overlayfs: Implement splice-read
[linux-block.git] / fs / cifs / xattr.c
CommitLineData
929be906 1// SPDX-License-Identifier: LGPL-2.1
1da177e4 2/*
1da177e4 3 *
79a58d1f 4 * Copyright (c) International Business Machines Corp., 2003, 2007
1da177e4
LT
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
1da177e4
LT
7 */
8
9#include <linux/fs.h>
10#include <linux/posix_acl_xattr.h>
5a0e3ad6 11#include <linux/slab.h>
f995e740 12#include <linux/xattr.h>
1da177e4
LT
13#include "cifsfs.h"
14#include "cifspdu.h"
15#include "cifsglob.h"
16#include "cifsproto.h"
17#include "cifs_debug.h"
2baa2682
SF
18#include "cifs_fs_sb.h"
19#include "cifs_unicode.h"
087f757b 20#include "cifs_ioctl.h"
1da177e4 21
63d37fb4 22#define MAX_EA_VALUE_SIZE CIFSMaxBufSize
438471b6
BP
23#define CIFS_XATTR_CIFS_ACL "system.cifs_acl" /* DACL only */
24#define CIFS_XATTR_CIFS_NTSD "system.cifs_ntsd" /* owner plus DACL */
3970acf7 25#define CIFS_XATTR_CIFS_NTSD_FULL "system.cifs_ntsd_full" /* owner/DACL/SACL */
a958fff2 26#define CIFS_XATTR_ATTRIB "cifs.dosattrib" /* full name: user.cifs.dosattrib */
66098044 27#define CIFS_XATTR_CREATETIME "cifs.creationtime" /* user.cifs.creationtime */
c4f7173a
SF
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 */
438471b6
BP
33#define SMB3_XATTR_CIFS_ACL "system.smb3_acl" /* DACL only */
34#define SMB3_XATTR_CIFS_NTSD "system.smb3_ntsd" /* owner plus DACL */
3970acf7 35#define SMB3_XATTR_CIFS_NTSD_FULL "system.smb3_ntsd_full" /* owner/DACL/SACL */
c4f7173a
SF
36#define SMB3_XATTR_ATTRIB "smb3.dosattrib" /* full name: user.smb3.dosattrib */
37#define SMB3_XATTR_CREATETIME "smb3.creationtime" /* user.smb3.creationtime */
f995e740 38/* BB need to add server (Samba e.g) support for security and trusted prefix */
1da177e4 39
438471b6 40enum { XATTR_USER, XATTR_CIFS_ACL, XATTR_ACL_ACCESS, XATTR_ACL_DEFAULT,
3970acf7 41 XATTR_CIFS_NTSD, XATTR_CIFS_NTSD_FULL };
438471b6
BP
42
43static int cifs_attrib_set(unsigned int xid, struct cifs_tcon *pTcon,
f6f1f179 44 struct inode *inode, const char *full_path,
438471b6
BP
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
67static int cifs_creation_time_set(unsigned int xid, struct cifs_tcon *pTcon,
f6f1f179 68 struct inode *inode, const char *full_path,
438471b6
BP
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}
7ffec372 90
a9ae008f 91static int cifs_xattr_set(const struct xattr_handler *handler,
39f60c1c 92 struct mnt_idmap *idmap,
59301226
AV
93 struct dentry *dentry, struct inode *inode,
94 const char *name, const void *value,
95 size_t size, int flags)
1da177e4
LT
96{
97 int rc = -EOPNOTSUPP;
6d5786a3 98 unsigned int xid;
a9ae008f 99 struct super_block *sb = dentry->d_sb;
5fdccfef 100 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
7ffec372 101 struct tcon_link *tlink;
96daf2b0 102 struct cifs_tcon *pTcon;
8e33cf20 103 const char *full_path;
f6a9bc33 104 void *page;
1da177e4 105
7ffec372
JL
106 tlink = cifs_sb_tlink(cifs_sb);
107 if (IS_ERR(tlink))
108 return PTR_ERR(tlink);
109 pTcon = tlink_tcon(tlink);
110
6d5786a3 111 xid = get_xid();
