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 if (cp
->flags
& IP_VS_CONN_F_ONE_PACKET
)
164 /* Hash by protocol, client address and port */
165 hash
= ip_vs_conn_hashkey(cp
->af
, cp
->protocol
, &cp
->caddr
, cp
->cport
);
168 spin_lock(&cp
->lock
);
170 if (!(cp
->flags
& IP_VS_CONN_F_HASHED
)) {
171 list_add(&cp
->c_list
, &ip_vs_conn_tab
[hash
]);
172 cp
->flags
|= IP_VS_CONN_F_HASHED
;
173 atomic_inc(&cp
->refcnt
);
176 pr_err("%s(): request for already hashed, called from %pF\n",
177 __func__
, __builtin_return_address(0));
181 spin_unlock(&cp
->lock
);
182 ct_write_unlock(hash
);
189 * UNhashes ip_vs_conn from ip_vs_conn_tab.
190 * returns bool success.
192 static inline int ip_vs_conn_unhash(struct ip_vs_conn
*cp
)
197 /* unhash it and decrease its reference counter */
198 hash
= ip_vs_conn_hashkey(cp
->af
, cp
->protocol
, &cp
->caddr
, cp
->cport
);
201 spin_lock(&cp
->lock
);
203 if (cp
->flags
& IP_VS_CONN_F_HASHED
) {
204 list_del(&cp
->c_list
);
205 cp
->flags
&= ~IP_VS_CONN_F_HASHED
;
206 atomic_dec(&cp
->refcnt
);
211 spin_unlock(&cp
->lock
);
212 ct_write_unlock(hash
);
219 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
220 * Called for pkts coming from OUTside-to-INside.
221 * s_addr, s_port: pkt source address (foreign host)
222 * d_addr, d_port: pkt dest address (load balancer)
224 static inline struct ip_vs_conn
*__ip_vs_conn_in_get
225 (int af
, int protocol
, const union nf_inet_addr
*s_addr
, __be16 s_port
,
226 const union nf_inet_addr
*d_addr
, __be16 d_port
)
229 struct ip_vs_conn
*cp
;
231 hash
= ip_vs_conn_hashkey(af
, protocol
, s_addr
, s_port
);
235 list_for_each_entry(cp
, &ip_vs_conn_tab
[hash
], c_list
) {
237 ip_vs_addr_equal(af
, s_addr
, &cp
->caddr
) &&
238 ip_vs_addr_equal(af
, d_addr
, &cp
->vaddr
) &&
239 s_port
== cp
->cport
&& d_port
== cp
->vport
&&
240 ((!s_port
) ^ (!(cp
->flags
& IP_VS_CONN_F_NO_CPORT
))) &&
241 protocol
== cp
->protocol
) {
243 atomic_inc(&cp
->refcnt
);
244 ct_read_unlock(hash
);
249 ct_read_unlock(hash
);
254 struct ip_vs_conn
*ip_vs_conn_in_get
255 (int af
, int protocol
, const union nf_inet_addr
*s_addr
, __be16 s_port
,
256 const union nf_inet_addr
*d_addr
, __be16 d_port
)
258 struct ip_vs_conn
*cp
;
260 cp
= __ip_vs_conn_in_get(af
, protocol
, s_addr
, s_port
, d_addr
, d_port
);
261 if (!cp
&& atomic_read(&ip_vs_conn_no_cport_cnt
))
262 cp
= __ip_vs_conn_in_get(af
, protocol
, s_addr
, 0, d_addr
,
265 IP_VS_DBG_BUF(9, "lookup/in %s %s:%d->%s:%d %s\n",
266 ip_vs_proto_name(protocol
),
267 IP_VS_DBG_ADDR(af
, s_addr
), ntohs(s_port
),
268 IP_VS_DBG_ADDR(af
, d_addr
), ntohs(d_port
),
269 cp
? "hit" : "not hit");
275 ip_vs_conn_in_get_proto(int af
, const struct sk_buff
*skb
,
276 struct ip_vs_protocol
*pp
,
277 const struct ip_vs_iphdr
*iph
,
278 unsigned int proto_off
, int inverse
)
280 __be16 _ports
[2], *pptr
;
282 pptr
= skb_header_pointer(skb
, proto_off
, sizeof(_ports
), _ports
);
286 if (likely(!inverse
))
287 return ip_vs_conn_in_get(af
, iph
->protocol
,
288 &iph
->saddr
, pptr
[0],
