[mirror_ubuntu-bionic-kernel.git] / include / net / inet_hashtables.h

/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the BSD Socket
 *		interface as the means of communication with the user level.
 *
 * Authors:	Lotsa people, from code originally in tcp
 *
 *	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.
 */

#ifndef _INET_HASHTABLES_H
#define _INET_HASHTABLES_H


#include <linux/interrupt.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/socket.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/wait.h>
#include <linux/vmalloc.h>

#include <net/inet_connection_sock.h>
#include <net/inet_sock.h>
#include <net/sock.h>
#include <net/route.h>
#include <net/tcp_states.h>
#include <net/netns/hash.h>

#include <linux/atomic.h>
#include <asm/byteorder.h>

/* This is for all connections with a full identity, no wildcards.
 * The 'e' prefix stands for Establish, but we really put all sockets
 * but LISTEN ones.
 */
struct inet_ehash_bucket {
	struct hlist_nulls_head chain;
};

/* There are a few simple rules, which allow for local port reuse by
 * an application.  In essence:
 *
 *	1) Sockets bound to different interfaces may share a local port.
 *	   Failing that, goto test 2.
 *	2) If all sockets have sk->sk_reuse set, and none of them are in
 *	   TCP_LISTEN state, the port may be shared.
 *	   Failing that, goto test 3.
 *	3) If all sockets are bound to a specific inet_sk(sk)->rcv_saddr local
 *	   address, and none of them are the same, the port may be
 *	   shared.
 *	   Failing this, the port cannot be shared.
 *
 * The interesting point, is test #2.  This is what an FTP server does
 * all day.  To optimize this case we use a specific flag bit defined
 * below.  As we add sockets to a bind bucket list, we perform a
 * check of: (newsk->sk_reuse && (newsk->sk_state != TCP_LISTEN))
 * As long as all sockets added to a bind bucket pass this test,
 * the flag bit will be set.
 * The resulting situation is that tcp_v[46]_verify_bind() can just check
 * for this flag bit, if it is set and the socket trying to bind has
 * sk->sk_reuse set, we don't even have to walk the owners list at all,
 * we return that it is ok to bind this socket to the requested local port.
 *
 * Sounds like a lot of work, but it is worth it.  In a more naive
 * implementation (ie. current FreeBSD etc.) the entire list of ports
 * must be walked for each data port opened by an ftp server.  Needless
 * to say, this does not scale at all.  With a couple thousand FTP
 * users logged onto your box, isn't it nice to know that new data
 * ports are created in O(1) time?  I thought so. ;-)	-DaveM
 */
struct inet_bind_bucket {
#ifdef CONFIG_NET_NS
	struct net		*ib_net;
#endif
	unsigned short		port;
	signed char		fastreuse;
	signed char		fastreuseport;
	kuid_t			fastuid;
	int			num_owners;
	struct hlist_node	node;
	struct hlist_head	owners;
};

static inline struct net *ib_net(struct inet_bind_bucket *ib)
{
	return read_pnet(&ib->ib_net);
}

#define inet_bind_bucket_for_each(tb, head) \
	hlist_for_each_entry(tb, head, node)

struct inet_bind_hashbucket {
	spinlock_t		lock;
	struct hlist_head	chain;
};

/*
 * Sockets can be hashed in established or listening table
 * We must use different 'nulls' end-of-chain value for listening
 * hash table, or we might find a socket that was closed and
 * reallocated/inserted into established hash table
 */
#define LISTENING_NULLS_BASE (1U << 29)
struct inet_listen_hashbucket {
	spinlock_t		lock;
	struct hlist_nulls_head	head;
};

/* This is for listening sockets, thus all sockets which possess wildcards. */
#define INET_LHTABLE_SIZE	32	/* Yes, really, this is all you need. */

struct inet_hashinfo {
	/* This is for sockets with full identity only.  Sockets here will
	 * always be without wildcards and will have the following invariant:
	 *
	 *          TCP_ESTABLISHED <= sk->sk_state < TCP_CLOSE
	 *
	 */
	struct inet_ehash_bucket	*ehash;
	spinlock_t			*ehash_locks;
	unsigned int			ehash_mask;
	unsigned int			ehash_locks_mask;

