diff options
Diffstat (limited to 'net/bluetooth/hci_request.c')
-rw-r--r-- | net/bluetooth/hci_request.c | 922 |
1 files changed, 922 insertions, 0 deletions
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c new file mode 100644 index 000000000..f7e006a36 --- /dev/null +++ b/net/bluetooth/hci_request.c @@ -0,0 +1,922 @@ +/* + 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 <linux/sched/signal.h> + +#include <net/bluetooth/bluetooth.h> +#include <net/bluetooth/hci_core.h> +#include <net/bluetooth/mgmt.h> + +#include "smp.h" +#include "hci_request.h" +#include "msft.h" +#include "eir.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; +} + +void hci_req_purge(struct hci_request *req) +{ + skb_queue_purge(&req->cmd_q); +} + +bool hci_req_status_pend(struct hci_dev *hdev) +{ + return hdev->req_status == HCI_REQ_PEND; +} + +static int req_run(struct hci_request *req, hci_req_complete_t complete, + hci_req_complete_skb_t complete_skb) +{ + struct hci_dev *hdev = req->hdev; + struct sk_buff *skb; + unsigned long flags; + + bt_dev_dbg(hdev, "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); + if (complete) { + bt_cb(skb)->hci.req_complete = complete; + } else if (complete_skb) { + bt_cb(skb)->hci.req_complete_skb = complete_skb; + bt_cb(skb)->hci.req_flags |= HCI_REQ_SKB; + } + + 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; +} + +int hci_req_run(struct hci_request *req, hci_req_complete_t complete) +{ + return req_run(req, complete, NULL); +} + +int hci_req_run_skb(struct hci_request *req, hci_req_complete_skb_t complete) +{ + return req_run(req, NULL, complete); +} + +void hci_req_sync_complete(struct hci_dev *hdev, u8 result, u16 opcode, + struct sk_buff *skb) +{ + bt_dev_dbg(hdev, "result 0x%2.2x", result); + + if (hdev->req_status == HCI_REQ_PEND) { + hdev->req_result = result; + hdev->req_status = HCI_REQ_DONE; + if (skb) + hdev->req_skb = skb_get(skb); + wake_up_interruptible(&hdev->req_wait_q); + } +} + +/* Execute request and wait for completion. */ +int __hci_req_sync(struct hci_dev *hdev, int (*func)(struct hci_request *req, + unsigned long opt), + unsigned long opt, u32 timeout, u8 *hci_status) +{ + struct hci_request req; + int err = 0; + + bt_dev_dbg(hdev, "start"); + + hci_req_init(&req, hdev); + + hdev->req_status = HCI_REQ_PEND; + + err = func(&req, opt); + if (err) { + if (hci_status) + *hci_status = HCI_ERROR_UNSPECIFIED; + return err; + } + + err = hci_req_run_skb(&req, hci_req_sync_complete); + if (err < 0) { + hdev->req_status = 0; + + /* ENODATA means the HCI request command queue is empty. + * This can happen when a request with conditionals doesn't + * trigger any commands to be sent. This is normal behavior + * and should not trigger an error return. + */ + if (err == -ENODATA) { + if (hci_status) + *hci_status = 0; + return 0; + } + + if (hci_status) + *hci_status = HCI_ERROR_UNSPECIFIED; + + return err; + } + + err = wait_event_interruptible_timeout(hdev->req_wait_q, + hdev->req_status != HCI_REQ_PEND, timeout); + + if (err == -ERESTARTSYS) + return -EINTR; + + switch (hdev->req_status) { + case HCI_REQ_DONE: + err = -bt_to_errno(hdev->req_result); + if (hci_status) + *hci_status = hdev->req_result; + break; + + case HCI_REQ_CANCELED: + err = -hdev->req_result; + if (hci_status) + *hci_status = HCI_ERROR_UNSPECIFIED; + break; + + default: + err = -ETIMEDOUT; + if (hci_status) + *hci_status = HCI_ERROR_UNSPECIFIED; + break; + } + + kfree_skb(hdev->req_skb); + hdev->req_skb = NULL; + hdev->req_status = hdev->req_result = 0; + + bt_dev_dbg(hdev, "end: err %d", err); + + return err; +} + +int hci_req_sync(struct hci_dev *hdev, int (*req)(struct hci_request *req, + unsigned long opt), + unsigned long opt, u32 timeout, u8 *hci_status) +{ + int ret; + + /* Serialize all requests */ + hci_req_sync_lock(hdev); + /* check the state after obtaing the lock to protect the HCI_UP + * against any races from hci_dev_do_close when the controller + * gets removed. + */ + if (test_bit(HCI_UP, &hdev->flags)) + ret = __hci_req_sync(hdev, req, opt, timeout, hci_status); + else + ret = -ENETDOWN; + hci_req_sync_unlock(hdev); + + return ret; +} + +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 = skb_put(skb, HCI_COMMAND_HDR_SIZE); + hdr->opcode = cpu_to_le16(opcode); + hdr->plen = plen; + + if (plen) + skb_put_data(skb, param, plen); + + bt_dev_dbg(hdev, "skb len %d", skb->len); + + hci_skb_pkt_type(skb) = HCI_COMMAND_PKT; + hci_skb_opcode(skb) = 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_dev_dbg(hdev, "opcode 0x%4.4x plen %d", 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_dev_err(hdev, "no memory for command (opcode 0x%4.4x)", + opcode); + req->err = -ENOMEM; + return; + } + + if (skb_queue_empty(&req->cmd_q)) + bt_cb(skb)->hci.req_flags |= HCI_REQ_START; + + hci_skb_event(skb) = event; + + skb_queue_tail(&req->cmd_q, skb); +} + +void hci_req_add(struct hci_request *req, u16 opcode, u32 plen, + const void *param) +{ + bt_dev_dbg(req->hdev, "HCI_REQ-0x%4.4x", opcode); + hci_req_add_ev(req, opcode, plen, param, 0); +} + +static void start_interleave_scan(struct hci_dev *hdev) +{ + hdev->interleave_scan_state = INTERLEAVE_SCAN_NO_FILTER; + queue_delayed_work(hdev->req_workqueue, + &hdev->interleave_scan, 0); +} + +static bool is_interleave_scanning(struct hci_dev *hdev) +{ + return hdev->interleave_scan_state != INTERLEAVE_SCAN_NONE; +} + +static void cancel_interleave_scan(struct hci_dev *hdev) +{ + bt_dev_dbg(hdev, "cancelling interleave scan"); + + cancel_delayed_work_sync(&hdev->interleave_scan); + + hdev->interleave_scan_state = INTERLEAVE_SCAN_NONE; +} + +/* Return true if interleave_scan wasn't started until exiting this function, + * otherwise, return false + */ +static bool __hci_update_interleaved_scan(struct hci_dev *hdev) +{ + /* Do interleaved scan only if all of the following are true: + * - There is at least one ADV monitor + * - At least one pending LE connection or one device to be scanned for + * - Monitor offloading is not supported + * If so, we should alternate between allowlist scan and one without + * any filters to save power. + */ + bool use_interleaving = hci_is_adv_monitoring(hdev) && + !(list_empty(&hdev->pend_le_conns) && + list_empty(&hdev->pend_le_reports)) && + hci_get_adv_monitor_offload_ext(hdev) == + HCI_ADV_MONITOR_EXT_NONE; + bool is_interleaving = is_interleave_scanning(hdev); + + if (use_interleaving && !is_interleaving) { + start_interleave_scan(hdev); + bt_dev_dbg(hdev, "starting interleave scan"); + return true; + } + + if (!use_interleaving && is_interleaving) + cancel_interleave_scan(hdev); + + return false; +} + +void hci_req_add_le_scan_disable(struct hci_request *req, bool rpa_le_conn) +{ + struct hci_dev *hdev = req->hdev; + + if (hdev->scanning_paused) { + bt_dev_dbg(hdev, "Scanning is paused for suspend"); + return; + } + + if (use_ext_scan(hdev)) { + struct hci_cp_le_set_ext_scan_enable cp; + + memset(&cp, 0, sizeof(cp)); + cp.enable = LE_SCAN_DISABLE; + hci_req_add(req, HCI_OP_LE_SET_EXT_SCAN_ENABLE, sizeof(cp), + &cp); + } else { + 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); + } + + /* Disable address resolution */ + if (hci_dev_test_flag(hdev, HCI_LL_RPA_RESOLUTION) && !rpa_le_conn) { + __u8 enable = 0x00; + + hci_req_add(req, HCI_OP_LE_SET_ADDR_RESOLV_ENABLE, 1, &enable); + } +} + +static void del_from_accept_list(struct hci_request *req, bdaddr_t *bdaddr, + u8 bdaddr_type) +{ + struct hci_cp_le_del_from_accept_list cp; + + cp.bdaddr_type = bdaddr_type; + bacpy(&cp.bdaddr, bdaddr); + + bt_dev_dbg(req->hdev, "Remove %pMR (0x%x) from accept list", &cp.bdaddr, + cp.bdaddr_type); + hci_req_add(req, HCI_OP_LE_DEL_FROM_ACCEPT_LIST, sizeof(cp), &cp); + + if (use_ll_privacy(req->hdev)) { + struct smp_irk *irk; + + irk = hci_find_irk_by_addr(req->hdev, bdaddr, bdaddr_type); + if (irk) { + struct hci_cp_le_del_from_resolv_list cp; + + cp.bdaddr_type = bdaddr_type; + bacpy(&cp.bdaddr, bdaddr); + + hci_req_add(req, HCI_OP_LE_DEL_FROM_RESOLV_LIST, + sizeof(cp), &cp); + } + } +} + +/* Adds connection to accept list if needed. On error, returns -1. */ +static int add_to_accept_list(struct hci_request *req, + struct hci_conn_params *params, u8 *num_entries, + bool allow_rpa) +{ + struct hci_cp_le_add_to_accept_list cp; + struct hci_dev *hdev = req->hdev; + + /* Already in accept list */ + if (hci_bdaddr_list_lookup(&hdev->le_accept_list, ¶ms->addr, + params->addr_type)) + return 0; + + /* Select filter policy to accept all advertising */ + if (*num_entries >= hdev->le_accept_list_size) + return -1; + + /* Accept list can not be used with RPAs */ + if (!allow_rpa && + !hci_dev_test_flag(hdev, HCI_ENABLE_LL_PRIVACY) && + hci_find_irk_by_addr(hdev, ¶ms->addr, params->addr_type)) { + return -1; + } + + /* During suspend, only wakeable devices can be in accept list */ + if (hdev->suspended && + !(params->flags & HCI_CONN_FLAG_REMOTE_WAKEUP)) + return 0; + + *num_entries += 1; + cp.bdaddr_type = params->addr_type; + bacpy(&cp.bdaddr, ¶ms->addr); + + bt_dev_dbg(hdev, "Add %pMR (0x%x) to accept list", &cp.bdaddr, + cp.bdaddr_type); + hci_req_add(req, HCI_OP_LE_ADD_TO_ACCEPT_LIST, sizeof(cp), &cp); + + if (use_ll_privacy(hdev)) { + struct smp_irk *irk; + + irk = hci_find_irk_by_addr(hdev, ¶ms->addr, + params->addr_type); + if (irk) { + struct hci_cp_le_add_to_resolv_list cp; + + cp.bdaddr_type = params->addr_type; + bacpy(&cp.bdaddr, ¶ms->addr); + memcpy(cp.peer_irk, irk->val, 16); + + if (hci_dev_test_flag(hdev, HCI_PRIVACY)) + memcpy(cp.local_irk, hdev->irk, 16); + else + memset(cp.local_irk, 0, 16); + + hci_req_add(req, HCI_OP_LE_ADD_TO_RESOLV_LIST, + sizeof(cp), &cp); + } + } + + return 0; +} + +static u8 update_accept_list(struct hci_request *req) +{ + struct hci_dev *hdev = req->hdev; + struct hci_conn_params *params; + struct bdaddr_list *b; + u8 num_entries = 0; + bool pend_conn, pend_report; + /* We allow usage of accept list even with RPAs in suspend. In the worst + * case, we won't be able to wake from devices that use the privacy1.2 + * features. Additionally, once we support privacy1.2 and IRK + * offloading, we can update this to also check for those conditions. + */ + bool allow_rpa = hdev->suspended; + + if (use_ll_privacy(hdev)) + allow_rpa = true; + + /* Go through the current accept 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_accept_list, list) { + pend_conn = hci_pend_le_action_lookup(&hdev->pend_le_conns, + &b->bdaddr, + b->bdaddr_type); + pend_report = hci_pend_le_action_lookup(&hdev->pend_le_reports, + &b->bdaddr, + b->bdaddr_type); + + /* If the device is not likely to connect or report, + * remove it from the accept list. + */ + if (!pend_conn && !pend_report) { + del_from_accept_list(req, &b->bdaddr, b->bdaddr_type); + continue; + } + + /* Accept list can not be used with RPAs */ + if (!allow_rpa && + !hci_dev_test_flag(hdev, HCI_ENABLE_LL_PRIVACY) && + hci_find_irk_by_addr(hdev, &b->bdaddr, b->bdaddr_type)) { + return 0x00; + } + + num_entries++; + } + + /* Since all no longer valid accept 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 accept list entries in the controller, then + * just abort and return filer policy value to not use the + * accept list. + */ + list_for_each_entry(params, &hdev->pend_le_conns, action) { + if (add_to_accept_list(req, params, &num_entries, allow_rpa)) + return 0x00; + } + + /* After adding all new pending connections, walk through + * the list of pending reports and also add these to the + * accept list if there is still space. Abort if space runs out. + */ + list_for_each_entry(params, &hdev->pend_le_reports, action) { + if (add_to_accept_list(req, params, &num_entries, allow_rpa)) + return 0x00; + } + + /* Use the allowlist unless the following conditions are all true: + * - We are not currently suspending + * - There are 1 or more ADV monitors registered and it's not offloaded + * - Interleaved scanning is not currently using the allowlist + */ + if (!idr_is_empty(&hdev->adv_monitors_idr) && !hdev->suspended && + hci_get_adv_monitor_offload_ext(hdev) == HCI_ADV_MONITOR_EXT_NONE && + hdev->interleave_scan_state != INTERLEAVE_SCAN_ALLOWLIST) + return 0x00; + + /* Select filter policy to use accept list */ + return 0x01; +} + +static bool scan_use_rpa(struct hci_dev *hdev) +{ + return hci_dev_test_flag(hdev, HCI_PRIVACY); +} + +static void hci_req_start_scan(struct hci_request *req, u8 type, u16 interval, + u16 window, u8 own_addr_type, u8 filter_policy, + bool filter_dup, bool addr_resolv) +{ + struct hci_dev *hdev = req->hdev; + + if (hdev->scanning_paused) { + bt_dev_dbg(hdev, "Scanning is paused for suspend"); + return; + } + + if (use_ll_privacy(hdev) && addr_resolv) { + u8 enable = 0x01; + + hci_req_add(req, HCI_OP_LE_SET_ADDR_RESOLV_ENABLE, 1, &enable); + } + + /* Use ext scanning if set ext scan param and ext scan enable is + * supported + */ + if (use_ext_scan(hdev)) { + struct hci_cp_le_set_ext_scan_params *ext_param_cp; + struct hci_cp_le_set_ext_scan_enable ext_enable_cp; + struct hci_cp_le_scan_phy_params *phy_params; + u8 data[sizeof(*ext_param_cp) + sizeof(*phy_params) * 2]; + u32 plen; + + ext_param_cp = (void *)data; + phy_params = (void *)ext_param_cp->data; + + memset(ext_param_cp, 0, sizeof(*ext_param_cp)); + ext_param_cp->own_addr_type = own_addr_type; + ext_param_cp->filter_policy = filter_policy; + + plen = sizeof(*ext_param_cp); + + if (scan_1m(hdev) || scan_2m(hdev)) { + ext_param_cp->scanning_phys |= LE_SCAN_PHY_1M; + + memset(phy_params, 0, sizeof(*phy_params)); + phy_params->type = type; + phy_params->interval = cpu_to_le16(interval); + phy_params->window = cpu_to_le16(window); + + plen += sizeof(*phy_params); + phy_params++; + } + + if (scan_coded(hdev)) { + ext_param_cp->scanning_phys |= LE_SCAN_PHY_CODED; + + memset(phy_params, 0, sizeof(*phy_params)); + phy_params->type = type; + phy_params->interval = cpu_to_le16(interval); + phy_params->window = cpu_to_le16(window); + + plen += sizeof(*phy_params); + phy_params++; + } + + hci_req_add(req, HCI_OP_LE_SET_EXT_SCAN_PARAMS, + plen, ext_param_cp); + + memset(&ext_enable_cp, 0, sizeof(ext_enable_cp)); + ext_enable_cp.enable = LE_SCAN_ENABLE; + ext_enable_cp.filter_dup = filter_dup; + + hci_req_add(req, HCI_OP_LE_SET_EXT_SCAN_ENABLE, + sizeof(ext_enable_cp), &ext_enable_cp); + } else { + struct hci_cp_le_set_scan_param param_cp; + struct hci_cp_le_set_scan_enable enable_cp; + + memset(¶m_cp, 0, sizeof(param_cp)); + param_cp.type = type; + param_cp.interval = cpu_to_le16(interval); + param_cp.window = cpu_to_le16(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), + ¶m_cp); + + memset(&enable_cp, 0, sizeof(enable_cp)); + enable_cp.enable = LE_SCAN_ENABLE; + enable_cp.filter_dup = filter_dup; + hci_req_add(req, HCI_OP_LE_SET_SCAN_ENABLE, sizeof(enable_cp), + &enable_cp); + } +} + +/* Returns true if an le connection is in the scanning state */ +static inline bool hci_is_le_conn_scanning(struct hci_dev *hdev) +{ + struct hci_conn_hash *h = &hdev->conn_hash; + struct hci_conn *c; + + rcu_read_lock(); + + list_for_each_entry_rcu(c, &h->list, list) { + if (c->type == LE_LINK && c->state == BT_CONNECT && + test_bit(HCI_CONN_SCANNING, &c->flags)) { + rcu_read_unlock(); + return true; + } + } + + rcu_read_unlock(); + + return false; +} + +static void set_random_addr(struct hci_request *req, bdaddr_t *rpa); +static int hci_update_random_address(struct hci_request *req, + bool require_privacy, bool use_rpa, + 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 (use_rpa) { + /* If Controller supports LL Privacy use own address type is + * 0x03 + */ + if (use_ll_privacy(hdev)) + *own_addr_type = ADDR_LE_DEV_RANDOM_RESOLVED; + else + *own_addr_type = ADDR_LE_DEV_RANDOM; + + if (rpa_valid(hdev)) + return 0; + + err = smp_generate_rpa(hdev, hdev->irk, &hdev->rpa); + if (err < 0) { + bt_dev_err(hdev, "failed to generate new RPA"); + return err; + } + + set_random_addr(req, &hdev->rpa); + + 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 (hci_dev_test_flag(hdev, HCI_FORCE_STATIC_ADDR) || + !bacmp(&hdev->bdaddr, BDADDR_ANY) || + (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED) && + 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; +} + +/* Ensure to call hci_req_add_le_scan_disable() first to disable the + * controller based address resolution to be able to reconfigure + * resolving list. + */ +void hci_req_add_le_passive_scan(struct hci_request *req) +{ + struct hci_dev *hdev = req->hdev; + u8 own_addr_type; + u8 filter_policy; + u16 window, interval; + /* Default is to enable duplicates filter */ + u8 filter_dup = LE_SCAN_FILTER_DUP_ENABLE; + /* Background scanning should run with address resolution */ + bool addr_resolv = true; + + if (hdev->scanning_paused) { + bt_dev_dbg(hdev, "Scanning is paused for suspend"); + return; + } + + /* 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, scan_use_rpa(hdev), + &own_addr_type)) + return; + + if (hdev->enable_advmon_interleave_scan && + __hci_update_interleaved_scan(hdev)) + return; + + bt_dev_dbg(hdev, "interleave state %d", hdev->interleave_scan_state); + /* Adding or removing entries from the accept list must + * happen before enabling scanning. The controller does + * not allow accept list modification while scanning. + */ + filter_policy = update_accept_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 accept list) + * and 0x01 (accept list enabled) use the new filter policies + * 0x02 (no accept list) and 0x03 (accept list enabled). + */ + if (hci_dev_test_flag(hdev, HCI_PRIVACY) && + (hdev->le_features[0] & HCI_LE_EXT_SCAN_POLICY)) + filter_policy |= 0x02; + + if (hdev->suspended) { + window = hdev->le_scan_window_suspend; + interval = hdev->le_scan_int_suspend; + } else if (hci_is_le_conn_scanning(hdev)) { + window = hdev->le_scan_window_connect; + interval = hdev->le_scan_int_connect; + } else if (hci_is_adv_monitoring(hdev)) { + window = hdev->le_scan_window_adv_monitor; + interval = hdev->le_scan_int_adv_monitor; + + /* Disable duplicates filter when scanning for advertisement + * monitor for the following reasons. + * + * For HW pattern filtering (ex. MSFT), Realtek and Qualcomm + * controllers ignore RSSI_Sampling_Period when the duplicates + * filter is enabled. + * + * For SW pattern filtering, when we're not doing interleaved + * scanning, it is necessary to disable duplicates filter, + * otherwise hosts can only receive one advertisement and it's + * impossible to know if a peer is still in range. + */ + filter_dup = LE_SCAN_FILTER_DUP_DISABLE; + } else { + window = hdev->le_scan_window; + interval = hdev->le_scan_interval; + } + + bt_dev_dbg(hdev, "LE passive scan with accept list = %d", + filter_policy); + hci_req_start_scan(req, LE_SCAN_PASSIVE, interval, window, + own_addr_type, filter_policy, filter_dup, + addr_resolv); +} + +static int hci_req_add_le_interleaved_scan(struct hci_request *req, + unsigned long opt) +{ + struct hci_dev *hdev = req->hdev; + int ret = 0; + + hci_dev_lock(hdev); + + if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) + hci_req_add_le_scan_disable(req, false); + hci_req_add_le_passive_scan(req); + + switch (hdev->interleave_scan_state) { + case INTERLEAVE_SCAN_ALLOWLIST: + bt_dev_dbg(hdev, "next state: allowlist"); + hdev->interleave_scan_state = INTERLEAVE_SCAN_NO_FILTER; + break; + case INTERLEAVE_SCAN_NO_FILTER: + bt_dev_dbg(hdev, "next state: no filter"); + hdev->interleave_scan_state = INTERLEAVE_SCAN_ALLOWLIST; + break; + case INTERLEAVE_SCAN_NONE: + BT_ERR("unexpected error"); + ret = -1; + } + + hci_dev_unlock(hdev); + + return ret; +} + +static void interleave_scan_work(struct work_struct *work) +{ + struct hci_dev *hdev = container_of(work, struct hci_dev, + interleave_scan.work); + u8 status; + unsigned long timeout; + + if (hdev->interleave_scan_state == INTERLEAVE_SCAN_ALLOWLIST) { + timeout = msecs_to_jiffies(hdev->advmon_allowlist_duration); + } else if (hdev->interleave_scan_state == INTERLEAVE_SCAN_NO_FILTER) { + timeout = msecs_to_jiffies(hdev->advmon_no_filter_duration); + } else { + bt_dev_err(hdev, "unexpected error"); + return; + } + + hci_req_sync(hdev, hci_req_add_le_interleaved_scan, 0, + HCI_CMD_TIMEOUT, &status); + + /* Don't continue interleaving if it was canceled */ + if (is_interleave_scanning(hdev)) + queue_delayed_work(hdev->req_workqueue, + &hdev->interleave_scan, timeout); +} + +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 (hci_dev_test_flag(hdev, HCI_LE_ADV) || + hci_lookup_le_connect(hdev)) { + bt_dev_dbg(hdev, "Deferring random address update"); + hci_dev_set_flag(hdev, HCI_RPA_EXPIRED); + return; + } + + hci_req_add(req, HCI_OP_LE_SET_RANDOM_ADDR, 6, rpa); +} + +void hci_request_setup(struct hci_dev *hdev) +{ + INIT_DELAYED_WORK(&hdev->interleave_scan, interleave_scan_work); +} + +void hci_request_cancel_all(struct hci_dev *hdev) +{ + __hci_cmd_sync_cancel(hdev, ENODEV); + + cancel_interleave_scan(hdev); +} |