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 static 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 __read_mostly;
57 static int ip_vs_conn_tab_mask __read_mostly;
60 * Connection hash table: for input and output packets lookups of IPVS
62 static struct hlist_head *ip_vs_conn_tab __read_mostly;
64 /* SLAB cache for IPVS connections */
65 static struct kmem_cache *ip_vs_conn_cachep __read_mostly;
67 /* counter for no client port connections */
68 static atomic_t ip_vs_conn_no_cport_cnt = ATOMIC_INIT(0);
70 /* random value for IPVS connection hash */
71 static unsigned int ip_vs_conn_rnd __read_mostly;
74 * Fine locking granularity for big connection hash table
76 #define CT_LOCKARRAY_BITS 5
77 #define CT_LOCKARRAY_SIZE (1<<CT_LOCKARRAY_BITS)
78 #define CT_LOCKARRAY_MASK (CT_LOCKARRAY_SIZE-1)
80 struct ip_vs_aligned_lock
83 } __attribute__((__aligned__(SMP_CACHE_BYTES)));
85 /* lock array for conn table */
86 static struct ip_vs_aligned_lock
87 __ip_vs_conntbl_lock_array[CT_LOCKARRAY_SIZE] __cacheline_aligned;
89 static inline void ct_write_lock_bh(unsigned int key)
91 spin_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
94 static inline void ct_write_unlock_bh(unsigned int key)
96 spin_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
101 * Returns hash value for IPVS connection entry
103 static unsigned int ip_vs_conn_hashkey(struct net *net, int af, unsigned int proto,
104 const union nf_inet_addr *addr,
107 #ifdef CONFIG_IP_VS_IPV6
109 return (jhash_3words(jhash(addr, 16, ip_vs_conn_rnd),
110 (__force u32)port, proto, ip_vs_conn_rnd) ^
111 ((size_t)net>>8)) & ip_vs_conn_tab_mask;
113 return (jhash_3words((__force u32)addr->ip, (__force u32)port, proto,
115 ((size_t)net>>8)) & ip_vs_conn_tab_mask;
118 static unsigned int ip_vs_conn_hashkey_param(const struct ip_vs_conn_param *p,
121 const union nf_inet_addr *addr;
124 if (p->pe_data && p->pe->hashkey_raw)
125 return p->pe->hashkey_raw(p, ip_vs_conn_rnd, inverse) &
128 if (likely(!inverse)) {
136 return ip_vs_conn_hashkey(p->net, p->af, p->protocol, addr, port);
139 static unsigned int ip_vs_conn_hashkey_conn(const struct ip_vs_conn *cp)
141 struct ip_vs_conn_param p;
143 ip_vs_conn_fill_param(ip_vs_conn_net(cp), cp->af, cp->protocol,
144 &cp->caddr, cp->cport, NULL, 0, &p);
148 p.pe_data = cp->pe_data;
149 p.pe_data_len = cp->pe_data_len;
152 return ip_vs_conn_hashkey_param(&p, false);
156 * Hashes ip_vs_conn in ip_vs_conn_tab by netns,proto,addr,port.
157 * returns bool success.
159 static inline int ip_vs_conn_hash(struct ip_vs_conn *cp)
164 if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
167 /* Hash by protocol, client address and port */
168 hash = ip_vs_conn_hashkey_conn(cp);
170 ct_write_lock_bh(hash);
171 spin_lock(&cp->lock);
173 if (!(cp->flags & IP_VS_CONN_F_HASHED)) {
174 cp->flags |= IP_VS_CONN_F_HASHED;
175 atomic_inc(&cp->refcnt);
176 hlist_add_head_rcu(&cp->c_list, &ip_vs_conn_tab[hash]);
179 pr_err("%s(): request for already hashed, called from %pF\n",
180 __func__, __builtin_return_address(0));
184 spin_unlock(&cp->lock);
185 ct_write_unlock_bh(hash);
192 * UNhashes ip_vs_conn from ip_vs_conn_tab.
193 * returns bool success. Caller should hold conn reference.
195 static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp)
200 /* unhash it and decrease its reference counter */
201 hash = ip_vs_conn_hashkey_conn(cp);
203 ct_write_lock_bh(hash);
204 spin_lock(&cp->lock);
206 if (cp->flags & IP_VS_CONN_F_HASHED) {
207 hlist_del_rcu(&cp->c_list);
208 cp->flags &= ~IP_VS_CONN_F_HASHED;
209 atomic_dec(&cp->refcnt);
214 spin_unlock(&cp->lock);
215 ct_write_unlock_bh(hash);
220 /* Try to unlink ip_vs_conn from ip_vs_conn_tab.
221 * returns bool success.
