[INET]: Generalise tcp_v4_hash_connect
Renaming it to inet_hash_connect, making it possible to ditch
dccp_v4_hash_connect and share the same code with TCP instead.
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index e8d29fe..3322811 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -15,12 +15,14 @@
#include <linux/config.h>
#include <linux/module.h>
+#include <linux/random.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <net/inet_connection_sock.h>
#include <net/inet_hashtables.h>
+#include <net/ip.h>
/*
* Allocate and initialize a new local port bind bucket.
@@ -163,3 +165,179 @@
}
EXPORT_SYMBOL_GPL(__inet_lookup_listener);
+
+/* called with local bh disabled */
+static int __inet_check_established(struct inet_timewait_death_row *death_row,
+ struct sock *sk, __u16 lport,
+ struct inet_timewait_sock **twp)
+{
+ struct inet_hashinfo *hinfo = death_row->hashinfo;
+ struct inet_sock *inet = inet_sk(sk);
+ u32 daddr = inet->rcv_saddr;
+ u32 saddr = inet->daddr;
+ int dif = sk->sk_bound_dev_if;
+ INET_ADDR_COOKIE(acookie, saddr, daddr)
+ const __u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
+ unsigned int hash = inet_ehashfn(daddr, lport, 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) {
+ tw = inet_twsk(sk2);
+
+ if (INET_TW_MATCH(sk2, hash, acookie, 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 (INET_MATCH(sk2, hash, acookie, 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);
+ sk->sk_hash = hash;
+ BUG_TRAP(sk_unhashed(sk));
+ __sk_add_node(sk, &head->chain);
+ sock_prot_inc_use(sk->sk_prot);
+ write_unlock(&head->lock);
+
+ if (twp) {
+ *twp = tw;
+ NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
+ } else if (tw) {
+ /* 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 inet_sk_port_offset(const struct sock *sk)
+{
+ const struct inet_sock *inet = inet_sk(sk);
+ return secure_ipv4_port_ephemeral(inet->rcv_saddr, inet->daddr,
+ inet->dport);
+}
+
+/*
+ * Bind a port for a connect operation and hash it.
+ */
+int inet_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) {
+ int low = sysctl_local_port_range[0];
+ int high = sysctl_local_port_range[1];
+ int range = high - low;
+ int i;
+ int port;
+ static u32 hint;
+ u32 offset = hint + inet_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 (!__inet_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);
+ __inet_hash(hinfo, sk, 0);
+ }
+ 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) {
+ __inet_hash(hinfo, sk, 0);
+ spin_unlock_bh(&head->lock);
+ return 0;
+ } else {
+ spin_unlock(&head->lock);
+ /* No definite answer... Walk to established hash table */
+ ret = __inet_check_established(death_row, sk, snum, NULL);
+out:
+ local_bh_enable();
+ return ret;
+ }
+}
+
+EXPORT_SYMBOL_GPL(inet_hash_connect);