[457] | 1 | /**
|
---|
| 2 | * @file
|
---|
| 3 | *
|
---|
| 4 | * 6LowPAN output for IPv6. Uses ND tables for link-layer addressing. Fragments packets to 6LowPAN units.
|
---|
| 5 | *
|
---|
| 6 | * This implementation aims to conform to IEEE 802.15.4(-2015), RFC 4944 and RFC 6282.
|
---|
| 7 | * @todo: RFC 6775.
|
---|
| 8 | */
|
---|
| 9 |
|
---|
| 10 | /*
|
---|
| 11 | * Copyright (c) 2015 Inico Technologies Ltd.
|
---|
| 12 | * All rights reserved.
|
---|
| 13 | *
|
---|
| 14 | * Redistribution and use in source and binary forms, with or without modification,
|
---|
| 15 | * are permitted provided that the following conditions are met:
|
---|
| 16 | *
|
---|
| 17 | * 1. Redistributions of source code must retain the above copyright notice,
|
---|
| 18 | * this list of conditions and the following disclaimer.
|
---|
| 19 | * 2. Redistributions in binary form must reproduce the above copyright notice,
|
---|
| 20 | * this list of conditions and the following disclaimer in the documentation
|
---|
| 21 | * and/or other materials provided with the distribution.
|
---|
| 22 | * 3. The name of the author may not be used to endorse or promote products
|
---|
| 23 | * derived from this software without specific prior written permission.
|
---|
| 24 | *
|
---|
| 25 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
|
---|
| 26 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
|
---|
| 27 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
|
---|
| 28 | * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
---|
| 29 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
|
---|
| 30 | * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
---|
| 31 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
---|
| 32 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
|
---|
| 33 | * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
|
---|
| 34 | * OF SUCH DAMAGE.
|
---|
| 35 | *
|
---|
| 36 | * This file is part of the lwIP TCP/IP stack.
|
---|
| 37 | *
|
---|
| 38 | * Author: Ivan Delamer <delamer@inicotech.com>
|
---|
| 39 | *
|
---|
| 40 | *
|
---|
| 41 | * Please coordinate changes and requests with Ivan Delamer
|
---|
| 42 | * <delamer@inicotech.com>
|
---|
| 43 | */
|
---|
| 44 |
|
---|
| 45 | /**
|
---|
| 46 | * @defgroup sixlowpan 6LoWPAN (RFC4944)
|
---|
| 47 | * @ingroup netifs
|
---|
| 48 | * 6LowPAN netif implementation
|
---|
| 49 | */
|
---|
| 50 |
|
---|
| 51 | #include "netif/lowpan6.h"
|
---|
| 52 |
|
---|
| 53 | #if LWIP_IPV6
|
---|
| 54 |
|
---|
| 55 | #include "lwip/ip.h"
|
---|
| 56 | #include "lwip/pbuf.h"
|
---|
| 57 | #include "lwip/ip_addr.h"
|
---|
| 58 | #include "lwip/netif.h"
|
---|
| 59 | #include "lwip/nd6.h"
|
---|
| 60 | #include "lwip/mem.h"
|
---|
| 61 | #include "lwip/udp.h"
|
---|
| 62 | #include "lwip/tcpip.h"
|
---|
| 63 | #include "lwip/snmp.h"
|
---|
| 64 | #include "netif/ieee802154.h"
|
---|
| 65 |
|
---|
| 66 | #include <string.h>
|
---|
| 67 |
|
---|
| 68 | #if LWIP_6LOWPAN_802154_HW_CRC
|
---|
| 69 | #define LWIP_6LOWPAN_DO_CALC_CRC(buf, len) 0
|
---|
| 70 | #else
|
---|
| 71 | #define LWIP_6LOWPAN_DO_CALC_CRC(buf, len) LWIP_6LOWPAN_CALC_CRC(buf, len)
|
---|
| 72 | #endif
|
---|
| 73 |
|
---|
| 74 | /** This is a helper struct for reassembly of fragments
|
---|
| 75 | * (IEEE 802.15.4 limits to 127 bytes)
|
---|
| 76 | */
|
---|
| 77 | struct lowpan6_reass_helper {
|
---|
| 78 | struct lowpan6_reass_helper *next_packet;
|
---|
| 79 | struct pbuf *reass;
|
---|
| 80 | struct pbuf *frags;
|
---|
| 81 | u8_t timer;
|
---|
| 82 | struct lowpan6_link_addr sender_addr;
|
---|
| 83 | u16_t datagram_size;
|
---|
| 84 | u16_t datagram_tag;
|
---|
| 85 | };
|
---|
| 86 |
|
---|
| 87 | /** This struct keeps track of per-netif state */
|
---|
| 88 | struct lowpan6_ieee802154_data {
|
---|
| 89 | /** fragment reassembly list */
|
---|
| 90 | struct lowpan6_reass_helper *reass_list;
|
---|
| 91 | #if LWIP_6LOWPAN_NUM_CONTEXTS > 0
|
---|
| 92 | /** address context for compression */
|
---|
| 93 | ip6_addr_t lowpan6_context[LWIP_6LOWPAN_NUM_CONTEXTS];
|
---|
| 94 | #endif
|
---|
| 95 | /** Datagram Tag for fragmentation */
|
---|
| 96 | u16_t tx_datagram_tag;
|
---|
| 97 | /** local PAN ID for IEEE 802.15.4 header */
|
---|
| 98 | u16_t ieee_802154_pan_id;
|
---|
| 99 | /** Sequence Number for IEEE 802.15.4 transmission */
|
---|
| 100 | u8_t tx_frame_seq_num;
|
---|
| 101 | };
|
---|
| 102 |
|
---|
| 103 | /* Maximum frame size is 127 bytes minus CRC size */
|
---|
| 104 | #define LOWPAN6_MAX_PAYLOAD (127 - 2)
|
---|
| 105 |
|
---|
| 106 | /** Currently, this state is global, since there's only one 6LoWPAN netif */
|
---|
| 107 | static struct lowpan6_ieee802154_data lowpan6_data;
|
---|
| 108 |
|
---|
| 109 | #if LWIP_6LOWPAN_NUM_CONTEXTS > 0
|
---|
| 110 | #define LWIP_6LOWPAN_CONTEXTS(netif) lowpan6_data.lowpan6_context
|
---|
| 111 | #else
|
---|
| 112 | #define LWIP_6LOWPAN_CONTEXTS(netif) NULL
|
---|
| 113 | #endif
|
---|
| 114 |
|
---|
| 115 | static const struct lowpan6_link_addr ieee_802154_broadcast = {2, {0xff, 0xff}};
|
---|
| 116 |
|
---|
| 117 | #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
|
---|
| 118 | static struct lowpan6_link_addr short_mac_addr = {2, {0, 0}};
|
---|
| 119 | #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
|
---|
| 120 |
|
---|
| 121 | /* IEEE 802.15.4 specific functions: */
|
---|
| 122 |
|
---|
| 123 | /** Write the IEEE 802.15.4 header that encapsulates the 6LoWPAN frame.
