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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
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 | |
6 | * cluster of servers. | |
7 | * | |
8 | * Version: $Id: ip_vs_conn.c,v 1.31 2003/04/18 09:03:16 wensong Exp $ | |
9 | * | |
10 | * Authors: Wensong Zhang <wensong@linuxvirtualserver.org> | |
11 | * Peter Kese <peter.kese@ijs.si> | |
12 | * Julian Anastasov <ja@ssi.bg> | |
13 | * | |
14 | * This program is free software; you can redistribute it and/or | |
15 | * modify it under the terms of the GNU General Public License | |
16 | * as published by the Free Software Foundation; either version | |
17 | * 2 of the License, or (at your option) any later version. | |
18 | * | |
19 | * The IPVS code for kernel 2.2 was done by Wensong Zhang and Peter Kese, | |
20 | * with changes/fixes from Julian Anastasov, Lars Marowsky-Bree, Horms | |
21 | * and others. Many code here is taken from IP MASQ code of kernel 2.2. | |
22 | * | |
23 | * Changes: | |
24 | * | |
25 | */ | |
26 | ||
e924283b | 27 | #include <linux/interrupt.h> |
14c85021 | 28 | #include <linux/in.h> |
f190055f | 29 | #include <linux/net.h> |
1da177e4 | 30 | #include <linux/kernel.h> |
14c85021 | 31 | #include <linux/module.h> |
1da177e4 LT |
32 | #include <linux/vmalloc.h> |
33 | #include <linux/proc_fs.h> /* for proc_net_* */ | |
34 | #include <linux/seq_file.h> | |
35 | #include <linux/jhash.h> | |
36 | #include <linux/random.h> | |
37 | ||
457c4cbc | 38 | #include <net/net_namespace.h> |
1da177e4 LT |
39 | #include <net/ip_vs.h> |
40 | ||
41 | ||
42 | /* | |
43 | * Connection hash table: for input and output packets lookups of IPVS | |
44 | */ | |
45 | static struct list_head *ip_vs_conn_tab; | |
46 | ||
47 | /* SLAB cache for IPVS connections */ | |
e18b890b | 48 | static struct kmem_cache *ip_vs_conn_cachep __read_mostly; |
1da177e4 LT |
49 | |
50 | /* counter for current IPVS connections */ | |
51 | static atomic_t ip_vs_conn_count = ATOMIC_INIT(0); | |
52 | ||
53 | /* counter for no client port connections */ | |
54 | static atomic_t ip_vs_conn_no_cport_cnt = ATOMIC_INIT(0); | |
55 | ||
56 | /* random value for IPVS connection hash */ | |
57 | static unsigned int ip_vs_conn_rnd; | |
58 | ||
59 | /* | |
60 | * Fine locking granularity for big connection hash table | |
61 | */ | |
62 | #define CT_LOCKARRAY_BITS 4 | |
63 | #define CT_LOCKARRAY_SIZE (1<<CT_LOCKARRAY_BITS) | |
64 | #define CT_LOCKARRAY_MASK (CT_LOCKARRAY_SIZE-1) | |
65 | ||
66 | struct ip_vs_aligned_lock | |
67 | { | |
68 | rwlock_t l; | |
69 | } __attribute__((__aligned__(SMP_CACHE_BYTES))); | |
70 | ||
71 | /* lock array for conn table */ | |
72 | static struct ip_vs_aligned_lock | |
73 | __ip_vs_conntbl_lock_array[CT_LOCKARRAY_SIZE] __cacheline_aligned; | |
74 | ||
75 | static inline void ct_read_lock(unsigned key) | |
76 | { | |
77 | read_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); | |
78 | } | |
79 | ||
80 | static inline void ct_read_unlock(unsigned key) | |
81 | { | |
82 | read_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); | |
83 | } | |
84 | ||
85 | static inline void ct_write_lock(unsigned key) | |
86 | { | |
87 | write_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); | |
88 | } | |
89 | ||
90 | static inline void ct_write_unlock(unsigned key) | |
91 | { | |
92 | write_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); | |
93 | } | |
94 | ||
95 | static inline void ct_read_lock_bh(unsigned key) | |
96 | { | |
97 | read_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); | |
98 | } | |
99 | ||
100 | static inline void ct_read_unlock_bh(unsigned key) | |
101 | { | |
102 | read_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); | |
103 | } | |
104 | ||
105 | static inline void ct_write_lock_bh(unsigned key) | |
106 | { | |
107 | write_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); | |
108 | } | |
109 | ||
110 | static inline void ct_write_unlock_bh(unsigned key) | |
111 | { | |
