2 BlueZ - Bluetooth protocol stack for Linux
4 Copyright (C) 2014 Intel Corporation
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License version 2 as
8 published by the Free Software Foundation;
10 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
11 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
12 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
13 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
14 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
15 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
20 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
21 SOFTWARE IS DISCLAIMED.
24 #include <net/bluetooth/bluetooth.h>
25 #include <net/bluetooth/hci_core.h>
28 #include "hci_request.h"
30 void hci_req_init(struct hci_request
*req
, struct hci_dev
*hdev
)
32 skb_queue_head_init(&req
->cmd_q
);
37 int hci_req_run(struct hci_request
*req
, hci_req_complete_t complete
)
39 struct hci_dev
*hdev
= req
->hdev
;
43 BT_DBG("length %u", skb_queue_len(&req
->cmd_q
));
45 /* If an error occurred during request building, remove all HCI
46 * commands queued on the HCI request queue.
49 skb_queue_purge(&req
->cmd_q
);
53 /* Do not allow empty requests */
54 if (skb_queue_empty(&req
->cmd_q
))
57 skb
= skb_peek_tail(&req
->cmd_q
);
58 bt_cb(skb
)->req
.complete
= complete
;
60 spin_lock_irqsave(&hdev
->cmd_q
.lock
, flags
);
61 skb_queue_splice_tail(&req
->cmd_q
, &hdev
->cmd_q
);
62 spin_unlock_irqrestore(&hdev
->cmd_q
.lock
, flags
);
64 queue_work(hdev
->workqueue
, &hdev
->cmd_work
);
69 struct sk_buff
*hci_prepare_cmd(struct hci_dev
*hdev
, u16 opcode
, u32 plen
,
72 int len
= HCI_COMMAND_HDR_SIZE
+ plen
;
73 struct hci_command_hdr
*hdr
;
76 skb
= bt_skb_alloc(len
, GFP_ATOMIC
);
80 hdr
= (struct hci_command_hdr
*) skb_put(skb
, HCI_COMMAND_HDR_SIZE
);
81 hdr
->opcode
= cpu_to_le16(opcode
);
85 memcpy(skb_put(skb
, plen
), param
, plen
);
87 BT_DBG("skb len %d", skb
->len
);
89 bt_cb(skb
)->pkt_type
= HCI_COMMAND_PKT
;
90 bt_cb(skb
)->opcode
= opcode
;
95 /* Queue a command to an asynchronous HCI request */
96 void hci_req_add_ev(struct hci_request
*req
, u16 opcode
, u32 plen
,
97 const void *param
, u8 event
)
99 struct hci_dev
*hdev
= req
->hdev
;
102 BT_DBG("%s opcode 0x%4.4x plen %d", hdev
->name
, opcode
, plen
);
104 /* If an error occurred during request building, there is no point in
105 * queueing the HCI command. We can simply return.
110 skb
= hci_prepare_cmd(hdev
, opcode
, plen
, param
);
112 BT_ERR("%s no memory for command (opcode 0x%4.4x)",
118 if (skb_queue_empty(&req
->cmd_q
))
119 bt_cb(skb
)->req
.start
= true;
121 bt_cb(skb
)->req
.event
= event
;
123 skb_queue_tail(&req
->cmd_q
, skb
);
126 void hci_req_add(struct hci_request
*req
, u16 opcode
, u32 plen
,
129 hci_req_add_ev(req
, opcode
, plen
, param
, 0);
132 void hci_req_add_le_scan_disable(struct hci_request
*req
)
134 struct hci_cp_le_set_scan_enable cp
;
136 memset(&cp
, 0, sizeof(cp
));
137 cp
.enable
= LE_SCAN_DISABLE
;
138 hci_req_add(req
, HCI_OP_LE_SET_SCAN_ENABLE
, sizeof(cp
), &cp
);
141 static void add_to_white_list(struct hci_request
*req
,
142 struct hci_conn_params
*params
)
144 struct hci_cp_le_add_to_white_list cp
;
146 cp
.bdaddr_type
= params
->addr_type
;
147 bacpy(&cp
.bdaddr
, ¶ms
->addr
);
149 hci_req_add(req
, HCI_OP_LE_ADD_TO_WHITE_LIST
, sizeof(cp
), &cp
);
152 static u8
update_white_list(struct hci_request
*req
)
154 struct hci_dev
*hdev
= req
->hdev
;
155 struct hci_conn_params
*params
;
156 struct bdaddr_list
*b
;
157 uint8_t white_list_entries
= 0;
159 /* Go through the current white list programmed into the
160 * controller one by one and check if that address is still
161 * in the list of pending connections or list of devices to
162 * report. If not present in either list, then queue the
163 * command to remove it from the controller.
