/*
 * multicast.h
 *
 *  Created on: 05.07.2010
 *      Author: schalli
 */

#ifndef __TINC_MULTICAST_H__
#define __TINC_MULTICAST_H__

#include "system.h"

#include "logger.h"
#include "net.h"
#include "utils.h"

#ifdef HAVE_MINGW
#include <iphlpapi.h>

// Set the flags to pass to GetAdaptersAddresses
extern const ULONG flags;
#endif

// Multicast TTL is 1, since we announce to local network
extern const int multicastTTL;

// Multicast port is 16655 for every network
extern const int multicastPort;

/* IPv4 Multicast address */
extern struct sockaddr_in multicastAddr4;

/* IPv6 Multicast address */
extern struct sockaddr_in6 multicastAddr6;

/** keeps all multicast sockets */
extern listen_socket_t multicast_socket[MAXSOCKETS];
extern int multicast_sockets;

/** The challenge we sent */
#define MC_CHALLENGE_SIZE 128
extern char mc_challenge[];
extern struct timeval mc_timestamp;

#define STRLEN 64

typedef enum mcpacket_type_t {
	MCPKT_ANNOUNCE, /* Multicast announce */
	MCPKT_RESPONSE
/* Multicast response to announce */
} mcpacket_type_t;

typedef struct mcpacket_announce_t {
} mcpacket_announce_t;

typedef struct mcpacket_response_t {
	u_short port;
	char signature[EVP_MAX_MD_SIZE];
} mcpacket_response_t;

typedef struct mcpacket_t {
	mcpacket_type_t type;
	char netname[STRLEN];
	char hostname[STRLEN];
	char challenge[MC_CHALLENGE_SIZE];
	union {
		mcpacket_announce_t announce;
		mcpacket_response_t response;
	};
} mcpacket_t;

extern mcpacket_t *new_mcpacket(void) __attribute__ ((__malloc__));
extern void free_mcpacket(mcpacket_t *);
extern int check_signature(const node_t *, mcpacket_t *);
extern void set_signature(const node_t *, mcpacket_t *);

extern void init_multicast(void);

extern void handle_multicast_data(int);
extern void receive_multicast_packet(int, mcpacket_t *, union sockaddr_t *);

extern void send_multicast_announces(void);
extern void send_multicast_announce(const mcpacket_t *, const int socketIdx);
extern void receive_multicast_announce(const int, const  mcpacket_t *, const node_t *, const sockaddr_t *);
extern void send_multicast_response(const int, const mcpacket_t *, const node_t *, const sockaddr_t *);
extern void receive_multicast_response(node_t *, const sockaddr_t *, const mcpacket_t *);

extern void bind_multicast_sockets(void);
extern void bind_multicast_socket(sockaddr_t *, int);
extern void close_multicast_sockets(void);
extern void close_multicast_socket(const int);

#endif /* __TINC_MULTICAST_H__ */