drivers/net/wireless/libertas/scan.c

   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/kernel.h>
   9 #include <linux/etherdevice.h>
  10 #include <linux/if_arp.h>
  11 #include <asm/unaligned.h>
  12 #include <net/lib80211.h>
  13
  14 #include "host.h"
  15 #include "decl.h"
  16 #include "dev.h"
  17 #include "scan.h"
  18 #include "cmd.h"
  19
  20 //! Approximate amount of data needed to pass a scan result back to iwlist
  21 #define MAX_SCAN_CELL_SIZE  (IW_EV_ADDR_LEN             \
  22                              + IW_ESSID_MAX_SIZE        \
  23                              + IW_EV_UINT_LEN           \
  24                              + IW_EV_FREQ_LEN           \
  25                              + IW_EV_QUAL_LEN           \
  26                              + IW_ESSID_MAX_SIZE        \
  27                              + IW_EV_PARAM_LEN          \
  28                              + 40)      /* 40 for WPAIE */
  29
  30 //! Memory needed to store a max sized channel List TLV for a firmware scan
  31 #define CHAN_TLV_MAX_SIZE  (sizeof(struct mrvl_ie_header)    \
  32                             + (MRVDRV_MAX_CHANNELS_PER_SCAN     \
  33                                * sizeof(struct chanscanparamset)))
  34
  35 //! Memory needed to store a max number/size SSID TLV for a firmware scan
  36 #define SSID_TLV_MAX_SIZE  (1 * sizeof(struct mrvl_ie_ssid_param_set))
  37
  38 //! Maximum memory needed for a cmd_ds_802_11_scan with all TLVs at max
  39 #define MAX_SCAN_CFG_ALLOC (sizeof(struct cmd_ds_802_11_scan)   \
  40                             + CHAN_TLV_MAX_SIZE + SSID_TLV_MAX_SIZE)
  41
  42 //! The maximum number of channels the firmware can scan per command
  43 #define MRVDRV_MAX_CHANNELS_PER_SCAN   14
  44
  45 /**
  46  * @brief Number of channels to scan per firmware scan command issuance.
  47  *
  48  *  Number restricted to prevent hitting the limit on the amount of scan data
  49  *  returned in a single firmware scan command.
  50  */
  51 #define MRVDRV_CHANNELS_PER_SCAN_CMD   4
  52
  53 //! Scan time specified in the channel TLV for each channel for passive scans
  54 #define MRVDRV_PASSIVE_SCAN_CHAN_TIME  100
  55
  56 //! Scan time specified in the channel TLV for each channel for active scans
  57 #define MRVDRV_ACTIVE_SCAN_CHAN_TIME   100
  58
  59 #define DEFAULT_MAX_SCAN_AGE (15 * HZ)
  60
  61 static int lbs_ret_80211_scan(struct lbs_private *priv, unsigned long dummy,
  62                               struct cmd_header *resp);
  63
  64 /*********************************************************************/
  65 /*                                                                   */
  66 /*  Misc helper functions                                            */
  67 /*                                                                   */
  68 /*********************************************************************/
  69
  70 /**
  71  *  @brief Unsets the MSB on basic rates
  72  *
  73  * Scan through an array and unset the MSB for basic data rates.
