* [RFC v4 3/6] Bluetooth: Initial skeleton code for BT 6LoWPAN
2013-11-13 10:11 [RFC v4 0/6] Bluetooth LE 6LoWPAN Jukka Rissanen
2013-11-13 10:11 ` [RFC v4 1/6] net: if_arp: add ARPHRD_RAWIP type Jukka Rissanen
2013-11-13 10:11 ` [RFC v4 2/6] ipv6: Add checks for RAWIP ARP type Jukka Rissanen
@ 2013-11-13 10:11 ` Jukka Rissanen
2013-11-14 7:58 ` Marcel Holtmann
2013-11-13 10:11 ` [RFC v4 4/6] Bluetooth: Enable 6LoWPAN support for BT LE devices Jukka Rissanen
` (2 subsequent siblings)
5 siblings, 1 reply; 9+ messages in thread
From: Jukka Rissanen @ 2013-11-13 10:11 UTC (permalink / raw)
To: linux-bluetooth
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
---
include/net/bluetooth/l2cap.h | 1 +
net/bluetooth/6lowpan.c | 544 ++++++++++++++++++++++++++++++++++++++++++
net/bluetooth/6lowpan.h | 26 ++
net/bluetooth/Makefile | 2 +-
net/bluetooth/l2cap_core.c | 22 +-
5 files changed, 593 insertions(+), 2 deletions(-)
create mode 100644 net/bluetooth/6lowpan.c
create mode 100644 net/bluetooth/6lowpan.h
diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 5132990..c28ac0d 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -133,6 +133,7 @@ struct l2cap_conninfo {
#define L2CAP_FC_L2CAP 0x02
#define L2CAP_FC_CONNLESS 0x04
#define L2CAP_FC_A2MP 0x08
+#define L2CAP_FC_6LOWPAN 0x3e
/* L2CAP Control Field bit masks */
#define L2CAP_CTRL_SAR 0xC000
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
new file mode 100644
index 0000000..85754e2
--- /dev/null
+++ b/net/bluetooth/6lowpan.c
@@ -0,0 +1,544 @@
+/*
+ Copyright (c) 2013 Intel Corp.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License version 2 and
+ only 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.
+*/
+
+#include <linux/version.h>
+#include <linux/bitops.h>
+#include <linux/if_arp.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+
+#include <net/ipv6.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+
+#include <net/af_ieee802154.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/l2cap.h>
+
+#include "../ieee802154/6lowpan.h" /* for the compression defines */
+
+#define IFACE_NAME_TEMPLATE "bt%d"
+#define EUI64_ADDR_LEN 8
+
+struct skb_cb {
+ struct in6_addr addr;
+ struct l2cap_conn *conn;
+};
+#define lowpan_cb(skb) ((struct skb_cb *)((skb)->cb))
+
+/*
+ * The devices list contains those devices that we are acting
+ * as a proxy. The BT 6LoWPAN device is a virtual device that
+ * connects to the Bluetooth LE device. The real connection to
+ * BT device is done via l2cap layer. There exists one
+ * virtual device / one BT 6LoWPAN network (=hciX device).
+ * The list contains struct lowpan_dev elements.
+ */
+static LIST_HEAD(bt_6lowpan_devices);
+static DEFINE_RWLOCK(devices_lock);
+
+struct lowpan_dev {
+ struct net_device *dev;
+ struct work_struct delete_netdev;
+ struct list_head list;
+};
+
+struct peer {
+ struct list_head list;
+ struct l2cap_conn *conn;
+
+ /* peer addresses in various formats */
+ unsigned char eui64_addr[EUI64_ADDR_LEN];
+ struct in6_addr peer_addr;
+};
+
+struct lowpan_info {
+ struct net_device *net;
+ struct list_head peers;
+ int peer_count;
+};
+
+static inline struct lowpan_info *lowpan_info(const struct net_device *dev)
+{
+ return netdev_priv(dev);
+}
+
+static inline void peer_add(struct lowpan_info *info, struct peer *peer)
+{
+ list_add(&peer->list, &info->peers);
+ info->peer_count++;
+}
+
+static inline void peer_del(struct lowpan_info *info, struct peer *peer)
+{
+ list_del(&peer->list);
+ info->peer_count--;
+ if (info->peer_count < 0) {
+ BT_ERR("peer count underflow");
+ info->peer_count = 0;
+ }
+}
+
+static inline struct peer *peer_lookup_ba(struct lowpan_info *info,
+ __u8 type, bdaddr_t *ba)
+{
+ struct peer *peer, *tmp;
+
+ BT_DBG("peers %d addr %pMR type %d", info->peer_count, ba, type);
+
+ list_for_each_entry_safe(peer, tmp, &info->peers, list) {
+ BT_DBG("addr %pMR type %d",
+ &peer->conn->hcon->dst, peer->conn->hcon->dst_type);
+
+ if (!bacmp(&peer->conn->hcon->dst, ba))
+ return peer;
+ }
+
+ return NULL;
+}
+
+static inline struct peer *peer_lookup_conn(struct lowpan_info *info,
+ struct l2cap_conn *conn)
+{
+ struct peer *peer, *tmp;
+
+ list_for_each_entry_safe(peer, tmp, &info->peers, list) {
+ if (peer->conn == conn)
+ return peer;
+ }
+
+ return NULL;
+}
+
+static struct peer *lookup_peer(struct l2cap_conn *conn,
+ struct lowpan_info **dev)
+{
+ struct lowpan_dev *entry, *tmp;
+ struct peer *peer = NULL;
+
+ write_lock(&devices_lock);
+
+ list_for_each_entry_safe(entry, tmp, &bt_6lowpan_devices, list) {
+ struct lowpan_info *info = lowpan_info(entry->dev);
+
+ if (dev)
+ *dev = info;
+
+ peer = peer_lookup_conn(info, conn);
+ if (peer)
+ break;
+ }
+
+ write_unlock(&devices_lock);
+
+ return peer;
+}
+
+/* print data in line */
+static inline void raw_dump_inline(const char *caller, char *msg,
+ unsigned char *buf, int len)
+{
+ if (msg)
+ pr_debug("%s():%s: ", caller, msg);
+ print_hex_dump_debug("", DUMP_PREFIX_NONE,
+ 16, 1, buf, len, false);
+}
+
+/*
+ * print data in a table format:
+ *
+ * addr: xx xx xx xx xx xx
+ * addr: xx xx xx xx xx xx
+ * ...
