source/libsmb/clireadwrite.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    client file read/write routines
   4    Copyright (C) Andrew Tridgell 1994-1998
   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 /****************************************************************************
  23   Calculate the recommended read buffer size
  24 ****************************************************************************/
  25 static size_t cli_read_max_bufsize(struct cli_state *cli)
  26 {
  27         if (!client_is_signing_on(cli) && !cli_encryption_on(cli)
  28             && (cli->posix_capabilities & CIFS_UNIX_LARGE_READ_CAP)) {
  29                 return CLI_SAMBA_MAX_POSIX_LARGE_READX_SIZE;
  30         }
  31         if (cli->capabilities & CAP_LARGE_READX) {
  32                 return cli->is_samba
  33                         ? CLI_SAMBA_MAX_LARGE_READX_SIZE
  34                         : CLI_WINDOWS_MAX_LARGE_READX_SIZE;
  35         }
  36         return (cli->max_xmit - (smb_size+32)) & ~1023;
  37 }
  38
  39 /*
  40  * Send a read&x request
  41  */
  42
  43 struct async_req *cli_read_andx_send(TALLOC_CTX *mem_ctx,
  44                                      struct cli_state *cli, int fnum,
  45                                      off_t offset, size_t size)
  46 {
  47         struct async_req *result;
  48         struct cli_request *req;
  49         bool bigoffset = False;
  50         char *enc_buf;
  51
  52         if (size > cli_read_max_bufsize(cli)) {
  53                 DEBUG(0, ("cli_read_andx_send got size=%d, can only handle "
  54                           "size=%d\n", (int)size,
  55                           (int)cli_read_max_bufsize(cli)));
  56                 return NULL;
  57         }
  58
  59         result = cli_request_new(mem_ctx, cli->event_ctx, cli, 12, 0, &req);
  60         if (result == NULL) {
  61                 DEBUG(0, ("cli_request_new failed\n"));
  62                 return NULL;
  63         }
  64
  65         req->data.read.ofs = offset;
  66         req->data.read.size = size;
  67         req->data.read.received = 0;
  68         req->data.read.rcvbuf = NULL;
  69
  70         if ((SMB_BIG_UINT)offset >> 32)
  71                 bigoffset = True;
  72
  73         cli_set_message(req->outbuf, bigoffset ? 12 : 10, 0, False);
  74
  75         SCVAL(req->outbuf,smb_com,SMBreadX);
  76         SSVAL(req->outbuf,smb_tid,cli->cnum);
  77         cli_setup_packet_buf(cli, req->outbuf);
  78
  79         SCVAL(req->outbuf,smb_vwv0,0xFF);
  80         SCVAL(req->outbuf,smb_vwv0+1,0);
  81         SSVAL(req->outbuf,smb_vwv1,0);
  82         SSVAL(req->outbuf,smb_vwv2,fnum);
  83         SIVAL(req->outbuf,smb_vwv3,offset);
  84         SSVAL(req->outbuf,smb_vwv5,size);
  85         SSVAL(req->outbuf,smb_vwv6,size);
  86         SSVAL(req->outbuf,smb_vwv7,(size >> 16));
  87         SSVAL(req->outbuf,smb_vwv8,0);
  88         SSVAL(req->outbuf,smb_vwv9,0);
  89         SSVAL(req->outbuf,smb_mid,req->mid);
  90
  91         if (bigoffset) {
  92                 SIVAL(req->outbuf, smb_vwv10,
  93                       (((SMB_BIG_UINT)offset)>>32) & 0xffffffff);
  94         }
  95
  96         cli_calculate_sign_mac(cli, req->outbuf);
  97
  98         event_fd_set_writeable(cli->fd_event);
  99
 100         if (cli_encryption_on(cli)) {
 101                 NTSTATUS status;
 102                 status = cli_encrypt_message(cli, req->outbuf, &enc_buf);
 103                 if (!NT_STATUS_IS_OK(status)) {
 104                         DEBUG(0, ("Error in encrypting client message. "
 105                                   "Error %s\n", nt_errstr(status)));
 106                         TALLOC_FREE(req);
 107                         return NULL;
 108                 }
 109                 req->outbuf = enc_buf;
 110                 req->enc_state = cli->trans_enc_state;
 111         }
 112
 113         return result;
 114 }
 115
 116 /*
 117  * Pull the data out of a finished async read_and_x request. rcvbuf is
 118  * talloced from the request, so better make sure that you copy it away before
 119  * you talloc_free(req). "rcvbuf" is NOT a talloc_ctx of its own, so do not
 120  * talloc_move it!
