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1 /**
2   * Functions implementing wlan scan IOCTL and firmware command APIs
3   *
4   * IOCTL handlers as well as command preperation and response routines
5   *  for sending scan commands to the firmware.
6   */
7 #include <linux/types.h>
8 #include <linux/etherdevice.h>
9 #include <linux/if_arp.h>
10 #include <asm/unaligned.h>
11 #include <net/lib80211.h>
12 
13 #include "host.h"
14 #include "decl.h"
15 #include "dev.h"
16 #include "scan.h"
17 #include "cmd.h"
18 
19 //! Approximate amount of data needed to pass a scan result back to iwlist
20 #define MAX_SCAN_CELL_SIZE  (IW_EV_ADDR_LEN             \
21                              + IW_ESSID_MAX_SIZE        \
22                              + IW_EV_UINT_LEN           \
23                              + IW_EV_FREQ_LEN           \
24                              + IW_EV_QUAL_LEN           \
25                              + IW_ESSID_MAX_SIZE        \
26                              + IW_EV_PARAM_LEN          \
27                              + 40)	/* 40 for WPAIE */
28 
29 //! Memory needed to store a max sized channel List TLV for a firmware scan
30 #define CHAN_TLV_MAX_SIZE  (sizeof(struct mrvlietypesheader)    \
31                             + (MRVDRV_MAX_CHANNELS_PER_SCAN     \
32                                * sizeof(struct chanscanparamset)))
33 
34 //! Memory needed to store a max number/size SSID TLV for a firmware scan
35 #define SSID_TLV_MAX_SIZE  (1 * sizeof(struct mrvlietypes_ssidparamset))
36 
37 //! Maximum memory needed for a cmd_ds_802_11_scan with all TLVs at max
38 #define MAX_SCAN_CFG_ALLOC (sizeof(struct cmd_ds_802_11_scan)	\
39                             + CHAN_TLV_MAX_SIZE + SSID_TLV_MAX_SIZE)
40 
41 //! The maximum number of channels the firmware can scan per command
42 #define MRVDRV_MAX_CHANNELS_PER_SCAN   14
43 
44 /**
45  * @brief Number of channels to scan per firmware scan command issuance.
46  *
47  *  Number restricted to prevent hitting the limit on the amount of scan data
48  *  returned in a single firmware scan command.
49  */
50 #define MRVDRV_CHANNELS_PER_SCAN_CMD   4
51 
52 //! Scan time specified in the channel TLV for each channel for passive scans
53 #define MRVDRV_PASSIVE_SCAN_CHAN_TIME  100
54 
55 //! Scan time specified in the channel TLV for each channel for active scans
56 #define MRVDRV_ACTIVE_SCAN_CHAN_TIME   100
57 
58 #define DEFAULT_MAX_SCAN_AGE (15 * HZ)
59 
60 static int lbs_ret_80211_scan(struct lbs_private *priv, unsigned long dummy,
61 			      struct cmd_header *resp);
62 
63 /*********************************************************************/
64 /*                                                                   */
65 /*  Misc helper functions                                            */
66 /*                                                                   */
67 /*********************************************************************/
68 
69 /**
70  *  @brief Unsets the MSB on basic rates
71  *
72  * Scan through an array and unset the MSB for basic data rates.
73  *
74  *  @param rates     buffer of data rates
75  *  @param len       size of buffer
76  */
lbs_unset_basic_rate_flags(u8 * rates,size_t len)77 static void lbs_unset_basic_rate_flags(u8 *rates, size_t len)
78 {
79 	int i;
80 
81 	for (i = 0; i < len; i++)
82 		rates[i] &= 0x7f;
83 }
84 
85 
clear_bss_descriptor(struct bss_descriptor * bss)86 static inline void clear_bss_descriptor(struct bss_descriptor *bss)
87 {
88 	/* Don't blow away ->list, just BSS data */
89 	memset(bss, 0, offsetof(struct bss_descriptor, list));
90 }
91 
92 /**
93  *  @brief Compare two SSIDs
94  *
95  *  @param ssid1    A pointer to ssid to compare
96  *  @param ssid2    A pointer to ssid to compare
97  *
98  *  @return         0: ssid is same, otherwise is different
99  */
lbs_ssid_cmp(uint8_t * ssid1,uint8_t ssid1_len,uint8_t * ssid2,uint8_t ssid2_len)100 int lbs_ssid_cmp(uint8_t *ssid1, uint8_t ssid1_len, uint8_t *ssid2,
101 		 uint8_t ssid2_len)
102 {
103 	if (ssid1_len != ssid2_len)
104 		return -1;
105 
106 	return memcmp(ssid1, ssid2, ssid1_len);
107 }
108 
is_same_network(struct bss_descriptor * src,struct bss_descriptor * dst)109 static inline int is_same_network(struct bss_descriptor *src,
110 				  struct bss_descriptor *dst)
111 {
112 	/* A network is only a duplicate if the channel, BSSID, and ESSID
113 	 * all match.  We treat all <hidden> with the same BSSID and channel
114 	 * as one network */
115 	return ((src->ssid_len == dst->ssid_len) &&
116 		(src->channel == dst->channel) &&
117 		!compare_ether_addr(src->bssid, dst->bssid) &&
118 		!memcmp(src->ssid, dst->ssid, src->ssid_len));
119 }
120 
121 
122 
123 
124 /*********************************************************************/
125 /*                                                                   */
126 /*  Main scanning support                                            */
127 /*                                                                   */
128 /*********************************************************************/
129 
130 /**
131  *  @brief Create a channel list for the driver to scan based on region info
132  *
133  *  Only used from lbs_scan_setup_scan_config()
134  *
135  *  Use the driver region/band information to construct a comprehensive list
136  *    of channels to scan.  This routine is used for any scan that is not
137  *    provided a specific channel list to scan.
