2 Unix SMB/Netbios implementation.
4 VFS initialisation and support functions
5 Copyright (C) Tim Potter 1999
6 Copyright (C) Alexander Bokovoy 2002
7 Copyright (C) James Peach 2006
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.
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.
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/>.
22 This work was sponsored by Optifacio Software Services, Inc.
26 #include "smbd/globals.h"
29 #define DBGC_CLASS DBGC_VFS
33 struct vfs_init_function_entry {
35 const vfs_op_tuple *vfs_op_tuples;
36 struct vfs_init_function_entry *prev, *next;
39 /****************************************************************************
40 maintain the list of available backends
41 ****************************************************************************/
43 static struct vfs_init_function_entry *vfs_find_backend_entry(const char *name)
45 struct vfs_init_function_entry *entry = backends;
47 DEBUG(10, ("vfs_find_backend_entry called for %s\n", name));
50 if (strcmp(entry->name, name)==0) return entry;
57 NTSTATUS smb_register_vfs(int version, const char *name, const vfs_op_tuple *vfs_op_tuples)
59 struct vfs_init_function_entry *entry = backends;
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;
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;
75 if (vfs_find_backend_entry(name)) {
76 DEBUG(0,("VFS module %s already loaded!\n", name));
77 return NT_STATUS_OBJECT_NAME_COLLISION;
80 entry = SMB_XMALLOC_P(struct vfs_init_function_entry);
81 entry->name = smb_xstrdup(name);
82 entry->vfs_op_tuples = vfs_op_tuples;
84 DLIST_ADD(backends, entry);
85 DEBUG(5, ("Successfully added vfs backend '%s'\n", name));
89 /****************************************************************************
90 initialise default vfs hooks
91 ****************************************************************************/
93 static void vfs_init_default(connection_struct *conn)
95 DEBUG(3, ("Initialising default vfs hooks\n"));
96 vfs_init_custom(conn, DEFAULT_VFS_MODULE_NAME);
99 /****************************************************************************
100 initialise custom vfs hooks
101 ****************************************************************************/
103 static inline void vfs_set_operation(struct vfs_ops * vfs, vfs_op_type which,
104 struct vfs_handle_struct * handle, void * op)
106 ((struct vfs_handle_struct **)&vfs->handles)[which] = handle;
107 ((void **)(void *)&vfs->ops)[which] = op;
110 bool vfs_init_custom(connection_struct *conn, const char *vfs_object)
112 const vfs_op_tuple *ops;
113 char *module_path = NULL;
114 char *module_name = NULL;
115 char *module_param = NULL, *p;
117 vfs_handle_struct *handle;
118 const struct vfs_init_function_entry *entry;
120 if (!conn||!vfs_object||!vfs_object[0]) {
121 DEBUG(0,("vfs_init_custon() called with NULL pointer or emtpy vfs_object!\n"));
129 DEBUG(3, ("Initialising custom vfs hooks from [%s]\n", vfs_object));
131 module_path = smb_xstrdup(vfs_object);
133 p = strchr_m(module_path, ':');
138 trim_char(module_param, ' ', ' ');
141 trim_char(module_path, ' ', ' ');
143 module_name = smb_xstrdup(module_path);
145 if ((module_name[0] == '/') &&
146 (strcmp(module_path, DEFAULT_VFS_MODULE_NAME) != 0)) {
149 * Extract the module name from the path. Just use the base
150 * name of the last path component.
