2 * IPVS An implementation of the IP virtual server support for the
3 * LINUX operating system. IPVS is now implemented as a module
4 * over the Netfilter framework. IPVS can be used to build a
5 * high-performance and highly available server based on a
8 * Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
9 * Peter Kese <peter.kese@ijs.si>
10 * Julian Anastasov <ja@ssi.bg>
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
17 * The IPVS code for kernel 2.2 was done by Wensong Zhang and Peter Kese,
18 * with changes/fixes from Julian Anastasov, Lars Marowsky-Bree, Horms
19 * and others. Many code here is taken from IP MASQ code of kernel 2.2.
25 #define KMSG_COMPONENT "IPVS"
26 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
28 #include <linux/interrupt.h>
30 #include <linux/net.h>
31 #include <linux/kernel.h>
32 #include <linux/module.h>
33 #include <linux/vmalloc.h>
34 #include <linux/proc_fs.h> /* for proc_net_* */
35 #include <linux/slab.h>
36 #include <linux/seq_file.h>
37 #include <linux/jhash.h>
38 #include <linux/random.h>
40 #include <net/net_namespace.h>
41 #include <net/ip_vs.h>
44 #ifndef CONFIG_IP_VS_TAB_BITS
45 #define CONFIG_IP_VS_TAB_BITS 12
49 * Connection hash size. Default is what was selected at compile time.
51 int ip_vs_conn_tab_bits = CONFIG_IP_VS_TAB_BITS;
52 module_param_named(conn_tab_bits, ip_vs_conn_tab_bits, int, 0444);
53 MODULE_PARM_DESC(conn_tab_bits, "Set connections' hash size");
55 /* size and mask values */
56 int ip_vs_conn_tab_size;
57 int ip_vs_conn_tab_mask;
60 * Connection hash table: for input and output packets lookups of IPVS
62 static struct list_head *ip_vs_conn_tab;
64 /* SLAB cache for IPVS connections */
65 static struct kmem_cache *ip_vs_conn_cachep __read_mostly;
67 /* counter for current IPVS connections */
68 static atomic_t ip_vs_conn_count = ATOMIC_INIT(0);
70 /* counter for no client port connections */
71 static atomic_t ip_vs_conn_no_cport_cnt = ATOMIC_INIT(0);
73 /* random value for IPVS connection hash */
74 static unsigned int ip_vs_conn_rnd;
77 * Fine locking granularity for big connection hash table
79 #define CT_LOCKARRAY_BITS 4
80 #define CT_LOCKARRAY_SIZE (1<<CT_LOCKARRAY_BITS)
81 #define CT_LOCKARRAY_MASK (CT_LOCKARRAY_SIZE-1)
83 struct ip_vs_aligned_lock
86 } __attribute__((__aligned__(SMP_CACHE_BYTES)));
88 /* lock array for conn table */
89 static struct ip_vs_aligned_lock
90 __ip_vs_conntbl_lock_array[CT_LOCKARRAY_SIZE] __cacheline_aligned;
92 static inline void ct_read_lock(unsigned key)
94 read_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
97 static inline void ct_read_unlock(unsigned key)
99 read_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
102 static inline void ct_write_lock(unsigned key)
104 write_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
107 static inline void ct_write_unlock(unsigned key)
109 write_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
112 static inline void ct_read_lock_bh(unsigned key)
114 read_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
117 static inline void ct_read_unlock_bh(unsigned key)
119 read_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
122 static inline void ct_write_lock_bh(unsigned key)
124 write_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
127 static inline void ct_write_unlock_bh(unsigned key)
129 write_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
134 * Returns hash value for IPVS connection entry
136 static unsigned int ip_vs_conn_hashkey(int af, unsigned proto,
137 const union nf_inet_addr *addr,
140 #ifdef CONFIG_IP_VS_IPV6
142 return jhash_3words(jhash(addr, 16, ip_vs_conn_rnd),
143 (__force u32)port, proto, ip_vs_conn_rnd)
144 & ip_vs_conn_tab_mask;
146 return jhash_3words((__force u32)addr->ip, (__force u32)port, proto,
148 & ip_vs_conn_tab_mask;
153 * Hashes ip_vs_conn in ip_vs_conn_tab by proto,addr,port.
