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 | |
cc6ed268 AA |
59 | #include "nhc.h" |
60 | ||
6350047e AA |
61 | /* Values of fields within the IPHC encoding first byte |
62 | * (C stands for compressed and I for inline) | |
63 | */ | |
64 | #define LOWPAN_IPHC_TF 0x18 | |
65 | ||
66 | #define LOWPAN_IPHC_FL_C 0x10 | |
67 | #define LOWPAN_IPHC_TC_C 0x08 | |
68 | #define LOWPAN_IPHC_NH_C 0x04 | |
69 | #define LOWPAN_IPHC_TTL_1 0x01 | |
70 | #define LOWPAN_IPHC_TTL_64 0x02 | |
71 | #define LOWPAN_IPHC_TTL_255 0x03 | |
72 | #define LOWPAN_IPHC_TTL_I 0x00 | |
73 | ||
74 | /* Values of fields within the IPHC encoding second byte */ | |
75 | #define LOWPAN_IPHC_CID 0x80 | |
76 | ||
77 | #define LOWPAN_IPHC_ADDR_00 0x00 | |
78 | #define LOWPAN_IPHC_ADDR_01 0x01 | |
79 | #define LOWPAN_IPHC_ADDR_02 0x02 | |
80 | #define LOWPAN_IPHC_ADDR_03 0x03 | |
81 | ||
82 | #define LOWPAN_IPHC_SAC 0x40 | |
83 | #define LOWPAN_IPHC_SAM 0x30 | |
84 | ||
85 | #define LOWPAN_IPHC_SAM_BIT 4 | |
86 | ||
87 | #define LOWPAN_IPHC_M 0x08 | |
88 | #define LOWPAN_IPHC_DAC 0x04 | |
89 | #define LOWPAN_IPHC_DAM_00 0x00 | |
90 | #define LOWPAN_IPHC_DAM_01 0x01 | |
91 | #define LOWPAN_IPHC_DAM_10 0x02 | |
92 | #define LOWPAN_IPHC_DAM_11 0x03 | |
93 | ||
94 | #define LOWPAN_IPHC_DAM_BIT 0 | |
95 | ||
96 | /* ipv6 address based on mac | |
97 | * second bit-flip (Universe/Local) is done according RFC2464 | |
98 | */ | |
99 | #define is_addr_mac_addr_based(a, m) \ | |
100 | ((((a)->s6_addr[8]) == (((m)[0]) ^ 0x02)) && \ | |
101 | (((a)->s6_addr[9]) == (m)[1]) && \ | |
102 | (((a)->s6_addr[10]) == (m)[2]) && \ | |
103 | (((a)->s6_addr[11]) == (m)[3]) && \ | |
104 | (((a)->s6_addr[12]) == (m)[4]) && \ | |
105 | (((a)->s6_addr[13]) == (m)[5]) && \ | |
106 | (((a)->s6_addr[14]) == (m)[6]) && \ | |
107 | (((a)->s6_addr[15]) == (m)[7])) | |
108 | ||
109 | /* check whether we can compress the IID to 16 bits, | |
110 | * it's possible for unicast addresses with first 49 bits are zero only. | |
111 | */ | |
112 | #define lowpan_is_iid_16_bit_compressable(a) \ | |
113 | ((((a)->s6_addr16[4]) == 0) && \ | |
114 | (((a)->s6_addr[10]) == 0) && \ | |
115 | (((a)->s6_addr[11]) == 0xff) && \ | |
116 | (((a)->s6_addr[12]) == 0xfe) && \ | |
117 | (((a)->s6_addr[13]) == 0)) | |
118 | ||
119 | /* check whether the 112-bit gid of the multicast address is mappable to: */ | |
120 | ||
121 | /* 48 bits, FFXX::00XX:XXXX:XXXX */ | |
122 | #define lowpan_is_mcast_addr_compressable48(a) \ | |
123 | ((((a)->s6_addr16[1]) == 0) && \ | |
124 | (((a)->s6_addr16[2]) == 0) && \ | |
125 | (((a)->s6_addr16[3]) == 0) && \ | |
126 | (((a)->s6_addr16[4]) == 0) && \ | |
127 | (((a)->s6_addr[10]) == 0)) | |
128 | ||
129 | /* 32 bits, FFXX::00XX:XXXX */ | |
130 | #define lowpan_is_mcast_addr_compressable32(a) \ | |
131 | ((((a)->s6_addr16[1]) == 0) && \ | |
132 | (((a)->s6_addr16[2]) == 0) && \ | |
133 | (((a)->s6_addr16[3]) == 0) && \ | |
134 | (((a)->s6_addr16[4]) == 0) && \ | |
135 | (((a)->s6_addr16[5]) == 0) && \ | |
136 | (((a)->s6_addr[12]) == 0)) | |
137 | ||
138 | /* 8 bits, FF02::00XX */ | |
139 | #define lowpan_is_mcast_addr_compressable8(a) \ | |
140 | ((((a)->s6_addr[1]) == 2) && \ | |
141 | (((a)->s6_addr16[1]) == 0) && \ | |
142 | (((a)->s6_addr16[2]) == 0) && \ | |