112 | write_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); | |
113 | } | |
114 | ||
115 | ||
116 | /* | |
117 | * Returns hash value for IPVS connection entry | |
118 | */ | |
014d730d | 119 | static unsigned int ip_vs_conn_hashkey(unsigned proto, __be32 addr, __be16 port) |
1da177e4 | 120 | { |
014d730d | 121 | return jhash_3words((__force u32)addr, (__force u32)port, proto, ip_vs_conn_rnd) |
1da177e4 LT |
122 | & IP_VS_CONN_TAB_MASK; |
123 | } | |
124 | ||
125 | ||
126 | /* | |
127 | * Hashes ip_vs_conn in ip_vs_conn_tab by proto,addr,port. | |
128 | * returns bool success. | |
129 | */ | |
130 | static inline int ip_vs_conn_hash(struct ip_vs_conn *cp) | |
131 | { | |
132 | unsigned hash; | |
133 | int ret; | |
134 | ||
135 | /* Hash by protocol, client address and port */ | |
136 | hash = ip_vs_conn_hashkey(cp->protocol, cp->caddr, cp->cport); | |
137 | ||
138 | ct_write_lock(hash); | |
139 | ||
140 | if (!(cp->flags & IP_VS_CONN_F_HASHED)) { | |
141 | list_add(&cp->c_list, &ip_vs_conn_tab[hash]); | |
142 | cp->flags |= IP_VS_CONN_F_HASHED; | |
143 | atomic_inc(&cp->refcnt); | |
144 | ret = 1; | |
145 | } else { | |
146 | IP_VS_ERR("ip_vs_conn_hash(): request for already hashed, " | |
147 | "called from %p\n", __builtin_return_address(0)); | |
148 | ret = 0; | |
149 | } | |
150 | ||
151 | ct_write_unlock(hash); | |
152 | ||
153 | return ret; | |
154 | } | |
155 | ||
156 | ||
157 | /* | |
158 | * UNhashes ip_vs_conn from ip_vs_conn_tab. | |
159 | * returns bool success. | |
160 | */ | |
161 | static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp) | |
162 | { | |
163 | unsigned hash; | |
164 | int ret; | |
165 | ||
166 | /* unhash it and decrease its reference counter */ | |
167 | hash = ip_vs_conn_hashkey(cp->protocol, cp->caddr, cp->cport); | |
168 | ||
169 | ct_write_lock(hash); | |
170 | ||
171 | if (cp->flags & IP_VS_CONN_F_HASHED) { | |
172 | list_del(&cp->c_list); | |
173 | cp->flags &= ~IP_VS_CONN_F_HASHED; | |
174 | atomic_dec(&cp->refcnt); | |
175 | ret = 1; | |
176 | } else | |
177 | ret = 0; | |
178 | ||
179 | ct_write_unlock(hash); | |
180 | ||
181 | return ret; | |
182 | } | |
183 | ||
184 | ||
185 | /* | |
186 | * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab. | |
187 | * Called for pkts coming from OUTside-to-INside. | |
188 | * s_addr, s_port: pkt source address (foreign host) | |
189 | * d_addr, d_port: pkt dest address (load balancer) | |
190 | */ | |
191 | static inline struct ip_vs_conn *__ip_vs_conn_in_get | |
014d730d | 192 | (int protocol, __be32 s_addr, __be16 s_port, __be32 d_addr, __be16 d_port) |
1da177e4 LT |
193 | { |
194 | unsigned hash; | |
195 | struct ip_vs_conn *cp; | |
196 | ||
197 | hash = ip_vs_conn_hashkey(protocol, s_addr, s_port); | |
198 | ||
199 | ct_read_lock(hash); | |
200 | ||
201 | list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) { | |
202 | if (s_addr==cp->caddr && s_port==cp->cport && | |
203 | d_port==cp->vport && d_addr==cp->vaddr && | |
87375ab4 | 204 | ((!s_port) ^ (!(cp->flags & IP_VS_CONN_F_NO_CPORT))) && |
1da177e4 LT |
205 | protocol==cp->protocol) { |
206 | /* HIT */ | |
207 | atomic_inc(&cp->refcnt); | |
208 | ct_read_unlock(hash); | |
209 | return cp; | |
210 | } | |
211 | } | |
212 | ||
213 | ct_read_unlock(hash); | |
214 | ||
215 | return NULL; | |
216 | } | |
217 | ||
218 | struct ip_vs_conn *ip_vs_conn_in_get | |
014d730d | 219 | (int protocol, __be32 s_addr, __be16 s_port, __be32 d_addr, __be16 d_port) |
1da177e4 LT |
220 | { |
221 | struct ip_vs_conn *cp; | |
222 | ||
223 | cp = __ip_vs_conn_in_get(protocol, s_addr, s_port, d_addr, d_port); | |
224 | if (!cp && atomic_read(&ip_vs_conn_no_cport_cnt)) | |
225 | cp = __ip_vs_conn_in_get(protocol, s_addr, 0, d_addr, d_port); | |
226 | ||
4b5bdf5c | 227 | IP_VS_DBG(9, "lookup/in %s %u.%u.%u.%u:%d->%u.%u.%u.%u:%d %s\n", |
1da177e4 LT |
228 | ip_vs_proto_name(protocol), |
229 | NIPQUAD(s_addr), ntohs(s_port), | |
230 | NIPQUAD(d_addr), ntohs(d_port), | |
231 | cp?"hit":"not hit"); | |
232 | ||
233 | return cp; | |
