net/ieee802154/dgram.c - linux - Git at Google

 /*
  * ZigBee socket interface
  *
  * Copyright 2007, 2008 Siemens AG
  *
  * 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.
  *
  * You should have received a copy of the GNU General Public License along
  * with this program; if not, write to the Free Software Foundation, Inc.,
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Written by:
  * Sergey Lapin <slapin@ossfans.org>
  * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
  */

 #include <linux/net.h>
 #include <linux/module.h>
 #include <linux/if_arp.h>
 #include <linux/list.h>
 #include <net/sock.h>
 #include <net/af_ieee802154.h>
 #include <net/ieee802154.h>
 #include <net/ieee802154_netdev.h>

 #include <asm/ioctls.h>

 #include "af802154.h"

 static HLIST_HEAD(dgram_head);
 static DEFINE_RWLOCK(dgram_lock);

 struct dgram_sock {
 	struct sock sk;

 	struct ieee802154_addr src_addr;
 	struct ieee802154_addr dst_addr;

 	unsigned bound:1;
 	unsigned want_ack:1;
 };

 static inline struct dgram_sock *dgram_sk(const struct sock *sk)
 {
 	return container_of(sk, struct dgram_sock, sk);
 }

 static void dgram_hash(struct sock *sk)
 {
 	write_lock_bh(&dgram_lock);
 	sk_add_node(sk, &dgram_head);
 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 	write_unlock_bh(&dgram_lock);
 }

 static void dgram_unhash(struct sock *sk)
 {
 	write_lock_bh(&dgram_lock);
 	if (sk_del_node_init(sk))
 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
 	write_unlock_bh(&dgram_lock);
 }

 static int dgram_init(struct sock *sk)
 {
 	struct dgram_sock *ro = dgram_sk(sk);

 	ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
 	ro->dst_addr.pan_id = 0xffff;
 	ro->want_ack = 1;
 	memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
 	return 0;
 }

 static void dgram_close(struct sock *sk, long timeout)
 {
 	sk_common_release(sk);
 }

 static int dgram_bind(struct sock *sk, struct sockaddr *uaddr, int len)
 {
 	struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
 	struct dgram_sock *ro = dgram_sk(sk);
 	int err = -EINVAL;
 	struct net_device *dev;

 	lock_sock(sk);

 	ro->bound = 0;

 	if (len < sizeof(*addr))
 		goto out;

 	if (addr->family != AF_IEEE802154)
 		goto out;

 	dev = ieee802154_get_dev(sock_net(sk), &addr->addr);
 	if (!dev) {
 		err = -ENODEV;
 		goto out;
 	}

 	if (dev->type != ARPHRD_IEEE802154) {
 		err = -ENODEV;
 		goto out_put;
 	}

 	memcpy(&ro->src_addr, &addr->addr, sizeof(struct ieee802154_addr));

 	ro->bound = 1;
 	err = 0;
 out_put:
 	dev_put(dev);
 out:
 	release_sock(sk);

 	return err;
 }

 static int dgram_ioctl(struct sock *sk, int cmd, unsigned long arg)
 {
 	switch (cmd) {
 	case SIOCOUTQ:
 	{
 		int amount = sk_wmem_alloc_get(sk);

 		return put_user(amount, (int __user *)arg);
 	}

 	case SIOCINQ:
 	{
 		struct sk_buff *skb;
 		unsigned long amount;

 		amount = 0;
 		spin_lock_bh(&sk->sk_receive_queue.lock);
 		skb = skb_peek(&sk->sk_receive_queue);
 		if (skb != NULL) {
 			/*
 			 * We will only return the amount
 			 * of this packet since that is all
 			 * that will be read.
 			 */
 			/* FIXME: parse the header for more correct value */
 			amount = skb->len - (3+8+8);
 		}
 		spin_unlock_bh(&sk->sk_receive_queue.lock);
 		return put_user(amount, (int __user *)arg);
 	}

