mac802154: add wpan device-class support

Every real 802.15.4 transceiver, which works with software MAC layer,
can be classified as a wpan device in this stack. So the wpan device
implementation provides missing link in datapath between the device
drivers and the Linux network queue.

According to the IEEE 802.15.4 standard each packet can be one of the
following types:
 - beacon
 - MAC layer command
 - ACK
 - data

This patch adds support for the data packet-type only, but this is
enough to perform data transmission and receiving over radio.

Signed-off-by: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 559 insertions, 0 deletions

diff --git a/net/mac802154/wpan.c b/net/mac802154/wpan.c
new file mode 100644
index 0000000..f30f6d4
--- /dev/null
+++ b/net/mac802154/wpan.c
@@ -0,0 +1,559 @@
+/*
+ * Copyright 2007-2012 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:
+ * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
+ * Sergey Lapin <slapin@ossfans.org>
+ * Maxim Gorbachyov <maxim.gorbachev@siemens.com>
+ * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
+ */
+
+#include <linux/netdevice.h>
+#include <linux/module.h>
+#include <linux/if_arp.h>
+
+#include <net/rtnetlink.h>
+#include <linux/nl802154.h>
+#include <net/af_ieee802154.h>
+#include <net/mac802154.h>
+#include <net/ieee802154_netdev.h>
+#include <net/ieee802154.h>
+#include <net/wpan-phy.h>
+
+#include "mac802154.h"
+
+static inline int mac802154_fetch_skb_u8(struct sk_buff *skb, u8 *val)
+{
+	if (unlikely(!pskb_may_pull(skb, 1)))
+		return -EINVAL;
+
+	*val = skb->data[0];
+	 skb_pull(skb, 1);
+
+	return 0;
+}
+
+static inline int mac802154_fetch_skb_u16(struct sk_buff *skb, u16 *val)
+{
+	if (unlikely(!pskb_may_pull(skb, 2)))
+		return -EINVAL;
+
+	*val = skb->data[0] | (skb->data[1] << 8);
+	skb_pull(skb, 2);
+
+	return 0;
+}
+
+static inline void mac802154_haddr_copy_swap(u8 *dest, const u8 *src)
+{
+	int i;
+	for (i = 0; i < IEEE802154_ADDR_LEN; i++)
+		dest[IEEE802154_ADDR_LEN - i - 1] = src[i];
+}
+
+static int
+mac802154_wpan_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	struct mac802154_sub_if_data *priv = netdev_priv(dev);
+	struct sockaddr_ieee802154 *sa =
+		(struct sockaddr_ieee802154 *)&ifr->ifr_addr;
+	int err = -ENOIOCTLCMD;
+
+	spin_lock_bh(&priv->mib_lock);
+
+	switch (cmd) {
+	case SIOCGIFADDR:
+		if (priv->pan_id == IEEE802154_PANID_BROADCAST ||
+		    priv->short_addr == IEEE802154_ADDR_BROADCAST) {
+			err = -EADDRNOTAVAIL;
+			break;
+		}
+
+		sa->family = AF_IEEE802154;
+		sa->addr.addr_type = IEEE802154_ADDR_SHORT;
+		sa->addr.pan_id = priv->pan_id;
+		sa->addr.short_addr = priv->short_addr;
+
+		err = 0;
+		break;
+	case SIOCSIFADDR:
+		dev_warn(&dev->dev,
+			 "Using DEBUGing ioctl SIOCSIFADDR isn't recommened!\n");
+		if (sa->family != AF_IEEE802154 ||
+		    sa->addr.addr_type != IEEE802154_ADDR_SHORT ||
