swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: f76349cf41451c5c42a99f18a9163377e4b364ff authored by Linus Torvalds on 25 September 2022, 21:01:02 UTC
Linux 6.0-rc7
Linux 6.0-rc7
Tip revision: f76349c
msft.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2020 Google Corporation
*/
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/mgmt.h>
#include "hci_request.h"
#include "mgmt_util.h"
#include "msft.h"
#define MSFT_RSSI_THRESHOLD_VALUE_MIN -127
#define MSFT_RSSI_THRESHOLD_VALUE_MAX 20
#define MSFT_RSSI_LOW_TIMEOUT_MAX 0x3C
#define MSFT_OP_READ_SUPPORTED_FEATURES 0x00
struct msft_cp_read_supported_features {
__u8 sub_opcode;
} __packed;
struct msft_rp_read_supported_features {
__u8 status;
__u8 sub_opcode;
__le64 features;
__u8 evt_prefix_len;
__u8 evt_prefix[];
} __packed;
#define MSFT_OP_LE_MONITOR_ADVERTISEMENT 0x03
#define MSFT_MONITOR_ADVERTISEMENT_TYPE_PATTERN 0x01
struct msft_le_monitor_advertisement_pattern {
__u8 length;
__u8 data_type;
__u8 start_byte;
__u8 pattern[];
};
struct msft_le_monitor_advertisement_pattern_data {
__u8 count;
__u8 data[];
};
struct msft_cp_le_monitor_advertisement {
__u8 sub_opcode;
__s8 rssi_high;
__s8 rssi_low;
__u8 rssi_low_interval;
__u8 rssi_sampling_period;
__u8 cond_type;
__u8 data[];
} __packed;
struct msft_rp_le_monitor_advertisement {
__u8 status;
__u8 sub_opcode;
__u8 handle;
} __packed;
#define MSFT_OP_LE_CANCEL_MONITOR_ADVERTISEMENT 0x04
struct msft_cp_le_cancel_monitor_advertisement {
__u8 sub_opcode;
__u8 handle;
} __packed;
struct msft_rp_le_cancel_monitor_advertisement {
__u8 status;
__u8 sub_opcode;
} __packed;
#define MSFT_OP_LE_SET_ADVERTISEMENT_FILTER_ENABLE 0x05
struct msft_cp_le_set_advertisement_filter_enable {
__u8 sub_opcode;
__u8 enable;
} __packed;
struct msft_rp_le_set_advertisement_filter_enable {
__u8 status;
__u8 sub_opcode;
} __packed;
#define MSFT_EV_LE_MONITOR_DEVICE 0x02
struct msft_ev_le_monitor_device {
__u8 addr_type;
bdaddr_t bdaddr;
__u8 monitor_handle;
__u8 monitor_state;
} __packed;
struct msft_monitor_advertisement_handle_data {
__u8 msft_handle;
__u16 mgmt_handle;
struct list_head list;
};
struct msft_data {
__u64 features;
__u8 evt_prefix_len;
__u8 *evt_prefix;
struct list_head handle_map;
__u8 resuming;
__u8 suspending;
__u8 filter_enabled;
};
bool msft_monitor_supported(struct hci_dev *hdev)
{
return !!(msft_get_features(hdev) & MSFT_FEATURE_MASK_LE_ADV_MONITOR);
}
static bool read_supported_features(struct hci_dev *hdev,
struct msft_data *msft)
{
struct msft_cp_read_supported_features cp;
struct msft_rp_read_supported_features *rp;
struct sk_buff *skb;
cp.sub_opcode = MSFT_OP_READ_SUPPORTED_FEATURES;
skb = __hci_cmd_sync(hdev, hdev->msft_opcode, sizeof(cp), &cp,
HCI_CMD_TIMEOUT);
if (IS_ERR_OR_NULL(skb)) {
if (!skb)
skb = ERR_PTR(-EIO);
bt_dev_err(hdev, "Failed to read MSFT supported features (%ld)",
PTR_ERR(skb));
return false;
}
if (skb->len < sizeof(*rp)) {
bt_dev_err(hdev, "MSFT supported features length mismatch");
goto failed;
}
rp = (struct msft_rp_read_supported_features *)skb->data;
if (rp->sub_opcode != MSFT_OP_READ_SUPPORTED_FEATURES)
goto failed;
if (rp->evt_prefix_len > 0) {
msft->evt_prefix = kmemdup(rp->evt_prefix, rp->evt_prefix_len,
GFP_KERNEL);
if (!msft->evt_prefix)
goto failed;
}
msft->evt_prefix_len = rp->evt_prefix_len;
msft->features = __le64_to_cpu(rp->features);
if (msft->features & MSFT_FEATURE_MASK_CURVE_VALIDITY)
hdev->msft_curve_validity = true;
kfree_skb(skb);
return true;
failed:
kfree_skb(skb);
return false;
}
/* is_mgmt = true matches the handle exposed to userspace via mgmt.
