aboutsummaryrefslogtreecommitdiff
path: root/fs/cifs/misc.c
blob: f2a026073b62b683cd1ca4facf40c7f338b2e7a8 (plain)
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
/*
 *   fs/cifs/misc.c
 *
 *   Copyright (C) International Business Machines  Corp., 2002,2004
 *   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/slab.h>
#include <linux/ctype.h>
#include <linux/mempool.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "smberr.h"
#include "nterr.h"

extern mempool_t *cifs_sm_req_poolp;
extern mempool_t *cifs_req_poolp;
extern struct task_struct * oplockThread;

static __u16 GlobalMid;		/* multiplex id - rotating counter */

/* The xid serves as a useful identifier for each incoming vfs request, 
   in a similar way to the mid which is useful to track each sent smb, 
   and CurrentXid can also provide a running counter (although it 
   will eventually wrap past zero) of the total vfs operations handled 
   since the cifs fs was mounted */

unsigned int
_GetXid(void)
{
	unsigned int xid;

	spin_lock(&GlobalMid_Lock);
	GlobalTotalActiveXid++;
	if (GlobalTotalActiveXid > GlobalMaxActiveXid)
		GlobalMaxActiveXid = GlobalTotalActiveXid;	/* keep high water mark for number of simultaneous vfs ops in our filesystem */
	xid = GlobalCurrentXid++;
	spin_unlock(&GlobalMid_Lock);
	return xid;
}

void
_FreeXid(unsigned int xid)
{
	spin_lock(&GlobalMid_Lock);
	/* if(GlobalTotalActiveXid == 0)
		BUG(); */
	GlobalTotalActiveXid--;
	spin_unlock(&GlobalMid_Lock);
}

struct cifsSesInfo *
sesInfoAlloc(void)
{
	struct cifsSesInfo *ret_buf;

	ret_buf =
	    (struct cifsSesInfo *) kmalloc(sizeof (struct cifsSesInfo),
					   GFP_KERNEL);
	if (ret_buf) {
		memset(ret_buf, 0, sizeof (struct cifsSesInfo));
		write_lock(&GlobalSMBSeslock);
		atomic_inc(&sesInfoAllocCount);
		ret_buf->status = CifsNew;
		list_add(&ret_buf->cifsSessionList, &GlobalSMBSessionList);
		init_MUTEX(&ret_buf->sesSem);
		write_unlock(&GlobalSMBSeslock);
	}
	return ret_buf;
}

void
sesInfoFree(struct cifsSesInfo *buf_to_free)
{
	if (buf_to_free == NULL) {
		cFYI(1, ("Null buffer passed to sesInfoFree"));
		return;
	}

	write_lock(&GlobalSMBSeslock);
	atomic_dec(&sesInfoAllocCount);
	list_del(&buf_to_free->cifsSessionList);
	write_unlock(&GlobalSMBSeslock);
	if (buf_to_free->serverOS)
		kfree(buf_to_free->serverOS);
	if (buf_to_free->serverDomain)
		kfree(buf_to_free->serverDomain);
	if (buf_to_free->serverNOS)
		kfree(buf_to_free->serverNOS);
	if (buf_to_free->password)
		kfree(buf_to_free->password);
	kfree(buf_to_free);
}

struct cifsTconInfo *
tconInfoAlloc(void)
{
	struct cifsTconInfo *ret_buf;
	ret_buf =
	    (struct cifsTconInfo *) kmalloc(sizeof (struct cifsTconInfo),
					    GFP_KERNEL);
	if (ret_buf) {
		memset(ret_buf, 0, sizeof (struct cifsTconInfo));
		write_lock(&GlobalSMBSeslock);
		atomic_inc(&tconInfoAllocCount);
		list_add(&ret_buf->cifsConnectionList,
			 &GlobalTreeConnectionList);
		ret_buf->tidStatus = CifsNew;
		INIT_LIST_HEAD(&ret_buf->openFileList);
		init_MUTEX(&ret_buf->tconSem);
#ifdef CONFIG_CIFS_STATS
		spin_lock_init(&ret_buf->stat_lock);
#endif
		write_unlock(&GlobalSMBSeslock);
	}
	return ret_buf;
}

