1 /*
2 * fs/cifs/xattr.c
3 *
4 * Copyright (c) International Business Machines Corp., 2003, 2007
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This library 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
15 * the GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22 #include <linux/fs.h>
23 #include <linux/posix_acl_xattr.h>
24 #include <linux/slab.h>
25 #include <linux/xattr.h>
26 #include "cifsfs.h"
27 #include "cifspdu.h"
28 #include "cifsglob.h"
29 #include "cifsproto.h"
30 #include "cifs_debug.h"
31 #include "cifs_fs_sb.h"
32 #include "cifs_unicode.h"
33
34 #define MAX_EA_VALUE_SIZE CIFSMaxBufSize
35 #define CIFS_XATTR_CIFS_ACL "system.cifs_acl" /* DACL only */
36 #define CIFS_XATTR_CIFS_NTSD "system.cifs_ntsd" /* owner plus DACL */
37 #define CIFS_XATTR_ATTRIB "cifs.dosattrib" /* full name: user.cifs.dosattrib */
38 #define CIFS_XATTR_CREATETIME "cifs.creationtime" /* user.cifs.creationtime */
39 /*
40 * Although these three are just aliases for the above, need to move away from
41 * confusing users and using the 20+ year old term 'cifs' when it is no longer
42 * secure, replaced by SMB2 (then even more highly secure SMB3) many years ago
43 */
44 #define SMB3_XATTR_CIFS_ACL "system.smb3_acl" /* DACL only */
45 #define SMB3_XATTR_CIFS_NTSD "system.smb3_ntsd" /* owner plus DACL */
46 #define SMB3_XATTR_ATTRIB "smb3.dosattrib" /* full name: user.smb3.dosattrib */
47 #define SMB3_XATTR_CREATETIME "smb3.creationtime" /* user.smb3.creationtime */
48 /* BB need to add server (Samba e.g) support for security and trusted prefix */
49
50 enum { XATTR_USER, XATTR_CIFS_ACL, XATTR_ACL_ACCESS, XATTR_ACL_DEFAULT,
51 XATTR_CIFS_NTSD };
52
cifs_attrib_set(unsigned int xid,struct cifs_tcon * pTcon,struct inode * inode,char * full_path,const void * value,size_t size)53 static int cifs_attrib_set(unsigned int xid, struct cifs_tcon *pTcon,
54 struct inode *inode, char *full_path,
55 const void *value, size_t size)
56 {
57 ssize_t rc = -EOPNOTSUPP;
58 __u32 *pattrib = (__u32 *)value;
59 __u32 attrib;
60 FILE_BASIC_INFO info_buf;
61
62 if ((value == NULL) || (size != sizeof(__u32)))
63 return -ERANGE;
64
65 memset(&info_buf, 0, sizeof(info_buf));
66 attrib = *pattrib;
67 info_buf.Attributes = cpu_to_le32(attrib);
68 if (pTcon->ses->server->ops->set_file_info)
69 rc = pTcon->ses->server->ops->set_file_info(inode, full_path,
70 &info_buf, xid);
71 if (rc == 0)
72 CIFS_I(inode)->cifsAttrs = attrib;
73
74 return rc;
75 }
76
cifs_creation_time_set(unsigned int xid,struct cifs_tcon * pTcon,struct inode * inode,char * full_path,const void * value,size_t size)77 static int cifs_creation_time_set(unsigned int xid, struct cifs_tcon *pTcon,
78 struct inode *inode, char *full_path,
79 const void *value, size_t size)
80 {
81 ssize_t rc = -EOPNOTSUPP;
82 __u64 *pcreation_time = (__u64 *)value;
83 __u64 creation_time;
84 FILE_BASIC_INFO info_buf;
85
86 if ((value == NULL) || (size != sizeof(__u64)))
87 return -ERANGE;
88
89 memset(&info_buf, 0, sizeof(info_buf));
90 creation_time = *pcreation_time;
