2013-08-02 15:38:17

by Simon Wunderlich

[permalink] [raw]
Subject: [PATCH 0/7] add IBSS channel switch announcement support

This patchset adds channel switch support for IBSS mode. This is required for
later DFS support in IBSS. It builds on top of the previously submitted AP DFS
patchset.

The rough design is:
* Userspace may request to change channel using the already introduced
NL80211_CMD_CHANNEL_SWITCH command. Unlike AP mode, it does not contain
IEs or offset for CSA elements, because this is to be generated by the kernel.
* Also other stations may request a channel change by sending (E)CSA within
beacons or action frames. This is parsed and further handled as if it would
have come from userspace.
* When performing a channel switch, an action frame is sent, because beaconing
is distributed among IBSS peers and might be lost early. Furthermore,
channel switch announcement IEs are added to the beacon/probe response.
* When a channel switch could was not understood, it disconnects from the
IBSS and tries to re-connect.

Discussion points:
* When disconnecting from the IBSS because a channel switch announcement was
bogus or not understood, we might reconnect to the same BSS again - on the
old channel, because the other stas are still there, and stay there.
Although it is "accepted behaviour" in IEEE 802.11 that not all station
could make it, we should consider ignoring beacons/presp if they include CSAs
when scanning for networks to prevent this problem.

As always, any comments are appreciated.

Cheers,
Simon

Simon Wunderlich (7):
cfg80211: export cfg80211_chandef_dfs_required
mac80211: fix ieee80211_sta_process_chanswitch for 5/10 MHz channels
mac80211: split off channel switch parsing function
mac80211: move ibss presp generation in own function
mac80211: add support for CSA in IBSS mode
mac80211: send a CSA action frame when changing channel
nl80211: enable IBSS support for channel switch announcements

include/net/cfg80211.h | 9 +
net/mac80211/cfg.c | 84 ++++--
net/mac80211/ibss.c | 715 +++++++++++++++++++++++++++++++++++---------
net/mac80211/ieee80211_i.h | 24 ++
net/mac80211/iface.c | 4 +
net/mac80211/mlme.c | 143 +++++----
net/mac80211/rx.c | 36 ++-
net/mac80211/tx.c | 34 ++-
net/wireless/chan.c | 1 +
net/wireless/core.h | 8 -
net/wireless/nl80211.c | 49 ++-
11 files changed, 853 insertions(+), 254 deletions(-)

--
1.7.10.4



2013-08-02 15:38:18

by Simon Wunderlich

[permalink] [raw]
Subject: [PATCH 4/7] mac80211: move ibss presp generation in own function

Channel Switch will later require to generate beacons without setting
them immediately. Therefore split the presp generation in an own
function. Splitting the original very long function might be a good idea
anyway.

Signed-off-by: Simon Wunderlich <[email protected]>
Signed-off-by: Mathias Kretschmer <[email protected]>
---
net/mac80211/ibss.c | 185 ++++++++++++++++++++++++++++++---------------------
1 file changed, 109 insertions(+), 76 deletions(-)

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index e08387c..29f1a7b 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -34,13 +34,12 @@

#define IEEE80211_IBSS_MAX_STA_ENTRIES 128

-
-static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
- const u8 *bssid, const int beacon_int,
- struct ieee80211_channel *chan,
- const u32 basic_rates,
- const u16 capability, u64 tsf,
- bool creator)
+static struct beacon_data *
+ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
+ const int beacon_int, const u32 basic_rates,
+ const u16 capability, u64 tsf,
+ struct cfg80211_chan_def *chandef,
+ bool *have_higher_than_11mbit)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
@@ -48,70 +47,11 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt;
u8 *pos;
struct ieee80211_supported_band *sband;
- struct cfg80211_bss *bss;
- u32 bss_change, rate_flags, rates = 0, rates_added = 0;
- struct cfg80211_chan_def chandef;
- enum nl80211_bss_scan_width scan_width;
- bool have_higher_than_11mbit = false;
+ u32 rate_flags, rates = 0, rates_added = 0;
struct beacon_data *presp;
int frame_len;
int shift;

- sdata_assert_lock(sdata);
-
- /* Reset own TSF to allow time synchronization work. */
- drv_reset_tsf(local, sdata);
-
- if (!ether_addr_equal(ifibss->bssid, bssid))
- sta_info_flush(sdata);
-
- /* if merging, indicate to driver that we leave the old IBSS */
- if (sdata->vif.bss_conf.ibss_joined) {
- sdata->vif.bss_conf.ibss_joined = false;
- sdata->vif.bss_conf.ibss_creator = false;
- sdata->vif.bss_conf.enable_beacon = false;
- netif_carrier_off(sdata->dev);
- ieee80211_bss_info_change_notify(sdata,
- BSS_CHANGED_IBSS |
- BSS_CHANGED_BEACON_ENABLED);
- }
-
- presp = rcu_dereference_protected(ifibss->presp,
- lockdep_is_held(&sdata->wdev.mtx));
- rcu_assign_pointer(ifibss->presp, NULL);
- if (presp)
- kfree_rcu(presp, rcu_head);
-
- sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
-
- chandef = ifibss->chandef;
- if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
- if (chandef.width == NL80211_CHAN_WIDTH_5 ||
- chandef.width == NL80211_CHAN_WIDTH_10 ||
- chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
- chandef.width == NL80211_CHAN_WIDTH_20) {
- sdata_info(sdata,
- "Failed to join IBSS, beacons forbidden\n");
- return;
- }
- chandef.width = NL80211_CHAN_WIDTH_20;
- chandef.center_freq1 = chan->center_freq;
- }
-
- ieee80211_vif_release_channel(sdata);
- if (ieee80211_vif_use_channel(sdata, &chandef,
- ifibss->fixed_channel ?
- IEEE80211_CHANCTX_SHARED :
- IEEE80211_CHANCTX_EXCLUSIVE)) {
- sdata_info(sdata, "Failed to join IBSS, no channel context\n");
- return;
- }
-
- memcpy(ifibss->bssid, bssid, ETH_ALEN);
-
- sband = local->hw.wiphy->bands[chan->band];
- shift = ieee80211_vif_get_shift(&sdata->vif);
-
/* Build IBSS probe response */
frame_len = sizeof(struct ieee80211_hdr_3addr) +
12 /* struct ieee80211_mgmt.u.beacon */ +
@@ -125,7 +65,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
ifibss->ie_len;
presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
if (!presp)
- return;
+ return NULL;

presp->head = (void *)(presp + 1);

@@ -146,12 +86,19 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
memcpy(pos, ifibss->ssid, ifibss->ssid_len);
pos += ifibss->ssid_len;

- rate_flags = ieee80211_chandef_rate_flags(&chandef);
+ sband = local->hw.wiphy->bands[chandef->chan->band];
+ rate_flags = ieee80211_chandef_rate_flags(chandef);
+ shift = ieee80211_chandef_get_shift(chandef);
+ rates_n = 0;
+ if (have_higher_than_11mbit)
+ *have_higher_than_11mbit = false;
+
for (i = 0; i < sband->n_bitrates; i++) {
if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
continue;
- if (sband->bitrates[i].bitrate > 110)
- have_higher_than_11mbit = true;
+ if (sband->bitrates[i].bitrate > 110 &&
+ have_higher_than_11mbit)
+ *have_higher_than_11mbit = true;

rates |= BIT(i);
rates_n++;
@@ -178,7 +125,8 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
if (sband->band == IEEE80211_BAND_2GHZ) {
*pos++ = WLAN_EID_DS_PARAMS;
*pos++ = 1;
- *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
+ *pos++ = ieee80211_frequency_to_channel(
+ chandef->chan->center_freq);
}

*pos++ = WLAN_EID_IBSS_PARAMS;
@@ -210,9 +158,9 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
}

