ba9486de4a
since it is impossible to track producer and consumer correctly if TCP/IP stack pass IOB directly to netdev Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
776 lines
24 KiB
C
776 lines
24 KiB
C
/****************************************************************************
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* net/sixlowpan/sixlowpan_framelist.c
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*
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* Copyright (C) 2017-2018 Gregory Nutt. All rights reserved.
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* Author: Gregory Nutt <gnutt@nuttx.org>
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*
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* Parts of this file derive from Contiki:
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*
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* Copyright (c) 2008, Swedish Institute of Computer Science.
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* All rights reserved.
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* Authors: Adam Dunkels <adam@sics.se>
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* Nicolas Tsiftes <nvt@sics.se>
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* Niclas Finne <nfi@sics.se>
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* Mathilde Durvy <mdurvy@cisco.com>
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* Julien Abeille <jabeille@cisco.com>
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* Joakim Eriksson <joakime@sics.se>
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* Joel Hoglund <joel@sics.se>
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the Institute nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#include <string.h>
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#include <assert.h>
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#include <errno.h>
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#include <debug.h>
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#include <nuttx/mm/iob.h>
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#include <nuttx/net/netdev.h>
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#include <nuttx/net/radiodev.h>
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#include <nuttx/wireless/ieee802154/ieee802154_mac.h>
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#include "utils/utils.h"
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#include "sixlowpan/sixlowpan_internal.h"
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#ifdef CONFIG_NET_6LOWPAN
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/****************************************************************************
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* Pre-processor Definitions
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****************************************************************************/
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/* Configuration ************************************************************/
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/* A single IOB must be big enough to hold a full frame. This we have to
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* check at run time. A IOB must also be big enough to hold the maximum MAC
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* header (25 bytes?) plus the FCS and have some amount of space left for
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* the payload.
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*/
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#define MAX_MACHDR 25 /* REVISIT: This is IEEE 802.15.4 specific */
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#if CONFIG_IOB_BUFSIZE < (SIXLOWPAN_MAC_FCSSIZE + MAX_MACHDR)
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# error CONFIG_IOB_BUFSIZE too small to hold a IEEE802.14.5 frame
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#endif
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/* There must be at least enough IOBs to hold the full MTU. Probably still
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* won't work unless there are a few more.
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*/
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#if CONFIG_NET_6LOWPAN_PKTSIZE > (CONFIG_IOB_BUFSIZE * CONFIG_IOB_NBUFFERS)
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# error Not enough IOBs to hold one full 6LoWPAN packet
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#endif
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/****************************************************************************
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* Private Functions
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****************************************************************************/
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/****************************************************************************
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* Name: sixlowpan_compress_ipv6hdr
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*
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* Description:
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* IPv6 dispatch "compression" function. Packets "Compression" when only
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* IPv6 dispatch is used
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*
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* There is no compression in this case, all fields are sent
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* inline. We just add the IPv6 dispatch byte before the packet.
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*
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* 0 1 2 3
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* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | IPv6 Dsp | IPv6 header and payload ...
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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*
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* Input Parameters:
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* ipv6hdr - Pointer to the IPv6 header to "compress"
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* fptr - Pointer to the beginning of the frame under construction
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*
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* Returned Value:
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* None
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*
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****************************************************************************/
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static int sixlowpan_compress_ipv6hdr(FAR const struct ipv6_hdr_s *ipv6hdr,
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FAR uint8_t *fptr)
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{
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/* Indicate the IPv6 dispatch and length */
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fptr[g_frame_hdrlen] = SIXLOWPAN_DISPATCH_IPV6;
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g_frame_hdrlen += SIXLOWPAN_IPV6_HDR_LEN;
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/* Copy the IPv6 header and adjust pointers */
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memcpy(&fptr[g_frame_hdrlen], ipv6hdr, IPv6_HDRLEN);
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g_frame_hdrlen += IPv6_HDRLEN;
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g_uncomp_hdrlen += IPv6_HDRLEN;
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return COMPRESS_HDR_INLINE;
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}
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/****************************************************************************
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* Name: sixlowpan_protosize
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*
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* Description:
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* Get the size of any uncompressed protocol header that follows the
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* IPv6 header.
