mac802154: Handle basic beaconing

Implement the core hooks in order to provide the softMAC layer support
for sending beacons. Coordinators may be requested to send beacons in a
beacon enabled PAN in order for the other devices around to self
discover the available PANs automatically.

Changing the channels is prohibited while a beacon operation is
ongoing.

The implementation uses a workqueue triggered at a certain interval
depending on the symbol duration for the current channel and the
interval order provided.

Sending beacons in response to a BEACON_REQ frame (ie. answering active
scans) is not yet supported.

This initial patchset has no security support (llsec).

Co-developed-by: David Girault <david.girault@qorvo.com>
Signed-off-by: David Girault <david.girault@qorvo.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Alexander Aring <aahringo@redhat.com>
Link: https://lore.kernel.org/r/20230125102923.135465-3-miquel.raynal@bootlin.com
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
This commit is contained in:
Miquel Raynal 2023-01-25 11:29:23 +01:00 committed by Stefan Schmidt
parent 9bc114504b
commit 3accf47627
8 changed files with 246 additions and 3 deletions

View File

@ -129,6 +129,13 @@ enum ieee802154_frame_version {
IEEE802154_MULTIPURPOSE_STD = IEEE802154_2003_STD,
};
enum ieee802154_addressing_mode {
IEEE802154_NO_ADDRESSING,
IEEE802154_RESERVED,
IEEE802154_SHORT_ADDRESSING,
IEEE802154_EXTENDED_ADDRESSING,
};
struct ieee802154_hdr {
struct ieee802154_hdr_fc fc;
u8 seq;
@ -137,6 +144,11 @@ struct ieee802154_hdr {
struct ieee802154_sechdr sec;
};
struct ieee802154_beacon_frame {
struct ieee802154_hdr mhr;
struct ieee802154_beacon_hdr mac_pl;
};
/* pushes hdr onto the skb. fields of hdr->fc that can be calculated from
* the contents of hdr will be, and the actual value of those bits in
* hdr->fc will be ignored. this includes the INTRA_PAN bit and the frame
@ -162,6 +174,10 @@ int ieee802154_hdr_peek_addrs(const struct sk_buff *skb,
*/
int ieee802154_hdr_peek(const struct sk_buff *skb, struct ieee802154_hdr *hdr);
/* pushes a beacon frame into an skb */
int ieee802154_beacon_push(struct sk_buff *skb,
struct ieee802154_beacon_frame *beacon);
int ieee802154_max_payload(const struct ieee802154_hdr *hdr);
static inline int

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@ -120,6 +120,30 @@ ieee802154_hdr_push(struct sk_buff *skb, struct ieee802154_hdr *hdr)
}
EXPORT_SYMBOL_GPL(ieee802154_hdr_push);
int ieee802154_beacon_push(struct sk_buff *skb,
struct ieee802154_beacon_frame *beacon)
{
struct ieee802154_beacon_hdr *mac_pl = &beacon->mac_pl;
struct ieee802154_hdr *mhr = &beacon->mhr;
int ret;
skb_reserve(skb, sizeof(*mhr));
ret = ieee802154_hdr_push(skb, mhr);
if (ret < 0)
return ret;
skb_reset_mac_header(skb);
skb->mac_len = ret;
skb_put_data(skb, mac_pl, sizeof(*mac_pl));
if (mac_pl->pend_short_addr_count || mac_pl->pend_ext_addr_count)
return -EOPNOTSUPP;
return 0;
}
EXPORT_SYMBOL_GPL(ieee802154_beacon_push);
static int
ieee802154_hdr_get_addr(const u8 *buf, int mode, bool omit_pan,
struct ieee802154_addr *addr)

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@ -114,8 +114,8 @@ ieee802154_set_channel(struct wpan_phy *wpan_phy, u8 page, u8 channel)
wpan_phy->current_channel == channel)
return 0;
/* Refuse to change channels during a scanning operation */
if (mac802154_is_scanning(local))
/* Refuse to change channels during scanning or beaconing */
if (mac802154_is_scanning(local) || mac802154_is_beaconing(local))
return -EBUSY;
ret = drv_set_channel(local, page, channel);
@ -290,6 +290,31 @@ static int mac802154_abort_scan(struct wpan_phy *wpan_phy,
return mac802154_abort_scan_locked(local, sdata);
}
static int mac802154_send_beacons(struct wpan_phy *wpan_phy,
struct cfg802154_beacon_request *request)
{
struct ieee802154_sub_if_data *sdata;
sdata = IEEE802154_WPAN_DEV_TO_SUB_IF(request->wpan_dev);
ASSERT_RTNL();
return mac802154_send_beacons_locked(sdata, request);
}
static int mac802154_stop_beacons(struct wpan_phy *wpan_phy,
struct wpan_dev *wpan_dev)
{
struct ieee802154_local *local = wpan_phy_priv(wpan_phy);
struct ieee802154_sub_if_data *sdata;
sdata = IEEE802154_WPAN_DEV_TO_SUB_IF(wpan_dev);
ASSERT_RTNL();
return mac802154_stop_beacons_locked(local, sdata);
}
#ifdef CONFIG_IEEE802154_NL802154_EXPERIMENTAL
static void
ieee802154_get_llsec_table(struct wpan_phy *wpan_phy,
@ -499,6 +524,8 @@ const struct cfg802154_ops mac802154_config_ops = {
.set_ackreq_default = ieee802154_set_ackreq_default,
.trigger_scan = mac802154_trigger_scan,
.abort_scan = mac802154_abort_scan,
.send_beacons = mac802154_send_beacons,
.stop_beacons = mac802154_stop_beacons,
#ifdef CONFIG_IEEE802154_NL802154_EXPERIMENTAL
.get_llsec_table = ieee802154_get_llsec_table,
.lock_llsec_table = ieee802154_lock_llsec_table,

