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 3 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, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22
  23 #ifdef CLUSTER_SUPPORT
  24
  25 #include "librpc/gen_ndr/messaging.h"
  26 #include "librpc/gen_ndr/ndr_messaging.h"
  27
  28 /* paths to these include files come from --with-ctdb= in configure */
  29 #include "ctdb.h"
  30 #include "ctdb_private.h"
  31
  32 struct ctdbd_connection {
  33         struct messaging_context *msg_ctx;
  34         uint32 reqid;
  35         uint32 our_vnn;
  36         uint64 rand_srvid;
  37         struct packet_context *pkt;
  38         struct fd_event *fde;
  39
  40         void (*release_ip_handler)(const char *ip_addr, void *private_data);
  41         void *release_ip_priv;
  42 };
  43
  44 static NTSTATUS ctdbd_control(struct ctdbd_connection *conn,
  45                               uint32_t vnn, uint32 opcode,
  46                               uint64_t srvid, uint32_t flags, TDB_DATA data,
  47                               TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
  48                               int *cstatus);
  49
  50 /*
  51  * exit on fatal communications errors with the ctdbd daemon
  52  */
  53 static void cluster_fatal(const char *why)
  54 {
  55         DEBUG(0,("cluster fatal event: %s - exiting immediately\n", why));
  56         /* we don't use smb_panic() as we don't want to delay to write
  57            a core file. We need to release this process id immediately
  58            so that someone else can take over without getting sharing
  59            violations */
  60         _exit(0);
  61 }
  62
  63 /*
  64  *
  65  */
  66 static void ctdb_packet_dump(struct ctdb_req_header *hdr)
  67 {
  68         if (DEBUGLEVEL < 10) {
  69                 return;
  70         }
  71         DEBUGADD(10, ("len=%d, magic=%x, vers=%d, gen=%d, op=%d, reqid=%d\n",
  72                       (int)hdr->length, (int)hdr->ctdb_magic,
  73                       (int)hdr->ctdb_version, (int)hdr->generation,
  74                       (int)hdr->operation, (int)hdr->reqid));
  75 }
  76
  77 /*
  78  * Register a srvid with ctdbd
  79  */
  80 static NTSTATUS register_with_ctdbd(struct ctdbd_connection *conn,
  81                                     uint64_t srvid)
  82 {
  83
  84         int cstatus;
  85         return ctdbd_control(conn, CTDB_CURRENT_NODE,
  86                              CTDB_CONTROL_REGISTER_SRVID, srvid, 0,
  87                              tdb_null, NULL, NULL, &cstatus);
  88 }
  89
  90 /*
  91  * get our vnn from the cluster
  92  */
  93 static NTSTATUS get_cluster_vnn(struct ctdbd_connection *conn, uint32 *vnn)
  94 {
  95         int32_t cstatus=-1;
  96         NTSTATUS status;
  97         status = ctdbd_control(conn,
  98                                CTDB_CURRENT_NODE, CTDB_CONTROL_GET_PNN, 0, 0,
  99                                tdb_null, NULL, NULL, &cstatus);
 100         if (!NT_STATUS_IS_OK(status)) {
 101                 cluster_fatal("ctdbd_control failed\n");
 102         }
 103         *vnn = (uint32_t)cstatus;
 104         return status;
 105 }
 106
 107 uint32 ctdbd_vnn(const struct ctdbd_connection *conn)
 108 {
 109         return conn->our_vnn;
 110 }
 111
 112 /*
 113  * Get us a ctdb connection
 114  */
 115
 116 static NTSTATUS ctdbd_connect(TALLOC_CTX *mem_ctx,
 117                               struct packet_context **presult)
 118 {
 119         struct packet_context *result;
 120         const char *sockname = lp_ctdbd_socket();
 121         struct sockaddr_un addr;
 122         int fd;
 123
 124         if (!sockname || !*sockname) {
 125                 sockname = CTDB_PATH;
 126         }
 127
 128         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 129         if (fd == -1) {
 130                 DEBUG(3, ("Could not create socket: %s\n", strerror(errno)));
 131                 return map_nt_error_from_unix(errno);
 132         }
 133
 134         ZERO_STRUCT(addr);
 135         addr.sun_family = AF_UNIX;
 136         strncpy(addr.sun_path, sockname, sizeof(addr.sun_path));
 137
 138         if (sys_connect(fd, (struct sockaddr *)&addr) == -1) {
 139                 DEBUG(1, ("connect(%s) failed: %s\n", sockname,
 140                           strerror(errno)));
 141                 close(fd);
 142                 return map_nt_error_from_unix(errno);
 143         }
 144
 145         if (!(result = packet_init(mem_ctx, fd))) {
 146                 close(fd);
 147                 return NT_STATUS_NO_MEMORY;
 148         }
 149
 150         *presult = result;
 151         return NT_STATUS_OK;
 152 }
 153
 154 /*
 155  * Do we have a complete ctdb packet in the queue?
 156  */
 157
 158 static bool ctdb_req_complete(const struct data_blob *data,
 159                               size_t *length,
 160                               void *private_data)
 161 {
 162         uint32 msglen;
 163
 164         if (data->length < sizeof(msglen)) {
 165                 return False;
 166         }
 167
 168         msglen = *((uint32 *)data->data);
 169
 170         DEBUG(10, ("msglen = %d\n", msglen));
 171
 172         if (msglen < sizeof(struct ctdb_req_header)) {
 173                 DEBUG(0, ("Got invalid msglen: %d, expected at least %d for "
 174                           "the req_header\n", (int)msglen,
 175                           (int)sizeof(struct ctdb_req_header)));
 176                 cluster_fatal("ctdbd protocol error\n");
 177         }
 178
 179         if (data->length >= msglen) {
 180                 *length = msglen;
 181                 return True;
 182         }
 183
 184         return False;
 185 }
 186
 187 /*
 188  * State necessary to defer an incoming message while we are waiting for a
 189  * ctdb reply.
