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v3.5.6
  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			cFYI(1, "empty cifs private file data");
 52			return;
 53		}
 54		if (cf->invalidHandle)
 55			cFYI(1, "invalid handle");
 56		if (cf->srch_inf.endOfSearch)
 57			cFYI(1, "end of search");
 58		if (cf->srch_inf.emptyDir)
 59			cFYI(1, "empty dir");
 60	}
 61}
 62#else
 63static inline void dump_cifs_file_struct(struct file *file, char *label)
 64{
 65}
 66#endif /* DEBUG2 */
 67
 68/*
 
 
 69 * Find the dentry that matches "name". If there isn't one, create one. If it's
 70 * a negative dentry or the uniqueid changed, then drop it and recreate it.
 
 71 */
 72static struct dentry *
 73cifs_readdir_lookup(struct dentry *parent, struct qstr *name,
 74		    struct cifs_fattr *fattr)
 75{
 76	struct dentry *dentry, *alias;
 77	struct inode *inode;
 78	struct super_block *sb = parent->d_inode->i_sb;
 79
 80	cFYI(1, "For %s", name->name);
 81
 82	if (parent->d_op && parent->d_op->d_hash)
 83		parent->d_op->d_hash(parent, parent->d_inode, name);
 84	else
 85		name->hash = full_name_hash(name->name, name->len);
 86
 87	dentry = d_lookup(parent, name);
 88	if (dentry) {
 89		inode = dentry->d_inode;
 90		/* update inode in place if i_ino didn't change */
 91		if (inode && CIFS_I(inode)->uniqueid == fattr->cf_uniqueid) {
 92			cifs_fattr_to_inode(inode, fattr);
 93			return dentry;
 94		}
 95		d_drop(dentry);
 96		dput(dentry);
 97	}
 98
 99	dentry = d_alloc(parent, name);
100	if (dentry == NULL)
101		return NULL;
102
103	inode = cifs_iget(sb, fattr);
104	if (!inode) {
105		dput(dentry);
106		return NULL;
 
 
 
 
 
 
 
 
107	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
108
109	alias = d_materialise_unique(dentry, inode);
110	if (alias != NULL) {
 
 
 
 
 
 
 
 
 
111		dput(dentry);
112		if (IS_ERR(alias))
113			return NULL;
114		dentry = alias;
 
 
 
 
 
 
115	}
116
117	return dentry;
118}
119
120static void
121cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
122{
123	fattr->cf_uid = cifs_sb->mnt_uid;
124	fattr->cf_gid = cifs_sb->mnt_gid;
125
126	if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
127		fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
128		fattr->cf_dtype = DT_DIR;
129	} else {
130		fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
131		fattr->cf_dtype = DT_REG;
132	}
133
 
 
 
 
 
 
 
 
 
 
 
134	if (fattr->cf_cifsattrs & ATTR_READONLY)
135		fattr->cf_mode &= ~S_IWUGO;
136
 
 
 
 
 
 
 
 
 
