include/net/6lowpan.h

   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_IPHC            0x60 /* 011xxxxx = ... */
 131 #define LOWPAN_DISPATCH_IPHC_MASK       0xe0
 132
 133 static inline bool lowpan_is_ipv6(u8 dispatch)
 134 {
 135         return dispatch == LOWPAN_DISPATCH_IPV6;
 136 }
 137
 138 static inline bool lowpan_is_iphc(u8 dispatch)
 139 {
 140         return (dispatch & LOWPAN_DISPATCH_IPHC_MASK) == LOWPAN_DISPATCH_IPHC;
 141 }
 142
 143 #define LOWPAN_FRAG_TIMEOUT     (HZ * 60)       /* time-out 60 sec */
 144
 145 #define LOWPAN_FRAG1_HEAD_SIZE  0x4
 146 #define LOWPAN_FRAGN_HEAD_SIZE  0x5
 147
 148 /*
 149  * Values of fields within the IPHC encoding first byte
 150  * (C stands for compressed and I for inline)
 151  */
 152 #define LOWPAN_IPHC_TF          0x18
 153
 154 #define LOWPAN_IPHC_FL_C        0x10
 155 #define LOWPAN_IPHC_TC_C        0x08
 156 #define LOWPAN_IPHC_NH_C        0x04
 157 #define LOWPAN_IPHC_TTL_1       0x01
 158 #define LOWPAN_IPHC_TTL_64      0x02
 159 #define LOWPAN_IPHC_TTL_255     0x03
 160 #define LOWPAN_IPHC_TTL_I       0x00
 161
 162
 163 /* Values of fields within the IPHC encoding second byte */
 164 #define LOWPAN_IPHC_CID         0x80
 165
 166 #define LOWPAN_IPHC_ADDR_00     0x00
 167 #define LOWPAN_IPHC_ADDR_01     0x01
 168 #define LOWPAN_IPHC_ADDR_02     0x02
 169 #define LOWPAN_IPHC_ADDR_03     0x03
 170
 171 #define LOWPAN_IPHC_SAC         0x40
 172 #define LOWPAN_IPHC_SAM         0x30
 173
 174 #define LOWPAN_IPHC_SAM_BIT     4
 175
 176 #define LOWPAN_IPHC_M           0x08
 177 #define LOWPAN_IPHC_DAC         0x04
 178 #define LOWPAN_IPHC_DAM_00      0x00
 179 #define LOWPAN_IPHC_DAM_01      0x01
 180 #define LOWPAN_IPHC_DAM_10      0x02
 181 #define LOWPAN_IPHC_DAM_11      0x03
 182
 183 #define LOWPAN_IPHC_DAM_BIT     0
 184 /*
 185  * LOWPAN_UDP encoding (works together with IPHC)
 186  */
 187 #define LOWPAN_NHC_UDP_MASK             0xF8
 188 #define LOWPAN_NHC_UDP_ID               0xF0
 189 #define LOWPAN_NHC_UDP_CHECKSUMC        0x04
 190 #define LOWPAN_NHC_UDP_CHECKSUMI        0x00
 191
 192 #define LOWPAN_NHC_UDP_4BIT_PORT        0xF0B0
 193 #define LOWPAN_NHC_UDP_4BIT_MASK        0xFFF0
 194 #define LOWPAN_NHC_UDP_8BIT_PORT        0xF000
 195 #define LOWPAN_NHC_UDP_8BIT_MASK        0xFF00
 196
 197 /* values for port compression, _with checksum_ ie bit 5 set to 0 */
 198 #define LOWPAN_NHC_UDP_CS_P_00  0xF0 /* all inline */
 199 #define LOWPAN_NHC_UDP_CS_P_01  0xF1 /* source 16bit inline,
 200                                         dest = 0xF0 + 8 bit inline */
 201 #define LOWPAN_NHC_UDP_CS_P_10  0xF2 /* source = 0xF0 + 8bit inline,
 202                                         dest = 16 bit inline */
 203 #define LOWPAN_NHC_UDP_CS_P_11  0xF3 /* source & dest = 0xF0B + 4bit inline */
 204 #define LOWPAN_NHC_UDP_CS_C     0x04 /* checksum elided */
 205
 206 #define LOWPAN_PRIV_SIZE(llpriv_size)   \
 207         (sizeof(struct lowpan_priv) + llpriv_size)
 208
 209 enum lowpan_lltypes {
 210         LOWPAN_LLTYPE_BTLE,
 211         LOWPAN_LLTYPE_IEEE802154,
 212 };
 213
 214 struct lowpan_priv {
 215         enum lowpan_lltypes lltype;
 216
 217         /* must be last */