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*
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****************************************************************************/
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static uint16_t sixlowpan_protosize(FAR const struct ipv6_hdr_s *ipv6hdr,
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FAR uint8_t *fptr)
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{
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uint16_t protosize;
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/* Copy the following protocol header, */
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switch (ipv6hdr->proto)
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{
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#ifdef CONFIG_NET_TCP
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case IP_PROTO_TCP:
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{
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FAR struct tcp_hdr_s *tcp =
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&((FAR struct ipv6tcp_hdr_s *)ipv6hdr)->tcp;
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/* The TCP header length is encoded in the top 4 bits of the
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* tcpoffset field (in units of 32-bit words).
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*/
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protosize = ((uint16_t)tcp->tcpoffset >> 4) << 2;
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}
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break;
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#endif
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#ifdef CONFIG_NET_UDP
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case IP_PROTO_UDP:
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protosize = UDP_HDRLEN;
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break;
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#endif
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#ifdef CONFIG_NET_ICMPv6
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case IP_PROTO_ICMP6:
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protosize = ICMPv6_HDRLEN;
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break;
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#endif
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default:
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nwarn("WARNING: Unrecognized proto: %u\n", ipv6hdr->proto);
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protosize = 0;
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break;
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}
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return protosize;
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}
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/****************************************************************************
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* Name: sixlowpan_ieee802154_metadata
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*
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* Description:
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* Create the meta data that describes the IEEE 802.15.4 MAC header.
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*
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* Input Parameters:
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* radio - The radio network driver instance
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* destmac - The IEEE802.15.4 MAC address of the destination
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* meta - Location to return the final metadata.
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*
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* Returned Value:
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* OK is returned on success; Otherwise a negated errno value is returned.
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*
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****************************************************************************/
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#ifdef CONFIG_WIRELESS_IEEE802154
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static int sixlowpan_ieee802154_metadata(FAR struct radio_driver_s *radio,
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FAR const struct netdev_varaddr_s *destmac,
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FAR union sixlowpan_metadata_u *meta)
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{
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struct ieee802_txmetadata_s pktmeta;
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int ret;
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/* Reset frame meta data */
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memset(&pktmeta, 0, sizeof(struct ieee802_txmetadata_s));
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pktmeta.xmits = CONFIG_NET_6LOWPAN_MAX_MACTRANSMITS;
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/* Set stream mode for all TCP packets, except FIN packets. */
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#if 0 /* Currently the frame type is always data */
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if (ipv6->proto == IP_PROTO_TCP)
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{
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FAR const struct tcp_hdr_s *tcp =
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&((FAR const struct ipv6tcp_hdr_s *)ipv6)->tcp;
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if ((tcp->flags & TCP_FIN) == 0 &&
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(tcp->flags & TCP_CTL) != TCP_ACK)
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{
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pktmeta.type = FRAME_ATTR_TYPE_STREAM;
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}
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else if ((tcp->flags & TCP_FIN) == TCP_FIN)
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{
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pktmeta.type = FRAME_ATTR_TYPE_STREAM_END;
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}
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}
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#endif
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/* Set the source and destination address. The source MAC address
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* is a fixed size, determined by a configuration setting. The
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* destination MAC address many be either short or extended.
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*/
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#ifdef CONFIG_NET_6LOWPAN_EXTENDEDADDR
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pktmeta.sextended = TRUE;
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sixlowpan_eaddrcopy(pktmeta.source.nm_addr,
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&radio->r_dev.d_mac.radio.nv_addr);
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#else
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sixlowpan_saddrcopy(pktmeta.source.nm_addr,
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&radio->r_dev.d_mac.radio.nv_addr);
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#endif
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/* Copy the destination node address into the meta data */
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if (destmac->nv_addrlen == NET_6LOWPAN_EADDRSIZE)
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{
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pktmeta.dextended = TRUE;
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sixlowpan_eaddrcopy(pktmeta.dest.nm_addr, destmac->nv_addr);
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}
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else
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{
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DEBUGASSERT(destmac->nv_addrlen == NET_6LOWPAN_SADDRSIZE);
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sixlowpan_saddrcopy(pktmeta.dest.nm_addr, destmac->nv_addr);
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}
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/* Get the destination PAN ID.
