1 /*
2 * fs/cifs/readdir.c
3 *
4 * Directory search handling
5 *
6 * Copyright (C) International Business Machines Corp., 2004, 2008
7 * Copyright (C) Red Hat, Inc., 2011
8 * Author(s): Steve French (sfrench@us.ibm.com)
9 *
10 * This library is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License as published
12 * by the Free Software Foundation; either version 2.1 of the License, or
13 * (at your option) any later version.
14 *
15 * This library is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
18 * the GNU Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this library; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 */
24 #include <linux/fs.h>
25 #include <linux/pagemap.h>
26 #include <linux/slab.h>
27 #include <linux/stat.h>
28 #include "cifspdu.h"
29 #include "cifsglob.h"
30 #include "cifsproto.h"
31 #include "cifs_unicode.h"
32 #include "cifs_debug.h"
33 #include "cifs_fs_sb.h"
34 #include "cifsfs.h"
35
36 /*
37 * To be safe - for UCS to UTF-8 with strings loaded with the rare long
38 * characters alloc more to account for such multibyte target UTF-8
39 * characters.
40 */
41 #define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2)
42
43 #ifdef CONFIG_CIFS_DEBUG2
dump_cifs_file_struct(struct file * file,char * label)44 static void dump_cifs_file_struct(struct file *file, char *label)
45 {
46 struct cifsFileInfo *cf;
47
48 if (file) {
49 cf = file->private_data;
50 if (cf == NULL) {
51 cifs_dbg(FYI, "empty cifs private file data\n");
52 return;
53 }
54 if (cf->invalidHandle)
55 cifs_dbg(FYI, "invalid handle\n");
56 if (cf->srch_inf.endOfSearch)
57 cifs_dbg(FYI, "end of search\n");
58 if (cf->srch_inf.emptyDir)
59 cifs_dbg(FYI, "empty dir\n");
60 }
61 }
62 #else
dump_cifs_file_struct(struct file * file,char * label)63 static inline void dump_cifs_file_struct(struct file *file, char *label)
64 {
65 }
66 #endif /* DEBUG2 */
67
68 /*
69 * Attempt to preload the dcache with the results from the FIND_FIRST/NEXT
70 *
71 * Find the dentry that matches "name". If there isn't one, create one. If it's
72 * a negative dentry or the uniqueid or filetype(mode) changed,
73 * then drop it and recreate it.
74 */
75 static void
cifs_prime_dcache(struct dentry * parent,struct qstr * name,struct cifs_fattr * fattr)76 cifs_prime_dcache(struct dentry *parent, struct qstr *name,
77 struct cifs_fattr *fattr)
78 {
79 struct dentry *dentry, *alias;
80 struct inode *inode;
81 struct super_block *sb = parent->d_sb;
82 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
83 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
84
85 cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
86
87 dentry = d_hash_and_lookup(parent, name);
88 if (!dentry) {
89 /*
90 * If we know that the inode will need to be revalidated
91 * immediately, then don't create a new dentry for it.
92 * We'll end up doing an on the wire call either way and
93 * this spares us an invalidation.
94 */
95 if (fattr->cf_flags & CIFS_FATTR_NEED_REVAL)
96 return;
97 retry:
98 dentry = d_alloc_parallel(parent, name, &wq);
99 }
100 if (IS_ERR(dentry))
101 return;
102 if (!d_in_lookup(dentry)) {
103 inode = d_inode(dentry);
104 if (inode) {
105 if (d_mountpoint(dentry)) {
106 dput(dentry);
107 return;
108 }
109 /*
110 * If we're generating inode numbers, then we don't
111 * want to clobber the existing one with the one that
112 * the readdir code created.
