[mirror_ubuntu-hirsute-kernel.git] / include / net / 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__

#include <linux/debugfs.h>

#include <net/ipv6.h>
#include <net/net_namespace.h>

#define EUI64_ADDR_LEN		8

#define LOWPAN_NHC_MAX_ID_LEN	1
/* Maximum next header compression length which we currently support inclusive
 * possible inline data.
 */
#define LOWPAN_NHC_MAX_HDR_LEN	(sizeof(struct udphdr))
/* Max IPHC Header len without IPv6 hdr specific inline data.
 * Useful for getting the "extra" bytes we need at worst case compression.
 *
 * LOWPAN_IPHC + CID + LOWPAN_NHC_MAX_ID_LEN
 */
#define LOWPAN_IPHC_MAX_HEADER_LEN	(2 + 1 + LOWPAN_NHC_MAX_ID_LEN)
/* Maximum worst case IPHC header buffer size */
#define LOWPAN_IPHC_MAX_HC_BUF_LEN	(sizeof(struct ipv6hdr) +	\
					 LOWPAN_IPHC_MAX_HEADER_LEN +	\
					 LOWPAN_NHC_MAX_HDR_LEN)
/* SCI/DCI is 4 bit width, so we have maximum 16 entries */
#define LOWPAN_IPHC_CTX_TABLE_SIZE	(1 << 4)

#define LOWPAN_DISPATCH_IPV6		0x41 /* 01000001 = 65 */
#define LOWPAN_DISPATCH_IPHC		0x60 /* 011xxxxx = ... */
#define LOWPAN_DISPATCH_IPHC_MASK	0xe0

static inline bool lowpan_is_ipv6(u8 dispatch)
{
	return dispatch == LOWPAN_DISPATCH_IPV6;
}

static inline bool lowpan_is_iphc(u8 dispatch)
{
	return (dispatch & LOWPAN_DISPATCH_IPHC_MASK) == LOWPAN_DISPATCH_IPHC;
}

#define LOWPAN_PRIV_SIZE(llpriv_size)	\
	(sizeof(struct lowpan_dev) + llpriv_size)

enum lowpan_lltypes {
	LOWPAN_LLTYPE_BTLE,
	LOWPAN_LLTYPE_IEEE802154,
};

enum lowpan_iphc_ctx_flags {
	LOWPAN_IPHC_CTX_FLAG_ACTIVE,
	LOWPAN_IPHC_CTX_FLAG_COMPRESSION,
};

struct lowpan_iphc_ctx {
	u8 id;
	struct in6_addr pfx;
	u8 plen;
	unsigned long flags;
};

struct lowpan_iphc_ctx_table {
	spinlock_t lock;
	const struct lowpan_iphc_ctx_ops *ops;
	struct lowpan_iphc_ctx table[LOWPAN_IPHC_CTX_TABLE_SIZE];
};

static inline bool lowpan_iphc_ctx_is_active(const struct lowpan_iphc_ctx *ctx)
{
	return test_bit(LOWPAN_IPHC_CTX_FLAG_ACTIVE, &ctx->flags);
}

static inline bool
lowpan_iphc_ctx_is_compression(const struct lowpan_iphc_ctx *ctx)
{
	return test_bit(LOWPAN_IPHC_CTX_FLAG_COMPRESSION, &ctx->flags);
}

struct lowpan_dev {
	enum lowpan_lltypes lltype;
	struct dentry *iface_debugfs;
	struct lowpan_iphc_ctx_table ctx;

	/* must be last */
	u8 priv[0] __aligned(sizeof(void *));
};

static inline
struct lowpan_dev *lowpan_dev(const struct net_device *dev)
{
	return netdev_priv(dev);
}

