/* * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005-2006, Devicescape Software, Inc. * Copyright 2006-2007 Jiri Benc * Copyright 2007 Johannes Berg * * 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. * * utilities for mac80211 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "ieee80211_i.h" #include "driver-ops.h" #include "rate.h" #include "mesh.h" #include "wme.h" #include "led.h" #include "wep.h" /* privid for wiphys to determine whether they belong to us or not */ void *mac80211_wiphy_privid = &mac80211_wiphy_privid; struct ieee80211_hw *wiphy_to_ieee80211_hw(struct wiphy *wiphy) { struct ieee80211_local *local; BUG_ON(!wiphy); local = wiphy_priv(wiphy); return &local->hw; } EXPORT_SYMBOL(wiphy_to_ieee80211_hw); u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len, enum nl80211_iftype type) { __le16 fc = hdr->frame_control; /* drop ACK/CTS frames and incorrect hdr len (ctrl) */ if (len < 16) return NULL; if (ieee80211_is_data(fc)) { if (len < 24) /* drop incorrect hdr len (data) */ return NULL; if (ieee80211_has_a4(fc)) return NULL; if (ieee80211_has_tods(fc)) return hdr->addr1; if (ieee80211_has_fromds(fc)) return hdr->addr2; return hdr->addr3; } if (ieee80211_is_mgmt(fc)) { if (len < 24) /* drop incorrect hdr len (mgmt) */ return NULL; return hdr->addr3; } if (ieee80211_is_ctl(fc)) { if(ieee80211_is_pspoll(fc)) return hdr->addr1; if (ieee80211_is_back_req(fc)) { switch (type) { case NL80211_IFTYPE_STATION: return hdr->addr2; case NL80211_IFTYPE_AP: case NL80211_IFTYPE_AP_VLAN: return hdr->addr1; default: break; /* fall through to the return */ } } } return NULL; } void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx) { struct sk_buff *skb; struct ieee80211_hdr *hdr; skb_queue_walk(&tx->skbs, skb) { hdr = (struct ieee80211_hdr *) skb->data; hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); } } int ieee80211_frame_duration(struct ieee80211_local *local, size_t len, int rate, int erp, int short_preamble) { int dur; /* calculate duration (in microseconds, rounded up to next higher * integer if it includes a fractional microsecond) to send frame of * len bytes (does not include FCS) at the given rate. Duration will * also include SIFS. * * rate is in 100 kbps, so divident is multiplied by 10 in the * DIV_ROUND_UP() operations. */ if (local->hw.conf.channel->band == IEEE80211_BAND_5GHZ || erp) { /* * OFDM: * * N_DBPS = DATARATE x 4 * N_SYM = Ceiling((16+8xLENGTH+6) / N_DBPS) * (16 = SIGNAL time, 6 = tail bits) * TXTIME = T_PREAMBLE + T_SIGNAL + T_SYM x N_SYM + Signal Ext * * T_SYM = 4 usec * 802.11a - 17.5.2: aSIFSTime = 16 usec * 802.11g - 19.8.4: aSIFSTime = 10 usec + * signal ext = 6 usec */ dur = 16; /* SIFS + signal ext */ dur += 16; /* 17.3.2.3: T_PREAMBLE = 16 usec */ dur += 4; /* 17.3.2.3: T_SIGNAL = 4 usec */ dur += 4 * DIV_ROUND_UP((16 + 8 * (len + 4) + 6) * 10, 4 * rate); /* T_SYM x N_SYM */ } else { /* * 802.11b or 802.11g with 802.11b compatibility: * 18.3.4: TXTIME = PreambleLength + PLCPHeaderTime + * Ceiling(((LENGTH+PBCC)x8)/DATARATE). PBCC=0. * * 802.11 (DS): 15.3.3, 802.11b: 18.3.4 * aSIFSTime = 10 usec * aPreambleLength = 144 usec or 72 usec with short preamble * aPLCPHeaderLength = 48 usec or 24 usec with short preamble */ dur = 10; /* aSIFSTime = 10 usec */ dur += short_preamble ? (72 + 24) : (144 + 48); dur += DIV_ROUND_UP(8 * (len + 4) * 10, rate); } return dur; } /* Exported duration function for driver use */ __le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw, struct ieee80211_vif *vif, size_t frame_len, struct ieee80211_rate *rate) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_sub_if_data *sdata; u16 dur; int erp; bool short_preamble = false; erp = 0; if (vif) { sdata = vif_to_sdata(vif); short_preamble = sdata->vif.bss_conf.use_short_preamble; if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) erp = rate->flags & IEEE80211_RATE_ERP_G; } dur = ieee80211_frame_duration(local, frame_len, rate->bitrate, erp, short_preamble); return cpu_to_le16(dur); } EXPORT_SYMBOL(ieee80211_generic_frame_duration); __le16 ieee80211_rts_duration(struct ieee80211_hw *hw, struct ieee80211_vif *vif, size_t frame_len, const struct ieee80211_tx_info *frame_txctl) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_rate *rate; struct ieee80211_sub_if_data *sdata; bool short_preamble; int erp; u16 dur; struct ieee80211_supported_band *sband; sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; short_preamble = false; rate = &sband->bitrates[frame_txctl->control.rts_cts_rate_idx]; erp = 0; if (vif) { sdata = vif_to_sdata(vif); short_preamble = sdata->vif.bss_conf.use_short_preamble; if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) erp = rate->flags & IEEE80211_RATE_ERP_G; } /* CTS duration */ dur = ieee80211_frame_duration(local, 10, rate->bitrate, erp, short_preamble); /* Data frame duration */ dur += ieee80211_frame_duration(local, frame_len, rate->bitrate, erp, short_preamble); /* ACK duration */ dur += ieee80211_frame_duration(local, 10, rate->bitrate, erp, short_preamble); return cpu_to_le16(dur); } EXPORT_SYMBOL(ieee80211_rts_duration); __le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw, struct ieee80211_vif *vif, size_t frame_len, const struct ieee80211_tx_info *frame_txctl) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_rate *rate; struct ieee80211_sub_if_data *sdata; bool short_preamble; int erp; u16 dur; struct ieee80211_supported_band *sband; sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; short_preamble = false; rate = &sband->bitrates[frame_txctl->control.rts_cts_rate_idx]; erp = 0; if (vif) { sdata = vif_to_sdata(vif); short_preamble = sdata->vif.bss_conf.use_short_preamble; if (sdata->flags & IEEE80211_SDATA_OPERATING_GMODE) erp = rate->flags & IEEE80211_RATE_ERP_G; } /* Data frame duration */ dur = ieee80211_frame_duration(local, frame_len, rate->bitrate, erp, short_preamble); if (!(frame_txctl->flags & IEEE80211_TX_CTL_NO_ACK)) { /* ACK duration */ dur += ieee80211_frame_duration(local, 10, rate->bitrate, erp, short_preamble); } return cpu_to_le16(dur); } EXPORT_SYMBOL(ieee80211_ctstoself_duration); static void __ieee80211_wake_queue(struct ieee80211_hw *hw, int queue, enum queue_stop_reason reason) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_sub_if_data *sdata; trace_wake_queue(local, queue, reason); if (WARN_ON(queue >= hw->queues)) return; __clear_bit(reason, &local->queue_stop_reasons[queue]); if (local->queue_stop_reasons[queue] != 0) /* someone still has this queue stopped */ return; if (skb_queue_empty(&local->pending[queue])) { rcu_read_lock(); list_for_each_entry_rcu(sdata, &local->interfaces, list) { if (test_bit(SDATA_STATE_OFFCHANNEL, &sdata->state)) continue; netif_wake_subqueue(sdata->dev, queue); } rcu_read_unlock(); } else tasklet_schedule(&local->tx_pending_tasklet); } void ieee80211_wake_queue_by_reason(struct ieee80211_hw *hw, int queue, enum queue_stop_reason reason) { struct ieee80211_local *local = hw_to_local(hw); unsigned long flags; spin_lock_irqsave(&local->queue_stop_reason_lock, flags); __ieee80211_wake_queue(hw, queue, reason); spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); } void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue) { ieee80211_wake_queue_by_reason(hw, queue, IEEE80211_QUEUE_STOP_REASON_DRIVER); } EXPORT_SYMBOL(ieee80211_wake_queue); static void __ieee80211_stop_queue(struct ieee80211_hw *hw, int queue, enum queue_stop_reason reason) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_sub_if_data *sdata; trace_stop_queue(local, queue, reason); if (WARN_ON(queue >= hw->queues)) return; __set_bit(reason, &local->queue_stop_reasons[queue]); rcu_read_lock(); list_for_each_entry_rcu(sdata, &local->interfaces, list) netif_stop_subqueue(sdata->dev, queue); rcu_read_unlock(); } void ieee80211_stop_queue_by_reason(struct ieee80211_hw *hw, int queue, enum queue_stop_reason reason) { struct ieee80211_local *local = hw_to_local(hw); unsigned long flags; spin_lock_irqsave(&local->queue_stop_reason_lock, flags); __ieee80211_stop_queue(hw, queue, reason); spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); } void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue) { ieee80211_stop_queue_by_reason(hw, queue, IEEE80211_QUEUE_STOP_REASON_DRIVER); } EXPORT_SYMBOL(ieee80211_stop_queue); void ieee80211_add_pending_skb(struct ieee80211_local *local, struct sk_buff *skb) { struct ieee80211_hw *hw = &local->hw; unsigned long flags; int queue = skb_get_queue_mapping(skb); struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); if (WARN_ON(!info->control.vif)) { kfree_skb(skb); return; } spin_lock_irqsave(&local->queue_stop_reason_lock, flags); __ieee80211_stop_queue(hw, queue, IEEE80211_QUEUE_STOP_REASON_SKB_ADD); __skb_queue_tail(&local->pending[queue], skb); __ieee80211_wake_queue(hw, queue, IEEE80211_QUEUE_STOP_REASON_SKB_ADD); spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); } void ieee80211_add_pending_skbs_fn(struct ieee80211_local *local, struct sk_buff_head *skbs, void (*fn)(void *data), void *data) { struct ieee80211_hw *hw = &local->hw; struct sk_buff *skb; unsigned long flags; int queue, i; spin_lock_irqsave(&local->queue_stop_reason_lock, flags); for (i = 0; i < hw->queues; i++) __ieee80211_stop_queue(hw, i, IEEE80211_QUEUE_STOP_REASON_SKB_ADD); while ((skb = skb_dequeue(skbs))) { struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); if (WARN_ON(!info->control.vif)) { kfree_skb(skb); continue; } queue = skb_get_queue_mapping(skb); __skb_queue_tail(&local->pending[queue], skb); } if (fn) fn(data); for (i = 0; i < hw->queues; i++) __ieee80211_wake_queue(hw, i, IEEE80211_QUEUE_STOP_REASON_SKB_ADD); spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); } void ieee80211_add_pending_skbs(struct ieee80211_local *local, struct sk_buff_head *skbs) { ieee80211_add_pending_skbs_fn(local, skbs, NULL, NULL); } void ieee80211_stop_queues_by_reason(struct ieee80211_hw *hw, enum