4 * Copyright (C) International Business Machines Corp., 2002,2008
5 * Author(s): Steve French (sfrench@us.ibm.com)
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.
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.
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
22 #include <linux/stat.h>
23 #include <linux/slab.h>
24 #include <linux/namei.h>
28 #include "cifsproto.h"
29 #include "cifs_debug.h"
30 #include "cifs_fs_sb.h"
33 #define CIFS_MF_SYMLINK_LEN_OFFSET (4+1)
34 #define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1))
35 #define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1))
36 #define CIFS_MF_SYMLINK_LINK_MAXLEN (1024)
37 #define CIFS_MF_SYMLINK_FILE_SIZE \
38 (CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN)
40 #define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n"
41 #define CIFS_MF_SYMLINK_MD5_FORMAT \
42 "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n"
43 #define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) \
44 md5_hash[0], md5_hash[1], md5_hash[2], md5_hash[3], \
45 md5_hash[4], md5_hash[5], md5_hash[6], md5_hash[7], \
46 md5_hash[8], md5_hash[9], md5_hash[10], md5_hash[11],\
47 md5_hash[12], md5_hash[13], md5_hash[14], md5_hash[15]
50 CIFSParseMFSymlink(const u8
*buf
,
52 unsigned int *_link_len
,
56 unsigned int link_len
;
59 struct MD5Context md5_ctx
;
63 if (buf_len
!= CIFS_MF_SYMLINK_FILE_SIZE
)
66 md5_str1
= (const char *)&buf
[CIFS_MF_SYMLINK_MD5_OFFSET
];
67 link_str
= (const char *)&buf
[CIFS_MF_SYMLINK_LINK_OFFSET
];
69 rc
= sscanf(buf
, CIFS_MF_SYMLINK_LEN_FORMAT
, &link_len
);
73 cifs_MD5_init(&md5_ctx
);
74 cifs_MD5_update(&md5_ctx
, (const u8
*)link_str
, link_len
);
75 cifs_MD5_final(md5_hash
, &md5_ctx
);
77 snprintf(md5_str2
, sizeof(md5_str2
),
78 CIFS_MF_SYMLINK_MD5_FORMAT
,
79 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash
));
81 if (strncmp(md5_str1
, md5_str2
, 17) != 0)
85 *_link_str
= kstrndup(link_str
, link_len
, GFP_KERNEL
);
90 *_link_len
= link_len
;
95 CIFSFormatMFSymlink(u8
*buf
, unsigned int buf_len
, const char *link_str
)
97 unsigned int link_len
;
99 struct MD5Context md5_ctx
;
102 if (buf_len
!= CIFS_MF_SYMLINK_FILE_SIZE
)
105 link_len
= strlen(link_str
);
107 if (link_len
> CIFS_MF_SYMLINK_LINK_MAXLEN
)
108 return -ENAMETOOLONG
;
110 cifs_MD5_init(&md5_ctx
);
111 cifs_MD5_update(&md5_ctx
, (const u8
*)link_str
, link_len
);
112 cifs_MD5_final(md5_hash
, &md5_ctx
);
114 snprintf(buf
, buf_len
,
115 CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT
,
117 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash
));
119 ofs
= CIFS_MF_SYMLINK_LINK_OFFSET
;
120 memcpy(buf
+ ofs
, link_str
, link_len
);
123 if (ofs
< CIFS_MF_SYMLINK_FILE_SIZE
) {
128 while (ofs
< CIFS_MF_SYMLINK_FILE_SIZE
) {
137 CIFSCreateMFSymLink(const int xid
, struct cifsTconInfo
*tcon
,
138 const char *fromName
, const char *toName
,
139 const struct nls_table
*nls_codepage
, int remap
)
145 unsigned int bytes_written
= 0;
147 buf
= kmalloc(CIFS_MF_SYMLINK_FILE_SIZE
, GFP_KERNEL
);
151 rc
= CIFSFormatMFSymlink(buf
, CIFS_MF_SYMLINK_FILE_SIZE
, toName
);
157 rc
= CIFSSMBOpen(xid
, tcon
, fromName
, FILE_CREATE
, GENERIC_WRITE
,
158 CREATE_NOT_DIR
, &netfid
, &oplock
, NULL
,
159 nls_codepage
, remap
);
165 rc
= CIFSSMBWrite(xid
, tcon
, netfid
,
166 CIFS_MF_SYMLINK_FILE_SIZE
/* length */,
