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 = cli_request_get(result);
  66
  67         req->data.read.ofs = offset;
  68         req->data.read.size = size;
  69         req->data.read.received = 0;
  70         req->data.read.rcvbuf = NULL;
  71
  72         if ((SMB_BIG_UINT)offset >> 32)
  73                 bigoffset = True;
  74
  75         cli_set_message(req->outbuf, bigoffset ? 12 : 10, 0, False);
  76
  77         SCVAL(req->outbuf,smb_com,SMBreadX);
  78         SSVAL(req->outbuf,smb_tid,cli->cnum);
  79         cli_setup_packet_buf(cli, req->outbuf);
  80
  81         SCVAL(req->outbuf,smb_vwv0,0xFF);
  82         SCVAL(req->outbuf,smb_vwv0+1,0);
  83         SSVAL(req->outbuf,smb_vwv1,0);
  84         SSVAL(req->outbuf,smb_vwv2,fnum);
  85         SIVAL(req->outbuf,smb_vwv3,offset);
  86         SSVAL(req->outbuf,smb_vwv5,size);
  87         SSVAL(req->outbuf,smb_vwv6,size);
  88         SSVAL(req->outbuf,smb_vwv7,(size >> 16));
  89         SSVAL(req->outbuf,smb_vwv8,0);
  90         SSVAL(req->outbuf,smb_vwv9,0);
  91         SSVAL(req->outbuf,smb_mid,req->mid);
  92
  93         if (bigoffset) {
  94                 SIVAL(req->outbuf, smb_vwv10,
  95                       (((SMB_BIG_UINT)offset)>>32) & 0xffffffff);
  96         }
  97
  98         cli_calculate_sign_mac(cli, req->outbuf);
  99
 100         event_fd_set_writeable(cli->fd_event);
 101
 102         if (cli_encryption_on(cli)) {
 103                 NTSTATUS status;
 104                 status = cli_encrypt_message(cli, req->outbuf, &enc_buf);
 105                 if (!NT_STATUS_IS_OK(status)) {
 106                         DEBUG(0, ("Error in encrypting client message. "
 107                                   "Error %s\n", nt_errstr(status)));
 108                         TALLOC_FREE(req);
 109                         return NULL;
 110                 }
 111                 req->outbuf = enc_buf;
 112                 req->enc_state = cli->trans_enc_state;
 113         }
 114
 115         return result;
 116 }
 117
 118 /*
 119  * Pull the data out of a finished async read_and_x request. rcvbuf is
 120  * talloced from the request, so better make sure that you copy it away before
 121  * you talloc_free(req). "rcvbuf" is NOT a talloc_ctx of its own, so do not
 122  * talloc_move it!
 123  */
 124
 125 NTSTATUS cli_read_andx_recv(struct async_req *req, ssize_t *received,
 126                             uint8_t **rcvbuf)
 127 {
 128         struct cli_request *cli_req = cli_request_get(req);
 129         NTSTATUS status;
 130         size_t size;
 131
 132         SMB_ASSERT(req->state >= ASYNC_REQ_DONE);
 133         if (req->state == ASYNC_REQ_ERROR) {
 134                 return req->status;
 135         }
 136
 137         status = cli_pull_error(cli_req->inbuf);
 138
 139         if (!NT_STATUS_IS_OK(status)) {
 140                 return status;
 141         }
 142
 143         /* size is the number of bytes the server returned.
 144          * Might be zero. */
 145         size = SVAL(cli_req->inbuf, smb_vwv5);
 146         size |= (((unsigned int)(SVAL(cli_req->inbuf, smb_vwv7))) << 16);
 147
 148         if (size > cli_req->data.read.size) {
 149                 DEBUG(5,("server returned more than we wanted!\n"));
 150                 return NT_STATUS_UNEXPECTED_IO_ERROR;
 151         }
 152
 153         if (size < 0) {
 154                 DEBUG(5,("read return < 0!\n"));
 155                 return NT_STATUS_UNEXPECTED_IO_ERROR;
 156         }
 157
 158         *rcvbuf = (uint8_t *)
 159                 (smb_base(cli_req->inbuf) + SVAL(cli_req->inbuf, smb_vwv6));
 160         *received = size;
 161         return NT_STATUS_OK;
 162 }
 163
 164 /*
 165  * Parallel read support.
