net: add IEEE 802.15.4 socket family implementation

Add support for communication over IEEE 802.15.4 networks. This implementation
is neither certified nor complete, but aims to that goal. This commit contains
only the socket interface for communication over IEEE 802.15.4 networks.
One can either send RAW datagrams or use SOCK_DGRAM to encapsulate data
inside normal IEEE 802.15.4 packets.

Configuration interface, drivers and software MAC 802.15.4 implementation will
follow.

Initial implementation was done by Maxim Gorbachyov, Maxim Osipov and Pavel
Smolensky as a research project at Siemens AG. Later the stack was heavily
reworked to better suit the linux networking model, and is now maitained
as an open project partially sponsored by Siemens.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Sergey Lapin <slapin@ossfans.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 254 insertions, 0 deletions

diff --git a/net/ieee802154/raw.c b/net/ieee802154/raw.c
new file mode 100644
index 00000000000..8b892e06049
--- /dev/null
+++ b/net/ieee802154/raw.c
@@ -0,0 +1,254 @@
+/*
+ * Raw IEEE 802.15.4 sockets
+ *
+ * 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/ieee802154/af_ieee802154.h>
+
+#include "af802154.h"
+
+static HLIST_HEAD(raw_head);
+static DEFINE_RWLOCK(raw_lock);
+
+static void raw_hash(struct sock *sk)
+{
+	write_lock_bh(&raw_lock);
+	sk_add_node(sk, &raw_head);
+	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
+	write_unlock_bh(&raw_lock);
+}
+
+static void raw_unhash(struct sock *sk)
+{
+	write_lock_bh(&raw_lock);
+	if (sk_del_node_init(sk))
+		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
+	write_unlock_bh(&raw_lock);
+}
+
+static void raw_close(struct sock *sk, long timeout)
+{
+	sk_common_release(sk);
+}
+
+static int raw_bind(struct sock *sk, struct sockaddr *uaddr, int len)
+{
+	struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
+	int err = 0;
+	struct net_device *dev = NULL;
+
+	if (len < sizeof(*addr))
+		return -EINVAL;
+
+	if (addr->family != AF_IEEE802154)
+		return -EINVAL;
+
+	lock_sock(sk);
+
+	dev = ieee802154_get_dev(sock_net(sk), &addr->addr);
+	if (!dev) {
+		err = -ENODEV;
+		goto out;
+	}
+
+	if (dev->type != ARPHRD_IEEE802154_PHY &&
+	    dev->type != ARPHRD_IEEE802154) {
+		err = -ENODEV;
+		goto out_put;
+	}
+
+	sk->sk_bound_dev_if = dev->ifindex;
+	sk_dst_reset(sk);
+
+out_put:
+	dev_put(dev);
+out:
+	release_sock(sk);
+
+	return err;
+}
+
+static int raw_connect(struct sock *sk, struct sockaddr *uaddr,
+			int addr_len)
+{
+	return -ENOTSUPP;
+}
+
+static int raw_disconnect(struct sock *sk, int flags)
+{
+	return 0;
+}
+
+static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
+		       size_t size)
+{
+	struct net_device *dev;
+	unsigned mtu;
+	struct sk_buff *skb;
+	int err;
+
+	if (msg->msg_flags & MSG_OOB) {
+		pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
+		return -EOPNOTSUPP;
+	}
+
+	lock_sock(sk);
+	if (!sk->sk_bound_dev_if)
+		dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
+	else
+		dev = dev_get_by_index(sock_net(sk), sk->sk_bound_dev_if);
+	release_sock(sk);
+
+	if (!dev) {
+		pr_debug("no dev\n");
+		err = -ENXIO;
+		goto out;
+	}
+
+	mtu = dev->mtu;
+	pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
+
+	if (size > mtu) {
+		pr_debug("size = %u, mtu = %u\n", size, mtu);
+		err = -EINVAL;
+		goto out_dev;
+	}
+
+	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_mac_header(skb);
+	skb_reset_network_header(skb);
+
+	err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
+	if (err < 0)
+		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 raw_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;
+	}
+
+	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
+	if (err)
+		goto done;
+
+	sock_recv_timestamp(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 raw_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;
+}
+
+
+void ieee802154_raw_deliver(struct net_device *dev, struct sk_buff *skb)
+{
+	struct sock *sk;
+	struct hlist_node *node;
+
+	read_lock(&raw_lock);
+	sk_for_each(sk, node, &raw_head) {
+		bh_lock_sock(sk);
+		if (!sk->sk_bound_dev_if ||
+		    sk->sk_bound_dev_if == dev->ifindex) {
+
+			struct sk_buff *clone;
+
+			clone = skb_clone(skb, GFP_ATOMIC);
+			if (clone)
+				raw_rcv_skb(sk, clone);
+		}
+		bh_unlock_sock(sk);
+	}
+	read_unlock(&raw_lock);
+}
+
+struct proto ieee802154_raw_prot = {
+	.name		= "IEEE-802.15.4-RAW",
+	.owner		= THIS_MODULE,
+	.obj_size	= sizeof(struct sock),
+	.close		= raw_close,
+	.bind		= raw_bind,
+	.sendmsg	= raw_sendmsg,
+	.recvmsg	= raw_recvmsg,
+	.hash		= raw_hash,
+	.unhash		= raw_unhash,
+	.connect	= raw_connect,
+	.disconnect	= raw_disconnect,
+};
+