SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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->region_channel[rgnidx].valid)
 165                         continue;
 166                 scanregion = &priv->region_channel[rgnidx];
 167
 168                 for (nextchan = 0; nextchan < scanregion->nrcfp; nextchan++, chanidx++) {
 169                         struct chanscanparamset *chan = &scanchanlist[chanidx];
 170
 171                         cfp = scanregion->CFP + nextchan;
 172
 173                         if (scanregion->band == BAND_B || scanregion->band == BAND_G)
 174                                 chan->radiotype = CMD_SCAN_RADIO_TYPE_BG;
 175
 176                         if (scantype == CMD_SCAN_TYPE_PASSIVE) {
 177                                 chan->maxscantime = cpu_to_le16(MRVDRV_PASSIVE_SCAN_CHAN_TIME);
 178                                 chan->chanscanmode.passivescan = 1;
 179                         } else {
 180                                 chan->maxscantime = cpu_to_le16(MRVDRV_ACTIVE_SCAN_CHAN_TIME);
 181                                 chan->chanscanmode.passivescan = 0;
 182                         }
 183
 184                         chan->channumber = cfp->channel;
 185                 }
 186         }
 187         return chanidx;
 188 }
 189
 190 /*
 191  * Add SSID TLV of the form:
 192  *
 193  * TLV-ID SSID     00 00
 194  * length          06 00
 195  * ssid            4d 4e 54 45 53 54
 196  */
 197 static int lbs_scan_add_ssid_tlv(struct lbs_private *priv, u8 *tlv)
 198 {
 199         struct mrvl_ie_ssid_param_set *ssid_tlv = (void *)tlv;
 200
 201         ssid_tlv->header.type = cpu_to_le16(TLV_TYPE_SSID);
 202         ssid_tlv->header.len = cpu_to_le16(priv->scan_ssid_len);
 203         memcpy(ssid_tlv->ssid, priv->scan_ssid, priv->scan_ssid_len);
 204         return sizeof(ssid_tlv->header) + priv->scan_ssid_len;
 205 }
 206
 207 /*
 208  * Add CHANLIST TLV of the form
 209  *
 210  * TLV-ID CHANLIST 01 01
 211  * length          5b 00
 212  * channel 1       00 01 00 00 00 64 00
 213  *   radio type    00
 214  *   channel          01
 215  *   scan type           00
 216  *   min scan time          00 00
 217  *   max scan time                64 00
 218  * channel 2       00 02 00 00 00 64 00
 219  * channel 3       00 03 00 00 00 64 00
 220  * channel 4       00 04 00 00 00 64 00
 221  * channel 5       00 05 00 00 00 64 00
 222  * channel 6       00 06 00 00 00 64 00
 223  * channel 7       00 07 00 00 00 64 00
 224  * channel 8       00 08 00 00 00 64 00
 225  * channel 9       00 09 00 00 00 64 00
 226  * channel 10      00 0a 00 00 00 64 00
 227  * channel 11      00 0b 00 00 00 64 00
 228  * channel 12      00 0c 00 00 00 64 00
 229  * channel 13      00 0d 00 00 00 64 00
 230  *
 231  */
 232 static int lbs_scan_add_chanlist_tlv(uint8_t *tlv,
 233                                      struct chanscanparamset *chan_list,
 234                                      int chan_count)
 235 {
 236         size_t size = sizeof(struct chanscanparamset) *chan_count;
 237         struct mrvl_ie_chanlist_param_set *chan_tlv = (void *)tlv;
 238
 239         chan_tlv->header.type = cpu_to_le16(TLV_TYPE_CHANLIST);
 240         memcpy(chan_tlv->chanscanparam, chan_list, size);
 241         chan_tlv->header.len = cpu_to_le16(size);
 242         return sizeof(chan_tlv->header) + size;
 243 }
 244
 245 /*
 246  * Add RATES TLV of the form
 247  *
 248  * TLV-ID RATES    01 00
 249  * length          0e 00
 250  * rates           82 84 8b 96 0c 12 18 24 30 48 60 6c
 251  *
 252  * The rates are in lbs_bg_rates[], but for the 802.11b
 253  * rates the high bit isn't set.
 254  */
 255 static int lbs_scan_add_rates_tlv(uint8_t *tlv)
 256 {
 257         int i;
 258         struct mrvl_ie_rates_param_set *rate_tlv = (void *)tlv;
 259
 260         rate_tlv->header.type = cpu_to_le16(TLV_TYPE_RATES);
 261         tlv += sizeof(rate_tlv->header);
 262         for (i = 0; i < MAX_RATES; i++) {
 263                 *tlv = lbs_bg_rates[i];
 264                 if (*tlv == 0)
 265                         break;
 266                 /* This code makes sure that the 802.11b rates (1 MBit/s, 2
 267                    MBit/s, 5.5 MBit/s and 11 MBit/s get's the high bit set.
 268                    Note that the values are MBit/s * 2, to mark them as
 269                    basic rates so that the firmware likes it better */
 270                 if (*tlv == 0x02 || *tlv == 0x04 ||
 271                     *tlv == 0x0b || *tlv == 0x16)
 272                         *tlv |= 0x80;
 273                 tlv++;
 274         }
 275         rate_tlv->header.len = cpu_to_le16(i);
 276         return sizeof(rate_tlv->header) + i;
 277 }
 278
 279 /*
 280  * Generate the CMD_802_11_SCAN command with the proper tlv
 281  * for a bunch of channels.
