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 | ||
feb2add3 AA |
151 | #define lowpan_is_linklocal_zero_padded(a) \ |
152 | (!(hdr->saddr.s6_addr[1] & 0x3f) && \ | |
153 | !hdr->saddr.s6_addr16[1] && \ | |
154 | !hdr->saddr.s6_addr32[1]) | |
155 | ||
5609c185 AA |
156 | #define LOWPAN_IPHC_CID_DCI(cid) (cid & 0x0f) |
157 | #define LOWPAN_IPHC_CID_SCI(cid) ((cid & 0xf0) >> 4) | |
158 | ||
8911d774 AA |
159 | static inline void iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr, |
160 | const void *lladdr) | |
161 | { | |
162 | /* fe:80::XXXX:XXXX:XXXX:XXXX | |
163 | * \_________________/ | |
164 | * hwaddr | |
165 | */ | |
166 | ipaddr->s6_addr[0] = 0xFE; | |
167 | ipaddr->s6_addr[1] = 0x80; | |
168 | memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN); | |
169 | /* second bit-flip (Universe/Local) | |
170 | * is done according RFC2464 | |
171 | */ | |
172 | ipaddr->s6_addr[8] ^= 0x02; | |
173 | } | |
174 | ||
175 | static inline void iphc_uncompress_802154_lladdr(struct in6_addr *ipaddr, | |
176 | const void *lladdr) | |
177 | { | |
178 | const struct ieee802154_addr *addr = lladdr; | |
179 | u8 eui64[EUI64_ADDR_LEN] = { }; | |
180 | ||
181 | switch (addr->mode) { | |
182 | case IEEE802154_ADDR_LONG: | |
183 | ieee802154_le64_to_be64(eui64, &addr->extended_addr); | |
184 | iphc_uncompress_eui64_lladdr(ipaddr, eui64); | |
185 | break; | |
186 | case IEEE802154_ADDR_SHORT: | |
187 | /* fe:80::ff:fe00:XXXX | |
188 | * \__/ | |
189 | * short_addr | |
190 | * | |
191 | * Universe/Local bit is zero. | |
192 | */ | |
193 | ipaddr->s6_addr[0] = 0xFE; | |
194 | ipaddr->s6_addr[1] = 0x80; | |
195 | ipaddr->s6_addr[11] = 0xFF; | |
196 | ipaddr->s6_addr[12] = 0xFE; | |
197 | ieee802154_le16_to_be16(&ipaddr->s6_addr16[7], | |
198 | &addr->short_addr); | |
199 | break; | |
200 | default: | |
201 | /* should never handled and filtered by 802154 6lowpan */ | |
202 | WARN_ON_ONCE(1); | |
203 | break; | |
204 | } | |
205 | } | |
206 | ||
5609c185 AA |
207 | static struct lowpan_iphc_ctx * |
208 | lowpan_iphc_ctx_get_by_id(const struct net_device *dev, u8 id) | |
209 | { | |
2e4d60cb | 210 | struct lowpan_iphc_ctx *ret = &lowpan_dev(dev)->ctx.table[id]; |
5609c185 AA |
211 | |
212 | if (!lowpan_iphc_ctx_is_active(ret)) | |
213 | return NULL; | |
214 | ||
215 | return ret; | |
216 | } | |
217 | ||
218 | static struct lowpan_iphc_ctx * | |
219 | lowpan_iphc_ctx_get_by_addr(const struct net_device *dev, | |
220 | const struct in6_addr *addr) | |
221 | { | |
2e4d60cb | 222 | struct lowpan_iphc_ctx *table = lowpan_dev(dev)->ctx.table; |
5609c185 AA |
223 | struct lowpan_iphc_ctx *ret = NULL; |
224 | struct in6_addr addr_pfx; | |
225 | u8 addr_plen; | |
226 | int i; | |
227 | ||
228 | for (i = 0; i < LOWPAN_IPHC_CTX_TABLE_SIZE; i++) { | |
229 | /* Check if context is valid. A context that is not valid | |
230 | * MUST NOT be used for compression. | |
231 | */ | |
232 | if (!lowpan_iphc_ctx_is_active(&table[i]) || | |
233 | !lowpan_iphc_ctx_is_compression(&table[i])) | |
234 | continue; | |
235 | ||
236 | ipv6_addr_prefix(&addr_pfx, addr, table[i].plen); | |
237 | ||
238 | /* if prefix len < 64, the remaining bits until 64th bit is | |
239 | * zero. Otherwise we use table[i]->plen. | |
240 | */ | |
241 | if (table[i].plen < 64) | |
242 | addr_plen = 64; | |
243 | else | |
244 | addr_plen = table[i].plen; | |
245 | ||
246 | if (ipv6_prefix_equal(&addr_pfx, &table[i].pfx, addr_plen)) { | |
247 | /* remember first match */ | |
248 | if (!ret) { | |
249 | ret = &table[i]; | |
250 | continue; | |
251 | } | |
252 | ||
253 | /* get the context with longest prefix len */ | |
254 | if (table[i].plen > ret->plen) | |
255 | ret = &table[i]; | |
256 | } | |
257 | } | |
258 | ||
259 | return ret; | |
260 | } | |
261 | ||
262 | static struct lowpan_iphc_ctx * | |
263 | lowpan_iphc_ctx_get_by_mcast_addr(const struct net_device *dev, | |
264 | const struct in6_addr *addr) | |
265 | { | |
2e4d60cb | 266 | struct lowpan_iphc_ctx *table = lowpan_dev(dev)->ctx.table; |
5609c185 AA |
267 | struct lowpan_iphc_ctx *ret = NULL; |
268 | struct in6_addr addr_mcast, network_pfx = {}; | |
269 | int i; | |
270 | ||
271 | /* init mcast address with */ | |
272 | memcpy(&addr_mcast, addr, sizeof(*addr)); | |
273 | ||
274 | for (i = 0; i < LOWPAN_IPHC_CTX_TABLE_SIZE; i++) { | |
275 | /* Check if context is valid. A context that is not valid | |
276 | * MUST NOT be used for compression. | |
277 | */ | |
278 | if (!lowpan_iphc_ctx_is_active(&table[i]) || | |
279 | !lowpan_iphc_ctx_is_compression(&table[i])) | |
280 | continue; | |
281 | ||
282 | /* setting plen */ | |
283 | addr_mcast.s6_addr[3] = table[i].plen; | |
284 | /* get network prefix to copy into multicast address */ | |
285 | ipv6_addr_prefix(&network_pfx, &table[i].pfx, | |
286 | table[i].plen); | |
287 | /* setting network prefix */ | |
288 | memcpy(&addr_mcast.s6_addr[4], &network_pfx, 8); | |
289 | ||
290 | if (ipv6_addr_equal(addr, &addr_mcast)) { | |
291 | ret = &table[i]; | |
292 | break; | |
