Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
[linux-2.6] / net / bluetooth / hci_conn.c
1 /*
2    BlueZ - Bluetooth protocol stack for Linux
3    Copyright (C) 2000-2001 Qualcomm Incorporated
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/module.h>
28
29 #include <linux/types.h>
30 #include <linux/errno.h>
31 #include <linux/kernel.h>
32 #include <linux/slab.h>
33 #include <linux/poll.h>
34 #include <linux/fcntl.h>
35 #include <linux/init.h>
36 #include <linux/skbuff.h>
37 #include <linux/interrupt.h>
38 #include <linux/notifier.h>
39 #include <net/sock.h>
40
41 #include <asm/system.h>
42 #include <asm/uaccess.h>
43 #include <asm/unaligned.h>
44
45 #include <net/bluetooth/bluetooth.h>
46 #include <net/bluetooth/hci_core.h>
47
48 void hci_acl_connect(struct hci_conn *conn)
49 {
50         struct hci_dev *hdev = conn->hdev;
51         struct inquiry_entry *ie;
52         struct hci_cp_create_conn cp;
53
54         BT_DBG("%p", conn);
55
56         conn->state = BT_CONNECT;
57         conn->out = 1;
58
59         conn->link_mode = HCI_LM_MASTER;
60
61         conn->attempt++;
62
63         conn->link_policy = hdev->link_policy;
64
65         memset(&cp, 0, sizeof(cp));
66         bacpy(&cp.bdaddr, &conn->dst);
67         cp.pscan_rep_mode = 0x02;
68
69         if ((ie = hci_inquiry_cache_lookup(hdev, &conn->dst))) {
70                 if (inquiry_entry_age(ie) <= INQUIRY_ENTRY_AGE_MAX) {
71                         cp.pscan_rep_mode = ie->data.pscan_rep_mode;
72                         cp.pscan_mode     = ie->data.pscan_mode;
73                         cp.clock_offset   = ie->data.clock_offset |
74                                                         cpu_to_le16(0x8000);
75                 }
76
77                 memcpy(conn->dev_class, ie->data.dev_class, 3);
78                 conn->ssp_mode = ie->data.ssp_mode;
79         }
80
81         cp.pkt_type = cpu_to_le16(conn->pkt_type);
82         if (lmp_rswitch_capable(hdev) && !(hdev->link_mode & HCI_LM_MASTER))
83                 cp.role_switch = 0x01;
84         else
85                 cp.role_switch = 0x00;
86
87         hci_send_cmd(hdev, HCI_OP_CREATE_CONN, sizeof(cp), &cp);
88 }
89
90 static void hci_acl_connect_cancel(struct hci_conn *conn)
91 {
92         struct hci_cp_create_conn_cancel cp;
93
94         BT_DBG("%p", conn);
95
96         if (conn->hdev->hci_ver < 2)
97                 return;
98
99         bacpy(&cp.bdaddr, &conn->dst);
100         hci_send_cmd(conn->hdev, HCI_OP_CREATE_CONN_CANCEL, sizeof(cp), &cp);
101 }
102
103 void hci_acl_disconn(struct hci_conn *conn, __u8 reason)
104 {
105         struct hci_cp_disconnect cp;
106
107         BT_DBG("%p", conn);
108
109         conn->state = BT_DISCONN;
110
111         cp.handle = cpu_to_le16(conn->handle);
112         cp.reason = reason;
113         hci_send_cmd(conn->hdev, HCI_OP_DISCONNECT, sizeof(cp), &cp);
114 }
115
116 void hci_add_sco(struct hci_conn *conn, __u16 handle)
117 {
118         struct hci_dev *hdev = conn->hdev;
119         struct hci_cp_add_sco cp;
120
121         BT_DBG("%p", conn);
122
123         conn->state = BT_CONNECT;
124         conn->out = 1;
125
126         conn->attempt++;
127
128         cp.handle   = cpu_to_le16(handle);
129         cp.pkt_type = cpu_to_le16(conn->pkt_type);
130
131         hci_send_cmd(hdev, HCI_OP_ADD_SCO, sizeof(cp), &cp);
132 }
133
134 void hci_setup_sync(struct hci_conn *conn, __u16 handle)
135 {
136         struct hci_dev *hdev = conn->hdev;
137         struct hci_cp_setup_sync_conn cp;
138
139         BT_DBG("%p", conn);
140
141         conn->state = BT_CONNECT;
142         conn->out = 1;
143
144         conn->attempt++;
145
146         cp.handle   = cpu_to_le16(handle);
147         cp.pkt_type = cpu_to_le16(conn->pkt_type);
148
149         cp.tx_bandwidth   = cpu_to_le32(0x00001f40);
150         cp.rx_bandwidth   = cpu_to_le32(0x00001f40);
151         cp.max_latency    = cpu_to_le16(0xffff);
152         cp.voice_setting  = cpu_to_le16(hdev->voice_setting);
153         cp.retrans_effort = 0xff;
154
155         hci_send_cmd(hdev, HCI_OP_SETUP_SYNC_CONN, sizeof(cp), &cp);
156 }
157
158 static void hci_conn_timeout(unsigned long arg)
159 {
160         struct hci_conn *conn = (void *) arg;
161         struct hci_dev *hdev = conn->hdev;