138  *
139  *  @param priv          A pointer to struct lbs_private structure
140  *  @param scanchanlist  Output parameter: resulting channel list to scan
141  *
142  *  @return              void
143  */
lbs_scan_create_channel_list(struct lbs_private * priv,struct chanscanparamset * scanchanlist)144 static int lbs_scan_create_channel_list(struct lbs_private *priv,
145 					struct chanscanparamset *scanchanlist)
146 {
147 	struct region_channel *scanregion;
148 	struct chan_freq_power *cfp;
149 	int rgnidx;
150 	int chanidx;
151 	int nextchan;
152 	uint8_t scantype;
153 
154 	chanidx = 0;
155 
156 	/* Set the default scan type to the user specified type, will later
157 	 *   be changed to passive on a per channel basis if restricted by
158 	 *   regulatory requirements (11d or 11h)
159 	 */
160 	scantype = CMD_SCAN_TYPE_ACTIVE;
161 
162 	for (rgnidx = 0; rgnidx < ARRAY_SIZE(priv->region_channel); rgnidx++) {
163 		if (priv->enable11d && (priv->connect_status != LBS_CONNECTED)
164 		    && (priv->mesh_connect_status != LBS_CONNECTED)) {
165 			/* Scan all the supported chan for the first scan */
166 			if (!priv->universal_channel[rgnidx].valid)
167 				continue;
168 			scanregion = &priv->universal_channel[rgnidx];
169 
170 			/* clear the parsed_region_chan for the first scan */
171 			memset(&priv->parsed_region_chan, 0x00,
172 			       sizeof(priv->parsed_region_chan));
173 		} else {
174 			if (!priv->region_channel[rgnidx].valid)
175 				continue;
176 			scanregion = &priv->region_channel[rgnidx];
177 		}
178 
179 		for (nextchan = 0; nextchan < scanregion->nrcfp; nextchan++, chanidx++) {
180 			struct chanscanparamset *chan = &scanchanlist[chanidx];
181 
182 			cfp = scanregion->CFP + nextchan;
183 
184 			if (priv->enable11d)
185 				scantype = lbs_get_scan_type_11d(cfp->channel,
186 								 &priv->parsed_region_chan);
187 
188 			if (scanregion->band == BAND_B || scanregion->band == BAND_G)
189 				chan->radiotype = CMD_SCAN_RADIO_TYPE_BG;
190 
191 			if (scantype == CMD_SCAN_TYPE_PASSIVE) {
192 				chan->maxscantime = cpu_to_le16(MRVDRV_PASSIVE_SCAN_CHAN_TIME);
193 				chan->chanscanmode.passivescan = 1;
194 			} else {
195 				chan->maxscantime = cpu_to_le16(MRVDRV_ACTIVE_SCAN_CHAN_TIME);
196 				chan->chanscanmode.passivescan = 0;
197 			}
198 
199 			chan->channumber = cfp->channel;
200 		}
201 	}
202 	return chanidx;
203 }
204 
205 /*
206  * Add SSID TLV of the form:
207  *
208  * TLV-ID SSID     00 00
209  * length          06 00
210  * ssid            4d 4e 54 45 53 54
211  */
lbs_scan_add_ssid_tlv(struct lbs_private * priv,u8 * tlv)212 static int lbs_scan_add_ssid_tlv(struct lbs_private *priv, u8 *tlv)
213 {
214 	struct mrvlietypes_ssidparamset *ssid_tlv = (void *)tlv;
215 
216 	ssid_tlv->header.type = cpu_to_le16(TLV_TYPE_SSID);
217 	ssid_tlv->header.len = cpu_to_le16(priv->scan_ssid_len);
218 	memcpy(ssid_tlv->ssid, priv->scan_ssid, priv->scan_ssid_len);
219 	return sizeof(ssid_tlv->header) + priv->scan_ssid_len;
220 }
221 
222 /*
223  * Add CHANLIST TLV of the form
224  *
225  * TLV-ID CHANLIST 01 01
226  * length          5b 00
227  * channel 1       00 01 00 00 00 64 00
228  *   radio type    00
229  *   channel          01
230  *   scan type           00
231  *   min scan time          00 00
232  *   max scan time                64 00
233  * channel 2       00 02 00 00 00 64 00
234  * channel 3       00 03 00 00 00 64 00
235  * channel 4       00 04 00 00 00 64 00
236  * channel 5       00 05 00 00 00 64 00
237  * channel 6       00 06 00 00 00 64 00
238  * channel 7       00 07 00 00 00 64 00
239  * channel 8       00 08 00 00 00 64 00
240  * channel 9       00 09 00 00 00 64 00
241  * channel 10      00 0a 00 00 00 64 00
242  * channel 11      00 0b 00 00 00 64 00
243  * channel 12      00 0c 00 00 00 64 00
244  * channel 13      00 0d 00 00 00 64 00
245  *
246  */
lbs_scan_add_chanlist_tlv(uint8_t * tlv,struct chanscanparamset * chan_list,int chan_count)247 static int lbs_scan_add_chanlist_tlv(uint8_t *tlv,
248 				     struct chanscanparamset *chan_list,
249 				     int chan_count)
250 {
251 	size_t size = sizeof(struct chanscanparamset) *chan_count;
252 	struct mrvlietypes_chanlistparamset *chan_tlv = (void *)tlv;
253 
254 	chan_tlv->header.type = cpu_to_le16(TLV_TYPE_CHANLIST);
255 	memcpy(chan_tlv->chanscanparam, chan_list, size);
256 	chan_tlv->header.len = cpu_to_le16(size);
257 	return sizeof(chan_tlv->header) + size;
258 }
259 
260 /*
261  * Add RATES TLV of the form
262  *
263  * TLV-ID RATES    01 00
264  * length          0e 00
265  * rates           82 84 8b 96 0c 12 18 24 30 48 60 6c
266  *
267  * The rates are in lbs_bg_rates[], but for the 802.11b
268  * rates the high bit isn't set.
269  */
lbs_scan_add_rates_tlv(uint8_t * tlv)270 static int lbs_scan_add_rates_tlv(uint8_t *tlv)
271 {
272 	int i;
273 	struct mrvlietypes_ratesparamset *rate_tlv = (void *)tlv;
274 
275 	rate_tlv->header.type = cpu_to_le16(TLV_TYPE_RATES);
276 	tlv += sizeof(rate_tlv->header);
277 	for (i = 0; i < MAX_RATES; i++) {
278 		*tlv = lbs_bg_rates[i];
279 		if (*tlv == 0)
280 			break;
281 		/* This code makes sure that the 802.11b rates (1 MBit/s, 2
282 		   MBit/s, 5.5 MBit/s and 11 MBit/s get's the high bit set.
283 		   Note that the values are MBit/s * 2, to mark them as
284 		   basic rates so that the firmware likes it better */
285 		if (*tlv == 0x02 || *tlv == 0x04 ||
286 		    *tlv == 0x0b || *tlv == 0x16)
287 			*tlv |= 0x80;
288 		tlv++;
289 	}
290 	rate_tlv->header.len = cpu_to_le16(i);
291 	return sizeof(rate_tlv->header) + i;
292 }
293 
294 /*
295  * Generate the CMD_802_11_SCAN command with the proper tlv
296  * for a bunch of channels.
