2 * Store streams in a separate subdirectory
4 * Copyright (C) Volker Lendecke, 2007
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
21 #include "smbd/smbd.h"
22 #include "system/filesys.h"
25 #define DBGC_CLASS DBGC_VFS
28 * Excerpt from a mail from tridge:
30 * Volker, what I'm thinking of is this:
31 * /mount-point/.streams/XX/YY/aaaa.bbbb/namedstream1
32 * /mount-point/.streams/XX/YY/aaaa.bbbb/namedstream2
34 * where XX/YY is a 2 level hash based on the fsid/inode. "aaaa.bbbb"
35 * is the fsid/inode. "namedstreamX" is a file named after the stream
39 static uint32_t hash_fn(DATA_BLOB key)
41 uint32_t value; /* Used to compute the hash value. */
42 uint32_t i; /* Used to cycle through random values. */
44 /* Set the initial value from the key size. */
45 for (value = 0x238F13AF * key.length, i=0; i < key.length; i++)
46 value = (value + (key.data[i] << (i*5 % 24)));
48 return (1103515243 * value + 12345);
52 * With the hashing scheme based on the inode we need to protect against
53 * streams showing up on files with re-used inodes. This can happen if we
54 * create a stream directory from within Samba, and a local process or NFS
55 * client deletes the file without deleting the streams directory. When the
56 * inode is re-used and the stream directory is still around, the streams in
57 * there would be show up as belonging to the new file.
59 * There are several workarounds for this, probably the easiest one is on
60 * systems which have a true birthtime stat element: When the file has a later
61 * birthtime than the streams directory, then we have to recreate the
64 * The other workaround is to somehow mark the file as generated by Samba with
65 * something that a NFS client would not do. The closest one is a special
66 * xattr value being set. On systems which do not support xattrs, it might be
67 * an option to put in a special ACL entry for a non-existing group.
70 static bool file_is_valid(vfs_handle_struct *handle, const char *path)
74 DEBUG(10, ("file_is_valid (%s) called\n", path));
76 if (SMB_VFS_GETXATTR(handle->conn, path, SAMBA_XATTR_MARKER,
77 &buf, sizeof(buf)) != sizeof(buf)) {
78 DEBUG(10, ("GETXATTR failed: %s\n", strerror(errno)));
83 DEBUG(10, ("got wrong buffer content: '%c'\n", buf));
90 static bool mark_file_valid(vfs_handle_struct *handle, const char *path)
95 DEBUG(10, ("marking file %s as valid\n", path));
97 ret = SMB_VFS_SETXATTR(handle->conn, path, SAMBA_XATTR_MARKER,
98 &buf, sizeof(buf), 0);
101 DEBUG(10, ("SETXATTR failed: %s\n", strerror(errno)));
109 * Given an smb_filename, determine the stream directory using the file's
112 static char *stream_dir(vfs_handle_struct *handle,
113 const struct smb_filename *smb_fname,
114 const SMB_STRUCT_STAT *base_sbuf, bool create_it)
117 struct smb_filename *smb_fname_hash = NULL;
119 SMB_STRUCT_STAT base_sbuf_tmp;
120 uint8_t first, second;
129 check_valid = lp_parm_bool(SNUM(handle->conn),
130 "streams_depot", "check_valid", true);
132 tmp = talloc_asprintf(talloc_tos(), "%s/.streams", handle->conn->connectpath);
139 rootdir = lp_parm_const_string(
140 SNUM(handle->conn), "streams_depot", "directory",
143 /* Stat the base file if it hasn't already been done. */
144 if (base_sbuf == NULL) {
145 struct smb_filename *smb_fname_base = NULL;
147 status = create_synthetic_smb_fname(talloc_tos(),
148 smb_fname->base_name,
151 if (!NT_STATUS_IS_OK(status)) {
152 errno = map_errno_from_nt_status(status);
155 if (SMB_VFS_NEXT_STAT(handle, smb_fname_base) == -1) {
156 TALLOC_FREE(smb_fname_base);
159 base_sbuf_tmp = smb_fname_base->st;
160 TALLOC_FREE(smb_fname_base);
162 base_sbuf_tmp = *base_sbuf;
165 id = SMB_VFS_FILE_ID_CREATE(handle->conn, &base_sbuf_tmp);
167 push_file_id_16((char *)id_buf, &id);
169 hash = hash_fn(data_blob_const(id_buf, sizeof(id_buf)));
172 second = (hash >> 8) & 0xff;
174 id_hex = hex_encode_talloc(talloc_tos(), id_buf, sizeof(id_buf));
176 if (id_hex == NULL) {
181 result = talloc_asprintf(talloc_tos(), "%s/%2.2X/%2.2X/%s", rootdir,
182 first, second, id_hex);
186 if (result == NULL) {
