File: iw_nl80211.c

package info (click to toggle)
wavemon 0.9.1-1
  • links: PTS
  • area: main
  • in suites: bookworm, bullseye, sid, trixie
  • size: 892 kB
  • sloc: ansic: 5,532; sh: 3,062; makefile: 59
file content (730 lines) | stat: -rw-r--r-- 21,967 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
/*
 * FIXME:
 * PROTOTYPE: add nl80211 calls to iw_if. Mostly copied/stolen from iw
 */
#include "wavemon.h"
#include <net/if.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>

#include "iw_nl80211.h"

/**
 * handle_cmd: process @cmd
 * Returns 0 if ok, -errno < 0 on failure
 * stolen/modified from iw:iw.c 
 */
int handle_cmd(struct cmd *cmd)
{
	struct nl_cb *cb;
	struct nl_msg *msg;
	static int nl80211_id = -1;
	int ret;
	uint32_t ifindex, idx;

	/*
	 * Initialization of static components:
	 * - per-cmd socket
	 * - global nl80211 ID
	 * - per-cmd interface index (in case conf_ifname() changes)
	 */
	if (!cmd->sk) {
		cmd->sk = nl_socket_alloc();
		if (!cmd->sk)
			err_sys("failed to allocate netlink socket");

		/* NB: not setting sk buffer size, using default 32Kb */
		if (genl_connect(cmd->sk))
			err_sys("failed to connect to GeNetlink");
	}

	if (nl80211_id < 0) {
		nl80211_id = genl_ctrl_resolve(cmd->sk, "nl80211");
		if (nl80211_id < 0)
			err_sys("nl80211 not found");
	}

	ifindex = if_nametoindex(conf_ifname());
	if (ifindex == 0 && errno)
		err_sys("failed to look up interface %s", conf_ifname());

	/*
	 * Message Preparation
	 */
	msg = nlmsg_alloc();
	if (!msg)
		err_sys("failed to allocate netlink message");

	cb = nl_cb_alloc(IW_NL_CB_DEBUG ? NL_CB_DEBUG : NL_CB_DEFAULT);
	if (!cb)
		err_sys("failed to allocate netlink callback");

	genlmsg_put(msg, 0, 0, nl80211_id, 0, cmd->flags, cmd->cmd, 0);

	/* netdev identifier: interface index */
	NLA_PUT(msg, NL80211_ATTR_IFINDEX, sizeof(ifindex), &ifindex);

	/* Additional attributes */
	if (cmd->msg_args) {
		for (idx = 0; idx < cmd->msg_args_len; idx++)
			NLA_PUT(msg, cmd->msg_args[idx].type,
				     cmd->msg_args[idx].len,
				     cmd->msg_args[idx].data);
	}

	ret = nl_send_auto_complete(cmd->sk, msg);
	if (ret < 0)
		err_sys("failed to send netlink message");

	/*-------------------------------------------------------------------------
	 * Receive loop
	 *-------------------------------------------------------------------------*/
	nl_cb_err(cb, NL_CB_CUSTOM, error_handler, &ret);
	nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, finish_handler, &ret);
	nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, ack_handler, &ret);
	if (cmd->handler)
		nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, cmd->handler, cmd->handler_arg);

	while (ret > 0)
		nl_recvmsgs(cmd->sk, cb);

	nl_cb_put(cb);
	nlmsg_free(msg);
	goto out;

nla_put_failure:
	err_quit("failed to add attribute to netlink message");
out:
	return ret;
}

/*
 * STATION COMMANDS
 */
/* stolen from iw:station.c */
void parse_bitrate(struct nlattr *bitrate_attr, char *buf, int buflen)
{
	int rate = 0;
	char *pos = buf;
	struct nlattr *rinfo[NL80211_RATE_INFO_MAX + 1];
	static struct nla_policy rate_policy[NL80211_RATE_INFO_MAX + 1] = {
		[NL80211_RATE_INFO_BITRATE] = { .type = NLA_U16 },
		[NL80211_RATE_INFO_BITRATE32] = { .type = NLA_U32 },
		[NL80211_RATE_INFO_MCS] = { .type = NLA_U8 },
		[NL80211_RATE_INFO_40_MHZ_WIDTH] = { .type = NLA_FLAG },
		[NL80211_RATE_INFO_SHORT_GI] = { .type = NLA_FLAG },
	};

