source3/rpc_client/rpc_transport_smbd.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *  RPC client transport over named pipes to a child smbd
   4  *  Copyright (C) Volker Lendecke 2009
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "includes.h"
  21
  22 #undef DBGC_CLASS
  23 #define DBGC_CLASS DBGC_RPC_CLI
  24
  25 /**
  26  * struct rpc_cli_smbd_conn represents a forked smbd. This structure should
  27  * exist only once per process which does the rpc calls.
  28  *
  29  * RPC pipe handles can be attached to this smbd connection with
  30  * rpc_pipe_open_local().
  31  *
  32  * For this to work right, we can not use rpc_transport_np directly, because
  33  * the child smbd wants to write its DEBUG output somewhere. We redirect the
  34  * child's output to rpc_cli_smbd_conn->stdout_fd. While the RPC calls are
  35  * active, we have an event context available and attach a fd event to the
  36  * stdout_df.
  37  */
  38
  39 struct rpc_cli_smbd_conn {
  40         /**
  41          * The smb connection to handle the named pipe traffic over
  42          */
  43         struct cli_state *cli;
  44
  45         /**
  46          * Attached to stdout in the forked smbd, this is where smbd will
  47          * print its DEBUG.
  48          */
  49         int stdout_fd;
  50
  51         /**
  52          * Custom callback provided by the owner of the
  53          * rpc_cli_smbd_conn. Here we send the smbd DEBUG output. Can be NULL.
  54          */
  55         struct {
  56                 void (*fn)(char *buf, size_t len, void *priv);
  57                 void *priv;
  58         } stdout_callback ;
  59 };
  60
  61 /**
  62  * Event handler to be called whenever the forked smbd prints debugging
  63  * output.
  64  */
  65
  66 static void rpc_cli_smbd_stdout_reader(struct event_context *ev,
  67                                        struct fd_event *fde,
  68                                        uint16_t flags, void *priv)
  69 {
  70         struct rpc_cli_smbd_conn *conn = talloc_get_type_abort(
  71                 priv, struct rpc_cli_smbd_conn);
  72         char buf[1024];
  73         ssize_t nread;
  74
  75         if ((flags & EVENT_FD_READ) == 0) {
  76                 return;
  77         }
  78
  79         nread = read(conn->stdout_fd, buf, sizeof(buf)-1);
  80         if (nread < 0) {
  81                 DEBUG(0, ("Could not read from smbd stdout: %s\n",
  82                           strerror(errno)));
  83                 TALLOC_FREE(fde);
  84                 return;
  85         }
  86         if (nread == 0) {
  87                 DEBUG(0, ("EOF from smbd stdout\n"));
  88                 TALLOC_FREE(fde);
  89                 return;
  90         }
  91
  92         if (conn->stdout_callback.fn != NULL) {
  93                 conn->stdout_callback.fn(buf, nread,
  94                                          conn->stdout_callback.priv);
  95         }
  96 }
  97
  98 /**
  99  * struct rpc_transport_smbd_state is the link from a struct rpc_pipe_client
 100  * to the rpc_cli_smbd_conn. We use a named pipe transport as a subtransport.
