From: Victor Goldenshtein <victorg@xxxxxx>
Add NL80211_CMD_AP_CH_SWITCH command which
triggers an AP channel switch process.
Usermode notified about channel switch complete
event with NL80211_CMD_CH_SWITCH_NOTIFY.
Usermode (hostapd) is responsible to update the
channel switch announcement IE in the beacon
prior and after the channel switch operation.
Signed-off-by: Victor Goldenshtein <victorg@xxxxxx>
[Changes:
* change to chandef
* stop ap when moving to a DFS channel
* document channel switch new behaviour
* rebase on current master]
Signed-off-by: Simon Wunderlich <siwu@xxxxxxxxxxxxxxxxxx>
---
include/net/cfg80211.h | 38 +++++++++++++++++++++++-
include/uapi/linux/nl80211.h | 29 ++++++++++++++++++
net/wireless/mlme.c | 8 +++--
net/wireless/nl80211.c | 67 ++++++++++++++++++++++++++++++++++++++++--
net/wireless/nl80211.h | 3 +-
5 files changed, 139 insertions(+), 6 deletions(-)
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 3740b57..7cfa08d 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -331,6 +331,36 @@ struct cfg80211_chan_def {
};
/**
+ * struct ieee80211_ap_ch_switch - holds the ap channel switch data
+ *
+ * The information provided in this structure is required for the ap channel
+ * switch operation.
+ *
+ * @timestamp: value in microseconds of the 64-bit Time Synchronization
+ * Function (TSF) timer when the frame containing the channel switch
+ * announcement was received. This is simply the rx.mactime parameter
+ * the driver passed into mac80211.
+ * @block_tx: Indicates whether transmission must be blocked before the
+ * scheduled channel switch, setting this flag will rise Channel Switch
+ * Mode bit in the AP CSA IE which means that all STAs in a BSS shall
+ * stop transmitting immediately.
+ * @post_switch_block_tx: Indicates whether the AP transmission must be blocked
+ * after the scheduled channel switch, this should be set if the target
+ * channel is DFS channel.
+ * @chandef: the new channel to switch to
+ * @count: the number of TBTT's until the channel switch event
+ */
+struct ieee80211_ap_ch_switch {
+ u64 timestamp;
+ bool block_tx;
+ bool post_switch_block_tx;
+ struct cfg80211_chan_def chandef;
+ u8 count;
+};
+
+
+
+/**
* cfg80211_get_chandef_type - return old channel type from chandef
* @chandef: the channel definition
*
@@ -1773,6 +1803,7 @@ struct cfg80211_gtk_rekey_data {
* @stop_p2p_device: Stop the given P2P device.
*
* @start_radar_detection: Start radar detection in the driver.
+ * @ap_channel_switch: Perform AP channel switch.
*/
struct cfg80211_ops {
int (*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow);
@@ -1997,6 +2028,9 @@ struct cfg80211_ops {
int (*start_radar_detection)(struct wiphy *wiphy,
struct net_device *dev,
struct cfg80211_chan_def *chandef);
+ int (*ap_channel_switch)(struct wiphy *wiphy,
+ struct net_device *dev,
+ struct ieee80211_ap_ch_switch *ap_ch_sw);
};
/*
@@ -3723,11 +3757,13 @@ bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
* cfg80211_ch_switch_notify - update wdev channel and notify userspace
* @dev: the device which switched channels
* @chandef: the new channel definition
+ * @stop_ap: stop the access point
*
* Acquires wdev_lock, so must only be called from sleepable driver context!
*/
void cfg80211_ch_switch_notify(struct net_device *dev,
- struct cfg80211_chan_def *chandef);
+ struct cfg80211_chan_def *chandef,
+ bool stop_ap);
/*
* cfg80211_tdls_oper_request - request userspace to perform TDLS operation
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 2303f86..7a98735 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -589,6 +589,21 @@
* @NL80211_CMD_RADAR_DETECT: Start radar detection in the driver/HW. Once
* radar detected usermode notified with this event.
*
+ * @NL80211_CMD_AP_CH_SWITCH: Perform a channel switch in the driver (for
+ * AP/GO). Userspace daemon is responsible to update the CSA IE in the
+ * beacon prior and after the channel switch operation. Userspace notified
+ * about channel switch complete event with %NL80211_CMD_CH_SWITCH_NOTIFY.
+ * %NL80211_ATTR_WIPHY_FREQ is used to specify the new channel frequency.
