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, 26 enum nl80211_band current_band, 27 u32 sta_flags, u8 *bssid, 28 struct ieee80211_csa_ie *csa_ie) 29 { 30 enum nl80211_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 int secondary_channel_offset = -1; 38 39 sec_chan_offs = elems->sec_chan_offs; 40 wide_bw_chansw_ie = elems->wide_bw_chansw_ie; 41 42 if (sta_flags & (IEEE80211_STA_DISABLE_HT | 43 IEEE80211_STA_DISABLE_40MHZ)) { 44 sec_chan_offs = NULL; 45 wide_bw_chansw_ie = NULL; 46 } 47 48 if (sta_flags & IEEE80211_STA_DISABLE_VHT) 49 wide_bw_chansw_ie = NULL; 50 51 if (elems->ext_chansw_ie) { 52 if (!ieee80211_operating_class_to_band( 53 elems->ext_chansw_ie->new_operating_class, 54 &new_band)) { 55 sdata_info(sdata, 56 "cannot understand ECSA IE operating class %d, disconnecting\n", 57 elems->ext_chansw_ie->new_operating_class); 58 return -EINVAL; 59 } 60 new_chan_no = elems->ext_chansw_ie->new_ch_num; 61 csa_ie->count = elems->ext_chansw_ie->count; 62 csa_ie->mode = elems->ext_chansw_ie->mode; 63 } else if (elems->ch_switch_ie) { 64 new_band = current_band; 65 new_chan_no = elems->ch_switch_ie->new_ch_num; 66 csa_ie->count = elems->ch_switch_ie->count; 67 csa_ie->mode = elems->ch_switch_ie->mode; 68 } else { 69 /* nothing here we understand */ 70 return 1; 71 } 72 73 /* Mesh Channel Switch Parameters Element */ 74 if (elems->mesh_chansw_params_ie) { 75 csa_ie->ttl = elems->mesh_chansw_params_ie->mesh_ttl; 76 csa_ie->mode = elems->mesh_chansw_params_ie->mesh_flags; 77 csa_ie->pre_value = le16_to_cpu( 78 elems->mesh_chansw_params_ie->mesh_pre_value); 79 } 80 81 new_freq = ieee80211_channel_to_frequency(new_chan_no, new_band); 82 new_chan = ieee80211_get_channel(sdata->local->hw.wiphy, new_freq); 83 if (!new_chan || new_chan->flags & IEEE80211_CHAN_DISABLED) { 84 sdata_info(sdata, 85 "BSS %pM switches to unsupported channel (%d MHz), disconnecting\n", 86 bssid, new_freq); 87 return -EINVAL; 88 } 89 90 if (sec_chan_offs) { 91 secondary_channel_offset = sec_chan_offs->sec_chan_offs; 92 } else if (!(sta_flags & IEEE80211_STA_DISABLE_HT)) { 93 /* If the secondary channel offset IE is not present, 94 * we can't know what's the post-CSA offset, so the 95 * best we can do is use 20MHz. 96 */ 97 secondary_channel_offset = IEEE80211_HT_PARAM_CHA_SEC_NONE; 98 } 99 100 switch (secondary_channel_offset) { 101 default: 102 /* secondary_channel_offset was present but is invalid */ 103 case IEEE80211_HT_PARAM_CHA_SEC_NONE: 104 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 105 NL80211_CHAN_HT20); 106 break; 107 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: 108 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 109 NL80211_CHAN_HT40PLUS); 110 break; 111 case IEEE80211_HT_PARAM_CHA_SEC_BELOW: 112 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 113 NL80211_CHAN_HT40MINUS); 114 break; 115 case -1: 116 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 117 NL80211_CHAN_NO_HT); 118 /* keep width for 5/10 MHz channels */ 119 switch (sdata->vif.bss_conf.chandef.width) { 120 case NL80211_CHAN_WIDTH_5: 121 case NL80211_CHAN_WIDTH_10: 122 csa_ie->chandef.width = 123 sdata->vif.bss_conf.chandef.width; 124 break; 125 default: 126 break; 127 } 128 break; 129 } 130 131 if (wide_bw_chansw_ie) { 132 new_vht_chandef.chan = new_chan; 133 new_vht_chandef.center_freq1 = 134 ieee80211_channel_to_frequency( 135 wide_bw_chansw_ie->new_center_freq_seg0, 136 new_band); 137 138 switch (wide_bw_chansw_ie->new_channel_width) { 139 default: 140 /* hmmm, ignore VHT and use HT if present */ 141 case IEEE80211_VHT_CHANWIDTH_USE_HT: 142 new_vht_chandef.chan = NULL; 143 break; 144 case IEEE80211_VHT_CHANWIDTH_80MHZ: 145 new_vht_chandef.width = NL80211_CHAN_WIDTH_80; 146 break; 147 case IEEE80211_VHT_CHANWIDTH_160MHZ: 148 new_vht_chandef.width = NL80211_CHAN_WIDTH_160; 149 break; 150 case IEEE80211_VHT_CHANWIDTH_80P80MHZ: 151 /* field is otherwise reserved */ 152 new_vht_chandef.center_freq2 = 153 ieee80211_channel_to_frequency( 154 wide_bw_chansw_ie->new_center_freq_seg1, 155 new_band); 156 new_vht_chandef.width = NL80211_CHAN_WIDTH_80P80; 157 break; 158 } 159 if (sta_flags & IEEE80211_STA_DISABLE_80P80MHZ && 160 new_vht_chandef.width == NL80211_CHAN_WIDTH_80P80) 161 ieee80211_chandef_downgrade(&new_vht_chandef); 162 if (sta_flags & IEEE80211_STA_DISABLE_160MHZ && 163 new_vht_chandef.width == NL80211_CHAN_WIDTH_160) 164 ieee80211_chandef_downgrade(&new_vht_chandef); 165 if (sta_flags & IEEE80211_STA_DISABLE_40MHZ && 166 new_vht_chandef.width > NL80211_CHAN_WIDTH_20) 167 ieee80211_chandef_downgrade(&new_vht_chandef); 168 } 169 170 /* if VHT data is there validate & use it */ 171 if (new_vht_chandef.chan) { 172 if (!cfg80211_chandef_compatible(&new_vht_chandef, 173 &csa_ie->chandef)) { 174 sdata_info(sdata, 175 "BSS %pM: CSA has inconsistent channel data, disconnecting\n", 176 bssid); 177 return -EINVAL; 178 } 179 csa_ie->chandef = new_vht_chandef; 180 } 181 182 return 0; 183 } 184 185 static void ieee80211_send_refuse_measurement_request(struct ieee80211_sub_if_data *sdata, 186 struct ieee80211_msrment_ie *request_ie, 187 const u8 *da, const u8 *bssid, 188 u8 dialog_token) 189 { 190 struct ieee80211_local *local = sdata->local; 191 struct sk_buff *skb; 192 struct ieee80211_mgmt *msr_report; 193 194 skb = dev_alloc_skb(sizeof(*msr_report) + local->hw.extra_tx_headroom + 195 sizeof(struct ieee80211_msrment_ie)); 196 if (!skb) 197 return; 198 199 skb_reserve(skb, local->hw.extra_tx_headroom); 200 msr_report = (struct ieee80211_mgmt *)skb_put(skb, 24); 201 memset(msr_report, 0, 24); 202 memcpy(msr_report->da, da, ETH_ALEN); 203 memcpy(msr_report->sa, sdata->vif.addr, ETH_ALEN); 204 memcpy(msr_report->bssid, bssid, ETH_ALEN); 205 msr_report->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 206 IEEE80211_STYPE_ACTION); 207 208 skb_put(skb, 1 + sizeof(msr_report->u.action.u.measurement)); 209 msr_report->u.action.category = WLAN_CATEGORY_SPECTRUM_MGMT; 210 msr_report->u.action.u.measurement.action_code = 211 WLAN_ACTION_SPCT_MSR_RPRT; 212 msr_report->u.action.u.measurement.dialog_token = dialog_token; 213 214 msr_report->u.action.u.measurement.element_id = WLAN_EID_MEASURE_REPORT; 215 msr_report->u.action.u.measurement.length = 216 sizeof(struct ieee80211_msrment_ie); 217 218 memset(&msr_report->u.action.u.measurement.msr_elem, 0, 219 sizeof(struct ieee80211_msrment_ie)); 220 msr_report->u.action.u.measurement.msr_elem.token = request_ie->token; 221 msr_report->u.action.u.measurement.msr_elem.mode |= 222 IEEE80211_SPCT_MSR_RPRT_MODE_REFUSED; 223 msr_report->u.action.u.measurement.msr_elem.type = request_ie->type; 224 225 ieee80211_tx_skb(sdata, skb); 226 } 227 228 void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata, 229 struct ieee80211_mgmt *mgmt, 230 size_t len) 231 { 232 /* 233 * Ignoring measurement request is spec violation. 234 * Mandatory measurements must be reported optional 235 * measurements might be refused or reported incapable 236 * For now just refuse 237 * TODO: Answer basic measurement as unmeasured 238 */ 239 ieee80211_send_refuse_measurement_request(sdata, 240 &mgmt->u.action.u.measurement.msr_elem, 241 mgmt->sa, mgmt->bssid, 242 mgmt->u.action.u.measurement.dialog_token); 243 } 244