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v3.5.6
  1/*
  2 *   fs/cifs/misc.c
  3 *
  4 *   Copyright (C) International Business Machines  Corp., 2002,2008
  5 *   Author(s): Steve French (sfrench@us.ibm.com)
  6 *
  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.
 11 *
 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.
 16 *
 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
 20 */
 21
 22#include <linux/slab.h>
 23#include <linux/ctype.h>
 24#include <linux/mempool.h>
 25#include "cifspdu.h"
 26#include "cifsglob.h"
 27#include "cifsproto.h"
 28#include "cifs_debug.h"
 29#include "smberr.h"
 30#include "nterr.h"
 31#include "cifs_unicode.h"
 
 
 
 32
 33extern mempool_t *cifs_sm_req_poolp;
 34extern mempool_t *cifs_req_poolp;
 35
 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 */
 41
 42unsigned int
 43_GetXid(void)
 44{
 45	unsigned int xid;
 46
 47	spin_lock(&GlobalMid_Lock);
 48	GlobalTotalActiveXid++;
 49
 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);
 57	return xid;
 58}
 59
 60void
 61_FreeXid(unsigned int xid)
 62{
 63	spin_lock(&GlobalMid_Lock);
 64	/* if (GlobalTotalActiveXid == 0)
 65		BUG(); */
 66	GlobalTotalActiveXid--;
 67	spin_unlock(&GlobalMid_Lock);
 68}
 69
 70struct cifs_ses *
 71sesInfoAlloc(void)
 72{
 73	struct cifs_ses *ret_buf;
 74
 75	ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL);
 76	if (ret_buf) {
 77		atomic_inc(&sesInfoAllocCount);
 78		ret_buf->status = CifsNew;
 79		++ret_buf->ses_count;
 80		INIT_LIST_HEAD(&ret_buf->smb_ses_list);
 81		INIT_LIST_HEAD(&ret_buf->tcon_list);
 82		mutex_init(&ret_buf->session_mutex);
 83	}
 84	return ret_buf;
 85}
 86
 87void
 88sesInfoFree(struct cifs_ses *buf_to_free)
 89{
 90	if (buf_to_free == NULL) {
 91		cFYI(1, "Null buffer passed to sesInfoFree");
 92		return;
 93	}
 94
 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);
102	}
103	kfree(buf_to_free->user_name);
104	kfree(buf_to_free->domainName);
 
105	kfree(buf_to_free);
106}
107
108struct cifs_tcon *
109tconInfoAlloc(void)
110{
111	struct cifs_tcon *ret_buf;
112	ret_buf = kzalloc(sizeof(struct cifs_tcon), GFP_KERNEL);
113	if (ret_buf) {
114		atomic_inc(&tconInfoAllocCount);
115		ret_buf->tidStatus = CifsNew;
116		++ret_buf->tc_count;
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);
121#endif
122	}
123	return ret_buf;
124}
125
126void
127tconInfoFree(struct cifs_tcon *buf_to_free)
128{
129	if (buf_to_free == NULL) {
130		cFYI(1, "Null buffer passed to tconInfoFree");
131		return;
132	}
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);
138	}
139	kfree(buf_to_free);
140}
141
142struct smb_hdr *
143cifs_buf_get(void)
144{
145	struct smb_hdr *ret_buf = NULL;
 
146
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);
152
153	/* clear the first few header bytes */
154	/* for most paths, more is cleared in header_assemble */
155	if (ret_buf) {
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 */
161	}
162
163	return ret_buf;
164}
165
166void
167cifs_buf_release(void *buf_to_free)
168{
169	if (buf_to_free == NULL) {
170		/* cFYI(1, "Null buffer passed to cifs_buf_release");*/
171		return;
172	}
173	mempool_free(buf_to_free, cifs_req_poolp);
174
175	atomic_dec(&bufAllocCount);
176	return;
177}
178
179struct smb_hdr *
180cifs_small_buf_get(void)
181{
182	struct smb_hdr *ret_buf = NULL;
183
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);
189	if (ret_buf) {
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 */
196
197	}
198	return ret_buf;
199}
200
201void
202cifs_small_buf_release(void *buf_to_free)
203{
204
205	if (buf_to_free == NULL) {
206		cFYI(1, "Null buffer passed to cifs_small_buf_release");
207		return;
208	}
209	mempool_free(buf_to_free, cifs_sm_req_poolp);
210
211	atomic_dec(&smBufAllocCount);
212	return;
213}
214
 
 
 
 
 
 
 
 
 