297  */
lbs_do_scan(struct lbs_private * priv,uint8_t bsstype,struct chanscanparamset * chan_list,int chan_count)298 static int lbs_do_scan(struct lbs_private *priv, uint8_t bsstype,
299 		       struct chanscanparamset *chan_list, int chan_count)
300 {
301 	int ret = -ENOMEM;
302 	struct cmd_ds_802_11_scan *scan_cmd;
303 	uint8_t *tlv;	/* pointer into our current, growing TLV storage area */
304 
305 	lbs_deb_enter_args(LBS_DEB_SCAN, "bsstype %d, chanlist[].chan %d, chan_count %d",
306 		bsstype, chan_list ? chan_list[0].channumber : -1,
307 		chan_count);
308 
309 	/* create the fixed part for scan command */
310 	scan_cmd = kzalloc(MAX_SCAN_CFG_ALLOC, GFP_KERNEL);
311 	if (scan_cmd == NULL)
312 		goto out;
313 
314 	tlv = scan_cmd->tlvbuffer;
315 	/* TODO: do we need to scan for a specific BSSID?
316 	memcpy(scan_cmd->bssid, priv->scan_bssid, ETH_ALEN); */
317 	scan_cmd->bsstype = bsstype;
318 
319 	/* add TLVs */
320 	if (priv->scan_ssid_len)
321 		tlv += lbs_scan_add_ssid_tlv(priv, tlv);
322 	if (chan_list && chan_count)
323 		tlv += lbs_scan_add_chanlist_tlv(tlv, chan_list, chan_count);
324 	tlv += lbs_scan_add_rates_tlv(tlv);
325 
326 	/* This is the final data we are about to send */
327 	scan_cmd->hdr.size = cpu_to_le16(tlv - (uint8_t *)scan_cmd);
328 	lbs_deb_hex(LBS_DEB_SCAN, "SCAN_CMD", (void *)scan_cmd,
329 		    sizeof(*scan_cmd));
330 	lbs_deb_hex(LBS_DEB_SCAN, "SCAN_TLV", scan_cmd->tlvbuffer,
331 		    tlv - scan_cmd->tlvbuffer);
332 
333 	ret = __lbs_cmd(priv, CMD_802_11_SCAN, &scan_cmd->hdr,
334 			le16_to_cpu(scan_cmd->hdr.size),
335 			lbs_ret_80211_scan, 0);
336 
337 out:
338 	kfree(scan_cmd);
339 	lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
340 	return ret;
341 }
342 
343 /**
344  *  @brief Internal function used to start a scan based on an input config
345  *
346  *  Use the input user scan configuration information when provided in
347  *    order to send the appropriate scan commands to firmware to populate or
348  *    update the internal driver scan table
349  *
350  *  @param priv          A pointer to struct lbs_private structure
351  *  @param full_scan     Do a full-scan (blocking)
352  *
353  *  @return              0 or < 0 if error
354  */
lbs_scan_networks(struct lbs_private * priv,int full_scan)355 int lbs_scan_networks(struct lbs_private *priv, int full_scan)
356 {
357 	int ret = -ENOMEM;
358 	struct chanscanparamset *chan_list;
359 	struct chanscanparamset *curr_chans;
360 	int chan_count;
361 	uint8_t bsstype = CMD_BSS_TYPE_ANY;
362 	int numchannels = MRVDRV_CHANNELS_PER_SCAN_CMD;
363 	union iwreq_data wrqu;
364 #ifdef CONFIG_LIBERTAS_DEBUG
365 	struct bss_descriptor *iter;
366 	int i = 0;
367 	DECLARE_SSID_BUF(ssid);
368 #endif
369 
370 	lbs_deb_enter_args(LBS_DEB_SCAN, "full_scan %d", full_scan);
371 
372 	/* Cancel any partial outstanding partial scans if this scan
373 	 * is a full scan.
374 	 */
375 	if (full_scan && delayed_work_pending(&priv->scan_work))
376 		cancel_delayed_work(&priv->scan_work);
377 
378 	/* User-specified bsstype or channel list
379 	TODO: this can be implemented if some user-space application
380 	need the feature. Formerly, it was accessible from debugfs,
381 	but then nowhere used.
382 	if (user_cfg) {
383 		if (user_cfg->bsstype)
384 		bsstype = user_cfg->bsstype;
385 	} */
386 
387 	lbs_deb_scan("numchannels %d, bsstype %d\n", numchannels, bsstype);
388 
389 	/* Create list of channels to scan */
390 	chan_list = kzalloc(sizeof(struct chanscanparamset) *
391 			    LBS_IOCTL_USER_SCAN_CHAN_MAX, GFP_KERNEL);
392 	if (!chan_list) {
393 		lbs_pr_alert("SCAN: chan_list empty\n");
394 		goto out;
395 	}
396 
397 	/* We want to scan all channels */
398 	chan_count = lbs_scan_create_channel_list(priv, chan_list);
399 
400 	netif_stop_queue(priv->dev);
401 	netif_carrier_off(priv->dev);
402 	if (priv->mesh_dev) {
403 		netif_stop_queue(priv->mesh_dev);
404 		netif_carrier_off(priv->mesh_dev);
405 	}
406 
407 	/* Prepare to continue an interrupted scan */
408 	lbs_deb_scan("chan_count %d, scan_channel %d\n",
409 		     chan_count, priv->scan_channel);
410 	curr_chans = chan_list;
411 	/* advance channel list by already-scanned-channels */
412 	if (priv->scan_channel > 0) {
413 		curr_chans += priv->scan_channel;
414 		chan_count -= priv->scan_channel;
415 	}
416 
417 	/* Send scan command(s)
418 	 * numchannels contains the number of channels we should maximally scan
419 	 * chan_count is the total number of channels to scan
420 	 */
421 
422 	while (chan_count) {
423 		int to_scan = min(numchannels, chan_count);
424 		lbs_deb_scan("scanning %d of %d channels\n",
425 			     to_scan, chan_count);
426 		ret = lbs_do_scan(priv, bsstype, curr_chans,
427 				  to_scan);
428 		if (ret) {
429 			lbs_pr_err("SCAN_CMD failed\n");
430 			goto out2;
431 		}
432 		curr_chans += to_scan;
433 		chan_count -= to_scan;
434 
435 		/* somehow schedule the next part of the scan */
436 		if (chan_count && !full_scan &&
437 		    !priv->surpriseremoved) {
438 			/* -1 marks just that we're currently scanning */
439 			if (priv->scan_channel < 0)
440 				priv->scan_channel = to_scan;
441 			else
442 				priv->scan_channel += to_scan;
443 			cancel_delayed_work(&priv->scan_work);
444 			queue_delayed_work(priv->work_thread, &priv->scan_work,