153 SAFE_FREE(module_name);
154 module_name = smb_xstrdup(strrchr_m(module_path, '/')+1);
156 p = strchr_m(module_name, '.');
163 /* First, try to load the module with the new module system */
164 if((entry = vfs_find_backend_entry(module_name)) ||
165 (NT_STATUS_IS_OK(smb_probe_module("vfs", module_path)) &&
166 (entry = vfs_find_backend_entry(module_name)))) {
168 DEBUGADD(5,("Successfully loaded vfs module [%s] with the new modules system\n", vfs_object));
170 if ((ops = entry->vfs_op_tuples) == NULL) {
171 DEBUG(0, ("entry->vfs_op_tuples==NULL for [%s] failed\n", vfs_object));
175 DEBUG(0,("Can't find a vfs module [%s]\n",vfs_object));
179 handle = TALLOC_ZERO_P(conn, vfs_handle_struct);
181 DEBUG(0,("TALLOC_ZERO() failed!\n"));
184 memcpy(&handle->vfs_next, &conn->vfs, sizeof(struct vfs_ops));
187 handle->param = talloc_strdup(conn, module_param);
189 DLIST_ADD(conn->vfs_handles, handle);
191 for(i=0; ops[i].op != NULL; i++) {
192 DEBUG(5, ("Checking operation #%d (type %d, layer %d)\n", i, ops[i].type, ops[i].layer));
193 if(ops[i].layer == SMB_VFS_LAYER_OPAQUE) {
194 /* If this operation was already made opaque by different module, it
195 * will be overridden here.
197 DEBUGADD(5, ("Making operation type %d opaque [module %s]\n", ops[i].type, vfs_object));
198 vfs_set_operation(&conn->vfs_opaque, ops[i].type, handle, ops[i].op);
200 /* Change current VFS disposition*/
201 DEBUGADD(5, ("Accepting operation type %d from module %s\n", ops[i].type, vfs_object));
202 vfs_set_operation(&conn->vfs, ops[i].type, handle, ops[i].op);
205 SAFE_FREE(module_path);
206 SAFE_FREE(module_name);
210 SAFE_FREE(module_path);
211 SAFE_FREE(module_name);
215 /*****************************************************************
216 Allow VFS modules to extend files_struct with VFS-specific state.
217 This will be ok for small numbers of extensions, but might need to
218 be refactored if it becomes more widely used.
219 ******************************************************************/
221 #define EXT_DATA_AREA(e) ((uint8 *)(e) + sizeof(struct vfs_fsp_data))
223 void *vfs_add_fsp_extension_notype(vfs_handle_struct *handle, files_struct *fsp, size_t ext_size)
225 struct vfs_fsp_data *ext;
228 /* Prevent VFS modules adding multiple extensions. */
229 if ((ext_data = vfs_fetch_fsp_extension(handle, fsp))) {
233 ext = (struct vfs_fsp_data *)TALLOC_ZERO(
234 handle->conn, sizeof(struct vfs_fsp_data) + ext_size);
240 ext->next = fsp->vfs_extension;
241 fsp->vfs_extension = ext;
242 return EXT_DATA_AREA(ext);
245 void vfs_remove_fsp_extension(vfs_handle_struct *handle, files_struct *fsp)
247 struct vfs_fsp_data *curr;
248 struct vfs_fsp_data *prev;
250 for (curr = fsp->vfs_extension, prev = NULL;
252 prev = curr, curr = curr->next) {
253 if (curr->owner == handle) {
255 prev->next = curr->next;
257 fsp->vfs_extension = curr->next;
265 void *vfs_memctx_fsp_extension(vfs_handle_struct *handle, files_struct *fsp)
267 struct vfs_fsp_data *head;
269 for (head = fsp->vfs_extension; head; head = head->next) {
270 if (head->owner == handle) {
278 void *vfs_fetch_fsp_extension(vfs_handle_struct *handle, files_struct *fsp)
280 struct vfs_fsp_data *head;
282 head = (struct vfs_fsp_data *)vfs_memctx_fsp_extension(handle, fsp);
284 return EXT_DATA_AREA(head);
292 /*****************************************************************
294 ******************************************************************/
296 bool smbd_vfs_init(connection_struct *conn)
298 const char **vfs_objects;
302 /* Normal share - initialise with disk access functions */
303 vfs_init_default(conn);
304 vfs_objects = lp_vfs_objects(SNUM(conn));
306 /* Override VFS functions if 'vfs object' was not specified*/
307 if (!vfs_objects || !vfs_objects[0])