234 | } | |
235 | ||
87375ab4 JA |
236 | /* Get reference to connection template */ |
237 | struct ip_vs_conn *ip_vs_ct_in_get | |
014d730d | 238 | (int protocol, __be32 s_addr, __be16 s_port, __be32 d_addr, __be16 d_port) |
87375ab4 JA |
239 | { |
240 | unsigned hash; | |
241 | struct ip_vs_conn *cp; | |
242 | ||
243 | hash = ip_vs_conn_hashkey(protocol, s_addr, s_port); | |
244 | ||
245 | ct_read_lock(hash); | |
246 | ||
247 | list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) { | |
248 | if (s_addr==cp->caddr && s_port==cp->cport && | |
249 | d_port==cp->vport && d_addr==cp->vaddr && | |
250 | cp->flags & IP_VS_CONN_F_TEMPLATE && | |
251 | protocol==cp->protocol) { | |
252 | /* HIT */ | |
253 | atomic_inc(&cp->refcnt); | |
254 | goto out; | |
255 | } | |
256 | } | |
257 | cp = NULL; | |
258 | ||
259 | out: | |
260 | ct_read_unlock(hash); | |
261 | ||
4b5bdf5c | 262 | IP_VS_DBG(9, "template lookup/in %s %u.%u.%u.%u:%d->%u.%u.%u.%u:%d %s\n", |
87375ab4 JA |
263 | ip_vs_proto_name(protocol), |
264 | NIPQUAD(s_addr), ntohs(s_port), | |
265 | NIPQUAD(d_addr), ntohs(d_port), | |
266 | cp?"hit":"not hit"); | |
267 | ||
268 | return cp; | |
269 | } | |
1da177e4 LT |
270 | |
271 | /* | |
272 | * Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab. | |
273 | * Called for pkts coming from inside-to-OUTside. | |
274 | * s_addr, s_port: pkt source address (inside host) | |
275 | * d_addr, d_port: pkt dest address (foreign host) | |
276 | */ | |
277 | struct ip_vs_conn *ip_vs_conn_out_get | |
014d730d | 278 | (int protocol, __be32 s_addr, __be16 s_port, __be32 d_addr, __be16 d_port) |
1da177e4 LT |
279 | { |
280 | unsigned hash; | |
281 | struct ip_vs_conn *cp, *ret=NULL; | |
282 | ||
283 | /* | |
284 | * Check for "full" addressed entries | |
285 | */ | |
286 | hash = ip_vs_conn_hashkey(protocol, d_addr, d_port); | |
287 | ||
288 | ct_read_lock(hash); | |
289 | ||
290 | list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) { | |
291 | if (d_addr == cp->caddr && d_port == cp->cport && | |
292 | s_port == cp->dport && s_addr == cp->daddr && | |
293 | protocol == cp->protocol) { | |
294 | /* HIT */ | |
295 | atomic_inc(&cp->refcnt); | |
296 | ret = cp; | |
297 | break; | |
298 | } | |
299 | } | |
300 | ||
301 | ct_read_unlock(hash); | |
302 | ||
4b5bdf5c | 303 | IP_VS_DBG(9, "lookup/out %s %u.%u.%u.%u:%d->%u.%u.%u.%u:%d %s\n", |
1da177e4 LT |
304 | ip_vs_proto_name(protocol), |
305 | NIPQUAD(s_addr), ntohs(s_port), | |
306 | NIPQUAD(d_addr), ntohs(d_port), | |
307 | ret?"hit":"not hit"); | |
308 | ||
309 | return ret; | |
310 | } | |
311 | ||
312 | ||
313 | /* | |
314 | * Put back the conn and restart its timer with its timeout | |
315 | */ | |
316 | void ip_vs_conn_put(struct ip_vs_conn *cp) | |
317 | { | |
318 | /* reset it expire in its timeout */ | |
319 | mod_timer(&cp->timer, jiffies+cp->timeout); | |
320 | ||
321 | __ip_vs_conn_put(cp); | |
322 | } | |
323 | ||
324 | ||
325 | /* | |
326 | * Fill a no_client_port connection with a client port number | |
327 | */ | |
014d730d | 328 | void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport) |
1da177e4 LT |
329 | { |
330 | if (ip_vs_conn_unhash(cp)) { | |
331 | spin_lock(&cp->lock); | |
332 | if (cp->flags & IP_VS_CONN_F_NO_CPORT) { | |
333 | atomic_dec(&ip_vs_conn_no_cport_cnt); | |
334 | cp->flags &= ~IP_VS_CONN_F_NO_CPORT; | |
335 | cp->cport = cport; | |
336 | } | |
337 | spin_unlock(&cp->lock); | |
338 | ||
339 | /* hash on new dport */ | |
340 | ip_vs_conn_hash(cp); | |
341 | } | |
342 | } | |
343 | ||
344 | ||
345 | /* | |
346 | * Bind a connection entry with the corresponding packet_xmit. | |
347 | * Called by ip_vs_conn_new. | |
348 | */ | |
349 | static inline void ip_vs_bind_xmit(struct ip_vs_conn *cp) | |
350 | { | |
351 | switch (IP_VS_FWD_METHOD(cp)) { | |
352 | case IP_VS_CONN_F_MASQ: | |
353 | cp->packet_xmit = ip_vs_nat_xmit; | |
354 | break; | |
355 | ||
356 | case IP_VS_CONN_F_TUNNEL: | |
357 | cp->packet_xmit = ip_vs_tunnel_xmit; | |
358 | break; | |
