source3/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 Issue a single SMBread and don't wait for a reply.
  24 ****************************************************************************/
  25
  26 static bool cli_issue_read(struct cli_state *cli, int fnum, off_t offset,
  27                            size_t size, int i)
  28 {
  29         bool bigoffset = False;
  30
  31         memset(cli->outbuf,'\0',smb_size);
  32         memset(cli->inbuf,'\0',smb_size);
  33
  34         if ((SMB_BIG_UINT)offset >> 32)
  35                 bigoffset = True;
  36
  37         cli_set_message(cli->outbuf,bigoffset ? 12 : 10,0,True);
  38
  39         SCVAL(cli->outbuf,smb_com,SMBreadX);
  40         SSVAL(cli->outbuf,smb_tid,cli->cnum);
  41         cli_setup_packet(cli);
  42
  43         SCVAL(cli->outbuf,smb_vwv0,0xFF);
  44         SSVAL(cli->outbuf,smb_vwv2,fnum);
  45         SIVAL(cli->outbuf,smb_vwv3,offset);
  46         SSVAL(cli->outbuf,smb_vwv5,size);
  47         SSVAL(cli->outbuf,smb_vwv6,size);
  48         SSVAL(cli->outbuf,smb_vwv7,(size >> 16));
  49         SSVAL(cli->outbuf,smb_mid,cli->mid + i);
  50
  51         if (bigoffset) {
  52                 SIVAL(cli->outbuf,smb_vwv10,(((SMB_BIG_UINT)offset)>>32) & 0xffffffff);
  53         }
  54
  55         return cli_send_smb(cli);
  56 }
  57
  58 /****************************************************************************
  59   Read size bytes at offset offset using SMBreadX.
  60 ****************************************************************************/
  61
  62 ssize_t cli_read(struct cli_state *cli, int fnum, char *buf, off_t offset, size_t size)
  63 {
  64         char *p;
  65         size_t size2;
  66         size_t readsize;
  67         ssize_t total = 0;
  68         /* We can only do direct reads if not signing or encrypting. */
  69         bool direct_reads = !client_is_signing_on(cli) && !cli_encryption_on(cli);
  70
  71         if (size == 0)
  72                 return 0;
  73
  74         /*
  75          * Set readsize to the maximum size we can handle in one readX,
  76          * rounded down to a multiple of 1024.
  77          */
  78
  79         if (client_is_signing_on(cli) == false &&
  80                         cli_encryption_on(cli) == false &&
  81                         (cli->posix_capabilities & CIFS_UNIX_LARGE_READ_CAP)) {
  82                 readsize = CLI_SAMBA_MAX_POSIX_LARGE_READX_SIZE;
  83         } else if (cli->capabilities & CAP_LARGE_READX) {
  84                 if (cli->is_samba) {
  85                         readsize = CLI_SAMBA_MAX_LARGE_READX_SIZE;
  86                 } else {
  87                         readsize = CLI_WINDOWS_MAX_LARGE_READX_SIZE;
  88                 }
  89         } else {
  90                 readsize = (cli->max_xmit - (smb_size+32)) & ~1023;
  91         }
  92
  93         while (total < size) {
  94                 readsize = MIN(readsize, size-total);
  95
  96                 /* Issue a read and receive a reply */
  97
  98                 if (!cli_issue_read(cli, fnum, offset, readsize, 0))
  99                         return -1;
 100
 101                 if (direct_reads) {
 102                         if (!cli_receive_smb_readX_header(cli))
 103                                 return -1;
 104                 } else {
 105                         if (!cli_receive_smb(cli))
 106                                 return -1;
 107                 }
 108
 109                 /* Check for error.  Make sure to check for DOS and NT
 110                    errors. */
 111
 112                 if (cli_is_error(cli)) {
 113                         bool recoverable_error = False;
 114                         NTSTATUS status = NT_STATUS_OK;
 115                         uint8 eclass = 0;
 116                         uint32 ecode = 0;
 117
 118                         if (cli_is_nt_error(cli))
 119                                 status = cli_nt_error(cli);
 120                         else
 121                                 cli_dos_error(cli, &eclass, &ecode);
 122
 123                         /*
 124                          * ERRDOS ERRmoredata or STATUS_MORE_ENRTIES is a
 125                          * recoverable error, plus we have valid data in the
 126                          * packet so don't error out here.