215/* NB: MID can not be set if treeCon not passed in, in that
216   case it is responsbility of caller to set the mid */
217void
218header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
219		const struct cifs_tcon *treeCon, int word_count
220		/* length of fixed section (word count) in two byte units  */)
221{
222	char *temp = (char *) buffer;
223
224	memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
225
226	buffer->smb_buf_length = cpu_to_be32(
227	    (2 * word_count) + sizeof(struct smb_hdr) -
228	    4 /*  RFC 1001 length field does not count */  +
229	    2 /* for bcc field itself */) ;
230
231	buffer->Protocol[0] = 0xFF;
232	buffer->Protocol[1] = 'S';
233	buffer->Protocol[2] = 'M';
234	buffer->Protocol[3] = 'B';
235	buffer->Command = smb_command;
236	buffer->Flags = 0x00;	/* case sensitive */
237	buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
238	buffer->Pid = cpu_to_le16((__u16)current->tgid);
239	buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
240	if (treeCon) {
241		buffer->Tid = treeCon->tid;
242		if (treeCon->ses) {
243			if (treeCon->ses->capabilities & CAP_UNICODE)
244				buffer->Flags2 |= SMBFLG2_UNICODE;
245			if (treeCon->ses->capabilities & CAP_STATUS32)
246				buffer->Flags2 |= SMBFLG2_ERR_STATUS;
247
248			/* Uid is not converted */
249			buffer->Uid = treeCon->ses->Suid;
250			buffer->Mid = get_next_mid(treeCon->ses->server);
251		}
252		if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
253			buffer->Flags2 |= SMBFLG2_DFS;
254		if (treeCon->nocase)
255			buffer->Flags  |= SMBFLG_CASELESS;
256		if ((treeCon->ses) && (treeCon->ses->server))
257			if (treeCon->ses->server->sec_mode &
258			  (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
259				buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
260	}
261
262/*  endian conversion of flags is now done just before sending */
263	buffer->WordCount = (char) word_count;
264	return;
265}
266
267static int
268check_smb_hdr(struct smb_hdr *smb, __u16 mid)
269{
270	/* does it have the right SMB "signature" ? */
271	if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) {
272		cERROR(1, "Bad protocol string signature header 0x%x",
273			*(unsigned int *)smb->Protocol);
274		return 1;
275	}
276
277	/* Make sure that message ids match */
278	if (mid != smb->Mid) {
279		cERROR(1, "Mids do not match. received=%u expected=%u",
280			smb->Mid, mid);
281		return 1;
282	}
283
284	/* if it's a response then accept */
285	if (smb->Flags & SMBFLG_RESPONSE)
286		return 0;
287
288	/* only one valid case where server sends us request */
289	if (smb->Command == SMB_COM_LOCKING_ANDX)
290		return 0;
291
292	cERROR(1, "Server sent request, not response. mid=%u", smb->Mid);
 
293	return 1;
294}
295
296int
297checkSMB(char *buf, unsigned int total_read)
298{
299	struct smb_hdr *smb = (struct smb_hdr *)buf;
300	__u16 mid = smb->Mid;
301	__u32 rfclen = be32_to_cpu(smb->smb_buf_length);
302	__u32 clc_len;  /* calculated length */
303	cFYI(0, "checkSMB Length: 0x%x, smb_buf_length: 0x%x",
304		total_read, rfclen);
305
306	/* is this frame too small to even get to a BCC? */
307	if (total_read < 2 + sizeof(struct smb_hdr)) {
308		if ((total_read >= sizeof(struct smb_hdr) - 1)
309			    && (smb->Status.CifsError != 0)) {
310			/* it's an error return */
311			smb->WordCount = 0;
312			/* some error cases do not return wct and bcc */
313			return 0;
314		} else if ((total_read == sizeof(struct smb_hdr) + 1) &&
315				(smb->WordCount == 0)) {
316			char *tmp = (char *)smb;
317			/* Need to work around a bug in two servers here */
318			/* First, check if the part of bcc they sent was zero */
319			if (tmp[sizeof(struct smb_hdr)] == 0) {
320				/* some servers return only half of bcc
321				 * on simple responses (wct, bcc both zero)
322				 * in particular have seen this on
323				 * ulogoffX and FindClose. This leaves
324				 * one byte of bcc potentially unitialized
325				 */
326				/* zero rest of bcc */
327				tmp[sizeof(struct smb_hdr)+1] = 0;
328				return 0;
329			}
330			cERROR(1, "rcvd invalid byte count (bcc)");
331		} else {
332			cERROR(1, "Length less than smb header size");
333		}
334		return -EIO;
335	}
336
337	/* otherwise, there is enough to get to the BCC */
338	if (check_smb_hdr(smb, mid))
339		return -EIO;
340	clc_len = smbCalcSize(smb);
341
342	if (4 + rfclen != total_read) {
343		cERROR(1, "Length read does not match RFC1001 length %d",
344				rfclen);
345		return -EIO;
346	}
347
348	if (4 + rfclen != clc_len) {
 