|
---|
| 124 | * Src and dst PAN IDs are filled with the ID set by @ref lowpan6_set_pan_id.
|
---|
| 125 | *
|
---|
| 126 | * Since the length is variable:
|
---|
| 127 | * @returns the header length
|
---|
| 128 | */
|
---|
| 129 | static u8_t
|
---|
| 130 | lowpan6_write_iee802154_header(struct ieee_802154_hdr *hdr, const struct lowpan6_link_addr *src,
|
---|
| 131 | const struct lowpan6_link_addr *dst)
|
---|
| 132 | {
|
---|
| 133 | u8_t ieee_header_len;
|
---|
| 134 | u8_t *buffer;
|
---|
| 135 | u8_t i;
|
---|
| 136 | u16_t fc;
|
---|
| 137 |
|
---|
| 138 | fc = IEEE_802154_FC_FT_DATA; /* send data packet (2003 frame version) */
|
---|
| 139 | fc |= IEEE_802154_FC_PANID_COMPR; /* set PAN ID compression, for now src and dst PANs are equal */
|
---|
| 140 | if (dst != &ieee_802154_broadcast) {
|
---|
| 141 | fc |= IEEE_802154_FC_ACK_REQ; /* data packet, no broadcast: ack required. */
|
---|
| 142 | }
|
---|
| 143 | if (dst->addr_len == 2) {
|
---|
| 144 | fc |= IEEE_802154_FC_DST_ADDR_MODE_SHORT;
|
---|
| 145 | } else {
|
---|
| 146 | LWIP_ASSERT("invalid dst address length", dst->addr_len == 8);
|
---|
| 147 | fc |= IEEE_802154_FC_DST_ADDR_MODE_EXT;
|
---|
| 148 | }
|
---|
| 149 | if (src->addr_len == 2) {
|
---|
| 150 | fc |= IEEE_802154_FC_SRC_ADDR_MODE_SHORT;
|
---|
| 151 | } else {
|
---|
| 152 | LWIP_ASSERT("invalid src address length", src->addr_len == 8);
|
---|
| 153 | fc |= IEEE_802154_FC_SRC_ADDR_MODE_EXT;
|
---|
| 154 | }
|
---|
| 155 | hdr->frame_control = fc;
|
---|
| 156 | hdr->sequence_number = lowpan6_data.tx_frame_seq_num++;
|
---|
| 157 | hdr->destination_pan_id = lowpan6_data.ieee_802154_pan_id; /* pan id */
|
---|
| 158 |
|
---|
| 159 | buffer = (u8_t *)hdr;
|
---|
| 160 | ieee_header_len = 5;
|
---|
| 161 | i = dst->addr_len;
|
---|
| 162 | /* reverse memcpy of dst addr */
|
---|
| 163 | while (i-- > 0) {
|
---|
| 164 | buffer[ieee_header_len++] = dst->addr[i];
|
---|
| 165 | }
|
---|
| 166 | /* Source PAN ID skipped due to PAN ID Compression */
|
---|
| 167 | i = src->addr_len;
|
---|
| 168 | /* reverse memcpy of src addr */
|
---|
| 169 | while (i-- > 0) {
|
---|
| 170 | buffer[ieee_header_len++] = src->addr[i];
|
---|
| 171 | }
|
---|
| 172 | return ieee_header_len;
|
---|
| 173 | }
|
---|
| 174 |
|
---|
| 175 | /** Parse the IEEE 802.15.4 header from a pbuf.
|
---|
| 176 | * If successful, the header is hidden from the pbuf.
|
---|
| 177 | *
|
---|
| 178 | * PAN IDs and seuqence number are not checked
|
---|
| 179 | *
|
---|
| 180 | * @param p input pbuf, p->payload pointing at the IEEE 802.15.4 header
|
---|
| 181 | * @param src pointer to source address filled from the header
|
---|
| 182 | * @param dest pointer to destination address filled from the header
|
---|
| 183 | * @returns ERR_OK if successful
|
---|
| 184 | */
|
---|
| 185 | static err_t
|
---|
| 186 | lowpan6_parse_iee802154_header(struct pbuf *p, struct lowpan6_link_addr *src,
|
---|
| 187 | struct lowpan6_link_addr *dest)
|
---|
| 188 | {
|
---|
| 189 | u8_t *puc;
|
---|
| 190 | s8_t i;
|
---|
| 191 | u16_t frame_control, addr_mode;
|
---|
| 192 | u16_t datagram_offset;
|
---|
| 193 |
|
---|
| 194 | /* Parse IEEE 802.15.4 header */
|
---|
| 195 | puc = (u8_t *)p->payload;
|
---|
| 196 | frame_control = puc[0] | (puc[1] << 8);
|
---|
| 197 | datagram_offset = 2;
|
---|
| 198 | if (frame_control & IEEE_802154_FC_SEQNO_SUPPR) {
|
---|
| 199 | if (IEEE_802154_FC_FRAME_VERSION_GET(frame_control) <= 1) {
|
---|
| 200 | /* sequence number suppressed, this is not valid for versions 0/1 */
|
---|
| 201 | return ERR_VAL;
|
---|
| 202 | }
|
---|
| 203 | } else {
|
---|
| 204 | datagram_offset++;
|
---|
| 205 | }
|
---|
| 206 | datagram_offset += 2; /* Skip destination PAN ID */
|
---|
| 207 | addr_mode = frame_control & IEEE_802154_FC_DST_ADDR_MODE_MASK;
|
---|
| 208 | if (addr_mode == IEEE_802154_FC_DST_ADDR_MODE_EXT) {
|
---|
| 209 | /* extended address (64 bit) */
|
---|
| 210 | dest->addr_len = 8;
|
---|
| 211 | /* reverse memcpy: */
|
---|
| 212 | for (i = 0; i < 8; i++) {
|
---|
| 213 | dest->addr[i] = puc[datagram_offset + 7 - i];
|
---|
| 214 | }
|
---|
| 215 | datagram_offset += 8;
|
---|
| 216 | } else if (addr_mode == IEEE_802154_FC_DST_ADDR_MODE_SHORT) {
|
---|
| 217 | /* short address (16 bit) */
|
---|
| 218 | dest->addr_len = 2;
|
---|
| 219 | /* reverse memcpy: */
|
---|
| 220 | dest->addr[0] = puc[datagram_offset + 1];
|
---|
