1 /**
2 * @file
3 *
4 * 6LowPAN output for IPv6. Uses ND tables for link-layer addressing. Fragments packets to 6LowPAN units.
5 */
6
7 /*
8 * Copyright (c) 2015 Inico Technologies Ltd.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without modification,
12 * are permitted provided that the following conditions are met:
13 *
14 * 1. Redistributions of source code must retain the above copyright notice,
15 * this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright notice,
17 * this list of conditions and the following disclaimer in the documentation
18 * and/or other materials provided with the distribution.
19 * 3. The name of the author may not be used to endorse or promote products
20 * derived from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
25 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
26 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
27 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
30 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
31 * OF SUCH DAMAGE.
32 *
33 * This file is part of the lwIP TCP/IP stack.
34 *
35 * Author: Ivan Delamer <[email protected]>
36 *
37 *
38 * Please coordinate changes and requests with Ivan Delamer
39 * <[email protected]>
40 */
41
42 /**
43 * @defgroup sixlowpan 6LowPAN netif
44 * @ingroup addons
45 * 6LowPAN netif implementation
46 */
47
48 #include "netif/lowpan6.h"
49
50 #if LWIP_IPV6 && LWIP_6LOWPAN
51
52 #include "lwip/ip.h"
53 #include "lwip/pbuf.h"
54 #include "lwip/ip_addr.h"
55 #include "lwip/netif.h"
56 #include "lwip/nd6.h"
57 #include "lwip/mem.h"
58 #include "lwip/udp.h"
59 #include "lwip/tcpip.h"
60 #include "lwip/snmp.h"
61
62 #include <string.h>
63
64 struct ieee_802154_addr {
65 u8_t addr_len;
66 u8_t addr[8];
67 };
68
69 /** This is a helper struct.
70 */
71 struct lowpan6_reass_helper {
72 struct pbuf *pbuf;
73 struct lowpan6_reass_helper *next_packet;
74 u8_t timer;
75 struct ieee_802154_addr sender_addr;
76 u16_t datagram_size;
77 u16_t datagram_tag;
78 };
79
80 static struct lowpan6_reass_helper * reass_list;
81
82 #if LWIP_6LOWPAN_NUM_CONTEXTS > 0
83 static ip6_addr_t lowpan6_context[LWIP_6LOWPAN_NUM_CONTEXTS];
84 #endif
85
86 static u16_t ieee_802154_pan_id;
87
88 static const struct ieee_802154_addr ieee_802154_broadcast = {2, {0xff, 0xff}};
89
90 #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
91 static struct ieee_802154_addr short_mac_addr = {2, {0,0}};
92 #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
93
94 static err_t dequeue_datagram(struct lowpan6_reass_helper *lrh);
95
96 /**
97 * Periodic timer for 6LowPAN functions:
98 *
99 * - Remove incomplete/old packets
100 */
101 void
lowpan6_tmr(void)102 lowpan6_tmr(void)
103 {
104 struct lowpan6_reass_helper *lrh, *lrh_temp;
105
106 lrh = reass_list;
107 while (lrh != NULL) {
108 lrh_temp = lrh->next_packet;
109 if ((--lrh->timer) == 0) {
110 dequeue_datagram(lrh);
111 pbuf_free(lrh->pbuf);
112 mem_free(lrh);
113 }
114 lrh = lrh_temp;
115 }
116 }
117
118 /**
119 * Removes a datagram from the reassembly queue.
120 **/
121 static err_t
dequeue_datagram(struct lowpan6_reass_helper * lrh)122 dequeue_datagram(struct lowpan6_reass_helper *lrh)
123 {
124 struct lowpan6_reass_helper *lrh_temp;
125
126 if (reass_list == lrh) {
127 reass_list = reass_list->next_packet;
128 } else {
129 lrh_temp = reass_list;
130 while (lrh_temp != NULL) {
131 if (lrh_temp->next_packet == lrh) {
132 lrh_temp->next_packet = lrh->next_packet;
133 break;
134 }
135 lrh_temp = lrh_temp->next_packet;
136 }
137 }
138
139 return ERR_OK;
140 }
141
142 static s8_t
lowpan6_context_lookup(const ip6_addr_t * ip6addr)143 lowpan6_context_lookup(const ip6_addr_t *ip6addr)
144 {
145 s8_t i;
146
147 for (i = 0; i < LWIP_6LOWPAN_NUM_CONTEXTS; i++) {
148 if (ip6_addr_netcmp(&lowpan6_context[i], ip6addr)) {
149 return i;
150 }
151 }
152
153 return -1;
154 }
155
156 /* Determine compression mode for unicast address. */
157 static s8_t
lowpan6_get_address_mode(const ip6_addr_t * ip6addr,const struct ieee_802154_addr * mac_addr)158 lowpan6_get_address_mode(const ip6_addr_t *ip6addr, const struct ieee_802154_addr *mac_addr)
159 {
160 if (mac_addr->addr_len == 2) {
161 if ((ip6addr->addr[2] == (u32_t)PP_HTONL(0x000000ff)) &&
162 ((ip6addr->addr[3] & PP_HTONL(0xffff0000)) == PP_NTOHL(0xfe000000))) {
163 if ((ip6addr->addr[3] & PP_HTONL(0x0000ffff)) == lwip_ntohl((mac_addr->addr[0] << 8) | mac_addr->addr[1])) {
164 return 3;
165 }
166 }
167 } else if (mac_addr->addr_len == 8) {
168 if ((ip6addr->addr[2] == lwip_ntohl(((mac_addr->addr[0] ^ 2) << 24) | (mac_addr->addr[1] << 16) | mac_addr->addr[2] << 8 | mac_addr->addr[3])) &&
169 (ip6addr->addr[3] == lwip_ntohl((mac_addr->addr[4] << 24) | (mac_addr->addr[5] << 16) | mac_addr->addr[6] << 8 | mac_addr->addr[7]))) {
170 return 3;
171 }
172 }
173
174 if ((ip6addr->addr[2] == PP_HTONL(0x000000ffUL)) &&
175 ((ip6addr->addr[3] & PP_HTONL(0xffff0000)) == PP_NTOHL(0xfe000000UL))) {
176 return 2;
177 }
178
179 return 1;
180 }
181
182 /* Determine compression mode for multicast address. */
183 static s8_t
lowpan6_get_address_mode_mc(const ip6_addr_t * ip6addr)184 lowpan6_get_address_mode_mc(const ip6_addr_t *ip6addr)
185 {
186 if ((ip6addr->addr[0] == PP_HTONL(0xff020000)) &&
187 (ip6addr->addr[1] == 0) &&
188 (ip6addr->addr[2] == 0) &&
189 ((ip6addr->addr[3] & PP_HTONL(0xffffff00)) == 0)) {
190 return 3;
191 } else if (((ip6addr->addr[0] & PP_HTONL(0xff00ffff)) == PP_HTONL(0xff000000)) &&
192 (ip6addr->addr[1] == 0)) {
193 if ((ip6addr->addr[2] == 0) &&
194 ((ip6addr->addr[3] & PP_HTONL(0xff000000)) == 0)) {
195 return 2;
196 } else if ((ip6addr->addr[2] & PP_HTONL(0xffffff00)) == 0) {
197 return 1;
198 }
199 }
200
201 return 0;
202 }
203
204 /*
205 * Encapsulates data into IEEE 802.15.4 frames.