289 &iph
->daddr
, pptr
[1]);
291 return ip_vs_conn_in_get(af
, iph
->protocol
,
292 &iph
->daddr
, pptr
[1],
293 &iph
->saddr
, pptr
[0]);
295 EXPORT_SYMBOL_GPL(ip_vs_conn_in_get_proto
);
297 /* Get reference to connection template */
298 struct ip_vs_conn
*ip_vs_ct_in_get
299 (int af
, int protocol
, const union nf_inet_addr
*s_addr
, __be16 s_port
,
300 const union nf_inet_addr
*d_addr
, __be16 d_port
)
303 struct ip_vs_conn
*cp
;
305 hash
= ip_vs_conn_hashkey(af
, protocol
, s_addr
, s_port
);
309 list_for_each_entry(cp
, &ip_vs_conn_tab
[hash
], c_list
) {
311 ip_vs_addr_equal(af
, s_addr
, &cp
->caddr
) &&
312 /* protocol should only be IPPROTO_IP if
313 * d_addr is a fwmark */
314 ip_vs_addr_equal(protocol
== IPPROTO_IP
? AF_UNSPEC
: af
,
315 d_addr
, &cp
->vaddr
) &&
316 s_port
== cp
->cport
&& d_port
== cp
->vport
&&
317 cp
->flags
& IP_VS_CONN_F_TEMPLATE
&&
318 protocol
== cp
->protocol
) {
320 atomic_inc(&cp
->refcnt
);
327 ct_read_unlock(hash
);
329 IP_VS_DBG_BUF(9, "template lookup/in %s %s:%d->%s:%d %s\n",
330 ip_vs_proto_name(protocol
),
331 IP_VS_DBG_ADDR(af
, s_addr
), ntohs(s_port
),
332 IP_VS_DBG_ADDR(af
, d_addr
), ntohs(d_port
),
333 cp
? "hit" : "not hit");
339 * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
340 * Called for pkts coming from inside-to-OUTside.
341 * s_addr, s_port: pkt source address (inside host)
342 * d_addr, d_port: pkt dest address (foreign host)
344 struct ip_vs_conn
*ip_vs_conn_out_get
345 (int af
, int protocol
, const union nf_inet_addr
*s_addr
, __be16 s_port
,
346 const union nf_inet_addr
*d_addr
, __be16 d_port
)
349 struct ip_vs_conn
*cp
, *ret
=NULL
;
352 * Check for "full" addressed entries
354 hash
= ip_vs_conn_hashkey(af
, protocol
, d_addr
, d_port
);
358 list_for_each_entry(cp
, &ip_vs_conn_tab
[hash
], c_list
) {
360 ip_vs_addr_equal(af
, d_addr
, &cp
->caddr
) &&
361 ip_vs_addr_equal(af
, s_addr
, &cp
->daddr
) &&
362 d_port
== cp
->cport
&& s_port
== cp
->dport
&&
363 protocol
== cp
->protocol
) {
365 atomic_inc(&cp
->refcnt
);
371 ct_read_unlock(hash
);
373 IP_VS_DBG_BUF(9, "lookup/out %s %s:%d->%s:%d %s\n",
374 ip_vs_proto_name(protocol
),
375 IP_VS_DBG_ADDR(af
, s_addr
), ntohs(s_port
),
376 IP_VS_DBG_ADDR(af
, d_addr
), ntohs(d_port
),
377 ret
? "hit" : "not hit");
383 ip_vs_conn_out_get_proto(int af
, const struct sk_buff
*skb
,
384 struct ip_vs_protocol
*pp
,
385 const struct ip_vs_iphdr
*iph
,
386 unsigned int proto_off
, int inverse
)
388 __be16 _ports
[2], *pptr
;
390 pptr
= skb_header_pointer(skb
, proto_off
, sizeof(_ports
), _ports
);
394 if (likely(!inverse
))
395 return ip_vs_conn_out_get(af
, iph
->protocol
,
396 &iph
->saddr
, pptr
[0],
397 &iph
->daddr
, pptr
[1]);
399 return ip_vs_conn_out_get(af
, iph
->protocol
,
400 &iph
->daddr
, pptr
[1],
401 &iph
->saddr
, pptr
[0]);
403 EXPORT_SYMBOL_GPL(ip_vs_conn_out_get_proto
);
406 * Put back the conn and restart its timer with its timeout
408 void ip_vs_conn_put(struct ip_vs_conn
*cp
)
410 unsigned long t
= (cp
->flags
& IP_VS_CONN_F_ONE_PACKET
) ?
