![Alexander Aring](/assets/img/avatar_default.png)
This patch changes the lowpan_header_decompress function by removing inklayer related information from parameters. This is currently for supporting short and extended address for iphc handling in 802154. We don't support short address handling anyway right now, but there exists already code for handling short addresses in lowpan_header_decompress. The address parameters are also changed to a void pointer, so 6LoWPAN linklayer specific code can put complex structures as these parameters and cast it again inside the generic code by evaluating linklayer type before. The order is also changed by destination address at first and then source address, which is the same like all others functions where destination is always the first, memcpy, dev_hard_header, lowpan_header_compress, etc. This patch also moves the fetching of iphc values from 6LoWPAN linklayer specific code into the generic branch. Signed-off-by: Alexander Aring <alex.aring@gmail.com> Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
645 lines
18 KiB
C
645 lines
18 KiB
C
/*
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* Copyright 2011, Siemens AG
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* written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
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*/
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/* Based on patches from Jon Smirl <jonsmirl@gmail.com>
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* Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2
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* as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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*/
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/* Jon's code is based on 6lowpan implementation for Contiki which is:
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* Copyright (c) 2008, Swedish Institute of Computer Science.
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* All rights reserved.
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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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* 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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#include <linux/bitops.h>
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#include <linux/if_arp.h>
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#include <linux/netdevice.h>
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#include <net/6lowpan.h>
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#include <net/ipv6.h>
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/* special link-layer handling */
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#include <net/mac802154.h>
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#include "nhc.h"
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static inline void iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr,
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const void *lladdr)
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{
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/* fe:80::XXXX:XXXX:XXXX:XXXX
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* \_________________/
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* hwaddr
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*/
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ipaddr->s6_addr[0] = 0xFE;
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ipaddr->s6_addr[1] = 0x80;
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memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN);
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/* second bit-flip (Universe/Local)
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* is done according RFC2464
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*/
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ipaddr->s6_addr[8] ^= 0x02;
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}
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static inline void iphc_uncompress_802154_lladdr(struct in6_addr *ipaddr,
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const void *lladdr)
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{
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const struct ieee802154_addr *addr = lladdr;
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u8 eui64[EUI64_ADDR_LEN] = { };
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switch (addr->mode) {
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case IEEE802154_ADDR_LONG:
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ieee802154_le64_to_be64(eui64, &addr->extended_addr);
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iphc_uncompress_eui64_lladdr(ipaddr, eui64);
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break;
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case IEEE802154_ADDR_SHORT:
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/* fe:80::ff:fe00:XXXX
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* \__/
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* short_addr
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*
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* Universe/Local bit is zero.
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*/
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ipaddr->s6_addr[0] = 0xFE;
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ipaddr->s6_addr[1] = 0x80;
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ipaddr->s6_addr[11] = 0xFF;
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ipaddr->s6_addr[12] = 0xFE;
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ieee802154_le16_to_be16(&ipaddr->s6_addr16[7],
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&addr->short_addr);
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break;
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default:
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/* should never handled and filtered by 802154 6lowpan */
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WARN_ON_ONCE(1);
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break;
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}
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}
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/* Uncompress address function for source and
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* destination address(non-multicast).
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*
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* address_mode is sam value or dam value.
