Return-path: Received: from mail.fem.tu-ilmenau.de ([141.24.220.54]:34933 "EHLO mail.fem.tu-ilmenau.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751230AbcJEEzc (ORCPT ); Wed, 5 Oct 2016 00:55:32 -0400 From: Michael Braun To: johannes@sipsolutions.net Cc: Michael Braun , linux-wireless@vger.kernel.org, projekt-wlan@fem.tu-ilmenau.de Subject: [PATCH 2/3] mac80211: filter multicast data packets on AP / AP_VLAN Date: Wed, 5 Oct 2016 06:55:23 +0200 Message-Id: <1475643324-2845-2-git-send-email-michael-dev@fami-braun.de> (sfid-20161005_065535_491742_ABF92EFB) In-Reply-To: <1475643324-2845-1-git-send-email-michael-dev@fami-braun.de> References: <1475643324-2845-1-git-send-email-michael-dev@fami-braun.de> Sender: linux-wireless-owner@vger.kernel.org List-ID: This patch adds filtering for multicast data packets on AP_VLAN interfaces that have no authorized station connected and changes filtering on AP interfaces to not count stations assigned to AP_VLAN interfaces. This saves airtime and avoids waking up other stations currently authorized in this BSS. When using WPA, the packets dropped could not be decrypted by any station. The behaviour when there are no AP_VLAN interfaces is left unchanged. When there are AP_VLAN interfaces, this patch 1. adds filtering multicast data packets sent on AP_VLAN interfaces that have no authorized station connected. No filtering happens on 4addr AP_VLAN interfaces. 2. makes filtering of multicast data packets sent on AP interfaces depend on the number of authorized stations in this bss not assigned to an AP_VLAN interface. Therefore, two new num_mcast_sta like counters are added: one for the number of authorized stations connected to an AP_VLAN interface and one for the number of authorized stations connected to the bss and not assigned to any AP_VLAN. The already existing num_mcast_sta counter is left unchanged as it is used by SMPS. The new counters are exposed in debugfs. Signed-off-by: Michael Braun -- v3: - reuse existing num_mcast_sta v2: - use separate function to inc/dec mcast_sta counters - do not filter in 4addr mode - change description - change filtering on AP interface (do not count AP_VLAN sta) - use new counters regardless of 4addr or not - simplify cfg.c:change_station - remove no-op change in __cleanup_single_sta --- net/mac80211/cfg.c | 20 ++++++-------------- net/mac80211/debugfs_netdev.c | 11 +++++++++++ net/mac80211/ieee80211_i.h | 42 ++++++++++++++++++++++++++++++++++++++++++ net/mac80211/rx.c | 5 +++-- net/mac80211/sta_info.c | 10 ++-------- net/mac80211/tx.c | 5 ++--- 6 files changed, 66 insertions(+), 27 deletions(-) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 24133f5..1edb017 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1357,9 +1357,6 @@ static int ieee80211_change_station(struct wiphy *wiphy, goto out_err; if (params->vlan && params->vlan != sta->sdata->dev) { - bool prev_4addr = false; - bool new_4addr = false; - vlansdata = IEEE80211_DEV_TO_SUB_IF(params->vlan); if (params->vlan->ieee80211_ptr->use_4addr) { @@ -1369,26 +1366,21 @@ static int ieee80211_change_station(struct wiphy *wiphy, } rcu_assign_pointer(vlansdata->u.vlan.sta, sta); - new_4addr = true; __ieee80211_check_fast_rx_iface(vlansdata); } if (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && - sta->sdata->u.vlan.sta) { + sta->sdata->u.vlan.sta) RCU_INIT_POINTER(sta->sdata->u.vlan.sta, NULL); - prev_4addr = true; - } + + if (test_sta_flag(sta, WLAN_STA_AUTHORIZED)) + ieee80211_vif_dec_num_mcast(sta->sdata); sta->sdata = vlansdata; ieee80211_check_fast_xmit(sta); - if (sta->sta_state == IEEE80211_STA_AUTHORIZED && - prev_4addr != new_4addr) { - if (new_4addr) - atomic_dec(&sta->sdata->bss->num_mcast_sta); - else - atomic_inc(&sta->sdata->bss->num_mcast_sta); - } + if (test_sta_flag(sta, WLAN_STA_AUTHORIZED)) + ieee80211_vif_inc_num_mcast(sta->sdata); ieee80211_send_layer2_update(sta); } diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c index a5ba739..7fe468e 100644 --- a/net/mac80211/debugfs_netdev.c +++ b/net/mac80211/debugfs_netdev.c @@ -477,6 +477,7 @@ IEEE80211_IF_FILE_RW(tdls_wider_bw); IEEE80211_IF_FILE(num_mcast_sta, u.ap.num_mcast_sta, ATOMIC); IEEE80211_IF_FILE(num_sta_ps, u.ap.ps.num_sta_ps, ATOMIC); IEEE80211_IF_FILE(dtim_count, u.ap.ps.dtim_count, DEC); +IEEE80211_IF_FILE(num_mcast_sta_vlan, u.vlan.num_mcast_sta, ATOMIC); static ssize_t ieee80211_if_fmt_num_buffered_multicast( const struct ieee80211_sub_if_data *sdata, char *buf, int buflen) @@ -643,6 +644,13 @@ static void add_ap_files(struct ieee80211_sub_if_data *sdata) DEBUGFS_ADD_MODE(tkip_mic_test, 0200); } +static void add_vlan_files(struct ieee80211_sub_if_data *sdata) +{ + // add num_mcast_sta_vlan using name num_mcast_sta + debugfs_create_file("num_mcast_sta", 0400, sdata->vif.debugfs_dir, \ + sdata, &num_mcast_sta_vlan_ops); +} + static void add_ibss_files(struct