net/netfilter/ipvs/ip_vs_conn.c

   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  * Authors:     Wensong Zhang <wensong@linuxvirtualserver.org>
   9  *              Peter Kese <peter.kese@ijs.si>
  10  *              Julian Anastasov <ja@ssi.bg>
  11  *
  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.
  16  *
  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.
  20  *
  21  * Changes:
  22  *
  23  */
  24
  25 #define KMSG_COMPONENT "IPVS"
  26 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  27
  28 #include <linux/interrupt.h>
  29 #include <linux/in.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>
  39
  40 #include <net/net_namespace.h>
  41 #include <net/ip_vs.h>
  42
  43
  44 #ifndef CONFIG_IP_VS_TAB_BITS
  45 #define CONFIG_IP_VS_TAB_BITS   12
  46 #endif
  47
  48 /*
  49  * Connection hash size. Default is what was selected at compile time.
  50 */
  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");
  54
  55 /* size and mask values */
  56 int ip_vs_conn_tab_size __read_mostly;
  57 static int ip_vs_conn_tab_mask __read_mostly;
  58
  59 /*
  60  *  Connection hash table: for input and output packets lookups of IPVS
  61  */
  62 static struct hlist_head *ip_vs_conn_tab __read_mostly;
  63
  64 /*  SLAB cache for IPVS connections */
  65 static struct kmem_cache *ip_vs_conn_cachep __read_mostly;
  66
  67 /*  counter for no client port connections */
  68 static atomic_t ip_vs_conn_no_cport_cnt = ATOMIC_INIT(0);
  69
  70 /* random value for IPVS connection hash */
  71 static unsigned int ip_vs_conn_rnd __read_mostly;
  72
  73 /*
  74  *  Fine locking granularity for big connection hash table
  75  */
  76 #define CT_LOCKARRAY_BITS  5
  77 #define CT_LOCKARRAY_SIZE  (1<<CT_LOCKARRAY_BITS)
  78 #define CT_LOCKARRAY_MASK  (CT_LOCKARRAY_SIZE-1)
  79
  80 struct ip_vs_aligned_lock
  81 {
  82         rwlock_t        l;
  83 } __attribute__((__aligned__(SMP_CACHE_BYTES)));
  84
  85 /* lock array for conn table */
  86 static struct ip_vs_aligned_lock
  87 __ip_vs_conntbl_lock_array[CT_LOCKARRAY_SIZE] __cacheline_aligned;
  88
  89 static inline void ct_read_lock(unsigned int key)
  90 {
  91         read_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
  92 }
  93
  94 static inline void ct_read_unlock(unsigned int key)
  95 {
  96         read_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
  97 }
  98
  99 static inline void ct_write_lock(unsigned int key)
 100 {
 101         write_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
 102 }
 103
 104 static inline void ct_write_unlock(unsigned int key)
 105 {
 106         write_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
 107 }
 108
 109 static inline void ct_read_lock_bh(unsigned int key)
 110 {
 111         read_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
 112 }
 113
 114 static inline void ct_read_unlock_bh(unsigned int key)
 115 {
 116         read_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
 117 }
 118
 119 static inline void ct_write_lock_bh(unsigned int key)
 120 {
 121         write_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
 122 }
 123
 124 static inline void ct_write_unlock_bh(unsigned int key)
 125 {
 126         write_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l);
 127 }
 128
 129
 130 /*
 131  *      Returns hash value for IPVS connection entry
 132  */
 133 static unsigned int ip_vs_conn_hashkey(struct net *net, int af, unsigned int proto,
 134                                        const union nf_inet_addr *addr,
 135                                        __be16 port)
 136 {
 137 #ifdef CONFIG_IP_VS_IPV6
 138         if (af == AF_INET6)
 139                 return (jhash_3words(jhash(addr, 16, ip_vs_conn_rnd),
 140                                     (__force u32)port, proto, ip_vs_conn_rnd) ^
 141                         ((size_t)net>>8)) & ip_vs_conn_tab_mask;
 142 #endif
 143         return (jhash_3words((__force u32)addr->ip, (__force u32)port, proto,
 144                             ip_vs_conn_rnd) ^
 145                 ((size_t)net>>8)) & ip_vs_conn_tab_mask;
 146 }
 147
 148 static unsigned int ip_vs_conn_hashkey_param(const struct ip_vs_conn_param *p,
 149                                              bool inverse)
 150 {
 151         const union nf_inet_addr *addr;
 152         __be16 port;
 153
 154         if (p->pe_data && p->pe->hashkey_raw)
 155                 return p->pe->hashkey_raw(p, ip_vs_conn_rnd, inverse) &
 156                         ip_vs_conn_tab_mask;
 157
 158         if (likely(!inverse)) {
 159                 addr = p->caddr;
 160                 port = p->cport;
 161         } else {
 162                 addr = p->vaddr;
 163                 port = p->vport;
 164         }
 165
 166         return ip_vs_conn_hashkey(p->net, p->af, p->protocol, addr, port);
 167 }
 168
 169 static unsigned int ip_vs_conn_hashkey_conn(const struct ip_vs_conn *cp)
 170 {
 171         struct ip_vs_conn_param p;
 172
 173         ip_vs_conn_fill_param(ip_vs_conn_net(cp), cp->af, cp->protocol,
 174                               &cp->caddr, cp->cport, NULL, 0, &p);
 175
 176         if (cp->pe) {
 177                 p.pe = cp->pe;
 178                 p.pe_data = cp->pe_data;
 179                 p.pe_data_len = cp->pe_data_len;
 180         }
 181
 182         return ip_vs_conn_hashkey_param(&p, false);
 183 }
 184
 185 /*
 186  *      Hashes ip_vs_conn in ip_vs_conn_tab by netns,proto,addr,port.
 187  *      returns bool success.
