VOID ICMPTransmit(
PIP_PACKET IPPacket,
PIP_TRANSMIT_COMPLETE Complete,
PVOID Context)
/*
* FUNCTION: Transmits an ICMP packet
* ARGUMENTS:
* NTE = Pointer to net table entry to use (NULL if don't care)
* IPPacket = Pointer to IP packet to transmit
*/
{
PNEIGHBOR_CACHE_ENTRY NCE;
TI_DbgPrint(DEBUG_ICMP, ("Called.\n"));
/* Calculate checksum of ICMP header and data */
((PICMP_HEADER)IPPacket->Data)->Checksum = (USHORT)
IPv4Checksum(IPPacket->Data, IPPacket->TotalSize - IPPacket->HeaderSize, 0);
/* Get a route to the destination address */
if ((NCE = RouteGetRouteToDestination(&IPPacket->DstAddr))) {
/* Send the packet */
IPSendDatagram(IPPacket, NCE);
} else {
/* No route to destination (or no free resources) */
TI_DbgPrint(DEBUG_ICMP, ("No route to destination address 0x%X.\n",
IPPacket->DstAddr.Address.IPv4Address));
IPPacket->Free(IPPacket);
}
}
BOOLEAN PrepareNextFragment(
PIPFRAGMENT_CONTEXT IFC)
/*
* FUNCTION: Prepares the next fragment of an IP datagram for transmission
* ARGUMENTS:
* IFC = Pointer to IP fragment context
* RETURNS:
* TRUE if a fragment was prepared for transmission, FALSE if
* there are no more fragments to send
*/
{
UINT MaxData;
UINT DataSize;
PIPv4_HEADER Header;
BOOLEAN MoreFragments;
USHORT FragOfs;
TI_DbgPrint(MAX_TRACE, ("Called. IFC (0x%X)\n", IFC));
if (IFC->BytesLeft > 0) {
TI_DbgPrint(MAX_TRACE, ("Preparing 1 fragment.\n"));
MaxData = IFC->PathMTU - IFC->HeaderSize;
/* Make fragment a multiplum of 64bit */
MaxData -= MaxData % 8;
if (IFC->BytesLeft > MaxData) {
DataSize = MaxData;
MoreFragments = TRUE;
} else {
DataSize = IFC->BytesLeft;
MoreFragments = FALSE;
}
TI_DbgPrint(MID_TRACE,("Copying data from %x to %x (%d)\n",
IFC->DatagramData, IFC->Data, DataSize));
RtlCopyMemory(IFC->Data, IFC->DatagramData, DataSize); // SAFE
/* Fragment offset is in 8 byte blocks */
FragOfs = (USHORT)(IFC->Position / 8);
if (MoreFragments)
FragOfs |= IPv4_MF_MASK;
else
FragOfs &= ~IPv4_MF_MASK;
Header = IFC->Header;
Header->FlagsFragOfs = WH2N(FragOfs);
Header->TotalLength = WH2N((USHORT)(DataSize + IFC->HeaderSize));
/* FIXME: Handle options */
/* Calculate checksum of IP header */
Header->Checksum = 0;
Header->Checksum = (USHORT)IPv4Checksum(Header, IFC->HeaderSize, 0);
TI_DbgPrint(MID_TRACE,("IP Check: %x\n", Header->Checksum));
/* Update pointers */
IFC->DatagramData = (PVOID)((ULONG_PTR)IFC->DatagramData + DataSize);
IFC->Position += DataSize;
IFC->BytesLeft -= DataSize;
return TRUE;
} else {
TI_DbgPrint(MAX_TRACE, ("No more fragments.\n"));
return FALSE;
}
}
