2 * VFS module to disallow writes for older files
4 * Copyright (C) 2013, Volker Lendecke
5 * Copyright (C) 2023-2024, Björn Jacke
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 3 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, see <http://www.gnu.org/licenses/>.
22 #include "smbd/smbd.h"
23 #include "system/filesys.h"
24 #include "libcli/security/security.h"
26 struct worm_config_data {
29 static const uint32_t write_access_flags = FILE_WRITE_DATA | FILE_APPEND_DATA |
30 FILE_WRITE_ATTRIBUTES |
31 DELETE_ACCESS | WRITE_DAC_ACCESS |
32 WRITE_OWNER_ACCESS | FILE_WRITE_EA;
34 static int vfs_worm_connect(struct vfs_handle_struct *handle,
35 const char *service, const char *user)
37 struct worm_config_data *config = NULL;
40 ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
45 if (IS_IPC(handle->conn) || IS_PRINT(handle->conn)) {
49 config = talloc_zero(handle->conn, struct worm_config_data);
51 DBG_ERR("talloc_zero() failed\n");
55 config->grace_period = lp_parm_int(SNUM(handle->conn), "worm",
56 "grace_period", 3600);
58 SMB_VFS_HANDLE_SET_DATA(handle, config,
59 NULL, struct worm_config_data,
65 static bool is_readonly(vfs_handle_struct *handle,
66 const struct smb_filename *smb_fname)
69 struct worm_config_data *config = NULL;
71 SMB_VFS_HANDLE_GET_DATA(handle,
73 struct worm_config_data,
76 if (!VALID_STAT(smb_fname->st)) {
80 age = timespec_elapsed(&smb_fname->st.st_ex_ctime);
82 if (age > config->grace_period) {
89 static bool fsp_is_readonly(vfs_handle_struct *handle, files_struct *fsp)
92 struct worm_config_data *config = NULL;
94 SMB_VFS_HANDLE_GET_DATA(handle,
96 struct worm_config_data,
99 if (!VALID_STAT(fsp->fsp_name->st)) {
103 age = timespec_elapsed(&fsp->fsp_name->st.st_ex_ctime);
105 if (age > config->grace_period) {
113 static NTSTATUS vfs_worm_create_file(vfs_handle_struct *handle,
114 struct smb_request *req,
115 struct files_struct *dirfsp,
116 struct smb_filename *smb_fname,
117 uint32_t access_mask,
118 uint32_t share_access,
119 uint32_t create_disposition,
120 uint32_t create_options,
121 uint32_t file_attributes,
122 uint32_t oplock_request,
123 const struct smb2_lease *lease,
124 uint64_t allocation_size,
125 uint32_t private_flags,
126 struct security_descriptor *sd,
127 struct ea_list *ea_list,
128 files_struct **result,
130 const struct smb2_create_blobs *in_context_blobs,
131 struct smb2_create_blobs *out_context_blobs)
136 readonly = is_readonly(handle, smb_fname);
138 if (readonly && (access_mask & write_access_flags)) {
139 return NT_STATUS_ACCESS_DENIED;
142 status = SMB_VFS_NEXT_CREATE_FILE(
143 handle, req, dirfsp, smb_fname, access_mask,
144 share_access, create_disposition, create_options,
145 file_attributes, oplock_request, lease, allocation_size,
146 private_flags, sd, ea_list, result, pinfo,
147 in_context_blobs, out_context_blobs);
148 if (!NT_STATUS_IS_OK(status)) {
153 * Access via MAXIMUM_ALLOWED_ACCESS?
