daemons/fenced/fenced

/* */
This source file includes following definitions.
stonith_send_broadcast_history
stonith_remove_history_entry
stonith_fence_history_cleanup
op_time_sort
stonith_fence_history_trim
stonith_xml_history_to_list
stonith_local_history_diff_and_merge
stonith_local_history
stonith_fence_history
   1 /*
   2  * Copyright 2009-2021 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 General Public License version 2
   7  * or later (GPLv2+) WITHOUT ANY WARRANTY.
   8  */
   9 
  10 #include <crm_internal.h>
  11 
  12 #include <stdio.h>
  13 #include <unistd.h>
  14 #include <stdlib.h>
  15 
  16 #include <crm/crm.h>
  17 #include <crm/msg_xml.h>
  18 #include <crm/common/ipc.h>
  19 #include <crm/common/ipc_internal.h>
  20 #include <crm/cluster/internal.h>
  21 
  22 #include <crm/stonith-ng.h>
  23 #include <crm/fencing/internal.h>
  24 #include <crm/common/xml.h>
  25 #include <crm/common/xml_internal.h>
  26 
  27 #include <pacemaker-fenced.h>
  28 
  29 #define MAX_STONITH_HISTORY 500
  30 
  31 /*!
  32  * \internal
  33  * \brief Send a broadcast to all nodes to trigger cleanup or
  34  *        history synchronisation
  35  *
  36  * \param[in] history   Optional history to be attached
  37  * \param[in] callopts  We control cleanup via a flag in the callopts
  38  * \param[in] target    Cleanup can be limited to certain fence-targets
  39  */
  40 static void
  41 stonith_send_broadcast_history(xmlNode *history,
     /*  */
  42                                int callopts,
  43                                const char *target)
  44 {
  45     xmlNode *bcast = create_xml_node(NULL, "stonith_command");
  46     xmlNode *data = create_xml_node(NULL, __func__);
  47 
  48     if (target) {
  49         crm_xml_add(data, F_STONITH_TARGET, target);
  50     }
  51     crm_xml_add(bcast, F_TYPE, T_STONITH_NG);
  52     crm_xml_add(bcast, F_SUBTYPE, "broadcast");
  53     crm_xml_add(bcast, F_STONITH_OPERATION, STONITH_OP_FENCE_HISTORY);
  54     crm_xml_add_int(bcast, F_STONITH_CALLOPTS, callopts);
  55     if (history) {
  56         add_node_copy(data, history);
  57     }
  58     add_message_xml(bcast, F_STONITH_CALLDATA, data);
  59     send_cluster_message(NULL, crm_msg_stonith_ng, bcast, FALSE);
  60 
  61     free_xml(data);
  62     free_xml(bcast);
  63 }
  64 
  65 static gboolean
  66 stonith_remove_history_entry (gpointer key,
     /*  */
  67                               gpointer value,
  68                               gpointer user_data)
  69 {
  70     remote_fencing_op_t *op = value;
  71     const char *target = (const char *) user_data;
  72 
  73     if ((op->state == st_failed) || (op->state == st_done)) {
  74         if ((target) && (strcmp(op->target, target) != 0)) {
  75             return FALSE;
  76         }
  77         return TRUE;
  78     }
  79 
  80     return FALSE; /* don't clean pending operations */
  81 }
  82 
  83 /*!
  84  * \internal
  85  * \brief Send out a cleanup broadcast or do a local history-cleanup
  86  *
  87  * \param[in] target    Cleanup can be limited to certain fence-targets
  88  * \param[in] broadcast Send out a cleanup broadcast
  89  */
  90 static void
  91 stonith_fence_history_cleanup(const char *target,
     /*  */
  92                               gboolean broadcast)
  93 {
  94     if (broadcast) {
  95         stonith_send_broadcast_history(NULL,
  96                                        st_opt_cleanup | st_opt_discard_reply,
  97                                        target);
  98         /* we'll do the local clean when we receive back our own broadcast */
  99     } else if (stonith_remote_op_list) {
 100         g_hash_table_foreach_remove(stonith_remote_op_list,
 101                              stonith_remove_history_entry,
 102                              (gpointer) target);
 103         do_stonith_notify(0, T_STONITH_NOTIFY_HISTORY, 0, NULL);
 104     }
 105 }
 106 
 107 /* keeping the length of fence-history within bounds
 108  * =================================================
 109  *
 110  * If things are really running wild a lot of fencing-attempts
 111  * might fill up the hash-map, eventually using up a lot
 112  * of memory and creating huge history-sync messages.