 121  */
 122
 123 NTSTATUS cli_read_andx_recv(struct async_req *req, ssize_t *received,
 124                             uint8_t **rcvbuf)
 125 {
 126         struct cli_request *cli_req = cli_request_get(req);
 127         NTSTATUS status;
 128         size_t size;
 129
 130         SMB_ASSERT(req->state >= ASYNC_REQ_DONE);
 131         if (req->state == ASYNC_REQ_ERROR) {
 132                 return req->status;
 133         }
 134
 135         status = cli_pull_error(cli_req->inbuf);
 136
 137         if (NT_STATUS_IS_ERR(status)) {
 138                 return status;
 139         }
 140
 141         /* size is the number of bytes the server returned.
 142          * Might be zero. */
 143         size = SVAL(cli_req->inbuf, smb_vwv5);
 144         size |= (((unsigned int)(SVAL(cli_req->inbuf, smb_vwv7))) << 16);
 145
 146         if (size > cli_req->data.read.size) {
 147                 DEBUG(5,("server returned more than we wanted!\n"));
 148                 return NT_STATUS_UNEXPECTED_IO_ERROR;
 149         }
 150
 151         *rcvbuf = (uint8_t *)
 152                 (smb_base(cli_req->inbuf) + SVAL(cli_req->inbuf, smb_vwv6));
 153         *received = size;
 154         return NT_STATUS_OK;
 155 }
 156
 157 struct cli_readall_state {
 158         struct cli_state *cli;
 159         uint16_t fnum;
 160         off_t start_offset;
 161         size_t size;
 162         size_t received;
 163         uint8_t *buf;
 164 };
 165
 166 static void cli_readall_done(struct async_req *subreq);
 167
 168 static struct async_req *cli_readall_send(TALLOC_CTX *mem_ctx,
 169                                           struct cli_state *cli,
 170                                           uint16_t fnum,
 171                                           off_t offset, size_t size)
 172 {
 173         struct async_req *req, *subreq;
 174         struct cli_readall_state *state;
 175
 176         req = async_req_new(mem_ctx, cli->event_ctx);
 177         if (req == NULL) {
 178                 return NULL;
 179         }
 180         state = talloc(req, struct cli_readall_state);
 181         if (state == NULL) {
 182                 TALLOC_FREE(req);
 183                 return NULL;
 184         }
 185         req->private_data = state;
 186
 187         state->cli = cli;
 188         state->fnum = fnum;
 189         state->start_offset = offset;
 190         state->size = size;
 191         state->received = 0;
 192         state->buf = NULL;
 193
 194         subreq = cli_read_andx_send(state, cli, fnum, offset, size);
 195         if (subreq == NULL) {
 196                 TALLOC_FREE(req);
 197                 return NULL;
 198         }
 199         subreq->async.fn = cli_readall_done;
 200         subreq->async.priv = req;
 201         return req;
 202 }
 203
 204 static void cli_readall_done(struct async_req *subreq)
 205 {
 206         struct async_req *req = talloc_get_type_abort(
 207                 subreq->async.priv, struct async_req);
 208         struct cli_readall_state *state = talloc_get_type_abort(
 209                 req->private_data, struct cli_readall_state);
 210         ssize_t received;
 211         uint8_t *buf;
 212         NTSTATUS status;
 213
 214         status = cli_read_andx_recv(subreq, &received, &buf);
 215         if (!NT_STATUS_IS_OK(status)) {
 216                 async_req_error(req, status);
 217                 return;
 218         }
 219
 220         if (received == 0) {
 221                 /* EOF */
 222                 async_req_done(req);
 223                 return;
 224         }
 225
 226         if ((state->received == 0) && (received == state->size)) {
 227                 /* Ideal case: Got it all in one run */
 228                 state->buf = buf;
 229                 state->received += received;
 230                 async_req_done(req);
 231                 return;
 232         }
 233
 234         /*
 235          * We got a short read, issue a read for the
 236          * rest. Unfortunately we have to allocate the buffer
 237          * ourselves now, as our caller expects to receive a single
 238          * buffer. cli_read_andx does it from the buffer received from
 239          * the net, but with a short read we have to put it together
 240          * from several reads.
