net/netfilter/ipvs/ip_vs_sync.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * IPVS         An implementation of the IP virtual server support for the
   4  *              LINUX operating system.  IPVS is now implemented as a module
   5  *              over the NetFilter framework. IPVS can be used to build a
   6  *              high-performance and highly available server based on a
   7  *              cluster of servers.
   8  *
   9  * Version 1,   is capable of handling both version 0 and 1 messages.
  10  *              Version 0 is the plain old format.
  11  *              Note Version 0 receivers will just drop Ver 1 messages.
  12  *              Version 1 is capable of handle IPv6, Persistence data,
  13  *              time-outs, and firewall marks.
  14  *              In ver.1 "ip_vs_sync_conn_options" will be sent in netw. order.
  15  *              Ver. 0 can be turned on by sysctl -w net.ipv4.vs.sync_version=0
  16  *
  17  * Definitions  Message: is a complete datagram
  18  *              Sync_conn: is a part of a Message
  19  *              Param Data is an option to a Sync_conn.
  20  *
  21  * Authors:     Wensong Zhang <wensong@linuxvirtualserver.org>
  22  *
  23  * ip_vs_sync:  sync connection info from master load balancer to backups
  24  *              through multicast
  25  *
  26  * Changes:
  27  *      Alexandre Cassen        :       Added master & backup support at a time.
  28  *      Alexandre Cassen        :       Added SyncID support for incoming sync
  29  *                                      messages filtering.
  30  *      Justin Ossevoort        :       Fix endian problem on sync message size.
  31  *      Hans Schillstrom        :       Added Version 1: i.e. IPv6,
  32  *                                      Persistence support, fwmark and time-out.
  33  */
  34
  35 #define KMSG_COMPONENT "IPVS"
  36 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  37
  38 #include <linux/module.h>
  39 #include <linux/slab.h>
  40 #include <linux/inetdevice.h>
  41 #include <linux/net.h>
  42 #include <linux/completion.h>
  43 #include <linux/delay.h>
  44 #include <linux/skbuff.h>
  45 #include <linux/in.h>
  46 #include <linux/igmp.h>                 /* for ip_mc_join_group */
  47 #include <linux/udp.h>
  48 #include <linux/err.h>
  49 #include <linux/kthread.h>
  50 #include <linux/wait.h>
  51 #include <linux/kernel.h>
  52 #include <linux/sched/signal.h>
  53
  54 #include <asm/unaligned.h>              /* Used for ntoh_seq and hton_seq */
  55
  56 #include <net/ip.h>
  57 #include <net/sock.h>
  58
  59 #include <net/ip_vs.h>
  60
  61 #define IP_VS_SYNC_GROUP 0xe0000051    /* multicast addr - 224.0.0.81 */
  62 #define IP_VS_SYNC_PORT  8848          /* multicast port */
  63
  64 #define SYNC_PROTO_VER  1               /* Protocol version in header */
  65
  66 static struct lock_class_key __ipvs_sync_key;
  67 /*
  68  *      IPVS sync connection entry
  69  *      Version 0, i.e. original version.
  70  */
  71 struct ip_vs_sync_conn_v0 {
  72         __u8                    reserved;
  73
  74         /* Protocol, addresses and port numbers */
  75         __u8                    protocol;       /* Which protocol (TCP/UDP) */
  76         __be16                  cport;
  77         __be16                  vport;
  78         __be16                  dport;
  79         __be32                  caddr;          /* client address */
  80         __be32                  vaddr;          /* virtual address */
  81         __be32                  daddr;          /* destination address */
  82
  83         /* Flags and state transition */
  84         __be16                  flags;          /* status flags */
  85         __be16                  state;          /* state info */
  86
  87         /* The sequence options start here */
  88 };
  89
  90 struct ip_vs_sync_conn_options {
  91         struct ip_vs_seq        in_seq;         /* incoming seq. struct */
  92         struct ip_vs_seq        out_seq;        /* outgoing seq. struct */
  93 };
  94
  95 /*
  96      Sync Connection format (sync_conn)
  97
  98        0                   1                   2                   3
  99        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
 100       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 101       |    Type       |    Protocol   | Ver.  |        Size           |
 102       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 103       |                             Flags                             |
 104       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 105       |            State              |         cport                 |
 106       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 107       |            vport              |         dport                 |
 108       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 109       |                             fwmark                            |
 110       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 111       |                             timeout  (in sec.)                |
 112       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 113       |                              ...                              |
 114       |                        IP-Addresses  (v4 or v6)               |
 115       |                              ...                              |
 116       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 117   Optional Parameters.
 118       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 119       | Param. Type    | Param. Length |   Param. data                |
 120       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               |
 121       |                              ...                              |
 122       |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 123       |                               | Param Type    | Param. Length |
 124       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 125       |                           Param  data                         |
 126       |         Last Param data should be padded for 32 bit alignment |
 127       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 128 */
 129
 130 /*
 131  *  Type 0, IPv4 sync connection format
 132  */
 133 struct ip_vs_sync_v4 {
 134         __u8                    type;
 135         __u8                    protocol;       /* Which protocol (TCP/UDP) */
 136         __be16                  ver_size;       /* Version msb 4 bits */
 137         /* Flags and state transition */
 138         __be32                  flags;          /* status flags */
 139         __be16                  state;          /* state info   */
 140         /* Protocol, addresses and port numbers */
 141         __be16                  cport;
 142         __be16                  vport;
 143         __be16                  dport;
 144         __be32                  fwmark;         /* Firewall mark from skb */
 145         __be32                  timeout;        /* cp timeout */
 146         __be32                  caddr;          /* client address */
 147         __be32                  vaddr;          /* virtual address */
 148         __be32                  daddr;          /* destination address */
 149         /* The sequence options start here */
 150         /* PE data padded to 32bit alignment after seq. options */
 151 };
 152 /*
 153  * Type 2 messages IPv6
 154  */
 155 struct ip_vs_sync_v6 {
 156         __u8                    type;
 157         __u8                    protocol;       /* Which protocol (TCP/UDP) */
 158         __be16                  ver_size;       /* Version msb 4 bits */
 159         /* Flags and state transition */
 160         __be32                  flags;          /* status flags */
 161         __be16                  state;          /* state info   */
 162         /* Protocol, addresses and port numbers */
 163         __be16                  cport;
 164         __be16                  vport;
 165         __be16                  dport;
 166         __be32                  fwmark;         /* Firewall mark from skb */
 167         __be32                  timeout;        /* cp timeout */
 168         struct in6_addr         caddr;          /* client address */
 169         struct in6_addr         vaddr;          /* virtual address */
 170         struct in6_addr         daddr;          /* destination address */
 171         /* The sequence options start here */
 172         /* PE data padded to 32bit alignment after seq. options */
 173 };
 174
 175 union ip_vs_sync_conn {
 176         struct ip_vs_sync_v4    v4;
 177         struct ip_vs_sync_v6    v6;
 178 };
 179
 180 /* Bits in Type field in above */
 181 #define STYPE_INET6             0
 182 #define STYPE_F_INET6           (1 << STYPE_INET6)
 183
 184 #define SVER_SHIFT              12              /* Shift to get version */
 185 #define SVER_MASK               0x0fff          /* Mask to strip version */
 186
 187 #define IPVS_OPT_SEQ_DATA       1
 188 #define IPVS_OPT_PE_DATA        2
 189 #define IPVS_OPT_PE_NAME        3
 190 #define IPVS_OPT_PARAM          7
 191
 192 #define IPVS_OPT_F_SEQ_DATA     (1 << (IPVS_OPT_SEQ_DATA-1))
 193 #define IPVS_OPT_F_PE_DATA      (1 << (IPVS_OPT_PE_DATA-1))
 194 #define IPVS_OPT_F_PE_NAME      (1 << (IPVS_OPT_PE_NAME-1))
 195 #define IPVS_OPT_F_PARAM        (1 << (IPVS_OPT_PARAM-1))
 196
 197 struct ip_vs_sync_thread_data {
 198         struct task_struct *task;
 199         struct netns_ipvs *ipvs;
 200         struct socket *sock;
 201         char *buf;
 202         int id;
 203 };
 204
 205 /* Version 0 definition of packet sizes */
 206 #define SIMPLE_CONN_SIZE  (sizeof(struct ip_vs_sync_conn_v0))
 207 #define FULL_CONN_SIZE  \
 208 (sizeof(struct ip_vs_sync_conn_v0) + sizeof(struct ip_vs_sync_conn_options))
 209
 210
 211 /*
 212   The master mulitcasts messages (Datagrams) to the backup load balancers
 213   in the following format.