void
tconInfoFree(struct cifsTconInfo *buf_to_free)
{
	if (buf_to_free == NULL) {
		cFYI(1, ("Null buffer passed to tconInfoFree"));
		return;
	}
	write_lock(&GlobalSMBSeslock);
	atomic_dec(&tconInfoAllocCount);
	list_del(&buf_to_free->cifsConnectionList);
	write_unlock(&GlobalSMBSeslock);
	if (buf_to_free->nativeFileSystem)
		kfree(buf_to_free->nativeFileSystem);
	kfree(buf_to_free);
}

struct smb_hdr *
cifs_buf_get(void)
{
	struct smb_hdr *ret_buf = NULL;

/* We could use negotiated size instead of max_msgsize - 
   but it may be more efficient to always alloc same size 
   albeit slightly larger than necessary and maxbuffersize 
   defaults to this and can not be bigger */
	ret_buf =
	    (struct smb_hdr *) mempool_alloc(cifs_req_poolp, SLAB_KERNEL | SLAB_NOFS);

	/* clear the first few header bytes */
	/* for most paths, more is cleared in header_assemble */
	if (ret_buf) {
		memset(ret_buf, 0, sizeof(struct smb_hdr) + 3);
		atomic_inc(&bufAllocCount);
	}

	return ret_buf;
}

void
cifs_buf_release(void *buf_to_free)
{

	if (buf_to_free == NULL) {
		/* cFYI(1, ("Null buffer passed to cifs_buf_release"));*/
		return;
	}
	mempool_free(buf_to_free,cifs_req_poolp);

	atomic_dec(&bufAllocCount);
	return;
}

struct smb_hdr *
cifs_small_buf_get(void)
{
	struct smb_hdr *ret_buf = NULL;

/* We could use negotiated size instead of max_msgsize - 
   but it may be more efficient to always alloc same size 
   albeit slightly larger than necessary and maxbuffersize 
   defaults to this and can not be bigger */
	ret_buf =
	    (struct smb_hdr *) mempool_alloc(cifs_sm_req_poolp, SLAB_KERNEL | SLAB_NOFS);
	if (ret_buf) {
	/* No need to clear memory here, cleared in header assemble */
	/*	memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
		atomic_inc(&smBufAllocCount);
	}
	return ret_buf;
}

void
cifs_small_buf_release(void *buf_to_free)
{

	if (buf_to_free == NULL) {
		cFYI(1, ("Null buffer passed to cifs_small_buf_release"));
		return;
	}
	mempool_free(buf_to_free,cifs_sm_req_poolp);

	atomic_dec(&smBufAllocCount);
	return;
}

void
header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
		const struct cifsTconInfo *treeCon, int word_count
		/* length of fixed section (word count) in two byte units  */)
{
	struct list_head* temp_item;
	struct cifsSesInfo * ses;
	char *temp = (char *) buffer;

	memset(temp,0,MAX_CIFS_HDR_SIZE);

	buffer->smb_buf_length =
	    (2 * word_count) + sizeof (struct smb_hdr) -
	    4 /*  RFC 1001 length field does not count */  +
	    2 /* for bcc field itself */ ;
	/* Note that this is the only network field that has to be converted to big endian and it is done just before we send it */

	buffer->Protocol[0] = 0xFF;
	buffer->Protocol[1] = 'S';
	buffer->Protocol[2] = 'M';
	buffer->Protocol[3] = 'B';
	buffer->Command = smb_command;
	buffer->Flags = 0x00;	/* case sensitive */
	buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
	buffer->Pid = cpu_to_le16((__u16)current->tgid);
	buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
	spin_lock(&GlobalMid_Lock);
	GlobalMid++;
	buffer->Mid = GlobalMid;
	spin_unlock(&GlobalMid_Lock);
	if (treeCon) {
		buffer->Tid = treeCon->tid;
		if (treeCon->ses) {
			if (treeCon->ses->capabilities & CAP_UNICODE)
				buffer->Flags2 |= SMBFLG2_UNICODE;
			if (treeCon->ses->capabilities & CAP_STATUS32) {
				buffer->Flags2 |= SMBFLG2_ERR_STATUS;
			}