223 static inline bool ip_vs_conn_unlink(struct ip_vs_conn *cp)
228 hash = ip_vs_conn_hashkey_conn(cp);
230 ct_write_lock_bh(hash);
231 spin_lock(&cp->lock);
233 if (cp->flags & IP_VS_CONN_F_HASHED) {
235 /* Decrease refcnt and unlink conn only if we are last user */
236 if (atomic_cmpxchg(&cp->refcnt, 1, 0) == 1) {
237 hlist_del_rcu(&cp->c_list);
238 cp->flags &= ~IP_VS_CONN_F_HASHED;
242 ret = atomic_read(&cp->refcnt) ? false : true;
244 spin_unlock(&cp->lock);
245 ct_write_unlock_bh(hash);
252 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
253 * Called for pkts coming from OUTside-to-INside.
254 * p->caddr, p->cport: pkt source address (foreign host)
255 * p->vaddr, p->vport: pkt dest address (load balancer)
257 static inline struct ip_vs_conn *
258 __ip_vs_conn_in_get(const struct ip_vs_conn_param *p)
261 struct ip_vs_conn *cp;
263 hash = ip_vs_conn_hashkey_param(p, false);
267 hlist_for_each_entry_rcu(cp, &ip_vs_conn_tab[hash], c_list) {
268 if (p->cport == cp->cport && p->vport == cp->vport &&
270 ip_vs_addr_equal(p->af, p->caddr, &cp->caddr) &&
271 ip_vs_addr_equal(p->af, p->vaddr, &cp->vaddr) &&
272 ((!p->cport) ^ (!(cp->flags & IP_VS_CONN_F_NO_CPORT))) &&
273 p->protocol == cp->protocol &&
274 ip_vs_conn_net_eq(cp, p->net)) {
275 if (!__ip_vs_conn_get(cp))
288 struct ip_vs_conn *ip_vs_conn_in_get(const struct ip_vs_conn_param *p)
290 struct ip_vs_conn *cp;
292 cp = __ip_vs_conn_in_get(p);
293 if (!cp && atomic_read(&ip_vs_conn_no_cport_cnt)) {
294 struct ip_vs_conn_param cport_zero_p = *p;
295 cport_zero_p.cport = 0;
296 cp = __ip_vs_conn_in_get(&cport_zero_p);
299 IP_VS_DBG_BUF(9, "lookup/in %s %s:%d->%s:%d %s\n",
300 ip_vs_proto_name(p->protocol),
301 IP_VS_DBG_ADDR(p->af, p->caddr), ntohs(p->cport),
302 IP_VS_DBG_ADDR(p->af, p->vaddr), ntohs(p->vport),
303 cp ? "hit" : "not hit");
309 ip_vs_conn_fill_param_proto(int af, const struct sk_buff *skb,
310 const struct ip_vs_iphdr *iph,
311 int inverse, struct ip_vs_conn_param *p)
313 __be16 _ports[2], *pptr;
314 struct net *net = skb_net(skb);
316 pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports, iph);
320 if (likely(!inverse))
321 ip_vs_conn_fill_param(net, af, iph->protocol, &iph->saddr,
322 pptr[0], &iph->daddr, pptr[1], p);
324 ip_vs_conn_fill_param(net, af, iph->protocol, &iph->daddr,
325 pptr[1], &iph->saddr, pptr[0], p);
330 ip_vs_conn_in_get_proto(int af, const struct sk_buff *skb,
331 const struct ip_vs_iphdr *iph, int inverse)
333 struct ip_vs_conn_param p;
335 if (ip_vs_conn_fill_param_proto(af, skb, iph, inverse, &p))
338 return ip_vs_conn_in_get(&p);
340 EXPORT_SYMBOL_GPL(ip_vs_conn_in_get_proto);
342 /* Get reference to connection template */
343 struct ip_vs_conn *ip_vs_ct_in_get(const struct ip_vs_conn_param *p)
346 struct ip_vs_conn *cp;
348 hash = ip_vs_conn_hashkey_param(p, false);
352 hlist_for_each_entry_rcu(cp, &ip_vs_conn_tab[hash], c_list) {
353 if (unlikely(p->pe_data && p->pe->ct_match)) {
354 if (!ip_vs_conn_net_eq(cp, p->net))
356 if (p->pe == cp->pe && p->pe->ct_match(p, cp)) {
357 if (__ip_vs_conn_get(cp))
363 if (cp->af == p->af &&
364 ip_vs_addr_equal(p->af, p->caddr, &cp->caddr) &&
365 /* protocol should only be IPPROTO_IP if
366 * p->vaddr is a fwmark */
367 ip_vs_addr_equal(p->protocol == IPPROTO_IP ? AF_UNSPEC :
368 p->af, p->vaddr, &cp->vaddr) &&
369 p->vport == cp->vport && p->cport == cp->cport &&
370 cp->flags & IP_VS_CONN_F_TEMPLATE &&
371 p->protocol == cp->protocol &&
372 ip_vs_conn_net_eq(cp, p->net)) {
373 if (__ip_vs_conn_get(cp))
382 IP_VS_DBG_BUF(9, "template lookup/in %s %s:%d->%s:%d %s\n",
383 ip_vs_proto_name(p->protocol),
384 IP_VS_DBG_ADDR(p->af, p->caddr), ntohs(p->cport),
385 IP_VS_DBG_ADDR(p->af, p->vaddr), ntohs(p->vport),
386 cp ? "hit" : "not hit");
391 /* Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
392 * Called for pkts coming from inside-to-OUTside.
