source4/client/cifsddio.c

   1 /*
   2    CIFSDD - dd for SMB.
   3    IO routines, generic and specific.
   4
   5    Copyright (C) James Peach 2005-2006
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "system/filesys.h"
  23 #include "libcli/raw/libcliraw.h"
  24 #include "libcli/libcli.h"
  25 #include "lib/cmdline/popt_common.h"
  26
  27 #include "cifsdd.h"
  28
  29 /* ------------------------------------------------------------------------- */
  30 /* UNIX file descriptor IO.                                                  */
  31 /* ------------------------------------------------------------------------- */
  32
  33 struct fd_handle
  34 {
  35         struct dd_iohandle      h;
  36         int                     fd;
  37 };
  38
  39 #define IO_HANDLE_TO_FD(h) (((struct fd_handle *)(h))->fd)
  40
  41 static BOOL fd_seek_func(void * handle, uint64_t offset)
  42 {
  43         ssize_t ret;
  44
  45         ret = lseek(IO_HANDLE_TO_FD(handle), offset, SEEK_SET);
  46         if (ret < 0) {
  47                 fprintf(stderr, "%s: seek failed: %s\n",
  48                                 PROGNAME, strerror(errno));
  49                 return(False);
  50         }
  51
  52         return(True);
  53 }
  54
  55 static BOOL fd_read_func(void * handle,
  56                         uint8_t * buf,
  57                         uint64_t wanted,
  58                         uint64_t * actual)
  59 {
  60         ssize_t ret;
  61
  62         ret = read(IO_HANDLE_TO_FD(handle), buf, wanted);
  63         if (ret < 0) {
  64                 fprintf(stderr, "%s: %llu byte read failed: %s\n",
  65                                 PROGNAME, (unsigned long long)wanted,
  66                                 strerror(errno));
  67                 return(False);
  68         }
  69
  70         *actual = (uint64_t)ret;
  71         return(True);
  72 }
  73
  74 static BOOL fd_write_func(void * handle,
  75                         uint8_t * buf,
  76                         uint64_t wanted,
  77                         uint64_t * actual)
  78 {
  79         ssize_t ret;
  80
  81         ret = write(IO_HANDLE_TO_FD(handle), buf, wanted);
  82         if (ret < 0) {
  83                 fprintf(stderr, "%s: %llu byte write failed: %s\n",
  84                                 PROGNAME, (unsigned long long)wanted,
  85                                 strerror(errno));
  86                 return(False);
  87         }
  88
  89         *actual = (uint64_t)ret;
  90         return(True);
  91 }
  92
  93 static struct dd_iohandle * open_fd_handle(const char * path,
  94                                         uint64_t io_size,
  95                                         int options)
  96 {
  97         struct fd_handle * fdh;
  98         int oflags = 0;
  99
 100         DEBUG(4, ("opening fd stream for %s\n", path));
 101         if ((fdh = talloc_zero(NULL, struct fd_handle)) == NULL) {
 102                 return(NULL);
 103         }
 104
 105         fdh->h.io_read = fd_read_func;
 106         fdh->h.io_write = fd_write_func;
 107         fdh->h.io_seek = fd_seek_func;
 108
 109         if (options & DD_DIRECT_IO) {
 110 #ifdef HAVE_OPEN_O_DIRECT
 111                 oflags |= O_DIRECT;
 112 #else
 113                 DEBUG(1, ("no support for direct IO on this platform\n"));
 114 #endif
 115         }
 116
 117         if (options & DD_SYNC_IO)
 118                 oflags |= O_SYNC;
 119
 120         oflags |= (options & DD_WRITE) ?  (O_WRONLY | O_CREAT) : (O_RDONLY);
 121
 122         fdh->fd = open(path, oflags, 0644);
 123         if (fdh->fd < 0) {
 124                 fprintf(stderr, "%s: %s: %s\n",
 125                         PROGNAME, path, strerror(errno));
 126                 talloc_free(fdh);
 127                 return(NULL);
 128         }
 129
 130         if (options & DD_OPLOCK) {
 131                 DEBUG(2, ("FIXME: take local oplock on %s\n", path));
 132         }
 133
 134         SMB_ASSERT((void *)fdh == (void *)&fdh->h);
 135         return(&fdh->h);
 136 }
 137
 138 /* ------------------------------------------------------------------------- */
 139 /* CIFS client IO.                                                           */
 140 /* ------------------------------------------------------------------------- */
 141
 142 struct cifs_handle
 143 {
 144         struct dd_iohandle      h;
 145         struct smbcli_state *   cli;
 146         int                     fnum;
 147         uint64_t                offset;
 148 };
 149
 150 #define IO_HANDLE_TO_SMB(h) ((struct cifs_handle *)(h))
 151
 152 BOOL smb_seek_func(void * handle, uint64_t offset)
 153 {
 154         IO_HANDLE_TO_SMB(handle)->offset = offset;
 155         return(True);
 156 }
 157
 158 BOOL smb_read_func(void * handle,
 159                 uint8_t * buf,
 160                 uint64_t wanted,
 161                 uint64_t * actual)
 162 {
 163         NTSTATUS                ret;
 164         union smb_read          r;
 165         struct cifs_handle *    smbh;
 166
 167         ZERO_STRUCT(r);
 168         smbh = IO_HANDLE_TO_SMB(handle);
 169
 170         r.generic.level         = RAW_READ_READX;
 171         r.readx.in.file.fnum    = smbh->fnum;
 172         r.readx.in.offset       = smbh->offset;
 173         r.readx.in.mincnt       = wanted;
 174         r.readx.in.maxcnt       = wanted;
 175         r.readx.out.data        = buf;
 176
 177         /* FIXME: Should I really set readx.in.remaining? That just seems
 178          * redundant.