* is_mgmt = false matches the handle used by the msft controller.
* This function requires the caller holds hdev->lock
*/
static struct msft_monitor_advertisement_handle_data *msft_find_handle_data
(struct hci_dev *hdev, u16 handle, bool is_mgmt)
{
struct msft_monitor_advertisement_handle_data *entry;
struct msft_data *msft = hdev->msft_data;
list_for_each_entry(entry, &msft->handle_map, list) {
if (is_mgmt && entry->mgmt_handle == handle)
return entry;
if (!is_mgmt && entry->msft_handle == handle)
return entry;
}
return NULL;
}
/* This function requires the caller holds hdev->lock */
static int msft_monitor_device_del(struct hci_dev *hdev, __u16 mgmt_handle,
bdaddr_t *bdaddr, __u8 addr_type,
bool notify)
{
struct monitored_device *dev, *tmp;
int count = 0;
list_for_each_entry_safe(dev, tmp, &hdev->monitored_devices, list) {
/* mgmt_handle == 0 indicates remove all devices, whereas,
* bdaddr == NULL indicates remove all devices matching the
* mgmt_handle.
*/
if ((!mgmt_handle || dev->handle == mgmt_handle) &&
(!bdaddr || (!bacmp(bdaddr, &dev->bdaddr) &&
addr_type == dev->addr_type))) {
if (notify && dev->notified) {
mgmt_adv_monitor_device_lost(hdev, dev->handle,
&dev->bdaddr,
dev->addr_type);
}
list_del(&dev->list);
kfree(dev);
count++;
}
}
return count;
}
static int msft_le_monitor_advertisement_cb(struct hci_dev *hdev, u16 opcode,
struct adv_monitor *monitor,
struct sk_buff *skb)
{
struct msft_rp_le_monitor_advertisement *rp;
struct msft_monitor_advertisement_handle_data *handle_data;
struct msft_data *msft = hdev->msft_data;
int status = 0;
hci_dev_lock(hdev);
rp = (struct msft_rp_le_monitor_advertisement *)skb->data;
if (skb->len < sizeof(*rp)) {
status = HCI_ERROR_UNSPECIFIED;
goto unlock;
}
status = rp->status;
if (status)
goto unlock;
handle_data = kmalloc(sizeof(*handle_data), GFP_KERNEL);
if (!handle_data) {
status = HCI_ERROR_UNSPECIFIED;
goto unlock;
}
handle_data->mgmt_handle = monitor->handle;
handle_data->msft_handle = rp->handle;
INIT_LIST_HEAD(&handle_data->list);
list_add(&handle_data->list, &msft->handle_map);
monitor->state = ADV_MONITOR_STATE_OFFLOADED;
unlock:
if (status)
hci_free_adv_monitor(hdev, monitor);
hci_dev_unlock(hdev);
return status;
}
static int msft_le_cancel_monitor_advertisement_cb(struct hci_dev *hdev,
u16 opcode,
struct adv_monitor *monitor,
struct sk_buff *skb)
{
struct msft_rp_le_cancel_monitor_advertisement *rp;
struct msft_monitor_advertisement_handle_data *handle_data;
struct msft_data *msft = hdev->msft_data;
int status = 0;
rp = (struct msft_rp_le_cancel_monitor_advertisement *)skb->data;
if (skb->len < sizeof(*rp)) {
status = HCI_ERROR_UNSPECIFIED;
goto done;
}
status = rp->status;
if (status)
goto done;
hci_dev_lock(hdev);
handle_data = msft_find_handle_data(hdev, monitor->handle, true);
if (handle_data) {
if (monitor->state == ADV_MONITOR_STATE_OFFLOADED)
monitor->state = ADV_MONITOR_STATE_REGISTERED;
/* Do not free the monitor if it is being removed due to
* suspend. It will be re-monitored on resume.