310 for (i=0; vfs_objects[i] ;) {
314 for (j=i-1; j >= 0; j--) {
315 if (!vfs_init_custom(conn, vfs_objects[j])) {
316 DEBUG(0, ("smbd_vfs_init: vfs_init_custom failed for %s\n", vfs_objects[j]));
323 /*******************************************************************
324 Check if directory exists.
325 ********************************************************************/
327 bool vfs_directory_exist(connection_struct *conn, const char *dname, SMB_STRUCT_STAT *st)
335 if (SMB_VFS_STAT(conn,dname,st) != 0)
338 ret = S_ISDIR(st->st_mode);
345 /*******************************************************************
346 Check if an object exists in the vfs.
347 ********************************************************************/
349 bool vfs_object_exist(connection_struct *conn,const char *fname,SMB_STRUCT_STAT *sbuf)
358 if (SMB_VFS_STAT(conn,fname,sbuf) == -1)
363 /*******************************************************************
364 Check if a file exists in the vfs.
365 ********************************************************************/
367 bool vfs_file_exist(connection_struct *conn, const char *fname,SMB_STRUCT_STAT *sbuf)
376 if (SMB_VFS_STAT(conn,fname,sbuf) == -1)
378 return(S_ISREG(sbuf->st_mode));
381 /****************************************************************************
382 Read data from fsp on the vfs. (note: EINTR re-read differs from vfs_write_data)
383 ****************************************************************************/
385 ssize_t vfs_read_data(files_struct *fsp, char *buf, size_t byte_count)
389 while (total < byte_count)
391 ssize_t ret = SMB_VFS_READ(fsp, buf + total,
394 if (ret == 0) return total;
403 return (ssize_t)total;
406 ssize_t vfs_pread_data(files_struct *fsp, char *buf,
407 size_t byte_count, SMB_OFF_T offset)
411 while (total < byte_count)
413 ssize_t ret = SMB_VFS_PREAD(fsp, buf + total,
414 byte_count - total, offset + total);
416 if (ret == 0) return total;
425 return (ssize_t)total;
428 /****************************************************************************
429 Write data to a fd on the vfs.
430 ****************************************************************************/
432 ssize_t vfs_write_data(struct smb_request *req,
440 if (req && req->unread_bytes) {
441 SMB_ASSERT(req->unread_bytes == N);
442 /* VFS_RECVFILE must drain the socket
443 * before returning. */
444 req->unread_bytes = 0;
445 return SMB_VFS_RECVFILE(smbd_server_fd(),
452 ret = SMB_VFS_WRITE(fsp, buffer + total, N - total);
461 return (ssize_t)total;
464 ssize_t vfs_pwrite_data(struct smb_request *req,
473 if (req && req->unread_bytes) {
474 SMB_ASSERT(req->unread_bytes == N);
475 /* VFS_RECVFILE must drain the socket
476 * before returning. */
477 req->unread_bytes = 0;
478 return SMB_VFS_RECVFILE(smbd_server_fd(),
485 ret = SMB_VFS_PWRITE(fsp, buffer + total, N - total,
495 return (ssize_t)total;
497 /****************************************************************************
498 An allocate file space call using the vfs interface.
499 Allocates space for a file from a filedescriptor.
500 Returns 0 on success, -1 on failure.
501 ****************************************************************************/
503 int vfs_allocate_file_space(files_struct *fsp, uint64_t len)
507 connection_struct *conn = fsp->conn;
508 uint64_t space_avail;
509 uint64_t bsize,dfree,dsize;
511 release_level_2_oplocks_on_change(fsp);
514 * Actually try and commit the space on disk....