165 list_for_each_entry(b
, &hdev
->le_white_list
, list
) {
166 struct hci_cp_le_del_from_white_list cp
;
168 if (hci_pend_le_action_lookup(&hdev
->pend_le_conns
,
169 &b
->bdaddr
, b
->bdaddr_type
) ||
170 hci_pend_le_action_lookup(&hdev
->pend_le_reports
,
171 &b
->bdaddr
, b
->bdaddr_type
)) {
172 white_list_entries
++;
176 cp
.bdaddr_type
= b
->bdaddr_type
;
177 bacpy(&cp
.bdaddr
, &b
->bdaddr
);
179 hci_req_add(req
, HCI_OP_LE_DEL_FROM_WHITE_LIST
,
183 /* Since all no longer valid white list entries have been
184 * removed, walk through the list of pending connections
185 * and ensure that any new device gets programmed into
188 * If the list of the devices is larger than the list of
189 * available white list entries in the controller, then
190 * just abort and return filer policy value to not use the
193 list_for_each_entry(params
, &hdev
->pend_le_conns
, action
) {
194 if (hci_bdaddr_list_lookup(&hdev
->le_white_list
,
195 ¶ms
->addr
, params
->addr_type
))
198 if (white_list_entries
>= hdev
->le_white_list_size
) {
199 /* Select filter policy to accept all advertising */
203 if (hci_find_irk_by_addr(hdev
, ¶ms
->addr
,
204 params
->addr_type
)) {
205 /* White list can not be used with RPAs */
209 white_list_entries
++;
210 add_to_white_list(req
, params
);
213 /* After adding all new pending connections, walk through
214 * the list of pending reports and also add these to the
215 * white list if there is still space.
217 list_for_each_entry(params
, &hdev
->pend_le_reports
, action
) {
218 if (hci_bdaddr_list_lookup(&hdev
->le_white_list
,
219 ¶ms
->addr
, params
->addr_type
))
222 if (white_list_entries
>= hdev
->le_white_list_size
) {
223 /* Select filter policy to accept all advertising */
227 if (hci_find_irk_by_addr(hdev
, ¶ms
->addr
,
228 params
->addr_type
)) {
229 /* White list can not be used with RPAs */
233 white_list_entries
++;
234 add_to_white_list(req
, params
);
237 /* Select filter policy to use white list */
241 void hci_req_add_le_passive_scan(struct hci_request
*req
)
243 struct hci_cp_le_set_scan_param param_cp
;
244 struct hci_cp_le_set_scan_enable enable_cp
;
245 struct hci_dev
*hdev
= req
->hdev
;
249 /* Set require_privacy to false since no SCAN_REQ are send
250 * during passive scanning. Not using an non-resolvable address
251 * here is important so that peer devices using direct
252 * advertising with our address will be correctly reported
255 if (hci_update_random_address(req
, false, &own_addr_type
))
258 /* Adding or removing entries from the white list must
259 * happen before enabling scanning. The controller does
260 * not allow white list modification while scanning.
262 filter_policy
= update_white_list(req
);
264 /* When the controller is using random resolvable addresses and
265 * with that having LE privacy enabled, then controllers with
266 * Extended Scanner Filter Policies support can now enable support
267 * for handling directed advertising.
269 * So instead of using filter polices 0x00 (no whitelist)
270 * and 0x01 (whitelist enabled) use the new filter policies
271 * 0x02 (no whitelist) and 0x03 (whitelist enabled).
