source/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 static bool smb_seek_func(void * handle, uint64_t offset)
 153 {
 154         IO_HANDLE_TO_SMB(handle)->offset = offset;
 155         return(true);
 156 }
 157
 158 static bool smb_read_func(void * handle, uint8_t * buf, uint64_t wanted,
 159                           uint64_t * actual)
 160 {
 161         NTSTATUS                ret;
 162         union smb_read          r;
 163         struct cifs_handle *    smbh;
 164
 165         ZERO_STRUCT(r);
 166         smbh = IO_HANDLE_TO_SMB(handle);
 167
 168         r.generic.level         = RAW_READ_READX;
 169         r.readx.in.file.fnum    = smbh->fnum;
 170         r.readx.in.offset       = smbh->offset;
 171         r.readx.in.mincnt       = wanted;
 172         r.readx.in.maxcnt       = wanted;
 173         r.readx.out.data        = buf;
 174
 175         /* FIXME: Should I really set readx.in.remaining? That just seems
 176          * redundant.
 177          */
 178         ret = smb_raw_read(smbh->cli->tree, &r);
 179         if (!NT_STATUS_IS_OK(ret)) {
 180                 fprintf(stderr, "%s: %llu byte read failed: %s\n",
 181                                 PROGNAME, (unsigned long long)wanted,
 182                                 nt_errstr(ret));
 183                 return(false);
 184         }
 185
 186         /* Trap integer wrap. */
 187         SMB_ASSERT((smbh->offset + r.readx.out.nread) >= smbh->offset);
 188
 189         *actual = r.readx.out.nread;
 190         smbh->offset += r.readx.out.nread;
 191         return(true);
 192 }
 193
 194 static bool smb_write_func(void * handle, uint8_t * buf, uint64_t wanted,
 195                            uint64_t * actual)
 196 {
 197         NTSTATUS                ret;
 198         union smb_write         w;
 199         struct cifs_handle *    smbh;
 200
 201         ZERO_STRUCT(w);
 202         smbh = IO_HANDLE_TO_SMB(handle);
 203
 204         w.generic.level         = RAW_WRITE_WRITEX;
 205         w.writex.in.file.fnum   = smbh->fnum;
 206         w.writex.in.offset      = smbh->offset;
 207         w.writex.in.count       = wanted;
 208         w.writex.in.data        = buf;
 209
 210         ret = smb_raw_write(smbh->cli->tree, &w);
 211         if (!NT_STATUS_IS_OK(ret)) {
 212                 fprintf(stderr, "%s: %llu byte write failed: %s\n",
 213                                 PROGNAME, (unsigned long long)wanted,
 214                                 nt_errstr(ret));
 215                 return(false);
 216         }
 217
 218         *actual = w.writex.out.nwritten;
 219         smbh->offset += w.writex.out.nwritten;
 220         return(true);
 221 }
 222
 223 static struct smbcli_state * init_smb_session(const char * host,
 224                                                 const char * share)
 225 {
 226         NTSTATUS                ret;
 227         struct smbcli_state *   cli = NULL;
 228
 229         /* When we support SMB URLs, we can get different user credentials for
 230          * each connection, but for now, we just use the same one for both.
 231          */
 232         ret = smbcli_full_connection(NULL, &cli, host, share,
 233                          NULL /* devtype */, cmdline_credentials, NULL /* events */);
 234
 235         if (!NT_STATUS_IS_OK(ret)) {
 236                 fprintf(stderr, "%s: connecting to //%s/%s: %s\n",
 237                         PROGNAME, host, share, nt_errstr(ret));
 238                 return(NULL);
 239         }
 240
 241         return(cli);
 242 }
 243
 244 static int open_smb_file(struct smbcli_state * cli,
 245                         const char * path,
 246                         int options)
 247 {
 248         NTSTATUS        ret;
 249         union smb_open  o;
 250
 251         ZERO_STRUCT(o);
 252
 253         o.ntcreatex.level = RAW_OPEN_NTCREATEX;
 254         o.ntcreatex.in.fname = path;
 255
 256         /* TODO: It's not clear whether to use these flags or to use the
 257          * similarly named NTCREATEX flags in the create_options field.