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*
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* REVISIT: For now I am assuming that the source and destination
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* PAN IDs are the same.
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*/
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sixlowpan_src_panid(radio, pktmeta.dpanid);
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/* Based on the collected attributes and addresses, construct the MAC meta
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* data structure that we need to interface with the IEEE802.15.4 MAC (we
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* will update the MSDU payload size when the IOB has been setup).
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*/
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ret = sixlowpan_meta_data(radio, &pktmeta, &meta->ieee802154);
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if (ret < 0)
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{
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nerr("ERROR: sixlowpan_meta_data() failed: %d\n", ret);
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}
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return ret;
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}
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#endif
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/****************************************************************************
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* Name: sixlowpan_pktradio_metadata
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*
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* Description:
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* Create the meta data that describes the MAC header for a generic radio.
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*
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* Input Parameters:
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* radio - The radio network driver instance
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* destmac - The radio-specific MAC address of the destination
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* meta - Location to return the final metadata.
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*
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* Returned Value:
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* OK is returned on success; Otherwise a negated errno value is returned.
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*
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****************************************************************************/
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#ifdef CONFIG_WIRELESS_PKTRADIO
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static int sixlowpan_pktradio_metadata(FAR struct radio_driver_s *radio,
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FAR const struct netdev_varaddr_s *destmac,
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FAR union sixlowpan_metadata_u *meta)
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{
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FAR struct pktradio_metadata_s *pktmeta = &meta->pktradio;
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/* Reset the meta data */
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memset(pktmeta, 0, sizeof(struct pktradio_metadata_s));
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/* Set the source address */
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pktmeta->pm_src.pa_addrlen = radio->r_dev.d_mac.radio.nv_addrlen;
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memcpy(pktmeta->pm_src.pa_addr,
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radio->r_dev.d_mac.radio.nv_addr,
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radio->r_dev.d_mac.radio.nv_addrlen);
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/* Set the destination address.
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* REVISIT: Do we need to check for multicast or broadcast addresses
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* here?
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*/
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pktmeta->pm_dest.pa_addrlen = destmac->nv_addrlen;
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memcpy(pktmeta->pm_dest.pa_addr, destmac->nv_addr, destmac->nv_addrlen);
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return OK;
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}
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#endif
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/****************************************************************************
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* Public Functions
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****************************************************************************/
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/****************************************************************************
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* Name: sixlowpan_queue_frames
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*
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* Description:
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* Process an outgoing UDP, TCP, or ICMPv6 packet. This function is
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* called from send event handler when a TX poll is received. It
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* formats the list of frames to be sent by the IEEE802.15.4 MAC driver.
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*
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* The payload data is in the caller 'buf' and is of length 'buflen'.
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* Compressed headers will be added and if necessary the packet is
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* fragmented. The resulting packet/fragments are submitted to the MAC
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* where they are queue for transfer.
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*
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* Input Parameters:
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* radio - The radio network driver instance
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* ipv6 - IPv6 header followed by TCP, UDP, or ICMPv6 header.
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* buf - Beginning of the packet packet to send (with IPv6 + protocol
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* headers)
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* buflen - Length of data to send (includes IPv6 and protocol headers)
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* destmac - The IEEE802.15.4 MAC address of the destination
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*
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* Returned Value:
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* Ok is returned on success; Otherwise a negated errno value is returned.
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* This function is expected to fail if the driver is not an IEEE802.15.4
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* MAC network driver. In that case, the UDP/TCP will fall back to normal
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* IPv4/IPv6 formatting.