91 info_buf.CreationTime = cpu_to_le64(creation_time);
92 if (pTcon->ses->server->ops->set_file_info)
93 rc = pTcon->ses->server->ops->set_file_info(inode, full_path,
94 &info_buf, xid);
95 if (rc == 0)
96 CIFS_I(inode)->createtime = creation_time;
97
98 return rc;
99 }
100
cifs_xattr_set(const struct xattr_handler * handler,struct dentry * dentry,struct inode * inode,const char * name,const void * value,size_t size,int flags)101 static int cifs_xattr_set(const struct xattr_handler *handler,
102 struct dentry *dentry, struct inode *inode,
103 const char *name, const void *value,
104 size_t size, int flags)
105 {
106 int rc = -EOPNOTSUPP;
107 unsigned int xid;
108 struct super_block *sb = dentry->d_sb;
109 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
110 struct tcon_link *tlink;
111 struct cifs_tcon *pTcon;
112 char *full_path;
113
114 tlink = cifs_sb_tlink(cifs_sb);
115 if (IS_ERR(tlink))
116 return PTR_ERR(tlink);
117 pTcon = tlink_tcon(tlink);
118
119 xid = get_xid();
120
121 full_path = build_path_from_dentry(dentry);
122 if (full_path == NULL) {
123 rc = -ENOMEM;
124 goto out;
125 }
126 /* return dos attributes as pseudo xattr */
127 /* return alt name if available as pseudo attr */
128
129 /* if proc/fs/cifs/streamstoxattr is set then
130 search server for EAs or streams to
131 returns as xattrs */
132 if (size > MAX_EA_VALUE_SIZE) {
133 cifs_dbg(FYI, "size of EA value too large\n");
134 rc = -EOPNOTSUPP;
135 goto out;
136 }
137
138 switch (handler->flags) {
139 case XATTR_USER:
140 cifs_dbg(FYI, "%s:setting user xattr %s\n", __func__, name);
141 if ((strcmp(name, CIFS_XATTR_ATTRIB) == 0) ||
142 (strcmp(name, SMB3_XATTR_ATTRIB) == 0)) {
143 rc = cifs_attrib_set(xid, pTcon, inode, full_path,
144 value, size);
145 if (rc == 0) /* force revalidate of the inode */
146 CIFS_I(inode)->time = 0;
147 break;
148 } else if ((strcmp(name, CIFS_XATTR_CREATETIME) == 0) ||
149 (strcmp(name, SMB3_XATTR_CREATETIME) == 0)) {
150 rc = cifs_creation_time_set(xid, pTcon, inode,
151 full_path, value, size);
152 if (rc == 0) /* force revalidate of the inode */
153 CIFS_I(inode)->time = 0;
154 break;
155 }
156
157 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
158 goto out;
159
160 if (pTcon->ses->server->ops->set_EA)
161 rc = pTcon->ses->server->ops->set_EA(xid, pTcon,
162 full_path, name, value, (__u16)size,
163 cifs_sb->local_nls, cifs_sb);
164 break;
165
166 case XATTR_CIFS_ACL:
167 case XATTR_CIFS_NTSD: {
168 struct cifs_ntsd *pacl;
169
170 if (!value)
171 goto out;
172 pacl = kmalloc(size, GFP_KERNEL);
173 if (!pacl) {
174 rc = -ENOMEM;
175 } else {
176 memcpy(pacl, value, size);
177 if (value &&
178 pTcon->ses->server->ops->set_acl) {
179 rc = 0;
180 if (handler->flags == XATTR_CIFS_NTSD) {
181 /* set owner and DACL */
182 rc = pTcon->ses->server->ops->set_acl(
183 pacl, size, inode,
184 full_path,
185 CIFS_ACL_OWNER);
186 }
187 if (rc == 0) {
188 /* set DACL */
189 rc = pTcon->ses->server->ops->set_acl(
190 pacl, size, inode,
191 full_path,
192 CIFS_ACL_DACL);