113 */
114 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM))
115 fattr->cf_uniqueid = CIFS_I(inode)->uniqueid;
116
117 /* update inode in place
118 * if both i_ino and i_mode didn't change */
119 if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid &&
120 (inode->i_mode & S_IFMT) ==
121 (fattr->cf_mode & S_IFMT)) {
122 cifs_fattr_to_inode(inode, fattr);
123 dput(dentry);
124 return;
125 }
126 }
127 d_invalidate(dentry);
128 dput(dentry);
129 goto retry;
130 } else {
131 inode = cifs_iget(sb, fattr);
132 if (!inode)
133 inode = ERR_PTR(-ENOMEM);
134 alias = d_splice_alias(inode, dentry);
135 d_lookup_done(dentry);
136 if (alias && !IS_ERR(alias))
137 dput(alias);
138 }
139 dput(dentry);
140 }
141
142 static void
cifs_fill_common_info(struct cifs_fattr * fattr,struct cifs_sb_info * cifs_sb)143 cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
144 {
145 fattr->cf_uid = cifs_sb->mnt_uid;
146 fattr->cf_gid = cifs_sb->mnt_gid;
147
148 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
149 fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
150 fattr->cf_dtype = DT_DIR;
151 } else {
152 fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
153 fattr->cf_dtype = DT_REG;
154 }
155
156 /*
157 * We need to revalidate it further to make a decision about whether it
158 * is a symbolic link, DFS referral or a reparse point with a direct
159 * access like junctions, deduplicated files, NFS symlinks.
160 */
161 if (fattr->cf_cifsattrs & ATTR_REPARSE)
162 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
163
164 /* non-unix readdir doesn't provide nlink */
165 fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
166
167 if (fattr->cf_cifsattrs & ATTR_READONLY)
168 fattr->cf_mode &= ~S_IWUGO;
169
170 /*
171 * We of course don't get ACL info in FIND_FIRST/NEXT results, so
172 * mark it for revalidation so that "ls -l" will look right. It might
173 * be super-slow, but if we don't do this then the ownership of files
174 * may look wrong since the inodes may not have timed out by the time
175 * "ls" does a stat() call on them.
176 */
177 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL)
178 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
179
180 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
181 fattr->cf_cifsattrs & ATTR_SYSTEM) {
182 if (fattr->cf_eof == 0) {
183 fattr->cf_mode &= ~S_IFMT;
184 fattr->cf_mode |= S_IFIFO;
185 fattr->cf_dtype = DT_FIFO;
186 } else {
187 /*
188 * trying to get the type and mode via SFU can be slow,
189 * so just call those regular files for now, and mark
190 * for reval
191 */
192 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
193 }
194 }
195 }
196
197 void
cifs_dir_info_to_fattr(struct cifs_fattr * fattr,FILE_DIRECTORY_INFO * info,struct cifs_sb_info * cifs_sb)198 cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
199 struct cifs_sb_info *cifs_sb)
200 {
201 memset(fattr, 0, sizeof(*fattr));
202 fattr->cf_cifsattrs = le32_to_cpu(info->ExtFileAttributes);
203 fattr->cf_eof = le64_to_cpu(info->EndOfFile);
204 fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
205 fattr->cf_createtime = le64_to_cpu(info->CreationTime);
206 fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
207 fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
208 fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
209
210 cifs_fill_common_info(fattr, cifs_sb);
211 }
212
213 static void
cifs_std_info_to_fattr(struct cifs_fattr * fattr,FIND_FILE_STANDARD_INFO * info,struct cifs_sb_info * cifs_sb)214 cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
215 struct cifs_sb_info *cifs_sb)
216 {
217 int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
218
219 memset(fattr, 0, sizeof(*fattr));
220 fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
221 info->LastAccessTime, offset);
222 fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
223 info->LastWriteTime, offset);
224 fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
225 info->LastWriteTime, offset);
226
227 fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
228 fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
229 fattr->cf_eof = le32_to_cpu(info->DataSize);
230
231 cifs_fill_common_info(fattr, cifs_sb);
232 }
233
234 /* BB eventually need to add the following helper function to
235 resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
236 we try to do FindFirst on (NTFS) directory symlinks */
237 /*
238 int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
