Merge remote-tracking branch 'stable/linux-4.19.y' into rpi-4.19.y
[platform/kernel/linux-rpi.git] / net / bluetooth / hci_conn.c
1 /*
2    BlueZ - Bluetooth protocol stack for Linux
3    Copyright (c) 2000-2001, 2010, Code Aurora Forum. All rights reserved.
4
5    Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
6
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License version 2 as
9    published by the Free Software Foundation;
10
11    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
12    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
13    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
14    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
15    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
16    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19
20    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
21    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
22    SOFTWARE IS DISCLAIMED.
23 */
24
25 /* Bluetooth HCI connection handling. */
26
27 #include <linux/export.h>
28 #include <linux/debugfs.h>
29
30 #include <net/bluetooth/bluetooth.h>
31 #include <net/bluetooth/hci_core.h>
32 #include <net/bluetooth/l2cap.h>
33
34 #include "hci_request.h"
35 #include "smp.h"
36 #include "a2mp.h"
37
38 struct sco_param {
39         u16 pkt_type;
40         u16 max_latency;
41         u8  retrans_effort;
42 };
43
44 static const struct sco_param esco_param_cvsd[] = {
45         { EDR_ESCO_MASK & ~ESCO_2EV3, 0x000a,   0x01 }, /* S3 */
46         { EDR_ESCO_MASK & ~ESCO_2EV3, 0x0007,   0x01 }, /* S2 */
47         { EDR_ESCO_MASK | ESCO_EV3,   0x0007,   0x01 }, /* S1 */
48         { EDR_ESCO_MASK | ESCO_HV3,   0xffff,   0x01 }, /* D1 */
49         { EDR_ESCO_MASK | ESCO_HV1,   0xffff,   0x01 }, /* D0 */
50 };
51
52 static const struct sco_param sco_param_cvsd[] = {
53         { EDR_ESCO_MASK | ESCO_HV3,   0xffff,   0xff }, /* D1 */
54         { EDR_ESCO_MASK | ESCO_HV1,   0xffff,   0xff }, /* D0 */
55 };
56
57 static const struct sco_param esco_param_msbc[] = {
58         { EDR_ESCO_MASK & ~ESCO_2EV3, 0x000d,   0x02 }, /* T2 */
59         { EDR_ESCO_MASK | ESCO_EV3,   0x0008,   0x02 }, /* T1 */
60 };
61
62 /* This function requires the caller holds hdev->lock */
63 static void hci_connect_le_scan_cleanup(struct hci_conn *conn)
64 {
65         struct hci_conn_params *params;
66         struct hci_dev *hdev = conn->hdev;
67         struct smp_irk *irk;
68         bdaddr_t *bdaddr;
69         u8 bdaddr_type;
70
71         bdaddr = &conn->dst;
72         bdaddr_type = conn->dst_type;
73
74         /* Check if we need to convert to identity address */
75         irk = hci_get_irk(hdev, bdaddr, bdaddr_type);
76         if (irk) {
77                 bdaddr = &irk->bdaddr;
78                 bdaddr_type = irk->addr_type;
79         }
80
81         params = hci_pend_le_action_lookup(&hdev->pend_le_conns, bdaddr,
82                                            bdaddr_type);
83         if (!params || !params->explicit_connect)
84                 return;
85
86         /* The connection attempt was doing scan for new RPA, and is
87          * in scan phase. If params are not associated with any other
88          * autoconnect action, remove them completely. If they are, just unmark
89          * them as waiting for connection, by clearing explicit_connect field.
90          */
91         params->explicit_connect = false;
92
93         list_del_init(&params->action);
94
95         switch (params->auto_connect) {
96         case HCI_AUTO_CONN_EXPLICIT:
97                 hci_conn_params_del(hdev, bdaddr, bdaddr_type);
98                 /* return instead of break to avoid duplicate scan update */
99                 return;
100         case HCI_AUTO_CONN_DIRECT:
101         case HCI_AUTO_CONN_ALWAYS:
102                 list_add(&params->action, &hdev->pend_le_conns);
103                 break;
104         case HCI_AUTO_CONN_REPORT:
105                 list_add(&params->action, &hdev->pend_le_reports);
106                 break;
107         default:
108                 break;
109         }
110
111         hci_update_background_scan(hdev);
112 }
113
114 static void hci_conn_cleanup(struct hci_conn *conn)
115 {
116         struct hci_dev *hdev = conn->hdev;
117
118         if (test_bit(HCI_CONN_PARAM_REMOVAL_PEND, &conn->flags))
119                 hci_conn_params_del(conn->hdev, &conn->dst, conn->dst_type);
120
121         hci_chan_list_flush(conn);
122
123         hci_conn_hash_del(hdev, conn);
124
125         if (hdev->notify)
126                 hdev->notify(hdev, HCI_NOTIFY_CONN_DEL);
127
128         hci_conn_del_sysfs(conn);
129
130         debugfs_remove_recursive(conn->debugfs);
131
132         hci_dev_put(hdev);
133
134         hci_conn_put(conn);
135 }
136
137 static void le_scan_cleanup(struct work_struct *work)
138 {
139         struct hci_conn *conn = container_of(work, struct hci_conn,
140                                              le_scan_cleanup);
141         struct hci_dev *hdev = conn->hdev;
142         struct hci_conn *c = NULL;
143
144         BT_DBG("%s hcon %p", hdev->name, conn);
145
146         hci_dev_lock(hdev);
147
148         /* Check that the hci_conn is still around */
149         rcu_read_lock();
150         list_for_each_entry_rcu(c, &hdev->conn_hash.list, list) {
151                 if (c == conn)
152                         break;
153         }
154         rcu_read_unlock();
155
156         if (c == conn) {
157                 hci_connect_le_scan_cleanup(conn);
158                 hci_conn_cleanup(conn);
159         }
160
161         hci_dev_unlock(hdev);
162         hci_dev_put(hdev);
163         hci_conn_put(conn);
164 }
165
166 static void hci_connect_le_scan_remove(struct hci_conn *conn)
167 {
168         BT_DBG("%s hcon %p", conn->hdev->name, conn);
169
170         /* We can't call hci_conn_del/hci_conn_cleanup here since that
171          * could deadlock with another hci_conn_del() call that's holding
172          * hci_dev_lock and doing cancel_delayed_work_sync(&conn->disc_work).
173          * Instead, grab temporary extra references to the hci_dev and
174          * hci_conn and perform the necessary cleanup in a separate work
175          * callback.
176          */
177
178         hci_dev_hold(conn->hdev);
179         hci_conn_get(conn);
180
181         /* Even though we hold a reference to the hdev, many other
182          * things might get cleaned up meanwhile, including the hdev's
183          * own workqueue, so we can't use that for scheduling.
184          */
185         schedule_work(&conn->le_scan_cleanup);
186 }
187
188 static void hci_acl_create_connection(struct hci_conn *conn)
189 {
190         struct hci_dev *hdev = conn->hdev;
191         struct inquiry_entry *ie;
192         struct hci_cp_create_conn cp;
193
194         BT_DBG("hcon %p", conn);
195
196         conn->state = BT_CONNECT;
197         conn->out = true;
198         conn->role = HCI_ROLE_MASTER;
199
200         conn->attempt++;
201
202         conn->link_policy = hdev->link_policy;
203
204         memset(&cp, 0, sizeof(cp));
205         bacpy(&cp.bdaddr, &conn->dst);
206         cp.pscan_rep_mode = 0x02;
207
208         ie = hci_inquiry_cache_lookup(hdev, &conn->dst);
209         if (ie) {
210                 if (inquiry_entry_age(ie) <= INQUIRY_ENTRY_AGE_MAX) {
211                         cp.pscan_rep_mode = ie->data.pscan_rep_mode;
212                         cp.pscan_mode     = ie->data.pscan_mode;
213                         cp.clock_offset   = ie->data.clock_offset |
214                                             cpu_to_le16(0x8000);
215                 }
216
217                 memcpy(conn->dev_class, ie->data.dev_class, 3);
218                 if (ie->data.ssp_mode > 0)
219                         set_bit(HCI_CONN_SSP_ENABLED, &conn->flags);
220         }
221
222         cp.pkt_type = cpu_to_le16(conn->pkt_type);
223         if (lmp_rswitch_capable(hdev) && !(hdev->link_mode & HCI_LM_MASTER))
224                 cp.role_switch = 0x01;
225         else
226                 cp.role_switch = 0x00;
227
228         hci_send_cmd(hdev, HCI_OP_CREATE_CONN, sizeof(cp), &cp);
229 }
230
231 int hci_disconnect(struct hci_conn *conn, __u8 reason)
232 {
233         BT_DBG("hcon %p", conn);
234
235         /* When we are master of an established connection and it enters
236          * the disconnect timeout, then go ahead and try to read the
237          * current clock offset.  Processing of the result is done
238          * within the event handling and hci_clock_offset_evt function.