 282  */
 283 static int lbs_do_scan(struct lbs_private *priv, uint8_t bsstype,
 284                        struct chanscanparamset *chan_list, int chan_count)
 285 {
 286         int ret = -ENOMEM;
 287         struct cmd_ds_802_11_scan *scan_cmd;
 288         uint8_t *tlv;   /* pointer into our current, growing TLV storage area */
 289
 290         lbs_deb_enter_args(LBS_DEB_SCAN, "bsstype %d, chanlist[].chan %d, chan_count %d",
 291                 bsstype, chan_list ? chan_list[0].channumber : -1,
 292                 chan_count);
 293
 294         /* create the fixed part for scan command */
 295         scan_cmd = kzalloc(MAX_SCAN_CFG_ALLOC, GFP_KERNEL);
 296         if (scan_cmd == NULL)
 297                 goto out;
 298
 299         tlv = scan_cmd->tlvbuffer;
 300         /* TODO: do we need to scan for a specific BSSID?
 301         memcpy(scan_cmd->bssid, priv->scan_bssid, ETH_ALEN); */
 302         scan_cmd->bsstype = bsstype;
 303
 304         /* add TLVs */
 305         if (priv->scan_ssid_len)
 306                 tlv += lbs_scan_add_ssid_tlv(priv, tlv);
 307         if (chan_list && chan_count)
 308                 tlv += lbs_scan_add_chanlist_tlv(tlv, chan_list, chan_count);
 309         tlv += lbs_scan_add_rates_tlv(tlv);
 310
 311         /* This is the final data we are about to send */
 312         scan_cmd->hdr.size = cpu_to_le16(tlv - (uint8_t *)scan_cmd);
 313         lbs_deb_hex(LBS_DEB_SCAN, "SCAN_CMD", (void *)scan_cmd,
 314                     sizeof(*scan_cmd));
 315         lbs_deb_hex(LBS_DEB_SCAN, "SCAN_TLV", scan_cmd->tlvbuffer,
 316                     tlv - scan_cmd->tlvbuffer);
 317
 318         ret = __lbs_cmd(priv, CMD_802_11_SCAN, &scan_cmd->hdr,
 319                         le16_to_cpu(scan_cmd->hdr.size),
 320                         lbs_ret_80211_scan, 0);
 321
 322 out:
 323         kfree(scan_cmd);
 324         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
 325         return ret;
 326 }
 327
 328 /**
 329  *  @brief Internal function used to start a scan based on an input config
 330  *
 331  *  Use the input user scan configuration information when provided in
 332  *    order to send the appropriate scan commands to firmware to populate or
 333  *    update the internal driver scan table
 334  *
 335  *  @param priv          A pointer to struct lbs_private structure
 336  *  @param full_scan     Do a full-scan (blocking)
 337  *
 338  *  @return              0 or < 0 if error
 339  */
 340 int lbs_scan_networks(struct lbs_private *priv, int full_scan)
 341 {
 342         int ret = -ENOMEM;
 343         struct chanscanparamset *chan_list;
 344         struct chanscanparamset *curr_chans;
 345         int chan_count;
 346         uint8_t bsstype = CMD_BSS_TYPE_ANY;
 347         int numchannels = MRVDRV_CHANNELS_PER_SCAN_CMD;
 348         union iwreq_data wrqu;
 349 #ifdef CONFIG_LIBERTAS_DEBUG
 350         struct bss_descriptor *iter;
 351         int i = 0;
 352         DECLARE_SSID_BUF(ssid);
 353 #endif
 354
 355         lbs_deb_enter_args(LBS_DEB_SCAN, "full_scan %d", full_scan);
 356
 357         /* Cancel any partial outstanding partial scans if this scan
 358          * is a full scan.
 359          */
 360         if (full_scan && delayed_work_pending(&priv->scan_work))
 361                 cancel_delayed_work(&priv->scan_work);
 362
 363         /* User-specified bsstype or channel list
 364         TODO: this can be implemented if some user-space application
 365         need the feature. Formerly, it was accessible from debugfs,
 366         but then nowhere used.
 367         if (user_cfg) {
 368                 if (user_cfg->bsstype)
 369                 bsstype = user_cfg->bsstype;
 370         } */
 371
 372         lbs_deb_scan("numchannels %d, bsstype %d\n", numchannels, bsstype);
 373
 374         /* Create list of channels to scan */
 375         chan_list = kzalloc(sizeof(struct chanscanparamset) *
 376                             LBS_IOCTL_USER_SCAN_CHAN_MAX, GFP_KERNEL);
 377         if (!chan_list) {
 378                 lbs_pr_alert("SCAN: chan_list empty\n");
 379                 goto out;
 380         }
 381
 382         /* We want to scan all channels */
 383         chan_count = lbs_scan_create_channel_list(priv, chan_list);
 384
 385         netif_stop_queue(priv->dev);
 386         netif_carrier_off(priv->dev);
 387         if (priv->mesh_dev) {
 388                 netif_stop_queue(priv->mesh_dev);
 389                 netif_carrier_off(priv->mesh_dev);
 390         }
 391
 392         /* Prepare to continue an interrupted scan */
 393         lbs_deb_scan("chan_count %d, scan_channel %d\n",
 394                      chan_count, priv->scan_channel);
 395         curr_chans = chan_list;
 396         /* advance channel list by already-scanned-channels */
 397         if (priv->scan_channel > 0) {
 398                 curr_chans += priv->scan_channel;
 399                 chan_count -= priv->scan_channel;
 400         }
 401
 402         /* Send scan command(s)
 403          * numchannels contains the number of channels we should maximally scan
 404          * chan_count is the total number of channels to scan
 405          */
 406
 407         while (chan_count) {
 408                 int to_scan = min(numchannels, chan_count);
 409                 lbs_deb_scan("scanning %d of %d channels\n",
 410                              to_scan, chan_count);
 411                 ret = lbs_do_scan(priv, bsstype, curr_chans,
 412                                   to_scan);
 413                 if (ret) {
 414                         lbs_pr_err("SCAN_CMD failed\n");
 415                         goto out2;
 416                 }
 417                 curr_chans += to_scan;
 418                 chan_count -= to_scan;
 419
 420                 /* somehow schedule the next part of the scan */
 421                 if (chan_count && !full_scan &&
 422                     !priv->surpriseremoved) {