349		/* check if bcc wrapped around for large read responses */
350		if ((rfclen > 64 * 1024) && (rfclen > clc_len)) {
351			/* check if lengths match mod 64K */
352			if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF))
353				return 0; /* bcc wrapped */
354		}
355		cFYI(1, "Calculated size %u vs length %u mismatch for mid=%u",
356				clc_len, 4 + rfclen, smb->Mid);
357
358		if (4 + rfclen < clc_len) {
359			cERROR(1, "RFC1001 size %u smaller than SMB for mid=%u",
360					rfclen, smb->Mid);
361			return -EIO;
362		} else if (rfclen > clc_len + 512) {
363			/*
364			 * Some servers (Windows XP in particular) send more
365			 * data than the lengths in the SMB packet would
366			 * indicate on certain calls (byte range locks and
367			 * trans2 find first calls in particular). While the
368			 * client can handle such a frame by ignoring the
369			 * trailing data, we choose limit the amount of extra
370			 * data to 512 bytes.
371			 */
372			cERROR(1, "RFC1001 size %u more than 512 bytes larger "
373				  "than SMB for mid=%u", rfclen, smb->Mid);
374			return -EIO;
375		}
376	}
377	return 0;
378}
379
380bool
381is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv)
382{
383	struct smb_hdr *buf = (struct smb_hdr *)buffer;
384	struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;
385	struct list_head *tmp, *tmp1, *tmp2;
386	struct cifs_ses *ses;
387	struct cifs_tcon *tcon;
388	struct cifsInodeInfo *pCifsInode;
389	struct cifsFileInfo *netfile;
390
391	cFYI(1, "Checking for oplock break or dnotify response");
392	if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
393	   (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {
394		struct smb_com_transaction_change_notify_rsp *pSMBr =
395			(struct smb_com_transaction_change_notify_rsp *)buf;
396		struct file_notify_information *pnotify;
397		__u32 data_offset = 0;
398		if (get_bcc(buf) > sizeof(struct file_notify_information)) {
399			data_offset = le32_to_cpu(pSMBr->DataOffset);
400
401			pnotify = (struct file_notify_information *)
402				((char *)&pSMBr->hdr.Protocol + data_offset);
403			cFYI(1, "dnotify on %s Action: 0x%x",
404				 pnotify->FileName, pnotify->Action);
405			/*   cifs_dump_mem("Rcvd notify Data: ",buf,
406				sizeof(struct smb_hdr)+60); */
407			return true;
408		}
409		if (pSMBr->hdr.Status.CifsError) {
410			cFYI(1, "notify err 0x%d",
411				pSMBr->hdr.Status.CifsError);
412			return true;
413		}
414		return false;
415	}
416	if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
417		return false;
418	if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {
419		/* no sense logging error on invalid handle on oplock
420		   break - harmless race between close request and oplock
421		   break response is expected from time to time writing out
422		   large dirty files cached on the client */
423		if ((NT_STATUS_INVALID_HANDLE) ==
424		   le32_to_cpu(pSMB->hdr.Status.CifsError)) {
425			cFYI(1, "invalid handle on oplock break");
426			return true;
427		} else if (ERRbadfid ==
428		   le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
429			return true;
430		} else {
431			return false; /* on valid oplock brk we get "request" */
432		}
433	}
434	if (pSMB->hdr.WordCount != 8)
435		return false;
436
437	cFYI(1, "oplock type 0x%d level 0x%d",
438		 pSMB->LockType, pSMB->OplockLevel);
439	if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
440		return false;
441
442	/* look up tcon based on tid & uid */
443	spin_lock(&cifs_tcp_ses_lock);
444	list_for_each(tmp, &srv->smb_ses_list) {
445		ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
446		list_for_each(tmp1, &ses->tcon_list) {
447			tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
448			if (tcon->tid != buf->Tid)
449				continue;
450
451			cifs_stats_inc(&tcon->num_oplock_brks);
452			spin_lock(&cifs_file_list_lock);
453			list_for_each(tmp2, &tcon->openFileList) {
454				netfile = list_entry(tmp2, struct cifsFileInfo,
455						     tlist);
456				if (pSMB->Fid != netfile->netfid)
457					continue;
458
459				cFYI(1, "file id match, oplock break");
460				pCifsInode = CIFS_I(netfile->dentry->d_inode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
461
462				cifs_set_oplock_level(pCifsInode,
463					pSMB->OplockLevel ? OPLOCK_READ : 0);
464				queue_work(cifsiod_wq,
465					   &netfile->oplock_break);
466				netfile->oplock_break_cancelled = false;
467
468				spin_unlock(&cifs_file_list_lock);
469				spin_unlock(&cifs_tcp_ses_lock);
470				return true;
471			}
472			spin_unlock(&cifs_file_list_lock);
473			spin_unlock(&cifs_tcp_ses_lock);
474			cFYI(1, "No matching file for oplock break");
475			return true;
476		}
477	}
478	spin_unlock(&cifs_tcp_ses_lock);
479	cFYI(1, "Can not process oplock break for non-existent connection");
480	return true;
481}
482
483void
484dump_smb(void *buf, int smb_buf_length)
485{
486	int i, j;
487	char debug_line[17];
488	unsigned char *buffer = buf;
489
490	if (traceSMB == 0)
491		return;
492
493	for (i = 0, j = 0; i < smb_buf_length; i++, j++) {
494		if (i % 8 == 0) {
495			/* have reached the beginning of line */
496			printk(KERN_DEBUG "| ");
497			j = 0;
498		}
499		printk("%0#4x ", buffer[i]);
500		debug_line[2 * j] = ' ';
501		if (isprint(buffer[i]))
502			debug_line[1 + (2 * j)] = buffer[i];
503		else
504			debug_line[1 + (2 * j)] = '_';
505
506		if (i % 8 == 7) {
507			/* reached end of line, time to print ascii */
508			debug_line[16] = 0;
509			printk(" | %s\n", debug_line);
510		}
511	}
512	for (; j < 8; j++) {
513		printk("     ");
514		debug_line[2 * j] = ' ';
515		debug_line[1 + (2 * j)] = ' ';
516	}
517	printk(" | %s\n", debug_line);
518	return;
519}
520
521void
522cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)
523{
524	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
525		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
526		cERROR(1, "Autodisabling the use of server inode numbers on "
527			   "%s. This server doesn't seem to support them "
528			   "properly. Hardlinks will not be recognized on this "
529			   "mount. Consider mounting with the \"noserverino\" "
530			   "option to silence this message.",
531			   cifs_sb_master_tcon(cifs_sb)->treeName);
532	}
533}
534
535void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
536{
537	oplock &= 0xF;
538
539	if (oplock == OPLOCK_EXCLUSIVE) {
540		cinode->clientCanCacheAll = true;
541		cinode->clientCanCacheRead = true;
542		cFYI(1, "Exclusive Oplock granted on inode %p",
543		     &cinode->vfs_inode);
544	} else if (oplock == OPLOCK_READ) {
545		cinode->clientCanCacheAll = false;
546		cinode->clientCanCacheRead = true;
547		cFYI(1, "Level II Oplock granted on inode %p",
548		    &cinode->vfs_inode);
549	} else {
550		cinode->clientCanCacheAll = false;
551		cinode->clientCanCacheRead = false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
552	}
 