f6a9bc33 112 page = alloc_dentry_path();
1da177e4 113
f6a9bc33
AV
114 full_path = build_path_from_dentry(dentry, page);
115 if (IS_ERR(full_path)) {
116 rc = PTR_ERR(full_path);
a9ae008f 117 goto out;
1da177e4
LT
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
79a58d1f 123 search server for EAs or streams to
1da177e4 124 returns as xattrs */
a9ae008f 125 if (size > MAX_EA_VALUE_SIZE) {
f96637be 126 cifs_dbg(FYI, "size of EA value too large\n");
7ffec372 127 rc = -EOPNOTSUPP;
a9ae008f 128 goto out;
1da177e4
LT
129 }
130
a9ae008f
AG
131 switch (handler->flags) {
132 case XATTR_USER:
438471b6
BP
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
79a58d1f 150 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
a9ae008f 151 goto out;
ad7a2926 152
666753c3
SF
153 if (pTcon->ses->server->ops->set_EA)
154 rc = pTcon->ses->server->ops->set_EA(xid, pTcon,
a9ae008f 155 full_path, name, value, (__u16)size,
5517554e 156 cifs_sb->local_nls, cifs_sb);
a9ae008f 157 break;
1da177e4 158
438471b6 159 case XATTR_CIFS_ACL:
3970acf7
BP
160 case XATTR_CIFS_NTSD:
161 case XATTR_CIFS_NTSD_FULL: {
b0f8ef20 162 struct cifs_ntsd *pacl;
a9ae008f
AG
163
164 if (!value)
165 goto out;
166 pacl = kmalloc(size, GFP_KERNEL);
b73b9a4b 167 if (!pacl) {
b73b9a4b
SF
168 rc = -ENOMEM;
169 } else {
a9ae008f 170 memcpy(pacl, value, size);
3970acf7
BP
171 if (pTcon->ses->server->ops->set_acl) {
172 int aclflags = 0;
438471b6 173 rc = 0;
3970acf7
BP
174
175 switch (handler->flags) {
176 case XATTR_CIFS_NTSD_FULL:
177 aclflags = (CIFS_ACL_OWNER |
dd5a927e 178 CIFS_ACL_GROUP |
3970acf7
BP
179 CIFS_ACL_DACL |
180 CIFS_ACL_SACL);
181 break;
182 case XATTR_CIFS_NTSD:
183 aclflags = (CIFS_ACL_OWNER |
dd5a927e 184 CIFS_ACL_GROUP |
3970acf7
BP
185 CIFS_ACL_DACL);
186 break;
187 case XATTR_CIFS_ACL:
188 default:
189 aclflags = CIFS_ACL_DACL;
438471b6 190 }
3970acf7
BP
191
192 rc = pTcon->ses->server->ops->set_acl(pacl,
193 size, inode, full_path, aclflags);
438471b6 194 } else {
83e3bc23 195 rc = -EOPNOTSUPP;
438471b6 196 }
b73b9a4b 197 if (rc == 0) /* force revalidate of the inode */
59301226 198 CIFS_I(inode)->time = 0;
b73b9a4b 199 kfree(pacl);
b0f8ef20 200 }
a9ae008f
AG
201 break;
202 }
1da177e4
LT
203 }
204
a9ae008f 205out:
f6a9bc33 206 free_dentry_path(page);
6d5786a3 207 free_xid(xid);
7ffec372 208 cifs_put_tlink(tlink);
1da177e4
LT
209 return rc;
210}
211
a958fff2
SF
212static int cifs_attrib_get(struct dentry *dentry,
213 struct inode *inode, void *value,
214 size_t size)
215{
216 ssize_t rc;
217 __u32 *pattribute;
218
219 rc = cifs_revalidate_dentry_attr(dentry);
220
221 if (rc)
222 return rc;
223
224 if ((value == NULL) || (size == 0))
225 return sizeof(__u32);
226 else if (size < sizeof(__u32))
227 return -ERANGE;
228
229 /* return dos attributes as pseudo xattr */
230 pattribute = (__u32 *)value;
231 *pattribute = CIFS_I(inode)->cifsAttrs;
232
233 return sizeof(__u32);
234}
235
66098044
SF
236static int cifs_creation_time_get(struct dentry *dentry, struct inode *inode,
237 void *value, size_t size)
238{
239 ssize_t rc;
438471b6 240 __u64 *pcreatetime;
66098044