162         __u8 reason;
163
164         BT_DBG("conn %p state %d", conn, conn->state);
165
166         if (atomic_read(&conn->refcnt))
167                 return;
168
169         hci_dev_lock(hdev);
170
171         switch (conn->state) {
172         case BT_CONNECT:
173         case BT_CONNECT2:
174                 if (conn->type == ACL_LINK)
175                         hci_acl_connect_cancel(conn);
176                 else
177                         hci_acl_disconn(conn, 0x13);
178                 break;
179         case BT_CONFIG:
180         case BT_CONNECTED:
181                 reason = hci_proto_disconn_ind(conn);
182                 hci_acl_disconn(conn, reason);
183                 break;
184         default:
185                 conn->state = BT_CLOSED;
186                 break;
187         }
188
189         hci_dev_unlock(hdev);
190 }
191
192 static void hci_conn_idle(unsigned long arg)
193 {
194         struct hci_conn *conn = (void *) arg;
195
196         BT_DBG("conn %p mode %d", conn, conn->mode);
197
198         hci_conn_enter_sniff_mode(conn);
199 }
200
201 struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst)
202 {
203         struct hci_conn *conn;
204
205         BT_DBG("%s dst %s", hdev->name, batostr(dst));
206
207         conn = kzalloc(sizeof(struct hci_conn), GFP_ATOMIC);
208         if (!conn)
209                 return NULL;
210
211         bacpy(&conn->dst, dst);
212         conn->hdev  = hdev;
213         conn->type  = type;
214         conn->mode  = HCI_CM_ACTIVE;
215         conn->state = BT_OPEN;
216
217         conn->power_save = 1;
218
219         switch (type) {
220         case ACL_LINK:
221                 conn->pkt_type = hdev->pkt_type & ACL_PTYPE_MASK;
222                 break;
223         case SCO_LINK:
224                 if (lmp_esco_capable(hdev))
225                         conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
226                                         (hdev->esco_type & EDR_ESCO_MASK);
227                 else
228                         conn->pkt_type = hdev->pkt_type & SCO_PTYPE_MASK;
229                 break;
230         case ESCO_LINK:
231                 conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
232                 break;
233         }
234
235         skb_queue_head_init(&conn->data_q);
236
237         setup_timer(&conn->disc_timer, hci_conn_timeout, (unsigned long)conn);
238         setup_timer(&conn->idle_timer, hci_conn_idle, (unsigned long)conn);
239
240         atomic_set(&conn->refcnt, 0);
241
242         hci_dev_hold(hdev);
243
244         tasklet_disable(&hdev->tx_task);
245
246         hci_conn_hash_add(hdev, conn);
247         if (hdev->notify)
248                 hdev->notify(hdev, HCI_NOTIFY_CONN_ADD);
249
250         tasklet_enable(&hdev->tx_task);
251
252         return conn;
253 }
254
255 int hci_conn_del(struct hci_conn *conn)
256 {
257         struct hci_dev *hdev = conn->hdev;
258
259         BT_DBG("%s conn %p handle %d", hdev->name, conn, conn->handle);
260
261         del_timer(&conn->idle_timer);
262
263         del_timer(&conn->disc_timer);
264
265         if (conn->type == ACL_LINK) {
266                 struct hci_conn *sco = conn->link;
267                 if (sco)
268                         sco->link = NULL;
269
270                 /* Unacked frames */
271                 hdev->acl_cnt += conn->sent;
272         } else {
273                 struct hci_conn *acl = conn->link;
274                 if (acl) {
275                         acl->link = NULL;
276                         hci_conn_put(acl);
277                 }
278         }
279
280         tasklet_disable(&hdev->tx_task);
281
282         hci_conn_hash_del(hdev, conn);
283         if (hdev->notify)
284                 hdev->notify(hdev, HCI_NOTIFY_CONN_DEL);
285
286         tasklet_enable(&hdev->tx_task);
287
288         skb_queue_purge(&conn->data_q);
289
290         hci_conn_del_sysfs(conn);
291
292         return 0;
293 }
294
295 struct hci_dev *hci_get_route(bdaddr_t *dst, bdaddr_t *src)
296 {
297         int use_src = bacmp(src, BDADDR_ANY);
298         struct hci_dev *hdev = NULL;
299         struct list_head *p;
300
301         BT_DBG("%s -> %s", batostr(src), batostr(dst));
302
303         read_lock_bh(&hci_dev_list_lock);