168 &bytes_written
, buf
, NULL
, 0);
169 CIFSSMBClose(xid
, tcon
, netfid
);
174 if (bytes_written
!= CIFS_MF_SYMLINK_FILE_SIZE
)
181 CIFSQueryMFSymLink(const int xid
, struct cifsTconInfo
*tcon
,
182 const unsigned char *searchName
, char **symlinkinfo
,
183 const struct nls_table
*nls_codepage
, int remap
)
190 unsigned int bytes_read
= 0;
191 int buf_type
= CIFS_NO_BUFFER
;
192 unsigned int link_len
= 0;
193 FILE_ALL_INFO file_info
;
195 rc
= CIFSSMBOpen(xid
, tcon
, searchName
, FILE_OPEN
, GENERIC_READ
,
196 CREATE_NOT_DIR
, &netfid
, &oplock
, &file_info
,
197 nls_codepage
, remap
);
201 if (file_info
.EndOfFile
!= CIFS_MF_SYMLINK_FILE_SIZE
) {
202 CIFSSMBClose(xid
, tcon
, netfid
);
203 /* it's not a symlink */
207 buf
= kmalloc(CIFS_MF_SYMLINK_FILE_SIZE
, GFP_KERNEL
);
212 rc
= CIFSSMBRead(xid
, tcon
, netfid
,
213 CIFS_MF_SYMLINK_FILE_SIZE
/* length */,
215 &bytes_read
, &pbuf
, &buf_type
);
216 CIFSSMBClose(xid
, tcon
, netfid
);
222 rc
= CIFSParseMFSymlink(buf
, bytes_read
, &link_len
, symlinkinfo
);
231 CIFSCouldBeMFSymlink(const struct cifs_fattr
*fattr
)
233 if (!(fattr
->cf_mode
& S_IFREG
))
234 /* it's not a symlink */
237 if (fattr
->cf_eof
!= CIFS_MF_SYMLINK_FILE_SIZE
)
238 /* it's not a symlink */
245 CIFSCheckMFSymlink(struct cifs_fattr
*fattr
,
246 const unsigned char *path
,
247 struct cifs_sb_info
*cifs_sb
, int xid
)
252 struct cifsTconInfo
*pTcon
= cifs_sb
->tcon
;
255 unsigned int bytes_read
= 0;
256 int buf_type
= CIFS_NO_BUFFER
;
257 unsigned int link_len
= 0;
258 FILE_ALL_INFO file_info
;
260 if (!CIFSCouldBeMFSymlink(fattr
))
261 /* it's not a symlink */
264 rc
= CIFSSMBOpen(xid
, pTcon
, path
, FILE_OPEN
, GENERIC_READ
,
265 CREATE_NOT_DIR
, &netfid
, &oplock
, &file_info
,
267 cifs_sb
->mnt_cifs_flags
&
268 CIFS_MOUNT_MAP_SPECIAL_CHR
);
272 if (file_info
.EndOfFile
!= CIFS_MF_SYMLINK_FILE_SIZE
) {
273 CIFSSMBClose(xid
, pTcon
, netfid
);
274 /* it's not a symlink */
278 buf
= kmalloc(CIFS_MF_SYMLINK_FILE_SIZE
, GFP_KERNEL
);
283 rc
= CIFSSMBRead(xid
, pTcon
, netfid
,
284 CIFS_MF_SYMLINK_FILE_SIZE
/* length */,
286 &bytes_read
, &pbuf
, &buf_type
);
287 CIFSSMBClose(xid
, pTcon
, netfid
);
293 rc
= CIFSParseMFSymlink(buf
, bytes_read
, &link_len
, NULL
);
296 /* it's not a symlink */
301 /* it is a symlink */
302 fattr
->cf_eof
= link_len
;
303 fattr
->cf_mode
&= ~S_IFMT
;
304 fattr
->cf_mode
|= S_IFLNK
| S_IRWXU
| S_IRWXG
| S_IRWXO
;
305 fattr
->cf_dtype
= DT_LNK
;
310 cifs_hardlink(struct dentry
*old_file
, struct inode
*inode
,
311 struct dentry
*direntry
)
315 char *fromName
= NULL
;
317 struct cifs_sb_info
*cifs_sb_target
;
318 struct cifsTconInfo
*pTcon
;
319 struct cifsInodeInfo
*cifsInode
;
323 cifs_sb_target
= CIFS_SB(inode
->i_sb
);
324 pTcon
= cifs_sb_target
->tcon
;
326 /* No need to check for cross device links since server will do that
327 BB note DFS case in future though (when we may have to check) */
329 fromName
= build_path_from_dentry(old_file
);
330 toName
= build_path_from_dentry(direntry
);
331 if ((fromName
== NULL
) || (toName
== NULL
)) {
336 /* if (cifs_sb_target->tcon->ses->capabilities & CAP_UNIX)*/
338 rc
= CIFSUnixCreateHardLink(xid
, pTcon
, fromName
, toName
,
339 cifs_sb_target
->local_nls
,
340 cifs_sb_target
->mnt_cifs_flags
&
341 CIFS_MOUNT_MAP_SPECIAL_CHR
);
343 rc
= CIFSCreateHardLink(xid
, pTcon
, fromName
, toName
,
344 cifs_sb_target