	if (nla_parse_nested(rinfo, NL80211_RATE_INFO_MAX,
			     bitrate_attr, rate_policy)) {
		snprintf(buf, buflen, "failed to parse nested rate attributes!");
		return;
	}

	if (rinfo[NL80211_RATE_INFO_BITRATE32])
		rate = nla_get_u32(rinfo[NL80211_RATE_INFO_BITRATE32]);
	else if (rinfo[NL80211_RATE_INFO_BITRATE])
		rate = nla_get_u16(rinfo[NL80211_RATE_INFO_BITRATE]);
	if (rate > 0)
		pos += snprintf(pos, buflen - (pos - buf),
				"%d.%d Mbit/s", rate / 10, rate % 10);

	if (rinfo[NL80211_RATE_INFO_MCS])
		pos += snprintf(pos, buflen - (pos - buf),
				" MCS %d", nla_get_u8(rinfo[NL80211_RATE_INFO_MCS]));
	if (rinfo[NL80211_RATE_INFO_VHT_MCS])
		pos += snprintf(pos, buflen - (pos - buf),
				" VHT-MCS %d", nla_get_u8(rinfo[NL80211_RATE_INFO_VHT_MCS]));
	if (rinfo[NL80211_RATE_INFO_40_MHZ_WIDTH])
		pos += snprintf(pos, buflen - (pos - buf), " 40MHz");
	if (rinfo[NL80211_RATE_INFO_80_MHZ_WIDTH])
		pos += snprintf(pos, buflen - (pos - buf), " 80MHz");
	if (rinfo[NL80211_RATE_INFO_80P80_MHZ_WIDTH])
		pos += snprintf(pos, buflen - (pos - buf), " 80P80MHz");
	if (rinfo[NL80211_RATE_INFO_160_MHZ_WIDTH])
		pos += snprintf(pos, buflen - (pos - buf), " 160MHz");
	if (rinfo[NL80211_RATE_INFO_SHORT_GI])
		pos += snprintf(pos, buflen - (pos - buf), " short GI");
	if (rinfo[NL80211_RATE_INFO_VHT_NSS])
		pos += snprintf(pos, buflen - (pos - buf),
				" VHT-NSS %d", nla_get_u8(rinfo[NL80211_RATE_INFO_VHT_NSS]));
}

/*
 * INTERFACE COMMANDS
 */
void print_ssid_escaped(char *buf, const size_t buflen,
			const uint8_t *data, const size_t datalen)
{
	int i, l;

	memset(buf, '\0', buflen);
	/* Treat zeroed-out SSIDs separately */
	for (i = 0; i < datalen && data[i] == '\0'; i++)
		;
	if (i == datalen)
		return;

	for (i = l= 0; i < datalen; i++) {
		if (l + 4 >= buflen)
			return;
		else if (isprint(data[i]) && data[i] != ' ' && data[i] != '\\')
			l += sprintf(buf + l, "%c", data[i]);
		else if (data[i] == ' ' && i != 0 && i != datalen -1)
			l += sprintf(buf + l, " ");
		else
			l += sprintf(buf + l, "\\x%.2x", data[i]);
	}
}

/* stolen from iw:interface.c */
static int iface_handler(struct nl_msg *msg, void *arg)
{
	struct iw_nl80211_ifstat *ifs = (struct iw_nl80211_ifstat *)arg;
	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
	struct nlattr *tb_msg[NL80211_ATTR_MAX + 1];

	assert(ifs != NULL);

	nla_parse(tb_msg, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
		  genlmsg_attrlen(gnlh, 0), NULL);

	if (tb_msg[NL80211_ATTR_WIPHY])
		ifs->phy = nla_get_u32(tb_msg[NL80211_ATTR_WIPHY]);

	if (tb_msg[NL80211_ATTR_IFINDEX])
		ifs->ifindex = nla_get_u32(tb_msg[NL80211_ATTR_IFINDEX]);

