File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c
new file mode 100644
index 0000000..bd3d55e
--- /dev/null
+++ b/net/mac80211/mesh_plink.c
@@ -0,0 +1,1177 @@
+/*
+ * Copyright (c) 2008, 2009 open80211s Ltd.
+ * Author: Luis Carlos Cobo <luisca@cozybit.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/gfp.h>
+#include <linux/kernel.h>
+#include <linux/random.h>
+#include "ieee80211_i.h"
+#include "rate.h"
+#include "mesh.h"
+
+#define PLINK_CNF_AID(mgmt) ((mgmt)->u.action.u.self_prot.variable + 2)
+#define PLINK_GET_LLID(p) (p + 2)
+#define PLINK_GET_PLID(p) (p + 4)
+
+#define mod_plink_timer(s, t) (mod_timer(&s->mesh->plink_timer, \
+ jiffies + msecs_to_jiffies(t)))
+
+enum plink_event {
+ PLINK_UNDEFINED,
+ OPN_ACPT,
+ OPN_RJCT,
+ OPN_IGNR,
+ CNF_ACPT,
+ CNF_RJCT,
+ CNF_IGNR,
+ CLS_ACPT,
+ CLS_IGNR
+};
+
+static const char * const mplstates[] = {
+ [NL80211_PLINK_LISTEN] = "LISTEN",
+ [NL80211_PLINK_OPN_SNT] = "OPN-SNT",
+ [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD",
+ [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD",
+ [NL80211_PLINK_ESTAB] = "ESTAB",
+ [NL80211_PLINK_HOLDING] = "HOLDING",
+ [NL80211_PLINK_BLOCKED] = "BLOCKED"
+};
+
+static const char * const mplevents[] = {
+ [PLINK_UNDEFINED] = "NONE",
+ [OPN_ACPT] = "OPN_ACPT",
+ [OPN_RJCT] = "OPN_RJCT",
+ [OPN_IGNR] = "OPN_IGNR",
+ [CNF_ACPT] = "CNF_ACPT",
+ [CNF_RJCT] = "CNF_RJCT",
+ [CNF_IGNR] = "CNF_IGNR",
+ [CLS_ACPT] = "CLS_ACPT",
+ [CLS_IGNR] = "CLS_IGNR"
+};
+
+/* We only need a valid sta if user configured a minimum rssi_threshold. */
+static bool rssi_threshold_check(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta)
+{
+ s32 rssi_threshold = sdata->u.mesh.mshcfg.rssi_threshold;
+ return rssi_threshold == 0 ||
+ (sta &&
+ (s8)-ewma_signal_read(&sta->rx_stats.avg_signal) >
+ rssi_threshold);
+}
+
+/**
+ * mesh_plink_fsm_restart - restart a mesh peer link finite state machine
+ *
+ * @sta: mesh peer link to restart
+ *
+ * Locking: this function must be called holding sta->mesh->plink_lock
+ */
+static inline void mesh_plink_fsm_restart(struct sta_info *sta)
+{
+ lockdep_assert_held(&sta->mesh->plink_lock);
+ sta->mesh->plink_state = NL80211_PLINK_LISTEN;
+ sta->mesh->llid = sta->mesh->plid = sta->mesh->reason = 0;
+ sta->mesh->plink_retries = 0;
+}
+
+/*
+ * mesh_set_short_slot_time - enable / disable ERP short slot time.
+ *
+ * The standard indirectly mandates mesh STAs to turn off short slot time by
+ * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we
+ * can't be sneaky about it. Enable short slot time if all mesh STAs in the
+ * MBSS support ERP rates.
+ *
+ * Returns BSS_CHANGED_ERP_SLOT or 0 for no change.
+ */
+static u32 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_local *local = sdata->local;
+ enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
+ struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
+ struct sta_info *sta;
+ u32 erp_rates = 0, changed = 0;
+ int i;
+ bool short_slot = false;
+
+ if (band == IEEE80211_BAND_5GHZ) {
+ /* (IEEE 802.11-2012 19.4.5) */
+ short_slot = true;
+ goto out;
+ } else if (band != IEEE80211_BAND_2GHZ)
+ goto out;
+
+ for (i = 0; i < sband->n_bitrates; i++)
+ if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G)
+ erp_rates |= BIT(i);
+
+ if (!erp_rates)
+ goto out;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sta, &local->sta_list, list) {
+ if (sdata != sta->sdata ||
+ sta->mesh->plink_state != NL80211_PLINK_ESTAB)
+ continue;
+
+ short_slot = false;
+ if (erp_rates & sta->sta.supp_rates[band])
+ short_slot = true;
+ else
+ break;
+ }
+ rcu_read_unlock();
+
+out:
+ if (sdata->vif.bss_conf.use_short_slot != short_slot) {
+ sdata->vif.bss_conf.use_short_slot = short_slot;
+ changed = BSS_CHANGED_ERP_SLOT;
+ mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n",
+ sdata->vif.addr, short_slot);
+ }
+ return changed;
+}
+
+/**
+ * mesh_set_ht_prot_mode - set correct HT protection mode
+ *
+ * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT
+ * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT
+ * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is
+ * selected if any non-HT peers are present in our MBSS. 20MHz-protection mode
+ * is selected if all peers in our 20/40MHz MBSS support HT and atleast one
+ * HT20 peer is present. Otherwise no-protection mode is selected.
