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;
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)
172 if (buf_to_free == NULL) {
173 /* cFYI(1, ("Null buffer passed to cifs_buf_release"));*/
176 mempool_free(buf_to_free, cifs_req_poolp);
178 atomic_dec(&bufAllocCount);
183 cifs_small_buf_get(void)
185 struct smb_hdr *ret_buf = NULL;
187 /* We could use negotiated size instead of max_msgsize -
188 but it may be more efficient to always alloc same size
189 albeit slightly larger than necessary and maxbuffersize
190 defaults to this and can not be bigger */
191 ret_buf = (struct smb_hdr *) mempool_alloc(cifs_sm_req_poolp,
192 GFP_KERNEL | GFP_NOFS);
194 /* No need to clear memory here, cleared in header assemble */
195 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
196 atomic_inc(&smBufAllocCount);
197 #ifdef CONFIG_CIFS_STATS2
198 atomic_inc(&totSmBufAllocCount);
199 #endif /* CONFIG_CIFS_STATS2 */
206 cifs_small_buf_release(void *buf_to_free)
209 if (buf_to_free == NULL) {
210 cFYI(1, ("Null buffer passed to cifs_small_buf_release"));
213 mempool_free(buf_to_free, cifs_sm_req_poolp);
215 atomic_dec(&smBufAllocCount);
220 Find a free multiplex id (SMB mid). Otherwise there could be
221 mid collisions which might cause problems, demultiplexing the
222 wrong response to this request. Multiplex ids could collide if
223 one of a series requests takes much longer than the others, or
224 if a very large number of long lived requests (byte range
225 locks or FindNotify requests) are pending. No more than
226 64K-1 requests can be outstanding at one time. If no
227 mids are available, return zero. A future optimization
228 could make the combination of mids and uid the key we use
229 to demultiplex on (rather than mid alone).
230 In addition to the above check, the cifs demultiplex
231 code already used the command code as a secondary
232 check of the frame and if signing is negotiated the
233 response would be discarded if the mid were the same
234 but the signature was wrong. Since the mid is not put in the
235 pending queue until later (when it is about to be dispatched)
236 we do have to limit the number of outstanding requests
237 to somewhat less than 64K-1 although it is hard to imagine
238 so many threads being in the vfs at one time.
240 __u16 GetNextMid(struct TCP_Server_Info *server)
249 spin_lock(&GlobalMid_Lock);
250 last_mid = server->CurrentMid; /* we do not want to loop forever */
251 server->CurrentMid++;
252 /* This nested loop looks more expensive than it is.
253 In practice the list of pending requests is short,
254 fewer than 50, and the mids are likely to be unique
255 on the first pass through the loop unless some request
256 takes longer than the 64 thousand requests before it
257 (and it would also have to have been a request that
259 while (server->CurrentMid != last_mid) {
260 struct list_head *tmp;
261 struct mid_q_entry *mid_entry;
264 if (server->CurrentMid == 0)
265 server->CurrentMid++;
267 list_for_each(tmp, &server->pending_mid_q) {
268 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
270 if ((mid_entry->mid == server->CurrentMid) &&
271 (mid_entry->midState == MID_REQUEST_SUBMITTED)) {
272 /* This mid is in use, try a different one */
277 if (collision == 0) {
278 mid = server->CurrentMid;
281 server->CurrentMid++;
283 spin_unlock(&GlobalMid_Lock);
287 /* NB: MID can not be set if treeCon not passed in, in that
288 case it is responsbility of caller to set the mid */
290 header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
291 const struct cifsTconInfo *treeCon, int word_count
292 /* length of fixed section (word count) in two byte units */)
294 struct list_head *temp_item;
295 struct cifsSesInfo *ses;
296 char *temp = (char *) buffer;
298 memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
300 buffer->smb_buf_length =
301 (2 * word_count) + sizeof(struct smb_hdr) -
302 4 /* RFC 1001 length field does not count */ +
