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