1/*
2 * hostapd / IEEE 802.11ac VHT
3 * Copyright (c) 2002-2009, Jouni Malinen <j@w1.fi>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of BSD license
7 *
8 * See README and COPYING for more details.
9 */
10
11#include "utils/includes.h"
12
13#include "utils/common.h"
14#include "common/ieee802_11_defs.h"
15#include "hostapd.h"
16#include "ap_config.h"
17#include "sta_info.h"
18#include "beacon.h"
19#include "ieee802_11.h"
20#include "dfs.h"
21
22
23u8 * hostapd_eid_vht_capabilities(struct hostapd_data *hapd, u8 *eid, u32 nsts)
24{
25	struct ieee80211_vht_capabilities *cap;
26	struct hostapd_hw_modes *mode = hapd->iface->current_mode;
27	u8 *pos = eid;
28
29	if (!mode)
30		return eid;
31
32	if (mode->mode == HOSTAPD_MODE_IEEE80211G && hapd->conf->vendor_vht &&
33	    mode->vht_capab == 0 && hapd->iface->hw_features) {
34		int i;
35
36		for (i = 0; i < hapd->iface->num_hw_features; i++) {
37			if (hapd->iface->hw_features[i].mode ==
38			    HOSTAPD_MODE_IEEE80211A) {
39				mode = &hapd->iface->hw_features[i];
40				break;
41			}
42		}
43	}
44
45	*pos++ = WLAN_EID_VHT_CAP;
46	*pos++ = sizeof(*cap);
47
48	cap = (struct ieee80211_vht_capabilities *) pos;
49	os_memset(cap, 0, sizeof(*cap));
50	cap->vht_capabilities_info = host_to_le32(
51		hapd->iface->conf->vht_capab);
52
53	if (nsts != 0) {
54		u32 hapd_nsts;
55
56		hapd_nsts = le_to_host32(cap->vht_capabilities_info);
57		hapd_nsts = (hapd_nsts >> VHT_CAP_BEAMFORMEE_STS_OFFSET) & 7;
58		cap->vht_capabilities_info &=
59			~(host_to_le32(hapd_nsts <<
60				       VHT_CAP_BEAMFORMEE_STS_OFFSET));
61		cap->vht_capabilities_info |=
62			host_to_le32(nsts << VHT_CAP_BEAMFORMEE_STS_OFFSET);
63	}
64
65	/* Supported MCS set comes from hw */
66	os_memcpy(&cap->vht_supported_mcs_set, mode->vht_mcs_set, 8);
67
68	pos += sizeof(*cap);
69
70	return pos;
71}
72
73
74u8 * hostapd_eid_vht_operation(struct hostapd_data *hapd, u8 *eid)
75{
76	struct ieee80211_vht_operation *oper;
77	u8 *pos = eid;
78
79	*pos++ = WLAN_EID_VHT_OPERATION;
80	*pos++ = sizeof(*oper);
81
82	oper = (struct ieee80211_vht_operation *) pos;
83	os_memset(oper, 0, sizeof(*oper));
84
85	/*
86	 * center freq = 5 GHz + (5 * index)
87	 * So index 42 gives center freq 5.210 GHz
88	 * which is channel 42 in 5G band
89	 */
90	oper->vht_op_info_chan_center_freq_seg0_idx =
91		hapd->iconf->vht_oper_centr_freq_seg0_idx;
92	oper->vht_op_info_chan_center_freq_seg1_idx =
93		hapd->iconf->vht_oper_centr_freq_seg1_idx;
94
95	oper->vht_op_info_chwidth = hapd->iconf->vht_oper_chwidth;
96	if (hapd->iconf->vht_oper_chwidth == 2) {
97		/*
98		 * Convert 160 MHz channel width to new style as interop
99		 * workaround.
