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