 188  */
 189 static inline int ip_vs_conn_hash(struct ip_vs_conn *cp)
 190 {
 191         unsigned int hash;
 192         int ret;
 193
 194         if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
 195                 return 0;
 196
 197         /* Hash by protocol, client address and port */
 198         hash = ip_vs_conn_hashkey_conn(cp);
 199
 200         ct_write_lock(hash);
 201         spin_lock(&cp->lock);
 202
 203         if (!(cp->flags & IP_VS_CONN_F_HASHED)) {
 204                 hlist_add_head(&cp->c_list, &ip_vs_conn_tab[hash]);
 205                 cp->flags |= IP_VS_CONN_F_HASHED;
 206                 atomic_inc(&cp->refcnt);
 207                 ret = 1;
 208         } else {
 209                 pr_err("%s(): request for already hashed, called from %pF\n",
 210                        __func__, __builtin_return_address(0));
 211                 ret = 0;
 212         }
 213
 214         spin_unlock(&cp->lock);
 215         ct_write_unlock(hash);
 216
 217         return ret;
 218 }
 219
 220
 221 /*
 222  *      UNhashes ip_vs_conn from ip_vs_conn_tab.
 223  *      returns bool success.
 224  */
 225 static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp)
 226 {
 227         unsigned int hash;
 228         int ret;
 229
 230         /* unhash it and decrease its reference counter */
 231         hash = ip_vs_conn_hashkey_conn(cp);
 232
 233         ct_write_lock(hash);
 234         spin_lock(&cp->lock);
 235
 236         if (cp->flags & IP_VS_CONN_F_HASHED) {
 237                 hlist_del(&cp->c_list);
 238                 cp->flags &= ~IP_VS_CONN_F_HASHED;
 239                 atomic_dec(&cp->refcnt);
 240                 ret = 1;
 241         } else
 242                 ret = 0;
 243
 244         spin_unlock(&cp->lock);
 245         ct_write_unlock(hash);
 246
 247         return ret;
 248 }
 249
 250
 251 /*
 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)
 256  */
 257 static inline struct ip_vs_conn *
 258 __ip_vs_conn_in_get(const struct ip_vs_conn_param *p)
 259 {
 260         unsigned int hash;
 261         struct ip_vs_conn *cp;
 262
 263         hash = ip_vs_conn_hashkey_param(p, false);
 264
 265         ct_read_lock(hash);
 266
 267         hlist_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
 268                 if (cp->af == p->af &&
 269                     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                         /* HIT */
 276                         atomic_inc(&cp->refcnt);
 277                         ct_read_unlock(hash);
 278                         return cp;
 279                 }
 280         }
 281
 282         ct_read_unlock(hash);
 283
 284         return NULL;
 285 }
 286
 287 struct ip_vs_conn *ip_vs_conn_in_get(const struct ip_vs_conn_param *p)
 288 {
 289         struct ip_vs_conn *cp;
 290
 291         cp = __ip_vs_conn_in_get(p);
 292         if (!cp && atomic_read(&ip_vs_conn_no_cport_cnt)) {
 293                 struct ip_vs_conn_param cport_zero_p = *p;
 294                 cport_zero_p.cport = 0;
 295                 cp = __ip_vs_conn_in_get(&cport_zero_p);
 296         }
 297
 298         IP_VS_DBG_BUF(9, "lookup/in %s %s:%d->%s:%d %s\n",
 299                       ip_vs_proto_name(p->protocol),
 300                       IP_VS_DBG_ADDR(p->af, p->caddr), ntohs(p->cport),
 301                       IP_VS_DBG_ADDR(p->af, p->vaddr), ntohs(p->vport),
 302                       cp ? "hit" : "not hit");
 303
 304         return cp;
 305 }
 306
 307 static int
 308 ip_vs_conn_fill_param_proto(int af, const struct sk_buff *skb,
 309                             const struct ip_vs_iphdr *iph,
 310                             int inverse, struct ip_vs_conn_param *p)
 311 {
 312         __be16 _ports[2], *pptr;
 313         struct net *net = skb_net(skb);
 314
 315         pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports, iph);
 316         if (pptr == NULL)
 317                 return 1;
 318
 319         if (likely(!inverse))
 320                 ip_vs_conn_fill_param(net, af, iph->protocol, &iph->saddr,
 321                                       pptr[0], &iph->daddr, pptr[1], p);
 322         else
 323                 ip_vs_conn_fill_param(net, af, iph->protocol, &iph->daddr,
 324                                       pptr[1], &iph->saddr, pptr[0], p);
 325         return 0;
 326 }
 327
 328 struct ip_vs_conn *
 329 ip_vs_conn_in_get_proto(int af, const struct sk_buff *skb,
 330                         const struct ip_vs_iphdr *iph, int inverse)
 331 {
 332         struct ip_vs_conn_param p;
 333
 334         if (ip_vs_conn_fill_param_proto(af, skb, iph, inverse, &p))
 335                 return NULL;
 336
 337         return ip_vs_conn_in_get(&p);
 338 }
 339 EXPORT_SYMBOL_GPL(ip_vs_conn_in_get_proto);
 340
 341 /* Get reference to connection template */
 342 struct ip_vs_conn *ip_vs_ct_in_get(const struct ip_vs_conn_param *p)
 343 {
 344         unsigned int hash;
 345         struct ip_vs_conn *cp;
 346
 347         hash = ip_vs_conn_hashkey_param(p, false);
 348
 349         ct_read_lock(hash);
 350
 351         hlist_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
 352                 if (!ip_vs_conn_net_eq(cp, p->net))
 353                         continue;
 354                 if (p->pe_data && p->pe->ct_match) {
 355                         if (p->pe == cp->pe && p->pe->ct_match(p, cp))
 356                                 goto out;
 357                         continue;
 358                 }
 359
 360                 if (cp->af == p->af &&
 361                     ip_vs_addr_equal(p->af, p->caddr, &cp->caddr) &&
 362                     /* protocol should only be IPPROTO_IP if
 363                      * p->vaddr is a fwmark */
 364                     ip_vs_addr_equal(p->protocol == IPPROTO_IP ? AF_UNSPEC :
 365                                      p->af, p->vaddr, &cp->vaddr) &&
 366                     p->cport == cp->cport && p->vport == cp->vport &&
 367                     cp->flags & IP_VS_CONN_F_TEMPLATE &&
 368                     p->protocol == cp->protocol)
 369                         goto out;
 370         }
 371         cp = NULL;
 372
 373   out:
 374         if (cp)
 375                 atomic_inc(&cp->refcnt);
 376         ct_read_unlock(hash);
 377
 378         IP_VS_DBG_BUF(9, "template lookup/in %s %s:%d->%s:%d %s\n",
 379                       ip_vs_proto_name(p->protocol),
 380                       IP_VS_DBG_ADDR(p->af, p->caddr), ntohs(p->cport),
 381                       IP_VS_DBG_ADDR(p->af, p->vaddr), ntohs(p->vport),
 382                       cp ? "hit" : "not hit");
 383
 384         return cp;
 385 }
 386
 387 /* Gets ip_vs_conn associated with supplied parameters in the ip_vs_conn_tab.