293 | } | |
294 | } | |
295 | ||
296 | return ret; | |
297 | } | |
298 | ||
4710d806 | 299 | /* Uncompress address function for source and |
8df8c56a JR |
300 | * destination address(non-multicast). |
301 | * | |
c8a3e7eb | 302 | * address_mode is the masked value for sam or dam value |
8df8c56a | 303 | */ |
8911d774 AA |
304 | static int uncompress_addr(struct sk_buff *skb, const struct net_device *dev, |
305 | struct in6_addr *ipaddr, u8 address_mode, | |
306 | const void *lladdr) | |
8df8c56a JR |
307 | { |
308 | bool fail; | |
309 | ||
310 | switch (address_mode) { | |
c8a3e7eb AA |
311 | /* SAM and DAM are the same here */ |
312 | case LOWPAN_IPHC_DAM_00: | |
8df8c56a JR |
313 | /* for global link addresses */ |
314 | fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16); | |
315 | break; | |
c8a3e7eb AA |
316 | case LOWPAN_IPHC_SAM_01: |
317 | case LOWPAN_IPHC_DAM_01: | |
8df8c56a JR |
318 | /* fe:80::XXXX:XXXX:XXXX:XXXX */ |
319 | ipaddr->s6_addr[0] = 0xFE; | |
320 | ipaddr->s6_addr[1] = 0x80; | |
321 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8); | |
322 | break; | |
c8a3e7eb AA |
323 | case LOWPAN_IPHC_SAM_10: |
324 | case LOWPAN_IPHC_DAM_10: | |
8df8c56a JR |
325 | /* fe:80::ff:fe00:XXXX */ |
326 | ipaddr->s6_addr[0] = 0xFE; | |
327 | ipaddr->s6_addr[1] = 0x80; | |
328 | ipaddr->s6_addr[11] = 0xFF; | |
329 | ipaddr->s6_addr[12] = 0xFE; | |
330 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2); | |
331 | break; | |
c8a3e7eb AA |
332 | case LOWPAN_IPHC_SAM_11: |
333 | case LOWPAN_IPHC_DAM_11: | |
8df8c56a | 334 | fail = false; |
2e4d60cb | 335 | switch (lowpan_dev(dev)->lltype) { |
8911d774 AA |
336 | case LOWPAN_LLTYPE_IEEE802154: |
337 | iphc_uncompress_802154_lladdr(ipaddr, lladdr); | |
8df8c56a JR |
338 | break; |
339 | default: | |
8911d774 AA |
340 | iphc_uncompress_eui64_lladdr(ipaddr, lladdr); |
341 | break; | |
8df8c56a JR |
342 | } |
343 | break; | |
344 | default: | |
345 | pr_debug("Invalid address mode value: 0x%x\n", address_mode); | |
346 | return -EINVAL; | |
347 | } | |
348 | ||
349 | if (fail) { | |
350 | pr_debug("Failed to fetch skb data\n"); | |
351 | return -EIO; | |
352 | } | |
353 | ||
354 | raw_dump_inline(NULL, "Reconstructed ipv6 addr is", | |
355 | ipaddr->s6_addr, 16); | |
356 | ||
357 | return 0; | |
358 | } | |
359 | ||
4710d806 | 360 | /* Uncompress address function for source context |
8df8c56a JR |
361 | * based address(non-multicast). |
362 | */ | |
5609c185 AA |
363 | static int uncompress_ctx_addr(struct sk_buff *skb, |
364 | const struct net_device *dev, | |
365 | const struct lowpan_iphc_ctx *ctx, | |
366 | struct in6_addr *ipaddr, u8 address_mode, | |
367 | const void *lladdr) | |
8df8c56a | 368 | { |
5609c185 AA |
369 | bool fail; |
370 | ||
c8a3e7eb | 371 | switch (address_mode) { |
5609c185 AA |
372 | /* SAM and DAM are the same here */ |
373 | case LOWPAN_IPHC_DAM_00: | |
374 | fail = false; | |
375 | /* SAM_00 -> unspec address :: | |
8df8c56a | 376 | * Do nothing, address is already :: |
5609c185 AA |
377 | * |
378 | * DAM 00 -> reserved should never occur. | |
8df8c56a JR |
379 | */ |
380 | break; | |
c8a3e7eb | 381 | case LOWPAN_IPHC_SAM_01: |
5609c185 AA |
382 | case LOWPAN_IPHC_DAM_01: |
383 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8); | |
384 | ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen); | |
385 | break; | |
c8a3e7eb | 386 | case LOWPAN_IPHC_SAM_10: |
5609c185 AA |
387 | case LOWPAN_IPHC_DAM_10: |
388 | ipaddr->s6_addr[11] = 0xFF; | |
389 | ipaddr->s6_addr[12] = 0xFE; | |
390 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2); | |
391 | ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen); | |
392 | break; | |
c8a3e7eb | 393 | case LOWPAN_IPHC_SAM_11: |
5609c185 AA |
394 | case LOWPAN_IPHC_DAM_11: |
395 | fail = false; | |
2e4d60cb | 396 | switch (lowpan_dev(dev)->lltype) { |
5609c185 AA |
397 | case LOWPAN_LLTYPE_IEEE802154: |
398 | iphc_uncompress_802154_lladdr(ipaddr, lladdr); | |
399 | break; | |
400 | default: | |
401 | iphc_uncompress_eui64_lladdr(ipaddr, lladdr); | |
402 | break; | |
403 | } | |
404 | ipv6_addr_prefix_copy(ipaddr, &ctx->pfx, ctx->plen); | |
405 | break; | |
8df8c56a | 406 | default: |
c8a3e7eb | 407 | pr_debug("Invalid sam value: 0x%x\n", address_mode); |
8df8c56a JR |
408 | return -EINVAL; |
409 | } | |
410 | ||
5609c185 AA |
411 | if (fail) { |
412 | pr_debug("Failed to fetch skb data\n"); | |
413 | return -EIO; | |
414 | } | |
415 | ||
8df8c56a JR |
416 | raw_dump_inline(NULL, |
417 | "Reconstructed context based ipv6 src addr is", | |
418 | ipaddr->s6_addr, 16); | |
419 | ||
420 | return 0; | |
421 | } | |
422 | ||
8df8c56a JR |
423 | /* Uncompress function for multicast destination address, |
424 | * when M bit is set. | |
425 | */ | |
7fc4cfda MH |
426 | static int lowpan_uncompress_multicast_daddr(struct sk_buff *skb, |
427 | struct in6_addr *ipaddr, | |
c8a3e7eb | 428 | u8 address_mode) |
8df8c56a JR |
429 | { |
430 | bool fail; | |
431 | ||
c8a3e7eb | 432 | switch (address_mode) { |
