source/lib/ctdbd_conn.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Samba internal messaging functions
   4    Copyright (C) 2007 by Volker Lendecke
   5    Copyright (C) 2007 by Andrew Tridgell
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 #ifdef CLUSTER_SUPPORT
  25
  26 #include "librpc/gen_ndr/messaging.h"
  27 #include "librpc/gen_ndr/ndr_messaging.h"
  28
  29 /* paths to these include files come from --with-ctdb= in configure */
  30 #include "ctdb.h"
  31 #include "ctdb_private.h"
  32
  33 struct ctdbd_connection {
  34         struct messaging_context *msg_ctx;
  35         uint32 reqid;
  36         uint32 our_vnn;
  37         uint64 rand_srvid;
  38         struct packet_context *pkt;
  39         struct fd_event *fde;
  40
  41         void (*release_ip_handler)(const char *ip_addr, void *private_data);
  42         void *release_ip_priv;
  43 };
  44
  45 static NTSTATUS ctdbd_control(struct ctdbd_connection *conn,
  46                               uint32_t vnn, uint32 opcode,
  47                               uint64_t srvid, TDB_DATA data,
  48                               TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
  49                               int *cstatus);
  50
  51 /*
  52  * exit on fatal communications errors with the ctdbd daemon
  53  */
  54 static void cluster_fatal(const char *why)
  55 {
  56         DEBUG(0,("cluster fatal event: %s - exiting immediately\n", why));
  57         /* we don't use smb_panic() as we don't want to delay to write
  58            a core file. We need to release this process id immediately
  59            so that someone else can take over without getting sharing
  60            violations */
  61         _exit(0);
  62 }
  63
  64 /*
  65  * Register a srvid with ctdbd
  66  */
  67 static NTSTATUS register_with_ctdbd(struct ctdbd_connection *conn,
  68                                     uint64_t srvid)
  69 {
  70
  71         int cstatus;
  72         return ctdbd_control(conn, CTDB_CURRENT_NODE,
  73                              CTDB_CONTROL_REGISTER_SRVID, srvid,
  74                              tdb_null, NULL, NULL, &cstatus);
  75 }
  76
  77 /*
  78  * get our vnn from the cluster
  79  */
  80 static NTSTATUS get_cluster_vnn(struct ctdbd_connection *conn, uint32 *vnn)
  81 {
  82         int32_t cstatus=-1;
  83         NTSTATUS status;
  84         status = ctdbd_control(conn,
  85                                CTDB_CURRENT_NODE, CTDB_CONTROL_GET_VNN, 0,
  86                                tdb_null, NULL, NULL, &cstatus);
  87         if (!NT_STATUS_IS_OK(status)) {
  88                 cluster_fatal("ctdbd_control failed\n");
  89         }
  90         *vnn = (uint32_t)cstatus;
  91         return status;
  92 }
  93
  94 uint32 ctdbd_vnn(const struct ctdbd_connection *conn)
  95 {
  96         return conn->our_vnn;
  97 }
  98
  99 /*
 100  * Get us a ctdb connection
 101  */
 102
 103 static NTSTATUS ctdbd_connect(TALLOC_CTX *mem_ctx,
 104                               struct packet_context **presult)
 105 {
 106         struct packet_context *result;
 107         const char *sockname = lp_ctdbd_socket();
 108         struct sockaddr_un addr;
 109         int fd;
 110
 111         if (!sockname || !*sockname) {
 112                 sockname = CTDB_PATH;
 113         }
 114
 115         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 116         if (fd == -1) {
 117                 DEBUG(3, ("Could not create socket: %s\n", strerror(errno)));
 118                 return map_nt_error_from_unix(errno);
 119         }
 120
 121         ZERO_STRUCT(addr);
 122         addr.sun_family = AF_UNIX;
 123         strncpy(addr.sun_path, sockname, sizeof(addr.sun_path));
 124
 125         if (connect(fd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
 126                 DEBUG(0, ("connect(%s) failed: %s\n", sockname,
 127                           strerror(errno)));
 128                 close(fd);
 129                 return map_nt_error_from_unix(errno);
 130         }
 131
 132         if (!(result = packet_init(mem_ctx, fd))) {
 133                 close(fd);
 134                 return NT_STATUS_NO_MEMORY;
 135         }
 136
 137         *presult = result;
 138         return NT_STATUS_OK;
 139 }
 140
 141 /*
 142  * Do we have a complete ctdb packet in the queue?
 143  */
 144
 145 static BOOL ctdb_req_complete(const struct data_blob *data,
 146                               size_t *length,
 147                               void *private_data)
 148 {
 149         uint32 msglen;
 150
 151         if (data->length < sizeof(msglen)) {
 152                 return False;
 153         }
 154
 155         msglen = *((uint32 *)data->data);
 156
 157         DEBUG(10, ("msglen = %d\n", msglen));
 158
 159         if (msglen < sizeof(struct ctdb_req_header)) {
 160                 DEBUG(0, ("Got invalid msglen: %d, expected at least %d for "
 161                           "the req_header\n", msglen,
 162                           sizeof(struct ctdb_req_header)));
 163                 cluster_fatal("ctdbd protocol error\n");
 164         }
 165
 166         if (data->length >= msglen) {
 167                 *length = msglen;
 168                 return True;
 169         }
 170
 171         return False;
 172 }
 173
 174 /*
 175  * State necessary to defer an incoming message while we are waiting for a
 176  * ctdb reply.