| 221 | dest->addr[1] = puc[datagram_offset];
|
---|
| 222 | datagram_offset += 2;
|
---|
| 223 | } else {
|
---|
| 224 | /* unsupported address mode (do we need "no address"?) */
|
---|
| 225 | return ERR_VAL;
|
---|
| 226 | }
|
---|
| 227 |
|
---|
| 228 | if (!(frame_control & IEEE_802154_FC_PANID_COMPR)) {
|
---|
| 229 | /* No PAN ID compression, skip source PAN ID */
|
---|
| 230 | datagram_offset += 2;
|
---|
| 231 | }
|
---|
| 232 |
|
---|
| 233 | addr_mode = frame_control & IEEE_802154_FC_SRC_ADDR_MODE_MASK;
|
---|
| 234 | if (addr_mode == IEEE_802154_FC_SRC_ADDR_MODE_EXT) {
|
---|
| 235 | /* extended address (64 bit) */
|
---|
| 236 | src->addr_len = 8;
|
---|
| 237 | /* reverse memcpy: */
|
---|
| 238 | for (i = 0; i < 8; i++) {
|
---|
| 239 | src->addr[i] = puc[datagram_offset + 7 - i];
|
---|
| 240 | }
|
---|
| 241 | datagram_offset += 8;
|
---|
| 242 | } else if (addr_mode == IEEE_802154_FC_DST_ADDR_MODE_SHORT) {
|
---|
| 243 | /* short address (16 bit) */
|
---|
| 244 | src->addr_len = 2;
|
---|
| 245 | src->addr[0] = puc[datagram_offset + 1];
|
---|
| 246 | src->addr[1] = puc[datagram_offset];
|
---|
| 247 | datagram_offset += 2;
|
---|
| 248 | } else {
|
---|
| 249 | /* unsupported address mode (do we need "no address"?) */
|
---|
| 250 | return ERR_VAL;
|
---|
| 251 | }
|
---|
| 252 |
|
---|
| 253 | /* hide IEEE802.15.4 header. */
|
---|
| 254 | if (pbuf_remove_header(p, datagram_offset)) {
|
---|
| 255 | return ERR_VAL;
|
---|
| 256 | }
|
---|
| 257 | return ERR_OK;
|
---|
| 258 | }
|
---|
| 259 |
|
---|
| 260 | /** Calculate the 16-bit CRC as required by IEEE 802.15.4 */
|
---|
| 261 | u16_t
|
---|
| 262 | lowpan6_calc_crc(const void* buf, u16_t len)
|
---|
| 263 | {
|
---|
| 264 | #define CCITT_POLY_16 0x8408U
|
---|
| 265 | u16_t i;
|
---|
| 266 | u8_t b;
|
---|
| 267 | u16_t crc = 0;
|
---|
| 268 | const u8_t* p = (const u8_t*)buf;
|
---|
| 269 |
|
---|
| 270 | for (i = 0; i < len; i++) {
|
---|
| 271 | u8_t data = *p;
|
---|
| 272 | for (b = 0U; b < 8U; b++) {
|
---|
| 273 | if (((data ^ crc) & 1) != 0) {
|
---|
| 274 | crc = (u16_t)((crc >> 1) ^ CCITT_POLY_16);
|
---|
| 275 | } else {
|
---|
| 276 | crc = (u16_t)(crc >> 1);
|
---|
| 277 | }
|
---|
| 278 | data = (u8_t)(data >> 1);
|
---|
| 279 | }
|
---|
| 280 | p++;
|
---|
| 281 | }
|
---|
| 282 | return crc;
|
---|
| 283 | }
|
---|
| 284 |
|
---|
| 285 | /* Fragmentation specific functions: */
|
---|
| 286 |
|
---|
| 287 | static void
|
---|
| 288 | free_reass_datagram(struct lowpan6_reass_helper *lrh)
|
---|
| 289 | {
|
---|
| 290 | if (lrh->reass) {
|
---|
| 291 | pbuf_free(lrh->reass);
|
---|
| 292 | }
|
---|
| 293 | if (lrh->frags) {
|
---|
| 294 | pbuf_free(lrh->frags);
|
---|
| 295 | }
|
---|
| 296 | mem_free(lrh);
|
---|
| 297 | }
|
---|
| 298 |
|
---|
| 299 | /**
|
---|
| 300 | * Removes a datagram from the reassembly queue.
|
---|
| 301 | **/
|
---|
| 302 | static void
|
---|
| 303 | dequeue_datagram(struct lowpan6_reass_helper *lrh, struct lowpan6_reass_helper *prev)
|
---|
| 304 | {
|
---|
| 305 | if (lowpan6_data.reass_list == lrh) {
|
---|
| 306 | lowpan6_data.reass_list = lowpan6_data.reass_list->next_packet;
|
---|
| 307 | } else {
|
---|
| 308 | /* it wasn't the first, so it must have a valid 'prev' */
|
---|
| 309 | LWIP_ASSERT("sanity check linked list", prev != NULL);
|
---|
| 310 | prev->next_packet = lrh->next_packet;
|
---|
| 311 | }
|
---|
| 312 | }
|
---|
| 313 |
|
---|
| 314 | /**
|
---|
| 315 | * Periodic timer for 6LowPAN functions:
|
---|
| 316 | *
|
---|
| 317 | * - Remove incomplete/old packets
|
---|
| 318 | */
|
---|
| 319 | void
|
---|
| 320 | lowpan6_tmr(void)
|
---|
| 321 | {
|
---|
| 322 | struct lowpan6_reass_helper *lrh, *lrh_next, *lrh_prev = NULL;
|
---|
| 323 |
|
---|
| 324 | lrh = lowpan6_data.reass_list;
|
---|
| 325 | while (lrh != NULL) {
|
---|
| 326 | lrh_next = lrh->next_packet;
|
---|
| 327 | if ((--lrh->timer) == 0) {
|
---|
| 328 | dequeue_datagram(lrh, lrh_prev);
|
---|
| 329 | free_reass_datagram(lrh);
|
---|
| 330 | } else {
|
---|
| 331 | lrh_prev = lrh;
|
---|
| 332 | }
|
---|
| 333 | lrh = lrh_next;
|
---|
| 334 | }
|
---|
| 335 | }
|
---|
| 336 |
|
---|
| 337 | /*
|
---|
| 338 | * Encapsulates data into IEEE 802.15.4 frames.
|
---|
| 339 | * Fragments an IPv6 datagram into 6LowPAN units, which fit into IEEE 802.15.4 frames.
|
---|
| 340 | * If configured, will compress IPv6 and or UDP headers.
