1 /*
2 * Copyright (c) 2016 Intel Corporation
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 /**
8 * @file
9 * @brief 802.15.4 6LoWPAN fragment handler
10 *
11 * This is not to be included by the application.
12 */
13
14 #ifndef __NET_IEEE802154_6LO_FRAGMENT_H__
15 #define __NET_IEEE802154_6LO_FRAGMENT_H__
16
17 #include "ieee802154_6lo.h"
18 #include "ieee802154_frame.h"
19
20 #include <zephyr/net/net_pkt.h>
21 #include <zephyr/sys/slist.h>
22 #include <zephyr/types.h>
23
ieee802154_6lo_requires_fragmentation(struct net_pkt * pkt,uint8_t ll_hdr_len,uint8_t authtag_len)24 static inline bool ieee802154_6lo_requires_fragmentation(struct net_pkt *pkt, uint8_t ll_hdr_len,
25 uint8_t authtag_len)
26 {
27 return (ll_hdr_len + net_pkt_get_len(pkt) + authtag_len > IEEE802154_MTU);
28 }
29
ieee802154_6lo_fragment_ctx_init(struct ieee802154_6lo_fragment_ctx * ctx,struct net_pkt * pkt,uint16_t hdr_diff,bool iphc)30 static inline void ieee802154_6lo_fragment_ctx_init(struct ieee802154_6lo_fragment_ctx *ctx,
31 struct net_pkt *pkt, uint16_t hdr_diff,
32 bool iphc)
33 {
34 ctx->buf = pkt->buffer;
35 ctx->pos = ctx->buf->data;
36 ctx->hdr_diff = hdr_diff;
37 ctx->pkt_size = net_pkt_get_len(pkt) + (iphc ? hdr_diff : -1);
38 ctx->offset = 0U;
39 ctx->processed = 0U;
40 }
41
42 /**
43 * @brief Fragment IPv6 packet as per RFC 6282
44 *
45 * @details After IPv6 compression, transmission of IPv6 over 802.15.4
46 * needs to be fragmented. Every fragment will have fragmentation header
47 * data size, data offset, data tag and payload.
48 *
49 * @param ctx Pointer to valid fragmentation context
50 * @param frame_buf Pointer to valid buffer where to write the fragment
51 * @param ipch bool true for IPHC compression, false for IPv6 dispatch header
52 *
53 * @return pointer to the next buffer to be processed or NULL if no more
54 * buffers need processing
55 */
56 struct net_buf *ieee802154_6lo_fragment(struct ieee802154_6lo_fragment_ctx *ctx,
57 struct net_buf *frame_buf, bool iphc);
58
59 /**
60 * @brief Reassemble 802.15.4 fragments as per RFC 6282
61 *
62 * @details If the data does not fit into single fragment whole IPv6 packet
63 * comes in number of fragments. This function will reassemble them all as
64 * per data tag, data offset and data size. First packet is uncompressed
65 * immediately after reception.
66 *
67 * @param pkt Pointer to network fragment, which gets updated to full reassembled
68 * packet when verdict is NET_CONTINUE
69 *
70 * @return NET_CONTINUE reassembly done, pkt is complete
71 * NET_OK waiting for other fragments,
72 * NET_DROP invalid fragment.
73 */
74 enum net_verdict ieee802154_6lo_reassemble(struct net_pkt *pkt);
75
76 #endif /* __NET_IEEE802154_6LO_FRAGMENT_H__ */
77
