1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * spectrum management
4 *
5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
6 * Copyright 2002-2005, Instant802 Networks, Inc.
7 * Copyright 2005-2006, Devicescape Software, Inc.
8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10 * Copyright 2007-2008, Intel Corporation
11 * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
12 * Copyright (C) 2018, 2020, 2022-2023 Intel Corporation
13 */
14
15#include <linux/ieee80211.h>
16#include <net/cfg80211.h>
17#include <net/mac80211.h>
18#include "ieee80211_i.h"
19#include "sta_info.h"
20#include "wme.h"
21
22int ieee80211_parse_ch_switch_ie(struct ieee80211_sub_if_data *sdata,
23 struct ieee802_11_elems *elems,
24 enum nl80211_band current_band,
25 u32 vht_cap_info,
26 ieee80211_conn_flags_t conn_flags, u8 *bssid,
27 struct ieee80211_csa_ie *csa_ie)
28{
29 enum nl80211_band new_band = current_band;
30 int new_freq;
31 u8 new_chan_no;
32 struct ieee80211_channel *new_chan;
33 struct cfg80211_chan_def new_vht_chandef = {};
34 const struct ieee80211_sec_chan_offs_ie *sec_chan_offs;
35 const struct ieee80211_wide_bw_chansw_ie *wide_bw_chansw_ie;
36 const struct ieee80211_bandwidth_indication *bwi;
37 int secondary_channel_offset = -1;
38
39 memset(csa_ie, 0, sizeof(*csa_ie));
40
41 sec_chan_offs = elems->sec_chan_offs;
42 wide_bw_chansw_ie = elems->wide_bw_chansw_ie;
43 bwi = elems->bandwidth_indication;
44
45 if (conn_flags & (IEEE80211_CONN_DISABLE_HT |
46 IEEE80211_CONN_DISABLE_40MHZ)) {
47 sec_chan_offs = NULL;
48 wide_bw_chansw_ie = NULL;
49 }
50
51 if (conn_flags & IEEE80211_CONN_DISABLE_VHT)
52 wide_bw_chansw_ie = NULL;
53
54 if (elems->ext_chansw_ie) {
55 if (!ieee80211_operating_class_to_band(
56 operating_class: elems->ext_chansw_ie->new_operating_class,
57 band: &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(chan: new_chan_no, band: new_band);
88 new_chan = ieee80211_get_channel(wiphy: sdata->local->hw.wiphy, freq: 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 (!(conn_flags & IEEE80211_CONN_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(chandef: &csa_ie->chandef, channel: new_chan,
111 chantype: NL80211_CHAN_HT20);
112 break;
113 case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
114 cfg80211_chandef_create(chandef: &csa_ie->chandef, channel: new_chan,
115 chantype: NL80211_CHAN_HT40PLUS);
116 break;
117 case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
118 cfg80211_chandef_create(chandef: &csa_ie->chandef, channel: new_chan,
119 chantype: NL80211_CHAN_HT40MINUS);
120 break;
121 case -1:
122 cfg80211_chandef_create(chandef: &csa_ie->chandef, channel: new_chan,
123 chantype: 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 (bwi) {
138 /* start with the CSA one */
139 new_vht_chandef = csa_ie->chandef;
140 /* and update the width accordingly */
141 /* FIXME: support 160/320 */
142 ieee80211_chandef_eht_oper(info: &bwi->info, support_160: true, support_320: true,
143 chandef: &new_vht_chandef);
144 } else if (wide_bw_chansw_ie) {
145 u8 new_seg1 = wide_bw_chansw_ie->new_center_freq_seg1;
146 struct ieee80211_vht_operation vht_oper = {
147 .chan_width =
148 wide_bw_chansw_ie->new_channel_width,
149 .center_freq_seg0_idx =
150 wide_bw_chansw_ie->new_center_freq_seg0,
151 .center_freq_seg1_idx = new_seg1,
152 /* .basic_mcs_set doesn't matter */
153 };
154 struct ieee80211_ht_operation ht_oper = {
155 .operation_mode =
156 cpu_to_le16(new_seg1 <<