 	}
 	return -ENOIOCTLCMD;
 }

 /* FIXME: autobind */
 static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
 			int len)
 {
 	struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
 	struct dgram_sock *ro = dgram_sk(sk);
 	int err = 0;

 	if (len < sizeof(*addr))
 		return -EINVAL;

 	if (addr->family != AF_IEEE802154)
 		return -EINVAL;

 	lock_sock(sk);

 	if (!ro->bound) {
 		err = -ENETUNREACH;
 		goto out;
 	}

 	memcpy(&ro->dst_addr, &addr->addr, sizeof(struct ieee802154_addr));

 out:
 	release_sock(sk);
 	return err;
 }

 static int dgram_disconnect(struct sock *sk, int flags)
 {
 	struct dgram_sock *ro = dgram_sk(sk);

 	lock_sock(sk);

 	ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
 	memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));

 	release_sock(sk);

 	return 0;
 }

 static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
 		struct msghdr *msg, size_t size)
 {
 	struct net_device *dev;
 	unsigned mtu;
 	struct sk_buff *skb;
 	struct dgram_sock *ro = dgram_sk(sk);
 	int err;

 	if (msg->msg_flags & MSG_OOB) {
 		pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
 		return -EOPNOTSUPP;
 	}

 	if (!ro->bound)
 		dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
 	else
 		dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);

 	if (!dev) {
 		pr_debug("no dev\n");
 		err = -ENXIO;
 		goto out;
 	}
 	mtu = dev->mtu;
 	pr_debug("name = %s, mtu = %u\n", dev->name, mtu);

 	skb = sock_alloc_send_skb(sk, LL_ALLOCATED_SPACE(dev) + size,
 			msg->msg_flags & MSG_DONTWAIT,
 			&err);
 	if (!skb)
 		goto out_dev;

 	skb_reserve(skb, LL_RESERVED_SPACE(dev));

 	skb_reset_network_header(skb);

 	mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
 	if (ro->want_ack)
 		mac_cb(skb)->flags |= MAC_CB_FLAG_ACKREQ;

 	mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
 	err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
 			ro->bound ? &ro->src_addr : NULL, size);
 	if (err < 0)
 		goto out_skb;

 	skb_reset_mac_header(skb);

 	err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 	if (err < 0)
 		goto out_skb;

 	if (size > mtu) {
 		pr_debug("size = %Zu, mtu = %u\n", size, mtu);
 		err = -EINVAL;
 		goto out_skb;
 	}

 	skb->dev = dev;
 	skb->sk  = sk;
 	skb->protocol = htons(ETH_P_IEEE802154);

 	dev_put(dev);

 	err = dev_queue_xmit(skb);
 	if (err > 0)
 		err = net_xmit_errno(err);

 	return err ?: size;

 out_skb:
 	kfree_skb(skb);
 out_dev:
 	dev_put(dev);
 out:
 	return err;
 }

 static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
 		struct msghdr *msg, size_t len, int noblock, int flags,
 		int *addr_len)
 {
 	size_t copied = 0;
 	int err = -EOPNOTSUPP;
 	struct sk_buff *skb;

 	skb = skb_recv_datagram(sk, flags, noblock, &err);
 	if (!skb)
 		goto out;

 	copied = skb->len;
 	if (len < copied) {
 		msg->msg_flags |= MSG_TRUNC;
 		copied = len;
 	}

