[linux-block.git] / net / ipv6 / inet6_hashtables.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		Generic INET6 transport hashtables
 *
 * Authors:	Lotsa people, from code originally in tcp, generalised here
 *		by Arnaldo Carvalho de Melo <acme@mandriva.com>
 */

#include <linux/module.h>
#include <linux/random.h>

#include <net/addrconf.h>
#include <net/inet_connection_sock.h>
#include <net/inet_hashtables.h>
#include <net/inet6_hashtables.h>
#include <net/secure_seq.h>
#include <net/ip.h>
#include <net/sock_reuseport.h>

extern struct inet_hashinfo tcp_hashinfo;

u32 inet6_ehashfn(const struct net *net,
		  const struct in6_addr *laddr, const u16 lport,
		  const struct in6_addr *faddr, const __be16 fport)
{
	static u32 inet6_ehash_secret __read_mostly;
	static u32 ipv6_hash_secret __read_mostly;

	u32 lhash, fhash;

	net_get_random_once(&inet6_ehash_secret, sizeof(inet6_ehash_secret));
	net_get_random_once(&ipv6_hash_secret, sizeof(ipv6_hash_secret));

	lhash = (__force u32)laddr->s6_addr32[3];
	fhash = __ipv6_addr_jhash(faddr, ipv6_hash_secret);

	return __inet6_ehashfn(lhash, lport, fhash, fport,
			       inet6_ehash_secret + net_hash_mix(net));
}

/*
 * 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, const int sdif)
{
	struct sock *sk;
	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];


begin:
	sk_nulls_for_each_rcu(sk, node, &head->chain) {
		if (sk->sk_hash != hash)
			continue;
		if (!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))
			continue;
		if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
			goto out;

		if (unlikely(!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))) {
			sock_gen_put(sk);
			goto begin;
		}
		goto found;
	}
	if (get_nulls_value(node) != slot)
		goto begin;
out:
	sk = NULL;
found:
	return sk;
}
EXPORT_SYMBOL(__inet6_lookup_established);

static inline int compute_score(struct sock *sk, struct net *net,
				const unsigned short hnum,
				const struct in6_addr *daddr,
				const int dif, const int sdif, bool exact_dif)
{
	int score = -1;

	if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_num == hnum &&
	    sk->sk_family == PF_INET6) {
		if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
			return -1;

		if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
			return -1;

		score = 1;
		if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
			score++;
	}
	return score;
}

static inline struct sock *lookup_reuseport(struct net *net, struct sock *sk,
					    struct sk_buff *skb, int doff,
					    const struct in6_addr *saddr,
					    __be16 sport,
					    const struct in6_addr *daddr,
					    unsigned short hnum)
{
	struct sock *reuse_sk = NULL;
	u32 phash;

	if (sk->sk_reuseport) {
		phash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
		reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
	}
	return reuse_sk;
}

/* called with rcu_read_lock() */
static struct sock *inet6_lhash2_lookup(struct net *net,
		struct inet_listen_hashbucket *ilb2,
		struct sk_buff *skb, int doff,
		const struct in6_addr *saddr,
		const __be16 sport, const struct in6_addr *daddr,
		const unsigned short hnum, const int dif, const int sdif)
{
	bool exact_dif = inet6_exact_dif_match(net, skb);
	struct inet_connection_sock *icsk;
	struct sock *sk, *result = NULL;
	int score, hiscore = 0;

	inet_lhash2_for_each_icsk_rcu(icsk, &ilb2->head) {
		sk = (struct sock *)icsk;
		score = compute_score(sk, net, hnum, daddr, dif, sdif,
				      exact_dif);
		if (score > hiscore) {
			result = lookup_reuseport(net, sk, skb, doff,
						  saddr, sport, daddr, hnum);
			if (result)
				return result;

			result = sk;
			hiscore = score;
		}
	}

	return result;
}

static inline struct sock *inet6_lookup_run_bpf(struct net *net,
						struct inet_hashinfo *hashinfo,
						struct sk_buff *skb, int doff,
						const struct in6_addr *saddr,
						const __be16 sport,
						const struct in6_addr *daddr,
						const u16 hnum)
{
	struct sock *sk, *reuse_sk;
	bool no_reuseport;

