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 cifs_ses
*ret_buf
;
75 ret_buf
= kzalloc(sizeof(struct cifs_ses
), 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 cifs_ses
*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
);
111 struct cifs_tcon
*ret_buf
;
112 ret_buf
= kzalloc(sizeof(struct cifs_tcon
), 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 cifs_tcon
*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 cifs_tcon
*treeCon
, int word_count
299 /* length of fixed section (word count) in two byte units */)
301 struct list_head
*temp_item
;
302 struct cifs_ses
*ses
;
303 char *temp
= (char *) buffer
;
305 memset(temp
, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
307 buffer
->smb_buf_length
= cpu_to_be32(
308 (2 * word_count
) + sizeof(struct smb_hdr
) -
309 4 /* RFC 1001 length field does not count */ +
310 2 /* for bcc field itself */) ;
312 buffer
->Protocol
[0] = 0xFF;
313 buffer
->Protocol
[1] = 'S';
314 buffer
->Protocol
[2] = 'M';
315 buffer
->Protocol
[3] = 'B';
316 buffer
->Command
= smb_command
;
317 buffer
->Flags
= 0x00; /* case sensitive */
318 buffer
->Flags2
= SMBFLG2_KNOWS_LONG_NAMES
;
319 buffer
->Pid
= cpu_to_le16((__u16
)current
->tgid
);
320 buffer
->PidHigh
= cpu_to_le16((__u16
)(current
->tgid
>> 16));
322 buffer
->Tid
= treeCon
->tid
;
324 if (treeCon
->ses
->capabilities
& CAP_UNICODE
)
325 buffer
->Flags2
|= SMBFLG2_UNICODE
;
326 if (treeCon
->ses
->capabilities
& CAP_STATUS32
)
327 buffer
->Flags2
|= SMBFLG2_ERR_STATUS
;
329 /* Uid is not converted */
330 buffer
->Uid
= treeCon
->ses
->Suid
;
331 buffer
->Mid
= GetNextMid(treeCon
->ses
->server
);
332 if (multiuser_mount
!= 0) {
333 /* For the multiuser case, there are few obvious technically */
334 /* possible mechanisms to match the local linux user (uid) */
335 /* to a valid remote smb user (smb_uid): */
336 /* 1) Query Winbind (or other local pam/nss daemon */
337 /* for userid/password/logon_domain or credential */
338 /* 2) Query Winbind for uid to sid to username mapping */
339 /* and see if we have a matching password for existing*/
340 /* session for that user perhas getting password by */
341 /* adding a new pam_cifs module that stores passwords */
342 /* so that the cifs vfs can get at that for all logged*/
344 /* 3) (Which is the mechanism we have chosen) */
345 /* Search through sessions to the same server for a */
346 /* a match on the uid that was passed in on mount */
347 /* with the current processes uid (or euid?) and use */
348 /* that smb uid. If no existing smb session for */
349 /* that uid found, use the default smb session ie */
350 /* the smb session for the volume mounted which is */
351 /* the same as would be used if the multiuser mount */
352 /* flag were disabled. */
354 /* BB Add support for establishing new tCon and SMB Session */
355 /* with userid/password pairs found on the smb session */
356 /* for other target tcp/ip addresses BB */
357 if (current_fsuid() != treeCon
->ses
->linux_uid
) {
358 cFYI(1, "Multiuser mode and UID "
359 "did not match tcon uid");
360 spin_lock(&cifs_tcp_ses_lock
);
361 list_for_each(temp_item
, &treeCon
->ses
->server
->smb_ses_list
) {
362 ses
= list_entry(temp_item
, struct cifs_ses
, smb_ses_list
);
363 if (ses
->linux_uid
== current_fsuid()) {
364 if (ses