/* private device info */
struct lowpan_802154_dev {
	struct net_device	*wdev; /* wpan device ptr */
	u16			fragment_tag;
};

static inline struct
lowpan_802154_dev *lowpan_802154_dev(const struct net_device *dev)
{
	return (struct lowpan_802154_dev *)lowpan_dev(dev)->priv;
}

struct lowpan_802154_cb {
	u16 d_tag;
	unsigned int d_size;
	u8 d_offset;
};

static inline
struct lowpan_802154_cb *lowpan_802154_cb(const struct sk_buff *skb)
{
	BUILD_BUG_ON(sizeof(struct lowpan_802154_cb) > sizeof(skb->cb));
	return (struct lowpan_802154_cb *)skb->cb;
}

static inline void lowpan_iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr,
						       const void *lladdr)
{
	/* fe:80::XXXX:XXXX:XXXX:XXXX
	 *        \_________________/
	 *              hwaddr
	 */
	ipaddr->s6_addr[0] = 0xFE;
	ipaddr->s6_addr[1] = 0x80;
	memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN);
	/* second bit-flip (Universe/Local)
	 * is done according RFC2464
	 */
	ipaddr->s6_addr[8] ^= 0x02;
}

#ifdef DEBUG
/* print data in line */
static inline void raw_dump_inline(const char *caller, char *msg,
				   const 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,
				  const 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,
				  const unsigned char *buf, int len) { }
static inline void raw_dump_inline(const char *caller, char *msg,
				   const unsigned char *buf, int len) { }
#endif

/**
 * lowpan_fetch_skb - getting inline data from 6LoWPAN header
 *
 * This function will pull data from sk buffer and put it into data to
 * remove the 6LoWPAN inline data. This function returns true if the
 * sk buffer is too small to pull the amount of data which is specified
 * by len.
 *
 * @skb: the buffer where the inline data should be pulled from.
 * @data: destination buffer for the inline data.
 * @len: amount of data which should be pulled in bytes.
 */
static inline bool lowpan_fetch_skb(struct sk_buff *skb, void *data,
				    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;
}

int lowpan_register_netdevice(struct net_device *dev,
			      enum lowpan_lltypes lltype);
int lowpan_register_netdev(struct net_device *dev,
			   enum lowpan_lltypes lltype);
void lowpan_unregister_netdevice(struct net_device *dev);
void lowpan_unregister_netdev(struct net_device *dev);

/**
 * lowpan_header_decompress - replace 6LoWPAN header with IPv6 header
 *
 * This function replaces the IPHC 6LoWPAN header which should be pointed at
 * skb->data and skb_network_header, with the IPv6 header.
 * It would be nice that the caller have the necessary headroom of IPv6 header
 * and greatest Transport layer header, this would reduce the overhead for
 * reallocate headroom.
 *
 * @skb: the buffer which should be manipulate.
 * @dev: the lowpan net device pointer.
 * @daddr: destination lladdr of mac header which is used for compression
 *	methods.
 * @saddr: source lladdr of mac header which is used for compression
 *	methods.
 */
int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
			     const void *daddr, const void *saddr);

/**
 * lowpan_header_compress - replace IPv6 header with 6LoWPAN header
 *
 * This function replaces the IPv6 header which should be pointed at
 * skb->data and skb_network_header, with the IPHC 6LoWPAN header.
 * The caller need to be sure that the sk buffer is not shared and at have
 * at least a headroom which is smaller or equal LOWPAN_IPHC_MAX_HEADER_LEN,
 * which is the IPHC "more bytes than IPv6 header" at worst case.
 *
 * @skb: the buffer which should be manipulate.
 * @dev: the lowpan net device pointer.
 * @daddr: destination lladdr of mac header which is used for compression
 *	methods.
 * @saddr: source lladdr of mac header which is used for compression
 *	methods.
 */
int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
			   const void *daddr, const void *saddr);