239          */
240         if (conn->type == ACL_LINK && conn->role == HCI_ROLE_MASTER &&
241             (conn->state == BT_CONNECTED || conn->state == BT_CONFIG)) {
242                 struct hci_dev *hdev = conn->hdev;
243                 struct hci_cp_read_clock_offset clkoff_cp;
244
245                 clkoff_cp.handle = cpu_to_le16(conn->handle);
246                 hci_send_cmd(hdev, HCI_OP_READ_CLOCK_OFFSET, sizeof(clkoff_cp),
247                              &clkoff_cp);
248         }
249
250         return hci_abort_conn(conn, reason);
251 }
252
253 static void hci_add_sco(struct hci_conn *conn, __u16 handle)
254 {
255         struct hci_dev *hdev = conn->hdev;
256         struct hci_cp_add_sco cp;
257
258         BT_DBG("hcon %p", conn);
259
260         conn->state = BT_CONNECT;
261         conn->out = true;
262
263         conn->attempt++;
264
265         cp.handle   = cpu_to_le16(handle);
266         cp.pkt_type = cpu_to_le16(conn->pkt_type);
267
268         hci_send_cmd(hdev, HCI_OP_ADD_SCO, sizeof(cp), &cp);
269 }
270
271 bool hci_setup_sync(struct hci_conn *conn, __u16 handle)
272 {
273         struct hci_dev *hdev = conn->hdev;
274         struct hci_cp_setup_sync_conn cp;
275         const struct sco_param *param;
276
277         BT_DBG("hcon %p", conn);
278
279         conn->state = BT_CONNECT;
280         conn->out = true;
281
282         conn->attempt++;
283
284         cp.handle   = cpu_to_le16(handle);
285
286         cp.tx_bandwidth   = cpu_to_le32(0x00001f40);
287         cp.rx_bandwidth   = cpu_to_le32(0x00001f40);
288         cp.voice_setting  = cpu_to_le16(conn->setting);
289
290         switch (conn->setting & SCO_AIRMODE_MASK) {
291         case SCO_AIRMODE_TRANSP:
292                 if (conn->attempt > ARRAY_SIZE(esco_param_msbc))
293                         return false;
294                 param = &esco_param_msbc[conn->attempt - 1];
295                 break;
296         case SCO_AIRMODE_CVSD:
297                 if (lmp_esco_capable(conn->link)) {
298                         if (conn->attempt > ARRAY_SIZE(esco_param_cvsd))
299                                 return false;
300                         param = &esco_param_cvsd[conn->attempt - 1];
301                 } else {
302                         if (conn->attempt > ARRAY_SIZE(sco_param_cvsd))
303                                 return false;
304                         param = &sco_param_cvsd[conn->attempt - 1];
305                 }
306                 break;
307         default:
308                 return false;
309         }
310
311         cp.retrans_effort = param->retrans_effort;
312         cp.pkt_type = __cpu_to_le16(param->pkt_type);
313         cp.max_latency = __cpu_to_le16(param->max_latency);
314
315         if (hci_send_cmd(hdev, HCI_OP_SETUP_SYNC_CONN, sizeof(cp), &cp) < 0)
316                 return false;
317
318         return true;
319 }
320
321 u8 hci_le_conn_update(struct hci_conn *conn, u16 min, u16 max, u16 latency,
322                       u16 to_multiplier)
323 {
324         struct hci_dev *hdev = conn->hdev;
325         struct hci_conn_params *params;
326         struct hci_cp_le_conn_update cp;
327
328         hci_dev_lock(hdev);
329
330         params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
331         if (params) {
332                 params->conn_min_interval = min;
333                 params->conn_max_interval = max;
334                 params->conn_latency = latency;
335                 params->supervision_timeout = to_multiplier;
336         }
337
338         hci_dev_unlock(hdev);
339
340         memset(&cp, 0, sizeof(cp));
341         cp.handle               = cpu_to_le16(conn->handle);
342         cp.conn_interval_min    = cpu_to_le16(min);
343         cp.conn_interval_max    = cpu_to_le16(max);
344         cp.conn_latency         = cpu_to_le16(latency);
345         cp.supervision_timeout  = cpu_to_le16(to_multiplier);
346         cp.min_ce_len           = cpu_to_le16(0x0000);
347         cp.max_ce_len           = cpu_to_le16(0x0000);
348
349         hci_send_cmd(hdev, HCI_OP_LE_CONN_UPDATE, sizeof(cp), &cp);
350
351         if (params)
352                 return 0x01;
353
354         return 0x00;
355 }
356
357 void hci_le_start_enc(struct hci_conn *conn, __le16 ediv, __le64 rand,
358                       __u8 ltk[16], __u8 key_size)
359 {
360         struct hci_dev *hdev = conn->hdev;
361         struct hci_cp_le_start_enc cp;
362
363         BT_DBG("hcon %p", conn);
364
365         memset(&cp, 0, sizeof(cp));
366
367         cp.handle = cpu_to_le16(conn->handle);
368         cp.rand = rand;
369         cp.ediv = ediv;
370         memcpy(cp.ltk, ltk, key_size);
371
372         hci_send_cmd(hdev, HCI_OP_LE_START_ENC, sizeof(cp), &cp);
373 }
374
375 /* Device _must_ be locked */
376 void hci_sco_setup(struct hci_conn *conn, __u8 status)
377 {
378         struct hci_conn *sco = conn->link;
379
380         if (!sco)
381                 return;
382
383         BT_DBG("hcon %p", conn);
384
385         if (!status) {
386                 if (lmp_esco_capable(conn->hdev))
387                         hci_setup_sync(sco, conn->handle);
388                 else
389                         hci_add_sco(sco, conn->handle);
390         } else {
391                 hci_connect_cfm(sco, status);
392                 hci_conn_del(sco);
393         }
394 }
395
396 static void hci_conn_timeout(struct work_struct *work)
397 {
398         struct hci_conn *conn = container_of(work, struct hci_conn,
399                                              disc_work.work);
400         int refcnt = atomic_read(&conn->refcnt);
401
402         BT_DBG("hcon %p state %s", conn, state_to_string(conn->state));
403
404         WARN_ON(refcnt < 0);
405
406         /* FIXME: It was observed that in pairing failed scenario, refcnt
407          * drops below 0. Probably this is because l2cap_conn_del calls
408          * l2cap_chan_del for each channel, and inside l2cap_chan_del conn is
409          * dropped. After that loop hci_chan_del is called which also drops
410          * conn. For now make sure that ACL is alive if refcnt is higher then 0,
411          * otherwise drop it.
