aboutsummaryrefslogtreecommitdiffstats
path: root/fs/cifs/dir.c
blob: 38706e8496a320a693c16f4e6be74910d8f605f5 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
/*
 *   fs/cifs/dir.c
 *
 *   vfs operations that deal with dentries
 *
 *   Copyright (C) International Business Machines  Corp., 2002,2005
 *   Author(s): Steve French (sfrench@us.ibm.com)
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/namei.h>
#include "cifsfs.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"

static void
renew_parental_timestamps(struct dentry *direntry)
{
	/* BB check if there is a way to get the kernel to do this or if we
	   really need this */
	do {
		direntry->d_time = jiffies;
		direntry = direntry->d_parent;
	} while (!IS_ROOT(direntry));
}

/* Note: caller must free return buffer */
char *
build_path_from_dentry(struct dentry *direntry)
{
	struct dentry *temp;
	int namelen;
	int pplen;
	char *full_path;
	char dirsep;

	if (direntry == NULL)
		return NULL;  /* not much we can do if dentry is freed and
		we need to reopen the file after it was closed implicitly
		when the server crashed */

	dirsep = CIFS_DIR_SEP(CIFS_SB(direntry->d_sb));
	pplen = CIFS_SB(direntry->d_sb)->prepathlen;
cifs_bp_rename_retry:
	namelen = pplen;
	for (temp = direntry; !IS_ROOT(temp);) {
		namelen += (1 + temp->d_name.len);
		temp = temp->d_parent;
		if (temp == NULL) {
			cERROR(1, ("corrupt dentry"));
			return NULL;
		}
	}

	full_path = kmalloc(namelen+1, GFP_KERNEL);
	if (full_path == NULL)
		return full_path;
	full_path[namelen] = 0;	/* trailing null */
	for (temp = direntry; !IS_ROOT(temp);) {
		namelen -= 1 + temp->d_name.len;
		if (namelen < 0) {
			break;
		} else {
			full_path[namelen] = dirsep;
			strncpy(full_path + namelen + 1, temp->d_name.name,
				temp->d_name.len);
			cFYI(0, ("name: %s", full_path + namelen));
		}
		temp = temp->d_parent;
		if (temp == NULL) {
			cERROR(1, ("corrupt dentry"));
			kfree(full_path);
			return NULL;
		}
	}
	if (namelen != pplen) {
		cERROR(1,
		       ("did not end path lookup where expected namelen is %d",
			namelen));
		/* presumably this is only possible if racing with a rename
		of one of the parent directories  (we can not lock the dentries
		above us to prevent this, but retrying should be harmless) */
		kfree(full_path);
		goto cifs_bp_rename_retry;
	}
	/* DIR_SEP already set for byte  0 / vs \ but not for
	   subsequent slashes in prepath which currently must
	   be entered the right way - not sure if there is an alternative
	   since the '\' is a valid posix character so we can not switch
	   those safely to '/' if any are found in the middle of the prepath */
	/* BB test paths to Windows with '/' in the midst of prepath */
	strncpy(full_path, CIFS_SB(direntry->d_sb)->prepath, pplen);
	return full_path;
}

/* char * build_wildcard_path_from_dentry(struct dentry *direntry)
{
	if(full_path == NULL)
		return full_path;

	full_path[namelen] = '\\';
	full_path[namelen+1] = '*';
	full_path[namelen+2] = 0;
BB remove above eight lines BB */

/* Inode operations in similar order to how they appear in Linux file fs.h */

int
cifs_create(struct inode *inode, struct dentry *direntry, int mode,
		struct nameidata *nd)
{
	int rc = -ENOENT;
	int xid;
	int oplock = 0;
	int desiredAccess = GENERIC_READ | GENERIC_WRITE;
	__u16 fileHandle;
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
	char *full_path = NULL;
	FILE_ALL_INFO *buf = NULL;
	struct inode *newinode = NULL;
	struct cifsFileInfo *pCifsFile = NULL;
	struct cifsInodeInfo *pCifsInode;
	int disposition = FILE_OVERWRITE_IF;
	int write_only = FALSE;

	xid = GetXid();

	cifs_sb = CIFS_SB(inode->i_sb);
	pTcon = cifs_sb->tcon;

	full_path = build_path_from_dentry(direntry);
	if (full_path == NULL) {
		FreeXid(xid);
		return -ENOMEM;
	}

	if (nd && (nd->flags & LOOKUP_OPEN)) {
		int oflags = nd->intent.open.flags;

		desiredAccess = 0;
		if (oflags & FMODE_READ)
			desiredAccess |= GENERIC_READ;
		if (oflags & FMODE_WRITE) {
			desiredAccess |= GENERIC_WRITE;
			if (!(oflags & FMODE_READ))
				write_only = TRUE;
		}

		if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
			disposition = FILE_CREATE;
		else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
			disposition = FILE_OVERWRITE_IF;
		else if ((oflags & O_CREAT) == O_CREAT)
			disposition = FILE_OPEN_IF;
		else {
			cFYI(1, ("Create flag not set in create function"));
		}
	}