SF
241
242 rc = cifs_revalidate_dentry_attr(dentry);
243 if (rc)
244 return rc;
245
246 if ((value == NULL) || (size == 0))
247 return sizeof(__u64);
248 else if (size < sizeof(__u64))
249 return -ERANGE;
250
251 /* return dos attributes as pseudo xattr */
252 pcreatetime = (__u64 *)value;
253 *pcreatetime = CIFS_I(inode)->createtime;
254 return sizeof(__u64);
66098044
SF
255}
256
a958fff2 257
a9ae008f
AG
258static int cifs_xattr_get(const struct xattr_handler *handler,
259 struct dentry *dentry, struct inode *inode,
260 const char *name, void *value, size_t size)
1da177e4
LT
261{
262 ssize_t rc = -EOPNOTSUPP;
6d5786a3 263 unsigned int xid;
a9ae008f 264 struct super_block *sb = dentry->d_sb;
5fdccfef 265 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
7ffec372 266 struct tcon_link *tlink;
96daf2b0 267 struct cifs_tcon *pTcon;
8e33cf20 268 const char *full_path;
f6a9bc33 269 void *page;
1da177e4 270
7ffec372
JL
271 tlink = cifs_sb_tlink(cifs_sb);
272 if (IS_ERR(tlink))
273 return PTR_ERR(tlink);
274 pTcon = tlink_tcon(tlink);
275
6d5786a3 276 xid = get_xid();
f6a9bc33 277 page = alloc_dentry_path();
1da177e4 278
f6a9bc33
AV
279 full_path = build_path_from_dentry(dentry, page);
280 if (IS_ERR(full_path)) {
281 rc = PTR_ERR(full_path);
a9ae008f 282 goto out;
1da177e4 283 }
a958fff2 284
1da177e4 285 /* return alt name if available as pseudo attr */
a9ae008f
AG
286 switch (handler->flags) {
287 case XATTR_USER:
a958fff2 288 cifs_dbg(FYI, "%s:querying user xattr %s\n", __func__, name);
c4f7173a
SF
289 if ((strcmp(name, CIFS_XATTR_ATTRIB) == 0) ||
290 (strcmp(name, SMB3_XATTR_ATTRIB) == 0)) {
a958fff2
SF
291 rc = cifs_attrib_get(dentry, inode, value, size);
292 break;
c4f7173a
SF
293 } else if ((strcmp(name, CIFS_XATTR_CREATETIME) == 0) ||
294 (strcmp(name, SMB3_XATTR_CREATETIME) == 0)) {
66098044
SF
295 rc = cifs_creation_time_get(dentry, inode, value, size);
296 break;
a958fff2
SF
297 }
298
79a58d1f 299 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
a9ae008f 300 goto out;
1da177e4 301
666753c3
SF
302 if (pTcon->ses->server->ops->query_all_EAs)
303 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
67b4c889 304 full_path, name, value, size, cifs_sb);
a9ae008f 305 break;
1da177e4 306
438471b6 307 case XATTR_CIFS_ACL:
3970acf7
BP
308 case XATTR_CIFS_NTSD:
309 case XATTR_CIFS_NTSD_FULL: {
310 /*
311 * fetch owner, DACL, and SACL if asked for full descriptor,
312 * fetch owner and DACL otherwise
313 */
9541b813 314 u32 acllen, extra_info;
a9ae008f
AG
315 struct cifs_ntsd *pacl;
316
317 if (pTcon->ses->server->ops->get_acl == NULL)
318 goto out; /* rc already EOPNOTSUPP */
319
3970acf7 320 if (handler->flags == XATTR_CIFS_NTSD_FULL) {
9541b813 321 extra_info = SACL_SECINFO;
3970acf7 322 } else {
9541b813 323 extra_info = 0;
3970acf7 324 }
a9ae008f 325 pacl = pTcon->ses->server->ops->get_acl(cifs_sb,
9541b813 326 inode, full_path, &acllen, extra_info);
a9ae008f
AG
327 if (IS_ERR(pacl)) {
328 rc = PTR_ERR(pacl);
329 cifs_dbg(VFS, "%s: error %zd getting sec desc\n",
330 __func__, rc);
331 } else {
332 if (value) {