239 unsigned int xid)
240 {
241 __u16 fid;
242 int len;
243 int oplock = 0;
244 int rc;
245 struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb);
246 char *tmpbuffer;
247
248 rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
249 OPEN_REPARSE_POINT, &fid, &oplock, NULL,
250 cifs_sb->local_nls,
251 cifs_remap(cifs_sb);
252 if (!rc) {
253 tmpbuffer = kmalloc(maxpath);
254 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
255 tmpbuffer,
256 maxpath -1,
257 fid,
258 cifs_sb->local_nls);
259 if (CIFSSMBClose(xid, ptcon, fid)) {
260 cifs_dbg(FYI, "Error closing temporary reparsepoint open\n");
261 }
262 }
263 }
264 */
265
266 static int
initiate_cifs_search(const unsigned int xid,struct file * file)267 initiate_cifs_search(const unsigned int xid, struct file *file)
268 {
269 __u16 search_flags;
270 int rc = 0;
271 char *full_path = NULL;
272 struct cifsFileInfo *cifsFile;
273 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
274 struct tcon_link *tlink = NULL;
275 struct cifs_tcon *tcon;
276 struct TCP_Server_Info *server;
277
278 if (file->private_data == NULL) {
279 tlink = cifs_sb_tlink(cifs_sb);
280 if (IS_ERR(tlink))
281 return PTR_ERR(tlink);
282
283 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
284 if (cifsFile == NULL) {
285 rc = -ENOMEM;
286 goto error_exit;
287 }
288 spin_lock_init(&cifsFile->file_info_lock);
289 file->private_data = cifsFile;
290 cifsFile->tlink = cifs_get_tlink(tlink);
291 tcon = tlink_tcon(tlink);
292 } else {
293 cifsFile = file->private_data;
294 tcon = tlink_tcon(cifsFile->tlink);
295 }
296
297 server = tcon->ses->server;
298
299 if (!server->ops->query_dir_first) {
300 rc = -ENOSYS;
301 goto error_exit;
302 }
303
304 cifsFile->invalidHandle = true;
305 cifsFile->srch_inf.endOfSearch = false;
306
307 full_path = build_path_from_dentry(file_dentry(file));
308 if (full_path == NULL) {
309 rc = -ENOMEM;
310 goto error_exit;
311 }
312
313 cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos);
314
315 ffirst_retry:
316 /* test for Unix extensions */
317 /* but now check for them on the share/mount not on the SMB session */
318 /* if (cap_unix(tcon->ses) { */
319 if (tcon->unix_ext)
320 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
321 else if ((tcon->ses->capabilities &
322 tcon->ses->server->vals->cap_nt_find) == 0) {
323 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
324 } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
325 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
326 } else /* not srvinos - BB fixme add check for backlevel? */ {
327 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
328 }
329
330 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
331 if (backup_cred(cifs_sb))
332 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
333
334 rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb,
335 &cifsFile->fid, search_flags,
336 &cifsFile->srch_inf);
337
338 if (rc == 0)
339 cifsFile->invalidHandle = false;
340 /* BB add following call to handle readdir on new NTFS symlink errors
341 else if STATUS_STOPPED_ON_SYMLINK
342 call get_symlink_reparse_path and retry with new path */
343 else if ((rc == -EOPNOTSUPP) &&
344 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
345 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
346 goto ffirst_retry;
347 }
348 error_exit:
349 kfree(full_path);
350 cifs_put_tlink(tlink);
351 return rc;
352 }
353
354 /* return length of unicode string in bytes */
cifs_unicode_bytelen(const char * str)355 static int cifs_unicode_bytelen(const char *str)
356 {
357 int len;
358 const __le16 *ustr = (const __le16 *)str;
359
360 for (len = 0; len <= PATH_MAX; len++) {
361 if (ustr[len] == 0)
362 return len << 1;
363 }
364 cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n");
365 return len << 1;
366 }
367
nxt_dir_entry(char * old_entry,char * end_of_smb,int level)368 static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
369 {
370 char *new_entry;
371 FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
372
373 if (level == SMB_FIND_FILE_INFO_STANDARD) {
374 FIND_FILE_STANDARD_INFO *pfData;
375 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
376
377 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
378 pfData->FileNameLength;
379 } else
380 new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
381 cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry);
382 /* validate that new_entry is not past end of SMB */