	/* Ok, let's try this, I give up, we do need a local binding
	 * TCP hash as well as the others for fast bind/connect.
	 */
	struct inet_bind_hashbucket	*bhash;

	unsigned int			bhash_size;
	/* 4 bytes hole on 64 bit */

	struct kmem_cache		*bind_bucket_cachep;

	/* All the above members are written once at bootup and
	 * never written again _or_ are predominantly read-access.
	 *
	 * Now align to a new cache line as all the following members
	 * might be often dirty.
	 */
	/* All sockets in TCP_LISTEN state will be in here.  This is the only
	 * table where wildcard'd TCP sockets can exist.  Hash function here
	 * is just local port number.
	 */
	struct inet_listen_hashbucket	listening_hash[INET_LHTABLE_SIZE]
					____cacheline_aligned_in_smp;

	atomic_t			bsockets;
};

static inline struct inet_ehash_bucket *inet_ehash_bucket(
	struct inet_hashinfo *hashinfo,
	unsigned int hash)
{
	return &hashinfo->ehash[hash & hashinfo->ehash_mask];
}

static inline spinlock_t *inet_ehash_lockp(
	struct inet_hashinfo *hashinfo,
	unsigned int hash)
{
	return &hashinfo->ehash_locks[hash & hashinfo->ehash_locks_mask];
}

static inline int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
{
	unsigned int i, size = 256;
#if defined(CONFIG_PROVE_LOCKING)
	unsigned int nr_pcpus = 2;
#else
	unsigned int nr_pcpus = num_possible_cpus();
#endif
	if (nr_pcpus >= 4)
		size = 512;
	if (nr_pcpus >= 8)
		size = 1024;
	if (nr_pcpus >= 16)
		size = 2048;
	if (nr_pcpus >= 32)
		size = 4096;
	if (sizeof(spinlock_t) != 0) {
#ifdef CONFIG_NUMA
		if (size * sizeof(spinlock_t) > PAGE_SIZE)
			hashinfo->ehash_locks = vmalloc(size * sizeof(spinlock_t));
		else
#endif
		hashinfo->ehash_locks =	kmalloc(size * sizeof(spinlock_t),
						GFP_KERNEL);
		if (!hashinfo->ehash_locks)
			return ENOMEM;
		for (i = 0; i < size; i++)
			spin_lock_init(&hashinfo->ehash_locks[i]);
	}
	hashinfo->ehash_locks_mask = size - 1;
	return 0;
}

static inline void inet_ehash_locks_free(struct inet_hashinfo *hashinfo)
{
	if (hashinfo->ehash_locks) {
#ifdef CONFIG_NUMA
		unsigned int size = (hashinfo->ehash_locks_mask + 1) *
							sizeof(spinlock_t);
		if (size > PAGE_SIZE)
			vfree(hashinfo->ehash_locks);
		else
#endif
		kfree(hashinfo->ehash_locks);
		hashinfo->ehash_locks = NULL;
	}
}

struct inet_bind_bucket *
inet_bind_bucket_create(struct kmem_cache *cachep, struct net *net,
			struct inet_bind_hashbucket *head,
			const unsigned short snum);
void inet_bind_bucket_destroy(struct kmem_cache *cachep,
			      struct inet_bind_bucket *tb);

static inline int inet_bhashfn(struct net *net, const __u16 lport,
			       const int bhash_size)
{
	return (lport + net_hash_mix(net)) & (bhash_size - 1);
}

void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
		    const unsigned short snum);

/* These can have wildcards, don't try too hard. */
static inline int inet_lhashfn(struct net *net, const unsigned short num)
{
	return (num + net_hash_mix(net)) & (INET_LHTABLE_SIZE - 1);
}

static inline int inet_sk_listen_hashfn(const struct sock *sk)
{
	return inet_lhashfn(sock_net(sk), inet_sk(sk)->inet_num);
}

/* Caller must disable local BH processing. */
int __inet_inherit_port(struct sock *sk, struct sock *child);

void inet_put_port(struct sock *sk);

void inet_hashinfo_init(struct inet_hashinfo *h);

int __inet_hash_nolisten(struct sock *sk, struct inet_timewait_sock *tw);
void inet_hash(struct sock *sk);
void inet_unhash(struct sock *sk);

struct sock *__inet_lookup_listener(struct net *net,
				    struct inet_hashinfo *hashinfo,
				    const __be32 saddr, const __be16 sport,
				    const __be32 daddr,
				    const unsigned short hnum,
				    const int dif);

static inline struct sock *inet_lookup_listener(struct net *net,
		struct inet_hashinfo *hashinfo,
		__be32 saddr, __be16 sport,
		__be32 daddr, __be16 dport, int dif)
{
	return __inet_lookup_listener(net, hashinfo, saddr, sport,
				      daddr, ntohs(dport), dif);
}