143 | (((a)->s6_addr16[3]) == 0) && \ | |
144 | (((a)->s6_addr16[4]) == 0) && \ | |
145 | (((a)->s6_addr16[5]) == 0) && \ | |
146 | (((a)->s6_addr16[6]) == 0) && \ | |
147 | (((a)->s6_addr[14]) == 0)) | |
148 | ||
8911d774 AA |
149 | static inline void iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr, |
150 | const void *lladdr) | |
151 | { | |
152 | /* fe:80::XXXX:XXXX:XXXX:XXXX | |
153 | * \_________________/ | |
154 | * hwaddr | |
155 | */ | |
156 | ipaddr->s6_addr[0] = 0xFE; | |
157 | ipaddr->s6_addr[1] = 0x80; | |
158 | memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN); | |
159 | /* second bit-flip (Universe/Local) | |
160 | * is done according RFC2464 | |
161 | */ | |
162 | ipaddr->s6_addr[8] ^= 0x02; | |
163 | } | |
164 | ||
165 | static inline void iphc_uncompress_802154_lladdr(struct in6_addr *ipaddr, | |
166 | const void *lladdr) | |
167 | { | |
168 | const struct ieee802154_addr *addr = lladdr; | |
169 | u8 eui64[EUI64_ADDR_LEN] = { }; | |
170 | ||
171 | switch (addr->mode) { | |
172 | case IEEE802154_ADDR_LONG: | |
173 | ieee802154_le64_to_be64(eui64, &addr->extended_addr); | |
174 | iphc_uncompress_eui64_lladdr(ipaddr, eui64); | |
175 | break; | |
176 | case IEEE802154_ADDR_SHORT: | |
177 | /* fe:80::ff:fe00:XXXX | |
178 | * \__/ | |
179 | * short_addr | |
180 | * | |
181 | * Universe/Local bit is zero. | |
182 | */ | |
183 | ipaddr->s6_addr[0] = 0xFE; | |
184 | ipaddr->s6_addr[1] = 0x80; | |
185 | ipaddr->s6_addr[11] = 0xFF; | |
186 | ipaddr->s6_addr[12] = 0xFE; | |
187 | ieee802154_le16_to_be16(&ipaddr->s6_addr16[7], | |
188 | &addr->short_addr); | |
189 | break; | |
190 | default: | |
191 | /* should never handled and filtered by 802154 6lowpan */ | |
192 | WARN_ON_ONCE(1); | |
193 | break; | |
194 | } | |
195 | } | |
196 | ||
4710d806 | 197 | /* Uncompress address function for source and |
8df8c56a JR |
198 | * destination address(non-multicast). |
199 | * | |
200 | * address_mode is sam value or dam value. | |
201 | */ | |
8911d774 AA |
202 | static int uncompress_addr(struct sk_buff *skb, const struct net_device *dev, |
203 | struct in6_addr *ipaddr, u8 address_mode, | |
204 | const void *lladdr) | |
8df8c56a JR |
205 | { |
206 | bool fail; | |
207 | ||
208 | switch (address_mode) { | |
209 | case LOWPAN_IPHC_ADDR_00: | |
210 | /* for global link addresses */ | |
211 | fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16); | |
212 | break; | |
213 | case LOWPAN_IPHC_ADDR_01: | |
214 | /* fe:80::XXXX:XXXX:XXXX:XXXX */ | |
215 | ipaddr->s6_addr[0] = 0xFE; | |
216 | ipaddr->s6_addr[1] = 0x80; | |
217 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[8], 8); | |
218 | break; | |
219 | case LOWPAN_IPHC_ADDR_02: | |
220 | /* fe:80::ff:fe00:XXXX */ | |
221 | ipaddr->s6_addr[0] = 0xFE; | |
222 | ipaddr->s6_addr[1] = 0x80; | |
223 | ipaddr->s6_addr[11] = 0xFF; | |
224 | ipaddr->s6_addr[12] = 0xFE; | |
225 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[14], 2); | |
226 | break; | |
227 | case LOWPAN_IPHC_ADDR_03: | |
228 | fail = false; | |
8911d774 AA |
229 | switch (lowpan_priv(dev)->lltype) { |
230 | case LOWPAN_LLTYPE_IEEE802154: | |
231 | iphc_uncompress_802154_lladdr(ipaddr, lladdr); | |
8df8c56a JR |
232 | break; |
233 | default: | |
8911d774 AA |
234 | iphc_uncompress_eui64_lladdr(ipaddr, lladdr); |