  74  *
  75  *  @param rates     buffer of data rates
  76  *  @param len       size of buffer
  77  */
  78 static void lbs_unset_basic_rate_flags(u8 *rates, size_t len)
  79 {
  80         int i;
  81
  82         for (i = 0; i < len; i++)
  83                 rates[i] &= 0x7f;
  84 }
  85
  86
  87 static inline void clear_bss_descriptor(struct bss_descriptor *bss)
  88 {
  89         /* Don't blow away ->list, just BSS data */
  90         memset(bss, 0, offsetof(struct bss_descriptor, list));
  91 }
  92
  93 /**
  94  *  @brief Compare two SSIDs
  95  *
  96  *  @param ssid1    A pointer to ssid to compare
  97  *  @param ssid2    A pointer to ssid to compare
  98  *
  99  *  @return         0: ssid is same, otherwise is different
 100  */
 101 int lbs_ssid_cmp(uint8_t *ssid1, uint8_t ssid1_len, uint8_t *ssid2,
 102                  uint8_t ssid2_len)
 103 {
 104         if (ssid1_len != ssid2_len)
 105                 return -1;
 106
 107         return memcmp(ssid1, ssid2, ssid1_len);
 108 }
 109
 110 static inline int is_same_network(struct bss_descriptor *src,
 111                                   struct bss_descriptor *dst)
 112 {
 113         /* A network is only a duplicate if the channel, BSSID, and ESSID
 114          * all match.  We treat all <hidden> with the same BSSID and channel
 115          * as one network */
 116         return ((src->ssid_len == dst->ssid_len) &&
 117                 (src->channel == dst->channel) &&
 118                 !compare_ether_addr(src->bssid, dst->bssid) &&
 119                 !memcmp(src->ssid, dst->ssid, src->ssid_len));
 120 }
 121
 122
 123
 124
 125 /*********************************************************************/
 126 /*                                                                   */
 127 /*  Main scanning support                                            */
 128 /*                                                                   */
 129 /*********************************************************************/
 130
 131 /**
 132  *  @brief Create a channel list for the driver to scan based on region info
 133  *
 134  *  Only used from lbs_scan_setup_scan_config()
 135  *
 136  *  Use the driver region/band information to construct a comprehensive list
 137  *    of channels to scan.  This routine is used for any scan that is not
 138  *    provided a specific channel list to scan.
 139  *
 140  *  @param priv          A pointer to struct lbs_private structure
 141  *  @param scanchanlist  Output parameter: resulting channel list to scan
 142  *
 143  *  @return              void
 144  */
 145 static int lbs_scan_create_channel_list(struct lbs_private *priv,
 146                                         struct chanscanparamset *scanchanlist)
 147 {
 148         struct region_channel *scanregion;
 149         struct chan_freq_power *cfp;
 150         int rgnidx;
 151         int chanidx;
 152         int nextchan;
 153         uint8_t scantype;
 154
 155         chanidx = 0;
 156
 157         /* Set the default scan type to the user specified type, will later
 158          *   be changed to passive on a per channel basis if restricted by
 159          *   regulatory requirements (11d or 11h)
 160          */
 161         scantype = CMD_SCAN_TYPE_ACTIVE;
 162
 163         for (rgnidx = 0; rgnidx < ARRAY_SIZE(priv->region_channel); rgnidx++) {
 164                 if (priv->enable11d && (priv->connect_status != LBS_CONNECTED)
 165                     && (priv->mesh_connect_status != LBS_CONNECTED)) {
 166                         /* Scan all the supported chan for the first scan */
 167                         if (!priv->universal_channel[rgnidx].valid)
 168                                 continue;
 169                         scanregion = &priv->universal_channel[rgnidx];
 170
 171                         /* clear the parsed_region_chan for the first scan */
 172                         memset(&priv->parsed_region_chan, 0x00,
 173                                sizeof(priv->parsed_region_chan));
 174                 } else {
 175                         if (!priv->region_channel[rgnidx].valid)
 176                                 continue;
 177                         scanregion = &priv->region_channel[rgnidx];
 178                 }
 179
 180                 for (nextchan = 0; nextchan < scanregion->nrcfp; nextchan++, chanidx++) {
 181                         struct chanscanparamset *chan = &scanchanlist[chanidx];
 182
 183                         cfp = scanregion->CFP + nextchan;
 184
