kernel-ark/include/net/inet6_hashtables.h
David S. Miller b3da2cf37c [INET]: Use jhash + random secret for ehash.
The days are gone when this was not an issue, there are folks out
there with huge bot networks that can be used to attack the
established hash tables on remote systems.

So just like the routing cache and connection tracking
hash, use Jenkins hash with random secret input.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:28:06 -07:00

93 lines
2.9 KiB
C

/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* Authors: Lotsa people, from code originally in tcp
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _INET6_HASHTABLES_H
#define _INET6_HASHTABLES_H
#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
#include <linux/in6.h>
#include <linux/ipv6.h>
#include <linux/types.h>
#include <linux/jhash.h>
#include <net/inet_sock.h>
#include <net/ipv6.h>
struct inet_hashinfo;
/* I have no idea if this is a good hash for v6 or not. -DaveM */
static inline unsigned int inet6_ehashfn(const struct in6_addr *laddr, const u16 lport,
const struct in6_addr *faddr, const __be16 fport)
{
u32 ports = (lport ^ (__force u16)fport);
return jhash_3words((__force u32)laddr->s6_addr32[3],
(__force u32)faddr->s6_addr32[3],
ports, inet_ehash_secret);
}
static inline int inet6_sk_ehashfn(const struct sock *sk)
{
const struct inet_sock *inet = inet_sk(sk);
const struct ipv6_pinfo *np = inet6_sk(sk);
const struct in6_addr *laddr = &np->rcv_saddr;
const struct in6_addr *faddr = &np->daddr;
const __u16 lport = inet->num;
const __be16 fport = inet->dport;
return inet6_ehashfn(laddr, lport, faddr, fport);
}
extern void __inet6_hash(struct inet_hashinfo *hashinfo, struct sock *sk);
/*
* Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
* we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
*
* The sockhash lock must be held as a reader here.
*/
extern struct sock *__inet6_lookup_established(struct inet_hashinfo *hashinfo,
const struct in6_addr *saddr,
const __be16 sport,
const struct in6_addr *daddr,
const u16 hnum,
const int dif);
extern struct sock *inet6_lookup_listener(struct inet_hashinfo *hashinfo,
const struct in6_addr *daddr,
const unsigned short hnum,
const int dif);
static inline struct sock *__inet6_lookup(struct inet_hashinfo *hashinfo,
const struct in6_addr *saddr,
const __be16 sport,
const struct in6_addr *daddr,
const u16 hnum,
const int dif)
{
struct sock *sk = __inet6_lookup_established(hashinfo, saddr, sport,
daddr, hnum, dif);
if (sk)
return sk;
return inet6_lookup_listener(hashinfo, daddr, hnum, dif);
}
extern struct sock *inet6_lookup(struct inet_hashinfo *hashinfo,
const struct in6_addr *saddr, const __be16 sport,
const struct in6_addr *daddr, const __be16 dport,
const int dif);
#endif /* defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) */
#endif /* _INET6_HASHTABLES_H */