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 * M-F Symlink Functions - Begin
36 #define CIFS_MF_SYMLINK_LEN_OFFSET (4+1)
37 #define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1))
38 #define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1))
39 #define CIFS_MF_SYMLINK_LINK_MAXLEN (1024)
40 #define CIFS_MF_SYMLINK_FILE_SIZE \
41 (CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN)
43 #define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n"
44 #define CIFS_MF_SYMLINK_MD5_FORMAT \
45 "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n"
46 #define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) \
47 md5_hash[0], md5_hash[1], md5_hash[2], md5_hash[3], \
48 md5_hash[4], md5_hash[5], md5_hash[6], md5_hash[7], \
49 md5_hash[8], md5_hash[9], md5_hash[10], md5_hash[11],\
50 md5_hash[12], md5_hash[13], md5_hash[14], md5_hash[15]
53 symlink_hash(unsigned int link_len
, const char *link_str
, u8
*md5_hash
)
57 struct crypto_shash
*md5
;
58 struct sdesc
*sdescmd5
;
60 md5
= crypto_alloc_shash("md5", 0, 0);
63 cifs_dbg(VFS
, "%s: Crypto md5 allocation error %d\n",
67 size
= sizeof(struct shash_desc
) + crypto_shash_descsize(md5
);
68 sdescmd5
= kmalloc(size
, GFP_KERNEL
);
71 goto symlink_hash_err
;
73 sdescmd5
->shash
.tfm
= md5
;
74 sdescmd5
->shash
.flags
= 0x0;
76 rc
= crypto_shash_init(&sdescmd5
->shash
);
78 cifs_dbg(VFS
, "%s: Could not init md5 shash\n", __func__
);
79 goto symlink_hash_err
;
81 rc
= crypto_shash_update(&sdescmd5
->shash
, link_str
, link_len
);
83 cifs_dbg(VFS
, "%s: Could not update with link_str\n", __func__
);
84 goto symlink_hash_err
;
86 rc
= crypto_shash_final(&sdescmd5
->shash
, md5_hash
);
88 cifs_dbg(VFS
, "%s: Could not generate md5 hash\n", __func__
);
91 crypto_free_shash(md5
);
98 parse_mf_symlink(const u8
*buf
, unsigned int buf_len
, unsigned int *_link_len
,
102 unsigned int link_len
;
103 const char *md5_str1
;
104 const char *link_str
;
108 if (buf_len
!= CIFS_MF_SYMLINK_FILE_SIZE
)
111 md5_str1
= (const char *)&buf
[CIFS_MF_SYMLINK_MD5_OFFSET
];
112 link_str
= (const char *)&buf
[CIFS_MF_SYMLINK_LINK_OFFSET
];
114 rc
= sscanf(buf
, CIFS_MF_SYMLINK_LEN_FORMAT
, &link_len
);
118 rc
= symlink_hash(link_len
, link_str
, md5_hash
);
120 cifs_dbg(FYI
, "%s: MD5 hash failure: %d\n", __func__
, rc
);
124 snprintf(md5_str2
, sizeof(md5_str2
),
125 CIFS_MF_SYMLINK_MD5_FORMAT
,
126 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash
));
128 if (strncmp(md5_str1
, md5_str2
, 17) != 0)
132 *_link_str
= kstrndup(link_str
, link_len
, GFP_KERNEL
);
137 *_link_len
= link_len
;
142 format_mf_symlink(u8
*buf
, unsigned int buf_len
, const char *link_str
)
145 unsigned int link_len
;
149 if (buf_len
!= CIFS_MF_SYMLINK_FILE_SIZE
)
152 link_len
= strlen(link_str
);
154 if (link_len
> CIFS_MF_SYMLINK_LINK_MAXLEN
)
155 return -ENAMETOOLONG
;
157 rc
= symlink_hash(link_len
, link_str
, md5_hash
);
159 cifs_dbg(FYI
, "%s: MD5 hash failure: %d\n", __func__
, rc
);
163 snprintf(buf
, buf_len
,