 179          */
 180         ret = smb_raw_read(smbh->cli->tree, &r);
 181         if (!NT_STATUS_IS_OK(ret)) {
 182                 fprintf(stderr, "%s: %llu byte read failed: %s\n",
 183                                 PROGNAME, (unsigned long long)wanted,
 184                                 nt_errstr(ret));
 185                 return(False);
 186         }
 187
 188         /* Trap integer wrap. */
 189         SMB_ASSERT((smbh->offset + r.readx.out.nread) >= smbh->offset);
 190
 191         *actual = r.readx.out.nread;
 192         smbh->offset += r.readx.out.nread;
 193         return(True);
 194 }
 195
 196 BOOL smb_write_func(void * handle,
 197                 uint8_t * buf,
 198                 uint64_t wanted,
 199                 uint64_t * actual)
 200 {
 201         NTSTATUS                ret;
 202         union smb_write         w;
 203         struct cifs_handle *    smbh;
 204
 205         ZERO_STRUCT(w);
 206         smbh = IO_HANDLE_TO_SMB(handle);
 207
 208         w.generic.level         = RAW_WRITE_WRITEX;
 209         w.writex.in.file.fnum   = smbh->fnum;
 210         w.writex.in.offset      = smbh->offset;
 211         w.writex.in.count       = wanted;
 212         w.writex.in.data        = buf;
 213
 214         ret = smb_raw_write(smbh->cli->tree, &w);
 215         if (!NT_STATUS_IS_OK(ret)) {
 216                 fprintf(stderr, "%s: %llu byte write failed: %s\n",
 217                                 PROGNAME, (unsigned long long)wanted,
 218                                 nt_errstr(ret));
 219                 return(False);
 220         }
 221
 222         *actual = w.writex.out.nwritten;
 223         smbh->offset += w.writex.out.nwritten;
 224         return(True);
 225 }
 226
 227 static struct smbcli_state * init_smb_session(const char * host,
 228                                                 const char * share)
 229 {
 230         NTSTATUS                ret;
 231         struct smbcli_state *   cli = NULL;
 232
 233         /* When we support SMB URLs, we can get different user credentials for
 234          * each connection, but for now, we just use the same one for both.
 235          */
 236         ret = smbcli_full_connection(NULL, &cli, host, share,
 237                          NULL /* devtype */, cmdline_credentials, NULL /* events */);
 238
 239         if (!NT_STATUS_IS_OK(ret)) {
 240                 fprintf(stderr, "%s: connecting to //%s/%s: %s\n",
 241                         PROGNAME, host, share, nt_errstr(ret));
 242                 return(NULL);
 243         }
 244
 245         return(cli);
 246 }
 247
 248 static int open_smb_file(struct smbcli_state * cli,
 249                         const char * path,
 250                         int options)
 251 {
 252         NTSTATUS        ret;
 253         union smb_open  o;
 254
 255         ZERO_STRUCT(o);
 256
 257         o.ntcreatex.level = RAW_OPEN_NTCREATEX;
 258         o.ntcreatex.in.fname = path;
 259
 260         /* TODO: It's not clear whether to use these flags or to use the
 261          * similarly named NTCREATEX flags in the create_options field.