193 }
194 } else {
195 rc = -EOPNOTSUPP;
196 }
197 if (rc == 0) /* force revalidate of the inode */
198 CIFS_I(inode)->time = 0;
199 kfree(pacl);
200 }
201 break;
202 }
203
204 case XATTR_ACL_ACCESS:
205 #ifdef CONFIG_CIFS_POSIX
206 if (!value)
207 goto out;
208 if (sb->s_flags & SB_POSIXACL)
209 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
210 value, (const int)size,
211 ACL_TYPE_ACCESS, cifs_sb->local_nls,
212 cifs_remap(cifs_sb));
213 #endif /* CONFIG_CIFS_POSIX */
214 break;
215
216 case XATTR_ACL_DEFAULT:
217 #ifdef CONFIG_CIFS_POSIX
218 if (!value)
219 goto out;
220 if (sb->s_flags & SB_POSIXACL)
221 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
222 value, (const int)size,
223 ACL_TYPE_DEFAULT, cifs_sb->local_nls,
224 cifs_remap(cifs_sb));
225 #endif /* CONFIG_CIFS_POSIX */
226 break;
227 }
228
229 out:
230 kfree(full_path);
231 free_xid(xid);
232 cifs_put_tlink(tlink);
233 return rc;
234 }
235
cifs_attrib_get(struct dentry * dentry,struct inode * inode,void * value,size_t size)236 static int cifs_attrib_get(struct dentry *dentry,
237 struct inode *inode, void *value,
238 size_t size)
239 {
240 ssize_t rc;
241 __u32 *pattribute;
242
243 rc = cifs_revalidate_dentry_attr(dentry);
244
245 if (rc)
246 return rc;
247
248 if ((value == NULL) || (size == 0))
249 return sizeof(__u32);
250 else if (size < sizeof(__u32))
251 return -ERANGE;
252
253 /* return dos attributes as pseudo xattr */
254 pattribute = (__u32 *)value;
255 *pattribute = CIFS_I(inode)->cifsAttrs;
256
257 return sizeof(__u32);
258 }
259
cifs_creation_time_get(struct dentry * dentry,struct inode * inode,void * value,size_t size)260 static int cifs_creation_time_get(struct dentry *dentry, struct inode *inode,
261 void *value, size_t size)
262 {
263 ssize_t rc;
264 __u64 *pcreatetime;
265
266 rc = cifs_revalidate_dentry_attr(dentry);
267 if (rc)
268 return rc;
269
270 if ((value == NULL) || (size == 0))
271 return sizeof(__u64);
272 else if (size < sizeof(__u64))
273 return -ERANGE;
274
275 /* return dos attributes as pseudo xattr */
276 pcreatetime = (__u64 *)value;
277 *pcreatetime = CIFS_I(inode)->createtime;
278 return sizeof(__u64);
279 }
280
281
cifs_xattr_get(const struct xattr_handler * handler,struct dentry * dentry,struct inode * inode,const char * name,void * value,size_t size)282 static int cifs_xattr_get(const struct xattr_handler *handler,
283 struct dentry *dentry, struct inode *inode,
284 const char *name, void *value, size_t size)
285 {
286 ssize_t rc = -EOPNOTSUPP;
287 unsigned int xid;
288 struct super_block *sb = dentry->d_sb;
289 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
290 struct tcon_link *tlink;
291 struct cifs_tcon *pTcon;
292 char *full_path;
293
294 tlink = cifs_sb_tlink(cifs_sb);
295 if (IS_ERR(tlink))
296 return PTR_ERR(tlink);
297 pTcon = tlink_tcon(tlink);
298
299 xid = get_xid();
300
301 full_path = build_path_from_dentry(dentry);
302 if (full_path == NULL) {
303 rc = -ENOMEM;
304 goto out;
305 }
306
307 /* return alt name if available as pseudo attr */
