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Jukka Rissanen8df8c562013-12-11 17:05:34 +02001/*
2 * Copyright 2011, Siemens AG
3 * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
4 */
5
Varka Bhadram4710d802014-07-02 09:01:09 +05306/* Based on patches from Jon Smirl <jonsmirl@gmail.com>
Jukka Rissanen8df8c562013-12-11 17:05:34 +02007 * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
Jukka Rissanen8df8c562013-12-11 17:05:34 +020018 */
19
20/* Jon's code is based on 6lowpan implementation for Contiki which is:
21 * Copyright (c) 2008, Swedish Institute of Computer Science.
22 * All rights reserved.
23 *
24 * Redistribution and use in source and binary forms, with or without
25 * modification, are permitted provided that the following conditions
26 * are met:
27 * 1. Redistributions of source code must retain the above copyright
28 * notice, this list of conditions and the following disclaimer.
29 * 2. Redistributions in binary form must reproduce the above copyright
30 * notice, this list of conditions and the following disclaimer in the
31 * documentation and/or other materials provided with the distribution.
32 * 3. Neither the name of the Institute nor the names of its contributors
33 * may be used to endorse or promote products derived from this software
34 * without specific prior written permission.
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
37 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
39 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
40 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
41 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
42 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
44 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
45 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46 * SUCH DAMAGE.
47 */
48
49#include <linux/bitops.h>
50#include <linux/if_arp.h>
51#include <linux/netdevice.h>
Alexander Aring8911d772015-10-13 13:42:58 +020052
Alexander Aringcefc8c82014-03-05 14:29:05 +010053#include <net/6lowpan.h>
Jukka Rissanen8df8c562013-12-11 17:05:34 +020054#include <net/ipv6.h>
Alexander Aring8911d772015-10-13 13:42:58 +020055
56/* special link-layer handling */
57#include <net/mac802154.h>
Jukka Rissanen8df8c562013-12-11 17:05:34 +020058
Alexander Aringcc6ed262015-01-09 16:42:58 +010059#include "nhc.h"
60
Alexander Aringc8a3e7e2015-10-20 08:31:24 +020061/* Values of fields within the IPHC encoding first byte */
62#define LOWPAN_IPHC_TF_MASK 0x18
63#define LOWPAN_IPHC_TF_00 0x00
64#define LOWPAN_IPHC_TF_01 0x08
65#define LOWPAN_IPHC_TF_10 0x10
66#define LOWPAN_IPHC_TF_11 0x18
Alexander Aring63500472015-10-20 08:31:22 +020067
Alexander Aringc8a3e7e2015-10-20 08:31:24 +020068#define LOWPAN_IPHC_NH 0x04
69
70#define LOWPAN_IPHC_HLIM_MASK 0x03
71#define LOWPAN_IPHC_HLIM_00 0x00
72#define LOWPAN_IPHC_HLIM_01 0x01
73#define LOWPAN_IPHC_HLIM_10 0x02
74#define LOWPAN_IPHC_HLIM_11 0x03
Alexander Aring63500472015-10-20 08:31:22 +020075
76/* Values of fields within the IPHC encoding second byte */
77#define LOWPAN_IPHC_CID 0x80
78
Alexander Aring63500472015-10-20 08:31:22 +020079#define LOWPAN_IPHC_SAC 0x40
Alexander Aring63500472015-10-20 08:31:22 +020080
Alexander Aringc8a3e7e2015-10-20 08:31:24 +020081#define LOWPAN_IPHC_SAM_MASK 0x30
82#define LOWPAN_IPHC_SAM_00 0x00
83#define LOWPAN_IPHC_SAM_01 0x10
84#define LOWPAN_IPHC_SAM_10 0x20
85#define LOWPAN_IPHC_SAM_11 0x30
Alexander Aring63500472015-10-20 08:31:22 +020086
87#define LOWPAN_IPHC_M 0x08
Alexander Aringc8a3e7e2015-10-20 08:31:24 +020088
Alexander Aring63500472015-10-20 08:31:22 +020089#define LOWPAN_IPHC_DAC 0x04
Alexander Aringc8a3e7e2015-10-20 08:31:24 +020090
91#define LOWPAN_IPHC_DAM_MASK 0x03
Alexander Aring63500472015-10-20 08:31:22 +020092#define LOWPAN_IPHC_DAM_00 0x00
93#define LOWPAN_IPHC_DAM_01 0x01
94#define LOWPAN_IPHC_DAM_10 0x02
95#define LOWPAN_IPHC_DAM_11 0x03
96
Alexander Aring63500472015-10-20 08:31:22 +020097/* ipv6 address based on mac
98 * second bit-flip (Universe/Local) is done according RFC2464
99 */
100#define is_addr_mac_addr_based(a, m) \
101 ((((a)->s6_addr[8]) == (((m)[0]) ^ 0x02)) && \
102 (((a)->s6_addr[9]) == (m)[1]) && \
103 (((a)->s6_addr[10]) == (m)[2]) && \
104 (((a)->s6_addr[11]) == (m)[3]) && \
105 (((a)->s6_addr[12]) == (m)[4]) && \
106 (((a)->s6_addr[13]) == (m)[5]) && \
107 (((a)->s6_addr[14]) == (m)[6]) && \
108 (((a)->s6_addr[15]) == (m)[7]))
109
110/* check whether we can compress the IID to 16 bits,
111 * it's possible for unicast addresses with first 49 bits are zero only.