 423                         /* -1 marks just that we're currently scanning */
 424                         if (priv->scan_channel < 0)
 425                                 priv->scan_channel = to_scan;
 426                         else
 427                                 priv->scan_channel += to_scan;
 428                         cancel_delayed_work(&priv->scan_work);
 429                         queue_delayed_work(priv->work_thread, &priv->scan_work,
 430                                            msecs_to_jiffies(300));
 431                         /* skip over GIWSCAN event */
 432                         goto out;
 433                 }
 434
 435         }
 436         memset(&wrqu, 0, sizeof(union iwreq_data));
 437         wireless_send_event(priv->dev, SIOCGIWSCAN, &wrqu, NULL);
 438
 439 #ifdef CONFIG_LIBERTAS_DEBUG
 440         /* Dump the scan table */
 441         mutex_lock(&priv->lock);
 442         lbs_deb_scan("scan table:\n");
 443         list_for_each_entry(iter, &priv->network_list, list)
 444                 lbs_deb_scan("%02d: BSSID %pM, RSSI %d, SSID '%s'\n",
 445                              i++, iter->bssid, iter->rssi,
 446                              print_ssid(ssid, iter->ssid, iter->ssid_len));
 447         mutex_unlock(&priv->lock);
 448 #endif
 449
 450 out2:
 451         priv->scan_channel = 0;
 452
 453 out:
 454         if (priv->connect_status == LBS_CONNECTED) {
 455                 netif_carrier_on(priv->dev);
 456                 if (!priv->tx_pending_len)
 457                         netif_wake_queue(priv->dev);
 458         }
 459         if (priv->mesh_dev && (priv->mesh_connect_status == LBS_CONNECTED)) {
 460                 netif_carrier_on(priv->mesh_dev);
 461                 if (!priv->tx_pending_len)
 462                         netif_wake_queue(priv->mesh_dev);
 463         }
 464         kfree(chan_list);
 465
 466         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
 467         return ret;
 468 }
 469
 470 void lbs_scan_worker(struct work_struct *work)
 471 {
 472         struct lbs_private *priv =
 473                 container_of(work, struct lbs_private, scan_work.work);
 474
 475         lbs_deb_enter(LBS_DEB_SCAN);
 476         lbs_scan_networks(priv, 0);
 477         lbs_deb_leave(LBS_DEB_SCAN);
 478 }
 479
 480
 481 /*********************************************************************/
 482 /*                                                                   */
 483 /*  Result interpretation                                            */
 484 /*                                                                   */
 485 /*********************************************************************/
 486
 487 /**
 488  *  @brief Interpret a BSS scan response returned from the firmware
 489  *
 490  *  Parse the various fixed fields and IEs passed back for a a BSS probe
 491  *  response or beacon from the scan command.  Record information as needed
 492  *  in the scan table struct bss_descriptor for that entry.
 493  *
 494  *  @param bss  Output parameter: Pointer to the BSS Entry
 495  *
 496  *  @return             0 or -1
 497  */
 498 static int lbs_process_bss(struct bss_descriptor *bss,
 499                            uint8_t **pbeaconinfo, int *bytesleft)
 500 {
 501         struct ieee_ie_fh_param_set *fh;
 502         struct ieee_ie_ds_param_set *ds;
 503         struct ieee_ie_cf_param_set *cf;
 504         struct ieee_ie_ibss_param_set *ibss;
 505         DECLARE_SSID_BUF(ssid);
 506         struct ieee_ie_country_info_set *pcountryinfo;
 507         uint8_t *pos, *end, *p;
 508         uint8_t n_ex_rates = 0, got_basic_rates = 0, n_basic_rates = 0;
 509         uint16_t beaconsize = 0;
 510         int ret;
 511
 512         lbs_deb_enter(LBS_DEB_SCAN);
 513
 514         if (*bytesleft >= sizeof(beaconsize)) {
 515                 /* Extract & convert beacon size from the command buffer */
 516                 beaconsize = get_unaligned_le16(*pbeaconinfo);
 517                 *bytesleft -= sizeof(beaconsize);
 518                 *pbeaconinfo += sizeof(beaconsize);
 519         }
 520
 521         if (beaconsize == 0 || beaconsize > *bytesleft) {
 522                 *pbeaconinfo += *bytesleft;
 523                 *bytesleft = 0;
 524                 ret = -1;
 525                 goto done;
 526         }
 527
 528         /* Initialize the current working beacon pointer for this BSS iteration */
 529         pos = *pbeaconinfo;
 530         end = pos + beaconsize;
 531
 532         /* Advance the return beacon pointer past the current beacon */
 533         *pbeaconinfo += beaconsize;
 534         *bytesleft -= beaconsize;
 535
 536         memcpy(bss->bssid, pos, ETH_ALEN);
 537         lbs_deb_scan("process_bss: BSSID %pM\n", bss->bssid);
 538         pos += ETH_ALEN;
 539
 540         if ((end - pos) < 12) {
 541                 lbs_deb_scan("process_bss: Not enough bytes left\n");
 542                 ret = -1;
 543                 goto done;
 544         }
 545
 546         /*
 547          * next 4 fields are RSSI, time stamp, beacon interval,
 548          *   and capability information
 549          */
 550
 551         /* RSSI is 1 byte long */
 552         bss->rssi = *pos;
 553         lbs_deb_scan("process_bss: RSSI %d\n", *pos);
 554         pos++;
 555
 556         /* time stamp is 8 bytes long */
 557         pos += 8;
 558
 559         /* beacon interval is 2 bytes long */
 560         bss->beaconperiod = get_unaligned_le16(pos);
 561         pos += 2;
 562
 563         /* capability information is 2 bytes long */
 564         bss->capability = get_unaligned_le16(pos);
 565         lbs_deb_scan("process_bss: capabilities 0x%04x\n", bss->capability);
 566         pos += 2;
 567
 568         if (bss->capability & WLAN_CAPABILITY_PRIVACY)
 569                 lbs_deb_scan("process_bss: WEP enabled\n");
 570         if (bss->capability & WLAN_CAPABILITY_IBSS)
 571                 bss->mode = IW_MODE_ADHOC;