#endif /* __6LOWPAN_H__ */
Commit	Line	Data
44331fe2 AS	1	/*
	2	* Copyright 2011, Siemens AG
	3	* written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
	4	*/
	5
	6	/*
	7	* Based on patches from Jon Smirl <jonsmirl@gmail.com>
	8	* Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License version 2
	12	* as published by the Free Software Foundation.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License along
	20	* with this program; if not, write to the Free Software Foundation, Inc.,
	21	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	22	*/
	23
	24	/* Jon's code is based on 6lowpan implementation for Contiki which is:
	25	* Copyright (c) 2008, Swedish Institute of Computer Science.
	26	* All rights reserved.
	27	*
	28	* Redistribution and use in source and binary forms, with or without
	29	* modification, are permitted provided that the following conditions
	30	* are met:
	31	* 1. Redistributions of source code must retain the above copyright
	32	* notice, this list of conditions and the following disclaimer.
	33	* 2. Redistributions in binary form must reproduce the above copyright
	34	* notice, this list of conditions and the following disclaimer in the
	35	* documentation and/or other materials provided with the distribution.
	36	* 3. Neither the name of the Institute nor the names of its contributors
	37	* may be used to endorse or promote products derived from this software
	38	* without specific prior written permission.
	39	*
	40	* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
	41	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	42	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	43	* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
	44	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	45	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	46	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	47	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	48	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	49	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	50	* SUCH DAMAGE.
	51	*/
	52
	53	#ifndef __6LOWPAN_H__
	54	#define __6LOWPAN_H__
	55
b1815fd9 AA	56	#include <linux/debugfs.h>
b1815fd9 AA	57
91c69227	58	#include <net/ipv6.h>
17d8ecb8	59	#include <net/net_namespace.h>
91c69227	60
4d6a6aed AA	61	#define EUI64_ADDR_LEN 8
4d6a6aed AA	62
87a93e4e	63	#define LOWPAN_NHC_MAX_ID_LEN 1
bf513fd6 AA	64	/* Maximum next header compression length which we currently support inclusive
	65	* possible inline data.
	66	*/
	67	#define LOWPAN_NHC_MAX_HDR_LEN (sizeof(struct udphdr))
87a93e4e AA	68	/* Max IPHC Header len without IPv6 hdr specific inline data.
	69	* Useful for getting the "extra" bytes we need at worst case compression.
	70	*
	71	* LOWPAN_IPHC + CID + LOWPAN_NHC_MAX_ID_LEN
	72	*/
	73	#define LOWPAN_IPHC_MAX_HEADER_LEN (2 + 1 + LOWPAN_NHC_MAX_ID_LEN)
bf513fd6 AA	74	/* Maximum worst case IPHC header buffer size */
	75	#define LOWPAN_IPHC_MAX_HC_BUF_LEN (sizeof(struct ipv6hdr) + \
	76	LOWPAN_IPHC_MAX_HEADER_LEN + \
	77	LOWPAN_NHC_MAX_HDR_LEN)
5609c185 AA	78	/* SCI/DCI is 4 bit width, so we have maximum 16 entries */
5609c185 AA	79	#define LOWPAN_IPHC_CTX_TABLE_SIZE (1 << 4)
87a93e4e	80
72a5e6bb AA	81	#define LOWPAN_DISPATCH_IPV6 0x41 /* 01000001 = 65 */
	82	#define LOWPAN_DISPATCH_IPHC 0x60 /* 011xxxxx = ... */
	83	#define LOWPAN_DISPATCH_IPHC_MASK 0xe0
44331fe2	84
72a5e6bb AA	85	static inline bool lowpan_is_ipv6(u8 dispatch)
	86	{