 166  *
 167  * cli_pull sends as many read&x requests as the server would allow via
 168  * max_mux at a time. When replies flow back in, the data is written into
 169  * the callback function "sink" in the right order.
 170  */
 171
 172 struct cli_pull_state {
 173         struct async_req *req;
 174
 175         struct cli_state *cli;
 176         uint16_t fnum;
 177         off_t start_offset;
 178         size_t size;
 179
 180         NTSTATUS (*sink)(char *buf, size_t n, void *priv);
 181         void *priv;
 182
 183         size_t chunk_size;
 184
 185         /*
 186          * Outstanding requests
 187          */
 188         int num_reqs;
 189         struct async_req **reqs;
 190
 191         /*
 192          * For how many bytes did we send requests already?
 193          */
 194         off_t requested;
 195
 196         /*
 197          * Next request index to push into "sink". This walks around the "req"
 198          * array, taking care that the requests are pushed to "sink" in the
 199          * right order. If necessary (i.e. replies don't come in in the right
 200          * order), replies are held back in "reqs".
 201          */
 202         int top_req;
 203
 204         /*
 205          * How many bytes did we push into "sink"?
 206          */
 207
 208         off_t pushed;
 209 };
 210
 211 static char *cli_pull_print(TALLOC_CTX *mem_ctx, struct async_req *req)
 212 {
 213         struct cli_pull_state *state = talloc_get_type_abort(
 214                 req->private_data, struct cli_pull_state);
 215         char *result;
 216
 217         result = async_req_print(mem_ctx, req);
 218         if (result == NULL) {
 219                 return NULL;
 220         }
 221
 222         return talloc_asprintf_append_buffer(
 223                 result, "num_reqs=%d, top_req=%d",
 224                 state->num_reqs, state->top_req);
 225 }
 226
 227 static void cli_pull_read_done(struct async_req *read_req);
 228
 229 /*
 230  * Prepare an async pull request
 231  */
 232
 233 struct async_req *cli_pull_send(TALLOC_CTX *mem_ctx, struct cli_state *cli,
 234                                 uint16_t fnum, off_t start_offset,
 235                                 size_t size, size_t window_size,
 236                                 NTSTATUS (*sink)(char *buf, size_t n,
 237                                                  void *priv),
 238                                 void *priv)
 239 {
 240         struct async_req *result;
 241         struct cli_pull_state *state;
 242         int i;
 243
 244         result = async_req_new(mem_ctx, cli->event_ctx);
 245         if (result == NULL) {
 246                 goto failed;
 247         }
 248         state = talloc(result, struct cli_pull_state);
 249         if (state == NULL) {
 250                 goto failed;
 251         }
 252         result->private_data = state;
 253         result->print = cli_pull_print;
 254         state->req = result;
 255
 256         state->cli = cli;
 257         state->fnum = fnum;
 258         state->start_offset = start_offset;
 259         state->size = size;
 260         state->sink = sink;
 261         state->priv = priv;
 262
 263         state->pushed = 0;
 264         state->top_req = 0;
 265
 266         if (size == 0) {
 267                 if (!async_post_status(result, NT_STATUS_OK)) {
 268                         goto failed;
 269                 }
 270                 return result;
 271         }
 272
 273         state->chunk_size = cli_read_max_bufsize(cli);
 274
 275         state->num_reqs = MAX(window_size/state->chunk_size, 1);
 276         state->num_reqs = MIN(state->num_reqs, cli->max_mux);
 277
 278         state->reqs = TALLOC_ZERO_ARRAY(state, struct async_req *,
 279                                         state->num_reqs);
 280         if (state->reqs == NULL) {
 281                 goto failed;
 282         }
 283
 284         state->requested = 0;
 285