 572         else
 573                 bss->mode = IW_MODE_INFRA;
 574
 575         /* rest of the current buffer are IE's */
 576         lbs_deb_scan("process_bss: IE len %zd\n", end - pos);
 577         lbs_deb_hex(LBS_DEB_SCAN, "process_bss: IE info", pos, end - pos);
 578
 579         /* process variable IE */
 580         while (pos <= end - 2) {
 581                 if (pos + pos[1] > end) {
 582                         lbs_deb_scan("process_bss: error in processing IE, "
 583                                      "bytes left < IE length\n");
 584                         break;
 585                 }
 586
 587                 switch (pos[0]) {
 588                 case WLAN_EID_SSID:
 589                         bss->ssid_len = min_t(int, IEEE80211_MAX_SSID_LEN, pos[1]);
 590                         memcpy(bss->ssid, pos + 2, bss->ssid_len);
 591                         lbs_deb_scan("got SSID IE: '%s', len %u\n",
 592                                      print_ssid(ssid, bss->ssid, bss->ssid_len),
 593                                      bss->ssid_len);
 594                         break;
 595
 596                 case WLAN_EID_SUPP_RATES:
 597                         n_basic_rates = min_t(uint8_t, MAX_RATES, pos[1]);
 598                         memcpy(bss->rates, pos + 2, n_basic_rates);
 599                         got_basic_rates = 1;
 600                         lbs_deb_scan("got RATES IE\n");
 601                         break;
 602
 603                 case WLAN_EID_FH_PARAMS:
 604                         fh = (struct ieee_ie_fh_param_set *) pos;
 605                         memcpy(&bss->phy.fh, fh, sizeof(*fh));
 606                         lbs_deb_scan("got FH IE\n");
 607                         break;
 608
 609                 case WLAN_EID_DS_PARAMS:
 610                         ds = (struct ieee_ie_ds_param_set *) pos;
 611                         bss->channel = ds->channel;
 612                         memcpy(&bss->phy.ds, ds, sizeof(*ds));
 613                         lbs_deb_scan("got DS IE, channel %d\n", bss->channel);
 614                         break;
 615
 616                 case WLAN_EID_CF_PARAMS:
 617                         cf = (struct ieee_ie_cf_param_set *) pos;
 618                         memcpy(&bss->ss.cf, cf, sizeof(*cf));
 619                         lbs_deb_scan("got CF IE\n");
 620                         break;
 621
 622                 case WLAN_EID_IBSS_PARAMS:
 623                         ibss = (struct ieee_ie_ibss_param_set *) pos;
 624                         bss->atimwindow = ibss->atimwindow;
 625                         memcpy(&bss->ss.ibss, ibss, sizeof(*ibss));
 626                         lbs_deb_scan("got IBSS IE\n");
 627                         break;
 628
 629                 case WLAN_EID_COUNTRY:
 630                         pcountryinfo = (struct ieee_ie_country_info_set *) pos;
 631                         lbs_deb_scan("got COUNTRY IE\n");
 632                         if (pcountryinfo->header.len < sizeof(pcountryinfo->countrycode)
 633                             || pcountryinfo->header.len > 254) {
 634                                 lbs_deb_scan("%s: 11D- Err CountryInfo len %d, min %zd, max 254\n",
 635                                              __func__,
 636                                              pcountryinfo->header.len,
 637                                              sizeof(pcountryinfo->countrycode));
 638                                 ret = -1;
 639                                 goto done;
 640                         }
 641
 642                         memcpy(&bss->countryinfo, pcountryinfo,
 643                                 pcountryinfo->header.len + 2);
 644                         lbs_deb_hex(LBS_DEB_SCAN, "process_bss: 11d countryinfo",
 645                                     (uint8_t *) pcountryinfo,
 646                                     (int) (pcountryinfo->header.len + 2));
 647                         break;
 648
 649                 case WLAN_EID_EXT_SUPP_RATES:
 650                         /* only process extended supported rate if data rate is
 651                          * already found. Data rate IE should come before
 652                          * extended supported rate IE
 653                          */
 654                         lbs_deb_scan("got RATESEX IE\n");
 655                         if (!got_basic_rates) {
 656                                 lbs_deb_scan("... but ignoring it\n");
 657                                 break;
 658                         }
 659
 660                         n_ex_rates = pos[1];
 661                         if (n_basic_rates + n_ex_rates > MAX_RATES)
 662                                 n_ex_rates = MAX_RATES - n_basic_rates;
 663
 664                         p = bss->rates + n_basic_rates;
 665                         memcpy(p, pos + 2, n_ex_rates);
 666                         break;
 667
 668                 case WLAN_EID_GENERIC:
 669                         if (pos[1] >= 4 &&
 670                             pos[2] == 0x00 && pos[3] == 0x50 &&
 671                             pos[4] == 0xf2 && pos[5] == 0x01) {
 672                                 bss->wpa_ie_len = min(pos[1] + 2, MAX_WPA_IE_LEN);
 673                                 memcpy(bss->wpa_ie, pos, bss->wpa_ie_len);
 674                                 lbs_deb_scan("got WPA IE\n");
 675                                 lbs_deb_hex(LBS_DEB_SCAN, "WPA IE", bss->wpa_ie,
 676                                             bss->wpa_ie_len);
 677                         } else if (pos[1] >= MARVELL_MESH_IE_LENGTH &&
 678                                    pos[2] == 0x00 && pos[3] == 0x50 &&
 679                                    pos[4] == 0x43 && pos[5] == 0x04) {
 680                                 lbs_deb_scan("got mesh IE\n");
 681                                 bss->mesh = 1;
 682                         } else {
