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                                       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                                       msg_state);
 391                 if (evt == NULL) {
 392                         DEBUG(0, ("event_add_timed failed\n"));
 393                         TALLOC_FREE(msg_state);
 394                         TALLOC_FREE(hdr);
 395                         goto next_pkt;
 396                 }
 397
 398                 goto next_pkt;
 399         }
 400
 401         if (hdr->reqid != reqid) {
 402                 /* we got the wrong reply */
 403                 DEBUG(0,("Discarding mismatched ctdb reqid %u should have "
 404                          "been %u\n", hdr->reqid, reqid));
 405                 TALLOC_FREE(hdr);
 406                 goto again;
 407         }
 408
 409         *((void **)result) = talloc_move(mem_ctx, &hdr);
 410
 411         return NT_STATUS_OK;
 412 }
 413
 414 /*
 415  * Get us a ctdbd connection
 416  */
 417
 418 NTSTATUS ctdbd_init_connection(TALLOC_CTX *mem_ctx,
 419                                struct ctdbd_connection **pconn)
 420 {
 421         struct ctdbd_connection *conn;
 422         NTSTATUS status;
 423
 424         if (!(conn = TALLOC_ZERO_P(mem_ctx, struct ctdbd_connection))) {
 425                 DEBUG(0, ("talloc failed\n"));
 426                 return NT_STATUS_NO_MEMORY;
 427         }
 428
 429         status = ctdbd_connect(conn, &conn->pkt);
 430
 431         if (!NT_STATUS_IS_OK(status)) {
 432                 DEBUG(10, ("ctdbd_connect failed: %s\n", nt_errstr(status)));
 433                 goto fail;
 434         }
 435
 436         status = get_cluster_vnn(conn, &conn->our_vnn);
 437
 438         if (!NT_STATUS_IS_OK(status)) {
 439                 DEBUG(10, ("get_cluster_vnn failed: %s\n", nt_errstr(status)));
 440                 goto fail;
 441         }
 442
 443         generate_random_buffer((unsigned char *)&conn->rand_srvid,
 444                                sizeof(conn->rand_srvid));
 445
 446         status = register_with_ctdbd(conn, conn->rand_srvid);
 447
 448         if (!NT_STATUS_IS_OK(status)) {
 449                 DEBUG(5, ("Could not register random srvid: %s\n",
 450                           nt_errstr(status)));
 451                 goto fail;
 452         }
 453
 454         *pconn = conn;
 455         return NT_STATUS_OK;
 456
 457  fail:
 458         TALLOC_FREE(conn);
 459         return status;
 460 }
 461
 462 /*
 463  * Get us a ctdbd connection and register us as a process
 464  */
 465
 466 NTSTATUS ctdbd_messaging_connection(TALLOC_CTX *mem_ctx,
 467                                     struct ctdbd_connection **pconn)
 468 {
 469         struct ctdbd_connection *conn;
 470         NTSTATUS status;
 471
 472         status = ctdbd_init_connection(mem_ctx, &conn);
 473
 474         if (!NT_STATUS_IS_OK(status)) {
 475                 return status;
 476         }
 477
 478         status = register_with_ctdbd(conn, (uint64_t)sys_getpid());
 479         if (!NT_STATUS_IS_OK(status)) {
 480                 goto fail;
 481         }
 482
 483         status = register_with_ctdbd(conn, MSG_SRVID_SAMBA);
 484         if (!NT_STATUS_IS_OK(status)) {
 485                 goto fail;
 486         }
 487
 488         *pconn = conn;
 489         return NT_STATUS_OK;
 490
 491  fail:
 492         TALLOC_FREE(conn);
 493         return status;
 494 }
 495
 496 /*
 497  * Packet handler to receive and handle a ctdb message
 498  */
 499 static NTSTATUS ctdb_handle_message(const struct data_blob *data,
 500                                     void *private_data)
 501 {
 502         struct ctdbd_connection *conn = talloc_get_type_abort(
 503                 private_data, struct ctdbd_connection);
 504         struct ctdb_req_message *msg;
 505         struct messaging_rec *msg_rec;
 506
 507         msg = (struct ctdb_req_message *)data->data;
 508
 509         if (msg->hdr.operation != CTDB_REQ_MESSAGE) {
 510                 DEBUG(0, ("Received async msg of type %u, discarding\n",
 511                           msg->hdr.operation));
 512                 return NT_STATUS_INVALID_PARAMETER;
 513         }
