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