[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/net/netlink/Makefile b/ap/os/linux/linux-3.4.x/net/netlink/Makefile
new file mode 100644
index 0000000..bdd6ddf
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/net/netlink/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for the netlink driver.
+#
+
+obj-y  				:= af_netlink.o genetlink.o
diff --git a/ap/os/linux/linux-3.4.x/net/netlink/af_netlink.c b/ap/os/linux/linux-3.4.x/net/netlink/af_netlink.c
new file mode 100644
index 0000000..92ebaf6
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/net/netlink/af_netlink.c
@@ -0,0 +1,2242 @@
+/*
+ * NETLINK      Kernel-user communication protocol.
+ *
+ * 		Authors:	Alan Cox <alan@lxorguk.ukuu.org.uk>
+ * 				Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Tue Jun 26 14:36:48 MEST 2001 Herbert "herp" Rosmanith
+ *                               added netlink_proto_exit
+ * Tue Jan 22 18:32:44 BRST 2002 Arnaldo C. de Melo <acme@conectiva.com.br>
+ * 				 use nlk_sk, as sk->protinfo is on a diet 8)
+ * Fri Jul 22 19:51:12 MEST 2005 Harald Welte <laforge@gnumonks.org>
+ * 				 - inc module use count of module that owns
+ * 				   the kernel socket in case userspace opens
+ * 				   socket of same protocol
+ * 				 - remove all module support, since netlink is
+ * 				   mandatory if CONFIG_NET=y these days
+ */
+
+#include <linux/module.h>
+
+#include <linux/capability.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/stat.h>
+#include <linux/socket.h>
+#include <linux/un.h>
+#include <linux/fcntl.h>
+#include <linux/termios.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <asm/uaccess.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/notifier.h>
+#include <linux/security.h>
+#include <linux/jhash.h>
+#include <linux/jiffies.h>
+#include <linux/random.h>
+#include <linux/bitops.h>
+#include <linux/mm.h>
+#include <linux/types.h>
+#include <linux/audit.h>
+#include <linux/mutex.h>
+
+#include <net/net_namespace.h>
+#include <net/sock.h>
+#include <net/scm.h>
+#include <net/netlink.h>
+
+#define NLGRPSZ(x)	(ALIGN(x, sizeof(unsigned long) * 8) / 8)
+#define NLGRPLONGS(x)	(NLGRPSZ(x)/sizeof(unsigned long))
+
+struct netlink_sock {
+	/* struct sock has to be the first member of netlink_sock */
+	struct sock		sk;
+	u32			pid;
+	u32			dst_pid;
+	u32			dst_group;
+	u32			flags;
+	u32			subscriptions;
+	u32			ngroups;
+	unsigned long		*groups;
+	unsigned long		state;
+	wait_queue_head_t	wait;
+	struct netlink_callback	*cb;
+	struct mutex		*cb_mutex;
+	struct mutex		cb_def_mutex;
+	void			(*netlink_rcv)(struct sk_buff *skb);
+	struct module		*module;
+};
+
+struct listeners {
+	struct rcu_head		rcu;
+	unsigned long		masks[0];
+};
+
+#define NETLINK_KERNEL_SOCKET	0x1
+#define NETLINK_RECV_PKTINFO	0x2
+#define NETLINK_BROADCAST_SEND_ERROR	0x4
+#define NETLINK_RECV_NO_ENOBUFS	0x8
+
+/*add for the skb of netlink uevent*/
+#define NETLINK_ERR_SK			(1)
+#define	NETLINK_ERR_PID			(2)
+#define	NETLINK_ERR_NETEQ		(3)
+#define	NETLINK_ERR_PFAIL		(4)
+#define	NETLINK_ERR_SKB2		(5)
+#define	NETLINK_ERR_TXFILTER	(6)
+#define	NETLINK_ERR_SKFILTER	(7)
+#define	NETLINK_ERR_DELIVER		(8)
+
+volatile int g_test_netlink = 0;
+
+static inline struct netlink_sock *nlk_sk(struct sock *sk)
+{
+	return container_of(sk, struct netlink_sock, sk);
+}
+
+u32 mnl_get_pid(struct sock *sk)
+{
+	return nlk_sk(sk)->pid;
+}
+
+static inline int netlink_is_kernel(struct sock *sk)
+{
+	return nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET;
+}
+
+struct nl_pid_hash {
+	struct hlist_head *table;
+	unsigned long rehash_time;
+
+	unsigned int mask;
+	unsigned int shift;
+
+	unsigned int entries;
+	unsigned int max_shift;
+
+	u32 rnd;
+};
+
+struct netlink_table {
+	struct nl_pid_hash hash;
+	struct hlist_head mc_list;
+	struct listeners __rcu *listeners;
+	unsigned int nl_nonroot;
+	unsigned int groups;
+	struct mutex *cb_mutex;
+	struct module *module;
+	int registered;
+};
+
+static struct netlink_table *nl_table;
+
+static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait);
+
+static int netlink_dump(struct sock *sk);
+static void netlink_destroy_callback(struct netlink_callback *cb);
+
+static DEFINE_RWLOCK(nl_table_lock);
+static atomic_t nl_table_users = ATOMIC_INIT(0);
+
+#define nl_deref_protected(X) rcu_dereference_protected(X, lockdep_is_held(&nl_table_lock));
+
+static ATOMIC_NOTIFIER_HEAD(netlink_chain);
+
+static inline u32 netlink_group_mask(u32 group)
+{
+	return group ? 1 << (group - 1) : 0;
+}
+
+static inline struct hlist_head *nl_pid_hashfn(struct nl_pid_hash *hash, u32 pid)
+{
+	return &hash->table[jhash_1word(pid, hash->rnd) & hash->mask];
+}
+
+static void netlink_sock_destruct(struct sock *sk)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+
+	if (nlk->cb) {
+		if (nlk->cb->done)
+			nlk->cb->done(nlk->cb);
+
+		module_put(nlk->cb->module);
+		netlink_destroy_callback(nlk->cb);
+	}
+
+	skb_queue_purge(&sk->sk_receive_queue);
+
+	if (!sock_flag(sk, SOCK_DEAD)) {
+		printk(KERN_ERR "Freeing alive netlink socket %p\n", sk);
+		return;
+	}
+
+	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
+	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
+	WARN_ON(nlk_sk(sk)->groups);
+}
+
+/* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on
+ * SMP. Look, when several writers sleep and reader wakes them up, all but one
+ * immediately hit write lock and grab all the cpus. Exclusive sleep solves
+ * this, _but_ remember, it adds useless work on UP machines.
+ */
+
+void netlink_table_grab(void)
+	__acquires(nl_table_lock)
+{
+	might_sleep();
+
+	write_lock_irq(&nl_table_lock);
+
+	if (atomic_read(&nl_table_users)) {
+		DECLARE_WAITQUEUE(wait, current);
+
+		add_wait_queue_exclusive(&nl_table_wait, &wait);
+		for (;;) {
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			if (atomic_read(&nl_table_users) == 0)
+				break;
+			write_unlock_irq(&nl_table_lock);
+			schedule();
+			write_lock_irq(&nl_table_lock);
+		}
+
+		__set_current_state(TASK_RUNNING);
+		remove_wait_queue(&nl_table_wait, &wait);
+	}
+}
+
+void netlink_table_ungrab(void)
+	__releases(nl_table_lock)
+{
+	write_unlock_irq(&nl_table_lock);
+	wake_up(&nl_table_wait);
+}
+
+static inline void
+netlink_lock_table(void)
+{
+	/* read_lock() synchronizes us to netlink_table_grab */
+
+	read_lock(&nl_table_lock);
+	atomic_inc(&nl_table_users);
+	read_unlock(&nl_table_lock);
+}
+
+static inline void
+netlink_unlock_table(void)
+{
+	if (atomic_dec_and_test(&nl_table_users))
+		wake_up(&nl_table_wait);
+}
+
+static struct sock *netlink_lookup(struct net *net, int protocol, u32 pid)
+{
+	struct nl_pid_hash *hash = &nl_table[protocol].hash;
+	struct hlist_head *head;
+	struct sock *sk;
+	struct hlist_node *node;
+
+	read_lock(&nl_table_lock);
+	head = nl_pid_hashfn(hash, pid);
+	sk_for_each(sk, node, head) {
+		if (net_eq(sock_net(sk), net) && (nlk_sk(sk)->pid == pid)) {
+			sock_hold(sk);
+			goto found;
+		}
+	}
+	sk = NULL;
+found:
+	read_unlock(&nl_table_lock);
+	return sk;
+}
+
+static struct hlist_head *nl_pid_hash_zalloc(size_t size)
+{
+	if (size <= PAGE_SIZE)
+		return kzalloc(size, GFP_ATOMIC);
+	else
+		return (struct hlist_head *)
+			__get_free_pages(GFP_ATOMIC | __GFP_ZERO,
+					 get_order(size));
+}
+
+static void nl_pid_hash_free(struct hlist_head *table, size_t size)
+{
+	if (size <= PAGE_SIZE)
+		kfree(table);
+	else
+		free_pages((unsigned long)table, get_order(size));
+}
+
+static int nl_pid_hash_rehash(struct nl_pid_hash *hash, int grow)
+{
+	unsigned int omask, mask, shift;
+	size_t osize, size;
+	struct hlist_head *otable, *table;
+	int i;
+
+	omask = mask = hash->mask;
+	osize = size = (mask + 1) * sizeof(*table);
+	shift = hash->shift;
+
+	if (grow) {
+		if (++shift > hash->max_shift)
+			return 0;
+		mask = mask * 2 + 1;
+		size *= 2;
+	}
+
+	table = nl_pid_hash_zalloc(size);
+	if (!table)
+		return 0;
+
+	otable = hash->table;
+	hash->table = table;
+	hash->mask = mask;
+	hash->shift = shift;
+	get_random_bytes(&hash->rnd, sizeof(hash->rnd));
+
+	for (i = 0; i <= omask; i++) {
+		struct sock *sk;
+		struct hlist_node *node, *tmp;
+
+		sk_for_each_safe(sk, node, tmp, &otable[i])
+			__sk_add_node(sk, nl_pid_hashfn(hash, nlk_sk(sk)->pid));
+	}
+
+	nl_pid_hash_free(otable, osize);
+	hash->rehash_time = jiffies + 10 * 60 * HZ;
+	return 1;
+}
+
+static inline int nl_pid_hash_dilute(struct nl_pid_hash *hash, int len)
+{
+	int avg = hash->entries >> hash->shift;
+
+	if (unlikely(avg > 1) && nl_pid_hash_rehash(hash, 1))
+		return 1;
+
+	if (unlikely(len > avg) && time_after(jiffies, hash->rehash_time)) {
+		nl_pid_hash_rehash(hash, 0);
+		return 1;
+	}
+
+	return 0;
+}
+
+static const struct proto_ops netlink_ops;
+
+static void
+netlink_update_listeners(struct sock *sk)
+{
+	struct netlink_table *tbl = &nl_table[sk->sk_protocol];
+	struct hlist_node *node;
+	unsigned long mask;
+	unsigned int i;
+	struct listeners *listeners;
+
+	listeners = nl_deref_protected(tbl->listeners);
+	if (!listeners)
+		return;
+
+	for (i = 0; i < NLGRPLONGS(tbl->groups); i++) {
+		mask = 0;
+		sk_for_each_bound(sk, node, &tbl->mc_list) {
+			if (i < NLGRPLONGS(nlk_sk(sk)->ngroups))
+				mask |= nlk_sk(sk)->groups[i];
+		}
+		listeners->masks[i] = mask;
+	}
+	/* this function is only called with the netlink table "grabbed", which
+	 * makes sure updates are visible before bind or setsockopt return. */
+}
+
+static int netlink_insert(struct sock *sk, struct net *net, u32 pid)
+{
+	struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash;
+	struct hlist_head *head;
+	int err = -EADDRINUSE;
+	struct sock *osk;
+	struct hlist_node *node;
+	int len;
+
+	netlink_table_grab();
+	head = nl_pid_hashfn(hash, pid);
+	len = 0;
+	sk_for_each(osk, node, head) {
+		if (net_eq(sock_net(osk), net) && (nlk_sk(osk)->pid == pid))
+			break;
+		len++;
