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This value is filled using KeQuerySystemTime (equal to user-mode NtQuerySystemTime). Here is the short description:
“System time is a count of 100-nanosecond intervals since January 1, 1601. System time is typically updated approximately every ten milliseconds. This value is computed for the GMT time zone.” (Windows DDK help)
In order to convert the m_SystemTime to SYSTEMTIME structure do the following:
1) Copy m_SystemTime to FILETIME structure (don’t use simple typecast, because alignment can be different).
2) Call FileTimeToSystemTime.If you control DeviceTcp, DeviceUdp, DeviceIp, DeviceRawIp and DeviceMULTICAST then you have complete control over application’s (IE, ICQ, Outlook and etc…) access to the MS TCP/IP network stack. Under control I mean ability to block any network activity (create socket, listen port, connect remote host and et…). Is that your question?
But this does not mean that you control all network activity of the system, because it may have another network protocols installed (IPv6 an example). But even without installing additional protocols, control over TDI is not the same as control over network. If you try to block the network with your TDI filter then MS TCP/IP still continue packet routing, it still replies ICMP ping, network file and folder sharing still works and etc… This is because mentioned network activities never reach TDI level.
I hope I’ve answered your question…
I don’t understand what actually you mean under “control control the network of the system”. Please clarify if you need the correct answer…
I have not code for WinpkFilter, but the routines below demonstrate how I did it in Ethernet Bridge. Doing this using WinpkFilter is very similar. Please note, that you should also set NDIS flags NDIS_FLAGS_SKIP_LOOPBACK | NDIS_FLAGS_DONT_LOOPBACK before sending the packet over the network in order to avoid it to indicated back (in the code below it is done inside UF_SendPacketToAdapter but I did not provided it).
VOID FLT_FilterReceivedPacket (
NDIS_HANDLE NdisBindingHandle,
PINTERMEDIATE_BUFFER pBuffer
)
{
// Processing relative declarations
PUSHORT pEtherType;
//Adapter and protocol relative structures
PPROTOCOL_ENTRY pProto;
PADAPTER_ENTRY pAdapter, pReceivedAdapter;
DbgPrint ( "FLT_FilterReceivedPacket pBuffer->m_Lengh = %d...n", pBuffer->m_Length );
// DbgPrint ( "FLT_FilterReceivedPacket entered...n" );
// .... process packet here....
// We dump packet content here
//DbgPrint ("nRCV:n");
//DbgPrint ("MACS: DEST %.2X%.2X%.2X%.2X%.2X%.2X SOURCE: %.2X%.2X%.2X%.2X%.2X%.2Xn",
// pBuffer->m_IBuffer[0],
// pBuffer->m_IBuffer[1],
// pBuffer->m_IBuffer[2],
// pBuffer->m_IBuffer[3],
// pBuffer->m_IBuffer[4],
// pBuffer->m_IBuffer[5],
// pBuffer->m_IBuffer[6],
// pBuffer->m_IBuffer[7],
// pBuffer->m_IBuffer[8],
// pBuffer->m_IBuffer[9],
// pBuffer->m_IBuffer[10],
// pBuffer->m_IBuffer[11]
// );
pEtherType = (PUSHORT) pBuffer->m_IBuffer;
pEtherType += ETH_LENGTH_OF_ADDRESS;
/* switch( htons( *pEtherType ) )
{
case ETHERTYPE_IP:
DbgPrint ("IP packet: ");
ipHdr = ( PIP_HEADER ) &pBuffer->m_IBuffer[MHdrSize];
DbgPrint ( " %u.%u.%u.%u ---> %u.%u.%u.%un",
(ipHdr->ip_src.S_un.S_un_b.s_b1),
(ipHdr->ip_src.S_un.S_un_b.s_b2),
(ipHdr->ip_src.S_un.S_un_b.s_b3),
(ipHdr->ip_src.S_un.S_un_b.s_b4),
(ipHdr->ip_dst.S_un.S_un_b.s_b1),
(ipHdr->ip_dst.S_un.S_un_b.s_b2),
(ipHdr->ip_dst.S_un.S_un_b.s_b3),
(ipHdr->ip_dst.S_un.S_un_b.s_b4)
);
break;
case ETHERTYPE_ARP:
DbgPrint ("ARP packet:");
arpPkt = ( PARP_PACKET ) pBuffer->m_IBuffer;
DbgPrint ( " %u.%u.%u.%u ---> %u.%u.%u.%u ?n",
(arpPkt->ea.arp_spa[0]),
(arpPkt->ea.arp_spa[1]),
(arpPkt->ea.arp_spa[2]),
(arpPkt->ea.arp_spa[3]),
(arpPkt->ea.arp_tpa[0]),
(arpPkt->ea.arp_tpa[1]),
(arpPkt->ea.arp_tpa[2]),
(arpPkt->ea.arp_tpa[3])
);
break;
case ETHERTYPE_REVARP:
DbgPrint ("REVARP packet:n");
break;
default:
DbgPrint ("Uknown type n");
}*/
// Simply indicate packet to protocol
UF_SendPacketToProtocol (
NdisBindingHandle,
pBuffer->m_IBuffer,
pBuffer->m_Length
);
// Send packet to all other network interfaces if bridging enabled
