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/>.
23 #define DBGC_CLASS DBGC_VFS
26 * Excerpt from a mail from tridge:
28 * Volker, what I'm thinking of is this:
29 * /mount-point/.streams/XX/YY/aaaa.bbbb/namedstream1
30 * /mount-point/.streams/XX/YY/aaaa.bbbb/namedstream2
32 * where XX/YY is a 2 level hash based on the fsid/inode. "aaaa.bbbb"
33 * is the fsid/inode. "namedstreamX" is a file named after the stream
37 static uint32_t hash_fn(DATA_BLOB key)
39 uint32_t value; /* Used to compute the hash value. */
40 uint32_t i; /* Used to cycle through random values. */
42 /* Set the initial value from the key size. */
43 for (value = 0x238F13AF * key.length, i=0; i < key.length; i++)
44 value = (value + (key.data[i] << (i*5 % 24)));
46 return (1103515243 * value + 12345);
50 * With the hashing scheme based on the inode we need to protect against
51 * streams showing up on files with re-used inodes. This can happen if we
52 * create a stream directory from within Samba, and a local process or NFS
53 * client deletes the file without deleting the streams directory. When the
54 * inode is re-used and the stream directory is still around, the streams in
55 * there would be show up as belonging to the new file.
57 * There are several workarounds for this, probably the easiest one is on
58 * systems which have a true birthtime stat element: When the file has a later
59 * birthtime than the streams directory, then we have to recreate the
62 * The other workaround is to somehow mark the file as generated by Samba with
63 * something that a NFS client would not do. The closest one is a special
64 * xattr value being set. On systems which do not support xattrs, it might be
65 * an option to put in a special ACL entry for a non-existing group.
68 static bool file_is_valid(vfs_handle_struct *handle, const char *path,
77 DEBUG(10, ("file_is_valid (%s) called\n", path));
79 if (SMB_VFS_GETXATTR(handle->conn, path, SAMBA_XATTR_MARKER,
80 &buf, sizeof(buf)) != sizeof(buf)) {
81 DEBUG(10, ("GETXATTR failed: %s\n", strerror(errno)));
86 DEBUG(10, ("got wrong buffer content: '%c'\n", buf));
93 static bool mark_file_valid(vfs_handle_struct *handle, const char *path,
103 DEBUG(10, ("marking file %s as valid\n", path));
105 ret = SMB_VFS_SETXATTR(handle->conn, path, SAMBA_XATTR_MARKER,
106 &buf, sizeof(buf), 0);
109 DEBUG(10, ("SETXATTR failed: %s\n", strerror(errno)));
117 * Given an smb_filename, determine the stream directory using the file's
120 static char *stream_dir(vfs_handle_struct *handle,
121 const struct smb_filename *smb_fname,
122 const SMB_STRUCT_STAT *base_sbuf, bool create_it)
125 struct smb_filename *smb_fname_hash = NULL;
127 SMB_STRUCT_STAT base_sbuf_tmp;
128 uint8_t first, second;
137 check_valid = lp_parm_bool(SNUM(handle->conn),
138 "streams_depot", "check_valid", true);
140 tmp = talloc_asprintf(talloc_tos(), "%s/.streams", handle->conn->connectpath);
147 rootdir = lp_parm_const_string(
148 SNUM(handle->conn), "streams_depot", "directory",
151 /* Stat the base file if it hasn't already been done. */
152 if (base_sbuf == NULL) {
153 struct smb_filename *smb_fname_base = NULL;
155 status = create_synthetic_smb_fname(talloc_tos(),
156 smb_fname->base_name,
159 if (!NT_STATUS_IS_OK(status)) {
160 errno = map_errno_from_nt_status(status);
163 if (SMB_VFS_NEXT_STAT(handle, smb_fname_base) == -1) {
164 TALLOC_FREE(smb_fname_base);
167 base_sbuf_tmp = smb_fname_base->st;
168 TALLOC_FREE(smb_fname_base);
170 base_sbuf_tmp = *base_sbuf;
173 id = SMB_VFS_FILE_ID_CREATE(handle->conn, &base_sbuf_tmp);
175 push_file_id_16((char *)id_buf, &id);
177 hash = hash_fn(data_blob_const(id_buf, sizeof(id_buf)));
180 second = (hash >> 8) & 0xff;
182 id_hex = hex_encode_talloc(talloc_tos(), id_buf, sizeof(id_buf));
184 if (id_hex == NULL) {
189 result = talloc_asprintf(talloc_tos(), "%s/%2.2X/%2.2X/%s", rootdir,
190 first, second, id_hex);
194 if (result == NULL) {
