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 EUI64_ADDR_LEN 8 60 61 #define LOWPAN_NHC_MAX_ID_LEN 1 62 /* Maximum next header compression length which we currently support inclusive 63 * possible inline data. 64 */ 65 #define LOWPAN_NHC_MAX_HDR_LEN (sizeof(struct udphdr)) 66 /* Max IPHC Header len without IPv6 hdr specific inline data. 67 * Useful for getting the "extra" bytes we need at worst case compression. 68 * 69 * LOWPAN_IPHC + CID + LOWPAN_NHC_MAX_ID_LEN 70 */ 71 #define LOWPAN_IPHC_MAX_HEADER_LEN (2 + 1 + LOWPAN_NHC_MAX_ID_LEN) 72 /* Maximum worst case IPHC header buffer size */ 73 #define LOWPAN_IPHC_MAX_HC_BUF_LEN (sizeof(struct ipv6hdr) + \ 74 LOWPAN_IPHC_MAX_HEADER_LEN + \ 75 LOWPAN_NHC_MAX_HDR_LEN) 76 77 #define LOWPAN_DISPATCH_IPV6 0x41 /* 01000001 = 65 */ 78 #define LOWPAN_DISPATCH_IPHC 0x60 /* 011xxxxx = ... */ 79 #define LOWPAN_DISPATCH_IPHC_MASK 0xe0 80 81 static inline bool lowpan_is_ipv6(u8 dispatch) 82 { 83 return dispatch == LOWPAN_DISPATCH_IPV6; 84 } 85 86 static inline bool lowpan_is_iphc(u8 dispatch) 87 { 88 return (dispatch & LOWPAN_DISPATCH_IPHC_MASK) == LOWPAN_DISPATCH_IPHC; 89 } 90 91 #define LOWPAN_PRIV_SIZE(llpriv_size) \ 92 (sizeof(struct lowpan_priv) + llpriv_size) 93 94 enum lowpan_lltypes { 95 LOWPAN_LLTYPE_BTLE, 96 LOWPAN_LLTYPE_IEEE802154, 97 }; 98 99 struct lowpan_priv { 100 enum lowpan_lltypes lltype; 101 102 /* must be last */ 103 u8 priv[0] __aligned(sizeof(void *)); 104 }; 105 106 static inline 107 struct lowpan_priv *lowpan_priv(const struct net_device *dev) 108 { 109 return netdev_priv(dev); 110 } 111 112 struct lowpan_802154_cb { 113 u16 d_tag; 114 unsigned int d_size; 115 u8 d_offset; 116 }; 117 118 static inline 119 struct lowpan_802154_cb *lowpan_802154_cb(const struct sk_buff *skb) 120 { 121 BUILD_BUG_ON(sizeof(struct lowpan_802154_cb) > sizeof(skb->cb)); 122 return (struct lowpan_802154_cb *)skb->cb; 123 } 124 125 #ifdef DEBUG 126 /* print data in line */ 127 static inline void raw_dump_inline(const char *caller, char *msg, 128 const unsigned char *buf, int len) 129 { 130 if (msg) 131 pr_debug("%s():%s: ", caller, msg); 132 133 print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1, buf, len, false); 134 } 135 136 /* print data in a table format: 137 * 138 * addr: xx xx xx xx xx xx 139 * addr: xx xx xx xx xx xx 140 * ... 141 */ 142 static inline void raw_dump_table(const char *caller, char *msg, 143 const unsigned char *buf, int len) 144 { 145 if (msg) 146 pr_debug("%s():%s:\n", caller, msg); 147 148 print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET, 16, 1, buf, len, false); 149 } 150 #else 151 static inline void raw_dump_table(const char *caller, char *msg, 152 const unsigned char *buf, int len) { } 153 static inline void raw_dump_inline(const char *caller, char *msg, 154 const unsigned char *buf, int len) { } 155 #endif 156 157 /** 158 * lowpan_fetch_skb - getting inline data from 6LoWPAN header 159 * 160 * This function will pull data from sk buffer and put it into data to 161 * remove the 6LoWPAN inline data. This function returns true if the 162 * sk buffer is too small to pull the amount of data which is specified 163 * by len. 164 * 165 * @skb: the buffer where the inline data should be pulled from. 166 * @data: destination buffer for the inline data. 167 * @len: amount of data which should be pulled in bytes. 168 */ 169 static inline bool lowpan_fetch_skb(struct sk_buff *skb, void *data, 170 unsigned int len) 171 { 172 if (unlikely(!pskb_may_pull(skb, len))) 173 return true; 174 175 skb_copy_from_linear_data(skb, data, len); 176 skb_pull(skb, len); 177 178 return false; 179 } 180 181 static inline void lowpan_push_hc_data(u8 **hc_ptr, const void *data, 182 const size_t len) 183 { 184 memcpy(*hc_ptr, data, len); 185 *hc_ptr += len; 186 } 187 188 void lowpan_netdev_setup(struct net_device *dev, enum lowpan_lltypes lltype); 189 190 /** 191 * lowpan_header_decompress - replace 6LoWPAN header with IPv6 header 192 * 193 * This function replaces the IPHC 6LoWPAN header which should be pointed at 194 * skb->data and skb_network_header, with the IPv6 header. 195 * It would be nice that the caller have the necessary headroom of IPv6 header 196 * and greatest Transport layer header, this would reduce the overhead for 197 * reallocate headroom. 198 * 199 * @skb: the buffer which should be manipulate. 200 * @dev: the lowpan net device pointer. 201 * @daddr: destination lladdr of mac header which is used for compression 202 * methods. 203 * @saddr: source lladdr of mac header which is used for compression 204 * methods. 205 */ 206 int lowpan_header_decompress(struct sk_buff *skb, const struct net_device *dev, 207 const void *daddr, const void *saddr); 208 209 /** 210 * lowpan_header_compress - replace IPv6 header with 6LoWPAN header 211 * 212 * This function replaces the IPv6 header which should be pointed at 213 * skb->data and skb_network_header, with the IPHC 6LoWPAN header. 214 * The caller need to be sure that the sk buffer is not shared and at have 215 * at least a headroom which is smaller or equal LOWPAN_IPHC_MAX_HEADER_LEN, 216 * which is the IPHC "more bytes than IPv6 header" at worst case. 217 * 218 * @skb: the buffer which should be manipulate. 219 * @dev: the lowpan net device pointer. 220 * @daddr: destination lladdr of mac header which is used for compression 221 * methods. 222 * @saddr: source lladdr of mac header which is used for compression 223 * methods. 224 */ 225 int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev, 226 const void *daddr, const void *saddr); 227 228 #endif /* __6LOWPAN_H__ */ 229