queue_stop_reason reason) { struct ieee80211_local *local = hw_to_local(hw); unsigned long flags; int i; spin_lock_irqsave(&local->queue_stop_reason_lock, flags); for (i = 0; i < hw->queues; i++) __ieee80211_stop_queue(hw, i, reason); spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); } void ieee80211_stop_queues(struct ieee80211_hw *hw) { ieee80211_stop_queues_by_reason(hw, IEEE80211_QUEUE_STOP_REASON_DRIVER); } EXPORT_SYMBOL(ieee80211_stop_queues); int ieee80211_queue_stopped(struct ieee80211_hw *hw, int queue) { struct ieee80211_local *local = hw_to_local(hw); unsigned long flags; int ret; if (WARN_ON(queue >= hw->queues)) return true; spin_lock_irqsave(&local->queue_stop_reason_lock, flags); ret = !!local->queue_stop_reasons[queue]; spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); return ret; } EXPORT_SYMBOL(ieee80211_queue_stopped); void ieee80211_wake_queues_by_reason(struct ieee80211_hw *hw, enum queue_stop_reason reason) { struct ieee80211_local *local = hw_to_local(hw); unsigned long flags; int i; spin_lock_irqsave(&local->queue_stop_reason_lock, flags); for (i = 0; i < hw->queues; i++) __ieee80211_wake_queue(hw, i, reason); spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); } void ieee80211_wake_queues(struct ieee80211_hw *hw) { ieee80211_wake_queues_by_reason(hw, IEEE80211_QUEUE_STOP_REASON_DRIVER); } EXPORT_SYMBOL(ieee80211_wake_queues); void ieee80211_iterate_active_interfaces( struct ieee80211_hw *hw, void (*iterator)(void *data, u8 *mac, struct ieee80211_vif *vif), void *data) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_sub_if_data *sdata; mutex_lock(&local->iflist_mtx); list_for_each_entry(sdata, &local->interfaces, list) { switch (sdata->vif.type) { case NL80211_IFTYPE_MONITOR: case NL80211_IFTYPE_AP_VLAN: continue; default: break; } if (ieee80211_sdata_running(sdata)) iterator(data, sdata->vif.addr, &sdata->vif); } mutex_unlock(&local->iflist_mtx); } EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces); void ieee80211_iterate_active_interfaces_atomic( struct ieee80211_hw *hw, void (*iterator)(void *data, u8 *mac, struct ieee80211_vif *vif), void *data) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_sub_if_data *sdata; rcu_read_lock(); list_for_each_entry_rcu(sdata, &local->interfaces, list) { switch (sdata->vif.type) { case NL80211_IFTYPE_MONITOR: case NL80211_IFTYPE_AP_VLAN: continue; default: break; } if (ieee80211_sdata_running(sdata)) iterator(data, sdata->vif.addr, &sdata->vif); } rcu_read_unlock(); } EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces_atomic); /* * Nothing should have been stuffed into the workqueue during * the suspend->resume cycle. If this WARN is seen then there * is a bug with either the driver suspend or something in * mac80211 stuffing into the workqueue which we haven't yet * cleared during mac80211's suspend cycle. */ static bool ieee80211_can_queue_work(struct ieee80211_local *local) { if (WARN(local->suspended && !local->resuming, "queueing ieee80211 work while going to suspend\n")) return false; return true; } void ieee80211_queue_work(struct ieee80211_hw *hw, struct work_struct *work) { struct ieee80211_local *local = hw_to_local(hw); if (!ieee80211_can_queue_work(local)) return; queue_work(local->workqueue, work); } EXPORT_SYMBOL(ieee80211_queue_work); void ieee80211_queue_delayed_work(struct ieee80211_hw *hw, struct delayed_work *dwork, unsigned long delay) { struct ieee80211_local *local = hw_to_local(hw); if (!ieee80211_can_queue_work(local)) return; queue_delayed_work(local->workqueue, dwork, delay); } EXPORT_SYMBOL(ieee80211_queue_delayed_work); u32 ieee802_11_parse_elems_crc(u8 *start, size_t len, struct ieee802_11_elems *elems, u64 filter, u32 crc) { size_t left = len; u8 *pos = start; bool calc_crc = filter != 0; memset(elems, 0, sizeof(*elems)); elems->ie_start = start; elems->total_len = len; while (left >= 2) { u8 id, elen; id = *pos++; elen = *pos++; left -= 2; if (elen > left) break; if (calc_crc && id < 64 && (filter & (1ULL << id))) crc = crc32_be(crc, pos - 2, elen + 2); switch (id) { case WLAN_EID_SSID: elems->ssid = pos; elems->ssid_len = elen; break; case WLAN_EID_SUPP_RATES: elems->supp_rates = pos; elems->supp_rates_len = elen; break; case WLAN_EID_FH_PARAMS: elems->fh_params = pos; elems->fh_params_len = elen; break; case WLAN_EID_DS_PARAMS: elems->ds_params = pos; elems->ds_params_len = elen; break; case WLAN_EID_CF_PARAMS: elems->cf_params = pos; elems->cf_params_len = elen; break; case WLAN_EID_TIM: if (elen >= sizeof(struct ieee80211_tim_ie)) { elems->tim = (void *)pos; elems->tim_len = elen; } break; case WLAN_EID_IBSS_PARAMS: elems->ibss_params = pos; elems->ibss_params_len = elen; break; case WLAN_EID_CHALLENGE: elems->challenge = pos; elems->challenge_len = elen; break; case WLAN_EID_VENDOR_SPECIFIC: if (elen >= 4 && pos[0] == 0x00 && pos[1] == 0x50 && pos[2] == 0xf2) { /* Microsoft OUI (00:50:F2) */ if (calc_crc) crc = crc32_be(crc, pos - 2, elen + 