8df8c56a JR |
433 | case LOWPAN_IPHC_DAM_00: |
434 | /* 00: 128 bits. The full address | |
435 | * is carried in-line. | |
436 | */ | |
437 | fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16); | |
438 | break; | |
439 | case LOWPAN_IPHC_DAM_01: | |
440 | /* 01: 48 bits. The address takes | |
441 | * the form ffXX::00XX:XXXX:XXXX. | |
442 | */ | |
443 | ipaddr->s6_addr[0] = 0xFF; | |
444 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1); | |
445 | fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[11], 5); | |
446 | break; | |
447 | case LOWPAN_IPHC_DAM_10: | |
448 | /* 10: 32 bits. The address takes | |
449 | * the form ffXX::00XX:XXXX. | |
450 | */ | |
451 | ipaddr->s6_addr[0] = 0xFF; | |
452 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1); | |
453 | fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[13], 3); | |
454 | break; | |
455 | case LOWPAN_IPHC_DAM_11: | |
456 | /* 11: 8 bits. The address takes | |
457 | * the form ff02::00XX. | |
458 | */ | |
459 | ipaddr->s6_addr[0] = 0xFF; | |
460 | ipaddr->s6_addr[1] = 0x02; | |
461 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[15], 1); | |
462 | break; | |
463 | default: | |
c8a3e7eb | 464 | pr_debug("DAM value has a wrong value: 0x%x\n", address_mode); |
8df8c56a JR |
465 | return -EINVAL; |
466 | } | |
467 | ||
468 | if (fail) { | |
469 | pr_debug("Failed to fetch skb data\n"); | |
470 | return -EIO; | |
471 | } | |
472 | ||
473 | raw_dump_inline(NULL, "Reconstructed ipv6 multicast addr is", | |
7fc4cfda | 474 | ipaddr->s6_addr, 16); |
8df8c56a JR |
475 | |
476 | return 0; | |
477 | } | |
478 | ||
5609c185 AA |
479 | static int lowpan_uncompress_multicast_ctx_daddr(struct sk_buff *skb, |
480 | struct lowpan_iphc_ctx *ctx, | |
481 | struct in6_addr *ipaddr, | |
482 | u8 address_mode) | |
483 | { | |
484 | struct in6_addr network_pfx = {}; | |
485 | bool fail; | |
486 | ||
487 | ipaddr->s6_addr[0] = 0xFF; | |
488 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 2); | |
489 | fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[12], 4); | |
4c23d874 | 490 | if (fail) |
5609c185 AA |
491 | return -EIO; |
492 | ||
493 | /* take prefix_len and network prefix from the context */ | |
494 | ipaddr->s6_addr[3] = ctx->plen; | |
495 | /* get network prefix to copy into multicast address */ | |
496 | ipv6_addr_prefix(&network_pfx, &ctx->pfx, ctx->plen); | |
497 | /* setting network prefix */ | |
498 | memcpy(&ipaddr->s6_addr[4], &network_pfx, 8); | |
499 | ||
500 | return 0; | |
501 | } | |
502 | ||
b5af9bdb AA |
503 | /* get the ecn values from iphc tf format and set it to ipv6hdr */ |
504 | static inline void lowpan_iphc_tf_set_ecn(struct ipv6hdr *hdr, const u8 *tf) | |
505 | { | |
506 | /* get the two higher bits which is ecn */ | |
507 | u8 ecn = tf[0] & 0xc0; | |
508 | ||
509 | /* ECN takes 0x30 in hdr->flow_lbl[0] */ | |
510 | hdr->flow_lbl[0] |= (ecn >> 2); | |
511 | } | |
512 | ||
513 | /* get the dscp values from iphc tf format and set it to ipv6hdr */ | |
514 | static inline void lowpan_iphc_tf_set_dscp(struct ipv6hdr *hdr, const u8 *tf) | |
515 | { | |
516 | /* DSCP is at place after ECN */ | |
517 | u8 dscp = tf[0] & 0x3f; | |
518 | ||
519 | /* The four highest bits need to be set at hdr->priority */ | |
520 | hdr->priority |= ((dscp & 0x3c) >> 2); | |
521 | /* The two lower bits is part of hdr->flow_lbl[0] */ | |
522 | hdr->flow_lbl[0] |= ((dscp & 0x03) << 6); | |
523 | } | |
524 | ||
525 | /* get the flow label values from iphc tf format and set it to ipv6hdr */ | |
526 | static inline void lowpan_iphc_tf_set_lbl(struct ipv6hdr *hdr, const u8 *lbl) | |
527 | { | |
528 | /* flow label is always some array started with lower nibble of | |
529 | * flow_lbl[0] and followed with two bytes afterwards. Inside inline | |
530 | * data the flow_lbl position can be different, which will be handled | |
531 | * by lbl pointer. E.g. case "01" vs "00" the traffic class is 8 bit | |
532 | * shifted, the different lbl pointer will handle that. | |
533 | * | |
534 | * The flow label will started at lower nibble of flow_lbl[0], the | |
535 | * higher nibbles are part of DSCP + ECN. | |
536 | */ | |
537 | hdr->flow_lbl[0] |= lbl[0] & 0x0f; | |
538 | memcpy(&hdr->flow_lbl[1], &lbl[1], 2); | |
539 | } | |
540 | ||
541 | /* lowpan_iphc_tf_decompress - decompress the traffic class. | |
542 | * This function will return zero on success, a value lower than zero if | |
543 | * failed. | |
544 | */ | |
545 | static int lowpan_iphc_tf_decompress(struct sk_buff *skb, struct ipv6hdr *hdr, | |
546 | u8 val) | |
547 | { | |
548 | u8 tf[4]; | |
549 | ||
550 | /* Traffic Class and Flow Label */ | |
551 | switch (val) { | |
552 | case LOWPAN_IPHC_TF_00: | |
553 | /* ECN + DSCP + 4-bit Pad + Flow Label (4 bytes) */ | |
554 | if (lowpan_fetch_skb(skb, tf, 4)) | |
555 | return -EINVAL; | |
556 | ||
557 | /* 1 2 3 | |
558 | * 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 | |
559 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