383 if (new_entry >= end_of_smb) {
384 cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n",
385 new_entry, end_of_smb, old_entry);
386 return NULL;
387 } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
388 (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
389 || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
390 (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb))) {
391 cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n",
392 new_entry, end_of_smb);
393 return NULL;
394 } else
395 return new_entry;
396
397 }
398
399 struct cifs_dirent {
400 const char *name;
401 size_t namelen;
402 u32 resume_key;
403 u64 ino;
404 };
405
cifs_fill_dirent_unix(struct cifs_dirent * de,const FILE_UNIX_INFO * info,bool is_unicode)406 static void cifs_fill_dirent_unix(struct cifs_dirent *de,
407 const FILE_UNIX_INFO *info, bool is_unicode)
408 {
409 de->name = &info->FileName[0];
410 if (is_unicode)
411 de->namelen = cifs_unicode_bytelen(de->name);
412 else
413 de->namelen = strnlen(de->name, PATH_MAX);
414 de->resume_key = info->ResumeKey;
415 de->ino = le64_to_cpu(info->basic.UniqueId);
416 }
417
cifs_fill_dirent_dir(struct cifs_dirent * de,const FILE_DIRECTORY_INFO * info)418 static void cifs_fill_dirent_dir(struct cifs_dirent *de,
419 const FILE_DIRECTORY_INFO *info)
420 {
421 de->name = &info->FileName[0];
422 de->namelen = le32_to_cpu(info->FileNameLength);
423 de->resume_key = info->FileIndex;
424 }
425
cifs_fill_dirent_full(struct cifs_dirent * de,const FILE_FULL_DIRECTORY_INFO * info)426 static void cifs_fill_dirent_full(struct cifs_dirent *de,
427 const FILE_FULL_DIRECTORY_INFO *info)
428 {
429 de->name = &info->FileName[0];
430 de->namelen = le32_to_cpu(info->FileNameLength);
431 de->resume_key = info->FileIndex;
432 }
433
cifs_fill_dirent_search(struct cifs_dirent * de,const SEARCH_ID_FULL_DIR_INFO * info)434 static void cifs_fill_dirent_search(struct cifs_dirent *de,
435 const SEARCH_ID_FULL_DIR_INFO *info)
436 {
437 de->name = &info->FileName[0];
438 de->namelen = le32_to_cpu(info->FileNameLength);
439 de->resume_key = info->FileIndex;
440 de->ino = le64_to_cpu(info->UniqueId);
441 }
442
cifs_fill_dirent_both(struct cifs_dirent * de,const FILE_BOTH_DIRECTORY_INFO * info)443 static void cifs_fill_dirent_both(struct cifs_dirent *de,
444 const FILE_BOTH_DIRECTORY_INFO *info)
445 {
446 de->name = &info->FileName[0];
447 de->namelen = le32_to_cpu(info->FileNameLength);
448 de->resume_key = info->FileIndex;
449 }
450
cifs_fill_dirent_std(struct cifs_dirent * de,const FIND_FILE_STANDARD_INFO * info)451 static void cifs_fill_dirent_std(struct cifs_dirent *de,
452 const FIND_FILE_STANDARD_INFO *info)
453 {
454 de->name = &info->FileName[0];
455 /* one byte length, no endianess conversion */
456 de->namelen = info->FileNameLength;
457 de->resume_key = info->ResumeKey;
458 }
459
cifs_fill_dirent(struct cifs_dirent * de,const void * info,u16 level,bool is_unicode)460 static int cifs_fill_dirent(struct cifs_dirent *de, const void *info,
461 u16 level, bool is_unicode)
462 {
463 memset(de, 0, sizeof(*de));
464
465 switch (level) {
466 case SMB_FIND_FILE_UNIX:
467 cifs_fill_dirent_unix(de, info, is_unicode);
468 break;
469 case SMB_FIND_FILE_DIRECTORY_INFO:
470 cifs_fill_dirent_dir(de, info);
471 break;
472 case SMB_FIND_FILE_FULL_DIRECTORY_INFO:
473 cifs_fill_dirent_full(de, info);
474 break;
475 case SMB_FIND_FILE_ID_FULL_DIR_INFO:
476 cifs_fill_dirent_search(de, info);
477 break;
478 case SMB_FIND_FILE_BOTH_DIRECTORY_INFO:
479 cifs_fill_dirent_both(de, info);
480 break;
481 case SMB_FIND_FILE_INFO_STANDARD:
482 cifs_fill_dirent_std(de, info);
483 break;
484 default:
485 cifs_dbg(FYI, "Unknown findfirst level %d\n", level);
486 return -EINVAL;
487 }
488
489 return 0;
490 }
491
492 #define UNICODE_DOT cpu_to_le16(0x2e)
493
494 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
cifs_entry_is_dot(struct cifs_dirent * de,bool is_unicode)495 static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode)
496 {
497 int rc = 0;
498
499 if (!de->name)
500 return 0;
501
502 if (is_unicode) {
503 __le16 *ufilename = (__le16 *)de->name;
504 if (de->namelen == 2) {
505 /* check for . */
506 if (ufilename[0] == UNICODE_DOT)
507 rc = 1;
508 } else if (de->namelen == 4) {
509 /* check for .. */
510 if (ufilename[0] == UNICODE_DOT &&
511 ufilename[1] == UNICODE_DOT)
512 rc = 2;
513 }
514 } else /* ASCII */ {
515 if (de->namelen == 1) {
516 if (de->name[0] == '.')