 514
 515         if ((conn->release_ip_handler != NULL)
 516             && (msg->srvid == CTDB_SRVID_RELEASE_IP)) {
 517                 /* must be dispatched immediately */
 518                 DEBUG(10, ("received CTDB_SRVID_RELEASE_IP\n"));
 519                 conn->release_ip_handler((const char *)msg->data,
 520                                          conn->release_ip_priv);
 521                 return NT_STATUS_OK;
 522         }
 523
 524         SMB_ASSERT(conn->msg_ctx != NULL);
 525
 526         if (msg->srvid == CTDB_SRVID_RECONFIGURE) {
 527                 DEBUG(0,("Got cluster reconfigure message\n"));
 528                 /*
 529                  * when the cluster is reconfigured, we need to clean the brl
 530                  * database
 531                  */
 532                 messaging_send(conn->msg_ctx, procid_self(),
 533                                MSG_SMB_BRL_VALIDATE, &data_blob_null);
 534
 535                 /*
 536                  * it's possible that we have just rejoined the cluster after
 537                  * an outage. In that case our pending locks could have been
 538                  * removed from the lockdb, so retry them once more
 539                  */
 540                 message_send_all(conn->msg_ctx, MSG_SMB_UNLOCK, NULL, 0, NULL);
 541
 542                 return NT_STATUS_OK;
 543
 544         }
 545
 546         /* only messages to our pid or the broadcast are valid here */
 547         if (msg->srvid != sys_getpid() && msg->srvid != MSG_SRVID_SAMBA) {
 548                 DEBUG(0,("Got unexpected message with srvid=%llu\n",
 549                          (unsigned long long)msg->srvid));
 550                 return NT_STATUS_OK;
 551         }
 552
 553         if (!(msg_rec = ctdb_pull_messaging_rec(NULL, data->length, msg))) {
 554                 DEBUG(10, ("ctdb_pull_messaging_rec failed\n"));
 555                 return NT_STATUS_NO_MEMORY;
 556         }
 557
 558         messaging_dispatch_rec(conn->msg_ctx, msg_rec);
 559
 560         TALLOC_FREE(msg_rec);
 561         return NT_STATUS_OK;
 562 }
 563
 564 /*
 565  * The ctdbd socket is readable asynchronuously
 566  */
 567
 568 static void ctdbd_socket_handler(struct event_context *event_ctx,
 569                                  struct fd_event *event,
 570                                  uint16 flags,
 571                                  void *private_data)
 572 {
 573         struct ctdbd_connection *conn = talloc_get_type_abort(
 574                 private_data, struct ctdbd_connection);
 575
 576         NTSTATUS status;
 577
 578         status = packet_fd_read(conn->pkt);
 579
 580         if (!NT_STATUS_IS_OK(status)) {
 581                 DEBUG(0, ("packet_fd_read failed: %s\n", nt_errstr(status)));
 582                 cluster_fatal("ctdbd died\n");
 583         }
 584
 585         while (packet_handler(conn->pkt, ctdb_req_complete,
 586                               ctdb_handle_message, conn, &status)) {
 587                 if (!NT_STATUS_IS_OK(status)) {
 588                         DEBUG(10, ("could not handle incoming message: %s\n",
 589                                    nt_errstr(status)));
 590                 }
 591         }
 592 }
 593
 594 /*
 595  * Prepare a ctdbd connection to receive messages
 596  */
 597
 598 NTSTATUS ctdbd_register_msg_ctx(struct ctdbd_connection *conn,
 599                                 struct messaging_context *msg_ctx)
 600 {
 601         SMB_ASSERT(conn->msg_ctx == NULL);
 602         SMB_ASSERT(conn->fde == NULL);
 603
 604         if (!(conn->fde = event_add_fd(msg_ctx->event_ctx, conn,
 605                                        packet_get_fd(conn->pkt),
 606                                        EVENT_FD_READ,
 607                                        ctdbd_socket_handler,
 608                                        conn))) {
 609                 DEBUG(0, ("event_add_fd failed\n"));
 610                 return NT_STATUS_NO_MEMORY;
 611         }
 612
 613         conn->msg_ctx = msg_ctx;
 614
 615         return NT_STATUS_OK;
 616 }
 617
 618 /*
 619  * Send a messaging message across a ctdbd
 620  */
 621
 622 NTSTATUS ctdbd_messaging_send(struct ctdbd_connection *conn,