199 status = create_synthetic_smb_fname(talloc_tos(), result, NULL, NULL,
201 if (!NT_STATUS_IS_OK(status)) {
202 errno = map_errno_from_nt_status(status);
206 if (SMB_VFS_NEXT_STAT(handle, smb_fname_hash) == 0) {
207 struct smb_filename *smb_fname_new = NULL;
210 if (!S_ISDIR(smb_fname_hash->st.st_ex_mode)) {
215 if (file_is_valid(handle, smb_fname->base_name, check_valid)) {
220 * Someone has recreated a file under an existing inode
221 * without deleting the streams directory. For now, just move
226 newname = talloc_asprintf(talloc_tos(), "lost-%lu", random());
227 if (newname == NULL) {
232 status = create_synthetic_smb_fname(talloc_tos(), newname,
235 TALLOC_FREE(newname);
236 if (!NT_STATUS_IS_OK(status)) {
237 errno = map_errno_from_nt_status(status);
241 if (SMB_VFS_NEXT_RENAME(handle, smb_fname_hash,
242 smb_fname_new) == -1) {
243 TALLOC_FREE(smb_fname_new);
244 if ((errno == EEXIST) || (errno == ENOTEMPTY)) {
250 TALLOC_FREE(smb_fname_new);
258 if ((SMB_VFS_NEXT_MKDIR(handle, rootdir, 0755) != 0)
259 && (errno != EEXIST)) {
263 tmp = talloc_asprintf(result, "%s/%2.2X", rootdir, first);
269 if ((SMB_VFS_NEXT_MKDIR(handle, tmp, 0755) != 0)
270 && (errno != EEXIST)) {
276 tmp = talloc_asprintf(result, "%s/%2.2X/%2.2X", rootdir, first,
283 if ((SMB_VFS_NEXT_MKDIR(handle, tmp, 0755) != 0)
284 && (errno != EEXIST)) {
290 if ((SMB_VFS_NEXT_MKDIR(handle, result, 0755) != 0)
291 && (errno != EEXIST)) {
295 if (!mark_file_valid(handle, smb_fname->base_name, check_valid)) {
299 TALLOC_FREE(smb_fname_hash);
303 TALLOC_FREE(smb_fname_hash);
308 * Given a stream name, populate smb_fname_out with the actual location of the
311 static NTSTATUS stream_smb_fname(vfs_handle_struct *handle,
312 const struct smb_filename *smb_fname,
313 struct smb_filename **smb_fname_out,
316 char *dirname, *stream_fname;
320 *smb_fname_out = NULL;
322 stype = strchr_m(smb_fname->stream_name + 1, ':');
325 if (StrCaseCmp(stype, ":$DATA") != 0) {
326 return NT_STATUS_INVALID_PARAMETER;
330 dirname = stream_dir(handle, smb_fname, NULL, create_dir);
332 if (dirname == NULL) {
333 status = map_nt_error_from_unix(errno);
337 stream_fname = talloc_asprintf(talloc_tos(), "%s/%s", dirname,
338 smb_fname->stream_name);
340 if (stream_fname == NULL) {
341 status = NT_STATUS_NO_MEMORY;
346 /* Append an explicit stream type if one wasn't specified. */
347 stream_fname = talloc_asprintf(talloc_tos(), "%s:$DATA",
349 if (stream_fname == NULL) {
350 status = NT_STATUS_NO_MEMORY;
354 /* Normalize the stream type to upercase. */
355 strupper_m(strrchr_m(stream_fname, ':') + 1);
358 DEBUG(10, ("stream filename = %s\n", stream_fname));
360 /* Create an smb_filename with stream_name == NULL. */
361 status = create_synthetic_smb_fname(talloc_tos(), stream_fname, NULL,
362 NULL, smb_fname_out);
363 if (!NT_STATUS_IS_OK(status)) {
370 DEBUG(5, ("stream_name failed: %s\n", strerror(errno)));
371 TALLOC_FREE(*smb_fname_out);
375 static NTSTATUS walk_streams(vfs_handle_struct *handle,
376 struct smb_filename *smb_fname_base,
378 bool (*fn)(const char *dirname,
384 SMB_STRUCT_DIR *dirhandle = NULL;
387 dirname = stream_dir(handle, smb_fname_base, &smb_fname_base->st,
390 if (dirname == NULL) {
391 if (errno == ENOENT) {
397 return map_nt_error_from_unix(errno);
400 DEBUG(10, ("walk_streams: dirname=%s\n", dirname));
402 dirhandle = SMB_VFS_NEXT_OPENDIR(handle, dirname, NULL, 0);
404 if (dirhandle == NULL) {
405 TALLOC_FREE(dirname);
406 return map_nt_error_from_unix(errno);
409 while ((dirent = vfs_readdirname(handle->conn, dirhandle, NULL)) != NULL) {
411 if (ISDOT(dirent) || ISDOTDOT(dirent)) {
416 DEBUG(10, ("walk_streams: dirent=%s\n", dirent));
418 if (!fn(dirname, dirent, private_data)) {
425 SMB_VFS_NEXT_CLOSEDIR(handle, dirhandle);
427 if (pdirname != NULL) {
431 TALLOC_FREE(dirname);
438 * Helper to stat/lstat the base file of an smb_fname. This will actually
439 * fills in the stat struct in smb_filename.
