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);
165 spin_lock(&cp->lock);
167 if (!(cp->flags & IP_VS_CONN_F_HASHED)) {
168 list_add(&cp->c_list, &ip_vs_conn_tab[hash]);
169 cp->flags |= IP_VS_CONN_F_HASHED;
170 atomic_inc(&cp->refcnt);
173 pr_err("%s(): request for already hashed, called from %pF\n",
174 __func__, __builtin_return_address(0));
178 spin_unlock(&cp->lock);
179 ct_write_unlock(hash);
186 * UNhashes ip_vs_conn from ip_vs_conn_tab.
187 * returns bool success.
189 static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp)
194 /* unhash it and decrease its reference counter */
195 hash = ip_vs_conn_hashkey(cp->af, cp->protocol, &cp->caddr, cp->cport);
198 spin_lock(&cp->lock);
200 if (cp->flags & IP_VS_CONN_F_HASHED) {
201 list_del(&cp->c_list);
202 cp->flags &= ~IP_VS_CONN_F_HASHED;
203 atomic_dec(&cp->refcnt);
208 spin_unlock(&cp->lock);
209 ct_write_unlock(hash);
216 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
217 * Called for pkts coming from OUTside-to-INside.
218 * s_addr, s_port: pkt source address (foreign host)
219 * d_addr, d_port: pkt dest address (load balancer)
221 static inline struct ip_vs_conn *__ip_vs_conn_in_get
222 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
223 const union nf_inet_addr *d_addr, __be16 d_port)
226 struct ip_vs_conn *cp;
228 hash = ip_vs_conn_hashkey(af, protocol, s_addr, s_port);
232 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
234 ip_vs_addr_equal(af, s_addr, &cp->caddr) &&
235 ip_vs_addr_equal(af, d_addr, &cp->vaddr) &&
236 s_port == cp->cport && d_port == cp->vport &&
237 ((!s_port) ^ (!(cp->flags & IP_VS_CONN_F_NO_CPORT))) &&
238 protocol == cp->protocol) {
240 atomic_inc(&cp->refcnt);
241 ct_read_unlock(hash);
246 ct_read_unlock(hash);
251 struct ip_vs_conn *ip_vs_conn_in_get
252 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
253 const union nf_inet_addr *d_addr, __be16 d_port)
255 struct ip_vs_conn *cp;
257 cp = __ip_vs_conn_in_get(af, protocol, s_addr, s_port, d_addr, d_port);
258 if (!cp && atomic_read(&ip_vs_conn_no_cport_cnt))
259 cp = __ip_vs_conn_in_get(af, protocol, s_addr, 0, d_addr,
262 IP_VS_DBG_BUF(9, "lookup/in %s %s:%d->%s:%d %s\n",
263 ip_vs_proto_name(protocol),
264 IP_VS_DBG_ADDR(af, s_addr), ntohs(s_port),
265 IP_VS_DBG_ADDR(af, d_addr), ntohs(d_port),
266 cp ? "hit" : "not hit");
271 /* Get reference to connection template */
272 struct ip_vs_conn *ip_vs_ct_in_get
273 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
274 const union nf_inet_addr *d_addr, __be16 d_port)
277 struct ip_vs_conn *cp;
279 hash = ip_vs_conn_hashkey(af, protocol, s_addr, s_port);
283 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
285 ip_vs_addr_equal(af, s_addr, &cp->caddr) &&
286 /* protocol should only be IPPROTO_IP if
287 * d_addr is a fwmark */
288 ip_vs_addr_equal(protocol == IPPROTO_IP ? AF_UNSPEC : af,
289 d_addr, &cp->vaddr) &&
290 s_port == cp->cport && d_port == cp->vport &&
291 cp->flags & IP_VS_CONN_F_TEMPLATE &&
292 protocol == cp->protocol) {
294 atomic_inc(&cp->refcnt);
301 ct_read_unlock(hash);
303 IP_VS_DBG_BUF(9, "template lookup/in %s %s:%d->%s:%d %s\n",
304 ip_vs_proto_name(protocol),
305 IP_VS_DBG_ADDR(af, s_addr), ntohs(s_port),
306 IP_VS_DBG_ADDR(af, d_addr), ntohs(d_port),
307 cp ? "hit" : "not hit");
313 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
314 * Called for pkts coming from inside-to-OUTside.
