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Bluetooth: hci_uart: Add Intel/AG6xx support
[linux-2.6-block.git] / net / 6lowpan / iphc.c
CommitLineData
8df8c56a
JR		 1/*
2 * Copyright 2011, Siemens AG
3 * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
4 */
5
4710d806 6/* Based on patches from Jon Smirl <jonsmirl@gmail.com>
8df8c56a
JR		 7 * 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 *
8df8c56a
JR		 18 */
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>
8911d774 52
cefc8c8a 53#include <net/6lowpan.h>
8df8c56a 54#include <net/ipv6.h>
8911d774
AA		 55
56/* special link-layer handling */
57#include <net/mac802154.h>
8df8c56a 58
5609c185 59#include "6lowpan_i.h"
cc6ed268
AA		 60#include "nhc.h"
61
c8a3e7eb
AA		 62/* Values of fields within the IPHC encoding first byte */
63#define LOWPAN_IPHC_TF_MASK 0x18
64#define LOWPAN_IPHC_TF_00 0x00
65#define LOWPAN_IPHC_TF_01 0x08
66#define LOWPAN_IPHC_TF_10 0x10
67#define LOWPAN_IPHC_TF_11 0x18
68
69#define LOWPAN_IPHC_NH 0x04
6350047e 70
c8a3e7eb
AA		 71#define LOWPAN_IPHC_HLIM_MASK 0x03
72#define LOWPAN_IPHC_HLIM_00 0x00
73#define LOWPAN_IPHC_HLIM_01 0x01
74#define LOWPAN_IPHC_HLIM_10 0x02
75#define LOWPAN_IPHC_HLIM_11 0x03
6350047e
AA		 76
77/* Values of fields within the IPHC encoding second byte */
78#define LOWPAN_IPHC_CID 0x80
79
6350047e 80#define LOWPAN_IPHC_SAC 0x40
6350047e 81
c8a3e7eb
AA		 82#define LOWPAN_IPHC_SAM_MASK 0x30
83#define LOWPAN_IPHC_SAM_00 0x00
84#define LOWPAN_IPHC_SAM_01 0x10
85#define LOWPAN_IPHC_SAM_10 0x20
86#define LOWPAN_IPHC_SAM_11 0x30
6350047e
AA		 87
88#define LOWPAN_IPHC_M 0x08
c8a3e7eb 89
6350047e 90#define LOWPAN_IPHC_DAC 0x04
c8a3e7eb
AA		 91
92#define LOWPAN_IPHC_DAM_MASK 0x03
6350047e
AA		 93#define LOWPAN_IPHC_DAM_00 0x00
94#define LOWPAN_IPHC_DAM_01 0x01
95#define LOWPAN_IPHC_DAM_10 0x02
96#define LOWPAN_IPHC_DAM_11 0x03
97
6350047e
AA		 98/* ipv6 address based on mac
99 * second bit-flip (Universe/Local) is done according RFC2464
100 */
101#define is_addr_mac_addr_based(a, m) \
102 ((((a)->s6_addr[8]) == (((m)[0]) ^ 0x02)) && \
103 (((a)->s6_addr[9]) == (m)[1]) && \
104 (((a)->s6_addr[10]) == (m)[2]) && \
105 (((a)->s6_addr[11]) == (m)[3]) && \
106 (((a)->s6_addr[12]) == (m)[4]) && \
107 (((a)->s6_addr[13]) == (m)[5]) && \
108 (((a)->s6_addr[14]) == (m)[6]) && \
109 (((a)->s6_addr[15]) == (m)[7]))
110
111/* check whether we can compress the IID to 16 bits,
112 * it's possible for unicast addresses with first 49 bits are zero only.
113 */
114#define lowpan_is_iid_16_bit_compressable(a) \
115 ((((a)->s6_addr16[4]) == 0) && \
116 (((a)->s6_addr[10]) == 0) && \
117 (((a)->s6_addr[11]) == 0xff) && \
118 (((a)->s6_addr[12]) == 0xfe) && \
119 (((a)->s6_addr[13]) == 0))
120
121/* check whether the 112-bit gid of the multicast address is mappable to: */
122
123/* 48 bits, FFXX::00XX:XXXX:XXXX */
124#define lowpan_is_mcast_addr_compressable48(a) \
125 ((((a)->s6_addr16[1]) == 0) && \
126 (((a)->s6_addr16[2]) == 0) && \
127 (((a)->s6_addr16[3]) == 0) && \
128 (((a)->s6_addr16[4]) == 0) && \
129 (((a)->s6_addr[10]) == 0))
130
131/* 32 bits, FFXX::00XX:XXXX */
132#define lowpan_is_mcast_addr_compressable32(a) \
133 ((((a)->s6_addr16[1]) == 0) && \
134 (((a)->s6_addr16[2]) == 0) && \
135 (((a)->s6_addr16[3]) == 0) && \
136 (((a)->s6_addr16[4]) == 0) && \
137 (((a)->s6_addr16[5]) == 0) && \
138 (((a)->s6_addr[12]) == 0))
139
140/* 8 bits, FF02::00XX */
141#define lowpan_is_mcast_addr_compressable8(a) \
142 ((((a)->s6_addr[1]) == 2) && \
143 (((a)->s6_addr16[1]) == 0) && \
144 (((a)->s6_addr16[2]) == 0) && \
145 (((a)->s6_addr16[3]) == 0) && \
146 (((a)->s6_addr16[4]) == 0) && \
147 (((a)->s6_addr16[5]) == 0) && \
148 (((a)->s6_addr16[6]) == 0) && \
149 (((a)->s6_addr[14]) == 0))
150
5609c185
AA		 151#define LOWPAN_IPHC_CID_DCI(cid) (cid & 0x0f)
152#define LOWPAN_IPHC_CID_SCI(cid) ((cid & 0xf0) >> 4)
153
8911d774
AA		 154static inline void iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr,
155 const void *lladdr)
156{
157 /* fe:80::XXXX:XXXX:XXXX:XXXX
158 * \_________________/
159 * hwaddr
160 */
161 ipaddr->s6_addr[0] = 0xFE;
162 ipaddr->s6_addr[1] = 0x80;
163 memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN);
164 /* second bit-flip (Universe/Local)
165 * is done according RFC2464
166 */
167 ipaddr->s6_addr[8] ^= 0x02;
168}
169
170static inline void iphc_uncompress_802154_lladdr(struct in6_addr *ipaddr,
171 const void *lladdr)
172{
173 const struct ieee802154_addr *addr = lladdr;
174 u8 eui64[EUI64_ADDR_LEN] = { };
175
176 switch (addr->mode) {
177 case IEEE802154_ADDR_LONG:
178 ieee802154_le64_to_be64(eui64, &addr->extended_addr);
179 iphc_uncompress_eui64_lladdr(ipaddr, eui64);
180 break;
181 case IEEE802154_ADDR_SHORT:
182 /* fe:80::ff:fe00:XXXX
183 * \__/
184 * short_addr
185 *
186 * Universe/Local bit is zero.
