4 * Copyright (C) International Business Machines Corp., 2002,2008
5 * Author(s): Steve French (sfrench@us.ibm.com)
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 * the GNU Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <linux/slab.h>
23 #include <linux/ctype.h>
24 #include <linux/mempool.h>
27 #include "cifsproto.h"
28 #include "cifs_debug.h"
31 #include "cifs_unicode.h"
33 extern mempool_t
*cifs_sm_req_poolp
;
34 extern mempool_t
*cifs_req_poolp
;
36 /* The xid serves as a useful identifier for each incoming vfs request,
37 in a similar way to the mid which is useful to track each sent smb,
38 and CurrentXid can also provide a running counter (although it
39 will eventually wrap past zero) of the total vfs operations handled
40 since the cifs fs was mounted */
47 spin_lock(&GlobalMid_Lock
);
48 GlobalTotalActiveXid
++;
50 /* keep high water mark for number of simultaneous ops in filesystem */
51 if (GlobalTotalActiveXid
> GlobalMaxActiveXid
)
52 GlobalMaxActiveXid
= GlobalTotalActiveXid
;
53 if (GlobalTotalActiveXid
> 65000)
54 cFYI(1, "warning: more than 65000 requests active");
55 xid
= GlobalCurrentXid
++;
56 spin_unlock(&GlobalMid_Lock
);
61 _FreeXid(unsigned int xid
)
63 spin_lock(&GlobalMid_Lock
);
64 /* if (GlobalTotalActiveXid == 0)
66 GlobalTotalActiveXid
--;
67 spin_unlock(&GlobalMid_Lock
);
73 struct cifsSesInfo
*ret_buf
;
75 ret_buf
= kzalloc(sizeof(struct cifsSesInfo
), GFP_KERNEL
);
77 atomic_inc(&sesInfoAllocCount
);
78 ret_buf
->status
= CifsNew
;
80 INIT_LIST_HEAD(&ret_buf
->smb_ses_list
);
81 INIT_LIST_HEAD(&ret_buf
->tcon_list
);
82 mutex_init(&ret_buf
->session_mutex
);
88 sesInfoFree(struct cifsSesInfo
*buf_to_free
)
90 if (buf_to_free
== NULL
) {
91 cFYI(1, "Null buffer passed to sesInfoFree");
95 atomic_dec(&sesInfoAllocCount
);
96 kfree(buf_to_free
->serverOS
);
97 kfree(buf_to_free
->serverDomain
);
98 kfree(buf_to_free
->serverNOS
);
99 if (buf_to_free
->password
) {
100 memset(buf_to_free
->password
, 0, strlen(buf_to_free
->password
));
101 kfree(buf_to_free
->password
);
103 kfree(buf_to_free
->user_name
);
104 kfree(buf_to_free
->domainName
);
108 struct cifsTconInfo
*
111 struct cifsTconInfo
*ret_buf
;
112 ret_buf
= kzalloc(sizeof(struct cifsTconInfo
), GFP_KERNEL
);
114 atomic_inc(&tconInfoAllocCount
);
115 ret_buf
->tidStatus
= CifsNew
;
117 INIT_LIST_HEAD(&ret_buf
->openFileList
);
118 INIT_LIST_HEAD(&ret_buf
->tcon_list
);
119 #ifdef CONFIG_CIFS_STATS
120 spin_lock_init(&ret_buf
->stat_lock
);
127 tconInfoFree(struct cifsTconInfo
*buf_to_free
)
129 if (buf_to_free
== NULL
) {
130 cFYI(1, "Null buffer passed to tconInfoFree");
133 atomic_dec(&tconInfoAllocCount
);
134 kfree(buf_to_free
->nativeFileSystem
);
135 if (buf_to_free
->password
) {
136 memset(buf_to_free
->password
, 0, strlen(buf_to_free
->password
));
137 kfree(buf_to_free
->password
);
145 struct smb_hdr
*ret_buf
= NULL
;
147 /* We could use negotiated size instead of max_msgsize -
148 but it may be more efficient to always alloc same size
149 albeit slightly larger than necessary and maxbuffersize
150 defaults to this and can not be bigger */
151 ret_buf
= mempool_alloc(cifs_req_poolp
, GFP_NOFS
);
153 /* clear the first few header bytes */
154 /* for most paths, more is cleared in header_assemble */
156 memset(ret_buf
, 0, sizeof(struct smb_hdr
) + 3);
157 atomic_inc(&bufAllocCount
);
158 #ifdef CONFIG_CIFS_STATS2
159 atomic_inc(&totBufAllocCount
);
