Return-path: Received: from ht2.myhostedexchange.com ([69.50.2.38]:18491 "EHLO ht1.hostedexchange.local" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752790Ab2LJKW7 (ORCPT ); Mon, 10 Dec 2012 05:22:59 -0500 From: Antonio Quartulli To: Johannes Berg CC: , Antonio Quartulli Subject: [PATCH] mac80211: in AD-HOC mode wait for the AUTH response Date: Mon, 10 Dec 2012 11:21:57 +0100 Message-ID: <1355134917-17705-2-git-send-email-antonio@open-mesh.com> (sfid-20121210_112310_084244_F28EA14D) In-Reply-To: <1355134917-17705-1-git-send-email-antonio@open-mesh.com> References: <1355134917-17705-1-git-send-email-antonio@open-mesh.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: To prevent race conditions between kernel state and user-space application knowledge, it is better to wait for a new peer to be completely authenticated before telling the userspace that it is ready to start authorization (IBSS/RSN). Use the IBSS_STA event to tell userspace when a station is authenticated and ready. It could still be the case that the other node joining the AD-HOC cell does not implement AUTH messages exchange, therefore a fallback mechanism will authenticate the peer after a timeout set for the purpose expires Signed-off-by: Antonio Quartulli --- net/mac80211/ibss.c | 97 ++++++++++++++++++++++++++++++++++++++++--------- net/mac80211/sta_info.h | 2 + 2 files changed, 81 insertions(+), 18 deletions(-) diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c index 700d0ed..9a11ec3 100644 --- a/net/mac80211/ibss.c +++ b/net/mac80211/ibss.c @@ -30,6 +30,7 @@ #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ) #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ) +#define IEEE80211_IBSS_AUTH_TIMEOUT (HZ / 2) #define IEEE80211_IBSS_MAX_STA_ENTRIES 128 @@ -273,8 +274,7 @@ static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, false); } -static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta, - bool auth) +static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta) __acquires(RCU) { struct ieee80211_sub_if_data *sdata = sta->sdata; @@ -284,19 +284,12 @@ static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta, ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr); - sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); - sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); - /* authorize the station only if the network is not RSN protected. If - * not wait for the userspace to authorize it */ - if (!sta->sdata->u.ibss.control_port) - sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); - rate_control_rate_init(sta); /* If it fails, maybe we raced another insertion? */ if (sta_info_insert_rcu(sta)) return sta_info_get(sdata, addr); - if (auth && !sdata->u.ibss.auth_frame_registrations) { + if (!sdata->u.ibss.auth_frame_registrations) { ibss_dbg(sdata, "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n", sdata->vif.addr, addr, sdata->u.ibss.bssid); @@ -309,7 +302,7 @@ static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta, static struct sta_info * ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid, const u8 *addr, - u32 supp_rates, bool auth) + u32 supp_rates) __acquires(RCU) { struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; @@ -358,7 +351,23 @@ ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, sta->sta.supp_rates[band] = supp_rates | ieee80211_mandatory_rates(local, band); - return ieee80211_ibss_finish_sta(sta, auth); + return ieee80211_ibss_finish_sta(sta); +} + +static void ieee80211_ibss_auth_sta(struct sta_info *sta) +{ + if (sta->sta_state > IEEE80211_STA_NONE) + return; + + sta_info_move_state(sta, IEEE80211_STA_AUTH); + sta_info_move_state(sta, IEEE80211_STA_ASSOC); + /* authorize the station only if the network is not RSN protected. If + * not wait for the userspace to authorize it + */ + if (!sta->sdata->u.ibss.control_port) + sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED); + + cfg80211_ibss_sta(sta->sdata->dev, sta->sta.addr, GFP_KERNEL); } static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata, @@ -395,13 +404,36 @@ static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n", mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction); - if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) + if (auth_alg != WLAN_AUTH_OPEN) return; - sta_info_destroy_addr(sdata, mgmt->sa); - sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false); + rcu_read_lock(); + sta = sta_info_get(sdata, mgmt->sa); rcu_read_unlock(); + if (auth_transaction == 2) { + ibss_dbg(sdata, "Authenticating STA %pM\n", sta->sta.addr); + ieee80211_ibss_auth_sta(sta); + return; + } + + /* drop bogus auth frames (auth_transaction can be only 1 or 2) */ + if (auth_transaction != 1) + return; + + if (sta && sdata->u.ibss.control_port && + sta->sta_state == IEEE80211_STA_AUTHORIZED) { + ibss_dbg(sdata, "Resetting STA %pM state for IBSS Encryption\n", + sta->sta.addr); + sta_info_destroy_addr(sdata, mgmt->sa); + sta = NULL; + } + + if (!sta) { + sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0); + rcu_read_unlock(); + } + /* * if we have any problem in allocating the new station, we reply with a * DEAUTH frame to tell the other end that we had a problem @@ -414,12 +446,16 @@ static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, return; } + sta->last_auth = jiffies; + /* * IEEE 802.11 standard does not require authentication in IBSS * networks and most implementations do not seem to use it. * However, try to reply to authentication attempts if someone * has actually implemented this. */ + ibss_dbg(sdata, "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=2)\n", + sdata->vif.addr, mgmt->sa, sdata->u.ibss.bssid); ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0, mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0); } @@ -481,7 +517,7 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, } else { rcu_read_unlock(); sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, - mgmt->sa, supp_rates, true); + mgmt->sa, supp_rates); } } @@ -592,7 +628,7 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, ieee80211_sta_join_ibss(sdata, bss); supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL); ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, - supp_rates, true); + supp_rates); rcu_read_unlock(); } @@ -675,6 +711,29 @@ static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) return active; } +static void ieee80211_ibss_auth_expire(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_local *local = sdata->local; + struct sta_info *sta; + + list_for_each_entry(sta, &local->sta_list, list) { + if (sdata != sta->sdata) + continue; + + if (sta->sta_state > IEEE80211_STA_NONE) + continue; + + if (time_after(jiffies, + sta->last_auth + IEEE80211_IBSS_AUTH_TIMEOUT)) { + ibss_dbg(sdata, + "Authenticating IBSS STA %pM by timeout\n", + sta->sta.addr); + ieee80211_ibss_auth_sta(sta); + } + } +} + + /* * This function is called with state == IEEE80211_IBSS_MLME_JOINED */ @@ -688,6 +747,8 @@ static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) mod_timer(&ifibss->timer, round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); + ieee80211_ibss_auth_expire(sdata); + ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); if (time_before(jiffies, ifibss->last_scan_completed + @@ -976,7 +1037,7 @@ void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) list_del(&sta->list); spin_unlock_bh(&ifibss->incomplete_lock); - ieee80211_ibss_finish_sta(sta, true); + ieee80211_ibss_finish_sta(sta); rcu_read_unlock(); spin_lock_bh(&ifibss->incomplete_lock); } diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h index 1489bca..3c150a4 100644 --- a/net/mac80211/sta_info.h +++ b/net/mac80211/sta_info.h @@ -244,6 +244,7 @@ struct sta_ampdu_mlme { * @rx_bytes: Number of bytes received from this STA * @wep_weak_iv_count: number of weak WEP IVs received from this station * @last_rx: time (in jiffies) when last frame was received from this STA + * @last_auth: jiffies of last auth packet with seq = 1 * @last_connected: time (in seconds) when a station got connected * @num_duplicates: number of duplicate frames received from this STA * @rx_fragments: number of received MPDUs @@ -324,6 +325,7 @@ struct sta_info { unsigned long rx_packets, rx_bytes; unsigned long wep_weak_iv_count; unsigned long last_rx; + unsigned long last_auth; long last_connected; unsigned long num_duplicates; unsigned long rx_fragments; -- 1.8.0