include/net/inet6_hashtables.h

   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 typedef u32 (inet6_ehashfn_t)(const struct net *net,
  52                                const struct in6_addr *laddr, const u16 lport,
  53                                const struct in6_addr *faddr, const __be16 fport);
  54
  55 inet6_ehashfn_t inet6_ehashfn;
  56
  57 INDIRECT_CALLABLE_DECLARE(inet6_ehashfn_t udp6_ehashfn);
  58
  59 struct sock *inet6_lookup_reuseport(struct net *net, struct sock *sk,
  60                                     struct sk_buff *skb, int doff,
  61                                     const struct in6_addr *saddr,
  62                                     __be16 sport,
  63                                     const struct in6_addr *daddr,
  64                                     unsigned short hnum,
  65                                     inet6_ehashfn_t *ehashfn);
  66
  67 struct sock *inet6_lookup_listener(struct net *net,
  68                                    struct inet_hashinfo *hashinfo,
  69                                    struct sk_buff *skb, int doff,
  70                                    const struct in6_addr *saddr,
  71                                    const __be16 sport,
  72                                    const struct in6_addr *daddr,
  73                                    const unsigned short hnum,
  74                                    const int dif, const int sdif);
  75
  76 static inline struct sock *__inet6_lookup(struct net *net,
  77                                           struct inet_hashinfo *hashinfo,
  78                                           struct sk_buff *skb, int doff,
  79                                           const struct in6_addr *saddr,
  80                                           const __be16 sport,
  81                                           const struct in6_addr *daddr,
  82                                           const u16 hnum,
  83                                           const int dif, const int sdif,
  84                                           bool *refcounted)
  85 {
  86         struct sock *sk = __inet6_lookup_established(net, hashinfo, saddr,
  87                                                      sport, daddr, hnum,
  88                                                      dif, sdif);
  89         *refcounted = true;
  90         if (sk)
  91                 return sk;
  92         *refcounted = false;
  93         return inet6_lookup_listener(net, hashinfo, skb, doff, saddr, sport,
  94                                      daddr, hnum, dif, sdif);
  95 }
  96
  97 static inline struct sock *__inet6_lookup_skb(struct inet_hashinfo *hashinfo,
  98                                               struct sk_buff *skb, int doff,
  99                                               const __be16 sport,
 100                                               const __be16 dport,
 101                                               int iif, int sdif,
 102                                               bool *refcounted)
 103 {
 104         struct sock *sk = skb_steal_sock(skb, refcounted);
 105
 106         if (sk)
 107                 return sk;
 108
 109         return __inet6_lookup(dev_net(skb_dst(skb)->dev), hashinfo, skb,
 110                               doff, &ipv6_hdr(skb)->saddr, sport,
 111                               &ipv6_hdr(skb)->daddr, ntohs(dport),
 112                               iif, sdif, refcounted);
 113 }
 114
 115 struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
 116                           struct sk_buff *skb, int doff,
 117                           const struct in6_addr *saddr, const __be16 sport,
 118                           const struct in6_addr *daddr, const __be16 dport,
 119                           const int dif);
 120
 121 int inet6_hash(struct sock *sk);
 122
 123 static inline bool inet6_match(struct net *net, const struct sock *sk,
 124                                const struct in6_addr *saddr,
 125                                const struct in6_addr *daddr,
 126                                const __portpair ports,
 127                                const int dif, const int sdif)
 128 {
 129         if (!net_eq(sock_net(sk), net) ||
 130             sk->sk_family != AF_INET6 ||
 131             sk->sk_portpair != ports ||
 132             !ipv6_addr_equal(&sk->sk_v6_daddr, saddr) ||
 133             !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
 134                 return false;
 135
 136         /* READ_ONCE() paired with WRITE_ONCE() in sock_bindtoindex_locked() */
 137         return inet_sk_bound_dev_eq(net, READ_ONCE(sk->sk_bound_dev_if), dif,
 138                                     sdif);
 139 }
 140 #endif /* IS_ENABLED(CONFIG_IPV6) */
 141
 142 #endif /* _INET6_HASHTABLES_H */