303 2 /* for bcc field itself */ ;
304 /* Note that this is the only network field that has to be converted
305 to big endian and it is done just before we send it */
307 buffer->Protocol[0] = 0xFF;
308 buffer->Protocol[1] = 'S';
309 buffer->Protocol[2] = 'M';
310 buffer->Protocol[3] = 'B';
311 buffer->Command = smb_command;
312 buffer->Flags = 0x00; /* case sensitive */
313 buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
314 buffer->Pid = cpu_to_le16((__u16)current->tgid);
315 buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
316 spin_lock(&GlobalMid_Lock);
317 spin_unlock(&GlobalMid_Lock);
319 buffer->Tid = treeCon->tid;
321 if (treeCon->ses->capabilities & CAP_UNICODE)
322 buffer->Flags2 |= SMBFLG2_UNICODE;
323 if (treeCon->ses->capabilities & CAP_STATUS32)
324 buffer->Flags2 |= SMBFLG2_ERR_STATUS;
326 /* Uid is not converted */
327 buffer->Uid = treeCon->ses->Suid;
328 buffer->Mid = GetNextMid(treeCon->ses->server);
329 if (multiuser_mount != 0) {
330 /* For the multiuser case, there are few obvious technically */
331 /* possible mechanisms to match the local linux user (uid) */
332 /* to a valid remote smb user (smb_uid): */
333 /* 1) Query Winbind (or other local pam/nss daemon */
334 /* for userid/password/logon_domain or credential */
335 /* 2) Query Winbind for uid to sid to username mapping */
336 /* and see if we have a matching password for existing*/
337 /* session for that user perhas getting password by */
338 /* adding a new pam_cifs module that stores passwords */
339 /* so that the cifs vfs can get at that for all logged*/
341 /* 3) (Which is the mechanism we have chosen) */
342 /* Search through sessions to the same server for a */
343 /* a match on the uid that was passed in on mount */
344 /* with the current processes uid (or euid?) and use */
345 /* that smb uid. If no existing smb session for */
346 /* that uid found, use the default smb session ie */
347 /* the smb session for the volume mounted which is */
348 /* the same as would be used if the multiuser mount */
349 /* flag were disabled. */
351 /* BB Add support for establishing new tCon and SMB Session */
352 /* with userid/password pairs found on the smb session */
353 /* for other target tcp/ip addresses BB */
354 if (current->fsuid != treeCon->ses->linux_uid) {
355 cFYI(1, ("Multiuser mode and UID "
356 "did not match tcon uid"));
357 read_lock(&GlobalSMBSeslock);
358 list_for_each(temp_item, &GlobalSMBSessionList) {
359 ses = list_entry(temp_item, struct cifsSesInfo, cifsSessionList);
360 if (ses->linux_uid == current->fsuid) {
361 if (ses->server == treeCon->ses->server) {
362 cFYI(1, ("found matching uid substitute right smb_uid"));
363 buffer->Uid = ses->Suid;
366 /* BB eventually call cifs_setup_session here */
367 cFYI(1, ("local UID found but no smb sess with this server exists"));
371 read_unlock(&GlobalSMBSeslock);
375 if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
376 buffer->Flags2 |= SMBFLG2_DFS;
378 buffer->Flags |= SMBFLG_CASELESS;
379 if ((treeCon->ses) && (treeCon->ses->server))
380 if (treeCon->ses->server->secMode &
381 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
382 buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
385 /* endian conversion of flags is now done just before sending */
386 buffer->WordCount = (char) word_count;
391 checkSMBhdr(struct smb_hdr *smb, __u16 mid)
393 /* Make sure that this really is an SMB, that it is a response,
394 and that the message ids match */
395 if ((*(__le32 *) smb->Protocol == cpu_to_le32(0x424d53ff)) &&
397 if (smb->Flags & SMBFLG_RESPONSE)
400 /* only one valid case where server sends us request */
401 if (smb->Command == SMB_COM_LOCKING_ANDX)
404 cERROR(1, ("Received Request not response"));
406 } else { /* bad signature or mid */
407 if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff))
409 ("Bad protocol string signature header %x",
410 *(unsigned int *) smb->Protocol));