160 #endif /* CONFIG_CIFS_STATS2 */
167 cifs_buf_release(void *buf_to_free
)
169 if (buf_to_free
== NULL
) {
170 /* cFYI(1, "Null buffer passed to cifs_buf_release");*/
173 mempool_free(buf_to_free
, cifs_req_poolp
);
175 atomic_dec(&bufAllocCount
);
180 cifs_small_buf_get(void)
182 struct smb_hdr
*ret_buf
= NULL
;
184 /* We could use negotiated size instead of max_msgsize -
185 but it may be more efficient to always alloc same size
186 albeit slightly larger than necessary and maxbuffersize
187 defaults to this and can not be bigger */
188 ret_buf
= mempool_alloc(cifs_sm_req_poolp
, GFP_NOFS
);
190 /* No need to clear memory here, cleared in header assemble */
191 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
192 atomic_inc(&smBufAllocCount
);
193 #ifdef CONFIG_CIFS_STATS2
194 atomic_inc(&totSmBufAllocCount
);
195 #endif /* CONFIG_CIFS_STATS2 */
202 cifs_small_buf_release(void *buf_to_free
)
205 if (buf_to_free
== NULL
) {
206 cFYI(1, "Null buffer passed to cifs_small_buf_release");
209 mempool_free(buf_to_free
, cifs_sm_req_poolp
);
211 atomic_dec(&smBufAllocCount
);
216 Find a free multiplex id (SMB mid). Otherwise there could be
217 mid collisions which might cause problems, demultiplexing the
218 wrong response to this request. Multiplex ids could collide if
219 one of a series requests takes much longer than the others, or
220 if a very large number of long lived requests (byte range
221 locks or FindNotify requests) are pending. No more than
222 64K-1 requests can be outstanding at one time. If no
223 mids are available, return zero. A future optimization
224 could make the combination of mids and uid the key we use
225 to demultiplex on (rather than mid alone).
226 In addition to the above check, the cifs demultiplex
227 code already used the command code as a secondary
228 check of the frame and if signing is negotiated the
229 response would be discarded if the mid were the same
230 but the signature was wrong. Since the mid is not put in the
231 pending queue until later (when it is about to be dispatched)
232 we do have to limit the number of outstanding requests
233 to somewhat less than 64K-1 although it is hard to imagine
234 so many threads being in the vfs at one time.
236 __u16
GetNextMid(struct TCP_Server_Info
*server
)
242 spin_lock(&GlobalMid_Lock
);
243 last_mid
= server
->CurrentMid
; /* we do not want to loop forever */
244 server
->CurrentMid
++;
245 /* This nested loop looks more expensive than it is.
246 In practice the list of pending requests is short,
247 fewer than 50, and the mids are likely to be unique
248 on the first pass through the loop unless some request
249 takes longer than the 64 thousand requests before it
250 (and it would also have to have been a request that
252 while (server
->CurrentMid
!= last_mid
) {
253 struct mid_q_entry
*mid_entry
;
254 unsigned int num_mids
;
257 if (server
->CurrentMid
== 0)
258 server
->CurrentMid
++;
261 list_for_each_entry(mid_entry
, &server
->pending_mid_q
, qhead
) {
263 if (mid_entry
->mid
== server
->CurrentMid
&&
264 mid_entry
->midState
== MID_REQUEST_SUBMITTED
) {
265 /* This mid is in use, try a different one */
272 * if we have more than 32k mids in the list, then something
273 * is very wrong. Possibly a local user is trying to DoS the
274 * box by issuing long-running calls and SIGKILL'ing them. If
275 * we get to 2^16 mids then we're in big trouble as this
276 * function could loop forever.