560 | * |ECN| DSCP | rsv | Flow Label | | |
561 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
562 | */ | |
563 | lowpan_iphc_tf_set_ecn(hdr, tf); | |
564 | lowpan_iphc_tf_set_dscp(hdr, tf); | |
565 | lowpan_iphc_tf_set_lbl(hdr, &tf[1]); | |
566 | break; | |
567 | case LOWPAN_IPHC_TF_01: | |
568 | /* ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided. */ | |
569 | if (lowpan_fetch_skb(skb, tf, 3)) | |
570 | return -EINVAL; | |
571 | ||
572 | /* 1 2 | |
573 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 | |
574 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
575 | * |ECN|rsv| Flow Label | | |
576 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
577 | */ | |
578 | lowpan_iphc_tf_set_ecn(hdr, tf); | |
579 | lowpan_iphc_tf_set_lbl(hdr, &tf[0]); | |
580 | break; | |
581 | case LOWPAN_IPHC_TF_10: | |
582 | /* ECN + DSCP (1 byte), Flow Label is elided. */ | |
583 | if (lowpan_fetch_skb(skb, tf, 1)) | |
584 | return -EINVAL; | |
585 | ||
586 | /* 0 1 2 3 4 5 6 7 | |
587 | * +-+-+-+-+-+-+-+-+ | |
588 | * |ECN| DSCP | | |
589 | * +-+-+-+-+-+-+-+-+ | |
590 | */ | |
591 | lowpan_iphc_tf_set_ecn(hdr, tf); | |
592 | lowpan_iphc_tf_set_dscp(hdr, tf); | |
593 | break; | |
594 | case LOWPAN_IPHC_TF_11: | |
595 | /* Traffic Class and Flow Label are elided */ | |
596 | break; | |
597 | default: | |
598 | WARN_ON_ONCE(1); | |
599 | return -EINVAL; | |
600 | } | |
601 | ||
602 | return 0; | |
603 | } | |
604 | ||
8df8c56a | 605 | /* TTL uncompression values */ |
c8a3e7eb AA |
606 | static const u8 lowpan_ttl_values[] = { |
607 | [LOWPAN_IPHC_HLIM_01] = 1, | |
608 | [LOWPAN_IPHC_HLIM_10] = 64, | |
609 | [LOWPAN_IPHC_HLIM_11] = 255, | |
610 | }; | |
8df8c56a | 611 | |
8911d774 AA |
612 | int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev, |
613 | const void *daddr, const void *saddr) | |
8df8c56a JR |
614 | { |
615 | struct ipv6hdr hdr = {}; | |
5609c185 AA |
616 | struct lowpan_iphc_ctx *ci; |
617 | u8 iphc0, iphc1, cid = 0; | |
8df8c56a JR |
618 | int err; |
619 | ||
620 | raw_dump_table(__func__, "raw skb data dump uncompressed", | |
4710d806 | 621 | skb->data, skb->len); |
8df8c56a | 622 | |
478208e3 AA |
623 | if (lowpan_fetch_skb(skb, &iphc0, sizeof(iphc0)) || |
624 | lowpan_fetch_skb(skb, &iphc1, sizeof(iphc1))) | |
8911d774 AA |
625 | return -EINVAL; |
626 | ||
8df8c56a JR |
627 | hdr.version = 6; |
628 | ||
5609c185 AA |
629 | /* default CID = 0, another if the CID flag is set */ |
630 | if (iphc1 & LOWPAN_IPHC_CID) { | |
631 | if (lowpan_fetch_skb(skb, &cid, sizeof(cid))) | |
632 | return -EINVAL; | |
633 | } | |
634 | ||
b5af9bdb AA |
635 | err = lowpan_iphc_tf_decompress(skb, &hdr, |
636 | iphc0 & LOWPAN_IPHC_TF_MASK); | |
637 | if (err < 0) | |
638 | return err; | |
8df8c56a JR |
639 | |
640 | /* Next Header */ | |
c8a3e7eb | 641 | if (!(iphc0 & LOWPAN_IPHC_NH)) { |
8df8c56a | 642 | /* Next header is carried inline */ |
4ebc960f | 643 | if (lowpan_fetch_skb(skb, &hdr.nexthdr, sizeof(hdr.nexthdr))) |
56b2c3ee | 644 | return -EINVAL; |
8df8c56a JR |
645 | |
646 | pr_debug("NH flag is set, next header carried inline: %02x\n", | |
647 | hdr.nexthdr); | |
648 | } | |
649 | ||
650 | /* Hop Limit */ | |
c8a3e7eb AA |
651 | if ((iphc0 & LOWPAN_IPHC_HLIM_MASK) != LOWPAN_IPHC_HLIM_00) { |
652 | hdr.hop_limit = lowpan_ttl_values[iphc0 & LOWPAN_IPHC_HLIM_MASK]; | |
4710d806 | 653 | } else { |
4ebc960f AA |
654 | if (lowpan_fetch_skb(skb, &hdr.hop_limit, |
655 | sizeof(hdr.hop_limit))) | |
56b2c3ee | 656 | return -EINVAL; |
8df8c56a JR |
657 | } |
658 | ||
8df8c56a | 659 | if (iphc1 & LOWPAN_IPHC_SAC) { |
2e4d60cb | 660 | spin_lock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
661 | ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_SCI(cid)); |
662 | if (!ci) { | |
2e4d60cb | 663 | spin_unlock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
664 | return -EINVAL; |
665 | } | |
666 | ||
8df8c56a | 667 | pr_debug("SAC bit is set. Handle context based source address.\n"); |
5609c185 AA |
668 | err = uncompress_ctx_addr(skb, dev, ci, &hdr.saddr, |
669 | iphc1 & LOWPAN_IPHC_SAM_MASK, saddr); | |
2e4d60cb | 670 | spin_unlock_bh(&lowpan_dev(dev)->ctx.lock); |
8df8c56a JR |
671 | } else { |
672 | /* Source address uncompression */ | |
673 | pr_debug("source address stateless compression\n"); | |
c8a3e7eb AA |
674 | err = uncompress_addr(skb, dev, &hdr.saddr, |
675 | iphc1 & LOWPAN_IPHC_SAM_MASK, saddr); | |
8df8c56a JR |
676 | } |
677 | ||
678 | /* Check on error of previous branch */ | |
679 | if (err) | |
56b2c3ee | 680 | return -EINVAL; |
8df8c56a | 681 | |
5609c185 AA |
682 | switch (iphc1 & (LOWPAN_IPHC_M | LOWPAN_IPHC_DAC)) { |
683 | case LOWPAN_IPHC_M | LOWPAN_IPHC_DAC: | |
2e4d60cb | 684 | spin_lock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
685 | ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_DCI(cid)); |
686 | if (!ci) { | |
2e4d60cb | 687 | spin_unlock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
688 | return -EINVAL; |
689 | } | |
7fc4cfda | 690 | |
5609c185 AA |