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*
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* Assumptions:
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* Called with the network locked.
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*
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****************************************************************************/
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int sixlowpan_queue_frames(FAR struct radio_driver_s *radio,
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FAR const struct ipv6_hdr_s *ipv6,
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FAR const void *buf, size_t buflen,
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FAR const struct netdev_varaddr_s *destmac)
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{
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union sixlowpan_metadata_u meta;
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FAR struct iob_s *iob;
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FAR uint8_t *fptr;
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int framer_hdrlen;
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struct netdev_varaddr_s bcastmac;
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uint16_t framelen;
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uint16_t pktlen;
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uint16_t paysize;
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uint16_t outlen = 0;
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uint8_t protosize;
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int ret;
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ninfo("buflen=%lu\n", (unsigned long)buflen);
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/* Initialize global data. Locking the network guarantees that we have
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* exclusive use of the global values for intermediate calculations.
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*/
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g_uncomp_hdrlen = 0;
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g_frame_hdrlen = 0;
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protosize = 0;
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/* The destination address will be tagged to each outbound packet. If the
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* argument destmac is NULL, we are sending a broadcast packet.
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*/
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if (destmac == NULL)
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{
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memset(&bcastmac, 0, sizeof(struct netdev_varaddr_s));
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destmac = &bcastmac;
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}
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/* Pre-allocate the IOB to hold frame or the first fragment, waiting if
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* necessary.
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*/
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iob = net_ioballoc(false);
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DEBUGASSERT(iob != NULL);
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/* Initialize the IOB */
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iob->io_flink = NULL;
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iob->io_len = 0;
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iob->io_offset = 0;
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iob->io_pktlen = 0;
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fptr = iob->io_data;
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ninfo("Sending packet length %zd\n", buflen);
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/* Get the metadata that describes the MAC header on the packet */
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#ifdef CONFIG_WIRELESS_IEEE802154
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#ifdef CONFIG_WIRELESS_PKTRADIO
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if (radio->r_dev.d_lltype == NET_LL_IEEE802154)
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#endif
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{
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ret = sixlowpan_ieee802154_metadata(radio, destmac, &meta);
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}
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#endif
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#ifdef CONFIG_WIRELESS_PKTRADIO
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#ifdef CONFIG_WIRELESS_IEEE802154
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else
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#endif
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{
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ret = sixlowpan_pktradio_metadata(radio, destmac, &meta);
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}
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#endif
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/* Pre-calculate frame header length. */
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framer_hdrlen = sixlowpan_frame_hdrlen(radio, &meta);
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if (framer_hdrlen < 0)
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{
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/* Failed to determine the size of the header failed. */
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nerr("ERROR: sixlowpan_frame_hdrlen() failed: %d\n", framer_hdrlen);
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return framer_hdrlen;
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}
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/* This sill be the initial offset into io_data. Valid data begins at
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* this offset and must be reflected in io_offset.
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*/
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g_frame_hdrlen = framer_hdrlen;
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iob->io_offset = framer_hdrlen;
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#ifndef CONFIG_NET_6LOWPAN_COMPRESSION_IPv6
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if (buflen >= CONFIG_NET_6LOWPAN_COMPRESSION_THRESHOLD)
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{
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/* Try to compress the headers */
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#if defined(CONFIG_NET_6LOWPAN_COMPRESSION_HC1)
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ret = sixlowpan_compresshdr_hc1(radio, ipv6, destmac, fptr);
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#elif defined(CONFIG_NET_6LOWPAN_COMPRESSION_HC06)
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ret = sixlowpan_compresshdr_hc06(radio, ipv6, destmac, fptr);
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#else
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# error No compression specified
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#endif
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}
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else
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#endif /* !CONFIG_NET_6LOWPAN_COMPRESSION_IPv6 */
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{
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/* Small.. use IPv6 dispatch (no compression) */
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ret = sixlowpan_compress_ipv6hdr(ipv6, fptr);
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}
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/* Get the size of any uncompressed protocol headers */
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if (ret == COMPRESS_HDR_INLINE)
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{
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protosize = sixlowpan_protosize(ipv6, fptr);
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}
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ninfo("Header of length=%u protosize=%u\n", g_frame_hdrlen, protosize);
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/* Get the maximum packet size supported by this radio. */
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ret = sixlowpan_radio_framelen(radio);
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if (ret < 0)
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{
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nerr("ERROR: sixlowpan_radio_framelen() failed: %d\n", ret);
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return ret;
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}
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/* Limit to the maximum size supported by the IOBs */
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if (ret > CONFIG_IOB_BUFSIZE)
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{
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ret = CONFIG_IOB_BUFSIZE;
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}
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/* Reserve space at the end for any FCS that the hardware may include
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* in the payload.