 258          */
 259         if (options & DD_DIRECT_IO)
 260                 o.ntcreatex.in.flags |= FILE_FLAG_NO_BUFFERING;
 261
 262         if (options & DD_SYNC_IO)
 263                 o.ntcreatex.in.flags |= FILE_FLAG_WRITE_THROUGH;
 264
 265         o.ntcreatex.in.access_mask |=
 266                 (options & DD_WRITE) ? SEC_FILE_WRITE_DATA
 267                                         : SEC_FILE_READ_DATA;
 268
 269         /* Try to create the file only if we will be writing to it. */
 270         o.ntcreatex.in.open_disposition =
 271                 (options & DD_WRITE) ? NTCREATEX_DISP_OPEN_IF
 272                                         : NTCREATEX_DISP_OPEN;
 273
 274         o.ntcreatex.in.share_access =
 275                 NTCREATEX_SHARE_ACCESS_READ | NTCREATEX_SHARE_ACCESS_WRITE;
 276
 277         if (options & DD_OPLOCK) {
 278                 o.ntcreatex.in.flags |= NTCREATEX_FLAGS_REQUEST_OPLOCK;
 279         }
 280
 281         ret = smb_raw_open(cli->tree, NULL, &o);
 282         if (!NT_STATUS_IS_OK(ret)) {
 283                 fprintf(stderr, "%s: opening %s: %s\n",
 284                         PROGNAME, path, nt_errstr(ret));
 285                 return(-1);
 286         }
 287
 288         return(o.ntcreatex.out.file.fnum);
 289 }
 290
 291 static struct dd_iohandle * open_cifs_handle(const char * host,
 292                                         const char * share,
 293                                         const char * path,
 294                                         uint64_t io_size,
 295                                         int options)
 296 {
 297         struct cifs_handle * smbh;
 298
 299         if (path == NULL  || *path == '\0') {
 300                 fprintf(stderr, "%s: missing path name within share //%s/%s\n",
 301                         PROGNAME, host, share);
 302         }
 303
 304         DEBUG(4, ("opening SMB stream to //%s/%s for %s\n",
 305                 host, share, path));
 306
 307         if ((smbh = talloc_zero(NULL, struct cifs_handle)) == NULL) {
 308                 return(NULL);
 309         }
 310
 311         smbh->h.io_read = smb_read_func;
 312         smbh->h.io_write = smb_write_func;
 313         smbh->h.io_seek = smb_seek_func;
 314
 315         if ((smbh->cli = init_smb_session(host, share)) == NULL) {
 316                 return(NULL);
 317         }
 318
 319         DEBUG(4, ("connected to //%s/%s with xmit size of %u bytes\n",
 320                 host, share, smbh->cli->transport->negotiate.max_xmit));
 321
 322         smbh->fnum = open_smb_file(smbh->cli, path, options);
 323         return(&smbh->h);
 324 }
 325
 326 /* ------------------------------------------------------------------------- */
 327 /* Abstract IO interface.                                                    */
 328 /* ------------------------------------------------------------------------- */
 329
 330 struct dd_iohandle * dd_open_path(const char * path,
 331                                 uint64_t io_size,
 332                                 int options)
 333 {
 334         if (file_exist(path)) {
 335                 return(open_fd_handle(path, io_size, options));
 336         } else {
 337                 char * host;
 338                 char * share;
 339
 340                 if (smbcli_parse_unc(path, NULL, &host, &share)) {
 341                         const char * remain;
 342                         remain = strstr(path, share) + strlen(share);
 343
 344                         /* Skip over leading directory separators. */
 345                         while (*remain == '/' || *remain == '\\') { remain++; }
 346
 347                         return(open_cifs_handle(host, share, remain,
 348                                                 io_size, options));
 349                 }
 350
 351                 return(open_fd_handle(path, io_size, options));
 352         }
 353 }
 354
 355 /* Fill the buffer till it has at least need_size bytes. Use read operations of
 356  * block_size bytes. Return the number of bytes read and fill buf_size with
 357  * the new buffer size.
 358  *
 359  * NOTE: The IO buffer is guaranteed to be big enough to fit
 360  * need_size + block_size bytes into it.
