summaryrefslogtreecommitdiff
path: root/net/mac80211/scan.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/mac80211/scan.c')
-rw-r--r--net/mac80211/scan.c436
1 files changed, 260 insertions, 176 deletions
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 3bf9839f5916..2a8d09ad17ff 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -21,6 +21,7 @@
#include <net/iw_handler.h>
#include "ieee80211_i.h"
+#include "driver-ops.h"
#include "mesh.h"
#define IEEE80211_PROBE_DELAY (HZ / 33)
@@ -202,18 +203,6 @@ ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
return RX_QUEUED;
}
-void ieee80211_scan_failed(struct ieee80211_local *local)
-{
- if (WARN_ON(!local->scan_req))
- return;
-
- /* notify cfg80211 about the failed scan */
- if (local->scan_req != &local->int_scan_req)
- cfg80211_scan_done(local->scan_req, true);
-
- local->scan_req = NULL;
-}
-
/*
* inform AP that we will go to sleep so that it will buffer the frames
* while we scan
@@ -253,7 +242,7 @@ static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
- if (!local->powersave)
+ if (!local->ps_sdata)
ieee80211_send_nullfunc(local, sdata, 0);
else {
/*
@@ -274,51 +263,62 @@ static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data *sdata)
}
}
+static void ieee80211_restore_scan_ies(struct ieee80211_local *local)
+{
+ kfree(local->scan_req->ie);
+ local->scan_req->ie = local->orig_ies;
+ local->scan_req->ie_len = local->orig_ies_len;
+}
+
void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_sub_if_data *sdata;
+ bool was_hw_scan;
- if (WARN_ON(!local->hw_scanning && !local->sw_scanning))
+ mutex_lock(&local->scan_mtx);
+
+ if (WARN_ON(!local->hw_scanning && !local->sw_scanning)) {
+ mutex_unlock(&local->scan_mtx);
return;
+ }
- if (WARN_ON(!local->scan_req))
+ if (WARN_ON(!local->scan_req)) {
+ mutex_unlock(&local->scan_mtx);
return;
+ }
+
+ if (local->hw_scanning)
+ ieee80211_restore_scan_ies(local);
if (local->scan_req != &local->int_scan_req)
cfg80211_scan_done(local->scan_req, aborted);
local->scan_req = NULL;
- local->last_scan_completed = jiffies;
+ was_hw_scan = local->hw_scanning;
+ local->hw_scanning = false;
+ local->sw_scanning = false;
+ local->scan_channel = NULL;
- if (local->hw_scanning) {
- local->hw_scanning = false;
- /*
- * Somebody might have requested channel change during scan
- * that we won't have acted upon, try now. ieee80211_hw_config
- * will set the flag based on actual changes.
- */
- ieee80211_hw_config(local, 0);
- goto done;
- }
+ /* we only have to protect scan_req and hw/sw scan */
+ mutex_unlock(&local->scan_mtx);
- local->sw_scanning = false;
ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
+ if (was_hw_scan)
+ goto done;
netif_tx_lock_bh(local->mdev);
netif_addr_lock(local->mdev);
local->filter_flags &= ~FIF_BCN_PRBRESP_PROMISC;
- local->ops->configure_filter(local_to_hw(local),
- FIF_BCN_PRBRESP_PROMISC,
- &local->filter_flags,
- local->mdev->mc_count,
- local->mdev->mc_list);
+ drv_configure_filter(local, FIF_BCN_PRBRESP_PROMISC,
+ &local->filter_flags,
+ local->mdev->mc_count,
+ local->mdev->mc_list);
netif_addr_unlock(local->mdev);
netif_tx_unlock_bh(local->mdev);
- if (local->ops->sw_scan_complete)
- local->ops->sw_scan_complete(local_to_hw(local));
+ drv_sw_scan_complete(local);
mutex_lock(&local->iflist_mtx);
list_for_each_entry(sdata, &local->interfaces, list) {
@@ -338,18 +338,160 @@ void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
if (sdata->vif.type == NL80211_IFTYPE_AP ||
sdata->vif.type == NL80211_IFTYPE_ADHOC ||
sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
- ieee80211_if_config(sdata,
- IEEE80211_IFCC_BEACON_ENABLED);
+ ieee80211_bss_info_change_notify(
+ sdata, BSS_CHANGED_BEACON_ENABLED);
}
mutex_unlock(&local->iflist_mtx);
done:
+ ieee80211_recalc_idle(local);
ieee80211_mlme_notify_scan_completed(local);
ieee80211_ibss_notify_scan_completed(local);
ieee80211_mesh_notify_scan_completed(local);
}
EXPORT_SYMBOL(ieee80211_scan_completed);
+static int ieee80211_start_sw_scan(struct ieee80211_local *local)
+{
+ struct ieee80211_sub_if_data *sdata;
+
+ /*
+ * Hardware/driver doesn't support hw_scan, so use software
+ * scanning instead. First send a nullfunc frame with power save
+ * bit on so that AP will buffer the frames for us while we are not
+ * listening, then send probe requests to each channel and wait for
+ * the responses. After all channels are scanned, tune back to the
+ * original channel and send a nullfunc frame with power save bit
+ * off to trigger the AP to send us all the buffered frames.