 623                               uint32 dst_vnn, uint64 dst_srvid,
 624                               struct messaging_rec *msg)
 625 {
 626         struct ctdb_req_message r;
 627         TALLOC_CTX *mem_ctx;
 628         DATA_BLOB blob;
 629         NTSTATUS status;
 630         enum ndr_err_code ndr_err;
 631
 632         if (!(mem_ctx = talloc_init("ctdbd_messaging_send"))) {
 633                 DEBUG(0, ("talloc failed\n"));
 634                 return NT_STATUS_NO_MEMORY;
 635         }
 636
 637         ndr_err = ndr_push_struct_blob(
 638                 &blob, mem_ctx, msg,
 639                 (ndr_push_flags_fn_t)ndr_push_messaging_rec);
 640
 641         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 642                 DEBUG(0, ("ndr_push_struct_blob failed: %s\n",
 643                           ndr_errstr(ndr_err)));
 644                 status = ndr_map_error2ntstatus(ndr_err);
 645                 goto fail;
 646         }
 647
 648         r.hdr.length = offsetof(struct ctdb_req_message, data) + blob.length;
 649         r.hdr.ctdb_magic = CTDB_MAGIC;
 650         r.hdr.ctdb_version = CTDB_VERSION;
 651         r.hdr.generation = 1;
 652         r.hdr.operation  = CTDB_REQ_MESSAGE;
 653         r.hdr.destnode   = dst_vnn;
 654         r.hdr.srcnode    = conn->our_vnn;
 655         r.hdr.reqid      = 0;
 656         r.srvid          = dst_srvid;
 657         r.datalen        = blob.length;
 658
 659         DEBUG(10, ("ctdbd_messaging_send: Sending ctdb packet\n"));
 660         ctdb_packet_dump(&r.hdr);
 661
 662         status = packet_send(
 663                 conn->pkt, 2,
 664                 data_blob_const(&r, offsetof(struct ctdb_req_message, data)),
 665                 blob);
 666
 667         if (!NT_STATUS_IS_OK(status)) {
 668                 DEBUG(0, ("packet_send failed: %s\n", nt_errstr(status)));
 669                 goto fail;
 670         }
 671
 672         status = packet_flush(conn->pkt);
 673
 674         if (!NT_STATUS_IS_OK(status)) {
 675                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 676                 cluster_fatal("cluster dispatch daemon msg write error\n");
 677         }
 678
 679         status = NT_STATUS_OK;
 680  fail:
 681         TALLOC_FREE(mem_ctx);
 682         return status;
 683 }
 684
 685 /*
 686  * send/recv a generic ctdb control message
 687  */
 688 static NTSTATUS ctdbd_control(struct ctdbd_connection *conn,
 689                               uint32_t vnn, uint32 opcode,
 690                               uint64_t srvid, uint32_t flags,
 691                               TDB_DATA data,
 692                               TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
 693                               int *cstatus)
 694 {
 695         struct ctdb_req_control req;
 696         struct ctdb_reply_control *reply = NULL;
 697         struct ctdbd_connection *new_conn = NULL;
 698         NTSTATUS status;
 699
 700         /* the samba3 ctdb code can't handle NOREPLY yet */
 701         flags &= ~CTDB_CTRL_FLAG_NOREPLY;
 702
 703         if (conn == NULL) {
 704                 status = ctdbd_init_connection(NULL, &new_conn);
 705
 706                 if (!NT_STATUS_IS_OK(status)) {
 707                         DEBUG(10, ("Could not init temp connection: %s\n",
 708                                    nt_errstr(status)));
 709                         goto fail;
 710                 }
 711
 712                 conn = new_conn;
 713         }
 714
 715         ZERO_STRUCT(req);
 716         req.hdr.length = offsetof(struct ctdb_req_control, data) + data.dsize;
 717         req.hdr.ctdb_magic   = CTDB_MAGIC;
 718         req.hdr.ctdb_version = CTDB_VERSION;
 719         req.hdr.operation    = CTDB_REQ_CONTROL;
 720         req.hdr.reqid        = ++conn->reqid;
 721         req.hdr.destnode     = vnn;
 722         req.opcode           = opcode;
 723         req.srvid            = srvid;
 724         req.datalen          = data.dsize;
 725
 726         DEBUG(10, ("ctdbd_control: Sending ctdb packet\n"));
 727         ctdb_packet_dump(&req.hdr);
 728
 729         status = packet_send(
 730                 conn->pkt, 2,
 731                 data_blob_const(&req, offsetof(struct ctdb_req_control, data)),