+ */
+static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct sta_info *sta;
+ u16 ht_opmode;
+ bool non_ht_sta = false, ht20_sta = false;
+
+ switch (sdata->vif.bss_conf.chandef.width) {
+ case NL80211_CHAN_WIDTH_20_NOHT:
+ case NL80211_CHAN_WIDTH_5:
+ case NL80211_CHAN_WIDTH_10:
+ return 0;
+ default:
+ break;
+ }
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sta, &local->sta_list, list) {
+ if (sdata != sta->sdata ||
+ sta->mesh->plink_state != NL80211_PLINK_ESTAB)
+ continue;
+
+ if (sta->sta.bandwidth > IEEE80211_STA_RX_BW_20)
+ continue;
+
+ if (!sta->sta.ht_cap.ht_supported) {
+ mpl_dbg(sdata, "nonHT sta (%pM) is present\n",
+ sta->sta.addr);
+ non_ht_sta = true;
+ break;
+ }
+
+ mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr);
+ ht20_sta = true;
+ }
+ rcu_read_unlock();
+
+ if (non_ht_sta)
+ ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED;
+ else if (ht20_sta &&
+ sdata->vif.bss_conf.chandef.width > NL80211_CHAN_WIDTH_20)
+ ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ;
+ else
+ ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE;
+
+ if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode)
+ return 0;
+
+ sdata->vif.bss_conf.ht_operation_mode = ht_opmode;
+ sdata->u.mesh.mshcfg.ht_opmode = ht_opmode;
+ mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode);
+ return BSS_CHANGED_HT;
+}
+
+static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta,
+ enum ieee80211_self_protected_actioncode action,
+ u8 *da, u16 llid, u16 plid, u16 reason)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct sk_buff *skb;
+ struct ieee80211_tx_info *info;
+ struct ieee80211_mgmt *mgmt;
+ bool include_plid = false;
+ u16 peering_proto = 0;
+ u8 *pos, ie_len = 4;
+ int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.self_prot) +
+ sizeof(mgmt->u.action.u.self_prot);
+ int err = -ENOMEM;
+
+ skb = dev_alloc_skb(local->tx_headroom +
+ hdr_len +
+ 2 + /* capability info */
+ 2 + /* AID */
+ 2 + 8 + /* supported rates */
+ 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
+ 2 + sdata->u.mesh.mesh_id_len +
+ 2 + sizeof(struct ieee80211_meshconf_ie) +
+ 2 + sizeof(struct ieee80211_ht_cap) +
+ 2 + sizeof(struct ieee80211_ht_operation) +
+ 2 + sizeof(struct ieee80211_vht_cap) +
+ 2 + sizeof(struct ieee80211_vht_operation) +
+ 2 + 8 + /* peering IE */
+ sdata->u.mesh.ie_len);
+ if (!skb)
+ return err;
+ info = IEEE80211_SKB_CB(skb);
+ skb_reserve(skb, local->tx_headroom);
+ mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
+ memset(mgmt, 0, hdr_len);
+ mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+ IEEE80211_STYPE_ACTION);
+ memcpy(mgmt->da, da, ETH_ALEN);
+ memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
+ memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
+ mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED;
+ mgmt->u.action.u.self_prot.action_code = action;
+
+ if (action != WLAN_SP_MESH_PEERING_CLOSE) {
+ enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
+
+ /* capability info */
+ pos = skb_put(skb, 2);
+ memset(pos, 0, 2);
+ if (action == WLAN_SP_MESH_PEERING_CONFIRM) {
+ /* AID */
+ pos = skb_put(skb, 2);
+ put_unaligned_le16(sta->sta.aid, pos);
+ }
+ if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
+ ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
+ mesh_add_rsn_ie(sdata, skb) ||
+ mesh_add_meshid_ie(sdata, skb) ||
+ mesh_add_meshconf_ie(sdata, skb))
+ goto free;
+ } else { /* WLAN_SP_MESH_PEERING_CLOSE */
+ info->flags |= IEEE80211_TX_CTL_NO_ACK;
+ if (mesh_add_meshid_ie(sdata, skb))
+ goto free;
+ }
+
+ /* Add Mesh Peering Management element */
+ switch (action) {
+ case WLAN_SP_MESH_PEERING_OPEN:
+ break;
+ case WLAN_SP_MESH_PEERING_CONFIRM:
+ ie_len += 2;
+ include_plid = true;
+ break;
+ case WLAN_SP_MESH_PEERING_CLOSE:
+ if (plid) {
+ ie_len += 2;
+ include_plid = true;
+ }