112 */
113#define lowpan_is_iid_16_bit_compressable(a) \
114 ((((a)->s6_addr16[4]) == 0) && \
115 (((a)->s6_addr[10]) == 0) && \
116 (((a)->s6_addr[11]) == 0xff) && \
117 (((a)->s6_addr[12]) == 0xfe) && \
118 (((a)->s6_addr[13]) == 0))
119
120/* check whether the 112-bit gid of the multicast address is mappable to: */
121
122/* 48 bits, FFXX::00XX:XXXX:XXXX */
123#define lowpan_is_mcast_addr_compressable48(a) \
124 ((((a)->s6_addr16[1]) == 0) && \
125 (((a)->s6_addr16[2]) == 0) && \
126 (((a)->s6_addr16[3]) == 0) && \
127 (((a)->s6_addr16[4]) == 0) && \
128 (((a)->s6_addr[10]) == 0))
129
130/* 32 bits, FFXX::00XX:XXXX */
131#define lowpan_is_mcast_addr_compressable32(a) \
132 ((((a)->s6_addr16[1]) == 0) && \
133 (((a)->s6_addr16[2]) == 0) && \
134 (((a)->s6_addr16[3]) == 0) && \
135 (((a)->s6_addr16[4]) == 0) && \
136 (((a)->s6_addr16[5]) == 0) && \
137 (((a)->s6_addr[12]) == 0))
138
139/* 8 bits, FF02::00XX */
140#define lowpan_is_mcast_addr_compressable8(a) \
141 ((((a)->s6_addr[1]) == 2) && \
142 (((a)->s6_addr16[1]) == 0) && \
143 (((a)->s6_addr16[2]) == 0) && \
144 (((a)->s6_addr16[3]) == 0) && \
145 (((a)->s6_addr16[4]) == 0) && \
146 (((a)->s6_addr16[5]) == 0) && \
147 (((a)->s6_addr16[6]) == 0) && \
148 (((a)->s6_addr[14]) == 0))
149
Alexander Aring8911d772015-10-13 13:42:58 +0200150static inline void iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr,
151 const void *lladdr)
152{
153 /* fe:80::XXXX:XXXX:XXXX:XXXX
154 * \_________________/
155 * hwaddr
156 */
157 ipaddr->s6_addr[0] = 0xFE;
158 ipaddr->s6_addr[1] = 0x80;
159 memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN);
160 /* second bit-flip (Universe/Local)
161 * is done according RFC2464
162 */
163 ipaddr->s6_addr[8] ^= 0x02;
164}
165
166static inline void iphc_uncompress_802154_lladdr(struct in6_addr *ipaddr,
167 const void *lladdr)
168{
169 const struct ieee802154_addr *addr = lladdr;
170 u8 eui64[EUI64_ADDR_LEN] = { };
171
172 switch (addr->mode) {
173 case IEEE802154_ADDR_LONG:
174 ieee802154_le64_to_be64(eui64, &addr->extended_addr);
175 iphc_uncompress_eui64_lladdr(ipaddr, eui64);
176 break;
177 case IEEE802154_ADDR_SHORT:
178 /* fe:80::ff:fe00:XXXX
179 * \__/
180 * short_addr
181 *
182 * Universe/Local bit is zero.
183 */
184 ipaddr->s6_addr[0] = 0xFE;
185 ipaddr->s6_addr[1] = 0x80;
186 ipaddr->s6_addr[11] = 0xFF;
187 ipaddr->s6_addr[12] = 0xFE;
188 ieee802154_le16_to_be16(&ipaddr->s6_addr16[7],
189 &addr->short_addr);
190 break;
191 default:
192 /* should never handled and filtered by 802154 6lowpan */
193 WARN_ON_ONCE(1);
194 break;
195 }
196}
197
Varka Bhadram4710d802014-07-02 09:01:09 +0530198/* Uncompress address function for source and
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200199 * destination address(non-multicast).