412 mod_timer(&cp
->timer
, jiffies
+t
);
414 __ip_vs_conn_put(cp
);
419 * Fill a no_client_port connection with a client port number
421 void ip_vs_conn_fill_cport(struct ip_vs_conn
*cp
, __be16 cport
)
423 if (ip_vs_conn_unhash(cp
)) {
424 spin_lock(&cp
->lock
);
425 if (cp
->flags
& IP_VS_CONN_F_NO_CPORT
) {
426 atomic_dec(&ip_vs_conn_no_cport_cnt
);
427 cp
->flags
&= ~IP_VS_CONN_F_NO_CPORT
;
430 spin_unlock(&cp
->lock
);
432 /* hash on new dport */
439 * Bind a connection entry with the corresponding packet_xmit.
440 * Called by ip_vs_conn_new.
442 static inline void ip_vs_bind_xmit(struct ip_vs_conn
*cp
)
444 switch (IP_VS_FWD_METHOD(cp
)) {
445 case IP_VS_CONN_F_MASQ
:
446 cp
->packet_xmit
= ip_vs_nat_xmit
;
449 case IP_VS_CONN_F_TUNNEL
:
450 cp
->packet_xmit
= ip_vs_tunnel_xmit
;
453 case IP_VS_CONN_F_DROUTE
:
454 cp
->packet_xmit
= ip_vs_dr_xmit
;
457 case IP_VS_CONN_F_LOCALNODE
:
458 cp
->packet_xmit
= ip_vs_null_xmit
;
461 case IP_VS_CONN_F_BYPASS
:
462 cp
->packet_xmit
= ip_vs_bypass_xmit
;
467 #ifdef CONFIG_IP_VS_IPV6
468 static inline void ip_vs_bind_xmit_v6(struct ip_vs_conn
*cp
)
470 switch (IP_VS_FWD_METHOD(cp
)) {
471 case IP_VS_CONN_F_MASQ
:
472 cp
->packet_xmit
= ip_vs_nat_xmit_v6
;
475 case IP_VS_CONN_F_TUNNEL
:
476 cp
->packet_xmit
= ip_vs_tunnel_xmit_v6
;
479 case IP_VS_CONN_F_DROUTE
:
480 cp
->packet_xmit
= ip_vs_dr_xmit_v6
;
483 case IP_VS_CONN_F_LOCALNODE
:
484 cp
->packet_xmit
= ip_vs_null_xmit
;
487 case IP_VS_CONN_F_BYPASS
:
488 cp
->packet_xmit
= ip_vs_bypass_xmit_v6
;
495 static inline int ip_vs_dest_totalconns(struct ip_vs_dest
*dest
)
497 return atomic_read(&dest
->activeconns
)
498 + atomic_read(&dest
->inactconns
);
502 * Bind a connection entry with a virtual service destination
503 * Called just after a new connection entry is created.
506 ip_vs_bind_dest(struct ip_vs_conn
*cp
, struct ip_vs_dest
*dest
)
508 /* if dest is NULL, then return directly */
512 /* Increase the refcnt counter of the dest */
513 atomic_inc(&dest
->refcnt
);
515 /* Bind with the destination and its corresponding transmitter */
516 if ((cp
->flags
& IP_VS_CONN_F_SYNC
) &&
517 (!(cp
->flags
& IP_VS_CONN_F_TEMPLATE
)))
518 /* if the connection is not template and is created
519 * by sync, preserve the activity flag.
