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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 */
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/ip.h>
27#include <net/sock.h>
28#include <net/route.h>
29#include <net/tcp_states.h>
30#include <net/netns/hash.h>
31
32#include <linux/refcount.h>
33#include <asm/byteorder.h>
34
35/* This is for all connections with a full identity, no wildcards.
36 * The 'e' prefix stands for Establish, but we really put all sockets
37 * but LISTEN ones.
38 */
39struct inet_ehash_bucket {
40 struct hlist_nulls_head chain;
41};
42
43/* There are a few simple rules, which allow for local port reuse by
44 * an application. In essence:
45 *
46 * 1) Sockets bound to different interfaces may share a local port.
47 * Failing that, goto test 2.
48 * 2) If all sockets have sk->sk_reuse set, and none of them are in
49 * TCP_LISTEN state, the port may be shared.
50 * Failing that, goto test 3.
51 * 3) If all sockets are bound to a specific inet_sk(sk)->rcv_saddr local
52 * address, and none of them are the same, the port may be
53 * shared.
54 * Failing this, the port cannot be shared.
55 *
56 * The interesting point, is test #2. This is what an FTP server does
57 * all day. To optimize this case we use a specific flag bit defined
58 * below. As we add sockets to a bind bucket list, we perform a
59 * check of: (newsk->sk_reuse && (newsk->sk_state != TCP_LISTEN))
60 * As long as all sockets added to a bind bucket pass this test,
61 * the flag bit will be set.
62 * The resulting situation is that tcp_v[46]_verify_bind() can just check
63 * for this flag bit, if it is set and the socket trying to bind has
64 * sk->sk_reuse set, we don't even have to walk the owners list at all,
65 * we return that it is ok to bind this socket to the requested local port.
66 *
67 * Sounds like a lot of work, but it is worth it. In a more naive
68 * implementation (ie. current FreeBSD etc.) the entire list of ports
69 * must be walked for each data port opened by an ftp server. Needless
70 * to say, this does not scale at all. With a couple thousand FTP
71 * users logged onto your box, isn't it nice to know that new data
72 * ports are created in O(1) time? I thought so. ;-) -DaveM
73 */
74#define FASTREUSEPORT_ANY 1
75#define FASTREUSEPORT_STRICT 2
76
77struct inet_bind_bucket {
78 possible_net_t ib_net;
79 int l3mdev;
80 unsigned short port;
81 signed char fastreuse;
82 signed char fastreuseport;
83 kuid_t fastuid;
84#if IS_ENABLED(CONFIG_IPV6)
85 struct in6_addr fast_v6_rcv_saddr;
86#endif
87 __be32 fast_rcv_saddr;
88 unsigned short fast_sk_family;
89 bool fast_ipv6_only;
90 struct hlist_node node;
91 struct hlist_head owners;
92};
93
94struct inet_bind2_bucket {
95 possible_net_t ib_net;
96 int l3mdev;
97 unsigned short port;
98#if IS_ENABLED(CONFIG_IPV6)
99 unsigned short family;
100#endif
101 union {
102#if IS_ENABLED(CONFIG_IPV6)
103 struct in6_addr v6_rcv_saddr;
104#endif
105 __be32 rcv_saddr;
106 };
107 /* Node in the bhash2 inet_bind_hashbucket chain */
108 struct hlist_node node;
109 /* List of sockets hashed to this bucket */
110 struct hlist_head owners;
111 /* bhash has twsk in owners, but bhash2 has twsk in
112 * deathrow not to add a member in struct sock_common.
113 */
114 struct hlist_head deathrow;
115};
116
117static inline struct net *ib_net(const struct inet_bind_bucket *ib)
118{
119 return read_pnet(&ib->ib_net);
120}
121
122static inline struct net *ib2_net(const struct inet_bind2_bucket *ib)
123{
124 return read_pnet(&ib->ib_net);
125}
126
127#define inet_bind_bucket_for_each(tb, head) \
128 hlist_for_each_entry(tb, head, node)
129
130struct inet_bind_hashbucket {
131 spinlock_t lock;
132 struct hlist_head chain;
133};
134
135/* Sockets can be hashed in established or listening table.
136 * We must use different 'nulls' end-of-chain value for all hash buckets :
137 * A socket might transition from ESTABLISH to LISTEN state without
138 * RCU grace period. A lookup in ehash table needs to handle this case.
