1/*
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.
5 *
6 * Generic INET transport hashtables
7 *
8 * Authors: Lotsa people, from code originally in tcp
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 */
15
16#include <linux/module.h>
17#include <linux/random.h>
18#include <linux/sched.h>
19#include <linux/slab.h>
20#include <linux/wait.h>
21#include <linux/vmalloc.h>
22#include <linux/memblock.h>
23
24#include <net/addrconf.h>
25#include <net/inet_connection_sock.h>
26#include <net/inet_hashtables.h>
27#include <net/secure_seq.h>
28#include <net/ip.h>
29#include <net/tcp.h>
30#include <net/sock_reuseport.h>
31
32static u32 inet_ehashfn(const struct net *net, const __be32 laddr,
33 const __u16 lport, const __be32 faddr,
34 const __be16 fport)
35{
36 static u32 inet_ehash_secret __read_mostly;
37
38 net_get_random_once(&inet_ehash_secret, sizeof(inet_ehash_secret));
39
40 return __inet_ehashfn(laddr, lport, faddr, fport,
41 inet_ehash_secret + net_hash_mix(net));
42}
43
44/* This function handles inet_sock, but also timewait and request sockets
45 * for IPv4/IPv6.
46 */
47static u32 sk_ehashfn(const struct sock *sk)
48{
49#if IS_ENABLED(CONFIG_IPV6)
50 if (sk->sk_family == AF_INET6 &&
51 !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
52 return inet6_ehashfn(sock_net(sk),
53 &sk->sk_v6_rcv_saddr, sk->sk_num,
54 &sk->sk_v6_daddr, sk->sk_dport);
55#endif
56 return inet_ehashfn(sock_net(sk),
57 sk->sk_rcv_saddr, sk->sk_num,
58 sk->sk_daddr, sk->sk_dport);
59}
60
61/*
62 * Allocate and initialize a new local port bind bucket.
63 * The bindhash mutex for snum's hash chain must be held here.
64 */
65struct inet_bind_bucket *inet_bind_bucket_create(struct kmem_cache *cachep,
66 struct net *net,
67 struct inet_bind_hashbucket *head,
68 const unsigned short snum,
69 int l3mdev)
70{
71 struct inet_bind_bucket *tb = kmem_cache_alloc(cachep, GFP_ATOMIC);
72
73 if (tb) {
74 write_pnet(&tb->ib_net, net);
75 tb->l3mdev = l3mdev;
76 tb->port = snum;
77 tb->fastreuse = 0;
78 tb->fastreuseport = 0;
79 INIT_HLIST_HEAD(&tb->owners);
80 hlist_add_head(&tb->node, &head->chain);
81 }
82 return tb;
83}
84
85/*
86 * Caller must hold hashbucket lock for this tb with local BH disabled
87 */
88void inet_bind_bucket_destroy(struct kmem_cache *cachep, struct inet_bind_bucket *tb)
89{
90 if (hlist_empty(&tb->owners)) {
91 __hlist_del(&tb->node);
92 kmem_cache_free(cachep, tb);
93 }
94}
95
96void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
97 const unsigned short snum)
98{
99 inet_sk(sk)->inet_num = snum;
100 sk_add_bind_node(sk, &tb->owners);
101 inet_csk(sk)->icsk_bind_hash = tb;
102}
103
104/*
105 * Get rid of any references to a local port held by the given sock.