235 | break; | |
8df8c56a JR |
236 | } |
237 | break; | |
238 | default: | |
239 | pr_debug("Invalid address mode value: 0x%x\n", address_mode); | |
240 | return -EINVAL; | |
241 | } | |
242 | ||
243 | if (fail) { | |
244 | pr_debug("Failed to fetch skb data\n"); | |
245 | return -EIO; | |
246 | } | |
247 | ||
248 | raw_dump_inline(NULL, "Reconstructed ipv6 addr is", | |
249 | ipaddr->s6_addr, 16); | |
250 | ||
251 | return 0; | |
252 | } | |
253 | ||
4710d806 | 254 | /* Uncompress address function for source context |
8df8c56a JR |
255 | * based address(non-multicast). |
256 | */ | |
257 | static int uncompress_context_based_src_addr(struct sk_buff *skb, | |
4710d806 VB |
258 | struct in6_addr *ipaddr, |
259 | const u8 sam) | |
8df8c56a JR |
260 | { |
261 | switch (sam) { | |
262 | case LOWPAN_IPHC_ADDR_00: | |
263 | /* unspec address :: | |
264 | * Do nothing, address is already :: | |
265 | */ | |
266 | break; | |
267 | case LOWPAN_IPHC_ADDR_01: | |
268 | /* TODO */ | |
269 | case LOWPAN_IPHC_ADDR_02: | |
270 | /* TODO */ | |
271 | case LOWPAN_IPHC_ADDR_03: | |
272 | /* TODO */ | |
273 | netdev_warn(skb->dev, "SAM value 0x%x not supported\n", sam); | |
274 | return -EINVAL; | |
275 | default: | |
276 | pr_debug("Invalid sam value: 0x%x\n", sam); | |
277 | return -EINVAL; | |
278 | } | |
279 | ||
280 | raw_dump_inline(NULL, | |
281 | "Reconstructed context based ipv6 src addr is", | |
282 | ipaddr->s6_addr, 16); | |
283 | ||
284 | return 0; | |
285 | } | |
286 | ||
8df8c56a JR |
287 | /* Uncompress function for multicast destination address, |
288 | * when M bit is set. | |
289 | */ | |
7fc4cfda MH |
290 | static int lowpan_uncompress_multicast_daddr(struct sk_buff *skb, |
291 | struct in6_addr *ipaddr, | |
292 | const u8 dam) | |
8df8c56a JR |
293 | { |
294 | bool fail; | |
295 | ||
296 | switch (dam) { | |
297 | case LOWPAN_IPHC_DAM_00: | |
298 | /* 00: 128 bits. The full address | |
299 | * is carried in-line. | |
300 | */ | |
301 | fail = lowpan_fetch_skb(skb, ipaddr->s6_addr, 16); | |
302 | break; | |
303 | case LOWPAN_IPHC_DAM_01: | |
304 | /* 01: 48 bits. The address takes | |
305 | * the form ffXX::00XX:XXXX:XXXX. | |
306 | */ | |
307 | ipaddr->s6_addr[0] = 0xFF; | |
308 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1); | |
309 | fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[11], 5); | |
310 | break; | |
311 | case LOWPAN_IPHC_DAM_10: | |
312 | /* 10: 32 bits. The address takes | |
313 | * the form ffXX::00XX:XXXX. | |
314 | */ | |
315 | ipaddr->s6_addr[0] = 0xFF; | |
316 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[1], 1); | |
317 | fail |= lowpan_fetch_skb(skb, &ipaddr->s6_addr[13], 3); | |
318 | break; | |
319 | case LOWPAN_IPHC_DAM_11: | |
320 | /* 11: 8 bits. The address takes | |
321 | * the form ff02::00XX. | |
322 | */ | |
323 | ipaddr->s6_addr[0] = 0xFF; | |
324 | ipaddr->s6_addr[1] = 0x02; | |
325 | fail = lowpan_fetch_skb(skb, &ipaddr->s6_addr[15], 1); | |
326 | break; | |
327 | default: | |
328 | pr_debug("DAM value has a wrong value: 0x%x\n", dam); | |
329 | return -EINVAL; | |
330 | } | |
331 | ||
332 | if (fail) { | |
333 | pr_debug("Failed to fetch skb data\n"); | |
334 | return -EIO; | |
335 | } | |
336 | ||
337 | raw_dump_inline(NULL, "Reconstructed ipv6 multicast addr is", | |
