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 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 (sec_chan_offs) { 95 secondary_channel_offset = sec_chan_offs->sec_chan_offs; 96 } else if (!(sta_flags & IEEE80211_STA_DISABLE_HT)) { 97 /* If the secondary channel offset IE is not present, 98 * we can't know what's the post-CSA offset, so the 99 * best we can do is use 20MHz. 100 */ 101 secondary_channel_offset = IEEE80211_HT_PARAM_CHA_SEC_NONE; 102 } 103 104 switch (secondary_channel_offset) { 105 default: 106 /* secondary_channel_offset was present but is invalid */ 107 case IEEE80211_HT_PARAM_CHA_SEC_NONE: 108 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 109 NL80211_CHAN_HT20); 110 break; 111 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: 112 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 113 NL80211_CHAN_HT40PLUS); 114 break; 115 case IEEE80211_HT_PARAM_CHA_SEC_BELOW: 116 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 117 NL80211_CHAN_HT40MINUS); 118 break; 119 case -1: 120 cfg80211_chandef_create(&csa_ie->chandef, new_chan, 121 NL80211_CHAN_NO_HT); 122 /* keep width for 5/10 MHz channels */ 123 switch (sdata->vif.bss_conf.chandef.width) { 124 case NL80211_CHAN_WIDTH_5: 125 case NL80211_CHAN_WIDTH_10: 126 csa_ie->chandef.width = 127 sdata->vif.bss_conf.chandef.width; 128 break; 129 default: 130 break; 131 } 132 break; 133 } 134 135 if (wide_bw_chansw_ie) { 136 new_vht_chandef.chan = new_chan; 137 new_vht_chandef.center_freq1 = 138 ieee80211_channel_to_frequency( 139 wide_bw_chansw_ie->new_center_freq_seg0, 140 new_band); 141 142 switch (wide_bw_chansw_ie->new_channel_width) { 143 default: 144 /* hmmm, ignore VHT and use HT if present */ 145 case IEEE80211_VHT_CHANWIDTH_USE_HT: 146 new_vht_chandef.chan = NULL; 147 break; 148 case IEEE80211_VHT_CHANWIDTH_80MHZ: 149 new_vht_chandef.width = NL80211_CHAN_WIDTH_80; 150 break; 151 case IEEE80211_VHT_CHANWIDTH_160MHZ: 152 new_vht_chandef.width = NL80211_CHAN_WIDTH_160; 153 break; 154 case IEEE80211_VHT_CHANWIDTH_80P80MHZ: 155 /* field is otherwise reserved */ 156 new_vht_chandef.center_freq2 = 157 ieee80211_channel_to_frequency( 158 wide_bw_chansw_ie->new_center_freq_seg1, 159 new_band); 160 new_vht_chandef.width = NL80211_CHAN_WIDTH_80P80; 161 break; 162 } 163 if (sta_flags & IEEE80211_STA_DISABLE_80P80MHZ && 164 new_vht_chandef.width == NL80211_CHAN_WIDTH_80P80) 165 ieee80211_chandef_downgrade(&new_vht_chandef); 166 if (sta_flags & IEEE80211_STA_DISABLE_160MHZ && 167 new_vht_chandef.width == NL80211_CHAN_WIDTH_160) 168 ieee80211_chandef_downgrade(&new_vht_chandef); 169 if (sta_flags & IEEE80211_STA_DISABLE_40MHZ && 170 new_vht_chandef.width > NL80211_CHAN_WIDTH_20) 171 ieee80211_chandef_downgrade(&new_vht_chandef); 172 } 173 174 /* if VHT data is there validate & use it */ 175 if (new_vht_chandef.chan) { 176 if (!cfg80211_chandef_compatible(&new_vht_chandef, 177 &csa_ie->chandef)) { 178 sdata_info(sdata, 179 "BSS %pM: CSA has inconsistent channel data, disconnecting\n", 180 bssid); 181 return -EINVAL; 182 } 183 csa_ie->chandef = new_vht_chandef; 184 } 185 186 return 0; 187 } 188 189 static void ieee80211_send_refuse_measurement_request(struct ieee80211_sub_if_data *sdata, 190 struct ieee80211_msrment_ie *request_ie, 191 const u8 *da, const u8 *bssid, 192 u8 dialog_token) 193 { 194 struct ieee80211_local *local = sdata->local; 195 struct sk_buff *skb; 196 struct ieee80211_mgmt *msr_report; 197 198 skb = dev_alloc_skb(sizeof(*msr_report) + local->hw.extra_tx_headroom + 199 sizeof(struct ieee80211_msrment_ie)); 200 if (!skb) 201 return; 202 203 skb_reserve(skb, local->hw.extra_tx_headroom); 204 msr_report = (struct ieee80211_mgmt *)skb_put(skb, 24); 205 memset(msr_report, 0, 24); 206 memcpy(msr_report->da, da, ETH_ALEN); 207 memcpy(msr_report->sa, sdata->vif.addr, ETH_ALEN); 208 memcpy(msr_report->bssid, bssid, ETH_ALEN); 209 msr_report->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 210 IEEE80211_STYPE_ACTION); 211 212 skb_put(skb, 1 + sizeof(msr_report->u.action.u.measurement)); 213 msr_report->u.action.category = WLAN_CATEGORY_SPECTRUM_MGMT; 214 msr_report->u.action.u.measurement.action_code = 215 WLAN_ACTION_SPCT_MSR_RPRT; 216 msr_report->u.action.u.measurement.dialog_token = dialog_token; 217 218 msr_report->u.action.u.measurement.element_id = WLAN_EID_MEASURE_REPORT; 219 msr_report->u.action.u.measurement.length = 220 sizeof(struct ieee80211_msrment_ie); 221 222 memset(&msr_report->u.action.u.measurement.msr_elem, 0, 223 sizeof(struct ieee80211_msrment_ie)); 224 msr_report->u.action.u.measurement.msr_elem.token = request_ie->token; 225 msr_report->u.action.u.measurement.msr_elem.mode |= 226 IEEE80211_SPCT_MSR_RPRT_MODE_REFUSED; 227 msr_report->u.action.u.measurement.msr_elem.type = request_ie->type; 228 229 ieee80211_tx_skb(sdata, skb); 230 } 231 232 void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata, 233 struct ieee80211_mgmt *mgmt, 234 size_t len) 235 { 236 /* 237 * Ignoring measurement request is spec violation. 238 * Mandatory measurements must be reported optional 239 * measurements might be refused or reported incapable 240 * For now just refuse 241 * TODO: Answer basic measurement as unmeasured 242 */ 243 ieee80211_send_refuse_measurement_request(sdata, 244 &mgmt->u.action.u.measurement.msr_elem, 245 mgmt->sa, mgmt->bssid, 246 mgmt->u.action.u.measurement.dialog_token); 247 } 248