308 switch (handler->flags) {
309 case XATTR_USER:
310 cifs_dbg(FYI, "%s:querying user xattr %s\n", __func__, name);
311 if ((strcmp(name, CIFS_XATTR_ATTRIB) == 0) ||
312 (strcmp(name, SMB3_XATTR_ATTRIB) == 0)) {
313 rc = cifs_attrib_get(dentry, inode, value, size);
314 break;
315 } else if ((strcmp(name, CIFS_XATTR_CREATETIME) == 0) ||
316 (strcmp(name, SMB3_XATTR_CREATETIME) == 0)) {
317 rc = cifs_creation_time_get(dentry, inode, value, size);
318 break;
319 }
320
321 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
322 goto out;
323
324 if (pTcon->ses->server->ops->query_all_EAs)
325 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
326 full_path, name, value, size, cifs_sb);
327 break;
328
329 case XATTR_CIFS_ACL:
330 case XATTR_CIFS_NTSD: {
331 /* the whole ntsd is fetched regardless */
332 u32 acllen;
333 struct cifs_ntsd *pacl;
334
335 if (pTcon->ses->server->ops->get_acl == NULL)
336 goto out; /* rc already EOPNOTSUPP */
337
338 pacl = pTcon->ses->server->ops->get_acl(cifs_sb,
339 inode, full_path, &acllen);
340 if (IS_ERR(pacl)) {
341 rc = PTR_ERR(pacl);
342 cifs_dbg(VFS, "%s: error %zd getting sec desc\n",
343 __func__, rc);
344 } else {
345 if (value) {
346 if (acllen > size)
347 acllen = -ERANGE;
348 else
349 memcpy(value, pacl, acllen);
350 }
351 rc = acllen;
352 kfree(pacl);
353 }
354 break;
355 }
356
357 case XATTR_ACL_ACCESS:
358 #ifdef CONFIG_CIFS_POSIX
359 if (sb->s_flags & SB_POSIXACL)
360 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
361 value, size, ACL_TYPE_ACCESS,
362 cifs_sb->local_nls,
363 cifs_remap(cifs_sb));
364 #endif /* CONFIG_CIFS_POSIX */
365 break;
366
367 case XATTR_ACL_DEFAULT:
368 #ifdef CONFIG_CIFS_POSIX
369 if (sb->s_flags & SB_POSIXACL)
370 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
371 value, size, ACL_TYPE_DEFAULT,
372 cifs_sb->local_nls,
373 cifs_remap(cifs_sb));
374 #endif /* CONFIG_CIFS_POSIX */
375 break;
376 }
377
378 /* We could add an additional check for streams ie
379 if proc/fs/cifs/streamstoxattr is set then
380 search server for EAs or streams to
381 returns as xattrs */
382
383 if (rc == -EINVAL)
384 rc = -EOPNOTSUPP;
385
386 out:
387 kfree(full_path);
388 free_xid(xid);
389 cifs_put_tlink(tlink);
390 return rc;
391 }
392
cifs_listxattr(struct dentry * direntry,char * data,size_t buf_size)393 ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
394 {
395 ssize_t rc = -EOPNOTSUPP;
396 unsigned int xid;
397 struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
398 struct tcon_link *tlink;
399 struct cifs_tcon *pTcon;
400 char *full_path;
401
402 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
403 return -EOPNOTSUPP;
404
405 tlink = cifs_sb_tlink(cifs_sb);
406 if (IS_ERR(tlink))
407 return PTR_ERR(tlink);
408 pTcon = tlink_tcon(tlink);
409
410 xid = get_xid();
411
412 full_path = build_path_from_dentry(direntry);
413 if (full_path == NULL) {
414 rc = -ENOMEM;
415 goto list_ea_exit;
416 }
417 /* return dos attributes as pseudo xattr */
418 /* return alt name if available as pseudo attr */
