root/source4/lib/messaging/messaging.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. ping_message
  2. irpc_uptime
  3. messaging_path
  4. messaging_dispatch
  5. cluster_message_handler
  6. try_send
  7. msg_retry_timer
  8. messaging_send_handler
  9. messaging_recv_handler
  10. messaging_handler
  11. messaging_register
  12. messaging_register_tmp
  13. messaging_deregister
  14. messaging_send
  15. messaging_send_ptr
  16. messaging_destructor
  17. messaging_init
  18. messaging_client_init
  19. irpc_register
  20. irpc_handler_reply
  21. irpc_send_reply
  22. irpc_handler_request
  23. irpc_handler
  24. irpc_destructor
  25. irpc_timeout
  26. irpc_call_send
  27. irpc_call_recv
  28. irpc_call
  29. irpc_namedb_open
  30. irpc_add_name
  31. irpc_servers_byname
  32. irpc_remove_name
  33. messaging_get_server_id

   1 /* 
   2    Unix SMB/CIFS implementation.
   3 
   4    Samba internal messaging functions
   5 
   6    Copyright (C) Andrew Tridgell 2004
   7    
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12    
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17    
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21 
  22 #include "includes.h"
  23 #include "lib/events/events.h"
  24 #include "system/filesys.h"
  25 #include "messaging/messaging.h"
  26 #include "../lib/util/dlinklist.h"
  27 #include "lib/socket/socket.h"
  28 #include "librpc/gen_ndr/ndr_irpc.h"
  29 #include "lib/messaging/irpc.h"
  30 #include "tdb_wrap.h"
  31 #include "../lib/util/unix_privs.h"
  32 #include "librpc/rpc/dcerpc.h"
  33 #include "../tdb/include/tdb.h"
  34 #include "../lib/util/util_tdb.h"
  35 #include "cluster/cluster.h"
  36 
  37 /* change the message version with any incompatible changes in the protocol */
  38 #define MESSAGING_VERSION 1
  39 
  40 struct messaging_context {
  41         struct server_id server_id;
  42         struct socket_context *sock;
  43         const char *base_path;
  44         const char *path;
  45         struct dispatch_fn **dispatch;
  46         uint32_t num_types;
  47         struct idr_context *dispatch_tree;
  48         struct messaging_rec *pending;
  49         struct messaging_rec *retry_queue;
  50         struct smb_iconv_convenience *iconv_convenience;
  51         struct irpc_list *irpc;
  52         struct idr_context *idr;
  53         const char **names;
  54         struct timeval start_time;
  55         struct tevent_timer *retry_te;
  56         struct {
  57                 struct tevent_context *ev;
  58                 struct tevent_fd *fde;
  59         } event;
  60 };
  61 
  62 /* we have a linked list of dispatch handlers for each msg_type that
  63    this messaging server can deal with */
  64 struct dispatch_fn {
  65         struct dispatch_fn *next, *prev;
  66         uint32_t msg_type;
  67         void *private_data;
  68         msg_callback_t fn;
  69 };
  70 
  71 /* an individual message */
  72 struct messaging_rec {
  73         struct messaging_rec *next, *prev;
  74         struct messaging_context *msg;
  75         const char *path;
  76 
  77         struct messaging_header {
  78                 uint32_t version;
  79                 uint32_t msg_type;
  80                 struct server_id from;
  81                 struct server_id to;
  82                 uint32_t length;
  83         } *header;
  84 
  85         DATA_BLOB packet;
  86         uint32_t retries;
  87 };
  88 
  89 
  90 static void irpc_handler(struct messaging_context *, void *, 
  91                          uint32_t, struct server_id, DATA_BLOB *);
  92 
  93 
  94 /*
  95  A useful function for testing the message system.
  96 */
  97 static void ping_message(struct messaging_context *msg, void *private_data,
     /* [<][>][^][v][top][bottom][index][help] */
  98                          uint32_t msg_type, struct server_id src, DATA_BLOB *data)
  99 {
 100         DEBUG(1,("INFO: Received PING message from server %u.%u [%.*s]\n",
 101                  (uint_t)src.node, (uint_t)src.id, (int)data->length, 
 102                  data->data?(const char *)data->data:""));
 103         messaging_send(msg, src, MSG_PONG, data);
 104 }
 105 
 106 /*
 107   return uptime of messaging server via irpc
 108 */
 109 static NTSTATUS irpc_uptime(struct irpc_message *msg, 
     /* [<][>][^][v][top][bottom][index][help] */
 110                             struct irpc_uptime *r)
 111 {
 112         struct messaging_context *ctx = talloc_get_type(msg->private_data, struct messaging_context);
 113         *r->out.start_time = timeval_to_nttime(&ctx->start_time);
 114         return NT_STATUS_OK;
 115 }
 116 
 117 /* 
 118    return the path to a messaging socket
 119 */
 120 static char *messaging_path(struct messaging_context *msg, struct server_id server_id)
     /* [<][>][^][v][top][bottom][index][help] */
 121 {
 122         return talloc_asprintf(msg, "%s/msg.%s", msg->base_path, 
 123                                cluster_id_string(msg, server_id));
 124 }
 125 
 126 /*
 127   dispatch a fully received message
 128 
 129   note that this deliberately can match more than one message handler
 130   per message. That allows a single messasging context to register
 131   (for example) a debug handler for more than one piece of code
 132 */
 133 static void messaging_dispatch(struct messaging_context *msg, struct messaging_rec *rec)
     /* [<][>][^][v][top][bottom][index][help] */
 134 {
 135         struct dispatch_fn *d, *next;
 136 