106 */
107static void __inet_put_port(struct sock *sk)
108{
109 struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
110 const int bhash = inet_bhashfn(sock_net(sk), inet_sk(sk)->inet_num,
111 hashinfo->bhash_size);
112 struct inet_bind_hashbucket *head = &hashinfo->bhash[bhash];
113 struct inet_bind_bucket *tb;
114
115 spin_lock(&head->lock);
116 tb = inet_csk(sk)->icsk_bind_hash;
117 __sk_del_bind_node(sk);
118 inet_csk(sk)->icsk_bind_hash = NULL;
119 inet_sk(sk)->inet_num = 0;
120 inet_bind_bucket_destroy(hashinfo->bind_bucket_cachep, tb);
121 spin_unlock(&head->lock);
122}
123
124void inet_put_port(struct sock *sk)
125{
126 local_bh_disable();
127 __inet_put_port(sk);
128 local_bh_enable();
129}
130EXPORT_SYMBOL(inet_put_port);
131
132int __inet_inherit_port(const struct sock *sk, struct sock *child)
133{
134 struct inet_hashinfo *table = sk->sk_prot->h.hashinfo;
135 unsigned short port = inet_sk(child)->inet_num;
136 const int bhash = inet_bhashfn(sock_net(sk), port,
137 table->bhash_size);
138 struct inet_bind_hashbucket *head = &table->bhash[bhash];
139 struct inet_bind_bucket *tb;
140 int l3mdev;
141
142 spin_lock(&head->lock);
143 tb = inet_csk(sk)->icsk_bind_hash;
144 if (unlikely(!tb)) {
145 spin_unlock(&head->lock);
146 return -ENOENT;
147 }
148 if (tb->port != port) {
149 l3mdev = inet_sk_bound_l3mdev(sk);
150
151 /* NOTE: using tproxy and redirecting skbs to a proxy
152 * on a different listener port breaks the assumption
153 * that the listener socket's icsk_bind_hash is the same
154 * as that of the child socket. We have to look up or
155 * create a new bind bucket for the child here. */
156 inet_bind_bucket_for_each(tb, &head->chain) {
157 if (net_eq(ib_net(tb), sock_net(sk)) &&
158 tb->l3mdev == l3mdev && tb->port == port)
159 break;
160 }
161 if (!tb) {
162 tb = inet_bind_bucket_create(table->bind_bucket_cachep,
163 sock_net(sk), head, port,
164 l3mdev);
165 if (!tb) {
166 spin_unlock(&head->lock);
167 return -ENOMEM;
168 }
169 }
170 }
171 inet_bind_hash(child, tb, port);
172 spin_unlock(&head->lock);
173
174 return 0;
175}
176EXPORT_SYMBOL_GPL(__inet_inherit_port);
177
178static struct inet_listen_hashbucket *
179inet_lhash2_bucket_sk(struct inet_hashinfo *h, struct sock *sk)
180{
181 u32 hash;
182
183#if IS_ENABLED(CONFIG_IPV6)
184 if (sk->sk_family == AF_INET6)
185 hash = ipv6_portaddr_hash(sock_net(sk),
186 &sk->sk_v6_rcv_saddr,
187 inet_sk(sk)->inet_num);
188 else
189#endif
190 hash = ipv4_portaddr_hash(sock_net(sk),
191 inet_sk(sk)->inet_rcv_saddr,
192 inet_sk(sk)->inet_num);
193 return inet_lhash2_bucket(h, hash);
194}
195
196static void inet_hash2(struct inet_hashinfo *h, struct sock *sk)
197{
198 struct inet_listen_hashbucket *ilb2;
199
200 if (!h->lhash2)
201 return;
202
203 ilb2 = inet_lhash2_bucket_sk(h, sk);
204
205 spin_lock(&ilb2->lock);
206 if (sk->sk_reuseport && sk->sk_family == AF_INET6)
207 hlist_add_tail_rcu(&inet_csk(sk)->icsk_listen_portaddr_node,
208 &ilb2->head);
209 else
210 hlist_add_head_rcu(&inet_csk(sk)->icsk_listen_portaddr_node,
211 &ilb2->head);
212 ilb2->count++;
213 spin_unlock(&ilb2->lock);
214}
215
216static void inet_unhash2(struct inet_hashinfo *h, struct sock *sk)
217{
218 struct inet_listen_hashbucket *ilb2;
219
220 if (!h->lhash2 ||
221 WARN_ON_ONCE(hlist_unhashed(&inet_csk(sk)->icsk_listen_portaddr_node)))
222 return;
223
224 ilb2 = inet_lhash2_bucket_sk(h, sk);
225
226 spin_lock(&ilb2->lock);
227 hlist_del_init_rcu(&inet_csk(sk)->icsk_listen_portaddr_node);
228 ilb2->count--;
229 spin_unlock(&ilb2->lock);
230}
231
232static inline int compute_score(struct sock *sk, struct net *net,
233 const unsigned short hnum, const __be32 daddr,
234 const int dif, const int sdif, bool exact_dif)
235{
236 int score = -1;
237
238 if (net_eq(sock_net(sk), net) && sk->sk_num == hnum &&
239 !ipv6_only_sock(sk)) {
240 if (sk->sk_rcv_saddr != daddr)
241 return -1;
242
243 if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
244 return -1;
245
246 score = sk->sk_family == PF_INET ? 2 : 1;
247 if (sk->sk_incoming_cpu == raw_smp_processor_id())
248 score++;
249 }
250 return score;
251}
252
253/*
254 * Here are some nice properties to exploit here. The BSD API
255 * does not allow a listening sock to specify the remote port nor the
256 * remote address for the connection. So always assume those are both
257 * wildcarded during the search since they can never be otherwise.