+		    sa->addr.pan_id == IEEE802154_PANID_BROADCAST ||
+		    sa->addr.short_addr == IEEE802154_ADDR_BROADCAST ||
+		    sa->addr.short_addr == IEEE802154_ADDR_UNDEF) {
+			err = -EINVAL;
+			break;
+		}
+
+		priv->pan_id = sa->addr.pan_id;
+		priv->short_addr = sa->addr.short_addr;
+
+		err = 0;
+		break;
+	}
+
+	spin_unlock_bh(&priv->mib_lock);
+	return err;
+}
+
+static int mac802154_wpan_mac_addr(struct net_device *dev, void *p)
+{
+	struct sockaddr *addr = p;
+
+	if (netif_running(dev))
+		return -EBUSY;
+
+	/* FIXME: validate addr */
+	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
+	mac802154_dev_set_ieee_addr(dev);
+	return 0;
+}
+
+static int mac802154_header_create(struct sk_buff *skb,
+				   struct net_device *dev,
+				   unsigned short type,
+				   const void *_daddr,
+				   const void *_saddr,
+				   unsigned len)
+{
+	const struct ieee802154_addr *saddr = _saddr;
+	const struct ieee802154_addr *daddr = _daddr;
+	struct ieee802154_addr dev_addr;
+	struct mac802154_sub_if_data *priv = netdev_priv(dev);
+	int pos = 2;
+	u8 *head;
+	u16 fc;
+
+	if (!daddr)
+		return -EINVAL;
+
+	head = kzalloc(MAC802154_FRAME_HARD_HEADER_LEN, GFP_KERNEL);
+	if (head == NULL)
+		return -ENOMEM;
+
+	head[pos++] = mac_cb(skb)->seq; /* DSN/BSN */
+	fc = mac_cb_type(skb);
+
+	if (!saddr) {
+		spin_lock_bh(&priv->mib_lock);
+
+		if (priv->short_addr == IEEE802154_ADDR_BROADCAST ||
+		    priv->short_addr == IEEE802154_ADDR_UNDEF ||
+		    priv->pan_id == IEEE802154_PANID_BROADCAST) {
+			dev_addr.addr_type = IEEE802154_ADDR_LONG;
+			memcpy(dev_addr.hwaddr, dev->dev_addr,
+			       IEEE802154_ADDR_LEN);
+		} else {
+			dev_addr.addr_type = IEEE802154_ADDR_SHORT;
+			dev_addr.short_addr = priv->short_addr;
+		}
+
+		dev_addr.pan_id = priv->pan_id;
+		saddr = &dev_addr;
+
+		spin_unlock_bh(&priv->mib_lock);
+	}
+
+	if (daddr->addr_type != IEEE802154_ADDR_NONE) {
+		fc |= (daddr->addr_type << IEEE802154_FC_DAMODE_SHIFT);
+
+		head[pos++] = daddr->pan_id & 0xff;
+		head[pos++] = daddr->pan_id >> 8;
+
+		if (daddr->addr_type == IEEE802154_ADDR_SHORT) {
+			head[pos++] = daddr->short_addr & 0xff;
+			head[pos++] = daddr->short_addr >> 8;
+		} else {
+			mac802154_haddr_copy_swap(head + pos, daddr->hwaddr);
+			pos += IEEE802154_ADDR_LEN;
+		}
+	}
+
+	if (saddr->addr_type != IEEE802154_ADDR_NONE) {
+		fc |= (saddr->addr_type << IEEE802154_FC_SAMODE_SHIFT);
+
+		if ((saddr->pan_id == daddr->pan_id) &&
+		    (saddr->pan_id != IEEE802154_PANID_BROADCAST)) {
+			/* PANID compression/intra PAN */
+			fc |= IEEE802154_FC_INTRA_PAN;
+		} else {
+			head[pos++] = saddr->pan_id & 0xff;
+			head[pos++] = saddr->pan_id >> 8;
+		}
+
+		if (saddr->addr_type == IEEE802154_ADDR_SHORT) {
+			head[pos++] = saddr->short_addr & 0xff;
+			head[pos++] = saddr->short_addr >> 8;
+		} else {
+			mac802154_haddr_copy_swap(head + pos, saddr->hwaddr);