 137         /* temporary IDs use an idtree, the rest use a array of pointers */
 138         if (rec->header->msg_type >= MSG_TMP_BASE) {
 139                 d = (struct dispatch_fn *)idr_find(msg->dispatch_tree, 
 140                                                    rec->header->msg_type);
 141         } else if (rec->header->msg_type < msg->num_types) {
 142                 d = msg->dispatch[rec->header->msg_type];
 143         } else {
 144                 d = NULL;
 145         }
 146 
 147         for (; d; d = next) {
 148                 DATA_BLOB data;
 149                 next = d->next;
 150                 data.data = rec->packet.data + sizeof(*rec->header);
 151                 data.length = rec->header->length;
 152                 d->fn(msg, d->private_data, d->msg_type, rec->header->from, &data);
 153         }
 154         rec->header->length = 0;
 155 }
 156 
 157 /*
 158   handler for messages that arrive from other nodes in the cluster
 159 */
 160 static void cluster_message_handler(struct messaging_context *msg, DATA_BLOB packet)
     /* [<][>][^][v][top][bottom][index][help] */
 161 {
 162         struct messaging_rec *rec;
 163 
 164         rec = talloc(msg, struct messaging_rec);
 165         if (rec == NULL) {
 166                 smb_panic("Unable to allocate messaging_rec");
 167         }
 168 
 169         rec->msg           = msg;
 170         rec->path          = msg->path;
 171         rec->header        = (struct messaging_header *)packet.data;
 172         rec->packet        = packet;
 173         rec->retries       = 0;
 174 
 175         if (packet.length != sizeof(*rec->header) + rec->header->length) {
 176                 DEBUG(0,("messaging: bad message header size %d should be %d\n", 
 177                          rec->header->length, (int)(packet.length - sizeof(*rec->header))));
 178                 talloc_free(rec);
 179                 return;
 180         }
 181 
 182         messaging_dispatch(msg, rec);
 183         talloc_free(rec);
 184 }
 185 
 186 
 187 
 188 /*
 189   try to send the message
 190 */
 191 static NTSTATUS try_send(struct messaging_rec *rec)
     /* [<][>][^][v][top][bottom][index][help] */
 192 {
 193         struct messaging_context *msg = rec->msg;
 194         size_t nsent;
 195         void *priv;
 196         NTSTATUS status;
 197         struct socket_address *path;
 198 
 199         /* rec->path is the path of the *other* socket, where we want
 200          * this to end up */
 201         path = socket_address_from_strings(msg, msg->sock->backend_name, 
 202                                            rec->path, 0);
 203         if (!path) {
 204                 return NT_STATUS_NO_MEMORY;
 205         }
 206 
 207         /* we send with privileges so messages work from any context */
 208         priv = root_privileges();
 209         status = socket_sendto(msg->sock, &rec->packet, &nsent, path);
 210         talloc_free(path);
 211         talloc_free(priv);
 212 
 213         return status;
 214 }
 215 
 216 /*
 217   retry backed off messages
 218 */
 219 static void msg_retry_timer(struct tevent_context *ev, struct tevent_timer *te, 
     /* [<][>][^][v][top][bottom][index][help] */
 220                             struct timeval t, void *private_data)
 221 {
 222         struct messaging_context *msg = talloc_get_type(private_data,
 223                                                         struct messaging_context);
 224         msg->retry_te = NULL;
 225 
 226         /* put the messages back on the main queue */
 227         while (msg->retry_queue) {
 228                 struct messaging_rec *rec = msg->retry_queue;
 229                 DLIST_REMOVE(msg->retry_queue, rec);
 230                 DLIST_ADD_END(msg->pending, rec, struct messaging_rec *);
 231         }
 232 
 233         EVENT_FD_WRITEABLE(msg->event.fde);     
 234 }
 235 
 236 /*
 237   handle a socket write event
 238 */
 239 static void messaging_send_handler(struct messaging_context *msg)
     /* [<][>][^][v][top][bottom][index][help] */
 240 {
 241         while (msg->pending) {
 242                 struct messaging_rec *rec = msg->pending;
 243                 NTSTATUS status;
 244                 status = try_send(rec);
 245                 if (NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) {
 246                         rec->retries++;
 247                         if (rec->retries > 3) {
 248                                 /* we're getting continuous write errors -
 249                                    backoff this record */
 250                                 DLIST_REMOVE(msg->pending, rec);
 251                                 DLIST_ADD_END(msg->retry_queue, rec, 
 252                                               struct messaging_rec *);
 253                                 if (msg->retry_te == NULL) {
 254                                         msg->retry_te = 
 255                                                 event_add_timed(msg->event.ev, msg, 
 256                                                                 timeval_current_ofs(1, 0), 
 257                                                                 msg_retry_timer, msg);
 258                                 }
 259                         }
 260                         break;
 261                 }
 262                 rec->retries = 0;
 263                 if (!NT_STATUS_IS_OK(status)) {
 264                         DEBUG(1,("messaging: Lost message from %s to %s of type %u - %s\n", 
 265                                  cluster_id_string(debug_ctx(), rec->header->from), 
