WLAN API for getting signal strenth

Question

I am using WLAN Api i.e WlanGetAvailableNetworkList() for signal strength of wireless lan modem/USB datacard.If somebody have some sample code example or some information pl

Answer 1

If you are using Python, there is sample code here.

If you are using C++, the documentation provides a good example:

#define UNICODE

#include <windows.h>
#include <wlanapi.h>
#include <objbase.h>
#include <wtypes.h>

#include <stdio.h>
#include <stdlib.h>

// Need to link with Wlanapi.lib and Ole32.lib
#pragma comment(lib, "wlanapi.lib")
#pragma comment(lib, "ole32.lib")


int wmain()
{

    // Declare and initialize variables.

    HANDLE hClient = NULL;
    DWORD dwMaxClient = 2;      //    
    DWORD dwCurVersion = 0;
    DWORD dwResult = 0;
    DWORD dwRetVal = 0;
    int iRet = 0;

    WCHAR GuidString[39] = {0};

    unsigned int i, j, k;

    /* variables used for WlanEnumInterfaces  */

    PWLAN_INTERFACE_INFO_LIST pIfList = NULL;
    PWLAN_INTERFACE_INFO pIfInfo = NULL;

    PWLAN_AVAILABLE_NETWORK_LIST pBssList = NULL;
    PWLAN_AVAILABLE_NETWORK pBssEntry = NULL;

    dwResult = WlanOpenHandle(dwMaxClient, NULL, &dwCurVersion, &hClient);
    if (dwResult != ERROR_SUCCESS) {
        wprintf(L"WlanOpenHandle failed with error: %u\n", dwResult);
        return 1;
        // You can use FormatMessage here to find out why the function failed
    }

    dwResult = WlanEnumInterfaces(hClient, NULL, &pIfList);
    if (dwResult != ERROR_SUCCESS) {
        wprintf(L"WlanEnumInterfaces failed with error: %u\n", dwResult);
        return 1;
        // You can use FormatMessage here to find out why the function failed
    } else {
        wprintf(L"Num Entries: %lu\n", pIfList->dwNumberOfItems);
        wprintf(L"Current Index: %lu\n", pIfList->dwIndex);
        for (i = 0; i < (int) pIfList->dwNumberOfItems; i++) {
            pIfInfo = (WLAN_INTERFACE_INFO *) &pIfList->InterfaceInfo[i];
            wprintf(L"  Interface Index[%u]:\t %lu\n", i, i);
            iRet = StringFromGUID2(pIfInfo->InterfaceGuid, (LPOLESTR) &GuidString, 
                sizeof(GuidString)/sizeof(*GuidString)); 
            // For c rather than C++ source code, the above line needs to be
            // iRet = StringFromGUID2(&pIfInfo->InterfaceGuid, (LPOLESTR) &GuidString, 
            //     sizeof(GuidString)/sizeof(*GuidString)); 
            if (iRet == 0)
                wprintf(L"StringFromGUID2 failed\n");
            else {
                wprintf(L"  InterfaceGUID[%d]: %ws\n",i, GuidString);
            }    
            wprintf(L"  Interface Description[%d]: %ws", i, 
                pIfInfo->strInterfaceDescription);
            wprintf(L"\n");
            wprintf(L"  Interface State[%d]:\t ", i);
            switch (pIfInfo->isState) {
            case wlan_interface_state_not_ready:
                wprintf(L"Not ready\n");
                break;
            case wlan_interface_state_connected:
                wprintf(L"Connected\n");
                break;
            case wlan_interface_state_ad_hoc_network_formed:
                wprintf(L"First node in a ad hoc network\n");
                break;
            case wlan_interface_state_disconnecting:
                wprintf(L"Disconnecting\n");
                break;
            case wlan_interface_state_disconnected:
                wprintf(L"Not connected\n");
                break;
            case wlan_interface_state_associating:
                wprintf(L"Attempting to associate with a network\n");
                break;
            case wlan_interface_state_discovering:
                wprintf(L"Auto configuration is discovering settings for the network\n");
                break;
            case wlan_interface_state_authenticating:
                wprintf(L"In process of authenticating\n");
                break;
            default:
                wprintf(L"Unknown state %ld\n", pIfInfo->isState);
                break;
            }
            wprintf(L"\n");

            dwResult = WlanGetAvailableNetworkList(hClient,
                                             &pIfInfo->InterfaceGuid,
                                             0, 
                                             NULL, 
                                             &pBssList);

            if (dwResult != ERROR_SUCCESS) {
                wprintf(L"WlanGetAvailableNetworkList failed with error: %u\n",
                        dwResult);
                dwRetVal = 1;
                // You can use FormatMessage to find out why the function failed
            } else {
                wprintf(L"WLAN_AVAILABLE_NETWORK_LIST for this interface\n");

                wprintf(L"  Num Entries: %lu\n\n", pBssList->dwNumberOfItems);

                for (j = 0; j < pBssList->dwNumberOfItems; j++) {
                    pBssEntry =
                        (WLAN_AVAILABLE_NETWORK *) & pBssList->Network[j];

                    wprintf(L"  Profile Name[%u]:  %ws\n", j, pBssEntry->strProfileName);

