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"
31 #include "cifs_unicode.h"
32 #include "smb2proto.h"
35 * M-F Symlink Functions - Begin
38 #define CIFS_MF_SYMLINK_LEN_OFFSET (4+1)
39 #define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1))
40 #define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1))
41 #define CIFS_MF_SYMLINK_LINK_MAXLEN (1024)
42 #define CIFS_MF_SYMLINK_FILE_SIZE \
43 (CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN)
45 #define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n"
46 #define CIFS_MF_SYMLINK_MD5_FORMAT "%16phN\n"
47 #define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) md5_hash
50 symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
53 struct crypto_shash *md5 = NULL;
54 struct sdesc *sdescmd5 = NULL;
56 rc = cifs_alloc_hash("md5", &md5, &sdescmd5);
58 goto symlink_hash_err;
60 rc = crypto_shash_init(&sdescmd5->shash);
62 cifs_dbg(VFS, "%s: Could not init md5 shash\n", __func__);
63 goto symlink_hash_err;
65 rc = crypto_shash_update(&sdescmd5->shash, link_str, link_len);
67 cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__);
68 goto symlink_hash_err;
70 rc = crypto_shash_final(&sdescmd5->shash, md5_hash);
72 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
75 cifs_free_hash(&md5, &sdescmd5);
80 parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len,
84 unsigned int link_len;
90 if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
93 md5_str1 = (const char *)&buf[CIFS_MF_SYMLINK_MD5_OFFSET];
94 link_str = (const char *)&buf[CIFS_MF_SYMLINK_LINK_OFFSET];
96 rc = sscanf(buf, CIFS_MF_SYMLINK_LEN_FORMAT, &link_len);
100 rc = symlink_hash(link_len, link_str, md5_hash);
102 cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
106 scnprintf(md5_str2, sizeof(md5_str2),
107 CIFS_MF_SYMLINK_MD5_FORMAT,
108 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
110 if (strncmp(md5_str1, md5_str2, 17) != 0)
114 *_link_str = kstrndup(link_str, link_len, GFP_KERNEL);
119 *_link_len = link_len;
124 format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str)
127 unsigned int link_len;
131 if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
134 link_len = strlen(link_str);
136 if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
137 return -ENAMETOOLONG;
139 rc = symlink_hash(link_len, link_str, md5_hash);
141 cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
145 scnprintf(buf, buf_len,
146 CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT,
148 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
150 ofs = CIFS_MF_SYMLINK_LINK_OFFSET;
151 memcpy(buf + ofs, link_str, link_len);
154 if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
159 while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
168 couldbe_mf_symlink(const struct cifs_fattr *fattr)
170 if (!S_ISREG(fattr->cf_mode))
171 /* it's not a symlink */
174 if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE)
175 /* it's not a symlink */
182 create_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
183 struct cifs_sb_info *cifs_sb, const char *fromName,
188 unsigned int bytes_written = 0;
190 buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
194 rc = format_mf_symlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName);
198 if (tcon->ses->server->ops->create_mf_symlink)
199 rc = tcon->ses->server->ops->create_mf_symlink(xid, tcon,
200 cifs_sb, fromName, buf, &bytes_written);
207 if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE)
215 query_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
216 struct cifs_sb_info *cifs_sb, const unsigned char *path,
221 unsigned int link_len = 0;
222 unsigned int bytes_read = 0;
224 buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
228 if (tcon->ses->server->ops->query_mf_symlink)
229 rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
230 cifs_sb, path, buf, &bytes_read);
237 if (bytes_read == 0) { /* not a symlink */
242 rc = parse_mf_symlink(buf, bytes_read, &link_len, symlinkinfo);
249 check_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
250 struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr,
251 const unsigned char *path)
255 unsigned int link_len = 0;
256 unsigned int bytes_read = 0;
258 if (!couldbe_mf_symlink(fattr))
259 /* it's not a symlink */
262 buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
266 if (tcon->ses->server->ops->query_mf_symlink)
267 rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
268 cifs_sb, path, buf, &bytes_read);
275 if (bytes_read == 0) /* not a symlink */
278 rc = parse_mf_symlink(buf, bytes_read, &link_len, NULL);
280 /* it's not a symlink */
288 /* it is a symlink */
289 fattr->cf_eof = link_len;
290 fattr->cf_mode &= ~S_IFMT;
291 fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO;
292 fattr->cf_dtype = DT_LNK;
299 * SMB 1.0 Protocol specific functions
303 cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
304 struct cifs_sb_info *cifs_sb, const unsigned char *path,
305 char *pbuf, unsigned int *pbytes_read)
310 struct cifs_open_parms oparms;
311 struct cifs_io_parms io_parms = {0};
312 int buf_type = CIFS_NO_BUFFER;
313 FILE_ALL_INFO file_info;
316 oparms.cifs_sb = cifs_sb;
317 oparms.desired_access = GENERIC_READ;
318 oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
319 oparms.disposition = FILE_OPEN;
322 oparms.reconnect = false;
324 rc = CIFS_open(xid, &oparms, &oplock, &file_info);
328 if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
