source3/smbd/vfs.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    VFS initialisation and support functions
   5    Copyright (C) Tim Potter 1999
   6    Copyright (C) Alexander Bokovoy 2002
   7    Copyright (C) James Peach 2006
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21
  22    This work was sponsored by Optifacio Software Services, Inc.
  23 */
  24
  25 #include "includes.h"
  26 #include "smbd/globals.h"
  27
  28 #undef DBGC_CLASS
  29 #define DBGC_CLASS DBGC_VFS
  30
  31 static_decl_vfs;
  32
  33 struct vfs_init_function_entry {
  34         char *name;
  35         const vfs_op_tuple *vfs_op_tuples;
  36         struct vfs_init_function_entry *prev, *next;
  37 };
  38
  39 /****************************************************************************
  40     maintain the list of available backends
  41 ****************************************************************************/
  42
  43 static struct vfs_init_function_entry *vfs_find_backend_entry(const char *name)
  44 {
  45         struct vfs_init_function_entry *entry = backends;
  46
  47         DEBUG(10, ("vfs_find_backend_entry called for %s\n", name));
  48
  49         while(entry) {
  50                 if (strcmp(entry->name, name)==0) return entry;
  51                 entry = entry->next;
  52         }
  53
  54         return NULL;
  55 }
  56
  57 NTSTATUS smb_register_vfs(int version, const char *name, const vfs_op_tuple *vfs_op_tuples)
  58 {
  59         struct vfs_init_function_entry *entry = backends;
  60
  61         if ((version != SMB_VFS_INTERFACE_VERSION)) {
  62                 DEBUG(0, ("Failed to register vfs module.\n"
  63                           "The module was compiled against SMB_VFS_INTERFACE_VERSION %d,\n"
  64                           "current SMB_VFS_INTERFACE_VERSION is %d.\n"
  65                           "Please recompile against the current Samba Version!\n",
  66                           version, SMB_VFS_INTERFACE_VERSION));
  67                 return NT_STATUS_OBJECT_TYPE_MISMATCH;
  68         }
  69
  70         if (!name || !name[0] || !vfs_op_tuples) {
  71                 DEBUG(0,("smb_register_vfs() called with NULL pointer or empty name!\n"));
  72                 return NT_STATUS_INVALID_PARAMETER;
  73         }
  74
  75         if (vfs_find_backend_entry(name)) {
  76                 DEBUG(0,("VFS module %s already loaded!\n", name));
  77                 return NT_STATUS_OBJECT_NAME_COLLISION;
  78         }
  79
  80         entry = SMB_XMALLOC_P(struct vfs_init_function_entry);
  81         entry->name = smb_xstrdup(name);
  82         entry->vfs_op_tuples = vfs_op_tuples;
  83
  84         DLIST_ADD(backends, entry);
  85         DEBUG(5, ("Successfully added vfs backend '%s'\n", name));
  86         return NT_STATUS_OK;
  87 }
  88
  89 /****************************************************************************
  90   initialise default vfs hooks
  91 ****************************************************************************/
  92
  93 static void vfs_init_default(connection_struct *conn)
  94 {
  95         DEBUG(3, ("Initialising default vfs hooks\n"));
  96         vfs_init_custom(conn, DEFAULT_VFS_MODULE_NAME);
  97 }
  98
  99 /****************************************************************************
 100   initialise custom vfs hooks
 101  ****************************************************************************/
 102
 103 static inline void vfs_set_operation(struct vfs_ops * vfs, vfs_op_type which,
 104                                 struct vfs_handle_struct * handle, void * op)
 105 {
 106         ((struct vfs_handle_struct **)&vfs->handles)[which] = handle;
 107         ((void **)(void *)&vfs->ops)[which] = op;
 108 }
 109
 110 bool vfs_init_custom(connection_struct *conn, const char *vfs_object)
 111 {
 112         const vfs_op_tuple *ops;
 113         char *module_path = NULL;
 114         char *module_name = NULL;
 115         char *module_param = NULL, *p;
 116         int i;
 117         vfs_handle_struct *handle;
 118         const struct vfs_init_function_entry *entry;
 119
 120         if (!conn||!vfs_object||!vfs_object[0]) {
 121                 DEBUG(0,("vfs_init_custon() called with NULL pointer or emtpy vfs_object!\n"));
 122                 return False;
 123         }
 124
 125         if(!backends) {
 126                 static_init_vfs;
 127         }
 128
 129         DEBUG(3, ("Initialising custom vfs hooks from [%s]\n", vfs_object));
 130
 131         module_path = smb_xstrdup(vfs_object);
 132
 133         p = strchr_m(module_path, ':');
 134
 135         if (p) {
 136                 *p = 0;
 137                 module_param = p+1;
 138                 trim_char(module_param, ' ', ' ');
 139         }
 140
 141         trim_char(module_path, ' ', ' ');
 142
 143         module_name = smb_xstrdup(module_path);
 144
 145         if ((module_name[0] == '/') &&
 146             (strcmp(module_path, DEFAULT_VFS_MODULE_NAME) != 0)) {
 147
 148                 /*
 149                  * Extract the module name from the path. Just use the base
 150                  * name of the last path component.