273 if (test_bit(HCI_PRIVACY
, &hdev
->dev_flags
) &&
274 (hdev
->le_features
[0] & HCI_LE_EXT_SCAN_POLICY
))
275 filter_policy
|= 0x02;
277 memset(¶m_cp
, 0, sizeof(param_cp
));
278 param_cp
.type
= LE_SCAN_PASSIVE
;
279 param_cp
.interval
= cpu_to_le16(hdev
->le_scan_interval
);
280 param_cp
.window
= cpu_to_le16(hdev
->le_scan_window
);
281 param_cp
.own_address_type
= own_addr_type
;
282 param_cp
.filter_policy
= filter_policy
;
283 hci_req_add(req
, HCI_OP_LE_SET_SCAN_PARAM
, sizeof(param_cp
),
286 memset(&enable_cp
, 0, sizeof(enable_cp
));
287 enable_cp
.enable
= LE_SCAN_ENABLE
;
288 enable_cp
.filter_dup
= LE_SCAN_FILTER_DUP_ENABLE
;
289 hci_req_add(req
, HCI_OP_LE_SET_SCAN_ENABLE
, sizeof(enable_cp
),
293 static void set_random_addr(struct hci_request
*req
, bdaddr_t
*rpa
)
295 struct hci_dev
*hdev
= req
->hdev
;
297 /* If we're advertising or initiating an LE connection we can't
298 * go ahead and change the random address at this time. This is
299 * because the eventual initiator address used for the
300 * subsequently created connection will be undefined (some
301 * controllers use the new address and others the one we had
302 * when the operation started).
304 * In this kind of scenario skip the update and let the random
305 * address be updated at the next cycle.
307 if (test_bit(HCI_LE_ADV
, &hdev
->dev_flags
) ||
308 hci_conn_hash_lookup_state(hdev
, LE_LINK
, BT_CONNECT
)) {
309 BT_DBG("Deferring random address update");
310 set_bit(HCI_RPA_EXPIRED
, &hdev
->dev_flags
);
314 hci_req_add(req
, HCI_OP_LE_SET_RANDOM_ADDR
, 6, rpa
);
317 int hci_update_random_address(struct hci_request
*req
, bool require_privacy
,
320 struct hci_dev
*hdev
= req
->hdev
;
323 /* If privacy is enabled use a resolvable private address. If
324 * current RPA has expired or there is something else than
325 * the current RPA in use, then generate a new one.
327 if (test_bit(HCI_PRIVACY
, &hdev
->dev_flags
)) {
330 *own_addr_type
= ADDR_LE_DEV_RANDOM
;
332 if (!test_and_clear_bit(HCI_RPA_EXPIRED
, &hdev
->dev_flags
) &&
333 !bacmp(&hdev
->random_addr
, &hdev
->rpa
))
336 err
= smp_generate_rpa(hdev
, hdev
->irk
, &hdev
->rpa
);
338 BT_ERR("%s failed to generate new RPA", hdev
->name
);
342 set_random_addr(req
, &hdev
->rpa
);
344 to
= msecs_to_jiffies(hdev
->rpa_timeout
* 1000);
345 queue_delayed_work(hdev
->workqueue
, &hdev
->rpa_expired
, to
);
350 /* In case of required privacy without resolvable private address,
351 * use an non-resolvable private address. This is useful for active
352 * scanning and non-connectable advertising.
354 if (require_privacy
) {
358 /* The non-resolvable private address is generated
359 * from random six bytes with the two most significant
362 get_random_bytes(&nrpa
, 6);
365 /* The non-resolvable private address shall not be
366 * equal to the public address.
368 if (bacmp(&hdev
->bdaddr
, &nrpa
))
372 *own_addr_type
= ADDR_LE_DEV_RANDOM
;
373 set_random_addr(req
, &nrpa
);
377 /* If forcing static address is in use or there is no public
378 * address use the static address as random address (but skip
379 * the HCI command if the current random address is already the
382 * In case BR/EDR has been disabled on a dual-mode controller
383 * and a static address has been configured, then use that
384 * address instead of the public BR/EDR address.