 241          */
 242
 243         if (state->buf == NULL) {
 244                 state->buf = talloc_array(state, uint8_t, state->size);
 245                 if (async_req_nomem(state->buf, req)) {
 246                         return;
 247                 }
 248         }
 249         memcpy(state->buf + state->received, buf, received);
 250         state->received += received;
 251
 252         TALLOC_FREE(subreq);
 253
 254         if (state->received >= state->size) {
 255                 async_req_done(req);
 256                 return;
 257         }
 258
 259         subreq = cli_read_andx_send(state, state->cli, state->fnum,
 260                                     state->start_offset + state->received,
 261                                     state->size - state->received);
 262         if (async_req_nomem(subreq, req)) {
 263                 return;
 264         }
 265         subreq->async.fn = cli_readall_done;
 266         subreq->async.priv = req;
 267 }
 268
 269 static NTSTATUS cli_readall_recv(struct async_req *req, ssize_t *received,
 270                                  uint8_t **rcvbuf)
 271 {
 272         struct cli_readall_state *state = talloc_get_type_abort(
 273                 req->private_data, struct cli_readall_state);
 274
 275         SMB_ASSERT(req->state >= ASYNC_REQ_DONE);
 276         if (req->state == ASYNC_REQ_ERROR) {
 277                 return req->status;
 278         }
 279         *received = state->received;
 280         *rcvbuf = state->buf;
 281         return NT_STATUS_OK;
 282 }
 283
 284 /*
 285  * Parallel read support.
 286  *
 287  * cli_pull sends as many read&x requests as the server would allow via
 288  * max_mux at a time. When replies flow back in, the data is written into
 289  * the callback function "sink" in the right order.
 290  */
 291
 292 struct cli_pull_subreq {
 293         struct async_req *req;
 294         size_t received;
 295         uint8_t *buf;
 296 };
 297
 298 struct cli_pull_state {
 299         struct async_req *req;
 300
 301         struct cli_state *cli;
 302         uint16_t fnum;
 303         off_t start_offset;
 304         SMB_OFF_T size;
 305
 306         NTSTATUS (*sink)(char *buf, size_t n, void *priv);
 307         void *priv;
 308
 309         size_t chunk_size;
 310
 311         /*
 312          * Outstanding requests
 313          */
 314         int num_reqs;
 315         struct cli_pull_subreq *reqs;
 316
 317         /*
 318          * For how many bytes did we send requests already?
 319          */
 320         SMB_OFF_T requested;
 321
 322         /*
 323          * Next request index to push into "sink". This walks around the "req"
 324          * array, taking care that the requests are pushed to "sink" in the
 325          * right order. If necessary (i.e. replies don't come in in the right
 326          * order), replies are held back in "reqs".
 327          */
 328         int top_req;
 329
 330         /*
 331          * How many bytes did we push into "sink"?
