NDIS driver: cloning a packet.

NTDEV
1

Hi to all!! in my delay-packets project i managed, with your help, to delay
packets handled by SendPacketHandler…
Now i’m tryng to delay packets handled by ReceivePAcketHandler too…
With my first solution, the same of sendpacket, system dosn t crash but
connection go closed, with no packet going in only one direction.
I think that s because i sent to timer only i pointer to the original
packet, as i ve done in sendPacket, without making a clone of it .

the aim is to make a clone of the packet, create a timer, pass to his
function the pointer to cloned packet, return 0 value to the handler…
so the problem is that i m not sure how to clone the packet:
i hve done in this way and system crash in NDis.sys:

this is the receivepackethandler function that i created and that will call
original function after a delay:

INT

PtReceivePacketEx(IN NDIS_HANDLE ProtocolBindingContext,IN PNDIS_PACKET
Packet){

PNDIS_TIMER timerRec = (PNDIS_TIMER)ExAllocatePool(NonPagedPool,
sizeof(NDIS_TIMER));

struct strutturaRec *strutRec = NULL;

UINT delayRec = 80;

PNDIS_STATUS Status=NULL;

PNDIS_BUFFER *Buffer=NULL;

NDIS_PACKET cloned = *Packet;

PNDIS_PACKET *pacc=NULL;

PADAPT pAdapt =(PADAPT)ProtocolBindingContext;

NDIS_PACKET *pcloned =ExAllocatePool(NonPagedPool, sizeof(NDIS_PACKET));

*pcloned=cloned;

NdisAllocateBuffer(Status, Buffer, pAdapt->handle,pcloned,
sizeof(NDIS_PACKET));

NdisAllocatePacket(Status, pacc, pAdapt->handle);

NdisChainBufferAtFront(*pacc,*Buffer);

if (timerRec == NULL){

ExFreePool(pcloned);

return 0;}

if (pcloned == NULL){

ExFreePool(timerRec);

return 0;}

strutRec = ExAllocatePool(NonPagedPool, sizeof(struct strutturaRec));

if (strutRec == NULL){

ExFreePool(pcloned);

ExFreePool(timerRec);

return 0;}

strutRec->pack=*pacc;

strutRec->pad=ProtocolBindingContext;

strutRec->timer = timerRec;

strutRec->Buf=*Buffer;

NdisInitializeTimer(timerRec,pippoRec,strutRec);

DbgPrint(“inizioritardoRec”);

NdisSetTimer(timerRec,delayRec);

DbgPrint(“DoporitardoRec”);

return 0;

}

this is the function that is called when timer expires:

VOID pippoRec(IN PVOID SystemSpecific1,IN PVOID FunctionContext,IN PVOID
SystemSpecific2,IN PVOID SystemSpecific3)

{

struct strutturaRec *punt= FunctionContext;

PtReceivePacketEx(punt->pad,punt->pack);

ExFreePool(punt->timer);

ExFreePool(punt->pack);

ExFreePool(punt->Buf);

ExFreePool(punt);

DbgPrint(“ritardo avvenutoRec”);

}

this is structure i created:

struct strutturaRec{

PNDIS_PACKET pack;

PNDIS_BUFFER Buf;

NDIS_HANDLE pad;

PVOID timer;

};

I added to ADAPT structure a NDIS_HANDLE variable, named handle, and
initialized it in PtBindAdapter after the initialization of
&pAdapt->RecvPacketPoolHandle

in this way:

NdisAllocatePacketPoolEx(Status,

&pAdapt->handle,

MIN_PACKET_POOL_SIZE,

MAX_PACKET_POOL_SIZE - MIN_PACKET_POOL_SIZE,

PROTOCOL_RESERVED_SIZE_IN_PACKET);

if (*Status != NDIS_STATUS_SUCCESS)

{

break;

}

any suggestions??