2); if (pos[3] == 1) { /* OUI Type 1 - WPA IE */ elems->wpa = pos; elems->wpa_len = elen; } else if (elen >= 5 && pos[3] == 2) { /* OUI Type 2 - WMM IE */ if (pos[4] == 0) { elems->wmm_info = pos; elems->wmm_info_len = elen; } else if (pos[4] == 1) { elems->wmm_param = pos; elems->wmm_param_len = elen; } } } break; case WLAN_EID_RSN: elems->rsn = pos; elems->rsn_len = elen; break; case WLAN_EID_ERP_INFO: elems->erp_info = pos; elems->erp_info_len = elen; break; case WLAN_EID_EXT_SUPP_RATES: elems->ext_supp_rates = pos; elems->ext_supp_rates_len = elen; break; case WLAN_EID_HT_CAPABILITY: if (elen >= sizeof(struct ieee80211_ht_cap)) elems->ht_cap_elem = (void *)pos; break; case WLAN_EID_HT_INFORMATION: if (elen >= sizeof(struct ieee80211_ht_info)) elems->ht_info_elem = (void *)pos; break; case WLAN_EID_MESH_ID: elems->mesh_id = pos; elems->mesh_id_len = elen; break; case WLAN_EID_MESH_CONFIG: if (elen >= sizeof(struct ieee80211_meshconf_ie)) elems->mesh_config = (void *)pos; break; case WLAN_EID_PEER_MGMT: elems->peering = pos; elems->peering_len = elen; break; case WLAN_EID_PREQ: elems->preq = pos; elems->preq_len = elen; break; case WLAN_EID_PREP: elems->prep = pos; elems->prep_len = elen; break; case WLAN_EID_PERR: elems->perr = pos; elems->perr_len = elen; break; case WLAN_EID_RANN: if (elen >= sizeof(struct ieee80211_rann_ie)) elems->rann = (void *)pos; break; case WLAN_EID_CHANNEL_SWITCH: elems->ch_switch_elem = pos; elems->ch_switch_elem_len = elen; break; case WLAN_EID_QUIET: if (!elems->quiet_elem) { elems->quiet_elem = pos; elems->quiet_elem_len = elen; } elems->num_of_quiet_elem++; break; case WLAN_EID_COUNTRY: elems->country_elem = pos; elems->country_elem_len = elen; break; case WLAN_EID_PWR_CONSTRAINT: elems->pwr_constr_elem = pos; elems->pwr_constr_elem_len = elen; break; case WLAN_EID_TIMEOUT_INTERVAL: elems->timeout_int = pos; elems->timeout_int_len = elen; break; default: break; } left -= elen; pos += elen; } return crc; } void ieee802_11_parse_elems(u8 *start, size_t len, struct ieee802_11_elems *elems) { ieee802_11_parse_elems_crc(start, len, elems, 0, 0); } void ieee80211_set_wmm_default(struct ieee80211_sub_if_data *sdata) { struct ieee80211_local *local = sdata->local; struct ieee80211_tx_queue_params qparam; int queue; bool use_11b; int aCWmin, aCWmax; if (!local->ops->conf_tx) return; memset(&qparam, 0, sizeof(qparam)); use_11b = (local->hw.conf.channel->band == IEEE80211_BAND_2GHZ) && !(sdata->flags & IEEE80211_SDATA_OPERATING_GMODE); for (queue = 0; queue < local_to_hw(local)->queues; queue++) { /* Set defaults according to 802.11-2007 Table 7-37 */ aCWmax = 1023; if (use_11b) aCWmin = 31; else aCWmin = 15; switch (queue) { case 3: /* AC_BK */ qparam.cw_max = aCWmax; qparam.cw_min = aCWmin; qparam.txop = 0; qparam.aifs = 7; break; default: /* never happens but let's not leave undefined */ case 2: /* AC_BE */ qparam.cw_max = aCWmax; qparam.cw_min = aCWmin; qparam.txop = 0; qparam.aifs = 3; break; case 1: /* AC_VI */ qparam.cw_max = aCWmin; qparam.cw_min = (aCWmin + 1) / 2 - 1; if (use_11b) qparam.txop = 6016/32; else qparam.txop = 3008/32; qparam.aifs = 2; break; case 0: /* AC_VO */ qparam.cw_max = (aCWmin + 1) / 2 - 1; qparam.cw_min = (aCWmin + 1) / 4 - 1; if (use_11b) qparam.txop = 3264/32; else qparam.txop = 1504/32; qparam.aifs = 2; break; } qparam.uapsd = false; sdata->tx_conf[queue] = qparam; drv_conf_tx(local, sdata, queue, &qparam); } /* after reinitialize QoS TX queues setting to default, * disable QoS at all */ if (sdata->vif.type != NL80211_IFTYPE_MONITOR) { sdata->vif.bss_conf.qos = sdata->vif.type != NL80211_IFTYPE_STATION; ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_QOS); } } void ieee80211_sta_def_wmm_params(struct ieee80211_sub_if_data *sdata, const size_t supp_rates_len, const u8 *supp_rates) { struct ieee80211_local *local = sdata->local; int i, have_higher_than_11mbit = 0; /* cf. IEEE 802.11 9.2.12 */ for (i = 0; i < supp_rates_len; i++) if ((supp_rates[i] & 0x7f) * 5 > 110) have_higher_than_11mbit = 1; if (local->hw.conf.channel->band == IEEE80211_BAND_2GHZ && have_higher_than_11mbit) sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE; else sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE; ieee80211_set_wmm_default(sdata); } u32 ieee80211_mandatory_rates(struct ieee80211_local *local, enum ieee80211_band band) { struct ieee80211_supported_band *sband; struct ieee80211_rate *bitrates; u32 mandatory_rates; enum ieee80211_rate_flags mandatory_flag; int i; sband = local->hw.wiphy->bands[band]; if (!sband) { WARN_ON(1); sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; } if (band == IEEE80211_BAND_2GHZ) mandatory_flag = IEEE80211_RATE_MANDATORY_B; else mandatory_flag = IEEE80211_RATE_MANDATORY_A; bitrates = sband->bitrates; mandatory_rates = 0; for (i = 0; i < sband->n_bitrates; i++) if (bitrates[i].flags & mandatory_flag) mandatory_rates |= BIT(i); return mandatory_rates; } void ieee80211_send_auth(struct ieee80211_sub_if_data *sdata, u16 transaction, u16 auth_alg, u8 *extra, size_t extra_len, const u8 *da, const u8 *bssid, const u8 *key, u8 key_len, u8 key_idx) { struct ieee80211_local *local = sdata->local; struct sk_buff *skb; struct ieee80211_mgmt *mgmt; int err; skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt) + 6 + extra_len); if (!skb) return; skb_reserve(skb, local->hw.extra_tx_headroom); mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24 + 6); memset(mgmt, 0, 24 + 6); mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_AUTH); memcpy(mgmt->da, da, ETH_ALEN); memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); memcpy(mgmt->bssid, bssid, ETH_ALEN); mgmt->u.auth.auth_alg = cpu_to_le16(auth_alg); mgmt->u.auth.auth_transaction = cpu_to_le16(transaction); mgmt->u.auth.status_code = cpu_to_le16(0); if (extra) memcpy(skb_put(skb, extra_len), extra, extra_len); if (auth_alg == WLAN_AUTH_SHARED_KEY && transaction == 3) { mgmt->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED); err = ieee80211_wep_encrypt(local, skb, key, key_len, key_idx); WARN_ON(err); } IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; ieee80211_tx_skb(sdata, skb); } int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer, const u8 *ie, size_t ie_len, enum ieee80211_band band, u32 rate_mask, u8 channel) { struct ieee80211_supported_band *sband; u8 *pos; size_t offset = 0, noffset; int supp_rates_len, i; u8 rates[32]; int num_rates; int ext_rates_len; sband = local->hw.wiphy->bands[band]; pos = buffer; num_rates = 0; for (i = 0; i < sband->n_bitrates; i++) { if ((BIT(i) & rate_mask) == 0) continue; /* skip rate */ rates[num_rates++] = (u8) (sband->bitrates[i].bitrate / 5); } supp_rates_len = min_t(int, num_rates, 8); *pos++ = WLAN_EID_SUPP_RATES; *pos++ = supp_rates_len; memcpy(pos, rates, supp_rates_len); pos += supp_rates_len; /* insert "request information" if in custom IEs */ if (ie && ie_len) { static const u8 before_extrates[] = { WLAN_EID_SSID, WLAN_EID_SUPP_RATES, WLAN_EID_REQUEST, }; noffset = ieee80211_ie_split(ie, ie_len, before_extrates, ARRAY_SIZE(before_extrates), offset); memcpy(pos, ie + offset, noffset - offset); pos += noffset - offset; offset = noffset; } ext_rates_len = num_rates - supp_rates_len; if (ext_rates_len > 0) { *pos++ = WLAN_EID_EXT_SUPP_RATES; *pos++ = ext_rates_len; memcpy(pos, rates + supp_rates_len, ext_rates_len); pos += ext_rates_len; } if (channel && sband->band == IEEE80211_BAND_2GHZ) { *pos++ = WLAN_EID_DS_PARAMS; *pos++ = 1; *pos++ = channel; } /* insert custom IEs that go before HT */ if (ie && ie_len) { static const u8 before_ht[] = { WLAN_EID_SSID, WLAN_EID_SUPP_RATES, WLAN_EID_REQUEST, WLAN_EID_EXT_SUPP_RATES, WLAN_EID_DS_PARAMS, WLAN_EID_SUPPORTED_REGULATORY_CLASSES, }; noffset = ieee80211_ie_split(ie, ie_len, before_ht, ARRAY_SIZE(before_ht), offset); memcpy(pos, ie + offset, noffset - offset); pos += noffset - offset; offset = noffset; } if (sband->ht_cap.ht_supported) pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap); /* * If adding more here, adjust code in main.c * that calculates local->scan_ies_len. */ /* add any remaining custom IEs */ if (ie && ie_len) { noffset = ie_len; memcpy(pos, ie + offset, noffset - offset); pos += noffset - offset; } return pos - buffer; } struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst, u32 ratemask, const u8 *ssid, size_t ssid_len, const u8 *ie, size_t ie_len, bool directed) { struct ieee80211_local *local = sdata->local; struct sk_buff *skb; struct ieee80211_mgmt *mgmt; size_t buf_len; u8 *buf; u8 chan; /* FIXME: come up with a proper value */ buf = kmalloc(200 + ie_len, GFP_KERNEL); if (!buf) return NULL; /* * Do not send DS Channel parameter for directed probe requests * in order to maximize the chance that we get a response. Some * badly-behaved APs don't respond when this parameter is included. */ if (directed) chan = 0; else chan = ieee80211_frequency_to_channel( local->hw.conf.channel->center_freq); buf_len = ieee80211_build_preq_ies(local, buf, ie, ie_len, local->hw.conf.channel->band, ratemask, chan); skb = ieee80211_probereq_get(&local->hw, &sdata->vif, ssid, ssid_len, buf, buf_len); if (!skb) goto out; if (dst) { mgmt = (struct ieee80211_mgmt *) skb->data; memcpy(mgmt->da, dst, ETH_ALEN); memcpy(mgmt->bssid, dst, ETH_ALEN); } IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; out: kfree(buf); return skb; } void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst, const u8 *ssid, size_t ssid_len, const u8 *ie, size_t ie_len, u32 ratemask, bool directed, bool no_cck) { struct sk_buff *skb; skb = ieee80211_build_probe_req(sdata, dst, ratemask, ssid, ssid_len, ie, ie_len, directed); if (skb) { if (no_cck) IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_CCK_RATE; ieee80211_tx_skb(sdata, skb); } } u32 ieee80211_sta_get_rates(struct ieee80211_local *local, struct ieee802_11_elems *elems, enum ieee80211_band band) { struct ieee80211_supported_band *sband; struct ieee80211_rate *bitrates; size_t num_rates; u32 supp_rates; int i, j; sband = local->hw.wiphy->bands[band]; if (!sband) { WARN_ON(1); sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; } bitrates = sband->bitrates; num_rates = sband->n_bitrates; supp_rates = 0; for (i = 0; i < elems->supp_rates_len + elems->ext_supp_rates_len; i++) { u8 rate = 0; int own_rate; if (i < elems->supp_rates_len) rate = elems->supp_rates[i]; else if (elems->ext_supp_rates) rate = elems->ext_supp_rates [i - elems->supp_rates_len]; own_rate = 5 * (rate & 0x7f); for (j = 0; j < num_rates; j++) if (bitrates[j].bitrate == own_rate) supp_rates |= BIT(j); } return supp_rates; } void ieee80211_stop_device(struct ieee80211_local *local) { ieee80211_led_radio(local, false); ieee80211_mod_tpt_led_trig(local, 0, IEEE80211_TPT_LEDTRIG_FL_RADIO); cancel_work_sync(&local->reconfig_filter); flush_workqueue(local->workqueue); drv_stop(local); } int ieee80211_reconfig(struct ieee80211_local *local) { struct ieee80211_hw *hw = &local->hw; struct ieee80211_sub_if_data *sdata; struct sta_info *sta; int res, i; #ifdef CONFIG_PM if (local->suspended) local->resuming = true; if (local->wowlan) { local->wowlan = false; res = drv_resume(local); if (res < 0) { local->resuming = false; return res; } if (res == 0) goto wake_up; WARN_ON(res > 1); /* * res is 1, which means the driver requested * to go through a regular reset on wakeup. */ } #endif /* everything else happens only if HW was up & running */ if (!local->open_count) goto wake_up; /* * Upon resume hardware can sometimes be goofy due to * various platform / driver / bus issues, so restarting * the device may at times not work immediately. Propagate * the error. */ res = drv_start(local); if (res) { WARN(local->suspended, "Hardware became unavailable " "upon resume. This could be a software issue " "prior to suspend or a hardware issue.\n"); return res; } /* setup fragmentation threshold */ drv_set_frag_threshold(local, hw->wiphy->frag_threshold); /* setup RTS threshold */ drv_set_rts_threshold(local, hw->wiphy->rts_threshold); /* reset coverage class */ drv_set_coverage_class(local, hw->wiphy->coverage_class); ieee80211_led_radio(local, true); ieee80211_mod_tpt_led_trig(local, IEEE80211_TPT_LEDTRIG_FL_RADIO, 0); /* add interfaces */ list_for_each_entry(sdata, &local->interfaces, list) { if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN && sdata->vif.type != NL80211_IFTYPE_MONITOR && ieee80211_sdata_running(sdata)) res = drv_add_interface(local, sdata); } /* add STAs back */ mutex_lock(&local->sta_mtx); list_for_each_entry(sta, &local->sta_list, list) { if (sta->uploaded) { sdata = sta->sdata; if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) sdata = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap); WARN_ON(drv_sta_add(local, sdata, &sta->sta)); } } mutex_unlock(&local->sta_mtx); /* reconfigure tx conf */ list_for_each_entry(sdata, &local->interfaces, list) { if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN || sdata->vif.type == NL80211_IFTYPE_MONITOR || !ieee80211_sdata_running(sdata)) continue; for (i = 0; i < hw->queues; i++) drv_conf_tx(local, sdata, i, &sdata->tx_conf[i]); } /* reconfigure hardware */ ieee80211_hw_config(local, ~0); ieee80211_configure_filter(local); /* Finally also reconfigure all the BSS information */ list_for_each_entry(sdata, &local->interfaces, list) { u32 changed; if (!ieee80211_sdata_running(sdata)) continue; /* common change flags for all interface types */ changed = BSS_CHANGED_ERP_CTS_PROT | BSS_CHANGED_ERP_PREAMBLE | BSS_CHANGED_ERP_SLOT | BSS_CHANGED_HT | BSS_CHANGED_BASIC_RATES | BSS_CHANGED_BEACON_INT | BSS_CHANGED_BSSID | BSS_CHANGED_CQM | BSS_CHANGED_QOS | BSS_CHANGED_IDLE; switch (sdata->vif.type) { case NL80211_IFTYPE_STATION: changed |= BSS_CHANGED_ASSOC | BSS_CHANGED_ARP_FILTER; mutex_lock(&sdata->u.mgd.mtx); ieee80211_bss_info_change_notify(sdata, changed); mutex_unlock(&sdata->u.mgd.mtx); break; case NL80211_IFTYPE_ADHOC: changed |= BSS_CHANGED_IBSS; /* fall through */ case NL80211_IFTYPE_AP: changed |= BSS_CHANGED_SSID; if (sdata->vif.type == NL80211_IFTYPE_AP) changed |= BSS_CHANGED_AP_PROBE_RESP; /* fall through */ case NL80211_IFTYPE_MESH_POINT: changed |= BSS_CHANGED_BEACON | BSS_CHANGED_BEACON_ENABLED; ieee80211_bss_info_change_notify(sdata, changed); break; case NL80211_IFTYPE_WDS: break; case NL80211_IFTYPE_AP_VLAN: case NL80211_IFTYPE_MONITOR: /* ignore virtual */ break; case NL80211_IFTYPE_UNSPECIFIED: case NUM_NL80211_IFTYPES: case NL80211_IFTYPE_P2P_CLIENT: case NL80211_IFTYPE_P2P_GO: WARN_ON(1); break; } } ieee80211_recalc_ps(local, -1); /* * The sta might be in psm against the ap (e.g. because * this was the state before a hw restart), so we * explicitly send a null packet in order to make sure * it'll sync against the ap (and get out of psm). */ if (!