 
137	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
138	    fattr->cf_cifsattrs & ATTR_SYSTEM) {
139		if (fattr->cf_eof == 0)  {
140			fattr->cf_mode &= ~S_IFMT;
141			fattr->cf_mode |= S_IFIFO;
142			fattr->cf_dtype = DT_FIFO;
143		} else {
144			/*
145			 * trying to get the type and mode via SFU can be slow,
146			 * so just call those regular files for now, and mark
147			 * for reval
148			 */
149			fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
150		}
151	}
152}
153
154static void
155cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
156		       struct cifs_sb_info *cifs_sb)
157{
158	memset(fattr, 0, sizeof(*fattr));
159	fattr->cf_cifsattrs = le32_to_cpu(info->ExtFileAttributes);
160	fattr->cf_eof = le64_to_cpu(info->EndOfFile);
161	fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
162	fattr->cf_createtime = le64_to_cpu(info->CreationTime);
163	fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
164	fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
165	fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
166
167	cifs_fill_common_info(fattr, cifs_sb);
168}
169
170static void
171cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
172		       struct cifs_sb_info *cifs_sb)
173{
174	int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
175
176	memset(fattr, 0, sizeof(*fattr));
177	fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
178					    info->LastAccessTime, offset);
179	fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
180					    info->LastWriteTime, offset);
181	fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
182					    info->LastWriteTime, offset);
183
184	fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
185	fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
186	fattr->cf_eof = le32_to_cpu(info->DataSize);
187
188	cifs_fill_common_info(fattr, cifs_sb);
189}
190
191/* BB eventually need to add the following helper function to
192      resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
193      we try to do FindFirst on (NTFS) directory symlinks */
194/*
195int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
196			     int xid)
197{
198	__u16 fid;
199	int len;
200	int oplock = 0;
201	int rc;
202	struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb);
203	char *tmpbuffer;
204
205	rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
206			OPEN_REPARSE_POINT, &fid, &oplock, NULL,
207			cifs_sb->local_nls,
208			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
209	if (!rc) {
210		tmpbuffer = kmalloc(maxpath);
211		rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
212				tmpbuffer,
213				maxpath -1,
214				fid,
215				cifs_sb->local_nls);
216		if (CIFSSMBClose(xid, ptcon, fid)) {
217			cFYI(1, "Error closing temporary reparsepoint open");
218		}
219	}
220}
221 */
222
223static int initiate_cifs_search(const int xid, struct file *file)
 
224{
225	__u16 search_flags;
226	int rc = 0;
227	char *full_path = NULL;
228	struct cifsFileInfo *cifsFile;
229	struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
230	struct tcon_link *tlink = NULL;
231	struct cifs_tcon *pTcon;
 
232
233	if (file->private_data == NULL) {
234		tlink = cifs_sb_tlink(cifs_sb);
235		if (IS_ERR(tlink))
236			return PTR_ERR(tlink);
237
238		cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
239		if (cifsFile == NULL) {
240			rc = -ENOMEM;
241			goto error_exit;
242		}
 
243		file->private_data = cifsFile;
244		cifsFile->tlink = cifs_get_tlink(tlink);
245		pTcon = tlink_tcon(tlink);
246	} else {
247		cifsFile = file->private_data;
248		pTcon = tlink_tcon(cifsFile->tlink);
 
 
 
 
 
 
 