+ */
+static inline void raw_dump_table(const char *caller, char *msg,
+ unsigned char *buf, int len)
+{
+ if (msg)
+ pr_debug("%s():%s:\n", caller, msg);
+ print_hex_dump_debug("\t", DUMP_PREFIX_OFFSET,
+ 16, 1, buf, len, false);
+}
+
+static int recv_pkt(struct sk_buff *skb, struct net_device *dev)
+{
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
+
+/* Packet from BT LE device */
+int bt_6lowpan_recv(struct l2cap_conn *conn, struct sk_buff *skb)
+{
+ struct lowpan_info *info = NULL;
+ struct peer *peer;
+ int err = -ENOENT;
+
+ peer = lookup_peer(conn, &info);
+ if (!peer)
+ return -ENOENT;
+
+ if (info && info->net) {
+ err = recv_pkt(skb, info->net, conn);
+ BT_DBG("recv pkt %d", err);
+ }
+
+ return err;
+}
+
+static void do_send(struct l2cap_conn *conn, struct sk_buff *skb)
+{
+ BT_DBG("conn %p, skb %p len %d priority %u", conn, skb, skb->len,
+ skb->priority);
+
+ return;
+}
+
+static int conn_send(struct l2cap_conn *conn,
+ void *msg, size_t len, u32 priority,
+ struct net_device *dev)
+{
+ struct sk_buff *skb = {0};
+
+ do_send(conn, skb);
+ return 0;
+}
+
+/* Packet to BT LE device */
+static int send_pkt(struct l2cap_conn *conn, const void *saddr,
+ const void *daddr, struct sk_buff *skb,
+ struct net_device *dev)
+{
+ raw_dump_table(__func__, "raw skb data dump before fragmentation",
+ skb->data, skb->len);
+
+ return conn_send(conn, skb->data, skb->len, 0, dev);
+}
+
+static int send_mcast_pkt(struct sk_buff *skb, struct net_device *dev)
+{
+ struct sk_buff *local_skb;
+ struct lowpan_dev *entry, *tmp;
+ int err = 0;
+
+ write_lock(&devices_lock);
+
+ list_for_each_entry_safe(entry, tmp, &bt_6lowpan_devices, list) {
+ struct peer *pentry, *ptmp;
+ struct lowpan_info *info;
+
+ if (entry->dev != dev)
+ continue;
+
+ info = lowpan_info(entry->dev);
+
+ list_for_each_entry_safe(pentry, ptmp, &info->peers, list) {
+ local_skb = skb_clone(skb, GFP_ATOMIC);
+
+ err = send_pkt(pentry->conn, dev->dev_addr,
+ pentry->eui64_addr,
+ local_skb, dev);
+
+ kfree_skb(local_skb);
+ }
+ }
+
+ write_unlock(&devices_lock);
+
+ return err;
+}
+
+static netdev_tx_t xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ int err = -ENOENT;
+ unsigned char *eui64_addr;
+ struct lowpan_info *info;
+ struct peer *peer;
+ bdaddr_t addr;
+ u8 addr_type;
+
+ if (ipv6_addr_is_multicast(&lowpan_cb(skb)->addr)) {
+ /*
+ * We need to send the packet to every device
+ * behind this interface.
+ */
+ err = send_mcast_pkt(skb, dev);
+ } else {
+ get_dest_bdaddr(&lowpan_cb(skb)->addr, &addr, &addr_type);
+ eui64_addr = lowpan_cb(skb)->addr.s6_addr + 8;
+ info = lowpan_info(dev);
+
+ write_lock(&devices_lock);
+ peer = peer_lookup_ba(info, addr_type, &addr);
+ write_unlock(&devices_lock);
+
+ BT_DBG("xmit from %s to %pMR (%pI6c), peer %p", dev->name,
+ &addr, &lowpan_cb(skb)->addr, peer);
+
+ if (peer && peer->conn)
+ err = send_pkt(peer->conn,
+ dev->dev_addr,
+ eui64_addr,
+ skb,
+ dev);
+ }
+ dev_kfree_skb(skb);
+
+ if (err)
+ BT_DBG("ERROR: xmit failed (%d)", err);
+
+ return (err < 0) ? NET_XMIT_DROP : err;
+}
+
+static const struct net_device_ops netdev_ops = {
+ .ndo_start_xmit = xmit,
+};
+
+static void netdev_setup(struct net_device *dev)
+{
+ dev->addr_len = EUI64_ADDR_LEN;
+ dev->type = ARPHRD_RAWIP;
+
+ dev->hard_header_len = 0;
+ dev->needed_tailroom = 0;
+ dev->mtu = IPV6_MIN_MTU;
+ dev->tx_queue_len = 0;
+ dev->flags = IFF_RUNNING | IFF_POINTOPOINT;
+ dev->watchdog_timeo = 0;
+
+ dev->netdev_ops = &netdev_ops;
+ dev->destructor = free_netdev;
+}
+
+static struct device_type bt_type = {
+ .name = "bluetooth",
+};
+
+static void set_addr(u8 *eui, u8 *addr, u8 addr_type)
+{
+ /* addr is the BT address in little-endian format */
+ eui[0] = addr[5];
+ eui[1] = addr[4];
+ eui[2] = addr[3];
+ eui[3] = 0xFF;
+ eui[4] = 0xFE;
+ eui[5] = addr[2];
+ eui[6] = addr[1];
+ eui[7] = addr[0];
+
+ eui[0] ^= 2;
+
+ /*
+ * Universal/local bit set, RFC 4291
+ */
+ if (addr_type == BDADDR_LE_PUBLIC)
+ eui[0] |= 1;
+ else
+ eui[0] &= ~1;
+}
+
+static void set_dev_addr(struct net_device *net, bdaddr_t *addr,
+ u8 addr_type)
+{
+ net->addr_assign_type = NET_ADDR_PERM;
+ set_addr(net->dev_addr, addr->b, addr_type);
+ net->dev_addr[0] ^= 2;
+}
+
+static void ifup(struct net_device *net)
+{
+ int err;
+
+ rtnl_lock();
+ err = dev_open(net);
+ if (err < 0)
+ BT_INFO("iface %s cannot be opened (%d)", net->name, err);
+ rtnl_unlock();
+}
+
+/*
+ * This gets called when BT LE 6LoWPAN device is connected. We then
+ * create network device that acts as a proxy between BT LE device
+ * and kernel network stack.
+ */
+int bt_6lowpan_add_conn(struct l2cap_conn *conn)
+{
+ struct lowpan_info *dev = NULL;
+ struct peer *peer = NULL;
+ struct net_device *net;
+ struct lowpan_dev *entry;
+ int err = 0;
+
+ peer = lookup_peer(conn, &dev);
+ if (peer)
+ return -EEXIST;
+
+ /*
+ * If net device exists already, just add route.
+ */
+ if (dev && !peer)
+ goto add_peer;
+
+ net = alloc_netdev(sizeof(struct lowpan_info), IFACE_NAME_TEMPLATE,
+ netdev_setup);
+ if (!net)
+ return -ENOMEM;
+
+ dev = netdev_priv(net);
+ dev->net = net;
+ INIT_LIST_HEAD(&dev->peers);
+
+ set_dev_addr(net, &conn->hcon->src, conn->hcon->src_type);
+
+ net->netdev_ops = &netdev_ops;
+ SET_NETDEV_DEV(net, &conn->hcon->dev);
+ SET_NETDEV_DEVTYPE(net, &bt_type);
+
+ err = register_netdev(net);
+ if (err < 0) {
+ BT_INFO("register_netdev failed %d", err);
+ free_netdev(net);
+ goto out;
+ }
+
+ BT_DBG("ifindex %d peer bdaddr %pMR my addr %pMR",
+ net->ifindex, &conn->hcon->dst, &conn->hcon->src);
+ set_bit(__LINK_STATE_PRESENT, &net->state);
+
+ entry = kzalloc(sizeof(struct lowpan_dev), GFP_KERNEL);
+ if (!entry) {
+ unregister_netdev(net);
+ return -ENOMEM;
+ }
+
+ entry->dev = net;
+
+ write_lock(&devices_lock);
+ INIT_LIST_HEAD(&entry->list);
+ list_add(&entry->list, &bt_6lowpan_devices);
+ write_unlock(&devices_lock);
+
+ ifup(net);
+
+add_peer:
+ peer = kzalloc(sizeof(struct peer), GFP_KERNEL);
+ if (!peer)
+ return -ENOMEM;
+
+ peer->conn = conn;
+ memset(&peer->peer_addr, 0, sizeof(struct in6_addr));
+
+ /* RFC 2464 ch. 5 */
+ peer->peer_addr.s6_addr[0] = 0xFE;
+ peer->peer_addr.s6_addr[1] = 0x80;
+ set_addr((u8 *)&peer->peer_addr.s6_addr + 8, conn->hcon->dst.b,
+ conn->hcon->dst_type);
+
+ memcpy(&peer->eui64_addr, (u8 *)&peer->peer_addr.s6_addr + 8,
+ EUI64_ADDR_LEN);
+
+ write_lock(&devices_lock);
+ INIT_LIST_HEAD(&peer->list);
+ peer_add(dev, peer);
+ write_unlock(&devices_lock);
+
+ netdev_notify_peers(dev->net); /* send neighbour adv at startup */
+
+out:
+ return err;
+}
+
+static void delete_netdev(struct work_struct *work)
+{
+ struct lowpan_dev *entry = container_of(work, struct lowpan_dev,
+ delete_netdev);
+
+ unregister_netdev(entry->dev);
+
+ /* The entry pointer is deleted in device_event() */
+}
+
+int bt_6lowpan_del_conn(struct l2cap_conn *conn)
+{
+ struct lowpan_dev *entry, *tmp;
+ struct lowpan_info *info = NULL;
+ struct peer *peer;
+ int err = -ENOENT;
+
+ write_lock(&devices_lock);
+
+ list_for_each_entry_safe(entry, tmp, &bt_6lowpan_devices, list) {
+ info = lowpan_info(entry->dev);
+ peer = peer_lookup_conn(info, conn);
+ if (peer) {
+ peer_del(info, peer);
+ err = 0;
+ break;
+ }
+ }
+
+ write_unlock(&devices_lock);
+
+ if (!err && info && info->peer_count == 0) {
+ /*
+ * This function is called with hci dev lock held which means
+ * that we must delete the netdevice in worker thread.