 286         for (i=0; i<state->num_reqs; i++) {
 287                 size_t size_left, request_thistime;
 288
 289                 if (state->requested >= size) {
 290                         state->num_reqs = i;
 291                         break;
 292                 }
 293
 294                 size_left = size - state->requested;
 295                 request_thistime = MIN(size_left, state->chunk_size);
 296
 297                 state->reqs[i] = cli_read_andx_send(
 298                         state->reqs, cli, fnum,
 299                         state->start_offset + state->requested,
 300                         request_thistime);
 301
 302                 if (state->reqs[i] == NULL) {
 303                         goto failed;
 304                 }
 305
 306                 state->reqs[i]->async.fn = cli_pull_read_done;
 307                 state->reqs[i]->async.priv = result;
 308
 309                 state->requested += request_thistime;
 310         }
 311         return result;
 312
 313 failed:
 314         TALLOC_FREE(result);
 315         return NULL;
 316 }
 317
 318 /*
 319  * Handle incoming read replies, push the data into sink and send out new
 320  * requests if necessary.
 321  */
 322
 323 static void cli_pull_read_done(struct async_req *read_req)
 324 {
 325         struct async_req *pull_req = talloc_get_type_abort(
 326                 read_req->async.priv, struct async_req);
 327         struct cli_pull_state *state = talloc_get_type_abort(
 328                 pull_req->private_data, struct cli_pull_state);
 329         struct cli_request *read_state = cli_request_get(read_req);
 330         NTSTATUS status;
 331
 332         status = cli_read_andx_recv(read_req, &read_state->data.read.received,
 333                                     &read_state->data.read.rcvbuf);
 334         if (!NT_STATUS_IS_OK(status)) {
 335                 async_req_error(state->req, status);
 336                 return;
 337         }
 338
 339         /*
 340          * This loop is the one to take care of out-of-order replies. All
 341          * pending requests are in state->reqs, state->reqs[top_req] is the
 342          * one that is to be pushed next. If however a request later than
 343          * top_req is replied to, then we can't push yet. If top_req is
 344          * replied to at a later point then, we need to push all the finished
 345          * requests.
 346          */
 347
 348         while (state->reqs[state->top_req] != NULL) {
 349                 struct cli_request *top_read;
 350
 351                 DEBUG(11, ("cli_pull_read_done: top_req = %d\n",
 352                            state->top_req));
 353
 354                 if (state->reqs[state->top_req]->state < ASYNC_REQ_DONE) {
 355                         DEBUG(11, ("cli_pull_read_done: top request not yet "
 356                                    "done\n"));
 357                         return;
 358                 }
 359
 360                 top_read = cli_request_get(state->reqs[state->top_req]);
 361
 362                 DEBUG(10, ("cli_pull_read_done: Pushing %d bytes, %d already "
 363                            "pushed\n", (int)top_read->data.read.received,
 364                            (int)state->pushed));
 365
 366                 status = state->sink((char *)top_read->data.read.rcvbuf,
 367                                      top_read->data.read.received,
 368                                      state->priv);
 369                 if (!NT_STATUS_IS_OK(status)) {
 370                         async_req_error(state->req, status);
 371                         return;
 372                 }
 373                 state->pushed += top_read->data.read.received;
 374
 375                 TALLOC_FREE(state->reqs[state->top_req]);
 376
 377                 if (state->requested < state->size) {
 378                         struct async_req *new_req;
 379                         size_t size_left, request_thistime;
 380