+ ie_len += 2; /* reason code */
+ break;
+ default:
+ err = -EINVAL;
+ goto free;
+ }
+
+ if (WARN_ON(skb_tailroom(skb) < 2 + ie_len))
+ goto free;
+
+ pos = skb_put(skb, 2 + ie_len);
+ *pos++ = WLAN_EID_PEER_MGMT;
+ *pos++ = ie_len;
+ memcpy(pos, &peering_proto, 2);
+ pos += 2;
+ put_unaligned_le16(llid, pos);
+ pos += 2;
+ if (include_plid) {
+ put_unaligned_le16(plid, pos);
+ pos += 2;
+ }
+ if (action == WLAN_SP_MESH_PEERING_CLOSE) {
+ put_unaligned_le16(reason, pos);
+ pos += 2;
+ }
+
+ if (action != WLAN_SP_MESH_PEERING_CLOSE) {
+ if (mesh_add_ht_cap_ie(sdata, skb) ||
+ mesh_add_ht_oper_ie(sdata, skb) ||
+ mesh_add_vht_cap_ie(sdata, skb) ||
+ mesh_add_vht_oper_ie(sdata, skb))
+ goto free;
+ }
+
+ if (mesh_add_vendor_ies(sdata, skb))
+ goto free;
+
+ ieee80211_tx_skb(sdata, skb);
+ return 0;
+free:
+ kfree_skb(skb);
+ return err;
+}
+
+/**
+ * __mesh_plink_deactivate - deactivate mesh peer link
+ *
+ * @sta: mesh peer link to deactivate
+ *
+ * All mesh paths with this peer as next hop will be flushed
+ * Returns beacon changed flag if the beacon content changed.
+ *
+ * Locking: the caller must hold sta->mesh->plink_lock
+ */
+static u32 __mesh_plink_deactivate(struct sta_info *sta)
+{
+ struct ieee80211_sub_if_data *sdata = sta->sdata;
+ u32 changed = 0;
+
+ lockdep_assert_held(&sta->mesh->plink_lock);
+
+ if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
+ changed = mesh_plink_dec_estab_count(sdata);
+ sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
+ mesh_path_flush_by_nexthop(sta);
+
+ ieee80211_mps_sta_status_update(sta);
+ changed |= ieee80211_mps_set_sta_local_pm(sta,
+ NL80211_MESH_POWER_UNKNOWN);
+
+ return changed;
+}
+
+/**
+ * mesh_plink_deactivate - deactivate mesh peer link
+ *
+ * @sta: mesh peer link to deactivate
+ *
+ * All mesh paths with this peer as next hop will be flushed
+ */
+u32 mesh_plink_deactivate(struct sta_info *sta)
+{
+ struct ieee80211_sub_if_data *sdata = sta->sdata;
+ u32 changed;
+
+ spin_lock_bh(&sta->mesh->plink_lock);
+ changed = __mesh_plink_deactivate(sta);
+ sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED;
+ mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE,
+ sta->sta.addr, sta->mesh->llid, sta->mesh->plid,
+ sta->mesh->reason);
+ spin_unlock_bh(&sta->mesh->plink_lock);
+
+ return changed;
+}
+
+static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta,
+ struct ieee802_11_elems *elems, bool insert)
+{
+ struct ieee80211_local *local = sdata->local;
+ enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
+ struct ieee80211_supported_band *sband;
+ u32 rates, basic_rates = 0, changed = 0;
+ enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
+
+ sband = local->hw.wiphy->bands[band];
+ rates = ieee80211_sta_get_rates(sdata, elems, band, &basic_rates);
+
+ spin_lock_bh(&sta->mesh->plink_lock);
+ sta->rx_stats.last_rx = jiffies;
+
+ /* rates and capabilities don't change during peering */
+ if (sta->mesh->plink_state == NL80211_PLINK_ESTAB &&
+ sta->mesh->processed_beacon)
+ goto out;
+ sta->mesh->processed_beacon = true;
+
+ if (sta->sta.supp_rates[band] != rates)
+ changed |= IEEE80211_RC_SUPP_RATES_CHANGED;
+ sta->sta.supp_rates[band] = rates;
+
+ if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
+ elems->ht_cap_elem, sta))
+ changed |= IEEE80211_RC_BW_CHANGED;
+
+ ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband,
+ elems->vht_cap_elem, sta);
+
+ if (bw != sta->sta.bandwidth)
+ changed |= IEEE80211_RC_BW_CHANGED;
+
+ /* HT peer is operating 20MHz-only */
+ if (elems->ht_operation &&
+ !(elems->ht_operation->ht_param &
+ IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) {
+ if (sta->sta.bandwidth != IEEE80211_STA_RX_BW_20)
+ changed |= IEEE80211_RC_BW_CHANGED;
+ sta->sta.bandwidth = IEEE80211_STA_RX_BW_20;
+ }
+
+ if (insert)
+ rate_control_rate_init(sta);
+ else
+ rate_control_rate_update(local, sband, sta, changed);
