1 /* 2 * Copyright 2011, Siemens AG 3 * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com> 4 */ 5 6 /* 7 * Based on patches from Jon Smirl <jonsmirl@gmail.com> 8 * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com> 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 12 * as published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License along 20 * with this program; if not, write to the Free Software Foundation, Inc., 21 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 22 */ 23 24 /* Jon's code is based on 6lowpan implementation for Contiki which is: 25 * Copyright (c) 2008, Swedish Institute of Computer Science. 26 * All rights reserved. 27 * 28 * Redistribution and use in source and binary forms, with or without 29 * modification, are permitted provided that the following conditions 30 * are met: 31 * 1. Redistributions of source code must retain the above copyright 32 * notice, this list of conditions and the following disclaimer. 33 * 2. Redistributions in binary form must reproduce the above copyright 34 * notice, this list of conditions and the following disclaimer in the 35 * documentation and/or other materials provided with the distribution. 36 * 3. Neither the name of the Institute nor the names of its contributors 37 * may be used to endorse or promote products derived from this software 38 * without specific prior written permission. 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 */ 52 53 #ifndef __6LOWPAN_H__ 54 #define __6LOWPAN_H__ 55 56 #include <net/ipv6.h> 57 58 #define UIP_802154_SHORTADDR_LEN 2 /* compressed ipv6 address length */ 59 #define UIP_IPH_LEN 40 /* ipv6 fixed header size */ 60 #define UIP_PROTO_UDP 17 /* ipv6 next header value for UDP */ 61 #define UIP_FRAGH_LEN 8 /* ipv6 fragment header size */ 62 63 /* 64 * ipv6 address based on mac 65 * second bit-flip (Universe/Local) is done according RFC2464 66 */ 67 #define is_addr_mac_addr_based(a, m) \ 68 ((((a)->s6_addr[8]) == (((m)[0]) ^ 0x02)) && \ 69 (((a)->s6_addr[9]) == (m)[1]) && \ 70 (((a)->s6_addr[10]) == (m)[2]) && \ 71 (((a)->s6_addr[11]) == (m)[3]) && \ 72 (((a)->s6_addr[12]) == (m)[4]) && \ 73 (((a)->s6_addr[13]) == (m)[5]) && \ 74 (((a)->s6_addr[14]) == (m)[6]) && \ 75 (((a)->s6_addr[15]) == (m)[7])) 76 77 /* ipv6 address is unspecified */ 78 #define is_addr_unspecified(a) \ 79 ((((a)->s6_addr32[0]) == 0) && \ 80 (((a)->s6_addr32[1]) == 0) && \ 81 (((a)->s6_addr32[2]) == 0) && \ 82 (((a)->s6_addr32[3]) == 0)) 83 84 /* compare ipv6 addresses prefixes */ 85 #define ipaddr_prefixcmp(addr1, addr2, length) \ 86 (memcmp(addr1, addr2, length >> 3) == 0) 87 88 /* local link, i.e. FE80::/10 */ 89 #define is_addr_link_local(a) (((a)->s6_addr16[0]) == htons(0xFE80)) 90 91 /* 92 * check whether we can compress the IID to 16 bits, 93 * it's possible for unicast adresses with first 49 bits are zero only. 94 */ 95 #define lowpan_is_iid_16_bit_compressable(a) \ 96 ((((a)->s6_addr16[4]) == 0) && \ 97 (((a)->s6_addr[10]) == 0) && \ 98 (((a)->s6_addr[11]) == 0xff) && \ 99 (((a)->s6_addr[12]) == 0xfe) && \ 100 (((a)->s6_addr[13]) == 0)) 101 102 /* multicast