249	}
250
251	cifsFile->invalidHandle = true;
252	cifsFile->srch_inf.endOfSearch = false;
253
254	full_path = build_path_from_dentry(file->f_path.dentry);
255	if (full_path == NULL) {
256		rc = -ENOMEM;
257		goto error_exit;
258	}
259
260	cFYI(1, "Full path: %s start at: %lld", full_path, file->f_pos);
261
262ffirst_retry:
263	/* test for Unix extensions */
264	/* but now check for them on the share/mount not on the SMB session */
265/*	if (pTcon->ses->capabilities & CAP_UNIX) { */
266	if (pTcon->unix_ext)
267		cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
268	else if ((pTcon->ses->capabilities &
269			(CAP_NT_SMBS | CAP_NT_FIND)) == 0) {
270		cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
271	} else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
272		cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
273	} else /* not srvinos - BB fixme add check for backlevel? */ {
274		cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
275	}
276
277	search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
278	if (backup_cred(cifs_sb))
279		search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
280
281	rc = CIFSFindFirst(xid, pTcon, full_path, cifs_sb->local_nls,
282		&cifsFile->netfid, search_flags, &cifsFile->srch_inf,
283		cifs_sb->mnt_cifs_flags &
284			CIFS_MOUNT_MAP_SPECIAL_CHR, CIFS_DIR_SEP(cifs_sb));
285	if (rc == 0)
286		cifsFile->invalidHandle = false;
287	/* BB add following call to handle readdir on new NTFS symlink errors
288	else if STATUS_STOPPED_ON_SYMLINK
289		call get_symlink_reparse_path and retry with new path */
290	else if ((rc == -EOPNOTSUPP) &&
291		(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
292		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
293		goto ffirst_retry;
294	}
295error_exit:
296	kfree(full_path);
297	cifs_put_tlink(tlink);
298	return rc;
299}
300
301/* return length of unicode string in bytes */
302static int cifs_unicode_bytelen(const char *str)
303{
304	int len;
305	const __le16 *ustr = (const __le16 *)str;
306
307	for (len = 0; len <= PATH_MAX; len++) {
308		if (ustr[len] == 0)
309			return len << 1;
310	}
311	cFYI(1, "Unicode string longer than PATH_MAX found");
312	return len << 1;
313}
314
315static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
316{
317	char *new_entry;
318	FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
319
320	if (level == SMB_FIND_FILE_INFO_STANDARD) {
321		FIND_FILE_STANDARD_INFO *pfData;
322		pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
323
324		new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
325				pfData->FileNameLength;
326	} else
327		new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
328	cFYI(1, "new entry %p old entry %p", new_entry, old_entry);
329	/* validate that new_entry is not past end of SMB */
330	if (new_entry >= end_of_smb) {
331		cERROR(1, "search entry %p began after end of SMB %p old entry %p",
332			new_entry, end_of_smb, old_entry);
333		return NULL;
334	} else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
335		    (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
336		  || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
337		   (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb)))  {
338		cERROR(1, "search entry %p extends after end of SMB %p",
339			new_entry, end_of_smb);
340		return NULL;
341	} else
342		return new_entry;
343
344}
345
346struct cifs_dirent {
347	const char	*name;
348	size_t		namelen;
349	u32		resume_key;
350	u64		ino;
351};
352
353static void cifs_fill_dirent_unix(struct cifs_dirent *de,
354		const FILE_UNIX_INFO *info, bool is_unicode)
355{
356	de->name = &info->FileName[0];
357	if (is_unicode)
358		de->namelen = cifs_unicode_bytelen(de->name);
359	else
360		de->namelen = strnlen(de->name, PATH_MAX);
361	de->resume_key = info->ResumeKey;
362	de->ino = le64_to_cpu(info->basic.UniqueId);
363}
364
365static void cifs_fill_dirent_dir(struct cifs_dirent *de,
366		const FILE_DIRECTORY_INFO *info)
367{
368	de->name = &info->FileName[0];
369	de->namelen = le32_to_cpu(info->FileNameLength);
370	de->resume_key = info->FileIndex;
371}
372