 214
 215  Version 1:
 216   Note, first byte should be Zero, so ver 0 receivers will drop the packet.
 217
 218        0                   1                   2                   3
 219        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
 220       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 221       |      0        |    SyncID     |            Size               |
 222       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 223       |  Count Conns  |    Version    |    Reserved, set to Zero      |
 224       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 225       |                                                               |
 226       |                    IPVS Sync Connection (1)                   |
 227       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 228       |                            .                                  |
 229       ~                            .                                  ~
 230       |                            .                                  |
 231       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 232       |                                                               |
 233       |                    IPVS Sync Connection (n)                   |
 234       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 235
 236  Version 0 Header
 237        0                   1                   2                   3
 238        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
 239       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 240       |  Count Conns  |    SyncID     |            Size               |
 241       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 242       |                    IPVS Sync Connection (1)                   |
 243 */
 244
 245 #define SYNC_MESG_HEADER_LEN    4
 246 #define MAX_CONNS_PER_SYNCBUFF  255 /* nr_conns in ip_vs_sync_mesg is 8 bit */
 247
 248 /* Version 0 header */
 249 struct ip_vs_sync_mesg_v0 {
 250         __u8                    nr_conns;
 251         __u8                    syncid;
 252         __be16                  size;
 253
 254         /* ip_vs_sync_conn entries start here */
 255 };
 256
 257 /* Version 1 header */
 258 struct ip_vs_sync_mesg {
 259         __u8                    reserved;       /* must be zero */
 260         __u8                    syncid;
 261         __be16                  size;
 262         __u8                    nr_conns;
 263         __s8                    version;        /* SYNC_PROTO_VER  */
 264         __u16                   spare;
 265         /* ip_vs_sync_conn entries start here */
 266 };
 267
 268 union ipvs_sockaddr {
 269         struct sockaddr_in      in;
 270         struct sockaddr_in6     in6;
 271 };
 272
 273 struct ip_vs_sync_buff {
 274         struct list_head        list;
 275         unsigned long           firstuse;
 276
 277         /* pointers for the message data */
 278         struct ip_vs_sync_mesg  *mesg;
 279         unsigned char           *head;
 280         unsigned char           *end;
 281 };
 282
 283 /*
 284  * Copy of struct ip_vs_seq
 285  * From unaligned network order to aligned host order
 286  */
 287 static void ntoh_seq(struct ip_vs_seq *no, struct ip_vs_seq *ho)
 288 {
 289         memset(ho, 0, sizeof(*ho));
 290         ho->init_seq       = get_unaligned_be32(&no->init_seq);
 291         ho->delta          = get_unaligned_be32(&no->delta);
 292         ho->previous_delta = get_unaligned_be32(&no->previous_delta);
 293 }
 294
 295 /*
 296  * Copy of struct ip_vs_seq
 297  * From Aligned host order to unaligned network order
 298  */
 299 static void hton_seq(struct ip_vs_seq *ho, struct ip_vs_seq *no)
 300 {
 301         put_unaligned_be32(ho->init_seq, &no->init_seq);
 302         put_unaligned_be32(ho->delta, &no->delta);
 303         put_unaligned_be32(ho->previous_delta, &no->previous_delta);
 304 }
 305
 306 static inline struct ip_vs_sync_buff *
 307 sb_dequeue(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
 308 {
 309         struct ip_vs_sync_buff *sb;
 310
 311         spin_lock_bh(&ipvs->sync_lock);
 312         if (list_empty(&ms->sync_queue)) {
 313                 sb = NULL;
 314                 __set_current_state(TASK_INTERRUPTIBLE);
 315         } else {
 316                 sb = list_entry(ms->sync_queue.next, struct ip_vs_sync_buff,
 317                                 list);
 318                 list_del(&sb->list);
 319                 ms->sync_queue_len--;
 320                 if (!ms->sync_queue_len)
 321                         ms->sync_queue_delay = 0;
 322         }
 323         spin_unlock_bh(&ipvs->sync_lock);
 324
 325         return sb;
 326 }
 327
 328 /*
 329  * Create a new sync buffer for Version 1 proto.
 330  */
 331 static inline struct ip_vs_sync_buff *
 332 ip_vs_sync_buff_create(struct netns_ipvs *ipvs, unsigned int len)
 333 {
 334         struct ip_vs_sync_buff *sb;
 335
 336         if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
 337                 return NULL;
 338
 339         len = max_t(unsigned int, len + sizeof(struct ip_vs_sync_mesg),
 340                     ipvs->mcfg.sync_maxlen);
 341         sb->mesg = kmalloc(len, GFP_ATOMIC);
 342         if (!sb->mesg) {
 343                 kfree(sb);
 344                 return NULL;
 345         }
 346         sb->mesg->reserved = 0;  /* old nr_conns i.e. must be zero now */
 347         sb->mesg->version = SYNC_PROTO_VER;
 348         sb->mesg->syncid = ipvs->mcfg.syncid;
 349         sb->mesg->size = htons(sizeof(struct ip_vs_sync_mesg));
 350         sb->mesg->nr_conns = 0;
 351         sb->mesg->spare = 0;
 352         sb->head = (unsigned char *)sb->mesg + sizeof(struct ip_vs_sync_mesg);
 353         sb->end = (unsigned char *)sb->mesg + len;
 354
 355         sb->firstuse = jiffies;
 356         return sb;
 357 }
 358
 359 static inline void ip_vs_sync_buff_release(struct ip_vs_sync_buff *sb)
 360 {
 361         kfree(sb->mesg);
 362         kfree(sb);
 363 }
 364
 365 static inline void sb_queue_tail(struct netns_ipvs *ipvs,
 366                                  struct ipvs_master_sync_state *ms)
 367 {
 368         struct ip_vs_sync_buff *sb = ms->sync_buff;
 369
 370         spin_lock(&ipvs->sync_lock);
 371         if (ipvs->sync_state & IP_VS_STATE_MASTER &&
 372             ms->sync_queue_len < sysctl_sync_qlen_max(ipvs)) {
 373                 if (!ms->sync_queue_len)
 374                         schedule_delayed_work(&ms->master_wakeup_work,
 375                                               max(IPVS_SYNC_SEND_DELAY, 1));
 376                 ms->sync_queue_len++;
 377                 list_add_tail(&sb->list, &ms->sync_queue);
 378                 if ((++ms->sync_queue_delay) == IPVS_SYNC_WAKEUP_RATE) {
 379                         int id = (int)(ms - ipvs->ms);
 380
 381                         wake_up_process(ipvs->master_tinfo[id].task);
 382                 }
 383         } else
 384                 ip_vs_sync_buff_release(sb);
 385         spin_unlock(&ipvs->sync_lock);
 386 }
 387
 388 /*
 389  *      Get the current sync buffer if it has been created for more
 390  *      than the specified time or the specified time is zero.
 391  */
 392 static inline struct ip_vs_sync_buff *
 393 get_curr_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms,
 394                    unsigned long time)
 395 {
 396         struct ip_vs_sync_buff *sb;
 397
 398         spin_lock_bh(&ipvs->sync_buff_lock);
 399         sb = ms->sync_buff;
 400         if (sb && time_after_eq(jiffies - sb->firstuse, time)) {
 401                 ms->sync_buff = NULL;
 402                 __set_current_state(TASK_RUNNING);
 403         } else
 404                 sb = NULL;
 405         spin_unlock_bh(&ipvs->sync_buff_lock);
 406         return sb;
 407 }
 408
 409 static inline int
 410 select_master_thread_id(struct netns_ipvs *ipvs, struct ip_vs_conn *cp)
 411 {
 412         return ((long) cp >> (1 + ilog2(sizeof(*cp)))) & ipvs->threads_mask;
 413 }
 414
 415 /*
 416  * Create a new sync buffer for Version 0 proto.
 417  */
 418 static inline struct ip_vs_sync_buff *
 419 ip_vs_sync_buff_create_v0(struct netns_ipvs *ipvs, unsigned int len)
 420 {
 421         struct ip_vs_sync_buff *sb;
 422         struct ip_vs_sync_mesg_v0 *mesg;
 423
 424         if (!(sb=kmalloc(sizeof(struct ip_vs_sync_buff), GFP_ATOMIC)))
 425                 return NULL;
 426
 427         len = max_t(unsigned int, len + sizeof(struct ip_vs_sync_mesg_v0),
 428                     ipvs->mcfg.sync_maxlen);
 429         sb->mesg = kmalloc(len, GFP_ATOMIC);
 430         if (!sb->mesg) {
 431                 kfree(sb);
 432                 return NULL;
 433         }
 434         mesg = (struct ip_vs_sync_mesg_v0 *)sb->mesg;
 435         mesg->nr_conns = 0;
 436         mesg->syncid = ipvs->mcfg.syncid;
 437         mesg->size = htons(sizeof(struct ip_vs_sync_mesg_v0));
 438         sb->head = (unsigned char *)mesg + sizeof(struct ip_vs_sync_mesg_v0);
 439         sb->end = (unsigned char *)mesg + len;
 440         sb->firstuse = jiffies;
 441         return sb;
 442 }
 443
 444 /* Check if connection is controlled by persistence */
 445 static inline bool in_persistence(struct ip_vs_conn *cp)
 446 {
 447         for (cp = cp->control; cp; cp = cp->control) {
 448                 if (cp->flags & IP_VS_CONN_F_TEMPLATE)
 449                         return true;
 450         }
 451         return false;
 452 }
 453
 454 /* Check if conn should be synced.
 455  * pkts: conn packets, use sysctl_sync_threshold to avoid packet check
 456  * - (1) sync_refresh_period: reduce sync rate. Additionally, retry
 457  *      sync_retries times with period of sync_refresh_period/8
 458  * - (2) if both sync_refresh_period and sync_period are 0 send sync only
 459  *      for state changes or only once when pkts matches sync_threshold
 460  * - (3) templates: rate can be reduced only with sync_refresh_period or
 461  *      with (2)
 462  */
 463 static int ip_vs_sync_conn_needed(struct netns_ipvs *ipvs,
 464                                   struct ip_vs_conn *cp, int pkts)
 465 {
 466         unsigned long orig = READ_ONCE(cp->sync_endtime);
 467         unsigned long now = jiffies;
 468         unsigned long n = (now + cp->timeout) & ~3UL;
 469         unsigned int sync_refresh_period;
 470         int sync_period;
 471         int force;
 472
 473         /* Check if we sync in current state */
 474         if (unlikely(cp->flags & IP_VS_CONN_F_TEMPLATE))
 475                 force = 0;
 476         else if (unlikely(sysctl_sync_persist_mode(ipvs) && in_persistence(cp)))
 477                 return 0;
 478         else if (likely(cp->protocol == IPPROTO_TCP)) {
 479                 if (!((1 << cp->state) &
 480                       ((1 << IP_VS_TCP_S_ESTABLISHED) |
 481                        (1 << IP_VS_TCP_S_FIN_WAIT) |
 482                        (1 << IP_VS_TCP_S_CLOSE) |
 483                        (1 << IP_VS_TCP_S_CLOSE_WAIT) |
 484                        (1 << IP_VS_TCP_S_TIME_WAIT))))
 485                         return 0;
 486                 force = cp->state != cp->old_state;
 487                 if (force && cp->state != IP_VS_TCP_S_ESTABLISHED)
 488                         goto set;
 489         } else if (unlikely(cp->protocol == IPPROTO_SCTP)) {
 490                 if (!((1 << cp->state) &
 491                       ((1 << IP_VS_SCTP_S_ESTABLISHED) |
 492                        (1 << IP_VS_SCTP_S_SHUTDOWN_SENT) |
 493                        (1 << IP_VS_SCTP_S_SHUTDOWN_RECEIVED) |
 494                        (1 << IP_VS_SCTP_S_SHUTDOWN_ACK_SENT) |
 495                        (1 << IP_VS_SCTP_S_CLOSED))))
 496                         return 0;
 497                 force = cp->state != cp->old_state;
 498                 if (force && cp->state != IP_VS_SCTP_S_ESTABLISHED)
 499                         goto set;
 500         } else {
 501                 /* UDP or another protocol with single state */
 502                 force = 0;
 503         }
 504
 505         sync_refresh_period = sysctl_sync_refresh_period(ipvs);
 506         if (sync_refresh_period > 0) {
 507                 long diff = n - orig;
 508                 long min_diff = max(cp->timeout >> 1, 10UL * HZ);
 509
 510                 /* Avoid sync if difference is below sync_refresh_period
 511                  * and below the half timeout.