191 status = create_synthetic_smb_fname(talloc_tos(), result, NULL, NULL,
193 if (!NT_STATUS_IS_OK(status)) {
194 errno = map_errno_from_nt_status(status);
198 if (SMB_VFS_NEXT_STAT(handle, smb_fname_hash) == 0) {
199 struct smb_filename *smb_fname_new = NULL;
202 if (!S_ISDIR(smb_fname_hash->st.st_ex_mode)) {
208 file_is_valid(handle, smb_fname->base_name)) {
213 * Someone has recreated a file under an existing inode
214 * without deleting the streams directory. For now, just move
219 newname = talloc_asprintf(talloc_tos(), "lost-%lu", random());
220 if (newname == NULL) {
225 status = create_synthetic_smb_fname(talloc_tos(), newname,
228 TALLOC_FREE(newname);
229 if (!NT_STATUS_IS_OK(status)) {
230 errno = map_errno_from_nt_status(status);
234 if (SMB_VFS_NEXT_RENAME(handle, smb_fname_hash,
235 smb_fname_new) == -1) {
236 TALLOC_FREE(smb_fname_new);
237 if ((errno == EEXIST) || (errno == ENOTEMPTY)) {
243 TALLOC_FREE(smb_fname_new);
251 if ((SMB_VFS_NEXT_MKDIR(handle, rootdir, 0755) != 0)
252 && (errno != EEXIST)) {
256 tmp = talloc_asprintf(result, "%s/%2.2X", rootdir, first);
262 if ((SMB_VFS_NEXT_MKDIR(handle, tmp, 0755) != 0)
263 && (errno != EEXIST)) {
269 tmp = talloc_asprintf(result, "%s/%2.2X/%2.2X", rootdir, first,
276 if ((SMB_VFS_NEXT_MKDIR(handle, tmp, 0755) != 0)
277 && (errno != EEXIST)) {
283 if ((SMB_VFS_NEXT_MKDIR(handle, result, 0755) != 0)
284 && (errno != EEXIST)) {
288 if (check_valid && !mark_file_valid(handle, smb_fname->base_name)) {
292 TALLOC_FREE(smb_fname_hash);
296 TALLOC_FREE(smb_fname_hash);
301 * Given a stream name, populate smb_fname_out with the actual location of the
304 static NTSTATUS stream_smb_fname(vfs_handle_struct *handle,
305 const struct smb_filename *smb_fname,
306 struct smb_filename **smb_fname_out,
309 char *dirname, *stream_fname;
313 *smb_fname_out = NULL;
315 stype = strchr_m(smb_fname->stream_name + 1, ':');
318 if (strcasecmp_m(stype, ":$DATA") != 0) {
319 return NT_STATUS_INVALID_PARAMETER;
323 dirname = stream_dir(handle, smb_fname, NULL, create_dir);
325 if (dirname == NULL) {
326 status = map_nt_error_from_unix(errno);
330 stream_fname = talloc_asprintf(talloc_tos(), "%s/%s", dirname,
331 smb_fname->stream_name);
333 if (stream_fname == NULL) {
334 status = NT_STATUS_NO_MEMORY;
339 /* Append an explicit stream type if one wasn't specified. */
340 stream_fname = talloc_asprintf(talloc_tos(), "%s:$DATA",
342 if (stream_fname == NULL) {
343 status = NT_STATUS_NO_MEMORY;
347 /* Normalize the stream type to upercase. */
348 if (!strupper_m(strrchr_m(stream_fname, ':') + 1)) {
349 status = NT_STATUS_INVALID_PARAMETER;
354 DEBUG(10, ("stream filename = %s\n", stream_fname));
356 /* Create an smb_filename with stream_name == NULL. */
357 status = create_synthetic_smb_fname(talloc_tos(), stream_fname, NULL,
358 NULL, smb_fname_out);
359 if (!NT_STATUS_IS_OK(status)) {
366 DEBUG(5, ("stream_name failed: %s\n", strerror(errno)));
367 TALLOC_FREE(*smb_fname_out);
371 static NTSTATUS walk_streams(vfs_handle_struct *handle,
372 struct smb_filename *smb_fname_base,
374 bool (*fn)(const char *dirname,
380 DIR *dirhandle = NULL;
381 const char *dirent = NULL;
382 char *talloced = NULL;
384 dirname = stream_dir(handle, smb_fname_base, &smb_fname_base->st,
387 if (dirname == NULL) {
388 if (errno == ENOENT) {
394 return map_nt_error_from_unix(errno);
397 DEBUG(10, ("walk_streams: dirname=%s\n", dirname));
399 dirhandle = SMB_VFS_NEXT_OPENDIR(handle, dirname, NULL, 0);
401 if (dirhandle == NULL) {
402 TALLOC_FREE(dirname);
403 return map_nt_error_from_unix(errno);
406 while ((dirent = vfs_readdirname(handle->conn, dirhandle, NULL,
407 &talloced)) != NULL) {
409 if (ISDOT(dirent) || ISDOTDOT(dirent)) {
410 TALLOC_FREE(talloced);
414 DEBUG(10, ("walk_streams: dirent=%s\n", dirent));
416 if (!fn(dirname, dirent, private_data)) {
417 TALLOC_FREE(talloced);
420 TALLOC_FREE(talloced);
423 SMB_VFS_NEXT_CLOSEDIR(handle, dirhandle);
425 if (pdirname != NULL) {
429 TALLOC_FREE(dirname);
436 * Helper to stat/lstat the base file of an smb_fname. This will actually
437 * fills in the stat struct in smb_filename.