373static void cifs_fill_dirent_full(struct cifs_dirent *de,
374		const FILE_FULL_DIRECTORY_INFO *info)
375{
376	de->name = &info->FileName[0];
377	de->namelen = le32_to_cpu(info->FileNameLength);
378	de->resume_key = info->FileIndex;
379}
380
381static void cifs_fill_dirent_search(struct cifs_dirent *de,
382		const SEARCH_ID_FULL_DIR_INFO *info)
383{
384	de->name = &info->FileName[0];
385	de->namelen = le32_to_cpu(info->FileNameLength);
386	de->resume_key = info->FileIndex;
387	de->ino = le64_to_cpu(info->UniqueId);
388}
389
390static void cifs_fill_dirent_both(struct cifs_dirent *de,
391		const FILE_BOTH_DIRECTORY_INFO *info)
392{
393	de->name = &info->FileName[0];
394	de->namelen = le32_to_cpu(info->FileNameLength);
395	de->resume_key = info->FileIndex;
396}
397
398static void cifs_fill_dirent_std(struct cifs_dirent *de,
399		const FIND_FILE_STANDARD_INFO *info)
400{
401	de->name = &info->FileName[0];
402	/* one byte length, no endianess conversion */
403	de->namelen = info->FileNameLength;
404	de->resume_key = info->ResumeKey;
405}
406
407static int cifs_fill_dirent(struct cifs_dirent *de, const void *info,
408		u16 level, bool is_unicode)
409{
410	memset(de, 0, sizeof(*de));
411
412	switch (level) {
413	case SMB_FIND_FILE_UNIX:
414		cifs_fill_dirent_unix(de, info, is_unicode);
415		break;
416	case SMB_FIND_FILE_DIRECTORY_INFO:
417		cifs_fill_dirent_dir(de, info);
418		break;
419	case SMB_FIND_FILE_FULL_DIRECTORY_INFO:
420		cifs_fill_dirent_full(de, info);
421		break;
422	case SMB_FIND_FILE_ID_FULL_DIR_INFO:
423		cifs_fill_dirent_search(de, info);
424		break;
425	case SMB_FIND_FILE_BOTH_DIRECTORY_INFO:
426		cifs_fill_dirent_both(de, info);
427		break;
428	case SMB_FIND_FILE_INFO_STANDARD:
429		cifs_fill_dirent_std(de, info);
430		break;
431	default:
432		cFYI(1, "Unknown findfirst level %d", level);
433		return -EINVAL;
434	}
435
436	return 0;
437}
438
439#define UNICODE_DOT cpu_to_le16(0x2e)
440
441/* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
442static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode)
443{
444	int rc = 0;
445
446	if (!de->name)
447		return 0;
448
449	if (is_unicode) {
450		__le16 *ufilename = (__le16 *)de->name;
451		if (de->namelen == 2) {
452			/* check for . */
453			if (ufilename[0] == UNICODE_DOT)
454				rc = 1;
455		} else if (de->namelen == 4) {
456			/* check for .. */
457			if (ufilename[0] == UNICODE_DOT &&
458			    ufilename[1] == UNICODE_DOT)
459				rc = 2;
460		}
461	} else /* ASCII */ {
462		if (de->namelen == 1) {
463			if (de->name[0] == '.')
464				rc = 1;
465		} else if (de->namelen == 2) {
466			if (de->name[0] == '.' && de->name[1] == '.')
467				rc = 2;
468		}
469	}
470
471	return rc;
472}
473
474/* Check if directory that we are searching has changed so we can decide
475   whether we can use the cached search results from the previous search */
476static int is_dir_changed(struct file *file)
477{
478	struct inode *inode = file->f_path.dentry->d_inode;
479	struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
480
481	if (cifsInfo->time == 0)
482		return 1; /* directory was changed, perhaps due to unlink */
483	else
484		return 0;
485
486}
487
488static int cifs_save_resume_key(const char *current_entry,
489	struct cifsFileInfo *file_info)
490{
491	struct cifs_dirent de;
492	int rc;
493
494	rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level,
495			      file_info->srch_inf.unicode);
496	if (!rc) {
497		file_info->srch_inf.presume_name = de.name;
498		file_info->srch_inf.resume_name_len = de.namelen;
499		file_info->srch_inf.resume_key = de.resume_key;
500	}
501	return rc;
502}
503
504/* find the corresponding entry in the search */
505/* Note that the SMB server returns search entries for . and .. which
506   complicates logic here if we choose to parse for them and we do not
507   assume that they are located in the findfirst return buffer.*/
508/* We start counting in the buffer with entry 2 and increment for every
509   entry (do not increment for . or .. entry) */
510static int find_cifs_entry(const int xid, struct cifs_tcon *pTcon,
511	struct file *file, char **ppCurrentEntry, int *num_to_ret)
 