*/
if (!msft->suspending) {
hci_free_adv_monitor(hdev, monitor);
/* Clear any monitored devices by this Adv Monitor */
msft_monitor_device_del(hdev, handle_data->mgmt_handle,
NULL, 0, false);
}
list_del(&handle_data->list);
kfree(handle_data);
}
hci_dev_unlock(hdev);
done:
return status;
}
/* This function requires the caller holds hci_req_sync_lock */
static int msft_remove_monitor_sync(struct hci_dev *hdev,
struct adv_monitor *monitor)
{
struct msft_cp_le_cancel_monitor_advertisement cp;
struct msft_monitor_advertisement_handle_data *handle_data;
struct sk_buff *skb;
handle_data = msft_find_handle_data(hdev, monitor->handle, true);
/* If no matched handle, just remove without telling controller */
if (!handle_data)
return -ENOENT;
cp.sub_opcode = MSFT_OP_LE_CANCEL_MONITOR_ADVERTISEMENT;
cp.handle = handle_data->msft_handle;
skb = __hci_cmd_sync(hdev, hdev->msft_opcode, sizeof(cp), &cp,
HCI_CMD_TIMEOUT);
if (IS_ERR_OR_NULL(skb)) {
if (!skb)
return -EIO;
return PTR_ERR(skb);
}
return msft_le_cancel_monitor_advertisement_cb(hdev, hdev->msft_opcode,
monitor, skb);
}
/* This function requires the caller holds hci_req_sync_lock */
int msft_suspend_sync(struct hci_dev *hdev)
{
struct msft_data *msft = hdev->msft_data;
struct adv_monitor *monitor;
int handle = 0;
if (!msft || !msft_monitor_supported(hdev))
return 0;
msft->suspending = true;
while (1) {
monitor = idr_get_next(&hdev->adv_monitors_idr, &handle);
if (!monitor)
break;
msft_remove_monitor_sync(hdev, monitor);
handle++;
}
/* All monitors have been removed */
msft->suspending = false;
return 0;
}
static bool msft_monitor_rssi_valid(struct adv_monitor *monitor)
{
struct adv_rssi_thresholds *r = &monitor->rssi;
if (r->high_threshold < MSFT_RSSI_THRESHOLD_VALUE_MIN ||
r->high_threshold > MSFT_RSSI_THRESHOLD_VALUE_MAX ||
r->low_threshold < MSFT_RSSI_THRESHOLD_VALUE_MIN ||
r->low_threshold > MSFT_RSSI_THRESHOLD_VALUE_MAX)
return false;
/* High_threshold_timeout is not supported,
* once high_threshold is reached, events are immediately reported.