+	}
+	if (node)
+		goto err;
+
+	err = -EBUSY;
+	if (nlk_sk(sk)->pid)
+		goto err;
+
+	err = -ENOMEM;
+	if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX))
+		goto err;
+
+	if (len && nl_pid_hash_dilute(hash, len))
+		head = nl_pid_hashfn(hash, pid);
+	hash->entries++;
+	nlk_sk(sk)->pid = pid;
+	sk_add_node(sk, head);
+	err = 0;
+
+err:
+	netlink_table_ungrab();
+	return err;
+}
+
+static void netlink_remove(struct sock *sk)
+{
+	netlink_table_grab();
+	if (sk_del_node_init(sk))
+		nl_table[sk->sk_protocol].hash.entries--;
+	if (nlk_sk(sk)->subscriptions)
+		__sk_del_bind_node(sk);
+	netlink_table_ungrab();
+}
+
+static struct proto netlink_proto = {
+	.name	  = "NETLINK",
+	.owner	  = THIS_MODULE,
+	.obj_size = sizeof(struct netlink_sock),
+};
+
+static int __netlink_create(struct net *net, struct socket *sock,
+			    struct mutex *cb_mutex, int protocol)
+{
+	struct sock *sk;
+	struct netlink_sock *nlk;
+
+	sock->ops = &netlink_ops;
+
+	sk = sk_alloc(net, PF_NETLINK, GFP_KERNEL, &netlink_proto);
+	if (!sk)
+		return -ENOMEM;
+
+	sock_init_data(sock, sk);
+
+	nlk = nlk_sk(sk);
+	if (cb_mutex)
+		nlk->cb_mutex = cb_mutex;
+	else {
+		nlk->cb_mutex = &nlk->cb_def_mutex;
+		mutex_init(nlk->cb_mutex);
+	}
+	init_waitqueue_head(&nlk->wait);
+
+	sk->sk_destruct = netlink_sock_destruct;
+	sk->sk_protocol = protocol;
+	return 0;
+}
+
+static int netlink_create(struct net *net, struct socket *sock, int protocol,
+			  int kern)
+{
+	struct module *module = NULL;
+	struct mutex *cb_mutex;
+	struct netlink_sock *nlk;
+	int err = 0;
+
+	sock->state = SS_UNCONNECTED;
+
+	if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
+		return -ESOCKTNOSUPPORT;
+
+	if (protocol < 0 || protocol >= MAX_LINKS)
+		return -EPROTONOSUPPORT;
+
+	netlink_lock_table();
+#ifdef CONFIG_MODULES
+	if (!nl_table[protocol].registered) {
+		netlink_unlock_table();
+		request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol);
+		netlink_lock_table();
+	}
+#endif
+	if (nl_table[protocol].registered &&
+	    try_module_get(nl_table[protocol].module))
+		module = nl_table[protocol].module;
+	else
+		err = -EPROTONOSUPPORT;
+	cb_mutex = nl_table[protocol].cb_mutex;
+	netlink_unlock_table();
+
+	if (err < 0)
+		goto out;
+
+	err = __netlink_create(net, sock, cb_mutex, protocol);
+	if (err < 0)
+		goto out_module;
+
+	local_bh_disable();
+	sock_prot_inuse_add(net, &netlink_proto, 1);
+	local_bh_enable();
+
+	nlk = nlk_sk(sock->sk);
+	nlk->module = module;
+out:
+	return err;
+
+out_module:
+	module_put(module);
+	goto out;
+}
+
+static int netlink_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct netlink_sock *nlk;
+
+	if (!sk)
+		return 0;
+
+	netlink_remove(sk);
+	sock_orphan(sk);
+	nlk = nlk_sk(sk);
+
+	/*
+	 * OK. Socket is unlinked, any packets that arrive now
+	 * will be purged.
+	 */
+
+	sock->sk = NULL;
+	wake_up_interruptible_all(&nlk->wait);
+
+	skb_queue_purge(&sk->sk_write_queue);
+
+	if (nlk->pid) {
+		struct netlink_notify n = {
+						.net = sock_net(sk),
+						.protocol = sk->sk_protocol,
+						.pid = nlk->pid,
+					  };
+		atomic_notifier_call_chain(&netlink_chain,
+				NETLINK_URELEASE, &n);
+	}
+
+	module_put(nlk->module);
+
+	netlink_table_grab();
+	if (netlink_is_kernel(sk)) {
+		BUG_ON(nl_table[sk->sk_protocol].registered == 0);
+		if (--nl_table[sk->sk_protocol].registered == 0) {
+			struct listeners *old;
+
+			old = nl_deref_protected(nl_table[sk->sk_protocol].listeners);
+			RCU_INIT_POINTER(nl_table[sk->sk_protocol].listeners, NULL);
+			kfree_rcu(old, rcu);
+			nl_table[sk->sk_protocol].module = NULL;
+			nl_table[sk->sk_protocol].registered = 0;
+		}
+	} else if (nlk->subscriptions)
+		netlink_update_listeners(sk);
+	netlink_table_ungrab();
+
+	kfree(nlk->groups);
+	nlk->groups = NULL;
+
+	local_bh_disable();
+	sock_prot_inuse_add(sock_net(sk), &netlink_proto, -1);
+	local_bh_enable();
+	sock_put(sk);
+	return 0;
+}
+
+static int netlink_autobind(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct net *net = sock_net(sk);
+	struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash;
+	struct hlist_head *head;
+	struct sock *osk;
+	struct hlist_node *node;
+	s32 pid = task_tgid_vnr(current);
+	int err;
+	static s32 rover = -4097;
+
+retry:
+	cond_resched();
+	netlink_table_grab();
+	head = nl_pid_hashfn(hash, pid);
+	sk_for_each(osk, node, head) {
+		if (!net_eq(sock_net(osk), net))
+			continue;
+		if (nlk_sk(osk)->pid == pid) {
+			/* Bind collision, search negative pid values. */
+			pid = rover--;
+			if (rover > -4097)
+				rover = -4097;
+			netlink_table_ungrab();
+			goto retry;
+		}
+	}
+	netlink_table_ungrab();
+
+	err = netlink_insert(sk, net, pid);
+	if (err == -EADDRINUSE)
+		goto retry;
+
+	/* If 2 threads race to autobind, that is fine.  */
+	if (err == -EBUSY)
+		err = 0;
+
+	return err;
+}
+
+static inline int netlink_capable(const struct socket *sock, unsigned int flag)
+{
+	return (nl_table[sock->sk->sk_protocol].nl_nonroot & flag) ||
+	       capable(CAP_NET_ADMIN);
+}
+
+static void
+netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+
+	if (nlk->subscriptions && !subscriptions)
+		__sk_del_bind_node(sk);
+	else if (!nlk->subscriptions && subscriptions)
+		sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list);
+	nlk->subscriptions = subscriptions;
+}
+
+static int netlink_realloc_groups(struct sock *sk)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+	unsigned int groups;
+	unsigned long *new_groups;
+	int err = 0;
+
+	netlink_table_grab();
+
+	groups = nl_table[sk->sk_protocol].groups;
+	if (!nl_table[sk->sk_protocol].registered) {
+		err = -ENOENT;
+		goto out_unlock;
+	}
+
+	if (nlk->ngroups >= groups)
+		goto out_unlock;
+
+	new_groups = krealloc(nlk->groups, NLGRPSZ(groups), GFP_ATOMIC);
+	if (new_groups == NULL) {
+		err = -ENOMEM;
+		goto out_unlock;
+	}
+	memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0,
+	       NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups));
+
+	nlk->groups = new_groups;
+	nlk->ngroups = groups;
+ out_unlock:
+	netlink_table_ungrab();
+	return err;
+}
+
+static int netlink_bind(struct socket *sock, struct sockaddr *addr,
+			int addr_len)
+{
+	struct sock *sk = sock->sk;
+	struct net *net = sock_net(sk);
+	struct netlink_sock *nlk = nlk_sk(sk);
+	struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
+	int err;
+
+	if (nladdr->nl_family != AF_NETLINK)
+		return -EINVAL;
+
+	/* Only superuser is allowed to listen multicasts */
+	if (nladdr->nl_groups) {
+		if (!netlink_capable(sock, NL_NONROOT_RECV))
+			return -EPERM;
+		err = netlink_realloc_groups(sk);
+		if (err)
+			return err;
+	}
+
+	if (nlk->pid) {
+		if (nladdr->nl_pid != nlk->pid)
+			return -EINVAL;
+	} else {
+		err = nladdr->nl_pid ?
+			netlink_insert(sk, net, nladdr->nl_pid) :
+			netlink_autobind(sock);
+		if (err)
+			return err;
+	}
+
+	if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0]))
+		return 0;
+
+	netlink_table_grab();
+	netlink_update_subscriptions(sk, nlk->subscriptions +
+					 hweight32(nladdr->nl_groups) -
+					 hweight32(nlk->groups[0]));
+	nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups;
+	netlink_update_listeners(sk);
+	netlink_table_ungrab();
+
+	return 0;
+}
+
+static int netlink_connect(struct socket *sock, struct sockaddr *addr,
+			   int alen, int flags)
+{
+	int err = 0;
+	struct sock *sk = sock->sk;
+	struct netlink_sock *nlk = nlk_sk(sk);
+	struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
+
+	if (alen < sizeof(addr->sa_family))
+		return -EINVAL;
+
+	if (addr->sa_family == AF_UNSPEC) {
+		sk->sk_state	= NETLINK_UNCONNECTED;
+		nlk->dst_pid	= 0;
+		nlk->dst_group  = 0;
+		return 0;
+	}
+	if (addr->sa_family != AF_NETLINK)
+		return -EINVAL;
+
+	/* Only superuser is allowed to send multicasts */
+	if (nladdr->nl_groups && !netlink_capable(sock, NL_NONROOT_SEND))
+		return -EPERM;
+
+	if (!nlk->pid)
+		err = netlink_autobind(sock);
+
+	if (err == 0) {
+		sk->sk_state	= NETLINK_CONNECTED;
+		nlk->dst_pid 	= nladdr->nl_pid;
+		nlk->dst_group  = ffs(nladdr->nl_groups);
+	}
+
+	return err;
+}
+
+static int netlink_getname(struct socket *sock, struct sockaddr *addr,
+			   int *addr_len, int peer)
+{
+	struct sock *sk = sock->sk;
+	struct netlink_sock *nlk = nlk_sk(sk);
+	DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr);
+
+	nladdr->nl_family = AF_NETLINK;
+	nladdr->nl_pad = 0;
+	*addr_len = sizeof(*nladdr);
+
+	if (peer) {
+		nladdr->nl_pid = nlk->dst_pid;
+		nladdr->nl_groups = netlink_group_mask(nlk->dst_group);
+	} else {
+		nladdr->nl_pid = nlk->pid;
+		nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0;
+	}
+	return 0;
+}
+
+static void netlink_overrun(struct sock *sk)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+
+	if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) {
+		if (!test_and_set_bit(0, &nlk_sk(sk)->state)) {
+			sk->sk_err = ENOBUFS;
+			sk->sk_error_report(sk);
+		}
+	}
+	atomic_inc(&sk->sk_drops);
+}
+
+static struct sock *netlink_getsockbypid(struct sock *ssk, u32 pid)
+{
+	struct sock *sock;
+	struct netlink_sock *nlk;
+
+	sock = netlink_lookup(sock_net(ssk), ssk->sk_protocol, pid);
+	if (!sock)
+		return ERR_PTR(-ECONNREFUSED);
+
+	/* Don't bother queuing skb if kernel socket has no input function */
+	nlk = nlk_sk(sock);
+	if (sock->sk_state == NETLINK_CONNECTED &&
+	    nlk->dst_pid != nlk_sk(ssk)->pid) {
+		sock_put(sock);
+		return ERR_PTR(-ECONNREFUSED);
+	}
+	return sock;
+}
+
+struct sock *netlink_getsockbyfilp(struct file *filp)
+{
+	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct sock *sock;
+
+	if (!S_ISSOCK(inode->i_mode))
+		return ERR_PTR(-ENOTSOCK);
+
+	sock = SOCKET_I(inode)->sk;
+	if (sock->sk_family != AF_NETLINK)
+		return ERR_PTR(-EINVAL);
+
+	sock_hold(sock);
+	return sock;
+}
+
+/*
+ * Attach a skb to a netlink socket.