 
 
 
 
 
 
553}
554
555bool
556backup_cred(struct cifs_sb_info *cifs_sb)
557{
558	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) {
559		if (cifs_sb->mnt_backupuid == current_fsuid())
560			return true;
561	}
562	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) {
563		if (in_group_p(cifs_sb->mnt_backupgid))
564			return true;
565	}
566
567	return false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
568}
v4.10.11
  1/*
  2 *   fs/cifs/misc.c
  3 *
  4 *   Copyright (C) International Business Machines  Corp., 2002,2008
  5 *   Author(s): Steve French (sfrench@us.ibm.com)
  6 *
  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.
 11 *
 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.
 16 *
 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
 20 */
 21
 22#include <linux/slab.h>
 23#include <linux/ctype.h>
 24#include <linux/mempool.h>
 25#include "cifspdu.h"
 26#include "cifsglob.h"
 27#include "cifsproto.h"
 28#include "cifs_debug.h"
 29#include "smberr.h"
 30#include "nterr.h"
 31#include "cifs_unicode.h"
 32#ifdef CONFIG_CIFS_SMB2
 33#include "smb2pdu.h"
 34#endif
 35
 36extern mempool_t *cifs_sm_req_poolp;
 37extern mempool_t *cifs_req_poolp;
 38
 39/* The xid serves as a useful identifier for each incoming vfs request,
 40   in a similar way to the mid which is useful to track each sent smb,
 41   and CurrentXid can also provide a running counter (although it
 42   will eventually wrap past zero) of the total vfs operations handled
 43   since the cifs fs was mounted */
 44
 45unsigned int
 46_get_xid(void)
 47{
 48	unsigned int xid;
 49
 50	spin_lock(&GlobalMid_Lock);
 51	GlobalTotalActiveXid++;
 52
 53	/* keep high water mark for number of simultaneous ops in filesystem */
 54	if (GlobalTotalActiveXid > GlobalMaxActiveXid)
 55		GlobalMaxActiveXid = GlobalTotalActiveXid;
 56	if (GlobalTotalActiveXid > 65000)
 57		cifs_dbg(FYI, "warning: more than 65000 requests active\n");
 58	xid = GlobalCurrentXid++;
 59	spin_unlock(&GlobalMid_Lock);
 60	return xid;
 61}
 62
 63void
 64_free_xid(unsigned int xid)
 65{
 66	spin_lock(&GlobalMid_Lock);
 67	/* if (GlobalTotalActiveXid == 0)
 68		BUG(); */
 69	GlobalTotalActiveXid--;
 70	spin_unlock(&GlobalMid_Lock);
 71}
 72
 73struct cifs_ses *
 74sesInfoAlloc(void)
 75{
 76	struct cifs_ses *ret_buf;
 77
 78	ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL);
 79	if (ret_buf) {
 80		atomic_inc(&sesInfoAllocCount);
 81		ret_buf->status = CifsNew;
 82		++ret_buf->ses_count;
 83		INIT_LIST_HEAD(&ret_buf->smb_ses_list);
 84		INIT_LIST_HEAD(&ret_buf->tcon_list);
 85		mutex_init(&ret_buf->session_mutex);
 86	}
 87	return ret_buf;
 88}
 89
 90void
 91sesInfoFree(struct cifs_ses *buf_to_free)
 92{
 93	if (buf_to_free == NULL) {
 94		cifs_dbg(FYI, "Null buffer passed to sesInfoFree\n");
 95		return;
 96	}
 97
 98	atomic_dec(&sesInfoAllocCount);
 99	kfree(buf_to_free->serverOS);
100	kfree(buf_to_free->serverDomain);
101	kfree(buf_to_free->serverNOS);
102	if (buf_to_free->password) {
103		memset(buf_to_free->password, 0, strlen(buf_to_free->password));
104		kfree(buf_to_free->password);
105	}
106	kfree(buf_to_free->user_name);
107	kfree(buf_to_free->domainName);
108	kfree(buf_to_free->auth_key.response);
109	kfree(buf_to_free);
110}
111
112struct cifs_tcon *
113tconInfoAlloc(void)
114{
115	struct cifs_tcon *ret_buf;
116	ret_buf = kzalloc(sizeof(struct cifs_tcon), GFP_KERNEL);
117	if (ret_buf) {
118		atomic_inc(&tconInfoAllocCount);
119		ret_buf->tidStatus = CifsNew;
120		++ret_buf->tc_count;
121		INIT_LIST_HEAD(&ret_buf->openFileList);
122		INIT_LIST_HEAD(&ret_buf->tcon_list);
123		spin_lock_init(&ret_buf->open_file_lock);
124#ifdef CONFIG_CIFS_STATS
125		spin_lock_init(&ret_buf->stat_lock);
126#endif
127	}
128	return ret_buf;
129}
130
131void
132tconInfoFree(struct cifs_tcon *buf_to_free)
133{
134	if (buf_to_free == NULL) {
135		cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n");
136		return;
137	}
138	atomic_dec(&tconInfoAllocCount);
139	kfree(buf_to_free->nativeFileSystem);
140	if (buf_to_free->password) {
141		memset(buf_to_free->password, 0, strlen(buf_to_free->password));
142		kfree(buf_to_free->password);
143	}
