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 /*
42  * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
43  * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
44  *
45  * The sockhash lock must be held as a reader here.
46  */
47 struct sock *__inet6_lookup_established(struct net *net,
48 					struct inet_hashinfo *hashinfo,
49 					const struct in6_addr *saddr,
50 					const __be16 sport,
51 					const struct in6_addr *daddr,
52 					const u16 hnum, const int dif);
53 
54 struct sock *inet6_lookup_listener(struct net *net,
55 				   struct inet_hashinfo *hashinfo,
56 				   struct sk_buff *skb, int doff,
57 				   const struct in6_addr *saddr,
58 				   const __be16 sport,
59 				   const struct in6_addr *daddr,
60 				   const unsigned short hnum, const int dif);
61 
62 static inline struct sock *__inet6_lookup(struct net *net,
63 					  struct inet_hashinfo *hashinfo,
64 					  struct sk_buff *skb, int doff,
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 					  bool *refcounted)
71 {
72 	struct sock *sk = __inet6_lookup_established(net, hashinfo, saddr,
73 						sport, daddr, hnum, dif);
74 	*refcounted = true;
75 	if (sk)
76 		return sk;
77 	*refcounted = false;
78 	return inet6_lookup_listener(net, hashinfo, skb, doff, saddr, sport,
79 				     daddr, hnum, dif);
80 }
81 
82 static inline struct sock *__inet6_lookup_skb(struct inet_hashinfo *hashinfo,
83 					      struct sk_buff *skb, int doff,
84 					      const __be16 sport,
85 					      const __be16 dport,
86 					      int iif,
87 					      bool *refcounted)
88 {
89 	struct sock *sk = skb_steal_sock(skb);
90 
91 	*refcounted = true;
92 	if (sk)
93 		return sk;
94 
95 	return __inet6_lookup(dev_net(skb_dst(skb)->dev), hashinfo, skb,
96 			      doff, &ipv6_hdr(skb)->saddr, sport,
97 			      &ipv6_hdr(skb)->daddr, ntohs(dport),
98 			      iif, refcounted);
99 }
100 
101 struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
102 			  struct sk_buff *skb, int doff,
103 			  const struct in6_addr *saddr, const __be16 sport,
104 			  const struct in6_addr *daddr, const __be16 dport,
105 			  const int dif);
106 
107 int inet6_hash(struct sock *sk);
108 #endif /* IS_ENABLED(CONFIG_IPV6) */
109 
110 #define INET6_MATCH(__sk, __net, __saddr, __daddr, __ports, __dif)	\
111 	(((__sk)->sk_portpair == (__ports))			&&	\
112 	 ((__sk)->sk_family == AF_INET6)			&&	\
113 	 ipv6_addr_equal(&(__sk)->sk_v6_daddr, (__saddr))		&&	\
114 	 ipv6_addr_equal(&(__sk)->sk_v6_rcv_saddr, (__daddr))	&&	\
115 	 (!(__sk)->sk_bound_dev_if	||				\
116 	   ((__sk)->sk_bound_dev_if == (__dif))) 		&&	\
117 	 net_eq(sock_net(__sk), (__net)))
118 
119 #endif /* _INET6_HASHTABLES_H */
120