 266                                  cluster_id_string(debug_ctx(), rec->header->to), 
 267                                  rec->header->msg_type, 
 268                                  nt_errstr(status)));
 269                 }
 270                 DLIST_REMOVE(msg->pending, rec);
 271                 talloc_free(rec);
 272         }
 273         if (msg->pending == NULL) {
 274                 EVENT_FD_NOT_WRITEABLE(msg->event.fde);
 275         }
 276 }
 277 
 278 /*
 279   handle a new incoming packet
 280 */
 281 static void messaging_recv_handler(struct messaging_context *msg)
     /* [<][>][^][v][top][bottom][index][help] */
 282 {
 283         struct messaging_rec *rec;
 284         NTSTATUS status;
 285         DATA_BLOB packet;
 286         size_t msize;
 287 
 288         /* see how many bytes are in the next packet */
 289         status = socket_pending(msg->sock, &msize);
 290         if (!NT_STATUS_IS_OK(status)) {
 291                 DEBUG(0,("socket_pending failed in messaging - %s\n", 
 292                          nt_errstr(status)));
 293                 return;
 294         }
 295         
 296         packet = data_blob_talloc(msg, NULL, msize);
 297         if (packet.data == NULL) {
 298                 /* assume this is temporary and retry */
 299                 return;
 300         }
 301             
 302         status = socket_recv(msg->sock, packet.data, msize, &msize);
 303         if (!NT_STATUS_IS_OK(status)) {
 304                 data_blob_free(&packet);
 305                 return;
 306         }
 307 
 308         if (msize < sizeof(*rec->header)) {
 309                 DEBUG(0,("messaging: bad message of size %d\n", (int)msize));
 310                 data_blob_free(&packet);
 311                 return;
 312         }
 313 
 314         rec = talloc(msg, struct messaging_rec);
 315         if (rec == NULL) {
 316                 smb_panic("Unable to allocate messaging_rec");
 317         }
 318 
 319         talloc_steal(rec, packet.data);
 320         rec->msg           = msg;
 321         rec->path          = msg->path;
 322         rec->header        = (struct messaging_header *)packet.data;
 323         rec->packet        = packet;
 324         rec->retries       = 0;
 325 
 326         if (msize != sizeof(*rec->header) + rec->header->length) {
 327                 DEBUG(0,("messaging: bad message header size %d should be %d\n", 
 328                          rec->header->length, (int)(msize - sizeof(*rec->header))));
 329                 talloc_free(rec);
 330                 return;
 331         }
 332 
 333         messaging_dispatch(msg, rec);
 334         talloc_free(rec);
 335 }
 336 
 337 
 338 /*
 339   handle a socket event
 340 */
 341 static void messaging_handler(struct tevent_context *ev, struct tevent_fd *fde, 
     /* [<][>][^][v][top][bottom][index][help] */
 342                               uint16_t flags, void *private_data)
 343 {
 344         struct messaging_context *msg = talloc_get_type(private_data,
 345                                                         struct messaging_context);
 346         if (flags & EVENT_FD_WRITE) {
 347                 messaging_send_handler(msg);
 348         }
 349         if (flags & EVENT_FD_READ) {
 350                 messaging_recv_handler(msg);
 351         }
 352 }
 353 
 354 
 355 /*
 356   Register a dispatch function for a particular message type.
 357 */
 358 NTSTATUS messaging_register(struct messaging_context *msg, void *private_data,
     /* [<][>][^][v][top][bottom][index][help] */
 359                             uint32_t msg_type, msg_callback_t fn)
 360 {
 361         struct dispatch_fn *d;
 362 
 363         /* possibly expand dispatch array */
 364         if (msg_type >= msg->num_types) {
 365                 struct dispatch_fn **dp;
 366                 int i;
 367                 dp = talloc_realloc(msg, msg->dispatch, struct dispatch_fn *, msg_type+1);
 368                 NT_STATUS_HAVE_NO_MEMORY(dp);
 369                 msg->dispatch = dp;
 370                 for (i=msg->num_types;i<=msg_type;i++) {
 371                         msg->dispatch[i] = NULL;
 372                 }
 373                 msg->num_types = msg_type+1;
 374         }
 375 
 376         d = talloc_zero(msg->dispatch, struct dispatch_fn);
 377         NT_STATUS_HAVE_NO_MEMORY(d);
 378         d->msg_type = msg_type;
 379         d->private_data = private_data;
 380         d->fn = fn;
 381 
 382         DLIST_ADD(msg->dispatch[msg_type], d);
 383 
 384         return NT_STATUS_OK;
 385 }
 386 
 387 /*
 388   register a temporary message handler. The msg_type is allocated
 389   above MSG_TMP_BASE
 390 */
 391 NTSTATUS messaging_register_tmp(struct messaging_context *msg, void *private_data,
     /* [<][>][^][v][top][bottom][index][help] */
 392                                 msg_callback_t fn, uint32_t *msg_type)
 393 {
 394         struct dispatch_fn *d;
 395         int id;
 396 
 397         d = talloc_zero(msg->dispatch, struct dispatch_fn);
 398         NT_STATUS_HAVE_NO_MEMORY(d);
 399         d->private_data = private_data;
 400         d->fn = fn;
 401 
 402         id = idr_get_new_above(msg->dispatch_tree, d, MSG_TMP_BASE, UINT16_MAX);
 403         if (id == -1) {
 404                 talloc_free(d);
 405                 return NT_STATUS_TOO_MANY_CONTEXT_IDS;
 406         }
 407 
 408         d->msg_type = (uint32_t)id;
 409         (*msg_type) = d->msg_type;
 410 
 411         return NT_STATUS_OK;
