//*****************************************************************************
//
// Program: vsend -- Programming Project 2
//
// Author: Travis Dillon
//
// Class: CS 444
// Email: tdillon@ace.cs.ohiou.edu
//
// Description: This is a program to test the vbridge. This program sends a
// packet to another computer on the virtual lan.
//
// Date: January 14, 2005
//
//*****************************************************************************
#include <stdlib.h>
#include <iostream.h>
#include <vrouter.h>
#include <unistd.h>
#define DEFAULT_GROUP 6
#define BUFFER_SIZE 512
#define INTERFACE_NAME_LENGTH 100
#define DEFAULT_MSECS 1000
using namespace std;
void option_h();
void option_l(lanlist* all_lans, _lan* lan_ptr);
void option_g(int argc, char** argv, unsigned& group, int& i);
void option_i(int argc, char** argv, unsigned& group, int& i,
char*& interface, lanlist* all_lans);
void option_t(int argc, char** argv, int& msecs, int& i);
void option_c(int argc, char** argv, int& count, int& i);
void make_buffer(char** argv, char buf[], lanlist* all_lans, int& i);
typedef struct _Ethernet
{
unsigned char destination[7];
unsigned char source[7];
unsigned char type[3];
}Ethernet;
int main(int argc, char *argv[])
{
int i, packet_size(0), msecs(DEFAULT_MSECS), count(-1);
char buf[BUFFER_SIZE], *interface;
unsigned group = DEFAULT_GROUP;
bool debug_on = false, infinite_loop = true;
lanlist* all_lans = whichlans();
_lan* lan_ptr;
INTERFACE* iface;
if(all_lans == NULL)
{
cout << "whichlans() failed and returned NULL\n";
exit(EXIT_FAILURE);
}
lan_ptr = all_lans -> lan;
interface = lan_ptr -> lname;
for(i=1; i < argc - 1; ++i) //parse the command line
{
if(argv[i][0] != '-') //at this point an argument must have a '-'
{
cout << "Invalid option - \"" << argv[i] << "\".\n";
option_h();
}
switch(argv[i][1])
{
case 'd': debug_on = true; break;
case 'l': option_l(all_lans, lan_ptr); break;
case 'g': option_g(argc, argv, group, i); break;
case 'i': option_i(argc, argv, group, i, interface, all_lans); break;
case 't': option_t(argc, argv, msecs, i); break;
case 'c': option_c(argc, argv, count, i); break;
case 'h': option_h(); break;
default:
{
cout << "Invalid option - \"" << argv[i] << "\".\n";
option_h();
break;
}
}
}
make_buffer(argv, buf, all_lans, i);
if(debug_on)
{
cout << "interface = " << interface << "\ngroup = " << group
<< "\nmsecs = " << msecs << "\ncount = " << count << endl << endl;
}
iface = openinterface(interface, group);
if(iface == NULL)
{
cout << "openinterface failed.\n";
exit(EXIT_FAILURE);
}
if(count > 0) infinite_loop = false;
while(count > 0 || infinite_loop) //send packets
{
packet_size = writepacket(iface, buf, 101);
if(packet_size < 0)
{
cout << "\nERROR in writepacket.\n";
exit(EXIT_FAILURE);
}
usleep(msecs); //wait to send next packet
--count;
}
closeinterface(iface);
exit(EXIT_SUCCESS);
}
//****************************************************************************
//
// Function: option_h
//
// Purpose: If the -h flag is given in the command line or someone enters
// an invalid command argument, this will print out options.
//
// Parameters: none
//
// Calls: exit
//
//****************************************************************************
void option_h()
{
cout << "-d To print debugging information.\n"
<< "-l List all interfaces and exit.\n"
<< "-g NUM Use group NUM. If NUM is ommitted then " << DEFAULT_GROUP
<< " will be used.\n"
<< "-i IFACE Use interface IFACE. Use first interface"
<< " if IFACE is ommitted.\n"
<< "-t MSECS Send packet every MSECS milliseconds, " << DEFAULT_MSECS
<< " by default.\n"
<< "-c COUNT Send COUNT packets or infinitely many for default.\n"
<< "-h Print a quick summary of the command line arguments"
<< " and exit.\n";
exit(EXIT_SUCCESS);
}
//****************************************************************************
//
// Function: option_l
//
// Purpose: If the -l flag is given in the command line this will print
// all the names and addresses of network devices on a computer.
