1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3 *
4 * Copyright (c) International Business Machines Corp., 2003, 2007
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 */
8
9 #include <linux/fs.h>
10 #include <linux/posix_acl_xattr.h>
11 #include <linux/slab.h>
12 #include <linux/xattr.h>
13 #include "cifsfs.h"
14 #include "cifspdu.h"
15 #include "cifsglob.h"
16 #include "cifsproto.h"
17 #include "cifs_debug.h"
18 #include "cifs_fs_sb.h"
19 #include "cifs_unicode.h"
20 #include "cifs_ioctl.h"
21
22 #define MAX_EA_VALUE_SIZE CIFSMaxBufSize
23 #define CIFS_XATTR_CIFS_ACL "system.cifs_acl" /* DACL only */
24 #define CIFS_XATTR_CIFS_NTSD "system.cifs_ntsd" /* owner plus DACL */
25 #define CIFS_XATTR_CIFS_NTSD_FULL "system.cifs_ntsd_full" /* owner/DACL/SACL */
26 #define CIFS_XATTR_ATTRIB "cifs.dosattrib" /* full name: user.cifs.dosattrib */
27 #define CIFS_XATTR_CREATETIME "cifs.creationtime" /* user.cifs.creationtime */
28 /*
29 * Although these three are just aliases for the above, need to move away from
30 * confusing users and using the 20+ year old term 'cifs' when it is no longer
31 * secure, replaced by SMB2 (then even more highly secure SMB3) many years ago
32 */
33 #define SMB3_XATTR_CIFS_ACL "system.smb3_acl" /* DACL only */
34 #define SMB3_XATTR_CIFS_NTSD "system.smb3_ntsd" /* owner plus DACL */
35 #define SMB3_XATTR_CIFS_NTSD_FULL "system.smb3_ntsd_full" /* owner/DACL/SACL */
36 #define SMB3_XATTR_ATTRIB "smb3.dosattrib" /* full name: user.smb3.dosattrib */
37 #define SMB3_XATTR_CREATETIME "smb3.creationtime" /* user.smb3.creationtime */
38 /* BB need to add server (Samba e.g) support for security and trusted prefix */
39
40 enum { XATTR_USER, XATTR_CIFS_ACL, XATTR_ACL_ACCESS, XATTR_ACL_DEFAULT,
41 XATTR_CIFS_NTSD, XATTR_CIFS_NTSD_FULL };
42
cifs_attrib_set(unsigned int xid,struct cifs_tcon * pTcon,struct inode * inode,const char * full_path,const void * value,size_t size)43 static int cifs_attrib_set(unsigned int xid, struct cifs_tcon *pTcon,
44 struct inode *inode, const char *full_path,
45 const void *value, size_t size)
46 {
47 ssize_t rc = -EOPNOTSUPP;
48 __u32 *pattrib = (__u32 *)value;
49 __u32 attrib;
50 FILE_BASIC_INFO info_buf;
51
52 if ((value == NULL) || (size != sizeof(__u32)))
53 return -ERANGE;
54
55 memset(&info_buf, 0, sizeof(info_buf));
56 attrib = *pattrib;
57 info_buf.Attributes = cpu_to_le32(attrib);
58 if (pTcon->ses->server->ops->set_file_info)
59 rc = pTcon->ses->server->ops->set_file_info(inode, full_path,
60 &info_buf, xid);
61 if (rc == 0)
62 CIFS_I(inode)->cifsAttrs = attrib;
63
64 return rc;
65 }
66
cifs_creation_time_set(unsigned int xid,struct cifs_tcon * pTcon,struct inode * inode,const char * full_path,const void * value,size_t size)67 static int cifs_creation_time_set(unsigned int xid, struct cifs_tcon *pTcon,
68 struct inode *inode, const char *full_path,
69 const void *value, size_t size)
70 {
71 ssize_t rc = -EOPNOTSUPP;
72 __u64 *pcreation_time = (__u64 *)value;
73 __u64 creation_time;
74 FILE_BASIC_INFO info_buf;
75
