dgram.c revision 5fd72607a4e9a4a7147d670526431944976035b8 
1/*
2 * IEEE 802.15.4 dgram socket interface
3 *
4 * Copyright 2007, 2008 Siemens AG
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2
8 * as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Written by:
20 * Sergey Lapin <slapin@ossfans.org>
21 * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
22 */
23
24#include <linux/net.h>
25#include <linux/module.h>
26#include <linux/if_arp.h>
27#include <linux/list.h>
28#include <linux/slab.h>
29#include <net/sock.h>
30#include <net/af_ieee802154.h>
31#include <net/ieee802154.h>
32#include <net/ieee802154_netdev.h>
33
34#include <asm/ioctls.h>
35
36#include "af802154.h"
37
38static HLIST_HEAD(dgram_head);
39static DEFINE_RWLOCK(dgram_lock);
40
41struct dgram_sock {
42	struct sock sk;
43
44	struct ieee802154_addr src_addr;
45	struct ieee802154_addr dst_addr;
46
47	unsigned bound:1;
48	unsigned want_ack:1;
49};
50
51static inline struct dgram_sock *dgram_sk(const struct sock *sk)
52{
53	return container_of(sk, struct dgram_sock, sk);
54}
55
56static void dgram_hash(struct sock *sk)
57{
58	write_lock_bh(&dgram_lock);
59	sk_add_node(sk, &dgram_head);
60	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
61	write_unlock_bh(&dgram_lock);
62}
63
64static void dgram_unhash(struct sock *sk)
65{
66	write_lock_bh(&dgram_lock);
67	if (sk_del_node_init(sk))
68		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
69	write_unlock_bh(&dgram_lock);
70}
71
72static int dgram_init(struct sock *sk)
73{
74	struct dgram_sock *ro = dgram_sk(sk);
75
76	ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
77	ro->dst_addr.pan_id = 0xffff;
78	ro->want_ack = 1;
79	memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
80	return 0;
81}
82
83static void dgram_close(struct sock *sk, long timeout)
84{
85	sk_common_release(sk);
86}
87
88static int dgram_bind(struct sock *sk, struct sockaddr *uaddr, int len)
89{
90	struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
91	struct dgram_sock *ro = dgram_sk(sk);
92	int err = -EINVAL;
93	struct net_device *dev;
94
95	lock_sock(sk);
96
97	ro->bound = 0;
98
99	if (len < sizeof(*addr))
100		goto out;
101
102	if (addr->family != AF_IEEE802154)
103		goto out;
104
105	dev = ieee802154_get_dev(sock_net(sk), &addr->addr);
106	if (!dev) {
107		err = -ENODEV;
108		goto out;
109	}
110
111	if (dev->type != ARPHRD_IEEE802154) {
112		err = -ENODEV;
113		goto out_put;
114	}
115
116	memcpy(&ro->src_addr, &addr->addr, sizeof(struct ieee802154_addr));
117
118	ro->bound = 1;
119	err = 0;
120out_put:
121	dev_put(dev);
122out:
123	release_sock(sk);
124
125	return err;
126}
127
128static int dgram_ioctl(struct sock *sk, int cmd, unsigned long arg)
129{
130	switch (cmd) {
131	case SIOCOUTQ:
132	{
133		int amount = sk_wmem_alloc_get(sk);
134
135		return put_user(amount, (int __user *)arg);
136	}
137
138	case SIOCINQ:
139	{
140		struct sk_buff *skb;
141		unsigned long amount;
142
143		amount = 0;
144		spin_lock_bh(&sk->sk_receive_queue.lock);
145		skb = skb_peek(&sk->sk_receive_queue);
146		if (skb != NULL) {
147			/*
148			 * We will only return the amount
149			 * of this packet since that is all
150			 * that will be read.
