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 #include <linux/if_arp.h> 51 52 #include <net/ipv6.h> 53 54 #include "6lowpan_i.h" 55 56 static int open_count; 57 58 static const struct header_ops lowpan_header_ops = { 59 .create = lowpan_header_create, 60 }; 61 62 static int lowpan_dev_init(struct net_device *ldev) 63 { 64 netdev_lockdep_set_classes(ldev); 65 66 return 0; 67 } 68 69 static int lowpan_open(struct net_device *dev) 70 { 71 if (!open_count) 72 lowpan_rx_init(); 73 open_count++; 74 return 0; 75 } 76 77 static int lowpan_stop(struct net_device *dev) 78 { 79 open_count--; 80 if (!open_count) 81 lowpan_rx_exit(); 82 return 0; 83 } 84 85 static int lowpan_neigh_construct(struct net_device *dev, struct neighbour *n) 86 { 87 struct lowpan_802154_neigh *neigh = lowpan_802154_neigh(neighbour_priv(n)); 88 89 /* default no short_addr is available for a neighbour */ 90 neigh->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC); 91 return 0; 92 } 93 94 static int lowpan_get_iflink(const struct net_device *dev) 95 { 96 return lowpan_802154_dev(dev)->wdev->ifindex; 97 } 98 99 static const struct net_device_ops lowpan_netdev_ops = { 100 .ndo_init = lowpan_dev_init, 101 .ndo_start_xmit = lowpan_xmit, 102 .ndo_open = lowpan_open, 103 .ndo_stop = lowpan_stop, 104 .ndo_neigh_construct = lowpan_neigh_construct, 105 .ndo_get_iflink = lowpan_get_iflink, 106 }; 107 108 static void lowpan_setup(struct net_device *ldev) 109 { 110 memset(ldev->broadcast, 0xff, IEEE802154_ADDR_LEN); 111 /* We need an ipv6hdr as minimum len when calling xmit */ 112 ldev->hard_header_len = sizeof(struct ipv6hdr); 113 ldev->flags = IFF_BROADCAST | IFF_MULTICAST; 114 ldev->priv_flags |= IFF_NO_QUEUE; 115 116 ldev->netdev_ops = &lowpan_netdev_ops; 117 ldev->header_ops = &lowpan_header_ops; 118 ldev->needs_free_netdev = true; 119 ldev->features |= NETIF_F_NETNS_LOCAL; 120 } 121 122 static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[], 123 struct netlink_ext_ack *extack) 124 { 125 if (tb[IFLA_ADDRESS]) { 126 if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN) 127 return -EINVAL; 128 } 129 return 0; 130 } 131 132 static int lowpan_newlink(struct net *src_net, struct net_device *ldev, 133 struct nlattr *tb[], struct nlattr *data[], 134 struct netlink_ext_ack *extack) 135 { 136 struct net_device *wdev; 137 int ret; 138 139 ASSERT_RTNL(); 140 141 pr_debug("adding new link\n"); 142 143 if (!tb[IFLA_LINK]) 144 return -EINVAL; 145 /* find and hold wpan device */ 146 wdev = dev_get_by_index(dev_net(ldev), nla_get_u32(tb[IFLA_LINK])); 147 if (!wdev) 148 return -ENODEV; 149 if (wdev->type != ARPHRD_IEEE802154) { 150 dev_put(wdev); 151 return -EINVAL; 152 } 153 154 if (wdev->ieee802154_ptr->lowpan_dev) { 155 dev_put(wdev); 156 return -EBUSY; 157 } 158 159 lowpan_802154_dev(ldev)->wdev = wdev; 160 /* Set the lowpan hardware address to the wpan hardware address. */ 161 __dev_addr_set(ldev, wdev->dev_addr, IEEE802154_ADDR_LEN); 162 /* We need headroom for possible wpan_dev_hard_header call and tailroom 163 * for encryption/fcs handling. The lowpan interface will replace 164 * the IPv6 header with 6LoWPAN header. At worst case the 6LoWPAN 165 * header has LOWPAN_IPHC_MAX_HEADER_LEN more bytes than the IPv6 166 * header. 