root/lib/cluster/cpg.c

/* */

DEFINITIONS

1. pcmk__cpg_local_nodeid
2. crm_cs_flush_cb
3. crm_cs_flush
4. pcmk_cpg_dispatch
5. ais_dest
6. msg_type2text
7. check_message_sanity
8. pcmk__cpg_message_data
9. cmp_member_list_nodeid
10. cpgreason2str
11. peer_name
12. node_left
13. pcmk__cpg_confchg_cb
14. pcmk_cpg_set_deliver_fn
15. pcmk_cpg_set_confchg_fn
16. pcmk__cpg_connect
17. pcmk__cpg_disconnect
18. send_cpg_text
19. pcmk__cpg_send_xml

   1 /*
   2  * Copyright 2004-2025 the Pacemaker project contributors
   3  *
   4  * The version control history for this file may have further details.
   5  *
   6  * This source code is licensed under the GNU Lesser General Public License
   7  * version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.
   8  */
   9 
  10 #include <crm_internal.h>
  11 
  12 #include <arpa/inet.h>
  13 #include <inttypes.h>                   // PRIu32
  14 #include <netdb.h>
  15 #include <netinet/in.h>
  16 #include <stdbool.h>
  17 #include <stdint.h>                     // uint32_t
  18 #include <sys/socket.h>
  19 #include <sys/types.h>                  // size_t
  20 #include <sys/utsname.h>
  21 
  22 #include <bzlib.h>
  23 #include <corosync/corodefs.h>
  24 #include <corosync/corotypes.h>
  25 #include <corosync/hdb.h>
  26 #include <corosync/cpg.h>
  27 #include <qb/qbipc_common.h>
  28 #include <qb/qbipcc.h>
  29 #include <qb/qbutil.h>
  30 
  31 #include <crm/cluster/internal.h>
  32 #include <crm/common/ipc.h>
  33 #include <crm/common/ipc_internal.h>    // PCMK__SPECIAL_PID
  34 #include <crm/common/mainloop.h>
  35 #include <crm/common/xml.h>
  36 
  37 #include "crmcluster_private.h"
  38 
  39 /* @TODO Once we can update the public API to require pcmk_cluster_t* in more
  40  *       functions, we can ditch this in favor of cluster->cpg_handle.
  41  */
  42 static cpg_handle_t pcmk_cpg_handle = 0;
  43 
  44 // @TODO These could be moved to pcmk_cluster_t* at that time as well
  45 static bool cpg_evicted = false;
  46 static GList *cs_message_queue = NULL;
  47 static int cs_message_timer = 0;
  48 
  49 /* @COMPAT Any changes to these structs (other than renames) will break all
  50  * rolling upgrades, and should be avoided if possible or done at a major
  51  * version bump if not
  52  */
  53 
  54 struct pcmk__cpg_host_s {
  55     uint32_t id;
  56     uint32_t pid;
  57     gboolean local;             // Unused but needed for compatibility
  58     enum pcmk_ipc_server type;  // For logging only
  59     uint32_t size;
  60     char uname[MAX_NAME];
  61 } __attribute__ ((packed));
  62 
  63 typedef struct pcmk__cpg_host_s pcmk__cpg_host_t;
  64 
  65 struct pcmk__cpg_msg_s {
  66     struct qb_ipc_response_header header __attribute__ ((aligned(8)));
  67     uint32_t id;
  68     gboolean is_compressed;
  69 
  70     pcmk__cpg_host_t host;
  71     pcmk__cpg_host_t sender;
  72 
  73     uint32_t size;
  74     uint32_t compressed_size;
  75     /* 584 bytes */
  76     char data[0];
  77 
  78 } __attribute__ ((packed));
  79 
  80 typedef struct pcmk__cpg_msg_s pcmk__cpg_msg_t;
  81 
  82 static void crm_cs_flush(gpointer data);
  83 
  84 #define msg_data_len(msg) (msg->is_compressed?msg->compressed_size:msg->size)
  85 
  86 #define cs_repeat(rc, counter, max, code) do {                          \
  87         rc = code;                                                      \
  88         if ((rc == CS_ERR_TRY_AGAIN) || (rc == CS_ERR_QUEUE_FULL)) {    \
  89             counter++;                                                  \
  90             crm_debug("Retrying operation after %ds", counter);         \
  91             sleep(counter);                                             \
  92         } else {                                                        \
  93             break;                                                      \
  94         }                                                               \
  95     } while (counter < max)
  96 
  97 /*!
  98  * \internal
  99  * \brief Get the local Corosync node ID (via CPG)
 100  *
 101  * \param[in] handle  CPG connection to use (or 0 to use new connection)
 102  *
 103  * \return Corosync ID of local node (or 0 if not known)
 104  */
 105 uint32_t
 106 pcmk__cpg_local_nodeid(cpg_handle_t handle)
     /*  */
 107 {
 108     cs_error_t rc = CS_OK;
 109     int retries = 0;
 110     static uint32_t local_nodeid = 0;
 111     cpg_handle_t local_handle = handle;
 112     cpg_model_v1_data_t cpg_model_info = {CPG_MODEL_V1, NULL, NULL, NULL, 0};
 113     int fd = -1;
 114     uid_t found_uid = 0;
 115     gid_t found_gid = 0;
 116     pid_t found_pid = 0;
 117     int rv = 0;
 118 
 119     if (local_nodeid != 0) {
 120         return local_nodeid;
 121     }
 122 
 123     if (handle == 0) {
 124         crm_trace("Creating connection");
 125         cs_repeat(rc, retries, 5,
 126                   cpg_model_initialize(&local_handle, CPG_MODEL_V1,
 127                                        (cpg_model_data_t *) &cpg_model_info,
 128                                        NULL));
 129         if (rc != CS_OK) {
 130             crm_err("Could not connect to the CPG API: %s (%d)",
 131                     cs_strerror(rc), rc);
 132             return 0;
 133         }
 134 
 135         rc = cpg_fd_get(local_handle, &fd);
 136         if (rc != CS_OK) {
 137             crm_err("Could not obtain the CPG API connection: %s (%d)",
 138                     cs_strerror(rc), rc);
 139             goto bail;
 140         }
 141 
 142         // CPG provider run as root (at least in given user namespace)?