/* Socket demux engine toys. */
/* What happens here is ugly; there's a pair of adjacent fields in
   struct inet_sock; __be16 dport followed by __u16 num.  We want to
   search by pair, so we combine the keys into a single 32bit value
   and compare with 32bit value read from &...->dport.  Let's at least
   make sure that it's not mixed with anything else...
   On 64bit targets we combine comparisons with pair of adjacent __be32
   fields in the same way.
*/
#ifdef __BIG_ENDIAN
#define INET_COMBINED_PORTS(__sport, __dport) \
	((__force __portpair)(((__force __u32)(__be16)(__sport) << 16) | (__u32)(__dport)))
#else /* __LITTLE_ENDIAN */
#define INET_COMBINED_PORTS(__sport, __dport) \
	((__force __portpair)(((__u32)(__dport) << 16) | (__force __u32)(__be16)(__sport)))
#endif

#if (BITS_PER_LONG == 64)
#ifdef __BIG_ENDIAN
#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
	const __addrpair __name = (__force __addrpair) ( \
				   (((__force __u64)(__be32)(__saddr)) << 32) | \
				   ((__force __u64)(__be32)(__daddr)))
#else /* __LITTLE_ENDIAN */
#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
	const __addrpair __name = (__force __addrpair) ( \
				   (((__force __u64)(__be32)(__daddr)) << 32) | \
				   ((__force __u64)(__be32)(__saddr)))
#endif /* __BIG_ENDIAN */
#define INET_MATCH(__sk, __net, __cookie, __saddr, __daddr, __ports, __dif)	\
	(((__sk)->sk_portpair == (__ports))			&&	\
	 ((__sk)->sk_addrpair == (__cookie))			&&	\
	 (!(__sk)->sk_bound_dev_if	||				\
	   ((__sk)->sk_bound_dev_if == (__dif))) 		&& 	\
	 net_eq(sock_net(__sk), (__net)))
#else /* 32-bit arch */
#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
	const int __name __deprecated __attribute__((unused))

#define INET_MATCH(__sk, __net, __cookie, __saddr, __daddr, __ports, __dif) \
	(((__sk)->sk_portpair == (__ports))		&&		\
	 ((__sk)->sk_daddr	== (__saddr))		&&		\
	 ((__sk)->sk_rcv_saddr	== (__daddr))		&&		\
	 (!(__sk)->sk_bound_dev_if	||				\
	   ((__sk)->sk_bound_dev_if == (__dif))) 	&&		\
	 net_eq(sock_net(__sk), (__net)))
#endif /* 64-bit arch */

/*
 * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so we need
 * not check it for lookups anymore, thanks Alexey. -DaveM
 *
 * Local BH must be disabled here.
 */
struct sock *__inet_lookup_established(struct net *net,
				       struct inet_hashinfo *hashinfo,
				       const __be32 saddr, const __be16 sport,
				       const __be32 daddr, const u16 hnum,
				       const int dif);

static inline struct sock *
	inet_lookup_established(struct net *net, struct inet_hashinfo *hashinfo,
				const __be32 saddr, const __be16 sport,
				const __be32 daddr, const __be16 dport,
				const int dif)
{
	return __inet_lookup_established(net, hashinfo, saddr, sport, daddr,
					 ntohs(dport), dif);
}

static inline struct sock *__inet_lookup(struct net *net,
					 struct inet_hashinfo *hashinfo,
					 const __be32 saddr, const __be16 sport,
					 const __be32 daddr, const __be16 dport,
					 const int dif)
{
	u16 hnum = ntohs(dport);
	struct sock *sk = __inet_lookup_established(net, hashinfo,
				saddr, sport, daddr, hnum, dif);

	return sk ? : __inet_lookup_listener(net, hashinfo, saddr, sport,
					     daddr, hnum, dif);
}

static inline struct sock *inet_lookup(struct net *net,
				       struct inet_hashinfo *hashinfo,
				       const __be32 saddr, const __be16 sport,
				       const __be32 daddr, const __be16 dport,
				       const int dif)
{
	struct sock *sk;