521 cp
->flags
|= atomic_read(&dest
->conn_flags
) &
522 (~IP_VS_CONN_F_INACTIVE
);
524 cp
->flags
|= atomic_read(&dest
->conn_flags
);
527 IP_VS_DBG_BUF(7, "Bind-dest %s c:%s:%d v:%s:%d "
528 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
530 ip_vs_proto_name(cp
->protocol
),
531 IP_VS_DBG_ADDR(cp
->af
, &cp
->caddr
), ntohs(cp
->cport
),
532 IP_VS_DBG_ADDR(cp
->af
, &cp
->vaddr
), ntohs(cp
->vport
),
533 IP_VS_DBG_ADDR(cp
->af
, &cp
->daddr
), ntohs(cp
->dport
),
534 ip_vs_fwd_tag(cp
), cp
->state
,
535 cp
->flags
, atomic_read(&cp
->refcnt
),
536 atomic_read(&dest
->refcnt
));
538 /* Update the connection counters */
539 if (!(cp
->flags
& IP_VS_CONN_F_TEMPLATE
)) {
540 /* It is a normal connection, so increase the inactive
541 connection counter because it is in TCP SYNRECV
542 state (inactive) or other protocol inacive state */
543 if ((cp
->flags
& IP_VS_CONN_F_SYNC
) &&
544 (!(cp
->flags
& IP_VS_CONN_F_INACTIVE
)))
545 atomic_inc(&dest
->activeconns
);
547 atomic_inc(&dest
->inactconns
);
549 /* It is a persistent connection/template, so increase
550 the peristent connection counter */
551 atomic_inc(&dest
->persistconns
);
554 if (dest
->u_threshold
!= 0 &&
555 ip_vs_dest_totalconns(dest
) >= dest
->u_threshold
)
556 dest
->flags
|= IP_VS_DEST_F_OVERLOAD
;
561 * Check if there is a destination for the connection, if so
562 * bind the connection to the destination.
564 struct ip_vs_dest
*ip_vs_try_bind_dest(struct ip_vs_conn
*cp
)
566 struct ip_vs_dest
*dest
;
568 if ((cp
) && (!cp
->dest
)) {
569 dest
= ip_vs_find_dest(cp
->af
, &cp
->daddr
, cp
->dport
,
570 &cp
->vaddr
, cp
->vport
,
572 ip_vs_bind_dest(cp
, dest
);
580 * Unbind a connection entry with its VS destination
581 * Called by the ip_vs_conn_expire function.
583 static inline void ip_vs_unbind_dest(struct ip_vs_conn
*cp
)
585 struct ip_vs_dest
*dest
= cp
->dest
;
590 IP_VS_DBG_BUF(7, "Unbind-dest %s c:%s:%d v:%s:%d "
591 "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
593 ip_vs_proto_name(cp
->protocol
),
594 IP_VS_DBG_ADDR(cp
->af
, &cp
->caddr
), ntohs(cp
->cport
),
595 IP_VS_DBG_ADDR(cp
->af
, &cp
->vaddr
), ntohs(cp
->vport
),
596 IP_VS_DBG_ADDR(cp
->af
, &cp
->daddr
), ntohs(cp
->dport
),
597 ip_vs_fwd_tag(cp
), cp
->state
,
598 cp
->flags
, atomic_read(&cp
->refcnt
),
599 atomic_read(&dest
->refcnt
));
601 /* Update the connection counters */
602 if (!(cp
->flags
& IP_VS_CONN_F_TEMPLATE
)) {
603 /* It is a normal connection, so decrease the inactconns
604 or activeconns counter */
605 if (cp
->flags
& IP_VS_CONN_F_INACTIVE
) {
606 atomic_dec(&dest
->inactconns
);
608 atomic_dec(&dest
->activeconns
);
611 /* It is a persistent connection/template, so decrease
612 the peristent connection counter */
613 atomic_dec(&dest
->persistconns
);
616 if (dest
->l_threshold
!= 0) {
617 if (ip_vs_dest_totalconns(dest
) < dest
->l_threshold
)
618 dest
->flags
&= ~IP_VS_DEST_F_OVERLOAD
;
619 } else if (dest
->u_threshold
!= 0) {
620 if (ip_vs_dest_totalconns(dest
) * 4 < dest
->u_threshold
* 3)
621 dest
->flags
&= ~IP_VS_DEST_F_OVERLOAD
;
623 if (dest
->flags
& IP_VS_DEST_F_OVERLOAD
)
624 dest
->flags
&= ~IP_VS_DEST_F_OVERLOAD
;
628 * Simply decrease the refcnt of the dest, because the
629 * dest will be either in service's destination list
632 atomic_dec(&dest
->refcnt
);
637 * Checking if the destination of a connection template is available.
638 * If available, return 1, otherwise invalidate this connection
639 * template and return 0.
641 int ip_vs_check_template(struct ip_vs_conn
*ct
)
643 struct ip_vs_dest
*dest
= ct
->dest
;
646 * Checking the dest server status.