|
---|
| 341 | * */
|
---|
| 342 | static err_t
|
---|
| 343 | lowpan6_frag(struct netif *netif, struct pbuf *p, const struct lowpan6_link_addr *src, const struct lowpan6_link_addr *dst)
|
---|
| 344 | {
|
---|
| 345 | struct pbuf *p_frag;
|
---|
| 346 | u16_t frag_len, remaining_len, max_data_len;
|
---|
| 347 | u8_t *buffer;
|
---|
| 348 | u8_t ieee_header_len;
|
---|
| 349 | u8_t lowpan6_header_len;
|
---|
| 350 | u8_t hidden_header_len;
|
---|
| 351 | u16_t crc;
|
---|
| 352 | u16_t datagram_offset;
|
---|
| 353 | err_t err = ERR_IF;
|
---|
| 354 |
|
---|
| 355 | LWIP_ASSERT("lowpan6_frag: netif->linkoutput not set", netif->linkoutput != NULL);
|
---|
| 356 |
|
---|
| 357 | /* We'll use a dedicated pbuf for building 6LowPAN fragments. */
|
---|
| 358 | p_frag = pbuf_alloc(PBUF_RAW, 127, PBUF_RAM);
|
---|
| 359 | if (p_frag == NULL) {
|
---|
| 360 | MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
|
---|
| 361 | return ERR_MEM;
|
---|
| 362 | }
|
---|
| 363 | LWIP_ASSERT("this needs a pbuf in one piece", p_frag->len == p_frag->tot_len);
|
---|
| 364 |
|
---|
| 365 | /* Write IEEE 802.15.4 header. */
|
---|
| 366 | buffer = (u8_t *)p_frag->payload;
|
---|
| 367 | ieee_header_len = lowpan6_write_iee802154_header((struct ieee_802154_hdr *)buffer, src, dst);
|
---|
| 368 | LWIP_ASSERT("ieee_header_len < p_frag->len", ieee_header_len < p_frag->len);
|
---|
| 369 |
|
---|
| 370 | #if LWIP_6LOWPAN_IPHC
|
---|
| 371 | /* Perform 6LowPAN IPv6 header compression according to RFC 6282 */
|
---|
| 372 | /* do the header compression (this does NOT copy any non-compressed data) */
|
---|
| 373 | err = lowpan6_compress_headers(netif, (u8_t *)p->payload, p->len,
|
---|
| 374 | &buffer[ieee_header_len], p_frag->len - ieee_header_len, &lowpan6_header_len,
|
---|
| 375 | &hidden_header_len, LWIP_6LOWPAN_CONTEXTS(netif), src, dst);
|
---|
| 376 | if (err != ERR_OK) {
|
---|
| 377 | MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
|
---|
| 378 | pbuf_free(p_frag);
|
---|
| 379 | return err;
|
---|
| 380 | }
|
---|
| 381 | pbuf_remove_header(p, hidden_header_len);
|
---|
| 382 |
|
---|
| 383 | #else /* LWIP_6LOWPAN_IPHC */
|
---|
| 384 | /* Send uncompressed IPv6 header with appropriate dispatch byte. */
|
---|
| 385 | lowpan6_header_len = 1;
|
---|
| 386 | buffer[ieee_header_len] = 0x41; /* IPv6 dispatch */
|
---|
| 387 | #endif /* LWIP_6LOWPAN_IPHC */
|
---|
| 388 |
|
---|
| 389 | /* Calculate remaining packet length */
|
---|
| 390 | remaining_len = p->tot_len;
|
---|
| 391 |
|
---|
| 392 | if (remaining_len > 0x7FF) {
|
---|
| 393 | MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
|
---|
| 394 | /* datagram_size must fit into 11 bit */
|
---|
| 395 | pbuf_free(p_frag);
|
---|
| 396 | return ERR_VAL;
|
---|
| 397 | }
|
---|
| 398 |
|
---|
| 399 | /* Fragment, or 1 packet? */
|
---|
| 400 | max_data_len = LOWPAN6_MAX_PAYLOAD - ieee_header_len - lowpan6_header_len;
|
---|
| 401 | if (remaining_len > max_data_len) {
|
---|
| 402 | u16_t data_len;
|
---|
| 403 | /* We must move the 6LowPAN header to make room for the FRAG header. */
|
---|
| 404 | memmove(&buffer[ieee_header_len + 4], &buffer[ieee_header_len], lowpan6_header_len);
|
---|
| 405 |
|
---|
| 406 | /* Now we need to fragment the packet. FRAG1 header first */
|
---|
| 407 | buffer[ieee_header_len] = 0xc0 | (((p->tot_len + hidden_header_len) >> 8) & 0x7);
|
---|
| 408 | buffer[ieee_header_len + 1] = (p->tot_len + hidden_header_len) & 0xff;
|
---|
| 409 |
|
---|
| 410 | lowpan6_data.tx_datagram_tag++;
|
---|
| 411 | buffer[ieee_header_len + 2] = (lowpan6_data.tx_datagram_tag >> 8) & 0xff;
|
---|
| 412 | buffer[ieee_header_len + 3] = lowpan6_data.tx_datagram_tag & 0xff;
|
---|
| 413 |
|
---|
| 414 | /* Fragment follows. */
|
---|
| 415 | data_len = (max_data_len - 4) & 0xf8;
|
---|
| 416 | frag_len = data_len + lowpan6_header_len;
|
---|
| 417 |
|
---|
| 418 | pbuf_copy_partial(p, buffer + ieee_header_len + lowpan6_header_len + 4, frag_len - lowpan6_header_len, 0);
|
---|
| 419 | remaining_len -= frag_len - lowpan6_header_len;
|
---|
| 420 | /* datagram offset holds the offset before compression */
|
---|
| 421 | datagram_offset = frag_len - lowpan6_header_len + hidden_header_len;
|
---|
| 422 | LWIP_ASSERT("datagram offset must be a multiple of 8", (datagram_offset & 7) == 0);
|
---|
| 423 |
|
---|
| 424 | /* Calculate frame length */
|
---|
| 425 | p_frag->len = p_frag->tot_len = ieee_header_len + 4 + frag_len + 2; /* add 2 bytes for crc*/
|
---|
| 426 |
|
---|
| 427 | /* 2 bytes CRC */
|
---|
| 428 | crc = LWIP_6LOWPAN_DO_CALC_CRC(p_frag->payload, p_frag->len - 2);
|
---|
| 429 | pbuf_take_at(p_frag, &crc, 2, p_frag->len - 2);
|
---|
| 430 |
|
---|
| 431 | /* send the packet */
|
---|
| 432 | MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p_frag->tot_len);
|
---|
| 433 | LWIP_DEBUGF(LWIP_LOWPAN6_DEBUG | LWIP_DBG_TRACE, ("lowpan6_send: sending packet %p\n", (void *)p));
|
---|
| 434 | err = netif->linkoutput(netif, p_frag);
|
---|
| 435 |
|
---|
| 436 | while ((remaining_len > 0) && (err == ERR_OK)) {
|
---|
| 437 | struct ieee_802154_hdr *hdr = (struct ieee_802154_hdr *)buffer;
|
---|
| 438 | /* new frame, new seq num for ACK */
|
---|
| 439 | hdr->sequence_number = lowpan6_data.tx_frame_seq_num++;