 113  * Before the history being synced across nodes at least
 114  * the reboot of a cluster-node helped keeping the
 115  * history within bounds even though not in a reliable
 116  * manner.
 117  *
 118  * stonith_remote_op_list isn't sorted for time-stamps
 119  * thus it would be kind of expensive to delete e.g.
 120  * the oldest entry if it would grow past MAX_STONITH_HISTORY
 121  * entries.
 122  * It is more efficient to purge MAX_STONITH_HISTORY/2
 123  * entries whenever the list grows beyond MAX_STONITH_HISTORY.
 124  * (sort for age + purge the MAX_STONITH_HISTORY/2 oldest)
 125  * That done on a per-node-base might raise the
 126  * probability of large syncs to occur.
 127  * Things like introducing a broadcast to purge
 128  * MAX_STONITH_HISTORY/2 entries or not sync above a certain
 129  * threshold coming to mind ...
 130  * Simplest thing though is to purge the full history
 131  * throughout the cluster once MAX_STONITH_HISTORY is reached.
 132  * On the other hand this leads to purging the history in
 133  * situations where it would be handy to have it probably.
 134  */
 135 
 136 
 137 static int
 138 op_time_sort(const void *a_voidp, const void *b_voidp)
     /*  */
 139 {
 140     const remote_fencing_op_t **a = (const remote_fencing_op_t **) a_voidp;
 141     const remote_fencing_op_t **b = (const remote_fencing_op_t **) b_voidp;
 142     gboolean a_pending = ((*a)->state != st_failed) && ((*a)->state != st_done);
 143     gboolean b_pending = ((*b)->state != st_failed) && ((*b)->state != st_done);
 144 
 145     if (a_pending && b_pending) {
 146         return 0;
 147     } else if (a_pending) {
 148         return -1;
 149     } else if (b_pending) {
 150         return 1;
 151     } else if ((*b)->completed == (*a)->completed) {
 152         if ((*b)->completed_nsec > (*a)->completed_nsec) {
 153             return 1;
 154         } else if ((*b)->completed_nsec == (*a)->completed_nsec) {
 155             return 0;
 156         }
 157     } else if ((*b)->completed > (*a)->completed) {
 158         return 1;
 159     }
 160 
 161     return -1;
 162 }
 163 
 164 
 165 /*!
 166  * \internal
 167  * \brief Do a local history-trim to MAX_STONITH_HISTORY / 2 entries
 168  *        once over MAX_STONITH_HISTORY
 169  */
 170 void
 171 stonith_fence_history_trim(void)
     /*  */
 172 {
 173     guint num_ops;
 174 
 175     if (!stonith_remote_op_list) {
 176         return;
 177     }
 178     num_ops = g_hash_table_size(stonith_remote_op_list);
 179     if (num_ops > MAX_STONITH_HISTORY) {
 180         remote_fencing_op_t *ops[num_ops];
 181         remote_fencing_op_t *op = NULL;
 182         GHashTableIter iter;
 183         int i;
 184 
 185         crm_trace("Fencing History growing beyond limit of %d so purge "
 186                   "half of failed/successful attempts", MAX_STONITH_HISTORY);
 187 
 188         /* write all ops into an array */
 189         i = 0;
 190         g_hash_table_iter_init(&iter, stonith_remote_op_list);
 191         while (g_hash_table_iter_next(&iter, NULL, (void **)&op)) {
 192             ops[i++] = op;
 193         }
 194         /* run quicksort over the array so that we get pending ops
 195          * first and then sorted most recent to oldest
 196          */
 197         qsort(ops, num_ops, sizeof(remote_fencing_op_t *), op_time_sort);
 198         /* purgest oldest half of the history entries */
 199         for (i = MAX_STONITH_HISTORY / 2; i < num_ops; i++) {
 200             /* keep pending ops even if they shouldn't fill more than
 201              * half of our buffer
 202              */
 203             if ((ops[i]->state == st_failed) || (ops[i]->state == st_done)) {
 204                 g_hash_table_remove(stonith_remote_op_list, ops[i]->id);
 205             }
 206         }
 207         /* we've just purged valid data from the list so there is no need
 208          * to create a notification - if displayed it can stay
 209          */
 210     }
 211 }
 212 
 213 /*!
