mac80211: Drop DS Channel PARAM in directed probe

Do not send DS Channel parameter for directed probe requests
in order to maximize the chance that we get a response.  Some
badly-behaved APs don't respond when this parameter is included.

Signed-off-by: Paul Stewart <pstew@chromium.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 16 insertions, 5 deletions

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 05e3fb889d77..652e5695225a 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1018,7 +1018,8 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
 struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
                                           u8 *dst,
                                           const u8 *ssid, size_t ssid_len,
-                                          const u8 *ie, size_t ie_len)
+                                          const u8 *ie, size_t ie_len,
+                                          bool directed)
 {
         struct ieee80211_local *local = sdata->local;
         struct sk_buff *skb;
@@ -1035,8 +1036,16 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
                 return NULL;
         }
 
-        chan = ieee80211_frequency_to_channel(
-                local->hw.conf.channel->center_freq);
+        /*
+         * Do not send DS Channel parameter for directed probe requests
+         * in order to maximize the chance that we get a response.  Some
+         * badly-behaved APs don't respond when this parameter is included.
+         */
+        if (directed)
+                chan = 0;
+        else
+                chan = ieee80211_frequency_to_channel(
+                        local->hw.conf.channel->center_freq);
 
         buf_len = ieee80211_build_preq_ies(local, buf, ie, ie_len,
                                            local->hw.conf.channel->band,
@@ -1062,11 +1071,13 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 
 void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
                               const u8 *ssid, size_t ssid_len,
-                              const u8 *ie, size_t ie_len)
+                              const u8 *ie, size_t ie_len,
+                              bool directed)
 {
         struct sk_buff *skb;
 
-        skb = ieee80211_build_probe_req(sdata, dst, ssid, ssid_len, ie, ie_len);
+        skb = ieee80211_build_probe_req(sdata, dst, ssid, ssid_len, ie, ie_len,
+                                        directed);
         if (skb)
                 ieee80211_tx_skb(sdata, skb);
 }