include/net/inet6_hashtables.h

   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 #include <linux/config.h>
  18
  19 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
  20 #include <linux/in6.h>
  21 #include <linux/ipv6.h>
  22 #include <linux/types.h>
  23
  24 #include <net/ipv6.h>
  25
  26 struct inet_hashinfo;
  27
  28 /* I have no idea if this is a good hash for v6 or not. -DaveM */
  29 static inline unsigned int inet6_ehashfn(const struct in6_addr *laddr, const u16 lport,
  30                                 const struct in6_addr *faddr, const u16 fport)
  31 {
  32         unsigned int hashent = (lport ^ fport);
  33
  34         hashent ^= (laddr->s6_addr32[3] ^ faddr->s6_addr32[3]);
  35         hashent ^= hashent >> 16;
  36         hashent ^= hashent >> 8;
  37         return hashent;
  38 }
  39
  40 static inline int inet6_sk_ehashfn(const struct sock *sk)
  41 {
  42         const struct inet_sock *inet = inet_sk(sk);
  43         const struct ipv6_pinfo *np = inet6_sk(sk);
  44         const struct in6_addr *laddr = &np->rcv_saddr;
  45         const struct in6_addr *faddr = &np->daddr;
  46         const __u16 lport = inet->num;
  47         const __u16 fport = inet->dport;
  48         return inet6_ehashfn(laddr, lport, faddr, fport);
  49 }
  50
  51 extern void __inet6_hash(struct inet_hashinfo *hashinfo, struct sock *sk);
  52
  53 /*
  54  * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
  55  * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
  56  *
  57  * The sockhash lock must be held as a reader here.
  58  */
  59 extern struct sock *__inet6_lookup_established(struct inet_hashinfo *hashinfo,
  60                                            const struct in6_addr *saddr,
  61                                            const u16 sport,
  62                                            const struct in6_addr *daddr,
  63                                            const u16 hnum,
  64                                            const int dif);
  65
  66 extern struct sock *inet6_lookup_listener(struct inet_hashinfo *hashinfo,
  67                                           const struct in6_addr *daddr,
  68                                           const unsigned short hnum,
  69                                           const int dif);
  70
  71 static inline struct sock *__inet6_lookup(struct inet_hashinfo *hashinfo,
  72                                           const struct in6_addr *saddr,
  73                                           const u16 sport,
  74                                           const struct in6_addr *daddr,
  75                                           const u16 hnum,
  76                                           const int dif)
  77 {
  78         struct sock *sk = __inet6_lookup_established(hashinfo, saddr, sport,
  79                                                      daddr, hnum, dif);
  80         if (sk)
  81                 return sk;
  82
  83         return inet6_lookup_listener(hashinfo, daddr, hnum, dif);
  84 }
  85
  86 extern struct sock *inet6_lookup(struct inet_hashinfo *hashinfo,
  87                                  const struct in6_addr *saddr, const u16 sport,
  88                                  const struct in6_addr *daddr, const u16 dport,
  89                                  const int dif);
  90 #endif /* defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) */
  91 #endif /* _INET6_HASHTABLES_H */