+ * %NL80211_ATTR_CH_SWITCH_BLOCK_TX is used to specify that tx must be
+ * blocked on the current channel. %NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX
+ * is used to specify that tx must be blocked on the target channel.
+ * %NL80211_FREQ_ATTR_CH_SWITCH_COUNT to specify the number of TBTT's until
+ * the device switches to the target channel.
+ * If the target channel is a DFS channel, the AP will be stopped (stop_ap)
+ * and NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX will be sent back with the
+ * %NL80211_CMD_CH_SWITCH_NOTIFY event to reflect this. Userspace may then
+ * start another Channel Availability Check (CAC) to use the new channel.
+ *
* @NL80211_CMD_MAX: highest used command number
* @__NL80211_CMD_AFTER_LAST: internal use
*/
@@ -740,6 +755,7 @@ enum nl80211_commands {
NL80211_CMD_SET_MCAST_RATE,
NL80211_CMD_RADAR_DETECT,
+ NL80211_CMD_AP_CH_SWITCH,
/* add new commands above here */
@@ -1314,6 +1330,14 @@ enum nl80211_commands {
* START_AP and SET_BSS commands. This can have the values 0 or 1;
* if not given in START_AP 0 is assumed, if not given in SET_BSS
* no change is made.
+ * @NL80211_ATTR_CH_SWITCH_COUNT: u32 attribute specifying the number of TBTT's
+ * until the channel switch event.
+ * @NL80211_ATTR_CH_SWITCH_BLOCK_TX: flag attribute specifying that transmission
+ * must be blocked on the current channel (before the channel switch
+ * operation).
+ * @NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX: flag attribute specifying that
+ * transmission must be blocked on the target channel after the channel
+ * switch operation, should be set if the target channel is DFS channel.
*
* @NL80211_ATTR_MAX: highest attribute number currently defined
* @__NL80211_ATTR_AFTER_LAST: internal use
@@ -1585,6 +1609,10 @@ enum nl80211_attrs {
NL80211_ATTR_P2P_CTWINDOW,
NL80211_ATTR_P2P_OPPPS,
+ NL80211_ATTR_CH_SWITCH_COUNT,
+ NL80211_ATTR_CH_SWITCH_BLOCK_TX,
+ NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX,
+
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
@@ -3165,6 +3193,7 @@ enum nl80211_feature_flags {
NL80211_FEATURE_P2P_GO_CTWIN = 1 << 11,
NL80211_FEATURE_P2P_GO_OPPPS = 1 << 12,
NL80211_FEATURE_20MHZ_DFS = 1 << 13,
+ NL80211_FEATURE_AP_CH_SWITCH = 1 << 14,
};
/**
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 02666e3..8cdbdd0e 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -989,7 +989,8 @@ void cfg80211_pmksa_candidate_notify(struct net_device *dev, int index,
EXPORT_SYMBOL(cfg80211_pmksa_candidate_notify);
void cfg80211_ch_switch_notify(struct net_device *dev,
- struct cfg80211_chan_def *chandef)
+ struct cfg80211_chan_def *chandef,
+ bool stop_ap)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct wiphy *wiphy = wdev->wiphy;
@@ -997,6 +998,9 @@ void cfg80211_ch_switch_notify(struct net_device *dev,
trace_cfg80211_ch_switch_notify(dev, chandef);
+ if (stop_ap)
+ cfg80211_stop_ap(rdev, dev);
+
wdev_lock(wdev);
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_AP &&
@@ -1004,7 +1008,7 @@ void cfg80211_ch_switch_notify(struct net_device *dev,
goto out;
wdev->channel = chandef->chan;
- nl80211_ch_switch_notify(rdev, dev, chandef, GFP_KERNEL);
+ nl80211_ch_switch_notify(rdev, dev, chandef, stop_ap, GFP_KERNEL);
out:
wdev_unlock(wdev);
return;
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index d49c0c2..898d829 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -365,6 +365,9 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
[NL80211_ATTR_SCAN_FLAGS] = { .type = NLA_U32 },
[NL80211_ATTR_P2P_CTWINDOW] = { .type = NLA_U8 },
[NL80211_ATTR_P2P_OPPPS] = { .type = NLA_U8 },
+ [NL80211_ATTR_CH_SWITCH_COUNT] = { .type = NLA_U32 },
+ [NL80211_ATTR_CH_SWITCH_BLOCK_TX] = { .type = NLA_FLAG },
