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 if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
103 rc = symlink_hash(link_len, link_str, md5_hash);
105 cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
109 scnprintf(md5_str2, sizeof(md5_str2),
110 CIFS_MF_SYMLINK_MD5_FORMAT,
111 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
113 if (strncmp(md5_str1, md5_str2, 17) != 0)
117 *_link_str = kstrndup(link_str, link_len, GFP_KERNEL);
122 *_link_len = link_len;
127 format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str)
130 unsigned int link_len;
134 if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
137 link_len = strlen(link_str);
139 if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
140 return -ENAMETOOLONG;
142 rc = symlink_hash(link_len, link_str, md5_hash);
144 cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
148 scnprintf(buf, buf_len,
149 CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT,
151 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
153 ofs = CIFS_MF_SYMLINK_LINK_OFFSET;
154 memcpy(buf + ofs, link_str, link_len);
157 if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
162 while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
171 couldbe_mf_symlink(const struct cifs_fattr *fattr)
173 if (!S_ISREG(fattr->cf_mode))
174 /* it's not a symlink */
177 if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE)
178 /* it's not a symlink */
185 create_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
186 struct cifs_sb_info *cifs_sb, const char *fromName,
191 unsigned int bytes_written = 0;
193 buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
197 rc = format_mf_symlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName);
201 if (tcon->ses->server->ops->create_mf_symlink)
202 rc = tcon->ses->server->ops->create_mf_symlink(xid, tcon,
203 cifs_sb, fromName, buf, &bytes_written);
210 if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE)
218 query_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
219 struct cifs_sb_info *cifs_sb, const unsigned char *path,
224 unsigned int link_len = 0;
225 unsigned int bytes_read = 0;
227 buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
231 if (tcon->ses->server->ops->query_mf_symlink)
232 rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
233 cifs_sb, path, buf, &bytes_read);
240 if (bytes_read == 0) { /* not a symlink */
245 rc = parse_mf_symlink(buf, bytes_read, &link_len, symlinkinfo);
252 check_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
253 struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr,
254 const unsigned char *path)
258 unsigned int link_len = 0;
259 unsigned int bytes_read = 0;
261 if (!couldbe_mf_symlink(fattr))
262 /* it's not a symlink */
265 buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
269 if (tcon->ses->server->ops->query_mf_symlink)
270 rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
271 cifs_sb, path, buf, &bytes_read);
278 if (bytes_read == 0) /* not a symlink */
281 rc = parse_mf_symlink(buf, bytes_read, &link_len, NULL);
283 /* it's not a symlink */
291 /* it is a symlink */
292 fattr->cf_eof = link_len;
293 fattr->cf_mode &= ~S_IFMT;
294 fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO;
295 fattr->cf_dtype = DT_LNK;
302 * SMB 1.0 Protocol specific functions
306 cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
307 struct cifs_sb_info *cifs_sb, const unsigned char *path,
308 char *pbuf, unsigned int *pbytes_read)
313 struct cifs_open_parms oparms;
314 struct cifs_io_parms io_parms = {0};
315 int buf_type = CIFS_NO_BUFFER;
316 FILE_ALL_INFO file_info;
319 oparms.cifs_sb = cifs_sb;
320 oparms.desired_access = GENERIC_READ;
321 oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
322 oparms.disposition = FILE_OPEN;
325 oparms.reconnect = false;
327 rc = CIFS_open(xid, &oparms, &oplock, &file_info);
331 if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
333 /* it's not a symlink */
337 io_parms.netfid = fid.netfid;
338 io_parms.pid = current->tgid;
339 io_parms.tcon = tcon;
341 io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
343 rc = CIFSSMBRead(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
345 CIFSSMBClose(xid, tcon, fid.netfid);
350 cifs_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
351 struct cifs_sb_info *cifs_sb, const unsigned char *path,
352 char *pbuf, unsigned int *pbytes_written)
357 struct cifs_open_parms oparms;
358 struct cifs_io_parms io_parms = {0};
361 oparms.cifs_sb = cifs_sb;
362 oparms.desired_access = GENERIC_WRITE;
363 oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