 177  */
 178
 179 struct deferred_msg_state {
 180         struct messaging_context *msg_ctx;
 181         struct messaging_rec *rec;
 182 };
 183
 184 /*
 185  * Timed event handler for the deferred message
 186  */
 187
 188 static void deferred_message_dispatch(struct event_context *event_ctx,
 189                                       struct timed_event *te,
 190                                       const struct timeval *now,
 191                                       void *private_data)
 192 {
 193         struct deferred_msg_state *state = talloc_get_type_abort(
 194                 private_data, struct deferred_msg_state);
 195
 196         messaging_dispatch_rec(state->msg_ctx, state->rec);
 197         TALLOC_FREE(state);
 198         TALLOC_FREE(te);
 199 }
 200
 201 struct req_pull_state {
 202         TALLOC_CTX *mem_ctx;
 203         DATA_BLOB req;
 204 };
 205
 206 /*
 207  * Pull a ctdb request out of the incoming packet queue
 208  */
 209
 210 static NTSTATUS ctdb_req_pull(const struct data_blob *data,
 211                               void *private_data)
 212 {
 213         struct req_pull_state *state = (struct req_pull_state *)private_data;
 214
 215         state->req = data_blob_talloc(state->mem_ctx, data->data,
 216                                       data->length);
 217         if (state->req.data == NULL) {
 218                 return NT_STATUS_NO_MEMORY;
 219         }
 220         return NT_STATUS_OK;
 221 }
 222
 223 /*
 224  * Fetch a messaging_rec from an incoming ctdb style message
 225  */
 226
 227 static struct messaging_rec *ctdb_pull_messaging_rec(TALLOC_CTX *mem_ctx,
 228                                                      size_t overall_length,
 229                                                      struct ctdb_req_message *msg)
 230 {
 231         struct messaging_rec *result;
 232         DATA_BLOB blob;
 233         NTSTATUS status;
 234
 235         if ((overall_length < offsetof(struct ctdb_req_message, data))
 236             || (overall_length
 237                 < offsetof(struct ctdb_req_message, data) + msg->datalen)) {
 238
 239                 cluster_fatal("got invalid msg length");
 240         }
 241
 242         if (!(result = TALLOC_P(mem_ctx, struct messaging_rec))) {
 243                 DEBUG(0, ("talloc failed\n"));
 244                 return NULL;
 245         }
 246
 247         blob = data_blob_const(msg->data, msg->datalen);
 248
 249         status = ndr_pull_struct_blob(
 250                 &blob, result, result,
 251                 (ndr_pull_flags_fn_t)ndr_pull_messaging_rec);
 252
 253         if (!NT_STATUS_IS_OK(status)) {
 254                 DEBUG(0, ("ndr_pull_struct_blob failed: %s\n",
 255                           nt_errstr(status)));
 256                 TALLOC_FREE(result);
 257                 return NULL;
 258         }
 259
 260         return result;
 261 }
 262
 263 /*
 264  * Read a full ctdbd request. If we have a messaging context, defer incoming
 265  * messages that might come in between.
 266  */
 267
 268 static NTSTATUS ctdb_read_req(struct ctdbd_connection *conn, uint32 reqid,
 269                               TALLOC_CTX *mem_ctx, void *result)
 270 {
 271         struct ctdb_req_header *hdr;
 272         struct req_pull_state state;
 273         NTSTATUS status;
 274
 275  again:
 276
 277         status = packet_fd_read_sync(conn->pkt);
 278
 279         if (NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_BUSY)) {
 280                 /* EAGAIN */
 281                 goto again;
 282         }
 283
 284         if (!NT_STATUS_IS_OK(status)) {
 285                 DEBUG(3, ("packet_fd_read failed: %s\n", nt_errstr(status)));
 286                 cluster_fatal("ctdbd died\n");
 287         }
 288
 289         ZERO_STRUCT(state);
 290         state.mem_ctx = mem_ctx;
 291
 292         if (!packet_handler(conn->pkt, ctdb_req_complete, ctdb_req_pull,
 293                             &state, &status)) {
 294                 /*
 295                  * Not enough data
 296                  */
 297                 goto again;
 298         }
 299
 300         if (!NT_STATUS_IS_OK(status)) {
 301                 DEBUG(3, ("Could not read packet: %s\n", nt_errstr(status)));
 302                 cluster_fatal("ctdbd died\n");
 303         }
 304
 305         hdr = (struct ctdb_req_header *)state.req.data;
 306
 307         if (hdr->operation == CTDB_REQ_MESSAGE) {
 308                 struct timed_event *evt;
 309                 struct deferred_msg_state *msg_state;
 310                 struct ctdb_req_message *msg = (struct ctdb_req_message *)hdr;
 311
 312                 if (conn->msg_ctx == NULL) {
 313                         DEBUG(1, ("Got a message without having a msg ctx, "
 314                                   "dropping msg %llu\n", msg->srvid));
 315                         goto again;
 316                 }
 317
 318                 if ((conn->release_ip_handler != NULL)
 319                     && (msg->srvid == CTDB_SRVID_RELEASE_IP)) {
 320                         /* must be dispatched immediately */
 321                         DEBUG(10, ("received CTDB_SRVID_RELEASE_IP\n"));
 322                         conn->release_ip_handler((const char *)msg->data,
 323                                                  conn->release_ip_priv);
 324                         TALLOC_FREE(hdr);
 325                         goto again;
 326                 }
 327
 328                 if (!(msg_state = TALLOC_P(NULL, struct deferred_msg_state))) {
 329                         DEBUG(0, ("talloc failed\n"));
 330                         TALLOC_FREE(hdr);
 331                         goto again;
 332                 }
 333
 334                 if (!(msg_state->rec = ctdb_pull_messaging_rec(
 335                               msg_state, state.req.length, msg))) {
 336                         DEBUG(0, ("ctdbd_pull_messaging_rec failed\n"));
 337                         TALLOC_FREE(msg_state);
 338                         TALLOC_FREE(hdr);
 339                         goto again;
 340                 }
 341
 342                 TALLOC_FREE(hdr);
 343
 344                 msg_state->msg_ctx = conn->msg_ctx;
 345
 346                 /*
 347                  * We're waiting for a call reply, but an async message has
 348                  * crossed. Defer dispatching to the toplevel event loop.
