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  1/*
  2 *   fs/cifs/smb2misc.c
  3 *
  4 *   Copyright (C) International Business Machines  Corp., 2002,2011
  5 *                 Etersoft, 2012
  6 *   Author(s): Steve French (sfrench@us.ibm.com)
  7 *              Pavel Shilovsky (pshilovsky@samba.org) 2012
  8 *
  9 *   This library is free software; you can redistribute it and/or modify
 10 *   it under the terms of the GNU Lesser General Public License as published
 11 *   by the Free Software Foundation; either version 2.1 of the License, or
 12 *   (at your option) any later version.
 13 *
 14 *   This library is distributed in the hope that it will be useful,
 15 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 17 *   the GNU Lesser General Public License for more details.
 18 *
 19 *   You should have received a copy of the GNU Lesser General Public License
 20 *   along with this library; if not, write to the Free Software
 21 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 22 */
 23#include <linux/ctype.h>
 24#include "smb2pdu.h"
 25#include "cifsglob.h"
 26#include "cifsproto.h"
 27#include "smb2proto.h"
 28#include "cifs_debug.h"
 29#include "cifs_unicode.h"
 30#include "smb2status.h"
 31#include "smb2glob.h"
 32#include "nterr.h"
 33
 34static int
 35check_smb2_hdr(struct smb2_sync_hdr *shdr, __u64 mid)
 36{
 37	__u64 wire_mid = le64_to_cpu(shdr->MessageId);
 38
 39	/*
 40	 * Make sure that this really is an SMB, that it is a response,
 41	 * and that the message ids match.
 42	 */
 43	if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
 44	    (mid == wire_mid)) {
 45		if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
 46			return 0;
 47		else {
 48			/* only one valid case where server sends us request */
 49			if (shdr->Command == SMB2_OPLOCK_BREAK)
 50				return 0;
 51			else
 52				cifs_dbg(VFS, "Received Request not response\n");
 53		}
 54	} else { /* bad signature or mid */
 55		if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
 56			cifs_dbg(VFS, "Bad protocol string signature header %x\n",
 57				 le32_to_cpu(shdr->ProtocolId));
 58		if (mid != wire_mid)
 59			cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
 60				 mid, wire_mid);
 61	}
 62	cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
 63	return 1;
 64}
 65
 66/*
 67 *  The following table defines the expected "StructureSize" of SMB2 responses
 68 *  in order by SMB2 command.  This is similar to "wct" in SMB/CIFS responses.
 69 *
 70 *  Note that commands are defined in smb2pdu.h in le16 but the array below is
 71 *  indexed by command in host byte order
 72 */
 73static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
 74	/* SMB2_NEGOTIATE */ cpu_to_le16(65),
 75	/* SMB2_SESSION_SETUP */ cpu_to_le16(9),
 76	/* SMB2_LOGOFF */ cpu_to_le16(4),
 77	/* SMB2_TREE_CONNECT */ cpu_to_le16(16),
 78	/* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
 79	/* SMB2_CREATE */ cpu_to_le16(89),
 80	/* SMB2_CLOSE */ cpu_to_le16(60),
 81	/* SMB2_FLUSH */ cpu_to_le16(4),
 82	/* SMB2_READ */ cpu_to_le16(17),
 83	/* SMB2_WRITE */ cpu_to_le16(17),
 84	/* SMB2_LOCK */ cpu_to_le16(4),
 85	/* SMB2_IOCTL */ cpu_to_le16(49),
 86	/* BB CHECK this ... not listed in documentation */
 87	/* SMB2_CANCEL */ cpu_to_le16(0),
 88	/* SMB2_ECHO */ cpu_to_le16(4),
 89	/* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
 90	/* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
 91	/* SMB2_QUERY_INFO */ cpu_to_le16(9),
 92	/* SMB2_SET_INFO */ cpu_to_le16(2),
 93	/* BB FIXME can also be 44 for lease break */
 94	/* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
 95};
 96
 97static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len,
 98			      __u32 non_ctxlen)
 99{
100	__u16 neg_count;
101	__u32 nc_offset, size_of_pad_before_neg_ctxts;
102	struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
103
104	/* Negotiate contexts are only valid for latest dialect SMB3.11 */
105	neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
106	if ((neg_count == 0) ||
107	   (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
108		return 0;
109
110	/* Make sure that negotiate contexts start after gss security blob */
111	nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