412          */
413         if (refcnt > 0)
414                 return;
415
416         /* LE connections in scanning state need special handling */
417         if (conn->state == BT_CONNECT && conn->type == LE_LINK &&
418             test_bit(HCI_CONN_SCANNING, &conn->flags)) {
419                 hci_connect_le_scan_remove(conn);
420                 return;
421         }
422
423         hci_abort_conn(conn, hci_proto_disconn_ind(conn));
424 }
425
426 /* Enter sniff mode */
427 static void hci_conn_idle(struct work_struct *work)
428 {
429         struct hci_conn *conn = container_of(work, struct hci_conn,
430                                              idle_work.work);
431         struct hci_dev *hdev = conn->hdev;
432
433         BT_DBG("hcon %p mode %d", conn, conn->mode);
434
435         if (!lmp_sniff_capable(hdev) || !lmp_sniff_capable(conn))
436                 return;
437
438         if (conn->mode != HCI_CM_ACTIVE || !(conn->link_policy & HCI_LP_SNIFF))
439                 return;
440
441         if (lmp_sniffsubr_capable(hdev) && lmp_sniffsubr_capable(conn)) {
442                 struct hci_cp_sniff_subrate cp;
443                 cp.handle             = cpu_to_le16(conn->handle);
444                 cp.max_latency        = cpu_to_le16(0);
445                 cp.min_remote_timeout = cpu_to_le16(0);
446                 cp.min_local_timeout  = cpu_to_le16(0);
447                 hci_send_cmd(hdev, HCI_OP_SNIFF_SUBRATE, sizeof(cp), &cp);
448         }
449
450         if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
451                 struct hci_cp_sniff_mode cp;
452                 cp.handle       = cpu_to_le16(conn->handle);
453                 cp.max_interval = cpu_to_le16(hdev->sniff_max_interval);
454                 cp.min_interval = cpu_to_le16(hdev->sniff_min_interval);
455                 cp.attempt      = cpu_to_le16(4);
456                 cp.timeout      = cpu_to_le16(1);
457                 hci_send_cmd(hdev, HCI_OP_SNIFF_MODE, sizeof(cp), &cp);
458         }
459 }
460
461 static void hci_conn_auto_accept(struct work_struct *work)
462 {
463         struct hci_conn *conn = container_of(work, struct hci_conn,
464                                              auto_accept_work.work);
465
466         hci_send_cmd(conn->hdev, HCI_OP_USER_CONFIRM_REPLY, sizeof(conn->dst),
467                      &conn->dst);
468 }
469
470 static void le_conn_timeout(struct work_struct *work)
471 {
472         struct hci_conn *conn = container_of(work, struct hci_conn,
473                                              le_conn_timeout.work);
474         struct hci_dev *hdev = conn->hdev;
475
476         BT_DBG("");
477
478         /* We could end up here due to having done directed advertising,
479          * so clean up the state if necessary. This should however only
480          * happen with broken hardware or if low duty cycle was used
481          * (which doesn't have a timeout of its own).
482          */
483         if (conn->role == HCI_ROLE_SLAVE) {
484                 u8 enable = 0x00;
485                 hci_send_cmd(hdev, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
486                              &enable);
487                 hci_le_conn_failed(conn, HCI_ERROR_ADVERTISING_TIMEOUT);
488                 return;
489         }
490
491         hci_abort_conn(conn, HCI_ERROR_REMOTE_USER_TERM);
492 }
493
494 struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst,
495                               u8 role)
496 {
497         struct hci_conn *conn;
498
499         BT_DBG("%s dst %pMR", hdev->name, dst);
500
501         conn = kzalloc(sizeof(*conn), GFP_KERNEL);
502         if (!conn)
503                 return NULL;
504
505         bacpy(&conn->dst, dst);
506         bacpy(&conn->src, &hdev->bdaddr);
507         conn->hdev  = hdev;
508         conn->type  = type;
509         conn->role  = role;
510         conn->mode  = HCI_CM_ACTIVE;
511         conn->state = BT_OPEN;
512         conn->auth_type = HCI_AT_GENERAL_BONDING;
513         conn->io_capability = hdev->io_capability;
514         conn->remote_auth = 0xff;
515         conn->key_type = 0xff;
516         conn->rssi = HCI_RSSI_INVALID;
517         conn->tx_power = HCI_TX_POWER_INVALID;
518         conn->max_tx_power = HCI_TX_POWER_INVALID;
519
520         set_bit(HCI_CONN_POWER_SAVE, &conn->flags);
521         conn->disc_timeout = HCI_DISCONN_TIMEOUT;
522
523         if (conn->role == HCI_ROLE_MASTER)
524                 conn->out = true;
525
526         switch (type) {
527         case ACL_LINK:
528                 conn->pkt_type = hdev->pkt_type & ACL_PTYPE_MASK;
529                 break;
530         case LE_LINK:
531                 /* conn->src should reflect the local identity address */
532                 hci_copy_identity_address(hdev, &conn->src, &conn->src_type);
533                 break;
534         case SCO_LINK:
535                 if (lmp_esco_capable(hdev))
536                         conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
537                                         (hdev->esco_type & EDR_ESCO_MASK);
538                 else
539                         conn->pkt_type = hdev->pkt_type & SCO_PTYPE_MASK;
540                 break;
541         case ESCO_LINK:
542                 conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
543                 break;
544         }
545
546         skb_queue_head_init(&conn->data_q);
547
548         INIT_LIST_HEAD(&conn->chan_list);
549
550         INIT_DELAYED_WORK(&conn->disc_work, hci_conn_timeout);
551         INIT_DELAYED_WORK(&conn->auto_accept_work, hci_conn_auto_accept);
552         INIT_DELAYED_WORK(&conn->idle_work, hci_conn_idle);
553         INIT_DELAYED_WORK(&conn->le_conn_timeout, le_conn_timeout);
554         INIT_WORK(&conn->le_scan_cleanup, le_scan_cleanup);
555
556         atomic_set(&conn->refcnt, 0);
557
558         hci_dev_hold(hdev);
559
560         hci_conn_hash_add(hdev, conn);
561         if (hdev->notify)
562                 hdev->notify(hdev, HCI_NOTIFY_CONN_ADD);
563
564         hci_conn_init_sysfs(conn);
565
566         return conn;
567 }
568
569 int hci_conn_del(struct hci_conn *conn)
570 {
571         struct hci_dev *hdev = conn->hdev;
572
573         BT_DBG("%s hcon %p handle %d", hdev->name, conn, conn->handle);
574
575         cancel_delayed_work_sync(&conn->disc_work);
576         cancel_delayed_work_sync(&conn->auto_accept_work);
577         cancel_delayed_work_sync(&conn->idle_work);
578
579         if (conn->type == ACL_LINK) {
580                 struct hci_conn *sco = conn->link;
581                 if (sco)
582                         sco->link = NULL;
583
584                 /* Unacked frames */
585                 hdev->acl_cnt += conn->sent;
586         } else if (conn->type == LE_LINK) {
587                 cancel_delayed_work(&conn->le_conn_timeout);
588
589                 if (hdev->le_pkts)
590                         hdev->le_cnt += conn->sent;
591                 else
592                         hdev->acl_cnt += conn->sent;
593         } else {
594                 struct hci_conn *acl = conn->link;
595                 if (acl) {
596                         acl->link = NULL;
597                         hci_conn_drop(acl);
598                 }
599         }
600
601         if (conn->amp_mgr)
602                 amp_mgr_put(conn->amp_mgr);
603
604         skb_queue_purge(&conn->data_q);
605
606         /* Remove the connection from the list and cleanup its remaining
607          * state. This is a separate function since for some cases like
608          * BT_CONNECT_SCAN we *only* want the cleanup part without the
609          * rest of hci_conn_del.