333 if (acllen > size)
334 acllen = -ERANGE;
335 else
336 memcpy(value, pacl, acllen);
337 }
338 rc = acllen;
339 kfree(pacl);
340 }
a9ae008f
AG
341 break;
342 }
a9ae008f 343 }
1da177e4 344
79a58d1f 345 /* We could add an additional check for streams ie
1da177e4 346 if proc/fs/cifs/streamstoxattr is set then
79a58d1f 347 search server for EAs or streams to
1da177e4
LT
348 returns as xattrs */
349
79a58d1f
SF
350 if (rc == -EINVAL)
351 rc = -EOPNOTSUPP;
1da177e4 352
a9ae008f 353out:
f6a9bc33 354 free_dentry_path(page);
6d5786a3 355 free_xid(xid);
7ffec372 356 cifs_put_tlink(tlink);
1da177e4
LT
357 return rc;
358}
359
79a58d1f 360ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
1da177e4
LT
361{
362 ssize_t rc = -EOPNOTSUPP;
6d5786a3 363 unsigned int xid;
5fdccfef 364 struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
7ffec372 365 struct tcon_link *tlink;
96daf2b0 366 struct cifs_tcon *pTcon;
8e33cf20 367 const char *full_path;
f6a9bc33 368 void *page;
1da177e4 369
087f757b
SF
370 if (unlikely(cifs_forced_shutdown(cifs_sb)))
371 return -EIO;
372
79a58d1f 373 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
ea4c07d7
SF
374 return -EOPNOTSUPP;
375
7ffec372
JL
376 tlink = cifs_sb_tlink(cifs_sb);
377 if (IS_ERR(tlink))
378 return PTR_ERR(tlink);
379 pTcon = tlink_tcon(tlink);
380
6d5786a3 381 xid = get_xid();
f6a9bc33 382 page = alloc_dentry_path();
ea4c07d7 383
f6a9bc33
AV
384 full_path = build_path_from_dentry(direntry, page);
385 if (IS_ERR(full_path)) {
386 rc = PTR_ERR(full_path);
7ffec372 387 goto list_ea_exit;
1da177e4
LT
388 }
389 /* return dos attributes as pseudo xattr */
390 /* return alt name if available as pseudo attr */
391
392 /* if proc/fs/cifs/streamstoxattr is set then
79a58d1f 393 search server for EAs or streams to
1da177e4 394 returns as xattrs */
1da177e4 395
666753c3
SF
396 if (pTcon->ses->server->ops->query_all_EAs)
397 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
67b4c889 398 full_path, NULL, data, buf_size, cifs_sb);
7ffec372 399list_ea_exit:
f6a9bc33 400 free_dentry_path(page);
6d5786a3 401 free_xid(xid);
7ffec372 402 cifs_put_tlink(tlink);
1da177e4
LT
403 return rc;
404}
a9ae008f
AG
405
406static const struct xattr_handler cifs_user_xattr_handler = {
407 .prefix = XATTR_USER_PREFIX,
408 .flags = XATTR_USER,
409 .get = cifs_xattr_get,
410 .set = cifs_xattr_set,
411};
412
413/* os2.* attributes are treated like user.* attributes */
414static const struct xattr_handler cifs_os2_xattr_handler = {
415 .prefix = XATTR_OS2_PREFIX,
416 .flags = XATTR_USER,
417 .get = cifs_xattr_get,
418 .set = cifs_xattr_set,
419};
420
421static const struct xattr_handler cifs_cifs_acl_xattr_handler = {
422 .name = CIFS_XATTR_CIFS_ACL,
423 .flags = XATTR_CIFS_ACL,
424 .get = cifs_xattr_get,
425 .set = cifs_xattr_set,
426};
427
c4f7173a
SF
428/*
429 * Although this is just an alias for the above, need to move away from
430 * confusing users and using the 20 year old term 'cifs' when it is no
431 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
432 * SMB3 and later are highly secure.
