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 65535
35 #define CIFS_XATTR_DOS_ATTRIB "user.DosAttrib"
36 #define CIFS_XATTR_CIFS_ACL "system.cifs_acl"
37
38 /* BB need to add server (Samba e.g) support for security and trusted prefix */
39
cifs_removexattr(struct dentry * direntry,const char * ea_name)40 int cifs_removexattr(struct dentry *direntry, const char *ea_name)
41 {
42 int rc = -EOPNOTSUPP;
43 #ifdef CONFIG_CIFS_XATTR
44 unsigned int xid;
45 struct cifs_sb_info *cifs_sb;
46 struct tcon_link *tlink;
47 struct cifs_tcon *pTcon;
48 struct super_block *sb;
49 char *full_path = NULL;
50
51 if (direntry == NULL)
52 return -EIO;
53 if (direntry->d_inode == NULL)
54 return -EIO;
55 sb = direntry->d_inode->i_sb;
56 if (sb == NULL)
57 return -EIO;
58
59 cifs_sb = CIFS_SB(sb);
60 tlink = cifs_sb_tlink(cifs_sb);
61 if (IS_ERR(tlink))
62 return PTR_ERR(tlink);
63 pTcon = tlink_tcon(tlink);
64
65 xid = get_xid();
66
67 full_path = build_path_from_dentry(direntry);
68 if (full_path == NULL) {
69 rc = -ENOMEM;
70 goto remove_ea_exit;
71 }
72 if (ea_name == NULL) {
73 cifs_dbg(FYI, "Null xattr names not supported\n");
74 } else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
75 && (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN))) {
76 cifs_dbg(FYI,
77 "illegal xattr request %s (only user namespace supported)\n",
78 ea_name);
79 /* BB what if no namespace prefix? */
80 /* Should we just pass them to server, except for
81 system and perhaps security prefixes? */
82 } else {
83 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
84 goto remove_ea_exit;
85
86 ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
87 if (pTcon->ses->server->ops->set_EA)
88 rc = pTcon->ses->server->ops->set_EA(xid, pTcon,
89 full_path, ea_name, NULL, (__u16)0,
90 cifs_sb->local_nls, cifs_remap(cifs_sb));
91 }
92 remove_ea_exit:
93 kfree(full_path);
94 free_xid(xid);
95 cifs_put_tlink(tlink);
96 #endif
97 return rc;
98 }
99
cifs_setxattr(struct dentry * direntry,const char * ea_name,const void * ea_value,size_t value_size,int flags)100 int cifs_setxattr(struct dentry *direntry, const char *ea_name,
101 const void *ea_value, size_t value_size, int flags)
102 {
103 int rc = -EOPNOTSUPP;
104 #ifdef CONFIG_CIFS_XATTR
105 unsigned int xid;
106 struct cifs_sb_info *cifs_sb;
107 struct tcon_link *tlink;
108 struct cifs_tcon *pTcon;
109 struct super_block *sb;
110 char *full_path;
111
112 if (direntry == NULL)
113 return -EIO;
114 if (direntry->d_inode == NULL)
115 return -EIO;
116 sb = direntry->d_inode->i_sb;
117 if (sb == NULL)
118 return -EIO;
119
120 cifs_sb = CIFS_SB(sb);
121 tlink = cifs_sb_tlink(cifs_sb);
122 if (IS_ERR(tlink))
123 return PTR_ERR(tlink);
124 pTcon = tlink_tcon(tlink);
125
126 xid = get_xid();
127
128 full_path = build_path_from_dentry(direntry);
129 if (full_path == NULL) {
130 rc = -ENOMEM;
131 goto set_ea_exit;
132 }
133 /* return dos attributes as pseudo xattr */
134 /* return alt name if available as pseudo attr */
135
136 /* if proc/fs/cifs/streamstoxattr is set then
137 search server for EAs or streams to
138 returns as xattrs */
139 if (value_size > MAX_EA_VALUE_SIZE) {
140 cifs_dbg(FYI, "size of EA value too large\n");
141 rc = -EOPNOTSUPP;
142 goto set_ea_exit;
143 }
144
145 if (ea_name == NULL) {
146 cifs_dbg(FYI, "Null xattr names not supported\n");
147 } else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
148 == 0) {
149 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
150 goto set_ea_exit;
151 if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0)
152 cifs_dbg(FYI, "attempt to set cifs inode metadata\n");
153
154 ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
155 if (pTcon->ses->server->ops->set_EA)
156 rc = pTcon->ses->server->ops->set_EA(xid, pTcon,
157 full_path, ea_name, ea_value, (__u16)value_size,
158 cifs_sb->local_nls, cifs_remap(cifs_sb));
159 } else if (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN)
160 == 0) {
161 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
162 goto set_ea_exit;
163
164 ea_name += XATTR_OS2_PREFIX_LEN; /* skip past os2. prefix */
165 if (pTcon->ses->server->ops->set_EA)