139 */
140#define LISTENING_NULLS_BASE (1U << 29)
141struct inet_listen_hashbucket {
142 spinlock_t lock;
143 struct hlist_nulls_head nulls_head;
144};
145
146/* This is for listening sockets, thus all sockets which possess wildcards. */
147#define INET_LHTABLE_SIZE 32 /* Yes, really, this is all you need. */
148
149struct inet_hashinfo {
150 /* This is for sockets with full identity only. Sockets here will
151 * always be without wildcards and will have the following invariant:
152 *
153 * TCP_ESTABLISHED <= sk->sk_state < TCP_CLOSE
154 *
155 */
156 struct inet_ehash_bucket *ehash;
157 spinlock_t *ehash_locks;
158 unsigned int ehash_mask;
159 unsigned int ehash_locks_mask;
160
161 /* Ok, let's try this, I give up, we do need a local binding
162 * TCP hash as well as the others for fast bind/connect.
163 */
164 struct kmem_cache *bind_bucket_cachep;
165 /* This bind table is hashed by local port */
166 struct inet_bind_hashbucket *bhash;
167 struct kmem_cache *bind2_bucket_cachep;
168 /* This bind table is hashed by local port and sk->sk_rcv_saddr (ipv4)
169 * or sk->sk_v6_rcv_saddr (ipv6). This 2nd bind table is used
170 * primarily for expediting bind conflict resolution.
171 */
172 struct inet_bind_hashbucket *bhash2;
173 unsigned int bhash_size;
174
175 /* The 2nd listener table hashed by local port and address */
176 unsigned int lhash2_mask;
177 struct inet_listen_hashbucket *lhash2;
178
179 bool pernet;
180};
181
182static inline struct inet_hashinfo *tcp_or_dccp_get_hashinfo(const struct sock *sk)
183{
184#if IS_ENABLED(CONFIG_IP_DCCP)
185 return sk->sk_prot->h.hashinfo ? :
186 sock_net(sk)->ipv4.tcp_death_row.hashinfo;
187#else
188 return sock_net(sk)->ipv4.tcp_death_row.hashinfo;
189#endif
190}
191
192static inline struct inet_listen_hashbucket *
193inet_lhash2_bucket(struct inet_hashinfo *h, u32 hash)
194{
195 return &h->lhash2[hash & h->lhash2_mask];
196}
197
198static inline struct inet_ehash_bucket *inet_ehash_bucket(
199 struct inet_hashinfo *hashinfo,
200 unsigned int hash)
201{
202 return &hashinfo->ehash[hash & hashinfo->ehash_mask];
203}
204
205static inline spinlock_t *inet_ehash_lockp(
206 struct inet_hashinfo *hashinfo,
207 unsigned int hash)
208{
209 return &hashinfo->ehash_locks[hash & hashinfo->ehash_locks_mask];
210}
211
212int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo);
213
214static inline void inet_hashinfo2_free_mod(struct inet_hashinfo *h)
215{
216 kfree(h->lhash2);
217 h->lhash2 = NULL;
218}
219
220static inline void inet_ehash_locks_free(struct inet_hashinfo *hashinfo)
221{
222 kvfree(hashinfo->ehash_locks);
223 hashinfo->ehash_locks = NULL;
224}
225
226struct inet_hashinfo *inet_pernet_hashinfo_alloc(struct inet_hashinfo *hashinfo,
227 unsigned int ehash_entries);
228void inet_pernet_hashinfo_free(struct inet_hashinfo *hashinfo);
229
230struct inet_bind_bucket *
231inet_bind_bucket_create(struct kmem_cache *cachep, struct net *net,
232 struct inet_bind_hashbucket *head,
233 const unsigned short snum, int l3mdev);
234void inet_bind_bucket_destroy(struct kmem_cache *cachep,
235 struct inet_bind_bucket *tb);
236
237bool inet_bind_bucket_match(const struct inet_bind_bucket *tb,
238 const struct net *net, unsigned short port,
239 int l3mdev);
240
241struct inet_bind2_bucket *
242inet_bind2_bucket_create(struct kmem_cache *cachep, struct net *net,
243 struct inet_bind_hashbucket *head,
244 unsigned short port, int l3mdev,
245 const struct sock *sk);
246
247void inet_bind2_bucket_destroy(struct kmem_cache *cachep,
248 struct inet_bind2_bucket *tb);
249
250struct inet_bind2_bucket *
251inet_bind2_bucket_find(const struct inet_bind_hashbucket *head,
252 const struct net *net,
253 unsigned short port, int l3mdev,
254 const struct sock *sk);
255
256bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb,
257 const struct net *net, unsigned short port,
258 int l3mdev, const struct sock *sk);
259
260static inline u32 inet_bhashfn(const struct net *net, const __u16 lport,
261 const u32 bhash_size)
262{
263 return (lport + net_hash_mix(net)) & (bhash_size - 1);
264}
265
266static inline struct inet_bind_hashbucket *
267inet_bhashfn_portaddr(const struct inet_hashinfo *hinfo, const struct sock *sk,
268 const struct net *net, unsigned short port)
269{
270 u32 hash;
271
272#if IS_ENABLED(CONFIG_IPV6)
273 if (sk->sk_family == AF_INET6)
274 hash = ipv6_portaddr_hash(net, &sk->sk_v6_rcv_saddr, port);
275 else
276#endif
277 hash = ipv4_portaddr_hash(net, sk->sk_rcv_saddr, port);
278 return &hinfo->bhash2[hash & (hinfo->bhash_size - 1)];
279}
280
281struct inet_bind_hashbucket *
282inet_bhash2_addr_any_hashbucket(const struct sock *sk, const struct net *net, int port);
283
284/* This should be called whenever a socket's sk_rcv_saddr (ipv4) or
285 * sk_v6_rcv_saddr (ipv6) changes after it has been binded. The socket's
286 * rcv_saddr field should already have been updated when this is called.
