Commit 9368a53c authored by Gao feng's avatar Gao feng Committed by Pablo Neira Ayuso
Browse files

netfilter: nfnetlink_log: add net namespace support for nfnetlink_log 



This patch makes /proc/net/netfilter/nfnetlink_log pernet.
Moreover, there's a pernet instance table and lock.

Signed-off-by: default avatarGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 35543067

net/netfilter/nfnetlink_log.c

+117 −60
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
#include <linux/slab.h>

#include <net/sock.h>

#include <net/netfilter/nf_log.h>

#include <net/netns/generic.h>

#include <net/netfilter/nfnetlink_log.h>



#include <linux/atomic.h>
@@ -56,6 +57,7 @@ struct nfulnl_instance { 
	unsigned int qlen;		/* number of nlmsgs in skb */

	struct sk_buff *skb;		/* pre-allocatd skb */

	struct timer_list timer;

	struct net *net;

	struct user_namespace *peer_user_ns;	/* User namespace of the peer process */

	int peer_portid;			/* PORTID of the peer process */
@@ -71,25 +73,34 @@ struct nfulnl_instance { 
	struct rcu_head rcu;

};



static DEFINE_SPINLOCK(instances_lock);

static atomic_t global_seq;



#define INSTANCE_BUCKETS	16

static struct hlist_head instance_table[INSTANCE_BUCKETS];

static unsigned int hash_init;



static int nfnl_log_net_id __read_mostly;



struct nfnl_log_net {

	spinlock_t instances_lock;

	struct hlist_head instance_table[INSTANCE_BUCKETS];

	atomic_t global_seq;

};



static struct nfnl_log_net *nfnl_log_pernet(struct net *net)

{

	return net_generic(net, nfnl_log_net_id);

}



static inline u_int8_t instance_hashfn(u_int16_t group_num)

{

	return ((group_num & 0xff) % INSTANCE_BUCKETS);

}



static struct nfulnl_instance *

__instance_lookup(u_int16_t group_num)

__instance_lookup(struct nfnl_log_net *log, u_int16_t group_num)

{

	struct hlist_head *head;

	struct nfulnl_instance *inst;



	head = &instance_table[instance_hashfn(group_num)];

	head = &log->instance_table[instance_hashfn(group_num)];

	hlist_for_each_entry_rcu(inst, head, hlist) {

		if (inst->group_num == group_num)

			return inst;
@@ -104,12 +115,12 @@ instance_get(struct nfulnl_instance *inst) 
}



static struct nfulnl_instance *

instance_lookup_get(u_int16_t group_num)

instance_lookup_get(struct nfnl_log_net *log, u_int16_t group_num)

{

	struct nfulnl_instance *inst;



	rcu_read_lock_bh();

	inst = __instance_lookup(group_num);

	inst = __instance_lookup(log, group_num);

	if (inst && !atomic_inc_not_zero(&inst->use))

		inst = NULL;

	rcu_read_unlock_bh();
@@ -119,7 +130,11 @@ instance_lookup_get(u_int16_t group_num) 


static void nfulnl_instance_free_rcu(struct rcu_head *head)

{

	kfree(container_of(head, struct nfulnl_instance, rcu));

	struct nfulnl_instance *inst =

		container_of(head, struct nfulnl_instance, rcu);



	put_net(inst->net);

	kfree(inst);

	module_put(THIS_MODULE);

}
@@ -133,13 +148,15 @@ instance_put(struct nfulnl_instance *inst) 
static void nfulnl_timer(unsigned long data);



static struct nfulnl_instance *

instance_create(u_int16_t group_num, int portid, struct user_namespace *user_ns)

instance_create(struct net *net, u_int16_t group_num,

		int portid, struct user_namespace *user_ns)

{

	struct nfulnl_instance *inst;

	struct nfnl_log_net *log = nfnl_log_pernet(net);

	int err;



	spin_lock_bh(&instances_lock);

	if (__instance_lookup(group_num)) {

	spin_lock_bh(&log->instances_lock);

	if (__instance_lookup(log, group_num)) {

		err = -EEXIST;

		goto out_unlock;