if ( g_BridgingStatus )
{
// Locate adapter and protocol entryes associated with operation
pReceivedAdapter = MF_FindAdapterByBindingHandle( NdisBindingHandle, &pProto);
pAdapter = ( PADAPTER_ENTRY ) pProto -> m_AdaptersList.Flink;
// Walk the list of binded adapters
while ( pAdapter != ( PADAPTER_ENTRY ) &pProto -> m_AdaptersList )
{
if ( pAdapter != pReceivedAdapter)
{
// Packet was receved not from this adapter
// Simply send packet onto this interface
// DbgPrint ("Duplicating packet on the another interface...n");
if (osMajorVersion == 5 && osMinorVersion > 0)
UF_SendPacketToAdapter ( &pAdapter->m_XPOpenBlock, pBuffer );
else
UF_SendPacketToAdapter ( &pAdapter->m_W2kOpenBlock, pBuffer );
// Also indicate packet to TCPIP from the name of this interface
if (osMajorVersion == 5 && osMinorVersion > 0)
UF_SendPacketToProtocol (
&pAdapter->m_XPOpenBlock,
pBuffer->m_IBuffer,
pBuffer->m_Length
);
else
UF_SendPacketToProtocol (
&pAdapter->m_W2kOpenBlock,
pBuffer->m_IBuffer,
pBuffer->m_Length
);
}
pAdapter = (PADAPTER_ENTRY) pAdapter->m_qLink.Flink;
}
}
// Free intermediate buffer
IB_FreeIntermediateBuffer ( pBuffer );
}
//***********************************************************************************
// Name: FLT_FilterSendPacket
//
// Description: Routine for filtering outgoing packets, place packet processing code
// here
//
// Return value: None
//
// Parameters:
// NdisBindingHandle - network interface binding handle
// pBuffer - pointer to intermediate buffer
//
// NOTE: None
// **********************************************************************************
VOID FLT_FilterSendPacket (
NDIS_HANDLE NdisBindingHandle,
PINTERMEDIATE_BUFFER pBuffer
)
{
// Processing relative declarations
PUSHORT pEtherType;
//Adapter and protocol relative structures
PPROTOCOL_ENTRY pProto;
PADAPTER_ENTRY pAdapter, pSentAdapter;
DbgPrint ( "FLT_FilterSendPacket pBuffer->m_Lengh = %d...n", pBuffer->m_Length );
// DbgPrint ( "FLT_FilterSendPacket entered...n" );
// .... process packet here....
// We dump packet content here
// DbgPrint ("nSEND:n");
// DbgPrint ("MACS: DEST %.2X%.2X%.2X%.2X%.2X%.2X SOURCE: %.2X%.2X%.2X%.2X%.2X%.2Xn",
// pBuffer->m_IBuffer[0],
// pBuffer->m_IBuffer[1],
// pBuffer->m_IBuffer[2],
// pBuffer->m_IBuffer[3],
// pBuffer->m_IBuffer[4],
// pBuffer->m_IBuffer[5],
// pBuffer->m_IBuffer[6],
// pBuffer->m_IBuffer[7],
// pBuffer->m_IBuffer[8],
// pBuffer->m_IBuffer[9],
// pBuffer->m_IBuffer[10],
// pBuffer->m_IBuffer[11]
// );
pEtherType = (PUSHORT) pBuffer->m_IBuffer;
pEtherType += ETH_LENGTH_OF_ADDRESS;
/* switch( htons( *pEtherType ) )
{
case ETHERTYPE_IP:
DbgPrint ("IP packet: ");
ipHdr = ( PIP_HEADER ) &pBuffer->m_IBuffer[MHdrSize];
DbgPrint ( " %u.%u.%u.%u ---> %u.%u.%u.%un",
(ipHdr->ip_src.S_un.S_un_b.s_b1),
(ipHdr->ip_src.S_un.S_un_b.s_b2),
(ipHdr->ip_src.S_un.S_un_b.s_b3),
(ipHdr->ip_src.S_un.S_un_b.s_b4),
(ipHdr->ip_dst.S_un.S_un_b.s_b1),
(ipHdr->ip_dst.S_un.S_un_b.s_b2),
(ipHdr->ip_dst.S_un.S_un_b.s_b3),
(ipHdr->ip_dst.S_un.S_un_b.s_b4)
);
break;
case ETHERTYPE_ARP:
DbgPrint ("ARP packet:");
arpPkt = ( PARP_PACKET ) pBuffer->m_IBuffer;
DbgPrint ( " %u.%u.%u.%u ---> %u.%u.%u.%u ?n",
(arpPkt->ea.arp_spa[0]),
(arpPkt->ea.arp_spa[1]),
(arpPkt->ea.arp_spa[2]),
(arpPkt->ea.arp_spa[3]),
(arpPkt->ea.arp_tpa[0]),
(arpPkt->ea.arp_tpa[1]),
(arpPkt->ea.arp_tpa[2]),
(arpPkt->ea.arp_tpa[3])
);
break;
case ETHERTYPE_REVARP:
DbgPrint ("REVARP packet:n");
break;
default:
DbgPrint ("Uknown type n");
}*/
// Simply send packet onto network
UF_SendPacketToAdapter (
NdisBindingHandle,
pBuffer
);
// Send packet to all other network interfaces if bridging enabled
if ( g_BridgingStatus )
{
// Locate adapter and protocol entryes associated with operation
pSentAdapter = MF_FindAdapterByBindingHandle( NdisBindingHandle, &pProto);
pAdapter = ( PADAPTER_ENTRY ) pProto -> m_AdaptersList.Flink;
// Walk the list of binded adapters
while ( pAdapter != ( PADAPTER_ENTRY ) &pProto -> m_AdaptersList )
{
if ( pAdapter != pSentAdapter)
{
// Packet was sent not to this adapter
// Simply send packet onto this interface
// DbgPrint ("Duplicating packet on the another interface...n");