112	if (nc_offset < non_ctxlen) {
113		pr_warn_once("Invalid negotiate context offset\n");
114		return 0;
115	}
116	size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
117
118	/* Verify that at least minimal negotiate contexts fit within frame */
119	if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
120		pr_warn_once("negotiate context goes beyond end\n");
121		return 0;
122	}
123
124	cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
125		len - nc_offset, size_of_pad_before_neg_ctxts);
126
127	/* length of negcontexts including pad from end of sec blob to them */
128	return (len - nc_offset) + size_of_pad_before_neg_ctxts;
129}
130
131int
132smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
133{
134	struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
135	struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)shdr;
136	__u64 mid;
137	__u32 clc_len;  /* calculated length */
138	int command;
139	int pdu_size = sizeof(struct smb2_sync_pdu);
140	int hdr_size = sizeof(struct smb2_sync_hdr);
141
142	/*
143	 * Add function to do table lookup of StructureSize by command
144	 * ie Validate the wct via smb2_struct_sizes table above
145	 */
146	if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
147		struct smb2_transform_hdr *thdr =
148			(struct smb2_transform_hdr *)buf;
149		struct cifs_ses *ses = NULL;
150		struct list_head *tmp;
151
152		/* decrypt frame now that it is completely read in */
153		spin_lock(&cifs_tcp_ses_lock);
154		list_for_each(tmp, &srvr->smb_ses_list) {
155			ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
156			if (ses->Suid == thdr->SessionId)
157				break;
158
159			ses = NULL;
160		}
161		spin_unlock(&cifs_tcp_ses_lock);
162		if (ses == NULL) {
163			cifs_dbg(VFS, "no decryption - session id not found\n");
164			return 1;
165		}
166	}
167
168	mid = le64_to_cpu(shdr->MessageId);
169	if (len < pdu_size) {
170		if ((len >= hdr_size)
171		    && (shdr->Status != 0)) {
172			pdu->StructureSize2 = 0;
173			/*
174			 * As with SMB/CIFS, on some error cases servers may
175			 * not return wct properly
176			 */
177			return 0;
178		} else {
179			cifs_dbg(VFS, "Length less than SMB header size\n");
180		}
181		return 1;
182	}
183	if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
184		cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
185			 mid);
186		return 1;
187	}
188
189	if (check_smb2_hdr(shdr, mid))
190		return 1;
191
192	if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
193		cifs_dbg(VFS, "Invalid structure size %u\n",
194			 le16_to_cpu(shdr->StructureSize));
195		return 1;
196	}
197
198	command = le16_to_cpu(shdr->Command);
199	if (command >= NUMBER_OF_SMB2_COMMANDS) {
200		cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
201		return 1;
202	}
203
204	if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
205		if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
206		    pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
207			/* error packets have 9 byte structure size */
208			cifs_dbg(VFS, "Invalid response size %u for command %d\n",
209				 le16_to_cpu(pdu->StructureSize2), command);
210			return 1;
211		} else if (command == SMB2_OPLOCK_BREAK_HE
212			   && (shdr->Status == 0)
213			   && (le16_to_cpu(pdu->StructureSize2) != 44)
214			   && (le16_to_cpu(pdu->StructureSize2) != 36)) {
215			/* special case for SMB2.1 lease break message */
216			cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
217				 le16_to_cpu(pdu->StructureSize2));
218			return 1;
219		}
220	}
221
222	clc_len = smb2_calc_size(buf, srvr);
223
224	if (shdr->Command == SMB2_NEGOTIATE)
225		clc_len += get_neg_ctxt_len(shdr, len, clc_len);
226
227	if (len != clc_len) {
228		cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
229			 clc_len, len, mid);
230		/* create failed on symlink */
231		if (command == SMB2_CREATE_HE &&
232		    shdr->Status == STATUS_STOPPED_ON_SYMLINK)
233			return 0;
234		/* Windows 7 server returns 24 bytes more */
235		if (clc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
236			return 0;
237		/* server can return one byte more due to implied bcc[0] */
238		if (clc_len == len + 1)
239			return 0;
240
241		/*
242		 * Some windows servers (win2016) will pad also the final
243		 * PDU in a compound to 8 bytes.