 349                  */
 350                 evt = event_add_timed(conn->msg_ctx->event_ctx,
 351                                       conn->msg_ctx->event_ctx,
 352                                       timeval_zero(),
 353                                       "deferred_message_dispatch",
 354                                       deferred_message_dispatch,
 355                                       msg_state);
 356                 if (evt == NULL) {
 357                         DEBUG(0, ("event_add_timed failed\n"));
 358                         TALLOC_FREE(msg_state);
 359                         TALLOC_FREE(hdr);
 360                         goto again;
 361                 }
 362
 363                 goto again;
 364         }
 365
 366         if (hdr->reqid != reqid) {
 367                 /* we got the wrong reply */
 368                 DEBUG(0,("Discarding mismatched ctdb reqid %u should have "
 369                          "been %u\n", hdr->reqid, reqid));
 370                 TALLOC_FREE(hdr);
 371                 goto again;
 372         }
 373
 374         *((void **)result) = talloc_move(mem_ctx, &hdr);
 375
 376         return NT_STATUS_OK;
 377 }
 378
 379 /*
 380  * Get us a ctdbd connection
 381  */
 382
 383 NTSTATUS ctdbd_init_connection(TALLOC_CTX *mem_ctx,
 384                                struct ctdbd_connection **pconn)
 385 {
 386         struct ctdbd_connection *conn;
 387         NTSTATUS status;
 388
 389         if (!(conn = TALLOC_ZERO_P(mem_ctx, struct ctdbd_connection))) {
 390                 DEBUG(0, ("talloc failed\n"));
 391                 return NT_STATUS_NO_MEMORY;
 392         }
 393
 394         status = ctdbd_connect(conn, &conn->pkt);
 395
 396         if (!NT_STATUS_IS_OK(status)) {
 397                 DEBUG(10, ("ctdbd_connect failed: %s\n", nt_errstr(status)));
 398                 goto fail;
 399         }
 400
 401         status = get_cluster_vnn(conn, &conn->our_vnn);
 402
 403         if (!NT_STATUS_IS_OK(status)) {
 404                 DEBUG(10, ("get_cluster_vnn failed: %s\n", nt_errstr(status)));
 405                 goto fail;
 406         }
 407
 408         generate_random_buffer((unsigned char *)&conn->rand_srvid,
 409                                sizeof(conn->rand_srvid));
 410
 411         status = register_with_ctdbd(conn, conn->rand_srvid);
 412
 413         if (!NT_STATUS_IS_OK(status)) {
 414                 DEBUG(5, ("Could not register random srvid: %s\n",
 415                           nt_errstr(status)));
 416                 goto fail;
 417         }
 418
 419         *pconn = conn;
 420         return NT_STATUS_OK;
 421
 422  fail:
 423         TALLOC_FREE(conn);
 424         return status;
 425 }
 426
 427 /*
 428  * Get us a ctdbd connection and register us as a process
 429  */
 430
 431 NTSTATUS ctdbd_messaging_connection(TALLOC_CTX *mem_ctx,
 432                                     struct ctdbd_connection **pconn)
 433 {
 434         struct ctdbd_connection *conn;
 435         NTSTATUS status;
 436
 437         status = ctdbd_init_connection(mem_ctx, &conn);
 438
 439         if (!NT_STATUS_IS_OK(status)) {
 440                 return status;
 441         }
 442
 443         status = register_with_ctdbd(conn, (uint64_t)sys_getpid());
 444         if (!NT_STATUS_IS_OK(status)) {
 445                 goto fail;
 446         }
 447
 448         status = register_with_ctdbd(conn, MSG_SRVID_SAMBA);
 449         if (!NT_STATUS_IS_OK(status)) {
 450                 goto fail;
 451         }
 452
 453         *pconn = conn;
 454         return NT_STATUS_OK;
 455
 456  fail:
 457         TALLOC_FREE(conn);
 458         return status;
 459 }
 460
 461 /*
 462  * Packet handler to receive and handle a ctdb message
 463  */
 464 static NTSTATUS ctdb_handle_message(const struct data_blob *data,
 465                                     void *private_data)
 466 {
 467         struct ctdbd_connection *conn = talloc_get_type_abort(
 468                 private_data, struct ctdbd_connection);
 469         struct ctdb_req_message *msg;
 470         struct messaging_rec *msg_rec;
 471
 472         msg = (struct ctdb_req_message *)data->data;
 473
 474         if (msg->hdr.operation != CTDB_REQ_MESSAGE) {
 475                 DEBUG(0, ("Received async msg of type %u, discarding\n",
 476                           msg->hdr.operation));
 477                 return NT_STATUS_INVALID_PARAMETER;
 478         }
 479
 480         if ((conn->release_ip_handler != NULL)
 481             && (msg->srvid == CTDB_SRVID_RELEASE_IP)) {
 482                 /* must be dispatched immediately */
 483                 DEBUG(10, ("received CTDB_SRVID_RELEASE_IP\n"));
 484                 conn->release_ip_handler((const char *)msg->data,
 485                                          conn->release_ip_priv);
 486                 return NT_STATUS_OK;
 487         }