 412 }
 413 
 414 /*
 415   De-register the function for a particular message type.
 416 */
 417 void messaging_deregister(struct messaging_context *msg, uint32_t msg_type, void *private_data)
     /* [<][>][^][v][top][bottom][index][help] */
 418 {
 419         struct dispatch_fn *d, *next;
 420 
 421         if (msg_type >= msg->num_types) {
 422                 d = (struct dispatch_fn *)idr_find(msg->dispatch_tree, 
 423                                                    msg_type);
 424                 if (!d) return;
 425                 idr_remove(msg->dispatch_tree, msg_type);
 426                 talloc_free(d);
 427                 return;
 428         }
 429 
 430         for (d = msg->dispatch[msg_type]; d; d = next) {
 431                 next = d->next;
 432                 if (d->private_data == private_data) {
 433                         DLIST_REMOVE(msg->dispatch[msg_type], d);
 434                         talloc_free(d);
 435                 }
 436         }
 437 }
 438 
 439 /*
 440   Send a message to a particular server
 441 */
 442 NTSTATUS messaging_send(struct messaging_context *msg, struct server_id server, 
     /* [<][>][^][v][top][bottom][index][help] */
 443                         uint32_t msg_type, DATA_BLOB *data)
 444 {
 445         struct messaging_rec *rec;
 446         NTSTATUS status;
 447         size_t dlength = data?data->length:0;
 448 
 449         rec = talloc(msg, struct messaging_rec);
 450         if (rec == NULL) {
 451                 return NT_STATUS_NO_MEMORY;
 452         }
 453 
 454         rec->packet = data_blob_talloc(rec, NULL, sizeof(*rec->header) + dlength);
 455         if (rec->packet.data == NULL) {
 456                 talloc_free(rec);
 457                 return NT_STATUS_NO_MEMORY;
 458         }
 459 
 460         rec->retries       = 0;
 461         rec->msg              = msg;
 462         rec->header           = (struct messaging_header *)rec->packet.data;
 463         /* zero padding */
 464         ZERO_STRUCTP(rec->header);
 465         rec->header->version  = MESSAGING_VERSION;
 466         rec->header->msg_type = msg_type;
 467         rec->header->from     = msg->server_id;
 468         rec->header->to       = server;
 469         rec->header->length   = dlength;
 470         if (dlength != 0) {
 471                 memcpy(rec->packet.data + sizeof(*rec->header), 
 472                        data->data, dlength);
 473         }
 474 
 475         if (!cluster_node_equal(&msg->server_id, &server)) {
 476                 /* the destination is on another node - dispatch via
 477                    the cluster layer */
 478                 status = cluster_message_send(server, &rec->packet);
 479                 talloc_free(rec);
 480                 return status;
 481         }
 482 
 483         rec->path = messaging_path(msg, server);
 484         talloc_steal(rec, rec->path);
 485 
 486         if (msg->pending != NULL) {
 487                 status = STATUS_MORE_ENTRIES;
 488         } else {
 489                 status = try_send(rec);
 490         }
 491 
 492         if (NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) {
 493                 if (msg->pending == NULL) {
 494                         EVENT_FD_WRITEABLE(msg->event.fde);
 495                 }
 496                 DLIST_ADD_END(msg->pending, rec, struct messaging_rec *);
 497                 return NT_STATUS_OK;
 498         }
 499 
 500         talloc_free(rec);
 501 
 502         return status;
 503 }
 504 
 505 /*
 506   Send a message to a particular server, with the message containing a single pointer
 507 */
 508 NTSTATUS messaging_send_ptr(struct messaging_context *msg, struct server_id server, 
     /* [<][>][^][v][top][bottom][index][help] */
 509                             uint32_t msg_type, void *ptr)
 510 {
 511         DATA_BLOB blob;
 512 
 513         blob.data = (uint8_t *)&ptr;
 514         blob.length = sizeof(void *);
 515 
 516         return messaging_send(msg, server, msg_type, &blob);
 517 }
 518 
 519 
 520 /*
 521   destroy the messaging context
 522 */
 523 static int messaging_destructor(struct messaging_context *msg)
     /* [<][>][^][v][top][bottom][index][help] */
 524 {
 525         unlink(msg->path);
 526         while (msg->names && msg->names[0]) {
 527                 irpc_remove_name(msg, msg->names[0]);
 528         }
 529         return 0;
 530 }
 531 
 532 /*
 533   create the listening socket and setup the dispatcher
 534 */
 535 struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx, 
     /* [<][>][^][v][top][bottom][index][help] */
 536                                          const char *dir,
 537                                          struct server_id server_id, 
 538                                          struct smb_iconv_convenience *iconv_convenience,
 539                                          struct tevent_context *ev)
 540 {
 541         struct messaging_context *msg;
 542         NTSTATUS status;
 543         struct socket_address *path;
 544 
 545         if (ev == NULL) {
 546                 return NULL;
 547         }
 548 
 549         msg = talloc_zero(mem_ctx, struct messaging_context);
 550         if (msg == NULL) {
