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