 488
 489         SMB_ASSERT(conn->msg_ctx != NULL);
 490
 491         if (msg->srvid == CTDB_SRVID_RECONFIGURE) {
 492                 DEBUG(0,("Got cluster reconfigure message\n"));
 493                 /*
 494                  * when the cluster is reconfigured, we need to clean the brl
 495                  * database
 496                  */
 497                 messaging_send(conn->msg_ctx, procid_self(),
 498                                MSG_SMB_BRL_VALIDATE, &data_blob_null);
 499
 500                 /*
 501                  * it's possible that we have just rejoined the cluster after
 502                  * an outage. In that case our pending locks could have been
 503                  * removed from the lockdb, so retry them once more
 504                  */
 505                 message_send_all(conn->msg_ctx, MSG_SMB_UNLOCK, NULL, 0, NULL);
 506
 507                 return NT_STATUS_OK;
 508
 509         }
 510
 511         /* only messages to our pid or the broadcast are valid here */
 512         if (msg->srvid != sys_getpid() && msg->srvid != MSG_SRVID_SAMBA) {
 513                 DEBUG(0,("Got unexpected message with srvid=%llu\n",
 514                          (unsigned long long)msg->srvid));
 515                 return NT_STATUS_OK;
 516         }
 517
 518         if (!(msg_rec = ctdb_pull_messaging_rec(NULL, data->length, msg))) {
 519                 DEBUG(10, ("ctdb_pull_messaging_rec failed\n"));
 520                 return NT_STATUS_NO_MEMORY;
 521         }
 522
 523         messaging_dispatch_rec(conn->msg_ctx, msg_rec);
 524
 525         TALLOC_FREE(msg_rec);
 526         return NT_STATUS_OK;
 527 }
 528
 529 /*
 530  * The ctdbd socket is readable asynchronuously
 531  */
 532
 533 static void ctdbd_socket_handler(struct event_context *event_ctx,
 534                                  struct fd_event *event,
 535                                  uint16 flags,
 536                                  void *private_data)
 537 {
 538         struct ctdbd_connection *conn = talloc_get_type_abort(
 539                 private_data, struct ctdbd_connection);
 540
 541         NTSTATUS status;
 542
 543         status = packet_fd_read(conn->pkt);
 544
 545         if (!NT_STATUS_IS_OK(status)) {
 546                 DEBUG(0, ("packet_fd_read failed: %s\n", nt_errstr(status)));
 547                 cluster_fatal("ctdbd died\n");
 548         }
 549
 550         while (packet_handler(conn->pkt, ctdb_req_complete,
 551                               ctdb_handle_message, conn, &status)) {
 552                 if (!NT_STATUS_IS_OK(status)) {
 553                         DEBUG(10, ("could not handle incoming message: %s\n",
 554                                    nt_errstr(status)));
 555                 }
 556         }
 557 }
 558
 559 /*
 560  * Prepare a ctdbd connection to receive messages
 561  */
 562
 563 NTSTATUS ctdbd_register_msg_ctx(struct ctdbd_connection *conn,
 564                                 struct messaging_context *msg_ctx)
 565 {
 566         SMB_ASSERT(conn->msg_ctx == NULL);
 567         SMB_ASSERT(conn->fde == NULL);
 568
 569         if (!(conn->fde = event_add_fd(msg_ctx->event_ctx, conn,
 570                                        packet_get_fd(conn->pkt),
 571                                        EVENT_FD_READ,
 572                                        ctdbd_socket_handler,
 573                                        conn))) {
 574                 DEBUG(0, ("event_add_fd failed\n"));
 575                 return NT_STATUS_NO_MEMORY;
 576         }
 577
 578         conn->msg_ctx = msg_ctx;
 579
 580         return NT_STATUS_OK;
 581 }
 582
 583 /*
 584  * Send a messaging message across a ctdbd
 585  */
 586
 587 NTSTATUS ctdbd_messaging_send(struct ctdbd_connection *conn,
 588                               uint32 dst_vnn, uint64 dst_srvid,
 589                               struct messaging_rec *msg)
 590 {
 591         struct ctdb_req_message r;
 592         TALLOC_CTX *mem_ctx;
 593         DATA_BLOB blob;
 594         NTSTATUS status;
 595
 596         if (!(mem_ctx = talloc_init("ctdbd_messaging_send"))) {
 597                 DEBUG(0, ("talloc failed\n"));
 598                 return NT_STATUS_NO_MEMORY;
 599         }
 600
 601         status = ndr_push_struct_blob(
 602                 &blob, mem_ctx, msg,
 603                 (ndr_push_flags_fn_t)ndr_push_messaging_rec);
 604
 605         if (!NT_STATUS_IS_OK(status)) {
 606                 DEBUG(0, ("ndr_push_struct_blob failed: %s\n",
 607                           nt_errstr(status)));
 608                 goto fail;
 609         }
 610
 611         r.hdr.length = offsetof(struct ctdb_req_message, data) + blob.length;
 612         r.hdr.ctdb_magic = CTDB_MAGIC;
 613         r.hdr.ctdb_version = CTDB_VERSION;
 614         r.hdr.generation = 1;
 615         r.hdr.operation  = CTDB_REQ_MESSAGE;