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*/
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ret -= SIXLOWPAN_MAC_FCSSIZE;
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if (ret < MAX_MACHDR || ret > UINT16_MAX)
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{
|
||
nerr("ERROR: Invalid frame size: %d\n", ret);
|
||
return ret;
|
||
}
|
||
|
||
framelen = (uint16_t)ret;
|
||
|
||
/* Check if we need to fragment the packet into several frames.
|
||
* We may need to reserve space at the end of the frame for a 2-byte FCS
|
||
*/
|
||
|
||
if (buflen > (framelen - g_frame_hdrlen - protosize))
|
||
{
|
||
/* qhead will hold the generated frame list; frames will be
|
||
* added at qtail.
|
||
*/
|
||
|
||
FAR struct sixlowpan_reassbuf_s *reass;
|
||
FAR struct iob_s *qhead;
|
||
FAR struct iob_s *qtail;
|
||
FAR uint8_t *frame1;
|
||
FAR uint8_t *fragptr;
|
||
uint16_t frag1_hdrlen;
|
||
|
||
/* Recover the reassembly buffer from the driver d_buf. */
|
||
|
||
reass = (FAR struct sixlowpan_reassbuf_s *)radio->r_dev.d_buf;
|
||
DEBUGASSERT(reass != NULL);
|
||
|
||
/* The outbound IPv6 packet is too large to fit into a single 15.4
|
||
* packet, so we fragment it into multiple packets and send them.
|
||
* The first fragment contains frag1 dispatch, then
|
||
* IPv6/HC1/HC06/HC_UDP dispatchs/headers.
|
||
* The following fragments contain only the fragn dispatch.
|
||
*/
|
||
|
||
ninfo("Sending fragmented packet length %zd\n", buflen);
|
||
|
||
/* Create 1st Fragment */
|
||
|
||
/* Move HC1/HC06/IPv6 header to make space for the FRAG1 header at the
|
||
* beginning of the frame.
|
||
*/
|
||
|
||
fragptr = fptr + framer_hdrlen;
|
||
memmove(fragptr + SIXLOWPAN_FRAG1_HDR_LEN, fragptr,
|
||
g_frame_hdrlen - framer_hdrlen);
|
||
|
||
/* Setup up the fragment header.
|
||
*
|
||
* The fragment header contains three fields: Datagram size, datagram
|
||
* tag and datagram offset:
|
||
*
|
||
* 1. Datagram size describes the total (un-fragmented) payload.
|
||
* 2. Datagram tag identifies the set of fragments and is used to
|
||
* match fragments of the same payload.
|
||
* 3. Datagram offset identifies the fragment’s offset within the
|
||
* unfragmented payload.
|
||
*
|
||
* The fragment header length is 4 bytes for the first header and 5
|
||
* bytes for all subsequent headers.
|
||
*/
|
||
|
||
pktlen = buflen + g_uncomp_hdrlen + protosize;
|
||
PUTHOST16(fragptr, SIXLOWPAN_FRAG_DISPATCH_SIZE,
|
||
((SIXLOWPAN_DISPATCH_FRAG1 << 8) | pktlen));
|
||
PUTHOST16(fragptr, SIXLOWPAN_FRAG_TAG, reass->rb_dgramtag);
|
||
|
||
g_frame_hdrlen += SIXLOWPAN_FRAG1_HDR_LEN;
|
||
|
||
/* Copy any uncompressed protocol headers that must appear only in th
|
||
* first fragment.
