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 struct header_ops lowpan_header_ops = { 56 .create = lowpan_header_create, 57 }; 58 59 static struct lock_class_key lowpan_tx_busylock; 60 static struct lock_class_key lowpan_netdev_xmit_lock_key; 61 62 static void lowpan_set_lockdep_class_one(struct net_device *dev, 63 struct netdev_queue *txq, 64 void *_unused) 65 { 66 lockdep_set_class(&txq->_xmit_lock, 67 &lowpan_netdev_xmit_lock_key); 68 } 69 70 static int lowpan_dev_init(struct net_device *dev) 71 { 72 netdev_for_each_tx_queue(dev, lowpan_set_lockdep_class_one, NULL); 73 dev->qdisc_tx_busylock = &lowpan_tx_busylock; 74 return 0; 75 } 76 77 static const struct net_device_ops lowpan_netdev_ops = { 78 .ndo_init = lowpan_dev_init, 79 .ndo_start_xmit = lowpan_xmit, 80 }; 81 82 static void lowpan_setup(struct net_device *dev) 83 { 84 dev->addr_len = IEEE802154_ADDR_LEN; 85 memset(dev->broadcast, 0xff, IEEE802154_ADDR_LEN); 86 dev->type = ARPHRD_6LOWPAN; 87 /* Frame Control + Sequence Number + Address fields + Security Header */ 88 dev->hard_header_len = 2 + 1 + 20 + 14; 89 dev->needed_tailroom = 2; /* FCS */ 90 dev->mtu = IPV6_MIN_MTU; 91 dev->tx_queue_len = 0; 92 dev->flags = IFF_BROADCAST | IFF_MULTICAST; 93 dev->watchdog_timeo = 0; 94 95 dev->netdev_ops = &lowpan_netdev_ops; 96 dev->header_ops = &lowpan_header_ops; 97 dev->destructor = free_netdev; 98 dev->features |= NETIF_F_NETNS_LOCAL; 99 } 100 101 static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[]) 102 { 103 if (tb[IFLA_ADDRESS]) { 104 if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN) 105 return -EINVAL; 106 } 107 return 0; 108 } 109 110 static int lowpan_newlink(struct net *src_net, struct net_device *dev, 111 struct nlattr *tb[], struct nlattr *data[]) 112 { 113 struct net_device *real_dev; 114 int ret; 115 116 ASSERT_RTNL(); 117 118 pr_debug("adding new link\n"); 119 120 if (!tb[IFLA_LINK] || 121 !net_eq(dev_net(dev), &init_net)) 122 return -EINVAL; 123 /* find and hold real wpan device */ 124 real_dev = dev_get_by_index(dev_net(dev), nla_get_u32(tb[IFLA_LINK])); 125 if (!real_dev) 126 return -ENODEV; 127 if (real_dev->type != ARPHRD_IEEE802154) { 128 dev_put(real_dev); 129 return -EINVAL; 130 } 131 132 if (real_dev->ieee802154_ptr->lowpan_dev) { 133 dev_put(real_dev); 134 return -EBUSY; 135 } 136 137 lowpan_dev_info(dev)->real_dev = real_dev; 138 /* Set the lowpan hardware address to the wpan hardware address. */ 139 memcpy(dev->dev_addr, real_dev->dev_addr, IEEE802154_ADDR_LEN); 140 141 lowpan_netdev_setup(dev, LOWPAN_LLTYPE_IEEE802154); 142 143 ret = register_netdevice(dev); 144 if (ret >= 0) { 145 real_dev->ieee802154_ptr->lowpan_dev = dev; 146 lowpan_rx_init(); 147 } 148 149 return ret; 150 } 151 152 static void lowpan_dellink(struct net_device *dev, struct list_head *head) 153 { 154 struct lowpan_dev_info *lowpan_dev = lowpan_dev_info(dev); 155 struct net_device *real_dev = lowpan_dev->real_dev; 156 157 ASSERT_RTNL(); 158 159 lowpan_rx_exit(); 160 real_dev->ieee802154_ptr->lowpan_dev = NULL; 161 unregister_netdevice(dev); 162 dev_put(real_dev); 163 } 164 165 static struct rtnl_link_ops lowpan_link_ops __read_mostly = { 166 .kind = "lowpan", 167 .priv_size = LOWPAN_PRIV_SIZE(sizeof(struct lowpan_dev_info)), 168 .setup = lowpan_setup, 169 .newlink = lowpan_newlink, 170 .dellink = lowpan_dellink, 171 .validate = lowpan_validate, 172 }; 173 174 static inline int __init lowpan_netlink_init(void) 175 { 176 return rtnl_link_register(&lowpan_link_ops); 177 } 178 179 static inline void lowpan_netlink_fini(void) 180 { 181 rtnl_link_unregister(&lowpan_link_ops); 182 } 183 184 static int lowpan_device_event(struct notifier_block *unused, 185 unsigned long event, void *ptr) 186 { 187 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 188 189 if (dev->type != ARPHRD_IEEE802154) 190 goto out; 191 192 switch (event) { 193 case NETDEV_UNREGISTER: 194 /* Check if wpan interface is unregistered that we 195 * also delete possible lowpan interfaces which belongs 196 * to the wpan interface. 197 */ 198 if (dev->ieee802154_ptr && dev->ieee802154_ptr->lowpan_dev) 199 lowpan_dellink(dev->ieee802154_ptr->lowpan_dev, NULL); 200 break; 201 default: 202 break; 203 } 204 205 out: 206 return NOTIFY_DONE; 207 } 208 209 static struct notifier_block lowpan_dev_notifier = { 210 .notifier_call = lowpan_device_event, 211 }; 212 213 static int __init lowpan_init_module(void) 214 { 215 int err = 0; 216 217 err = lowpan_net_frag_init(); 218 if (err < 0) 219 goto out; 220 221 err = lowpan_netlink_init(); 222 if (err < 0) 223 goto out_frag; 224 225 err = register_netdevice_notifier(&lowpan_dev_notifier); 226 if (err < 0) 227 goto out_pack; 228 229 return 0; 230 231 out_pack: 232 lowpan_netlink_fini(); 233 out_frag: 234 lowpan_net_frag_exit(); 235 out: 236 return err; 237 } 238 239 static void __exit lowpan_cleanup_module(void) 240 { 241 lowpan_netlink_fini(); 242 243 lowpan_net_frag_exit(); 244 245 unregister_netdevice_notifier(&lowpan_dev_notifier); 246 } 247 248 module_init(lowpan_init_module); 249 module_exit(lowpan_cleanup_module); 250 MODULE_LICENSE("GPL"); 251 MODULE_ALIAS_RTNL_LINK("lowpan"); 252