	87	return dispatch == LOWPAN_DISPATCH_IPV6;
	88	}
	89
	90	static inline bool lowpan_is_iphc(u8 dispatch)
	91	{
	92	return (dispatch & LOWPAN_DISPATCH_IPHC_MASK) == LOWPAN_DISPATCH_IPHC;
	93	}
719269af	94
b72f6f51	95	#define LOWPAN_PRIV_SIZE(llpriv_size) \
2e4d60cb	96	(sizeof(struct lowpan_dev) + llpriv_size)
b72f6f51 AA	97
	98	enum lowpan_lltypes {
	99	LOWPAN_LLTYPE_BTLE,
	100	LOWPAN_LLTYPE_IEEE802154,
	101	};
	102
5609c185 AA	103	enum lowpan_iphc_ctx_flags {
	104	LOWPAN_IPHC_CTX_FLAG_ACTIVE,
	105	LOWPAN_IPHC_CTX_FLAG_COMPRESSION,
	106	};
	107
	108	struct lowpan_iphc_ctx {
	109	u8 id;
	110	struct in6_addr pfx;
	111	u8 plen;
	112	unsigned long flags;
	113	};
	114
	115	struct lowpan_iphc_ctx_table {
	116	spinlock_t lock;
	117	const struct lowpan_iphc_ctx_ops *ops;
	118	struct lowpan_iphc_ctx table[LOWPAN_IPHC_CTX_TABLE_SIZE];
	119	};
	120
	121	static inline bool lowpan_iphc_ctx_is_active(const struct lowpan_iphc_ctx *ctx)
	122	{
	123	return test_bit(LOWPAN_IPHC_CTX_FLAG_ACTIVE, &ctx->flags);
	124	}
	125
	126	static inline bool
	127	lowpan_iphc_ctx_is_compression(const struct lowpan_iphc_ctx *ctx)
	128	{
	129	return test_bit(LOWPAN_IPHC_CTX_FLAG_COMPRESSION, &ctx->flags);
	130	}
	131
2e4d60cb	132	struct lowpan_dev {
b72f6f51	133	enum lowpan_lltypes lltype;
b1815fd9	134	struct dentry *iface_debugfs;
5609c185	135	struct lowpan_iphc_ctx_table ctx;
b72f6f51 AA	136
	137	/* must be last */
	138	u8 priv[0] __aligned(sizeof(void *));
	139	};
	140
	141	static inline
2e4d60cb	142	struct lowpan_dev lowpan_dev(const struct net_device dev)
b72f6f51 AA	143	{
	144	return netdev_priv(dev);
	145	}
	146
353c224e AA	147	/* private device info */
	148	struct lowpan_802154_dev {
	149	struct net_device wdev; / wpan device ptr */
	150	u16 fragment_tag;
	151	};
	152
	153	static inline struct
	154	lowpan_802154_dev lowpan_802154_dev(const struct net_device dev)
	155	{
	156	return (struct lowpan_802154_dev *)lowpan_dev(dev)->priv;
	157	}
	158
72a5e6bb AA	159	struct lowpan_802154_cb {
	160	u16 d_tag;
	161	unsigned int d_size;
	162	u8 d_offset;
	163	};
	164
	165	static inline
	166	struct lowpan_802154_cb lowpan_802154_cb(const struct sk_buff skb)
	167	{
	168	BUILD_BUG_ON(sizeof(struct lowpan_802154_cb) > sizeof(skb->cb));
	169	return (struct lowpan_802154_cb *)skb->cb;
	170	}
	171
a5862f2a AA	172	static inline void lowpan_iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr,
	173	const void *lladdr)
	174	{
	175	/* fe:80::XXXX:XXXX:XXXX:XXXX
	176	* \_________________/
	177	* hwaddr
	178	*/
	179	ipaddr->s6_addr[0] = 0xFE;
	180	ipaddr->s6_addr[1] = 0x80;
	181	memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN);
	182	/* second bit-flip (Universe/Local)
	183	* is done according RFC2464
	184	*/
	185	ipaddr->s6_addr[8] ^= 0x02;
	186	}
	187
841a5ec7 AA	188	#ifdef DEBUG
	189	/* print data in line */
	190	static inline void raw_dump_inline(const char caller, char msg,
a6f77389	191	const unsigned char *buf, int len)
841a5ec7 AA	192	{
	193	if (msg)
	194	pr_debug("%s():%s: ", caller, msg);
	195
	196	print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, buf, len, false);
	197	}
	198
	199	/* print data in a table format:
	200	*
	201	* addr: xx xx xx xx xx xx
	202	* addr: xx xx xx xx xx xx
	203	* ...
	204	*/
	205	static inline void raw_dump_table(const char caller, char msg,
a6f77389	206	const unsigned char *buf, int len)
841a5ec7 AA	207	{
	208	if (msg)
	209	pr_debug("%s():%s:\n", caller, msg);
	210
	211	print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET, 16, 1, buf, len, false);
