How to get other bss information from ndisuio?

Hello expert,

I meet a tricky problem to get the multiple AP's information detected by local 802.11 NIC.  When I prase the data which is returned from kernel, only the information of first AP is correct.  I miss the address of other AP.

The data sturctures defined in "Ntddndis.h" are here:

typedef struct _NDIS_WLAN_BSSID
{
    ULONG                               Length;             // Length of this structure
    NDIS_802_11_MAC_ADDRESS             MacAddress;         // BSSID
    UCHAR                               Reserved[2];
    NDIS_802_11_SSID                    Ssid;               // SSID
    ULONG                               Privacy;            // WEP encryption requirement
    NDIS_802_11_RSSI                    Rssi;               // receive signal
                                                            // strength in dBm
    NDIS_802_11_NETWORK_TYPE            NetworkTypeInUse;
    NDIS_802_11_CONFIGURATION           Configuration;
    NDIS_802_11_NETWORK_INFRASTRUCTURE  InfrastructureMode;
    NDIS_802_11_RATES                   SupportedRates;
} NDIS_WLAN_BSSID, *PNDIS_WLAN_BSSID;

typedef struct _NDIS_802_11_BSSID_LIST
{
    ULONG           NumberOfItems;      // in list below, at least 1
    NDIS_WLAN_BSSID Bssid[1];
} NDIS_802_11_BSSID_LIST, *PNDIS_802_11_BSSID_LIST;


The code to access NDIS_802_11_BSSID_LIST:

NDIS_STATUS            Dot11_GetAPList(
      HANDLE      handle,
      DOT11_BSS_LIST *pBssList )
{
      UCHAR                                    buf[4096];
      PNDISUIO_QUERY_OID                  pQueryOid;
      PNDISUIO_SET_OID                  pSetOid;
      PNDIS_802_11_BSSID_LIST            pBssid_List;
      ULONG                                    i = 0;
      int                                          j = 0;
      NDIS_STATUS                              status = S_OK;
      DWORD                                    dwBytesReturned = 0;
      DWORD                                    dwErrorCode = 0;
      int                                          bufSize;
      AP_DATA                                    *pTempApData = NULL;
      NDIS_WLAN_BSSID                  *pBssId = NULL;
      

      if (!pBssList )
      {
            status = E_POINTER;
      }

      else
      {
            pSetOid = (PNDISUIO_SET_OID) &buf[0];
            pSetOid->Oid = OID_802_11_BSSID_LIST_SCAN;
            
      
            if (!DeviceIoControl(
                              handle,
                              IOCTL_NDISUIO_SET_OID_VALUE,
                              (LPVOID) &buf[0],
                              sizeof(buf),                  // BUGBUG: ??
                              (LPVOID) &buf[0],
                              0,
                              &dwBytesReturned,
                              NULL))
            {
                  dwErrorCode = GetLastError();
                  DEBUGP(("IOCTL SET BSSID_LIST_SCAN failed: %d\n", dwErrorCode));
                  status = E_FAIL;
            }

            pQueryOid = (PNDISUIO_QUERY_OID) &buf[0];
            pQueryOid->Oid = OID_802_11_BSSID_LIST;

            if (DeviceIoControl(
                              handle,
                              IOCTL_NDISUIO_QUERY_OID_VALUE,
                              (LPVOID) &buf[0],
                              sizeof(buf),                  // BUGBUG: ??
                              (LPVOID) &buf[0],
                              sizeof(buf),
                              &dwBytesReturned,
                              NULL))
            {
                  DEBUGP(("IOCTL BSSID_LIST succeeded\n"));

                  pBssid_List = (PNDIS_802_11_BSSID_LIST)pQueryOid->Data;

                  pBssList->size = pBssid_List->NumberOfItems;
                  pBssList->pAP_Data = calloc( pBssid_List->NumberOfItems, sizeof(AP_DATA));

                  PRINTF(("\n\n===========  802.11 BSS List ==============\n"));
                  PRINTF(( "ID\tMAC\t\t\tRSSI(dBm)\tBSSID\n" ));      


                  for ( i = 0; i < pBssid_List->NumberOfItems; i++ )
                  {                        
                        pTempApData = &pBssList->pAP_Data[i] ;
                  
                        for ( j = 0; j < MAC_ADDR_LEN; j++ )
                        {
                              pTempApData->mac_addr[j] = (pBssid_List->Bssid[i]).MacAddress[j];
                        }

                        pTempApData->Rssi = (pBssid_List->Bssid[i]).Rssi;

                        PRINTF(( "%2u\t", i ));

                        PRINTF(("%02X-%02X-%02X-%02X-%02X-%02X",
                              (pBssid_List->Bssid[i]).MacAddress[0],
                              (pBssid_List->Bssid[i]).MacAddress[1],
                              (pBssid_List->Bssid[i]).MacAddress[2],
                              (pBssid_List->Bssid[i]).MacAddress[3],
                              (pBssid_List->Bssid[i]).MacAddress[4],
                              (pBssid_List->Bssid[i]).MacAddress[5] ));

                        PRINTF(( "\t%d", (pBssid_List->Bssid[i]).Rssi));

                        PRINTF(( "\t\t%s\n", (pBssid_List->Bssid[i]).Ssid.Ssid));

                  }                  
            }
            else
            {
                  status = E_FAIL;
                  dwErrorCode = GetLastError();
                  DEBUGP(("IOCTL BSSID_LIST failed: %d\n", dwErrorCode));
            }            
      }

      return status;

} //Dot11_GetAPList


Here is the output reslut:
===========  802.11 BSS List ==============
ID      MAC                            RSSI(dBm)  BSSID
 0      00-02-2D-B4-32-C2       -55             My Wireless Network A
 1      00-00-00-00-2C-00       33620758                v
 2      A5-FF-FF-FF-01-00       0               P
 3      28-40-00-00-04-00       3


According to the output, the first item in NDIS_802_11_BSSID_LIST struct, i.e, Bssid[0], is correct.  Unfortunately, I can not get the right address for Bssid[1] and Bssid[2].  How to get the right address?  Or the kernel only return the first AP's information indeed?

Thank you!

-Liang

typedef struct _NDIS_802_11_BSSID_LIST
{
    ULONG           NumberOfItems;      // in list below, at least 1
    NDIS_WLAN_BSSID Bssid[1];
} NDIS_802_11_BSSID_LIST, *PNDIS_802_11_BSSID_LIST;