 332          */
 333
 334         SMB_OFF_T pushed;
 335 };
 336
 337 static char *cli_pull_print(TALLOC_CTX *mem_ctx, struct async_req *req)
 338 {
 339         struct cli_pull_state *state = talloc_get_type_abort(
 340                 req->private_data, struct cli_pull_state);
 341         char *result;
 342
 343         result = async_req_print(mem_ctx, req);
 344         if (result == NULL) {
 345                 return NULL;
 346         }
 347
 348         return talloc_asprintf_append_buffer(
 349                 result, "num_reqs=%d, top_req=%d",
 350                 state->num_reqs, state->top_req);
 351 }
 352
 353 static void cli_pull_read_done(struct async_req *read_req);
 354
 355 /*
 356  * Prepare an async pull request
 357  */
 358
 359 struct async_req *cli_pull_send(TALLOC_CTX *mem_ctx, struct cli_state *cli,
 360                                 uint16_t fnum, off_t start_offset,
 361                                 SMB_OFF_T size, size_t window_size,
 362                                 NTSTATUS (*sink)(char *buf, size_t n,
 363                                                  void *priv),
 364                                 void *priv)
 365 {
 366         struct async_req *result;
 367         struct cli_pull_state *state;
 368         int i;
 369
 370         result = async_req_new(mem_ctx, cli->event_ctx);
 371         if (result == NULL) {
 372                 goto failed;
 373         }
 374         state = talloc(result, struct cli_pull_state);
 375         if (state == NULL) {
 376                 goto failed;
 377         }
 378         result->private_data = state;
 379         result->print = cli_pull_print;
 380         state->req = result;
 381
 382         state->cli = cli;
 383         state->fnum = fnum;
 384         state->start_offset = start_offset;
 385         state->size = size;
 386         state->sink = sink;
 387         state->priv = priv;
 388
 389         state->pushed = 0;
 390         state->top_req = 0;
 391
 392         if (size == 0) {
 393                 if (!async_post_status(result, NT_STATUS_OK)) {
 394                         goto failed;
 395                 }
 396                 return result;
 397         }
 398
 399         state->chunk_size = cli_read_max_bufsize(cli);
 400
 401         state->num_reqs = MAX(window_size/state->chunk_size, 1);
 402         state->num_reqs = MIN(state->num_reqs, cli->max_mux);
 403
 404         state->reqs = TALLOC_ZERO_ARRAY(state, struct cli_pull_subreq,
 405                                         state->num_reqs);
 406         if (state->reqs == NULL) {
 407                 goto failed;
 408         }
 409
 410         state->requested = 0;
 411
 412         for (i=0; i<state->num_reqs; i++) {
 413                 SMB_OFF_T size_left;
 414                 size_t request_thistime;
 415
 416                 if (state->requested >= size) {
 417                         state->num_reqs = i;
 418                         break;
 419                 }
 420
 421                 size_left = size - state->requested;
 422                 request_thistime = MIN(size_left, state->chunk_size);
 423
 424                 state->reqs[i].req = cli_readall_send(
 425                         state->reqs, cli, fnum,
 426                         state->start_offset + state->requested,
 427                         request_thistime);
 428
 429                 if (state->reqs[i].req == NULL) {
 430                         goto failed;
 431                 }
 432
 433                 state->reqs[i].req->async.fn = cli_pull_read_done;
 434                 state->reqs[i].req->async.priv = result;
 435
 436                 state->requested += request_thistime;
 437         }
 438         return result;
 439
 440 failed:
 441         TALLOC_FREE(result);
 442         return NULL;
 443 }
 444
 445 /*
 446  * Handle incoming read replies, push the data into sink and send out new
 447  * requests if necessary.