648 if ((dest
== NULL
) ||
649 !(dest
->flags
& IP_VS_DEST_F_AVAILABLE
) ||
650 (sysctl_ip_vs_expire_quiescent_template
&&
651 (atomic_read(&dest
->weight
) == 0))) {
652 IP_VS_DBG_BUF(9, "check_template: dest not available for "
653 "protocol %s s:%s:%d v:%s:%d "
655 ip_vs_proto_name(ct
->protocol
),
656 IP_VS_DBG_ADDR(ct
->af
, &ct
->caddr
),
658 IP_VS_DBG_ADDR(ct
->af
, &ct
->vaddr
),
660 IP_VS_DBG_ADDR(ct
->af
, &ct
->daddr
),
664 * Invalidate the connection template
666 if (ct
->vport
!= htons(0xffff)) {
667 if (ip_vs_conn_unhash(ct
)) {
668 ct
->dport
= htons(0xffff);
669 ct
->vport
= htons(0xffff);
676 * Simply decrease the refcnt of the template,
677 * don't restart its timer.
679 atomic_dec(&ct
->refcnt
);
685 static void ip_vs_conn_expire(unsigned long data
)
687 struct ip_vs_conn
*cp
= (struct ip_vs_conn
*)data
;
694 atomic_inc(&cp
->refcnt
);
697 * do I control anybody?
699 if (atomic_read(&cp
->n_control
))
703 * unhash it if it is hashed in the conn table
705 if (!ip_vs_conn_unhash(cp
) && !(cp
->flags
& IP_VS_CONN_F_ONE_PACKET
))
709 * refcnt==1 implies I'm the only one referrer
711 if (likely(atomic_read(&cp
->refcnt
) == 1)) {
712 /* delete the timer if it is activated by other users */
713 if (timer_pending(&cp
->timer
))
714 del_timer(&cp
->timer
);
716 /* does anybody control me? */
718 ip_vs_control_del(cp
);
720 if (unlikely(cp
->app
!= NULL
))
721 ip_vs_unbind_app(cp
);
722 ip_vs_unbind_dest(cp
);
723 if (cp
->flags
& IP_VS_CONN_F_NO_CPORT
)
724 atomic_dec(&ip_vs_conn_no_cport_cnt
);
725 atomic_dec(&ip_vs_conn_count
);
727 kmem_cache_free(ip_vs_conn_cachep
, cp
);
731 /* hash it back to the table */
735 IP_VS_DBG(7, "delayed: conn->refcnt-1=%d conn->n_control=%d\n",
736 atomic_read(&cp
->refcnt
)-1,
737 atomic_read(&cp
->n_control
));
743 void ip_vs_conn_expire_now(struct ip_vs_conn
*cp
)
745 if (del_timer(&cp
->timer
))
746 mod_timer(&cp
->timer
, jiffies
);
751 * Create a new connection entry and hash it into the ip_vs_conn_tab
754 ip_vs_conn_new(int af
, int proto
, const union nf_inet_addr
*caddr
, __be16 cport
,
755 const union nf_inet_addr
*vaddr
, __be16 vport
,
756 const union nf_inet_addr
*daddr
, __be16 dport
, unsigned flags
,
757 struct ip_vs_dest
*dest
)
759 struct ip_vs_conn
*cp
;
760 struct ip_vs_protocol
*pp
= ip_vs_proto_get(proto
);
762 cp
= kmem_cache_zalloc(ip_vs_conn_cachep
, GFP_ATOMIC
);
764 IP_VS_ERR_RL("%s(): no memory\n", __func__
);
768 INIT_LIST_HEAD(&cp
->c_list
);
769 setup_timer(&cp
->timer
, ip_vs_conn_expire
, (unsigned long)cp
);
771 cp
->protocol
= proto
;
772 ip_vs_addr_copy(af
, &cp
->caddr
, caddr
);
774 ip_vs_addr_copy(af
, &cp
->vaddr
, vaddr
);
776 /* proto should only be IPPROTO_IP if d_addr is a fwmark */
777 ip_vs_addr_copy(proto
== IPPROTO_IP
? AF_UNSPEC
: af
,
781 spin_lock_init(&cp
->lock
);
784 * Set the entry is referenced by the current thread before hashing
785 * it in the table, so that other thread run ip_vs_random_dropentry
786 * but cannot drop this entry.
