Namespace saurabhping
{
Using system;
Using system. net;
Using system. net. Sockets;
/// <Summary>
/// The main Ping class
/// </Summary>
Class Ping
{
// Declare some constant variables
Const int socket_error =-1;
Const int ICMP_Echo = 8;
/// <Summary>
/// The starting point of the class
/// It takes the hostname Parameter
/// </Summary>
Public static void main (string [] argv)
{
If (argv. Length = 0)
{
// If user did not enter any parameter inform him
Console. writeline ("Usage: Ping Console. writeline ("Console. writeline ("/R ping the host continuously ");
}
Else if (argv. Length = 1)
{
// Just the hostname provided by the user
// Call the method "pinghost" and pass the hostname as a parameter
Pinghost (argv [0]);
}
Else if (argv. Length = 2)
{
// The user provided the hostname and the switch
If (argv [1] = "/R ")
{
// Loop the Ping program
While (true)
{
// Call the method "pinghost" and pass the hostname as a parameter
Pinghost (argv [0]);
}
}
Else
{
// If the user provided some other switch
Pinghost (argv [0]);
}
}
Else
{
// Some error occurred
Console. writeline ("error in arguments ");
}
}/// <Summary>
/// This method takes the "hostname" of the server
/// And then it Ping's IT and shows the response time
/// </Summary>
Public static void pinghost (string host)
{
// Declare the iphostentry
Iphostentry serverhe, fromhe;
Int nbytes = 0;
Int dwstart = 0, dwstop = 0;
// Initilize a socket of the type ICMP
Socket socket =
New socket (addressfamily. afinet, sockettype. sockraw, protocoltype. proticmp ); // Get the server endpoint
Try
{
Serverhe = DNS. gethostbyname (host );
}
Catch (exception)
{
Console. writeline ("Host Not Found"); // fail
Return;
} // Convert the server ip_endpoint to an endpoint
Ipendpoint ipepserver = new ipendpoint (serverhe. Addresslist [0], 0 );
Endpoint epserver = (ipepserver ); // Set the processing ing endpoint to the client machine
Fromhe = DNS. gethostbyname (DNS. gethostname ());
Ipendpoint ipendpointfrom = new ipendpoint (fromhe. Addresslist [0], 0 );
Endpoint endpointfrom = (ipendpointfrom ); 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)
{
Console. writeline ("error in making packet ");
Return;
} // Now get this critter into a uint16 Array
Double double_length = convert. todouble (INDEX );
Double dtemp = math. Ceil (double_length/2 );
Int cksum_buffer_length = convert. toint32 (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; // Get the half size of the packet // 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)
{
Console. writeline ("error in making packet ");
Return;
} Dwstart = system. environment. tickcount; // start timing
// Send the pack over the socket
If (nbytes = socket. sendto (sendbuf, packetsize, 0, epserver) = socket_error)
{
Console. writeline ("socket error cannot send packet ");
}
// Initialize the buffers. The receive buffer is the size of
// ICMP header plus the IP header (20 bytes)
Byte [] receivebuffer = new byte [1, 256];
Nbytes = 0;
// Receive the bytes
Bool recd = false;
Int timeout = 0; // Loop for checking the time of the server responding
While (! Recd)
{
Nbytes = socket. Receive
From (receivebuffer, 256, 0, ref endpointfrom );
If (nbytes = socket_error)
{
Console. writeline ("Host Not responding ");
Recd = true;
Break;
}
Else if (nbytes> 0)
{
Dwstop = system. environment. tickcount-dwstart; // stop timing
Console. writeline ("reply from" + epserver. tostring () + "in"
+ Dwstop + "MS: bytes received" + nbytes );
Recd = true;
Break;
}
Timeout = system. environment. tickcount-dwstart;
If (timeout> 1000)
{
Console. writeline ("time out ");
Recd = true;
}
} // Close the socket
Socket. Close ();
}
/// <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;
}
/// <Summary>
/// This method has the algorithm to make a checksum
/// </Summary>
Public static uint16 checksum (uint16 [] buffer, int size)
{
Int32 cksum = 0;
Int counter;
Counter = 0; While (size> 0 ){
Uint16 val = buffer [Counter]; Cksum + = convert. toint32 (buffer [Counter]);
Counter + = 1;
Size-= 1;
} Cksum = (cksum> 16) + (cksum & 0 xFFFF );
Cksum + = (cksum> 16 );
Return (uint16 )(~ Cksum );
}
} // Class ping
/// <Summary>
/// Class that holds the Pack information
/// </Summary>
Public class icmppacket
{
Public byte type; // type of message
Public byte subcode; // type of sub code
Public uint16 checksum; // ones complement checksum of struct
Public uint16 identifier; // identifier
Public uint16 sequencenumber; // sequence number
Public byte [] data; } // Class icmppacket
} |