 448  */
 449
 450 static void cli_pull_read_done(struct async_req *read_req)
 451 {
 452         struct async_req *pull_req = talloc_get_type_abort(
 453                 read_req->async.priv, struct async_req);
 454         struct cli_pull_state *state = talloc_get_type_abort(
 455                 pull_req->private_data, struct cli_pull_state);
 456         ssize_t received;
 457         uint8_t *buf;
 458         NTSTATUS status;
 459         int i;
 460
 461         status = cli_readall_recv(read_req, &received, &buf);
 462         if (!NT_STATUS_IS_OK(status)) {
 463                 async_req_error(state->req, status);
 464                 return;
 465         }
 466
 467         for (i=0; i<state->num_reqs; i++) {
 468                 if (state->reqs[i].req == read_req) {
 469                         break;
 470                 }
 471         }
 472
 473         if (i == state->num_reqs) {
 474                 /* Got something we did not send. Just drop it. */
 475                 TALLOC_FREE(read_req);
 476                 return;
 477         }
 478
 479         state->reqs[i].received = received;
 480         state->reqs[i].buf = buf;
 481
 482         /*
 483          * This loop is the one to take care of out-of-order replies. All
 484          * pending requests are in state->reqs, state->reqs[top_req] is the
 485          * one that is to be pushed next. If however a request later than
 486          * top_req is replied to, then we can't push yet. If top_req is
 487          * replied to at a later point then, we need to push all the finished
 488          * requests.
 489          */
 490
 491         while (state->reqs[state->top_req].req != NULL) {
 492                 struct cli_pull_subreq *top_read;
 493
 494                 DEBUG(11, ("cli_pull_read_done: top_req = %d\n",
 495                            state->top_req));
 496
 497                 if (state->reqs[state->top_req].req->state < ASYNC_REQ_DONE) {
 498                         DEBUG(11, ("cli_pull_read_done: top request not yet "
 499                                    "done\n"));
 500                         return;
 501                 }
 502
 503                 top_read = &state->reqs[state->top_req];
 504
 505                 DEBUG(10, ("cli_pull_read_done: Pushing %d bytes, %d already "
 506                            "pushed\n", (int)top_read->received,
 507                            (int)state->pushed));
 508
 509                 status = state->sink((char *)top_read->buf, top_read->received,
 510                                      state->priv);
 511                 if (!NT_STATUS_IS_OK(status)) {
 512                         async_req_error(state->req, status);
 513                         return;
 514                 }
 515                 state->pushed += top_read->received;
 516
 517                 TALLOC_FREE(state->reqs[state->top_req].req);
 518
 519                 if (state->requested < state->size) {
 520                         struct async_req *new_req;
 521                         SMB_OFF_T size_left;
 522                         size_t request_thistime;
 523
 524                         size_left = state->size - state->requested;
 525                         request_thistime = MIN(size_left, state->chunk_size);
 526
 527                         DEBUG(10, ("cli_pull_read_done: Requesting %d bytes "
 528                                    "at %d, position %d\n",
 529                                    (int)request_thistime,
 530                                    (int)(state->start_offset
 531                                          + state->requested),
 532                                    state->top_req));
 533
 534                         new_req = cli_readall_send(
 535                                 state->reqs, state->cli, state->fnum,
 536                                 state->start_offset + state->requested,
 537                                 request_thistime);
 538
 539                         if (async_req_nomem(new_req, state->req)) {
 540                                 return;
 541                         }
 542
 543                         new_req->async.fn = cli_pull_read_done;
 544                         new_req->async.priv = pull_req;
 545
 546                         state->reqs[state->top_req].req = new_req;
 547                         state->requested += request_thistime;
 548                 }
 549
 550                 state->top_req = (state->top_req+1) % state->num_reqs;
 551         }
 552
 553         async_req_done(pull_req);
 554 }
 555
 556 NTSTATUS cli_pull_recv(struct async_req *req, SMB_OFF_T *received)
 557 {