+out:
+ spin_unlock_bh(&sta->mesh->plink_lock);
+}
+
+static int mesh_allocate_aid(struct ieee80211_sub_if_data *sdata)
+{
+ struct sta_info *sta;
+ unsigned long *aid_map;
+ int aid;
+
+ aid_map = kcalloc(BITS_TO_LONGS(IEEE80211_MAX_AID + 1),
+ sizeof(*aid_map), GFP_KERNEL);
+ if (!aid_map)
+ return -ENOMEM;
+
+ /* reserve aid 0 for mcast indication */
+ __set_bit(0, aid_map);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sta, &sdata->local->sta_list, list)
+ __set_bit(sta->sta.aid, aid_map);
+ rcu_read_unlock();
+
+ aid = find_first_zero_bit(aid_map, IEEE80211_MAX_AID + 1);
+ kfree(aid_map);
+
+ if (aid > IEEE80211_MAX_AID)
+ return -ENOBUFS;
+
+ return aid;
+}
+
+static struct sta_info *
+__mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr)
+{
+ struct sta_info *sta;
+ int aid;
+
+ if (sdata->local->num_sta >= MESH_MAX_PLINKS)
+ return NULL;
+
+ aid = mesh_allocate_aid(sdata);
+ if (aid < 0)
+ return NULL;
+
+ sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL);
+ if (!sta)
+ return NULL;
+
+ sta->mesh->plink_state = NL80211_PLINK_LISTEN;
+ sta->sta.wme = true;
+ sta->sta.aid = aid;
+
+ sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
+ sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
+ sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
+
+ return sta;
+}
+
+static struct sta_info *
+mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
+ struct ieee802_11_elems *elems)
+{
+ struct sta_info *sta = NULL;
+
+ /* Userspace handles station allocation */
+ if (sdata->u.mesh.user_mpm ||
+ sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED)
+ cfg80211_notify_new_peer_candidate(sdata->dev, addr,
+ elems->ie_start,
+ elems->total_len,
+ GFP_KERNEL);
+ else
+ sta = __mesh_sta_info_alloc(sdata, addr);
+
+ return sta;
+}
+
+/*
+ * mesh_sta_info_get - return mesh sta info entry for @addr.
+ *
+ * @sdata: local meshif
+ * @addr: peer's address
+ * @elems: IEs from beacon or mesh peering frame.
+ *
+ * Return existing or newly allocated sta_info under RCU read lock.
+ * (re)initialize with given IEs.
+ */
+static struct sta_info *
+mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
+ u8 *addr, struct ieee802_11_elems *elems) __acquires(RCU)
+{
+ struct sta_info *sta = NULL;
+
+ rcu_read_lock();
+ sta = sta_info_get(sdata, addr);
+ if (sta) {
+ mesh_sta_info_init(sdata, sta, elems, false);
+ } else {
+ rcu_read_unlock();
+ /* can't run atomic */
+ sta = mesh_sta_info_alloc(sdata, addr, elems);
+ if (!sta) {
+ rcu_read_lock();
+ return NULL;
+ }
+
+ mesh_sta_info_init(sdata, sta, elems, true);
+
+ if (sta_info_insert_rcu(sta))
+ return NULL;
+ }
+
+ return sta;
+}
+
+/*
+ * mesh_neighbour_update - update or initialize new mesh neighbor.
+ *
+ * @sdata: local meshif
+ * @addr: peer's address
+ * @elems: IEs from beacon or mesh peering frame
+ *
+ * Initiates peering if appropriate.
+ */
+void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
+ u8 *hw_addr,
+ struct ieee802_11_elems *elems)
+{
+ struct sta_info *sta;
+ u32 changed = 0;
+
+ sta = mesh_sta_info_get(sdata, hw_addr, elems);
+ if (!sta)
+ goto out;
+
+ if (mesh_peer_accepts_plinks(elems) &&
+ sta->mesh->plink_state == NL80211_PLINK_LISTEN &&
+ sdata->u.mesh.accepting_plinks &&
+ sdata->u.mesh.mshcfg.auto_open_plinks &&
+ rssi_threshold_check(sdata, sta))
+ changed = mesh_plink_open(sta);
+
+ ieee80211_mps_frame_release(sta, elems);
+out:
+ rcu_read_unlock();
+ ieee80211_mbss_info_change_notify(sdata, changed);
+}
+
+static void mesh_plink_timer(unsigned long data)
+{
+ struct sta_info *sta;
+ u16 reason = 0;
+ struct ieee80211_sub_if_data *sdata;
+ struct mesh_config *mshcfg;
+ enum ieee80211_self_protected_actioncode action = 0;
+
+ /*
+ * This STA is valid because sta_info_destroy() will
+ * del_timer_sync() this timer after having made sure
+ * it cannot be readded (by deleting the plink.)
