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 "cifsfs.h"
26#include "cifspdu.h"
27#include "cifsglob.h"
28#include "cifsproto.h"
29#include "cifs_debug.h"
30
31#define MAX_EA_VALUE_SIZE 65535
32#define CIFS_XATTR_DOS_ATTRIB "user.DosAttrib"
33#define CIFS_XATTR_USER_PREFIX "user."
34#define CIFS_XATTR_SYSTEM_PREFIX "system."
35#define CIFS_XATTR_OS2_PREFIX "os2."
36#define CIFS_XATTR_SECURITY_PREFIX ".security"
37#define CIFS_XATTR_TRUSTED_PREFIX "trusted."
38#define XATTR_TRUSTED_PREFIX_LEN  8
39#define XATTR_SECURITY_PREFIX_LEN 9
40/* BB need to add server (Samba e.g) support for security and trusted prefix */
41
42
43
44int cifs_removexattr(struct dentry *direntry, const char *ea_name)
45{
46	int rc = -EOPNOTSUPP;
47#ifdef CONFIG_CIFS_XATTR
48	int xid;
49	struct cifs_sb_info *cifs_sb;
50	struct cifsTconInfo *pTcon;
51	struct super_block *sb;
52	char *full_path;
53
54	if (direntry == NULL)
55		return -EIO;
56	if (direntry->d_inode == NULL)
57		return -EIO;
58	sb = direntry->d_inode->i_sb;
59	if (sb == NULL)
60		return -EIO;
61	xid = GetXid();
62
63	cifs_sb = CIFS_SB(sb);
64	pTcon = cifs_sb->tcon;
65
66	full_path = build_path_from_dentry(direntry);
67	if (full_path == NULL) {
68		rc = -ENOMEM;
69		FreeXid(xid);
70		return rc;
71	}
72	if (ea_name == NULL) {
73		cFYI(1, "Null xattr names not supported");
74	} else if (strncmp(ea_name, CIFS_XATTR_USER_PREFIX, 5)
75		&& (strncmp(ea_name, CIFS_XATTR_OS2_PREFIX, 4))) {
76		cFYI(1,
77		     "illegal xattr request %s (only user namespace supported)",
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 += 5; /* skip past user. prefix */
87		rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, NULL,
88			(__u16)0, cifs_sb->local_nls,
89			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
90	}
91remove_ea_exit:
92	kfree(full_path);
93	FreeXid(xid);
94#endif
95	return rc;
96}
97
98int cifs_setxattr(struct dentry *direntry, const char *ea_name,
99		  const void *ea_value, size_t value_size, int flags)
100{
101	int rc = -EOPNOTSUPP;
102#ifdef CONFIG_CIFS_XATTR
103	int xid;
104	struct cifs_sb_info *cifs_sb;
105	struct cifsTconInfo *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	xid = GetXid();
117
118	cifs_sb = CIFS_SB(sb);
119	pTcon = cifs_sb->tcon;
120
121	full_path = build_path_from_dentry(direntry);
122	if (full_path == NULL) {
123		rc = -ENOMEM;
124		FreeXid(xid);
125		return rc;
126	}
127	/* return dos attributes as pseudo xattr */
128	/* return alt name if available as pseudo attr */
129
130	/* if proc/fs/cifs/streamstoxattr is set then
131		search server for EAs or streams to
132		returns as xattrs */
133	if (value_size > MAX_EA_VALUE_SIZE) {
134		cFYI(1, "size of EA value too large");
135		kfree(full_path);
136		FreeXid(xid);
137		return -EOPNOTSUPP;
138	}
139
140	if (ea_name == NULL) {
141		cFYI(1, "Null xattr names not supported");
142	} else if (strncmp(ea_name, CIFS_XATTR_USER_PREFIX, 5) == 0) {
143		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
144			goto set_ea_exit;
145		if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0)
146			cFYI(1, "attempt to set cifs inode metadata");
147
148		ea_name += 5; /* skip past user. prefix */
149		rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
150			(__u16)value_size, cifs_sb->local_nls,
151			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
152	} else if (strncmp(ea_name, CIFS_XATTR_OS2_PREFIX, 4) == 0) {
153		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
154			goto set_ea_exit;
155
156		ea_name += 4; /* skip past os2. prefix */