 185                         if (priv->enable11d)
 186                                 scantype = lbs_get_scan_type_11d(cfp->channel,
 187                                                                  &priv->parsed_region_chan);
 188
 189                         if (scanregion->band == BAND_B || scanregion->band == BAND_G)
 190                                 chan->radiotype = CMD_SCAN_RADIO_TYPE_BG;
 191
 192                         if (scantype == CMD_SCAN_TYPE_PASSIVE) {
 193                                 chan->maxscantime = cpu_to_le16(MRVDRV_PASSIVE_SCAN_CHAN_TIME);
 194                                 chan->chanscanmode.passivescan = 1;
 195                         } else {
 196                                 chan->maxscantime = cpu_to_le16(MRVDRV_ACTIVE_SCAN_CHAN_TIME);
 197                                 chan->chanscanmode.passivescan = 0;
 198                         }
 199
 200                         chan->channumber = cfp->channel;
 201                 }
 202         }
 203         return chanidx;
 204 }
 205
 206 /*
 207  * Add SSID TLV of the form:
 208  *
 209  * TLV-ID SSID     00 00
 210  * length          06 00
 211  * ssid            4d 4e 54 45 53 54
 212  */
 213 static int lbs_scan_add_ssid_tlv(struct lbs_private *priv, u8 *tlv)
 214 {
 215         struct mrvl_ie_ssid_param_set *ssid_tlv = (void *)tlv;
 216
 217         ssid_tlv->header.type = cpu_to_le16(TLV_TYPE_SSID);
 218         ssid_tlv->header.len = cpu_to_le16(priv->scan_ssid_len);
 219         memcpy(ssid_tlv->ssid, priv->scan_ssid, priv->scan_ssid_len);
 220         return sizeof(ssid_tlv->header) + priv->scan_ssid_len;
 221 }
 222
 223 /*
 224  * Add CHANLIST TLV of the form
 225  *
 226  * TLV-ID CHANLIST 01 01
 227  * length          5b 00
 228  * channel 1       00 01 00 00 00 64 00
 229  *   radio type    00
 230  *   channel          01
 231  *   scan type           00
 232  *   min scan time          00 00
 233  *   max scan time                64 00
 234  * channel 2       00 02 00 00 00 64 00
 235  * channel 3       00 03 00 00 00 64 00
 236  * channel 4       00 04 00 00 00 64 00
 237  * channel 5       00 05 00 00 00 64 00
 238  * channel 6       00 06 00 00 00 64 00
 239  * channel 7       00 07 00 00 00 64 00
 240  * channel 8       00 08 00 00 00 64 00
 241  * channel 9       00 09 00 00 00 64 00
 242  * channel 10      00 0a 00 00 00 64 00
 243  * channel 11      00 0b 00 00 00 64 00
 244  * channel 12      00 0c 00 00 00 64 00
 245  * channel 13      00 0d 00 00 00 64 00
 246  *
 247  */
 248 static int lbs_scan_add_chanlist_tlv(uint8_t *tlv,
 249                                      struct chanscanparamset *chan_list,
 250                                      int chan_count)
 251 {
 252         size_t size = sizeof(struct chanscanparamset) *chan_count;
 253         struct mrvl_ie_chanlist_param_set *chan_tlv = (void *)tlv;
 254
 255         chan_tlv->header.type = cpu_to_le16(TLV_TYPE_CHANLIST);
 256         memcpy(chan_tlv->chanscanparam, chan_list, size);
 257         chan_tlv->header.len = cpu_to_le16(size);
 258         return sizeof(chan_tlv->header) + size;
 259 }
 260
 261 /*
 262  * Add RATES TLV of the form
 263  *
 264  * TLV-ID RATES    01 00
 265  * length          0e 00
 266  * rates           82 84 8b 96 0c 12 18 24 30 48 60 6c
 267  *
 268  * The rates are in lbs_bg_rates[], but for the 802.11b
 269  * rates the high bit isn't set.
 270  */
 271 static int lbs_scan_add_rates_tlv(uint8_t *tlv)
 272 {
 273         int i;
 274         struct mrvl_ie_rates_param_set *rate_tlv = (void *)tlv;
 275
 276         rate_tlv->header.type = cpu_to_le16(TLV_TYPE_RATES);
 277         tlv += sizeof(rate_tlv->header);
 278         for (i = 0; i < MAX_RATES; i++) {
 279                 *tlv = lbs_bg_rates[i];
 280                 if (*tlv == 0)
 281                         break;
 282                 /* This code makes sure that the 802.11b rates (1 MBit/s, 2
 283                    MBit/s, 5.5 MBit/s and 11 MBit/s get's the high bit set.
 284                    Note that the values are MBit/s * 2, to mark them as
 285                    basic rates so that the firmware likes it better */
 286                 if (*tlv == 0x02 || *tlv == 0x04 ||
 287                     *tlv == 0x0b || *tlv == 0x16)
 288                         *tlv |= 0x80;
 289                 tlv++;
 290         }
 291         rate_tlv->header.len = cpu_to_le16(i);
 292         return sizeof(rate_tlv->header) + i;
 293 }
 294
 295 /*
 296  * Generate the CMD_802_11_SCAN command with the proper tlv
 297  * for a bunch of channels.