 558         struct cli_pull_state *state = talloc_get_type_abort(
 559                 req->private_data, struct cli_pull_state);
 560
 561         SMB_ASSERT(req->state >= ASYNC_REQ_DONE);
 562         if (req->state == ASYNC_REQ_ERROR) {
 563                 return req->status;
 564         }
 565         *received = state->pushed;
 566         return NT_STATUS_OK;
 567 }
 568
 569 NTSTATUS cli_pull(struct cli_state *cli, uint16_t fnum,
 570                   off_t start_offset, SMB_OFF_T size, size_t window_size,
 571                   NTSTATUS (*sink)(char *buf, size_t n, void *priv),
 572                   void *priv, SMB_OFF_T *received)
 573 {
 574         TALLOC_CTX *frame = talloc_stackframe();
 575         struct async_req *req;
 576         NTSTATUS result = NT_STATUS_NO_MEMORY;
 577
 578         if (cli_tmp_event_ctx(frame, cli) == NULL) {
 579                 goto nomem;
 580         }
 581
 582         req = cli_pull_send(frame, cli, fnum, start_offset, size, window_size,
 583                             sink, priv);
 584         if (req == NULL) {
 585                 goto nomem;
 586         }
 587
 588         while (req->state < ASYNC_REQ_DONE) {
 589                 event_loop_once(cli->event_ctx);
 590         }
 591
 592         result = cli_pull_recv(req, received);
 593  nomem:
 594         TALLOC_FREE(frame);
 595         return result;
 596 }
 597
 598 static NTSTATUS cli_read_sink(char *buf, size_t n, void *priv)
 599 {
 600         char **pbuf = (char **)priv;
 601         memcpy(*pbuf, buf, n);
 602         *pbuf += n;
 603         return NT_STATUS_OK;
 604 }
 605
 606 ssize_t cli_read(struct cli_state *cli, int fnum, char *buf,
 607                  off_t offset, size_t size)
 608 {
 609         NTSTATUS status;
 610         SMB_OFF_T ret;
 611
 612         status = cli_pull(cli, fnum, offset, size, size,
 613                           cli_read_sink, &buf, &ret);
 614         if (!NT_STATUS_IS_OK(status)) {
 615                 cli_set_error(cli, status);
 616                 return -1;
 617         }
 618         return ret;
 619 }
 620
 621 /****************************************************************************
 622  Issue a single SMBwrite and don't wait for a reply.
 623 ****************************************************************************/
 624
 625 static bool cli_issue_write(struct cli_state *cli,
 626                                 int fnum,
 627                                 off_t offset,
 628                                 uint16 mode,
 629                                 const char *buf,
 630                                 size_t size,
 631                                 int i)
 632 {
 633         char *p;
 634         bool large_writex = false;
 635         /* We can only do direct writes if not signing and not encrypting. */
 636         bool direct_writes = !client_is_signing_on(cli) && !cli_encryption_on(cli);
 637
 638         if (!direct_writes && size + 1 > cli->bufsize) {
 639                 cli->outbuf = (char *)SMB_REALLOC(cli->outbuf, size + 1024);
 640                 if (!cli->outbuf) {
 641                         return False;
 642                 }
 643                 cli->inbuf = (char *)SMB_REALLOC(cli->inbuf, size + 1024);
 644                 if (cli->inbuf == NULL) {
 645                         SAFE_FREE(cli->outbuf);
 646                         return False;
 647                 }
 648                 cli->bufsize = size + 1024;
 649         }
 650
 651         memset(cli->outbuf,'\0',smb_size);
 652         memset(cli->inbuf,'\0',smb_size);
 653
 654         if (cli->capabilities & CAP_LARGE_FILES) {
 655                 large_writex = True;
 656         }
 657
 658         if (large_writex) {
 659                 cli_set_message(cli->outbuf,14,0,True);
 660         } else {
 661                 cli_set_message(cli->outbuf,12,0,True);
 662         }
 663
 664         SCVAL(cli->outbuf,smb_com,SMBwriteX);
 665         SSVAL(cli->outbuf,smb_tid,cli->cnum);
 666         cli_setup_packet(cli);
 667
 668         SCVAL(cli->outbuf,smb_vwv0,0xFF);
 669         SSVAL(cli->outbuf,smb_vwv2,fnum);
 670
 671         SIVAL(cli->outbuf,smb_vwv3,offset);
 672         SIVAL(cli->outbuf,smb_vwv5,0);
 673         SSVAL(cli->outbuf,smb_vwv7,mode);
 674
 675         SSVAL(cli->outbuf,smb_vwv8,(mode & 0x0008) ? size : 0);
 676         /*
 677          * According to CIFS-TR-1p00, this following field should only
 678          * be set if CAP_LARGE_WRITEX is set. We should check this
 679          * locally. However, this check might already have been
 680          * done by our callers.