+ *
+ * Note that while local->sw_scanning is true everything else but
+ * nullfunc frames and probe requests will be dropped in
+ * ieee80211_tx_h_check_assoc().
+ */
+ drv_sw_scan_start(local);
+
+ mutex_lock(&local->iflist_mtx);
+ list_for_each_entry(sdata, &local->interfaces, list) {
+ if (!netif_running(sdata->dev))
+ continue;
+
+ /* disable beaconing */
+ if (sdata->vif.type == NL80211_IFTYPE_AP ||
+ sdata->vif.type == NL80211_IFTYPE_ADHOC ||
+ sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
+ ieee80211_bss_info_change_notify(
+ sdata, BSS_CHANGED_BEACON_ENABLED);
+
+ if (sdata->vif.type == NL80211_IFTYPE_STATION) {
+ if (sdata->u.mgd.flags & IEEE80211_STA_ASSOCIATED) {
+ netif_tx_stop_all_queues(sdata->dev);
+ ieee80211_scan_ps_enable(sdata);
+ }
+ } else
+ netif_tx_stop_all_queues(sdata->dev);
+ }
+ mutex_unlock(&local->iflist_mtx);
+
+ local->scan_state = SCAN_SET_CHANNEL;
+ local->scan_channel_idx = 0;
+
+ netif_addr_lock_bh(local->mdev);
+ local->filter_flags |= FIF_BCN_PRBRESP_PROMISC;
+ drv_configure_filter(local, FIF_BCN_PRBRESP_PROMISC,
+ &local->filter_flags,
+ local->mdev->mc_count,
+ local->mdev->mc_list);
+ netif_addr_unlock_bh(local->mdev);
+
+ /* TODO: start scan as soon as all nullfunc frames are ACKed */
+ queue_delayed_work(local->hw.workqueue, &local->scan_work,
+ IEEE80211_CHANNEL_TIME);
+
+ return 0;
+}
+
+
+static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
+ struct cfg80211_scan_request *req)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+ int rc;
+
+ if (local->scan_req)
+ return -EBUSY;
+
+ if (local->ops->hw_scan) {
+ u8 *ies;
+ int ielen;
+
+ ies = kmalloc(2 + IEEE80211_MAX_SSID_LEN +
+ local->scan_ies_len + req->ie_len, GFP_KERNEL);
+ if (!ies)
+ return -ENOMEM;
+
+ ielen = ieee80211_build_preq_ies(local, ies,
+ req->ie, req->ie_len);
+ local->orig_ies = req->ie;
+ local->orig_ies_len = req->ie_len;
+ req->ie = ies;
+ req->ie_len = ielen;
+ }
+
+ local->scan_req = req;
+ local->scan_sdata = sdata;
+
+ if (req != &local->int_scan_req &&
+ sdata->vif.type == NL80211_IFTYPE_STATION &&
+ (ifmgd->state == IEEE80211_STA_MLME_DIRECT_PROBE ||
+ ifmgd->state == IEEE80211_STA_MLME_AUTHENTICATE ||
+ ifmgd->state == IEEE80211_STA_MLME_ASSOCIATE)) {
+ /* actually wait for the assoc to finish/time out */
+ set_bit(IEEE80211_STA_REQ_SCAN, &ifmgd->request);
+ return 0;
+ }
+
+ if (local->ops->hw_scan)
+ local->hw_scanning = true;
+ else
+ local->sw_scanning = true;
+ /*
+ * Kicking off the scan need not be protected,
+ * only the scan variable stuff, since now
+ * local->scan_req is assigned and other callers
+ * will abort their scan attempts.
+ *
+ * This avoids getting a scan_mtx -> iflist_mtx
+ * dependency, so that the scan completed calls
+ * have more locking freedom.
