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 #include <net/net_namespace.h> 58 59 #define UIP_802154_SHORTADDR_LEN 2 /* compressed ipv6 address length */ 60 #define UIP_IPH_LEN 40 /* ipv6 fixed header size */ 61 #define UIP_PROTO_UDP 17 /* ipv6 next header value for UDP */ 62 #define UIP_FRAGH_LEN 8 /* ipv6 fragment header size */ 63 64 /* 65 * ipv6 address based on mac 66 * second bit-flip (Universe/Local) is done according RFC2464 67 */ 68 #define is_addr_mac_addr_based(a, m) \ 69 ((((a)->s6_addr[8]) == (((m)[0]) ^ 0x02)) && \ 70 (((a)->s6_addr[9]) == (m)[1]) && \ 71 (((a)->s6_addr[10]) == (m)[2]) && \ 72 (((a)->s6_addr[11]) == (m)[3]) && \ 73 (((a)->s6_addr[12]) == (m)[4]) && \ 74 (((a)->s6_addr[13]) == (m)[5]) && \ 75 (((a)->s6_addr[14]) == (m)[6]) && \ 76 (((a)->s6_addr[15]) == (m)[7])) 77 78 /* ipv6 address is unspecified */ 79 #define is_addr_unspecified(a) \ 80 ((((a)->s6_addr32[0]) == 0) && \ 81 (((a)->s6_addr32[1]) == 0) && \ 82 (((a)->s6_addr32[2]) == 0) && \ 83 (((a)->s6_addr32[3]) == 0)) 84 85 /* compare ipv6 addresses prefixes */ 86 #define ipaddr_prefixcmp(addr1, addr2, length) \ 87 (memcmp(addr1, addr2, length >> 3) == 0) 88 89 /* local link, i.e. FE80::/10 */ 90 #define is_addr_link_local(a) (((a)->s6_addr16[0]) == htons(0xFE80)) 91 92 /* 93 * check whether we can compress the IID to 16 bits, 94 * it's possible for unicast adresses with first 49 bits are zero only. 95 */ 96 #define lowpan_is_iid_16_bit_compressable(a) \ 97 ((((a)->s6_addr16[4]) == 0) && \ 98 (((a)->s6_addr[10]) == 0) && \ 99 (((a)->s6_addr[11]) == 0xff) && \ 100 (((a)->s6_addr[12]) == 0xfe) && \ 101 (((a)->s6_addr[13]) == 0)) 102 103 /* multicast address */ 104 #define is_addr_mcast(a) (((a)->s6_addr[0]) == 0xFF) 105 106 /* check whether the 112-bit gid of the multicast address is mappable to: */ 107 108 /* 9 bits, for FF02::1 (all nodes) and FF02::2 (all routers) addresses only. */ 109 #define lowpan_is_mcast_addr_compressable(a) \ 110 ((((a)->s6_addr16[1]) == 0) && \ 111 (((a)->s6_addr16[2]) == 0) && \ 112 (((a)->s6_addr16[3]) == 0) && \ 113 (((a)->s6_addr16[4]) == 0) && \ 114 (((a)->s6_addr16[5]) == 0) && \ 115 (((a)->s6_addr16[6]) == 0) && \ 116 (((a)->s6_addr[14]) == 0) && \ 117 ((((a)->s6_addr[15]) == 1) || (((a)->s6_addr[15]) == 2))) 118 119 /* 48 bits, FFXX::00XX:XXXX:XXXX */ 120 #define lowpan_is_mcast_addr_compressable48(a) \ 121 ((((a)->s6_addr16[1]) == 0) && \ 122 (((a)->s6_addr16[2]) == 0) && \ 123 (((a)->s6_addr16[3]) == 0) && \ 124 (((a)->s6_addr16[4]) == 0) && \ 125 (((a)->s6_addr[10]) == 0)) 126 127 /* 32 bits, FFXX::00XX:XXXX */ 128 #define lowpan_is_mcast_addr_compressable32(a) \ 129 ((((a)->s6_addr16[1]) == 0) && \ 130 (((a)->s6_addr16[2]) == 0) && \ 131 (((a)->s6_addr16[3]) == 0) && \ 132 (((a)->s6_addr16[4]) == 0) && \ 133 (((a)->s6_addr16[5]) == 0) && \ 134 (((a)->s6_addr[12]) == 0)) 135 136 /* 8 bits, FF02::00XX */ 137 #define lowpan_is_mcast_addr_compressable8(a) \ 138 ((((a)->s6_addr[1]) == 2) && \ 139 (((a)->s6_addr16[1]) == 0) && \ 140 (((a)->s6_addr16[2]) == 0) && \ 141 (((a)->s6_addr16[3]) == 0) && \ 142 (((a)->s6_addr16[4]) == 0) && \ 143 (((a)->s6_addr16[5]) == 0) && \ 144 (((a)->s6_addr16[6]) == 0) && \ 145 (((a)->s6_addr[14]) == 0)) 146 147 #define lowpan_is_addr_broadcast(a) \ 148 ((((a)[0]) == 0xFF) && \ 149 (((a)[1]) == 0xFF) && \ 150 (((a)[2]) == 0xFF) && \ 151 (((a)[3]) == 0xFF) && \ 152 (((a)[4]) == 0xFF) && \ 153 (((a)[5]) == 0xFF) && \ 154 (((a)[6]) == 0xFF) && \ 155 (((a)[7]) == 0xFF)) 156 157 #define LOWPAN_DISPATCH_IPV6 0x41 /* 01000001 = 65 */ 158 #define LOWPAN_DISPATCH_HC1 0x42 /* 01000010 = 66 */ 159 #define LOWPAN_DISPATCH_IPHC 0x60 /* 011xxxxx = ... */ 160 #define LOWPAN_DISPATCH_FRAG1 0xc0 /* 11000xxx */ 161 #define LOWPAN_DISPATCH_FRAGN 0xe0 /* 11100xxx */ 162 163 #define LOWPAN_DISPATCH_MASK 0xf8 /* 11111000 */ 164 165 #define LOWPAN_FRAG_TIMEOUT (HZ * 60) /* time-out 60 sec */ 166 167 #define LOWPAN_FRAG1_HEAD_SIZE 0x4 168 #define LOWPAN_FRAGN_HEAD_SIZE 0x5 169 170 /* 171 * According IEEE802.15.4 standard: 172 * - MTU is 127 octets 173 * - maximum MHR size is 37 octets 174 * - MFR size is 2 octets 175 * 176 * so minimal payload size that we may guarantee is: 177 * MTU - MHR - MFR = 88 octets 178 */ 179 #define LOWPAN_FRAG_SIZE 88 180 181 /* 182 * Values of fields within the IPHC encoding first byte 183 * (C stands for compressed and I for inline) 184 */ 185 #define LOWPAN_IPHC_TF 0x18 186 187 #define LOWPAN_IPHC_FL_C 0x10 188 #define LOWPAN_IPHC_TC_C 0x08 189 #define LOWPAN_IPHC_NH_C 0x04 190 #define LOWPAN_IPHC_TTL_1 0x01 191 #define LOWPAN_IPHC_TTL_64 0x02 192 #define LOWPAN_IPHC_TTL_255 0x03 193 #define LOWPAN_IPHC_TTL_I 0x00 194 195 196 /* Values of fields within the IPHC encoding second byte */ 197 #define LOWPAN_IPHC_CID 0x80 198 199 #define LOWPAN_IPHC_ADDR_00 0x00 200 #define LOWPAN_IPHC_ADDR_01 0x01 201 #define LOWPAN_IPHC_ADDR_02 0x02 202 #define LOWPAN_IPHC_ADDR_03 0x03 203 204 #define LOWPAN_IPHC_SAC 0x40 205 #define LOWPAN_IPHC_SAM 0x30 206 207 #define LOWPAN_IPHC_SAM_BIT 4 208 209 #define LOWPAN_IPHC_M 0x08 210 #define LOWPAN_IPHC_DAC 0x04 211 #define LOWPAN_IPHC_DAM_00 0x00 212 #define LOWPAN_IPHC_DAM_01 0x01 213 #define LOWPAN_IPHC_DAM_10 0x02 214 #define LOWPAN_IPHC_DAM_11 0x03 215 216 #define LOWPAN_IPHC_DAM_BIT 0 217 /* 218 * LOWPAN_UDP encoding (works together with IPHC) 219 */ 220 #define LOWPAN_NHC_UDP_MASK 0xF8 221 #define LOWPAN_NHC_UDP_ID 0xF0 222 #define LOWPAN_NHC_UDP_CHECKSUMC 0x04 223 #define LOWPAN_NHC_UDP_CHECKSUMI 0x00 224 225 #define LOWPAN_NHC_UDP_4BIT_PORT 0xF0B0 226 #define LOWPAN_NHC_UDP_4BIT_MASK 0xFFF0 227 #define LOWPAN_NHC_UDP_8BIT_PORT 0xF000 228 #define LOWPAN_NHC_UDP_8BIT_MASK 0xFF00 229 230 /* values for port compression, _with checksum_ ie bit 5 set to 0 */ 231 #define LOWPAN_NHC_UDP_CS_P_00 0xF0 /* all inline */ 232 #define LOWPAN_NHC_UDP_CS_P_01 0xF1 /* source 16bit inline, 233 dest = 0xF0 + 8 bit inline */ 234 #define LOWPAN_NHC_UDP_CS_P_10 0xF2 /* source = 0xF0 + 8bit inline, 235 dest = 16 bit inline */ 236 #define LOWPAN_NHC_UDP_CS_P_11 0xF3 /* source & dest = 0xF0B + 4bit inline */ 237 #define LOWPAN_NHC_UDP_CS_C 0x04 /* checksum elided */ 238 239 #ifdef DEBUG 240 /* print data in line */ 241 static inline void raw_dump_inline(const char *caller, char *msg, 242 unsigned char *buf, int len) 243 { 244 if (msg) 245 pr_debug("%s():%s: ", caller, msg); 246 247 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, buf, len, false); 248 } 249 250 /* print data in a table format: 251 * 252 * addr: xx xx xx xx xx xx 253 * addr: xx xx xx xx xx xx 254 * ... 255 */ 256 static inline void raw_dump_table(const char *caller, char *msg, 257 unsigned char *buf, int len) 258 { 259 if (msg) 260 pr_debug("%s():%s:\n", caller, msg); 261 262 print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET, 16, 1, buf, len, false); 263 } 264 #else 265 static inline void raw_dump_table(const char *caller, char *msg, 266 unsigned char *buf, int len) { } 267 static inline void raw_dump_inline(const char *caller, char *msg, 268 unsigned char *buf, int len) { } 269 #endif 270 271 static inline int lowpan_fetch_skb_u8(struct sk_buff *skb, u8 *val) 272 { 273 if (unlikely(!pskb_may_pull(skb, 1))) 274 return -EINVAL; 275 276 *val = skb->data[0]; 277 skb_pull(skb, 1); 278 279 return 0; 280 } 281 282 static inline int lowpan_fetch_skb_u16(struct sk_buff *skb, u16 *val) 283 { 284 if (unlikely(!pskb_may_pull(skb, 2))) 285 return -EINVAL; 286 287 *val = (skb->data[0] << 8) | skb->data[1]; 288 skb_pull(skb, 2); 289 290 return 0; 291 } 292 293 static inline bool lowpan_fetch_skb(struct sk_buff *skb, 294 void *data, const unsigned int len) 295 { 296 if (unlikely(!pskb_may_pull(skb, len))) 297 return true; 298 299 skb_copy_from_linear_data(skb, data, len); 300 skb_pull(skb, len); 301 302 return false; 303 } 304 305 static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data, 306 const size_t len) 307 { 308 memcpy(*hc_ptr, data, len); 309 *hc_ptr += len; 310 } 311 312 static inline u8 lowpan_addr_mode_size(const u8 addr_mode) 313 { 314 static const u8 addr_sizes[] = { 315 [LOWPAN_IPHC_ADDR_00] = 16, 316 [LOWPAN_IPHC_ADDR_01] = 8, 317 [LOWPAN_IPHC_ADDR_02] = 2, 318 [LOWPAN_IPHC_ADDR_03] = 0, 319 }; 320 return addr_sizes[addr_mode]; 321 } 322 323 static