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