 388  * Called for pkts coming from inside-to-OUTside.
 389  *      p->caddr, p->cport: pkt source address (inside host)
 390  *      p->vaddr, p->vport: pkt dest address (foreign host) */
 391 struct ip_vs_conn *ip_vs_conn_out_get(const struct ip_vs_conn_param *p)
 392 {
 393         unsigned int hash;
 394         struct ip_vs_conn *cp, *ret=NULL;
 395
 396         /*
 397          *      Check for "full" addressed entries
 398          */
 399         hash = ip_vs_conn_hashkey_param(p, true);
 400
 401         ct_read_lock(hash);
 402
 403         hlist_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
 404                 if (cp->af == p->af &&
 405                     p->vport == cp->cport && p->cport == cp->dport &&
 406                     ip_vs_addr_equal(p->af, p->vaddr, &cp->caddr) &&
 407                     ip_vs_addr_equal(p->af, p->caddr, &cp->daddr) &&
 408                     p->protocol == cp->protocol &&
 409                     ip_vs_conn_net_eq(cp, p->net)) {
 410                         /* HIT */
 411                         atomic_inc(&cp->refcnt);
 412                         ret = cp;
 413                         break;
 414                 }
 415         }
 416
 417         ct_read_unlock(hash);
 418
 419         IP_VS_DBG_BUF(9, "lookup/out %s %s:%d->%s:%d %s\n",
 420                       ip_vs_proto_name(p->protocol),
 421                       IP_VS_DBG_ADDR(p->af, p->caddr), ntohs(p->cport),
 422                       IP_VS_DBG_ADDR(p->af, p->vaddr), ntohs(p->vport),
 423                       ret ? "hit" : "not hit");
 424
 425         return ret;
 426 }
 427
 428 struct ip_vs_conn *
 429 ip_vs_conn_out_get_proto(int af, const struct sk_buff *skb,
 430                          const struct ip_vs_iphdr *iph, int inverse)
 431 {
 432         struct ip_vs_conn_param p;
 433
 434         if (ip_vs_conn_fill_param_proto(af, skb, iph, inverse, &p))
 435                 return NULL;
 436
 437         return ip_vs_conn_out_get(&p);
 438 }
 439 EXPORT_SYMBOL_GPL(ip_vs_conn_out_get_proto);
 440
 441 /*
 442  *      Put back the conn and restart its timer with its timeout
 443  */
 444 void ip_vs_conn_put(struct ip_vs_conn *cp)
 445 {
 446         unsigned long t = (cp->flags & IP_VS_CONN_F_ONE_PACKET) ?
 447                 0 : cp->timeout;
 448         mod_timer(&cp->timer, jiffies+t);
 449
 450         __ip_vs_conn_put(cp);
 451 }
 452
 453
 454 /*
 455  *      Fill a no_client_port connection with a client port number
 456  */
 457 void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport)
 458 {
 459         if (ip_vs_conn_unhash(cp)) {
 460                 spin_lock(&cp->lock);
 461                 if (cp->flags & IP_VS_CONN_F_NO_CPORT) {
 462                         atomic_dec(&ip_vs_conn_no_cport_cnt);
 463                         cp->flags &= ~IP_VS_CONN_F_NO_CPORT;
 464                         cp->cport = cport;
 465                 }
 466                 spin_unlock(&cp->lock);
 467
 468                 /* hash on new dport */
 469                 ip_vs_conn_hash(cp);
 470         }
 471 }
 472
 473
 474 /*
 475  *      Bind a connection entry with the corresponding packet_xmit.
 476  *      Called by ip_vs_conn_new.
 477  */
 478 static inline void ip_vs_bind_xmit(struct ip_vs_conn *cp)
 479 {
 480         switch (IP_VS_FWD_METHOD(cp)) {
 481         case IP_VS_CONN_F_MASQ:
 482                 cp->packet_xmit = ip_vs_nat_xmit;
 483                 break;
 484
 485         case IP_VS_CONN_F_TUNNEL:
 486                 cp->packet_xmit = ip_vs_tunnel_xmit;
 487                 break;
 488
 489         case IP_VS_CONN_F_DROUTE:
 490                 cp->packet_xmit = ip_vs_dr_xmit;
 491                 break;
 492
 493         case IP_VS_CONN_F_LOCALNODE:
 494                 cp->packet_xmit = ip_vs_null_xmit;
 495                 break;
 496
 497         case IP_VS_CONN_F_BYPASS:
 498                 cp->packet_xmit = ip_vs_bypass_xmit;
 499                 break;
 500         }
 501 }
 502
 503 #ifdef CONFIG_IP_VS_IPV6
 504 static inline void ip_vs_bind_xmit_v6(struct ip_vs_conn *cp)
 505 {
 506         switch (IP_VS_FWD_METHOD(cp)) {
 507         case IP_VS_CONN_F_MASQ:
 508                 cp->packet_xmit = ip_vs_nat_xmit_v6;
 509                 break;
 510
 511         case IP_VS_CONN_F_TUNNEL:
 512                 cp->packet_xmit = ip_vs_tunnel_xmit_v6;
 513                 break;
 514
 515         case IP_VS_CONN_F_DROUTE:
 516                 cp->packet_xmit = ip_vs_dr_xmit_v6;
 517                 break;
 518
 519         case IP_VS_CONN_F_LOCALNODE:
 520                 cp->packet_xmit = ip_vs_null_xmit;
 521                 break;
 522
 523         case IP_VS_CONN_F_BYPASS:
 524                 cp->packet_xmit = ip_vs_bypass_xmit_v6;
 525                 break;
 526         }
 527 }
 528 #endif
 529
 530
 531 static inline int ip_vs_dest_totalconns(struct ip_vs_dest *dest)
 532 {
 533         return atomic_read(&dest->activeconns)
 534                 + atomic_read(&dest->inactconns);
 535 }
 536
 537 /*
 538  *      Bind a connection entry with a virtual service destination
 539  *      Called just after a new connection entry is created.