 616         r.hdr.destnode   = dst_vnn;
 617         r.hdr.srcnode    = conn->our_vnn;
 618         r.hdr.reqid      = 0;
 619         r.srvid          = dst_srvid;
 620         r.datalen        = blob.length;
 621
 622         status = packet_send(
 623                 conn->pkt, 2,
 624                 data_blob_const(&r, offsetof(struct ctdb_req_message, data)),
 625                 blob);
 626
 627         if (!NT_STATUS_IS_OK(status)) {
 628                 DEBUG(0, ("packet_send failed: %s\n", nt_errstr(status)));
 629                 goto fail;
 630         }
 631
 632         status = packet_flush(conn->pkt);
 633
 634         if (!NT_STATUS_IS_OK(status)) {
 635                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 636                 cluster_fatal("cluster dispatch daemon msg write error\n");
 637         }
 638
 639         status = NT_STATUS_OK;
 640  fail:
 641         TALLOC_FREE(mem_ctx);
 642         return status;
 643 }
 644
 645 /*
 646  * send/recv a generic ctdb control message
 647  */
 648 static NTSTATUS ctdbd_control(struct ctdbd_connection *conn,
 649                               uint32_t vnn, uint32 opcode,
 650                               uint64_t srvid, TDB_DATA data,
 651                               TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
 652                               int *cstatus)
 653 {
 654         struct ctdb_req_control req;
 655         struct ctdb_reply_control *reply = NULL;
 656         struct ctdbd_connection *new_conn = NULL;
 657         NTSTATUS status;
 658
 659         if (conn == NULL) {
 660                 status = ctdbd_init_connection(NULL, &new_conn);
 661
 662                 if (!NT_STATUS_IS_OK(status)) {
 663                         DEBUG(10, ("Could not init temp connection: %s\n",
 664                                    nt_errstr(status)));
 665                         goto fail;
 666                 }
 667
 668                 conn = new_conn;
 669         }
 670
 671         ZERO_STRUCT(req);
 672         req.hdr.length = offsetof(struct ctdb_req_control, data) + data.dsize;
 673         req.hdr.ctdb_magic   = CTDB_MAGIC;
 674         req.hdr.ctdb_version = CTDB_VERSION;
 675         req.hdr.operation    = CTDB_REQ_CONTROL;
 676         req.hdr.reqid        = ++conn->reqid;
 677         req.hdr.destnode     = vnn;
 678         req.opcode           = opcode;
 679         req.srvid            = srvid;
 680         req.datalen          = data.dsize;
 681
 682         status = packet_send(
 683                 conn->pkt, 2,
 684                 data_blob_const(&req, offsetof(struct ctdb_req_control, data)),
 685                 data);
 686
 687         if (!NT_STATUS_IS_OK(status)) {
 688                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 689                 goto fail;
 690         }
 691
 692         status = packet_flush(conn->pkt);
 693
 694         if (!NT_STATUS_IS_OK(status)) {
 695                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 696                 cluster_fatal("cluster dispatch daemon control write error\n");
 697         }
 698
 699         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 700
 701         if (!NT_STATUS_IS_OK(status)) {
 702                 DEBUG(10, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 703                 goto fail;
 704         }
 705
 706         if (reply->hdr.operation != CTDB_REPLY_CONTROL) {
 707                 DEBUG(0, ("received invalid reply\n"));
 708                 goto fail;
 709         }
 710
 711         if (outdata) {
 712                 if (!(outdata->dptr = (uint8 *)talloc_memdup(
 713                               mem_ctx, reply->data, reply->datalen))) {
 714                         TALLOC_FREE(reply);
 715                         return NT_STATUS_NO_MEMORY;
 716                 }
 717                 outdata->dsize = reply->datalen;
 718         }
 719         if (cstatus) {
 720                 (*cstatus) = reply->status;
 721         }
 722
 723         status = NT_STATUS_OK;
 724
 725  fail:
 726         TALLOC_FREE(new_conn);
 727         TALLOC_FREE(reply);
 728         return status;
 729 }
 730
 731 /*
 732  * see if a remote process exists
 733  */
 734 BOOL ctdbd_process_exists(struct ctdbd_connection *conn, uint32 vnn, pid_t pid)
 735 {
 736         NTSTATUS status;
 737         TDB_DATA data;
 738         int32_t cstatus;
 739
 740         data.dptr = (uint8_t*)&pid;
 741         data.dsize = sizeof(pid);
 742
 743         status = ctdbd_control(conn, vnn, CTDB_CONTROL_PROCESS_EXISTS, 0,
 744                                data, NULL, NULL, &cstatus);
 745         if (!NT_STATUS_IS_OK(status)) {
 746                 DEBUG(0, (__location__ " ctdb_control for process_exists "
 747                           "failed\n"));
 748                 return False;
 749         }
 750
 751         return cstatus == 0;