7fc4cfda | 338 | ipaddr->s6_addr, 16); |
8df8c56a JR |
339 | |
340 | return 0; | |
341 | } | |
342 | ||
8df8c56a JR |
343 | /* TTL uncompression values */ |
344 | static const u8 lowpan_ttl_values[] = { 0, 1, 64, 255 }; | |
345 | ||
8911d774 AA |
346 | int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev, |
347 | const void *daddr, const void *saddr) | |
8df8c56a JR |
348 | { |
349 | struct ipv6hdr hdr = {}; | |
8911d774 | 350 | u8 iphc0, iphc1, tmp, num_context = 0; |
8df8c56a JR |
351 | int err; |
352 | ||
353 | raw_dump_table(__func__, "raw skb data dump uncompressed", | |
4710d806 | 354 | skb->data, skb->len); |
8df8c56a | 355 | |
478208e3 AA |
356 | if (lowpan_fetch_skb(skb, &iphc0, sizeof(iphc0)) || |
357 | lowpan_fetch_skb(skb, &iphc1, sizeof(iphc1))) | |
8911d774 AA |
358 | return -EINVAL; |
359 | ||
8df8c56a JR |
360 | /* another if the CID flag is set */ |
361 | if (iphc1 & LOWPAN_IPHC_CID) { | |
362 | pr_debug("CID flag is set, increase header with one\n"); | |
4ebc960f | 363 | if (lowpan_fetch_skb(skb, &num_context, sizeof(num_context))) |
56b2c3ee | 364 | return -EINVAL; |
8df8c56a JR |
365 | } |
366 | ||
367 | hdr.version = 6; | |
368 | ||
369 | /* Traffic Class and Flow Label */ | |
370 | switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) { | |
4710d806 | 371 | /* Traffic Class and FLow Label carried in-line |
8df8c56a JR |
372 | * ECN + DSCP + 4-bit Pad + Flow Label (4 bytes) |
373 | */ | |
374 | case 0: /* 00b */ | |
4ebc960f | 375 | if (lowpan_fetch_skb(skb, &tmp, sizeof(tmp))) |
56b2c3ee | 376 | return -EINVAL; |
8df8c56a JR |
377 | |
378 | memcpy(&hdr.flow_lbl, &skb->data[0], 3); | |
379 | skb_pull(skb, 3); | |
380 | hdr.priority = ((tmp >> 2) & 0x0f); | |
381 | hdr.flow_lbl[0] = ((tmp >> 2) & 0x30) | (tmp << 6) | | |
382 | (hdr.flow_lbl[0] & 0x0f); | |
383 | break; | |
4710d806 | 384 | /* Traffic class carried in-line |
8df8c56a JR |
385 | * ECN + DSCP (1 byte), Flow Label is elided |
386 | */ | |
387 | case 2: /* 10b */ | |
4ebc960f | 388 | if (lowpan_fetch_skb(skb, &tmp, sizeof(tmp))) |
56b2c3ee | 389 | return -EINVAL; |
8df8c56a JR |
390 | |
391 | hdr.priority = ((tmp >> 2) & 0x0f); | |
392 | hdr.flow_lbl[0] = ((tmp << 6) & 0xC0) | ((tmp >> 2) & 0x30); | |
393 | break; | |
4710d806 | 394 | /* Flow Label carried in-line |
8df8c56a JR |
395 | * ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided |
396 | */ | |
397 | case 1: /* 01b */ | |
4ebc960f | 398 | if (lowpan_fetch_skb(skb, &tmp, sizeof(tmp))) |
56b2c3ee | 399 | return -EINVAL; |
8df8c56a | 400 | |
77e867b5 | 401 | hdr.flow_lbl[0] = (tmp & 0x0F) | ((tmp >> 2) & 0x30); |
8df8c56a JR |
402 | memcpy(&hdr.flow_lbl[1], &skb->data[0], 2); |
403 | skb_pull(skb, 2); | |
404 | break; | |
405 | /* Traffic Class and Flow Label are elided */ | |
406 | case 3: /* 11b */ | |
407 | break; | |
408 | default: | |
409 | break; | |
410 | } | |
411 | ||
412 | /* Next Header */ | |
413 | if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) { | |
414 | /* Next header is carried inline */ | |
4ebc960f | 415 | if (lowpan_fetch_skb(skb, &hdr.nexthdr, sizeof(hdr.nexthdr))) |
56b2c3ee | 416 | return -EINVAL; |
8df8c56a JR |
417 | |
418 | pr_debug("NH flag is set, next header carried inline: %02x\n", | |