 540  */
 541 static inline void
 542 ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
 543 {
 544         unsigned int conn_flags;
 545         __u32 flags;
 546
 547         /* if dest is NULL, then return directly */
 548         if (!dest)
 549                 return;
 550
 551         /* Increase the refcnt counter of the dest */
 552         atomic_inc(&dest->refcnt);
 553
 554         conn_flags = atomic_read(&dest->conn_flags);
 555         if (cp->protocol != IPPROTO_UDP)
 556                 conn_flags &= ~IP_VS_CONN_F_ONE_PACKET;
 557         flags = cp->flags;
 558         /* Bind with the destination and its corresponding transmitter */
 559         if (flags & IP_VS_CONN_F_SYNC) {
 560                 /* if the connection is not template and is created
 561                  * by sync, preserve the activity flag.
 562                  */
 563                 if (!(flags & IP_VS_CONN_F_TEMPLATE))
 564                         conn_flags &= ~IP_VS_CONN_F_INACTIVE;
 565                 /* connections inherit forwarding method from dest */
 566                 flags &= ~(IP_VS_CONN_F_FWD_MASK | IP_VS_CONN_F_NOOUTPUT);
 567         }
 568         flags |= conn_flags;
 569         cp->flags = flags;
 570         cp->dest = dest;
 571
 572         IP_VS_DBG_BUF(7, "Bind-dest %s c:%s:%d v:%s:%d "
 573                       "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
 574                       "dest->refcnt:%d\n",
 575                       ip_vs_proto_name(cp->protocol),
 576                       IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
 577                       IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
 578                       IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
 579                       ip_vs_fwd_tag(cp), cp->state,
 580                       cp->flags, atomic_read(&cp->refcnt),
 581                       atomic_read(&dest->refcnt));
 582
 583         /* Update the connection counters */
 584         if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
 585                 /* It is a normal connection, so modify the counters
 586                  * according to the flags, later the protocol can
 587                  * update them on state change
 588                  */
 589                 if (!(flags & IP_VS_CONN_F_INACTIVE))
 590                         atomic_inc(&dest->activeconns);
 591                 else
 592                         atomic_inc(&dest->inactconns);
 593         } else {
 594                 /* It is a persistent connection/template, so increase
 595                    the persistent connection counter */
 596                 atomic_inc(&dest->persistconns);
 597         }
 598
 599         if (dest->u_threshold != 0 &&
 600             ip_vs_dest_totalconns(dest) >= dest->u_threshold)
 601                 dest->flags |= IP_VS_DEST_F_OVERLOAD;
 602 }
 603
 604
 605 /*
 606  * Check if there is a destination for the connection, if so
 607  * bind the connection to the destination.
 608  */
 609 struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp)
 610 {
 611         struct ip_vs_dest *dest;
 612
 613         dest = ip_vs_find_dest(ip_vs_conn_net(cp), cp->af, &cp->daddr,
 614                                cp->dport, &cp->vaddr, cp->vport,
 615                                cp->protocol, cp->fwmark, cp->flags);
 616         if (dest) {
 617                 struct ip_vs_proto_data *pd;
 618
 619                 spin_lock(&cp->lock);
 620                 if (cp->dest) {
 621                         spin_unlock(&cp->lock);
 622                         return dest;
 623                 }
 624
 625                 /* Applications work depending on the forwarding method
 626                  * but better to reassign them always when binding dest */
 627                 if (cp->app)
 628                         ip_vs_unbind_app(cp);
 629
 630                 ip_vs_bind_dest(cp, dest);
 631                 spin_unlock(&cp->lock);
 632
 633                 /* Update its packet transmitter */
 634                 cp->packet_xmit = NULL;
 635 #ifdef CONFIG_IP_VS_IPV6
 636                 if (cp->af == AF_INET6)
 637                         ip_vs_bind_xmit_v6(cp);
 638                 else
 639 #endif
 640                         ip_vs_bind_xmit(cp);
 641
 642                 pd = ip_vs_proto_data_get(ip_vs_conn_net(cp), cp->protocol);
 643                 if (pd && atomic_read(&pd->appcnt))
 644                         ip_vs_bind_app(cp, pd->pp);
 645         }
 646         return dest;
 647 }
 648
 649
 650 /*
 651  *      Unbind a connection entry with its VS destination
 652  *      Called by the ip_vs_conn_expire function.
 653  */
 654 static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp)
 655 {
 656         struct ip_vs_dest *dest = cp->dest;
 657
 658         if (!dest)
 659                 return;
 660
 661         IP_VS_DBG_BUF(7, "Unbind-dest %s c:%s:%d v:%s:%d "
 662                       "d:%s:%d fwd:%c s:%u conn->flags:%X conn->refcnt:%d "
 663                       "dest->refcnt:%d\n",
 664                       ip_vs_proto_name(cp->protocol),
 665                       IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
 666                       IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
 667                       IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
 668                       ip_vs_fwd_tag(cp), cp->state,
 669                       cp->flags, atomic_read(&cp->refcnt),
 670                       atomic_read(&dest->refcnt));
 671
 672         /* Update the connection counters */
 673         if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
 674                 /* It is a normal connection, so decrease the inactconns
 675                    or activeconns counter */
 676                 if (cp->flags & IP_VS_CONN_F_INACTIVE) {
 677                         atomic_dec(&dest->inactconns);
 678                 } else {
 679                         atomic_dec(&dest->activeconns);
 680                 }
 681         } else {
 682                 /* It is a persistent connection/template, so decrease
 683                    the persistent connection counter */
 684                 atomic_dec(&dest->persistconns);
 685         }
 686
 687         if (dest->l_threshold != 0) {
 688                 if (ip_vs_dest_totalconns(dest) < dest->l_threshold)
 689                         dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
 690         } else if (dest->u_threshold != 0) {
 691                 if (ip_vs_dest_totalconns(dest) * 4 < dest->u_threshold * 3)
 692                         dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
 693         } else {
 694                 if (dest->flags & IP_VS_DEST_F_OVERLOAD)
 695                         dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
 696         }
 697
 698         /*
 699          * Simply decrease the refcnt of the dest, because the
 700          * dest will be either in service's destination list
 701          * or in the trash.