			buffer->Uid = treeCon->ses->Suid;	/* always in LE format */
			if(multiuser_mount != 0) {
		/* For the multiuser case, there are few obvious technically  */
		/* possible mechanisms to match the local linux user (uid)    */
		/* to a valid remote smb user (smb_uid):		      */
		/* 	1) Query Winbind (or other local pam/nss daemon       */
		/* 	  for userid/password/logon_domain or credential      */
		/*      2) Query Winbind for uid to sid to username mapping   */
		/* 	   and see if we have a matching password for existing*/
		/*         session for that user perhas getting password by   */
		/*         adding a new pam_cifs module that stores passwords */
		/*         so that the cifs vfs can get at that for all logged*/
		/*	   on users					      */
		/*	3) (Which is the mechanism we have chosen)	      */
		/*	   Search through sessions to the same server for a   */
		/*	   a match on the uid that was passed in on mount     */
		/*         with the current processes uid (or euid?) and use  */
		/* 	   that smb uid.   If no existing smb session for     */
		/* 	   that uid found, use the default smb session ie     */
		/*         the smb session for the volume mounted which is    */
		/* 	   the same as would be used if the multiuser mount   */
		/* 	   flag were disabled.  */

		/*  BB Add support for establishing new tCon and SMB Session  */
		/*      with userid/password pairs found on the smb session   */ 
		/*	for other target tcp/ip addresses 		BB    */
				if(current->uid != treeCon->ses->linux_uid) {
					cFYI(1,("Multiuser mode and UID did not match tcon uid "));
					read_lock(&GlobalSMBSeslock);
					list_for_each(temp_item, &GlobalSMBSessionList) {
						ses = list_entry(temp_item, struct cifsSesInfo, cifsSessionList);
						if(ses->linux_uid == current->uid) {
							if(ses->server == treeCon->ses->server) {
								cFYI(1,("found matching uid substitute right smb_uid"));  
								buffer->Uid = ses->Suid;
								break;
							} else {
								/* BB eventually call cifs_setup_session here */
								cFYI(1,("local UID found but smb sess with this server does not exist"));  
							}
						}
					}
					read_unlock(&GlobalSMBSeslock);
				}
			}
		}
		if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
			buffer->Flags2 |= SMBFLG2_DFS;
		if((treeCon->ses) && (treeCon->ses->server))
			if(treeCon->ses->server->secMode & 
			  (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
				buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
	}

/*  endian conversion of flags is now done just before sending */
	buffer->WordCount = (char) word_count;
	return;
}

int
checkSMBhdr(struct smb_hdr *smb, __u16 mid)
{
	/* Make sure that this really is an SMB, that it is a response, 
	   and that the message ids match */
	if ((*(__le32 *) smb->Protocol == cpu_to_le32(0x424d53ff)) && 
		(mid == smb->Mid)) {    
		if(smb->Flags & SMBFLG_RESPONSE)
			return 0;                    
		else {        
		/* only one valid case where server sends us request */
			if(smb->Command == SMB_COM_LOCKING_ANDX)
				return 0;
			else
				cERROR(1, ("Rcvd Request not response "));         
		}
	} else { /* bad signature or mid */
		if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff))
			cERROR(1,
			       ("Bad protocol string signature header %x ",
				*(unsigned int *) smb->Protocol));
		if (mid != smb->Mid)
			cERROR(1, ("Mids do not match"));
	}
	cERROR(1, ("bad smb detected. The Mid=%d", smb->Mid));
	return 1;
}

int
checkSMB(struct smb_hdr *smb, __u16 mid, int length)
{
	__u32 len = be32_to_cpu(smb->smb_buf_length);
	cFYI(0,
	     ("Entering checkSMB with Length: %x, smb_buf_length: %x ",
	      length, len));
	if (((unsigned int)length < 2 + sizeof (struct smb_hdr)) ||
	    (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4)) {
		if ((unsigned int)length < 2 + sizeof (struct smb_hdr)) {
			if (((unsigned int)length >= 
				sizeof (struct smb_hdr) - 1)
			    && (smb->Status.CifsError != 0)) {
				smb->WordCount = 0;
				return 0;	/* some error cases do not return wct and bcc */
			} else {
				cERROR(1, ("Length less than smb header size"));
			}