364 oparms.disposition = FILE_CREATE;
367 oparms.reconnect = false;
369 rc = CIFS_open(xid, &oparms, &oplock, NULL);
373 io_parms.netfid = fid.netfid;
374 io_parms.pid = current->tgid;
375 io_parms.tcon = tcon;
377 io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
379 rc = CIFSSMBWrite(xid, &io_parms, pbytes_written, pbuf);
380 CIFSSMBClose(xid, tcon, fid.netfid);
385 * SMB 2.1/SMB3 Protocol specific functions
388 smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
389 struct cifs_sb_info *cifs_sb, const unsigned char *path,
390 char *pbuf, unsigned int *pbytes_read)
394 struct cifs_open_parms oparms;
395 struct cifs_io_parms io_parms = {0};
396 int buf_type = CIFS_NO_BUFFER;
398 __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
399 struct smb2_file_all_info *pfile_info = NULL;
402 oparms.cifs_sb = cifs_sb;
403 oparms.desired_access = GENERIC_READ;
404 oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
405 oparms.disposition = FILE_OPEN;
407 oparms.reconnect = false;
409 utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
410 if (utf16_path == NULL)
413 pfile_info = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
416 if (pfile_info == NULL) {
421 rc = SMB2_open(xid, &oparms, utf16_path, &oplock, pfile_info, NULL,
424 goto qmf_out_open_fail;
426 if (pfile_info->EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
427 /* it's not a symlink */
428 rc = -ENOENT; /* Is there a better rc to return? */
432 io_parms.netfid = fid.netfid;
433 io_parms.pid = current->tgid;
434 io_parms.tcon = tcon;
436 io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
437 io_parms.persistent_fid = fid.persistent_fid;
438 io_parms.volatile_fid = fid.volatile_fid;
439 rc = SMB2_read(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
441 SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
449 smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
450 struct cifs_sb_info *cifs_sb, const unsigned char *path,
451 char *pbuf, unsigned int *pbytes_written)
455 struct cifs_open_parms oparms;
456 struct cifs_io_parms io_parms = {0};
458 __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
461 cifs_dbg(FYI, "%s: path: %s\n", __func__, path);
463 utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
468 oparms.cifs_sb = cifs_sb;
469 oparms.desired_access = GENERIC_WRITE;
470 oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
471 oparms.disposition = FILE_CREATE;
473 oparms.reconnect = false;
476 rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL,
483 io_parms.netfid = fid.netfid;
484 io_parms.pid = current->tgid;
485 io_parms.tcon = tcon;
487 io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
488 io_parms.persistent_fid = fid.persistent_fid;
489 io_parms.volatile_fid = fid.volatile_fid;
491 /* iov[0] is reserved for smb header */
492 iov[1].iov_base = pbuf;
493 iov[1].iov_len = CIFS_MF_SYMLINK_FILE_SIZE;
495 rc = SMB2_write(xid, &io_parms, pbytes_written, iov, 1);
497 /* Make sure we wrote all of the symlink data */
498 if ((rc == 0) && (*pbytes_written != CIFS_MF_SYMLINK_FILE_SIZE))
501 SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
508 * M-F Symlink Functions - End
512 cifs_hardlink(struct dentry *old_file, struct inode *inode,
513 struct dentry *direntry)
517 char *from_name = NULL;
518 char *to_name = NULL;
519 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
520 struct tcon_link *tlink;
521 struct cifs_tcon *tcon;
522 struct TCP_Server_Info *server;
523 struct cifsInodeInfo *cifsInode;
525 tlink = cifs_sb_tlink(cifs_sb);
527 return PTR_ERR(tlink);
528 tcon = tlink_tcon(tlink);
532 from_name = build_path_from_dentry(old_file);
533 to_name = build_path_from_dentry(direntry);
534 if ((from_name == NULL) || (to_name == NULL)) {
540 rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name,
542 cifs_remap(cifs_sb));
544 server = tcon->ses->server;
545 if (!server->ops->create_hardlink) {
549 rc = server->ops->create_hardlink(xid, tcon, from_name, to_name,
551 if ((rc == -EIO) || (rc == -EINVAL))
555 d_drop(direntry); /* force new lookup from server of target */
558 * if source file is cached (oplocked) revalidate will not go to server
559 * until the file is closed or oplock broken so update nlinks locally
561 if (d_really_is_positive(old_file)) {
562 cifsInode = CIFS_I(d_inode(old_file));
564 spin_lock(&d_inode(old_file)->i_lock);
565 inc_nlink(d_inode(old_file));
566 spin_unlock(&d_inode(old_file)->i_lock);
569 * parent dir timestamps will update from srv within a
570 * second, would it really be worth it to set the parent
571 * dir cifs inode time to zero to force revalidate
572 * (faster) for it too?