+ * The caller must hold a reference to the destination socket. On error, the
+ * reference is dropped. The skb is not send to the destination, just all
+ * all error checks are performed and memory in the queue is reserved.
+ * Return values:
+ * < 0: error. skb freed, reference to sock dropped.
+ * 0: continue
+ * 1: repeat lookup - reference dropped while waiting for socket memory.
+ */
+int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
+		      long *timeo, struct sock *ssk)
+{
+	struct netlink_sock *nlk;
+
+	nlk = nlk_sk(sk);
+
+	if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
+	    test_bit(0, &nlk->state)) {
+		DECLARE_WAITQUEUE(wait, current);
+		if (!*timeo) {
+			if (!ssk || netlink_is_kernel(ssk))
+				netlink_overrun(sk);
+			sock_put(sk);
+			kfree_skb(skb);
+			return -EAGAIN;
+		}
+
+		__set_current_state(TASK_INTERRUPTIBLE);
+		add_wait_queue(&nlk->wait, &wait);
+
+		if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
+		     test_bit(0, &nlk->state)) &&
+		    !sock_flag(sk, SOCK_DEAD))
+			*timeo = schedule_timeout(*timeo);
+
+		__set_current_state(TASK_RUNNING);
+		remove_wait_queue(&nlk->wait, &wait);
+		sock_put(sk);
+
+		if (signal_pending(current)) {
+			kfree_skb(skb);
+			return sock_intr_errno(*timeo);
+		}
+		return 1;
+	}
+	skb_set_owner_r(skb, sk);
+	return 0;
+}
+
+static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb)
+{
+	int len = skb->len;
+
+	skb_queue_tail(&sk->sk_receive_queue, skb);
+	sk->sk_data_ready(sk, len);
+	return len;
+}
+
+int netlink_sendskb(struct sock *sk, struct sk_buff *skb)
+{
+	int len = __netlink_sendskb(sk, skb);
+
+	sock_put(sk);
+	return len;
+}
+
+void netlink_detachskb(struct sock *sk, struct sk_buff *skb)
+{
+	kfree_skb(skb);
+	sock_put(sk);
+}
+
+static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation)
+{
+	int delta;
+
+	skb_orphan(skb);
+
+	delta = skb->end - skb->tail;
+	if (delta * 2 < skb->truesize)
+		return skb;
+
+	if (skb_shared(skb)) {
+		struct sk_buff *nskb = skb_clone(skb, allocation);
+		if (!nskb)
+			return skb;
+		kfree_skb(skb);
+		skb = nskb;
+	}
+
+	if (!pskb_expand_head(skb, 0, -delta, allocation))
+		skb->truesize -= delta;
+
+	return skb;
+}
+
+static void netlink_rcv_wake(struct sock *sk)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+
+	if (skb_queue_empty(&sk->sk_receive_queue))
+		clear_bit(0, &nlk->state);
+	if (!test_bit(0, &nlk->state))
+		wake_up_interruptible(&nlk->wait);
+}
+
+static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb)
+{
+	int ret;
+	struct netlink_sock *nlk = nlk_sk(sk);
+
+	ret = -ECONNREFUSED;
+	if (nlk->netlink_rcv != NULL) {
+		ret = skb->len;
+		skb_set_owner_r(skb, sk);
+		nlk->netlink_rcv(skb);
+	}
+	kfree_skb(skb);
+	sock_put(sk);
+	return ret;
+}
+
+int netlink_unicast(struct sock *ssk, struct sk_buff *skb,
+		    u32 pid, int nonblock)
+{
+	struct sock *sk;
+	int err;
+	long timeo;
+	track_netlink(skb,0);
+	skb = netlink_trim(skb, gfp_any());
+
+	timeo = sock_sndtimeo(ssk, nonblock);
+retry:
+	sk = netlink_getsockbypid(ssk, pid);
+	if (IS_ERR(sk)) {
+		kfree_skb(skb);
+		return PTR_ERR(sk);
+	}
+	if (netlink_is_kernel(sk))
+		return netlink_unicast_kernel(sk, skb);
+
+	if (sk_filter(sk, skb)) {
+		err = skb->len;
+		kfree_skb(skb);
+		sock_put(sk);
+		return err;
+	}
+
+	err = netlink_attachskb(sk, skb, &timeo, ssk);
+	if (err == 1)
+		goto retry;
+	if (err)
+		return err;
+
+	return netlink_sendskb(sk, skb);
+}
+EXPORT_SYMBOL(netlink_unicast);
+
+int netlink_has_listeners(struct sock *sk, unsigned int group)
+{
+	int res = 0;
+	struct listeners *listeners;
+
+	BUG_ON(!netlink_is_kernel(sk));
+
+	rcu_read_lock();
+	listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners);
+
+	if (listeners && group - 1 < nl_table[sk->sk_protocol].groups)
+		res = test_bit(group - 1, listeners->masks);
+
+	rcu_read_unlock();
+
+	return res;
+}
+EXPORT_SYMBOL_GPL(netlink_has_listeners);
+
+static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+
+	if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf &&
+	    !test_bit(0, &nlk->state)) {
+		skb_set_owner_r(skb, sk);
+		__netlink_sendskb(sk, skb);
+		return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
+	}
+	return -1;
+}
+
+struct netlink_broadcast_data {
+	struct sock *exclude_sk;
+	struct net *net;
+	u32 pid;
+	u32 group;
+	int failure;
+	int delivery_failure;
+	int congested;
+	int delivered;
+	gfp_t allocation;
+	struct sk_buff *skb, *skb2;
+	int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data);
+	void *tx_data;
+};
+
+static int do_one_broadcast(struct sock *sk,
+				   struct netlink_broadcast_data *p)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+	int val;
+
+	if (p->exclude_sk == sk) {
+		g_test_netlink = NETLINK_ERR_SK;
+		goto out;
+		
+	}
+	if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups ||
+	    !test_bit(p->group - 1, nlk->groups)) {
+		g_test_netlink = NETLINK_ERR_PID;
+		goto out;
+	}
+	if (!net_eq(sock_net(sk), p->net)) {
+		g_test_netlink = NETLINK_ERR_NETEQ;
+		goto out;
+	}
+	if (p->failure) {
+		netlink_overrun(sk);
+		g_test_netlink = NETLINK_ERR_PFAIL;
+		goto out;
+	}
+
+	sock_hold(sk);
+	if (p->skb2 == NULL) {
+		if (skb_shared(p->skb)) {
+			p->skb2 = skb_clone(p->skb, p->allocation);
+		} else {
+			p->skb2 = skb_get(p->skb);
+			/*
+			 * skb ownership may have been set when
+			 * delivered to a previous socket.
+			 */
+			skb_orphan(p->skb2);
+		}
+	}
+	if (p->skb2 == NULL) {
+		netlink_overrun(sk);
+		/* Clone failed. Notify ALL listeners. */
+		p->failure = 1;
+		if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR)
+			p->delivery_failure = 1;
+		g_test_netlink = NETLINK_ERR_SKB2;
+	} else if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) {
+		kfree_skb(p->skb2);
+		p->skb2 = NULL;
+		g_test_netlink = NETLINK_ERR_TXFILTER;
+	} else if (sk_filter(sk, p->skb2)) {
+		kfree_skb(p->skb2);
+		p->skb2 = NULL;
+		g_test_netlink = NETLINK_ERR_SKFILTER;
+	} else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) {
+		netlink_overrun(sk);
+		if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR)
+			p->delivery_failure = 1;
+		g_test_netlink = NETLINK_ERR_DELIVER;;
+	} else {
+		p->congested |= val;
+		p->delivered = 1;
+		p->skb2 = NULL;
+	}
+	sock_put(sk);
+
+out:
+	return 0;
+}
+
+int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 pid,
+	u32 group, gfp_t allocation,
+	int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
+	void *filter_data)
+{
+	struct net *net = sock_net(ssk);
+	struct netlink_broadcast_data info;
+	struct hlist_node *node;
+	struct sock *sk;
+
+	track_netlink(skb,group);
+	skb = netlink_trim(skb, allocation);
+
+	info.exclude_sk = ssk;
+	info.net = net;
+	info.pid = pid;
+	info.group = group;
+	info.failure = 0;
+	info.delivery_failure = 0;
+	info.congested = 0;
+	info.delivered = 0;
+	info.allocation = allocation;
+	info.skb = skb;
+	info.skb2 = NULL;
+	info.tx_filter = filter;
+	info.tx_data = filter_data;
+
+	/* While we sleep in clone, do not allow to change socket list */
+
+	netlink_lock_table();
+
+	sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
+		do_one_broadcast(sk, &info);
+
+	consume_skb(skb);
+
+	netlink_unlock_table();
+
+	if (info.delivery_failure) {
+		kfree_skb(info.skb2);
+		return -ENOBUFS;
+	} else
+		consume_skb(info.skb2);
+
+	if (info.delivered) {
+		if (info.congested && (allocation & __GFP_WAIT))
+			yield();
+		return 0;
+	}
+	return -ESRCH;
+}
+EXPORT_SYMBOL(netlink_broadcast_filtered);
+
+int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid,
+		      u32 group, gfp_t allocation)
+{
+	return netlink_broadcast_filtered(ssk, skb, pid, group, allocation,
+		NULL, NULL);
+}
+EXPORT_SYMBOL(netlink_broadcast);
+
+struct netlink_set_err_data {
+	struct sock *exclude_sk;
+	u32 pid;
+	u32 group;
+	int code;
+};
+
+static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+	int ret = 0;
+
+	if (sk == p->exclude_sk)
+		goto out;
+
+	if (!net_eq(sock_net(sk), sock_net(p->exclude_sk)))
+		goto out;
+
+	if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups ||
+	    !test_bit(p->group - 1, nlk->groups))
+		goto out;
+
+	if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) {
+		ret = 1;
+		goto out;
+	}
+
+	sk->sk_err = p->code;
+	sk->sk_error_report(sk);
+out:
+	return ret;
+}
+
+/**
+ * netlink_set_err - report error to broadcast listeners
+ * @ssk: the kernel netlink socket, as returned by netlink_kernel_create()
+ * @pid: the PID of a process that we want to skip (if any)
+ * @groups: the broadcast group that will notice the error
+ * @code: error code, must be negative (as usual in kernelspace)
+ *
+ * This function returns the number of broadcast listeners that have set the
+ * NETLINK_RECV_NO_ENOBUFS socket option.