 512                  */
 513                 if (abs(diff) < min_t(long, sync_refresh_period, min_diff)) {
 514                         int retries = orig & 3;
 515
 516                         if (retries >= sysctl_sync_retries(ipvs))
 517                                 return 0;
 518                         if (time_before(now, orig - cp->timeout +
 519                                         (sync_refresh_period >> 3)))
 520                                 return 0;
 521                         n |= retries + 1;
 522                 }
 523         }
 524         sync_period = sysctl_sync_period(ipvs);
 525         if (sync_period > 0) {
 526                 if (!(cp->flags & IP_VS_CONN_F_TEMPLATE) &&
 527                     pkts % sync_period != sysctl_sync_threshold(ipvs))
 528                         return 0;
 529         } else if (!sync_refresh_period &&
 530                    pkts != sysctl_sync_threshold(ipvs))
 531                 return 0;
 532
 533 set:
 534         cp->old_state = cp->state;
 535         n = cmpxchg(&cp->sync_endtime, orig, n);
 536         return n == orig || force;
 537 }
 538
 539 /*
 540  *      Version 0 , could be switched in by sys_ctl.
 541  *      Add an ip_vs_conn information into the current sync_buff.
 542  */
 543 static void ip_vs_sync_conn_v0(struct netns_ipvs *ipvs, struct ip_vs_conn *cp,
 544                                int pkts)
 545 {
 546         struct ip_vs_sync_mesg_v0 *m;
 547         struct ip_vs_sync_conn_v0 *s;
 548         struct ip_vs_sync_buff *buff;
 549         struct ipvs_master_sync_state *ms;
 550         int id;
 551         unsigned int len;
 552
 553         if (unlikely(cp->af != AF_INET))
 554                 return;
 555         /* Do not sync ONE PACKET */
 556         if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
 557                 return;
 558
 559         if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
 560                 return;
 561
 562         spin_lock_bh(&ipvs->sync_buff_lock);
 563         if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
 564                 spin_unlock_bh(&ipvs->sync_buff_lock);
 565                 return;
 566         }
 567
 568         id = select_master_thread_id(ipvs, cp);
 569         ms = &ipvs->ms[id];
 570         buff = ms->sync_buff;
 571         len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE :
 572                 SIMPLE_CONN_SIZE;
 573         if (buff) {
 574                 m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
 575                 /* Send buffer if it is for v1 */
 576                 if (buff->head + len > buff->end || !m->nr_conns) {
 577                         sb_queue_tail(ipvs, ms);
 578                         ms->sync_buff = NULL;
 579                         buff = NULL;
 580                 }
 581         }
 582         if (!buff) {
 583                 buff = ip_vs_sync_buff_create_v0(ipvs, len);
 584                 if (!buff) {
 585                         spin_unlock_bh(&ipvs->sync_buff_lock);
 586                         pr_err("ip_vs_sync_buff_create failed.\n");
 587                         return;
 588                 }
 589                 ms->sync_buff = buff;
 590         }
 591
 592         m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
 593         s = (struct ip_vs_sync_conn_v0 *) buff->head;
 594
 595         /* copy members */
 596         s->reserved = 0;
 597         s->protocol = cp->protocol;
 598         s->cport = cp->cport;
 599         s->vport = cp->vport;
 600         s->dport = cp->dport;
 601         s->caddr = cp->caddr.ip;
 602         s->vaddr = cp->vaddr.ip;
 603         s->daddr = cp->daddr.ip;
 604         s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED);
 605         s->state = htons(cp->state);
 606         if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
 607                 struct ip_vs_sync_conn_options *opt =
 608                         (struct ip_vs_sync_conn_options *)&s[1];
 609                 memcpy(opt, &cp->in_seq, sizeof(*opt));
 610         }
 611
 612         m->nr_conns++;
 613         m->size = htons(ntohs(m->size) + len);
 614         buff->head += len;
 615         spin_unlock_bh(&ipvs->sync_buff_lock);
 616
 617         /* synchronize its controller if it has */
 618         cp = cp->control;
 619         if (cp) {
 620                 if (cp->flags & IP_VS_CONN_F_TEMPLATE)
 621                         pkts = atomic_add_return(1, &cp->in_pkts);
 622                 else
 623                         pkts = sysctl_sync_threshold(ipvs);
 624                 ip_vs_sync_conn(ipvs, cp, pkts);
 625         }
 626 }
 627
 628 /*
 629  *      Add an ip_vs_conn information into the current sync_buff.
 630  *      Called by ip_vs_in.
 631  *      Sending Version 1 messages
 632  */
 633 void ip_vs_sync_conn(struct netns_ipvs *ipvs, struct ip_vs_conn *cp, int pkts)
 634 {
 635         struct ip_vs_sync_mesg *m;
 636         union ip_vs_sync_conn *s;
 637         struct ip_vs_sync_buff *buff;
 638         struct ipvs_master_sync_state *ms;
 639         int id;
 640         __u8 *p;
 641         unsigned int len, pe_name_len, pad;
 642
 643         /* Handle old version of the protocol */
 644         if (sysctl_sync_ver(ipvs) == 0) {
 645                 ip_vs_sync_conn_v0(ipvs, cp, pkts);
 646                 return;
 647         }
 648         /* Do not sync ONE PACKET */
 649         if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
 650                 goto control;
 651 sloop:
 652         if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
 653                 goto control;
 654
 655         /* Sanity checks */
 656         pe_name_len = 0;
 657         if (cp->pe_data_len) {
 658                 if (!cp->pe_data || !cp->dest) {
 659                         IP_VS_ERR_RL("SYNC, connection pe_data invalid\n");
 660                         return;
 661                 }
 662                 pe_name_len = strnlen(cp->pe->name, IP_VS_PENAME_MAXLEN);
 663         }
 664
 665         spin_lock_bh(&ipvs->sync_buff_lock);
 666         if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
 667                 spin_unlock_bh(&ipvs->sync_buff_lock);
 668                 return;
 669         }
 670
 671         id = select_master_thread_id(ipvs, cp);
 672         ms = &ipvs->ms[id];
 673
 674 #ifdef CONFIG_IP_VS_IPV6
 675         if (cp->af == AF_INET6)
 676                 len = sizeof(struct ip_vs_sync_v6);
 677         else
 678 #endif
 679                 len = sizeof(struct ip_vs_sync_v4);
 680
 681         if (cp->flags & IP_VS_CONN_F_SEQ_MASK)
 682                 len += sizeof(struct ip_vs_sync_conn_options) + 2;
 683
 684         if (cp->pe_data_len)
 685                 len += cp->pe_data_len + 2;     /* + Param hdr field */
 686         if (pe_name_len)
 687                 len += pe_name_len + 2;
 688
 689         /* check if there is a space for this one  */
 690         pad = 0;
 691         buff = ms->sync_buff;
 692         if (buff) {
 693                 m = buff->mesg;
 694                 pad = (4 - (size_t) buff->head) & 3;
 695                 /* Send buffer if it is for v0 */
 696                 if (buff->head + len + pad > buff->end || m->reserved) {
 697                         sb_queue_tail(ipvs, ms);
 698                         ms->sync_buff = NULL;
 699                         buff = NULL;
 700                         pad = 0;
 701                 }
 702         }
 703
 704         if (!buff) {
 705                 buff = ip_vs_sync_buff_create(ipvs, len);
 706                 if (!buff) {
 707                         spin_unlock_bh(&ipvs->sync_buff_lock);
 708                         pr_err("ip_vs_sync_buff_create failed.\n");
 709                         return;
 710                 }
 711                 ms->sync_buff = buff;
 712                 m = buff->mesg;
 713         }
 714
 715         p = buff->head;
 716         buff->head += pad + len;
 717         m->size = htons(ntohs(m->size) + pad + len);
 718         /* Add ev. padding from prev. sync_conn */
 719         while (pad--)
 720                 *(p++) = 0;
 721
 722         s = (union ip_vs_sync_conn *)p;
 723
 724         /* Set message type  & copy members */
 725         s->v4.type = (cp->af == AF_INET6 ? STYPE_F_INET6 : 0);
 726         s->v4.ver_size = htons(len & SVER_MASK);        /* Version 0 */
 727         s->v4.flags = htonl(cp->flags & ~IP_VS_CONN_F_HASHED);
 728         s->v4.state = htons(cp->state);
 729         s->v4.protocol = cp->protocol;
 730         s->v4.cport = cp->cport;
 731         s->v4.vport = cp->vport;
 732         s->v4.dport = cp->dport;
 733         s->v4.fwmark = htonl(cp->fwmark);
 734         s->v4.timeout = htonl(cp->timeout / HZ);
 735         m->nr_conns++;
 736
 737 #ifdef CONFIG_IP_VS_IPV6
 738         if (cp->af == AF_INET6) {
 739                 p += sizeof(struct ip_vs_sync_v6);
 740                 s->v6.caddr = cp->caddr.in6;
 741                 s->v6.vaddr = cp->vaddr.in6;
 742                 s->v6.daddr = cp->daddr.in6;
