/*
* Copyright (c) 2009 Lukas Mejdrech
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup udp
* @{
*/
/** @file
* UDP header definition.
* Based on the RFC~768.
*/
#ifndef __NET_UDP_HEADER_H__
#define __NET_UDP_HEADER_H__
#include <sys/types.h>
/** Type definition of the user datagram header.
* @see udp_header
*/
typedef struct udp_header udp_header_t;
/** Type definition of the user datagram header pointer.
* @see udp_header
*/
typedef udp_header_t * udp_header_ref;
/** User datagram header.
*/
struct udp_header{
/** Source Port is an optional field, when meaningful, it indicates the port of the sending process, and may be assumed to be the port to which a reply should be addressed in the absence of any other information.
* If not used, a value of zero is inserted.
*/
uint16_t source_port;
/** Destination port has a meaning within the context of a particular internet destination address.
*/
uint16_t destination_port;
/** Length is the length in octets of this user datagram including this header and the data.
* This means the minimum value of the length is eight.
*/
uint16_t total_length;
/** Checksum is the 16-bit one's complement of the one's complement sum of a pseudo header of information from the IP header, the UDP header, and the data, padded with zero octets at the end (if necessary) to make a multiple of two octets.
* The pseudo header conceptually prefixed to the UDP header contains the source address, the destination address, the protocol, and the UDP length.
* This information gives protection against misrouted datagrams.
* If the computed checksum is zero, it is transmitted as all ones (the equivalent in one's complement arithmetic).
* An all zero transmitted checksum value means that the transmitter generated no checksum (for debugging or for higher level protocols that don't care).
*/
uint16_t checksum;
} __attribute__ ((packed));
#endif
/** @}
*/