 702          */
 703         atomic_dec(&dest->refcnt);
 704 }
 705
 706 static int expire_quiescent_template(struct netns_ipvs *ipvs,
 707                                      struct ip_vs_dest *dest)
 708 {
 709 #ifdef CONFIG_SYSCTL
 710         return ipvs->sysctl_expire_quiescent_template &&
 711                 (atomic_read(&dest->weight) == 0);
 712 #else
 713         return 0;
 714 #endif
 715 }
 716
 717 /*
 718  *      Checking if the destination of a connection template is available.
 719  *      If available, return 1, otherwise invalidate this connection
 720  *      template and return 0.
 721  */
 722 int ip_vs_check_template(struct ip_vs_conn *ct)
 723 {
 724         struct ip_vs_dest *dest = ct->dest;
 725         struct netns_ipvs *ipvs = net_ipvs(ip_vs_conn_net(ct));
 726
 727         /*
 728          * Checking the dest server status.
 729          */
 730         if ((dest == NULL) ||
 731             !(dest->flags & IP_VS_DEST_F_AVAILABLE) ||
 732             expire_quiescent_template(ipvs, dest)) {
 733                 IP_VS_DBG_BUF(9, "check_template: dest not available for "
 734                               "protocol %s s:%s:%d v:%s:%d "
 735                               "-> d:%s:%d\n",
 736                               ip_vs_proto_name(ct->protocol),
 737                               IP_VS_DBG_ADDR(ct->af, &ct->caddr),
 738                               ntohs(ct->cport),
 739                               IP_VS_DBG_ADDR(ct->af, &ct->vaddr),
 740                               ntohs(ct->vport),
 741                               IP_VS_DBG_ADDR(ct->af, &ct->daddr),
 742                               ntohs(ct->dport));
 743
 744                 /*
 745                  * Invalidate the connection template
 746                  */
 747                 if (ct->vport != htons(0xffff)) {
 748                         if (ip_vs_conn_unhash(ct)) {
 749                                 ct->dport = htons(0xffff);
 750                                 ct->vport = htons(0xffff);
 751                                 ct->cport = 0;
 752                                 ip_vs_conn_hash(ct);
 753                         }
 754                 }
 755
 756                 /*
 757                  * Simply decrease the refcnt of the template,
 758                  * don't restart its timer.
 759                  */
 760                 atomic_dec(&ct->refcnt);
 761                 return 0;
 762         }
 763         return 1;
 764 }
 765
 766 static void ip_vs_conn_expire(unsigned long data)
 767 {
 768         struct ip_vs_conn *cp = (struct ip_vs_conn *)data;
 769         struct net *net = ip_vs_conn_net(cp);
 770         struct netns_ipvs *ipvs = net_ipvs(net);
 771
 772         cp->timeout = 60*HZ;
 773
 774         /*
 775          *      hey, I'm using it
 776          */
 777         atomic_inc(&cp->refcnt);
 778
 779         /*
 780          *      do I control anybody?
 781          */
 782         if (atomic_read(&cp->n_control))
 783                 goto expire_later;
 784
 785         /*
 786          *      unhash it if it is hashed in the conn table
 787          */
 788         if (!ip_vs_conn_unhash(cp) && !(cp->flags & IP_VS_CONN_F_ONE_PACKET))
 789                 goto expire_later;
 790
 791         /*
 792          *      refcnt==1 implies I'm the only one referrer
 793          */
 794         if (likely(atomic_read(&cp->refcnt) == 1)) {
 795                 /* delete the timer if it is activated by other users */
 796                 del_timer(&cp->timer);
 797
 798                 /* does anybody control me? */
 799                 if (cp->control)
 800                         ip_vs_control_del(cp);
 801
 802                 if (cp->flags & IP_VS_CONN_F_NFCT) {
 803                         ip_vs_conn_drop_conntrack(cp);
 804                         /* Do not access conntracks during subsys cleanup
 805                          * because nf_conntrack_find_get can not be used after
 806                          * conntrack cleanup for the net.
 807                          */
 808                         smp_rmb();
 809                         if (ipvs->enable)
 810                                 ip_vs_conn_drop_conntrack(cp);
 811                 }
 812
 813                 ip_vs_pe_put(cp->pe);
 814                 kfree(cp->pe_data);
 815                 if (unlikely(cp->app != NULL))
 816                         ip_vs_unbind_app(cp);
 817                 ip_vs_unbind_dest(cp);
 818                 if (cp->flags & IP_VS_CONN_F_NO_CPORT)
 819                         atomic_dec(&ip_vs_conn_no_cport_cnt);
 820                 atomic_dec(&ipvs->conn_count);
 821
 822                 kmem_cache_free(ip_vs_conn_cachep, cp);
 823                 return;
 824         }
 825
 826         /* hash it back to the table */
 827         ip_vs_conn_hash(cp);
 828
 829   expire_later:
 830         IP_VS_DBG(7, "delayed: conn->refcnt-1=%d conn->n_control=%d\n",
 831                   atomic_read(&cp->refcnt)-1,
 832                   atomic_read(&cp->n_control));
 833
 834         if (ipvs->sync_state & IP_VS_STATE_MASTER)
 835                 ip_vs_sync_conn(net, cp, sysctl_sync_threshold(ipvs));
 836
 837         ip_vs_conn_put(cp);
 838 }
 839
 840
 841 void ip_vs_conn_expire_now(struct ip_vs_conn *cp)
 842 {
 843         if (del_timer(&cp->timer))
 844                 mod_timer(&cp->timer, jiffies);
 845 }
 846
 847
 848 /*
 849  *      Create a new connection entry and hash it into the ip_vs_conn_tab
 850  */
 851 struct ip_vs_conn *
 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)
 855 {
 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,
 859                                                            p->protocol);
 860
 861         cp = kmem_cache_zalloc(ip_vs_conn_cachep, GFP_ATOMIC);
 862         if (cp == NULL) {
 863                 IP_VS_ERR_RL("%s(): no memory\n", __func__);
 864                 return NULL;
 865         }
 866
 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);
 870         cp->af             = p->af;
 871         cp->protocol       = p->protocol;
 872         ip_vs_addr_copy(p->af, &cp->caddr, p->caddr);
 873         cp->cport          = p->cport;
 874         ip_vs_addr_copy(p->af, &cp->vaddr, p->vaddr);
 875         cp->vport          = p->vport;
 876         /* proto should only be IPPROTO_IP if d_addr is a fwmark */
 877         ip_vs_addr_copy(p->protocol == IPPROTO_IP ? AF_UNSPEC : p->af,
 878                         &cp->daddr, daddr);
 879         cp->dport          = dport;
 880         cp->flags          = flags;
 881         cp->fwmark         = fwmark;
 882         if (flags & IP_VS_CONN_F_TEMPLATE && p->pe) {
 883                 ip_vs_pe_get(p->pe);
 884                 cp->pe = p->pe;
 885                 cp->pe_data = p->pe_data;
 886                 cp->pe_data_len = p->pe_data_len;
 887         }
 888         spin_lock_init(&cp->lock);
 889
 890         /*
 891          * Set the entry is referenced by the current thread before hashing
 892          * it in the table, so that other thread run ip_vs_random_dropentry
 893          * but cannot drop this entry.