+ */
+ INIT_WORK(&entry->delete_netdev, delete_netdev);
+ schedule_work(&entry->delete_netdev);
+ }
+
+ return err;
+}
+
+static int device_event(struct notifier_block *unused,
+ unsigned long event, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+ struct lowpan_dev *entry, *tmp;
+
+ if (dev->type != ARPHRD_RAWIP)
+ return NOTIFY_DONE;
+
+ switch (event) {
+ case NETDEV_UNREGISTER:
+ write_lock(&devices_lock);
+ list_for_each_entry_safe(entry, tmp, &bt_6lowpan_devices,
+ list) {
+ if (entry->dev == dev) {
+ list_del(&entry->list);
+ kfree(entry);
+ break;
+ }
+ }
+ write_unlock(&devices_lock);
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block bt_6lowpan_dev_notifier = {
+ .notifier_call = device_event,
+};
+
+int bt_6lowpan_init(void)
+{
+ return register_netdevice_notifier(&bt_6lowpan_dev_notifier);
+}
+
+void bt_6lowpan_cleanup(void)
+{
+ unregister_netdevice_notifier(&bt_6lowpan_dev_notifier);
+}
diff --git a/net/bluetooth/6lowpan.h b/net/bluetooth/6lowpan.h
new file mode 100644
index 0000000..680eac8
--- /dev/null
+++ b/net/bluetooth/6lowpan.h
@@ -0,0 +1,26 @@
+/*
+ Copyright (c) 2013 Intel Corp.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License version 2 and
+ only 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.
+*/
+
+#ifndef __6LOWPAN_H
+#define __6LOWPAN_H
+
+#include <linux/skbuff.h>
+#include <net/bluetooth/l2cap.h>
+
+int bt_6lowpan_recv(struct l2cap_conn *conn, struct sk_buff *skb);
+int bt_6lowpan_add_conn(struct l2cap_conn *conn);
+int bt_6lowpan_del_conn(struct l2cap_conn *conn);
+int bt_6lowpan_init(void);
+void bt_6lowpan_cleanup(void);
+
+#endif /* __6LOWPAN_H */
diff --git a/net/bluetooth/Makefile b/net/bluetooth/Makefile
index 6a791e7..80cb215 100644
--- a/net/bluetooth/Makefile
+++ b/net/bluetooth/Makefile
@@ -10,6 +10,6 @@ obj-$(CONFIG_BT_HIDP) += hidp/
bluetooth-y := af_bluetooth.o hci_core.o hci_conn.o hci_event.o mgmt.o \
hci_sock.o hci_sysfs.o l2cap_core.o l2cap_sock.o smp.o sco.o lib.o \
- a2mp.o amp.o
+ a2mp.o amp.o 6lowpan.o
subdir-ccflags-y += -D__CHECK_ENDIAN__
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 4af3821..155485f 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -40,6 +40,7 @@
#include "smp.h"
#include "a2mp.h"
#include "amp.h"
+#include "6lowpan.h"
bool disable_ertm;
@@ -6473,6 +6474,10 @@ static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
l2cap_conn_del(conn->hcon, EACCES);
break;
+ case L2CAP_FC_6LOWPAN:
+ bt_6lowpan_recv(conn, skb);
+ break;
+
default:
l2cap_data_channel(conn, cid, skb);
break;
@@ -6510,6 +6515,11 @@ int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr)
return exact ? lm1 : lm2;
}
+static bool is_bt_6lowpan(struct hci_conn *hcon)
+{
+ return false;
+}
+
void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
{
struct l2cap_conn *conn;
@@ -6518,8 +6528,12 @@ void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
if (!status) {
conn = l2cap_conn_add(hcon);
- if (conn)
+ if (conn) {
l2cap_conn_ready(conn);
+
+ if (is_bt_6lowpan(hcon))
+ bt_6lowpan_add_conn(conn);
+ }
} else {
l2cap_conn_del(hcon, bt_to_errno(status));
}
@@ -6540,6 +6554,9 @@ void l2cap_disconn_cfm(struct hci_conn *hcon, u8 reason)
{
BT_DBG("hcon %p reason %d", hcon, reason);
+ if (is_bt_6lowpan(hcon))
+ bt_6lowpan_del_conn(hcon->l2cap_data);
+
l2cap_conn_del(hcon, bt_to_errno(reason));
}
@@ -6817,11 +6834,14 @@ int __init l2cap_init(void)
l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
NULL, &l2cap_debugfs_fops);
+ bt_6lowpan_init();
+
return 0;
}
void l2cap_exit(void)
{
+ bt_6lowpan_cleanup();
debugfs_remove(l2cap_debugfs);
l2cap_cleanup_sockets();
}
--
1.8.3.1
^ permalink raw reply related [flat|nested] 9+ messages in thread* [RFC v4 4/6] Bluetooth: Enable 6LoWPAN support for BT LE devices
2013-11-13 10:11 [RFC v4 0/6] Bluetooth LE 6LoWPAN Jukka Rissanen
` (2 preceding siblings ...)
2013-11-13 10:11 ` [RFC v4 3/6] Bluetooth: Initial skeleton code for BT 6LoWPAN Jukka Rissanen
@ 2013-11-13 10:11 ` Jukka Rissanen
2013-11-13 10:11 ` [RFC v4 5/6] Bluetooth: Enable 6LoWPAN if device supports it Jukka Rissanen
2013-11-13 10:11 ` [RFC v4 6/6] Bluetooth: Manually enable or disable 6LoWPAN between devices Jukka Rissanen
5 siblings, 0 replies; 9+ messages in thread
From: Jukka Rissanen @ 2013-11-13 10:11 UTC (permalink / raw)
To: linux-bluetooth
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
---
net/bluetooth/6lowpan.c | 1042 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 1040 insertions(+), 2 deletions(-)
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 85754e2..5f0489c 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -11,6 +11,20 @@
GNU General Public License for more details.
