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 unsigned 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 = get_xid();
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 cifs_dbg(FYI, "Null xattr names not supported\n");
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 cifs_dbg(FYI,
75 "illegal xattr request %s (only user namespace supported)\n",
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 free_xid(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 unsigned 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 = get_xid();
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 cifs_dbg(FYI, "size of EA value too large\n");
138 rc = -EOPNOTSUPP;
139 goto set_ea_exit;
140 }
141
142 if (ea_name == NULL) {
143 cifs_dbg(FYI, "Null xattr names not supported\n");
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 cifs_dbg(FYI, "attempt to set cifs inode metadata\n");
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 rc = -ENOMEM;
171 } else {
172 memcpy(pacl, ea_value, value_size);
173 rc = set_cifs_acl(pacl, value_size,
174 direntry->d_inode, full_path, CIFS_ACL_DACL);
175 if (rc == 0) /* force revalidate of the inode */
176 CIFS_I(direntry->d_inode)->time = 0;
177 kfree(pacl);
178 }
179 #else
180 cifs_dbg(FYI, "Set CIFS ACL not supported yet\n");
181 #endif /* CONFIG_CIFS_ACL */
182 } else {
183 int temp;
184 temp = strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
185 strlen(POSIX_ACL_XATTR_ACCESS));
186 if (temp == 0) {
187 #ifdef CONFIG_CIFS_POSIX
188 if (sb->s_flags & MS_POSIXACL)
189 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
190 ea_value, (const int)value_size,
191 ACL_TYPE_ACCESS, cifs_sb->local_nls,
192 cifs_sb->mnt_cifs_flags &
193 CIFS_MOUNT_MAP_SPECIAL_CHR);
194 cifs_dbg(FYI, "set POSIX ACL rc %d\n", rc);
195 #else
196 cifs_dbg(FYI, "set POSIX ACL not supported\n");
197 #endif
198 } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
199 strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
200 #ifdef CONFIG_CIFS_POSIX
201 if (sb->s_flags & MS_POSIXACL)
202 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
203 ea_value, (const int)value_size,
204 ACL_TYPE_DEFAULT, cifs_sb->local_nls,
205 cifs_sb->mnt_cifs_flags &
206 CIFS_MOUNT_MAP_SPECIAL_CHR);
207 cifs_dbg(FYI, "set POSIX default ACL rc %d\n", rc);
208 #else
209 cifs_dbg(FYI, "set default POSIX ACL not supported\n");
210 #endif
211 } else {
212 cifs_dbg(FYI, "illegal xattr request %s (only user namespace supported)\n",
213 ea_name);
214 /* BB what if no namespace prefix? */
215 /* Should we just pass them to server, except for
216 system and perhaps security prefixes? */
217 }
218 }
219
220 set_ea_exit:
221 kfree(full_path);
222 free_xid(xid);
223 cifs_put_tlink(tlink);
224 #endif
225 return rc;
226 }
227
cifs_getxattr(struct dentry * direntry,const char * ea_name,void * ea_value,size_t buf_size)228 ssize_t cifs_getxattr(struct dentry *direntry, const char *ea_name,
229 void *ea_value, size_t buf_size)
230 {
231 ssize_t rc = -EOPNOTSUPP;
232 #ifdef CONFIG_CIFS_XATTR
233 unsigned int xid;
234 struct cifs_sb_info *cifs_sb;
235 struct tcon_link *tlink;
236 struct cifs_tcon *pTcon;
237 struct super_block *sb;
238 char *full_path;
239
240 if (direntry == NULL)
241 return -EIO;
242 if (direntry->d_inode == NULL)
243 return -EIO;
244 sb = direntry->d_inode->i_sb;
245 if (sb == NULL)
246 return -EIO;
247
248 cifs_sb = CIFS_SB(sb);
249 tlink = cifs_sb_tlink(cifs_sb);
250 if (IS_ERR(tlink))
251 return PTR_ERR(tlink);
252 pTcon = tlink_tcon(tlink);
253
254 xid = get_xid();
255
256 full_path = build_path_from_dentry(direntry);
257 if (full_path == NULL) {
258 rc = -ENOMEM;
259 goto get_ea_exit;
260 }
261 /* return dos attributes as pseudo xattr */
262 /* return alt name if available as pseudo attr */
263 if (ea_name == NULL) {
264 cifs_dbg(FYI, "Null xattr names not supported\n");
265 } else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
266 == 0) {
267 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
268 goto get_ea_exit;
269
270 if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0) {
271 cifs_dbg(FYI, "attempt to query cifs inode metadata\n");
272 /* revalidate/getattr then populate from inode */
273 } /* BB add else when above is implemented */
274 ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