 894          */
 895         atomic_set(&cp->refcnt, 1);
 896
 897         atomic_set(&cp->n_control, 0);
 898         atomic_set(&cp->in_pkts, 0);
 899
 900         atomic_inc(&ipvs->conn_count);
 901         if (flags & IP_VS_CONN_F_NO_CPORT)
 902                 atomic_inc(&ip_vs_conn_no_cport_cnt);
 903
 904         /* Bind the connection with a destination server */
 905         ip_vs_bind_dest(cp, dest);
 906
 907         /* Set its state and timeout */
 908         cp->state = 0;
 909         cp->timeout = 3*HZ;
 910         cp->sync_endtime = jiffies & ~3UL;
 911
 912         /* Bind its packet transmitter */
 913 #ifdef CONFIG_IP_VS_IPV6
 914         if (p->af == AF_INET6)
 915                 ip_vs_bind_xmit_v6(cp);
 916         else
 917 #endif
 918                 ip_vs_bind_xmit(cp);
 919
 920         if (unlikely(pd && atomic_read(&pd->appcnt)))
 921                 ip_vs_bind_app(cp, pd->pp);
 922
 923         /*
 924          * Allow conntrack to be preserved. By default, conntrack
 925          * is created and destroyed for every packet.
 926          * Sometimes keeping conntrack can be useful for
 927          * IP_VS_CONN_F_ONE_PACKET too.
 928          */
 929
 930         if (ip_vs_conntrack_enabled(ipvs))
 931                 cp->flags |= IP_VS_CONN_F_NFCT;
 932
 933         /* Hash it in the ip_vs_conn_tab finally */
 934         ip_vs_conn_hash(cp);
 935
 936         return cp;
 937 }
 938
 939 /*
 940  *      /proc/net/ip_vs_conn entries
 941  */
 942 #ifdef CONFIG_PROC_FS
 943 struct ip_vs_iter_state {
 944         struct seq_net_private  p;
 945         struct hlist_head       *l;
 946 };
 947
 948 static void *ip_vs_conn_array(struct seq_file *seq, loff_t pos)
 949 {
 950         int idx;
 951         struct ip_vs_conn *cp;
 952         struct ip_vs_iter_state *iter = seq->private;
 953
 954         for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
 955                 ct_read_lock_bh(idx);
 956                 hlist_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
 957                         if (pos-- == 0) {
 958                                 iter->l = &ip_vs_conn_tab[idx];
 959                                 return cp;
 960                         }
 961                 }
 962                 ct_read_unlock_bh(idx);
 963         }
 964
 965         return NULL;
 966 }
 967
 968 static void *ip_vs_conn_seq_start(struct seq_file *seq, loff_t *pos)
 969 {
 970         struct ip_vs_iter_state *iter = seq->private;
 971
 972         iter->l = NULL;
 973         return *pos ? ip_vs_conn_array(seq, *pos - 1) :SEQ_START_TOKEN;
 974 }
 975
 976 static void *ip_vs_conn_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 977 {
 978         struct ip_vs_conn *cp = v;
 979         struct ip_vs_iter_state *iter = seq->private;
 980         struct hlist_head *l = iter->l;
 981         int idx;
 982
 983         ++*pos;
 984         if (v == SEQ_START_TOKEN)
 985                 return ip_vs_conn_array(seq, 0);
 986
 987         /* more on same hash chain? */
 988         if (cp->c_list.next)
 989                 return hlist_entry(cp->c_list.next, struct ip_vs_conn, c_list);
 990
 991         idx = l - ip_vs_conn_tab;
 992         ct_read_unlock_bh(idx);
 993
 994         while (++idx < ip_vs_conn_tab_size) {
 995                 ct_read_lock_bh(idx);
 996                 hlist_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
 997                         iter->l = &ip_vs_conn_tab[idx];
 998                         return cp;
 999                 }
1000                 ct_read_unlock_bh(idx);
1001         }
1002         iter->l = NULL;
1003         return NULL;
1004 }
1005
1006 static void ip_vs_conn_seq_stop(struct seq_file *seq, void *v)
1007 {
1008         struct ip_vs_iter_state *iter = seq->private;
1009         struct hlist_head *l = iter->l;
1010
1011         if (l)
1012                 ct_read_unlock_bh(l - ip_vs_conn_tab);
1013 }
1014
1015 static int ip_vs_conn_seq_show(struct seq_file *seq, void *v)
1016 {
1017
1018         if (v == SEQ_START_TOKEN)
1019                 seq_puts(seq,
1020    "Pro FromIP   FPrt ToIP     TPrt DestIP   DPrt State       Expires PEName PEData\n");
1021         else {
1022                 const struct ip_vs_conn *cp = v;
1023                 struct net *net = seq_file_net(seq);
1024                 char pe_data[IP_VS_PENAME_MAXLEN + IP_VS_PEDATA_MAXLEN + 3];
1025                 size_t len = 0;
1026
1027                 if (!ip_vs_conn_net_eq(cp, net))
1028                         return 0;
1029                 if (cp->pe_data) {
1030                         pe_data[0] = ' ';
1031                         len = strlen(cp->pe->name);
1032                         memcpy(pe_data + 1, cp->pe->name, len);
1033                         pe_data[len + 1] = ' ';
1034                         len += 2;
1035                         len += cp->pe->show_pe_data(cp, pe_data + len);
1036                 }
1037                 pe_data[len] = '\0';
1038
1039 #ifdef CONFIG_IP_VS_IPV6
1040                 if (cp->af == AF_INET6)
1041                         seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X "
1042                                 "%pI6 %04X %-11s %7lu%s\n",
1043                                 ip_vs_proto_name(cp->protocol),
1044                                 &cp->caddr.in6, ntohs(cp->cport),
1045                                 &cp->vaddr.in6, ntohs(cp->vport),
1046                                 &cp->daddr.in6, ntohs(cp->dport),
1047                                 ip_vs_state_name(cp->protocol, cp->state),
1048                                 (cp->timer.expires-jiffies)/HZ, pe_data);
1049                 else
1050 #endif
1051                         seq_printf(seq,
1052                                 "%-3s %08X %04X %08X %04X"
1053                                 " %08X %04X %-11s %7lu%s\n",