445 					   msecs_to_jiffies(300));
446 			/* skip over GIWSCAN event */
447 			goto out;
448 		}
449 
450 	}
451 	memset(&wrqu, 0, sizeof(union iwreq_data));
452 	wireless_send_event(priv->dev, SIOCGIWSCAN, &wrqu, NULL);
453 
454 #ifdef CONFIG_LIBERTAS_DEBUG
455 	/* Dump the scan table */
456 	mutex_lock(&priv->lock);
457 	lbs_deb_scan("scan table:\n");
458 	list_for_each_entry(iter, &priv->network_list, list)
459 		lbs_deb_scan("%02d: BSSID %pM, RSSI %d, SSID '%s'\n",
460 			     i++, iter->bssid, iter->rssi,
461 			     print_ssid(ssid, iter->ssid, iter->ssid_len));
462 	mutex_unlock(&priv->lock);
463 #endif
464 
465 out2:
466 	priv->scan_channel = 0;
467 
468 out:
469 	if (priv->connect_status == LBS_CONNECTED) {
470 		netif_carrier_on(priv->dev);
471 		if (!priv->tx_pending_len)
472 			netif_wake_queue(priv->dev);
473 	}
474 	if (priv->mesh_dev && (priv->mesh_connect_status == LBS_CONNECTED)) {
475 		netif_carrier_on(priv->mesh_dev);
476 		if (!priv->tx_pending_len)
477 			netif_wake_queue(priv->mesh_dev);
478 	}
479 	kfree(chan_list);
480 
481 	lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
482 	return ret;
483 }
484 
lbs_scan_worker(struct work_struct * work)485 void lbs_scan_worker(struct work_struct *work)
486 {
487 	struct lbs_private *priv =
488 		container_of(work, struct lbs_private, scan_work.work);
489 
490 	lbs_deb_enter(LBS_DEB_SCAN);
491 	lbs_scan_networks(priv, 0);
492 	lbs_deb_leave(LBS_DEB_SCAN);
493 }
494 
495 
496 /*********************************************************************/
497 /*                                                                   */
498 /*  Result interpretation                                            */
499 /*                                                                   */
500 /*********************************************************************/
501 
502 /**
503  *  @brief Interpret a BSS scan response returned from the firmware
504  *
505  *  Parse the various fixed fields and IEs passed back for a a BSS probe
506  *  response or beacon from the scan command.  Record information as needed
507  *  in the scan table struct bss_descriptor for that entry.
508  *
509  *  @param bss  Output parameter: Pointer to the BSS Entry
510  *
511  *  @return             0 or -1
512  */
lbs_process_bss(struct bss_descriptor * bss,uint8_t ** pbeaconinfo,int * bytesleft)513 static int lbs_process_bss(struct bss_descriptor *bss,
514 			   uint8_t **pbeaconinfo, int *bytesleft)
515 {
516 	struct ieeetypes_fhparamset *pFH;
517 	struct ieeetypes_dsparamset *pDS;
518 	struct ieeetypes_cfparamset *pCF;
519 	struct ieeetypes_ibssparamset *pibss;
520 	DECLARE_SSID_BUF(ssid);
521 	struct ieeetypes_countryinfoset *pcountryinfo;
522 	uint8_t *pos, *end, *p;
523 	uint8_t n_ex_rates = 0, got_basic_rates = 0, n_basic_rates = 0;
524 	uint16_t beaconsize = 0;
525 	int ret;
526 
527 	lbs_deb_enter(LBS_DEB_SCAN);
528 
529 	if (*bytesleft >= sizeof(beaconsize)) {
530 		/* Extract & convert beacon size from the command buffer */
531 		beaconsize = get_unaligned_le16(*pbeaconinfo);
532 		*bytesleft -= sizeof(beaconsize);
533 		*pbeaconinfo += sizeof(beaconsize);
534 	}
535 
536 	if (beaconsize == 0 || beaconsize > *bytesleft) {
537 		*pbeaconinfo += *bytesleft;
538 		*bytesleft = 0;
539 		ret = -1;
540 		goto done;
541 	}
542 
543 	/* Initialize the current working beacon pointer for this BSS iteration */
544 	pos = *pbeaconinfo;
545 	end = pos + beaconsize;
546 
547 	/* Advance the return beacon pointer past the current beacon */
548 	*pbeaconinfo += beaconsize;
549 	*bytesleft -= beaconsize;
550 
551 	memcpy(bss->bssid, pos, ETH_ALEN);
552 	lbs_deb_scan("process_bss: BSSID %pM\n", bss->bssid);
553 	pos += ETH_ALEN;
554 
555 	if ((end - pos) < 12) {
556 		lbs_deb_scan("process_bss: Not enough bytes left\n");
557 		ret = -1;
558 		goto done;
559 	}
560 
561 	/*
562 	 * next 4 fields are RSSI, time stamp, beacon interval,
563 	 *   and capability information
564 	 */
565 
566 	/* RSSI is 1 byte long */
567 	bss->rssi = *pos;
568 	lbs_deb_scan("process_bss: RSSI %d\n", *pos);
569 	pos++;
570 
571 	/* time stamp is 8 bytes long */
572 	pos += 8;
573 
574 	/* beacon interval is 2 bytes long */
575 	bss->beaconperiod = get_unaligned_le16(pos);
576 	pos += 2;
577 
578 	/* capability information is 2 bytes long */
579 	bss->capability = get_unaligned_le16(pos);
580 	lbs_deb_scan("process_bss: capabilities 0x%04x\n", bss->capability);
581 	pos += 2;
582 
583 	if (bss->capability & WLAN_CAPABILITY_PRIVACY)
584 		lbs_deb_scan("process_bss: WEP enabled\n");
585 	if (bss->capability & WLAN_CAPABILITY_IBSS)
586 		bss->mode = IW_MODE_ADHOC;
587 	else
588 		bss->mode = IW_MODE_INFRA;
589 
590 	/* rest of the current buffer are IE's */
591 	lbs_deb_scan("process_bss: IE len %zd\n", end - pos);
592 	lbs_deb_hex(LBS_DEB_SCAN, "process_bss: IE info", pos, end - pos);
593 
594 	/* process variable IE */
595 	while (pos <= end - 2) {
596 		if (pos + pos[1] > end) {
597 			lbs_deb_scan("process_bss: error in processing IE, "
598 				     "bytes left < IE length\n");
599 			break;
600 		}
601 
602 		switch (pos[0]) {
603 		case WLAN_EID_SSID:
604 			bss->ssid_len = min_t(int, IEEE80211_MAX_SSID_LEN, pos[1]);
605 			memcpy(bss->ssid, pos + 2, bss->ssid_len);
606 			lbs_deb_scan("got SSID IE: '%s', len %u\n",