 551                 return NULL;
 552         }
 553 
 554         /* setup a handler for messages from other cluster nodes, if appropriate */
 555         status = cluster_message_init(msg, server_id, cluster_message_handler);
 556         if (!NT_STATUS_IS_OK(status)) {
 557                 talloc_free(msg);
 558                 return NULL;
 559         }
 560 
 561         /* create the messaging directory if needed */
 562         mkdir(dir, 0700);
 563 
 564         msg->base_path     = talloc_reference(msg, dir);
 565         msg->path          = messaging_path(msg, server_id);
 566         msg->server_id     = server_id;
 567         msg->iconv_convenience = iconv_convenience;
 568         msg->idr           = idr_init(msg);
 569         msg->dispatch_tree = idr_init(msg);
 570         msg->start_time    = timeval_current();
 571 
 572         status = socket_create("unix", SOCKET_TYPE_DGRAM, &msg->sock, 0);
 573         if (!NT_STATUS_IS_OK(status)) {
 574                 talloc_free(msg);
 575                 return NULL;
 576         }
 577 
 578         /* by stealing here we ensure that the socket is cleaned up (and even 
 579            deleted) on exit */
 580         talloc_steal(msg, msg->sock);
 581 
 582         path = socket_address_from_strings(msg, msg->sock->backend_name, 
 583                                            msg->path, 0);
 584         if (!path) {
 585                 talloc_free(msg);
 586                 return NULL;
 587         }
 588 
 589         status = socket_listen(msg->sock, path, 50, 0);
 590         if (!NT_STATUS_IS_OK(status)) {
 591                 DEBUG(0,("Unable to setup messaging listener for '%s':%s\n", msg->path, nt_errstr(status)));
 592                 talloc_free(msg);
 593                 return NULL;
 594         }
 595 
 596         /* it needs to be non blocking for sends */
 597         set_blocking(socket_get_fd(msg->sock), false);
 598 
 599         msg->event.ev   = talloc_reference(msg, ev);
 600         msg->event.fde  = event_add_fd(ev, msg, socket_get_fd(msg->sock), 
 601                                        EVENT_FD_READ, messaging_handler, msg);
 602 
 603         talloc_set_destructor(msg, messaging_destructor);
 604         
 605         messaging_register(msg, NULL, MSG_PING, ping_message);
 606         messaging_register(msg, NULL, MSG_IRPC, irpc_handler);
 607         IRPC_REGISTER(msg, irpc, IRPC_UPTIME, irpc_uptime, msg);
 608 
 609         return msg;
 610 }
 611 
 612 /* 
 613    A hack, for the short term until we get 'client only' messaging in place 
 614 */
 615 struct messaging_context *messaging_client_init(TALLOC_CTX *mem_ctx, 
     /* [<][>][^][v][top][bottom][index][help] */
 616                                                 const char *dir,
 617                                                 struct smb_iconv_convenience *iconv_convenience,
 618                                                 struct tevent_context *ev)
 619 {
 620         struct server_id id;
 621         ZERO_STRUCT(id);
 622         id.id = random() % 0x10000000;
 623         return messaging_init(mem_ctx, dir, id, iconv_convenience, ev);
 624 }
 625 /*
 626   a list of registered irpc server functions
 627 */
 628 struct irpc_list {
 629         struct irpc_list *next, *prev;
 630         struct GUID uuid;
 631         const struct ndr_interface_table *table;
 632         int callnum;
 633         irpc_function_t fn;
 634         void *private_data;
 635 };
 636 
 637 
 638 /*
 639   register a irpc server function
 640 */
 641 NTSTATUS irpc_register(struct messaging_context *msg_ctx, 
     /* [<][>][^][v][top][bottom][index][help] */
 642                        const struct ndr_interface_table *table, 
 643                        int callnum, irpc_function_t fn, void *private_data)
 644 {
 645         struct irpc_list *irpc;
 646 
 647         /* override an existing handler, if any */
 648         for (irpc=msg_ctx->irpc; irpc; irpc=irpc->next) {
 649                 if (irpc->table == table && irpc->callnum == callnum) {
 650                         break;
 651                 }
 652         }
 653         if (irpc == NULL) {
 654                 irpc = talloc(msg_ctx, struct irpc_list);
 655                 NT_STATUS_HAVE_NO_MEMORY(irpc);
 656                 DLIST_ADD(msg_ctx->irpc, irpc);
 657         }
 658 
 659         irpc->table   = table;
 660         irpc->callnum = callnum;
 661         irpc->fn      = fn;
 662         irpc->private_data = private_data;
 663         irpc->uuid = irpc->table->syntax_id.uuid;
 664 
 665         return NT_STATUS_OK;
 666 }
 667 
 668 
 669 /*
 670   handle an incoming irpc reply message
 671 */
 672 static void irpc_handler_reply(struct messaging_context *msg_ctx, struct irpc_message *m)
     /* [<][>][^][v][top][bottom][index][help] */
 673 {
 674         struct irpc_request *irpc;
 675         enum ndr_err_code ndr_err;
 676 
 677         irpc = (struct irpc_request *)idr_find(msg_ctx->idr, m->header.callid);
 678         if (irpc == NULL) return;
 679 
 680         /* parse the reply data */
 681         ndr_err = irpc->table->calls[irpc->callnum].ndr_pull(m->ndr, NDR_OUT, irpc->r);