393 * p->caddr, p->cport: pkt source address (inside host)
394 * p->vaddr, p->vport: pkt dest address (foreign host) */
395 struct ip_vs_conn *ip_vs_conn_out_get(const struct ip_vs_conn_param *p)
398 struct ip_vs_conn *cp, *ret=NULL;
401 * Check for "full" addressed entries
403 hash = ip_vs_conn_hashkey_param(p, true);
407 hlist_for_each_entry_rcu(cp, &ip_vs_conn_tab[hash], c_list) {
408 if (p->vport == cp->cport && p->cport == cp->dport &&
410 ip_vs_addr_equal(p->af, p->vaddr, &cp->caddr) &&
411 ip_vs_addr_equal(p->af, p->caddr, &cp->daddr) &&
412 p->protocol == cp->protocol &&
413 ip_vs_conn_net_eq(cp, p->net)) {
414 if (!__ip_vs_conn_get(cp))
424 IP_VS_DBG_BUF(9, "lookup/out %s %s:%d->%s:%d %s\n",
425 ip_vs_proto_name(p->protocol),
426 IP_VS_DBG_ADDR(p->af, p->caddr), ntohs(p->cport),
427 IP_VS_DBG_ADDR(p->af, p->vaddr), ntohs(p->vport),
428 ret ? "hit" : "not hit");
434 ip_vs_conn_out_get_proto(int af, const struct sk_buff *skb,
435 const struct ip_vs_iphdr *iph, int inverse)
437 struct ip_vs_conn_param p;
439 if (ip_vs_conn_fill_param_proto(af, skb, iph, inverse, &p))
442 return ip_vs_conn_out_get(&p);
444 EXPORT_SYMBOL_GPL(ip_vs_conn_out_get_proto);
447 * Put back the conn and restart its timer with its timeout
449 void ip_vs_conn_put(struct ip_vs_conn *cp)
451 unsigned long t = (cp->flags & IP_VS_CONN_F_ONE_PACKET) ?
453 mod_timer(&cp->timer, jiffies+t);
455 __ip_vs_conn_put(cp);
460 * Fill a no_client_port connection with a client port number
462 void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport)
464 if (ip_vs_conn_unhash(cp)) {
465 spin_lock_bh(&cp->lock);
466 if (cp->flags & IP_VS_CONN_F_NO_CPORT) {
467 atomic_dec(&ip_vs_conn_no_cport_cnt);
468 cp->flags &= ~IP_VS_CONN_F_NO_CPORT;
471 spin_unlock_bh(&cp->lock);
473 /* hash on new dport */
480 * Bind a connection entry with the corresponding packet_xmit.
481 * Called by ip_vs_conn_new.
483 static inline void ip_vs_bind_xmit(struct ip_vs_conn *cp)
485 switch (IP_VS_FWD_METHOD(cp)) {
486 case IP_VS_CONN_F_MASQ:
487 cp->packet_xmit = ip_vs_nat_xmit;
490 case IP_VS_CONN_F_TUNNEL:
491 cp->packet_xmit = ip_vs_tunnel_xmit;
494 case IP_VS_CONN_F_DROUTE:
495 cp->packet_xmit = ip_vs_dr_xmit;
498 case IP_VS_CONN_F_LOCALNODE:
499 cp->packet_xmit = ip_vs_null_xmit;
502 case IP_VS_CONN_F_BYPASS:
503 cp->packet_xmit = ip_vs_bypass_xmit;
508 #ifdef CONFIG_IP_VS_IPV6
509 static inline void ip_vs_bind_xmit_v6(struct ip_vs_conn *cp)
511 switch (IP_VS_FWD_METHOD(cp)) {
512 case IP_VS_CONN_F_MASQ:
513 cp->packet_xmit = ip_vs_nat_xmit_v6;
516 case IP_VS_CONN_F_TUNNEL:
517 cp->packet_xmit = ip_vs_tunnel_xmit_v6;
520 case IP_VS_CONN_F_DROUTE:
521 cp->packet_xmit = ip_vs_dr_xmit_v6;
524 case IP_VS_CONN_F_LOCALNODE:
525 cp->packet_xmit = ip_vs_null_xmit;
528 case IP_VS_CONN_F_BYPASS:
529 cp->packet_xmit = ip_vs_bypass_xmit_v6;
536 static inline int ip_vs_dest_totalconns(struct ip_vs_dest *dest)
538 return atomic_read(&dest->activeconns)
539 + atomic_read(&dest->inactconns);
543 * Bind a connection entry with a virtual service destination
544 * Called just after a new connection entry is created.
