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v4.6
 
  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
 17
 18#include <linux/interrupt.h>
 19#include <linux/ip.h>
 20#include <linux/ipv6.h>
 21#include <linux/list.h>
 22#include <linux/slab.h>
 23#include <linux/socket.h>
 24#include <linux/spinlock.h>
 25#include <linux/types.h>
 26#include <linux/wait.h>
 27
 28#include <net/inet_connection_sock.h>
 29#include <net/inet_sock.h>
 30#include <net/sock.h>
 31#include <net/route.h>
 32#include <net/tcp_states.h>
 33#include <net/netns/hash.h>
 34
 35#include <linux/atomic.h>
 36#include <asm/byteorder.h>
 37
 38/* This is for all connections with a full identity, no wildcards.
 39 * The 'e' prefix stands for Establish, but we really put all sockets
 40 * but LISTEN ones.
 41 */
 42struct inet_ehash_bucket {
 43	struct hlist_nulls_head chain;
 44};
 45
 46/* There are a few simple rules, which allow for local port reuse by
 47 * an application.  In essence:
 48 *
 49 *	1) Sockets bound to different interfaces may share a local port.
 50 *	   Failing that, goto test 2.
 51 *	2) If all sockets have sk->sk_reuse set, and none of them are in
 52 *	   TCP_LISTEN state, the port may be shared.
 53 *	   Failing that, goto test 3.
 54 *	3) If all sockets are bound to a specific inet_sk(sk)->rcv_saddr local
 55 *	   address, and none of them are the same, the port may be
 56 *	   shared.
 57 *	   Failing this, the port cannot be shared.
 58 *
 59 * The interesting point, is test #2.  This is what an FTP server does
 60 * all day.  To optimize this case we use a specific flag bit defined
 61 * below.  As we add sockets to a bind bucket list, we perform a
 62 * check of: (newsk->sk_reuse && (newsk->sk_state != TCP_LISTEN))
 63 * As long as all sockets added to a bind bucket pass this test,
 64 * the flag bit will be set.
 65 * The resulting situation is that tcp_v[46]_verify_bind() can just check
 66 * for this flag bit, if it is set and the socket trying to bind has
 67 * sk->sk_reuse set, we don't even have to walk the owners list at all,
 68 * we return that it is ok to bind this socket to the requested local port.
 69 *
 70 * Sounds like a lot of work, but it is worth it.  In a more naive
 71 * implementation (ie. current FreeBSD etc.) the entire list of ports
 72 * must be walked for each data port opened by an ftp server.  Needless
 73 * to say, this does not scale at all.  With a couple thousand FTP
 74 * users logged onto your box, isn't it nice to know that new data
 75 * ports are created in O(1) time?  I thought so. ;-)	-DaveM
 76 */
 
 
 
 77struct inet_bind_bucket {
 78	possible_net_t		ib_net;
 
 79	unsigned short		port;
 80	signed char		fastreuse;
 81	signed char		fastreuseport;
 82	kuid_t			fastuid;
 83	int			num_owners;
 
 
 
 
 
 84	struct hlist_node	node;
 85	struct hlist_head	owners;
 86};
 87
 88static inline struct net *ib_net(struct inet_bind_bucket *ib)
 89{
 90	return read_pnet(&ib->ib_net);
 91}
 92
 93#define inet_bind_bucket_for_each(tb, head) \
 94	hlist_for_each_entry(tb, head, node)
 95
 96struct inet_bind_hashbucket {
 97	spinlock_t		lock;
 98	struct hlist_head	chain;
 99};
100
101/*
102 * Sockets can be hashed in established or listening table
103 * We must use different 'nulls' end-of-chain value for listening
104 * hash table, or we might find a socket that was closed and
105 * reallocated/inserted into established hash table
106 */
107#define LISTENING_NULLS_BASE (1U << 29)
108struct inet_listen_hashbucket {
109	spinlock_t		lock;
110	struct hlist_nulls_head	head;
 
 
 