 682         if (NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 683                 irpc->status = m->header.status;
 684                 talloc_steal(irpc->mem_ctx, m);
 685         } else {
 686                 irpc->status = ndr_map_error2ntstatus(ndr_err);
 687                 talloc_steal(irpc, m);
 688         }
 689         irpc->done = true;
 690         if (irpc->async.fn) {
 691                 irpc->async.fn(irpc);
 692         }
 693 }
 694 
 695 /*
 696   send a irpc reply
 697 */
 698 NTSTATUS irpc_send_reply(struct irpc_message *m, NTSTATUS status)
     /* [<][>][^][v][top][bottom][index][help] */
 699 {
 700         struct ndr_push *push;
 701         DATA_BLOB packet;
 702         enum ndr_err_code ndr_err;
 703 
 704         m->header.status = status;
 705 
 706         /* setup the reply */
 707         push = ndr_push_init_ctx(m->ndr, m->msg_ctx->iconv_convenience);
 708         if (push == NULL) {
 709                 status = NT_STATUS_NO_MEMORY;
 710                 goto failed;
 711         }
 712 
 713         m->header.flags |= IRPC_FLAG_REPLY;
 714 
 715         /* construct the packet */
 716         ndr_err = ndr_push_irpc_header(push, NDR_SCALARS|NDR_BUFFERS, &m->header);
 717         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 718                 status = ndr_map_error2ntstatus(ndr_err);
 719                 goto failed;
 720         }
 721 
 722         ndr_err = m->irpc->table->calls[m->irpc->callnum].ndr_push(push, NDR_OUT, m->data);
 723         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 724                 status = ndr_map_error2ntstatus(ndr_err);
 725                 goto failed;
 726         }
 727 
 728         /* send the reply message */
 729         packet = ndr_push_blob(push);
 730         status = messaging_send(m->msg_ctx, m->from, MSG_IRPC, &packet);
 731         if (!NT_STATUS_IS_OK(status)) goto failed;
 732 
 733 failed:
 734         talloc_free(m);
 735         return status;
 736 }
 737 
 738 /*
 739   handle an incoming irpc request message
 740 */
 741 static void irpc_handler_request(struct messaging_context *msg_ctx, 
     /* [<][>][^][v][top][bottom][index][help] */
 742                                  struct irpc_message *m)
 743 {
 744         struct irpc_list *i;
 745         void *r;
 746         enum ndr_err_code ndr_err;
 747 
 748         for (i=msg_ctx->irpc; i; i=i->next) {
 749                 if (GUID_equal(&i->uuid, &m->header.uuid) &&
 750                     i->table->syntax_id.if_version == m->header.if_version &&
 751                     i->callnum == m->header.callnum) {
 752                         break;
 753                 }
 754         }
 755 
 756         if (i == NULL) {
 757                 /* no registered handler for this message */
 758                 talloc_free(m);
 759                 return;
 760         }
 761 
 762         /* allocate space for the structure */
 763         r = talloc_zero_size(m->ndr, i->table->calls[m->header.callnum].struct_size);
 764         if (r == NULL) goto failed;
 765 
 766         /* parse the request data */
 767         ndr_err = i->table->calls[i->callnum].ndr_pull(m->ndr, NDR_IN, r);
 768         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) goto failed;
 769 
 770         /* make the call */
 771         m->private_data= i->private_data;
 772         m->defer_reply = false;
 773         m->msg_ctx     = msg_ctx;
 774         m->irpc        = i;
 775         m->data        = r;
 776         m->ev          = msg_ctx->event.ev;
 777 
 778         m->header.status = i->fn(m, r);
 779 
 780         if (m->defer_reply) {
 781                 /* the server function has asked to defer the reply to later */
 782                 talloc_steal(msg_ctx, m);
 783                 return;
 784         }
 785 
 786         irpc_send_reply(m, m->header.status);
 787         return;
 788 
 789 failed:
 790         talloc_free(m);
 791 }
 792 
 793 /*
 794   handle an incoming irpc message
 795 */
 796 static void irpc_handler(struct messaging_context *msg_ctx, void *private_data,
     /* [<][>][^][v][top][bottom][index][help] */
 797                          uint32_t msg_type, struct server_id src, DATA_BLOB *packet)
 798 {
 799         struct irpc_message *m;
 800         enum ndr_err_code ndr_err;
 801 
 802         m = talloc(msg_ctx, struct irpc_message);
 803         if (m == NULL) goto failed;
 804 
 805         m->from = src;
 806 
 807         m->ndr = ndr_pull_init_blob(packet, m, msg_ctx->iconv_convenience);
 808         if (m->ndr == NULL) goto failed;
 809 
 810         m->ndr->flags |= LIBNDR_FLAG_REF_ALLOC;
 811 
 812         ndr_err = ndr_pull_irpc_header(m->ndr, NDR_BUFFERS|NDR_SCALARS, &m->header);
 813         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) goto failed;
 814 
 815         if (m->header.flags & IRPC_FLAG_REPLY) {
 816                 irpc_handler_reply(msg_ctx, m);
 817         } else {
 818                 irpc_handler_request(msg_ctx, m);
 819         }
 820         return;
 821 
 822 failed:
 823         talloc_free(m);
 824 }
 825 
 826 
 827 /*
 828   destroy a irpc request
 829 */
 830 static int irpc_destructor(struct irpc_request *irpc)
     /* [<][>][^][v][top][bottom][index][help] */