/* add HT capability and information IEs */
- if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
- chandef.width != NL80211_CHAN_WIDTH_5 &&
- chandef.width != NL80211_CHAN_WIDTH_10 &&
+ if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
+ chandef->width != NL80211_CHAN_WIDTH_5 &&
+ chandef->width != NL80211_CHAN_WIDTH_10 &&
sband->ht_cap.ht_supported) {
struct ieee80211_sta_ht_cap ht_cap;

@@ -226,7 +174,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
* keep them at 0
*/
pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
- &chandef, 0);
+ chandef, 0);
}

if (local->hw.queues >= IEEE80211_NUM_ACS) {
@@ -243,9 +191,94 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,

presp->head_len = pos - presp->head;
if (WARN_ON(presp->head_len > frame_len))
+ goto error;
+
+ return presp;
+error:
+ kfree(presp);
+ return NULL;
+}
+
+static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
+ const u8 *bssid, const int beacon_int,
+ struct ieee80211_channel *chan,
+ const u32 basic_rates,
+ const u16 capability, u64 tsf,
+ bool creator)
+{
+ struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+ struct ieee80211_local *local = sdata->local;
+ struct ieee80211_supported_band *sband;
+ struct ieee80211_mgmt *mgmt;
+ struct cfg80211_bss *bss;
+ u32 bss_change;
+ struct cfg80211_chan_def chandef;
+ struct beacon_data *presp;
+ enum nl80211_bss_scan_width scan_width;
+ bool have_higher_than_11mbit;
+
+ sdata_assert_lock(sdata);
+
+ /* Reset own TSF to allow time synchronization work. */
+ drv_reset_tsf(local, sdata);
+
+ if (!ether_addr_equal(ifibss->bssid, bssid))
+ sta_info_flush(sdata);
+
+ /* if merging, indicate to driver that we leave the old IBSS */
+ if (sdata->vif.bss_conf.ibss_joined) {
+ sdata->vif.bss_conf.ibss_joined = false;
+ sdata->vif.bss_conf.ibss_creator = false;
+ sdata->vif.bss_conf.enable_beacon = false;
+ netif_carrier_off(sdata->dev);
+ ieee80211_bss_info_change_notify(sdata,
+ BSS_CHANGED_IBSS |
+ BSS_CHANGED_BEACON_ENABLED);
+ }
+
+ presp = rcu_dereference_protected(ifibss->presp,
+ lockdep_is_held(&sdata->wdev.mtx));
+ rcu_assign_pointer(ifibss->presp, NULL);
+ if (presp)
+ kfree_rcu(presp, rcu_head);
+
+ sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
+
+ chandef = ifibss->chandef;
+ if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
+ if (chandef.width == NL80211_CHAN_WIDTH_5 ||
+ chandef.width == NL80211_CHAN_WIDTH_10 ||
+ chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
+ chandef.width == NL80211_CHAN_WIDTH_20) {
+ sdata_info(sdata,
+ "Failed to join IBSS, beacons forbidden\n");
+ return;
+ }
+ chandef.width = NL80211_CHAN_WIDTH_20;
+ chandef.center_freq1 = chan->center_freq;
+ }
+
+ ieee80211_vif_release_channel(sdata);
+ if (ieee80211_vif_use_channel(sdata, &chandef,
+ ifibss->fixed_channel ?
+ IEEE80211_CHANCTX_SHARED :
+ IEEE80211_CHANCTX_EXCLUSIVE)) {
+ sdata_info(sdata, "Failed to join IBSS, no channel context\n");
+ return;
+ }
+
+ memcpy(ifibss->bssid, bssid, ETH_ALEN);
+
+ sband = local->hw.wiphy->bands[chan->band];
+
+ presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
+ capability, tsf, &chandef,
+ &have_higher_than_11mbit);
+ if (!presp)
return;

rcu_assign_pointer(ifibss->presp, presp);
+ mgmt = (void *)presp->head;

sdata->vif.bss_conf.enable_beacon = true;
sdata->vif.bss_conf.beacon_int = beacon_int;
--
1.7.10.4


2013-08-02 15:38:20

by Simon Wunderlich

[permalink] [raw]
Subject: [PATCH 7/7] nl80211: enable IBSS support for channel switch announcements

Signed-off-by: Simon Wunderlich <[email protected]>
Signed-off-by: Mathias Kretschmer <[email protected]>
---
net/wireless/nl80211.c | 49 +++++++++++++++++++++++++++++++++---------------
1 file changed, 34 insertions(+), 15 deletions(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index f7cb121..6d3d788 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5632,15 +5632,26 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
static struct nlattr *csa_attrs[NL80211_ATTR_MAX+1];
u8 radar_detect_width = 0;
int err;
+ bool need_new_beacon = false;

if (!rdev->ops->channel_switch ||
!(rdev->wiphy.flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
return -EOPNOTSUPP;

- /* may add IBSS support later */
- if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP &&
- dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO)
+ switch (dev->ieee80211_ptr->iftype) {
+ case NL80211_IFTYPE_AP:
+ case NL80211_IFTYPE_P2P_GO:
+ need_new_beacon = true;
+
+ /* useless if AP is not running */
+ if (!wdev->beacon_interval)
+ return -EINVAL;
+ break;
+ case NL80211_IFTYPE_ADHOC:
+ break;
+ default:
return -EOPNOTSUPP;
+ }

memset(&params, 0, sizeof(params));

@@ -5649,15 +5660,16 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
return -EINVAL;

/* only important for AP, IBSS and mesh create IEs internally */
- if (!info->attrs[NL80211_ATTR_CSA_IES])
- return -EINVAL;
-
- /* useless if AP is not running */
- if (!wdev->beacon_interval)
+ if (need_new_beacon &&
+ (!info->attrs[NL80211_ATTR_CSA_IES] ||
+ !info->attrs[NL80211_ATTR_CSA_C_OFF_BEACON]))
return -EINVAL;

params.count = nla_get_u32(info->attrs[NL80211_ATTR_CH_SWITCH_COUNT]);

+ if (!need_new_beacon)
+ goto skip_beacons;
+
err = nl80211_parse_beacon(info->attrs, &params.beacon_after);
if (err)
return err;
@@ -5697,6 +5709,7 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
return -EINVAL;
}

+skip_beacons:
err = nl80211_parse_chandef(rdev, info, &params.chandef);
if (err)
return err;
@@ -5704,12 +5717,17 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
if (!cfg80211_reg_can_beacon(&rdev->wiphy, &params.chandef))
return -EINVAL;

- err = cfg80211_chandef_dfs_required(wdev->wiphy, &params.chandef);
- if (err < 0) {
- return err;
- } else if (err) {
- radar_detect_width = BIT(params.chandef.width);
- params.radar_required = true;
+ /* DFS channels are only supported for AP/P2P GO ... for now. */
+ if (dev->ieee80211_ptr->iftype == NL80211_IFTYPE_AP ||
+ dev->ieee80211_ptr->iftype == NL80211_IFTYPE_P2P_GO) {
+ err = cfg80211_chandef_dfs_required(wdev->wiphy,
+ &params.chandef);
+ if (err < 0) {
+ return err;
+ } else if (err) {
+ radar_detect_width = BIT(params.chandef.width);
+ params.radar_required = true;
+ }
}

err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
@@ -10725,7 +10743,8 @@ void cfg80211_ch_switch_notify(struct net_device *dev,
wdev_lock(wdev);

if (WARN_ON(wdev->iftype != NL80211_IFTYPE_AP &&
- wdev->iftype != NL80211_IFTYPE_P2P_GO))
+ wdev->iftype != NL80211_IFTYPE_P2P_GO &&
+ wdev->iftype != NL80211_IFTYPE_ADHOC))
goto out;

wdev->channel = chandef->chan;
--
1.7.10.4


2013-08-02 15:38:19

by Simon Wunderlich

[permalink] [raw]
Subject: [PATCH 3/7] mac80211: split off channel switch parsing function

The channel switch parsing function can be re-used for the IBSS code,
put the common part into an extra function.