*/
+/*
+ * The compression, uncompression and IPv6 packet code
+ * is from net/ieee802154/6lowpan.c with these copyrights
+ *
+ * Copyright 2011, Siemens AG
+ * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
+ *
+ * Based on patches from Jon Smirl <jonsmirl@gmail.com>
+ * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
+ *
+ * Jon's code is based on 6lowpan implementation for Contiki which is:
+ * Copyright (c) 2008, Swedish Institute of Computer Science.
+ */
+
#include <linux/version.h>
#include <linux/bitops.h>
#include <linux/if_arp.h>
@@ -172,8 +186,574 @@ static inline void raw_dump_table(const char *caller, char *msg,
16, 1, buf, len, false);
}
-static int recv_pkt(struct sk_buff *skb, struct net_device *dev)
+static inline bool fetch_skb(struct sk_buff *skb,
+ void *data, const unsigned int len)
+{
+ if (unlikely(!pskb_may_pull(skb, len)))
+ return true;
+
+ skb_copy_from_linear_data(skb, data, len);
+ skb_pull(skb, len);
+
+ return false;
+}
+
+/*
+ * Uncompress address function for source and
+ * destination address(non-multicast).
+ *
+ * address_mode is sam value or dam value.
+ */
+static int uncompress_addr(struct sk_buff *skb,
+ struct in6_addr *ipaddr,
+ const u8 address_mode,
+ const u8 *lladdr)
+{
+ bool fail;
+
+ switch (address_mode) {
+ case LOWPAN_IPHC_ADDR_00:
+ /* for global link addresses */
+ fail = fetch_skb(skb, ipaddr->s6_addr, 16);
+ break;
+ case LOWPAN_IPHC_ADDR_01:
+ /* fe:80::XXXX:XXXX:XXXX:XXXX */
+ ipaddr->s6_addr[0] = 0xFE;
+ ipaddr->s6_addr[1] = 0x80;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[8], 8);
+ break;
+ case LOWPAN_IPHC_ADDR_02:
+ /* fe:80::ff:fe00:XXXX */
+ ipaddr->s6_addr[0] = 0xFE;
+ ipaddr->s6_addr[1] = 0x80;
+ ipaddr->s6_addr[11] = 0xFF;
+ ipaddr->s6_addr[12] = 0xFE;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[14], 2);
+ break;
+ case LOWPAN_IPHC_ADDR_03:
+ fail = false;
+ /* XXX: support only normal addr (IEEE802154_ADDR_LONG) atm */
+
+ /* fe:80::XXXX:XXXX:XXXX:XXXX
+ * \_________________/
+ * hwaddr
+ */
+ ipaddr->s6_addr[0] = 0xFE;
+ ipaddr->s6_addr[1] = 0x80;
+ memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN);
+ break;
+ default:
+ pr_debug("Invalid address mode value: 0x%x\n", address_mode);
+ return -EINVAL;
+ }
+
+ if (fail) {
+ pr_debug("Failed to fetch skb data\n");
+ return -EIO;
+ }
+
+ raw_dump_inline(NULL, "Reconstructed ipv6 addr is",
+ ipaddr->s6_addr, 16);
+
+ return 0;
+}
+
+/*
+ * Uncompress address function for source context
+ * based address(non-multicast).
+ */
+static int uncompress_context_based_src_addr(struct sk_buff *skb,
+ struct in6_addr *ipaddr,
+ const u8 sam)
+{
+ switch (sam) {
+ case LOWPAN_IPHC_ADDR_00:
+ /* unspec address ::
+ * Do nothing, address is already ::
+ */
+ break;
+ case LOWPAN_IPHC_ADDR_01:
+ /* TODO */
+ case LOWPAN_IPHC_ADDR_02:
+ /* TODO */
+ case LOWPAN_IPHC_ADDR_03:
+ /* TODO */
+ netdev_warn(skb->dev, "SAM value 0x%x not supported\n", sam);
+ return -EINVAL;
+ default:
+ pr_debug("Invalid sam value: 0x%x\n", sam);
+ return -EINVAL;
+ }
+
+ raw_dump_inline(NULL,
+ "Reconstructed context based ipv6 src addr is",
+ ipaddr->s6_addr, 16);
+
+ return 0;
+}
+
+/*
+ * This func is called when the packet from BT LE device
+ * needs to be sent upper layers.
+ */
+static int give_skb_to_upper(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct sk_buff *skb_cp;
+ int ret = NET_RX_SUCCESS;
+
+ skb_cp = skb_copy(skb, GFP_ATOMIC);
+ if (!skb_cp) {
+ ret = -ENOMEM;
+ } else {
+ ret = netif_rx(skb_cp);
+
+ BT_DBG("receive skb %d", ret);
+ if (ret < 0)
+ ret = NET_RX_DROP;
+ }
+
+ return ret;
+}
+
+static inline int 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 fetch_skb_u16(struct sk_buff *skb, u16 *val)
{
+ if (unlikely(!pskb_may_pull(skb, 2)))
+ return -EINVAL;
+
+ *val = (skb->data[0] << 8) | skb->data[1];
+ skb_pull(skb, 2);
+
+ return 0;
+}
+
+static int skb_deliver(struct sk_buff *skb, struct ipv6hdr *hdr,
+ struct net_device *dev)
+{
+ struct sk_buff *new;
+ int stat;
+
+ new = skb_copy_expand(skb, sizeof(struct ipv6hdr), skb_tailroom(skb),
+ GFP_ATOMIC);
+ kfree_skb(skb);
+
+ if (!new)
+ return -ENOMEM;
+
+ skb_push(new, sizeof(struct ipv6hdr));
+ skb_reset_network_header(new);
+ skb_copy_to_linear_data(new, hdr, sizeof(struct ipv6hdr));
+
+ new->protocol = htons(ETH_P_IPV6);
+ new->pkt_type = PACKET_HOST;
+ new->dev = dev;
+
+ raw_dump_table(__func__,
+ "raw skb data dump before receiving",
+ new->data, new->len);
+
+ stat = give_skb_to_upper(new, dev);
+
+ kfree_skb(new);
+
+ return stat;
+}
+
+/* Uncompress function for multicast destination address,
+ * when M bit is set.
+ */
+static int
+lowpan_uncompress_multicast_daddr(struct sk_buff *skb,
+ struct in6_addr *ipaddr,
+ const u8 dam)
+{
+ bool fail;
+
+ switch (dam) {
+ case LOWPAN_IPHC_DAM_00:
+ /* 00: 128 bits. The full address
+ * is carried in-line.
+ */
+ fail = fetch_skb(skb, ipaddr->s6_addr, 16);
+ break;
+ case LOWPAN_IPHC_DAM_01:
+ /* 01: 48 bits. The address takes
+ * the form ffXX::00XX:XXXX:XXXX.
+ */
+ ipaddr->s6_addr[0] = 0xFF;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[1], 1);
+ fail |= fetch_skb(skb, &ipaddr->s6_addr[11], 5);
+ break;
+ case LOWPAN_IPHC_DAM_10:
+ /* 10: 32 bits. The address takes
+ * the form ffXX::00XX:XXXX.
+ */
+ ipaddr->s6_addr[0] = 0xFF;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[1], 1);
+ fail |= fetch_skb(skb, &ipaddr->s6_addr[13], 3);
+ break;
+ case LOWPAN_IPHC_DAM_11:
+ /* 11: 8 bits. The address takes
+ * the form ff02::00XX.
