1 /* Copyright 2011, Siemens AG 2 * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com> 3 */ 4 5 /* Based on patches from Jon Smirl <jonsmirl@gmail.com> 6 * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 10 * as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 */ 17 18 /* Jon's code is based on 6lowpan implementation for Contiki which is: 19 * Copyright (c) 2008, Swedish Institute of Computer Science. 20 * All rights reserved. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the above copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. Neither the name of the Institute nor the names of its contributors 31 * may be used to endorse or promote products derived from this software 32 * without specific prior written permission. 33 * 34 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 35 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 36 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 37 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 38 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 39 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 40 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 41 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 42 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 43 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 44 * SUCH DAMAGE. 45 */ 46 47 #include <linux/module.h> 48 #include <linux/netdevice.h> 49 #include <linux/ieee802154.h> 50 51 #include <net/ipv6.h> 52 53 #include "6lowpan_i.h" 54 55 static int open_count; 56 57 static struct header_ops lowpan_header_ops = { 58 .create = lowpan_header_create, 59 }; 60 61 static struct lock_class_key lowpan_tx_busylock; 62 static struct lock_class_key lowpan_netdev_xmit_lock_key; 63 64 static void lowpan_set_lockdep_class_one(struct net_device *dev, 65 struct netdev_queue *txq, 66 void *_unused) 67 { 68 lockdep_set_class(&txq->_xmit_lock, 69 &lowpan_netdev_xmit_lock_key); 70 } 71 72 static int lowpan_dev_init(struct net_device *dev) 73 { 74 netdev_for_each_tx_queue(dev, lowpan_set_lockdep_class_one, NULL); 75 dev->qdisc_tx_busylock = &lowpan_tx_busylock; 76 return 0; 77 } 78 79 static const struct net_device_ops lowpan_netdev_ops = { 80 .ndo_init = lowpan_dev_init, 81 .ndo_start_xmit = lowpan_xmit, 82 }; 83 84 static void lowpan_setup(struct net_device *dev) 85 { 86 dev->addr_len = IEEE802154_ADDR_LEN; 87 memset(dev->broadcast, 0xff, IEEE802154_ADDR_LEN); 88 dev->type = ARPHRD_6LOWPAN; 89 /* Frame Control + Sequence Number + Address fields + Security Header */ 90 dev->hard_header_len = 2 + 1 + 20 + 14; 91 dev->needed_tailroom = 2; /* FCS */ 92 dev->mtu = IPV6_MIN_MTU; 93 dev->priv_flags |= IFF_NO_QUEUE; 94 dev->flags = IFF_BROADCAST | IFF_MULTICAST; 95 dev->watchdog_timeo = 0; 96 97 dev->netdev_ops = &lowpan_netdev_ops; 98 dev->header_ops = &lowpan_header_ops; 99 dev->destructor = free_netdev; 100 dev->features |= NETIF_F_NETNS_LOCAL; 101 } 102 103 static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[]) 104 { 105 if (tb[IFLA_ADDRESS]) { 106 if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN) 107 return -EINVAL; 108 } 109 return 0; 110 } 111 112 static int lowpan_newlink(struct net *src_net, struct net_device *dev, 113 struct nlattr *tb[], struct nlattr *data[]) 114 { 115 struct net_device *real_dev; 116 int ret; 117 118 ASSERT_RTNL(); 119 120 pr_debug("adding new link\n"); 121 122 