	}
@@ -163,6 +180,7 @@ instance_create(u_int16_t group_num, int portid, struct user_namespace *user_ns) 


	setup_timer(&inst->timer, nfulnl_timer, (unsigned long)inst);



	inst->net = get_net(net);

	inst->peer_user_ns = user_ns;

	inst->peer_portid = portid;

	inst->group_num = group_num;
@@ -174,14 +192,15 @@ instance_create(u_int16_t group_num, int portid, struct user_namespace *user_ns) 
	inst->copy_range 	= NFULNL_COPY_RANGE_MAX;



	hlist_add_head_rcu(&inst->hlist,

		       &instance_table[instance_hashfn(group_num)]);

		       &log->instance_table[instance_hashfn(group_num)]);





	spin_unlock_bh(&instances_lock);

	spin_unlock_bh(&log->instances_lock);



	return inst;



out_unlock:

	spin_unlock_bh(&instances_lock);

	spin_unlock_bh(&log->instances_lock);

	return ERR_PTR(err);

}
@@ -210,11 +229,12 @@ __instance_destroy(struct nfulnl_instance *inst) 
}



static inline void

instance_destroy(struct nfulnl_instance *inst)

instance_destroy(struct nfnl_log_net *log,

		 struct nfulnl_instance *inst)

{

	spin_lock_bh(&instances_lock);

	spin_lock_bh(&log->instances_lock);

	__instance_destroy(inst);

	spin_unlock_bh(&instances_lock);

	spin_unlock_bh(&log->instances_lock);

}



static int
@@ -336,7 +356,7 @@ __nfulnl_send(struct nfulnl_instance *inst) 
		if (!nlh)

			goto out;

	}

	status = nfnetlink_unicast(inst->skb, &init_net, inst->peer_portid,

	status = nfnetlink_unicast(inst->skb, inst->net, inst->peer_portid,

				   MSG_DONTWAIT);



	inst->qlen = 0;
@@ -370,7 +390,8 @@ nfulnl_timer(unsigned long data) 
/* This is an inline function, we don't really care about a long

 * list of arguments */

static inline int

__build_packet_message(struct nfulnl_instance *inst,

__build_packet_message(struct nfnl_log_net *log,

			struct nfulnl_instance *inst,

			const struct sk_buff *skb,

			unsigned int data_len,

			u_int8_t pf,
@@ -536,7 +557,7 @@ __build_packet_message(struct nfulnl_instance *inst, 
	/* global sequence number */

	if ((inst->flags & NFULNL_CFG_F_SEQ_GLOBAL) &&

	    nla_put_be32(inst->skb, NFULA_SEQ_GLOBAL,

			 htonl(atomic_inc_return(&global_seq))))

			 htonl(atomic_inc_return(&log->global_seq))))

		goto nla_put_failure;



	if (data_len) {
@@ -592,13 +613,15 @@ nfulnl_log_packet(u_int8_t pf, 
	const struct nf_loginfo *li;

	unsigned int qthreshold;

	unsigned int plen;

	struct net *net = dev_net(in ? in : out);

	struct nfnl_log_net *log = nfnl_log_pernet(net);



	if (li_user && li_user->type == NF_LOG_TYPE_ULOG)

		li = li_user;

	else

		li = &default_loginfo;



	inst = instance_lookup_get(li->u.ulog.group);

	inst = instance_lookup_get(log, li->u.ulog.group);

	if (!inst)

		return;
@@ -680,7 +703,7 @@ nfulnl_log_packet(u_int8_t pf, 


	inst->qlen++;



	__build_packet_message(inst, skb, data_len, pf,

	__build_packet_message(log, inst, skb, data_len, pf,

				hooknum, in, out, prefix, plen);



	if (inst->qlen >= qthreshold)
@@ -709,24 +732,24 @@ nfulnl_rcv_nl_event(struct notifier_block *this, 
		   unsigned long event, void *ptr)

{

	struct netlink_notify *n = ptr;

	struct nfnl_log_net *log = nfnl_log_pernet(n->net);



	if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {

		int i;