359 | ||
360 | case IP_VS_CONN_F_DROUTE: | |
361 | cp->packet_xmit = ip_vs_dr_xmit; | |
362 | break; | |
363 | ||
364 | case IP_VS_CONN_F_LOCALNODE: | |
365 | cp->packet_xmit = ip_vs_null_xmit; | |
366 | break; | |
367 | ||
368 | case IP_VS_CONN_F_BYPASS: | |
369 | cp->packet_xmit = ip_vs_bypass_xmit; | |
370 | break; | |
371 | } | |
372 | } | |
373 | ||
374 | ||
375 | static inline int ip_vs_dest_totalconns(struct ip_vs_dest *dest) | |
376 | { | |
377 | return atomic_read(&dest->activeconns) | |
378 | + atomic_read(&dest->inactconns); | |
379 | } | |
380 | ||
381 | /* | |
382 | * Bind a connection entry with a virtual service destination | |
383 | * Called just after a new connection entry is created. | |
384 | */ | |
385 | static inline void | |
386 | ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest) | |
387 | { | |
388 | /* if dest is NULL, then return directly */ | |
389 | if (!dest) | |
390 | return; | |
391 | ||
392 | /* Increase the refcnt counter of the dest */ | |
393 | atomic_inc(&dest->refcnt); | |
394 | ||
395 | /* Bind with the destination and its corresponding transmitter */ | |
396 | cp->flags |= atomic_read(&dest->conn_flags); | |
397 | cp->dest = dest; | |
398 | ||
4b5bdf5c RN |
399 | IP_VS_DBG(7, "Bind-dest %s c:%u.%u.%u.%u:%d v:%u.%u.%u.%u:%d " |
400 | "d:%u.%u.%u.%u:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d " | |
401 | "dest->refcnt:%d\n", | |
1da177e4 LT |
402 | ip_vs_proto_name(cp->protocol), |
403 | NIPQUAD(cp->caddr), ntohs(cp->cport), | |
404 | NIPQUAD(cp->vaddr), ntohs(cp->vport), | |
405 | NIPQUAD(cp->daddr), ntohs(cp->dport), | |
406 | ip_vs_fwd_tag(cp), cp->state, | |
407 | cp->flags, atomic_read(&cp->refcnt), | |
408 | atomic_read(&dest->refcnt)); | |
409 | ||
410 | /* Update the connection counters */ | |
87375ab4 | 411 | if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) { |
1da177e4 LT |
412 | /* It is a normal connection, so increase the inactive |
413 | connection counter because it is in TCP SYNRECV | |
414 | state (inactive) or other protocol inacive state */ | |
415 | atomic_inc(&dest->inactconns); | |
416 | } else { | |
417 | /* It is a persistent connection/template, so increase | |
418 | the peristent connection counter */ | |
419 | atomic_inc(&dest->persistconns); | |
420 | } | |
421 | ||
422 | if (dest->u_threshold != 0 && | |
423 | ip_vs_dest_totalconns(dest) >= dest->u_threshold) | |
424 | dest->flags |= IP_VS_DEST_F_OVERLOAD; | |
425 | } | |
426 | ||
427 | ||
1e356f9c RB |
428 | /* |
429 | * Check if there is a destination for the connection, if so | |
430 | * bind the connection to the destination. | |
431 | */ | |
432 | struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp) | |
433 | { | |
434 | struct ip_vs_dest *dest; | |
435 | ||
436 | if ((cp) && (!cp->dest)) { | |
437 | dest = ip_vs_find_dest(cp->daddr, cp->dport, | |
438 | cp->vaddr, cp->vport, cp->protocol); | |
439 | ip_vs_bind_dest(cp, dest); | |
440 | return dest; | |
441 | } else | |
442 | return NULL; | |
443 | } | |
1e356f9c RB |
444 | |
445 | ||
1da177e4 LT |
446 | /* |
447 | * Unbind a connection entry with its VS destination | |
448 | * Called by the ip_vs_conn_expire function. | |
449 | */ | |
450 | static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp) | |
451 | { | |
452 | struct ip_vs_dest *dest = cp->dest; | |
453 | ||
454 | if (!dest) | |
455 | return; | |
456 | ||
4b5bdf5c RN |
457 | IP_VS_DBG(7, "Unbind-dest %s c:%u.%u.%u.%u:%d v:%u.%u.%u.%u:%d " |
458 | "d:%u.%u.%u.%u:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d " | |
459 | "dest->refcnt:%d\n", | |
1da177e4 LT |
460 | ip_vs_proto_name(cp->protocol), |
461 | NIPQUAD(cp->caddr), ntohs(cp->cport), | |
462 | NIPQUAD(cp->vaddr), ntohs(cp->vport), | |
463 | NIPQUAD(cp->daddr), ntohs(cp->dport), | |
464 | ip_vs_fwd_tag(cp), cp->state, | |
465 | cp->flags, atomic_read(&cp->refcnt), | |
466 | atomic_read(&dest->refcnt)); | |
467 | ||
468 | /* Update the connection counters */ | |
87375ab4 | 469 | if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) { |