 	/* FIXME: skip headers if necessary ?! */
 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 	if (err)
 		goto done;

 	sock_recv_ts_and_drops(msg, sk, skb);

 	if (flags & MSG_TRUNC)
 		copied = skb->len;
 done:
 	skb_free_datagram(sk, skb);
 out:
 	if (err)
 		return err;
 	return copied;
 }

 static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
 	if (sock_queue_rcv_skb(sk, skb) < 0) {
 		atomic_inc(&sk->sk_drops);
 		kfree_skb(skb);
 		return NET_RX_DROP;
 	}

 	return NET_RX_SUCCESS;
 }

 static inline int ieee802154_match_sock(u8 *hw_addr, u16 pan_id,
 		u16 short_addr, struct dgram_sock *ro)
 {
 	if (!ro->bound)
 		return 1;

 	if (ro->src_addr.addr_type == IEEE802154_ADDR_LONG &&
 	    !memcmp(ro->src_addr.hwaddr, hw_addr, IEEE802154_ADDR_LEN))
 		return 1;

 	if (ro->src_addr.addr_type == IEEE802154_ADDR_SHORT &&
 		     pan_id == ro->src_addr.pan_id &&
 		     short_addr == ro->src_addr.short_addr)
 		return 1;

 	return 0;
 }

 int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
 {
 	struct sock *sk, *prev = NULL;
 	struct hlist_node *node;
 	int ret = NET_RX_SUCCESS;
 	u16 pan_id, short_addr;

 	/* Data frame processing */
 	BUG_ON(dev->type != ARPHRD_IEEE802154);

 	pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
 	short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);

 	read_lock(&dgram_lock);
 	sk_for_each(sk, node, &dgram_head) {
 		if (ieee802154_match_sock(dev->dev_addr, pan_id, short_addr,
 					dgram_sk(sk))) {
 			if (prev) {
 				struct sk_buff *clone;
 				clone = skb_clone(skb, GFP_ATOMIC);
 				if (clone)
 					dgram_rcv_skb(prev, clone);
 			}

 			prev = sk;
 		}
 	}

 	if (prev)
 		dgram_rcv_skb(prev, skb);
 	else {
 		kfree_skb(skb);
 		ret = NET_RX_DROP;
 	}
 	read_unlock(&dgram_lock);

 	return ret;
 }

 static int dgram_getsockopt(struct sock *sk, int level, int optname,
 		    char __user *optval, int __user *optlen)
 {
 	struct dgram_sock *ro = dgram_sk(sk);

 	int val, len;

 	if (level != SOL_IEEE802154)
 		return -EOPNOTSUPP;

 	if (get_user(len, optlen))
 		return -EFAULT;

 	len = min_t(unsigned int, len, sizeof(int));

 	switch (optname) {
 	case WPAN_WANTACK:
 		val = ro->want_ack;
 		break;
 	default:
 		return -ENOPROTOOPT;
 	}

 	if (put_user(len, optlen))
 		return -EFAULT;
 	if (copy_to_user(optval, &val, len))
 		return -EFAULT;
 	return 0;
 }

 static int dgram_setsockopt(struct sock *sk, int level, int optname,
 		    char __user *optval, unsigned int optlen)
 {
 	struct dgram_sock *ro = dgram_sk(sk);
 	int val;
 	int err = 0;

 	if (optlen < sizeof(int))
 		return -EINVAL;

 	if (get_user(val, (int __user *)optval))
 		return -EFAULT;

 	lock_sock(sk);

 	switch (optname) {
 	case WPAN_WANTACK:
 		ro->want_ack = !!val;
 		break;
 	default:
 		err = -ENOPROTOOPT;
 		break;
 	}

 	release_sock(sk);
 	return err;
 }

 struct proto ieee802154_dgram_prot = {
 	.name		= "IEEE-802.15.4-MAC",
 	.owner		= THIS_MODULE,
 	.obj_size	= sizeof(struct dgram_sock),
 	.init		= dgram_init,
 	.close		= dgram_close,
 	.bind		= dgram_bind,
 	.sendmsg	= dgram_sendmsg,
 	.recvmsg	= dgram_recvmsg,
 	.hash		= dgram_hash,
 	.unhash		= dgram_unhash,
 	.connect	= dgram_connect,
 	.disconnect	= dgram_disconnect,
 	.ioctl		= dgram_ioctl,
 	.getsockopt	= dgram_getsockopt,
 	.setsockopt	= dgram_setsockopt,
 };
	/*
	* ZigBee socket interface
	*
	* Copyright 2007, 2008 Siemens AG
	*
	* 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.
	*
	* You should have received a copy of the GNU General Public License along
	* with this program; if not, write to the Free Software Foundation, Inc.,
	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Written by:
	* Sergey Lapin <slapin@ossfans.org>
	* Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
	*/