200 *
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200201 * address_mode is the masked value for sam or dam value
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200202 */
Alexander Aring8911d772015-10-13 13:42:58 +0200203static int uncompress_addr(struct sk_buff *skb, const struct net_device *dev,
204 struct in6_addr *ipaddr, u8 address_mode,
205 const void *lladdr)
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200206{
207 bool fail;
208
209 switch (address_mode) {
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200210 /* SAM and DAM are the same here */
211 case LOWPAN_IPHC_DAM_00:
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200212 /* for global link addresses */
213 fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16);
214 break;
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200215 case LOWPAN_IPHC_SAM_01:
216 case LOWPAN_IPHC_DAM_01:
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200217 /* fe:80::XXXX:XXXX:XXXX:XXXX */
218 ipaddr->s6_addr[0] = 0xFE;
219 ipaddr->s6_addr[1] = 0x80;
220 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8);
221 break;
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200222 case LOWPAN_IPHC_SAM_10:
223 case LOWPAN_IPHC_DAM_10:
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200224 /* fe:80::ff:fe00:XXXX */
225 ipaddr->s6_addr[0] = 0xFE;
226 ipaddr->s6_addr[1] = 0x80;
227 ipaddr->s6_addr[11] = 0xFF;
228 ipaddr->s6_addr[12] = 0xFE;
229 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2);
230 break;
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200231 case LOWPAN_IPHC_SAM_11:
232 case LOWPAN_IPHC_DAM_11:
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200233 fail = false;
Alexander Aring8911d772015-10-13 13:42:58 +0200234 switch (lowpan_priv(dev)->lltype) {
235 case LOWPAN_LLTYPE_IEEE802154:
236 iphc_uncompress_802154_lladdr(ipaddr, lladdr);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200237 break;
238 default:
Alexander Aring8911d772015-10-13 13:42:58 +0200239 iphc_uncompress_eui64_lladdr(ipaddr, lladdr);
240 break;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200241 }
242 break;
243 default:
244 pr_debug("Invalid address mode value: 0x%x\n", address_mode);
245 return -EINVAL;
246 }
247
248 if (fail) {
249 pr_debug("Failed to fetch skb data\n");
250 return -EIO;
251 }
252
253 raw_dump_inline(NULL, "Reconstructed ipv6 addr is",
254 ipaddr->s6_addr, 16);
255
256 return 0;
257}
258
Varka Bhadram4710d802014-07-02 09:01:09 +0530259/* Uncompress address function for source context
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200260 * based address(non-multicast).
261 */
262static int uncompress_context_based_src_addr(struct sk_buff *skb,
Varka Bhadram4710d802014-07-02 09:01:09 +0530263 struct in6_addr *ipaddr,
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200264 u8 address_mode)
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200265{
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200266 switch (address_mode) {
267 case LOWPAN_IPHC_SAM_00:
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200268 /* unspec address ::
269 * Do nothing, address is already ::
270 */
271 break;
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200272 case LOWPAN_IPHC_SAM_01:
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200273 /* TODO */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200274 case LOWPAN_IPHC_SAM_10:
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200275 /* TODO */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200276 case LOWPAN_IPHC_SAM_11:
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200277 /* TODO */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200278 netdev_warn(skb->dev, "SAM value 0x%x not supported\n",
279 address_mode);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200280 return -EINVAL;
281 default:
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200282 pr_debug("Invalid sam value: 0x%x\n", address_mode);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200283 return -EINVAL;
284 }
285
286 raw_dump_inline(NULL,
287 "Reconstructed context based ipv6 src addr is",
288 ipaddr->s6_addr, 16);
289
290 return 0;
291}
292
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200293/* Uncompress function for multicast destination address,
294 * when M bit is set.
295 */
Marcel Holtmann7fc4cfd2014-07-30 03:48:41 +0200296static int lowpan_uncompress_multicast_daddr(struct sk_buff *skb,
297 struct in6_addr *ipaddr,
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200298 u8 address_mode)
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200299{
300 bool fail;
301
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200302 switch (address_mode) {
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200303 case LOWPAN_IPHC_DAM_00:
304 /* 00: 128 bits. The full address
305 * is carried in-line.
306 */
307 fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16);
308 break;
309 case LOWPAN_IPHC_DAM_01:
310 /* 01: 48 bits. The address takes
311 * the form ffXX::00XX:XXXX:XXXX.
312 */
313 ipaddr->s6_addr[0] = 0xFF;
314 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1);
315 fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[11], 5);
316 break;
317 case LOWPAN_IPHC_DAM_10:
318 /* 10: 32 bits. The address takes
319 * the form ffXX::00XX:XXXX.
320 */
321 ipaddr->s6_addr[0] = 0xFF;
322 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1);
323 fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[13], 3);
324 break;
325 case LOWPAN_IPHC_DAM_11:
326 /* 11: 8 bits. The address takes
327 * the form ff02::00XX.
328 */
329 ipaddr->s6_addr[0] = 0xFF;
330 ipaddr->s6_addr[1] = 0x02;
331 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[15], 1);
332 break;
333 default:
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200334 pr_debug("DAM value has a wrong value: 0x%x\n", address_mode);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200335 return -EINVAL;
336 }
337
338 if (fail) {
339 pr_debug("Failed to fetch skb data\n");
340 return -EIO;
341 }
342
343 raw_dump_inline(NULL, "Reconstructed ipv6 multicast addr is",
Marcel Holtmann7fc4cfd2014-07-30 03:48:41 +0200344 ipaddr->s6_addr, 16);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200345
346 return 0;
347}
348
Alexander Aringb5af9bd2015-10-20 08:31:25 +0200349/* get the ecn values from iphc tf format and set it to ipv6hdr */
350static inline void lowpan_iphc_tf_set_ecn(struct ipv6hdr *hdr, const u8 *tf)
351{
352 /* get the two higher bits which is ecn */
353 u8 ecn = tf[0] & 0xc0;
354
355 /* ECN takes 0x30 in hdr->flow_lbl[0] */
356 hdr->flow_lbl[0] |= (ecn >> 2);
357}
358
359/* get the dscp values from iphc tf format and set it to ipv6hdr */
360static inline void lowpan_iphc_tf_set_dscp(struct ipv6hdr *hdr, const u8 *tf)
361{
362 /* DSCP is at place after ECN */
363 u8 dscp = tf[0] & 0x3f;
364
365 /* The four highest bits need to be set at hdr->priority */
366 hdr->priority |= ((dscp & 0x3c) >> 2);
367 /* The two lower bits is part of hdr->flow_lbl[0] */
368 hdr->flow_lbl[0] |= ((dscp & 0x03) << 6);
369}
370
371/* get the flow label values from iphc tf format and set it to ipv6hdr */
372static inline void lowpan_iphc_tf_set_lbl(struct ipv6hdr *hdr, const u8 *lbl)
373{
374 /* flow label is always some array started with lower nibble of
375 * flow_lbl[0] and followed with two bytes afterwards. Inside inline
376 * data the flow_lbl position can be different, which will be handled
377 * by lbl pointer. E.g. case "01" vs "00" the traffic class is 8 bit
378 * shifted, the different lbl pointer will handle that.
