rbuf.h
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/*
* Copyright (C) 2015 Martine Lenders <mlenders@inf.fu-berlin.de>
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup net_gnrc_sixlowpan_frag
* @{
*
* @file
* @internal
* @brief 6LoWPAN reassembly buffer
*
* @author Martine Lenders <mlenders@inf.fu-berlin.de>
*/
#ifndef GNRC_SIXLOWPAN_FRAG_RBUF_H_
#define GNRC_SIXLOWPAN_FRAG_RBUF_H_
#include <inttypes.h>
#include "net/gnrc/netif/hdr.h"
#include "net/gnrc/pkt.h"
#include "net/gnrc/sixlowpan/frag.h"
#ifdef __cplusplus
extern "C" {
#endif
#define RBUF_L2ADDR_MAX_LEN (8U) /**< maximum length for link-layer addresses */
#define RBUF_SIZE (4U) /**< size of the reassembly buffer */
#define RBUF_TIMEOUT (3U * SEC_IN_USEC) /**< timeout for reassembly in microseconds */
/**
* @brief Fragment intervals to identify limits of fragments.
*
* @note Fragments MUST NOT overlap and overlapping fragments are to be
* discarded
*
* @see <a href="https://tools.ietf.org/html/rfc4944#section-5.3">
* RFC 4944, section 5.3
* </a>
*
* @internal
*/
typedef struct rbuf_int {
struct rbuf_int *next; /**< next element in interval list */
uint16_t start; /**< start byte of interval */
uint16_t end; /**< end byte of interval */
} rbuf_int_t;
/**
* @brief An entry in the 6LoWPAN reassembly buffer.
*
* @details A receipient of a fragment SHALL use
*
* 1. the source address,
* 2. the destination address,
* 3. the datagram size (gnrc_pktsnip_t::size of rbuf_t::pkt), and
* 4. the datagram tag
*
* to identify all fragments that belong to the given datagram.
*
* @see <a href="https://tools.ietf.org/html/rfc4944#section-5.3">
* RFC 4944, section 5.3
* </a>
*
* @internal
*/
typedef struct {
rbuf_int_t *ints; /**< intervals of the fragment */
gnrc_pktsnip_t *pkt; /**< the reassembled packet in packet buffer */
uint32_t arrival; /**< time in microseconds of arrival of
* last received fragment */
uint8_t src[RBUF_L2ADDR_MAX_LEN]; /**< source address */
uint8_t dst[RBUF_L2ADDR_MAX_LEN]; /**< destination address */
uint8_t src_len; /**< length of source address */
uint8_t dst_len; /**< length of destination address */
uint16_t tag; /**< the datagram's tag */
uint16_t cur_size; /**< the datagram's current size */
} rbuf_t;
/**
* @brief Adds a new fragment to the reassembly buffer. If the packet is
* complete, dispatch the packet with the transmit information of
* the last fragment.
*
* @param[in] netif_hdr The interface header of the fragment, with
* gnrc_netif_hdr_t::if_pid and its source and
* destination address set.
* @param[in] frag The fragment to add.
* @param[in] frag_size The fragment's size.
* @param[in] offset The fragment's offset.
*
* @internal
*/
void rbuf_add(gnrc_netif_hdr_t *netif_hdr, gnrc_pktsnip_t *frag,
size_t frag_size, size_t offset);
#ifdef __cplusplus
}
#endif
#endif /* GNRC_SIXLOWPAN_FRAG_RBUF_H_ */
/** @} */