rsp.id = req->id;
	rsp.status = A2MP_STATUS_INVALID_CTRL_ID;

	hdev = hci_dev_get(req->id);
	if (hdev && hdev->amp_type != HCI_BREDR) {
		rsp.status = 0;
		rsp.total_bw = cpu_to_le32(hdev->amp_total_bw);
		rsp.max_bw = cpu_to_le32(hdev->amp_max_bw);
		rsp.min_latency = cpu_to_le32(hdev->amp_min_latency);
		rsp.pal_cap = cpu_to_le16(hdev->amp_pal_cap);
		rsp.assoc_size = cpu_to_le16(hdev->amp_assoc_size);
	}

	if (hdev)
		hci_dev_put(hdev);

	a2mp_send(mgr, A2MP_GETINFO_RSP, hdr->ident, sizeof(rsp), &rsp);

	skb_pull(skb, sizeof(*req));
	return 0;
}

static int a2mp_getampassoc_req(struct amp_mgr *mgr, struct sk_buff *skb,
				struct a2mp_cmd *hdr)
{
	struct a2mp_amp_assoc_req *req = (void *) skb->data;
	struct hci_dev *hdev;

	if (le16_to_cpu(hdr->len) < sizeof(*req))
		return -EINVAL;

	BT_DBG("id %d", req->id);

	hdev = hci_dev_get(req->id);
	if (!hdev || hdev->amp_type == HCI_BREDR) {
		struct a2mp_amp_assoc_rsp rsp;
		rsp.id = req->id;
		rsp.status = A2MP_STATUS_INVALID_CTRL_ID;

		a2mp_send(mgr, A2MP_GETAMPASSOC_RSP, hdr->ident, sizeof(rsp),
			  &rsp);
		goto clean;
	}

	/* Placeholder for HCI Read AMP Assoc */

clean:
	if (hdev)
		hci_dev_put(hdev);

	skb_pull(skb, sizeof(*req));
	return 0;
}

static int a2mp_createphyslink_req(struct amp_mgr *mgr, struct sk_buff *skb,
				   struct a2mp_cmd *hdr)
{
	struct a2mp_physlink_req *req = (void *) skb->data;

	struct a2mp_physlink_rsp rsp;
	struct hci_dev *hdev;

	if (le16_to_cpu(hdr->len) < sizeof(*req))
		return -EINVAL;

	BT_DBG("local_id %d, remote_id %d", req->local_id, req->remote_id);

	rsp.local_id = req->remote_id;
	rsp.remote_id = req->local_id;

	hdev = hci_dev_get(req->remote_id);
	if (!hdev || hdev->amp_type != HCI_AMP) {
		rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
		goto send_rsp;
	}

	/* TODO process physlink create */

	rsp.status = A2MP_STATUS_SUCCESS;

send_rsp:
	if (hdev)
		hci_dev_put(hdev);

	a2mp_send(mgr, A2MP_CREATEPHYSLINK_RSP, hdr->ident, sizeof(rsp),
		  &rsp);

	skb_pull(skb, le16_to_cpu(hdr->len));
	return 0;
}

static int a2mp_discphyslink_req(struct amp_mgr *mgr, struct sk_buff *skb,
				 struct a2mp_cmd *hdr)
{
	struct a2mp_physlink_req *req = (void *) skb->data;
	struct a2mp_physlink_rsp rsp;
	struct hci_dev *hdev;

	if (le16_to_cpu(hdr->len) < sizeof(*req))
		return -EINVAL;

	BT_DBG("local_id %d remote_id %d", req->local_id, req->remote_id);

	rsp.local_id = req->remote_id;
	rsp.remote_id = req->local_id;
	rsp.status = A2MP_STATUS_SUCCESS;

	hdev = hci_dev_get(req->local_id);
	if (!hdev) {
		rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
		goto send_rsp;
	}

	/* TODO Disconnect Phys Link here */

	hci_dev_put(hdev);

send_rsp:
	a2mp_send(mgr, A2MP_DISCONNPHYSLINK_RSP, hdr->ident, sizeof(rsp), &rsp);

	skb_pull(skb, sizeof(*req));
	return 0;
}

static inline int a2mp_cmd_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
			       struct a2mp_cmd *hdr)
{
	BT_DBG("ident %d code %d", hdr->ident, hdr->code);

	skb_pull(skb, le16_to_cpu(hdr->len));
	return 0;
}

/* Handle A2MP signalling */
static int a2mp_chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
{
	struct a2mp_cmd *hdr = (void *) skb->data;
	struct amp_mgr *mgr = chan->data;
	int err = 0;

	amp_mgr_get(mgr);

	while (skb->len >= sizeof(*hdr)) {
		struct a2mp_cmd *hdr = (void *) skb->data;
		u16 len = le16_to_cpu(hdr->len);