441 static int streams_depot_stat_base(vfs_handle_struct *handle,
442 struct smb_filename *smb_fname,
445 char *tmp_stream_name;
448 tmp_stream_name = smb_fname->stream_name;
449 smb_fname->stream_name = NULL;
451 result = SMB_VFS_NEXT_STAT(handle, smb_fname);
453 result = SMB_VFS_NEXT_LSTAT(handle, smb_fname);
455 smb_fname->stream_name = tmp_stream_name;
459 static int streams_depot_stat(vfs_handle_struct *handle,
460 struct smb_filename *smb_fname)
462 struct smb_filename *smb_fname_stream = NULL;
466 DEBUG(10, ("streams_depot_stat called for [%s]\n",
467 smb_fname_str_dbg(smb_fname)));
469 if (!is_ntfs_stream_smb_fname(smb_fname)) {
470 return SMB_VFS_NEXT_STAT(handle, smb_fname);
473 /* If the default stream is requested, just stat the base file. */
474 if (is_ntfs_default_stream_smb_fname(smb_fname)) {
475 return streams_depot_stat_base(handle, smb_fname, true);
478 /* Stat the actual stream now. */
479 status = stream_smb_fname(handle, smb_fname, &smb_fname_stream,
481 if (!NT_STATUS_IS_OK(status)) {
483 errno = map_errno_from_nt_status(status);
487 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_stream);
489 /* Update the original smb_fname with the stat info. */
490 smb_fname->st = smb_fname_stream->st;
492 TALLOC_FREE(smb_fname_stream);
498 static int streams_depot_lstat(vfs_handle_struct *handle,
499 struct smb_filename *smb_fname)
501 struct smb_filename *smb_fname_stream = NULL;
505 DEBUG(10, ("streams_depot_lstat called for [%s]\n",
506 smb_fname_str_dbg(smb_fname)));
508 if (!is_ntfs_stream_smb_fname(smb_fname)) {
509 return SMB_VFS_NEXT_LSTAT(handle, smb_fname);
512 /* If the default stream is requested, just stat the base file. */
513 if (is_ntfs_default_stream_smb_fname(smb_fname)) {
514 return streams_depot_stat_base(handle, smb_fname, false);
517 /* Stat the actual stream now. */
518 status = stream_smb_fname(handle, smb_fname, &smb_fname_stream,
520 if (!NT_STATUS_IS_OK(status)) {
522 errno = map_errno_from_nt_status(status);
526 ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_stream);
529 TALLOC_FREE(smb_fname_stream);
533 static int streams_depot_open(vfs_handle_struct *handle,
534 struct smb_filename *smb_fname,
535 files_struct *fsp, int flags, mode_t mode)
537 struct smb_filename *smb_fname_stream = NULL;
538 struct smb_filename *smb_fname_base = NULL;
542 if (!is_ntfs_stream_smb_fname(smb_fname)) {
543 return SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
546 /* If the default stream is requested, just open the base file. */
547 if (is_ntfs_default_stream_smb_fname(smb_fname)) {
548 char *tmp_stream_name;
550 tmp_stream_name = smb_fname->stream_name;
551 smb_fname->stream_name = NULL;
552 ret = SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
553 smb_fname->stream_name = tmp_stream_name;
558 /* Ensure the base file still exists. */
559 status = create_synthetic_smb_fname(talloc_tos(),
560 smb_fname->base_name,
563 if (!NT_STATUS_IS_OK(status)) {
565 errno = map_errno_from_nt_status(status);
569 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
574 /* Determine the stream name, and then open it. */
575 status = stream_smb_fname(handle, smb_fname, &smb_fname_stream, true);
576 if (!NT_STATUS_IS_OK(status)) {
