dgram.c revision bceaa90240b6019ed73b49965eac7d167610be69 
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 int bound:1;
48	unsigned int 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 int mtu;
210	struct sk_buff *skb;
211	struct dgram_sock *ro = dgram_sk(sk);
212	int hlen, tlen;
213	int err;
214
215	if (msg->msg_flags & MSG_OOB) {
216		pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
217		return -EOPNOTSUPP;
218	}
219
220	if (!ro->bound)
221		dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
222	else
223		dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
224
225	if (!dev) {
226		pr_debug("no dev\n");
227		err = -ENXIO;
228		goto out;
229	}
230	mtu = dev->mtu;
231	pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
232
233	if (size > mtu) {
234		pr_debug("size = %Zu, mtu = %u\n", size, mtu);
235		err = -EINVAL;
236		goto out_dev;
237	}
238
239	hlen = LL_RESERVED_SPACE(dev);
240	tlen = dev->needed_tailroom;
241	skb = sock_alloc_send_skb(sk, hlen + tlen + size,
242			msg->msg_flags & MSG_DONTWAIT,
243			&err);
244	if (!skb)
245		goto out_dev;
246
247	skb_reserve(skb, hlen);
248
249	skb_reset_network_header(skb);
250
251	mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
252	if (ro->want_ack)
253		mac_cb(skb)->flags |= MAC_CB_FLAG_ACKREQ;
254
255	mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
256	err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
257			ro->bound ? &ro->src_addr : NULL, size);
258	if (err < 0)
259		goto out_skb;
260
261	skb_reset_mac_header(skb);
262
263	err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
264	if (err < 0)
265		goto out_skb;
266
267	skb->dev = dev;
268	skb->sk  = sk;
269	skb->protocol = htons(ETH_P_IEEE802154);
270
271	dev_put(dev);
272
273	err = dev_queue_xmit(skb);
274	if (err > 0)
275		err = net_xmit_errno(err);
276
277	return err ?: size;
278
279out_skb:
280	kfree_skb(skb);
281out_dev:
282	dev_put(dev);
283out:
284	return err;
285}
286
287static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
288		struct msghdr *msg, size_t len, int noblock, int flags,
289		int *addr_len)
290{
291	size_t copied = 0;
292	int err = -EOPNOTSUPP;
293	struct sk_buff *skb;
294	struct sockaddr_ieee802154 *saddr;
295
296	saddr = (struct sockaddr_ieee802154 *)msg->msg_name;
297
298	skb = skb_recv_datagram(sk, flags, noblock, &err);
299	if (!skb)
300		goto out;
301
302	copied = skb->len;
303	if (len < copied) {
304		msg->msg_flags |= MSG_TRUNC;
305		copied = len;
306	}
307
308	/* FIXME: skip headers if necessary ?! */
309	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
310	if (err)
311		goto done;
312
313	sock_recv_ts_and_drops(msg, sk, skb);
314
315	if (saddr) {
316		saddr->family = AF_IEEE802154;
317		saddr->addr = mac_cb(skb)->sa;
318		*addr_len = sizeof(*saddr);
319	}
320
321	if (flags & MSG_TRUNC)
322		copied = skb->len;
323done:
324	skb_free_datagram(sk, skb);
325out:
326	if (err)
327		return err;
328	return copied;
329}
330
331static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
332{
333	if (sock_queue_rcv_skb(sk, skb) < 0) {
334		kfree_skb(skb);
335		return NET_RX_DROP;
336	}
337
338	return NET_RX_SUCCESS;
339}
340
341static inline int ieee802154_match_sock(u8 *hw_addr, u16 pan_id,
342		u16 short_addr, struct dgram_sock *ro)
343{
344	if (!ro->bound)
345		return 1;
346
347	if (ro->src_addr.addr_type == IEEE802154_ADDR_LONG &&
348	    !memcmp(ro->src_addr.hwaddr, hw_addr, IEEE802154_ADDR_LEN))
349		return 1;
350
351	if (ro->src_addr.addr_type == IEEE802154_ADDR_SHORT &&
352		     pan_id == ro->src_addr.pan_id &&
353		     short_addr == ro->src_addr.short_addr)
354		return 1;
355
356	return 0;
357}
358
359int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
360{
361	struct sock *sk, *prev = NULL;
362	int ret = NET_RX_SUCCESS;
363	u16 pan_id, short_addr;
364
365	/* Data frame processing */
366	BUG_ON(dev->type != ARPHRD_IEEE802154);
367
368	pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
369	short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
370
371	read_lock(&dgram_lock);
372	sk_for_each(sk, &dgram_head) {
373		if (ieee802154_match_sock(dev->dev_addr, pan_id, short_addr,
374					dgram_sk(sk))) {
375			if (prev) {
376				struct sk_buff *clone;
377				clone = skb_clone(skb, GFP_ATOMIC);
378				if (clone)
379					dgram_rcv_skb(prev, clone);
380			}
381
382			prev = sk;
383		}
384	}
385
386	if (prev)
387		dgram_rcv_skb(prev, skb);
388	else {
389		kfree_skb(skb);
390		ret = NET_RX_DROP;
391	}
392	read_unlock(&dgram_lock);
393
394	return ret;
395}
396
397static int dgram_getsockopt(struct sock *sk, int level, int optname,
398		    char __user *optval, int __user *optlen)
399{
400	struct dgram_sock *ro = dgram_sk(sk);
401
402	int val, len;
403
404	if (level != SOL_IEEE802154)
405		return -EOPNOTSUPP;
406
407	if (get_user(len, optlen))
408		return -EFAULT;
409
410	len = min_t(unsigned int, len, sizeof(int));
411
412	switch (optname) {
413	case WPAN_WANTACK:
414		val = ro->want_ack;
415		break;
416	default:
417		return -ENOPROTOOPT;
418	}
419
420	if (put_user(len, optlen))
421		return -EFAULT;
422	if (copy_to_user(optval, &val, len))
423		return -EFAULT;
424	return 0;
425}
426
427static int dgram_setsockopt(struct sock *sk, int level, int optname,
428		    char __user *optval, unsigned int optlen)
429{
430	struct dgram_sock *ro = dgram_sk(sk);
431	int val;
432	int err = 0;
433
434	if (optlen < sizeof(int))
435		return -EINVAL;
436
437	if (get_user(val, (int __user *)optval))
438		return -EFAULT;
439
440	lock_sock(sk);
441
442	switch (optname) {
443	case WPAN_WANTACK:
444		ro->want_ack = !!val;
445		break;
446	default:
447		err = -ENOPROTOOPT;
448		break;
449	}
450
451	release_sock(sk);
452	return err;
453}
454
455struct proto ieee802154_dgram_prot = {
456	.name		= "IEEE-802.15.4-MAC",
457	.owner		= THIS_MODULE,
458	.obj_size	= sizeof(struct dgram_sock),
459	.init		= dgram_init,
460	.close		= dgram_close,
461	.bind		= dgram_bind,
462	.sendmsg	= dgram_sendmsg,
463	.recvmsg	= dgram_recvmsg,
464	.hash		= dgram_hash,
465	.unhash		= dgram_unhash,
466	.connect	= dgram_connect,
467	.disconnect	= dgram_disconnect,
468	.ioctl		= dgram_ioctl,
469	.getsockopt	= dgram_getsockopt,
470	.setsockopt	= dgram_setsockopt,
471};
472
473