187 */
188 ipaddr->s6_addr[0] = 0xFE;
189 ipaddr->s6_addr[1] = 0x80;
190 ipaddr->s6_addr[11] = 0xFF;
191 ipaddr->s6_addr[12] = 0xFE;
192 ieee802154_le16_to_be16(&ipaddr->s6_addr16[7],
193 &addr->short_addr);
194 break;
195 default:
196 /* should never handled and filtered by 802154 6lowpan */
197 WARN_ON_ONCE(1);
198 break;
199 }
200}
201
5609c185
AA		 202static struct lowpan_iphc_ctx *
203lowpan_iphc_ctx_get_by_id(const struct net_device *dev, u8 id)
204{
205 struct lowpan_iphc_ctx *ret = &lowpan_priv(dev)->ctx.table[id];
206
207 if (!lowpan_iphc_ctx_is_active(ret))
208 return NULL;
209
210 return ret;
211}
212
213static struct lowpan_iphc_ctx *
214lowpan_iphc_ctx_get_by_addr(const struct net_device *dev,
215 const struct in6_addr *addr)
216{
217 struct lowpan_iphc_ctx *table = lowpan_priv(dev)->ctx.table;
218 struct lowpan_iphc_ctx *ret = NULL;
219 struct in6_addr addr_pfx;
220 u8 addr_plen;
221 int i;
222
223 for (i = 0; i < LOWPAN_IPHC_CTX_TABLE_SIZE; i++) {
224 /* Check if context is valid. A context that is not valid
225 * MUST NOT be used for compression.
226 */
227 if (!lowpan_iphc_ctx_is_active(&table[i]) ||
228 !lowpan_iphc_ctx_is_compression(&table[i]))
229 continue;
230
231 ipv6_addr_prefix(&addr_pfx, addr, table[i].plen);
232
233 /* if prefix len < 64, the remaining bits until 64th bit is
234 * zero. Otherwise we use table[i]->plen.
235 */
236 if (table[i].plen < 64)
237 addr_plen = 64;
238 else
239 addr_plen = table[i].plen;
240
241 if (ipv6_prefix_equal(&addr_pfx, &table[i].pfx, addr_plen)) {
242 /* remember first match */
243 if (!ret) {
244 ret = &table[i];
245 continue;
246 }
247
248 /* get the context with longest prefix len */
249 if (table[i].plen > ret->plen)
250 ret = &table[i];
251 }
252 }
253
254 return ret;
255}
256
257static struct lowpan_iphc_ctx *
258lowpan_iphc_ctx_get_by_mcast_addr(const struct net_device *dev,
259 const struct in6_addr *addr)
260{
261 struct lowpan_iphc_ctx *table = lowpan_priv(dev)->ctx.table;
262 struct lowpan_iphc_ctx *ret = NULL;
263 struct in6_addr addr_mcast, network_pfx = {};
264 int i;
265
266 /* init mcast address with */
267 memcpy(&addr_mcast, addr, sizeof(*addr));
268
269 for (i = 0; i < LOWPAN_IPHC_CTX_TABLE_SIZE; i++) {
270 /* Check if context is valid. A context that is not valid
271 * MUST NOT be used for compression.
272 */
273 if (!lowpan_iphc_ctx_is_active(&table[i]) ||
274 !lowpan_iphc_ctx_is_compression(&table[i]))
275 continue;
276
277 /* setting plen */
278 addr_mcast.s6_addr[3] = table[i].plen;
279 /* get network prefix to copy into multicast address */
280 ipv6_addr_prefix(&network_pfx, &table[i].pfx,
281 table[i].plen);
282 /* setting network prefix */
283 memcpy(&addr_mcast.s6_addr[4], &network_pfx, 8);
284
285 if (ipv6_addr_equal(addr, &addr_mcast)) {
286 ret = &table[i];
287 break;
288 }
289 }
290
291 return ret;
292}
293
4710d806 294/* Uncompress address function for source and
8df8c56a
JR		 295 * destination address(non-multicast).
296 *
c8a3e7eb 297 * address_mode is the masked value for sam or dam value
8df8c56a 298 */
8911d774
AA		 299static int uncompress_addr(struct sk_buff *skb, const struct net_device *dev,
300 struct in6_addr *ipaddr, u8 address_mode,
301 const void *lladdr)
8df8c56a
JR		 302{
303 bool fail;
304
305 switch (address_mode) {
c8a3e7eb
AA		 306 /* SAM and DAM are the same here */
307 case LOWPAN_IPHC_DAM_00:
8df8c56a
JR		 308 /* for global link addresses */
309 fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16);
310 break;
c8a3e7eb
AA		 311 case LOWPAN_IPHC_SAM_01:
312 case LOWPAN_IPHC_DAM_01:
8df8c56a
JR		 313 /* fe:80::XXXX:XXXX:XXXX:XXXX */
314 ipaddr->s6_addr[0] = 0xFE;
315 ipaddr->s6_addr[1] = 0x80;
316 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8);
317 break;
c8a3e7eb
AA		 318 case LOWPAN_IPHC_SAM_10:
319 case LOWPAN_IPHC_DAM_10:
8df8c56a
JR		 320 /* fe:80::ff:fe00:XXXX */
321 ipaddr->s6_addr[0] = 0xFE;
322 ipaddr->s6_addr[1] = 0x80;
323 ipaddr->s6_addr[11] = 0xFF;
324 ipaddr->s6_addr[12] = 0xFE;
325 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2);
326 break;
c8a3e7eb
AA		 327 case LOWPAN_IPHC_SAM_11:
328 case LOWPAN_IPHC_DAM_11:
8df8c56a 329 fail = false;
8911d774
AA		 330 switch (lowpan_priv(dev)->lltype) {
331 case LOWPAN_LLTYPE_IEEE802154:
332 iphc_uncompress_802154_lladdr(ipaddr, lladdr);
8df8c56a
JR		 333 break;
334 default:
8911d774
AA		 335 iphc_uncompress_eui64_lladdr(ipaddr, lladdr);
336 break;
8df8c56a
JR		 337 }
338 break;
339 default:
340 pr_debug("Invalid address mode value: 0x%x\n", address_mode);
341 return -EINVAL;
342 }
343
344 if (fail) {
345 pr_debug("Failed to fetch skb data\n");
346 return -EIO;
347 }
348
349 raw_dump_inline(NULL, "Reconstructed ipv6 addr is",
350 ipaddr->s6_addr, 16);
351
352 return 0;
353}
354
4710d806 355/* Uncompress address function for source context
8df8c56a
JR		 356 * based address(non-multicast).