547 ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
549 unsigned int conn_flags;
552 /* if dest is NULL, then return directly */
556 /* Increase the refcnt counter of the dest */
557 ip_vs_dest_hold(dest);
559 conn_flags = atomic_read(&dest->conn_flags);
560 if (cp->protocol != IPPROTO_UDP)
561 conn_flags &= ~IP_VS_CONN_F_ONE_PACKET;
563 /* Bind with the destination and its corresponding transmitter */
564 if (flags & IP_VS_CONN_F_SYNC) {
565 /* if the connection is not template and is created
566 * by sync, preserve the activity flag.
568 if (!(flags & IP_VS_CONN_F_TEMPLATE))
569 conn_flags &= ~IP_VS_CONN_F_INACTIVE;
570 /* connections inherit forwarding method from dest */
571 flags &= ~(IP_VS_CONN_F_FWD_MASK | IP_VS_CONN_F_NOOUTPUT);
577 IP_VS_DBG_BUF(7, "Bind-dest %s c:%s:%d v:%s:%d "
578 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
580 ip_vs_proto_name(cp->protocol),
581 IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
582 IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
583 IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
584 ip_vs_fwd_tag(cp), cp->state,
585 cp->flags, atomic_read(&cp->refcnt),
586 atomic_read(&dest->refcnt));
588 /* Update the connection counters */
589 if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
590 /* It is a normal connection, so modify the counters
591 * according to the flags, later the protocol can
592 * update them on state change
594 if (!(flags & IP_VS_CONN_F_INACTIVE))
595 atomic_inc(&dest->activeconns);
597 atomic_inc(&dest->inactconns);
599 /* It is a persistent connection/template, so increase
600 the persistent connection counter */
601 atomic_inc(&dest->persistconns);
604 if (dest->u_threshold != 0 &&
605 ip_vs_dest_totalconns(dest) >= dest->u_threshold)
606 dest->flags |= IP_VS_DEST_F_OVERLOAD;
611 * Check if there is a destination for the connection, if so
612 * bind the connection to the destination.
614 void ip_vs_try_bind_dest(struct ip_vs_conn *cp)
616 struct ip_vs_dest *dest;
619 dest = ip_vs_find_dest(ip_vs_conn_net(cp), cp->af, &cp->daddr,
620 cp->dport, &cp->vaddr, cp->vport,
621 cp->protocol, cp->fwmark, cp->flags);
623 struct ip_vs_proto_data *pd;
625 spin_lock_bh(&cp->lock);
627 spin_unlock_bh(&cp->lock);
632 /* Applications work depending on the forwarding method
633 * but better to reassign them always when binding dest */
635 ip_vs_unbind_app(cp);
637 ip_vs_bind_dest(cp, dest);
638 spin_unlock_bh(&cp->lock);
640 /* Update its packet transmitter */
641 cp->packet_xmit = NULL;
642 #ifdef CONFIG_IP_VS_IPV6
643 if (cp->af == AF_INET6)
644 ip_vs_bind_xmit_v6(cp);
649 pd = ip_vs_proto_data_get(ip_vs_conn_net(cp), cp->protocol);
650 if (pd && atomic_read(&pd->appcnt))
651 ip_vs_bind_app(cp, pd->pp);
658 * Unbind a connection entry with its VS destination
659 * Called by the ip_vs_conn_expire function.
661 static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp)
663 struct ip_vs_dest *dest = cp->dest;
668 IP_VS_DBG_BUF(7, "Unbind-dest %s c:%s:%d v:%s:%d "
669 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
671 ip_vs_proto_name(cp->protocol),
672 IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
673 IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
674 IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
675 ip_vs_fwd_tag(cp), cp->state,
676 cp->flags, atomic_read(&cp->refcnt),
677 atomic_read(&dest->refcnt));
679 /* Update the connection counters */
680 if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
681 /* It is a normal connection, so decrease the inactconns
682 or activeconns counter */
683 if (cp->flags & IP_VS_CONN_F_INACTIVE) {
684 atomic_dec(&dest->inactconns);
686 atomic_dec(&dest->activeconns);
689 /* It is a persistent connection/template, so decrease
690 the persistent connection counter */
691 atomic_dec(&dest->persistconns);
694 if (dest->l_threshold != 0) {
695 if (ip_vs_dest_totalconns(dest) < dest->l_threshold)
696 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
697 } else if (dest->u_threshold != 0) {
698 if (ip_vs_dest_totalconns(dest) * 4 < dest->u_threshold * 3)
699 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
701 if (dest->flags & IP_VS_DEST_F_OVERLOAD)
702 dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
705 ip_vs_dest_put(dest);
708 static int expire_quiescent_template(struct netns_ipvs *ipvs,
709 struct ip_vs_dest *dest)
712 return ipvs->sysctl_expire_quiescent_template &&
713 (atomic_read(&dest->weight) == 0);
720 * Checking if the destination of a connection template is available.
721 * If available, return 1, otherwise invalidate this connection
722 * template and return 0.
724 int ip_vs_check_template(struct ip_vs_conn *ct)
726 struct ip_vs_dest *dest = ct->dest;
727 struct netns_ipvs *ipvs = net_ipvs(ip_vs_conn_net(ct));
730 * Checking the dest server status.