 743         } else
 744 #endif
 745         {
 746                 p += sizeof(struct ip_vs_sync_v4);      /* options ptr */
 747                 s->v4.caddr = cp->caddr.ip;
 748                 s->v4.vaddr = cp->vaddr.ip;
 749                 s->v4.daddr = cp->daddr.ip;
 750         }
 751         if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
 752                 *(p++) = IPVS_OPT_SEQ_DATA;
 753                 *(p++) = sizeof(struct ip_vs_sync_conn_options);
 754                 hton_seq((struct ip_vs_seq *)p, &cp->in_seq);
 755                 p += sizeof(struct ip_vs_seq);
 756                 hton_seq((struct ip_vs_seq *)p, &cp->out_seq);
 757                 p += sizeof(struct ip_vs_seq);
 758         }
 759         /* Handle pe data */
 760         if (cp->pe_data_len && cp->pe_data) {
 761                 *(p++) = IPVS_OPT_PE_DATA;
 762                 *(p++) = cp->pe_data_len;
 763                 memcpy(p, cp->pe_data, cp->pe_data_len);
 764                 p += cp->pe_data_len;
 765                 if (pe_name_len) {
 766                         /* Add PE_NAME */
 767                         *(p++) = IPVS_OPT_PE_NAME;
 768                         *(p++) = pe_name_len;
 769                         memcpy(p, cp->pe->name, pe_name_len);
 770                         p += pe_name_len;
 771                 }
 772         }
 773
 774         spin_unlock_bh(&ipvs->sync_buff_lock);
 775
 776 control:
 777         /* synchronize its controller if it has */
 778         cp = cp->control;
 779         if (!cp)
 780                 return;
 781         if (cp->flags & IP_VS_CONN_F_TEMPLATE)
 782                 pkts = atomic_add_return(1, &cp->in_pkts);
 783         else
 784                 pkts = sysctl_sync_threshold(ipvs);
 785         goto sloop;
 786 }
 787
 788 /*
 789  *  fill_param used by version 1
 790  */
 791 static inline int
 792 ip_vs_conn_fill_param_sync(struct netns_ipvs *ipvs, int af, union ip_vs_sync_conn *sc,
 793                            struct ip_vs_conn_param *p,
 794                            __u8 *pe_data, unsigned int pe_data_len,
 795                            __u8 *pe_name, unsigned int pe_name_len)
 796 {
 797 #ifdef CONFIG_IP_VS_IPV6
 798         if (af == AF_INET6)
 799                 ip_vs_conn_fill_param(ipvs, af, sc->v6.protocol,
 800                                       (const union nf_inet_addr *)&sc->v6.caddr,
 801                                       sc->v6.cport,
 802                                       (const union nf_inet_addr *)&sc->v6.vaddr,
 803                                       sc->v6.vport, p);
 804         else
 805 #endif
 806                 ip_vs_conn_fill_param(ipvs, af, sc->v4.protocol,
 807                                       (const union nf_inet_addr *)&sc->v4.caddr,
 808                                       sc->v4.cport,
 809                                       (const union nf_inet_addr *)&sc->v4.vaddr,
 810                                       sc->v4.vport, p);
 811         /* Handle pe data */
 812         if (pe_data_len) {
 813                 if (pe_name_len) {
 814                         char buff[IP_VS_PENAME_MAXLEN+1];
 815
 816                         memcpy(buff, pe_name, pe_name_len);
 817                         buff[pe_name_len]=0;
 818                         p->pe = __ip_vs_pe_getbyname(buff);
 819                         if (!p->pe) {
 820                                 IP_VS_DBG(3, "BACKUP, no %s engine found/loaded\n",
 821                                              buff);
 822                                 return 1;
 823                         }
 824                 } else {
 825                         IP_VS_ERR_RL("BACKUP, Invalid PE parameters\n");
 826                         return 1;
 827                 }
 828
 829                 p->pe_data = kmemdup(pe_data, pe_data_len, GFP_ATOMIC);
 830                 if (!p->pe_data) {
 831                         module_put(p->pe->module);
 832                         return -ENOMEM;
 833                 }
 834                 p->pe_data_len = pe_data_len;
 835         }
 836         return 0;
 837 }
 838
 839 /*
 840  *  Connection Add / Update.
 841  *  Common for version 0 and 1 reception of backup sync_conns.
 842  *  Param: ...
 843  *         timeout is in sec.
 844  */
 845 static void ip_vs_proc_conn(struct netns_ipvs *ipvs, struct ip_vs_conn_param *param,
 846                             unsigned int flags, unsigned int state,
 847                             unsigned int protocol, unsigned int type,
 848                             const union nf_inet_addr *daddr, __be16 dport,
 849                             unsigned long timeout, __u32 fwmark,
 850                             struct ip_vs_sync_conn_options *opt)
 851 {
 852         struct ip_vs_dest *dest;
 853         struct ip_vs_conn *cp;
 854
 855         if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
 856                 cp = ip_vs_conn_in_get(param);
 857                 if (cp && ((cp->dport != dport) ||
 858                            !ip_vs_addr_equal(cp->daf, &cp->daddr, daddr))) {
 859                         if (!(flags & IP_VS_CONN_F_INACTIVE)) {
 860                                 ip_vs_conn_expire_now(cp);
 861                                 __ip_vs_conn_put(cp);
 862                                 cp = NULL;
 863                         } else {
 864                                 /* This is the expiration message for the
 865                                  * connection that was already replaced, so we
 866                                  * just ignore it.
 867                                  */
 868                                 __ip_vs_conn_put(cp);
 869                                 kfree(param->pe_data);
 870                                 return;
 871                         }
 872                 }
 873         } else {
 874                 cp = ip_vs_ct_in_get(param);
 875         }
 876
 877         if (cp) {
 878                 /* Free pe_data */
 879                 kfree(param->pe_data);
 880
 881                 dest = cp->dest;
 882                 spin_lock_bh(&cp->lock);
 883                 if ((cp->flags ^ flags) & IP_VS_CONN_F_INACTIVE &&
 884                     !(flags & IP_VS_CONN_F_TEMPLATE) && dest) {
 885                         if (flags & IP_VS_CONN_F_INACTIVE) {
 886                                 atomic_dec(&dest->activeconns);
 887                                 atomic_inc(&dest->inactconns);
 888                         } else {
 889                                 atomic_inc(&dest->activeconns);
 890                                 atomic_dec(&dest->inactconns);
 891                         }
 892                 }
 893                 flags &= IP_VS_CONN_F_BACKUP_UPD_MASK;
 894                 flags |= cp->flags & ~IP_VS_CONN_F_BACKUP_UPD_MASK;
 895                 cp->flags = flags;
 896                 spin_unlock_bh(&cp->lock);
 897                 if (!dest)
 898                         ip_vs_try_bind_dest(cp);
 899         } else {
 900                 /*
 901                  * Find the appropriate destination for the connection.
 902                  * If it is not found the connection will remain unbound
 903                  * but still handled.
 904                  */
 905                 rcu_read_lock();
 906                 /* This function is only invoked by the synchronization
 907                  * code. We do not currently support heterogeneous pools
 908                  * with synchronization, so we can make the assumption that
 909                  * the svc_af is the same as the dest_af
 910                  */
 911                 dest = ip_vs_find_dest(ipvs, type, type, daddr, dport,
 912                                        param->vaddr, param->vport, protocol,
 913                                        fwmark, flags);
 914
 915                 cp = ip_vs_conn_new(param, type, daddr, dport, flags, dest,
 916                                     fwmark);
 917                 rcu_read_unlock();
 918                 if (!cp) {
 919                         kfree(param->pe_data);
 920                         IP_VS_DBG(2, "BACKUP, add new conn. failed\n");
 921                         return;
 922                 }
 923                 if (!(flags & IP_VS_CONN_F_TEMPLATE))
 924                         kfree(param->pe_data);
 925         }
 926
 927         if (opt) {
 928                 cp->in_seq = opt->in_seq;
 929                 cp->out_seq = opt->out_seq;
 930         }
 931         atomic_set(&cp->in_pkts, sysctl_sync_threshold(ipvs));
 932         cp->state = state;
 933         cp->old_state = cp->state;
 934         /*
 935          * For Ver 0 messages style
 936          *  - Not possible to recover the right timeout for templates
 937          *  - can not find the right fwmark
 938          *    virtual service. If needed, we can do it for
 939          *    non-fwmark persistent services.
 940          * Ver 1 messages style.
 941          *  - No problem.
