net/netfilter/ipvs/ip_vs_sync.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  * Version 1,   is capable of handling both version 0 and 1 messages.
   9  *              Version 0 is the plain old format.
  10  *              Note Version 0 receivers will just drop Ver 1 messages.
  11  *              Version 1 is capable of handle IPv6, Persistence data,
  12  *              time-outs, and firewall marks.
  13  *              In ver.1 "ip_vs_sync_conn_options" will be sent in netw. order.
  14  *              Ver. 0 can be turned on by sysctl -w net.ipv4.vs.sync_version=0
  15  *
  16  * Definitions  Message: is a complete datagram
  17  *              Sync_conn: is a part of a Message
  18  *              Param Data is an option to a Sync_conn.
  19  *
  20  * Authors:     Wensong Zhang <wensong@linuxvirtualserver.org>
  21  *
  22  * ip_vs_sync:  sync connection info from master load balancer to backups
  23  *              through multicast
  24  *
  25  * Changes:
  26  *      Alexandre Cassen        :       Added master & backup support at a time.
  27  *      Alexandre Cassen        :       Added SyncID support for incoming sync
  28  *                                      messages filtering.
  29  *      Justin Ossevoort        :       Fix endian problem on sync message size.
  30  *      Hans Schillstrom        :       Added Version 1: i.e. IPv6,
  31  *                                      Persistence support, fwmark and time-out.
  32  */
  33
  34 #define KMSG_COMPONENT "IPVS"
  35 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  36
  37 #include <linux/module.h>
  38 #include <linux/slab.h>
  39 #include <linux/inetdevice.h>
  40 #include <linux/net.h>
  41 #include <linux/completion.h>
  42 #include <linux/delay.h>
  43 #include <linux/skbuff.h>
  44 #include <linux/in.h>
  45 #include <linux/igmp.h>                 /* for ip_mc_join_group */
  46 #include <linux/udp.h>
  47 #include <linux/err.h>
  48 #include <linux/kthread.h>
  49 #include <linux/wait.h>
  50 #include <linux/kernel.h>
  51
  52 #include <asm/unaligned.h>              /* Used for ntoh_seq and hton_seq */
  53
  54 #include <net/ip.h>
  55 #include <net/sock.h>
  56
  57 #include <net/ip_vs.h>
  58
  59 #define IP_VS_SYNC_GROUP 0xe0000051    /* multicast addr - 224.0.0.81 */
  60 #define IP_VS_SYNC_PORT  8848          /* multicast port */
  61
  62 #define SYNC_PROTO_VER  1               /* Protocol version in header */
  63
  64 static struct lock_class_key __ipvs_sync_key;
  65 /*
  66  *      IPVS sync connection entry
  67  *      Version 0, i.e. original version.
  68  */
  69 struct ip_vs_sync_conn_v0 {
  70         __u8                    reserved;
  71
  72         /* Protocol, addresses and port numbers */
  73         __u8                    protocol;       /* Which protocol (TCP/UDP) */
  74         __be16                  cport;
  75         __be16                  vport;
  76         __be16                  dport;
  77         __be32                  caddr;          /* client address */
  78         __be32                  vaddr;          /* virtual address */
  79         __be32                  daddr;          /* destination address */
  80
  81         /* Flags and state transition */
  82         __be16                  flags;          /* status flags */
  83         __be16                  state;          /* state info */
  84
  85         /* The sequence options start here */
  86 };
  87
  88 struct ip_vs_sync_conn_options {
  89         struct ip_vs_seq        in_seq;         /* incoming seq. struct */
  90         struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
  91 };
  92
  93 /*
  94      Sync Connection format (sync_conn)
  95
  96        0                   1                   2                   3
  97        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  98       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  99       |    Type       |    Protocol   | Ver.  |        Size           |
 100       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 101       |                             Flags                             |
 102       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 103       |            State              |         cport                 |
 104       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 105       |            vport              |         dport                 |
 106       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 107       |                             fwmark                            |
 108       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 109       |                             timeout  (in sec.)                |
 110       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 111       |                              ...                              |
 112       |                        IP-Addresses  (v4 or v6)               |
 113       |                              ...                              |
 114       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 115   Optional Parameters.
 116       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 117       | Param. Type    | Param. Length |   Param. data                |
 118       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               |
 119       |                              ...                              |
 120       |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 121       |                               | Param Type    | Param. Length |
 122       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 123       |                           Param  data                         |
 124       |         Last Param data should be padded for 32 bit alignment |
 125       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 126 */
 127
 128 /*
 129  *  Type 0, IPv4 sync connection format
 130  */
 131 struct ip_vs_sync_v4 {
 132         __u8                    type;
 133         __u8                    protocol;       /* Which protocol (TCP/UDP) */
 134         __be16                  ver_size;       /* Version msb 4 bits */
 135         /* Flags and state transition */
 136         __be32                  flags;          /* status flags */
 137         __be16                  state;          /* state info   */
 138         /* Protocol, addresses and port numbers */
 139         __be16                  cport;
 140         __be16                  vport;
 141         __be16                  dport;
 142         __be32                  fwmark;         /* Firewall mark from skb */
 143         __be32                  timeout;        /* cp timeout */
 144         __be32                  caddr;          /* client address */
 145         __be32                  vaddr;          /* virtual address */
 146         __be32                  daddr;          /* destination address */
 147         /* The sequence options start here */
 148         /* PE data padded to 32bit alignment after seq. options */
 149 };
 150 /*
 151  * Type 2 messages IPv6
 152  */
 153 struct ip_vs_sync_v6 {
 154         __u8                    type;
 155         __u8                    protocol;       /* Which protocol (TCP/UDP) */
 156         __be16                  ver_size;       /* Version msb 4 bits */
 157         /* Flags and state transition */
 158         __be32                  flags;          /* status flags */
 159         __be16                  state;          /* state info   */
 160         /* Protocol, addresses and port numbers */
 161         __be16                  cport;
 162         __be16                  vport;
 163         __be16                  dport;
 164         __be32                  fwmark;         /* Firewall mark from skb */
 165         __be32                  timeout;        /* cp timeout */
 166         struct in6_addr         caddr;          /* client address */
 167         struct in6_addr         vaddr;          /* virtual address */
 168         struct in6_addr         daddr;          /* destination address */
 169         /* The sequence options start here */
 170         /* PE data padded to 32bit alignment after seq. options */
 171 };
 172
 173 union ip_vs_sync_conn {
 174         struct ip_vs_sync_v4    v4;
 175         struct ip_vs_sync_v6    v6;
 176 };
 177
 178 /* Bits in Type field in above */
 179 #define STYPE_INET6             0
 180 #define STYPE_F_INET6           (1 << STYPE_INET6)
 181
 182 #define SVER_SHIFT              12              /* Shift to get version */
 183 #define SVER_MASK               0x0fff          /* Mask to strip version */
 184
 185 #define IPVS_OPT_SEQ_DATA       1
 186 #define IPVS_OPT_PE_DATA        2
 187 #define IPVS_OPT_PE_NAME        3
 188 #define IPVS_OPT_PARAM          7
 189
 190 #define IPVS_OPT_F_SEQ_DATA     (1 << (IPVS_OPT_SEQ_DATA-1))
 191 #define IPVS_OPT_F_PE_DATA      (1 << (IPVS_OPT_PE_DATA-1))
 192 #define IPVS_OPT_F_PE_NAME      (1 << (IPVS_OPT_PE_NAME-1))
 193 #define IPVS_OPT_F_PARAM        (1 << (IPVS_OPT_PARAM-1))
 194
 195 struct ip_vs_sync_thread_data {
 196         struct net *net;
 197         struct socket *sock;
 198         char *buf;
 199         int id;
 200 };
 201
 202 /* Version 0 definition of packet sizes */
 203 #define SIMPLE_CONN_SIZE  (sizeof(struct ip_vs_sync_conn_v0))
 204 #define FULL_CONN_SIZE  \
 205 (sizeof(struct ip_vs_sync_conn_v0) + sizeof(struct ip_vs_sync_conn_options))
 206
 207
 208 /*
 209   The master mulitcasts messages (Datagrams) to the backup load balancers
 210   in the following format.