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@ -23,6 +23,7 @@
enum ieee802154_ongoing {
IEEE802154_IS_SCANNING = BIT(0),
IEEE802154_IS_BEACONING = BIT(1),
};
/* mac802154 device private data */
@ -60,6 +61,12 @@ struct ieee802154_local {
struct cfg802154_scan_request __rcu *scan_req;
struct delayed_work scan_work;
/* Beaconing */
unsigned int beacon_interval;
struct ieee802154_beacon_frame beacon;
struct cfg802154_beacon_request __rcu *beacon_req;
struct delayed_work beacon_work;
/* Asynchronous tasks */
struct list_head rx_beacon_list;
struct work_struct rx_beacon_work;
@ -257,6 +264,17 @@ static inline bool mac802154_is_scanning(struct ieee802154_local *local)
return test_bit(IEEE802154_IS_SCANNING, &local->ongoing);
}
void mac802154_beacon_worker(struct work_struct *work);
int mac802154_send_beacons_locked(struct ieee802154_sub_if_data *sdata,
struct cfg802154_beacon_request *request);
int mac802154_stop_beacons_locked(struct ieee802154_local *local,
struct ieee802154_sub_if_data *sdata);
static inline bool mac802154_is_beaconing(struct ieee802154_local *local)
{
return test_bit(IEEE802154_IS_BEACONING, &local->ongoing);
}
/* interface handling */
int ieee802154_iface_init(void);
void ieee802154_iface_exit(void);

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@ -305,6 +305,9 @@ static int mac802154_slave_close(struct net_device *dev)
if (mac802154_is_scanning(local))
mac802154_abort_scan_locked(local, sdata);
if (mac802154_is_beaconing(local))
mac802154_stop_beacons_locked(local, sdata);
netif_stop_queue(dev);
local->open_count--;

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@ -707,7 +707,10 @@ int mac802154_llsec_encrypt(struct mac802154_llsec *sec, struct sk_buff *skb)
hlen = ieee802154_hdr_pull(skb, &hdr);
if (hlen < 0 || hdr.fc.type != IEEE802154_FC_TYPE_DATA)
/* TODO: control frames security support */
if (hlen < 0 ||
(hdr.fc.type != IEEE802154_FC_TYPE_DATA &&
hdr.fc.type != IEEE802154_FC_TYPE_BEACON))
return -EINVAL;
if (!hdr.fc.security_enabled ||

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@ -99,6 +99,7 @@ ieee802154_alloc_hw(size_t priv_data_len, const struct ieee802154_ops *ops)
INIT_WORK(&local->sync_tx_work, ieee802154_xmit_sync_worker);
INIT_DELAYED_WORK(&local->scan_work, mac802154_scan_worker);
INIT_WORK(&local->rx_beacon_work, mac802154_rx_beacon_worker);
INIT_DELAYED_WORK(&local->beacon_work, mac802154_beacon_worker);
/* init supported flags with 802.15.4 default ranges */
phy->supported.max_minbe = 8;