address */ 103 #define is_addr_mcast(a) (((a)->s6_addr[0]) == 0xFF) 104 105 /* check whether the 112-bit gid of the multicast address is mappable to: */ 106 107 /* 9 bits, for FF02::1 (all nodes) and FF02::2 (all routers) addresses only. */ 108 #define lowpan_is_mcast_addr_compressable(a) \ 109 ((((a)->s6_addr16[1]) == 0) && \ 110 (((a)->s6_addr16[2]) == 0) && \ 111 (((a)->s6_addr16[3]) == 0) && \ 112 (((a)->s6_addr16[4]) == 0) && \ 113 (((a)->s6_addr16[5]) == 0) && \ 114 (((a)->s6_addr16[6]) == 0) && \ 115 (((a)->s6_addr[14]) == 0) && \ 116 ((((a)->s6_addr[15]) == 1) || (((a)->s6_addr[15]) == 2))) 117 118 /* 48 bits, FFXX::00XX:XXXX:XXXX */ 119 #define lowpan_is_mcast_addr_compressable48(a) \ 120 ((((a)->s6_addr16[1]) == 0) && \ 121 (((a)->s6_addr16[2]) == 0) && \ 122 (((a)->s6_addr16[3]) == 0) && \ 123 (((a)->s6_addr16[4]) == 0) && \ 124 (((a)->s6_addr[10]) == 0)) 125 126 /* 32 bits, FFXX::00XX:XXXX */ 127 #define lowpan_is_mcast_addr_compressable32(a) \ 128 ((((a)->s6_addr16[1]) == 0) && \ 129 (((a)->s6_addr16[2]) == 0) && \ 130 (((a)->s6_addr16[3]) == 0) && \ 131 (((a)->s6_addr16[4]) == 0) && \ 132 (((a)->s6_addr16[5]) == 0) && \ 133 (((a)->s6_addr[12]) == 0)) 134 135 /* 8 bits, FF02::00XX */ 136 #define lowpan_is_mcast_addr_compressable8(a) \ 137 ((((a)->s6_addr[1]) == 2) && \ 138 (((a)->s6_addr16[1]) == 0) && \ 139 (((a)->s6_addr16[2]) == 0) && \ 140 (((a)->s6_addr16[3]) == 0) && \ 141 (((a)->s6_addr16[4]) == 0) && \ 142 (((a)->s6_addr16[5]) == 0) && \ 143 (((a)->s6_addr16[6]) == 0) && \ 144 (((a)->s6_addr[14]) == 0)) 145 146 #define lowpan_is_addr_broadcast(a) \ 147 ((((a)[0]) == 0xFF) && \ 148 (((a)[1]) == 0xFF) && \ 149 (((a)[2]) == 0xFF) && \ 150 (((a)[3]) == 0xFF) && \ 151 (((a)[4]) == 0xFF) && \ 152 (((a)[5]) == 0xFF) && \ 153 (((a)[6]) == 0xFF) && \ 154 (((a)[7]) == 0xFF)) 155 156 #define LOWPAN_DISPATCH_IPV6 0x41 /* 01000001 = 65 */ 157 #define LOWPAN_DISPATCH_HC1 0x42 /* 01000010 = 66 */ 158 #define LOWPAN_DISPATCH_IPHC 0x60 /* 011xxxxx = ... */ 159 #define LOWPAN_DISPATCH_FRAG1 0xc0 /* 11000xxx */ 160 #define LOWPAN_DISPATCH_FRAGN 0xe0 /* 11100xxx */ 161 162 #define LOWPAN_DISPATCH_MASK 0xf8 /* 11111000 */ 163 164 #define LOWPAN_FRAG_TIMEOUT (HZ * 60) /* time-out 60 sec */ 165 166 #define LOWPAN_FRAG1_HEAD_SIZE 0x4 167 #define LOWPAN_FRAGN_HEAD_SIZE 0x5 168 169 /* 170 * According IEEE802.15.4 standard: 171 * - MTU is 127 octets 172 * - maximum MHR size is 37 octets 173 * - MFR size is 2 octets 174 * 175 * so minimal payload size that we may guarantee is: 176 * MTU - MHR - MFR = 88 octets 177 */ 178 #define LOWPAN_FRAG_SIZE 88 179 180 /* 181 * Values of fields within the IPHC encoding first byte 182 * (C stands for compressed and I for inline) 183 */ 184 #define LOWPAN_IPHC_TF 0x18 185 186 #define LOWPAN_IPHC_FL_C 0x10 187 #define LOWPAN_IPHC_TC_C 0x08 188 #define LOWPAN_IPHC_NH_C 0x04 189 #define LOWPAN_IPHC_TTL_1 0x01 190 #define LOWPAN_IPHC_TTL_64 0x02 191 #define LOWPAN_IPHC_TTL_255 0x03 192 #define LOWPAN_IPHC_TTL_I 0x00 193 194 195 /* Values of fields within the IPHC encoding second byte */ 196 #define LOWPAN_IPHC_CID 0x80 197 198 #define