Signed-off-by: Simon Wunderlich <[email protected]>
Signed-off-by: Mathias Kretschmer <[email protected]>
---
net/mac80211/ieee80211_i.h | 22 +++++++
net/mac80211/mlme.c | 136 ++++++++++++++++++++++++--------------------
2 files changed, 97 insertions(+), 61 deletions(-)

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index e94c840..1275bde 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1333,6 +1333,9 @@ int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata);
void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata);
void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb);
+int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
+ struct cfg80211_csa_settings *csa_settings);
+int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata);

/* mesh code */
void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata);
@@ -1560,6 +1563,25 @@ static inline void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata,
u32 ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action,
struct ieee802_11_elems *elems,
u64 filter, u32 crc);
+
+/**
+ * ieee80211_parse_ch_switch_ie - parses channel switch IEs
+ * @sdata: the sdata of the interface which has received the frame
+ * @elems: parsed 802.11 elements received with the frame
+ * @beacon: indicates if the frame was a beacon or probe response
+ * @current_band: indicates the current band
+ * @sta_flags: contains information about own capabilities and restrictions
+ * @count: to be filled with the counter until the switch (on success only)
+ * @mode: to be filled with CSA mode (on success only)
+ * @new_chandef: to be filled with destination chandef (on success only)
+ * Return: 0 on success, <0 on error and >0 if there is nothing to parse.
+ */
+int ieee80211_parse_ch_switch_ie(struct ieee80211_sub_if_data *sdata,
+ struct ieee802_11_elems *elems, bool beacon,
+ enum ieee80211_band current_band,
+ u32 sta_flags, u8 *count, u8 *mode,
+ struct cfg80211_chan_def *new_chandef);
+
static inline void ieee802_11_parse_elems(const u8 *start, size_t len,
bool action,
struct ieee802_11_elems *elems)
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 45a87ee..60554c8 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -981,54 +981,35 @@ static void ieee80211_chswitch_timer(unsigned long data)
ieee80211_queue_work(&sdata->local->hw, &sdata->u.mgd.chswitch_work);
}

-static void
-ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
- u64 timestamp, struct ieee802_11_elems *elems,
- bool beacon)
+int ieee80211_parse_ch_switch_ie(struct ieee80211_sub_if_data *sdata,
+ struct ieee802_11_elems *elems, bool beacon,
+ enum ieee80211_band current_band,
+ u32 sta_flags, u8 *count, u8 *mode,
+ struct cfg80211_chan_def *new_chandef)
{
- struct ieee80211_local *local = sdata->local;
- struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
- struct cfg80211_bss *cbss = ifmgd->associated;
- struct ieee80211_bss *bss;
- struct ieee80211_chanctx *chanctx;
enum ieee80211_band new_band;
int new_freq;
u8 new_chan_no;
- u8 count;
- u8 mode;
struct ieee80211_channel *new_chan;
- struct cfg80211_chan_def new_chandef = {};
struct cfg80211_chan_def new_vht_chandef = {};
const struct ieee80211_sec_chan_offs_ie *sec_chan_offs;
const struct ieee80211_wide_bw_chansw_ie *wide_bw_chansw_ie;
const struct ieee80211_ht_operation *ht_oper;
int secondary_channel_offset = -1;

- sdata_assert_lock(sdata);
-
- if (!cbss)
- return;
-
- if (local->scanning)
- return;
-
- /* disregard subsequent announcements if we are already processing */
- if (ifmgd->flags & IEEE80211_STA_CSA_RECEIVED)
- return;
-
sec_chan_offs = elems->sec_chan_offs;
wide_bw_chansw_ie = elems->wide_bw_chansw_ie;
ht_oper = elems->ht_operation;

- if (ifmgd->flags & (IEEE80211_STA_DISABLE_HT |
- IEEE80211_STA_DISABLE_40MHZ)) {
+ if (sta_flags & (IEEE80211_STA_DISABLE_HT |
+ IEEE80211_STA_DISABLE_40MHZ)) {
sec_chan_offs = NULL;
wide_bw_chansw_ie = NULL;
/* only used for bandwidth here */
ht_oper = NULL;
}

- if (ifmgd->flags & IEEE80211_STA_DISABLE_VHT)
+ if (sta_flags & IEEE80211_STA_DISABLE_VHT)
wide_bw_chansw_ie = NULL;

if (elems->ext_chansw_ie) {
@@ -1038,33 +1019,28 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
sdata_info(sdata,
"cannot understand ECSA IE operating class %d, disconnecting\n",
elems->ext_chansw_ie->new_operating_class);
- ieee80211_queue_work(&local->hw,
- &ifmgd->csa_connection_drop_work);
+ return -EINVAL;
}
new_chan_no = elems->ext_chansw_ie->new_ch_num;
- count = elems->ext_chansw_ie->count;
- mode = elems->ext_chansw_ie->mode;
+ *count = elems->ext_chansw_ie->count;
+ *mode = elems->ext_chansw_ie->mode;
} else if (elems->ch_switch_ie) {
- new_band = cbss->channel->band;
+ new_band = current_band;
new_chan_no = elems->ch_switch_ie->new_ch_num;
- count = elems->ch_switch_ie->count;
- mode = elems->ch_switch_ie->mode;
+ *count = elems->ch_switch_ie->count;
+ *mode = elems->ch_switch_ie->mode;
} else {
/* nothing here we understand */
- return;
+ return 1;
}

- bss = (void *)cbss->priv;
-
new_freq = ieee80211_channel_to_frequency(new_chan_no, new_band);
new_chan = ieee80211_get_channel(sdata->local->hw.wiphy, new_freq);
if (!new_chan || new_chan->flags & IEEE80211_CHAN_DISABLED) {
sdata_info(sdata,
- "AP %pM switches to unsupported channel (%d MHz), disconnecting\n",
- ifmgd->associated->bssid, new_freq);
- ieee80211_queue_work(&local->hw,
- &ifmgd->csa_connection_drop_work);
- return;
+ "network switches to unsupported channel (%d MHz), disconnecting\n",
+ new_freq);
+ return -EINVAL;
}

if (!beacon && sec_chan_offs) {
@@ -1072,7 +1048,7 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
} else if (beacon && ht_oper) {
secondary_channel_offset =
ht_oper->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET;
- } else if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT)) {
+ } else if (!(sta_flags & IEEE80211_STA_DISABLE_HT)) {
/*
* If it's not a beacon, HT is enabled and the IE not present,
* it's 20 MHz, 802.11-2012 8.5.2.6:
@@ -1088,25 +1064,25 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
default:
/* secondary_channel_offset was present but is invalid */
case IEEE80211_HT_PARAM_CHA_SEC_NONE:
- cfg80211_chandef_create(&new_chandef, new_chan,
+ cfg80211_chandef_create(new_chandef, new_chan,
NL80211_CHAN_HT20);
break;
case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
- cfg80211_chandef_create(&new_chandef, new_chan,
+ cfg80211_chandef_create(new_chandef, new_chan,
NL80211_CHAN_HT40PLUS);
break;
case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
- cfg80211_chandef_create(&new_chandef, new_chan,
+ cfg80211_chandef_create(new_chandef, new_chan,
NL80211_CHAN_HT40MINUS);
break;
case -1:
- cfg80211_chandef_create(&new_chandef, new_chan,
+ cfg80211_chandef_create(new_chandef, new_chan,
NL80211_CHAN_NO_HT);
/* keep width for 5/10 MHz channels */
switch (sdata->vif.bss_conf.chandef.width) {
case NL80211_CHAN_WIDTH_5:
case NL80211_CHAN_WIDTH_10:
- new_chandef.width = sdata->vif.bss_conf.chandef.width;
+ new_chandef->width = sdata->vif.bss_conf.chandef.width;
break;
default:
break;
@@ -1142,13 +1118,13 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
new_vht_chandef.width = NL80211_CHAN_WIDTH_80P80;
break;
}
- if (ifmgd->flags & IEEE80211_STA_DISABLE_80P80MHZ &&
+ if (sta_flags & IEEE80211_STA_DISABLE_80P80MHZ &&
new_vht_chandef.width == NL80211_CHAN_WIDTH_80P80)
chandef_downgrade(&new_vht_chandef);
- if (ifmgd->flags & IEEE80211_STA_DISABLE_160MHZ &&
+ if (sta_flags & IEEE80211_STA_DISABLE_160MHZ &&
new_vht_chandef.width == NL80211_CHAN_WIDTH_160)
chandef_downgrade(&new_vht_chandef);
- if (ifmgd->flags & IEEE80211_STA_DISABLE_40MHZ &&
+ if (sta_flags & IEEE80211_STA_DISABLE_40MHZ &&
new_vht_chandef.width > NL80211_CHAN_WIDTH_20)
chandef_downgrade(&new_vht_chandef);
}
@@ -1156,23 +1132,61 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
/* if VHT data is there validate & use it */
if (new_vht_chandef.chan) {
if (!cfg80211_chandef_compatible(&new_vht_chandef,
- &new_chandef)) {
+ new_chandef)) {
sdata_info(sdata,
- "AP %pM CSA has inconsistent channel data, disconnecting\n",
- ifmgd->associated->bssid);
- ieee80211_queue_work(&local->hw,
- &ifmgd->csa_connection_drop_work);
- return;
+ "network CSA has inconsistent channel data, disconnecting\n");
+ return -EINVAL;
}
- new_chandef = new_vht_chandef;
+ *new_chandef = new_vht_chandef;
}