157		rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
158			(__u16)value_size, cifs_sb->local_nls,
159			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
160	} else {
161		int temp;
162		temp = strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
163			strlen(POSIX_ACL_XATTR_ACCESS));
164		if (temp == 0) {
165#ifdef CONFIG_CIFS_POSIX
166			if (sb->s_flags & MS_POSIXACL)
167				rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
168					ea_value, (const int)value_size,
169					ACL_TYPE_ACCESS, cifs_sb->local_nls,
170					cifs_sb->mnt_cifs_flags &
171						CIFS_MOUNT_MAP_SPECIAL_CHR);
172			cFYI(1, "set POSIX ACL rc %d", rc);
173#else
174			cFYI(1, "set POSIX ACL not supported");
175#endif
176		} else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
177				   strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
178#ifdef CONFIG_CIFS_POSIX
179			if (sb->s_flags & MS_POSIXACL)
180				rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
181					ea_value, (const int)value_size,
182					ACL_TYPE_DEFAULT, cifs_sb->local_nls,
183					cifs_sb->mnt_cifs_flags &
184						CIFS_MOUNT_MAP_SPECIAL_CHR);
185			cFYI(1, "set POSIX default ACL rc %d", rc);
186#else
187			cFYI(1, "set default POSIX ACL not supported");
188#endif
189		} else {
190			cFYI(1, "illegal xattr request %s (only user namespace"
191				" supported)", ea_name);
192		  /* BB what if no namespace prefix? */
193		  /* Should we just pass them to server, except for
194		  system and perhaps security prefixes? */
195		}
196	}
197
198set_ea_exit:
199	kfree(full_path);
200	FreeXid(xid);
201#endif
202	return rc;
203}
204
205ssize_t cifs_getxattr(struct dentry *direntry, const char *ea_name,
206	void *ea_value, size_t buf_size)
207{
208	ssize_t rc = -EOPNOTSUPP;
209#ifdef CONFIG_CIFS_XATTR
210	int xid;
211	struct cifs_sb_info *cifs_sb;
212	struct cifsTconInfo *pTcon;
213	struct super_block *sb;
214	char *full_path;
215
216	if (direntry == NULL)
217		return -EIO;
218	if (direntry->d_inode == NULL)
219		return -EIO;
220	sb = direntry->d_inode->i_sb;
221	if (sb == NULL)
222		return -EIO;
223
224	xid = GetXid();
225
226	cifs_sb = CIFS_SB(sb);
227	pTcon = cifs_sb->tcon;
228
229	full_path = build_path_from_dentry(direntry);
230	if (full_path == NULL) {
231		rc = -ENOMEM;
232		FreeXid(xid);
233		return rc;
234	}
235	/* return dos attributes as pseudo xattr */
236	/* return alt name if available as pseudo attr */
237	if (ea_name == NULL) {
238		cFYI(1, "Null xattr names not supported");
239	} else if (strncmp(ea_name, CIFS_XATTR_USER_PREFIX, 5) == 0) {
240		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
241			goto get_ea_exit;
242
243		if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0) {
244			cFYI(1, "attempt to query cifs inode metadata");
245			/* revalidate/getattr then populate from inode */
246		} /* BB add else when above is implemented */
247		ea_name += 5; /* skip past user. prefix */
248		rc = CIFSSMBQAllEAs(xid, pTcon, full_path, ea_name, ea_value,
249			buf_size, cifs_sb->local_nls,
250			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
251	} else if (strncmp(ea_name, CIFS_XATTR_OS2_PREFIX, 4) == 0) {
252		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
253			goto get_ea_exit;
254
255		ea_name += 4; /* skip past os2. prefix */
256		rc = CIFSSMBQAllEAs(xid, pTcon, full_path, ea_name, ea_value,
257			buf_size, cifs_sb->local_nls,
258			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
259	} else if (strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
