FTPclient.cpp

/*
 * FTPclient.cpp
 *
 *  Created on: Mar 4, 2016
 *      Author: jeremy
 */

#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <istream>
#include <fstream>
#include <stdlib.h>
#include <iostream>
#include <time.h>
#include <strings.h>
#include <sstream>
#include "packet.h"

//This is the line that displays if there are not 2 parameters input.
#define USAGE "Usage:\r\nc [tux machine number]"
#define PORT 10038
#define PAKSIZE 256
#define BUFSIZE 249
#define ACK 0
#define NAK 1
#define FILENAME "Some.txt"

using namespace std;

bool seqNum;

bool isvpack(unsigned char * p) {


  cout << endl << "=== IS VALID PACKET TESTING" << endl;

  char * sns = new char[2];
  memcpy(sns, &p[0], 1);
  sns[1] = '\0';

  char * css = new char[6];
  memcpy(css, &p[1], 6);
  css[5] = '\0';

  char * db = new char[249 + 1];
  memcpy(db, &p[7], 249);
  db[249] = '\0';

  cout << "Seq. num: " << sns << endl;
  cout << "Checksum: " << css << endl;
  cout << "Message: " << db << endl;

  int sn = atoi(sns);
  int cs = atoi(css);

  Packet pk;
  createPacket(0, db, &pk);
  setSeqNum(sn, &pk);

  if(sn != seqNum) return false;
  if(cs != generateCkSum(pk)) return false;
  return true;
}

int main(int argc, char** argv) {


    struct sockaddr_in server;
    struct sockaddr_in client;
    socklen_t calen = sizeof(server);


    int rlen;
    int s;
    bool ack;
    seqNum = true;

  //If there correct amount of arguement are not input, the method will end.
  if(argc != 2) {
      cout << USAGE << endl;
      return 1;
  }

  //Uses the param (tux number) to append to the known ip of Auburn machine.
  string hs = string("131.204.14.") + argv[1];

  /* Create our socket. */
  if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
    cout << "Socket creation failed. (socket s)" << endl;
    return 0;
  }

  /*
   * Bind our socket to an IP (whatever the computer decides)
   * and a specified port.
   *
   */

  memset((char *)&client, 0, sizeof(client));
  client.sin_family = AF_INET;
  client.sin_addr.s_addr = htonl(INADDR_ANY);
  client.sin_port = htons(PORT);

  if (bind(s, (struct sockaddr *)&client, sizeof(client)) < 0) {
    cout << "Socket binding failed. (socket s, address a)" << endl;
    return 0;
  }

  //Initialize the client information. the sin_addr is set from the hs string up to along with the
  //tux machine number input in the first parameter.
  memset((char *)&server, 0, sizeof(server));
  server.sin_family = AF_INET;
  server.sin_port = htons(PORT);
  inet_pton(AF_INET, hs.c_str(), &(server.sin_addr));

  cout << endl;

  //Prints the address of the machine it wants to send it to.
      cout << "Server address (inet mode): " << inet_ntoa(server.sin_addr) << endl;
      cout << "Port: " << ntohs(server.sin_port) << endl;

      cout << endl << endl;

  ofstream file("Dumpfile2.txt");

  char filename[] = FILENAME;

  cout << endl << "Filename sent to Server" << filename << endl;
  if(sendto(s, filename, strlen(FILENAME), 0, (struct sockaddr *)&server, sizeof(server)) < 0) {
      cout << "Package sending failed. (socket s, client address client, message m)" << endl;
      return 0;
  }


  bool isSeqNumSet = false;
	for(;;) {
    unsigned char packet[PAKSIZE + 1];
    unsigned char dataPull[PAKSIZE - 7 + 1];
    //Wait for a message from the client to see if the packet was received correctly
    rlen = recvfrom(s, packet, PAKSIZE, 0, (struct sockaddr *)&server, &calen);
    packet[rlen] = '\0';

    if(!isSeqNumSet) {
      isSeqNumSet = true;
      char * str = new char[1];
      memcpy(str, &packet[0], 1);
      seqNum = atoi(str);
    }
    for(int x = 0; x < PAKSIZE - 7; x++) {
      dataPull[x] = packet[x + 7];
    }
    dataPull[PAKSIZE - 7] = '\0';
    packet[PAKSIZE] = '\0';
    if (rlen > 0) {
      char * css = new char[6];
      memcpy(css, &packet[1], 6);
      css[5] = '\0';
      cout << endl << endl << "=== RECEIPT" << endl;
      cout << "Seq. num: " << packet[0] << endl;
      cout << "Checksum: " << css << endl;
      cout << "Received message: " << dataPull << endl;
      cout << "Sent response: ";
      if(isvpack(packet)) {
        ack = ACK;
        if (seqNum) {
            seqNum = false;
        }
        else {
            seqNum = true;
        }
        file << dataPull;
	file.flush();
      } else {
        ack = NAK;
      }
      if (ack == ACK) {
        cout << "ACK" << endl;
      }
      else {
 	      cout << "NAK" << endl;
      }
      Packet p;
      if (seqNum) {
          createPacket(false, reinterpret_cast<const char *>(dataPull), &p);
      } else {
          createPacket(true, reinterpret_cast<const char *>(dataPull), &p);
      }
      setCkSum(atoi(css), &p);
      setAck(ack, &p);
	file.flush();
	
      if(sendto(s, str(p), PAKSIZE, 0, (struct sockaddr *)&server, calen) < 0) {
        cout << "Acknowledgement failed. (socket s, acknowledgement message ack, client address ca, client address length calen)" << endl;
        return 0;
      }
      delete css;
      file.flush();
    }
  
}
file.close();
}