inline u8 lowpan_next_hdr_size(const u8 h_enc, u16 *uncomp_header) 324 { 325 u8 ret = 1; 326 327 if ((h_enc & LOWPAN_NHC_UDP_MASK) == LOWPAN_NHC_UDP_ID) { 328 *uncomp_header += sizeof(struct udphdr); 329 330 switch (h_enc & LOWPAN_NHC_UDP_CS_P_11) { 331 case LOWPAN_NHC_UDP_CS_P_00: 332 ret += 4; 333 break; 334 case LOWPAN_NHC_UDP_CS_P_01: 335 case LOWPAN_NHC_UDP_CS_P_10: 336 ret += 3; 337 break; 338 case LOWPAN_NHC_UDP_CS_P_11: 339 ret++; 340 break; 341 default: 342 break; 343 } 344 345 if (!(h_enc & LOWPAN_NHC_UDP_CS_C)) 346 ret += 2; 347 } 348 349 return ret; 350 } 351 352 /** 353 * lowpan_uncompress_size - returns skb->len size with uncompressed header 354 * @skb: sk_buff with 6lowpan header inside 355 * @datagram_offset: optional to get the datagram_offset value 356 * 357 * Returns the skb->len with uncompressed header 358 */ 359 static inline u16 360 lowpan_uncompress_size(const struct sk_buff *skb, u16 *dgram_offset) 361 { 362 u16 ret = 2, uncomp_header = sizeof(struct ipv6hdr); 363 u8 iphc0, iphc1, h_enc; 364 365 iphc0 = skb_network_header(skb)[0]; 366 iphc1 = skb_network_header(skb)[1]; 367 368 switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) { 369 case 0: 370 ret += 4; 371 break; 372 case 1: 373 ret += 3; 374 break; 375 case 2: 376 ret++; 377 break; 378 default: 379 break; 380 } 381 382 if (!(iphc0 & LOWPAN_IPHC_NH_C)) 383 ret++; 384 385 if (!(iphc0 & 0x03)) 386 ret++; 387 388 ret += lowpan_addr_mode_size((iphc1 & LOWPAN_IPHC_SAM) >> 389 LOWPAN_IPHC_SAM_BIT); 390 391 if (iphc1 & LOWPAN_IPHC_M) { 392 switch ((iphc1 & LOWPAN_IPHC_DAM_11) >> 393 LOWPAN_IPHC_DAM_BIT) { 394 case LOWPAN_IPHC_DAM_00: 395 ret += 16; 396 break; 397 case LOWPAN_IPHC_DAM_01: 398 ret += 6; 399 break; 400 case LOWPAN_IPHC_DAM_10: 401 ret += 4; 402 break; 403 case LOWPAN_IPHC_DAM_11: 404 ret++; 405 break; 406 default: 407 break; 408 } 409 } else { 410 ret += lowpan_addr_mode_size((iphc1 & LOWPAN_IPHC_DAM_11) >> 411 LOWPAN_IPHC_DAM_BIT); 412 } 413 414 if (iphc0 & LOWPAN_IPHC_NH_C) { 415 h_enc = skb_network_header(skb)[ret]; 416 ret += lowpan_next_hdr_size(h_enc, &uncomp_header); 417 } 418 419 if (dgram_offset) 420 *dgram_offset = uncomp_header; 421 422 return skb->len + uncomp_header - ret; 423 } 424 425 typedef int (*skb_delivery_cb)(struct sk_buff *skb, struct net_device *dev); 426 427 int lowpan_process_data(struct sk_buff *skb, struct net_device *dev, 428 const u8 *saddr, const u8 saddr_type, const u8 saddr_len, 429 const u8 *daddr, const u8 daddr_type, const u8 daddr_len, 430 u8 iphc0, u8 iphc1, skb_delivery_cb skb_deliver); 431 int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev, 432 unsigned short type, const void *_daddr, 433 const void *_saddr, unsigned int len); 434 435 #endif /* __6LOWPAN_H__ */ 436