166 rc = pTcon->ses->server->ops->set_EA(xid, pTcon,
167 full_path, ea_name, ea_value, (__u16)value_size,
168 cifs_sb->local_nls, cifs_remap(cifs_sb));
169 } else if (strncmp(ea_name, CIFS_XATTR_CIFS_ACL,
170 strlen(CIFS_XATTR_CIFS_ACL)) == 0) {
171 #ifdef CONFIG_CIFS_ACL
172 struct cifs_ntsd *pacl;
173 pacl = kmalloc(value_size, GFP_KERNEL);
174 if (!pacl) {
175 rc = -ENOMEM;
176 } else {
177 memcpy(pacl, ea_value, value_size);
178 if (pTcon->ses->server->ops->set_acl)
179 rc = pTcon->ses->server->ops->set_acl(pacl,
180 value_size, direntry->d_inode,
181 full_path, CIFS_ACL_DACL);
182 else
183 rc = -EOPNOTSUPP;
184 if (rc == 0) /* force revalidate of the inode */
185 CIFS_I(direntry->d_inode)->time = 0;
186 kfree(pacl);
187 }
188 #else
189 cifs_dbg(FYI, "Set CIFS ACL not supported yet\n");
190 #endif /* CONFIG_CIFS_ACL */
191 } else {
192 int temp;
193 temp = strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
194 strlen(POSIX_ACL_XATTR_ACCESS));
195 if (temp == 0) {
196 #ifdef CONFIG_CIFS_POSIX
197 if (sb->s_flags & MS_POSIXACL)
198 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
199 ea_value, (const int)value_size,
200 ACL_TYPE_ACCESS, cifs_sb->local_nls,
201 cifs_remap(cifs_sb));
202 cifs_dbg(FYI, "set POSIX ACL rc %d\n", rc);
203 #else
204 cifs_dbg(FYI, "set POSIX ACL not supported\n");
205 #endif
206 } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
207 strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
208 #ifdef CONFIG_CIFS_POSIX
209 if (sb->s_flags & MS_POSIXACL)
210 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
211 ea_value, (const int)value_size,
212 ACL_TYPE_DEFAULT, cifs_sb->local_nls,
213 cifs_remap(cifs_sb));
214 cifs_dbg(FYI, "set POSIX default ACL rc %d\n", rc);
215 #else
216 cifs_dbg(FYI, "set default POSIX ACL not supported\n");
217 #endif
218 } else {
219 cifs_dbg(FYI, "illegal xattr request %s (only user namespace supported)\n",
220 ea_name);
221 /* BB what if no namespace prefix? */
222 /* Should we just pass them to server, except for
223 system and perhaps security prefixes? */
224 }
225 }
226
227 set_ea_exit:
228 kfree(full_path);
229 free_xid(xid);
230 cifs_put_tlink(tlink);
231 #endif
232 return rc;
233 }
234
cifs_getxattr(struct dentry * direntry,const char * ea_name,void * ea_value,size_t buf_size)235 ssize_t cifs_getxattr(struct dentry *direntry, const char *ea_name,
236 void *ea_value, size_t buf_size)
237 {
238 ssize_t rc = -EOPNOTSUPP;
239 #ifdef CONFIG_CIFS_XATTR
240 unsigned int xid;
241 struct cifs_sb_info *cifs_sb;
242 struct tcon_link *tlink;
243 struct cifs_tcon *pTcon;
244 struct super_block *sb;
245 char *full_path;
246
247 if (direntry == NULL)
248 return -EIO;
249 if (direntry->d_inode == NULL)
250 return -EIO;
251 sb = direntry->d_inode->i_sb;
252 if (sb == NULL)
253 return -EIO;
254
255 cifs_sb = CIFS_SB(sb);
256 tlink = cifs_sb_tlink(cifs_sb);
257 if (IS_ERR(tlink))
258 return PTR_ERR(tlink);
259 pTcon = tlink_tcon(tlink);
260
261 xid = get_xid();
262
263 full_path = build_path_from_dentry(direntry);
264 if (full_path == NULL) {
265 rc = -ENOMEM;
266 goto get_ea_exit;
267 }
268 /* return dos attributes as pseudo xattr */
269 /* return alt name if available as pseudo attr */
270 if (ea_name == NULL) {
271 cifs_dbg(FYI, "Null xattr names not supported\n");
272 } else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
273 == 0) {
274 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
275 goto get_ea_exit;
276
277 if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0) {
278 cifs_dbg(FYI, "attempt to query cifs inode metadata\n");
279 /* revalidate/getattr then populate from inode */
280 } /* BB add else when above is implemented */
281 ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
282 if (pTcon->ses->server->ops->query_all_EAs)
283 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
284 full_path, ea_name, ea_value, buf_size,
285 cifs_sb->local_nls, cifs_remap(cifs_sb));
286 } else if (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
287 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
288 goto get_ea_exit;
289
