nl80211: enable IBSS support for channel switch announcements

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 34 insertions, 15 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index af8d84a4a5b2..ae617112b8f5 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5634,15 +5634,26 @@ 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));
 
@@ -5651,15 +5662,16 @@ 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;
@@ -5699,6 +5711,7 @@ 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;
@@ -5706,12 +5719,17 @@ 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,
@@ -10740,7 +10758,8 @@ 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;