	#include <linux/net.h>
	#include <linux/module.h>
	#include <linux/if_arp.h>
	#include <linux/list.h>
	#include <net/sock.h>
	#include <net/af_ieee802154.h>
	#include <net/ieee802154.h>
	#include <net/ieee802154_netdev.h>

	#include <asm/ioctls.h>

	#include "af802154.h"

	static HLIST_HEAD(dgram_head);
	static DEFINE_RWLOCK(dgram_lock);

	struct dgram_sock {
	struct sock sk;

	struct ieee802154_addr src_addr;
	struct ieee802154_addr dst_addr;

	unsigned bound:1;
	unsigned want_ack:1;
	};

	static inline struct dgram_sock dgram_sk(const struct sock sk)
	{
	return container_of(sk, struct dgram_sock, sk);
	}

	static void dgram_hash(struct sock *sk)
	{
	write_lock_bh(&dgram_lock);
	sk_add_node(sk, &dgram_head);
	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
	write_unlock_bh(&dgram_lock);
	}

	static void dgram_unhash(struct sock *sk)
	{
	write_lock_bh(&dgram_lock);
	if (sk_del_node_init(sk))
	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
	write_unlock_bh(&dgram_lock);
	}

	static int dgram_init(struct sock *sk)
	{
	struct dgram_sock *ro = dgram_sk(sk);

	ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
	ro->dst_addr.pan_id = 0xffff;
	ro->want_ack = 1;
	memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));
	return 0;
	}

	static void dgram_close(struct sock *sk, long timeout)
	{
	sk_common_release(sk);
	}

	static int dgram_bind(struct sock sk, struct sockaddr uaddr, int len)
	{
	struct sockaddr_ieee802154 addr = (struct sockaddr_ieee802154 )uaddr;
	struct dgram_sock *ro = dgram_sk(sk);
	int err = -EINVAL;
	struct net_device *dev;

	lock_sock(sk);

	ro->bound = 0;

	if (len < sizeof(*addr))
	goto out;

	if (addr->family != AF_IEEE802154)
	goto out;

	dev = ieee802154_get_dev(sock_net(sk), &addr->addr);
	if (!dev) {
	err = -ENODEV;
	goto out;
	}

	if (dev->type != ARPHRD_IEEE802154) {
	err = -ENODEV;
	goto out_put;
	}

	memcpy(&ro->src_addr, &addr->addr, sizeof(struct ieee802154_addr));

	ro->bound = 1;
	err = 0;
	out_put:
	dev_put(dev);
	out:
	release_sock(sk);

	return err;
	}

	static int dgram_ioctl(struct sock *sk, int cmd, unsigned long arg)
	{
	switch (cmd) {
	case SIOCOUTQ:
	{
	int amount = sk_wmem_alloc_get(sk);

	return put_user(amount, (int __user *)arg);
	}

	case SIOCINQ:
	{
	struct sk_buff *skb;
	unsigned long amount;

	amount = 0;
	spin_lock_bh(&sk->sk_receive_queue.lock);
	skb = skb_peek(&sk->sk_receive_queue);
	if (skb != NULL) {
	/*
	* We will only return the amount
	* of this packet since that is all
	* that will be read.
	*/
	/* FIXME: parse the header for more correct value */
	amount = skb->len - (3+8+8);
	}
	spin_unlock_bh(&sk->sk_receive_queue.lock);
	return put_user(amount, (int __user *)arg);
	}

