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/ctype.h>
   8 #include <linux/if.h>
   9 #include <linux/netdevice.h>
  10 #include <linux/wireless.h>
  11 #include <linux/etherdevice.h>
  12
  13 #include <net/ieee80211.h>
  14 #include <net/iw_handler.h>
  15
  16 #include "host.h"
  17 #include "decl.h"
  18 #include "dev.h"
  19 #include "scan.h"
  20 #include "join.h"
  21
  22 //! Approximate amount of data needed to pass a scan result back to iwlist
  23 #define MAX_SCAN_CELL_SIZE  (IW_EV_ADDR_LEN             \
  24                              + IW_ESSID_MAX_SIZE        \
  25                              + IW_EV_UINT_LEN           \
  26                              + IW_EV_FREQ_LEN           \
  27                              + IW_EV_QUAL_LEN           \
  28                              + IW_ESSID_MAX_SIZE        \
  29                              + IW_EV_PARAM_LEN          \
  30                              + 40)      /* 40 for WPAIE */
  31
  32 //! Memory needed to store a max sized channel List TLV for a firmware scan
  33 #define CHAN_TLV_MAX_SIZE  (sizeof(struct mrvlietypesheader)    \
  34                             + (MRVDRV_MAX_CHANNELS_PER_SCAN     \
  35                                * sizeof(struct chanscanparamset)))
  36
  37 //! Memory needed to store a max number/size SSID TLV for a firmware scan
  38 #define SSID_TLV_MAX_SIZE  (1 * sizeof(struct mrvlietypes_ssidparamset))
  39
  40 //! Maximum memory needed for a wlan_scan_cmd_config with all TLVs at max
  41 #define MAX_SCAN_CFG_ALLOC (sizeof(struct wlan_scan_cmd_config)  \
  42                             + sizeof(struct mrvlietypes_numprobes)   \
  43                             + CHAN_TLV_MAX_SIZE                 \
  44                             + SSID_TLV_MAX_SIZE)
  45
  46 //! The maximum number of channels the firmware can scan per command
  47 #define MRVDRV_MAX_CHANNELS_PER_SCAN   14
  48
  49 /**
  50  * @brief Number of channels to scan per firmware scan command issuance.
  51  *
  52  *  Number restricted to prevent hitting the limit on the amount of scan data
  53  *  returned in a single firmware scan command.
  54  */
  55 #define MRVDRV_CHANNELS_PER_SCAN_CMD   4
  56
  57 //! Scan time specified in the channel TLV for each channel for passive scans
  58 #define MRVDRV_PASSIVE_SCAN_CHAN_TIME  100
  59
  60 //! Scan time specified in the channel TLV for each channel for active scans
  61 #define MRVDRV_ACTIVE_SCAN_CHAN_TIME   100
  62
  63 static const u8 zeromac[ETH_ALEN] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
  64 static const u8 bcastmac[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
  65
  66 static inline void clear_bss_descriptor (struct bss_descriptor * bss)
  67 {
  68         /* Don't blow away ->list, just BSS data */
  69         memset(bss, 0, offsetof(struct bss_descriptor, list));
  70 }
  71
  72 static inline int match_bss_no_security(struct wlan_802_11_security * secinfo,
  73                         struct bss_descriptor * match_bss)
  74 {
  75         if (   !secinfo->wep_enabled
  76             && !secinfo->WPAenabled
  77             && !secinfo->WPA2enabled
  78             && match_bss->wpa_ie[0] != MFIE_TYPE_GENERIC
  79             && match_bss->rsn_ie[0] != MFIE_TYPE_RSN
  80             && !(match_bss->capability & WLAN_CAPABILITY_PRIVACY)) {
  81                 return 1;
  82         }
  83         return 0;
  84 }
  85
  86 static inline int match_bss_static_wep(struct wlan_802_11_security * secinfo,
  87                         struct bss_descriptor * match_bss)
  88 {
  89         if ( secinfo->wep_enabled
  90            && !secinfo->WPAenabled
  91            && !secinfo->WPA2enabled
  92            && (match_bss->capability & WLAN_CAPABILITY_PRIVACY)) {
  93                 return 1;
  94         }
  95         return 0;
  96 }
  97
  98 static inline int match_bss_wpa(struct wlan_802_11_security * secinfo,
  99                         struct bss_descriptor * match_bss)
 100 {
 101         if (  !secinfo->wep_enabled
 102            && secinfo->WPAenabled
 103            && (match_bss->wpa_ie[0] == MFIE_TYPE_GENERIC)
 104            /* privacy bit may NOT be set in some APs like LinkSys WRT54G
 105               && (match_bss->capability & WLAN_CAPABILITY_PRIVACY)) {
 106             */
 107            ) {
 108                 return 1;
 109         }
 110         return 0;
 111 }
 112
 113 static inline int match_bss_wpa2(struct wlan_802_11_security * secinfo,
 114                         struct bss_descriptor * match_bss)
 115 {
 116         if (  !secinfo->wep_enabled
 117            && secinfo->WPA2enabled
 118            && (match_bss->rsn_ie[0] == MFIE_TYPE_RSN)
 119            /* privacy bit may NOT be set in some APs like LinkSys WRT54G
 120               && (match_bss->capability & WLAN_CAPABILITY_PRIVACY)) {
 121             */
 122            ) {
 123                 return 1;
 124         }
 125         return 0;
 126 }
 127
 128 static inline int match_bss_dynamic_wep(struct wlan_802_11_security * secinfo,
 129                         struct bss_descriptor * match_bss)
 130 {
 131         if (  !secinfo->wep_enabled
 132            && !secinfo->WPAenabled
 133            && !secinfo->WPA2enabled
 134            && (match_bss->wpa_ie[0] != MFIE_TYPE_GENERIC)
 135            && (match_bss->rsn_ie[0] != MFIE_TYPE_RSN)
 136            && (match_bss->capability & WLAN_CAPABILITY_PRIVACY)) {
 137                 return 1;
 138         }
 139         return 0;
 140 }
 141
 142 /**
 143  *  @brief Check if a scanned network compatible with the driver settings
 144  *
 145  *   WEP     WPA     WPA2    ad-hoc  encrypt                      Network
 146  * enabled enabled  enabled   AES     mode   privacy  WPA  WPA2  Compatible
 147  *    0       0        0       0      NONE      0      0    0   yes No security
 148  *    1       0        0       0      NONE      1      0    0   yes Static WEP
 149  *    0       1        0       0       x        1x     1    x   yes WPA
 150  *    0       0        1       0       x        1x     x    1   yes WPA2
 151  *    0       0        0       1      NONE      1      0    0   yes Ad-hoc AES
 152  *    0       0        0       0     !=NONE     1      0    0   yes Dynamic WEP
 153  *
 154  *
 155  *  @param adapter A pointer to wlan_adapter
 156  *  @param index   Index in scantable to check against current driver settings
 157  *  @param mode    Network mode: Infrastructure or IBSS
 158  *
 159  *  @return        Index in scantable, or error code if negative
 160  */
 161 static int is_network_compatible(wlan_adapter * adapter,
 162                 struct bss_descriptor * bss, u8 mode)
 163 {
 164         int matched = 0;
 165
 166         lbs_deb_enter(LBS_DEB_ASSOC);
 167
 168         if (bss->mode != mode)
 169                 goto done;
 170
 171         if ((matched = match_bss_no_security(&adapter->secinfo, bss))) {
 172                 goto done;
 173         } else if ((matched = match_bss_static_wep(&adapter->secinfo, bss))) {
 174                 goto done;
 175         } else if ((matched = match_bss_wpa(&adapter->secinfo, bss))) {
 176                 lbs_deb_scan(
 177                        "is_network_compatible() WPA: wpa_ie=%#x "
 178                        "wpa2_ie=%#x WEP=%s WPA=%s WPA2=%s "
 179                        "privacy=%#x\n", bss->wpa_ie[0], bss->rsn_ie[0],
 180                        adapter->secinfo.wep_enabled ? "e" : "d",
 181                        adapter->secinfo.WPAenabled ? "e" : "d",
 182                        adapter->secinfo.WPA2enabled ? "e" : "d",
 183                        (bss->capability & WLAN_CAPABILITY_PRIVACY));
 184                 goto done;
 185         } else if ((matched = match_bss_wpa2(&adapter->secinfo, bss))) {
 186                 lbs_deb_scan(
 187                        "is_network_compatible() WPA2: wpa_ie=%#x "
 188                        "wpa2_ie=%#x WEP=%s WPA=%s WPA2=%s "
 189                        "privacy=%#x\n", bss->wpa_ie[0], bss->rsn_ie[0],
 190                        adapter->secinfo.wep_enabled ? "e" : "d",
 191                        adapter->secinfo.WPAenabled ? "e" : "d",
 192                        adapter->secinfo.WPA2enabled ? "e" : "d",
 193                        (bss->capability & WLAN_CAPABILITY_PRIVACY));
 194                 goto done;
 195         } else if ((matched = match_bss_dynamic_wep(&adapter->secinfo, bss))) {
 196                 lbs_deb_scan(
 197                        "is_network_compatible() dynamic WEP: "
 198                        "wpa_ie=%#x wpa2_ie=%#x privacy=%#x\n",
 199                        bss->wpa_ie[0], bss->rsn_ie[0],
 200                        (bss->capability & WLAN_CAPABILITY_PRIVACY));
 201                 goto done;
 202         }
 203
 204         /* bss security settings don't match those configured on card */
 205         lbs_deb_scan(
 206                "is_network_compatible() FAILED: wpa_ie=%#x "
 207                "wpa2_ie=%#x WEP=%s WPA=%s WPA2=%s privacy=%#x\n",
 208                bss->wpa_ie[0], bss->rsn_ie[0],
 209                adapter->secinfo.wep_enabled ? "e" : "d",
 210                adapter->secinfo.WPAenabled ? "e" : "d",
 211                adapter->secinfo.WPA2enabled ? "e" : "d",
 212                (bss->capability & WLAN_CAPABILITY_PRIVACY));
 213
 214 done:
 215         lbs_deb_leave(LBS_DEB_SCAN);
 216         return matched;
 217 }
 218
 219 /**
 220  *  @brief Create a channel list for the driver to scan based on region info
 221  *
 222  *  Use the driver region/band information to construct a comprehensive list
 223  *    of channels to scan.  This routine is used for any scan that is not
 224  *    provided a specific channel list to scan.