330 /* it's not a symlink */
334 io_parms.netfid = fid.netfid;
335 io_parms.pid = current->tgid;
336 io_parms.tcon = tcon;
338 io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
340 rc = CIFSSMBRead(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
342 CIFSSMBClose(xid, tcon, fid.netfid);
347 cifs_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
348 struct cifs_sb_info *cifs_sb, const unsigned char *path,
349 char *pbuf, unsigned int *pbytes_written)
354 struct cifs_open_parms oparms;
355 struct cifs_io_parms io_parms = {0};
358 oparms.cifs_sb = cifs_sb;
359 oparms.desired_access = GENERIC_WRITE;
360 oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
361 oparms.disposition = FILE_CREATE;
364 oparms.reconnect = false;
366 rc = CIFS_open(xid, &oparms, &oplock, NULL);
370 io_parms.netfid = fid.netfid;
371 io_parms.pid = current->tgid;
372 io_parms.tcon = tcon;
374 io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
376 rc = CIFSSMBWrite(xid, &io_parms, pbytes_written, pbuf);
377 CIFSSMBClose(xid, tcon, fid.netfid);
382 * SMB 2.1/SMB3 Protocol specific functions
385 smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
386 struct cifs_sb_info *cifs_sb, const unsigned char *path,
387 char *pbuf, unsigned int *pbytes_read)
391 struct cifs_open_parms oparms;
392 struct cifs_io_parms io_parms = {0};
393 int buf_type = CIFS_NO_BUFFER;
395 __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
396 struct smb2_file_all_info *pfile_info = NULL;
399 oparms.cifs_sb = cifs_sb;
400 oparms.desired_access = GENERIC_READ;
401 oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
402 oparms.disposition = FILE_OPEN;
404 oparms.reconnect = false;
406 utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
407 if (utf16_path == NULL)
410 pfile_info = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
413 if (pfile_info == NULL) {
418 rc = SMB2_open(xid, &oparms, utf16_path, &oplock, pfile_info, NULL,
421 goto qmf_out_open_fail;
423 if (pfile_info->EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
424 /* it's not a symlink */
425 rc = -ENOENT; /* Is there a better rc to return? */
429 io_parms.netfid = fid.netfid;
430 io_parms.pid = current->tgid;
431 io_parms.tcon = tcon;
433 io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
434 io_parms.persistent_fid = fid.persistent_fid;
435 io_parms.volatile_fid = fid.volatile_fid;
436 rc = SMB2_read(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
438 SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
446 smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
447 struct cifs_sb_info *cifs_sb, const unsigned char *path,
448 char *pbuf, unsigned int *pbytes_written)
452 struct cifs_open_parms oparms;
453 struct cifs_io_parms io_parms = {0};
455 __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
458 cifs_dbg(FYI, "%s: path: %s\n", __func__, path);
460 utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
465 oparms.cifs_sb = cifs_sb;
466 oparms.desired_access = GENERIC_WRITE;
467 oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
468 oparms.disposition = FILE_CREATE;
470 oparms.reconnect = false;
472 rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL,
479 io_parms.netfid = fid.netfid;
480 io_parms.pid = current->tgid;
481 io_parms.tcon = tcon;
483 io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
484 io_parms.persistent_fid = fid.persistent_fid;
485 io_parms.volatile_fid = fid.volatile_fid;
487 /* iov[0] is reserved for smb header */
488 iov[1].iov_base = pbuf;
489 iov[1].iov_len = CIFS_MF_SYMLINK_FILE_SIZE;
491 rc = SMB2_write(xid, &io_parms, pbytes_written, iov, 1);
493 /* Make sure we wrote all of the symlink data */
494 if ((rc == 0) && (*pbytes_written != CIFS_MF_SYMLINK_FILE_SIZE))
497 SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
504 * M-F Symlink Functions - End
508 cifs_hardlink(struct dentry *old_file, struct inode *inode,
509 struct dentry *direntry)
513 const char *from_name, *to_name;
515 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
516 struct tcon_link *tlink;
517 struct cifs_tcon *tcon;
518 struct TCP_Server_Info *server;
519 struct cifsInodeInfo *cifsInode;
521 tlink = cifs_sb_tlink(cifs_sb);
523 return PTR_ERR(tlink);
524 tcon = tlink_tcon(tlink);
527 page1 = alloc_dentry_path();
528 page2 = alloc_dentry_path();
530 from_name = build_path_from_dentry(old_file, page1);
531 if (IS_ERR(from_name)) {
532 rc = PTR_ERR(from_name);
535 to_name = build_path_from_dentry(direntry, page2);
536 if (IS_ERR(to_name)) {
537 rc = PTR_ERR(to_name);
542 rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name,
544 cifs_remap(cifs_sb));
546 server = tcon->ses->server;
547 if (!server->ops->create_hardlink) {
551 rc = server->ops->create_hardlink(xid, tcon, from_name, to_name,
553 if ((rc == -EIO) || (rc == -EINVAL))
557 d_drop(direntry); /* force new lookup from server of target */
560 * if source file is cached (oplocked) revalidate will not go to server
561 * until the file is closed or oplock broken so update nlinks locally
563 if (d_really_is_positive(old_file)) {
564 cifsInode = CIFS_I(d_inode(old_file));
566 spin_lock(&d_inode(old_file)->i_lock);
567 inc_nlink(d_inode(old_file));
568 spin_unlock(&d_inode(old_file)->i_lock);
571 * parent dir timestamps will update from srv within a
572 * second, would it really be worth it to set the parent
573 * dir cifs inode time to zero to force revalidate
574 * (faster) for it too?