278 * Go ahead and assign out the mid in this situation, but force
279 * an eventual reconnect to clean out the pending_mid_q.
281 if (num_mids
> 32768)
282 server
->tcpStatus
= CifsNeedReconnect
;
285 mid
= server
->CurrentMid
;
288 server
->CurrentMid
++;
290 spin_unlock(&GlobalMid_Lock
);
294 /* NB: MID can not be set if treeCon not passed in, in that
295 case it is responsbility of caller to set the mid */
297 header_assemble(struct smb_hdr
*buffer
, char smb_command
/* command */ ,
298 const struct cifsTconInfo
*treeCon
, int word_count
299 /* length of fixed section (word count) in two byte units */)
301 struct list_head
*temp_item
;
302 struct cifsSesInfo
*ses
;
303 char *temp
= (char *) buffer
;
305 memset(temp
, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
307 buffer
->smb_buf_length
=
308 (2 * word_count
) + sizeof(struct smb_hdr
) -
309 4 /* RFC 1001 length field does not count */ +
310 2 /* for bcc field itself */ ;
311 /* Note that this is the only network field that has to be converted
312 to big endian and it is done just before we send it */
314 buffer
->Protocol
[0] = 0xFF;
315 buffer
->Protocol
[1] = 'S';
316 buffer
->Protocol
[2] = 'M';
317 buffer
->Protocol
[3] = 'B';
318 buffer
->Command
= smb_command
;
319 buffer
->Flags
= 0x00; /* case sensitive */
320 buffer
->Flags2
= SMBFLG2_KNOWS_LONG_NAMES
;
321 buffer
->Pid
= cpu_to_le16((__u16
)current
->tgid
);
322 buffer
->PidHigh
= cpu_to_le16((__u16
)(current
->tgid
>> 16));
324 buffer
->Tid
= treeCon
->tid
;
326 if (treeCon
->ses
->capabilities
& CAP_UNICODE
)
327 buffer
->Flags2
|= SMBFLG2_UNICODE
;
328 if (treeCon
->ses
->capabilities
& CAP_STATUS32
)
329 buffer
->Flags2
|= SMBFLG2_ERR_STATUS
;
331 /* Uid is not converted */
332 buffer
->Uid
= treeCon
->ses
->Suid
;
333 buffer
->Mid
= GetNextMid(treeCon
->ses
->server
);
334 if (multiuser_mount
!= 0) {
335 /* For the multiuser case, there are few obvious technically */
336 /* possible mechanisms to match the local linux user (uid) */
337 /* to a valid remote smb user (smb_uid): */
338 /* 1) Query Winbind (or other local pam/nss daemon */
339 /* for userid/password/logon_domain or credential */
340 /* 2) Query Winbind for uid to sid to username mapping */
341 /* and see if we have a matching password for existing*/
342 /* session for that user perhas getting password by */
343 /* adding a new pam_cifs module that stores passwords */
344 /* so that the cifs vfs can get at that for all logged*/
346 /* 3) (Which is the mechanism we have chosen) */
347 /* Search through sessions to the same server for a */
348 /* a match on the uid that was passed in on mount */
349 /* with the current processes uid (or euid?) and use */
350 /* that smb uid. If no existing smb session for */
351 /* that uid found, use the default smb session ie */
352 /* the smb session for the volume mounted which is */
353 /* the same as would be used if the multiuser mount */
354 /* flag were disabled. */
356 /* BB Add support for establishing new tCon and SMB Session */
357 /* with userid/password pairs found on the smb session */
358 /* for other target tcp/ip addresses BB */
359 if (current_fsuid() != treeCon
->ses
->linux_uid
) {
360 cFYI(1, "Multiuser mode and UID "
361 "did not match tcon uid");
362 spin_lock(&cifs_tcp_ses_lock
);
363 list_for_each(temp_item
, &treeCon
->ses
->server
->smb_ses_list
) {