|
---|
| 440 |
|
---|
| 441 | buffer[ieee_header_len] |= 0x20; /* Change FRAG1 to FRAGN */
|
---|
| 442 |
|
---|
| 443 | LWIP_ASSERT("datagram offset must be a multiple of 8", (datagram_offset & 7) == 0);
|
---|
| 444 | buffer[ieee_header_len + 4] = (u8_t)(datagram_offset >> 3); /* datagram offset in FRAGN header (datagram_offset is max. 11 bit) */
|
---|
| 445 |
|
---|
| 446 | frag_len = (127 - ieee_header_len - 5 - 2) & 0xf8;
|
---|
| 447 | if (frag_len > remaining_len) {
|
---|
| 448 | frag_len = remaining_len;
|
---|
| 449 | }
|
---|
| 450 |
|
---|
| 451 | pbuf_copy_partial(p, buffer + ieee_header_len + 5, frag_len, p->tot_len - remaining_len);
|
---|
| 452 | remaining_len -= frag_len;
|
---|
| 453 | datagram_offset += frag_len;
|
---|
| 454 |
|
---|
| 455 | /* Calculate frame length */
|
---|
| 456 | p_frag->len = p_frag->tot_len = frag_len + 5 + ieee_header_len + 2;
|
---|
| 457 |
|
---|
| 458 | /* 2 bytes CRC */
|
---|
| 459 | crc = LWIP_6LOWPAN_DO_CALC_CRC(p_frag->payload, p_frag->len - 2);
|
---|
| 460 | pbuf_take_at(p_frag, &crc, 2, p_frag->len - 2);
|
---|
| 461 |
|
---|
| 462 | /* send the packet */
|
---|
| 463 | MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p_frag->tot_len);
|
---|
| 464 | LWIP_DEBUGF(LWIP_LOWPAN6_DEBUG | LWIP_DBG_TRACE, ("lowpan6_send: sending packet %p\n", (void *)p));
|
---|
| 465 | err = netif->linkoutput(netif, p_frag);
|
---|
| 466 | }
|
---|
| 467 | } else {
|
---|
| 468 | /* It fits in one frame. */
|
---|
| 469 | frag_len = remaining_len;
|
---|
| 470 |
|
---|
| 471 | /* Copy IPv6 packet */
|
---|
| 472 | pbuf_copy_partial(p, buffer + ieee_header_len + lowpan6_header_len, frag_len, 0);
|
---|
| 473 | remaining_len = 0;
|
---|
| 474 |
|
---|
| 475 | /* Calculate frame length */
|
---|
| 476 | p_frag->len = p_frag->tot_len = frag_len + lowpan6_header_len + ieee_header_len + 2;
|
---|
| 477 | LWIP_ASSERT("", p_frag->len <= 127);
|
---|
| 478 |
|
---|
| 479 | /* 2 bytes CRC */
|
---|
| 480 | crc = LWIP_6LOWPAN_DO_CALC_CRC(p_frag->payload, p_frag->len - 2);
|
---|
| 481 | pbuf_take_at(p_frag, &crc, 2, p_frag->len - 2);
|
---|
| 482 |
|
---|
| 483 | /* send the packet */
|
---|
| 484 | MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p_frag->tot_len);
|
---|
| 485 | LWIP_DEBUGF(LWIP_LOWPAN6_DEBUG | LWIP_DBG_TRACE, ("lowpan6_send: sending packet %p\n", (void *)p));
|
---|
| 486 | err = netif->linkoutput(netif, p_frag);
|
---|
| 487 | }
|
---|
| 488 |
|
---|
| 489 | pbuf_free(p_frag);
|
---|
| 490 |
|
---|
| 491 | return err;
|
---|
| 492 | }
|
---|
| 493 |
|
---|
| 494 | /**
|
---|
| 495 | * @ingroup sixlowpan
|
---|
| 496 | * Set context
|
---|
| 497 | */
|
---|
| 498 | err_t
|
---|
| 499 | lowpan6_set_context(u8_t idx, const ip6_addr_t *context)
|
---|
| 500 | {
|
---|
| 501 | #if LWIP_6LOWPAN_NUM_CONTEXTS > 0
|
---|
| 502 | if (idx >= LWIP_6LOWPAN_NUM_CONTEXTS) {
|
---|
| 503 | return ERR_ARG;
|
---|
| 504 | }
|
---|
| 505 |
|
---|
| 506 | IP6_ADDR_ZONECHECK(context);
|
---|
| 507 |
|
---|
| 508 | ip6_addr_set(&lowpan6_data.lowpan6_context[idx], context);
|
---|
| 509 |
|
---|
| 510 | return ERR_OK;
|
---|
| 511 | #else
|
---|
| 512 | LWIP_UNUSED_ARG(idx);
|
---|
| 513 | LWIP_UNUSED_ARG(context);
|
---|
| 514 | return ERR_ARG;
|
---|
| 515 | #endif
|
---|
| 516 | }
|
---|
| 517 |
|
---|
| 518 | #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
|
---|
| 519 | /**
|
---|
| 520 | * @ingroup sixlowpan
|
---|
| 521 | * Set short address
|
---|
| 522 | */
|
---|
| 523 | err_t
|
---|
| 524 | lowpan6_set_short_addr(u8_t addr_high, u8_t addr_low)
|
---|
| 525 | {
|
---|
| 526 | short_mac_addr.addr[0] = addr_high;
|
---|
| 527 | short_mac_addr.addr[1] = addr_low;
|
---|
| 528 |
|
---|
| 529 | return ERR_OK;
|
---|
| 530 | }
|
---|
| 531 | #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
|
---|
| 532 |
|
---|
| 533 | /* Create IEEE 802.15.4 address from netif address */
|
---|
| 534 | static err_t
|
---|
| 535 | lowpan6_hwaddr_to_addr(struct netif *netif, struct lowpan6_link_addr *addr)
|
---|
| 536 | {
|
---|
| 537 | addr->addr_len = 8;
|
---|
| 538 | if (netif->hwaddr_len == 8) {
|
---|
| 539 | LWIP_ERROR("NETIF_MAX_HWADDR_LEN >= 8 required", sizeof(netif->hwaddr) >= 8, return ERR_VAL;);
|
---|
| 540 | SMEMCPY(addr->addr, netif->hwaddr, 8);
|
---|
| 541 | } else if (netif->hwaddr_len == 6) {
|
---|
| 542 | /* Copy from MAC-48 */
|
---|
| 543 | SMEMCPY(addr->addr, netif->hwaddr, 3);
|
---|
| 544 | addr->addr[3] = addr->addr[4] = 0xff;
|
---|
| 545 | SMEMCPY(&addr->addr[5], &netif->hwaddr[3], 3);
|
---|
| 546 | } else {
|
---|
| 547 | /* Invalid address length, don't know how to convert this */
|
---|
| 548 | return ERR_VAL;
|
---|
| 549 | }
|
---|
| 550 | return ERR_OK;
|
---|
| 551 | }
|
---|
| 552 |
|
---|
| 553 | /**
|
---|
| 554 | * @ingroup sixlowpan
|
---|
| 555 | * Resolve and fill-in IEEE 802.15.4 address header for outgoing IPv6 packet.
|
---|
| 556 | *
|
---|
| 557 | * Perform Header Compression and fragment if necessary.
|
---|
| 558 | *
|
---|
| 559 | * @param netif The lwIP network interface which the IP packet will be sent on.
|
---|
| 560 | * @param q The pbuf(s) containing the IP packet to be sent.
|
---|
| 561 | * @param ip6addr The IP address of the packet destination.