	if (tb_msg[NL80211_ATTR_WDEV])
		ifs->wdev = nla_get_u64(tb_msg[NL80211_ATTR_WDEV]);
	if (tb_msg[NL80211_ATTR_SSID])
		print_ssid_escaped(ifs->ssid, sizeof(ifs->ssid),
				   nla_data(tb_msg[NL80211_ATTR_SSID]),
				   nla_len(tb_msg[NL80211_ATTR_SSID]));

	if (tb_msg[NL80211_ATTR_IFTYPE])
		ifs->iftype = nla_get_u32(tb_msg[NL80211_ATTR_IFTYPE]);

	ifs->chan_width = -1;
	ifs->chan_type  = -1;
	if (tb_msg[NL80211_ATTR_WIPHY_FREQ]) {
		ifs->freq = nla_get_u32(tb_msg[NL80211_ATTR_WIPHY_FREQ]);

		if (tb_msg[NL80211_ATTR_CHANNEL_WIDTH]) {
			ifs->chan_width = nla_get_u32(tb_msg[NL80211_ATTR_CHANNEL_WIDTH]);

			if (tb_msg[NL80211_ATTR_CENTER_FREQ1])
				ifs->freq_ctr1 = nla_get_u32(tb_msg[NL80211_ATTR_CENTER_FREQ1]);
			if (tb_msg[NL80211_ATTR_CENTER_FREQ2])
				ifs->freq_ctr2 = nla_get_u32(tb_msg[NL80211_ATTR_CENTER_FREQ2]);

		}
		if (tb_msg[NL80211_ATTR_WIPHY_CHANNEL_TYPE])
			ifs->chan_type = nla_get_u32(tb_msg[NL80211_ATTR_WIPHY_CHANNEL_TYPE]);
	}

	return NL_SKIP;
}

/**
 * survey_handler - channel survey data
 * This handler will be called multiple times, for each channel.
 * stolen from iw:survey.c
 */
static int survey_handler(struct nl_msg *msg, void *arg)
{
	struct iw_nl80211_survey *sd = (struct iw_nl80211_survey *)arg;
	struct nlattr *tb[NL80211_ATTR_MAX + 1];
	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
	struct nlattr *sinfo[NL80211_SURVEY_INFO_MAX + 1];

	static struct nla_policy survey_policy[NL80211_SURVEY_INFO_MAX + 1] = {
		[NL80211_SURVEY_INFO_FREQUENCY]     = { .type = NLA_U32 },
		[NL80211_SURVEY_INFO_NOISE]         = { .type = NLA_U8 },
		[NL80211_SURVEY_INFO_IN_USE]        = { .type = NLA_FLAG },
		[NL80211_SURVEY_INFO_TIME]          = { .type = NLA_U64 },
		[NL80211_SURVEY_INFO_TIME_BUSY]     = { .type = NLA_U64 },
		[NL80211_SURVEY_INFO_TIME_EXT_BUSY] = { .type = NLA_U64 },
		[NL80211_SURVEY_INFO_TIME_RX]       = { .type = NLA_U64 },
		[NL80211_SURVEY_INFO_TIME_TX]       = { .type = NLA_U64 },
		[NL80211_SURVEY_INFO_TIME_SCAN]     = { .type = NLA_U64 },
	};

	nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
		  genlmsg_attrlen(gnlh, 0), NULL);

	if (!tb[NL80211_ATTR_SURVEY_INFO])
		return NL_SKIP;

	if (nla_parse_nested(sinfo, NL80211_SURVEY_INFO_MAX,
			     tb[NL80211_ATTR_SURVEY_INFO], survey_policy))
		return NL_SKIP;

	/* The frequency is needed to match up with the associated station */
	if (!sinfo[NL80211_SURVEY_INFO_FREQUENCY])
		return NL_SKIP;