+ */
+int netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code)
+{
+	struct netlink_set_err_data info;
+	struct hlist_node *node;
+	struct sock *sk;
+	int ret = 0;
+
+	info.exclude_sk = ssk;
+	info.pid = pid;
+	info.group = group;
+	/* sk->sk_err wants a positive error value */
+	info.code = -code;
+
+	read_lock(&nl_table_lock);
+
+	sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
+		ret += do_one_set_err(sk, &info);
+
+	read_unlock(&nl_table_lock);
+	return ret;
+}
+EXPORT_SYMBOL(netlink_set_err);
+
+/* must be called with netlink table grabbed */
+static void netlink_update_socket_mc(struct netlink_sock *nlk,
+				     unsigned int group,
+				     int is_new)
+{
+	int old, new = !!is_new, subscriptions;
+
+	old = test_bit(group - 1, nlk->groups);
+	subscriptions = nlk->subscriptions - old + new;
+	if (new)
+		__set_bit(group - 1, nlk->groups);
+	else
+		__clear_bit(group - 1, nlk->groups);
+	netlink_update_subscriptions(&nlk->sk, subscriptions);
+	netlink_update_listeners(&nlk->sk);
+}
+
+static int netlink_setsockopt(struct socket *sock, int level, int optname,
+			      char __user *optval, unsigned int optlen)
+{
+	struct sock *sk = sock->sk;
+	struct netlink_sock *nlk = nlk_sk(sk);
+	unsigned int val = 0;
+	int err;
+
+	if (level != SOL_NETLINK)
+		return -ENOPROTOOPT;
+
+	if (optlen >= sizeof(int) &&
+	    get_user(val, (unsigned int __user *)optval))
+		return -EFAULT;
+
+	switch (optname) {
+	case NETLINK_PKTINFO:
+		if (val)
+			nlk->flags |= NETLINK_RECV_PKTINFO;
+		else
+			nlk->flags &= ~NETLINK_RECV_PKTINFO;
+		err = 0;
+		break;
+	case NETLINK_ADD_MEMBERSHIP:
+	case NETLINK_DROP_MEMBERSHIP: {
+		if (!netlink_capable(sock, NL_NONROOT_RECV))
+			return -EPERM;
+		err = netlink_realloc_groups(sk);
+		if (err)
+			return err;
+		if (!val || val - 1 >= nlk->ngroups)
+			return -EINVAL;
+		netlink_table_grab();
+		netlink_update_socket_mc(nlk, val,
+					 optname == NETLINK_ADD_MEMBERSHIP);
+		netlink_table_ungrab();
+		err = 0;
+		break;
+	}
+	case NETLINK_BROADCAST_ERROR:
+		if (val)
+			nlk->flags |= NETLINK_BROADCAST_SEND_ERROR;
+		else
+			nlk->flags &= ~NETLINK_BROADCAST_SEND_ERROR;
+		err = 0;
+		break;
+	case NETLINK_NO_ENOBUFS:
+		if (val) {
+			nlk->flags |= NETLINK_RECV_NO_ENOBUFS;
+			clear_bit(0, &nlk->state);
+			wake_up_interruptible(&nlk->wait);
+		} else
+			nlk->flags &= ~NETLINK_RECV_NO_ENOBUFS;
+		err = 0;
+		break;
+	default:
+		err = -ENOPROTOOPT;
+	}
+	return err;
+}
+
+static int netlink_getsockopt(struct socket *sock, int level, int optname,
+			      char __user *optval, int __user *optlen)
+{
+	struct sock *sk = sock->sk;
+	struct netlink_sock *nlk = nlk_sk(sk);
+	int len, val, err;
+
+	if (level != SOL_NETLINK)
+		return -ENOPROTOOPT;
+
+	if (get_user(len, optlen))
+		return -EFAULT;
+	if (len < 0)
+		return -EINVAL;
+
+	switch (optname) {
+	case NETLINK_PKTINFO:
+		if (len < sizeof(int))
+			return -EINVAL;
+		len = sizeof(int);
+		val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0;
+		if (put_user(len, optlen) ||
+		    put_user(val, optval))
+			return -EFAULT;
+		err = 0;
+		break;
+	case NETLINK_BROADCAST_ERROR:
+		if (len < sizeof(int))
+			return -EINVAL;
+		len = sizeof(int);
+		val = nlk->flags & NETLINK_BROADCAST_SEND_ERROR ? 1 : 0;
+		if (put_user(len, optlen) ||
+		    put_user(val, optval))
+			return -EFAULT;
+		err = 0;
+		break;
+	case NETLINK_NO_ENOBUFS:
+		if (len < sizeof(int))
+			return -EINVAL;
+		len = sizeof(int);
+		val = nlk->flags & NETLINK_RECV_NO_ENOBUFS ? 1 : 0;
+		if (put_user(len, optlen) ||
+		    put_user(val, optval))
+			return -EFAULT;
+		err = 0;
+		break;
+	default:
+		err = -ENOPROTOOPT;
+	}
+	return err;
+}
+
+static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
+{
+	struct nl_pktinfo info;
+
+	info.group = NETLINK_CB(skb).dst_group;
+	put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info);
+}
+
+static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
+			   struct msghdr *msg, size_t len)
+{
+	struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
+	struct sock *sk = sock->sk;
+	struct netlink_sock *nlk = nlk_sk(sk);
+	struct sockaddr_nl *addr = msg->msg_name;
+	u32 dst_pid;
+	u32 dst_group;
+	struct sk_buff *skb;
+	int err;
+	struct scm_cookie scm;
+
+	if (msg->msg_flags&MSG_OOB)
+		return -EOPNOTSUPP;
+
+	if (NULL == siocb->scm)
+		siocb->scm = &scm;
+
+	err = scm_send(sock, msg, siocb->scm, true);
+	if (err < 0)
+		return err;
+
+	if (msg->msg_namelen) {
+		err = -EINVAL;
+		if (addr->nl_family != AF_NETLINK)
+			goto out;
+		dst_pid = addr->nl_pid;
+		dst_group = ffs(addr->nl_groups);
+		err =  -EPERM;
+		if ((dst_group || dst_pid) &&
+		    !netlink_capable(sock, NL_NONROOT_SEND))
+			goto out;
+	} else {
+		dst_pid = nlk->dst_pid;
+		dst_group = nlk->dst_group;
+	}
+
+	if (!nlk->pid) {
+		err = netlink_autobind(sock);
+		if (err)
+			goto out;
+	}
+
+	err = -EMSGSIZE;
+	if (len > sk->sk_sndbuf - 32)
+		goto out;
+	err = -ENOBUFS;
+	skb = alloc_skb(len, GFP_KERNEL);
+	if (skb == NULL)
+		goto out;
+
+	NETLINK_CB(skb).pid	= nlk->pid;
+	NETLINK_CB(skb).dst_group = dst_group;
+	memcpy(NETLINK_CREDS(skb), &siocb->scm->creds, sizeof(struct ucred));
+
+	err = -EFAULT;
+	if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
+		kfree_skb(skb);
+		goto out;
+	}
+
+	err = security_netlink_send(sk, skb);
+	if (err) {
+		kfree_skb(skb);
+		goto out;
+	}
+
+	if (dst_group) {
+		atomic_inc(&skb->users);
+		track_add(skb, 0, USER_INFO, 0);
+		netlink_broadcast(sk, skb, dst_pid, dst_group, GFP_KERNEL);
+	}
+	err = netlink_unicast(sk, skb, dst_pid, msg->msg_flags&MSG_DONTWAIT);
+
+out:
+	scm_destroy(siocb->scm);
+	return err;
+}
+
+static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
+			   struct msghdr *msg, size_t len,
+			   int flags)
+{
+	struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
+	struct scm_cookie scm;
+	struct sock *sk = sock->sk;
+	struct netlink_sock *nlk = nlk_sk(sk);
+	int noblock = flags&MSG_DONTWAIT;
+	size_t copied;
+	struct sk_buff *skb, *data_skb;
+	int err, ret;
+
+	if (flags&MSG_OOB)
+		return -EOPNOTSUPP;
+
+	copied = 0;
+
+	skb = skb_recv_datagram(sk, flags, noblock, &err);
+	if (skb == NULL)
+		goto out;
+
+	data_skb = skb;
+
+#ifdef CONFIG_COMPAT_NETLINK_MESSAGES
+	if (unlikely(skb_shinfo(skb)->frag_list)) {
+		/*
+		 * If this skb has a frag_list, then here that means that we
+		 * will have to use the frag_list skb's data for compat tasks
+		 * and the regular skb's data for normal (non-compat) tasks.
+		 *
+		 * If we need to send the compat skb, assign it to the
+		 * 'data_skb' variable so that it will be used below for data
+		 * copying. We keep 'skb' for everything else, including
+		 * freeing both later.
+		 */
+		if (flags & MSG_CMSG_COMPAT)
+			data_skb = skb_shinfo(skb)->frag_list;
+	}
+#endif
+
+	copied = data_skb->len;
+	if (len < copied) {
+		msg->msg_flags |= MSG_TRUNC;
+		copied = len;
+	}
+
+	skb_reset_transport_header(data_skb);
+	err = skb_copy_datagram_iovec(data_skb, 0, msg->msg_iov, copied);
+
+	if (msg->msg_name) {
+		struct sockaddr_nl *addr = (struct sockaddr_nl *)msg->msg_name;
+		addr->nl_family = AF_NETLINK;
+		addr->nl_pad    = 0;
+		addr->nl_pid	= NETLINK_CB(skb).pid;
+		addr->nl_groups	= netlink_group_mask(NETLINK_CB(skb).dst_group);
+		msg->msg_namelen = sizeof(*addr);
+	}
+
+	if (nlk->flags & NETLINK_RECV_PKTINFO)
+		netlink_cmsg_recv_pktinfo(msg, skb);
+
+	if (NULL == siocb->scm) {
+		memset(&scm, 0, sizeof(scm));
+		siocb->scm = &scm;
+	}
+	siocb->scm->creds = *NETLINK_CREDS(skb);
+	if (flags & MSG_TRUNC)
+		copied = data_skb->len;
+
+	skb_free_datagram(sk, skb);
+
+	if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
+		ret = netlink_dump(sk);
+		if (ret) {
+			sk->sk_err = ret;
+			sk->sk_error_report(sk);
+		}
+	}
+
+	scm_recv(sock, msg, siocb->scm, flags);
+out:
+	netlink_rcv_wake(sk);
+	return err ? : copied;
+}
+
+static void netlink_data_ready(struct sock *sk, int len)
+{
+	BUG();
+}
+
+/*
+ *	We export these functions to other modules. They provide a
+ *	complete set of kernel non-blocking support for message
+ *	queueing.
+ */
+
+struct sock *
+netlink_kernel_create(struct net *net, int unit, unsigned int groups,
+		      void (*input)(struct sk_buff *skb),
+		      struct mutex *cb_mutex, struct module *module)
+{
+	struct socket *sock;
+	struct sock *sk;
+	struct netlink_sock *nlk;
+	struct listeners *listeners = NULL;
+
+	BUG_ON(!nl_table);
+
+	if (unit < 0 || unit >= MAX_LINKS)
+		return NULL;
+
+	if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock))
+		return NULL;
+
+	/*
+	 * We have to just have a reference on the net from sk, but don't
+	 * get_net it. Besides, we cannot get and then put the net here.
+	 * So we create one inside init_net and the move it to net.
+	 */
+
+	if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0)
+		goto out_sock_release_nosk;
+
+	sk = sock->sk;
+	sk_change_net(sk, net);
+
+	if (groups < 32)
+		groups = 32;
+
+	listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL);
+	if (!listeners)
+		goto out_sock_release;
+
+	sk->sk_data_ready = netlink_data_ready;
+	if (input)
+		nlk_sk(sk)->netlink_rcv = input;
+
+	if (netlink_insert(sk, net, 0))
+		goto out_sock_release;
+
+	nlk = nlk_sk(sk);
+	nlk->flags |= NETLINK_KERNEL_SOCKET;
+
+	netlink_table_grab();
+	if (!nl_table[unit].registered) {
+		nl_table[unit].groups = groups;
+		rcu_assign_pointer(nl_table[unit].listeners, listeners);
+		nl_table[unit].cb_mutex = cb_mutex;
+		nl_table[unit].module = module;
+		nl_table[unit].registered = 1;
+	} else {
+		kfree(listeners);
+		nl_table[unit].registered++;
+	}
+	netlink_table_ungrab();
+	return sk;
+
+out_sock_release:
+	kfree(listeners);
+	netlink_kernel_release(sk);
+	return NULL;
+
+out_sock_release_nosk:
+	sock_release(sock);
+	return NULL;
+}
+EXPORT_SYMBOL(netlink_kernel_create);
+
+
+void
+netlink_kernel_release(struct sock *sk)
+{
+	sk_release_kernel(sk);
+}
+EXPORT_SYMBOL(netlink_kernel_release);
+
+int __netlink_change_ngroups(struct sock *sk, unsigned int groups)
+{
+	struct listeners *new, *old;
+	struct netlink_table *tbl = &nl_table[sk->sk_protocol];
+
+	if (groups < 32)
+		groups = 32;
+
+	if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) {
+		new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC);
+		if (!new)
+			return -ENOMEM;
+		old = nl_deref_protected(tbl->listeners);
+		memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups));
+		rcu_assign_pointer(tbl->listeners, new);
+
+		kfree_rcu(old, rcu);
+	}
+	tbl->groups = groups;
+
+	return 0;
+}
+
+/**
+ * netlink_change_ngroups - change number of multicast groups
+ *
+ * This changes the number of multicast groups that are available
+ * on a certain netlink family. Note that it is not possible to
+ * change the number of groups to below 32. Also note that it does
+ * not implicitly call netlink_clear_multicast_users() when the
+ * number of groups is reduced.