732 if ((dest == NULL) ||
733 !(dest->flags & IP_VS_DEST_F_AVAILABLE) ||
734 expire_quiescent_template(ipvs, dest)) {
735 IP_VS_DBG_BUF(9, "check_template: dest not available for "
736 "protocol %s s:%s:%d v:%s:%d "
738 ip_vs_proto_name(ct->protocol),
739 IP_VS_DBG_ADDR(ct->af, &ct->caddr),
741 IP_VS_DBG_ADDR(ct->af, &ct->vaddr),
743 IP_VS_DBG_ADDR(ct->af, &ct->daddr),
747 * Invalidate the connection template
749 if (ct->vport != htons(0xffff)) {
750 if (ip_vs_conn_unhash(ct)) {
751 ct->dport = htons(0xffff);
752 ct->vport = htons(0xffff);
759 * Simply decrease the refcnt of the template,
760 * don't restart its timer.
762 __ip_vs_conn_put(ct);
768 static void ip_vs_conn_rcu_free(struct rcu_head *head)
770 struct ip_vs_conn *cp = container_of(head, struct ip_vs_conn,
773 ip_vs_pe_put(cp->pe);
775 kmem_cache_free(ip_vs_conn_cachep, cp);
778 static void ip_vs_conn_expire(unsigned long data)
780 struct ip_vs_conn *cp = (struct ip_vs_conn *)data;
781 struct net *net = ip_vs_conn_net(cp);
782 struct netns_ipvs *ipvs = net_ipvs(net);
785 * do I control anybody?
787 if (atomic_read(&cp->n_control))
790 /* Unlink conn if not referenced anymore */
791 if (likely(ip_vs_conn_unlink(cp))) {
792 /* delete the timer if it is activated by other users */
793 del_timer(&cp->timer);
795 /* does anybody control me? */
797 ip_vs_control_del(cp);
799 if (cp->flags & IP_VS_CONN_F_NFCT) {
800 ip_vs_conn_drop_conntrack(cp);
801 /* Do not access conntracks during subsys cleanup
802 * because nf_conntrack_find_get can not be used after
803 * conntrack cleanup for the net.
807 ip_vs_conn_drop_conntrack(cp);
810 if (unlikely(cp->app != NULL))
811 ip_vs_unbind_app(cp);
812 ip_vs_unbind_dest(cp);
813 if (cp->flags & IP_VS_CONN_F_NO_CPORT)
814 atomic_dec(&ip_vs_conn_no_cport_cnt);
815 call_rcu(&cp->rcu_head, ip_vs_conn_rcu_free);
816 atomic_dec(&ipvs->conn_count);
821 IP_VS_DBG(7, "delayed: conn->refcnt=%d conn->n_control=%d\n",
822 atomic_read(&cp->refcnt),
823 atomic_read(&cp->n_control));
825 atomic_inc(&cp->refcnt);
828 if (ipvs->sync_state & IP_VS_STATE_MASTER)
829 ip_vs_sync_conn(net, cp, sysctl_sync_threshold(ipvs));
834 /* Modify timer, so that it expires as soon as possible.
835 * Can be called without reference only if under RCU lock.
837 void ip_vs_conn_expire_now(struct ip_vs_conn *cp)
839 /* Using mod_timer_pending will ensure the timer is not
840 * modified after the final del_timer in ip_vs_conn_expire.
842 if (timer_pending(&cp->timer) &&
843 time_after(cp->timer.expires, jiffies))
844 mod_timer_pending(&cp->timer, jiffies);
849 * Create a new connection entry and hash it into the ip_vs_conn_tab
852 ip_vs_conn_new(const struct ip_vs_conn_param *p,
853 const union nf_inet_addr *daddr, __be16 dport, unsigned int flags,
854 struct ip_vs_dest *dest, __u32 fwmark)
856 struct ip_vs_conn *cp;
857 struct netns_ipvs *ipvs = net_ipvs(p->net);
858 struct ip_vs_proto_data *pd = ip_vs_proto_data_get(p->net,
861 cp = kmem_cache_alloc(ip_vs_conn_cachep, GFP_ATOMIC);
863 IP_VS_ERR_RL("%s(): no memory\n", __func__);
867 INIT_HLIST_NODE(&cp->c_list);
868 setup_timer(&cp->timer, ip_vs_conn_expire, (unsigned long)cp);
869 ip_vs_conn_net_set(cp, p->net);
871 cp->protocol = p->protocol;
872 ip_vs_addr_set(p->af, &cp->caddr, p->caddr);
873 cp->cport = p->cport;
874 /* proto should only be IPPROTO_IP if p->vaddr is a fwmark */
875 ip_vs_addr_set(p->protocol == IPPROTO_IP ? AF_UNSPEC : p->af,
876 &cp->vaddr, p->vaddr);
877 cp->vport = p->vport;
878 ip_vs_addr_set(p->af, &cp->daddr, daddr);
882 if (flags & IP_VS_CONN_F_TEMPLATE && p->pe) {
885 cp->pe_data = p->pe_data;
886 cp->pe_data_len = p->pe_data_len;
892 spin_lock_init(&cp->lock);
895 * Set the entry is referenced by the current thread before hashing
896 * it in the table, so that other thread run ip_vs_random_dropentry
897 * but cannot drop this entry.