607 			             print_ssid(ssid, bss->ssid, bss->ssid_len),
608 			             bss->ssid_len);
609 			break;
610 
611 		case WLAN_EID_SUPP_RATES:
612 			n_basic_rates = min_t(uint8_t, MAX_RATES, pos[1]);
613 			memcpy(bss->rates, pos + 2, n_basic_rates);
614 			got_basic_rates = 1;
615 			lbs_deb_scan("got RATES IE\n");
616 			break;
617 
618 		case WLAN_EID_FH_PARAMS:
619 			pFH = (struct ieeetypes_fhparamset *) pos;
620 			memmove(&bss->phyparamset.fhparamset, pFH,
621 				sizeof(struct ieeetypes_fhparamset));
622 			lbs_deb_scan("got FH IE\n");
623 			break;
624 
625 		case WLAN_EID_DS_PARAMS:
626 			pDS = (struct ieeetypes_dsparamset *) pos;
627 			bss->channel = pDS->currentchan;
628 			memcpy(&bss->phyparamset.dsparamset, pDS,
629 			       sizeof(struct ieeetypes_dsparamset));
630 			lbs_deb_scan("got DS IE, channel %d\n", bss->channel);
631 			break;
632 
633 		case WLAN_EID_CF_PARAMS:
634 			pCF = (struct ieeetypes_cfparamset *) pos;
635 			memcpy(&bss->ssparamset.cfparamset, pCF,
636 			       sizeof(struct ieeetypes_cfparamset));
637 			lbs_deb_scan("got CF IE\n");
638 			break;
639 
640 		case WLAN_EID_IBSS_PARAMS:
641 			pibss = (struct ieeetypes_ibssparamset *) pos;
642 			bss->atimwindow = le16_to_cpu(pibss->atimwindow);
643 			memmove(&bss->ssparamset.ibssparamset, pibss,
644 				sizeof(struct ieeetypes_ibssparamset));
645 			lbs_deb_scan("got IBSS IE\n");
646 			break;
647 
648 		case WLAN_EID_COUNTRY:
649 			pcountryinfo = (struct ieeetypes_countryinfoset *) pos;
650 			lbs_deb_scan("got COUNTRY IE\n");
651 			if (pcountryinfo->len < sizeof(pcountryinfo->countrycode)
652 			    || pcountryinfo->len > 254) {
653 				lbs_deb_scan("process_bss: 11D- Err CountryInfo len %d, min %zd, max 254\n",
654 					     pcountryinfo->len, sizeof(pcountryinfo->countrycode));
655 				ret = -1;
656 				goto done;
657 			}
658 
659 			memcpy(&bss->countryinfo, pcountryinfo, pcountryinfo->len + 2);
660 			lbs_deb_hex(LBS_DEB_SCAN, "process_bss: 11d countryinfo",
661 				    (uint8_t *) pcountryinfo,
662 				    (int) (pcountryinfo->len + 2));
663 			break;
664 
665 		case WLAN_EID_EXT_SUPP_RATES:
666 			/* only process extended supported rate if data rate is
667 			 * already found. Data rate IE should come before
668 			 * extended supported rate IE
669 			 */
670 			lbs_deb_scan("got RATESEX IE\n");
671 			if (!got_basic_rates) {
672 				lbs_deb_scan("... but ignoring it\n");
673 				break;
674 			}
675 
676 			n_ex_rates = pos[1];
677 			if (n_basic_rates + n_ex_rates > MAX_RATES)
678 				n_ex_rates = MAX_RATES - n_basic_rates;
679 
680 			p = bss->rates + n_basic_rates;
681 			memcpy(p, pos + 2, n_ex_rates);
682 			break;
683 
684 		case WLAN_EID_GENERIC:
685 			if (pos[1] >= 4 &&
686 			    pos[2] == 0x00 && pos[3] == 0x50 &&
687 			    pos[4] == 0xf2 && pos[5] == 0x01) {
688 				bss->wpa_ie_len = min(pos[1] + 2, MAX_WPA_IE_LEN);
689 				memcpy(bss->wpa_ie, pos, bss->wpa_ie_len);
690 				lbs_deb_scan("got WPA IE\n");
691 				lbs_deb_hex(LBS_DEB_SCAN, "WPA IE", bss->wpa_ie,
692 					    bss->wpa_ie_len);
693 			} else if (pos[1] >= MARVELL_MESH_IE_LENGTH &&
694 				   pos[2] == 0x00 && pos[3] == 0x50 &&
695 				   pos[4] == 0x43 && pos[4] == 0x04) {
696 				lbs_deb_scan("got mesh IE\n");
697 				bss->mesh = 1;
698 			} else {
699 				lbs_deb_scan("got generic IE: %02x:%02x:%02x:%02x, len %d\n",
700 					pos[2], pos[3],
701 					pos[4], pos[5],
702 					pos[1]);
703 			}
704 			break;
705 
706 		case WLAN_EID_RSN:
707 			lbs_deb_scan("got RSN IE\n");
708 			bss->rsn_ie_len = min(pos[1] + 2, MAX_WPA_IE_LEN);
709 			memcpy(bss->rsn_ie, pos, bss->rsn_ie_len);
710 			lbs_deb_hex(LBS_DEB_SCAN, "process_bss: RSN_IE",
711 				    bss->rsn_ie, bss->rsn_ie_len);
712 			break;
713 
714 		default:
715 			lbs_deb_scan("got IE 0x%04x, len %d\n",
716 				     pos[0], pos[1]);
717 			break;
718 		}
719 
720 		pos += pos[1] + 2;
721 	}
722 
723 	/* Timestamp */
724 	bss->last_scanned = jiffies;
725 	lbs_unset_basic_rate_flags(bss->rates, sizeof(bss->rates));
726 
727 	ret = 0;
728 
729 done:
730 	lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
731 	return ret;
732 }
733 
734 /**
735  *  @brief Send a scan command for all available channels filtered on a spec
736  *
737  *  Used in association code and from debugfs
738  *
739  *  @param priv             A pointer to struct lbs_private structure
740  *  @param ssid             A pointer to the SSID to scan for
741  *  @param ssid_len         Length of the SSID
742  *
743  *  @return                0-success, otherwise fail
744  */
lbs_send_specific_ssid_scan(struct lbs_private * priv,uint8_t * ssid,uint8_t ssid_len)745 int lbs_send_specific_ssid_scan(struct lbs_private *priv, uint8_t *ssid,
746 				uint8_t ssid_len)
747 {
748 	DECLARE_SSID_BUF(ssid_buf);
749 	int ret = 0;
750 
751 	lbs_deb_enter_args(LBS_DEB_SCAN, "SSID '%s'\n",
752 			   print_ssid(ssid_buf, ssid, ssid_len));
753 
754 	if (!ssid_len)
755 		goto out;
756 
757 	memcpy(priv->scan_ssid, ssid, ssid_len);
758 	priv->scan_ssid_len = ssid_len;
759 
760 	lbs_scan_networks(priv, 1);
761 	if (priv->surpriseremoved) {
762 		ret = -1;
763 		goto out;
764 	}
765 
766 out:
767 	lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
768 	return ret;
769 }
770 
771 
772 
773 