                    wprintf(L"  SSID[%u]:\t\t ", j);
                    if (pBssEntry->dot11Ssid.uSSIDLength == 0)
                        wprintf(L"\n");
                    else {   
                        for (k = 0; k < pBssEntry->dot11Ssid.uSSIDLength; k++) {
                            wprintf(L"%c", (int) pBssEntry->dot11Ssid.ucSSID[k]);
                        }
                        wprintf(L"\n");
                    }

                    wprintf(L"  BSS Network type[%u]:\t ", j);
                    switch (pBssEntry->dot11BssType) {
                    case dot11_BSS_type_infrastructure   :
                        wprintf(L"Infrastructure (%u)\n", pBssEntry->dot11BssType);
                        break;
                    case dot11_BSS_type_independent:
                        wprintf(L"Infrastructure (%u)\n", pBssEntry->dot11BssType);
                        break;
                    default:
                        wprintf(L"Other (%lu)\n", pBssEntry->dot11BssType);
                        break;
                    }

                    wprintf(L"  Number of BSSIDs[%u]:\t %u\n", j, pBssEntry->uNumberOfBssids);

                    wprintf(L"  Connectable[%u]:\t ", j);
                    if (pBssEntry->bNetworkConnectable)
                        wprintf(L"Yes\n");
                    else
                        wprintf(L"No\n");

                    wprintf(L"  Signal Quality[%u]:\t %u\n", j, pBssEntry->wlanSignalQuality);

                    wprintf(L"  Security Enabled[%u]:\t ", j);
                    if (pBssEntry->bSecurityEnabled)
                        wprintf(L"Yes\n");
                    else
                        wprintf(L"No\n");

                    wprintf(L"  Default AuthAlgorithm[%u]: ", j);
                    switch (pBssEntry->dot11DefaultAuthAlgorithm) {
                    case DOT11_AUTH_ALGO_80211_OPEN:
                        wprintf(L"802.11 Open (%u)\n", pBssEntry->dot11DefaultAuthAlgorithm);
                        break;
                    case DOT11_AUTH_ALGO_80211_SHARED_KEY:
                        wprintf(L"802.11 Shared (%u)\n", pBssEntry->dot11DefaultAuthAlgorithm);
                        break;
                    case DOT11_AUTH_ALGO_WPA:
                        wprintf(L"WPA (%u)\n", pBssEntry->dot11DefaultAuthAlgorithm);
                        break;
                    case DOT11_AUTH_ALGO_WPA_PSK:
                        wprintf(L"WPA-PSK (%u)\n", pBssEntry->dot11DefaultAuthAlgorithm);
                        break;
                    case DOT11_AUTH_ALGO_WPA_NONE:
                        wprintf(L"WPA-None (%u)\n", pBssEntry->dot11DefaultAuthAlgorithm);
                        break;
                    case DOT11_AUTH_ALGO_RSNA:
                        wprintf(L"RSNA (%u)\n", pBssEntry->dot11DefaultAuthAlgorithm);
                        break;
                    case DOT11_AUTH_ALGO_RSNA_PSK:
                        wprintf(L"RSNA with PSK(%u)\n", pBssEntry->dot11DefaultAuthAlgorithm);
                        break;
                    default:
                        wprintf(L"Other (%lu)\n", pBssEntry->dot11DefaultAuthAlgorithm);
                        break;
                    }

                    wprintf(L"  Default CipherAlgorithm[%u]: ", j);
                    switch (pBssEntry->dot11DefaultCipherAlgorithm) {
                    case DOT11_CIPHER_ALGO_NONE:
                        wprintf(L"None (0x%x)\n", pBssEntry->dot11DefaultCipherAlgorithm);
                        break;
                    case DOT11_CIPHER_ALGO_WEP40:
                        wprintf(L"WEP-40 (0x%x)\n", pBssEntry->dot11DefaultCipherAlgorithm);
                        break;
                    case DOT11_CIPHER_ALGO_TKIP:
                        wprintf(L"TKIP (0x%x)\n", pBssEntry->dot11DefaultCipherAlgorithm);
                        break;
                    case DOT11_CIPHER_ALGO_CCMP:
                        wprintf(L"CCMP (0x%x)\n", pBssEntry->dot11DefaultCipherAlgorithm);
                        break;
                    case DOT11_CIPHER_ALGO_WEP104:
                        wprintf(L"WEP-104 (0x%x)\n", pBssEntry->dot11DefaultCipherAlgorithm);
                        break;
                    case DOT11_CIPHER_ALGO_WEP:
                        wprintf(L"WEP (0x%x)\n", pBssEntry->dot11DefaultCipherAlgorithm);
                        break;
                    default:
                        wprintf(L"Other (0x%x)\n", pBssEntry->dot11DefaultCipherAlgorithm);
                        break;
                    }

                    wprintf(L"\n");
                }
            }
        }

    }
    if (pBssList != NULL) {
        WlanFreeMemory(pBssList);
        pBssList = NULL;
    }

    if (pIfList != NULL) {
        WlanFreeMemory(pIfList);
        pIfList = NULL;
    }

    return dwRetVal;
}

Answer 2

You can use the DeviceIoControl function with OID_802_11_RSSI to query RSSI.