 101  */
 102
 103 struct rpc_transport_smbd_state {
 104         struct rpc_cli_smbd_conn *conn;
 105         struct rpc_cli_transport *sub_transp;
 106 };
 107
 108 static int rpc_cli_smbd_conn_destructor(struct rpc_cli_smbd_conn *conn)
 109 {
 110         if (conn->cli != NULL) {
 111                 cli_shutdown(conn->cli);
 112                 conn->cli = NULL;
 113         }
 114         if (conn->stdout_fd != -1) {
 115                 close(conn->stdout_fd);
 116                 conn->stdout_fd = -1;
 117         }
 118         return 0;
 119 }
 120
 121 /*
 122  * Do the negprot/sesssetup/tcon to an anonymous ipc$ connection
 123  */
 124
 125 struct get_anon_ipc_state {
 126         struct event_context *ev;
 127         struct cli_state *cli;
 128 };
 129
 130 static void get_anon_ipc_negprot_done(struct async_req *subreq);
 131 static void get_anon_ipc_sesssetup_done(struct async_req *subreq);
 132 static void get_anon_ipc_tcon_done(struct async_req *subreq);
 133
 134 static struct async_req *get_anon_ipc_send(TALLOC_CTX *mem_ctx,
 135                                            struct event_context *ev,
 136                                            struct cli_state *cli)
 137 {
 138         struct async_req *result, *subreq;
 139         struct get_anon_ipc_state *state;
 140
 141         if (!async_req_setup(mem_ctx, &result, &state,
 142                              struct get_anon_ipc_state)) {
 143                 return NULL;
 144         }
 145
 146         state->ev = ev;
 147         state->cli = cli;
 148
 149         subreq = cli_negprot_send(state, ev, cli);
 150         if (subreq == NULL) {
 151                 goto fail;
 152         }
 153         subreq->async.fn = get_anon_ipc_negprot_done;
 154         subreq->async.priv = result;
 155         return result;
 156  fail:
 157         TALLOC_FREE(result);
 158         return NULL;
 159 }
 160
 161 static void get_anon_ipc_negprot_done(struct async_req *subreq)
 162 {
 163         struct async_req *req = talloc_get_type_abort(
 164                 subreq->async.priv, struct async_req);
 165         struct get_anon_ipc_state *state = talloc_get_type_abort(
 166                 req->private_data, struct get_anon_ipc_state);
 167         NTSTATUS status;
 168
 169         status = cli_negprot_recv(subreq);
 170         TALLOC_FREE(subreq);
 171         if (!NT_STATUS_IS_OK(status)) {
 172                 async_req_nterror(req, status);
 173                 return;
 174         }
 175
 176         subreq = cli_session_setup_guest_send(state, state->ev, state->cli);
 177         if (async_req_nomem(subreq, req)) {
 178                 return;
 179         }
 180         subreq->async.fn = get_anon_ipc_sesssetup_done;
 181         subreq->async.priv = req;
 182 }
 183
 184 static void get_anon_ipc_sesssetup_done(struct async_req *subreq)
 185 {
 186         struct async_req *req = talloc_get_type_abort(
 187                 subreq->async.priv, struct async_req);
 188         struct get_anon_ipc_state *state = talloc_get_type_abort(
 189                 req->private_data, struct get_anon_ipc_state);
 190         NTSTATUS status;
 191
 192         status = cli_session_setup_guest_recv(subreq);
 193         TALLOC_FREE(subreq);
 194         if (!NT_STATUS_IS_OK(status)) {
 195                 async_req_nterror(req, status);
 196                 return;
 197         }
 198
 199         subreq = cli_tcon_andx_send(state, state->ev, state->cli,
 200                                     "IPC$", "IPC", NULL, 0);
 201         if (async_req_nomem(subreq, req)) {
 202                 return;
 203         }
 204         subreq->async.fn = get_anon_ipc_tcon_done;
 205         subreq->async.priv = req;
 206 }
 207
 208 static void get_anon_ipc_tcon_done(struct async_req *subreq)
 209 {
 210         struct async_req *req = talloc_get_type_abort(
 211                 subreq->async.priv, struct async_req);
 212         NTSTATUS status;
 213
 214         status = cli_tcon_andx_recv(subreq);
 215         TALLOC_FREE(subreq);
 216         if (!NT_STATUS_IS_OK(status)) {
 217                 async_req_nterror(req, status);
 218                 return;
 219         }
 220         async_req_done(req);
 221 }
 222
 223 static NTSTATUS get_anon_ipc_recv(struct async_req *req)
 224 {
 225         return async_req_simple_recv_ntstatus(req);
 226 }
 227