287 */
288int inet_bhash2_update_saddr(struct sock *sk, void *saddr, int family);
289void inet_bhash2_reset_saddr(struct sock *sk);
290
291void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
292 struct inet_bind2_bucket *tb2, unsigned short port);
293
294/* Caller must disable local BH processing. */
295int __inet_inherit_port(const struct sock *sk, struct sock *child);
296
297void inet_put_port(struct sock *sk);
298
299void inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
300 unsigned long numentries, int scale,
301 unsigned long low_limit,
302 unsigned long high_limit);
303int inet_hashinfo2_init_mod(struct inet_hashinfo *h);
304
305bool inet_ehash_insert(struct sock *sk, struct sock *osk, bool *found_dup_sk);
306bool inet_ehash_nolisten(struct sock *sk, struct sock *osk,
307 bool *found_dup_sk);
308int __inet_hash(struct sock *sk, struct sock *osk);
309int inet_hash(struct sock *sk);
310void inet_unhash(struct sock *sk);
311
312struct sock *__inet_lookup_listener(struct net *net,
313 struct inet_hashinfo *hashinfo,
314 struct sk_buff *skb, int doff,
315 const __be32 saddr, const __be16 sport,
316 const __be32 daddr,
317 const unsigned short hnum,
318 const int dif, const int sdif);
319
320static inline struct sock *inet_lookup_listener(struct net *net,
321 struct inet_hashinfo *hashinfo,
322 struct sk_buff *skb, int doff,
323 __be32 saddr, __be16 sport,
324 __be32 daddr, __be16 dport, int dif, int sdif)
325{
326 return __inet_lookup_listener(net, hashinfo, skb, doff, saddr, sport,
327 daddr, ntohs(dport), dif, sdif);
328}
329
330/* Socket demux engine toys. */
331/* What happens here is ugly; there's a pair of adjacent fields in
332 struct inet_sock; __be16 dport followed by __u16 num. We want to
333 search by pair, so we combine the keys into a single 32bit value
334 and compare with 32bit value read from &...->dport. Let's at least
335 make sure that it's not mixed with anything else...
336 On 64bit targets we combine comparisons with pair of adjacent __be32
337 fields in the same way.