+ return 0;
+}
+
+static void
+ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
+ u64 timestamp, struct ieee802_11_elems *elems,
+ bool beacon)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+ struct cfg80211_bss *cbss = ifmgd->associated;
+ struct ieee80211_chanctx *chanctx;
+ enum ieee80211_band current_band;
+ u8 count;
+ u8 mode;
+ struct cfg80211_chan_def new_chandef = {};
+ int res;
+
+ sdata_assert_lock(sdata);
+
+ if (!cbss)
+ return;
+
+ if (local->scanning)
+ return;
+
+ /* disregard subsequent announcements if we are already processing */
+ if (ifmgd->flags & IEEE80211_STA_CSA_RECEIVED)
+ return;
+
+ current_band = cbss->channel->band;
+ res = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, current_band,
+ ifmgd->flags, &count, &mode,
+ &new_chandef);
+ if (res < 0)
+ ieee80211_queue_work(&local->hw,
+ &ifmgd->csa_connection_drop_work);
+ if (res)
+ return;
+
if (!cfg80211_chandef_usable(local->hw.wiphy, &new_chandef,
IEEE80211_CHAN_DISABLED)) {
sdata_info(sdata,
- "AP %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
- ifmgd->associated->bssid, new_freq,
- new_chandef.width, new_chandef.center_freq1,
+ "network switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
+ new_chandef.chan->center_freq,
+ new_chandef.width,
+ new_chandef.center_freq1,
new_chandef.center_freq2);
ieee80211_queue_work(&local->hw,
&ifmgd->csa_connection_drop_work);
--
1.7.10.4


2013-08-02 15:38:17

by Simon Wunderlich

[permalink] [raw]
Subject: [PATCH 2/7] mac80211: fix ieee80211_sta_process_chanswitch for 5/10 MHz channels

Signed-off-by: Simon Wunderlich <[email protected]>
Signed-off-by: Mathias Kretschmer <[email protected]>
---
net/mac80211/mlme.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 211246b..45a87ee 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1102,6 +1102,15 @@ ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
case -1:
cfg80211_chandef_create(&new_chandef, new_chan,
NL80211_CHAN_NO_HT);
+ /* keep width for 5/10 MHz channels */
+ switch (sdata->vif.bss_conf.chandef.width) {
+ case NL80211_CHAN_WIDTH_5:
+ case NL80211_CHAN_WIDTH_10:
+ new_chandef.width = sdata->vif.bss_conf.chandef.width;
+ break;
+ default:
+ break;
+ }
break;
}

--
1.7.10.4


2013-08-02 15:38:20

by Simon Wunderlich

[permalink] [raw]
Subject: [PATCH 1/7] cfg80211: export cfg80211_chandef_dfs_required

It will be used later by the IBSS CSA implementation of mac80211.

Signed-off-by: Simon Wunderlich <[email protected]>
Signed-off-by: Mathias Kretschmer <[email protected]>
---
include/net/cfg80211.h | 9 +++++++++
net/wireless/chan.c | 1 +
net/wireless/core.h | 8 --------
3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 6da5a6b..14c914f 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -437,6 +437,15 @@ bool cfg80211_chandef_usable(struct wiphy *wiphy,
u32 prohibited_flags);

/**
+ * cfg80211_chandef_dfs_required - checks if radar detection is required
+ * @wiphy: the wiphy to validate against
+ * @chandef: the channel definition to check
+ * Return: 1 if radar detection is required, 0 if it is not, < 0 on error
+ */
+int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
+ const struct cfg80211_chan_def *c);
+
+/**
* ieee80211_chandef_rate_flags - returns rate flags for a channel
*
* In some channel types, not all rates may be used - for example CCK
diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index 50f6195..16f3c3a 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -328,6 +328,7 @@ int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
return cfg80211_get_chans_dfs_required(wiphy, chandef->center_freq2,
width);
}
+EXPORT_SYMBOL(cfg80211_chandef_dfs_required);

static bool cfg80211_secondary_chans_ok(struct wiphy *wiphy,
u32 center_freq, u32 bandwidth,
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 9ad43c6..8ed2094 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -382,14 +382,6 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,
enum cfg80211_chan_mode chanmode,
u8 radar_detect);

-/**
- * cfg80211_chandef_dfs_required - checks if radar detection is required
- * @wiphy: the wiphy to validate against
- * @chandef: the channel definition to check
- * Return: 1 if radar detection is required, 0 if it is not, < 0 on error
- */
-int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
- const struct cfg80211_chan_def *c);

void cfg80211_set_dfs_state(struct wiphy *wiphy,
const struct cfg80211_chan_def *chandef,
--
1.7.10.4


2013-08-02 15:38:21

by Simon Wunderlich

[permalink] [raw]
Subject: [PATCH 5/7] mac80211: add support for CSA in IBSS mode

Ths function adds the channel switch announcement implementation for the
IBSS code. It is triggered by userspace (mac80211/cfg) or by external
channel switch announcement, which have to be adopted. Both CSAs in
beacons and action frames are supported. As for AP mode, the channel
switch is applied after some time. However in IBSS mode, the channel
switch IEs are generated in the kernel.

Signed-off-by: Simon Wunderlich <[email protected]>
Signed-off-by: Mathias Kretschmer <[email protected]>
---
net/mac80211/cfg.c | 84 +++++---
net/mac80211/ibss.c | 475 ++++++++++++++++++++++++++++++++++++++------
net/mac80211/ieee80211_i.h | 2 +
net/mac80211/iface.c | 4 +
net/mac80211/rx.c | 36 +++-
net/mac80211/tx.c | 34 +++-
6 files changed, 537 insertions(+), 98 deletions(-)

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 44449ce..e603450 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -2852,30 +2852,35 @@ void ieee80211_csa_finalize_work(struct work_struct *work)
if (!ieee80211_sdata_running(sdata))
return;

- if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP))
- return;
-
sdata->radar_required = sdata->csa_radar_required;
err = ieee80211_vif_change_channel(sdata, &local->csa_chandef,
&changed);
if (WARN_ON(err < 0))
return;