578 * if not oplocked will force revalidate to get info on source
579 * file from srv. Note Samba server prior to 4.2 has bug -
580 * not updating src file ctime on hardlinks but Windows servers
586 * Will update parent dir timestamps from srv within a second.
587 * Would it really be worth it to set the parent dir (cifs
588 * inode) time field to zero to force revalidate on parent
589 * directory faster ie
591 * CIFS_I(inode)->time = 0;
596 free_dentry_path(page1);
597 free_dentry_path(page2);
599 cifs_put_tlink(tlink);
604 cifs_get_link(struct dentry *direntry, struct inode *inode,
605 struct delayed_call *done)
609 const char *full_path;
611 char *target_path = NULL;
612 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
613 struct tcon_link *tlink = NULL;
614 struct cifs_tcon *tcon;
615 struct TCP_Server_Info *server;
618 return ERR_PTR(-ECHILD);
622 tlink = cifs_sb_tlink(cifs_sb);
625 return ERR_CAST(tlink);
627 tcon = tlink_tcon(tlink);
628 server = tcon->ses->server;
630 page = alloc_dentry_path();
631 full_path = build_path_from_dentry(direntry, page);
632 if (IS_ERR(full_path)) {
634 cifs_put_tlink(tlink);
635 free_dentry_path(page);
636 return ERR_CAST(full_path);
639 cifs_dbg(FYI, "Full path: %s inode = 0x%p\n", full_path, inode);
643 * First try Minshall+French Symlinks, if configured
644 * and fallback to UNIX Extensions Symlinks.
646 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
647 rc = query_mf_symlink(xid, tcon, cifs_sb, full_path,
650 if (rc != 0 && server->ops->query_symlink) {
651 struct cifsInodeInfo *cifsi = CIFS_I(inode);
652 bool reparse_point = false;
654 if (cifsi->cifsAttrs & ATTR_REPARSE)
655 reparse_point = true;
657 rc = server->ops->query_symlink(xid, tcon, cifs_sb, full_path,
658 &target_path, reparse_point);
661 free_dentry_path(page);
663 cifs_put_tlink(tlink);
668 set_delayed_call(done, kfree_link, target_path);
673 cifs_symlink(struct user_namespace *mnt_userns, struct inode *inode,
674 struct dentry *direntry, const char *symname)
676 int rc = -EOPNOTSUPP;
678 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
679 struct tcon_link *tlink;
680 struct cifs_tcon *pTcon;
681 const char *full_path;
682 void *page = alloc_dentry_path();
683 struct inode *newinode = NULL;
687 tlink = cifs_sb_tlink(cifs_sb);
692 pTcon = tlink_tcon(tlink);
694 full_path = build_path_from_dentry(direntry, page);
695 if (IS_ERR(full_path)) {
696 rc = PTR_ERR(full_path);
700 cifs_dbg(FYI, "Full path: %s\n", full_path);
701 cifs_dbg(FYI, "symname is %s\n", symname);
703 /* BB what if DFS and this volume is on different share? BB */
704 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
705 rc = create_mf_symlink(xid, pTcon, cifs_sb, full_path, symname);
706 else if (pTcon->unix_ext)
707 rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
709 cifs_remap(cifs_sb));
711 rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
712 cifs_sb_target->local_nls); */
715 if (pTcon->posix_extensions)
716 rc = smb311_posix_get_inode_info(&newinode, full_path, inode->i_sb, xid);
717 else if (pTcon->unix_ext)
718 rc = cifs_get_inode_info_unix(&newinode, full_path,
721 rc = cifs_get_inode_info(&newinode, full_path, NULL,
722 inode->i_sb, xid, NULL);
725 cifs_dbg(FYI, "Create symlink ok, getinodeinfo fail rc = %d\n",
728 d_instantiate(direntry, newinode);
732 free_dentry_path(page);
733 cifs_put_tlink(tlink);