Linux 2.6.31-rc6
[linux-2.6] / fs / cifs / xattr.c
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 "cifsfs.h"
25 #include "cifspdu.h"
26 #include "cifsglob.h"
27 #include "cifsproto.h"
28 #include "cifs_debug.h"
29
30 #define MAX_EA_VALUE_SIZE 65535
31 #define CIFS_XATTR_DOS_ATTRIB "user.DosAttrib"
32 #define CIFS_XATTR_USER_PREFIX "user."
33 #define CIFS_XATTR_SYSTEM_PREFIX "system."
34 #define CIFS_XATTR_OS2_PREFIX "os2."
35 #define CIFS_XATTR_SECURITY_PREFIX ".security"
36 #define CIFS_XATTR_TRUSTED_PREFIX "trusted."
37 #define XATTR_TRUSTED_PREFIX_LEN  8
38 #define XATTR_SECURITY_PREFIX_LEN 9
39 /* BB need to add server (Samba e.g) support for security and trusted prefix */
40
41
42
43 int cifs_removexattr(struct dentry *direntry, const char *ea_name)
44 {
45         int rc = -EOPNOTSUPP;
46 #ifdef CONFIG_CIFS_XATTR
47         int xid;
48         struct cifs_sb_info *cifs_sb;
49         struct cifsTconInfo *pTcon;
50         struct super_block *sb;
51         char *full_path;
52
53         if (direntry == NULL)
54                 return -EIO;
55         if (direntry->d_inode == NULL)
56                 return -EIO;
57         sb = direntry->d_inode->i_sb;
58         if (sb == NULL)
59                 return -EIO;
60         xid = GetXid();
61
62         cifs_sb = CIFS_SB(sb);
63         pTcon = cifs_sb->tcon;
64
65         full_path = build_path_from_dentry(direntry);
66         if (full_path == NULL) {
67                 rc = -ENOMEM;
68                 FreeXid(xid);
69                 return rc;
70         }
71         if (ea_name == NULL) {
72                 cFYI(1, ("Null xattr names not supported"));
73         } else if (strncmp(ea_name, CIFS_XATTR_USER_PREFIX, 5)
74                 && (strncmp(ea_name, CIFS_XATTR_OS2_PREFIX, 4))) {
75                 cFYI(1,
76                     ("illegal xattr request %s (only user namespace supported)",
77                         ea_name));
78                 /* BB what if no namespace prefix? */
79                 /* Should we just pass them to server, except for
80                 system and perhaps security prefixes? */
81         } else {
82                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
83                         goto remove_ea_exit;
84
85                 ea_name += 5; /* skip past user. prefix */
86                 rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, NULL,
87                         (__u16)0, cifs_sb->local_nls,
88                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
89         }
90 remove_ea_exit:
91         kfree(full_path);
92         FreeXid(xid);
93 #endif
94         return rc;
95 }
96
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 cifsTconInfo *pTcon;
105         struct super_block *sb;
106         char *full_path;
107
108         if (direntry == NULL)
109                 return -EIO;
110         if (direntry->d_inode == NULL)
111                 return -EIO;
112         sb = direntry->d_inode->i_sb;
113         if (sb == NULL)
114                 return -EIO;
115         xid = GetXid();
116
117         cifs_sb = CIFS_SB(sb);
118         pTcon = cifs_sb->tcon;
119
120         full_path = build_path_from_dentry(direntry);
121         if (full_path == NULL) {
122                 rc = -ENOMEM;
123                 FreeXid(xid);
124                 return rc;
125         }
126         /* return dos attributes as pseudo xattr */
127         /* return alt name if available as pseudo attr */
128
129         /* if proc/fs/cifs/streamstoxattr is set then
130                 search server for EAs or streams to
131                 returns as xattrs */
132         if (value_size > MAX_EA_VALUE_SIZE) {
133                 cFYI(1, ("size of EA value too large"));
134                 kfree(full_path);
135                 FreeXid(xid);
136                 return -EOPNOTSUPP;
137         }
138
139         if (ea_name == NULL) {
140                 cFYI(1, ("Null xattr names not supported"));
141         } else if (strncmp(ea_name, CIFS_XATTR_USER_PREFIX, 5) == 0) {
142                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
143                         goto set_ea_exit;
144                 if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0)
145                         cFYI(1, ("attempt to set cifs inode metadata"));
146
147                 ea_name += 5; /* skip past user. prefix */
148                 rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
149                         (__u16)value_size, cifs_sb->local_nls,
150                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
151         } else if (strncmp(ea_name, CIFS_XATTR_OS2_PREFIX, 4) == 0) {
152                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
153                         goto set_ea_exit;
154
155                 ea_name += 4; /* skip past os2. prefix */
156                 rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