+ */
+ ipaddr->s6_addr[0] = 0xFF;
+ ipaddr->s6_addr[1] = 0x02;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[15], 1);
+ break;
+ default:
+ pr_debug("DAM value has a wrong value: 0x%x\n", dam);
+ return -EINVAL;
+ }
+
+ if (fail) {
+ pr_debug("Failed to fetch skb data\n");
+ return -EIO;
+ }
+
+ raw_dump_inline(NULL, "Reconstructed ipv6 multicast addr is",
+ ipaddr->s6_addr, 16);
+
+ return 0;
+}
+
+static int
+uncompress_udp_header(struct sk_buff *skb, struct udphdr *uh)
+{
+ u8 tmp;
+
+ if (!uh)
+ goto err;
+
+ if (fetch_skb_u8(skb, &tmp))
+ goto err;
+
+ if ((tmp & LOWPAN_NHC_UDP_MASK) == LOWPAN_NHC_UDP_ID) {
+ pr_debug("UDP header uncompression\n");
+ switch (tmp & LOWPAN_NHC_UDP_CS_P_11) {
+ case LOWPAN_NHC_UDP_CS_P_00:
+ memcpy(&uh->source, &skb->data[0], 2);
+ memcpy(&uh->dest, &skb->data[2], 2);
+ skb_pull(skb, 4);
+ break;
+ case LOWPAN_NHC_UDP_CS_P_01:
+ memcpy(&uh->source, &skb->data[0], 2);
+ uh->dest =
+ skb->data[2] + LOWPAN_NHC_UDP_8BIT_PORT;
+ skb_pull(skb, 3);
+ break;
+ case LOWPAN_NHC_UDP_CS_P_10:
+ uh->source = skb->data[0] + LOWPAN_NHC_UDP_8BIT_PORT;
+ memcpy(&uh->dest, &skb->data[1], 2);
+ skb_pull(skb, 3);
+ break;
+ case LOWPAN_NHC_UDP_CS_P_11:
+ uh->source =
+ LOWPAN_NHC_UDP_4BIT_PORT + (skb->data[0] >> 4);
+ uh->dest =
+ LOWPAN_NHC_UDP_4BIT_PORT + (skb->data[0] & 0x0f);
+ skb_pull(skb, 1);
+ break;
+ default:
+ pr_debug("ERROR: unknown UDP format\n");
+ goto err;
+ break;
+ }
+
+ pr_debug("uncompressed UDP ports: src = %d, dst = %d\n",
+ uh->source, uh->dest);
+
+ /* copy checksum */
+ memcpy(&uh->check, &skb->data[0], 2);
+ skb_pull(skb, 2);
+
+ /*
+ * UDP lenght needs to be infered from the lower layers
+ * here, we obtain the hint from the remaining size of the
+ * frame
+ */
+ uh->len = htons(skb->len + sizeof(struct udphdr));
+ pr_debug("uncompressed UDP length: src = %d", uh->len);
+ } else {
+ pr_debug("ERROR: unsupported NH format\n");
+ goto err;
+ }
+
+ return 0;
+err:
+ return -EINVAL;
+}
+
+/* TTL uncompression values */
+static const u8 lowpan_ttl_values[] = { 0, 1, 64, 255 };
+
+static int process_data(struct sk_buff *skb, struct net_device *dev,
+ struct l2cap_conn *conn)
+{
+ struct ipv6hdr hdr = {};
+ u8 tmp, iphc0, iphc1, num_context = 0;
+ const u8 *_saddr = NULL, *_daddr = NULL;
+ struct lowpan_info *info;
+ struct peer *peer;
+ int err;
+
+ raw_dump_table(__func__, "raw skb data dump uncompressed",
+ skb->data, skb->len);
+
+ /* at least two bytes will be used for the encoding */
+ if (skb->len < 2)
+ goto drop;
+
+ if (fetch_skb_u8(skb, &iphc0))
+ goto drop;
+
+ info = lowpan_info(dev);
+
+ if (fetch_skb_u8(skb, &iphc1))
+ goto drop;
+
+ write_lock(&devices_lock);
+ peer = peer_lookup_conn(info, conn);
+ write_unlock(&devices_lock);
+ if (!peer)
+ goto drop;
+
+ _saddr = peer->eui64_addr;
+ _daddr = info->net->dev_addr;
+
+ /* another if the CID flag is set */
+ if (iphc1 & LOWPAN_IPHC_CID) {
+ pr_debug("CID flag is set, increase header with one\n");
+ if (fetch_skb_u8(skb, &num_context))
+ goto drop;
+ }
+
+ hdr.version = 6;
+
+ /* Traffic Class and Flow Label */
+ switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) {
+ /*
+ * Traffic Class and FLow Label carried in-line
+ * ECN + DSCP + 4-bit Pad + Flow Label (4 bytes)
+ */
+ case 0: /* 00b */
+ if (fetch_skb_u8(skb, &tmp))
+ goto drop;
+
+ memcpy(&hdr.flow_lbl, &skb->data[0], 3);
+ skb_pull(skb, 3);
+ hdr.priority = ((tmp >> 2) & 0x0f);
+ hdr.flow_lbl[0] = ((tmp >> 2) & 0x30) | (tmp << 6) |
+ (hdr.flow_lbl[0] & 0x0f);
+ break;
+ /*
+ * Traffic class carried in-line
+ * ECN + DSCP (1 byte), Flow Label is elided
+ */
+ case 2: /* 10b */
+ if (fetch_skb_u8(skb, &tmp))
+ goto drop;
+
+ hdr.priority = ((tmp >> 2) & 0x0f);
+ hdr.flow_lbl[0] = ((tmp << 6) & 0xC0) | ((tmp >> 2) & 0x30);
+ break;
+ /*
+ * Flow Label carried in-line
+ * ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided
+ */
+ case 1: /* 01b */
+ if (fetch_skb_u8(skb, &tmp))
+ goto drop;
+
+ hdr.flow_lbl[0] = (skb->data[0] & 0x0F) | ((tmp >> 2) & 0x30);
+ memcpy(&hdr.flow_lbl[1], &skb->data[0], 2);
+ skb_pull(skb, 2);
+ break;
+ /* Traffic Class and Flow Label are elided */
+ case 3: /* 11b */
+ break;
+ default:
+ break;
+ }
+
+ /* Next Header */
+ if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) {
+ /* Next header is carried inline */
+ if (fetch_skb_u8(skb, &(hdr.nexthdr)))
+ goto drop;
+
+ pr_debug("NH flag is set, next header carried inline: %02x\n",
+ hdr.nexthdr);
+ }
+
+ /* Hop Limit */
+ if ((iphc0 & 0x03) != LOWPAN_IPHC_TTL_I)
+ hdr.hop_limit = lowpan_ttl_values[iphc0 & 0x03];
+ else {
+ if (fetch_skb_u8(skb, &(hdr.hop_limit)))
+ goto drop;
+ }
+
+ /* Extract SAM to the tmp variable */
+ tmp = ((iphc1 & LOWPAN_IPHC_SAM) >> LOWPAN_IPHC_SAM_BIT) & 0x03;
+
+ if (iphc1 & LOWPAN_IPHC_SAC) {
+ /* Source address context based uncompression */
+ pr_debug("SAC bit is set. Handle context based source address.\n");
+ err = uncompress_context_based_src_addr(
+ skb, &hdr.saddr, tmp);