100		 */
101		oper->vht_op_info_chwidth = 1;
102		oper->vht_op_info_chan_center_freq_seg1_idx =
103			oper->vht_op_info_chan_center_freq_seg0_idx;
104		if (hapd->iconf->channel <
105		    hapd->iconf->vht_oper_centr_freq_seg0_idx)
106			oper->vht_op_info_chan_center_freq_seg0_idx -= 8;
107		else
108			oper->vht_op_info_chan_center_freq_seg0_idx += 8;
109	} else if (hapd->iconf->vht_oper_chwidth == 3) {
110		/*
111		 * Convert 80+80 MHz channel width to new style as interop
112		 * workaround.
113		 */
114		oper->vht_op_info_chwidth = 1;
115	}
116
117	/* VHT Basic MCS set comes from hw */
118	/* Hard code 1 stream, MCS0-7 is a min Basic VHT MCS rates */
119	oper->vht_basic_mcs_set = host_to_le16(0xfffc);
120	pos += sizeof(*oper);
121
122	return pos;
123}
124
125
126static int check_valid_vht_mcs(struct hostapd_hw_modes *mode,
127			       const u8 *sta_vht_capab)
128{
129	const struct ieee80211_vht_capabilities *vht_cap;
130	struct ieee80211_vht_capabilities ap_vht_cap;
131	u16 sta_rx_mcs_set, ap_tx_mcs_set;
132	int i;
133
134	if (!mode)
135		return 1;
136
137	/*
138	 * Disable VHT caps for STAs for which there is not even a single
139	 * allowed MCS in any supported number of streams, i.e., STA is
140	 * advertising 3 (not supported) as VHT MCS rates for all supported
141	 * stream cases.
142	 */
143	os_memcpy(&ap_vht_cap.vht_supported_mcs_set, mode->vht_mcs_set,
144		  sizeof(ap_vht_cap.vht_supported_mcs_set));
145	vht_cap = (const struct ieee80211_vht_capabilities *) sta_vht_capab;
146
147	/* AP Tx MCS map vs. STA Rx MCS map */
148	sta_rx_mcs_set = le_to_host16(vht_cap->vht_supported_mcs_set.rx_map);
149	ap_tx_mcs_set = le_to_host16(ap_vht_cap.vht_supported_mcs_set.tx_map);
150
151	for (i = 0; i < VHT_RX_NSS_MAX_STREAMS; i++) {
152		if ((ap_tx_mcs_set & (0x3 << (i * 2))) == 3)
153			continue;
154
155		if ((sta_rx_mcs_set & (0x3 << (i * 2))) == 3)
156			continue;
157
158		return 1;
159	}
160
161	wpa_printf(MSG_DEBUG,
162		   "No matching VHT MCS found between AP TX and STA RX");
163	return 0;
164}
165
166
167u8 * hostapd_eid_wb_chsw_wrapper(struct hostapd_data *hapd, u8 *eid)
168{
169	u8 bw, chan1, chan2 = 0;
170	int freq1;
171
172	if (!hapd->cs_freq_params.channel ||
173	    !hapd->cs_freq_params.vht_enabled)
174		return eid;
175
176	/* bandwidth: 0: 40, 1: 80, 2: 160, 3: 80+80 */
177	switch (hapd->cs_freq_params.bandwidth) {
178	case 40:
179		bw = 0;
180		break;
181	case 80:
182		/* check if it's 80+80 */
183		if (!hapd->cs_freq_params.center_freq2)
184			bw = 1;
185		else
186			bw = 3;
187		break;
188	case 160:
189		bw = 2;
190		break;
191	default:
192		/* not valid VHT bandwidth or not in CSA */
193		return eid;
194	}
195
196	freq1 = hapd->cs_freq_params.center_freq1 ?