	/* We are only interested in the data of the operating channel */
	if (!sinfo[NL80211_SURVEY_INFO_IN_USE])
		return NL_SKIP;

	sd->freq  = nla_get_u32(sinfo[NL80211_SURVEY_INFO_FREQUENCY]);

	if (sinfo[NL80211_SURVEY_INFO_NOISE])
		sd->noise = (int8_t)nla_get_u8(sinfo[NL80211_SURVEY_INFO_NOISE]);

	if (sinfo[NL80211_SURVEY_INFO_TIME])
		sd->time.active = nla_get_u64(sinfo[NL80211_SURVEY_INFO_TIME]);

	if (sinfo[NL80211_SURVEY_INFO_TIME_BUSY])
		sd->time.busy = nla_get_u64(sinfo[NL80211_SURVEY_INFO_TIME_BUSY]);

	if (sinfo[NL80211_SURVEY_INFO_TIME_EXT_BUSY])
		sd->time.ext_busy = nla_get_u64(sinfo[NL80211_SURVEY_INFO_TIME_EXT_BUSY]);

	if (sinfo[NL80211_SURVEY_INFO_TIME_RX])
		sd->time.rx = nla_get_u64(sinfo[NL80211_SURVEY_INFO_TIME_RX]);

	if (sinfo[NL80211_SURVEY_INFO_TIME_TX])
		sd->time.tx = nla_get_u64(sinfo[NL80211_SURVEY_INFO_TIME_TX]);

	if (sinfo[NL80211_SURVEY_INFO_TIME_SCAN])
		sd->time.scan = nla_get_u64(sinfo[NL80211_SURVEY_INFO_TIME_SCAN]);

	return NL_SKIP;
}

/* Regulatory domain, stolen from iw:reg.c */
static int reg_handler(struct nl_msg *msg, void *arg)
{
	struct iw_nl80211_reg *ir = (struct iw_nl80211_reg *)arg;
	struct nlattr *tb_msg[NL80211_ATTR_MAX + 1];
	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
	char *alpha2;

	ir->region = -1;

	nla_parse(tb_msg, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
		genlmsg_attrlen(gnlh, 0), NULL);

	if (!tb_msg[NL80211_ATTR_REG_ALPHA2])
		return NL_SKIP;

	if (!tb_msg[NL80211_ATTR_REG_RULES])
		return NL_SKIP;

	if (tb_msg[NL80211_ATTR_DFS_REGION])
		ir->region = nla_get_u8(tb_msg[NL80211_ATTR_DFS_REGION]);
	else
		ir->region = NL80211_DFS_UNSET;

	alpha2 = nla_data(tb_msg[NL80211_ATTR_REG_ALPHA2]);
	ir->country[0] = alpha2[0];
	ir->country[1] = alpha2[1];

	return NL_SKIP;
}

static int link_handler(struct nl_msg *msg, void *arg)
{
	struct iw_nl80211_linkstat *ls = arg;
	struct nlattr *tb[NL80211_ATTR_MAX + 1];
	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
	struct nlattr *bss[NL80211_BSS_MAX + 1];
	static struct nla_policy bss_policy[NL80211_BSS_MAX + 1] = {
		[NL80211_BSS_TSF] = { .type = NLA_U64 },
		[NL80211_BSS_FREQUENCY] = { .type = NLA_U32 },
		[NL80211_BSS_BSSID] = { },
		[NL80211_BSS_BEACON_INTERVAL] = { .type = NLA_U16 },
		[NL80211_BSS_CAPABILITY] = { .type = NLA_U16 },
		[NL80211_BSS_INFORMATION_ELEMENTS] = { },
		[NL80211_BSS_SIGNAL_MBM] = { .type = NLA_U32 },
		[NL80211_BSS_SIGNAL_UNSPEC] = { .type = NLA_U8 },
		[NL80211_BSS_STATUS] = { .type = NLA_U32 },
	};

	nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
		  genlmsg_attrlen(gnlh, 0), NULL);

	if (!tb[NL80211_ATTR_BSS])
		return NL_SKIP;

	if (nla_parse_nested(bss, NL80211_BSS_MAX, tb[NL80211_ATTR_BSS], bss_policy))
		return NL_SKIP;

	if (!bss[NL80211_BSS_BSSID])
		return NL_SKIP;

	if (!bss[NL80211_BSS_STATUS])
		return NL_SKIP;

	if (bss[NL80211_BSS_SIGNAL_UNSPEC])
		ls->bss_signal_qual = nla_get_u8(bss[NL80211_BSS_SIGNAL_UNSPEC]);