 214  * \internal
 215  * \brief Convert xml fence-history to a hash-table like stonith_remote_op_list
 216  *
 217  * \param[in] history   Fence-history in xml
 218  *
 219  * \return Fence-history as hash-table
 220  */
 221 static GHashTable *
 222 stonith_xml_history_to_list(xmlNode *history)
     /*  */
 223 {
 224     xmlNode *xml_op = NULL;
 225     GHashTable *rv = NULL;
 226 
 227     init_stonith_remote_op_hash_table(&rv);
 228 
 229     CRM_LOG_ASSERT(rv != NULL);
 230 
 231     for (xml_op = pcmk__xml_first_child(history); xml_op != NULL;
 232          xml_op = pcmk__xml_next(xml_op)) {
 233         remote_fencing_op_t *op = NULL;
 234         char *id = crm_element_value_copy(xml_op, F_STONITH_REMOTE_OP_ID);
 235         int state;
 236         long long completed;
 237         long long completed_nsec = 0L;
 238 
 239         if (!id) {
 240             crm_warn("Malformed fencing history received from peer");
 241             continue;
 242         }
 243 
 244         crm_trace("Attaching op %s to hashtable", id);
 245 
 246         op = calloc(1, sizeof(remote_fencing_op_t));
 247 
 248         op->id = id;
 249         op->target = crm_element_value_copy(xml_op, F_STONITH_TARGET);
 250         op->action = crm_element_value_copy(xml_op, F_STONITH_ACTION);
 251         op->originator = crm_element_value_copy(xml_op, F_STONITH_ORIGIN);
 252         op->delegate = crm_element_value_copy(xml_op, F_STONITH_DELEGATE);
 253         op->client_name = crm_element_value_copy(xml_op, F_STONITH_CLIENTNAME);
 254         crm_element_value_ll(xml_op, F_STONITH_DATE, &completed);
 255         op->completed = (time_t) completed;
 256         crm_element_value_ll(xml_op, F_STONITH_DATE_NSEC, &completed_nsec);
 257         op->completed_nsec = completed_nsec;
 258         crm_element_value_int(xml_op, F_STONITH_STATE, &state);
 259         op->state = (enum op_state) state;
 260 
 261         g_hash_table_replace(rv, id, op);
 262         CRM_LOG_ASSERT(g_hash_table_lookup(rv, id) != NULL);
 263     }
 264 
 265     return rv;
 266 }
 267 
 268 /*!
 269  * \internal
 270  * \brief Craft xml difference between local fence-history and a history
 271  *        coming from remote, and merge the remote history into the local
 272  *
 273  * \param[in] remote_history    Fence-history as hash-table (may be NULL)
 274  * \param[in] add_id            If crafting the answer for an API
 275  *                              history-request there is no need for the id
 276  * \param[in] target            Optionally limit to certain fence-target
 277  *
 278  * \return The fence-history as xml
 279  */
 280 static xmlNode *
 281 stonith_local_history_diff_and_merge(GHashTable *remote_history,
     /*  */
 282                            gboolean add_id,
 283                            const char *target)
 284 {
 285     xmlNode *history = NULL;
 286     GHashTableIter iter;
 287     remote_fencing_op_t *op = NULL;
 288     gboolean updated = FALSE;
 289     int cnt = 0;
 290 
 291     if (stonith_remote_op_list) {
 292             char *id = NULL;
 293 
 294             history = create_xml_node(NULL, F_STONITH_HISTORY_LIST);
 295 
 296             g_hash_table_iter_init(&iter, stonith_remote_op_list);
 297             while (g_hash_table_iter_next(&iter, (void **)&id, (void **)&op)) {
 298                 xmlNode *entry = NULL;
 299 
 300                 if (remote_history) {
 301                     remote_fencing_op_t *remote_op =
 302                         g_hash_table_lookup(remote_history, op->id);
 303 
 304                     if (remote_op) {
 305                         if (stonith__op_state_pending(op->state)
 306                             && !stonith__op_state_pending(remote_op->state)) {
 307 
 308                             crm_debug("Updating outdated pending operation %.8s "
 309                                       "(state=%s) according to the one (state=%s) from "
 310                                       "remote peer history",
 311                                       op->id, stonith_op_state_str(op->state),
 312                                       stonith_op_state_str(remote_op->state));
 313 
 314                             g_hash_table_steal(remote_history, op->id);
 315                             op->id = remote_op->id;
 316                             remote_op->id = id;
 317                             g_hash_table_iter_replace(&iter, remote_op);
 318 
 319                             updated = TRUE;
 320                             continue; /* skip outdated entries */
 321 
 322                         } else if (!stonith__op_state_pending(op->state)
