Commit | Line | Data |
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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 |
154 | static 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 | ||
170 | static 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 |
202 | static struct lowpan_iphc_ctx * |
203 | lowpan_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 | ||
213 | static struct lowpan_iphc_ctx * | |
214 | lowpan_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 | ||
257 | static struct lowpan_iphc_ctx * | |
258 | lowpan_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 |
299 | static 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 |
358 | static 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 |
421 | static 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 |
474 | static 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 */ |
499 | static 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 */ | |
509 | static 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 */ | |
521 | static 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 | */ | |
540 | static 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 |
601 | static 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 |
607 | int 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 | 763 | EXPORT_SYMBOL_GPL(lowpan_header_decompress); |
8df8c56a | 764 | |
c8a3e7eb AA |
765 | static 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 |
772 | static 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)); | |
24c4a81d | 791 | /* check for SAM/DAM = 10 */ |
5609c185 AA |
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)); | |
24c4a81d | 804 | /* check for SAM/DAM = 01, should always match */ |
5609c185 AA |
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 | ||
2306f656 AA |
814 | WARN_ONCE(1, "context found but no address mode matched\n"); |
815 | return LOWPAN_IPHC_DAM_00; | |
5609c185 AA |
816 | out: |
817 | ||
818 | if (sam) | |
819 | return lowpan_iphc_dam_to_sam_value[dam]; | |
820 | else | |
821 | return dam; | |
822 | } | |
823 | ||
c8a3e7eb AA |
824 | static 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 */ |
853 | static 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 */ | |
870 | static 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 | */ | |
879 | static 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 |
947 | static 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 |
962 | static 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 |
993 | int 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 | } | |
1174 | EXPORT_SYMBOL_GPL(lowpan_header_compress); |