->local_nls
,
345 cifs_sb_target
->mnt_cifs_flags
&
346 CIFS_MOUNT_MAP_SPECIAL_CHR
);
347 if ((rc
== -EIO
) || (rc
== -EINVAL
))
351 d_drop(direntry
); /* force new lookup from server of target */
353 /* if source file is cached (oplocked) revalidate will not go to server
354 until the file is closed or oplock broken so update nlinks locally */
355 if (old_file
->d_inode
) {
356 cifsInode
= CIFS_I(old_file
->d_inode
);
358 old_file
->d_inode
->i_nlink
++;
359 /* BB should we make this contingent on superblock flag NOATIME? */
360 /* old_file->d_inode->i_ctime = CURRENT_TIME;*/
361 /* parent dir timestamps will update from srv
362 within a second, would it really be worth it
363 to set the parent dir cifs inode time to zero
364 to force revalidate (faster) for it too? */
366 /* if not oplocked will force revalidate to get info
367 on source file from srv */
370 /* Will update parent dir timestamps from srv within a second.
371 Would it really be worth it to set the parent dir (cifs
372 inode) time field to zero to force revalidate on parent
374 CIFS_I(inode)->time = 0; */
385 cifs_follow_link(struct dentry
*direntry
, struct nameidata
*nd
)
387 struct inode
*inode
= direntry
->d_inode
;
390 char *full_path
= NULL
;
391 char *target_path
= NULL
;
392 struct cifs_sb_info
*cifs_sb
= CIFS_SB(inode
->i_sb
);
393 struct cifsTconInfo
*tcon
= cifs_sb
->tcon
;
398 * For now, we just handle symlinks with unix extensions enabled.
399 * Eventually we should handle NTFS reparse points, and MacOS
400 * symlink support. For instance...
402 * rc = CIFSSMBQueryReparseLinkInfo(...)
404 * For now, just return -EACCES when the server doesn't support posix
405 * extensions. Note that we still allow querying symlinks when posix
406 * extensions are manually disabled. We could disable these as well
407 * but there doesn't seem to be any harm in allowing the client to
410 if (!(tcon
->ses
->capabilities
& CAP_UNIX
)) {
415 full_path
= build_path_from_dentry(direntry
);
419 cFYI(1, "Full path: %s inode = 0x%p", full_path
, inode
);
421 rc
= CIFSSMBUnixQuerySymLink(xid
, tcon
, full_path
, &target_path
,
427 target_path
= ERR_PTR(rc
);
431 nd_set_link(nd
, target_path
);
436 cifs_symlink(struct inode
*inode
, struct dentry
*direntry
, const char *symname
)
438 int rc
= -EOPNOTSUPP
;
440 struct cifs_sb_info
*cifs_sb
;
441 struct cifsTconInfo
*pTcon
;
442 char *full_path
= NULL
;
443 struct inode
*newinode
= NULL
;
447 cifs_sb
= CIFS_SB(inode
->i_sb
);
448 pTcon
= cifs_sb
->tcon
;
450 full_path
= build_path_from_dentry(direntry
);
452 if (full_path
== NULL
) {
458 cFYI(1, "Full path: %s", full_path
);
459 cFYI(1, "symname is %s", symname
);
461 /* BB what if DFS and this volume is on different share? BB */
463 rc
= CIFSUnixCreateSymLink(xid
, pTcon
, full_path
, symname
,
466 rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
467 cifs_sb_target->local_nls); */
471 rc
= cifs_get_inode_info_unix(&newinode
, full_path
,
474 rc
= cifs_get_inode_info(&newinode
, full_path
, NULL
,
475 inode
->i_sb
, xid
, NULL
);
478 cFYI(1, "Create symlink ok, getinodeinfo fail rc = %d",
482 direntry
->d_op
= &cifs_ci_dentry_ops
;
484 direntry
->d_op
= &cifs_dentry_ops
;
485 d_instantiate(direntry
, newinode
);
494 void cifs_put_link(struct dentry
*direntry
, struct nameidata
*nd
, void *cookie
)
496 char *p
= nd_get_link(nd
);