 831 {
 832         if (irpc->callid != -1) {
 833                 idr_remove(irpc->msg_ctx->idr, irpc->callid);
 834                 irpc->callid = -1;
 835         }
 836 
 837         if (irpc->reject_free) {
 838                 return -1;
 839         }
 840         return 0;
 841 }
 842 
 843 /*
 844   timeout a irpc request
 845 */
 846 static void irpc_timeout(struct tevent_context *ev, struct tevent_timer *te, 
     /* [<][>][^][v][top][bottom][index][help] */
 847                          struct timeval t, void *private_data)
 848 {
 849         struct irpc_request *irpc = talloc_get_type(private_data, struct irpc_request);
 850         irpc->status = NT_STATUS_IO_TIMEOUT;
 851         irpc->done = true;
 852         if (irpc->async.fn) {
 853                 irpc->async.fn(irpc);
 854         }
 855 }
 856 
 857 
 858 /*
 859   make a irpc call - async send
 860 */
 861 struct irpc_request *irpc_call_send(struct messaging_context *msg_ctx, 
     /* [<][>][^][v][top][bottom][index][help] */
 862                                     struct server_id server_id, 
 863                                     const struct ndr_interface_table *table, 
 864                                     int callnum, void *r, TALLOC_CTX *ctx)
 865 {
 866         struct irpc_header header;
 867         struct ndr_push *ndr;
 868         NTSTATUS status;
 869         DATA_BLOB packet;
 870         struct irpc_request *irpc;
 871         enum ndr_err_code ndr_err;
 872 
 873         irpc = talloc(msg_ctx, struct irpc_request);
 874         if (irpc == NULL) goto failed;
 875 
 876         irpc->msg_ctx  = msg_ctx;
 877         irpc->table    = table;
 878         irpc->callnum  = callnum;
 879         irpc->callid   = idr_get_new(msg_ctx->idr, irpc, UINT16_MAX);
 880         if (irpc->callid == -1) goto failed;
 881         irpc->r        = r;
 882         irpc->done     = false;
 883         irpc->async.fn = NULL;
 884         irpc->mem_ctx  = ctx;
 885         irpc->reject_free = false;
 886 
 887         talloc_set_destructor(irpc, irpc_destructor);
 888 
 889         /* setup the header */
 890         header.uuid = table->syntax_id.uuid;
 891 
 892         header.if_version = table->syntax_id.if_version;
 893         header.callid     = irpc->callid;
 894         header.callnum    = callnum;
 895         header.flags      = 0;
 896         header.status     = NT_STATUS_OK;
 897 
 898         /* construct the irpc packet */
 899         ndr = ndr_push_init_ctx(irpc, msg_ctx->iconv_convenience);
 900         if (ndr == NULL) goto failed;
 901 
 902         ndr_err = ndr_push_irpc_header(ndr, NDR_SCALARS|NDR_BUFFERS, &header);
 903         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) goto failed;
 904 
 905         ndr_err = table->calls[callnum].ndr_push(ndr, NDR_IN, r);
 906         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) goto failed;
 907 
 908         /* and send it */
 909         packet = ndr_push_blob(ndr);
 910         status = messaging_send(msg_ctx, server_id, MSG_IRPC, &packet);
 911         if (!NT_STATUS_IS_OK(status)) goto failed;
 912 
 913         event_add_timed(msg_ctx->event.ev, irpc, 
 914                         timeval_current_ofs(IRPC_CALL_TIMEOUT, 0), 
 915                         irpc_timeout, irpc);
 916 
 917         talloc_free(ndr);
 918         return irpc;
 919 
 920 failed:
 921         talloc_free(irpc);
 922         return NULL;
 923 }
 924 
 925 /*
 926   wait for a irpc reply
 927 */
 928 NTSTATUS irpc_call_recv(struct irpc_request *irpc)
     /* [<][>][^][v][top][bottom][index][help] */
 929 {
 930         NTSTATUS status;
 931 
 932         NT_STATUS_HAVE_NO_MEMORY(irpc);
 933 
 934         irpc->reject_free = true;
 935 
 936         while (!irpc->done) {
 937                 if (event_loop_once(irpc->msg_ctx->event.ev) != 0) {
 938                         return NT_STATUS_CONNECTION_DISCONNECTED;
 939                 }
 940         }
 941 
 942         irpc->reject_free = false;
 943 
 944         status = irpc->status;
 945         talloc_free(irpc);
 946         return status;
 947 }
 948 
 949 /*
 950   perform a synchronous irpc request
 951 */
 952 NTSTATUS irpc_call(struct messaging_context *msg_ctx, 
     /* [<][>][^][v][top][bottom][index][help] */
 953                    struct server_id server_id, 
 954                    const struct ndr_interface_table *table, 
 955                    int callnum, void *r,
 956                    TALLOC_CTX *mem_ctx)
 957 {
 958         struct irpc_request *irpc = irpc_call_send(msg_ctx, server_id, 
 959                                                    table, callnum, r, mem_ctx);
 960         return irpc_call_recv(irpc);
 961 }
 962 
 963 /*
 964   open the naming database
 965 */
 966 static struct tdb_wrap *irpc_namedb_open(struct messaging_context *msg_ctx)
     /* [<][>][^][v][top][bottom][index][help] */
 967 {
 968         struct tdb_wrap *t;
 969         char *path = talloc_asprintf(msg_ctx, "%s/names.tdb", msg_ctx->base_path);
 970         if (path == NULL) {
 971                 return NULL;
 972         }
 973         t = tdb_wrap_open(msg_ctx, path, 0, 0, O_RDWR|O_CREAT, 0660);
 974         talloc_free(path);