	local_bh_disable();
	sk = __inet_lookup(net, hashinfo, saddr, sport, daddr, dport, dif);
	local_bh_enable();

	return sk;
}

static inline struct sock *__inet_lookup_skb(struct inet_hashinfo *hashinfo,
					     struct sk_buff *skb,
					     const __be16 sport,
					     const __be16 dport)
{
	struct sock *sk = skb_steal_sock(skb);
	const struct iphdr *iph = ip_hdr(skb);

	if (sk)
		return sk;
	else
		return __inet_lookup(dev_net(skb_dst(skb)->dev), hashinfo,
				     iph->saddr, sport,
				     iph->daddr, dport, inet_iif(skb));
}

int __inet_hash_connect(struct inet_timewait_death_row *death_row,
			struct sock *sk, u32 port_offset,
			int (*check_established)(struct inet_timewait_death_row *,
						 struct sock *, __u16,
						 struct inet_timewait_sock **),
			int (*hash)(struct sock *sk,
				    struct inet_timewait_sock *twp));

int inet_hash_connect(struct inet_timewait_death_row *death_row,
		      struct sock *sk);
#endif /* _INET_HASHTABLES_H */
Commit	Line	Data
304a1618 ACM	1	/*
	2	* INET An implementation of the TCP/IP protocol suite for the LINUX
	3	* operating system. INET is implemented using the BSD Socket
	4	* interface as the means of communication with the user level.
	5	*
	6	* Authors: Lotsa people, from code originally in tcp
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* as published by the Free Software Foundation; either version
	11	* 2 of the License, or (at your option) any later version.
	12	*/
	13
	14	#ifndef _INET_HASHTABLES_H
	15	#define _INET_HASHTABLES_H
	16
8feaf0c0	17
2d8c4ce5	18	#include <linux/interrupt.h>
9a1f27c4	19	#include <linux/ip.h>
33b62231	20	#include <linux/ipv6.h>
77d8bf9c ACM	21	#include <linux/list.h>
77d8bf9c ACM	22	#include <linux/slab.h>
33b62231	23	#include <linux/socket.h>
77d8bf9c	24	#include <linux/spinlock.h>
304a1618	25	#include <linux/types.h>
f3f05f70	26	#include <linux/wait.h>
9e4505c4	27	#include <linux/vmalloc.h>
304a1618	28
463c84b9	29	#include <net/inet_connection_sock.h>
14c85021	30	#include <net/inet_sock.h>
2d8c4ce5	31	#include <net/sock.h>
9a1f27c4	32	#include <net/route.h>
c752f073	33	#include <net/tcp_states.h>
0b441916	34	#include <net/netns/hash.h>
2d8c4ce5	35
60063497	36	#include <linux/atomic.h>
e48c414e	37	#include <asm/byteorder.h>
f3f05f70	38
77d8bf9c	39	/* This is for all connections with a full identity, no wildcards.
05dbc7b5 ED	40	* The 'e' prefix stands for Establish, but we really put all sockets
05dbc7b5 ED	41	* but LISTEN ones.
77d8bf9c ACM	42	*/
77d8bf9c ACM	43	struct inet_ehash_bucket {
3ab5aee7	44	struct hlist_nulls_head chain;
6d255361	45	};
77d8bf9c ACM	46
	47	/* There are a few simple rules, which allow for local port reuse by
	48	* an application. In essence:
	49	*
	50	* 1) Sockets bound to different interfaces may share a local port.
	51	* Failing that, goto test 2.
	52	* 2) If all sockets have sk->sk_reuse set, and none of them are in
	53	* TCP_LISTEN state, the port may be shared.
	54	* Failing that, goto test 3.
	55	* 3) If all sockets are bound to a specific inet_sk(sk)->rcv_saddr local
	56	* address, and none of them are the same, the port may be
	57	* shared.
	58	* Failing this, the port cannot be shared.
	59	*
	60	* The interesting point, is test #2. This is what an FTP server does
	61	* all day. To optimize this case we use a specific flag bit defined
