/* 
mask.d
written by, Sohail Qayum Malik<sohail@stupidcomputing.com>.
I don't use D, it is good language. Some day in the near future I'll find some time to seriously do some good learning of this language
*/


import std.c.time;
import std.c.stdio;
import std.socket;

int main(char[][] args){
 
   AddressFamily af;
   SocketType st;
   ProtocolType pt;
   SocketFlags sf;


   int a; 

   int ticksOne = 0;
   int ticksTwo = 0;

    if(args.length != 2){
      printf("%s <IP-address>\n", &(args[0][0]));
      return 0;
   }  
   
   InternetAddress toObj = new InternetAddress(args[1], InternetAddress.PORT_ANY);
   Address fromObj       = new InternetAddress(InternetAddress.ADDR_ANY, InternetAddress.PORT_ANY);
     
   char[512] outBuf;
   char[512] inBuf;  

/*
ICMP header
Big-Endian is used to store multibyte numbers,
Where the bits in a byte follow Little-Endian. 
*/
   outBuf[0] = 0x11; //type
   outBuf[1] = 0x00; //code
   outBuf[2] = 0xEE; //checksum high byte
   outBuf[3] = 0xFd; //checksum low byte 
   outBuf[4] = 0x00; //identifier high byte
   outBuf[5] = 0x01; //identifier low byte
   outBuf[6] = 0x00; //sequence number high byte
   outBuf[7] = 0x01; //sequence number low byte


   Socket socketObj = new Socket(af.INET, st.RAW, pt.ICMP);

   socketObj.blocking = true; 

   socketObj.sendTo(outBuf, toObj);

   ticksOne = clock();

   printf("pinged....\n\n"); 
  
   socketObj.receiveFrom(inBuf, fromObj );

   ticksTwo = clock(); 

   char[] ip = (cast(InternetAddress)fromObj).toAddrString();

   printf("echo from %s:\n", &(ip[0]) ); 
   printf("IP header....\n");
   printf("Version and HeaderLegth = %.2xh ", inBuf[0]);
   printf("TOS = %.2xh ", inBuf[1]);  
   printf("Total length = %.2x%.2xh ", inBuf[2], inBuf[3]);
   printf("Identifier = %.2x%.2xh ", inBuf[4], inBuf[5]); 
   printf("Flag and SequenceNumber = %.2x%.2x ", inBuf[6], inBuf[7]);
   printf("TTL = %.2x ", inBuf[8]);
   printf("Protocol Type = %.2x ", inBuf[9]);
   printf("Checksum = %.2x%.2x ", inBuf[10], inBuf[11]); 
   printf("SourceIP = %.2d.%.2d.%.2d.%.2d ",inBuf[12], inBuf[13], inBuf[14],inBuf[15]);
   printf("DestinationIP = %.2d.%.2d.%.2d.%.2d\n",inBuf[16], inBuf[17], inBuf[18],inBuf[19]);

   printf("ICMP payload....\n");
   printf("Type = %.2xh ", inBuf[20]);
   printf("Code = %.2xh ", inBuf[21]);
   printf("Checksum = %.2x%.2xh ", inBuf[22], inBuf[23]);
   printf("Identifier = %.2x%.2xh ", inBuf[24], inBuf[25]);
   printf("Sequence Number=%.2x%.2xh\n", inBuf[26], inBuf[27]);
   
   printf("mask = %d.%d.%d.%d\n", inBuf[28], inBuf[29], inBuf[30], inBuf[31]);
   
   
   printf("message dump:\n");
   for(a=0; a< ((inBuf[2] * 256) + inBuf[3]) - 32;a++)
   printf("%.2x ",inBuf[32 + a]);    


   printf("\nTime taken(in mili-seconds) = %d", (ticksTwo - ticksOne) / CLK_TCK);

             
   return 0;

}