691 | /* multicast with context */ |
692 | pr_debug("dest: context-based mcast compression\n"); | |
693 | err = lowpan_uncompress_multicast_ctx_daddr(skb, ci, | |
694 | &hdr.daddr, | |
695 | iphc1 & LOWPAN_IPHC_DAM_MASK); | |
2e4d60cb | 696 | spin_unlock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
697 | break; |
698 | case LOWPAN_IPHC_M: | |
699 | /* multicast */ | |
700 | err = lowpan_uncompress_multicast_daddr(skb, &hdr.daddr, | |
701 | iphc1 & LOWPAN_IPHC_DAM_MASK); | |
702 | break; | |
703 | case LOWPAN_IPHC_DAC: | |
2e4d60cb | 704 | spin_lock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
705 | ci = lowpan_iphc_ctx_get_by_id(dev, LOWPAN_IPHC_CID_DCI(cid)); |
706 | if (!ci) { | |
2e4d60cb | 707 | spin_unlock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 | 708 | return -EINVAL; |
8df8c56a | 709 | } |
5609c185 AA |
710 | |
711 | /* Destination address context based uncompression */ | |
712 | pr_debug("DAC bit is set. Handle context based destination address.\n"); | |
713 | err = uncompress_ctx_addr(skb, dev, ci, &hdr.daddr, | |
714 | iphc1 & LOWPAN_IPHC_DAM_MASK, daddr); | |
2e4d60cb | 715 | spin_unlock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
716 | break; |
717 | default: | |
c8a3e7eb AA |
718 | err = uncompress_addr(skb, dev, &hdr.daddr, |
719 | iphc1 & LOWPAN_IPHC_DAM_MASK, daddr); | |
8df8c56a | 720 | pr_debug("dest: stateless compression mode %d dest %pI6c\n", |
c8a3e7eb | 721 | iphc1 & LOWPAN_IPHC_DAM_MASK, &hdr.daddr); |
5609c185 | 722 | break; |
8df8c56a JR |
723 | } |
724 | ||
5609c185 AA |
725 | if (err) |
726 | return -EINVAL; | |
727 | ||
cc6ed268 | 728 | /* Next header data uncompression */ |
c8a3e7eb | 729 | if (iphc0 & LOWPAN_IPHC_NH) { |
cc6ed268 AA |
730 | err = lowpan_nhc_do_uncompression(skb, dev, &hdr); |
731 | if (err < 0) | |
11e3ff70 | 732 | return err; |
11e3ff70 MT |
733 | } else { |
734 | err = skb_cow(skb, sizeof(hdr)); | |
56b2c3ee | 735 | if (unlikely(err)) |
11e3ff70 | 736 | return err; |
8df8c56a JR |
737 | } |
738 | ||
2e4d60cb | 739 | switch (lowpan_dev(dev)->lltype) { |
72a5e6bb AA |
740 | case LOWPAN_LLTYPE_IEEE802154: |
741 | if (lowpan_802154_cb(skb)->d_size) | |
742 | hdr.payload_len = htons(lowpan_802154_cb(skb)->d_size - | |
743 | sizeof(struct ipv6hdr)); | |
744 | else | |
745 | hdr.payload_len = htons(skb->len); | |
746 | break; | |
747 | default: | |
748 | hdr.payload_len = htons(skb->len); | |
749 | break; | |
750 | } | |
8df8c56a JR |
751 | |
752 | pr_debug("skb headroom size = %d, data length = %d\n", | |
753 | skb_headroom(skb), skb->len); | |
754 | ||
755 | pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n\t" | |
756 | "nexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n", | |
757 | hdr.version, ntohs(hdr.payload_len), hdr.nexthdr, | |
758 | hdr.hop_limit, &hdr.daddr); | |
759 | ||
f8b36176 MT |
760 | skb_push(skb, sizeof(hdr)); |
761 | skb_reset_network_header(skb); | |
762 | skb_copy_to_linear_data(skb, &hdr, sizeof(hdr)); | |
8df8c56a | 763 | |
f8b36176 | 764 | raw_dump_table(__func__, "raw header dump", (u8 *)&hdr, sizeof(hdr)); |
8df8c56a | 765 | |
f8b36176 | 766 | return 0; |
8df8c56a | 767 | } |
01141234 | 768 | EXPORT_SYMBOL_GPL(lowpan_header_decompress); |
8df8c56a | 769 | |
c8a3e7eb AA |
770 | static const u8 lowpan_iphc_dam_to_sam_value[] = { |
771 | [LOWPAN_IPHC_DAM_00] = LOWPAN_IPHC_SAM_00, | |
772 | [LOWPAN_IPHC_DAM_01] = LOWPAN_IPHC_SAM_01, | |
773 | [LOWPAN_IPHC_DAM_10] = LOWPAN_IPHC_SAM_10, | |
774 | [LOWPAN_IPHC_DAM_11] = LOWPAN_IPHC_SAM_11, | |
775 | }; | |
776 | ||
5609c185 AA |
777 | static u8 lowpan_compress_ctx_addr(u8 **hc_ptr, const struct in6_addr *ipaddr, |
778 | const struct lowpan_iphc_ctx *ctx, | |
779 | const unsigned char *lladdr, bool sam) | |
780 | { | |
781 | struct in6_addr tmp = {}; | |
782 | u8 dam; | |
783 | ||
784 | /* check for SAM/DAM = 11 */ | |
785 | memcpy(&tmp.s6_addr[8], lladdr, 8); | |
786 | /* second bit-flip (Universe/Local) is done according RFC2464 */ | |
787 | tmp.s6_addr[8] ^= 0x02; | |
788 | /* context information are always used */ | |
789 | ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen); | |
790 | if (ipv6_addr_equal(&tmp, ipaddr)) { | |
791 | dam = LOWPAN_IPHC_DAM_11; | |
792 | goto out; | |
793 | } | |
794 | ||
795 | memset(&tmp, 0, sizeof(tmp)); | |
24c4a81d | 796 | /* check for SAM/DAM = 10 */ |
5609c185 AA |
797 | tmp.s6_addr[11] = 0xFF; |
798 | tmp.s6_addr[12] = 0xFE; | |
799 | memcpy(&tmp.s6_addr[14], &ipaddr->s6_addr[14], 2); | |
800 | /* context information are always used */ | |
801 | ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen); | |
802 | if (ipv6_addr_equal(&tmp, ipaddr)) { | |
803 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[14], 2); | |
804 | dam = LOWPAN_IPHC_DAM_10; | |
805 | goto out; | |
806 | } | |
807 | ||
808 | memset(&tmp, 0, sizeof(tmp)); | |
24c4a81d | 809 | /* check for SAM/DAM = 01, should always match */ |
5609c185 AA |
810 | memcpy(&tmp.s6_addr[8], &ipaddr->s6_addr[8], 8); |
811 | /* context information are always used */ | |