 225  *
 226  *  @param priv          A pointer to wlan_private structure
 227  *  @param scanchanlist  Output parameter: resulting channel list to scan
 228  *  @param filteredscan  Flag indicating whether or not a BSSID or SSID filter
 229  *                       is being sent in the command to firmware.  Used to
 230  *                       increase the number of channels sent in a scan
 231  *                       command and to disable the firmware channel scan
 232  *                       filter.
 233  *
 234  *  @return              void
 235  */
 236 static void wlan_scan_create_channel_list(wlan_private * priv,
 237                                           struct chanscanparamset * scanchanlist,
 238                                           u8 filteredscan)
 239 {
 240
 241         wlan_adapter *adapter = priv->adapter;
 242         struct region_channel *scanregion;
 243         struct chan_freq_power *cfp;
 244         int rgnidx;
 245         int chanidx;
 246         int nextchan;
 247         u8 scantype;
 248
 249         chanidx = 0;
 250
 251         /* Set the default scan type to the user specified type, will later
 252          *   be changed to passive on a per channel basis if restricted by
 253          *   regulatory requirements (11d or 11h)
 254          */
 255         scantype = CMD_SCAN_TYPE_ACTIVE;
 256
 257         for (rgnidx = 0; rgnidx < ARRAY_SIZE(adapter->region_channel); rgnidx++) {
 258                 if (priv->adapter->enable11d &&
 259                     adapter->connect_status != LIBERTAS_CONNECTED) {
 260                         /* Scan all the supported chan for the first scan */
 261                         if (!adapter->universal_channel[rgnidx].valid)
 262                                 continue;
 263                         scanregion = &adapter->universal_channel[rgnidx];
 264
 265                         /* clear the parsed_region_chan for the first scan */
 266                         memset(&adapter->parsed_region_chan, 0x00,
 267                                sizeof(adapter->parsed_region_chan));
 268                 } else {
 269                         if (!adapter->region_channel[rgnidx].valid)
 270                                 continue;
 271                         scanregion = &adapter->region_channel[rgnidx];
 272                 }
 273
 274                 for (nextchan = 0;
 275                      nextchan < scanregion->nrcfp; nextchan++, chanidx++) {
 276
 277                         cfp = scanregion->CFP + nextchan;
 278
 279                         if (priv->adapter->enable11d) {
 280                                 scantype =
 281                                     libertas_get_scan_type_11d(cfp->channel,
 282                                                            &adapter->
 283                                                            parsed_region_chan);
 284                         }
 285
 286                         switch (scanregion->band) {
 287                         case BAND_B:
 288                         case BAND_G:
 289                         default:
 290                                 scanchanlist[chanidx].radiotype =
 291                                     CMD_SCAN_RADIO_TYPE_BG;
 292                                 break;
 293                         }
 294
 295                         if (scantype == CMD_SCAN_TYPE_PASSIVE) {
 296                                 scanchanlist[chanidx].maxscantime =
 297                                     cpu_to_le16(MRVDRV_PASSIVE_SCAN_CHAN_TIME);
 298                                 scanchanlist[chanidx].chanscanmode.passivescan =
 299                                     1;
 300                         } else {
 301                                 scanchanlist[chanidx].maxscantime =
 302                                     cpu_to_le16(MRVDRV_ACTIVE_SCAN_CHAN_TIME);
 303                                 scanchanlist[chanidx].chanscanmode.passivescan =
 304                                     0;
 305                         }
 306
 307                         scanchanlist[chanidx].channumber = cfp->channel;
 308
 309                         if (filteredscan) {
 310                                 scanchanlist[chanidx].chanscanmode.
 311                                     disablechanfilt = 1;
 312                         }
 313                 }
 314         }
 315 }
 316
 317 /**
 318  *  @brief Construct a wlan_scan_cmd_config structure to use in issue scan cmds
 319  *
 320  *  Application layer or other functions can invoke wlan_scan_networks
 321  *    with a scan configuration supplied in a wlan_ioctl_user_scan_cfg struct.
 322  *    This structure is used as the basis of one or many wlan_scan_cmd_config
 323  *    commands that are sent to the command processing module and sent to
 324  *    firmware.
 325  *
 326  *  Create a wlan_scan_cmd_config based on the following user supplied
 327  *    parameters (if present):
 328  *             - SSID filter
 329  *             - BSSID filter
 330  *             - Number of Probes to be sent
 331  *             - channel list
 332  *
 333  *  If the SSID or BSSID filter is not present, disable/clear the filter.
 334  *  If the number of probes is not set, use the adapter default setting
 335  *  Qualify the channel
 336  *
 337  *  @param priv             A pointer to wlan_private structure
 338  *  @param puserscanin      NULL or pointer to scan configuration parameters
 339  *  @param ppchantlvout     Output parameter: Pointer to the start of the
 340  *                          channel TLV portion of the output scan config
 341  *  @param pscanchanlist    Output parameter: Pointer to the resulting channel
 342  *                          list to scan
 343  *  @param pmaxchanperscan  Output parameter: Number of channels to scan for
 344  *                          each issuance of the firmware scan command
 345  *  @param pfilteredscan    Output parameter: Flag indicating whether or not
 346  *                          a BSSID or SSID filter is being sent in the
 347  *                          command to firmware.  Used to increase the number
 348  *                          of channels sent in a scan command and to
 349  *                          disable the firmware channel scan filter.
 350  *  @param pscancurrentonly Output parameter: Flag indicating whether or not
 351  *                          we are only scanning our current active channel
 352  *
 353  *  @return                 resulting scan configuration
 354  */
 355 static struct wlan_scan_cmd_config *
 356 wlan_scan_setup_scan_config(wlan_private * priv,
 357                             const struct wlan_ioctl_user_scan_cfg * puserscanin,
 358                             struct mrvlietypes_chanlistparamset ** ppchantlvout,
 359                             struct chanscanparamset * pscanchanlist,
 360                             int *pmaxchanperscan,
 361                             u8 * pfilteredscan,
 362                             u8 * pscancurrentonly)
 363 {
 364         struct mrvlietypes_numprobes *pnumprobestlv;
 365         struct mrvlietypes_ssidparamset *pssidtlv;
 366         struct wlan_scan_cmd_config * pscancfgout = NULL;
 367         u8 *ptlvpos;
 368         u16 numprobes;
 369         int chanidx;
 370         int scantype;
 371         int scandur;
 372         int channel;
 373         int radiotype;
 374
 375         pscancfgout = kzalloc(MAX_SCAN_CFG_ALLOC, GFP_KERNEL);
 376         if (pscancfgout == NULL)
 377                 goto out;
 378
 379         /* The tlvbufferlen is calculated for each scan command.  The TLVs added
 380          *   in this routine will be preserved since the routine that sends
 381          *   the command will append channelTLVs at *ppchantlvout.  The difference
 382          *   between the *ppchantlvout and the tlvbuffer start will be used
 383          *   to calculate the size of anything we add in this routine.
 384          */
 385         pscancfgout->tlvbufferlen = 0;
 386
 387         /* Running tlv pointer.  Assigned to ppchantlvout at end of function
 388          *  so later routines know where channels can be added to the command buf
 389          */
 390         ptlvpos = pscancfgout->tlvbuffer;
 391
 392         /*
 393          * Set the initial scan paramters for progressive scanning.  If a specific
 394          *   BSSID or SSID is used, the number of channels in the scan command
 395          *   will be increased to the absolute maximum
 396          */
 397         *pmaxchanperscan = MRVDRV_CHANNELS_PER_SCAN_CMD;
 398
 399         /* Initialize the scan as un-filtered by firmware, set to TRUE below if
 400          *   a SSID or BSSID filter is sent in the command
 401          */
 402         *pfilteredscan = 0;
 403
 404         /* Initialize the scan as not being only on the current channel.  If
 405          *   the channel list is customized, only contains one channel, and
 406          *   is the active channel, this is set true and data flow is not halted.
 407          */
 408         *pscancurrentonly = 0;
 409
 410         if (puserscanin) {
 411
 412                 /* Set the bss type scan filter, use adapter setting if unset */
 413                 pscancfgout->bsstype =
 414                     puserscanin->bsstype ? puserscanin->bsstype : CMD_BSS_TYPE_ANY;
 415
 416                 /* Set the number of probes to send, use adapter setting if unset */
 417                 numprobes = puserscanin->numprobes ? puserscanin->numprobes : 0;
 418
 419                 /*
 420                  * Set the BSSID filter to the incoming configuration,
 421                  *   if non-zero.  If not set, it will remain disabled (all zeros).