788 atomic_set(&cp
->refcnt
, 1);
790 atomic_set(&cp
->n_control
, 0);
791 atomic_set(&cp
->in_pkts
, 0);
793 atomic_inc(&ip_vs_conn_count
);
794 if (flags
& IP_VS_CONN_F_NO_CPORT
)
795 atomic_inc(&ip_vs_conn_no_cport_cnt
);
797 /* Bind the connection with a destination server */
798 ip_vs_bind_dest(cp
, dest
);
800 /* Set its state and timeout */
804 /* Bind its packet transmitter */
805 #ifdef CONFIG_IP_VS_IPV6
807 ip_vs_bind_xmit_v6(cp
);
812 if (unlikely(pp
&& atomic_read(&pp
->appcnt
)))
813 ip_vs_bind_app(cp
, pp
);
815 /* Hash it in the ip_vs_conn_tab finally */
823 * /proc/net/ip_vs_conn entries
825 #ifdef CONFIG_PROC_FS
827 static void *ip_vs_conn_array(struct seq_file
*seq
, loff_t pos
)
830 struct ip_vs_conn
*cp
;
832 for (idx
= 0; idx
< ip_vs_conn_tab_size
; idx
++) {
833 ct_read_lock_bh(idx
);
834 list_for_each_entry(cp
, &ip_vs_conn_tab
[idx
], c_list
) {
836 seq
->private = &ip_vs_conn_tab
[idx
];
840 ct_read_unlock_bh(idx
);
846 static void *ip_vs_conn_seq_start(struct seq_file
*seq
, loff_t
*pos
)
849 return *pos
? ip_vs_conn_array(seq
, *pos
- 1) :SEQ_START_TOKEN
;
852 static void *ip_vs_conn_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
854 struct ip_vs_conn
*cp
= v
;
855 struct list_head
*e
, *l
= seq
->private;
859 if (v
== SEQ_START_TOKEN
)
860 return ip_vs_conn_array(seq
, 0);
862 /* more on same hash chain? */
863 if ((e
= cp
->c_list
.next
) != l
)
864 return list_entry(e
, struct ip_vs_conn
, c_list
);
866 idx
= l
- ip_vs_conn_tab
;
867 ct_read_unlock_bh(idx
);
869 while (++idx
< ip_vs_conn_tab_size
) {
870 ct_read_lock_bh(idx
);
871 list_for_each_entry(cp
, &ip_vs_conn_tab
[idx
], c_list
) {
872 seq
->private = &ip_vs_conn_tab
[idx
];
875 ct_read_unlock_bh(idx
);
881 static void ip_vs_conn_seq_stop(struct seq_file
*seq
, void *v
)
883 struct list_head
*l
= seq
->private;
886 ct_read_unlock_bh(l
- ip_vs_conn_tab
);
889 static int ip_vs_conn_seq_show(struct seq_file
*seq
, void *v
)
892 if (v
== SEQ_START_TOKEN
)
894 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Expires\n");
896 const struct ip_vs_conn
*cp
= v
;
898 #ifdef CONFIG_IP_VS_IPV6
899 if (cp
->af
== AF_INET6
)
900 seq_printf(seq
, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %7lu\n",
901 ip_vs_proto_name(cp
->protocol
),
902 &cp
->caddr
.in6
, ntohs(cp
->cport
),
903 &cp
->vaddr
.in6
, ntohs(cp
->vport
),
904 &cp
->daddr
.in6
, ntohs(cp
->dport
),
905 ip_vs_state_name(cp
->protocol
, cp
->state
),
906 (cp
->timer
.expires
-jiffies
)/HZ
);
910 "%-3s %08X %04X %08X %04X"
911 " %08X %04X %-11s %7lu\n",
912 ip_vs_proto_name(cp
->protocol
),
913 ntohl(cp
->caddr
.ip
), ntohs(cp
->cport
),
914 ntohl(cp
->vaddr
.ip
), ntohs(cp
->vport
),
915 ntohl(cp
->daddr
.ip
), ntohs(cp
->dport
),
916 ip_vs_state_name(cp
->protocol
, cp
->state
),
917 (cp
->timer
.expires
-jiffies
)/HZ
);
922 static const struct seq_operations ip_vs_conn_seq_ops
= {
923 .start
= ip_vs_conn_seq_start
,
924 .next
= ip_vs_conn_seq_next
,
925 .stop
= ip_vs_conn_seq_stop
,
926 .show
= ip_vs_conn_seq_show
,
929 static int ip_vs_conn_open(struct inode
*inode
, struct file
*file