 298  */
 299 static int lbs_do_scan(struct lbs_private *priv, uint8_t bsstype,
 300                        struct chanscanparamset *chan_list, int chan_count)
 301 {
 302         int ret = -ENOMEM;
 303         struct cmd_ds_802_11_scan *scan_cmd;
 304         uint8_t *tlv;   /* pointer into our current, growing TLV storage area */
 305
 306         lbs_deb_enter_args(LBS_DEB_SCAN, "bsstype %d, chanlist[].chan %d, chan_count %d",
 307                 bsstype, chan_list ? chan_list[0].channumber : -1,
 308                 chan_count);
 309
 310         /* create the fixed part for scan command */
 311         scan_cmd = kzalloc(MAX_SCAN_CFG_ALLOC, GFP_KERNEL);
 312         if (scan_cmd == NULL)
 313                 goto out;
 314
 315         tlv = scan_cmd->tlvbuffer;
 316         /* TODO: do we need to scan for a specific BSSID?
 317         memcpy(scan_cmd->bssid, priv->scan_bssid, ETH_ALEN); */
 318         scan_cmd->bsstype = bsstype;
 319
 320         /* add TLVs */
 321         if (priv->scan_ssid_len)
 322                 tlv += lbs_scan_add_ssid_tlv(priv, tlv);
 323         if (chan_list && chan_count)
 324                 tlv += lbs_scan_add_chanlist_tlv(tlv, chan_list, chan_count);
 325         tlv += lbs_scan_add_rates_tlv(tlv);
 326
 327         /* This is the final data we are about to send */
 328         scan_cmd->hdr.size = cpu_to_le16(tlv - (uint8_t *)scan_cmd);
 329         lbs_deb_hex(LBS_DEB_SCAN, "SCAN_CMD", (void *)scan_cmd,
 330                     sizeof(*scan_cmd));
 331         lbs_deb_hex(LBS_DEB_SCAN, "SCAN_TLV", scan_cmd->tlvbuffer,
 332                     tlv - scan_cmd->tlvbuffer);
 333
 334         ret = __lbs_cmd(priv, CMD_802_11_SCAN, &scan_cmd->hdr,
 335                         le16_to_cpu(scan_cmd->hdr.size),
 336                         lbs_ret_80211_scan, 0);
 337
 338 out:
 339         kfree(scan_cmd);
 340         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
 341         return ret;
 342 }
 343
 344 /**
 345  *  @brief Internal function used to start a scan based on an input config
 346  *
 347  *  Use the input user scan configuration information when provided in
 348  *    order to send the appropriate scan commands to firmware to populate or
 349  *    update the internal driver scan table
 350  *
 351  *  @param priv          A pointer to struct lbs_private structure
 352  *  @param full_scan     Do a full-scan (blocking)
 353  *
 354  *  @return              0 or < 0 if error
 355  */
 356 int lbs_scan_networks(struct lbs_private *priv, int full_scan)
 357 {
 358         int ret = -ENOMEM;
 359         struct chanscanparamset *chan_list;
 360         struct chanscanparamset *curr_chans;
 361         int chan_count;
 362         uint8_t bsstype = CMD_BSS_TYPE_ANY;
 363         int numchannels = MRVDRV_CHANNELS_PER_SCAN_CMD;
 364         union iwreq_data wrqu;
 365 #ifdef CONFIG_LIBERTAS_DEBUG
 366         struct bss_descriptor *iter;
 367         int i = 0;
 368         DECLARE_SSID_BUF(ssid);
 369 #endif
 370
 371         lbs_deb_enter_args(LBS_DEB_SCAN, "full_scan %d", full_scan);
 372
 373         /* Cancel any partial outstanding partial scans if this scan
 374          * is a full scan.
 375          */
 376         if (full_scan && delayed_work_pending(&priv->scan_work))
 377                 cancel_delayed_work(&priv->scan_work);
 378
 379         /* User-specified bsstype or channel list
 380         TODO: this can be implemented if some user-space application
 381         need the feature. Formerly, it was accessible from debugfs,
 382         but then nowhere used.