 942          */
 943         if (timeout) {
 944                 if (timeout > MAX_SCHEDULE_TIMEOUT / HZ)
 945                         timeout = MAX_SCHEDULE_TIMEOUT / HZ;
 946                 cp->timeout = timeout*HZ;
 947         } else {
 948                 struct ip_vs_proto_data *pd;
 949
 950                 pd = ip_vs_proto_data_get(ipvs, protocol);
 951                 if (!(flags & IP_VS_CONN_F_TEMPLATE) && pd && pd->timeout_table)
 952                         cp->timeout = pd->timeout_table[state];
 953                 else
 954                         cp->timeout = (3*60*HZ);
 955         }
 956         ip_vs_conn_put(cp);
 957 }
 958
 959 /*
 960  *  Process received multicast message for Version 0
 961  */
 962 static void ip_vs_process_message_v0(struct netns_ipvs *ipvs, const char *buffer,
 963                                      const size_t buflen)
 964 {
 965         struct ip_vs_sync_mesg_v0 *m = (struct ip_vs_sync_mesg_v0 *)buffer;
 966         struct ip_vs_sync_conn_v0 *s;
 967         struct ip_vs_sync_conn_options *opt;
 968         struct ip_vs_protocol *pp;
 969         struct ip_vs_conn_param param;
 970         char *p;
 971         int i;
 972
 973         p = (char *)buffer + sizeof(struct ip_vs_sync_mesg_v0);
 974         for (i=0; i<m->nr_conns; i++) {
 975                 unsigned int flags, state;
 976
 977                 if (p + SIMPLE_CONN_SIZE > buffer+buflen) {
 978                         IP_VS_ERR_RL("BACKUP v0, bogus conn\n");
 979                         return;
 980                 }
 981                 s = (struct ip_vs_sync_conn_v0 *) p;
 982                 flags = ntohs(s->flags) | IP_VS_CONN_F_SYNC;
 983                 flags &= ~IP_VS_CONN_F_HASHED;
 984                 if (flags & IP_VS_CONN_F_SEQ_MASK) {
 985                         opt = (struct ip_vs_sync_conn_options *)&s[1];
 986                         p += FULL_CONN_SIZE;
 987                         if (p > buffer+buflen) {
 988                                 IP_VS_ERR_RL("BACKUP v0, Dropping buffer bogus conn options\n");
 989                                 return;
 990                         }
 991                 } else {
 992                         opt = NULL;
 993                         p += SIMPLE_CONN_SIZE;
 994                 }
 995
 996                 state = ntohs(s->state);
 997                 if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
 998                         pp = ip_vs_proto_get(s->protocol);
 999                         if (!pp) {
1000                                 IP_VS_DBG(2, "BACKUP v0, Unsupported protocol %u\n",
1001                                         s->protocol);
1002                                 continue;
1003                         }
1004                         if (state >= pp->num_states) {
1005                                 IP_VS_DBG(2, "BACKUP v0, Invalid %s state %u\n",
1006                                         pp->name, state);
1007                                 continue;
1008                         }
1009                 } else {
1010                         if (state >= IP_VS_CTPL_S_LAST)
1011                                 IP_VS_DBG(7, "BACKUP v0, Invalid tpl state %u\n",
1012                                           state);
1013                 }
1014
1015                 ip_vs_conn_fill_param(ipvs, AF_INET, s->protocol,
1016                                       (const union nf_inet_addr *)&s->caddr,
1017                                       s->cport,
1018                                       (const union nf_inet_addr *)&s->vaddr,
1019                                       s->vport, &param);
1020
1021                 /* Send timeout as Zero */
1022                 ip_vs_proc_conn(ipvs, &param, flags, state, s->protocol, AF_INET,
1023                                 (union nf_inet_addr *)&s->daddr, s->dport,
1024                                 0, 0, opt);
1025         }
1026 }
1027
1028 /*
1029  * Handle options
1030  */
1031 static inline int ip_vs_proc_seqopt(__u8 *p, unsigned int plen,
1032                                     __u32 *opt_flags,
1033                                     struct ip_vs_sync_conn_options *opt)
1034 {
1035         struct ip_vs_sync_conn_options *topt;
1036
1037         topt = (struct ip_vs_sync_conn_options *)p;
1038
1039         if (plen != sizeof(struct ip_vs_sync_conn_options)) {
1040                 IP_VS_DBG(2, "BACKUP, bogus conn options length\n");
1041                 return -EINVAL;
1042         }
1043         if (*opt_flags & IPVS_OPT_F_SEQ_DATA) {
1044                 IP_VS_DBG(2, "BACKUP, conn options found twice\n");
1045                 return -EINVAL;
1046         }
1047         ntoh_seq(&topt->in_seq, &opt->in_seq);
1048         ntoh_seq(&topt->out_seq, &opt->out_seq);
1049         *opt_flags |= IPVS_OPT_F_SEQ_DATA;
1050         return 0;
1051 }
1052
1053 static int ip_vs_proc_str(__u8 *p, unsigned int plen, unsigned int *data_len,
1054                           __u8 **data, unsigned int maxlen,
1055                           __u32 *opt_flags, __u32 flag)
1056 {
1057         if (plen > maxlen) {
1058                 IP_VS_DBG(2, "BACKUP, bogus par.data len > %d\n", maxlen);
1059                 return -EINVAL;
1060         }
1061         if (*opt_flags & flag) {
1062                 IP_VS_DBG(2, "BACKUP, Par.data found twice 0x%x\n", flag);
1063                 return -EINVAL;
1064         }
1065         *data_len = plen;
1066         *data = p;
1067         *opt_flags |= flag;
1068         return 0;
1069 }
1070 /*
1071  *   Process a Version 1 sync. connection
1072  */
1073 static inline int ip_vs_proc_sync_conn(struct netns_ipvs *ipvs, __u8 *p, __u8 *msg_end)
1074 {
1075         struct ip_vs_sync_conn_options opt;
1076         union  ip_vs_sync_conn *s;
1077         struct ip_vs_protocol *pp;
1078         struct ip_vs_conn_param param;
1079         __u32 flags;
1080         unsigned int af, state, pe_data_len=0, pe_name_len=0;
1081         __u8 *pe_data=NULL, *pe_name=NULL;
1082         __u32 opt_flags=0;
1083         int retc=0;
1084
1085         s = (union ip_vs_sync_conn *) p;
1086
1087         if (s->v6.type & STYPE_F_INET6) {
1088 #ifdef CONFIG_IP_VS_IPV6
1089                 af = AF_INET6;
1090                 p += sizeof(struct ip_vs_sync_v6);
1091 #else
1092                 IP_VS_DBG(3,"BACKUP, IPv6 msg received, and IPVS is not compiled for IPv6\n");
1093                 retc = 10;
1094                 goto out;
1095 #endif
1096         } else if (!s->v4.type) {
1097                 af = AF_INET;
1098                 p += sizeof(struct ip_vs_sync_v4);
1099         } else {
1100                 return -10;
1101         }
1102         if (p > msg_end)
1103                 return -20;
1104
1105         /* Process optional params check Type & Len. */
1106         while (p < msg_end) {
1107                 int ptype;
1108                 int plen;
1109
1110                 if (p+2 > msg_end)
1111                         return -30;
1112                 ptype = *(p++);
1113                 plen  = *(p++);
1114
1115                 if (!plen || ((p + plen) > msg_end))
1116                         return -40;
1117                 /* Handle seq option  p = param data */
1118                 switch (ptype & ~IPVS_OPT_F_PARAM) {
1119                 case IPVS_OPT_SEQ_DATA:
1120                         if (ip_vs_proc_seqopt(p, plen, &opt_flags, &opt))
1121                                 return -50;
1122                         break;
1123
1124                 case IPVS_OPT_PE_DATA:
1125                         if (ip_vs_proc_str(p, plen, &pe_data_len, &pe_data,
1126                                            IP_VS_PEDATA_MAXLEN, &opt_flags,
1127                                            IPVS_OPT_F_PE_DATA))
1128                                 return -60;
1129                         break;
1130
1131                 case IPVS_OPT_PE_NAME:
1132                         if (ip_vs_proc_str(p, plen,&pe_name_len, &pe_name,
1133                                            IP_VS_PENAME_MAXLEN, &opt_flags,
1134                                            IPVS_OPT_F_PE_NAME))
1135                                 return -70;
1136                         break;
1137
1138                 default:
1139                         /* Param data mandatory ? */
1140                         if (!(ptype & IPVS_OPT_F_PARAM)) {
1141                                 IP_VS_DBG(3, "BACKUP, Unknown mandatory param %d found\n",
1142                                           ptype & ~IPVS_OPT_F_PARAM);
1143                                 retc = 20;
1144                                 goto out;
1145                         }
1146                 }
1147                 p += plen;  /* Next option */
1148         }
1149
1150         /* Get flags and Mask off unsupported */
1151         flags  = ntohl(s->v4.flags) & IP_VS_CONN_F_BACKUP_MASK;
1152         flags |= IP_VS_CONN_F_SYNC;
1153         state = ntohs(s->v4.state);
1154
1155         if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
1156                 pp = ip_vs_proto_get(s->v4.protocol);
1157                 if (!pp) {
1158                         IP_VS_DBG(3,"BACKUP, Unsupported protocol %u\n",
1159                                 s->v4.protocol);
1160                         retc = 30;
1161                         goto out;
1162                 }
1163                 if (state >= pp->num_states) {
1164                         IP_VS_DBG(3, "BACKUP, Invalid %s state %u\n",
1165                                 pp->name, state);
1166                         retc = 40;
1167                         goto out;
1168                 }
1169         } else {
1170                 if (state >= IP_VS_CTPL_S_LAST)
1171                         IP_VS_DBG(7, "BACKUP, Invalid tpl state %u\n",
1172                                   state);
1173         }
1174         if (ip_vs_conn_fill_param_sync(ipvs, af, s, &param, pe_data,
1175                                        pe_data_len, pe_name, pe_name_len)) {
1176                 retc = 50;
1177                 goto out;
1178         }
1179         /* If only IPv4, just silent skip IPv6 */
1180         if (af == AF_INET)
1181                 ip_vs_proc_conn(ipvs, &param, flags, state, s->v4.protocol, af,
1182                                 (union nf_inet_addr *)&s->v4.daddr, s->v4.dport,
1183                                 ntohl(s->v4.timeout), ntohl(s->v4.fwmark),
1184                                 (opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1185                                 );
1186 #ifdef CONFIG_IP_VS_IPV6
1187         else
1188                 ip_vs_proc_conn(ipvs, &param, flags, state, s->v6.protocol, af,
1189                                 (union nf_inet_addr *)&s->v6.daddr, s->v6.dport,
1190                                 ntohl(s->v6.timeout), ntohl(s->v6.fwmark),
1191                                 (opt_flags & IPVS_OPT_F_SEQ_DATA ? &opt : NULL)
1192                                 );
1193 #endif
1194         ip_vs_pe_put(param.pe);
1195         return 0;
1196         /* Error exit */
1197 out:
1198         IP_VS_DBG(2, "BACKUP, Single msg dropped err:%d\n", retc);
1199         return retc;
1200
1201 }
1202 /*
1203  *      Process received multicast message and create the corresponding
1204  *      ip_vs_conn entries.