	62	* below. As we add sockets to a bind bucket list, we perform a
	63	* check of: (newsk->sk_reuse && (newsk->sk_state != TCP_LISTEN))
	64	* As long as all sockets added to a bind bucket pass this test,
	65	* the flag bit will be set.
	66	* The resulting situation is that tcp_v[46]_verify_bind() can just check
	67	* for this flag bit, if it is set and the socket trying to bind has
	68	* sk->sk_reuse set, we don't even have to walk the owners list at all,
	69	* we return that it is ok to bind this socket to the requested local port.
	70	*
	71	* Sounds like a lot of work, but it is worth it. In a more naive
	72	* implementation (ie. current FreeBSD etc.) the entire list of ports
	73	* must be walked for each data port opened by an ftp server. Needless
	74	* to say, this does not scale at all. With a couple thousand FTP
	75	* users logged onto your box, isn't it nice to know that new data
	76	* ports are created in O(1) time? I thought so. ;-) -DaveM
	77	*/
	78	struct inet_bind_bucket {
7a9546ee	79	#ifdef CONFIG_NET_NS
941b1d22	80	struct net *ib_net;
7a9546ee	81	#endif
77d8bf9c	82	unsigned short port;
da5e3630 TH	83	signed char fastreuse;
	84	signed char fastreuseport;
	85	kuid_t fastuid;
a9d8f911	86	int num_owners;
77d8bf9c ACM	87	struct hlist_node node;
	88	struct hlist_head owners;
	89	};
	90
7a9546ee ED	91	static inline struct net ib_net(struct inet_bind_bucket ib)
	92	{
	93	return read_pnet(&ib->ib_net);
	94	}
	95
b67bfe0d SL	96	#define inet_bind_bucket_for_each(tb, head) \
b67bfe0d SL	97	hlist_for_each_entry(tb, head, node)
77d8bf9c ACM	98
	99	struct inet_bind_hashbucket {
	100	spinlock_t lock;
	101	struct hlist_head chain;
	102	};
	103
c25eb3bf ED	104	/*
	105	* Sockets can be hashed in established or listening table
	106	* We must use different 'nulls' end-of-chain value for listening
	107	* hash table, or we might find a socket that was closed and
	108	* reallocated/inserted into established hash table
	109	*/
	110	#define LISTENING_NULLS_BASE (1U << 29)
5caea4ea ED	111	struct inet_listen_hashbucket {
5caea4ea ED	112	spinlock_t lock;
c25eb3bf	113	struct hlist_nulls_head head;
5caea4ea ED	114	};
5caea4ea ED	115
77d8bf9c ACM	116	/* This is for listening sockets, thus all sockets which possess wildcards. */
	117	#define INET_LHTABLE_SIZE 32 /* Yes, really, this is all you need. */
	118
	119	struct inet_hashinfo {
	120	/* This is for sockets with full identity only. Sockets here will
	121	* always be without wildcards and will have the following invariant:
	122	*
	123	* TCP_ESTABLISHED <= sk->sk_state < TCP_CLOSE
	124	*
77d8bf9c ACM	125	*/
77d8bf9c ACM	126	struct inet_ehash_bucket *ehash;
9db66bdc	127	spinlock_t *ehash_locks;
f373b53b	128	unsigned int ehash_mask;
230140cf	129	unsigned int ehash_locks_mask;
77d8bf9c ACM	130
	131	/* Ok, let's try this, I give up, we do need a local binding
	132	* TCP hash as well as the others for fast bind/connect.
	133	*/
	134	struct inet_bind_hashbucket *bhash;
	135
cfcabdcc	136	unsigned int bhash_size;
24dd1fa1	137	/* 4 bytes hole on 64 bit */
77d8bf9c	138
5caea4ea	139	struct kmem_cache *bind_bucket_cachep;
77d8bf9c ACM	140
	141	/* All the above members are written once at bootup and
	142	* never written again _or_ are predominantly read-access.
	143	*
	144	* Now align to a new cache line as all the following members
5caea4ea ED	145	* might be often dirty.