412 cERROR(1, ("Mids do not match"));
414 cERROR(1, ("bad smb detected. The Mid=%d", smb->Mid));
419 checkSMB(struct smb_hdr *smb, __u16 mid, unsigned int length)
421 __u32 len = smb->smb_buf_length;
422 __u32 clc_len; /* calculated length */
423 cFYI(0, ("checkSMB Length: 0x%x, smb_buf_length: 0x%x", length, len));
425 if (length < 2 + sizeof(struct smb_hdr)) {
426 if ((length >= sizeof(struct smb_hdr) - 1)
427 && (smb->Status.CifsError != 0)) {
429 /* some error cases do not return wct and bcc */
431 } else if ((length == sizeof(struct smb_hdr) + 1) &&
432 (smb->WordCount == 0)) {
433 char *tmp = (char *)smb;
434 /* Need to work around a bug in two servers here */
435 /* First, check if the part of bcc they sent was zero */
436 if (tmp[sizeof(struct smb_hdr)] == 0) {
437 /* some servers return only half of bcc
438 * on simple responses (wct, bcc both zero)
439 * in particular have seen this on
440 * ulogoffX and FindClose. This leaves
441 * one byte of bcc potentially unitialized
443 /* zero rest of bcc */
444 tmp[sizeof(struct smb_hdr)+1] = 0;
447 cERROR(1, ("rcvd invalid byte count (bcc)"));
449 cERROR(1, ("Length less than smb header size"));
453 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
454 cERROR(1, ("smb length greater than MaxBufSize, mid=%d",
459 if (checkSMBhdr(smb, mid))
461 clc_len = smbCalcSize_LE(smb);
463 if (4 + len != length) {
464 cERROR(1, ("Length read does not match RFC1001 length %d",
469 if (4 + len != clc_len) {
470 /* check if bcc wrapped around for large read responses */
471 if ((len > 64 * 1024) && (len > clc_len)) {
472 /* check if lengths match mod 64K */
473 if (((4 + len) & 0xFFFF) == (clc_len & 0xFFFF))
474 return 0; /* bcc wrapped */
476 cFYI(1, ("Calculated size %d vs length %d mismatch for mid %d",
477 clc_len, 4 + len, smb->Mid));
478 /* Windows XP can return a few bytes too much, presumably
479 an illegal pad, at the end of byte range lock responses
480 so we allow for that three byte pad, as long as actual
481 received length is as long or longer than calculated length */
482 /* We have now had to extend this more, since there is a
483 case in which it needs to be bigger still to handle a
484 malformed response to transact2 findfirst from WinXP when
485 access denied is returned and thus bcc and wct are zero
486 but server says length is 0x21 bytes too long as if the server
487 forget to reset the smb rfc1001 length when it reset the
488 wct and bcc to minimum size and drop the t2 parms and data */
489 if ((4+len > clc_len) && (len <= clc_len + 512))
492 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",
522 pnotify->FileName, pnotify->Action));
523 /* cifs_dump_mem("Rcvd notify Data: ",buf,
524 sizeof(struct smb_hdr)+60); */
527 if (pSMBr->hdr.Status.CifsError) {
528 cFYI(1, ("notify err 0x%d",
529 pSMBr->hdr.Status.CifsError));
534 if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
536 if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {
537 /* no sense logging error on invalid handle on oplock
538 break - harmless race between close request and oplock
539 break response is expected from time to time writing out
540 large dirty files cached on the client */
541 if ((NT_STATUS_INVALID_HANDLE) ==
542 le32_to_cpu(pSMB->hdr.Status.CifsError)) {
543 cFYI(1, ("invalid handle on oplock break"));
545 } else if (ERRbadfid ==
546 le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
549 return false; /* on valid oplock brk we get "request" */
552 if (pSMB->hdr.WordCount != 8)
555 cFYI(1, ("oplock type 0x%d level 0x%d",
556 pSMB->LockType, pSMB->OplockLevel));
557 if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
560 /* look up tcon based on tid & uid */
561 read_lock(&GlobalSMBSeslock);
562 list_for_each(tmp, &GlobalTreeConnectionList) {
563 tcon = list_entry(tmp, struct cifsTconInfo, cifsConnectionList);
564 if ((tcon->tid == buf->Tid) && (srv == tcon->ses->server)) {
565 cifs_stats_inc(&tcon->num_oplock_brks);