|
---|
| 562 | *
|
---|
| 563 | * @return err_t
|
---|
| 564 | */
|
---|
| 565 | err_t
|
---|
| 566 | lowpan6_output(struct netif *netif, struct pbuf *q, const ip6_addr_t *ip6addr)
|
---|
| 567 | {
|
---|
| 568 | err_t result;
|
---|
| 569 | const u8_t *hwaddr;
|
---|
| 570 | struct lowpan6_link_addr src, dest;
|
---|
| 571 | #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
|
---|
| 572 | ip6_addr_t ip6_src;
|
---|
| 573 | struct ip6_hdr *ip6_hdr;
|
---|
| 574 | #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
|
---|
| 575 |
|
---|
| 576 | #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
|
---|
| 577 | /* Check if we can compress source address (use aligned copy) */
|
---|
| 578 | ip6_hdr = (struct ip6_hdr *)q->payload;
|
---|
| 579 | ip6_addr_copy_from_packed(ip6_src, ip6_hdr->src);
|
---|
| 580 | ip6_addr_assign_zone(&ip6_src, IP6_UNICAST, netif);
|
---|
| 581 | if (lowpan6_get_address_mode(&ip6_src, &short_mac_addr) == 3) {
|
---|
| 582 | src.addr_len = 2;
|
---|
| 583 | src.addr[0] = short_mac_addr.addr[0];
|
---|
| 584 | src.addr[1] = short_mac_addr.addr[1];
|
---|
| 585 | } else
|
---|
| 586 | #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
|
---|
| 587 | {
|
---|
| 588 | result = lowpan6_hwaddr_to_addr(netif, &src);
|
---|
| 589 | if (result != ERR_OK) {
|
---|
| 590 | MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
|
---|
| 591 | return result;
|
---|
| 592 | }
|
---|
| 593 | }
|
---|
| 594 |
|
---|
| 595 | /* multicast destination IP address? */
|
---|
| 596 | if (ip6_addr_ismulticast(ip6addr)) {
|
---|
| 597 | MIB2_STATS_NETIF_INC(netif, ifoutnucastpkts);
|
---|
| 598 | /* We need to send to the broadcast address.*/
|
---|
| 599 | return lowpan6_frag(netif, q, &src, &ieee_802154_broadcast);
|
---|
| 600 | }
|
---|
| 601 |
|
---|
| 602 | /* We have a unicast destination IP address */
|
---|
| 603 | /* @todo anycast? */
|
---|
| 604 |
|
---|
| 605 | #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
|
---|
| 606 | if (src.addr_len == 2) {
|
---|
| 607 | /* If source address was compressable to short_mac_addr, and dest has same subnet and
|
---|
| 608 | * is also compressable to 2-bytes, assume we can infer dest as a short address too. */
|
---|
| 609 | dest.addr_len = 2;
|
---|
| 610 | dest.addr[0] = ((u8_t *)q->payload)[38];
|
---|
| 611 | dest.addr[1] = ((u8_t *)q->payload)[39];
|
---|
| 612 | if ((src.addr_len == 2) && (ip6_addr_netcmp_zoneless(&ip6_hdr->src, &ip6_hdr->dest)) &&
|
---|
| 613 | (lowpan6_get_address_mode(ip6addr, &dest) == 3)) {
|
---|
| 614 | MIB2_STATS_NETIF_INC(netif, ifoutucastpkts);
|
---|
| 615 | return lowpan6_frag(netif, q, &src, &dest);
|
---|
| 616 | }
|
---|
| 617 | }
|
---|
| 618 | #endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
|
---|
| 619 |
|
---|
| 620 | /* Ask ND6 what to do with the packet. */
|
---|
| 621 | result = nd6_get_next_hop_addr_or_queue(netif, q, ip6addr, &hwaddr);
|
---|
| 622 | if (result != ERR_OK) {
|
---|
| 623 | MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
|
---|
| 624 | return result;
|
---|
| 625 | }
|
---|
| 626 |
|
---|
| 627 | /* If no hardware address is returned, nd6 has queued the packet for later. */
|
---|
| 628 | if (hwaddr == NULL) {
|
---|
| 629 | return ERR_OK;
|
---|
| 630 | }
|
---|
| 631 |
|
---|
| 632 | /* Send out the packet using the returned hardware address. */
|
---|
| 633 | dest.addr_len = netif->hwaddr_len;
|
---|
| 634 | /* XXX: Inferring the length of the source address from the destination address
|
---|
| 635 | * is not correct for IEEE 802.15.4, but currently we don't get this information
|
---|
| 636 | * from the neighbor cache */
|
---|
| 637 | SMEMCPY(dest.addr, hwaddr, netif->hwaddr_len);
|
---|
| 638 | MIB2_STATS_NETIF_INC(netif, ifoutucastpkts);
|
---|
| 639 | return lowpan6_frag(netif, q, &src, &dest);
|
---|
| 640 | }
|
---|
| 641 | /**
|
---|
| 642 | * @ingroup sixlowpan
|
---|
| 643 | * NETIF input function: don't free the input pbuf when returning != ERR_OK!
|
---|
| 644 | */
|
---|
| 645 | err_t
|
---|
| 646 | lowpan6_input(struct pbuf *p, struct netif *netif)
|
---|
| 647 | {
|
---|
| 648 | u8_t *puc, b;
|
---|
| 649 | s8_t i;
|
---|
| 650 | struct lowpan6_link_addr src, dest;
|
---|
| 651 | u16_t datagram_size = 0;
|
---|
| 652 | u16_t datagram_offset, datagram_tag;
|
---|
| 653 | struct lowpan6_reass_helper *lrh, *lrh_next, *lrh_prev = NULL;
|
---|
| 654 |
|
---|
| 655 | if (p == NULL) {
|
---|
| 656 | return ERR_OK;
|
---|
| 657 | }
|
---|
| 658 |
|
---|
| 659 | MIB2_STATS_NETIF_ADD(netif, ifinoctets, p->tot_len);
|
---|
| 660 |
|
---|
| 661 | if (p->len != p->tot_len) {
|
---|
| 662 | /* for now, this needs a pbuf in one piece */
|
---|
| 663 | goto lowpan6_input_discard;
|
---|
| 664 | }
|
---|
| 665 |
|
---|
| 666 | if (lowpan6_parse_iee802154_header(p, &src, &dest) != ERR_OK) {
|
---|
| 667 | goto lowpan6_input_discard;
|
---|
| 668 | }
|
---|
| 669 |
|
---|
| 670 | /* Check dispatch. */
|
---|
| 671 | puc = (u8_t *)p->payload;
|
---|
| 672 |
|
---|
| 673 | b = *puc;
|
---|
| 674 | if ((b & 0xf8) == 0xc0) {
|
---|
| 675 | /* FRAG1 dispatch. add this packet to reassembly list. */