//
// Parameters: all_lans - linked list that holds all network addresses and
// names of them on the computer
// lan_ptr - pointer to the head of the linked list
//
// Calls: exit
//
//****************************************************************************
void option_l(lanlist* all_lans, _lan* lan_ptr)
{
for(int j(0); j < all_lans -> cnt; ++j)
{
cout << "name = " << lan_ptr -> lname << endl;
cout << "addr = " << lan_ptr -> hwaddr << endl << endl;
lan_ptr = lan_ptr -> next;
}
exit(EXIT_SUCCESS);
}
//****************************************************************************
//
// Function: option_g
//
// Purpose: If the -g NUM flag is given in the command line this will
// change the group to NUM as long as NUM is in [0, 63]
//
// Parameters: argc - number of command line arguments
// argv - the commmand line arguments
// i - position in the command line arguments
//
// Calls: none
//
//****************************************************************************
void option_g(int argc, char** argv, unsigned& group, int& i)
{
if(i < argc - 2 && argv[i + 1][0] != char(45))
{ //true if -g isn't last command and -g has numbers after it
group = argv[++i][0] - 48; //ascii for zero is 48
if(argv[i][1] != '\0') //true if the group is greater than ten
{
group = (group * 10) + (argv[i][1] - 48);
if(argv[i][2] != '\0') //true if the group is greater than 99
{
cout << "INVALID group number. Defaulting to "
<< DEFAULT_GROUP << ".\n";
group = DEFAULT_GROUP;
}
}
}
if(group > 63) //valid range of group numbers is 0 - 63
{
cout << "INVALID group number. Defaulting to " << DEFAULT_GROUP << ".\n";
group = DEFAULT_GROUP;
}
}
//****************************************************************************
//
// Function: option_i
//
// Purpose: If the -i IFACE flag is given in the command line this will
// change the interface name to IFACE if it is valid.
//
// Parameters: argc - number of command line arguments
// argv - the commmand line arguments
// group - the group the packets are sent to
// i - position in the command line arguments
// interface - the name of the interface being used
// all_lans - linked list that holds all network addresses and
// names of them on the computer
//
// Calls: strncmp
//
//****************************************************************************
void option_i(int argc, char** argv, unsigned& group, int& i,
char*& interface, lanlist* all_lans)
{
_lan* temp_lan_ptr = all_lans -> lan;
bool good_iface_name = false;
if(i < argc - 2 && argv[i + 1][0] != char(45)) //check if next arg starts
{ //with a '-'
++i;
for(int j(0); j < all_lans -> cnt; ++j)
{
if(strncmp(temp_lan_ptr -> lname, argv[i], INTERFACE_NAME_LENGTH) == 0)
{ //the given arguemnt to -i is a good one.
good_iface_name = true;
}
temp_lan_ptr = temp_lan_ptr -> next;
}
if(good_iface_name)
{ //the given IFACE is a valid one, let's use it.
interface = argv[i];
}
else
{ //the given argument to -i was invalid so we'll use the first one
cout << "INVALID interface name. Defaulting to " << interface << endl;
}
}
}
//****************************************************************************
//
// Function: option_t
//
// Purpose: If the -t MSECS flag is given in the command line this will
// change the delay between the time packets are sent. 1000 default.
//
// Parameters: argc - number of command line arguments
// argv - the commmand line arguments
// msecs - number of milliseconds of delay
// i - position in the command line arguments
//
// Calls: none
//
//****************************************************************************
void option_t(int argc, char** argv, int& msecs, int& i)
{
if(i < argc - 2 && argv[i + 1][0] != char(45))
{
++i;
for(size_t j(0); argv[i][j] != '\0'; ++j)
{
msecs = ((j == 0) ? (argv[i][j] - 48) : (msecs*10 + argv[i][j] - 48));
}
}
}
//****************************************************************************
//
// Function: option_c
//
// Purpose: If the -c NUM flag is given in the command line this will
// change the number of packets that are sent. Infinite is default.
//
// Parameters: argc - number of command line arguments
// argv - the commmand line arguments
// count - number of packets sent
// i - position in the command line arguments
//
// Calls: none
//
//****************************************************************************
void option_c(int argc, char** argv, int& count, int& i)
{
if(i < argc - 2 && argv[i + 1][0] != char(45))
{
++i;
for(size_t j(0); argv[i][j] != '\0'; ++j)
{
count = ((j == 0) ? (argv[i][j] - 48) : (count*10 + argv[i][j] - 48));
}
}
}
//****************************************************************************
//
// Function: make_buffer
//
// Purpose: To make a packet.
//
// Parameters: argv - the commmand line arguments
// buf - holds the data
// all_lans - linked list that holds all network addresses and
// names of them on the computer
// i - position in the command line arguments
//
// Calls: none
//
//****************************************************************************
void make_buffer(char** argv, char buf[], lanlist* all_lans, int& i)
{
size_t g = 0;
int tens, ones, hex_to_dec(1);
for(size_t w(0); w < 17; ++w)
{ //this creates the destination, first 6 octets of buffer
tens = argv[i][w];
ones = argv[i][w + 1];
tens = ((tens > 57) ? (tens -= 87) : (tens -= 48));
ones = ((ones > 57) ? (ones -= 87) : (ones -= 48));
hex_to_dec = 16 * tens + ones;
buf[g++] = hex_to_dec;
w += 2;
}
for(size_t w(0); all_lans -> lan -> hwaddr[w] != '\0'; ++w)
{ //this creates the destination, next 6 octets of buffer
tens = all_lans -> lan -> hwaddr[w];
ones = all_lans -> lan -> hwaddr[w + 1];
tens = ((tens > 57) ? (tens -= 87) : (tens -= 48));
ones = ((ones > 57) ? (ones -= 87) : (ones -= 48));
hex_to_dec = 16 * tens + ones;
buf[g++] = hex_to_dec;
w += 2;
}
//this creates the type, next two octets of buffer
buf[g++] = 0;
buf[g++] = 0;
for(; g < 100; ++g)
{ //this creates some junk data for the rest of the buffer
buf[g] = g + 20;
}
buf[g] = '\0';
}