206 * Fragments an IPv6 datagram into 6LowPAN units, which fit into IEEE 802.15.4 frames.
207 * If configured, will compress IPv6 and or UDP headers.
208 * */
209 static err_t
lowpan6_frag(struct netif * netif,struct pbuf * p,const struct ieee_802154_addr * src,const struct ieee_802154_addr * dst)210 lowpan6_frag(struct netif *netif, struct pbuf *p, const struct ieee_802154_addr *src, const struct ieee_802154_addr *dst)
211 {
212 struct pbuf * p_frag;
213 u16_t frag_len, remaining_len;
214 u8_t * buffer;
215 u8_t ieee_header_len;
216 u8_t lowpan6_header_len;
217 s8_t i;
218 static u8_t frame_seq_num;
219 static u16_t datagram_tag;
220 u16_t datagram_offset;
221 err_t err = ERR_IF;
222
223 /* We'll use a dedicated pbuf for building 6LowPAN fragments. */
224 p_frag = pbuf_alloc(PBUF_RAW, 127, PBUF_RAM);
225 if (p_frag == NULL) {
226 MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
227 return ERR_MEM;
228 }
229
230 /* Write IEEE 802.15.4 header. */
231 buffer = (u8_t*)p_frag->payload;
232 ieee_header_len = 0;
233 if (dst == &ieee_802154_broadcast) {
234 buffer[ieee_header_len++] = 0x01; /* data packet, no ack required. */
235 } else {
236 buffer[ieee_header_len++] = 0x21; /* data packet, ack required. */
237 }
238 buffer[ieee_header_len] = (0x00 << 4); /* 2003 frame version */
239 buffer[ieee_header_len] |= (dst->addr_len == 2) ? (0x02 << 2) : (0x03 << 2); /* destination addressing mode */
240 buffer[ieee_header_len] |= (src->addr_len == 2) ? (0x02 << 6) : (0x03 << 6); /* source addressing mode */
241 ieee_header_len++;
242 buffer[ieee_header_len++] = frame_seq_num++;
243
244 buffer[ieee_header_len++] = ieee_802154_pan_id & 0xff; /* pan id */
245 buffer[ieee_header_len++] = (ieee_802154_pan_id >> 8) & 0xff; /* pan id */
246 i = dst->addr_len;
247 while (i-- > 0) {
248 buffer[ieee_header_len++] = dst->addr[i];
249 }
250
251 buffer[ieee_header_len++] = ieee_802154_pan_id & 0xff; /* pan id */
252 buffer[ieee_header_len++] = (ieee_802154_pan_id >> 8) & 0xff; /* pan id */
253 i = src->addr_len;
254 while (i-- > 0) {
255 buffer[ieee_header_len++] = src->addr[i];
256 }
257
258 #if LWIP_6LOWPAN_IPHC
259 /* Perform 6LowPAN IPv6 header compression according to RFC 6282 */
260 {
261 struct ip6_hdr *ip6hdr;
262
263 /* Point to ip6 header and align copies of src/dest addresses. */
264 ip6hdr = (struct ip6_hdr *)p->payload;
265 ip_addr_copy_from_ip6(ip_data.current_iphdr_dest, ip6hdr->dest);
266 ip_addr_copy_from_ip6(ip_data.current_iphdr_src, ip6hdr->src);
267
268 /* Basic length of 6LowPAN header, set dispatch and clear fields. */
269 lowpan6_header_len = 2;
270 buffer[ieee_header_len] = 0x60;
271 buffer[ieee_header_len + 1] = 0;
272
273 /* Determine whether there will be a Context Identifier Extension byte or not.
274 * If so, set it already. */
275 #if LWIP_6LOWPAN_NUM_CONTEXTS > 0
276 buffer[ieee_header_len + 2] = 0;
277
278 i = lowpan6_context_lookup(ip_2_ip6(&ip_data.current_iphdr_src));
279 if (i >= 0) {
280 /* Stateful source address compression. */
281 buffer[ieee_header_len + 1] |= 0x40;
282 buffer[ieee_header_len + 2] |= (i & 0x0f) << 4;
283 }
284
285 i = lowpan6_context_lookup(ip_2_ip6(&ip_data.current_iphdr_dest));
286 if (i >= 0) {
287 /* Stateful destination address compression. */
288 buffer[ieee_header_len + 1] |= 0x04;
289 buffer[ieee_header_len + 2] |= i & 0x0f;
290 }
291
292 if (buffer[ieee_header_len + 2] != 0x00) {
293 /* Context identifier extension byte is appended. */
294 buffer[ieee_header_len + 1] |= 0x80;
295 lowpan6_header_len++;
296 }
297 #endif /* LWIP_6LOWPAN_NUM_CONTEXTS > 0 */
298
299 /* Determine TF field: Traffic Class, Flow Label */
300 if (IP6H_FL(ip6hdr) == 0) {
301 /* Flow label is elided. */
302 buffer[ieee_header_len] |= 0x10;
303 if (IP6H_TC(ip6hdr) == 0) {
304 /* Traffic class (ECN+DSCP) elided too. */
305 buffer[ieee_header_len] |= 0x08;
306 } else {
307 /* Traffic class (ECN+DSCP) appended. */
308 buffer[ieee_header_len + lowpan6_header_len++] = IP6H_TC(ip6hdr);
309 }
310 } else {
311 if (((IP6H_TC(ip6hdr) & 0x3f) == 0)) {
312 /* DSCP portion of Traffic Class is elided, ECN and FL are appended (3 bytes) */
313 buffer[ieee_header_len] |= 0x08;
314
315 buffer[ieee_header_len + lowpan6_header_len] = IP6H_TC(ip6hdr) & 0xc0;
316 buffer[ieee_header_len + lowpan6_header_len++] |= (IP6H_FL(ip6hdr) >> 16) & 0x0f;
317 buffer[ieee_header_len + lowpan6_header_len++] = (IP6H_FL(ip6hdr) >> 8) & 0xff;
318 buffer[ieee_header_len + lowpan6_header_len++] = IP6H_FL(ip6hdr) & 0xff;
319 } else {
320 /* Traffic class and flow label are appended (4 bytes) */
321 buffer[ieee_header_len + lowpan6_header_len++] = IP6H_TC(ip6hdr);
322 buffer[ieee_header_len + lowpan6_header_len++] = (IP6H_FL(ip6hdr) >> 16) & 0x0f;
323 buffer[ieee_header_len + lowpan6_header_len++] = (IP6H_FL(ip6hdr) >> 8) & 0xff;
324 buffer[ieee_header_len + lowpan6_header_len++] = IP6H_FL(ip6hdr) & 0xff;
325 }
326 }
327
328 /* Compress NH?