 190  */
 191
 192 struct deferred_msg_state {
 193         struct messaging_context *msg_ctx;
 194         struct messaging_rec *rec;
 195 };
 196
 197 /*
 198  * Timed event handler for the deferred message
 199  */
 200
 201 static void deferred_message_dispatch(struct event_context *event_ctx,
 202                                       struct timed_event *te,
 203                                       const struct timeval *now,
 204                                       void *private_data)
 205 {
 206         struct deferred_msg_state *state = talloc_get_type_abort(
 207                 private_data, struct deferred_msg_state);
 208
 209         messaging_dispatch_rec(state->msg_ctx, state->rec);
 210         TALLOC_FREE(state);
 211         TALLOC_FREE(te);
 212 }
 213
 214 struct req_pull_state {
 215         TALLOC_CTX *mem_ctx;
 216         DATA_BLOB req;
 217 };
 218
 219 /*
 220  * Pull a ctdb request out of the incoming packet queue
 221  */
 222
 223 static NTSTATUS ctdb_req_pull(const struct data_blob *data,
 224                               void *private_data)
 225 {
 226         struct req_pull_state *state = (struct req_pull_state *)private_data;
 227
 228         state->req = data_blob_talloc(state->mem_ctx, data->data,
 229                                       data->length);
 230         if (state->req.data == NULL) {
 231                 return NT_STATUS_NO_MEMORY;
 232         }
 233         return NT_STATUS_OK;
 234 }
 235
 236 /*
 237  * Fetch a messaging_rec from an incoming ctdb style message
 238  */
 239
 240 static struct messaging_rec *ctdb_pull_messaging_rec(TALLOC_CTX *mem_ctx,
 241                                                      size_t overall_length,
 242                                                      struct ctdb_req_message *msg)
 243 {
 244         struct messaging_rec *result;
 245         DATA_BLOB blob;
 246         enum ndr_err_code ndr_err;
 247
 248         if ((overall_length < offsetof(struct ctdb_req_message, data))
 249             || (overall_length
 250                 < offsetof(struct ctdb_req_message, data) + msg->datalen)) {
 251
 252                 cluster_fatal("got invalid msg length");
 253         }
 254
 255         if (!(result = TALLOC_P(mem_ctx, struct messaging_rec))) {
 256                 DEBUG(0, ("talloc failed\n"));
 257                 return NULL;
 258         }
 259
 260         blob = data_blob_const(msg->data, msg->datalen);
 261
 262         ndr_err = ndr_pull_struct_blob(
 263                 &blob, result, result,
 264                 (ndr_pull_flags_fn_t)ndr_pull_messaging_rec);
 265
 266         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 267                 DEBUG(0, ("ndr_pull_struct_blob failed: %s\n",
 268                           ndr_errstr(ndr_err)));
 269                 TALLOC_FREE(result);
 270                 return NULL;
 271         }
 272
 273         if (DEBUGLEVEL >= 10) {
 274                 DEBUG(10, ("ctdb_pull_messaging_rec:\n"));
 275                 NDR_PRINT_DEBUG(messaging_rec, result);
 276         }
 277
 278         return result;
 279 }
 280
 281 /*
 282  * Read a full ctdbd request. If we have a messaging context, defer incoming
 283  * messages that might come in between.
 284  */
 285
 286 static NTSTATUS ctdb_read_req(struct ctdbd_connection *conn, uint32 reqid,
 287                               TALLOC_CTX *mem_ctx, void *result)
 288 {
 289         struct ctdb_req_header *hdr;
 290         struct req_pull_state state;
 291         NTSTATUS status;
 292
 293  again:
 294
 295         status = packet_fd_read_sync(conn->pkt);
 296
 297         if (NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_BUSY)) {
 298                 /* EAGAIN */
 299                 goto again;
 300         } else if (NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
 301                 /* EAGAIN */
 302                 goto again;
 303         }
 304
 305         if (!NT_STATUS_IS_OK(status)) {
 306                 DEBUG(0, ("packet_fd_read failed: %s\n", nt_errstr(status)));
 307                 cluster_fatal("ctdbd died\n");
 308         }
 309
 310  next_pkt:
 311
 312         ZERO_STRUCT(state);
 313         state.mem_ctx = mem_ctx;
 314
 315         if (!packet_handler(conn->pkt, ctdb_req_complete, ctdb_req_pull,
 316                             &state, &status)) {
 317                 /*
 318                  * Not enough data
 319                  */
 320                 DEBUG(10, ("not enough data from ctdb socket, retrying\n"));
 321                 goto again;
 322         }
 323
 324         if (!NT_STATUS_IS_OK(status)) {
 325                 DEBUG(0, ("Could not read packet: %s\n", nt_errstr(status)));
 326                 cluster_fatal("ctdbd died\n");
 327         }
 328
 329         hdr = (struct ctdb_req_header *)state.req.data;
 330
 331         DEBUG(10, ("Received ctdb packet\n"));
 332         ctdb_packet_dump(hdr);
 333
 334         if (hdr->operation == CTDB_REQ_MESSAGE) {
 335                 struct timed_event *evt;
 336                 struct deferred_msg_state *msg_state;
 337                 struct ctdb_req_message *msg = (struct ctdb_req_message *)hdr;
 338
 339                 if (conn->msg_ctx == NULL) {
 340                         DEBUG(1, ("Got a message without having a msg ctx, "
 341                                   "dropping msg %llu\n",