315 * s_addr, s_port: pkt source address (inside host)
316 * d_addr, d_port: pkt dest address (foreign host)
318 struct ip_vs_conn *ip_vs_conn_out_get
319 (int af, int protocol, const union nf_inet_addr *s_addr, __be16 s_port,
320 const union nf_inet_addr *d_addr, __be16 d_port)
323 struct ip_vs_conn *cp, *ret=NULL;
326 * Check for "full" addressed entries
328 hash = ip_vs_conn_hashkey(af, protocol, d_addr, d_port);
332 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
334 ip_vs_addr_equal(af, d_addr, &cp->caddr) &&
335 ip_vs_addr_equal(af, s_addr, &cp->daddr) &&
336 d_port == cp->cport && s_port == cp->dport &&
337 protocol == cp->protocol) {
339 atomic_inc(&cp->refcnt);
345 ct_read_unlock(hash);
347 IP_VS_DBG_BUF(9, "lookup/out %s %s:%d->%s:%d %s\n",
348 ip_vs_proto_name(protocol),
349 IP_VS_DBG_ADDR(af, s_addr), ntohs(s_port),
350 IP_VS_DBG_ADDR(af, d_addr), ntohs(d_port),
351 ret ? "hit" : "not hit");
358 * Put back the conn and restart its timer with its timeout
360 void ip_vs_conn_put(struct ip_vs_conn *cp)
362 /* reset it expire in its timeout */
363 mod_timer(&cp->timer, jiffies+cp->timeout);
365 __ip_vs_conn_put(cp);
370 * Fill a no_client_port connection with a client port number
372 void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport)
374 if (ip_vs_conn_unhash(cp)) {
375 spin_lock(&cp->lock);
376 if (cp->flags & IP_VS_CONN_F_NO_CPORT) {
377 atomic_dec(&ip_vs_conn_no_cport_cnt);
378 cp->flags &= ~IP_VS_CONN_F_NO_CPORT;
381 spin_unlock(&cp->lock);
383 /* hash on new dport */
390 * Bind a connection entry with the corresponding packet_xmit.
391 * Called by ip_vs_conn_new.
393 static inline void ip_vs_bind_xmit(struct ip_vs_conn *cp)
395 switch (IP_VS_FWD_METHOD(cp)) {
396 case IP_VS_CONN_F_MASQ:
397 cp->packet_xmit = ip_vs_nat_xmit;
400 case IP_VS_CONN_F_TUNNEL:
401 cp->packet_xmit = ip_vs_tunnel_xmit;
404 case IP_VS_CONN_F_DROUTE:
405 cp->packet_xmit = ip_vs_dr_xmit;
408 case IP_VS_CONN_F_LOCALNODE:
409 cp->packet_xmit = ip_vs_null_xmit;
412 case IP_VS_CONN_F_BYPASS:
413 cp->packet_xmit = ip_vs_bypass_xmit;
418 #ifdef CONFIG_IP_VS_IPV6
419 static inline void ip_vs_bind_xmit_v6(struct ip_vs_conn *cp)
421 switch (IP_VS_FWD_METHOD(cp)) {
422 case IP_VS_CONN_F_MASQ:
423 cp->packet_xmit = ip_vs_nat_xmit_v6;
426 case IP_VS_CONN_F_TUNNEL:
427 cp->packet_xmit = ip_vs_tunnel_xmit_v6;
430 case IP_VS_CONN_F_DROUTE:
431 cp->packet_xmit = ip_vs_dr_xmit_v6;
434 case IP_VS_CONN_F_LOCALNODE:
435 cp->packet_xmit = ip_vs_null_xmit;
438 case IP_VS_CONN_F_BYPASS:
439 cp->packet_xmit = ip_vs_bypass_xmit_v6;
446 static inline int ip_vs_dest_totalconns(struct ip_vs_dest *dest)
448 return atomic_read(&dest->activeconns)
449 + atomic_read(&dest->inactconns);
453 * Bind a connection entry with a virtual service destination
454 * Called just after a new connection entry is created.