154 * returns bool success.
156 static inline int ip_vs_conn_hash(struct ip_vs_conn *cp)
161 /* Hash by protocol, client address and port */
162 hash = ip_vs_conn_hashkey(cp->af, cp->protocol, &cp->caddr, cp->cport);
166 if (!(cp->flags & IP_VS_CONN_F_HASHED)) {
167 list_add(&cp->c_list, &ip_vs_conn_tab[hash]);
168 cp->flags |= IP_VS_CONN_F_HASHED;
169 atomic_inc(&cp->refcnt);
172 pr_err("%s(): request for already hashed, called from %pF\n",
173 __func__, __builtin_return_address(0));
177 ct_write_unlock(hash);
184 * UNhashes ip_vs_conn from ip_vs_conn_tab.
185 * returns bool success.
187 static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp)
192 /* unhash it and decrease its reference counter */
193 hash = ip_vs_conn_hashkey(cp->af, cp->protocol, &cp->caddr, cp->cport);
197 if (cp->flags & IP_VS_CONN_F_HASHED) {
198 list_del(&cp->c_list);
199 cp->flags &= ~IP_VS_CONN_F_HASHED;
200 atomic_dec(&cp->refcnt);
205 ct_write_unlock(hash);
212 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
213 * Called for pkts coming from OUTside-to-INside.
214 * s_addr, s_port: pkt source address (foreign host)
215 * d_addr, d_port: pkt dest address (load balancer)
217 static inline struct ip_vs_conn *__ip_vs_conn_in_get
218 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
219 const union nf_inet_addr *d_addr, __be16 d_port)
222 struct ip_vs_conn *cp;
224 hash = ip_vs_conn_hashkey(af, protocol, s_addr, s_port);
228 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
230 ip_vs_addr_equal(af, s_addr, &cp->caddr) &&
231 ip_vs_addr_equal(af, d_addr, &cp->vaddr) &&
232 s_port == cp->cport && d_port == cp->vport &&
233 ((!s_port) ^ (!(cp->flags & IP_VS_CONN_F_NO_CPORT))) &&
234 protocol == cp->protocol) {
236 atomic_inc(&cp->refcnt);
237 ct_read_unlock(hash);
242 ct_read_unlock(hash);
247 struct ip_vs_conn *ip_vs_conn_in_get
248 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
249 const union nf_inet_addr *d_addr, __be16 d_port)
251 struct ip_vs_conn *cp;
253 cp = __ip_vs_conn_in_get(af, protocol, s_addr, s_port, d_addr, d_port);
254 if (!cp && atomic_read(&ip_vs_conn_no_cport_cnt))
255 cp = __ip_vs_conn_in_get(af, protocol, s_addr, 0, d_addr,
258 IP_VS_DBG_BUF(9, "lookup/in %s %s:%d->%s:%d %s\n",
259 ip_vs_proto_name(protocol),
260 IP_VS_DBG_ADDR(af, s_addr), ntohs(s_port),
261 IP_VS_DBG_ADDR(af, d_addr), ntohs(d_port),
262 cp ? "hit" : "not hit");
267 /* Get reference to connection template */
268 struct ip_vs_conn *ip_vs_ct_in_get
269 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
270 const union nf_inet_addr *d_addr, __be16 d_port)
273 struct ip_vs_conn *cp;
275 hash = ip_vs_conn_hashkey(af, protocol, s_addr, s_port);
279 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
281 ip_vs_addr_equal(af, s_addr, &cp->caddr) &&
282 /* protocol should only be IPPROTO_IP if
283 * d_addr is a fwmark */
284 ip_vs_addr_equal(protocol == IPPROTO_IP ? AF_UNSPEC : af,
285 d_addr, &cp->vaddr) &&
286 s_port == cp->cport && d_port == cp->vport &&
287 cp->flags & IP_VS_CONN_F_TEMPLATE &&
288 protocol == cp->protocol) {
290 atomic_inc(&cp->refcnt);
297 ct_read_unlock(hash);
299 IP_VS_DBG_BUF(9, "template lookup/in %s %s:%d->%s:%d %s\n",
300 ip_vs_proto_name(protocol),
301 IP_VS_DBG_ADDR(af, s_addr), ntohs(s_port),
302 IP_VS_DBG_ADDR(af, d_addr), ntohs(d_port),
303 cp ? "hit" : "not hit");
309 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
310 * Called for pkts coming from inside-to-OUTside.