 323                                    && stonith__op_state_pending(remote_op->state)) {
 324 
 325                             crm_debug("Broadcasting operation %.8s (state=%s) to "
 326                                       "update the outdated pending one "
 327                                       "(state=%s) in remote peer history",
 328                                       op->id, stonith_op_state_str(op->state),
 329                                       stonith_op_state_str(remote_op->state));
 330 
 331                             g_hash_table_remove(remote_history, op->id);
 332 
 333                         } else {
 334                             g_hash_table_remove(remote_history, op->id);
 335                             continue; /* skip entries broadcasted already */
 336                         }
 337                     }
 338                 }
 339 
 340                 if (!pcmk__str_eq(target, op->target, pcmk__str_null_matches)) {
 341                     continue;
 342                 }
 343 
 344                 cnt++;
 345                 crm_trace("Attaching op %s", op->id);
 346                 entry = create_xml_node(history, STONITH_OP_EXEC);
 347                 if (add_id) {
 348                     crm_xml_add(entry, F_STONITH_REMOTE_OP_ID, op->id);
 349                 }
 350                 crm_xml_add(entry, F_STONITH_TARGET, op->target);
 351                 crm_xml_add(entry, F_STONITH_ACTION, op->action);
 352                 crm_xml_add(entry, F_STONITH_ORIGIN, op->originator);
 353                 crm_xml_add(entry, F_STONITH_DELEGATE, op->delegate);
 354                 crm_xml_add(entry, F_STONITH_CLIENTNAME, op->client_name);
 355                 crm_xml_add_ll(entry, F_STONITH_DATE, op->completed);
 356                 crm_xml_add_ll(entry, F_STONITH_DATE_NSEC, op->completed_nsec);
 357                 crm_xml_add_int(entry, F_STONITH_STATE, op->state);
 358             }
 359     }
 360 
 361     if (remote_history) {
 362         init_stonith_remote_op_hash_table(&stonith_remote_op_list);
 363 
 364         updated |= g_hash_table_size(remote_history);
 365 
 366         g_hash_table_iter_init(&iter, remote_history);
 367         while (g_hash_table_iter_next(&iter, NULL, (void **)&op)) {
 368 
 369             if (stonith__op_state_pending(op->state) &&
 370                 pcmk__str_eq(op->originator, stonith_our_uname, pcmk__str_casei)) {
 371                 crm_warn("Failing pending operation %.8s originated by us but "
 372                          "known only from peer history", op->id);
 373                 op->state = st_failed;
 374                 set_fencing_completed(op);
 375                 /* use -EHOSTUNREACH to not introduce a new return-code that might
 376                    trigger unexpected results at other places and to prevent
 377                    remote_op_done from setting the delegate if not present
 378                 */
 379                 stonith_bcast_result_to_peers(op, -EHOSTUNREACH, FALSE);
 380             }
 381 
 382             g_hash_table_iter_steal(&iter);
 383             g_hash_table_replace(stonith_remote_op_list, op->id, op);
 384             /* we could trim the history here but if we bail
 385              * out after trim we might miss more recent entries
 386              * of those that might still be in the list
 387              * if we don't bail out trimming once is more
 388              * efficient and memory overhead is minimal as
 389              * we are just moving pointers from one hash to
 390              * another
 391              */
 392         }
 393 
 394         g_hash_table_destroy(remote_history); /* remove what is left */
 395     }
 396 
 397     if (updated) {
 398         stonith_fence_history_trim();
 399         do_stonith_notify(0, T_STONITH_NOTIFY_HISTORY, 0, NULL);
 400     }
 401 
 402     if (cnt == 0) {
 403         free_xml(history);
 404         return NULL;
 405     } else {
 406         return history;
 407     }
 408 }
 409 
 410 /*!
 411  * \internal
 412  * \brief Craft xml from the local fence-history
 413  *
 414  * \param[in] add_id            If crafting the answer for an API
 415  *                              history-request there is no need for the id
 416  * \param[in] target            Optionally limit to certain fence-target
 417  *
 418  * \return The fence-history as xml
 419  */
 420 static xmlNode *
 421 stonith_local_history(gboolean add_id, const char *target)
     /*  */
 422 {
 423     return stonith_local_history_diff_and_merge(NULL, add_id, target);
 424 }
 425 
 426 /*!