	if (bss[NL80211_BSS_SIGNAL_MBM]) {
		int s = nla_get_u32(bss[NL80211_BSS_SIGNAL_MBM]);
		ls->bss_signal = s / 100;
	}

	ls->status = nla_get_u32(bss[NL80211_BSS_STATUS]);
	switch (ls->status) {
	case NL80211_BSS_STATUS_ASSOCIATED:	/* apparently no longer used */
	case NL80211_BSS_STATUS_AUTHENTICATED:
	case NL80211_BSS_STATUS_IBSS_JOINED:
		memcpy(&ls->bssid, nla_data(bss[NL80211_BSS_BSSID]), ETH_ALEN);
	}

	return NL_SKIP;
}

static int link_sta_handler(struct nl_msg *msg, void *arg)
{
	struct iw_nl80211_linkstat *ls = arg;
	struct nlattr *tb[NL80211_ATTR_MAX + 1];
	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
	struct nlattr *sinfo[NL80211_STA_INFO_MAX + 1];
	struct nlattr *binfo[NL80211_STA_BSS_PARAM_MAX + 1];
	struct nl80211_sta_flag_update *sta_flags;
	static struct nla_policy stats_policy[NL80211_STA_INFO_MAX + 1] = {
		[NL80211_STA_INFO_CONNECTED_TIME] = { .type = NLA_U32 },
		[NL80211_STA_INFO_INACTIVE_TIME] = { .type = NLA_U32 },
		[NL80211_STA_INFO_RX_BYTES] = { .type = NLA_U32 },
		[NL80211_STA_INFO_TX_BYTES] = { .type = NLA_U32 },
		[NL80211_STA_INFO_RX_PACKETS] = { .type = NLA_U32 },
		[NL80211_STA_INFO_TX_PACKETS] = { .type = NLA_U32 },
		[NL80211_STA_INFO_SIGNAL] = { .type = NLA_U8 },
		[NL80211_STA_INFO_SIGNAL_AVG] = { .type = NLA_U8 },
		[NL80211_STA_INFO_T_OFFSET] = { .type = NLA_U64 },
		[NL80211_STA_INFO_TX_BITRATE] = { .type = NLA_NESTED },
		[NL80211_STA_INFO_RX_BITRATE] = { .type = NLA_NESTED },
		[NL80211_STA_INFO_RX_DROP_MISC] = { .type = NLA_U64 },
		[NL80211_STA_INFO_BEACON_RX] = { .type = NLA_U64 },
		[NL80211_STA_INFO_BEACON_LOSS] = { .type = NLA_U32 },
		[NL80211_STA_INFO_BEACON_SIGNAL_AVG] = { .type = NLA_U8 },
		[NL80211_STA_INFO_LLID] = { .type = NLA_U16 },
		[NL80211_STA_INFO_PLID] = { .type = NLA_U16 },
		[NL80211_STA_INFO_PLINK_STATE] = { .type = NLA_U8 },
		[NL80211_STA_INFO_TX_RETRIES] = { .type = NLA_U32 },
		[NL80211_STA_INFO_TX_FAILED] = { .type = NLA_U32 },
		[NL80211_STA_INFO_STA_FLAGS] =
			{ .minlen = sizeof(struct nl80211_sta_flag_update) },
		[NL80211_STA_INFO_LOCAL_PM] = { .type = NLA_U32},
		[NL80211_STA_INFO_PEER_PM] = { .type = NLA_U32},
		[NL80211_STA_INFO_NONPEER_PM] = { .type = NLA_U32},
		[NL80211_STA_INFO_CHAIN_SIGNAL] = { .type = NLA_NESTED },
		[NL80211_STA_INFO_CHAIN_SIGNAL_AVG] = { .type = NLA_NESTED },
	};
	static struct nla_policy bss_policy[NL80211_STA_BSS_PARAM_MAX + 1] = {
		[NL80211_STA_BSS_PARAM_CTS_PROT] = { .type = NLA_FLAG },
		[NL80211_STA_BSS_PARAM_SHORT_PREAMBLE] = { .type = NLA_FLAG },
		[NL80211_STA_BSS_PARAM_SHORT_SLOT_TIME] = { .type = NLA_FLAG },
		[NL80211_STA_BSS_PARAM_DTIM_PERIOD] = { .type = NLA_U8 },
		[NL80211_STA_BSS_PARAM_BEACON_INTERVAL] = { .type = NLA_U16 },
	};

	nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
		  genlmsg_attrlen(gnlh, 0), NULL);

	if (!tb[NL80211_ATTR_STA_INFO])
		return NL_SKIP;

	if (nla_parse_nested(sinfo, NL80211_STA_INFO_MAX,
			     tb[NL80211_ATTR_STA_INFO],
			     stats_policy))
		return NL_SKIP;

	if (sinfo[NL80211_STA_INFO_TX_RETRIES])
		ls->tx_retries = nla_get_u32(sinfo[NL80211_STA_INFO_TX_RETRIES]);
	if (sinfo[NL80211_STA_INFO_TX_FAILED])
		ls->tx_failed = nla_get_u32(sinfo[NL80211_STA_INFO_TX_FAILED]);


	if (sinfo[NL80211_STA_INFO_EXPECTED_THROUGHPUT]) {
		ls->expected_thru = nla_get_u32(sinfo[NL80211_STA_INFO_EXPECTED_THROUGHPUT]);
		/* convert in Mbps but scale by 1000 to save kbps units */
		ls->expected_thru = ls->expected_thru * 1000 / 1024;
	}
	if (sinfo[NL80211_STA_INFO_INACTIVE_TIME])
		ls->inactive_time = nla_get_u32(sinfo[NL80211_STA_INFO_INACTIVE_TIME]);
	if (sinfo[NL80211_STA_INFO_CONNECTED_TIME])
		ls->connected_time = nla_get_u32(sinfo[NL80211_STA_INFO_CONNECTED_TIME]);

	if (sinfo[NL80211_STA_INFO_RX_BYTES])
		ls->rx_bytes = nla_get_u32(sinfo[NL80211_STA_INFO_RX_BYTES]);
	if (sinfo[NL80211_STA_INFO_RX_PACKETS])
		ls->rx_packets = nla_get_u32(sinfo[NL80211_STA_INFO_RX_PACKETS]);
	if (sinfo[NL80211_STA_INFO_RX_DROP_MISC])
		ls->rx_drop_misc = nla_get_u64(sinfo[NL80211_STA_INFO_RX_DROP_MISC]);

	if (sinfo[NL80211_STA_INFO_TX_BYTES])
		ls->tx_bytes = nla_get_u32(sinfo[NL80211_STA_INFO_TX_BYTES]);
	if (sinfo[NL80211_STA_INFO_TX_PACKETS])
		ls->tx_packets = nla_get_u32(sinfo[NL80211_STA_INFO_TX_PACKETS]);

	if (sinfo[NL80211_STA_INFO_SIGNAL])
		ls->signal = (int8_t)nla_get_u8(sinfo[NL80211_STA_INFO_SIGNAL]);
	if (sinfo[NL80211_STA_INFO_SIGNAL_AVG])
		ls->signal_avg = (int8_t)nla_get_u8(sinfo[NL80211_STA_INFO_SIGNAL_AVG]);


	if (sinfo[NL80211_STA_INFO_BEACON_SIGNAL_AVG])
		ls->beacon_avg_sig = nla_get_u8(sinfo[NL80211_STA_INFO_BEACON_SIGNAL_AVG]);
	if (sinfo[NL80211_STA_INFO_BEACON_RX])
		ls->beacons = nla_get_u64(sinfo[NL80211_STA_INFO_BEACON_RX]);
	if (sinfo[NL80211_STA_INFO_BEACON_LOSS])
		ls->beacon_loss = nla_get_u32(sinfo[NL80211_STA_INFO_BEACON_LOSS]);

	if (sinfo[NL80211_STA_INFO_TX_BITRATE])
		parse_bitrate(sinfo[NL80211_STA_INFO_TX_BITRATE], ls->tx_bitrate, sizeof(ls->tx_bitrate));

	if (sinfo[NL80211_STA_INFO_RX_BITRATE])
		parse_bitrate(sinfo[NL80211_STA_INFO_RX_BITRATE], ls->rx_bitrate, sizeof(ls->rx_bitrate));