LOWPAN_IPHC_ADDR_00 0x00 199 #define LOWPAN_IPHC_ADDR_01 0x01 200 #define LOWPAN_IPHC_ADDR_02 0x02 201 #define LOWPAN_IPHC_ADDR_03 0x03 202 203 #define LOWPAN_IPHC_SAC 0x40 204 #define LOWPAN_IPHC_SAM 0x30 205 206 #define LOWPAN_IPHC_SAM_BIT 4 207 208 #define LOWPAN_IPHC_M 0x08 209 #define LOWPAN_IPHC_DAC 0x04 210 #define LOWPAN_IPHC_DAM_00 0x00 211 #define LOWPAN_IPHC_DAM_01 0x01 212 #define LOWPAN_IPHC_DAM_10 0x02 213 #define LOWPAN_IPHC_DAM_11 0x03 214 215 #define LOWPAN_IPHC_DAM_BIT 0 216 /* 217 * LOWPAN_UDP encoding (works together with IPHC) 218 */ 219 #define LOWPAN_NHC_UDP_MASK 0xF8 220 #define LOWPAN_NHC_UDP_ID 0xF0 221 #define LOWPAN_NHC_UDP_CHECKSUMC 0x04 222 #define LOWPAN_NHC_UDP_CHECKSUMI 0x00 223 224 #define LOWPAN_NHC_UDP_4BIT_PORT 0xF0B0 225 #define LOWPAN_NHC_UDP_4BIT_MASK 0xFFF0 226 #define LOWPAN_NHC_UDP_8BIT_PORT 0xF000 227 #define LOWPAN_NHC_UDP_8BIT_MASK 0xFF00 228 229 /* values for port compression, _with checksum_ ie bit 5 set to 0 */ 230 #define LOWPAN_NHC_UDP_CS_P_00 0xF0 /* all inline */ 231 #define LOWPAN_NHC_UDP_CS_P_01 0xF1 /* source 16bit inline, 232 dest = 0xF0 + 8 bit inline */ 233 #define LOWPAN_NHC_UDP_CS_P_10 0xF2 /* source = 0xF0 + 8bit inline, 234 dest = 16 bit inline */ 235 #define LOWPAN_NHC_UDP_CS_P_11 0xF3 /* source & dest = 0xF0B + 4bit inline */ 236 #define LOWPAN_NHC_UDP_CS_C 0x04 /* checksum elided */ 237 238 #ifdef DEBUG 239 /* print data in line */ 240 static inline void raw_dump_inline(const char *caller, char *msg, 241 unsigned char *buf, int len) 242 { 243 if (msg) 244 pr_debug("%s():%s: ", caller, msg); 245 246 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, buf, len, false); 247 } 248 249 /* print data in a table format: 250 * 251 * addr: xx xx xx xx xx xx 252 * addr: xx xx xx xx xx xx 253 * ... 254 */ 255 static inline void raw_dump_table(const char *caller, char *msg, 256 unsigned char *buf, int len) 257 { 258 if (msg) 259 pr_debug("%s():%s:\n", caller, msg); 260 261 print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET, 16, 1, buf, len, false); 262 } 263 #else 264 static inline void raw_dump_table(const char *caller, char *msg, 265 unsigned char *buf, int len) { } 266 static inline void raw_dump_inline(const char *caller, char *msg, 267 unsigned char *buf, int len) { } 268 #endif 269 270 static inline int lowpan_fetch_skb_u8(struct sk_buff *skb, u8 *val) 271 { 272 if (unlikely(!pskb_may_pull(skb, 1))) 273 return -EINVAL; 274 275 *val = skb->data[0]; 276 skb_pull(skb, 1); 277 278 return 0; 279 } 280 281 static inline int lowpan_fetch_skb_u16(struct sk_buff *skb, u16 *val) 282 { 283 if (unlikely(!pskb_may_pull(skb, 2))) 284 return -EINVAL; 285 286 *val = (skb->data[0] << 8) | skb->data[1]; 287 skb_pull(skb, 2); 288 289 return 0; 290 } 291 292 static inline bool lowpan_fetch_skb(struct sk_buff *skb, 293 void *data, const unsigned int len) 294 { 295 if (unlikely(!pskb_may_pull(skb, len))) 296 return true; 297 298 skb_copy_from_linear_data(skb, data, len); 299 skb_pull(skb, len); 300 301 return false; 302 } 303 304 static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data, 305 const size_t len) 