private void UpdatePendingRequests(IPv4 ipAddress,
EthernetAddress macAddress)
{
using (pendingRequestsLock.Lock()) {
//Sigh...we're missing a linked list in the current Singularity C# runtime
foreach (PendingArpRequest pendingRequest in pendingRequests)
{
VTable.Assert(pendingRequest != null);
if (pendingRequest.address == ipAddress)
{
pendingRequest.active = false;
DebugStub.WriteLine("found waiting arp request...sending on out");
VectorQueueByte txBuffer = pendingRequest.txContainer.Acquire();
Bytes header = txBuffer.ExtractHead();
Bytes buffer = txBuffer.ExtractHead();
VTable.Assert(header != null);
VTable.Assert(buffer != null);
pendingRequest.txContainer.Release(txBuffer);
//Format ethernet header
EthernetHeader.Write(header, pendingRequest.localMac, macAddress, EthernetHeader.PROTOCOL_IP);
//send it!
VTable.Assert(pendingRequest.adapter != null);
pendingRequest.adapter.PopulateTxRing(header, buffer);
continue;
}
}
}
}
public void ArpRequest(IPv4 sourceIP,
IPv4 targetIP,
EthernetAddress localMac,
Bytes header,
Bytes buffer,
IAdapter adapter)
{
// AutoResetEvent requestComplete =
AddPendingRequest(targetIP, TimeSpan.FromSeconds(3), localMac, header, buffer, adapter);
// initiate an arp request...
DebugPrint("Initiating request " +
"({0},{1}) --> ({2},{3})\n",
sourceIP, localMac, targetIP, EthernetAddress.Zero);
//eventially we'll want to follow Orion's conservation of
//packets philosophy
Bytes arpHeader = new Bytes(new byte [EthernetHeader.Size]);
Bytes arpMsg = new Bytes(new byte [ArpHeader.Size]);
//xxx I'd like to get rid of EthernetHeader eventually...
EthernetHeader.Write(arpHeader,
localMac,
EthernetAddress.Broadcast,
EthernetHeader.PROTOCOL_ARP);
ArpHeader.Write(arpMsg, localMac, sourceIP,
ArpHeader.ARP_REQUEST, EthernetAddress.Zero,
targetIP);
adapter.PopulateTxRing(arpHeader, arpMsg);
// DebugPrint("ArpRequest: waiting for reply\n");
//requestComplete.WaitOne();
// DebugPrint("ArpRequest: reply received!\n");
}
internal bool Send(EthernetAddress dstAddr, DhcpFormat dhcp)
{
int packetSize = dhcp.Size;
int headerSize = EthernetHeader.Size + UDPHeader.Size + IpHeader.Size;
Bytes packet = new Bytes(new byte [packetSize]);
Bytes header = new Bytes(new byte [headerSize]);
// Write out DHCP packet
dhcp.Write(packet, 0);
//the correct ports/addresses should already be bound up in instance of the UDP object
udp.WriteCompleteUDPHeader(header, packet, dhcp.Size);
// Add Ethernet Header
EthernetHeader.Write(header, adapter.HardwareAddress,
dstAddr, EthernetHeader.PROTOCOL_IP);
adapter.PopulateTxRing(header, packet);
return(true);
}
// Original note from Yaron:
// ARP logic: see RFC 826 http://www.faqs.org/rfcs/rfc826.html
//
public void ProcessIncomingPacket(Bytes packet, IAdapter adapter)
{
//Get the ARP packet info located after the ethernet header
ArpHeader arpHeader = new ArpHeader(packet, 14);
DebugPrint("ARP: ProcessIncomingPacket\n");
//do some checks to make sure the packet is copacetic
if (arpHeader.htype != 0x1)
{
DebugPrint("ARP: ProcessIncomingPacket got wrong hardware type? 0x{0,8:x}\n",
arpHeader.htype);
//delete packet;
return;
}
if (arpHeader.ptype != 0x0800)
{
DebugPrint("ARP: ProcessIncomingPacket got wrong protocol? 0x{0,8:x}\n",
arpHeader.ptype);
//delete packet;
return;
}
//ethernet address should be 6 bytes
if (arpHeader.hlen != 6)
{
DebugPrint("ARP: ProcessIncomingPacket got wrong hw length? 0x{0,8:x}\n",
arpHeader.hlen);
//delete packet;
return;
}
if (arpHeader.plen != 4)
{
DebugPrint("ARP: ProcessIncomingPacket got wrong protocol address length? 0x{0,8:x}\n",
arpHeader.plen);
//delete packet;
return;
}
DebugPrint("Incoming packet\n");
bool merged = false;
bool updated = false;
ArpEntry target = arpTable.Lookup(arpHeader.senderIPAddr);
if (target != null && target.Dynamic == true)
{
DebugPrint("ARP UPDATE\n");
// we have it already - just update the details...
