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 CIFSQueryMFSymLink(const int xid, struct cifsTconInfo *tcon,
96 const unsigned char *searchName, char **symlinkinfo,
97 const struct nls_table *nls_codepage, int remap)
104 unsigned int bytes_read = 0;
105 int buf_type = CIFS_NO_BUFFER;
106 unsigned int link_len = 0;
107 FILE_ALL_INFO file_info;
109 rc = CIFSSMBOpen(xid, tcon, searchName, FILE_OPEN, GENERIC_READ,
110 CREATE_NOT_DIR, &netfid, &oplock, &file_info,
111 nls_codepage, remap);
115 if (file_info.EndOfFile != CIFS_MF_SYMLINK_FILE_SIZE) {
116 CIFSSMBClose(xid, tcon, netfid);
117 /* it's not a symlink */
121 buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
126 rc = CIFSSMBRead(xid, tcon, netfid,
127 CIFS_MF_SYMLINK_FILE_SIZE /* length */,
129 &bytes_read, &pbuf, &buf_type);
130 CIFSSMBClose(xid, tcon, netfid);
136 rc = CIFSParseMFSymlink(buf, bytes_read, &link_len, symlinkinfo);
145 CIFSCouldBeMFSymlink(const struct cifs_fattr *fattr)
147 if (!(fattr->cf_mode & S_IFREG))
148 /* it's not a symlink */
151 if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE)
152 /* it's not a symlink */
159 CIFSCheckMFSymlink(struct cifs_fattr *fattr,
160 const unsigned char *path,
161 struct cifs_sb_info *cifs_sb, int xid)
166 struct cifsTconInfo *pTcon = cifs_sb->tcon;
169 unsigned int bytes_read = 0;
170 int buf_type = CIFS_NO_BUFFER;
171 unsigned int link_len = 0;
172 FILE_ALL_INFO file_info;
174 if (!CIFSCouldBeMFSymlink(fattr))
175 /* it's not a symlink */
178 rc = CIFSSMBOpen(xid, pTcon, path, FILE_OPEN, GENERIC_READ,
179 CREATE_NOT_DIR, &netfid, &oplock, &file_info,
181 cifs_sb->mnt_cifs_flags &
182 CIFS_MOUNT_MAP_SPECIAL_CHR);
186 if (file_info.EndOfFile != CIFS_MF_SYMLINK_FILE_SIZE) {
187 CIFSSMBClose(xid, pTcon, netfid);
188 /* it's not a symlink */
192 buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
197 rc = CIFSSMBRead(xid, pTcon, netfid,
198 CIFS_MF_SYMLINK_FILE_SIZE /* length */,
200 &bytes_read, &pbuf, &buf_type);
201 CIFSSMBClose(xid, pTcon, netfid);
207 rc = CIFSParseMFSymlink(buf, bytes_read, &link_len, NULL);
210 /* it's not a symlink */
215 /* it is a symlink */
216 fattr->cf_eof = link_len;
217 fattr->cf_mode &= ~S_IFMT;
218 fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO;
219 fattr->cf_dtype = DT_LNK;
224 cifs_hardlink(struct dentry *old_file, struct inode *inode,
225 struct dentry *direntry)
229 char *fromName = NULL;
231 struct cifs_sb_info *cifs_sb_target;
232 struct cifsTconInfo *pTcon;
233 struct cifsInodeInfo *cifsInode;
237 cifs_sb_target = CIFS_SB(inode->i_sb);
238 pTcon = cifs_sb_target->tcon;
240 /* No need to check for cross device links since server will do that
241 BB note DFS case in future though (when we may have to check) */
243 fromName = build_path_from_dentry(old_file);
244 toName = build_path_from_dentry(direntry);
245 if ((fromName == NULL) || (toName == NULL)) {
250 /* if (cifs_sb_target->tcon->ses->capabilities & CAP_UNIX)*/
252 rc = CIFSUnixCreateHardLink(xid, pTcon, fromName, toName,
253 cifs_sb_target->local_nls,
254 cifs_sb_target->mnt_cifs_flags &
255 CIFS_MOUNT_MAP_SPECIAL_CHR);
257 rc = CIFSCreateHardLink(xid, pTcon, fromName, toName,
258 cifs_sb_target->local_nls,