1da177e4 LT |
470 | /* It is a normal connection, so decrease the inactconns |
471 | or activeconns counter */ | |
472 | if (cp->flags & IP_VS_CONN_F_INACTIVE) { | |
473 | atomic_dec(&dest->inactconns); | |
474 | } else { | |
475 | atomic_dec(&dest->activeconns); | |
476 | } | |
477 | } else { | |
478 | /* It is a persistent connection/template, so decrease | |
479 | the peristent connection counter */ | |
480 | atomic_dec(&dest->persistconns); | |
481 | } | |
482 | ||
483 | if (dest->l_threshold != 0) { | |
484 | if (ip_vs_dest_totalconns(dest) < dest->l_threshold) | |
485 | dest->flags &= ~IP_VS_DEST_F_OVERLOAD; | |
486 | } else if (dest->u_threshold != 0) { | |
487 | if (ip_vs_dest_totalconns(dest) * 4 < dest->u_threshold * 3) | |
488 | dest->flags &= ~IP_VS_DEST_F_OVERLOAD; | |
489 | } else { | |
490 | if (dest->flags & IP_VS_DEST_F_OVERLOAD) | |
491 | dest->flags &= ~IP_VS_DEST_F_OVERLOAD; | |
492 | } | |
493 | ||
494 | /* | |
495 | * Simply decrease the refcnt of the dest, because the | |
496 | * dest will be either in service's destination list | |
497 | * or in the trash. | |
498 | */ | |
499 | atomic_dec(&dest->refcnt); | |
500 | } | |
501 | ||
502 | ||
503 | /* | |
504 | * Checking if the destination of a connection template is available. | |
505 | * If available, return 1, otherwise invalidate this connection | |
506 | * template and return 0. | |
507 | */ | |
508 | int ip_vs_check_template(struct ip_vs_conn *ct) | |
509 | { | |
510 | struct ip_vs_dest *dest = ct->dest; | |
511 | ||
512 | /* | |
513 | * Checking the dest server status. | |
514 | */ | |
515 | if ((dest == NULL) || | |
e905a9ed YH |
516 | !(dest->flags & IP_VS_DEST_F_AVAILABLE) || |
517 | (sysctl_ip_vs_expire_quiescent_template && | |
1da177e4 LT |
518 | (atomic_read(&dest->weight) == 0))) { |
519 | IP_VS_DBG(9, "check_template: dest not available for " | |
520 | "protocol %s s:%u.%u.%u.%u:%d v:%u.%u.%u.%u:%d " | |
521 | "-> d:%u.%u.%u.%u:%d\n", | |
522 | ip_vs_proto_name(ct->protocol), | |
523 | NIPQUAD(ct->caddr), ntohs(ct->cport), | |
524 | NIPQUAD(ct->vaddr), ntohs(ct->vport), | |
525 | NIPQUAD(ct->daddr), ntohs(ct->dport)); | |
526 | ||
527 | /* | |
528 | * Invalidate the connection template | |
529 | */ | |
014d730d | 530 | if (ct->vport != htons(0xffff)) { |
1da177e4 | 531 | if (ip_vs_conn_unhash(ct)) { |
014d730d AV |
532 | ct->dport = htons(0xffff); |
533 | ct->vport = htons(0xffff); | |
1da177e4 LT |
534 | ct->cport = 0; |
535 | ip_vs_conn_hash(ct); | |
536 | } | |
537 | } | |
538 | ||
539 | /* | |
540 | * Simply decrease the refcnt of the template, | |
541 | * don't restart its timer. | |
542 | */ | |
543 | atomic_dec(&ct->refcnt); | |
544 | return 0; | |
545 | } | |
546 | return 1; | |
547 | } | |
548 | ||
549 | static void ip_vs_conn_expire(unsigned long data) | |
550 | { | |
551 | struct ip_vs_conn *cp = (struct ip_vs_conn *)data; | |
552 | ||
553 | cp->timeout = 60*HZ; | |
554 | ||
555 | /* | |
556 | * hey, I'm using it | |
557 | */ | |
558 | atomic_inc(&cp->refcnt); | |
559 | ||
560 | /* | |
561 | * do I control anybody? | |
562 | */ | |
563 | if (atomic_read(&cp->n_control)) | |
564 | goto expire_later; | |
565 | ||
566 | /* | |
567 | * unhash it if it is hashed in the conn table | |
568 | */ | |
569 | if (!ip_vs_conn_unhash(cp)) | |
570 | goto expire_later; | |
571 | ||
572 | /* | |
573 | * refcnt==1 implies I'm the only one referrer | |
574 | */ | |
575 | if (likely(atomic_read(&cp->refcnt) == 1)) { | |
576 | /* delete the timer if it is activated by other users */ | |
577 | if (timer_pending(&cp->timer)) | |
578 | del_timer(&cp->timer); | |
579 | ||
580 | /* does anybody control me? */ | |
581 | if (cp->control) | |
582 | ip_vs_control_del(cp); | |
583 | ||
584 | if (unlikely(cp->app != NULL)) | |
585 | ip_vs_unbind_app(cp); | |
586 | ip_vs_unbind_dest(cp); | |
587 | if (cp->flags & IP_VS_CONN_F_NO_CPORT) | |
588 | atomic_dec(&ip_vs_conn_no_cport_cnt); | |
589 | atomic_dec(&ip_vs_conn_count); | |
590 | ||