	}
	return -ENOIOCTLCMD;
	}

	/* FIXME: autobind */
	static int dgram_connect(struct sock sk, struct sockaddr uaddr,
	int len)
	{
	struct sockaddr_ieee802154 addr = (struct sockaddr_ieee802154 )uaddr;
	struct dgram_sock *ro = dgram_sk(sk);
	int err = 0;

	if (len < sizeof(*addr))
	return -EINVAL;

	if (addr->family != AF_IEEE802154)
	return -EINVAL;

	lock_sock(sk);

	if (!ro->bound) {
	err = -ENETUNREACH;
	goto out;
	}

	memcpy(&ro->dst_addr, &addr->addr, sizeof(struct ieee802154_addr));

	out:
	release_sock(sk);
	return err;
	}

	static int dgram_disconnect(struct sock *sk, int flags)
	{
	struct dgram_sock *ro = dgram_sk(sk);

	lock_sock(sk);

	ro->dst_addr.addr_type = IEEE802154_ADDR_LONG;
	memset(&ro->dst_addr.hwaddr, 0xff, sizeof(ro->dst_addr.hwaddr));

	release_sock(sk);

	return 0;
	}

	static int dgram_sendmsg(struct kiocb iocb, struct sock sk,
	struct msghdr *msg, size_t size)
	{
	struct net_device *dev;
	unsigned mtu;
	struct sk_buff *skb;
	struct dgram_sock *ro = dgram_sk(sk);
	int err;

	if (msg->msg_flags & MSG_OOB) {
	pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
	return -EOPNOTSUPP;
	}

	if (!ro->bound)
	dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
	else
	dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);

	if (!dev) {
	pr_debug("no dev\n");
	err = -ENXIO;
	goto out;
	}
	mtu = dev->mtu;
	pr_debug("name = %s, mtu = %u\n", dev->name, mtu);

	skb = sock_alloc_send_skb(sk, LL_ALLOCATED_SPACE(dev) + size,
	msg->msg_flags & MSG_DONTWAIT,
	&err);
	if (!skb)
	goto out_dev;

	skb_reserve(skb, LL_RESERVED_SPACE(dev));

	skb_reset_network_header(skb);

	mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
	if (ro->want_ack)
	mac_cb(skb)->flags \|= MAC_CB_FLAG_ACKREQ;

	mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
	err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &ro->dst_addr,
	ro->bound ? &ro->src_addr : NULL, size);
	if (err < 0)
	goto out_skb;

	skb_reset_mac_header(skb);

	err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
	if (err < 0)
	goto out_skb;

	if (size > mtu) {
	pr_debug("size = %Zu, mtu = %u\n", size, mtu);
	err = -EINVAL;
	goto out_skb;
	}

	skb->dev = dev;
	skb->sk = sk;
	skb->protocol = htons(ETH_P_IEEE802154);

	dev_put(dev);

	err = dev_queue_xmit(skb);
	if (err > 0)
	err = net_xmit_errno(err);

	return err ?: size;

	out_skb:
	kfree_skb(skb);
	out_dev:
	dev_put(dev);
	out:
	return err;
	}

	static int dgram_recvmsg(struct kiocb iocb, struct sock sk,
	struct msghdr *msg, size_t len, int noblock, int flags,
	int *addr_len)
	{
	size_t copied = 0;
	int err = -EOPNOTSUPP;
	struct sk_buff *skb;

	skb = skb_recv_datagram(sk, flags, noblock, &err);
	if (!skb)
	goto out;

	copied = skb->len;
	if (len < copied) {
	msg->msg_flags \|= MSG_TRUNC;
	copied = len;
	}

