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
32 #define MAX_EA_VALUE_SIZE 65535
33 #define CIFS_XATTR_DOS_ATTRIB "user.DosAttrib"
34 #define CIFS_XATTR_CIFS_ACL "system.cifs_acl"
35
36 /* BB need to add server (Samba e.g) support for security and trusted prefix */
37
cifs_removexattr(struct dentry * direntry,const char * ea_name)38 int cifs_removexattr(struct dentry *direntry, const char *ea_name)
39 {
40 int rc = -EOPNOTSUPP;
41 #ifdef CONFIG_CIFS_XATTR
42 int xid;
43 struct cifs_sb_info *cifs_sb;
44 struct tcon_link *tlink;
45 struct cifs_tcon *pTcon;
46 struct super_block *sb;
47 char *full_path = NULL;
48
49 if (direntry == NULL)
50 return -EIO;
51 if (direntry->d_inode == NULL)
52 return -EIO;
53 sb = direntry->d_inode->i_sb;
54 if (sb == NULL)
55 return -EIO;
56
57 cifs_sb = CIFS_SB(sb);
58 tlink = cifs_sb_tlink(cifs_sb);
59 if (IS_ERR(tlink))
60 return PTR_ERR(tlink);
61 pTcon = tlink_tcon(tlink);
62
63 xid = GetXid();
64
65 full_path = build_path_from_dentry(direntry);
66 if (full_path == NULL) {
67 rc = -ENOMEM;
68 goto remove_ea_exit;
69 }
70 if (ea_name == NULL) {
71 cFYI(1, "Null xattr names not supported");
72 } else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
73 && (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN))) {
74 cFYI(1,
75 "illegal xattr request %s (only user namespace supported)",
76 ea_name);
77 /* BB what if no namespace prefix? */
78 /* Should we just pass them to server, except for
79 system and perhaps security prefixes? */
80 } else {
81 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
82 goto remove_ea_exit;
83
84 ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
85 rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, NULL,
86 (__u16)0, cifs_sb->local_nls,
87 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
88 }
89 remove_ea_exit:
90 kfree(full_path);
91 FreeXid(xid);
92 cifs_put_tlink(tlink);
93 #endif
94 return rc;
95 }
96
cifs_setxattr(struct dentry * direntry,const char * ea_name,const void * ea_value,size_t value_size,int flags)97 int cifs_setxattr(struct dentry *direntry, const char *ea_name,
98 const void *ea_value, size_t value_size, int flags)
99 {
100 int rc = -EOPNOTSUPP;
101 #ifdef CONFIG_CIFS_XATTR
102 int xid;
103 struct cifs_sb_info *cifs_sb;
104 struct tcon_link *tlink;
105 struct cifs_tcon *pTcon;
106 struct super_block *sb;
107 char *full_path;
108
109 if (direntry == NULL)
110 return -EIO;
111 if (direntry->d_inode == NULL)
112 return -EIO;
113 sb = direntry->d_inode->i_sb;
114 if (sb == NULL)
115 return -EIO;
116
117 cifs_sb = CIFS_SB(sb);
118 tlink = cifs_sb_tlink(cifs_sb);
119 if (IS_ERR(tlink))
120 return PTR_ERR(tlink);
121 pTcon = tlink_tcon(tlink);
122
123 xid = GetXid();
124
125 full_path = build_path_from_dentry(direntry);
126 if (full_path == NULL) {
127 rc = -ENOMEM;
128 goto set_ea_exit;
129 }
130 /* return dos attributes as pseudo xattr */
131 /* return alt name if available as pseudo attr */
132
133 /* if proc/fs/cifs/streamstoxattr is set then
134 search server for EAs or streams to
135 returns as xattrs */
136 if (value_size > MAX_EA_VALUE_SIZE) {
137 cFYI(1, "size of EA value too large");
138 rc = -EOPNOTSUPP;
139 goto set_ea_exit;
140 }
141
142 if (ea_name == NULL) {
143 cFYI(1, "Null xattr names not supported");
144 } else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
145 == 0) {
146 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
147 goto set_ea_exit;
148 if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0)
149 cFYI(1, "attempt to set cifs inode metadata");
150
151 ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
152 rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
153 (__u16)value_size, cifs_sb->local_nls,
154 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
155 } else if (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN)
156 == 0) {
157 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
158 goto set_ea_exit;