*/
if (r->high_threshold_timeout != 0)
return false;
if (r->low_threshold_timeout > MSFT_RSSI_LOW_TIMEOUT_MAX)
return false;
/* Sampling period from 0x00 to 0xFF are all allowed */
return true;
}
static bool msft_monitor_pattern_valid(struct adv_monitor *monitor)
{
return msft_monitor_rssi_valid(monitor);
/* No additional check needed for pattern-based monitor */
}
static int msft_add_monitor_sync(struct hci_dev *hdev,
struct adv_monitor *monitor)
{
struct msft_cp_le_monitor_advertisement *cp;
struct msft_le_monitor_advertisement_pattern_data *pattern_data;
struct msft_le_monitor_advertisement_pattern *pattern;
struct adv_pattern *entry;
size_t total_size = sizeof(*cp) + sizeof(*pattern_data);
ptrdiff_t offset = 0;
u8 pattern_count = 0;
struct sk_buff *skb;
if (!msft_monitor_pattern_valid(monitor))
return -EINVAL;
list_for_each_entry(entry, &monitor->patterns, list) {
pattern_count++;
total_size += sizeof(*pattern) + entry->length;
}
cp = kmalloc(total_size, GFP_KERNEL);
if (!cp)
return -ENOMEM;
cp->sub_opcode = MSFT_OP_LE_MONITOR_ADVERTISEMENT;
cp->rssi_high = monitor->rssi.high_threshold;
cp->rssi_low = monitor->rssi.low_threshold;
cp->rssi_low_interval = (u8)monitor->rssi.low_threshold_timeout;
cp->rssi_sampling_period = monitor->rssi.sampling_period;
cp->cond_type = MSFT_MONITOR_ADVERTISEMENT_TYPE_PATTERN;
pattern_data = (void *)cp->data;
pattern_data->count = pattern_count;
list_for_each_entry(entry, &monitor->patterns, list) {
pattern = (void *)(pattern_data->data + offset);
/* the length also includes data_type and offset */
pattern->length = entry->length + 2;
pattern->data_type = entry->ad_type;
pattern->start_byte = entry->offset;
memcpy(pattern->pattern, entry->value, entry->length);
offset += sizeof(*pattern) + entry->length;
}
skb = __hci_cmd_sync(hdev, hdev->msft_opcode, total_size, cp,
HCI_CMD_TIMEOUT);
kfree(cp);
if (IS_ERR_OR_NULL(skb)) {
if (!skb)
return -EIO;
return PTR_ERR(skb);
}
return msft_le_monitor_advertisement_cb(hdev, hdev->msft_opcode,
monitor, skb);
}
/* This function requires the caller holds hci_req_sync_lock */
static void reregister_monitor(struct hci_dev *hdev)
{
struct adv_monitor *monitor;
struct msft_data *msft = hdev->msft_data;
int handle = 0;
if (!msft)
return;
msft->resuming = true;
while (1) {
monitor = idr_get_next(&hdev->adv_monitors_idr, &handle);
if (!monitor)
break;
msft_add_monitor_sync(hdev, monitor);
handle++;
}
/* All monitors have been reregistered */
msft->resuming = false;
}
/* This function requires the caller holds hci_req_sync_lock */
int msft_resume_sync(struct hci_dev *hdev)
{
struct msft_data *msft = hdev->msft_data;
if (!msft || !msft_monitor_supported(hdev))
return 0;
hci_dev_lock(hdev);
/* Clear already tracked devices on resume. Once the monitors are
* reregistered, devices in range will be found again after resume.
*/
hdev->advmon_pend_notify = false;
msft_monitor_device_del(hdev, 0, NULL, 0, true);
hci_dev_unlock(hdev);
reregister_monitor(hdev);
return 0;
}
/* This function requires the caller holds hci_req_sync_lock */
void msft_do_open(struct hci_dev *hdev)
{
struct msft_data *msft = hdev->msft_data;
if (hdev->msft_opcode == HCI_OP_NOP)
return;
if (!msft) {
bt_dev_err(hdev, "MSFT extension not registered");
return;
}
bt_dev_dbg(hdev, "Initialize MSFT extension");
/* Reset existing MSFT data before re-reading */
kfree(msft->evt_prefix);
msft->evt_prefix = NULL;
msft->evt_prefix_len = 0;
msft->features = 0;
if (!read_supported_features(hdev, msft)) {
hdev->msft_data = NULL;
kfree(msft);
return;
}
if (msft_monitor_supported(hdev)) {
msft->resuming = true;
msft_set_filter_enable(hdev, true);
/* Monitors get removed on power off, so we need to explicitly
* tell the controller to re-monitor.
*/
reregister_monitor(hdev);
}
}
void msft_do_close(struct hci_dev *hdev)
{
struct msft_data *msft = hdev->msft_data;
struct msft_monitor_advertisement_handle_data *handle_data, *tmp;
struct adv_monitor *monitor;
if (!msft)
return;
bt_dev_dbg(hdev, "Cleanup of MSFT extension");
/* The controller will silently remove all monitors on power off.
* Therefore, remove handle_data mapping and reset monitor state.
