Linux Audio

Check our new training course

Loading...
v3.15
  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, &current_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}
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}