311 * s_addr, s_port: pkt source address (inside host)
312 * d_addr, d_port: pkt dest address (foreign host)
314 struct ip_vs_conn *ip_vs_conn_out_get
315 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
316 const union nf_inet_addr *d_addr, __be16 d_port)
319 struct ip_vs_conn *cp, *ret=NULL;
322 * Check for "full" addressed entries
324 hash = ip_vs_conn_hashkey(af, protocol, d_addr, d_port);
328 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
330 ip_vs_addr_equal(af, d_addr, &cp->caddr) &&
331 ip_vs_addr_equal(af, s_addr, &cp->daddr) &&
332 d_port == cp->cport && s_port == cp->dport &&
333 protocol == cp->protocol) {
335 atomic_inc(&cp->refcnt);
341 ct_read_unlock(hash);
343 IP_VS_DBG_BUF(9, "lookup/out %s %s:%d->%s:%d %s\n",
344 ip_vs_proto_name(protocol),
345 IP_VS_DBG_ADDR(af, s_addr), ntohs(s_port),
346 IP_VS_DBG_ADDR(af, d_addr), ntohs(d_port),
347 ret ? "hit" : "not hit");
354 * Put back the conn and restart its timer with its timeout
356 void ip_vs_conn_put(struct ip_vs_conn *cp)
358 /* reset it expire in its timeout */
359 mod_timer(&cp->timer, jiffies+cp->timeout);
361 __ip_vs_conn_put(cp);
366 * Fill a no_client_port connection with a client port number
368 void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport)
370 if (ip_vs_conn_unhash(cp)) {
371 spin_lock(&cp->lock);
372 if (cp->flags & IP_VS_CONN_F_NO_CPORT) {
373 atomic_dec(&ip_vs_conn_no_cport_cnt);
374 cp->flags &= ~IP_VS_CONN_F_NO_CPORT;
377 spin_unlock(&cp->lock);
379 /* hash on new dport */
386 * Bind a connection entry with the corresponding packet_xmit.
387 * Called by ip_vs_conn_new.
389 static inline void ip_vs_bind_xmit(struct ip_vs_conn *cp)
391 switch (IP_VS_FWD_METHOD(cp)) {
392 case IP_VS_CONN_F_MASQ:
393 cp->packet_xmit = ip_vs_nat_xmit;
396 case IP_VS_CONN_F_TUNNEL:
397 cp->packet_xmit = ip_vs_tunnel_xmit;
400 case IP_VS_CONN_F_DROUTE:
401 cp->packet_xmit = ip_vs_dr_xmit;
404 case IP_VS_CONN_F_LOCALNODE:
405 cp->packet_xmit = ip_vs_null_xmit;
408 case IP_VS_CONN_F_BYPASS:
409 cp->packet_xmit = ip_vs_bypass_xmit;
414 #ifdef CONFIG_IP_VS_IPV6
415 static inline void ip_vs_bind_xmit_v6(struct ip_vs_conn *cp)
417 switch (IP_VS_FWD_METHOD(cp)) {
418 case IP_VS_CONN_F_MASQ:
419 cp->packet_xmit = ip_vs_nat_xmit_v6;
422 case IP_VS_CONN_F_TUNNEL:
423 cp->packet_xmit = ip_vs_tunnel_xmit_v6;
426 case IP_VS_CONN_F_DROUTE:
427 cp->packet_xmit = ip_vs_dr_xmit_v6;
430 case IP_VS_CONN_F_LOCALNODE:
431 cp->packet_xmit = ip_vs_null_xmit;
434 case IP_VS_CONN_F_BYPASS:
435 cp->packet_xmit = ip_vs_bypass_xmit_v6;
442 static inline int ip_vs_dest_totalconns(struct ip_vs_dest *dest)
444 return atomic_read(&dest->activeconns)
445 + atomic_read(&dest->inactconns);
449 * Bind a connection entry with a virtual service destination
450 * Called just after a new connection entry is created.