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*/
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static int uncompress_addr(struct sk_buff *skb, const struct net_device *dev,
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struct in6_addr *ipaddr, u8 address_mode,
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const void *lladdr)
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{
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bool fail;
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switch (address_mode) {
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case LOWPAN_IPHC_ADDR_00:
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/* for global link addresses */
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fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16);
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break;
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case LOWPAN_IPHC_ADDR_01:
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/* fe:80::XXXX:XXXX:XXXX:XXXX */
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ipaddr->s6_addr[0] = 0xFE;
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ipaddr->s6_addr[1] = 0x80;
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fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8);
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break;
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case LOWPAN_IPHC_ADDR_02:
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/* fe:80::ff:fe00:XXXX */
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ipaddr->s6_addr[0] = 0xFE;
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ipaddr->s6_addr[1] = 0x80;
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ipaddr->s6_addr[11] = 0xFF;
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ipaddr->s6_addr[12] = 0xFE;
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fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2);
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break;
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case LOWPAN_IPHC_ADDR_03:
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fail = false;
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switch (lowpan_priv(dev)->lltype) {
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case LOWPAN_LLTYPE_IEEE802154:
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iphc_uncompress_802154_lladdr(ipaddr, lladdr);
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break;
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default:
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iphc_uncompress_eui64_lladdr(ipaddr, lladdr);
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break;
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}
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break;
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default:
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pr_debug("Invalid address mode value: 0x%x\n", address_mode);
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return -EINVAL;
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}
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if (fail) {
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pr_debug("Failed to fetch skb data\n");
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return -EIO;
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}
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raw_dump_inline(NULL, "Reconstructed ipv6 addr is",
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ipaddr->s6_addr, 16);
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return 0;
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}
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/* Uncompress address function for source context
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* based address(non-multicast).
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*/
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static int uncompress_context_based_src_addr(struct sk_buff *skb,
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struct in6_addr *ipaddr,
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const u8 sam)
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{
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switch (sam) {
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case LOWPAN_IPHC_ADDR_00:
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/* unspec address ::
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* Do nothing, address is already ::
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*/
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break;
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case LOWPAN_IPHC_ADDR_01:
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/* TODO */
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case LOWPAN_IPHC_ADDR_02:
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/* TODO */
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case LOWPAN_IPHC_ADDR_03:
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/* TODO */
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netdev_warn(skb->dev, "SAM value 0x%x not supported\n", sam);
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return -EINVAL;
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default:
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pr_debug("Invalid sam value: 0x%x\n", sam);
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return -EINVAL;
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}
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raw_dump_inline(NULL,
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"Reconstructed context based ipv6 src addr is",
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ipaddr->s6_addr, 16);
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return 0;
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}
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/* Uncompress function for multicast destination address,
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* when M bit is set.
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*/
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static int lowpan_uncompress_multicast_daddr(struct sk_buff *skb,
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struct in6_addr *ipaddr,
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const u8 dam)
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{
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bool fail;
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switch (dam) {
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case LOWPAN_IPHC_DAM_00:
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/* 00: 128 bits. The full address
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* is carried in-line.
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*/
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fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16);
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break;
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case LOWPAN_IPHC_DAM_01:
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/* 01: 48 bits. The address takes
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* the form ffXX::00XX:XXXX:XXXX.
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*/
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ipaddr->s6_addr[0] = 0xFF;
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fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1);
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fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[11], 5);
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break;
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case LOWPAN_IPHC_DAM_10:
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/* 10: 32 bits. The address takes
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* the form ffXX::00XX:XXXX.
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*/
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ipaddr->s6_addr[0] = 0xFF;
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fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1);
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fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[13], 3);
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break;
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case LOWPAN_IPHC_DAM_11:
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/* 11: 8 bits. The address takes
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* the form ff02::00XX.