 361  */
 362 bool dd_fill_block(struct dd_iohandle * h,
 363                 uint8_t * buf,
 364                 uint64_t * buf_size,
 365                 uint64_t need_size,
 366                 uint64_t block_size)
 367 {
 368         uint64_t read_size;
 369
 370         SMB_ASSERT(block_size > 0);
 371         SMB_ASSERT(need_size > 0);
 372
 373         while (*buf_size < need_size) {
 374
 375                 if (!h->io_read(h, buf + (*buf_size), block_size, &read_size)) {
 376                         return(false);
 377                 }
 378
 379                 if (read_size == 0) {
 380                         h->io_flags |= DD_END_OF_FILE;
 381                         break;
 382                 }
 383
 384                 DEBUG(6, ("added %llu bytes to IO buffer (need %llu bytes)\n",
 385                         (unsigned long long)read_size,
 386                         (unsigned long long)need_size));
 387
 388                 *buf_size += read_size;
 389                 dd_stats.in.bytes += read_size;
 390
 391                 if (read_size == block_size) {
 392                         dd_stats.in.fblocks++;
 393                 } else {
 394                         DEBUG(3, ("partial read of %llu bytes (expected %llu)\n",
 395                                 (unsigned long long)read_size,
 396                                 (unsigned long long)block_size));
 397                         dd_stats.in.pblocks++;
 398                 }
 399         }
 400
 401         return(true);
 402 }
 403
 404 /* Flush a buffer that contains buf_size bytes. Use writes of block_size to do it,
 405  * and shift any remaining bytes back to the head of the buffer when there are
 406  * no more block_size sized IOs left.
 407  */
 408 bool dd_flush_block(struct dd_iohandle * h,
 409                 uint8_t * buf,
 410                 uint64_t * buf_size,
 411                 uint64_t block_size)
 412 {
 413         uint64_t write_size;
 414         uint64_t total_size = 0;
 415
 416         SMB_ASSERT(block_size > 0);
 417
 418         /* We have explicitly been asked to write a partial block. */
 419         if ((*buf_size) < block_size) {
 420
 421                 if (!h->io_write(h, buf, *buf_size, &write_size)) {
 422                         return(false);
 423                 }
 424
 425                 if (write_size == 0) {
 426                         fprintf(stderr, "%s: unexpectedly wrote 0 bytes\n",
 427                                         PROGNAME);
 428                         return(false);
 429                 }
 430
 431                 total_size += write_size;
 432                 dd_stats.out.bytes += write_size;
 433                 dd_stats.out.pblocks++;
 434         }
 435
 436         /* Write as many full blocks as there are in the buffer. */
 437         while (((*buf_size) - total_size) >= block_size) {
 438
 439                 if (!h->io_write(h, buf + total_size, block_size, &write_size)) {
 440                         return(false);
 441                 }
 442
 443                 if (write_size == 0) {
 444                         fprintf(stderr, "%s: unexpectedly wrote 0 bytes\n",
 445                                         PROGNAME);
 446                         return(false);
 447                 }
 448
 449                 if (write_size == block_size) {
 450                         dd_stats.out.fblocks++;
 451                 } else {
 452                         dd_stats.out.pblocks++;
 453                 }
 454
 455                 total_size += write_size;
 456                 dd_stats.out.bytes += write_size;
 457
 458                 DEBUG(6, ("flushed %llu bytes from IO buffer of %llu bytes (%llu remain)\n",
 459                         (unsigned long long)block_size,
 460                         (unsigned long long)block_size,
 461                         (unsigned long long)(block_size - total_size)));
 462         }
 463
 464         SMB_ASSERT(total_size > 0);
 465
 466         /* We have flushed as much of the IO buffer as we can while
 467          * still doing block_size'd operations. Shift any remaining data
 468          * to the front of the IO buffer.
 469          */
 470         if ((*buf_size) > total_size) {
 471                 uint64_t remain = (*buf_size) - total_size;
 472
 473                 DEBUG(3, ("shifting %llu remainder bytes to IO buffer head\n",
 474                         (unsigned long long)remain));
 475
 476                 memmove(buf, buf + total_size, remain);
 477                 (*buf_size) = remain;
 478         } else if ((*buf_size) == total_size) {
 479                 (*buf_size) = 0;
 480         } else {
 481                 /* Else buffer contains buf_size bytes that we will append
 482                  * to next time round.
 483                  */
 484                 DEBUG(3, ("%llu unflushed bytes left in IO buffer\n",
 485                         (unsigned long long)(*buf_size)));
 486         }
 487
 488         return(true);
 489 }
 490
 491 /* vim: set sw=8 sts=8 ts=8 tw=79 : */