 
111};
112
113/* This is for listening sockets, thus all sockets which possess wildcards. */
114#define INET_LHTABLE_SIZE	32	/* Yes, really, this is all you need. */
115
116struct inet_hashinfo {
117	/* This is for sockets with full identity only.  Sockets here will
118	 * always be without wildcards and will have the following invariant:
119	 *
120	 *          TCP_ESTABLISHED <= sk->sk_state < TCP_CLOSE
121	 *
122	 */
123	struct inet_ehash_bucket	*ehash;
124	spinlock_t			*ehash_locks;
125	unsigned int			ehash_mask;
126	unsigned int			ehash_locks_mask;
127
128	/* Ok, let's try this, I give up, we do need a local binding
129	 * TCP hash as well as the others for fast bind/connect.
130	 */
 
131	struct inet_bind_hashbucket	*bhash;
132
133	unsigned int			bhash_size;
134	/* 4 bytes hole on 64 bit */
135
136	struct kmem_cache		*bind_bucket_cachep;
 
 
137
138	/* All the above members are written once at bootup and
139	 * never written again _or_ are predominantly read-access.
140	 *
141	 * Now align to a new cache line as all the following members
142	 * might be often dirty.
143	 */
144	/* All sockets in TCP_LISTEN state will be in here.  This is the only
145	 * table where wildcard'd TCP sockets can exist.  Hash function here
146	 * is just local port number.
 
 
147	 */
148	struct inet_listen_hashbucket	listening_hash[INET_LHTABLE_SIZE]
149					____cacheline_aligned_in_smp;
150};
151
 
 
 
 
 
 
 
 
 
152static inline struct inet_ehash_bucket *inet_ehash_bucket(
153	struct inet_hashinfo *hashinfo,
154	unsigned int hash)
155{
156	return &hashinfo->ehash[hash & hashinfo->ehash_mask];
157}
158
159static inline spinlock_t *inet_ehash_lockp(
160	struct inet_hashinfo *hashinfo,
161	unsigned int hash)
162{
163	return &hashinfo->ehash_locks[hash & hashinfo->ehash_locks_mask];
164}
165
166int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo);
167
 
 
 
 
 
 
168static inline void inet_ehash_locks_free(struct inet_hashinfo *hashinfo)
169{
170	kvfree(hashinfo->ehash_locks);
171	hashinfo->ehash_locks = NULL;
172}
173
 
 
 
 
 
 
 
 
 
 
 
174struct inet_bind_bucket *
175inet_bind_bucket_create(struct kmem_cache *cachep, struct net *net,
176			struct inet_bind_hashbucket *head,
177			const unsigned short snum);
178void inet_bind_bucket_destroy(struct kmem_cache *cachep,
179			      struct inet_bind_bucket *tb);
180
181static inline u32 inet_bhashfn(const struct net *net, const __u16 lport,
182			       const u32 bhash_size)
183{
184	return (lport + net_hash_mix(net)) & (bhash_size - 1);
185}
186
187void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
188		    const unsigned short snum);
189
190/* These can have wildcards, don't try too hard. */
191static inline u32 inet_lhashfn(const struct net *net, const unsigned short num)
192{
193	return (num + net_hash_mix(net)) & (INET_LHTABLE_SIZE - 1);
194}
195
196static inline int inet_sk_listen_hashfn(const struct sock *sk)
197{
198	return inet_lhashfn(sock_net(sk), inet_sk(sk)->inet_num);
199}
200
201/* Caller must disable local BH processing. */
202int __inet_inherit_port(const struct sock *sk, struct sock *child);
203
204void inet_put_port(struct sock *sk);
205
206void inet_hashinfo_init(struct inet_hashinfo *h);
 
 
 
 
 