)
931 return seq_open(file
, &ip_vs_conn_seq_ops
);
934 static const struct file_operations ip_vs_conn_fops
= {
935 .owner
= THIS_MODULE
,
936 .open
= ip_vs_conn_open
,
939 .release
= seq_release
,
942 static const char *ip_vs_origin_name(unsigned flags
)
944 if (flags
& IP_VS_CONN_F_SYNC
)
950 static int ip_vs_conn_sync_seq_show(struct seq_file
*seq
, void *v
)
953 if (v
== SEQ_START_TOKEN
)
955 "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Origin Expires\n");
957 const struct ip_vs_conn
*cp
= v
;
959 #ifdef CONFIG_IP_VS_IPV6
960 if (cp
->af
== AF_INET6
)
961 seq_printf(seq
, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %-6s %7lu\n",
962 ip_vs_proto_name(cp
->protocol
),
963 &cp
->caddr
.in6
, ntohs(cp
->cport
),
964 &cp
->vaddr
.in6
, ntohs(cp
->vport
),
965 &cp
->daddr
.in6
, ntohs(cp
->dport
),
966 ip_vs_state_name(cp
->protocol
, cp
->state
),
967 ip_vs_origin_name(cp
->flags
),
968 (cp
->timer
.expires
-jiffies
)/HZ
);
972 "%-3s %08X %04X %08X %04X "
973 "%08X %04X %-11s %-6s %7lu\n",
974 ip_vs_proto_name(cp
->protocol
),
975 ntohl(cp
->caddr
.ip
), ntohs(cp
->cport
),
976 ntohl(cp
->vaddr
.ip
), ntohs(cp
->vport
),
977 ntohl(cp
->daddr
.ip
), ntohs(cp
->dport
),
978 ip_vs_state_name(cp
->protocol
, cp
->state
),
979 ip_vs_origin_name(cp
->flags
),
980 (cp
->timer
.expires
-jiffies
)/HZ
);
985 static const struct seq_operations ip_vs_conn_sync_seq_ops
= {
986 .start
= ip_vs_conn_seq_start
,
987 .next
= ip_vs_conn_seq_next
,
988 .stop
= ip_vs_conn_seq_stop
,
989 .show
= ip_vs_conn_sync_seq_show
,
992 static int ip_vs_conn_sync_open(struct inode
*inode
, struct file
*file
)
994 return seq_open(file
, &ip_vs_conn_sync_seq_ops
);
997 static const struct file_operations ip_vs_conn_sync_fops
= {
998 .owner
= THIS_MODULE
,
999 .open
= ip_vs_conn_sync_open
,
1001 .llseek
= seq_lseek
,
1002 .release
= seq_release
,
1009 * Randomly drop connection entries before running out of memory
1011 static inline int todrop_entry(struct ip_vs_conn
*cp
)
1014 * The drop rate array needs tuning for real environments.
1015 * Called from timer bh only => no locking
1017 static const char todrop_rate
[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
1018 static char todrop_counter
[9] = {0};
1021 /* if the conn entry hasn't lasted for 60 seconds, don't drop it.
1022 This will leave enough time for normal connection to get
1024 if (time_before(cp
->timeout
+ jiffies
, cp
->timer
.expires
+ 60*HZ
))
1027 /* Don't drop the entry if its number of incoming packets is not
1028 located in [0, 8] */
1029 i
= atomic_read(&cp
->in_pkts
);
1030 if (i
> 8 || i
< 0) return 0;
1032 if (!todrop_rate
[i
]) return 0;
1033 if (--todrop_counter
[i
] > 0) return 0;
1035 todrop_counter
[i
] = todrop_rate
[i
];
1039 /* Called from keventd and must protect itself from softirqs */
1040 void ip_vs_random_dropentry(void)
1043 struct ip_vs_conn
*cp
;
1046 * Randomly scan 1/32 of the whole table every second
1048 for (idx
= 0; idx
< (ip_vs_conn_tab_size
>>5); idx
++) {
1049 unsigned hash
= net_random() & ip_vs_conn_tab_mask
;
1052 * Lock is actually needed in this loop.