 143         rv = crm_ipc_is_authentic_process(fd, (uid_t) 0, (gid_t) 0, &found_pid,
 144                                           &found_uid, &found_gid);
 145         if (rv == 0) {
 146             crm_err("CPG provider is not authentic:"
 147                     " process %lld (uid: %lld, gid: %lld)",
 148                     (long long) PCMK__SPECIAL_PID_AS_0(found_pid),
 149                     (long long) found_uid, (long long) found_gid);
 150             goto bail;
 151 
 152         } else if (rv < 0) {
 153             crm_err("Could not verify authenticity of CPG provider: %s (%d)",
 154                     strerror(-rv), -rv);
 155             goto bail;
 156         }
 157     }
 158 
 159     if (rc == CS_OK) {
 160         retries = 0;
 161         crm_trace("Performing lookup");
 162         cs_repeat(rc, retries, 5, cpg_local_get(local_handle, &local_nodeid));
 163     }
 164 
 165     if (rc != CS_OK) {
 166         crm_err("Could not get local node id from the CPG API: %s (%d)",
 167                 pcmk__cs_err_str(rc), rc);
 168     }
 169 
 170 bail:
 171     if (handle == 0) {
 172         crm_trace("Closing connection");
 173         cpg_finalize(local_handle);
 174     }
 175     crm_debug("Local nodeid is %u", local_nodeid);
 176     return local_nodeid;
 177 }
 178 
 179 /*!
 180  * \internal
 181  * \brief Callback function for Corosync message queue timer
 182  *
 183  * \param[in] data  CPG handle
 184  *
 185  * \return FALSE (to indicate to glib that timer should not be removed)
 186  */
 187 static gboolean
 188 crm_cs_flush_cb(gpointer data)
     /*  */
 189 {
 190     cs_message_timer = 0;
 191     crm_cs_flush(data);
 192     return FALSE;
 193 }
 194 
 195 // Send no more than this many CPG messages in one flush
 196 #define CS_SEND_MAX 200
 197 
 198 /*!
 199  * \internal
 200  * \brief Send messages in Corosync CPG message queue
 201  *
 202  * \param[in] data   CPG handle
 203  */
 204 static void
 205 crm_cs_flush(gpointer data)
     /*  */
 206 {
 207     unsigned int sent = 0;
 208     guint queue_len = 0;
 209     cs_error_t rc = 0;
 210     cpg_handle_t *handle = (cpg_handle_t *) data;
 211 
 212     if (*handle == 0) {
 213         crm_trace("Connection is dead");
 214         return;
 215     }
 216 
 217     queue_len = g_list_length(cs_message_queue);
 218     if (((queue_len % 1000) == 0) && (queue_len > 1)) {
 219         crm_err("CPG queue has grown to %d", queue_len);
 220 
 221     } else if (queue_len == CS_SEND_MAX) {
 222         crm_warn("CPG queue has grown to %d", queue_len);
 223     }
 224 
 225     if (cs_message_timer != 0) {
 226         /* There is already a timer, wait until it goes off */
 227         crm_trace("Timer active %d", cs_message_timer);
 228         return;
 229     }
 230 
 231     while ((cs_message_queue != NULL) && (sent < CS_SEND_MAX)) {
 232         struct iovec *iov = cs_message_queue->data;
 233 
 234         rc = cpg_mcast_joined(*handle, CPG_TYPE_AGREED, iov, 1);
 235         if (rc != CS_OK) {
 236             break;
 237         }
 238 
 239         sent++;
 240         crm_trace("CPG message sent, size=%zu", iov->iov_len);
 241 
 242         cs_message_queue = g_list_remove(cs_message_queue, iov);
 243         free(iov->iov_base);
 244         free(iov);
 245     }
 246 
 247     queue_len -= sent;
 248     do_crm_log((queue_len > 5)? LOG_INFO : LOG_TRACE,
 249                "Sent %u CPG message%s (%d still queued): %s (rc=%d)",
 250                sent, pcmk__plural_s(sent), queue_len, pcmk__cs_err_str(rc),
 251                (int) rc);
 252 
 253     if (cs_message_queue) {
 254         uint32_t delay_ms = 100;
 255         if (rc != CS_OK) {
 256             /* Proportionally more if sending failed but cap at 1s */
 257             delay_ms = QB_MIN(1000, CS_SEND_MAX + (10 * queue_len));
 258         }
 259         cs_message_timer = pcmk__create_timer(delay_ms, crm_cs_flush_cb, data);
 260     }
 261 }
 262 
 263 /*!