 422                  */
 423                 memcpy(pscancfgout->bssid, puserscanin->bssid,
 424                        sizeof(pscancfgout->bssid));
 425
 426                 if (puserscanin->ssid_len) {
 427                         pssidtlv =
 428                             (struct mrvlietypes_ssidparamset *) pscancfgout->
 429                             tlvbuffer;
 430                         pssidtlv->header.type = cpu_to_le16(TLV_TYPE_SSID);
 431                         pssidtlv->header.len = cpu_to_le16(puserscanin->ssid_len);
 432                         memcpy(pssidtlv->ssid, puserscanin->ssid,
 433                                puserscanin->ssid_len);
 434                         ptlvpos += sizeof(pssidtlv->header) + puserscanin->ssid_len;
 435                 }
 436
 437                 /*
 438                  *  The default number of channels sent in the command is low to
 439                  *    ensure the response buffer from the firmware does not truncate
 440                  *    scan results.  That is not an issue with an SSID or BSSID
 441                  *    filter applied to the scan results in the firmware.
 442                  */
 443                 if (   puserscanin->ssid_len
 444                     || (compare_ether_addr(pscancfgout->bssid, &zeromac[0]) != 0)) {
 445                         *pmaxchanperscan = MRVDRV_MAX_CHANNELS_PER_SCAN;
 446                         *pfilteredscan = 1;
 447                 }
 448         } else {
 449                 pscancfgout->bsstype = CMD_BSS_TYPE_ANY;
 450                 numprobes = 0;
 451         }
 452
 453         /* If the input config or adapter has the number of Probes set, add tlv */
 454         if (numprobes) {
 455                 pnumprobestlv = (struct mrvlietypes_numprobes *) ptlvpos;
 456                 pnumprobestlv->header.type = cpu_to_le16(TLV_TYPE_NUMPROBES);
 457                 pnumprobestlv->header.len = cpu_to_le16(2);
 458                 pnumprobestlv->numprobes = cpu_to_le16(numprobes);
 459
 460                 ptlvpos += sizeof(*pnumprobestlv);
 461         }
 462
 463         /*
 464          * Set the output for the channel TLV to the address in the tlv buffer
 465          *   past any TLVs that were added in this fuction (SSID, numprobes).
 466          *   channel TLVs will be added past this for each scan command, preserving
 467          *   the TLVs that were previously added.
 468          */
 469         *ppchantlvout = (struct mrvlietypes_chanlistparamset *) ptlvpos;
 470
 471         if (puserscanin && puserscanin->chanlist[0].channumber) {
 472
 473                 lbs_deb_scan("Scan: Using supplied channel list\n");
 474
 475                 for (chanidx = 0;
 476                      chanidx < WLAN_IOCTL_USER_SCAN_CHAN_MAX
 477                      && puserscanin->chanlist[chanidx].channumber; chanidx++) {
 478
 479                         channel = puserscanin->chanlist[chanidx].channumber;
 480                         (pscanchanlist + chanidx)->channumber = channel;
 481
 482                         radiotype = puserscanin->chanlist[chanidx].radiotype;
 483                         (pscanchanlist + chanidx)->radiotype = radiotype;
 484
 485                         scantype = puserscanin->chanlist[chanidx].scantype;
 486
 487                         if (scantype == CMD_SCAN_TYPE_PASSIVE) {
 488                                 (pscanchanlist +
 489                                  chanidx)->chanscanmode.passivescan = 1;
 490                         } else {
 491                                 (pscanchanlist +
 492                                  chanidx)->chanscanmode.passivescan = 0;
 493                         }
 494
 495                         if (puserscanin->chanlist[chanidx].scantime) {
 496                                 scandur =
 497                                     puserscanin->chanlist[chanidx].scantime;
 498                         } else {
 499                                 if (scantype == CMD_SCAN_TYPE_PASSIVE) {
 500                                         scandur = MRVDRV_PASSIVE_SCAN_CHAN_TIME;
 501                                 } else {
 502                                         scandur = MRVDRV_ACTIVE_SCAN_CHAN_TIME;
 503                                 }
 504                         }
 505
 506                         (pscanchanlist + chanidx)->minscantime =
 507                             cpu_to_le16(scandur);
 508                         (pscanchanlist + chanidx)->maxscantime =
 509                             cpu_to_le16(scandur);
 510                 }
 511
 512                 /* Check if we are only scanning the current channel */
 513                 if ((chanidx == 1) && (puserscanin->chanlist[0].channumber
 514                                        ==
 515                                        priv->adapter->curbssparams.channel)) {
 516                         *pscancurrentonly = 1;
 517                         lbs_deb_scan("Scan: Scanning current channel only");
 518                 }
 519
 520         } else {
 521                 lbs_deb_scan("Scan: Creating full region channel list\n");
 522                 wlan_scan_create_channel_list(priv, pscanchanlist,
 523                                               *pfilteredscan);
 524         }
 525
 526 out:
 527         return pscancfgout;
 528 }
 529
 530 /**
 531  *  @brief Construct and send multiple scan config commands to the firmware
 532  *
 533  *  Previous routines have created a wlan_scan_cmd_config with any requested
 534  *   TLVs.  This function splits the channel TLV into maxchanperscan lists
 535  *   and sends the portion of the channel TLV along with the other TLVs
 536  *   to the wlan_cmd routines for execution in the firmware.
 537  *
 538  *  @param priv            A pointer to wlan_private structure
 539  *  @param maxchanperscan  Maximum number channels to be included in each
 540  *                         scan command sent to firmware
 541  *  @param filteredscan    Flag indicating whether or not a BSSID or SSID
 542  *                         filter is being used for the firmware command
 543  *                         scan command sent to firmware
 544  *  @param pscancfgout     Scan configuration used for this scan.
 545  *  @param pchantlvout     Pointer in the pscancfgout where the channel TLV
 546  *                         should start.  This is past any other TLVs that
 547  *                         must be sent down in each firmware command.
 548  *  @param pscanchanlist   List of channels to scan in maxchanperscan segments
 549  *
 550  *  @return                0 or error return otherwise
 551  */
 552 static int wlan_scan_channel_list(wlan_private * priv,
 553                                   int maxchanperscan,
 554                                   u8 filteredscan,
 555                                   struct wlan_scan_cmd_config * pscancfgout,
 556                                   struct mrvlietypes_chanlistparamset * pchantlvout,
 557                                   struct chanscanparamset * pscanchanlist,
 558                                   const struct wlan_ioctl_user_scan_cfg * puserscanin,
 559                                   int full_scan)
 560 {
 561         struct chanscanparamset *ptmpchan;
 562         struct chanscanparamset *pstartchan;
 563         u8 scanband;
 564         int doneearly;
 565         int tlvidx;
 566         int ret = 0;
 567         int scanned = 0;
 568         union iwreq_data wrqu;
 569
 570         lbs_deb_enter(LBS_DEB_ASSOC);
 571
 572         if (pscancfgout == 0 || pchantlvout == 0 || pscanchanlist == 0) {
 573                 lbs_deb_scan("Scan: Null detect: %p, %p, %p\n",
 574                        pscancfgout, pchantlvout, pscanchanlist);
 575                 return -1;
 576         }
 577
 578         pchantlvout->header.type = cpu_to_le16(TLV_TYPE_CHANLIST);
 579
 580         /* Set the temp channel struct pointer to the start of the desired list */
 581         ptmpchan = pscanchanlist;
 582
 583         if (priv->adapter->last_scanned_channel && !puserscanin)
 584                 ptmpchan += priv->adapter->last_scanned_channel;
 585
 586         /* Loop through the desired channel list, sending a new firmware scan
 587          *   commands for each maxchanperscan channels (or for 1,6,11 individually
 588          *   if configured accordingly)
 589          */
 590         while (ptmpchan->channumber) {
 591
 592                 tlvidx = 0;
 593                 pchantlvout->header.len = 0;
 594                 scanband = ptmpchan->radiotype;
 595                 pstartchan = ptmpchan;
 596                 doneearly = 0;
 597
 598                 /* Construct the channel TLV for the scan command.  Continue to
 599                  *  insert channel TLVs until:
 600                  *    - the tlvidx hits the maximum configured per scan command
 601                  *    - the next channel to insert is 0 (end of desired channel list)
 602                  *    - doneearly is set (controlling individual scanning of 1,6,11)
 603                  */
 604                 while (tlvidx < maxchanperscan && ptmpchan->channumber
 605                        && !doneearly && scanned < 2) {
 606
 607             lbs_deb_scan(
 608                     "Scan: Chan(%3d), Radio(%d), mode(%d,%d), Dur(%d)\n",
 609                 ptmpchan->channumber, ptmpchan->radiotype,
 610                 ptmpchan->chanscanmode.passivescan,
 611                 ptmpchan->chanscanmode.disablechanfilt,
 612                 ptmpchan->maxscantime);
 613
 614                         /* Copy the current channel TLV to the command being prepared */
 615                         memcpy(pchantlvout->chanscanparam + tlvidx,
 616                                ptmpchan, sizeof(pchantlvout->chanscanparam));
 617
 618                         /* Increment the TLV header length by the size appended */
 619                         /* Ew, it would be _so_ nice if we could just declare the
 620                            variable little-endian and let GCC handle it for us */
 621                         pchantlvout->header.len =
 622                                 cpu_to_le16(le16_to_cpu(pchantlvout->header.len) +
 623                                             sizeof(pchantlvout->chanscanparam));
 624
 625                         /*
 626                          *  The tlv buffer length is set to the number of bytes of the
 627                          *    between the channel tlv pointer and the start of the
 628                          *    tlv buffer.  This compensates for any TLVs that were appended
 629                          *    before the channel list.