517 rc = 1;
518 } else if (de->namelen == 2) {
519 if (de->name[0] == '.' && de->name[1] == '.')
520 rc = 2;
521 }
522 }
523
524 return rc;
525 }
526
527 /* Check if directory that we are searching has changed so we can decide
528 whether we can use the cached search results from the previous search */
is_dir_changed(struct file * file)529 static int is_dir_changed(struct file *file)
530 {
531 struct inode *inode = file_inode(file);
532 struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
533
534 if (cifsInfo->time == 0)
535 return 1; /* directory was changed, perhaps due to unlink */
536 else
537 return 0;
538
539 }
540
cifs_save_resume_key(const char * current_entry,struct cifsFileInfo * file_info)541 static int cifs_save_resume_key(const char *current_entry,
542 struct cifsFileInfo *file_info)
543 {
544 struct cifs_dirent de;
545 int rc;
546
547 rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level,
548 file_info->srch_inf.unicode);
549 if (!rc) {
550 file_info->srch_inf.presume_name = de.name;
551 file_info->srch_inf.resume_name_len = de.namelen;
552 file_info->srch_inf.resume_key = de.resume_key;
553 }
554 return rc;
555 }
556
557 /*
558 * Find the corresponding entry in the search. Note that the SMB server returns
559 * search entries for . and .. which complicates logic here if we choose to
560 * parse for them and we do not assume that they are located in the findfirst
561 * return buffer. We start counting in the buffer with entry 2 and increment for
562 * every entry (do not increment for . or .. entry).
563 */
564 static int
find_cifs_entry(const unsigned int xid,struct cifs_tcon * tcon,loff_t pos,struct file * file,char ** current_entry,int * num_to_ret)565 find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos,
566 struct file *file, char **current_entry, int *num_to_ret)
567 {
568 __u16 search_flags;
569 int rc = 0;
570 int pos_in_buf = 0;
571 loff_t first_entry_in_buffer;
572 loff_t index_to_find = pos;
573 struct cifsFileInfo *cfile = file->private_data;
574 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
575 struct TCP_Server_Info *server = tcon->ses->server;
576 /* check if index in the buffer */
577
578 if (!server->ops->query_dir_first || !server->ops->query_dir_next)
579 return -ENOSYS;
580
581 if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL))
582 return -ENOENT;
583
584 *current_entry = NULL;
585 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry -
586 cfile->srch_inf.entries_in_buffer;
587
588 /*
589 * If first entry in buf is zero then is first buffer
590 * in search response data which means it is likely . and ..
591 * will be in this buffer, although some servers do not return
592 * . and .. for the root of a drive and for those we need
593 * to start two entries earlier.
594 */
595
596 dump_cifs_file_struct(file, "In fce ");
597 if (((index_to_find < cfile->srch_inf.index_of_last_entry) &&
598 is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) {
599 /* close and restart search */
600 cifs_dbg(FYI, "search backing up - close and restart search\n");
601 spin_lock(&cfile->file_info_lock);
602 if (server->ops->dir_needs_close(cfile)) {
603 cfile->invalidHandle = true;
604 spin_unlock(&cfile->file_info_lock);
605 if (server->ops->close_dir)
606 server->ops->close_dir(xid, tcon, &cfile->fid);
607 } else
608 spin_unlock(&cfile->file_info_lock);
609 if (cfile->srch_inf.ntwrk_buf_start) {
610 cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n");
611 if (cfile->srch_inf.smallBuf)
612 cifs_small_buf_release(cfile->srch_inf.
613 ntwrk_buf_start);
614 else
615 cifs_buf_release(cfile->srch_inf.
