*
* Generic INET6 transport hashtables
*
- * Authors: Lotsa people, from code originally in tcp
+ * 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
* 2 of the License, or (at your option) any later version.
*/
-#include <linux/config.h>
-
#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>
-struct sock *inet6_lookup_listener(struct inet_hashinfo *hashinfo,
- const struct in6_addr *daddr,
- const unsigned short hnum, const int dif)
+void __inet6_hash(struct sock *sk)
+{
+ struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
+
+ WARN_ON(!sk_unhashed(sk));
+
+ if (sk->sk_state == TCP_LISTEN) {
+ struct inet_listen_hashbucket *ilb;
+
+ ilb = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
+ spin_lock(&ilb->lock);
+ __sk_nulls_add_node_rcu(sk, &ilb->head);
+ spin_unlock(&ilb->lock);
+ } else {
+ unsigned int hash;
+ struct hlist_nulls_head *list;
+ spinlock_t *lock;
+
+ sk->sk_hash = hash = inet6_sk_ehashfn(sk);
+ list = &inet_ehash_bucket(hashinfo, hash)->chain;
+ lock = inet_ehash_lockp(hashinfo, hash);
+ spin_lock(lock);
+ __sk_nulls_add_node_rcu(sk, list);
+ spin_unlock(lock);
+ }
+
+ sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
+}
+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;
- 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 (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++;
+ const struct hlist_nulls_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(net, daddr, hnum, saddr, sport);
+ unsigned int slot = hash & hashinfo->ehash_mask;
+ struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
+
+
+ rcu_read_lock();
+begin:
+ sk_nulls_for_each_rcu(sk, node, &head->chain) {
+ /* For IPV6 do the cheaper port and family tests first. */
+ if (INET6_MATCH(sk, net, hash, saddr, daddr, ports, dif)) {
+ if (unlikely(!atomic_inc_not_zero(&sk->sk_refcnt)))
+ goto begintw;
+ if (!INET6_MATCH(sk, net, hash, saddr, daddr, ports, dif)) {
+ sock_put(sk);
+ goto begin;
}
- if (score == 3) {
- result = sk;
- break;
+ goto out;
+ }
+ }
+ if (get_nulls_value(node) != slot)
+ goto begin;
+
+begintw:
+ /* Must check for a TIME_WAIT'er before going to listener hash. */
+ sk_nulls_for_each_rcu(sk, node, &head->twchain) {
+ if (INET6_TW_MATCH(sk, net, hash, saddr, daddr, ports, dif)) {
+ if (unlikely(!atomic_inc_not_zero(&sk->sk_refcnt))) {
+ sk = NULL;
+ goto out;
}
- if (score > hiscore) {
- hiscore = score;
- result = sk;
+ if (!INET6_TW_MATCH(sk, net, hash, saddr, daddr, ports, dif)) {
+ sock_put(sk);
+ goto begintw;
}
+ goto out;
}
}
- if (result)
- sock_hold(result);
- read_unlock(&hashinfo->lhash_lock);
+ if (get_nulls_value(node) != slot)
+ goto begintw;
+ sk = NULL;
+out:
+ rcu_read_unlock();
+ return sk;
+}
+EXPORT_SYMBOL(__inet6_lookup_established);
+
+static int inline compute_score(struct sock *sk, struct net *net,
+ const unsigned short hnum,
+ const struct in6_addr *daddr,
+ const int dif)
+{
+ int score = -1;
+
+ if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_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))
+ return -1;
+ score++;
+ }
+ if (sk->sk_bound_dev_if) {
+ if (sk->sk_bound_dev_if != dif)
+ return -1;
+ score++;
+ }
+ }
+ return score;
+}
+
+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_nulls_node *node;
+ struct sock *result;
+ int score, hiscore;
+ unsigned int hash = inet_lhashfn(net, hnum);
+ struct inet_listen_hashbucket *ilb = &hashinfo->listening_hash[hash];
+
+ rcu_read_lock();
+begin:
+ result = NULL;
+ hiscore = -1;
+ sk_nulls_for_each(sk, node, &ilb->head) {
+ score = compute_score(sk, net, hnum, daddr, dif);
+ if (score > hiscore) {
+ hiscore = score;
+ result = sk;
+ }
+ }
+ /*
+ * if the nulls value we got at the end of this lookup is
+ * not the expected one, we must restart lookup.
+ * We probably met an item that was moved to another chain.
+ */
+ if (get_nulls_value(node) != hash + LISTENING_NULLS_BASE)
+ goto begin;
+ if (result) {
+ if (unlikely(!atomic_inc_not_zero(&result->sk_refcnt)))
+ result = NULL;
+ else if (unlikely(compute_score(result, net, hnum, daddr,
+ dif) < hiscore)) {
+ sock_put(result);
+ goto begin;
+ }
+ }
+ rcu_read_unlock();
return result;
}
EXPORT_SYMBOL_GPL(inet6_lookup_listener);
-struct sock *inet6_lookup(struct inet_hashinfo *hashinfo,
- const struct in6_addr *saddr, const u16 sport,
- const struct in6_addr *daddr, const u16 dport,
+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(hashinfo, saddr, sport, daddr, ntohs(dport), dif);
+ 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->inet_dport, lport);
+ struct net *net = sock_net(sk);
+ const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr,
+ inet->inet_dport);
+ struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
+ spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
+ struct sock *sk2;
+ const struct hlist_nulls_node *node;
+ struct inet_timewait_sock *tw;
+
+ spin_lock(lock);
+
+ /* Check TIME-WAIT sockets first. */
+ sk_nulls_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_nulls_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->inet_num = lport;
+ inet->inet_sport = htons(lport);
+ WARN_ON(!sk_unhashed(sk));
+ __sk_nulls_add_node_rcu(sk, &head->chain);
+ sk->sk_hash = hash;
+ spin_unlock(lock);
+ sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
+
+ if (twp != NULL) {
+ *twp = tw;
+ NET_INC_STATS_BH(net, LINUX_MIB_TIMEWAITRECYCLED);
+ } else if (tw != NULL) {
+ /* Silly. Should hash-dance instead... */
+ inet_twsk_deschedule(tw, death_row);
+ NET_INC_STATS_BH(net, LINUX_MIB_TIMEWAITRECYCLED);
+
+ inet_twsk_put(tw);
+ }
+ return 0;
+
+not_unique:
+ spin_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->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);