 975         return t;
 976 }
 977         
 978 
 979 /*
 980   add a string name that this irpc server can be called on
 981 */
 982 NTSTATUS irpc_add_name(struct messaging_context *msg_ctx, const char *name)
     /* [<][>][^][v][top][bottom][index][help] */
 983 {
 984         struct tdb_wrap *t;
 985         TDB_DATA rec;
 986         int count;
 987         NTSTATUS status = NT_STATUS_OK;
 988 
 989         t = irpc_namedb_open(msg_ctx);
 990         NT_STATUS_HAVE_NO_MEMORY(t);
 991 
 992         if (tdb_lock_bystring(t->tdb, name) != 0) {
 993                 talloc_free(t);
 994                 return NT_STATUS_LOCK_NOT_GRANTED;
 995         }
 996         rec = tdb_fetch_bystring(t->tdb, name);
 997         count = rec.dsize / sizeof(struct server_id);
 998         rec.dptr = (unsigned char *)realloc_p(rec.dptr, struct server_id, count+1);
 999         rec.dsize += sizeof(struct server_id);
1000         if (rec.dptr == NULL) {
1001                 tdb_unlock_bystring(t->tdb, name);
1002                 talloc_free(t);
1003                 return NT_STATUS_NO_MEMORY;
1004         }
1005         ((struct server_id *)rec.dptr)[count] = msg_ctx->server_id;
1006         if (tdb_store_bystring(t->tdb, name, rec, 0) != 0) {
1007                 status = NT_STATUS_INTERNAL_ERROR;
1008         }
1009         free(rec.dptr);
1010         tdb_unlock_bystring(t->tdb, name);
1011         talloc_free(t);
1012 
1013         msg_ctx->names = str_list_add(msg_ctx->names, name);
1014         talloc_steal(msg_ctx, msg_ctx->names);
1015 
1016         return status;
1017 }
1018 
1019 /*
1020   return a list of server ids for a server name
1021 */
1022 struct server_id *irpc_servers_byname(struct messaging_context *msg_ctx,
     /* [<][>][^][v][top][bottom][index][help] */
1023                                       TALLOC_CTX *mem_ctx,
1024                                       const char *name)
1025 {
1026         struct tdb_wrap *t;
1027         TDB_DATA rec;
1028         int count, i;
1029         struct server_id *ret;
1030 
1031         t = irpc_namedb_open(msg_ctx);
1032         if (t == NULL) {
1033                 return NULL;
1034         }
1035 
1036         if (tdb_lock_bystring(t->tdb, name) != 0) {
1037                 talloc_free(t);
1038                 return NULL;
1039         }
1040         rec = tdb_fetch_bystring(t->tdb, name);
1041         if (rec.dptr == NULL) {
1042                 tdb_unlock_bystring(t->tdb, name);
1043                 talloc_free(t);
1044                 return NULL;
1045         }
1046         count = rec.dsize / sizeof(struct server_id);
1047         ret = talloc_array(mem_ctx, struct server_id, count+1);
1048         if (ret == NULL) {
1049                 tdb_unlock_bystring(t->tdb, name);
1050                 talloc_free(t);
1051                 return NULL;
1052         }
1053         for (i=0;i<count;i++) {
1054                 ret[i] = ((struct server_id *)rec.dptr)[i];
1055         }
1056         ret[i] = cluster_id(0, 0);
1057         free(rec.dptr);
1058         tdb_unlock_bystring(t->tdb, name);
1059         talloc_free(t);
1060 
1061         return ret;
1062 }
1063 
1064 /*
1065   remove a name from a messaging context
1066 */
1067 void irpc_remove_name(struct messaging_context *msg_ctx, const char *name)
     /* [<][>][^][v][top][bottom][index][help] */
1068 {
1069         struct tdb_wrap *t;
1070         TDB_DATA rec;
1071         int count, i;
1072         struct server_id *ids;
1073 
1074         str_list_remove(msg_ctx->names, name);
1075 
1076         t = irpc_namedb_open(msg_ctx);
1077         if (t == NULL) {
1078                 return;
1079         }
1080 
1081         if (tdb_lock_bystring(t->tdb, name) != 0) {
1082                 talloc_free(t);
1083                 return;
1084         }
1085         rec = tdb_fetch_bystring(t->tdb, name);
1086         if (rec.dptr == NULL) {
1087                 tdb_unlock_bystring(t->tdb, name);
1088                 talloc_free(t);
1089                 return;
1090         }
1091         count = rec.dsize / sizeof(struct server_id);
1092         if (count == 0) {
1093                 free(rec.dptr);
1094                 tdb_unlock_bystring(t->tdb, name);
1095                 talloc_free(t);
1096                 return;
1097         }
1098         ids = (struct server_id *)rec.dptr;
1099         for (i=0;i<count;i++) {
1100                 if (cluster_id_equal(&ids[i], &msg_ctx->server_id)) {
1101                         if (i < count-1) {
1102                                 memmove(ids+i, ids+i+1, 
1103                                         sizeof(struct server_id) * (count-(i+1)));
1104                         }
1105                         rec.dsize -= sizeof(struct server_id);
1106                         break;
1107                 }
1108         }
1109         tdb_store_bystring(t->tdb, name, rec, 0);
1110         free(rec.dptr);
1111         tdb_unlock_bystring(t->tdb, name);
1112         talloc_free(t);
1113 }
1114 
1115 struct server_id messaging_get_server_id(struct messaging_context *msg_ctx)
     /* [<][>][^][v][top][bottom][index][help] */
1116 {
1117         return msg_ctx->server_id;
1118 }

/* [<][>][^][v][top][bottom][index][help] */