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