	146	*/
	147	/* All sockets in TCP_LISTEN state will be in here. This is the only
	148	* table where wildcard'd TCP sockets can exist. Hash function here
	149	* is just local port number.
77d8bf9c	150	*/
5caea4ea ED	151	struct inet_listen_hashbucket listening_hash[INET_LHTABLE_SIZE]
	152	____cacheline_aligned_in_smp;
	153
24dd1fa1	154	atomic_t bsockets;
77d8bf9c ACM	155	};
77d8bf9c ACM	156
81c3d547 ED	157	static inline struct inet_ehash_bucket *inet_ehash_bucket(
	158	struct inet_hashinfo *hashinfo,
	159	unsigned int hash)
	160	{
f373b53b	161	return &hashinfo->ehash[hash & hashinfo->ehash_mask];
304a1618 ACM	162	}
304a1618 ACM	163
9db66bdc	164	static inline spinlock_t *inet_ehash_lockp(
230140cf ED	165	struct inet_hashinfo *hashinfo,
	166	unsigned int hash)
	167	{
	168	return &hashinfo->ehash_locks[hash & hashinfo->ehash_locks_mask];
	169	}
	170
	171	static inline int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
	172	{
	173	unsigned int i, size = 256;
	174	#if defined(CONFIG_PROVE_LOCKING)
	175	unsigned int nr_pcpus = 2;
	176	#else
	177	unsigned int nr_pcpus = num_possible_cpus();
	178	#endif
	179	if (nr_pcpus >= 4)
	180	size = 512;
	181	if (nr_pcpus >= 8)
	182	size = 1024;
	183	if (nr_pcpus >= 16)
	184	size = 2048;
	185	if (nr_pcpus >= 32)
	186	size = 4096;
94cd3e6c	187	if (sizeof(spinlock_t) != 0) {
230140cf	188	#ifdef CONFIG_NUMA
9db66bdc ED	189	if (size * sizeof(spinlock_t) > PAGE_SIZE)
9db66bdc ED	190	hashinfo->ehash_locks = vmalloc(size * sizeof(spinlock_t));
230140cf ED	191	else
230140cf ED	192	#endif
9db66bdc	193	hashinfo->ehash_locks = kmalloc(size * sizeof(spinlock_t),
230140cf ED	194	GFP_KERNEL);
	195	if (!hashinfo->ehash_locks)
	196	return ENOMEM;
	197	for (i = 0; i < size; i++)
9db66bdc	198	spin_lock_init(&hashinfo->ehash_locks[i]);
230140cf ED	199	}
	200	hashinfo->ehash_locks_mask = size - 1;
	201	return 0;
	202	}
	203
	204	static inline void inet_ehash_locks_free(struct inet_hashinfo *hashinfo)
	205	{
	206	if (hashinfo->ehash_locks) {
	207	#ifdef CONFIG_NUMA
	208	unsigned int size = (hashinfo->ehash_locks_mask + 1) *
9db66bdc	209	sizeof(spinlock_t);
230140cf ED	210	if (size > PAGE_SIZE)
	211	vfree(hashinfo->ehash_locks);
	212	else
230140cf	213	#endif
218ad12f	214	kfree(hashinfo->ehash_locks);
230140cf ED	215	hashinfo->ehash_locks = NULL;
	216	}
	217	}
	218
1fd51155 JP	219	struct inet_bind_bucket *
	220	inet_bind_bucket_create(struct kmem_cache cachep, struct net net,
	221	struct inet_bind_hashbucket *head,
	222	const unsigned short snum);
	223	void inet_bind_bucket_destroy(struct kmem_cache *cachep,
	224	struct inet_bind_bucket *tb);
	225
	226	static inline int inet_bhashfn(struct net *net, const __u16 lport,
	227	const int bhash_size)
77d8bf9c	228	{
0b441916	229	return (lport + net_hash_mix(net)) & (bhash_size - 1);
77d8bf9c ACM	230	}
77d8bf9c ACM	231
1fd51155 JP	232	void inet_bind_hash(struct sock sk, struct inet_bind_bucket tb,
1fd51155 JP	233	const unsigned short snum);
2d8c4ce5	234
77d8bf9c	235	/* These can have wildcards, don't try too hard. */
2086a650	236	static inline int inet_lhashfn(struct net *net, const unsigned short num)
77d8bf9c	237	{
0b441916	238	return (num + net_hash_mix(net)) & (INET_LHTABLE_SIZE - 1);
77d8bf9c ACM	239	}
	240
	241	static inline int inet_sk_listen_hashfn(const struct sock *sk)
	242	{
