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Diffstat (limited to 'net/bluetooth/hci_request.c')
-rw-r--r--net/bluetooth/hci_request.c556
1 files changed, 556 insertions, 0 deletions
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
new file mode 100644
index 000000000000..b59f92c6df0c
--- /dev/null
+++ b/net/bluetooth/hci_request.c
@@ -0,0 +1,556 @@
+/*
+ BlueZ - Bluetooth protocol stack for Linux
+
+ Copyright (C) 2014 Intel Corporation
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License version 2 as
+ published by the Free Software Foundation;
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+ IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
+ CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
+ WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+ ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
+ COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
+ SOFTWARE IS DISCLAIMED.
+*/
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#include "smp.h"
+#include "hci_request.h"
+
+void hci_req_init(struct hci_request *req, struct hci_dev *hdev)
+{
+ skb_queue_head_init(&req->cmd_q);
+ req->hdev = hdev;
+ req->err = 0;
+}
+
+int hci_req_run(struct hci_request *req, hci_req_complete_t complete)
+{
+ struct hci_dev *hdev = req->hdev;
+ struct sk_buff *skb;
+ unsigned long flags;
+
+ BT_DBG("length %u", skb_queue_len(&req->cmd_q));
+
+ /* If an error occurred during request building, remove all HCI
+ * commands queued on the HCI request queue.
+ */
+ if (req->err) {
+ skb_queue_purge(&req->cmd_q);
+ return req->err;
+ }
+
+ /* Do not allow empty requests */
+ if (skb_queue_empty(&req->cmd_q))
+ return -ENODATA;
+
+ skb = skb_peek_tail(&req->cmd_q);
+ bt_cb(skb)->req.complete = complete;
+
+ spin_lock_irqsave(&hdev->cmd_q.lock, flags);
+ skb_queue_splice_tail(&req->cmd_q, &hdev->cmd_q);
+ spin_unlock_irqrestore(&hdev->cmd_q.lock, flags);
+
+ queue_work(hdev->workqueue, &hdev->cmd_work);
+
+ return 0;
+}
+
+struct sk_buff *hci_prepare_cmd(struct hci_dev *hdev, u16 opcode, u32 plen,
+ const void *param)
+{
+ int len = HCI_COMMAND_HDR_SIZE + plen;
+ struct hci_command_hdr *hdr;
+ struct sk_buff *skb;
+
+ skb = bt_skb_alloc(len, GFP_ATOMIC);
+ if (!skb)
+ return NULL;
+
+ hdr = (struct hci_command_hdr *) skb_put(skb, HCI_COMMAND_HDR_SIZE);
+ hdr->opcode = cpu_to_le16(opcode);
+ hdr->plen = plen;
+
+ if (plen)
+ memcpy(skb_put(skb, plen), param, plen);
+
+ BT_DBG("skb len %d", skb->len);
+
+ bt_cb(skb)->pkt_type = HCI_COMMAND_PKT;
+ bt_cb(skb)->opcode = opcode;
+
+ return skb;
+}
+
+/* Queue a command to an asynchronous HCI request */
+void hci_req_add_ev(struct hci_request *req, u16 opcode, u32 plen,
+ const void *param, u8 event)
+{
+ struct hci_dev *hdev = req->hdev;
+ struct sk_buff *skb;
+
+ BT_DBG("%s opcode 0x%4.4x plen %d", hdev->name, opcode, plen);
+
+ /* If an error occurred during request building, there is no point in
+ * queueing the HCI command. We can simply return.
