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 *ldev, 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 *ldev) 73 { 74 netdev_for_each_tx_queue(ldev, lowpan_set_lockdep_class_one, NULL); 75 ldev->qdisc_tx_busylock = &lowpan_tx_busylock; 76 return 0; 77 } 78 79 static int lowpan_open(struct net_device *dev) 80 { 81 if (!open_count) 82 lowpan_rx_init(); 83 open_count++; 84 return 0; 85 } 86 87 static int lowpan_stop(struct net_device *dev) 88 { 89 open_count--; 90 if (!open_count) 91 lowpan_rx_exit(); 92 return 0; 93 } 94 95 static const struct net_device_ops lowpan_netdev_ops = { 96 .ndo_init = lowpan_dev_init, 97 .ndo_start_xmit = lowpan_xmit, 98 .ndo_open = lowpan_open, 99 .ndo_stop = lowpan_stop, 100 }; 101 102 static void lowpan_setup(struct net_device *ldev) 103 { 104 ldev->addr_len = IEEE802154_ADDR_LEN; 105 memset(ldev->broadcast, 0xff, IEEE802154_ADDR_LEN); 106 ldev->type = ARPHRD_6LOWPAN; 107 /* Frame Control + Sequence Number + Address fields + Security Header */ 108 ldev->hard_header_len = 2 + 1 + 20 + 14; 109 ldev->needed_tailroom = 2; /* FCS */ 110 ldev->mtu = IPV6_MIN_MTU; 111 ldev->priv_flags |= IFF_NO_QUEUE; 112 ldev->flags = IFF_BROADCAST | IFF_MULTICAST; 113 114 ldev->netdev_ops = &lowpan_netdev_ops; 115 ldev->header_ops = &lowpan_header_ops; 116 ldev->destructor = free_netdev; 117 ldev->features |= NETIF_F_NETNS_LOCAL; 118 } 119 120 static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[]) 121 { 122 if (tb[IFLA_ADDRESS]) { 123 if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN) 124 return -EINVAL; 125 } 126 return 0; 127 } 128 129 static int lowpan_newlink(struct net *src_net, struct net_device *ldev, 130 struct nlattr *tb[], struct nlattr *data[]) 131 { 132 struct net_device *wdev; 133 int ret; 134 135 ASSERT_RTNL(); 136 137 pr_debug("adding new link\n"); 138 139 if (!tb[IFLA_LINK] || 140 !net_eq(dev_net(ldev), &init_net)) 141 return -EINVAL; 142 /* find and hold wpan device */ 143 wdev = dev_get_by_index(dev_net(ldev), nla_get_u32(tb[IFLA_LINK])); 144 if (!wdev) 145 return -ENODEV; 146 if (wdev->type != ARPHRD_IEEE802154) { 147 dev_put(wdev); 148 return -EINVAL; 149 } 150 151 if (wdev->ieee802154_ptr->lowpan_dev) { 152 dev_put(wdev); 153 return -EBUSY; 154 } 155 156 lowpan_dev_info(ldev)->wdev = wdev; 157 /* Set the lowpan hardware address to the wpan hardware address. */ 158 memcpy(ldev->dev_addr, wdev->dev_addr, IEEE802154_ADDR_LEN); 159 160 lowpan_netdev_setup(ldev, LOWPAN_LLTYPE_IEEE802154); 161 162 ret = register_netdevice(ldev); 163 if (ret < 0) { 164 dev_put(wdev); 165 return ret; 166 } 167 168 wdev->ieee802154_ptr->lowpan_dev = ldev; 169 return 0; 170 } 171 172 static void lowpan_dellink(struct net_device *ldev, struct list_head *head) 173 { 174 struct net_device *wdev = lowpan_dev_info(ldev)->wdev; 175 176 ASSERT_RTNL(); 177 178 wdev->ieee802154_ptr->lowpan_dev = NULL; 179 unregister_netdevice(ldev); 180 dev_put(wdev); 181 } 182 183 static struct rtnl_link_ops lowpan_link_ops __read_mostly = { 184 .kind = "lowpan", 185 .priv_size = LOWPAN_PRIV_SIZE(sizeof(struct lowpan_dev_info)), 186 .setup = lowpan_setup, 187 .newlink = lowpan_newlink, 188 .dellink = lowpan_dellink, 189 .validate = lowpan_validate, 190 }; 191 192 static inline int __init lowpan_netlink_init(void) 193 { 194 return rtnl_link_register(&lowpan_link_ops); 195 } 196 197 static inline void lowpan_netlink_fini(void) 198 { 199 rtnl_link_unregister(&lowpan_link_ops); 200 } 201 202 static int lowpan_device_event(struct notifier_block *unused, 203 unsigned long event, void *ptr) 204 { 205 struct net_device *wdev = netdev_notifier_info_to_dev(ptr); 206 207 if (wdev->type != ARPHRD_IEEE802154) 208 goto out; 209 210 switch (event) { 211 case NETDEV_UNREGISTER: 212 /* Check if wpan interface is unregistered that we 213 * also delete possible lowpan interfaces which belongs 214 * to the wpan interface. 215 */ 216 if (wdev->ieee802154_ptr->lowpan_dev) 217 lowpan_dellink(wdev->ieee802154_ptr->lowpan_dev, NULL); 218 break; 219 default: 220 break; 221 } 222 223 out: 224 return NOTIFY_DONE; 225 } 226 227 static struct notifier_block lowpan_dev_notifier = { 228 .notifier_call = lowpan_device_event, 229 }; 230 231 static int __init lowpan_init_module(void) 232 { 233 int err = 0; 234 235 err = lowpan_net_frag_init(); 236 if (err < 0) 237 goto out; 238 239 err = lowpan_netlink_init(); 240 if (err < 0) 241 goto out_frag; 242 243 err = register_netdevice_notifier(&lowpan_dev_notifier); 244 if (err < 0) 245 goto out_pack; 246 247 return 0; 248 249 out_pack: 250 lowpan_netlink_fini(); 251 out_frag: 252 lowpan_net_frag_exit(); 253 out: 254 return err; 255 } 256 257 static void __exit lowpan_cleanup_module(void) 258 { 259 lowpan_netlink_fini(); 260 261 lowpan_net_frag_exit(); 262 263 unregister_netdevice_notifier(&lowpan_dev_notifier); 264 } 265 266 module_init(lowpan_init_module); 267 module_exit(lowpan_cleanup_module); 268 MODULE_LICENSE("GPL"); 269 MODULE_ALIAS_RTNL_LINK("lowpan"); 270