329 * Only if UDP for now. @todo support other NH compression. */
330 if (IP6H_NEXTH(ip6hdr) == IP6_NEXTH_UDP) {
331 buffer[ieee_header_len] |= 0x04;
332 } else {
333 /* append nexth. */
334 buffer[ieee_header_len + lowpan6_header_len++] = IP6H_NEXTH(ip6hdr);
335 }
336
337 /* Compress hop limit? */
338 if (IP6H_HOPLIM(ip6hdr) == 255) {
339 buffer[ieee_header_len] |= 0x03;
340 } else if (IP6H_HOPLIM(ip6hdr) == 64) {
341 buffer[ieee_header_len] |= 0x02;
342 } else if (IP6H_HOPLIM(ip6hdr) == 1) {
343 buffer[ieee_header_len] |= 0x01;
344 } else {
345 /* append hop limit */
346 buffer[ieee_header_len + lowpan6_header_len++] = IP6H_HOPLIM(ip6hdr);
347 }
348
349 /* Compress source address */
350 if (((buffer[ieee_header_len + 1] & 0x40) != 0) ||
351 (ip6_addr_islinklocal(ip_2_ip6(&ip_data.current_iphdr_src)))) {
352 /* Context-based or link-local source address compression. */
353 i = lowpan6_get_address_mode(ip_2_ip6(&ip_data.current_iphdr_src), src);
354 buffer[ieee_header_len + 1] |= (i & 0x03) << 4;
355 if (i == 1) {
356 MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 16, 8);
357 lowpan6_header_len += 8;
358 } else if (i == 2) {
359 MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 22, 2);
360 lowpan6_header_len += 2;
361 }
362 } else if (ip6_addr_isany(ip_2_ip6(&ip_data.current_iphdr_src))) {
363 /* Special case: mark SAC and leave SAM=0 */
364 buffer[ieee_header_len + 1] |= 0x40;
365 } else {
366 /* Append full address. */
367 MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 8, 16);
368 lowpan6_header_len += 16;
369 }
370
371 /* Compress destination address */
372 if (ip6_addr_ismulticast(ip_2_ip6(&ip_data.current_iphdr_dest))) {
373 /* @todo support stateful multicast address compression */
374
375 buffer[ieee_header_len + 1] |= 0x08;
376
377 i = lowpan6_get_address_mode_mc(ip_2_ip6(&ip_data.current_iphdr_dest));
378 buffer[ieee_header_len + 1] |= i & 0x03;
379 if (i == 0) {
380 MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 24, 16);
381 lowpan6_header_len += 16;
382 } else if (i == 1) {
383 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[25];
384 MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 35, 5);
385 lowpan6_header_len += 5;
386 } else if (i == 2) {
387 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[25];
388 MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 37, 3);
389 lowpan6_header_len += 3;
390 } else if (i == 3) {
391 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[39];
392 }
393 } else if (((buffer[ieee_header_len + 1] & 0x04) != 0) ||
394 (ip6_addr_islinklocal(ip_2_ip6(&ip_data.current_iphdr_dest)))) {
395 /* Context-based or link-local destination address compression. */
396 i = lowpan6_get_address_mode(ip_2_ip6(&ip_data.current_iphdr_dest), dst);
397 buffer[ieee_header_len + 1] |= i & 0x03;
398 if (i == 1) {
399 MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 32, 8);
400 lowpan6_header_len += 8;
401 } else if (i == 2) {
402 MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 38, 2);
403 lowpan6_header_len += 2;
404 }
405 } else {
406 /* Append full address. */
407 MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 24, 16);
408 lowpan6_header_len += 16;
409 }
410
411 /* Move to payload. */
412 pbuf_header(p, -IP6_HLEN);
413
414 /* Compress UDP header? */
415 if (IP6H_NEXTH(ip6hdr) == IP6_NEXTH_UDP) {
416 /* @todo support optional checksum compression */
417
418 buffer[ieee_header_len + lowpan6_header_len] = 0xf0;
419
420 /* determine port compression mode. */
421 if ((((u8_t *)p->payload)[0] == 0xf0) && ((((u8_t *)p->payload)[1] & 0xf0) == 0xb0) &&
422 (((u8_t *)p->payload)[2] == 0xf0) && ((((u8_t *)p->payload)[3] & 0xf0) == 0xb0)) {
423 /* Compress source and dest ports. */
424 buffer[ieee_header_len + lowpan6_header_len++] |= 0x03;
425 buffer[ieee_header_len + lowpan6_header_len++] = ((((u8_t *)p->payload)[1] & 0x0f) << 4) | (((u8_t *)p->payload)[3] & 0x0f);
426 } else if (((u8_t *)p->payload)[0] == 0xf0) {
427 /* Compress source port. */
428 buffer[ieee_header_len + lowpan6_header_len++] |= 0x02;
429 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[1];
430 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[2];
431 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[3];
432 } else if (((u8_t *)p->payload)[2] == 0xf0) {
433 /* Compress dest port. */
434 buffer[ieee_header_len + lowpan6_header_len++] |= 0x01;
435 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[0];
436 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[1];
437 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[3];
438 } else {
439 /* append full ports. */
440 lowpan6_header_len++;
441 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[0];
442 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[1];
443 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[2];
444 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[3];
445 }
446
447 /* elide length and copy checksum */
448 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[6];
449 buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[7];
450
451 pbuf_header(p, -UDP_HLEN);
452 }
453 }
454
455 #else /* LWIP_6LOWPAN_HC */
456 /* Send uncompressed IPv6 header with appropriate dispatch byte. */
457 lowpan6_header_len = 1;
458 buffer[ieee_header_len] = 0x41; /* IPv6 dispatch */