thanks anyway…

Francesco

2

I think you need to read the “NDIS Packet Discussion” at NDIS.com. See the URL:

http://www.ndis.com/papers/default.htm

Thomas F. Divine, Windows DDK MVP
http://www.pcausa.com

“Francesco Tabbita (IT)” wrote in message news:xxxxx@ntdev…
Hi to all!! in my delay-packets project i managed, with your help, to delay packets handled by SendPacketHandler…
Now i’m tryng to delay packets handled by ReceivePAcketHandler too…
With my first solution, the same of sendpacket, system dosn t crash but connection go closed, with no packet going in only one direction.
I think that s because i sent to timer only i pointer to the original packet, as i ve done in sendPacket, without making a clone of it .

the aim is to make a clone of the packet, create a timer, pass to his function the pointer to cloned packet, return 0 value to the handler…
so the problem is that i m not sure how to clone the packet:
i hve done in this way and system crash in NDis.sys:

this is the receivepackethandler function that i created and that will call original function after a delay:

INT

PtReceivePacketEx(IN NDIS_HANDLE ProtocolBindingContext,IN PNDIS_PACKET Packet){

PNDIS_TIMER timerRec = (PNDIS_TIMER)ExAllocatePool(NonPagedPool, sizeof(NDIS_TIMER));

struct strutturaRec *strutRec = NULL;

UINT delayRec = 80;

PNDIS_STATUS Status=NULL;

PNDIS_BUFFER *Buffer=NULL;

NDIS_PACKET cloned = *Packet;

PNDIS_PACKET *pacc=NULL;

PADAPT pAdapt =(PADAPT)ProtocolBindingContext;

NDIS_PACKET *pcloned =ExAllocatePool(NonPagedPool, sizeof(NDIS_PACKET));

*pcloned=cloned;

NdisAllocateBuffer(Status, Buffer, pAdapt->handle,pcloned, sizeof(NDIS_PACKET));

NdisAllocatePacket(Status, pacc, pAdapt->handle);

NdisChainBufferAtFront(*pacc,*Buffer);

if (timerRec == NULL){

ExFreePool(pcloned);

return 0;}

if (pcloned == NULL){

ExFreePool(timerRec);

return 0;}

strutRec = ExAllocatePool(NonPagedPool, sizeof(struct strutturaRec));

if (strutRec == NULL){

ExFreePool(pcloned);

ExFreePool(timerRec);

return 0;}

strutRec->pack=*pacc;

strutRec->pad=ProtocolBindingContext;

strutRec->timer = timerRec;

strutRec->Buf=*Buffer;

NdisInitializeTimer(timerRec,pippoRec,strutRec);

DbgPrint(“inizioritardoRec”);

NdisSetTimer(timerRec,delayRec);

DbgPrint(“DoporitardoRec”);

return 0;

}

this is the function that is called when timer expires:

VOID pippoRec(IN PVOID SystemSpecific1,IN PVOID FunctionContext,IN PVOID SystemSpecific2,IN PVOID SystemSpecific3)

{

struct strutturaRec *punt= FunctionContext;

PtReceivePacketEx(punt->pad,punt->pack);

ExFreePool(punt->timer);

ExFreePool(punt->pack);

ExFreePool(punt->Buf);

ExFreePool(punt);

DbgPrint(“ritardo avvenutoRec”);

}

this is structure i created:

struct strutturaRec{

PNDIS_PACKET pack;

PNDIS_BUFFER Buf;

NDIS_HANDLE pad;

PVOID timer;

};

I added to ADAPT structure a NDIS_HANDLE variable, named handle, and initialized it in PtBindAdapter after the initialization of &pAdapt->RecvPacketPoolHandle

in this way:

NdisAllocatePacketPoolEx(Status,

&pAdapt->handle,

MIN_PACKET_POOL_SIZE,

MAX_PACKET_POOL_SIZE - MIN_PACKET_POOL_SIZE,

PROTOCOL_RESERVED_SIZE_IN_PACKET);

if (*Status != NDIS_STATUS_SUCCESS)

{

break;

}

any suggestions??

thanks anyway…

Francesco