 264  * \internal
 265  * \brief Dispatch function for CPG handle
 266  *
 267  * \param[in,out] user_data  Cluster object
 268  *
 269  * \return 0 on success, -1 on error (per mainloop_io_t interface)
 270  */
 271 static int
 272 pcmk_cpg_dispatch(gpointer user_data)
     /*  */
 273 {
 274     cs_error_t rc = CS_OK;
 275     pcmk_cluster_t *cluster = (pcmk_cluster_t *) user_data;
 276 
 277     rc = cpg_dispatch(cluster->priv->cpg_handle, CS_DISPATCH_ONE);
 278     if (rc != CS_OK) {
 279         crm_err("Connection to the CPG API failed: %s (%d)",
 280                 pcmk__cs_err_str(rc), rc);
 281         cpg_finalize(cluster->priv->cpg_handle);
 282         cluster->priv->cpg_handle = 0;
 283         return -1;
 284 
 285     } else if (cpg_evicted) {
 286         crm_err("Evicted from CPG membership");
 287         return -1;
 288     }
 289     return 0;
 290 }
 291 
 292 static inline const char *
 293 ais_dest(const pcmk__cpg_host_t *host)
     /*  */
 294 {
 295     return (host->size > 0)? host->uname : "<all>";
 296 }
 297 
 298 static inline const char *
 299 msg_type2text(enum pcmk_ipc_server type)
     /*  */
 300 {
 301     const char *name = pcmk__server_message_type(type);
 302 
 303     return pcmk__s(name, "unknown");
 304 }
 305 
 306 /*!
 307  * \internal
 308  * \brief Check whether a Corosync CPG message is valid
 309  *
 310  * \param[in] msg   Corosync CPG message to check
 311  *
 312  * \return true if \p msg is valid, otherwise false
 313  */
 314 static bool
 315 check_message_sanity(const pcmk__cpg_msg_t *msg)
     /*  */
 316 {
 317     int32_t payload_size = msg->header.size - sizeof(pcmk__cpg_msg_t);
 318 
 319     if (payload_size < 1) {
 320         crm_err("%sCPG message %d from %s invalid: "
 321                 "Claimed size of %d bytes is too small "
 322                 QB_XS " from %s[%u] to %s@%s",
 323                 (msg->is_compressed? "Compressed " : ""),
 324                 msg->id, ais_dest(&(msg->sender)),
 325                 (int) msg->header.size,
 326                 msg_type2text(msg->sender.type), msg->sender.pid,
 327                 msg_type2text(msg->host.type), ais_dest(&(msg->host)));
 328         return false;
 329     }
 330 
 331     if (msg->header.error != CS_OK) {
 332         crm_err("%sCPG message %d from %s invalid: "
 333                 "Sender indicated error %d "
 334                 QB_XS " from %s[%u] to %s@%s",
 335                 (msg->is_compressed? "Compressed " : ""),
 336                 msg->id, ais_dest(&(msg->sender)),
 337                 msg->header.error,
 338                 msg_type2text(msg->sender.type), msg->sender.pid,
 339                 msg_type2text(msg->host.type), ais_dest(&(msg->host)));
 340         return false;
 341     }
 342 
 343     if (msg_data_len(msg) != payload_size) {
 344         crm_err("%sCPG message %d from %s invalid: "
 345                 "Total size %d inconsistent with payload size %d "
 346                 QB_XS " from %s[%u] to %s@%s",
 347                 (msg->is_compressed? "Compressed " : ""),
 348                 msg->id, ais_dest(&(msg->sender)),
 349                 (int) msg->header.size, (int) msg_data_len(msg),
 350                 msg_type2text(msg->sender.type), msg->sender.pid,
 351                 msg_type2text(msg->host.type), ais_dest(&(msg->host)));
 352         return false;
 353     }
 354 
 355     if (!msg->is_compressed &&
 356         /* msg->size != (strlen(msg->data) + 1) would be a stronger check,
 357          * but checking the last byte or two should be quick
 358          */
 359         (((msg->size > 1) && (msg->data[msg->size - 2] == '\0'))
 360          || (msg->data[msg->size - 1] != '\0'))) {
 361         crm_err("CPG message %d from %s invalid: "
 362                 "Payload does not end at byte %" PRIu32 " "
 363                 QB_XS " from %s[%u] to %s@%s",
 364                 msg->id, ais_dest(&(msg->sender)), msg->size,
 365                 msg_type2text(msg->sender.type), msg->sender.pid,
 366                 msg_type2text(msg->host.type), ais_dest(&(msg->host)));
 367         return false;
 368     }
 369 
 370     crm_trace("Verified %d-byte %sCPG message %d from %s[%u]@%s to %s@%s",
 371               (int) msg->header.size, (msg->is_compressed? "compressed " : ""),
 372               msg->id, msg_type2text(msg->sender.type), msg->sender.pid,
 373               ais_dest(&(msg->sender)),
 374               msg_type2text(msg->host.type), ais_dest(&(msg->host)));
 375     return true;
 376 }
 377 
 378 /*!
 379  * \internal
 380  * \brief Extract text data from a Corosync CPG message
 381  *
 382  * \param[in]     handle     CPG connection (to get local node ID if not known)
 383  * \param[in]     sender_id  Corosync ID of node that sent message
 384  * \param[in]     pid        Process ID of message sender (for logging only)
 385  * \param[in,out] content    CPG message
 386  * \param[out]    from       If not \c NULL, will be set to sender uname
 387  *                           (valid for the lifetime of \p content)
 388  *
 389  * \return Newly allocated string with message data, or NULL for errors and
 390  *         messages not intended for the local node
 391  *
 392  * \note The caller is responsible for freeing the return value using \c free().