 151                  */
 152
 153                 SAFE_FREE(module_name);
 154                 module_name = smb_xstrdup(strrchr_m(module_path, '/')+1);
 155
 156                 p = strchr_m(module_name, '.');
 157
 158                 if (p != NULL) {
 159                         *p = '\0';
 160                 }
 161         }
 162
 163         /* First, try to load the module with the new module system */
 164         entry = vfs_find_backend_entry(module_name);
 165         if (!entry) {
 166                 NTSTATUS status;
 167
 168                 DEBUG(5, ("vfs module [%s] not loaded - trying to load...\n",
 169                           vfs_object));
 170
 171                 status = smb_probe_module("vfs", module_path);
 172                 if (!NT_STATUS_IS_OK(status)) {
 173                         DEBUG(0, ("error probing vfs module '%s': %s\n",
 174                                   module_path, nt_errstr(status)));
 175                         goto fail;
 176                 }
 177
 178                 entry = vfs_find_backend_entry(module_name);
 179                 if (!entry) {
 180                         DEBUG(0,("Can't find a vfs module [%s]\n",vfs_object));
 181                         goto fail;
 182                 }
 183         }
 184
 185         DEBUGADD(5,("Successfully loaded vfs module [%s] with the new modules system\n", vfs_object));
 186         if ((ops = entry->vfs_op_tuples) == NULL) {
 187                 DEBUG(0, ("entry->vfs_op_tuples==NULL for [%s] failed\n", vfs_object));
 188                 goto fail;
 189         }
 190
 191         handle = TALLOC_ZERO_P(conn, vfs_handle_struct);
 192         if (!handle) {
 193                 DEBUG(0,("TALLOC_ZERO() failed!\n"));
 194                 goto fail;
 195         }
 196         memcpy(&handle->vfs_next, &conn->vfs, sizeof(struct vfs_ops));
 197         handle->conn = conn;
 198         if (module_param) {
 199                 handle->param = talloc_strdup(conn, module_param);
 200         }
 201         DLIST_ADD(conn->vfs_handles, handle);
 202
 203         for(i=0; ops[i].op != NULL; i++) {
 204                 DEBUG(5, ("Checking operation #%d (type %d, layer %d)\n", i, ops[i].type, ops[i].layer));
 205                 if(ops[i].layer == SMB_VFS_LAYER_OPAQUE) {
 206                         /* If this operation was already made opaque by different module, it
 207                          * will be overridden here.
 208                          */
 209                         DEBUGADD(5, ("Making operation type %d opaque [module %s]\n", ops[i].type, vfs_object));
 210                         vfs_set_operation(&conn->vfs_opaque, ops[i].type, handle, ops[i].op);
 211                 }
 212                 /* Change current VFS disposition*/
 213                 DEBUGADD(5, ("Accepting operation type %d from module %s\n", ops[i].type, vfs_object));
 214                 vfs_set_operation(&conn->vfs, ops[i].type, handle, ops[i].op);
 215         }
 216
 217         SAFE_FREE(module_path);
 218         SAFE_FREE(module_name);
 219         return True;
 220
 221  fail:
 222         SAFE_FREE(module_path);
 223         SAFE_FREE(module_name);
 224         return False;
 225 }
 226
 227 /*****************************************************************
 228  Allow VFS modules to extend files_struct with VFS-specific state.
 229  This will be ok for small numbers of extensions, but might need to
 230  be refactored if it becomes more widely used.