167 */ 168 ldev->needed_headroom = LOWPAN_IPHC_MAX_HEADER_LEN + 169 wdev->needed_headroom; 170 ldev->needed_tailroom = wdev->needed_tailroom; 171 172 ldev->neigh_priv_len = sizeof(struct lowpan_802154_neigh); 173 174 ret = lowpan_register_netdevice(ldev, LOWPAN_LLTYPE_IEEE802154); 175 if (ret < 0) { 176 dev_put(wdev); 177 return ret; 178 } 179 180 wdev->ieee802154_ptr->lowpan_dev = ldev; 181 return 0; 182 } 183 184 static void lowpan_dellink(struct net_device *ldev, struct list_head *head) 185 { 186 struct net_device *wdev = lowpan_802154_dev(ldev)->wdev; 187 188 ASSERT_RTNL(); 189 190 wdev->ieee802154_ptr->lowpan_dev = NULL; 191 lowpan_unregister_netdevice(ldev); 192 dev_put(wdev); 193 } 194 195 static struct rtnl_link_ops lowpan_link_ops __read_mostly = { 196 .kind = "lowpan", 197 .priv_size = LOWPAN_PRIV_SIZE(sizeof(struct lowpan_802154_dev)), 198 .setup = lowpan_setup, 199 .newlink = lowpan_newlink, 200 .dellink = lowpan_dellink, 201 .validate = lowpan_validate, 202 }; 203 204 static inline int __init lowpan_netlink_init(void) 205 { 206 return rtnl_link_register(&lowpan_link_ops); 207 } 208 209 static inline void lowpan_netlink_fini(void) 210 { 211 rtnl_link_unregister(&lowpan_link_ops); 212 } 213 214 static int lowpan_device_event(struct notifier_block *unused, 215 unsigned long event, void *ptr) 216 { 217 struct net_device *ndev = netdev_notifier_info_to_dev(ptr); 218 struct wpan_dev *wpan_dev; 219 220 if (ndev->type != ARPHRD_IEEE802154) 221 return NOTIFY_DONE; 222 wpan_dev = ndev->ieee802154_ptr; 223 if (!wpan_dev) 224 return NOTIFY_DONE; 225 226 switch (event) { 227 case NETDEV_UNREGISTER: 228 /* Check if wpan interface is unregistered that we 229 * also delete possible lowpan interfaces which belongs 230 * to the wpan interface. 231 */ 232 if (wpan_dev->lowpan_dev) 233 lowpan_dellink(wpan_dev->lowpan_dev, NULL); 234 break; 235 default: 236 return NOTIFY_DONE; 237 } 238 239 return NOTIFY_OK; 240 } 241 242 static struct notifier_block lowpan_dev_notifier = { 243 .notifier_call = lowpan_device_event, 244 }; 245 246 static int __init lowpan_init_module(void) 247 { 248 int err = 0; 249 250 err = lowpan_net_frag_init(); 251 if (err < 0) 252 goto out; 253 254 err = lowpan_netlink_init(); 255 if (err < 0) 256 goto out_frag; 257 258 err = register_netdevice_notifier(&lowpan_dev_notifier); 259 if (err < 0) 260 goto out_pack; 261 262 return 0; 263 264 out_pack: 265 lowpan_netlink_fini(); 266 out_frag: 267 lowpan_net_frag_exit(); 268 out: 269 return err; 270 } 271 272 static void __exit lowpan_cleanup_module(void) 273 { 274 lowpan_netlink_fini(); 275 276 lowpan_net_frag_exit(); 277 278 unregister_netdevice_notifier(&lowpan_dev_notifier); 279 } 280 281 module_init(lowpan_init_module); 282 module_exit(lowpan_cleanup_module); 283 MODULE_LICENSE("GPL"); 284 MODULE_ALIAS_RTNL_LINK("lowpan"); 285