610          */
611         hci_conn_cleanup(conn);
612
613         return 0;
614 }
615
616 struct hci_dev *hci_get_route(bdaddr_t *dst, bdaddr_t *src, uint8_t src_type)
617 {
618         int use_src = bacmp(src, BDADDR_ANY);
619         struct hci_dev *hdev = NULL, *d;
620
621         BT_DBG("%pMR -> %pMR", src, dst);
622
623         read_lock(&hci_dev_list_lock);
624
625         list_for_each_entry(d, &hci_dev_list, list) {
626                 if (!test_bit(HCI_UP, &d->flags) ||
627                     hci_dev_test_flag(d, HCI_USER_CHANNEL) ||
628                     d->dev_type != HCI_PRIMARY)
629                         continue;
630
631                 /* Simple routing:
632                  *   No source address - find interface with bdaddr != dst
633                  *   Source address    - find interface with bdaddr == src
634                  */
635
636                 if (use_src) {
637                         bdaddr_t id_addr;
638                         u8 id_addr_type;
639
640                         if (src_type == BDADDR_BREDR) {
641                                 if (!lmp_bredr_capable(d))
642                                         continue;
643                                 bacpy(&id_addr, &d->bdaddr);
644                                 id_addr_type = BDADDR_BREDR;
645                         } else {
646                                 if (!lmp_le_capable(d))
647                                         continue;
648
649                                 hci_copy_identity_address(d, &id_addr,
650                                                           &id_addr_type);
651
652                                 /* Convert from HCI to three-value type */
653                                 if (id_addr_type == ADDR_LE_DEV_PUBLIC)
654                                         id_addr_type = BDADDR_LE_PUBLIC;
655                                 else
656                                         id_addr_type = BDADDR_LE_RANDOM;
657                         }
658
659                         if (!bacmp(&id_addr, src) && id_addr_type == src_type) {
660                                 hdev = d; break;
661                         }
662                 } else {
663                         if (bacmp(&d->bdaddr, dst)) {
664                                 hdev = d; break;
665                         }
666                 }
667         }
668
669         if (hdev)
670                 hdev = hci_dev_hold(hdev);
671
672         read_unlock(&hci_dev_list_lock);
673         return hdev;
674 }
675 EXPORT_SYMBOL(hci_get_route);
676
677 /* This function requires the caller holds hdev->lock */
678 void hci_le_conn_failed(struct hci_conn *conn, u8 status)
679 {
680         struct hci_dev *hdev = conn->hdev;
681         struct hci_conn_params *params;
682
683         params = hci_pend_le_action_lookup(&hdev->pend_le_conns, &conn->dst,
684                                            conn->dst_type);
685         if (params && params->conn) {
686                 hci_conn_drop(params->conn);
687                 hci_conn_put(params->conn);
688                 params->conn = NULL;
689         }
690
691         conn->state = BT_CLOSED;
692
693         /* If the status indicates successful cancellation of
694          * the attempt (i.e. Unkown Connection Id) there's no point of
695          * notifying failure since we'll go back to keep trying to
696          * connect. The only exception is explicit connect requests
697          * where a timeout + cancel does indicate an actual failure.
698          */
699         if (status != HCI_ERROR_UNKNOWN_CONN_ID ||
700             (params && params->explicit_connect))
701                 mgmt_connect_failed(hdev, &conn->dst, conn->type,
702                                     conn->dst_type, status);
703
704         hci_connect_cfm(conn, status);
705
706         hci_conn_del(conn);
707
708         /* Since we may have temporarily stopped the background scanning in
709          * favor of connection establishment, we should restart it.
710          */
711         hci_update_background_scan(hdev);
712
713         /* Re-enable advertising in case this was a failed connection
714          * attempt as a peripheral.
715          */
716         hci_req_reenable_advertising(hdev);
717 }
718
719 static void create_le_conn_complete(struct hci_dev *hdev, u8 status, u16 opcode)
720 {
721         struct hci_conn *conn;
722
723         hci_dev_lock(hdev);
724
725         conn = hci_lookup_le_connect(hdev);
726
727         if (!status) {
728                 hci_connect_le_scan_cleanup(conn);
729                 goto done;
730         }
731
732         bt_dev_err(hdev, "request failed to create LE connection: "
733                    "status 0x%2.2x", status);
734
735         if (!conn)
736                 goto done;
737
738         hci_le_conn_failed(conn, status);
739
740 done:
741         hci_dev_unlock(hdev);
742 }
743
744 static bool conn_use_rpa(struct hci_conn *conn)
745 {
746         struct hci_dev *hdev = conn->hdev;
747
748         return hci_dev_test_flag(hdev, HCI_PRIVACY);
749 }
750
751 static void set_ext_conn_params(struct hci_conn *conn,
752                                 struct hci_cp_le_ext_conn_param *p)
753 {
754         struct hci_dev *hdev = conn->hdev;
755
756         memset(p, 0, sizeof(*p));
757
758         /* Set window to be the same value as the interval to
759          * enable continuous scanning.
760          */
761         p->scan_interval = cpu_to_le16(hdev->le_scan_interval);
762         p->scan_window = p->scan_interval;
763         p->conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
764         p->conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
765         p->conn_latency = cpu_to_le16(conn->le_conn_latency);
766         p->supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
767         p->min_ce_len = cpu_to_le16(0x0000);
768         p->max_ce_len = cpu_to_le16(0x0000);
769 }
770
771 static void hci_req_add_le_create_conn(struct hci_request *req,
772                                        struct hci_conn *conn,
773                                        bdaddr_t *direct_rpa)
774 {
775         struct hci_dev *hdev = conn->hdev;
776         u8 own_addr_type;
777
778         /* If direct address was provided we use it instead of current
779          * address.
780          */
781         if (direct_rpa) {
782                 if (bacmp(&req->hdev->random_addr, direct_rpa))
783                         hci_req_add(req, HCI_OP_LE_SET_RANDOM_ADDR, 6,
784                                                                 direct_rpa);
785
786                 /* direct address is always RPA */
787                 own_addr_type = ADDR_LE_DEV_RANDOM;
788         } else {
789                 /* Update random address, but set require_privacy to false so
790                  * that we never connect with an non-resolvable address.
791                  */
792                 if (hci_update_random_address(req, false, conn_use_rpa(conn),
793                                               &own_addr_type))
794                         return;
795         }
796
797         if (use_ext_conn(hdev)) {
798                 struct hci_cp_le_ext_create_conn *cp;
799                 struct hci_cp_le_ext_conn_param *p;
800                 u8 data[sizeof(*cp) + sizeof(*p) * 3];
801                 u32 plen;
802
803                 cp = (void *) data;
804                 p = (void *) cp->data;
805
806                 memset(cp, 0, sizeof(*cp));
807
808                 bacpy(&cp->peer_addr, &conn->dst);
809                 cp->peer_addr_type = conn->dst_type;
810                 cp->own_addr_type = own_addr_type;
811
812                 plen = sizeof(*cp);
813
814                 if (scan_1m(hdev)) {
815                         cp->phys |= LE_SCAN_PHY_1M;
816                         set_ext_conn_params(conn, p);
817
818                         p++;
819                         plen += sizeof(*p);
820                 }
821
822                 if (scan_2m(hdev)) {
823                         cp->phys |= LE_SCAN_PHY_2M;
824                         set_ext_conn_params(conn, p);
825
826                         p++;
827                         plen += sizeof(*p);
828                 }
829
830                 if (scan_coded(hdev)) {
831                         cp->phys |= LE_SCAN_PHY_CODED;
832                         set_ext_conn_params(conn, p);
833
834                         plen += sizeof(*p);
835                 }
836
837                 hci_req_add(req, HCI_OP_LE_EXT_CREATE_CONN, plen, data);
838
839         } else {
840                 struct hci_cp_le_create_conn cp;
841
842                 memset(&cp, 0, sizeof(cp));
843
844                 /* Set window to be the same value as the interval to enable
845                  * continuous scanning.