 383         if (user_cfg) {
 384                 if (user_cfg->bsstype)
 385                 bsstype = user_cfg->bsstype;
 386         } */
 387
 388         lbs_deb_scan("numchannels %d, bsstype %d\n", numchannels, bsstype);
 389
 390         /* Create list of channels to scan */
 391         chan_list = kzalloc(sizeof(struct chanscanparamset) *
 392                             LBS_IOCTL_USER_SCAN_CHAN_MAX, GFP_KERNEL);
 393         if (!chan_list) {
 394                 lbs_pr_alert("SCAN: chan_list empty\n");
 395                 goto out;
 396         }
 397
 398         /* We want to scan all channels */
 399         chan_count = lbs_scan_create_channel_list(priv, chan_list);
 400
 401         netif_stop_queue(priv->dev);
 402         netif_carrier_off(priv->dev);
 403         if (priv->mesh_dev) {
 404                 netif_stop_queue(priv->mesh_dev);
 405                 netif_carrier_off(priv->mesh_dev);
 406         }
 407
 408         /* Prepare to continue an interrupted scan */
 409         lbs_deb_scan("chan_count %d, scan_channel %d\n",
 410                      chan_count, priv->scan_channel);
 411         curr_chans = chan_list;
 412         /* advance channel list by already-scanned-channels */
 413         if (priv->scan_channel > 0) {
 414                 curr_chans += priv->scan_channel;
 415                 chan_count -= priv->scan_channel;
 416         }
 417
 418         /* Send scan command(s)
 419          * numchannels contains the number of channels we should maximally scan
 420          * chan_count is the total number of channels to scan
 421          */
 422
 423         while (chan_count) {
 424                 int to_scan = min(numchannels, chan_count);
 425                 lbs_deb_scan("scanning %d of %d channels\n",
 426                              to_scan, chan_count);
 427                 ret = lbs_do_scan(priv, bsstype, curr_chans,
 428                                   to_scan);
 429                 if (ret) {
 430                         lbs_pr_err("SCAN_CMD failed\n");
 431                         goto out2;
 432                 }
 433                 curr_chans += to_scan;
 434                 chan_count -= to_scan;
 435
 436                 /* somehow schedule the next part of the scan */
 437                 if (chan_count && !full_scan &&
 438                     !priv->surpriseremoved) {
 439                         /* -1 marks just that we're currently scanning */
 440                         if (priv->scan_channel < 0)
 441                                 priv->scan_channel = to_scan;
 442                         else
 443                                 priv->scan_channel += to_scan;
 444                         cancel_delayed_work(&priv->scan_work);
 445                         queue_delayed_work(priv->work_thread, &priv->scan_work,
 446                                            msecs_to_jiffies(300));
 447                         /* skip over GIWSCAN event */
 448                         goto out;
 449                 }
 450
 451         }
 452         memset(&wrqu, 0, sizeof(union iwreq_data));
 453         wireless_send_event(priv->dev, SIOCGIWSCAN, &wrqu, NULL);
 454
 455 #ifdef CONFIG_LIBERTAS_DEBUG
 456         /* Dump the scan table */
 457         mutex_lock(&priv->lock);
 458         lbs_deb_scan("scan table:\n");
 459         list_for_each_entry(iter, &priv->network_list, list)
 460                 lbs_deb_scan("%02d: BSSID %pM, RSSI %d, SSID '%s'\n",
 461                              i++, iter->bssid, iter->rssi,
 462                              print_ssid(ssid, iter->ssid, iter->ssid_len));
 463         mutex_unlock(&priv->lock);
 464 #endif
 465
 466 out2:
 467         priv->scan_channel = 0;
 468
 469 out:
 470         if (priv->connect_status == LBS_CONNECTED) {
 471                 netif_carrier_on(priv->dev);
 472                 if (!priv->tx_pending_len)
 473                         netif_wake_queue(priv->dev);
 474         }
 475         if (priv->mesh_dev && (priv->mesh_connect_status == LBS_CONNECTED)) {
 476                 netif_carrier_on(priv->mesh_dev);
 477                 if (!priv->tx_pending_len)
 478                         netif_wake_queue(priv->mesh_dev);
 479         }
 480         kfree(chan_list);
 481
 482         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
 483         return ret;
 484 }
 485
 486 void lbs_scan_worker(struct work_struct *work)
 487 {
 488         struct lbs_private *priv =
 489                 container_of(work, struct lbs_private, scan_work.work);
 490
 491         lbs_deb_enter(LBS_DEB_SCAN);
 492         lbs_scan_networks(priv, 0);
 493         lbs_deb_leave(LBS_DEB_SCAN);
 494 }
 495
 496
 497 /*********************************************************************/
 498 /*                                                                   */
 499 /*  Result interpretation                                            */
 500 /*                                                                   */
 501 /*********************************************************************/
 502
 503 /**
 504  *  @brief Interpret a BSS scan response returned from the firmware
 505  *
 506  *  Parse the various fixed fields and IEs passed back for a a BSS probe
 507  *  response or beacon from the scan command.  Record information as needed
 508  *  in the scan table struct bss_descriptor for that entry.