	if (hashinfo != &tcp_hashinfo)
		return NULL; /* only TCP is supported */

	no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_TCP,
					    saddr, sport, daddr, hnum, &sk);
	if (no_reuseport || IS_ERR_OR_NULL(sk))
		return sk;

	reuse_sk = lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum);
	if (reuse_sk)
		sk = reuse_sk;
	return sk;
}

struct sock *inet6_lookup_listener(struct net *net,
		struct inet_hashinfo *hashinfo,
		struct sk_buff *skb, int doff,
		const struct in6_addr *saddr,
		const __be16 sport, const struct in6_addr *daddr,
		const unsigned short hnum, const int dif, const int sdif)
{
	struct inet_listen_hashbucket *ilb2;
	struct sock *result = NULL;
	unsigned int hash2;

	/* Lookup redirect from BPF */
	if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
		result = inet6_lookup_run_bpf(net, hashinfo, skb, doff,
					      saddr, sport, daddr, hnum);
		if (result)
			goto done;
	}

	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
	ilb2 = inet_lhash2_bucket(hashinfo, hash2);

	result = inet6_lhash2_lookup(net, ilb2, skb, doff,
				     saddr, sport, daddr, hnum,
				     dif, sdif);
	if (result)
		goto done;

	/* Lookup lhash2 with in6addr_any */
	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
	ilb2 = inet_lhash2_bucket(hashinfo, hash2);

	result = inet6_lhash2_lookup(net, ilb2, skb, doff,
				     saddr, sport, &in6addr_any, hnum,
				     dif, sdif);
done:
	if (IS_ERR(result))
		return NULL;
	return result;
}
EXPORT_SYMBOL_GPL(inet6_lookup_listener);

struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
			  struct sk_buff *skb, int doff,
			  const struct in6_addr *saddr, const __be16 sport,
			  const struct in6_addr *daddr, const __be16 dport,
			  const int dif)
{
	struct sock *sk;
	bool refcounted;

	sk = __inet6_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
			    ntohs(dport), dif, 0, &refcounted);
	if (sk && !refcounted && !refcount_inc_not_zero(&sk->sk_refcnt))
		sk = NULL;
	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 in6_addr *daddr = &sk->sk_v6_rcv_saddr;
	const struct in6_addr *saddr = &sk->sk_v6_daddr;
	const int dif = sk->sk_bound_dev_if;
	struct net *net = sock_net(sk);
	const int sdif = l3mdev_master_ifindex_by_index(net, dif);
	const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
	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 = NULL;

	spin_lock(lock);

	sk_nulls_for_each(sk2, node, &head->chain) {
		if (sk2->sk_hash != hash)
			continue;

		if (likely(INET6_MATCH(sk2, net, saddr, daddr, ports,
				       dif, sdif))) {
			if (sk2->sk_state == TCP_TIME_WAIT) {
				tw = inet_twsk(sk2);
				if (twsk_unique(sk, sk2, twp))
					break;
			}
			goto not_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);
	sk->sk_hash = hash;
	WARN_ON(!sk_unhashed(sk));
	__sk_nulls_add_node_rcu(sk, &head->chain);
	if (tw) {
		sk_nulls_del_node_init_rcu((struct sock *)tw);
		__NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
	}
	spin_unlock(lock);
	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);

	if (twp) {
		*twp = tw;
	} else if (tw) {
		/* Silly. Should hash-dance instead... */
		inet_twsk_deschedule_put(tw);
	}
	return 0;

not_unique:
	spin_unlock(lock);
	return -EADDRNOTAVAIL;
}

static u32 inet6_sk_port_offset(const struct sock *sk)
{
	const struct inet_sock *inet = inet_sk(sk);

	return secure_ipv6_port_ephemeral(sk->sk_v6_rcv_saddr.s6_addr32,
					  sk->sk_v6_daddr.s6_addr32,
					  inet->inet_dport);
}

int inet6_hash_connect(struct inet_timewait_death_row *death_row,
		       struct sock *sk)
{
	u32 port_offset = 0;