578 errno = map_errno_from_nt_status(status);
582 ret = SMB_VFS_NEXT_OPEN(handle, smb_fname_stream, fsp, flags, mode);
585 TALLOC_FREE(smb_fname_stream);
586 TALLOC_FREE(smb_fname_base);
590 static int streams_depot_unlink(vfs_handle_struct *handle,
591 const struct smb_filename *smb_fname)
593 struct smb_filename *smb_fname_base = NULL;
597 DEBUG(10, ("streams_depot_unlink called for %s\n",
598 smb_fname_str_dbg(smb_fname)));
600 /* If there is a valid stream, just unlink the stream and return. */
601 if (is_ntfs_stream_smb_fname(smb_fname) &&
602 !is_ntfs_default_stream_smb_fname(smb_fname)) {
603 struct smb_filename *smb_fname_stream = NULL;
605 status = stream_smb_fname(handle, smb_fname, &smb_fname_stream,
607 if (!NT_STATUS_IS_OK(status)) {
608 errno = map_errno_from_nt_status(status);
612 ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname_stream);
614 TALLOC_FREE(smb_fname_stream);
619 * We potentially need to delete the per-inode streams directory
622 status = create_synthetic_smb_fname(talloc_tos(), smb_fname->base_name,
623 NULL, NULL, &smb_fname_base);
624 if (!NT_STATUS_IS_OK(status)) {
625 errno = map_errno_from_nt_status(status);
629 if (lp_posix_pathnames()) {
630 ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_base);
632 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
636 TALLOC_FREE(smb_fname_base);
640 if (smb_fname_base->st.st_ex_nlink == 1) {
641 char *dirname = stream_dir(handle, smb_fname_base,
642 &smb_fname_base->st, false);
644 if (dirname != NULL) {
645 SMB_VFS_NEXT_RMDIR(handle, dirname);
647 TALLOC_FREE(dirname);
650 ret = SMB_VFS_NEXT_UNLINK(handle, smb_fname);
652 TALLOC_FREE(smb_fname_base);
656 static int streams_depot_rename(vfs_handle_struct *handle,
657 const struct smb_filename *smb_fname_src,
658 const struct smb_filename *smb_fname_dst)
660 struct smb_filename *smb_fname_src_stream = NULL;
661 struct smb_filename *smb_fname_dst_stream = NULL;
662 struct smb_filename *smb_fname_dst_mod = NULL;
663 bool src_is_stream, dst_is_stream;
667 DEBUG(10, ("streams_depot_rename called for %s => %s\n",
668 smb_fname_str_dbg(smb_fname_src),
669 smb_fname_str_dbg(smb_fname_dst)));
671 src_is_stream = is_ntfs_stream_smb_fname(smb_fname_src);
672 dst_is_stream = is_ntfs_stream_smb_fname(smb_fname_dst);
674 if (!src_is_stream && !dst_is_stream) {
675 return SMB_VFS_NEXT_RENAME(handle, smb_fname_src,
679 /* for now don't allow renames from or to the default stream */
680 if (is_ntfs_default_stream_smb_fname(smb_fname_src) ||
681 is_ntfs_default_stream_smb_fname(smb_fname_dst)) {
686 status = stream_smb_fname(handle, smb_fname_src, &smb_fname_src_stream,
688 if (!NT_STATUS_IS_OK(status)) {
689 errno = map_errno_from_nt_status(status);
694 * Handle passing in a stream name without the base file. This is
695 * exercised by the NTRENAME streams rename path.
697 if (StrCaseCmp(smb_fname_dst->base_name, "./") == 0) {
698 status = create_synthetic_smb_fname(talloc_tos(),
699 smb_fname_src->base_name,
700 smb_fname_dst->stream_name,
701 NULL, &smb_fname_dst_mod);
702 if (!NT_STATUS_IS_OK(status)) {
703 errno = map_errno_from_nt_status(status);
708 status = stream_smb_fname(handle, (smb_fname_dst_mod ?
