/*
* 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.
*
* Generic INET6 transport hashtables
*
* Authors: Lotsa people, from code originally in tcp, generalised here
* by Arnaldo Carvalho de Melo <acme@mandriva.com>
*
* 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.
*/
#include <linux/module.h>
#include <linux/random.h>
#include <net/inet_connection_sock.h>
#include <net/inet_hashtables.h>
#include <net/inet6_hashtables.h>
#include <net/ip.h>
void __inet6_hash(struct sock *sk)
{
struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
struct hlist_head *list;
rwlock_t *lock;
BUG_TRAP(sk_unhashed(sk));
if (sk->sk_state == TCP_LISTEN) {
list = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
lock = &hashinfo->lhash_lock;
inet_listen_wlock(hashinfo);
} else {
unsigned int hash;
sk->sk_hash = hash = inet6_sk_ehashfn(sk);
list = &inet_ehash_bucket(hashinfo, hash)->chain;
lock = inet_ehash_lockp(hashinfo, hash);
write_lock(lock);
}
__sk_add_node(sk, list);
sock_prot_inuse_add(sk->sk_prot, 1);
write_unlock(lock);
}
EXPORT_SYMBOL(__inet6_hash);
/*
* 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.
*/
struct sock *__inet6_lookup_established(struct net *net,
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;
const struct hlist_node *node;
const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
/* Optimize here for direct hit, only listening connections can
* have wildcards anyways.
*/
unsigned int hash = inet6_ehashfn(daddr, hnum, saddr, sport);
struct inet_ehash_bucket *head = inet_ehash_bucket(hashinfo, hash);
rwlock_t *lock = inet_ehash_lockp(hashinfo, hash);
prefetch(head->chain.first);
read_lock(lock);
sk_for_each(sk, node, &head->chain) {
/* For IPV6 do the cheaper port and family tests first. */
if (INET6_MATCH(sk, net, hash, 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->twchain) {
if (INET6_TW_MATCH(sk, net, hash, saddr, daddr, ports, dif))
goto hit;
}
read_unlock(lock);
return NULL;
hit:
sock_hold(sk);
read_unlock(lock);
return sk;
}
EXPORT_SYMBOL(__inet6_lookup_established);
struct sock *inet6_lookup_listener(struct net *net,
struct inet_hashinfo *hashinfo, const struct in6_addr *daddr,
const unsigned short hnum, const int dif)
{
struct sock *sk;
const struct hlist_node *node;
struct sock *result = NULL;
int score, hiscore = 0;
read_lock(&hashinfo->lhash_lock);
sk_for_each(sk, node, &hashinfo->listening_hash[inet_lhashfn(hnum)]) {
if (sk->sk_net == net && inet_sk(sk)->num == hnum &&
sk->sk_family == PF_INET6) {
const struct ipv6_pinfo *np = inet6_sk(sk);
score = 1;
if (!ipv6_addr_any(&np->rcv_saddr)) {
if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
continue;
score++;
}
if (sk->sk_bound_dev_if) {
if (sk->sk_bound_dev_if != dif)
continue;
score++;
}
if (score == 3) {
result = sk;
break;
}
if (score > hiscore) {
hiscore = score;
result = sk;
}
}
}
if (result)
sock_hold(result);
read_unlock(&hashinfo->lhash_lock);
return result;
}
EXPORT_SYMBOL_GPL(inet6_lookup_listener);
struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
const struct in6_addr *saddr, const __be16 sport,
const struct in6_addr *daddr, const __be16 dport,
const int dif)
{
struct sock *sk;
local_bh_disable();
sk = __inet6_lookup(net, hashinfo, saddr, sport, daddr, ntohs(dport), dif);
local_bh_enable();
return sk;
}
EXPORT_SYMBOL_GPL(inet6_lookup);
static int __inet6_check_established(struct inet_timewait_death_row *death_row,
struct sock *sk, const __u16 lport,
struct inet_timewait_sock **twp)
{
struct inet_hashinfo *hinfo = death_row->hashinfo;
struct inet_sock *inet = inet_sk(sk);
const struct ipv6_pinfo *np = inet6_sk(sk);
const struct in6_addr *daddr = &np->rcv_saddr;
const struct in6_addr *saddr = &np->daddr;
const int dif = sk->sk_bound_dev_if;
const __portpair ports = INET_COMBINED_PORTS(inet->dport, lport);
const unsigned int hash = inet6_ehashfn(daddr, lport, saddr,
inet->dport);
struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
rwlock_t *lock = inet_ehash_lockp(hinfo, hash);
struct sock *sk2;
const struct hlist_node *node;
struct inet_timewait_sock *tw;
struct net *net = sk->sk_net;
prefetch(head->chain.first);
write_lock(lock);
/* Check TIME-WAIT sockets first. */
sk_for_each(sk2, node, &head->twchain) {
tw = inet_twsk(sk2);
if (INET6_TW_MATCH(sk2, net, hash, saddr, daddr, ports, dif)) {
if (twsk_unique(sk, sk2, twp))
goto unique;
else
goto not_unique;
}
}
tw = NULL;
/* And established part... */
sk_for_each(sk2, node, &head->chain) {
if (INET6_MATCH(sk2, net, hash, saddr, daddr, ports, dif))
goto not_unique;
}
unique:
/* Must record num and sport now. Otherwise we will see
* in hash table socket with a funny identity. */
inet->num = lport;
inet->sport = htons(lport);
BUG_TRAP(sk_unhashed(sk));
__sk_add_node(sk, &head->chain);
sk->sk_hash = hash;
sock_prot_inuse_add(sk->sk_prot, 1);
write_unlock(lock);
if (twp != NULL) {
*twp = tw;
NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
} else if (tw != NULL) {
/* Silly. Should hash-dance instead... */
inet_twsk_deschedule(tw, death_row);
NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
inet_twsk_put(tw);
}
return 0;
not_unique:
write_unlock(lock);
return -EADDRNOTAVAIL;
}
static inline u32 inet6_sk_port_offset(const struct sock *sk)
{
const struct inet_sock *inet = inet_sk(sk);
const struct ipv6_pinfo *np = inet6_sk(sk);
return secure_ipv6_port_ephemeral(np->rcv_saddr.s6_addr32,
np->daddr.s6_addr32,
inet->dport);
}
int inet6_hash_connect(struct inet_timewait_death_row *death_row,
struct sock *sk)
{
return __inet_hash_connect(death_row, sk, inet6_sk_port_offset(sk),
__inet6_check_established, __inet6_hash);
}
EXPORT_SYMBOL_GPL(inet6_hash_connect);
