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Diffstat (limited to 'net/ipv6/inet6_hashtables.c')
-rw-r--r--net/ipv6/inet6_hashtables.c183
1 files changed, 181 insertions, 2 deletions
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index 01d5f46d4e40..4154f3a8b6cf 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -5,7 +5,8 @@
*
* 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
@@ -14,12 +15,13 @@
*/
#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,
@@ -79,3 +81,180 @@ struct sock *inet6_lookup(struct inet_hashinfo *hashinfo,
}
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;
+ const 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:
+ 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);