419
420 /* if proc/fs/cifs/streamstoxattr is set then
421 search server for EAs or streams to
422 returns as xattrs */
423
424 if (pTcon->ses->server->ops->query_all_EAs)
425 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
426 full_path, NULL, data, buf_size, cifs_sb);
427 list_ea_exit:
428 kfree(full_path);
429 free_xid(xid);
430 cifs_put_tlink(tlink);
431 return rc;
432 }
433
434 static const struct xattr_handler cifs_user_xattr_handler = {
435 .prefix = XATTR_USER_PREFIX,
436 .flags = XATTR_USER,
437 .get = cifs_xattr_get,
438 .set = cifs_xattr_set,
439 };
440
441 /* os2.* attributes are treated like user.* attributes */
442 static const struct xattr_handler cifs_os2_xattr_handler = {
443 .prefix = XATTR_OS2_PREFIX,
444 .flags = XATTR_USER,
445 .get = cifs_xattr_get,
446 .set = cifs_xattr_set,
447 };
448
449 static const struct xattr_handler cifs_cifs_acl_xattr_handler = {
450 .name = CIFS_XATTR_CIFS_ACL,
451 .flags = XATTR_CIFS_ACL,
452 .get = cifs_xattr_get,
453 .set = cifs_xattr_set,
454 };
455
456 /*
457 * Although this is just an alias for the above, need to move away from
458 * confusing users and using the 20 year old term 'cifs' when it is no
459 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
460 * SMB3 and later are highly secure.
461 */
462 static const struct xattr_handler smb3_acl_xattr_handler = {
463 .name = SMB3_XATTR_CIFS_ACL,
464 .flags = XATTR_CIFS_ACL,
465 .get = cifs_xattr_get,
466 .set = cifs_xattr_set,
467 };
468
469 static const struct xattr_handler cifs_cifs_ntsd_xattr_handler = {
470 .name = CIFS_XATTR_CIFS_NTSD,
471 .flags = XATTR_CIFS_NTSD,
472 .get = cifs_xattr_get,
473 .set = cifs_xattr_set,
474 };
475
476 /*
477 * Although this is just an alias for the above, need to move away from
478 * confusing users and using the 20 year old term 'cifs' when it is no
479 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
480 * SMB3 and later are highly secure.
481 */
482 static const struct xattr_handler smb3_ntsd_xattr_handler = {
483 .name = SMB3_XATTR_CIFS_NTSD,
484 .flags = XATTR_CIFS_NTSD,
485 .get = cifs_xattr_get,
486 .set = cifs_xattr_set,
487 };
488
489 static const struct xattr_handler cifs_posix_acl_access_xattr_handler = {
490 .name = XATTR_NAME_POSIX_ACL_ACCESS,
491 .flags = XATTR_ACL_ACCESS,
492 .get = cifs_xattr_get,
493 .set = cifs_xattr_set,
494 };
495
496 static const struct xattr_handler cifs_posix_acl_default_xattr_handler = {
497 .name = XATTR_NAME_POSIX_ACL_DEFAULT,
498 .flags = XATTR_ACL_DEFAULT,
499 .get = cifs_xattr_get,
500 .set = cifs_xattr_set,
501 };
502
503 const struct xattr_handler *cifs_xattr_handlers[] = {
504 &cifs_user_xattr_handler,
505 &cifs_os2_xattr_handler,
506 &cifs_cifs_acl_xattr_handler,
507 &smb3_acl_xattr_handler, /* alias for above since avoiding "cifs" */
508 &cifs_cifs_ntsd_xattr_handler,
509 &smb3_ntsd_xattr_handler, /* alias for above since avoiding "cifs" */
510 &cifs_posix_acl_access_xattr_handler,
511 &cifs_posix_acl_default_xattr_handler,
512 NULL
513 };
514