144	kfree(buf_to_free);
145}
146
147struct smb_hdr *
148cifs_buf_get(void)
149{
150	struct smb_hdr *ret_buf = NULL;
151	size_t buf_size = sizeof(struct smb_hdr);
152
153#ifdef CONFIG_CIFS_SMB2
154	/*
155	 * SMB2 header is bigger than CIFS one - no problems to clean some
156	 * more bytes for CIFS.
157	 */
158	buf_size = sizeof(struct smb2_hdr);
159#endif
160	/*
161	 * We could use negotiated size instead of max_msgsize -
162	 * but it may be more efficient to always alloc same size
163	 * albeit slightly larger than necessary and maxbuffersize
164	 * defaults to this and can not be bigger.
165	 */
166	ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS);
167
168	/* clear the first few header bytes */
169	/* for most paths, more is cleared in header_assemble */
170	if (ret_buf) {
171		memset(ret_buf, 0, buf_size + 3);
172		atomic_inc(&bufAllocCount);
173#ifdef CONFIG_CIFS_STATS2
174		atomic_inc(&totBufAllocCount);
175#endif /* CONFIG_CIFS_STATS2 */
176	}
177
178	return ret_buf;
179}
180
181void
182cifs_buf_release(void *buf_to_free)
183{
184	if (buf_to_free == NULL) {
185		/* cifs_dbg(FYI, "Null buffer passed to cifs_buf_release\n");*/
186		return;
187	}
188	mempool_free(buf_to_free, cifs_req_poolp);
189
190	atomic_dec(&bufAllocCount);
191	return;
192}
193
194struct smb_hdr *
195cifs_small_buf_get(void)
196{
197	struct smb_hdr *ret_buf = NULL;
198
199/* We could use negotiated size instead of max_msgsize -
200   but it may be more efficient to always alloc same size
201   albeit slightly larger than necessary and maxbuffersize
202   defaults to this and can not be bigger */
203	ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS);
204	if (ret_buf) {
205	/* No need to clear memory here, cleared in header assemble */
206	/*	memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
207		atomic_inc(&smBufAllocCount);
208#ifdef CONFIG_CIFS_STATS2
209		atomic_inc(&totSmBufAllocCount);
210#endif /* CONFIG_CIFS_STATS2 */
211
212	}
213	return ret_buf;
214}
215
216void
217cifs_small_buf_release(void *buf_to_free)
218{
219
220	if (buf_to_free == NULL) {
221		cifs_dbg(FYI, "Null buffer passed to cifs_small_buf_release\n");
222		return;
223	}
224	mempool_free(buf_to_free, cifs_sm_req_poolp);
225
226	atomic_dec(&smBufAllocCount);
227	return;
228}
229
230void
231free_rsp_buf(int resp_buftype, void *rsp)
232{
233	if (resp_buftype == CIFS_SMALL_BUFFER)
234		cifs_small_buf_release(rsp);
235	else if (resp_buftype == CIFS_LARGE_BUFFER)
236		cifs_buf_release(rsp);
237}
238
239/* NB: MID can not be set if treeCon not passed in, in that
240   case it is responsbility of caller to set the mid */
241void
242header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
243		const struct cifs_tcon *treeCon, int word_count
244		/* length of fixed section (word count) in two byte units  */)
245{
246	char *temp = (char *) buffer;
247
248	memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
249
250	buffer->smb_buf_length = cpu_to_be32(
251	    (2 * word_count) + sizeof(struct smb_hdr) -
252	    4 /*  RFC 1001 length field does not count */  +
253	    2 /* for bcc field itself */) ;
254
255	buffer->Protocol[0] = 0xFF;
256	buffer->Protocol[1] = 'S';
257	buffer->Protocol[2] = 'M';
258	buffer->Protocol[3] = 'B';
259	buffer->Command = smb_command;
260	buffer->Flags = 0x00;	/* case sensitive */
261	buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
262	buffer->Pid = cpu_to_le16((__u16)current->tgid);
263	buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
264	if (treeCon) {
265		buffer->Tid = treeCon->tid;
266		if (treeCon->ses) {
267			if (treeCon->ses->capabilities & CAP_UNICODE)
268				buffer->Flags2 |= SMBFLG2_UNICODE;
269			if (treeCon->ses->capabilities & CAP_STATUS32)
270				buffer->Flags2 |= SMBFLG2_ERR_STATUS;
271
272			/* Uid is not converted */
273			buffer->Uid = treeCon->ses->Suid;
274			buffer->Mid = get_next_mid(treeCon->ses->server);
275		}
276		if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
277			buffer->Flags2 |= SMBFLG2_DFS;
278		if (treeCon->nocase)
279			buffer->Flags  |= SMBFLG_CASELESS;
280		if ((treeCon->ses) && (treeCon->ses->server))
281			if (treeCon->ses->server->sign)
 