+ */
+
+ ieee80211_recalc_idle(local);
+ mutex_unlock(&local->scan_mtx);
+
+ if (local->ops->hw_scan)
+ rc = drv_hw_scan(local, local->scan_req);
+ else
+ rc = ieee80211_start_sw_scan(local);
+
+ mutex_lock(&local->scan_mtx);
+
+ if (rc) {
+ if (local->ops->hw_scan) {
+ local->hw_scanning = false;
+ ieee80211_restore_scan_ies(local);
+ } else
+ local->sw_scanning = false;
+
+ ieee80211_recalc_idle(local);
+
+ local->scan_req = NULL;
+ local->scan_sdata = NULL;
+ }
+
+ return rc;
+}
+
void ieee80211_scan_work(struct work_struct *work)
{
struct ieee80211_local *local =
@@ -359,17 +501,41 @@ void ieee80211_scan_work(struct work_struct *work)
int skip, i;
unsigned long next_delay = 0;
+ mutex_lock(&local->scan_mtx);
+ if (!sdata || !local->scan_req) {
+ mutex_unlock(&local->scan_mtx);
+ return;
+ }
+
+ if (local->scan_req && !(local->sw_scanning || local->hw_scanning)) {
+ struct cfg80211_scan_request *req = local->scan_req;
+ int rc;
+
+ local->scan_req = NULL;
+
+ rc = __ieee80211_start_scan(sdata, req);
+ mutex_unlock(&local->scan_mtx);
+
+ if (rc)
+ ieee80211_scan_completed(&local->hw, true);
+ return;
+ }
+
+ mutex_unlock(&local->scan_mtx);
+
/*
* Avoid re-scheduling when the sdata is going away.
*/
- if (!netif_running(sdata->dev))
+ if (!netif_running(sdata->dev)) {
+ ieee80211_scan_completed(&local->hw, true);
return;
+ }
switch (local->scan_state) {
case SCAN_SET_CHANNEL:
/* if no more bands/channels left, complete scan */
if (local->scan_channel_idx >= local->scan_req->n_channels) {
- ieee80211_scan_completed(local_to_hw(local), false);
+ ieee80211_scan_completed(&local->hw, false);
return;
}
skip = 0;
@@ -393,24 +559,39 @@ void ieee80211_scan_work(struct work_struct *work)
if (skip)
break;
- next_delay = IEEE80211_PROBE_DELAY +
- usecs_to_jiffies(local->hw.channel_change_time);
+ /*
+ * Probe delay is used to update the NAV, cf. 11.1.3.2.2
+ * (which unfortunately doesn't say _why_ step a) is done,
+ * but it waits for the probe delay or until a frame is
+ * received - and the received frame would update the NAV).
+ * For now, we do not support waiting until a frame is
+ * received.
+ *
+ * In any case, it is not necessary for a passive scan.
+ */
+ if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN ||
+ !local->scan_req->n_ssids) {
+ next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
+ break;
+ }
+
+ next_delay = IEEE80211_PROBE_DELAY;
local->scan_state = SCAN_SEND_PROBE;
break;
case SCAN_SEND_PROBE:
- next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
- local->scan_state = SCAN_SET_CHANNEL;
-
- if (local->scan_channel->flags & IEEE80211_CHAN_PASSIVE_SCAN ||
- !local->scan_req->n_ssids)
- break;
for (i = 0; i < local->scan_req->n_ssids; i++)
ieee80211_send_probe_req(
sdata, NULL,
local->scan_req->ssids[i].ssid,
local->scan_req->ssids[i].ssid_len,
local->scan_req->ie, local->scan_req->ie_len);
+
+ /*
+ * After sending probe requests, wait for probe responses
+ * on the channel.
+ */
next_delay = IEEE80211_CHANNEL_TIME;
+ local->scan_state = SCAN_SET_CHANNEL;
break;
}
@@ -418,150 +599,53 @@ void ieee80211_scan_work(struct work_struct *work)
next_delay);
}
-
-int ieee80211_start_scan(struct ieee80211_sub_if_data *scan_sdata,
- struct cfg80211_scan_request *req)
+int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
+ struct cfg80211_scan_request *req)
{
- struct ieee80211_local *local = scan_sdata->local;
- struct ieee80211_sub_if_data *sdata;
-
- if (!req)
- return -EINVAL;
-
- if (local->scan_req && local->scan_req != req)
- return -EBUSY;
-
- local->scan_req = req;
-
- /* MLME-SCAN.request (page 118) page 144 (11.1.3.1)
- * BSSType: INFRASTRUCTURE, INDEPENDENT, ANY_BSS
- * BSSID: MACAddress
- * SSID
- * ScanType: ACTIVE, PASSIVE
- * ProbeDelay: delay (in microseconds) to be used prior to transmitting
- * a Probe frame during active scanning
- * ChannelList
- * MinChannelTime (>= ProbeDelay), in TU
- * MaxChannelTime: (>= MinChannelTime), in TU
- */
-
- /* MLME-SCAN.confirm
- * BSSDescriptionSet
- * ResultCode: SUCCESS, INVALID_PARAMETERS
- */
-
- if (local->sw_scanning || local->hw_scanning) {
- if (local->scan_sdata == scan_sdata)
- return 0;
- return -EBUSY;
- }
-
- if (local->ops->hw_scan) {
- int rc;
-
- local->hw_scanning = true;
- rc = local->ops->hw_scan(local_to_hw(local), req);
- if (rc) {
- local->hw_scanning = false;
- return rc;
- }
- local->scan_sdata = scan_sdata;
- return 0;
- }
-
- /*
- * Hardware/driver doesn't support hw_scan, so use software
- * scanning instead. First send a nullfunc frame with power save
- * bit on so that AP will buffer the frames for us while we are not
- * listening, then send probe requests to each channel and wait for
- * the responses. After all channels are scanned, tune back to the
- * original channel and send a nullfunc frame with power save bit
- * off to trigger the AP to send us all the buffered frames.