(local->hw.conf.flags & IEEE80211_CONF_PS)) { list_for_each_entry(sdata, &local->interfaces, list) { if (sdata->vif.type != NL80211_IFTYPE_STATION) continue; ieee80211_send_nullfunc(local, sdata, 0); } } /* * Clear the WLAN_STA_BLOCK_BA flag so new aggregation * sessions can be established after a resume. * * Also tear down aggregation sessions since reconfiguring * them in a hardware restart scenario is not easily done * right now, and the hardware will have lost information * about the sessions, but we and the AP still think they * are active. This is really a workaround though. */ if (hw->flags & IEEE80211_HW_AMPDU_AGGREGATION) { mutex_lock(&local->sta_mtx); list_for_each_entry(sta, &local->sta_list, list) { ieee80211_sta_tear_down_BA_sessions(sta, true); clear_sta_flag(sta, WLAN_STA_BLOCK_BA); } mutex_unlock(&local->sta_mtx); } /* add back keys */ list_for_each_entry(sdata, &local->interfaces, list) if (ieee80211_sdata_running(sdata)) ieee80211_enable_keys(sdata); wake_up: ieee80211_wake_queues_by_reason(hw, IEEE80211_QUEUE_STOP_REASON_SUSPEND); /* * If this is for hw restart things are still running. * We may want to change that later, however. */ if (!local->suspended) return 0; #ifdef CONFIG_PM /* first set suspended false, then resuming */ local->suspended = false; mb(); local->resuming = false; list_for_each_entry(sdata, &local->interfaces, list) { switch(sdata->vif.type) { case NL80211_IFTYPE_STATION: ieee80211_sta_restart(sdata); break; case NL80211_IFTYPE_ADHOC: ieee80211_ibss_restart(sdata); break; case NL80211_IFTYPE_MESH_POINT: ieee80211_mesh_restart(sdata); break; default: break; } } mod_timer(&local->sta_cleanup, jiffies + 1); mutex_lock(&local->sta_mtx); list_for_each_entry(sta, &local->sta_list, list) mesh_plink_restart(sta); mutex_unlock(&local->sta_mtx); #else WARN_ON(1); #endif return 0; } void ieee80211_resume_disconnect(struct ieee80211_vif *vif) { struct ieee80211_sub_if_data *sdata; struct ieee80211_local *local; struct ieee80211_key *key; if (WARN_ON(!vif)) return; sdata = vif_to_sdata(vif); local = sdata->local; if (WARN_ON(!local->resuming)) return; if (WARN_ON(vif->type != NL80211_IFTYPE_STATION)) return; sdata->flags |= IEEE80211_SDATA_DISCONNECT_RESUME; mutex_lock(&local->key_mtx); list_for_each_entry(key, &sdata->key_list, list) key->flags |= KEY_FLAG_TAINTED; mutex_unlock(&local->key_mtx); } EXPORT_SYMBOL_GPL(ieee80211_resume_disconnect); static int check_mgd_smps(struct ieee80211_if_managed *ifmgd, enum ieee80211_smps_mode *smps_mode) { if (ifmgd->associated) { *smps_mode = ifmgd->ap_smps; if (*smps_mode == IEEE80211_SMPS_AUTOMATIC) { if (ifmgd->powersave) *smps_mode = IEEE80211_SMPS_DYNAMIC; else *smps_mode = IEEE80211_SMPS_OFF; } return 1; } return 0; } /* must hold iflist_mtx */ void ieee80211_recalc_smps(struct ieee80211_local *local) { struct ieee80211_sub_if_data *sdata; enum ieee80211_smps_mode smps_mode = IEEE80211_SMPS_OFF; int count = 0; lockdep_assert_held(&local->iflist_mtx); /* * This function could be improved to handle multiple * interfaces better, but right now it makes any * non-station interfaces force SM PS to be turned * off. If there are multiple station interfaces it * could also use the best possible mode, e.g. if * one is in static and the other in dynamic then * dynamic is ok. */ list_for_each_entry(sdata, &local->interfaces, list) { if (!ieee80211_sdata_running(sdata)) continue; if (sdata->vif.type != NL80211_IFTYPE_STATION) goto set; count += check_mgd_smps(&sdata->u.mgd, &smps_mode); if (count > 1) { smps_mode = IEEE80211_SMPS_OFF; break; } } if (smps_mode == local->smps_mode) return; set: local->smps_mode = smps_mode; /* changed flag is auto-detected for this */ ieee80211_hw_config(local, 0); } static bool ieee80211_id_in_list(const u8 *ids, int n_ids, u8 id) { int i; for (i = 0; i < n_ids; i++) if (ids[i] == id) return true; return false; } /** * ieee80211_ie_split - split an IE buffer according to ordering * * @ies: the IE buffer * @ielen: the length of the IE buffer * @ids: an array with element IDs that are allowed before * the split * @n_ids: the size of the element ID array * @offset: offset where to start splitting in the buffer * * This function splits an IE buffer by updating the @offset * variable to point to the location where the buffer should be * split. * * It assumes that the given IE buffer is well-formed, this * has to be guaranteed by the caller! * * It also assumes that the IEs in the buffer are ordered * correctly, if not the result of using this function will not * be ordered correctly either, i.e. it does no reordering. * * The function returns the offset where the next part of the * buffer starts, which may be @ielen if the entire (remainder) * of the buffer should be used. */ size_t ieee80211_ie_split(const u8 *ies, size_t ielen, const u8 *ids, int n_ids, size_t offset) { size_t pos = offset; while (pos < ielen && ieee80211_id_in_list(ids, n_ids, ies[pos])) pos += 2 + ies[pos + 1]; return pos; } size_t ieee80211_ie_split_vendor(const u8 *ies, size_t ielen, size_t offset) { size_t pos = offset; while (pos < ielen && ies[pos] != WLAN_EID_VENDOR_SPECIFIC) pos += 2 + ies[pos + 1]; return pos; } static void _ieee80211_enable_rssi_reports(struct ieee80211_sub_if_data *sdata, int rssi_min_thold, int rssi_max_thold) { trace_api_enable_rssi_reports(sdata, rssi_min_thold, rssi_max_thold); if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_STATION)) return; /* * Scale up threshold values before storing it, as the RSSI averaging * algorithm uses a scaled up value as well. Change this scaling * factor if the RSSI averaging algorithm changes. */ sdata->u.mgd.rssi_min_thold = rssi_min_thold*16; sdata->u.mgd.rssi_max_thold = rssi_max_thold*16; } void ieee80211_enable_rssi_reports(struct ieee80211_vif *vif, int rssi_min_thold, int rssi_max_thold) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); WARN_ON(rssi_min_thold == rssi_max_thold || rssi_min_thold > rssi_max_thold); _ieee80211_enable_rssi_reports(sdata, rssi_min_thold, rssi_max_thold); } EXPORT_SYMBOL(ieee80211_enable_rssi_reports); void ieee80211_disable_rssi_reports(struct ieee80211_vif *vif) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); _ieee80211_enable_rssi_reports(sdata, 0, 0); } EXPORT_SYMBOL(ieee80211_disable_rssi_reports); u8 *ieee80211_ie_build_ht_cap(u8 *pos, struct ieee80211_sta_ht_cap *ht_cap, u16 cap) { __le16 tmp; *pos++ = WLAN_EID_HT_CAPABILITY; *pos++ = sizeof(struct ieee80211_ht_cap); memset(pos, 0, sizeof(struct ieee80211_ht_cap)); /* capability flags */ tmp = cpu_to_le16(cap); memcpy(pos, &tmp, sizeof(u16)); pos += sizeof(u16); /* AMPDU parameters */ *pos++ = ht_cap->ampdu_factor | (ht_cap->ampdu_density << IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT); /* MCS set */ memcpy(pos, &ht_cap->mcs, sizeof(ht_cap->mcs)); pos += sizeof(ht_cap->mcs); /* extended capabilities */ pos += sizeof(__le16); /* BF capabilities */ pos += sizeof(__le32); /* antenna selection */ pos += sizeof(u8); return pos; } u8 *ieee80211_ie_build_ht_info(u8 *pos, struct ieee80211_sta_ht_cap *ht_cap, struct ieee80211_channel *channel, enum nl80211_channel_type channel_type) { struct ieee80211_ht_info *ht_info; /* Build HT Information */ *pos++ = WLAN_EID_HT_INFORMATION; *pos++ = sizeof(struct ieee80211_ht_info); ht_info = (struct ieee80211_ht_info *)pos; ht_info->control_chan = ieee80211_frequency_to_channel(channel->center_freq); switch (channel_type) { case NL80211_CHAN_HT40MINUS: ht_info->ht_param = IEEE80211_HT_PARAM_CHA_SEC_BELOW; break; case NL80211_CHAN_HT40PLUS: ht_info->ht_param = IEEE80211_HT_PARAM_CHA_SEC_ABOVE; break; case NL80211_CHAN_HT20: default: ht_info->ht_param = IEEE80211_HT_PARAM_CHA_SEC_NONE; break; } if (ht_cap->cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) ht_info->ht_param |= IEEE80211_HT_PARAM_CHAN_WIDTH_ANY; /* * Note: According to 802.11n-2009 9.13.3.1, HT Protection field and * RIFS Mode are reserved in IBSS mode, therefore keep them at 0 */ ht_info->operation_mode = 0x0000; ht_info->stbc_param = 0x0000; /* It seems that Basic MCS set and Supported MCS set are identical for the first 10 bytes */ memset(&ht_info->basic_set, 0, 16); memcpy(&ht_info->basic_set, &ht_cap->mcs, 10); return pos + sizeof(struct ieee80211_ht_info); } enum nl80211_channel_type ieee80211_ht_info_to_channel_type(struct ieee80211_ht_info *ht_info) { enum nl80211_channel_type channel_type; if (!ht_info) return NL80211_CHAN_NO_HT; switch (ht_info->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) { case IEEE80211_HT_PARAM_CHA_SEC_NONE: channel_type = NL80211_CHAN_HT20; break; case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: channel_type = NL80211_CHAN_HT40PLUS; break; case IEEE80211_HT_PARAM_CHA_SEC_BELOW: channel_type = NL80211_CHAN_HT40MINUS; break; default: channel_type = NL80211_CHAN_NO_HT; } return channel_type; } int ieee80211_add_srates_ie(struct ieee80211_vif *vif, struct sk_buff *skb) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); struct ieee80211_local *local = sdata->local; struct ieee80211_supported_band *sband; int rate; u8 i, rates, *pos; sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; rates = sband->n_bitrates; if (rates > 8) rates = 8; if (skb_tailroom(skb) < rates + 2) return -ENOMEM; pos = skb_put(skb, rates + 2); *pos++ = WLAN_EID_SUPP_RATES; *pos++ = rates; for (i = 0; i < rates; i++) { rate = sband->bitrates[i].bitrate; *pos++ = (u8) (rate / 5); } return 0; } int ieee80211_add_ext_srates_ie(struct ieee80211_vif *vif, struct sk_buff *skb) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); struct ieee80211_local *local = sdata->local; struct ieee80211_supported_band *sband; int rate; u8 i, exrates, *pos; sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; exrates = sband->n_bitrates; if (exrates > 8) exrates -= 8; else exrates = 0; if (skb_tailroom(skb) < exrates + 2) return -ENOMEM; if (exrates) { pos = skb_put(skb, exrates + 2); *pos++ = WLAN_EID_EXT_SUPP_RATES; *pos++ = exrates; for (i = 8; i < sband->n_bitrates; i++) { rate = sband->bitrates[i].bitrate; *pos++ = (u8) (rate / 5); } } return 0; }