 427  * \internal
 428  * \brief Handle fence-history messages (either from API or coming in as
 429  *        broadcasts
 430  *
 431  * \param[in] msg       Request message
 432  * \param[in] output    In case of a request from the API used to craft
 433  *                      a reply from
 434  * \param[in] remote_peer
 435  * \param[in] options   call-options from the request
 436  *
 437  * \return always success as there is actully nothing that can go really wrong
 438  */
 439 int
 440 stonith_fence_history(xmlNode *msg, xmlNode **output,
     /*  */
 441                       const char *remote_peer, int options)
 442 {
 443     int rc = 0;
 444     const char *target = NULL;
 445     xmlNode *dev = get_xpath_object("//@" F_STONITH_TARGET, msg, LOG_NEVER);
 446     xmlNode *out_history = NULL;
 447 
 448     if (dev) {
 449         target = crm_element_value(dev, F_STONITH_TARGET);
 450         if (target && (options & st_opt_cs_nodeid)) {
 451             int nodeid;
 452             crm_node_t *node;
 453 
 454             pcmk__scan_min_int(target, &nodeid, 0);
 455             node = pcmk__search_known_node_cache(nodeid, NULL, CRM_GET_PEER_ANY);
 456             if (node) {
 457                 target = node->uname;
 458             }
 459         }
 460     }
 461 
 462     if (options & st_opt_cleanup) {
 463         crm_trace("Cleaning up operations on %s in %p", target,
 464                   stonith_remote_op_list);
 465 
 466         stonith_fence_history_cleanup(target,
 467             crm_element_value(msg, F_STONITH_CALLID) != NULL);
 468     } else if (options & st_opt_broadcast) {
 469         /* there is no clear sign atm for when a history sync
 470            is done so send a notification for anything
 471            that smells like history-sync
 472          */
 473         do_stonith_notify(0, T_STONITH_NOTIFY_HISTORY_SYNCED, 0, NULL);
 474         if (crm_element_value(msg, F_STONITH_CALLID)) {
 475             /* this is coming from the stonith-API
 476             *
 477             * craft a broadcast with node's history
 478             * so that every node can merge and broadcast
 479             * what it has on top
 480             */
 481             out_history = stonith_local_history(TRUE, NULL);
 482             crm_trace("Broadcasting history to peers");
 483             stonith_send_broadcast_history(out_history,
 484                                         st_opt_broadcast | st_opt_discard_reply,
 485                                         NULL);
 486         } else if (remote_peer &&
 487                    !pcmk__str_eq(remote_peer, stonith_our_uname, pcmk__str_casei)) {
 488             xmlNode *history = get_xpath_object("//" F_STONITH_HISTORY_LIST,
 489                                                 msg, LOG_NEVER);
 490             GHashTable *received_history =
 491                 history?stonith_xml_history_to_list(history):NULL;
 492 
 493             /* either a broadcast created directly upon stonith-API request
 494             * or a diff as response to such a thing
 495             *
 496             * in both cases it may have a history or not
 497             * if we have differential data
 498             * merge in what we've received and stop
 499             * otherwise broadcast what we have on top
 500             * marking as differential and merge in afterwards
 501             */
 502             if (!history ||
 503                 !crm_is_true(crm_element_value(history,
 504                                                F_STONITH_DIFFERENTIAL))) {
 505                 out_history =
 506                     stonith_local_history_diff_and_merge(received_history, TRUE, NULL);
 507                 if (out_history) {
 508                     crm_trace("Broadcasting history-diff to peers");
 509                     crm_xml_add(out_history, F_STONITH_DIFFERENTIAL,
 510                                 XML_BOOLEAN_TRUE);
 511                     stonith_send_broadcast_history(out_history,
 512                         st_opt_broadcast | st_opt_discard_reply,
 513                         NULL);
 514                 } else {
 515                     crm_trace("History-diff is empty - skip broadcast");
 516                 }
 517             }
 518         } else {
 519             crm_trace("Skipping history-query-broadcast (%s%s)"
 520                       " we sent ourselves",
 521                       remote_peer?"remote-peer=":"local-ipc",
 522                       remote_peer?remote_peer:"");
 523         }
 524     } else {
 525         /* plain history request */
 526         crm_trace("Looking for operations on %s in %p", target,
 527                   stonith_remote_op_list);
 528         *output = stonith_local_history(FALSE, target);
 529     }
 530     free_xml(out_history);
 531     return rc;
 532 }
/* */
root/daemons/fenced/fenced_history.c

DEFINITIONS