 509  *
 510  *  @param bss  Output parameter: Pointer to the BSS Entry
 511  *
 512  *  @return             0 or -1
 513  */
 514 static int lbs_process_bss(struct bss_descriptor *bss,
 515                            uint8_t **pbeaconinfo, int *bytesleft)
 516 {
 517         struct ieee_ie_fh_param_set *fh;
 518         struct ieee_ie_ds_param_set *ds;
 519         struct ieee_ie_cf_param_set *cf;
 520         struct ieee_ie_ibss_param_set *ibss;
 521         DECLARE_SSID_BUF(ssid);
 522         struct ieee_ie_country_info_set *pcountryinfo;
 523         uint8_t *pos, *end, *p;
 524         uint8_t n_ex_rates = 0, got_basic_rates = 0, n_basic_rates = 0;
 525         uint16_t beaconsize = 0;
 526         int ret;
 527
 528         lbs_deb_enter(LBS_DEB_SCAN);
 529
 530         if (*bytesleft >= sizeof(beaconsize)) {
 531                 /* Extract & convert beacon size from the command buffer */
 532                 beaconsize = get_unaligned_le16(*pbeaconinfo);
 533                 *bytesleft -= sizeof(beaconsize);
 534                 *pbeaconinfo += sizeof(beaconsize);
 535         }
 536
 537         if (beaconsize == 0 || beaconsize > *bytesleft) {
 538                 *pbeaconinfo += *bytesleft;
 539                 *bytesleft = 0;
 540                 ret = -1;
 541                 goto done;
 542         }
 543
 544         /* Initialize the current working beacon pointer for this BSS iteration */
 545         pos = *pbeaconinfo;
 546         end = pos + beaconsize;
 547
 548         /* Advance the return beacon pointer past the current beacon */
 549         *pbeaconinfo += beaconsize;
 550         *bytesleft -= beaconsize;
 551
 552         memcpy(bss->bssid, pos, ETH_ALEN);
 553         lbs_deb_scan("process_bss: BSSID %pM\n", bss->bssid);
 554         pos += ETH_ALEN;
 555
 556         if ((end - pos) < 12) {
 557                 lbs_deb_scan("process_bss: Not enough bytes left\n");
 558                 ret = -1;
 559                 goto done;
 560         }
 561
 562         /*
 563          * next 4 fields are RSSI, time stamp, beacon interval,
 564          *   and capability information
 565          */
 566
 567         /* RSSI is 1 byte long */
 568         bss->rssi = *pos;
 569         lbs_deb_scan("process_bss: RSSI %d\n", *pos);
 570         pos++;
 571
 572         /* time stamp is 8 bytes long */
 573         pos += 8;
 574
 575         /* beacon interval is 2 bytes long */
 576         bss->beaconperiod = get_unaligned_le16(pos);
 577         pos += 2;
 578
 579         /* capability information is 2 bytes long */
 580         bss->capability = get_unaligned_le16(pos);
 581         lbs_deb_scan("process_bss: capabilities 0x%04x\n", bss->capability);
 582         pos += 2;
 583
 584         if (bss->capability & WLAN_CAPABILITY_PRIVACY)
 585                 lbs_deb_scan("process_bss: WEP enabled\n");
 586         if (bss->capability & WLAN_CAPABILITY_IBSS)
 587                 bss->mode = IW_MODE_ADHOC;
 588         else
 589                 bss->mode = IW_MODE_INFRA;
 590
 591         /* rest of the current buffer are IE's */
 592         lbs_deb_scan("process_bss: IE len %zd\n", end - pos);
 593         lbs_deb_hex(LBS_DEB_SCAN, "process_bss: IE info", pos, end - pos);
 594
 595         /* process variable IE */
 596         while (pos <= end - 2) {
 597                 if (pos + pos[1] > end) {
 598                         lbs_deb_scan("process_bss: error in processing IE, "
 599                                      "bytes left < IE length\n");
 600                         break;
 601                 }
 602
 603                 switch (pos[0]) {
 604                 case WLAN_EID_SSID:
 605                         bss->ssid_len = min_t(int, IEEE80211_MAX_SSID_LEN, pos[1]);
