summaryrefslogtreecommitdiff
path: root/include/net/6lowpan.h
blob: cf3bc564ac033f76773e9c6ec12599df1776da8e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
/*
 * 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 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)

#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_priv) + llpriv_size)

enum lowpan_lltypes {
	LOWPAN_LLTYPE_BTLE,
	LOWPAN_LLTYPE_IEEE802154,
};

struct lowpan_priv {
	enum lowpan_lltypes lltype;

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

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

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;
}

#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;
}

void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype);

/**
 * 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__ */