*
* 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
*/
#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>
+
+void __inet6_hash(struct inet_hashinfo *hashinfo,
+ struct sock *sk)
+{
+ 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);
+ hash &= (hashinfo->ehash_size - 1);
+ list = &hashinfo->ehash[hash].chain;
+ lock = &hashinfo->ehash[hash].lock;
+ write_lock(lock);
+ }
+
+ __sk_add_node(sk, list);
+ sock_prot_inc_use(sk->sk_prot);
+ 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 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.
+ */
+ unsigned int hash = inet6_ehashfn(daddr, hnum, saddr, sport);
+ struct inet_ehash_bucket *head = inet_ehash_bucket(hashinfo, hash);
+
+ prefetch(head->chain.first);
+ 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, 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 + 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 inet6_timewait_sock *tw6 = inet6_twsk(sk);
+
+ if (ipv6_addr_equal(&tw6->tw_v6_daddr, saddr) &&
+ ipv6_addr_equal(&tw6->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;
+}
+EXPORT_SYMBOL(__inet6_lookup_established);
struct sock *inet6_lookup_listener(struct inet_hashinfo *hashinfo,
const struct in6_addr *daddr,
}
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 u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
+ const unsigned int hash = inet6_ehashfn(daddr, inet->num, saddr,
+ inet->dport);
+ struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
+ struct sock *sk2;
+ const struct hlist_node *node;
+ struct inet_timewait_sock *tw;
+
+ prefetch(head->chain.first);
+ write_lock(&head->lock);
+
+ /* Check TIME-WAIT sockets first. */
+ sk_for_each(sk2, node, &(head + hinfo->ehash_size)->chain) {
+ const struct inet6_timewait_sock *tw6 = inet6_twsk(sk2);
+
+ tw = inet_twsk(sk2);
+
+ if(*((__u32 *)&(tw->tw_dport)) == ports &&
+ sk2->sk_family == PF_INET6 &&
+ ipv6_addr_equal(&tw6->tw_v6_daddr, saddr) &&
+ ipv6_addr_equal(&tw6->tw_v6_rcv_saddr, daddr) &&
+ sk2->sk_bound_dev_if == sk->sk_bound_dev_if) {
+ 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, 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_inc_use(sk->sk_prot);
+ write_unlock(&head->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(&head->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)
+{
+ struct inet_hashinfo *hinfo = death_row->hashinfo;
+ const unsigned short snum = inet_sk(sk)->num;
+ struct inet_bind_hashbucket *head;
+ struct inet_bind_bucket *tb;
+ int ret;
+
+ if (snum == 0) {
+ const int low = sysctl_local_port_range[0];
+ const int high = sysctl_local_port_range[1];
+ const int range = high - low;
+ int i, port;
+ static u32 hint;
+ const u32 offset = hint + inet6_sk_port_offset(sk);
+ struct hlist_node *node;
+ struct inet_timewait_sock *tw = NULL;
+
+ local_bh_disable();
+ for (i = 1; i <= range; i++) {
+ port = low + (i + offset) % range;
+ head = &hinfo->bhash[inet_bhashfn(port, hinfo->bhash_size)];
+ spin_lock(&head->lock);
+
+ /* Does not bother with rcv_saddr checks,
+ * because the established check is already
+ * unique enough.
+ */
+ inet_bind_bucket_for_each(tb, node, &head->chain) {
+ if (tb->port == port) {
+ BUG_TRAP(!hlist_empty(&tb->owners));
+ if (tb->fastreuse >= 0)
+ goto next_port;
+ if (!__inet6_check_established(death_row,
+ sk, port,
+ &tw))
+ goto ok;
+ goto next_port;
+ }
+ }
+
+ tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
+ head, port);
+ if (!tb) {
+ spin_unlock(&head->lock);
+ break;
+ }
+ tb->fastreuse = -1;
+ goto ok;
+
+ next_port:
+ spin_unlock(&head->lock);
+ }
+ local_bh_enable();
+
+ return -EADDRNOTAVAIL;
+
+ok:
+ hint += i;
+
+ /* Head lock still held and bh's disabled */
+ inet_bind_hash(sk, tb, port);
+ if (sk_unhashed(sk)) {
+ inet_sk(sk)->sport = htons(port);
+ __inet6_hash(hinfo, sk);
+ }
+ spin_unlock(&head->lock);
+
+ if (tw) {
+ inet_twsk_deschedule(tw, death_row);
+ inet_twsk_put(tw);
+ }
+
+ ret = 0;
+ goto out;
+ }
+
+ head = &hinfo->bhash[inet_bhashfn(snum, hinfo->bhash_size)];
+ tb = inet_csk(sk)->icsk_bind_hash;
+ spin_lock_bh(&head->lock);
+
+ if (sk_head(&tb->owners) == sk && sk->sk_bind_node.next == NULL) {
+ __inet6_hash(hinfo, sk);
+ spin_unlock_bh(&head->lock);
+ return 0;
+ } else {
+ spin_unlock(&head->lock);
+ /* No definite answer... Walk to established hash table */
+ ret = __inet6_check_established(death_row, sk, snum, NULL);
+out:
+ local_bh_enable();
+ return ret;
+ }
+}
+
+EXPORT_SYMBOL_GPL(inet6_hash_connect);
projects / linux-2.6-omap-h63xx.git / blobdiff