 630                          */
 631                         pscancfgout->tlvbufferlen = ((u8 *) pchantlvout
 632                                                      - pscancfgout->tlvbuffer);
 633
 634                         /*  Add the size of the channel tlv header and the data length */
 635                         pscancfgout->tlvbufferlen +=
 636                             (sizeof(pchantlvout->header)
 637                              + le16_to_cpu(pchantlvout->header.len));
 638
 639                         /* Increment the index to the channel tlv we are constructing */
 640                         tlvidx++;
 641
 642                         doneearly = 0;
 643
 644                         /* Stop the loop if the *current* channel is in the 1,6,11 set
 645                          *   and we are not filtering on a BSSID or SSID.
 646                          */
 647                         if (!filteredscan && (ptmpchan->channumber == 1
 648                                               || ptmpchan->channumber == 6
 649                                               || ptmpchan->channumber == 11)) {
 650                                 doneearly = 1;
 651                         }
 652
 653                         /* Increment the tmp pointer to the next channel to be scanned */
 654                         ptmpchan++;
 655                         scanned++;
 656
 657                         /* Stop the loop if the *next* channel is in the 1,6,11 set.
 658                          *  This will cause it to be the only channel scanned on the next
 659                          *  interation
 660                          */
 661                         if (!filteredscan && (ptmpchan->channumber == 1
 662                                               || ptmpchan->channumber == 6
 663                                               || ptmpchan->channumber == 11)) {
 664                                 doneearly = 1;
 665                         }
 666                 }
 667
 668                 /* Send the scan command to the firmware with the specified cfg */
 669                 ret = libertas_prepare_and_send_command(priv, CMD_802_11_SCAN, 0,
 670                                             0, 0, pscancfgout);
 671                 if (scanned >= 2 && !full_scan) {
 672                         ret = 0;
 673                         goto done;
 674                 }
 675                 scanned = 0;
 676         }
 677
 678 done:
 679         priv->adapter->last_scanned_channel = ptmpchan->channumber;
 680
 681         /* Tell userspace the scan table has been updated */
 682         memset(&wrqu, 0, sizeof(union iwreq_data));
 683         wireless_send_event(priv->dev, SIOCGIWSCAN, &wrqu, NULL);
 684
 685         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
 686         return ret;
 687 }
 688
 689 static void
 690 clear_selected_scan_list_entries(wlan_adapter * adapter,
 691                                  const struct wlan_ioctl_user_scan_cfg * scan_cfg)
 692 {
 693         struct bss_descriptor * bss;
 694         struct bss_descriptor * safe;
 695         u32 clear_ssid_flag = 0, clear_bssid_flag = 0;
 696
 697         if (!scan_cfg)
 698                 return;
 699
 700         if (scan_cfg->clear_ssid && scan_cfg->ssid_len)
 701                 clear_ssid_flag = 1;
 702
 703         if (scan_cfg->clear_bssid
 704             && (compare_ether_addr(scan_cfg->bssid, &zeromac[0]) != 0)
 705             && (compare_ether_addr(scan_cfg->bssid, &bcastmac[0]) != 0)) {
 706                 clear_bssid_flag = 1;
 707         }
 708
 709         if (!clear_ssid_flag && !clear_bssid_flag)
 710                 return;
 711
 712         mutex_lock(&adapter->lock);
 713         list_for_each_entry_safe (bss, safe, &adapter->network_list, list) {
 714                 u32 clear = 0;
 715
 716                 /* Check for an SSID match */
 717                 if (   clear_ssid_flag
 718                     && (bss->ssid_len == scan_cfg->ssid_len)
 719                     && !memcmp(bss->ssid, scan_cfg->ssid, bss->ssid_len))
 720                         clear = 1;
 721
 722                 /* Check for a BSSID match */
 723                 if (   clear_bssid_flag
 724                     && !compare_ether_addr(bss->bssid, scan_cfg->bssid))
 725                         clear = 1;
 726
 727                 if (clear) {
 728                         list_move_tail (&bss->list, &adapter->network_free_list);
 729                         clear_bss_descriptor(bss);
 730                 }
 731         }
 732         mutex_unlock(&adapter->lock);
 733 }
 734
 735
 736 /**
 737  *  @brief Internal function used to start a scan based on an input config
 738  *
 739  *  Use the input user scan configuration information when provided in
 740  *    order to send the appropriate scan commands to firmware to populate or
 741  *    update the internal driver scan table
 742  *
 743  *  @param priv          A pointer to wlan_private structure
 744  *  @param puserscanin   Pointer to the input configuration for the requested
 745  *                       scan.
 746  *
 747  *  @return              0 or < 0 if error
 748  */
 749 int wlan_scan_networks(wlan_private * priv,
 750                               const struct wlan_ioctl_user_scan_cfg * puserscanin,
 751                               int full_scan)
 752 {
 753         wlan_adapter * adapter = priv->adapter;
 754         struct mrvlietypes_chanlistparamset *pchantlvout;
 755         struct chanscanparamset * scan_chan_list = NULL;
 756         struct wlan_scan_cmd_config * scan_cfg = NULL;
 757         u8 filteredscan;
 758         u8 scancurrentchanonly;
 759         int maxchanperscan;
 760         int ret;
 761 #ifdef CONFIG_LIBERTAS_DEBUG
 762         struct bss_descriptor * iter_bss;
 763         int i = 0;
 764 #endif
 765
 766         lbs_deb_enter(LBS_DEB_ASSOC);
 767
 768         scan_chan_list = kzalloc(sizeof(struct chanscanparamset) *
 769                                 WLAN_IOCTL_USER_SCAN_CHAN_MAX, GFP_KERNEL);
 770         if (scan_chan_list == NULL) {
 771                 ret = -ENOMEM;
 772                 goto out;
 773         }
 774
 775         scan_cfg = wlan_scan_setup_scan_config(priv,
 776                                                puserscanin,
 777                                                &pchantlvout,
 778                                                scan_chan_list,
 779                                                &maxchanperscan,
 780                                                &filteredscan,
 781                                                &scancurrentchanonly);
 782         if (scan_cfg == NULL) {
 783                 ret = -ENOMEM;
 784                 goto out;
 785         }
 786
 787         clear_selected_scan_list_entries(adapter, puserscanin);
 788
 789         /* Keep the data path active if we are only scanning our current channel */
 790         if (!scancurrentchanonly) {
 791                 netif_stop_queue(priv->dev);
 792                 netif_carrier_off(priv->dev);
 793                 if (priv->mesh_dev) {
 794                         netif_stop_queue(priv->mesh_dev);
 795                         netif_carrier_off(priv->mesh_dev);
 796                 }
 797         }
 798
 799         ret = wlan_scan_channel_list(priv,
 800                                      maxchanperscan,
 801                                      filteredscan,
 802                                      scan_cfg,
 803                                      pchantlvout,
 804                                      scan_chan_list,
 805                                      puserscanin,
 806                                      full_scan);
 807
 808 #ifdef CONFIG_LIBERTAS_DEBUG
 809         /* Dump the scan table */
 810         mutex_lock(&adapter->lock);
 811         list_for_each_entry (iter_bss, &adapter->network_list, list) {
 812                 lbs_deb_scan("Scan:(%02d) " MAC_FMT ", RSSI[%03d], SSID[%s]\n",
 813                        i++, MAC_ARG(iter_bss->bssid), (s32) iter_bss->rssi,
 814                        escape_essid(iter_bss->ssid, iter_bss->ssid_len));
 815         }
 816         mutex_unlock(&adapter->lock);
 817 #endif
 818
 819         if (priv->adapter->connect_status == LIBERTAS_CONNECTED) {
 820                 netif_carrier_on(priv->dev);
 821                 netif_wake_queue(priv->dev);
 822                 if (priv->mesh_dev) {
 823                         netif_carrier_on(priv->mesh_dev);
 824                         netif_wake_queue(priv->mesh_dev);
 825                 }
 826         }
 827
 828 out:
 829         if (scan_cfg)
 830                 kfree(scan_cfg);
 831
 832         if (scan_chan_list)
 833                 kfree(scan_chan_list);
 834
 835         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
 836         return ret;
 837 }
 838
 839 /**
 840  *  @brief Interpret a BSS scan response returned from the firmware
 841  *
 842  *  Parse the various fixed fields and IEs passed back for a a BSS probe
 843  *   response or beacon from the scan command.  Record information as needed
 844  *   in the scan table struct bss_descriptor for that entry.