419 | hdr.nexthdr); | |
420 | } | |
421 | ||
422 | /* Hop Limit */ | |
4710d806 | 423 | if ((iphc0 & 0x03) != LOWPAN_IPHC_TTL_I) { |
8df8c56a | 424 | hdr.hop_limit = lowpan_ttl_values[iphc0 & 0x03]; |
4710d806 | 425 | } else { |
4ebc960f AA |
426 | if (lowpan_fetch_skb(skb, &hdr.hop_limit, |
427 | sizeof(hdr.hop_limit))) | |
56b2c3ee | 428 | return -EINVAL; |
8df8c56a JR |
429 | } |
430 | ||
431 | /* Extract SAM to the tmp variable */ | |
432 | tmp = ((iphc1 & LOWPAN_IPHC_SAM) >> LOWPAN_IPHC_SAM_BIT) & 0x03; | |
433 | ||
434 | if (iphc1 & LOWPAN_IPHC_SAC) { | |
435 | /* Source address context based uncompression */ | |
436 | pr_debug("SAC bit is set. Handle context based source address.\n"); | |
7fc4cfda | 437 | err = uncompress_context_based_src_addr(skb, &hdr.saddr, tmp); |
8df8c56a JR |
438 | } else { |
439 | /* Source address uncompression */ | |
440 | pr_debug("source address stateless compression\n"); | |
8911d774 | 441 | err = uncompress_addr(skb, dev, &hdr.saddr, tmp, saddr); |
8df8c56a JR |
442 | } |
443 | ||
444 | /* Check on error of previous branch */ | |
445 | if (err) | |
56b2c3ee | 446 | return -EINVAL; |
8df8c56a JR |
447 | |
448 | /* Extract DAM to the tmp variable */ | |
449 | tmp = ((iphc1 & LOWPAN_IPHC_DAM_11) >> LOWPAN_IPHC_DAM_BIT) & 0x03; | |
450 | ||
451 | /* check for Multicast Compression */ | |
452 | if (iphc1 & LOWPAN_IPHC_M) { | |
453 | if (iphc1 & LOWPAN_IPHC_DAC) { | |
454 | pr_debug("dest: context-based mcast compression\n"); | |
455 | /* TODO: implement this */ | |
456 | } else { | |
7fc4cfda MH |
457 | err = lowpan_uncompress_multicast_daddr(skb, &hdr.daddr, |
458 | tmp); | |
459 | ||
8df8c56a | 460 | if (err) |
56b2c3ee | 461 | return -EINVAL; |
8df8c56a JR |
462 | } |
463 | } else { | |
8911d774 | 464 | err = uncompress_addr(skb, dev, &hdr.daddr, tmp, daddr); |
8df8c56a | 465 | pr_debug("dest: stateless compression mode %d dest %pI6c\n", |
4710d806 | 466 | tmp, &hdr.daddr); |
8df8c56a | 467 | if (err) |
56b2c3ee | 468 | return -EINVAL; |
8df8c56a JR |
469 | } |
470 | ||
cc6ed268 | 471 | /* Next header data uncompression */ |
8df8c56a | 472 | if (iphc0 & LOWPAN_IPHC_NH_C) { |
cc6ed268 AA |
473 | err = lowpan_nhc_do_uncompression(skb, dev, &hdr); |
474 | if (err < 0) | |
11e3ff70 | 475 | return err; |
11e3ff70 MT |
476 | } else { |
477 | err = skb_cow(skb, sizeof(hdr)); | |
56b2c3ee | 478 | if (unlikely(err)) |
11e3ff70 | 479 | return err; |
8df8c56a JR |
480 | } |
481 | ||
72a5e6bb AA |
482 | switch (lowpan_priv(dev)->lltype) { |
483 | case LOWPAN_LLTYPE_IEEE802154: | |
484 | if (lowpan_802154_cb(skb)->d_size) | |
485 | hdr.payload_len = htons(lowpan_802154_cb(skb)->d_size - | |
486 | sizeof(struct ipv6hdr)); | |
487 | else | |
488 | hdr.payload_len = htons(skb->len); | |
489 | break; | |
490 | default: | |
491 | hdr.payload_len = htons(skb->len); | |
492 | break; | |
493 | } | |
8df8c56a JR |
494 | |
495 | pr_debug("skb headroom size = %d, data length = %d\n", | |
496 | skb_headroom(skb), skb->len); | |
497 | ||
498 | pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n\t" | |
499 | "nexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n", | |
500 | hdr.version, ntohs(hdr.payload_len), hdr.nexthdr, | |
501 | hdr.hop_limit, &hdr.daddr); | |
502 | ||
f8b36176 MT |
503 | skb_push(skb, sizeof(hdr)); |