->server
== treeCon
->ses
->server
) {
365 cFYI(1, "found matching uid substitute right smb_uid");
366 buffer
->Uid
= ses
->Suid
;
369 /* BB eventually call cifs_setup_session here */
370 cFYI(1, "local UID found but no smb sess with this server exists");
374 spin_unlock(&cifs_tcp_ses_lock
);
378 if (treeCon
->Flags
& SMB_SHARE_IS_IN_DFS
)
379 buffer
->Flags2
|= SMBFLG2_DFS
;
381 buffer
->Flags
|= SMBFLG_CASELESS
;
382 if ((treeCon
->ses
) && (treeCon
->ses
->server
))
383 if (treeCon
->ses
->server
->sec_mode
&
384 (SECMODE_SIGN_REQUIRED
| SECMODE_SIGN_ENABLED
))
385 buffer
->Flags2
|= SMBFLG2_SECURITY_SIGNATURE
;
388 /* endian conversion of flags is now done just before sending */
389 buffer
->WordCount
= (char) word_count
;
394 check_smb_hdr(struct smb_hdr
*smb
, __u16 mid
)
396 /* does it have the right SMB "signature" ? */
397 if (*(__le32
*) smb
->Protocol
!= cpu_to_le32(0x424d53ff)) {
398 cERROR(1, "Bad protocol string signature header 0x%x",
399 *(unsigned int *)smb
->Protocol
);
403 /* Make sure that message ids match */
404 if (mid
!= smb
->Mid
) {
405 cERROR(1, "Mids do not match. received=%u expected=%u",
410 /* if it's a response then accept */
411 if (smb
->Flags
& SMBFLG_RESPONSE
)
414 /* only one valid case where server sends us request */
415 if (smb
->Command
== SMB_COM_LOCKING_ANDX
)
418 cERROR(1, "Server sent request, not response. mid=%u", smb
->Mid
);
423 checkSMB(struct smb_hdr
*smb
, __u16 mid
, unsigned int length
)
425 __u32 len
= be32_to_cpu(smb
->smb_buf_length
);
426 __u32 clc_len
; /* calculated length */
427 cFYI(0, "checkSMB Length: 0x%x, smb_buf_length: 0x%x", length
, len
);
429 if (length
< 2 + sizeof(struct smb_hdr
)) {
430 if ((length
>= sizeof(struct smb_hdr
) - 1)
431 && (smb
->Status
.CifsError
!= 0)) {
433 /* some error cases do not return wct and bcc */
435 } else if ((length
== sizeof(struct smb_hdr
) + 1) &&
436 (smb
->WordCount
== 0)) {
437 char *tmp
= (char *)smb
;
438 /* Need to work around a bug in two servers here */
439 /* First, check if the part of bcc they sent was zero */
440 if (tmp
[sizeof(struct smb_hdr
)] == 0) {
441 /* some servers return only half of bcc
442 * on simple responses (wct, bcc both zero)
443 * in particular have seen this on
444 * ulogoffX and FindClose. This leaves
445 * one byte of bcc potentially unitialized
447 /* zero rest of bcc */
448 tmp
[sizeof(struct smb_hdr
)+1] = 0;
451 cERROR(1, "rcvd invalid byte count (bcc)");
453 cERROR(1, "Length less than smb header size");
457 if (len
> CIFSMaxBufSize
+ MAX_CIFS_HDR_SIZE
- 4) {
458 cERROR(1, "smb length greater than MaxBufSize, mid=%d",
463 if (check_smb_hdr(smb
, mid
))
465 clc_len
= smbCalcSize(smb
);
467 if (4 + len
!= length
) {
468 cERROR(1, "Length read does not match RFC1001 length %d",
473 if (4 + len
!= clc_len
) {
474 /* check if bcc wrapped around for large read responses */
475 if ((len
> 64 * 1024) && (len
> clc_len
)) {
476 /* check if lengths match mod 64K */
477 if (((4 + len
) & 0xFFFF) == (clc_len
& 0xFFFF))
478 return 0; /* bcc wrapped */
480 cFYI(1, "Calculated size %u vs length %u mismatch for mid=%u",
481 clc_len
, 4 + len
, smb
->Mid
);
483 if (4 + len
< clc_len
) {
484 cERROR(1, "RFC1001 size %u smaller than SMB for mid=%u",
487 } else if (len
> clc_len
+ 512) {