 845  *
 846  *  @param bss  Output parameter: Pointer to the BSS Entry
 847  *
 848  *  @return             0 or -1
 849  */
 850 static int libertas_process_bss(struct bss_descriptor * bss,
 851                                 u8 ** pbeaconinfo, int *bytesleft)
 852 {
 853         struct ieeetypes_fhparamset *pFH;
 854         struct ieeetypes_dsparamset *pDS;
 855         struct ieeetypes_cfparamset *pCF;
 856         struct ieeetypes_ibssparamset *pibss;
 857         struct ieeetypes_countryinfoset *pcountryinfo;
 858         u8 *pos, *end, *p;
 859         u8 n_ex_rates = 0, got_basic_rates = 0, n_basic_rates = 0;
 860         u16 beaconsize = 0;
 861         int ret;
 862
 863         lbs_deb_enter(LBS_DEB_ASSOC);
 864
 865         if (*bytesleft >= sizeof(beaconsize)) {
 866                 /* Extract & convert beacon size from the command buffer */
 867                 beaconsize = le16_to_cpup((void *)*pbeaconinfo);
 868                 *bytesleft -= sizeof(beaconsize);
 869                 *pbeaconinfo += sizeof(beaconsize);
 870         }
 871
 872         if (beaconsize == 0 || beaconsize > *bytesleft) {
 873                 *pbeaconinfo += *bytesleft;
 874                 *bytesleft = 0;
 875                 return -1;
 876         }
 877
 878         /* Initialize the current working beacon pointer for this BSS iteration */
 879         pos = *pbeaconinfo;
 880         end = pos + beaconsize;
 881
 882         /* Advance the return beacon pointer past the current beacon */
 883         *pbeaconinfo += beaconsize;
 884         *bytesleft -= beaconsize;
 885
 886         memcpy(bss->bssid, pos, ETH_ALEN);
 887         lbs_deb_scan("process_bss: AP BSSID " MAC_FMT "\n", MAC_ARG(bss->bssid));
 888         pos += ETH_ALEN;
 889
 890         if ((end - pos) < 12) {
 891                 lbs_deb_scan("process_bss: Not enough bytes left\n");
 892                 return -1;
 893         }
 894
 895         /*
 896          * next 4 fields are RSSI, time stamp, beacon interval,
 897          *   and capability information
 898          */
 899
 900         /* RSSI is 1 byte long */
 901         bss->rssi = *pos;
 902         lbs_deb_scan("process_bss: RSSI=%02X\n", *pos);
 903         pos++;
 904
 905         /* time stamp is 8 bytes long */
 906         pos += 8;
 907
 908         /* beacon interval is 2 bytes long */
 909         bss->beaconperiod = le16_to_cpup((void *) pos);
 910         pos += 2;
 911
 912         /* capability information is 2 bytes long */
 913         bss->capability = le16_to_cpup((void *) pos);
 914         lbs_deb_scan("process_bss: capabilities = 0x%4X\n", bss->capability);
 915         pos += 2;
 916
 917         if (bss->capability & WLAN_CAPABILITY_PRIVACY)
 918                 lbs_deb_scan("process_bss: AP WEP enabled\n");
 919         if (bss->capability & WLAN_CAPABILITY_IBSS)
 920                 bss->mode = IW_MODE_ADHOC;
 921         else
 922                 bss->mode = IW_MODE_INFRA;
 923
 924         /* rest of the current buffer are IE's */
 925         lbs_deb_scan("process_bss: IE length for this AP = %zd\n", end - pos);
 926         lbs_deb_hex(LBS_DEB_SCAN, "process_bss: IE info", pos, end - pos);
 927
 928         /* process variable IE */
 929         while (pos <= end - 2) {
 930                 struct ieee80211_info_element * elem =
 931                         (struct ieee80211_info_element *) pos;
 932
 933                 if (pos + elem->len > end) {
 934                         lbs_deb_scan("process_bss: error in processing IE, "
 935                                "bytes left < IE length\n");
 936                         break;
 937                 }
 938
 939                 switch (elem->id) {
 940                 case MFIE_TYPE_SSID:
 941                         bss->ssid_len = elem->len;
 942                         memcpy(bss->ssid, elem->data, elem->len);
 943                         lbs_deb_scan("ssid '%s', ssid length %u\n",
 944                                      escape_essid(bss->ssid, bss->ssid_len),
 945                                      bss->ssid_len);
 946                         break;
 947
 948                 case MFIE_TYPE_RATES:
 949                         n_basic_rates = min_t(u8, MAX_RATES, elem->len);
 950                         memcpy(bss->rates, elem->data, n_basic_rates);
 951                         got_basic_rates = 1;
 952                         break;
 953
 954                 case MFIE_TYPE_FH_SET:
 955                         pFH = (struct ieeetypes_fhparamset *) pos;
 956                         memmove(&bss->phyparamset.fhparamset, pFH,
 957                                 sizeof(struct ieeetypes_fhparamset));
 958 #if 0 /* I think we can store these LE */
 959                         bss->phyparamset.fhparamset.dwelltime
 960                             = le16_to_cpu(bss->phyparamset.fhparamset.dwelltime);
 961 #endif
 962                         break;
 963
 964                 case MFIE_TYPE_DS_SET:
 965                         pDS = (struct ieeetypes_dsparamset *) pos;
 966                         bss->channel = pDS->currentchan;
 967                         memcpy(&bss->phyparamset.dsparamset, pDS,
 968                                sizeof(struct ieeetypes_dsparamset));
 969                         break;
 970
 971                 case MFIE_TYPE_CF_SET:
 972                         pCF = (struct ieeetypes_cfparamset *) pos;
 973                         memcpy(&bss->ssparamset.cfparamset, pCF,
 974                                sizeof(struct ieeetypes_cfparamset));
 975                         break;
 976
 977                 case MFIE_TYPE_IBSS_SET:
 978                         pibss = (struct ieeetypes_ibssparamset *) pos;
 979                         bss->atimwindow = le32_to_cpu(pibss->atimwindow);
 980                         memmove(&bss->ssparamset.ibssparamset, pibss,
 981                                 sizeof(struct ieeetypes_ibssparamset));
 982 #if 0
 983                         bss->ssparamset.ibssparamset.atimwindow
 984                             = le16_to_cpu(bss->ssparamset.ibssparamset.atimwindow);
 985 #endif
 986                         break;
 987
 988                 case MFIE_TYPE_COUNTRY:
 989                         pcountryinfo = (struct ieeetypes_countryinfoset *) pos;
 990                         if (pcountryinfo->len < sizeof(pcountryinfo->countrycode)
 991                             || pcountryinfo->len > 254) {
 992                                 lbs_deb_scan("process_bss: 11D- Err "
 993                                        "CountryInfo len =%d min=%zd max=254\n",
 994                                        pcountryinfo->len,
 995                                        sizeof(pcountryinfo->countrycode));
 996                                 ret = -1;
 997                                 goto done;
 998                         }
 999
1000                         memcpy(&bss->countryinfo,
1001                                pcountryinfo, pcountryinfo->len + 2);
1002                         lbs_deb_hex(LBS_DEB_SCAN, "process_bss: 11d countryinfo",
1003                                 (u8 *) pcountryinfo,
1004                                 (u32) (pcountryinfo->len + 2));
1005                         break;
1006
1007                 case MFIE_TYPE_RATES_EX:
1008                         /* only process extended supported rate if data rate is
1009                          * already found. Data rate IE should come before
1010                          * extended supported rate IE
1011                          */
1012                         if (!got_basic_rates)
1013                                 break;
1014
1015                         n_ex_rates = elem->len;
1016                         if (n_basic_rates + n_ex_rates > MAX_RATES)
1017                                 n_ex_rates = MAX_RATES - n_basic_rates;
1018
1019                         p = bss->rates + n_basic_rates;
1020                         memcpy(p, elem->data, n_ex_rates);
1021                         break;
1022
1023                 case MFIE_TYPE_GENERIC:
1024                         if (elem->len >= 4 &&
1025                             elem->data[0] == 0x00 &&
1026                             elem->data[1] == 0x50 &&
1027                             elem->data[2] == 0xf2 &&
1028                             elem->data[3] == 0x01) {
1029                                 bss->wpa_ie_len = min(elem->len + 2,
1030                                                       MAX_WPA_IE_LEN);
1031                                 memcpy(bss->wpa_ie, elem, bss->wpa_ie_len);
1032                                 lbs_deb_hex(LBS_DEB_SCAN, "process_bss: WPA IE", bss->wpa_ie,
1033                                             elem->len);
1034                         } else if (elem->len >= MARVELL_MESH_IE_LENGTH &&
1035                             elem->data[0] == 0x00 &&
1036                             elem->data[1] == 0x50 &&
1037                             elem->data[2] == 0x43 &&
1038                             elem->data[3] == 0x04) {
1039                                 bss->mesh = 1;
1040                         }
1041                         break;
1042
1043                 case MFIE_TYPE_RSN:
1044                         bss->rsn_ie_len = min(elem->len + 2, MAX_WPA_IE_LEN);
1045                         memcpy(bss->rsn_ie, elem, bss->rsn_ie_len);
1046                         lbs_deb_hex(LBS_DEB_SCAN, "process_bss: RSN_IE", bss->rsn_ie, elem->len);
1047                         break;
1048
1049                 default:
1050                         break;
1051                 }
1052
1053                 pos += elem->len + 2;
1054         }
1055
1056         /* Timestamp */
1057         bss->last_scanned = jiffies;
1058         libertas_unset_basic_rate_flags(bss->rates, sizeof(bss->rates));
1059
1060         ret = 0;
1061
1062 done:
1063         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
1064         return ret;
1065 }
1066
1067 /**
1068  *  @brief Compare two SSIDs
1069  *
1070  *  @param ssid1    A pointer to ssid to compare
1071  *  @param ssid2    A pointer to ssid to compare
1072  *
1073  *  @return         0--ssid is same, otherwise is different
1074  */
1075 int libertas_ssid_cmp(u8 *ssid1, u8 ssid1_len, u8 *ssid2, u8 ssid2_len)
1076 {
1077         if (ssid1_len != ssid2_len)
1078                 return -1;
1079
1080         return memcmp(ssid1, ssid2, ssid1_len);
1081 }
1082
1083 /**
1084  *  @brief This function finds a specific compatible BSSID in the scan list
1085  *
1086  *  @param adapter  A pointer to wlan_adapter
1087  *  @param bssid    BSSID to find in the scan list
1088  *  @param mode     Network mode: Infrastructure or IBSS
1089  *
1090  *  @return         index in BSSID list, or error return code (< 0)
1091  */
1092 struct bss_descriptor * libertas_find_bssid_in_list(wlan_adapter * adapter,
1093                 u8 * bssid, u8 mode)
1094 {
1095         struct bss_descriptor * iter_bss;
1096         struct bss_descriptor * found_bss = NULL;
1097
1098         if (!bssid)
1099                 return NULL;
1100
1101         lbs_deb_hex(LBS_DEB_SCAN, "looking for",
1102                 bssid, ETH_ALEN);
1103
1104         /* Look through the scan table for a compatible match.  The loop will
1105          *   continue past a matched bssid that is not compatible in case there
1106          *   is an AP with multiple SSIDs assigned to the same BSSID
1107          */
1108         mutex_lock(&adapter->lock);
1109         list_for_each_entry (iter_bss, &adapter->network_list, list) {
1110                 if (compare_ether_addr(iter_bss->bssid, bssid))
1111                         continue; /* bssid doesn't match */
1112                 switch (mode) {
1113                 case IW_MODE_INFRA:
1114                 case IW_MODE_ADHOC:
1115                         if (!is_network_compatible(adapter, iter_bss, mode))
1116                                 break;
1117                         found_bss = iter_bss;
1118                         break;
1119                 default:
1120                         found_bss = iter_bss;
1121                         break;
1122                 }
1123         }
1124         mutex_unlock(&adapter->lock);
1125
1126         return found_bss;
1127 }
1128
1129 /**
1130  *  @brief This function finds ssid in ssid list.