if (!tb[IFLA_LINK] || 123 !net_eq(dev_net(dev), &init_net)) 124 return -EINVAL; 125 /* find and hold real wpan device */ 126 real_dev = dev_get_by_index(dev_net(dev), nla_get_u32(tb[IFLA_LINK])); 127 if (!real_dev) 128 return -ENODEV; 129 if (real_dev->type != ARPHRD_IEEE802154) { 130 dev_put(real_dev); 131 return -EINVAL; 132 } 133 134 if (real_dev->ieee802154_ptr->lowpan_dev) { 135 dev_put(real_dev); 136 return -EBUSY; 137 } 138 139 lowpan_dev_info(dev)->real_dev = real_dev; 140 /* Set the lowpan hardware address to the wpan hardware address. */ 141 memcpy(dev->dev_addr, real_dev->dev_addr, IEEE802154_ADDR_LEN); 142 143 lowpan_netdev_setup(dev, LOWPAN_LLTYPE_IEEE802154); 144 145 ret = register_netdevice(dev); 146 if (ret < 0) { 147 dev_put(real_dev); 148 return ret; 149 } 150 151 real_dev->ieee802154_ptr->lowpan_dev = dev; 152 if (!open_count) 153 lowpan_rx_init(); 154 155 open_count++; 156 157 return 0; 158 } 159 160 static void lowpan_dellink(struct net_device *dev, struct list_head *head) 161 { 162 struct lowpan_dev_info *lowpan_dev = lowpan_dev_info(dev); 163 struct net_device *real_dev = lowpan_dev->real_dev; 164 165 ASSERT_RTNL(); 166 167 open_count--; 168 169 if (!open_count) 170 lowpan_rx_exit(); 171 172 real_dev->ieee802154_ptr->lowpan_dev = NULL; 173 unregister_netdevice(dev); 174 dev_put(real_dev); 175 } 176 177 static struct rtnl_link_ops lowpan_link_ops __read_mostly = { 178 .kind = "lowpan", 179 .priv_size = LOWPAN_PRIV_SIZE(sizeof(struct lowpan_dev_info)), 180 .setup = lowpan_setup, 181 .newlink = lowpan_newlink, 182 .dellink = lowpan_dellink, 183 .validate = lowpan_validate, 184 }; 185 186 static inline int __init lowpan_netlink_init(void) 187 { 188 return rtnl_link_register(&lowpan_link_ops); 189 } 190 191 static inline void lowpan_netlink_fini(void) 192 { 193 rtnl_link_unregister(&lowpan_link_ops); 194 } 195 196 static int lowpan_device_event(struct notifier_block *unused, 197 unsigned long event, void *ptr) 198 { 199 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 200 201 if (dev->type != ARPHRD_IEEE802154) 202 goto out; 203 204 switch (event) { 205 case NETDEV_UNREGISTER: 206 /* Check if wpan interface is unregistered that we 207 * also delete possible lowpan interfaces which belongs 208 * to the wpan interface. 209 */ 210 if (dev->ieee802154_ptr && dev->ieee802154_ptr->lowpan_dev) 211 lowpan_dellink(dev->ieee802154_ptr->lowpan_dev, NULL); 212 break; 213 default: 214 break; 215 } 216 217 out: 218 return NOTIFY_DONE; 219 } 220 221 static struct notifier_block lowpan_dev_notifier = { 222 .notifier_call = lowpan_device_event, 223 }; 224 225 static int __init lowpan_init_module(void) 226 { 227 int err = 0; 228 229 err = lowpan_net_frag_init(); 230 if (err < 0) 231 goto out; 232 233 err = lowpan_netlink_init(); 234 if (err < 0) 235 goto out_frag; 236 237 err = register_netdevice_notifier(&lowpan_dev_notifier); 238 if (err < 0) 239 goto out_pack; 240 241 return 0; 242 243 out_pack: 244 lowpan_netlink_fini(); 245 out_frag: 246 lowpan_net_frag_exit(); 247 out: 248 return err; 249 } 250 251 static void __exit lowpan_cleanup_module(void) 252 { 253 lowpan_netlink_fini(); 254 255 lowpan_net_frag_exit(); 256 257 unregister_netdevice_notifier(&lowpan_dev_notifier); 258 } 259 260 module_init(lowpan_init_module); 261 module_exit(lowpan_cleanup_module); 262 MODULE_LICENSE("GPL"); 263 MODULE_ALIAS_RTNL_LINK("lowpan"); 264