 211
 212  Version 1:
 213   Note, first byte should be Zero, so ver 0 receivers will drop the packet.
 214
 215        0                   1                   2                   3
 216        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 217       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 218       |      0        |    SyncID     |            Size               |
 219       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 220       |  Count Conns  |    Version    |    Reserved, set to Zero      |
 221       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 222       |                                                               |
 223       |                    IPVS Sync Connection (1)                   |
 224       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 225       |                            .                                  |
 226       ~                            .                                  ~
 227       |                            .                                  |
 228       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 229       |                                                               |
 230       |                    IPVS Sync Connection (n)                   |
 231       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 232
 233  Version 0 Header
 234        0                   1                   2                   3
 235        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 236       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 237       |  Count Conns  |    SyncID     |            Size               |
 238       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 239       |                    IPVS Sync Connection (1)                   |
 240 */
 241
 242 #define SYNC_MESG_HEADER_LEN    4
 243 #define MAX_CONNS_PER_SYNCBUFF  255 /* nr_conns in ip_vs_sync_mesg is 8 bit */
 244
 245 /* Version 0 header */
 246 struct ip_vs_sync_mesg_v0 {
 247         __u8                    nr_conns;
 248         __u8                    syncid;
 249         __be16                  size;
 250
 251         /* ip_vs_sync_conn entries start here */
 252 };
 253
 254 /* Version 1 header */
 255 struct ip_vs_sync_mesg {
 256         __u8                    reserved;       /* must be zero */
 257         __u8                    syncid;
 258         __be16                  size;
 259         __u8                    nr_conns;
 260         __s8                    version;        /* SYNC_PROTO_VER  */
 261         __u16                   spare;
 262         /* ip_vs_sync_conn entries start here */
 263 };
 264
 265 struct ip_vs_sync_buff {
 266         struct list_head        list;
 267         unsigned long           firstuse;
 268
 269         /* pointers for the message data */
 270         struct ip_vs_sync_mesg  *mesg;
 271         unsigned char           *head;
 272         unsigned char           *end;
 273 };
 274
 275 /*
 276  * Copy of struct ip_vs_seq
 277  * From unaligned network order to aligned host order
 278  */
 279 static void ntoh_seq(struct ip_vs_seq *no, struct ip_vs_seq *ho)
 280 {
 281         ho->init_seq       = get_unaligned_be32(&no->init_seq);
 282         ho->delta          = get_unaligned_be32(&no->delta);
 283         ho->previous_delta = get_unaligned_be32(&no->previous_delta);
 284 }
 285
 286 /*
 287  * Copy of struct ip_vs_seq
 288  * From Aligned host order to unaligned network order
 289  */
 290 static void hton_seq(struct ip_vs_seq *ho, struct ip_vs_seq *no)
 291 {
 292         put_unaligned_be32(ho->init_seq, &no->init_seq);
 293         put_unaligned_be32(ho->delta, &no->delta);
 294         put_unaligned_be32(ho->previous_delta, &no->previous_delta);
 295 }
 296
 297 static inline struct ip_vs_sync_buff *
 298 sb_dequeue(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
 299 {
 300         struct ip_vs_sync_buff *sb;
 301
 302         spin_lock_bh(&ipvs->sync_lock);
 303         if (list_empty(&ms->sync_queue)) {
 304                 sb = NULL;
 305                 __set_current_state(TASK_INTERRUPTIBLE);
 306         } else {
 307                 sb = list_entry(ms->sync_queue.next, struct ip_vs_sync_buff,
 308                                 list);
 309                 list_del(&sb->list);
 310                 ms->sync_queue_len--;
 311                 if (!ms->sync_queue_len)
 312                         ms->sync_queue_delay = 0;
 313         }
 314         spin_unlock_bh(&ipvs->sync_lock);
 315
 316         return sb;
 317 }
 318
 319 /*
 320  * Create a new sync buffer for Version 1 proto.
 321  */
 322 static inline struct ip_vs_sync_buff *
 323 ip_vs_sync_buff_create(struct netns_ipvs *ipvs)
 324 {
 325         struct ip_vs_sync_buff *sb;
 326
 327         if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
 328                 return NULL;
 329
 330         sb->mesg = kmalloc(ipvs->send_mesg_maxlen, GFP_ATOMIC);
 331         if (!sb->mesg) {
 332                 kfree(sb);
 333                 return NULL;
 334         }
 335         sb->mesg->reserved = 0;  /* old nr_conns i.e. must be zero now */
 336         sb->mesg->version = SYNC_PROTO_VER;
 337         sb->mesg->syncid = ipvs->master_syncid;
 338         sb->mesg->size = htons(sizeof(struct ip_vs_sync_mesg));
 339         sb->mesg->nr_conns = 0;
 340         sb->mesg->spare = 0;
 341         sb->head = (unsigned char *)sb->mesg + sizeof(struct ip_vs_sync_mesg);
 342         sb->end = (unsigned char *)sb->mesg + ipvs->send_mesg_maxlen;
 343
 344         sb->firstuse = jiffies;
 345         return sb;
 346 }
 347
 348 static inline void ip_vs_sync_buff_release(struct ip_vs_sync_buff *sb)
 349 {
 350         kfree(sb->mesg);
 351         kfree(sb);
 352 }
 353
 354 static inline void sb_queue_tail(struct netns_ipvs *ipvs,
 355                                  struct ipvs_master_sync_state *ms)
 356 {
 357         struct ip_vs_sync_buff *sb = ms->sync_buff;
 358
 359         spin_lock(&ipvs->sync_lock);
 360         if (ipvs->sync_state & IP_VS_STATE_MASTER &&
 361             ms->sync_queue_len < sysctl_sync_qlen_max(ipvs)) {
 362                 if (!ms->sync_queue_len)
 363                         schedule_delayed_work(&ms->master_wakeup_work,
 364                                               max(IPVS_SYNC_SEND_DELAY, 1));
 365                 ms->sync_queue_len++;
 366                 list_add_tail(&sb->list, &ms->sync_queue);
 367                 if ((++ms->sync_queue_delay) == IPVS_SYNC_WAKEUP_RATE)
 368                         wake_up_process(ms->master_thread);
 369         } else
 370                 ip_vs_sync_buff_release(sb);
 371         spin_unlock(&ipvs->sync_lock);
 372 }
 373
 374 /*
 375  *      Get the current sync buffer if it has been created for more
 376  *      than the specified time or the specified time is zero.
 377  */
 378 static inline struct ip_vs_sync_buff *
 379 get_curr_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms,
 380                    unsigned long time)
 381 {
 382         struct ip_vs_sync_buff *sb;
 383
 384         spin_lock_bh(&ipvs->sync_buff_lock);
 385         sb = ms->sync_buff;
 386         if (sb && time_after_eq(jiffies - sb->firstuse, time)) {
 387                 ms->sync_buff = NULL;
 388                 __set_current_state(TASK_RUNNING);
 389         } else
 390                 sb = NULL;
 391         spin_unlock_bh(&ipvs->sync_buff_lock);
 392         return sb;
 393 }
 394
 395 static inline int
 396 select_master_thread_id(struct netns_ipvs *ipvs, struct ip_vs_conn *cp)
 397 {
 398         return ((long) cp >> (1 + ilog2(sizeof(*cp)))) & ipvs->threads_mask;
 399 }
 400
 401 /*
 402  * Create a new sync buffer for Version 0 proto.
 403  */
 404 static inline struct ip_vs_sync_buff *
 405 ip_vs_sync_buff_create_v0(struct netns_ipvs *ipvs)
 406 {
 407         struct ip_vs_sync_buff *sb;
 408         struct ip_vs_sync_mesg_v0 *mesg;
 409
 410         if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
 411                 return NULL;
 412
 413         sb->mesg = kmalloc(ipvs->send_mesg_maxlen, GFP_ATOMIC);
 414         if (!sb->mesg) {
 415                 kfree(sb);
 416                 return NULL;
 417         }
 418         mesg = (struct ip_vs_sync_mesg_v0 *)sb->mesg;
 419         mesg->nr_conns = 0;
 420         mesg->syncid = ipvs->master_syncid;
 421         mesg->size = htons(sizeof(struct ip_vs_sync_mesg_v0));
 422         sb->head = (unsigned char *)mesg + sizeof(struct ip_vs_sync_mesg_v0);
 423         sb->end = (unsigned char *)mesg + ipvs->send_mesg_maxlen;
 424         sb->firstuse = jiffies;
 425         return sb;
 426 }
 427
 428 /* Check if connection is controlled by persistence */
 429 static inline bool in_persistence(struct ip_vs_conn *cp)
 430 {
 431         for (cp = cp->control; cp; cp = cp->control) {
 432                 if (cp->flags & IP_VS_CONN_F_TEMPLATE)
 433                         return true;
 434         }
 435         return false;
 436 }
 437
 438 /* Check if conn should be synced.
 439  * pkts: conn packets, use sysctl_sync_threshold to avoid packet check
 440  * - (1) sync_refresh_period: reduce sync rate. Additionally, retry
 441  *      sync_retries times with period of sync_refresh_period/8
 442  * - (2) if both sync_refresh_period and sync_period are 0 send sync only
 443  *      for state changes or only once when pkts matches sync_threshold
 444  * - (3) templates: rate can be reduced only with sync_refresh_period or
 445  *      with (2)
 446  */
 447 static int ip_vs_sync_conn_needed(struct netns_ipvs *ipvs,
 448                                   struct ip_vs_conn *cp, int pkts)
 449 {
 450         unsigned long orig = ACCESS_ONCE(cp->sync_endtime);
 451         unsigned long now = jiffies;
 452         unsigned long n = (now + cp->timeout) & ~3UL;
 453         unsigned int sync_refresh_period;
 454         int sync_period;
 455         int force;
 456
 457         /* Check if we sync in current state */
 458         if (unlikely(cp->flags & IP_VS_CONN_F_TEMPLATE))
 459                 force = 0;
 460         else if (unlikely(sysctl_sync_persist_mode(ipvs) && in_persistence(cp)))
 461                 return 0;
 462         else if (likely(cp->protocol == IPPROTO_TCP)) {
 463                 if (!((1 << cp->state) &
 464                       ((1 << IP_VS_TCP_S_ESTABLISHED) |
 465                        (1 << IP_VS_TCP_S_FIN_WAIT) |
 466                        (1 << IP_VS_TCP_S_CLOSE) |
 467                        (1 << IP_VS_TCP_S_CLOSE_WAIT) |
 468                        (1 << IP_VS_TCP_S_TIME_WAIT))))
 469                         return 0;
 470                 force = cp->state != cp->old_state;
 471                 if (force && cp->state != IP_VS_TCP_S_ESTABLISHED)
 472                         goto set;
 473         } else if (unlikely(cp->protocol == IPPROTO_SCTP)) {
 474                 if (!((1 << cp->state) &
 475                       ((1 << IP_VS_SCTP_S_ESTABLISHED) |
 476                        (1 << IP_VS_SCTP_S_SHUTDOWN_SENT) |
 477                        (1 << IP_VS_SCTP_S_SHUTDOWN_RECEIVED) |
 478                        (1 << IP_VS_SCTP_S_SHUTDOWN_ACK_SENT) |
 479                        (1 << IP_VS_SCTP_S_CLOSED))))
 480                         return 0;
 481                 force = cp->state != cp->old_state;
 482                 if (force && cp->state != IP_VS_SCTP_S_ESTABLISHED)
 483                         goto set;
 484         } else {
 485                 /* UDP or another protocol with single state */
 486                 force = 0;
 487         }
 488
 489         sync_refresh_period = sysctl_sync_refresh_period(ipvs);
 490         if (sync_refresh_period > 0) {
 491                 long diff = n - orig;
 492                 long min_diff = max(cp->timeout >> 1, 10UL * HZ);
 493
 494                 /* Avoid sync if difference is below sync_refresh_period
 495                  * and below the half timeout.