 393  */
 394 char *
 395 pcmk__cpg_message_data(cpg_handle_t handle, uint32_t sender_id, uint32_t pid,
     /*  */
 396                        void *content, const char **from)
 397 {
 398     char *data = NULL;
 399     pcmk__cpg_msg_t *msg = content;
 400 
 401     if (from != NULL) {
 402         *from = NULL;
 403     }
 404 
 405     if (handle != 0) {
 406         uint32_t local_nodeid = pcmk__cpg_local_nodeid(handle);
 407         const char *local_name = pcmk__cluster_local_node_name();
 408 
 409         // Update or validate message sender ID
 410         if (msg->sender.id == 0) {
 411             msg->sender.id = sender_id;
 412         } else if (msg->sender.id != sender_id) {
 413             crm_warn("Ignoring CPG message from ID %" PRIu32 " PID %" PRIu32
 414                      ": claimed ID %" PRIu32,
 415                     sender_id, pid, msg->sender.id);
 416             return NULL;
 417         }
 418 
 419         // Ignore messages that aren't for the local node
 420         if ((msg->host.id != 0) && (local_nodeid != msg->host.id)) {
 421             crm_trace("Ignoring CPG message from ID %" PRIu32 " PID %" PRIu32
 422                       ": for ID %" PRIu32 " not %" PRIu32,
 423                       sender_id, pid, msg->host.id, local_nodeid);
 424             return NULL;
 425         }
 426         if ((msg->host.size > 0)
 427             && !pcmk__str_eq(msg->host.uname, local_name, pcmk__str_casei)) {
 428 
 429             crm_trace("Ignoring CPG message from ID %" PRIu32 " PID %" PRIu32
 430                       ": for name %s not %s",
 431                       sender_id, pid, msg->host.uname, local_name);
 432             return NULL;
 433         }
 434 
 435         // Add sender name if not in original message
 436         if (msg->sender.size == 0) {
 437             const pcmk__node_status_t *peer =
 438                 pcmk__get_node(sender_id, NULL, NULL,
 439                                pcmk__node_search_cluster_member);
 440 
 441             if (peer->name == NULL) {
 442                 crm_debug("Received CPG message from node with ID %" PRIu32
 443                           " but its name is unknown", sender_id);
 444             } else {
 445                 crm_debug("Updating name of CPG message sender with ID %" PRIu32
 446                           " to %s", sender_id, peer->name);
 447                 msg->sender.size = strlen(peer->name);
 448                 memset(msg->sender.uname, 0, MAX_NAME);
 449                 memcpy(msg->sender.uname, peer->name, msg->sender.size);
 450             }
 451         }
 452     }
 453 
 454     // Ensure sender is in peer cache (though it should already be)
 455     pcmk__get_node(msg->sender.id, msg->sender.uname, NULL,
 456                    pcmk__node_search_cluster_member);
 457 
 458     if (from != NULL) {
 459         *from = msg->sender.uname;
 460     }
 461 
 462     if (!check_message_sanity(msg)) {
 463         return NULL;
 464     }
 465 
 466     if (msg->is_compressed && (msg->size > 0)) {
 467         int rc = BZ_OK;
 468         unsigned int new_size = msg->size + 1;
 469         char *uncompressed = pcmk__assert_alloc(1, new_size);
 470 
 471         rc = BZ2_bzBuffToBuffDecompress(uncompressed, &new_size, msg->data,
 472                                         msg->compressed_size, 1, 0);
 473         rc = pcmk__bzlib2rc(rc);
 474         if ((rc == pcmk_rc_ok) && (msg->size != new_size)) { // libbz2 bug?
 475             rc = pcmk_rc_compression;
 476         }
 477         if (rc != pcmk_rc_ok) {
 478             free(uncompressed);
 479             crm_warn("Ignoring compressed CPG message %d from %s (ID %" PRIu32
 480                     " PID %" PRIu32 "): %s",
 481                      msg->id, ais_dest(&(msg->sender)), sender_id, pid,
 482                      pcmk_rc_str(rc));
 483             return NULL;
 484         }
 485         data = uncompressed;
 486 
 487     } else {
 488         data = pcmk__str_copy(msg->data);
 489     }
 490 
 491     crm_trace("Received %sCPG message %d from %s (ID %" PRIu32
 492               " PID %" PRIu32 "): %.40s...",
 493               (msg->is_compressed? "compressed " : ""),
 494               msg->id, ais_dest(&(msg->sender)), sender_id, pid, msg->data);
 495     return data;
 496 }
 497 
 498 /*!
 499  * \internal
 500  * \brief Compare cpg_address objects by node ID
 501  *
 502  * \param[in] first   First cpg_address structure to compare
 503  * \param[in] second  Second cpg_address structure to compare
 504  *
 505  * \return Negative number if first's node ID is lower,
 506  *         positive number if first's node ID is greater,
 507  *         or 0 if both node IDs are equal
 508  */
 509 static int
 510 cmp_member_list_nodeid(const void *first, const void *second)
     /*  */
 511 {
 512     const struct cpg_address *const a = *((const struct cpg_address **) first),
 513                              *const b = *((const struct cpg_address **) second);
 514     if (a->nodeid < b->nodeid) {
 515         return -1;
 516     } else if (a->nodeid > b->nodeid) {
 517         return 1;
 518     }
 519     /* don't bother with "reason" nor "pid" */
 520     return 0;
 521 }
 522 
 523 /*!