76 if ((value == NULL) || (size != sizeof(__u64)))
77 return -ERANGE;
78
79 memset(&info_buf, 0, sizeof(info_buf));
80 creation_time = *pcreation_time;
81 info_buf.CreationTime = cpu_to_le64(creation_time);
82 if (pTcon->ses->server->ops->set_file_info)
83 rc = pTcon->ses->server->ops->set_file_info(inode, full_path,
84 &info_buf, xid);
85 if (rc == 0)
86 CIFS_I(inode)->createtime = creation_time;
87
88 return rc;
89 }
90
cifs_xattr_set(const struct xattr_handler * handler,struct mnt_idmap * idmap,struct dentry * dentry,struct inode * inode,const char * name,const void * value,size_t size,int flags)91 static int cifs_xattr_set(const struct xattr_handler *handler,
92 struct mnt_idmap *idmap,
93 struct dentry *dentry, struct inode *inode,
94 const char *name, const void *value,
95 size_t size, int flags)
96 {
97 int rc = -EOPNOTSUPP;
98 unsigned int xid;
99 struct super_block *sb = dentry->d_sb;
100 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
101 struct tcon_link *tlink;
102 struct cifs_tcon *pTcon;
103 const char *full_path;
104 void *page;
105
106 tlink = cifs_sb_tlink(cifs_sb);
107 if (IS_ERR(tlink))
108 return PTR_ERR(tlink);
109 pTcon = tlink_tcon(tlink);
110
111 xid = get_xid();
112 page = alloc_dentry_path();
113
114 full_path = build_path_from_dentry(dentry, page);
115 if (IS_ERR(full_path)) {
116 rc = PTR_ERR(full_path);
117 goto out;
118 }
119 /* return dos attributes as pseudo xattr */
120 /* return alt name if available as pseudo attr */
121
122 /* if proc/fs/cifs/streamstoxattr is set then
123 search server for EAs or streams to
124 returns as xattrs */
125 if (size > MAX_EA_VALUE_SIZE) {
126 cifs_dbg(FYI, "size of EA value too large\n");
127 rc = -EOPNOTSUPP;
128 goto out;
129 }
130
131 switch (handler->flags) {
132 case XATTR_USER:
133 cifs_dbg(FYI, "%s:setting user xattr %s\n", __func__, name);
134 if ((strcmp(name, CIFS_XATTR_ATTRIB) == 0) ||
135 (strcmp(name, SMB3_XATTR_ATTRIB) == 0)) {
136 rc = cifs_attrib_set(xid, pTcon, inode, full_path,
137 value, size);
138 if (rc == 0) /* force revalidate of the inode */
139 CIFS_I(inode)->time = 0;
140 break;
141 } else if ((strcmp(name, CIFS_XATTR_CREATETIME) == 0) ||
142 (strcmp(name, SMB3_XATTR_CREATETIME) == 0)) {
143 rc = cifs_creation_time_set(xid, pTcon, inode,
144 full_path, value, size);
145 if (rc == 0) /* force revalidate of the inode */
146 CIFS_I(inode)->time = 0;
147 break;
148 }
149
150 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
151 goto out;
152
153 if (pTcon->ses->server->ops->set_EA) {
154 rc = pTcon->ses->server->ops->set_EA(xid, pTcon,
155 full_path, name, value, (__u16)size,
156 cifs_sb->local_nls, cifs_sb);
157 if (rc == 0)
158 inode_set_ctime_current(inode);
159 }
160 break;
161
162 case XATTR_CIFS_ACL:
163 case XATTR_CIFS_NTSD:
164 case XATTR_CIFS_NTSD_FULL: {
165 struct cifs_ntsd *pacl;
166
167 if (!value)
168 goto out;
169 pacl = kmalloc(size, GFP_KERNEL);
170 if (!pacl) {
171 rc = -ENOMEM;
172 } else {
173 memcpy(pacl, value, size);
174 if (pTcon->ses->server->ops->set_acl) {