504 | skb_reset_network_header(skb); | |
505 | skb_copy_to_linear_data(skb, &hdr, sizeof(hdr)); | |
8df8c56a | 506 | |
f8b36176 | 507 | raw_dump_table(__func__, "raw header dump", (u8 *)&hdr, sizeof(hdr)); |
8df8c56a | 508 | |
f8b36176 | 509 | return 0; |
8df8c56a | 510 | } |
01141234 | 511 | EXPORT_SYMBOL_GPL(lowpan_header_decompress); |
8df8c56a | 512 | |
84ca5e03 | 513 | static u8 lowpan_compress_addr_64(u8 **hc_ptr, u8 shift, |
4710d806 VB |
514 | const struct in6_addr *ipaddr, |
515 | const unsigned char *lladdr) | |
8df8c56a JR |
516 | { |
517 | u8 val = 0; | |
518 | ||
519 | if (is_addr_mac_addr_based(ipaddr, lladdr)) { | |
520 | val = 3; /* 0-bits */ | |
521 | pr_debug("address compression 0 bits\n"); | |
522 | } else if (lowpan_is_iid_16_bit_compressable(ipaddr)) { | |
523 | /* compress IID to 16 bits xxxx::XXXX */ | |
85c71240 | 524 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[7], 2); |
8df8c56a JR |
525 | val = 2; /* 16-bits */ |
526 | raw_dump_inline(NULL, "Compressed ipv6 addr is (16 bits)", | |
84ca5e03 | 527 | *hc_ptr - 2, 2); |
8df8c56a JR |
528 | } else { |
529 | /* do not compress IID => xxxx::IID */ | |
85c71240 | 530 | lowpan_push_hc_data(hc_ptr, &ipaddr->s6_addr16[4], 8); |
8df8c56a JR |
531 | val = 1; /* 64-bits */ |
532 | raw_dump_inline(NULL, "Compressed ipv6 addr is (64 bits)", | |
84ca5e03 | 533 | *hc_ptr - 8, 8); |
8df8c56a JR |
534 | } |
535 | ||
536 | return rol8(val, shift); | |
537 | } | |
538 | ||
a6f77389 AA |
539 | int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev, |
540 | const void *daddr, const void *saddr) | |
8df8c56a | 541 | { |
84ca5e03 | 542 | u8 tmp, iphc0, iphc1, *hc_ptr; |
8df8c56a | 543 | struct ipv6hdr *hdr; |
bf513fd6 | 544 | u8 head[LOWPAN_IPHC_MAX_HC_BUF_LEN] = {}; |
cc6ed268 | 545 | int ret, addr_type; |
8df8c56a | 546 | |
a6f77389 | 547 | if (skb->protocol != htons(ETH_P_IPV6)) |
8df8c56a JR |
548 | return -EINVAL; |
549 | ||
550 | hdr = ipv6_hdr(skb); | |
84ca5e03 | 551 | hc_ptr = head + 2; |
8df8c56a JR |
552 | |
553 | pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n" | |
554 | "\tnexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n", | |
4710d806 VB |
555 | hdr->version, ntohs(hdr->payload_len), hdr->nexthdr, |
556 | hdr->hop_limit, &hdr->daddr); | |
8df8c56a JR |
557 | |
558 | raw_dump_table(__func__, "raw skb network header dump", | |
4710d806 | 559 | skb_network_header(skb), sizeof(struct ipv6hdr)); |
8df8c56a | 560 | |
4710d806 | 561 | /* As we copy some bit-length fields, in the IPHC encoding bytes, |
8df8c56a JR |
562 | * we sometimes use |= |
563 | * If the field is 0, and the current bit value in memory is 1, | |
564 | * this does not work. We therefore reset the IPHC encoding here | |
565 | */ | |
566 | iphc0 = LOWPAN_DISPATCH_IPHC; | |
567 | iphc1 = 0; | |
568 | ||
569 | /* TODO: context lookup */ | |
570 | ||
a6f77389 AA |
571 | raw_dump_inline(__func__, "saddr", saddr, EUI64_ADDR_LEN); |
572 | raw_dump_inline(__func__, "daddr", daddr, EUI64_ADDR_LEN); | |
8df8c56a | 573 | |
7fc4cfda | 574 | raw_dump_table(__func__, "sending raw skb network uncompressed packet", |
4710d806 | 575 | skb->data, skb->len); |
8df8c56a | 576 | |
4710d806 | 577 | /* Traffic class, flow label |
8df8c56a JR |