 231 ******************************************************************/
 232
 233 #define EXT_DATA_AREA(e) ((uint8 *)(e) + sizeof(struct vfs_fsp_data))
 234
 235 void *vfs_add_fsp_extension_notype(vfs_handle_struct *handle,
 236                                    files_struct *fsp, size_t ext_size,
 237                                    void (*destroy_fn)(void *p_data))
 238 {
 239         struct vfs_fsp_data *ext;
 240         void * ext_data;
 241
 242         /* Prevent VFS modules adding multiple extensions. */
 243         if ((ext_data = vfs_fetch_fsp_extension(handle, fsp))) {
 244                 return ext_data;
 245         }
 246
 247         ext = (struct vfs_fsp_data *)TALLOC_ZERO(
 248                 handle->conn, sizeof(struct vfs_fsp_data) + ext_size);
 249         if (ext == NULL) {
 250                 return NULL;
 251         }
 252
 253         ext->owner = handle;
 254         ext->next = fsp->vfs_extension;
 255         ext->destroy = destroy_fn;
 256         fsp->vfs_extension = ext;
 257         return EXT_DATA_AREA(ext);
 258 }
 259
 260 void vfs_remove_fsp_extension(vfs_handle_struct *handle, files_struct *fsp)
 261 {
 262         struct vfs_fsp_data *curr;
 263         struct vfs_fsp_data *prev;
 264
 265         for (curr = fsp->vfs_extension, prev = NULL;
 266              curr;
 267              prev = curr, curr = curr->next) {
 268                 if (curr->owner == handle) {
 269                     if (prev) {
 270                             prev->next = curr->next;
 271                     } else {
 272                             fsp->vfs_extension = curr->next;
 273                     }
 274                     if (curr->destroy) {
 275                             curr->destroy(EXT_DATA_AREA(curr));
 276                     }
 277                     TALLOC_FREE(curr);
 278                     return;
 279                 }
 280         }
 281 }
 282
 283 void *vfs_memctx_fsp_extension(vfs_handle_struct *handle, files_struct *fsp)
 284 {
 285         struct vfs_fsp_data *head;
 286
 287         for (head = fsp->vfs_extension; head; head = head->next) {
 288                 if (head->owner == handle) {
 289                         return head;
 290                 }
 291         }
 292
 293         return NULL;
 294 }
 295
 296 void *vfs_fetch_fsp_extension(vfs_handle_struct *handle, files_struct *fsp)
 297 {
 298         struct vfs_fsp_data *head;
 299
 300         head = (struct vfs_fsp_data *)vfs_memctx_fsp_extension(handle, fsp);
 301         if (head != NULL) {
 302                 return EXT_DATA_AREA(head);
 303         }
 304
 305         return NULL;
 306 }
 307
 308 #undef EXT_DATA_AREA
 309
 310 /*****************************************************************
 311  Generic VFS init.
 312 ******************************************************************/
 313
 314 bool smbd_vfs_init(connection_struct *conn)
 315 {
 316         const char **vfs_objects;
 317         unsigned int i = 0;
 318         int j = 0;
 319
 320         /* Normal share - initialise with disk access functions */
 321         vfs_init_default(conn);
 322         vfs_objects = lp_vfs_objects(SNUM(conn));
 323
 324         /* Override VFS functions if 'vfs object' was not specified*/
 325         if (!vfs_objects || !vfs_objects[0])
 326                 return True;
 327
 328         for (i=0; vfs_objects[i] ;) {
 329                 i++;
 330         }
 331
 332         for (j=i-1; j >= 0; j--) {
 333                 if (!vfs_init_custom(conn, vfs_objects[j])) {
 334                         DEBUG(0, ("smbd_vfs_init: vfs_init_custom failed for %s\n", vfs_objects[j]));
 335                         return False;
 336                 }
 337         }
 338         return True;
 339 }
 340
 341 /*******************************************************************
 342  Check if directory exists.
 343 ********************************************************************/
 344
 345 bool vfs_directory_exist(connection_struct *conn, const char *dname, SMB_STRUCT_STAT *st)
 346 {
 347         SMB_STRUCT_STAT st2;
 348         bool ret;
 349
 350         if (!st)
 351                 st = &st2;
 352
 353         if (SMB_VFS_STAT(conn,dname,st) != 0)
 354                 return(False);
 355
 356         ret = S_ISDIR(st->st_ex_mode);
 357         if(!ret)
 358                 errno = ENOTDIR;
 359
 360         return ret;
 361 }
 362
 363 /*******************************************************************
 364  Check if an object exists in the vfs.
 365 ********************************************************************/
 366
 367 bool vfs_object_exist(connection_struct *conn,const char *fname,SMB_STRUCT_STAT *sbuf)
 368 {
 369         SMB_STRUCT_STAT st;
 370
 371         if (!sbuf)
 372                 sbuf = &st;
 373
 374         ZERO_STRUCTP(sbuf);
 375
 376         if (SMB_VFS_STAT(conn,fname,sbuf) == -1)
 377                 return(False);
 378         return True;