457 ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
459 /* if dest is NULL, then return directly */
463 /* Increase the refcnt counter of the dest */
464 atomic_inc(&dest->refcnt);
466 /* Bind with the destination and its corresponding transmitter */
467 if ((cp->flags & IP_VS_CONN_F_SYNC) &&
468 (!(cp->flags & IP_VS_CONN_F_TEMPLATE)))
469 /* if the connection is not template and is created
470 * by sync, preserve the activity flag.
472 cp->flags |= atomic_read(&dest->conn_flags) &
473 (~IP_VS_CONN_F_INACTIVE);
475 cp->flags |= atomic_read(&dest->conn_flags);
478 IP_VS_DBG_BUF(7, "Bind-dest %s c:%s:%d v:%s:%d "
479 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
481 ip_vs_proto_name(cp->protocol),
482 IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
483 IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
484 IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
485 ip_vs_fwd_tag(cp), cp->state,
486 cp->flags, atomic_read(&cp->refcnt),
487 atomic_read(&dest->refcnt));
489 /* Update the connection counters */
490 if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
491 /* It is a normal connection, so increase the inactive
492 connection counter because it is in TCP SYNRECV
493 state (inactive) or other protocol inacive state */
494 if ((cp->flags & IP_VS_CONN_F_SYNC) &&
495 (!(cp->flags & IP_VS_CONN_F_INACTIVE)))
496 atomic_inc(&dest->activeconns);
498 atomic_inc(&dest->inactconns);
500 /* It is a persistent connection/template, so increase
501 the peristent connection counter */
502 atomic_inc(&dest->persistconns);
505 if (dest->u_threshold != 0 &&
506 ip_vs_dest_totalconns(dest) >= dest->u_threshold)
507 dest->flags |= IP_VS_DEST_F_OVERLOAD;
512 * Check if there is a destination for the connection, if so
513 * bind the connection to the destination.
515 struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp)
517 struct ip_vs_dest *dest;
519 if ((cp) && (!cp->dest)) {
520 dest = ip_vs_find_dest(cp->af, &cp->daddr, cp->dport,
521 &cp->vaddr, cp->vport,
523 ip_vs_bind_dest(cp, dest);
531 * Unbind a connection entry with its VS destination
532 * Called by the ip_vs_conn_expire function.
534 static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp)
536 struct ip_vs_dest *dest = cp->dest;
541 IP_VS_DBG_BUF(7, "Unbind-dest %s c:%s:%d v:%s:%d "
542 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
544 ip_vs_proto_name(cp->protocol),
545 IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
546 IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
547 IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
548 ip_vs_fwd_tag(cp), cp->state,
549 cp->flags, atomic_read(&cp->refcnt),
550 atomic_read(&dest->refcnt));
552 /* Update the connection counters */
553 if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
554 /* It is a normal connection, so decrease the inactconns
555 or activeconns counter */
556 if (cp->flags & IP_VS_CONN_F_INACTIVE) {
557 atomic_dec(&dest->inactconns);
559 atomic_dec(&dest->activeconns);
562 /* It is a persistent connection/template, so decrease
563 the peristent connection counter */
564 atomic_dec(&dest->persistconns);
567 if (dest->l_threshold != 0) {
568 if (ip_vs_dest_totalconns(dest) < dest->l_threshold)
569 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
570 } else if (dest->u_threshold != 0) {
571 if (ip_vs_dest_totalconns(dest) * 4 < dest->u_threshold * 3)
572 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
574 if (dest->flags & IP_VS_DEST_F_OVERLOAD)
575 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
579 * Simply decrease the refcnt of the dest, because the
580 * dest will be either in service's destination list
583 atomic_dec(&dest->refcnt);
588 * Checking if the destination of a connection template is available.