1054                                 ip_vs_proto_name(cp->protocol),
1055                                 ntohl(cp->caddr.ip), ntohs(cp->cport),
1056                                 ntohl(cp->vaddr.ip), ntohs(cp->vport),
1057                                 ntohl(cp->daddr.ip), ntohs(cp->dport),
1058                                 ip_vs_state_name(cp->protocol, cp->state),
1059                                 (cp->timer.expires-jiffies)/HZ, pe_data);
1060         }
1061         return 0;
1062 }
1063
1064 static const struct seq_operations ip_vs_conn_seq_ops = {
1065         .start = ip_vs_conn_seq_start,
1066         .next  = ip_vs_conn_seq_next,
1067         .stop  = ip_vs_conn_seq_stop,
1068         .show  = ip_vs_conn_seq_show,
1069 };
1070
1071 static int ip_vs_conn_open(struct inode *inode, struct file *file)
1072 {
1073         return seq_open_net(inode, file, &ip_vs_conn_seq_ops,
1074                             sizeof(struct ip_vs_iter_state));
1075 }
1076
1077 static const struct file_operations ip_vs_conn_fops = {
1078         .owner   = THIS_MODULE,
1079         .open    = ip_vs_conn_open,
1080         .read    = seq_read,
1081         .llseek  = seq_lseek,
1082         .release = seq_release_net,
1083 };
1084
1085 static const char *ip_vs_origin_name(unsigned int flags)
1086 {
1087         if (flags & IP_VS_CONN_F_SYNC)
1088                 return "SYNC";
1089         else
1090                 return "LOCAL";
1091 }
1092
1093 static int ip_vs_conn_sync_seq_show(struct seq_file *seq, void *v)
1094 {
1095
1096         if (v == SEQ_START_TOKEN)
1097                 seq_puts(seq,
1098    "Pro FromIP   FPrt ToIP     TPrt DestIP   DPrt State       Origin Expires\n");
1099         else {
1100                 const struct ip_vs_conn *cp = v;
1101                 struct net *net = seq_file_net(seq);
1102
1103                 if (!ip_vs_conn_net_eq(cp, net))
1104                         return 0;
1105
1106 #ifdef CONFIG_IP_VS_IPV6
1107                 if (cp->af == AF_INET6)
1108                         seq_printf(seq, "%-3s %pI6 %04X %pI6 %04X %pI6 %04X %-11s %-6s %7lu\n",
1109                                 ip_vs_proto_name(cp->protocol),
1110                                 &cp->caddr.in6, ntohs(cp->cport),
1111                                 &cp->vaddr.in6, ntohs(cp->vport),
1112                                 &cp->daddr.in6, ntohs(cp->dport),
1113                                 ip_vs_state_name(cp->protocol, cp->state),
1114                                 ip_vs_origin_name(cp->flags),
1115                                 (cp->timer.expires-jiffies)/HZ);
1116                 else
1117 #endif
1118                         seq_printf(seq,
1119                                 "%-3s %08X %04X %08X %04X "
1120                                 "%08X %04X %-11s %-6s %7lu\n",
1121                                 ip_vs_proto_name(cp->protocol),
1122                                 ntohl(cp->caddr.ip), ntohs(cp->cport),
1123                                 ntohl(cp->vaddr.ip), ntohs(cp->vport),
1124                                 ntohl(cp->daddr.ip), ntohs(cp->dport),
1125                                 ip_vs_state_name(cp->protocol, cp->state),
1126                                 ip_vs_origin_name(cp->flags),
1127                                 (cp->timer.expires-jiffies)/HZ);
1128         }
1129         return 0;
1130 }
1131
1132 static const struct seq_operations ip_vs_conn_sync_seq_ops = {
1133         .start = ip_vs_conn_seq_start,
1134         .next  = ip_vs_conn_seq_next,
1135         .stop  = ip_vs_conn_seq_stop,
1136         .show  = ip_vs_conn_sync_seq_show,
1137 };
1138
1139 static int ip_vs_conn_sync_open(struct inode *inode, struct file *file)
1140 {
1141         return seq_open_net(inode, file, &ip_vs_conn_sync_seq_ops,
1142                             sizeof(struct ip_vs_iter_state));
1143 }
1144
1145 static const struct file_operations ip_vs_conn_sync_fops = {
1146         .owner   = THIS_MODULE,
1147         .open    = ip_vs_conn_sync_open,
1148         .read    = seq_read,
1149         .llseek  = seq_lseek,
1150         .release = seq_release_net,
1151 };
1152
1153 #endif
1154
1155
1156 /*
1157  *      Randomly drop connection entries before running out of memory
1158  */
1159 static inline int todrop_entry(struct ip_vs_conn *cp)
1160 {
1161         /*
1162          * The drop rate array needs tuning for real environments.
1163          * Called from timer bh only => no locking
1164          */
1165         static const char todrop_rate[9] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
1166         static char todrop_counter[9] = {0};
1167         int i;
1168
1169         /* if the conn entry hasn't lasted for 60 seconds, don't drop it.
1170            This will leave enough time for normal connection to get
1171            through. */
1172         if (time_before(cp->timeout + jiffies, cp->timer.expires + 60*HZ))
1173                 return 0;
1174
1175         /* Don't drop the entry if its number of incoming packets is not
1176            located in [0, 8] */
1177         i = atomic_read(&cp->in_pkts);
1178         if (i > 8 || i < 0) return 0;
1179
1180         if (!todrop_rate[i]) return 0;
1181         if (--todrop_counter[i] > 0) return 0;
1182
1183         todrop_counter[i] = todrop_rate[i];
1184         return 1;
1185 }
1186
1187 /* Called from keventd and must protect itself from softirqs */
1188 void ip_vs_random_dropentry(struct net *net)
1189 {
1190         int idx;
1191         struct ip_vs_conn *cp;
1192
1193         /*
1194          * Randomly scan 1/32 of the whole table every second
1195          */
1196         for (idx = 0; idx < (ip_vs_conn_tab_size>>5); idx++) {
1197                 unsigned int hash = net_random() & ip_vs_conn_tab_mask;
1198
1199                 /*
1200                  *  Lock is actually needed in this loop.
