4 * Copyright (C) International Business Machines Corp., 2002,2007
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;
35 extern struct task_struct *oplockThread;
37 /* The xid serves as a useful identifier for each incoming vfs request,
38 in a similar way to the mid which is useful to track each sent smb,
39 and CurrentXid can also provide a running counter (although it
40 will eventually wrap past zero) of the total vfs operations handled
41 since the cifs fs was mounted */
48 spin_lock(&GlobalMid_Lock);
49 GlobalTotalActiveXid++;
51 /* keep high water mark for number of simultaneous ops in filesystem */
52 if (GlobalTotalActiveXid > GlobalMaxActiveXid)
53 GlobalMaxActiveXid = GlobalTotalActiveXid;
54 if (GlobalTotalActiveXid > 65000)
55 cFYI(1, ("warning: more than 65000 requests active"));
56 xid = GlobalCurrentXid++;
57 spin_unlock(&GlobalMid_Lock);
62 _FreeXid(unsigned int xid)
64 spin_lock(&GlobalMid_Lock);
65 /* if (GlobalTotalActiveXid == 0)
67 GlobalTotalActiveXid--;
68 spin_unlock(&GlobalMid_Lock);
74 struct cifsSesInfo *ret_buf;
76 ret_buf = kzalloc(sizeof (struct cifsSesInfo), GFP_KERNEL);
78 write_lock(&GlobalSMBSeslock);
79 atomic_inc(&sesInfoAllocCount);
80 ret_buf->status = CifsNew;
81 list_add(&ret_buf->cifsSessionList, &GlobalSMBSessionList);
82 init_MUTEX(&ret_buf->sesSem);
83 write_unlock(&GlobalSMBSeslock);
89 sesInfoFree(struct cifsSesInfo *buf_to_free)
91 if (buf_to_free == NULL) {
92 cFYI(1, ("Null buffer passed to sesInfoFree"));
96 write_lock(&GlobalSMBSeslock);
97 atomic_dec(&sesInfoAllocCount);
98 list_del(&buf_to_free->cifsSessionList);
99 write_unlock(&GlobalSMBSeslock);
100 kfree(buf_to_free->serverOS);
101 kfree(buf_to_free->serverDomain);
102 kfree(buf_to_free->serverNOS);
103 kfree(buf_to_free->password);
104 kfree(buf_to_free->domainName);
108 struct cifsTconInfo *
111 struct cifsTconInfo *ret_buf;
112 ret_buf = kzalloc(sizeof (struct cifsTconInfo), GFP_KERNEL);
114 write_lock(&GlobalSMBSeslock);
115 atomic_inc(&tconInfoAllocCount);
116 list_add(&ret_buf->cifsConnectionList,
117 &GlobalTreeConnectionList);
118 ret_buf->tidStatus = CifsNew;
119 INIT_LIST_HEAD(&ret_buf->openFileList);
120 init_MUTEX(&ret_buf->tconSem);
121 #ifdef CONFIG_CIFS_STATS
122 spin_lock_init(&ret_buf->stat_lock);
124 write_unlock(&GlobalSMBSeslock);
130 tconInfoFree(struct cifsTconInfo *buf_to_free)
132 if (buf_to_free == NULL) {
133 cFYI(1, ("Null buffer passed to tconInfoFree"));
136 write_lock(&GlobalSMBSeslock);
137 atomic_dec(&tconInfoAllocCount);
138 list_del(&buf_to_free->cifsConnectionList);
139 write_unlock(&GlobalSMBSeslock);
140 kfree(buf_to_free->nativeFileSystem);
147 struct smb_hdr *ret_buf = NULL;
149 /* We could use negotiated size instead of max_msgsize -
150 but it may be more efficient to always alloc same size
151 albeit slightly larger than necessary and maxbuffersize
152 defaults to this and can not be bigger */
153 ret_buf = (struct smb_hdr *) mempool_alloc(cifs_req_poolp,
154 GFP_KERNEL | GFP_NOFS);
156 /* clear the first few header bytes */
157 /* for most paths, more is cleared in header_assemble */
159 memset(ret_buf, 0, sizeof(struct smb_hdr) + 3);
160 atomic_inc(&bufAllocCount);
161 #ifdef CONFIG_CIFS_STATS2
162 atomic_inc(&totBufAllocCount);
163 #endif /* CONFIG_CIFS_STATS2 */
170 cifs_buf_release(void *buf_to_free)
173 if (buf_to_free == NULL) {
174 /* cFYI(1, ("Null buffer passed to cifs_buf_release"));*/
177 mempool_free(buf_to_free, cifs_req_poolp);
179 atomic_dec(&bufAllocCount);
184 cifs_small_buf_get(void)
186 struct smb_hdr *ret_buf = NULL;
188 /* We could use negotiated size instead of max_msgsize -
189 but it may be more efficient to always alloc same size
190 albeit slightly larger than necessary and maxbuffersize
191 defaults to this and can not be bigger */
192 ret_buf = (struct smb_hdr *) mempool_alloc(cifs_sm_req_poolp,
193 GFP_KERNEL | GFP_NOFS);
195 /* No need to clear memory here, cleared in header assemble */
196 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
197 atomic_inc(&smBufAllocCount);