 342                                   (long long unsigned)msg->srvid));
 343                         goto next_pkt;
 344                 }
 345
 346                 if ((conn->release_ip_handler != NULL)
 347                     && (msg->srvid == CTDB_SRVID_RELEASE_IP)) {
 348                         /* must be dispatched immediately */
 349                         DEBUG(10, ("received CTDB_SRVID_RELEASE_IP\n"));
 350                         conn->release_ip_handler((const char *)msg->data,
 351                                                  conn->release_ip_priv);
 352                         TALLOC_FREE(hdr);
 353                         goto next_pkt;
 354                 }
 355
 356                 if (msg->srvid == CTDB_SRVID_RECONFIGURE) {
 357                         DEBUG(0,("Got cluster reconfigure message in ctdb_read_req\n"));
 358                         messaging_send(conn->msg_ctx, procid_self(),
 359                                        MSG_SMB_BRL_VALIDATE, &data_blob_null);
 360                         TALLOC_FREE(hdr);
 361                         goto next_pkt;
 362                 }
 363
 364                 if (!(msg_state = TALLOC_P(NULL, struct deferred_msg_state))) {
 365                         DEBUG(0, ("talloc failed\n"));
 366                         TALLOC_FREE(hdr);
 367                         goto next_pkt;
 368                 }
 369
 370                 if (!(msg_state->rec = ctdb_pull_messaging_rec(
 371                               msg_state, state.req.length, msg))) {
 372                         DEBUG(0, ("ctdbd_pull_messaging_rec failed\n"));
 373                         TALLOC_FREE(msg_state);
 374                         TALLOC_FREE(hdr);
 375                         goto next_pkt;
 376                 }
 377
 378                 TALLOC_FREE(hdr);
 379
 380                 msg_state->msg_ctx = conn->msg_ctx;
 381
 382                 /*
 383                  * We're waiting for a call reply, but an async message has
 384                  * crossed. Defer dispatching to the toplevel event loop.
 385                  */
 386                 evt = event_add_timed(conn->msg_ctx->event_ctx,
 387                                       conn->msg_ctx->event_ctx,
 388                                       timeval_zero(),
 389                                       "deferred_message_dispatch",
 390                                       deferred_message_dispatch,
 391                                       msg_state);
 392                 if (evt == NULL) {
 393                         DEBUG(0, ("event_add_timed failed\n"));
 394                         TALLOC_FREE(msg_state);
 395                         TALLOC_FREE(hdr);
 396                         goto next_pkt;
 397                 }
 398
 399                 goto next_pkt;
 400         }
 401
 402         if (hdr->reqid != reqid) {
 403                 /* we got the wrong reply */
 404                 DEBUG(0,("Discarding mismatched ctdb reqid %u should have "
 405                          "been %u\n", hdr->reqid, reqid));
 406                 TALLOC_FREE(hdr);
 407                 goto again;
 408         }
 409
 410         *((void **)result) = talloc_move(mem_ctx, &hdr);
 411
 412         return NT_STATUS_OK;
 413 }
 414
 415 /*
 416  * Get us a ctdbd connection
 417  */
 418
 419 NTSTATUS ctdbd_init_connection(TALLOC_CTX *mem_ctx,
 420                                struct ctdbd_connection **pconn)
 421 {
 422         struct ctdbd_connection *conn;
 423         NTSTATUS status;
 424
 425         if (!(conn = TALLOC_ZERO_P(mem_ctx, struct ctdbd_connection))) {
 426                 DEBUG(0, ("talloc failed\n"));
 427                 return NT_STATUS_NO_MEMORY;
 428         }
 429
 430         status = ctdbd_connect(conn, &conn->pkt);
 431
 432         if (!NT_STATUS_IS_OK(status)) {
 433                 DEBUG(10, ("ctdbd_connect failed: %s\n", nt_errstr(status)));
 434                 goto fail;
 435         }
 436
 437         status = get_cluster_vnn(conn, &conn->our_vnn);
 438
 439         if (!NT_STATUS_IS_OK(status)) {
 440                 DEBUG(10, ("get_cluster_vnn failed: %s\n", nt_errstr(status)));
 441                 goto fail;
 442         }
 443
 444         generate_random_buffer((unsigned char *)&conn->rand_srvid,
 445                                sizeof(conn->rand_srvid));
 446
 447         status = register_with_ctdbd(conn, conn->rand_srvid);
 448
 449         if (!NT_STATUS_IS_OK(status)) {
 450                 DEBUG(5, ("Could not register random srvid: %s\n",
 451                           nt_errstr(status)));
 452                 goto fail;
 453         }
 454
 455         *pconn = conn;
 456         return NT_STATUS_OK;
 457
 458  fail:
 459         TALLOC_FREE(conn);
 460         return status;
 461 }
 462
 463 /*
 464  * Get us a ctdbd connection and register us as a process
 465  */
 466
 467 NTSTATUS ctdbd_messaging_connection(TALLOC_CTX *mem_ctx,
 468                                     struct ctdbd_connection **pconn)
 469 {
 470         struct ctdbd_connection *conn;
 471         NTSTATUS status;
 472
 473         status = ctdbd_init_connection(mem_ctx, &conn);
 474
 475         if (!NT_STATUS_IS_OK(status)) {
 476                 return status;
 477         }
 478
 479         status = register_with_ctdbd(conn, (uint64_t)sys_getpid());