		}
		if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4)
			cERROR(1,
			       ("smb_buf_length greater than MaxBufSize"));
		cERROR(1,
		       ("bad smb detected. Illegal length. The mid=%d",
			smb->Mid));
		return 1;
	}

	if (checkSMBhdr(smb, mid))
		return 1;

	if ((4 + len != smbCalcSize(smb))
	    || (4 + len != (unsigned int)length)) {
		return 0;
	} else {
		cERROR(1, ("smbCalcSize %x ", smbCalcSize(smb)));
		cERROR(1,
		       ("bad smb size detected. The Mid=%d", smb->Mid));
		return 1;
	}
}
int
is_valid_oplock_break(struct smb_hdr *buf)
{    
	struct smb_com_lock_req * pSMB = (struct smb_com_lock_req *)buf;
	struct list_head *tmp;
	struct list_head *tmp1;
	struct cifsTconInfo *tcon;
	struct cifsFileInfo *netfile;

	cFYI(1,("Checking for oplock break or dnotify response"));
	if((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
	   (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {
		struct smb_com_transaction_change_notify_rsp * pSMBr =
			(struct smb_com_transaction_change_notify_rsp *)buf;
		struct file_notify_information * pnotify;
		__u32 data_offset = 0;
		if(pSMBr->ByteCount > sizeof(struct file_notify_information)) {
			data_offset = le32_to_cpu(pSMBr->DataOffset);

			pnotify = (struct file_notify_information *)((char *)&pSMBr->hdr.Protocol
				+ data_offset);
			cFYI(1,("dnotify on %s with action: 0x%x",pnotify->FileName,
				pnotify->Action));  /* BB removeme BB */
	             /*   cifs_dump_mem("Received notify Data is: ",buf,sizeof(struct smb_hdr)+60); */
			return TRUE;
		}
		if(pSMBr->hdr.Status.CifsError) {
			cFYI(1,("notify err 0x%d",pSMBr->hdr.Status.CifsError));
			return TRUE;
		}
		return FALSE;
	}  
	if(pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
		return FALSE;
	if(pSMB->hdr.Flags & SMBFLG_RESPONSE) {
		/* no sense logging error on invalid handle on oplock
		   break - harmless race between close request and oplock
		   break response is expected from time to time writing out
		   large dirty files cached on the client */
		if ((NT_STATUS_INVALID_HANDLE) == 
		   le32_to_cpu(pSMB->hdr.Status.CifsError)) { 
			cFYI(1,("invalid handle on oplock break"));
			return TRUE;
		} else if (ERRbadfid == 
		   le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
			return TRUE;	  
		} else {
			return FALSE; /* on valid oplock brk we get "request" */
		}
	}
	if(pSMB->hdr.WordCount != 8)
		return FALSE;

	cFYI(1,(" oplock type 0x%d level 0x%d",pSMB->LockType,pSMB->OplockLevel));
	if(!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
		return FALSE;    

	/* look up tcon based on tid & uid */
	read_lock(&GlobalSMBSeslock);
	list_for_each(tmp, &GlobalTreeConnectionList) {
		tcon = list_entry(tmp, struct cifsTconInfo, cifsConnectionList);
		if (tcon->tid == buf->Tid) {
#ifdef CONFIG_CIFS_STATS
			atomic_inc(&tcon->num_oplock_brks);
#endif
			list_for_each(tmp1,&tcon->openFileList){
				netfile = list_entry(tmp1,struct cifsFileInfo,tlist);
				if(pSMB->Fid == netfile->netfid) {
					struct cifsInodeInfo *pCifsInode;
					read_unlock(&GlobalSMBSeslock);
					cFYI(1,("Matching file id, processing oplock break"));
					pCifsInode = 
						CIFS_I(netfile->pInode);
					pCifsInode->clientCanCacheAll = FALSE;
					if(pSMB->OplockLevel == 0)
						pCifsInode->clientCanCacheRead = FALSE;
					pCifsInode->oplockPending = TRUE;
					AllocOplockQEntry(netfile->pInode, netfile->netfid, tcon);
					cFYI(1,("about to wake up oplock thd"));
					wake_up_process(oplockThread);               
					return TRUE;
				}
			}
			read_unlock(&GlobalSMBSeslock);
			cFYI(1,("No matching file for oplock break on connection"));
			return TRUE;
		}
	}
	read_unlock(&GlobalSMBSeslock);
	cFYI(1,("Can not process oplock break for non-existent connection"));
	return TRUE;
}