589 * If available, return 1, otherwise invalidate this connection
590 * template and return 0.
592 int ip_vs_check_template(struct ip_vs_conn *ct)
594 struct ip_vs_dest *dest = ct->dest;
597 * Checking the dest server status.
599 if ((dest == NULL) ||
600 !(dest->flags & IP_VS_DEST_F_AVAILABLE) ||
601 (sysctl_ip_vs_expire_quiescent_template &&
602 (atomic_read(&dest->weight) == 0))) {
603 IP_VS_DBG_BUF(9, "check_template: dest not available for "
604 "protocol %s s:%s:%d v:%s:%d "
606 ip_vs_proto_name(ct->protocol),
607 IP_VS_DBG_ADDR(ct->af, &ct->caddr),
609 IP_VS_DBG_ADDR(ct->af, &ct->vaddr),
611 IP_VS_DBG_ADDR(ct->af, &ct->daddr),
615 * Invalidate the connection template
617 if (ct->vport != htons(0xffff)) {
618 if (ip_vs_conn_unhash(ct)) {
619 ct->dport = htons(0xffff);
620 ct->vport = htons(0xffff);
627 * Simply decrease the refcnt of the template,
628 * don't restart its timer.
630 atomic_dec(&ct->refcnt);
636 static void ip_vs_conn_expire(unsigned long data)
638 struct ip_vs_conn *cp = (struct ip_vs_conn *)data;
645 atomic_inc(&cp->refcnt);
648 * do I control anybody?
650 if (atomic_read(&cp->n_control))
654 * unhash it if it is hashed in the conn table
656 if (!ip_vs_conn_unhash(cp))
660 * refcnt==1 implies I'm the only one referrer
662 if (likely(atomic_read(&cp->refcnt) == 1)) {
663 /* delete the timer if it is activated by other users */
664 if (timer_pending(&cp->timer))
665 del_timer(&cp->timer);
667 /* does anybody control me? */
669 ip_vs_control_del(cp);
671 if (unlikely(cp->app != NULL))
672 ip_vs_unbind_app(cp);
673 ip_vs_unbind_dest(cp);
674 if (cp->flags & IP_VS_CONN_F_NO_CPORT)
675 atomic_dec(&ip_vs_conn_no_cport_cnt);
676 atomic_dec(&ip_vs_conn_count);
678 kmem_cache_free(ip_vs_conn_cachep, cp);
682 /* hash it back to the table */
686 IP_VS_DBG(7, "delayed: conn->refcnt-1=%d conn->n_control=%d\n",
687 atomic_read(&cp->refcnt)-1,
688 atomic_read(&cp->n_control));
694 void ip_vs_conn_expire_now(struct ip_vs_conn *cp)
696 if (del_timer(&cp->timer))
697 mod_timer(&cp->timer, jiffies);
702 * Create a new connection entry and hash it into the ip_vs_conn_tab
705 ip_vs_conn_new(int af, int proto, const union nf_inet_addr *caddr, __be16 cport,
706 const union nf_inet_addr *vaddr, __be16 vport,
707 const union nf_inet_addr *daddr, __be16 dport, unsigned flags,
708 struct ip_vs_dest *dest)
710 struct ip_vs_conn *cp;
711 struct ip_vs_protocol *pp = ip_vs_proto_get(proto);
713 cp = kmem_cache_zalloc(ip_vs_conn_cachep, GFP_ATOMIC);
715 IP_VS_ERR_RL("%s(): no memory\n", __func__);
719 INIT_LIST_HEAD(&cp->c_list);
720 setup_timer(&cp->timer, ip_vs_conn_expire, (unsigned long)cp);
722 cp->protocol = proto;
723 ip_vs_addr_copy(af, &cp->caddr, caddr);
725 ip_vs_addr_copy(af, &cp->vaddr, vaddr);
727 /* proto should only be IPPROTO_IP if d_addr is a fwmark */
728 ip_vs_addr_copy(proto == IPPROTO_IP ? AF_UNSPEC : af,
732 spin_lock_init(&cp->lock);
735 * Set the entry is referenced by the current thread before hashing
736 * it in the table, so that other thread run ip_vs_random_dropentry
737 * but cannot drop this entry.
