/*
* 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__
#include <net/ipv6.h>
#include <net/net_namespace.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]))
/*
* 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))
/* check whether the 112-bit gid of the multicast address is mappable to: */
/* 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
/*
* 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 */
#define LOWPAN_NHC_UDP_CS_C 0x04 /* checksum elided */
#ifdef DEBUG
/* print data in line */
static inline void raw_dump_inline(const char *caller, char *msg,
unsigned char *buf, int len)
{
if (msg)
pr_debug("%s():%s: ", caller, msg);
print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, buf, len, false);
}
/* print data in a table format:
*
* addr: xx xx xx xx xx xx
* addr: xx xx xx xx xx xx
* ...
*/
static inline void raw_dump_table(const char *caller, char *msg,
unsigned char *buf, int len)
{
if (msg)
pr_debug("%s():%s:\n", caller, msg);
print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET, 16, 1, buf, len, false);
}
#else
static inline void raw_dump_table(const char *caller, char *msg,
unsigned char *buf, int len) { }
static inline void raw_dump_inline(const char *caller, char *msg,
unsigned char *buf, int len) { }
#endif
static inline int lowpan_fetch_skb_u8(struct sk_buff *skb, u8 *val)
{
if (unlikely(!pskb_may_pull(skb, 1)))
return -EINVAL;
*val = skb->data[0];
skb_pull(skb, 1);
return 0;
}
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;
}
static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data,
const size_t len)
{
memcpy(*hc_ptr, data, len);
*hc_ptr += len;
}
static inline u8 lowpan_addr_mode_size(const u8 addr_mode)
{
static const u8 addr_sizes[] = {
[LOWPAN_IPHC_ADDR_00] = 16,
[LOWPAN_IPHC_ADDR_01] = 8,
[LOWPAN_IPHC_ADDR_02] = 2,
[LOWPAN_IPHC_ADDR_03] = 0,
};
return addr_sizes[addr_mode];
}
static inline u8 lowpan_next_hdr_size(const u8 h_enc, u16 *uncomp_header)
{
u8 ret = 1;
if ((h_enc & LOWPAN_NHC_UDP_MASK) == LOWPAN_NHC_UDP_ID) {
*uncomp_header += sizeof(struct udphdr);
switch (h_enc & LOWPAN_NHC_UDP_CS_P_11) {
case LOWPAN_NHC_UDP_CS_P_00:
ret += 4;
break;
case LOWPAN_NHC_UDP_CS_P_01:
case LOWPAN_NHC_UDP_CS_P_10:
ret += 3;
break;
case LOWPAN_NHC_UDP_CS_P_11:
ret++;
break;
default:
break;
}
if (!(h_enc & LOWPAN_NHC_UDP_CS_C))
ret += 2;
}
return ret;
}
/**
* lowpan_uncompress_size - returns skb->len size with uncompressed header
* @skb: sk_buff with 6lowpan header inside
* @datagram_offset: optional to get the datagram_offset value
*
* Returns the skb->len with uncompressed header
*/
static inline u16
lowpan_uncompress_size(const struct sk_buff *skb, u16 *dgram_offset)
{
u16 ret = 2, uncomp_header = sizeof(struct ipv6hdr);
u8 iphc0, iphc1, h_enc;
iphc0 = skb_network_header(skb)[0];
iphc1 = skb_network_header(skb)[1];
switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) {
case 0:
ret += 4;
break;
case 1:
ret += 3;
break;
case 2:
ret++;
break;
default:
break;
}
if (!(iphc0 & LOWPAN_IPHC_NH_C))
ret++;
if (!(iphc0 & 0x03))
ret++;
ret += lowpan_addr_mode_size((iphc1 & LOWPAN_IPHC_SAM) >>
LOWPAN_IPHC_SAM_BIT);
if (iphc1 & LOWPAN_IPHC_M) {
switch ((iphc1 & LOWPAN_IPHC_DAM_11) >>
LOWPAN_IPHC_DAM_BIT) {
case LOWPAN_IPHC_DAM_00:
ret += 16;
break;
case LOWPAN_IPHC_DAM_01:
ret += 6;
break;
case LOWPAN_IPHC_DAM_10:
ret += 4;
break;
case LOWPAN_IPHC_DAM_11:
ret++;
break;
default:
break;
}
} else {
ret += lowpan_addr_mode_size((iphc1 & LOWPAN_IPHC_DAM_11) >>
LOWPAN_IPHC_DAM_BIT);
}
if (iphc0 & LOWPAN_IPHC_NH_C) {
h_enc = skb_network_header(skb)[ret];
ret += lowpan_next_hdr_size(h_enc, &uncomp_header);
}
if (dgram_offset)
*dgram_offset = uncomp_header;
return skb->len + uncomp_header - ret;
}
int
lowpan_header_decompress(struct sk_buff *skb, struct net_device *dev,
const u8 *saddr, const u8 saddr_type,
const u8 saddr_len, const u8 *daddr,
const u8 daddr_type, const u8 daddr_len,
u8 iphc0, u8 iphc1);
int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev,
unsigned short type, const void *_daddr,
const void *_saddr, unsigned int len);
#endif /* __6LOWPAN_H__ */