private void SendResponsePacket(DhcpFormat dhcp)
{
int packetSize = dhcp.Size + UdpFormat.Size +
IPFormat.Size + EthernetFormat.Size;
byte [] packet = new byte [packetSize];
// Write out DHCP packet
int dhcpSize = dhcp.Size;
int dhcpOffset = packet.Length - dhcpSize;
dhcp.Write(packet, dhcpOffset);
// Create UDP Header
UdpFormat.UdpHeader udpHeader = new UdpFormat.UdpHeader();
udpHeader.srcPort = DhcpFormat.ServerPort;
udpHeader.dstPort = DhcpFormat.ClientPort;
udpHeader.length = (ushort)(UdpFormat.Size + dhcpSize);
// Create IP Header
IPFormat.IPHeader ipHeader = new NetStack.Protocols.IPFormat.IPHeader();
ipHeader.SetDefaults(IPFormat.Protocol.UDP);
IPFormat.SetDontFragBit(ipHeader);
ipHeader.Source = ServerAddress;
ipHeader.Destination = IPv4.Broadcast;
ipHeader.totalLength = (ushort)(IPFormat.Size + UdpFormat.Size + dhcpSize);
// Write out IP and Header
int udpOffset = packet.Length - dhcp.Size - UdpFormat.Size;
int ipOffset = udpOffset - IPFormat.Size;
UdpFormat.WriteUdpPacket(packet, ipOffset,
ref ipHeader, ref udpHeader,
packet, dhcpOffset, dhcpSize);
// Add Ethernet Header
EthernetFormat.Write(packet, 0, ServerMac,
EthernetAddress.Broadcast,
EthernetFormat.Protocol.IP);
NetPacket np = new NetPacket(packet);
if (adapter.ReceivePacket(np) == false)
{
Console.WriteLine("Failed to send packet");
SetState(ServerState.Failed);
}
}
internal bool Send(EthernetAddress dstAddr, DhcpFormat !dhcp)
{
int packetSize = dhcp.Size + UdpFormat.Size +
IPFormat.Size + EthernetFormat.Size;
byte [] packet = new byte [packetSize];
// Write out DHCP packet
int dhcpSize = dhcp.Size;
int dhcpOffset = packet.Length - dhcpSize;
dhcp.Write(packet, dhcpOffset);
// Create UDP Header
UdpFormat.UdpHeader udpHeader = new UdpFormat.UdpHeader();
udpHeader.srcPort = DhcpFormat.ClientPort;
udpHeader.dstPort = DhcpFormat.ServerPort;
udpHeader.length = (ushort)(UdpFormat.Size + dhcpSize);
// Create IP Header
IPFormat.IPHeader ipHeader = new NetStack.Protocols.IPFormat.IPHeader();
ipHeader.SetDefaults(IPFormat.Protocol.UDP);
IPFormat.SetDontFragBit(ipHeader);
ipHeader.Source = IPv4.Any;
ipHeader.Destination = IPv4.Broadcast;
ipHeader.totalLength = (ushort)(IPFormat.Size + UdpFormat.Size + dhcpSize);
// Write out IP and Header
int udpOffset = packet.Length - dhcp.Size - UdpFormat.Size;
int ipOffset = udpOffset - IPFormat.Size;
UdpFormat.WriteUdpPacket(packet, ipOffset,
ipHeader, ref udpHeader,
packet, dhcpOffset, dhcpSize);
// Add Ethernet Header
EthernetFormat.Write(packet, 0, adapter.HardwareAddress,
dstAddr, EthernetFormat.PROTOCOL_IP);
NetPacket np = new NetPacket(packet);
return(udpSession.WritePacket(np));
}