 732                 data_blob_const(data.dptr, data.dsize));
 733
 734         if (!NT_STATUS_IS_OK(status)) {
 735                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 736                 goto fail;
 737         }
 738
 739         status = packet_flush(conn->pkt);
 740
 741         if (!NT_STATUS_IS_OK(status)) {
 742                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 743                 cluster_fatal("cluster dispatch daemon control write error\n");
 744         }
 745
 746         if (flags & CTDB_CTRL_FLAG_NOREPLY) {
 747                 TALLOC_FREE(new_conn);
 748                 return NT_STATUS_OK;
 749         }
 750
 751         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 752
 753         if (!NT_STATUS_IS_OK(status)) {
 754                 DEBUG(10, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 755                 goto fail;
 756         }
 757
 758         if (reply->hdr.operation != CTDB_REPLY_CONTROL) {
 759                 DEBUG(0, ("received invalid reply\n"));
 760                 goto fail;
 761         }
 762
 763         if (outdata) {
 764                 if (!(outdata->dptr = (uint8 *)talloc_memdup(
 765                               mem_ctx, reply->data, reply->datalen))) {
 766                         TALLOC_FREE(reply);
 767                         return NT_STATUS_NO_MEMORY;
 768                 }
 769                 outdata->dsize = reply->datalen;
 770         }
 771         if (cstatus) {
 772                 (*cstatus) = reply->status;
 773         }
 774
 775         status = NT_STATUS_OK;
 776
 777  fail:
 778         TALLOC_FREE(new_conn);
 779         TALLOC_FREE(reply);
 780         return status;
 781 }
 782
 783 /*
 784  * see if a remote process exists
 785  */
 786 bool ctdbd_process_exists(struct ctdbd_connection *conn, uint32 vnn, pid_t pid)
 787 {
 788         NTSTATUS status;
 789         TDB_DATA data;
 790         int32_t cstatus;
 791
 792         data.dptr = (uint8_t*)&pid;
 793         data.dsize = sizeof(pid);
 794
 795         status = ctdbd_control(conn, vnn, CTDB_CONTROL_PROCESS_EXISTS, 0, 0,
 796                                data, NULL, NULL, &cstatus);
 797         if (!NT_STATUS_IS_OK(status)) {
 798                 DEBUG(0, (__location__ " ctdb_control for process_exists "
 799                           "failed\n"));
 800                 return False;
 801         }
 802
 803         return cstatus == 0;
 804 }
 805
 806 /*
 807  * Get a db path
 808  */
 809 char *ctdbd_dbpath(struct ctdbd_connection *conn,
 810                    TALLOC_CTX *mem_ctx, uint32_t db_id)
 811 {
 812         NTSTATUS status;
 813         TDB_DATA data;
 814         int32_t cstatus;
 815
 816         data.dptr = (uint8_t*)&db_id;
 817         data.dsize = sizeof(db_id);
 818
 819         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 820                                CTDB_CONTROL_GETDBPATH, 0, 0, data,
 821                                mem_ctx, &data, &cstatus);
 822         if (!NT_STATUS_IS_OK(status) || cstatus != 0) {
 823                 DEBUG(0,(__location__ " ctdb_control for getdbpath failed\n"));
 824                 return NULL;
 825         }
 826
 827         return (char *)data.dptr;
 828 }
 829
 830 /*
 831  * attach to a ctdb database
 832  */
 833 NTSTATUS ctdbd_db_attach(struct ctdbd_connection *conn,
 834                          const char *name, uint32_t *db_id, int tdb_flags)
 835 {
 836         NTSTATUS status;
 837         TDB_DATA data;
 838         int32_t cstatus;
 839         bool persistent = (tdb_flags & TDB_CLEAR_IF_FIRST) == 0;
 840
 841         data.dptr = (uint8_t*)name;
 842         data.dsize = strlen(name)+1;
 843
 844         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 845                                persistent
 846                                ? CTDB_CONTROL_DB_ATTACH_PERSISTENT
 847                                : CTDB_CONTROL_DB_ATTACH,
 848                                0, 0, data, NULL, &data, &cstatus);
 849         if (!NT_STATUS_IS_OK(status)) {
 850                 DEBUG(0, (__location__ " ctdb_control for db_attach "
 851                           "failed: %s\n", nt_errstr(status)));