1205  *      Handles Version 0 & 1
1206  */
1207 static void ip_vs_process_message(struct netns_ipvs *ipvs, __u8 *buffer,
1208                                   const size_t buflen)
1209 {
1210         struct ip_vs_sync_mesg *m2 = (struct ip_vs_sync_mesg *)buffer;
1211         __u8 *p, *msg_end;
1212         int i, nr_conns;
1213
1214         if (buflen < sizeof(struct ip_vs_sync_mesg_v0)) {
1215                 IP_VS_DBG(2, "BACKUP, message header too short\n");
1216                 return;
1217         }
1218
1219         if (buflen != ntohs(m2->size)) {
1220                 IP_VS_DBG(2, "BACKUP, bogus message size\n");
1221                 return;
1222         }
1223         /* SyncID sanity check */
1224         if (ipvs->bcfg.syncid != 0 && m2->syncid != ipvs->bcfg.syncid) {
1225                 IP_VS_DBG(7, "BACKUP, Ignoring syncid = %d\n", m2->syncid);
1226                 return;
1227         }
1228         /* Handle version 1  message */
1229         if ((m2->version == SYNC_PROTO_VER) && (m2->reserved == 0)
1230             && (m2->spare == 0)) {
1231
1232                 msg_end = buffer + sizeof(struct ip_vs_sync_mesg);
1233                 nr_conns = m2->nr_conns;
1234
1235                 for (i=0; i<nr_conns; i++) {
1236                         union ip_vs_sync_conn *s;
1237                         unsigned int size;
1238                         int retc;
1239
1240                         p = msg_end;
1241                         if (p + sizeof(s->v4) > buffer+buflen) {
1242                                 IP_VS_ERR_RL("BACKUP, Dropping buffer, to small\n");
1243                                 return;
1244                         }
1245                         s = (union ip_vs_sync_conn *)p;
1246                         size = ntohs(s->v4.ver_size) & SVER_MASK;
1247                         msg_end = p + size;
1248                         /* Basic sanity checks */
1249                         if (msg_end  > buffer+buflen) {
1250                                 IP_VS_ERR_RL("BACKUP, Dropping buffer, msg > buffer\n");
1251                                 return;
1252                         }
1253                         if (ntohs(s->v4.ver_size) >> SVER_SHIFT) {
1254                                 IP_VS_ERR_RL("BACKUP, Dropping buffer, Unknown version %d\n",
1255                                               ntohs(s->v4.ver_size) >> SVER_SHIFT);
1256                                 return;
1257                         }
1258                         /* Process a single sync_conn */
1259                         retc = ip_vs_proc_sync_conn(ipvs, p, msg_end);
1260                         if (retc < 0) {
1261                                 IP_VS_ERR_RL("BACKUP, Dropping buffer, Err: %d in decoding\n",
1262                                              retc);
1263                                 return;
1264                         }
1265                         /* Make sure we have 32 bit alignment */
1266                         msg_end = p + ((size + 3) & ~3);
1267                 }
1268         } else {
1269                 /* Old type of message */
1270                 ip_vs_process_message_v0(ipvs, buffer, buflen);
1271                 return;
1272         }
1273 }
1274
1275
1276 /*
1277  *      Setup sndbuf (mode=1) or rcvbuf (mode=0)
1278  */
1279 static void set_sock_size(struct sock *sk, int mode, int val)
1280 {
1281         /* setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)); */
1282         /* setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)); */
1283         lock_sock(sk);
1284         if (mode) {
1285                 val = clamp_t(int, val, (SOCK_MIN_SNDBUF + 1) / 2,
1286                               sysctl_wmem_max);
1287                 sk->sk_sndbuf = val * 2;
1288                 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1289         } else {
1290                 val = clamp_t(int, val, (SOCK_MIN_RCVBUF + 1) / 2,
1291                               sysctl_rmem_max);
1292                 sk->sk_rcvbuf = val * 2;
1293                 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
1294         }
1295         release_sock(sk);
1296 }
1297
1298 /*
1299  *      Setup loopback of outgoing multicasts on a sending socket
1300  */
1301 static void set_mcast_loop(struct sock *sk, u_char loop)
1302 {
1303         struct inet_sock *inet = inet_sk(sk);
1304
1305         /* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */
1306         lock_sock(sk);
1307         inet->mc_loop = loop ? 1 : 0;
1308 #ifdef CONFIG_IP_VS_IPV6
1309         if (sk->sk_family == AF_INET6) {
1310                 struct ipv6_pinfo *np = inet6_sk(sk);
1311
1312                 /* IPV6_MULTICAST_LOOP */
1313                 np->mc_loop = loop ? 1 : 0;
1314         }
1315 #endif
1316         release_sock(sk);
1317 }
1318
1319 /*
1320  *      Specify TTL for outgoing multicasts on a sending socket
1321  */
1322 static void set_mcast_ttl(struct sock *sk, u_char ttl)
1323 {
1324         struct inet_sock *inet = inet_sk(sk);
1325
1326         /* setsockopt(sock, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)); */
1327         lock_sock(sk);
1328         inet->mc_ttl = ttl;
1329 #ifdef CONFIG_IP_VS_IPV6
1330         if (sk->sk_family == AF_INET6) {
1331                 struct ipv6_pinfo *np = inet6_sk(sk);
1332
1333                 /* IPV6_MULTICAST_HOPS */
1334                 np->mcast_hops = ttl;
1335         }
1336 #endif
1337         release_sock(sk);
1338 }
1339
1340 /* Control fragmentation of messages */
1341 static void set_mcast_pmtudisc(struct sock *sk, int val)
1342 {
1343         struct inet_sock *inet = inet_sk(sk);
1344
1345         /* setsockopt(sock, SOL_IP, IP_MTU_DISCOVER, &val, sizeof(val)); */
1346         lock_sock(sk);
1347         inet->pmtudisc = val;
1348 #ifdef CONFIG_IP_VS_IPV6
1349         if (sk->sk_family == AF_INET6) {
1350                 struct ipv6_pinfo *np = inet6_sk(sk);
1351
1352                 /* IPV6_MTU_DISCOVER */
1353                 np->pmtudisc = val;
1354         }
1355 #endif
1356         release_sock(sk);
1357 }
1358
1359 /*
1360  *      Specifiy default interface for outgoing multicasts
1361  */
1362 static int set_mcast_if(struct sock *sk, struct net_device *dev)
1363 {
1364         struct inet_sock *inet = inet_sk(sk);
1365
1366         if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1367                 return -EINVAL;
1368
1369         lock_sock(sk);
1370         inet->mc_index = dev->ifindex;
1371         /*  inet->mc_addr  = 0; */
1372 #ifdef CONFIG_IP_VS_IPV6
1373         if (sk->sk_family == AF_INET6) {
1374                 struct ipv6_pinfo *np = inet6_sk(sk);
1375
1376                 /* IPV6_MULTICAST_IF */
1377                 np->mcast_oif = dev->ifindex;
1378         }
1379 #endif
1380         release_sock(sk);
1381
1382         return 0;
1383 }
1384
1385
1386 /*
1387  *      Join a multicast group.
1388  *      the group is specified by a class D multicast address 224.0.0.0/8
1389  *      in the in_addr structure passed in as a parameter.
1390  */
1391 static int
1392 join_mcast_group(struct sock *sk, struct in_addr *addr, struct net_device *dev)
1393 {
1394         struct ip_mreqn mreq;
1395         int ret;
1396
1397         memset(&mreq, 0, sizeof(mreq));
1398         memcpy(&mreq.imr_multiaddr, addr, sizeof(struct in_addr));
1399
1400         if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1401                 return -EINVAL;
1402
1403         mreq.imr_ifindex = dev->ifindex;
1404
1405         lock_sock(sk);
1406         ret = ip_mc_join_group(sk, &mreq);
1407         release_sock(sk);
1408
1409         return ret;
1410 }
1411
1412 #ifdef CONFIG_IP_VS_IPV6
1413 static int join_mcast_group6(struct sock *sk, struct in6_addr *addr,
1414                              struct net_device *dev)
1415 {
1416         int ret;
1417
1418         if (sk->sk_bound_dev_if && dev->ifindex != sk->sk_bound_dev_if)
1419                 return -EINVAL;
1420
1421         lock_sock(sk);
1422         ret = ipv6_sock_mc_join(sk, dev->ifindex, addr);
1423         release_sock(sk);
1424
1425         return ret;
1426 }
1427 #endif
1428
1429 static int bind_mcastif_addr(struct socket *sock, struct net_device *dev)
1430 {
1431         __be32 addr;
1432         struct sockaddr_in sin;
1433
1434         addr = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
1435         if (!addr)
1436                 pr_err("You probably need to specify IP address on "
1437                        "multicast interface.\n");
1438
1439         IP_VS_DBG(7, "binding socket with (%s) %pI4\n",
1440                   dev->name, &addr);
1441
1442         /* Now bind the socket with the address of multicast interface */
1443         sin.sin_family       = AF_INET;
1444         sin.sin_addr.s_addr  = addr;
1445         sin.sin_port         = 0;
1446
1447         return sock->ops->bind(sock, (struct sockaddr*)&sin, sizeof(sin));
1448 }
1449
1450 static void get_mcast_sockaddr(union ipvs_sockaddr *sa, int *salen,
1451                                struct ipvs_sync_daemon_cfg *c, int id)
1452 {
1453         if (AF_INET6 == c->mcast_af) {
1454                 sa->in6 = (struct sockaddr_in6) {
1455                         .sin6_family = AF_INET6,
1456                         .sin6_port = htons(c->mcast_port + id),
1457                 };
1458                 sa->in6.sin6_addr = c->mcast_group.in6;
1459                 *salen = sizeof(sa->in6);
1460         } else {
1461                 sa->in = (struct sockaddr_in) {
1462                         .sin_family = AF_INET,
1463                         .sin_port = htons(c->mcast_port + id),
1464                 };
1465                 sa->in.sin_addr = c->mcast_group.in;
1466                 *salen = sizeof(sa->in);
1467         }
1468 }
1469
1470 /*
1471  *      Set up sending multicast socket over UDP
1472  */
1473 static int make_send_sock(struct netns_ipvs *ipvs, int id,
1474                           struct net_device *dev, struct socket **sock_ret)
1475 {
1476         /* multicast addr */
1477         union ipvs_sockaddr mcast_addr;
1478         struct socket *sock;
1479         int result, salen;
1480
1481         /* First create a socket */
1482         result = sock_create_kern(ipvs->net, ipvs->mcfg.mcast_af, SOCK_DGRAM,
1483                                   IPPROTO_UDP, &sock);
1484         if (result < 0) {
1485                 pr_err("Error during creation of socket; terminating\n");
1486                 goto error;
1487         }
1488         *sock_ret = sock;
1489         result = set_mcast_if(sock->sk, dev);
1490         if (result < 0) {
1491                 pr_err("Error setting outbound mcast interface\n");
1492                 goto error;
1493         }
1494
1495         set_mcast_loop(sock->sk, 0);
1496         set_mcast_ttl(sock->sk, ipvs->mcfg.mcast_ttl);
1497         /* Allow fragmentation if MTU changes */
1498         set_mcast_pmtudisc(sock->sk, IP_PMTUDISC_DONT);
1499         result = sysctl_sync_sock_size(ipvs);
1500         if (result > 0)
1501                 set_sock_size(sock->sk, 1, result);
1502
1503         if (AF_INET == ipvs->mcfg.mcast_af)
1504                 result = bind_mcastif_addr(sock, dev);
1505         else
