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      1 /*
      2  * Operating classes
      3  * Copyright(c) 2015 Intel Deutschland GmbH
      4  * Contact Information:
      5  * Intel Linux Wireless <ilw (at) linux.intel.com>
      6  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
      7  *
      8  * This software may be distributed under the terms of the BSD license.
      9  * See README for more details.
     10  */
     11 
     12 #include "utils/includes.h"
     13 
     14 #include "utils/common.h"
     15 #include "common/ieee802_11_common.h"
     16 #include "wpa_supplicant_i.h"
     17 #include "bss.h"
     18 
     19 
     20 static enum chan_allowed allow_channel(struct hostapd_hw_modes *mode,
     21 				       u8 op_class, u8 chan,
     22 				       unsigned int *flags)
     23 {
     24 	int i;
     25 	bool is_6ghz = is_6ghz_op_class(op_class);
     26 
     27 	for (i = 0; i < mode->num_channels; i++) {
     28 		bool chan_is_6ghz;
     29 
     30 		chan_is_6ghz = is_6ghz_freq(mode->channels[i].freq);
     31 		if (is_6ghz == chan_is_6ghz && mode->channels[i].chan == chan)
     32 			break;
     33 	}
     34 
     35 	if (i == mode->num_channels ||
     36 	    (mode->channels[i].flag & HOSTAPD_CHAN_DISABLED))
     37 		return NOT_ALLOWED;
     38 
     39 	if (flags)
     40 		*flags = mode->channels[i].flag;
     41 
     42 	if (mode->channels[i].flag & HOSTAPD_CHAN_NO_IR)
     43 		return NO_IR;
     44 
     45 	return ALLOWED;
     46 }
     47 
     48 
     49 static int get_center_80mhz(struct hostapd_hw_modes *mode, u8 channel,
     50 			    const u8 *center_channels, size_t num_chan)
     51 {
     52 	size_t i;
     53 
     54 	if (mode->mode != HOSTAPD_MODE_IEEE80211A)
     55 		return 0;
     56 
     57 	for (i = 0; i < num_chan; i++) {
     58 		/*
     59 		 * In 80 MHz, the bandwidth "spans" 12 channels (e.g., 36-48),
     60 		 * so the center channel is 6 channels away from the start/end.
     61 		 */
     62 		if (channel >= center_channels[i] - 6 &&
     63 		    channel <= center_channels[i] + 6)
     64 			return center_channels[i];
     65 	}
     66 
     67 	return 0;
     68 }
     69 
     70 
     71 static enum chan_allowed verify_80mhz(struct hostapd_hw_modes *mode,
     72 				      u8 op_class, u8 channel)
     73 {
     74 	u8 center_chan;
     75 	unsigned int i;
     76 	unsigned int no_ir = 0;
     77 	const u8 *center_channels;
     78 	size_t num_chan;
     79 	const u8 center_channels_5ghz[] = { 42, 58, 106, 122, 138, 155, 171 };
     80 	const u8 center_channels_6ghz[] = { 7, 23, 39, 55, 71, 87, 103, 119,
     81 					    135, 151, 167, 183, 199, 215 };
     82 
     83 	if (is_6ghz_op_class(op_class)) {
     84 		center_channels = center_channels_6ghz;
     85 		num_chan = ARRAY_SIZE(center_channels_6ghz);
     86 	} else {
     87 		center_channels = center_channels_5ghz;
     88 		num_chan = ARRAY_SIZE(center_channels_5ghz);
     89 	}
     90 
     91 	center_chan = get_center_80mhz(mode, channel, center_channels,
     92 				       num_chan);
     93 	if (!center_chan)
     94 		return NOT_ALLOWED;
     95 
     96 	/* check all the channels are available */
     97 	for (i = 0; i < 4; i++) {
     98 		unsigned int flags;
     99 		u8 adj_chan = center_chan - 6 + i * 4;
    100 
    101 		if (allow_channel(mode, op_class, adj_chan, &flags) ==
    102 		    NOT_ALLOWED)
    103 			return NOT_ALLOWED;
    104 
    105 		if (!(flags & HOSTAPD_CHAN_VHT_80MHZ_SUBCHANNEL))
    106 			return NOT_ALLOWED;
    107 
    108 		if (flags & HOSTAPD_CHAN_NO_IR)
    109 			no_ir = 1;
    110 	}
    111 
    112 	if (no_ir)
    113 		return NO_IR;
    114 
    115 	return ALLOWED;
    116 }
    117 
    118 
    119 static int get_center_160mhz(struct hostapd_hw_modes *mode, u8 channel,
    120 			     const u8 *center_channels, size_t num_chan)
    121 {
    122 	unsigned int i;
    123 
    124 	if (mode->mode != HOSTAPD_MODE_IEEE80211A)
    125 		return 0;
    126 
    127 	for (i = 0; i < num_chan; i++) {
    128 		/*
    129 		 * In 160 MHz, the bandwidth "spans" 28 channels (e.g., 36-64),
    130 		 * so the center channel is 14 channels away from the start/end.