+ } else {
+ /* Source address uncompression */
+ pr_debug("source address stateless compression\n");
+ err = uncompress_addr(skb, &hdr.saddr, tmp, _saddr);
+ }
+
+ /* Check on error of previous branch */
+ if (err)
+ goto drop;
+
+ /* Extract DAM to the tmp variable */
+ tmp = ((iphc1 & LOWPAN_IPHC_DAM_11) >> LOWPAN_IPHC_DAM_BIT) & 0x03;
+
+ /* check for Multicast Compression */
+ if (iphc1 & LOWPAN_IPHC_M) {
+ if (iphc1 & LOWPAN_IPHC_DAC) {
+ pr_debug("dest: context-based mcast compression\n");
+ /* TODO: implement this */
+ } else {
+ err = lowpan_uncompress_multicast_daddr(
+ skb, &hdr.daddr, tmp);
+ if (err)
+ goto drop;
+ }
+ } else {
+ err = uncompress_addr(skb, &hdr.daddr, tmp, _daddr);
+ pr_debug("dest: stateless compression mode %d dest %pI6c\n",
+ tmp, &hdr.daddr);
+ if (err)
+ goto drop;
+ }
+
+ /* UDP data uncompression */
+ if (iphc0 & LOWPAN_IPHC_NH_C) {
+ struct udphdr uh;
+ struct sk_buff *new;
+ if (uncompress_udp_header(skb, &uh))
+ goto drop;
+
+ /*
+ * replace the compressed UDP head by the uncompressed UDP
+ * header
+ */
+ new = skb_copy_expand(skb, sizeof(struct udphdr),
+ skb_tailroom(skb), GFP_ATOMIC);
+ kfree_skb(skb);
+
+ if (!new)
+ return -ENOMEM;
+
+ skb = new;
+
+ skb_push(skb, sizeof(struct udphdr));
+ skb_reset_transport_header(skb);
+ skb_copy_to_linear_data(skb, &uh, sizeof(struct udphdr));
+
+ raw_dump_table(__func__, "raw UDP header dump",
+ (u8 *)&uh, sizeof(uh));
+
+ hdr.nexthdr = UIP_PROTO_UDP;
+ }
+
+ hdr.payload_len = htons(skb->len);
+
+ pr_debug("skb headroom size = %d, data length = %d\n",
+ skb_headroom(skb), skb->len);
+
+ pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n\t"
+ "nexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
+ hdr.version, ntohs(hdr.payload_len), hdr.nexthdr,
+ hdr.hop_limit, &hdr.daddr);
+
+ raw_dump_table(__func__, "raw header dump", (u8 *)&hdr,
+ sizeof(hdr));
+
+ return skb_deliver(skb, &hdr, dev);
+
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
+ struct l2cap_conn *conn)
+{
+ struct sk_buff *local_skb;
+
+ if (!netif_running(dev))
+ goto drop;
+
+ if (dev->type != ARPHRD_RAWIP)
+ goto drop;
+
+ /* check that it's our buffer */
+ if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
+ /* Copy the packet so that the IPv6 header is
+ * properly aligned.
+ */
+ local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
+ skb_tailroom(skb), GFP_ATOMIC);
+ if (!local_skb)
+ goto drop;
+
+ local_skb->protocol = htons(ETH_P_IPV6);
+ local_skb->pkt_type = PACKET_HOST;
+
+ skb_reset_network_header(local_skb);
+ skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
+
+ if (give_skb_to_upper(local_skb, dev) != NET_RX_SUCCESS) {
+ kfree_skb(local_skb);
+ goto drop;
+ }
+
+ dev->stats.rx_bytes += skb->len;
+ dev->stats.rx_packets++;
+
+ kfree_skb(local_skb);
+ kfree_skb(skb);
+ } else {
+ switch (skb->data[0] & 0xe0) {
+ case LOWPAN_DISPATCH_IPHC: /* ipv6 datagram */
+ local_skb = skb_clone(skb, GFP_ATOMIC);
+ if (!local_skb)
+ goto drop;
+ if (process_data(local_skb, dev, conn)
+ != NET_RX_SUCCESS)
+ goto drop;
+
+ dev->stats.rx_bytes += skb->len;
+ dev->stats.rx_packets++;
+
+ kfree_skb(skb);
+ break;
+ default:
+ break;
+ }
+ }
+
+ return NET_RX_SUCCESS;
+
+drop:
kfree_skb(skb);
return NET_RX_DROP;
}
@@ -202,19 +782,472 @@ static void do_send(struct l2cap_conn *conn, struct sk_buff *skb)
BT_DBG("conn %p, skb %p len %d priority %u", conn, skb, skb->len,
skb->priority);
+ hci_send_acl(conn->hchan, skb, ACL_START);
return;
}
+static inline int skbuff_copy(void *msg, int len,
+ int count, int mtu,
+ struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct sk_buff **frag;
+ int sent = 0;
+
+ memcpy(skb_put(skb, count), msg, count);
+
+ sent += count;
+ msg += count;
+ len -= count;
+
+ dev->stats.tx_bytes += count;
+ dev->stats.tx_packets++;
+
+ raw_dump_table(__func__, "Sending", skb->data, skb->len);
+
+ /* Continuation fragments (no L2CAP header) */
+ frag = &skb_shinfo(skb)->frag_list;
+ while (len > 0) {
+ struct sk_buff *tmp;
+
+ count = min_t(unsigned int, mtu, len);
+
+ tmp = bt_skb_alloc(count, GFP_KERNEL);
+ if (IS_ERR(tmp))
+ return PTR_ERR(tmp);
+
+ *frag = tmp;
+
+ memcpy(skb_put(*frag, count), msg, count);
+
+ raw_dump_table(__func__, "Sending fragment",
+ (*frag)->data, count);
+
+ (*frag)->priority = skb->priority;
+
+ sent += count;
+ msg += count;
+ len -= count;
+
+ skb->len += (*frag)->len;
+ skb->data_len += (*frag)->len;
+
+ frag = &(*frag)->next;
+
+ dev->stats.tx_bytes += count;
+ dev->stats.tx_packets++;
+ }
+
+ return sent;
+}
+
+static struct sk_buff *create_pdu(struct l2cap_conn *conn,
+ void *msg, size_t len,
+ u32 priority,
+ struct net_device *dev)
+{
+ struct sk_buff *skb;
+ int err, count;
+ struct l2cap_hdr *lh;
+
+ if (conn->mtu > (L2CAP_LE_MIN_MTU + L2CAP_HDR_SIZE))
+ /* XXX: This should be not needed and atm is only used for
+ * testing purposes */
+ conn->mtu = L2CAP_LE_MIN_MTU + L2CAP_HDR_SIZE;
+