1506                 result = 0;
1507         if (result < 0) {
1508                 pr_err("Error binding address of the mcast interface\n");
1509                 goto error;
1510         }
1511
1512         get_mcast_sockaddr(&mcast_addr, &salen, &ipvs->mcfg, id);
1513         result = sock->ops->connect(sock, (struct sockaddr *) &mcast_addr,
1514                                     salen, 0);
1515         if (result < 0) {
1516                 pr_err("Error connecting to the multicast addr\n");
1517                 goto error;
1518         }
1519
1520         return 0;
1521
1522 error:
1523         return result;
1524 }
1525
1526
1527 /*
1528  *      Set up receiving multicast socket over UDP
1529  */
1530 static int make_receive_sock(struct netns_ipvs *ipvs, int id,
1531                              struct net_device *dev, struct socket **sock_ret)
1532 {
1533         /* multicast addr */
1534         union ipvs_sockaddr mcast_addr;
1535         struct socket *sock;
1536         int result, salen;
1537
1538         /* First create a socket */
1539         result = sock_create_kern(ipvs->net, ipvs->bcfg.mcast_af, SOCK_DGRAM,
1540                                   IPPROTO_UDP, &sock);
1541         if (result < 0) {
1542                 pr_err("Error during creation of socket; terminating\n");
1543                 goto error;
1544         }
1545         *sock_ret = sock;
1546         /* it is equivalent to the REUSEADDR option in user-space */
1547         sock->sk->sk_reuse = SK_CAN_REUSE;
1548         result = sysctl_sync_sock_size(ipvs);
1549         if (result > 0)
1550                 set_sock_size(sock->sk, 0, result);
1551
1552         get_mcast_sockaddr(&mcast_addr, &salen, &ipvs->bcfg, id);
1553         sock->sk->sk_bound_dev_if = dev->ifindex;
1554         result = sock->ops->bind(sock, (struct sockaddr *)&mcast_addr, salen);
1555         if (result < 0) {
1556                 pr_err("Error binding to the multicast addr\n");
1557                 goto error;
1558         }
1559
1560         /* join the multicast group */
1561 #ifdef CONFIG_IP_VS_IPV6
1562         if (ipvs->bcfg.mcast_af == AF_INET6)
1563                 result = join_mcast_group6(sock->sk, &mcast_addr.in6.sin6_addr,
1564                                            dev);
1565         else
1566 #endif
1567                 result = join_mcast_group(sock->sk, &mcast_addr.in.sin_addr,
1568                                           dev);
1569         if (result < 0) {
1570                 pr_err("Error joining to the multicast group\n");
1571                 goto error;
1572         }
1573
1574         return 0;
1575
1576 error:
1577         return result;
1578 }
1579
1580
1581 static int
1582 ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length)
1583 {
1584         struct msghdr   msg = {.msg_flags = MSG_DONTWAIT|MSG_NOSIGNAL};
1585         struct kvec     iov;
1586         int             len;
1587
1588         EnterFunction(7);
1589         iov.iov_base     = (void *)buffer;
1590         iov.iov_len      = length;
1591
1592         len = kernel_sendmsg(sock, &msg, &iov, 1, (size_t)(length));
1593
1594         LeaveFunction(7);
1595         return len;
1596 }
1597
1598 static int
1599 ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg)
1600 {
1601         int msize;
1602         int ret;
1603
1604         msize = ntohs(msg->size);
1605
1606         ret = ip_vs_send_async(sock, (char *)msg, msize);
1607         if (ret >= 0 || ret == -EAGAIN)
1608                 return ret;
1609         pr_err("ip_vs_send_async error %d\n", ret);
1610         return 0;
1611 }
1612
1613 static int
1614 ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
1615 {
1616         struct msghdr           msg = {NULL,};
1617         struct kvec             iov = {buffer, buflen};
1618         int                     len;
1619
1620         EnterFunction(7);
1621
1622         /* Receive a packet */
1623         iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, buflen);
1624         len = sock_recvmsg(sock, &msg, MSG_DONTWAIT);
1625         if (len < 0)
1626                 return len;
1627
1628         LeaveFunction(7);
1629         return len;
1630 }
1631
1632 /* Wakeup the master thread for sending */
1633 static void master_wakeup_work_handler(struct work_struct *work)
1634 {
1635         struct ipvs_master_sync_state *ms =
1636                 container_of(work, struct ipvs_master_sync_state,
1637                              master_wakeup_work.work);
1638         struct netns_ipvs *ipvs = ms->ipvs;
1639
1640         spin_lock_bh(&ipvs->sync_lock);
1641         if (ms->sync_queue_len &&
1642             ms->sync_queue_delay < IPVS_SYNC_WAKEUP_RATE) {
1643                 int id = (int)(ms - ipvs->ms);
1644
1645                 ms->sync_queue_delay = IPVS_SYNC_WAKEUP_RATE;
1646                 wake_up_process(ipvs->master_tinfo[id].task);
1647         }
1648         spin_unlock_bh(&ipvs->sync_lock);
1649 }
1650
1651 /* Get next buffer to send */
1652 static inline struct ip_vs_sync_buff *
1653 next_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
1654 {
1655         struct ip_vs_sync_buff *sb;
1656
1657         sb = sb_dequeue(ipvs, ms);
1658         if (sb)
1659                 return sb;
1660         /* Do not delay entries in buffer for more than 2 seconds */
1661         return get_curr_sync_buff(ipvs, ms, IPVS_SYNC_FLUSH_TIME);
1662 }
1663
1664 static int sync_thread_master(void *data)
1665 {
1666         struct ip_vs_sync_thread_data *tinfo = data;
1667         struct netns_ipvs *ipvs = tinfo->ipvs;
1668         struct ipvs_master_sync_state *ms = &ipvs->ms[tinfo->id];
1669         struct sock *sk = tinfo->sock->sk;
1670         struct ip_vs_sync_buff *sb;
1671
1672         pr_info("sync thread started: state = MASTER, mcast_ifn = %s, "
1673                 "syncid = %d, id = %d\n",
1674                 ipvs->mcfg.mcast_ifn, ipvs->mcfg.syncid, tinfo->id);
1675
1676         for (;;) {
1677                 sb = next_sync_buff(ipvs, ms);
1678                 if (unlikely(kthread_should_stop()))
1679                         break;
1680                 if (!sb) {
1681                         schedule_timeout(IPVS_SYNC_CHECK_PERIOD);
1682                         continue;
1683                 }
1684                 while (ip_vs_send_sync_msg(tinfo->sock, sb->mesg) < 0) {
1685                         /* (Ab)use interruptible sleep to avoid increasing
1686                          * the load avg.
1687                          */
1688                         __wait_event_interruptible(*sk_sleep(sk),
1689                                                    sock_writeable(sk) ||
1690                                                    kthread_should_stop());
1691                         if (unlikely(kthread_should_stop()))
1692                                 goto done;
1693                 }
1694                 ip_vs_sync_buff_release(sb);
1695         }
1696
1697 done:
1698         __set_current_state(TASK_RUNNING);
1699         if (sb)
1700                 ip_vs_sync_buff_release(sb);
1701
1702         /* clean up the sync_buff queue */
1703         while ((sb = sb_dequeue(ipvs, ms)))
1704                 ip_vs_sync_buff_release(sb);
1705         __set_current_state(TASK_RUNNING);
1706
1707         /* clean up the current sync_buff */
1708         sb = get_curr_sync_buff(ipvs, ms, 0);
1709         if (sb)
1710                 ip_vs_sync_buff_release(sb);
1711
1712         return 0;
1713 }
1714
1715
1716 static int sync_thread_backup(void *data)
1717 {
1718         struct ip_vs_sync_thread_data *tinfo = data;
1719         struct netns_ipvs *ipvs = tinfo->ipvs;
1720         struct sock *sk = tinfo->sock->sk;
1721         struct udp_sock *up = udp_sk(sk);
1722         int len;
1723
1724         pr_info("sync thread started: state = BACKUP, mcast_ifn = %s, "
1725                 "syncid = %d, id = %d\n",
1726                 ipvs->bcfg.mcast_ifn, ipvs->bcfg.syncid, tinfo->id);
1727
1728         while (!kthread_should_stop()) {
1729                 wait_event_interruptible(*sk_sleep(sk),
1730                                          !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
1731                                          !skb_queue_empty_lockless(&up->reader_queue) ||
1732                                          kthread_should_stop());
1733
1734                 /* do we have data now? */
1735                 while (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
1736                        !skb_queue_empty_lockless(&up->reader_queue)) {
1737                         len = ip_vs_receive(tinfo->sock, tinfo->buf,
1738                                         ipvs->bcfg.sync_maxlen);
1739                         if (len <= 0) {
1740                                 if (len != -EAGAIN)
1741                                         pr_err("receiving message error\n");
1742                                 break;
1743                         }
1744
1745                         ip_vs_process_message(ipvs, tinfo->buf, len);
1746                 }
1747         }
1748
1749         return 0;
1750 }
1751
1752
1753 int start_sync_thread(struct netns_ipvs *ipvs, struct ipvs_sync_daemon_cfg *c,
1754                       int state)
1755 {
1756         struct ip_vs_sync_thread_data *ti = NULL, *tinfo;
1757         struct task_struct *task;
1758         struct net_device *dev;
1759         char *name;
1760         int (*threadfn)(void *data);
1761         int id = 0, count, hlen;
1762         int result = -ENOMEM;
1763         u16 mtu, min_mtu;
1764
1765         IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1766         IP_VS_DBG(7, "Each ip_vs_sync_conn entry needs %zd bytes\n",
1767                   sizeof(struct ip_vs_sync_conn_v0));
1768
1769         /* increase the module use count */
1770         if (!ip_vs_use_count_inc())
1771                 return -ENOPROTOOPT;
1772
1773         /* Do not hold one mutex and then to block on another */
1774         for (;;) {
1775                 rtnl_lock();
1776                 if (mutex_trylock(&ipvs->sync_mutex))
1777                         break;
1778                 rtnl_unlock();
1779                 mutex_lock(&ipvs->sync_mutex);
1780                 if (rtnl_trylock())
1781                         break;
1782                 mutex_unlock(&ipvs->sync_mutex);
1783         }
1784
1785         if (!ipvs->sync_state) {
1786                 count = clamp(sysctl_sync_ports(ipvs), 1, IPVS_SYNC_PORTS_MAX);
1787                 ipvs->threads_mask = count - 1;
1788         } else
1789                 count = ipvs->threads_mask + 1;
1790
1791         if (c->mcast_af == AF_UNSPEC) {
1792                 c->mcast_af = AF_INET;
1793                 c->mcast_group.ip = cpu_to_be32(IP_VS_SYNC_GROUP);
1794         }
1795         if (!c->mcast_port)
1796                 c->mcast_port = IP_VS_SYNC_PORT;
1797         if (!c->mcast_ttl)
1798                 c->mcast_ttl = 1;
1799
1800         dev = __dev_get_by_name(ipvs->net, c->mcast_ifn);
1801         if (!dev) {
1802                 pr_err("Unknown mcast interface: %s\n", c->mcast_ifn);
1803                 result = -ENODEV;
1804                 goto out_early;
1805         }
1806         hlen = (AF_INET6 == c->mcast_af) ?