 683                                 lbs_deb_scan("got generic IE: %02x:%02x:%02x:%02x, len %d\n",
 684                                         pos[2], pos[3],
 685                                         pos[4], pos[5],
 686                                         pos[1]);
 687                         }
 688                         break;
 689
 690                 case WLAN_EID_RSN:
 691                         lbs_deb_scan("got RSN IE\n");
 692                         bss->rsn_ie_len = min(pos[1] + 2, MAX_WPA_IE_LEN);
 693                         memcpy(bss->rsn_ie, pos, bss->rsn_ie_len);
 694                         lbs_deb_hex(LBS_DEB_SCAN, "process_bss: RSN_IE",
 695                                     bss->rsn_ie, bss->rsn_ie_len);
 696                         break;
 697
 698                 default:
 699                         lbs_deb_scan("got IE 0x%04x, len %d\n",
 700                                      pos[0], pos[1]);
 701                         break;
 702                 }
 703
 704                 pos += pos[1] + 2;
 705         }
 706
 707         /* Timestamp */
 708         bss->last_scanned = jiffies;
 709         lbs_unset_basic_rate_flags(bss->rates, sizeof(bss->rates));
 710
 711         ret = 0;
 712
 713 done:
 714         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
 715         return ret;
 716 }
 717
 718 /**
 719  *  @brief Send a scan command for all available channels filtered on a spec
 720  *
 721  *  Used in association code and from debugfs
 722  *
 723  *  @param priv             A pointer to struct lbs_private structure
 724  *  @param ssid             A pointer to the SSID to scan for
 725  *  @param ssid_len         Length of the SSID
 726  *
 727  *  @return                0-success, otherwise fail
 728  */
 729 int lbs_send_specific_ssid_scan(struct lbs_private *priv, uint8_t *ssid,
 730                                 uint8_t ssid_len)
 731 {
 732         DECLARE_SSID_BUF(ssid_buf);
 733         int ret = 0;
 734
 735         lbs_deb_enter_args(LBS_DEB_SCAN, "SSID '%s'\n",
 736                            print_ssid(ssid_buf, ssid, ssid_len));
 737
 738         if (!ssid_len)
 739                 goto out;
 740
 741         memcpy(priv->scan_ssid, ssid, ssid_len);
 742         priv->scan_ssid_len = ssid_len;
 743
 744         lbs_scan_networks(priv, 1);
 745         if (priv->surpriseremoved) {
 746                 ret = -1;
 747                 goto out;
 748         }
 749
 750 out:
 751         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
 752         return ret;
 753 }
 754
 755
 756
 757
 758 /*********************************************************************/
 759 /*                                                                   */
 760 /*  Support for Wireless Extensions                                  */
 761 /*                                                                   */
 762 /*********************************************************************/
 763
 764
 765 #define MAX_CUSTOM_LEN 64
 766
 767 static inline char *lbs_translate_scan(struct lbs_private *priv,
 768                                             struct iw_request_info *info,
 769                                             char *start, char *stop,
 770                                             struct bss_descriptor *bss)
 771 {
 772         struct chan_freq_power *cfp;
 773         char *current_val;      /* For rates */
 774         struct iw_event iwe;    /* Temporary buffer */
 775         int j;
 776 #define PERFECT_RSSI ((uint8_t)50)
 777 #define WORST_RSSI   ((uint8_t)0)
 778 #define RSSI_DIFF    ((uint8_t)(PERFECT_RSSI - WORST_RSSI))
 779         uint8_t rssi;
 780
 781         lbs_deb_enter(LBS_DEB_SCAN);
 782
 783         cfp = lbs_find_cfp_by_band_and_channel(priv, 0, bss->channel);
 784         if (!cfp) {
 785                 lbs_deb_scan("Invalid channel number %d\n", bss->channel);
 786                 start = NULL;
 787                 goto out;
 788         }
 789
 790         /* First entry *MUST* be the BSSID */
 791         iwe.cmd = SIOCGIWAP;
 792         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
 793         memcpy(iwe.u.ap_addr.sa_data, &bss->bssid, ETH_ALEN);
 794         start = iwe_stream_add_event(info, start, stop, &iwe, IW_EV_ADDR_LEN);
 795
 796         /* SSID */
 797         iwe.cmd = SIOCGIWESSID;
 798         iwe.u.data.flags = 1;
 799         iwe.u.data.length = min((uint32_t) bss->ssid_len, (uint32_t) IW_ESSID_MAX_SIZE);
 800         start = iwe_stream_add_point(info, start, stop, &iwe, bss->ssid);
 801
 802         /* Mode */
 803         iwe.cmd = SIOCGIWMODE;
 804         iwe.u.mode = bss->mode;
 805         start = iwe_stream_add_event(info, start, stop, &iwe, IW_EV_UINT_LEN);
 806
 807         /* Frequency */
 808         iwe.cmd = SIOCGIWFREQ;
 809         iwe.u.freq.m = (long)cfp->freq * 100000;
 810         iwe.u.freq.e = 1;
 811         start = iwe_stream_add_event(info, start, stop, &iwe, IW_EV_FREQ_LEN);
 812
 813         /* Add quality statistics */
 814         iwe.cmd = IWEVQUAL;
 815         iwe.u.qual.updated = IW_QUAL_ALL_UPDATED;
 816         iwe.u.qual.level = SCAN_RSSI(bss->rssi);
 817
 818         rssi = iwe.u.qual.level - MRVDRV_NF_DEFAULT_SCAN_VALUE;
 819         iwe.u.qual.qual =
 820                 (100 * RSSI_DIFF * RSSI_DIFF - (PERFECT_RSSI - rssi) *
 821                  (15 * (RSSI_DIFF) + 62 * (PERFECT_RSSI - rssi))) /
 822                 (RSSI_DIFF * RSSI_DIFF);
 823         if (iwe.u.qual.qual > 100)
 824                 iwe.u.qual.qual = 100;
 825
 826         if (priv->NF[TYPE_BEACON][TYPE_NOAVG] == 0) {
 827                 iwe.u.qual.noise = MRVDRV_NF_DEFAULT_SCAN_VALUE;
 828         } else {
 829                 iwe.u.qual.noise = CAL_NF(priv->NF[TYPE_BEACON][TYPE_NOAVG]);
 830         }
 831
 832         /* Locally created ad-hoc BSSs won't have beacons if this is the
 833          * only station in the adhoc network; so get signal strength
 834          * from receive statistics.