357 */
5609c185
AA		 358static int uncompress_ctx_addr(struct sk_buff *skb,
359 const struct net_device *dev,
360 const struct lowpan_iphc_ctx *ctx,
361 struct in6_addr *ipaddr, u8 address_mode,
362 const void *lladdr)
8df8c56a 363{
5609c185
AA		 364 bool fail;
365
c8a3e7eb 366 switch (address_mode) {
5609c185
AA		 367 /* SAM and DAM are the same here */
368 case LOWPAN_IPHC_DAM_00:
369 fail = false;
370 /* SAM_00 -> unspec address ::
8df8c56a 371 * Do nothing, address is already ::
5609c185
AA		 372 *
373 * DAM 00 -> reserved should never occur.
8df8c56a
JR		 374 */
375 break;
c8a3e7eb 376 case LOWPAN_IPHC_SAM_01:
5609c185
AA		 377 case LOWPAN_IPHC_DAM_01:
378 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8);
379 ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen);
380 break;
c8a3e7eb 381 case LOWPAN_IPHC_SAM_10:
5609c185
AA		 382 case LOWPAN_IPHC_DAM_10:
383 ipaddr->s6_addr[11] = 0xFF;
384 ipaddr->s6_addr[12] = 0xFE;
385 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2);
386 ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen);
387 break;
c8a3e7eb 388 case LOWPAN_IPHC_SAM_11:
5609c185
AA		 389 case LOWPAN_IPHC_DAM_11:
390 fail = false;
391 switch (lowpan_priv(dev)->lltype) {
392 case LOWPAN_LLTYPE_IEEE802154:
393 iphc_uncompress_802154_lladdr(ipaddr, lladdr);
394 break;
395 default:
396 iphc_uncompress_eui64_lladdr(ipaddr, lladdr);
397 break;
398 }
399 ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen);
400 break;
8df8c56a 401 default:
c8a3e7eb 402 pr_debug("Invalid sam value: 0x%x\n", address_mode);
8df8c56a
JR		 403 return -EINVAL;
404 }
405
5609c185
AA		 406 if (fail) {
407 pr_debug("Failed to fetch skb data\n");
408 return -EIO;
409 }
410
8df8c56a
JR		 411 raw_dump_inline(NULL,
412 "Reconstructed context based ipv6 src addr is",
413 ipaddr->s6_addr, 16);
414
415 return 0;
416}
417
8df8c56a
JR		 418/* Uncompress function for multicast destination address,
419 * when M bit is set.
420 */
7fc4cfda
MH		 421static int lowpan_uncompress_multicast_daddr(struct sk_buff *skb,
422 struct in6_addr *ipaddr,
c8a3e7eb 423 u8 address_mode)
8df8c56a
JR		 424{
425 bool fail;
426
c8a3e7eb 427 switch (address_mode) {
8df8c56a
JR		 428 case LOWPAN_IPHC_DAM_00:
429 /* 00: 128 bits. The full address
430 * is carried in-line.
431 */
432 fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16);
433 break;
434 case LOWPAN_IPHC_DAM_01:
435 /* 01: 48 bits. The address takes
436 * the form ffXX::00XX:XXXX:XXXX.
437 */
438 ipaddr->s6_addr[0] = 0xFF;
439 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1);
440 fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[11], 5);
441 break;
442 case LOWPAN_IPHC_DAM_10:
443 /* 10: 32 bits. The address takes
444 * the form ffXX::00XX:XXXX.
445 */
446 ipaddr->s6_addr[0] = 0xFF;
447 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1);
448 fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[13], 3);
449 break;
450 case LOWPAN_IPHC_DAM_11:
451 /* 11: 8 bits. The address takes
452 * the form ff02::00XX.
