6lowpan.h
/*
* Copyright 2011, Siemens AG
* written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
*/
/*
* Based on patches from Jon Smirl <jonsmirl@gmail.com>
* Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/* Jon's code is based on 6lowpan implementation for Contiki which is:
* Copyright (c) 2008, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef __6LOWPAN_H__
#define __6LOWPAN_H__
#define UIP_802154_SHORTADDR_LEN 2 /* compressed ipv6 address length */
#define UIP_IPH_LEN 40 /* ipv6 fixed header size */
#define UIP_PROTO_UDP 17 /* ipv6 next header value for UDP */
#define UIP_FRAGH_LEN 8 /* ipv6 fragment header size */
/*
* ipv6 address based on mac
* second bit-flip (Universe/Local) is done according RFC2464
*/
#define is_addr_mac_addr_based(a, m) \
((((a)->s6_addr[8]) == (((m)[0]) ^ 0x02)) && \
(((a)->s6_addr[9]) == (m)[1]) && \
(((a)->s6_addr[10]) == (m)[2]) && \
(((a)->s6_addr[11]) == (m)[3]) && \
(((a)->s6_addr[12]) == (m)[4]) && \
(((a)->s6_addr[13]) == (m)[5]) && \
(((a)->s6_addr[14]) == (m)[6]) && \
(((a)->s6_addr[15]) == (m)[7]))
/* ipv6 address is unspecified */
#define is_addr_unspecified(a) \
((((a)->s6_addr32[0]) == 0) && \
(((a)->s6_addr32[1]) == 0) && \
(((a)->s6_addr32[2]) == 0) && \
(((a)->s6_addr32[3]) == 0))
/* compare ipv6 addresses prefixes */
#define ipaddr_prefixcmp(addr1, addr2, length) \
(memcmp(addr1, addr2, length >> 3) == 0)
/* local link, i.e. FE80::/10 */
#define is_addr_link_local(a) (((a)->s6_addr16[0]) == htons(0xFE80))
/*
* check whether we can compress the IID to 16 bits,
* it's possible for unicast adresses with first 49 bits are zero only.
*/
#define lowpan_is_iid_16_bit_compressable(a) \
((((a)->s6_addr16[4]) == 0) && \
(((a)->s6_addr[10]) == 0) && \
(((a)->s6_addr[11]) == 0xff) && \
(((a)->s6_addr[12]) == 0xfe) && \
(((a)->s6_addr[13]) == 0))
/* multicast address */
#define is_addr_mcast(a) (((a)->s6_addr[0]) == 0xFF)
/* check whether the 112-bit gid of the multicast address is mappable to: */
/* 9 bits, for FF02::1 (all nodes) and FF02::2 (all routers) addresses only. */
#define lowpan_is_mcast_addr_compressable(a) \
((((a)->s6_addr16[1]) == 0) && \
(((a)->s6_addr16[2]) == 0) && \
(((a)->s6_addr16[3]) == 0) && \
(((a)->s6_addr16[4]) == 0) && \
(((a)->s6_addr16[5]) == 0) && \
(((a)->s6_addr16[6]) == 0) && \
(((a)->s6_addr[14]) == 0) && \
((((a)->s6_addr[15]) == 1) || (((a)->s6_addr[15]) == 2)))
/* 48 bits, FFXX::00XX:XXXX:XXXX */
#define lowpan_is_mcast_addr_compressable48(a) \
((((a)->s6_addr16[1]) == 0) && \
(((a)->s6_addr16[2]) == 0) && \
(((a)->s6_addr16[3]) == 0) && \
(((a)->s6_addr16[4]) == 0) && \
(((a)->s6_addr[10]) == 0))
/* 32 bits, FFXX::00XX:XXXX */
#define lowpan_is_mcast_addr_compressable32(a) \
((((a)->s6_addr16[1]) == 0) && \
(((a)->s6_addr16[2]) == 0) && \
(((a)->s6_addr16[3]) == 0) && \
(((a)->s6_addr16[4]) == 0) && \
(((a)->s6_addr16[5]) == 0) && \
(((a)->s6_addr[12]) == 0))
/* 8 bits, FF02::00XX */
#define lowpan_is_mcast_addr_compressable8(a) \
((((a)->s6_addr[1]) == 2) && \