774 /*********************************************************************/
775 /*                                                                   */
776 /*  Support for Wireless Extensions                                  */
777 /*                                                                   */
778 /*********************************************************************/
779 
780 
781 #define MAX_CUSTOM_LEN 64
782 
lbs_translate_scan(struct lbs_private * priv,struct iw_request_info * info,char * start,char * stop,struct bss_descriptor * bss)783 static inline char *lbs_translate_scan(struct lbs_private *priv,
784 					    struct iw_request_info *info,
785 					    char *start, char *stop,
786 					    struct bss_descriptor *bss)
787 {
788 	struct chan_freq_power *cfp;
789 	char *current_val;	/* For rates */
790 	struct iw_event iwe;	/* Temporary buffer */
791 	int j;
792 #define PERFECT_RSSI ((uint8_t)50)
793 #define WORST_RSSI   ((uint8_t)0)
794 #define RSSI_DIFF    ((uint8_t)(PERFECT_RSSI - WORST_RSSI))
795 	uint8_t rssi;
796 
797 	lbs_deb_enter(LBS_DEB_SCAN);
798 
799 	cfp = lbs_find_cfp_by_band_and_channel(priv, 0, bss->channel);
800 	if (!cfp) {
801 		lbs_deb_scan("Invalid channel number %d\n", bss->channel);
802 		start = NULL;
803 		goto out;
804 	}
805 
806 	/* First entry *MUST* be the BSSID */
807 	iwe.cmd = SIOCGIWAP;
808 	iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
809 	memcpy(iwe.u.ap_addr.sa_data, &bss->bssid, ETH_ALEN);
810 	start = iwe_stream_add_event(info, start, stop, &iwe, IW_EV_ADDR_LEN);
811 
812 	/* SSID */
813 	iwe.cmd = SIOCGIWESSID;
814 	iwe.u.data.flags = 1;
815 	iwe.u.data.length = min((uint32_t) bss->ssid_len, (uint32_t) IW_ESSID_MAX_SIZE);
816 	start = iwe_stream_add_point(info, start, stop, &iwe, bss->ssid);
817 
818 	/* Mode */
819 	iwe.cmd = SIOCGIWMODE;
820 	iwe.u.mode = bss->mode;
821 	start = iwe_stream_add_event(info, start, stop, &iwe, IW_EV_UINT_LEN);
822 
823 	/* Frequency */
824 	iwe.cmd = SIOCGIWFREQ;
825 	iwe.u.freq.m = (long)cfp->freq * 100000;
826 	iwe.u.freq.e = 1;
827 	start = iwe_stream_add_event(info, start, stop, &iwe, IW_EV_FREQ_LEN);
828 
829 	/* Add quality statistics */
830 	iwe.cmd = IWEVQUAL;
831 	iwe.u.qual.updated = IW_QUAL_ALL_UPDATED;
832 	iwe.u.qual.level = SCAN_RSSI(bss->rssi);
833 
834 	rssi = iwe.u.qual.level - MRVDRV_NF_DEFAULT_SCAN_VALUE;
835 	iwe.u.qual.qual =
836 		(100 * RSSI_DIFF * RSSI_DIFF - (PERFECT_RSSI - rssi) *
837 		 (15 * (RSSI_DIFF) + 62 * (PERFECT_RSSI - rssi))) /
838 		(RSSI_DIFF * RSSI_DIFF);
839 	if (iwe.u.qual.qual > 100)
840 		iwe.u.qual.qual = 100;
841 
842 	if (priv->NF[TYPE_BEACON][TYPE_NOAVG] == 0) {
843 		iwe.u.qual.noise = MRVDRV_NF_DEFAULT_SCAN_VALUE;
844 	} else {
845 		iwe.u.qual.noise = CAL_NF(priv->NF[TYPE_BEACON][TYPE_NOAVG]);
846 	}
847 
848 	/* Locally created ad-hoc BSSs won't have beacons if this is the
849 	 * only station in the adhoc network; so get signal strength
850 	 * from receive statistics.
851 	 */
852 	if ((priv->mode == IW_MODE_ADHOC) && priv->adhoccreate
853 	    && !lbs_ssid_cmp(priv->curbssparams.ssid,
854 			     priv->curbssparams.ssid_len,
855 			     bss->ssid, bss->ssid_len)) {
856 		int snr, nf;
857 		snr = priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
858 		nf = priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
859 		iwe.u.qual.level = CAL_RSSI(snr, nf);
860 	}
861 	start = iwe_stream_add_event(info, start, stop, &iwe, IW_EV_QUAL_LEN);
862 
863 	/* Add encryption capability */
864 	iwe.cmd = SIOCGIWENCODE;
865 	if (bss->capability & WLAN_CAPABILITY_PRIVACY) {
866 		iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
867 	} else {
868 		iwe.u.data.flags = IW_ENCODE_DISABLED;
869 	}
870 	iwe.u.data.length = 0;
871 	start = iwe_stream_add_point(info, start, stop, &iwe, bss->ssid);
872 
873 	current_val = start + iwe_stream_lcp_len(info);
874 
875 	iwe.cmd = SIOCGIWRATE;
876 	iwe.u.bitrate.fixed = 0;
877 	iwe.u.bitrate.disabled = 0;
878 	iwe.u.bitrate.value = 0;
879 
880 	for (j = 0; bss->rates[j] && (j < sizeof(bss->rates)); j++) {
881 		/* Bit rate given in 500 kb/s units */
882 		iwe.u.bitrate.value = bss->rates[j] * 500000;
883 		current_val = iwe_stream_add_value(info, start, current_val,
884 						   stop, &iwe, IW_EV_PARAM_LEN);
885 	}
886 	if ((bss->mode == IW_MODE_ADHOC) && priv->adhoccreate
887 	    && !lbs_ssid_cmp(priv->curbssparams.ssid,
888 			     priv->curbssparams.ssid_len,
889 			     bss->ssid, bss->ssid_len)) {
890 		iwe.u.bitrate.value = 22 * 500000;
891 		current_val = iwe_stream_add_value(info, start, current_val,
892 						   stop, &iwe, IW_EV_PARAM_LEN);
893 	}
894 	/* Check if we added any event */
895 	if ((current_val - start) > iwe_stream_lcp_len(info))
896 		start = current_val;
897 
898 	memset(&iwe, 0, sizeof(iwe));
899 	if (bss->wpa_ie_len) {
900 		char buf[MAX_WPA_IE_LEN];
901 		memcpy(buf, bss->wpa_ie, bss->wpa_ie_len);
902 		iwe.cmd = IWEVGENIE;
903 		iwe.u.data.length = bss->wpa_ie_len;
904 		start = iwe_stream_add_point(info, start, stop, &iwe, buf);
905 	}
906 
907 	memset(&iwe, 0, sizeof(iwe));
908 	if (bss->rsn_ie_len) {
909 		char buf[MAX_WPA_IE_LEN];
910 		memcpy(buf, bss->rsn_ie, bss->rsn_ie_len);
911 		iwe.cmd = IWEVGENIE;
912 		iwe.u.data.length = bss->rsn_ie_len;
913 		start = iwe_stream_add_point(info, start, stop, &iwe, buf);