282				buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
283	}
284
285/*  endian conversion of flags is now done just before sending */
286	buffer->WordCount = (char) word_count;
287	return;
288}
289
290static int
291check_smb_hdr(struct smb_hdr *smb)
292{
293	/* does it have the right SMB "signature" ? */
294	if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) {
295		cifs_dbg(VFS, "Bad protocol string signature header 0x%x\n",
296			 *(unsigned int *)smb->Protocol);
 
 
 
 
 
 
 
297		return 1;
298	}
299
300	/* if it's a response then accept */
301	if (smb->Flags & SMBFLG_RESPONSE)
302		return 0;
303
304	/* only one valid case where server sends us request */
305	if (smb->Command == SMB_COM_LOCKING_ANDX)
306		return 0;
307
308	cifs_dbg(VFS, "Server sent request, not response. mid=%u\n",
309		 get_mid(smb));
310	return 1;
311}
312
313int
314checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server)
315{
316	struct smb_hdr *smb = (struct smb_hdr *)buf;
 
317	__u32 rfclen = be32_to_cpu(smb->smb_buf_length);
318	__u32 clc_len;  /* calculated length */
319	cifs_dbg(FYI, "checkSMB Length: 0x%x, smb_buf_length: 0x%x\n",
320		 total_read, rfclen);
321
322	/* is this frame too small to even get to a BCC? */
323	if (total_read < 2 + sizeof(struct smb_hdr)) {
324		if ((total_read >= sizeof(struct smb_hdr) - 1)
325			    && (smb->Status.CifsError != 0)) {
326			/* it's an error return */
327			smb->WordCount = 0;
328			/* some error cases do not return wct and bcc */
329			return 0;
330		} else if ((total_read == sizeof(struct smb_hdr) + 1) &&
331				(smb->WordCount == 0)) {
332			char *tmp = (char *)smb;
333			/* Need to work around a bug in two servers here */
334			/* First, check if the part of bcc they sent was zero */
335			if (tmp[sizeof(struct smb_hdr)] == 0) {
336				/* some servers return only half of bcc
337				 * on simple responses (wct, bcc both zero)
338				 * in particular have seen this on
339				 * ulogoffX and FindClose. This leaves
340				 * one byte of bcc potentially unitialized
341				 */
342				/* zero rest of bcc */
343				tmp[sizeof(struct smb_hdr)+1] = 0;
344				return 0;
345			}
346			cifs_dbg(VFS, "rcvd invalid byte count (bcc)\n");
347		} else {
348			cifs_dbg(VFS, "Length less than smb header size\n");
349		}
350		return -EIO;
351	}
352
353	/* otherwise, there is enough to get to the BCC */
354	if (check_smb_hdr(smb))
355		return -EIO;
356	clc_len = smbCalcSize(smb);
357
358	if (4 + rfclen != total_read) {
359		cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n",
360			 rfclen);
361		return -EIO;
362	}
363
364	if (4 + rfclen != clc_len) {
365		__u16 mid = get_mid(smb);
366		/* check if bcc wrapped around for large read responses */
367		if ((rfclen > 64 * 1024) && (rfclen > clc_len)) {
368			/* check if lengths match mod 64K */
369			if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF))
370				return 0; /* bcc wrapped */
371		}
372		cifs_dbg(FYI, "Calculated size %u vs length %u mismatch for mid=%u\n",
373			 clc_len, 4 + rfclen, mid);
374
375		if (4 + rfclen < clc_len) {
376			cifs_dbg(VFS, "RFC1001 size %u smaller than SMB for mid=%u\n",
377				 rfclen, mid);
378			return -EIO;
379		} else if (rfclen > clc_len + 512) {
380			/*
381			 * Some servers (Windows XP in particular) send more
382			 * data than the lengths in the SMB packet would
383			 * indicate on certain calls (byte range locks and
384			 * trans2 find first calls in particular). While the
385			 * client can handle such a frame by ignoring the
386			 * trailing data, we choose limit the amount of extra
387			 * data to 512 bytes.
388			 */
389			cifs_dbg(VFS, "RFC1001 size %u more than 512 bytes larger than SMB for mid=%u\n",