(((a)->s6_addr16[1]) == 0) && \
(((a)->s6_addr16[2]) == 0) && \
(((a)->s6_addr16[3]) == 0) && \
(((a)->s6_addr16[4]) == 0) && \
(((a)->s6_addr16[5]) == 0) && \
(((a)->s6_addr16[6]) == 0) && \
(((a)->s6_addr[14]) == 0))
#define lowpan_is_addr_broadcast(a) \
((((a)[0]) == 0xFF) && \
(((a)[1]) == 0xFF) && \
(((a)[2]) == 0xFF) && \
(((a)[3]) == 0xFF) && \
(((a)[4]) == 0xFF) && \
(((a)[5]) == 0xFF) && \
(((a)[6]) == 0xFF) && \
(((a)[7]) == 0xFF))
#define LOWPAN_DISPATCH_IPV6 0x41 /* 01000001 = 65 */
#define LOWPAN_DISPATCH_HC1 0x42 /* 01000010 = 66 */
#define LOWPAN_DISPATCH_IPHC 0x60 /* 011xxxxx = ... */
#define LOWPAN_DISPATCH_FRAG1 0xc0 /* 11000xxx */
#define LOWPAN_DISPATCH_FRAGN 0xe0 /* 11100xxx */
#define LOWPAN_DISPATCH_MASK 0xf8 /* 11111000 */
#define LOWPAN_FRAG_TIMEOUT (HZ * 60) /* time-out 60 sec */
#define LOWPAN_FRAG1_HEAD_SIZE 0x4
#define LOWPAN_FRAGN_HEAD_SIZE 0x5
/*
* According IEEE802.15.4 standard:
* - MTU is 127 octets
* - maximum MHR size is 37 octets
* - MFR size is 2 octets
*
* so minimal payload size that we may guarantee is:
* MTU - MHR - MFR = 88 octets
*/
#define LOWPAN_FRAG_SIZE 88
/*
* Values of fields within the IPHC encoding first byte
* (C stands for compressed and I for inline)
*/
#define LOWPAN_IPHC_TF 0x18
#define LOWPAN_IPHC_FL_C 0x10
#define LOWPAN_IPHC_TC_C 0x08
#define LOWPAN_IPHC_NH_C 0x04
#define LOWPAN_IPHC_TTL_1 0x01
#define LOWPAN_IPHC_TTL_64 0x02
#define LOWPAN_IPHC_TTL_255 0x03
#define LOWPAN_IPHC_TTL_I 0x00
/* Values of fields within the IPHC encoding second byte */
#define LOWPAN_IPHC_CID 0x80
#define LOWPAN_IPHC_ADDR_00 0x00
#define LOWPAN_IPHC_ADDR_01 0x01
#define LOWPAN_IPHC_ADDR_02 0x02
#define LOWPAN_IPHC_ADDR_03 0x03
#define LOWPAN_IPHC_SAC 0x40
#define LOWPAN_IPHC_SAM 0x30
#define LOWPAN_IPHC_SAM_BIT 4
#define LOWPAN_IPHC_M 0x08
#define LOWPAN_IPHC_DAC 0x04
#define LOWPAN_IPHC_DAM_00 0x00
#define LOWPAN_IPHC_DAM_01 0x01
#define LOWPAN_IPHC_DAM_10 0x02
#define LOWPAN_IPHC_DAM_11 0x03
#define LOWPAN_IPHC_DAM_BIT 0
/*
* LOWPAN_UDP encoding (works together with IPHC)
*/
#define LOWPAN_NHC_UDP_MASK 0xF8
#define LOWPAN_NHC_UDP_ID 0xF0
#define LOWPAN_NHC_UDP_CHECKSUMC 0x04
#define LOWPAN_NHC_UDP_CHECKSUMI 0x00
#define LOWPAN_NHC_UDP_4BIT_PORT 0xF0B0
#define LOWPAN_NHC_UDP_4BIT_MASK 0xFFF0
#define LOWPAN_NHC_UDP_8BIT_PORT 0xF000
#define LOWPAN_NHC_UDP_8BIT_MASK 0xFF00
/* values for port compression, _with checksum_ ie bit 5 set to 0 */
#define LOWPAN_NHC_UDP_CS_P_00 0xF0 /* all inline */
#define LOWPAN_NHC_UDP_CS_P_01 0xF1 /* source 16bit inline,
dest = 0xF0 + 8 bit inline */
#define LOWPAN_NHC_UDP_CS_P_10 0xF2 /* source = 0xF0 + 8bit inline,
dest = 16 bit inline */
#define LOWPAN_NHC_UDP_CS_P_11 0xF3 /* source & dest = 0xF0B + 4bit inline */
static inline bool lowpan_fetch_skb(struct sk_buff *skb,
void *data, const unsigned int len)
{
if (unlikely(!pskb_may_pull(skb, len)))
return true;
skb_copy_from_linear_data(skb, data, len);
skb_pull(skb, len);
return false;
}
#endif /* __6LOWPAN_H__ */