846                  */
847                 cp.scan_interval = cpu_to_le16(hdev->le_scan_interval);
848                 cp.scan_window = cp.scan_interval;
849
850                 bacpy(&cp.peer_addr, &conn->dst);
851                 cp.peer_addr_type = conn->dst_type;
852                 cp.own_address_type = own_addr_type;
853                 cp.conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
854                 cp.conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
855                 cp.conn_latency = cpu_to_le16(conn->le_conn_latency);
856                 cp.supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
857                 cp.min_ce_len = cpu_to_le16(0x0000);
858                 cp.max_ce_len = cpu_to_le16(0x0000);
859
860                 hci_req_add(req, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp);
861         }
862
863         conn->state = BT_CONNECT;
864         clear_bit(HCI_CONN_SCANNING, &conn->flags);
865 }
866
867 static void hci_req_directed_advertising(struct hci_request *req,
868                                          struct hci_conn *conn)
869 {
870         struct hci_dev *hdev = req->hdev;
871         u8 own_addr_type;
872         u8 enable;
873
874         if (ext_adv_capable(hdev)) {
875                 struct hci_cp_le_set_ext_adv_params cp;
876                 bdaddr_t random_addr;
877
878                 /* Set require_privacy to false so that the remote device has a
879                  * chance of identifying us.
880                  */
881                 if (hci_get_random_address(hdev, false, conn_use_rpa(conn), NULL,
882                                            &own_addr_type, &random_addr) < 0)
883                         return;
884
885                 memset(&cp, 0, sizeof(cp));
886
887                 cp.evt_properties = cpu_to_le16(LE_LEGACY_ADV_DIRECT_IND);
888                 cp.own_addr_type = own_addr_type;
889                 cp.channel_map = hdev->le_adv_channel_map;
890                 cp.tx_power = HCI_TX_POWER_INVALID;
891                 cp.primary_phy = HCI_ADV_PHY_1M;
892                 cp.secondary_phy = HCI_ADV_PHY_1M;
893                 cp.handle = 0; /* Use instance 0 for directed adv */
894                 cp.own_addr_type = own_addr_type;
895                 cp.peer_addr_type = conn->dst_type;
896                 bacpy(&cp.peer_addr, &conn->dst);
897
898                 hci_req_add(req, HCI_OP_LE_SET_EXT_ADV_PARAMS, sizeof(cp), &cp);
899
900                 if (own_addr_type == ADDR_LE_DEV_RANDOM &&
901                     bacmp(&random_addr, BDADDR_ANY) &&
902                     bacmp(&random_addr, &hdev->random_addr)) {
903                         struct hci_cp_le_set_adv_set_rand_addr cp;
904
905                         memset(&cp, 0, sizeof(cp));
906
907                         cp.handle = 0;
908                         bacpy(&cp.bdaddr, &random_addr);
909
910                         hci_req_add(req,
911                                     HCI_OP_LE_SET_ADV_SET_RAND_ADDR,
912                                     sizeof(cp), &cp);
913                 }
914
915                 __hci_req_enable_ext_advertising(req);
916         } else {
917                 struct hci_cp_le_set_adv_param cp;
918
919                 /* Clear the HCI_LE_ADV bit temporarily so that the
920                  * hci_update_random_address knows that it's safe to go ahead
921                  * and write a new random address. The flag will be set back on
922                  * as soon as the SET_ADV_ENABLE HCI command completes.
923                  */
924                 hci_dev_clear_flag(hdev, HCI_LE_ADV);
925
926                 /* Set require_privacy to false so that the remote device has a
927                  * chance of identifying us.
928                  */
929                 if (hci_update_random_address(req, false, conn_use_rpa(conn),
930                                               &own_addr_type) < 0)
931                         return;
932
933                 memset(&cp, 0, sizeof(cp));
934
935                 /* Some controllers might reject command if intervals are not
936                  * within range for undirected advertising.
937                  * BCM20702A0 is known to be affected by this.
938                  */
939                 cp.min_interval = cpu_to_le16(0x0020);
940                 cp.max_interval = cpu_to_le16(0x0020);
941
942                 cp.type = LE_ADV_DIRECT_IND;
943                 cp.own_address_type = own_addr_type;
944                 cp.direct_addr_type = conn->dst_type;
945                 bacpy(&cp.direct_addr, &conn->dst);
946                 cp.channel_map = hdev->le_adv_channel_map;
947
948                 hci_req_add(req, HCI_OP_LE_SET_ADV_PARAM, sizeof(cp), &cp);
949
950                 enable = 0x01;
951                 hci_req_add(req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
952                             &enable);
953         }
954
955         conn->state = BT_CONNECT;
956 }
957
958 struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
959                                 u8 dst_type, u8 sec_level, u16 conn_timeout,
960                                 u8 role, bdaddr_t *direct_rpa)
961 {
962         struct hci_conn_params *params;
963         struct hci_conn *conn;
964         struct smp_irk *irk;
965         struct hci_request req;
966         int err;
967
968         /* Let's make sure that le is enabled.*/
969         if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
970                 if (lmp_le_capable(hdev))
971                         return ERR_PTR(-ECONNREFUSED);
972
973                 return ERR_PTR(-EOPNOTSUPP);
974         }
975
976         /* Since the controller supports only one LE connection attempt at a
977          * time, we return -EBUSY if there is any connection attempt running.
978          */
979         if (hci_lookup_le_connect(hdev))
980                 return ERR_PTR(-EBUSY);
981
982         /* If there's already a connection object but it's not in
983          * scanning state it means it must already be established, in
984          * which case we can't do anything else except report a failure
985          * to connect.
986          */
987         conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
988         if (conn && !test_bit(HCI_CONN_SCANNING, &conn->flags)) {
989                 return ERR_PTR(-EBUSY);
990         }
991
992         /* When given an identity address with existing identity
993          * resolving key, the connection needs to be established
994          * to a resolvable random address.
995          *
996          * Storing the resolvable random address is required here
997          * to handle connection failures. The address will later
998          * be resolved back into the original identity address
999          * from the connect request.
1000          */
1001         irk = hci_find_irk_by_addr(hdev, dst, dst_type);
1002         if (irk && bacmp(&irk->rpa, BDADDR_ANY)) {
1003                 dst = &irk->rpa;
1004                 dst_type = ADDR_LE_DEV_RANDOM;
1005         }
1006
1007         if (conn) {
1008                 bacpy(&conn->dst, dst);
1009         } else {
1010                 conn = hci_conn_add(hdev, LE_LINK, dst, role);
1011                 if (!conn)
1012                         return ERR_PTR(-ENOMEM);
1013                 hci_conn_hold(conn);
1014                 conn->pending_sec_level = sec_level;
1015         }
1016
1017         conn->dst_type = dst_type;
1018         conn->sec_level = BT_SECURITY_LOW;
1019         conn->conn_timeout = conn_timeout;
1020
1021         hci_req_init(&req, hdev);
1022
1023         /* Disable advertising if we're active. For master role
1024          * connections most controllers will refuse to connect if
1025          * advertising is enabled, and for slave role connections we
1026          * anyway have to disable it in order to start directed
1027          * advertising.
1028          */
1029         if (hci_dev_test_flag(hdev, HCI_LE_ADV)) {
1030                 u8 enable = 0x00;
1031                 hci_req_add(&req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
1032                             &enable);
1033         }
1034
1035         /* If requested to connect as slave use directed advertising */
1036         if (conn->role == HCI_ROLE_SLAVE) {
1037                 /* If we're active scanning most controllers are unable
1038                  * to initiate advertising. Simply reject the attempt.