197		hapd->cs_freq_params.center_freq1 :
198		hapd->cs_freq_params.freq;
199	if (ieee80211_freq_to_chan(freq1, &chan1) !=
200	    HOSTAPD_MODE_IEEE80211A)
201		return eid;
202
203	if (hapd->cs_freq_params.center_freq2 &&
204	    ieee80211_freq_to_chan(hapd->cs_freq_params.center_freq2,
205				   &chan2) != HOSTAPD_MODE_IEEE80211A)
206		return eid;
207
208	*eid++ = WLAN_EID_VHT_CHANNEL_SWITCH_WRAPPER;
209	*eid++ = 5; /* Length of Channel Switch Wrapper */
210	*eid++ = WLAN_EID_VHT_WIDE_BW_CHSWITCH;
211	*eid++ = 3; /* Length of Wide Bandwidth Channel Switch element */
212	*eid++ = bw; /* New Channel Width */
213	*eid++ = chan1; /* New Channel Center Frequency Segment 0 */
214	*eid++ = chan2; /* New Channel Center Frequency Segment 1 */
215
216	return eid;
217}
218
219
220u8 * hostapd_eid_txpower_envelope(struct hostapd_data *hapd, u8 *eid)
221{
222	struct hostapd_iface *iface = hapd->iface;
223	struct hostapd_config *iconf = iface->conf;
224	struct hostapd_hw_modes *mode = iface->current_mode;
225	struct hostapd_channel_data *chan;
226	int dfs, i;
227	u8 channel, tx_pwr_count, local_pwr_constraint;
228	int max_tx_power;
229	u8 tx_pwr;
230
231	if (!mode)
232		return eid;
233
234	if (ieee80211_freq_to_chan(iface->freq, &channel) == NUM_HOSTAPD_MODES)
235		return eid;
236
237	for (i = 0; i < mode->num_channels; i++) {
238		if (mode->channels[i].freq == iface->freq)
239			break;
240	}
241	if (i == mode->num_channels)
242		return eid;
243
244	switch (iface->conf->vht_oper_chwidth) {
245	case VHT_CHANWIDTH_USE_HT:
246		if (iconf->secondary_channel == 0) {
247			/* Max Transmit Power count = 0 (20 MHz) */
248			tx_pwr_count = 0;
249		} else {
250			/* Max Transmit Power count = 1 (20, 40 MHz) */
251			tx_pwr_count = 1;
252		}
253		break;
254	case VHT_CHANWIDTH_80MHZ:
255		/* Max Transmit Power count = 2 (20, 40, and 80 MHz) */
256		tx_pwr_count = 2;
257		break;
258	case VHT_CHANWIDTH_80P80MHZ:
259	case VHT_CHANWIDTH_160MHZ:
260		/* Max Transmit Power count = 3 (20, 40, 80, 160/80+80 MHz) */
261		tx_pwr_count = 3;
262		break;
263	default:
264		return eid;
265	}
266
267	/*
268	 * Below local_pwr_constraint logic is referred from
269	 * hostapd_eid_pwr_constraint.
270	 *
271	 * Check if DFS is required by regulatory.
272	 */
273	dfs = hostapd_is_dfs_required(hapd->iface);
274	if (dfs < 0)
275		dfs = 0;
276
277	/*
278	 * In order to meet regulations when TPC is not implemented using
279	 * a transmit power that is below the legal maximum (including any
280	 * mitigation factor) should help. In this case, indicate 3 dB below
281	 * maximum allowed transmit power.
282	 */
283	if (hapd->iconf->local_pwr_constraint == -1)
284		local_pwr_constraint = (dfs == 0) ? 0 : 3;
285	else
286		local_pwr_constraint = hapd->iconf->local_pwr_constraint;
287
288	/*
289	 * A STA that is not an AP shall use a transmit power less than or
290	 * equal to the local maximum transmit power level for the channel.
291	 * The local maximum transmit power can be calculated from the formula:
292	 * local max TX pwr = max TX pwr - local pwr constraint
293	 * Where max TX pwr is maximum transmit power level specified for
294	 * channel in Country element and local pwr constraint is specified
295	 * for channel in this Power Constraint element.
296	 */
297	chan = &mode->channels[i];
298	max_tx_power = chan->max_tx_power - local_pwr_constraint;
299
300	/*
301	 * Local Maximum Transmit power is encoded as two's complement
302	 * with a 0.5 dB step.