244		 */
245		if (((clc_len + 7) & ~7) == len)
246			return 0;
247
248		/*
249		 * MacOS server pads after SMB2.1 write response with 3 bytes
250		 * of junk. Other servers match RFC1001 len to actual
251		 * SMB2/SMB3 frame length (header + smb2 response specific data)
252		 * Some windows servers also pad up to 8 bytes when compounding.
253		 */
254		if (clc_len < len)
255			return 0;
256
257		pr_warn_once(
258			"srv rsp too short, len %d not %d. cmd:%d mid:%llu\n",
259			len, clc_len, command, mid);
260
261		return 1;
262	}
263	return 0;
264}
265
266/*
267 * The size of the variable area depends on the offset and length fields
268 * located in different fields for various SMB2 responses. SMB2 responses
269 * with no variable length info, show an offset of zero for the offset field.
270 */
271static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
272	/* SMB2_NEGOTIATE */ true,
273	/* SMB2_SESSION_SETUP */ true,
274	/* SMB2_LOGOFF */ false,
275	/* SMB2_TREE_CONNECT */	false,
276	/* SMB2_TREE_DISCONNECT */ false,
277	/* SMB2_CREATE */ true,
278	/* SMB2_CLOSE */ false,
279	/* SMB2_FLUSH */ false,
280	/* SMB2_READ */	true,
281	/* SMB2_WRITE */ false,
282	/* SMB2_LOCK */	false,
283	/* SMB2_IOCTL */ true,
284	/* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
285	/* SMB2_ECHO */ false,
286	/* SMB2_QUERY_DIRECTORY */ true,
287	/* SMB2_CHANGE_NOTIFY */ true,
288	/* SMB2_QUERY_INFO */ true,
289	/* SMB2_SET_INFO */ false,
290	/* SMB2_OPLOCK_BREAK */ false
291};
292
293/*
294 * Returns the pointer to the beginning of the data area. Length of the data
295 * area and the offset to it (from the beginning of the smb are also returned.
296 */
297char *
298smb2_get_data_area_len(int *off, int *len, struct smb2_sync_hdr *shdr)
299{
300	*off = 0;
301	*len = 0;
302
303	/* error responses do not have data area */
304	if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
305	    (((struct smb2_err_rsp *)shdr)->StructureSize) ==
306						SMB2_ERROR_STRUCTURE_SIZE2)
307		return NULL;
308
309	/*
310	 * Following commands have data areas so we have to get the location
311	 * of the data buffer offset and data buffer length for the particular
312	 * command.
