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 <linux/debugfs.h> 57 58 #include <net/ipv6.h> 59 #include <net/net_namespace.h> 60 61 /* special link-layer handling */ 62 #include <net/mac802154.h> 63 64 #define EUI64_ADDR_LEN 8 65 66 #define LOWPAN_NHC_MAX_ID_LEN 1 67 /* Maximum next header compression length which we currently support inclusive 68 * possible inline data. 69 */ 70 #define LOWPAN_NHC_MAX_HDR_LEN (sizeof(struct udphdr)) 71 /* Max IPHC Header len without IPv6 hdr specific inline data. 72 * Useful for getting the "extra" bytes we need at worst case compression. 73 * 74 * LOWPAN_IPHC + CID + LOWPAN_NHC_MAX_ID_LEN 75 */ 76 #define LOWPAN_IPHC_MAX_HEADER_LEN (2 + 1 + LOWPAN_NHC_MAX_ID_LEN) 77 /* Maximum worst case IPHC header buffer size */ 78 #define LOWPAN_IPHC_MAX_HC_BUF_LEN (sizeof(struct ipv6hdr) + \ 79 LOWPAN_IPHC_MAX_HEADER_LEN + \ 80 LOWPAN_NHC_MAX_HDR_LEN) 81 /* SCI/DCI is 4 bit width, so we have maximum 16 entries */ 82 #define LOWPAN_IPHC_CTX_TABLE_SIZE (1 << 4) 83 84 #define LOWPAN_DISPATCH_IPV6 0x41 /* 01000001 = 65 */ 85 #define LOWPAN_DISPATCH_IPHC 0x60 /* 011xxxxx = ... */ 86 #define LOWPAN_DISPATCH_IPHC_MASK 0xe0 87 88 static inline bool lowpan_is_ipv6(u8 dispatch) 89 { 90 return dispatch == LOWPAN_DISPATCH_IPV6; 91 } 92 93 static inline bool lowpan_is_iphc(u8 dispatch) 94 { 95 return (dispatch & LOWPAN_DISPATCH_IPHC_MASK) == LOWPAN_DISPATCH_IPHC; 96 } 97 98 #define LOWPAN_PRIV_SIZE(llpriv_size) \ 99 (sizeof(struct lowpan_dev) + llpriv_size) 100 101 enum lowpan_lltypes { 102 LOWPAN_LLTYPE_BTLE, 103 LOWPAN_LLTYPE_IEEE802154, 104 }; 105 106 enum lowpan_iphc_ctx_flags { 107 LOWPAN_IPHC_CTX_FLAG_ACTIVE, 108 LOWPAN_IPHC_CTX_FLAG_COMPRESSION, 109 }; 110 111 struct lowpan_iphc_ctx { 112 u8 id; 113 struct in6_addr pfx; 114 u8 plen; 115 unsigned long flags; 116 }; 117 118 struct lowpan_iphc_ctx_table { 119 spinlock_t lock; 120 const struct lowpan_iphc_ctx_ops *ops; 121 struct lowpan_iphc_ctx table[LOWPAN_IPHC_CTX_TABLE_SIZE]; 122 }; 123 124 static inline bool lowpan_iphc_ctx_is_active(const struct lowpan_iphc_ctx *ctx) 125 { 126 return test_bit(LOWPAN_IPHC_CTX_FLAG_ACTIVE, &ctx->flags); 127 } 128 129 static inline bool 130 lowpan_iphc_ctx_is_compression(const struct lowpan_iphc_ctx *ctx) 131 { 132 return test_bit(LOWPAN_IPHC_CTX_FLAG_COMPRESSION, &ctx->flags); 133 } 134 135 struct lowpan_dev { 136 enum lowpan_lltypes lltype; 137 struct dentry *iface_debugfs; 138 struct lowpan_iphc_ctx_table ctx; 139 140 /* must be last */ 141 u8 priv[0] __aligned(sizeof(void *)); 142 }; 143 144 static inline 145 struct lowpan_dev *lowpan_dev(const struct net_device *dev) 146 { 147 return netdev_priv(dev); 148 } 149 150 /* private device info */ 151 struct lowpan_802154_dev { 152 struct net_device *wdev; /* wpan device ptr */ 153 u16 fragment_tag; 154 }; 155 156 static inline struct 157 lowpan_802154_dev *lowpan_802154_dev(const struct net_device *dev) 158 { 159 return (struct lowpan_802154_dev *)lowpan_dev(dev)->priv; 160 } 161 162 struct lowpan_802154_cb { 163 u16 d_tag; 164 unsigned int d_size; 165 u8 d_offset; 166 }; 167 168 static inline 169 struct lowpan_802154_cb *lowpan_802154_cb(const struct sk_buff *skb) 170 { 171 BUILD_BUG_ON(sizeof(struct lowpan_802154_cb) > sizeof(skb->cb)); 172 return (struct lowpan_802154_cb *)skb->cb; 173 } 174 175 static inline void lowpan_iphc_uncompress_eui64_lladdr(struct in6_addr *ipaddr, 176 const void *lladdr) 177 { 178 /* fe:80::XXXX:XXXX:XXXX:XXXX 179 * \_________________/ 180 * hwaddr 181 */ 182 ipaddr->s6_addr[0] = 0xFE; 183 ipaddr->s6_addr[1] = 0x80; 184 memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN); 185 /* second bit-flip (Universe/Local) 186 * is done according RFC2464 187 */ 188 ipaddr->s6_addr[8] ^= 0x02; 189 } 190 191 #ifdef DEBUG 192 /* print data in line */ 193 static inline void raw_dump_inline(const char *caller, char *msg, 194 const unsigned char *buf, int len) 195 { 196 if (msg) 197 pr_debug("%s():%s: ", caller, msg); 198 199 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, buf, len, false); 200 } 201 202 /* print data in a table format: 203 * 204 * addr: xx xx xx xx xx xx 205 * addr: xx xx xx xx xx xx 206 * ... 