+ *
+ * @sk: The kernel netlink socket, as returned by netlink_kernel_create().
+ * @groups: The new number of groups.
+ */
+int netlink_change_ngroups(struct sock *sk, unsigned int groups)
+{
+	int err;
+
+	netlink_table_grab();
+	err = __netlink_change_ngroups(sk, groups);
+	netlink_table_ungrab();
+
+	return err;
+}
+
+void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
+{
+	struct sock *sk;
+	struct hlist_node *node;
+	struct netlink_table *tbl = &nl_table[ksk->sk_protocol];
+
+	sk_for_each_bound(sk, node, &tbl->mc_list)
+		netlink_update_socket_mc(nlk_sk(sk), group, 0);
+}
+
+/**
+ * netlink_clear_multicast_users - kick off multicast listeners
+ *
+ * This function removes all listeners from the given group.
+ * @ksk: The kernel netlink socket, as returned by
+ *	netlink_kernel_create().
+ * @group: The multicast group to clear.
+ */
+void netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
+{
+	netlink_table_grab();
+	__netlink_clear_multicast_users(ksk, group);
+	netlink_table_ungrab();
+}
+
+void netlink_set_nonroot(int protocol, unsigned int flags)
+{
+	if ((unsigned int)protocol < MAX_LINKS)
+		nl_table[protocol].nl_nonroot = flags;
+}
+EXPORT_SYMBOL(netlink_set_nonroot);
+
+static void netlink_destroy_callback(struct netlink_callback *cb)
+{
+	kfree_skb(cb->skb);
+	kfree(cb);
+}
+
+struct nlmsghdr *
+__nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags)
+{
+	struct nlmsghdr *nlh;
+	int size = NLMSG_LENGTH(len);
+
+	nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
+	nlh->nlmsg_type = type;
+	nlh->nlmsg_len = size;
+	nlh->nlmsg_flags = flags;
+	nlh->nlmsg_pid = pid;
+	nlh->nlmsg_seq = seq;
+	if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0)
+		memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
+	return nlh;
+}
+EXPORT_SYMBOL(__nlmsg_put);
+
+/*
+ * It looks a bit ugly.
+ * It would be better to create kernel thread.
+ */
+
+static int netlink_dump(struct sock *sk)
+{
+	struct netlink_sock *nlk = nlk_sk(sk);
+	struct netlink_callback *cb;
+	struct sk_buff *skb = NULL;
+	struct nlmsghdr *nlh;
+	int len, err = -ENOBUFS;
+	int alloc_size;
+	struct module		*module;
+	struct sk_buff		*skb2;
+
+	mutex_lock(nlk->cb_mutex);
+
+	cb = nlk->cb;
+	if (cb == NULL) {
+		err = -EINVAL;
+		goto errout_skb;
+	}
+
+	alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE);
+
+	skb = sock_rmalloc(sk, alloc_size, 0, GFP_KERNEL);
+	if (!skb)
+		goto errout_skb;
+
+	len = cb->dump(skb, cb);
+
+	if (len > 0) {
+		mutex_unlock(nlk->cb_mutex);
+
+		if (sk_filter(sk, skb))
+			kfree_skb(skb);
+		else
+			__netlink_sendskb(sk, skb);
+		return 0;
+	}
+
+	nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI);
+	if (!nlh)
+		goto errout_skb;
+
+	nl_dump_check_consistent(cb, nlh);
+
+	memcpy(nlmsg_data(nlh), &len, sizeof(len));
+
+	if (sk_filter(sk, skb))
+		kfree_skb(skb);
+	else
+		__netlink_sendskb(sk, skb);
+
+	if (cb->done)
+		cb->done(cb);
+	nlk->cb = NULL;
+
+	module = cb->module;
+	skb2 = cb->skb;
+	mutex_unlock(nlk->cb_mutex);
+
+	module_put(module);
+	kfree_skb(skb2);
+	kfree(cb);
+	return 0;
+
+errout_skb:
+	mutex_unlock(nlk->cb_mutex);
+	kfree_skb(skb);
+	return err;
+}
+
+int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
+			 const struct nlmsghdr *nlh,
+			 struct netlink_dump_control *control)
+{
+	struct netlink_callback *cb;
+	struct sock *sk;
+	struct netlink_sock *nlk;
+	int ret;
+
+	cb = kzalloc(sizeof(*cb), GFP_KERNEL);
+	if (cb == NULL)
+		return -ENOBUFS;
+
+	cb->dump = control->dump;
+	cb->done = control->done;
+	cb->nlh = nlh;
+	cb->data = control->data;
+	cb->module = control->module;
+	cb->min_dump_alloc = control->min_dump_alloc;
+	atomic_inc(&skb->users);
+	track_add(skb, 0, USER_INFO, 0);
+	cb->skb = skb;
+
+	sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).pid);
+	if (sk == NULL) {
+		netlink_destroy_callback(cb);
+		return -ECONNREFUSED;
+	}
+	nlk = nlk_sk(sk);
+
+	mutex_lock(nlk->cb_mutex);
+	/* A dump is in progress... */
+	if (nlk->cb) {
+		mutex_unlock(nlk->cb_mutex);
+		netlink_destroy_callback(cb);
+		ret = -EBUSY;
+		goto out;
+	}
+	/* add reference of module which cb->dump belongs to */
+	if (!try_module_get(cb->module)) {
+		mutex_unlock(nlk->cb_mutex);
+		netlink_destroy_callback(cb);
+		ret = -EPROTONOSUPPORT;
+		goto out;
+	}
+
+	nlk->cb = cb;
+	mutex_unlock(nlk->cb_mutex);
+
+	ret = netlink_dump(sk);
+out:
+	sock_put(sk);
+
+	if (ret)
+		return ret;
+
+	/* We successfully started a dump, by returning -EINTR we
+	 * signal not to send ACK even if it was requested.
+	 */
+	return -EINTR;
+}
+EXPORT_SYMBOL(__netlink_dump_start);
+
+void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
+{
+	struct sk_buff *skb;
+	struct nlmsghdr *rep;
+	struct nlmsgerr *errmsg;
+	size_t payload = sizeof(*errmsg);
+
+	/* error messages get the original request appened */
+	if (err)
+		payload += nlmsg_len(nlh);
+
+	skb = nlmsg_new(payload, GFP_KERNEL);
+	if (!skb) {
+		struct sock *sk;
+
+		sk = netlink_lookup(sock_net(in_skb->sk),
+				    in_skb->sk->sk_protocol,
+				    NETLINK_CB(in_skb).pid);
+		if (sk) {
+			sk->sk_err = ENOBUFS;
+			sk->sk_error_report(sk);
+			sock_put(sk);
+		}
+		return;
+	}
+
+	rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
+			  NLMSG_ERROR, payload, 0);
+	errmsg = nlmsg_data(rep);
+	errmsg->error = err;
+	memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh));
+	netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
+}
+EXPORT_SYMBOL(netlink_ack);
+
+int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *,
+						     struct nlmsghdr *))
+{
+	struct nlmsghdr *nlh;
+	int err;
+
+	while (skb->len >= nlmsg_total_size(0)) {
+		int msglen;
+
+		nlh = nlmsg_hdr(skb);
+		err = 0;
+
+		if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len)
+			return 0;
+
+		/* Only requests are handled by the kernel */
+		if (!(nlh->nlmsg_flags & NLM_F_REQUEST))
+			goto ack;
+
+		/* Skip control messages */
+		if (nlh->nlmsg_type < NLMSG_MIN_TYPE)
+			goto ack;
+
+		err = cb(skb, nlh);
+		if (err == -EINTR)
+			goto skip;
+
+ack:
+		if (nlh->nlmsg_flags & NLM_F_ACK || err)
+			netlink_ack(skb, nlh, err);
+
+skip:
+		msglen = NLMSG_ALIGN(nlh->nlmsg_len);
+		if (msglen > skb->len)
+			msglen = skb->len;
+		skb_pull(skb, msglen);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(netlink_rcv_skb);
+
+/**
+ * nlmsg_notify - send a notification netlink message
+ * @sk: netlink socket to use
+ * @skb: notification message
+ * @pid: destination netlink pid for reports or 0
+ * @group: destination multicast group or 0
+ * @report: 1 to report back, 0 to disable
+ * @flags: allocation flags
+ */
+int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 pid,
+		 unsigned int group, int report, gfp_t flags)
+{
+	int err = 0;
+
+	if (group) {
+		int exclude_pid = 0;
+
+		if (report) {
+            track_add(skb, 0, USER_INFO, 0);
+			atomic_inc(&skb->users);
+			exclude_pid = pid;
+		}
+
+		/* errors reported via destination sk->sk_err, but propagate
+		 * delivery errors if NETLINK_BROADCAST_ERROR flag is set */
+		err = nlmsg_multicast(sk, skb, exclude_pid, group, flags);
+	}
+
+	if (report) {
+		int err2;
+
+		err2 = nlmsg_unicast(sk, skb, pid);
+		if (!err || err == -ESRCH)
+			err = err2;
+	}
+
+	return err;
+}
+EXPORT_SYMBOL(nlmsg_notify);
+
+#ifdef CONFIG_PROC_FS
+struct nl_seq_iter {
+	struct seq_net_private p;
+	int link;
+	int hash_idx;
+};
+
+static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos)
+{
+	struct nl_seq_iter *iter = seq->private;
+	int i, j;
+	struct sock *s;
+	struct hlist_node *node;
+	loff_t off = 0;
+
+	for (i = 0; i < MAX_LINKS; i++) {
+		struct nl_pid_hash *hash = &nl_table[i].hash;
+
+		for (j = 0; j <= hash->mask; j++) {
+			sk_for_each(s, node, &hash->table[j]) {
+				if (sock_net(s) != seq_file_net(seq))
+					continue;
+				if (off == pos) {
+					iter->link = i;
+					iter->hash_idx = j;
+					return s;
+				}
+				++off;
+			}
+		}
+	}
+	return NULL;
+}
+
+static void *netlink_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(nl_table_lock)
+{
+	read_lock(&nl_table_lock);
+	return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN;
+}
+
+static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct sock *s;
+	struct nl_seq_iter *iter;
+	int i, j;
+
+	++*pos;
+
+	if (v == SEQ_START_TOKEN)
+		return netlink_seq_socket_idx(seq, 0);
+
+	iter = seq->private;
+	s = v;
+	do {
+		s = sk_next(s);
+	} while (s && sock_net(s) != seq_file_net(seq));
+	if (s)
+		return s;
+
+	i = iter->link;
+	j = iter->hash_idx + 1;
+
+	do {
+		struct nl_pid_hash *hash = &nl_table[i].hash;
+
+		for (; j <= hash->mask; j++) {
+			s = sk_head(&hash->table[j]);
+			while (s && sock_net(s) != seq_file_net(seq))
+				s = sk_next(s);
+			if (s) {
+				iter->link = i;
+				iter->hash_idx = j;
+				return s;
+			}
+		}
+
+		j = 0;
+	} while (++i < MAX_LINKS);
+
+	return NULL;
+}
+
+static void netlink_seq_stop(struct seq_file *seq, void *v)
+	__releases(nl_table_lock)
+{
+	read_unlock(&nl_table_lock);
+}
+
+
+static int netlink_seq_show(struct seq_file *seq, void *v)
+{
+	if (v == SEQ_START_TOKEN)
+		seq_puts(seq,
+			 "sk       Eth Pid    Groups   "
+			 "Rmem     Wmem     Dump     Locks     Drops     Inode\n");
+	else {
+		struct sock *s = v;