 228 struct rpc_cli_smbd_conn_init_state {
 229         struct event_context *ev;
 230         struct rpc_cli_smbd_conn *conn;
 231 };
 232
 233 static void rpc_cli_smbd_conn_init_done(struct async_req *subreq);
 234
 235 struct async_req *rpc_cli_smbd_conn_init_send(TALLOC_CTX *mem_ctx,
 236                                               struct event_context *ev,
 237                                               void (*stdout_callback)(char *buf,
 238                                                                       size_t len,
 239                                                                       void *priv),
 240                                               void *priv)
 241 {
 242         struct async_req *result, *subreq;
 243         struct rpc_cli_smbd_conn_init_state *state;
 244         int smb_sock[2];
 245         int stdout_pipe[2];
 246         NTSTATUS status;
 247         pid_t pid;
 248         int ret;
 249
 250         smb_sock[0] = smb_sock[1] = stdout_pipe[0] = stdout_pipe[1] = -1;
 251
 252         if (!async_req_setup(mem_ctx, &result, &state,
 253                              struct rpc_cli_smbd_conn_init_state)) {
 254                 return NULL;
 255         }
 256         state->ev = ev;
 257
 258         state->conn = talloc(state, struct rpc_cli_smbd_conn);
 259         if (state->conn == NULL) {
 260                 goto nomem;
 261         }
 262
 263         state->conn->cli = cli_initialise();
 264         if (state->conn->cli == NULL) {
 265                 goto nomem;
 266         }
 267         state->conn->stdout_fd = -1;
 268         state->conn->stdout_callback.fn = stdout_callback;
 269         state->conn->stdout_callback.priv = priv;
 270         talloc_set_destructor(state->conn, rpc_cli_smbd_conn_destructor);
 271
 272         ret = socketpair(AF_UNIX, SOCK_STREAM, 0, smb_sock);
 273         if (ret == -1) {
 274                 status = map_nt_error_from_unix(errno);
 275                 goto post_status;
 276         }
 277         ret = pipe(stdout_pipe);
 278         if (ret == -1) {
 279                 status = map_nt_error_from_unix(errno);
 280                 goto post_status;
 281         }
 282
 283         pid = sys_fork();
 284         if (pid == -1) {
 285                 status = map_nt_error_from_unix(errno);
 286                 goto post_status;
 287         }
 288         if (pid == 0) {
 289                 char *smbd_cmd;
 290
 291                 close(smb_sock[0]);
 292                 close(stdout_pipe[0]);
 293                 close(0);
 294                 if (dup(smb_sock[1]) == -1) {
 295                         exit(1);
 296                 }
 297                 close(smb_sock[1]);
 298                 close(1);
 299                 if (dup(stdout_pipe[1]) == -1) {
 300                         exit(1);
 301                 }
 302                 close(stdout_pipe[1]);
 303
 304                 smbd_cmd = getenv("SMB_PATH");
 305
 306                 if ((smbd_cmd == NULL)
 307                     && (asprintf(&smbd_cmd, "%s/smbd", get_dyn_SBINDIR())
 308                         == -1)) {
 309                         printf("no memory");
 310                         exit(1);
 311                 }
 312                 if (asprintf(&smbd_cmd, "%s -F -S", smbd_cmd) == -1) {
 313                         printf("no memory");
 314                         exit(1);
 315                 }
 316
 317                 exit(system(smbd_cmd));
 318         }
 319
 320         state->conn->cli->fd = smb_sock[0];
 321         smb_sock[0] = -1;
 322         close(smb_sock[1]);
 323         smb_sock[1] = -1;
 324
 325         state->conn->stdout_fd = stdout_pipe[0];
 326         stdout_pipe[0] = -1;
 327         close(stdout_pipe[1]);
 328         stdout_pipe[1] = -1;
 329
 330         subreq = get_anon_ipc_send(state, ev, state->conn->cli);
 331         if (subreq == NULL) {
 332                 goto nomem;
 333         }
 334
 335         if (event_add_fd(ev, subreq, state->conn->stdout_fd, EVENT_FD_READ,
 336                          rpc_cli_smbd_stdout_reader, state->conn) == NULL) {
 337                 goto nomem;
 338         }
 339
 340         subreq->async.fn = rpc_cli_smbd_conn_init_done;
 341         subreq->async.priv = result;
 342         return result;
 343
 344  nomem:
 345         status = NT_STATUS_NO_MEMORY;
 346  post_status:
 347         if (smb_sock[0] != -1) {
 348                 close(smb_sock[0]);
 349         }
 350         if (smb_sock[1] != -1) {
 351                 close(smb_sock[1]);
 352         }
 353         if (stdout_pipe[0] != -1) {
 354                 close(stdout_pipe[0]);
 355         }
 356         if (stdout_pipe[1] != -1) {
 357                 close(stdout_pipe[1]);
 358         }
 359         if (async_post_ntstatus(result, ev, status)) {
 360                 return result;
 361         }
 362         TALLOC_FREE(result);
 363         return NULL;
 364 }
 365
 366 static void rpc_cli_smbd_conn_init_done(struct async_req *subreq)
 367 {
 368         struct async_req *req = talloc_get_type_abort(
 369                 subreq->async.priv, struct async_req);
 370         NTSTATUS status;
 371
 372         status = get_anon_ipc_recv(subreq);
 373         TALLOC_FREE(subreq);
 374         if (!NT_STATUS_IS_OK(status)) {
 375                 async_req_nterror(req, status);
 376                 return;
 377         }
 378         async_req_done(req);
 379 }
 380
 381 NTSTATUS rpc_cli_smbd_conn_init_recv(struct async_req *req,
 382                                      TALLOC_CTX *mem_ctx,
 383                                      struct rpc_cli_smbd_conn **pconn)
 384 {
 385         struct rpc_cli_smbd_conn_init_state *state = talloc_get_type_abort(
 386                 req->private_data, struct rpc_cli_smbd_conn_init_state);
 387         NTSTATUS status;
 388
 389         if (async_req_is_nterror(req, &status)) {
 390                 return status;
 391         }
 392         *pconn = talloc_move(mem_ctx, &state->conn);
 393         return NT_STATUS_OK;
 394 }
 395
 396 NTSTATUS rpc_cli_smbd_conn_init(TALLOC_CTX *mem_ctx,
 397                                 struct rpc_cli_smbd_conn **pconn,
 398                                 void (*stdout_callback)(char *buf,
 399                                                         size_t len,
 400                                                         void *priv),
 401                                 void *priv)
 402 {
 403         TALLOC_CTX *frame = talloc_stackframe();
 404         struct event_context *ev;
 405         struct async_req *req;
 406         NTSTATUS status;
 407
 408         ev = event_context_init(frame);
 409         if (ev == NULL) {
 410                 status = NT_STATUS_NO_MEMORY;
 411                 goto fail;
 412         }
 413
 414         req = rpc_cli_smbd_conn_init_send(frame, ev, stdout_callback, priv);
 415         if (req == NULL) {
 416                 status = NT_STATUS_NO_MEMORY;
 417                 goto fail;
 418         }
 419
 420         while (req->state < ASYNC_REQ_DONE) {
 421                 event_loop_once(ev);
 422         }
 423
 424         status = rpc_cli_smbd_conn_init_recv(req, mem_ctx, pconn);
 425  fail:
 426         TALLOC_FREE(frame);
 427         return status;
 428 }
 429
 430 struct rpc_smbd_write_state {
 431         struct rpc_cli_transport *sub_transp;
 432         ssize_t written;
 433 };
 434
 435 static void rpc_smbd_write_done(struct async_req *subreq);
 436
 437 static struct async_req *rpc_smbd_write_send(TALLOC_CTX *mem_ctx,
 438                                              struct event_context *ev,
 439                                              const uint8_t *data, size_t size,
 440                                              void *priv)
 441 {
 442         struct rpc_transport_smbd_state *transp = talloc_get_type_abort(
 443                 priv, struct rpc_transport_smbd_state);
 444         struct async_req *result, *subreq;
 445         struct rpc_smbd_write_state *state;
 446
 447         if (!async_req_setup(mem_ctx, &result, &state,
 448                              struct rpc_smbd_write_state)) {
 449                 return NULL;
 450         }
 451         state->sub_transp = transp->sub_transp;
 452
 453         subreq = transp->sub_transp->write_send(state, ev, data, size,
 454                                                 transp->sub_transp->priv);
 455         if (subreq == NULL) {
 456                 goto fail;
 457         }
 458
 459         if (event_add_fd(ev, subreq, transp->conn->stdout_fd, EVENT_FD_READ,
 460                          rpc_cli_smbd_stdout_reader, transp->conn) == NULL) {
 461                 goto fail;
 462         }
 463
 464         subreq->async.fn = rpc_smbd_write_done;