207 */ 208 static inline void raw_dump_table(const char *caller, char *msg, 209 const unsigned char *buf, int len) 210 { 211 if (msg) 212 pr_debug("%s():%s:\n", caller, msg); 213 214 print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET, 16, 1, buf, len, false); 215 } 216 #else 217 static inline void raw_dump_table(const char *caller, char *msg, 218 const unsigned char *buf, int len) { } 219 static inline void raw_dump_inline(const char *caller, char *msg, 220 const unsigned char *buf, int len) { } 221 #endif 222 223 /** 224 * lowpan_fetch_skb - getting inline data from 6LoWPAN header 225 * 226 * This function will pull data from sk buffer and put it into data to 227 * remove the 6LoWPAN inline data. This function returns true if the 228 * sk buffer is too small to pull the amount of data which is specified 229 * by len. 230 * 231 * @skb: the buffer where the inline data should be pulled from. 232 * @data: destination buffer for the inline data. 233 * @len: amount of data which should be pulled in bytes. 234 */ 235 static inline bool lowpan_fetch_skb(struct sk_buff *skb, void *data, 236 unsigned int len) 237 { 238 if (unlikely(!pskb_may_pull(skb, len))) 239 return true; 240 241 skb_copy_from_linear_data(skb, data, len); 242 skb_pull(skb, len); 243 244 return false; 245 } 246 247 static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data, 248 const size_t len) 249 { 250 memcpy(*hc_ptr, data, len); 251 *hc_ptr += len; 252 } 253 254 int lowpan_register_netdevice(struct net_device *dev, 255 enum lowpan_lltypes lltype); 256 int lowpan_register_netdev(struct net_device *dev, 257 enum lowpan_lltypes lltype); 258 void lowpan_unregister_netdevice(struct net_device *dev); 259 void lowpan_unregister_netdev(struct net_device *dev); 260 261 /** 262 * lowpan_header_decompress - replace 6LoWPAN header with IPv6 header 263 * 264 * This function replaces the IPHC 6LoWPAN header which should be pointed at 265 * skb->data and skb_network_header, with the IPv6 header. 266 * It would be nice that the caller have the necessary headroom of IPv6 header 267 * and greatest Transport layer header, this would reduce the overhead for 268 * reallocate headroom. 269 * 270 * @skb: the buffer which should be manipulate. 271 * @dev: the lowpan net device pointer. 272 * @daddr: destination lladdr of mac header which is used for compression 273 * methods. 274 * @saddr: source lladdr of mac header which is used for compression 275 * methods. 276 */ 277 int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev, 278 const void *daddr, const void *saddr); 279 280 /** 281 * lowpan_header_compress - replace IPv6 header with 6LoWPAN header 282 * 283 * This function replaces the IPv6 header which should be pointed at 284 * skb->data and skb_network_header, with the IPHC 6LoWPAN header. 285 * The caller need to be sure that the sk buffer is not shared and at have 286 * at least a headroom which is smaller or equal LOWPAN_IPHC_MAX_HEADER_LEN, 287 * which is the IPHC "more bytes than IPv6 header" at worst case. 288 * 289 * @skb: the buffer which should be manipulate. 290 * @dev: the lowpan net device pointer. 291 * @daddr: destination lladdr of mac header which is used for compression 292 * methods. 293 * @saddr: source lladdr of mac header which is used for compression 294 * methods. 295 */ 296 int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev, 297 const void *daddr, const void *saddr); 298 299 #endif /* __6LOWPAN_H__ */ 300