|
---|
| 676 | datagram_size = ((u16_t)(puc[0] & 0x07) << 8) | (u16_t)puc[1];
|
---|
| 677 | datagram_tag = ((u16_t)puc[2] << 8) | (u16_t)puc[3];
|
---|
| 678 |
|
---|
| 679 | /* check for duplicate */
|
---|
| 680 | lrh = lowpan6_data.reass_list;
|
---|
| 681 | while (lrh != NULL) {
|
---|
| 682 | uint8_t discard = 0;
|
---|
| 683 | lrh_next = lrh->next_packet;
|
---|
| 684 | if ((lrh->sender_addr.addr_len == src.addr_len) &&
|
---|
| 685 | (memcmp(lrh->sender_addr.addr, src.addr, src.addr_len) == 0)) {
|
---|
| 686 | /* address match with packet in reassembly. */
|
---|
| 687 | if ((datagram_tag == lrh->datagram_tag) && (datagram_size == lrh->datagram_size)) {
|
---|
| 688 | /* duplicate fragment. */
|
---|
| 689 | goto lowpan6_input_discard;
|
---|
| 690 | } else {
|
---|
| 691 | /* We are receiving the start of a new datagram. Discard old one (incomplete). */
|
---|
| 692 | discard = 1;
|
---|
| 693 | }
|
---|
| 694 | }
|
---|
| 695 | if (discard) {
|
---|
| 696 | dequeue_datagram(lrh, lrh_prev);
|
---|
| 697 | free_reass_datagram(lrh);
|
---|
| 698 | } else {
|
---|
| 699 | lrh_prev = lrh;
|
---|
| 700 | }
|
---|
| 701 | /* Check next datagram in queue. */
|
---|
| 702 | lrh = lrh_next;
|
---|
| 703 | }
|
---|
| 704 |
|
---|
| 705 | pbuf_remove_header(p, 4); /* hide frag1 dispatch */
|
---|
| 706 |
|
---|
| 707 | lrh = (struct lowpan6_reass_helper *) mem_malloc(sizeof(struct lowpan6_reass_helper));
|
---|
| 708 | if (lrh == NULL) {
|
---|
| 709 | goto lowpan6_input_discard;
|
---|
| 710 | }
|
---|
| 711 |
|
---|
| 712 | lrh->sender_addr.addr_len = src.addr_len;
|
---|
| 713 | for (i = 0; i < src.addr_len; i++) {
|
---|
| 714 | lrh->sender_addr.addr[i] = src.addr[i];
|
---|
| 715 | }
|
---|
| 716 | lrh->datagram_size = datagram_size;
|
---|
| 717 | lrh->datagram_tag = datagram_tag;
|
---|
| 718 | lrh->frags = NULL;
|
---|
| 719 | if (*(u8_t *)p->payload == 0x41) {
|
---|
| 720 | /* This is a complete IPv6 packet, just skip dispatch byte. */
|
---|
| 721 | pbuf_remove_header(p, 1); /* hide dispatch byte. */
|
---|
| 722 | lrh->reass = p;
|
---|
| 723 | } else if ((*(u8_t *)p->payload & 0xe0 ) == 0x60) {
|
---|
| 724 | lrh->reass = lowpan6_decompress(p, datagram_size, LWIP_6LOWPAN_CONTEXTS(netif), &src, &dest);
|
---|
| 725 | if (lrh->reass == NULL) {
|
---|
| 726 | /* decompression failed */
|
---|
| 727 | mem_free(lrh);
|
---|
| 728 | goto lowpan6_input_discard;
|
---|
| 729 | }
|
---|
| 730 | }
|
---|
| 731 | /* TODO: handle the case where we already have FRAGN received */
|
---|
| 732 | lrh->next_packet = lowpan6_data.reass_list;
|
---|
| 733 | lrh->timer = 2;
|
---|
| 734 | lowpan6_data.reass_list = lrh;
|
---|
| 735 |
|
---|
| 736 | return ERR_OK;
|
---|
| 737 | } else if ((b & 0xf8) == 0xe0) {
|
---|
| 738 | /* FRAGN dispatch, find packet being reassembled. */
|
---|
| 739 | datagram_size = ((u16_t)(puc[0] & 0x07) << 8) | (u16_t)puc[1];
|
---|
| 740 | datagram_tag = ((u16_t)puc[2] << 8) | (u16_t)puc[3];
|
---|
| 741 | datagram_offset = (u16_t)puc[4] << 3;
|
---|
| 742 | pbuf_remove_header(p, 4); /* hide frag1 dispatch but keep datagram offset for reassembly */
|
---|
| 743 |
|
---|
| 744 | for (lrh = lowpan6_data.reass_list; lrh != NULL; lrh_prev = lrh, lrh = lrh->next_packet) {
|
---|
| 745 | if ((lrh->sender_addr.addr_len == src.addr_len) &&
|
---|
| 746 | (memcmp(lrh->sender_addr.addr, src.addr, src.addr_len) == 0) &&
|
---|
| 747 | (datagram_tag == lrh->datagram_tag) &&
|
---|
| 748 | (datagram_size == lrh->datagram_size)) {
|
---|
| 749 | break;
|
---|
| 750 | }
|
---|
| 751 | }
|
---|
| 752 | if (lrh == NULL) {
|
---|
| 753 | /* rogue fragment */
|
---|
| 754 | goto lowpan6_input_discard;
|
---|
| 755 | }
|
---|
| 756 | /* Insert new pbuf into list of fragments. Each fragment is a pbuf,
|
---|
| 757 | this only works for unchained pbufs. */
|
---|
| 758 | LWIP_ASSERT("p->next == NULL", p->next == NULL);
|
---|
| 759 | if (lrh->reass != NULL) {
|
---|
| 760 | /* FRAG1 already received, check this offset against first len */
|
---|
| 761 | if (datagram_offset < lrh->reass->len) {
|
---|
| 762 | /* fragment overlap, discard old fragments */
|
---|
| 763 | dequeue_datagram(lrh, lrh_prev);
|
---|
| 764 | free_reass_datagram(lrh);
|
---|
| 765 | goto lowpan6_input_discard;
|
---|
| 766 | }
|
---|
| 767 | }
|
---|
| 768 | if (lrh->frags == NULL) {
|
---|
| 769 | /* first FRAGN */
|
---|
| 770 | lrh->frags = p;
|
---|
| 771 | } else {
|
---|
| 772 | /* find the correct place to insert */
|
---|
| 773 | struct pbuf *q, *last;
|
---|
| 774 | u16_t new_frag_len = p->len - 1; /* p->len includes datagram_offset byte */
|
---|
| 775 | for (q = lrh->frags, last = NULL; q != NULL; last = q, q = q->next) {
|
---|
| 776 | u16_t q_datagram_offset = ((u8_t *)q->payload)[0] << 3;
|
---|
| 777 | u16_t q_frag_len = q->len - 1;
|
---|
| 778 | if (datagram_offset < q_datagram_offset) {
|
---|
| 779 | if (datagram_offset + new_frag_len > q_datagram_offset) {
|
---|
| 780 | /* overlap, discard old fragments */
|
---|
| 781 | dequeue_datagram(lrh, lrh_prev);
|
---|
| 782 | free_reass_datagram(lrh);
|
---|