591 | kmem_cache_free(ip_vs_conn_cachep, cp); | |
592 | return; | |
593 | } | |
594 | ||
595 | /* hash it back to the table */ | |
596 | ip_vs_conn_hash(cp); | |
597 | ||
598 | expire_later: | |
4b5bdf5c | 599 | IP_VS_DBG(7, "delayed: conn->refcnt-1=%d conn->n_control=%d\n", |
1da177e4 LT |
600 | atomic_read(&cp->refcnt)-1, |
601 | atomic_read(&cp->n_control)); | |
602 | ||
603 | ip_vs_conn_put(cp); | |
604 | } | |
605 | ||
606 | ||
607 | void ip_vs_conn_expire_now(struct ip_vs_conn *cp) | |
608 | { | |
609 | if (del_timer(&cp->timer)) | |
610 | mod_timer(&cp->timer, jiffies); | |
1da177e4 LT |
611 | } |
612 | ||
613 | ||
614 | /* | |
615 | * Create a new connection entry and hash it into the ip_vs_conn_tab | |
616 | */ | |
617 | struct ip_vs_conn * | |
014d730d AV |
618 | ip_vs_conn_new(int proto, __be32 caddr, __be16 cport, __be32 vaddr, __be16 vport, |
619 | __be32 daddr, __be16 dport, unsigned flags, | |
1da177e4 LT |
620 | struct ip_vs_dest *dest) |
621 | { | |
622 | struct ip_vs_conn *cp; | |
623 | struct ip_vs_protocol *pp = ip_vs_proto_get(proto); | |
624 | ||
c3762229 | 625 | cp = kmem_cache_zalloc(ip_vs_conn_cachep, GFP_ATOMIC); |
1da177e4 LT |
626 | if (cp == NULL) { |
627 | IP_VS_ERR_RL("ip_vs_conn_new: no memory available.\n"); | |
628 | return NULL; | |
629 | } | |
630 | ||
1da177e4 | 631 | INIT_LIST_HEAD(&cp->c_list); |
b24b8a24 | 632 | setup_timer(&cp->timer, ip_vs_conn_expire, (unsigned long)cp); |
1da177e4 LT |
633 | cp->protocol = proto; |
634 | cp->caddr = caddr; | |
635 | cp->cport = cport; | |
636 | cp->vaddr = vaddr; | |
637 | cp->vport = vport; | |
638 | cp->daddr = daddr; | |
639 | cp->dport = dport; | |
640 | cp->flags = flags; | |
641 | spin_lock_init(&cp->lock); | |
642 | ||
643 | /* | |
644 | * Set the entry is referenced by the current thread before hashing | |
645 | * it in the table, so that other thread run ip_vs_random_dropentry | |
646 | * but cannot drop this entry. | |
647 | */ | |
648 | atomic_set(&cp->refcnt, 1); | |
649 | ||
650 | atomic_set(&cp->n_control, 0); | |
651 | atomic_set(&cp->in_pkts, 0); | |
652 | ||
653 | atomic_inc(&ip_vs_conn_count); | |
654 | if (flags & IP_VS_CONN_F_NO_CPORT) | |
655 | atomic_inc(&ip_vs_conn_no_cport_cnt); | |
656 | ||
657 | /* Bind the connection with a destination server */ | |
658 | ip_vs_bind_dest(cp, dest); | |
659 | ||
660 | /* Set its state and timeout */ | |
661 | cp->state = 0; | |
662 | cp->timeout = 3*HZ; | |
663 | ||
664 | /* Bind its packet transmitter */ | |
665 | ip_vs_bind_xmit(cp); | |
666 | ||
667 | if (unlikely(pp && atomic_read(&pp->appcnt))) | |
668 | ip_vs_bind_app(cp, pp); | |
669 | ||
670 | /* Hash it in the ip_vs_conn_tab finally */ | |
671 | ip_vs_conn_hash(cp); | |
672 | ||
673 | return cp; | |
674 | } | |
675 | ||
676 | ||
677 | /* | |
678 | * /proc/net/ip_vs_conn entries | |
679 | */ | |
680 | #ifdef CONFIG_PROC_FS | |
681 | ||
682 | static void *ip_vs_conn_array(struct seq_file *seq, loff_t pos) | |
683 | { | |
684 | int idx; | |
685 | struct ip_vs_conn *cp; | |
e905a9ed | 686 | |
1da177e4 LT |
687 | for(idx = 0; idx < IP_VS_CONN_TAB_SIZE; idx++) { |
688 | ct_read_lock_bh(idx); | |
689 | list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) { | |
690 | if (pos-- == 0) { | |
691 | seq->private = &ip_vs_conn_tab[idx]; | |
692 | return cp; | |
693 | } | |
694 | } | |
695 | ct_read_unlock_bh(idx); | |
696 | } | |
697 | ||
698 | return NULL; | |
699 | } | |
700 | ||
701 | static void *ip_vs_conn_seq_start(struct seq_file *seq, loff_t *pos) | |
702 | { | |
703 | seq->private = NULL; | |
704 | return *pos ? ip_vs_conn_array(seq, *pos - 1) :SEQ_START_TOKEN; | |
705 | } | |
706 | ||
707 | static void *ip_vs_conn_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
708 | { | |
709 | struct ip_vs_conn *cp = v; | |
710 | struct list_head *e, *l = seq->private; | |
711 | int idx; | |
712 | ||
713 | ++*pos; | |
e905a9ed | 714 | if (v == SEQ_START_TOKEN) |
1da177e4 LT |
715 | return ip_vs_conn_array(seq, 0); |
716 | ||
717 | /* more on same hash chain? */ | |