- err = ieee80211_assign_beacon(sdata, sdata->u.ap.next_beacon);
- if (err < 0)
+ ieee80211_bss_info_change_notify(sdata, changed);
+
+ if (sdata->vif.type == NL80211_IFTYPE_AP) {
+ err = ieee80211_assign_beacon(sdata, sdata->u.ap.next_beacon);
+ if (err < 0)
+ return;
+ changed |= err;
+ kfree(sdata->u.ap.next_beacon);
+ sdata->u.ap.next_beacon = NULL;
+
+ ieee80211_bss_info_change_notify(sdata, err);
+ } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
+ ieee80211_ibss_finish_csa(sdata);
+ } else {
+ WARN_ON(1);
return;
-
- changed |= err;
- kfree(sdata->u.ap.next_beacon);
- sdata->u.ap.next_beacon = NULL;
+ }
sdata->vif.csa_active = false;

ieee80211_wake_queues_by_reason(&sdata->local->hw,
IEEE80211_MAX_QUEUE_MAP,
IEEE80211_QUEUE_STOP_REASON_CSA);

- ieee80211_bss_info_change_notify(sdata, changed);
-
cfg80211_ch_switch_notify(sdata->dev, &local->csa_chandef);
}

@@ -2923,20 +2928,56 @@ static int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
if (sdata->vif.csa_active)
return -EBUSY;

- /* only handle AP for now. */
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP:
+ sdata->csa_counter_offset_beacon =
+ params->counter_offset_beacon;
+ sdata->csa_counter_offset_presp = params->counter_offset_presp;
+ sdata->u.ap.next_beacon =
+ cfg80211_beacon_dup(&params->beacon_after);
+ if (!sdata->u.ap.next_beacon)
+ return -ENOMEM;
+
+ err = ieee80211_assign_beacon(sdata, &params->beacon_csa);
+ if (err < 0) {
+ kfree(sdata->u.ap.next_beacon);
+ return err;
+ }
+ break;
+ case NL80211_IFTYPE_ADHOC:
+ if (!sdata->vif.bss_conf.ibss_joined)
+ return -EINVAL;
+
+ if (params->chandef.width != sdata->u.ibss.chandef.width)
+ return -EINVAL;
+
+ switch (params->chandef.width) {
+ case NL80211_CHAN_WIDTH_40:
+ if (cfg80211_get_chandef_type(&params->chandef) !=
+ cfg80211_get_chandef_type(&sdata->u.ibss.chandef))
+ return -EINVAL;
+ case NL80211_CHAN_WIDTH_5:
+ case NL80211_CHAN_WIDTH_10:
+ case NL80211_CHAN_WIDTH_20_NOHT:
+ case NL80211_CHAN_WIDTH_20:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* changes into another band are not supported */
+ if (sdata->u.ibss.chandef.chan->band !=
+ params->chandef.chan->band)
+ return -EINVAL;
+
+ err = ieee80211_ibss_csa_beacon(sdata, params);
+ if (err < 0)
+ return err;
break;
default:
return -EOPNOTSUPP;
}

- sdata->u.ap.next_beacon = cfg80211_beacon_dup(&params->beacon_after);
- if (!sdata->u.ap.next_beacon)
- return -ENOMEM;
-
- sdata->csa_counter_offset_beacon = params->counter_offset_beacon;
- sdata->csa_counter_offset_presp = params->counter_offset_presp;
sdata->csa_radar_required = params->radar_required;

if (params->block_tx)
@@ -2944,10 +2985,6 @@ static int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
IEEE80211_MAX_QUEUE_MAP,
IEEE80211_QUEUE_STOP_REASON_CSA);

- err = ieee80211_assign_beacon(sdata, &params->beacon_csa);
- if (err < 0)
- return err;
-
local->csa_chandef = params->chandef;
sdata->vif.csa_active = true;

@@ -3001,7 +3038,8 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
need_offchan = true;
if (!ieee80211_is_action(mgmt->frame_control) ||
mgmt->u.action.category == WLAN_CATEGORY_PUBLIC ||
- mgmt->u.action.category == WLAN_CATEGORY_SELF_PROTECTED)
+ mgmt->u.action.category == WLAN_CATEGORY_SELF_PROTECTED ||
+ mgmt->u.action.category == WLAN_CATEGORY_SPECTRUM_MGMT)
break;
rcu_read_lock();
sta = sta_info_get(sdata, mgmt->da);
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 29f1a7b..4a10e00 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -34,12 +34,15 @@

#define IEEE80211_IBSS_MAX_STA_ENTRIES 128

+static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata);
+
static struct beacon_data *
ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
const int beacon_int, const u32 basic_rates,
const u16 capability, u64 tsf,
struct cfg80211_chan_def *chandef,
- bool *have_higher_than_11mbit)
+ bool *have_higher_than_11mbit,
+ struct cfg80211_csa_settings *csa_settings)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
@@ -59,6 +62,7 @@ ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
2 + 8 /* max Supported Rates */ +
3 /* max DS params */ +
4 /* IBSS params */ +
+ 5 /* Channel Switch Announcement */ +
2 + (IEEE80211_MAX_SUPP_RATES - 8) +
2 + sizeof(struct ieee80211_ht_cap) +
2 + sizeof(struct ieee80211_ht_operation) +
@@ -135,6 +139,16 @@ ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
*pos++ = 0;
*pos++ = 0;

+ if (csa_settings) {
+ *pos++ = WLAN_EID_CHANNEL_SWITCH;
+ *pos++ = 3;
+ *pos++ = csa_settings->block_tx ? 1 : 0;
+ *pos++ = ieee80211_frequency_to_channel(
+ csa_settings->chandef.chan->center_freq);
+ sdata->csa_counter_offset_beacon = (pos - presp->head);
+ *pos++ = csa_settings->count;
+ }
+
/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
if (rates_n > 8) {
*pos++ = WLAN_EID_EXT_SUPP_RATES;
@@ -273,7 +287,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,

presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
capability, tsf, &chandef,
- &have_higher_than_11mbit);
+ &have_higher_than_11mbit, NULL);
if (!presp)
return;

@@ -391,6 +405,110 @@ static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
tsf, false);
}

+/* must hold sdata lock */
+int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
+ struct cfg80211_csa_settings *csa_settings)
+{
+ struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+ struct beacon_data *presp, *old_presp;
+ struct cfg80211_bss *cbss;
+ const struct cfg80211_bss_ies *ies;
+ u16 capability;
+ u64 tsf;
+ int ret = 0;
+
+ sdata_assert_lock(sdata);
+
+ capability = WLAN_CAPABILITY_IBSS;
+
+ if (ifibss->privacy)
+ capability |= WLAN_CAPABILITY_PRIVACY;
+
+ cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
+ ifibss->bssid, ifibss->ssid,
+ ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
+ WLAN_CAPABILITY_PRIVACY,
+ capability);
+
+ if (WARN_ON(!cbss)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ rcu_read_lock();
+ ies = rcu_dereference(cbss->ies);
+ tsf = ies->tsf;
+ rcu_read_unlock();
+ cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
+
+ old_presp = rcu_dereference_protected(ifibss->presp,
+ lockdep_is_held(&sdata->wdev.mtx));
+
+ presp = ieee80211_ibss_build_presp(sdata,
+ sdata->vif.bss_conf.beacon_int,
+ sdata->vif.bss_conf.basic_rates,
+ capability, tsf, &ifibss->chandef,
+ NULL, csa_settings);
+ if (!presp) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ rcu_assign_pointer(ifibss->presp, presp);
+ if (old_presp)
+ kfree_rcu(old_presp, rcu_head);
+
+ ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
+ out:
+ return ret;
+}
+
+int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+ struct cfg80211_bss *cbss;
+ int err;
+ u16 capability;
+
+ sdata_lock(sdata);
+ /* update cfg80211 bss information with the new channel */
+ if (!is_zero_ether_addr(ifibss->bssid)) {
+ capability = WLAN_CAPABILITY_IBSS;
+
+ if (ifibss->privacy)
+ capability |= WLAN_CAPABILITY_PRIVACY;
+
+ cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
+ ifibss->chandef.chan,
+ ifibss->bssid, ifibss->ssid,
+ ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
+ WLAN_CAPABILITY_PRIVACY,
+ capability);
+ /* XXX: should not really modify cfg80211 data */
+ if (cbss) {
+ cbss->channel = sdata->local->csa_chandef.chan;
+ cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
+ }
+ }
+
+ ifibss->chandef = sdata->local->csa_chandef;
+
+ /* generate the beacon */
+ err = ieee80211_ibss_csa_beacon(sdata, NULL);
+ sdata_unlock(sdata);
+ if (err < 0)
+ return err;
+
+ return 0;
+}
+
+void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+
+ cancel_work_sync(&ifibss->csa_connection_drop_work);
+}
+
static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
__acquires(RCU)
{
@@ -474,6 +592,265 @@ ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
return ieee80211_ibss_finish_sta(sta);
}