    131 		 */
    132 		if (channel >= center_channels[i] - 14 &&
    133 		    channel <= center_channels[i] + 14)
    134 			return center_channels[i];
    135 	}
    136 
    137 	return 0;
    138 }
    139 
    140 
    141 static enum chan_allowed verify_160mhz(struct hostapd_hw_modes *mode,
    142 				       u8 op_class, u8 channel)
    143 {
    144 	u8 center_chan;
    145 	unsigned int i;
    146 	unsigned int no_ir = 0;
    147 	const u8 *center_channels;
    148 	size_t num_chan;
    149 	const u8 center_channels_5ghz[] = { 50, 114, 163 };
    150 	const u8 center_channels_6ghz[] = { 15, 47, 79, 111, 143, 175, 207 };
    151 
    152 	if (is_6ghz_op_class(op_class)) {
    153 		center_channels = center_channels_6ghz;
    154 		num_chan = ARRAY_SIZE(center_channels_6ghz);
    155 	} else {
    156 		center_channels = center_channels_5ghz;
    157 		num_chan = ARRAY_SIZE(center_channels_5ghz);
    158 	}
    159 
    160 	center_chan = get_center_160mhz(mode, channel, center_channels,
    161 					num_chan);
    162 	if (!center_chan)
    163 		return NOT_ALLOWED;
    164 
    165 	/* Check all the channels are available */
    166 	for (i = 0; i < 8; i++) {
    167 		unsigned int flags;
    168 		u8 adj_chan = center_chan - 14 + i * 4;
    169 
    170 		if (allow_channel(mode, op_class, adj_chan, &flags) ==
    171 		    NOT_ALLOWED)
    172 			return NOT_ALLOWED;
    173 
    174 		if (!(flags & HOSTAPD_CHAN_VHT_80MHZ_SUBCHANNEL) ||
    175 		    !(flags & HOSTAPD_CHAN_VHT_160MHZ_SUBCHANNEL))
    176 			return NOT_ALLOWED;
    177 
    178 		if (flags & HOSTAPD_CHAN_NO_IR)
    179 			no_ir = 1;
    180 	}
    181 
    182 	if (no_ir)
    183 		return NO_IR;
    184 
    185 	return ALLOWED;
    186 }
    187 
    188 
    189 static int get_center_320mhz(struct hostapd_hw_modes *mode, u8 channel,
    190 			     const u8 *center_channels, size_t num_chan)
    191 {
    192 	unsigned int i;
    193 
    194 	if (mode->mode != HOSTAPD_MODE_IEEE80211A || !mode->is_6ghz)
    195 		return 0;
    196 
    197 	for (i = 0; i < num_chan; i++) {
    198 		/*
    199 		* In 320 MHz, the bandwidth "spans" 60 channels (e.g., 65-125),
    200 		* so the center channel is 30 channels away from the start/end.
