| /* Copyright 2011, Siemens AG | 
 |  * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com> | 
 |  */ | 
 |  | 
 | /* Based on patches from Jon Smirl <jonsmirl@gmail.com> | 
 |  * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com> | 
 |  * | 
 |  * This program is free software; you can redistribute it and/or modify | 
 |  * it under the terms of the GNU General Public License version 2 | 
 |  * as published by the Free Software Foundation. | 
 |  * | 
 |  * This program is distributed in the hope that it will be useful, | 
 |  * but WITHOUT ANY WARRANTY; without even the implied warranty of | 
 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
 |  * GNU General Public License for more details. | 
 |  */ | 
 |  | 
 | /* Jon's code is based on 6lowpan implementation for Contiki which is: | 
 |  * Copyright (c) 2008, Swedish Institute of Computer Science. | 
 |  * All rights reserved. | 
 |  * | 
 |  * Redistribution and use in source and binary forms, with or without | 
 |  * modification, are permitted provided that the following conditions | 
 |  * are met: | 
 |  * 1. Redistributions of source code must retain the above copyright | 
 |  *    notice, this list of conditions and the following disclaimer. | 
 |  * 2. Redistributions in binary form must reproduce the above copyright | 
 |  *    notice, this list of conditions and the following disclaimer in the | 
 |  *    documentation and/or other materials provided with the distribution. | 
 |  * 3. Neither the name of the Institute nor the names of its contributors | 
 |  *    may be used to endorse or promote products derived from this software | 
 |  *    without specific prior written permission. | 
 |  * | 
 |  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND | 
 |  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | 
 |  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | 
 |  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE | 
 |  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | 
 |  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | 
 |  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | 
 |  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | 
 |  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | 
 |  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | 
 |  * SUCH DAMAGE. | 
 |  */ | 
 |  | 
 | #include <linux/module.h> | 
 | #include <linux/netdevice.h> | 
 | #include <linux/ieee802154.h> | 
 |  | 
 | #include <net/ipv6.h> | 
 |  | 
 | #include "6lowpan_i.h" | 
 |  | 
 | static int open_count; | 
 |  | 
 | static const struct header_ops lowpan_header_ops = { | 
 | 	.create	= lowpan_header_create, | 
 | }; | 
 |  | 
 | static int lowpan_dev_init(struct net_device *ldev) | 
 | { | 
 | 	netdev_lockdep_set_classes(ldev); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int lowpan_open(struct net_device *dev) | 
 | { | 
 | 	if (!open_count) | 
 | 		lowpan_rx_init(); | 
 | 	open_count++; | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int lowpan_stop(struct net_device *dev) | 
 | { | 
 | 	open_count--; | 
 | 	if (!open_count) | 
 | 		lowpan_rx_exit(); | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int lowpan_neigh_construct(struct net_device *dev, struct neighbour *n) | 
 | { | 
 | 	struct lowpan_802154_neigh *neigh = lowpan_802154_neigh(neighbour_priv(n)); | 
 |  | 
 | 	/* default no short_addr is available for a neighbour */ | 
 | 	neigh->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_UNSPEC); | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int lowpan_get_iflink(const struct net_device *dev) | 
 | { | 
 | 	return lowpan_802154_dev(dev)->wdev->ifindex; | 
 | } | 
 |  | 
 | static const struct net_device_ops lowpan_netdev_ops = { | 
 | 	.ndo_init		= lowpan_dev_init, | 
 | 	.ndo_start_xmit		= lowpan_xmit, | 
 | 	.ndo_open		= lowpan_open, | 
 | 	.ndo_stop		= lowpan_stop, | 
 | 	.ndo_neigh_construct    = lowpan_neigh_construct, | 
 | 	.ndo_get_iflink         = lowpan_get_iflink, | 
 | }; | 
 |  | 
 | static void lowpan_setup(struct net_device *ldev) | 
 | { | 
 | 	memset(ldev->broadcast, 0xff, IEEE802154_ADDR_LEN); | 
 | 	/* We need an ipv6hdr as minimum len when calling xmit */ | 
 | 	ldev->hard_header_len	= sizeof(struct ipv6hdr); | 
 | 	ldev->flags		= IFF_BROADCAST | IFF_MULTICAST; | 
 | 	ldev->priv_flags	|= IFF_NO_QUEUE; | 
 |  | 
 | 	ldev->netdev_ops	= &lowpan_netdev_ops; | 
 | 	ldev->header_ops	= &lowpan_header_ops; | 
 | 	ldev->needs_free_netdev	= true; | 
 | 	ldev->features		|= NETIF_F_NETNS_LOCAL; | 
 | } | 
 |  | 
 | static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[], | 
 | 			   struct netlink_ext_ack *extack) | 