+ */
+ sta = (struct sta_info *) data;
+
+ if (sta->sdata->local->quiescing)
+ return;
+
+ spin_lock_bh(&sta->mesh->plink_lock);
+
+ /* If a timer fires just before a state transition on another CPU,
+ * we may have already extended the timeout and changed state by the
+ * time we've acquired the lock and arrived here. In that case,
+ * skip this timer and wait for the new one.
+ */
+ if (time_before(jiffies, sta->mesh->plink_timer.expires)) {
+ mpl_dbg(sta->sdata,
+ "Ignoring timer for %pM in state %s (timer adjusted)",
+ sta->sta.addr, mplstates[sta->mesh->plink_state]);
+ spin_unlock_bh(&sta->mesh->plink_lock);
+ return;
+ }
+
+ /* del_timer() and handler may race when entering these states */
+ if (sta->mesh->plink_state == NL80211_PLINK_LISTEN ||
+ sta->mesh->plink_state == NL80211_PLINK_ESTAB) {
+ mpl_dbg(sta->sdata,
+ "Ignoring timer for %pM in state %s (timer deleted)",
+ sta->sta.addr, mplstates[sta->mesh->plink_state]);
+ spin_unlock_bh(&sta->mesh->plink_lock);
+ return;
+ }
+
+ mpl_dbg(sta->sdata,
+ "Mesh plink timer for %pM fired on state %s\n",
+ sta->sta.addr, mplstates[sta->mesh->plink_state]);
+ sdata = sta->sdata;
+ mshcfg = &sdata->u.mesh.mshcfg;
+
+ switch (sta->mesh->plink_state) {
+ case NL80211_PLINK_OPN_RCVD:
+ case NL80211_PLINK_OPN_SNT:
+ /* retry timer */
+ if (sta->mesh->plink_retries < mshcfg->dot11MeshMaxRetries) {
+ u32 rand;
+ mpl_dbg(sta->sdata,
+ "Mesh plink for %pM (retry, timeout): %d %d\n",
+ sta->sta.addr, sta->mesh->plink_retries,
+ sta->mesh->plink_timeout);
+ get_random_bytes(&rand, sizeof(u32));
+ sta->mesh->plink_timeout = sta->mesh->plink_timeout +
+ rand % sta->mesh->plink_timeout;
+ ++sta->mesh->plink_retries;
+ mod_plink_timer(sta, sta->mesh->plink_timeout);
+ action = WLAN_SP_MESH_PEERING_OPEN;
+ break;
+ }
+ reason = WLAN_REASON_MESH_MAX_RETRIES;
+ /* fall through on else */
+ case NL80211_PLINK_CNF_RCVD:
+ /* confirm timer */
+ if (!reason)
+ reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT;
+ sta->mesh->plink_state = NL80211_PLINK_HOLDING;
+ mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
+ action = WLAN_SP_MESH_PEERING_CLOSE;
+ break;
+ case NL80211_PLINK_HOLDING:
+ /* holding timer */
+ del_timer(&sta->mesh->plink_timer);
+ mesh_plink_fsm_restart(sta);
+ break;
+ default:
+ break;
+ }
+ spin_unlock_bh(&sta->mesh->plink_lock);
+ if (action)
+ mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
+ sta->mesh->llid, sta->mesh->plid, reason);
+}
+
+static inline void mesh_plink_timer_set(struct sta_info *sta, u32 timeout)
+{
+ sta->mesh->plink_timer.expires = jiffies + msecs_to_jiffies(timeout);
+ sta->mesh->plink_timer.data = (unsigned long) sta;
+ sta->mesh->plink_timer.function = mesh_plink_timer;
+ sta->mesh->plink_timeout = timeout;
+ add_timer(&sta->mesh->plink_timer);
+}
+
+static bool llid_in_use(struct ieee80211_sub_if_data *sdata,
+ u16 llid)
+{
+ struct ieee80211_local *local = sdata->local;
+ bool in_use = false;
+ struct sta_info *sta;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sta, &local->sta_list, list) {
+ if (sdata != sta->sdata)
+ continue;
+
+ if (!memcmp(&sta->mesh->llid, &llid, sizeof(llid))) {
+ in_use = true;
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ return in_use;
+}
+
+static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata)
+{
+ u16 llid;
+
+ do {
+ get_random_bytes(&llid, sizeof(llid));
+ } while (llid_in_use(sdata, llid));
+
+ return llid;
+}
+
+u32 mesh_plink_open(struct sta_info *sta)
+{
+ struct ieee80211_sub_if_data *sdata = sta->sdata;
+ u32 changed;
+
+ if (!test_sta_flag(sta, WLAN_STA_AUTH))
+ return 0;
+
+ spin_lock_bh(&sta->mesh->plink_lock);
+ sta->mesh->llid = mesh_get_new_llid(sdata);
+ if (sta->mesh->plink_state != NL80211_PLINK_LISTEN &&
+ sta->mesh->plink_state != NL80211_PLINK_BLOCKED) {
+ spin_unlock_bh(&sta->mesh->plink_lock);
+ return 0;
+ }
+ sta->mesh->plink_state = NL80211_PLINK_OPN_SNT;
+ mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout);
+ spin_unlock_bh(&sta->mesh->plink_lock);
+ mpl_dbg(sdata,
+ "Mesh plink: starting establishment with %pM\n",
+ sta->sta.addr);
+
+ /* set the non-peer mode to active during peering */
+ changed = ieee80211_mps_local_status_update(sdata);
+
+ mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_OPEN,
+ sta->sta.addr, sta->mesh->llid, 0, 0);
+ return changed;
+}
+
+u32 mesh_plink_block(struct sta_info *sta)
+{
+ u32 changed;
+
+ spin_lock_bh(&sta->mesh->plink_lock);
+ changed = __mesh_plink_deactivate(sta);
+ sta->mesh->plink_state = NL80211_PLINK_BLOCKED;
+ spin_unlock_bh(&sta->mesh->plink_lock);
+
+ return changed;
+}
+
+static void mesh_plink_close(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta,
+ enum plink_event event)
+{
+ struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
+ u16 reason = (event == CLS_ACPT) ?
+ WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG;
+
+ sta->mesh->reason = reason;
+ sta->mesh->plink_state = NL80211_PLINK_HOLDING;
+ mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout);
+}
+
+static u32 mesh_plink_establish(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta)
+{
+ struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
+ u32 changed = 0;
+
+ del_timer(&sta->mesh->plink_timer);
+ sta->mesh->plink_state = NL80211_PLINK_ESTAB;
+ changed |= mesh_plink_inc_estab_count(sdata);
+ changed |= mesh_set_ht_prot_mode(sdata);
+ changed |= mesh_set_short_slot_time(sdata);
+ mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", sta->sta.addr);
+ ieee80211_mps_sta_status_update(sta);
+ changed |= ieee80211_mps_set_sta_local_pm(sta, mshcfg->power_mode);
+ return changed;
+}
+
+/**
+ * mesh_plink_fsm - step @sta MPM based on @event
+ *
+ * @sdata: interface
+ * @sta: mesh neighbor
+ * @event: peering event
+ *
+ * Return: changed MBSS flags
+ */
+static u32 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta, enum plink_event event)
+{
+ struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg;
+ enum ieee80211_self_protected_actioncode action = 0;
+ u32 changed = 0;
+
+ mpl_dbg(sdata, "peer %pM in state %s got event %s\n", sta->sta.addr,
+ mplstates[sta->mesh->plink_state], mplevents[event]);
+
+ spin_lock_bh(&sta->mesh->plink_lock);
+ switch (sta->mesh->plink_state) {
+ case NL80211_PLINK_LISTEN:
+ switch (event) {
+ case CLS_ACPT:
+ mesh_plink_fsm_restart(sta);
+ break;
+ case OPN_ACPT:
+ sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
+ sta->mesh->llid = mesh_get_new_llid(sdata);
+ mesh_plink_timer_set(sta,
+ mshcfg->dot11MeshRetryTimeout);
+
+ /* set the non-peer mode to active during peering */
+ changed |= ieee80211_mps_local_status_update(sdata);
+ action = WLAN_SP_MESH_PEERING_OPEN;
+ break;
+ default:
+ break;
+ }
+ break;
+ case NL80211_PLINK_OPN_SNT:
+ switch (event) {
+ case OPN_RJCT:
+ case CNF_RJCT:
+ case CLS_ACPT:
+ mesh_plink_close(sdata, sta, event);
+ action = WLAN_SP_MESH_PEERING_CLOSE;
+ break;
+ case OPN_ACPT:
+ /* retry timer is left untouched */
+ sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD;
+ action = WLAN_SP_MESH_PEERING_CONFIRM;
+ break;
+ case CNF_ACPT:
+ sta->mesh->plink_state = NL80211_PLINK_CNF_RCVD;
+ mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout);
+ break;
+ default:
+ break;
+ }
+ break;
+ case NL80211_PLINK_OPN_RCVD:
+ switch (event) {
+ case OPN_RJCT:
+ case CNF_RJCT:
+ case CLS_ACPT:
+ mesh_plink_close(sdata, sta, event);
+ action = WLAN_SP_MESH_PEERING_CLOSE;
+ break;
+ case OPN_ACPT:
+ action = WLAN_SP_MESH_PEERING_CONFIRM;
+ break;
+ case CNF_ACPT:
+ changed |= mesh_plink_establish(sdata, sta);
+ break;
+ default:
+ break;
+ }
+ break;
+ case NL80211_PLINK_CNF_RCVD:
+ switch (event) {
+ case OPN_RJCT:
+ case CNF_RJCT:
+ case CLS_ACPT:
+ mesh_plink_close(sdata, sta, event);
+ action = WLAN_SP_MESH_PEERING_CLOSE;
+ break;
+ case OPN_ACPT:
+ changed |= mesh_plink_establish(sdata, sta);
+ action = WLAN_SP_MESH_PEERING_CONFIRM;
+ break;
+ default:
+ break;
+ }
+ break;
+ case NL80211_PLINK_ESTAB:
+ switch (event) {
+ case CLS_ACPT:
+ changed |= __mesh_plink_deactivate(sta);
+ changed |= mesh_set_ht_prot_mode(sdata);
+ changed |= mesh_set_short_slot_time(sdata);
+ mesh_plink_close(sdata, sta, event);