439 static int streams_depot_stat_base(vfs_handle_struct *handle,
440 struct smb_filename *smb_fname,
443 char *tmp_stream_name;
446 tmp_stream_name = smb_fname->stream_name;
447 smb_fname->stream_name = NULL;
449 result = SMB_VFS_NEXT_STAT(handle, smb_fname);
451 result = SMB_VFS_NEXT_LSTAT(handle, smb_fname);
453 smb_fname->stream_name = tmp_stream_name;
457 static int streams_depot_stat(vfs_handle_struct *handle,
458 struct smb_filename *smb_fname)
460 struct smb_filename *smb_fname_stream = NULL;
464 DEBUG(10, ("streams_depot_stat called for [%s]\n",
465 smb_fname_str_dbg(smb_fname)));
467 if (!is_ntfs_stream_smb_fname(smb_fname)) {
468 return SMB_VFS_NEXT_STAT(handle, smb_fname);
471 /* If the default stream is requested, just stat the base file. */
472 if (is_ntfs_default_stream_smb_fname(smb_fname)) {
473 return streams_depot_stat_base(handle, smb_fname, true);
476 /* Stat the actual stream now. */
477 status = stream_smb_fname(handle, smb_fname, &smb_fname_stream,
479 if (!NT_STATUS_IS_OK(status)) {
481 errno = map_errno_from_nt_status(status);
485 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_stream);
487 /* Update the original smb_fname with the stat info. */
488 smb_fname->st = smb_fname_stream->st;
490 TALLOC_FREE(smb_fname_stream);
496 static int streams_depot_lstat(vfs_handle_struct *handle,
497 struct smb_filename *smb_fname)
499 struct smb_filename *smb_fname_stream = NULL;
503 DEBUG(10, ("streams_depot_lstat called for [%s]\n",
504 smb_fname_str_dbg(smb_fname)));
506 if (!is_ntfs_stream_smb_fname(smb_fname)) {
507 return SMB_VFS_NEXT_LSTAT(handle, smb_fname);
510 /* If the default stream is requested, just stat the base file. */
511 if (is_ntfs_default_stream_smb_fname(smb_fname)) {
512 return streams_depot_stat_base(handle, smb_fname, false);
515 /* Stat the actual stream now. */
516 status = stream_smb_fname(handle, smb_fname, &smb_fname_stream,
518 if (!NT_STATUS_IS_OK(status)) {
520 errno = map_errno_from_nt_status(status);
524 ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_stream);
527 TALLOC_FREE(smb_fname_stream);
531 static int streams_depot_open(vfs_handle_struct *handle,
532 struct smb_filename *smb_fname,
533 files_struct *fsp, int flags, mode_t mode)
535 struct smb_filename *smb_fname_stream = NULL;
536 struct smb_filename *smb_fname_base = NULL;
540 if (!is_ntfs_stream_smb_fname(smb_fname)) {
541 return SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
544 /* If the default stream is requested, just open the base file. */
545 if (is_ntfs_default_stream_smb_fname(smb_fname)) {
546 char *tmp_stream_name;
548 tmp_stream_name = smb_fname->stream_name;
549 smb_fname->stream_name = NULL;
550 ret = SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
551 smb_fname->stream_name = tmp_stream_name;
556 /* Ensure the base file still exists. */
557 status = create_synthetic_smb_fname(talloc_tos(),
558 smb_fname->base_name,
561 if (!NT_STATUS_IS_OK(status)) {
563 errno = map_errno_from_nt_status(status);
567 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
572 /* Determine the stream name, and then open it. */
573 status = stream_smb_fname(handle, smb_fname, &smb_fname_stream, true);
574 if (!NT_STATUS_IS_OK(status)) {
576 errno = map_errno_from_nt_status(status);
580 ret = SMB_VFS_NEXT_OPEN(handle, smb_fname_stream, fsp, flags, mode);
583 TALLOC_FREE(smb_fname_stream);
584 TALLOC_FREE(smb_fname_base);
588 static int streams_depot_unlink(vfs_handle_struct *handle,
589 const struct smb_filename *smb_fname)