151			 */
152			/* FIXME: parse the header for more correct value */
153			amount = skb->len - (3+8+8);
154		}
155		spin_unlock_bh(&sk->sk_receive_queue.lock);
156		return put_user(amount, (int __user *)arg);
157	}
158
159	}
160	return -ENOIOCTLCMD;
161}
162
163/* FIXME: autobind */
164static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
165			int len)
166{
167	struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
168	struct dgram_sock *ro = dgram_sk(sk);
169	int err = 0;
170
171	if (len < sizeof(*addr))
172		return -EINVAL;
173
174	if (addr->family != AF_IEEE802154)
175		return -EINVAL;
176
177	lock_sock(sk);
178
179	if (!ro->bound) {
180		err = -ENETUNREACH;
181		goto out;
182	}
183
184	memcpy(&ro->dst_addr, &addr->addr, sizeof(struct ieee802154_addr));
185
186out:
187	release_sock(sk);
188	return err;
189}
190
191static int dgram_disconnect(struct sock *sk, int flags)
192{
193	struct dgram_sock *ro = dgram_sk(sk);
194
195	lock_sock(sk);
196
197	ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
198	memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
199
200	release_sock(sk);
201
202	return 0;
203}
204
205static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
206		struct msghdr *msg, size_t size)
207{
208	struct net_device *dev;
209	unsigned mtu;
210	struct sk_buff *skb;
211	struct dgram_sock *ro = dgram_sk(sk);
212	int err;
213
214	if (msg->msg_flags & MSG_OOB) {
215		pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
216		return -EOPNOTSUPP;
217	}
218
219	if (!ro->bound)
220		dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
221	else
222		dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
223
224	if (!dev) {
225		pr_debug("no dev\n");
226		err = -ENXIO;
227		goto out;
228	}
229	mtu = dev->mtu;
230	pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
231
232	skb = sock_alloc_send_skb(sk, LL_ALLOCATED_SPACE(dev) + size,
233			msg->msg_flags & MSG_DONTWAIT,
234			&err);
235	if (!skb)
236		goto out_dev;
237
238	skb_reserve(skb, LL_RESERVED_SPACE(dev));
239
240	skb_reset_network_header(skb);
241
242	mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
243	if (ro->want_ack)
244		mac_cb(skb)->flags |= MAC_CB_FLAG_ACKREQ;
245
246	mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
247	err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
248			ro->bound ? &ro->src_addr : NULL, size);
249	if (err < 0)
250		goto out_skb;
251
252	skb_reset_mac_header(skb);
253
254	err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
255	if (err < 0)
256		goto out_skb;
257
258	if (size > mtu) {
259		pr_debug("size = %Zu, mtu = %u\n", size, mtu);
260		err = -EINVAL;
261		goto out_skb;
262	}
263
264	skb->dev = dev;
265	skb->sk  = sk;
266	skb->protocol = htons(ETH_P_IEEE802154);
267
268	dev_put(dev);
269
270	err = dev_queue_xmit(skb);
271	if (err > 0)
272		err = net_xmit_errno(err);
273
274	return err ?: size;
275
276out_skb:
277	kfree_skb(skb);
278out_dev:
279	dev_put(dev);
280out:
281	return err;
282}
283
284static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
285		struct msghdr *msg, size_t len, int noblock, int flags,
286		int *addr_len)
287{
288	size_t copied = 0;
289	int err = -EOPNOTSUPP;
290	struct sk_buff *skb;
291
292	skb = skb_recv_datagram(sk, flags, noblock, &err);
293	if (!skb)
294		goto out;
295
296	copied = skb->len;
297	if (len < copied) {
298		msg->msg_flags |= MSG_TRUNC;
299		copied = len;
300	}
301
302	/* FIXME: skip headers if necessary ?! */
303	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
304	if (err)