258 */
259
260/* called with rcu_read_lock() : No refcount taken on the socket */
261static struct sock *inet_lhash2_lookup(struct net *net,
262 struct inet_listen_hashbucket *ilb2,
263 struct sk_buff *skb, int doff,
264 const __be32 saddr, __be16 sport,
265 const __be32 daddr, const unsigned short hnum,
266 const int dif, const int sdif)
267{
268 bool exact_dif = inet_exact_dif_match(net, skb);
269 struct inet_connection_sock *icsk;
270 struct sock *sk, *result = NULL;
271 int score, hiscore = 0;
272 u32 phash = 0;
273
274 inet_lhash2_for_each_icsk_rcu(icsk, &ilb2->head) {
275 sk = (struct sock *)icsk;
276 score = compute_score(sk, net, hnum, daddr,
277 dif, sdif, exact_dif);
278 if (score > hiscore) {
279 if (sk->sk_reuseport) {
280 phash = inet_ehashfn(net, daddr, hnum,
281 saddr, sport);
282 result = reuseport_select_sock(sk, phash,
283 skb, doff);
284 if (result)
285 return result;
286 }
287 result = sk;
288 hiscore = score;
289 }
290 }
291
292 return result;
293}
294
295struct sock *__inet_lookup_listener(struct net *net,
296 struct inet_hashinfo *hashinfo,
297 struct sk_buff *skb, int doff,
298 const __be32 saddr, __be16 sport,
299 const __be32 daddr, const unsigned short hnum,
300 const int dif, const int sdif)
301{
302 struct inet_listen_hashbucket *ilb2;
303 struct sock *result = NULL;
304 unsigned int hash2;
305
306 hash2 = ipv4_portaddr_hash(net, daddr, hnum);
307 ilb2 = inet_lhash2_bucket(hashinfo, hash2);
308
309 result = inet_lhash2_lookup(net, ilb2, skb, doff,
310 saddr, sport, daddr, hnum,
311 dif, sdif);
312 if (result)
313 goto done;
314
315 /* Lookup lhash2 with INADDR_ANY */
316 hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
317 ilb2 = inet_lhash2_bucket(hashinfo, hash2);
318
319 result = inet_lhash2_lookup(net, ilb2, skb, doff,
320 saddr, sport, htonl(INADDR_ANY), hnum,
321 dif, sdif);
322done:
323 if (unlikely(IS_ERR(result)))
324 return NULL;
325 return result;
326}
327EXPORT_SYMBOL_GPL(__inet_lookup_listener);
328
329/* All sockets share common refcount, but have different destructors */
330void sock_gen_put(struct sock *sk)
331{
332 if (!refcount_dec_and_test(&sk->sk_refcnt))
333 return;
334
335 if (sk->sk_state == TCP_TIME_WAIT)
336 inet_twsk_free(inet_twsk(sk));
337 else if (sk->sk_state == TCP_NEW_SYN_RECV)
338 reqsk_free(inet_reqsk(sk));
339 else
340 sk_free(sk);
341}
342EXPORT_SYMBOL_GPL(sock_gen_put);
343
344void sock_edemux(struct sk_buff *skb)
345{
346 sock_gen_put(skb->sk);
347}
348EXPORT_SYMBOL(sock_edemux);
349
350struct sock *__inet_lookup_established(struct net *net,
351 struct inet_hashinfo *hashinfo,
352 const __be32 saddr, const __be16 sport,
353 const __be32 daddr, const u16 hnum,
354 const int dif, const int sdif)
355{
356 INET_ADDR_COOKIE(acookie, saddr, daddr);
357 const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
358 struct sock *sk;
359 const struct hlist_nulls_node *node;
360 /* Optimize here for direct hit, only listening connections can
361 * have wildcards anyways.
