xref: /linux/include/net/inet6_hashtables.h (revision d140ad96146b6e7b196c31cbbb0f971845bfd053)
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 _INET6_HASHTABLES_H
15 #define _INET6_HASHTABLES_H
16 
17 
18 #if IS_ENABLED(CONFIG_IPV6)
19 #include <linux/in6.h>
20 #include <linux/ipv6.h>
21 #include <linux/types.h>
22 #include <linux/jhash.h>
23 
24 #include <net/inet_sock.h>
25 
26 #include <net/ipv6.h>
27 #include <net/netns/hash.h>
28 
29 struct inet_hashinfo;
30 
31 static inline unsigned int inet6_ehashfn(struct net *net,
32 				const struct in6_addr *laddr, const u16 lport,
33 				const struct in6_addr *faddr, const __be16 fport)
34 {
35 	u32 ports = (((u32)lport) << 16) | (__force u32)fport;
36 
37 	return jhash_3words((__force u32)laddr->s6_addr32[3],
38 			    ipv6_addr_jhash(faddr),
39 			    ports,
40 			    inet_ehash_secret + net_hash_mix(net));
41 }
42 
43 static inline int inet6_sk_ehashfn(const struct sock *sk)
44 {
45 	const struct inet_sock *inet = inet_sk(sk);
46 	const struct ipv6_pinfo *np = inet6_sk(sk);
47 	const struct in6_addr *laddr = &np->rcv_saddr;
48 	const struct in6_addr *faddr = &np->daddr;
49 	const __u16 lport = inet->inet_num;
50 	const __be16 fport = inet->inet_dport;
51 	struct net *net = sock_net(sk);
52 
53 	return inet6_ehashfn(net, laddr, lport, faddr, fport);
54 }
55 
56 int __inet6_hash(struct sock *sk, struct inet_timewait_sock *twp);
57 
58 /*
59  * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
60  * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
61  *
62  * The sockhash lock must be held as a reader here.
63  */
64 struct sock *__inet6_lookup_established(struct net *net,
65 					struct inet_hashinfo *hashinfo,
66 					const struct in6_addr *saddr,
67 					const __be16 sport,
68 					const struct in6_addr *daddr,
69 					const u16 hnum, const int dif);
70 
71 struct sock *inet6_lookup_listener(struct net *net,
72 				   struct inet_hashinfo *hashinfo,
73 				   const struct in6_addr *saddr,
74 				   const __be16 sport,
75 				   const struct in6_addr *daddr,
76 				   const unsigned short hnum, const int dif);
77 
78 static inline struct sock *__inet6_lookup(struct net *net,
79 					  struct inet_hashinfo *hashinfo,
80 					  const struct in6_addr *saddr,
81 					  const __be16 sport,
82 					  const struct in6_addr *daddr,
83 					  const u16 hnum,
84 					  const int dif)
85 {
86 	struct sock *sk = __inet6_lookup_established(net, hashinfo, saddr,
87 						sport, daddr, hnum, dif);
88 	if (sk)
89 		return sk;
90 
91 	return inet6_lookup_listener(net, hashinfo, saddr, sport,
92 				     daddr, hnum, dif);
93 }
94 
95 static inline struct sock *__inet6_lookup_skb(struct inet_hashinfo *hashinfo,
96 					      struct sk_buff *skb,
97 					      const __be16 sport,
98 					      const __be16 dport)
99 {
100 	struct sock *sk = skb_steal_sock(skb);
101 
102 	if (sk)
103 		return sk;
104 
105 	return __inet6_lookup(dev_net(skb_dst(skb)->dev), hashinfo,
106 			      &ipv6_hdr(skb)->saddr, sport,
107 			      &ipv6_hdr(skb)->daddr, ntohs(dport),
108 			      inet6_iif(skb));
109 }
110 
111 struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
112 			  const struct in6_addr *saddr, const __be16 sport,
113 			  const struct in6_addr *daddr, const __be16 dport,
114 			  const int dif);
115 #endif /* IS_ENABLED(CONFIG_IPV6) */
116 #endif /* _INET6_HASHTABLES_H */
117