		/* destroy all instances for this portid */

		spin_lock_bh(&instances_lock);

		spin_lock_bh(&log->instances_lock);

		for  (i = 0; i < INSTANCE_BUCKETS; i++) {

			struct hlist_node *t2;

			struct nfulnl_instance *inst;

			struct hlist_head *head = &instance_table[i];

			struct hlist_head *head = &log->instance_table[i];



			hlist_for_each_entry_safe(inst, t2, head, hlist) {

				if ((net_eq(n->net, &init_net)) &&

				    (n->portid == inst->peer_portid))

				if (n->portid == inst->peer_portid)

					__instance_destroy(inst);

			}

		}

		spin_unlock_bh(&instances_lock);

		spin_unlock_bh(&log->instances_lock);

	}

	return NOTIFY_DONE;

}
@@ -768,6 +791,7 @@ nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb, 
	struct nfulnl_instance *inst;

	struct nfulnl_msg_config_cmd *cmd = NULL;

	struct net *net = sock_net(ctnl);

	struct nfnl_log_net *log = nfnl_log_pernet(net);

	int ret = 0;



	if (nfula[NFULA_CFG_CMD]) {
@@ -784,7 +808,7 @@ nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb, 
		}

	}



	inst = instance_lookup_get(group_num);

	inst = instance_lookup_get(log, group_num);

	if (inst && inst->peer_portid != NETLINK_CB(skb).portid) {

		ret = -EPERM;

		goto out_put;
@@ -798,7 +822,7 @@ nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb, 
				goto out_put;

			}



			inst = instance_create(group_num,

			inst = instance_create(net, group_num,

					       NETLINK_CB(skb).portid,

					       sk_user_ns(NETLINK_CB(skb).ssk));

			if (IS_ERR(inst)) {
@@ -812,7 +836,7 @@ nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb, 
				goto out;

			}



			instance_destroy(inst);

			instance_destroy(log, inst);

			goto out_put;

		default:

			ret = -ENOTSUPP;
@@ -895,55 +919,68 @@ static const struct nfnetlink_subsystem nfulnl_subsys = { 


#ifdef CONFIG_PROC_FS

struct iter_state {

	struct seq_net_private p;

	unsigned int bucket;

};



static struct hlist_node *get_first(struct iter_state *st)

static struct hlist_node *get_first(struct net *net, struct iter_state *st)

{

	struct nfnl_log_net *log;

	if (!st)

		return NULL;



	log = nfnl_log_pernet(net);



	for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {

		if (!hlist_empty(&instance_table[st->bucket]))

			return rcu_dereference_bh(hlist_first_rcu(&instance_table[st->bucket]));

		struct hlist_head *head = &log->instance_table[st->bucket];



		if (!hlist_empty(head))

			return rcu_dereference_bh(hlist_first_rcu(head));

	}

	return NULL;

}



static struct hlist_node *get_next(struct iter_state *st, struct hlist_node *h)

static struct hlist_node *get_next(struct net *net, struct iter_state *st,

				   struct hlist_node *h)

{

	h = rcu_dereference_bh(hlist_next_rcu(h));

	while (!h) {

		struct nfnl_log_net *log;

		struct hlist_head *head;



		if (++st->bucket >= INSTANCE_BUCKETS)

			return NULL;



		h = rcu_dereference_bh(hlist_first_rcu(&instance_table[st->bucket]));

		log = nfnl_log_pernet(net);

		head = &log->instance_table[st->bucket];

		h = rcu_dereference_bh(hlist_first_rcu(head));

	}

	return h;

}



static struct hlist_node *get_idx(struct iter_state *st, loff_t pos)

static struct hlist_node *get_idx(struct net *net, struct iter_state *st,

				  loff_t pos)

{

	struct hlist_node *head;

	head = get_first(st);

	head = get_first(net, st);



	if (head)

		while (pos && (head = get_next(st, head)))

		while (pos && (head = get_next(net, st, head)))

			pos--;

	return pos ? NULL : head;

}



static void *seq_start(struct seq_file *seq, loff_t *pos)

static void *seq_start(struct seq_file *s, loff_t *pos)

	__acquires(rcu_bh)

{

	rcu_read_lock_bh();

	return get_idx(seq->private, *pos);

	return get_idx(seq_file_net(s), s->private, *pos);