 381                         size_left = state->size - state->requested;
 382                         request_thistime = MIN(size_left, state->chunk_size);
 383
 384                         DEBUG(10, ("cli_pull_read_done: Requesting %d bytes "
 385                                    "at %d, position %d\n",
 386                                    (int)request_thistime,
 387                                    (int)(state->start_offset
 388                                          + state->requested),
 389                                    state->top_req));
 390
 391                         new_req = cli_read_andx_send(
 392                                 state->reqs, state->cli, state->fnum,
 393                                 state->start_offset + state->requested,
 394                                 request_thistime);
 395
 396                         if (async_req_nomem(new_req, state->req)) {
 397                                 return;
 398                         }
 399
 400                         new_req->async.fn = cli_pull_read_done;
 401                         new_req->async.priv = pull_req;
 402
 403                         state->reqs[state->top_req] = new_req;
 404                         state->requested += request_thistime;
 405                 }
 406
 407                 state->top_req = (state->top_req+1) % state->num_reqs;
 408         }
 409
 410         async_req_done(pull_req);
 411 }
 412
 413 NTSTATUS cli_pull_recv(struct async_req *req, ssize_t *received)
 414 {
 415         struct cli_pull_state *state = talloc_get_type_abort(
 416                 req->private_data, struct cli_pull_state);
 417
 418         SMB_ASSERT(req->state >= ASYNC_REQ_DONE);
 419         if (req->state == ASYNC_REQ_ERROR) {
 420                 return req->status;
 421         }
 422         *received = state->pushed;
 423         return NT_STATUS_OK;
 424 }
 425
 426 NTSTATUS cli_pull(struct cli_state *cli, uint16_t fnum,
 427                   off_t start_offset, size_t size, size_t window_size,
 428                   NTSTATUS (*sink)(char *buf, size_t n, void *priv),
 429                   void *priv, ssize_t *received)
 430 {
 431         TALLOC_CTX *frame = talloc_stackframe();
 432         struct async_req *req;
 433         NTSTATUS result = NT_STATUS_NO_MEMORY;
 434
 435         if (cli_tmp_event_ctx(frame, cli) == NULL) {
 436                 goto nomem;
 437         }
 438
 439         req = cli_pull_send(frame, cli, fnum, start_offset, size, window_size,
 440                             sink, priv);
 441         if (req == NULL) {
 442                 goto nomem;
 443         }
 444
 445         while (req->state < ASYNC_REQ_DONE) {
 446                 event_loop_once(cli->event_ctx);
 447         }
 448
 449         result = cli_pull_recv(req, received);
 450  nomem:
 451         TALLOC_FREE(frame);
 452         return result;
 453 }
 454
 455 static NTSTATUS cli_read_sink(char *buf, size_t n, void *priv)
 456 {
 457         char **pbuf = (char **)priv;
 458         memcpy(*pbuf, buf, n);
 459         *pbuf += n;
 460         return NT_STATUS_OK;
 461 }
 462
 463 ssize_t cli_read(struct cli_state *cli, int fnum, char *buf,
 464                  off_t offset, size_t size)
 465 {
 466         NTSTATUS status;
 467         ssize_t ret;
 468
 469         status = cli_pull(cli, fnum, offset, size, size,
 470                           cli_read_sink, &buf, &ret);
 471         if (!NT_STATUS_IS_OK(status)) {
 472                 cli_set_error(cli, status);
 473                 return -1;
 474         }
 475         return ret;
 476 }
 477
 478 #if 0  /* relies on client_receive_smb(), now a static in libsmb/clientgen.c */
 479
 480 /* This call is INCOMPATIBLE with SMB signing.  If you remove the #if 0
 481    you must fix ensure you don't attempt to sign the packets - data
 482    *will* be currupted */
 483
 484 /****************************************************************************