 465         subreq->async.priv = result;
 466         return result;
 467
 468  fail:
 469         TALLOC_FREE(result);
 470         return NULL;
 471 }
 472
 473 static void rpc_smbd_write_done(struct async_req *subreq)
 474 {
 475         struct async_req *req = talloc_get_type_abort(
 476                 subreq->async.priv, struct async_req);
 477         struct rpc_smbd_write_state *state = talloc_get_type_abort(
 478                 req->private_data, struct rpc_smbd_write_state);
 479         NTSTATUS status;
 480
 481         status = state->sub_transp->write_recv(subreq, &state->written);
 482         TALLOC_FREE(subreq);
 483         if (!NT_STATUS_IS_OK(status)) {
 484                 async_req_nterror(req, status);
 485                 return;
 486         }
 487         async_req_done(req);
 488 }
 489
 490 static NTSTATUS rpc_smbd_write_recv(struct async_req *req, ssize_t *pwritten)
 491 {
 492         struct rpc_smbd_write_state *state = talloc_get_type_abort(
 493                 req->private_data, struct rpc_smbd_write_state);
 494         NTSTATUS status;
 495
 496         if (async_req_is_nterror(req, &status)) {
 497                 return status;
 498         }
 499         *pwritten = state->written;
 500         return NT_STATUS_OK;
 501 }
 502
 503 struct rpc_smbd_read_state {
 504         struct rpc_cli_transport *sub_transp;
 505         ssize_t received;
 506 };
 507
 508 static void rpc_smbd_read_done(struct async_req *subreq);
 509
 510 static struct async_req *rpc_smbd_read_send(TALLOC_CTX *mem_ctx,
 511                                             struct event_context *ev,
 512                                             uint8_t *data, size_t size,
 513                                             void *priv)
 514 {
 515         struct rpc_transport_smbd_state *transp = talloc_get_type_abort(
 516                 priv, struct rpc_transport_smbd_state);
 517         struct async_req *result, *subreq;
 518         struct rpc_smbd_read_state *state;
 519
 520         if (!async_req_setup(mem_ctx, &result, &state,
 521                              struct rpc_smbd_read_state)) {
 522                 return NULL;
 523         }
 524         state->sub_transp = transp->sub_transp;
 525
 526         subreq = transp->sub_transp->read_send(state, ev, data, size,
 527                                                 transp->sub_transp->priv);
 528         if (subreq == NULL) {
 529                 goto fail;
 530         }
 531
 532         if (event_add_fd(ev, subreq, transp->conn->stdout_fd, EVENT_FD_READ,
 533                          rpc_cli_smbd_stdout_reader, transp->conn) == NULL) {
 534                 goto fail;
 535         }
 536
 537         subreq->async.fn = rpc_smbd_read_done;
 538         subreq->async.priv = result;
 539         return result;
 540
 541  fail:
 542         TALLOC_FREE(result);
 543         return NULL;
 544 }
 545
 546 static void rpc_smbd_read_done(struct async_req *subreq)
 547 {
 548         struct async_req *req = talloc_get_type_abort(
 549                 subreq->async.priv, struct async_req);
 550         struct rpc_smbd_read_state *state = talloc_get_type_abort(
 551                 req->private_data, struct rpc_smbd_read_state);
 552         NTSTATUS status;
 553
 554         status = state->sub_transp->read_recv(subreq, &state->received);
 555         TALLOC_FREE(subreq);
 556         if (!NT_STATUS_IS_OK(status)) {
 557                 async_req_nterror(req, status);
 558                 return;
 559         }
 560         async_req_done(req);
 561 }
 562
 563 static NTSTATUS rpc_smbd_read_recv(struct async_req *req, ssize_t *preceived)
 564 {
 565         struct rpc_smbd_read_state *state = talloc_get_type_abort(
 566                 req->private_data, struct rpc_smbd_read_state);
 567         NTSTATUS status;
 568
 569         if (async_req_is_nterror(req, &status)) {
 570                 return status;
 571         }
 572         *preceived = state->received;
 573         return NT_STATUS_OK;
 574 }
 575
 576 struct rpc_transport_smbd_init_state {
 577         struct rpc_cli_transport *transport;
 578         struct rpc_transport_smbd_state *transport_smbd;
 579 };
 580
 581 static void rpc_transport_smbd_init_done(struct async_req *subreq);
 582
 583 struct async_req *rpc_transport_smbd_init_send(TALLOC_CTX *mem_ctx,