453 */
454 ipaddr->s6_addr[0] = 0xFF;
455 ipaddr->s6_addr[1] = 0x02;
456 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[15], 1);
457 break;
458 default:
c8a3e7eb 459 pr_debug("DAM value has a wrong value: 0x%x\n", address_mode);
8df8c56a
JR		 460 return -EINVAL;
461 }
462
463 if (fail) {
464 pr_debug("Failed to fetch skb data\n");
465 return -EIO;
466 }
467
468 raw_dump_inline(NULL, "Reconstructed ipv6 multicast addr is",
7fc4cfda 469 ipaddr->s6_addr, 16);
8df8c56a
JR		 470
471 return 0;
472}
473
5609c185
AA		 474static int lowpan_uncompress_multicast_ctx_daddr(struct sk_buff *skb,
475 struct lowpan_iphc_ctx *ctx,
476 struct in6_addr *ipaddr,
477 u8 address_mode)
478{
479 struct in6_addr network_pfx = {};
480 bool fail;
481
482 ipaddr->s6_addr[0] = 0xFF;
483 fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 2);
484 fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[12], 4);
4c23d874 485 if (fail)
5609c185
AA		 486 return -EIO;
487
488 /* take prefix_len and network prefix from the context */
489 ipaddr->s6_addr[3] = ctx->plen;
490 /* get network prefix to copy into multicast address */
491 ipv6_addr_prefix(&network_pfx, &ctx->pfx, ctx->plen);
492 /* setting network prefix */
493 memcpy(&ipaddr->s6_addr[4], &network_pfx, 8);
494
495 return 0;
496}
497
b5af9bdb
AA		 498/* get the ecn values from iphc tf format and set it to ipv6hdr */
499static inline void lowpan_iphc_tf_set_ecn(struct ipv6hdr *hdr, const u8 *tf)
500{
501 /* get the two higher bits which is ecn */
502 u8 ecn = tf[0] & 0xc0;
503
504 /* ECN takes 0x30 in hdr->flow_lbl[0] */
505 hdr->flow_lbl[0] |= (ecn >> 2);
506}
507
508/* get the dscp values from iphc tf format and set it to ipv6hdr */
509static inline void lowpan_iphc_tf_set_dscp(struct ipv6hdr *hdr, const u8 *tf)
510{
511 /* DSCP is at place after ECN */
512 u8 dscp = tf[0] & 0x3f;
513
514 /* The four highest bits need to be set at hdr->priority */
515 hdr->priority |= ((dscp & 0x3c) >> 2);
516 /* The two lower bits is part of hdr->flow_lbl[0] */
517 hdr->flow_lbl[0] |= ((dscp & 0x03) << 6);
518}
519
520/* get the flow label values from iphc tf format and set it to ipv6hdr */
521static inline void lowpan_iphc_tf_set_lbl(struct ipv6hdr *hdr, const u8 *lbl)
522{
523 /* flow label is always some array started with lower nibble of
524 * flow_lbl[0] and followed with two bytes afterwards. Inside inline
525 * data the flow_lbl position can be different, which will be handled
526 * by lbl pointer. E.g. case "01" vs "00" the traffic class is 8 bit
527 * shifted, the different lbl pointer will handle that.
528 *
529 * The flow label will started at lower nibble of flow_lbl[0], the
530 * higher nibbles are part of DSCP + ECN.
531 */
532 hdr->flow_lbl[0] |= lbl[0] & 0x0f;
533 memcpy(&hdr->flow_lbl[1], &lbl[1], 2);
534}
535
536/* lowpan_iphc_tf_decompress - decompress the traffic class.
537 * This function will return zero on success, a value lower than zero if
538 * failed.
539 */
540static int lowpan_iphc_tf_decompress(struct sk_buff *skb, struct ipv6hdr *hdr,
541 u8 val)
542{
543 u8 tf[4];
544
545 /* Traffic Class and Flow Label */
546 switch (val) {
547 case LOWPAN_IPHC_TF_00:
548 /* ECN + DSCP + 4-bit Pad + Flow Label (4 bytes) */
549 if (lowpan_fetch_skb(skb, tf, 4))
550 return -EINVAL;
551
552 /* 1 2 3
553 * 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
554 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
555 * |ECN| DSCP | rsv | Flow Label |
556 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
557 */
558 lowpan_iphc_tf_set_ecn(hdr, tf);
559 lowpan_iphc_tf_set_dscp(hdr, tf);
560 lowpan_iphc_tf_set_lbl(hdr, &tf[1]);
561 break;
562 case LOWPAN_IPHC_TF_01:
563 /* ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided. */
564 if (lowpan_fetch_skb(skb, tf, 3))
565 return -EINVAL;
566
567 /* 1 2
568 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
569 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
570 * |ECN|rsv| Flow Label |
571 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
572 */
573 lowpan_iphc_tf_set_ecn(hdr, tf);
574 lowpan_iphc_tf_set_lbl(hdr, &tf[0]);
575 break;
576 case LOWPAN_IPHC_TF_10:
577 /* ECN + DSCP (1 byte), Flow Label is elided. */
578 if (lowpan_fetch_skb(skb, tf, 1))
579 return -EINVAL;
580
581 /* 0 1 2 3 4 5 6 7
582 * +-+-+-+-+-+-+-+-+
583 * |ECN| DSCP |
584 * +-+-+-+-+-+-+-+-+
585 */
586 lowpan_iphc_tf_set_ecn(hdr, tf);
587 lowpan_iphc_tf_set_dscp(hdr, tf);
588 break;
589 case LOWPAN_IPHC_TF_11:
590 /* Traffic Class and Flow Label are elided */
591 break;
592 default:
593 WARN_ON_ONCE(1);
594 return -EINVAL;
595 }
596
597 return 0;
598}
599
8df8c56a 600/* TTL uncompression values */
c8a3e7eb
AA		 601static const u8 lowpan_ttl_values[] = {
602 [LOWPAN_IPHC_HLIM_01] = 1,
603 [LOWPAN_IPHC_HLIM_10] = 64,
604 [LOWPAN_IPHC_HLIM_11] = 255,
605};
8df8c56a 606
8911d774
AA		 607int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev,
608 const void *daddr, const void *saddr)
8df8c56a
JR		 609{
610 struct ipv6hdr hdr = {};
5609c185
AA		 611 struct lowpan_iphc_ctx *ci;
