include/net/inet6_hashtables.h

0001 /* SPDX-License-Identifier: GPL-2.0-or-later */
0002 /*
0003  * INET     An implementation of the TCP/IP protocol suite for the LINUX
0004  *      operating system.  INET is implemented using the BSD Socket
0005  *      interface as the means of communication with the user level.
0006  *
0007  * Authors: Lotsa people, from code originally in tcp
0008  */
0009
0010 #ifndef _INET6_HASHTABLES_H
0011 #define _INET6_HASHTABLES_H
0012
0013
0014 #if IS_ENABLED(CONFIG_IPV6)
0015 #include <linux/in6.h>
0016 #include <linux/ipv6.h>
0017 #include <linux/types.h>
0018 #include <linux/jhash.h>
0019
0020 #include <net/inet_sock.h>
0021
0022 #include <net/ipv6.h>
0023 #include <net/netns/hash.h>
0024
0025 struct inet_hashinfo;
0026
0027 static inline unsigned int __inet6_ehashfn(const u32 lhash,
0028                     const u16 lport,
0029                     const u32 fhash,
0030                     const __be16 fport,
0031                     const u32 initval)
0032 {
0033     const u32 ports = (((u32)lport) << 16) | (__force u32)fport;
0034     return jhash_3words(lhash, fhash, ports, initval);
0035 }
0036
0037 /*
0038  * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
0039  * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
0040  *
0041  * The sockhash lock must be held as a reader here.
0042  */
0043 struct sock *__inet6_lookup_established(struct net *net,
0044                     struct inet_hashinfo *hashinfo,
0045                     const struct in6_addr *saddr,
0046                     const __be16 sport,
0047                     const struct in6_addr *daddr,
0048                     const u16 hnum, const int dif,
0049                     const int sdif);
0050
0051 struct sock *inet6_lookup_listener(struct net *net,
0052                    struct inet_hashinfo *hashinfo,
0053                    struct sk_buff *skb, int doff,
0054                    const struct in6_addr *saddr,
0055                    const __be16 sport,
0056                    const struct in6_addr *daddr,
0057                    const unsigned short hnum,
0058                    const int dif, const int sdif);
0059
0060 static inline struct sock *__inet6_lookup(struct net *net,
0061                       struct inet_hashinfo *hashinfo,
0062                       struct sk_buff *skb, int doff,
0063                       const struct in6_addr *saddr,
0064                       const __be16 sport,
0065                       const struct in6_addr *daddr,
0066                       const u16 hnum,
0067                       const int dif, const int sdif,
0068                       bool *refcounted)
0069 {
0070     struct sock *sk = __inet6_lookup_established(net, hashinfo, saddr,
0071                              sport, daddr, hnum,
0072                              dif, sdif);
0073     *refcounted = true;
0074     if (sk)
0075         return sk;
0076     *refcounted = false;
0077     return inet6_lookup_listener(net, hashinfo, skb, doff, saddr, sport,
0078                      daddr, hnum, dif, sdif);
0079 }
0080
0081 static inline struct sock *__inet6_lookup_skb(struct inet_hashinfo *hashinfo,
0082                           struct sk_buff *skb, int doff,
0083                           const __be16 sport,
0084                           const __be16 dport,
0085                           int iif, int sdif,
0086                           bool *refcounted)
0087 {
0088     struct sock *sk = skb_steal_sock(skb, refcounted);
0089
0090     if (sk)
0091         return sk;
0092
0093     return __inet6_lookup(dev_net(skb_dst(skb)->dev), hashinfo, skb,
0094                   doff, &ipv6_hdr(skb)->saddr, sport,
0095                   &ipv6_hdr(skb)->daddr, ntohs(dport),
0096                   iif, sdif, refcounted);
0097 }
0098
0099 struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
0100               struct sk_buff *skb, int doff,
0101               const struct in6_addr *saddr, const __be16 sport,
0102               const struct in6_addr *daddr, const __be16 dport,
0103               const int dif);
0104
0105 int inet6_hash(struct sock *sk);
0106
0107 static inline bool inet6_match(struct net *net, const struct sock *sk,
0108                    const struct in6_addr *saddr,
0109                    const struct in6_addr *daddr,
0110                    const __portpair ports,
0111                    const int dif, const int sdif)
0112 {
0113     if (!net_eq(sock_net(sk), net) ||
0114         sk->sk_family != AF_INET6 ||
0115         sk->sk_portpair != ports ||
0116         !ipv6_addr_equal(&sk->sk_v6_daddr, saddr) ||
0117         !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
0118         return false;
0119
0120     /* READ_ONCE() paired with WRITE_ONCE() in sock_bindtoindex_locked() */
0121     return inet_sk_bound_dev_eq(net, READ_ONCE(sk->sk_bound_dev_if), dif,
0122                     sdif);
0123 }
0124 #endif /* IS_ENABLED(CONFIG_IPV6) */
0125
0126 #endif /* _INET6_HASHTABLES_H */