if (osMajorVersion == 5 && osMinorVersion > 0)
UF_SendPacketToAdapter (
&pAdapter->m_XPOpenBlock,
pBuffer
);
else
UF_SendPacketToAdapter (
&pAdapter->m_W2kOpenBlock,
pBuffer
);
}
pAdapter = (PADAPTER_ENTRY) pAdapter->m_qLink.Flink;
}
}
// Free intermediate buffer
IB_FreeIntermediateBuffer ( pBuffer );
}The code above do the following:
1) Release event for packet indication.
2) Set adapter into passthru mode (the state it was before you set TUNNEL mode).
3) Flush packet queue associated with the adapter.For temporary stop filtering: 1 – is not necessary, 2 – should be be done, otherwise (if you exited the loop) the network will be forzen after all WinpkFilter internal buffers are used, 3 – should be done because if you have existed packet reading loop, to that moment you can have internal buffer pool exosted and the network frozen.
So, in addition to exiting the loop you should set the default mode over the interface and flush its packet queue. If you want to restore filtering, then set tunnel mode and enter the loop again.
Please pay attention to the routine below (it is available in PassThru and PacketSniffer samples), which actually stops WinpkFillter operations over the network interface and releases resources:
void ReleaseInterface()
{
// This function releases packets in the adapter queue and stops listening the interface
ADAPTER_MODE Mode;
Mode.dwFlags = 0;
Mode.hAdapterHandle = (HANDLE)AdList.m_nAdapterHandle[iIndex];
// Set NULL event to release previously set event object
api.SetPacketEvent(AdList.m_nAdapterHandle[iIndex], NULL);
// Close Event
if (hEvent)
CloseHandle ( hEvent );
// Set default adapter mode
api.SetAdapterMode(&Mode);
// Empty adapter packets queue
api.FlushAdapterPacketQueue (AdList.m_nAdapterHandle[iIndex]);
}1) First issue with direct NDIS_OPEN_BLOCK modification works just like you have described. The only fix is hooking internal NDIS-routines and repatching the NDIS_OPEN_BLOCK each time when handlers are changed,
2) The second approach with substitution on NDIS_OPEN_BLOCK works fine, and in your case problem is somethere else, lines you have provided look OK.
In general NDIS hooking driver is relatively complicated and it is difficult to design such a driver from the scratch. So I would recommend to use one of the documented approaches (intermediate, filter hook or etc…) or license ready NDIS hooking solution instead of trying to create the new one.
If you ask about WinpkFilter, then you can do it using the SendPacketToMstcp (if you want packet to be indicated from the name of another interface to the local TCP/IP stack) and SendPacketToNetwork (if you want it to be sent over the network from the interface different from received one). For both calls you should use corresponding network interface handles, both routines can be called with difefrent handles for the same packet any times you want. One note, if you want to bridge WAN interface you should also modify MAC addresses in the packet (this is point-to-point connection and MAC’s are used to distinguish different connections), otherwise NDISWAN won’t be able to find the corresponding link and may even crash the system…
Yes, we are sorry. but older versions (before 2.4 series) may have problems when running on Windows XP SP2. It does not mean that you MUST have problems, but it is possible and depends of your software/hardware configuration.
WinpkFilter installation scripts (for Windows 2000/XP/2003) were updated in order to support compatibility with the latest released version of Kerio Personal Firewall. Details: Group:”Network” Start:0 were changed to Group: “Streams Drivers” Start:1.
WinpkFilter 2.4.1 released. This service release improves WinpkFilter support for some network interfaces (an example BUFFALO LPC4-CLX Fast Ethernet Adapter) under Windows 2000 and Millennium Edition. MS Visual Basic samples were also moved into the main package.
If you are eligible for a free update, please send the following details to support@ntkernel.com tо receive an update instruction:
1) Your order ID.
2) An approximate date of purchasing.