 835          */
 836         if ((priv->mode == IW_MODE_ADHOC) && priv->adhoccreate
 837             && !lbs_ssid_cmp(priv->curbssparams.ssid,
 838                              priv->curbssparams.ssid_len,
 839                              bss->ssid, bss->ssid_len)) {
 840                 int snr, nf;
 841                 snr = priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
 842                 nf = priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
 843                 iwe.u.qual.level = CAL_RSSI(snr, nf);
 844         }
 845         start = iwe_stream_add_event(info, start, stop, &iwe, IW_EV_QUAL_LEN);
 846
 847         /* Add encryption capability */
 848         iwe.cmd = SIOCGIWENCODE;
 849         if (bss->capability & WLAN_CAPABILITY_PRIVACY) {
 850                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
 851         } else {
 852                 iwe.u.data.flags = IW_ENCODE_DISABLED;
 853         }
 854         iwe.u.data.length = 0;
 855         start = iwe_stream_add_point(info, start, stop, &iwe, bss->ssid);
 856
 857         current_val = start + iwe_stream_lcp_len(info);
 858
 859         iwe.cmd = SIOCGIWRATE;
 860         iwe.u.bitrate.fixed = 0;
 861         iwe.u.bitrate.disabled = 0;
 862         iwe.u.bitrate.value = 0;
 863
 864         for (j = 0; j < ARRAY_SIZE(bss->rates) && bss->rates[j]; j++) {
 865                 /* Bit rate given in 500 kb/s units */
 866                 iwe.u.bitrate.value = bss->rates[j] * 500000;
 867                 current_val = iwe_stream_add_value(info, start, current_val,
 868                                                    stop, &iwe, IW_EV_PARAM_LEN);
 869         }
 870         if ((bss->mode == IW_MODE_ADHOC) && priv->adhoccreate
 871             && !lbs_ssid_cmp(priv->curbssparams.ssid,
 872                              priv->curbssparams.ssid_len,
 873                              bss->ssid, bss->ssid_len)) {
 874                 iwe.u.bitrate.value = 22 * 500000;
 875                 current_val = iwe_stream_add_value(info, start, current_val,
 876                                                    stop, &iwe, IW_EV_PARAM_LEN);
 877         }
 878         /* Check if we added any event */
 879         if ((current_val - start) > iwe_stream_lcp_len(info))
 880                 start = current_val;
 881
 882         memset(&iwe, 0, sizeof(iwe));
 883         if (bss->wpa_ie_len) {
 884                 char buf[MAX_WPA_IE_LEN];
 885                 memcpy(buf, bss->wpa_ie, bss->wpa_ie_len);
 886                 iwe.cmd = IWEVGENIE;
 887                 iwe.u.data.length = bss->wpa_ie_len;
 888                 start = iwe_stream_add_point(info, start, stop, &iwe, buf);
 889         }
 890
 891         memset(&iwe, 0, sizeof(iwe));
 892         if (bss->rsn_ie_len) {
 893                 char buf[MAX_WPA_IE_LEN];
 894                 memcpy(buf, bss->rsn_ie, bss->rsn_ie_len);
 895                 iwe.cmd = IWEVGENIE;
 896                 iwe.u.data.length = bss->rsn_ie_len;
 897                 start = iwe_stream_add_point(info, start, stop, &iwe, buf);
 898         }
 899
 900         if (bss->mesh) {
 901                 char custom[MAX_CUSTOM_LEN];
 902                 char *p = custom;
 903
 904                 iwe.cmd = IWEVCUSTOM;
 905                 p += snprintf(p, MAX_CUSTOM_LEN, "mesh-type: olpc");
 906                 iwe.u.data.length = p - custom;
 907                 if (iwe.u.data.length)
 908                         start = iwe_stream_add_point(info, start, stop,
 909                                                      &iwe, custom);
 910         }
 911
 912 out:
 913         lbs_deb_leave_args(LBS_DEB_SCAN, "start %p", start);
 914         return start;
 915 }
 916
 917
 918 /**
 919  *  @brief Handle Scan Network ioctl
 920  *
 921  *  @param dev          A pointer to net_device structure
 922  *  @param info         A pointer to iw_request_info structure
 923  *  @param vwrq         A pointer to iw_param structure
 924  *  @param extra        A pointer to extra data buf
 925  *
 926  *  @return             0 --success, otherwise fail
 927  */
 928 int lbs_set_scan(struct net_device *dev, struct iw_request_info *info,
 929                  union iwreq_data *wrqu, char *extra)
 930 {
 931         DECLARE_SSID_BUF(ssid);
 932         struct lbs_private *priv = dev->ml_priv;
 933         int ret = 0;
 934
 935         lbs_deb_enter(LBS_DEB_WEXT);
 936
 937         if (!priv->radio_on) {
 938                 ret = -EINVAL;
 939                 goto out;
 940         }
 941
 942         if (!netif_running(dev)) {
 943                 ret = -ENETDOWN;
 944                 goto out;
 945         }
 946
 947         /* mac80211 does this:
 948         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 949         if (sdata->type != IEEE80211_IF_TYPE_xxx) {