1807                sizeof(struct ipv6hdr) + sizeof(struct udphdr) :
1808                sizeof(struct iphdr) + sizeof(struct udphdr);
1809         mtu = (state == IP_VS_STATE_BACKUP) ?
1810                   clamp(dev->mtu, 1500U, 65535U) : 1500U;
1811         min_mtu = (state == IP_VS_STATE_BACKUP) ? 1024 : 1;
1812
1813         if (c->sync_maxlen)
1814                 c->sync_maxlen = clamp_t(unsigned int,
1815                                          c->sync_maxlen, min_mtu,
1816                                          65535 - hlen);
1817         else
1818                 c->sync_maxlen = mtu - hlen;
1819
1820         if (state == IP_VS_STATE_MASTER) {
1821                 result = -EEXIST;
1822                 if (ipvs->ms)
1823                         goto out_early;
1824
1825                 ipvs->mcfg = *c;
1826                 name = "ipvs-m:%d:%d";
1827                 threadfn = sync_thread_master;
1828         } else if (state == IP_VS_STATE_BACKUP) {
1829                 result = -EEXIST;
1830                 if (ipvs->backup_tinfo)
1831                         goto out_early;
1832
1833                 ipvs->bcfg = *c;
1834                 name = "ipvs-b:%d:%d";
1835                 threadfn = sync_thread_backup;
1836         } else {
1837                 result = -EINVAL;
1838                 goto out_early;
1839         }
1840
1841         if (state == IP_VS_STATE_MASTER) {
1842                 struct ipvs_master_sync_state *ms;
1843
1844                 result = -ENOMEM;
1845                 ipvs->ms = kcalloc(count, sizeof(ipvs->ms[0]), GFP_KERNEL);
1846                 if (!ipvs->ms)
1847                         goto out;
1848                 ms = ipvs->ms;
1849                 for (id = 0; id < count; id++, ms++) {
1850                         INIT_LIST_HEAD(&ms->sync_queue);
1851                         ms->sync_queue_len = 0;
1852                         ms->sync_queue_delay = 0;
1853                         INIT_DELAYED_WORK(&ms->master_wakeup_work,
1854                                           master_wakeup_work_handler);
1855                         ms->ipvs = ipvs;
1856                 }
1857         }
1858         result = -ENOMEM;
1859         ti = kcalloc(count, sizeof(struct ip_vs_sync_thread_data),
1860                      GFP_KERNEL);
1861         if (!ti)
1862                 goto out;
1863
1864         for (id = 0; id < count; id++) {
1865                 tinfo = &ti[id];
1866                 tinfo->ipvs = ipvs;
1867                 if (state == IP_VS_STATE_BACKUP) {
1868                         result = -ENOMEM;
1869                         tinfo->buf = kmalloc(ipvs->bcfg.sync_maxlen,
1870                                              GFP_KERNEL);
1871                         if (!tinfo->buf)
1872                                 goto out;
1873                 }
1874                 tinfo->id = id;
1875                 if (state == IP_VS_STATE_MASTER)
1876                         result = make_send_sock(ipvs, id, dev, &tinfo->sock);
1877                 else
1878                         result = make_receive_sock(ipvs, id, dev, &tinfo->sock);
1879                 if (result < 0)
1880                         goto out;
1881
1882                 task = kthread_run(threadfn, tinfo, name, ipvs->gen, id);
1883                 if (IS_ERR(task)) {
1884                         result = PTR_ERR(task);
1885                         goto out;
1886                 }
1887                 tinfo->task = task;
1888         }
1889
1890         /* mark as active */
1891
1892         if (state == IP_VS_STATE_MASTER)
1893                 ipvs->master_tinfo = ti;
1894         else
1895                 ipvs->backup_tinfo = ti;
1896         spin_lock_bh(&ipvs->sync_buff_lock);
1897         ipvs->sync_state |= state;
1898         spin_unlock_bh(&ipvs->sync_buff_lock);
1899
1900         mutex_unlock(&ipvs->sync_mutex);
1901         rtnl_unlock();
1902
1903         return 0;
1904
1905 out:
1906         /* We do not need RTNL lock anymore, release it here so that
1907          * sock_release below can use rtnl_lock to leave the mcast group.
1908          */
1909         rtnl_unlock();
1910         id = min(id, count - 1);
1911         if (ti) {
1912                 for (tinfo = ti + id; tinfo >= ti; tinfo--) {
1913                         if (tinfo->task)
1914                                 kthread_stop(tinfo->task);
1915                 }
1916         }
1917         if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
1918                 kfree(ipvs->ms);
1919                 ipvs->ms = NULL;
1920         }
1921         mutex_unlock(&ipvs->sync_mutex);
1922
1923         /* No more mutexes, release socks */
1924         if (ti) {
1925                 for (tinfo = ti + id; tinfo >= ti; tinfo--) {
1926                         if (tinfo->sock)
1927                                 sock_release(tinfo->sock);
1928                         kfree(tinfo->buf);
1929                 }
1930                 kfree(ti);
1931         }
1932
1933         /* decrease the module use count */
1934         ip_vs_use_count_dec();
1935         return result;
1936
1937 out_early:
1938         mutex_unlock(&ipvs->sync_mutex);
1939         rtnl_unlock();
1940
1941         /* decrease the module use count */
1942         ip_vs_use_count_dec();
1943         return result;
1944 }
1945
1946
1947 int stop_sync_thread(struct netns_ipvs *ipvs, int state)
1948 {
1949         struct ip_vs_sync_thread_data *ti, *tinfo;
1950         int id;
1951         int retc = -EINVAL;
1952
1953         IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
1954
1955         mutex_lock(&ipvs->sync_mutex);
1956         if (state == IP_VS_STATE_MASTER) {
1957                 retc = -ESRCH;
1958                 if (!ipvs->ms)
1959                         goto err;
1960                 ti = ipvs->master_tinfo;
1961
1962                 /*
1963                  * The lock synchronizes with sb_queue_tail(), so that we don't
1964                  * add sync buffers to the queue, when we are already in
1965                  * progress of stopping the master sync daemon.
1966                  */
1967
1968                 spin_lock_bh(&ipvs->sync_buff_lock);
1969                 spin_lock(&ipvs->sync_lock);
1970                 ipvs->sync_state &= ~IP_VS_STATE_MASTER;
1971                 spin_unlock(&ipvs->sync_lock);
1972                 spin_unlock_bh(&ipvs->sync_buff_lock);
1973
1974                 retc = 0;
1975                 for (id = ipvs->threads_mask; id >= 0; id--) {
1976                         struct ipvs_master_sync_state *ms = &ipvs->ms[id];
1977                         int ret;
1978
1979                         tinfo = &ti[id];
1980                         pr_info("stopping master sync thread %d ...\n",
1981                                 task_pid_nr(tinfo->task));
1982                         cancel_delayed_work_sync(&ms->master_wakeup_work);
1983                         ret = kthread_stop(tinfo->task);
1984                         if (retc >= 0)
1985                                 retc = ret;
1986                 }
1987                 kfree(ipvs->ms);
1988                 ipvs->ms = NULL;
1989                 ipvs->master_tinfo = NULL;
1990         } else if (state == IP_VS_STATE_BACKUP) {
1991                 retc = -ESRCH;
1992                 if (!ipvs->backup_tinfo)
1993                         goto err;
1994                 ti = ipvs->backup_tinfo;
1995
1996                 ipvs->sync_state &= ~IP_VS_STATE_BACKUP;
1997                 retc = 0;
1998                 for (id = ipvs->threads_mask; id >= 0; id--) {
1999                         int ret;
2000
2001                         tinfo = &ti[id];
2002                         pr_info("stopping backup sync thread %d ...\n",
2003                                 task_pid_nr(tinfo->task));
2004                         ret = kthread_stop(tinfo->task);
2005                         if (retc >= 0)
2006                                 retc = ret;
2007                 }
2008                 ipvs->backup_tinfo = NULL;
2009         } else {
2010                 goto err;
2011         }
2012         id = ipvs->threads_mask;
2013         mutex_unlock(&ipvs->sync_mutex);
2014
2015         /* No more mutexes, release socks */
2016         for (tinfo = ti + id; tinfo >= ti; tinfo--) {
2017                 if (tinfo->sock)
2018                         sock_release(tinfo->sock);
2019                 kfree(tinfo->buf);
2020         }
2021         kfree(ti);
2022
2023         /* decrease the module use count */
2024         ip_vs_use_count_dec();
2025         return retc;
2026
2027 err:
2028         mutex_unlock(&ipvs->sync_mutex);
2029         return retc;
2030 }
2031
2032 /*
2033  * Initialize data struct for each netns
2034  */
2035 int __net_init ip_vs_sync_net_init(struct netns_ipvs *ipvs)
2036 {
2037         __mutex_init(&ipvs->sync_mutex, "ipvs->sync_mutex", &__ipvs_sync_key);
2038         spin_lock_init(&ipvs->sync_lock);
2039         spin_lock_init(&ipvs->sync_buff_lock);
2040         return 0;
2041 }
2042
2043 void ip_vs_sync_net_cleanup(struct netns_ipvs *ipvs)
2044 {
2045         int retc;
2046
2047         retc = stop_sync_thread(ipvs, IP_VS_STATE_MASTER);
2048         if (retc && retc != -ESRCH)
2049                 pr_err("Failed to stop Master Daemon\n");
2050
2051         retc = stop_sync_thread(ipvs, IP_VS_STATE_BACKUP);
2052         if (retc && retc != -ESRCH)
2053                 pr_err("Failed to stop Backup Daemon\n");
2054 }