612 u8 iphc0, iphc1, cid = 0;
8df8c56a
JR		 613 int err;
614
615 raw_dump_table(__func__, "raw skb data dump uncompressed",
4710d806 616 skb->data, skb->len);
8df8c56a 617
478208e3
AA		 618 if (lowpan_fetch_skb(skb, &iphc0, sizeof(iphc0)) ||
619 lowpan_fetch_skb(skb, &iphc1, sizeof(iphc1)))
8911d774
AA		 620 return -EINVAL;
621
8df8c56a
JR		 622 hdr.version = 6;
623
5609c185
AA		 624 /* default CID = 0, another if the CID flag is set */
625 if (iphc1 & LOWPAN_IPHC_CID) {
626 if (lowpan_fetch_skb(skb, &cid, sizeof(cid)))
627 return -EINVAL;
628 }
629
b5af9bdb
AA		 630 err = lowpan_iphc_tf_decompress(skb, &hdr,
631 iphc0 & LOWPAN_IPHC_TF_MASK);
632 if (err < 0)
633 return err;
8df8c56a
JR		 634
635 /* Next Header */
c8a3e7eb 636 if (!(iphc0 & LOWPAN_IPHC_NH)) {
8df8c56a 637 /* Next header is carried inline */
4ebc960f 638 if (lowpan_fetch_skb(skb, &hdr.nexthdr, sizeof(hdr.nexthdr)))
56b2c3ee 639 return -EINVAL;
8df8c56a
JR		 640
641 pr_debug("NH flag is set, next header carried inline: %02x\n",
642 hdr.nexthdr);
643 }
644
645 /* Hop Limit */
c8a3e7eb
AA		 646 if ((iphc0 & LOWPAN_IPHC_HLIM_MASK) != LOWPAN_IPHC_HLIM_00) {
647 hdr.hop_limit = lowpan_ttl_values[iphc0 & LOWPAN_IPHC_HLIM_MASK];
4710d806 648 } else {
4ebc960f
AA		 649 if (lowpan_fetch_skb(skb, &hdr.hop_limit,
650 sizeof(hdr.hop_limit)))
56b2c3ee 651 return -EINVAL;
8df8c56a
JR		 652 }
653
8df8c56a 654 if (iphc1 & LOWPAN_IPHC_SAC) {
5609c185
AA		 655 spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
656 ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_SCI(cid));
657 if (!ci) {
658 spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
659 return -EINVAL;
660 }
661
8df8c56a 662 pr_debug("SAC bit is set. Handle context based source address.\n");
5609c185
AA		 663 err = uncompress_ctx_addr(skb, dev, ci, &hdr.saddr,
664 iphc1 & LOWPAN_IPHC_SAM_MASK, saddr);
665 spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
8df8c56a
JR		 666 } else {
667 /* Source address uncompression */
668 pr_debug("source address stateless compression\n");
c8a3e7eb
AA		 669 err = uncompress_addr(skb, dev, &hdr.saddr,
670 iphc1 & LOWPAN_IPHC_SAM_MASK, saddr);
8df8c56a
JR		 671 }
672
673 /* Check on error of previous branch */
674 if (err)
56b2c3ee 675 return -EINVAL;
8df8c56a 676
5609c185
AA		 677 switch (iphc1 & (LOWPAN_IPHC_M | LOWPAN_IPHC_DAC)) {
678 case LOWPAN_IPHC_M | LOWPAN_IPHC_DAC:
679 spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
680 ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_DCI(cid));
681 if (!ci) {
682 spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
683 return -EINVAL;
684 }
7fc4cfda 685
5609c185
AA		 686 /* multicast with context */
687 pr_debug("dest: context-based mcast compression\n");
688 err = lowpan_uncompress_multicast_ctx_daddr(skb, ci,
689 &hdr.daddr,
690 iphc1 & LOWPAN_IPHC_DAM_MASK);
691 spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
692 break;
693 case LOWPAN_IPHC_M:
694 /* multicast */
695 err = lowpan_uncompress_multicast_daddr(skb, &hdr.daddr,
696 iphc1 & LOWPAN_IPHC_DAM_MASK);
697 break;
698 case LOWPAN_IPHC_DAC:
699 spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
700 ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_DCI(cid));
701 if (!ci) {
702 spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
703 return -EINVAL;
8df8c56a 704 }
5609c185
AA		 705
706 /* Destination address context based uncompression */
707 pr_debug("DAC bit is set. Handle context based destination address.\n");
708 err = uncompress_ctx_addr(skb, dev, ci, &hdr.daddr,
709 iphc1 & LOWPAN_IPHC_DAM_MASK, daddr);
710 spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
711 break;
712 default:
c8a3e7eb
AA		 713 err = uncompress_addr(skb, dev, &hdr.daddr,
714 iphc1 & LOWPAN_IPHC_DAM_MASK, daddr);
8df8c56a 715 pr_debug("dest: stateless compression mode %d dest %pI6c\n",
c8a3e7eb 716 iphc1 & LOWPAN_IPHC_DAM_MASK, &hdr.daddr);
5609c185 717 break;
8df8c56a
JR		 718 }
719
5609c185
AA		 720 if (err)
721 return -EINVAL;
722
cc6ed268 723 /* Next header data uncompression */
c8a3e7eb 724 if (iphc0 & LOWPAN_IPHC_NH) {
cc6ed268
AA		 725 err = lowpan_nhc_do_uncompression(skb, dev, &hdr);
726 if (err < 0)
11e3ff70 727 return err;
11e3ff70
MT		 728 } else {
729 err = skb_cow(skb, sizeof(hdr));
56b2c3ee 730 if (unlikely(err))
11e3ff70 731 return err;
8df8c56a
JR		 732 }
733
72a5e6bb
AA		 734 switch (lowpan_priv(dev)->lltype) {
735 case LOWPAN_LLTYPE_IEEE802154:
736 if (lowpan_802154_cb(skb)->d_size)
737 hdr.payload_len = htons(lowpan_802154_cb(skb)->d_size -
738 sizeof(struct ipv6hdr));
739 else
740 hdr.payload_len = htons(skb->len);
741 break;
742 default:
743 hdr.payload_len = htons(skb->len);
744 break;
745 }
8df8c56a
JR		 746
747 pr_debug("skb headroom size = %d, data length = %d\n",
748 skb_headroom(skb), skb->len);
749
750 pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n\t"
751 "nexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
752 hdr.version, ntohs(hdr.payload_len), hdr.nexthdr,
753 hdr.hop_limit, &hdr.daddr);
754
f8b36176