    201 		*/
    202 		if (channel >= center_channels[i] - 30 &&
    203 		    channel <= center_channels[i] + 30)
    204 			return center_channels[i];
    205 	}
    206 
    207 	return 0;
    208 }
    209 
    210 
    211 static enum chan_allowed verify_320mhz(struct hostapd_hw_modes *mode,
    212 				       u8 op_class, u8 channel)
    213 {
    214 	u8 center_chan;
    215 	unsigned int i;
    216 	bool no_ir = false;
    217 	const u8 *center_channels;
    218 	size_t num_chan;
    219 	const u8 center_channels_6ghz[] = { 31, 63, 95, 127, 159, 191 };
    220 
    221 	center_channels = center_channels_6ghz;
    222 	num_chan = ARRAY_SIZE(center_channels_6ghz);
    223 
    224 	center_chan = get_center_320mhz(mode, channel, center_channels,
    225 					num_chan);
    226 	if (!center_chan)
    227 		return NOT_ALLOWED;
    228 
    229 	/* Check all the channels are available */
    230 	for (i = 0; i < 16; i++) {
    231 		unsigned int flags;
    232 		u8 adj_chan = center_chan - 30 + i * 4;
    233 
    234 		if (allow_channel(mode, op_class, adj_chan, &flags) ==
    235 		    NOT_ALLOWED)
    236 			return NOT_ALLOWED;
    237 
    238 		if (!(flags & HOSTAPD_CHAN_EHT_320MHZ_SUBCHANNEL))
    239 			return NOT_ALLOWED;
    240 
    241 		if (flags & HOSTAPD_CHAN_NO_IR)
    242 			no_ir = true;
    243 	}
    244 
    245 	if (no_ir)
    246 		return NO_IR;
    247 
    248 	return ALLOWED;
    249 }
    250 
    251 
    252 enum chan_allowed verify_channel(struct hostapd_hw_modes *mode, u8 op_class,
    253 				 u8 channel, u8 bw)
    254 {
    255 	unsigned int flag = 0;
    256 	enum chan_allowed res, res2;
    257 
    258 	res2 = res = allow_channel(mode, op_class, channel, &flag);
    259 	if (bw == BW40MINUS || (bw == BW40 && (((channel - 1) / 4) % 2))) {
    260 		if (!(flag & HOSTAPD_CHAN_HT40MINUS))
    261 			return NOT_ALLOWED;
    262 		res2 = allow_channel(mode, op_class, channel - 4, NULL);
    263 	} else if (bw == BW40PLUS) {
    264 		if (!(flag & HOSTAPD_CHAN_HT40PLUS))
    265 			return NOT_ALLOWED;
    266 		res2 = allow_channel(mode, op_class, channel + 4, NULL);
    267 	} else if (is_6ghz_op_class(op_class) && bw == BW40) {
    268 		if (get_6ghz_sec_channel(channel) < 0)
    269 			res2 = allow_channel(mode, op_class, channel - 4, NULL);
    270 		else
    271 			res2 = allow_channel(mode, op_class, channel + 4, NULL);
    272 	} else if (bw == BW80) {
    273 		/*
    274 		 * channel is a center channel and as such, not necessarily a
    275 		 * valid 20 MHz channels. Override earlier allow_channel()
    276 		 * result and use only the 80 MHz specific version.
    277 		 */
    278 		res2 = res = verify_80mhz(mode, op_class, channel);
    279 	} else if (bw == BW160) {
    280 		/*
    281 		 * channel is a center channel and as such, not necessarily a
    282 		 * valid 20 MHz channels. Override earlier allow_channel()
    283 		 * result and use only the 160 MHz specific version.
    284 		 */
    285 		res2 = res = verify_160mhz(mode, op_class, channel);
    286 	} else if (bw == BW80P80) {
    287 		/*
    288 		 * channel is a center channel and as such, not necessarily a
    289 		 * valid 20 MHz channels. Override earlier allow_channel()
    290 		 * result and use only the 80 MHz specific version.
    291 		 */
    292 		res2 = res = verify_80mhz(mode, op_class, channel);
    293 	} else if (bw == BW320) {
    294 		/*
    295 		 * channel is a center channel and as such, not necessarily a
    296 		 * valid 20 MHz channels. Override earlier allow_channel()
    297 		 * result and use only the 320 MHz specific version.