517 DEBUG(10,("vfs_allocate_file_space: file %s, len %.0f\n", fsp->fsp_name, (double)len ));
519 if (((SMB_OFF_T)len) < 0) {
520 DEBUG(0,("vfs_allocate_file_space: %s negative len requested.\n", fsp->fsp_name ));
525 ret = SMB_VFS_FSTAT(fsp, &st);
529 if (len == (uint64_t)st.st_size)
532 if (len < (uint64_t)st.st_size) {
533 /* Shrink - use ftruncate. */
535 DEBUG(10,("vfs_allocate_file_space: file %s, shrink. Current size %.0f\n",
536 fsp->fsp_name, (double)st.st_size ));
538 flush_write_cache(fsp, SIZECHANGE_FLUSH);
539 if ((ret = SMB_VFS_FTRUNCATE(fsp, (SMB_OFF_T)len)) != -1) {
540 set_filelen_write_cache(fsp, len);
545 /* Grow - we need to test if we have enough space. */
547 if (!lp_strict_allocate(SNUM(fsp->conn)))
551 len /= 1024; /* Len is now number of 1k blocks needed. */
552 space_avail = get_dfree_info(conn,fsp->fsp_name,False,&bsize,&dfree,&dsize);
553 if (space_avail == (uint64_t)-1) {
557 DEBUG(10,("vfs_allocate_file_space: file %s, grow. Current size %.0f, needed blocks = %.0f, space avail = %.0f\n",
558 fsp->fsp_name, (double)st.st_size, (double)len, (double)space_avail ));
560 if (len > space_avail) {
568 /****************************************************************************
569 A vfs set_filelen call.
570 set the length of a file from a filedescriptor.
571 Returns 0 on success, -1 on failure.
572 ****************************************************************************/
574 int vfs_set_filelen(files_struct *fsp, SMB_OFF_T len)
578 release_level_2_oplocks_on_change(fsp);
579 DEBUG(10,("vfs_set_filelen: ftruncate %s to len %.0f\n", fsp->fsp_name, (double)len));
580 flush_write_cache(fsp, SIZECHANGE_FLUSH);
581 if ((ret = SMB_VFS_FTRUNCATE(fsp, len)) != -1) {
582 set_filelen_write_cache(fsp, len);
583 notify_fname(fsp->conn, NOTIFY_ACTION_MODIFIED,
584 FILE_NOTIFY_CHANGE_SIZE
585 | FILE_NOTIFY_CHANGE_ATTRIBUTES,
592 /****************************************************************************
593 A vfs fill sparse call.
594 Writes zeros from the end of file to len, if len is greater than EOF.
595 Used only by strict_sync.
596 Returns 0 on success, -1 on failure.
597 ****************************************************************************/
599 #define SPARSE_BUF_WRITE_SIZE (32*1024)
601 int vfs_fill_sparse(files_struct *fsp, SMB_OFF_T len)
610 release_level_2_oplocks_on_change(fsp);
611 ret = SMB_VFS_FSTAT(fsp, &st);
616 if (len <= st.st_size) {
620 DEBUG(10,("vfs_fill_sparse: write zeros in file %s from len %.0f to len %.0f (%.0f bytes)\n",
621 fsp->fsp_name, (double)st.st_size, (double)len, (double)(len - st.st_size)));
623 flush_write_cache(fsp, SIZECHANGE_FLUSH);
626 sparse_buf = SMB_CALLOC_ARRAY(char, SPARSE_BUF_WRITE_SIZE);
634 num_to_write = len - st.st_size;
637 while (total < num_to_write) {
638 size_t curr_write_size = MIN(SPARSE_BUF_WRITE_SIZE, (num_to_write - total));
640 pwrite_ret = SMB_VFS_PWRITE(fsp, sparse_buf, curr_write_size, offset + total);
641 if (pwrite_ret == -1) {
642 DEBUG(10,("vfs_fill_sparse: SMB_VFS_PWRITE for file %s failed with error %s\n",
643 fsp->fsp_name, strerror(errno) ));
646 if (pwrite_ret == 0) {
653 set_filelen_write_cache(fsp, len);
657 /****************************************************************************