+ */
+ if (req->err)
+ return;
+
+ skb = hci_prepare_cmd(hdev, opcode, plen, param);
+ if (!skb) {
+ BT_ERR("%s no memory for command (opcode 0x%4.4x)",
+ hdev->name, opcode);
+ req->err = -ENOMEM;
+ return;
+ }
+
+ if (skb_queue_empty(&req->cmd_q))
+ bt_cb(skb)->req.start = true;
+
+ bt_cb(skb)->req.event = event;
+
+ skb_queue_tail(&req->cmd_q, skb);
+}
+
+void hci_req_add(struct hci_request *req, u16 opcode, u32 plen,
+ const void *param)
+{
+ hci_req_add_ev(req, opcode, plen, param, 0);
+}
+
+void hci_req_add_le_scan_disable(struct hci_request *req)
+{
+ struct hci_cp_le_set_scan_enable cp;
+
+ memset(&cp, 0, sizeof(cp));
+ cp.enable = LE_SCAN_DISABLE;
+ hci_req_add(req, HCI_OP_LE_SET_SCAN_ENABLE, sizeof(cp), &cp);
+}
+
+static void add_to_white_list(struct hci_request *req,
+ struct hci_conn_params *params)
+{
+ struct hci_cp_le_add_to_white_list cp;
+
+ cp.bdaddr_type = params->addr_type;
+ bacpy(&cp.bdaddr, &params->addr);
+
+ hci_req_add(req, HCI_OP_LE_ADD_TO_WHITE_LIST, sizeof(cp), &cp);
+}
+
+static u8 update_white_list(struct hci_request *req)
+{
+ struct hci_dev *hdev = req->hdev;
+ struct hci_conn_params *params;
+ struct bdaddr_list *b;
+ uint8_t white_list_entries = 0;
+
+ /* Go through the current white list programmed into the
+ * controller one by one and check if that address is still
+ * in the list of pending connections or list of devices to
+ * report. If not present in either list, then queue the
+ * command to remove it from the controller.
+ */
+ list_for_each_entry(b, &hdev->le_white_list, list) {
+ struct hci_cp_le_del_from_white_list cp;
+
+ if (hci_pend_le_action_lookup(&hdev->pend_le_conns,
+ &b->bdaddr, b->bdaddr_type) ||
+ hci_pend_le_action_lookup(&hdev->pend_le_reports,
+ &b->bdaddr, b->bdaddr_type)) {
+ white_list_entries++;
+ continue;
+ }
+
+ cp.bdaddr_type = b->bdaddr_type;
+ bacpy(&cp.bdaddr, &b->bdaddr);
+
+ hci_req_add(req, HCI_OP_LE_DEL_FROM_WHITE_LIST,
+ sizeof(cp), &cp);
+ }
+
+ /* Since all no longer valid white list entries have been
+ * removed, walk through the list of pending connections
+ * and ensure that any new device gets programmed into
+ * the controller.
+ *
+ * If the list of the devices is larger than the list of
+ * available white list entries in the controller, then
+ * just abort and return filer policy value to not use the
+ * white list.
+ */
+ list_for_each_entry(params, &hdev->pend_le_conns, action) {
+ if (hci_bdaddr_list_lookup(&hdev->le_white_list,
+ &params->addr, params->addr_type))
+ continue;
+
+ if (white_list_entries >= hdev->le_white_list_size) {
+ /* Select filter policy to accept all advertising */
+ return 0x00;
+ }
+
+ if (hci_find_irk_by_addr(hdev, &params->addr,
+ params->addr_type)) {
+ /* White list can not be used with RPAs */
+ return 0x00;
+ }
+
+ white_list_entries++;
+ add_to_white_list(req, params);
+ }
+
+ /* After adding all new pending connections, walk through
+ * the list of pending reports and also add these to the
+ * white list if there is still space.