591 struct smb_filename *smb_fname_base = NULL;
595 DEBUG(10, ("streams_depot_unlink called for %s\n",
596 smb_fname_str_dbg(smb_fname)));
598 /* If there is a valid stream, just unlink the stream and return. */
599 if (is_ntfs_stream_smb_fname(smb_fname) &&
600 !is_ntfs_default_stream_smb_fname(smb_fname)) {
601 struct smb_filename *smb_fname_stream = NULL;
603 status = stream_smb_fname(handle, smb_fname, &smb_fname_stream,
605 if (!NT_STATUS_IS_OK(status)) {
606 errno = map_errno_from_nt_status(status);
610 ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname_stream);
612 TALLOC_FREE(smb_fname_stream);
617 * We potentially need to delete the per-inode streams directory
620 status = create_synthetic_smb_fname(talloc_tos(), smb_fname->base_name,
621 NULL, NULL, &smb_fname_base);
622 if (!NT_STATUS_IS_OK(status)) {
623 errno = map_errno_from_nt_status(status);
627 if (lp_posix_pathnames()) {
628 ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_base);
630 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
634 TALLOC_FREE(smb_fname_base);
638 if (smb_fname_base->st.st_ex_nlink == 1) {
639 char *dirname = stream_dir(handle, smb_fname_base,
640 &smb_fname_base->st, false);
642 if (dirname != NULL) {
643 SMB_VFS_NEXT_RMDIR(handle, dirname);
645 TALLOC_FREE(dirname);
648 ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname);
650 TALLOC_FREE(smb_fname_base);
654 static int streams_depot_rmdir(vfs_handle_struct *handle, const char *path)
656 struct smb_filename *smb_fname_base = NULL;
660 DEBUG(10, ("streams_depot_rmdir called for %s\n", path));
663 * We potentially need to delete the per-inode streams directory
666 status = create_synthetic_smb_fname(talloc_tos(), path,
667 NULL, NULL, &smb_fname_base);
668 if (!NT_STATUS_IS_OK(status)) {
669 errno = map_errno_from_nt_status(status);
673 if (lp_posix_pathnames()) {
674 ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_base);
676 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
680 TALLOC_FREE(smb_fname_base);
684 if (smb_fname_base->st.st_ex_nlink == 2) {
685 char *dirname = stream_dir(handle, smb_fname_base,
686 &smb_fname_base->st, false);
688 if (dirname != NULL) {
689 SMB_VFS_NEXT_RMDIR(handle, dirname);
691 TALLOC_FREE(dirname);
694 ret = SMB_VFS_NEXT_RMDIR(handle, path);
696 TALLOC_FREE(smb_fname_base);
700 static int streams_depot_rename(vfs_handle_struct *handle,
701 const struct smb_filename *smb_fname_src,
702 const struct smb_filename *smb_fname_dst)
704 struct smb_filename *smb_fname_src_stream = NULL;
705 struct smb_filename *smb_fname_dst_stream = NULL;
706 bool src_is_stream, dst_is_stream;
710 DEBUG(10, ("streams_depot_rename called for %s => %s\n",
711 smb_fname_str_dbg(smb_fname_src),
712 smb_fname_str_dbg(smb_fname_dst)));
714 src_is_stream = is_ntfs_stream_smb_fname(smb_fname_src);
715 dst_is_stream = is_ntfs_stream_smb_fname(smb_fname_dst);
717 if (!src_is_stream && !dst_is_stream) {
718 return SMB_VFS_NEXT_RENAME(handle, smb_fname_src,
722 /* for now don't allow renames from or to the default stream */
723 if (is_ntfs_default_stream_smb_fname(smb_fname_src) ||
724 is_ntfs_default_stream_smb_fname(smb_fname_dst)) {
729 status = stream_smb_fname(handle, smb_fname_src, &smb_fname_src_stream,
731 if (!NT_STATUS_IS_OK(status)) {
732 errno = map_errno_from_nt_status(status);
736 status = stream_smb_fname(handle, smb_fname_dst,
737 &smb_fname_dst_stream, false);
738 if (!NT_STATUS_IS_OK(status)) {
739 errno = map_errno_from_nt_status(status);
743 ret = SMB_VFS_NEXT_RENAME(handle, smb_fname_src_stream,