 127                          */
 128
 129                         if ((eclass == ERRDOS && ecode == ERRmoredata) ||
 130                             NT_STATUS_V(status) == NT_STATUS_V(STATUS_MORE_ENTRIES))
 131                                 recoverable_error = True;
 132
 133                         if (!recoverable_error)
 134                                 return -1;
 135                 }
 136
 137                 /* size2 is the number of bytes the server returned.
 138                  * Might be zero. */
 139                 size2 = SVAL(cli->inbuf, smb_vwv5);
 140                 size2 |= (((unsigned int)(SVAL(cli->inbuf, smb_vwv7))) << 16);
 141
 142                 if (size2 > readsize) {
 143                         DEBUG(5,("server returned more than we wanted!\n"));
 144                         return -1;
 145                 } else if (size2 < 0) {
 146                         DEBUG(5,("read return < 0!\n"));
 147                         return -1;
 148                 }
 149
 150                 if (size2) {
 151                         /* smb_vwv6 is the offset in the packet of the returned
 152                          * data bytes. Only valid if size2 != 0. */
 153
 154                         if (!direct_reads) {
 155                                 /* Copy data into buffer */
 156                                 p = smb_base(cli->inbuf) + SVAL(cli->inbuf,smb_vwv6);
 157                                 memcpy(buf + total, p, size2);
 158                         } else {
 159                                 /* Ensure the remaining data matches the return size. */
 160                                 ssize_t toread = smb_len_large(cli->inbuf) - SVAL(cli->inbuf,smb_vwv6);
 161
 162                                 /* Ensure the size is correct. */
 163                                 if (toread != size2) {
 164                                         DEBUG(5,("direct read logic fail toread (%d) != size2 (%u)\n",
 165                                                 (int)toread, (unsigned int)size2 ));
 166                                         return -1;
 167                                 }
 168
 169                                 /* Read data directly into buffer */
 170                                 toread = cli_receive_smb_data(cli,buf+total,size2);
 171                                 if (toread != size2) {
 172                                         DEBUG(5,("direct read read failure toread (%d) != size2 (%u)\n",
 173                                                 (int)toread, (unsigned int)size2 ));
 174                                         return -1;
 175                                 }
 176                         }
 177                 }
 178
 179                 total += size2;
 180                 offset += size2;
 181
 182                 /*
 183                  * If the server returned less than we asked for we're at EOF.
 184                  */
 185
 186                 if (size2 < readsize)
 187                         break;
 188         }
 189
 190         return total;
 191 }
 192
 193 #if 0  /* relies on client_receive_smb(), now a static in libsmb/clientgen.c */
 194
 195 /* This call is INCOMPATIBLE with SMB signing.  If you remove the #if 0
 196    you must fix ensure you don't attempt to sign the packets - data
 197    *will* be currupted */
 198
 199 /****************************************************************************