void
dump_smb(struct smb_hdr *smb_buf, int smb_buf_length)
{
	int i, j;
	char debug_line[17];
	unsigned char *buffer;

	if (traceSMB == 0)
		return;

	buffer = (unsigned char *) smb_buf;
	for (i = 0, j = 0; i < smb_buf_length; i++, j++) {
		if (i % 8 == 0) {	/* we have reached the beginning of line  */
			printk(KERN_DEBUG "| ");
			j = 0;
		}
		printk("%0#4x ", buffer[i]);
		debug_line[2 * j] = ' ';
		if (isprint(buffer[i]))
			debug_line[1 + (2 * j)] = buffer[i];
		else
			debug_line[1 + (2 * j)] = '_';

		if (i % 8 == 7) {	/* we have reached end of line, time to print ascii */
			debug_line[16] = 0;
			printk(" | %s\n", debug_line);
		}
	}
	for (; j < 8; j++) {
		printk("     ");
		debug_line[2 * j] = ' ';
		debug_line[1 + (2 * j)] = ' ';
	}
	printk( " | %s\n", debug_line);
	return;
}

#ifdef CONFIG_CIFS_EXPERIMENTAL
/* Windows maps these to the user defined 16 bit Unicode range since they are
   reserved symbols (along with \ and /), otherwise illegal to store
   in filenames in NTFS */
#define UNI_ASTERIK     cpu_to_le16('*' + 0xF000)
#define UNI_QUESTION    cpu_to_le16('?' + 0xF000)
#define UNI_COLON       cpu_to_le16(':' + 0xF000)
#define UNI_GRTRTHAN    cpu_to_le16('>' + 0xF000)
#define UNI_LESSTHAN    cpu_to_le16('<' + 0xF000)
#define UNI_PIPE        cpu_to_le16('|' + 0xF000)
#define UNI_SLASH       cpu_to_le16('\\' + 0xF000)

/* Convert 16 bit Unicode pathname from wire format to string in current code
   page.  Conversion may involve remapping up the seven characters that are
   only legal in POSIX-like OS (if they are present in the string). Path
   names are little endian 16 bit Unicode on the wire */
int
cifs_convertUCSpath(char *target, const __le16 * source, int maxlen,
		    const struct nls_table * cp)
{
	int i,j,len;
	wchar_t src_char;

	for(i = 0, j = 0; i < maxlen; i++) {
		src_char = le16_to_cpu(source[i]);
		switch (src_char) {
			case 0:
				goto cUCS_out; /* BB check this BB */
			case UNI_COLON:
				target[j] = ':';
				break;
			case UNI_ASTERIK:
				target[j] = '*';
				break;
			case UNI_QUESTION:
				target[j] = '?';
				break;
			case UNI_SLASH:
				target[j] = '\\'; /* BB check this - is there risk here of converting path sep BB */
				break;
			case UNI_PIPE:
				target[j] = '|';
				break;
			case UNI_GRTRTHAN:
				target[j] = '>';
				break;
			case UNI_LESSTHAN:
				target[j] = '<';
			default: 
				len = cp->uni2char(src_char, &target[j], 
						NLS_MAX_CHARSET_SIZE);
				if(len > 0) {
					j += len;
					continue;
				} else {
					target[j] = '?';
				}
		}
		j++;
		/* check to make sure we do not overrun callers allocated temp buffer */
		if(j >= (2 * NAME_MAX))
			break;
	}
cUCS_out:
	target[j] = 0;
	return j;
}
#endif /* CIFS_EXPERIMENTAL */