1 /* 2 * spectrum management 3 * 4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> 5 * Copyright 2002-2005, Instant802 Networks, Inc. 6 * Copyright 2005-2006, Devicescape Software, Inc. 7 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 8 * Copyright 2007, Michael Wu <flamingice@sourmilk.net> 9 * Copyright 2007-2008, Intel Corporation 10 * Copyright 2008, Johannes Berg <johannes@sipsolutions.net> 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License version 2 as 14 * published by the Free Software Foundation. 15 */ 16 17 #include <linux/ieee80211.h> 18 #include <net/cfg80211.h> 19 #include <net/mac80211.h> 20 #include "ieee80211_i.h" 21 #include "sta_info.h" 22 #include "wme.h" 23 24 int ieee80211_parse_ch_switch_ie(struct ieee80211_sub_if_data *sdata, 25 struct ieee802_11_elems *elems, bool beacon, 26 enum ieee80211_band current_band, 27 u32 sta_flags, u8 *bssid, 28 struct ieee80211_csa_ie *csa_ie) 29 { 30 enum ieee80211_band new_band; 31 int new_freq; 32 u8 new_chan_no; 33 struct ieee80211_channel *new_chan; 34 struct cfg80211_chan_def new_vht_chandef = {}; 35 const struct ieee80211_sec_chan_offs_ie *sec_chan_offs; 36 const struct ieee80211_wide_bw_chansw_ie *wide_bw_chansw_ie; 37 const struct ieee80211_ht_operation *ht_oper; 38 int secondary_channel_offset = -1; 39 40 sec_chan_offs = elems->sec_chan_offs; 41 wide_bw_chansw_ie = elems->wide_bw_chansw_ie; 42 ht_oper = elems->ht_operation; 43 44 if (sta_flags & (IEEE80211_STA_DISABLE_HT | 45 IEEE80211_STA_DISABLE_40MHZ)) { 46 sec_chan_offs = NULL; 47 wide_bw_chansw_ie = NULL; 48 /* only used for bandwidth here */ 49 ht_oper = NULL; 50 } 51 52 if (sta_flags & IEEE80211_STA_DISABLE_VHT) 53 wide_bw_chansw_ie = NULL; 54 55 if (elems->ext_chansw_ie) { 56 if (!ieee80211_operating_class_to_band( 57 elems->ext_chansw_ie->new_operating_class, 58 &new_band)) { 59 sdata_info(sdata, 60 "cannot understand ECSA IE operating class %d, disconnecting\n", 61 elems->ext_chansw_ie->new_operating_class); 62 return -EINVAL; 63 } 64 new_chan_no = elems->ext_chansw_ie->new_ch_num; 65 csa_ie->count = elems->ext_chansw_ie->count; 66 csa_ie->mode = elems->ext_chansw_ie->mode; 67 } else if (elems->ch_switch_ie) { 68 new_band = current_band; 69 new_chan_no = elems->ch_switch_ie->new_ch_num; 70 csa_ie->count = elems->ch_switch_ie->count; 71 csa_ie->mode = elems->ch_switch_ie->mode; 72 } else { 73 /* nothing here we understand */ 74 return 1; 75 } 76 77 /* Mesh Channel Switch Parameters Element */ 78 if (elems->mesh_chansw_params_ie) { 79 csa_ie->ttl = elems->mesh_chansw_params_ie->mesh_ttl; 80 csa_ie->mode = elems->mesh_chansw_params_ie->mesh_flags; 81 csa_ie->pre_value = le16_to_cpu( 82 elems->mesh_chansw_params_ie->mesh_pre_value); 83 } 84 85 new_freq = ieee80211_channel_to_frequency(new_chan_no, new_band); 86 new_chan = ieee80211_get_channel(sdata->local->hw.wiphy, new_freq); 87 if (!new_chan || new_chan->flags & IEEE80211_CHAN_DISABLED) { 88 sdata_info(sdata, 89 "BSS %pM switches to unsupported channel (%d MHz), disconnecting\n", 90 bssid, new_freq); 91 return -EINVAL; 92 } 93 94 if (!beacon && sec_chan_offs) { 95 secondary_channel_offset = sec_chan_offs->sec_chan_offs; 96 } else if (beacon && ht_oper) { 97 secondary_channel_offset = 98 ht_oper->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET; 99 } else if (!(sta_flags & IEEE80211_STA_DISABLE_HT)) { 100 /* If it's not a beacon, HT is enabled and the IE not present, 101 * it's 20 MHz, 802.11-2012 8.5.2.6: 102 * This element [the Secondary Channel Offset Element] is 103 * present when switching to a 40 MHz channel. It may be 104 * present when switching to a 20 MHz channel (in which 105 * case the secondary channel offset is set to SCN). 