 200 Issue a single SMBreadraw and don't wait for a reply.
 201 ****************************************************************************/
 202
 203 static bool cli_issue_readraw(struct cli_state *cli, int fnum, off_t offset,
 204                            size_t size, int i)
 205 {
 206
 207         if (!cli->sign_info.use_smb_signing) {
 208                 DEBUG(0, ("Cannot use readraw and SMB Signing\n"));
 209                 return False;
 210         }
 211
 212         memset(cli->outbuf,'\0',smb_size);
 213         memset(cli->inbuf,'\0',smb_size);
 214
 215         cli_set_message(cli->outbuf,10,0,True);
 216
 217         SCVAL(cli->outbuf,smb_com,SMBreadbraw);
 218         SSVAL(cli->outbuf,smb_tid,cli->cnum);
 219         cli_setup_packet(cli);
 220
 221         SSVAL(cli->outbuf,smb_vwv0,fnum);
 222         SIVAL(cli->outbuf,smb_vwv1,offset);
 223         SSVAL(cli->outbuf,smb_vwv2,size);
 224         SSVAL(cli->outbuf,smb_vwv3,size);
 225         SSVAL(cli->outbuf,smb_mid,cli->mid + i);
 226
 227         return cli_send_smb(cli);
 228 }
 229
 230 /****************************************************************************
 231  Tester for the readraw call.
 232 ****************************************************************************/
 233
 234 ssize_t cli_readraw(struct cli_state *cli, int fnum, char *buf, off_t offset, size_t size)
 235 {
 236         char *p;
 237         int size2;
 238         size_t readsize;
 239         ssize_t total = 0;
 240
 241         if (size == 0)
 242                 return 0;
 243
 244         /*
 245          * Set readsize to the maximum size we can handle in one readraw.
 246          */
 247
 248         readsize = 0xFFFF;
 249
 250         while (total < size) {
 251                 readsize = MIN(readsize, size-total);
 252
 253                 /* Issue a read and receive a reply */
 254
 255                 if (!cli_issue_readraw(cli, fnum, offset, readsize, 0))
 256                         return -1;
 257
 258                 if (!client_receive_smb(cli->fd, cli->inbuf, cli->timeout))
 259                         return -1;
 260
 261                 size2 = smb_len(cli->inbuf);
 262
 263                 if (size2 > readsize) {
 264                         DEBUG(5,("server returned more than we wanted!\n"));
 265                         return -1;
 266                 } else if (size2 < 0) {
 267                         DEBUG(5,("read return < 0!\n"));
 268                         return -1;
 269                 }
 270
 271                 /* Copy data into buffer */
 272
 273                 if (size2) {
 274                         p = cli->inbuf + 4;
 275                         memcpy(buf + total, p, size2);
 276                 }
 277
 278                 total += size2;
 279                 offset += size2;
 280
 281                 /*
 282                  * If the server returned less than we asked for we're at EOF.
 283                  */
 284
 285                 if (size2 < readsize)
 286                         break;
 287         }
 288
 289         return total;
 290 }
 291 #endif
 292
 293 /****************************************************************************
 294  Issue a single SMBwrite and don't wait for a reply.
 295 ****************************************************************************/
 296
 297 static bool cli_issue_write(struct cli_state *cli,
 298                                 int fnum,
 299                                 off_t offset,
 300                                 uint16 mode,
 301                                 const char *buf,
 302                                 size_t size,
 303                                 int i)
 304 {
 305         char *p;
 306         bool large_writex = false;
 307         /* We can only do direct writes if not signing and not encrypting. */
 308         bool direct_writes = !client_is_signing_on(cli) && !cli_encryption_on(cli);
 309
 310         if (!direct_writes && size + 1 > cli->bufsize) {
 311                 cli->outbuf = (char *)SMB_REALLOC(cli->outbuf, size + 1024);
 312                 if (!cli->outbuf) {
 313                         return False;
 314                 }
 315                 cli->inbuf = (char *)SMB_REALLOC(cli->inbuf, size + 1024);
 316                 if (cli->inbuf == NULL) {
 317                         SAFE_FREE(cli->outbuf);
 318                         return False;
 319                 }
 320                 cli->bufsize = size + 1024;
 321         }
 322
 323         memset(cli->outbuf,'\0',smb_size);
 324         memset(cli->inbuf,'\0',smb_size);
 325
 326         if (cli->capabilities & CAP_LARGE_FILES) {
 327                 large_writex = True;
 328         }
 329
 330         if (large_writex) {
 331                 cli_set_message(cli->outbuf,14,0,True);
 332         } else {
 333                 cli_set_message(cli->outbuf,12,0,True);
 334         }
 335
 336         SCVAL(cli->outbuf,smb_com,SMBwriteX);
 337         SSVAL(cli->outbuf,smb_tid,cli->cnum);
 338         cli_setup_packet(cli);
 339
 340         SCVAL(cli->outbuf,smb_vwv0,0xFF);
 341         SSVAL(cli->outbuf,smb_vwv2,fnum);
 342
 343         SIVAL(cli->outbuf,smb_vwv3,offset);
 344         SIVAL(cli->outbuf,smb_vwv5,0);
 345         SSVAL(cli->outbuf,smb_vwv7,mode);
 346
 347         SSVAL(cli->outbuf,smb_vwv8,(mode & 0x0008) ? size : 0);
 348         /*
 349          * According to CIFS-TR-1p00, this following field should only
 350          * be set if CAP_LARGE_WRITEX is set. We should check this
 351          * locally. However, this check might already have been
 352          * done by our callers.