304
305         list_for_each(p, &hci_dev_list) {
306                 struct hci_dev *d = list_entry(p, struct hci_dev, list);
307
308                 if (!test_bit(HCI_UP, &d->flags) || test_bit(HCI_RAW, &d->flags))
309                         continue;
310
311                 /* Simple routing:
312                  *   No source address - find interface with bdaddr != dst
313                  *   Source address    - find interface with bdaddr == src
314                  */
315
316                 if (use_src) {
317                         if (!bacmp(&d->bdaddr, src)) {
318                                 hdev = d; break;
319                         }
320                 } else {
321                         if (bacmp(&d->bdaddr, dst)) {
322                                 hdev = d; break;
323                         }
324                 }
325         }
326
327         if (hdev)
328                 hdev = hci_dev_hold(hdev);
329
330         read_unlock_bh(&hci_dev_list_lock);
331         return hdev;
332 }
333 EXPORT_SYMBOL(hci_get_route);
334
335 /* Create SCO or ACL connection.
336  * Device _must_ be locked */
337 struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8 sec_level, __u8 auth_type)
338 {
339         struct hci_conn *acl;
340         struct hci_conn *sco;
341
342         BT_DBG("%s dst %s", hdev->name, batostr(dst));
343
344         if (!(acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst))) {
345                 if (!(acl = hci_conn_add(hdev, ACL_LINK, dst)))
346                         return NULL;
347         }
348
349         hci_conn_hold(acl);
350
351         if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
352                 acl->sec_level = sec_level;
353                 acl->auth_type = auth_type;
354                 hci_acl_connect(acl);
355         }
356
357         if (type == ACL_LINK)
358                 return acl;
359
360         if (!(sco = hci_conn_hash_lookup_ba(hdev, type, dst))) {
361                 if (!(sco = hci_conn_add(hdev, type, dst))) {
362                         hci_conn_put(acl);
363                         return NULL;
364                 }
365         }
366
367         acl->link = sco;
368         sco->link = acl;
369
370         hci_conn_hold(sco);
371
372         if (acl->state == BT_CONNECTED &&
373                         (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
374                 if (lmp_esco_capable(hdev))
375                         hci_setup_sync(sco, acl->handle);
376                 else
377                         hci_add_sco(sco, acl->handle);
378         }
379
380         return sco;
381 }
382 EXPORT_SYMBOL(hci_connect);
383
384 /* Check link security requirement */
385 int hci_conn_check_link_mode(struct hci_conn *conn)
386 {
387         BT_DBG("conn %p", conn);
388
389         if (conn->ssp_mode > 0 && conn->hdev->ssp_mode > 0 &&
390                                         !(conn->link_mode & HCI_LM_ENCRYPT))
391                 return 0;
392
393         return 1;
394 }
395 EXPORT_SYMBOL(hci_conn_check_link_mode);
396
397 /* Authenticate remote device */
398 static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
399 {
400         BT_DBG("conn %p", conn);
401
402         if (sec_level > conn->sec_level)
403                 conn->sec_level = sec_level;
404         else if (conn->link_mode & HCI_LM_AUTH)
405                 return 1;
406
407         conn->auth_type = auth_type;
408
409         if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->pend)) {
410                 struct hci_cp_auth_requested cp;
411                 cp.handle = cpu_to_le16(conn->handle);
412                 hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
413                                                         sizeof(cp), &cp);
414         }
415
416         return 0;
417 }
418
419 /* Enable security */
420 int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
421 {
422         BT_DBG("conn %p", conn);
423
424         if (sec_level == BT_SECURITY_SDP)
425                 return 1;
426
427         if (sec_level == BT_SECURITY_LOW) {
428                 if (conn->ssp_mode > 0 && conn->hdev->ssp_mode > 0)
429                         return hci_conn_auth(conn, sec_level, auth_type);
430                 else
