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