453 ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
455 /* if dest is NULL, then return directly */
459 /* Increase the refcnt counter of the dest */
460 atomic_inc(&dest->refcnt);
462 /* Bind with the destination and its corresponding transmitter */
463 if ((cp->flags & IP_VS_CONN_F_SYNC) &&
464 (!(cp->flags & IP_VS_CONN_F_TEMPLATE)))
465 /* if the connection is not template and is created
466 * by sync, preserve the activity flag.
468 cp->flags |= atomic_read(&dest->conn_flags) &
469 (~IP_VS_CONN_F_INACTIVE);
471 cp->flags |= atomic_read(&dest->conn_flags);
474 IP_VS_DBG_BUF(7, "Bind-dest %s c:%s:%d v:%s:%d "
475 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
477 ip_vs_proto_name(cp->protocol),
478 IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
479 IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
480 IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
481 ip_vs_fwd_tag(cp), cp->state,
482 cp->flags, atomic_read(&cp->refcnt),
483 atomic_read(&dest->refcnt));
485 /* Update the connection counters */
486 if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
487 /* It is a normal connection, so increase the inactive
488 connection counter because it is in TCP SYNRECV
489 state (inactive) or other protocol inacive state */
490 if ((cp->flags & IP_VS_CONN_F_SYNC) &&
491 (!(cp->flags & IP_VS_CONN_F_INACTIVE)))
492 atomic_inc(&dest->activeconns);
494 atomic_inc(&dest->inactconns);
496 /* It is a persistent connection/template, so increase
497 the peristent connection counter */
498 atomic_inc(&dest->persistconns);
501 if (dest->u_threshold != 0 &&
502 ip_vs_dest_totalconns(dest) >= dest->u_threshold)
503 dest->flags |= IP_VS_DEST_F_OVERLOAD;
508 * Check if there is a destination for the connection, if so
509 * bind the connection to the destination.
511 struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp)
513 struct ip_vs_dest *dest;
515 if ((cp) && (!cp->dest)) {
516 dest = ip_vs_find_dest(cp->af, &cp->daddr, cp->dport,
517 &cp->vaddr, cp->vport,
519 ip_vs_bind_dest(cp, dest);
527 * Unbind a connection entry with its VS destination
528 * Called by the ip_vs_conn_expire function.
530 static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp)
532 struct ip_vs_dest *dest = cp->dest;
537 IP_VS_DBG_BUF(7, "Unbind-dest %s c:%s:%d v:%s:%d "
538 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
540 ip_vs_proto_name(cp->protocol),
541 IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
542 IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
543 IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
544 ip_vs_fwd_tag(cp), cp->state,
545 cp->flags, atomic_read(&cp->refcnt),
546 atomic_read(&dest->refcnt));
548 /* Update the connection counters */
549 if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
550 /* It is a normal connection, so decrease the inactconns
551 or activeconns counter */
552 if (cp->flags & IP_VS_CONN_F_INACTIVE) {
553 atomic_dec(&dest->inactconns);
555 atomic_dec(&dest->activeconns);
558 /* It is a persistent connection/template, so decrease
559 the peristent connection counter */
560 atomic_dec(&dest->persistconns);
563 if (dest->l_threshold != 0) {
564 if (ip_vs_dest_totalconns(dest) < dest->l_threshold)
565 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
566 } else if (dest->u_threshold != 0) {
567 if (ip_vs_dest_totalconns(dest) * 4 < dest->u_threshold * 3)
568 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
570 if (dest->flags & IP_VS_DEST_F_OVERLOAD)
571 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
575 * Simply decrease the refcnt of the dest, because the
576 * dest will be either in service's destination list
579 atomic_dec(&dest->refcnt);
584 * Checking if the destination of a connection template is available.