 
512{
513	__u16 search_flags;
514	int rc = 0;
515	int pos_in_buf = 0;
516	loff_t first_entry_in_buffer;
517	loff_t index_to_find = file->f_pos;
518	struct cifsFileInfo *cifsFile = file->private_data;
519	struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 
520	/* check if index in the buffer */
521
522	if ((cifsFile == NULL) || (ppCurrentEntry == NULL) ||
523	   (num_to_ret == NULL))
 
 
524		return -ENOENT;
525
526	*ppCurrentEntry = NULL;
527	first_entry_in_buffer =
528		cifsFile->srch_inf.index_of_last_entry -
529			cifsFile->srch_inf.entries_in_buffer;
530
531	/* if first entry in buf is zero then is first buffer
532	in search response data which means it is likely . and ..
533	will be in this buffer, although some servers do not return
534	. and .. for the root of a drive and for those we need
535	to start two entries earlier */
 
536
537	dump_cifs_file_struct(file, "In fce ");
538	if (((index_to_find < cifsFile->srch_inf.index_of_last_entry) &&
539	     is_dir_changed(file)) ||
540	   (index_to_find < first_entry_in_buffer)) {
541		/* close and restart search */
542		cFYI(1, "search backing up - close and restart search");
543		spin_lock(&cifs_file_list_lock);
544		if (!cifsFile->srch_inf.endOfSearch &&
545		    !cifsFile->invalidHandle) {
546			cifsFile->invalidHandle = true;
547			spin_unlock(&cifs_file_list_lock);
548			CIFSFindClose(xid, pTcon, cifsFile->netfid);
549		} else
550			spin_unlock(&cifs_file_list_lock);
551		if (cifsFile->srch_inf.ntwrk_buf_start) {
552			cFYI(1, "freeing SMB ff cache buf on search rewind");
553			if (cifsFile->srch_inf.smallBuf)
554				cifs_small_buf_release(cifsFile->srch_inf.
555						ntwrk_buf_start);
556			else
557				cifs_buf_release(cifsFile->srch_inf.
558						ntwrk_buf_start);
559			cifsFile->srch_inf.ntwrk_buf_start = NULL;
560		}
561		rc = initiate_cifs_search(xid, file);
562		if (rc) {
563			cFYI(1, "error %d reinitiating a search on rewind",
564				 rc);
565			return rc;
566		}
567		/* FindFirst/Next set last_entry to NULL on malformed reply */
568		if (cifsFile->srch_inf.last_entry)
569			cifs_save_resume_key(cifsFile->srch_inf.last_entry,
570						cifsFile);
571	}
572
573	search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
574	if (backup_cred(cifs_sb))
575		search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
576
577	while ((index_to_find >= cifsFile->srch_inf.index_of_last_entry) &&
578	      (rc == 0) && !cifsFile->srch_inf.endOfSearch) {
579		cFYI(1, "calling findnext2");
580		rc = CIFSFindNext(xid, pTcon, cifsFile->netfid, search_flags,
581				  &cifsFile->srch_inf);
 
582		/* FindFirst/Next set last_entry to NULL on malformed reply */
583		if (cifsFile->srch_inf.last_entry)
584			cifs_save_resume_key(cifsFile->srch_inf.last_entry,
585						cifsFile);
586		if (rc)
587			return -ENOENT;
588	}
589	if (index_to_find < cifsFile->srch_inf.index_of_last_entry) {
590		/* we found the buffer that contains the entry */
591		/* scan and find it */
592		int i;
593		char *current_entry;
594		char *end_of_smb = cifsFile->srch_inf.ntwrk_buf_start +
595			smbCalcSize((struct smb_hdr *)
596				cifsFile->srch_inf.ntwrk_buf_start);
597
598		current_entry = cifsFile->srch_inf.srch_entries_start;
599		first_entry_in_buffer = cifsFile->srch_inf.index_of_last_entry
600					- cifsFile->srch_inf.entries_in_buffer;
601		pos_in_buf = index_to_find - first_entry_in_buffer;
602		cFYI(1, "found entry - pos_in_buf %d", pos_in_buf);
603
604		for (i = 0; (i < (pos_in_buf)) && (current_entry != NULL); i++) {
605			/* go entry by entry figuring out which is first */
606			current_entry = nxt_dir_entry(current_entry, end_of_smb,
607						cifsFile->srch_inf.info_level);
608		}
609		if ((current_entry == NULL) && (i < pos_in_buf)) {
610			/* BB fixme - check if we should flag this error */
611			cERROR(1, "reached end of buf searching for pos in buf"
612			  " %d index to find %lld rc %d",
613			  pos_in_buf, index_to_find, rc);
614		}
615		rc = 0;
616		*ppCurrentEntry = current_entry;
617	} else {
618		cFYI(1, "index not in buffer - could not findnext into it");
619		return 0;
620	}
621
622	if (pos_in_buf >= cifsFile->srch_inf.entries_in_buffer) {
623		cFYI(1, "can not return entries pos_in_buf beyond last");
624		*num_to_ret = 0;
625	} else
626		*num_to_ret = cifsFile->srch_inf.entries_in_buffer - pos_in_buf;
627
628	return rc;
629}
630
631static int cifs_filldir(char *find_entry, struct file *file, filldir_t filldir,
632		void *dirent, char *scratch_buf, unsigned int max_len)
 