175 int aclflags = 0;
176 rc = 0;
177
178 switch (handler->flags) {
179 case XATTR_CIFS_NTSD_FULL:
180 aclflags = (CIFS_ACL_OWNER |
181 CIFS_ACL_GROUP |
182 CIFS_ACL_DACL |
183 CIFS_ACL_SACL);
184 break;
185 case XATTR_CIFS_NTSD:
186 aclflags = (CIFS_ACL_OWNER |
187 CIFS_ACL_GROUP |
188 CIFS_ACL_DACL);
189 break;
190 case XATTR_CIFS_ACL:
191 default:
192 aclflags = CIFS_ACL_DACL;
193 }
194
195 rc = pTcon->ses->server->ops->set_acl(pacl,
196 size, inode, full_path, aclflags);
197 } else {
198 rc = -EOPNOTSUPP;
199 }
200 if (rc == 0) /* force revalidate of the inode */
201 CIFS_I(inode)->time = 0;
202 kfree(pacl);
203 }
204 break;
205 }
206 }
207
208 out:
209 free_dentry_path(page);
210 free_xid(xid);
211 cifs_put_tlink(tlink);
212 return rc;
213 }
214
cifs_attrib_get(struct dentry * dentry,struct inode * inode,void * value,size_t size)215 static int cifs_attrib_get(struct dentry *dentry,
216 struct inode *inode, void *value,
217 size_t size)
218 {
219 ssize_t rc;
220 __u32 *pattribute;
221
222 rc = cifs_revalidate_dentry_attr(dentry);
223
224 if (rc)
225 return rc;
226
227 if ((value == NULL) || (size == 0))
228 return sizeof(__u32);
229 else if (size < sizeof(__u32))
230 return -ERANGE;
231
232 /* return dos attributes as pseudo xattr */
233 pattribute = (__u32 *)value;
234 *pattribute = CIFS_I(inode)->cifsAttrs;
235
236 return sizeof(__u32);
237 }
238
cifs_creation_time_get(struct dentry * dentry,struct inode * inode,void * value,size_t size)239 static int cifs_creation_time_get(struct dentry *dentry, struct inode *inode,
240 void *value, size_t size)
241 {
242 ssize_t rc;
243 __u64 *pcreatetime;
244
245 rc = cifs_revalidate_dentry_attr(dentry);
246 if (rc)
247 return rc;
248
249 if ((value == NULL) || (size == 0))
250 return sizeof(__u64);
251 else if (size < sizeof(__u64))
252 return -ERANGE;
253
254 /* return dos attributes as pseudo xattr */
255 pcreatetime = (__u64 *)value;
256 *pcreatetime = CIFS_I(inode)->createtime;
257 return sizeof(__u64);
258 }
259
260
cifs_xattr_get(const struct xattr_handler * handler,struct dentry * dentry,struct inode * inode,const char * name,void * value,size_t size)261 static int cifs_xattr_get(const struct xattr_handler *handler,
262 struct dentry *dentry, struct inode *inode,
263 const char *name, void *value, size_t size)
264 {
265 ssize_t rc = -EOPNOTSUPP;
266 unsigned int xid;
267 struct super_block *sb = dentry->d_sb;
268 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
269 struct tcon_link *tlink;
270 struct cifs_tcon *pTcon;
271 const char *full_path;
272 void *page;
273
274 tlink = cifs_sb_tlink(cifs_sb);
275 if (IS_ERR(tlink))
276 return PTR_ERR(tlink);
277 pTcon = tlink_tcon(tlink);
278
279 xid = get_xid();
280 page = alloc_dentry_path();
281
282 full_path = build_path_from_dentry(dentry, page);
283 if (IS_ERR(full_path)) {
284 rc = PTR_ERR(full_path);
285 goto out;
286 }
287
288 /* return alt name if available as pseudo attr */
289 switch (handler->flags) {
290 case XATTR_USER:
291 cifs_dbg(FYI, "%s:querying user xattr %s\n", __func__, name);