+ action = WLAN_SP_MESH_PEERING_CLOSE;
+ break;
+ case OPN_ACPT:
+ action = WLAN_SP_MESH_PEERING_CONFIRM;
+ break;
+ default:
+ break;
+ }
+ break;
+ case NL80211_PLINK_HOLDING:
+ switch (event) {
+ case CLS_ACPT:
+ del_timer(&sta->mesh->plink_timer);
+ mesh_plink_fsm_restart(sta);
+ break;
+ case OPN_ACPT:
+ case CNF_ACPT:
+ case OPN_RJCT:
+ case CNF_RJCT:
+ action = WLAN_SP_MESH_PEERING_CLOSE;
+ break;
+ default:
+ break;
+ }
+ break;
+ default:
+ /* should not get here, PLINK_BLOCKED is dealt with at the
+ * beginning of the function
+ */
+ break;
+ }
+ spin_unlock_bh(&sta->mesh->plink_lock);
+ if (action) {
+ mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr,
+ sta->mesh->llid, sta->mesh->plid,
+ sta->mesh->reason);
+
+ /* also send confirm in open case */
+ if (action == WLAN_SP_MESH_PEERING_OPEN) {
+ mesh_plink_frame_tx(sdata, sta,
+ WLAN_SP_MESH_PEERING_CONFIRM,
+ sta->sta.addr, sta->mesh->llid,
+ sta->mesh->plid, 0);
+ }
+ }
+
+ return changed;
+}
+
+/*
+ * mesh_plink_get_event - get correct MPM event
+ *
+ * @sdata: interface
+ * @sta: peer, leave NULL if processing a frame from a new suitable peer
+ * @elems: peering management IEs
+ * @ftype: frame type
+ * @llid: peer's peer link ID
+ * @plid: peer's local link ID
+ *
+ * Return: new peering event for @sta, but PLINK_UNDEFINED should be treated as
+ * an error.
+ */
+static enum plink_event
+mesh_plink_get_event(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta,
+ struct ieee802_11_elems *elems,
+ enum ieee80211_self_protected_actioncode ftype,
+ u16 llid, u16 plid)
+{
+ enum plink_event event = PLINK_UNDEFINED;
+ u8 ie_len = elems->peering_len;
+ bool matches_local;
+
+ matches_local = (ftype == WLAN_SP_MESH_PEERING_CLOSE ||
+ mesh_matches_local(sdata, elems));
+
+ /* deny open request from non-matching peer */
+ if (!matches_local && !sta) {
+ event = OPN_RJCT;
+ goto out;
+ }
+
+ if (!sta) {
+ if (ftype != WLAN_SP_MESH_PEERING_OPEN) {
+ mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n");
+ goto out;
+ }
+ /* ftype == WLAN_SP_MESH_PEERING_OPEN */
+ if (!mesh_plink_free_count(sdata)) {
+ mpl_dbg(sdata, "Mesh plink error: no more free plinks\n");
+ goto out;
+ }
+ } else {
+ if (!test_sta_flag(sta, WLAN_STA_AUTH)) {
+ mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n");
+ goto out;
+ }
+ if (sta->mesh->plink_state == NL80211_PLINK_BLOCKED)
+ goto out;
+ }
+
+ /* new matching peer */
+ if (!sta) {
+ event = OPN_ACPT;
+ goto out;
+ }
+
+ switch (ftype) {
+ case WLAN_SP_MESH_PEERING_OPEN:
+ if (!matches_local)
+ event = OPN_RJCT;
+ if (!mesh_plink_free_count(sdata) ||
+ (sta->mesh->plid && sta->mesh->plid != plid))
+ event = OPN_IGNR;
+ else
+ event = OPN_ACPT;
+ break;
+ case WLAN_SP_MESH_PEERING_CONFIRM:
+ if (!matches_local)
+ event = CNF_RJCT;
+ if (!mesh_plink_free_count(sdata) ||
+ sta->mesh->llid != llid ||
+ (sta->mesh->plid && sta->mesh->plid != plid))
+ event = CNF_IGNR;
+ else
+ event = CNF_ACPT;
+ break;
+ case WLAN_SP_MESH_PEERING_CLOSE:
+ if (sta->mesh->plink_state == NL80211_PLINK_ESTAB)
+ /* Do not check for llid or plid. This does not
+ * follow the standard but since multiple plinks
+ * per sta are not supported, it is necessary in
+ * order to avoid a livelock when MP A sees an
+ * establish peer link to MP B but MP B does not
+ * see it. This can be caused by a timeout in
+ * B's peer link establishment or B beign
+ * restarted.