305		goto done;
306
307	sock_recv_ts_and_drops(msg, sk, skb);
308
309	if (flags & MSG_TRUNC)
310		copied = skb->len;
311done:
312	skb_free_datagram(sk, skb);
313out:
314	if (err)
315		return err;
316	return copied;
317}
318
319static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
320{
321	if (sock_queue_rcv_skb(sk, skb) < 0) {
322		kfree_skb(skb);
323		return NET_RX_DROP;
324	}
325
326	return NET_RX_SUCCESS;
327}
328
329static inline int ieee802154_match_sock(u8 *hw_addr, u16 pan_id,
330		u16 short_addr, struct dgram_sock *ro)
331{
332	if (!ro->bound)
333		return 1;
334
335	if (ro->src_addr.addr_type == IEEE802154_ADDR_LONG &&
336	    !memcmp(ro->src_addr.hwaddr, hw_addr, IEEE802154_ADDR_LEN))
337		return 1;
338
339	if (ro->src_addr.addr_type == IEEE802154_ADDR_SHORT &&
340		     pan_id == ro->src_addr.pan_id &&
341		     short_addr == ro->src_addr.short_addr)
342		return 1;
343
344	return 0;
345}
346
347int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
348{
349	struct sock *sk, *prev = NULL;
350	struct hlist_node *node;
351	int ret = NET_RX_SUCCESS;
352	u16 pan_id, short_addr;
353
354	/* Data frame processing */
355	BUG_ON(dev->type != ARPHRD_IEEE802154);
356
357	pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
358	short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
359
360	read_lock(&dgram_lock);
361	sk_for_each(sk, node, &dgram_head) {
362		if (ieee802154_match_sock(dev->dev_addr, pan_id, short_addr,
363					dgram_sk(sk))) {
364			if (prev) {
365				struct sk_buff *clone;
366				clone = skb_clone(skb, GFP_ATOMIC);
367				if (clone)
368					dgram_rcv_skb(prev, clone);
369			}
370
371			prev = sk;
372		}
373	}
374
375	if (prev)
376		dgram_rcv_skb(prev, skb);
377	else {
378		kfree_skb(skb);
379		ret = NET_RX_DROP;
380	}
381	read_unlock(&dgram_lock);
382
383	return ret;
384}
385
386static int dgram_getsockopt(struct sock *sk, int level, int optname,
387		    char __user *optval, int __user *optlen)
388{
389	struct dgram_sock *ro = dgram_sk(sk);
390
391	int val, len;
392
393	if (level != SOL_IEEE802154)
394		return -EOPNOTSUPP;
395
396	if (get_user(len, optlen))
397		return -EFAULT;
398
399	len = min_t(unsigned int, len, sizeof(int));
400
401	switch (optname) {
402	case WPAN_WANTACK:
403		val = ro->want_ack;
404		break;
405	default:
406		return -ENOPROTOOPT;
407	}
408
409	if (put_user(len, optlen))
410		return -EFAULT;
411	if (copy_to_user(optval, &val, len))
412		return -EFAULT;
413	return 0;
414}
415
416static int dgram_setsockopt(struct sock *sk, int level, int optname,
417		    char __user *optval, unsigned int optlen)
418{
419	struct dgram_sock *ro = dgram_sk(sk);
420	int val;
421	int err = 0;
422
423	if (optlen < sizeof(int))
424		return -EINVAL;
425
426	if (get_user(val, (int __user *)optval))
427		return -EFAULT;
428
429	lock_sock(sk);
430
431	switch (optname) {
432	case WPAN_WANTACK:
433		ro->want_ack = !!val;
434		break;
435	default:
436		err = -ENOPROTOOPT;
437		break;
438	}
439
440	release_sock(sk);
441	return err;
442}
443
444struct proto ieee802154_dgram_prot = {
445	.name		= "IEEE-802.15.4-MAC",
446	.owner		= THIS_MODULE,
447	.obj_size	= sizeof(struct dgram_sock),
448	.init		= dgram_init,
449	.close		= dgram_close,
450	.bind		= dgram_bind,
451	.sendmsg	= dgram_sendmsg,
452	.recvmsg	= dgram_recvmsg,
453	.hash		= dgram_hash,
454	.unhash		= dgram_unhash,
455	.connect	= dgram_connect,
456	.disconnect	= dgram_disconnect,
457	.ioctl		= dgram_ioctl,
458	.getsockopt	= dgram_getsockopt,
459	.setsockopt	= dgram_setsockopt,
460};
461
462