+ count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
+
+ BT_DBG("conn %p len %zu mtu %d count %d", conn, len, conn->mtu, count);
+
+ skb = bt_skb_alloc(count + L2CAP_HDR_SIZE, GFP_KERNEL);
+ if (IS_ERR(skb))
+ return skb;
+
+ skb->priority = priority;
+
+ lh = (struct l2cap_hdr *)skb_put(skb, L2CAP_HDR_SIZE);
+ lh->cid = cpu_to_le16(L2CAP_FC_6LOWPAN);
+ lh->len = cpu_to_le16(len);
+
+ err = skbuff_copy(msg, len, count, conn->mtu, skb, dev);
+ if (unlikely(err < 0)) {
+ kfree_skb(skb);
+ BT_DBG("skbuff copy %d failed", err);
+ return ERR_PTR(err);
+ }
+
+ return skb;
+}
+
static int conn_send(struct l2cap_conn *conn,
void *msg, size_t len, u32 priority,
struct net_device *dev)
{
- struct sk_buff *skb = {0};
+ struct sk_buff *skb;
+
+ skb = create_pdu(conn, msg, len, priority, dev);
+ if (IS_ERR(skb))
+ return -EINVAL;
do_send(conn, skb);
return 0;
}
+static u8 lowpan_compress_addr_64(u8 **hc06_ptr, u8 shift,
+ const struct in6_addr *ipaddr,
+ const unsigned char *lladdr)
+{
+ u8 val = 0;
+
+ if (is_addr_mac_addr_based(ipaddr, lladdr)) {
+ val = 3; /* 0-bits */
+ pr_debug("address compression 0 bits\n");
+ } else if (lowpan_is_iid_16_bit_compressable(ipaddr)) {
+ /* compress IID to 16 bits xxxx::XXXX */
+ memcpy(*hc06_ptr, &ipaddr->s6_addr16[7], 2);
+ *hc06_ptr += 2;
+ val = 2; /* 16-bits */
+ raw_dump_inline(NULL, "Compressed ipv6 addr is (16 bits)",
+ *hc06_ptr - 2, 2);
+ } else {
+ /* do not compress IID => xxxx::IID */
+ memcpy(*hc06_ptr, &ipaddr->s6_addr16[4], 8);
+ *hc06_ptr += 8;
+ val = 1; /* 64-bits */
+ raw_dump_inline(NULL, "Compressed ipv6 addr is (64 bits)",
+ *hc06_ptr - 8, 8);
+ }
+
+ return rol8(val, shift);
+}
+
+static void compress_udp_header(u8 **hc06_ptr, struct sk_buff *skb)
+{
+ struct udphdr *uh = udp_hdr(skb);
+
+ if (((uh->source & LOWPAN_NHC_UDP_4BIT_MASK) ==
+ LOWPAN_NHC_UDP_4BIT_PORT) &&
+ ((uh->dest & LOWPAN_NHC_UDP_4BIT_MASK) ==
+ LOWPAN_NHC_UDP_4BIT_PORT)) {
+ pr_debug("UDP header: both ports compression to 4 bits\n");
+ **hc06_ptr = LOWPAN_NHC_UDP_CS_P_11;
+ **(hc06_ptr + 1) = /* subtraction is faster */
+ (u8)((uh->dest - LOWPAN_NHC_UDP_4BIT_PORT) +
+ ((uh->source & LOWPAN_NHC_UDP_4BIT_PORT) << 4));
+ *hc06_ptr += 2;
+ } else if ((uh->dest & LOWPAN_NHC_UDP_8BIT_MASK) ==
+ LOWPAN_NHC_UDP_8BIT_PORT) {
+ pr_debug("UDP header: remove 8 bits of dest\n");
+ **hc06_ptr = LOWPAN_NHC_UDP_CS_P_01;
+ memcpy(*hc06_ptr + 1, &uh->source, 2);
+ **(hc06_ptr + 3) = (u8)(uh->dest - LOWPAN_NHC_UDP_8BIT_PORT);
+ *hc06_ptr += 4;
+ } else if ((uh->source & LOWPAN_NHC_UDP_8BIT_MASK) ==
+ LOWPAN_NHC_UDP_8BIT_PORT) {
+ pr_debug("UDP header: remove 8 bits of source\n");
+ **hc06_ptr = LOWPAN_NHC_UDP_CS_P_10;
+ memcpy(*hc06_ptr + 1, &uh->dest, 2);
+ **(hc06_ptr + 3) = (u8)(uh->source - LOWPAN_NHC_UDP_8BIT_PORT);
+ *hc06_ptr += 4;
+ } else {
+ pr_debug("UDP header: can't compress\n");
+ **hc06_ptr = LOWPAN_NHC_UDP_CS_P_00;
+ memcpy(*hc06_ptr + 1, &uh->source, 2);
+ memcpy(*hc06_ptr + 3, &uh->dest, 2);
+ *hc06_ptr += 5;
+ }
+
+ /* checksum is always inline */
+ memcpy(*hc06_ptr, &uh->check, 2);
+ *hc06_ptr += 2;
+
+ /* skip the UDP header */
+ skb_pull(skb, sizeof(struct udphdr));
+}
+
+static inline int lowpan_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 lowpan_fetch_skb_u16(struct sk_buff *skb, u16 *val)
+{
+ if (unlikely(!pskb_may_pull(skb, 2)))
+ return -EINVAL;
+
+ *val = (skb->data[0] << 8) | skb->data[1];
+ skb_pull(skb, 2);
+
+ return 0;
+}
+
+static void get_dest_bdaddr(struct in6_addr *ip6_daddr,
+ bdaddr_t *addr, u8 *addr_type)
+{
+ u8 *eui64;
+
+ eui64 = ip6_daddr->s6_addr + 8;
+
+ addr->b[0] = eui64[7];
+ addr->b[1] = eui64[6];
+ addr->b[2] = eui64[5];
+ addr->b[3] = eui64[2];
+ addr->b[4] = eui64[1];
+ addr->b[5] = eui64[0];
+
+ addr->b[5] ^= 2;
+
+ /* Set universal/local bit to 0 */
+ if (addr->b[5] & 1) {
+ addr->b[5] &= ~1;
+ *addr_type = BDADDR_LE_PUBLIC;
+ } else
+ *addr_type = BDADDR_LE_RANDOM;
+}
+
+static int header_create(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type, const void *_daddr,
+ const void *_saddr, unsigned int len)
+{
+ u8 tmp, iphc0, iphc1, *hc06_ptr;
+ struct lowpan_info *info;
+ struct peer *peer;
+ struct ipv6hdr *hdr;
+ bdaddr_t addr, *any = BDADDR_ANY;
+ u8 *saddr, *daddr = any->b;
+ u8 addr_type;
+ u8 head[100] = {0};
+
+ if (type != ETH_P_IPV6)
+ return -EINVAL;
+
+ hdr = ipv6_hdr(skb);
+ hc06_ptr = head + 2;
+
+ pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n"
+ "\tnexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
+ hdr->version, ntohs(hdr->payload_len), hdr->nexthdr,
+ hdr->hop_limit, &hdr->daddr);
+
+ raw_dump_table(__func__, "raw skb network header dump",
+ skb_network_header(skb), sizeof(struct ipv6hdr));
+
+ info = lowpan_info(dev);
+
+ if (ipv6_addr_is_multicast(&hdr->daddr)) {
+ memcpy(&lowpan_cb(skb)->addr, &hdr->daddr,
+ sizeof(struct in6_addr));
+ lowpan_cb(skb)->conn = NULL;
+ } else {
+ /*
+ * Get destination BT device from skb.
+ * If there is no such peer then discard the packet.