 950                 ret = -EOPNOTSUPP;
 951                 goto out;
 952         }
 953         */
 954
 955         if (wrqu->data.length == sizeof(struct iw_scan_req) &&
 956             wrqu->data.flags & IW_SCAN_THIS_ESSID) {
 957                 struct iw_scan_req *req = (struct iw_scan_req *)extra;
 958                 priv->scan_ssid_len = req->essid_len;
 959                 memcpy(priv->scan_ssid, req->essid, priv->scan_ssid_len);
 960                 lbs_deb_wext("set_scan, essid '%s'\n",
 961                         print_ssid(ssid, priv->scan_ssid, priv->scan_ssid_len));
 962         } else {
 963                 priv->scan_ssid_len = 0;
 964         }
 965
 966         if (!delayed_work_pending(&priv->scan_work))
 967                 queue_delayed_work(priv->work_thread, &priv->scan_work,
 968                                    msecs_to_jiffies(50));
 969         /* set marker that currently a scan is taking place */
 970         priv->scan_channel = -1;
 971
 972         if (priv->surpriseremoved)
 973                 ret = -EIO;
 974
 975 out:
 976         lbs_deb_leave_args(LBS_DEB_WEXT, "ret %d", ret);
 977         return ret;
 978 }
 979
 980
 981 /**
 982  *  @brief  Handle Retrieve scan table ioctl
 983  *
 984  *  @param dev          A pointer to net_device structure
 985  *  @param info         A pointer to iw_request_info structure
 986  *  @param dwrq         A pointer to iw_point structure
 987  *  @param extra        A pointer to extra data buf
 988  *
 989  *  @return             0 --success, otherwise fail
 990  */
 991 int lbs_get_scan(struct net_device *dev, struct iw_request_info *info,
 992                  struct iw_point *dwrq, char *extra)
 993 {
 994 #define SCAN_ITEM_SIZE 128
 995         struct lbs_private *priv = dev->ml_priv;
 996         int err = 0;
 997         char *ev = extra;
 998         char *stop = ev + dwrq->length;
 999         struct bss_descriptor *iter_bss;
1000         struct bss_descriptor *safe;
1001
1002         lbs_deb_enter(LBS_DEB_WEXT);
1003
1004         /* iwlist should wait until the current scan is finished */
1005         if (priv->scan_channel)
1006                 return -EAGAIN;
1007
1008         /* Update RSSI if current BSS is a locally created ad-hoc BSS */
1009         if ((priv->mode == IW_MODE_ADHOC) && priv->adhoccreate) {
1010                 err = lbs_prepare_and_send_command(priv, CMD_802_11_RSSI, 0,
1011                                 CMD_OPTION_WAITFORRSP, 0, NULL);
1012                 if (err)
1013                         goto out;
1014         }
1015
1016         mutex_lock(&priv->lock);
1017         list_for_each_entry_safe (iter_bss, safe, &priv->network_list, list) {
1018                 char *next_ev;
1019                 unsigned long stale_time;
1020
1021                 if (stop - ev < SCAN_ITEM_SIZE) {
1022                         err = -E2BIG;
1023                         break;
1024                 }
1025
1026                 /* For mesh device, list only mesh networks */
1027                 if (dev == priv->mesh_dev && !iter_bss->mesh)
1028                         continue;
1029
1030                 /* Prune old an old scan result */
1031                 stale_time = iter_bss->last_scanned + DEFAULT_MAX_SCAN_AGE;
1032                 if (time_after(jiffies, stale_time)) {
1033                         list_move_tail(&iter_bss->list, &priv->network_free_list);
1034                         clear_bss_descriptor(iter_bss);
1035                         continue;
1036                 }
1037
1038                 /* Translate to WE format this entry */
1039                 next_ev = lbs_translate_scan(priv, info, ev, stop, iter_bss);
1040                 if (next_ev == NULL)
1041                         continue;
1042                 ev = next_ev;
1043         }
1044         mutex_unlock(&priv->lock);
1045
1046         dwrq->length = (ev - extra);
1047         dwrq->flags = 0;
1048 out:
1049         lbs_deb_leave_args(LBS_DEB_WEXT, "ret %d", err);
1050         return err;
1051 }
1052
1053
1054
1055
1056 /*********************************************************************/
1057 /*                                                                   */
1058 /*  Command execution                                                */
1059 /*                                                                   */
1060 /*********************************************************************/
1061
1062
1063 /**
1064  *  @brief This function handles the command response of scan
1065  *
1066  *  Called from handle_cmd_response() in cmdrespc.
1067  *
1068  *   The response buffer for the scan command has the following
1069  *      memory layout:
1070  *
1071  *     .-----------------------------------------------------------.
