summaryrefslogtreecommitdiffstats
path: root/net/mac802154
diff options
context:
space:
mode:
Diffstat (limited to 'net/mac802154')
-rw-r--r--net/mac802154/Makefile2
-rw-r--r--net/mac802154/ieee802154_dev.c4
-rw-r--r--net/mac802154/mac802154.h4
-rw-r--r--net/mac802154/mac_cmd.c4
-rw-r--r--net/mac802154/rx.c1
-rw-r--r--net/mac802154/wpan.c559
6 files changed, 573 insertions, 1 deletions
diff --git a/net/mac802154/Makefile b/net/mac802154/Makefile
index ec1bd3f..57cf5d1 100644
--- a/net/mac802154/Makefile
+++ b/net/mac802154/Makefile
@@ -1,2 +1,2 @@
obj-$(CONFIG_MAC802154) += mac802154.o
-mac802154-objs := ieee802154_dev.o rx.o tx.o mac_cmd.o mib.o monitor.o
+mac802154-objs := ieee802154_dev.o rx.o tx.o mac_cmd.o mib.o monitor.o wpan.o
diff --git a/net/mac802154/ieee802154_dev.c b/net/mac802154/ieee802154_dev.c
index e3edfb0..e748aed 100644
--- a/net/mac802154/ieee802154_dev.c
+++ b/net/mac802154/ieee802154_dev.c
@@ -140,6 +140,10 @@ mac802154_add_iface(struct wpan_phy *phy, const char *name, int type)
dev = alloc_netdev(sizeof(struct mac802154_sub_if_data),
name, mac802154_monitor_setup);
break;
+ case IEEE802154_DEV_WPAN:
+ dev = alloc_netdev(sizeof(struct mac802154_sub_if_data),
+ name, mac802154_wpan_setup);
+ break;
default:
dev = NULL;
err = -EINVAL;
diff --git a/net/mac802154/mac802154.h b/net/mac802154/mac802154.h
index 789d9c9..c0efcf1 100644
--- a/net/mac802154/mac802154.h
+++ b/net/mac802154/mac802154.h
@@ -93,6 +93,7 @@ struct mac802154_sub_if_data {
#define MAC802154_CHAN_NONE (~(u8)0) /* No channel is assigned */
extern struct ieee802154_reduced_mlme_ops mac802154_mlme_reduced;
+extern struct ieee802154_mlme_ops mac802154_mlme_wpan;
int mac802154_slave_open(struct net_device *dev);
int mac802154_slave_close(struct net_device *dev);
@@ -100,6 +101,9 @@ int mac802154_slave_close(struct net_device *dev);
void mac802154_monitors_rx(struct mac802154_priv *priv, struct sk_buff *skb);
void mac802154_monitor_setup(struct net_device *dev);
+void mac802154_wpans_rx(struct mac802154_priv *priv, struct sk_buff *skb);
+void mac802154_wpan_setup(struct net_device *dev);
+
netdev_tx_t mac802154_tx(struct mac802154_priv *priv, struct sk_buff *skb,
u8 page, u8 chan);
diff --git a/net/mac802154/mac_cmd.c b/net/mac802154/mac_cmd.c
index 7a5d0e0..db83419 100644
--- a/net/mac802154/mac_cmd.c
+++ b/net/mac802154/mac_cmd.c
@@ -43,3 +43,7 @@ struct wpan_phy *mac802154_get_phy(const struct net_device *dev)
struct ieee802154_reduced_mlme_ops mac802154_mlme_reduced = {
.get_phy = mac802154_get_phy,
};
+
+struct ieee802154_mlme_ops mac802154_mlme_wpan = {
+ .get_phy = mac802154_get_phy,
+};
diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c
index 4a7d76d..38548ec 100644
--- a/net/mac802154/rx.c
+++ b/net/mac802154/rx.c
@@ -77,6 +77,7 @@ mac802154_subif_rx(struct ieee802154_dev *hw, struct sk_buff *skb, u8 lqi)
}
mac802154_monitors_rx(priv, skb);
+ mac802154_wpans_rx(priv, skb);
out:
dev_kfree_skb(skb);
return;
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();
+}
OpenPOWER on IntegriCloud