 524  * \internal
 525  * \brief Get a readable string equivalent of a cpg_reason_t value
 526  *
 527  * \param[in] reason  CPG reason value
 528  *
 529  * \return Readable string suitable for logging
 530  */
 531 static const char *
 532 cpgreason2str(cpg_reason_t reason)
     /*  */
 533 {
 534     switch (reason) {
 535         case CPG_REASON_JOIN:       return " via cpg_join";
 536         case CPG_REASON_LEAVE:      return " via cpg_leave";
 537         case CPG_REASON_NODEDOWN:   return " via cluster exit";
 538         case CPG_REASON_NODEUP:     return " via cluster join";
 539         case CPG_REASON_PROCDOWN:   return " for unknown reason";
 540         default:                    break;
 541     }
 542     return "";
 543 }
 544 
 545 /*!
 546  * \internal
 547  * \brief Get a log-friendly node name
 548  *
 549  * \param[in] peer  Node to check
 550  *
 551  * \return Node's uname, or readable string if not known
 552  */
 553 static inline const char *
 554 peer_name(const pcmk__node_status_t *peer)
     /*  */
 555 {
 556     return (peer != NULL)? pcmk__s(peer->name, "peer node") : "unknown node";
 557 }
 558 
 559 /*!
 560  * \internal
 561  * \brief Process a CPG peer's leaving the cluster
 562  *
 563  * \param[in] cpg_group_name      CPG group name (for logging)
 564  * \param[in] event_counter       Event number (for logging)
 565  * \param[in] local_nodeid        Node ID of local node
 566  * \param[in] cpg_peer            CPG peer that left
 567  * \param[in] sorted_member_list  List of remaining members, qsort()-ed by ID
 568  * \param[in] member_list_entries Number of entries in \p sorted_member_list
 569  */
 570 static void
 571 node_left(const char *cpg_group_name, int event_counter,
     /*  */
 572           uint32_t local_nodeid, const struct cpg_address *cpg_peer,
 573           const struct cpg_address **sorted_member_list,
 574           size_t member_list_entries)
 575 {
 576     pcmk__node_status_t *peer =
 577         pcmk__search_node_caches(cpg_peer->nodeid, NULL, NULL,
 578                                  pcmk__node_search_cluster_member);
 579     const struct cpg_address **rival = NULL;
 580 
 581     /* Most CPG-related Pacemaker code assumes that only one process on a node
 582      * can be in the process group, but Corosync does not impose this
 583      * limitation, and more than one can be a member in practice due to a
 584      * daemon attempting to start while another instance is already running.
 585      *
 586      * Check for any such duplicate instances, because we don't want to process
 587      * their leaving as if our actual peer left. If the peer that left still has
 588      * an entry in sorted_member_list (with a different PID), we will ignore the
 589      * leaving.
 590      *
 591      * @TODO Track CPG members' PIDs so we can tell exactly who left.
 592      */
 593     if (peer != NULL) {
 594         rival = bsearch(&cpg_peer, sorted_member_list, member_list_entries,
 595                         sizeof(const struct cpg_address *),
 596                         cmp_member_list_nodeid);
 597     }
 598 
 599     if (rival == NULL) {
 600         crm_info("Group %s event %d: %s (node %u pid %u) left%s",
 601                  cpg_group_name, event_counter, peer_name(peer),
 602                  cpg_peer->nodeid, cpg_peer->pid,
 603                  cpgreason2str(cpg_peer->reason));
 604         if (peer != NULL) {
 605             crm_update_peer_proc(__func__, peer, crm_proc_cpg,
 606                                  PCMK_VALUE_OFFLINE);
 607         }
 608     } else if (cpg_peer->nodeid == local_nodeid) {
 609         crm_warn("Group %s event %d: duplicate local pid %u left%s",
 610                  cpg_group_name, event_counter,
 611                  cpg_peer->pid, cpgreason2str(cpg_peer->reason));
 612     } else {
 613         crm_warn("Group %s event %d: "
 614                  "%s (node %u) duplicate pid %u left%s (%u remains)",
 615                  cpg_group_name, event_counter, peer_name(peer),
 616                  cpg_peer->nodeid, cpg_peer->pid,
 617                  cpgreason2str(cpg_peer->reason), (*rival)->pid);
 618     }
 619 }
 620 
 621 /*!
 622  * \internal
 623  * \brief Handle a CPG configuration change event
 624  *
 625  * \param[in] handle               CPG connection
 626  * \param[in] group_name           CPG group name
 627  * \param[in] member_list          List of current CPG members
 628  * \param[in] member_list_entries  Number of entries in \p member_list
 629  * \param[in] left_list            List of CPG members that left
 630  * \param[in] left_list_entries    Number of entries in \p left_list
 631  * \param[in] joined_list          List of CPG members that joined
 632  * \param[in] joined_list_entries  Number of entries in \p joined_list
 633  *
 634  * \note This is of type \c cpg_confchg_fn_t, intended to be used in a
 635  *       \c cpg_callbacks_t object.