812 | ipv6_addr_prefix_copy(&tmp, &ctx->pfx, ctx->plen); | |
813 | if (ipv6_addr_equal(&tmp, ipaddr)) { | |
814 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[8], 8); | |
815 | dam = LOWPAN_IPHC_DAM_01; | |
816 | goto out; | |
817 | } | |
818 | ||
2306f656 AA |
819 | WARN_ONCE(1, "context found but no address mode matched\n"); |
820 | return LOWPAN_IPHC_DAM_00; | |
5609c185 AA |
821 | out: |
822 | ||
823 | if (sam) | |
824 | return lowpan_iphc_dam_to_sam_value[dam]; | |
825 | else | |
826 | return dam; | |
827 | } | |
828 | ||
c8a3e7eb AA |
829 | static u8 lowpan_compress_addr_64(u8 **hc_ptr, const struct in6_addr *ipaddr, |
830 | const unsigned char *lladdr, bool sam) | |
8df8c56a | 831 | { |
c8a3e7eb | 832 | u8 dam = LOWPAN_IPHC_DAM_00; |
8df8c56a JR |
833 | |
834 | if (is_addr_mac_addr_based(ipaddr, lladdr)) { | |
c8a3e7eb | 835 | dam = LOWPAN_IPHC_DAM_11; /* 0-bits */ |
8df8c56a JR |
836 | pr_debug("address compression 0 bits\n"); |
837 | } else if (lowpan_is_iid_16_bit_compressable(ipaddr)) { | |
838 | /* compress IID to 16 bits xxxx::XXXX */ | |
85c71240 | 839 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[7], 2); |
c8a3e7eb | 840 | dam = LOWPAN_IPHC_DAM_10; /* 16-bits */ |
8df8c56a | 841 | raw_dump_inline(NULL, "Compressed ipv6 addr is (16 bits)", |
84ca5e03 | 842 | *hc_ptr - 2, 2); |
8df8c56a JR |
843 | } else { |
844 | /* do not compress IID => xxxx::IID */ | |
85c71240 | 845 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[4], 8); |
c8a3e7eb | 846 | dam = LOWPAN_IPHC_DAM_01; /* 64-bits */ |
8df8c56a | 847 | raw_dump_inline(NULL, "Compressed ipv6 addr is (64 bits)", |
84ca5e03 | 848 | *hc_ptr - 8, 8); |
8df8c56a JR |
849 | } |
850 | ||
c8a3e7eb AA |
851 | if (sam) |
852 | return lowpan_iphc_dam_to_sam_value[dam]; | |
853 | else | |
854 | return dam; | |
8df8c56a JR |
855 | } |
856 | ||
b5af9bdb AA |
857 | /* lowpan_iphc_get_tc - get the ECN + DCSP fields in hc format */ |
858 | static inline u8 lowpan_iphc_get_tc(const struct ipv6hdr *hdr) | |
859 | { | |
860 | u8 dscp, ecn; | |
861 | ||
862 | /* hdr->priority contains the higher bits of dscp, lower are part of | |
863 | * flow_lbl[0]. Note ECN, DCSP is swapped in ipv6 hdr. | |
864 | */ | |
865 | dscp = (hdr->priority << 2) | ((hdr->flow_lbl[0] & 0xc0) >> 6); | |
866 | /* ECN is at the two lower bits from first nibble of flow_lbl[0] */ | |
867 | ecn = (hdr->flow_lbl[0] & 0x30); | |
868 | /* for pretty debug output, also shift ecn to get the ecn value */ | |
869 | pr_debug("ecn 0x%02x dscp 0x%02x\n", ecn >> 4, dscp); | |
870 | /* ECN is at 0x30 now, shift it to have ECN + DCSP */ | |
871 | return (ecn << 2) | dscp; | |
872 | } | |
873 | ||
874 | /* lowpan_iphc_is_flow_lbl_zero - check if flow label is zero */ | |
875 | static inline bool lowpan_iphc_is_flow_lbl_zero(const struct ipv6hdr *hdr) | |
876 | { | |
877 | return ((!(hdr->flow_lbl[0] & 0x0f)) && | |
878 | !hdr->flow_lbl[1] && !hdr->flow_lbl[2]); | |
879 | } | |
880 | ||
881 | /* lowpan_iphc_tf_compress - compress the traffic class which is set by | |
882 | * ipv6hdr. Return the corresponding format identifier which is used. | |
883 | */ | |
884 | static u8 lowpan_iphc_tf_compress(u8 **hc_ptr, const struct ipv6hdr *hdr) | |
885 | { | |
886 | /* get ecn dscp data in a byteformat as: ECN(hi) + DSCP(lo) */ | |
887 | u8 tc = lowpan_iphc_get_tc(hdr), tf[4], val; | |
888 | ||
889 | /* printout the traffic class in hc format */ | |
890 | pr_debug("tc 0x%02x\n", tc); | |
891 | ||
892 | if (lowpan_iphc_is_flow_lbl_zero(hdr)) { | |
893 | if (!tc) { | |
894 | /* 11: Traffic Class and Flow Label are elided. */ | |
895 | val = LOWPAN_IPHC_TF_11; | |
896 | } else { | |
897 | /* 10: ECN + DSCP (1 byte), Flow Label is elided. | |
898 | * | |
899 | * 0 1 2 3 4 5 6 7 | |
900 | * +-+-+-+-+-+-+-+-+ | |
901 | * |ECN| DSCP | | |
902 | * +-+-+-+-+-+-+-+-+ | |
903 | */ | |
904 | lowpan_push_hc_data(hc_ptr, &tc, sizeof(tc)); | |
905 | val = LOWPAN_IPHC_TF_10; | |
906 | } | |
907 | } else { | |
908 | /* check if dscp is zero, it's after the first two bit */ | |
909 | if (!(tc & 0x3f)) { | |
910 | /* 01: ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided | |
911 | * | |
912 | * 1 2 | |
913 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 | |
914 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
915 | * |ECN|rsv| Flow Label | | |
916 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
917 | */ | |
918 | memcpy(&tf[0], &hdr->flow_lbl[0], 3); | |
919 | /* zero the highest 4-bits, contains DCSP + ECN */ | |
920 | tf[0] &= ~0xf0; | |
921 | /* set ECN */ | |
922 | tf[0] |= (tc & 0xc0); | |
923 | ||
924 | lowpan_push_hc_data(hc_ptr, tf, 3); | |
925 | val = LOWPAN_IPHC_TF_01; | |
926 | } else { | |
927 | /* 00: ECN + DSCP + 4-bit Pad + Flow Label (4 bytes) | |
928 | * | |
929 | * 1 2 3 | |
930 | * 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 | |
931 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
932 | * |ECN| DSCP | rsv | Flow Label | | |
933 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