+		struct netlink_sock *nlk = nlk_sk(s);
+
+		seq_printf(seq, "%pK %-3d %-6d %08x %-8d %-8d %pK %-8d %-8d %-8lu\n",
+			   s,
+			   s->sk_protocol,
+			   nlk->pid,
+			   nlk->groups ? (u32)nlk->groups[0] : 0,
+			   sk_rmem_alloc_get(s),
+			   sk_wmem_alloc_get(s),
+			   nlk->cb,
+			   atomic_read(&s->sk_refcnt),
+			   atomic_read(&s->sk_drops),
+			   sock_i_ino(s)
+			);
+
+	}
+	return 0;
+}
+
+static const struct seq_operations netlink_seq_ops = {
+	.start  = netlink_seq_start,
+	.next   = netlink_seq_next,
+	.stop   = netlink_seq_stop,
+	.show   = netlink_seq_show,
+};
+
+
+static int netlink_seq_open(struct inode *inode, struct file *file)
+{
+	return seq_open_net(inode, file, &netlink_seq_ops,
+				sizeof(struct nl_seq_iter));
+}
+
+static const struct file_operations netlink_seq_fops = {
+	.owner		= THIS_MODULE,
+	.open		= netlink_seq_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release_net,
+};
+
+#endif
+
+int netlink_register_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(&netlink_chain, nb);
+}
+EXPORT_SYMBOL(netlink_register_notifier);
+
+int netlink_unregister_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_unregister(&netlink_chain, nb);
+}
+EXPORT_SYMBOL(netlink_unregister_notifier);
+
+static const struct proto_ops netlink_ops = {
+	.family =	PF_NETLINK,
+	.owner =	THIS_MODULE,
+	.release =	netlink_release,
+	.bind =		netlink_bind,
+	.connect =	netlink_connect,
+	.socketpair =	sock_no_socketpair,
+	.accept =	sock_no_accept,
+	.getname =	netlink_getname,
+	.poll =		datagram_poll,
+	.ioctl =	sock_no_ioctl,
+	.listen =	sock_no_listen,
+	.shutdown =	sock_no_shutdown,
+	.setsockopt =	netlink_setsockopt,
+	.getsockopt =	netlink_getsockopt,
+	.sendmsg =	netlink_sendmsg,
+	.recvmsg =	netlink_recvmsg,
+	.mmap =		sock_no_mmap,
+	.sendpage =	sock_no_sendpage,
+};
+
+static const struct net_proto_family netlink_family_ops = {
+	.family = PF_NETLINK,
+	.create = netlink_create,
+	.owner	= THIS_MODULE,	/* for consistency 8) */
+};
+
+static int __net_init netlink_net_init(struct net *net)
+{
+#ifdef CONFIG_PROC_FS
+	if (!proc_net_fops_create(net, "netlink", 0, &netlink_seq_fops))
+		return -ENOMEM;
+#endif
+	return 0;
+}
+
+static void __net_exit netlink_net_exit(struct net *net)
+{
+#ifdef CONFIG_PROC_FS
+	proc_net_remove(net, "netlink");
+#endif
+}
+
+static void __init netlink_add_usersock_entry(void)
+{
+	struct listeners *listeners;
+	int groups = 32;
+
+	listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL);
+	if (!listeners)
+		panic("netlink_add_usersock_entry: Cannot allocate listeners\n");
+
+	netlink_table_grab();
+
+	nl_table[NETLINK_USERSOCK].groups = groups;
+	rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners);
+	nl_table[NETLINK_USERSOCK].module = THIS_MODULE;
+	nl_table[NETLINK_USERSOCK].registered = 1;
+	nl_table[NETLINK_USERSOCK].nl_nonroot = NL_NONROOT_SEND;
+
+	netlink_table_ungrab();
+}
+
+static struct pernet_operations __net_initdata netlink_net_ops = {
+	.init = netlink_net_init,
+	.exit = netlink_net_exit,
+};
+
+static int __init netlink_proto_init(void)
+{
+	struct sk_buff *dummy_skb;
+	int i;
+	unsigned long limit;
+	unsigned int order;
+	int err = proto_register(&netlink_proto, 0);
+
+	if (err != 0)
+		goto out;
+
+	BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > sizeof(dummy_skb->cb));
+
+	nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL);
+	if (!nl_table)
+		goto panic;
+
+	if (totalram_pages >= (128 * 1024))
+		limit = totalram_pages >> (21 - PAGE_SHIFT);
+	else
+		limit = totalram_pages >> (23 - PAGE_SHIFT);
+
+	order = get_bitmask_order(limit) - 1 + PAGE_SHIFT;
+	limit = (1UL << order) / sizeof(struct hlist_head);
+	order = get_bitmask_order(min(limit, (unsigned long)UINT_MAX)) - 1;
+
+	for (i = 0; i < MAX_LINKS; i++) {
+		struct nl_pid_hash *hash = &nl_table[i].hash;
+
+		hash->table = nl_pid_hash_zalloc(1 * sizeof(*hash->table));
+		if (!hash->table) {
+			while (i-- > 0)
+				nl_pid_hash_free(nl_table[i].hash.table,
+						 1 * sizeof(*hash->table));
+			kfree(nl_table);
+			goto panic;
+		}
+		hash->max_shift = order;
+		hash->shift = 0;
+		hash->mask = 0;
+		hash->rehash_time = jiffies;
+	}
+
+	netlink_add_usersock_entry();
+
+	sock_register(&netlink_family_ops);
+	register_pernet_subsys(&netlink_net_ops);
+	/* The netlink device handler may be needed early. */
+	rtnetlink_init();
+out:
+	return err;
+panic:
+	panic("netlink_init: Cannot allocate nl_table\n");
+}
+
+core_initcall(netlink_proto_init);
diff --git a/ap/os/linux/linux-3.4.x/net/netlink/genetlink.c b/ap/os/linux/linux-3.4.x/net/netlink/genetlink.c
new file mode 100644
index 0000000..73d3f0c
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/net/netlink/genetlink.c
@@ -0,0 +1,1015 @@
+/*
+ * NETLINK      Generic Netlink Family
+ *
+ * 		Authors:	Jamal Hadi Salim
+ * 				Thomas Graf <tgraf@suug.ch>
+ *				Johannes Berg <johannes@sipsolutions.net>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/string.h>
+#include <linux/skbuff.h>
+#include <linux/mutex.h>
+#include <linux/bitmap.h>
+#include <net/sock.h>
+#include <net/genetlink.h>
+
+static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */
+
+void genl_lock(void)
+{
+	mutex_lock(&genl_mutex);
+}
+EXPORT_SYMBOL(genl_lock);
+
+void genl_unlock(void)
+{
+	mutex_unlock(&genl_mutex);
+}
+EXPORT_SYMBOL(genl_unlock);
+
+#ifdef CONFIG_PROVE_LOCKING
+int lockdep_genl_is_held(void)
+{
+	return lockdep_is_held(&genl_mutex);
+}
+EXPORT_SYMBOL(lockdep_genl_is_held);
+#endif
+
+#define GENL_FAM_TAB_SIZE	16
+#define GENL_FAM_TAB_MASK	(GENL_FAM_TAB_SIZE - 1)
+
+static struct list_head family_ht[GENL_FAM_TAB_SIZE];
+/*
+ * Bitmap of multicast groups that are currently in use.
+ *
+ * To avoid an allocation at boot of just one unsigned long,
+ * declare it global instead.
+ * Bit 0 is marked as already used since group 0 is invalid.
+ */
+static unsigned long mc_group_start = 0x1;
+static unsigned long *mc_groups = &mc_group_start;
+static unsigned long mc_groups_longs = 1;
+
+static int genl_ctrl_event(int event, void *data);
+
+static inline unsigned int genl_family_hash(unsigned int id)
+{
+	return id & GENL_FAM_TAB_MASK;
+}
+
+static inline struct list_head *genl_family_chain(unsigned int id)
+{
+	return &family_ht[genl_family_hash(id)];
+}
+
+static struct genl_family *genl_family_find_byid(unsigned int id)
+{
+	struct genl_family *f;
+
+	list_for_each_entry(f, genl_family_chain(id), family_list)
+		if (f->id == id)
+			return f;
+
+	return NULL;
+}
+
+static struct genl_family *genl_family_find_byname(char *name)
+{
+	struct genl_family *f;
+	int i;
+
+	for (i = 0; i < GENL_FAM_TAB_SIZE; i++)
+		list_for_each_entry(f, genl_family_chain(i), family_list)
+			if (strcmp(f->name, name) == 0)
+				return f;
+
+	return NULL;
+}
+
+static struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family)
+{
+	struct genl_ops *ops;
+
+	list_for_each_entry(ops, &family->ops_list, ops_list)
+		if (ops->cmd == cmd)
+			return ops;
+
+	return NULL;
+}
+
+/* Of course we are going to have problems once we hit
+ * 2^16 alive types, but that can only happen by year 2K
+*/
+static u16 genl_generate_id(void)
+{
+	static u16 id_gen_idx = GENL_MIN_ID;
+	int i;
+
+	for (i = 0; i <= GENL_MAX_ID - GENL_MIN_ID; i++) {
+		if (!genl_family_find_byid(id_gen_idx))
+			return id_gen_idx;
+		if (++id_gen_idx > GENL_MAX_ID)
+			id_gen_idx = GENL_MIN_ID;
+	}
+
+	return 0;
+}
+
+static struct genl_multicast_group notify_grp;
+
+/**
+ * genl_register_mc_group - register a multicast group
+ *
+ * Registers the specified multicast group and notifies userspace
+ * about the new group.
+ *
+ * Returns 0 on success or a negative error code.
+ *
+ * @family: The generic netlink family the group shall be registered for.
+ * @grp: The group to register, must have a name.
+ */
+int genl_register_mc_group(struct genl_family *family,
+			   struct genl_multicast_group *grp)
+{
+	int id;
+	unsigned long *new_groups;
+	int err = 0;
+
+	BUG_ON(grp->name[0] == '\0');
+	BUG_ON(memchr(grp->name, '\0', GENL_NAMSIZ) == NULL);
+
+	genl_lock();
+
+	/* special-case our own group */
+	if (grp == &notify_grp)
+		id = GENL_ID_CTRL;
+	else
+		id = find_first_zero_bit(mc_groups,
+					 mc_groups_longs * BITS_PER_LONG);
+
+
+	if (id >= mc_groups_longs * BITS_PER_LONG) {
+		size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long);
+
+		if (mc_groups == &mc_group_start) {
+			new_groups = kzalloc(nlen, GFP_KERNEL);
+			if (!new_groups) {
+				err = -ENOMEM;
+				goto out;
+			}
+			mc_groups = new_groups;
+			*mc_groups = mc_group_start;
+		} else {
+			new_groups = krealloc(mc_groups, nlen, GFP_KERNEL);
+			if (!new_groups) {
+				err = -ENOMEM;
+				goto out;
+			}
+			mc_groups = new_groups;
+			mc_groups[mc_groups_longs] = 0;
+		}
+		mc_groups_longs++;
+	}
+
+	if (family->netnsok) {
+		struct net *net;
+
+		netlink_table_grab();
+		rcu_read_lock();
+		for_each_net_rcu(net) {
+			err = __netlink_change_ngroups(net->genl_sock,
+					mc_groups_longs * BITS_PER_LONG);
+			if (err) {
+				/*
+				 * No need to roll back, can only fail if
+				 * memory allocation fails and then the
+				 * number of _possible_ groups has been
+				 * increased on some sockets which is ok.
