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 * Copyright (C) 2018 Intel Corporation 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License version 2 as 15 * published by the Free Software Foundation. 16 */ 17 18 #include <linux/ieee80211.h> 19 #include <net/cfg80211.h> 20 #include <net/mac80211.h> 21 #include "ieee80211_i.h" 22 #include "sta_info.h" 23 #include "wme.h" 24 25 int ieee80211_parse_ch_switch_ie(struct ieee80211_sub_if_data *sdata, 26 struct ieee802_11_elems *elems, 27 enum nl80211_band current_band, 28 u32 sta_flags, u8 *bssid, 29 struct ieee80211_csa_ie *csa_ie) 30 { 31 enum nl80211_band new_band = current_band; 32 int new_freq; 33 u8 new_chan_no; 34 struct ieee80211_channel *new_chan; 35 struct cfg80211_chan_def new_vht_chandef = {}; 36 const struct ieee80211_sec_chan_offs_ie *sec_chan_offs; 37 const struct ieee80211_wide_bw_chansw_ie *wide_bw_chansw_ie; 38 int secondary_channel_offset = -1; 39 40 memset(csa_ie, 0, sizeof(*csa_ie)); 41 42 sec_chan_offs = elems->sec_chan_offs; 43 wide_bw_chansw_ie = elems->wide_bw_chansw_ie; 44 45 if (sta_flags & (IEEE80211_STA_DISABLE_HT | 46 IEEE80211_STA_DISABLE_40MHZ)) { 47 sec_chan_offs = NULL; 48 wide_bw_chansw_ie = NULL; 49 } 50 51 if (sta_flags & IEEE80211_STA_DISABLE_VHT) 52 wide_bw_chansw_ie = NULL; 53 54 if (elems->ext_chansw_ie) { 55 if (!ieee80211_operating_class_to_band( 56 elems->ext_chansw_ie->new_operating_class, 57 &new_band)) { 58 sdata_info(sdata, 59 "cannot understand ECSA IE operating class, %d, ignoring\n", 60 elems->ext_chansw_ie->new_operating_class); 61 } 62 new_chan_no = elems->ext_chansw_ie->new_ch_num; 63 csa_ie->count = elems->ext_chansw_ie->count; 64 csa_ie->mode = elems->ext_chansw_ie->mode; 65 } else if (elems->ch_switch_ie) { 66 new_chan_no = elems->ch_switch_ie->new_ch_num; 67 csa_ie->count = elems->ch_switch_ie->count; 68 csa_ie->mode = elems->ch_switch_ie->mode; 69 } else { 70 /* nothing here we understand */ 71 return 1; 72 } 73 74 /* Mesh Channel Switch Parameters Element */ 75 if (elems->mesh_chansw_params_ie) { 76 csa_ie->ttl = elems->mesh_chansw_params_ie->mesh_ttl; 77 csa_ie->mode = elems->mesh_chansw_params_ie->mesh_flags; 78 csa_ie->pre_value = le16_to_cpu( 79 elems->mesh_chansw_params_ie->mesh_pre_value); 80 81 if (elems->mesh_chansw_params_ie->mesh_flags & 82 WLAN_EID_CHAN_SWITCH_PARAM_REASON) 83 csa_ie->reason_code = le16_to_cpu( 84 elems->mesh_chansw_params_ie->mesh_reason); 85 } 86 87 new_freq = ieee80211_channel_to_frequency(new_chan_no, new_band); 88 new_chan = ieee80211_get_channel(sdata->local->hw.wiphy, new_freq); 89 if (!new_chan || new_chan->flags & IEEE80211_CHAN_DISABLED) { 90 sdata_info(sdata, 91 "BSS %pM switches to unsupported channel (%d MHz), disconnecting\n", 92 bssid, new_freq); 93 return -EINVAL; 94 } 95 96 if (sec_chan_offs) { 97 secondary_channel_offset = sec_chan_offs->sec_chan_offs; 98 } else if (!(sta_flags & IEEE80211_STA_DISABLE_HT)) { 99 /* If the secondary channel offset IE is not present, 100 * we can't know what's the post-CSA offset, so the 101 * best we can do is use 20MHz. 102 */ 103 secondary_channel_offset = IEEE80211_HT_PARAM_CHA_SEC_NONE; 104 } 105 106 switch (secondary_channel_offset) { 107 default: 108 /* secondary_channel_offset was present but is invalid */ 109 case IEEE80211_HT_PARAM_CHA_SEC_NONE: 110 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 111 NL80211_CHAN_HT20); 112 break; 113 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: 114 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 115 NL80211_CHAN_HT40PLUS); 116 break; 117 case IEEE80211_HT_PARAM_CHA_SEC_BELOW: 118 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 119 NL80211_CHAN_HT40MINUS); 120 break; 121 case -1: 122 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 123 NL80211_CHAN_NO_HT); 124 /* keep width for 5/10 MHz channels */ 125 switch (sdata->vif.bss_conf.chandef.width) { 126 case NL80211_CHAN_WIDTH_5: 127 case NL80211_CHAN_WIDTH_10: 128 csa_ie->chandef.width = 129 sdata->vif.bss_conf.chandef.width; 130 break; 131 default: 132 break; 133 } 134 break; 135 } 136 137 if (wide_bw_chansw_ie) { 138 struct ieee80211_vht_operation vht_oper = { 139 .chan_width = 140 wide_bw_chansw_ie->new_channel_width, 141 .center_freq_seg0_idx = 142 wide_bw_chansw_ie->new_center_freq_seg0, 143 .center_freq_seg1_idx = 144 wide_bw_chansw_ie->new_center_freq_seg1, 145 /* .basic_mcs_set doesn't matter */ 146 }; 147 struct ieee80211_ht_operation ht_oper = {}; 148 149 /* default, for the case of IEEE80211_VHT_CHANWIDTH_USE_HT, 150 * to the previously parsed chandef 151 */ 152 new_vht_chandef = csa_ie->chandef; 153 154 /* ignore if parsing fails */ 155 if (!ieee80211_chandef_vht_oper(&sdata->local->hw, 156 &vht_oper, &ht_oper, 157 &new_vht_chandef)) 158 new_vht_chandef.chan = NULL; 159 160 if (sta_flags & IEEE80211_STA_DISABLE_80P80MHZ && 161 new_vht_chandef.width == NL80211_CHAN_WIDTH_80P80) 162 ieee80211_chandef_downgrade(&new_vht_chandef); 163 if (sta_flags & IEEE80211_STA_DISABLE_160MHZ && 164 new_vht_chandef.width == NL80211_CHAN_WIDTH_160) 165 ieee80211_chandef_downgrade(&new_vht_chandef); 166 } 167 168 /* if VHT data is there validate & use it */ 169 if (new_vht_chandef.chan) { 170 if (!cfg80211_chandef_compatible(&new_vht_chandef, 171 &csa_ie->chandef)) { 172 sdata_info(sdata, 173 "BSS %pM: CSA has inconsistent channel data, disconnecting\n", 174 bssid); 175 return -EINVAL; 176 } 177 csa_ie->chandef = new_vht_chandef; 178 } 179 180 return 0; 181 } 182 183 static void ieee80211_send_refuse_measurement_request(struct ieee80211_sub_if_data *sdata, 184 struct ieee80211_msrment_ie *request_ie, 185 const u8 *da, const u8 *bssid, 186 u8 dialog_token) 187 { 188 struct ieee80211_local *local = sdata->local; 189 struct sk_buff *skb; 190 struct ieee80211_mgmt *msr_report; 191 192 skb = dev_alloc_skb(sizeof(*msr_report) + local->hw.extra_tx_headroom + 193 sizeof(struct ieee80211_msrment_ie)); 194 if (!skb) 195 return; 196 197 skb_reserve(skb, local->hw.extra_tx_headroom); 198 msr_report = skb_put_zero(skb, 24); 199 memcpy(msr_report->da, da, ETH_ALEN); 200 memcpy(msr_report->sa, sdata->vif.addr, ETH_ALEN); 201 memcpy(msr_report->bssid, bssid, ETH_ALEN); 202 msr_report->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 203 IEEE80211_STYPE_ACTION); 204 205 skb_put(skb, 1 + sizeof(msr_report->u.action.u.measurement)); 206 msr_report->u.action.category = WLAN_CATEGORY_SPECTRUM_MGMT; 207 msr_report->u.action.u.measurement.action_code = 208 WLAN_ACTION_SPCT_MSR_RPRT; 209 msr_report->u.action.u.measurement.dialog_token = dialog_token; 210 211 msr_report->u.action.u.measurement.element_id = WLAN_EID_MEASURE_REPORT; 212 msr_report->u.action.u.measurement.length = 213 sizeof(struct ieee80211_msrment_ie); 214 215 memset(&msr_report->u.action.u.measurement.msr_elem, 0, 216 sizeof(struct ieee80211_msrment_ie)); 217 msr_report->u.action.u.measurement.msr_elem.token = request_ie->token; 218 msr_report->u.action.u.measurement.msr_elem.mode |= 219 IEEE80211_SPCT_MSR_RPRT_MODE_REFUSED; 220 msr_report->u.action.u.measurement.msr_elem.type = request_ie->type; 221 222 ieee80211_tx_skb(sdata, skb); 223 } 224 225 void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata, 226 struct ieee80211_mgmt *mgmt, 227 size_t len) 228 { 229 /* 230 * Ignoring measurement request is spec violation. 231 * Mandatory measurements must be reported optional 232 * measurements might be refused or reported incapable 233 * For now just refuse 234 * TODO: Answer basic measurement as unmeasured 235 */ 236 ieee80211_send_refuse_measurement_request(sdata, 237 &mgmt->u.action.u.measurement.msr_elem, 238 mgmt->sa, mgmt->bssid, 239 mgmt->u.action.u.measurement.dialog_token); 240 } 241