899 atomic_set(&cp->refcnt, 1);
902 atomic_set(&cp->n_control, 0);
903 atomic_set(&cp->in_pkts, 0);
905 cp->packet_xmit = NULL;
908 /* reset struct ip_vs_seq */
909 cp->in_seq.delta = 0;
910 cp->out_seq.delta = 0;
912 atomic_inc(&ipvs->conn_count);
913 if (flags & IP_VS_CONN_F_NO_CPORT)
914 atomic_inc(&ip_vs_conn_no_cport_cnt);
916 /* Bind the connection with a destination server */
918 ip_vs_bind_dest(cp, dest);
920 /* Set its state and timeout */
924 cp->sync_endtime = jiffies & ~3UL;
926 /* Bind its packet transmitter */
927 #ifdef CONFIG_IP_VS_IPV6
928 if (p->af == AF_INET6)
929 ip_vs_bind_xmit_v6(cp);
934 if (unlikely(pd && atomic_read(&pd->appcnt)))
935 ip_vs_bind_app(cp, pd->pp);
938 * Allow conntrack to be preserved. By default, conntrack
939 * is created and destroyed for every packet.
940 * Sometimes keeping conntrack can be useful for
941 * IP_VS_CONN_F_ONE_PACKET too.
944 if (ip_vs_conntrack_enabled(ipvs))
945 cp->flags |= IP_VS_CONN_F_NFCT;
947 /* Hash it in the ip_vs_conn_tab finally */
954 * /proc/net/ip_vs_conn entries
956 #ifdef CONFIG_PROC_FS
957 struct ip_vs_iter_state {
958 struct seq_net_private p;
959 struct hlist_head *l;
962 static void *ip_vs_conn_array(struct seq_file *seq, loff_t pos)
965 struct ip_vs_conn *cp;
966 struct ip_vs_iter_state *iter = seq->private;
968 for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
969 hlist_for_each_entry_rcu(cp, &ip_vs_conn_tab[idx], c_list) {
970 /* __ip_vs_conn_get() is not needed by
971 * ip_vs_conn_seq_show and ip_vs_conn_sync_seq_show
974 iter->l = &ip_vs_conn_tab[idx];
984 static void *ip_vs_conn_seq_start(struct seq_file *seq, loff_t *pos)
987 struct ip_vs_iter_state *iter = seq->private;
991 return *pos ? ip_vs_conn_array(seq, *pos - 1) :SEQ_START_TOKEN;
994 static void *ip_vs_conn_seq_next(struct seq_file *seq, void *v, loff_t *pos)
996 struct ip_vs_conn *cp = v;
997 struct ip_vs_iter_state *iter = seq->private;
998 struct hlist_node *e;
999 struct hlist_head *l = iter->l;
1003 if (v == SEQ_START_TOKEN)
1004 return ip_vs_conn_array(seq, 0);
1006 /* more on same hash chain? */
1007 e = rcu_dereference(hlist_next_rcu(&cp->c_list));
1009 return hlist_entry(e, struct ip_vs_conn, c_list);
1011 idx = l - ip_vs_conn_tab;
1012 while (++idx < ip_vs_conn_tab_size) {
1013 hlist_for_each_entry_rcu(cp, &ip_vs_conn_tab[idx], c_list) {
1014 iter->l = &ip_vs_conn_tab[idx];
1023 static void ip_vs_conn_seq_stop(struct seq_file *seq, void *v)
1029 static int ip_vs_conn_seq_show(struct seq_file *seq, void *v)
1032 if (v == SEQ_START_TOKEN)
1034 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Expires PEName PEData\n");
1036 const struct ip_vs_conn *cp = v;
1037 struct net *net = seq_file_net(seq);
1038 char pe_data[IP_VS_PENAME_MAXLEN + IP_VS_PEDATA_MAXLEN + 3];
1041 if (!ip_vs_conn_net_eq(cp, net))
1045 len = strlen(cp->pe->name);
1046 memcpy(pe_data + 1, cp->pe->name, len);
1047 pe_data[len + 1] = ' ';
1049 len += cp->pe->show_pe_data(cp, pe_data + len);
1051 pe_data[len] = '\0';
1053 #ifdef CONFIG_IP_VS_IPV6
1054 if (cp->af == AF_INET6)
1055 seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X "
1056 "%pI6 %04X %-11s %7lu%s\n",
1057 ip_vs_proto_name(cp->protocol),
1058 &cp->caddr.in6, ntohs(cp->cport),