275 rc = CIFSSMBQAllEAs(xid, pTcon, full_path, ea_name, ea_value,
276 buf_size, cifs_sb->local_nls,
277 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
278 } else if (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
279 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
280 goto get_ea_exit;
281
282 ea_name += XATTR_OS2_PREFIX_LEN; /* skip past os2. prefix */
283 rc = CIFSSMBQAllEAs(xid, pTcon, full_path, ea_name, ea_value,
284 buf_size, cifs_sb->local_nls,
285 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
286 } else if (strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
287 strlen(POSIX_ACL_XATTR_ACCESS)) == 0) {
288 #ifdef CONFIG_CIFS_POSIX
289 if (sb->s_flags & MS_POSIXACL)
290 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
291 ea_value, buf_size, ACL_TYPE_ACCESS,
292 cifs_sb->local_nls,
293 cifs_sb->mnt_cifs_flags &
294 CIFS_MOUNT_MAP_SPECIAL_CHR);
295 #else
296 cifs_dbg(FYI, "Query POSIX ACL not supported yet\n");
297 #endif /* CONFIG_CIFS_POSIX */
298 } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
299 strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
300 #ifdef CONFIG_CIFS_POSIX
301 if (sb->s_flags & MS_POSIXACL)
302 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
303 ea_value, buf_size, ACL_TYPE_DEFAULT,
304 cifs_sb->local_nls,
305 cifs_sb->mnt_cifs_flags &
306 CIFS_MOUNT_MAP_SPECIAL_CHR);
307 #else
308 cifs_dbg(FYI, "Query POSIX default ACL not supported yet\n");
309 #endif /* CONFIG_CIFS_POSIX */
310 } else if (strncmp(ea_name, CIFS_XATTR_CIFS_ACL,
311 strlen(CIFS_XATTR_CIFS_ACL)) == 0) {
312 #ifdef CONFIG_CIFS_ACL
313 u32 acllen;
314 struct cifs_ntsd *pacl;
315
316 pacl = get_cifs_acl(cifs_sb, direntry->d_inode,
317 full_path, &acllen);
318 if (IS_ERR(pacl)) {
319 rc = PTR_ERR(pacl);
320 cifs_dbg(VFS, "%s: error %zd getting sec desc\n",
321 __func__, rc);
322 } else {
323 if (ea_value) {
324 if (acllen > buf_size)
325 acllen = -ERANGE;
326 else
327 memcpy(ea_value, pacl, acllen);
328 }
329 rc = acllen;
330 kfree(pacl);
331 }
332 #else
333 cifs_dbg(FYI, "Query CIFS ACL not supported yet\n");
334 #endif /* CONFIG_CIFS_ACL */
335 } else if (strncmp(ea_name,
336 XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) {
337 cifs_dbg(FYI, "Trusted xattr namespace not supported yet\n");
338 } else if (strncmp(ea_name,
339 XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) == 0) {
340 cifs_dbg(FYI, "Security xattr namespace not supported yet\n");
341 } else
342 cifs_dbg(FYI,
343 "illegal xattr request %s (only user namespace supported)\n",
344 ea_name);
345
346 /* We could add an additional check for streams ie
347 if proc/fs/cifs/streamstoxattr is set then
348 search server for EAs or streams to
349 returns as xattrs */
350
351 if (rc == -EINVAL)
352 rc = -EOPNOTSUPP;
353
354 get_ea_exit:
355 kfree(full_path);
356 free_xid(xid);
357 cifs_put_tlink(tlink);
358 #endif
359 return rc;
360 }
361
cifs_listxattr(struct dentry * direntry,char * data,size_t buf_size)362 ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
363 {
364 ssize_t rc = -EOPNOTSUPP;
365 #ifdef CONFIG_CIFS_XATTR
366 unsigned int xid;
367 struct cifs_sb_info *cifs_sb;
368 struct tcon_link *tlink;
369 struct cifs_tcon *pTcon;
370 struct super_block *sb;
371 char *full_path;
372
373 if (direntry == NULL)
374 return -EIO;
375 if (direntry->d_inode == NULL)
376 return -EIO;
377 sb = direntry->d_inode->i_sb;
378 if (sb == NULL)
379 return -EIO;
380
381 cifs_sb = CIFS_SB(sb);
382 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
383 return -EOPNOTSUPP;
384
385 tlink = cifs_sb_tlink(cifs_sb);
386 if (IS_ERR(tlink))
387 return PTR_ERR(tlink);
388 pTcon = tlink_tcon(tlink);
389
390 xid = get_xid();
391
392 full_path = build_path_from_dentry(direntry);
393 if (full_path == NULL) {
394 rc = -ENOMEM;
395 goto list_ea_exit;
396 }
397 /* return dos attributes as pseudo xattr */
398 /* return alt name if available as pseudo attr */
399
400 /* if proc/fs/cifs/streamstoxattr is set then
401 search server for EAs or streams to
402 returns as xattrs */
403 rc = CIFSSMBQAllEAs(xid, pTcon, full_path, NULL, data,
404 buf_size, cifs_sb->local_nls,
405 cifs_sb->mnt_cifs_flags &
406 CIFS_MOUNT_MAP_SPECIAL_CHR);
407
408 list_ea_exit:
409 kfree(full_path);
410 free_xid(xid);
411 cifs_put_tlink(tlink);
412 #endif
413 return rc;
414 }
415