290 ea_name += XATTR_OS2_PREFIX_LEN; /* skip past os2. prefix */
291 if (pTcon->ses->server->ops->query_all_EAs)
292 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
293 full_path, ea_name, ea_value, buf_size,
294 cifs_sb->local_nls, cifs_remap(cifs_sb));
295 } else if (strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
296 strlen(POSIX_ACL_XATTR_ACCESS)) == 0) {
297 #ifdef CONFIG_CIFS_POSIX
298 if (sb->s_flags & MS_POSIXACL)
299 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
300 ea_value, buf_size, ACL_TYPE_ACCESS,
301 cifs_sb->local_nls,
302 cifs_remap(cifs_sb));
303 #else
304 cifs_dbg(FYI, "Query POSIX ACL not supported yet\n");
305 #endif /* CONFIG_CIFS_POSIX */
306 } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
307 strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
308 #ifdef CONFIG_CIFS_POSIX
309 if (sb->s_flags & MS_POSIXACL)
310 rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
311 ea_value, buf_size, ACL_TYPE_DEFAULT,
312 cifs_sb->local_nls,
313 cifs_remap(cifs_sb));
314 #else
315 cifs_dbg(FYI, "Query POSIX default ACL not supported yet\n");
316 #endif /* CONFIG_CIFS_POSIX */
317 } else if (strncmp(ea_name, CIFS_XATTR_CIFS_ACL,
318 strlen(CIFS_XATTR_CIFS_ACL)) == 0) {
319 #ifdef CONFIG_CIFS_ACL
320 u32 acllen;
321 struct cifs_ntsd *pacl;
322
323 if (pTcon->ses->server->ops->get_acl == NULL)
324 goto get_ea_exit; /* rc already EOPNOTSUPP */
325
326 pacl = pTcon->ses->server->ops->get_acl(cifs_sb,
327 direntry->d_inode, full_path, &acllen);
328 if (IS_ERR(pacl)) {
329 rc = PTR_ERR(pacl);
330 cifs_dbg(VFS, "%s: error %zd getting sec desc\n",
331 __func__, rc);
332 } else {
333 if (ea_value) {
334 if (acllen > buf_size)
335 acllen = -ERANGE;
336 else
337 memcpy(ea_value, pacl, acllen);
338 }
339 rc = acllen;
340 kfree(pacl);
341 }
342 #else
343 cifs_dbg(FYI, "Query CIFS ACL not supported yet\n");
344 #endif /* CONFIG_CIFS_ACL */
345 } else if (strncmp(ea_name,
346 XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) {
347 cifs_dbg(FYI, "Trusted xattr namespace not supported yet\n");
348 } else if (strncmp(ea_name,
349 XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) == 0) {
350 cifs_dbg(FYI, "Security xattr namespace not supported yet\n");
351 } else
352 cifs_dbg(FYI,
353 "illegal xattr request %s (only user namespace supported)\n",
354 ea_name);
355
356 /* We could add an additional check for streams ie
357 if proc/fs/cifs/streamstoxattr is set then
358 search server for EAs or streams to
359 returns as xattrs */
360
361 if (rc == -EINVAL)
362 rc = -EOPNOTSUPP;
363
364 get_ea_exit:
365 kfree(full_path);
366 free_xid(xid);
367 cifs_put_tlink(tlink);
368 #endif
369 return rc;
370 }
371
cifs_listxattr(struct dentry * direntry,char * data,size_t buf_size)372 ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
373 {
374 ssize_t rc = -EOPNOTSUPP;
375 #ifdef CONFIG_CIFS_XATTR
376 unsigned int xid;
377 struct cifs_sb_info *cifs_sb;
378 struct tcon_link *tlink;
379 struct cifs_tcon *pTcon;
380 struct super_block *sb;
381 char *full_path;
382
383 if (direntry == NULL)
384 return -EIO;
385 if (direntry->d_inode == NULL)
386 return -EIO;
387 sb = direntry->d_inode->i_sb;
388 if (sb == NULL)
389 return -EIO;
390
391 cifs_sb = CIFS_SB(sb);
392 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
393 return -EOPNOTSUPP;
394
395 tlink = cifs_sb_tlink(cifs_sb);
396 if (IS_ERR(tlink))
397 return PTR_ERR(tlink);
398 pTcon = tlink_tcon(tlink);
399
400 xid = get_xid();
401
402 full_path = build_path_from_dentry(direntry);
403 if (full_path == NULL) {
404 rc = -ENOMEM;
405 goto list_ea_exit;
406 }
407 /* return dos attributes as pseudo xattr */
408 /* return alt name if available as pseudo attr */
409
410 /* if proc/fs/cifs/streamstoxattr is set then
411 search server for EAs or streams to
412 returns as xattrs */
413
414 if (pTcon->ses->server->ops->query_all_EAs)
415 rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
416 full_path, NULL, data, buf_size,
417 cifs_sb->local_nls, cifs_remap(cifs_sb));
418 list_ea_exit:
419 kfree(full_path);
420 free_xid(xid);
421 cifs_put_tlink(tlink);
422 #endif
423 return rc;
424 }
425