362 */
363 unsigned int hash = inet_ehashfn(net, daddr, hnum, saddr, sport);
364 unsigned int slot = hash & hashinfo->ehash_mask;
365 struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
366
367begin:
368 sk_nulls_for_each_rcu(sk, node, &head->chain) {
369 if (sk->sk_hash != hash)
370 continue;
371 if (likely(INET_MATCH(sk, net, acookie,
372 saddr, daddr, ports, dif, sdif))) {
373 if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
374 goto out;
375 if (unlikely(!INET_MATCH(sk, net, acookie,
376 saddr, daddr, ports,
377 dif, sdif))) {
378 sock_gen_put(sk);
379 goto begin;
380 }
381 goto found;
382 }
383 }
384 /*
385 * if the nulls value we got at the end of this lookup is
386 * not the expected one, we must restart lookup.
387 * We probably met an item that was moved to another chain.
388 */
389 if (get_nulls_value(node) != slot)
390 goto begin;
391out:
392 sk = NULL;
393found:
394 return sk;
395}
396EXPORT_SYMBOL_GPL(__inet_lookup_established);
397
398/* called with local bh disabled */
399static int __inet_check_established(struct inet_timewait_death_row *death_row,
400 struct sock *sk, __u16 lport,
401 struct inet_timewait_sock **twp)
402{
403 struct inet_hashinfo *hinfo = death_row->hashinfo;
404 struct inet_sock *inet = inet_sk(sk);
405 __be32 daddr = inet->inet_rcv_saddr;
406 __be32 saddr = inet->inet_daddr;
407 int dif = sk->sk_bound_dev_if;
408 struct net *net = sock_net(sk);
409 int sdif = l3mdev_master_ifindex_by_index(net, dif);
410 INET_ADDR_COOKIE(acookie, saddr, daddr);
411 const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
412 unsigned int hash = inet_ehashfn(net, daddr, lport,
413 saddr, inet->inet_dport);
414 struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
415 spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
416 struct sock *sk2;
417 const struct hlist_nulls_node *node;
418 struct inet_timewait_sock *tw = NULL;
419
420 spin_lock(lock);
421
422 sk_nulls_for_each(sk2, node, &head->chain) {
423 if (sk2->sk_hash != hash)
424 continue;
425
426 if (likely(INET_MATCH(sk2, net, acookie,
427 saddr, daddr, ports, dif, sdif))) {
428 if (sk2->sk_state == TCP_TIME_WAIT) {
429 tw = inet_twsk(sk2);
430 if (twsk_unique(sk, sk2, twp))
431 break;
432 }
433 goto not_unique;
434 }
435 }
436
437 /* Must record num and sport now. Otherwise we will see
438 * in hash table socket with a funny identity.