- *
- * Note that while local->sw_scanning is true everything else but
- * nullfunc frames and probe requests will be dropped in
- * ieee80211_tx_h_check_assoc().
- */
- local->sw_scanning = true;
- if (local->ops->sw_scan_start)
- local->ops->sw_scan_start(local_to_hw(local));
+ int res;
- mutex_lock(&local->iflist_mtx);
- list_for_each_entry(sdata, &local->interfaces, list) {
- if (!netif_running(sdata->dev))
- continue;
+ mutex_lock(&sdata->local->scan_mtx);
+ res = __ieee80211_start_scan(sdata, req);
+ mutex_unlock(&sdata->local->scan_mtx);
- /* disable beaconing */
- if (sdata->vif.type == NL80211_IFTYPE_AP ||
- sdata->vif.type == NL80211_IFTYPE_ADHOC ||
- sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
- ieee80211_if_config(sdata,
- IEEE80211_IFCC_BEACON_ENABLED);
+ return res;
+}
- if (sdata->vif.type == NL80211_IFTYPE_STATION) {
- if (sdata->u.mgd.flags & IEEE80211_STA_ASSOCIATED) {
- netif_tx_stop_all_queues(sdata->dev);
- ieee80211_scan_ps_enable(sdata);
- }
- } else
- netif_tx_stop_all_queues(sdata->dev);
- }
- mutex_unlock(&local->iflist_mtx);
+int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata,
+ const u8 *ssid, u8 ssid_len)
+{
+ struct ieee80211_local *local = sdata->local;
+ int ret = -EBUSY;
- local->scan_state = SCAN_SET_CHANNEL;
- local->scan_channel_idx = 0;
- local->scan_sdata = scan_sdata;
- local->scan_req = req;
+ mutex_lock(&local->scan_mtx);
- netif_addr_lock_bh(local->mdev);
- local->filter_flags |= FIF_BCN_PRBRESP_PROMISC;
- local->ops->configure_filter(local_to_hw(local),
- FIF_BCN_PRBRESP_PROMISC,
- &local->filter_flags,
- local->mdev->mc_count,
- local->mdev->mc_list);
- netif_addr_unlock_bh(local->mdev);
+ /* busy scanning */
+ if (local->scan_req)
+ goto unlock;
- /* TODO: start scan as soon as all nullfunc frames are ACKed */
- queue_delayed_work(local->hw.workqueue, &local->scan_work,
- IEEE80211_CHANNEL_TIME);
+ memcpy(local->int_scan_req.ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
+ local->int_scan_req.ssids[0].ssid_len = ssid_len;
- return 0;
+ ret = __ieee80211_start_scan(sdata, &sdata->local->int_scan_req);
+ unlock:
+ mutex_unlock(&local->scan_mtx);
+ return ret;
}
-
-int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
- struct cfg80211_scan_request *req)
+void ieee80211_scan_cancel(struct ieee80211_local *local)
{
- struct ieee80211_local *local = sdata->local;
- struct ieee80211_if_managed *ifmgd;
-
- if (!req)
- return -EINVAL;
+ bool swscan;
- if (local->scan_req && local->scan_req != req)
- return -EBUSY;
-
- local->scan_req = req;
-
- if (sdata->vif.type != NL80211_IFTYPE_STATION)
- return ieee80211_start_scan(sdata, req);
+ cancel_delayed_work_sync(&local->scan_work);
/*
- * STA has a state machine that might need to defer scanning
- * while it's trying to associate/authenticate, therefore we
- * queue it up to the state machine in that case.
+ * Only call this function when a scan can't be
+ * queued -- mostly at suspend under RTNL.
*/
+ mutex_lock(&local->scan_mtx);
+ swscan = local->sw_scanning;
+ mutex_unlock(&local->scan_mtx);
- if (local->sw_scanning || local->hw_scanning) {
- if (local->scan_sdata == sdata)
- return 0;
- return -EBUSY;
- }
-
- ifmgd = &sdata->u.mgd;
- set_bit(IEEE80211_STA_REQ_SCAN, &ifmgd->request);
- queue_work(local->hw.workqueue, &ifmgd->work);
-
- return 0;
+ if (swscan)
+ ieee80211_scan_completed(&local->hw, true);
}