433 */
434static const struct xattr_handler smb3_acl_xattr_handler = {
435 .name = SMB3_XATTR_CIFS_ACL,
436 .flags = XATTR_CIFS_ACL,
437 .get = cifs_xattr_get,
438 .set = cifs_xattr_set,
439};
440
438471b6
BP
441static const struct xattr_handler cifs_cifs_ntsd_xattr_handler = {
442 .name = CIFS_XATTR_CIFS_NTSD,
443 .flags = XATTR_CIFS_NTSD,
444 .get = cifs_xattr_get,
445 .set = cifs_xattr_set,
446};
447
448/*
449 * Although this is just an alias for the above, need to move away from
450 * confusing users and using the 20 year old term 'cifs' when it is no
451 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
452 * SMB3 and later are highly secure.
453 */
454static const struct xattr_handler smb3_ntsd_xattr_handler = {
455 .name = SMB3_XATTR_CIFS_NTSD,
456 .flags = XATTR_CIFS_NTSD,
457 .get = cifs_xattr_get,
458 .set = cifs_xattr_set,
459};
460
3970acf7
BP
461static const struct xattr_handler cifs_cifs_ntsd_full_xattr_handler = {
462 .name = CIFS_XATTR_CIFS_NTSD_FULL,
463 .flags = XATTR_CIFS_NTSD_FULL,
464 .get = cifs_xattr_get,
465 .set = cifs_xattr_set,
466};
467
468/*
469 * Although this is just an alias for the above, need to move away from
470 * confusing users and using the 20 year old term 'cifs' when it is no
471 * longer secure and was replaced by SMB2/SMB3 a long time ago, and
472 * SMB3 and later are highly secure.
473 */
474static const struct xattr_handler smb3_ntsd_full_xattr_handler = {
475 .name = SMB3_XATTR_CIFS_NTSD_FULL,
476 .flags = XATTR_CIFS_NTSD_FULL,
477 .get = cifs_xattr_get,
478 .set = cifs_xattr_set,
479};
480
a9ae008f
AG
481const struct xattr_handler *cifs_xattr_handlers[] = {
482 &cifs_user_xattr_handler,
483 &cifs_os2_xattr_handler,
484 &cifs_cifs_acl_xattr_handler,
c4f7173a 485 &smb3_acl_xattr_handler, /* alias for above since avoiding "cifs" */
438471b6
BP
486 &cifs_cifs_ntsd_xattr_handler,
487 &smb3_ntsd_xattr_handler, /* alias for above since avoiding "cifs" */
3970acf7
BP
488 &cifs_cifs_ntsd_full_xattr_handler,
489 &smb3_ntsd_full_xattr_handler, /* alias for above since avoiding "cifs" */
a9ae008f
AG
490 NULL
491};