c720c7e8	243	return inet_lhashfn(sock_net(sk), inet_sk(sk)->inet_num);
77d8bf9c ACM	244	}
77d8bf9c ACM	245
2d8c4ce5	246	/* Caller must disable local BH processing. */
1fd51155	247	int __inet_inherit_port(struct sock sk, struct sock child);
2d8c4ce5	248
1fd51155	249	void inet_put_port(struct sock *sk);
2d8c4ce5	250
5caea4ea	251	void inet_hashinfo_init(struct inet_hashinfo *h);
f3f05f70	252
1fd51155 JP	253	int __inet_hash_nolisten(struct sock sk, struct inet_timewait_sock tw);
	254	void inet_hash(struct sock *sk);
	255	void inet_unhash(struct sock *sk);
33b62231	256
1fd51155 JP	257	struct sock __inet_lookup_listener(struct net net,
	258	struct inet_hashinfo *hashinfo,
	259	const __be32 saddr, const __be16 sport,
	260	const __be32 daddr,
	261	const unsigned short hnum,
	262	const int dif);
8f491069	263
c67499c0 PE	264	static inline struct sock inet_lookup_listener(struct net net,
c67499c0 PE	265	struct inet_hashinfo *hashinfo,
da5e3630	266	__be32 saddr, __be16 sport,
c67499c0	267	__be32 daddr, __be16 dport, int dif)
8f491069	268	{
da5e3630 TH	269	return __inet_lookup_listener(net, hashinfo, saddr, sport,
da5e3630 TH	270	daddr, ntohs(dport), dif);
8f491069	271	}
8feaf0c0 ACM	272
8feaf0c0 ACM	273	/* Socket demux engine toys. */
4f765d84 AV	274	/* What happens here is ugly; there's a pair of adjacent fields in
	275	struct inet_sock; __be16 dport followed by __u16 num. We want to
	276	search by pair, so we combine the keys into a single 32bit value
	277	and compare with 32bit value read from &...->dport. Let's at least
	278	make sure that it's not mixed with anything else...
	279	On 64bit targets we combine comparisons with pair of adjacent __be32
	280	fields in the same way.
	281	*/
8feaf0c0 ACM	282	#ifdef __BIG_ENDIAN
8feaf0c0 ACM	283	#define INET_COMBINED_PORTS(__sport, __dport) \
4f765d84	284	((__force __portpair)(((__force __u32)(__be16)(__sport) << 16) \| (__u32)(__dport)))
8feaf0c0 ACM	285	#else /* __LITTLE_ENDIAN */
8feaf0c0 ACM	286	#define INET_COMBINED_PORTS(__sport, __dport) \
4f765d84	287	((__force __portpair)(((__u32)(__dport) << 16) \| (__force __u32)(__be16)(__sport)))
8feaf0c0 ACM	288	#endif
	289
	290	#if (BITS_PER_LONG == 64)
	291	#ifdef __BIG_ENDIAN
	292	#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
4f765d84 AV	293	const __addrpair __name = (__force __addrpair) ( \
4f765d84 AV	294	(((__force __u64)(__be32)(__saddr)) << 32) \| \
c7228317	295	((__force __u64)(__be32)(__daddr)))
8feaf0c0 ACM	296	#else /* __LITTLE_ENDIAN */
8feaf0c0 ACM	297	#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
4f765d84 AV	298	const __addrpair __name = (__force __addrpair) ( \
4f765d84 AV	299	(((__force __u64)(__be32)(__daddr)) << 32) \| \
c7228317	300	((__force __u64)(__be32)(__saddr)))
8feaf0c0	301	#endif /* __BIG_ENDIAN */
ce43b03e	302	#define INET_MATCH(__sk, __net, __cookie, __saddr, __daddr, __ports, __dif) \
50805466 ED	303	(((__sk)->sk_portpair == (__ports)) && \
50805466 ED	304	((__sk)->sk_addrpair == (__cookie)) && \
ce43b03e ED	305	(!(__sk)->sk_bound_dev_if \|\| \
	306	((__sk)->sk_bound_dev_if == (__dif))) && \
	307	net_eq(sock_net(__sk), (__net)))
8feaf0c0	308	#else /* 32-bit arch */
c7228317 JP	309	#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
	310	const int __name __deprecated __attribute__((unused))
	311
ce43b03e	312	#define INET_MATCH(__sk, __net, __cookie, __saddr, __daddr, __ports, __dif) \