1039                  */
1040                 if (hci_dev_test_flag(hdev, HCI_LE_SCAN) &&
1041                     hdev->le_scan_type == LE_SCAN_ACTIVE) {
1042                         hci_req_purge(&req);
1043                         hci_conn_del(conn);
1044                         return ERR_PTR(-EBUSY);
1045                 }
1046
1047                 hci_req_directed_advertising(&req, conn);
1048                 goto create_conn;
1049         }
1050
1051         params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
1052         if (params) {
1053                 conn->le_conn_min_interval = params->conn_min_interval;
1054                 conn->le_conn_max_interval = params->conn_max_interval;
1055                 conn->le_conn_latency = params->conn_latency;
1056                 conn->le_supv_timeout = params->supervision_timeout;
1057         } else {
1058                 conn->le_conn_min_interval = hdev->le_conn_min_interval;
1059                 conn->le_conn_max_interval = hdev->le_conn_max_interval;
1060                 conn->le_conn_latency = hdev->le_conn_latency;
1061                 conn->le_supv_timeout = hdev->le_supv_timeout;
1062         }
1063
1064         /* If controller is scanning, we stop it since some controllers are
1065          * not able to scan and connect at the same time. Also set the
1066          * HCI_LE_SCAN_INTERRUPTED flag so that the command complete
1067          * handler for scan disabling knows to set the correct discovery
1068          * state.
1069          */
1070         if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) {
1071                 hci_req_add_le_scan_disable(&req);
1072                 hci_dev_set_flag(hdev, HCI_LE_SCAN_INTERRUPTED);
1073         }
1074
1075         hci_req_add_le_create_conn(&req, conn, direct_rpa);
1076
1077 create_conn:
1078         err = hci_req_run(&req, create_le_conn_complete);
1079         if (err) {
1080                 hci_conn_del(conn);
1081                 return ERR_PTR(err);
1082         }
1083
1084         return conn;
1085 }
1086
1087 static bool is_connected(struct hci_dev *hdev, bdaddr_t *addr, u8 type)
1088 {
1089         struct hci_conn *conn;
1090
1091         conn = hci_conn_hash_lookup_le(hdev, addr, type);
1092         if (!conn)
1093                 return false;
1094
1095         if (conn->state != BT_CONNECTED)
1096                 return false;
1097
1098         return true;
1099 }
1100
1101 /* This function requires the caller holds hdev->lock */
1102 static int hci_explicit_conn_params_set(struct hci_dev *hdev,
1103                                         bdaddr_t *addr, u8 addr_type)
1104 {
1105         struct hci_conn_params *params;
1106
1107         if (is_connected(hdev, addr, addr_type))
1108                 return -EISCONN;
1109
1110         params = hci_conn_params_lookup(hdev, addr, addr_type);
1111         if (!params) {
1112                 params = hci_conn_params_add(hdev, addr, addr_type);
1113                 if (!params)
1114                         return -ENOMEM;
1115
1116                 /* If we created new params, mark them to be deleted in
1117                  * hci_connect_le_scan_cleanup. It's different case than
1118                  * existing disabled params, those will stay after cleanup.
1119                  */
1120                 params->auto_connect = HCI_AUTO_CONN_EXPLICIT;
1121         }
1122
1123         /* We're trying to connect, so make sure params are at pend_le_conns */
1124         if (params->auto_connect == HCI_AUTO_CONN_DISABLED ||
1125             params->auto_connect == HCI_AUTO_CONN_REPORT ||
1126             params->auto_connect == HCI_AUTO_CONN_EXPLICIT) {
1127                 list_del_init(&params->action);
1128                 list_add(&params->action, &hdev->pend_le_conns);
1129         }
1130
1131         params->explicit_connect = true;
1132
1133         BT_DBG("addr %pMR (type %u) auto_connect %u", addr, addr_type,
1134                params->auto_connect);
1135
1136         return 0;
1137 }
1138
1139 /* This function requires the caller holds hdev->lock */
1140 struct hci_conn *hci_connect_le_scan(struct hci_dev *hdev, bdaddr_t *dst,
1141                                      u8 dst_type, u8 sec_level,
1142                                      u16 conn_timeout)
1143 {
1144         struct hci_conn *conn;
1145
1146         /* Let's make sure that le is enabled.*/
1147         if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
1148                 if (lmp_le_capable(hdev))
1149                         return ERR_PTR(-ECONNREFUSED);
1150
1151                 return ERR_PTR(-EOPNOTSUPP);
1152         }
1153
1154         /* Some devices send ATT messages as soon as the physical link is
1155          * established. To be able to handle these ATT messages, the user-
1156          * space first establishes the connection and then starts the pairing
1157          * process.
1158          *
1159          * So if a hci_conn object already exists for the following connection
1160          * attempt, we simply update pending_sec_level and auth_type fields
1161          * and return the object found.
1162          */
1163         conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
1164         if (conn) {
1165                 if (conn->pending_sec_level < sec_level)
1166                         conn->pending_sec_level = sec_level;
1167                 goto done;
1168         }
1169
1170         BT_DBG("requesting refresh of dst_addr");
1171
1172         conn = hci_conn_add(hdev, LE_LINK, dst, HCI_ROLE_MASTER);
1173         if (!conn)
1174                 return ERR_PTR(-ENOMEM);
1175
1176         if (hci_explicit_conn_params_set(hdev, dst, dst_type) < 0)
1177                 return ERR_PTR(-EBUSY);
1178
1179         conn->state = BT_CONNECT;
1180         set_bit(HCI_CONN_SCANNING, &conn->flags);
1181         conn->dst_type = dst_type;
1182         conn->sec_level = BT_SECURITY_LOW;
1183         conn->pending_sec_level = sec_level;
1184         conn->conn_timeout = conn_timeout;
1185
1186         hci_update_background_scan(hdev);
1187
1188 done:
1189         hci_conn_hold(conn);
1190         return conn;
1191 }
1192
1193 struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
1194                                  u8 sec_level, u8 auth_type)
1195 {
1196         struct hci_conn *acl;
1197
1198         if (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED)) {
1199                 if (lmp_bredr_capable(hdev))
1200                         return ERR_PTR(-ECONNREFUSED);
1201
1202                 return ERR_PTR(-EOPNOTSUPP);
1203         }
1204
1205         acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
1206         if (!acl) {
1207                 acl = hci_conn_add(hdev, ACL_LINK, dst, HCI_ROLE_MASTER);
1208                 if (!acl)
1209                         return ERR_PTR(-ENOMEM);
1210         }
1211
1212         hci_conn_hold(acl);
1213
1214         if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
1215                 acl->sec_level = BT_SECURITY_LOW;
1216                 acl->pending_sec_level = sec_level;
1217                 acl->auth_type = auth_type;
1218                 hci_acl_create_connection(acl);
1219         }
1220
1221         return acl;
1222 }
1223
1224 struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type, bdaddr_t *dst,
1225                                  __u16 setting)
1226 {
1227         struct hci_conn *acl;
1228         struct hci_conn *sco;
1229
1230         acl = hci_connect_acl(hdev, dst, BT_SECURITY_LOW, HCI_AT_NO_BONDING);
1231         if (IS_ERR(acl))
1232                 return acl;
1233
1234         sco = hci_conn_hash_lookup_ba(hdev, type, dst);
1235         if (!sco) {
1236                 sco = hci_conn_add(hdev, type, dst, HCI_ROLE_MASTER);
1237                 if (!sco) {
1238                         hci_conn_drop(acl);
1239                         return ERR_PTR(-ENOMEM);
1240                 }
1241         }
1242
1243         acl->link = sco;
1244         sco->link = acl;
1245
1246         hci_conn_hold(sco);
1247
1248         sco->setting = setting;
1249
1250         if (acl->state == BT_CONNECTED &&
1251             (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
1252                 set_bit(HCI_CONN_POWER_SAVE, &acl->flags);
1253                 hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);
1254
1255                 if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->flags)) {
1256                         /* defer SCO setup until mode change completed */
1257                         set_bit(HCI_CONN_SCO_SETUP_PEND, &acl->flags);
1258                         return sco;
1259                 }
1260
1261                 hci_sco_setup(acl, 0x00);
1262         }
1263
1264         return sco;
1265 }
1266
1267 /* Check link security requirement */
1268 int hci_conn_check_link_mode(struct hci_conn *conn)
1269 {
1270         BT_DBG("hcon %p", conn);
1271
1272         /* In Secure Connections Only mode, it is required that Secure
1273          * Connections is used and the link is encrypted with AES-CCM
1274          * using a P-256 authenticated combination key.