159
160 ea_name += XATTR_OS2_PREFIX_LEN; /* skip past os2. prefix */
161 rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
162 (__u16)value_size, cifs_sb->local_nls,
163 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
164 } else if (strncmp(ea_name, CIFS_XATTR_CIFS_ACL,
165 strlen(CIFS_XATTR_CIFS_ACL)) == 0) {
166 #ifdef CONFIG_CIFS_ACL
167 struct cifs_ntsd *pacl;
168 pacl = kmalloc(value_size, GFP_KERNEL);
169 if (!pacl) {
170 cFYI(1, "%s: Can't allocate memory for ACL",
171 __func__);
172 rc = -ENOMEM;
173 } else {
174 memcpy(pacl, ea_value, value_size);
175 rc = set_cifs_acl(pacl, value_size,
176 direntry->d_inode, full_path, CIFS_ACL_DACL);
177 if (rc == 0) /* force revalidate of the inode */
178 CIFS_I(direntry->d_inode)->time = 0;
179 kfree(pacl);
180 }
181 #else
182 cFYI(1, "Set CIFS ACL not supported yet");
183 #endif /* CONFIG_CIFS_ACL */
184 } else {
185 int temp;
186 temp = strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
187 strlen(POSIX_ACL_XATTR_ACCESS));
188 if (temp == 0) {
189 #ifdef CONFIG_CIFS_POSIX
190 if (sb->s_flags & MS_POSIXACL)
191 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
192 ea_value, (const int)value_size,
193 ACL_TYPE_ACCESS, cifs_sb->local_nls,
194 cifs_sb->mnt_cifs_flags &
195 CIFS_MOUNT_MAP_SPECIAL_CHR);
196 cFYI(1, "set POSIX ACL rc %d", rc);
197 #else
198 cFYI(1, "set POSIX ACL not supported");
199 #endif
200 } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
201 strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
202 #ifdef CONFIG_CIFS_POSIX
203 if (sb->s_flags & MS_POSIXACL)
204 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
205 ea_value, (const int)value_size,
206 ACL_TYPE_DEFAULT, cifs_sb->local_nls,
207 cifs_sb->mnt_cifs_flags &
208 CIFS_MOUNT_MAP_SPECIAL_CHR);
209 cFYI(1, "set POSIX default ACL rc %d", rc);
210 #else
211 cFYI(1, "set default POSIX ACL not supported");
212 #endif
213 } else {
214 cFYI(1, "illegal xattr request %s (only user namespace"
215 " supported)", ea_name);
216 /* BB what if no namespace prefix? */
217 /* Should we just pass them to server, except for
218 system and perhaps security prefixes? */
219 }
220 }
221
222 set_ea_exit:
223 kfree(full_path);
224 FreeXid(xid);
225 cifs_put_tlink(tlink);
226 #endif
227 return rc;
228 }
229
cifs_getxattr(struct dentry * direntry,const char * ea_name,void * ea_value,size_t buf_size)230 ssize_t cifs_getxattr(struct dentry *direntry, const char *ea_name,
231 void *ea_value, size_t buf_size)
232 {
233 ssize_t rc = -EOPNOTSUPP;
234 #ifdef CONFIG_CIFS_XATTR
235 int xid;
236 struct cifs_sb_info *cifs_sb;
237 struct tcon_link *tlink;
238 struct cifs_tcon *pTcon;
239 struct super_block *sb;
240 char *full_path;
241
242 if (direntry == NULL)
243 return -EIO;
244 if (direntry->d_inode == NULL)
245 return -EIO;
246 sb = direntry->d_inode->i_sb;
247 if (sb == NULL)
248 return -EIO;
249
250 cifs_sb = CIFS_SB(sb);
251 tlink = cifs_sb_tlink(cifs_sb);
252 if (IS_ERR(tlink))
253 return PTR_ERR(tlink);
254 pTcon = tlink_tcon(tlink);
255
256 xid = GetXid();
257
258 full_path = build_path_from_dentry(direntry);
259 if (full_path == NULL) {
260 rc = -ENOMEM;
261 goto get_ea_exit;
262 }
263 /* return dos attributes as pseudo xattr */
264 /* return alt name if available as pseudo attr */
265 if (ea_name == NULL) {
266 cFYI(1, "Null xattr names not supported");
267 } else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
268 == 0) {
269 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
270 goto get_ea_exit;
271
272 if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0) {
273 cFYI(1, "attempt to query cifs inode metadata");
274 /* revalidate/getattr then populate from inode */
275 } /* BB add else when above is implemented */
276 ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
277 rc = CIFSSMBQAllEAs(xid, pTcon, full_path, ea_name, ea_value,
278 buf_size, cifs_sb->local_nls,
279 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