207
208bool inet_ehash_insert(struct sock *sk, struct sock *osk);
209bool inet_ehash_nolisten(struct sock *sk, struct sock *osk);
210int __inet_hash(struct sock *sk, struct sock *osk,
211		int (*saddr_same)(const struct sock *sk1,
212				  const struct sock *sk2,
213				  bool match_wildcard));
214int inet_hash(struct sock *sk);
215void inet_unhash(struct sock *sk);
216
217struct sock *__inet_lookup_listener(struct net *net,
218				    struct inet_hashinfo *hashinfo,
219				    struct sk_buff *skb, int doff,
220				    const __be32 saddr, const __be16 sport,
221				    const __be32 daddr,
222				    const unsigned short hnum,
223				    const int dif);
224
225static inline struct sock *inet_lookup_listener(struct net *net,
226		struct inet_hashinfo *hashinfo,
227		struct sk_buff *skb, int doff,
228		__be32 saddr, __be16 sport,
229		__be32 daddr, __be16 dport, int dif)
230{
231	return __inet_lookup_listener(net, hashinfo, skb, doff, saddr, sport,
232				      daddr, ntohs(dport), dif);
233}
234
235/* Socket demux engine toys. */
236/* What happens here is ugly; there's a pair of adjacent fields in
237   struct inet_sock; __be16 dport followed by __u16 num.  We want to
238   search by pair, so we combine the keys into a single 32bit value
239   and compare with 32bit value read from &...->dport.  Let's at least
240   make sure that it's not mixed with anything else...
241   On 64bit targets we combine comparisons with pair of adjacent __be32
242   fields in the same way.
243*/
244#ifdef __BIG_ENDIAN
245#define INET_COMBINED_PORTS(__sport, __dport) \
246	((__force __portpair)(((__force __u32)(__be16)(__sport) << 16) | (__u32)(__dport)))
247#else /* __LITTLE_ENDIAN */
248#define INET_COMBINED_PORTS(__sport, __dport) \
249	((__force __portpair)(((__u32)(__dport) << 16) | (__force __u32)(__be16)(__sport)))
250#endif
251
252#if (BITS_PER_LONG == 64)
253#ifdef __BIG_ENDIAN
254#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
255	const __addrpair __name = (__force __addrpair) ( \
256				   (((__force __u64)(__be32)(__saddr)) << 32) | \
257				   ((__force __u64)(__be32)(__daddr)))
258#else /* __LITTLE_ENDIAN */
259#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
260	const __addrpair __name = (__force __addrpair) ( \
261				   (((__force __u64)(__be32)(__daddr)) << 32) | \
262				   ((__force __u64)(__be32)(__saddr)))
263#endif /* __BIG_ENDIAN */
264#define INET_MATCH(__sk, __net, __cookie, __saddr, __daddr, __ports, __dif)	\
265	(((__sk)->sk_portpair == (__ports))			&&	\
266	 ((__sk)->sk_addrpair == (__cookie))			&&	\
267	 (!(__sk)->sk_bound_dev_if	||				\
268	   ((__sk)->sk_bound_dev_if == (__dif))) 		&& 	\
269	 net_eq(sock_net(__sk), (__net)))
270#else /* 32-bit arch */
271#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
272	const int __name __deprecated __attribute__((unused))
273
274#define INET_MATCH(__sk, __net, __cookie, __saddr, __daddr, __ports, __dif) \
275	(((__sk)->sk_portpair == (__ports))		&&		\
276	 ((__sk)->sk_daddr	== (__saddr))		&&		\
277	 ((__sk)->sk_rcv_saddr	== (__daddr))		&&		\
278	 (!(__sk)->sk_bound_dev_if	||				\
279	   ((__sk)->sk_bound_dev_if == (__dif))) 	&&		\
280	 net_eq(sock_net(__sk), (__net)))
281#endif /* 64-bit arch */
282
283/*
284 * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so we need
285 * not check it for lookups anymore, thanks Alexey. -DaveM
286 *
287 * Local BH must be disabled here.
288 */
289struct sock *__inet_lookup_established(struct net *net,
290				       struct inet_hashinfo *hashinfo,
291				       const __be32 saddr, const __be16 sport,
292				       const __be32 daddr, const u16 hnum,
293				       const int dif);
294
295static inline struct sock *
296	inet_lookup_established(struct net *net, struct inet_hashinfo *hashinfo,
297				const __be32 saddr, const __be16 sport,
298				const __be32 daddr, const __be16 dport,
299				const int dif)
300{
301	return __inet_lookup_established(net, hashinfo, saddr, sport, daddr,
302					 ntohs(dport), dif);
303}
304
305static inline struct sock *__inet_lookup(struct net *net,
306					 struct inet_hashinfo *hashinfo,
307					 struct sk_buff *skb, int doff,
308					 const __be32 saddr, const __be16 sport,
309					 const __be32 daddr, const __be16 dport,
310					 const int dif)
 