 480         if (!NT_STATUS_IS_OK(status)) {
 481                 goto fail;
 482         }
 483
 484         status = register_with_ctdbd(conn, MSG_SRVID_SAMBA);
 485         if (!NT_STATUS_IS_OK(status)) {
 486                 goto fail;
 487         }
 488
 489         *pconn = conn;
 490         return NT_STATUS_OK;
 491
 492  fail:
 493         TALLOC_FREE(conn);
 494         return status;
 495 }
 496
 497 /*
 498  * Packet handler to receive and handle a ctdb message
 499  */
 500 static NTSTATUS ctdb_handle_message(const struct data_blob *data,
 501                                     void *private_data)
 502 {
 503         struct ctdbd_connection *conn = talloc_get_type_abort(
 504                 private_data, struct ctdbd_connection);
 505         struct ctdb_req_message *msg;
 506         struct messaging_rec *msg_rec;
 507
 508         msg = (struct ctdb_req_message *)data->data;
 509
 510         if (msg->hdr.operation != CTDB_REQ_MESSAGE) {
 511                 DEBUG(0, ("Received async msg of type %u, discarding\n",
 512                           msg->hdr.operation));
 513                 return NT_STATUS_INVALID_PARAMETER;
 514         }
 515
 516         if ((conn->release_ip_handler != NULL)
 517             && (msg->srvid == CTDB_SRVID_RELEASE_IP)) {
 518                 /* must be dispatched immediately */
 519                 DEBUG(10, ("received CTDB_SRVID_RELEASE_IP\n"));
 520                 conn->release_ip_handler((const char *)msg->data,
 521                                          conn->release_ip_priv);
 522                 return NT_STATUS_OK;
 523         }
 524
 525         SMB_ASSERT(conn->msg_ctx != NULL);
 526
 527         if (msg->srvid == CTDB_SRVID_RECONFIGURE) {
 528                 DEBUG(0,("Got cluster reconfigure message\n"));
 529                 /*
 530                  * when the cluster is reconfigured, we need to clean the brl
 531                  * database
 532                  */
 533                 messaging_send(conn->msg_ctx, procid_self(),
 534                                MSG_SMB_BRL_VALIDATE, &data_blob_null);
 535
 536                 /*
 537                  * it's possible that we have just rejoined the cluster after
 538                  * an outage. In that case our pending locks could have been
 539                  * removed from the lockdb, so retry them once more
 540                  */
 541                 message_send_all(conn->msg_ctx, MSG_SMB_UNLOCK, NULL, 0, NULL);
 542
 543                 return NT_STATUS_OK;
 544
 545         }
 546
 547         /* only messages to our pid or the broadcast are valid here */
 548         if (msg->srvid != sys_getpid() && msg->srvid != MSG_SRVID_SAMBA) {
 549                 DEBUG(0,("Got unexpected message with srvid=%llu\n",
 550                          (unsigned long long)msg->srvid));
 551                 return NT_STATUS_OK;
 552         }
 553
 554         if (!(msg_rec = ctdb_pull_messaging_rec(NULL, data->length, msg))) {
 555                 DEBUG(10, ("ctdb_pull_messaging_rec failed\n"));
 556                 return NT_STATUS_NO_MEMORY;
 557         }
 558
 559         messaging_dispatch_rec(conn->msg_ctx, msg_rec);
 560
 561         TALLOC_FREE(msg_rec);
 562         return NT_STATUS_OK;
 563 }
 564
 565 /*
 566  * The ctdbd socket is readable asynchronuously
 567  */
 568
 569 static void ctdbd_socket_handler(struct event_context *event_ctx,
 570                                  struct fd_event *event,
 571                                  uint16 flags,
 572                                  void *private_data)
 573 {
 574         struct ctdbd_connection *conn = talloc_get_type_abort(
 575                 private_data, struct ctdbd_connection);
 576
 577         NTSTATUS status;
 578
 579         status = packet_fd_read(conn->pkt);
 580
 581         if (!NT_STATUS_IS_OK(status)) {
 582                 DEBUG(0, ("packet_fd_read failed: %s\n", nt_errstr(status)));
 583                 cluster_fatal("ctdbd died\n");
 584         }
 585
 586         while (packet_handler(conn->pkt, ctdb_req_complete,
 587                               ctdb_handle_message, conn, &status)) {
 588                 if (!NT_STATUS_IS_OK(status)) {
 589                         DEBUG(10, ("could not handle incoming message: %s\n",
 590                                    nt_errstr(status)));
 591                 }
 592         }
 593 }
 594
 595 /*
 596  * Prepare a ctdbd connection to receive messages
 597  */
 598
 599 NTSTATUS ctdbd_register_msg_ctx(struct ctdbd_connection *conn,
 600                                 struct messaging_context *msg_ctx)
 601 {
 602         SMB_ASSERT(conn->msg_ctx == NULL);
 603         SMB_ASSERT(conn->fde == NULL);
 604
 605         if (!(conn->fde = event_add_fd(msg_ctx->event_ctx, conn,
 606                                        packet_get_fd(conn->pkt),
 607                                        EVENT_FD_READ,
 608                                        ctdbd_socket_handler,
 609                                        conn))) {
 610                 DEBUG(0, ("event_add_fd failed\n"));
 611                 return NT_STATUS_NO_MEMORY;
 612         }
 613
 614         conn->msg_ctx = msg_ctx;
 615
 616         return NT_STATUS_OK;
 617 }
 618
 619 /*
 620  * Send a messaging message across a ctdbd
 621  */
 622