 218         u8 priv[0] __aligned(sizeof(void *));
 219 };
 220
 221 static inline
 222 struct lowpan_priv *lowpan_priv(const struct net_device *dev)
 223 {
 224         return netdev_priv(dev);
 225 }
 226
 227 struct lowpan_802154_cb {
 228         u16 d_tag;
 229         unsigned int d_size;
 230         u8 d_offset;
 231 };
 232
 233 static inline
 234 struct lowpan_802154_cb *lowpan_802154_cb(const struct sk_buff *skb)
 235 {
 236         BUILD_BUG_ON(sizeof(struct lowpan_802154_cb) > sizeof(skb->cb));
 237         return (struct lowpan_802154_cb *)skb->cb;
 238 }
 239
 240 #ifdef DEBUG
 241 /* print data in line */
 242 static inline void raw_dump_inline(const char *caller, char *msg,
 243                                    unsigned char *buf, int len)
 244 {
 245         if (msg)
 246                 pr_debug("%s():%s: ", caller, msg);
 247
 248         print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, buf, len, false);
 249 }
 250
 251 /* print data in a table format:
 252  *
 253  * addr: xx xx xx xx xx xx
 254  * addr: xx xx xx xx xx xx
 255  * ...
 256  */
 257 static inline void raw_dump_table(const char *caller, char *msg,
 258                                   unsigned char *buf, int len)
 259 {
 260         if (msg)
 261                 pr_debug("%s():%s:\n", caller, msg);
 262
 263         print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET, 16, 1, buf, len, false);
 264 }
 265 #else
 266 static inline void raw_dump_table(const char *caller, char *msg,
 267                                   unsigned char *buf, int len) { }
 268 static inline void raw_dump_inline(const char *caller, char *msg,
 269                                    unsigned char *buf, int len) { }
 270 #endif
 271
 272 static inline int lowpan_fetch_skb_u8(struct sk_buff *skb, u8 *val)
 273 {
 274         if (unlikely(!pskb_may_pull(skb, 1)))
 275                 return -EINVAL;
 276
 277         *val = skb->data[0];
 278         skb_pull(skb, 1);
 279
 280         return 0;
 281 }
 282
 283 static inline bool lowpan_fetch_skb(struct sk_buff *skb,
 284                 void *data, const unsigned int len)
 285 {
 286         if (unlikely(!pskb_may_pull(skb, len)))
 287                 return true;
 288
 289         skb_copy_from_linear_data(skb, data, len);
 290         skb_pull(skb, len);
 291
 292         return false;
 293 }
 294
 295 static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data,
 296                                        const size_t len)
 297 {
 298         memcpy(*hc_ptr, data, len);
 299         *hc_ptr += len;
 300 }
 301
 302 void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype);
 303
 304 int
 305 lowpan_header_decompress(struct sk_buff *skb, struct net_device *dev,
 306                          const u8 *saddr, const u8 saddr_type,
 307                          const u8 saddr_len, const u8 *daddr,
 308                          const u8 daddr_type, const u8 daddr_len,
 309                          u8 iphc0, u8 iphc1);
 310 int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev,
 311                         unsigned short type, const void *_daddr,
 312                         const void *_saddr, unsigned int len);
 313
 314 #endif /* __6LOWPAN_H__ */