*/
list_for_each_entry_safe(handle_data, tmp, &msft->handle_map, list) {
monitor = idr_find(&hdev->adv_monitors_idr,
handle_data->mgmt_handle);
if (monitor && monitor->state == ADV_MONITOR_STATE_OFFLOADED)
monitor->state = ADV_MONITOR_STATE_REGISTERED;
list_del(&handle_data->list);
kfree(handle_data);
}
hci_dev_lock(hdev);
/* Clear any devices that are being monitored and notify device lost */
hdev->advmon_pend_notify = false;
msft_monitor_device_del(hdev, 0, NULL, 0, true);
hci_dev_unlock(hdev);
}
void msft_register(struct hci_dev *hdev)
{
struct msft_data *msft = NULL;
bt_dev_dbg(hdev, "Register MSFT extension");
msft = kzalloc(sizeof(*msft), GFP_KERNEL);
if (!msft) {
bt_dev_err(hdev, "Failed to register MSFT extension");
return;
}
INIT_LIST_HEAD(&msft->handle_map);
hdev->msft_data = msft;
}
void msft_unregister(struct hci_dev *hdev)
{
struct msft_data *msft = hdev->msft_data;
if (!msft)
return;
bt_dev_dbg(hdev, "Unregister MSFT extension");
hdev->msft_data = NULL;
kfree(msft->evt_prefix);
kfree(msft);
}
/* This function requires the caller holds hdev->lock */
static void msft_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr,
__u8 addr_type, __u16 mgmt_handle)
{
struct monitored_device *dev;
dev = kmalloc(sizeof(*dev), GFP_KERNEL);
if (!dev) {
bt_dev_err(hdev, "MSFT vendor event %u: no memory",
MSFT_EV_LE_MONITOR_DEVICE);
return;
}
bacpy(&dev->bdaddr, bdaddr);
dev->addr_type = addr_type;
dev->handle = mgmt_handle;
dev->notified = false;
INIT_LIST_HEAD(&dev->list);
list_add(&dev->list, &hdev->monitored_devices);
hdev->advmon_pend_notify = true;
}
/* This function requires the caller holds hdev->lock */
static void msft_device_lost(struct hci_dev *hdev, bdaddr_t *bdaddr,
__u8 addr_type, __u16 mgmt_handle)
{
if (!msft_monitor_device_del(hdev, mgmt_handle, bdaddr, addr_type,
true)) {
bt_dev_err(hdev, "MSFT vendor event %u: dev %pMR not in list",
MSFT_EV_LE_MONITOR_DEVICE, bdaddr);
}
}
static void *msft_skb_pull(struct hci_dev *hdev, struct sk_buff *skb,
u8 ev, size_t len)
{
void *data;
data = skb_pull_data(skb, len);
if (!data)
bt_dev_err(hdev, "Malformed MSFT vendor event: 0x%02x", ev);
return data;
}
/* This function requires the caller holds hdev->lock */
static void msft_monitor_device_evt(struct hci_dev *hdev, struct sk_buff *skb)
{
struct msft_ev_le_monitor_device *ev;
struct msft_monitor_advertisement_handle_data *handle_data;
u8 addr_type;
ev = msft_skb_pull(hdev, skb, MSFT_EV_LE_MONITOR_DEVICE, sizeof(*ev));
if (!ev)
return;
bt_dev_dbg(hdev,
"MSFT vendor event 0x%02x: handle 0x%04x state %d addr %pMR",
MSFT_EV_LE_MONITOR_DEVICE, ev->monitor_handle,
ev->monitor_state, &ev->bdaddr);
handle_data = msft_find_handle_data(hdev, ev->monitor_handle, false);
if (!handle_data)
return;
switch (ev->addr_type) {
case ADDR_LE_DEV_PUBLIC:
addr_type = BDADDR_LE_PUBLIC;
break;
case ADDR_LE_DEV_RANDOM:
addr_type = BDADDR_LE_RANDOM;
break;
default:
bt_dev_err(hdev,
"MSFT vendor event 0x%02x: unknown addr type 0x%02x",
MSFT_EV_LE_MONITOR_DEVICE, ev->addr_type);
return;
}
if (ev->monitor_state)
msft_device_found(hdev, &ev->bdaddr, addr_type,
handle_data->mgmt_handle);
else
msft_device_lost(hdev, &ev->bdaddr, addr_type,
handle_data->mgmt_handle);
}
void msft_vendor_evt(struct hci_dev *hdev, void *data, struct sk_buff *skb)
{
struct msft_data *msft = hdev->msft_data;
u8 *evt_prefix;
u8 *evt;
if (!msft)
return;
/* When the extension has defined an event prefix, check that it
* matches, and otherwise just return.