364 ses
= list_entry(temp_item
, struct cifsSesInfo
, smb_ses_list
);
365 if (ses
->linux_uid
== current_fsuid()) {
366 if (ses
->server
== treeCon
->ses
->server
) {
367 cFYI(1, "found matching uid substitute right smb_uid");
368 buffer
->Uid
= ses
->Suid
;
371 /* BB eventually call cifs_setup_session here */
372 cFYI(1, "local UID found but no smb sess with this server exists");
376 spin_unlock(&cifs_tcp_ses_lock
);
380 if (treeCon
->Flags
& SMB_SHARE_IS_IN_DFS
)
381 buffer
->Flags2
|= SMBFLG2_DFS
;
383 buffer
->Flags
|= SMBFLG_CASELESS
;
384 if ((treeCon
->ses
) && (treeCon
->ses
->server
))
385 if (treeCon
->ses
->server
->secMode
&
386 (SECMODE_SIGN_REQUIRED
| SECMODE_SIGN_ENABLED
))
387 buffer
->Flags2
|= SMBFLG2_SECURITY_SIGNATURE
;
390 /* endian conversion of flags is now done just before sending */
391 buffer
->WordCount
= (char) word_count
;
396 check_smb_hdr(struct smb_hdr
*smb
, __u16 mid
)
398 /* does it have the right SMB "signature" ? */
399 if (*(__le32
*) smb
->Protocol
!= cpu_to_le32(0x424d53ff)) {
400 cERROR(1, "Bad protocol string signature header 0x%x",
401 *(unsigned int *)smb
->Protocol
);
405 /* Make sure that message ids match */
406 if (mid
!= smb
->Mid
) {
407 cERROR(1, "Mids do not match. received=%u expected=%u",
412 /* if it's a response then accept */
413 if (smb
->Flags
& SMBFLG_RESPONSE
)
416 /* only one valid case where server sends us request */
417 if (smb
->Command
== SMB_COM_LOCKING_ANDX
)
420 cERROR(1, "Server sent request, not response. mid=%u", smb
->Mid
);
425 checkSMB(struct smb_hdr
*smb
, __u16 mid
, unsigned int length
)
427 __u32 len
= smb
->smb_buf_length
;
428 __u32 clc_len
; /* calculated length */
429 cFYI(0, "checkSMB Length: 0x%x, smb_buf_length: 0x%x", length
, len
);
431 if (length
< 2 + sizeof(struct smb_hdr
)) {
432 if ((length
>= sizeof(struct smb_hdr
) - 1)
433 && (smb
->Status
.CifsError
!= 0)) {
435 /* some error cases do not return wct and bcc */
437 } else if ((length
== sizeof(struct smb_hdr
) + 1) &&
438 (smb
->WordCount
== 0)) {
439 char *tmp
= (char *)smb
;
440 /* Need to work around a bug in two servers here */
441 /* First, check if the part of bcc they sent was zero */
442 if (tmp
[sizeof(struct smb_hdr
)] == 0) {
443 /* some servers return only half of bcc
444 * on simple responses (wct, bcc both zero)
445 * in particular have seen this on
446 * ulogoffX and FindClose. This leaves
447 * one byte of bcc potentially unitialized
449 /* zero rest of bcc */
450 tmp
[sizeof(struct smb_hdr
)+1] = 0;
453 cERROR(1, "rcvd invalid byte count (bcc)");
455 cERROR(1, "Length less than smb header size");
459 if (len
> CIFSMaxBufSize
+ MAX_CIFS_HDR_SIZE
- 4) {
460 cERROR(1, "smb length greater than MaxBufSize, mid=%d",
465 if (check_smb_hdr(smb
, mid
))
467 clc_len
= smbCalcSize_LE(smb
);
469 if (4 + len
!= length
) {
470 cERROR(1, "Length read does not match RFC1001 length %d",
475 if (4 + len
!= clc_len
) {
476 /* check if bcc wrapped around for large read responses */
477 if ((len
> 64 * 1024) && (len
> clc_len
)) {
478 /* check if lengths match mod 64K */
479 if (((4 + len
) & 0xFFFF) == (clc_len
& 0xFFFF))
480 return 0; /* bcc wrapped */
482 cFYI(1, "Calculated size %u vs length %u mismatch for mid=%u",
483 clc_len
, 4 + len
, smb
->Mid
);
485 if (4 + len
< clc_len
) {
486 cERROR(1, "RFC1001 size %u smaller than SMB for mid=%u",
489 } else if (len