386 if (test_bit(HCI_FORCE_STATIC_ADDR
, &hdev
->dbg_flags
) ||
387 !bacmp(&hdev
->bdaddr
, BDADDR_ANY
) ||
388 (!test_bit(HCI_BREDR_ENABLED
, &hdev
->dev_flags
) &&
389 bacmp(&hdev
->static_addr
, BDADDR_ANY
))) {
390 *own_addr_type
= ADDR_LE_DEV_RANDOM
;
391 if (bacmp(&hdev
->static_addr
, &hdev
->random_addr
))
392 hci_req_add(req
, HCI_OP_LE_SET_RANDOM_ADDR
, 6,
397 /* Neither privacy nor static address is being used so use a
400 *own_addr_type
= ADDR_LE_DEV_PUBLIC
;
405 static bool disconnected_whitelist_entries(struct hci_dev
*hdev
)
407 struct bdaddr_list
*b
;
409 list_for_each_entry(b
, &hdev
->whitelist
, list
) {
410 struct hci_conn
*conn
;
412 conn
= hci_conn_hash_lookup_ba(hdev
, ACL_LINK
, &b
->bdaddr
);
416 if (conn
->state
!= BT_CONNECTED
&& conn
->state
!= BT_CONFIG
)
423 void __hci_update_page_scan(struct hci_request
*req
)
425 struct hci_dev
*hdev
= req
->hdev
;
428 if (!test_bit(HCI_BREDR_ENABLED
, &hdev
->dev_flags
))
431 if (!hdev_is_powered(hdev
))
434 if (mgmt_powering_down(hdev
))
437 if (test_bit(HCI_CONNECTABLE
, &hdev
->dev_flags
) ||
438 disconnected_whitelist_entries(hdev
))
441 scan
= SCAN_DISABLED
;
443 if (test_bit(HCI_PSCAN
, &hdev
->flags
) == !!(scan
& SCAN_PAGE
))
446 if (test_bit(HCI_DISCOVERABLE
, &hdev
->dev_flags
))
447 scan
|= SCAN_INQUIRY
;
449 hci_req_add(req
, HCI_OP_WRITE_SCAN_ENABLE
, 1, &scan
);
452 void hci_update_page_scan(struct hci_dev
*hdev
)
454 struct hci_request req
;
456 hci_req_init(&req
, hdev
);
457 __hci_update_page_scan(&req
);
458 hci_req_run(&req
, NULL
);
461 /* This function controls the background scanning based on hdev->pend_le_conns
462 * list. If there are pending LE connection we start the background scanning,
463 * otherwise we stop it.
465 * This function requires the caller holds hdev->lock.
467 void __hci_update_background_scan(struct hci_request
*req
)
469 struct hci_dev
*hdev
= req
->hdev
;
470 struct hci_conn
*conn
;
472 if (!test_bit(HCI_UP
, &hdev
->flags
) ||
473 test_bit(HCI_INIT
, &hdev
->flags
) ||
474 test_bit(HCI_SETUP
, &hdev
->dev_flags
) ||
475 test_bit(HCI_CONFIG
, &hdev
->dev_flags
) ||
476 test_bit(HCI_AUTO_OFF
, &hdev
->dev_flags
) ||
477 test_bit(HCI_UNREGISTER
, &hdev
->dev_flags
))
480 /* No point in doing scanning if LE support hasn't been enabled */
481 if (!test_bit(HCI_LE_ENABLED
, &hdev
->dev_flags
))
484 /* If discovery is active don't interfere with it */
485 if (hdev
->discovery
.state
!= DISCOVERY_STOPPED
)
488 /* Reset RSSI and UUID filters when starting background scanning
489 * since these filters are meant for service discovery only.
491 * The Start Discovery and Start Service Discovery operations
492 * ensure to set proper values for RSSI threshold and UUID
493 * filter list. So it is safe to just reset them here.
495 hci_discovery_filter_clear(hdev
);
497 if (list_empty(&hdev
->pend_le_conns
) &&
498 list_empty(&hdev
->pend_le_reports
)) {
499 /* If there is no pending LE connections or devices
500 * to be scanned for, we should stop the background
504 /* If controller is not scanning we are done. */
505 if (!test_bit(HCI_LE_SCAN
, &hdev
->dev_flags
))
508 hci_req_add_le_scan_disable(req
);
510 BT_DBG("%s stopping background scanning", hdev
->name
);
512 /* If there is at least one pending LE connection, we should
513 * keep the background scan running.
516 /* If controller is connecting, we should not start scanning
517 * since some controllers are not able to scan and connect at
520 conn
= hci_conn_hash_lookup_state(hdev
, LE_LINK
, BT_CONNECT
);
524 /* If controller is currently scanning, we stop it to ensure we
525 * don't miss any advertising (due to duplicates filter).
527 if (test_bit(HCI_LE_SCAN
, &hdev
->dev_flags
))
528 hci_req_add_le_scan_disable(req
);
530 hci_req_add_le_passive_scan(req
);
532 BT_DBG("%s starting background scanning", hdev
->name
);
536 static void update_background_scan_complete(struct hci_dev
*hdev
, u8 status
,
540 BT_DBG("HCI request failed to update background scanning: "
541 "status 0x%2.2x", status
);
544 void hci_update_background_scan(struct hci_dev
*hdev
)
547 struct hci_request req
;
549 hci_req_init(&req
, hdev
);
551 __hci_update_background_scan(&req
);
553 err
= hci_req_run(&req
, update_background_scan_complete
);
554 if (err
&& err
!= -ENODATA
)
555 BT_ERR("Failed to run HCI request: err %d", err
);