 623 NTSTATUS ctdbd_messaging_send(struct ctdbd_connection *conn,
 624                               uint32 dst_vnn, uint64 dst_srvid,
 625                               struct messaging_rec *msg)
 626 {
 627         struct ctdb_req_message r;
 628         TALLOC_CTX *mem_ctx;
 629         DATA_BLOB blob;
 630         NTSTATUS status;
 631         enum ndr_err_code ndr_err;
 632
 633         if (!(mem_ctx = talloc_init("ctdbd_messaging_send"))) {
 634                 DEBUG(0, ("talloc failed\n"));
 635                 return NT_STATUS_NO_MEMORY;
 636         }
 637
 638         ndr_err = ndr_push_struct_blob(
 639                 &blob, mem_ctx, msg,
 640                 (ndr_push_flags_fn_t)ndr_push_messaging_rec);
 641
 642         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 643                 DEBUG(0, ("ndr_push_struct_blob failed: %s\n",
 644                           ndr_errstr(ndr_err)));
 645                 status = ndr_map_error2ntstatus(ndr_err);
 646                 goto fail;
 647         }
 648
 649         r.hdr.length = offsetof(struct ctdb_req_message, data) + blob.length;
 650         r.hdr.ctdb_magic = CTDB_MAGIC;
 651         r.hdr.ctdb_version = CTDB_VERSION;
 652         r.hdr.generation = 1;
 653         r.hdr.operation  = CTDB_REQ_MESSAGE;
 654         r.hdr.destnode   = dst_vnn;
 655         r.hdr.srcnode    = conn->our_vnn;
 656         r.hdr.reqid      = 0;
 657         r.srvid          = dst_srvid;
 658         r.datalen        = blob.length;
 659
 660         DEBUG(10, ("ctdbd_messaging_send: Sending ctdb packet\n"));
 661         ctdb_packet_dump(&r.hdr);
 662
 663         status = packet_send(
 664                 conn->pkt, 2,
 665                 data_blob_const(&r, offsetof(struct ctdb_req_message, data)),
 666                 blob);
 667
 668         if (!NT_STATUS_IS_OK(status)) {
 669                 DEBUG(0, ("packet_send failed: %s\n", nt_errstr(status)));
 670                 goto fail;
 671         }
 672
 673         status = packet_flush(conn->pkt);
 674
 675         if (!NT_STATUS_IS_OK(status)) {
 676                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 677                 cluster_fatal("cluster dispatch daemon msg write error\n");
 678         }
 679
 680         status = NT_STATUS_OK;
 681  fail:
 682         TALLOC_FREE(mem_ctx);
 683         return status;
 684 }
 685
 686 /*
 687  * send/recv a generic ctdb control message
 688  */
 689 static NTSTATUS ctdbd_control(struct ctdbd_connection *conn,
 690                               uint32_t vnn, uint32 opcode,
 691                               uint64_t srvid, uint32_t flags,
 692                               TDB_DATA data,
 693                               TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
 694                               int *cstatus)
 695 {
 696         struct ctdb_req_control req;
 697         struct ctdb_reply_control *reply = NULL;
 698         struct ctdbd_connection *new_conn = NULL;
 699         NTSTATUS status;
 700
 701         /* the samba3 ctdb code can't handle NOREPLY yet */
 702         flags &= ~CTDB_CTRL_FLAG_NOREPLY;
 703
 704         if (conn == NULL) {
 705                 status = ctdbd_init_connection(NULL, &new_conn);
 706
 707                 if (!NT_STATUS_IS_OK(status)) {
 708                         DEBUG(10, ("Could not init temp connection: %s\n",
 709                                    nt_errstr(status)));
 710                         goto fail;
 711                 }
 712
 713                 conn = new_conn;
 714         }
 715
 716         ZERO_STRUCT(req);
 717         req.hdr.length = offsetof(struct ctdb_req_control, data) + data.dsize;
 718         req.hdr.ctdb_magic   = CTDB_MAGIC;
 719         req.hdr.ctdb_version = CTDB_VERSION;
 720         req.hdr.operation    = CTDB_REQ_CONTROL;
 721         req.hdr.reqid        = ++conn->reqid;
 722         req.hdr.destnode     = vnn;
 723         req.opcode           = opcode;
 724         req.srvid            = srvid;
 725         req.datalen          = data.dsize;
 726
 727         DEBUG(10, ("ctdbd_control: Sending ctdb packet\n"));
 728         ctdb_packet_dump(&req.hdr);
 729
 730         status = packet_send(
 731                 conn->pkt, 2,
 732                 data_blob_const(&req, offsetof(struct ctdb_req_control, data)),
 733                 data_blob_const(data.dptr, data.dsize));
 734
 735         if (!NT_STATUS_IS_OK(status)) {
 736                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 737                 goto fail;
 738         }
 739
 740         status = packet_flush(conn->pkt);
 741
 742         if (!NT_STATUS_IS_OK(status)) {
 743                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 744                 cluster_fatal("cluster dispatch daemon control write error\n");
 745         }
 746
 747         if (flags & CTDB_CTRL_FLAG_NOREPLY) {
 748                 TALLOC_FREE(new_conn);
 749                 return NT_STATUS_OK;
 750         }
 751
 752         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 753
 754         if (!NT_STATUS_IS_OK(status)) {
 755                 DEBUG(10, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 756                 goto fail;
 757         }
 758
 759         if (reply->hdr.operation != CTDB_REPLY_CONTROL) {
 760                 DEBUG(0, ("received invalid reply\n"));