379 *
380 * The flow label will started at lower nibble of flow_lbl[0], the
381 * higher nibbles are part of DSCP + ECN.
382 */
383 hdr->flow_lbl[0] |= lbl[0] & 0x0f;
384 memcpy(&hdr->flow_lbl[1], &lbl[1], 2);
385}
386
387/* lowpan_iphc_tf_decompress - decompress the traffic class.
388 * This function will return zero on success, a value lower than zero if
389 * failed.
390 */
391static int lowpan_iphc_tf_decompress(struct sk_buff *skb, struct ipv6hdr *hdr,
392 u8 val)
393{
394 u8 tf[4];
395
396 /* Traffic Class and Flow Label */
397 switch (val) {
398 case LOWPAN_IPHC_TF_00:
399 /* ECN + DSCP + 4-bit Pad + Flow Label (4 bytes) */
400 if (lowpan_fetch_skb(skb, tf, 4))
401 return -EINVAL;
402
403 /* 1 2 3
404 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
405 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
406 * |ECN| DSCP | rsv | Flow Label |
407 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
408 */
409 lowpan_iphc_tf_set_ecn(hdr, tf);
410 lowpan_iphc_tf_set_dscp(hdr, tf);
411 lowpan_iphc_tf_set_lbl(hdr, &tf[1]);
412 break;
413 case LOWPAN_IPHC_TF_01:
414 /* ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided. */
415 if (lowpan_fetch_skb(skb, tf, 3))
416 return -EINVAL;
417
418 /* 1 2
419 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
420 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
421 * |ECN|rsv| Flow Label |
422 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
423 */
424 lowpan_iphc_tf_set_ecn(hdr, tf);
425 lowpan_iphc_tf_set_lbl(hdr, &tf[0]);
426 break;
427 case LOWPAN_IPHC_TF_10:
428 /* ECN + DSCP (1 byte), Flow Label is elided. */
429 if (lowpan_fetch_skb(skb, tf, 1))
430 return -EINVAL;
431
432 /* 0 1 2 3 4 5 6 7
433 * +-+-+-+-+-+-+-+-+
434 * |ECN| DSCP |
435 * +-+-+-+-+-+-+-+-+
436 */
437 lowpan_iphc_tf_set_ecn(hdr, tf);
438 lowpan_iphc_tf_set_dscp(hdr, tf);
439 break;
440 case LOWPAN_IPHC_TF_11:
441 /* Traffic Class and Flow Label are elided */
442 break;
443 default:
444 WARN_ON_ONCE(1);
445 return -EINVAL;
446 }
447
448 return 0;
449}
450
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200451/* TTL uncompression values */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200452static const u8 lowpan_ttl_values[] = {
453 [LOWPAN_IPHC_HLIM_01] = 1,
454 [LOWPAN_IPHC_HLIM_10] = 64,
455 [LOWPAN_IPHC_HLIM_11] = 255,
456};
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200457
Alexander Aring8911d772015-10-13 13:42:58 +0200458int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
459 const void *daddr, const void *saddr)
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200460{
461 struct ipv6hdr hdr = {};
Alexander Aringb5af9bd2015-10-20 08:31:25 +0200462 u8 iphc0, iphc1;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200463 int err;
464
465 raw_dump_table(__func__, "raw skb data dump uncompressed",
Varka Bhadram4710d802014-07-02 09:01:09 +0530466 skb->data, skb->len);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200467
Alexander Aring478208e2015-10-13 13:42:59 +0200468 if (lowpan_fetch_skb(skb, &iphc0, sizeof(iphc0)) ||
469 lowpan_fetch_skb(skb, &iphc1, sizeof(iphc1)))
Alexander Aring8911d772015-10-13 13:42:58 +0200470 return -EINVAL;
471
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200472 /* another if the CID flag is set */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200473 if (iphc1 & LOWPAN_IPHC_CID)
474 return -ENOTSUPP;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200475
476 hdr.version = 6;
477
Alexander Aringb5af9bd2015-10-20 08:31:25 +0200478 err = lowpan_iphc_tf_decompress(skb, &hdr,
479 iphc0 & LOWPAN_IPHC_TF_MASK);
480 if (err < 0)
481 return err;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200482
483 /* Next Header */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200484 if (!(iphc0 & LOWPAN_IPHC_NH)) {
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200485 /* Next header is carried inline */
Alexander Aring4ebc9602014-07-29 23:47:00 +0200486 if (lowpan_fetch_skb(skb, &hdr.nexthdr, sizeof(hdr.nexthdr)))
Martin Townsend56b2c3e2014-11-06 19:15:13 +0000487 return -EINVAL;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200488
489 pr_debug("NH flag is set, next header carried inline: %02x\n",
490 hdr.nexthdr);
491 }
492