718 | if ((e = cp->c_list.next) != l) | |
719 | return list_entry(e, struct ip_vs_conn, c_list); | |
720 | ||
721 | idx = l - ip_vs_conn_tab; | |
722 | ct_read_unlock_bh(idx); | |
723 | ||
724 | while (++idx < IP_VS_CONN_TAB_SIZE) { | |
725 | ct_read_lock_bh(idx); | |
726 | list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) { | |
727 | seq->private = &ip_vs_conn_tab[idx]; | |
728 | return cp; | |
e905a9ed | 729 | } |
1da177e4 LT |
730 | ct_read_unlock_bh(idx); |
731 | } | |
732 | seq->private = NULL; | |
733 | return NULL; | |
734 | } | |
735 | ||
736 | static void ip_vs_conn_seq_stop(struct seq_file *seq, void *v) | |
737 | { | |
738 | struct list_head *l = seq->private; | |
739 | ||
740 | if (l) | |
741 | ct_read_unlock_bh(l - ip_vs_conn_tab); | |
742 | } | |
743 | ||
744 | static int ip_vs_conn_seq_show(struct seq_file *seq, void *v) | |
745 | { | |
746 | ||
747 | if (v == SEQ_START_TOKEN) | |
748 | seq_puts(seq, | |
749 | "Pro FromIP FPrt ToIP TPrt DestIP DPrt State Expires\n"); | |
750 | else { | |
751 | const struct ip_vs_conn *cp = v; | |
752 | ||
753 | seq_printf(seq, | |
754 | "%-3s %08X %04X %08X %04X %08X %04X %-11s %7lu\n", | |
755 | ip_vs_proto_name(cp->protocol), | |
756 | ntohl(cp->caddr), ntohs(cp->cport), | |
757 | ntohl(cp->vaddr), ntohs(cp->vport), | |
758 | ntohl(cp->daddr), ntohs(cp->dport), | |
759 | ip_vs_state_name(cp->protocol, cp->state), | |
760 | (cp->timer.expires-jiffies)/HZ); | |
761 | } | |
762 | return 0; | |
763 | } | |
764 | ||
56b3d975 | 765 | static const struct seq_operations ip_vs_conn_seq_ops = { |
1da177e4 LT |
766 | .start = ip_vs_conn_seq_start, |
767 | .next = ip_vs_conn_seq_next, | |
768 | .stop = ip_vs_conn_seq_stop, | |
769 | .show = ip_vs_conn_seq_show, | |
770 | }; | |
771 | ||
772 | static int ip_vs_conn_open(struct inode *inode, struct file *file) | |
773 | { | |
774 | return seq_open(file, &ip_vs_conn_seq_ops); | |
775 | } | |
776 | ||
9a32144e | 777 | static const struct file_operations ip_vs_conn_fops = { |
1da177e4 LT |
778 | .owner = THIS_MODULE, |
779 | .open = ip_vs_conn_open, | |
780 | .read = seq_read, | |
781 | .llseek = seq_lseek, | |
782 | .release = seq_release, | |
783 | }; | |
784 | #endif | |
785 | ||
786 | ||
787 | /* | |
788 | * Randomly drop connection entries before running out of memory | |
789 | */ | |
790 | static inline int todrop_entry(struct ip_vs_conn *cp) | |
791 | { | |
792 | /* | |
793 | * The drop rate array needs tuning for real environments. | |
794 | * Called from timer bh only => no locking | |
795 | */ | |
9b5b5cff | 796 | static const char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8}; |
1da177e4 LT |
797 | static char todrop_counter[9] = {0}; |
798 | int i; | |
799 | ||
800 | /* if the conn entry hasn't lasted for 60 seconds, don't drop it. | |
801 | This will leave enough time for normal connection to get | |
802 | through. */ | |
803 | if (time_before(cp->timeout + jiffies, cp->timer.expires + 60*HZ)) | |
804 | return 0; | |
805 | ||
806 | /* Don't drop the entry if its number of incoming packets is not | |
807 | located in [0, 8] */ | |
808 | i = atomic_read(&cp->in_pkts); | |
809 | if (i > 8 || i < 0) return 0; | |
810 | ||
811 | if (!todrop_rate[i]) return 0; | |
812 | if (--todrop_counter[i] > 0) return 0; | |
813 | ||
814 | todrop_counter[i] = todrop_rate[i]; | |
815 | return 1; | |
816 | } | |
817 | ||
af9debd4 | 818 | /* Called from keventd and must protect itself from softirqs */ |
1da177e4 LT |
819 | void ip_vs_random_dropentry(void) |
820 | { | |
821 | int idx; | |
822 | struct ip_vs_conn *cp; | |
1da177e4 LT |
823 | |
824 | /* | |
825 | * Randomly scan 1/32 of the whole table every second | |
826 | */ | |
827 | for (idx = 0; idx < (IP_VS_CONN_TAB_SIZE>>5); idx++) { | |
828 | unsigned hash = net_random() & IP_VS_CONN_TAB_MASK; | |
829 | ||
830 | /* | |
831 | * Lock is actually needed in this loop. | |
832 | */ | |
af9debd4 | 833 | ct_write_lock_bh(hash); |
1da177e4 LT |
834 | |
835 | list_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) { | |