|
||
*/
|
||
|
||
if (protosize > 0)
|
||
{
|
||
FAR uint8_t *src = (FAR uint8_t *)ipv6 + IPv6_HDRLEN;
|
||
memcpy(fptr + g_frame_hdrlen, src, protosize);
|
||
}
|
||
|
||
/* Copy payload and enqueue. NOTE that the size is a multiple of eight
|
||
* bytes.
|
||
*/
|
||
|
||
paysize = (framelen - g_frame_hdrlen) & ~7;
|
||
memcpy(fptr + g_frame_hdrlen + protosize, buf, paysize - protosize);
|
||
|
||
/* Set outlen to what we already sent from the IP payload */
|
||
|
||
iob->io_len = paysize + g_frame_hdrlen;
|
||
outlen = paysize;
|
||
|
||
ninfo("First fragment: length %d, tag %d\n",
|
||
paysize, reass->rb_dgramtag);
|
||
sixlowpan_dumpbuffer("Outgoing frame",
|
||
(FAR const uint8_t *)iob->io_data, iob->io_len);
|
||
|
||
/* Add the first frame to the IOB queue */
|
||
|
||
ninfo("Queuing frame io_len=%u io_offset=%u\n",
|
||
iob->io_len, iob->io_offset);
|
||
|
||
qhead = iob;
|
||
qtail = iob;
|
||
|
||
/* Keep track of the total amount of data queue */
|
||
|
||
iob->io_pktlen = iob->io_len;
|
||
|
||
/* Create following fragments */
|
||
|
||
frame1 = iob->io_data;
|
||
frag1_hdrlen = g_frame_hdrlen;
|
||
|
||
while (outlen < (buflen + protosize))
|
||
{
|
||
uint16_t fragn_hdrlen;
|
||
|
||
/* Allocate an IOB to hold the next fragment, waiting if
|
||
* necessary.
|
||
*/
|
||
|
||
iob = net_ioballoc(false);
|
||
DEBUGASSERT(iob != NULL);
|
||
|
||
/* Initialize the IOB */
|
||
|
||
iob->io_flink = NULL;
|
||
iob->io_len = 0;
|
||
iob->io_offset = framer_hdrlen;
|
||
iob->io_pktlen = 0;
|
||
fptr = iob->io_data;
|
||
|
||
/* Copy the HC1/HC06/IPv6 header the frame header from first
|
||
* frame, into the correct location after the FRAGN header
|
||
* of subsequent frames.
|
||
*/
|
||
|
||
fragptr = fptr + framer_hdrlen;
|
||
memcpy(fragptr + SIXLOWPAN_FRAGN_HDR_LEN,
|
||
frame1 + framer_hdrlen + SIXLOWPAN_FRAG1_HDR_LEN,
|
||
frag1_hdrlen - framer_hdrlen);
|
||
fragn_hdrlen = frag1_hdrlen - SIXLOWPAN_FRAG1_HDR_LEN;
|
||
|
||
/* Setup up the FRAGN header after the frame header. */
|
||
|
||
PUTHOST16(fragptr, SIXLOWPAN_FRAG_DISPATCH_SIZE,
|
||
((SIXLOWPAN_DISPATCH_FRAGN << 8) | pktlen));
|
||
PUTHOST16(fragptr, SIXLOWPAN_FRAG_TAG, reass->rb_dgramtag);
|
||
fragptr[SIXLOWPAN_FRAG_OFFSET] = outlen >> 3;
|
||
|
||
fragn_hdrlen += SIXLOWPAN_FRAGN_HDR_LEN;
|
||
|
||
/* Copy payload and enqueue.
|
||
*
|
||
* Check for the last fragment.