 485 Issue a single SMBreadraw and don't wait for a reply.
 486 ****************************************************************************/
 487
 488 static bool cli_issue_readraw(struct cli_state *cli, int fnum, off_t offset,
 489                            size_t size, int i)
 490 {
 491
 492         if (!cli->sign_info.use_smb_signing) {
 493                 DEBUG(0, ("Cannot use readraw and SMB Signing\n"));
 494                 return False;
 495         }
 496
 497         memset(cli->outbuf,'\0',smb_size);
 498         memset(cli->inbuf,'\0',smb_size);
 499
 500         cli_set_message(cli->outbuf,10,0,True);
 501
 502         SCVAL(cli->outbuf,smb_com,SMBreadbraw);
 503         SSVAL(cli->outbuf,smb_tid,cli->cnum);
 504         cli_setup_packet(cli);
 505
 506         SSVAL(cli->outbuf,smb_vwv0,fnum);
 507         SIVAL(cli->outbuf,smb_vwv1,offset);
 508         SSVAL(cli->outbuf,smb_vwv2,size);
 509         SSVAL(cli->outbuf,smb_vwv3,size);
 510         SSVAL(cli->outbuf,smb_mid,cli->mid + i);
 511
 512         return cli_send_smb(cli);
 513 }
 514
 515 /****************************************************************************
 516  Tester for the readraw call.
 517 ****************************************************************************/
 518
 519 ssize_t cli_readraw(struct cli_state *cli, int fnum, char *buf, off_t offset, size_t size)
 520 {
 521         char *p;
 522         int size2;
 523         size_t readsize;
 524         ssize_t total = 0;
 525
 526         if (size == 0)
 527                 return 0;
 528
 529         /*
 530          * Set readsize to the maximum size we can handle in one readraw.
 531          */
 532
 533         readsize = 0xFFFF;
 534
 535         while (total < size) {
 536                 readsize = MIN(readsize, size-total);
 537
 538                 /* Issue a read and receive a reply */
 539
 540                 if (!cli_issue_readraw(cli, fnum, offset, readsize, 0))
 541                         return -1;
 542
 543                 if (!client_receive_smb(cli->fd, cli->inbuf, cli->timeout))
 544                         return -1;
 545
 546                 size2 = smb_len(cli->inbuf);
 547
 548                 if (size2 > readsize) {
 549                         DEBUG(5,("server returned more than we wanted!\n"));
 550                         return -1;
 551                 } else if (size2 < 0) {
 552                         DEBUG(5,("read return < 0!\n"));
 553                         return -1;
 554                 }
 555
 556                 /* Copy data into buffer */
 557
 558                 if (size2) {
 559                         p = cli->inbuf + 4;
 560                         memcpy(buf + total, p, size2);
 561                 }
 562
 563                 total += size2;
 564                 offset += size2;
 565
 566                 /*
 567                  * If the server returned less than we asked for we're at EOF.
 568                  */
 569
 570                 if (size2 < readsize)
 571                         break;
 572         }
 573
 574         return total;
 575 }
 576 #endif
 577
 578 /****************************************************************************
 579  Issue a single SMBwrite and don't wait for a reply.
 580 ****************************************************************************/
 581
 582 static bool cli_issue_write(struct cli_state *cli,
 583                                 int fnum,
 584                                 off_t offset,
 585                                 uint16 mode,
 586                                 const char *buf,
 587                                 size_t size,
 588                                 int i)
 589 {
 590         char *p;
 591         bool large_writex = false;
 592         /* We can only do direct writes if not signing and not encrypting. */
 593         bool direct_writes = !client_is_signing_on(cli) && !cli_encryption_on(cli);
 594
 595         if (!direct_writes && size + 1 > cli->bufsize) {
 596                 cli->outbuf = (char *)SMB_REALLOC(cli->outbuf, size + 1024);
 597                 if (!cli->outbuf) {
 598                         return False;
 599                 }
 600                 cli->inbuf = (char *)SMB_REALLOC(cli->inbuf, size + 1024);
 601                 if (cli->inbuf == NULL) {
 602                         SAFE_FREE(cli->outbuf);
 603                         return False;
 604                 }
 605                 cli->bufsize = size + 1024;
 606         }
 607
 608         memset(cli->outbuf,'\0',smb_size);
 609         memset(cli->inbuf,'\0',smb_size);
 610
 611         if (cli->capabilities & CAP_LARGE_FILES) {
 612                 large_writex = True;
 613         }
 614
 615         if (large_writex) {
 616                 cli_set_message(cli->outbuf,14,0,True);
 617         } else {
 618                 cli_set_message(cli->outbuf,12,0,True);
 619         }
 620
 621         SCVAL(cli->outbuf,smb_com,SMBwriteX);
 622         SSVAL(cli->outbuf,smb_tid,cli->cnum);
 623         cli_setup_packet(cli);
 624
 625         SCVAL(cli->outbuf,smb_vwv0,0xFF);
 626         SSVAL(cli->outbuf,smb_vwv2,fnum);
 627
 628         SIVAL(cli->outbuf,smb_vwv3,offset);
 629         SIVAL(cli->outbuf,smb_vwv5,0);
 630         SSVAL(cli->outbuf,smb_vwv7,mode);
 631
 632         SSVAL(cli->outbuf,smb_vwv8,(mode & 0x0008) ? size : 0);
 633         /*
 634          * According to CIFS-TR-1p00, this following field should only
 635          * be set if CAP_LARGE_WRITEX is set. We should check this
 636          * locally. However, this check might already have been
 637          * done by our callers.
