xref: /openbmc/linux/include/net/6lowpan.h (revision 1b69c6d0ae90b7f1a4f61d5c8209d5cb7a55f849)
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 
56 #include <net/ipv6.h>
57 #include <net/net_namespace.h>
58 
59 #define UIP_802154_SHORTADDR_LEN	2  /* compressed ipv6 address length */
60 #define UIP_IPH_LEN			40 /* ipv6 fixed header size */
61 #define UIP_PROTO_UDP			17 /* ipv6 next header value for UDP */
62 #define UIP_FRAGH_LEN			8  /* ipv6 fragment header size */
63 
64 /*
65  * ipv6 address based on mac
66  * second bit-flip (Universe/Local) is done according RFC2464
67  */
68 #define is_addr_mac_addr_based(a, m) \
69 	((((a)->s6_addr[8])  == (((m)[0]) ^ 0x02)) &&	\
70 	 (((a)->s6_addr[9])  == (m)[1]) &&		\
71 	 (((a)->s6_addr[10]) == (m)[2]) &&		\
72 	 (((a)->s6_addr[11]) == (m)[3]) &&		\
73 	 (((a)->s6_addr[12]) == (m)[4]) &&		\
74 	 (((a)->s6_addr[13]) == (m)[5]) &&		\
75 	 (((a)->s6_addr[14]) == (m)[6]) &&		\
76 	 (((a)->s6_addr[15]) == (m)[7]))
77 
78 /*
79  * check whether we can compress the IID to 16 bits,
80  * it's possible for unicast adresses with first 49 bits are zero only.
81  */
82 #define lowpan_is_iid_16_bit_compressable(a)	\
83 	((((a)->s6_addr16[4]) == 0) &&		\
84 	 (((a)->s6_addr[10]) == 0) &&		\
85 	 (((a)->s6_addr[11]) == 0xff) &&	\
86 	 (((a)->s6_addr[12]) == 0xfe) &&	\
87 	 (((a)->s6_addr[13]) == 0))
88 
89 /* check whether the 112-bit gid of the multicast address is mappable to: */
90 
91 /* 48 bits, FFXX::00XX:XXXX:XXXX */
92 #define lowpan_is_mcast_addr_compressable48(a)	\
93 	((((a)->s6_addr16[1]) == 0) &&		\
94 	 (((a)->s6_addr16[2]) == 0) &&		\
95 	 (((a)->s6_addr16[3]) == 0) &&		\
96 	 (((a)->s6_addr16[4]) == 0) &&		\
97 	 (((a)->s6_addr[10]) == 0))
98 
99 /* 32 bits, FFXX::00XX:XXXX */
100 #define lowpan_is_mcast_addr_compressable32(a)	\
101 	((((a)->s6_addr16[1]) == 0) &&		\
102 	 (((a)->s6_addr16[2]) == 0) &&		\
103 	 (((a)->s6_addr16[3]) == 0) &&		\
104 	 (((a)->s6_addr16[4]) == 0) &&		\
105 	 (((a)->s6_addr16[5]) == 0) &&		\
106 	 (((a)->s6_addr[12]) == 0))
107 
108 /* 8 bits, FF02::00XX */
109 #define lowpan_is_mcast_addr_compressable8(a)	\
110 	((((a)->s6_addr[1])  == 2) &&		\
111 	 (((a)->s6_addr16[1]) == 0) &&		\
112 	 (((a)->s6_addr16[2]) == 0) &&		\
113 	 (((a)->s6_addr16[3]) == 0) &&		\
114 	 (((a)->s6_addr16[4]) == 0) &&		\
115 	 (((a)->s6_addr16[5]) == 0) &&		\
116 	 (((a)->s6_addr16[6]) == 0) &&		\
117 	 (((a)->s6_addr[14]) == 0))
118 
119 #define lowpan_is_addr_broadcast(a)	\
120 	((((a)[0]) == 0xFF) &&	\
121 	 (((a)[1]) == 0xFF) &&	\
122 	 (((a)[2]) == 0xFF) &&	\
123 	 (((a)[3]) == 0xFF) &&	\
124 	 (((a)[4]) == 0xFF) &&	\
125 	 (((a)[5]) == 0xFF) &&	\
126 	 (((a)[6]) == 0xFF) &&	\
127 	 (((a)[7]) == 0xFF))
128 