	/* BB add processing to set equivalent of mode - e.g. via CreateX with
	   ACLs */
	if (oplockEnabled)
		oplock = REQ_OPLOCK;

	buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
	if (buf == NULL) {
		kfree(full_path);
		FreeXid(xid);
		return -ENOMEM;
	}
	if (cifs_sb->tcon->ses->capabilities & CAP_NT_SMBS)
		rc = CIFSSMBOpen(xid, pTcon, full_path, disposition,
			 desiredAccess, CREATE_NOT_DIR,
			 &fileHandle, &oplock, buf, cifs_sb->local_nls,
			 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
	else
		rc = -EIO; /* no NT SMB support fall into legacy open below */

	if (rc == -EIO) {
		/* old server, retry the open legacy style */
		rc = SMBLegacyOpen(xid, pTcon, full_path, disposition,
			desiredAccess, CREATE_NOT_DIR,
			&fileHandle, &oplock, buf, cifs_sb->local_nls,
			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
	}
	if (rc) {
		cFYI(1, ("cifs_create returned 0x%x", rc));
	} else {
		/* If Open reported that we actually created a file
		then we now have to set the mode if possible */
		if ((cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
			(oplock & CIFS_CREATE_ACTION)) {
			mode &= ~current->fs->umask;
			if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
				CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode,
					(__u64)current->fsuid,
					(__u64)current->fsgid,
					0 /* dev */,
					cifs_sb->local_nls,
					cifs_sb->mnt_cifs_flags &
						CIFS_MOUNT_MAP_SPECIAL_CHR);
			} else {
				CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode,
					(__u64)-1,
					(__u64)-1,
					0 /* dev */,
					cifs_sb->local_nls,
					cifs_sb->mnt_cifs_flags &
						CIFS_MOUNT_MAP_SPECIAL_CHR);
			}
		} else {
			/* BB implement mode setting via Windows security
			   descriptors e.g. */
			/* CIFSSMBWinSetPerms(xid,pTcon,path,mode,-1,-1,nls);*/

			/* Could set r/o dos attribute if mode & 0222 == 0 */
		}

	/* BB server might mask mode so we have to query for Unix case*/
		if (pTcon->ses->capabilities & CAP_UNIX)
			rc = cifs_get_inode_info_unix(&newinode, full_path,
						 inode->i_sb, xid);
		else {
			rc = cifs_get_inode_info(&newinode, full_path,
						 buf, inode->i_sb, xid);
			if (newinode) {
				newinode->i_mode = mode;
				if ((oplock & CIFS_CREATE_ACTION) &&
				    (cifs_sb->mnt_cifs_flags &
				     CIFS_MOUNT_SET_UID)) {
					newinode->i_uid = current->fsuid;
					newinode->i_gid = current->fsgid;
				}
			}
		}

		if (rc != 0) {
			cFYI(1,
			     ("Create worked but get_inode_info failed rc = %d",
			      rc));
		} else {
			if (pTcon->nocase)
				direntry->d_op = &cifs_ci_dentry_ops;
			else
				direntry->d_op = &cifs_dentry_ops;
			d_instantiate(direntry, newinode);
		}
		if ((nd->flags & LOOKUP_OPEN) == FALSE) {
			/* mknod case - do not leave file open */
			CIFSSMBClose(xid, pTcon, fileHandle);
		} else if (newinode) {
			pCifsFile =
			   kzalloc(sizeof (struct cifsFileInfo), GFP_KERNEL);

			if (pCifsFile == NULL)
				goto cifs_create_out;
			pCifsFile->netfid = fileHandle;
			pCifsFile->pid = current->tgid;
			pCifsFile->pInode = newinode;
			pCifsFile->invalidHandle = FALSE;
			pCifsFile->closePend     = FALSE;
			init_MUTEX(&pCifsFile->fh_sem);
			mutex_init(&pCifsFile->lock_mutex);
			INIT_LIST_HEAD(&pCifsFile->llist);
			atomic_set(&pCifsFile->wrtPending, 0);