MT		 755 skb_push(skb, sizeof(hdr));
756 skb_reset_network_header(skb);
757 skb_copy_to_linear_data(skb, &hdr, sizeof(hdr));
8df8c56a 758
f8b36176 759 raw_dump_table(__func__, "raw header dump", (u8 *)&hdr, sizeof(hdr));
8df8c56a 760
f8b36176 761 return 0;
8df8c56a 762}
01141234 763EXPORT_SYMBOL_GPL(lowpan_header_decompress);
8df8c56a 764
c8a3e7eb
AA		 765static const u8 lowpan_iphc_dam_to_sam_value[] = {
766 [LOWPAN_IPHC_DAM_00] = LOWPAN_IPHC_SAM_00,
767 [LOWPAN_IPHC_DAM_01] = LOWPAN_IPHC_SAM_01,
768 [LOWPAN_IPHC_DAM_10] = LOWPAN_IPHC_SAM_10,
769 [LOWPAN_IPHC_DAM_11] = LOWPAN_IPHC_SAM_11,
770};
771
5609c185
AA		 772static u8 lowpan_compress_ctx_addr(u8 **hc_ptr, const struct in6_addr *ipaddr,
773 const struct lowpan_iphc_ctx *ctx,
774 const unsigned char *lladdr, bool sam)
775{
776 struct in6_addr tmp = {};
777 u8 dam;
778
779 /* check for SAM/DAM = 11 */
780 memcpy(&tmp.s6_addr[8], lladdr, 8);
781 /* second bit-flip (Universe/Local) is done according RFC2464 */
782 tmp.s6_addr[8] ^= 0x02;
783 /* context information are always used */
784 ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen);
785 if (ipv6_addr_equal(&tmp, ipaddr)) {
786 dam = LOWPAN_IPHC_DAM_11;
787 goto out;
788 }
789
790 memset(&tmp, 0, sizeof(tmp));
791 /* check for SAM/DAM = 01 */
792 tmp.s6_addr[11] = 0xFF;
793 tmp.s6_addr[12] = 0xFE;
794 memcpy(&tmp.s6_addr[14], &ipaddr->s6_addr[14], 2);
795 /* context information are always used */
796 ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen);
797 if (ipv6_addr_equal(&tmp, ipaddr)) {
798 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[14], 2);
799 dam = LOWPAN_IPHC_DAM_10;
800 goto out;
801 }
802
803 memset(&tmp, 0, sizeof(tmp));
804 /* check for SAM/DAM = 10, should always match */
805 memcpy(&tmp.s6_addr[8], &ipaddr->s6_addr[8], 8);
806 /* context information are always used */
807 ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen);
808 if (ipv6_addr_equal(&tmp, ipaddr)) {
809 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[8], 8);
810 dam = LOWPAN_IPHC_DAM_01;
811 goto out;
812 }
813
814 WARN_ON_ONCE("context found but no address mode matched\n");
815 return -EINVAL;
816out:
817
818 if (sam)
819 return lowpan_iphc_dam_to_sam_value[dam];
820 else
821 return dam;
822}
823
c8a3e7eb
AA		 824static u8 lowpan_compress_addr_64(u8 **hc_ptr, const struct in6_addr *ipaddr,
825 const unsigned char *lladdr, bool sam)
8df8c56a 826{
c8a3e7eb 827 u8 dam = LOWPAN_IPHC_DAM_00;
8df8c56a
JR		 828
829 if (is_addr_mac_addr_based(ipaddr, lladdr)) {
c8a3e7eb 830 dam = LOWPAN_IPHC_DAM_11; /* 0-bits */
8df8c56a
JR		 831 pr_debug("address compression 0 bits\n");
832 } else if (lowpan_is_iid_16_bit_compressable(ipaddr)) {
833 /* compress IID to 16 bits xxxx::XXXX */
85c71240 834 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[7], 2);
c8a3e7eb 835 dam = LOWPAN_IPHC_DAM_10; /* 16-bits */
8df8c56a 836 raw_dump_inline(NULL, "Compressed ipv6 addr is (16 bits)",
84ca5e03 837 *hc_ptr - 2, 2);
8df8c56a
JR		 838 } else {
839 /* do not compress IID => xxxx::IID */
85c71240 840 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[4], 8);
c8a3e7eb 841 dam = LOWPAN_IPHC_DAM_01; /* 64-bits */
8df8c56a 842 raw_dump_inline(NULL, "Compressed ipv6 addr is (64 bits)",
84ca5e03 843 *hc_ptr - 8, 8);
8df8c56a
JR		 844 }
845
c8a3e7eb
AA		 846 if (sam)
847 return lowpan_iphc_dam_to_sam_value[dam];
848 else
849 return dam;
8df8c56a
JR		 850}
851
b5af9bdb
AA		 852/* lowpan_iphc_get_tc - get the ECN + DCSP fields in hc format */
853static inline u8 lowpan_iphc_get_tc(const struct ipv6hdr *hdr)
854{
855 u8 dscp, ecn;
856
857 /* hdr->priority contains the higher bits of dscp, lower are part of
858 * flow_lbl[0]. Note ECN, DCSP is swapped in ipv6 hdr.
859 */
860 dscp = (hdr->priority << 2) | ((hdr->flow_lbl[0] & 0xc0) >> 6);
861 /* ECN is at the two lower bits from first nibble of flow_lbl[0] */
862 ecn = (hdr->flow_lbl[0] & 0x30);
863 /* for pretty debug output, also shift ecn to get the ecn value */
864 pr_debug("ecn 0x%02x dscp 0x%02x\n", ecn >> 4, dscp);
865 /* ECN is at 0x30 now, shift it to have ECN + DCSP */
866 return (ecn << 2) | dscp;
867}
868
869/* lowpan_iphc_is_flow_lbl_zero - check if flow label is zero */
870static inline bool lowpan_iphc_is_flow_lbl_zero(const struct ipv6hdr *hdr)
871{
872 return ((!(hdr->flow_lbl[0] & 0x0f)) &&
873 !hdr->flow_lbl[1] && !hdr->flow_lbl[2]);
874}
875
876/* lowpan_iphc_tf_compress - compress the traffic class which is set by
877 * ipv6hdr. Return the corresponding format identifier which is used.
878 */
879static u8 lowpan_iphc_tf_compress(u8 **hc_ptr, const struct ipv6hdr *hdr)
880{
881 /* get ecn dscp data in a byteformat as: ECN(hi) + DSCP(lo) */
882 u8 tc = lowpan_iphc_get_tc(hdr), tf[4], val;
883
884 /* printout the traffic class in hc format */
885 pr_debug("tc 0x%02x\n", tc);
886
887 if (lowpan_iphc_is_flow_lbl_zero(hdr)) {
888 if (!tc) {
889 /* 11: Traffic Class and Flow Label are elided. */
890 val = LOWPAN_IPHC_TF_11;
891 } else {
892 /* 10: ECN + DSCP (1 byte), Flow Label is elided.