585 * If available, return 1, otherwise invalidate this connection
586 * template and return 0.
588 int ip_vs_check_template(struct ip_vs_conn *ct)
590 struct ip_vs_dest *dest = ct->dest;
593 * Checking the dest server status.
595 if ((dest == NULL) ||
596 !(dest->flags & IP_VS_DEST_F_AVAILABLE) ||
597 (sysctl_ip_vs_expire_quiescent_template &&
598 (atomic_read(&dest->weight) == 0))) {
599 IP_VS_DBG_BUF(9, "check_template: dest not available for "
600 "protocol %s s:%s:%d v:%s:%d "
602 ip_vs_proto_name(ct->protocol),
603 IP_VS_DBG_ADDR(ct->af, &ct->caddr),
605 IP_VS_DBG_ADDR(ct->af, &ct->vaddr),
607 IP_VS_DBG_ADDR(ct->af, &ct->daddr),
611 * Invalidate the connection template
613 if (ct->vport != htons(0xffff)) {
614 if (ip_vs_conn_unhash(ct)) {
615 ct->dport = htons(0xffff);
616 ct->vport = htons(0xffff);
623 * Simply decrease the refcnt of the template,
624 * don't restart its timer.
626 atomic_dec(&ct->refcnt);
632 static void ip_vs_conn_expire(unsigned long data)
634 struct ip_vs_conn *cp = (struct ip_vs_conn *)data;
641 atomic_inc(&cp->refcnt);
644 * do I control anybody?
646 if (atomic_read(&cp->n_control))
650 * unhash it if it is hashed in the conn table
652 if (!ip_vs_conn_unhash(cp))
656 * refcnt==1 implies I'm the only one referrer
658 if (likely(atomic_read(&cp->refcnt) == 1)) {
659 /* delete the timer if it is activated by other users */
660 if (timer_pending(&cp->timer))
661 del_timer(&cp->timer);
663 /* does anybody control me? */
665 ip_vs_control_del(cp);
667 if (unlikely(cp->app != NULL))
668 ip_vs_unbind_app(cp);
669 ip_vs_unbind_dest(cp);
670 if (cp->flags & IP_VS_CONN_F_NO_CPORT)
671 atomic_dec(&ip_vs_conn_no_cport_cnt);
672 atomic_dec(&ip_vs_conn_count);
674 kmem_cache_free(ip_vs_conn_cachep, cp);
678 /* hash it back to the table */
682 IP_VS_DBG(7, "delayed: conn->refcnt-1=%d conn->n_control=%d\n",
683 atomic_read(&cp->refcnt)-1,
684 atomic_read(&cp->n_control));
690 void ip_vs_conn_expire_now(struct ip_vs_conn *cp)
692 if (del_timer(&cp->timer))
693 mod_timer(&cp->timer, jiffies);
698 * Create a new connection entry and hash it into the ip_vs_conn_tab
701 ip_vs_conn_new(int af, int proto, const union nf_inet_addr *caddr, __be16 cport,
702 const union nf_inet_addr *vaddr, __be16 vport,
703 const union nf_inet_addr *daddr, __be16 dport, unsigned flags,
704 struct ip_vs_dest *dest)
706 struct ip_vs_conn *cp;
707 struct ip_vs_protocol *pp = ip_vs_proto_get(proto);
709 cp = kmem_cache_zalloc(ip_vs_conn_cachep, GFP_ATOMIC);
711 IP_VS_ERR_RL("%s(): no memory\n", __func__);
715 INIT_LIST_HEAD(&cp->c_list);
716 setup_timer(&cp->timer, ip_vs_conn_expire, (unsigned long)cp);
718 cp->protocol = proto;
719 ip_vs_addr_copy(af, &cp->caddr, caddr);
721 ip_vs_addr_copy(af, &cp->vaddr, vaddr);
723 /* proto should only be IPPROTO_IP if d_addr is a fwmark */
724 ip_vs_addr_copy(proto == IPPROTO_IP ? AF_UNSPEC : af,
728 spin_lock_init(&cp->lock);
731 * Set the entry is referenced by the current thread before hashing
732 * it in the table, so that other thread run ip_vs_random_dropentry
733 * but cannot drop this entry.