87375ab4 | 836 | if (cp->flags & IP_VS_CONN_F_TEMPLATE) |
1da177e4 LT |
837 | /* connection template */ |
838 | continue; | |
839 | ||
840 | if (cp->protocol == IPPROTO_TCP) { | |
841 | switch(cp->state) { | |
842 | case IP_VS_TCP_S_SYN_RECV: | |
843 | case IP_VS_TCP_S_SYNACK: | |
844 | break; | |
845 | ||
846 | case IP_VS_TCP_S_ESTABLISHED: | |
847 | if (todrop_entry(cp)) | |
848 | break; | |
849 | continue; | |
850 | ||
851 | default: | |
852 | continue; | |
853 | } | |
854 | } else { | |
855 | if (!todrop_entry(cp)) | |
856 | continue; | |
857 | } | |
858 | ||
1da177e4 LT |
859 | IP_VS_DBG(4, "del connection\n"); |
860 | ip_vs_conn_expire_now(cp); | |
fb3d8949 | 861 | if (cp->control) { |
1da177e4 | 862 | IP_VS_DBG(4, "del conn template\n"); |
fb3d8949 | 863 | ip_vs_conn_expire_now(cp->control); |
1da177e4 | 864 | } |
1da177e4 | 865 | } |
af9debd4 | 866 | ct_write_unlock_bh(hash); |
1da177e4 LT |
867 | } |
868 | } | |
869 | ||
870 | ||
871 | /* | |
872 | * Flush all the connection entries in the ip_vs_conn_tab | |
873 | */ | |
874 | static void ip_vs_conn_flush(void) | |
875 | { | |
876 | int idx; | |
877 | struct ip_vs_conn *cp; | |
1da177e4 LT |
878 | |
879 | flush_again: | |
880 | for (idx=0; idx<IP_VS_CONN_TAB_SIZE; idx++) { | |
881 | /* | |
882 | * Lock is actually needed in this loop. | |
883 | */ | |
884 | ct_write_lock_bh(idx); | |
885 | ||
886 | list_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) { | |
1da177e4 | 887 | |
1da177e4 LT |
888 | IP_VS_DBG(4, "del connection\n"); |
889 | ip_vs_conn_expire_now(cp); | |
fb3d8949 | 890 | if (cp->control) { |
1da177e4 | 891 | IP_VS_DBG(4, "del conn template\n"); |
fb3d8949 | 892 | ip_vs_conn_expire_now(cp->control); |
1da177e4 | 893 | } |
1da177e4 LT |
894 | } |
895 | ct_write_unlock_bh(idx); | |
896 | } | |
897 | ||
898 | /* the counter may be not NULL, because maybe some conn entries | |
899 | are run by slow timer handler or unhashed but still referred */ | |
900 | if (atomic_read(&ip_vs_conn_count) != 0) { | |
901 | schedule(); | |
902 | goto flush_again; | |
903 | } | |
904 | } | |
905 | ||
906 | ||
907 | int ip_vs_conn_init(void) | |
908 | { | |
909 | int idx; | |
910 | ||
911 | /* | |
912 | * Allocate the connection hash table and initialize its list heads | |
913 | */ | |
914 | ip_vs_conn_tab = vmalloc(IP_VS_CONN_TAB_SIZE*sizeof(struct list_head)); | |
915 | if (!ip_vs_conn_tab) | |
916 | return -ENOMEM; | |
917 | ||
918 | /* Allocate ip_vs_conn slab cache */ | |
919 | ip_vs_conn_cachep = kmem_cache_create("ip_vs_conn", | |
920 | sizeof(struct ip_vs_conn), 0, | |
20c2df83 | 921 | SLAB_HWCACHE_ALIGN, NULL); |
1da177e4 LT |
922 | if (!ip_vs_conn_cachep) { |
923 | vfree(ip_vs_conn_tab); | |
924 | return -ENOMEM; | |
925 | } | |
926 | ||
927 | IP_VS_INFO("Connection hash table configured " | |
928 | "(size=%d, memory=%ldKbytes)\n", | |
929 | IP_VS_CONN_TAB_SIZE, | |
930 | (long)(IP_VS_CONN_TAB_SIZE*sizeof(struct list_head))/1024); | |
931 | IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n", | |
932 | sizeof(struct ip_vs_conn)); | |
933 | ||
934 | for (idx = 0; idx < IP_VS_CONN_TAB_SIZE; idx++) { | |
935 | INIT_LIST_HEAD(&ip_vs_conn_tab[idx]); | |
936 | } | |
937 | ||
938 | for (idx = 0; idx < CT_LOCKARRAY_SIZE; idx++) { | |
939 | rwlock_init(&__ip_vs_conntbl_lock_array[idx].l); | |
940 | } | |
941 | ||
457c4cbc | 942 | proc_net_fops_create(&init_net, "ip_vs_conn", 0, &ip_vs_conn_fops); |
1da177e4 LT |
943 | |
944 | /* calculate the random value for connection hash */ | |
945 | get_random_bytes(&ip_vs_conn_rnd, sizeof(ip_vs_conn_rnd)); | |
946 | ||
947 | return 0; | |
948 | } | |
949 | ||
950 | ||
951 | void ip_vs_conn_cleanup(void) | |
952 | { | |
953 | /* flush all the connection entries first */ | |
954 | ip_vs_conn_flush(); | |
955 | ||
956 | /* Release the empty cache */ | |
957 | kmem_cache_destroy(ip_vs_conn_cachep); | |
457c4cbc | 958 | proc_net_remove(&init_net, "ip_vs_conn"); |
1da177e4 LT |
959 | vfree(ip_vs_conn_tab); |
960 | } |