633{
634	struct cifsFileInfo *file_info = file->private_data;
635	struct super_block *sb = file->f_path.dentry->d_sb;
636	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
637	struct cifs_dirent de = { NULL, };
638	struct cifs_fattr fattr;
639	struct dentry *dentry;
640	struct qstr name;
641	int rc = 0;
642	ino_t ino;
643
644	rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,
645			      file_info->srch_inf.unicode);
646	if (rc)
647		return rc;
648
649	if (de.namelen > max_len) {
650		cERROR(1, "bad search response length %zd past smb end",
651			  de.namelen);
652		return -EINVAL;
653	}
654
655	/* skip . and .. since we added them first */
656	if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode))
657		return 0;
658
659	if (file_info->srch_inf.unicode) {
660		struct nls_table *nlt = cifs_sb->local_nls;
 
661
 
662		name.name = scratch_buf;
663		name.len =
664			cifs_from_utf16((char *)name.name, (__le16 *)de.name,
665					UNICODE_NAME_MAX,
666					min_t(size_t, de.namelen,
667					      (size_t)max_len), nlt,
668					cifs_sb->mnt_cifs_flags &
669						CIFS_MOUNT_MAP_SPECIAL_CHR);
670		name.len -= nls_nullsize(nlt);
671	} else {
672		name.name = de.name;
673		name.len = de.namelen;
674	}
675
676	switch (file_info->srch_inf.info_level) {
677	case SMB_FIND_FILE_UNIX:
678		cifs_unix_basic_to_fattr(&fattr,
679					 &((FILE_UNIX_INFO *)find_entry)->basic,
680					 cifs_sb);
681		break;
682	case SMB_FIND_FILE_INFO_STANDARD:
683		cifs_std_info_to_fattr(&fattr,
684				       (FIND_FILE_STANDARD_INFO *)find_entry,
685				       cifs_sb);
686		break;
687	default:
688		cifs_dir_info_to_fattr(&fattr,
689				       (FILE_DIRECTORY_INFO *)find_entry,
690				       cifs_sb);
691		break;
692	}
693
694	if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
695		fattr.cf_uniqueid = de.ino;
696	} else {
697		fattr.cf_uniqueid = iunique(sb, ROOT_I);
698		cifs_autodisable_serverino(cifs_sb);
699	}
700
701	if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
702	    CIFSCouldBeMFSymlink(&fattr))
703		/*
704		 * trying to get the type and mode can be slow,
705		 * so just call those regular files for now, and mark
706		 * for reval
707		 */
708		fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
709
710	ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
711	dentry = cifs_readdir_lookup(file->f_dentry, &name, &fattr);
712
713	rc = filldir(dirent, name.name, name.len, file->f_pos, ino,
714		     fattr.cf_dtype);
715
716	dput(dentry);
717	return rc;
718}
719
720
721int cifs_readdir(struct file *file, void *direntry, filldir_t filldir)
722{
723	int rc = 0;
724	int xid, i;
725	struct cifs_tcon *pTcon;
 