| 783 | goto lowpan6_input_discard;
|
---|
| 784 | }
|
---|
| 785 | /* insert here */
|
---|
| 786 | break;
|
---|
| 787 | } else if (datagram_offset == q_datagram_offset) {
|
---|
| 788 | if (q_frag_len != new_frag_len) {
|
---|
| 789 | /* fragment mismatch, discard old fragments */
|
---|
| 790 | dequeue_datagram(lrh, lrh_prev);
|
---|
| 791 | free_reass_datagram(lrh);
|
---|
| 792 | goto lowpan6_input_discard;
|
---|
| 793 | }
|
---|
| 794 | /* duplicate, ignore */
|
---|
| 795 | pbuf_free(p);
|
---|
| 796 | return ERR_OK;
|
---|
| 797 | }
|
---|
| 798 | }
|
---|
| 799 | /* insert fragment */
|
---|
| 800 | if (last == NULL) {
|
---|
| 801 | lrh->frags = p;
|
---|
| 802 | } else {
|
---|
| 803 | last->next = p;
|
---|
| 804 | p->next = q;
|
---|
| 805 | }
|
---|
| 806 | }
|
---|
| 807 | /* check if all fragments were received */
|
---|
| 808 | if (lrh->reass) {
|
---|
| 809 | u16_t offset = lrh->reass->len;
|
---|
| 810 | struct pbuf *q;
|
---|
| 811 | for (q = lrh->frags; q != NULL; q = q->next) {
|
---|
| 812 | u16_t q_datagram_offset = ((u8_t *)q->payload)[0] << 3;
|
---|
| 813 | if (q_datagram_offset != offset) {
|
---|
| 814 | /* not complete, wait for more fragments */
|
---|
| 815 | return ERR_OK;
|
---|
| 816 | }
|
---|
| 817 | offset += q->len - 1;
|
---|
| 818 | }
|
---|
| 819 | if (offset == datagram_size) {
|
---|
| 820 | /* all fragments received, combine pbufs */
|
---|
| 821 | u16_t datagram_left = datagram_size - lrh->reass->len;
|
---|
| 822 | for (q = lrh->frags; q != NULL; q = q->next) {
|
---|
| 823 | /* hide datagram_offset byte now */
|
---|
| 824 | pbuf_remove_header(q, 1);
|
---|
| 825 | q->tot_len = datagram_left;
|
---|
| 826 | datagram_left -= q->len;
|
---|
| 827 | }
|
---|
| 828 | LWIP_ASSERT("datagram_left == 0", datagram_left == 0);
|
---|
| 829 | q = lrh->reass;
|
---|
| 830 | q->tot_len = datagram_size;
|
---|
| 831 | q->next = lrh->frags;
|
---|
| 832 | lrh->frags = NULL;
|
---|
| 833 | lrh->reass = NULL;
|
---|
| 834 | dequeue_datagram(lrh, lrh_prev);
|
---|
| 835 | mem_free(lrh);
|
---|
| 836 |
|
---|
| 837 | /* @todo: distinguish unicast/multicast */
|
---|
| 838 | MIB2_STATS_NETIF_INC(netif, ifinucastpkts);
|
---|
| 839 | return ip6_input(q, netif);
|
---|
| 840 | }
|
---|
| 841 | }
|
---|
| 842 | /* pbuf enqueued, waiting for more fragments */
|
---|
| 843 | return ERR_OK;
|
---|
| 844 | } else {
|
---|
| 845 | if (b == 0x41) {
|
---|
| 846 | /* This is a complete IPv6 packet, just skip dispatch byte. */
|
---|
| 847 | pbuf_remove_header(p, 1); /* hide dispatch byte. */
|
---|
| 848 | } else if ((b & 0xe0 ) == 0x60) {
|
---|
| 849 | /* IPv6 headers are compressed using IPHC. */
|
---|
| 850 | p = lowpan6_decompress(p, datagram_size, LWIP_6LOWPAN_CONTEXTS(netif), &src, &dest);
|
---|
| 851 | if (p == NULL) {
|
---|
| 852 | MIB2_STATS_NETIF_INC(netif, ifindiscards);
|
---|
| 853 | return ERR_OK;
|
---|
| 854 | }
|
---|
| 855 | } else {
|
---|
| 856 | goto lowpan6_input_discard;
|
---|
| 857 | }
|
---|
| 858 |
|
---|
| 859 | /* @todo: distinguish unicast/multicast */
|
---|
| 860 | MIB2_STATS_NETIF_INC(netif, ifinucastpkts);
|
---|
| 861 |
|
---|
| 862 | return ip6_input(p, netif);
|
---|
| 863 | }
|
---|
| 864 | lowpan6_input_discard:
|
---|
| 865 | MIB2_STATS_NETIF_INC(netif, ifindiscards);
|
---|
| 866 | pbuf_free(p);
|
---|
| 867 | /* always return ERR_OK here to prevent the caller freeing the pbuf */
|
---|
| 868 | return ERR_OK;
|
---|
| 869 | }
|
---|
| 870 |
|
---|
| 871 | /**
|
---|
| 872 | * @ingroup sixlowpan
|
---|
| 873 | */
|
---|
| 874 | err_t
|
---|
| 875 | lowpan6_if_init(struct netif *netif)
|
---|
| 876 | {
|
---|
| 877 | netif->name[0] = 'L';
|
---|
| 878 | netif->name[1] = '6';
|
---|
| 879 | netif->output_ip6 = lowpan6_output;
|
---|
| 880 |
|
---|
| 881 | MIB2_INIT_NETIF(netif, snmp_ifType_other, 0);
|
---|
| 882 |
|
---|
| 883 | /* maximum transfer unit */
|
---|
| 884 | netif->mtu = 1280;
|
---|
| 885 |
|
---|
| 886 | /* broadcast capability */
|
---|
| 887 | netif->flags = NETIF_FLAG_BROADCAST /* | NETIF_FLAG_LOWPAN6 */;
|
---|
| 888 |
|
---|
| 889 | return ERR_OK;
|
---|
| 890 | }
|
---|
| 891 |
|
---|
| 892 | /**
|
---|
| 893 | * @ingroup sixlowpan
|
---|
| 894 | * Set PAN ID
|
---|
| 895 | */
|
---|
| 896 | err_t
|
---|
| 897 | lowpan6_set_pan_id(u16_t pan_id)
|
---|
| 898 | {
|
---|
| 899 | lowpan6_data.ieee_802154_pan_id = pan_id;
|
---|
| 900 |
|
---|
| 901 | return ERR_OK;
|
---|
| 902 | }
|
---|
| 903 |
|
---|
| 904 | #if !NO_SYS
|
---|
| 905 | /**
|
---|
| 906 | * @ingroup sixlowpan
|
---|
| 907 | * Pass a received packet to tcpip_thread for input processing
|
---|
| 908 | *
|
---|
| 909 | * @param p the received packet, p->payload pointing to the
|
---|
| 910 | * IEEE 802.15.4 header.
|
---|
| 911 | * @param inp the network interface on which the packet was received
|
---|
| 912 | */
|
---|
| 913 | err_t
|
---|
| 914 | tcpip_6lowpan_input(struct pbuf *p, struct netif *inp)
|
---|
| 915 | {
|
---|
| 916 | return tcpip_inpkt(p, inp, lowpan6_input);
|
---|
| 917 | }
|
---|
| 918 | #endif /* !NO_SYS */
|
---|
| 919 |
|
---|
| 920 | #endif /* LWIP_IPV6 */
|
---|