    298 		 */
    299 		res2= res = verify_320mhz(mode, op_class, channel);
    300 	}
    301 
    302 	if (res == NOT_ALLOWED || res2 == NOT_ALLOWED)
    303 		return NOT_ALLOWED;
    304 
    305 	if (res == NO_IR || res2 == NO_IR)
    306 		return NO_IR;
    307 
    308 	return ALLOWED;
    309 }
    310 
    311 
    312 static int wpas_op_class_supported(struct wpa_supplicant *wpa_s,
    313 				   struct wpa_ssid *ssid,
    314 				   const struct oper_class_map *op_class)
    315 {
    316 	int chan;
    317 	size_t i;
    318 	struct hostapd_hw_modes *mode;
    319 	int found;
    320 	int z;
    321 	int freq2 = 0;
    322 	int freq5 = 0;
    323 	bool freq6 = false;
    324 
    325 	mode = get_mode(wpa_s->hw.modes, wpa_s->hw.num_modes, op_class->mode,
    326 			is_6ghz_op_class(op_class->op_class));
    327 	if (!mode)
    328 		return 0;
    329 
    330 	/* If we are configured to disable certain things, take that into
    331 	 * account here. */
    332 	if (ssid && ssid->freq_list && ssid->freq_list[0]) {
    333 		for (z = 0; ; z++) {
    334 			int f = ssid->freq_list[z];
    335 
    336 			if (f == 0)
    337 				break; /* end of list */
    338 			if (is_6ghz_freq(f))
    339 				freq6 = true;
    340 			else if (f > 4000 && f < 6000)
    341 				freq5 = 1;
    342 			else if (f > 2400 && f < 2500)
    343 				freq2 = 1;
    344 		}
    345 	} else {
    346 		/* No frequencies specified, can use anything hardware supports.
    347 		 */
    348 		freq2 = freq5 = 1;
    349 		freq6 = true;
    350 	}
    351 
    352 	if (is_6ghz_op_class(op_class->op_class) && !freq6)
    353 		return 0;
    354 	if (op_class->op_class >= 115 && op_class->op_class <= 130 && !freq5)
    355 		return 0;
    356 	if (op_class->op_class >= 81 && op_class->op_class <= 84 && !freq2)
    357 		return 0;
    358 
    359 #ifdef CONFIG_HT_OVERRIDES
    360 	if (ssid && ssid->disable_ht) {
    361 		switch (op_class->op_class) {
    362 		case 83:
    363 		case 84:
    364 		case 104:
    365 		case 105:
    366 		case 116:
    367 		case 117:
    368 		case 119:
    369 		case 120:
    370 		case 122:
    371 		case 123:
    372 		case 126:
    373 		case 127:
    374 		case 128:
    375 		case 129:
    376 		case 130:
    377 			/* Disable >= 40 MHz channels if HT is disabled */
    378 			return 0;
    379 		}
    380 	}
    381 #endif /* CONFIG_HT_OVERRIDES */
    382 
    383 #ifdef CONFIG_VHT_OVERRIDES
    384 	if (ssid && ssid->disable_vht) {
    385 		if (op_class->op_class >= 128 && op_class->op_class <= 130) {
    386 			/* Disable >= 80 MHz channels if VHT is disabled */
    387 			return 0;
    388 		}
    389 	}
    390 #endif /* CONFIG_VHT_OVERRIDES */
    391 
    392 	if (op_class->op_class == 128) {
    393 		u8 channels[] = { 42, 58, 106, 122, 138, 155, 171 };
    394 
    395 		for (i = 0; i < ARRAY_SIZE(channels); i++) {
    396 			if (verify_channel(mode, op_class->op_class,
    397 					   channels[i], op_class->bw) !=
    398 			    NOT_ALLOWED)
    399 				return 1;
    400 		}
    401 
    402 		return 0;
    403 	}
    404 
    405 	if (op_class->op_class == 129) {
    406 		/* Check if either 160 MHz channels is allowed */
    407 		return verify_channel(mode, op_class->op_class, 50,
    408 				      op_class->bw) != NOT_ALLOWED ||
    409 			verify_channel(mode, op_class->op_class, 114,
    410 				       op_class->bw) != NOT_ALLOWED ||
    411 			verify_channel(mode, op_class->op_class, 163,
    412 				       op_class->bw) != NOT_ALLOWED;
    413 	}
    414 
    415 	if (op_class->op_class == 130) {
    416 		/* Need at least two non-contiguous 80 MHz segments */
    417 		found = 0;
    418 
    419 		if (verify_channel(mode, op_class->op_class, 42,
    420 				   op_class->bw) != NOT_ALLOWED ||
    421 		    verify_channel(mode, op_class->op_class, 58,
    422 				   op_class->bw) != NOT_ALLOWED)
    423 			found++;