	if (sinfo[NL80211_STA_INFO_STA_FLAGS]) {
		sta_flags = (struct nl80211_sta_flag_update *)
			    nla_data(sinfo[NL80211_STA_INFO_STA_FLAGS]);

		if (sta_flags->mask & BIT(NL80211_STA_FLAG_SHORT_PREAMBLE) &&
		    sta_flags->set & BIT(NL80211_STA_FLAG_SHORT_PREAMBLE))
			ls->long_preamble = true;

		if (sta_flags->mask & BIT(NL80211_STA_FLAG_WME) &&
		    sta_flags->set & BIT(NL80211_STA_FLAG_WME))
			ls->wme = true;

		if (sta_flags->mask & BIT(NL80211_STA_FLAG_MFP) &&
		    sta_flags->set & BIT(NL80211_STA_FLAG_MFP))
			ls->mfp = true;

		if (sta_flags->mask & BIT(NL80211_STA_FLAG_TDLS_PEER) &&
		    sta_flags->set & BIT(NL80211_STA_FLAG_TDLS_PEER))
			ls->tdls = true;
	}

	/* BSS Flags */
	if (sinfo[NL80211_STA_INFO_BSS_PARAM]) {
		if (nla_parse_nested(binfo, NL80211_STA_BSS_PARAM_MAX,
				     sinfo[NL80211_STA_INFO_BSS_PARAM],
				     bss_policy) == 0) {
			if (binfo[NL80211_STA_BSS_PARAM_CTS_PROT]) {
				ls->cts_protection = true;
			}
			if (binfo[NL80211_STA_BSS_PARAM_SHORT_PREAMBLE])
				ls->long_preamble = false;
			if (binfo[NL80211_STA_BSS_PARAM_SHORT_SLOT_TIME])
				ls->short_slot_time = true;

			ls->beacon_int  = nla_get_u16(binfo[NL80211_STA_BSS_PARAM_BEACON_INTERVAL]);
			ls->dtim_period = nla_get_u8(binfo[NL80211_STA_BSS_PARAM_DTIM_PERIOD]);
		}
	}

	return NL_SKIP;
}

/*
 * COMMAND HANDLERS
 */
void iw_nl80211_get_linkstat(struct iw_nl80211_linkstat *ls)
{
	static struct cmd cmd_linkstat = {
		.cmd	 = NL80211_CMD_GET_SCAN,
		.flags	 = NLM_F_DUMP,
		.handler = link_handler
	};
	static struct cmd cmd_getstation = {
		.cmd	 = NL80211_CMD_GET_STATION,
		.flags	 = 0,
		.handler = link_sta_handler
	};

	struct msg_attribute station_addr = {
		.type = NL80211_ATTR_MAC,
		.len  = sizeof(ls->bssid),
		.data = &ls->bssid
	};

	cmd_linkstat.handler_arg = ls;
	memset(ls, 0, sizeof(*ls));
	handle_cmd(&cmd_linkstat);

	/* If not associated to another station, the bssid is zeroed out */
	if (ether_addr_is_zero(&ls->bssid))
		return;
	/*
	 * Details of the associated station
	 */
	cmd_getstation.handler_arg  = ls;
	cmd_getstation.msg_args     = &station_addr;
	cmd_getstation.msg_args_len = 1;

	handle_cmd(&cmd_getstation);

	/* Channel survey data */
	iw_nl80211_get_survey(&ls->survey);
}

void iw_nl80211_getreg(struct iw_nl80211_reg *ir)
{
	static struct cmd cmd_reg = {
		.cmd	 = NL80211_CMD_GET_REG,
		.flags	 = 0,
		.handler = reg_handler
	};

	cmd_reg.handler_arg = ir;
	memset(ir, 0, sizeof(*ir));
	handle_cmd(&cmd_reg);
}

void iw_nl80211_getifstat(struct iw_nl80211_ifstat *ifs)
{
	static struct cmd cmd_ifstat = {
		.cmd	 = NL80211_CMD_GET_INTERFACE,
		.flags	 = 0,
		.handler = iface_handler
	};

	cmd_ifstat.handler_arg = ifs;
	memset(ifs, 0, sizeof(*ifs));
	handle_cmd(&cmd_ifstat);
}

void iw_nl80211_get_survey(struct iw_nl80211_survey *sd)
{
	static struct cmd cmd_survey = {
		.cmd	 = NL80211_CMD_GET_SURVEY,
		.flags	 = NLM_F_DUMP,
		.handler = survey_handler
	};

	cmd_survey.handler_arg = sd;
	memset(sd, 0, sizeof(*sd));
	handle_cmd(&cmd_survey);
}