493 /* Hop Limit */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200494 if ((iphc0 & LOWPAN_IPHC_HLIM_MASK) != LOWPAN_IPHC_HLIM_00) {
495 hdr.hop_limit = lowpan_ttl_values[iphc0 & LOWPAN_IPHC_HLIM_MASK];
Varka Bhadram4710d802014-07-02 09:01:09 +0530496 } else {
Alexander Aring4ebc9602014-07-29 23:47:00 +0200497 if (lowpan_fetch_skb(skb, &hdr.hop_limit,
498 sizeof(hdr.hop_limit)))
Martin Townsend56b2c3e2014-11-06 19:15:13 +0000499 return -EINVAL;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200500 }
501
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200502 if (iphc1 & LOWPAN_IPHC_SAC) {
503 /* Source address context based uncompression */
504 pr_debug("SAC bit is set. Handle context based source address.\n");
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200505 err = uncompress_context_based_src_addr(skb, &hdr.saddr,
506 iphc1 & LOWPAN_IPHC_SAM_MASK);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200507 } else {
508 /* Source address uncompression */
509 pr_debug("source address stateless compression\n");
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200510 err = uncompress_addr(skb, dev, &hdr.saddr,
511 iphc1 & LOWPAN_IPHC_SAM_MASK, saddr);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200512 }
513
514 /* Check on error of previous branch */
515 if (err)
Martin Townsend56b2c3e2014-11-06 19:15:13 +0000516 return -EINVAL;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200517
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200518 /* check for Multicast Compression */
519 if (iphc1 & LOWPAN_IPHC_M) {
520 if (iphc1 & LOWPAN_IPHC_DAC) {
521 pr_debug("dest: context-based mcast compression\n");
522 /* TODO: implement this */
523 } else {
Marcel Holtmann7fc4cfd2014-07-30 03:48:41 +0200524 err = lowpan_uncompress_multicast_daddr(skb, &hdr.daddr,
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200525 iphc1 & LOWPAN_IPHC_DAM_MASK);
Marcel Holtmann7fc4cfd2014-07-30 03:48:41 +0200526
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200527 if (err)
Martin Townsend56b2c3e2014-11-06 19:15:13 +0000528 return -EINVAL;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200529 }
530 } else {
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200531 err = uncompress_addr(skb, dev, &hdr.daddr,
532 iphc1 & LOWPAN_IPHC_DAM_MASK, daddr);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200533 pr_debug("dest: stateless compression mode %d dest %pI6c\n",
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200534 iphc1 & LOWPAN_IPHC_DAM_MASK, &hdr.daddr);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200535 if (err)
Martin Townsend56b2c3e2014-11-06 19:15:13 +0000536 return -EINVAL;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200537 }
538
Alexander Aringcc6ed262015-01-09 16:42:58 +0100539 /* Next header data uncompression */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200540 if (iphc0 & LOWPAN_IPHC_NH) {
Alexander Aringcc6ed262015-01-09 16:42:58 +0100541 err = lowpan_nhc_do_uncompression(skb, dev, &hdr);
542 if (err < 0)
Martin Townsend11e3ff72014-10-13 11:00:56 +0100543 return err;
Martin Townsend11e3ff72014-10-13 11:00:56 +0100544 } else {
545 err = skb_cow(skb, sizeof(hdr));
Martin Townsend56b2c3e2014-11-06 19:15:13 +0000546 if (unlikely(err))
Martin Townsend11e3ff72014-10-13 11:00:56 +0100547 return err;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200548 }
549
Alexander Aring72a5e6b2015-09-02 14:21:25 +0200550 switch (lowpan_priv(dev)->lltype) {
551 case LOWPAN_LLTYPE_IEEE802154:
552 if (lowpan_802154_cb(skb)->d_size)
553 hdr.payload_len = htons(lowpan_802154_cb(skb)->d_size -
554 sizeof(struct ipv6hdr));
555 else
556 hdr.payload_len = htons(skb->len);
557 break;
558 default:
559 hdr.payload_len = htons(skb->len);
560 break;
561 }
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200562
563 pr_debug("skb headroom size = %d, data length = %d\n",
564 skb_headroom(skb), skb->len);
565
566 pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n\t"
567 "nexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
568 hdr.version, ntohs(hdr.payload_len), hdr.nexthdr,
569 hdr.hop_limit, &hdr.daddr);
570
Martin Townsendf8b36172014-10-23 15:40:53 +0100571 skb_push(skb, sizeof(hdr));
572 skb_reset_network_header(skb);
573 skb_copy_to_linear_data(skb, &hdr, sizeof(hdr));
574