 262          */
 263         if (options & DD_DIRECT_IO)
 264                 o.ntcreatex.in.flags |= FILE_FLAG_NO_BUFFERING;
 265
 266         if (options & DD_SYNC_IO)
 267                 o.ntcreatex.in.flags |= FILE_FLAG_WRITE_THROUGH;
 268
 269         o.ntcreatex.in.access_mask |=
 270                 (options & DD_WRITE) ? SEC_FILE_WRITE_DATA
 271                                         : SEC_FILE_READ_DATA;
 272
 273         /* Try to create the file only if we will be writing to it. */
 274         o.ntcreatex.in.open_disposition =
 275                 (options & DD_WRITE) ? NTCREATEX_DISP_OPEN_IF
 276                                         : NTCREATEX_DISP_OPEN;
 277
 278         o.ntcreatex.in.share_access =
 279                 NTCREATEX_SHARE_ACCESS_READ | NTCREATEX_SHARE_ACCESS_WRITE;
 280
 281         if (options & DD_OPLOCK) {
 282                 o.ntcreatex.in.flags |= NTCREATEX_FLAGS_REQUEST_OPLOCK;
 283         }
 284
 285         ret = smb_raw_open(cli->tree, NULL, &o);
 286         if (!NT_STATUS_IS_OK(ret)) {
 287                 fprintf(stderr, "%s: opening %s: %s\n",
 288                         PROGNAME, path, nt_errstr(ret));
 289                 return(-1);
 290         }
 291
 292         return(o.ntcreatex.out.file.fnum);
 293 }
 294
 295 static struct dd_iohandle * open_cifs_handle(const char * host,
 296                                         const char * share,
 297                                         const char * path,
 298                                         uint64_t io_size,
 299                                         int options)
 300 {
 301         struct cifs_handle * smbh;
 302
 303         if (path == NULL  || *path == '\0') {
 304                 fprintf(stderr, "%s: missing path name within share //%s/%s\n",
 305                         PROGNAME, host, share);
 306         }
 307
 308         DEBUG(4, ("opening SMB stream to //%s/%s for %s\n",
 309                 host, share, path));
 310
 311         if ((smbh = talloc_zero(NULL, struct cifs_handle)) == NULL) {
 312                 return(NULL);
 313         }
 314
 315         smbh->h.io_read = smb_read_func;
 316         smbh->h.io_write = smb_write_func;
 317         smbh->h.io_seek = smb_seek_func;
 318
 319         if ((smbh->cli = init_smb_session(host, share)) == NULL) {
 320                 return(NULL);
 321         }
 322
 323         DEBUG(4, ("connected to //%s/%s with xmit size of %u bytes\n",
 324                 host, share, smbh->cli->transport->negotiate.max_xmit));
 325
 326         smbh->fnum = open_smb_file(smbh->cli, path, options);
 327         return(&smbh->h);
 328 }
 329
 330 /* ------------------------------------------------------------------------- */
 331 /* Abstract IO interface.                                                    */
 332 /* ------------------------------------------------------------------------- */
 333
 334 struct dd_iohandle * dd_open_path(const char * path,
 335                                 uint64_t io_size,
 336                                 int options)
 337 {
 338         if (file_exist(path)) {
 339                 return(open_fd_handle(path, io_size, options));
 340         } else {
 341                 char * host;
 342                 char * share;
 343
 344                 if (smbcli_parse_unc(path, NULL, &host, &share)) {
 345                         const char * remain;
 346                         remain = strstr(path, share) + strlen(share);
 347
 348                         /* Skip over leading directory separators. */
 349                         while (*remain == '/' || *remain == '\\') { remain++; }
 350
 351                         return(open_cifs_handle(host, share, remain,
 352                                                 io_size, options));
 353                 }
 354
 355                 return(open_fd_handle(path, io_size, options));
 356         }
 357 }
 358
 359 /* Fill the buffer till it has at least need_size bytes. Use read operations of
 360  * block_size bytes. Return the number of bytes read and fill buf_size with
 361  * the new buffer size.
 362  *
 363  * NOTE: The IO buffer is guaranteed to be big enough to fit
 364  * need_size + block_size bytes into it.