	if (!inet_sk(sk)->inet_num)
		port_offset = inet6_sk_port_offset(sk);
	return __inet_hash_connect(death_row, sk, port_offset,
				   __inet6_check_established);
}
EXPORT_SYMBOL_GPL(inet6_hash_connect);

int inet6_hash(struct sock *sk)
{
	int err = 0;

	if (sk->sk_state != TCP_CLOSE) {
		local_bh_disable();
		err = __inet_hash(sk, NULL);
		local_bh_enable();
	}

	return err;
}
EXPORT_SYMBOL_GPL(inet6_hash);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
5324a040 ACM	2	/*
	3	* INET An implementation of the TCP/IP protocol suite for the LINUX
	4	* operating system. INET is implemented using the BSD Socket
	5	* interface as the means of communication with the user level.
	6	*
	7	* Generic INET6 transport hashtables
	8	*
d8313f5c	9	* Authors: Lotsa people, from code originally in tcp, generalised here
67ba4152	10	* by Arnaldo Carvalho de Melo <acme@mandriva.com>
5324a040 ACM	11	*/
5324a040 ACM	12
5324a040	13	#include <linux/module.h>
d8313f5c	14	#include <linux/random.h>
5324a040	15
c125e80b	16	#include <net/addrconf.h>
5324a040 ACM	17	#include <net/inet_connection_sock.h>
	18	#include <net/inet_hashtables.h>
	19	#include <net/inet6_hashtables.h>
6e5714ea	20	#include <net/secure_seq.h>
d8313f5c	21	#include <net/ip.h>
c125e80b	22	#include <net/sock_reuseport.h>
5324a040	23
1122702f JS	24	extern struct inet_hashinfo tcp_hashinfo;
1122702f JS	25
d1e559d0 ED	26	u32 inet6_ehashfn(const struct net *net,
	27	const struct in6_addr *laddr, const u16 lport,
	28	const struct in6_addr *faddr, const __be16 fport)
b50026b5	29	{
1bbdceef HFS	30	static u32 inet6_ehash_secret __read_mostly;
	31	static u32 ipv6_hash_secret __read_mostly;
	32
	33	u32 lhash, fhash;
	34
	35	net_get_random_once(&inet6_ehash_secret, sizeof(inet6_ehash_secret));
	36	net_get_random_once(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
	37
	38	lhash = (__force u32)laddr->s6_addr32[3];
	39	fhash = __ipv6_addr_jhash(faddr, ipv6_hash_secret);
	40
b50026b5	41	return __inet6_ehashfn(lhash, lport, fhash, fport,
1bbdceef	42	inet6_ehash_secret + net_hash_mix(net));
b50026b5 HFS	43	}
b50026b5 HFS	44
b1a7ffcb DV	45	/*
	46	* Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
	47	* we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
	48	*
	49	* The sockhash lock must be held as a reader here.
	50	*/
d86e0dac PE	51	struct sock __inet6_lookup_established(struct net net,
d86e0dac PE	52	struct inet_hashinfo *hashinfo,
b1a7ffcb	53	const struct in6_addr *saddr,
d2ecd9cc	54	const __be16 sport,
b1a7ffcb DV	55	const struct in6_addr *daddr,
b1a7ffcb DV	56	const u16 hnum,
4297a0ef	57	const int dif, const int sdif)
b1a7ffcb DV	58	{
b1a7ffcb DV	59	struct sock *sk;
3ab5aee7	60	const struct hlist_nulls_node *node;
4f765d84	61	const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
b1a7ffcb DV	62	/* Optimize here for direct hit, only listening connections can
	63	* have wildcards anyways.
	64	*/
33de014c	65	unsigned int hash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
f373b53b	66	unsigned int slot = hash & hashinfo->ehash_mask;
3ab5aee7	67	struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
b1a7ffcb	68
3ab5aee7	69
3ab5aee7 ED	70	begin:
3ab5aee7 ED	71	sk_nulls_for_each_rcu(sk, node, &head->chain) {