+static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+ struct ieee80211_local *local = sdata->local;
+ struct cfg80211_bss *cbss;
+ struct beacon_data *presp;
+ struct sta_info *sta;
+ int active_ibss;
+ u16 capability;
+
+ active_ibss = ieee80211_sta_active_ibss(sdata);
+
+ if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
+ capability = WLAN_CAPABILITY_IBSS;
+
+ if (ifibss->privacy)
+ capability |= WLAN_CAPABILITY_PRIVACY;
+
+ cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
+ ifibss->bssid, ifibss->ssid,
+ ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
+ WLAN_CAPABILITY_PRIVACY,
+ capability);
+
+ if (cbss) {
+ cfg80211_unlink_bss(local->hw.wiphy, cbss);
+ cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
+ }
+ }
+
+ ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
+
+ sta_info_flush(sdata);
+
+ spin_lock_bh(&ifibss->incomplete_lock);
+ while (!list_empty(&ifibss->incomplete_stations)) {
+ sta = list_first_entry(&ifibss->incomplete_stations,
+ struct sta_info, list);
+ list_del(&sta->list);
+ spin_unlock_bh(&ifibss->incomplete_lock);
+
+ sta_info_free(local, sta);
+ spin_lock_bh(&ifibss->incomplete_lock);
+ }
+ spin_unlock_bh(&ifibss->incomplete_lock);
+
+ netif_carrier_off(sdata->dev);
+
+ sdata->vif.bss_conf.ibss_joined = false;
+ sdata->vif.bss_conf.ibss_creator = false;
+ sdata->vif.bss_conf.enable_beacon = false;
+ sdata->vif.bss_conf.ssid_len = 0;
+
+ /* remove beacon */
+ presp = rcu_dereference_protected(ifibss->presp,
+ lockdep_is_held(&sdata->wdev.mtx));
+ RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
+ if (presp)
+ kfree_rcu(presp, rcu_head);
+
+ clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
+ ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
+ BSS_CHANGED_IBSS);
+}
+
+static void ieee80211_csa_connection_drop_work(struct work_struct *work)
+{
+ struct ieee80211_sub_if_data *sdata =
+ container_of(work, struct ieee80211_sub_if_data,
+ u.ibss.csa_connection_drop_work);
+
+ ieee80211_ibss_disconnect(sdata);
+ synchronize_rcu();
+ skb_queue_purge(&sdata->skb_queue);
+
+ /* trigger a scan to find another IBSS network to join */
+ ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+}
+
+static bool
+ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
+ struct ieee802_11_elems *elems,
+ bool beacon)
+{
+ struct cfg80211_csa_settings params;
+ struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+ struct ieee80211_chanctx_conf *chanctx_conf;
+ struct ieee80211_chanctx *chanctx;
+ enum nl80211_channel_type ch_type;
+ int err, num_chanctx;
+ u32 sta_flags;
+ u8 mode;
+
+ if (sdata->vif.csa_active)
+ return true;
+
+ if (!sdata->vif.bss_conf.ibss_joined)
+ return false;
+
+ sta_flags = IEEE80211_STA_DISABLE_VHT;
+ switch (ifibss->chandef.width) {
+ case NL80211_CHAN_WIDTH_5:
+ case NL80211_CHAN_WIDTH_10:
+ case NL80211_CHAN_WIDTH_20_NOHT:
+ sta_flags |= IEEE80211_STA_DISABLE_HT;
+ /* fall through */
+ case NL80211_CHAN_WIDTH_20:
+ sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
+ break;
+ default:
+ break;
+ }
+
+ memset(&params, 0, sizeof(params));
+ err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
+ ifibss->chandef.chan->band,
+ sta_flags, &params.count,
+ &mode, &params.chandef);
+
+ /* can't switch to destination channel, fail */
+ if (err < 0)
+ goto disconnect;
+
+ /* did not contain a CSA */
+ if (err)
+ return false;
+
+ if (ifibss->chandef.chan->band != params.chandef.chan->band)
+ goto disconnect;
+
+ switch (ifibss->chandef.width) {
+ case NL80211_CHAN_WIDTH_20_NOHT:
+ case NL80211_CHAN_WIDTH_20:
+ case NL80211_CHAN_WIDTH_40:
+ /* keep our current HT mode (HT20/HT40+/HT40-), even if
+ * another mode has been announced. The mode is not adopted
+ * within the beacon while doing CSA and we should therefore
+ * keep the mode which we announce.
+ */
+ ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
+ cfg80211_chandef_create(&params.chandef, params.chandef.chan,
+ ch_type);
+ break;
+ case NL80211_CHAN_WIDTH_5:
+ case NL80211_CHAN_WIDTH_10:
+ if (WARN_ON(params.chandef.width != ifibss->chandef.width))
+ sdata_info(sdata,
+ "received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
+ params.chandef.chan->center_freq,
+ params.chandef.width,
+ params.chandef.center_freq1,
+ params.chandef.center_freq2);
+ goto disconnect;
+ break;
+ default:
+ /* should not happen, sta_flags should prevent VHT modes. */
+ WARN_ON(1);
+ goto disconnect;
+ }
+
+ if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
+ IEEE80211_CHAN_DISABLED)) {
+ sdata_info(sdata,
+ "network switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
+ params.chandef.chan->center_freq,
+ params.chandef.width,
+ params.chandef.center_freq1,
+ params.chandef.center_freq2);
+ goto disconnect;
+ }
+
+ err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
+ &params.chandef);
+ if (err < 0)
+ goto disconnect;
+ if (err) {
+ params.radar_required = true;
+
+ /* TODO: IBSS-DFS not (yet) supported, disconnect. */
+ goto disconnect;
+ }
+
+ rcu_read_lock();
+ chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+ if (!chanctx_conf) {
+ rcu_read_unlock();
+ goto disconnect;
+ }
+
+ /* don't handle for multi-VIF cases */
+ chanctx = container_of(chanctx_conf, struct ieee80211_chanctx, conf);
+ if (chanctx->refcount > 1) {
+ rcu_read_unlock();
+ goto disconnect;
+ }
+ num_chanctx = 0;
+ list_for_each_entry_rcu(chanctx, &sdata->local->chanctx_list, list)
+ num_chanctx++;
+
+ if (num_chanctx > 1) {
+ rcu_read_unlock();
+ goto disconnect;
+ }
+ rcu_read_unlock();
+
+ /* all checks done, now perform the channel switch. */
+ ibss_dbg(sdata,
+ "received channel switch announcement to go to channel %d MHz\n",
+ params.chandef.chan->center_freq);
+
+ params.block_tx = !!mode;
+
+ ieee80211_ibss_csa_beacon(sdata, &params);
+ sdata->csa_radar_required = params.radar_required;
+
+ if (params.block_tx)
+ ieee80211_stop_queues_by_reason(&sdata->local->hw,
+ IEEE80211_MAX_QUEUE_MAP,
+ IEEE80211_QUEUE_STOP_REASON_CSA);
+
+ sdata->local->csa_chandef = params.chandef;
+ sdata->vif.csa_active = true;
+
+ ieee80211_bss_info_change_notify(sdata, err);
+ drv_channel_switch_beacon(sdata, &params.chandef);
+
+ return true;
+disconnect:
+ ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
+ ieee80211_queue_work(&sdata->local->hw,
+ &ifibss->csa_connection_drop_work);
+
+ return true;
+}
+
+static void
+ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt, size_t len,
+ struct ieee80211_rx_status *rx_status,
+ struct ieee802_11_elems *elems)
+{
+ int required_len;
+
+ if (len < IEEE80211_MIN_ACTION_SIZE + 1)
+ return;
+
+ /* CSA is the only action we handle for now */
+ if (mgmt->u.action.u.measurement.action_code !=
+ WLAN_ACTION_SPCT_CHL_SWITCH)
+ return;
+
+ required_len = IEEE80211_MIN_ACTION_SIZE +
+ sizeof(mgmt->u.action.u.chan_switch);
+ if (len < required_len)
+ return;
+
+ ieee80211_ibss_process_chanswitch(sdata, elems, false);
+}
+
static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len)
@@ -636,10 +1013,6 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,

