linux/net/ieee802154/6lowpan/core.c

273 lines
7.3 KiB
C

/* 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 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,
};
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->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 *wdev = netdev_notifier_info_to_dev(ptr);
if (wdev->type != ARPHRD_IEEE802154)
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 (wdev->ieee802154_ptr->lowpan_dev)
lowpan_dellink(wdev->ieee802154_ptr->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");