nl80211: allow configuring IBSS beacon interval

Make the JOIN_IBSS command look at the beacon interval
attribute to see if the user requested a specific beacon
interval, if not default to 100 TU (wext too).

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 19 insertions, 2 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index dc9d9ec5d1ae..b6a48dd502ce 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -230,7 +230,9 @@
  *      and optionally a MAC (as BSSID) and FREQ_FIXED attribute if those
  *      should be fixed rather than automatically determined. Can only be
  *      executed on a network interface that is UP, and fixed BSSID/FREQ
- *      may be rejected.
+ *      may be rejected. Another optional parameter is the beacon interval,
+ *      given in the %NL80211_ATTR_BEACON_INTERVAL attribute, which if not
+ *      given defaults to 100 TU (102.4ms).
  * @NL80211_CMD_LEAVE_IBSS: Leave the IBSS -- no special arguments, the IBSS is
  *      determined by the network interface.
  *
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 54bc69c83691..7f7b53b69cb2 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -733,6 +733,7 @@ struct cfg80211_disassoc_request {
  *      IBSSs to join on other channels.
  * @ie: information element(s) to include in the beacon
  * @ie_len: length of that
+ * @beacon_interval: beacon interval to use
  */
 struct cfg80211_ibss_params {
         u8 *ssid;
@@ -740,6 +741,7 @@ struct cfg80211_ibss_params {
         struct ieee80211_channel *channel;
         u8 *ie;
         u8 ssid_len, ie_len;
+        u16 beacon_interval;
         bool channel_fixed;
 };
 
diff --git a/net/wireless/ibss.c b/net/wireless/ibss.c
index b5c601e1b1b7..3c38afaed28a 100644
--- a/net/wireless/ibss.c
+++ b/net/wireless/ibss.c
@@ -116,6 +116,9 @@ static int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
         enum ieee80211_band band;
         int i;
 
+        if (!wdev->wext.beacon_interval)
+                wdev->wext.beacon_interval = 100;
+
         /* try to find an IBSS channel if none requested ... */
         if (!wdev->wext.channel) {
                 for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 97bb5c80125d..3b21b3e89e96 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3159,6 +3159,8 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
         struct wiphy *wiphy;
         int err;
 
+        memset(&ibss, 0, sizeof(ibss));
+
         if (!is_valid_ie_attr(info->attrs[NL80211_ATTR_IE]))
                 return -EINVAL;
 
@@ -3167,6 +3169,15 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
             !nla_len(info->attrs[NL80211_ATTR_SSID]))
                 return -EINVAL;
 
+        ibss.beacon_interval = 100;
+
+        if (info->attrs[NL80211_ATTR_BEACON_INTERVAL]) {
+                ibss.beacon_interval =
+                        nla_get_u32(info->attrs[NL80211_ATTR_BEACON_INTERVAL]);
+                if (ibss.beacon_interval < 1 || ibss.beacon_interval > 10000)
+                        return -EINVAL;
+        }
+
         rtnl_lock();
 
         err = get_drv_dev_by_info_ifindex(info->attrs, &drv, &dev);
@@ -3189,7 +3200,6 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
         }
 
         wiphy = &drv->wiphy;
-        memset(&ibss, 0, sizeof(ibss));
 
         if (info->attrs[NL80211_ATTR_MAC])
                 ibss.bssid = nla_data(info->attrs[NL80211_ATTR_MAC]);