390				 rfclen, mid);
391			return -EIO;
392		}
393	}
394	return 0;
395}
396
397bool
398is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv)
399{
400	struct smb_hdr *buf = (struct smb_hdr *)buffer;
401	struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;
402	struct list_head *tmp, *tmp1, *tmp2;
403	struct cifs_ses *ses;
404	struct cifs_tcon *tcon;
405	struct cifsInodeInfo *pCifsInode;
406	struct cifsFileInfo *netfile;
407
408	cifs_dbg(FYI, "Checking for oplock break or dnotify response\n");
409	if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
410	   (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {
411		struct smb_com_transaction_change_notify_rsp *pSMBr =
412			(struct smb_com_transaction_change_notify_rsp *)buf;
413		struct file_notify_information *pnotify;
414		__u32 data_offset = 0;
415		if (get_bcc(buf) > sizeof(struct file_notify_information)) {
416			data_offset = le32_to_cpu(pSMBr->DataOffset);
417
418			pnotify = (struct file_notify_information *)
419				((char *)&pSMBr->hdr.Protocol + data_offset);
420			cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n",
421				 pnotify->FileName, pnotify->Action);
422			/*   cifs_dump_mem("Rcvd notify Data: ",buf,
423				sizeof(struct smb_hdr)+60); */
424			return true;
425		}
426		if (pSMBr->hdr.Status.CifsError) {
427			cifs_dbg(FYI, "notify err 0x%x\n",
428				 pSMBr->hdr.Status.CifsError);
429			return true;
430		}
431		return false;
432	}
433	if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
434		return false;
435	if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {
436		/* no sense logging error on invalid handle on oplock
437		   break - harmless race between close request and oplock
438		   break response is expected from time to time writing out
439		   large dirty files cached on the client */
440		if ((NT_STATUS_INVALID_HANDLE) ==
441		   le32_to_cpu(pSMB->hdr.Status.CifsError)) {
442			cifs_dbg(FYI, "invalid handle on oplock break\n");
443			return true;
444		} else if (ERRbadfid ==
445		   le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
446			return true;
447		} else {
448			return false; /* on valid oplock brk we get "request" */
449		}
450	}
451	if (pSMB->hdr.WordCount != 8)
452		return false;
453
454	cifs_dbg(FYI, "oplock type 0x%x level 0x%x\n",
455		 pSMB->LockType, pSMB->OplockLevel);
456	if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
457		return false;
458
459	/* look up tcon based on tid & uid */
460	spin_lock(&cifs_tcp_ses_lock);
461	list_for_each(tmp, &srv->smb_ses_list) {
462		ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
463		list_for_each(tmp1, &ses->tcon_list) {
464			tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
465			if (tcon->tid != buf->Tid)
466				continue;
467
468			cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
469			spin_lock(&tcon->open_file_lock);
470			list_for_each(tmp2, &tcon->openFileList) {
471				netfile = list_entry(tmp2, struct cifsFileInfo,
472						     tlist);
473				if (pSMB->Fid != netfile->fid.netfid)
474					continue;
475
476				cifs_dbg(FYI, "file id match, oplock break\n");
477				pCifsInode = CIFS_I(d_inode(netfile->dentry));
478
479				set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
480					&pCifsInode->flags);
481
482				/*
483				 * Set flag if the server downgrades the oplock
484				 * to L2 else clear.
485				 */
486				if (pSMB->OplockLevel)
487					set_bit(
488					   CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
489					   &pCifsInode->flags);
490				else
491					clear_bit(
492					   CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
493					   &pCifsInode->flags);
494
 