311{
312	u16 hnum = ntohs(dport);
313	struct sock *sk = __inet_lookup_established(net, hashinfo,
314				saddr, sport, daddr, hnum, dif);
315
316	return sk ? : __inet_lookup_listener(net, hashinfo, skb, doff, saddr,
317					     sport, daddr, hnum, dif);
 
 
 
 
 
 
318}
319
320static inline struct sock *inet_lookup(struct net *net,
321				       struct inet_hashinfo *hashinfo,
322				       struct sk_buff *skb, int doff,
323				       const __be32 saddr, const __be16 sport,
324				       const __be32 daddr, const __be16 dport,
325				       const int dif)
326{
327	struct sock *sk;
 
328
329	local_bh_disable();
330	sk = __inet_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
331			   dport, dif);
332	local_bh_enable();
333
 
 
334	return sk;
335}
336
337static inline struct sock *__inet_lookup_skb(struct inet_hashinfo *hashinfo,
338					     struct sk_buff *skb,
339					     int doff,
340					     const __be16 sport,
341					     const __be16 dport)
 
 
342{
343	struct sock *sk = skb_steal_sock(skb);
344	const struct iphdr *iph = ip_hdr(skb);
345
346	if (sk)
347		return sk;
348	else
349		return __inet_lookup(dev_net(skb_dst(skb)->dev), hashinfo, skb,
350				     doff, iph->saddr, sport,
351				     iph->daddr, dport, inet_iif(skb));
 
352}
353
354u32 sk_ehashfn(const struct sock *sk);
355u32 inet6_ehashfn(const struct net *net,
356		  const struct in6_addr *laddr, const u16 lport,
357		  const struct in6_addr *faddr, const __be16 fport);
358
359static inline void sk_daddr_set(struct sock *sk, __be32 addr)
360{
361	sk->sk_daddr = addr; /* alias of inet_daddr */
362#if IS_ENABLED(CONFIG_IPV6)
363	ipv6_addr_set_v4mapped(addr, &sk->sk_v6_daddr);
364#endif
365}
366
367static inline void sk_rcv_saddr_set(struct sock *sk, __be32 addr)
368{
369	sk->sk_rcv_saddr = addr; /* alias of inet_rcv_saddr */
370#if IS_ENABLED(CONFIG_IPV6)
371	ipv6_addr_set_v4mapped(addr, &sk->sk_v6_rcv_saddr);
372#endif
373}
374
375int __inet_hash_connect(struct inet_timewait_death_row *death_row,
376			struct sock *sk, u32 port_offset,
377			int (*check_established)(struct inet_timewait_death_row *,
378						 struct sock *, __u16,
379						 struct inet_timewait_sock **));
380
381int inet_hash_connect(struct inet_timewait_death_row *death_row,
382		      struct sock *sk);
383#endif /* _INET_HASHTABLES_H */
v5.9
  1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
  4 *		operating system.  INET is implemented using the BSD Socket
  5 *		interface as the means of communication with the user level.
  6 *
  7 * Authors:	Lotsa people, from code originally in tcp
 
 
 
 
 