1059 &cp->vaddr.in6, ntohs(cp->vport),
1060 &cp->daddr.in6, ntohs(cp->dport),
1061 ip_vs_state_name(cp->protocol, cp->state),
1062 (cp->timer.expires-jiffies)/HZ, pe_data);
1066 "%-3s %08X %04X %08X %04X"
1067 " %08X %04X %-11s %7lu%s\n",
1068 ip_vs_proto_name(cp->protocol),
1069 ntohl(cp->caddr.ip), ntohs(cp->cport),
1070 ntohl(cp->vaddr.ip), ntohs(cp->vport),
1071 ntohl(cp->daddr.ip), ntohs(cp->dport),
1072 ip_vs_state_name(cp->protocol, cp->state),
1073 (cp->timer.expires-jiffies)/HZ, pe_data);
1078 static const struct seq_operations ip_vs_conn_seq_ops = {
1079 .start = ip_vs_conn_seq_start,
1080 .next = ip_vs_conn_seq_next,
1081 .stop = ip_vs_conn_seq_stop,
1082 .show = ip_vs_conn_seq_show,
1085 static int ip_vs_conn_open(struct inode *inode, struct file *file)
1087 return seq_open_net(inode, file, &ip_vs_conn_seq_ops,
1088 sizeof(struct ip_vs_iter_state));
1091 static const struct file_operations ip_vs_conn_fops = {
1092 .owner = THIS_MODULE,
1093 .open = ip_vs_conn_open,
1095 .llseek = seq_lseek,
1096 .release = seq_release_net,
1099 static const char *ip_vs_origin_name(unsigned int flags)
1101 if (flags & IP_VS_CONN_F_SYNC)
1107 static int ip_vs_conn_sync_seq_show(struct seq_file *seq, void *v)
1110 if (v == SEQ_START_TOKEN)
1112 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Origin Expires\n");
1114 const struct ip_vs_conn *cp = v;
1115 struct net *net = seq_file_net(seq);
1117 if (!ip_vs_conn_net_eq(cp, net))
1120 #ifdef CONFIG_IP_VS_IPV6
1121 if (cp->af == AF_INET6)
1122 seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %-6s %7lu\n",
1123 ip_vs_proto_name(cp->protocol),
1124 &cp->caddr.in6, ntohs(cp->cport),
1125 &cp->vaddr.in6, ntohs(cp->vport),
1126 &cp->daddr.in6, ntohs(cp->dport),
1127 ip_vs_state_name(cp->protocol, cp->state),
1128 ip_vs_origin_name(cp->flags),
1129 (cp->timer.expires-jiffies)/HZ);
1133 "%-3s %08X %04X %08X %04X "
1134 "%08X %04X %-11s %-6s %7lu\n",
1135 ip_vs_proto_name(cp->protocol),
1136 ntohl(cp->caddr.ip), ntohs(cp->cport),
1137 ntohl(cp->vaddr.ip), ntohs(cp->vport),
1138 ntohl(cp->daddr.ip), ntohs(cp->dport),
1139 ip_vs_state_name(cp->protocol, cp->state),
1140 ip_vs_origin_name(cp->flags),
1141 (cp->timer.expires-jiffies)/HZ);
1146 static const struct seq_operations ip_vs_conn_sync_seq_ops = {
1147 .start = ip_vs_conn_seq_start,
1148 .next = ip_vs_conn_seq_next,
1149 .stop = ip_vs_conn_seq_stop,
1150 .show = ip_vs_conn_sync_seq_show,
1153 static int ip_vs_conn_sync_open(struct inode *inode, struct file *file)
1155 return seq_open_net(inode, file, &ip_vs_conn_sync_seq_ops,
1156 sizeof(struct ip_vs_iter_state));
1159 static const struct file_operations ip_vs_conn_sync_fops = {
1160 .owner = THIS_MODULE,
1161 .open = ip_vs_conn_sync_open,
1163 .llseek = seq_lseek,
1164 .release = seq_release_net,
1171 * Randomly drop connection entries before running out of memory
1173 static inline int todrop_entry(struct ip_vs_conn *cp)
1176 * The drop rate array needs tuning for real environments.
1177 * Called from timer bh only => no locking
1179 static const char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
1180 static char todrop_counter[9] = {0};
1183 /* if the conn entry hasn't lasted for 60 seconds, don't drop it.