+			pos += IEEE802154_ADDR_LEN;
+		}
+	}
+
+	head[0] = fc;
+	head[1] = fc >> 8;
+
+	memcpy(skb_push(skb, pos), head, pos);
+	kfree(head);
+
+	return pos;
+}
+
+static int
+mac802154_header_parse(const struct sk_buff *skb, unsigned char *haddr)
+{
+	const u8 *hdr = skb_mac_header(skb);
+	const u8 *tail = skb_tail_pointer(skb);
+	struct ieee802154_addr *addr = (struct ieee802154_addr *)haddr;
+	u16 fc;
+	int da_type;
+
+	if (hdr + 3 > tail)
+		goto malformed;
+
+	fc = hdr[0] | (hdr[1] << 8);
+
+	hdr += 3;
+
+	da_type = IEEE802154_FC_DAMODE(fc);
+	addr->addr_type = IEEE802154_FC_SAMODE(fc);
+
+	switch (da_type) {
+	case IEEE802154_ADDR_NONE:
+		if (fc & IEEE802154_FC_INTRA_PAN)
+			goto malformed;
+		break;
+	case IEEE802154_ADDR_LONG:
+		if (fc & IEEE802154_FC_INTRA_PAN) {
+			if (hdr + 2 > tail)
+				goto malformed;
+			addr->pan_id = hdr[0] | (hdr[1] << 8);
+			hdr += 2;
+		}
+
+		if (hdr + IEEE802154_ADDR_LEN > tail)
+			goto malformed;
+
+		hdr += IEEE802154_ADDR_LEN;
+		break;
+	case IEEE802154_ADDR_SHORT:
+		if (fc & IEEE802154_FC_INTRA_PAN) {
+			if (hdr + 2 > tail)
+				goto malformed;
+			addr->pan_id = hdr[0] | (hdr[1] << 8);
+			hdr += 2;
+		}
+
+		if (hdr + 2 > tail)
+			goto malformed;
+
+		hdr += 2;
+		break;
+	default:
+		goto malformed;
+
+	}
+
+	switch (addr->addr_type) {
+	case IEEE802154_ADDR_NONE:
+		break;
+	case IEEE802154_ADDR_LONG:
+		if (!(fc & IEEE802154_FC_INTRA_PAN)) {
+			if (hdr + 2 > tail)
+				goto malformed;
+			addr->pan_id = hdr[0] | (hdr[1] << 8);
+			hdr += 2;
+		}
+
+		if (hdr + IEEE802154_ADDR_LEN > tail)
+			goto malformed;
+
+		mac802154_haddr_copy_swap(addr->hwaddr, hdr);
+		hdr += IEEE802154_ADDR_LEN;
+		break;
+	case IEEE802154_ADDR_SHORT:
+		if (!(fc & IEEE802154_FC_INTRA_PAN)) {
+			if (hdr + 2 > tail)
+				goto malformed;
+			addr->pan_id = hdr[0] | (hdr[1] << 8);
+			hdr += 2;
+		}
+
+		if (hdr + 2 > tail)
+			goto malformed;
+
+		addr->short_addr = hdr[0] | (hdr[1] << 8);
+		hdr += 2;
+		break;
+	default:
+		goto malformed;
+	}
+
+	return sizeof(struct ieee802154_addr);
+
+malformed:
+	pr_debug("malformed packet\n");
+	return 0;
+}
+
+static netdev_tx_t
+mac802154_wpan_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct mac802154_sub_if_data *priv;
+	u8 chan, page;
+
+	priv = netdev_priv(dev);
+
+	spin_lock_bh(&priv->mib_lock);
+	chan = priv->chan;
+	page = priv->page;
+	spin_unlock_bh(&priv->mib_lock);
+
+	if (chan == MAC802154_CHAN_NONE ||
+	    page >= WPAN_NUM_PAGES ||
+	    chan >= WPAN_NUM_CHANNELS)
+		return NETDEV_TX_OK;
+
+	skb->skb_iif = dev->ifindex;
+	dev->stats.tx_packets++;
+	dev->stats.tx_bytes += skb->len;
+
+	return mac802154_tx(priv->hw, skb, page, chan);
+}
+
+static struct header_ops mac802154_header_ops = {
+	.create		= mac802154_header_create,
+	.parse		= mac802154_header_parse,
+};
+
+static const struct net_device_ops mac802154_wpan_ops = {