489 * Some servers (Windows XP in particular) send more
490 * data than the lengths in the SMB packet would
491 * indicate on certain calls (byte range locks and
492 * trans2 find first calls in particular). While the
493 * client can handle such a frame by ignoring the
494 * trailing data, we choose limit the amount of extra
497 cERROR(1, "RFC1001 size %u more than 512 bytes larger "
498 "than SMB for mid=%u", len
, smb
->Mid
);
506 is_valid_oplock_break(struct smb_hdr
*buf
, struct TCP_Server_Info
*srv
)
508 struct smb_com_lock_req
*pSMB
= (struct smb_com_lock_req
*)buf
;
509 struct list_head
*tmp
, *tmp1
, *tmp2
;
510 struct cifs_ses
*ses
;
511 struct cifs_tcon
*tcon
;
512 struct cifsInodeInfo
*pCifsInode
;
513 struct cifsFileInfo
*netfile
;
515 cFYI(1, "Checking for oplock break or dnotify response");
516 if ((pSMB
->hdr
.Command
== SMB_COM_NT_TRANSACT
) &&
517 (pSMB
->hdr
.Flags
& SMBFLG_RESPONSE
)) {
518 struct smb_com_transaction_change_notify_rsp
*pSMBr
=
519 (struct smb_com_transaction_change_notify_rsp
*)buf
;
520 struct file_notify_information
*pnotify
;
521 __u32 data_offset
= 0;
522 if (get_bcc(buf
) > sizeof(struct file_notify_information
)) {
523 data_offset
= le32_to_cpu(pSMBr
->DataOffset
);
525 pnotify
= (struct file_notify_information
*)
526 ((char *)&pSMBr
->hdr
.Protocol
+ data_offset
);
527 cFYI(1, "dnotify on %s Action: 0x%x",
528 pnotify
->FileName
, pnotify
->Action
);
529 /* cifs_dump_mem("Rcvd notify Data: ",buf,
530 sizeof(struct smb_hdr)+60); */
533 if (pSMBr
->hdr
.Status
.CifsError
) {
534 cFYI(1, "notify err 0x%d",
535 pSMBr
->hdr
.Status
.CifsError
);
540 if (pSMB
->hdr
.Command
!= SMB_COM_LOCKING_ANDX
)
542 if (pSMB
->hdr
.Flags
& SMBFLG_RESPONSE
) {
543 /* no sense logging error on invalid handle on oplock
544 break - harmless race between close request and oplock
545 break response is expected from time to time writing out
546 large dirty files cached on the client */
547 if ((NT_STATUS_INVALID_HANDLE
) ==
548 le32_to_cpu(pSMB
->hdr
.Status
.CifsError
)) {
549 cFYI(1, "invalid handle on oplock break");
551 } else if (ERRbadfid
==
552 le16_to_cpu(pSMB
->hdr
.Status
.DosError
.Error
)) {
555 return false; /* on valid oplock brk we get "request" */
558 if (pSMB
->hdr
.WordCount
!= 8)
561 cFYI(1, "oplock type 0x%d level 0x%d",
562 pSMB
->LockType
, pSMB
->OplockLevel
);
563 if (!(pSMB
->LockType
& LOCKING_ANDX_OPLOCK_RELEASE
))
566 /* look up tcon based on tid & uid */
567 spin_lock(&cifs_tcp_ses_lock
);
568 list_for_each(tmp
, &srv
->smb_ses_list
) {
569 ses
= list_entry(tmp
, struct cifs_ses
, smb_ses_list
);
570 list_for_each(tmp1
, &ses
->tcon_list
) {
571 tcon
= list_entry(tmp1
, struct cifs_tcon
, tcon_list
);
572 if (tcon
->tid
!= buf
->Tid
)
575 cifs_stats_inc(&tcon
->num_oplock_brks
);
576 spin_lock(&cifs_file_list_lock
);
577 list_for_each(tmp2
, &tcon
->openFileList
) {
578 netfile
= list_entry(tmp2
, struct cifsFileInfo
,
580 if (pSMB
->Fid
!= netfile
->netfid
)
583 cFYI(1, "file id match, oplock break");
584 pCifsInode
= CIFS_I(netfile
->dentry
->d_inode
);
586 cifs_set_oplock_level(pCifsInode
,
587 pSMB
->OplockLevel
? OPLOCK_READ
: 0);
589 * cifs_oplock_break_put() can't be called
590 * from here. Get reference after queueing
591 * succeeded. cifs_oplock_break() will
592 * synchronize using cifs_file_list_lock.