259 cifs_sb_target->mnt_cifs_flags &
260 CIFS_MOUNT_MAP_SPECIAL_CHR);
261 if ((rc == -EIO) || (rc == -EINVAL))
265 d_drop(direntry); /* force new lookup from server of target */
267 /* if source file is cached (oplocked) revalidate will not go to server
268 until the file is closed or oplock broken so update nlinks locally */
269 if (old_file->d_inode) {
270 cifsInode = CIFS_I(old_file->d_inode);
272 old_file->d_inode->i_nlink++;
273 /* BB should we make this contingent on superblock flag NOATIME? */
274 /* old_file->d_inode->i_ctime = CURRENT_TIME;*/
275 /* parent dir timestamps will update from srv
276 within a second, would it really be worth it
277 to set the parent dir cifs inode time to zero
278 to force revalidate (faster) for it too? */
280 /* if not oplocked will force revalidate to get info
281 on source file from srv */
284 /* Will update parent dir timestamps from srv within a second.
285 Would it really be worth it to set the parent dir (cifs
286 inode) time field to zero to force revalidate on parent
288 CIFS_I(inode)->time = 0; */
299 cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
301 struct inode *inode = direntry->d_inode;
304 char *full_path = NULL;
305 char *target_path = NULL;
306 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
307 struct cifsTconInfo *tcon = cifs_sb->tcon;
312 * For now, we just handle symlinks with unix extensions enabled.
313 * Eventually we should handle NTFS reparse points, and MacOS
314 * symlink support. For instance...
316 * rc = CIFSSMBQueryReparseLinkInfo(...)
318 * For now, just return -EACCES when the server doesn't support posix
319 * extensions. Note that we still allow querying symlinks when posix
320 * extensions are manually disabled. We could disable these as well
321 * but there doesn't seem to be any harm in allowing the client to
324 if (!(tcon->ses->capabilities & CAP_UNIX)) {
329 full_path = build_path_from_dentry(direntry);
333 cFYI(1, "Full path: %s inode = 0x%p", full_path, inode);
335 rc = CIFSSMBUnixQuerySymLink(xid, tcon, full_path, &target_path,
341 target_path = ERR_PTR(rc);
345 nd_set_link(nd, target_path);
350 cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname)
352 int rc = -EOPNOTSUPP;
354 struct cifs_sb_info *cifs_sb;
355 struct cifsTconInfo *pTcon;
356 char *full_path = NULL;
357 struct inode *newinode = NULL;
361 cifs_sb = CIFS_SB(inode->i_sb);
362 pTcon = cifs_sb->tcon;
364 full_path = build_path_from_dentry(direntry);
366 if (full_path == NULL) {
372 cFYI(1, "Full path: %s", full_path);
373 cFYI(1, "symname is %s", symname);
375 /* BB what if DFS and this volume is on different share? BB */
377 rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
380 rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
381 cifs_sb_target->local_nls); */
385 rc = cifs_get_inode_info_unix(&newinode, full_path,
388 rc = cifs_get_inode_info(&newinode, full_path, NULL,
389 inode->i_sb, xid, NULL);
392 cFYI(1, "Create symlink ok, getinodeinfo fail rc = %d",
396 direntry->d_op = &cifs_ci_dentry_ops;
398 direntry->d_op = &cifs_dentry_ops;
399 d_instantiate(direntry, newinode);
408 void cifs_put_link(struct dentry *direntry, struct nameidata *nd, void *cookie)
410 char *p = nd_get_link(nd);