+ [NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX] = { .type = NLA_FLAG },
};
/* policy for the key attributes */
@@ -4811,7 +4814,8 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
struct cfg80211_chan_def chandef;
int err;
- if (!(rdev->wiphy.features & NL80211_FEATURE_20MHZ_DFS))
+ if (!(rdev->wiphy.features & NL80211_FEATURE_20MHZ_DFS) ||
+ !(rdev->wiphy.features & NL80211_FEATURE_AP_CH_SWITCH))
return -EOPNOTSUPP;
err = nl80211_parse_chandef(rdev, info, &chandef);
@@ -4853,6 +4857,51 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
return err;
}
+static int nl80211_ap_channel_switch(struct sk_buff *skb,
+ struct genl_info *info)
+{
+ struct cfg80211_registered_device *rdev = info->user_ptr[0];
+ struct net_device *dev = info->user_ptr[1];
+ struct ieee80211_ap_ch_switch ap_ch_sw;
+ int err;
+
+ if (!rdev->ops->ap_channel_switch)
+ return -EOPNOTSUPP;
+
+ if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP &&
+ dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO)
+ return -EOPNOTSUPP;
+
+ if (!info->attrs[NL80211_ATTR_CH_SWITCH_COUNT] ||
+ !info->attrs[NL80211_ATTR_WIPHY_FREQ] ||
+ !info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE])
+ return -EINVAL;
+
+ memset(&ap_ch_sw, 0, sizeof(ap_ch_sw));
+
+ err = nl80211_parse_chandef(rdev, info, &ap_ch_sw.chandef);
+ if (err)
+ return err;
+
+ /* DFS is currently supported for 20 MHz only. */
+ if (ap_ch_sw.chandef.width > NL80211_CHAN_WIDTH_20)
+ return -EOPNOTSUPP;
+
+ if (!ap_ch_sw.chandef.chan ||
+ ap_ch_sw.chandef.chan->flags & IEEE80211_CHAN_DISABLED)
+ return -EINVAL;
+
+ ap_ch_sw.count = nla_get_u32(info->attrs[NL80211_ATTR_CH_SWITCH_COUNT]);
+
+ if (info->attrs[NL80211_ATTR_CH_SWITCH_BLOCK_TX])
+ ap_ch_sw.block_tx = true;
+
+ if (info->attrs[NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX])
+ ap_ch_sw.post_switch_block_tx = true;
+
+ return rdev->ops->ap_channel_switch(&rdev->wiphy, dev, &ap_ch_sw);
+}
+
static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb,
u32 seq, int flags,
struct cfg80211_registered_device *rdev,
@@ -7844,6 +7893,14 @@ static struct genl_ops nl80211_ops[] = {
.internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
NL80211_FLAG_NEED_RTNL,
},
+ {
+ .cmd = NL80211_CMD_AP_CH_SWITCH,
+ .doit = nl80211_ap_channel_switch,
+ .policy = nl80211_policy,
+ .flags = GENL_ADMIN_PERM,
+ .internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
+ NL80211_FLAG_NEED_RTNL,
+ },
};
static struct genl_multicast_group nl80211_mlme_mcgrp = {
@@ -8958,7 +9015,8 @@ void nl80211_pmksa_candidate_notify(struct cfg80211_registered_device *rdev,
void nl80211_ch_switch_notify(struct cfg80211_registered_device *rdev,
struct net_device *netdev,
- struct cfg80211_chan_def *chandef, gfp_t gfp)
+ struct cfg80211_chan_def *chandef,
+ bool ap_stopped, gfp_t gfp)
{
struct sk_buff *msg;
void *hdr;
@@ -8979,6 +9037,11 @@ void nl80211_ch_switch_notify(struct cfg80211_registered_device *rdev,
if (nl80211_send_chandef(msg, chandef))
goto nla_put_failure;
+ if (ap_stopped &&
+ nla_put_flag(msg, NL80211_ATTR_CH_SWITCH_POST_BLOCK_TX))
+ goto nla_put_failure;
+
+
genlmsg_end(msg, hdr);
genlmsg_multicast_netns(wiphy_net(&rdev->wiphy), msg, 0,
diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index 28b9a34..68ac459 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -134,7 +134,8 @@ void nl80211_pmksa_candidate_notify(struct cfg80211_registered_device *rdev,
void nl80211_ch_switch_notify(struct cfg80211_registered_device *rdev,
struct net_device *dev,
- struct cfg80211_chan_def *chandef, gfp_t gfp);
+ struct cfg80211_chan_def *chandef,
+ bool ap_stopped, gfp_t gfp);
bool nl80211_unexpected_frame(struct net_device *dev,
const u8 *addr, gfp_t gfp);
--
1.7.10.4
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