 379 }
 380
 381 /*******************************************************************
 382  Check if a file exists in the vfs.
 383 ********************************************************************/
 384
 385 NTSTATUS vfs_file_exist(connection_struct *conn, struct smb_filename *smb_fname)
 386 {
 387         char *fname = NULL;
 388         NTSTATUS status;
 389
 390         status = get_full_smb_filename(talloc_tos(), smb_fname, &fname);
 391         if (!NT_STATUS_IS_OK(status)) {
 392                 goto out;
 393         }
 394
 395         status = NT_STATUS_OBJECT_NAME_NOT_FOUND;
 396         if (SMB_VFS_STAT(conn, fname, &smb_fname->st) == -1) {
 397                 goto out;
 398         }
 399
 400         /* Only return OK if stat was successful and S_ISREG */
 401         if (S_ISREG(smb_fname->st.st_ex_mode)) {
 402                 status = NT_STATUS_OK;
 403         }
 404  out:
 405         TALLOC_FREE(fname);
 406         return status;
 407 }
 408
 409 /****************************************************************************
 410  Read data from fsp on the vfs. (note: EINTR re-read differs from vfs_write_data)
 411 ****************************************************************************/
 412
 413 ssize_t vfs_read_data(files_struct *fsp, char *buf, size_t byte_count)
 414 {
 415         size_t total=0;
 416
 417         while (total < byte_count)
 418         {
 419                 ssize_t ret = SMB_VFS_READ(fsp, buf + total,
 420                                            byte_count - total);
 421
 422                 if (ret == 0) return total;
 423                 if (ret == -1) {
 424                         if (errno == EINTR)
 425                                 continue;
 426                         else
 427                                 return -1;
 428                 }
 429                 total += ret;
 430         }
 431         return (ssize_t)total;
 432 }
 433
 434 ssize_t vfs_pread_data(files_struct *fsp, char *buf,
 435                 size_t byte_count, SMB_OFF_T offset)
 436 {
 437         size_t total=0;
 438
 439         while (total < byte_count)
 440         {
 441                 ssize_t ret = SMB_VFS_PREAD(fsp, buf + total,
 442                                         byte_count - total, offset + total);
 443
 444                 if (ret == 0) return total;
 445                 if (ret == -1) {
 446                         if (errno == EINTR)
 447                                 continue;
 448                         else
 449                                 return -1;
 450                 }
 451                 total += ret;
 452         }
 453         return (ssize_t)total;
 454 }
 455
 456 /****************************************************************************
 457  Write data to a fd on the vfs.
 458 ****************************************************************************/
 459
 460 ssize_t vfs_write_data(struct smb_request *req,
 461                         files_struct *fsp,
 462                         const char *buffer,
 463                         size_t N)
 464 {
 465         size_t total=0;
 466         ssize_t ret;
 467
 468         if (req && req->unread_bytes) {
 469                 SMB_ASSERT(req->unread_bytes == N);
 470                 /* VFS_RECVFILE must drain the socket
 471                  * before returning. */
 472                 req->unread_bytes = 0;
 473                 return SMB_VFS_RECVFILE(smbd_server_fd(),
 474                                         fsp,
 475                                         (SMB_OFF_T)-1,
 476                                         N);
 477         }
 478
 479         while (total < N) {
 480                 ret = SMB_VFS_WRITE(fsp, buffer + total, N - total);
 481
 482                 if (ret == -1)
 483                         return -1;
 484                 if (ret == 0)
 485                         return total;
 486
 487                 total += ret;
 488         }
 489         return (ssize_t)total;
 490 }
 491
 492 ssize_t vfs_pwrite_data(struct smb_request *req,
 493                         files_struct *fsp,
 494                         const char *buffer,
 495                         size_t N,
 496                         SMB_OFF_T offset)
 497 {
 498         size_t total=0;
 499         ssize_t ret;
 500
 501         if (req && req->unread_bytes) {
 502                 SMB_ASSERT(req->unread_bytes == N);
 503                 /* VFS_RECVFILE must drain the socket
 504                  * before returning. */
 505                 req->unread_bytes = 0;
 506                 return SMB_VFS_RECVFILE(smbd_server_fd(),
 507                                         fsp,
 508                                         offset,
 509                                         N);
 510         }
 511
 512         while (total < N) {
 513                 ret = SMB_VFS_PWRITE(fsp, buffer + total, N - total,
 514                                      offset + total);
 515
 516                 if (ret == -1)
 517                         return -1;
 518                 if (ret == 0)
 519                         return total;
 520
 521                 total += ret;
 522         }
 523         return (ssize_t)total;
 524 }
 525 /****************************************************************************
 526  An allocate file space call using the vfs interface.
 527  Allocates space for a file from a filedescriptor.
 528  Returns 0 on success, -1 on failure.
 529 ****************************************************************************/
 530
 531 int vfs_allocate_file_space(files_struct *fsp, uint64_t len)
 532 {
 533         int ret;
 534         SMB_STRUCT_STAT st;
 535         connection_struct *conn = fsp->conn;
 536         uint64_t space_avail;
 537         uint64_t bsize,dfree,dsize;
 538
 539         /*
 540          * Actually try and commit the space on disk....