739 atomic_set(&cp->refcnt, 1);
741 atomic_set(&cp->n_control, 0);
742 atomic_set(&cp->in_pkts, 0);
744 atomic_inc(&ip_vs_conn_count);
745 if (flags & IP_VS_CONN_F_NO_CPORT)
746 atomic_inc(&ip_vs_conn_no_cport_cnt);
748 /* Bind the connection with a destination server */
749 ip_vs_bind_dest(cp, dest);
751 /* Set its state and timeout */
755 /* Bind its packet transmitter */
756 #ifdef CONFIG_IP_VS_IPV6
758 ip_vs_bind_xmit_v6(cp);
763 if (unlikely(pp && atomic_read(&pp->appcnt)))
764 ip_vs_bind_app(cp, pp);
766 /* Hash it in the ip_vs_conn_tab finally */
774 * /proc/net/ip_vs_conn entries
776 #ifdef CONFIG_PROC_FS
778 static void *ip_vs_conn_array(struct seq_file *seq, loff_t pos)
781 struct ip_vs_conn *cp;
783 for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
784 ct_read_lock_bh(idx);
785 list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
787 seq->private = &ip_vs_conn_tab[idx];
791 ct_read_unlock_bh(idx);
797 static void *ip_vs_conn_seq_start(struct seq_file *seq, loff_t *pos)
800 return *pos ? ip_vs_conn_array(seq, *pos - 1) :SEQ_START_TOKEN;
803 static void *ip_vs_conn_seq_next(struct seq_file *seq, void *v, loff_t *pos)
805 struct ip_vs_conn *cp = v;
806 struct list_head *e, *l = seq->private;
810 if (v == SEQ_START_TOKEN)
811 return ip_vs_conn_array(seq, 0);
813 /* more on same hash chain? */
814 if ((e = cp->c_list.next) != l)
815 return list_entry(e, struct ip_vs_conn, c_list);
817 idx = l - ip_vs_conn_tab;
818 ct_read_unlock_bh(idx);
820 while (++idx < ip_vs_conn_tab_size) {
821 ct_read_lock_bh(idx);
822 list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
823 seq->private = &ip_vs_conn_tab[idx];
826 ct_read_unlock_bh(idx);
832 static void ip_vs_conn_seq_stop(struct seq_file *seq, void *v)
834 struct list_head *l = seq->private;
837 ct_read_unlock_bh(l - ip_vs_conn_tab);
840 static int ip_vs_conn_seq_show(struct seq_file *seq, void *v)
843 if (v == SEQ_START_TOKEN)
845 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Expires\n");
847 const struct ip_vs_conn *cp = v;
849 #ifdef CONFIG_IP_VS_IPV6
850 if (cp->af == AF_INET6)
851 seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %7lu\n",
852 ip_vs_proto_name(cp->protocol),
853 &cp->caddr.in6, ntohs(cp->cport),
854 &cp->vaddr.in6, ntohs(cp->vport),
855 &cp->daddr.in6, ntohs(cp->dport),
856 ip_vs_state_name(cp->protocol, cp->state),
857 (cp->timer.expires-jiffies)/HZ);
861 "%-3s %08X %04X %08X %04X"
862 " %08X %04X %-11s %7lu\n",
863 ip_vs_proto_name(cp->protocol),
864 ntohl(cp->caddr.ip), ntohs(cp->cport),
865 ntohl(cp->vaddr.ip), ntohs(cp->vport),
866 ntohl(cp->daddr.ip), ntohs(cp->dport),
867 ip_vs_state_name(cp->protocol, cp->state),
868 (cp->timer.expires-jiffies)/HZ);
873 static const struct seq_operations ip_vs_conn_seq_ops = {
874 .start = ip_vs_conn_seq_start,
875 .next = ip_vs_conn_seq_next,
876 .stop = ip_vs_conn_seq_stop,
877 .show = ip_vs_conn_seq_show,