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*/
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ipaddr->s6_addr[0] = 0xFF;
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ipaddr->s6_addr[1] = 0x02;
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fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[15], 1);
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break;
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default:
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pr_debug("DAM value has a wrong value: 0x%x\n", dam);
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return -EINVAL;
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}
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if (fail) {
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pr_debug("Failed to fetch skb data\n");
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return -EIO;
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}
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raw_dump_inline(NULL, "Reconstructed ipv6 multicast addr is",
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ipaddr->s6_addr, 16);
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return 0;
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}
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/* TTL uncompression values */
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static const u8 lowpan_ttl_values[] = { 0, 1, 64, 255 };
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int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
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const void *daddr, const void *saddr)
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{
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struct ipv6hdr hdr = {};
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u8 iphc0, iphc1, tmp, num_context = 0;
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int err;
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raw_dump_table(__func__, "raw skb data dump uncompressed",
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skb->data, skb->len);
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if (lowpan_fetch_skb_u8(skb, &iphc0) ||
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lowpan_fetch_skb_u8(skb, &iphc1))
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return -EINVAL;
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/* another if the CID flag is set */
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if (iphc1 & LOWPAN_IPHC_CID) {
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pr_debug("CID flag is set, increase header with one\n");
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if (lowpan_fetch_skb(skb, &num_context, sizeof(num_context)))
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return -EINVAL;
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}
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hdr.version = 6;
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/* Traffic Class and Flow Label */
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switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) {
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/* Traffic Class and FLow Label carried in-line
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* ECN + DSCP + 4-bit Pad + Flow Label (4 bytes)
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*/
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case 0: /* 00b */
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if (lowpan_fetch_skb(skb, &tmp, sizeof(tmp)))
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return -EINVAL;
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memcpy(&hdr.flow_lbl, &skb->data[0], 3);
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skb_pull(skb, 3);
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hdr.priority = ((tmp >> 2) & 0x0f);
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hdr.flow_lbl[0] = ((tmp >> 2) & 0x30) | (tmp << 6) |
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(hdr.flow_lbl[0] & 0x0f);
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break;
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/* Traffic class carried in-line
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* ECN + DSCP (1 byte), Flow Label is elided
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*/
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case 2: /* 10b */
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if (lowpan_fetch_skb(skb, &tmp, sizeof(tmp)))
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return -EINVAL;
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hdr.priority = ((tmp >> 2) & 0x0f);
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hdr.flow_lbl[0] = ((tmp << 6) & 0xC0) | ((tmp >> 2) & 0x30);
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break;
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/* Flow Label carried in-line
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* ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided
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*/
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case 1: /* 01b */
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if (lowpan_fetch_skb(skb, &tmp, sizeof(tmp)))
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return -EINVAL;
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hdr.flow_lbl[0] = (tmp & 0x0F) | ((tmp >> 2) & 0x30);