	/* FIXME: skip headers if necessary ?! */
	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
	goto done;

	sock_recv_ts_and_drops(msg, sk, skb);

	if (flags & MSG_TRUNC)
	copied = skb->len;
	done:
	skb_free_datagram(sk, skb);
	out:
	if (err)
	return err;
	return copied;
	}

	static int dgram_rcv_skb(struct sock sk, struct sk_buff skb)
	{
	if (sock_queue_rcv_skb(sk, skb) < 0) {
	atomic_inc(&sk->sk_drops);
	kfree_skb(skb);
	return NET_RX_DROP;
	}

	return NET_RX_SUCCESS;
	}

	static inline int ieee802154_match_sock(u8 *hw_addr, u16 pan_id,
	u16 short_addr, struct dgram_sock *ro)
	{
	if (!ro->bound)
	return 1;

	if (ro->src_addr.addr_type == IEEE802154_ADDR_LONG &&
	!memcmp(ro->src_addr.hwaddr, hw_addr, IEEE802154_ADDR_LEN))
	return 1;

	if (ro->src_addr.addr_type == IEEE802154_ADDR_SHORT &&
	pan_id == ro->src_addr.pan_id &&
	short_addr == ro->src_addr.short_addr)
	return 1;

	return 0;
	}

	int ieee802154_dgram_deliver(struct net_device dev, struct sk_buff skb)
	{
	struct sock sk, prev = NULL;
	struct hlist_node *node;
	int ret = NET_RX_SUCCESS;
	u16 pan_id, short_addr;

	/* Data frame processing */
	BUG_ON(dev->type != ARPHRD_IEEE802154);

	pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
	short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);

	read_lock(&dgram_lock);
	sk_for_each(sk, node, &dgram_head) {
	if (ieee802154_match_sock(dev->dev_addr, pan_id, short_addr,
	dgram_sk(sk))) {
	if (prev) {
	struct sk_buff *clone;
	clone = skb_clone(skb, GFP_ATOMIC);
	if (clone)
	dgram_rcv_skb(prev, clone);
	}

	prev = sk;
	}
	}

	if (prev)
	dgram_rcv_skb(prev, skb);
	else {
	kfree_skb(skb);
	ret = NET_RX_DROP;
	}
	read_unlock(&dgram_lock);

	return ret;
	}

	static int dgram_getsockopt(struct sock *sk, int level, int optname,
	char __user optval, int __user optlen)
	{
	struct dgram_sock *ro = dgram_sk(sk);

	int val, len;

	if (level != SOL_IEEE802154)
	return -EOPNOTSUPP;

	if (get_user(len, optlen))
	return -EFAULT;

	len = min_t(unsigned int, len, sizeof(int));

	switch (optname) {
	case WPAN_WANTACK:
	val = ro->want_ack;
	break;
	default:
	return -ENOPROTOOPT;
	}

	if (put_user(len, optlen))
	return -EFAULT;
	if (copy_to_user(optval, &val, len))
	return -EFAULT;
	return 0;
	}

	static int dgram_setsockopt(struct sock *sk, int level, int optname,
	char __user *optval, unsigned int optlen)
	{
	struct dgram_sock *ro = dgram_sk(sk);
	int val;
	int err = 0;

	if (optlen < sizeof(int))
	return -EINVAL;

	if (get_user(val, (int __user *)optval))
	return -EFAULT;

	lock_sock(sk);

	switch (optname) {
	case WPAN_WANTACK:
	ro->want_ack = !!val;
	break;
	default:
	err = -ENOPROTOOPT;
	break;
	}

	release_sock(sk);
	return err;
	}

	struct proto ieee802154_dgram_prot = {
	.name = "IEEE-802.15.4-MAC",
	.owner = THIS_MODULE,
	.obj_size = sizeof(struct dgram_sock),
	.init = dgram_init,
	.close = dgram_close,
	.bind = dgram_bind,
	.sendmsg = dgram_sendmsg,
	.recvmsg = dgram_recvmsg,
	.hash = dgram_hash,
	.unhash = dgram_unhash,
	.connect = dgram_connect,
	.disconnect = dgram_disconnect,
	.ioctl = dgram_ioctl,
	.getsockopt = dgram_getsockopt,
	.setsockopt = dgram_setsockopt,
	};