2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * Generic INET6 transport hashtables
8 * Authors: Lotsa people, from code originally in tcp, generalised here
9 * by Arnaldo Carvalho de Melo <acme@mandriva.com>
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
17 #include <linux/module.h>
18 #include <linux/random.h>
20 #include <net/inet_connection_sock.h>
21 #include <net/inet_hashtables.h>
22 #include <net/inet6_hashtables.h>
25 void __inet6_hash(struct sock *sk)
27 struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
29 WARN_ON(!sk_unhashed(sk));
31 if (sk->sk_state == TCP_LISTEN) {
32 struct inet_listen_hashbucket *ilb;
34 ilb = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
35 spin_lock(&ilb->lock);
36 __sk_add_node(sk, &ilb->head);
37 spin_unlock(&ilb->lock);
40 struct hlist_nulls_head *list;
43 sk->sk_hash = hash = inet6_sk_ehashfn(sk);
44 list = &inet_ehash_bucket(hashinfo, hash)->chain;
45 lock = inet_ehash_lockp(hashinfo, hash);
47 __sk_nulls_add_node_rcu(sk, list);
51 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
53 EXPORT_SYMBOL(__inet6_hash);
56 * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
57 * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
59 * The sockhash lock must be held as a reader here.
61 struct sock *__inet6_lookup_established(struct net *net,
62 struct inet_hashinfo *hashinfo,
63 const struct in6_addr *saddr,
65 const struct in6_addr *daddr,
70 const struct hlist_nulls_node *node;
71 const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
72 /* Optimize here for direct hit, only listening connections can
73 * have wildcards anyways.
75 unsigned int hash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
76 unsigned int slot = hash & (hashinfo->ehash_size - 1);
77 struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
82 sk_nulls_for_each_rcu(sk, node, &head->chain) {
83 /* For IPV6 do the cheaper port and family tests first. */
84 if (INET6_MATCH(sk, net, hash, saddr, daddr, ports, dif)) {
85 if (unlikely(!atomic_inc_not_zero(&sk->sk_refcnt)))
87 if (!INET6_MATCH(sk, net, hash, saddr, daddr, ports, dif)) {
94 if (get_nulls_value(node) != slot)
98 /* Must check for a TIME_WAIT'er before going to listener hash. */
99 sk_nulls_for_each_rcu(sk, node, &head->twchain) {
100 if (INET6_TW_MATCH(sk, net, hash, saddr, daddr, ports, dif)) {
101 if (unlikely(!atomic_inc_not_zero(&sk->sk_refcnt))) {
105 if (!INET6_TW_MATCH(sk, net, hash, saddr, daddr, ports, dif)) {
112 if (get_nulls_value(node) != slot)
119 EXPORT_SYMBOL(__inet6_lookup_established);
121 struct sock *inet6_lookup_listener(struct net *net,
122 struct inet_hashinfo *hashinfo, const struct in6_addr *daddr,
123 const unsigned short hnum, const int dif)
126 const struct hlist_node *node;
127 struct sock *result = NULL;
128 int score, hiscore = 0;
129 struct inet_listen_hashbucket *ilb;
131 ilb = &hashinfo->listening_hash[inet_lhashfn(net, hnum)];
132 spin_lock(&ilb->lock);
133 sk_for_each(sk, node, &ilb->head) {
134 if (net_eq(sock_net(sk), net) && inet_sk(sk)->num == hnum &&
135 sk->sk_family == PF_INET6) {
136 const struct ipv6_pinfo *np = inet6_sk(sk);
139 if (!ipv6_addr_any(&np->rcv_saddr)) {
140 if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
144 if (sk->sk_bound_dev_if) {
145 if (sk->sk_bound_dev_if != dif)
153 if (score > hiscore) {
161 spin_unlock(&ilb->lock);
165 EXPORT_SYMBOL_GPL(inet6_lookup_listener);
167 struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
168 const struct in6_addr *saddr, const __be16 sport,
169 const struct in6_addr *daddr, const __be16 dport,
175 sk = __inet6_lookup(net, hashinfo, saddr, sport, daddr, ntohs(dport), dif);
181 EXPORT_SYMBOL_GPL(inet6_lookup);
183 static int __inet6_check_established(struct inet_timewait_death_row *death_row,
184 struct sock *sk, const __u16 lport,
185 struct inet_timewait_sock **twp)
187 struct inet_hashinfo *hinfo = death_row->hashinfo;
188 struct inet_sock *inet = inet_sk(sk);
189 const struct ipv6_pinfo *np = inet6_sk(sk);
190 const struct in6_addr *daddr = &np->rcv_saddr;
191 const struct in6_addr *saddr = &np->daddr;
192 const int dif = sk->sk_bound_dev_if;
193 const __portpair ports = INET_COMBINED_PORTS(inet->dport, lport);
194 struct net *net = sock_net(sk);
195 const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr,
197 struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
198 spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
200 const struct hlist_nulls_node *node;
201 struct inet_timewait_sock *tw;
205 /* Check TIME-WAIT sockets first. */
206 sk_nulls_for_each(sk2, node, &head->twchain) {
209 if (INET6_TW_MATCH(sk2, net, hash, saddr, daddr, ports, dif)) {
210 if (twsk_unique(sk, sk2, twp))
218 /* And established part... */
219 sk_nulls_for_each(sk2, node, &head->chain) {
220 if (INET6_MATCH(sk2, net, hash, saddr, daddr, ports, dif))
225 /* Must record num and sport now. Otherwise we will see
226 * in hash table socket with a funny identity. */
228 inet->sport = htons(lport);
229 WARN_ON(!sk_unhashed(sk));
230 __sk_nulls_add_node_rcu(sk, &head->chain);
233 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
237 NET_INC_STATS_BH(twsk_net(tw), LINUX_MIB_TIMEWAITRECYCLED);
238 } else if (tw != NULL) {
239 /* Silly. Should hash-dance instead... */
240 inet_twsk_deschedule(tw, death_row);
241 NET_INC_STATS_BH(twsk_net(tw), LINUX_MIB_TIMEWAITRECYCLED);
249 return -EADDRNOTAVAIL;
252 static inline u32 inet6_sk_port_offset(const struct sock *sk)
254 const struct inet_sock *inet = inet_sk(sk);
255 const struct ipv6_pinfo *np = inet6_sk(sk);
256 return secure_ipv6_port_ephemeral(np->rcv_saddr.s6_addr32,
261 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
264 return __inet_hash_connect(death_row, sk, inet6_sk_port_offset(sk),
265 __inet6_check_established, __inet6_hash);
268 EXPORT_SYMBOL_GPL(inet6_hash_connect);