157 IEEE80211_HT_OP_MODE_CCFS2_SHIFT),
158 };
159
160 /* default, for the case of IEEE80211_VHT_CHANWIDTH_USE_HT,
161 * to the previously parsed chandef
162 */
163 new_vht_chandef = csa_ie->chandef;
164
165 /* ignore if parsing fails */
166 if (!ieee80211_chandef_vht_oper(hw: &sdata->local->hw,
167 vht_cap_info,
168 oper: &vht_oper, htop: &ht_oper,
169 chandef: &new_vht_chandef))
170 new_vht_chandef.chan = NULL;
171
172 if (conn_flags & IEEE80211_CONN_DISABLE_80P80MHZ &&
173 new_vht_chandef.width == NL80211_CHAN_WIDTH_80P80)
174 ieee80211_chandef_downgrade(c: &new_vht_chandef);
175 if (conn_flags & IEEE80211_CONN_DISABLE_160MHZ &&
176 new_vht_chandef.width == NL80211_CHAN_WIDTH_160)
177 ieee80211_chandef_downgrade(c: &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(chandef1: &new_vht_chandef,
183 chandef2: &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 if (elems->max_channel_switch_time)
193 csa_ie->max_switch_time =
194 (elems->max_channel_switch_time[0] << 0) |
195 (elems->max_channel_switch_time[1] << 8) |
196 (elems->max_channel_switch_time[2] << 16);
197
198 return 0;
199}
200
201static void ieee80211_send_refuse_measurement_request(struct ieee80211_sub_if_data *sdata,
202 struct ieee80211_msrment_ie *request_ie,
203 const u8 *da, const u8 *bssid,
204 u8 dialog_token)
205{
206 struct ieee80211_local *local = sdata->local;
207 struct sk_buff *skb;
208 struct ieee80211_mgmt *msr_report;
209
210 skb = dev_alloc_skb(length: sizeof(*msr_report) + local->hw.extra_tx_headroom +
211 sizeof(struct ieee80211_msrment_ie));
212 if (!skb)
213 return;
214
215 skb_reserve(skb, len: local->hw.extra_tx_headroom);
216 msr_report = skb_put_zero(skb, len: 24);
217 memcpy(msr_report->da, da, ETH_ALEN);
218 memcpy(msr_report->sa, sdata->vif.addr, ETH_ALEN);
219 memcpy(msr_report->bssid, bssid, ETH_ALEN);
220 msr_report->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
221 IEEE80211_STYPE_ACTION);
222
223 skb_put(skb, len: 1 + sizeof(msr_report->u.action.u.measurement));
224 msr_report->u.action.category = WLAN_CATEGORY_SPECTRUM_MGMT;
225 msr_report->u.action.u.measurement.action_code =
226 WLAN_ACTION_SPCT_MSR_RPRT;
227 msr_report->u.action.u.measurement.dialog_token = dialog_token;
228
229 msr_report->u.action.u.measurement.element_id = WLAN_EID_MEASURE_REPORT;
230 msr_report->u.action.u.measurement.length =
231 sizeof(struct ieee80211_msrment_ie);
232
233 memset(&msr_report->u.action.u.measurement.msr_elem, 0,
234 sizeof(struct ieee80211_msrment_ie));
235 msr_report->u.action.u.measurement.msr_elem.token = request_ie->token;
236 msr_report->u.action.u.measurement.msr_elem.mode |=
237 IEEE80211_SPCT_MSR_RPRT_MODE_REFUSED;
238 msr_report->u.action.u.measurement.msr_elem.type = request_ie->type;
239
240 ieee80211_tx_skb(sdata, skb);
241}
242
243void ieee80211_process_measurement_req(struct ieee80211_sub_if_data *sdata,
244 struct ieee80211_mgmt *mgmt,
245 size_t len)
246{
247 /*
248 * Ignoring measurement request is spec violation.
249 * Mandatory measurements must be reported optional
250 * measurements might be refused or reported incapable
251 * For now just refuse
252 * TODO: Answer basic measurement as unmeasured
253 */
254 ieee80211_send_refuse_measurement_request(sdata,
255 request_ie: &mgmt->u.action.u.measurement.msr_elem,
256 da: mgmt->sa, bssid: mgmt->bssid,
257 dialog_token: mgmt->u.action.u.measurement.dialog_token);
258}
259

source code of linux/net/mac80211/spectmgmt.c