594 if (queue_work(system_nrt_wq
,
595 &netfile
->oplock_break
))
596 cifs_oplock_break_get(netfile
);
597 netfile
->oplock_break_cancelled
= false;
599 spin_unlock(&cifs_file_list_lock
);
600 spin_unlock(&cifs_tcp_ses_lock
);
603 spin_unlock(&cifs_file_list_lock
);
604 spin_unlock(&cifs_tcp_ses_lock
);
605 cFYI(1, "No matching file for oplock break");
609 spin_unlock(&cifs_tcp_ses_lock
);
610 cFYI(1, "Can not process oplock break for non-existent connection");
615 dump_smb(struct smb_hdr
*smb_buf
, int smb_buf_length
)
619 unsigned char *buffer
;
624 buffer
= (unsigned char *) smb_buf
;
625 for (i
= 0, j
= 0; i
< smb_buf_length
; i
++, j
++) {
627 /* have reached the beginning of line */
628 printk(KERN_DEBUG
"| ");
631 printk("%0#4x ", buffer
[i
]);
632 debug_line
[2 * j
] = ' ';
633 if (isprint(buffer
[i
]))
634 debug_line
[1 + (2 * j
)] = buffer
[i
];
636 debug_line
[1 + (2 * j
)] = '_';
639 /* reached end of line, time to print ascii */
641 printk(" | %s\n", debug_line
);
646 debug_line
[2 * j
] = ' ';
647 debug_line
[1 + (2 * j
)] = ' ';
649 printk(" | %s\n", debug_line
);
654 cifs_autodisable_serverino(struct cifs_sb_info
*cifs_sb
)
656 if (cifs_sb
->mnt_cifs_flags
& CIFS_MOUNT_SERVER_INUM
) {
657 cifs_sb
->mnt_cifs_flags
&= ~CIFS_MOUNT_SERVER_INUM
;
658 cERROR(1, "Autodisabling the use of server inode numbers on "
659 "%s. This server doesn't seem to support them "
660 "properly. Hardlinks will not be recognized on this "
661 "mount. Consider mounting with the \"noserverino\" "
662 "option to silence this message.",
663 cifs_sb_master_tcon(cifs_sb
)->treeName
);
667 void cifs_set_oplock_level(struct cifsInodeInfo
*cinode
, __u32 oplock
)
671 if (oplock
== OPLOCK_EXCLUSIVE
) {
672 cinode
->clientCanCacheAll
= true;
673 cinode
->clientCanCacheRead
= true;
674 cFYI(1, "Exclusive Oplock granted on inode %p",
676 } else if (oplock
== OPLOCK_READ
) {
677 cinode
->clientCanCacheAll
= false;
678 cinode
->clientCanCacheRead
= true;
679 cFYI(1, "Level II Oplock granted on inode %p",
682 cinode
->clientCanCacheAll
= false;
683 cinode
->clientCanCacheRead
= false;