709 smb_fname_dst_mod : smb_fname_dst),
710 &smb_fname_dst_stream, false);
711 if (!NT_STATUS_IS_OK(status)) {
712 errno = map_errno_from_nt_status(status);
716 ret = SMB_VFS_NEXT_RENAME(handle, smb_fname_src_stream,
717 smb_fname_dst_stream);
720 TALLOC_FREE(smb_fname_src_stream);
721 TALLOC_FREE(smb_fname_dst_stream);
722 TALLOC_FREE(smb_fname_dst_mod);
726 static bool add_one_stream(TALLOC_CTX *mem_ctx, unsigned int *num_streams,
727 struct stream_struct **streams,
728 const char *name, SMB_OFF_T size,
729 SMB_OFF_T alloc_size)
731 struct stream_struct *tmp;
733 tmp = TALLOC_REALLOC_ARRAY(mem_ctx, *streams, struct stream_struct,
739 tmp[*num_streams].name = talloc_strdup(tmp, name);
740 if (tmp[*num_streams].name == NULL) {
744 tmp[*num_streams].size = size;
745 tmp[*num_streams].alloc_size = alloc_size;
752 struct streaminfo_state {
754 vfs_handle_struct *handle;
755 unsigned int num_streams;
756 struct stream_struct *streams;
760 static bool collect_one_stream(const char *dirname,
764 struct streaminfo_state *state =
765 (struct streaminfo_state *)private_data;
766 struct smb_filename *smb_fname = NULL;
771 sname = talloc_asprintf(talloc_tos(), "%s/%s", dirname, dirent);
773 state->status = NT_STATUS_NO_MEMORY;
778 status = create_synthetic_smb_fname(talloc_tos(), sname, NULL,
780 if (!NT_STATUS_IS_OK(status)) {
781 state->status = status;
786 if (SMB_VFS_NEXT_STAT(state->handle, smb_fname) == -1) {
787 DEBUG(10, ("Could not stat %s: %s\n", sname,
793 if (!add_one_stream(state->mem_ctx,
794 &state->num_streams, &state->streams,
795 dirent, smb_fname->st.st_ex_size,
796 SMB_VFS_GET_ALLOC_SIZE(state->handle->conn, NULL,
798 state->status = NT_STATUS_NO_MEMORY;
806 TALLOC_FREE(smb_fname);
810 static NTSTATUS streams_depot_streaminfo(vfs_handle_struct *handle,
811 struct files_struct *fsp,
814 unsigned int *pnum_streams,
815 struct stream_struct **pstreams)
817 struct smb_filename *smb_fname_base = NULL;
820 struct streaminfo_state state;
822 status = create_synthetic_smb_fname(talloc_tos(), fname, NULL, NULL,
824 if (!NT_STATUS_IS_OK(status)) {
828 if ((fsp != NULL) && (fsp->fh->fd != -1)) {
829 ret = SMB_VFS_NEXT_FSTAT(handle, fsp, &smb_fname_base->st);
832 if (lp_posix_pathnames()) {
833 ret = SMB_VFS_NEXT_LSTAT(handle, smb_fname_base);
835 ret = SMB_VFS_NEXT_STAT(handle, smb_fname_base);
840 status = map_nt_error_from_unix(errno);
844 state.streams = NULL;
845 state.num_streams = 0;
847 if (!S_ISDIR(smb_fname_base->st.st_ex_mode)) {
848 if (!add_one_stream(mem_ctx,
849 &state.num_streams, &state.streams,
850 "::$DATA", smb_fname_base->st.st_ex_size,
851 SMB_VFS_GET_ALLOC_SIZE(handle->conn, fsp,
852 &smb_fname_base->st))) {
853 status = NT_STATUS_NO_MEMORY;
858 state.mem_ctx = mem_ctx;
859 state.handle = handle;
860 state.status = NT_STATUS_OK;
862 status = walk_streams(handle, smb_fname_base, NULL, collect_one_stream,
865 if (!NT_STATUS_IS_OK(status)) {
866 TALLOC_FREE(state.streams);
870 if (!NT_STATUS_IS_OK(state.status)) {
871 TALLOC_FREE(state.streams);
872 status = state.status;
876 *pnum_streams = state.num_streams;
877 *pstreams = state.streams;
878 status = NT_STATUS_OK;
881 TALLOC_FREE(smb_fname_base);
885 static uint32_t streams_depot_fs_capabilities(struct vfs_handle_struct *handle,
886 enum timestamp_set_resolution *p_ts_res)
888 return SMB_VFS_NEXT_FS_CAPABILITIES(handle, p_ts_res) | FILE_NAMED_STREAMS;
891 static struct vfs_fn_pointers vfs_streams_depot_fns = {
892 .fs_capabilities = streams_depot_fs_capabilities,
893 .open = streams_depot_open,
894 .stat = streams_depot_stat,
895 .lstat = streams_depot_lstat,
896 .unlink = streams_depot_unlink,
897 .rename = streams_depot_rename,
898 .streaminfo = streams_depot_streaminfo,
901 NTSTATUS vfs_streams_depot_init(void);
902 NTSTATUS vfs_streams_depot_init(void)
904 return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "streams_depot",
905 &vfs_streams_depot_fns);