129 #define LOWPAN_DISPATCH_IPV6		0x41 /* 01000001 = 65 */
130 #define LOWPAN_DISPATCH_IPHC		0x60 /* 011xxxxx = ... */
131 #define LOWPAN_DISPATCH_IPHC_MASK	0xe0
132 
133 static inline bool lowpan_is_ipv6(u8 dispatch)
134 {
135 	return dispatch == LOWPAN_DISPATCH_IPV6;
136 }
137 
138 static inline bool lowpan_is_iphc(u8 dispatch)
139 {
140 	return (dispatch & LOWPAN_DISPATCH_IPHC_MASK) == LOWPAN_DISPATCH_IPHC;
141 }
142 
143 #define LOWPAN_FRAG_TIMEOUT	(HZ * 60)	/* time-out 60 sec */
144 
145 #define LOWPAN_FRAG1_HEAD_SIZE	0x4
146 #define LOWPAN_FRAGN_HEAD_SIZE	0x5
147 
148 /*
149  * Values of fields within the IPHC encoding first byte
150  * (C stands for compressed and I for inline)
151  */
152 #define LOWPAN_IPHC_TF		0x18
153 
154 #define LOWPAN_IPHC_FL_C	0x10
155 #define LOWPAN_IPHC_TC_C	0x08
156 #define LOWPAN_IPHC_NH_C	0x04
157 #define LOWPAN_IPHC_TTL_1	0x01
158 #define LOWPAN_IPHC_TTL_64	0x02
159 #define LOWPAN_IPHC_TTL_255	0x03
160 #define LOWPAN_IPHC_TTL_I	0x00
161 
162 
163 /* Values of fields within the IPHC encoding second byte */
164 #define LOWPAN_IPHC_CID		0x80
165 
166 #define LOWPAN_IPHC_ADDR_00	0x00
167 #define LOWPAN_IPHC_ADDR_01	0x01
168 #define LOWPAN_IPHC_ADDR_02	0x02
169 #define LOWPAN_IPHC_ADDR_03	0x03
170 
171 #define LOWPAN_IPHC_SAC		0x40
172 #define LOWPAN_IPHC_SAM		0x30
173 
174 #define LOWPAN_IPHC_SAM_BIT	4
175 
176 #define LOWPAN_IPHC_M		0x08
177 #define LOWPAN_IPHC_DAC		0x04
178 #define LOWPAN_IPHC_DAM_00	0x00
179 #define LOWPAN_IPHC_DAM_01	0x01
180 #define LOWPAN_IPHC_DAM_10	0x02
181 #define LOWPAN_IPHC_DAM_11	0x03
182 
183 #define LOWPAN_IPHC_DAM_BIT	0
184 /*
185  * LOWPAN_UDP encoding (works together with IPHC)
186  */
187 #define LOWPAN_NHC_UDP_MASK		0xF8
188 #define LOWPAN_NHC_UDP_ID		0xF0
189 #define LOWPAN_NHC_UDP_CHECKSUMC	0x04
190 #define LOWPAN_NHC_UDP_CHECKSUMI	0x00
191 
192 #define LOWPAN_NHC_UDP_4BIT_PORT	0xF0B0
193 #define LOWPAN_NHC_UDP_4BIT_MASK	0xFFF0
194 #define LOWPAN_NHC_UDP_8BIT_PORT	0xF000
195 #define LOWPAN_NHC_UDP_8BIT_MASK	0xFF00
196 
197 /* values for port compression, _with checksum_ ie bit 5 set to 0 */
198 #define LOWPAN_NHC_UDP_CS_P_00	0xF0 /* all inline */
199 #define LOWPAN_NHC_UDP_CS_P_01	0xF1 /* source 16bit inline,
200 					dest = 0xF0 + 8 bit inline */
201 #define LOWPAN_NHC_UDP_CS_P_10	0xF2 /* source = 0xF0 + 8bit inline,
202 					dest = 16 bit inline */
203 #define LOWPAN_NHC_UDP_CS_P_11	0xF3 /* source & dest = 0xF0B + 4bit inline */
204 #define LOWPAN_NHC_UDP_CS_C	0x04 /* checksum elided */
205 
206 #define LOWPAN_PRIV_SIZE(llpriv_size)	\
207 	(sizeof(struct lowpan_priv) + llpriv_size)
208 
209 enum lowpan_lltypes {
210 	LOWPAN_LLTYPE_BTLE,
211 	LOWPAN_LLTYPE_IEEE802154,
212 };
213 
214 struct lowpan_priv {
215 	enum lowpan_lltypes lltype;