106 */ 107 secondary_channel_offset = IEEE80211_HT_PARAM_CHA_SEC_NONE; 108 } 109 110 switch (secondary_channel_offset) { 111 default: 112 /* secondary_channel_offset was present but is invalid */ 113 case IEEE80211_HT_PARAM_CHA_SEC_NONE: 114 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 115 NL80211_CHAN_HT20); 116 break; 117 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: 118 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 119 NL80211_CHAN_HT40PLUS); 120 break; 121 case IEEE80211_HT_PARAM_CHA_SEC_BELOW: 122 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 123 NL80211_CHAN_HT40MINUS); 124 break; 125 case -1: 126 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 127 NL80211_CHAN_NO_HT); 128 /* keep width for 5/10 MHz channels */ 129 switch (sdata->vif.bss_conf.chandef.width) { 130 case NL80211_CHAN_WIDTH_5: 131 case NL80211_CHAN_WIDTH_10: 132 csa_ie->chandef.width = 133 sdata->vif.bss_conf.chandef.width; 134 break; 135 default: 136 break; 137 } 138 break; 139 } 140 141 if (wide_bw_chansw_ie) { 142 new_vht_chandef.chan = new_chan; 143 new_vht_chandef.center_freq1 = 144 ieee80211_channel_to_frequency( 145 wide_bw_chansw_ie->new_center_freq_seg0, 146 new_band); 147 148 switch (wide_bw_chansw_ie->new_channel_width) { 149 default: 150 /* hmmm, ignore VHT and use HT if present */ 151 case IEEE80211_VHT_CHANWIDTH_USE_HT: 152 new_vht_chandef.chan = NULL; 153 break; 154 case IEEE80211_VHT_CHANWIDTH_80MHZ: 155 new_vht_chandef.width = NL80211_CHAN_WIDTH_80; 156 break; 157 case IEEE80211_VHT_CHANWIDTH_160MHZ: 158 new_vht_chandef.width = NL80211_CHAN_WIDTH_160; 159 break; 160 case IEEE80211_VHT_CHANWIDTH_80P80MHZ: 161 /* field is otherwise reserved */ 162 new_vht_chandef.center_freq2 = 163 ieee80211_channel_to_frequency( 164 wide_bw_chansw_ie->new_center_freq_seg1, 165 new_band); 166 new_vht_chandef.width = NL80211_CHAN_WIDTH_80P80; 167 break; 168 } 169 if (sta_flags & IEEE80211_STA_DISABLE_80P80MHZ && 170 new_vht_chandef.width == NL80211_CHAN_WIDTH_80P80) 171 ieee80211_chandef_downgrade(&new_vht_chandef); 172 if (sta_flags & IEEE80211_STA_DISABLE_160MHZ && 173 new_vht_chandef.width == NL80211_CHAN_WIDTH_160) 174 ieee80211_chandef_downgrade(&new_vht_chandef); 175 if (sta_flags & IEEE80211_STA_DISABLE_40MHZ && 176 new_vht_chandef.width > NL80211_CHAN_WIDTH_20) 177 ieee80211_chandef_downgrade(&new_vht_chandef); 178 } 179 180 /* if VHT data is there validate & use it */ 181 if (new_vht_chandef.chan) { 182 if (!cfg80211_chandef_compatible(&new_vht_chandef, 183 &csa_ie->chandef)) { 184 sdata_info(sdata, 185 "BSS %pM: CSA has inconsistent channel data, disconnecting\n", 186 bssid); 187 return -EINVAL; 188 } 189 csa_ie->chandef = new_vht_chandef; 190 } 191 192 return 0; 193 } 194 195 static void ieee80211_send_refuse_measurement_request(struct ieee80211_sub_if_data *sdata, 196 struct ieee80211_msrment_ie *request_ie, 197 const u8 *da, const u8 *bssid, 198 u8 dialog_token) 199 { 200 struct ieee80211_local *local = sdata->local; 201 struct sk_buff *skb; 202 struct ieee80211_mgmt *msr_report; 203 204 skb = dev_alloc_skb(sizeof(*msr_report) + local->hw.extra_tx_headroom + 205 sizeof(struct ieee80211_msrment_ie)); 206 if (!skb) 207 return; 208 209 skb_reserve(skb, local->hw.extra_tx_headroom); 210 msr_report = (struct ieee80211_mgmt *)skb_put(skb, 24); 211 memset(msr_report, 0, 24); 212 memcpy(msr_report->da, da, ETH_ALEN); 213 memcpy(msr_report->sa, sdata->vif.addr, ETH_ALEN); 214 memcpy(msr_report->bssid, bssid, ETH_ALEN); 215 msr_report->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 216 IEEE80211_STYPE_ACTION); 217 218 skb_put(skb, 1 + sizeof(msr_report->u.action.u.measurement)); 219 msr_report->u.action.category = WLAN_CATEGORY_SPECTRUM_MGMT; 220 msr_report->u.action.u.measurement.action_code = 221 WLAN_ACTION_SPCT_MSR_RPRT; 222 msr_report->u.action.u.measurement.dialog_token = dialog_token; 223 224 msr_report->u.action.u.measurement.element_id = WLAN_EID_MEASURE_REPORT; 225 msr_report->u.action.u.measurement.length = 226 sizeof(struct ieee80211_msrment_ie); 227 228 memset(&msr_report->u.action.u.measurement.msr_elem, 0, 229 sizeof(struct ieee80211_msrment_ie)); 230 msr_report->u.action.u.measurement.msr_elem.token = request_ie->token; 231 msr_report->u.action.u.measurement.msr_elem.mode |= 232 IEEE80211_SPCT_MSR_RPRT_MODE_REFUSED; 233 msr_report->u.action.u.measurement.msr_elem.type = request_ie->type; 234 235 ieee80211_tx_skb(sdata, skb); 236 } 237 238 void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata, 239 struct ieee80211_mgmt *mgmt, 240 size_t len) 241 { 242 /* 243 * Ignoring measurement request is spec violation. 244 * Mandatory measurements must be reported optional 245 * measurements might be refused or reported incapable 246 * For now just refuse 247 * TODO: Answer basic measurement as unmeasured 248 */ 249 ieee80211_send_refuse_measurement_request(sdata, 250 &mgmt->u.action.u.measurement.msr_elem, 251 mgmt->sa, mgmt->bssid, 252 mgmt->u.action.u.measurement.dialog_token); 253 } 254