  8 */
  9
 10#ifndef _INET_HASHTABLES_H
 11#define _INET_HASHTABLES_H
 12
 13
 14#include <linux/interrupt.h>
 15#include <linux/ip.h>
 16#include <linux/ipv6.h>
 17#include <linux/list.h>
 18#include <linux/slab.h>
 19#include <linux/socket.h>
 20#include <linux/spinlock.h>
 21#include <linux/types.h>
 22#include <linux/wait.h>
 23
 24#include <net/inet_connection_sock.h>
 25#include <net/inet_sock.h>
 26#include <net/sock.h>
 27#include <net/route.h>
 28#include <net/tcp_states.h>
 29#include <net/netns/hash.h>
 30
 31#include <linux/refcount.h>
 32#include <asm/byteorder.h>
 33
 34/* This is for all connections with a full identity, no wildcards.
 35 * The 'e' prefix stands for Establish, but we really put all sockets
 36 * but LISTEN ones.
 37 */
 38struct inet_ehash_bucket {
 39	struct hlist_nulls_head chain;
 40};
 41
 42/* There are a few simple rules, which allow for local port reuse by
 43 * an application.  In essence:
 44 *
 45 *	1) Sockets bound to different interfaces may share a local port.
 46 *	   Failing that, goto test 2.
 47 *	2) If all sockets have sk->sk_reuse set, and none of them are in
 48 *	   TCP_LISTEN state, the port may be shared.
 49 *	   Failing that, goto test 3.
 50 *	3) If all sockets are bound to a specific inet_sk(sk)->rcv_saddr local
 51 *	   address, and none of them are the same, the port may be
 52 *	   shared.
 53 *	   Failing this, the port cannot be shared.
 54 *
 55 * The interesting point, is test #2.  This is what an FTP server does
 56 * all day.  To optimize this case we use a specific flag bit defined
 57 * below.  As we add sockets to a bind bucket list, we perform a
 58 * check of: (newsk->sk_reuse && (newsk->sk_state != TCP_LISTEN))
 59 * As long as all sockets added to a bind bucket pass this test,
 60 * the flag bit will be set.
 61 * The resulting situation is that tcp_v[46]_verify_bind() can just check
 62 * for this flag bit, if it is set and the socket trying to bind has
 63 * sk->sk_reuse set, we don't even have to walk the owners list at all,
 64 * we return that it is ok to bind this socket to the requested local port.
 65 *
 66 * Sounds like a lot of work, but it is worth it.  In a more naive
 67 * implementation (ie. current FreeBSD etc.) the entire list of ports
 68 * must be walked for each data port opened by an ftp server.  Needless
 69 * to say, this does not scale at all.  With a couple thousand FTP
 70 * users logged onto your box, isn't it nice to know that new data
 71 * ports are created in O(1) time?  I thought so. ;-)	-DaveM
 72 */
 73#define FASTREUSEPORT_ANY	1
 74#define FASTREUSEPORT_STRICT	2
 75
 76struct inet_bind_bucket {
 77	possible_net_t		ib_net;
 78	int			l3mdev;
 79	unsigned short		port;
 80	signed char		fastreuse;
 81	signed char		fastreuseport;
 82	kuid_t			fastuid;
 83#if IS_ENABLED(CONFIG_IPV6)
 84	struct in6_addr		fast_v6_rcv_saddr;
 85#endif
 86	__be32			fast_rcv_saddr;
 87	unsigned short		fast_sk_family;
 88	bool			fast_ipv6_only;
 89	struct hlist_node	node;
 90	struct hlist_head	owners;
 91};
 92
 93static inline struct net *ib_net(struct inet_bind_bucket *ib)
 94{
 95	return read_pnet(&ib->ib_net);
 96}
 97
 98#define inet_bind_bucket_for_each(tb, head) \
 99	hlist_for_each_entry(tb, head, node)
100
101struct inet_bind_hashbucket {
102	spinlock_t		lock;
103	struct hlist_head	chain;
104};
105
106/* Sockets can be hashed in established or listening table.
107 * We must use different 'nulls' end-of-chain value for all hash buckets :
108 * A socket might transition from ESTABLISH to LISTEN state without
109 * RCU grace period. A lookup in ehash table needs to handle this case.
 
110 */
111#define LISTENING_NULLS_BASE (1U << 29)
112struct inet_listen_hashbucket {
113	spinlock_t		lock;
114	unsigned int		count;
115	union {
116		struct hlist_head	head;
117		struct hlist_nulls_head	nulls_head;
118	};
119};
120
121/* This is for listening sockets, thus all sockets which possess wildcards. */
122#define INET_LHTABLE_SIZE	32	/* Yes, really, this is all you need. */
123
124struct inet_hashinfo {
125	/* This is for sockets with full identity only.  Sockets here will
126	 * always be without wildcards and will have the following invariant:
127	 *
128	 *          TCP_ESTABLISHED <= sk->sk_state < TCP_CLOSE
129	 *
130	 */
131	struct inet_ehash_bucket	*ehash;
132	spinlock_t			*ehash_locks;
133	unsigned int			ehash_mask;
134	unsigned int			ehash_locks_mask;
135
136	/* Ok, let's try this, I give up, we do need a local binding
137	 * TCP hash as well as the others for fast bind/connect.
138	 */
139	struct kmem_cache		*bind_bucket_cachep;
140	struct inet_bind_hashbucket	*bhash;
 