+				 */
+				rcu_read_unlock();
+				netlink_table_ungrab();
+				goto out;
+			}
+		}
+		rcu_read_unlock();
+		netlink_table_ungrab();
+	} else {
+		err = netlink_change_ngroups(init_net.genl_sock,
+					     mc_groups_longs * BITS_PER_LONG);
+		if (err)
+			goto out;
+	}
+
+	grp->id = id;
+	set_bit(id, mc_groups);
+	list_add_tail(&grp->list, &family->mcast_groups);
+	grp->family = family;
+
+	genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp);
+ out:
+	genl_unlock();
+	return err;
+}
+EXPORT_SYMBOL(genl_register_mc_group);
+
+static void __genl_unregister_mc_group(struct genl_family *family,
+				       struct genl_multicast_group *grp)
+{
+	struct net *net;
+	BUG_ON(grp->family != family);
+
+	netlink_table_grab();
+	rcu_read_lock();
+	for_each_net_rcu(net)
+		__netlink_clear_multicast_users(net->genl_sock, grp->id);
+	rcu_read_unlock();
+	netlink_table_ungrab();
+
+	clear_bit(grp->id, mc_groups);
+	list_del(&grp->list);
+	genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp);
+	grp->id = 0;
+	grp->family = NULL;
+}
+
+/**
+ * genl_unregister_mc_group - unregister a multicast group
+ *
+ * Unregisters the specified multicast group and notifies userspace
+ * about it. All current listeners on the group are removed.
+ *
+ * Note: It is not necessary to unregister all multicast groups before
+ *       unregistering the family, unregistering the family will cause
+ *       all assigned multicast groups to be unregistered automatically.
+ *
+ * @family: Generic netlink family the group belongs to.
+ * @grp: The group to unregister, must have been registered successfully
+ *	 previously.
+ */
+void genl_unregister_mc_group(struct genl_family *family,
+			      struct genl_multicast_group *grp)
+{
+	genl_lock();
+	__genl_unregister_mc_group(family, grp);
+	genl_unlock();
+}
+EXPORT_SYMBOL(genl_unregister_mc_group);
+
+static void genl_unregister_mc_groups(struct genl_family *family)
+{
+	struct genl_multicast_group *grp, *tmp;
+
+	list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list)
+		__genl_unregister_mc_group(family, grp);
+}
+
+/**
+ * genl_register_ops - register generic netlink operations
+ * @family: generic netlink family
+ * @ops: operations to be registered
+ *
+ * Registers the specified operations and assigns them to the specified
+ * family. Either a doit or dumpit callback must be specified or the
+ * operation will fail. Only one operation structure per command
+ * identifier may be registered.
+ *
+ * See include/net/genetlink.h for more documenation on the operations
+ * structure.
+ *
+ * Returns 0 on success or a negative error code.
+ */
+int genl_register_ops(struct genl_family *family, struct genl_ops *ops)
+{
+	int err = -EINVAL;
+
+	if (ops->dumpit == NULL && ops->doit == NULL)
+		goto errout;
+
+	if (genl_get_cmd(ops->cmd, family)) {
+		err = -EEXIST;
+		goto errout;
+	}
+
+	if (ops->dumpit)
+		ops->flags |= GENL_CMD_CAP_DUMP;
+	if (ops->doit)
+		ops->flags |= GENL_CMD_CAP_DO;
+	if (ops->policy)
+		ops->flags |= GENL_CMD_CAP_HASPOL;
+
+	genl_lock();
+	list_add_tail(&ops->ops_list, &family->ops_list);
+	genl_unlock();
+
+	genl_ctrl_event(CTRL_CMD_NEWOPS, ops);
+	err = 0;
+errout:
+	return err;
+}
+EXPORT_SYMBOL(genl_register_ops);
+
+/**
+ * genl_unregister_ops - unregister generic netlink operations
+ * @family: generic netlink family
+ * @ops: operations to be unregistered
+ *
+ * Unregisters the specified operations and unassigns them from the
+ * specified family. The operation blocks until the current message
+ * processing has finished and doesn't start again until the
+ * unregister process has finished.
+ *
+ * Note: It is not necessary to unregister all operations before
+ *       unregistering the family, unregistering the family will cause
+ *       all assigned operations to be unregistered automatically.
+ *
+ * Returns 0 on success or a negative error code.
+ */
+int genl_unregister_ops(struct genl_family *family, struct genl_ops *ops)
+{
+	struct genl_ops *rc;
+
+	genl_lock();
+	list_for_each_entry(rc, &family->ops_list, ops_list) {
+		if (rc == ops) {
+			list_del(&ops->ops_list);
+			genl_unlock();
+			genl_ctrl_event(CTRL_CMD_DELOPS, ops);
+			return 0;
+		}
+	}
+	genl_unlock();
+
+	return -ENOENT;
+}
+EXPORT_SYMBOL(genl_unregister_ops);
+
+/**
+ * genl_register_family - register a generic netlink family
+ * @family: generic netlink family
+ *
+ * Registers the specified family after validating it first. Only one
+ * family may be registered with the same family name or identifier.
+ * The family id may equal GENL_ID_GENERATE causing an unique id to
+ * be automatically generated and assigned.
+ *
+ * Return 0 on success or a negative error code.
+ */
+int genl_register_family(struct genl_family *family)
+{
+	int err = -EINVAL;
+
+	if (family->id && family->id < GENL_MIN_ID)
+		goto errout;
+
+	if (family->id > GENL_MAX_ID)
+		goto errout;
+
+	INIT_LIST_HEAD(&family->ops_list);
+	INIT_LIST_HEAD(&family->mcast_groups);
+
+	genl_lock();
+
+	if (genl_family_find_byname(family->name)) {
+		err = -EEXIST;
+		goto errout_locked;
+	}
+
+	if (family->id == GENL_ID_GENERATE) {
+		u16 newid = genl_generate_id();
+
+		if (!newid) {
+			err = -ENOMEM;
+			goto errout_locked;
+		}
+
+		family->id = newid;
+	} else if (genl_family_find_byid(family->id)) {
+		err = -EEXIST;
+		goto errout_locked;
+	}
+
+	if (family->maxattr) {
+		family->attrbuf = kmalloc((family->maxattr+1) *
+					sizeof(struct nlattr *), GFP_KERNEL);
+		if (family->attrbuf == NULL) {
+			err = -ENOMEM;
+			goto errout_locked;
+		}
+	} else
+		family->attrbuf = NULL;
+
+	list_add_tail(&family->family_list, genl_family_chain(family->id));
+	genl_unlock();
+
+	genl_ctrl_event(CTRL_CMD_NEWFAMILY, family);
+
+	return 0;
+
+errout_locked:
+	genl_unlock();
+errout:
+	return err;
+}
+EXPORT_SYMBOL(genl_register_family);
+
+/**
+ * genl_register_family_with_ops - register a generic netlink family
+ * @family: generic netlink family
+ * @ops: operations to be registered
+ * @n_ops: number of elements to register
+ *
+ * Registers the specified family and operations from the specified table.
+ * Only one family may be registered with the same family name or identifier.
+ *
+ * The family id may equal GENL_ID_GENERATE causing an unique id to
+ * be automatically generated and assigned.
+ *
+ * Either a doit or dumpit callback must be specified for every registered
+ * operation or the function will fail. Only one operation structure per
+ * command identifier may be registered.
+ *
+ * See include/net/genetlink.h for more documenation on the operations
+ * structure.
+ *
+ * This is equivalent to calling genl_register_family() followed by
+ * genl_register_ops() for every operation entry in the table taking
+ * care to unregister the family on error path.
+ *
+ * Return 0 on success or a negative error code.
+ */
+int genl_register_family_with_ops(struct genl_family *family,
+	struct genl_ops *ops, size_t n_ops)
+{
+	int err, i;
+
+	err = genl_register_family(family);
+	if (err)
+		return err;
+
+	for (i = 0; i < n_ops; ++i, ++ops) {
+		err = genl_register_ops(family, ops);
+		if (err)
+			goto err_out;
+	}
+	return 0;
+err_out:
+	genl_unregister_family(family);
+	return err;
+}
+EXPORT_SYMBOL(genl_register_family_with_ops);
+
+/**
+ * genl_unregister_family - unregister generic netlink family
+ * @family: generic netlink family
+ *
+ * Unregisters the specified family.
+ *
+ * Returns 0 on success or a negative error code.