 541          */
 542
 543         DEBUG(10,("vfs_allocate_file_space: file %s, len %.0f\n", fsp->fsp_name, (double)len ));
 544
 545         if (((SMB_OFF_T)len) < 0) {
 546                 DEBUG(0,("vfs_allocate_file_space: %s negative len requested.\n", fsp->fsp_name ));
 547                 errno = EINVAL;
 548                 return -1;
 549         }
 550
 551         ret = SMB_VFS_FSTAT(fsp, &st);
 552         if (ret == -1)
 553                 return ret;
 554
 555         if (len == (uint64_t)st.st_ex_size)
 556                 return 0;
 557
 558         if (len < (uint64_t)st.st_ex_size) {
 559                 /* Shrink - use ftruncate. */
 560
 561                 DEBUG(10,("vfs_allocate_file_space: file %s, shrink. Current size %.0f\n",
 562                                 fsp->fsp_name, (double)st.st_ex_size ));
 563
 564                 contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_ALLOC_SHRINK);
 565
 566                 flush_write_cache(fsp, SIZECHANGE_FLUSH);
 567                 if ((ret = SMB_VFS_FTRUNCATE(fsp, (SMB_OFF_T)len)) != -1) {
 568                         set_filelen_write_cache(fsp, len);
 569                 }
 570
 571                 contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_ALLOC_SHRINK);
 572
 573                 return ret;
 574         }
 575
 576         /* Grow - we need to test if we have enough space. */
 577
 578         contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_ALLOC_GROW);
 579         contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_ALLOC_GROW);
 580
 581         if (!lp_strict_allocate(SNUM(fsp->conn)))
 582                 return 0;
 583
 584         len -= st.st_ex_size;
 585         len /= 1024; /* Len is now number of 1k blocks needed. */
 586         space_avail = get_dfree_info(conn,fsp->fsp_name,False,&bsize,&dfree,&dsize);
 587         if (space_avail == (uint64_t)-1) {
 588                 return -1;
 589         }
 590
 591         DEBUG(10,("vfs_allocate_file_space: file %s, grow. Current size %.0f, needed blocks = %.0f, space avail = %.0f\n",
 592                         fsp->fsp_name, (double)st.st_ex_size, (double)len, (double)space_avail ));
 593
 594         if (len > space_avail) {
 595                 errno = ENOSPC;
 596                 return -1;
 597         }
 598
 599         return 0;
 600 }
 601
 602 /****************************************************************************
 603  A vfs set_filelen call.
 604  set the length of a file from a filedescriptor.
 605  Returns 0 on success, -1 on failure.
 606 ****************************************************************************/
 607
 608 int vfs_set_filelen(files_struct *fsp, SMB_OFF_T len)
 609 {
 610         int ret;
 611
 612         contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_SET_FILE_LEN);
 613
 614         DEBUG(10,("vfs_set_filelen: ftruncate %s to len %.0f\n", fsp->fsp_name, (double)len));
 615         flush_write_cache(fsp, SIZECHANGE_FLUSH);
 616         if ((ret = SMB_VFS_FTRUNCATE(fsp, len)) != -1) {
 617                 set_filelen_write_cache(fsp, len);
 618                 notify_fname(fsp->conn, NOTIFY_ACTION_MODIFIED,
 619                              FILE_NOTIFY_CHANGE_SIZE
 620                              | FILE_NOTIFY_CHANGE_ATTRIBUTES,
 621                              fsp->fsp_name);
 622         }
 623
 624         contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_SET_FILE_LEN);
 625
 626         return ret;
 627 }
 628
 629 /****************************************************************************