+ */
+ list_for_each_entry(params, &hdev->pend_le_reports, action) {
+ if (hci_bdaddr_list_lookup(&hdev->le_white_list,
+ &params->addr, params->addr_type))
+ continue;
+
+ if (white_list_entries >= hdev->le_white_list_size) {
+ /* Select filter policy to accept all advertising */
+ return 0x00;
+ }
+
+ if (hci_find_irk_by_addr(hdev, &params->addr,
+ params->addr_type)) {
+ /* White list can not be used with RPAs */
+ return 0x00;
+ }
+
+ white_list_entries++;
+ add_to_white_list(req, params);
+ }
+
+ /* Select filter policy to use white list */
+ return 0x01;
+}
+
+void hci_req_add_le_passive_scan(struct hci_request *req)
+{
+ struct hci_cp_le_set_scan_param param_cp;
+ struct hci_cp_le_set_scan_enable enable_cp;
+ struct hci_dev *hdev = req->hdev;
+ u8 own_addr_type;
+ u8 filter_policy;
+
+ /* Set require_privacy to false since no SCAN_REQ are send
+ * during passive scanning. Not using an non-resolvable address
+ * here is important so that peer devices using direct
+ * advertising with our address will be correctly reported
+ * by the controller.
+ */
+ if (hci_update_random_address(req, false, &own_addr_type))
+ return;
+
+ /* Adding or removing entries from the white list must
+ * happen before enabling scanning. The controller does
+ * not allow white list modification while scanning.
+ */
+ filter_policy = update_white_list(req);
+
+ /* When the controller is using random resolvable addresses and
+ * with that having LE privacy enabled, then controllers with
+ * Extended Scanner Filter Policies support can now enable support
+ * for handling directed advertising.
+ *
+ * So instead of using filter polices 0x00 (no whitelist)
+ * and 0x01 (whitelist enabled) use the new filter policies
+ * 0x02 (no whitelist) and 0x03 (whitelist enabled).
+ */
+ if (test_bit(HCI_PRIVACY, &hdev->dev_flags) &&
+ (hdev->le_features[0] & HCI_LE_EXT_SCAN_POLICY))
+ filter_policy |= 0x02;
+
+ memset(&param_cp, 0, sizeof(param_cp));
+ param_cp.type = LE_SCAN_PASSIVE;
+ param_cp.interval = cpu_to_le16(hdev->le_scan_interval);
+ param_cp.window = cpu_to_le16(hdev->le_scan_window);
+ param_cp.own_address_type = own_addr_type;
+ param_cp.filter_policy = filter_policy;
+ hci_req_add(req, HCI_OP_LE_SET_SCAN_PARAM, sizeof(param_cp),
+ &param_cp);
+
+ memset(&enable_cp, 0, sizeof(enable_cp));
+ enable_cp.enable = LE_SCAN_ENABLE;
+ enable_cp.filter_dup = LE_SCAN_FILTER_DUP_ENABLE;
+ hci_req_add(req, HCI_OP_LE_SET_SCAN_ENABLE, sizeof(enable_cp),
+ &enable_cp);
+}
+
+static void set_random_addr(struct hci_request *req, bdaddr_t *rpa)
+{
+ struct hci_dev *hdev = req->hdev;
+
+ /* If we're advertising or initiating an LE connection we can't
+ * go ahead and change the random address at this time. This is
+ * because the eventual initiator address used for the
+ * subsequently created connection will be undefined (some
+ * controllers use the new address and others the one we had
+ * when the operation started).
+ *
+ * In this kind of scenario skip the update and let the random
+ * address be updated at the next cycle.
+ */
+ if (test_bit(HCI_LE_ADV, &hdev->dev_flags) ||
+ hci_conn_hash_lookup_state(hdev, LE_LINK, BT_CONNECT)) {
+ BT_DBG("Deferring random address update");
+ set_bit(HCI_RPA_EXPIRED, &hdev->dev_flags);
+ return;
+ }
+
+ hci_req_add(req, HCI_OP_LE_SET_RANDOM_ADDR, 6, rpa);
+}
+
+int hci_update_random_address(struct hci_request *req, bool require_privacy,
+ u8 *own_addr_type)
+{
+ struct hci_dev *hdev = req->hdev;
+ int err;
+
+ /* If privacy is enabled use a resolvable private address. If
+ * current RPA has expired or there is something else than
+ * the current RPA in use, then generate a new one.