 752 }
 753
 754 /*
 755  * Get a db path
 756  */
 757 char *ctdbd_dbpath(struct ctdbd_connection *conn,
 758                    TALLOC_CTX *mem_ctx, uint32_t db_id)
 759 {
 760         NTSTATUS status;
 761         TDB_DATA data;
 762         int32_t cstatus;
 763
 764         data.dptr = (uint8_t*)&db_id;
 765         data.dsize = sizeof(db_id);
 766
 767         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 768                                CTDB_CONTROL_GETDBPATH, 0, data,
 769                                mem_ctx, &data, &cstatus);
 770         if (!NT_STATUS_IS_OK(status) || cstatus != 0) {
 771                 DEBUG(0,(__location__ " ctdb_control for getdbpath failed\n"));
 772                 return NULL;
 773         }
 774
 775         return (char *)data.dptr;
 776 }
 777
 778 /*
 779  * attach to a ctdb database
 780  */
 781 NTSTATUS ctdbd_db_attach(struct ctdbd_connection *conn,
 782                          const char *name, uint32_t *db_id, int tdb_flags)
 783 {
 784         NTSTATUS status;
 785         TDB_DATA data;
 786         int32_t cstatus;
 787
 788         data.dptr = (uint8_t*)name;
 789         data.dsize = strlen(name)+1;
 790
 791         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 792                                CTDB_CONTROL_DB_ATTACH, 0, data,
 793                                NULL, &data, &cstatus);
 794         if (!NT_STATUS_IS_OK(status)) {
 795                 DEBUG(0, (__location__ " ctdb_control for db_attach "
 796                           "failed: %s\n", nt_errstr(status)));
 797                 return status;
 798         }
 799
 800         if (cstatus != 0 || data.dsize != sizeof(uint32_t)) {
 801                 DEBUG(0,(__location__ " ctdb_control for db_attach failed\n"));
 802                 return NT_STATUS_INTERNAL_ERROR;
 803         }
 804
 805         *db_id = *(uint32_t *)data.dptr;
 806         talloc_free(data.dptr);
 807
 808         if (!(tdb_flags & TDB_SEQNUM)) {
 809                 return NT_STATUS_OK;
 810         }
 811
 812         data.dptr = (uint8_t *)db_id;
 813         data.dsize = sizeof(*db_id);
 814
 815         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 816                                CTDB_CONTROL_ENABLE_SEQNUM, 0, data,
 817                                NULL, NULL, &cstatus);
 818         if (!NT_STATUS_IS_OK(status) || cstatus != 0) {
 819                 DEBUG(0,(__location__ " ctdb_control for enable seqnum "
 820                          "failed\n"));
 821                 return NT_STATUS_IS_OK(status) ? NT_STATUS_INTERNAL_ERROR :
 822                         status;
 823         }
 824
 825         return NT_STATUS_OK;
 826 }
 827
 828 /*
 829  * force the migration of a record to this node
 830  */
 831 NTSTATUS ctdbd_migrate(struct ctdbd_connection *conn, uint32 db_id,
 832                        TDB_DATA key)
 833 {
 834         struct ctdb_req_call req;
 835         struct ctdb_reply_call *reply;
 836         NTSTATUS status;
 837
 838         ZERO_STRUCT(req);
 839
 840         req.hdr.length = offsetof(struct ctdb_req_call, data) + key.dsize;
 841         req.hdr.ctdb_magic   = CTDB_MAGIC;
 842         req.hdr.ctdb_version = CTDB_VERSION;
 843         req.hdr.operation    = CTDB_REQ_CALL;
 844         req.hdr.reqid        = ++conn->reqid;
 845         req.flags            = CTDB_IMMEDIATE_MIGRATION;
 846         req.callid           = CTDB_NULL_FUNC;
 847         req.db_id            = db_id;
 848         req.keylen           = key.dsize;
 849
 850         status = packet_send(
 851                 conn->pkt, 2,
 852                 data_blob_const(&req, offsetof(struct ctdb_req_call, data)),
 853                 key);
 854
 855         if (!NT_STATUS_IS_OK(status)) {
 856                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 857                 return status;
 858         }
 859
 860         status = packet_flush(conn->pkt);
 861
 862         if (!NT_STATUS_IS_OK(status)) {
 863                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 864                 cluster_fatal("cluster dispatch daemon control write error\n");
 865         }
 866
 867         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 868
 869         if (!NT_STATUS_IS_OK(status)) {
 870                 DEBUG(0, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 871                 goto fail;
 872         }
 873
 874         if (reply->hdr.operation != CTDB_REPLY_CALL) {
 875                 DEBUG(0, ("received invalid reply\n"));
 876                 status = NT_STATUS_INTERNAL_ERROR;
 877                 goto fail;
 878         }
 879
 880         status = NT_STATUS_OK;
 881  fail:
 882
 883         TALLOC_FREE(reply);
 884         return status;
 885 }
 886
 887 /*
 888  * remotely fetch a record without locking it or forcing a migration
 889  */