431                         return 1;
432         }
433
434         if (conn->link_mode & HCI_LM_ENCRYPT)
435                 return hci_conn_auth(conn, sec_level, auth_type);
436
437         if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->pend))
438                 return 0;
439
440         if (hci_conn_auth(conn, sec_level, auth_type)) {
441                 struct hci_cp_set_conn_encrypt cp;
442                 cp.handle  = cpu_to_le16(conn->handle);
443                 cp.encrypt = 1;
444                 hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT,
445                                                         sizeof(cp), &cp);
446         }
447
448         return 0;
449 }
450 EXPORT_SYMBOL(hci_conn_security);
451
452 /* Change link key */
453 int hci_conn_change_link_key(struct hci_conn *conn)
454 {
455         BT_DBG("conn %p", conn);
456
457         if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->pend)) {
458                 struct hci_cp_change_conn_link_key cp;
459                 cp.handle = cpu_to_le16(conn->handle);
460                 hci_send_cmd(conn->hdev, HCI_OP_CHANGE_CONN_LINK_KEY,
461                                                         sizeof(cp), &cp);
462         }
463
464         return 0;
465 }
466 EXPORT_SYMBOL(hci_conn_change_link_key);
467
468 /* Switch role */
469 int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
470 {
471         BT_DBG("conn %p", conn);
472
473         if (!role && conn->link_mode & HCI_LM_MASTER)
474                 return 1;
475
476         if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->pend)) {
477                 struct hci_cp_switch_role cp;
478                 bacpy(&cp.bdaddr, &conn->dst);
479                 cp.role = role;
480                 hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
481         }
482
483         return 0;
484 }
485 EXPORT_SYMBOL(hci_conn_switch_role);
486
487 /* Enter active mode */
488 void hci_conn_enter_active_mode(struct hci_conn *conn)
489 {
490         struct hci_dev *hdev = conn->hdev;
491
492         BT_DBG("conn %p mode %d", conn, conn->mode);
493
494         if (test_bit(HCI_RAW, &hdev->flags))
495                 return;
496
497         if (conn->mode != HCI_CM_SNIFF || !conn->power_save)
498                 goto timer;
499
500         if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->pend)) {
501                 struct hci_cp_exit_sniff_mode cp;
502                 cp.handle = cpu_to_le16(conn->handle);
503                 hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
504         }
505
506 timer:
507         if (hdev->idle_timeout > 0)
508                 mod_timer(&conn->idle_timer,
509                         jiffies + msecs_to_jiffies(hdev->idle_timeout));
510 }
511
512 /* Enter sniff mode */
513 void hci_conn_enter_sniff_mode(struct hci_conn *conn)
514 {
515         struct hci_dev *hdev = conn->hdev;
516
517         BT_DBG("conn %p mode %d", conn, conn->mode);
518
519         if (test_bit(HCI_RAW, &hdev->flags))
520                 return;
521
522         if (!lmp_sniff_capable(hdev) || !lmp_sniff_capable(conn))
523                 return;
524
525         if (conn->mode != HCI_CM_ACTIVE || !(conn->link_policy & HCI_LP_SNIFF))
526                 return;
527
528         if (lmp_sniffsubr_capable(hdev) && lmp_sniffsubr_capable(conn)) {
529                 struct hci_cp_sniff_subrate cp;
530                 cp.handle             = cpu_to_le16(conn->handle);
531                 cp.max_latency        = cpu_to_le16(0);
532                 cp.min_remote_timeout = cpu_to_le16(0);
533                 cp.min_local_timeout  = cpu_to_le16(0);
534                 hci_send_cmd(hdev, HCI_OP_SNIFF_SUBRATE, sizeof(cp), &cp);
535         }
536
537         if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->pend)) {
538                 struct hci_cp_sniff_mode cp;
539                 cp.handle       = cpu_to_le16(conn->handle);
540                 cp.max_interval = cpu_to_le16(hdev->sniff_max_interval);
541                 cp.min_interval = cpu_to_le16(hdev->sniff_min_interval);
542                 cp.attempt      = cpu_to_le16(4);
543                 cp.timeout      = cpu_to_le16(1);
544                 hci_send_cmd(hdev, HCI_OP_SNIFF_MODE, sizeof(cp), &cp);