 630  A vfs fill sparse call.
 631  Writes zeros from the end of file to len, if len is greater than EOF.
 632  Used only by strict_sync.
 633  Returns 0 on success, -1 on failure.
 634 ****************************************************************************/
 635
 636 #define SPARSE_BUF_WRITE_SIZE (32*1024)
 637
 638 int vfs_fill_sparse(files_struct *fsp, SMB_OFF_T len)
 639 {
 640         int ret;
 641         SMB_STRUCT_STAT st;
 642         SMB_OFF_T offset;
 643         size_t total;
 644         size_t num_to_write;
 645         ssize_t pwrite_ret;
 646
 647         ret = SMB_VFS_FSTAT(fsp, &st);
 648         if (ret == -1) {
 649                 return ret;
 650         }
 651
 652         if (len <= st.st_ex_size) {
 653                 return 0;
 654         }
 655
 656         DEBUG(10,("vfs_fill_sparse: write zeros in file %s from len %.0f to len %.0f (%.0f bytes)\n",
 657                 fsp->fsp_name, (double)st.st_ex_size, (double)len, (double)(len - st.st_ex_size)));
 658
 659         contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_FILL_SPARSE);
 660
 661         flush_write_cache(fsp, SIZECHANGE_FLUSH);
 662
 663         if (!sparse_buf) {
 664                 sparse_buf = SMB_CALLOC_ARRAY(char, SPARSE_BUF_WRITE_SIZE);
 665                 if (!sparse_buf) {
 666                         errno = ENOMEM;
 667                         ret = -1;
 668                         goto out;
 669                 }
 670         }
 671
 672         offset = st.st_ex_size;
 673         num_to_write = len - st.st_ex_size;
 674         total = 0;
 675
 676         while (total < num_to_write) {
 677                 size_t curr_write_size = MIN(SPARSE_BUF_WRITE_SIZE, (num_to_write - total));
 678
 679                 pwrite_ret = SMB_VFS_PWRITE(fsp, sparse_buf, curr_write_size, offset + total);
 680                 if (pwrite_ret == -1) {
 681                         DEBUG(10,("vfs_fill_sparse: SMB_VFS_PWRITE for file %s failed with error %s\n",
 682                                 fsp->fsp_name, strerror(errno) ));
 683                         ret = -1;
 684                         goto out;
 685                 }
 686                 if (pwrite_ret == 0) {
 687                         ret = 0;
 688                         goto out;
 689                 }
 690
 691                 total += pwrite_ret;
 692         }
 693
 694         set_filelen_write_cache(fsp, len);
 695
 696         ret = 0;
 697  out:
 698         contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_FILL_SPARSE);
 699         return ret;
 700 }
 701
 702 /****************************************************************************
 703  Transfer some data (n bytes) between two file_struct's.
 704 ****************************************************************************/
 705
 706 static ssize_t vfs_read_fn(void *file, void *buf, size_t len)
 707 {
 708         struct files_struct *fsp = (struct files_struct *)file;
 709
 710         return SMB_VFS_READ(fsp, buf, len);
 711 }
 712
 713 static ssize_t vfs_write_fn(void *file, const void *buf, size_t len)
 714 {
 715         struct files_struct *fsp = (struct files_struct *)file;
 716
 717         return SMB_VFS_WRITE(fsp, buf, len);
 718 }
 719
 720 SMB_OFF_T vfs_transfer_file(files_struct *in, files_struct *out, SMB_OFF_T n)
 721 {
 722         return transfer_file_internal((void *)in, (void *)out, n,
 723                                       vfs_read_fn, vfs_write_fn);
 724 }
 725
 726 /*******************************************************************
 727  A vfs_readdir wrapper which just returns the file name.
 728 ********************************************************************/
 729
 730 char *vfs_readdirname(connection_struct *conn, void *p, SMB_STRUCT_STAT *sbuf)
 731 {
 732         SMB_STRUCT_DIRENT *ptr= NULL;
 733         char *dname;
 734
 735         if (!p)
 736                 return(NULL);
 737
 738         ptr = SMB_VFS_READDIR(conn, (DIR *)p, sbuf);
 739         if (!ptr)
 740                 return(NULL);
 741
 742         dname = ptr->d_name;
 743
 744 #ifdef NEXT2
 745         if (telldir(p) < 0)
 746                 return(NULL);
 747 #endif
 748
 749 #ifdef HAVE_BROKEN_READDIR_NAME
 750         /* using /usr/ucb/cc is BAD */
 751         dname = dname - 2;
 752 #endif
 753
 754         return(dname);
 755 }
 756
 757 /*******************************************************************
 758  A wrapper for vfs_chdir().
 759 ********************************************************************/
 760
 761 int vfs_ChDir(connection_struct *conn, const char *path)
 762 {
 763         int res;
 764
 765         if (!LastDir) {
 766                 LastDir = SMB_STRDUP("");
 767         }
 768
 769         if (strcsequal(path,"."))
 770                 return(0);
 771
 772         if (*path == '/' && strcsequal(LastDir,path))
 773                 return(0);
 774
 775         DEBUG(4,("vfs_ChDir to %s\n",path));
 776
 777         res = SMB_VFS_CHDIR(conn,path);
 778         if (!res) {
 779                 SAFE_FREE(LastDir);
 780                 LastDir = SMB_STRDUP(path);
 781         }
 782         return(res);
 783 }
 784
 785 /*******************************************************************
 786  Return the absolute current directory path - given a UNIX pathname.
 787  Note that this path is returned in DOS format, not UNIX
 788  format. Note this can be called with conn == NULL.