 638          */
 639         SSVAL(cli->outbuf,smb_vwv9,(size>>16));
 640         SSVAL(cli->outbuf,smb_vwv10,size);
 641         /* +1 is pad byte. */
 642         SSVAL(cli->outbuf,smb_vwv11,
 643               smb_buf(cli->outbuf) - smb_base(cli->outbuf) + 1);
 644
 645         if (large_writex) {
 646                 SIVAL(cli->outbuf,smb_vwv12,(((SMB_BIG_UINT)offset)>>32) & 0xffffffff);
 647         }
 648
 649         p = smb_base(cli->outbuf) + SVAL(cli->outbuf,smb_vwv11) -1;
 650         *p++ = '\0'; /* pad byte. */
 651         if (!direct_writes) {
 652                 memcpy(p, buf, size);
 653         }
 654         if (size > 0x1FFFF) {
 655                 /* This is a POSIX 14 word large write. */
 656                 set_message_bcc(cli->outbuf, 0); /* Set bcc to zero. */
 657                 _smb_setlen_large(cli->outbuf,smb_size + 28 + 1 /* pad */ + size - 4);
 658         } else {
 659                 cli_setup_bcc(cli, p+size);
 660         }
 661
 662         SSVAL(cli->outbuf,smb_mid,cli->mid + i);
 663
 664         show_msg(cli->outbuf);
 665         if (direct_writes) {
 666                 /* For direct writes we now need to write the data
 667                  * directly out of buf. */
 668                 return cli_send_smb_direct_writeX(cli, buf, size);
 669         } else {
 670                 return cli_send_smb(cli);
 671         }
 672 }
 673
 674 /****************************************************************************
 675   write to a file
 676   write_mode: 0x0001 disallow write cacheing
 677               0x0002 return bytes remaining
 678               0x0004 use raw named pipe protocol
 679               0x0008 start of message mode named pipe protocol
 680 ****************************************************************************/
 681
 682 ssize_t cli_write(struct cli_state *cli,
 683                  int fnum, uint16 write_mode,
 684                  const char *buf, off_t offset, size_t size)
 685 {
 686         ssize_t bwritten = 0;
 687         unsigned int issued = 0;
 688         unsigned int received = 0;
 689         int mpx = 1;
 690         size_t writesize;
 691         int blocks;
 692
 693         if(cli->max_mux > 1) {
 694                 mpx = cli->max_mux-1;
 695         } else {
 696                 mpx = 1;
 697         }
 698
 699         /* Default (small) writesize. */
 700         writesize = (cli->max_xmit - (smb_size+32)) & ~1023;
 701
 702         if (write_mode == 0 &&
 703                         !client_is_signing_on(cli) &&
 704                         !cli_encryption_on(cli) &&
 705                         (cli->posix_capabilities & CIFS_UNIX_LARGE_WRITE_CAP) &&
 706                         (cli->capabilities & CAP_LARGE_FILES)) {
 707                 /* Only do massive writes if we can do them direct
 708                  * with no signing or encrypting - not on a pipe. */
 709                 writesize = CLI_SAMBA_MAX_POSIX_LARGE_WRITEX_SIZE;
 710         } else if (cli->capabilities & CAP_LARGE_WRITEX) {
 711                 if (cli->is_samba) {
 712                         writesize = CLI_SAMBA_MAX_LARGE_WRITEX_SIZE;
 713                 } else if (!client_is_signing_on(cli)) {
 714                         /* Windows restricts signed writes to max_xmit.