 353          */
 354         SSVAL(cli->outbuf,smb_vwv9,(size>>16));
 355         SSVAL(cli->outbuf,smb_vwv10,size);
 356         /* +1 is pad byte. */
 357         SSVAL(cli->outbuf,smb_vwv11,
 358               smb_buf(cli->outbuf) - smb_base(cli->outbuf) + 1);
 359
 360         if (large_writex) {
 361                 SIVAL(cli->outbuf,smb_vwv12,(((SMB_BIG_UINT)offset)>>32) & 0xffffffff);
 362         }
 363
 364         p = smb_base(cli->outbuf) + SVAL(cli->outbuf,smb_vwv11) -1;
 365         *p++ = '\0'; /* pad byte. */
 366         if (!direct_writes) {
 367                 memcpy(p, buf, size);
 368         }
 369         if (size > 0x1FFFF) {
 370                 /* This is a POSIX 14 word large write. */
 371                 set_message_bcc(cli->outbuf, 0); /* Set bcc to zero. */
 372                 _smb_setlen_large(cli->outbuf,smb_size + 28 + 1 /* pad */ + size - 4);
 373         } else {
 374                 cli_setup_bcc(cli, p+size);
 375         }
 376
 377         SSVAL(cli->outbuf,smb_mid,cli->mid + i);
 378
 379         show_msg(cli->outbuf);
 380         if (direct_writes) {
 381                 /* For direct writes we now need to write the data
 382                  * directly out of buf. */
 383                 return cli_send_smb_direct_writeX(cli, buf, size);
 384         } else {
 385                 return cli_send_smb(cli);
 386         }
 387 }
 388
 389 /****************************************************************************
 390   write to a file
 391   write_mode: 0x0001 disallow write cacheing
 392               0x0002 return bytes remaining
 393               0x0004 use raw named pipe protocol
 394               0x0008 start of message mode named pipe protocol
 395 ****************************************************************************/
 396
 397 ssize_t cli_write(struct cli_state *cli,
 398                  int fnum, uint16 write_mode,
 399                  const char *buf, off_t offset, size_t size)
 400 {
 401         ssize_t bwritten = 0;
 402         unsigned int issued = 0;
 403         unsigned int received = 0;
 404         int mpx = 1;
 405         size_t writesize;
 406         int blocks;
 407
 408         if(cli->max_mux > 1) {
 409                 mpx = cli->max_mux-1;
 410         } else {
 411                 mpx = 1;
 412         }
 413
 414         /* Default (small) writesize. */
 415         writesize = (cli->max_xmit - (smb_size+32)) & ~1023;
 416
 417         if (write_mode == 0 &&
 418                         !client_is_signing_on(cli) &&
 419                         !cli_encryption_on(cli) &&
 420                         (cli->posix_capabilities & CIFS_UNIX_LARGE_WRITE_CAP) &&
 421                         (cli->capabilities & CAP_LARGE_FILES)) {
 422                 /* Only do massive writes if we can do them direct
 423                  * with no signing or encrypting - not on a pipe. */
 424                 writesize = CLI_SAMBA_MAX_POSIX_LARGE_WRITEX_SIZE;
 425         } else if (cli->capabilities & CAP_LARGE_WRITEX) {
 426                 if (cli->is_samba) {
 427                         writesize = CLI_SAMBA_MAX_LARGE_WRITEX_SIZE;
 428                 } else if (!client_is_signing_on(cli)) {
 429                         /* Windows restricts signed writes to max_xmit.