744 smb_fname_dst_stream);
747 TALLOC_FREE(smb_fname_src_stream);
748 TALLOC_FREE(smb_fname_dst_stream);
752 static bool add_one_stream(TALLOC_CTX *mem_ctx, unsigned int *num_streams,
753 struct stream_struct **streams,
754 const char *name, off_t size,
757 struct stream_struct *tmp;
759 tmp = talloc_realloc(mem_ctx, *streams, struct stream_struct,
765 tmp[*num_streams].name = talloc_strdup(tmp, name);
766 if (tmp[*num_streams].name == NULL) {
770 tmp[*num_streams].size = size;
771 tmp[*num_streams].alloc_size = alloc_size;
778 struct streaminfo_state {
780 vfs_handle_struct *handle;
781 unsigned int num_streams;
782 struct stream_struct *streams;
786 static bool collect_one_stream(const char *dirname,
790 struct streaminfo_state *state =
791 (struct streaminfo_state *)private_data;
792 struct smb_filename *smb_fname = NULL;
797 sname = talloc_asprintf(talloc_tos(), "%s/%s", dirname, dirent);
799 state->status = NT_STATUS_NO_MEMORY;
804 status = create_synthetic_smb_fname(talloc_tos(), sname, NULL,
806 if (!NT_STATUS_IS_OK(status)) {
807 state->status = status;
812 if (SMB_VFS_NEXT_STAT(state->handle, smb_fname) == -1) {
813 DEBUG(10, ("Could not stat %s: %s\n", sname,
819 if (!add_one_stream(state->mem_ctx,
820 &state->num_streams, &state->streams,
821 dirent, smb_fname->st.st_ex_size,
822 SMB_VFS_GET_ALLOC_SIZE(state->handle->conn, NULL,
824 state->status = NT_STATUS_NO_MEMORY;
832 TALLOC_FREE(smb_fname);
836 static NTSTATUS streams_depot_streaminfo(vfs_handle_struct *handle,
837 struct files_struct *fsp,
840 unsigned int *pnum_streams,
841 struct stream_struct **pstreams)
843 struct smb_filename *smb_fname_base = NULL;
846 struct streaminfo_state state;
848 status = create_synthetic_smb_fname(talloc_tos(), fname, NULL, NULL,
850 if (!NT_STATUS_IS_OK(status)) {
854 if ((fsp != NULL) && (fsp->fh->fd != -1)) {
855 ret = SMB_VFS_NEXT_FSTAT(handle, fsp, &smb_fname_base->st);
858 if (lp_posix_pathnames()) {
859 ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_base);
861 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
866 status = map_nt_error_from_unix(errno);
870 state.streams = *pstreams;
871 state.num_streams = *pnum_streams;
872 state.mem_ctx = mem_ctx;
873 state.handle = handle;
874 state.status = NT_STATUS_OK;
876 status = walk_streams(handle, smb_fname_base, NULL, collect_one_stream,
879 if (!NT_STATUS_IS_OK(status)) {
880 TALLOC_FREE(state.streams);
884 if (!NT_STATUS_IS_OK(state.status)) {
885 TALLOC_FREE(state.streams);
886 status = state.status;
890 *pnum_streams = state.num_streams;
891 *pstreams = state.streams;
892 status = SMB_VFS_NEXT_STREAMINFO(handle, fsp, fname, mem_ctx, pnum_streams, pstreams);
895 TALLOC_FREE(smb_fname_base);
899 static uint32_t streams_depot_fs_capabilities(struct vfs_handle_struct *handle,
900 enum timestamp_set_resolution *p_ts_res)
902 return SMB_VFS_NEXT_FS_CAPABILITIES(handle, p_ts_res) | FILE_NAMED_STREAMS;
905 static struct vfs_fn_pointers vfs_streams_depot_fns = {
906 .fs_capabilities_fn = streams_depot_fs_capabilities,
907 .open_fn = streams_depot_open,
908 .stat_fn = streams_depot_stat,
909 .lstat_fn = streams_depot_lstat,
910 .unlink_fn = streams_depot_unlink,
911 .rmdir_fn = streams_depot_rmdir,
912 .rename_fn = streams_depot_rename,
913 .streaminfo_fn = streams_depot_streaminfo,
916 NTSTATUS vfs_streams_depot_init(void);
917 NTSTATUS vfs_streams_depot_init(void)
919 return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "streams_depot",
920 &vfs_streams_depot_fns);