216 
217 	/* must be last */
218 	u8 priv[0] __aligned(sizeof(void *));
219 };
220 
221 static inline
222 struct lowpan_priv *lowpan_priv(const struct net_device *dev)
223 {
224 	return netdev_priv(dev);
225 }
226 
227 struct lowpan_802154_cb {
228 	u16 d_tag;
229 	unsigned int d_size;
230 	u8 d_offset;
231 };
232 
233 static inline
234 struct lowpan_802154_cb *lowpan_802154_cb(const struct sk_buff *skb)
235 {
236 	BUILD_BUG_ON(sizeof(struct lowpan_802154_cb) > sizeof(skb->cb));
237 	return (struct lowpan_802154_cb *)skb->cb;
238 }
239 
240 #ifdef DEBUG
241 /* print data in line */
242 static inline void raw_dump_inline(const char *caller, char *msg,
243 				   unsigned char *buf, int len)
244 {
245 	if (msg)
246 		pr_debug("%s():%s: ", caller, msg);
247 
248 	print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, buf, len, false);
249 }
250 
251 /* print data in a table format:
252  *
253  * addr: xx xx xx xx xx xx
254  * addr: xx xx xx xx xx xx
255  * ...
256  */
257 static inline void raw_dump_table(const char *caller, char *msg,
258 				  unsigned char *buf, int len)
259 {
260 	if (msg)
261 		pr_debug("%s():%s:\n", caller, msg);
262 
263 	print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET, 16, 1, buf, len, false);
264 }
265 #else
266 static inline void raw_dump_table(const char *caller, char *msg,
267 				  unsigned char *buf, int len) { }
268 static inline void raw_dump_inline(const char *caller, char *msg,
269 				   unsigned char *buf, int len) { }
270 #endif
271 
272 static inline int lowpan_fetch_skb_u8(struct sk_buff *skb, u8 *val)
273 {
274 	if (unlikely(!pskb_may_pull(skb, 1)))
275 		return -EINVAL;
276 
277 	*val = skb->data[0];
278 	skb_pull(skb, 1);
279 
280 	return 0;
281 }
282 
283 static inline bool lowpan_fetch_skb(struct sk_buff *skb,
284 		void *data, const unsigned int len)
285 {
286 	if (unlikely(!pskb_may_pull(skb, len)))
287 		return true;
288 
289 	skb_copy_from_linear_data(skb, data, len);
290 	skb_pull(skb, len);
291 
292 	return false;
293 }
294 
295 static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data,
296 				       const size_t len)
297 {
298 	memcpy(*hc_ptr, data, len);
299 	*hc_ptr += len;
300 }
301 
302 void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype);
303 
304 int
305 lowpan_header_decompress(struct sk_buff *skb, struct net_device *dev,
306 			 const u8 *saddr, const u8 saddr_type,
307 			 const u8 saddr_len, const u8 *daddr,
308 			 const u8 daddr_type, const u8 daddr_len,
309 			 u8 iphc0, u8 iphc1);
310 int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev,
311 			unsigned short type, const void *_daddr,
312 			const void *_saddr, unsigned int len);
313 
314 #endif /* __6LOWPAN_H__ */
315