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