			/* set the following in open now
				pCifsFile->pfile = file; */
			write_lock(&GlobalSMBSeslock);
			list_add(&pCifsFile->tlist, &pTcon->openFileList);
			pCifsInode = CIFS_I(newinode);
			if (pCifsInode) {
				/* if readable file instance put first in list*/
				if (write_only == TRUE) {
					list_add_tail(&pCifsFile->flist,
						&pCifsInode->openFileList);
				} else {
					list_add(&pCifsFile->flist,
						&pCifsInode->openFileList);
				}
				if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
					pCifsInode->clientCanCacheAll = TRUE;
					pCifsInode->clientCanCacheRead = TRUE;
					cFYI(1, ("Exclusive Oplock inode %p",
						newinode));
				} else if ((oplock & 0xF) == OPLOCK_READ)
					pCifsInode->clientCanCacheRead = TRUE;
			}
			write_unlock(&GlobalSMBSeslock);
		}
	}
cifs_create_out:
	kfree(buf);
	kfree(full_path);
	FreeXid(xid);
	return rc;
}

int cifs_mknod(struct inode *inode, struct dentry *direntry, int mode,
		dev_t device_number)
{
	int rc = -EPERM;
	int xid;
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
	char *full_path = NULL;
	struct inode *newinode = NULL;

	if (!old_valid_dev(device_number))
		return -EINVAL;

	xid = GetXid();

	cifs_sb = CIFS_SB(inode->i_sb);
	pTcon = cifs_sb->tcon;

	full_path = build_path_from_dentry(direntry);
	if (full_path == NULL)
		rc = -ENOMEM;
	else if (pTcon->ses->capabilities & CAP_UNIX) {
		mode &= ~current->fs->umask;
		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
			rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path,
				mode, (__u64)current->fsuid,
				(__u64)current->fsgid,
				device_number, cifs_sb->local_nls,
				cifs_sb->mnt_cifs_flags &
					CIFS_MOUNT_MAP_SPECIAL_CHR);
		} else {
			rc = CIFSSMBUnixSetPerms(xid, pTcon,
				full_path, mode, (__u64)-1, (__u64)-1,
				device_number, cifs_sb->local_nls,
				cifs_sb->mnt_cifs_flags &
					CIFS_MOUNT_MAP_SPECIAL_CHR);
		}

		if (!rc) {
			rc = cifs_get_inode_info_unix(&newinode, full_path,
						inode->i_sb, xid);
			if (pTcon->nocase)
				direntry->d_op = &cifs_ci_dentry_ops;
			else
				direntry->d_op = &cifs_dentry_ops;
			if (rc == 0)
				d_instantiate(direntry, newinode);
		}
	} else {
		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
			int oplock = 0;
			u16 fileHandle;
			FILE_ALL_INFO * buf;

			cFYI(1, ("sfu compat create special file"));

			buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
			if (buf == NULL) {
				kfree(full_path);
				FreeXid(xid);
				return -ENOMEM;
			}

			rc = CIFSSMBOpen(xid, pTcon, full_path,
					 FILE_CREATE, /* fail if exists */
					 GENERIC_WRITE /* BB would
					  WRITE_OWNER | WRITE_DAC be better? */,
					 /* Create a file and set the
					    file attribute to SYSTEM */
					 CREATE_NOT_DIR | CREATE_OPTION_SPECIAL,
					 &fileHandle, &oplock, buf,
					 cifs_sb->local_nls,
					 cifs_sb->mnt_cifs_flags &
					    CIFS_MOUNT_MAP_SPECIAL_CHR);

			/* BB FIXME - add handling for backlevel servers
			   which need legacy open and check for all
			   calls to SMBOpen for fallback to SMBLeagcyOpen */
			if (!rc) {
				/* BB Do not bother to decode buf since no
				   local inode yet to put timestamps in,
				   but we can reuse it safely */
				int bytes_written;
				struct win_dev *pdev;
				pdev = (struct win_dev *)buf;
				if (S_ISCHR(mode)) {
					memcpy(pdev->type, "IntxCHR", 8);
					pdev->major =
					      cpu_to_le64(MAJOR(device_number));
					pdev->minor =
					      cpu_to_le64(MINOR(device_number));
					rc = CIFSSMBWrite(xid, pTcon,
						fileHandle,
						sizeof(struct win_dev),
						0, &bytes_written, (char *)pdev,
						NULL, 0);
				} else if (S_ISBLK(mode)) {
					memcpy(pdev->type, "IntxBLK", 8);
					pdev->major =
					      cpu_to_le64(MAJOR(device_number));
					pdev->minor =
					      cpu_to_le64(MINOR(device_number));
					rc = CIFSSMBWrite(xid, pTcon,
						fileHandle,
						sizeof(struct win_dev),
						0, &bytes_written, (char *)pdev,
						NULL, 0);
				} /* else if(S_ISFIFO */
				CIFSSMBClose(xid, pTcon, fileHandle);
				d_drop(direntry);
			}
			kfree(buf);
			/* add code here to set EAs */
		}
	}

	kfree(full_path);
	FreeXid(xid);
	return rc;
}


struct dentry *
cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
	    struct nameidata *nd)
{
	int xid;
	int rc = 0; /* to get around spurious gcc warning, set to zero here */
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
	struct inode *newInode = NULL;
	char *full_path = NULL;

	xid = GetXid();

	cFYI(1,
	     (" parent inode = 0x%p name is: %s and dentry = 0x%p",
	      parent_dir_inode, direntry->d_name.name, direntry));