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memcpy(&hdr.flow_lbl[1], &skb->data[0], 2);
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skb_pull(skb, 2);
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break;
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/* Traffic Class and Flow Label are elided */
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case 3: /* 11b */
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break;
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default:
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break;
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}
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/* Next Header */
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if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) {
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/* Next header is carried inline */
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if (lowpan_fetch_skb(skb, &hdr.nexthdr, sizeof(hdr.nexthdr)))
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return -EINVAL;
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pr_debug("NH flag is set, next header carried inline: %02x\n",
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hdr.nexthdr);
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}
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/* Hop Limit */
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if ((iphc0 & 0x03) != LOWPAN_IPHC_TTL_I) {
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hdr.hop_limit = lowpan_ttl_values[iphc0 & 0x03];
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} else {
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if (lowpan_fetch_skb(skb, &hdr.hop_limit,
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sizeof(hdr.hop_limit)))
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return -EINVAL;
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}
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/* Extract SAM to the tmp variable */
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tmp = ((iphc1 & LOWPAN_IPHC_SAM) >> LOWPAN_IPHC_SAM_BIT) & 0x03;
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if (iphc1 & LOWPAN_IPHC_SAC) {
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/* Source address context based uncompression */
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pr_debug("SAC bit is set. Handle context based source address.\n");
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err = uncompress_context_based_src_addr(skb, &hdr.saddr, tmp);
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} else {
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/* Source address uncompression */
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pr_debug("source address stateless compression\n");
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err = uncompress_addr(skb, dev, &hdr.saddr, tmp, saddr);
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}
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/* Check on error of previous branch */
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if (err)
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return -EINVAL;
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/* Extract DAM to the tmp variable */
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tmp = ((iphc1 & LOWPAN_IPHC_DAM_11) >> LOWPAN_IPHC_DAM_BIT) & 0x03;
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/* check for Multicast Compression */
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if (iphc1 & LOWPAN_IPHC_M) {
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if (iphc1 & LOWPAN_IPHC_DAC) {
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pr_debug("dest: context-based mcast compression\n");
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/* TODO: implement this */
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} else {
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err = lowpan_uncompress_multicast_daddr(skb, &hdr.daddr,
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tmp);
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if (err)
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return -EINVAL;
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}
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} else {
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err = uncompress_addr(skb, dev, &hdr.daddr, tmp, daddr);
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pr_debug("dest: stateless compression mode %d dest %pI6c\n",
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tmp, &hdr.daddr);
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if (err)
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return -EINVAL;
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}
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/* Next header data uncompression */
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if (iphc0 & LOWPAN_IPHC_NH_C) {
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err = lowpan_nhc_do_uncompression(skb, dev, &hdr);
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if (err < 0)
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return err;
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} else {
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err = skb_cow(skb, sizeof(hdr));
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if (unlikely(err))
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return err;