658 Transfer some data (n bytes) between two file_struct's.
659 ****************************************************************************/
661 static ssize_t vfs_read_fn(void *file, void *buf, size_t len)
663 struct files_struct *fsp = (struct files_struct *)file;
665 return SMB_VFS_READ(fsp, buf, len);
668 static ssize_t vfs_write_fn(void *file, const void *buf, size_t len)
670 struct files_struct *fsp = (struct files_struct *)file;
672 return SMB_VFS_WRITE(fsp, buf, len);
675 SMB_OFF_T vfs_transfer_file(files_struct *in, files_struct *out, SMB_OFF_T n)
677 return transfer_file_internal((void *)in, (void *)out, n,
678 vfs_read_fn, vfs_write_fn);
681 /*******************************************************************
682 A vfs_readdir wrapper which just returns the file name.
683 ********************************************************************/
685 char *vfs_readdirname(connection_struct *conn, void *p)
687 SMB_STRUCT_DIRENT *ptr= NULL;
693 ptr = SMB_VFS_READDIR(conn, (DIR *)p);
704 #ifdef HAVE_BROKEN_READDIR_NAME
705 /* using /usr/ucb/cc is BAD */
712 /*******************************************************************
713 A wrapper for vfs_chdir().
714 ********************************************************************/
716 int vfs_ChDir(connection_struct *conn, const char *path)
721 LastDir = SMB_STRDUP("");
724 if (strcsequal(path,"."))
727 if (*path == '/' && strcsequal(LastDir,path))
730 DEBUG(4,("vfs_ChDir to %s\n",path));
732 res = SMB_VFS_CHDIR(conn,path);
735 LastDir = SMB_STRDUP(path);
740 /*******************************************************************
741 Return the absolute current directory path - given a UNIX pathname.
742 Note that this path is returned in DOS format, not UNIX
743 format. Note this can be called with conn == NULL.
744 ********************************************************************/
746 struct getwd_cache_key {
751 char *vfs_GetWd(TALLOC_CTX *ctx, connection_struct *conn)
754 SMB_STRUCT_STAT st, st2;
756 DATA_BLOB cache_value;
757 struct getwd_cache_key key;
761 if (!lp_getwd_cache()) {
765 SET_STAT_INVALID(st);
767 if (SMB_VFS_STAT(conn, ".",&st) == -1) {
769 * Known to fail for root: the directory may be NFS-mounted
770 * and exported with root_squash (so has no root access).
772 DEBUG(1,("vfs_GetWd: couldn't stat \".\" error %s "
773 "(NFS problem ?)\n", strerror(errno) ));
777 ZERO_STRUCT(key); /* unlikely, but possible padding */
781 if (!memcache_lookup(smbd_memcache(), GETWD_CACHE,
782 data_blob_const(&key, sizeof(key)),
787 SMB_ASSERT((cache_value.length > 0)
788 && (cache_value.data[cache_value.length-1] == '\0'));
790 if ((SMB_VFS_STAT(conn, (char *)cache_value.data, &st2) == 0)
791 && (st.st_dev == st2.st_dev) && (st.st_ino == st2.st_ino)
792 && (S_ISDIR(st.st_mode))) {
796 result = talloc_strdup(ctx, (char *)cache_value.data);
797 if (result == NULL) {
806 * We don't have the information to hand so rely on traditional
807 * methods. The very slow getcwd, which spawns a process on some
808 * systems, or the not quite so bad getwd.
811 if (!SMB_VFS_GETWD(conn,s)) {
812 DEBUG(0, ("vfs_GetWd: SMB_VFS_GETWD call failed: %s\n",
817 if (lp_getwd_cache() && VALID_STAT(st)) {
818 ZERO_STRUCT(key); /* unlikely, but possible padding */
822 memcache_add(smbd_memcache(), GETWD_CACHE,
823 data_blob_const(&key, sizeof(key)),
824 data_blob_const(s, strlen(s)+1));
827 result = talloc_strdup(ctx, s);
828 if (result == NULL) {
834 /*******************************************************************
835 Reduce a file name, removing .. elements and checking that
836 it is below dir in the heirachy. This uses realpath.