 852                 return status;
 853         }
 854
 855         if (cstatus != 0 || data.dsize != sizeof(uint32_t)) {
 856                 DEBUG(0,(__location__ " ctdb_control for db_attach failed\n"));
 857                 return NT_STATUS_INTERNAL_ERROR;
 858         }
 859
 860         *db_id = *(uint32_t *)data.dptr;
 861         talloc_free(data.dptr);
 862
 863         if (!(tdb_flags & TDB_SEQNUM)) {
 864                 return NT_STATUS_OK;
 865         }
 866
 867         data.dptr = (uint8_t *)db_id;
 868         data.dsize = sizeof(*db_id);
 869
 870         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
 871                                CTDB_CONTROL_ENABLE_SEQNUM, 0, 0, data,
 872                                NULL, NULL, &cstatus);
 873         if (!NT_STATUS_IS_OK(status) || cstatus != 0) {
 874                 DEBUG(0,(__location__ " ctdb_control for enable seqnum "
 875                          "failed\n"));
 876                 return NT_STATUS_IS_OK(status) ? NT_STATUS_INTERNAL_ERROR :
 877                         status;
 878         }
 879
 880         return NT_STATUS_OK;
 881 }
 882
 883 /*
 884  * force the migration of a record to this node
 885  */
 886 NTSTATUS ctdbd_migrate(struct ctdbd_connection *conn, uint32 db_id,
 887                        TDB_DATA key)
 888 {
 889         struct ctdb_req_call req;
 890         struct ctdb_reply_call *reply;
 891         NTSTATUS status;
 892
 893         ZERO_STRUCT(req);
 894
 895         req.hdr.length = offsetof(struct ctdb_req_call, data) + key.dsize;
 896         req.hdr.ctdb_magic   = CTDB_MAGIC;
 897         req.hdr.ctdb_version = CTDB_VERSION;
 898         req.hdr.operation    = CTDB_REQ_CALL;
 899         req.hdr.reqid        = ++conn->reqid;
 900         req.flags            = CTDB_IMMEDIATE_MIGRATION;
 901         req.callid           = CTDB_NULL_FUNC;
 902         req.db_id            = db_id;
 903         req.keylen           = key.dsize;
 904
 905         DEBUG(10, ("ctdbd_migrate: Sending ctdb packet\n"));
 906         ctdb_packet_dump(&req.hdr);
 907
 908         status = packet_send(
 909                 conn->pkt, 2,
 910                 data_blob_const(&req, offsetof(struct ctdb_req_call, data)),
 911                 data_blob_const(key.dptr, key.dsize));
 912
 913         if (!NT_STATUS_IS_OK(status)) {
 914                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 915                 return status;
 916         }
 917
 918         status = packet_flush(conn->pkt);
 919
 920         if (!NT_STATUS_IS_OK(status)) {
 921                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 922                 cluster_fatal("cluster dispatch daemon control write error\n");
 923         }
 924
 925         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 926
 927         if (!NT_STATUS_IS_OK(status)) {
 928                 DEBUG(0, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 929                 goto fail;
 930         }
 931
 932         if (reply->hdr.operation != CTDB_REPLY_CALL) {
 933                 DEBUG(0, ("received invalid reply\n"));
 934                 status = NT_STATUS_INTERNAL_ERROR;
 935                 goto fail;
 936         }
 937
 938         status = NT_STATUS_OK;
 939  fail:
 940
 941         TALLOC_FREE(reply);
 942         return status;
 943 }
 944
 945 /*
 946  * remotely fetch a record without locking it or forcing a migration
 947  */
 948 NTSTATUS ctdbd_fetch(struct ctdbd_connection *conn, uint32 db_id,
 949                      TDB_DATA key, TALLOC_CTX *mem_ctx, TDB_DATA *data)
 950 {
 951         struct ctdb_req_call req;
 952         struct ctdb_reply_call *reply;
 953         NTSTATUS status;
 954
 955         ZERO_STRUCT(req);
 956
 957         req.hdr.length = offsetof(struct ctdb_req_call, data) + key.dsize;
 958         req.hdr.ctdb_magic   = CTDB_MAGIC;
 959         req.hdr.ctdb_version = CTDB_VERSION;
 960         req.hdr.operation    = CTDB_REQ_CALL;
 961         req.hdr.reqid        = ++conn->reqid;
 962         req.flags            = 0;
 963         req.callid           = CTDB_FETCH_FUNC;
 964         req.db_id            = db_id;
 965         req.keylen           = key.dsize;