+	.ndo_open		= mac802154_slave_open,
+	.ndo_stop		= mac802154_slave_close,
+	.ndo_start_xmit		= mac802154_wpan_xmit,
+	.ndo_do_ioctl		= mac802154_wpan_ioctl,
+	.ndo_set_mac_address	= mac802154_wpan_mac_addr,
+};
+
+void mac802154_wpan_setup(struct net_device *dev)
+{
+	struct mac802154_sub_if_data *priv;
+
+	dev->addr_len		= IEEE802154_ADDR_LEN;
+	memset(dev->broadcast, 0xff, IEEE802154_ADDR_LEN);
+
+	dev->hard_header_len	= MAC802154_FRAME_HARD_HEADER_LEN;
+	dev->header_ops		= &mac802154_header_ops;
+	dev->needed_tailroom	= 2; /* FCS */
+	dev->mtu		= IEEE802154_MTU;
+	dev->tx_queue_len	= 10;
+	dev->type		= ARPHRD_IEEE802154;
+	dev->flags		= IFF_NOARP | IFF_BROADCAST;
+	dev->watchdog_timeo	= 0;
+
+	dev->destructor		= free_netdev;
+	dev->netdev_ops		= &mac802154_wpan_ops;
+	dev->ml_priv		= &mac802154_mlme_wpan;
+
+	priv = netdev_priv(dev);
+	priv->type = IEEE802154_DEV_WPAN;
+
+	priv->chan = MAC802154_CHAN_NONE;
+	priv->page = 0;
+
+	spin_lock_init(&priv->mib_lock);
+
+	get_random_bytes(&priv->bsn, 1);
+	get_random_bytes(&priv->dsn, 1);
+
+	priv->pan_id = IEEE802154_PANID_BROADCAST;
+	priv->short_addr = IEEE802154_ADDR_BROADCAST;
+}
+
+static int mac802154_process_data(struct net_device *dev, struct sk_buff *skb)
+{
+	return netif_rx(skb);
+}
+
+static int
+mac802154_subif_frame(struct mac802154_sub_if_data *sdata, struct sk_buff *skb)
+{
+	pr_debug("getting packet via slave interface %s\n", sdata->dev->name);
+
+	spin_lock_bh(&sdata->mib_lock);
+
+	switch (mac_cb(skb)->da.addr_type) {
+	case IEEE802154_ADDR_NONE:
+		if (mac_cb(skb)->sa.addr_type != IEEE802154_ADDR_NONE)
+			/* FIXME: check if we are PAN coordinator */
+			skb->pkt_type = PACKET_OTHERHOST;
+		else
+			/* ACK comes with both addresses empty */
+			skb->pkt_type = PACKET_HOST;
+		break;
+	case IEEE802154_ADDR_LONG:
+		if (mac_cb(skb)->da.pan_id != sdata->pan_id &&
+		    mac_cb(skb)->da.pan_id != IEEE802154_PANID_BROADCAST)
+			skb->pkt_type = PACKET_OTHERHOST;
+		else if (!memcmp(mac_cb(skb)->da.hwaddr, sdata->dev->dev_addr,
+				 IEEE802154_ADDR_LEN))
+			skb->pkt_type = PACKET_HOST;
+		else
+			skb->pkt_type = PACKET_OTHERHOST;
+		break;
+	case IEEE802154_ADDR_SHORT:
+		if (mac_cb(skb)->da.pan_id != sdata->pan_id &&
+		    mac_cb(skb)->da.pan_id != IEEE802154_PANID_BROADCAST)
+			skb->pkt_type = PACKET_OTHERHOST;
+		else if (mac_cb(skb)->da.short_addr == sdata->short_addr)
+			skb->pkt_type = PACKET_HOST;
+		else if (mac_cb(skb)->da.short_addr ==
+					IEEE802154_ADDR_BROADCAST)
+			skb->pkt_type = PACKET_BROADCAST;
+		else
+			skb->pkt_type = PACKET_OTHERHOST;
+		break;
+	default:
+		break;
+	}
+
+	spin_unlock_bh(&sdata->mib_lock);
+
+	skb->dev = sdata->dev;
+
+	sdata->dev->stats.rx_packets++;
+	sdata->dev->stats.rx_bytes += skb->len;
+
+	switch (mac_cb_type(skb)) {
+	case IEEE802154_FC_TYPE_DATA:
+		return mac802154_process_data(sdata->dev, skb);
+	default:
+		pr_warning("ieee802154: bad frame received (type = %d)\n",
+			   mac_cb_type(skb));
+		kfree_skb(skb);
+		return NET_RX_DROP;
+	}
+}
+
+static int mac802154_parse_frame_start(struct sk_buff *skb)
+{
+	u8 *head = skb->data;
+	u16 fc;
+
+	if (mac802154_fetch_skb_u16(skb, &fc) ||
+	    mac802154_fetch_skb_u8(skb, &(mac_cb(skb)->seq)))
+		goto err;
+
+	pr_debug("fc: %04x dsn: %02x\n", fc, head[2]);
+
+	mac_cb(skb)->flags = IEEE802154_FC_TYPE(fc);
+	mac_cb(skb)->sa.addr_type = IEEE802154_FC_SAMODE(fc);
+	mac_cb(skb)->da.addr_type = IEEE802154_FC_DAMODE(fc);
+
+	if (fc & IEEE802154_FC_INTRA_PAN)
+		mac_cb(skb)->flags |= MAC_CB_FLAG_INTRAPAN;
+
+	if (mac_cb(skb)->da.addr_type != IEEE802154_ADDR_NONE) {
+		if (mac802154_fetch_skb_u16(skb, &(mac_cb(skb)->da.pan_id)))
+			goto err;
+
+		/* source PAN id compression */
+		if (mac_cb_is_intrapan(skb))
+			mac_cb(skb)->sa.pan_id = mac_cb(skb)->da.pan_id;
+
+		pr_debug("dest PAN addr: %04x\n", mac_cb(skb)->da.pan_id);
+
+		if (mac_cb(skb)->da.addr_type == IEEE802154_ADDR_SHORT) {
+			u16 *da = &(mac_cb(skb)->da.short_addr);
+
+			if (mac802154_fetch_skb_u16(skb, da))
+				goto err;
+
+			pr_debug("destination address is short: %04x\n",
+				 mac_cb(skb)->da.short_addr);
+		} else {
+			if (!pskb_may_pull(skb, IEEE802154_ADDR_LEN))
+				goto err;
+
+			mac802154_haddr_copy_swap(mac_cb(skb)->da.hwaddr,
+						  skb->data);
+			skb_pull(skb, IEEE802154_ADDR_LEN);
+
+			pr_debug("destination address is hardware\n");
+		}
+	}
+
+	if (mac_cb(skb)->sa.addr_type != IEEE802154_ADDR_NONE) {
+		/* non PAN-compression, fetch source address id */
+		if (!(mac_cb_is_intrapan(skb))) {
+			u16 *sa_pan = &(mac_cb(skb)->sa.pan_id);
+
+			if (mac802154_fetch_skb_u16(skb, sa_pan))
+				goto err;
+		}
+
+		pr_debug("source PAN addr: %04x\n", mac_cb(skb)->da.pan_id);
+
+		if (mac_cb(skb)->sa.addr_type == IEEE802154_ADDR_SHORT) {
+			u16 *sa = &(mac_cb(skb)->sa.short_addr);
+
+			if (mac802154_fetch_skb_u16(skb, sa))
+				goto err;
+
+			pr_debug("source address is short: %04x\n",
+				 mac_cb(skb)->sa.short_addr);
+		} else {
+			if (!pskb_may_pull(skb, IEEE802154_ADDR_LEN))
+				goto err;
+
+			mac802154_haddr_copy_swap(mac_cb(skb)->sa.hwaddr,
+						  skb->data);
+			skb_pull(skb, IEEE802154_ADDR_LEN);
+
+			pr_debug("source address is hardware\n");
+		}
+	}
+
+	return 0;
+err:
+	return -EINVAL;
+}
+
+void mac802154_wpans_rx(struct mac802154_priv *priv, struct sk_buff *skb)
+{
+	int ret;
+	struct sk_buff *sskb;
+	struct mac802154_sub_if_data *sdata;
+
+	ret = mac802154_parse_frame_start(skb);
+	if (ret) {
+		pr_debug("got invalid frame\n");
+		return;
+	}
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(sdata, &priv->slaves, list) {
+		if (sdata->type != IEEE802154_DEV_WPAN)
+			continue;
+
+		sskb = skb_clone(skb, GFP_ATOMIC);
+		if (sskb)
+			mac802154_subif_frame(sdata, sskb);
+	}
+	rcu_read_unlock();
+}