diff options
Diffstat (limited to 'include/net/inet6_hashtables.h')
| -rw-r--r-- | include/net/inet6_hashtables.h | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/include/net/inet6_hashtables.h b/include/net/inet6_hashtables.h new file mode 100644 index 00000000000..03df3b15796 --- /dev/null +++ b/include/net/inet6_hashtables.h @@ -0,0 +1,130 @@ +/* + * 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 + +#include <linux/config.h> + +#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) +#include <linux/in6.h> +#include <linux/ipv6.h> +#include <linux/types.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 int inet6_ehashfn(const struct in6_addr *laddr, const u16 lport, + const struct in6_addr *faddr, const u16 fport, + const int ehash_size) +{ + int hashent = (lport ^ fport); + + hashent ^= (laddr->s6_addr32[3] ^ faddr->s6_addr32[3]); + hashent ^= hashent >> 16; + hashent ^= hashent >> 8; + return (hashent & (ehash_size - 1)); +} + +static inline int inet6_sk_ehashfn(const struct sock *sk, const int ehash_size) +{ + 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 __u16 fport = inet->dport; + return inet6_ehashfn(laddr, lport, faddr, fport, ehash_size); +} + +/* + * 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. + */ +static inline struct sock * + __inet6_lookup_established(struct inet_hashinfo *hashinfo, + const struct in6_addr *saddr, + const u16 sport, + const struct in6_addr *daddr, + const u16 hnum, + const int dif) +{ + struct sock *sk; + const struct hlist_node *node; + const __u32 ports = INET_COMBINED_PORTS(sport, hnum); + /* Optimize here for direct hit, only listening connections can + * have wildcards anyways. + */ + const int hash = inet6_ehashfn(daddr, hnum, saddr, sport, + hashinfo->ehash_size); + struct inet_ehash_bucket *head = &hashinfo->ehash[hash]; + + read_lock(&head->lock); + sk_for_each(sk, node, &head->chain) { + /* For IPV6 do the cheaper port and family tests first. */ + if (INET6_MATCH(sk, saddr, daddr, ports, dif)) + goto hit; /* You sunk my battleship! */ + } + /* Must check for a TIME_WAIT'er before going to listener hash. */ + sk_for_each(sk, node, &(head + hashinfo->ehash_size)->chain) { + const struct inet_timewait_sock *tw = inet_twsk(sk); + + if(*((__u32 *)&(tw->tw_dport)) == ports && + sk->sk_family == PF_INET6) { + const struct tcp6_timewait_sock *tcp6tw = tcp6_twsk(sk); + + if (ipv6_addr_equal(&tcp6tw->tw_v6_daddr, saddr) && + ipv6_addr_equal(&tcp6tw->tw_v6_rcv_saddr, daddr) && + (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)) + goto hit; + } + } + read_unlock(&head->lock); + return NULL; + +hit: + sock_hold(sk); + read_unlock(&head->lock); + return sk; +} + +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 u16 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 u16 sport, + const struct in6_addr *daddr, const u16 dport, + const int dif); +#endif /* defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) */ +#endif /* _INET6_HASHTABLES_H */ |