/*
 * Multicast Handling
 */
/**
 * struct handler_args - arguments to resolve multicast group
 * @group: group name to resolve
 * @id:    ID it resolves into
 */
struct handler_args {
	const char	*group;
	int		id;
};

/* stolen from iw:genl.c */
static int family_handler(struct nl_msg *msg, void *arg)
{
	struct handler_args *grp = arg;
	struct nlattr *tb[CTRL_ATTR_MAX + 1];
	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
	struct nlattr *mcgrp;
	int rem_mcgrp;

	nla_parse(tb, CTRL_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
		  genlmsg_attrlen(gnlh, 0), NULL);

	if (!tb[CTRL_ATTR_MCAST_GROUPS])
		return NL_SKIP;

	nla_for_each_nested(mcgrp, tb[CTRL_ATTR_MCAST_GROUPS], rem_mcgrp) {
		struct nlattr *tb_mcgrp[CTRL_ATTR_MCAST_GRP_MAX + 1];

		nla_parse(tb_mcgrp, CTRL_ATTR_MCAST_GRP_MAX,
			  nla_data(mcgrp), nla_len(mcgrp), NULL);

		if (!tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME] ||
		    !tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID])
			continue;
		if (strncmp(nla_data(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME]),
			    grp->group, nla_len(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME])))
			continue;
		grp->id = nla_get_u32(tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]);
		break;
	}

	return NL_SKIP;
}

/* stolen from iw:genl.c */
int nl_get_multicast_id(struct nl_sock *sock, const char *family, const char *group)
{
	struct nl_msg *msg;
	struct nl_cb *cb;
	int ret, ctrlid;
	struct handler_args grp = {
		.group = group,
		.id = -ENOENT,
	};

	msg = nlmsg_alloc();
	if (!msg)
		return -ENOMEM;

	cb = nl_cb_alloc(NL_CB_DEFAULT);
	if (!cb) {
		ret = -ENOMEM;
		goto out_fail_cb;
	}

	ctrlid = genl_ctrl_resolve(sock, "nlctrl");

	genlmsg_put(msg, 0, 0, ctrlid, 0,
		    0, CTRL_CMD_GETFAMILY, 0);

	ret = -ENOBUFS;
	NLA_PUT_STRING(msg, CTRL_ATTR_FAMILY_NAME, family);

	ret = nl_send_auto_complete(sock, msg);
	if (ret < 0)
		goto out;

	ret = 1;

	nl_cb_err(cb, NL_CB_CUSTOM, error_handler, &ret);
	nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, ack_handler, &ret);
	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, family_handler, &grp);

	while (ret > 0)
		nl_recvmsgs(sock, cb);

	if (ret == 0)
		ret = grp.id;
nla_put_failure:
out:
	nl_cb_put(cb);
out_fail_cb:
	nlmsg_free(msg);
	return ret;
}

/**
 * Allocate a GeNetlink socket ready to listen for nl80211 multicast group @grp
 * @grp: identifier of an nl80211 multicast group (e.g. "scan")
 */
struct nl_sock *alloc_nl_mcast_sk(const char *grp)
{
	int mcid, ret;
	struct nl_sock *sk = nl_socket_alloc();

	if (!sk)
		err_sys("failed to allocate netlink multicast socket");

	if (genl_connect(sk))
		err_sys("failed to connect multicast socket to GeNetlink");

	mcid = nl_get_multicast_id(sk, "nl80211", grp);
	if (mcid < 0)
		err_quit("failed to resolve nl80211 '%s' multicast group", grp);

	ret = nl_socket_add_membership(sk, mcid);
	if (ret)
		err_sys("failed to join nl80211 multicast group %s", grp);

	return sk;
}