 761                 goto fail;
 762         }
 763
 764         if (outdata) {
 765                 if (!(outdata->dptr = (uint8 *)talloc_memdup(
 766                               mem_ctx, reply->data, reply->datalen))) {
 767                         TALLOC_FREE(reply);
 768                         return NT_STATUS_NO_MEMORY;
 769                 }
 770                 outdata->dsize = reply->datalen;
 771         }
 772         if (cstatus) {
 773                 (*cstatus) = reply->status;
 774         }
 775
 776         status = NT_STATUS_OK;
 777
 778  fail:
 779         TALLOC_FREE(new_conn);
 780         TALLOC_FREE(reply);
 781         return status;
 782 }
 783
 784 /*
 785  * see if a remote process exists
 786  */
 787 bool ctdbd_process_exists(struct ctdbd_connection *conn, uint32 vnn, pid_t pid)
 788 {
 789         NTSTATUS status;
 790         TDB_DATA data;
 791         int32_t cstatus;
 792
 793         data.dptr = (uint8_t*)&pid;
 794         data.dsize = sizeof(pid);
 795
 796         status = ctdbd_control(conn, vnn, CTDB_CONTROL_PROCESS_EXISTS, 0, 0,
 797                                data, NULL, NULL, &cstatus);
 798         if (!NT_STATUS_IS_OK(status)) {
 799                 DEBUG(0, (__location__ " ctdb_control for process_exists "
 800                           "failed\n"));
 801                 return False;
 802         }
 803
 804         return cstatus == 0;
 805 }
 806
 807 /*
 808  * Get a db path
 809  */
 810 char *ctdbd_dbpath(struct ctdbd_connection *conn,
 811                    TALLOC_CTX *mem_ctx, uint32_t db_id)
 812 {
 813         NTSTATUS status;
 814         TDB_DATA data;
 815         int32_t cstatus;
 816
 817         data.dptr = (uint8_t*)&db_id;
 818         data.dsize = sizeof(db_id);
 819
 820         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 821                                CTDB_CONTROL_GETDBPATH, 0, 0, data,
 822                                mem_ctx, &data, &cstatus);
 823         if (!NT_STATUS_IS_OK(status) || cstatus != 0) {
 824                 DEBUG(0,(__location__ " ctdb_control for getdbpath failed\n"));
 825                 return NULL;
 826         }
 827
 828         return (char *)data.dptr;
 829 }
 830
 831 /*
 832  * attach to a ctdb database
 833  */
 834 NTSTATUS ctdbd_db_attach(struct ctdbd_connection *conn,
 835                          const char *name, uint32_t *db_id, int tdb_flags)
 836 {
 837         NTSTATUS status;
 838         TDB_DATA data;
 839         int32_t cstatus;
 840         bool persistent = (tdb_flags & TDB_CLEAR_IF_FIRST) == 0;
 841
 842         data.dptr = (uint8_t*)name;
 843         data.dsize = strlen(name)+1;
 844
 845         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 846                                persistent
 847                                ? CTDB_CONTROL_DB_ATTACH_PERSISTENT
 848                                : CTDB_CONTROL_DB_ATTACH,
 849                                0, 0, data, NULL, &data, &cstatus);
 850         if (!NT_STATUS_IS_OK(status)) {
 851                 DEBUG(0, (__location__ " ctdb_control for db_attach "
 852                           "failed: %s\n", nt_errstr(status)));
 853                 return status;
 854         }
 855
 856         if (cstatus != 0 || data.dsize != sizeof(uint32_t)) {
 857                 DEBUG(0,(__location__ " ctdb_control for db_attach failed\n"));
 858                 return NT_STATUS_INTERNAL_ERROR;
 859         }
 860
 861         *db_id = *(uint32_t *)data.dptr;
 862         talloc_free(data.dptr);
 863
 864         if (!(tdb_flags & TDB_SEQNUM)) {
 865                 return NT_STATUS_OK;
 866         }
 867
 868         data.dptr = (uint8_t *)db_id;
 869         data.dsize = sizeof(*db_id);
 870
 871         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 872                                CTDB_CONTROL_ENABLE_SEQNUM, 0, 0, data,
 873                                NULL, NULL, &cstatus);
 874         if (!NT_STATUS_IS_OK(status) || cstatus != 0) {
 875                 DEBUG(0,(__location__ " ctdb_control for enable seqnum "
 876                          "failed\n"));
 877                 return NT_STATUS_IS_OK(status) ? NT_STATUS_INTERNAL_ERROR :
 878                         status;
 879         }
 880
 881         return NT_STATUS_OK;
 882 }
 883
 884 /*
 885  * force the migration of a record to this node
 886  */
 887 NTSTATUS ctdbd_migrate(struct ctdbd_connection *conn, uint32 db_id,
 888                        TDB_DATA key)
 889 {
 890         struct ctdb_req_call req;
 891         struct ctdb_reply_call *reply;
 892         NTSTATUS status;
 893
 894         ZERO_STRUCT(req);
 895
 896         req.hdr.length = offsetof(struct ctdb_req_call, data) + key.dsize;
 897         req.hdr.ctdb_magic   = CTDB_MAGIC;
 898         req.hdr.ctdb_version = CTDB_VERSION;
 899         req.hdr.operation    = CTDB_REQ_CALL;
 900         req.hdr.reqid        = ++conn->reqid;
 901         req.flags            = CTDB_IMMEDIATE_MIGRATION;
 902         req.callid           = CTDB_NULL_FUNC;
 903         req.db_id            = db_id;
 904         req.keylen           = key.dsize;
 905
 906         DEBUG(10, ("ctdbd_migrate: Sending ctdb packet\n"));
 907         ctdb_packet_dump(&req.hdr);
 908
 909         status = packet_send(
 910                 conn->pkt, 2,