ce43b03e ED	72	if (sk->sk_hash != hash)
ce43b03e ED	73	continue;
4297a0ef	74	if (!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))
efe4208f	75	continue;
41c6d650	76	if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
05dbc7b5 ED	77	goto out;
05dbc7b5 ED	78
4297a0ef	79	if (unlikely(!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))) {
efe4208f ED	80	sock_gen_put(sk);
efe4208f ED	81	goto begin;
3ab5aee7	82	}
efe4208f	83	goto found;
b1a7ffcb	84	}
3ab5aee7 ED	85	if (get_nulls_value(node) != slot)
3ab5aee7 ED	86	goto begin;
3ab5aee7	87	out:
05dbc7b5 ED	88	sk = NULL;
05dbc7b5 ED	89	found:
b1a7ffcb DV	90	return sk;
	91	}
	92	EXPORT_SYMBOL(__inet6_lookup_established);
	93
42b16b3f	94	static inline int compute_score(struct sock sk, struct net net,
c25eb3bf ED	95	const unsigned short hnum,
c25eb3bf ED	96	const struct in6_addr *daddr,
4297a0ef	97	const int dif, const int sdif, bool exact_dif)
c25eb3bf ED	98	{
	99	int score = -1;
	100
c720c7e8	101	if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_num == hnum &&
c25eb3bf	102	sk->sk_family == PF_INET6) {
0ee58dad PO	103	if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
0ee58dad PO	104	return -1;
c25eb3bf	105
0ee58dad	106	if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
e7819058	107	return -1;
4297a0ef	108
0ee58dad	109	score = 1;
7170a977	110	if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
70da268b	111	score++;
c25eb3bf ED	112	}
	113	return score;
	114	}
	115
5df65312 JS	116	static inline struct sock lookup_reuseport(struct net net, struct sock *sk,
	117	struct sk_buff *skb, int doff,
	118	const struct in6_addr *saddr,
	119	__be16 sport,
	120	const struct in6_addr *daddr,
	121	unsigned short hnum)
	122	{
	123	struct sock *reuse_sk = NULL;
	124	u32 phash;
	125
	126	if (sk->sk_reuseport) {
	127	phash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
	128	reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
	129	}
	130	return reuse_sk;
	131	}
	132
3b24d854	133	/* called with rcu_read_lock() */
61b7c691 MKL	134	static struct sock inet6_lhash2_lookup(struct net net,
	135	struct inet_listen_hashbucket *ilb2,
	136	struct sk_buff *skb, int doff,
	137	const struct in6_addr *saddr,
	138	const __be16 sport, const struct in6_addr *daddr,
	139	const unsigned short hnum, const int dif, const int sdif)
	140	{
	141	bool exact_dif = inet6_exact_dif_match(net, skb);
	142	struct inet_connection_sock *icsk;
	143	struct sock sk, result = NULL;
	144	int score, hiscore = 0;
61b7c691 MKL	145
	146	inet_lhash2_for_each_icsk_rcu(icsk, &ilb2->head) {
	147	sk = (struct sock *)icsk;
	148	score = compute_score(sk, net, hnum, daddr, dif, sdif,
	149	exact_dif);
	150	if (score > hiscore) {
5df65312 JS	151	result = lookup_reuseport(net, sk, skb, doff,
	152	saddr, sport, daddr, hnum);
	153	if (result)
	154	return result;
	155
61b7c691 MKL	156	result = sk;
	157	hiscore = score;
	158	}
	159	}
	160
	161	return result;
	162	}
	163
1122702f JS	164	static inline struct sock inet6_lookup_run_bpf(struct net net,
	165	struct inet_hashinfo *hashinfo,
	166	struct sk_buff *skb, int doff,
	167	const struct in6_addr *saddr,
	168	const __be16 sport,
	169	const struct in6_addr *daddr,