164 CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT
,
166 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash
));
168 ofs
= CIFS_MF_SYMLINK_LINK_OFFSET
;
169 memcpy(buf
+ ofs
, link_str
, link_len
);
172 if (ofs
< CIFS_MF_SYMLINK_FILE_SIZE
) {
177 while (ofs
< CIFS_MF_SYMLINK_FILE_SIZE
) {
186 couldbe_mf_symlink(const struct cifs_fattr
*fattr
)
188 if (!S_ISREG(fattr
->cf_mode
))
189 /* it's not a symlink */
192 if (fattr
->cf_eof
!= CIFS_MF_SYMLINK_FILE_SIZE
)
193 /* it's not a symlink */
200 create_mf_symlink(const unsigned int xid
, struct cifs_tcon
*tcon
,
201 struct cifs_sb_info
*cifs_sb
, const char *fromName
,
206 unsigned int bytes_written
= 0;
208 buf
= kmalloc(CIFS_MF_SYMLINK_FILE_SIZE
, GFP_KERNEL
);
212 rc
= format_mf_symlink(buf
, CIFS_MF_SYMLINK_FILE_SIZE
, toName
);
216 if (tcon
->ses
->server
->ops
->create_mf_symlink
)
217 rc
= tcon
->ses
->server
->ops
->create_mf_symlink(xid
, tcon
,
218 cifs_sb
, fromName
, buf
, &bytes_written
);
225 if (bytes_written
!= CIFS_MF_SYMLINK_FILE_SIZE
)
233 query_mf_symlink(const unsigned int xid
, struct cifs_tcon
*tcon
,
234 struct cifs_sb_info
*cifs_sb
, const unsigned char *path
,
239 unsigned int link_len
= 0;
240 unsigned int bytes_read
= 0;
242 buf
= kmalloc(CIFS_MF_SYMLINK_FILE_SIZE
, GFP_KERNEL
);
246 if (tcon
->ses
->server
->ops
->query_mf_symlink
)
247 rc
= tcon
->ses
->server
->ops
->query_mf_symlink(xid
, tcon
,
248 cifs_sb
, path
, buf
, &bytes_read
);
255 if (bytes_read
== 0) { /* not a symlink */
260 rc
= parse_mf_symlink(buf
, bytes_read
, &link_len
, symlinkinfo
);
267 check_mf_symlink(unsigned int xid
, struct cifs_tcon
*tcon
,
268 struct cifs_sb_info
*cifs_sb
, struct cifs_fattr
*fattr
,
269 const unsigned char *path
)
273 unsigned int link_len
= 0;
274 unsigned int bytes_read
= 0;
276 if (!couldbe_mf_symlink(fattr
))
277 /* it's not a symlink */
280 buf
= kmalloc(CIFS_MF_SYMLINK_FILE_SIZE
, GFP_KERNEL
);
284 if (tcon
->ses
->server
->ops
->query_mf_symlink
)
285 rc
= tcon
->ses
->server
->ops
->query_mf_symlink(xid
, tcon
,
286 cifs_sb
, path
, buf
, &bytes_read
);
293 if (bytes_read
== 0) /* not a symlink */
296 rc
= parse_mf_symlink(buf
, bytes_read
, &link_len
, NULL
);
298 /* it's not a symlink */
306 /* it is a symlink */
307 fattr
->cf_eof
= link_len
;
308 fattr
->cf_mode
&= ~S_IFMT
;
309 fattr
->cf_mode
|= S_IFLNK
| S_IRWXU
| S_IRWXG
| S_IRWXO
;
310 fattr
->cf_dtype
= DT_LNK
;
317 * SMB 1.0 Protocol specific functions
321 cifs_query_mf_symlink(unsigned int xid
, struct cifs_tcon
*tcon
,
322 struct cifs_sb_info
*cifs_sb
, const unsigned char *path
,
323 char *pbuf
, unsigned int *pbytes_read
)
328 struct cifs_open_parms oparms
;
329 struct cifs_io_parms io_parms
;
330 int buf_type
= CIFS_NO_BUFFER
;
331 FILE_ALL_INFO file_info
;
334 oparms
.cifs_sb
= cifs_sb
;
335 oparms
.desired_access
= GENERIC_READ
;
336 oparms
.create_options
= CREATE_NOT_DIR
;
337 oparms
.disposition
= FILE_OPEN
;
340 oparms
.reconnect
= false;
342 rc
= CIFS_open(xid
, &oparms
, &oplock
