From ee10f2c779b28c1d6e87ac3e1bbb1aa8b62fa891 Mon Sep 17 00:00:00 2001 From: Arik Nemtsov Date: Wed, 11 Jun 2014 17:18:27 +0300 Subject: [PATCH] mac80211: protect TDLS discovery session After sending a TDLS discovery-request, we expect a reply to arrive on the AP's channel. We must stay on the channel (no PSM, scan, etc.), since a TDLS setup-response is a direct packet not buffered by the AP. Add a new mac80211 driver callback to allow discovery session protection. Signed-off-by: Arik Nemtsov Reviewed-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- include/net/mac80211.h | 12 ++++++++++++ net/mac80211/driver-ops.h | 16 ++++++++++++++++ net/mac80211/tdls.c | 10 +++++++++- net/mac80211/trace.h | 7 +++++++ 4 files changed, 44 insertions(+), 1 deletion(-) diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 8d876dc8b299..18c2bdbaf988 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -2764,6 +2764,15 @@ enum ieee80211_roc_type { * mac80211 will transmit the frame right away. * The callback is optional and can (should!) sleep. * + * @mgd_protect_tdls_discover: Protect a TDLS discovery session. After sending + * a TDLS discovery-request, we expect a reply to arrive on the AP's + * channel. We must stay on the channel (no PSM, scan, etc.), since a TDLS + * setup-response is a direct packet not buffered by the AP. + * mac80211 will call this function just before the transmission of a TDLS + * discovery-request. The recommended period of protection is at least + * 2 * (DTIM period). + * The callback is optional and can sleep. + * * @add_chanctx: Notifies device driver about new channel context creation. * @remove_chanctx: Notifies device driver about channel context destruction. * @change_chanctx: Notifies device driver about channel context changes that @@ -2981,6 +2990,9 @@ struct ieee80211_ops { void (*mgd_prepare_tx)(struct ieee80211_hw *hw, struct ieee80211_vif *vif); + void (*mgd_protect_tdls_discover)(struct ieee80211_hw *hw, + struct ieee80211_vif *vif); + int (*add_chanctx)(struct ieee80211_hw *hw, struct ieee80211_chanctx_conf *ctx); void (*remove_chanctx)(struct ieee80211_hw *hw, diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h index bd782dcffcc7..2265bd7a44ba 100644 --- a/net/mac80211/driver-ops.h +++ b/net/mac80211/driver-ops.h @@ -970,6 +970,22 @@ static inline void drv_mgd_prepare_tx(struct ieee80211_local *local, trace_drv_return_void(local); } +static inline void +drv_mgd_protect_tdls_discover(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata) +{ + might_sleep(); + + if (!check_sdata_in_driver(sdata)) + return; + WARN_ON_ONCE(sdata->vif.type != NL80211_IFTYPE_STATION); + + trace_drv_mgd_protect_tdls_discover(local, sdata); + if (local->ops->mgd_protect_tdls_discover) + local->ops->mgd_protect_tdls_discover(&local->hw, &sdata->vif); + trace_drv_return_void(local); +} + static inline int drv_add_chanctx(struct ieee80211_local *local, struct ieee80211_chanctx *ctx) { diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c index b87e369561f4..f7185338a0fa 100644 --- a/net/mac80211/tdls.c +++ b/net/mac80211/tdls.c @@ -10,6 +10,7 @@ #include #include #include "ieee80211_i.h" +#include "driver-ops.h" /* give usermode some time for retries in setting up the TDLS session */ #define TDLS_PEER_SETUP_TIMEOUT (15 * HZ) @@ -442,8 +443,15 @@ int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev, peer_capability, initiator, extra_ies, extra_ies_len); break; - case WLAN_TDLS_SETUP_CONFIRM: case WLAN_TDLS_DISCOVERY_REQUEST: + /* + * Protect the discovery so we can hear the TDLS discovery + * response frame. It is transmitted directly and not buffered + * by the AP. + */ + drv_mgd_protect_tdls_discover(sdata->local, sdata); + /* fall-through */ + case WLAN_TDLS_SETUP_CONFIRM: case WLAN_PUB_ACTION_TDLS_DISCOVER_RES: /* no special handling */ ret = ieee80211_tdls_prep_mgmt_packet(wiphy, dev, peer, diff --git a/net/mac80211/trace.h b/net/mac80211/trace.h index cfe1a0688b5c..02ac535d1274 100644 --- a/net/mac80211/trace.h +++ b/net/mac80211/trace.h @@ -1330,6 +1330,13 @@ DEFINE_EVENT(local_sdata_evt, drv_mgd_prepare_tx, TP_ARGS(local, sdata) ); +DEFINE_EVENT(local_sdata_evt, drv_mgd_protect_tdls_discover, + TP_PROTO(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata), + + TP_ARGS(local, sdata) +); + DECLARE_EVENT_CLASS(local_chanctx, TP_PROTO(struct ieee80211_local *local, struct ieee80211_chanctx *ctx), -- 2.20.1