198 #ifdef CONFIG_CIFS_STATS2
199 atomic_inc(&totSmBufAllocCount);
200 #endif /* CONFIG_CIFS_STATS2 */
207 cifs_small_buf_release(void *buf_to_free)
210 if (buf_to_free == NULL) {
211 cFYI(1, ("Null buffer passed to cifs_small_buf_release"));
214 mempool_free(buf_to_free, cifs_sm_req_poolp);
216 atomic_dec(&smBufAllocCount);
221 Find a free multiplex id (SMB mid). Otherwise there could be
222 mid collisions which might cause problems, demultiplexing the
223 wrong response to this request. Multiplex ids could collide if
224 one of a series requests takes much longer than the others, or
225 if a very large number of long lived requests (byte range
226 locks or FindNotify requests) are pending. No more than
227 64K-1 requests can be outstanding at one time. If no
228 mids are available, return zero. A future optimization
229 could make the combination of mids and uid the key we use
230 to demultiplex on (rather than mid alone).
231 In addition to the above check, the cifs demultiplex
232 code already used the command code as a secondary
233 check of the frame and if signing is negotiated the
234 response would be discarded if the mid were the same
235 but the signature was wrong. Since the mid is not put in the
236 pending queue until later (when it is about to be dispatched)
237 we do have to limit the number of outstanding requests
238 to somewhat less than 64K-1 although it is hard to imagine
239 so many threads being in the vfs at one time.
241 __u16 GetNextMid(struct TCP_Server_Info *server)
250 spin_lock(&GlobalMid_Lock);
251 last_mid = server->CurrentMid; /* we do not want to loop forever */
252 server->CurrentMid++;
253 /* This nested loop looks more expensive than it is.
254 In practice the list of pending requests is short,
255 fewer than 50, and the mids are likely to be unique
256 on the first pass through the loop unless some request
257 takes longer than the 64 thousand requests before it
258 (and it would also have to have been a request that
260 while (server->CurrentMid != last_mid) {
261 struct list_head *tmp;
262 struct mid_q_entry *mid_entry;
265 if (server->CurrentMid == 0)
266 server->CurrentMid++;
268 list_for_each(tmp, &server->pending_mid_q) {
269 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
271 if ((mid_entry->mid == server->CurrentMid) &&
272 (mid_entry->midState == MID_REQUEST_SUBMITTED)) {
273 /* This mid is in use, try a different one */
278 if (collision == 0) {
279 mid = server->CurrentMid;
282 server->CurrentMid++;
284 spin_unlock(&GlobalMid_Lock);
288 /* NB: MID can not be set if treeCon not passed in, in that
289 case it is responsbility of caller to set the mid */
291 header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
292 const struct cifsTconInfo *treeCon, int word_count
293 /* length of fixed section (word count) in two byte units */)
295 struct list_head *temp_item;
296 struct cifsSesInfo *ses;
297 char *temp = (char *) buffer;
299 memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
301 buffer->smb_buf_length =
302 (2 * word_count) + sizeof (struct smb_hdr) -
303 4 /* RFC 1001 length field does not count */ +
304 2 /* for bcc field itself */ ;
305 /* Note that this is the only network field that has to be converted
306 to big endian and it is done just before we send it */
308 buffer->Protocol[0] = 0xFF;
309 buffer->Protocol[1] = 'S';
310 buffer->Protocol[2] = 'M';
311 buffer->Protocol[3] = 'B';
312 buffer->Command = smb_command;
313 buffer->Flags = 0x00; /* case sensitive */
314 buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
315 buffer->Pid = cpu_to_le16((__u16)current->tgid);
316 buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
317 spin_lock(&GlobalMid_Lock);
318 spin_unlock(&GlobalMid_Lock);
320 buffer->Tid = treeCon->tid;
322 if (treeCon->ses->capabilities & CAP_UNICODE)
323 buffer->Flags2 |= SMBFLG2_UNICODE;
324 if (treeCon->ses->capabilities & CAP_STATUS32) {
325 buffer->Flags2 |= SMBFLG2_ERR_STATUS;
327 /* Uid is not converted */
328 buffer->Uid = treeCon->ses->Suid;