 715                          * Found by Volker. */
 716                         writesize = CLI_WINDOWS_MAX_LARGE_WRITEX_SIZE;
 717                 }
 718         }
 719
 720         blocks = (size + (writesize-1)) / writesize;
 721
 722         while (received < blocks) {
 723
 724                 while ((issued - received < mpx) && (issued < blocks)) {
 725                         ssize_t bsent = issued * writesize;
 726                         ssize_t size1 = MIN(writesize, size - bsent);
 727
 728                         if (!cli_issue_write(cli, fnum, offset + bsent,
 729                                         write_mode,
 730                                         buf + bsent,
 731                                         size1, issued))
 732                                 return -1;
 733                         issued++;
 734                 }
 735
 736                 if (!cli_receive_smb(cli)) {
 737                         return bwritten;
 738                 }
 739
 740                 received++;
 741
 742                 if (cli_is_error(cli))
 743                         break;
 744
 745                 bwritten += SVAL(cli->inbuf, smb_vwv2);
 746                 bwritten += (((int)(SVAL(cli->inbuf, smb_vwv4)))<<16);
 747         }
 748
 749         while (received < issued && cli_receive_smb(cli)) {
 750                 received++;
 751         }
 752
 753         return bwritten;
 754 }
 755
 756 /****************************************************************************
 757   write to a file using a SMBwrite and not bypassing 0 byte writes
 758 ****************************************************************************/
 759
 760 ssize_t cli_smbwrite(struct cli_state *cli,
 761                      int fnum, char *buf, off_t offset, size_t size1)
 762 {
 763         char *p;
 764         ssize_t total = 0;
 765
 766         do {
 767                 size_t size = MIN(size1, cli->max_xmit - 48);
 768
 769                 memset(cli->outbuf,'\0',smb_size);
 770                 memset(cli->inbuf,'\0',smb_size);
 771
 772                 cli_set_message(cli->outbuf,5, 0,True);
 773
 774                 SCVAL(cli->outbuf,smb_com,SMBwrite);
 775                 SSVAL(cli->outbuf,smb_tid,cli->cnum);
 776                 cli_setup_packet(cli);
 777
 778                 SSVAL(cli->outbuf,smb_vwv0,fnum);
 779                 SSVAL(cli->outbuf,smb_vwv1,size);
 780                 SIVAL(cli->outbuf,smb_vwv2,offset);
 781                 SSVAL(cli->outbuf,smb_vwv4,0);
 782
 783                 p = smb_buf(cli->outbuf);
 784                 *p++ = 1;
 785                 SSVAL(p, 0, size); p += 2;
 786                 memcpy(p, buf + total, size); p += size;
 787
 788                 cli_setup_bcc(cli, p);
 789
 790                 if (!cli_send_smb(cli))
 791                         return -1;
 792
 793                 if (!cli_receive_smb(cli))
 794                         return -1;
 795
 796                 if (cli_is_error(cli))
 797                         return -1;
 798
 799                 size = SVAL(cli->inbuf,smb_vwv0);
 800                 if (size == 0)
 801                         break;
 802
 803                 size1 -= size;
 804                 total += size;
 805                 offset += size;
 806
 807         } while (size1);
 808
 809         return total;
 810 }