 496                  */
 497                 if (abs(diff) < min_t(long, sync_refresh_period, min_diff)) {
 498                         int retries = orig & 3;
 499
 500                         if (retries >= sysctl_sync_retries(ipvs))
 501                                 return 0;
 502                         if (time_before(now, orig - cp->timeout +
 503                                         (sync_refresh_period >> 3)))
 504                                 return 0;
 505                         n |= retries + 1;
 506                 }
 507         }
 508         sync_period = sysctl_sync_period(ipvs);
 509         if (sync_period > 0) {
 510                 if (!(cp->flags & IP_VS_CONN_F_TEMPLATE) &&
 511                     pkts % sync_period != sysctl_sync_threshold(ipvs))
 512                         return 0;
 513         } else if (sync_refresh_period <= 0 &&
 514                    pkts != sysctl_sync_threshold(ipvs))
 515                 return 0;
 516
 517 set:
 518         cp->old_state = cp->state;
 519         n = cmpxchg(&cp->sync_endtime, orig, n);
 520         return n == orig || force;
 521 }
 522
 523 /*
 524  *      Version 0 , could be switched in by sys_ctl.
 525  *      Add an ip_vs_conn information into the current sync_buff.
 526  */
 527 static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp,
 528                                int pkts)
 529 {
 530         struct netns_ipvs *ipvs = net_ipvs(net);
 531         struct ip_vs_sync_mesg_v0 *m;
 532         struct ip_vs_sync_conn_v0 *s;
 533         struct ip_vs_sync_buff *buff;
 534         struct ipvs_master_sync_state *ms;
 535         int id;
 536         int len;
 537
 538         if (unlikely(cp->af != AF_INET))
 539                 return;
 540         /* Do not sync ONE PACKET */
 541         if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
 542                 return;
 543
 544         if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
 545                 return;
 546
 547         spin_lock_bh(&ipvs->sync_buff_lock);
 548         if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
 549                 spin_unlock_bh(&ipvs->sync_buff_lock);
 550                 return;
 551         }
 552
 553         id = select_master_thread_id(ipvs, cp);
 554         ms = &ipvs->ms[id];
 555         buff = ms->sync_buff;
 556         if (buff) {
 557                 m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
 558                 /* Send buffer if it is for v1 */
 559                 if (!m->nr_conns) {
 560                         sb_queue_tail(ipvs, ms);
 561                         ms->sync_buff = NULL;
 562                         buff = NULL;
 563                 }
 564         }
 565         if (!buff) {
 566                 buff = ip_vs_sync_buff_create_v0(ipvs);
 567                 if (!buff) {
 568                         spin_unlock_bh(&ipvs->sync_buff_lock);
 569                         pr_err("ip_vs_sync_buff_create failed.\n");
 570                         return;
 571                 }
 572                 ms->sync_buff = buff;
 573         }
 574
 575         len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE :
 576                 SIMPLE_CONN_SIZE;
 577         m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
 578         s = (struct ip_vs_sync_conn_v0 *) buff->head;
 579
 580         /* copy members */
 581         s->reserved = 0;
 582         s->protocol = cp->protocol;
 583         s->cport = cp->cport;
 584         s->vport = cp->vport;
 585         s->dport = cp->dport;
 586         s->caddr = cp->caddr.ip;
 587         s->vaddr = cp->vaddr.ip;
 588         s->daddr = cp->daddr.ip;
 589         s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED);
 590         s->state = htons(cp->state);
 591         if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
 592                 struct ip_vs_sync_conn_options *opt =
 593                         (struct ip_vs_sync_conn_options *)&s[1];
 594                 memcpy(opt, &cp->in_seq, sizeof(*opt));
 595         }
 596
 597         m->nr_conns++;
 598         m->size = htons(ntohs(m->size) + len);
 599         buff->head += len;
 600
 601         /* check if there is a space for next one */
 602         if (buff->head + FULL_CONN_SIZE > buff->end) {
 603                 sb_queue_tail(ipvs, ms);
 604                 ms->sync_buff = NULL;
 605         }
 606         spin_unlock_bh(&ipvs->sync_buff_lock);
 607
 608         /* synchronize its controller if it has */
 609         cp = cp->control;
 610         if (cp) {
 611                 if (cp->flags & IP_VS_CONN_F_TEMPLATE)
 612                         pkts = atomic_add_return(1, &cp->in_pkts);
 613                 else
 614                         pkts = sysctl_sync_threshold(ipvs);
 615                 ip_vs_sync_conn(net, cp->control, pkts);
 616         }
 617 }
 618
 619 /*
 620  *      Add an ip_vs_conn information into the current sync_buff.
 621  *      Called by ip_vs_in.
 622  *      Sending Version 1 messages
 623  */
 624 void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp, int pkts)
 625 {
 626         struct netns_ipvs *ipvs = net_ipvs(net);
 627         struct ip_vs_sync_mesg *m;
 628         union ip_vs_sync_conn *s;
 629         struct ip_vs_sync_buff *buff;
 630         struct ipvs_master_sync_state *ms;
 631         int id;
 632         __u8 *p;
 633         unsigned int len, pe_name_len, pad;
 634
 635         /* Handle old version of the protocol */
 636         if (sysctl_sync_ver(ipvs) == 0) {
 637                 ip_vs_sync_conn_v0(net, cp, pkts);
 638                 return;
 639         }
 640         /* Do not sync ONE PACKET */
 641         if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
 642                 goto control;
 643 sloop:
 644         if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
 645                 goto control;
 646
 647         /* Sanity checks */
 648         pe_name_len = 0;
 649         if (cp->pe_data_len) {
 650                 if (!cp->pe_data || !cp->dest) {
 651                         IP_VS_ERR_RL("SYNC, connection pe_data invalid\n");
 652                         return;
 653                 }
 654                 pe_name_len = strnlen(cp->pe->name, IP_VS_PENAME_MAXLEN);
 655         }
 656
 657         spin_lock_bh(&ipvs->sync_buff_lock);
 658         if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
 659                 spin_unlock_bh(&ipvs->sync_buff_lock);
 660                 return;
 661         }
 662
 663         id = select_master_thread_id(ipvs, cp);
 664         ms = &ipvs->ms[id];
 665
 666 #ifdef CONFIG_IP_VS_IPV6
 667         if (cp->af == AF_INET6)
 668                 len = sizeof(struct ip_vs_sync_v6);
 669         else
 670 #endif
 671                 len = sizeof(struct ip_vs_sync_v4);
 672
 673         if (cp->flags & IP_VS_CONN_F_SEQ_MASK)
 674                 len += sizeof(struct ip_vs_sync_conn_options) + 2;
 675
 676         if (cp->pe_data_len)
 677                 len += cp->pe_data_len + 2;     /* + Param hdr field */
 678         if (pe_name_len)
 679                 len += pe_name_len + 2;
 680
 681         /* check if there is a space for this one  */
 682         pad = 0;
 683         buff = ms->sync_buff;
 684         if (buff) {
 685                 m = buff->mesg;
 686                 pad = (4 - (size_t) buff->head) & 3;
 687                 /* Send buffer if it is for v0 */
 688                 if (buff->head + len + pad > buff->end || m->reserved) {
 689                         sb_queue_tail(ipvs, ms);
 690                         ms->sync_buff = NULL;
 691                         buff = NULL;
 692                         pad = 0;
 693                 }
 694         }
 695
 696         if (!buff) {
 697                 buff = ip_vs_sync_buff_create(ipvs);
 698                 if (!buff) {
 699                         spin_unlock_bh(&ipvs->sync_buff_lock);
 700                         pr_err("ip_vs_sync_buff_create failed.\n");
 701                         return;
 702                 }
 703                 ms->sync_buff = buff;
 704                 m = buff->mesg;
 705         }
 706
 707         p = buff->head;
 708         buff->head += pad + len;
 709         m->size = htons(ntohs(m->size) + pad + len);
 710         /* Add ev. padding from prev. sync_conn */
 711         while (pad--)
 712                 *(p++) = 0;
 713
 714         s = (union ip_vs_sync_conn *)p;
 715
 716         /* Set message type  & copy members */
 717         s->v4.type = (cp->af == AF_INET6 ? STYPE_F_INET6 : 0);
 718         s->v4.ver_size = htons(len & SVER_MASK);        /* Version 0 */