329 buffer->Mid = GetNextMid(treeCon->ses->server);
330 if (multiuser_mount != 0) {
331 /* For the multiuser case, there are few obvious technically */
332 /* possible mechanisms to match the local linux user (uid) */
333 /* to a valid remote smb user (smb_uid): */
334 /* 1) Query Winbind (or other local pam/nss daemon */
335 /* for userid/password/logon_domain or credential */
336 /* 2) Query Winbind for uid to sid to username mapping */
337 /* and see if we have a matching password for existing*/
338 /* session for that user perhas getting password by */
339 /* adding a new pam_cifs module that stores passwords */
340 /* so that the cifs vfs can get at that for all logged*/
342 /* 3) (Which is the mechanism we have chosen) */
343 /* Search through sessions to the same server for a */
344 /* a match on the uid that was passed in on mount */
345 /* with the current processes uid (or euid?) and use */
346 /* that smb uid. If no existing smb session for */
347 /* that uid found, use the default smb session ie */
348 /* the smb session for the volume mounted which is */
349 /* the same as would be used if the multiuser mount */
350 /* flag were disabled. */
352 /* BB Add support for establishing new tCon and SMB Session */
353 /* with userid/password pairs found on the smb session */
354 /* for other target tcp/ip addresses BB */
355 if (current->fsuid != treeCon->ses->linux_uid) {
356 cFYI(1, ("Multiuser mode and UID "
357 "did not match tcon uid"));
358 read_lock(&GlobalSMBSeslock);
359 list_for_each(temp_item, &GlobalSMBSessionList) {
360 ses = list_entry(temp_item, struct cifsSesInfo, cifsSessionList);
361 if (ses->linux_uid == current->fsuid) {
362 if (ses->server == treeCon->ses->server) {
363 cFYI(1, ("found matching uid substitute right smb_uid"));
364 buffer->Uid = ses->Suid;
367 /* BB eventually call cifs_setup_session here */
368 cFYI(1, ("local UID found but no smb sess with this server exists"));
372 read_unlock(&GlobalSMBSeslock);
376 if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
377 buffer->Flags2 |= SMBFLG2_DFS;
379 buffer->Flags |= SMBFLG_CASELESS;
380 if ((treeCon->ses) && (treeCon->ses->server))
381 if (treeCon->ses->server->secMode &
382 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
383 buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
386 /* endian conversion of flags is now done just before sending */
387 buffer->WordCount = (char) word_count;
392 checkSMBhdr(struct smb_hdr *smb, __u16 mid)
394 /* Make sure that this really is an SMB, that it is a response,
395 and that the message ids match */
396 if ((*(__le32 *) smb->Protocol == cpu_to_le32(0x424d53ff)) &&
398 if (smb->Flags & SMBFLG_RESPONSE)
401 /* only one valid case where server sends us request */
402 if (smb->Command == SMB_COM_LOCKING_ANDX)
405 cERROR(1, ("Received Request not response"));
407 } else { /* bad signature or mid */
408 if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff))
410 ("Bad protocol string signature header %x",
411 *(unsigned int *) smb->Protocol));
413 cERROR(1, ("Mids do not match"));
415 cERROR(1, ("bad smb detected. The Mid=%d", smb->Mid));
420 checkSMB(struct smb_hdr *smb, __u16 mid, unsigned int length)
422 __u32 len = smb->smb_buf_length;
423 __u32 clc_len; /* calculated length */
424 cFYI(0, ("checkSMB Length: 0x%x, smb_buf_length: 0x%x", length, len));
426 if (length < 2 + sizeof (struct smb_hdr)) {
427 if ((length >= sizeof (struct smb_hdr) - 1)
428 && (smb->Status.CifsError != 0)) {
430 /* some error cases do not return wct and bcc */
432 } else if ((length == sizeof(struct smb_hdr) + 1) &&
433 (smb->WordCount == 0)) {
434 char *tmp = (char *)smb;
435 /* Need to work around a bug in two servers here */
436 /* First, check if the part of bcc they sent was zero */
437 if (tmp[sizeof(struct smb_hdr)] == 0) {
438 /* some servers return only half of bcc
439 * on simple responses (wct, bcc both zero)
440 * in particular have seen this on
441 * ulogoffX and FindClose. This leaves