880 static int ip_vs_conn_open(struct inode *inode, struct file *file)
882 return seq_open(file, &ip_vs_conn_seq_ops);
885 static const struct file_operations ip_vs_conn_fops = {
886 .owner = THIS_MODULE,
887 .open = ip_vs_conn_open,
890 .release = seq_release,
893 static const char *ip_vs_origin_name(unsigned flags)
895 if (flags & IP_VS_CONN_F_SYNC)
901 static int ip_vs_conn_sync_seq_show(struct seq_file *seq, void *v)
904 if (v == SEQ_START_TOKEN)
906 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Origin Expires\n");
908 const struct ip_vs_conn *cp = v;
910 #ifdef CONFIG_IP_VS_IPV6
911 if (cp->af == AF_INET6)
912 seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %-6s %7lu\n",
913 ip_vs_proto_name(cp->protocol),
914 &cp->caddr.in6, ntohs(cp->cport),
915 &cp->vaddr.in6, ntohs(cp->vport),
916 &cp->daddr.in6, ntohs(cp->dport),
917 ip_vs_state_name(cp->protocol, cp->state),
918 ip_vs_origin_name(cp->flags),
919 (cp->timer.expires-jiffies)/HZ);
923 "%-3s %08X %04X %08X %04X "
924 "%08X %04X %-11s %-6s %7lu\n",
925 ip_vs_proto_name(cp->protocol),
926 ntohl(cp->caddr.ip), ntohs(cp->cport),
927 ntohl(cp->vaddr.ip), ntohs(cp->vport),
928 ntohl(cp->daddr.ip), ntohs(cp->dport),
929 ip_vs_state_name(cp->protocol, cp->state),
930 ip_vs_origin_name(cp->flags),
931 (cp->timer.expires-jiffies)/HZ);
936 static const struct seq_operations ip_vs_conn_sync_seq_ops = {
937 .start = ip_vs_conn_seq_start,
938 .next = ip_vs_conn_seq_next,
939 .stop = ip_vs_conn_seq_stop,
940 .show = ip_vs_conn_sync_seq_show,
943 static int ip_vs_conn_sync_open(struct inode *inode, struct file *file)
945 return seq_open(file, &ip_vs_conn_sync_seq_ops);
948 static const struct file_operations ip_vs_conn_sync_fops = {
949 .owner = THIS_MODULE,
950 .open = ip_vs_conn_sync_open,
953 .release = seq_release,
960 * Randomly drop connection entries before running out of memory
962 static inline int todrop_entry(struct ip_vs_conn *cp)
965 * The drop rate array needs tuning for real environments.
966 * Called from timer bh only => no locking
968 static const char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
969 static char todrop_counter[9] = {0};
972 /* if the conn entry hasn't lasted for 60 seconds, don't drop it.
973 This will leave enough time for normal connection to get
975 if (time_before(cp->timeout + jiffies, cp->timer.expires + 60*HZ))
978 /* Don't drop the entry if its number of incoming packets is not
980 i = atomic_read(&cp->in_pkts);
981 if (i > 8 || i < 0) return 0;
983 if (!todrop_rate[i]) return 0;
984 if (--todrop_counter[i] > 0) return 0;
986 todrop_counter[i] = todrop_rate[i];
990 /* Called from keventd and must protect itself from softirqs */
991 void ip_vs_random_dropentry(void)
994 struct ip_vs_conn *cp;
997 * Randomly scan 1/32 of the whole table every second
999 for (idx = 0; idx < (ip_vs_conn_tab_size>>5); idx++) {
1000 unsigned hash = net_random() & ip_vs_conn_tab_mask;
1003 * Lock is actually needed in this loop.
