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(const u32 lhash,
32 				    const u16 lport,
33 				    const u32 fhash,
34 				    const __be16 fport,
35 				    const u32 initval)
36 {
37 	const u32 ports = (((u32)lport) << 16) | (__force u32)fport;
38 	return jhash_3words(lhash, fhash, ports, initval);
39 }
40 
41 int __inet6_hash(struct sock *sk, struct inet_timewait_sock *twp);
42 
43 /*
44  * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
45  * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
46  *
47  * The sockhash lock must be held as a reader here.
48  */
49 struct sock *__inet6_lookup_established(struct net *net,
50 					struct inet_hashinfo *hashinfo,
51 					const struct in6_addr *saddr,
52 					const __be16 sport,
53 					const struct in6_addr *daddr,
54 					const u16 hnum, const int dif);
55 
56 struct sock *inet6_lookup_listener(struct net *net,
57 				   struct inet_hashinfo *hashinfo,
58 				   const struct in6_addr *saddr,
59 				   const __be16 sport,
60 				   const struct in6_addr *daddr,
61 				   const unsigned short hnum, const int dif);
62 
63 static inline struct sock *__inet6_lookup(struct net *net,
64 					  struct inet_hashinfo *hashinfo,
65 					  const struct in6_addr *saddr,
66 					  const __be16 sport,
67 					  const struct in6_addr *daddr,
68 					  const u16 hnum,
69 					  const int dif)
70 {
71 	struct sock *sk = __inet6_lookup_established(net, hashinfo, saddr,
72 						sport, daddr, hnum, dif);
73 	if (sk)
74 		return sk;
75 
76 	return inet6_lookup_listener(net, hashinfo, saddr, sport,
77 				     daddr, hnum, dif);
78 }
79 
80 static inline struct sock *__inet6_lookup_skb(struct inet_hashinfo *hashinfo,
81 					      struct sk_buff *skb,
82 					      const __be16 sport,
83 					      const __be16 dport)
84 {
85 	struct sock *sk = skb_steal_sock(skb);
86 
87 	if (sk)
88 		return sk;
89 
90 	return __inet6_lookup(dev_net(skb_dst(skb)->dev), hashinfo,
91 			      &ipv6_hdr(skb)->saddr, sport,
92 			      &ipv6_hdr(skb)->daddr, ntohs(dport),
93 			      inet6_iif(skb));
94 }
95 
96 struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
97 			  const struct in6_addr *saddr, const __be16 sport,
98 			  const struct in6_addr *daddr, const __be16 dport,
99 			  const int dif);
100 #endif /* IS_ENABLED(CONFIG_IPV6) */
101 #endif /* _INET6_HASHTABLES_H */
102