442 * one byte of bcc potentially unitialized
444 /* zero rest of bcc */
445 tmp[sizeof(struct smb_hdr)+1] = 0;
448 cERROR(1, ("rcvd invalid byte count (bcc)"));
450 cERROR(1, ("Length less than smb header size"));
454 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
455 cERROR(1, ("smb length greater than MaxBufSize, mid=%d",
460 if (checkSMBhdr(smb, mid))
462 clc_len = smbCalcSize_LE(smb);
464 if (4 + len != length) {
465 cERROR(1, ("Length read does not match RFC1001 length %d",
470 if (4 + len != clc_len) {
471 /* check if bcc wrapped around for large read responses */
472 if ((len > 64 * 1024) && (len > clc_len)) {
473 /* check if lengths match mod 64K */
474 if (((4 + len) & 0xFFFF) == (clc_len & 0xFFFF))
475 return 0; /* bcc wrapped */
477 cFYI(1, ("Calculated size %d vs length %d mismatch for mid %d",
478 clc_len, 4 + len, smb->Mid));
479 /* Windows XP can return a few bytes too much, presumably
480 an illegal pad, at the end of byte range lock responses
481 so we allow for that three byte pad, as long as actual
482 received length is as long or longer than calculated length */
483 /* We have now had to extend this more, since there is a
484 case in which it needs to be bigger still to handle a
485 malformed response to transact2 findfirst from WinXP when
486 access denied is returned and thus bcc and wct are zero
487 but server says length is 0x21 bytes too long as if the server
488 forget to reset the smb rfc1001 length when it reset the
489 wct and bcc to minimum size and drop the t2 parms and data */
490 if ((4+len > clc_len) && (len <= clc_len + 512))
493 cERROR(1, ("RFC1001 size %d bigger than SMB for Mid=%d",
501 is_valid_oplock_break(struct smb_hdr *buf, struct TCP_Server_Info *srv)
503 struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;
504 struct list_head *tmp;
505 struct list_head *tmp1;
506 struct cifsTconInfo *tcon;
507 struct cifsFileInfo *netfile;
509 cFYI(1, ("Checking for oplock break or dnotify response"));
510 if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
511 (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {
512 struct smb_com_transaction_change_notify_rsp *pSMBr =
513 (struct smb_com_transaction_change_notify_rsp *)buf;
514 struct file_notify_information *pnotify;
515 __u32 data_offset = 0;
516 if (pSMBr->ByteCount > sizeof(struct file_notify_information)) {
517 data_offset = le32_to_cpu(pSMBr->DataOffset);
519 pnotify = (struct file_notify_information *)
520 ((char *)&pSMBr->hdr.Protocol + data_offset);
521 cFYI(1, ("dnotify on %s Action: 0x%x",
523 pnotify->Action)); /* BB removeme BB */
524 /* cifs_dump_mem("Rcvd notify Data: ",buf,
525 sizeof(struct smb_hdr)+60); */
528 if (pSMBr->hdr.Status.CifsError) {
529 cFYI(1, ("notify err 0x%d",
530 pSMBr->hdr.Status.CifsError));
535 if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
537 if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {
538 /* no sense logging error on invalid handle on oplock
539 break - harmless race between close request and oplock
540 break response is expected from time to time writing out
541 large dirty files cached on the client */
542 if ((NT_STATUS_INVALID_HANDLE) ==
543 le32_to_cpu(pSMB->hdr.Status.CifsError)) {
544 cFYI(1, ("invalid handle on oplock break"));
546 } else if (ERRbadfid ==
547 le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
550 return FALSE; /* on valid oplock brk we get "request" */
553 if (pSMB->hdr.WordCount != 8)
556 cFYI(1, ("oplock type 0x%d level 0x%d",
557 pSMB->LockType, pSMB->OplockLevel));
558 if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
561 /* look up tcon based on tid & uid */
562 read_lock(&GlobalSMBSeslock);
563 list_for_each(tmp, &GlobalTreeConnectionList) {
564 tcon = list_entry(tmp, struct cifsTconInfo, cifsConnectionList);
565 if ((tcon->tid == buf->Tid) && (srv == tcon->ses->server)) {
566 cifs_stats_inc(&tcon->num_oplock_brks);
567 list_for_each(tmp1, &tcon->openFileList) {
568 netfile = list_entry(tmp1, struct cifsFileInfo,
570 if (pSMB->Fid == netfile->netfid) {