893 *
894 * 0 1 2 3 4 5 6 7
895 * +-+-+-+-+-+-+-+-+
896 * |ECN| DSCP |
897 * +-+-+-+-+-+-+-+-+
898 */
899 lowpan_push_hc_data(hc_ptr, &tc, sizeof(tc));
900 val = LOWPAN_IPHC_TF_10;
901 }
902 } else {
903 /* check if dscp is zero, it's after the first two bit */
904 if (!(tc & 0x3f)) {
905 /* 01: ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided
906 *
907 * 1 2
908 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
909 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
910 * |ECN|rsv| Flow Label |
911 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
912 */
913 memcpy(&tf[0], &hdr->flow_lbl[0], 3);
914 /* zero the highest 4-bits, contains DCSP + ECN */
915 tf[0] &= ~0xf0;
916 /* set ECN */
917 tf[0] |= (tc & 0xc0);
918
919 lowpan_push_hc_data(hc_ptr, tf, 3);
920 val = LOWPAN_IPHC_TF_01;
921 } else {
922 /* 00: ECN + DSCP + 4-bit Pad + Flow Label (4 bytes)
923 *
924 * 1 2 3
925 * 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
926 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
927 * |ECN| DSCP | rsv | Flow Label |
928 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
929 */
930 memcpy(&tf[0], &tc, sizeof(tc));
931 /* highest nibble of flow_lbl[0] is part of DSCP + ECN
932 * which will be the 4-bit pad and will be filled with
933 * zeros afterwards.
934 */
935 memcpy(&tf[1], &hdr->flow_lbl[0], 3);
936 /* zero the 4-bit pad, which is reserved */
937 tf[1] &= ~0xf0;
938
939 lowpan_push_hc_data(hc_ptr, tf, 4);
940 val = LOWPAN_IPHC_TF_00;
941 }
942 }
943
944 return val;
945}
946
5609c185
AA		 947static u8 lowpan_iphc_mcast_ctx_addr_compress(u8 **hc_ptr,
948 const struct lowpan_iphc_ctx *ctx,
949 const struct in6_addr *ipaddr)
950{
951 u8 data[6];
952
953 /* flags/scope, reserved (RIID) */
954 memcpy(data, &ipaddr->s6_addr[1], 2);
955 /* group ID */
956 memcpy(&data[1], &ipaddr->s6_addr[11], 4);
957 lowpan_push_hc_data(hc_ptr, data, 6);
958
959 return LOWPAN_IPHC_DAM_00;
960}
961
09bf420f
AA		 962static u8 lowpan_iphc_mcast_addr_compress(u8 **hc_ptr,
963 const struct in6_addr *ipaddr)
964{
965 u8 val;
966
967 if (lowpan_is_mcast_addr_compressable8(ipaddr)) {
968 pr_debug("compressed to 1 octet\n");
969 /* use last byte */
970 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[15], 1);
971 val = LOWPAN_IPHC_DAM_11;
972 } else if (lowpan_is_mcast_addr_compressable32(ipaddr)) {
973 pr_debug("compressed to 4 octets\n");
974 /* second byte + the last three */
975 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[1], 1);
976 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[13], 3);
977 val = LOWPAN_IPHC_DAM_10;
978 } else if (lowpan_is_mcast_addr_compressable48(ipaddr)) {
979 pr_debug("compressed to 6 octets\n");
980 /* second byte + the last five */
981 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[1], 1);
982 lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[11], 5);
983 val = LOWPAN_IPHC_DAM_01;
984 } else {
985 pr_debug("using full address\n");
986 lowpan_push_hc_data(hc_ptr, ipaddr->s6_addr, 16);
987 val = LOWPAN_IPHC_DAM_00;
988 }
989
990 return val;
991}
992
a6f77389
AA		 993int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
994 const void *daddr, const void *saddr)
8df8c56a 995{
5609c185 996 u8 iphc0, iphc1, *hc_ptr, cid = 0;
8df8c56a 997 struct ipv6hdr *hdr;
bf513fd6 998 u8 head[LOWPAN_IPHC_MAX_HC_BUF_LEN] = {};
5609c185
AA		 999 struct lowpan_iphc_ctx *dci, *sci, dci_entry, sci_entry;
1000 int ret, ipv6_daddr_type, ipv6_saddr_type;
8df8c56a 1001
a6f77389 1002 if (skb->protocol != htons(ETH_P_IPV6))
8df8c56a
JR		 1003 return -EINVAL;
1004
1005 hdr = ipv6_hdr(skb);
84ca5e03 1006 hc_ptr = head + 2;
8df8c56a
JR		 1007
1008 pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n"
1009 "\tnexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
4710d806
VB		 1010 hdr->version, ntohs(hdr->payload_len), hdr->nexthdr,
1011 hdr->hop_limit, &hdr->daddr);
8df8c56a
JR		 1012
1013 raw_dump_table(__func__, "raw skb network header dump",
4710d806 1014 skb_network_header(skb), sizeof(struct ipv6hdr));
8df8c56a 1015
4710d806 1016 /* As we copy some bit-length fields, in the IPHC encoding bytes,
8df8c56a
JR		 1017 * we sometimes use |=
1018 * If the field is 0, and the current bit value in memory is 1,
1019 * this does not work. We therefore reset the IPHC encoding here
1020 */
1021 iphc0 = LOWPAN_DISPATCH_IPHC;
1022 iphc1 = 0;
1023
a6f77389
AA		 1024 raw_dump_inline(__func__, "saddr", saddr, EUI64_ADDR_LEN);
1025 raw_dump_inline(__func__, "daddr", daddr, EUI64_ADDR_LEN);
8df8c56a 1026
7fc4cfda 1027 raw_dump_table(__func__, "sending raw skb network uncompressed packet",
4710d806 1028 skb->data, skb->len);
8df8c56a 1029
5609c185
AA		 1030 ipv6_daddr_type = ipv6_addr_type(&hdr->daddr);
1031 spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
1032 if (ipv6_daddr_type & IPV6_ADDR_MULTICAST)
1033 dci = lowpan_iphc_ctx_get_by_mcast_addr(dev, &hdr->daddr);
1034 else
1035 dci = lowpan_iphc_ctx_get_by_addr(dev, &hdr->daddr);
1036 if (dci) {
1037 memcpy(&dci_entry, dci, sizeof(*dci));
1038 cid |= dci->id;
1039 }
1040 spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
1041
1042 spin_lock_bh(&lowpan_priv(dev)->ctx.lock);
1043 sci = lowpan_iphc_ctx_get_by_addr(dev, &hdr->saddr);
1044 if (sci) {
1045 memcpy(&sci_entry, sci, sizeof(*sci));
1046 cid |= (sci->id << 4);
1047 }
1048 spin_unlock_bh(&lowpan_priv(dev)->ctx.lock);
1049
1050 /* if cid is zero it will be compressed */
1051 if (cid) {
1052 iphc1 |= LOWPAN_IPHC_CID;
1053 lowpan_push_hc_data(&hc_ptr, &cid, sizeof(cid));
1054 }
1055
b5af9bdb
AA		 1056 /* Traffic Class, Flow Label compression */
1057 iphc0 |= lowpan_iphc_tf_compress(&hc_ptr, hdr);
8df8c56a
JR		 1058
1059 /* NOTE: payload length is always compressed */
1060
cc6ed268
AA		 1061 /* Check if we provide the nhc format for nexthdr and compression
1062 * functionality. If not nexthdr is handled inline and not compressed.