Marcel Holtmann7fc4cfd2014-07-30 03:48:41 +0200575 raw_dump_table(__func__, "raw header dump", (u8 *)&hdr, sizeof(hdr));
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200576
Martin Townsendf8b36172014-10-23 15:40:53 +0100577 return 0;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200578}
Martin Townsend01141232014-10-23 15:40:56 +0100579EXPORT_SYMBOL_GPL(lowpan_header_decompress);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200580
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200581static const u8 lowpan_iphc_dam_to_sam_value[] = {
582 [LOWPAN_IPHC_DAM_00] = LOWPAN_IPHC_SAM_00,
583 [LOWPAN_IPHC_DAM_01] = LOWPAN_IPHC_SAM_01,
584 [LOWPAN_IPHC_DAM_10] = LOWPAN_IPHC_SAM_10,
585 [LOWPAN_IPHC_DAM_11] = LOWPAN_IPHC_SAM_11,
586};
587
588static u8 lowpan_compress_addr_64(u8 **hc_ptr, const struct in6_addr *ipaddr,
589 const unsigned char *lladdr, bool sam)
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200590{
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200591 u8 dam = LOWPAN_IPHC_DAM_00;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200592
593 if (is_addr_mac_addr_based(ipaddr, lladdr)) {
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200594 dam = LOWPAN_IPHC_DAM_11; /* 0-bits */
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200595 pr_debug("address compression 0 bits\n");
596 } else if (lowpan_is_iid_16_bit_compressable(ipaddr)) {
597 /* compress IID to 16 bits xxxx::XXXX */
Alexander Aring85c71242014-07-29 23:47:01 +0200598 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[7], 2);
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200599 dam = LOWPAN_IPHC_DAM_10; /* 16-bits */
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200600 raw_dump_inline(NULL, "Compressed ipv6 addr is (16 bits)",
Alexander Aring84ca5e02014-07-29 23:46:58 +0200601 *hc_ptr - 2, 2);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200602 } else {
603 /* do not compress IID => xxxx::IID */
Alexander Aring85c71242014-07-29 23:47:01 +0200604 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[4], 8);
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200605 dam = LOWPAN_IPHC_DAM_01; /* 64-bits */
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200606 raw_dump_inline(NULL, "Compressed ipv6 addr is (64 bits)",
Alexander Aring84ca5e02014-07-29 23:46:58 +0200607 *hc_ptr - 8, 8);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200608 }
609
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200610 if (sam)
611 return lowpan_iphc_dam_to_sam_value[dam];
612 else
613 return dam;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200614}
615
Alexander Aringb5af9bd2015-10-20 08:31:25 +0200616/* lowpan_iphc_get_tc - get the ECN + DCSP fields in hc format */
617static inline u8 lowpan_iphc_get_tc(const struct ipv6hdr *hdr)
618{
619 u8 dscp, ecn;
620
621 /* hdr->priority contains the higher bits of dscp, lower are part of
622 * flow_lbl[0]. Note ECN, DCSP is swapped in ipv6 hdr.
623 */
624 dscp = (hdr->priority << 2) | ((hdr->flow_lbl[0] & 0xc0) >> 6);
625 /* ECN is at the two lower bits from first nibble of flow_lbl[0] */
626 ecn = (hdr->flow_lbl[0] & 0x30);
627 /* for pretty debug output, also shift ecn to get the ecn value */
628 pr_debug("ecn 0x%02x dscp 0x%02x\n", ecn >> 4, dscp);
629 /* ECN is at 0x30 now, shift it to have ECN + DCSP */
630 return (ecn << 2) | dscp;
631}
632
633/* lowpan_iphc_is_flow_lbl_zero - check if flow label is zero */
634static inline bool lowpan_iphc_is_flow_lbl_zero(const struct ipv6hdr *hdr)
635{
636 return ((!(hdr->flow_lbl[0] & 0x0f)) &&
637 !hdr->flow_lbl[1] && !hdr->flow_lbl[2]);
638}
639
640/* lowpan_iphc_tf_compress - compress the traffic class which is set by
641 * ipv6hdr. Return the corresponding format identifier which is used.
642 */
643static u8 lowpan_iphc_tf_compress(u8 **hc_ptr, const struct ipv6hdr *hdr)
644{
645 /* get ecn dscp data in a byteformat as: ECN(hi) + DSCP(lo) */
646 u8 tc = lowpan_iphc_get_tc(hdr), tf[4], val;
647
648 /* printout the traffic class in hc format */
649 pr_debug("tc 0x%02x\n", tc);
650
651 if (lowpan_iphc_is_flow_lbl_zero(hdr)) {
652 if (!tc) {
653 /* 11: Traffic Class and Flow Label are elided. */
654 val = LOWPAN_IPHC_TF_11;
655 } else {
656 /* 10: ECN + DSCP (1 byte), Flow Label is elided.