141	unsigned int			bhash_size;
 
142
143	/* The 2nd listener table hashed by local port and address */
144	unsigned int			lhash2_mask;
145	struct inet_listen_hashbucket	*lhash2;
146
147	/* All the above members are written once at bootup and
148	 * never written again _or_ are predominantly read-access.
149	 *
150	 * Now align to a new cache line as all the following members
151	 * might be often dirty.
152	 */
153	/* All sockets in TCP_LISTEN state will be in listening_hash.
154	 * This is the only table where wildcard'd TCP sockets can
155	 * exist.  listening_hash is only hashed by local port number.
156	 * If lhash2 is initialized, the same socket will also be hashed
157	 * to lhash2 by port and address.
158	 */
159	struct inet_listen_hashbucket	listening_hash[INET_LHTABLE_SIZE]
160					____cacheline_aligned_in_smp;
161};
162
163#define inet_lhash2_for_each_icsk_rcu(__icsk, list) \
164	hlist_for_each_entry_rcu(__icsk, list, icsk_listen_portaddr_node)
165
166static inline struct inet_listen_hashbucket *
167inet_lhash2_bucket(struct inet_hashinfo *h, u32 hash)
168{
169	return &h->lhash2[hash & h->lhash2_mask];
170}
171
172static inline struct inet_ehash_bucket *inet_ehash_bucket(
173	struct inet_hashinfo *hashinfo,
174	unsigned int hash)
175{
176	return &hashinfo->ehash[hash & hashinfo->ehash_mask];
177}
178
179static inline spinlock_t *inet_ehash_lockp(
180	struct inet_hashinfo *hashinfo,
181	unsigned int hash)
182{
183	return &hashinfo->ehash_locks[hash & hashinfo->ehash_locks_mask];
184}
185
186int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo);
187
188static inline void inet_hashinfo2_free_mod(struct inet_hashinfo *h)
189{
190	kfree(h->lhash2);
191	h->lhash2 = NULL;
192}
193
194static inline void inet_ehash_locks_free(struct inet_hashinfo *hashinfo)
195{
196	kvfree(hashinfo->ehash_locks);
197	hashinfo->ehash_locks = NULL;
198}
199
200static inline bool inet_sk_bound_dev_eq(struct net *net, int bound_dev_if,
201					int dif, int sdif)
202{
203#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
204	return inet_bound_dev_eq(!!net->ipv4.sysctl_tcp_l3mdev_accept,
205				 bound_dev_if, dif, sdif);
206#else
207	return inet_bound_dev_eq(true, bound_dev_if, dif, sdif);
208#endif
209}
210
211struct inet_bind_bucket *
212inet_bind_bucket_create(struct kmem_cache *cachep, struct net *net,
213			struct inet_bind_hashbucket *head,
214			const unsigned short snum, int l3mdev);
215void inet_bind_bucket_destroy(struct kmem_cache *cachep,
216			      struct inet_bind_bucket *tb);
217
218static inline u32 inet_bhashfn(const struct net *net, const __u16 lport,
219			       const u32 bhash_size)
220{
221	return (lport + net_hash_mix(net)) & (bhash_size - 1);
222}
223
224void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
225		    const unsigned short snum);
226
227/* These can have wildcards, don't try too hard. */
228static inline u32 inet_lhashfn(const struct net *net, const unsigned short num)
229{
230	return (num + net_hash_mix(net)) & (INET_LHTABLE_SIZE - 1);
231}
232
233static inline int inet_sk_listen_hashfn(const struct sock *sk)
234{
235	return inet_lhashfn(sock_net(sk), inet_sk(sk)->inet_num);
236}
237
238/* Caller must disable local BH processing. */
239int __inet_inherit_port(const struct sock *sk, struct sock *child);
240
241void inet_put_port(struct sock *sk);
242
243void inet_hashinfo_init(struct inet_hashinfo *h);
244void inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
245			 unsigned long numentries, int scale,
246			 unsigned long low_limit,
247			 unsigned long high_limit);
248int inet_hashinfo2_init_mod(struct inet_hashinfo *h);
249
250bool inet_ehash_insert(struct sock *sk, struct sock *osk);
251bool inet_ehash_nolisten(struct sock *sk, struct sock *osk);
252int __inet_hash(struct sock *sk, struct sock *osk);
 
