DOT11EXT_ONEX_START callback function

Important  The Native 802.11 Wireless LAN interface is deprecated in Windows 10 and later. Please use the WLAN Device Driver Interface (WDI) instead. For more information about WDI, see WLAN Universal Windows driver model.
The IHV Extensions DLL calls the Dot11ExtStartOneX function to initiate an 802.1X authentication operation with the access point (AP). In this situation, the authentication is managed by the 802.1X module of the Native 802.11 framework instead of by the IHV Extensions DLL.


DOT11EXT_ONEX_START Dot11extOnexStart;

DWORD Dot11extOnexStart(
  HANDLE hDot11SvcHandle,
  EAP_ATTRIBUTES *pEapAttributes



The handle used by the operating system to reference the wireless LAN (WLAN) adapter. This handle value was specified through a previous call to the Dot11ExtIhvInitAdapter IHV Handler function.


Return Value

If the call succeeds, the function returns ERROR_SUCCESS. Otherwise, it returns an error code defined in Winerror.h.


The IHV Extensions DLL can initiate an 802.1X authentication operation by using the 802.1X module of the Native 802.11 framework. This allows the DLL to use the standard extensible authentication protocol (EAP) algorithms that are supported by the operating system.

The IHV Extensions DLL initiates the 802.1X authentication operation by calling the Dot11ExtStartOneX function. Dot11ExtStartOneX can only be called either during a post-association operation or after the operation has completed. For more information about this operation, see Post-Association Operations.

When the Dot11ExtStartOneX function is called, the operating system sends an EAP over LAN (EAPOL) Start packet to the AP. If the AP fails to respond after three transmissions of the EAPOL-Start packet, the operating system fails the 802.1X authentication operation and calls the Dot11ExtIhvOneXIndicateResult IHV Handler function. For more information about the EAPOL-Start packet, refer to Clause 7.5 and Clause 8.4.2 of the IEEE 802.1X-1999 standard.

After the 802.1X authentication operation is initiated, the IHV Extensions DLL must follow these guidelines.

  • The IHV Extensions must forward all EAPOL packets to the operating system for processing. When the DLL receives an EAPOL packet through a call to the Dot11ExtIhvReceivePacket IHV Handler function, the DLL must call Dot11ExtProcessOneXPacket to forward the packet to the operating system.

    For more information about EAPOL packets, refer to Clause 7 of the IEEE 802.1X-2001 standard.

    Note  The IHV Extensions DLL is responsible for processing EAPOL-Key packets and must not forward these to the operating system.
  • When the 802.1X authentication operation is completed, the operating system calls the Dot11ExtIhvOneXIndicateResult IHV Handler function to indicate that authorization is in progress.
  • The IHV Extensions DLL can cancel the 802.1X authentication operation by calling Dot11ExtStopOneX.
For more information about using the 802.1X module for authentication, see Interface to the Native 802.11 802.1X Module.


Minimum supported client Available in Windows Vista and later versions of the Windows operating systems.
Target Platform Desktop
Header wlanihv.h (include Wlanihv.h)

See Also





Dot11ExtIhvOneXIndicateResult Dot11ExtIhvPerformPostAssociate