260			  strlen(POSIX_ACL_XATTR_ACCESS)) == 0) {
261#ifdef CONFIG_CIFS_POSIX
262		if (sb->s_flags & MS_POSIXACL)
263			rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
264				ea_value, buf_size, ACL_TYPE_ACCESS,
265				cifs_sb->local_nls,
266				cifs_sb->mnt_cifs_flags &
267					CIFS_MOUNT_MAP_SPECIAL_CHR);
268#ifdef CONFIG_CIFS_EXPERIMENTAL
269		else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) {
270			__u16 fid;
271			int oplock = 0;
272			struct cifs_ntsd *pacl = NULL;
273			__u32 buflen = 0;
274			if (experimEnabled)
275				rc = CIFSSMBOpen(xid, pTcon, full_path,
276					FILE_OPEN, GENERIC_READ, 0, &fid,
277					&oplock, NULL, cifs_sb->local_nls,
278					cifs_sb->mnt_cifs_flags &
279					CIFS_MOUNT_MAP_SPECIAL_CHR);
280			/* else rc is EOPNOTSUPP from above */
281
282			if (rc == 0) {
283				rc = CIFSSMBGetCIFSACL(xid, pTcon, fid, &pacl,
284						      &buflen);
285				CIFSSMBClose(xid, pTcon, fid);
286			}
287		}
288#endif /* EXPERIMENTAL */
289#else
290		cFYI(1, "query POSIX ACL not supported yet");
291#endif /* CONFIG_CIFS_POSIX */
292	} else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
293			  strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
294#ifdef CONFIG_CIFS_POSIX
295		if (sb->s_flags & MS_POSIXACL)
296			rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
297				ea_value, buf_size, ACL_TYPE_DEFAULT,
298				cifs_sb->local_nls,
299				cifs_sb->mnt_cifs_flags &
300					CIFS_MOUNT_MAP_SPECIAL_CHR);
301#else
302		cFYI(1, "query POSIX default ACL not supported yet");
303#endif
304	} else if (strncmp(ea_name,
305		  CIFS_XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) {
306		cFYI(1, "Trusted xattr namespace not supported yet");
307	} else if (strncmp(ea_name,
308		  CIFS_XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) == 0) {
309		cFYI(1, "Security xattr namespace not supported yet");
310	} else
311		cFYI(1,
312		    "illegal xattr request %s (only user namespace supported)",
313		     ea_name);
314
315	/* We could add an additional check for streams ie
316	    if proc/fs/cifs/streamstoxattr is set then
317		search server for EAs or streams to
318		returns as xattrs */
319
320	if (rc == -EINVAL)
321		rc = -EOPNOTSUPP;
322
323get_ea_exit:
324	kfree(full_path);
325	FreeXid(xid);
326#endif
327	return rc;
328}
329
330ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
331{
332	ssize_t rc = -EOPNOTSUPP;
333#ifdef CONFIG_CIFS_XATTR
334	int xid;
335	struct cifs_sb_info *cifs_sb;
336	struct cifsTconInfo *pTcon;
337	struct super_block *sb;
338	char *full_path;
339
340	if (direntry == NULL)
341		return -EIO;
342	if (direntry->d_inode == NULL)
343		return -EIO;
344	sb = direntry->d_inode->i_sb;
345	if (sb == NULL)
346		return -EIO;
347
348	cifs_sb = CIFS_SB(sb);
349	pTcon = cifs_sb->tcon;
350
351	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
352		return -EOPNOTSUPP;
353
354	xid = GetXid();
355
356	full_path = build_path_from_dentry(direntry);
357	if (full_path == NULL) {
358		rc = -ENOMEM;
359		FreeXid(xid);
360		return rc;
361	}
362	/* return dos attributes as pseudo xattr */
363	/* return alt name if available as pseudo attr */
364
365	/* if proc/fs/cifs/streamstoxattr is set then
366		search server for EAs or streams to
367		returns as xattrs */
368	rc = CIFSSMBQAllEAs(xid, pTcon, full_path, NULL, data,
369				buf_size, cifs_sb->local_nls,
370				cifs_sb->mnt_cifs_flags &
371					CIFS_MOUNT_MAP_SPECIAL_CHR);
372
373	kfree(full_path);
374	FreeXid(xid);
375#endif
376	return rc;
377}
378