 430                          * Found by Volker. */
 431                         writesize = CLI_WINDOWS_MAX_LARGE_WRITEX_SIZE;
 432                 }
 433         }
 434
 435         blocks = (size + (writesize-1)) / writesize;
 436
 437         while (received < blocks) {
 438
 439                 while ((issued - received < mpx) && (issued < blocks)) {
 440                         ssize_t bsent = issued * writesize;
 441                         ssize_t size1 = MIN(writesize, size - bsent);
 442
 443                         if (!cli_issue_write(cli, fnum, offset + bsent,
 444                                         write_mode,
 445                                         buf + bsent,
 446                                         size1, issued))
 447                                 return -1;
 448                         issued++;
 449                 }
 450
 451                 if (!cli_receive_smb(cli)) {
 452                         return bwritten;
 453                 }
 454
 455                 received++;
 456
 457                 if (cli_is_error(cli))
 458                         break;
 459
 460                 bwritten += SVAL(cli->inbuf, smb_vwv2);
 461                 bwritten += (((int)(SVAL(cli->inbuf, smb_vwv4)))<<16);
 462         }
 463
 464         while (received < issued && cli_receive_smb(cli)) {
 465                 received++;
 466         }
 467
 468         return bwritten;
 469 }
 470
 471 /****************************************************************************
 472   write to a file using a SMBwrite and not bypassing 0 byte writes
 473 ****************************************************************************/
 474
 475 ssize_t cli_smbwrite(struct cli_state *cli,
 476                      int fnum, char *buf, off_t offset, size_t size1)
 477 {
 478         char *p;
 479         ssize_t total = 0;
 480
 481         do {
 482                 size_t size = MIN(size1, cli->max_xmit - 48);
 483
 484                 memset(cli->outbuf,'\0',smb_size);
 485                 memset(cli->inbuf,'\0',smb_size);
 486
 487                 cli_set_message(cli->outbuf,5, 0,True);
 488
 489                 SCVAL(cli->outbuf,smb_com,SMBwrite);
 490                 SSVAL(cli->outbuf,smb_tid,cli->cnum);
 491                 cli_setup_packet(cli);
 492
 493                 SSVAL(cli->outbuf,smb_vwv0,fnum);
 494                 SSVAL(cli->outbuf,smb_vwv1,size);
 495                 SIVAL(cli->outbuf,smb_vwv2,offset);
 496                 SSVAL(cli->outbuf,smb_vwv4,0);
 497
 498                 p = smb_buf(cli->outbuf);
 499                 *p++ = 1;
 500                 SSVAL(p, 0, size); p += 2;
 501                 memcpy(p, buf + total, size); p += size;
 502
 503                 cli_setup_bcc(cli, p);
 504
 505                 if (!cli_send_smb(cli))
 506                         return -1;
 507
 508                 if (!cli_receive_smb(cli))
 509                         return -1;
 510
 511                 if (cli_is_error(cli))
 512                         return -1;
 513
 514                 size = SVAL(cli->inbuf,smb_vwv0);
 515                 if (size == 0)
 516                         break;
 517
 518                 size1 -= size;
 519                 total += size;
 520                 offset += size;
 521
 522         } while (size1);
 523
 524         return total;
 525 }