1184 This will leave enough time for normal connection to get
1186 if (time_before(cp->timeout + jiffies, cp->timer.expires + 60*HZ))
1189 /* Don't drop the entry if its number of incoming packets is not
1190 located in [0, 8] */
1191 i = atomic_read(&cp->in_pkts);
1192 if (i > 8 || i < 0) return 0;
1194 if (!todrop_rate[i]) return 0;
1195 if (--todrop_counter[i] > 0) return 0;
1197 todrop_counter[i] = todrop_rate[i];
1201 /* Called from keventd and must protect itself from softirqs */
1202 void ip_vs_random_dropentry(struct net *net)
1205 struct ip_vs_conn *cp, *cp_c;
1209 * Randomly scan 1/32 of the whole table every second
1211 for (idx = 0; idx < (ip_vs_conn_tab_size>>5); idx++) {
1212 unsigned int hash = prandom_u32() & ip_vs_conn_tab_mask;
1214 hlist_for_each_entry_rcu(cp, &ip_vs_conn_tab[hash], c_list) {
1215 if (cp->flags & IP_VS_CONN_F_TEMPLATE)
1216 /* connection template */
1218 if (!ip_vs_conn_net_eq(cp, net))
1220 if (cp->protocol == IPPROTO_TCP) {
1222 case IP_VS_TCP_S_SYN_RECV:
1223 case IP_VS_TCP_S_SYNACK:
1226 case IP_VS_TCP_S_ESTABLISHED:
1227 if (todrop_entry(cp))
1234 } else if (cp->protocol == IPPROTO_SCTP) {
1235 switch (cp->state) {
1236 case IP_VS_SCTP_S_INIT1:
1237 case IP_VS_SCTP_S_INIT:
1239 case IP_VS_SCTP_S_ESTABLISHED:
1240 if (todrop_entry(cp))
1247 if (!todrop_entry(cp))
1251 IP_VS_DBG(4, "del connection\n");
1252 ip_vs_conn_expire_now(cp);
1254 /* cp->control is valid only with reference to cp */
1255 if (cp_c && __ip_vs_conn_get(cp)) {
1256 IP_VS_DBG(4, "del conn template\n");
1257 ip_vs_conn_expire_now(cp_c);
1258 __ip_vs_conn_put(cp);
1268 * Flush all the connection entries in the ip_vs_conn_tab
1270 static void ip_vs_conn_flush(struct net *net)
1273 struct ip_vs_conn *cp, *cp_c;
1274 struct netns_ipvs *ipvs = net_ipvs(net);
1278 for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
1280 hlist_for_each_entry_rcu(cp, &ip_vs_conn_tab[idx], c_list) {
1281 if (!ip_vs_conn_net_eq(cp, net))
1283 IP_VS_DBG(4, "del connection\n");
1284 ip_vs_conn_expire_now(cp);
1286 /* cp->control is valid only with reference to cp */
1287 if (cp_c && __ip_vs_conn_get(cp)) {
1288 IP_VS_DBG(4, "del conn template\n");
1289 ip_vs_conn_expire_now(cp_c);
1290 __ip_vs_conn_put(cp);
1297 /* the counter may be not NULL, because maybe some conn entries
1298 are run by slow timer handler or unhashed but still referred */
1299 if (atomic_read(&ipvs->conn_count) != 0) {
1305 * per netns init and exit
1307 int __net_init ip_vs_conn_net_init(struct net *net)
1309 struct netns_ipvs *ipvs = net_ipvs(net);
1311 atomic_set(&ipvs->conn_count, 0);
1313 proc_create("ip_vs_conn", 0, net->proc_net, &ip_vs_conn_fops);
1314 proc_create("ip_vs_conn_sync", 0, net->proc_net, &ip_vs_conn_sync_fops);
1318 void __net_exit ip_vs_conn_net_cleanup(struct net *net)
1320 /* flush all the connection entries first */
1321 ip_vs_conn_flush(net);
1322 remove_proc_entry("ip_vs_conn", net->proc_net);
1323 remove_proc_entry("ip_vs_conn_sync", net->proc_net);
1326 int __init ip_vs_conn_init(void)
1330 /* Compute size and mask */
1331 ip_vs_conn_tab_size = 1 << ip_vs_conn_tab_bits;
1332 ip_vs_conn_tab_mask = ip_vs_conn_tab_size - 1;
1335 * Allocate the connection hash table and initialize its list heads
1337 ip_vs_conn_tab = vmalloc(ip_vs_conn_tab_size * sizeof(*ip_vs_conn_tab));
1338 if (!ip_vs_conn_tab)
1341 /* Allocate ip_vs_conn slab cache */
1342 ip_vs_conn_cachep = kmem_cache_create("ip_vs_conn",
1343 sizeof(struct ip_vs_conn), 0,
1344 SLAB_HWCACHE_ALIGN, NULL);
1345 if (!ip_vs_conn_cachep) {
1346 vfree(ip_vs_conn_tab);
1350 pr_info("Connection hash table configured "
1351 "(size=%d, memory=%ldKbytes)\n",
1352 ip_vs_conn_tab_size,
1353 (long)(ip_vs_conn_tab_size*sizeof(struct list_head))/1024);
1354 IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n",
1355 sizeof(struct ip_vs_conn));
1357 for (idx = 0; idx < ip_vs_conn_tab_size; idx++)
1358 INIT_HLIST_HEAD(&ip_vs_conn_tab[idx]);
1360 for (idx = 0; idx < CT_LOCKARRAY_SIZE; idx++) {
1361 spin_lock_init(&__ip_vs_conntbl_lock_array[idx].l);
1364 /* calculate the random value for connection hash */
1365 get_random_bytes(&ip_vs_conn_rnd, sizeof(ip_vs_conn_rnd));
1370 void ip_vs_conn_cleanup(void)
1372 /* Wait all ip_vs_conn_rcu_free() callbacks to complete */
1374 /* Release the empty cache */
1375 kmem_cache_destroy(ip_vs_conn_cachep);
1376 vfree(ip_vs_conn_tab);