914 	}
915 
916 	if (bss->mesh) {
917 		char custom[MAX_CUSTOM_LEN];
918 		char *p = custom;
919 
920 		iwe.cmd = IWEVCUSTOM;
921 		p += snprintf(p, MAX_CUSTOM_LEN, "mesh-type: olpc");
922 		iwe.u.data.length = p - custom;
923 		if (iwe.u.data.length)
924 			start = iwe_stream_add_point(info, start, stop,
925 						     &iwe, custom);
926 	}
927 
928 out:
929 	lbs_deb_leave_args(LBS_DEB_SCAN, "start %p", start);
930 	return start;
931 }
932 
933 
934 /**
935  *  @brief Handle Scan Network ioctl
936  *
937  *  @param dev          A pointer to net_device structure
938  *  @param info         A pointer to iw_request_info structure
939  *  @param vwrq         A pointer to iw_param structure
940  *  @param extra        A pointer to extra data buf
941  *
942  *  @return             0 --success, otherwise fail
943  */
lbs_set_scan(struct net_device * dev,struct iw_request_info * info,union iwreq_data * wrqu,char * extra)944 int lbs_set_scan(struct net_device *dev, struct iw_request_info *info,
945 		 union iwreq_data *wrqu, char *extra)
946 {
947 	DECLARE_SSID_BUF(ssid);
948 	struct lbs_private *priv = dev->ml_priv;
949 	int ret = 0;
950 
951 	lbs_deb_enter(LBS_DEB_WEXT);
952 
953 	if (!priv->radio_on) {
954 		ret = -EINVAL;
955 		goto out;
956 	}
957 
958 	if (!netif_running(dev)) {
959 		ret = -ENETDOWN;
960 		goto out;
961 	}
962 
963 	/* mac80211 does this:
964 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
965 	if (sdata->type != IEEE80211_IF_TYPE_xxx) {
966 		ret = -EOPNOTSUPP;
967 		goto out;
968 	}
969 	*/
970 
971 	if (wrqu->data.length == sizeof(struct iw_scan_req) &&
972 	    wrqu->data.flags & IW_SCAN_THIS_ESSID) {
973 		struct iw_scan_req *req = (struct iw_scan_req *)extra;
974 		priv->scan_ssid_len = req->essid_len;
975 		memcpy(priv->scan_ssid, req->essid, priv->scan_ssid_len);
976 		lbs_deb_wext("set_scan, essid '%s'\n",
977 			print_ssid(ssid, priv->scan_ssid, priv->scan_ssid_len));
978 	} else {
979 		priv->scan_ssid_len = 0;
980 	}
981 
982 	if (!delayed_work_pending(&priv->scan_work))
983 		queue_delayed_work(priv->work_thread, &priv->scan_work,
984 				   msecs_to_jiffies(50));
985 	/* set marker that currently a scan is taking place */
986 	priv->scan_channel = -1;
987 
988 	if (priv->surpriseremoved)
989 		ret = -EIO;
990 
991 out:
992 	lbs_deb_leave_args(LBS_DEB_WEXT, "ret %d", ret);
993 	return ret;
994 }
995 
996 
997 /**
998  *  @brief  Handle Retrieve scan table ioctl
999  *
1000  *  @param dev          A pointer to net_device structure
1001  *  @param info         A pointer to iw_request_info structure
1002  *  @param dwrq         A pointer to iw_point structure
1003  *  @param extra        A pointer to extra data buf
1004  *
1005  *  @return             0 --success, otherwise fail
1006  */
lbs_get_scan(struct net_device * dev,struct iw_request_info * info,struct iw_point * dwrq,char * extra)1007 int lbs_get_scan(struct net_device *dev, struct iw_request_info *info,
1008 		 struct iw_point *dwrq, char *extra)
1009 {
1010 #define SCAN_ITEM_SIZE 128
1011 	struct lbs_private *priv = dev->ml_priv;
1012 	int err = 0;
1013 	char *ev = extra;
1014 	char *stop = ev + dwrq->length;
1015 	struct bss_descriptor *iter_bss;
1016 	struct bss_descriptor *safe;
1017 
1018 	lbs_deb_enter(LBS_DEB_WEXT);
1019 
1020 	/* iwlist should wait until the current scan is finished */
1021 	if (priv->scan_channel)
1022 		return -EAGAIN;
1023 
1024 	/* Update RSSI if current BSS is a locally created ad-hoc BSS */
1025 	if ((priv->mode == IW_MODE_ADHOC) && priv->adhoccreate)
1026 		lbs_prepare_and_send_command(priv, CMD_802_11_RSSI, 0,
1027 					     CMD_OPTION_WAITFORRSP, 0, NULL);
1028 
1029 	mutex_lock(&priv->lock);
1030 	list_for_each_entry_safe (iter_bss, safe, &priv->network_list, list) {
1031 		char *next_ev;
1032 		unsigned long stale_time;
1033 
1034 		if (stop - ev < SCAN_ITEM_SIZE) {
1035 			err = -E2BIG;
1036 			break;
1037 		}
1038 
1039 		/* For mesh device, list only mesh networks */
1040 		if (dev == priv->mesh_dev && !iter_bss->mesh)
1041 			continue;
1042 
1043 		/* Prune old an old scan result */
1044 		stale_time = iter_bss->last_scanned + DEFAULT_MAX_SCAN_AGE;
1045 		if (time_after(jiffies, stale_time)) {
1046 			list_move_tail(&iter_bss->list, &priv->network_free_list);
1047 			clear_bss_descriptor(iter_bss);
1048 			continue;
1049 		}
1050 
1051 		/* Translate to WE format this entry */
1052 		next_ev = lbs_translate_scan(priv, info, ev, stop, iter_bss);
1053 		if (next_ev == NULL)
1054 			continue;
1055 		ev = next_ev;
1056 	}
1057 	mutex_unlock(&priv->lock);
1058 
1059 	dwrq->length = (ev - extra);
1060 	dwrq->flags = 0;
1061 
1062 	lbs_deb_leave_args(LBS_DEB_WEXT, "ret %d", err);
1063 	return err;
1064 }
1065 
1066 
1067 
1068 
1069 /*********************************************************************/
1070 /*                                                                   */
1071 /*  Command execution                                                */
1072 /*                                                                   */
1073 /*********************************************************************/
1074 
1075 
1076 /**
1077  *  @brief This function handles the command response of scan
1078  *
1079  *  Called from handle_cmd_response() in cmdrespc.