 584                                                struct event_context *ev,
 585                                                struct rpc_cli_smbd_conn *conn,
 586                                                const struct ndr_syntax_id *abstract_syntax)
 587 {
 588         struct async_req *result, *subreq;
 589         struct rpc_transport_smbd_init_state *state;
 590
 591         if (!async_req_setup(mem_ctx, &result, &state,
 592                              struct rpc_transport_smbd_init_state)) {
 593                 return NULL;
 594         }
 595
 596         state->transport = talloc(state, struct rpc_cli_transport);
 597         if (state->transport == NULL) {
 598                 goto fail;
 599         }
 600         state->transport_smbd = talloc(state->transport,
 601                                        struct rpc_transport_smbd_state);
 602         if (state->transport_smbd == NULL) {
 603                 goto fail;
 604         }
 605         state->transport_smbd->conn = conn;
 606         state->transport->priv = state->transport_smbd;
 607
 608         subreq = rpc_transport_np_init_send(state, ev, conn->cli,
 609                                             abstract_syntax);
 610         if (subreq == NULL) {
 611                 goto fail;
 612         }
 613         subreq->async.fn = rpc_transport_smbd_init_done;
 614         subreq->async.priv = result;
 615         return result;
 616
 617  fail:
 618         TALLOC_FREE(result);
 619         return NULL;
 620 }
 621
 622 static void rpc_transport_smbd_init_done(struct async_req *subreq)
 623 {
 624         struct async_req *req = talloc_get_type_abort(
 625                 subreq->async.priv, struct async_req);
 626         struct rpc_transport_smbd_init_state *state = talloc_get_type_abort(
 627                 req->private_data, struct rpc_transport_smbd_init_state);
 628         NTSTATUS status;
 629
 630         status = rpc_transport_np_init_recv(
 631                 subreq, state->transport_smbd,
 632                 &state->transport_smbd->sub_transp);
 633         TALLOC_FREE(subreq);
 634         if (!NT_STATUS_IS_OK(status)) {
 635                 async_req_nterror(req, status);
 636                 return;
 637         }
 638         async_req_done(req);
 639 }
 640
 641 NTSTATUS rpc_transport_smbd_init_recv(struct async_req *req,
 642                                       TALLOC_CTX *mem_ctx,
 643                                       struct rpc_cli_transport **presult)
 644 {
 645         struct rpc_transport_smbd_init_state *state = talloc_get_type_abort(
 646                 req->private_data, struct rpc_transport_smbd_init_state);
 647         NTSTATUS status;
 648
 649         if (async_req_is_nterror(req, &status)) {
 650                 return status;
 651         }
 652
 653         state->transport->write_send = rpc_smbd_write_send;
 654         state->transport->write_recv = rpc_smbd_write_recv;
 655         state->transport->read_send = rpc_smbd_read_send;
 656         state->transport->read_recv = rpc_smbd_read_recv;
 657         state->transport->trans_send = NULL;
 658         state->transport->trans_recv = NULL;
 659
 660         *presult = talloc_move(mem_ctx, &state->transport);
 661         return NT_STATUS_OK;
 662 }
 663
 664 NTSTATUS rpc_transport_smbd_init(TALLOC_CTX *mem_ctx,
 665                                  struct rpc_cli_smbd_conn *conn,
 666                                  const struct ndr_syntax_id *abstract_syntax,
 667                                  struct rpc_cli_transport **presult)
 668 {
 669         TALLOC_CTX *frame = talloc_stackframe();
 670         struct event_context *ev;
 671         struct async_req *req;
 672         NTSTATUS status;
 673
 674         ev = event_context_init(frame);
 675         if (ev == NULL) {
 676                 status = NT_STATUS_NO_MEMORY;
 677                 goto fail;
 678         }
 679
 680         req = rpc_transport_smbd_init_send(frame, ev, conn, abstract_syntax);
 681         if (req == NULL) {
 682                 status = NT_STATUS_NO_MEMORY;
 683                 goto fail;
 684         }
 685
 686         while (req->state < ASYNC_REQ_DONE) {
 687                 event_loop_once(ev);
 688         }
 689
 690         status = rpc_transport_smbd_init_recv(req, mem_ctx, presult);
 691  fail:
 692         TALLOC_FREE(frame);
 693         return status;
 694 }