338*/
339#ifdef __BIG_ENDIAN
340#define INET_COMBINED_PORTS(__sport, __dport) \
341 ((__force __portpair)(((__force __u32)(__be16)(__sport) << 16) | (__u32)(__dport)))
342#else /* __LITTLE_ENDIAN */
343#define INET_COMBINED_PORTS(__sport, __dport) \
344 ((__force __portpair)(((__u32)(__dport) << 16) | (__force __u32)(__be16)(__sport)))
345#endif
346
347#ifdef __BIG_ENDIAN
348#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
349 const __addrpair __name = (__force __addrpair) ( \
350 (((__force __u64)(__be32)(__saddr)) << 32) | \
351 ((__force __u64)(__be32)(__daddr)))
352#else /* __LITTLE_ENDIAN */
353#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
354 const __addrpair __name = (__force __addrpair) ( \
355 (((__force __u64)(__be32)(__daddr)) << 32) | \
356 ((__force __u64)(__be32)(__saddr)))
357#endif /* __BIG_ENDIAN */
358
359static inline bool inet_match(struct net *net, const struct sock *sk,
360 const __addrpair cookie, const __portpair ports,
361 int dif, int sdif)
362{
363 if (!net_eq(sock_net(sk), net) ||
364 sk->sk_portpair != ports ||
365 sk->sk_addrpair != cookie)
366 return false;
367
368 /* READ_ONCE() paired with WRITE_ONCE() in sock_bindtoindex_locked() */
369 return inet_sk_bound_dev_eq(net, READ_ONCE(sk->sk_bound_dev_if), dif,
370 sdif);
371}
372
373/* Sockets in TCP_CLOSE state are _always_ taken out of the hash, so we need
374 * not check it for lookups anymore, thanks Alexey. -DaveM
375 */
376struct sock *__inet_lookup_established(struct net *net,
377 struct inet_hashinfo *hashinfo,
378 const __be32 saddr, const __be16 sport,
379 const __be32 daddr, const u16 hnum,
380 const int dif, const int sdif);
381
382static inline struct sock *
383 inet_lookup_established(struct net *net, struct inet_hashinfo *hashinfo,
384 const __be32 saddr, const __be16 sport,
385 const __be32 daddr, const __be16 dport,
386 const int dif)
387{
388 return __inet_lookup_established(net, hashinfo, saddr, sport, daddr,
389 ntohs(dport), dif, 0);
390}
391
392static inline struct sock *__inet_lookup(struct net *net,
393 struct inet_hashinfo *hashinfo,
394 struct sk_buff *skb, int doff,
395 const __be32 saddr, const __be16 sport,
396 const __be32 daddr, const __be16 dport,
397 const int dif, const int sdif,
398 bool *refcounted)
399{
400 u16 hnum = ntohs(dport);
401 struct sock *sk;
402
403 sk = __inet_lookup_established(net, hashinfo, saddr, sport,
404 daddr, hnum, dif, sdif);
405 *refcounted = true;
406 if (sk)
407 return sk;
408 *refcounted = false;
409 return __inet_lookup_listener(net, hashinfo, skb, doff, saddr,
410 sport, daddr, hnum, dif, sdif);
411}
412
413static inline struct sock *inet_lookup(struct net *net,
414 struct inet_hashinfo *hashinfo,
415 struct sk_buff *skb, int doff,
416 const __be32 saddr, const __be16 sport,
417 const __be32 daddr, const __be16 dport,
418 const int dif)
419{
420 struct sock *sk;
421 bool refcounted;
422
423 sk = __inet_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
424 dport, dif, 0, &refcounted);
425
426 if (sk && !refcounted && !refcount_inc_not_zero(&sk->sk_refcnt))
427 sk = NULL;
428 return sk;
429}
430
431static inline struct sock *__inet_lookup_skb(struct inet_hashinfo *hashinfo,
432 struct sk_buff *skb,
433 int doff,
434 const __be16 sport,
435 const __be16 dport,
436 const int sdif,
437 bool *refcounted)
438{
439 struct sock *sk = skb_steal_sock(skb, refcounted);
440 const struct iphdr *iph = ip_hdr(skb);
441
442 if (sk)
443 return sk;
444
445 return __inet_lookup(dev_net(skb_dst(skb)->dev), hashinfo, skb,
446 doff, iph->saddr, sport,
447 iph->daddr, dport, inet_iif(skb), sdif,
448 refcounted);
449}
450
451u32 inet6_ehashfn(const struct net *net,
452 const struct in6_addr *laddr, const u16 lport,
453 const struct in6_addr *faddr, const __be16 fport);
454
455static inline void sk_daddr_set(struct sock *sk, __be32 addr)
456{
457 sk->sk_daddr = addr; /* alias of inet_daddr */
458#if IS_ENABLED(CONFIG_IPV6)
459 ipv6_addr_set_v4mapped(addr, &sk->sk_v6_daddr);
460#endif
461}
462
463static inline void sk_rcv_saddr_set(struct sock *sk, __be32 addr)
464{
465 sk->sk_rcv_saddr = addr; /* alias of inet_rcv_saddr */
466#if IS_ENABLED(CONFIG_IPV6)
467 ipv6_addr_set_v4mapped(addr, &sk->sk_v6_rcv_saddr);
468#endif
469}
470
471int __inet_hash_connect(struct inet_timewait_death_row *death_row,
472 struct sock *sk, u64 port_offset,
473 int (*check_established)(struct inet_timewait_death_row *,
474 struct sock *, __u16,
475 struct inet_timewait_sock **));
476
477int inet_hash_connect(struct inet_timewait_death_row *death_row,
478 struct sock *sk);
479#endif /* _INET_HASHTABLES_H */