	170	const u16 hnum)
	171	{
	172	struct sock sk, reuse_sk;
	173	bool no_reuseport;
	174
	175	if (hashinfo != &tcp_hashinfo)
	176	return NULL; /* only TCP is supported */
	177
	178	no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_TCP,
	179	saddr, sport, daddr, hnum, &sk);
	180	if (no_reuseport \|\| IS_ERR_OR_NULL(sk))
	181	return sk;
	182
	183	reuse_sk = lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum);
	184	if (reuse_sk)
	185	sk = reuse_sk;
	186	return sk;
	187	}
	188
d86e0dac	189	struct sock inet6_lookup_listener(struct net net,
a583636a CG	190	struct inet_hashinfo *hashinfo,
	191	struct sk_buff *skb, int doff,
	192	const struct in6_addr *saddr,
5ba24953	193	const __be16 sport, const struct in6_addr *daddr,
4297a0ef	194	const unsigned short hnum, const int dif, const int sdif)
5324a040	195	{
61b7c691	196	struct inet_listen_hashbucket *ilb2;
0ee58dad	197	struct sock *result = NULL;
61b7c691	198	unsigned int hash2;
61b7c691	199
1122702f JS	200	/* Lookup redirect from BPF */
	201	if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
	202	result = inet6_lookup_run_bpf(net, hashinfo, skb, doff,
	203	saddr, sport, daddr, hnum);
	204	if (result)
	205	goto done;
	206	}
	207
61b7c691 MKL	208	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
61b7c691 MKL	209	ilb2 = inet_lhash2_bucket(hashinfo, hash2);
61b7c691 MKL	210
	211	result = inet6_lhash2_lookup(net, ilb2, skb, doff,
	212	saddr, sport, daddr, hnum,
	213	dif, sdif);
	214	if (result)
8217ca65	215	goto done;
61b7c691 MKL	216
61b7c691 MKL	217	/* Lookup lhash2 with in6addr_any */
61b7c691 MKL	218	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
61b7c691 MKL	219	ilb2 = inet_lhash2_bucket(hashinfo, hash2);
61b7c691	220
8217ca65	221	result = inet6_lhash2_lookup(net, ilb2, skb, doff,
0ee58dad	222	saddr, sport, &in6addr_any, hnum,
8217ca65	223	dif, sdif);
8217ca65	224	done:
26f8113c	225	if (IS_ERR(result))
8217ca65	226	return NULL;
5324a040 ACM	227	return result;
5324a040 ACM	228	}
5324a040 ACM	229	EXPORT_SYMBOL_GPL(inet6_lookup_listener);
5324a040 ACM	230
d86e0dac	231	struct sock inet6_lookup(struct net net, struct inet_hashinfo *hashinfo,
a583636a	232	struct sk_buff *skb, int doff,
d2ecd9cc AV	233	const struct in6_addr *saddr, const __be16 sport,
d2ecd9cc AV	234	const struct in6_addr *daddr, const __be16 dport,
5324a040 ACM	235	const int dif)
	236	{
	237	struct sock *sk;
3b24d854	238	bool refcounted;
5324a040	239
a583636a	240	sk = __inet6_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
4297a0ef	241	ntohs(dport), dif, 0, &refcounted);
41c6d650	242	if (sk && !refcounted && !refcount_inc_not_zero(&sk->sk_refcnt))
3b24d854	243	sk = NULL;
5324a040 ACM	244	return sk;
5324a040 ACM	245	}
5324a040	246	EXPORT_SYMBOL_GPL(inet6_lookup);
d8313f5c ACM	247
	248	static int __inet6_check_established(struct inet_timewait_death_row *death_row,
	249	struct sock *sk, const __u16 lport,
	250	struct inet_timewait_sock **twp)
	251	{
	252	struct inet_hashinfo *hinfo = death_row->hashinfo;
3759fa9c	253	struct inet_sock *inet = inet_sk(sk);
efe4208f ED	254	const struct in6_addr *daddr = &sk->sk_v6_rcv_saddr;
efe4208f ED	255	const struct in6_addr *saddr = &sk->sk_v6_daddr;