1080  *
1081  *   The response buffer for the scan command has the following
1082  *      memory layout:
1083  *
1084  *     .-----------------------------------------------------------.
1085  *     |  header (4 * sizeof(u16)):  Standard command response hdr |
1086  *     .-----------------------------------------------------------.
1087  *     |  bufsize (u16) : sizeof the BSS Description data          |
1088  *     .-----------------------------------------------------------.
1089  *     |  NumOfSet (u8) : Number of BSS Descs returned             |
1090  *     .-----------------------------------------------------------.
1091  *     |  BSSDescription data (variable, size given in bufsize)    |
1092  *     .-----------------------------------------------------------.
1093  *     |  TLV data (variable, size calculated using header->size,  |
1094  *     |            bufsize and sizeof the fixed fields above)     |
1095  *     .-----------------------------------------------------------.
1096  *
1097  *  @param priv    A pointer to struct lbs_private structure
1098  *  @param resp    A pointer to cmd_ds_command
1099  *
1100  *  @return        0 or -1
1101  */
lbs_ret_80211_scan(struct lbs_private * priv,unsigned long dummy,struct cmd_header * resp)1102 static int lbs_ret_80211_scan(struct lbs_private *priv, unsigned long dummy,
1103 			      struct cmd_header *resp)
1104 {
1105 	struct cmd_ds_802_11_scan_rsp *scanresp = (void *)resp;
1106 	struct bss_descriptor *iter_bss;
1107 	struct bss_descriptor *safe;
1108 	uint8_t *bssinfo;
1109 	uint16_t scanrespsize;
1110 	int bytesleft;
1111 	int idx;
1112 	int tlvbufsize;
1113 	int ret;
1114 
1115 	lbs_deb_enter(LBS_DEB_SCAN);
1116 
1117 	/* Prune old entries from scan table */
1118 	list_for_each_entry_safe (iter_bss, safe, &priv->network_list, list) {
1119 		unsigned long stale_time = iter_bss->last_scanned + DEFAULT_MAX_SCAN_AGE;
1120 		if (time_before(jiffies, stale_time))
1121 			continue;
1122 		list_move_tail (&iter_bss->list, &priv->network_free_list);
1123 		clear_bss_descriptor(iter_bss);
1124 	}
1125 
1126 	if (scanresp->nr_sets > MAX_NETWORK_COUNT) {
1127 		lbs_deb_scan("SCAN_RESP: too many scan results (%d, max %d)\n",
1128 			     scanresp->nr_sets, MAX_NETWORK_COUNT);
1129 		ret = -1;
1130 		goto done;
1131 	}
1132 
1133 	bytesleft = le16_to_cpu(scanresp->bssdescriptsize);
1134 	lbs_deb_scan("SCAN_RESP: bssdescriptsize %d\n", bytesleft);
1135 
1136 	scanrespsize = le16_to_cpu(resp->size);
1137 	lbs_deb_scan("SCAN_RESP: scan results %d\n", scanresp->nr_sets);
1138 
1139 	bssinfo = scanresp->bssdesc_and_tlvbuffer;
1140 
1141 	/* The size of the TLV buffer is equal to the entire command response
1142 	 *   size (scanrespsize) minus the fixed fields (sizeof()'s), the
1143 	 *   BSS Descriptions (bssdescriptsize as bytesLef) and the command
1144 	 *   response header (S_DS_GEN)
1145 	 */
1146 	tlvbufsize = scanrespsize - (bytesleft + sizeof(scanresp->bssdescriptsize)
1147 				     + sizeof(scanresp->nr_sets)
1148 				     + S_DS_GEN);
1149 
1150 	/*
1151 	 *  Process each scan response returned (scanresp->nr_sets). Save
1152 	 *    the information in the newbssentry and then insert into the
1153 	 *    driver scan table either as an update to an existing entry
1154 	 *    or as an addition at the end of the table
1155 	 */
1156 	for (idx = 0; idx < scanresp->nr_sets && bytesleft; idx++) {
1157 		struct bss_descriptor new;
1158 		struct bss_descriptor *found = NULL;
1159 		struct bss_descriptor *oldest = NULL;
1160 
1161 		/* Process the data fields and IEs returned for this BSS */
1162 		memset(&new, 0, sizeof (struct bss_descriptor));
1163 		if (lbs_process_bss(&new, &bssinfo, &bytesleft) != 0) {
1164 			/* error parsing the scan response, skipped */
1165 			lbs_deb_scan("SCAN_RESP: process_bss returned ERROR\n");
1166 			continue;
1167 		}
1168 
1169 		/* Try to find this bss in the scan table */
1170 		list_for_each_entry (iter_bss, &priv->network_list, list) {
1171 			if (is_same_network(iter_bss, &new)) {
1172 				found = iter_bss;
1173 				break;
1174 			}
1175 
1176 			if ((oldest == NULL) ||
1177 			    (iter_bss->last_scanned < oldest->last_scanned))
1178 				oldest = iter_bss;
1179 		}
1180 
1181 		if (found) {
1182 			/* found, clear it */
1183 			clear_bss_descriptor(found);
1184 		} else if (!list_empty(&priv->network_free_list)) {
1185 			/* Pull one from the free list */
1186 			found = list_entry(priv->network_free_list.next,
1187 					   struct bss_descriptor, list);
1188 			list_move_tail(&found->list, &priv->network_list);
1189 		} else if (oldest) {
1190 			/* If there are no more slots, expire the oldest */
1191 			found = oldest;
1192 			clear_bss_descriptor(found);
1193 			list_move_tail(&found->list, &priv->network_list);
1194 		} else {
1195 			continue;
1196 		}
1197 
1198 		lbs_deb_scan("SCAN_RESP: BSSID %pM\n", new.bssid);
1199 
1200 		/* Copy the locally created newbssentry to the scan table */
1201 		memcpy(found, &new, offsetof(struct bss_descriptor, list));
1202 	}
1203 
1204 	ret = 0;
1205 
1206 done:
1207 	lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
1208 	return ret;
1209 }
1210