1201                  */
1202                 ct_write_lock_bh(hash);
1203
1204                 hlist_for_each_entry(cp, &ip_vs_conn_tab[hash], c_list) {
1205                         if (cp->flags & IP_VS_CONN_F_TEMPLATE)
1206                                 /* connection template */
1207                                 continue;
1208                         if (!ip_vs_conn_net_eq(cp, net))
1209                                 continue;
1210                         if (cp->protocol == IPPROTO_TCP) {
1211                                 switch(cp->state) {
1212                                 case IP_VS_TCP_S_SYN_RECV:
1213                                 case IP_VS_TCP_S_SYNACK:
1214                                         break;
1215
1216                                 case IP_VS_TCP_S_ESTABLISHED:
1217                                         if (todrop_entry(cp))
1218                                                 break;
1219                                         continue;
1220
1221                                 default:
1222                                         continue;
1223                                 }
1224                         } else {
1225                                 if (!todrop_entry(cp))
1226                                         continue;
1227                         }
1228
1229                         IP_VS_DBG(4, "del connection\n");
1230                         ip_vs_conn_expire_now(cp);
1231                         if (cp->control) {
1232                                 IP_VS_DBG(4, "del conn template\n");
1233                                 ip_vs_conn_expire_now(cp->control);
1234                         }
1235                 }
1236                 ct_write_unlock_bh(hash);
1237         }
1238 }
1239
1240
1241 /*
1242  *      Flush all the connection entries in the ip_vs_conn_tab
1243  */
1244 static void ip_vs_conn_flush(struct net *net)
1245 {
1246         int idx;
1247         struct ip_vs_conn *cp;
1248         struct netns_ipvs *ipvs = net_ipvs(net);
1249
1250 flush_again:
1251         for (idx = 0; idx < ip_vs_conn_tab_size; idx++) {
1252                 /*
1253                  *  Lock is actually needed in this loop.
1254                  */
1255                 ct_write_lock_bh(idx);
1256
1257                 hlist_for_each_entry(cp, &ip_vs_conn_tab[idx], c_list) {
1258                         if (!ip_vs_conn_net_eq(cp, net))
1259                                 continue;
1260                         IP_VS_DBG(4, "del connection\n");
1261                         ip_vs_conn_expire_now(cp);
1262                         if (cp->control) {
1263                                 IP_VS_DBG(4, "del conn template\n");
1264                                 ip_vs_conn_expire_now(cp->control);
1265                         }
1266                 }
1267                 ct_write_unlock_bh(idx);
1268         }
1269
1270         /* the counter may be not NULL, because maybe some conn entries
1271            are run by slow timer handler or unhashed but still referred */
1272         if (atomic_read(&ipvs->conn_count) != 0) {
1273                 schedule();
1274                 goto flush_again;
1275         }
1276 }
1277 /*
1278  * per netns init and exit
1279  */
1280 int __net_init ip_vs_conn_net_init(struct net *net)
1281 {
1282         struct netns_ipvs *ipvs = net_ipvs(net);
1283
1284         atomic_set(&ipvs->conn_count, 0);
1285
1286         proc_create("ip_vs_conn", 0, net->proc_net, &ip_vs_conn_fops);
1287         proc_create("ip_vs_conn_sync", 0, net->proc_net, &ip_vs_conn_sync_fops);
1288         return 0;
1289 }
1290
1291 void __net_exit ip_vs_conn_net_cleanup(struct net *net)
1292 {
1293         /* flush all the connection entries first */
1294         ip_vs_conn_flush(net);
1295         remove_proc_entry("ip_vs_conn", net->proc_net);
1296         remove_proc_entry("ip_vs_conn_sync", net->proc_net);
1297 }
1298
1299 int __init ip_vs_conn_init(void)
1300 {
1301         int idx;
1302
1303         /* Compute size and mask */
1304         ip_vs_conn_tab_size = 1 << ip_vs_conn_tab_bits;
1305         ip_vs_conn_tab_mask = ip_vs_conn_tab_size - 1;
1306
1307         /*
1308          * Allocate the connection hash table and initialize its list heads
1309          */
1310         ip_vs_conn_tab = vmalloc(ip_vs_conn_tab_size * sizeof(*ip_vs_conn_tab));
1311         if (!ip_vs_conn_tab)
1312                 return -ENOMEM;
1313
1314         /* Allocate ip_vs_conn slab cache */
1315         ip_vs_conn_cachep = kmem_cache_create("ip_vs_conn",
1316                                               sizeof(struct ip_vs_conn), 0,
1317                                               SLAB_HWCACHE_ALIGN, NULL);
1318         if (!ip_vs_conn_cachep) {
1319                 vfree(ip_vs_conn_tab);
1320                 return -ENOMEM;
1321         }
1322
1323         pr_info("Connection hash table configured "
1324                 "(size=%d, memory=%ldKbytes)\n",
1325                 ip_vs_conn_tab_size,
1326                 (long)(ip_vs_conn_tab_size*sizeof(struct list_head))/1024);
1327         IP_VS_DBG(0, "Each connection entry needs %Zd bytes at least\n",
1328                   sizeof(struct ip_vs_conn));
1329
1330         for (idx = 0; idx < ip_vs_conn_tab_size; idx++)
1331                 INIT_HLIST_HEAD(&ip_vs_conn_tab[idx]);
1332
1333         for (idx = 0; idx < CT_LOCKARRAY_SIZE; idx++)  {
1334                 rwlock_init(&__ip_vs_conntbl_lock_array[idx].l);
1335         }
1336
1337         /* calculate the random value for connection hash */
1338         get_random_bytes(&ip_vs_conn_rnd, sizeof(ip_vs_conn_rnd));
1339
1340         return 0;
1341 }
1342
1343 void ip_vs_conn_cleanup(void)
1344 {
1345         /* Release the empty cache */
1346         kmem_cache_destroy(ip_vs_conn_cachep);
1347         vfree(ip_vs_conn_tab);
1348 }