934 | */ | |
935 | memcpy(&tf[0], &tc, sizeof(tc)); | |
936 | /* highest nibble of flow_lbl[0] is part of DSCP + ECN | |
937 | * which will be the 4-bit pad and will be filled with | |
938 | * zeros afterwards. | |
939 | */ | |
940 | memcpy(&tf[1], &hdr->flow_lbl[0], 3); | |
941 | /* zero the 4-bit pad, which is reserved */ | |
942 | tf[1] &= ~0xf0; | |
943 | ||
944 | lowpan_push_hc_data(hc_ptr, tf, 4); | |
945 | val = LOWPAN_IPHC_TF_00; | |
946 | } | |
947 | } | |
948 | ||
949 | return val; | |
950 | } | |
951 | ||
5609c185 AA |
952 | static u8 lowpan_iphc_mcast_ctx_addr_compress(u8 **hc_ptr, |
953 | const struct lowpan_iphc_ctx *ctx, | |
954 | const struct in6_addr *ipaddr) | |
955 | { | |
956 | u8 data[6]; | |
957 | ||
958 | /* flags/scope, reserved (RIID) */ | |
959 | memcpy(data, &ipaddr->s6_addr[1], 2); | |
960 | /* group ID */ | |
961 | memcpy(&data[1], &ipaddr->s6_addr[11], 4); | |
962 | lowpan_push_hc_data(hc_ptr, data, 6); | |
963 | ||
964 | return LOWPAN_IPHC_DAM_00; | |
965 | } | |
966 | ||
09bf420f AA |
967 | static u8 lowpan_iphc_mcast_addr_compress(u8 **hc_ptr, |
968 | const struct in6_addr *ipaddr) | |
969 | { | |
970 | u8 val; | |
971 | ||
972 | if (lowpan_is_mcast_addr_compressable8(ipaddr)) { | |
973 | pr_debug("compressed to 1 octet\n"); | |
974 | /* use last byte */ | |
975 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[15], 1); | |
976 | val = LOWPAN_IPHC_DAM_11; | |
977 | } else if (lowpan_is_mcast_addr_compressable32(ipaddr)) { | |
978 | pr_debug("compressed to 4 octets\n"); | |
979 | /* second byte + the last three */ | |
980 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[1], 1); | |
981 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[13], 3); | |
982 | val = LOWPAN_IPHC_DAM_10; | |
983 | } else if (lowpan_is_mcast_addr_compressable48(ipaddr)) { | |
984 | pr_debug("compressed to 6 octets\n"); | |
985 | /* second byte + the last five */ | |
986 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[1], 1); | |
987 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr[11], 5); | |
988 | val = LOWPAN_IPHC_DAM_01; | |
989 | } else { | |
990 | pr_debug("using full address\n"); | |
991 | lowpan_push_hc_data(hc_ptr, ipaddr->s6_addr, 16); | |
992 | val = LOWPAN_IPHC_DAM_00; | |
993 | } | |
994 | ||
995 | return val; | |
996 | } | |
997 | ||
a6f77389 AA |
998 | int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev, |
999 | const void *daddr, const void *saddr) | |
8df8c56a | 1000 | { |
5609c185 | 1001 | u8 iphc0, iphc1, *hc_ptr, cid = 0; |
8df8c56a | 1002 | struct ipv6hdr *hdr; |
bf513fd6 | 1003 | u8 head[LOWPAN_IPHC_MAX_HC_BUF_LEN] = {}; |
5609c185 AA |
1004 | struct lowpan_iphc_ctx *dci, *sci, dci_entry, sci_entry; |
1005 | int ret, ipv6_daddr_type, ipv6_saddr_type; | |
8df8c56a | 1006 | |
a6f77389 | 1007 | if (skb->protocol != htons(ETH_P_IPV6)) |
8df8c56a JR |
1008 | return -EINVAL; |
1009 | ||
1010 | hdr = ipv6_hdr(skb); | |
84ca5e03 | 1011 | hc_ptr = head + 2; |
8df8c56a JR |
1012 | |
1013 | pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n" | |
1014 | "\tnexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n", | |
4710d806 VB |
1015 | hdr->version, ntohs(hdr->payload_len), hdr->nexthdr, |
1016 | hdr->hop_limit, &hdr->daddr); | |
8df8c56a JR |
1017 | |
1018 | raw_dump_table(__func__, "raw skb network header dump", | |
4710d806 | 1019 | skb_network_header(skb), sizeof(struct ipv6hdr)); |
8df8c56a | 1020 | |
4710d806 | 1021 | /* As we copy some bit-length fields, in the IPHC encoding bytes, |
8df8c56a JR |
1022 | * we sometimes use |= |
1023 | * If the field is 0, and the current bit value in memory is 1, | |
1024 | * this does not work. We therefore reset the IPHC encoding here | |
1025 | */ | |
1026 | iphc0 = LOWPAN_DISPATCH_IPHC; | |
1027 | iphc1 = 0; | |
1028 | ||
a6f77389 AA |
1029 | raw_dump_inline(__func__, "saddr", saddr, EUI64_ADDR_LEN); |
1030 | raw_dump_inline(__func__, "daddr", daddr, EUI64_ADDR_LEN); | |
8df8c56a | 1031 | |
7fc4cfda | 1032 | raw_dump_table(__func__, "sending raw skb network uncompressed packet", |
4710d806 | 1033 | skb->data, skb->len); |
8df8c56a | 1034 | |
5609c185 | 1035 | ipv6_daddr_type = ipv6_addr_type(&hdr->daddr); |
2e4d60cb | 1036 | spin_lock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
1037 | if (ipv6_daddr_type & IPV6_ADDR_MULTICAST) |
1038 | dci = lowpan_iphc_ctx_get_by_mcast_addr(dev, &hdr->daddr); | |
1039 | else | |
1040 | dci = lowpan_iphc_ctx_get_by_addr(dev, &hdr->daddr); | |
1041 | if (dci) { | |
1042 | memcpy(&dci_entry, dci, sizeof(*dci)); | |
1043 | cid |= dci->id; | |
1044 | } | |
2e4d60cb | 1045 | spin_unlock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 | 1046 | |
2e4d60cb | 1047 | spin_lock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
1048 | sci = lowpan_iphc_ctx_get_by_addr(dev, &hdr->saddr); |
1049 | if (sci) { | |
1050 | memcpy(&sci_entry, sci, sizeof(*sci)); | |
1051 | cid |= (sci->id << 4); | |
1052 | } | |
2e4d60cb | 1053 | spin_unlock_bh(&lowpan_dev(dev)->ctx.lock); |
