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 user_namespace * mnt_userns,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 user_namespace *mnt_userns,
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 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
208 case XATTR_ACL_ACCESS:
209 #ifdef CONFIG_CIFS_POSIX
210 if (!value)
211 goto out;
212 if (sb->s_flags & SB_POSIXACL)
213 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
214 value, (const int)size,
215 ACL_TYPE_ACCESS, cifs_sb->local_nls,
216 cifs_remap(cifs_sb));
217 #endif /* CONFIG_CIFS_POSIX */
218 break;
219
220 case XATTR_ACL_DEFAULT:
221 #ifdef CONFIG_CIFS_POSIX
222 if (!value)
223 goto out;
224 if (sb->s_flags & SB_POSIXACL)
225 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
226 value, (const int)size,
227 ACL_TYPE_DEFAULT, cifs_sb->local_nls,
228 cifs_remap(cifs_sb));
229 #endif /* CONFIG_CIFS_POSIX */
230 break;
231 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
232 }
233
234 out:
235 free_dentry_path(page);
236 free_xid(xid);
237 cifs_put_tlink(tlink);
238 return rc;
239 }
240
cifs_attrib_get(struct dentry * dentry,struct inode * inode,void * value,size_t size)241 static int cifs_attrib_get(struct dentry *dentry,
242 struct inode *inode, void *value,
243 size_t size)
244 {
245 ssize_t rc;
246 __u32 *pattribute;
247
248 rc = cifs_revalidate_dentry_attr(dentry);
249
250 if (rc)
251 return rc;
252
253 if ((value == NULL) || (size == 0))
254 return sizeof(__u32);
255 else if (size < sizeof(__u32))
256 return -ERANGE;
257
258 /* return dos attributes as pseudo xattr */
259 pattribute = (__u32 *)value;
260 *pattribute = CIFS_I(inode)->cifsAttrs;
261
262 return sizeof(__u32);
263 }
264
cifs_creation_time_get(struct dentry * dentry,struct inode * inode,void * value,size_t size)265 static int cifs_creation_time_get(struct dentry *dentry, struct inode *inode,
266 void *value, size_t size)
267 {
268 ssize_t rc;
269 __u64 *pcreatetime;
270
271 rc = cifs_revalidate_dentry_attr(dentry);
272 if (rc)
273 return rc;
274
275 if ((value == NULL) || (size == 0))
276 return sizeof(__u64);
277 else if (size < sizeof(__u64))
278 return -ERANGE;
279
280 /* return dos attributes as pseudo xattr */
281 pcreatetime = (__u64 *)value;
282 *pcreatetime = CIFS_I(inode)->createtime;
283 return sizeof(__u64);
284 }
285
286
cifs_xattr_get(const struct xattr_handler * handler,struct dentry * dentry,struct inode * inode,const char * name,void * value,size_t size)287 static int cifs_xattr_get(const struct xattr_handler *handler,
288 struct dentry *dentry, struct inode *inode,
289 const char *name, void *value, size_t size)
290 {
291 ssize_t rc = -EOPNOTSUPP;
292 unsigned int xid;
293 struct super_block *sb = dentry->d_sb;
294 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
295 struct tcon_link *tlink;
296 struct cifs_tcon *pTcon;
297 const char *full_path;
298 void *page;
299
300 tlink = cifs_sb_tlink(cifs_sb);
301 if (IS_ERR(tlink))
302 return PTR_ERR(tlink);
303 pTcon = tlink_tcon(tlink);
304
305 xid = get_xid();
306 page = alloc_dentry_path();
307
308 full_path = build_path_from_dentry(dentry, page);
309 if (IS_ERR(full_path)) {
310 rc = PTR_ERR(full_path);
311 goto out;
312 }
313
314 /* return alt name if available as pseudo attr */
315 switch (handler->flags) {
316 case XATTR_USER:
317 cifs_dbg(FYI, "%s:querying user xattr %s\n", __func__, name);
318 if ((strcmp(name, CIFS_XATTR_ATTRIB) == 0) ||
319 (strcmp(name, SMB3_XATTR_ATTRIB) == 0)) {
320 rc = cifs_attrib_get(dentry, inode, value, size);
321 break;
322 } else if ((strcmp(name, CIFS_XATTR_CREATETIME) == 0) ||
323 (strcmp(name, SMB3_XATTR_CREATETIME) == 0)) {
324 rc = cifs_creation_time_get(dentry, inode, value, size);
325 break;
326 }
327
328 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
329 goto out;
330
331 if (pTcon->ses->server->ops->query_all_EAs)
332 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
333 full_path, name, value, size, cifs_sb);
334 break;
335
336 case XATTR_CIFS_ACL:
337 case XATTR_CIFS_NTSD:
338 case XATTR_CIFS_NTSD_FULL: {
339 /*
340 * fetch owner, DACL, and SACL if asked for full descriptor,
341 * fetch owner and DACL otherwise
342 */
343 u32 acllen, extra_info;
344 struct cifs_ntsd *pacl;
345
346 if (pTcon->ses->server->ops->get_acl == NULL)
347 goto out; /* rc already EOPNOTSUPP */
348
349 if (handler->flags == XATTR_CIFS_NTSD_FULL) {
350 extra_info = SACL_SECINFO;
351 } else {
352 extra_info = 0;
353 }
354 pacl = pTcon->ses->server->ops->get_acl(cifs_sb,
355 inode, full_path, &acllen, extra_info);
356 if (IS_ERR(pacl)) {
357 rc = PTR_ERR(pacl);
358 cifs_dbg(VFS, "%s: error %zd getting sec desc\n",
359 __func__, rc);
360 } else {
361 if (value) {
362 if (acllen > size)
363 acllen = -ERANGE;
364 else
365 memcpy(value, pacl, acllen);
366 }
367 rc = acllen;
368 kfree(pacl);
369 }
370 break;
371 }
372 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
373 case XATTR_ACL_ACCESS:
374 #ifdef CONFIG_CIFS_POSIX
375 if (sb->s_flags & SB_POSIXACL)
376 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
377 value, size, ACL_TYPE_ACCESS,
378 cifs_sb->local_nls,
379 cifs_remap(cifs_sb));
380 #endif /* CONFIG_CIFS_POSIX */
381 break;
382
383 case XATTR_ACL_DEFAULT:
384 #ifdef CONFIG_CIFS_POSIX
385 if (sb->s_flags & SB_POSIXACL)
386 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
387 value, size, ACL_TYPE_DEFAULT,
388 cifs_sb->local_nls,
389 cifs_remap(cifs_sb));
390 #endif /* CONFIG_CIFS_POSIX */
391 break;
392 #endif /* ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
393 }
394
395 /* We could add an additional check for streams ie
396 if proc/fs/cifs/streamstoxattr is set then
397 search server for EAs or streams to
398 returns as xattrs */
399
400 if (rc == -EINVAL)
401 rc = -EOPNOTSUPP;
402
403 out:
404 free_dentry_path(page);
405 free_xid(xid);
406 cifs_put_tlink(tlink);
407 return rc;
408 }
409
cifs_listxattr(struct dentry * direntry,char * data,size_t buf_size)410 ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
411 {
412 ssize_t rc = -EOPNOTSUPP;
413 unsigned int xid;
414 struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
415 struct tcon_link *tlink;
416 struct cifs_tcon *pTcon;
417 const char *full_path;
418 void *page;
419
420 if (unlikely(cifs_forced_shutdown(cifs_sb)))
421 return -EIO;
422
423 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
424 return -EOPNOTSUPP;
425
426 tlink = cifs_sb_tlink(cifs_sb);
427 if (IS_ERR(tlink))
428 return PTR_ERR(tlink);
429 pTcon = tlink_tcon(tlink);
430
431 xid = get_xid();
432 page = alloc_dentry_path();
433
434 full_path = build_path_from_dentry(direntry, page);
435 if (IS_ERR(full_path)) {
436 rc = PTR_ERR(full_path);
437 goto list_ea_exit;
438 }
439 /* return dos attributes as pseudo xattr */
440 /* return alt name if available as pseudo attr */
441
442 /* if proc/fs/cifs/streamstoxattr is set then
443 search server for EAs or streams to
444 returns as xattrs */
445
446 if (pTcon->ses->server->ops->query_all_EAs)
447 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
448 full_path, NULL, data, buf_size, cifs_sb);
449 list_ea_exit:
450 free_dentry_path(page);
451 free_xid(xid);
452 cifs_put_tlink(tlink);
453 return rc;
454 }
455
456 static const struct xattr_handler cifs_user_xattr_handler = {
457 .prefix = XATTR_USER_PREFIX,
458 .flags = XATTR_USER,
459 .get = cifs_xattr_get,
460 .set = cifs_xattr_set,
461 };
462
463 /* os2.* attributes are treated like user.* attributes */
464 static const struct xattr_handler cifs_os2_xattr_handler = {
465 .prefix = XATTR_OS2_PREFIX,
466 .flags = XATTR_USER,
467 .get = cifs_xattr_get,
468 .set = cifs_xattr_set,
469 };
470
471 static const struct xattr_handler cifs_cifs_acl_xattr_handler = {
472 .name = CIFS_XATTR_CIFS_ACL,
473 .flags = XATTR_CIFS_ACL,
474 .get = cifs_xattr_get,
475 .set = cifs_xattr_set,
476 };
477
478 /*
479 * Although this is just an alias for the above, need to move away from
480 * confusing users and using the 20 year old term 'cifs' when it is no
481 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
482 * SMB3 and later are highly secure.