/* check if we need to merge IBSS */

- /* we use a fixed BSSID */
- if (sdata->u.ibss.fixed_bssid)
- goto put_bss;
-
/* not an IBSS */
if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
goto put_bss;
@@ -655,10 +1028,18 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
sdata->u.ibss.ssid_len))
goto put_bss;

+ /* process channel switch */
+ if (ieee80211_ibss_process_chanswitch(sdata, elems, true))
+ goto put_bss;
+
/* same BSSID */
if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
goto put_bss;

+ /* we use a fixed BSSID */
+ if (sdata->u.ibss.fixed_bssid)
+ goto put_bss;
+
if (ieee80211_have_rx_timestamp(rx_status)) {
/* time when timestamp field was received */
rx_timestamp =
@@ -1040,6 +1421,8 @@ void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
struct ieee80211_rx_status *rx_status;
struct ieee80211_mgmt *mgmt;
u16 fc;
+ struct ieee802_11_elems elems;
+ int ies_len;

rx_status = IEEE80211_SKB_RXCB(skb);
mgmt = (struct ieee80211_mgmt *) skb->data;
@@ -1065,6 +1448,27 @@ void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
case IEEE80211_STYPE_DEAUTH:
ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
break;
+ case IEEE80211_STYPE_ACTION:
+ switch (mgmt->u.action.category) {
+ case WLAN_CATEGORY_SPECTRUM_MGMT:
+ ies_len = skb->len -
+ offsetof(struct ieee80211_mgmt,
+ u.action.u.chan_switch.variable);
+
+ if (ies_len < 0)
+ break;
+
+ ieee802_11_parse_elems(
+ mgmt->u.action.u.chan_switch.variable,
+ ies_len, true, &elems);
+
+ if (elems.parse_error)
+ break;
+
+ ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len,
+ rx_status, &elems);
+ break;
+ }
}

mgmt_out:
@@ -1131,6 +1535,8 @@ void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
(unsigned long) sdata);
INIT_LIST_HEAD(&ifibss->incomplete_stations);
spin_lock_init(&ifibss->incomplete_lock);
+ INIT_WORK(&ifibss->csa_connection_drop_work,
+ ieee80211_csa_connection_drop_work);
}

/* scan finished notification */
@@ -1229,72 +1635,19 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
- struct ieee80211_local *local = sdata->local;
- struct cfg80211_bss *cbss;
- u16 capability;
- int active_ibss;
- struct sta_info *sta;
- struct beacon_data *presp;

- active_ibss = ieee80211_sta_active_ibss(sdata);
+ ieee80211_ibss_disconnect(sdata);

- if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
- capability = WLAN_CAPABILITY_IBSS;
-
- if (ifibss->privacy)
- capability |= WLAN_CAPABILITY_PRIVACY;
-
- cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
- ifibss->bssid, ifibss->ssid,
- ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
- WLAN_CAPABILITY_PRIVACY,
- capability);
-
- if (cbss) {
- cfg80211_unlink_bss(local->hw.wiphy, cbss);
- cfg80211_put_bss(local->hw.wiphy, cbss);
- }
- }
-
- ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
- memset(ifibss->bssid, 0, ETH_ALEN);
ifibss->ssid_len = 0;
-
- sta_info_flush(sdata);
-
- spin_lock_bh(&ifibss->incomplete_lock);
- while (!list_empty(&ifibss->incomplete_stations)) {
- sta = list_first_entry(&ifibss->incomplete_stations,
- struct sta_info, list);
- list_del(&sta->list);
- spin_unlock_bh(&ifibss->incomplete_lock);
-
- sta_info_free(local, sta);
- spin_lock_bh(&ifibss->incomplete_lock);
- }
- spin_unlock_bh(&ifibss->incomplete_lock);
-
- netif_carrier_off(sdata->dev);
-
+ memset(ifibss->bssid, 0, ETH_ALEN);
/* remove beacon */
kfree(sdata->u.ibss.ie);
- presp = rcu_dereference_protected(ifibss->presp,
- lockdep_is_held(&sdata->wdev.mtx));
- RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);

/* on the next join, re-program HT parameters */
memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa));
memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask));

- sdata->vif.bss_conf.ibss_joined = false;
- sdata->vif.bss_conf.ibss_creator = false;
- sdata->vif.bss_conf.enable_beacon = false;
- sdata->vif.bss_conf.ssid_len = 0;
- clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
- ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
- BSS_CHANGED_IBSS);
synchronize_rcu();
- kfree(presp);

skb_queue_purge(&sdata->skb_queue);

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 1275bde..dbbd124 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -490,6 +490,7 @@ struct ieee80211_if_managed {

struct ieee80211_if_ibss {
struct timer_list timer;
+ struct work_struct csa_connection_drop_work;

unsigned long last_scan_completed;

@@ -1336,6 +1337,7 @@ void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
struct cfg80211_csa_settings *csa_settings);
int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata);
+void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata);

/* mesh code */
void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata);
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 7ca534b..a8bce73 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -763,6 +763,10 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
if (sdata->vif.type == NL80211_IFTYPE_STATION)
ieee80211_mgd_stop(sdata);

+ if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
+ ieee80211_ibss_stop(sdata);
+
+
/*
* Remove all stations associated with this interface.
*
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 0ac7512..59595d6 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2396,7 +2396,8 @@ ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
return RX_DROP_UNUSABLE;

if (!rx->sta && mgmt->u.action.category != WLAN_CATEGORY_PUBLIC &&
- mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED)
+ mgmt->u.action.category != WLAN_CATEGORY_SELF_PROTECTED &&
+ mgmt->u.action.category != WLAN_CATEGORY_SPECTRUM_MGMT)
return RX_DROP_UNUSABLE;

if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
@@ -2560,31 +2561,46 @@ ieee80211_rx_h_action(struct ieee80211_rx_data *rx)

goto queue;
case WLAN_CATEGORY_SPECTRUM_MGMT:
- if (status->band != IEEE80211_BAND_5GHZ)
- break;
-
- if (sdata->vif.type != NL80211_IFTYPE_STATION)
- break;
-
/* verify action_code is present */
if (len < IEEE80211_MIN_ACTION_SIZE + 1)
break;

switch (mgmt->u.action.u.measurement.action_code) {
case WLAN_ACTION_SPCT_MSR_REQ:
+ if (status->band != IEEE80211_BAND_5GHZ)
+ break;
+
if (len < (IEEE80211_MIN_ACTION_SIZE +
sizeof(mgmt->u.action.u.measurement)))
break;
+
+ if (sdata->vif.type != NL80211_IFTYPE_STATION)
+ break;
+
ieee80211_process_measurement_req(sdata, mgmt, len);
goto handled;
- case WLAN_ACTION_SPCT_CHL_SWITCH:
- if (sdata->vif.type != NL80211_IFTYPE_STATION)
+ case WLAN_ACTION_SPCT_CHL_SWITCH: {
+ u8 *bssid;
+ if (len < (IEEE80211_MIN_ACTION_SIZE +
+ sizeof(mgmt->u.action.u.chan_switch)))
break;