 966
 967         status = packet_send(
 968                 conn->pkt, 2,
 969                 data_blob_const(&req, offsetof(struct ctdb_req_call, data)),
 970                 data_blob_const(key.dptr, key.dsize));
 971
 972         if (!NT_STATUS_IS_OK(status)) {
 973                 DEBUG(3, ("packet_send failed: %s\n", nt_errstr(status)));
 974                 return status;
 975         }
 976
 977         status = packet_flush(conn->pkt);
 978
 979         if (!NT_STATUS_IS_OK(status)) {
 980                 DEBUG(3, ("write to ctdbd failed: %s\n", nt_errstr(status)));
 981                 cluster_fatal("cluster dispatch daemon control write error\n");
 982         }
 983
 984         status = ctdb_read_req(conn, req.hdr.reqid, NULL, (void *)&reply);
 985
 986         if (!NT_STATUS_IS_OK(status)) {
 987                 DEBUG(0, ("ctdb_read_req failed: %s\n", nt_errstr(status)));
 988                 goto fail;
 989         }
 990
 991         if (reply->hdr.operation != CTDB_REPLY_CALL) {
 992                 DEBUG(0, ("received invalid reply\n"));
 993                 status = NT_STATUS_INTERNAL_ERROR;
 994                 goto fail;
 995         }
 996
 997         data->dsize = reply->datalen;
 998         if (data->dsize == 0) {
 999                 data->dptr = NULL;
1000                 goto done;
1001         }
1002
1003         data->dptr = (uint8 *)talloc_memdup(mem_ctx, &reply->data[0],
1004                                             reply->datalen);
1005         if (data->dptr == NULL) {
1006                 DEBUG(0, ("talloc failed\n"));
1007                 status = NT_STATUS_NO_MEMORY;
1008                 goto fail;
1009         }
1010
1011  done:
1012         status = NT_STATUS_OK;
1013  fail:
1014         TALLOC_FREE(reply);
1015         return status;
1016 }
1017
1018 struct ctdbd_traverse_state {
1019         void (*fn)(TDB_DATA key, TDB_DATA data, void *private_data);
1020         void *private_data;
1021 };
1022
1023 /*
1024  * Handle a traverse record coming in on the ctdbd connection
1025  */
1026
1027 static NTSTATUS ctdb_traverse_handler(const struct data_blob *blob,
1028                                       void *private_data)
1029 {
1030         struct ctdbd_traverse_state *state =
1031                 (struct ctdbd_traverse_state *)private_data;
1032
1033         struct ctdb_req_message *m;
1034         struct ctdb_rec_data *d;
1035         TDB_DATA key, data;
1036
1037         m = (struct ctdb_req_message *)blob->data;
1038
1039         if (blob->length < sizeof(*m) || m->hdr.length != blob->length) {
1040                 DEBUG(0, ("Got invalid message of length %d\n",
1041                           (int)blob->length));
1042                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1043         }
1044
1045         d = (struct ctdb_rec_data *)&m->data[0];
1046         if (m->datalen < sizeof(uint32_t) || m->datalen != d->length) {
1047                 DEBUG(0, ("Got invalid traverse data of length %d\n",
1048                           (int)m->datalen));
1049                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1050         }
1051
1052         key.dsize = d->keylen;
1053         key.dptr  = &d->data[0];
1054         data.dsize = d->datalen;
1055         data.dptr = &d->data[d->keylen];
1056
1057         if (key.dsize == 0 && data.dsize == 0) {
1058                 /* end of traverse */
1059                 return NT_STATUS_END_OF_FILE;
1060         }
1061
1062         if (data.dsize < sizeof(struct ctdb_ltdb_header)) {
1063                 DEBUG(0, ("Got invalid ltdb header length %d\n",
1064                           (int)data.dsize));
1065                 return NT_STATUS_UNEXPECTED_IO_ERROR;
1066         }
1067         data.dsize -= sizeof(struct ctdb_ltdb_header);
1068         data.dptr += sizeof(struct ctdb_ltdb_header);
1069
1070         if (state->fn) {
1071                 state->fn(key, data, state->private_data);
1072         }
1073
1074         return NT_STATUS_OK;
1075 }
1076
1077 /*
1078   Traverse a ctdb database. This uses a kind-of hackish way to open a second
1079   connection to ctdbd to avoid the hairy recursive and async problems with
1080   everything in-line.