 719         s->v4.flags = htonl(cp->flags & ~IP_VS_CONN_F_HASHED);
 720         s->v4.state = htons(cp->state);
 721         s->v4.protocol = cp->protocol;
 722         s->v4.cport = cp->cport;
 723         s->v4.vport = cp->vport;
 724         s->v4.dport = cp->dport;
 725         s->v4.fwmark = htonl(cp->fwmark);
 726         s->v4.timeout = htonl(cp->timeout / HZ);
 727         m->nr_conns++;
 728
 729 #ifdef CONFIG_IP_VS_IPV6
 730         if (cp->af == AF_INET6) {
 731                 p += sizeof(struct ip_vs_sync_v6);
 732                 s->v6.caddr = cp->caddr.in6;
 733                 s->v6.vaddr = cp->vaddr.in6;
 734                 s->v6.daddr = cp->daddr.in6;
 735         } else
 736 #endif
 737         {
 738                 p += sizeof(struct ip_vs_sync_v4);      /* options ptr */
 739                 s->v4.caddr = cp->caddr.ip;
 740                 s->v4.vaddr = cp->vaddr.ip;
 741                 s->v4.daddr = cp->daddr.ip;
 742         }
 743         if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
 744                 *(p++) = IPVS_OPT_SEQ_DATA;
 745                 *(p++) = sizeof(struct ip_vs_sync_conn_options);
 746                 hton_seq((struct ip_vs_seq *)p, &cp->in_seq);
 747                 p += sizeof(struct ip_vs_seq);
 748                 hton_seq((struct ip_vs_seq *)p, &cp->out_seq);
 749                 p += sizeof(struct ip_vs_seq);
 750         }
 751         /* Handle pe data */
 752         if (cp->pe_data_len && cp->pe_data) {
 753                 *(p++) = IPVS_OPT_PE_DATA;
 754                 *(p++) = cp->pe_data_len;
 755                 memcpy(p, cp->pe_data, cp->pe_data_len);
 756                 p += cp->pe_data_len;
 757                 if (pe_name_len) {
 758                         /* Add PE_NAME */
 759                         *(p++) = IPVS_OPT_PE_NAME;
 760                         *(p++) = pe_name_len;
 761                         memcpy(p, cp->pe->name, pe_name_len);
 762                         p += pe_name_len;
 763                 }
 764         }
 765
 766         spin_unlock_bh(&ipvs->sync_buff_lock);
 767
 768 control:
 769         /* synchronize its controller if it has */
 770         cp = cp->control;
 771         if (!cp)
 772                 return;
 773         if (cp->flags & IP_VS_CONN_F_TEMPLATE)
 774                 pkts = atomic_add_return(1, &cp->in_pkts);
 775         else
 776                 pkts = sysctl_sync_threshold(ipvs);
 777         goto sloop;
 778 }
 779
 780 /*
 781  *  fill_param used by version 1
 782  */
 783 static inline int
 784 ip_vs_conn_fill_param_sync(struct net *net, int af, union ip_vs_sync_conn *sc,
 785                            struct ip_vs_conn_param *p,
 786                            __u8 *pe_data, unsigned int pe_data_len,
 787                            __u8 *pe_name, unsigned int pe_name_len)
 788 {
 789 #ifdef CONFIG_IP_VS_IPV6
 790         if (af == AF_INET6)
 791                 ip_vs_conn_fill_param(net, af, sc->v6.protocol,
 792                                       (const union nf_inet_addr *)&sc->v6.caddr,
 793                                       sc->v6.cport,
 794                                       (const union nf_inet_addr *)&sc->v6.vaddr,
 795                                       sc->v6.vport, p);
 796         else
 797 #endif
 798                 ip_vs_conn_fill_param(net, af, sc->v4.protocol,
 799                                       (const union nf_inet_addr *)&sc->v4.caddr,
 800                                       sc->v4.cport,
 801                                       (const union nf_inet_addr *)&sc->v4.vaddr,
 802                                       sc->v4.vport, p);
 803         /* Handle pe data */
 804         if (pe_data_len) {
 805                 if (pe_name_len) {
 806                         char buff[IP_VS_PENAME_MAXLEN+1];
 807
 808                         memcpy(buff, pe_name, pe_name_len);
 809                         buff[pe_name_len]=0;
 810                         p->pe = __ip_vs_pe_getbyname(buff);
 811                         if (!p->pe) {
 812                                 IP_VS_DBG(3, "BACKUP, no %s engine found/loaded\n",
 813                                              buff);
 814                                 return 1;
 815                         }
 816                 } else {
 817                         IP_VS_ERR_RL("BACKUP, Invalid PE parameters\n");
 818                         return 1;
 819                 }
 820
 821                 p->pe_data = kmemdup(pe_data, pe_data_len, GFP_ATOMIC);
 822                 if (!p->pe_data) {
 823                         module_put(p->pe->module);
 824                         return -ENOMEM;
 825                 }
 826                 p->pe_data_len = pe_data_len;
 827         }
 828         return 0;
 829 }
 830
 831 /*
 832  *  Connection Add / Update.
 833  *  Common for version 0 and 1 reception of backup sync_conns.
 834  *  Param: ...
 835  *         timeout is in sec.
 836  */
 837 static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
 838                             unsigned int flags, unsigned int state,
 839                             unsigned int protocol, unsigned int type,
 840                             const union nf_inet_addr *daddr, __be16 dport,
 841                             unsigned long timeout, __u32 fwmark,
 842                             struct ip_vs_sync_conn_options *opt)
 843 {
 844         struct ip_vs_dest *dest;
 845         struct ip_vs_conn *cp;
 846         struct netns_ipvs *ipvs = net_ipvs(net);
 847
 848         if (!(flags & IP_VS_CONN_F_TEMPLATE))
 849                 cp = ip_vs_conn_in_get(param);
 850         else
 851                 cp = ip_vs_ct_in_get(param);
 852
 853         if (cp) {
 854                 /* Free pe_data */
 855                 kfree(param->pe_data);
 856
 857                 dest = cp->dest;
 858                 spin_lock_bh(&cp->lock);
 859                 if ((cp->flags ^ flags) & IP_VS_CONN_F_INACTIVE &&
 860                     !(flags & IP_VS_CONN_F_TEMPLATE) && dest) {
 861                         if (flags & IP_VS_CONN_F_INACTIVE) {
 862                                 atomic_dec(&dest->activeconns);
 863                                 atomic_inc(&dest->inactconns);
 864                         } else {
 865                                 atomic_inc(&dest->activeconns);
 866                                 atomic_dec(&dest->inactconns);
 867                         }
 868                 }
 869                 flags &= IP_VS_CONN_F_BACKUP_UPD_MASK;
 870                 flags |= cp->flags & ~IP_VS_CONN_F_BACKUP_UPD_MASK;
 871                 cp->flags = flags;
 872                 spin_unlock_bh(&cp->lock);
 873                 if (!dest)
 874                         ip_vs_try_bind_dest(cp);
 875         } else {
 876                 /*
 877                  * Find the appropriate destination for the connection.
 878                  * If it is not found the connection will remain unbound
 879                  * but still handled.
 880                  */
 881                 rcu_read_lock();
 882                 /* This function is only invoked by the synchronization
 883                  * code. We do not currently support heterogeneous pools
 884                  * with synchronization, so we can make the assumption that
 885                  * the svc_af is the same as the dest_af
 886                  */
 887                 dest = ip_vs_find_dest(net, type, type, daddr, dport,
 888                                        param->vaddr, param->vport, protocol,
 889                                        fwmark, flags);
 890
 891                 cp = ip_vs_conn_new(param, type, daddr, dport, flags, dest,
 892                                     fwmark);
 893                 rcu_read_unlock();
 894                 if (!cp) {
 895                         kfree(param->pe_data);
 896                         IP_VS_DBG(2, "BACKUP, add new conn. failed\n");
 897                         return;
 898                 }
 899         }
 900
 901         if (opt)
 902                 memcpy(&cp->in_seq, opt, sizeof(*opt));
 903         atomic_set(&cp->in_pkts, sysctl_sync_threshold(ipvs));
 904         cp->state = state;
 905         cp->old_state = cp->state;
 906         /*
 907          * For Ver 0 messages style
 908          *  - Not possible to recover the right timeout for templates
 909          *  - can not find the right fwmark
 910          *    virtual service. If needed, we can do it for
 911          *    non-fwmark persistent services.
 912          * Ver 1 messages style.
 913          *  - No problem.