 789 ********************************************************************/
 790
 791 char *vfs_GetWd(TALLOC_CTX *ctx, connection_struct *conn)
 792 {
 793         char s[PATH_MAX+1];
 794         SMB_STRUCT_STAT st, st2;
 795         char *result;
 796         DATA_BLOB cache_value;
 797         struct file_id key;
 798
 799         *s = 0;
 800
 801         if (!lp_getwd_cache()) {
 802                 goto nocache;
 803         }
 804
 805         SET_STAT_INVALID(st);
 806
 807         if (SMB_VFS_STAT(conn, ".",&st) == -1) {
 808                 /*
 809                  * Known to fail for root: the directory may be NFS-mounted
 810                  * and exported with root_squash (so has no root access).
 811                  */
 812                 DEBUG(1,("vfs_GetWd: couldn't stat \".\" error %s "
 813                          "(NFS problem ?)\n", strerror(errno) ));
 814                 goto nocache;
 815         }
 816
 817         key = vfs_file_id_from_sbuf(conn, &st);
 818
 819         if (!memcache_lookup(smbd_memcache(), GETWD_CACHE,
 820                              data_blob_const(&key, sizeof(key)),
 821                              &cache_value)) {
 822                 goto nocache;
 823         }
 824
 825         SMB_ASSERT((cache_value.length > 0)
 826                    && (cache_value.data[cache_value.length-1] == '\0'));
 827
 828         if ((SMB_VFS_STAT(conn, (char *)cache_value.data, &st2) == 0)
 829             && (st.st_ex_dev == st2.st_ex_dev) && (st.st_ex_ino == st2.st_ex_ino)
 830             && (S_ISDIR(st.st_ex_mode))) {
 831                 /*
 832                  * Ok, we're done
 833                  */
 834                 result = talloc_strdup(ctx, (char *)cache_value.data);
 835                 if (result == NULL) {
 836                         errno = ENOMEM;
 837                 }
 838                 return result;
 839         }
 840
 841  nocache:
 842
 843         /*
 844          * We don't have the information to hand so rely on traditional
 845          * methods. The very slow getcwd, which spawns a process on some
 846          * systems, or the not quite so bad getwd.
 847          */
 848
 849         if (!SMB_VFS_GETWD(conn,s)) {
 850                 DEBUG(0, ("vfs_GetWd: SMB_VFS_GETWD call failed: %s\n",
 851                           strerror(errno)));
 852                 return NULL;
 853         }
 854
 855         if (lp_getwd_cache() && VALID_STAT(st)) {
 856                 key = vfs_file_id_from_sbuf(conn, &st);
 857
 858                 memcache_add(smbd_memcache(), GETWD_CACHE,
 859                              data_blob_const(&key, sizeof(key)),
 860                              data_blob_const(s, strlen(s)+1));
 861         }
 862
 863         result = talloc_strdup(ctx, s);
 864         if (result == NULL) {
 865                 errno = ENOMEM;
 866         }
 867         return result;
 868 }
 869
 870 /*******************************************************************
 871  Reduce a file name, removing .. elements and checking that
 872  it is below dir in the heirachy. This uses realpath.
 873 ********************************************************************/
 874
 875 NTSTATUS check_reduced_name(connection_struct *conn, const char *fname)
 876 {
 877 #ifdef REALPATH_TAKES_NULL
 878         bool free_resolved_name = True;
 879 #else
 880         char resolved_name_buf[PATH_MAX+1];
 881         bool free_resolved_name = False;
 882 #endif
 883         char *resolved_name = NULL;
 884         char *p = NULL;
 885
 886         DEBUG(3,("reduce_name [%s] [%s]\n", fname, conn->connectpath));
 887
 888 #ifdef REALPATH_TAKES_NULL
 889         resolved_name = SMB_VFS_REALPATH(conn,fname,NULL);
 890 #else
 891         resolved_name = SMB_VFS_REALPATH(conn,fname,resolved_name_buf);
 892 #endif
 893
 894         if (!resolved_name) {
 895                 switch (errno) {
 896                         case ENOTDIR:
 897                                 DEBUG(3,("reduce_name: Component not a directory in getting realpath for %s\n", fname));
 898                                 return map_nt_error_from_unix(errno);
 899                         case ENOENT:
 900                         {
 901                                 TALLOC_CTX *ctx = talloc_tos();
 902                                 char *tmp_fname = NULL;
 903                                 char *last_component = NULL;
 904                                 /* Last component didn't exist. Remove it and try and canonicalise the directory. */
 905
 906                                 tmp_fname = talloc_strdup(ctx, fname);
 907                                 if (!tmp_fname) {
 908                                         return NT_STATUS_NO_MEMORY;
 909                                 }
 910                                 p = strrchr_m(tmp_fname, '/');
 911                                 if (p) {
 912                                         *p++ = '\0';
 913                                         last_component = p;
 914                                 } else {