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}
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switch (lowpan_priv(dev)->lltype) {
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case LOWPAN_LLTYPE_IEEE802154:
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if (lowpan_802154_cb(skb)->d_size)
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hdr.payload_len = htons(lowpan_802154_cb(skb)->d_size -
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sizeof(struct ipv6hdr));
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else
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hdr.payload_len = htons(skb->len);
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break;
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default:
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hdr.payload_len = htons(skb->len);
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break;
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}
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pr_debug("skb headroom size = %d, data length = %d\n",
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skb_headroom(skb), skb->len);
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pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n\t"
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"nexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
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hdr.version, ntohs(hdr.payload_len), hdr.nexthdr,
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hdr.hop_limit, &hdr.daddr);
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skb_push(skb, sizeof(hdr));
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skb_reset_network_header(skb);
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skb_copy_to_linear_data(skb, &hdr, sizeof(hdr));
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raw_dump_table(__func__, "raw header dump", (u8 *)&hdr, sizeof(hdr));
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return 0;
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}
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EXPORT_SYMBOL_GPL(lowpan_header_decompress);
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static u8 lowpan_compress_addr_64(u8 **hc_ptr, u8 shift,
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const struct in6_addr *ipaddr,
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const unsigned char *lladdr)
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{
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u8 val = 0;
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if (is_addr_mac_addr_based(ipaddr, lladdr)) {
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val = 3; /* 0-bits */
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pr_debug("address compression 0 bits\n");
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} else if (lowpan_is_iid_16_bit_compressable(ipaddr)) {
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/* compress IID to 16 bits xxxx::XXXX */
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lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[7], 2);
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val = 2; /* 16-bits */
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raw_dump_inline(NULL, "Compressed ipv6 addr is (16 bits)",
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*hc_ptr - 2, 2);
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} else {
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/* do not compress IID => xxxx::IID */
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lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[4], 8);
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val = 1; /* 64-bits */
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raw_dump_inline(NULL, "Compressed ipv6 addr is (64 bits)",
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*hc_ptr - 8, 8);
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}
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return rol8(val, shift);
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}
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int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
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const void *daddr, const void *saddr)
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{
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u8 tmp, iphc0, iphc1, *hc_ptr;
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struct ipv6hdr *hdr;
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u8 head[LOWPAN_IPHC_MAX_HC_BUF_LEN] = {};
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int ret, addr_type;
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if (skb->protocol != htons(ETH_P_IPV6))
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return -EINVAL;
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hdr = ipv6_hdr(skb);
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hc_ptr = head + 2;
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pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n"
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"\tnexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
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hdr->version, ntohs(hdr->payload_len), hdr->nexthdr,
|
|
hdr->hop_limit, &hdr->daddr);
|
|
|
|
raw_dump_table(__func__, "raw skb network header dump",
|
|
skb_network_header(skb), sizeof(struct ipv6hdr));
|
|
|
|