 636  */
 637 void
 638 pcmk__cpg_confchg_cb(cpg_handle_t handle,
     /*  */
 639                      const struct cpg_name *group_name,
 640                      const struct cpg_address *member_list,
 641                      size_t member_list_entries,
 642                      const struct cpg_address *left_list,
 643                      size_t left_list_entries,
 644                      const struct cpg_address *joined_list,
 645                      size_t joined_list_entries)
 646 {
 647     static int counter = 0;
 648 
 649     bool found = false;
 650     uint32_t local_nodeid = pcmk__cpg_local_nodeid(handle);
 651     const struct cpg_address **sorted = NULL;
 652 
 653     sorted = pcmk__assert_alloc(member_list_entries,
 654                                 sizeof(const struct cpg_address *));
 655 
 656     for (size_t iter = 0; iter < member_list_entries; iter++) {
 657         sorted[iter] = member_list + iter;
 658     }
 659 
 660     // So that the cross-matching of multiply-subscribed nodes is then cheap
 661     qsort(sorted, member_list_entries, sizeof(const struct cpg_address *),
 662           cmp_member_list_nodeid);
 663 
 664     for (int i = 0; i < left_list_entries; i++) {
 665         node_left(group_name->value, counter, local_nodeid, &left_list[i],
 666                   sorted, member_list_entries);
 667     }
 668     free(sorted);
 669     sorted = NULL;
 670 
 671     for (int i = 0; i < joined_list_entries; i++) {
 672         crm_info("Group %s event %d: node %u pid %u joined%s",
 673                  group_name->value, counter, joined_list[i].nodeid,
 674                  joined_list[i].pid, cpgreason2str(joined_list[i].reason));
 675     }
 676 
 677     for (int i = 0; i < member_list_entries; i++) {
 678         pcmk__node_status_t *peer =
 679             pcmk__get_node(member_list[i].nodeid, NULL, NULL,
 680                            pcmk__node_search_cluster_member);
 681 
 682         if (member_list[i].nodeid == local_nodeid
 683                 && member_list[i].pid != getpid()) {
 684             // See the note in node_left()
 685             crm_warn("Group %s event %d: detected duplicate local pid %u",
 686                      group_name->value, counter, member_list[i].pid);
 687             continue;
 688         }
 689         crm_info("Group %s event %d: %s (node %u pid %u) is member",
 690                  group_name->value, counter, peer_name(peer),
 691                  member_list[i].nodeid, member_list[i].pid);
 692 
 693         /* If the caller left auto-reaping enabled, this will also update the
 694          * state to member.
 695          */
 696         peer = crm_update_peer_proc(__func__, peer, crm_proc_cpg,
 697                                     PCMK_VALUE_ONLINE);
 698 
 699         if (peer && peer->state && strcmp(peer->state, PCMK_VALUE_MEMBER)) {
 700             /* The node is a CPG member, but we currently think it's not a
 701              * cluster member. This is possible only if auto-reaping was
 702              * disabled. The node may be joining, and we happened to get the CPG
 703              * notification before the quorum notification; or the node may have
 704              * just died, and we are processing its final messages; or a bug
 705              * has affected the peer cache.
 706              */
 707             time_t now = time(NULL);
 708 
 709             if (peer->when_lost == 0) {
 710                 // Track when we first got into this contradictory state
 711                 peer->when_lost = now;
 712 
 713             } else if (now > (peer->when_lost + 60)) {
 714                 // If it persists for more than a minute, update the state
 715                 crm_warn("Node %u is member of group %s but was believed "
 716                          "offline",
 717                          member_list[i].nodeid, group_name->value);
 718                 pcmk__update_peer_state(__func__, peer, PCMK_VALUE_MEMBER, 0);
 719             }
 720         }
 721 
 722         if (local_nodeid == member_list[i].nodeid) {
 723             found = true;
 724         }
 725     }
 726 
 727     if (!found) {
 728         crm_err("Local node was evicted from group %s", group_name->value);
 729         cpg_evicted = true;
 730     }
 731 
 732     counter++;
 733 }
 734 
 735 /*!
 736  * \brief Set the CPG deliver callback function for a cluster object
 737  *
 738  * \param[in,out] cluster  Cluster object
 739  * \param[in]     fn       Deliver callback function to set
 740  *
 741  * \return Standard Pacemaker return code
 742  */
 743 int
 744 pcmk_cpg_set_deliver_fn(pcmk_cluster_t *cluster, cpg_deliver_fn_t fn)
     /*  */
 745 {
 746     if (cluster == NULL) {
 747         return EINVAL;
 748     }
 749     cluster->cpg.cpg_deliver_fn = fn;
 750     return pcmk_rc_ok;
 751 }
 752 
 753 /*!
 754  * \brief Set the CPG config change callback function for a cluster object
 755  *
 756  * \param[in,out] cluster  Cluster object
 757  * \param[in]     fn       Configuration change callback function to set
 758  *
 759  * \return Standard Pacemaker return code
 760  */
 761 int
 762 pcmk_cpg_set_confchg_fn(pcmk_cluster_t *cluster, cpg_confchg_fn_t fn)
     /*  */
 763 {
 764     if (cluster == NULL) {
 765         return EINVAL;
 766     }
 767     cluster->cpg.cpg_confchg_fn = fn;
 768     return pcmk_rc_ok;
 769 }
 770 
 771 /*!