}



static void *seq_next(struct seq_file *s, void *v, loff_t *pos)

{

	(*pos)++;

	return get_next(s->private, v);

	return get_next(seq_file_net(s), s->private, v);

}



static void seq_stop(struct seq_file *s, void *v)
@@ -972,7 +1009,7 @@ static const struct seq_operations nful_seq_ops = { 


static int nful_open(struct inode *inode, struct file *file)

{

	return seq_open_private(file, &nful_seq_ops,

	return seq_open_net(inode, file, &nful_seq_ops,

			    sizeof(struct iter_state));

}
@@ -981,17 +1018,43 @@ static const struct file_operations nful_file_ops = { 
	.open	 = nful_open,

	.read	 = seq_read,

	.llseek	 = seq_lseek,

	.release = seq_release_private,

	.release = seq_release_net,

};



#endif /* PROC_FS */



static int __init nfnetlink_log_init(void)

static int __net_init nfnl_log_net_init(struct net *net)

{

	int i, status = -ENOMEM;

	unsigned int i;

	struct nfnl_log_net *log = nfnl_log_pernet(net);



	for (i = 0; i < INSTANCE_BUCKETS; i++)

		INIT_HLIST_HEAD(&instance_table[i]);

		INIT_HLIST_HEAD(&log->instance_table[i]);

	spin_lock_init(&log->instances_lock);



#ifdef CONFIG_PROC_FS

	if (!proc_create("nfnetlink_log", 0440,

			 net->nf.proc_netfilter, &nful_file_ops))

		return -ENOMEM;

#endif

	return 0;

}



static void __net_exit nfnl_log_net_exit(struct net *net)

{

	remove_proc_entry("nfnetlink_log", net->nf.proc_netfilter);

}



static struct pernet_operations nfnl_log_net_ops = {

	.init	= nfnl_log_net_init,

	.exit	= nfnl_log_net_exit,

	.id	= &nfnl_log_net_id,

	.size	= sizeof(struct nfnl_log_net),

};



static int __init nfnetlink_log_init(void)

{

	int status = -ENOMEM;



	/* it's not really all that important to have a random value, so

	 * we can do this from the init function, even if there hasn't
@@ -1001,29 +1064,25 @@ static int __init nfnetlink_log_init(void) 
	netlink_register_notifier(&nfulnl_rtnl_notifier);

	status = nfnetlink_subsys_register(&nfulnl_subsys);

	if (status < 0) {

		printk(KERN_ERR "log: failed to create netlink socket\n");

		pr_err("log: failed to create netlink socket\n");

		goto cleanup_netlink_notifier;

	}



	status = nf_log_register(NFPROTO_UNSPEC, &nfulnl_logger);

	if (status < 0) {

		printk(KERN_ERR "log: failed to register logger\n");

		pr_err("log: failed to register logger\n");

		goto cleanup_subsys;

	}



#ifdef CONFIG_PROC_FS

	if (!proc_create("nfnetlink_log", 0440,

			 proc_net_netfilter, &nful_file_ops)) {

		status = -ENOMEM;

	status = register_pernet_subsys(&nfnl_log_net_ops);

	if (status < 0) {

		pr_err("log: failed to register pernet ops\n");

		goto cleanup_logger;

	}

#endif

	return status;



#ifdef CONFIG_PROC_FS

cleanup_logger:

	nf_log_unregister(&nfulnl_logger);

#endif

cleanup_subsys:

	nfnetlink_subsys_unregister(&nfulnl_subsys);

cleanup_netlink_notifier:
@@ -1033,10 +1092,8 @@ static int __init nfnetlink_log_init(void) 


static void __exit nfnetlink_log_fini(void)

{

	unregister_pernet_subsys(&nfnl_log_net_ops);

	nf_log_unregister(&nfulnl_logger);

#ifdef CONFIG_PROC_FS

	remove_proc_entry("nfnetlink_log", proc_net_netfilter);

#endif

	nfnetlink_subsys_unregister(&nfulnl_subsys);

	netlink_unregister_notifier(&nfulnl_rtnl_notifier);

}