1063 */
607b0bd3
AA		 1064 ret = lowpan_nhc_check_compression(skb, hdr, &hc_ptr);
1065 if (ret == -ENOENT)
1066 lowpan_push_hc_data(&hc_ptr, &hdr->nexthdr,
1067 sizeof(hdr->nexthdr));
1068 else
c8a3e7eb 1069 iphc0 |= LOWPAN_IPHC_NH;
8df8c56a 1070
4710d806 1071 /* Hop limit
8df8c56a
JR		 1072 * if 1: compress, encoding is 01
1073 * if 64: compress, encoding is 10
1074 * if 255: compress, encoding is 11
1075 * else do not compress
1076 */
1077 switch (hdr->hop_limit) {
1078 case 1:
c8a3e7eb 1079 iphc0 |= LOWPAN_IPHC_HLIM_01;
8df8c56a
JR		 1080 break;
1081 case 64:
c8a3e7eb 1082 iphc0 |= LOWPAN_IPHC_HLIM_10;
8df8c56a
JR		 1083 break;
1084 case 255:
c8a3e7eb 1085 iphc0 |= LOWPAN_IPHC_HLIM_11;
8df8c56a
JR		 1086 break;
1087 default:
85c71240
AA		 1088 lowpan_push_hc_data(&hc_ptr, &hdr->hop_limit,
1089 sizeof(hdr->hop_limit));
8df8c56a
JR		 1090 }
1091
5609c185 1092 ipv6_saddr_type = ipv6_addr_type(&hdr->saddr);
8df8c56a 1093 /* source address compression */
5609c185 1094 if (ipv6_saddr_type == IPV6_ADDR_ANY) {
8df8c56a
JR		 1095 pr_debug("source address is unspecified, setting SAC\n");
1096 iphc1 |= LOWPAN_IPHC_SAC;
8df8c56a 1097 } else {
5609c185
AA		 1098 if (sci) {
1099 iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, &hdr->saddr,
1100 &sci_entry, saddr,
1101 true);
1102 iphc1 |= LOWPAN_IPHC_SAC;
556a5bfc 1103 } else {
5609c185
AA		 1104 if (ipv6_saddr_type & IPV6_ADDR_LINKLOCAL) {
1105 iphc1 |= lowpan_compress_addr_64(&hc_ptr,
1106 &hdr->saddr,
1107 saddr, true);
1108 pr_debug("source address unicast link-local %pI6c iphc1 0x%02x\n",
1109 &hdr->saddr, iphc1);
1110 } else {
1111 pr_debug("send the full source address\n");
1112 lowpan_push_hc_data(&hc_ptr,
1113 hdr->saddr.s6_addr, 16);
1114 }
556a5bfc 1115 }
8df8c56a
JR		 1116 }
1117
1118 /* destination address compression */
5609c185 1119 if (ipv6_daddr_type & IPV6_ADDR_MULTICAST) {
8df8c56a 1120 pr_debug("destination address is multicast: ");
8790404d 1121 iphc1 |= LOWPAN_IPHC_M;
5609c185
AA		 1122 if (dci) {
1123 iphc1 |= lowpan_iphc_mcast_ctx_addr_compress(&hc_ptr,
1124 &dci_entry,
1125 &hdr->daddr);
8790404d 1126 iphc1 |= LOWPAN_IPHC_DAC;
5609c185 1127 } else {
5609c185
AA		 1128 iphc1 |= lowpan_iphc_mcast_addr_compress(&hc_ptr,
1129 &hdr->daddr);
1130 }
8df8c56a 1131 } else {
5609c185
AA		 1132 if (dci) {
1133 iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, &hdr->daddr,
1134 &dci_entry, daddr,
1135 false);
1136 iphc1 |= LOWPAN_IPHC_DAC;
8df8c56a 1137 } else {
5609c185
AA		 1138 if (ipv6_daddr_type & IPV6_ADDR_LINKLOCAL) {
1139 iphc1 |= lowpan_compress_addr_64(&hc_ptr,
1140 &hdr->daddr,
1141 daddr, false);
1142 pr_debug("dest address unicast link-local %pI6c iphc1 0x%02x\n",
1143 &hdr->daddr, iphc1);
1144 } else {
1145 pr_debug("dest address unicast %pI6c\n",
1146 &hdr->daddr);
1147 lowpan_push_hc_data(&hc_ptr,
1148 hdr->daddr.s6_addr, 16);
1149 }
8df8c56a
JR		 1150 }
1151 }
1152
cc6ed268 1153 /* next header compression */
c8a3e7eb 1154 if (iphc0 & LOWPAN_IPHC_NH) {
cc6ed268
AA		 1155 ret = lowpan_nhc_do_compression(skb, hdr, &hc_ptr);
1156 if (ret < 0)
1157 return ret;
1158 }
8df8c56a
JR		 1159
1160 head[0] = iphc0;
1161 head[1] = iphc1;
1162
1163 skb_pull(skb, sizeof(struct ipv6hdr));
1164 skb_reset_transport_header(skb);
84ca5e03 1165 memcpy(skb_push(skb, hc_ptr - head), head, hc_ptr - head);
8df8c56a
JR		 1166 skb_reset_network_header(skb);
1167
84ca5e03 1168 pr_debug("header len %d skb %u\n", (int)(hc_ptr - head), skb->len);
8df8c56a
JR		 1169
1170 raw_dump_table(__func__, "raw skb data dump compressed",
4710d806 1171 skb->data, skb->len);
8df8c56a
JR		 1172 return 0;
1173}
1174EXPORT_SYMBOL_GPL(lowpan_header_compress);
Linux 6.x block layer and io_uring tree(s)