 
495				queue_work(cifsiod_wq,
496					   &netfile->oplock_break);
497				netfile->oplock_break_cancelled = false;
498
499				spin_unlock(&tcon->open_file_lock);
500				spin_unlock(&cifs_tcp_ses_lock);
501				return true;
502			}
503			spin_unlock(&tcon->open_file_lock);
504			spin_unlock(&cifs_tcp_ses_lock);
505			cifs_dbg(FYI, "No matching file for oplock break\n");
506			return true;
507		}
508	}
509	spin_unlock(&cifs_tcp_ses_lock);
510	cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
511	return true;
512}
513
514void
515dump_smb(void *buf, int smb_buf_length)
516{
 
 
 
 
517	if (traceSMB == 0)
518		return;
519
520	print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE, 8, 2, buf,
521		       smb_buf_length, true);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
522}
523
524void
525cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)
526{
527	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
528		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
529		cifs_dbg(VFS, "Autodisabling the use of server inode numbers on %s. This server doesn't seem to support them properly. Hardlinks will not be recognized on this mount. Consider mounting with the \"noserverino\" option to silence this message.\n",
530			 cifs_sb_master_tcon(cifs_sb)->treeName);
 
 
 
 
531	}
532}
533
534void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
535{
536	oplock &= 0xF;
537
538	if (oplock == OPLOCK_EXCLUSIVE) {
539		cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG;
540		cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n",
541			 &cinode->vfs_inode);
 
542	} else if (oplock == OPLOCK_READ) {
543		cinode->oplock = CIFS_CACHE_READ_FLG;
544		cifs_dbg(FYI, "Level II Oplock granted on inode %p\n",
545			 &cinode->vfs_inode);
546	} else
547		cinode->oplock = 0;
548}
549
550/*
551 * We wait for oplock breaks to be processed before we attempt to perform
552 * writes.
553 */
554int cifs_get_writer(struct cifsInodeInfo *cinode)
555{
556	int rc;
557
558start:
559	rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK,
560			 TASK_KILLABLE);
561	if (rc)
562		return rc;
563
564	spin_lock(&cinode->writers_lock);
565	if (!cinode->writers)
566		set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
567	cinode->writers++;
568	/* Check to see if we have started servicing an oplock break */
569	if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) {
570		cinode->writers--;
571		if (cinode->writers == 0) {
572			clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
573			wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
574		}
575		spin_unlock(&cinode->writers_lock);
576		goto start;
577	}
578	spin_unlock(&cinode->writers_lock);
579	return 0;
580}
581
582void cifs_put_writer(struct cifsInodeInfo *cinode)
583{
584	spin_lock(&cinode->writers_lock);
585	cinode->writers--;
586	if (cinode->writers == 0) {
587		clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
588		wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
589	}
590	spin_unlock(&cinode->writers_lock);
591}
592
593void cifs_done_oplock_break(struct cifsInodeInfo *cinode)
594{
595	clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
596	wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK);
597}
598
599bool
600backup_cred(struct cifs_sb_info *cifs_sb)
601{
602	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) {
603		if (uid_eq(cifs_sb->mnt_backupuid, current_fsuid()))
604			return true;
605	}
606	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) {
607		if (in_group_p(cifs_sb->mnt_backupgid))
608			return true;
609	}
610
611	return false;
612}
613
614void
615cifs_del_pending_open(struct cifs_pending_open *open)
616{
617	spin_lock(&tlink_tcon(open->tlink)->open_file_lock);
618	list_del(&open->olist);
619	spin_unlock(&tlink_tcon(open->tlink)->open_file_lock);
620}
621
622void
623cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink,
624			     struct cifs_pending_open *open)
625{
626#ifdef CONFIG_CIFS_SMB2
627	memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE);
628#endif
629	open->oplock = CIFS_OPLOCK_NO_CHANGE;
630	open->tlink = tlink;
631	fid->pending_open = open;
632	list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens);
633}
634
635void
636cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink,
637		      struct cifs_pending_open *open)
638{
639	spin_lock(&tlink_tcon(tlink)->open_file_lock);
640	cifs_add_pending_open_locked(fid, tlink, open);
641	spin_unlock(&tlink_tcon(open->tlink)->open_file_lock);
642}