+ */
+ get_dest_bdaddr(&hdr->daddr, &addr, &addr_type);
+
+ BT_DBG("dest addr %pMR type %d", &addr, addr_type);
+
+ write_lock(&devices_lock);
+ peer = peer_lookup_ba(info, addr_type, &addr);
+ write_unlock(&devices_lock);
+
+ if (!peer) {
+ BT_DBG("no such peer %pMR found", &addr);
+ return -ENOENT;
+ }
+
+ daddr = peer->eui64_addr;
+
+ memcpy(&lowpan_cb(skb)->addr, &hdr->daddr,
+ sizeof(struct in6_addr));
+ lowpan_cb(skb)->conn = peer->conn;
+ }
+
+ saddr = info->net->dev_addr;
+
+ raw_dump_inline(__func__, "saddr",
+ (unsigned char *)saddr, 8);
+
+ /*
+ * As we copy some bit-length fields, in the IPHC encoding bytes,
+ * we sometimes use |=
+ * If the field is 0, and the current bit value in memory is 1,
+ * this does not work. We therefore reset the IPHC encoding here
+ */
+ iphc0 = LOWPAN_DISPATCH_IPHC;
+ iphc1 = 0;
+
+ /* TODO: context lookup */
+
+ raw_dump_inline(__func__, "daddr",
+ (unsigned char *)daddr, 8);
+
+ raw_dump_table(__func__,
+ "sending raw skb network uncompressed packet",
+ skb->data, skb->len);
+
+ /*
+ * Traffic class, flow label
+ * If flow label is 0, compress it. If traffic class is 0, compress it
+ * We have to process both in the same time as the offset of traffic
+ * class depends on the presence of version and flow label
+ */
+
+ /* hc06 format of TC is ECN | DSCP , original one is DSCP | ECN */
+ tmp = (hdr->priority << 4) | (hdr->flow_lbl[0] >> 4);
+ tmp = ((tmp & 0x03) << 6) | (tmp >> 2);
+
+ if (((hdr->flow_lbl[0] & 0x0F) == 0) &&
+ (hdr->flow_lbl[1] == 0) && (hdr->flow_lbl[2] == 0)) {
+ /* flow label can be compressed */
+ iphc0 |= LOWPAN_IPHC_FL_C;
+ if ((hdr->priority == 0) &&
+ ((hdr->flow_lbl[0] & 0xF0) == 0)) {
+ /* compress (elide) all */
+ iphc0 |= LOWPAN_IPHC_TC_C;
+ } else {
+ /* compress only the flow label */
+ *hc06_ptr = tmp;
+ hc06_ptr += 1;
+ }
+ } else {
+ /* Flow label cannot be compressed */
+ if ((hdr->priority == 0) &&
+ ((hdr->flow_lbl[0] & 0xF0) == 0)) {
+ /* compress only traffic class */
+ iphc0 |= LOWPAN_IPHC_TC_C;
+ *hc06_ptr = (tmp & 0xc0) | (hdr->flow_lbl[0] & 0x0F);
+ memcpy(hc06_ptr + 1, &hdr->flow_lbl[1], 2);
+ hc06_ptr += 3;
+ } else {
+ /* compress nothing */
+ memcpy(hc06_ptr, &hdr, 4);
+ /* replace the top byte with new ECN | DSCP format */
+ *hc06_ptr = tmp;
+ hc06_ptr += 4;
+ }
+ }
+
+ /* NOTE: payload length is always compressed */
+
+ /* Next Header is compress if UDP */
+ if (hdr->nexthdr == UIP_PROTO_UDP)
+ iphc0 |= LOWPAN_IPHC_NH_C;
+
+ if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) {
+ *hc06_ptr = hdr->nexthdr;
+ hc06_ptr += 1;
+ }
+
+ /*
+ * Hop limit
+ * if 1: compress, encoding is 01
+ * if 64: compress, encoding is 10
+ * if 255: compress, encoding is 11
+ * else do not compress
+ */
+ switch (hdr->hop_limit) {
+ case 1:
+ iphc0 |= LOWPAN_IPHC_TTL_1;
+ break;
+ case 64:
+ iphc0 |= LOWPAN_IPHC_TTL_64;
+ break;
+ case 255:
+ iphc0 |= LOWPAN_IPHC_TTL_255;
+ break;
+ default:
+ *hc06_ptr = hdr->hop_limit;
+ hc06_ptr += 1;
+ break;
+ }
+
+ /* source address compression */
+ if (is_addr_unspecified(&hdr->saddr)) {
+ pr_debug("source address is unspecified, setting SAC\n");
+ iphc1 |= LOWPAN_IPHC_SAC;
+ /* TODO: context lookup */
+ } else if (is_addr_link_local(&hdr->saddr)) {
+ iphc1 |= lowpan_compress_addr_64(&hc06_ptr,
+ LOWPAN_IPHC_SAM_BIT, &hdr->saddr, saddr);
+ pr_debug("source address unicast link-local %pI6c "
+ "iphc1 0x%02x\n", &hdr->saddr, iphc1);
+ } else {
+ pr_debug("send the full source address\n");
+ memcpy(hc06_ptr, &hdr->saddr.s6_addr16[0], 16);
+ hc06_ptr += 16;
+ }
+
+ /* destination address compression */
+ if (is_addr_mcast(&hdr->daddr)) {
+ pr_debug("destination address is multicast: ");
+ iphc1 |= LOWPAN_IPHC_M;
+ if (lowpan_is_mcast_addr_compressable8(&hdr->daddr)) {
+ pr_debug("compressed to 1 octet\n");
+ iphc1 |= LOWPAN_IPHC_DAM_11;
+ /* use last byte */
+ *hc06_ptr = hdr->daddr.s6_addr[15];
+ hc06_ptr += 1;
+ } else if (lowpan_is_mcast_addr_compressable32(&hdr->daddr)) {
+ pr_debug("compressed to 4 octets\n");
+ iphc1 |= LOWPAN_IPHC_DAM_10;
+ /* second byte + the last three */
+ *hc06_ptr = hdr->daddr.s6_addr[1];
+ memcpy(hc06_ptr + 1, &hdr->daddr.s6_addr[13], 3);
+ hc06_ptr += 4;
+ } else if (lowpan_is_mcast_addr_compressable48(&hdr->daddr)) {
+ pr_debug("compressed to 6 octets\n");
+ iphc1 |= LOWPAN_IPHC_DAM_01;
+ /* second byte + the last five */
+ *hc06_ptr = hdr->daddr.s6_addr[1];
+ memcpy(hc06_ptr + 1, &hdr->daddr.s6_addr[11], 5);
+ hc06_ptr += 6;
+ } else {
+ pr_debug("using full address\n");
+ iphc1 |= LOWPAN_IPHC_DAM_00;
+ memcpy(hc06_ptr, &hdr->daddr.s6_addr[0], 16);
+ hc06_ptr += 16;
+ }
+ } else {
+ /* TODO: context lookup */
+ if (is_addr_link_local(&hdr->daddr)) {
+ iphc1 |= lowpan_compress_addr_64(&hc06_ptr,
+ LOWPAN_IPHC_DAM_BIT, &hdr->daddr, daddr);
+ pr_debug("dest address unicast link-local %pI6c "
+ "iphc1 0x%02x\n", &hdr->daddr, iphc1);
+ } else {
+ pr_debug("dest address unicast %pI6c\n", &hdr->daddr);
+ memcpy(hc06_ptr, &hdr->daddr.s6_addr16[0], 16);
+ hc06_ptr += 16;
+ }
+ }
+
+ /* UDP header compression */
+ if (hdr->nexthdr == UIP_PROTO_UDP)
+ compress_udp_header(&hc06_ptr, skb);
+
+ head[0] = iphc0;
+ head[1] = iphc1;
+
+ skb_pull(skb, sizeof(struct ipv6hdr));
+
+ memcpy(skb_push(skb, hc06_ptr - head), head, hc06_ptr - head);
+
+ BT_DBG("header len %d skb %u", (int)(hc06_ptr - head), skb->len);
+
+ skb_reset_network_header(skb);
+
+ raw_dump_table(__func__, "raw skb data dump compressed",
+ skb->data, skb->len);
+ return 0;
+}
+
/* Packet to BT LE device */
static int send_pkt(struct l2cap_conn *conn, const void *saddr,
const void *daddr, struct sk_buff *skb,
@@ -305,6 +1338,10 @@ static const struct net_device_ops netdev_ops = {
.ndo_start_xmit = xmit,
};
+static struct header_ops header_ops = {
+ .create = header_create,
+};
+
static void netdev_setup(struct net_device *dev)
{
dev->addr_len = EUI64_ADDR_LEN;
@@ -318,6 +1355,7 @@ static void netdev_setup(struct net_device *dev)
dev->watchdog_timeo = 0;
dev->netdev_ops = &netdev_ops;
+ dev->header_ops = &header_ops;
dev->destructor = free_netdev;
}
--
1.8.3.1
^ permalink raw reply related [flat|nested] 9+ messages in thread