    424 		if (verify_channel(mode, op_class->op_class, 106,
    425 				   op_class->bw) != NOT_ALLOWED ||
    426 		    verify_channel(mode, op_class->op_class, 122,
    427 				   op_class->bw) != NOT_ALLOWED ||
    428 		    verify_channel(mode, op_class->op_class, 138,
    429 				   op_class->bw) != NOT_ALLOWED ||
    430 		    verify_channel(mode, op_class->op_class, 155,
    431 				   op_class->bw) != NOT_ALLOWED ||
    432 		    verify_channel(mode, op_class->op_class, 171,
    433 				   op_class->bw) != NOT_ALLOWED)
    434 			found++;
    435 		if (verify_channel(mode, op_class->op_class, 106,
    436 				   op_class->bw) != NOT_ALLOWED &&
    437 		    verify_channel(mode, op_class->op_class, 138,
    438 				   op_class->bw) != NOT_ALLOWED)
    439 			found++;
    440 		if (verify_channel(mode, op_class->op_class, 122,
    441 				   op_class->bw) != NOT_ALLOWED &&
    442 		    verify_channel(mode, op_class->op_class, 155,
    443 				   op_class->bw) != NOT_ALLOWED)
    444 			found++;
    445 		if (verify_channel(mode, op_class->op_class, 138,
    446 				   op_class->bw) != NOT_ALLOWED &&
    447 		    verify_channel(mode, op_class->op_class, 171,
    448 				   op_class->bw) != NOT_ALLOWED)
    449 			found++;
    450 
    451 		if (found >= 2)
    452 			return 1;
    453 
    454 		return 0;
    455 	}
    456 
    457 	if (op_class->op_class == 135) {
    458 		/* Need at least two 80 MHz segments which do not fall under the
    459 		 * same 160 MHz segment to support 80+80 in 6 GHz.
    460 		 */
    461 		int first_seg = 0;
    462 		int curr_seg = 0;
    463 
    464 		for (chan = op_class->min_chan; chan <= op_class->max_chan;
    465 		     chan += op_class->inc) {
    466 			curr_seg++;
    467 			if (verify_channel(mode, op_class->op_class, chan,
    468 					   op_class->bw) != NOT_ALLOWED) {
    469 				if (!first_seg) {
    470 					first_seg = curr_seg;
    471 					continue;
    472 				}
    473 
    474 				/* Supported if at least two non-consecutive 80
    475 				 * MHz segments allowed.
    476 				 */
    477 				if ((curr_seg - first_seg) > 1)
    478 					return 1;
    479 
    480 				/* Supported even if the 80 MHz segments are
    481 				 * consecutive when they do not fall under the
    482 				 * same 160 MHz segment.
    483 				 */
    484 				if ((first_seg % 2) == 0)
    485 					return 1;
    486 			}
    487 		}
    488 
    489 		return 0;
    490 	}
    491 
    492 	found = 0;
    493 	for (chan = op_class->min_chan; chan <= op_class->max_chan;
    494 	     chan += op_class->inc) {
    495 		if (verify_channel(mode, op_class->op_class, chan,
    496 				   op_class->bw) != NOT_ALLOWED) {
    497 			found = 1;
    498 			break;
    499 		}
    500 	}
    501 
    502 	return found;
    503 }
    504 
    505 
    506 static int wpas_sta_secondary_channel_offset(struct wpa_bss *bss, u8 *current,
    507 					     u8 *channel)
    508 {
    509 
    510 	const u8 *ies;
    511 	u8 phy_type;
    512 	size_t ies_len;
    513 
    514 	if (!bss)
    515 		return -1;
    516 	ies = wpa_bss_ie_ptr(bss);
    517 	ies_len = bss->ie_len ? bss->ie_len : bss->beacon_ie_len;
    518 	return wpas_get_op_chan_phy(bss->freq, ies, ies_len, current,
    519 				    channel, &phy_type);
    520 }
    521 
    522 
    523 size_t wpas_supp_op_class_ie(struct wpa_supplicant *wpa_s,
    524 			     struct wpa_ssid *ssid,
    525 			     struct wpa_bss *bss, u8 *pos, size_t len)
    526 {
    527 	struct wpabuf *buf;
    528 	u8 op, current, chan;
    529 	u8 *ie_len;
    530 	size_t res;
    531 	bool op128 = false, op130 = false, op133 = false, op135 = false;
    532 
    533 	/*
    534 	 * Determine the current operating class correct mode based on
    535 	 * advertised BSS capabilities, if available. Fall back to a less
    536 	 * accurate guess based on frequency if the needed IEs are not available
    537 	 * or used.