+ */
+int genl_unregister_family(struct genl_family *family)
+{
+	struct genl_family *rc;
+
+	genl_lock();
+
+	genl_unregister_mc_groups(family);
+
+	list_for_each_entry(rc, genl_family_chain(family->id), family_list) {
+		if (family->id != rc->id || strcmp(rc->name, family->name))
+			continue;
+
+		list_del(&rc->family_list);
+		INIT_LIST_HEAD(&family->ops_list);
+		genl_unlock();
+
+		kfree(family->attrbuf);
+		genl_ctrl_event(CTRL_CMD_DELFAMILY, family);
+		return 0;
+	}
+
+	genl_unlock();
+
+	return -ENOENT;
+}
+EXPORT_SYMBOL(genl_unregister_family);
+
+/**
+ * genlmsg_put - Add generic netlink header to netlink message
+ * @skb: socket buffer holding the message
+ * @pid: netlink pid the message is addressed to
+ * @seq: sequence number (usually the one of the sender)
+ * @family: generic netlink family
+ * @flags netlink message flags
+ * @cmd: generic netlink command
+ *
+ * Returns pointer to user specific header
+ */
+void *genlmsg_put(struct sk_buff *skb, u32 pid, u32 seq,
+				struct genl_family *family, int flags, u8 cmd)
+{
+	struct nlmsghdr *nlh;
+	struct genlmsghdr *hdr;
+
+	nlh = nlmsg_put(skb, pid, seq, family->id, GENL_HDRLEN +
+			family->hdrsize, flags);
+	if (nlh == NULL)
+		return NULL;
+
+	hdr = nlmsg_data(nlh);
+	hdr->cmd = cmd;
+	hdr->version = family->version;
+	hdr->reserved = 0;
+
+	return (char *) hdr + GENL_HDRLEN;
+}
+EXPORT_SYMBOL(genlmsg_put);
+
+static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+	struct genl_ops *ops;
+	struct genl_family *family;
+	struct net *net = sock_net(skb->sk);
+	struct genl_info info;
+	struct genlmsghdr *hdr = nlmsg_data(nlh);
+	int hdrlen, err;
+
+	family = genl_family_find_byid(nlh->nlmsg_type);
+	if (family == NULL)
+		return -ENOENT;
+
+	/* this family doesn't exist in this netns */
+	if (!family->netnsok && !net_eq(net, &init_net))
+		return -ENOENT;
+
+	hdrlen = GENL_HDRLEN + family->hdrsize;
+	if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
+		return -EINVAL;
+
+	ops = genl_get_cmd(hdr->cmd, family);
+	if (ops == NULL)
+		return -EOPNOTSUPP;
+
+	if ((ops->flags & GENL_ADMIN_PERM) &&
+	    !capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (nlh->nlmsg_flags & NLM_F_DUMP) {
+		if (ops->dumpit == NULL)
+			return -EOPNOTSUPP;
+
+		genl_unlock();
+		{
+			struct netlink_dump_control c = {
+				.dump = ops->dumpit,
+				.done = ops->done,
+			};
+			err = netlink_dump_start(net->genl_sock, skb, nlh, &c);
+		}
+		genl_lock();
+		return err;
+	}
+
+	if (ops->doit == NULL)
+		return -EOPNOTSUPP;
+
+	if (family->attrbuf) {
+		err = nlmsg_parse(nlh, hdrlen, family->attrbuf, family->maxattr,
+				  ops->policy);
+		if (err < 0)
+			return err;
+	}
+
+	info.snd_seq = nlh->nlmsg_seq;
+	info.snd_pid = NETLINK_CB(skb).pid;
+	info.nlhdr = nlh;
+	info.genlhdr = nlmsg_data(nlh);
+	info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN;
+	info.attrs = family->attrbuf;
+	genl_info_net_set(&info, net);
+	memset(&info.user_ptr, 0, sizeof(info.user_ptr));
+
+	if (family->pre_doit) {
+		err = family->pre_doit(ops, skb, &info);
+		if (err)
+			return err;
+	}
+
+	err = ops->doit(skb, &info);
+
+	if (family->post_doit)
+		family->post_doit(ops, skb, &info);
+
+	return err;
+}
+
+static void genl_rcv(struct sk_buff *skb)
+{
+	genl_lock();
+	netlink_rcv_skb(skb, &genl_rcv_msg);
+	genl_unlock();
+}
+
+/**************************************************************************
+ * Controller
+ **************************************************************************/
+
+static struct genl_family genl_ctrl = {
+	.id = GENL_ID_CTRL,
+	.name = "nlctrl",
+	.version = 0x2,
+	.maxattr = CTRL_ATTR_MAX,
+	.netnsok = true,
+};
+
+static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq,
+			  u32 flags, struct sk_buff *skb, u8 cmd)
+{
+	void *hdr;
+
+	hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd);
+	if (hdr == NULL)
+		return -1;
+
+	NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, family->name);
+	NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, family->id);
+	NLA_PUT_U32(skb, CTRL_ATTR_VERSION, family->version);
+	NLA_PUT_U32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize);
+	NLA_PUT_U32(skb, CTRL_ATTR_MAXATTR, family->maxattr);
+
+	if (!list_empty(&family->ops_list)) {
+		struct nlattr *nla_ops;
+		struct genl_ops *ops;
+		int idx = 1;
+
+		nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS);
+		if (nla_ops == NULL)
+			goto nla_put_failure;
+
+		list_for_each_entry(ops, &family->ops_list, ops_list) {
+			struct nlattr *nest;
+
+			nest = nla_nest_start(skb, idx++);
+			if (nest == NULL)
+				goto nla_put_failure;
+
+			NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd);
+			NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags);
+
+			nla_nest_end(skb, nest);
+		}
+
+		nla_nest_end(skb, nla_ops);
+	}
+
+	if (!list_empty(&family->mcast_groups)) {
+		struct genl_multicast_group *grp;
+		struct nlattr *nla_grps;
+		int idx = 1;
+
+		nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS);
+		if (nla_grps == NULL)
+			goto nla_put_failure;
+
+		list_for_each_entry(grp, &family->mcast_groups, list) {
+			struct nlattr *nest;
+
+			nest = nla_nest_start(skb, idx++);
+			if (nest == NULL)
+				goto nla_put_failure;
+
+			NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id);
+			NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME,
+				       grp->name);
+
+			nla_nest_end(skb, nest);
+		}
+		nla_nest_end(skb, nla_grps);
+	}
+
+	return genlmsg_end(skb, hdr);
+
+nla_put_failure:
+	genlmsg_cancel(skb, hdr);
+	return -EMSGSIZE;
+}
+
+static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 pid,
+				u32 seq, u32 flags, struct sk_buff *skb,
+				u8 cmd)
+{
+	void *hdr;
+	struct nlattr *nla_grps;
+	struct nlattr *nest;
+
+	hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd);
+	if (hdr == NULL)
+		return -1;
+
+	NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name);
+	NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id);
+
+	nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS);
+	if (nla_grps == NULL)
+		goto nla_put_failure;
+
+	nest = nla_nest_start(skb, 1);
+	if (nest == NULL)
+		goto nla_put_failure;
+
+	NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id);
+	NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME,
+		       grp->name);
+
+	nla_nest_end(skb, nest);
+	nla_nest_end(skb, nla_grps);
+
+	return genlmsg_end(skb, hdr);
+
+nla_put_failure:
+	genlmsg_cancel(skb, hdr);
+	return -EMSGSIZE;
+}
+
+static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb)
+{
+
+	int i, n = 0;
+	struct genl_family *rt;
+	struct net *net = sock_net(skb->sk);
+	int chains_to_skip = cb->args[0];
+	int fams_to_skip = cb->args[1];
+
+	for (i = chains_to_skip; i < GENL_FAM_TAB_SIZE; i++) {
+		n = 0;
+		list_for_each_entry(rt, genl_family_chain(i), family_list) {
+			if (!rt->netnsok && !net_eq(net, &init_net))
+				continue;
+			if (++n < fams_to_skip)
+				continue;
+			if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).pid,
+					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
+					   skb, CTRL_CMD_NEWFAMILY) < 0)
+				goto errout;
+		}
+
+		fams_to_skip = 0;
+	}
+
+errout:
+	cb->args[0] = i;
+	cb->args[1] = n;
+
+	return skb->len;
+}
+
+static struct sk_buff *ctrl_build_family_msg(struct genl_family *family,
+					     u32 pid, int seq, u8 cmd)
+{
+	struct sk_buff *skb;
+	int err;
+
+	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (skb == NULL)
+		return ERR_PTR(-ENOBUFS);
+
+	err = ctrl_fill_info(family, pid, seq, 0, skb, cmd);
+	if (err < 0) {
+		nlmsg_free(skb);
+		return ERR_PTR(err);
+	}
+
+	return skb;
+}
+
+static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp,
+					    u32 pid, int seq, u8 cmd)
+{
+	struct sk_buff *skb;
+	int err;
+
+	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (skb == NULL)
+		return ERR_PTR(-ENOBUFS);
+
+	err = ctrl_fill_mcgrp_info(grp, pid, seq, 0, skb, cmd);
+	if (err < 0) {
+		nlmsg_free(skb);
+		return ERR_PTR(err);
+	}
+
+	return skb;
+}
+
+static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = {
+	[CTRL_ATTR_FAMILY_ID]	= { .type = NLA_U16 },
+	[CTRL_ATTR_FAMILY_NAME]	= { .type = NLA_NUL_STRING,
+				    .len = GENL_NAMSIZ - 1 },
+};
+
+static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info)
+{
+	struct sk_buff *msg;
+	struct genl_family *res = NULL;
+	int err = -EINVAL;
+
+	if (info->attrs[CTRL_ATTR_FAMILY_ID]) {
+		u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]);
+		res = genl_family_find_byid(id);
+		err = -ENOENT;
+	}
+
+	if (info->attrs[CTRL_ATTR_FAMILY_NAME]) {
+		char *name;
+
+		name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]);
+		res = genl_family_find_byname(name);
+#ifdef CONFIG_MODULES
+		if (res == NULL) {
+			genl_unlock();
+			request_module("net-pf-%d-proto-%d-type-%s",
+				       PF_NETLINK, NETLINK_GENERIC, name);
+			genl_lock();
+			res = genl_family_find_byname(name);
+		}
+#endif
+		err = -ENOENT;
+	}
+
+	if (res == NULL)
+		return err;
+
+	if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) {
+		/* family doesn't exist here */
+		return -ENOENT;
+	}
+
+	msg = ctrl_build_family_msg(res, info->snd_pid, info->snd_seq,
+				    CTRL_CMD_NEWFAMILY);
+	if (IS_ERR(msg))
+		return PTR_ERR(msg);
+
+	return genlmsg_reply(msg, info);
+}
+
+static int genl_ctrl_event(int event, void *data)
+{
+	struct sk_buff *msg;
+	struct genl_family *family;
+	struct genl_multicast_group *grp;
+
+	/* genl is still initialising */
+	if (!init_net.genl_sock)
+		return 0;
+
+	switch (event) {
+	case CTRL_CMD_NEWFAMILY:
+	case CTRL_CMD_DELFAMILY:
+		family = data;
+		msg = ctrl_build_family_msg(family, 0, 0, event);
+		break;
+	case CTRL_CMD_NEWMCAST_GRP:
+	case CTRL_CMD_DELMCAST_GRP:
+		grp = data;
+		family = grp->family;
+		msg = ctrl_build_mcgrp_msg(data, 0, 0, event);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (IS_ERR(msg))
+		return PTR_ERR(msg);
+
+	if (!family->netnsok) {
+		genlmsg_multicast_netns(&init_net, msg, 0,
+					GENL_ID_CTRL, GFP_KERNEL);
+	} else {
+		rcu_read_lock();
+		genlmsg_multicast_allns(msg, 0, GENL_ID_CTRL, GFP_ATOMIC);
+		rcu_read_unlock();
+	}
+
+	return 0;
+}
+
+static struct genl_ops genl_ctrl_ops = {
+	.cmd		= CTRL_CMD_GETFAMILY,
+	.doit		= ctrl_getfamily,
+	.dumpit		= ctrl_dumpfamily,
+	.policy		= ctrl_policy,
+};
+
+static struct genl_multicast_group notify_grp = {
+	.name		= "notify",
+};
+
+static int __net_init genl_pernet_init(struct net *net)
+{
+	/* we'll bump the group number right afterwards */
+	net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, 0,
+					       genl_rcv, &genl_mutex,
+					       THIS_MODULE);
+
+	if (!net->genl_sock && net_eq(net, &init_net))
+		panic("GENL: Cannot initialize generic netlink\n");
+
+	if (!net->genl_sock)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void __net_exit genl_pernet_exit(struct net *net)
+{
+	netlink_kernel_release(net->genl_sock);
+	net->genl_sock = NULL;
+}
+
+static struct pernet_operations genl_pernet_ops = {
+	.init = genl_pernet_init,
+	.exit = genl_pernet_exit,
+};
+
+static int __init genl_init(void)
+{
+	int i, err;
+
+	for (i = 0; i < GENL_FAM_TAB_SIZE; i++)
+		INIT_LIST_HEAD(&family_ht[i]);
+
+	err = genl_register_family_with_ops(&genl_ctrl, &genl_ctrl_ops, 1);
+	if (err < 0)
+		goto problem;
+
+	netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV);
+
+	err = register_pernet_subsys(&genl_pernet_ops);
+	if (err)
+		goto problem;
+
+	err = genl_register_mc_group(&genl_ctrl, &notify_grp);
+	if (err < 0)
+		goto problem;
+
+	return 0;
+
+problem:
+	panic("GENL: Cannot register controller: %d\n", err);
+}
+
+subsys_initcall(genl_init);
+
+static int genlmsg_mcast(struct sk_buff *skb, u32 pid, unsigned long group,
+			 gfp_t flags)
+{
+	struct sk_buff *tmp;
+	struct net *net, *prev = NULL;
+	int err;
+
+	for_each_net_rcu(net) {
+		if (prev) {
+			tmp = skb_clone(skb, flags);
+			if (!tmp) {
+				err = -ENOMEM;
+				goto error;
+			}
+			err = nlmsg_multicast(prev->genl_sock, tmp,
+					      pid, group, flags);
+			if (err)
+				goto error;
+		}
+
+		prev = net;
+	}
+
+	return nlmsg_multicast(prev->genl_sock, skb, pid, group, flags);
+ error:
+	kfree_skb(skb);
+	return err;
+}
+
+int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid, unsigned int group,
+			    gfp_t flags)
+{
+	return genlmsg_mcast(skb, pid, group, flags);
+}
+EXPORT_SYMBOL(genlmsg_multicast_allns);
+
+void genl_notify(struct sk_buff *skb, struct net *net, u32 pid, u32 group,
+		 struct nlmsghdr *nlh, gfp_t flags)
+{
+	struct sock *sk = net->genl_sock;
+	int report = 0;
+
+	if (nlh)
+		report = nlmsg_report(nlh);
+
+	nlmsg_notify(sk, skb, pid, group, report, flags);
+}
+EXPORT_SYMBOL(genl_notify);