459 #endif /* LWIP_6LOWPAN_HC */
460
461 /* Calculate remaining packet length */
462 remaining_len = p->tot_len;
463
464 if (remaining_len > 0x7FF) {
465 MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
466 /* datagram_size must fit into 11 bit */
467 pbuf_free(p_frag);
468 return ERR_VAL;
469 }
470
471 /* Fragment, or 1 packet? */
472 if (remaining_len > (127 - ieee_header_len - lowpan6_header_len - 3)) { /* 127 - header - 1 byte dispatch - 2 bytes CRC */
473 /* We must move the 6LowPAN header to make room for the FRAG header. */
474 i = lowpan6_header_len;
475 while (i-- != 0) {
476 buffer[ieee_header_len + i + 4] = buffer[ieee_header_len + i];
477 }
478
479 /* Now we need to fragment the packet. FRAG1 header first */
480 buffer[ieee_header_len] = 0xc0 | (((p->tot_len + lowpan6_header_len) >> 8) & 0x7);
481 buffer[ieee_header_len + 1] = (p->tot_len + lowpan6_header_len) & 0xff;
482
483 datagram_tag++;
484 buffer[ieee_header_len + 2] = datagram_tag & 0xff;
485 buffer[ieee_header_len + 3] = (datagram_tag >> 8) & 0xff;
486
487 /* Fragment follows. */
488 frag_len = (127 - ieee_header_len - 4 - 2) & 0xf8;
489
490 pbuf_copy_partial(p, buffer + ieee_header_len + lowpan6_header_len + 4, frag_len - lowpan6_header_len, 0);
491 remaining_len -= frag_len - lowpan6_header_len;
492 datagram_offset = frag_len;
493
494 /* 2 bytes CRC */
495 #if LWIP_6LOWPAN_HW_CRC
496 /* Leave blank, will be filled by HW. */
497 #else /* LWIP_6LOWPAN_HW_CRC */
498 /* @todo calculate CRC */
499 #endif /* LWIP_6LOWPAN_HW_CRC */
500
501 /* Calculate frame length */
502 p_frag->len = p_frag->tot_len = ieee_header_len + 4 + frag_len + 2; /* add 2 dummy bytes for crc*/
503
504 /* send the packet */
505 MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p_frag->tot_len);
506 LWIP_DEBUGF(LOWPAN6_DEBUG | LWIP_DBG_TRACE, ("lowpan6_send: sending packet %p\n", (void *)p));
507 err = netif->linkoutput(netif, p_frag);
508
509 while ((remaining_len > 0) && (err == ERR_OK)) {
510 /* new frame, new seq num for ACK */
511 buffer[2] = frame_seq_num++;
512
513 buffer[ieee_header_len] |= 0x20; /* Change FRAG1 to FRAGN */
514
515 buffer[ieee_header_len + 4] = (u8_t)(datagram_offset >> 3); /* datagram offset in FRAGN header (datagram_offset is max. 11 bit) */
516
517 frag_len = (127 - ieee_header_len - 5 - 2) & 0xf8;
518 if (frag_len > remaining_len) {
519 frag_len = remaining_len;
520 }
521
522 pbuf_copy_partial(p, buffer + ieee_header_len + 5, frag_len, p->tot_len - remaining_len);
523 remaining_len -= frag_len;
524 datagram_offset += frag_len;
525
526 /* 2 bytes CRC */
527 #if LWIP_6LOWPAN_HW_CRC
528 /* Leave blank, will be filled by HW. */
529 #else /* LWIP_6LOWPAN_HW_CRC */
530 /* @todo calculate CRC */
531 #endif /* LWIP_6LOWPAN_HW_CRC */
532
533 /* Calculate frame length */
534 p_frag->len = p_frag->tot_len = frag_len + 5 + ieee_header_len + 2;
535
536 /* send the packet */
537 MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p_frag->tot_len);
538 LWIP_DEBUGF(LOWPAN6_DEBUG | LWIP_DBG_TRACE, ("lowpan6_send: sending packet %p\n", (void *)p));
539 err = netif->linkoutput(netif, p_frag);
540 }
541 } else {
542 /* It fits in one frame. */
543 frag_len = remaining_len;
544
545 /* Copy IPv6 packet */
546 pbuf_copy_partial(p, buffer + ieee_header_len + lowpan6_header_len, frag_len, 0);
547 remaining_len = 0;
548
549 /* 2 bytes CRC */
550 #if LWIP_6LOWPAN_HW_CRC
551 /* Leave blank, will be filled by HW. */
552 #else /* LWIP_6LOWPAN_HW_CRC */
553 /* @todo calculate CRC */
554 #endif /* LWIP_6LOWPAN_HW_CRC */
555
556 /* Calculate frame length */
557 p_frag->len = p_frag->tot_len = frag_len + lowpan6_header_len + ieee_header_len + 2;
558
559 /* send the packet */
560 MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p_frag->tot_len);
561 LWIP_DEBUGF(LOWPAN6_DEBUG | LWIP_DBG_TRACE, ("lowpan6_send: sending packet %p\n", (void *)p));
562 err = netif->linkoutput(netif, p_frag);
563 }
564
565 pbuf_free(p_frag);
566
567 return err;
568 }
569
570 err_t
lowpan6_set_context(u8_t idx,const ip6_addr_t * context)571 lowpan6_set_context(u8_t idx, const ip6_addr_t * context)
572 {
573 if (idx >= LWIP_6LOWPAN_NUM_CONTEXTS) {
574 return ERR_ARG;
575 }
576
577 ip6_addr_set(&lowpan6_context[idx], context);
578
579 return ERR_OK;
580 }
581
582 #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
583 err_t
lowpan6_set_short_addr(u8_t addr_high,u8_t addr_low)584 lowpan6_set_short_addr(u8_t addr_high, u8_t addr_low)
585 {
586 short_mac_addr.addr[0] = addr_high;
587 short_mac_addr.addr[1] = addr_low;
588
589 return ERR_OK;
590 }
591 #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
592
593 #if LWIP_IPV4
594 err_t
lowpan4_output(struct netif * netif,struct pbuf * q,const ip4_addr_t * ipaddr)595 lowpan4_output(struct netif *netif, struct pbuf *q, const ip4_addr_t *ipaddr)
596 {
597 (void)netif;
598 (void)q;
599 (void)ipaddr;
600
601 return ERR_IF;
602 }
603 #endif /* LWIP_IPV4 */
604
605 /**
606 * Resolve and fill-in IEEE 802.15.4 address header for outgoing IPv6 packet.
607 *
608 * Perform Header Compression and fragment if necessary.
609 *
610 * @param netif The lwIP network interface which the IP packet will be sent on.
611 * @param q The pbuf(s) containing the IP packet to be sent.
612 * @param ip6addr The IP address of the packet destination.