 772  * \brief Connect to Corosync CPG
 773  *
 774  * \param[in,out] cluster  Initialized cluster object to connect
 775  *
 776  * \return Standard Pacemaker return code
 777  */
 778 int
 779 pcmk__cpg_connect(pcmk_cluster_t *cluster)
     /*  */
 780 {
 781     cs_error_t rc;
 782     int fd = -1;
 783     int retries = 0;
 784     uint32_t id = 0;
 785     pcmk__node_status_t *peer = NULL;
 786     cpg_handle_t handle = 0;
 787     const char *cpg_group_name = NULL;
 788     uid_t found_uid = 0;
 789     gid_t found_gid = 0;
 790     pid_t found_pid = 0;
 791     int rv;
 792 
 793     struct mainloop_fd_callbacks cpg_fd_callbacks = {
 794         .dispatch = pcmk_cpg_dispatch,
 795         .destroy = cluster->destroy,
 796     };
 797 
 798     cpg_model_v1_data_t cpg_model_info = {
 799             .model = CPG_MODEL_V1,
 800             .cpg_deliver_fn = cluster->cpg.cpg_deliver_fn,
 801             .cpg_confchg_fn = cluster->cpg.cpg_confchg_fn,
 802             .cpg_totem_confchg_fn = NULL,
 803             .flags = 0,
 804     };
 805 
 806     cpg_evicted = false;
 807 
 808     if (cluster->priv->server != pcmk_ipc_unknown) {
 809         cpg_group_name = pcmk__server_message_type(cluster->priv->server);
 810     }
 811 
 812     if (cpg_group_name == NULL) {
 813         /* The name will already be non-NULL for Pacemaker servers. If a
 814          * command-line tool or external caller connects to the cluster,
 815          * they will join this CPG group.
 816          */
 817         cpg_group_name = pcmk__s(crm_system_name, "unknown");
 818     }
 819     memset(cluster->priv->group.value, 0, 128);
 820     strncpy(cluster->priv->group.value, cpg_group_name, 127);
 821     cluster->priv->group.length = strlen(cluster->priv->group.value) + 1;
 822 
 823     cs_repeat(rc, retries, 30, cpg_model_initialize(&handle, CPG_MODEL_V1, (cpg_model_data_t *)&cpg_model_info, NULL));
 824     if (rc != CS_OK) {
 825         crm_err("Could not connect to the CPG API: %s (%d)",
 826                 cs_strerror(rc), rc);
 827         goto bail;
 828     }
 829 
 830     rc = cpg_fd_get(handle, &fd);
 831     if (rc != CS_OK) {
 832         crm_err("Could not obtain the CPG API connection: %s (%d)",
 833                 cs_strerror(rc), rc);
 834         goto bail;
 835     }
 836 
 837     /* CPG provider run as root (in given user namespace, anyway)? */
 838     if (!(rv = crm_ipc_is_authentic_process(fd, (uid_t) 0,(gid_t) 0, &found_pid,
 839                                             &found_uid, &found_gid))) {
 840         crm_err("CPG provider is not authentic:"
 841                 " process %lld (uid: %lld, gid: %lld)",
 842                 (long long) PCMK__SPECIAL_PID_AS_0(found_pid),
 843                 (long long) found_uid, (long long) found_gid);
 844         rc = CS_ERR_ACCESS;
 845         goto bail;
 846     } else if (rv < 0) {
 847         crm_err("Could not verify authenticity of CPG provider: %s (%d)",
 848                 strerror(-rv), -rv);
 849         rc = CS_ERR_ACCESS;
 850         goto bail;
 851     }
 852 
 853     id = pcmk__cpg_local_nodeid(handle);
 854     if (id == 0) {
 855         crm_err("Could not get local node id from the CPG API");
 856         goto bail;
 857 
 858     }
 859     cluster->priv->node_id = id;
 860 
 861     retries = 0;
 862     cs_repeat(rc, retries, 30, cpg_join(handle, &cluster->priv->group));
 863     if (rc != CS_OK) {
 864         crm_err("Could not join the CPG group '%s': %d", cpg_group_name, rc);
 865         goto bail;
 866     }
 867 
 868     pcmk_cpg_handle = handle;
 869     cluster->priv->cpg_handle = handle;
 870     mainloop_add_fd("corosync-cpg", G_PRIORITY_MEDIUM, fd, cluster, &cpg_fd_callbacks);
 871 
 872   bail:
 873     if (rc != CS_OK) {
 874         cpg_finalize(handle);
 875         // @TODO Map rc to more specific Pacemaker return code
 876         return ENOTCONN;
 877     }
 878 
 879     peer = pcmk__get_node(id, NULL, NULL, pcmk__node_search_cluster_member);
 880     crm_update_peer_proc(__func__, peer, crm_proc_cpg, PCMK_VALUE_ONLINE);
 881     return pcmk_rc_ok;
 882 }
 883 
 884 /*!
 885  * \internal
 886  * \brief Disconnect from Corosync CPG
 887  *
 888  * \param[in,out] cluster  Cluster object to disconnect
 889  */
 890 void
 891 pcmk__cpg_disconnect(pcmk_cluster_t *cluster)
     /*  */
 892 {
 893     pcmk_cpg_handle = 0;
 894     if (cluster->priv->cpg_handle != 0) {
 895         crm_trace("Disconnecting CPG");
 896         cpg_leave(cluster->priv->cpg_handle, &cluster->priv->group);
 897         cpg_finalize(cluster->priv->cpg_handle);
 898         cluster->priv->cpg_handle = 0;
 899 
 900     } else {
 901         crm_info("No CPG connection");
 902     }
 903 }
 904 
 905 /*!