157                         (__u16)value_size, cifs_sb->local_nls,
158                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
159         } else {
160                 int temp;
161                 temp = strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
162                         strlen(POSIX_ACL_XATTR_ACCESS));
163                 if (temp == 0) {
164 #ifdef CONFIG_CIFS_POSIX
165                         if (sb->s_flags & MS_POSIXACL)
166                                 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
167                                         ea_value, (const int)value_size,
168                                         ACL_TYPE_ACCESS, cifs_sb->local_nls,
169                                         cifs_sb->mnt_cifs_flags &
170                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
171                         cFYI(1, ("set POSIX ACL rc %d", rc));
172 #else
173                         cFYI(1, ("set POSIX ACL not supported"));
174 #endif
175                 } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
176                                    strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
177 #ifdef CONFIG_CIFS_POSIX
178                         if (sb->s_flags & MS_POSIXACL)
179                                 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
180                                         ea_value, (const int)value_size,
181                                         ACL_TYPE_DEFAULT, cifs_sb->local_nls,
182                                         cifs_sb->mnt_cifs_flags &
183                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
184                         cFYI(1, ("set POSIX default ACL rc %d", rc));
185 #else
186                         cFYI(1, ("set default POSIX ACL not supported"));
187 #endif
188                 } else {
189                         cFYI(1, ("illegal xattr request %s (only user namespace"
190                                  " supported)", ea_name));
191                   /* BB what if no namespace prefix? */
192                   /* Should we just pass them to server, except for
193                   system and perhaps security prefixes? */
194                 }
195         }
196
197 set_ea_exit:
198         kfree(full_path);
199         FreeXid(xid);
200 #endif
201         return rc;
202 }
203
204 ssize_t cifs_getxattr(struct dentry *direntry, const char *ea_name,
205         void *ea_value, size_t buf_size)
206 {
207         ssize_t rc = -EOPNOTSUPP;
208 #ifdef CONFIG_CIFS_XATTR
209         int xid;
210         struct cifs_sb_info *cifs_sb;
211         struct cifsTconInfo *pTcon;
212         struct super_block *sb;
213         char *full_path;
214
215         if (direntry == NULL)
216                 return -EIO;
217         if (direntry->d_inode == NULL)
218                 return -EIO;
219         sb = direntry->d_inode->i_sb;
220         if (sb == NULL)
221                 return -EIO;
222
223         xid = GetXid();
224
225         cifs_sb = CIFS_SB(sb);
226         pTcon = cifs_sb->tcon;
227
228         full_path = build_path_from_dentry(direntry);
229         if (full_path == NULL) {
230                 rc = -ENOMEM;
231                 FreeXid(xid);
232                 return rc;
233         }
234         /* return dos attributes as pseudo xattr */
235         /* return alt name if available as pseudo attr */
236         if (ea_name == NULL) {
237                 cFYI(1, ("Null xattr names not supported"));
238         } else if (strncmp(ea_name, CIFS_XATTR_USER_PREFIX, 5) == 0) {
239                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
240                         goto get_ea_exit;
241
242                 if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0) {
243                         cFYI(1, ("attempt to query cifs inode metadata"));
244                         /* revalidate/getattr then populate from inode */
245                 } /* BB add else when above is implemented */
246                 ea_name += 5; /* skip past user. prefix */
247                 rc = CIFSSMBQueryEA(xid, pTcon, full_path, ea_name, ea_value,
248                         buf_size, cifs_sb->local_nls,
249                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
250         } else if (strncmp(ea_name, CIFS_XATTR_OS2_PREFIX, 4) == 0) {
251                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
252                         goto get_ea_exit;
253
254                 ea_name += 4; /* skip past os2. prefix */
255                 rc = CIFSSMBQueryEA(xid, pTcon, full_path, ea_name, ea_value,
256                         buf_size, cifs_sb->local_nls,
257                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
258         } else if (strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
259                           strlen(POSIX_ACL_XATTR_ACCESS)) == 0) {
260 #ifdef CONFIG_CIFS_POSIX