303	 */
304	max_tx_power *= 2; /* in 0.5 dB steps */
305	if (max_tx_power > 127) {
306		/* 63.5 has special meaning of 63.5 dBm or higher */
307		max_tx_power = 127;
308	}
309	if (max_tx_power < -128)
310		max_tx_power = -128;
311	if (max_tx_power < 0)
312		tx_pwr = 0x80 + max_tx_power + 128;
313	else
314		tx_pwr = max_tx_power;
315
316	*eid++ = WLAN_EID_VHT_TRANSMIT_POWER_ENVELOPE;
317	*eid++ = 2 + tx_pwr_count;
318
319	/*
320	 * Max Transmit Power count and
321	 * Max Transmit Power units = 0 (EIRP)
322	 */
323	*eid++ = tx_pwr_count;
324
325	for (i = 0; i <= tx_pwr_count; i++)
326		*eid++ = tx_pwr;
327
328	return eid;
329}
330
331
332u16 copy_sta_vht_capab(struct hostapd_data *hapd, struct sta_info *sta,
333		       const u8 *vht_capab)
334{
335	/* Disable VHT caps for STAs associated to no-VHT BSSes. */
336	if (!vht_capab ||
337	    !hapd->iconf->ieee80211ac || hapd->conf->disable_11ac ||
338	    !check_valid_vht_mcs(hapd->iface->current_mode, vht_capab)) {
339		sta->flags &= ~WLAN_STA_VHT;
340		os_free(sta->vht_capabilities);
341		sta->vht_capabilities = NULL;
342		return WLAN_STATUS_SUCCESS;
343	}
344
345	if (sta->vht_capabilities == NULL) {
346		sta->vht_capabilities =
347			os_zalloc(sizeof(struct ieee80211_vht_capabilities));
348		if (sta->vht_capabilities == NULL)
349			return WLAN_STATUS_UNSPECIFIED_FAILURE;
350	}
351
352	sta->flags |= WLAN_STA_VHT;
353	os_memcpy(sta->vht_capabilities, vht_capab,
354		  sizeof(struct ieee80211_vht_capabilities));
355
356	return WLAN_STATUS_SUCCESS;
357}
358
359
360u16 copy_sta_vendor_vht(struct hostapd_data *hapd, struct sta_info *sta,
361			const u8 *ie, size_t len)
362{
363	const u8 *vht_capab;
364	unsigned int vht_capab_len;
365
366	if (!ie || len < 5 + 2 + sizeof(struct ieee80211_vht_capabilities) ||
367	    hapd->conf->disable_11ac)
368		goto no_capab;
369
370	/* The VHT Capabilities element embedded in vendor VHT */
371	vht_capab = ie + 5;
372	if (vht_capab[0] != WLAN_EID_VHT_CAP)
373		goto no_capab;
374	vht_capab_len = vht_capab[1];
375	if (vht_capab_len < sizeof(struct ieee80211_vht_capabilities) ||
376	    (int) vht_capab_len > ie + len - vht_capab - 2)
377		goto no_capab;
378	vht_capab += 2;
379
380	if (sta->vht_capabilities == NULL) {
381		sta->vht_capabilities =
382			os_zalloc(sizeof(struct ieee80211_vht_capabilities));
383		if (sta->vht_capabilities == NULL)
384			return WLAN_STATUS_UNSPECIFIED_FAILURE;
385	}
386
387	sta->flags |= WLAN_STA_VHT | WLAN_STA_VENDOR_VHT;
388	os_memcpy(sta->vht_capabilities, vht_capab,
389		  sizeof(struct ieee80211_vht_capabilities));
390	return WLAN_STATUS_SUCCESS;
391
392no_capab:
393	sta->flags &= ~WLAN_STA_VENDOR_VHT;
394	return WLAN_STATUS_SUCCESS;
395}
396
397
398u8 * hostapd_eid_vendor_vht(struct hostapd_data *hapd, u8 *eid)
399{
400	u8 *pos = eid;
401
402	if (!hapd->iface->current_mode)
403		return eid;
404
405	*pos++ = WLAN_EID_VENDOR_SPECIFIC;