483 */
484 static const struct xattr_handler smb3_acl_xattr_handler = {
485 .name = SMB3_XATTR_CIFS_ACL,
486 .flags = XATTR_CIFS_ACL,
487 .get = cifs_xattr_get,
488 .set = cifs_xattr_set,
489 };
490
491 static const struct xattr_handler cifs_cifs_ntsd_xattr_handler = {
492 .name = CIFS_XATTR_CIFS_NTSD,
493 .flags = XATTR_CIFS_NTSD,
494 .get = cifs_xattr_get,
495 .set = cifs_xattr_set,
496 };
497
498 /*
499 * Although this is just an alias for the above, need to move away from
500 * confusing users and using the 20 year old term 'cifs' when it is no
501 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
502 * SMB3 and later are highly secure.
503 */
504 static const struct xattr_handler smb3_ntsd_xattr_handler = {
505 .name = SMB3_XATTR_CIFS_NTSD,
506 .flags = XATTR_CIFS_NTSD,
507 .get = cifs_xattr_get,
508 .set = cifs_xattr_set,
509 };
510
511 static const struct xattr_handler cifs_cifs_ntsd_full_xattr_handler = {
512 .name = CIFS_XATTR_CIFS_NTSD_FULL,
513 .flags = XATTR_CIFS_NTSD_FULL,
514 .get = cifs_xattr_get,
515 .set = cifs_xattr_set,
516 };
517
518 /*
519 * Although this is just an alias for the above, need to move away from
520 * confusing users and using the 20 year old term 'cifs' when it is no
521 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
522 * SMB3 and later are highly secure.
523 */
524 static const struct xattr_handler smb3_ntsd_full_xattr_handler = {
525 .name = SMB3_XATTR_CIFS_NTSD_FULL,
526 .flags = XATTR_CIFS_NTSD_FULL,
527 .get = cifs_xattr_get,
528 .set = cifs_xattr_set,
529 };
530
531
532 static const struct xattr_handler cifs_posix_acl_access_xattr_handler = {
533 .name = XATTR_NAME_POSIX_ACL_ACCESS,
534 .flags = XATTR_ACL_ACCESS,
535 .get = cifs_xattr_get,
536 .set = cifs_xattr_set,
537 };
538
539 static const struct xattr_handler cifs_posix_acl_default_xattr_handler = {
540 .name = XATTR_NAME_POSIX_ACL_DEFAULT,
541 .flags = XATTR_ACL_DEFAULT,
542 .get = cifs_xattr_get,
543 .set = cifs_xattr_set,
544 };
545
546 const struct xattr_handler *cifs_xattr_handlers[] = {
547 &cifs_user_xattr_handler,
548 &cifs_os2_xattr_handler,
549 &cifs_cifs_acl_xattr_handler,
550 &smb3_acl_xattr_handler, /* alias for above since avoiding "cifs" */
551 &cifs_cifs_ntsd_xattr_handler,
552 &smb3_ntsd_xattr_handler, /* alias for above since avoiding "cifs" */
553 &cifs_cifs_ntsd_full_xattr_handler,
554 &smb3_ntsd_full_xattr_handler, /* alias for above since avoiding "cifs" */
555 &cifs_posix_acl_access_xattr_handler,
556 &cifs_posix_acl_default_xattr_handler,
557 NULL
558 };
559