 914          */
 915         if (timeout) {
 916                 if (timeout > MAX_SCHEDULE_TIMEOUT / HZ)
 917                         timeout = MAX_SCHEDULE_TIMEOUT / HZ;
 918                 cp->timeout = timeout*HZ;
 919         } else {
 920                 struct ip_vs_proto_data *pd;
 921
 922                 pd = ip_vs_proto_data_get(net, protocol);
 923                 if (!(flags & IP_VS_CONN_F_TEMPLATE) && pd && pd->timeout_table)
 924                         cp->timeout = pd->timeout_table[state];
 925                 else
 926                         cp->timeout = (3*60*HZ);
 927         }
 928         ip_vs_conn_put(cp);
 929 }
 930
 931 /*
 932  *  Process received multicast message for Version 0
 933  */
 934 static void ip_vs_process_message_v0(struct net *net, const char *buffer,
 935                                      const size_t buflen)
 936 {
 937         struct ip_vs_sync_mesg_v0 *m = (struct ip_vs_sync_mesg_v0 *)buffer;
 938         struct ip_vs_sync_conn_v0 *s;
 939         struct ip_vs_sync_conn_options *opt;
 940         struct ip_vs_protocol *pp;
 941         struct ip_vs_conn_param param;
 942         char *p;
 943         int i;
 944
 945         p = (char *)buffer + sizeof(struct ip_vs_sync_mesg_v0);
 946         for (i=0; i<m->nr_conns; i++) {
 947                 unsigned int flags, state;
 948
 949                 if (p + SIMPLE_CONN_SIZE > buffer+buflen) {
 950                         IP_VS_ERR_RL("BACKUP v0, bogus conn\n");
 951                         return;
 952                 }
 953                 s = (struct ip_vs_sync_conn_v0 *) p;
 954                 flags = ntohs(s->flags) | IP_VS_CONN_F_SYNC;
 955                 flags &= ~IP_VS_CONN_F_HASHED;
 956                 if (flags & IP_VS_CONN_F_SEQ_MASK) {
 957                         opt = (struct ip_vs_sync_conn_options *)&s[1];
 958                         p += FULL_CONN_SIZE;
 959                         if (p > buffer+buflen) {
 960                                 IP_VS_ERR_RL("BACKUP v0, Dropping buffer bogus conn options\n");
 961                                 return;
 962                         }
 963                 } else {
 964                         opt = NULL;
 965                         p += SIMPLE_CONN_SIZE;
 966                 }
 967
 968                 state = ntohs(s->state);
 969                 if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
 970                         pp = ip_vs_proto_get(s->protocol);
 971                         if (!pp) {
 972                                 IP_VS_DBG(2, "BACKUP v0, Unsupported protocol %u\n",
 973                                         s->protocol);
 974                                 continue;
 975                         }
 976                         if (state >= pp->num_states) {
 977                                 IP_VS_DBG(2, "BACKUP v0, Invalid %s state %u\n",
 978                                         pp->name, state);
 979                                 continue;
 980                         }
 981                 } else {
 982                         /* protocol in templates is not used for state/timeout */
 983                         if (state > 0) {
 984                                 IP_VS_DBG(2, "BACKUP v0, Invalid template state %u\n",
 985                                         state);
 986                                 state = 0;
 987                         }
 988                 }
 989
 990                 ip_vs_conn_fill_param(net, AF_INET, s->protocol,
 991                                       (const union nf_inet_addr *)&s->caddr,
 992                                       s->cport,
 993                                       (const union nf_inet_addr *)&s->vaddr,
 994                                       s->vport, &param);
 995
 996                 /* Send timeout as Zero */
 997                 ip_vs_proc_conn(net, &param, flags, state, s->protocol, AF_INET,
 998                                 (union nf_inet_addr *)&s->daddr, s->dport,
 999                                 0, 0, opt);
1000         }
1001 }
1002
1003 /*
1004  * Handle options
1005  */
1006 static inline int ip_vs_proc_seqopt(__u8 *p, unsigned int plen,
1007                                     __u32 *opt_flags,
1008                                     struct ip_vs_sync_conn_options *opt)
1009 {
1010         struct ip_vs_sync_conn_options *topt;
1011
1012         topt = (struct ip_vs_sync_conn_options *)p;
1013
1014         if (plen != sizeof(struct ip_vs_sync_conn_options)) {
1015                 IP_VS_DBG(2, "BACKUP, bogus conn options length\n");
1016                 return -EINVAL;
1017         }
1018         if (*opt_flags & IPVS_OPT_F_SEQ_DATA) {
1019                 IP_VS_DBG(2, "BACKUP, conn options found twice\n");
1020                 return -EINVAL;
1021         }
1022         ntoh_seq(&topt->in_seq, &opt->in_seq);
1023         ntoh_seq(&topt->out_seq, &opt->out_seq);
1024         *opt_flags |= IPVS_OPT_F_SEQ_DATA;
1025         return 0;
1026 }
1027
1028 static int ip_vs_proc_str(__u8 *p, unsigned int plen, unsigned int *data_len,
1029                           __u8 **data, unsigned int maxlen,
1030                           __u32 *opt_flags, __u32 flag)
1031 {
1032         if (plen > maxlen) {
1033                 IP_VS_DBG(2, "BACKUP, bogus par.data len > %d\n", maxlen);
1034                 return -EINVAL;
1035         }
1036         if (*opt_flags & flag) {
1037                 IP_VS_DBG(2, "BACKUP, Par.data found twice 0x%x\n", flag);
1038                 return -EINVAL;
1039         }
1040         *data_len = plen;
1041         *data = p;
1042         *opt_flags |= flag;
1043         return 0;
1044 }
1045 /*
1046  *   Process a Version 1 sync. connection
1047  */
1048 static inline int ip_vs_proc_sync_conn(struct net *net, __u8 *p, __u8 *msg_end)
1049 {
1050         struct ip_vs_sync_conn_options opt;
1051         union  ip_vs_sync_conn *s;
1052         struct ip_vs_protocol *pp;
1053         struct ip_vs_conn_param param;
1054         __u32 flags;
1055         unsigned int af, state, pe_data_len=0, pe_name_len=0;
1056         __u8 *pe_data=NULL, *pe_name=NULL;
1057         __u32 opt_flags=0;
1058         int retc=0;
1059
1060         s = (union ip_vs_sync_conn *) p;
1061
1062         if (s->v6.type & STYPE_F_INET6) {
1063 #ifdef CONFIG_IP_VS_IPV6
1064                 af = AF_INET6;
1065                 p += sizeof(struct ip_vs_sync_v6);
1066 #else
1067                 IP_VS_DBG(3,"BACKUP, IPv6 msg received, and IPVS is not compiled for IPv6\n");
1068                 retc = 10;
1069                 goto out;
1070 #endif
1071         } else if (!s->v4.type) {
1072                 af = AF_INET;
1073                 p += sizeof(struct ip_vs_sync_v4);
1074         } else {
1075                 return -10;
1076         }
1077         if (p > msg_end)
1078                 return -20;
1079
1080         /* Process optional params check Type & Len. */
1081         while (p < msg_end) {
1082                 int ptype;
1083                 int plen;
1084
1085                 if (p+2 > msg_end)
1086                         return -30;
1087                 ptype = *(p++);
1088                 plen  = *(p++);
1089
1090                 if (!plen || ((p + plen) > msg_end))
1091                         return -40;
1092                 /* Handle seq option  p = param data */
1093                 switch (ptype & ~IPVS_OPT_F_PARAM) {
1094                 case IPVS_OPT_SEQ_DATA:
1095                         if (ip_vs_proc_seqopt(p, plen, &opt_flags, &opt))
1096                                 return -50;
1097                         break;
1098
1099                 case IPVS_OPT_PE_DATA:
1100                         if (ip_vs_proc_str(p, plen, &pe_data_len, &pe_data,
1101                                            IP_VS_PEDATA_MAXLEN, &opt_flags,
1102                                            IPVS_OPT_F_PE_DATA))
1103                                 return -60;
1104                         break;
1105
1106                 case IPVS_OPT_PE_NAME:
1107                         if (ip_vs_proc_str(p, plen,&pe_name_len, &pe_name,
1108                                            IP_VS_PENAME_MAXLEN, &opt_flags,
1109                                            IPVS_OPT_F_PE_NAME))
1110                                 return -70;
1111                         break;
1112
1113                 default:
1114                         /* Param data mandatory ? */
1115                         if (!(ptype & IPVS_OPT_F_PARAM)) {
1116                                 IP_VS_DBG(3, "BACKUP, Unknown mandatory param %d found\n",
1117                                           ptype & ~IPVS_OPT_F_PARAM);
1118                                 retc = 20;
1119                                 goto out;
1120                         }
1121                 }
1122                 p += plen;  /* Next option */
1123         }
1124
1125         /* Get flags and Mask off unsupported */
1126         flags  = ntohl(s->v4.flags) & IP_VS_CONN_F_BACKUP_MASK;
1127         flags |= IP_VS_CONN_F_SYNC;
1128         state = ntohs(s->v4.state);
1129
1130         if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
1131                 pp = ip_vs_proto_get(s->v4.protocol);
1132                 if (!pp) {
1133                         IP_VS_DBG(3,"BACKUP, Unsupported protocol %u\n",
1134                                 s->v4.protocol);
1135                         retc = 30;
1136                         goto out;
1137                 }
1138                 if (state >= pp->num_states) {
1139                         IP_VS_DBG(3, "BACKUP, Invalid %s state %u\n",
1140                                 pp->name, state);
1141                         retc = 40;
1142                         goto out;
1143                 }
1144         } else {
1145                 /* protocol in templates is not used for state/timeout */
1146                 if (state > 0) {
1147                         IP_VS_DBG(3, "BACKUP, Invalid template state %u\n",
1148                                 state);
1149                         state = 0;
1150                 }
1151         }
1152         if (ip_vs_conn_fill_param_sync(net, af, s, &param, pe_data,
1153                                        pe_data_len, pe_name, pe_name_len)) {
1154                 retc = 50;
1155                 goto out;
1156         }
1157         /* If only IPv4, just silent skip IPv6 */
1158         if (af == AF_INET)
1159                 ip_vs_proc_conn(net, &param, flags, state, s->v4.protocol, af,
1160                                 (union nf_inet_addr *)&s->v4.daddr, s->v4.dport,
1161                                 ntohl(s->v4.timeout), ntohl(s->v4.fwmark),
1162                                 (opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1163                                 );
1164 #ifdef CONFIG_IP_VS_IPV6
1165         else
1166                 ip_vs_proc_conn(net, &param, flags, state, s->v6.protocol, af,
1167                                 (union nf_inet_addr *)&s->v6.daddr, s->v6.dport,
1168                                 ntohl(s->v6.timeout), ntohl(s->v6.fwmark),
1169                                 (opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1170                                 );
1171 #endif
1172         return 0;
1173         /* Error exit */
1174 out:
1175         IP_VS_DBG(2, "BACKUP, Single msg dropped err:%d\n", retc);
1176         return retc;
1177
1178 }
1179 /*
1180  *      Process received multicast message and create the corresponding
1181  *      ip_vs_conn entries.