	212	}
	213	#else
	214	static inline void raw_dump_table(const char caller, char msg,
a6f77389	215	const unsigned char *buf, int len) { }
841a5ec7	216	static inline void raw_dump_inline(const char caller, char msg,
a6f77389	217	const unsigned char *buf, int len) { }
841a5ec7 AA	218	#endif
841a5ec7 AA	219
478208e3 AA	220	/**
	221	* lowpan_fetch_skb - getting inline data from 6LoWPAN header
	222	*
	223	* This function will pull data from sk buffer and put it into data to
	224	* remove the 6LoWPAN inline data. This function returns true if the
	225	* sk buffer is too small to pull the amount of data which is specified
	226	* by len.
	227	*
	228	* @skb: the buffer where the inline data should be pulled from.
	229	* @data: destination buffer for the inline data.
	230	* @len: amount of data which should be pulled in bytes.
	231	*/
	232	static inline bool lowpan_fetch_skb(struct sk_buff skb, void data,
	233	unsigned int len)
4666669f AA	234	{
	235	if (unlikely(!pskb_may_pull(skb, len)))
	236	return true;
	237
	238	skb_copy_from_linear_data(skb, data, len);
	239	skb_pull(skb, len);
	240
	241	return false;
	242	}
	243
3109f2e2 AA	244	static inline void lowpan_push_hc_data(u8 *hc_ptr, const void data,
	245	const size_t len)
	246	{
	247	memcpy(*hc_ptr, data, len);
	248	*hc_ptr += len;
	249	}
	250
00f59314 AA	251	int lowpan_register_netdevice(struct net_device *dev,
	252	enum lowpan_lltypes lltype);
	253	int lowpan_register_netdev(struct net_device *dev,
	254	enum lowpan_lltypes lltype);
	255	void lowpan_unregister_netdevice(struct net_device *dev);
	256	void lowpan_unregister_netdev(struct net_device *dev);
b72f6f51	257
8911d774 AA	258	/**
	259	* lowpan_header_decompress - replace 6LoWPAN header with IPv6 header
	260	*
	261	* This function replaces the IPHC 6LoWPAN header which should be pointed at
	262	* skb->data and skb_network_header, with the IPv6 header.
	263	* It would be nice that the caller have the necessary headroom of IPv6 header
	264	* and greatest Transport layer header, this would reduce the overhead for
	265	* reallocate headroom.
	266	*
	267	* @skb: the buffer which should be manipulate.
	268	* @dev: the lowpan net device pointer.
	269	* @daddr: destination lladdr of mac header which is used for compression
	270	* methods.
	271	* @saddr: source lladdr of mac header which is used for compression
	272	* methods.
	273	*/
	274	int lowpan_header_decompress(struct sk_buff skb, const struct net_device dev,
	275	const void daddr, const void saddr);
a6f77389 AA	276
	277	/**
	278	* lowpan_header_compress - replace IPv6 header with 6LoWPAN header
	279	*
	280	* This function replaces the IPv6 header which should be pointed at
	281	* skb->data and skb_network_header, with the IPHC 6LoWPAN header.
	282	* The caller need to be sure that the sk buffer is not shared and at have
	283	* at least a headroom which is smaller or equal LOWPAN_IPHC_MAX_HEADER_LEN,
	284	* which is the IPHC "more bytes than IPv6 header" at worst case.
	285	*
	286	* @skb: the buffer which should be manipulate.
	287	* @dev: the lowpan net device pointer.
	288	* @daddr: destination lladdr of mac header which is used for compression
	289	* methods.
	290	* @saddr: source lladdr of mac header which is used for compression
	291	* methods.
	292	*/
	293	int lowpan_header_compress(struct sk_buff skb, const struct net_device dev,
	294	const void daddr, const void saddr);
8df8c56a	295
44331fe2	296	#endif /* __6LOWPAN_H__ */