406	*pos++ = (5 +		/* The Vendor OUI, type and subtype */
407		  2 + sizeof(struct ieee80211_vht_capabilities) +
408		  2 + sizeof(struct ieee80211_vht_operation));
409
410	WPA_PUT_BE32(pos, (OUI_BROADCOM << 8) | VENDOR_VHT_TYPE);
411	pos += 4;
412	*pos++ = VENDOR_VHT_SUBTYPE;
413	pos = hostapd_eid_vht_capabilities(hapd, pos, 0);
414	pos = hostapd_eid_vht_operation(hapd, pos);
415
416	return pos;
417}
418
419
420u16 set_sta_vht_opmode(struct hostapd_data *hapd, struct sta_info *sta,
421		       const u8 *vht_oper_notif)
422{
423	if (!vht_oper_notif) {
424		sta->flags &= ~WLAN_STA_VHT_OPMODE_ENABLED;
425		return WLAN_STATUS_SUCCESS;
426	}
427
428	sta->flags |= WLAN_STA_VHT_OPMODE_ENABLED;
429	sta->vht_opmode = *vht_oper_notif;
430	return WLAN_STATUS_SUCCESS;
431}
432
433
434void hostapd_get_vht_capab(struct hostapd_data *hapd,
435			   struct ieee80211_vht_capabilities *vht_cap,
436			   struct ieee80211_vht_capabilities *neg_vht_cap)
437{
438	u32 cap, own_cap, sym_caps;
439
440	if (vht_cap == NULL)
441		return;
442	os_memcpy(neg_vht_cap, vht_cap, sizeof(*neg_vht_cap));
443
444	cap = le_to_host32(neg_vht_cap->vht_capabilities_info);
445	own_cap = hapd->iconf->vht_capab;
446
447	/* mask out symmetric VHT capabilities we don't support */
448	sym_caps = VHT_CAP_SHORT_GI_80 | VHT_CAP_SHORT_GI_160;
449	cap &= ~sym_caps | (own_cap & sym_caps);
450
451	/* mask out beamformer/beamformee caps if not supported */
452	if (!(own_cap & VHT_CAP_SU_BEAMFORMER_CAPABLE))
453		cap &= ~(VHT_CAP_SU_BEAMFORMEE_CAPABLE |
454			 VHT_CAP_BEAMFORMEE_STS_MAX);
455
456	if (!(own_cap & VHT_CAP_SU_BEAMFORMEE_CAPABLE))
457		cap &= ~(VHT_CAP_SU_BEAMFORMER_CAPABLE |
458			 VHT_CAP_SOUNDING_DIMENSION_MAX);
459
460	if (!(own_cap & VHT_CAP_MU_BEAMFORMER_CAPABLE))
461		cap &= ~VHT_CAP_MU_BEAMFORMEE_CAPABLE;
462
463	if (!(own_cap & VHT_CAP_MU_BEAMFORMEE_CAPABLE))
464		cap &= ~VHT_CAP_MU_BEAMFORMER_CAPABLE;
465
466	/* mask channel widths we don't support */
467	switch (own_cap & VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
468	case VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
469		break;
470	case VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
471		if (cap & VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ) {
472			cap &= ~VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ;
473			cap |= VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
474		}
475		break;
476	default:
477		cap &= ~VHT_CAP_SUPP_CHAN_WIDTH_MASK;
478		break;
479	}
480
481	if (!(cap & VHT_CAP_SUPP_CHAN_WIDTH_MASK))
482		cap &= ~VHT_CAP_SHORT_GI_160;
483
484	/*
485	 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps
486	 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps
487	 */
488	if (!(own_cap & VHT_CAP_RXSTBC_MASK))
489		cap &= ~VHT_CAP_TXSTBC;
490	if (!(own_cap & VHT_CAP_TXSTBC))
491		cap &= ~VHT_CAP_RXSTBC_MASK;
492
493	neg_vht_cap->vht_capabilities_info = host_to_le32(cap);
494}
495