1131  *
1132  *  @param adapter  A pointer to wlan_adapter
1133  *  @param ssid     SSID to find in the list
1134  *  @param bssid    BSSID to qualify the SSID selection (if provided)
1135  *  @param mode     Network mode: Infrastructure or IBSS
1136  *
1137  *  @return         index in BSSID list
1138  */
1139 struct bss_descriptor * libertas_find_ssid_in_list(wlan_adapter * adapter,
1140                    u8 *ssid, u8 ssid_len, u8 * bssid, u8 mode,
1141                    int channel)
1142 {
1143         u8 bestrssi = 0;
1144         struct bss_descriptor * iter_bss = NULL;
1145         struct bss_descriptor * found_bss = NULL;
1146         struct bss_descriptor * tmp_oldest = NULL;
1147
1148         mutex_lock(&adapter->lock);
1149
1150         list_for_each_entry (iter_bss, &adapter->network_list, list) {
1151                 if (   !tmp_oldest
1152                     || (iter_bss->last_scanned < tmp_oldest->last_scanned))
1153                         tmp_oldest = iter_bss;
1154
1155                 if (libertas_ssid_cmp(iter_bss->ssid, iter_bss->ssid_len,
1156                                       ssid, ssid_len) != 0)
1157                         continue; /* ssid doesn't match */
1158                 if (bssid && compare_ether_addr(iter_bss->bssid, bssid) != 0)
1159                         continue; /* bssid doesn't match */
1160                 if ((channel > 0) && (iter_bss->channel != channel))
1161                         continue; /* channel doesn't match */
1162
1163                 switch (mode) {
1164                 case IW_MODE_INFRA:
1165                 case IW_MODE_ADHOC:
1166                         if (!is_network_compatible(adapter, iter_bss, mode))
1167                                 break;
1168
1169                         if (bssid) {
1170                                 /* Found requested BSSID */
1171                                 found_bss = iter_bss;
1172                                 goto out;
1173                         }
1174
1175                         if (SCAN_RSSI(iter_bss->rssi) > bestrssi) {
1176                                 bestrssi = SCAN_RSSI(iter_bss->rssi);
1177                                 found_bss = iter_bss;
1178                         }
1179                         break;
1180                 case IW_MODE_AUTO:
1181                 default:
1182                         if (SCAN_RSSI(iter_bss->rssi) > bestrssi) {
1183                                 bestrssi = SCAN_RSSI(iter_bss->rssi);
1184                                 found_bss = iter_bss;
1185                         }
1186                         break;
1187                 }
1188         }
1189
1190 out:
1191         mutex_unlock(&adapter->lock);
1192         return found_bss;
1193 }
1194
1195 /**
1196  *  @brief This function finds the best SSID in the Scan List
1197  *
1198  *  Search the scan table for the best SSID that also matches the current
1199  *   adapter network preference (infrastructure or adhoc)
1200  *
1201  *  @param adapter  A pointer to wlan_adapter
1202  *
1203  *  @return         index in BSSID list
1204  */
1205 static struct bss_descriptor * libertas_find_best_ssid_in_list(wlan_adapter * adapter,
1206                 u8 mode)
1207 {
1208         u8 bestrssi = 0;
1209         struct bss_descriptor * iter_bss;
1210         struct bss_descriptor * best_bss = NULL;
1211
1212         mutex_lock(&adapter->lock);
1213
1214         list_for_each_entry (iter_bss, &adapter->network_list, list) {
1215                 switch (mode) {
1216                 case IW_MODE_INFRA:
1217                 case IW_MODE_ADHOC:
1218                         if (!is_network_compatible(adapter, iter_bss, mode))
1219                                 break;
1220                         if (SCAN_RSSI(iter_bss->rssi) <= bestrssi)
1221                                 break;
1222                         bestrssi = SCAN_RSSI(iter_bss->rssi);
1223                         best_bss = iter_bss;
1224                         break;
1225                 case IW_MODE_AUTO:
1226                 default:
1227                         if (SCAN_RSSI(iter_bss->rssi) <= bestrssi)
1228                                 break;
1229                         bestrssi = SCAN_RSSI(iter_bss->rssi);
1230                         best_bss = iter_bss;
1231                         break;
1232                 }
1233         }
1234
1235         mutex_unlock(&adapter->lock);
1236         return best_bss;
1237 }
1238
1239 /**
1240  *  @brief Find the AP with specific ssid in the scan list
1241  *
1242  *  @param priv         A pointer to wlan_private structure
1243  *  @param pSSID        A pointer to AP's ssid
1244  *
1245  *  @return             0--success, otherwise--fail
1246  */
1247 int libertas_find_best_network_ssid(wlan_private * priv,
1248                 u8 *out_ssid, u8 *out_ssid_len, u8 preferred_mode, u8 *out_mode)
1249 {
1250         wlan_adapter *adapter = priv->adapter;
1251         int ret = -1;
1252         struct bss_descriptor * found;
1253
1254         lbs_deb_enter(LBS_DEB_ASSOC);
1255
1256         wlan_scan_networks(priv, NULL, 1);
1257         if (adapter->surpriseremoved)
1258                 return -1;
1259
1260         wait_event_interruptible(adapter->cmd_pending, !adapter->nr_cmd_pending);
1261
1262         found = libertas_find_best_ssid_in_list(adapter, preferred_mode);
1263         if (found && (found->ssid_len > 0)) {
1264                 memcpy(out_ssid, &found->ssid, IW_ESSID_MAX_SIZE);
1265                 *out_ssid_len = found->ssid_len;
1266                 *out_mode = found->mode;
1267                 ret = 0;
1268         }
1269
1270         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
1271         return ret;
1272 }
1273
1274 /**
1275  *  @brief Scan Network
1276  *
1277  *  @param dev          A pointer to net_device structure
1278  *  @param info         A pointer to iw_request_info structure
1279  *  @param vwrq         A pointer to iw_param structure
1280  *  @param extra        A pointer to extra data buf
1281  *
1282  *  @return             0 --success, otherwise fail
1283  */
1284 int libertas_set_scan(struct net_device *dev, struct iw_request_info *info,
1285                   struct iw_param *vwrq, char *extra)
1286 {
1287         wlan_private *priv = dev->priv;
1288         wlan_adapter *adapter = priv->adapter;
1289
1290         lbs_deb_enter(LBS_DEB_SCAN);
1291
1292         wlan_scan_networks(priv, NULL, 0);
1293
1294         if (adapter->surpriseremoved)
1295                 return -1;
1296
1297         lbs_deb_leave(LBS_DEB_SCAN);
1298         return 0;
1299 }
1300
1301 /**
1302  *  @brief Send a scan command for all available channels filtered on a spec
1303  *
1304  *  @param priv             A pointer to wlan_private structure
1305  *  @param prequestedssid   A pointer to AP's ssid
1306  *  @param keeppreviousscan Flag used to save/clear scan table before scan
1307  *
1308  *  @return                0-success, otherwise fail
1309  */
1310 int libertas_send_specific_ssid_scan(wlan_private * priv,
1311                         u8 *ssid, u8 ssid_len, u8 clear_ssid)
1312 {
1313         wlan_adapter *adapter = priv->adapter;
1314         struct wlan_ioctl_user_scan_cfg scancfg;
1315         int ret = 0;
1316
1317         lbs_deb_enter(LBS_DEB_ASSOC);
1318
1319         if (!ssid_len)
1320                 goto out;
1321
1322         memset(&scancfg, 0x00, sizeof(scancfg));
1323         memcpy(scancfg.ssid, ssid, ssid_len);
1324         scancfg.ssid_len = ssid_len;
1325         scancfg.clear_ssid = clear_ssid;
1326
1327         wlan_scan_networks(priv, &scancfg, 1);
1328         if (adapter->surpriseremoved)
1329                 return -1;
1330         wait_event_interruptible(adapter->cmd_pending, !adapter->nr_cmd_pending);
1331
1332 out:
1333         lbs_deb_leave(LBS_DEB_ASSOC);
1334         return ret;
1335 }
1336
1337 static inline char *libertas_translate_scan(wlan_private *priv,
1338                                         char *start, char *stop,
1339                                         struct bss_descriptor *bss)
1340 {
1341         wlan_adapter *adapter = priv->adapter;
1342         struct chan_freq_power *cfp;
1343         char *current_val;      /* For rates */
1344         struct iw_event iwe;    /* Temporary buffer */
1345         int j;
1346 #define PERFECT_RSSI ((u8)50)
1347 #define WORST_RSSI   ((u8)0)
1348 #define RSSI_DIFF    ((u8)(PERFECT_RSSI - WORST_RSSI))
1349         u8 rssi;
1350
1351         cfp = libertas_find_cfp_by_band_and_channel(adapter, 0, bss->channel);
1352         if (!cfp) {