545         }
546 }
547
548 /* Drop all connection on the device */
549 void hci_conn_hash_flush(struct hci_dev *hdev)
550 {
551         struct hci_conn_hash *h = &hdev->conn_hash;
552         struct list_head *p;
553
554         BT_DBG("hdev %s", hdev->name);
555
556         p = h->list.next;
557         while (p != &h->list) {
558                 struct hci_conn *c;
559
560                 c = list_entry(p, struct hci_conn, list);
561                 p = p->next;
562
563                 c->state = BT_CLOSED;
564
565                 hci_proto_disconn_cfm(c, 0x16);
566                 hci_conn_del(c);
567         }
568 }
569
570 /* Check pending connect attempts */
571 void hci_conn_check_pending(struct hci_dev *hdev)
572 {
573         struct hci_conn *conn;
574
575         BT_DBG("hdev %s", hdev->name);
576
577         hci_dev_lock(hdev);
578
579         conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
580         if (conn)
581                 hci_acl_connect(conn);
582
583         hci_dev_unlock(hdev);
584 }
585
586 int hci_get_conn_list(void __user *arg)
587 {
588         struct hci_conn_list_req req, *cl;
589         struct hci_conn_info *ci;
590         struct hci_dev *hdev;
591         struct list_head *p;
592         int n = 0, size, err;
593
594         if (copy_from_user(&req, arg, sizeof(req)))
595                 return -EFAULT;
596
597         if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
598                 return -EINVAL;
599
600         size = sizeof(req) + req.conn_num * sizeof(*ci);
601
602         if (!(cl = kmalloc(size, GFP_KERNEL)))
603                 return -ENOMEM;
604
605         if (!(hdev = hci_dev_get(req.dev_id))) {
606                 kfree(cl);
607                 return -ENODEV;
608         }
609
610         ci = cl->conn_info;
611
612         hci_dev_lock_bh(hdev);
613         list_for_each(p, &hdev->conn_hash.list) {
614                 register struct hci_conn *c;
615                 c = list_entry(p, struct hci_conn, list);
616
617                 bacpy(&(ci + n)->bdaddr, &c->dst);
618                 (ci + n)->handle = c->handle;
619                 (ci + n)->type  = c->type;
620                 (ci + n)->out   = c->out;
621                 (ci + n)->state = c->state;
622                 (ci + n)->link_mode = c->link_mode;
623                 if (++n >= req.conn_num)
624                         break;
625         }
626         hci_dev_unlock_bh(hdev);
627
628         cl->dev_id = hdev->id;
629         cl->conn_num = n;
630         size = sizeof(req) + n * sizeof(*ci);
631
632         hci_dev_put(hdev);
633
634         err = copy_to_user(arg, cl, size);
635         kfree(cl);
636
637         return err ? -EFAULT : 0;
638 }
639
640 int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
641 {
642         struct hci_conn_info_req req;
643         struct hci_conn_info ci;
644         struct hci_conn *conn;
645         char __user *ptr = arg + sizeof(req);
646
647         if (copy_from_user(&req, arg, sizeof(req)))
648                 return -EFAULT;
649
650         hci_dev_lock_bh(hdev);
651         conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
652         if (conn) {
653                 bacpy(&ci.bdaddr, &conn->dst);
654                 ci.handle = conn->handle;
655                 ci.type  = conn->type;
656                 ci.out   = conn->out;
657                 ci.state = conn->state;
658                 ci.link_mode = conn->link_mode;
659         }
660         hci_dev_unlock_bh(hdev);
661
662         if (!conn)
663                 return -ENOENT;
664
665         return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
666 }
667
668 int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
669 {
670         struct hci_auth_info_req req;
671         struct hci_conn *conn;
672
673         if (copy_from_user(&req, arg, sizeof(req)))
674                 return -EFAULT;
675
676         hci_dev_lock_bh(hdev);
677         conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
678         if (conn)
679                 req.type = conn->auth_type;
680         hci_dev_unlock_bh(hdev);
681
682         if (!conn)
683                 return -ENOENT;
684
685         return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
686 }