1275          */
1276         if (hci_dev_test_flag(conn->hdev, HCI_SC_ONLY)) {
1277                 if (!hci_conn_sc_enabled(conn) ||
1278                     !test_bit(HCI_CONN_AES_CCM, &conn->flags) ||
1279                     conn->key_type != HCI_LK_AUTH_COMBINATION_P256)
1280                         return 0;
1281         }
1282
1283         /* If Secure Simple Pairing is not enabled, then legacy connection
1284          * setup is used and no encryption or key sizes can be enforced.
1285          */
1286         if (!hci_conn_ssp_enabled(conn))
1287                 return 1;
1288
1289         if (!test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1290                 return 0;
1291
1292         return 1;
1293 }
1294
1295 /* Authenticate remote device */
1296 static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
1297 {
1298         BT_DBG("hcon %p", conn);
1299
1300         if (conn->pending_sec_level > sec_level)
1301                 sec_level = conn->pending_sec_level;
1302
1303         if (sec_level > conn->sec_level)
1304                 conn->pending_sec_level = sec_level;
1305         else if (test_bit(HCI_CONN_AUTH, &conn->flags))
1306                 return 1;
1307
1308         /* Make sure we preserve an existing MITM requirement*/
1309         auth_type |= (conn->auth_type & 0x01);
1310
1311         conn->auth_type = auth_type;
1312
1313         if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
1314                 struct hci_cp_auth_requested cp;
1315
1316                 cp.handle = cpu_to_le16(conn->handle);
1317                 hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
1318                              sizeof(cp), &cp);
1319
1320                 /* If we're already encrypted set the REAUTH_PEND flag,
1321                  * otherwise set the ENCRYPT_PEND.
1322                  */
1323                 if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1324                         set_bit(HCI_CONN_REAUTH_PEND, &conn->flags);
1325                 else
1326                         set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags);
1327         }
1328
1329         return 0;
1330 }
1331
1332 /* Encrypt the the link */
1333 static void hci_conn_encrypt(struct hci_conn *conn)
1334 {
1335         BT_DBG("hcon %p", conn);
1336
1337         if (!test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) {
1338                 struct hci_cp_set_conn_encrypt cp;
1339                 cp.handle  = cpu_to_le16(conn->handle);
1340                 cp.encrypt = 0x01;
1341                 hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp),
1342                              &cp);
1343         }
1344 }
1345
1346 /* Enable security */
1347 int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type,
1348                       bool initiator)
1349 {
1350         BT_DBG("hcon %p", conn);
1351
1352         if (conn->type == LE_LINK)
1353                 return smp_conn_security(conn, sec_level);
1354
1355         /* For sdp we don't need the link key. */
1356         if (sec_level == BT_SECURITY_SDP)
1357                 return 1;
1358
1359         /* For non 2.1 devices and low security level we don't need the link
1360            key. */
1361         if (sec_level == BT_SECURITY_LOW && !hci_conn_ssp_enabled(conn))
1362                 return 1;
1363
1364         /* For other security levels we need the link key. */
1365         if (!test_bit(HCI_CONN_AUTH, &conn->flags))
1366                 goto auth;
1367
1368         /* An authenticated FIPS approved combination key has sufficient
1369          * security for security level 4. */
1370         if (conn->key_type == HCI_LK_AUTH_COMBINATION_P256 &&
1371             sec_level == BT_SECURITY_FIPS)
1372                 goto encrypt;
1373
1374         /* An authenticated combination key has sufficient security for
1375            security level 3. */
1376         if ((conn->key_type == HCI_LK_AUTH_COMBINATION_P192 ||
1377              conn->key_type == HCI_LK_AUTH_COMBINATION_P256) &&
1378             sec_level == BT_SECURITY_HIGH)
1379                 goto encrypt;
1380
1381         /* An unauthenticated combination key has sufficient security for
1382            security level 1 and 2. */
1383         if ((conn->key_type == HCI_LK_UNAUTH_COMBINATION_P192 ||
1384              conn->key_type == HCI_LK_UNAUTH_COMBINATION_P256) &&
1385             (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW))
1386                 goto encrypt;
1387
1388         /* A combination key has always sufficient security for the security
1389            levels 1 or 2. High security level requires the combination key
1390            is generated using maximum PIN code length (16).
1391            For pre 2.1 units. */
1392         if (conn->key_type == HCI_LK_COMBINATION &&
1393             (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW ||
1394              conn->pin_length == 16))
1395                 goto encrypt;
1396
1397 auth:
1398         if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags))
1399                 return 0;
1400
1401         if (initiator)
1402                 set_bit(HCI_CONN_AUTH_INITIATOR, &conn->flags);
1403
1404         if (!hci_conn_auth(conn, sec_level, auth_type))
1405                 return 0;
1406
1407 encrypt:
1408         if (test_bit(HCI_CONN_ENCRYPT, &conn->flags)) {
1409                 /* Ensure that the encryption key size has been read,
1410                  * otherwise stall the upper layer responses.
1411                  */
1412                 if (!conn->enc_key_size)
1413                         return 0;
1414
1415                 /* Nothing else needed, all requirements are met */
1416                 return 1;
1417         }
1418
1419         hci_conn_encrypt(conn);
1420         return 0;
1421 }
1422 EXPORT_SYMBOL(hci_conn_security);
1423
1424 /* Check secure link requirement */
1425 int hci_conn_check_secure(struct hci_conn *conn, __u8 sec_level)
1426 {
1427         BT_DBG("hcon %p", conn);
1428
1429         /* Accept if non-secure or higher security level is required */
1430         if (sec_level != BT_SECURITY_HIGH && sec_level != BT_SECURITY_FIPS)
1431                 return 1;
1432
1433         /* Accept if secure or higher security level is already present */
1434         if (conn->sec_level == BT_SECURITY_HIGH ||
1435             conn->sec_level == BT_SECURITY_FIPS)
1436                 return 1;
1437
1438         /* Reject not secure link */
1439         return 0;
1440 }
1441 EXPORT_SYMBOL(hci_conn_check_secure);
1442
1443 /* Switch role */
1444 int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
1445 {
1446         BT_DBG("hcon %p", conn);
1447
1448         if (role == conn->role)
1449                 return 1;
1450
1451         if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->flags)) {
1452                 struct hci_cp_switch_role cp;
1453                 bacpy(&cp.bdaddr, &conn->dst);
1454                 cp.role = role;
1455                 hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
1456         }
1457
1458         return 0;
1459 }
1460 EXPORT_SYMBOL(hci_conn_switch_role);
1461
1462 /* Enter active mode */
1463 void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
1464 {
1465         struct hci_dev *hdev = conn->hdev;
1466
1467         BT_DBG("hcon %p mode %d", conn, conn->mode);
1468
1469         if (conn->mode != HCI_CM_SNIFF)
1470                 goto timer;
1471
1472         if (!test_bit(HCI_CONN_POWER_SAVE, &conn->flags) && !force_active)
1473                 goto timer;
1474
1475         if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
1476                 struct hci_cp_exit_sniff_mode cp;
1477                 cp.handle = cpu_to_le16(conn->handle);