+ */
+ event = CLS_ACPT;
+ else if (sta->mesh->plid != plid)
+ event = CLS_IGNR;
+ else if (ie_len == 8 && sta->mesh->llid != llid)
+ event = CLS_IGNR;
+ else
+ event = CLS_ACPT;
+ break;
+ default:
+ mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n");
+ break;
+ }
+
+out:
+ return event;
+}
+
+static void
+mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt,
+ struct ieee802_11_elems *elems)
+{
+
+ struct sta_info *sta;
+ enum plink_event event;
+ enum ieee80211_self_protected_actioncode ftype;
+ u32 changed = 0;
+ u8 ie_len = elems->peering_len;
+ u16 plid, llid = 0;
+
+ if (!elems->peering) {
+ mpl_dbg(sdata,
+ "Mesh plink: missing necessary peer link ie\n");
+ return;
+ }
+
+ if (elems->rsn_len &&
+ sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) {
+ mpl_dbg(sdata,
+ "Mesh plink: can't establish link with secure peer\n");
+ return;
+ }
+
+ ftype = mgmt->u.action.u.self_prot.action_code;
+ if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) ||
+ (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) ||
+ (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6
+ && ie_len != 8)) {
+ mpl_dbg(sdata,
+ "Mesh plink: incorrect plink ie length %d %d\n",
+ ftype, ie_len);
+ return;
+ }
+
+ if (ftype != WLAN_SP_MESH_PEERING_CLOSE &&
+ (!elems->mesh_id || !elems->mesh_config)) {
+ mpl_dbg(sdata, "Mesh plink: missing necessary ie\n");
+ return;
+ }
+ /* Note the lines below are correct, the llid in the frame is the plid
+ * from the point of view of this host.
+ */
+ plid = get_unaligned_le16(PLINK_GET_LLID(elems->peering));
+ if (ftype == WLAN_SP_MESH_PEERING_CONFIRM ||
+ (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8))
+ llid = get_unaligned_le16(PLINK_GET_PLID(elems->peering));
+
+ /* WARNING: Only for sta pointer, is dropped & re-acquired */
+ rcu_read_lock();
+
+ sta = sta_info_get(sdata, mgmt->sa);
+
+ if (ftype == WLAN_SP_MESH_PEERING_OPEN &&
+ !rssi_threshold_check(sdata, sta)) {
+ mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n",
+ mgmt->sa);
+ goto unlock_rcu;
+ }
+
+ /* Now we will figure out the appropriate event... */
+ event = mesh_plink_get_event(sdata, sta, elems, ftype, llid, plid);
+
+ if (event == OPN_ACPT) {
+ rcu_read_unlock();
+ /* allocate sta entry if necessary and update info */
+ sta = mesh_sta_info_get(sdata, mgmt->sa, elems);
+ if (!sta) {
+ mpl_dbg(sdata, "Mesh plink: failed to init peer!\n");
+ goto unlock_rcu;
+ }
+ sta->mesh->plid = plid;
+ } else if (!sta && event == OPN_RJCT) {
+ mesh_plink_frame_tx(sdata, NULL, WLAN_SP_MESH_PEERING_CLOSE,
+ mgmt->sa, 0, plid,
+ WLAN_REASON_MESH_CONFIG);
+ goto unlock_rcu;
+ } else if (!sta || event == PLINK_UNDEFINED) {
+ /* something went wrong */
+ goto unlock_rcu;
+ }
+
+ if (event == CNF_ACPT) {
+ /* 802.11-2012 13.3.7.2 - update plid on CNF if not set */
+ if (!sta->mesh->plid)
+ sta->mesh->plid = plid;
+
+ sta->mesh->aid = get_unaligned_le16(PLINK_CNF_AID(mgmt));
+ }
+
+ changed |= mesh_plink_fsm(sdata, sta, event);
+
+unlock_rcu:
+ rcu_read_unlock();
+
+ if (changed)
+ ieee80211_mbss_info_change_notify(sdata, changed);
+}
+
+void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt, size_t len,
+ struct ieee80211_rx_status *rx_status)
+{
+ struct ieee802_11_elems elems;
+ size_t baselen;
+ u8 *baseaddr;
+
+ /* need action_code, aux */
+ if (len < IEEE80211_MIN_ACTION_SIZE + 3)
+ return;
+
+ if (sdata->u.mesh.user_mpm)
+ /* userspace must register for these */
+ return;
+
+ if (is_multicast_ether_addr(mgmt->da)) {
+ mpl_dbg(sdata,
+ "Mesh plink: ignore frame from multicast address\n");
+ return;
+ }
+
+ baseaddr = mgmt->u.action.u.self_prot.variable;
+ baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt;
+ if (mgmt->u.action.u.self_prot.action_code ==
+ WLAN_SP_MESH_PEERING_CONFIRM) {
+ baseaddr += 4;
+ baselen += 4;
+
+ if (baselen > len)
+ return;
+ }
+ ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems);
+ mesh_process_plink_frame(sdata, mgmt, &elems);
+}