1081 */
1082
1083 NTSTATUS ctdbd_traverse(uint32 db_id,
1084                         void (*fn)(TDB_DATA key, TDB_DATA data,
1085                                    void *private_data),
1086                         void *private_data)
1087 {
1088         struct ctdbd_connection *conn;
1089         NTSTATUS status;
1090
1091         TDB_DATA data;
1092         struct ctdb_traverse_start t;
1093         int cstatus;
1094         struct ctdbd_traverse_state state;
1095
1096         status = ctdbd_init_connection(NULL, &conn);
1097         if (!NT_STATUS_IS_OK(status)) {
1098                 DEBUG(0, ("ctdbd_init_connection failed: %s\n",
1099                           nt_errstr(status)));
1100                 return status;
1101         }
1102
1103         t.db_id = db_id;
1104         t.srvid = conn->rand_srvid;
1105         t.reqid = ++conn->reqid;
1106
1107         data.dptr = (uint8_t *)&t;
1108         data.dsize = sizeof(t);
1109
1110         status = ctdbd_control(conn, CTDB_CURRENT_NODE,
1111                                CTDB_CONTROL_TRAVERSE_START, conn->rand_srvid, 0,
1112                                data, NULL, NULL, &cstatus);
1113
1114         if (!NT_STATUS_IS_OK(status) || (cstatus != 0)) {
1115
1116                 DEBUG(0,("ctdbd_control failed: %s, %d\n", nt_errstr(status),
1117                          cstatus));
1118
1119                 if (NT_STATUS_IS_OK(status)) {
1120                         /*
1121                          * We need a mapping here
1122                          */
1123                         status = NT_STATUS_UNSUCCESSFUL;
1124                 }
1125                 goto done;
1126         }
1127
1128         state.fn = fn;
1129         state.private_data = private_data;
1130
1131         while (True) {
1132
1133                 status = NT_STATUS_OK;
1134
1135                 if (packet_handler(conn->pkt, ctdb_req_complete,
1136                                    ctdb_traverse_handler, &state, &status)) {
1137
1138                         if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
1139                                 status = NT_STATUS_OK;
1140                                 break;
1141                         }
1142
1143                         /*
1144                          * There might be more in the queue
1145                          */
1146                         continue;
1147                 }
1148
1149                 if (!NT_STATUS_IS_OK(status)) {
1150                         break;
1151                 }
1152
1153                 status = packet_fd_read_sync(conn->pkt);
1154
1155                 if (NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
1156                         /*
1157                          * There might be more in the queue
1158                          */
1159                         continue;
1160                 }
1161
1162                 if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
1163                         status = NT_STATUS_OK;
1164                 }
1165
1166                 if (!NT_STATUS_IS_OK(status)) {
1167                         DEBUG(0, ("packet_fd_read_sync failed: %s\n", nt_errstr(status)));
1168                         cluster_fatal("ctdbd died\n");
1169                 }
1170         }
1171
1172  done:
1173         TALLOC_FREE(conn);
1174         return status;