613 *
614 * @return err_t
615 */
616 err_t
lowpan6_output(struct netif * netif,struct pbuf * q,const ip6_addr_t * ip6addr)617 lowpan6_output(struct netif *netif, struct pbuf *q, const ip6_addr_t *ip6addr)
618 {
619 err_t result;
620 const u8_t *hwaddr;
621 struct ieee_802154_addr src, dest;
622 #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
623 ip6_addr_t ip6_src;
624 struct ip6_hdr * ip6_hdr;
625 #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
626
627 #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
628 /* Check if we can compress source address (use aligned copy) */
629 ip6_hdr = (struct ip6_hdr *)q->payload;
630 ip6_addr_set(&ip6_src, &ip6_hdr->src);
631 if (lowpan6_get_address_mode(&ip6_src, &short_mac_addr) == 3) {
632 src.addr_len = 2;
633 src.addr[0] = short_mac_addr.addr[0];
634 src.addr[1] = short_mac_addr.addr[1];
635 } else
636 #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
637 {
638 src.addr_len = netif->hwaddr_len;
639 SMEMCPY(src.addr, netif->hwaddr, netif->hwaddr_len);
640 }
641
642 /* multicast destination IP address? */
643 if (ip6_addr_ismulticast(ip6addr)) {
644 MIB2_STATS_NETIF_INC(netif, ifoutnucastpkts);
645 /* We need to send to the broadcast address.*/
646 return lowpan6_frag(netif, q, &src, &ieee_802154_broadcast);
647 }
648
649 /* We have a unicast destination IP address */
650 /* @todo anycast? */
651
652 #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
653 if (src.addr_len == 2) {
654 /* If source address was compressable to short_mac_addr, and dest has same subnet and
655 * is also compressable to 2-bytes, assume we can infer dest as a short address too. */
656 dest.addr_len = 2;
657 dest.addr[0] = ((u8_t *)q->payload)[38];
658 dest.addr[1] = ((u8_t *)q->payload)[39];
659 if ((src.addr_len == 2) && (ip6_addr_netcmp(&ip6_hdr->src, &ip6_hdr->dest)) &&
660 (lowpan6_get_address_mode(ip6addr, &dest) == 3)) {
661 MIB2_STATS_NETIF_INC(netif, ifoutucastpkts);
662 return lowpan6_frag(netif, q, &src, &dest);
663 }
664 }
665 #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
666
667 /* Ask ND6 what to do with the packet. */
668 result = nd6_get_next_hop_addr_or_queue(netif, q, ip6addr, &hwaddr);
669 if (result != ERR_OK) {
670 MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
671 return result;
672 }
673
674 /* If no hardware address is returned, nd6 has queued the packet for later. */
675 if (hwaddr == NULL) {
676 return ERR_OK;
677 }
678
679 /* Send out the packet using the returned hardware address. */
680 dest.addr_len = netif->hwaddr_len;
681 SMEMCPY(dest.addr, hwaddr, netif->hwaddr_len);
682 MIB2_STATS_NETIF_INC(netif, ifoutucastpkts);
683 return lowpan6_frag(netif, q, &src, &dest);
684 }
685
686 static struct pbuf *
lowpan6_decompress(struct pbuf * p,struct ieee_802154_addr * src,struct ieee_802154_addr * dest)687 lowpan6_decompress(struct pbuf * p, struct ieee_802154_addr * src, struct ieee_802154_addr * dest)
688 {
689 struct pbuf * q;
690 u8_t * lowpan6_buffer;
691 s8_t lowpan6_offset;
692 struct ip6_hdr *ip6hdr;
693 s8_t i;
694 s8_t ip6_offset = IP6_HLEN;
695
696
697 q = pbuf_alloc(PBUF_IP, p->len + IP6_HLEN + UDP_HLEN, PBUF_POOL);
698 if (q == NULL) {
699 pbuf_free(p);
700 return NULL;
701 }
702
703 lowpan6_buffer = (u8_t *)p->payload;
704 ip6hdr = (struct ip6_hdr *)q->payload;
705
706 lowpan6_offset = 2;
707 if (lowpan6_buffer[1] & 0x80) {
708 lowpan6_offset++;
709 }
710
711 /* Set IPv6 version, traffic class and flow label. */
712 if ((lowpan6_buffer[0] & 0x18) == 0x00) {
713 IP6H_VTCFL_SET(ip6hdr, 6, lowpan6_buffer[lowpan6_offset], ((lowpan6_buffer[lowpan6_offset+1] & 0x0f) << 16) | (lowpan6_buffer[lowpan6_offset + 2] << 8) | lowpan6_buffer[lowpan6_offset+3]);
714 lowpan6_offset += 4;
715 } else if ((lowpan6_buffer[0] & 0x18) == 0x08) {
716 IP6H_VTCFL_SET(ip6hdr, 6, lowpan6_buffer[lowpan6_offset] & 0xc0, ((lowpan6_buffer[lowpan6_offset] & 0x0f) << 16) | (lowpan6_buffer[lowpan6_offset + 1] << 8) | lowpan6_buffer[lowpan6_offset+2]);
717 lowpan6_offset += 3;
718 } else if ((lowpan6_buffer[0] & 0x18) == 0x10) {
719 IP6H_VTCFL_SET(ip6hdr, 6, lowpan6_buffer[lowpan6_offset],0);
720 lowpan6_offset += 1;
721 } else if ((lowpan6_buffer[0] & 0x18) == 0x18) {
722 IP6H_VTCFL_SET(ip6hdr, 6, 0, 0);
723 }
724
725 /* Set Next Header */
726 if ((lowpan6_buffer[0] & 0x04) == 0x00) {
727 IP6H_NEXTH_SET(ip6hdr, lowpan6_buffer[lowpan6_offset++]);
728 } else {
729 /* We should fill this later with NHC decoding */
730 IP6H_NEXTH_SET(ip6hdr, 0);
731 }
732
733 /* Set Hop Limit */
734 if ((lowpan6_buffer[0] & 0x03) == 0x00) {
735 IP6H_HOPLIM_SET(ip6hdr, lowpan6_buffer[lowpan6_offset++]);
736 } else if ((lowpan6_buffer[0] & 0x03) == 0x01) {
737 IP6H_HOPLIM_SET(ip6hdr, 1);
738 } else if ((lowpan6_buffer[0] & 0x03) == 0x02) {
739 IP6H_HOPLIM_SET(ip6hdr, 64);
740 } else if ((lowpan6_buffer[0] & 0x03) == 0x03) {
741 IP6H_HOPLIM_SET(ip6hdr, 255);
742 }
743
744 /* Source address decoding. */
745 if ((lowpan6_buffer[1] & 0x40) == 0x00) {
746 /* Stateless compression */
