msgComponent.cpp

/*
(c) Matthew Slocum 2015

msgComponent.cpp 

msgComponent is resbonaible for sending and revieving messages
    upon creation it spins off a thread to listen for incoming messages.
    the parent process takes input from the user and executes commands or sends messages.

*/

#include <iostream>
#include <stdlib.h>
#include <boost/asio.hpp>
#include <pthread.h>
#include <string>
#include "msgComponent.h"
#include "regComponent.h"
#include "secComponent.h"

using namespace std;
using boost::asio::ip::tcp;

msgComponent::msgComponent() {
    
}

//Code derived from:
// daytime_server.cpp
// ~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2015 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See
// at http://www.boost.org/LICENSE_1_0.txt)

//Function for listener thread
//This fucntion listens for incoming connections, recieves a message, decrypts it and displays it.
void* listen(void *threadid) {
    try
      {
        extern regComponent* reg;
        extern secComponent* sec;
        boost::asio::io_service io_service;
        tcp::endpoint endpoint(tcp::v4(), 6283);
        tcp::acceptor acceptor(io_service, endpoint);
        for (;;)
        {
          tcp::iostream stream;
          boost::system::error_code ec;
          acceptor.accept(*stream.rdbuf(), ec);
          //if the is an incomming connection
          if (!ec)
          {           
            string message = "";
            string line;           
            char c;
            char msg [1034];
            int msg_count=0;            
            //get message
            while(stream.get(c)) {           
                msg[msg_count++]=c;
            }           
            //make holder for plaintext
            char plaintext[msg_count];              
            //decrypt message and store in plaintext
            sec->decrypt(msg, msg_count, reg->key, 20, plaintext);          
            //display plaintext message if it exists
            if(msg_count>0) {
                cout << endl << endl;
                for(int i=0; i<msg_count-10; i++) {
                    cout << plaintext[i];
                }
                cout << endl;                    
            }
            //redraw user input prompt
            cout.clear();cout.flush();    
            cout << endl << "TauNet [TO: " << reg->name_list[reg->dest] << "]> "; cout.clear(); cout.flush();         
          }
        }
        
      }
      //catch any std exceptions
      catch (std::exception& e)
      {
        std::cerr << e.what() << std::endl;        
      }
    pthread_exit(NULL);
}

void msgComponent::run() { 
    //spin off thread for listener
    pthread_t thread;
    int rc;
    rc = pthread_create(&thread, NULL, listen, NULL);
    if (rc){
        cout << "Error:unable to create thread," << rc << endl;
        exit(-1);
    } 
    command="";
    //draw some ui
    draw_header();
    draw_dest();    
    //c&c loop
    while(command!=":q") {        
        //get input
        get_input(); 
        //parse special commands
        //list destinations
        if(command==":dlist") {
            reg->printDest();
        }       
        //set destination
        else if (command.find(":dset")==0) {
            //cout << command.substr(6) << endl;
            int d = atoi((command.substr(6)).c_str());
            d--;
            if(d>=0 && d<reg->dest_count) {
                reg->setDest(d);
                draw_dest();
            } else {
                cout << "Destination out of range." << endl;
            }
        }       
        //else, its a message, send it!
        //CODE derived from daytime_client.cpp (Boost::asio)
        //Copyright (c) 2003-2015 Christopher M. Kohlhoff (chris at kohlhoff dot com)
        //Distributed under the Boost Software License, Version 1.0 at http://www.boost.org/LICENSE_1_0.txt)
        else {
            try {           
                boost::asio::io_service io_service;
                boost::asio::ip::tcp::resolver resolver(io_service);
                boost::asio::ip::tcp::resolver::query query(reg->dest_list[reg->dest], "6283");              
                //attempt to open connection
                tcp::iostream stream(reg->dest_list[reg->dest], "6283");
                if (!stream)
                {
                  std::cout << "Unable to connect: " << stream.error().message() << std::endl;
                }                
                //build message
                string message;
                message = string("version: 0.2\r\n") 
                        + "from: " + reg->username + "\r\n"
                        + "to: " + reg->name_list[reg->dest] + "\r\n"
                        + "\r\n"
                        + command + "\r\n";
                
                //init holder for ciphertext
                char ciphertext [message.length()+10];                
                //encrypt the message
                sec->encrypt(message,reg->key,20, ciphertext);                  
                //send the message
                for(unsigned int i=0; i<message.length()+10; i++) {
                    stream << ciphertext[i];
                }
                //close the connection
                stream.close();
            }
            catch (std::exception& e) {
                std::cout << "Exception: " << e.what() << std::endl;
            }
        }
        
    }
}

//let the msgComponent know about the regComponent
void msgComponent::bind_regComponent(regComponent * in) {
    reg = in;
}

//let the msgComponent know about the secComponent
void msgComponent::bind_secComponent(secComponent * in) {
    sec = in;
}

void msgComponent::draw_header() {
    system("clear");
    cout << "|------------TauNet Messenger------------|" << endl;
    cout << "|  Commands" << endl;
    cout << "|   :q        - quit" << endl;
    cout << "|   :dlist    - list destinations" << endl;
    cout << "|   :dset #   - set destination" << endl; 
    cout << "|------------TauNet Messenger------------|" << endl;
}

void msgComponent::draw_dest() {
    cout << "***     DESTINATION: [" << reg->name_list[reg->dest] << "]" << reg->dest_list[reg->dest] << "     ***" << endl;    
}

void msgComponent::get_input() {
    cout << endl;
    cin.clear();
    cout << "TauNet [TO: " << reg->name_list[reg->dest] << "]> ";
    getline(cin,command);
}

void msgComponent::draw_get_input() {
    cout << "TauNet [TO: " << reg->name_list[reg->dest] << "]> ";
}