 606                         memcpy(bss->ssid, pos + 2, bss->ssid_len);
 607                         lbs_deb_scan("got SSID IE: '%s', len %u\n",
 608                                      print_ssid(ssid, bss->ssid, bss->ssid_len),
 609                                      bss->ssid_len);
 610                         break;
 611
 612                 case WLAN_EID_SUPP_RATES:
 613                         n_basic_rates = min_t(uint8_t, MAX_RATES, pos[1]);
 614                         memcpy(bss->rates, pos + 2, n_basic_rates);
 615                         got_basic_rates = 1;
 616                         lbs_deb_scan("got RATES IE\n");
 617                         break;
 618
 619                 case WLAN_EID_FH_PARAMS:
 620                         fh = (struct ieee_ie_fh_param_set *) pos;
 621                         memcpy(&bss->phy.fh, fh, sizeof(*fh));
 622                         lbs_deb_scan("got FH IE\n");
 623                         break;
 624
 625                 case WLAN_EID_DS_PARAMS:
 626                         ds = (struct ieee_ie_ds_param_set *) pos;
 627                         bss->channel = ds->channel;
 628                         memcpy(&bss->phy.ds, ds, sizeof(*ds));
 629                         lbs_deb_scan("got DS IE, channel %d\n", bss->channel);
 630                         break;
 631
 632                 case WLAN_EID_CF_PARAMS:
 633                         cf = (struct ieee_ie_cf_param_set *) pos;
 634                         memcpy(&bss->ss.cf, cf, sizeof(*cf));
 635                         lbs_deb_scan("got CF IE\n");
 636                         break;
 637
 638                 case WLAN_EID_IBSS_PARAMS:
 639                         ibss = (struct ieee_ie_ibss_param_set *) pos;
 640                         bss->atimwindow = ibss->atimwindow;
 641                         memcpy(&bss->ss.ibss, ibss, sizeof(*ibss));
 642                         lbs_deb_scan("got IBSS IE\n");
 643                         break;
 644
 645                 case WLAN_EID_COUNTRY:
 646                         pcountryinfo = (struct ieee_ie_country_info_set *) pos;
 647                         lbs_deb_scan("got COUNTRY IE\n");
 648                         if (pcountryinfo->header.len < sizeof(pcountryinfo->countrycode)
 649                             || pcountryinfo->header.len > 254) {
 650                                 lbs_deb_scan("%s: 11D- Err CountryInfo len %d, min %zd, max 254\n",
 651                                              __func__,
 652                                              pcountryinfo->header.len,
 653                                              sizeof(pcountryinfo->countrycode));
 654                                 ret = -1;
 655                                 goto done;
 656                         }
 657
 658                         memcpy(&bss->countryinfo, pcountryinfo,
 659                                 pcountryinfo->header.len + 2);
 660                         lbs_deb_hex(LBS_DEB_SCAN, "process_bss: 11d countryinfo",
 661                                     (uint8_t *) pcountryinfo,
 662                                     (int) (pcountryinfo->header.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[5] == 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  */
 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
 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; j < ARRAY_SIZE(bss->rates) && bss->rates[j]; 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  */
 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  */
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  */
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 = get_unaligned_le16(&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 }