306 { 307 memcpy(*hc_ptr, data, len); 308 *hc_ptr += len; 309 } 310 311 static inline u8 lowpan_addr_mode_size(const u8 addr_mode) 312 { 313 static const u8 addr_sizes[] = { 314 [LOWPAN_IPHC_ADDR_00] = 16, 315 [LOWPAN_IPHC_ADDR_01] = 8, 316 [LOWPAN_IPHC_ADDR_02] = 2, 317 [LOWPAN_IPHC_ADDR_03] = 0, 318 }; 319 return addr_sizes[addr_mode]; 320 } 321 322 static inline u8 lowpan_next_hdr_size(const u8 h_enc, u16 *uncomp_header) 323 { 324 u8 ret = 1; 325 326 if ((h_enc & LOWPAN_NHC_UDP_MASK) == LOWPAN_NHC_UDP_ID) { 327 *uncomp_header += sizeof(struct udphdr); 328 329 switch (h_enc & LOWPAN_NHC_UDP_CS_P_11) { 330 case LOWPAN_NHC_UDP_CS_P_00: 331 ret += 4; 332 break; 333 case LOWPAN_NHC_UDP_CS_P_01: 334 case LOWPAN_NHC_UDP_CS_P_10: 335 ret += 3; 336 break; 337 case LOWPAN_NHC_UDP_CS_P_11: 338 ret++; 339 break; 340 default: 341 break; 342 } 343 344 if (!(h_enc & LOWPAN_NHC_UDP_CS_C)) 345 ret += 2; 346 } 347 348 return ret; 349 } 350 351 /** 352 * lowpan_uncompress_size - returns skb->len size with uncompressed header 353 * @skb: sk_buff with 6lowpan header inside 354 * @datagram_offset: optional to get the datagram_offset value 355 * 356 * Returns the skb->len with uncompressed header 357 */ 358 static inline u16 359 lowpan_uncompress_size(const struct sk_buff *skb, u16 *dgram_offset) 360 { 361 u16 ret = 2, uncomp_header = sizeof(struct ipv6hdr); 362 u8 iphc0, iphc1, h_enc; 363 364 iphc0 = skb_network_header(skb)[0]; 365 iphc1 = skb_network_header(skb)[1]; 366 367 switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) { 368 case 0: 369 ret += 4; 370 break; 371 case 1: 372 ret += 3; 373 break; 374 case 2: 375 ret++; 376 break; 377 default: 378 break; 379 } 380 381 if (!(iphc0 & LOWPAN_IPHC_NH_C)) 382 ret++; 383 384 if (!(iphc0 & 0x03)) 385 ret++; 386 387 ret += lowpan_addr_mode_size((iphc1 & LOWPAN_IPHC_SAM) >> 388 LOWPAN_IPHC_SAM_BIT); 389 390 if (iphc1 & LOWPAN_IPHC_M) { 391 switch ((iphc1 & LOWPAN_IPHC_DAM_11) >> 392 LOWPAN_IPHC_DAM_BIT) { 393 case LOWPAN_IPHC_DAM_00: 394 ret += 16; 395 break; 396 case LOWPAN_IPHC_DAM_01: 397 ret += 6; 398 break; 399 case LOWPAN_IPHC_DAM_10: 400 ret += 4; 401 break; 402 case LOWPAN_IPHC_DAM_11: 403 ret++; 404 break; 405 default: 406 break; 407 } 408 } else { 409 ret += lowpan_addr_mode_size((iphc1 & LOWPAN_IPHC_DAM_11) >> 410 LOWPAN_IPHC_DAM_BIT); 411 } 412 413 if (iphc0 & LOWPAN_IPHC_NH_C) { 414 h_enc = skb_network_header(skb)[ret]; 415 ret += lowpan_next_hdr_size(h_enc, &uncomp_header); 416 } 417 418 if (dgram_offset) 419 *dgram_offset = uncomp_header; 420 421 return skb->len + uncomp_header - ret; 422 } 423 424 typedef int (*skb_delivery_cb)(struct sk_buff *skb, struct net_device *dev); 425 426 int lowpan_process_data(struct sk_buff *skb, struct net_device *dev, 427 const u8 *saddr, const u8 saddr_type, const u8 saddr_len, 428 const u8 *daddr, const u8 daddr_type, const u8 daddr_len, 429 u8 iphc0, u8 iphc1, skb_delivery_cb skb_deliver); 430 int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev, 431 unsigned short type, const void *_daddr, 432 const void *_saddr, unsigned int len); 433 434 #endif /* __6LOWPAN_H__ */ 435