/*
 * Copyright (C) 2006 Tobias Brunner, Daniel Roethlisberger
 * Copyright (C) 2005-2008 Martin Willi
 * Copyright (C) 2005 Jan Hutter
 * Hochschule fuer Technik Rapperswil
 *
 * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
 *
 * 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.
 *
 * $Id: socket.h 4647 2008-11-13 07:48:27Z martin $
 */

/**
 * @defgroup socket socket
 * @{ @ingroup network
 */

#ifndef SOCKET_H_
#define SOCKET_H_

typedef struct socket_t socket_t;

#include <library.h>
#include <network/packet.h>
#include <utils/host.h>
#include <utils/enumerator.h>

/**
 * Maximum size of a packet.
 *
 * 3000 Bytes should be sufficient, see IKEv2 RFC. However, to run our
 * multi-CA test with 2 intermediate CAs, we increase that to 5000 bytes.
 */
#define MAX_PACKET 5000

/**
 * Abstraction of all sockets (IPv4/IPv6 send/receive).
 *
 * All available sockets are bound and the receive function
 * reads from them. There are actually two implementations:
 * The first uses raw sockets to allow binding of other daemons (pluto) to
 * UDP/500. An installed "Linux socket filter" filters out all non-IKEv2 
 * traffic and handles just IKEv2 messages. An other daemon (pluto) must 
 * handle all traffic separately, e.g. ignore IKEv2 traffic, since charon 
 * handles that.
 * The other implementation uses normal sockets and is built if
 * --disable-pluto is given to the configure script.
 */
struct socket_t {
	
	/**
	 * Receive a packet.
	 * 
	 * Reads a packet from the socket and sets source/dest
	 * appropriately.
	 * 
	 * @param packet		pinter gets address from allocated packet_t
	 * @return 				
	 * 						- SUCCESS when packet successfully received
	 * 						- FAILED when unable to receive
	 */
	status_t (*receive) (socket_t *this, packet_t **packet);
	
	/**
	 * Send a packet.
	 * 
	 * Sends a packet to the net using source and destination addresses of
	 * the packet.
	 * 
	 * @param packet		packet_t to send
	 * @return 				
	 * 						- SUCCESS when packet successfully sent
	 * 						- FAILED when unable to send
	 */
	status_t (*send) (socket_t *this, packet_t *packet);
	
	/**
	 * Enumerate all underlying socket file descriptors.
	 * 
	 * @return				enumerator over (int fd, int family, int port)
	 */
	enumerator_t *(*create_enumerator) (socket_t *this);
	
	/**
	 * Destroy socket.
	 */
	void (*destroy) (socket_t *this);
};

/**
 * Create a socket_t, which binds multiple sockets.
 *
 * @return  				socket_t object
 */
socket_t *socket_create();

#endif /*SOCKET_H_ @} */