 911                 data_blob_const(&req, offsetof(struct ctdb_req_call, data)),
 912                 data_blob_const(key.dptr, key.dsize));
 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         status = NT_STATUS_OK;
 940  fail:
 941
 942         TALLOC_FREE(reply);
 943         return status;
 944 }
 945
 946 /*
 947  * remotely fetch a record without locking it or forcing a migration
 948  */
 949 NTSTATUS ctdbd_fetch(struct ctdbd_connection *conn, uint32 db_id,
 950                      TDB_DATA key, TALLOC_CTX *mem_ctx, TDB_DATA *data)
 951 {
 952         struct ctdb_req_call req;
 953         struct ctdb_reply_call *reply;
 954         NTSTATUS status;
 955
 956         ZERO_STRUCT(req);
 957
 958         req.hdr.length = offsetof(struct ctdb_req_call, data) + key.dsize;
 959         req.hdr.ctdb_magic   = CTDB_MAGIC;
 960         req.hdr.ctdb_version = CTDB_VERSION;
 961         req.hdr.operation    = CTDB_REQ_CALL;
 962         req.hdr.reqid        = ++conn->reqid;
 963         req.flags            = 0;
 964         req.callid           = CTDB_FETCH_FUNC;
 965         req.db_id            = db_id;
 966         req.keylen           = key.dsize;
 967
 968         status = packet_send(
 969                 conn->pkt, 2,
 970                 data_blob_const(&req, offsetof(struct ctdb_req_call, data)),
 971                 data_blob_const(key.dptr, key.dsize));
 972
 973         if (!NT_STATUS_IS_OK(status)) {
 974                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 975                 return status;
 976         }
 977
 978         status = packet_flush(conn->pkt);
 979
 980         if (!NT_STATUS_IS_OK(status)) {
 981                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 982                 cluster_fatal("cluster dispatch daemon control write error\n");
 983         }
 984
 985         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 986
 987         if (!NT_STATUS_IS_OK(status)) {
 988                 DEBUG(0, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 989                 goto fail;
 990         }
 991
 992         if (reply->hdr.operation != CTDB_REPLY_CALL) {
 993                 DEBUG(0, ("received invalid reply\n"));
 994                 status = NT_STATUS_INTERNAL_ERROR;
 995                 goto fail;
 996         }
 997
 998         data->dsize = reply->datalen;
 999         if (data->dsize == 0) {
1000                 data->dptr = NULL;
1001                 goto done;
1002         }
1003
1004         data->dptr = (uint8 *)talloc_memdup(mem_ctx, &reply->data[0],
1005                                             reply->datalen);
1006         if (data->dptr == NULL) {
1007                 DEBUG(0, ("talloc failed\n"));
1008                 status = NT_STATUS_NO_MEMORY;
1009                 goto fail;
1010         }
1011
1012  done:
1013         status = NT_STATUS_OK;
1014  fail:
1015         TALLOC_FREE(reply);
1016         return status;
1017 }
1018
1019 struct ctdbd_traverse_state {
1020         void (*fn)(TDB_DATA key, TDB_DATA data, void *private_data);
1021         void *private_data;
1022 };
1023
1024 /*
1025  * Handle a traverse record coming in on the ctdbd connection
1026  */
1027
1028 static NTSTATUS ctdb_traverse_handler(const struct data_blob *blob,
1029                                       void *private_data)
1030 {
1031         struct ctdbd_traverse_state *state =
1032                 (struct ctdbd_traverse_state *)private_data;
1033
1034         struct ctdb_req_message *m;
1035         struct ctdb_rec_data *d;
1036         TDB_DATA key, data;
1037
1038         m = (struct ctdb_req_message *)blob->data;
1039
1040         if (blob->length < sizeof(*m) || m->hdr.length != blob->length) {
1041                 DEBUG(0, ("Got invalid message of length %d\n",
1042                           (int)blob->length));
1043                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1044         }
1045
1046         d = (struct ctdb_rec_data *)&m->data[0];
1047         if (m->datalen < sizeof(uint32_t) || m->datalen != d->length) {
1048                 DEBUG(0, ("Got invalid traverse data of length %d\n",
1049                           (int)m->datalen));
1050                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1051         }
1052
1053         key.dsize = d->keylen;
1054         key.dptr  = &d->data[0];
1055         data.dsize = d->datalen;
1056         data.dptr = &d->data[d->keylen];
1057
1058         if (key.dsize == 0 && data.dsize == 0) {
1059                 /* end of traverse */
1060                 return NT_STATUS_END_OF_FILE;
1061         }
1062
1063         if (data.dsize < sizeof(struct ctdb_ltdb_header)) {
1064                 DEBUG(0, ("Got invalid ltdb header length %d\n",
1065                           (int)data.dsize));
1066                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1067         }
1068         data.dsize -= sizeof(struct ctdb_ltdb_header);
1069         data.dptr += sizeof(struct ctdb_ltdb_header);
1070
1071         if (state->fn) {
1072                 state->fn(key, data, state->private_data);
1073         }
1074
1075         return NT_STATUS_OK;
1076 }
1077
1078 /*
1079   Traverse a ctdb database. This uses a kind-of hackish way to open a second
1080   connection to ctdbd to avoid the hairy recursive and async problems with
1081   everything in-line.