1353                 lbs_deb_scan("Invalid channel number %d\n", bss->channel);
1354                 return NULL;
1355         }
1356
1357         /* First entry *MUST* be the AP BSSID */
1358         iwe.cmd = SIOCGIWAP;
1359         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1360         memcpy(iwe.u.ap_addr.sa_data, &bss->bssid, ETH_ALEN);
1361         start = iwe_stream_add_event(start, stop, &iwe, IW_EV_ADDR_LEN);
1362
1363         /* SSID */
1364         iwe.cmd = SIOCGIWESSID;
1365         iwe.u.data.flags = 1;
1366         iwe.u.data.length = min((u32) bss->ssid_len, (u32) IW_ESSID_MAX_SIZE);
1367         start = iwe_stream_add_point(start, stop, &iwe, bss->ssid);
1368
1369         /* Mode */
1370         iwe.cmd = SIOCGIWMODE;
1371         iwe.u.mode = bss->mode;
1372         start = iwe_stream_add_event(start, stop, &iwe, IW_EV_UINT_LEN);
1373
1374         /* Frequency */
1375         iwe.cmd = SIOCGIWFREQ;
1376         iwe.u.freq.m = (long)cfp->freq * 100000;
1377         iwe.u.freq.e = 1;
1378         start = iwe_stream_add_event(start, stop, &iwe, IW_EV_FREQ_LEN);
1379
1380         /* Add quality statistics */
1381         iwe.cmd = IWEVQUAL;
1382         iwe.u.qual.updated = IW_QUAL_ALL_UPDATED;
1383         iwe.u.qual.level = SCAN_RSSI(bss->rssi);
1384
1385         rssi = iwe.u.qual.level - MRVDRV_NF_DEFAULT_SCAN_VALUE;
1386         iwe.u.qual.qual =
1387             (100 * RSSI_DIFF * RSSI_DIFF - (PERFECT_RSSI - rssi) *
1388              (15 * (RSSI_DIFF) + 62 * (PERFECT_RSSI - rssi))) /
1389             (RSSI_DIFF * RSSI_DIFF);
1390         if (iwe.u.qual.qual > 100)
1391                 iwe.u.qual.qual = 100;
1392
1393         if (adapter->NF[TYPE_BEACON][TYPE_NOAVG] == 0) {
1394                 iwe.u.qual.noise = MRVDRV_NF_DEFAULT_SCAN_VALUE;
1395         } else {
1396                 iwe.u.qual.noise =
1397                     CAL_NF(adapter->NF[TYPE_BEACON][TYPE_NOAVG]);
1398         }
1399
1400         /* Locally created ad-hoc BSSs won't have beacons if this is the
1401          * only station in the adhoc network; so get signal strength
1402          * from receive statistics.
1403          */
1404         if ((adapter->mode == IW_MODE_ADHOC)
1405             && adapter->adhoccreate
1406             && !libertas_ssid_cmp(adapter->curbssparams.ssid,
1407                                   adapter->curbssparams.ssid_len,
1408                                   bss->ssid, bss->ssid_len)) {
1409                 int snr, nf;
1410                 snr = adapter->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
1411                 nf = adapter->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
1412                 iwe.u.qual.level = CAL_RSSI(snr, nf);
1413         }
1414         start = iwe_stream_add_event(start, stop, &iwe, IW_EV_QUAL_LEN);
1415
1416         /* Add encryption capability */
1417         iwe.cmd = SIOCGIWENCODE;
1418         if (bss->capability & WLAN_CAPABILITY_PRIVACY) {
1419                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1420         } else {
1421                 iwe.u.data.flags = IW_ENCODE_DISABLED;
1422         }
1423         iwe.u.data.length = 0;
1424         start = iwe_stream_add_point(start, stop, &iwe, bss->ssid);
1425
1426         current_val = start + IW_EV_LCP_LEN;
1427
1428         iwe.cmd = SIOCGIWRATE;
1429         iwe.u.bitrate.fixed = 0;
1430         iwe.u.bitrate.disabled = 0;
1431         iwe.u.bitrate.value = 0;
1432
1433         for (j = 0; bss->rates[j] && (j < sizeof(bss->rates)); j++) {
1434                 /* Bit rate given in 500 kb/s units */
1435                 iwe.u.bitrate.value = bss->rates[j] * 500000;
1436                 current_val = iwe_stream_add_value(start, current_val,
1437                                          stop, &iwe, IW_EV_PARAM_LEN);
1438         }
1439         if ((bss->mode == IW_MODE_ADHOC)
1440             && !libertas_ssid_cmp(adapter->curbssparams.ssid,
1441                                   adapter->curbssparams.ssid_len,
1442                                   bss->ssid, bss->ssid_len)
1443             && adapter->adhoccreate) {
1444                 iwe.u.bitrate.value = 22 * 500000;
1445                 current_val = iwe_stream_add_value(start, current_val,
1446                                          stop, &iwe, IW_EV_PARAM_LEN);
1447         }
1448         /* Check if we added any event */
1449         if((current_val - start) > IW_EV_LCP_LEN)
1450                 start = current_val;
1451
1452         memset(&iwe, 0, sizeof(iwe));
1453         if (bss->wpa_ie_len) {
1454                 char buf[MAX_WPA_IE_LEN];
1455                 memcpy(buf, bss->wpa_ie, bss->wpa_ie_len);
1456                 iwe.cmd = IWEVGENIE;
1457                 iwe.u.data.length = bss->wpa_ie_len;
1458                 start = iwe_stream_add_point(start, stop, &iwe, buf);
1459         }
1460
1461         memset(&iwe, 0, sizeof(iwe));
1462         if (bss->rsn_ie_len) {
1463                 char buf[MAX_WPA_IE_LEN];
1464                 memcpy(buf, bss->rsn_ie, bss->rsn_ie_len);
1465                 iwe.cmd = IWEVGENIE;
1466                 iwe.u.data.length = bss->rsn_ie_len;
1467                 start = iwe_stream_add_point(start, stop, &iwe, buf);
1468         }
1469
1470         return start;
1471 }
1472
1473 /**
1474  *  @brief  Retrieve the scan table entries via wireless tools IOCTL call
1475  *
1476  *  @param dev          A pointer to net_device structure
1477  *  @param info         A pointer to iw_request_info structure
1478  *  @param dwrq         A pointer to iw_point structure
1479  *  @param extra        A pointer to extra data buf
1480  *
1481  *  @return             0 --success, otherwise fail
1482  */
1483 int libertas_get_scan(struct net_device *dev, struct iw_request_info *info,
1484                   struct iw_point *dwrq, char *extra)
1485 {
1486 #define SCAN_ITEM_SIZE 128
1487         wlan_private *priv = dev->priv;
1488         wlan_adapter *adapter = priv->adapter;
1489         int err = 0;
1490         char *ev = extra;
1491         char *stop = ev + dwrq->length;
1492         struct bss_descriptor * iter_bss;
1493         struct bss_descriptor * safe;
1494
1495         lbs_deb_enter(LBS_DEB_ASSOC);
1496
1497         /* If we've got an uncompleted scan, schedule the next part */
1498         if (!adapter->nr_cmd_pending && adapter->last_scanned_channel)
1499                 wlan_scan_networks(priv, NULL, 0);
1500
1501         /* Update RSSI if current BSS is a locally created ad-hoc BSS */
1502         if ((adapter->mode == IW_MODE_ADHOC) && adapter->adhoccreate) {
1503                 libertas_prepare_and_send_command(priv, CMD_802_11_RSSI, 0,
1504                                         CMD_OPTION_WAITFORRSP, 0, NULL);
1505         }
1506
1507         mutex_lock(&adapter->lock);
1508         list_for_each_entry_safe (iter_bss, safe, &adapter->network_list, list) {
1509                 char * next_ev;
1510                 unsigned long stale_time;
1511
1512                 if (stop - ev < SCAN_ITEM_SIZE) {
1513                         err = -E2BIG;
1514                         break;
1515                 }
1516
1517                 /* For mesh device, list only mesh networks */
1518                 if (dev == priv->mesh_dev && !iter_bss->mesh)
1519                         continue;
1520
1521                 /* Prune old an old scan result */
1522                 stale_time = iter_bss->last_scanned + DEFAULT_MAX_SCAN_AGE;
1523                 if (time_after(jiffies, stale_time)) {
1524                         list_move_tail (&iter_bss->list,
1525                                         &adapter->network_free_list);
1526                         clear_bss_descriptor(iter_bss);
1527                         continue;
1528                 }
1529
1530                 /* Translate to WE format this entry */
1531                 next_ev = libertas_translate_scan(priv, ev, stop, iter_bss);
1532                 if (next_ev == NULL)
1533                         continue;
1534                 ev = next_ev;
1535         }
1536         mutex_unlock(&adapter->lock);
1537
1538         dwrq->length = (ev - extra);
1539         dwrq->flags = 0;
1540
1541         lbs_deb_leave(LBS_DEB_ASSOC);
1542         return err;
1543 }
1544
1545 /**
1546  *  @brief Prepare a scan command to be sent to the firmware
1547  *
1548  *  Use the wlan_scan_cmd_config sent to the command processing module in
1549  *   the libertas_prepare_and_send_command to configure a cmd_ds_802_11_scan command
1550  *   struct to send to firmware.