292 if ((strcmp(name, CIFS_XATTR_ATTRIB) == 0) ||
293 (strcmp(name, SMB3_XATTR_ATTRIB) == 0)) {
294 rc = cifs_attrib_get(dentry, inode, value, size);
295 break;
296 } else if ((strcmp(name, CIFS_XATTR_CREATETIME) == 0) ||
297 (strcmp(name, SMB3_XATTR_CREATETIME) == 0)) {
298 rc = cifs_creation_time_get(dentry, inode, value, size);
299 break;
300 }
301
302 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
303 goto out;
304
305 if (pTcon->ses->server->ops->query_all_EAs)
306 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
307 full_path, name, value, size, cifs_sb);
308 break;
309
310 case XATTR_CIFS_ACL:
311 case XATTR_CIFS_NTSD:
312 case XATTR_CIFS_NTSD_FULL: {
313 /*
314 * fetch owner, DACL, and SACL if asked for full descriptor,
315 * fetch owner and DACL otherwise
316 */
317 u32 acllen, extra_info;
318 struct cifs_ntsd *pacl;
319
320 if (pTcon->ses->server->ops->get_acl == NULL)
321 goto out; /* rc already EOPNOTSUPP */
322
323 if (handler->flags == XATTR_CIFS_NTSD_FULL) {
324 extra_info = SACL_SECINFO;
325 } else {
326 extra_info = 0;
327 }
328 pacl = pTcon->ses->server->ops->get_acl(cifs_sb,
329 inode, full_path, &acllen, extra_info);
330 if (IS_ERR(pacl)) {
331 rc = PTR_ERR(pacl);
332 cifs_dbg(VFS, "%s: error %zd getting sec desc\n",
333 __func__, rc);
334 } else {
335 if (value) {
336 if (acllen > size)
337 acllen = -ERANGE;
338 else
339 memcpy(value, pacl, acllen);
340 }
341 rc = acllen;
342 kfree(pacl);
343 }
344 break;
345 }
346 }
347
348 /* We could add an additional check for streams ie
349 if proc/fs/cifs/streamstoxattr is set then
350 search server for EAs or streams to
351 returns as xattrs */
352
353 if (rc == -EINVAL)
354 rc = -EOPNOTSUPP;
355
356 out:
357 free_dentry_path(page);
358 free_xid(xid);
359 cifs_put_tlink(tlink);
360 return rc;
361 }
362
cifs_listxattr(struct dentry * direntry,char * data,size_t buf_size)363 ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
364 {
365 ssize_t rc = -EOPNOTSUPP;
366 unsigned int xid;
367 struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
368 struct tcon_link *tlink;
369 struct cifs_tcon *pTcon;
370 const char *full_path;
371 void *page;
372
373 if (unlikely(cifs_forced_shutdown(cifs_sb)))
374 return -EIO;
375
376 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
377 return -EOPNOTSUPP;
378
379 tlink = cifs_sb_tlink(cifs_sb);
380 if (IS_ERR(tlink))
381 return PTR_ERR(tlink);
382 pTcon = tlink_tcon(tlink);
383
384 xid = get_xid();
385 page = alloc_dentry_path();
386
387 full_path = build_path_from_dentry(direntry, page);
388 if (IS_ERR(full_path)) {
389 rc = PTR_ERR(full_path);
390 goto list_ea_exit;
391 }
392 /* return dos attributes as pseudo xattr */
393 /* return alt name if available as pseudo attr */
394
395 /* if proc/fs/cifs/streamstoxattr is set then
396 search server for EAs or streams to
397 returns as xattrs */
398
399 if (pTcon->ses->server->ops->query_all_EAs)
400 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
401 full_path, NULL, data, buf_size, cifs_sb);