155 if (readonly && ((*result)->access_mask & write_access_flags)) {
156 close_file_free(req, result, NORMAL_CLOSE);
157 return NT_STATUS_ACCESS_DENIED;
162 static int vfs_worm_openat(vfs_handle_struct *handle,
163 const struct files_struct *dirfsp,
164 const struct smb_filename *smb_fname,
166 const struct vfs_open_how *how)
168 if (is_readonly(handle, smb_fname) &&
169 (fsp->access_mask & write_access_flags)) {
174 return SMB_VFS_NEXT_OPENAT(handle, dirfsp, smb_fname, fsp, how);
177 static int vfs_worm_fntimes(vfs_handle_struct *handle,
179 struct smb_file_time *ft)
181 if (fsp_is_readonly(handle, fsp)) {
186 return SMB_VFS_NEXT_FNTIMES(handle, fsp, ft);
189 static int vfs_worm_fchmod(vfs_handle_struct *handle,
193 if (fsp_is_readonly(handle, fsp)) {
198 return SMB_VFS_NEXT_FCHMOD(handle, fsp, mode);
201 static int vfs_worm_fchown(vfs_handle_struct *handle,
206 if (fsp_is_readonly(handle, fsp)) {
211 return SMB_VFS_NEXT_FCHOWN(handle, fsp, uid, gid);
214 static int vfs_worm_renameat(vfs_handle_struct *handle,
215 files_struct *srcfsp,
216 const struct smb_filename *smb_fname_src,
217 files_struct *dstfsp,
218 const struct smb_filename *smb_fname_dst)
220 if (is_readonly(handle, smb_fname_src)) {
225 return SMB_VFS_NEXT_RENAMEAT(
226 handle, srcfsp, smb_fname_src, dstfsp, smb_fname_dst);
229 static int vfs_worm_fsetxattr(struct vfs_handle_struct *handle,
230 struct files_struct *fsp,
236 if (fsp_is_readonly(handle, fsp)) {
241 return SMB_VFS_NEXT_FSETXATTR(handle, fsp, name, value, size, flags);
244 static int vfs_worm_fremotexattr(struct vfs_handle_struct *handle,
245 struct files_struct *fsp,
248 if (fsp_is_readonly(handle, fsp)) {
253 return SMB_VFS_NEXT_FREMOVEXATTR(handle, fsp, name);
256 static int vfs_worm_unlinkat(vfs_handle_struct *handle,
257 struct files_struct *dirfsp,
258 const struct smb_filename *smb_fname,
261 struct smb_filename *full_fname = NULL;
264 full_fname = full_path_from_dirfsp_atname(talloc_tos(),
267 if (full_fname == NULL) {
271 readonly = is_readonly(handle, full_fname);
273 TALLOC_FREE(full_fname);
280 return SMB_VFS_NEXT_UNLINKAT(handle, dirfsp, smb_fname, flags);
283 static NTSTATUS vfs_worm_fset_dos_attributes(struct vfs_handle_struct *handle,
284 struct files_struct *fsp,
287 if (fsp_is_readonly(handle, fsp)) {
288 return NT_STATUS_ACCESS_DENIED;
291 return SMB_VFS_NEXT_FSET_DOS_ATTRIBUTES(handle, fsp, dosmode);
294 static NTSTATUS vfs_worm_fset_nt_acl(vfs_handle_struct *handle,
296 uint32_t security_info_sent,
297 const struct security_descriptor *psd)
299 if (fsp_is_readonly(handle, fsp)) {
300 return NT_STATUS_ACCESS_DENIED;
303 return SMB_VFS_NEXT_FSET_NT_ACL(handle, fsp, security_info_sent, psd);
306 static int vfs_worm_sys_acl_set_fd(vfs_handle_struct *handle,
307 struct files_struct *fsp,
311 if (fsp_is_readonly(handle, fsp)) {
316 return SMB_VFS_NEXT_SYS_ACL_SET_FD(handle, fsp, type, theacl);
319 static int vfs_worm_sys_acl_delete_def_fd(vfs_handle_struct *handle,
320 struct files_struct *fsp)
322 if (fsp_is_readonly(handle, fsp)) {
327 return SMB_VFS_NEXT_SYS_ACL_DELETE_DEF_FD(handle, fsp);
330 static struct vfs_fn_pointers vfs_worm_fns = {
331 .connect_fn = vfs_worm_connect,
332 .create_file_fn = vfs_worm_create_file,
333 .openat_fn = vfs_worm_openat,
334 .fntimes_fn = vfs_worm_fntimes,
335 .fchmod_fn = vfs_worm_fchmod,
336 .fchown_fn = vfs_worm_fchown,
337 .renameat_fn = vfs_worm_renameat,
338 .fsetxattr_fn = vfs_worm_fsetxattr,
339 .fremovexattr_fn = vfs_worm_fremotexattr,
340 .unlinkat_fn = vfs_worm_unlinkat,
341 .fset_dos_attributes_fn = vfs_worm_fset_dos_attributes,
342 .fset_nt_acl_fn = vfs_worm_fset_nt_acl,
343 .sys_acl_set_fd_fn = vfs_worm_sys_acl_set_fd,
344 .sys_acl_delete_def_fd_fn = vfs_worm_sys_acl_delete_def_fd,
348 NTSTATUS vfs_worm_init(TALLOC_CTX *ctx)
352 ret = smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "worm",
354 if (!NT_STATUS_IS_OK(ret)) {