/* As we copy some bit-length fields, in the IPHC encoding bytes,
|
|
* we sometimes use |=
|
|
* If the field is 0, and the current bit value in memory is 1,
|
|
* this does not work. We therefore reset the IPHC encoding here
|
|
*/
|
|
iphc0 = LOWPAN_DISPATCH_IPHC;
|
|
iphc1 = 0;
|
|
|
|
/* TODO: context lookup */
|
|
|
|
raw_dump_inline(__func__, "saddr", saddr, EUI64_ADDR_LEN);
|
|
raw_dump_inline(__func__, "daddr", daddr, EUI64_ADDR_LEN);
|
|
|
|
raw_dump_table(__func__, "sending raw skb network uncompressed packet",
|
|
skb->data, skb->len);
|
|
|
|
/* Traffic class, flow label
|
|
* If flow label is 0, compress it. If traffic class is 0, compress it
|
|
* We have to process both in the same time as the offset of traffic
|
|
* class depends on the presence of version and flow label
|
|
*/
|
|
|
|
/* hc format of TC is ECN | DSCP , original one is DSCP | ECN */
|
|
tmp = (hdr->priority << 4) | (hdr->flow_lbl[0] >> 4);
|
|
tmp = ((tmp & 0x03) << 6) | (tmp >> 2);
|
|
|
|
if (((hdr->flow_lbl[0] & 0x0F) == 0) &&
|
|
(hdr->flow_lbl[1] == 0) && (hdr->flow_lbl[2] == 0)) {
|
|
/* flow label can be compressed */
|
|
iphc0 |= LOWPAN_IPHC_FL_C;
|
|
if ((hdr->priority == 0) &&
|
|
((hdr->flow_lbl[0] & 0xF0) == 0)) {
|
|
/* compress (elide) all */
|
|
iphc0 |= LOWPAN_IPHC_TC_C;
|
|
} else {
|
|
/* compress only the flow label */
|
|
*hc_ptr = tmp;
|
|
hc_ptr += 1;
|
|
}
|
|
} else {
|
|
/* Flow label cannot be compressed */
|
|
if ((hdr->priority == 0) &&
|
|
((hdr->flow_lbl[0] & 0xF0) == 0)) {
|
|
/* compress only traffic class */
|
|
iphc0 |= LOWPAN_IPHC_TC_C;
|
|
*hc_ptr = (tmp & 0xc0) | (hdr->flow_lbl[0] & 0x0F);
|
|
memcpy(hc_ptr + 1, &hdr->flow_lbl[1], 2);
|
|
hc_ptr += 3;
|
|
} else {
|
|
/* compress nothing */
|
|
memcpy(hc_ptr, hdr, 4);
|
|
/* replace the top byte with new ECN | DSCP format */
|
|
*hc_ptr = tmp;
|
|
hc_ptr += 4;
|
|
}
|
|
}
|
|
|
|
/* NOTE: payload length is always compressed */
|
|
|
|
/* Check if we provide the nhc format for nexthdr and compression
|
|
* functionality. If not nexthdr is handled inline and not compressed.
|
|
*/
|
|
ret = lowpan_nhc_check_compression(skb, hdr, &hc_ptr, &iphc0);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
/* Hop limit
|
|
* if 1: compress, encoding is 01
|
|
* if 64: compress, encoding is 10
|
|
* if 255: compress, encoding is 11
|
|
* else do not compress
|
|
*/
|
|
switch (hdr->hop_limit) {
|
|
case 1:
|
|
iphc0 |= LOWPAN_IPHC_TTL_1;
|
|
break;
|
|
case 64:
|
|
iphc0 |= LOWPAN_IPHC_TTL_64;
|
|
break;
|
|
case 255:
|
|
iphc0 |= LOWPAN_IPHC_TTL_255;
|
|
break;
|
|
default:
|
|
lowpan_push_hc_data(&hc_ptr, &hdr->hop_limit,
|
|
sizeof(hdr->hop_limit));
|
|
}
|
|
|
|
addr_type = ipv6_addr_type(&hdr->saddr);
|
|
/* source address compression */
|
|
if (addr_type == IPV6_ADDR_ANY) {
|
|
pr_debug("source address is unspecified, setting SAC\n");
|
|
iphc1 |= LOWPAN_IPHC_SAC;
|
|
} else {
|
|
if (addr_type & IPV6_ADDR_LINKLOCAL) {
|
|
iphc1 |= lowpan_compress_addr_64(&hc_ptr,
|
|
LOWPAN_IPHC_SAM_BIT,
|
|
&hdr->saddr, saddr);
|
|
pr_debug("source address unicast link-local %pI6c iphc1 0x%02x\n",
|
|
&hdr->saddr, iphc1);
|
|
} else {
|
|
pr_debug("send the full source address\n");
|
|
lowpan_push_hc_data(&hc_ptr, hdr->saddr.s6_addr, 16);
|
|
}
|
|
}
|
|
|
|
addr_type = ipv6_addr_type(&hdr->daddr);
|
|
/* destination address compression */
|
|
if (addr_type & IPV6_ADDR_MULTICAST) {
|
|
pr_debug("destination address is multicast: ");
|
|
iphc1 |= LOWPAN_IPHC_M;
|
|
if (lowpan_is_mcast_addr_compressable8(&hdr->daddr)) {
|
|
pr_debug("compressed to 1 octet\n");
|
|
iphc1 |= LOWPAN_IPHC_DAM_11;
|
|
/* use last byte */
|
|
lowpan_push_hc_data(&hc_ptr,
|
|
&hdr->daddr.s6_addr[15], 1);
|
|
} else if (lowpan_is_mcast_addr_compressable32(&hdr->daddr)) {
|
|
pr_debug("compressed to 4 octets\n");
|
|
iphc1 |= LOWPAN_IPHC_DAM_10;
|
|
/* second byte + the last three */
|
|
lowpan_push_hc_data(&hc_ptr,
|
|
&hdr->daddr.s6_addr[1], 1);
|
|
lowpan_push_hc_data(&hc_ptr,
|
|
&hdr->daddr.s6_addr[13], 3);
|
|
} else if (lowpan_is_mcast_addr_compressable48(&hdr->daddr)) {
|
|
pr_debug("compressed to 6 octets\n");
|
|
iphc1 |= LOWPAN_IPHC_DAM_01;
|
|
/* second byte + the last five */
|
|
lowpan_push_hc_data(&hc_ptr,
|
|
&hdr->daddr.s6_addr[1], 1);
|
|
lowpan_push_hc_data(&hc_ptr,
|
|
&hdr->daddr.s6_addr[11], 5);
|
|
} else {
|
|
pr_debug("using full address\n");
|
|
iphc1 |= LOWPAN_IPHC_DAM_00;
|
|
lowpan_push_hc_data(&hc_ptr, hdr->daddr.s6_addr, 16);
|
|
}
|
|
} else {
|
|
if (addr_type & IPV6_ADDR_LINKLOCAL) {
|
|
/* TODO: context lookup */
|
|
iphc1 |= lowpan_compress_addr_64(&hc_ptr,
|
|
LOWPAN_IPHC_DAM_BIT, &hdr->daddr, daddr);
|
|
pr_debug("dest address unicast link-local %pI6c "
|
|
"iphc1 0x%02x\n", &hdr->daddr, iphc1);
|
|
} else {
|
|
pr_debug("dest address unicast %pI6c\n", &hdr->daddr);
|
|
lowpan_push_hc_data(&hc_ptr, hdr->daddr.s6_addr, 16);
|
|
}
|
|
}
|
|
|
|
/* next header compression */
|
|
if (iphc0 & LOWPAN_IPHC_NH_C) {
|
|
ret = lowpan_nhc_do_compression(skb, hdr, &hc_ptr);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
|
|
head[0] = iphc0;
|
|
head[1] = iphc1;
|
|
|
|
skb_pull(skb, sizeof(struct ipv6hdr));
|
|
skb_reset_transport_header(skb);
|
|
memcpy(skb_push(skb, hc_ptr - head), head, hc_ptr - head);
|
|
skb_reset_network_header(skb);
|
|
|
|
pr_debug("header len %d skb %u\n", (int)(hc_ptr - head), skb->len);
|
|
|
|
raw_dump_table(__func__, "raw skb data dump compressed",
|
|
skb->data, skb->len);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(lowpan_header_compress);
|