1082 */
1083
1084 NTSTATUS ctdbd_traverse(uint32 db_id,
1085                         void (*fn)(TDB_DATA key, TDB_DATA data,
1086                                    void *private_data),
1087                         void *private_data)
1088 {
1089         struct ctdbd_connection *conn;
1090         NTSTATUS status;
1091
1092         TDB_DATA data;
1093         struct ctdb_traverse_start t;
1094         int cstatus;
1095         struct ctdbd_traverse_state state;
1096
1097         status = ctdbd_init_connection(NULL, &conn);
1098
1099         t.db_id = db_id;
1100         t.srvid = conn->rand_srvid;
1101         t.reqid = ++conn->reqid;
1102
1103         data.dptr = (uint8_t *)&t;
1104         data.dsize = sizeof(t);
1105
1106         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
1107                                CTDB_CONTROL_TRAVERSE_START, conn->rand_srvid, 0,
1108                                data, NULL, NULL, &cstatus);
1109
1110         if (!NT_STATUS_IS_OK(status) || (cstatus != 0)) {
1111
1112                 DEBUG(0,("ctdbd_control failed: %s, %d\n", nt_errstr(status),
1113                          cstatus));
1114
1115                 if (NT_STATUS_IS_OK(status)) {
1116                         /*
1117                          * We need a mapping here
1118                          */
1119                         status = NT_STATUS_UNSUCCESSFUL;
1120                 }
1121                 goto done;
1122         }
1123
1124         state.fn = fn;
1125         state.private_data = private_data;
1126
1127         while (True) {
1128
1129                 status = NT_STATUS_OK;
1130
1131                 if (packet_handler(conn->pkt, ctdb_req_complete,
1132                                    ctdb_traverse_handler, &state, &status)) {
1133
1134                         if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
1135                                 status = NT_STATUS_OK;
1136                                 break;
1137                         }
1138
1139                         /*
1140                          * There might be more in the queue
1141                          */
1142                         continue;
1143                 }
1144
1145                 if (!NT_STATUS_IS_OK(status)) {
1146                         break;
1147                 }
1148
1149                 status = packet_fd_read_sync(conn->pkt);
1150
1151                 if (NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
1152                         /*
1153                          * There might be more in the queue
1154                          */
1155                         continue;
1156                 }
1157
1158                 if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
1159                         status = NT_STATUS_OK;
1160                 }
1161
1162                 if (!NT_STATUS_IS_OK(status)) {
1163                         DEBUG(0, ("packet_fd_read_sync failed: %s\n", nt_errstr(status)));
1164                         cluster_fatal("ctdbd died\n");
1165                 }
1166         }
1167
1168  done:
1169         TALLOC_FREE(conn);
1170         return status;
1171 }
1172
1173 /*
1174  * Register us as a server for a particular tcp connection
1175  */
1176
1177 NTSTATUS ctdbd_register_ips(struct ctdbd_connection *conn,
1178                             const struct sockaddr_in *server,
1179                             const struct sockaddr_in *client,
1180                             void (*release_ip_handler)(const char *ip_addr,
1181                                                        void *private_data),
1182                             void *private_data)
1183 {
1184         struct ctdb_control_tcp p;
1185         TDB_DATA data;
1186         NTSTATUS status;
1187
1188         /*
1189          * Only one connection so far
1190          */
1191         SMB_ASSERT(conn->release_ip_handler == NULL);
1192
1193         conn->release_ip_handler = release_ip_handler;
1194
1195         /*
1196          * We want to be told about IP releases
1197          */
1198
1199         status = register_with_ctdbd(conn, CTDB_SRVID_RELEASE_IP);
1200         if (!NT_STATUS_IS_OK(status)) {
1201                 return status;
1202         }
1203
1204         p.dest = *server;
1205         p.src = *client;
1206
1207         /*
1208          * inform ctdb of our tcp connection, so if IP takeover happens ctdb
1209          * can send an extra ack to trigger a reset for our client, so it
1210          * immediately reconnects
1211          */
1212         data.dptr = (uint8_t *)&p;
1213         data.dsize = sizeof(p);
1214
1215         return ctdbd_control(conn, CTDB_CURRENT_NODE,
1216                              CTDB_CONTROL_TCP_CLIENT, 0,
1217                              CTDB_CTRL_FLAG_NOREPLY, data, NULL, NULL, NULL);
1218 }
1219
1220 /*
1221  * We want to handle reconfigure events
1222  */
1223 NTSTATUS ctdbd_register_reconfigure(struct ctdbd_connection *conn)
1224 {
1225         return register_with_ctdbd(conn, CTDB_SRVID_RECONFIGURE);
1226 }
1227
1228 /*
1229   call a control on the local node
1230  */
1231 NTSTATUS ctdbd_control_local(struct ctdbd_connection *conn, uint32 opcode,
1232                              uint64_t srvid, uint32_t flags, TDB_DATA data,
1233                              TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
1234                              int *cstatus)
1235 {
1236         return ctdbd_control(conn, CTDB_CURRENT_NODE, opcode, srvid, flags, data, mem_ctx, outdata, cstatus);
1237 }
1238
1239 #else
1240
1241 NTSTATUS ctdbd_init_connection(TALLOC_CTX *mem_ctx,
1242                                struct ctdbd_connection **pconn)
1243 {
1244         return NT_STATUS_NOT_IMPLEMENTED;
1245 }
1246
1247 #endif