 
 
253int inet_hash(struct sock *sk);
254void inet_unhash(struct sock *sk);
255
256struct sock *__inet_lookup_listener(struct net *net,
257				    struct inet_hashinfo *hashinfo,
258				    struct sk_buff *skb, int doff,
259				    const __be32 saddr, const __be16 sport,
260				    const __be32 daddr,
261				    const unsigned short hnum,
262				    const int dif, const int sdif);
263
264static inline struct sock *inet_lookup_listener(struct net *net,
265		struct inet_hashinfo *hashinfo,
266		struct sk_buff *skb, int doff,
267		__be32 saddr, __be16 sport,
268		__be32 daddr, __be16 dport, int dif, int sdif)
269{
270	return __inet_lookup_listener(net, hashinfo, skb, doff, saddr, sport,
271				      daddr, ntohs(dport), dif, sdif);
272}
273
274/* Socket demux engine toys. */
275/* What happens here is ugly; there's a pair of adjacent fields in
276   struct inet_sock; __be16 dport followed by __u16 num.  We want to
277   search by pair, so we combine the keys into a single 32bit value
278   and compare with 32bit value read from &...->dport.  Let's at least
279   make sure that it's not mixed with anything else...
280   On 64bit targets we combine comparisons with pair of adjacent __be32
281   fields in the same way.
282*/
283#ifdef __BIG_ENDIAN
284#define INET_COMBINED_PORTS(__sport, __dport) \
285	((__force __portpair)(((__force __u32)(__be16)(__sport) << 16) | (__u32)(__dport)))
286#else /* __LITTLE_ENDIAN */
287#define INET_COMBINED_PORTS(__sport, __dport) \
288	((__force __portpair)(((__u32)(__dport) << 16) | (__force __u32)(__be16)(__sport)))
289#endif
290
291#if (BITS_PER_LONG == 64)
292#ifdef __BIG_ENDIAN
293#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
294	const __addrpair __name = (__force __addrpair) ( \
295				   (((__force __u64)(__be32)(__saddr)) << 32) | \
296				   ((__force __u64)(__be32)(__daddr)))
297#else /* __LITTLE_ENDIAN */
298#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
299	const __addrpair __name = (__force __addrpair) ( \
300				   (((__force __u64)(__be32)(__daddr)) << 32) | \
301				   ((__force __u64)(__be32)(__saddr)))
302#endif /* __BIG_ENDIAN */
303#define INET_MATCH(__sk, __net, __cookie, __saddr, __daddr, __ports, __dif, __sdif) \
304	(((__sk)->sk_portpair == (__ports))			&&	\
305	 ((__sk)->sk_addrpair == (__cookie))			&&	\
306	 (((__sk)->sk_bound_dev_if == (__dif))			||	\
307	  ((__sk)->sk_bound_dev_if == (__sdif)))		&&	\
308	 net_eq(sock_net(__sk), (__net)))
309#else /* 32-bit arch */
310#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
311	const int __name __deprecated __attribute__((unused))
312
313#define INET_MATCH(__sk, __net, __cookie, __saddr, __daddr, __ports, __dif, __sdif) \
314	(((__sk)->sk_portpair == (__ports))		&&		\
315	 ((__sk)->sk_daddr	== (__saddr))		&&		\
316	 ((__sk)->sk_rcv_saddr	== (__daddr))		&&		\
317	 (((__sk)->sk_bound_dev_if == (__dif))		||		\
318	  ((__sk)->sk_bound_dev_if == (__sdif)))	&&		\
319	 net_eq(sock_net(__sk), (__net)))
320#endif /* 64-bit arch */
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 */
325struct sock *__inet_lookup_established(struct net *net,
326				       struct inet_hashinfo *hashinfo,
327				       const __be32 saddr, const __be16 sport,
328				       const __be32 daddr, const u16 hnum,
329				       const int dif, const int sdif);
330
331static inline struct sock *
332	inet_lookup_established(struct net *net, struct inet_hashinfo *hashinfo,
333				const __be32 saddr, const __be16 sport,
334				const __be32 daddr, const __be16 dport,
335				const int dif)
336{
337	return __inet_lookup_established(net, hashinfo, saddr, sport, daddr,
338					 ntohs(dport), dif, 0);
339}
340
341static inline struct sock *__inet_lookup(struct net *net,
342					 struct inet_hashinfo *hashinfo,
343					 struct sk_buff *skb, int doff,
344					 const __be32 saddr, const __be16 sport,
345					 const __be32 daddr, const __be16 dport,
346					 const int dif, const int sdif,
347					 bool *refcounted)
348{
349	u16 hnum = ntohs(dport);
350	struct sock *sk;
 
