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 _INET6_HASHTABLES_H
11#define _INET6_HASHTABLES_H
12
13
14#if IS_ENABLED(CONFIG_IPV6)
15#include <linux/in6.h>
16#include <linux/ipv6.h>
17#include <linux/types.h>
18#include <linux/jhash.h>
19
20#include <net/inet_sock.h>
21
22#include <net/ipv6.h>
23#include <net/netns/hash.h>
24
25struct inet_hashinfo;
26
27static inline unsigned int __inet6_ehashfn(const u32 lhash,
28				    const u16 lport,
29				    const u32 fhash,
30				    const __be16 fport,
31				    const u32 initval)
32{
33	const u32 ports = (((u32)lport) << 16) | (__force u32)fport;
34	return jhash_3words(lhash, fhash, ports, initval);
35}
36
37/*
38 * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
39 * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
40 *
41 * The sockhash lock must be held as a reader here.
42 */
43struct sock *__inet6_lookup_established(struct net *net,
44					struct inet_hashinfo *hashinfo,
45					const struct in6_addr *saddr,
46					const __be16 sport,
47					const struct in6_addr *daddr,
48					const u16 hnum, const int dif,
49					const int sdif);
50
51struct sock *inet6_lookup_listener(struct net *net,
52				   struct inet_hashinfo *hashinfo,
53				   struct sk_buff *skb, int doff,
54				   const struct in6_addr *saddr,
55				   const __be16 sport,
56				   const struct in6_addr *daddr,
57				   const unsigned short hnum,
58				   const int dif, const int sdif);
59
60static inline struct sock *__inet6_lookup(struct net *net,
61					  struct inet_hashinfo *hashinfo,
62					  struct sk_buff *skb, int doff,
63					  const struct in6_addr *saddr,
64					  const __be16 sport,
65					  const struct in6_addr *daddr,
66					  const u16 hnum,
67					  const int dif, const int sdif,
68					  bool *refcounted)
69{
70	struct sock *sk = __inet6_lookup_established(net, hashinfo, saddr,
71						     sport, daddr, hnum,
72						     dif, sdif);
73	*refcounted = true;
74	if (sk)
75		return sk;
76	*refcounted = false;
77	return inet6_lookup_listener(net, hashinfo, skb, doff, saddr, sport,
78				     daddr, hnum, dif, sdif);
79}
80
81static inline struct sock *__inet6_lookup_skb(struct inet_hashinfo *hashinfo,
82					      struct sk_buff *skb, int doff,
83					      const __be16 sport,
84					      const __be16 dport,
85					      int iif, int sdif,
86					      bool *refcounted)
87{
88	struct sock *sk = skb_steal_sock(skb, refcounted);
89
90	if (sk)
91		return sk;
92
93	return __inet6_lookup(dev_net(skb_dst(skb)->dev), hashinfo, skb,
94			      doff, &ipv6_hdr(skb)->saddr, sport,
95			      &ipv6_hdr(skb)->daddr, ntohs(dport),
96			      iif, sdif, refcounted);
97}
98
99struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
100			  struct sk_buff *skb, int doff,
101			  const struct in6_addr *saddr, const __be16 sport,
102			  const struct in6_addr *daddr, const __be16 dport,
103			  const int dif);
104
105int inet6_hash(struct sock *sk);
106
107static inline bool inet6_match(struct net *net, const struct sock *sk,
108			       const struct in6_addr *saddr,
109			       const struct in6_addr *daddr,
110			       const __portpair ports,
111			       const int dif, const int sdif)
112{
113	if (!net_eq(sock_net(sk), net) ||
114	    sk->sk_family != AF_INET6 ||
115	    sk->sk_portpair != ports ||
116	    !ipv6_addr_equal(&sk->sk_v6_daddr, saddr) ||
117	    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
118		return false;
119
120	/* READ_ONCE() paired with WRITE_ONCE() in sock_bindtoindex_locked() */
121	return inet_sk_bound_dev_eq(net, READ_ONCE(sk->sk_bound_dev_if), dif,
122				    sdif);
123}
124#endif /* IS_ENABLED(CONFIG_IPV6) */
125
126#endif /* _INET6_HASHTABLES_H */
127