> clc_len
+ 512) {
491 * Some servers (Windows XP in particular) send more
492 * data than the lengths in the SMB packet would
493 * indicate on certain calls (byte range locks and
494 * trans2 find first calls in particular). While the
495 * client can handle such a frame by ignoring the
496 * trailing data, we choose limit the amount of extra
499 cERROR(1, "RFC1001 size %u more than 512 bytes larger "
500 "than SMB for mid=%u", len
, smb
->Mid
);
508 is_valid_oplock_break(struct smb_hdr
*buf
, struct TCP_Server_Info
*srv
)
510 struct smb_com_lock_req
*pSMB
= (struct smb_com_lock_req
*)buf
;
511 struct list_head
*tmp
, *tmp1
, *tmp2
;
512 struct cifsSesInfo
*ses
;
513 struct cifsTconInfo
*tcon
;
514 struct cifsInodeInfo
*pCifsInode
;
515 struct cifsFileInfo
*netfile
;
517 cFYI(1, "Checking for oplock break or dnotify response");
518 if ((pSMB
->hdr
.Command
== SMB_COM_NT_TRANSACT
) &&
519 (pSMB
->hdr
.Flags
& SMBFLG_RESPONSE
)) {
520 struct smb_com_transaction_change_notify_rsp
*pSMBr
=
521 (struct smb_com_transaction_change_notify_rsp
*)buf
;
522 struct file_notify_information
*pnotify
;
523 __u32 data_offset
= 0;
524 if (get_bcc_le(buf
) > sizeof(struct file_notify_information
)) {
525 data_offset
= le32_to_cpu(pSMBr
->DataOffset
);
527 pnotify
= (struct file_notify_information
*)
528 ((char *)&pSMBr
->hdr
.Protocol
+ data_offset
);
529 cFYI(1, "dnotify on %s Action: 0x%x",
530 pnotify
->FileName
, pnotify
->Action
);
531 /* cifs_dump_mem("Rcvd notify Data: ",buf,
532 sizeof(struct smb_hdr)+60); */
535 if (pSMBr
->hdr
.Status
.CifsError
) {
536 cFYI(1, "notify err 0x%d",
537 pSMBr
->hdr
.Status
.CifsError
);
542 if (pSMB
->hdr
.Command
!= SMB_COM_LOCKING_ANDX
)
544 if (pSMB
->hdr
.Flags
& SMBFLG_RESPONSE
) {
545 /* no sense logging error on invalid handle on oplock
546 break - harmless race between close request and oplock
547 break response is expected from time to time writing out
548 large dirty files cached on the client */
549 if ((NT_STATUS_INVALID_HANDLE
) ==
550 le32_to_cpu(pSMB
->hdr
.Status
.CifsError
)) {
551 cFYI(1, "invalid handle on oplock break");
553 } else if (ERRbadfid
==
554 le16_to_cpu(pSMB
->hdr
.Status
.DosError
.Error
)) {
557 return false; /* on valid oplock brk we get "request" */
560 if (pSMB
->hdr
.WordCount
!= 8)
563 cFYI(1, "oplock type 0x%d level 0x%d",
564 pSMB
->LockType
, pSMB
->OplockLevel
);
565 if (!(pSMB
->LockType
& LOCKING_ANDX_OPLOCK_RELEASE
))
568 /* look up tcon based on tid & uid */
569 spin_lock(&cifs_tcp_ses_lock
);
570 list_for_each(tmp
, &srv
->smb_ses_list
) {
571 ses
= list_entry(tmp
, struct cifsSesInfo
, smb_ses_list
);
572 list_for_each(tmp1
, &ses
->tcon_list
) {
573 tcon
= list_entry(tmp1
, struct cifsTconInfo
, tcon_list
);
574 if (tcon
->tid
!= buf
->Tid
)
577 cifs_stats_inc(&tcon
->num_oplock_brks
);
578 spin_lock(&cifs_file_list_lock
);
579 list_for_each(tmp2
, &tcon
->openFileList
) {
580 netfile
= list_entry(tmp2
, struct cifsFileInfo
,
582 if (pSMB
->Fid
!= netfile
->netfid
)
585 cFYI(1, "file id match, oplock break");
586 pCifsInode
= CIFS_I(netfile
->dentry
->d_inode
);
588 cifs_set_oplock_level(pCifsInode
,
589 pSMB
->OplockLevel
? OPLOCK_READ
: 0);
591 * cifs_oplock_break_put() can't be called
592 * from here. Get reference after queueing
593 * succeeded. cifs_oplock_break() will
594 * synchronize using cifs_file_list_lock.