1182  *      Handles Version 0 & 1
1183  */
1184 static void ip_vs_process_message(struct net *net, __u8 *buffer,
1185                                   const size_t buflen)
1186 {
1187         struct netns_ipvs *ipvs = net_ipvs(net);
1188         struct ip_vs_sync_mesg *m2 = (struct ip_vs_sync_mesg *)buffer;
1189         __u8 *p, *msg_end;
1190         int i, nr_conns;
1191
1192         if (buflen < sizeof(struct ip_vs_sync_mesg_v0)) {
1193                 IP_VS_DBG(2, "BACKUP, message header too short\n");
1194                 return;
1195         }
1196
1197         if (buflen != ntohs(m2->size)) {
1198                 IP_VS_DBG(2, "BACKUP, bogus message size\n");
1199                 return;
1200         }
1201         /* SyncID sanity check */
1202         if (ipvs->backup_syncid != 0 && m2->syncid != ipvs->backup_syncid) {
1203                 IP_VS_DBG(7, "BACKUP, Ignoring syncid = %d\n", m2->syncid);
1204                 return;
1205         }
1206         /* Handle version 1  message */
1207         if ((m2->version == SYNC_PROTO_VER) && (m2->reserved == 0)
1208             && (m2->spare == 0)) {
1209
1210                 msg_end = buffer + sizeof(struct ip_vs_sync_mesg);
1211                 nr_conns = m2->nr_conns;
1212
1213                 for (i=0; i<nr_conns; i++) {
1214                         union ip_vs_sync_conn *s;
1215                         unsigned int size;
1216                         int retc;
1217
1218                         p = msg_end;
1219                         if (p + sizeof(s->v4) > buffer+buflen) {
1220                                 IP_VS_ERR_RL("BACKUP, Dropping buffer, to small\n");
1221                                 return;
1222                         }
1223                         s = (union ip_vs_sync_conn *)p;
1224                         size = ntohs(s->v4.ver_size) & SVER_MASK;
1225                         msg_end = p + size;
1226                         /* Basic sanity checks */
1227                         if (msg_end  > buffer+buflen) {
1228                                 IP_VS_ERR_RL("BACKUP, Dropping buffer, msg > buffer\n");
1229                                 return;
1230                         }
1231                         if (ntohs(s->v4.ver_size) >> SVER_SHIFT) {
1232                                 IP_VS_ERR_RL("BACKUP, Dropping buffer, Unknown version %d\n",
1233                                               ntohs(s->v4.ver_size) >> SVER_SHIFT);
1234                                 return;
1235                         }
1236                         /* Process a single sync_conn */
1237                         retc = ip_vs_proc_sync_conn(net, p, msg_end);
1238                         if (retc < 0) {
1239                                 IP_VS_ERR_RL("BACKUP, Dropping buffer, Err: %d in decoding\n",
1240                                              retc);
1241                                 return;
1242                         }
1243                         /* Make sure we have 32 bit alignment */
1244                         msg_end = p + ((size + 3) & ~3);
1245                 }
1246         } else {
1247                 /* Old type of message */
1248                 ip_vs_process_message_v0(net, buffer, buflen);
1249                 return;
1250         }
1251 }
1252
1253
1254 /*
1255  *      Setup sndbuf (mode=1) or rcvbuf (mode=0)
1256  */
1257 static void set_sock_size(struct sock *sk, int mode, int val)
1258 {
1259         /* setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)); */
1260         /* setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)); */
1261         lock_sock(sk);
1262         if (mode) {
1263                 val = clamp_t(int, val, (SOCK_MIN_SNDBUF + 1) / 2,
1264                               sysctl_wmem_max);
1265                 sk->sk_sndbuf = val * 2;
1266                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1267         } else {
1268                 val = clamp_t(int, val, (SOCK_MIN_RCVBUF + 1) / 2,
1269                               sysctl_rmem_max);
1270                 sk->sk_rcvbuf = val * 2;
1271                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1272         }
1273         release_sock(sk);
1274 }
1275
1276 /*
1277  *      Setup loopback of outgoing multicasts on a sending socket
1278  */
1279 static void set_mcast_loop(struct sock *sk, u_char loop)
1280 {
1281         struct inet_sock *inet = inet_sk(sk);
1282
1283         /* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */
1284         lock_sock(sk);
1285         inet->mc_loop = loop ? 1 : 0;
1286         release_sock(sk);
1287 }
1288
1289 /*
1290  *      Specify TTL for outgoing multicasts on a sending socket
1291  */
1292 static void set_mcast_ttl(struct sock *sk, u_char ttl)
1293 {
1294         struct inet_sock *inet = inet_sk(sk);
1295
1296         /* setsockopt(sock, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); */
1297         lock_sock(sk);
1298         inet->mc_ttl = ttl;
1299         release_sock(sk);
1300 }
1301
1302 /*
1303  *      Specifiy default interface for outgoing multicasts
1304  */
1305 static int set_mcast_if(struct sock *sk, char *ifname)
1306 {
1307         struct net_device *dev;
1308         struct inet_sock *inet = inet_sk(sk);
1309         struct net *net = sock_net(sk);
1310
1311         dev = __dev_get_by_name(net, ifname);
1312         if (!dev)
1313                 return -ENODEV;
1314
1315         if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1316                 return -EINVAL;
1317
1318         lock_sock(sk);
1319         inet->mc_index = dev->ifindex;
1320         /*  inet->mc_addr  = 0; */
1321         release_sock(sk);
1322
1323         return 0;
1324 }
1325
1326
1327 /*
1328  *      Set the maximum length of sync message according to the
1329  *      specified interface's MTU.
1330  */
1331 static int set_sync_mesg_maxlen(struct net *net, int sync_state)
1332 {
1333         struct netns_ipvs *ipvs = net_ipvs(net);
1334         struct net_device *dev;
1335         int num;
1336
1337         if (sync_state == IP_VS_STATE_MASTER) {
1338                 dev = __dev_get_by_name(net, ipvs->master_mcast_ifn);
1339                 if (!dev)
1340                         return -ENODEV;
1341
1342                 num = (dev->mtu - sizeof(struct iphdr) -
1343                        sizeof(struct udphdr) -
1344                        SYNC_MESG_HEADER_LEN - 20) / SIMPLE_CONN_SIZE;
1345                 ipvs->send_mesg_maxlen = SYNC_MESG_HEADER_LEN +
1346                         SIMPLE_CONN_SIZE * min(num, MAX_CONNS_PER_SYNCBUFF);
1347                 IP_VS_DBG(7, "setting the maximum length of sync sending "
1348                           "message %d.\n", ipvs->send_mesg_maxlen);
1349         } else if (sync_state == IP_VS_STATE_BACKUP) {
1350                 dev = __dev_get_by_name(net, ipvs->backup_mcast_ifn);
1351                 if (!dev)
1352                         return -ENODEV;
1353
1354                 ipvs->recv_mesg_maxlen = dev->mtu -
1355                         sizeof(struct iphdr) - sizeof(struct udphdr);
1356                 IP_VS_DBG(7, "setting the maximum length of sync receiving "
1357                           "message %d.\n", ipvs->recv_mesg_maxlen);
1358         }
1359
1360         return 0;
1361 }
1362
1363
1364 /*
1365  *      Join a multicast group.
1366  *      the group is specified by a class D multicast address 224.0.0.0/8
1367  *      in the in_addr structure passed in as a parameter.
1368  */
1369 static int
1370 join_mcast_group(struct sock *sk, struct in_addr *addr, char *ifname)
1371 {
1372         struct net *net = sock_net(sk);
1373         struct ip_mreqn mreq;
1374         struct net_device *dev;
1375         int ret;
1376
1377         memset(&mreq, 0, sizeof(mreq));
1378         memcpy(&mreq.imr_multiaddr, addr, sizeof(struct in_addr));
1379
1380         dev = __dev_get_by_name(net, ifname);
1381         if (!dev)
1382                 return -ENODEV;
1383         if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1384                 return -EINVAL;
1385
1386         mreq.imr_ifindex = dev->ifindex;
1387
1388         lock_sock(sk);
1389         ret = ip_mc_join_group(sk, &mreq);
1390         release_sock(sk);
1391
1392         return ret;
1393 }
1394
1395
1396 static int bind_mcastif_addr(struct socket *sock, char *ifname)
1397 {
1398         struct net *net = sock_net(sock->sk);
1399         struct net_device *dev;
1400         __be32 addr;
1401         struct sockaddr_in sin;
1402
1403         dev = __dev_get_by_name(net, ifname);
1404         if (!dev)
1405                 return -ENODEV;
1406
1407         addr = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
1408         if (!addr)
1409                 pr_err("You probably need to specify IP address on "
1410                        "multicast interface.\n");
1411
1412         IP_VS_DBG(7, "binding socket with (%s) %pI4\n",
1413                   ifname, &addr);
1414
1415         /* Now bind the socket with the address of multicast interface */
1416         sin.sin_family       = AF_INET;
1417         sin.sin_addr.s_addr  = addr;
1418         sin.sin_port         = 0;
1419
1420         return sock->ops->bind(sock, (struct sockaddr*)&sin, sizeof(sin));
1421 }
1422
1423 /*
1424  *      Set up sending multicast socket over UDP
1425  */
1426 static struct socket *make_send_sock(struct net *net, int id)
1427 {
1428         struct netns_ipvs *ipvs = net_ipvs(net);
1429         /* multicast addr */
1430         struct sockaddr_in mcast_addr = {
1431                 .sin_family             = AF_INET,
1432                 .sin_port               = cpu_to_be16(IP_VS_SYNC_PORT + id),
1433                 .sin_addr.s_addr        = cpu_to_be32(IP_VS_SYNC_GROUP),
1434         };
1435         struct socket *sock;
1436         int result;
1437
1438         /* First create a socket move it to right name space later */
1439         result = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock);
1440         if (result < 0) {
1441                 pr_err("Error during creation of socket; terminating\n");
1442                 return ERR_PTR(result);
1443         }
1444         /*
1445          * Kernel sockets that are a part of a namespace, should not
1446          * hold a reference to a namespace in order to allow to stop it.
