summaryrefslogtreecommitdiff
path: root/net/ieee802154/6lowpan/core.c
blob: 935ab932e841205b9584f2c00c142ac2da9636cf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
/* 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 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->destructor	= free_netdev;
	ldev->features		|= NETIF_F_NETNS_LOCAL;
}

static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[])
{
	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 net_device *wdev;
	int ret;

	ASSERT_RTNL();

	pr_debug("adding new link\n");

	if (!tb[IFLA_LINK] ||
	    !net_eq(dev_net(ldev), &init_net))
		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");