50805466 ED	313	(((__sk)->sk_portpair == (__ports)) && \
	314	((__sk)->sk_daddr == (__saddr)) && \
	315	((__sk)->sk_rcv_saddr == (__daddr)) && \
ce43b03e ED	316	(!(__sk)->sk_bound_dev_if \|\| \
	317	((__sk)->sk_bound_dev_if == (__dif))) && \
	318	net_eq(sock_net(__sk), (__net)))
8feaf0c0	319	#endif /* 64-bit arch */
e48c414e ACM	320
	321	/*
	322	* Sockets in TCP_CLOSE state are _always_ taken out of the hash, so we need
	323	* not check it for lookups anymore, thanks Alexey. -DaveM
	324	*
	325	* Local BH must be disabled here.
	326	*/
1fd51155 JP	327	struct sock __inet_lookup_established(struct net net,
	328	struct inet_hashinfo *hashinfo,
	329	const __be32 saddr, const __be16 sport,
	330	const __be32 daddr, const u16 hnum,
	331	const int dif);
e48c414e	332
8f491069	333	static inline struct sock *
c67499c0	334	inet_lookup_established(struct net net, struct inet_hashinfo hashinfo,
fb99c848 AV	335	const __be32 saddr, const __be16 sport,
fb99c848 AV	336	const __be32 daddr, const __be16 dport,
8f491069 HX	337	const int dif)
8f491069 HX	338	{
c67499c0	339	return __inet_lookup_established(net, hashinfo, saddr, sport, daddr,
8f491069 HX	340	ntohs(dport), dif);
	341	}
	342
c67499c0 PE	343	static inline struct sock __inet_lookup(struct net net,
c67499c0 PE	344	struct inet_hashinfo *hashinfo,
fb99c848 AV	345	const __be32 saddr, const __be16 sport,
fb99c848 AV	346	const __be32 daddr, const __be16 dport,
e48c414e ACM	347	const int dif)
e48c414e ACM	348	{
8f491069	349	u16 hnum = ntohs(dport);
c67499c0 PE	350	struct sock *sk = __inet_lookup_established(net, hashinfo,
	351	saddr, sport, daddr, hnum, dif);
	352
da5e3630 TH	353	return sk ? : __inet_lookup_listener(net, hashinfo, saddr, sport,
da5e3630 TH	354	daddr, hnum, dif);
e48c414e ACM	355	}
e48c414e ACM	356
c67499c0 PE	357	static inline struct sock inet_lookup(struct net net,
c67499c0 PE	358	struct inet_hashinfo *hashinfo,
fb99c848 AV	359	const __be32 saddr, const __be16 sport,
fb99c848 AV	360	const __be32 daddr, const __be16 dport,
e48c414e ACM	361	const int dif)
	362	{
	363	struct sock *sk;
	364
	365	local_bh_disable();
c67499c0	366	sk = __inet_lookup(net, hashinfo, saddr, sport, daddr, dport, dif);
e48c414e ACM	367	local_bh_enable();
	368
	369	return sk;
	370	}
a7f5e7f1	371
9a1f27c4 ACM	372	static inline struct sock __inet_lookup_skb(struct inet_hashinfo hashinfo,
	373	struct sk_buff *skb,
	374	const __be16 sport,
	375	const __be16 dport)
	376	{
41063e9d	377	struct sock *sk = skb_steal_sock(skb);
9a1f27c4 ACM	378	const struct iphdr *iph = ip_hdr(skb);
9a1f27c4 ACM	379
41063e9d	380	if (sk)
23542618 KK	381	return sk;
23542618 KK	382	else
adf30907	383	return __inet_lookup(dev_net(skb_dst(skb)->dev), hashinfo,
23542618 KK	384	iph->saddr, sport,
23542618 KK	385	iph->daddr, dport, inet_iif(skb));
9a1f27c4 ACM	386	}
9a1f27c4 ACM	387
1fd51155 JP	388	int __inet_hash_connect(struct inet_timewait_death_row *death_row,
	389	struct sock *sk, u32 port_offset,
	390	int (check_established)(struct inet_timewait_death_row ,
	391	struct sock *, __u16,
	392	struct inet_timewait_sock **),
	393	int (hash)(struct sock sk,
	394	struct inet_timewait_sock *twp));
9327f705	395
1fd51155 JP	396	int inet_hash_connect(struct inet_timewait_death_row *death_row,
1fd51155 JP	397	struct sock *sk);
304a1618	398	#endif /* _INET_HASHTABLES_H */