1072  *     |  header (4 * sizeof(u16)):  Standard command response hdr |
1073  *     .-----------------------------------------------------------.
1074  *     |  bufsize (u16) : sizeof the BSS Description data          |
1075  *     .-----------------------------------------------------------.
1076  *     |  NumOfSet (u8) : Number of BSS Descs returned             |
1077  *     .-----------------------------------------------------------.
1078  *     |  BSSDescription data (variable, size given in bufsize)    |
1079  *     .-----------------------------------------------------------.
1080  *     |  TLV data (variable, size calculated using header->size,  |
1081  *     |            bufsize and sizeof the fixed fields above)     |
1082  *     .-----------------------------------------------------------.
1083  *
1084  *  @param priv    A pointer to struct lbs_private structure
1085  *  @param resp    A pointer to cmd_ds_command
1086  *
1087  *  @return        0 or -1
1088  */
1089 static int lbs_ret_80211_scan(struct lbs_private *priv, unsigned long dummy,
1090                               struct cmd_header *resp)
1091 {
1092         struct cmd_ds_802_11_scan_rsp *scanresp = (void *)resp;
1093         struct bss_descriptor *iter_bss;
1094         struct bss_descriptor *safe;
1095         uint8_t *bssinfo;
1096         uint16_t scanrespsize;
1097         int bytesleft;
1098         int idx;
1099         int tlvbufsize;
1100         int ret;
1101
1102         lbs_deb_enter(LBS_DEB_SCAN);
1103
1104         /* Prune old entries from scan table */
1105         list_for_each_entry_safe (iter_bss, safe, &priv->network_list, list) {
1106                 unsigned long stale_time = iter_bss->last_scanned + DEFAULT_MAX_SCAN_AGE;
1107                 if (time_before(jiffies, stale_time))
1108                         continue;
1109                 list_move_tail (&iter_bss->list, &priv->network_free_list);
1110                 clear_bss_descriptor(iter_bss);
1111         }
1112
1113         if (scanresp->nr_sets > MAX_NETWORK_COUNT) {
1114                 lbs_deb_scan("SCAN_RESP: too many scan results (%d, max %d)\n",
1115                              scanresp->nr_sets, MAX_NETWORK_COUNT);
1116                 ret = -1;
1117                 goto done;
1118         }
1119
1120         bytesleft = get_unaligned_le16(&scanresp->bssdescriptsize);
1121         lbs_deb_scan("SCAN_RESP: bssdescriptsize %d\n", bytesleft);
1122
1123         scanrespsize = le16_to_cpu(resp->size);
1124         lbs_deb_scan("SCAN_RESP: scan results %d\n", scanresp->nr_sets);
1125
1126         bssinfo = scanresp->bssdesc_and_tlvbuffer;
1127
1128         /* The size of the TLV buffer is equal to the entire command response
1129          *   size (scanrespsize) minus the fixed fields (sizeof()'s), the
1130          *   BSS Descriptions (bssdescriptsize as bytesLef) and the command
1131          *   response header (S_DS_GEN)
1132          */
1133         tlvbufsize = scanrespsize - (bytesleft + sizeof(scanresp->bssdescriptsize)
1134                                      + sizeof(scanresp->nr_sets)
1135                                      + S_DS_GEN);
1136
1137         /*
1138          *  Process each scan response returned (scanresp->nr_sets). Save
1139          *    the information in the newbssentry and then insert into the
1140          *    driver scan table either as an update to an existing entry
1141          *    or as an addition at the end of the table
1142          */
1143         for (idx = 0; idx < scanresp->nr_sets && bytesleft; idx++) {
1144                 struct bss_descriptor new;
1145                 struct bss_descriptor *found = NULL;
1146                 struct bss_descriptor *oldest = NULL;
1147
1148                 /* Process the data fields and IEs returned for this BSS */
1149                 memset(&new, 0, sizeof (struct bss_descriptor));
1150                 if (lbs_process_bss(&new, &bssinfo, &bytesleft) != 0) {
1151                         /* error parsing the scan response, skipped */
1152                         lbs_deb_scan("SCAN_RESP: process_bss returned ERROR\n");
1153                         continue;
1154                 }
1155
1156                 /* Try to find this bss in the scan table */
1157                 list_for_each_entry (iter_bss, &priv->network_list, list) {
1158                         if (is_same_network(iter_bss, &new)) {
1159                                 found = iter_bss;
1160                                 break;
1161                         }
1162
1163                         if ((oldest == NULL) ||
1164                             (iter_bss->last_scanned < oldest->last_scanned))
1165                                 oldest = iter_bss;
1166                 }
1167
1168                 if (found) {
1169                         /* found, clear it */
1170                         clear_bss_descriptor(found);
1171                 } else if (!list_empty(&priv->network_free_list)) {
1172                         /* Pull one from the free list */
1173                         found = list_entry(priv->network_free_list.next,
1174                                            struct bss_descriptor, list);
1175                         list_move_tail(&found->list, &priv->network_list);
1176                 } else if (oldest) {
1177                         /* If there are no more slots, expire the oldest */
1178                         found = oldest;
1179                         clear_bss_descriptor(found);
1180                         list_move_tail(&found->list, &priv->network_list);
1181                 } else {
1182                         continue;
1183                 }
1184
1185                 lbs_deb_scan("SCAN_RESP: BSSID %pM\n", new.bssid);
1186
1187                 /* Copy the locally created newbssentry to the scan table */
1188                 memcpy(found, &new, offsetof(struct bss_descriptor, list));
1189         }
1190
1191         ret = 0;
1192
1193 done:
1194         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
1195         return ret;
1196 }