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 defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
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 
28 struct inet_hashinfo;
29 
30 /* I have no idea if this is a good hash for v6 or not. -DaveM */
31 static inline unsigned int inet6_ehashfn(const struct in6_addr *laddr, const u16 lport,
32 				const struct in6_addr *faddr, const __be16 fport)
33 {
34 	u32 ports = (lport ^ (__force u16)fport);
35 
36 	return jhash_3words((__force u32)laddr->s6_addr32[3],
37 			    (__force u32)faddr->s6_addr32[3],
38 			    ports, inet_ehash_secret);
39 }
40 
41 static inline int inet6_sk_ehashfn(const struct sock *sk)
42 {
43 	const struct inet_sock *inet = inet_sk(sk);
44 	const struct ipv6_pinfo *np = inet6_sk(sk);
45 	const struct in6_addr *laddr = &np->rcv_saddr;
46 	const struct in6_addr *faddr = &np->daddr;
47 	const __u16 lport = inet->num;
48 	const __be16 fport = inet->dport;
49 	return inet6_ehashfn(laddr, lport, faddr, fport);
50 }
51 
52 extern void __inet6_hash(struct sock *sk);
53 
54 /*
55  * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
56  * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
57  *
58  * The sockhash lock must be held as a reader here.
59  */
60 extern struct sock *__inet6_lookup_established(struct net *net,
61 					   struct inet_hashinfo *hashinfo,
62 					   const struct in6_addr *saddr,
63 					   const __be16 sport,
64 					   const struct in6_addr *daddr,
65 					   const u16 hnum,
66 					   const int dif);
67 
68 extern struct sock *inet6_lookup_listener(struct net *net,
69 					  struct inet_hashinfo *hashinfo,
70 					  const struct in6_addr *daddr,
71 					  const unsigned short hnum,
72 					  const int dif);
73 
74 static inline struct sock *__inet6_lookup(struct net *net,
75 					  struct inet_hashinfo *hashinfo,
76 					  const struct in6_addr *saddr,
77 					  const __be16 sport,
78 					  const struct in6_addr *daddr,
79 					  const u16 hnum,
80 					  const int dif)
81 {
82 	struct sock *sk = __inet6_lookup_established(net, hashinfo, saddr,
83 						sport, daddr, hnum, dif);
84 	if (sk)
85 		return sk;
86 
87 	return inet6_lookup_listener(net, hashinfo, daddr, hnum, dif);
88 }
89 
90 extern struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
91 				 const struct in6_addr *saddr, const __be16 sport,
92 				 const struct in6_addr *daddr, const __be16 dport,
93 				 const int dif);
94 #endif /* defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) */
95 #endif /* _INET6_HASHTABLES_H */
96