5609c185 AA |
1054 | |
1055 | /* if cid is zero it will be compressed */ | |
1056 | if (cid) { | |
1057 | iphc1 |= LOWPAN_IPHC_CID; | |
1058 | lowpan_push_hc_data(&hc_ptr, &cid, sizeof(cid)); | |
1059 | } | |
1060 | ||
b5af9bdb AA |
1061 | /* Traffic Class, Flow Label compression */ |
1062 | iphc0 |= lowpan_iphc_tf_compress(&hc_ptr, hdr); | |
8df8c56a JR |
1063 | |
1064 | /* NOTE: payload length is always compressed */ | |
1065 | ||
cc6ed268 AA |
1066 | /* Check if we provide the nhc format for nexthdr and compression |
1067 | * functionality. If not nexthdr is handled inline and not compressed. | |
1068 | */ | |
607b0bd3 AA |
1069 | ret = lowpan_nhc_check_compression(skb, hdr, &hc_ptr); |
1070 | if (ret == -ENOENT) | |
1071 | lowpan_push_hc_data(&hc_ptr, &hdr->nexthdr, | |
1072 | sizeof(hdr->nexthdr)); | |
1073 | else | |
c8a3e7eb | 1074 | iphc0 |= LOWPAN_IPHC_NH; |
8df8c56a | 1075 | |
4710d806 | 1076 | /* Hop limit |
8df8c56a JR |
1077 | * if 1: compress, encoding is 01 |
1078 | * if 64: compress, encoding is 10 | |
1079 | * if 255: compress, encoding is 11 | |
1080 | * else do not compress | |
1081 | */ | |
1082 | switch (hdr->hop_limit) { | |
1083 | case 1: | |
c8a3e7eb | 1084 | iphc0 |= LOWPAN_IPHC_HLIM_01; |
8df8c56a JR |
1085 | break; |
1086 | case 64: | |
c8a3e7eb | 1087 | iphc0 |= LOWPAN_IPHC_HLIM_10; |
8df8c56a JR |
1088 | break; |
1089 | case 255: | |
c8a3e7eb | 1090 | iphc0 |= LOWPAN_IPHC_HLIM_11; |
8df8c56a JR |
1091 | break; |
1092 | default: | |
85c71240 AA |
1093 | lowpan_push_hc_data(&hc_ptr, &hdr->hop_limit, |
1094 | sizeof(hdr->hop_limit)); | |
8df8c56a JR |
1095 | } |
1096 | ||
5609c185 | 1097 | ipv6_saddr_type = ipv6_addr_type(&hdr->saddr); |
8df8c56a | 1098 | /* source address compression */ |
5609c185 | 1099 | if (ipv6_saddr_type == IPV6_ADDR_ANY) { |
8df8c56a JR |
1100 | pr_debug("source address is unspecified, setting SAC\n"); |
1101 | iphc1 |= LOWPAN_IPHC_SAC; | |
8df8c56a | 1102 | } else { |
5609c185 AA |
1103 | if (sci) { |
1104 | iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, &hdr->saddr, | |
1105 | &sci_entry, saddr, | |
1106 | true); | |
1107 | iphc1 |= LOWPAN_IPHC_SAC; | |
556a5bfc | 1108 | } else { |
feb2add3 AA |
1109 | if (ipv6_saddr_type & IPV6_ADDR_LINKLOCAL && |
1110 | lowpan_is_linklocal_zero_padded(hdr->saddr)) { | |
5609c185 AA |
1111 | iphc1 |= lowpan_compress_addr_64(&hc_ptr, |
1112 | &hdr->saddr, | |
1113 | saddr, true); | |
1114 | pr_debug("source address unicast link-local %pI6c iphc1 0x%02x\n", | |
1115 | &hdr->saddr, iphc1); | |
1116 | } else { | |
1117 | pr_debug("send the full source address\n"); | |
1118 | lowpan_push_hc_data(&hc_ptr, | |
1119 | hdr->saddr.s6_addr, 16); | |
1120 | } | |
556a5bfc | 1121 | } |
8df8c56a JR |
1122 | } |
1123 | ||
1124 | /* destination address compression */ | |
5609c185 | 1125 | if (ipv6_daddr_type & IPV6_ADDR_MULTICAST) { |
8df8c56a | 1126 | pr_debug("destination address is multicast: "); |
8790404d | 1127 | iphc1 |= LOWPAN_IPHC_M; |
5609c185 AA |
1128 | if (dci) { |
1129 | iphc1 |= lowpan_iphc_mcast_ctx_addr_compress(&hc_ptr, | |
1130 | &dci_entry, | |
1131 | &hdr->daddr); | |
8790404d | 1132 | iphc1 |= LOWPAN_IPHC_DAC; |
5609c185 | 1133 | } else { |
5609c185 AA |
1134 | iphc1 |= lowpan_iphc_mcast_addr_compress(&hc_ptr, |
1135 | &hdr->daddr); | |
1136 | } | |
8df8c56a | 1137 | } else { |
5609c185 AA |
1138 | if (dci) { |
1139 | iphc1 |= lowpan_compress_ctx_addr(&hc_ptr, &hdr->daddr, | |
1140 | &dci_entry, daddr, | |
1141 | false); | |
1142 | iphc1 |= LOWPAN_IPHC_DAC; | |
8df8c56a | 1143 | } else { |
feb2add3 AA |
1144 | if (ipv6_daddr_type & IPV6_ADDR_LINKLOCAL && |
1145 | lowpan_is_linklocal_zero_padded(hdr->daddr)) { | |
5609c185 AA |
1146 | iphc1 |= lowpan_compress_addr_64(&hc_ptr, |
1147 | &hdr->daddr, | |
1148 | daddr, false); | |
1149 | pr_debug("dest address unicast link-local %pI6c iphc1 0x%02x\n", | |
1150 | &hdr->daddr, iphc1); | |
1151 | } else { | |
1152 | pr_debug("dest address unicast %pI6c\n", | |
1153 | &hdr->daddr); | |
1154 | lowpan_push_hc_data(&hc_ptr, | |
1155 | hdr->daddr.s6_addr, 16); | |
1156 | } | |
8df8c56a JR |
1157 | } |
1158 | } | |
1159 | ||
cc6ed268 | 1160 | /* next header compression */ |
c8a3e7eb | 1161 | if (iphc0 & LOWPAN_IPHC_NH) { |
cc6ed268 AA |
1162 | ret = lowpan_nhc_do_compression(skb, hdr, &hc_ptr); |
1163 | if (ret < 0) | |
1164 | return ret; | |
1165 | } | |
8df8c56a JR |
1166 | |
1167 | head[0] = iphc0; | |
1168 | head[1] = iphc1; | |
1169 | ||
1170 | skb_pull(skb, sizeof(struct ipv6hdr)); | |
1171 | skb_reset_transport_header(skb); | |
84ca5e03 | 1172 | memcpy(skb_push(skb, hc_ptr - head), head, hc_ptr - head); |
8df8c56a JR |
1173 | skb_reset_network_header(skb); |
1174 | ||
84ca5e03 | 1175 | pr_debug("header len %d skb %u\n", (int)(hc_ptr - head), skb->len); |
8df8c56a JR |
1176 | |
1177 | raw_dump_table(__func__, "raw skb data dump compressed", | |
4710d806 | 1178 | skb->data, skb->len); |
8df8c56a JR |
1179 | return 0; |
1180 | } | |
1181 | EXPORT_SYMBOL_GPL(lowpan_header_compress); |