1447          * After sk_change_net should be released using sk_release_kernel.
1448          */
1449         sk_change_net(sock->sk, net);
1450         result = set_mcast_if(sock->sk, ipvs->master_mcast_ifn);
1451         if (result < 0) {
1452                 pr_err("Error setting outbound mcast interface\n");
1453                 goto error;
1454         }
1455
1456         set_mcast_loop(sock->sk, 0);
1457         set_mcast_ttl(sock->sk, 1);
1458         result = sysctl_sync_sock_size(ipvs);
1459         if (result > 0)
1460                 set_sock_size(sock->sk, 1, result);
1461
1462         result = bind_mcastif_addr(sock, ipvs->master_mcast_ifn);
1463         if (result < 0) {
1464                 pr_err("Error binding address of the mcast interface\n");
1465                 goto error;
1466         }
1467
1468         result = sock->ops->connect(sock, (struct sockaddr *) &mcast_addr,
1469                         sizeof(struct sockaddr), 0);
1470         if (result < 0) {
1471                 pr_err("Error connecting to the multicast addr\n");
1472                 goto error;
1473         }
1474
1475         return sock;
1476
1477 error:
1478         sk_release_kernel(sock->sk);
1479         return ERR_PTR(result);
1480 }
1481
1482
1483 /*
1484  *      Set up receiving multicast socket over UDP
1485  */
1486 static struct socket *make_receive_sock(struct net *net, int id)
1487 {
1488         struct netns_ipvs *ipvs = net_ipvs(net);
1489         /* multicast addr */
1490         struct sockaddr_in mcast_addr = {
1491                 .sin_family             = AF_INET,
1492                 .sin_port               = cpu_to_be16(IP_VS_SYNC_PORT + id),
1493                 .sin_addr.s_addr        = cpu_to_be32(IP_VS_SYNC_GROUP),
1494         };
1495         struct socket *sock;
1496         int result;
1497
1498         /* First create a socket */
1499         result = sock_create_kern(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &sock);
1500         if (result < 0) {
1501                 pr_err("Error during creation of socket; terminating\n");
1502                 return ERR_PTR(result);
1503         }
1504         /*
1505          * Kernel sockets that are a part of a namespace, should not
1506          * hold a reference to a namespace in order to allow to stop it.
1507          * After sk_change_net should be released using sk_release_kernel.
1508          */
1509         sk_change_net(sock->sk, net);
1510         /* it is equivalent to the REUSEADDR option in user-space */
1511         sock->sk->sk_reuse = SK_CAN_REUSE;
1512         result = sysctl_sync_sock_size(ipvs);
1513         if (result > 0)
1514                 set_sock_size(sock->sk, 0, result);
1515
1516         result = sock->ops->bind(sock, (struct sockaddr *) &mcast_addr,
1517                         sizeof(struct sockaddr));
1518         if (result < 0) {
1519                 pr_err("Error binding to the multicast addr\n");
1520                 goto error;
1521         }
1522
1523         /* join the multicast group */
1524         result = join_mcast_group(sock->sk,
1525                         (struct in_addr *) &mcast_addr.sin_addr,
1526                         ipvs->backup_mcast_ifn);
1527         if (result < 0) {
1528                 pr_err("Error joining to the multicast group\n");
1529                 goto error;
1530         }
1531
1532         return sock;
1533
1534 error:
1535         sk_release_kernel(sock->sk);
1536         return ERR_PTR(result);
1537 }
1538
1539
1540 static int
1541 ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length)
1542 {
1543         struct msghdr   msg = {.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL};
1544         struct kvec     iov;
1545         int             len;
1546
1547         EnterFunction(7);
1548         iov.iov_base     = (void *)buffer;
1549         iov.iov_len      = length;
1550
1551         len = kernel_sendmsg(sock, &msg, &iov, 1, (size_t)(length));
1552
1553         LeaveFunction(7);
1554         return len;
1555 }
1556
1557 static int
1558 ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg)
1559 {
1560         int msize;
1561         int ret;
1562
1563         msize = ntohs(msg->size);
1564
1565         ret = ip_vs_send_async(sock, (char *)msg, msize);
1566         if (ret >= 0 || ret == -EAGAIN)
1567                 return ret;
1568         pr_err("ip_vs_send_async error %d\n", ret);
1569         return 0;
1570 }
1571
1572 static int
1573 ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
1574 {
1575         struct msghdr           msg = {NULL,};
1576         struct kvec             iov;
1577         int                     len;
1578
1579         EnterFunction(7);
1580
1581         /* Receive a packet */
1582         iov.iov_base     = buffer;
1583         iov.iov_len      = (size_t)buflen;
1584
1585         len = kernel_recvmsg(sock, &msg, &iov, 1, buflen, MSG_DONTWAIT);
1586
1587         if (len < 0)
1588                 return len;
1589
1590         LeaveFunction(7);
1591         return len;
1592 }
1593
1594 /* Wakeup the master thread for sending */
1595 static void master_wakeup_work_handler(struct work_struct *work)
1596 {
1597         struct ipvs_master_sync_state *ms =
1598                 container_of(work, struct ipvs_master_sync_state,
1599                              master_wakeup_work.work);
1600         struct netns_ipvs *ipvs = ms->ipvs;
1601
1602         spin_lock_bh(&ipvs->sync_lock);
1603         if (ms->sync_queue_len &&
1604             ms->sync_queue_delay < IPVS_SYNC_WAKEUP_RATE) {
1605                 ms->sync_queue_delay = IPVS_SYNC_WAKEUP_RATE;
1606                 wake_up_process(ms->master_thread);
1607         }
1608         spin_unlock_bh(&ipvs->sync_lock);
1609 }
1610
1611 /* Get next buffer to send */
1612 static inline struct ip_vs_sync_buff *
1613 next_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
1614 {
1615         struct ip_vs_sync_buff *sb;
1616
1617         sb = sb_dequeue(ipvs, ms);
1618         if (sb)
1619                 return sb;
1620         /* Do not delay entries in buffer for more than 2 seconds */
1621         return get_curr_sync_buff(ipvs, ms, IPVS_SYNC_FLUSH_TIME);
1622 }
1623
1624 static int sync_thread_master(void *data)
1625 {
1626         struct ip_vs_sync_thread_data *tinfo = data;
1627         struct netns_ipvs *ipvs = net_ipvs(tinfo->net);
1628         struct ipvs_master_sync_state *ms = &ipvs->ms[tinfo->id];
1629         struct sock *sk = tinfo->sock->sk;
1630         struct ip_vs_sync_buff *sb;
1631
1632         pr_info("sync thread started: state = MASTER, mcast_ifn = %s, "
1633                 "syncid = %d, id = %d\n",
1634                 ipvs->master_mcast_ifn, ipvs->master_syncid, tinfo->id);
1635
1636         for (;;) {
1637                 sb = next_sync_buff(ipvs, ms);
1638                 if (unlikely(kthread_should_stop()))
1639                         break;
1640                 if (!sb) {
1641                         schedule_timeout(IPVS_SYNC_CHECK_PERIOD);
1642                         continue;
1643                 }
1644                 while (ip_vs_send_sync_msg(tinfo->sock, sb->mesg) < 0) {
1645                         /* (Ab)use interruptible sleep to avoid increasing
1646                          * the load avg.