596 if (queue_work(system_nrt_wq
,
597 &netfile
->oplock_break
))
598 cifs_oplock_break_get(netfile
);
599 netfile
->oplock_break_cancelled
= false;
601 spin_unlock(&cifs_file_list_lock
);
602 spin_unlock(&cifs_tcp_ses_lock
);
605 spin_unlock(&cifs_file_list_lock
);
606 spin_unlock(&cifs_tcp_ses_lock
);
607 cFYI(1, "No matching file for oplock break");
611 spin_unlock(&cifs_tcp_ses_lock
);
612 cFYI(1, "Can not process oplock break for non-existent connection");
617 dump_smb(struct smb_hdr
*smb_buf
, int smb_buf_length
)
621 unsigned char *buffer
;
626 buffer
= (unsigned char *) smb_buf
;
627 for (i
= 0, j
= 0; i
< smb_buf_length
; i
++, j
++) {
629 /* have reached the beginning of line */
630 printk(KERN_DEBUG
"| ");
633 printk("%0#4x ", buffer
[i
]);
634 debug_line
[2 * j
] = ' ';
635 if (isprint(buffer
[i
]))
636 debug_line
[1 + (2 * j
)] = buffer
[i
];
638 debug_line
[1 + (2 * j
)] = '_';
641 /* reached end of line, time to print ascii */
643 printk(" | %s\n", debug_line
);
648 debug_line
[2 * j
] = ' ';
649 debug_line
[1 + (2 * j
)] = ' ';
651 printk(" | %s\n", debug_line
);
656 cifs_autodisable_serverino(struct cifs_sb_info
*cifs_sb
)
658 if (cifs_sb
->mnt_cifs_flags
& CIFS_MOUNT_SERVER_INUM
) {
659 cifs_sb
->mnt_cifs_flags
&= ~CIFS_MOUNT_SERVER_INUM
;
660 cERROR(1, "Autodisabling the use of server inode numbers on "
661 "%s. This server doesn't seem to support them "
662 "properly. Hardlinks will not be recognized on this "
663 "mount. Consider mounting with the \"noserverino\" "
664 "option to silence this message.",
665 cifs_sb_master_tcon(cifs_sb
)->treeName
);
669 void cifs_set_oplock_level(struct cifsInodeInfo
*cinode
, __u32 oplock
)
673 if (oplock
== OPLOCK_EXCLUSIVE
) {
674 cinode
->clientCanCacheAll
= true;
675 cinode
->clientCanCacheRead
= true;
676 cFYI(1, "Exclusive Oplock granted on inode %p",
678 } else if (oplock
== OPLOCK_READ
) {
679 cinode
->clientCanCacheAll
= false;
680 cinode
->clientCanCacheRead
= true;
681 cFYI(1, "Level II Oplock granted on inode %p",
684 cinode
->clientCanCacheAll
= false;
685 cinode
->clientCanCacheRead
= false;