 681          */
 682         SSVAL(cli->outbuf,smb_vwv9,(size>>16));
 683         SSVAL(cli->outbuf,smb_vwv10,size);
 684         /* +1 is pad byte. */
 685         SSVAL(cli->outbuf,smb_vwv11,
 686               smb_buf(cli->outbuf) - smb_base(cli->outbuf) + 1);
 687
 688         if (large_writex) {
 689                 SIVAL(cli->outbuf,smb_vwv12,(((SMB_BIG_UINT)offset)>>32) & 0xffffffff);
 690         }
 691
 692         p = smb_base(cli->outbuf) + SVAL(cli->outbuf,smb_vwv11) -1;
 693         *p++ = '\0'; /* pad byte. */
 694         if (!direct_writes) {
 695                 memcpy(p, buf, size);
 696         }
 697         if (size > 0x1FFFF) {
 698                 /* This is a POSIX 14 word large write. */
 699                 set_message_bcc(cli->outbuf, 0); /* Set bcc to zero. */
 700                 _smb_setlen_large(cli->outbuf,smb_size + 28 + 1 /* pad */ + size - 4);
 701         } else {
 702                 cli_setup_bcc(cli, p+size);
 703         }
 704
 705         SSVAL(cli->outbuf,smb_mid,cli->mid + i);
 706
 707         show_msg(cli->outbuf);
 708         if (direct_writes) {
 709                 /* For direct writes we now need to write the data
 710                  * directly out of buf. */
 711                 return cli_send_smb_direct_writeX(cli, buf, size);
 712         } else {
 713                 return cli_send_smb(cli);
 714         }
 715 }
 716
 717 /****************************************************************************
 718   write to a file
 719   write_mode: 0x0001 disallow write cacheing
 720               0x0002 return bytes remaining
 721               0x0004 use raw named pipe protocol
 722               0x0008 start of message mode named pipe protocol
 723 ****************************************************************************/
 724
 725 ssize_t cli_write(struct cli_state *cli,
 726                  int fnum, uint16 write_mode,
 727                  const char *buf, off_t offset, size_t size)
 728 {
 729         ssize_t bwritten = 0;
 730         unsigned int issued = 0;
 731         unsigned int received = 0;
 732         int mpx = 1;
 733         size_t writesize;
 734         int blocks;
 735
 736         if(cli->max_mux > 1) {
 737                 mpx = cli->max_mux-1;
 738         } else {
 739                 mpx = 1;
 740         }
 741
 742         /* Default (small) writesize. */
 743         writesize = (cli->max_xmit - (smb_size+32)) & ~1023;
 744
 745         if (write_mode == 0 &&
 746                         !client_is_signing_on(cli) &&
 747                         !cli_encryption_on(cli) &&
 748                         (cli->posix_capabilities & CIFS_UNIX_LARGE_WRITE_CAP) &&
 749                         (cli->capabilities & CAP_LARGE_FILES)) {
 750                 /* Only do massive writes if we can do them direct
 751                  * with no signing or encrypting - not on a pipe. */
 752                 writesize = CLI_SAMBA_MAX_POSIX_LARGE_WRITEX_SIZE;
 753         } else if ((cli->capabilities & CAP_LARGE_WRITEX) &&
 754                         (strcmp(cli->dev, "LPT1:") != 0)) {
 755
 756                 /* Printer devices are restricted to max_xmit
 757                  * writesize in Vista and XPSP3. */
 758
 759                 if (cli->is_samba) {
 760                         writesize = CLI_SAMBA_MAX_LARGE_WRITEX_SIZE;
 761                 } else if (!client_is_signing_on(cli)) {
 762                         /* Windows restricts signed writes to max_xmit.