657 *
658 * 0 1 2 3 4 5 6 7
659 * +-+-+-+-+-+-+-+-+
660 * |ECN| DSCP |
661 * +-+-+-+-+-+-+-+-+
662 */
663 lowpan_push_hc_data(hc_ptr, &tc, sizeof(tc));
664 val = LOWPAN_IPHC_TF_10;
665 }
666 } else {
667 /* check if dscp is zero, it's after the first two bit */
668 if (!(tc & 0x3f)) {
669 /* 01: ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided
670 *
671 * 1 2
672 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
673 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
674 * |ECN|rsv| Flow Label |
675 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
676 */
677 memcpy(&tf[0], &hdr->flow_lbl[0], 3);
678 /* zero the highest 4-bits, contains DCSP + ECN */
679 tf[0] &= ~0xf0;
680 /* set ECN */
681 tf[0] |= (tc & 0xc0);
682
683 lowpan_push_hc_data(hc_ptr, tf, 3);
684 val = LOWPAN_IPHC_TF_01;
685 } else {
686 /* 00: ECN + DSCP + 4-bit Pad + Flow Label (4 bytes)
687 *
688 * 1 2 3
689 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
690 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
691 * |ECN| DSCP | rsv | Flow Label |
692 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
693 */
694 memcpy(&tf[0], &tc, sizeof(tc));
695 /* highest nibble of flow_lbl[0] is part of DSCP + ECN
696 * which will be the 4-bit pad and will be filled with
697 * zeros afterwards.
698 */
699 memcpy(&tf[1], &hdr->flow_lbl[0], 3);
700 /* zero the 4-bit pad, which is reserved */
701 tf[1] &= ~0xf0;
702
703 lowpan_push_hc_data(hc_ptr, tf, 4);
704 val = LOWPAN_IPHC_TF_00;
705 }
706 }
707
708 return val;
709}
710
Alexander Aring09bf4202015-10-20 08:31:26 +0200711static u8 lowpan_iphc_mcast_addr_compress(u8 **hc_ptr,
712 const struct in6_addr *ipaddr)
713{
714 u8 val;
715
716 if (lowpan_is_mcast_addr_compressable8(ipaddr)) {
717 pr_debug("compressed to 1 octet\n");
718 /* use last byte */
719 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[15], 1);
720 val = LOWPAN_IPHC_DAM_11;
721 } else if (lowpan_is_mcast_addr_compressable32(ipaddr)) {
722 pr_debug("compressed to 4 octets\n");
723 /* second byte + the last three */
724 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[1], 1);
725 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[13], 3);
726 val = LOWPAN_IPHC_DAM_10;
727 } else if (lowpan_is_mcast_addr_compressable48(ipaddr)) {
728 pr_debug("compressed to 6 octets\n");
729 /* second byte + the last five */
730 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[1], 1);
731 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[11], 5);
732 val = LOWPAN_IPHC_DAM_01;
733 } else {
734 pr_debug("using full address\n");
735 lowpan_push_hc_data(hc_ptr, ipaddr->s6_addr, 16);
736 val = LOWPAN_IPHC_DAM_00;
737 }
738
739 return val;
740}
741
Alexander Aringa6f77382015-10-13 13:42:57 +0200742int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
743 const void *daddr, const void *saddr)
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200744{
Alexander Aringb5af9bd2015-10-20 08:31:25 +0200745 u8 iphc0, iphc1, *hc_ptr;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200746 struct ipv6hdr *hdr;
Alexander Aringbf513fd2015-10-13 13:42:56 +0200747 u8 head[LOWPAN_IPHC_MAX_HC_BUF_LEN] = {};
Alexander Aringcc6ed262015-01-09 16:42:58 +0100748 int ret, addr_type;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200749
Alexander Aringa6f77382015-10-13 13:42:57 +0200750 if (skb->protocol != htons(ETH_P_IPV6))
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200751 return -EINVAL;
752
753 hdr = ipv6_hdr(skb);
Alexander Aring84ca5e02014-07-29 23:46:58 +0200754 hc_ptr = head + 2;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200755
756 pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n"
757 "\tnexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
Varka Bhadram4710d802014-07-02 09:01:09 +0530758 hdr->version, ntohs(hdr->payload_len), hdr->nexthdr,
759 hdr->hop_limit, &hdr->daddr);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200760
761 raw_dump_table(__func__, "raw skb network header dump",
Varka Bhadram4710d802014-07-02 09:01:09 +0530762 skb_network_header(skb), sizeof(struct ipv6hdr));
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200763
Varka Bhadram4710d802014-07-02 09:01:09 +0530764 /* As we copy some bit-length fields, in the IPHC encoding bytes,
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200765 * we sometimes use |=
766 * If the field is 0, and the current bit value in memory is 1,
767 * this does not work. We therefore reset the IPHC encoding here
768 */
769 iphc0 = LOWPAN_DISPATCH_IPHC;
770 iphc1 = 0;
771
772 /* TODO: context lookup */
773
Alexander Aringa6f77382015-10-13 13:42:57 +0200774 raw_dump_inline(__func__, "saddr", saddr, EUI64_ADDR_LEN);
775 raw_dump_inline(__func__, "daddr", daddr, EUI64_ADDR_LEN);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200776
Marcel Holtmann7fc4cfd2014-07-30 03:48:41 +0200777 raw_dump_table(__func__, "sending raw skb network uncompressed packet",
Varka Bhadram4710d802014-07-02 09:01:09 +0530778 skb->data, skb->len);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200779
Alexander Aringb5af9bd2015-10-20 08:31:25 +0200780 /* Traffic Class, Flow Label compression */
781 iphc0 |= lowpan_iphc_tf_compress(&hc_ptr, hdr);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200782
783 /* NOTE: payload length is always compressed */
784
Alexander Aringcc6ed262015-01-09 16:42:58 +0100785 /* Check if we provide the nhc format for nexthdr and compression
786 * functionality. If not nexthdr is handled inline and not compressed.