1647                          */
1648                         __wait_event_interruptible(*sk_sleep(sk),
1649                                                    sock_writeable(sk) ||
1650                                                    kthread_should_stop());
1651                         if (unlikely(kthread_should_stop()))
1652                                 goto done;
1653                 }
1654                 ip_vs_sync_buff_release(sb);
1655         }
1656
1657 done:
1658         __set_current_state(TASK_RUNNING);
1659         if (sb)
1660                 ip_vs_sync_buff_release(sb);
1661
1662         /* clean up the sync_buff queue */
1663         while ((sb = sb_dequeue(ipvs, ms)))
1664                 ip_vs_sync_buff_release(sb);
1665         __set_current_state(TASK_RUNNING);
1666
1667         /* clean up the current sync_buff */
1668         sb = get_curr_sync_buff(ipvs, ms, 0);
1669         if (sb)
1670                 ip_vs_sync_buff_release(sb);
1671
1672         /* release the sending multicast socket */
1673         sk_release_kernel(tinfo->sock->sk);
1674         kfree(tinfo);
1675
1676         return 0;
1677 }
1678
1679
1680 static int sync_thread_backup(void *data)
1681 {
1682         struct ip_vs_sync_thread_data *tinfo = data;
1683         struct netns_ipvs *ipvs = net_ipvs(tinfo->net);
1684         int len;
1685
1686         pr_info("sync thread started: state = BACKUP, mcast_ifn = %s, "
1687                 "syncid = %d, id = %d\n",
1688                 ipvs->backup_mcast_ifn, ipvs->backup_syncid, tinfo->id);
1689
1690         while (!kthread_should_stop()) {
1691                 wait_event_interruptible(*sk_sleep(tinfo->sock->sk),
1692                          !skb_queue_empty(&tinfo->sock->sk->sk_receive_queue)
1693                          || kthread_should_stop());
1694
1695                 /* do we have data now? */
1696                 while (!skb_queue_empty(&(tinfo->sock->sk->sk_receive_queue))) {
1697                         len = ip_vs_receive(tinfo->sock, tinfo->buf,
1698                                         ipvs->recv_mesg_maxlen);
1699                         if (len <= 0) {
1700                                 if (len != -EAGAIN)
1701                                         pr_err("receiving message error\n");
1702                                 break;
1703                         }
1704
1705                         ip_vs_process_message(tinfo->net, tinfo->buf, len);
1706                 }
1707         }
1708
1709         /* release the sending multicast socket */
1710         sk_release_kernel(tinfo->sock->sk);
1711         kfree(tinfo->buf);
1712         kfree(tinfo);
1713
1714         return 0;
1715 }
1716
1717
1718 int start_sync_thread(struct net *net, int state, char *mcast_ifn, __u8 syncid)
1719 {
1720         struct ip_vs_sync_thread_data *tinfo;
1721         struct task_struct **array = NULL, *task;
1722         struct socket *sock;
1723         struct netns_ipvs *ipvs = net_ipvs(net);
1724         char *name;
1725         int (*threadfn)(void *data);
1726         int id, count;
1727         int result = -ENOMEM;
1728
1729         IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1730         IP_VS_DBG(7, "Each ip_vs_sync_conn entry needs %Zd bytes\n",
1731                   sizeof(struct ip_vs_sync_conn_v0));
1732
1733         if (!ipvs->sync_state) {
1734                 count = clamp(sysctl_sync_ports(ipvs), 1, IPVS_SYNC_PORTS_MAX);
1735                 ipvs->threads_mask = count - 1;
1736         } else
1737                 count = ipvs->threads_mask + 1;
1738
1739         if (state == IP_VS_STATE_MASTER) {
1740                 if (ipvs->ms)
1741                         return -EEXIST;
1742
1743                 strlcpy(ipvs->master_mcast_ifn, mcast_ifn,
1744                         sizeof(ipvs->master_mcast_ifn));
1745                 ipvs->master_syncid = syncid;
1746                 name = "ipvs-m:%d:%d";
1747                 threadfn = sync_thread_master;
1748         } else if (state == IP_VS_STATE_BACKUP) {
1749                 if (ipvs->backup_threads)
1750                         return -EEXIST;
1751
1752                 strlcpy(ipvs->backup_mcast_ifn, mcast_ifn,
1753                         sizeof(ipvs->backup_mcast_ifn));
1754                 ipvs->backup_syncid = syncid;
1755                 name = "ipvs-b:%d:%d";
1756                 threadfn = sync_thread_backup;
1757         } else {
1758                 return -EINVAL;
1759         }
1760
1761         if (state == IP_VS_STATE_MASTER) {
1762                 struct ipvs_master_sync_state *ms;
1763
1764                 ipvs->ms = kzalloc(count * sizeof(ipvs->ms[0]), GFP_KERNEL);
1765                 if (!ipvs->ms)
1766                         goto out;
1767                 ms = ipvs->ms;
1768                 for (id = 0; id < count; id++, ms++) {
1769                         INIT_LIST_HEAD(&ms->sync_queue);
1770                         ms->sync_queue_len = 0;
1771                         ms->sync_queue_delay = 0;
1772                         INIT_DELAYED_WORK(&ms->master_wakeup_work,
1773                                           master_wakeup_work_handler);
1774                         ms->ipvs = ipvs;
1775                 }
1776         } else {
1777                 array = kzalloc(count * sizeof(struct task_struct *),
1778                                 GFP_KERNEL);
1779                 if (!array)
1780                         goto out;
1781         }
1782         set_sync_mesg_maxlen(net, state);
1783
1784         tinfo = NULL;
1785         for (id = 0; id < count; id++) {
1786                 if (state == IP_VS_STATE_MASTER)
1787                         sock = make_send_sock(net, id);
1788                 else
1789                         sock = make_receive_sock(net, id);
1790                 if (IS_ERR(sock)) {
1791                         result = PTR_ERR(sock);
1792                         goto outtinfo;
1793                 }
1794                 tinfo = kmalloc(sizeof(*tinfo), GFP_KERNEL);
1795                 if (!tinfo)
1796                         goto outsocket;
1797                 tinfo->net = net;
1798                 tinfo->sock = sock;
1799                 if (state == IP_VS_STATE_BACKUP) {
1800                         tinfo->buf = kmalloc(ipvs->recv_mesg_maxlen,
1801                                              GFP_KERNEL);
1802                         if (!tinfo->buf)
1803                                 goto outtinfo;
1804                 } else {
1805                         tinfo->buf = NULL;
1806                 }
1807                 tinfo->id = id;
1808
1809                 task = kthread_run(threadfn, tinfo, name, ipvs->gen, id);
1810                 if (IS_ERR(task)) {
1811                         result = PTR_ERR(task);
1812                         goto outtinfo;
1813                 }
1814                 tinfo = NULL;
1815                 if (state == IP_VS_STATE_MASTER)
1816                         ipvs->ms[id].master_thread = task;
1817                 else
1818                         array[id] = task;
1819         }
1820
1821         /* mark as active */
1822
1823         if (state == IP_VS_STATE_BACKUP)
1824                 ipvs->backup_threads = array;
1825         spin_lock_bh(&ipvs->sync_buff_lock);
1826         ipvs->sync_state |= state;
1827         spin_unlock_bh(&ipvs->sync_buff_lock);
1828
1829         /* increase the module use count */
1830         ip_vs_use_count_inc();
1831
1832         return 0;
1833
1834 outsocket:
1835         sk_release_kernel(sock->sk);
1836
1837 outtinfo:
1838         if (tinfo) {
1839                 sk_release_kernel(tinfo->sock->sk);
1840                 kfree(tinfo->buf);
1841                 kfree(tinfo);
1842         }
1843         count = id;
1844         while (count-- > 0) {
1845                 if (state == IP_VS_STATE_MASTER)
1846                         kthread_stop(ipvs->ms[count].master_thread);
1847                 else
1848                         kthread_stop(array[count]);
1849         }
1850         kfree(array);
1851
1852 out:
1853         if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
1854                 kfree(ipvs->ms);
1855                 ipvs->ms = NULL;
1856         }
1857         return result;
1858 }
1859
1860
1861 int stop_sync_thread(struct net *net, int state)
1862 {
1863         struct netns_ipvs *ipvs = net_ipvs(net);
1864         struct task_struct **array;
1865         int id;
1866         int retc = -EINVAL;
1867
1868         IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1869
1870         if (state == IP_VS_STATE_MASTER) {
1871                 if (!ipvs->ms)
1872                         return -ESRCH;
1873
1874                 /*
1875                  * The lock synchronizes with sb_queue_tail(), so that we don't
1876                  * add sync buffers to the queue, when we are already in
1877                  * progress of stopping the master sync daemon.
1878                  */
1879
1880                 spin_lock_bh(&ipvs->sync_buff_lock);
1881                 spin_lock(&ipvs->sync_lock);
1882                 ipvs->sync_state &= ~IP_VS_STATE_MASTER;
1883                 spin_unlock(&ipvs->sync_lock);
1884                 spin_unlock_bh(&ipvs->sync_buff_lock);
1885
1886                 retc = 0;
1887                 for (id = ipvs->threads_mask; id >= 0; id--) {
1888                         struct ipvs_master_sync_state *ms = &ipvs->ms[id];
1889                         int ret;
1890
1891                         pr_info("stopping master sync thread %d ...\n",
1892                                 task_pid_nr(ms->master_thread));
1893                         cancel_delayed_work_sync(&ms->master_wakeup_work);
1894                         ret = kthread_stop(ms->master_thread);
1895                         if (retc >= 0)
1896                                 retc = ret;
1897                 }
1898                 kfree(ipvs->ms);
1899                 ipvs->ms = NULL;
1900         } else if (state == IP_VS_STATE_BACKUP) {
1901                 if (!ipvs->backup_threads)
1902                         return -ESRCH;
1903
1904                 ipvs->sync_state &= ~IP_VS_STATE_BACKUP;
1905                 array = ipvs->backup_threads;
1906                 retc = 0;
1907                 for (id = ipvs->threads_mask; id >= 0; id--) {
1908                         int ret;
1909
1910                         pr_info("stopping backup sync thread %d ...\n",
1911                                 task_pid_nr(array[id]));
1912                         ret = kthread_stop(array[id]);
1913                         if (retc >= 0)
1914                                 retc = ret;
1915                 }
1916                 kfree(array);
1917                 ipvs->backup_threads = NULL;
1918         }
1919
1920         /* decrease the module use count */
1921         ip_vs_use_count_dec();
1922
1923         return retc;
1924 }
1925
1926 /*
1927  * Initialize data struct for each netns
1928  */
1929 int __net_init ip_vs_sync_net_init(struct net *net)
1930 {
1931         struct netns_ipvs *ipvs = net_ipvs(net);
1932
1933         __mutex_init(&ipvs->sync_mutex, "ipvs->sync_mutex", &__ipvs_sync_key);
1934         spin_lock_init(&ipvs->sync_lock);
1935         spin_lock_init(&ipvs->sync_buff_lock);
1936         return 0;
1937 }
1938
1939 void ip_vs_sync_net_cleanup(struct net *net)
1940 {
1941         int retc;
1942         struct netns_ipvs *ipvs = net_ipvs(net);
1943
1944         mutex_lock(&ipvs->sync_mutex);
1945         retc = stop_sync_thread(net, IP_VS_STATE_MASTER);
1946         if (retc && retc != -ESRCH)
1947                 pr_err("Failed to stop Master Daemon\n");
1948
1949         retc = stop_sync_thread(net, IP_VS_STATE_BACKUP);
1950         if (retc && retc != -ESRCH)
1951                 pr_err("Failed to stop Backup Daemon\n");
1952         mutex_unlock(&ipvs->sync_mutex);
1953 }