 890 NTSTATUS ctdbd_fetch(struct ctdbd_connection *conn, uint32 db_id,
 891                      TDB_DATA key, TALLOC_CTX *mem_ctx, TDB_DATA *data)
 892 {
 893         struct ctdb_req_call req;
 894         struct ctdb_reply_call *reply;
 895         NTSTATUS status;
 896
 897         ZERO_STRUCT(req);
 898
 899         req.hdr.length = offsetof(struct ctdb_req_call, data) + key.dsize;
 900         req.hdr.ctdb_magic   = CTDB_MAGIC;
 901         req.hdr.ctdb_version = CTDB_VERSION;
 902         req.hdr.operation    = CTDB_REQ_CALL;
 903         req.hdr.reqid        = ++conn->reqid;
 904         req.flags            = 0;
 905         req.callid           = CTDB_FETCH_FUNC;
 906         req.db_id            = db_id;
 907         req.keylen           = key.dsize;
 908
 909         status = packet_send(
 910                 conn->pkt, 2,
 911                 data_blob_const(&req, offsetof(struct ctdb_req_call, data)),
 912                 key);
 913
 914         if (!NT_STATUS_IS_OK(status)) {
 915                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 916                 return status;
 917         }
 918
 919         status = packet_flush(conn->pkt);
 920
 921         if (!NT_STATUS_IS_OK(status)) {
 922                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 923                 cluster_fatal("cluster dispatch daemon control write error\n");
 924         }
 925
 926         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 927
 928         if (!NT_STATUS_IS_OK(status)) {
 929                 DEBUG(0, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 930                 goto fail;
 931         }
 932
 933         if (reply->hdr.operation != CTDB_REPLY_CALL) {
 934                 DEBUG(0, ("received invalid reply\n"));
 935                 status = NT_STATUS_INTERNAL_ERROR;
 936                 goto fail;
 937         }
 938
 939         data->dsize = reply->datalen;
 940         if (data->dsize == 0) {
 941                 data->dptr = NULL;
 942                 goto done;
 943         }
 944
 945         data->dptr = (uint8 *)talloc_memdup(mem_ctx, &reply->data[0],
 946                                             reply->datalen);
 947         if (data->dptr == NULL) {
 948                 DEBUG(0, ("talloc failed\n"));
 949                 status = NT_STATUS_NO_MEMORY;
 950                 goto fail;
 951         }
 952
 953  done:
 954         status = NT_STATUS_OK;
 955  fail:
 956         TALLOC_FREE(reply);
 957         return status;
 958 }
 959
 960 struct ctdbd_traverse_state {
 961         void (*fn)(TDB_DATA key, TDB_DATA data, void *private_data);
 962         void *private_data;
 963 };
 964
 965 /*
 966  * Handle a traverse record coming in on the ctdbd connection
 967  */
 968
 969 static NTSTATUS ctdb_traverse_handler(const struct data_blob *blob,
 970                                       void *private_data)
 971 {
 972         struct ctdbd_traverse_state *state =
 973                 (struct ctdbd_traverse_state *)private_data;
 974
 975         struct ctdb_req_message *m;
 976         struct ctdb_rec_data *d;
 977         TDB_DATA key, data;
 978
 979         m = (struct ctdb_req_message *)blob->data;
 980
 981         if (blob->length < sizeof(*m) || m->hdr.length != blob->length) {
 982                 DEBUG(0, ("Got invalid message of length %d\n",
 983                           (int)blob->length));
 984                 return NT_STATUS_UNEXPECTED_IO_ERROR;
 985         }
 986
 987         d = (struct ctdb_rec_data *)&m->data[0];
 988         if (m->datalen < sizeof(uint32_t) || m->datalen != d->length) {
 989                 DEBUG(0, ("Got invalid traverse data of length %d\n",
 990                           (int)m->datalen));
 991                 return NT_STATUS_UNEXPECTED_IO_ERROR;
 992         }
 993
 994         key.dsize = d->keylen;
 995         key.dptr  = &d->data[0];
 996         data.dsize = d->datalen;
 997         data.dptr = &d->data[d->keylen];
 998
 999         if (key.dsize == 0 && data.dsize == 0) {
1000                 /* end of traverse */
1001                 return NT_STATUS_END_OF_FILE;
1002         }
1003
1004         if (data.dsize < sizeof(struct ctdb_ltdb_header)) {
1005                 DEBUG(0, ("Got invalid ltdb header length %d\n",
1006                           (int)data.dsize));
1007                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1008         }
1009         data.dsize -= sizeof(struct ctdb_ltdb_header);
1010         data.dptr += sizeof(struct ctdb_ltdb_header);
1011
1012         if (state->fn) {
1013                 state->fn(key, data, state->private_data);
1014         }
1015
1016         return NT_STATUS_OK;
1017 }
1018
1019 /*
1020   Traverse a ctdb database. This uses a kind-of hackish way to open a second
1021   connection to ctdbd to avoid the hairy recursive and async problems with
1022   everything in-line.