 915                                         last_component = tmp_fname;
 916                                         tmp_fname = talloc_strdup(ctx,
 917                                                         ".");
 918                                         if (!tmp_fname) {
 919                                                 return NT_STATUS_NO_MEMORY;
 920                                         }
 921                                 }
 922
 923 #ifdef REALPATH_TAKES_NULL
 924                                 resolved_name = SMB_VFS_REALPATH(conn,tmp_fname,NULL);
 925 #else
 926                                 resolved_name = SMB_VFS_REALPATH(conn,tmp_fname,resolved_name_buf);
 927 #endif
 928                                 if (!resolved_name) {
 929                                         DEBUG(3,("reduce_name: couldn't get realpath for %s\n", fname));
 930                                         return map_nt_error_from_unix(errno);
 931                                 }
 932                                 tmp_fname = talloc_asprintf(ctx,
 933                                                 "%s/%s",
 934                                                 resolved_name,
 935                                                 last_component);
 936                                 if (!tmp_fname) {
 937                                         return NT_STATUS_NO_MEMORY;
 938                                 }
 939 #ifdef REALPATH_TAKES_NULL
 940                                 SAFE_FREE(resolved_name);
 941                                 resolved_name = SMB_STRDUP(tmp_fname);
 942                                 if (!resolved_name) {
 943                                         DEBUG(0,("reduce_name: malloc fail for %s\n", tmp_fname));
 944                                         return NT_STATUS_NO_MEMORY;
 945                                 }
 946 #else
 947                                 safe_strcpy(resolved_name_buf, tmp_fname, PATH_MAX);
 948                                 resolved_name = resolved_name_buf;
 949 #endif
 950                                 break;
 951                         }
 952                         default:
 953                                 DEBUG(1,("reduce_name: couldn't get realpath for %s\n", fname));
 954                                 return map_nt_error_from_unix(errno);
 955                 }
 956         }
 957
 958         DEBUG(10,("reduce_name realpath [%s] -> [%s]\n", fname, resolved_name));
 959
 960         if (*resolved_name != '/') {
 961                 DEBUG(0,("reduce_name: realpath doesn't return absolute paths !\n"));
 962                 if (free_resolved_name) {
 963                         SAFE_FREE(resolved_name);
 964                 }
 965                 return NT_STATUS_OBJECT_NAME_INVALID;
 966         }
 967
 968         /* Check for widelinks allowed. */
 969         if (!lp_widelinks(SNUM(conn))) {
 970                     const char *conn_rootdir;
 971
 972                     conn_rootdir = SMB_VFS_CONNECTPATH(conn, fname);
 973                     if (conn_rootdir == NULL) {
 974                             DEBUG(2, ("check_reduced_name: Could not get conn_rootdir\n"));
 975                             if (free_resolved_name) {
 976                                     SAFE_FREE(resolved_name);
 977                             }
 978                             return NT_STATUS_ACCESS_DENIED;
 979                     }
 980
 981                     if (strncmp(conn_rootdir, resolved_name,
 982                                 strlen(conn_rootdir)) != 0) {
 983                             DEBUG(2, ("reduce_name: Bad access attempt: %s is "
 984                                       "a symlink outside the share path",
 985                                       fname));
 986                             if (free_resolved_name) {
 987                                     SAFE_FREE(resolved_name);
 988                             }
 989                             return NT_STATUS_ACCESS_DENIED;
 990                     }
 991         }
 992
 993         /* Check if we are allowing users to follow symlinks */
 994         /* Patch from David Clerc <David.Clerc@cui.unige.ch>
 995                 University of Geneva */
 996
 997 #ifdef S_ISLNK
 998         if (!lp_symlinks(SNUM(conn))) {
 999                 SMB_STRUCT_STAT statbuf;
1000                 if ( (SMB_VFS_LSTAT(conn,fname,&statbuf) != -1) &&
1001                                 (S_ISLNK(statbuf.st_ex_mode)) ) {
1002                         if (free_resolved_name) {
1003                                 SAFE_FREE(resolved_name);
1004                         }
1005                         DEBUG(3,("reduce_name: denied: file path name %s is a symlink\n",resolved_name));
1006                         return NT_STATUS_ACCESS_DENIED;
1007                 }
1008         }
1009 #endif
1010
1011         DEBUG(3,("reduce_name: %s reduced to %s\n", fname, resolved_name));
1012         if (free_resolved_name) {
1013                 SAFE_FREE(resolved_name);
1014         }
1015         return NT_STATUS_OK;
1016 }