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 
25 struct inet_hashinfo;
26 
27 static 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  */
43 struct 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 
51 struct 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 
60 static 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 
81 static 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 
99 struct 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 
105 int inet6_hash(struct sock *sk);
106 
107 static 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 	int bound_dev_if;
114 
115 	if (!net_eq(sock_net(sk), net) ||
116 	    sk->sk_family != AF_INET6 ||
117 	    sk->sk_portpair != ports ||
118 	    !ipv6_addr_equal(&sk->sk_v6_daddr, saddr) ||
119 	    !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
120 		return false;
121 
122 	bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
123 	return bound_dev_if == dif || bound_dev_if == sdif;
124 }
125 #endif /* IS_ENABLED(CONFIG_IPV6) */
126 
127 #endif /* _INET6_HASHTABLES_H */
128