 | { | 
 | 	if (tb[IFLA_ADDRESS]) { | 
 | 		if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN) | 
 | 			return -EINVAL; | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int lowpan_newlink(struct net *src_net, struct net_device *ldev, | 
 | 			  struct nlattr *tb[], struct nlattr *data[], | 
 | 			  struct netlink_ext_ack *extack) | 
 | { | 
 | 	struct net_device *wdev; | 
 | 	int ret; | 
 |  | 
 | 	ASSERT_RTNL(); | 
 |  | 
 | 	pr_debug("adding new link\n"); | 
 |  | 
 | 	if (!tb[IFLA_LINK]) | 
 | 		return -EINVAL; | 
 | 	/* find and hold wpan device */ | 
 | 	wdev = dev_get_by_index(dev_net(ldev), nla_get_u32(tb[IFLA_LINK])); | 
 | 	if (!wdev) | 
 | 		return -ENODEV; | 
 | 	if (wdev->type != ARPHRD_IEEE802154) { | 
 | 		dev_put(wdev); | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	if (wdev->ieee802154_ptr->lowpan_dev) { | 
 | 		dev_put(wdev); | 
 | 		return -EBUSY; | 
 | 	} | 
 |  | 
 | 	lowpan_802154_dev(ldev)->wdev = wdev; | 
 | 	/* Set the lowpan hardware address to the wpan hardware address. */ | 
 | 	memcpy(ldev->dev_addr, wdev->dev_addr, IEEE802154_ADDR_LEN); | 
 | 	/* We need headroom for possible wpan_dev_hard_header call and tailroom | 
 | 	 * for encryption/fcs handling. The lowpan interface will replace | 
 | 	 * the IPv6 header with 6LoWPAN header. At worst case the 6LoWPAN | 
 | 	 * header has LOWPAN_IPHC_MAX_HEADER_LEN more bytes than the IPv6 | 
 | 	 * header. | 
 | 	 */ | 
 | 	ldev->needed_headroom = LOWPAN_IPHC_MAX_HEADER_LEN + | 
 | 				wdev->needed_headroom; | 
 | 	ldev->needed_tailroom = wdev->needed_tailroom; | 
 |  | 
 | 	ldev->neigh_priv_len = sizeof(struct lowpan_802154_neigh); | 
 |  | 
 | 	ret = lowpan_register_netdevice(ldev, LOWPAN_LLTYPE_IEEE802154); | 
 | 	if (ret < 0) { | 
 | 		dev_put(wdev); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	wdev->ieee802154_ptr->lowpan_dev = ldev; | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void lowpan_dellink(struct net_device *ldev, struct list_head *head) | 
 | { | 
 | 	struct net_device *wdev = lowpan_802154_dev(ldev)->wdev; | 
 |  | 
 | 	ASSERT_RTNL(); | 
 |  | 
 | 	wdev->ieee802154_ptr->lowpan_dev = NULL; | 
 | 	lowpan_unregister_netdevice(ldev); | 
 | 	dev_put(wdev); | 
 | } | 
 |  | 
 | static struct rtnl_link_ops lowpan_link_ops __read_mostly = { | 
 | 	.kind		= "lowpan", | 
 | 	.priv_size	= LOWPAN_PRIV_SIZE(sizeof(struct lowpan_802154_dev)), | 
 | 	.setup		= lowpan_setup, | 
 | 	.newlink	= lowpan_newlink, | 
 | 	.dellink	= lowpan_dellink, | 
 | 	.validate	= lowpan_validate, | 
 | }; | 
 |  | 
 | static inline int __init lowpan_netlink_init(void) | 
 | { | 
 | 	return rtnl_link_register(&lowpan_link_ops); | 
 | } | 
 |  | 
 | static inline void lowpan_netlink_fini(void) | 
 | { | 
 | 	rtnl_link_unregister(&lowpan_link_ops); | 
 | } | 
 |  | 
 | static int lowpan_device_event(struct notifier_block *unused, | 
 | 			       unsigned long event, void *ptr) | 
 | { | 
 | 	struct net_device *ndev = netdev_notifier_info_to_dev(ptr); | 
 | 	struct wpan_dev *wpan_dev; | 
 |  | 
 | 	if (ndev->type != ARPHRD_IEEE802154) | 
 | 		return NOTIFY_DONE; | 
 | 	wpan_dev = ndev->ieee802154_ptr; | 
 | 	if (!wpan_dev) | 
 | 		return NOTIFY_DONE; | 
 |  | 
 | 	switch (event) { | 
 | 	case NETDEV_UNREGISTER: | 
 | 		/* Check if wpan interface is unregistered that we | 
 | 		 * also delete possible lowpan interfaces which belongs | 
 | 		 * to the wpan interface. | 
 | 		 */ | 
 | 		if (wpan_dev->lowpan_dev) | 
 | 			lowpan_dellink(wpan_dev->lowpan_dev, NULL); | 
 | 		break; | 
 | 	default: | 
 | 		return NOTIFY_DONE; | 
 | 	} | 
 |  | 
 | 	return NOTIFY_OK; | 
 | } | 
 |  | 
 | static struct notifier_block lowpan_dev_notifier = { | 
 | 	.notifier_call = lowpan_device_event, | 
 | }; | 
 |  | 
 | static int __init lowpan_init_module(void) | 
 | { | 
 | 	int err = 0; | 
 |  | 
 | 	err = lowpan_net_frag_init(); | 
 | 	if (err < 0) | 
 | 		goto out; | 
 |  | 
 | 	err = lowpan_netlink_init(); | 
 | 	if (err < 0) | 
 | 		goto out_frag; | 
 |  | 
 | 	err = register_netdevice_notifier(&lowpan_dev_notifier); | 
 | 	if (err < 0) | 
 | 		goto out_pack; | 
 |  | 
 | 	return 0; | 
 |  | 
 | out_pack: | 
 | 	lowpan_netlink_fini(); | 
 | out_frag: | 
 | 	lowpan_net_frag_exit(); | 
 | out: | 
 | 	return err; | 
 | } | 
 |  | 
 | static void __exit lowpan_cleanup_module(void) | 
 | { | 
 | 	lowpan_netlink_fini(); | 
 |  | 
 | 	lowpan_net_frag_exit(); | 
 |  | 
 | 	unregister_netdevice_notifier(&lowpan_dev_notifier); | 
 | } | 
 |  | 
 | module_init(lowpan_init_module); | 
 | module_exit(lowpan_cleanup_module); | 
 | MODULE_LICENSE("GPL"); | 
 | MODULE_ALIAS_RTNL_LINK("lowpan"); |