 365  */
 366 BOOL dd_fill_block(struct dd_iohandle * h,
 367                 uint8_t * buf,
 368                 uint64_t * buf_size,
 369                 uint64_t need_size,
 370                 uint64_t block_size)
 371 {
 372         uint64_t read_size;
 373
 374         SMB_ASSERT(block_size > 0);
 375         SMB_ASSERT(need_size > 0);
 376
 377         while (*buf_size < need_size) {
 378
 379                 if (!h->io_read(h, buf + (*buf_size), block_size, &read_size)) {
 380                         return(False);
 381                 }
 382
 383                 if (read_size == 0) {
 384                         h->io_flags |= DD_END_OF_FILE;
 385                         break;
 386                 }
 387
 388                 DEBUG(6, ("added %llu bytes to IO buffer (need %llu bytes)\n",
 389                         (unsigned long long)read_size,
 390                         (unsigned long long)need_size));
 391
 392                 *buf_size += read_size;
 393                 dd_stats.in.bytes += read_size;
 394
 395                 if (read_size == block_size) {
 396                         dd_stats.in.fblocks++;
 397                 } else {
 398                         DEBUG(3, ("partial read of %llu bytes (expected %llu)\n",
 399                                 (unsigned long long)read_size,
 400                                 (unsigned long long)block_size));
 401                         dd_stats.in.pblocks++;
 402                 }
 403         }
 404
 405         return(True);
 406 }
 407
 408 /* Flush a buffer that contains buf_size bytes. Use writes of block_size to do it,
 409  * and shift any remaining bytes back to the head of the buffer when there are
 410  * no more block_size sized IOs left.
 411  */
 412 BOOL dd_flush_block(struct dd_iohandle * h,
 413                 uint8_t * buf,
 414                 uint64_t * buf_size,
 415                 uint64_t block_size)
 416 {
 417         uint64_t write_size;
 418         uint64_t total_size = 0;
 419
 420         SMB_ASSERT(block_size > 0);
 421
 422         /* We have explicitly been asked to write a partial block. */
 423         if ((*buf_size) < block_size) {
 424
 425                 if (!h->io_write(h, buf, *buf_size, &write_size)) {
 426                         return(False);
 427                 }
 428
 429                 if (write_size == 0) {
 430                         fprintf(stderr, "%s: unexpectedly wrote 0 bytes\n",
 431                                         PROGNAME);
 432                         return(False);
 433                 }
 434
 435                 total_size += write_size;
 436                 dd_stats.out.bytes += write_size;
 437                 dd_stats.out.pblocks++;
 438         }
 439
 440         /* Write as many full blocks as there are in the buffer. */
 441         while (((*buf_size) - total_size) >= block_size) {
 442
 443                 if (!h->io_write(h, buf + total_size, block_size, &write_size)) {
 444                         return(False);
 445                 }
 446
 447                 if (write_size == 0) {
 448                         fprintf(stderr, "%s: unexpectedly wrote 0 bytes\n",
 449                                         PROGNAME);
 450                         return(False);
 451                 }
 452
 453                 if (write_size == block_size) {
 454                         dd_stats.out.fblocks++;
 455                 } else {
 456                         dd_stats.out.pblocks++;
 457                 }
 458
 459                 total_size += write_size;
 460                 dd_stats.out.bytes += write_size;
 461
 462                 DEBUG(6, ("flushed %llu bytes from IO buffer of %llu bytes (%llu remain)\n",
 463                         (unsigned long long)block_size,
 464                         (unsigned long long)block_size,
 465                         (unsigned long long)(block_size - total_size)));
 466         }
 467
 468         SMB_ASSERT(total_size > 0);
 469
 470         /* We have flushed as much of the IO buffer as we can while
 471          * still doing block_size'd operations. Shift any remaining data
 472          * to the front of the IO buffer.
 473          */
 474         if ((*buf_size) > total_size) {
 475                 uint64_t remain = (*buf_size) - total_size;
 476
 477                 DEBUG(3, ("shifting %llu remainder bytes to IO buffer head\n",
 478                         (unsigned long long)remain));
 479
 480                 memmove(buf, buf + total_size, remain);
 481                 (*buf_size) = remain;
 482         } else if ((*buf_size) == total_size) {
 483                 (*buf_size) = 0;
 484         } else {
 485                 /* Else buffer contains buf_size bytes that we will append
 486                  * to next time round.
 487                  */
 488                 DEBUG(3, ("%llu unflushed bytes left in IO buffer\n",
 489                         (unsigned long long)(*buf_size)));
 490         }
 491
 492         return(True);
 493 }
 494
 495 /* vim: set sw=8 sts=8 ts=8 tw=79 : */