837 ********************************************************************/
839 NTSTATUS check_reduced_name(connection_struct *conn, const char *fname)
841 #ifdef REALPATH_TAKES_NULL
842 bool free_resolved_name = True;
844 char resolved_name_buf[PATH_MAX+1];
845 bool free_resolved_name = False;
847 char *resolved_name = NULL;
848 size_t con_path_len = strlen(conn->connectpath);
851 DEBUG(3,("reduce_name [%s] [%s]\n", fname, conn->connectpath));
853 #ifdef REALPATH_TAKES_NULL
854 resolved_name = SMB_VFS_REALPATH(conn,fname,NULL);
856 resolved_name = SMB_VFS_REALPATH(conn,fname,resolved_name_buf);
859 if (!resolved_name) {
862 DEBUG(3,("reduce_name: Component not a directory in getting realpath for %s\n", fname));
863 return map_nt_error_from_unix(errno);
866 TALLOC_CTX *ctx = talloc_tos();
867 char *tmp_fname = NULL;
868 char *last_component = NULL;
869 /* Last component didn't exist. Remove it and try and canonicalise the directory. */
871 tmp_fname = talloc_strdup(ctx, fname);
873 return NT_STATUS_NO_MEMORY;
875 p = strrchr_m(tmp_fname, '/');
880 last_component = tmp_fname;
881 tmp_fname = talloc_strdup(ctx,
884 return NT_STATUS_NO_MEMORY;
888 #ifdef REALPATH_TAKES_NULL
889 resolved_name = SMB_VFS_REALPATH(conn,tmp_fname,NULL);
891 resolved_name = SMB_VFS_REALPATH(conn,tmp_fname,resolved_name_buf);
893 if (!resolved_name) {
894 DEBUG(3,("reduce_name: couldn't get realpath for %s\n", fname));
895 return map_nt_error_from_unix(errno);
897 tmp_fname = talloc_asprintf(ctx,
902 return NT_STATUS_NO_MEMORY;
904 #ifdef REALPATH_TAKES_NULL
905 SAFE_FREE(resolved_name);
906 resolved_name = SMB_STRDUP(tmp_fname);
907 if (!resolved_name) {
908 DEBUG(0,("reduce_name: malloc fail for %s\n", tmp_fname));
909 return NT_STATUS_NO_MEMORY;
912 safe_strcpy(resolved_name_buf, tmp_fname, PATH_MAX);
913 resolved_name = resolved_name_buf;
918 DEBUG(1,("reduce_name: couldn't get realpath for %s\n", fname));
919 return map_nt_error_from_unix(errno);
923 DEBUG(10,("reduce_name realpath [%s] -> [%s]\n", fname, resolved_name));
925 if (*resolved_name != '/') {
926 DEBUG(0,("reduce_name: realpath doesn't return absolute paths !\n"));
927 if (free_resolved_name) {
928 SAFE_FREE(resolved_name);
930 return NT_STATUS_OBJECT_NAME_INVALID;
933 /* Check for widelinks allowed. */
934 if (!lp_widelinks(SNUM(conn)) && (strncmp(conn->connectpath, resolved_name, con_path_len) != 0)) {
935 DEBUG(2, ("reduce_name: Bad access attempt: %s is a symlink outside the share path", fname));
936 if (free_resolved_name) {
937 SAFE_FREE(resolved_name);
939 return NT_STATUS_ACCESS_DENIED;
942 /* Check if we are allowing users to follow symlinks */
943 /* Patch from David Clerc <David.Clerc@cui.unige.ch>
944 University of Geneva */
947 if (!lp_symlinks(SNUM(conn))) {
948 SMB_STRUCT_STAT statbuf;
949 if ( (SMB_VFS_LSTAT(conn,fname,&statbuf) != -1) &&
950 (S_ISLNK(statbuf.st_mode)) ) {
951 if (free_resolved_name) {
952 SAFE_FREE(resolved_name);
954 DEBUG(3,("reduce_name: denied: file path name %s is a symlink\n",resolved_name));
955 return NT_STATUS_ACCESS_DENIED;
960 DEBUG(3,("reduce_name: %s reduced to %s\n", fname, resolved_name));
961 if (free_resolved_name) {
962 SAFE_FREE(resolved_name);