616 ntwrk_buf_start);
617 cfile->srch_inf.ntwrk_buf_start = NULL;
618 }
619 rc = initiate_cifs_search(xid, file);
620 if (rc) {
621 cifs_dbg(FYI, "error %d reinitiating a search on rewind\n",
622 rc);
623 return rc;
624 }
625 /* FindFirst/Next set last_entry to NULL on malformed reply */
626 if (cfile->srch_inf.last_entry)
627 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
628 }
629
630 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
631 if (backup_cred(cifs_sb))
632 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
633
634 while ((index_to_find >= cfile->srch_inf.index_of_last_entry) &&
635 (rc == 0) && !cfile->srch_inf.endOfSearch) {
636 cifs_dbg(FYI, "calling findnext2\n");
637 rc = server->ops->query_dir_next(xid, tcon, &cfile->fid,
638 search_flags,
639 &cfile->srch_inf);
640 /* FindFirst/Next set last_entry to NULL on malformed reply */
641 if (cfile->srch_inf.last_entry)
642 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
643 if (rc)
644 return -ENOENT;
645 }
646 if (index_to_find < cfile->srch_inf.index_of_last_entry) {
647 /* we found the buffer that contains the entry */
648 /* scan and find it */
649 int i;
650 char *cur_ent;
651 char *end_of_smb = cfile->srch_inf.ntwrk_buf_start +
652 server->ops->calc_smb_size(
653 cfile->srch_inf.ntwrk_buf_start);
654
655 cur_ent = cfile->srch_inf.srch_entries_start;
656 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry
657 - cfile->srch_inf.entries_in_buffer;
658 pos_in_buf = index_to_find - first_entry_in_buffer;
659 cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf);
660
661 for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) {
662 /* go entry by entry figuring out which is first */
663 cur_ent = nxt_dir_entry(cur_ent, end_of_smb,
664 cfile->srch_inf.info_level);
665 }
666 if ((cur_ent == NULL) && (i < pos_in_buf)) {
667 /* BB fixme - check if we should flag this error */
668 cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n",
669 pos_in_buf, index_to_find, rc);
670 }
671 rc = 0;
672 *current_entry = cur_ent;
673 } else {
674 cifs_dbg(FYI, "index not in buffer - could not findnext into it\n");
675 return 0;
676 }
677
678 if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) {
679 cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n");
680 *num_to_ret = 0;
681 } else
682 *num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf;
683
684 return rc;
685 }
686
cifs_filldir(char * find_entry,struct file * file,struct dir_context * ctx,char * scratch_buf,unsigned int max_len)687 static int cifs_filldir(char *find_entry, struct file *file,
688 struct dir_context *ctx,
689 char *scratch_buf, unsigned int max_len)
690 {
691 struct cifsFileInfo *file_info = file->private_data;
692 struct super_block *sb = file_inode(file)->i_sb;
693 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
694 struct cifs_dirent de = { NULL, };
695 struct cifs_fattr fattr;
696 struct qstr name;
697 int rc = 0;
698 ino_t ino;
699
700 rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,
701 file_info->srch_inf.unicode);
702 if (rc)
703 return rc;
704
705 if (de.namelen > max_len) {
706 cifs_dbg(VFS, "bad search response length %zd past smb end\n",
707 de.namelen);
708 return -EINVAL;
709 }
710
711 /* skip . and .. since we added them first */
712 if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode))
713 return 0;
714
715 if (file_info->srch_inf.unicode) {
716 struct nls_table *nlt = cifs_sb->local_nls;
717 int map_type;
718
719 map_type = cifs_remap(cifs_sb);
720 name.name = scratch_buf;
721 name.len =
722 cifs_from_utf16((char *)name.name, (__le16 *)de.name,
723 UNICODE_NAME_MAX,
724 min_t(size_t, de.namelen,
725 (size_t)max_len), nlt, map_type);
726 name.len -= nls_nullsize(nlt);
727 } else {
728 name.name = de.name;
729 name.len = de.namelen;
730 }
731
732 switch (file_info->srch_inf.info_level) {
733 case SMB_FIND_FILE_UNIX:
734 cifs_unix_basic_to_fattr(&fattr,
735 &((FILE_UNIX_INFO *)find_entry)->basic,