735 atomic_set(&cp->refcnt, 1);
737 atomic_set(&cp->n_control, 0);
738 atomic_set(&cp->in_pkts, 0);
740 atomic_inc(&ip_vs_conn_count);
741 if (flags & IP_VS_CONN_F_NO_CPORT)
742 atomic_inc(&ip_vs_conn_no_cport_cnt);
744 /* Bind the connection with a destination server */
745 ip_vs_bind_dest(cp, dest);
747 /* Set its state and timeout */
751 /* Bind its packet transmitter */
752 #ifdef CONFIG_IP_VS_IPV6
754 ip_vs_bind_xmit_v6(cp);
759 if (unlikely(pp && atomic_read(&pp->appcnt)))
760 ip_vs_bind_app(cp, pp);
762 /* Hash it in the ip_vs_conn_tab finally */
770 * /proc/net/ip_vs_conn entries
772 #ifdef CONFIG_PROC_FS
774 static void *ip_vs_conn_array(struct seq_file *seq, loff_t pos)
777 struct ip_vs_conn *cp;
779 for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
780 ct_read_lock_bh(idx);
781 list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
783 seq->private = &ip_vs_conn_tab[idx];
787 ct_read_unlock_bh(idx);
793 static void *ip_vs_conn_seq_start(struct seq_file *seq, loff_t *pos)
796 return *pos ? ip_vs_conn_array(seq, *pos - 1) :SEQ_START_TOKEN;
799 static void *ip_vs_conn_seq_next(struct seq_file *seq, void *v, loff_t *pos)
801 struct ip_vs_conn *cp = v;
802 struct list_head *e, *l = seq->private;
806 if (v == SEQ_START_TOKEN)
807 return ip_vs_conn_array(seq, 0);
809 /* more on same hash chain? */
810 if ((e = cp->c_list.next) != l)
811 return list_entry(e, struct ip_vs_conn, c_list);
813 idx = l - ip_vs_conn_tab;
814 ct_read_unlock_bh(idx);
816 while (++idx < ip_vs_conn_tab_size) {
817 ct_read_lock_bh(idx);
818 list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
819 seq->private = &ip_vs_conn_tab[idx];
822 ct_read_unlock_bh(idx);
828 static void ip_vs_conn_seq_stop(struct seq_file *seq, void *v)
830 struct list_head *l = seq->private;
833 ct_read_unlock_bh(l - ip_vs_conn_tab);
836 static int ip_vs_conn_seq_show(struct seq_file *seq, void *v)
839 if (v == SEQ_START_TOKEN)
841 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Expires\n");
843 const struct ip_vs_conn *cp = v;
845 #ifdef CONFIG_IP_VS_IPV6
846 if (cp->af == AF_INET6)
847 seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %7lu\n",
848 ip_vs_proto_name(cp->protocol),
849 &cp->caddr.in6, ntohs(cp->cport),
850 &cp->vaddr.in6, ntohs(cp->vport),
851 &cp->daddr.in6, ntohs(cp->dport),
852 ip_vs_state_name(cp->protocol, cp->state),
853 (cp->timer.expires-jiffies)/HZ);
857 "%-3s %08X %04X %08X %04X"
858 " %08X %04X %-11s %7lu\n",
859 ip_vs_proto_name(cp->protocol),
860 ntohl(cp->caddr.ip), ntohs(cp->cport),
861 ntohl(cp->vaddr.ip), ntohs(cp->vport),
862 ntohl(cp->daddr.ip), ntohs(cp->dport),
863 ip_vs_state_name(cp->protocol, cp->state),
864 (cp->timer.expires-jiffies)/HZ);
869 static const struct seq_operations ip_vs_conn_seq_ops = {
870 .start = ip_vs_conn_seq_start,
871 .next = ip_vs_conn_seq_next,
872 .stop = ip_vs_conn_seq_stop,
873 .show = ip_vs_conn_seq_show,