439 */
440 inet->inet_num = lport;
441 inet->inet_sport = htons(lport);
442 sk->sk_hash = hash;
443 WARN_ON(!sk_unhashed(sk));
444 __sk_nulls_add_node_rcu(sk, &head->chain);
445 if (tw) {
446 sk_nulls_del_node_init_rcu((struct sock *)tw);
447 __NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
448 }
449 spin_unlock(lock);
450 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
451
452 if (twp) {
453 *twp = tw;
454 } else if (tw) {
455 /* Silly. Should hash-dance instead... */
456 inet_twsk_deschedule_put(tw);
457 }
458 return 0;
459
460not_unique:
461 spin_unlock(lock);
462 return -EADDRNOTAVAIL;
463}
464
465static u32 inet_sk_port_offset(const struct sock *sk)
466{
467 const struct inet_sock *inet = inet_sk(sk);
468
469 return secure_ipv4_port_ephemeral(inet->inet_rcv_saddr,
470 inet->inet_daddr,
471 inet->inet_dport);
472}
473
474/* insert a socket into ehash, and eventually remove another one
475 * (The another one can be a SYN_RECV or TIMEWAIT
476 */
477bool inet_ehash_insert(struct sock *sk, struct sock *osk)
478{
479 struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
480 struct hlist_nulls_head *list;
481 struct inet_ehash_bucket *head;
482 spinlock_t *lock;
483 bool ret = true;
484
485 WARN_ON_ONCE(!sk_unhashed(sk));
486
487 sk->sk_hash = sk_ehashfn(sk);
488 head = inet_ehash_bucket(hashinfo, sk->sk_hash);
489 list = &head->chain;
490 lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
491
492 spin_lock(lock);
493 if (osk) {
494 WARN_ON_ONCE(sk->sk_hash != osk->sk_hash);
495 ret = sk_nulls_del_node_init_rcu(osk);
496 }
497 if (ret)
498 __sk_nulls_add_node_rcu(sk, list);
499 spin_unlock(lock);
500 return ret;
501}
502
503bool inet_ehash_nolisten(struct sock *sk, struct sock *osk)
504{
505 bool ok = inet_ehash_insert(sk, osk);
506
507 if (ok) {
508 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
509 } else {
510 percpu_counter_inc(sk->sk_prot->orphan_count);
511 inet_sk_set_state(sk, TCP_CLOSE);
512 sock_set_flag(sk, SOCK_DEAD);
513 inet_csk_destroy_sock(sk);
514 }
515 return ok;
516}
517EXPORT_SYMBOL_GPL(inet_ehash_nolisten);
518
519static int inet_reuseport_add_sock(struct sock *sk,
520 struct inet_listen_hashbucket *ilb)
521{
522 struct inet_bind_bucket *tb = inet_csk(sk)->icsk_bind_hash;
523 struct sock *sk2;
524 kuid_t uid = sock_i_uid(sk);
525
526 sk_for_each_rcu(sk2, &ilb->head) {
527 if (sk2 != sk &&
528 sk2->sk_family == sk->sk_family &&
529 ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
530 sk2->sk_bound_dev_if == sk->sk_bound_dev_if &&
531 inet_csk(sk2)->icsk_bind_hash == tb &&
532 sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
533 inet_rcv_saddr_equal(sk, sk2, false))
534 return reuseport_add_sock(sk, sk2,
535 inet_rcv_saddr_any(sk));
536 }
537
538 return reuseport_alloc(sk, inet_rcv_saddr_any(sk));
539}
540
541int __inet_hash(struct sock *sk, struct sock *osk)
542{
543 struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
544 struct inet_listen_hashbucket *ilb;
545 int err = 0;
546
547 if (sk->sk_state != TCP_LISTEN) {
548 inet_ehash_nolisten(sk, osk);
549 return 0;
550 }
551 WARN_ON(!sk_unhashed(sk));
552 ilb = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
553
554 spin_lock(&ilb->lock);
555 if (sk->sk_reuseport) {
556 err = inet_reuseport_add_sock(sk, ilb);
557 if (err)
558 goto unlock;
559 }
560 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
561 sk->sk_family == AF_INET6)
562 hlist_add_tail_rcu(&sk->sk_node, &ilb->head);
563 else
564 hlist_add_head_rcu(&sk->sk_node, &ilb->head);
565 inet_hash2(hashinfo, sk);
566 ilb->count++;
567 sock_set_flag(sk, SOCK_RCU_FREE);
568 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
569unlock:
570 spin_unlock(&ilb->lock);
571
572 return err;
573}
574EXPORT_SYMBOL(__inet_hash);
575
576int inet_hash(struct sock *sk)
577{
578 int err = 0;
579
580 if (sk->sk_state != TCP_CLOSE) {
581 local_bh_disable();
582 err = __inet_hash(sk, NULL);
583 local_bh_enable();
584 }
585
586 return err;
587}
588EXPORT_SYMBOL_GPL(inet_hash);
589