736 cifs_sb);
737 break;
738 case SMB_FIND_FILE_INFO_STANDARD:
739 cifs_std_info_to_fattr(&fattr,
740 (FIND_FILE_STANDARD_INFO *)find_entry,
741 cifs_sb);
742 break;
743 default:
744 cifs_dir_info_to_fattr(&fattr,
745 (FILE_DIRECTORY_INFO *)find_entry,
746 cifs_sb);
747 break;
748 }
749
750 if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
751 fattr.cf_uniqueid = de.ino;
752 } else {
753 fattr.cf_uniqueid = iunique(sb, ROOT_I);
754 cifs_autodisable_serverino(cifs_sb);
755 }
756
757 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
758 couldbe_mf_symlink(&fattr))
759 /*
760 * trying to get the type and mode can be slow,
761 * so just call those regular files for now, and mark
762 * for reval
763 */
764 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
765
766 cifs_prime_dcache(file_dentry(file), &name, &fattr);
767
768 ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
769 return !dir_emit(ctx, name.name, name.len, ino, fattr.cf_dtype);
770 }
771
772
cifs_readdir(struct file * file,struct dir_context * ctx)773 int cifs_readdir(struct file *file, struct dir_context *ctx)
774 {
775 int rc = 0;
776 unsigned int xid;
777 int i;
778 struct cifs_tcon *tcon;
779 struct cifsFileInfo *cifsFile = NULL;
780 char *current_entry;
781 int num_to_fill = 0;
782 char *tmp_buf = NULL;
783 char *end_of_smb;
784 unsigned int max_len;
785
786 xid = get_xid();
787
788 /*
789 * Ensure FindFirst doesn't fail before doing filldir() for '.' and
790 * '..'. Otherwise we won't be able to notify VFS in case of failure.
791 */
792 if (file->private_data == NULL) {
793 rc = initiate_cifs_search(xid, file);
794 cifs_dbg(FYI, "initiate cifs search rc %d\n", rc);
795 if (rc)
796 goto rddir2_exit;
797 }
798
799 if (!dir_emit_dots(file, ctx))
800 goto rddir2_exit;
801
802 /* 1) If search is active,
803 is in current search buffer?
804 if it before then restart search
805 if after then keep searching till find it */
806
807 cifsFile = file->private_data;
808 if (cifsFile->srch_inf.endOfSearch) {
809 if (cifsFile->srch_inf.emptyDir) {
810 cifs_dbg(FYI, "End of search, empty dir\n");
811 rc = 0;
812 goto rddir2_exit;
813 }
814 } /* else {
815 cifsFile->invalidHandle = true;
816 tcon->ses->server->close(xid, tcon, &cifsFile->fid);
817 } */
818
819 tcon = tlink_tcon(cifsFile->tlink);
820 rc = find_cifs_entry(xid, tcon, ctx->pos, file, ¤t_entry,
821 &num_to_fill);
822 if (rc) {
823 cifs_dbg(FYI, "fce error %d\n", rc);
824 goto rddir2_exit;
825 } else if (current_entry != NULL) {
826 cifs_dbg(FYI, "entry %lld found\n", ctx->pos);
827 } else {
828 cifs_dbg(FYI, "could not find entry\n");
829 goto rddir2_exit;
830 }
831 cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n",
832 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
833 max_len = tcon->ses->server->ops->calc_smb_size(
834 cifsFile->srch_inf.ntwrk_buf_start);
835 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
836
837 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
838 if (tmp_buf == NULL) {
839 rc = -ENOMEM;
840 goto rddir2_exit;
841 }
842
843 for (i = 0; i < num_to_fill; i++) {
844 if (current_entry == NULL) {
845 /* evaluate whether this case is an error */
846 cifs_dbg(VFS, "past SMB end, num to fill %d i %d\n",
847 num_to_fill, i);
848 break;
849 }
850 /*
851 * if buggy server returns . and .. late do we want to
852 * check for that here?
853 */
854 *tmp_buf = 0;
855 rc = cifs_filldir(current_entry, file, ctx,
856 tmp_buf, max_len);
857 if (rc) {
858 if (rc > 0)
859 rc = 0;
860 break;
861 }
862
863 ctx->pos++;
864 if (ctx->pos ==
865 cifsFile->srch_inf.index_of_last_entry) {
866 cifs_dbg(FYI, "last entry in buf at pos %lld %s\n",
867 ctx->pos, tmp_buf);
868 cifs_save_resume_key(current_entry, cifsFile);
869 break;
870 } else
871 current_entry =
872 nxt_dir_entry(current_entry, end_of_smb,
873 cifsFile->srch_inf.info_level);
874 }
875 kfree(tmp_buf);
876
877 rddir2_exit:
878 free_xid(xid);
879 return rc;
880 }
881