876 static int ip_vs_conn_open(struct inode *inode, struct file *file)
878 return seq_open(file, &ip_vs_conn_seq_ops);
881 static const struct file_operations ip_vs_conn_fops = {
882 .owner = THIS_MODULE,
883 .open = ip_vs_conn_open,
886 .release = seq_release,
889 static const char *ip_vs_origin_name(unsigned flags)
891 if (flags & IP_VS_CONN_F_SYNC)
897 static int ip_vs_conn_sync_seq_show(struct seq_file *seq, void *v)
900 if (v == SEQ_START_TOKEN)
902 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Origin Expires\n");
904 const struct ip_vs_conn *cp = v;
906 #ifdef CONFIG_IP_VS_IPV6
907 if (cp->af == AF_INET6)
908 seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %-6s %7lu\n",
909 ip_vs_proto_name(cp->protocol),
910 &cp->caddr.in6, ntohs(cp->cport),
911 &cp->vaddr.in6, ntohs(cp->vport),
912 &cp->daddr.in6, ntohs(cp->dport),
913 ip_vs_state_name(cp->protocol, cp->state),
914 ip_vs_origin_name(cp->flags),
915 (cp->timer.expires-jiffies)/HZ);
919 "%-3s %08X %04X %08X %04X "
920 "%08X %04X %-11s %-6s %7lu\n",
921 ip_vs_proto_name(cp->protocol),
922 ntohl(cp->caddr.ip), ntohs(cp->cport),
923 ntohl(cp->vaddr.ip), ntohs(cp->vport),
924 ntohl(cp->daddr.ip), ntohs(cp->dport),
925 ip_vs_state_name(cp->protocol, cp->state),
926 ip_vs_origin_name(cp->flags),
927 (cp->timer.expires-jiffies)/HZ);
932 static const struct seq_operations ip_vs_conn_sync_seq_ops = {
933 .start = ip_vs_conn_seq_start,
934 .next = ip_vs_conn_seq_next,
935 .stop = ip_vs_conn_seq_stop,
936 .show = ip_vs_conn_sync_seq_show,
939 static int ip_vs_conn_sync_open(struct inode *inode, struct file *file)
941 return seq_open(file, &ip_vs_conn_sync_seq_ops);
944 static const struct file_operations ip_vs_conn_sync_fops = {
945 .owner = THIS_MODULE,
946 .open = ip_vs_conn_sync_open,
949 .release = seq_release,
956 * Randomly drop connection entries before running out of memory
958 static inline int todrop_entry(struct ip_vs_conn *cp)
961 * The drop rate array needs tuning for real environments.
962 * Called from timer bh only => no locking
964 static const char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
965 static char todrop_counter[9] = {0};
968 /* if the conn entry hasn't lasted for 60 seconds, don't drop it.
969 This will leave enough time for normal connection to get
971 if (time_before(cp->timeout + jiffies, cp->timer.expires + 60*HZ))
974 /* Don't drop the entry if its number of incoming packets is not
976 i = atomic_read(&cp->in_pkts);
977 if (i > 8 || i < 0) return 0;
979 if (!todrop_rate[i]) return 0;
980 if (--todrop_counter[i] > 0) return 0;
982 todrop_counter[i] = todrop_rate[i];
986 /* Called from keventd and must protect itself from softirqs */
987 void ip_vs_random_dropentry(void)
990 struct ip_vs_conn *cp;
993 * Randomly scan 1/32 of the whole table every second
995 for (idx = 0; idx < (ip_vs_conn_tab_size>>5); idx++) {
996 unsigned hash = net_random() & ip_vs_conn_tab_mask;
999 * Lock is actually needed in this loop.