280 } else if (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
281 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
282 goto get_ea_exit;
283
284 ea_name += XATTR_OS2_PREFIX_LEN; /* skip past os2. prefix */
285 rc = CIFSSMBQAllEAs(xid, pTcon, full_path, ea_name, ea_value,
286 buf_size, cifs_sb->local_nls,
287 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
288 } else if (strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
289 strlen(POSIX_ACL_XATTR_ACCESS)) == 0) {
290 #ifdef CONFIG_CIFS_POSIX
291 if (sb->s_flags & MS_POSIXACL)
292 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
293 ea_value, buf_size, ACL_TYPE_ACCESS,
294 cifs_sb->local_nls,
295 cifs_sb->mnt_cifs_flags &
296 CIFS_MOUNT_MAP_SPECIAL_CHR);
297 #else
298 cFYI(1, "Query POSIX ACL not supported yet");
299 #endif /* CONFIG_CIFS_POSIX */
300 } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
301 strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
302 #ifdef CONFIG_CIFS_POSIX
303 if (sb->s_flags & MS_POSIXACL)
304 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
305 ea_value, buf_size, ACL_TYPE_DEFAULT,
306 cifs_sb->local_nls,
307 cifs_sb->mnt_cifs_flags &
308 CIFS_MOUNT_MAP_SPECIAL_CHR);
309 #else
310 cFYI(1, "Query POSIX default ACL not supported yet");
311 #endif /* CONFIG_CIFS_POSIX */
312 } else if (strncmp(ea_name, CIFS_XATTR_CIFS_ACL,
313 strlen(CIFS_XATTR_CIFS_ACL)) == 0) {
314 #ifdef CONFIG_CIFS_ACL
315 u32 acllen;
316 struct cifs_ntsd *pacl;
317
318 pacl = get_cifs_acl(cifs_sb, direntry->d_inode,
319 full_path, &acllen);
320 if (IS_ERR(pacl)) {
321 rc = PTR_ERR(pacl);
322 cERROR(1, "%s: error %zd getting sec desc",
323 __func__, rc);
324 } else {
325 if (ea_value) {
326 if (acllen > buf_size)
327 acllen = -ERANGE;
328 else
329 memcpy(ea_value, pacl, acllen);
330 }
331 rc = acllen;
332 kfree(pacl);
333 }
334 #else
335 cFYI(1, "Query CIFS ACL not supported yet");
336 #endif /* CONFIG_CIFS_ACL */
337 } else if (strncmp(ea_name,
338 XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) {
339 cFYI(1, "Trusted xattr namespace not supported yet");
340 } else if (strncmp(ea_name,
341 XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) == 0) {
342 cFYI(1, "Security xattr namespace not supported yet");
343 } else
344 cFYI(1,
345 "illegal xattr request %s (only user namespace supported)",
346 ea_name);
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 get_ea_exit:
357 kfree(full_path);
358 FreeXid(xid);
359 cifs_put_tlink(tlink);
360 #endif
361 return rc;
362 }
363
cifs_listxattr(struct dentry * direntry,char * data,size_t buf_size)364 ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
365 {
366 ssize_t rc = -EOPNOTSUPP;
367 #ifdef CONFIG_CIFS_XATTR
368 int xid;
369 struct cifs_sb_info *cifs_sb;
370 struct tcon_link *tlink;
371 struct cifs_tcon *pTcon;
372 struct super_block *sb;
373 char *full_path;
374
375 if (direntry == NULL)
376 return -EIO;
377 if (direntry->d_inode == NULL)
378 return -EIO;
379 sb = direntry->d_inode->i_sb;
380 if (sb == NULL)
381 return -EIO;
382
383 cifs_sb = CIFS_SB(sb);
384 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
385 return -EOPNOTSUPP;
386
387 tlink = cifs_sb_tlink(cifs_sb);
388 if (IS_ERR(tlink))
389 return PTR_ERR(tlink);
390 pTcon = tlink_tcon(tlink);
391
392 xid = GetXid();
393
394 full_path = build_path_from_dentry(direntry);
395 if (full_path == NULL) {
396 rc = -ENOMEM;
397 goto list_ea_exit;
398 }
399 /* return dos attributes as pseudo xattr */
400 /* return alt name if available as pseudo attr */
401
402 /* if proc/fs/cifs/streamstoxattr is set then
403 search server for EAs or streams to
404 returns as xattrs */
405 rc = CIFSSMBQAllEAs(xid, pTcon, full_path, NULL, data,
406 buf_size, cifs_sb->local_nls,
407 cifs_sb->mnt_cifs_flags &
408 CIFS_MOUNT_MAP_SPECIAL_CHR);
409
410 list_ea_exit:
411 kfree(full_path);
412 FreeXid(xid);
413 cifs_put_tlink(tlink);
414 #endif
415 return rc;
416 }
417