	/* check whether path exists */

	cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
	pTcon = cifs_sb->tcon;

	/*
	 * Don't allow the separator character in a path component.
	 * The VFS will not allow "/", but "\" is allowed by posix.
	 */
	if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
		int i;
		for (i = 0; i < direntry->d_name.len; i++)
			if (direntry->d_name.name[i] == '\\') {
				cFYI(1, ("Invalid file name"));
				FreeXid(xid);
				return ERR_PTR(-EINVAL);
			}
	}

	/* can not grab the rename sem here since it would
	deadlock in the cases (beginning of sys_rename itself)
	in which we already have the sb rename sem */
	full_path = build_path_from_dentry(direntry);
	if (full_path == NULL) {
		FreeXid(xid);
		return ERR_PTR(-ENOMEM);
	}

	if (direntry->d_inode != NULL) {
		cFYI(1, (" non-NULL inode in lookup"));
	} else {
		cFYI(1, (" NULL inode in lookup"));
	}
	cFYI(1,
	     (" Full path: %s inode = 0x%p", full_path, direntry->d_inode));

	if (pTcon->ses->capabilities & CAP_UNIX)
		rc = cifs_get_inode_info_unix(&newInode, full_path,
					      parent_dir_inode->i_sb, xid);
	else
		rc = cifs_get_inode_info(&newInode, full_path, NULL,
					 parent_dir_inode->i_sb, xid);

	if ((rc == 0) && (newInode != NULL)) {
		if (pTcon->nocase)
			direntry->d_op = &cifs_ci_dentry_ops;
		else
			direntry->d_op = &cifs_dentry_ops;
		d_add(direntry, newInode);

		/* since paths are not looked up by component - the parent
		   directories are presumed to be good here */
		renew_parental_timestamps(direntry);

	} else if (rc == -ENOENT) {
		rc = 0;
		direntry->d_time = jiffies;
		if (pTcon->nocase)
			direntry->d_op = &cifs_ci_dentry_ops;
		else
			direntry->d_op = &cifs_dentry_ops;
		d_add(direntry, NULL);
	/*	if it was once a directory (but how can we tell?) we could do
		shrink_dcache_parent(direntry); */
	} else {
		cERROR(1, ("Error 0x%x on cifs_get_inode_info in lookup of %s",
			   rc, full_path));
		/* BB special case check for Access Denied - watch security
		exposure of returning dir info implicitly via different rc
		if file exists or not but no access BB */
	}

	kfree(full_path);
	FreeXid(xid);
	return ERR_PTR(rc);
}

static int
cifs_d_revalidate(struct dentry *direntry, struct nameidata *nd)
{
	int isValid = 1;

	if (direntry->d_inode) {
		if (cifs_revalidate(direntry)) {
			return 0;
		}
	} else {
		cFYI(1, ("neg dentry 0x%p name = %s",
			 direntry, direntry->d_name.name));
		if (time_after(jiffies, direntry->d_time + HZ) ||
			!lookupCacheEnabled) {
			d_drop(direntry);
			isValid = 0;
		}
	}

	return isValid;
}

/* static int cifs_d_delete(struct dentry *direntry)
{
	int rc = 0;

	cFYI(1, ("In cifs d_delete, name = %s", direntry->d_name.name));

	return rc;
}     */

struct dentry_operations cifs_dentry_ops = {
	.d_revalidate = cifs_d_revalidate,
/* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
};

static int cifs_ci_hash(struct dentry *dentry, struct qstr *q)
{
	struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_sb)->local_nls;
	unsigned long hash;
	int i;

	hash = init_name_hash();
	for (i = 0; i < q->len; i++)
		hash = partial_name_hash(nls_tolower(codepage, q->name[i]),
					 hash);
	q->hash = end_name_hash(hash);

	return 0;
}

static int cifs_ci_compare(struct dentry *dentry, struct qstr *a,
			   struct qstr *b)
{
	struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_sb)->local_nls;

	if ((a->len == b->len) &&
	    (nls_strnicmp(codepage, a->name, b->name, a->len) == 0)) {
		/*
		 * To preserve case, don't let an existing negative dentry's
		 * case take precedence.  If a is not a negative dentry, this
		 * should have no side effects
		 */
		memcpy((unsigned char *)a->name, b->name, a->len);
		return 0;
	}
	return 1;
}

struct dentry_operations cifs_ci_dentry_ops = {
	.d_revalidate = cifs_d_revalidate,
	.d_hash = cifs_ci_hash,
	.d_compare = cifs_ci_compare,
};