1005 ct_write_lock_bh(hash);
1007 list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
1008 if (cp->flags & IP_VS_CONN_F_TEMPLATE)
1009 /* connection template */
1012 if (cp->protocol == IPPROTO_TCP) {
1014 case IP_VS_TCP_S_SYN_RECV:
1015 case IP_VS_TCP_S_SYNACK:
1018 case IP_VS_TCP_S_ESTABLISHED:
1019 if (todrop_entry(cp))
1027 if (!todrop_entry(cp))
1031 IP_VS_DBG(4, "del connection\n");
1032 ip_vs_conn_expire_now(cp);
1034 IP_VS_DBG(4, "del conn template\n");
1035 ip_vs_conn_expire_now(cp->control);
1038 ct_write_unlock_bh(hash);
1044 * Flush all the connection entries in the ip_vs_conn_tab
1046 static void ip_vs_conn_flush(void)
1049 struct ip_vs_conn *cp;
1052 for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
1054 * Lock is actually needed in this loop.
1056 ct_write_lock_bh(idx);
1058 list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
1060 IP_VS_DBG(4, "del connection\n");
1061 ip_vs_conn_expire_now(cp);
1063 IP_VS_DBG(4, "del conn template\n");
1064 ip_vs_conn_expire_now(cp->control);
1067 ct_write_unlock_bh(idx);
1070 /* the counter may be not NULL, because maybe some conn entries
1071 are run by slow timer handler or unhashed but still referred */
1072 if (atomic_read(&ip_vs_conn_count) != 0) {
1079 int __init ip_vs_conn_init(void)
1083 /* Compute size and mask */
1084 ip_vs_conn_tab_size = 1 << ip_vs_conn_tab_bits;
1085 ip_vs_conn_tab_mask = ip_vs_conn_tab_size - 1;
1088 * Allocate the connection hash table and initialize its list heads
1090 ip_vs_conn_tab = vmalloc(ip_vs_conn_tab_size *
1091 sizeof(struct list_head));
1092 if (!ip_vs_conn_tab)
1095 /* Allocate ip_vs_conn slab cache */
1096 ip_vs_conn_cachep = kmem_cache_create("ip_vs_conn",
1097 sizeof(struct ip_vs_conn), 0,
1098 SLAB_HWCACHE_ALIGN, NULL);
1099 if (!ip_vs_conn_cachep) {
1100 vfree(ip_vs_conn_tab);
1104 pr_info("Connection hash table configured "
1105 "(size=%d, memory=%ldKbytes)\n",
1106 ip_vs_conn_tab_size,
1107 (long)(ip_vs_conn_tab_size*sizeof(struct list_head))/1024);
1108 IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n",
1109 sizeof(struct ip_vs_conn));
1111 for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
1112 INIT_LIST_HEAD(&ip_vs_conn_tab[idx]);
1115 for (idx = 0; idx < CT_LOCKARRAY_SIZE; idx++) {
1116 rwlock_init(&__ip_vs_conntbl_lock_array[idx].l);
1119 proc_net_fops_create(&init_net, "ip_vs_conn", 0, &ip_vs_conn_fops);
1120 proc_net_fops_create(&init_net, "ip_vs_conn_sync", 0, &ip_vs_conn_sync_fops);
1122 /* calculate the random value for connection hash */
1123 get_random_bytes(&ip_vs_conn_rnd, sizeof(ip_vs_conn_rnd));
1129 void ip_vs_conn_cleanup(void)
1131 /* flush all the connection entries first */
1134 /* Release the empty cache */
1135 kmem_cache_destroy(ip_vs_conn_cachep);
1136 proc_net_remove(&init_net, "ip_vs_conn");
1137 proc_net_remove(&init_net, "ip_vs_conn_sync");
1138 vfree(ip_vs_conn_tab);