566 list_for_each(tmp1, &tcon->openFileList) {
567 netfile = list_entry(tmp1, struct cifsFileInfo,
569 if (pSMB->Fid == netfile->netfid) {
570 struct cifsInodeInfo *pCifsInode;
571 read_unlock(&GlobalSMBSeslock);
573 ("file id match, oplock break"));
575 CIFS_I(netfile->pInode);
576 pCifsInode->clientCanCacheAll = false;
577 if (pSMB->OplockLevel == 0)
578 pCifsInode->clientCanCacheRead
580 pCifsInode->oplockPending = true;
581 AllocOplockQEntry(netfile->pInode,
585 ("about to wake up oplock thread"));
587 wake_up_process(oplockThread);
591 read_unlock(&GlobalSMBSeslock);
592 cFYI(1, ("No matching file for oplock break"));
596 read_unlock(&GlobalSMBSeslock);
597 cFYI(1, ("Can not process oplock break for non-existent connection"));
602 dump_smb(struct smb_hdr *smb_buf, int smb_buf_length)
606 unsigned char *buffer;
611 buffer = (unsigned char *) smb_buf;
612 for (i = 0, j = 0; i < smb_buf_length; i++, j++) {
614 /* 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)] = '_';
626 /* reached end of line, time to print ascii */
628 printk(" | %s\n", debug_line);
633 debug_line[2 * j] = ' ';
634 debug_line[1 + (2 * j)] = ' ';
636 printk(" | %s\n", debug_line);
640 /* Windows maps these to the user defined 16 bit Unicode range since they are
641 reserved symbols (along with \ and /), otherwise illegal to store
642 in filenames in NTFS */
643 #define UNI_ASTERIK (__u16) ('*' + 0xF000)
644 #define UNI_QUESTION (__u16) ('?' + 0xF000)
645 #define UNI_COLON (__u16) (':' + 0xF000)
646 #define UNI_GRTRTHAN (__u16) ('>' + 0xF000)
647 #define UNI_LESSTHAN (__u16) ('<' + 0xF000)
648 #define UNI_PIPE (__u16) ('|' + 0xF000)
649 #define UNI_SLASH (__u16) ('\\' + 0xF000)
651 /* Convert 16 bit Unicode pathname from wire format to string in current code
652 page. Conversion may involve remapping up the seven characters that are
653 only legal in POSIX-like OS (if they are present in the string). Path
654 names are little endian 16 bit Unicode on the wire */
656 cifs_convertUCSpath(char *target, const __le16 *source, int maxlen,
657 const struct nls_table *cp)
662 for (i = 0, j = 0; i < maxlen; i++) {
663 src_char = le16_to_cpu(source[i]);
666 goto cUCS_out; /* BB check this BB */
676 /* BB We can not handle remapping slash until
677 all the calls to build_path_from_dentry
678 are modified, as they use slash as separator BB */
692 len = cp->uni2char(src_char, &target[j],
693 NLS_MAX_CHARSET_SIZE);
702 /* make sure we do not overrun callers allocated temp buffer */
703 if (j >= (2 * NAME_MAX))
711 /* Convert 16 bit Unicode pathname to wire format from string in current code
712 page. Conversion may involve remapping up the seven characters that are
713 only legal in POSIX-like OS (if they are present in the string). Path
714 names are little endian 16 bit Unicode on the wire */
716 cifsConvertToUCS(__le16 *target, const char *source, int maxlen,
717 const struct nls_table *cp, int mapChars)
720 int len_remaining = maxlen;
725 return cifs_strtoUCS(target, source, PATH_MAX, cp);
727 for (i = 0, j = 0; i < maxlen; j++) {
728 src_char = source[i];
734 target[j] = cpu_to_le16(UNI_COLON);
737 target[j] = cpu_to_le16(UNI_ASTERIK);
740 target[j] = cpu_to_le16(UNI_QUESTION);
743 target[j] = cpu_to_le16(UNI_LESSTHAN);
746 target[j] = cpu_to_le16(UNI_GRTRTHAN);
749 target[j] = cpu_to_le16(UNI_PIPE);
751 /* BB We can not handle remapping slash until
752 all the calls to build_path_from_dentry
753 are modified, as they use slash as separator BB */
755 target[j] = cpu_to_le16(UNI_SLASH);
758 charlen = cp->char2uni(source+i,
759 len_remaining, &temp);
760 /* if no match, use question mark, which
761 at least in some cases servers as wild card */
763 target[j] = cpu_to_le16(0x003f);
766 target[j] = cpu_to_le16(temp);
767 len_remaining -= charlen;
768 /* character may take more than one byte in the
769 the source string, but will take exactly two
770 bytes in the target string */
774 i++; /* move to next char in source string */