ieee80211_sub_if_data *sdata) { DEBUGFS_ADD_MODE(tsf, 0600); @@ -746,6 +754,9 @@ static void add_files(struct ieee80211_sub_if_data *sdata) case NL80211_IFTYPE_AP: add_ap_files(sdata); break; + case NL80211_IFTYPE_AP_VLAN: + add_vlan_files(sdata); + break; case NL80211_IFTYPE_WDS: add_wds_files(sdata); break; diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index f56d342..933688e 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -305,6 +305,7 @@ struct ieee80211_if_vlan { /* used for all tx if the VLAN is configured to 4-addr mode */ struct sta_info __rcu *sta; + atomic_t num_mcast_sta; /* number of stations receiving multicast */ }; struct mesh_stats { @@ -1496,6 +1497,47 @@ ieee80211_have_rx_timestamp(struct ieee80211_rx_status *status) return false; } +static inline void +ieee80211_vif_inc_num_mcast(struct ieee80211_sub_if_data *sdata) +{ + if (sdata->vif.type != NL80211_IFTYPE_AP && + sdata->vif.type != NL80211_IFTYPE_AP_VLAN) + return; + + if (sdata->vif.type == NL80211_IFTYPE_AP) + atomic_inc(&sdata->u.ap.num_mcast_sta); + else if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) + atomic_inc(&sdata->u.vlan.num_mcast_sta); +} + +static inline void +ieee80211_vif_dec_num_mcast(struct ieee80211_sub_if_data *sdata) +{ + if (sdata->vif.type != NL80211_IFTYPE_AP && + sdata->vif.type != NL80211_IFTYPE_AP_VLAN) + return; + + if (sdata->vif.type == NL80211_IFTYPE_AP) + atomic_dec(&sdata->u.ap.num_mcast_sta); + else if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) + atomic_dec(&sdata->u.vlan.num_mcast_sta); +} + +/* This function returns the number of multicast stations connected to this + * interface. It returns -1 if that number is not tracked, that is for netdevs + * not in AP or AP_VLAN mode or when using 4addr. */ +static inline int +ieee80211_vif_get_num_mcast_if(struct ieee80211_sub_if_data *sdata) +{ + if (sdata->vif.type == NL80211_IFTYPE_AP) + return atomic_read(&sdata->u.ap.num_mcast_sta); + else if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN && + !sdata->u.vlan.sta) + return atomic_read(&sdata->u.vlan.num_mcast_sta); + else + return -1; +} + u64 ieee80211_calculate_rx_timestamp(struct ieee80211_local *local, struct ieee80211_rx_status *status, unsigned int mpdu_len, diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index fbf99b8..9c5d222 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -2161,7 +2161,8 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx) sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && (sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) { - if (is_multicast_ether_addr(ehdr->h_dest)) { + if (is_multicast_ether_addr(ehdr->h_dest) && + ieee80211_vif_get_num_mcast_if(sdata) != 0) { /* * send multicast frames both to higher layers in * local net stack and back to the wireless medium @@ -2170,7 +2171,7 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx) if (!xmit_skb) net_info_ratelimited("%s: failed to clone multicast frame\n", dev->name); - } else { + } else if (!is_multicast_ether_addr(ehdr->h_dest)) { dsta = sta_info_get(sdata, skb->data); if (dsta) { /* diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 76b737d..216ef65 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -1882,10 +1882,7 @@ int sta_info_move_state(struct sta_info *sta, if (!sta->sta.support_p2p_ps) ieee80211_recalc_p2p_go_ps_allowed(sta->sdata); } else if (sta->sta_state == IEEE80211_STA_AUTHORIZED) { - if (sta->sdata->vif.type == NL80211_IFTYPE_AP || - (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && - !sta->sdata->u.vlan.sta)) - atomic_dec(&sta->sdata->bss->num_mcast_sta); + ieee80211_vif_dec_num_mcast(sta->sdata); clear_bit(WLAN_STA_AUTHORIZED, &sta->_flags); ieee80211_clear_fast_xmit(sta); ieee80211_clear_fast_rx(sta); @@ -1893,10 +1890,7 @@ int sta_info_move_state(struct sta_info *sta, break; case IEEE80211_STA_AUTHORIZED: if (sta->sta_state == IEEE80211_STA_ASSOC) { - if (sta->sdata->vif.type == NL80211_IFTYPE_AP || - (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && - !sta->sdata->u.vlan.sta)) - atomic_inc(&sta->sdata->bss->num_mcast_sta); + ieee80211_vif_inc_num_mcast(sta->sdata); set_bit(WLAN_STA_AUTHORIZED, &sta->_flags); ieee80211_check_fast_xmit(sta); ieee80211_check_fast_rx(sta); diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 5023966..aed375f 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -331,9 +331,8 @@ ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx) I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc); return TX_DROP; } - } else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP && - ieee80211_is_data(hdr->frame_control) && - !atomic_read(&tx->sdata->u.ap.num_mcast_sta))) { + } else if (unlikely(ieee80211_vif_get_num_mcast_if(tx->sdata) == 0 && + ieee80211_is_data(hdr->frame_control))) { /* * No associated STAs - no need to send multicast * frames. -- 2.1.4