726	struct cifsFileInfo *cifsFile = NULL;
727	char *current_entry;
728	int num_to_fill = 0;
729	char *tmp_buf = NULL;
730	char *end_of_smb;
731	unsigned int max_len;
732
733	xid = GetXid();
734
735	/*
736	 * Ensure FindFirst doesn't fail before doing filldir() for '.' and
737	 * '..'. Otherwise we won't be able to notify VFS in case of failure.
738	 */
739	if (file->private_data == NULL) {
740		rc = initiate_cifs_search(xid, file);
741		cFYI(1, "initiate cifs search rc %d", rc);
742		if (rc)
743			goto rddir2_exit;
744	}
745
746	switch ((int) file->f_pos) {
747	case 0:
748		if (filldir(direntry, ".", 1, file->f_pos,
749		     file->f_path.dentry->d_inode->i_ino, DT_DIR) < 0) {
750			cERROR(1, "Filldir for current dir failed");
751			rc = -ENOMEM;
752			break;
753		}
754		file->f_pos++;
755	case 1:
756		if (filldir(direntry, "..", 2, file->f_pos,
757		     parent_ino(file->f_path.dentry), DT_DIR) < 0) {
758			cERROR(1, "Filldir for parent dir failed");
759			rc = -ENOMEM;
760			break;
761		}
762		file->f_pos++;
763	default:
764		/* 1) If search is active,
765			is in current search buffer?
766			if it before then restart search
767			if after then keep searching till find it */
768
769		if (file->private_data == NULL) {
770			rc = -EINVAL;
771			FreeXid(xid);
772			return rc;
773		}
774		cifsFile = file->private_data;
775		if (cifsFile->srch_inf.endOfSearch) {
776			if (cifsFile->srch_inf.emptyDir) {
777				cFYI(1, "End of search, empty dir");
778				rc = 0;
779				break;
780			}
781		} /* else {
782			cifsFile->invalidHandle = true;
783			CIFSFindClose(xid, pTcon, cifsFile->netfid);
784		} */
785
786		pTcon = tlink_tcon(cifsFile->tlink);
787		rc = find_cifs_entry(xid, pTcon, file,
788				&current_entry, &num_to_fill);
789		if (rc) {
790			cFYI(1, "fce error %d", rc);
791			goto rddir2_exit;
792		} else if (current_entry != NULL) {
793			cFYI(1, "entry %lld found", file->f_pos);
794		} else {
795			cFYI(1, "could not find entry");
796			goto rddir2_exit;
797		}
798		cFYI(1, "loop through %d times filling dir for net buf %p",
799			num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
800		max_len = smbCalcSize((struct smb_hdr *)
801				cifsFile->srch_inf.ntwrk_buf_start);
802		end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
803
804		tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
805		if (tmp_buf == NULL) {
806			rc = -ENOMEM;
 
 
 
 
 
 
 
 
807			break;
808		}
809
810		for (i = 0; (i < num_to_fill) && (rc == 0); i++) {
811			if (current_entry == NULL) {
812				/* evaluate whether this case is an error */
813				cERROR(1, "past SMB end,  num to fill %d i %d",
814					  num_to_fill, i);
815				break;
816			}
817			/* if buggy server returns . and .. late do
818			we want to check for that here? */
819			rc = cifs_filldir(current_entry, file,
820					filldir, direntry, tmp_buf, max_len);
821			if (rc == -EOVERFLOW) {
822				rc = 0;
823				break;
824			}
825
826			file->f_pos++;
827			if (file->f_pos ==
828				cifsFile->srch_inf.index_of_last_entry) {
829				cFYI(1, "last entry in buf at pos %lld %s",
830					file->f_pos, tmp_buf);
831				cifs_save_resume_key(current_entry, cifsFile);
832				break;
833			} else
834				current_entry =
835					nxt_dir_entry(current_entry, end_of_smb,
836						cifsFile->srch_inf.info_level);
837		}
838		kfree(tmp_buf);
839		break;
840	} /* end switch */
 
 
 
 
 
 
 
 
 
 
 
841
842rddir2_exit:
843	FreeXid(xid);
844	return rc;
845}
v4.10.11
  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 = 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;
 97retry:
 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
142static void
143cifs_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
197void
198cifs_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
213static void
214cifs_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/*
238int 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
266static int
267initiate_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
315ffirst_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	}
348error_exit:
349	kfree(full_path);
350	cifs_put_tlink(tlink);
351	return rc;
352}
353
354/* return length of unicode string in bytes */
355static 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
368static 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
399struct cifs_dirent {
400	const char	*name;
401	size_t		namelen;
402	u32		resume_key;
403	u64		ino;
404};
405
406static 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
418static 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
426static 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
434static 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
443static 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
451static 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
460static 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) */
495static 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 */
529static 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
541static 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 */
564static int
565find_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
687static 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
773int 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, &current_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
877rddir2_exit:
878	free_xid(xid);
879	return rc;
880}