 906  * \internal
 907  * \brief Send string data via Corosync CPG
 908  *
 909  * \param[in] data   Data to send
 910  * \param[in] node   Cluster node to send message to
 911  * \param[in] dest   Type of message to send
 912  *
 913  * \return \c true on success, or \c false otherwise
 914  */
 915 static bool
 916 send_cpg_text(const char *data, const pcmk__node_status_t *node,
     /*  */
 917               enum pcmk_ipc_server dest)
 918 {
 919     static int msg_id = 0;
 920     static int local_pid = 0;
 921     static int local_name_len = 0;
 922     static const char *local_name = NULL;
 923 
 924     char *target = NULL;
 925     struct iovec *iov;
 926     pcmk__cpg_msg_t *msg = NULL;
 927 
 928     if (local_name == NULL) {
 929         local_name = pcmk__cluster_local_node_name();
 930     }
 931     if ((local_name_len == 0) && (local_name != NULL)) {
 932         local_name_len = strlen(local_name);
 933     }
 934 
 935     if (data == NULL) {
 936         data = "";
 937     }
 938 
 939     if (local_pid == 0) {
 940         local_pid = getpid();
 941     }
 942 
 943     msg = pcmk__assert_alloc(1, sizeof(pcmk__cpg_msg_t));
 944 
 945     msg_id++;
 946     msg->id = msg_id;
 947     msg->header.error = CS_OK;
 948 
 949     msg->host.type = dest;
 950 
 951     if (node != NULL) {
 952         if (node->name != NULL) {
 953             target = pcmk__str_copy(node->name);
 954             msg->host.size = strlen(node->name);
 955             memset(msg->host.uname, 0, MAX_NAME);
 956             memcpy(msg->host.uname, node->name, msg->host.size);
 957 
 958         } else {
 959             target = crm_strdup_printf("%" PRIu32, node->cluster_layer_id);
 960         }
 961         msg->host.id = node->cluster_layer_id;
 962 
 963     } else {
 964         target = pcmk__str_copy("all");
 965     }
 966 
 967     msg->sender.id = 0;
 968     msg->sender.type = pcmk__parse_server(crm_system_name);
 969     msg->sender.pid = local_pid;
 970     msg->sender.size = local_name_len;
 971     memset(msg->sender.uname, 0, MAX_NAME);
 972 
 973     if ((local_name != NULL) && (msg->sender.size != 0)) {
 974         memcpy(msg->sender.uname, local_name, msg->sender.size);
 975     }
 976 
 977     msg->size = 1 + strlen(data);
 978     msg->header.size = sizeof(pcmk__cpg_msg_t) + msg->size;
 979 
 980     if (msg->size < CRM_BZ2_THRESHOLD) {
 981         msg = pcmk__realloc(msg, msg->header.size);
 982         memcpy(msg->data, data, msg->size);
 983 
 984     } else {
 985         char *compressed = NULL;
 986         unsigned int new_size = 0;
 987 
 988         if (pcmk__compress(data, (unsigned int) msg->size, 0, &compressed,
 989                            &new_size) == pcmk_rc_ok) {
 990 
 991             msg->header.size = sizeof(pcmk__cpg_msg_t) + new_size;
 992             msg = pcmk__realloc(msg, msg->header.size);
 993             memcpy(msg->data, compressed, new_size);
 994 
 995             msg->is_compressed = TRUE;
 996             msg->compressed_size = new_size;
 997 
 998         } else {
 999             msg = pcmk__realloc(msg, msg->header.size);
1000             memcpy(msg->data, data, msg->size);
1001         }
1002 
1003         free(compressed);
1004     }
1005 
1006     iov = pcmk__assert_alloc(1, sizeof(struct iovec));
1007     iov->iov_base = msg;
1008     iov->iov_len = msg->header.size;
1009 
1010     if (msg->compressed_size > 0) {
1011         crm_trace("Queueing CPG message %" PRIu32 " to %s "
1012                   "(%zu bytes, %" PRIu32 " bytes compressed payload): %.200s",
1013                   msg->id, target, iov->iov_len, msg->compressed_size, data);
1014     } else {
1015         crm_trace("Queueing CPG message %" PRIu32 " to %s "
1016                   "(%zu bytes, %" PRIu32 " bytes payload): %.200s",
1017                   msg->id, target, iov->iov_len, msg->size, data);
1018     }
1019 
1020     free(target);
1021 
1022     cs_message_queue = g_list_append(cs_message_queue, iov);
1023     crm_cs_flush(&pcmk_cpg_handle);
1024 
1025     return true;
1026 }
1027 
1028 /*!
1029  * \internal
1030  * \brief Send an XML message via Corosync CPG
1031  *
1032  * \param[in] msg   XML message to send
1033  * \param[in] node  Cluster node to send message to
1034  * \param[in] dest  Type of message to send
1035  *
1036  * \return TRUE on success, otherwise FALSE
1037  */
1038 bool
1039 pcmk__cpg_send_xml(const xmlNode *msg, const pcmk__node_status_t *node,
     /*  */
1040                    enum pcmk_ipc_server dest)
1041 {
1042     bool rc = true;
1043     GString *data = g_string_sized_new(1024);
1044 
1045     pcmk__xml_string(msg, 0, data, 0);
1046 
1047     rc = send_cpg_text(data->str, node, dest);
1048     g_string_free(data, TRUE);
1049     return rc;
1050 }

/* */