747 if ((lowpan6_buffer[1] & 0x30) == 0x00) {
748 /* copy full address */
749 MEMCPY(&ip6hdr->src.addr[0], lowpan6_buffer + lowpan6_offset, 16);
750 lowpan6_offset += 16;
751 } else if ((lowpan6_buffer[1] & 0x30) == 0x10) {
752 ip6hdr->src.addr[0] = PP_HTONL(0xfe800000UL);
753 ip6hdr->src.addr[1] = 0;
754 MEMCPY(&ip6hdr->src.addr[2], lowpan6_buffer + lowpan6_offset, 8);
755 lowpan6_offset += 8;
756 } else if ((lowpan6_buffer[1] & 0x30) == 0x20) {
757 ip6hdr->src.addr[0] = PP_HTONL(0xfe800000UL);
758 ip6hdr->src.addr[1] = 0;
759 ip6hdr->src.addr[2] = PP_HTONL(0x000000ffUL);
760 ip6hdr->src.addr[3] = lwip_htonl(0xfe000000UL | (lowpan6_buffer[lowpan6_offset] << 8) |
761 lowpan6_buffer[lowpan6_offset+1]);
762 lowpan6_offset += 2;
763 } else if ((lowpan6_buffer[1] & 0x30) == 0x30) {
764 ip6hdr->src.addr[0] = PP_HTONL(0xfe800000UL);
765 ip6hdr->src.addr[1] = 0;
766 if (src->addr_len == 2) {
767 ip6hdr->src.addr[2] = PP_HTONL(0x000000ffUL);
768 ip6hdr->src.addr[3] = lwip_htonl(0xfe000000UL | (src->addr[0] << 8) | src->addr[1]);
769 } else {
770 ip6hdr->src.addr[2] = lwip_htonl(((src->addr[0] ^ 2) << 24) | (src->addr[1] << 16) |
771 (src->addr[2] << 8) | src->addr[3]);
772 ip6hdr->src.addr[3] = lwip_htonl((src->addr[4] << 24) | (src->addr[5] << 16) |
773 (src->addr[6] << 8) | src->addr[7]);
774 }
775 }
776 } else {
777 /* Stateful compression */
778 if ((lowpan6_buffer[1] & 0x30) == 0x00) {
779 /* ANY address */
780 ip6hdr->src.addr[0] = 0;
781 ip6hdr->src.addr[1] = 0;
782 ip6hdr->src.addr[2] = 0;
783 ip6hdr->src.addr[3] = 0;
784 } else {
785 /* Set prefix from context info */
786 if (lowpan6_buffer[1] & 0x80) {
787 i = (lowpan6_buffer[2] >> 4) & 0x0f;
788 } else {
789 i = 0;
790 }
791 if (i >= LWIP_6LOWPAN_NUM_CONTEXTS) {
792 /* Error */
793 pbuf_free(p);
794 pbuf_free(q);
795 return NULL;
796 }
797
798 ip6hdr->src.addr[0] = lowpan6_context[i].addr[0];
799 ip6hdr->src.addr[1] = lowpan6_context[i].addr[1];
800 }
801
802 if ((lowpan6_buffer[1] & 0x30) == 0x10) {
803 MEMCPY(&ip6hdr->src.addr[2], lowpan6_buffer + lowpan6_offset, 8);
804 lowpan6_offset += 8;
805 } else if ((lowpan6_buffer[1] & 0x30) == 0x20) {
806 ip6hdr->src.addr[2] = PP_HTONL(0x000000ffUL);
807 ip6hdr->src.addr[3] = lwip_htonl(0xfe000000UL | (lowpan6_buffer[lowpan6_offset] << 8) | lowpan6_buffer[lowpan6_offset+1]);
808 lowpan6_offset += 2;
809 } else if ((lowpan6_buffer[1] & 0x30) == 0x30) {
810 if (src->addr_len == 2) {
811 ip6hdr->src.addr[2] = PP_HTONL(0x000000ffUL);
812 ip6hdr->src.addr[3] = lwip_htonl(0xfe000000UL | (src->addr[0] << 8) | src->addr[1]);
813 } else {
814 ip6hdr->src.addr[2] = lwip_htonl(((src->addr[0] ^ 2) << 24) | (src->addr[1] << 16) | (src->addr[2] << 8) | src->addr[3]);
815 ip6hdr->src.addr[3] = lwip_htonl((src->addr[4] << 24) | (src->addr[5] << 16) | (src->addr[6] << 8) | src->addr[7]);
816 }
817 }
818 }
819
820 /* Destination address decoding. */
821 if (lowpan6_buffer[1] & 0x08) {
822 /* Multicast destination */
823 if (lowpan6_buffer[1] & 0x04) {
824 /* @todo support stateful multicast addressing */
825 pbuf_free(p);
826 pbuf_free(q);
827 return NULL;
828 }
829
830 if ((lowpan6_buffer[1] & 0x03) == 0x00) {
831 /* copy full address */
832 MEMCPY(&ip6hdr->dest.addr[0], lowpan6_buffer + lowpan6_offset, 16);
833 lowpan6_offset += 16;
834 } else if ((lowpan6_buffer[1] & 0x03) == 0x01) {
835 ip6hdr->dest.addr[0] = lwip_htonl(0xff000000UL | (lowpan6_buffer[lowpan6_offset++] << 16));
836 ip6hdr->dest.addr[1] = 0;
837 ip6hdr->dest.addr[2] = lwip_htonl(lowpan6_buffer[lowpan6_offset++]);
838 ip6hdr->dest.addr[3] = lwip_htonl((lowpan6_buffer[lowpan6_offset] << 24) | (lowpan6_buffer[lowpan6_offset + 1] << 16) | (lowpan6_buffer[lowpan6_offset + 2] << 8) | lowpan6_buffer[lowpan6_offset + 3]);
839 lowpan6_offset += 4;
840 } else if ((lowpan6_buffer[1] & 0x03) == 0x02) {
841 ip6hdr->dest.addr[0] = lwip_htonl(0xff000000UL | lowpan6_buffer[lowpan6_offset++]);
842 ip6hdr->dest.addr[1] = 0;
843 ip6hdr->dest.addr[2] = 0;
844 ip6hdr->dest.addr[3] = lwip_htonl((lowpan6_buffer[lowpan6_offset] << 16) | (lowpan6_buffer[lowpan6_offset + 1] << 8) | lowpan6_buffer[lowpan6_offset + 2]);
845 lowpan6_offset += 3;
846 } else if ((lowpan6_buffer[1] & 0x03) == 0x03) {
847 ip6hdr->dest.addr[0] = PP_HTONL(0xff020000UL);
848 ip6hdr->dest.addr[1] = 0;
849 ip6hdr->dest.addr[2] = 0;
850 ip6hdr->dest.addr[3] = lwip_htonl(lowpan6_buffer[lowpan6_offset++]);
851 }
852
853 } else {
854 if (lowpan6_buffer[1] & 0x04) {
855 /* Stateful destination compression */
856 /* Set prefix from context info */
857 if (lowpan6_buffer[1] & 0x80) {
858 i = lowpan6_buffer[2] & 0x0f;
859 } else {
860 i = 0;
861 }
862 if (i >= LWIP_6LOWPAN_NUM_CONTEXTS) {
863 /* Error */
864 pbuf_free(p);
865 pbuf_free(q);
866 return NULL;
867 }
868
869 ip6hdr->dest.addr[0] = lowpan6_context[i].addr[0];
870 ip6hdr->dest.addr[1] = lowpan6_context[i].addr[1];
871 } else {
872 /* Link local address compression */
873 ip6hdr->dest.addr[0] = PP_HTONL(0xfe800000UL);
874 ip6hdr->dest.addr[1] = 0;
875 }
876
877 if ((lowpan6_buffer[1] & 0x03) == 0x00) {