, &file_info
);
346 if (file_info
.EndOfFile
!= cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE
)) {
348 /* it's not a symlink */
352 io_parms
.netfid
= fid
.netfid
;
353 io_parms
.pid
= current
->tgid
;
354 io_parms
.tcon
= tcon
;
356 io_parms
.length
= CIFS_MF_SYMLINK_FILE_SIZE
;
358 rc
= CIFSSMBRead(xid
, &io_parms
, pbytes_read
, &pbuf
, &buf_type
);
360 CIFSSMBClose(xid
, tcon
, fid
.netfid
);
365 cifs_create_mf_symlink(unsigned int xid
, struct cifs_tcon
*tcon
,
366 struct cifs_sb_info
*cifs_sb
, const unsigned char *path
,
367 char *pbuf
, unsigned int *pbytes_written
)
372 struct cifs_open_parms oparms
;
373 struct cifs_io_parms io_parms
;
374 int create_options
= CREATE_NOT_DIR
;
376 if (backup_cred(cifs_sb
))
377 create_options
|= CREATE_OPEN_BACKUP_INTENT
;
380 oparms
.cifs_sb
= cifs_sb
;
381 oparms
.desired_access
= GENERIC_WRITE
;
382 oparms
.create_options
= create_options
;
383 oparms
.disposition
= FILE_CREATE
;
386 oparms
.reconnect
= false;
388 rc
= CIFS_open(xid
, &oparms
, &oplock
, NULL
);
392 io_parms
.netfid
= fid
.netfid
;
393 io_parms
.pid
= current
->tgid
;
394 io_parms
.tcon
= tcon
;
396 io_parms
.length
= CIFS_MF_SYMLINK_FILE_SIZE
;
398 rc
= CIFSSMBWrite(xid
, &io_parms
, pbytes_written
, pbuf
, NULL
, 0);
399 CIFSSMBClose(xid
, tcon
, fid
.netfid
);
404 * M-F Symlink Functions - End
408 cifs_hardlink(struct dentry
*old_file
, struct inode
*inode
,
409 struct dentry
*direntry
)
413 char *from_name
= NULL
;
414 char *to_name
= NULL
;
415 struct cifs_sb_info
*cifs_sb
= CIFS_SB(inode
->i_sb
);
416 struct tcon_link
*tlink
;
417 struct cifs_tcon
*tcon
;
418 struct TCP_Server_Info
*server
;
419 struct cifsInodeInfo
*cifsInode
;
421 tlink
= cifs_sb_tlink(cifs_sb
);
423 return PTR_ERR(tlink
);
424 tcon
= tlink_tcon(tlink
);
428 from_name
= build_path_from_dentry(old_file
);
429 to_name
= build_path_from_dentry(direntry
);
430 if ((from_name
== NULL
) || (to_name
== NULL
)) {
436 rc
= CIFSUnixCreateHardLink(xid
, tcon
, from_name
, to_name
,
438 cifs_sb
->mnt_cifs_flags
&
439 CIFS_MOUNT_MAP_SPECIAL_CHR
);
441 server
= tcon
->ses
->server
;
442 if (!server
->ops
->create_hardlink
) {
446 rc
= server
->ops
->create_hardlink(xid
, tcon
, from_name
, to_name
,
448 if ((rc
== -EIO
) || (rc
== -EINVAL
))
452 d_drop(direntry
); /* force new lookup from server of target */
455 * if source file is cached (oplocked) revalidate will not go to server
456 * until the file is closed or oplock broken so update nlinks locally
458 if (old_file
->d_inode
) {
459 cifsInode
= CIFS_I(old_file
->d_inode
);
461 spin_lock(&old_file
->d_inode
->i_lock
);
462 inc_nlink(old_file
->d_inode
);
463 spin_unlock(&old_file
->d_inode
->i_lock
);
465 * BB should we make this contingent on superblock flag
468 /* old_file->d_inode->i_ctime = CURRENT_TIME; */
470 * parent dir timestamps will update from srv within a
471 * second, would it really be worth it to set the parent
472 * dir cifs inode time to zero to force revalidate
473 * (faster) for it too?