402 list_ea_exit:
403 free_dentry_path(page);
404 free_xid(xid);
405 cifs_put_tlink(tlink);
406 return rc;
407 }
408
409 static const struct xattr_handler cifs_user_xattr_handler = {
410 .prefix = XATTR_USER_PREFIX,
411 .flags = XATTR_USER,
412 .get = cifs_xattr_get,
413 .set = cifs_xattr_set,
414 };
415
416 /* os2.* attributes are treated like user.* attributes */
417 static const struct xattr_handler cifs_os2_xattr_handler = {
418 .prefix = XATTR_OS2_PREFIX,
419 .flags = XATTR_USER,
420 .get = cifs_xattr_get,
421 .set = cifs_xattr_set,
422 };
423
424 static const struct xattr_handler cifs_cifs_acl_xattr_handler = {
425 .name = CIFS_XATTR_CIFS_ACL,
426 .flags = XATTR_CIFS_ACL,
427 .get = cifs_xattr_get,
428 .set = cifs_xattr_set,
429 };
430
431 /*
432 * Although this is just an alias for the above, need to move away from
433 * confusing users and using the 20 year old term 'cifs' when it is no
434 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
435 * SMB3 and later are highly secure.
436 */
437 static const struct xattr_handler smb3_acl_xattr_handler = {
438 .name = SMB3_XATTR_CIFS_ACL,
439 .flags = XATTR_CIFS_ACL,
440 .get = cifs_xattr_get,
441 .set = cifs_xattr_set,
442 };
443
444 static const struct xattr_handler cifs_cifs_ntsd_xattr_handler = {
445 .name = CIFS_XATTR_CIFS_NTSD,
446 .flags = XATTR_CIFS_NTSD,
447 .get = cifs_xattr_get,
448 .set = cifs_xattr_set,
449 };
450
451 /*
452 * Although this is just an alias for the above, need to move away from
453 * confusing users and using the 20 year old term 'cifs' when it is no
454 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
455 * SMB3 and later are highly secure.
456 */
457 static const struct xattr_handler smb3_ntsd_xattr_handler = {
458 .name = SMB3_XATTR_CIFS_NTSD,
459 .flags = XATTR_CIFS_NTSD,
460 .get = cifs_xattr_get,
461 .set = cifs_xattr_set,
462 };
463
464 static const struct xattr_handler cifs_cifs_ntsd_full_xattr_handler = {
465 .name = CIFS_XATTR_CIFS_NTSD_FULL,
466 .flags = XATTR_CIFS_NTSD_FULL,
467 .get = cifs_xattr_get,
468 .set = cifs_xattr_set,
469 };
470
471 /*
472 * Although this is just an alias for the above, need to move away from
473 * confusing users and using the 20 year old term 'cifs' when it is no
474 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
475 * SMB3 and later are highly secure.
476 */
477 static const struct xattr_handler smb3_ntsd_full_xattr_handler = {
478 .name = SMB3_XATTR_CIFS_NTSD_FULL,
479 .flags = XATTR_CIFS_NTSD_FULL,
480 .get = cifs_xattr_get,
481 .set = cifs_xattr_set,
482 };
483
484 const struct xattr_handler *cifs_xattr_handlers[] = {
485 &cifs_user_xattr_handler,
486 &cifs_os2_xattr_handler,
487 &cifs_cifs_acl_xattr_handler,
488 &smb3_acl_xattr_handler, /* alias for above since avoiding "cifs" */
489 &cifs_cifs_ntsd_xattr_handler,
490 &smb3_ntsd_xattr_handler, /* alias for above since avoiding "cifs" */
491 &cifs_cifs_ntsd_full_xattr_handler,
492 &smb3_ntsd_full_xattr_handler, /* alias for above since avoiding "cifs" */
493 NULL
494 };
495