787 */
Alexander Aring607b0bd2015-10-20 08:31:21 +0200788 ret = lowpan_nhc_check_compression(skb, hdr, &hc_ptr);
789 if (ret == -ENOENT)
790 lowpan_push_hc_data(&hc_ptr, &hdr->nexthdr,
791 sizeof(hdr->nexthdr));
792 else
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200793 iphc0 |= LOWPAN_IPHC_NH;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200794
Varka Bhadram4710d802014-07-02 09:01:09 +0530795 /* Hop limit
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200796 * if 1: compress, encoding is 01
797 * if 64: compress, encoding is 10
798 * if 255: compress, encoding is 11
799 * else do not compress
800 */
801 switch (hdr->hop_limit) {
802 case 1:
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200803 iphc0 |= LOWPAN_IPHC_HLIM_01;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200804 break;
805 case 64:
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200806 iphc0 |= LOWPAN_IPHC_HLIM_10;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200807 break;
808 case 255:
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200809 iphc0 |= LOWPAN_IPHC_HLIM_11;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200810 break;
811 default:
Alexander Aring85c71242014-07-29 23:47:01 +0200812 lowpan_push_hc_data(&hc_ptr, &hdr->hop_limit,
813 sizeof(hdr->hop_limit));
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200814 }
815
Alexander Aring556a5bf2014-07-29 23:47:02 +0200816 addr_type = ipv6_addr_type(&hdr->saddr);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200817 /* source address compression */
Alexander Aring556a5bf2014-07-29 23:47:02 +0200818 if (addr_type == IPV6_ADDR_ANY) {
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200819 pr_debug("source address is unspecified, setting SAC\n");
820 iphc1 |= LOWPAN_IPHC_SAC;
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200821 } else {
Alexander Aring556a5bf2014-07-29 23:47:02 +0200822 if (addr_type & IPV6_ADDR_LINKLOCAL) {
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200823 iphc1 |= lowpan_compress_addr_64(&hc_ptr, &hdr->saddr,
824 saddr, true);
Alexander Aring556a5bf2014-07-29 23:47:02 +0200825 pr_debug("source address unicast link-local %pI6c iphc1 0x%02x\n",
826 &hdr->saddr, iphc1);
827 } else {
828 pr_debug("send the full source address\n");
829 lowpan_push_hc_data(&hc_ptr, hdr->saddr.s6_addr, 16);
830 }
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200831 }
832
Alexander Aring556a5bf2014-07-29 23:47:02 +0200833 addr_type = ipv6_addr_type(&hdr->daddr);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200834 /* destination address compression */
Alexander Aring556a5bf2014-07-29 23:47:02 +0200835 if (addr_type & IPV6_ADDR_MULTICAST) {
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200836 pr_debug("destination address is multicast: ");
837 iphc1 |= LOWPAN_IPHC_M;
Alexander Aring09bf4202015-10-20 08:31:26 +0200838 iphc1 |= lowpan_iphc_mcast_addr_compress(&hc_ptr, &hdr->daddr);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200839 } else {
Alexander Aring556a5bf2014-07-29 23:47:02 +0200840 if (addr_type & IPV6_ADDR_LINKLOCAL) {
841 /* TODO: context lookup */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200842 iphc1 |= lowpan_compress_addr_64(&hc_ptr, &hdr->daddr,
843 daddr, false);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200844 pr_debug("dest address unicast link-local %pI6c "
Marcel Holtmann7fc4cfd2014-07-30 03:48:41 +0200845 "iphc1 0x%02x\n", &hdr->daddr, iphc1);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200846 } else {
847 pr_debug("dest address unicast %pI6c\n", &hdr->daddr);
Alexander Aring85c71242014-07-29 23:47:01 +0200848 lowpan_push_hc_data(&hc_ptr, hdr->daddr.s6_addr, 16);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200849 }
850 }
851
Alexander Aringcc6ed262015-01-09 16:42:58 +0100852 /* next header compression */
Alexander Aringc8a3e7e2015-10-20 08:31:24 +0200853 if (iphc0 & LOWPAN_IPHC_NH) {
Alexander Aringcc6ed262015-01-09 16:42:58 +0100854 ret = lowpan_nhc_do_compression(skb, hdr, &hc_ptr);
855 if (ret < 0)
856 return ret;
857 }
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200858
859 head[0] = iphc0;
860 head[1] = iphc1;
861
862 skb_pull(skb, sizeof(struct ipv6hdr));
863 skb_reset_transport_header(skb);
Alexander Aring84ca5e02014-07-29 23:46:58 +0200864 memcpy(skb_push(skb, hc_ptr - head), head, hc_ptr - head);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200865 skb_reset_network_header(skb);
866
Alexander Aring84ca5e02014-07-29 23:46:58 +0200867 pr_debug("header len %d skb %u\n", (int)(hc_ptr - head), skb->len);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200868
869 raw_dump_table(__func__, "raw skb data dump compressed",
Varka Bhadram4710d802014-07-02 09:01:09 +0530870 skb->data, skb->len);
Jukka Rissanen8df8c562013-12-11 17:05:34 +0200871 return 0;
872}
873EXPORT_SYMBOL_GPL(lowpan_header_compress);