878 /* copy full address */
879 MEMCPY(&ip6hdr->dest.addr[0], lowpan6_buffer + lowpan6_offset, 16);
880 lowpan6_offset += 16;
881 } else if ((lowpan6_buffer[1] & 0x03) == 0x01) {
882 MEMCPY(&ip6hdr->dest.addr[2], lowpan6_buffer + lowpan6_offset, 8);
883 lowpan6_offset += 8;
884 } else if ((lowpan6_buffer[1] & 0x03) == 0x02) {
885 ip6hdr->dest.addr[2] = PP_HTONL(0x000000ffUL);
886 ip6hdr->dest.addr[3] = lwip_htonl(0xfe000000UL | (lowpan6_buffer[lowpan6_offset] << 8) | lowpan6_buffer[lowpan6_offset + 1]);
887 lowpan6_offset += 2;
888 } else if ((lowpan6_buffer[1] & 0x03) == 0x03) {
889 if (dest->addr_len == 2) {
890 ip6hdr->dest.addr[2] = PP_HTONL(0x000000ffUL);
891 ip6hdr->dest.addr[3] = lwip_htonl(0xfe000000UL | (dest->addr[0] << 8) | dest->addr[1]);
892 } else {
893 ip6hdr->dest.addr[2] = lwip_htonl(((dest->addr[0] ^ 2) << 24) | (dest->addr[1] << 16) | dest->addr[2] << 8 | dest->addr[3]);
894 ip6hdr->dest.addr[3] = lwip_htonl((dest->addr[4] << 24) | (dest->addr[5] << 16) | dest->addr[6] << 8 | dest->addr[7]);
895 }
896 }
897 }
898
899
900 /* Next Header Compression (NHC) decoding? */
901 if (lowpan6_buffer[0] & 0x04) {
902 if ((lowpan6_buffer[lowpan6_offset] & 0xf8) == 0xf0) {
903 struct udp_hdr *udphdr;
904
905 /* UDP compression */
906 IP6H_NEXTH_SET(ip6hdr, IP6_NEXTH_UDP);
907 udphdr = (struct udp_hdr *)((u8_t *)q->payload + ip6_offset);
908
909 if (lowpan6_buffer[lowpan6_offset] & 0x04) {
910 /* @todo support checksum decompress */
911 pbuf_free(p);
912 pbuf_free(q);
913 return NULL;
914 }
915
916 /* Decompress ports */
917 i = lowpan6_buffer[lowpan6_offset++] & 0x03;
918 if (i == 0) {
919 udphdr->src = lwip_htons(lowpan6_buffer[lowpan6_offset] << 8 | lowpan6_buffer[lowpan6_offset + 1]);
920 udphdr->dest = lwip_htons(lowpan6_buffer[lowpan6_offset + 2] << 8 | lowpan6_buffer[lowpan6_offset + 3]);
921 lowpan6_offset += 4;
922 } else if (i == 0x01) {
923 udphdr->src = lwip_htons(lowpan6_buffer[lowpan6_offset] << 8 | lowpan6_buffer[lowpan6_offset + 1]);
924 udphdr->dest = lwip_htons(0xf000 | lowpan6_buffer[lowpan6_offset + 2]);
925 lowpan6_offset += 3;
926 } else if (i == 0x02) {
927 udphdr->src = lwip_htons(0xf000 | lowpan6_buffer[lowpan6_offset]);
928 udphdr->dest = lwip_htons(lowpan6_buffer[lowpan6_offset + 1] << 8 | lowpan6_buffer[lowpan6_offset + 2]);
929 lowpan6_offset += 3;
930 } else if (i == 0x03) {
931 udphdr->src = lwip_htons(0xf0b0 | ((lowpan6_buffer[lowpan6_offset] >> 4) & 0x0f));
932 udphdr->dest = lwip_htons(0xf0b0 | (lowpan6_buffer[lowpan6_offset] & 0x0f));
933 lowpan6_offset += 1;
934 }
935
936 udphdr->chksum = lwip_htons(lowpan6_buffer[lowpan6_offset] << 8 | lowpan6_buffer[lowpan6_offset + 1]);
937 lowpan6_offset += 2;
938 udphdr->len = lwip_htons(p->tot_len - lowpan6_offset + UDP_HLEN);
939
940 ip6_offset += UDP_HLEN;
941 } else {
942 /* @todo support NHC other than UDP */
943 pbuf_free(p);
944 pbuf_free(q);
945 return NULL;
946 }
947 }
948
949 /* Now we copy leftover contents from p to q, so we have all L2 and L3 headers (and L4?) in a single PBUF.
950 * Replace p with q, and free p */
951 pbuf_header(p, -lowpan6_offset);
952 MEMCPY((u8_t*)q->payload + ip6_offset, p->payload, p->len);
953 q->len = q->tot_len = ip6_offset + p->len;
954 if (p->next != NULL) {
955 pbuf_cat(q, p->next);
956 }
957 p->next = NULL;
958 pbuf_free(p);
959
960 /* Infer IPv6 payload length for header */
961 IP6H_PLEN_SET(ip6hdr, q->tot_len - IP6_HLEN);
962
963 /* all done */
964 return q;
965 }
966
967 err_t
lowpan6_input(struct pbuf * p,struct netif * netif)968 lowpan6_input(struct pbuf * p, struct netif *netif)
969 {
970 u8_t * puc;
971 s8_t i;
972 struct ieee_802154_addr src, dest;
973 u16_t datagram_size, datagram_offset, datagram_tag;
974 struct lowpan6_reass_helper *lrh, *lrh_temp;
975
976 MIB2_STATS_NETIF_ADD(netif, ifinoctets, p->tot_len);
977
978 /* Analyze header. @todo validate. */
979 puc = (u8_t*)p->payload;
980 datagram_offset = 5;
981 if ((puc[1] & 0x0c) == 0x0c) {
982 dest.addr_len = 8;
983 for (i = 0; i < 8; i++) {
984 dest.addr[i] = puc[datagram_offset + 7 - i];
985 }
986 datagram_offset += 8;
987 } else {
988 dest.addr_len = 2;
989 dest.addr[0] = puc[datagram_offset + 1];
990 dest.addr[1] = puc[datagram_offset];
991 datagram_offset += 2;
992 }
993
994 datagram_offset += 2; /* skip PAN ID. */
995
996 if ((puc[1] & 0xc0) == 0xc0) {
997 src.addr_len = 8;
998 for (i = 0; i < 8; i++) {
999 src.addr[i] = puc[datagram_offset + 7 - i];
1000 }
1001 datagram_offset += 8;
1002 } else {
1003 src.addr_len = 2;
1004 src.addr[0] = puc[datagram_offset + 1];
1005 src.addr[1] = puc[datagram_offset];
1006 datagram_offset += 2;
1007 }
1008
1009 pbuf_header(p, -datagram_offset); /* hide IEEE802.15.4 header. */
1010
1011 /* Check dispatch. */
1012 puc = (u8_t*)p->payload;
1013
1014 if ((*puc & 0xf8) == 0xc0) {
1015 /* FRAG1 dispatch. add this packet to reassembly list. */
1016 datagram_size = ((u16_t)(puc[0] & 0x07) << 8) | (u16_t)puc[1];
1017 datagram_tag = ((u16_t)puc[2] << 8) | (u16_t)puc[3];
1018
1019 /* check for duplicate */
