mac80211: support HT for TDLS stations

Add the HT capabilities and HT operation information elements to TDLS
setup packets where appropriate.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

2 files changed, 87 insertions, 8 deletions

diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c
index 15702ff64a4c..568055c02a98 100644
--- a/net/mac80211/ht.c
+++ b/net/mac80211/ht.c
@@ -150,13 +150,12 @@ bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
 
         /*
          * If user has specified capability over-rides, take care
-         * of that if the station we're setting up is the AP that
+         * of that if the station we're setting up is the AP or TDLS peer that
          * we advertised a restricted capability set to. Override
          * our own capabilities and then use those below.
          */
-        if ((sdata->vif.type == NL80211_IFTYPE_STATION ||
-             sdata->vif.type == NL80211_IFTYPE_ADHOC) &&
-            !test_sta_flag(sta, WLAN_STA_TDLS_PEER))
+        if (sdata->vif.type == NL80211_IFTYPE_STATION ||
+            sdata->vif.type == NL80211_IFTYPE_ADHOC)
                 ieee80211_apply_htcap_overrides(sdata, &own_cap);
 
         /*
diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c
index c59b8f460eb9..50d0e0660cc4 100644
--- a/net/mac80211/tdls.c
+++ b/net/mac80211/tdls.c
@@ -170,9 +170,23 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 {
         enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
         struct ieee80211_local *local = sdata->local;
+        struct ieee80211_supported_band *sband;
+        struct ieee80211_sta_ht_cap ht_cap;
+        struct sta_info *sta = NULL;
         size_t offset = 0, noffset;
         u8 *pos;
 
+        rcu_read_lock();
+
+        /* we should have the peer STA if we're already responding */
+        if (action_code == WLAN_TDLS_SETUP_RESPONSE) {
+                sta = sta_info_get(sdata, peer);
+                if (WARN_ON_ONCE(!sta)) {
+                        rcu_read_unlock();
+                        return;
+                }
+        }
+
         ieee80211_add_srates_ie(sdata, skb, false, band);
         ieee80211_add_ext_srates_ie(sdata, skb, false, band);
 
@@ -224,6 +238,38 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
                 offset = noffset;
         }
 
+        /*
+         * with TDLS we can switch channels, and HT-caps are not necessarily
+         * the same on all bands. The specification limits the setup to a
+         * single HT-cap, so use the current band for now.
+         */
+        sband = local->hw.wiphy->bands[band];
+        memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
+        if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
+             action_code == WLAN_TDLS_SETUP_RESPONSE) &&
+            ht_cap.ht_supported && (!sta || sta->sta.ht_cap.ht_supported)) {
+                if (action_code == WLAN_TDLS_SETUP_REQUEST) {
+                        ieee80211_apply_htcap_overrides(sdata, &ht_cap);
+
+                        /* disable SMPS in TDLS initiator */
+                        ht_cap.cap |= (WLAN_HT_CAP_SM_PS_DISABLED
+                                       << IEEE80211_HT_CAP_SM_PS_SHIFT);
+                } else {
+                        /* disable SMPS in TDLS responder */
+                        sta->sta.ht_cap.cap |=
+                                (WLAN_HT_CAP_SM_PS_DISABLED
+                                 << IEEE80211_HT_CAP_SM_PS_SHIFT);
+
+                        /* the peer caps are already intersected with our own */
+                        memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
+                }
+
+                pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
+                ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
+        }
+
+        rcu_read_unlock();
+
         /* add any remaining IEs */
         if (extra_ies_len) {
                 noffset = extra_ies_len;
@@ -241,14 +287,16 @@ ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
                                  size_t extra_ies_len)
 {
         struct ieee80211_local *local = sdata->local;
+        struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
         size_t offset = 0, noffset;
-        struct sta_info *sta;
+        struct sta_info *sta, *ap_sta;
         u8 *pos;
 
         rcu_read_lock();
 
         sta = sta_info_get(sdata, peer);
-        if (WARN_ON_ONCE(!sta)) {
+        ap_sta = sta_info_get(sdata, ifmgd->bssid);
+        if (WARN_ON_ONCE(!sta || !ap_sta)) {
                 rcu_read_unlock();
                 return;
         }
@@ -272,6 +320,38 @@ ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
             test_sta_flag(sta, WLAN_STA_WME))
                 ieee80211_tdls_add_wmm_param_ie(sdata, skb);
 
+        /* add any custom IEs that go before HT operation */
+        if (extra_ies_len) {
+                static const u8 before_ht_op[] = {
+                        WLAN_EID_RSN,
+                        WLAN_EID_QOS_CAPA,
+                        WLAN_EID_FAST_BSS_TRANSITION,
+                        WLAN_EID_TIMEOUT_INTERVAL,
+                };
+                noffset = ieee80211_ie_split(extra_ies, extra_ies_len,
+                                             before_ht_op,
+                                             ARRAY_SIZE(before_ht_op),
+                                             offset);
+                pos = skb_put(skb, noffset - offset);
+                memcpy(pos, extra_ies + offset, noffset - offset);
+                offset = noffset;
+        }
+
+        /* if HT support is only added in TDLS, we need an HT-operation IE */
+        if (!ap_sta->sta.ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
+                struct ieee80211_chanctx_conf *chanctx_conf =
+                                rcu_dereference(sdata->vif.chanctx_conf);
+                if (!WARN_ON(!chanctx_conf)) {
+                        pos = skb_put(skb, 2 +
+                                      sizeof(struct ieee80211_ht_operation));
+                        /* send an empty HT operation IE */
+                        ieee80211_ie_build_ht_oper(pos, &sta->sta.ht_cap,
+                                                   &chanctx_conf->def, 0);
+                }
+        }
+
+        rcu_read_unlock();
+
         /* add any remaining IEs */
         if (extra_ies_len) {
                 noffset = extra_ies_len;
@@ -280,8 +360,6 @@ ieee80211_tdls_add_setup_cfm_ies(struct ieee80211_sub_if_data *sdata,
         }
 
         ieee80211_tdls_add_link_ie(sdata, skb, peer, initiator);
-
-        rcu_read_unlock();
 }
 
 static void ieee80211_tdls_add_ies(struct ieee80211_sub_if_data *sdata,
@@ -441,6 +519,8 @@ ieee80211_tdls_prep_mgmt_packet(struct wiphy *wiphy, struct net_device *dev,
                             50 + /* supported rates */
                             7 + /* ext capab */
                             26 + /* max(WMM-info, WMM-param) */
+                            2 + max(sizeof(struct ieee80211_ht_cap),
+                                    sizeof(struct ieee80211_ht_operation)) +
                             extra_ies_len +
                             sizeof(struct ieee80211_tdls_lnkie));
         if (!skb)