590void inet_unhash(struct sock *sk)
591{
592 struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo;
593 struct inet_listen_hashbucket *ilb = NULL;
594 spinlock_t *lock;
595
596 if (sk_unhashed(sk))
597 return;
598
599 if (sk->sk_state == TCP_LISTEN) {
600 ilb = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
601 lock = &ilb->lock;
602 } else {
603 lock = inet_ehash_lockp(hashinfo, sk->sk_hash);
604 }
605 spin_lock_bh(lock);
606 if (sk_unhashed(sk))
607 goto unlock;
608
609 if (rcu_access_pointer(sk->sk_reuseport_cb))
610 reuseport_detach_sock(sk);
611 if (ilb) {
612 inet_unhash2(hashinfo, sk);
613 __sk_del_node_init(sk);
614 ilb->count--;
615 } else {
616 __sk_nulls_del_node_init_rcu(sk);
617 }
618 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
619unlock:
620 spin_unlock_bh(lock);
621}
622EXPORT_SYMBOL_GPL(inet_unhash);
623
624int __inet_hash_connect(struct inet_timewait_death_row *death_row,
625 struct sock *sk, u32 port_offset,
626 int (*check_established)(struct inet_timewait_death_row *,
627 struct sock *, __u16, struct inet_timewait_sock **))
628{
629 struct inet_hashinfo *hinfo = death_row->hashinfo;
630 struct inet_timewait_sock *tw = NULL;
631 struct inet_bind_hashbucket *head;
632 int port = inet_sk(sk)->inet_num;
633 struct net *net = sock_net(sk);
634 struct inet_bind_bucket *tb;
635 u32 remaining, offset;
636 int ret, i, low, high;
637 static u32 hint;
638 int l3mdev;
639
640 if (port) {
641 head = &hinfo->bhash[inet_bhashfn(net, port,
642 hinfo->bhash_size)];
643 tb = inet_csk(sk)->icsk_bind_hash;
644 spin_lock_bh(&head->lock);
645 if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
646 inet_ehash_nolisten(sk, NULL);
647 spin_unlock_bh(&head->lock);
648 return 0;
649 }
650 spin_unlock(&head->lock);
651 /* No definite answer... Walk to established hash table */
652 ret = check_established(death_row, sk, port, NULL);
653 local_bh_enable();
654 return ret;
655 }
656
657 l3mdev = inet_sk_bound_l3mdev(sk);
658
659 inet_get_local_port_range(net, &low, &high);
660 high++; /* [32768, 60999] -> [32768, 61000[ */
661 remaining = high - low;
662 if (likely(remaining > 1))
663 remaining &= ~1U;
664
665 offset = (hint + port_offset) % remaining;
666 /* In first pass we try ports of @low parity.
667 * inet_csk_get_port() does the opposite choice.
668 */
669 offset &= ~1U;
670other_parity_scan:
671 port = low + offset;
672 for (i = 0; i < remaining; i += 2, port += 2) {
673 if (unlikely(port >= high))
674 port -= remaining;
675 if (inet_is_local_reserved_port(net, port))
676 continue;
677 head = &hinfo->bhash[inet_bhashfn(net, port,
678 hinfo->bhash_size)];
679 spin_lock_bh(&head->lock);
680
681 /* Does not bother with rcv_saddr checks, because
682 * the established check is already unique enough.
683 */
684 inet_bind_bucket_for_each(tb, &head->chain) {
685 if (net_eq(ib_net(tb), net) && tb->l3mdev == l3mdev &&
686 tb->port == port) {
687 if (tb->fastreuse >= 0 ||
688 tb->fastreuseport >= 0)
689 goto next_port;
690 WARN_ON(hlist_empty(&tb->owners));
691 if (!check_established(death_row, sk,
692 port, &tw))
693 goto ok;
694 goto next_port;
695 }
696 }
697
698 tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
699 net, head, port, l3mdev);
700 if (!tb) {
701 spin_unlock_bh(&head->lock);
702 return -ENOMEM;
703 }
704 tb->fastreuse = -1;
705 tb->fastreuseport = -1;
706 goto ok;
707next_port:
708 spin_unlock_bh(&head->lock);
709 cond_resched();
710 }
711
712 offset++;
713 if ((offset & 1) && remaining > 1)
714 goto other_parity_scan;
715
716 return -EADDRNOTAVAIL;
717
718ok:
719 hint += i + 2;
720
721 /* Head lock still held and bh's disabled */
722 inet_bind_hash(sk, tb, port);
723 if (sk_unhashed(sk)) {
724 inet_sk(sk)->inet_sport = htons(port);
725 inet_ehash_nolisten(sk, (struct sock *)tw);
726 }
727 if (tw)
728 inet_twsk_bind_unhash(tw, hinfo);
729 spin_unlock(&head->lock);
730 if (tw)
731 inet_twsk_deschedule_put(tw);
732 local_bh_enable();
733 return 0;
734}
735
736/*
737 * Bind a port for a connect operation and hash it.