571 struct cifsInodeInfo *pCifsInode;
572 read_unlock(&GlobalSMBSeslock);
574 ("file id match, oplock break"));
576 CIFS_I(netfile->pInode);
577 pCifsInode->clientCanCacheAll = FALSE;
578 if (pSMB->OplockLevel == 0)
579 pCifsInode->clientCanCacheRead
581 pCifsInode->oplockPending = TRUE;
582 AllocOplockQEntry(netfile->pInode,
586 ("about to wake up oplock thread"));
588 wake_up_process(oplockThread);
592 read_unlock(&GlobalSMBSeslock);
593 cFYI(1, ("No matching file for oplock break"));
597 read_unlock(&GlobalSMBSeslock);
598 cFYI(1, ("Can not process oplock break for non-existent connection"));
603 dump_smb(struct smb_hdr *smb_buf, int smb_buf_length)
607 unsigned char *buffer;
612 buffer = (unsigned char *) smb_buf;
613 for (i = 0, j = 0; i < smb_buf_length; i++, j++) {
614 if (i % 8 == 0) { /* have reached the beginning of line */
615 printk(KERN_DEBUG "| ");
618 printk("%0#4x ", buffer[i]);
619 debug_line[2 * j] = ' ';
620 if (isprint(buffer[i]))
621 debug_line[1 + (2 * j)] = buffer[i];
623 debug_line[1 + (2 * j)] = '_';
625 if (i % 8 == 7) { /* reached end of line, time to print ascii */
627 printk(" | %s\n", debug_line);
632 debug_line[2 * j] = ' ';
633 debug_line[1 + (2 * j)] = ' ';
635 printk( " | %s\n", debug_line);
639 /* Windows maps these to the user defined 16 bit Unicode range since they are
640 reserved symbols (along with \ and /), otherwise illegal to store
641 in filenames in NTFS */
642 #define UNI_ASTERIK (__u16) ('*' + 0xF000)
643 #define UNI_QUESTION (__u16) ('?' + 0xF000)
644 #define UNI_COLON (__u16) (':' + 0xF000)
645 #define UNI_GRTRTHAN (__u16) ('>' + 0xF000)
646 #define UNI_LESSTHAN (__u16) ('<' + 0xF000)
647 #define UNI_PIPE (__u16) ('|' + 0xF000)
648 #define UNI_SLASH (__u16) ('\\' + 0xF000)
650 /* Convert 16 bit Unicode pathname from wire format to string in current code
651 page. Conversion may involve remapping up the seven characters that are
652 only legal in POSIX-like OS (if they are present in the string). Path
653 names are little endian 16 bit Unicode on the wire */
655 cifs_convertUCSpath(char *target, const __le16 *source, int maxlen,
656 const struct nls_table *cp)
661 for (i = 0, j = 0; i < maxlen; i++) {
662 src_char = le16_to_cpu(source[i]);
665 goto cUCS_out; /* BB check this BB */
675 /* BB We can not handle remapping slash until
676 all the calls to build_path_from_dentry
677 are modified, as they use slash as separator BB */
691 len = cp->uni2char(src_char, &target[j],
692 NLS_MAX_CHARSET_SIZE);
701 /* make sure we do not overrun callers allocated temp buffer */
702 if (j >= (2 * NAME_MAX))
710 /* Convert 16 bit Unicode pathname to wire format from string in current code
711 page. Conversion may involve remapping up the seven characters that are
712 only legal in POSIX-like OS (if they are present in the string). Path
713 names are little endian 16 bit Unicode on the wire */
715 cifsConvertToUCS(__le16 *target, const char *source, int maxlen,
716 const struct nls_table *cp, int mapChars)
719 int len_remaining = maxlen;
724 return cifs_strtoUCS(target, source, PATH_MAX, cp);
726 for (i = 0, j = 0; i < maxlen; j++) {
727 src_char = source[i];
733 target[j] = cpu_to_le16(UNI_COLON);
736 target[j] = cpu_to_le16(UNI_ASTERIK);
739 target[j] = cpu_to_le16(UNI_QUESTION);
742 target[j] = cpu_to_le16(UNI_LESSTHAN);
745 target[j] = cpu_to_le16(UNI_GRTRTHAN);
748 target[j] = cpu_to_le16(UNI_PIPE);
750 /* BB We can not handle remapping slash until
751 all the calls to build_path_from_dentry
752 are modified, as they use slash as separator BB */
754 target[j] = cpu_to_le16(UNI_SLASH);
757 charlen = cp->char2uni(source+i,
758 len_remaining, &temp);
759 /* if no match, use question mark, which
760 at least in some cases servers as wild card */
762 target[j] = cpu_to_le16(0x003f);
765 target[j] = cpu_to_le16(temp);
766 len_remaining -= charlen;
767 /* character may take more than one byte in the
768 the source string, but will take exactly two
769 bytes in the target string */
773 i++; /* move to next char in source string */