1054 ct_write_lock_bh(hash
);
1056 list_for_each_entry(cp
, &ip_vs_conn_tab
[hash
], c_list
) {
1057 if (cp
->flags
& IP_VS_CONN_F_TEMPLATE
)
1058 /* connection template */
1061 if (cp
->protocol
== IPPROTO_TCP
) {
1063 case IP_VS_TCP_S_SYN_RECV
:
1064 case IP_VS_TCP_S_SYNACK
:
1067 case IP_VS_TCP_S_ESTABLISHED
:
1068 if (todrop_entry(cp
))
1076 if (!todrop_entry(cp
))
1080 IP_VS_DBG(4, "del connection\n");
1081 ip_vs_conn_expire_now(cp
);
1083 IP_VS_DBG(4, "del conn template\n");
1084 ip_vs_conn_expire_now(cp
->control
);
1087 ct_write_unlock_bh(hash
);
1093 * Flush all the connection entries in the ip_vs_conn_tab
1095 static void ip_vs_conn_flush(void)
1098 struct ip_vs_conn
*cp
;
1101 for (idx
= 0; idx
< ip_vs_conn_tab_size
; idx
++) {
1103 * Lock is actually needed in this loop.
1105 ct_write_lock_bh(idx
);
1107 list_for_each_entry(cp
, &ip_vs_conn_tab
[idx
], c_list
) {
1109 IP_VS_DBG(4, "del connection\n");
1110 ip_vs_conn_expire_now(cp
);
1112 IP_VS_DBG(4, "del conn template\n");
1113 ip_vs_conn_expire_now(cp
->control
);
1116 ct_write_unlock_bh(idx
);
1119 /* the counter may be not NULL, because maybe some conn entries
1120 are run by slow timer handler or unhashed but still referred */
1121 if (atomic_read(&ip_vs_conn_count
) != 0) {
1128 int __init
ip_vs_conn_init(void)
1132 /* Compute size and mask */
1133 ip_vs_conn_tab_size
= 1 << ip_vs_conn_tab_bits
;
1134 ip_vs_conn_tab_mask
= ip_vs_conn_tab_size
- 1;
1137 * Allocate the connection hash table and initialize its list heads
1139 ip_vs_conn_tab
= vmalloc(ip_vs_conn_tab_size
*
1140 sizeof(struct list_head
));
1141 if (!ip_vs_conn_tab
)
1144 /* Allocate ip_vs_conn slab cache */
1145 ip_vs_conn_cachep
= kmem_cache_create("ip_vs_conn",
1146 sizeof(struct ip_vs_conn
), 0,
1147 SLAB_HWCACHE_ALIGN
, NULL
);
1148 if (!ip_vs_conn_cachep
) {
1149 vfree(ip_vs_conn_tab
);
1153 pr_info("Connection hash table configured "
1154 "(size=%d, memory=%ldKbytes)\n",
1155 ip_vs_conn_tab_size
,
1156 (long)(ip_vs_conn_tab_size
*sizeof(struct list_head
))/1024);
1157 IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n",
1158 sizeof(struct ip_vs_conn
));
1160 for (idx
= 0; idx
< ip_vs_conn_tab_size
; idx
++) {
1161 INIT_LIST_HEAD(&ip_vs_conn_tab
[idx
]);
1164 for (idx
= 0; idx
< CT_LOCKARRAY_SIZE
; idx
++) {
1165 rwlock_init(&__ip_vs_conntbl_lock_array
[idx
].l
);
1168 proc_net_fops_create(&init_net
, "ip_vs_conn", 0, &ip_vs_conn_fops
);
1169 proc_net_fops_create(&init_net
, "ip_vs_conn_sync", 0, &ip_vs_conn_sync_fops
);
1171 /* calculate the random value for connection hash */
1172 get_random_bytes(&ip_vs_conn_rnd
, sizeof(ip_vs_conn_rnd
));
1178 void ip_vs_conn_cleanup(void)
1180 /* flush all the connection entries first */
1183 /* Release the empty cache */
1184 kmem_cache_destroy(ip_vs_conn_cachep
);
1185 proc_net_remove(&init_net
, "ip_vs_conn");
1186 proc_net_remove(&init_net
, "ip_vs_conn_sync");
1187 vfree(ip_vs_conn_tab
);