/*
	Packet.h
	Copyright (C) 2003 Mike Saywell
	
	Southampton Open Wireless Network,
	http://www.sown.org.uk
	
	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License
	as published by the Free Software Foundation; either version 2
	of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.
	
	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. 

*/

#include <sys/types.h>
#include <sys/socket.h>
#include <netpacket/packet.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/udp.h>
#include <net/ethernet.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <linux/sockios.h>
#include <sys/ioctl.h>
#include <string.h>
#include <iostream>
#include <errno.h>
#include <unistd.h>
#include <sys/socket.h>

#include "AddressManager.h"

using namespace std;

/* Aladin protocol layout

             (bits)
0.......8......16......24......32
---------------------------------
| Type  |       Reserved        |
+-------------------------------+ _
|            Network            |  \ 
|            Netmask            |   > Used by ALADIN_REPLY
--------------------------------- _/

Every aladin message is one of the following basic types, this in itself
is sufficient except for the REPLY case where an IP and netmask need to
be communicated.

	*** Types ***		*/
static u_char ALADIN_INVALID = 0;
static u_char ALADIN_HELLO = 1;
static u_char ALADIN_REQUEST = 2;
static u_char ALADIN_REPLY = 3;
static u_char ALADIN_ACK = 4;

// Ethertype reserved to DEC but unassigned, hopefully they wont mind :)
// Tried using one from the experimental range but got mixed results, bug??
static uint16_t ALADIN_PROTOCOL = 0x8039;

static size_t ALADIN_LEN=50;

class Packet {
	private:
		u_char type;
		struct sockaddr dst;
		u_int32_t network;
		u_int32_t netmask;
	public:
		Packet(u_char t);

		u_char getType();
		void setType(u_char t);
		int genPkt(u_char* msg);
		void prnType(char* type);
		void reset();
		void setNetwork(struct in_addr* net);
		void setNetmask(struct in_addr* mask);

		u_int32_t getNetwork();
		u_int32_t getNetmask();

		static int send(Packet* p, int if_id);
		static int receive(Packet* p, int if_id, int timeout);
		static int parse(u_char* raw, Packet* p);
};