*/
if (msft->evt_prefix_len > 0) {
evt_prefix = msft_skb_pull(hdev, skb, 0, msft->evt_prefix_len);
if (!evt_prefix)
return;
if (memcmp(evt_prefix, msft->evt_prefix, msft->evt_prefix_len))
return;
}
/* Every event starts at least with an event code and the rest of
* the data is variable and depends on the event code.
*/
if (skb->len < 1)
return;
evt = msft_skb_pull(hdev, skb, 0, sizeof(*evt));
if (!evt)
return;
hci_dev_lock(hdev);
switch (*evt) {
case MSFT_EV_LE_MONITOR_DEVICE:
msft_monitor_device_evt(hdev, skb);
break;
default:
bt_dev_dbg(hdev, "MSFT vendor event 0x%02x", *evt);
break;
}
hci_dev_unlock(hdev);
}
__u64 msft_get_features(struct hci_dev *hdev)
{
struct msft_data *msft = hdev->msft_data;
return msft ? msft->features : 0;
}
static void msft_le_set_advertisement_filter_enable_cb(struct hci_dev *hdev,
u8 status, u16 opcode,
struct sk_buff *skb)
{
struct msft_cp_le_set_advertisement_filter_enable *cp;
struct msft_rp_le_set_advertisement_filter_enable *rp;
struct msft_data *msft = hdev->msft_data;
rp = (struct msft_rp_le_set_advertisement_filter_enable *)skb->data;
if (skb->len < sizeof(*rp))
return;
/* Error 0x0C would be returned if the filter enabled status is
* already set to whatever we were trying to set.
* Although the default state should be disabled, some controller set
* the initial value to enabled. Because there is no way to know the
* actual initial value before sending this command, here we also treat
* error 0x0C as success.
*/
if (status != 0x00 && status != 0x0C)
return;
hci_dev_lock(hdev);
cp = hci_sent_cmd_data(hdev, hdev->msft_opcode);
msft->filter_enabled = cp->enable;
if (status == 0x0C)
bt_dev_warn(hdev, "MSFT filter_enable is already %s",
cp->enable ? "on" : "off");
hci_dev_unlock(hdev);
}
/* This function requires the caller holds hci_req_sync_lock */
int msft_add_monitor_pattern(struct hci_dev *hdev, struct adv_monitor *monitor)
{
struct msft_data *msft = hdev->msft_data;
if (!msft)
return -EOPNOTSUPP;
if (msft->resuming || msft->suspending)
return -EBUSY;
return msft_add_monitor_sync(hdev, monitor);
}
/* This function requires the caller holds hci_req_sync_lock */
int msft_remove_monitor(struct hci_dev *hdev, struct adv_monitor *monitor)
{
struct msft_data *msft = hdev->msft_data;
if (!msft)
return -EOPNOTSUPP;
if (msft->resuming || msft->suspending)
return -EBUSY;
return msft_remove_monitor_sync(hdev, monitor);
}
void msft_req_add_set_filter_enable(struct hci_request *req, bool enable)
{
struct hci_dev *hdev = req->hdev;
struct msft_cp_le_set_advertisement_filter_enable cp;
cp.sub_opcode = MSFT_OP_LE_SET_ADVERTISEMENT_FILTER_ENABLE;
cp.enable = enable;
hci_req_add(req, hdev->msft_opcode, sizeof(cp), &cp);
}
int msft_set_filter_enable(struct hci_dev *hdev, bool enable)
{
struct hci_request req;
struct msft_data *msft = hdev->msft_data;
int err;
if (!msft)
return -EOPNOTSUPP;
hci_req_init(&req, hdev);
msft_req_add_set_filter_enable(&req, enable);
err = hci_req_run_skb(&req, msft_le_set_advertisement_filter_enable_cb);
return err;
}
bool msft_curve_validity(struct hci_dev *hdev)
{
return hdev->msft_curve_validity;
}