1551  *
1552  *  The fixed fields specifying the BSS type and BSSID filters as well as a
1553  *   variable number/length of TLVs are sent in the command to firmware.
1554  *
1555  *  @param priv       A pointer to wlan_private structure
1556  *  @param cmd        A pointer to cmd_ds_command structure to be sent to
1557  *                    firmware with the cmd_DS_801_11_SCAN structure
1558  *  @param pdata_buf  Void pointer cast of a wlan_scan_cmd_config struct used
1559  *                    to set the fields/TLVs for the command sent to firmware
1560  *
1561  *  @return           0 or -1
1562  *
1563  *  @sa wlan_scan_create_channel_list
1564  */
1565 int libertas_cmd_80211_scan(wlan_private * priv,
1566                          struct cmd_ds_command *cmd, void *pdata_buf)
1567 {
1568         struct cmd_ds_802_11_scan *pscan = &cmd->params.scan;
1569         struct wlan_scan_cmd_config *pscancfg;
1570
1571         lbs_deb_enter(LBS_DEB_ASSOC);
1572
1573         pscancfg = pdata_buf;
1574
1575         /* Set fixed field variables in scan command */
1576         pscan->bsstype = pscancfg->bsstype;
1577         memcpy(pscan->bssid, pscancfg->bssid, ETH_ALEN);
1578         memcpy(pscan->tlvbuffer, pscancfg->tlvbuffer, pscancfg->tlvbufferlen);
1579
1580         cmd->command = cpu_to_le16(CMD_802_11_SCAN);
1581
1582         /* size is equal to the sizeof(fixed portions) + the TLV len + header */
1583         cmd->size = cpu_to_le16(sizeof(pscan->bsstype) + ETH_ALEN
1584                                 + pscancfg->tlvbufferlen + S_DS_GEN);
1585
1586         lbs_deb_scan("SCAN_CMD: command=%x, size=%x, seqnum=%x\n",
1587                      le16_to_cpu(cmd->command), le16_to_cpu(cmd->size),
1588                      le16_to_cpu(cmd->seqnum));
1589
1590         lbs_deb_leave(LBS_DEB_ASSOC);
1591         return 0;
1592 }
1593
1594 static inline int is_same_network(struct bss_descriptor *src,
1595                                   struct bss_descriptor *dst)
1596 {
1597         /* A network is only a duplicate if the channel, BSSID, and ESSID
1598          * all match.  We treat all <hidden> with the same BSSID and channel
1599          * as one network */
1600         return ((src->ssid_len == dst->ssid_len) &&
1601                 (src->channel == dst->channel) &&
1602                 !compare_ether_addr(src->bssid, dst->bssid) &&
1603                 !memcmp(src->ssid, dst->ssid, src->ssid_len));
1604 }
1605
1606 /**
1607  *  @brief This function handles the command response of scan
1608  *
1609  *   The response buffer for the scan command has the following
1610  *      memory layout:
1611  *
1612  *     .-----------------------------------------------------------.
1613  *     |  header (4 * sizeof(u16)):  Standard command response hdr |
1614  *     .-----------------------------------------------------------.
1615  *     |  bufsize (u16) : sizeof the BSS Description data          |
1616  *     .-----------------------------------------------------------.
1617  *     |  NumOfSet (u8) : Number of BSS Descs returned             |
1618  *     .-----------------------------------------------------------.
1619  *     |  BSSDescription data (variable, size given in bufsize)    |
1620  *     .-----------------------------------------------------------.
1621  *     |  TLV data (variable, size calculated using header->size,  |
1622  *     |            bufsize and sizeof the fixed fields above)     |
1623  *     .-----------------------------------------------------------.
1624  *
1625  *  @param priv    A pointer to wlan_private structure
1626  *  @param resp    A pointer to cmd_ds_command
1627  *
1628  *  @return        0 or -1
1629  */
1630 int libertas_ret_80211_scan(wlan_private * priv, struct cmd_ds_command *resp)
1631 {
1632         wlan_adapter *adapter = priv->adapter;
1633         struct cmd_ds_802_11_scan_rsp *pscan;
1634         struct bss_descriptor * iter_bss;
1635         struct bss_descriptor * safe;
1636         u8 *pbssinfo;
1637         u16 scanrespsize;
1638         int bytesleft;
1639         int idx;
1640         int tlvbufsize;
1641         int ret;
1642
1643         lbs_deb_enter(LBS_DEB_ASSOC);
1644
1645         /* Prune old entries from scan table */
1646         list_for_each_entry_safe (iter_bss, safe, &adapter->network_list, list) {
1647                 unsigned long stale_time = iter_bss->last_scanned + DEFAULT_MAX_SCAN_AGE;
1648                 if (time_before(jiffies, stale_time))
1649                         continue;
1650                 list_move_tail (&iter_bss->list, &adapter->network_free_list);
1651                 clear_bss_descriptor(iter_bss);
1652         }
1653
1654         pscan = &resp->params.scanresp;
1655
1656         if (pscan->nr_sets > MAX_NETWORK_COUNT) {
1657                 lbs_deb_scan(
1658                        "SCAN_RESP: too many scan results (%d, max %d)!!\n",
1659                        pscan->nr_sets, MAX_NETWORK_COUNT);
1660                 ret = -1;
1661                 goto done;
1662         }
1663
1664         bytesleft = le16_to_cpu(pscan->bssdescriptsize);
1665         lbs_deb_scan("SCAN_RESP: bssdescriptsize %d\n", bytesleft);
1666
1667         scanrespsize = le16_to_cpu(resp->size);
1668         lbs_deb_scan("SCAN_RESP: returned %d AP before parsing\n",
1669                pscan->nr_sets);
1670
1671         pbssinfo = pscan->bssdesc_and_tlvbuffer;
1672
1673         /* The size of the TLV buffer is equal to the entire command response
1674          *   size (scanrespsize) minus the fixed fields (sizeof()'s), the
1675          *   BSS Descriptions (bssdescriptsize as bytesLef) and the command
1676          *   response header (S_DS_GEN)
1677          */
1678         tlvbufsize = scanrespsize - (bytesleft + sizeof(pscan->bssdescriptsize)
1679                                      + sizeof(pscan->nr_sets)
1680                                      + S_DS_GEN);
1681
1682         /*
1683          *  Process each scan response returned (pscan->nr_sets).  Save
1684          *    the information in the newbssentry and then insert into the
1685          *    driver scan table either as an update to an existing entry
1686          *    or as an addition at the end of the table
1687          */
1688         for (idx = 0; idx < pscan->nr_sets && bytesleft; idx++) {
1689                 struct bss_descriptor new;
1690                 struct bss_descriptor * found = NULL;
1691                 struct bss_descriptor * oldest = NULL;
1692
1693                 /* Process the data fields and IEs returned for this BSS */
1694                 memset(&new, 0, sizeof (struct bss_descriptor));
1695                 if (libertas_process_bss(&new, &pbssinfo, &bytesleft) != 0) {
1696                         /* error parsing the scan response, skipped */
1697                         lbs_deb_scan("SCAN_RESP: process_bss returned ERROR\n");
1698                         continue;
1699                 }
1700
1701                 /* Try to find this bss in the scan table */
1702                 list_for_each_entry (iter_bss, &adapter->network_list, list) {
1703                         if (is_same_network(iter_bss, &new)) {
1704                                 found = iter_bss;
1705                                 break;
1706                         }
1707
1708                         if ((oldest == NULL) ||
1709                             (iter_bss->last_scanned < oldest->last_scanned))
1710                                 oldest = iter_bss;
1711                 }
1712
1713                 if (found) {
1714                         /* found, clear it */
1715                         clear_bss_descriptor(found);
1716                 } else if (!list_empty(&adapter->network_free_list)) {
1717                         /* Pull one from the free list */
1718                         found = list_entry(adapter->network_free_list.next,
1719                                            struct bss_descriptor, list);
1720                         list_move_tail(&found->list, &adapter->network_list);
1721                 } else if (oldest) {
1722                         /* If there are no more slots, expire the oldest */
1723                         found = oldest;
1724                         clear_bss_descriptor(found);
1725                         list_move_tail(&found->list, &adapter->network_list);
1726                 } else {
1727                         continue;
1728                 }
1729
1730                 lbs_deb_scan("SCAN_RESP: BSSID = " MAC_FMT "\n",
1731                        new.bssid[0], new.bssid[1], new.bssid[2],
1732                        new.bssid[3], new.bssid[4], new.bssid[5]);
1733
1734                 /* Copy the locally created newbssentry to the scan table */
1735                 memcpy(found, &new, offsetof(struct bss_descriptor, list));
1736         }
1737
1738         ret = 0;
1739
1740 done:
1741         lbs_deb_leave_args(LBS_DEB_SCAN, "ret %d", ret);
1742         return ret;
1743 }