477 * if not oplocked will force revalidate to get info on source
483 * Will update parent dir timestamps from srv within a second.
484 * Would it really be worth it to set the parent dir (cifs
485 * inode) time field to zero to force revalidate on parent
486 * directory faster ie
488 * CIFS_I(inode)->time = 0;
496 cifs_put_tlink(tlink
);
501 cifs_follow_link(struct dentry
*direntry
, struct nameidata
*nd
)
503 struct inode
*inode
= direntry
->d_inode
;
506 char *full_path
= NULL
;
507 char *target_path
= NULL
;
508 struct cifs_sb_info
*cifs_sb
= CIFS_SB(inode
->i_sb
);
509 struct tcon_link
*tlink
= NULL
;
510 struct cifs_tcon
*tcon
;
511 struct TCP_Server_Info
*server
;
515 tlink
= cifs_sb_tlink(cifs_sb
);
521 tcon
= tlink_tcon(tlink
);
522 server
= tcon
->ses
->server
;
524 full_path
= build_path_from_dentry(direntry
);
528 cifs_dbg(FYI
, "Full path: %s inode = 0x%p\n", full_path
, inode
);
532 * First try Minshall+French Symlinks, if configured
533 * and fallback to UNIX Extensions Symlinks.
535 if (cifs_sb
->mnt_cifs_flags
& CIFS_MOUNT_MF_SYMLINKS
)
536 rc
= query_mf_symlink(xid
, tcon
, cifs_sb
, full_path
,
539 if (rc
!= 0 && server
->ops
->query_symlink
)
540 rc
= server
->ops
->query_symlink(xid
, tcon
, full_path
,
541 &target_path
, cifs_sb
);
547 target_path
= ERR_PTR(rc
);
552 cifs_put_tlink(tlink
);
553 nd_set_link(nd
, target_path
);
558 cifs_symlink(struct inode
*inode
, struct dentry
*direntry
, const char *symname
)
560 int rc
= -EOPNOTSUPP
;
562 struct cifs_sb_info
*cifs_sb
= CIFS_SB(inode
->i_sb
);
563 struct tcon_link
*tlink
;
564 struct cifs_tcon
*pTcon
;
565 char *full_path
= NULL
;
566 struct inode
*newinode
= NULL
;
570 tlink
= cifs_sb_tlink(cifs_sb
);
575 pTcon
= tlink_tcon(tlink
);
577 full_path
= build_path_from_dentry(direntry
);
578 if (full_path
== NULL
) {
583 cifs_dbg(FYI
, "Full path: %s\n", full_path
);
584 cifs_dbg(FYI
, "symname is %s\n", symname
);
586 /* BB what if DFS and this volume is on different share? BB */
587 if (cifs_sb
->mnt_cifs_flags
& CIFS_MOUNT_MF_SYMLINKS
)
588 rc
= create_mf_symlink(xid
, pTcon
, cifs_sb
, full_path
, symname
);
589 else if (pTcon
->unix_ext
)
590 rc
= CIFSUnixCreateSymLink(xid
, pTcon
, full_path
, symname
,
593 rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
594 cifs_sb_target->local_nls); */
598 rc
= cifs_get_inode_info_unix(&newinode
, full_path
,
601 rc
= cifs_get_inode_info(&newinode
, full_path
, NULL
,
602 inode
->i_sb
, xid
, NULL
);
605 cifs_dbg(FYI
, "Create symlink ok, getinodeinfo fail rc = %d\n",
608 d_instantiate(direntry
, newinode
);
613 cifs_put_tlink(tlink
);