261                 if (sb->s_flags & MS_POSIXACL)
262                         rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
263                                 ea_value, buf_size, ACL_TYPE_ACCESS,
264                                 cifs_sb->local_nls,
265                                 cifs_sb->mnt_cifs_flags &
266                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
267 #ifdef CONFIG_CIFS_EXPERIMENTAL
268                 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) {
269                         __u16 fid;
270                         int oplock = 0;
271                         struct cifs_ntsd *pacl = NULL;
272                         __u32 buflen = 0;
273                         if (experimEnabled)
274                                 rc = CIFSSMBOpen(xid, pTcon, full_path,
275                                         FILE_OPEN, GENERIC_READ, 0, &fid,
276                                         &oplock, NULL, cifs_sb->local_nls,
277                                         cifs_sb->mnt_cifs_flags &
278                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
279                         /* else rc is EOPNOTSUPP from above */
280
281                         if (rc == 0) {
282                                 rc = CIFSSMBGetCIFSACL(xid, pTcon, fid, &pacl,
283                                                       &buflen);
284                                 CIFSSMBClose(xid, pTcon, fid);
285                         }
286                 }
287 #endif /* EXPERIMENTAL */
288 #else
289                 cFYI(1, ("query POSIX ACL not supported yet"));
290 #endif /* CONFIG_CIFS_POSIX */
291         } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
292                           strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
293 #ifdef CONFIG_CIFS_POSIX
294                 if (sb->s_flags & MS_POSIXACL)
295                         rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
296                                 ea_value, buf_size, ACL_TYPE_DEFAULT,
297                                 cifs_sb->local_nls,
298                                 cifs_sb->mnt_cifs_flags &
299                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
300 #else
301                 cFYI(1, ("query POSIX default ACL not supported yet"));
302 #endif
303         } else if (strncmp(ea_name,
304                   CIFS_XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) {
305                 cFYI(1, ("Trusted xattr namespace not supported yet"));
306         } else if (strncmp(ea_name,
307                   CIFS_XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) == 0) {
308                 cFYI(1, ("Security xattr namespace not supported yet"));
309         } else
310                 cFYI(1,
311                     ("illegal xattr request %s (only user namespace supported)",
312                         ea_name));
313
314         /* We could add an additional check for streams ie
315             if proc/fs/cifs/streamstoxattr is set then
316                 search server for EAs or streams to
317                 returns as xattrs */
318
319         if (rc == -EINVAL)
320                 rc = -EOPNOTSUPP;
321
322 get_ea_exit:
323         kfree(full_path);
324         FreeXid(xid);
325 #endif
326         return rc;
327 }
328
329 ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
330 {
331         ssize_t rc = -EOPNOTSUPP;
332 #ifdef CONFIG_CIFS_XATTR
333         int xid;
334         struct cifs_sb_info *cifs_sb;
335         struct cifsTconInfo *pTcon;
336         struct super_block *sb;
337         char *full_path;
338
339         if (direntry == NULL)
340                 return -EIO;
341         if (direntry->d_inode == NULL)
342                 return -EIO;
343         sb = direntry->d_inode->i_sb;
344         if (sb == NULL)
345                 return -EIO;
346
347         cifs_sb = CIFS_SB(sb);
348         pTcon = cifs_sb->tcon;
349
350         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
351                 return -EOPNOTSUPP;
352
353         xid = GetXid();
354
355         full_path = build_path_from_dentry(direntry);
356         if (full_path == NULL) {
357                 rc = -ENOMEM;
358                 FreeXid(xid);
359                 return rc;
360         }
361         /* return dos attributes as pseudo xattr */
362         /* return alt name if available as pseudo attr */
363
364         /* if proc/fs/cifs/streamstoxattr is set then
365                 search server for EAs or streams to
366                 returns as xattrs */
367         rc = CIFSSMBQAllEAs(xid, pTcon, full_path, data, buf_size,
368                                 cifs_sb->local_nls,
369                                 cifs_sb->mnt_cifs_flags &
370                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
371
372         kfree(full_path);
373         FreeXid(xid);
374 #endif
375         return rc;
376 }