351
352	sk = __inet_lookup_established(net, hashinfo, saddr, sport,
353				       daddr, hnum, dif, sdif);
354	*refcounted = true;
355	if (sk)
356		return sk;
357	*refcounted = false;
358	return __inet_lookup_listener(net, hashinfo, skb, doff, saddr,
359				      sport, daddr, hnum, dif, sdif);
360}
361
362static inline struct sock *inet_lookup(struct net *net,
363				       struct inet_hashinfo *hashinfo,
364				       struct sk_buff *skb, int doff,
365				       const __be32 saddr, const __be16 sport,
366				       const __be32 daddr, const __be16 dport,
367				       const int dif)
368{
369	struct sock *sk;
370	bool refcounted;
371
 
372	sk = __inet_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
373			   dport, dif, 0, &refcounted);
 
374
375	if (sk && !refcounted && !refcount_inc_not_zero(&sk->sk_refcnt))
376		sk = NULL;
377	return sk;
378}
379
380static inline struct sock *__inet_lookup_skb(struct inet_hashinfo *hashinfo,
381					     struct sk_buff *skb,
382					     int doff,
383					     const __be16 sport,
384					     const __be16 dport,
385					     const int sdif,
386					     bool *refcounted)
387{
388	struct sock *sk = skb_steal_sock(skb, refcounted);
389	const struct iphdr *iph = ip_hdr(skb);
390
391	if (sk)
392		return sk;
393
394	return __inet_lookup(dev_net(skb_dst(skb)->dev), hashinfo, skb,
395			     doff, iph->saddr, sport,
396			     iph->daddr, dport, inet_iif(skb), sdif,
397			     refcounted);
398}
399
 
400u32 inet6_ehashfn(const struct net *net,
401		  const struct in6_addr *laddr, const u16 lport,
402		  const struct in6_addr *faddr, const __be16 fport);
403
404static inline void sk_daddr_set(struct sock *sk, __be32 addr)
405{
406	sk->sk_daddr = addr; /* alias of inet_daddr */
407#if IS_ENABLED(CONFIG_IPV6)
408	ipv6_addr_set_v4mapped(addr, &sk->sk_v6_daddr);
409#endif
410}
411
412static inline void sk_rcv_saddr_set(struct sock *sk, __be32 addr)
413{
414	sk->sk_rcv_saddr = addr; /* alias of inet_rcv_saddr */
415#if IS_ENABLED(CONFIG_IPV6)
416	ipv6_addr_set_v4mapped(addr, &sk->sk_v6_rcv_saddr);
417#endif
418}
419
420int __inet_hash_connect(struct inet_timewait_death_row *death_row,
421			struct sock *sk, u32 port_offset,
422			int (*check_established)(struct inet_timewait_death_row *,
423						 struct sock *, __u16,
424						 struct inet_timewait_sock **));
425
426int inet_hash_connect(struct inet_timewait_death_row *death_row,
427		      struct sock *sk);
428#endif /* _INET_HASHTABLES_H */