/// <summary>
/// This method takes the "hostname" of the server
/// and then it ping's it and shows the response time
/// </summary>
public static bool PingHost(string clientAddress)
{
//Declare the IPHostEntry
IPEndPoint ipepServer, ipepLocal;
int nBytes = 0;
long dwStart = 0;
LogFile.Network("Ping Address: " + clientAddress);
try
{
//Initilize a Socket of the Type ICMP
using (Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.Icmp))
{
// Get the server endpoint
ipepServer = new IPEndPoint(IPAddress.Parse(Microsoft.SPOT.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces()[0].GatewayAddress), 0);
EndPoint epServer = (ipepServer);
// Set the receiving endpoint to the client machine
ipepLocal = new IPEndPoint(IPAddress.Parse(Microsoft.SPOT.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces()[0].IPAddress), 0);
EndPoint epLocal = (ipepLocal);
int PacketSize = 0;
IcmpPacket packet = new IcmpPacket();
// Construct the packet to send
packet.Type = ICMP_ECHO; //8
packet.SubCode = 0;
packet.CheckSum = UInt16.Parse("0");
packet.Identifier = UInt16.Parse("45");
packet.SequenceNumber = UInt16.Parse("0");
int PingData = 32; // sizeof(IcmpPacket) – 8;
packet.Data = new Byte[PingData];
//Initilize the Packet.Data
for (int i = 0; i < PingData; i++)
{
packet.Data[i] = (byte)'#';
}
//Variable to hold the total Packet size
PacketSize = PingData + 8;
Byte[] icmp_pkt_buffer = new Byte[PacketSize];
Int32 Index = 0;
//Call a Method Serialize which counts
//The total number of Bytes in the Packet
Index = Serialize(
packet,
icmp_pkt_buffer,
PacketSize,
PingData);
//Error in Packet Size
if (Index == -1)
{
return false;
}
// now get this critter into a UInt16 array
//Get the Half size of the Packet
Double double_length = (double)Index;
Double dtemp = System.Math.Ceiling(double_length / 2);
int cksum_buffer_length = (int)dtemp;
//Create a Byte Array
UInt16[] cksum_buffer = new UInt16[cksum_buffer_length];
//Code to initialize the Uint16 array
int icmp_header_buffer_index = 0;
for (int i = 0; i < cksum_buffer_length; i++)
{
cksum_buffer[i] =
BitConverter.ToUInt16(icmp_pkt_buffer, icmp_header_buffer_index);
icmp_header_buffer_index += 2;
}
//Call a method which will return a checksum
UInt16 u_cksum = checksum(cksum_buffer, cksum_buffer_length);
//Save the checksum to the Packet
packet.CheckSum = u_cksum;
// Now that we have the checksum, serialize the packet again
Byte[] sendbuf = new Byte[PacketSize];
//again check the packet size
Index = Serialize(packet, sendbuf, PacketSize, PingData);
//if there is a error report it
if (Index == -1)
{
return false;
}
dwStart = DateTime.Now.Ticks; // Start timing and send the Pack over the socket
socket.SendTimeout = 5000;
if ((nBytes = socket.SendTo(sendbuf, PacketSize, 0, epServer)) == SOCKET_ERROR)
{
return false;
}
// Initialize the buffers. The receive buffer is the size of the
// ICMP header plus the IP header (20 bytes)
Byte[] ReceiveBuffer = new Byte[256];
nBytes = 0;
long timeout = 0;
socket.ReceiveTimeout = 5000;
while (true)
{
nBytes = socket.ReceiveFrom(ReceiveBuffer, 256, 0, ref epLocal);
if (nBytes == SOCKET_ERROR)
{
return false;
}
else if (nBytes > 0)
{
return true;
}
timeout = DateTime.Now.Ticks - dwStart;
if (timeout > 1000)
{
return false;
}
}
}
}
catch (Exception)
{
return false;
}
}
/// <summary>
/// This method get the Packet and calculates the total size
/// of the Pack by converting it to byte array
/// </summary>
public static Int32 Serialize(IcmpPacket packet, Byte[] Buffer,
Int32 PacketSize, Int32 PingData)
{
Int32 cbReturn = 0;
// serialize the struct into the array
int Index = 0;
Byte[] b_type = new Byte[1];
b_type[0] = (packet.Type);
Byte[] b_code = new Byte[1];
b_code[0] = (packet.SubCode);
Byte[] b_cksum = BitConverter.GetBytes(packet.CheckSum);
Byte[] b_id = BitConverter.GetBytes(packet.Identifier);
Byte[] b_seq = BitConverter.GetBytes(packet.SequenceNumber);
// Console.WriteLine("Serialize type ");
Array.Copy(b_type, 0, Buffer, Index, b_type.Length);
Index += b_type.Length;
// Console.WriteLine("Serialize code ");
Array.Copy(b_code, 0, Buffer, Index, b_code.Length);
Index += b_code.Length;
// Console.WriteLine("Serialize cksum ");
Array.Copy(b_cksum, 0, Buffer, Index, b_cksum.Length);
Index += b_cksum.Length;
// Console.WriteLine("Serialize id ");
Array.Copy(b_id, 0, Buffer, Index, b_id.Length);
Index += b_id.Length;
Array.Copy(b_seq, 0, Buffer, Index, b_seq.Length);
Index += b_seq.Length;
// copy the data
Array.Copy(packet.Data, 0, Buffer, Index, PingData);
Index += PingData;
if (Index != PacketSize/* sizeof(IcmpPacket) */)
{
cbReturn = -1;
return cbReturn;
}
cbReturn = Index;
return cbReturn;
}
