zephyr/subsys/net/l2/ieee802154/ieee802154_fragment.h

100 lines
2.6 KiB
C

/** @file
@brief 802.15.4 fragment handler
This is not to be included by the application.
*/
/*
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef __NET_IEEE802154_FRAGMENT_H__
#define __NET_IEEE802154_FRAGMENT_H__
#include <misc/slist.h>
#include <zephyr/types.h>
#include <net/net_pkt.h>
#include "ieee802154_frame.h"
#ifdef CONFIG_NET_L2_IEEE802154_FRAGMENT
struct ieee802154_fragment_ctx {
struct net_buf *frag;
u8_t *pos;
u16_t pkt_size;
u16_t processed;
u8_t hdr_diff;
u8_t offset;
};
static inline bool ieee802154_fragment_is_needed(struct net_pkt *pkt,
u8_t ll_hdr_size)
{
return (net_pkt_get_len(pkt) + ll_hdr_size >
IEEE802154_MTU - IEEE802154_MFR_LENGTH);
}
static inline
void ieee802154_fragment_ctx_init(struct ieee802154_fragment_ctx *ctx,
struct net_pkt *pkt, u16_t hdr_diff,
bool iphc)
{
ctx->frag = pkt->frags;
ctx->pos = ctx->frag->data;
ctx->hdr_diff = hdr_diff;
ctx->pkt_size = net_pkt_get_len(pkt) + (iphc ? hdr_diff : -1);
ctx->offset = 0;
ctx->processed = 0;
}
/**
* @brief Fragment IPv6 packet as per RFC 6282
*
* @details After IPv6 compression, transmission of IPv6 over 802.15.4
* needs to be fragmented. Every fragment will have fragmentation header
* data size, data offset, data tag and payload.
*
* @param Pointer to valid fragmentation context
* @param Pointer to valid buffer where to write the fragment
* @param bool true for IPHC compression, false for IPv6 dispatch header
*
* @return True in case of success, false otherwise
*/
void ieee802154_fragment(struct ieee802154_fragment_ctx *ctx,
struct net_buf *frame_buf, bool iphc);
/**
* @brief Reassemble 802.15.4 fragments as per RFC 6282
*
* @details If the data does not fit into single fragment whole IPv6 packet
* comes in number of fragments. This function will reassemble them all as
* per data tag, data offset and data size. First packet is uncompressed
* immediately after reception.
*
* @param Pointer to network fragment, which gets updated to full reassembled
* packet when verdict is NET_CONTINUE
*
* @return NET_CONTINUE reassembly done, pkt is complete
* NET_OK waiting for other fragments,
* NET_DROP invalid fragment.
*/
enum net_verdict ieee802154_reassemble(struct net_pkt *pkt);
#else /* CONFIG_NET_L2_IEEE802154_FRAGMENT */
struct ieee802154_fragment_ctx {
struct net_buf *frag;
};
#define ieee802154_fragment_is_needed(...) false
#define ieee802154_fragment_ctx_init(...)
#define ieee802154_fragment(...)
#endif /* CONFIG_NET_L2_IEEE802154_FRAGMENT */
#endif /* __NET_IEEE802154_FRAGMENT_H__ */