578 | * If flow label is 0, compress it. If traffic class is 0, compress it |
579 | * We have to process both in the same time as the offset of traffic | |
580 | * class depends on the presence of version and flow label | |
581 | */ | |
582 | ||
84ca5e03 | 583 | /* hc format of TC is ECN | DSCP , original one is DSCP | ECN */ |
8df8c56a JR |
584 | tmp = (hdr->priority << 4) | (hdr->flow_lbl[0] >> 4); |
585 | tmp = ((tmp & 0x03) << 6) | (tmp >> 2); | |
586 | ||
587 | if (((hdr->flow_lbl[0] & 0x0F) == 0) && | |
4710d806 | 588 | (hdr->flow_lbl[1] == 0) && (hdr->flow_lbl[2] == 0)) { |
8df8c56a JR |
589 | /* flow label can be compressed */ |
590 | iphc0 |= LOWPAN_IPHC_FL_C; | |
591 | if ((hdr->priority == 0) && | |
4710d806 | 592 | ((hdr->flow_lbl[0] & 0xF0) == 0)) { |
8df8c56a JR |
593 | /* compress (elide) all */ |
594 | iphc0 |= LOWPAN_IPHC_TC_C; | |
595 | } else { | |
596 | /* compress only the flow label */ | |
84ca5e03 AA |
597 | *hc_ptr = tmp; |
598 | hc_ptr += 1; | |
8df8c56a JR |
599 | } |
600 | } else { | |
601 | /* Flow label cannot be compressed */ | |
602 | if ((hdr->priority == 0) && | |
4710d806 | 603 | ((hdr->flow_lbl[0] & 0xF0) == 0)) { |
8df8c56a JR |
604 | /* compress only traffic class */ |
605 | iphc0 |= LOWPAN_IPHC_TC_C; | |
84ca5e03 AA |
606 | *hc_ptr = (tmp & 0xc0) | (hdr->flow_lbl[0] & 0x0F); |
607 | memcpy(hc_ptr + 1, &hdr->flow_lbl[1], 2); | |
608 | hc_ptr += 3; | |
8df8c56a JR |
609 | } else { |
610 | /* compress nothing */ | |
84ca5e03 | 611 | memcpy(hc_ptr, hdr, 4); |
8df8c56a | 612 | /* replace the top byte with new ECN | DSCP format */ |
84ca5e03 AA |
613 | *hc_ptr = tmp; |
614 | hc_ptr += 4; | |
8df8c56a JR |
615 | } |
616 | } | |
617 | ||
618 | /* NOTE: payload length is always compressed */ | |
619 | ||
cc6ed268 AA |
620 | /* Check if we provide the nhc format for nexthdr and compression |
621 | * functionality. If not nexthdr is handled inline and not compressed. | |
622 | */ | |
607b0bd3 AA |
623 | ret = lowpan_nhc_check_compression(skb, hdr, &hc_ptr); |
624 | if (ret == -ENOENT) | |
625 | lowpan_push_hc_data(&hc_ptr, &hdr->nexthdr, | |
626 | sizeof(hdr->nexthdr)); | |
627 | else | |
628 | iphc0 |= LOWPAN_IPHC_NH_C; | |
8df8c56a | 629 | |
4710d806 | 630 | /* Hop limit |
8df8c56a JR |
631 | * if 1: compress, encoding is 01 |
632 | * if 64: compress, encoding is 10 | |
633 | * if 255: compress, encoding is 11 | |
634 | * else do not compress | |
635 | */ | |
636 | switch (hdr->hop_limit) { | |
637 | case 1: | |
638 | iphc0 |= LOWPAN_IPHC_TTL_1; | |
639 | break; | |
640 | case 64: | |
641 | iphc0 |= LOWPAN_IPHC_TTL_64; | |
642 | break; | |
643 | case 255: | |
644 | iphc0 |= LOWPAN_IPHC_TTL_255; | |
645 | break; | |
646 | default: | |
85c71240 AA |
647 | lowpan_push_hc_data(&hc_ptr, &hdr->hop_limit, |
648 | sizeof(hdr->hop_limit)); | |
8df8c56a JR |
649 | } |
650 | ||
556a5bfc | 651 | addr_type = ipv6_addr_type(&hdr->saddr); |
8df8c56a | 652 | /* source address compression */ |
556a5bfc | 653 | if (addr_type == IPV6_ADDR_ANY) { |
8df8c56a JR |
654 | pr_debug("source address is unspecified, setting SAC\n"); |
655 | iphc1 |= LOWPAN_IPHC_SAC; | |
8df8c56a | 656 | } else { |
556a5bfc AA |
657 | if (addr_type & IPV6_ADDR_LINKLOCAL) { |
658 | iphc1 |= lowpan_compress_addr_64(&hc_ptr, | |
659 | LOWPAN_IPHC_SAM_BIT, | |