576 * if not oplocked will force revalidate to get info on source
577 * file from srv. Note Samba server prior to 4.2 has bug -
578 * not updating src file ctime on hardlinks but Windows servers
584 * Will update parent dir timestamps from srv within a second.
585 * Would it really be worth it to set the parent dir (cifs
586 * inode) time field to zero to force revalidate on parent
587 * directory faster ie
589 * CIFS_I(inode)->time = 0;
597 cifs_put_tlink(tlink);
602 cifs_get_link(struct dentry *direntry, struct inode *inode,
603 struct delayed_call *done)
607 char *full_path = NULL;
608 char *target_path = NULL;
609 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
610 struct tcon_link *tlink = NULL;
611 struct cifs_tcon *tcon;
612 struct TCP_Server_Info *server;
615 return ERR_PTR(-ECHILD);
619 tlink = cifs_sb_tlink(cifs_sb);
622 return ERR_CAST(tlink);
624 tcon = tlink_tcon(tlink);
625 server = tcon->ses->server;
627 full_path = build_path_from_dentry(direntry);
630 cifs_put_tlink(tlink);
631 return ERR_PTR(-ENOMEM);
634 cifs_dbg(FYI, "Full path: %s inode = 0x%p\n", full_path, inode);
638 * First try Minshall+French Symlinks, if configured
639 * and fallback to UNIX Extensions Symlinks.
641 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
642 rc = query_mf_symlink(xid, tcon, cifs_sb, full_path,
645 if (rc != 0 && server->ops->query_symlink) {
646 struct cifsInodeInfo *cifsi = CIFS_I(inode);
647 bool reparse_point = false;
649 if (cifsi->cifsAttrs & ATTR_REPARSE)
650 reparse_point = true;
652 rc = server->ops->query_symlink(xid, tcon, cifs_sb, full_path,
653 &target_path, reparse_point);
658 cifs_put_tlink(tlink);
663 set_delayed_call(done, kfree_link, target_path);
668 cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname)
670 int rc = -EOPNOTSUPP;
672 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
673 struct tcon_link *tlink;
674 struct cifs_tcon *pTcon;
675 char *full_path = NULL;
676 struct inode *newinode = NULL;
680 tlink = cifs_sb_tlink(cifs_sb);
685 pTcon = tlink_tcon(tlink);
687 full_path = build_path_from_dentry(direntry);
688 if (full_path == NULL) {
693 cifs_dbg(FYI, "Full path: %s\n", full_path);
694 cifs_dbg(FYI, "symname is %s\n", symname);
696 /* BB what if DFS and this volume is on different share? BB */
697 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
698 rc = create_mf_symlink(xid, pTcon, cifs_sb, full_path, symname);
699 else if (pTcon->unix_ext)
700 rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
702 cifs_remap(cifs_sb));
704 rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
705 cifs_sb_target->local_nls); */
708 if (pTcon->posix_extensions)
709 rc = smb311_posix_get_inode_info(&newinode, full_path, inode->i_sb, xid);
710 else if (pTcon->unix_ext)
711 rc = cifs_get_inode_info_unix(&newinode, full_path,
714 rc = cifs_get_inode_info(&newinode, full_path, NULL,
715 inode->i_sb, xid, NULL);
718 cifs_dbg(FYI, "Create symlink ok, getinodeinfo fail rc = %d\n",
721 d_instantiate(direntry, newinode);
726 cifs_put_tlink(tlink);