1001 ct_write_lock_bh(hash);
1003 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
1004 if (cp->flags & IP_VS_CONN_F_TEMPLATE)
1005 /* connection template */
1008 if (cp->protocol == IPPROTO_TCP) {
1010 case IP_VS_TCP_S_SYN_RECV:
1011 case IP_VS_TCP_S_SYNACK:
1014 case IP_VS_TCP_S_ESTABLISHED:
1015 if (todrop_entry(cp))
1023 if (!todrop_entry(cp))
1027 IP_VS_DBG(4, "del connection\n");
1028 ip_vs_conn_expire_now(cp);
1030 IP_VS_DBG(4, "del conn template\n");
1031 ip_vs_conn_expire_now(cp->control);
1034 ct_write_unlock_bh(hash);
1040 * Flush all the connection entries in the ip_vs_conn_tab
1042 static void ip_vs_conn_flush(void)
1045 struct ip_vs_conn *cp;
1048 for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
1050 * Lock is actually needed in this loop.
1052 ct_write_lock_bh(idx);
1054 list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
1056 IP_VS_DBG(4, "del connection\n");
1057 ip_vs_conn_expire_now(cp);
1059 IP_VS_DBG(4, "del conn template\n");
1060 ip_vs_conn_expire_now(cp->control);
1063 ct_write_unlock_bh(idx);
1066 /* the counter may be not NULL, because maybe some conn entries
1067 are run by slow timer handler or unhashed but still referred */
1068 if (atomic_read(&ip_vs_conn_count) != 0) {
1075 int __init ip_vs_conn_init(void)
1079 /* Compute size and mask */
1080 ip_vs_conn_tab_size = 1 << ip_vs_conn_tab_bits;
1081 ip_vs_conn_tab_mask = ip_vs_conn_tab_size - 1;
1084 * Allocate the connection hash table and initialize its list heads
1086 ip_vs_conn_tab = vmalloc(ip_vs_conn_tab_size *
1087 sizeof(struct list_head));
1088 if (!ip_vs_conn_tab)
1091 /* Allocate ip_vs_conn slab cache */
1092 ip_vs_conn_cachep = kmem_cache_create("ip_vs_conn",
1093 sizeof(struct ip_vs_conn), 0,
1094 SLAB_HWCACHE_ALIGN, NULL);
1095 if (!ip_vs_conn_cachep) {
1096 vfree(ip_vs_conn_tab);
1100 pr_info("Connection hash table configured "
1101 "(size=%d, memory=%ldKbytes)\n",
1102 ip_vs_conn_tab_size,
1103 (long)(ip_vs_conn_tab_size*sizeof(struct list_head))/1024);
1104 IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n",
1105 sizeof(struct ip_vs_conn));
1107 for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
1108 INIT_LIST_HEAD(&ip_vs_conn_tab[idx]);
1111 for (idx = 0; idx < CT_LOCKARRAY_SIZE; idx++) {
1112 rwlock_init(&__ip_vs_conntbl_lock_array[idx].l);
1115 proc_net_fops_create(&init_net, "ip_vs_conn", 0, &ip_vs_conn_fops);
1116 proc_net_fops_create(&init_net, "ip_vs_conn_sync", 0, &ip_vs_conn_sync_fops);
1118 /* calculate the random value for connection hash */
1119 get_random_bytes(&ip_vs_conn_rnd, sizeof(ip_vs_conn_rnd));
1125 void ip_vs_conn_cleanup(void)
1127 /* flush all the connection entries first */
1130 /* Release the empty cache */
1131 kmem_cache_destroy(ip_vs_conn_cachep);
1132 proc_net_remove(&init_net, "ip_vs_conn");
1133 proc_net_remove(&init_net, "ip_vs_conn_sync");
1134 vfree(ip_vs_conn_tab);