1478                 hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
1479         }
1480
1481 timer:
1482         if (hdev->idle_timeout > 0)
1483                 queue_delayed_work(hdev->workqueue, &conn->idle_work,
1484                                    msecs_to_jiffies(hdev->idle_timeout));
1485 }
1486
1487 /* Drop all connection on the device */
1488 void hci_conn_hash_flush(struct hci_dev *hdev)
1489 {
1490         struct hci_conn_hash *h = &hdev->conn_hash;
1491         struct hci_conn *c, *n;
1492
1493         BT_DBG("hdev %s", hdev->name);
1494
1495         list_for_each_entry_safe(c, n, &h->list, list) {
1496                 c->state = BT_CLOSED;
1497
1498                 hci_disconn_cfm(c, HCI_ERROR_LOCAL_HOST_TERM);
1499                 hci_conn_del(c);
1500         }
1501 }
1502
1503 /* Check pending connect attempts */
1504 void hci_conn_check_pending(struct hci_dev *hdev)
1505 {
1506         struct hci_conn *conn;
1507
1508         BT_DBG("hdev %s", hdev->name);
1509
1510         hci_dev_lock(hdev);
1511
1512         conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
1513         if (conn)
1514                 hci_acl_create_connection(conn);
1515
1516         hci_dev_unlock(hdev);
1517 }
1518
1519 static u32 get_link_mode(struct hci_conn *conn)
1520 {
1521         u32 link_mode = 0;
1522
1523         if (conn->role == HCI_ROLE_MASTER)
1524                 link_mode |= HCI_LM_MASTER;
1525
1526         if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1527                 link_mode |= HCI_LM_ENCRYPT;
1528
1529         if (test_bit(HCI_CONN_AUTH, &conn->flags))
1530                 link_mode |= HCI_LM_AUTH;
1531
1532         if (test_bit(HCI_CONN_SECURE, &conn->flags))
1533                 link_mode |= HCI_LM_SECURE;
1534
1535         if (test_bit(HCI_CONN_FIPS, &conn->flags))
1536                 link_mode |= HCI_LM_FIPS;
1537
1538         return link_mode;
1539 }
1540
1541 int hci_get_conn_list(void __user *arg)
1542 {
1543         struct hci_conn *c;
1544         struct hci_conn_list_req req, *cl;
1545         struct hci_conn_info *ci;
1546         struct hci_dev *hdev;
1547         int n = 0, size, err;
1548
1549         if (copy_from_user(&req, arg, sizeof(req)))
1550                 return -EFAULT;
1551
1552         if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
1553                 return -EINVAL;
1554
1555         size = sizeof(req) + req.conn_num * sizeof(*ci);
1556
1557         cl = kmalloc(size, GFP_KERNEL);
1558         if (!cl)
1559                 return -ENOMEM;
1560
1561         hdev = hci_dev_get(req.dev_id);
1562         if (!hdev) {
1563                 kfree(cl);
1564                 return -ENODEV;
1565         }
1566
1567         ci = cl->conn_info;
1568
1569         hci_dev_lock(hdev);
1570         list_for_each_entry(c, &hdev->conn_hash.list, list) {
1571                 bacpy(&(ci + n)->bdaddr, &c->dst);
1572                 (ci + n)->handle = c->handle;
1573                 (ci + n)->type  = c->type;
1574                 (ci + n)->out   = c->out;
1575                 (ci + n)->state = c->state;
1576                 (ci + n)->link_mode = get_link_mode(c);
1577                 if (++n >= req.conn_num)
1578                         break;
1579         }
1580         hci_dev_unlock(hdev);
1581
1582         cl->dev_id = hdev->id;
1583         cl->conn_num = n;
1584         size = sizeof(req) + n * sizeof(*ci);
1585
1586         hci_dev_put(hdev);
1587
1588         err = copy_to_user(arg, cl, size);
1589         kfree(cl);
1590
1591         return err ? -EFAULT : 0;
1592 }
1593
1594 int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
1595 {
1596         struct hci_conn_info_req req;
1597         struct hci_conn_info ci;
1598         struct hci_conn *conn;
1599         char __user *ptr = arg + sizeof(req);
1600
1601         if (copy_from_user(&req, arg, sizeof(req)))
1602                 return -EFAULT;
1603
1604         hci_dev_lock(hdev);
1605         conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
1606         if (conn) {
1607                 bacpy(&ci.bdaddr, &conn->dst);
1608                 ci.handle = conn->handle;
1609                 ci.type  = conn->type;
1610                 ci.out   = conn->out;
1611                 ci.state = conn->state;
1612                 ci.link_mode = get_link_mode(conn);
1613         }
1614         hci_dev_unlock(hdev);
1615
1616         if (!conn)
1617                 return -ENOENT;
1618
1619         return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
1620 }
1621
1622 int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
1623 {
1624         struct hci_auth_info_req req;
1625         struct hci_conn *conn;
1626
1627         if (copy_from_user(&req, arg, sizeof(req)))
1628                 return -EFAULT;
1629
1630         hci_dev_lock(hdev);
1631         conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
1632         if (conn)
1633                 req.type = conn->auth_type;
1634         hci_dev_unlock(hdev);
1635
1636         if (!conn)
1637                 return -ENOENT;
1638
1639         return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
1640 }
1641
1642 struct hci_chan *hci_chan_create(struct hci_conn *conn)
1643 {
1644         struct hci_dev *hdev = conn->hdev;
1645         struct hci_chan *chan;
1646
1647         BT_DBG("%s hcon %p", hdev->name, conn);
1648
1649         if (test_bit(HCI_CONN_DROP, &conn->flags)) {
1650                 BT_DBG("Refusing to create new hci_chan");
1651                 return NULL;
1652         }
1653
1654         chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1655         if (!chan)
1656                 return NULL;
1657
1658         chan->conn = hci_conn_get(conn);
1659         skb_queue_head_init(&chan->data_q);
1660         chan->state = BT_CONNECTED;
1661
1662         list_add_rcu(&chan->list, &conn->chan_list);
1663
1664         return chan;
1665 }
1666
1667 void hci_chan_del(struct hci_chan *chan)
1668 {
1669         struct hci_conn *conn = chan->conn;
1670         struct hci_dev *hdev = conn->hdev;
1671
1672         BT_DBG("%s hcon %p chan %p", hdev->name, conn, chan);
1673
1674         list_del_rcu(&chan->list);
1675
1676         synchronize_rcu();
1677
1678         /* Prevent new hci_chan's to be created for this hci_conn */
1679         set_bit(HCI_CONN_DROP, &conn->flags);
1680
1681         hci_conn_put(conn);
1682
1683         skb_queue_purge(&chan->data_q);
1684         kfree(chan);
1685 }
1686
1687 void hci_chan_list_flush(struct hci_conn *conn)
1688 {
1689         struct hci_chan *chan, *n;
1690
1691         BT_DBG("hcon %p", conn);
1692
1693         list_for_each_entry_safe(chan, n, &conn->chan_list, list)
1694                 hci_chan_del(chan);
1695 }
1696
1697 static struct hci_chan *__hci_chan_lookup_handle(struct hci_conn *hcon,
1698                                                  __u16 handle)
1699 {
1700         struct hci_chan *hchan;
1701
1702         list_for_each_entry(hchan, &hcon->chan_list, list) {
1703                 if (hchan->handle == handle)
1704                         return hchan;
1705         }
1706
1707         return NULL;
1708 }
1709
1710 struct hci_chan *hci_chan_lookup_handle(struct hci_dev *hdev, __u16 handle)
1711 {
1712         struct hci_conn_hash *h = &hdev->conn_hash;
1713         struct hci_conn *hcon;
1714         struct hci_chan *hchan = NULL;
1715
1716         rcu_read_lock();
1717
1718         list_for_each_entry_rcu(hcon, &h->list, list) {
1719                 hchan = __hci_chan_lookup_handle(hcon, handle);
1720                 if (hchan)
1721                         break;
1722         }
1723
1724         rcu_read_unlock();
1725
1726         return hchan;
1727 }