- if (!ether_addr_equal(mgmt->bssid, sdata->u.mgd.bssid))
+ if (sdata->vif.type != NL80211_IFTYPE_STATION &&
+ sdata->vif.type != NL80211_IFTYPE_ADHOC)
+ break;
+
+ if (sdata->vif.type == NL80211_IFTYPE_STATION)
+ bssid = sdata->u.mgd.bssid;
+ else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
+ bssid = sdata->u.ibss.bssid;
+ else
+ break;
+
+ if (!ether_addr_equal(mgmt->bssid, bssid))
break;

goto queue;
+ }
}
break;
case WLAN_CATEGORY_SA_QUERY:
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 0e42322..ab5e151 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2353,15 +2353,28 @@ static void ieee80211_update_csa(struct ieee80211_sub_if_data *sdata,
struct probe_resp *resp;
int counter_offset_beacon = sdata->csa_counter_offset_beacon;
int counter_offset_presp = sdata->csa_counter_offset_presp;
+ u8 *beacon_data;
+ size_t beacon_data_len;
+
+ if (sdata->vif.type == NL80211_IFTYPE_AP) {
+ beacon_data = beacon->tail;
+ beacon_data_len = beacon->tail_len;
+ } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
+ beacon_data = beacon->head;
+ beacon_data_len = beacon->head_len;
+ } else {
+ return;
+ }
+ if (WARN_ON(counter_offset_beacon >= beacon_data_len))
+ return;

/* warn if the driver did not check for/react to csa completeness */
- if (WARN_ON(((u8 *)beacon->tail)[counter_offset_beacon] == 0))
+ if (WARN_ON(beacon_data[counter_offset_beacon] == 0))
return;

- ((u8 *)beacon->tail)[counter_offset_beacon]--;
+ beacon_data[counter_offset_beacon]--;

- if (sdata->vif.type == NL80211_IFTYPE_AP &&
- counter_offset_presp) {
+ if (sdata->vif.type == NL80211_IFTYPE_AP && counter_offset_presp) {
rcu_read_lock();
resp = rcu_dereference(sdata->u.ap.probe_resp);

@@ -2396,6 +2409,15 @@ bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
goto out;
beacon_data = beacon->tail;
beacon_data_len = beacon->tail_len;
+ } else if (vif->type == NL80211_IFTYPE_ADHOC) {
+ struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+
+ beacon = rcu_dereference(ifibss->presp);
+ if (!beacon)
+ goto out;
+
+ beacon_data = beacon->head;
+ beacon_data_len = beacon->head_len;
} else {
WARN_ON(1);
goto out;
@@ -2480,6 +2502,10 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
if (!presp)
goto out;

+ if (sdata->vif.csa_active)
+ ieee80211_update_csa(sdata, presp);
+
+
skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
if (!skb)
goto out;
--
1.7.10.4


2013-08-02 15:38:19

by Simon Wunderlich

[permalink] [raw]
Subject: [PATCH 6/7] mac80211: send a CSA action frame when changing channel

IBSS members may not immediately be able to send out their beacon when
performing CSA, therefore also send a CSA action frame.

Signed-off-by: Simon Wunderlich <[email protected]>
Signed-off-by: Mathias Kretschmer <[email protected]>
---
net/mac80211/ibss.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 61 insertions(+)

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 4a10e00..2bd86a2 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -405,6 +405,61 @@ static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
tsf, false);
}

+static int ieee80211_send_action_csa(struct ieee80211_sub_if_data *sdata,
+ struct cfg80211_csa_settings *csa_settings)
+{
+ struct sk_buff *skb;
+ struct ieee80211_mgmt *mgmt;
+ struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
+ struct ieee80211_local *local = sdata->local;
+ int freq;
+ int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.chan_switch) +
+ sizeof(mgmt->u.action.u.chan_switch);
+ u8 *pos;
+
+ skb = dev_alloc_skb(local->tx_headroom + hdr_len +
+ 5 + /* channel switch announcement element */
+ 3); /* secondary channel offset element */
+ if (!skb)
+ return -1;
+
+ skb_reserve(skb, local->tx_headroom);
+ mgmt = (struct ieee80211_mgmt *)skb_put(skb, hdr_len);
+ memset(mgmt, 0, hdr_len);
+ mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+ IEEE80211_STYPE_ACTION);
+
+ eth_broadcast_addr(mgmt->da);
+ memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
+ memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
+ mgmt->u.action.category = WLAN_CATEGORY_SPECTRUM_MGMT;
+ mgmt->u.action.u.chan_switch.action_code = WLAN_ACTION_SPCT_CHL_SWITCH;
+ pos = skb_put(skb, 5);
+ *pos++ = WLAN_EID_CHANNEL_SWITCH; /* EID */
+ *pos++ = 3; /* IE length */
+ *pos++ = csa_settings->block_tx ? 1 : 0; /* CSA mode */
+ freq = csa_settings->chandef.chan->center_freq;
+ *pos++ = ieee80211_frequency_to_channel(freq); /* channel */
+ *pos++ = csa_settings->count; /* count */
+
+ if (csa_settings->chandef.width == NL80211_CHAN_WIDTH_40) {
+ enum nl80211_channel_type ch_type;
+
+ skb_put(skb, 3);
+ *pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET; /* EID */
+ *pos++ = 1; /* IE length */
+ ch_type = cfg80211_get_chandef_type(&csa_settings->chandef);
+ if (ch_type == NL80211_CHAN_HT40PLUS)
+ *pos++ = IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
+ else
+ *pos++ = IEEE80211_HT_PARAM_CHA_SEC_BELOW;
+ }
+
+ ieee80211_tx_skb(sdata, skb);
+ return 0;
+}
+
+
/* must hold sdata lock */
int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
struct cfg80211_csa_settings *csa_settings)
@@ -458,6 +513,12 @@ int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
if (old_presp)
kfree_rcu(old_presp, rcu_head);

+ /* it might not send the beacon for a while. send an action frame
+ * immediately to announce the channel switch.
+ */
+ if (csa_settings)
+ ieee80211_send_action_csa(sdata, csa_settings);
+
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
out:
return ret;
--
1.7.10.4


2013-08-09 13:17:42

by Johannes Berg

[permalink] [raw]
Subject: Re: [PATCH 2/7] mac80211: fix ieee80211_sta_process_chanswitch for 5/10 MHz channels

Applied.

johannes


2013-08-09 13:20:17

by Johannes Berg

[permalink] [raw]
Subject: Re: [PATCH 3/7] mac80211: split off channel switch parsing function

On Fri, 2013-08-02 at 17:38 +0200, Simon Wunderlich wrote:

> sdata_info(sdata,
> + "network switches to unsupported channel (%d MHz), disconnecting\n",
> + new_freq);
> + return -EINVAL;

I don't like these messaging changes - it's actually interesting what
the AP is etc.

johannes


2013-08-09 13:15:44

by Johannes Berg

[permalink] [raw]
Subject: Re: [PATCH 1/7] cfg80211: export cfg80211_chandef_dfs_required

On Fri, 2013-08-02 at 17:38 +0200, Simon Wunderlich wrote:

>
> -/**
> - * cfg80211_chandef_dfs_required - checks if radar detection is required
> - * @wiphy: the wiphy to validate against
> - * @chandef: the channel definition to check
> - * Return: 1 if radar detection is required, 0 if it is not, < 0 on error
> - */
> -int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
> - const struct cfg80211_chan_def *c);
>

Please delete one of the blank lines too :)

johannes


2013-08-09 13:22:29

by Johannes Berg

[permalink] [raw]
Subject: Re: [PATCH 5/7] mac80211: add support for CSA in IBSS mode

On Fri, 2013-08-02 at 17:38 +0200, Simon Wunderlich wrote:

> + if (sdata->vif.type == NL80211_IFTYPE_AP) {

> + } else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {

> + } else {

switch() ?


> + case NL80211_CHAN_WIDTH_10:
> + if (WARN_ON(params.chandef.width != ifibss->chandef.width))

You should really not make a WARN_ON remotely triggerable.

johannes