+ */
+ if (test_bit(HCI_PRIVACY, &hdev->dev_flags)) {
+ int to;
+
+ *own_addr_type = ADDR_LE_DEV_RANDOM;
+
+ if (!test_and_clear_bit(HCI_RPA_EXPIRED, &hdev->dev_flags) &&
+ !bacmp(&hdev->random_addr, &hdev->rpa))
+ return 0;
+
+ err = smp_generate_rpa(hdev, hdev->irk, &hdev->rpa);
+ if (err < 0) {
+ BT_ERR("%s failed to generate new RPA", hdev->name);
+ return err;
+ }
+
+ set_random_addr(req, &hdev->rpa);
+
+ to = msecs_to_jiffies(hdev->rpa_timeout * 1000);
+ queue_delayed_work(hdev->workqueue, &hdev->rpa_expired, to);
+
+ return 0;
+ }
+
+ /* In case of required privacy without resolvable private address,
+ * use an non-resolvable private address. This is useful for active
+ * scanning and non-connectable advertising.
+ */
+ if (require_privacy) {
+ bdaddr_t nrpa;
+
+ while (true) {
+ /* The non-resolvable private address is generated
+ * from random six bytes with the two most significant
+ * bits cleared.
+ */
+ get_random_bytes(&nrpa, 6);
+ nrpa.b[5] &= 0x3f;
+
+ /* The non-resolvable private address shall not be
+ * equal to the public address.
+ */
+ if (bacmp(&hdev->bdaddr, &nrpa))
+ break;
+ }
+
+ *own_addr_type = ADDR_LE_DEV_RANDOM;
+ set_random_addr(req, &nrpa);
+ return 0;
+ }
+
+ /* If forcing static address is in use or there is no public
+ * address use the static address as random address (but skip
+ * the HCI command if the current random address is already the
+ * static one.
+ *
+ * In case BR/EDR has been disabled on a dual-mode controller
+ * and a static address has been configured, then use that
+ * address instead of the public BR/EDR address.
+ */
+ if (test_bit(HCI_FORCE_STATIC_ADDR, &hdev->dbg_flags) ||
+ !bacmp(&hdev->bdaddr, BDADDR_ANY) ||
+ (!test_bit(HCI_BREDR_ENABLED, &hdev->dev_flags) &&
+ bacmp(&hdev->static_addr, BDADDR_ANY))) {
+ *own_addr_type = ADDR_LE_DEV_RANDOM;
+ if (bacmp(&hdev->static_addr, &hdev->random_addr))
+ hci_req_add(req, HCI_OP_LE_SET_RANDOM_ADDR, 6,
+ &hdev->static_addr);
+ return 0;
+ }
+
+ /* Neither privacy nor static address is being used so use a
+ * public address.
+ */
+ *own_addr_type = ADDR_LE_DEV_PUBLIC;
+
+ return 0;
+}
+
+static bool disconnected_whitelist_entries(struct hci_dev *hdev)
+{
+ struct bdaddr_list *b;
+
+ list_for_each_entry(b, &hdev->whitelist, list) {
+ struct hci_conn *conn;
+
+ conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &b->bdaddr);
+ if (!conn)
+ return true;
+
+ if (conn->state != BT_CONNECTED && conn->state != BT_CONFIG)
+ return true;
+ }
+
+ return false;
+}
+
+void __hci_update_page_scan(struct hci_request *req)
+{
+ struct hci_dev *hdev = req->hdev;
+ u8 scan;
+
+ if (!test_bit(HCI_BREDR_ENABLED, &hdev->dev_flags))
+ return;
+
+ if (!hdev_is_powered(hdev))
+ return;
+
+ if (mgmt_powering_down(hdev))
+ return;
+
+ if (test_bit(HCI_CONNECTABLE, &hdev->dev_flags) ||
+ disconnected_whitelist_entries(hdev))
+ scan = SCAN_PAGE;
+ else
+ scan = SCAN_DISABLED;
+
+ if (test_bit(HCI_PSCAN, &hdev->flags) == !!(scan & SCAN_PAGE))
+ return;
+
+ if (test_bit(HCI_DISCOVERABLE, &hdev->dev_flags))
+ scan |= SCAN_INQUIRY;
+
+ hci_req_add(req, HCI_OP_WRITE_SCAN_ENABLE, 1, &scan);
+}
+
+void hci_update_page_scan(struct hci_dev *hdev)
+{
+ struct hci_request req;
+
+ hci_req_init(&req, hdev);
+ __hci_update_page_scan(&req);
+ hci_req_run(&req, NULL);
+}
+
+/* This function controls the background scanning based on hdev->pend_le_conns
+ * list. If there are pending LE connection we start the background scanning,
+ * otherwise we stop it.