d8313f5c	256	const int dif = sk->sk_bound_dev_if;
33de014c	257	struct net *net = sock_net(sk);
4297a0ef DA	258	const int sdif = l3mdev_master_ifindex_by_index(net, dif);
4297a0ef DA	259	const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
33de014c	260	const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr,
c720c7e8	261	inet->inet_dport);
d8313f5c	262	struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
9db66bdc	263	spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
d8313f5c	264	struct sock *sk2;
3ab5aee7	265	const struct hlist_nulls_node *node;
05dbc7b5	266	struct inet_timewait_sock *tw = NULL;
d8313f5c	267
9db66bdc	268	spin_lock(lock);
d8313f5c	269
05dbc7b5	270	sk_nulls_for_each(sk2, node, &head->chain) {
ce43b03e ED	271	if (sk2->sk_hash != hash)
ce43b03e ED	272	continue;
d8313f5c	273
4297a0ef DA	274	if (likely(INET6_MATCH(sk2, net, saddr, daddr, ports,
4297a0ef DA	275	dif, sdif))) {
efe4208f	276	if (sk2->sk_state == TCP_TIME_WAIT) {
05dbc7b5 ED	277	tw = inet_twsk(sk2);
05dbc7b5 ED	278	if (twsk_unique(sk, sk2, twp))
efe4208f	279	break;
05dbc7b5	280	}
d8313f5c	281	goto not_unique;
efe4208f	282	}
d8313f5c ACM	283	}
d8313f5c ACM	284
3759fa9c	285	/* Must record num and sport now. Otherwise we will see
efe4208f ED	286	* in hash table socket with a funny identity.
efe4208f ED	287	*/
c720c7e8 ED	288	inet->inet_num = lport;
c720c7e8 ED	289	inet->inet_sport = htons(lport);
13475a30	290	sk->sk_hash = hash;
547b792c	291	WARN_ON(!sk_unhashed(sk));
3ab5aee7	292	__sk_nulls_add_node_rcu(sk, &head->chain);
13475a30	293	if (tw) {
fc01538f	294	sk_nulls_del_node_init_rcu((struct sock *)tw);
02a1d6e7	295	__NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
13475a30	296	}
9db66bdc	297	spin_unlock(lock);
c29a0bc4	298	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
d8313f5c	299
13475a30	300	if (twp) {
d8313f5c	301	*twp = tw;
13475a30	302	} else if (tw) {
d8313f5c	303	/* Silly. Should hash-dance instead... */
dbe7faa4	304	inet_twsk_deschedule_put(tw);
d8313f5c ACM	305	}
	306	return 0;
	307
	308	not_unique:
9db66bdc	309	spin_unlock(lock);
d8313f5c ACM	310	return -EADDRNOTAVAIL;
	311	}
	312
e2baad9e	313	static u32 inet6_sk_port_offset(const struct sock *sk)
d8313f5c ACM	314	{
d8313f5c ACM	315	const struct inet_sock *inet = inet_sk(sk);
efe4208f ED	316
	317	return secure_ipv6_port_ephemeral(sk->sk_v6_rcv_saddr.s6_addr32,
	318	sk->sk_v6_daddr.s6_addr32,
c720c7e8	319	inet->inet_dport);
d8313f5c ACM	320	}
	321
	322	int inet6_hash_connect(struct inet_timewait_death_row *death_row,
	323	struct sock *sk)
	324	{
e2baad9e ED	325	u32 port_offset = 0;
	326
	327	if (!inet_sk(sk)->inet_num)
	328	port_offset = inet6_sk_port_offset(sk);
	329	return __inet_hash_connect(death_row, sk, port_offset,
b4d6444e	330	__inet6_check_established);
d8313f5c	331	}
d8313f5c	332	EXPORT_SYMBOL_GPL(inet6_hash_connect);
496611d7 CG	333
	334	int inet6_hash(struct sock *sk)
	335	{
e4cabca5 CG	336	int err = 0;
e4cabca5 CG	337
496611d7 CG	338	if (sk->sk_state != TCP_CLOSE) {
496611d7 CG	339	local_bh_disable();
fe38d2a1	340	err = __inet_hash(sk, NULL);
496611d7 CG	341	local_bh_enable();
	342	}
	343
e4cabca5	344	return err;
496611d7 CG	345	}
496611d7 CG	346	EXPORT_SYMBOL_GPL(inet6_hash);