1020 lrh = reass_list;
1021 while (lrh != NULL) {
1022 if ((lrh->sender_addr.addr_len == src.addr_len) &&
1023 (memcmp(lrh->sender_addr.addr, src.addr, src.addr_len) == 0)) {
1024 /* address match with packet in reassembly. */
1025 if ((datagram_tag == lrh->datagram_tag) && (datagram_size == lrh->datagram_size)) {
1026 MIB2_STATS_NETIF_INC(netif, ifindiscards);
1027 /* duplicate fragment. */
1028 pbuf_free(p);
1029 return ERR_OK;
1030 } else {
1031 /* We are receiving the start of a new datagram. Discard old one (incomplete). */
1032 lrh_temp = lrh->next_packet;
1033 dequeue_datagram(lrh);
1034 pbuf_free(lrh->pbuf);
1035 mem_free(lrh);
1036
1037 /* Check next datagram in queue. */
1038 lrh = lrh_temp;
1039 }
1040 } else {
1041 /* Check next datagram in queue. */
1042 lrh = lrh->next_packet;
1043 }
1044 }
1045
1046 pbuf_header(p, -4); /* hide frag1 dispatch */
1047
1048 lrh = (struct lowpan6_reass_helper *) mem_malloc(sizeof(struct lowpan6_reass_helper));
1049 if (lrh == NULL) {
1050 MIB2_STATS_NETIF_INC(netif, ifindiscards);
1051 pbuf_free(p);
1052 return ERR_MEM;
1053 }
1054
1055 lrh->sender_addr.addr_len = src.addr_len;
1056 for (i = 0; i < src.addr_len; i++) {
1057 lrh->sender_addr.addr[i] = src.addr[i];
1058 }
1059 lrh->datagram_size = datagram_size;
1060 lrh->datagram_tag = datagram_tag;
1061 lrh->pbuf = p;
1062 lrh->next_packet = reass_list;
1063 lrh->timer = 2;
1064 reass_list = lrh;
1065
1066 return ERR_OK;
1067 } else if ((*puc & 0xf8) == 0xe0) {
1068 /* FRAGN dispatch, find packet being reassembled. */
1069 datagram_size = ((u16_t)(puc[0] & 0x07) << 8) | (u16_t)puc[1];
1070 datagram_tag = ((u16_t)puc[2] << 8) | (u16_t)puc[3];
1071 datagram_offset = (u16_t)puc[4] << 3;
1072 pbuf_header(p, -5); /* hide frag1 dispatch */
1073
1074 for (lrh = reass_list; lrh != NULL; lrh = lrh->next_packet) {
1075 if ((lrh->sender_addr.addr_len == src.addr_len) &&
1076 (memcmp(lrh->sender_addr.addr, src.addr, src.addr_len) == 0) &&
1077 (datagram_tag == lrh->datagram_tag) &&
1078 (datagram_size == lrh->datagram_size)) {
1079 break;
1080 }
1081 }
1082 if (lrh == NULL) {
1083 /* rogue fragment */
1084 MIB2_STATS_NETIF_INC(netif, ifindiscards);
1085 pbuf_free(p);
1086 return ERR_OK;
1087 }
1088
1089 if (lrh->pbuf->tot_len < datagram_offset) {
1090 /* duplicate, ignore. */
1091 pbuf_free(p);
1092 return ERR_OK;
1093 } else if (lrh->pbuf->tot_len > datagram_offset) {
1094 MIB2_STATS_NETIF_INC(netif, ifindiscards);
1095 /* We have missed a fragment. Delete whole reassembly. */
1096 dequeue_datagram(lrh);
1097 pbuf_free(lrh->pbuf);
1098 mem_free(lrh);
1099 pbuf_free(p);
1100 return ERR_OK;
1101 }
1102 pbuf_cat(lrh->pbuf, p);
1103 p = NULL;
1104
1105 /* is packet now complete?*/
1106 if (lrh->pbuf->tot_len >= lrh->datagram_size) {
1107 /* dequeue from reass list. */
1108 dequeue_datagram(lrh);
1109
1110 /* get pbuf */
1111 p = lrh->pbuf;
1112
1113 /* release helper */
1114 mem_free(lrh);
1115 } else {
1116 return ERR_OK;
1117 }
1118 }
1119
1120 if (p == NULL) {
1121 return ERR_OK;
1122 }
1123
1124 /* We have a complete packet, check dispatch for headers. */
1125 puc = (u8_t*)p->payload;
1126
1127 if (*puc == 0x41) {
1128 /* This is a complete IPv6 packet, just skip dispatch byte. */
1129 pbuf_header(p, -1); /* hide dispatch byte. */
1130 } else if ((*puc & 0xe0 )== 0x60) {
1131 /* IPv6 headers are compressed using IPHC. */
1132 p = lowpan6_decompress(p, &src, &dest);
1133 if (p == NULL) {
1134 MIB2_STATS_NETIF_INC(netif, ifindiscards);
1135 return ERR_OK;
1136 }
1137 } else {
1138 MIB2_STATS_NETIF_INC(netif, ifindiscards);
1139 pbuf_free(p);
1140 return ERR_OK;
1141 }
1142
1143 /* @todo: distinguish unicast/multicast */
1144 MIB2_STATS_NETIF_INC(netif, ifinucastpkts);
1145
1146 return ip6_input(p, netif);
1147 }
1148
1149 err_t
lowpan6_if_init(struct netif * netif)1150 lowpan6_if_init(struct netif *netif)
1151 {
1152 netif->name[0] = 'L';
1153 netif->name[1] = '6';
1154 #if LWIP_IPV4
1155 netif->output = lowpan4_output;
1156 #endif /* LWIP_IPV4 */
1157 netif->output_ip6 = lowpan6_output;
1158
1159 MIB2_INIT_NETIF(netif, snmp_ifType_other, 0);
1160
1161 /* maximum transfer unit */
1162 netif->mtu = 1280;
1163
1164 /* broadcast capability */
1165 netif->flags = NETIF_FLAG_BROADCAST /* | NETIF_FLAG_LOWPAN6 */;
1166
1167 return ERR_OK;
1168 }
1169
1170 err_t
lowpan6_set_pan_id(u16_t pan_id)1171 lowpan6_set_pan_id(u16_t pan_id)
1172 {
1173 ieee_802154_pan_id = pan_id;
1174
1175 return ERR_OK;
1176 }
1177
1178 #if !NO_SYS
1179 /**
1180 * Pass a received packet to tcpip_thread for input processing
1181 *
1182 * @param p the received packet, p->payload pointing to the
1183 * IEEE 802.15.4 header.
1184 * @param inp the network interface on which the packet was received
1185 */
1186 err_t
tcpip_6lowpan_input(struct pbuf * p,struct netif * inp)1187 tcpip_6lowpan_input(struct pbuf *p, struct netif *inp)
1188 {
1189 return tcpip_inpkt(p, inp, lowpan6_input);
1190 }
1191 #endif /* !NO_SYS */
1192
1193 #endif /* LWIP_IPV6 && LWIP_6LOWPAN */
1194