738 */
739int inet_hash_connect(struct inet_timewait_death_row *death_row,
740 struct sock *sk)
741{
742 u32 port_offset = 0;
743
744 if (!inet_sk(sk)->inet_num)
745 port_offset = inet_sk_port_offset(sk);
746 return __inet_hash_connect(death_row, sk, port_offset,
747 __inet_check_established);
748}
749EXPORT_SYMBOL_GPL(inet_hash_connect);
750
751void inet_hashinfo_init(struct inet_hashinfo *h)
752{
753 int i;
754
755 for (i = 0; i < INET_LHTABLE_SIZE; i++) {
756 spin_lock_init(&h->listening_hash[i].lock);
757 INIT_HLIST_HEAD(&h->listening_hash[i].head);
758 h->listening_hash[i].count = 0;
759 }
760
761 h->lhash2 = NULL;
762}
763EXPORT_SYMBOL_GPL(inet_hashinfo_init);
764
765static void init_hashinfo_lhash2(struct inet_hashinfo *h)
766{
767 int i;
768
769 for (i = 0; i <= h->lhash2_mask; i++) {
770 spin_lock_init(&h->lhash2[i].lock);
771 INIT_HLIST_HEAD(&h->lhash2[i].head);
772 h->lhash2[i].count = 0;
773 }
774}
775
776void __init inet_hashinfo2_init(struct inet_hashinfo *h, const char *name,
777 unsigned long numentries, int scale,
778 unsigned long low_limit,
779 unsigned long high_limit)
780{
781 h->lhash2 = alloc_large_system_hash(name,
782 sizeof(*h->lhash2),
783 numentries,
784 scale,
785 0,
786 NULL,
787 &h->lhash2_mask,
788 low_limit,
789 high_limit);
790 init_hashinfo_lhash2(h);
791}
792
793int inet_hashinfo2_init_mod(struct inet_hashinfo *h)
794{
795 h->lhash2 = kmalloc_array(INET_LHTABLE_SIZE, sizeof(*h->lhash2), GFP_KERNEL);
796 if (!h->lhash2)
797 return -ENOMEM;
798
799 h->lhash2_mask = INET_LHTABLE_SIZE - 1;
800 /* INET_LHTABLE_SIZE must be a power of 2 */
801 BUG_ON(INET_LHTABLE_SIZE & h->lhash2_mask);
802
803 init_hashinfo_lhash2(h);
804 return 0;
805}
806EXPORT_SYMBOL_GPL(inet_hashinfo2_init_mod);
807
808int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
809{
810 unsigned int locksz = sizeof(spinlock_t);
811 unsigned int i, nblocks = 1;
812
813 if (locksz != 0) {
814 /* allocate 2 cache lines or at least one spinlock per cpu */
815 nblocks = max(2U * L1_CACHE_BYTES / locksz, 1U);
816 nblocks = roundup_pow_of_two(nblocks * num_possible_cpus());
817
818 /* no more locks than number of hash buckets */
819 nblocks = min(nblocks, hashinfo->ehash_mask + 1);
820
821 hashinfo->ehash_locks = kvmalloc_array(nblocks, locksz, GFP_KERNEL);
822 if (!hashinfo->ehash_locks)
823 return -ENOMEM;
824
825 for (i = 0; i < nblocks; i++)
826 spin_lock_init(&hashinfo->ehash_locks[i]);
827 }
828 hashinfo->ehash_locks_mask = nblocks - 1;
829 return 0;
830}
831EXPORT_SYMBOL_GPL(inet_ehash_locks_alloc);
832