target.MacAddress = arpHeader.senderEthernetAddr;
target.EntryAge = arpTable.Age;
merged = true;
updated = true;
}
if (merged == false)
{
DebugPrint("ARP ADDITION\n");
arpTable.AddEntry(new ArpEntry(arpHeader.senderIPAddr,
arpHeader.senderEthernetAddr, true));
merged = true;
UpdatePendingRequests(arpHeader.senderIPAddr, arpHeader.senderEthernetAddr);
}
//Is this a local address
bool forSelf = IP.IsLocalAddress(arpHeader.destIPAddr);
if (forSelf == false)
{
//delete packet;
return;
}
// now figure out the opcode
if (arpHeader.op == ARP_REQUEST)
{
DebugPrint("Handling request ({0},{1}) ---> ({2},{3} \npkt dest {4} {5})\n",
arpHeader.senderIPAddr, arpHeader.senderEthernetAddr,
arpHeader.destIPAddr, adapter.HardwareAddress,
arpHeader.destIPAddr, arpHeader.destEthernetAddr
);
int dataLength = EthernetHeader.Size + ArpHeader.Size;
VTable.Assert(packet.Length >= dataLength);
Bytes data = Bitter.SplitOff(ref packet, EthernetHeader.Size);
EthernetHeader.Write(packet,
adapter.HardwareAddress,
arpHeader.senderEthernetAddr,
EthernetHeader.PROTOCOL_ARP);
//use arp header to format reply
ArpHeader.Write(data, adapter.HardwareAddress,
arpHeader.destIPAddr, ArpHeader.ARP_REPLY,
arpHeader.senderEthernetAddr, arpHeader.senderIPAddr);
adapter.PopulateTxRing(packet, data);
}
else
{
// otherwise we are done
DebugPrint(
"Handling reply ({2},{3}) <--- ({0},{1})\n",
arpHeader.senderIPAddr, arpHeader.senderEthernetAddr,
arpHeader.destIPAddr, arpHeader.destEthernetAddr
);
//delete packet;
}
if (merged && !updated)
{
DebugPrint(arpTable.ToString());
}
}
//This function will format the higher layer packet to
//have to correct ethernet and ip header?
//Routing to multiple cards was broken in the old netstack...
//for now we support a single interface
//ipheader is already written...we just need to write the ethernet header
public static void SendOutgoingPacket(Bytes header,
Bytes buffer,
IPv4 destinationAddress)
{
DebugPrint("IP.SendOutgoingPacket: dst {0}\n", destinationAddress);
RouteEntry e = hostConfiguration.RoutingTable.Lookup(destinationAddress);
if (e == null)
{
//delete header;
//delete buffer;
DebugPrint("Packet dropped -- no route\n");
return;
}
IPv4 ifaddr = e.InterfaceAddress;
IPv4 nextHop;
if (e.Gateway == e.InterfaceAddress)
{
nextHop = destinationAddress;
}
else
{
nextHop = e.Gateway;
}
DebugPrint("Selected destination {0}\n", nextHop);
DebugStub.Assert(e.Gateway == e.InterfaceAddress);
IAdapter adapter = hostConfiguration.Bindings.GetAdapter(ifaddr);
VTable.Assert(adapter != null);
EthernetAddress localMac = adapter.HardwareAddress;
EthernetAddress remoteMac;
IAdapter targetAdapter = hostConfiguration.Bindings.GetAdapter(nextHop);
if (targetAdapter != null)
{
remoteMac = targetAdapter.HardwareAddress;
}
else
{
if (arp.Lookup(nextHop, out remoteMac) == false)
{
DebugStub.WriteLine("Outgoing packet, no ARP Entry for: {0}...about to wait\n",
DebugStub.ArgList(nextHop));
arp.ArpRequest(ifaddr, nextHop, localMac, header, buffer, adapter);
// DebugPrint("ArpRequest complete...sending packet\n");
// bool rc = arp.Lookup(nextHop, out remoteMac);
// DebugStub.Assert(rc == true);
return;
}
}
//Format ethernet header
EthernetHeader.Write(header, localMac, remoteMac, EthernetHeader.PROTOCOL_IP);
//send it!
adapter.PopulateTxRing(header, buffer);
}