+ *
+ * This function requires the caller holds hdev->lock.
+ */
+void __hci_update_background_scan(struct hci_request *req)
+{
+ struct hci_dev *hdev = req->hdev;
+ struct hci_conn *conn;
+
+ if (!test_bit(HCI_UP, &hdev->flags) ||
+ test_bit(HCI_INIT, &hdev->flags) ||
+ test_bit(HCI_SETUP, &hdev->dev_flags) ||
+ test_bit(HCI_CONFIG, &hdev->dev_flags) ||
+ test_bit(HCI_AUTO_OFF, &hdev->dev_flags) ||
+ test_bit(HCI_UNREGISTER, &hdev->dev_flags))
+ return;
+
+ /* No point in doing scanning if LE support hasn't been enabled */
+ if (!test_bit(HCI_LE_ENABLED, &hdev->dev_flags))
+ return;
+
+ /* If discovery is active don't interfere with it */
+ if (hdev->discovery.state != DISCOVERY_STOPPED)
+ return;
+
+ /* Reset RSSI and UUID filters when starting background scanning
+ * since these filters are meant for service discovery only.
+ *
+ * The Start Discovery and Start Service Discovery operations
+ * ensure to set proper values for RSSI threshold and UUID
+ * filter list. So it is safe to just reset them here.
+ */
+ hci_discovery_filter_clear(hdev);
+
+ if (list_empty(&hdev->pend_le_conns) &&
+ list_empty(&hdev->pend_le_reports)) {
+ /* If there is no pending LE connections or devices
+ * to be scanned for, we should stop the background
+ * scanning.
+ */
+
+ /* If controller is not scanning we are done. */
+ if (!test_bit(HCI_LE_SCAN, &hdev->dev_flags))
+ return;
+
+ hci_req_add_le_scan_disable(req);
+
+ BT_DBG("%s stopping background scanning", hdev->name);
+ } else {
+ /* If there is at least one pending LE connection, we should
+ * keep the background scan running.
+ */
+
+ /* If controller is connecting, we should not start scanning
+ * since some controllers are not able to scan and connect at
+ * the same time.
+ */
+ conn = hci_conn_hash_lookup_state(hdev, LE_LINK, BT_CONNECT);
+ if (conn)
+ return;
+
+ /* If controller is currently scanning, we stop it to ensure we
+ * don't miss any advertising (due to duplicates filter).
+ */
+ if (test_bit(HCI_LE_SCAN, &hdev->dev_flags))
+ hci_req_add_le_scan_disable(req);
+
+ hci_req_add_le_passive_scan(req);
+
+ BT_DBG("%s starting background scanning", hdev->name);
+ }
+}
+
+static void update_background_scan_complete(struct hci_dev *hdev, u8 status,
+ u16 opcode)
+{
+ if (status)
+ BT_DBG("HCI request failed to update background scanning: "
+ "status 0x%2.2x", status);
+}
+
+void hci_update_background_scan(struct hci_dev *hdev)
+{
+ int err;
+ struct hci_request req;
+
+ hci_req_init(&req, hdev);
+
+ __hci_update_background_scan(&req);
+
+ err = hci_req_run(&req, update_background_scan_complete);
+ if (err && err != -ENODATA)
+ BT_ERR("Failed to run HCI request: err %d", err);
+}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.