    538 	 */
    539 	if (wpas_sta_secondary_channel_offset(bss, &current, &chan) < 0 &&
    540 	    ieee80211_freq_to_channel_ext(bss->freq, 0,
    541 					  CONF_OPER_CHWIDTH_USE_HT, &current,
    542 					  &chan) == NUM_HOSTAPD_MODES)
    543 		return 0;
    544 
    545 	/*
    546 	 * Need 3 bytes for EID, length, and current operating class, plus
    547 	 * 1 byte for every other supported operating class.
    548 	 */
    549 	buf = wpabuf_alloc(global_op_class_size + 3);
    550 	if (!buf)
    551 		return 0;
    552 
    553 	wpabuf_put_u8(buf, WLAN_EID_SUPPORTED_OPERATING_CLASSES);
    554 	/* Will set the length later, putting a placeholder */
    555 	ie_len = wpabuf_put(buf, 1);
    556 	wpabuf_put_u8(buf, current);
    557 
    558 	for (op = 0; global_op_class[op].op_class; op++) {
    559 		bool supp;
    560 		u8 op_class = global_op_class[op].op_class;
    561 
    562 		supp = wpas_op_class_supported(wpa_s, ssid,
    563 					       &global_op_class[op]);
    564 		if (!supp)
    565 			continue;
    566 		switch (op_class) {
    567 		case 128:
    568 			op128 = true;
    569 			break;
    570 		case 130:
    571 			op130 = true;
    572 			break;
    573 		case 133:
    574 			op133 = true;
    575 			break;
    576 		case 135:
    577 			op135 = true;
    578 			break;
    579 		}
    580 		if (is_80plus_op_class(op_class))
    581 			continue;
    582 
    583 		/* Add a 1-octet operating class to the Operating Class field */
    584 		wpabuf_put_u8(buf, global_op_class[op].op_class);
    585 	}
    586 
    587 	/* Add the 2-octet operating classes (i.e., 80+80 MHz cases), if any */
    588 	if ((op128 && op130) || (op133 && op135)) {
    589 		/* Operating Class Duple Sequence field */
    590 
    591 		/* Zero Delimiter */
    592 		wpabuf_put_u8(buf, 0);
    593 
    594 		/* Operating Class Duple List */
    595 		if (op128 && op130) {
    596 			wpabuf_put_u8(buf, 130);
    597 			wpabuf_put_u8(buf, 128);
    598 		}
    599 		if (op133 && op135) {
    600 			wpabuf_put_u8(buf, 135);
    601 			wpabuf_put_u8(buf, 133);
    602 		}
    603 	}
    604 
    605 	*ie_len = wpabuf_len(buf) - 2;
    606 	if (*ie_len < 2) {
    607 		wpa_printf(MSG_DEBUG,
    608 			   "No supported operating classes IE to add");
    609 		res = 0;
    610 	} else if (wpabuf_len(buf) > len) {
    611 		wpa_printf(MSG_ERROR,
    612 			   "Supported operating classes IE exceeds maximum buffer length");
    613 		res = 0;
    614 	} else {
    615 		os_memcpy(pos, wpabuf_head(buf), wpabuf_len(buf));
    616 		res = wpabuf_len(buf);
    617 		wpa_hexdump_buf(MSG_DEBUG,
    618 				"Added supported operating classes IE", buf);
    619 	}
    620 
    621 	wpabuf_free(buf);
    622 	return res;
    623 }
    624 
    625 
    626 int * wpas_supp_op_classes(struct wpa_supplicant *wpa_s)
    627 {
    628 	int op;
    629 	unsigned int pos, max_num = 0;
    630 	int *classes;
    631 
    632 	for (op = 0; global_op_class[op].op_class; op++)
    633 		max_num++;
    634 	classes = os_zalloc((max_num + 1) * sizeof(int));
    635 	if (!classes)
    636 		return NULL;
    637 
    638 	for (op = 0, pos = 0; global_op_class[op].op_class; op++) {
    639 		if (wpas_op_class_supported(wpa_s, NULL, &global_op_class[op]))
    640 			classes[pos++] = global_op_class[op].op_class;
    641 	}
    642 
    643 	return classes;
    644 }
    645