private static void SendMDNSNameReply()
{
if (Adapter.IPAddress == null || Networking.Adapter.Name == string.Empty)
{
return;
}
prefix.Overwrite(0, new byte[6] {
0x01, 0x00, 0x5e, 0x00, 0x00, 0xfb
});
prefix.Overwrite(6, Adapter.MacAddress); // Source MAC Address
prefix.Overwrite(26, Adapter.IPAddress); // Source IP Address
lock (lockObj)
{
// Set the all-important name and IP address -- that's the whole purpose here...!
suffix.Overwrite(10, Adapter.IPAddress);
var result = Utility.CombineArrays(prefix, Utility.CombineArrays(DNS.EncodeDnsName(Networking.Adapter.Name + ".local"), suffix));
result.Overwrite(16, ((ushort)(result.Length - 14)).ToBytes()); // Set IPv4 message size
result.Overwrite(38, ((ushort)(result.Length - 34)).ToBytes()); // Set UDP message size
result.Overwrite(24, new byte[] { 0x00, 0x00 }); // clear header checksum, so that calc excludes the checksum itself
result.Overwrite(24, result.InternetChecksum(20, 14)); // header checksum
result.Overwrite(40, new byte[] { 0x00, 0x00 }); // clear UDP Checksum
Debug.WriteLine("Sending MDNS name message! ");
Adapter.nic.SendFrame(result); // Send the packet out into the ether....!
}
}
/// <summary>
///
/// </summary>
private static void SendLLMNRNameReply(string name, byte[] tranID, byte[] destinationMac, byte[] destinationIP, byte[] destinationPort)
{
if (Adapter.IPAddress == null || Networking.Adapter.Name == string.Empty)
{
return;
}
lock (lockObj)
{
prefix.Overwrite(0, destinationMac);
prefix.Overwrite(6, Adapter.MacAddress); // Source MAC Address
prefix.Overwrite(26, Adapter.IPAddress); // Source IP Address
prefix.Overwrite(30, destinationIP);
prefix.Overwrite(36, destinationPort);
prefix.Overwrite(42, tranID);
var suffix = new byte[name.Length * 2 + 22];
var byteName = Utility.CombineArrays(DNS.EncodeDnsName(name), new byte[4] {
0x00, 0x01, 0x00, 0x01
});
suffix.Overwrite(0, Utility.CombineArrays(byteName, byteName));
suffix.Overwrite(suffix.Length - 7, new byte[1] {
0x1e
}); // Time To Live (30 seconds)
suffix.Overwrite(suffix.Length - 5, new byte[1] {
0x04
}); // IP Address length
suffix.Overwrite(suffix.Length - 4, Adapter.IPAddress);
var result = Utility.CombineArrays(prefix, suffix);
result.Overwrite(16, ((ushort)(result.Length - 14)).ToBytes()); // Set IPv4 message size
result.Overwrite(38, ((ushort)(result.Length - 34)).ToBytes()); // Set UDP message size
result.Overwrite(24, new byte[] { 0x00, 0x00 }); // clear header checksum, so that calc excludes the checksum itself
result.Overwrite(24, result.InternetChecksum(20, 14)); // header checksum
result.Overwrite(40, new byte[] { 0x00, 0x00 }); // clear UDP Checksum
Adapter.nic.SendFrame(result); // Send the packet out into the ether....!
Debug.WriteLine("LLMNR Response sent");
}
}
/// <summary>
/// Seperate send method to share a lock so that we don't mix up packets...
/// </summary>
/// <param name="packetType"></param>
internal static void SendMessage(byte[] packetType)
{
lock (MagicCookie)
{
scratch.Overwrite(0, Adapter.BroadcastMAC); // Destination MAC Address
scratch.Overwrite(6, Adapter.MacAddress); // Source MAC Address
scratch.Overwrite(30, Adapter.BroadcastIPAddress); // Destiantion IP Address
scratch.Overwrite(54, Adapter.BlankIPAddress); // Source IP Address
scratch.Overwrite(70, Adapter.MacAddress); // Source MAC Address Again inside the DHCP section
scratch.Overwrite(284, packetType);
byte[] options = new byte[13 + (Adapter.Name == string.Empty ? 0 : Adapter.Name.Length + 2)];
options.Overwrite(0, Adapter.MacAddress);
transactionID = transactionID ?? Extensions.GetRandomBytes(4); // Make up some transaction ID
if (packetType == DHCP.Discover)
{
// Debug.WriteLine("Composing Discover Message");
PendingIpAddress = null;
//scratch.Overwrite(306, suffix); // write the Discover suffix
options.Overwrite(6, new byte[6] {
0x33, 0x04, 0x00, 0x76, 0xa7, 0x00
}); // Request an IP lease time of 90 days
}
else if (packetType == DHCP.Request && PendingIpAddress != null && Adapter.Gateway != null)
{
//Debug.WriteLine("Composing Request Message");
options.Overwrite(6, new byte[2] {
0x32, 0x04
}); // Set the option prefix for IP Address
options.Overwrite(8, PendingIpAddress); // Set the option Value
options.Overwrite(12, new byte[2] {
0x36, 0x04
}); // Set the option prefix for Gateway
options.Overwrite(14, Adapter.Gateway); // Set the option value
if (Adapter.GatewayMac != null && Adapter.Gateway != null && Adapter.IPAddress != null)
{
// This is for the renewals
//TODO: Test to make sure this works!
//scratch.Overwrite(0, Adapter.GatewayMac);
//scratch.Overwrite(30, Adapter.Gateway);
scratch.Overwrite(54, Adapter.IPAddress);
}
}
else
{
Debug.WriteLine("Odd DHCP situation... should we be concerned?");
return;
}
if (Adapter.Name != string.Empty)
{
// Add Hostname option to Discover and Request messages
options.Overwrite(options.Length - (Adapter.Name.Length + 3), new byte[1] {
0x0c
});
options.Overwrite(options.Length - (Adapter.Name.Length + 2), DNS.EncodeDnsName(Adapter.Name));
}
options.Overwrite(options.Length - 1, new byte[1] {
0xFF
}); // End of option section marker
scratch.Overwrite(46, transactionID); // Write the transaction ID
var result = Utility.CombineArrays(scratch, options);
result.Overwrite(16, ((ushort)(result.Length - 14)).ToBytes()); // Set IPv4 message size
result.Overwrite(38, ((ushort)(result.Length - 34)).ToBytes()); // Set UDP message size
result.Overwrite(24, new byte[] { 0x00, 0x00 }); // clear header checksum, so that calc excludes the checksum itself
result.Overwrite(24, result.InternetChecksum(20, 14)); // header checksum
result.Overwrite(40, new byte[] { 0x00, 0x00 }); // clear UDP Checksum
Adapter.nic.SendFrame(result); // Send the packet out into the ether....!
}
}