|
||
*/
|
||
|
||
paysize = (framelen - fragn_hdrlen) & SIXLOWPAN_DISPATCH_FRAG_MASK;
|
||
if (paysize > buflen - outlen + protosize)
|
||
{
|
||
/* Last fragment, truncate to the correct length */
|
||
|
||
paysize = buflen - outlen + protosize;
|
||
}
|
||
|
||
memcpy(fptr + fragn_hdrlen, buf + outlen - protosize, paysize);
|
||
|
||
/* Set outlen to what we already sent from the IP payload */
|
||
|
||
iob->io_len = paysize + fragn_hdrlen;
|
||
outlen += paysize;
|
||
|
||
ninfo("Fragment offset=%d, paysize=%d, rb_dgramtag=%d\n",
|
||
outlen >> 3, paysize, reass->rb_dgramtag);
|
||
|
||
sixlowpan_dumpbuffer("Outgoing frame",
|
||
(FAR const uint8_t *)iob->io_data,
|
||
iob->io_len);
|
||
|
||
/* Add the next frame to the tail of the IOB queue */
|
||
|
||
ninfo("Queuing frame io_len=%u io_offset=%u\n",
|
||
iob->io_len, iob->io_offset);
|
||
|
||
qtail->io_flink = iob;
|
||
qtail = iob;
|
||
|
||
/* Keep track of the total amount of data queue */
|
||
|
||
qhead->io_pktlen += iob->io_len;
|
||
}
|
||
|
||
/* Submit all of the fragments to the MAC. We send all frames back-
|
||
* to-back like this to minimize any possible condition where some
|
||
* frame which is not a fragment from this sequence from intervening.
|
||
*/
|
||
|
||
for (iob = qhead; iob != NULL; iob = qhead)
|
||
{
|
||
/* Remove the IOB containing the frame from the list */
|
||
|
||
qhead = iob->io_flink;
|
||
iob->io_flink = NULL;
|
||
|
||
/* And submit the frame to the MAC */
|
||
|
||
ninfo("Submitting frame\n");
|
||
ret = sixlowpan_frame_submit(radio, &meta, iob);
|
||
if (ret < 0)
|
||
{
|
||
nerr("ERROR: sixlowpan_frame_submit() failed: %d\n", ret);
|
||
}
|
||
}
|
||
|
||
/* Update the datagram TAG value */
|
||
|
||
reass->rb_dgramtag++;
|
||
}
|
||
else
|
||
{
|
||
/* The packet does not need to be fragmented just copy the "payload"
|
||
* and send in one frame.
|
||
*/
|
||
|
||
/* Copy any uncompressed protocol headers that must appear only in th
|
||
* first fragment.
|
||
*/
|
||
|
||
if (protosize > 0)
|
||
{
|
||
FAR uint8_t *src = (FAR uint8_t *)ipv6 + IPv6_HDRLEN;
|
||
memcpy(fptr + g_frame_hdrlen, src, protosize);
|
||
}
|
||
|
||
/* Copy the payload into the frame. */
|
||
|
||
memcpy(fptr + g_frame_hdrlen + protosize, buf, buflen);
|
||
iob->io_len = buflen + g_frame_hdrlen + protosize;
|
||
iob->io_pktlen = iob->io_len;
|
||
|
||
ninfo("Non-fragmented: length %d\n", iob->io_len);
|
||
sixlowpan_dumpbuffer("Outgoing frame",
|
||
(FAR const uint8_t *)iob->io_data, iob->io_len);
|
||
|
||
/* And submit the frame to the MAC */
|
||
|
||
ninfo("Submitting frame length=%u io_offset=%u\n",
|
||
iob->io_len, iob->io_offset);
|
||
|
||
ret = sixlowpan_frame_submit(radio, &meta, iob);
|
||
if (ret < 0)
|
||
{
|
||
nerr("ERROR: sixlowpan_frame_submit() failed: %d\n", ret);
|
||
}
|
||
}
|
||
|
||
return OK;
|
||
}
|
||
|
||
#endif /* CONFIG_NET_6LOWPAN */
|