 763                          * Found by Volker. */
 764                         writesize = CLI_WINDOWS_MAX_LARGE_WRITEX_SIZE;
 765                 }
 766         }
 767
 768         blocks = (size + (writesize-1)) / writesize;
 769
 770         while (received < blocks) {
 771
 772                 while ((issued - received < mpx) && (issued < blocks)) {
 773                         ssize_t bsent = issued * writesize;
 774                         ssize_t size1 = MIN(writesize, size - bsent);
 775
 776                         if (!cli_issue_write(cli, fnum, offset + bsent,
 777                                         write_mode,
 778                                         buf + bsent,
 779                                         size1, issued))
 780                                 return -1;
 781                         issued++;
 782                 }
 783
 784                 if (!cli_receive_smb(cli)) {
 785                         return bwritten;
 786                 }
 787
 788                 received++;
 789
 790                 if (cli_is_error(cli))
 791                         break;
 792
 793                 bwritten += SVAL(cli->inbuf, smb_vwv2);
 794                 if (writesize > 0xFFFF) {
 795                         bwritten += (((int)(SVAL(cli->inbuf, smb_vwv4)))<<16);
 796                 }
 797         }
 798
 799         while (received < issued && cli_receive_smb(cli)) {
 800                 received++;
 801         }
 802
 803         return bwritten;
 804 }
 805
 806 /****************************************************************************
 807   write to a file using a SMBwrite and not bypassing 0 byte writes
 808 ****************************************************************************/
 809
 810 ssize_t cli_smbwrite(struct cli_state *cli,
 811                      int fnum, char *buf, off_t offset, size_t size1)
 812 {
 813         char *p;
 814         ssize_t total = 0;
 815
 816         do {
 817                 size_t size = MIN(size1, cli->max_xmit - 48);
 818
 819                 memset(cli->outbuf,'\0',smb_size);
 820                 memset(cli->inbuf,'\0',smb_size);
 821
 822                 cli_set_message(cli->outbuf,5, 0,True);
 823
 824                 SCVAL(cli->outbuf,smb_com,SMBwrite);
 825                 SSVAL(cli->outbuf,smb_tid,cli->cnum);
 826                 cli_setup_packet(cli);
 827
 828                 SSVAL(cli->outbuf,smb_vwv0,fnum);
 829                 SSVAL(cli->outbuf,smb_vwv1,size);
 830                 SIVAL(cli->outbuf,smb_vwv2,offset);
 831                 SSVAL(cli->outbuf,smb_vwv4,0);
 832
 833                 p = smb_buf(cli->outbuf);
 834                 *p++ = 1;
 835                 SSVAL(p, 0, size); p += 2;
 836                 memcpy(p, buf + total, size); p += size;
 837
 838                 cli_setup_bcc(cli, p);
 839
 840                 if (!cli_send_smb(cli))
 841                         return -1;
 842
 843                 if (!cli_receive_smb(cli))
 844                         return -1;
 845
 846                 if (cli_is_error(cli))
 847                         return -1;
 848
 849                 size = SVAL(cli->inbuf,smb_vwv0);
 850                 if (size == 0)
 851                         break;
 852
 853                 size1 -= size;
 854                 total += size;
 855                 offset += size;
 856
 857         } while (size1);
 858
 859         return total;
 860 }