1023 */
1024
1025 NTSTATUS ctdbd_traverse(uint32 db_id,
1026                         void (*fn)(TDB_DATA key, TDB_DATA data,
1027                                    void *private_data),
1028                         void *private_data)
1029 {
1030         struct ctdbd_connection *conn;
1031         NTSTATUS status;
1032
1033         TDB_DATA data;
1034         struct ctdb_traverse_start t;
1035         int cstatus;
1036         struct ctdbd_traverse_state state;
1037
1038         status = ctdbd_init_connection(NULL, &conn);
1039
1040         t.db_id = db_id;
1041         t.srvid = conn->rand_srvid;
1042         t.reqid = ++conn->reqid;
1043
1044         data.dptr = (uint8_t *)&t;
1045         data.dsize = sizeof(t);
1046
1047         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
1048                                CTDB_CONTROL_TRAVERSE_START, conn->rand_srvid,
1049                                data, NULL, NULL, &cstatus);
1050
1051         if (!NT_STATUS_IS_OK(status) || (cstatus != 0)) {
1052
1053                 DEBUG(0,("ctdbd_control failed: %s, %d\n", nt_errstr(status),
1054                          cstatus));
1055
1056                 if (NT_STATUS_IS_OK(status)) {
1057                         /*
1058                          * We need a mapping here
1059                          */
1060                         status = NT_STATUS_UNSUCCESSFUL;
1061                 }
1062                 goto done;
1063         }
1064
1065         state.fn = fn;
1066         state.private_data = private_data;
1067
1068         while (True) {
1069
1070                 status = NT_STATUS_OK;
1071
1072                 if (packet_handler(conn->pkt, ctdb_req_complete,
1073                                    ctdb_traverse_handler, &state, &status)) {
1074
1075                         if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
1076                                 status = NT_STATUS_OK;
1077                                 break;
1078                         }
1079
1080                         /*
1081                          * There might be more in the queue
1082                          */
1083                         continue;
1084                 }
1085
1086                 if (!NT_STATUS_IS_OK(status)) {
1087                         break;
1088                 }
1089
1090                 status = packet_fd_read_sync(conn->pkt);
1091
1092                 if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
1093                         status = NT_STATUS_OK;
1094                 }
1095
1096                 if (!NT_STATUS_IS_OK(status)) {
1097                         cluster_fatal("ctdbd died\n");
1098                 }
1099         }
1100
1101  done:
1102         TALLOC_FREE(conn);
1103         return status;
1104 }
1105
1106 /*
1107  * Register us as a server for a particular tcp connection
1108  */
1109
1110 NTSTATUS ctdbd_register_ips(struct ctdbd_connection *conn,
1111                             const struct sockaddr_in *server,
1112                             const struct sockaddr_in *client,
1113                             void (*release_ip_handler)(const char *ip_addr,
1114                                                        void *private_data),
1115                             void *private_data)
1116 {
1117         struct ctdb_control_tcp p;
1118         TDB_DATA data;
1119         NTSTATUS status;
1120
1121         /*
1122          * Only one connection so far
1123          */
1124         SMB_ASSERT(conn->release_ip_handler == NULL);
1125
1126         /*
1127          * We want to be told about IP releases
1128          */
1129
1130         status = register_with_ctdbd(conn, CTDB_SRVID_RELEASE_IP);
1131         if (!NT_STATUS_IS_OK(status)) {
1132                 return status;
1133         }
1134
1135         p.dest = *server;
1136         p.src = *client;
1137
1138         /*
1139          * inform ctdb of our tcp connection, so if IP takeover happens ctdb
1140          * can send an extra ack to trigger a reset for our client, so it
1141          * immediately reconnects
1142          */
1143         data.dptr = (uint8_t *)&p;
1144         data.dsize = sizeof(p);
1145
1146         return ctdbd_control(conn, CTDB_CURRENT_NODE,
1147                              CTDB_CONTROL_TCP_CLIENT,
1148                              CTDB_CTRL_FLAG_NOREPLY, data, NULL, NULL, NULL);
1149 }
1150
1151 /*
1152  * We want to handle reconfigure events
1153  */
1154 NTSTATUS ctdbd_register_reconfigure(struct ctdbd_connection *conn)
1155 {
1156         return register_with_ctdbd(conn, CTDB_SRVID_RECONFIGURE);
1157 }
1158
1159 #else
1160
1161 NTSTATUS ctdbd_init_connection(TALLOC_CTX *mem_ctx,
1162                                struct ctdbd_connection **pconn)
1163 {
1164         return NT_STATUS_NOT_IMPLEMENTED;
1165 }
1166
1167 #endif