a6f77389 | 660 | &hdr->saddr, saddr); |
556a5bfc AA |
661 | pr_debug("source address unicast link-local %pI6c iphc1 0x%02x\n", |
662 | &hdr->saddr, iphc1); | |
663 | } else { | |
664 | pr_debug("send the full source address\n"); | |
665 | lowpan_push_hc_data(&hc_ptr, hdr->saddr.s6_addr, 16); | |
666 | } | |
8df8c56a JR |
667 | } |
668 | ||
556a5bfc | 669 | addr_type = ipv6_addr_type(&hdr->daddr); |
8df8c56a | 670 | /* destination address compression */ |
556a5bfc | 671 | if (addr_type & IPV6_ADDR_MULTICAST) { |
8df8c56a JR |
672 | pr_debug("destination address is multicast: "); |
673 | iphc1 |= LOWPAN_IPHC_M; | |
674 | if (lowpan_is_mcast_addr_compressable8(&hdr->daddr)) { | |
675 | pr_debug("compressed to 1 octet\n"); | |
676 | iphc1 |= LOWPAN_IPHC_DAM_11; | |
677 | /* use last byte */ | |
85c71240 AA |
678 | lowpan_push_hc_data(&hc_ptr, |
679 | &hdr->daddr.s6_addr[15], 1); | |
8df8c56a JR |
680 | } else if (lowpan_is_mcast_addr_compressable32(&hdr->daddr)) { |
681 | pr_debug("compressed to 4 octets\n"); | |
682 | iphc1 |= LOWPAN_IPHC_DAM_10; | |
683 | /* second byte + the last three */ | |
85c71240 AA |
684 | lowpan_push_hc_data(&hc_ptr, |
685 | &hdr->daddr.s6_addr[1], 1); | |
686 | lowpan_push_hc_data(&hc_ptr, | |
687 | &hdr->daddr.s6_addr[13], 3); | |
8df8c56a JR |
688 | } else if (lowpan_is_mcast_addr_compressable48(&hdr->daddr)) { |
689 | pr_debug("compressed to 6 octets\n"); | |
690 | iphc1 |= LOWPAN_IPHC_DAM_01; | |
691 | /* second byte + the last five */ | |
85c71240 AA |
692 | lowpan_push_hc_data(&hc_ptr, |
693 | &hdr->daddr.s6_addr[1], 1); | |
694 | lowpan_push_hc_data(&hc_ptr, | |
695 | &hdr->daddr.s6_addr[11], 5); | |
8df8c56a JR |
696 | } else { |
697 | pr_debug("using full address\n"); | |
698 | iphc1 |= LOWPAN_IPHC_DAM_00; | |
85c71240 | 699 | lowpan_push_hc_data(&hc_ptr, hdr->daddr.s6_addr, 16); |
8df8c56a JR |
700 | } |
701 | } else { | |
556a5bfc AA |
702 | if (addr_type & IPV6_ADDR_LINKLOCAL) { |
703 | /* TODO: context lookup */ | |
84ca5e03 | 704 | iphc1 |= lowpan_compress_addr_64(&hc_ptr, |
a6f77389 | 705 | LOWPAN_IPHC_DAM_BIT, &hdr->daddr, daddr); |
8df8c56a | 706 | pr_debug("dest address unicast link-local %pI6c " |
7fc4cfda | 707 | "iphc1 0x%02x\n", &hdr->daddr, iphc1); |
8df8c56a JR |
708 | } else { |
709 | pr_debug("dest address unicast %pI6c\n", &hdr->daddr); | |
85c71240 | 710 | lowpan_push_hc_data(&hc_ptr, hdr->daddr.s6_addr, 16); |
8df8c56a JR |
711 | } |
712 | } | |
713 | ||
cc6ed268 AA |
714 | /* next header compression */ |
715 | if (iphc0 & LOWPAN_IPHC_NH_C) { | |
716 | ret = lowpan_nhc_do_compression(skb, hdr, &hc_ptr); | |
717 | if (ret < 0) | |
718 | return ret; | |
719 | } | |
8df8c56a JR |
720 | |
721 | head[0] = iphc0; | |
722 | head[1] = iphc1; | |
723 | ||
724 | skb_pull(skb, sizeof(struct ipv6hdr)); | |
725 | skb_reset_transport_header(skb); | |
84ca5e03 | 726 | memcpy(skb_push(skb, hc_ptr - head), head, hc_ptr - head); |
8df8c56a JR |
727 | skb_reset_network_header(skb); |
728 | ||
84ca5e03 | 729 | pr_debug("header len %d skb %u\n", (int)(hc_ptr - head), skb->len); |
8df8c56a JR |
730 | |
731 | raw_dump_table(__func__, "raw skb data dump compressed", | |
4710d806 | 732 | skb->data, skb->len); |
8df8c56a JR |
733 | return 0; |
734 | } | |
735 | EXPORT_SYMBOL_GPL(lowpan_header_compress); |