1175 }
1176
1177 /*
1178    This is used to canonicalize a ctdb_sock_addr structure.
1179 */
1180 static void smbd_ctdb_canonicalize_ip(const struct sockaddr_storage *in,
1181                                       struct sockaddr_storage *out)
1182 {
1183         memcpy(out, in, sizeof (*out));
1184
1185 #ifdef HAVE_IPV6
1186         if (in->ss_family == AF_INET6) {
1187                 const char prefix[12] = { 0,0,0,0,0,0,0,0,0,0,0xff,0xff };
1188                 const struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)in;
1189                 struct sockaddr_in *out4 = (struct sockaddr_in *)out;
1190                 if (memcmp(&in6->sin6_addr, prefix, 12) == 0) {
1191                         memset(out, 0, sizeof(*out));
1192 #ifdef HAVE_SOCK_SIN_LEN
1193                         out4->sin_len = sizeof(*out);
1194 #endif
1195                         out4->sin_family = AF_INET;
1196                         out4->sin_port   = in6->sin6_port;
1197                         memcpy(&out4->sin_addr, &in6->sin6_addr.s6_addr32[3], 4);
1198                 }
1199         }
1200 #endif
1201 }
1202
1203 /*
1204  * Register us as a server for a particular tcp connection
1205  */
1206
1207 NTSTATUS ctdbd_register_ips(struct ctdbd_connection *conn,
1208                             const struct sockaddr_storage *_server,
1209                             const struct sockaddr_storage *_client,
1210                             void (*release_ip_handler)(const char *ip_addr,
1211                                                        void *private_data),
1212                             void *private_data)
1213 {
1214         /*
1215          * we still use ctdb_control_tcp for ipv4
1216          * because we want to work against older ctdb
1217          * versions at runtime
1218          */
1219         struct ctdb_control_tcp p4;
1220 #ifdef HAVE_STRUCT_CTDB_CONTROL_TCP_ADDR
1221         struct ctdb_control_tcp_addr p;
1222 #endif
1223         TDB_DATA data;
1224         NTSTATUS status;
1225         struct sockaddr_storage client;
1226         struct sockaddr_storage server;
1227
1228         /*
1229          * Only one connection so far
1230          */
1231         SMB_ASSERT(conn->release_ip_handler == NULL);
1232
1233         smbd_ctdb_canonicalize_ip(_client, &client);
1234         smbd_ctdb_canonicalize_ip(_server, &server);
1235
1236         switch (client.ss_family) {
1237         case AF_INET:
1238                 p4.dest = *(struct sockaddr_in *)&server;
1239                 p4.src = *(struct sockaddr_in *)&client;
1240                 data.dptr = (uint8_t *)&p4;
1241                 data.dsize = sizeof(p4);
1242                 break;
1243 #ifdef HAVE_STRUCT_CTDB_CONTROL_TCP_ADDR
1244         case AF_INET6:
1245                 p.dest.ip6 = *(struct sockaddr_in6 *)&server;
1246                 p.src.ip6 = *(struct sockaddr_in6 *)&client;
1247                 data.dptr = (uint8_t *)&p;
1248                 data.dsize = sizeof(p);
1249                 break;
1250 #endif
1251         default:
1252                 return NT_STATUS_INTERNAL_ERROR;
1253         }
1254
1255         conn->release_ip_handler = release_ip_handler;
1256
1257         /*
1258          * We want to be told about IP releases
1259          */
1260
1261         status = register_with_ctdbd(conn, CTDB_SRVID_RELEASE_IP);
1262         if (!NT_STATUS_IS_OK(status)) {
1263                 return status;
1264         }
1265
1266         /*
1267          * inform ctdb of our tcp connection, so if IP takeover happens ctdb
1268          * can send an extra ack to trigger a reset for our client, so it
1269          * immediately reconnects
1270          */
1271         return ctdbd_control(conn, CTDB_CURRENT_NODE,
1272                              CTDB_CONTROL_TCP_CLIENT, 0,
1273                              CTDB_CTRL_FLAG_NOREPLY, data, NULL, NULL, NULL);
1274 }
1275
1276 /*
1277  * We want to handle reconfigure events
1278  */
1279 NTSTATUS ctdbd_register_reconfigure(struct ctdbd_connection *conn)
1280 {
1281         return register_with_ctdbd(conn, CTDB_SRVID_RECONFIGURE);
1282 }
1283
1284 /*
1285   call a control on the local node
1286  */
1287 NTSTATUS ctdbd_control_local(struct ctdbd_connection *conn, uint32 opcode,
1288                              uint64_t srvid, uint32_t flags, TDB_DATA data,
1289                              TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
1290                              int *cstatus)
1291 {
1292         return ctdbd_control(conn, CTDB_CURRENT_NODE, opcode, srvid, flags, data, mem_ctx, outdata, cstatus);
1293 }
1294
1295 #else
1296
1297 NTSTATUS ctdbd_init_connection(TALLOC_CTX *mem_ctx,
1298                                struct ctdbd_connection **pconn)
1299 {
1300         return NT_STATUS_NOT_IMPLEMENTED;
1301 }
1302
1303 #endif