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@ -16,6 +16,11 @@
#include "driver-ops.h"
#include "../ieee802154/nl802154.h"
#define IEEE802154_BEACON_MHR_SZ 13
#define IEEE802154_BEACON_PL_SZ 4
#define IEEE802154_BEACON_SKB_SZ (IEEE802154_BEACON_MHR_SZ + \
IEEE802154_BEACON_PL_SZ)
/* mac802154_scan_cleanup_locked() must be called upon scan completion or abort.
* - Completions are asynchronous, not locked by the rtnl and decided by the
* scan worker.
@ -286,3 +291,149 @@ int mac802154_process_beacon(struct ieee802154_local *local,
return 0;
}
static int mac802154_transmit_beacon(struct ieee802154_local *local,
struct wpan_dev *wpan_dev)
{
struct cfg802154_beacon_request *beacon_req;
struct ieee802154_sub_if_data *sdata;
struct sk_buff *skb;
int ret;
/* Update the sequence number */
local->beacon.mhr.seq = atomic_inc_return(&wpan_dev->bsn) & 0xFF;
skb = alloc_skb(IEEE802154_BEACON_SKB_SZ, GFP_KERNEL);
if (!skb)
return -ENOBUFS;
rcu_read_lock();
beacon_req = rcu_dereference(local->beacon_req);
if (unlikely(!beacon_req)) {
rcu_read_unlock();
kfree_skb(skb);
return -EINVAL;
}
sdata = IEEE802154_WPAN_DEV_TO_SUB_IF(beacon_req->wpan_dev);
skb->dev = sdata->dev;
rcu_read_unlock();
ret = ieee802154_beacon_push(skb, &local->beacon);
if (ret) {
kfree_skb(skb);
return ret;
}
return ieee802154_subif_start_xmit(skb, sdata->dev);
}
void mac802154_beacon_worker(struct work_struct *work)
{
struct ieee802154_local *local =
container_of(work, struct ieee802154_local, beacon_work.work);
struct cfg802154_beacon_request *beacon_req;
struct ieee802154_sub_if_data *sdata;
struct wpan_dev *wpan_dev;
int ret;
rcu_read_lock();
beacon_req = rcu_dereference(local->beacon_req);
if (unlikely(!beacon_req)) {
rcu_read_unlock();
return;
}
sdata = IEEE802154_WPAN_DEV_TO_SUB_IF(beacon_req->wpan_dev);
/* Wait an arbitrary amount of time in case we cannot use the device */
if (local->suspended || !ieee802154_sdata_running(sdata)) {
rcu_read_unlock();
queue_delayed_work(local->mac_wq, &local->beacon_work,
msecs_to_jiffies(1000));
return;
}
wpan_dev = beacon_req->wpan_dev;
rcu_read_unlock();
dev_dbg(&sdata->dev->dev, "Sending beacon\n");
ret = mac802154_transmit_beacon(local, wpan_dev);
if (ret)
dev_err(&sdata->dev->dev,
"Beacon could not be transmitted (%d)\n", ret);
if (local->beacon_interval >= 0)
queue_delayed_work(local->mac_wq, &local->beacon_work,
local->beacon_interval);
}
int mac802154_stop_beacons_locked(struct ieee802154_local *local,
struct ieee802154_sub_if_data *sdata)
{
struct wpan_dev *wpan_dev = &sdata->wpan_dev;
struct cfg802154_beacon_request *request;
ASSERT_RTNL();
if (!mac802154_is_beaconing(local))
return -ESRCH;
clear_bit(IEEE802154_IS_BEACONING, &local->ongoing);
cancel_delayed_work(&local->beacon_work);
request = rcu_replace_pointer(local->beacon_req, NULL, 1);
if (!request)
return 0;
kfree_rcu(request);
nl802154_beaconing_done(wpan_dev);
return 0;
}
int mac802154_send_beacons_locked(struct ieee802154_sub_if_data *sdata,
struct cfg802154_beacon_request *request)
{
struct ieee802154_local *local = sdata->local;
ASSERT_RTNL();
if (mac802154_is_beaconing(local))
mac802154_stop_beacons_locked(local, sdata);
/* Store beaconing parameters */
rcu_assign_pointer(local->beacon_req, request);
set_bit(IEEE802154_IS_BEACONING, &local->ongoing);
memset(&local->beacon, 0, sizeof(local->beacon));
local->beacon.mhr.fc.type = IEEE802154_FC_TYPE_BEACON;
local->beacon.mhr.fc.security_enabled = 0;
local->beacon.mhr.fc.frame_pending = 0;
local->beacon.mhr.fc.ack_request = 0;
local->beacon.mhr.fc.intra_pan = 0;
local->beacon.mhr.fc.dest_addr_mode = IEEE802154_NO_ADDRESSING;
local->beacon.mhr.fc.version = IEEE802154_2003_STD;
local->beacon.mhr.fc.source_addr_mode = IEEE802154_EXTENDED_ADDRESSING;
atomic_set(&request->wpan_dev->bsn, -1);
local->beacon.mhr.source.mode = IEEE802154_ADDR_LONG;
local->beacon.mhr.source.pan_id = cpu_to_le16(request->wpan_dev->pan_id);
local->beacon.mhr.source.extended_addr = cpu_to_le64(request->wpan_dev->extended_addr);
local->beacon.mac_pl.beacon_order = request->interval;
local->beacon.mac_pl.superframe_order = request->interval;
local->beacon.mac_pl.final_cap_slot = 0xf;
local->beacon.mac_pl.battery_life_ext = 0;
/* TODO: Fill this field depending on the coordinator capacity */
local->beacon.mac_pl.pan_coordinator = 1;
local->beacon.mac_pl.assoc_permit = 1;
/* Start the beacon work */
local->beacon_interval =
mac802154_scan_get_channel_time(request->interval,
request->wpan_phy->symbol_duration);
queue_delayed_work(local->mac_wq, &local->beacon_work, 0);
return 0;
}