		BT_DBG("code 0x%02x id %d len %d", hdr->code, hdr->ident, len);

		skb_pull(skb, sizeof(*hdr));

		if (len > skb->len || !hdr->ident) {
			err = -EINVAL;
			break;
		}

		mgr->ident = hdr->ident;

		switch (hdr->code) {
		case A2MP_COMMAND_REJ:
			a2mp_command_rej(mgr, skb, hdr);
			break;

		case A2MP_DISCOVER_REQ:
			err = a2mp_discover_req(mgr, skb, hdr);
			break;

		case A2MP_CHANGE_NOTIFY:
			err = a2mp_change_notify(mgr, skb, hdr);
			break;

		case A2MP_GETINFO_REQ:
			err = a2mp_getinfo_req(mgr, skb, hdr);
			break;

		case A2MP_GETAMPASSOC_REQ:
			err = a2mp_getampassoc_req(mgr, skb, hdr);
			break;

		case A2MP_CREATEPHYSLINK_REQ:
			err = a2mp_createphyslink_req(mgr, skb, hdr);
			break;

		case A2MP_DISCONNPHYSLINK_REQ:
			err = a2mp_discphyslink_req(mgr, skb, hdr);
			break;

		case A2MP_CHANGE_RSP:
		case A2MP_DISCOVER_RSP:
		case A2MP_GETINFO_RSP:
		case A2MP_GETAMPASSOC_RSP:
		case A2MP_CREATEPHYSLINK_RSP:
		case A2MP_DISCONNPHYSLINK_RSP:
			err = a2mp_cmd_rsp(mgr, skb, hdr);
			break;

		default:
			BT_ERR("Unknown A2MP sig cmd 0x%2.2x", hdr->code);
			err = -EINVAL;
			break;
		}
	}

	if (err) {
		struct a2mp_cmd_rej rej;
		rej.reason = __constant_cpu_to_le16(0);

		BT_DBG("Send A2MP Rej: cmd 0x%2.2x err %d", hdr->code, err);

		a2mp_send(mgr, A2MP_COMMAND_REJ, hdr->ident, sizeof(rej),
			  &rej);
	}

	/* Always free skb and return success error code to prevent
	   from sending L2CAP Disconnect over A2MP channel */
	kfree_skb(skb);

	amp_mgr_put(mgr);

	return 0;
}

static void a2mp_chan_close_cb(struct l2cap_chan *chan)
{
	l2cap_chan_destroy(chan);
}

static void a2mp_chan_state_change_cb(struct l2cap_chan *chan, int state)
{
	struct amp_mgr *mgr = chan->data;

	if (!mgr)
		return;

	BT_DBG("chan %p state %s", chan, state_to_string(state));

	chan->state = state;

	switch (state) {
	case BT_CLOSED:
		if (mgr)
			amp_mgr_put(mgr);
		break;
	}
}

static struct sk_buff *a2mp_chan_alloc_skb_cb(struct l2cap_chan *chan,
					      unsigned long len, int nb)
{
	return bt_skb_alloc(len, GFP_KERNEL);
}

static struct l2cap_ops a2mp_chan_ops = {
	.name = "L2CAP A2MP channel",
	.recv = a2mp_chan_recv_cb,
	.close = a2mp_chan_close_cb,
	.state_change = a2mp_chan_state_change_cb,
	.alloc_skb = a2mp_chan_alloc_skb_cb,

	/* Not implemented for A2MP */
	.new_connection = l2cap_chan_no_new_connection,
	.teardown = l2cap_chan_no_teardown,
	.ready = l2cap_chan_no_ready,
};

static struct l2cap_chan *a2mp_chan_open(struct l2cap_conn *conn)
{
	struct l2cap_chan *chan;
	int err;

	chan = l2cap_chan_create();
	if (!chan)
		return NULL;

	BT_DBG("chan %p", chan);

	chan->chan_type = L2CAP_CHAN_CONN_FIX_A2MP;
	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;

	chan->ops = &a2mp_chan_ops;

	l2cap_chan_set_defaults(chan);
	chan->remote_max_tx = chan->max_tx;
	chan->remote_tx_win = chan->tx_win;

	chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
	chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;

	skb_queue_head_init(&chan->tx_q);

	chan->mode = L2CAP_MODE_ERTM;

	err = l2cap_ertm_init(chan);
	if (err < 0) {
		l2cap_chan_del(chan, 0);
		return NULL;
	}

	chan->conf_state = 0;

	l2cap_chan_add(conn, chan);

	chan->remote_mps = chan->omtu;
	chan->mps = chan->omtu;

	chan->state = BT_CONNECTED;

	return chan;
}

/* AMP Manager functions */
void amp_mgr_get(struct amp_mgr *mgr)
{
	BT_DBG("mgr %p", mgr);

	kref_get(&mgr->kref);
}

static void amp_mgr_destroy(struct kref *kref)
{
	struct amp_mgr *mgr = container_of(kref, struct amp_mgr, kref);

	BT_DBG("mgr %p", mgr);

	kfree(mgr);
}

int amp_mgr_put(struct amp_mgr *mgr)
{
	BT_DBG("mgr %p", mgr);

	return kref_put(&mgr->kref, &amp_mgr_destroy);
}

static struct amp_mgr *amp_mgr_create(struct l2cap_conn *conn)
{
	struct amp_mgr *mgr;
	struct l2cap_chan *chan;

	mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
	if (!mgr)
		return NULL;

	BT_DBG("conn %p mgr %p", conn, mgr);

	mgr->l2cap_conn = conn;

	chan = a2mp_chan_open(conn);
	if (!chan) {
		kfree(mgr);
		return NULL;
	}

	mgr->a2mp_chan = chan;
	chan->data = mgr;

	conn->hcon->amp_mgr = mgr;

	kref_init(&mgr->kref);

	return mgr;
}

struct l2cap_chan *a2mp_channel_create(struct l2cap_conn *conn,
				       struct sk_buff *skb)
{
	struct amp_mgr *mgr;

	mgr = amp_mgr_create(conn);
	if (!mgr) {
		BT_ERR("Could not create AMP manager");
		return NULL;
	}

	BT_DBG("mgr: %p chan %p", mgr, mgr->a2mp_chan);

	return mgr->a2mp_chan;
}