313	 */
314	switch (shdr->Command) {
315	case SMB2_NEGOTIATE:
316		*off = le16_to_cpu(
317		  ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
318		*len = le16_to_cpu(
319		  ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
320		break;
321	case SMB2_SESSION_SETUP:
322		*off = le16_to_cpu(
323		  ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
324		*len = le16_to_cpu(
325		  ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
326		break;
327	case SMB2_CREATE:
328		*off = le32_to_cpu(
329		    ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
330		*len = le32_to_cpu(
331		    ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
332		break;
333	case SMB2_QUERY_INFO:
334		*off = le16_to_cpu(
335		    ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
336		*len = le32_to_cpu(
337		    ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
338		break;
339	case SMB2_READ:
340		/* TODO: is this a bug ? */
341		*off = ((struct smb2_read_rsp *)shdr)->DataOffset;
342		*len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
343		break;
344	case SMB2_QUERY_DIRECTORY:
345		*off = le16_to_cpu(
346		  ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
347		*len = le32_to_cpu(
348		  ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
349		break;
350	case SMB2_IOCTL:
351		*off = le32_to_cpu(
352		  ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
353		*len = le32_to_cpu(
354		  ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
355		break;
356	case SMB2_CHANGE_NOTIFY:
357		*off = le16_to_cpu(
358		  ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
359		*len = le32_to_cpu(
360		  ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
361		break;
362	default:
363		cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
364		break;
365	}
366
367	/*
368	 * Invalid length or offset probably means data area is invalid, but
369	 * we have little choice but to ignore the data area in this case.
370	 */
371	if (*off > 4096) {
372		cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
373		*len = 0;
374		*off = 0;
375	} else if (*off < 0) {
376		cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
377			 *off);
378		*off = 0;
379		*len = 0;
380	} else if (*len < 0) {
381		cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
382			 *len);
383		*len = 0;
384	} else if (*len > 128 * 1024) {
385		cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
386		*len = 0;
387	}
388
389	/* return pointer to beginning of data area, ie offset from SMB start */
390	if ((*off != 0) && (*len != 0))
391		return (char *)shdr + *off;
392	else
393		return NULL;
394}
395
396/*
397 * Calculate the size of the SMB message based on the fixed header
398 * portion, the number of word parameters and the data portion of the message.
399 */
400unsigned int
401smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
402{
403	struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)buf;
404	struct smb2_sync_hdr *shdr = &pdu->sync_hdr;
405	int offset; /* the offset from the beginning of SMB to data area */
406	int data_length; /* the length of the variable length data area */
407	/* Structure Size has already been checked to make sure it is 64 */
408	int len = le16_to_cpu(shdr->StructureSize);
409
410	/*
411	 * StructureSize2, ie length of fixed parameter area has already
412	 * been checked to make sure it is the correct length.
413	 */
414	len += le16_to_cpu(pdu->StructureSize2);
415
416	if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
417		goto calc_size_exit;
418
419	smb2_get_data_area_len(&offset, &data_length, shdr);
420	cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
421
422	if (data_length > 0) {
423		/*
424		 * Check to make sure that data area begins after fixed area,
425		 * Note that last byte of the fixed area is part of data area
426		 * for some commands, typically those with odd StructureSize,
427		 * so we must add one to the calculation.
428		 */
429		if (offset + 1 < len) {
430			cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
431				 offset + 1, len);
432			data_length = 0;
433		} else {
434			len = offset + data_length;
435		}
436	}
437calc_size_exit:
438	cifs_dbg(FYI, "SMB2 len %d\n", len);
439	return len;
440}
441
442/* Note: caller must free return buffer */
443__le16 *
444cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
445{
446	int len;
447	const char *start_of_path;
448	__le16 *to;
449	int map_type;
450
451	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
452		map_type = SFM_MAP_UNI_RSVD;
453	else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
454		map_type = SFU_MAP_UNI_RSVD;
455	else
456		map_type = NO_MAP_UNI_RSVD;
457
458	/* Windows doesn't allow paths beginning with \ */
459	if (from[0] == '\\')
460		start_of_path = from + 1;
461
462	/* SMB311 POSIX extensions paths do not include leading slash */
463	else if (cifs_sb_master_tlink(cifs_sb) &&
464		 cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
465		 (from[0] == '/')) {
466		start_of_path = from + 1;
467	} else
468		start_of_path = from;
469
470	to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
471				   cifs_sb->local_nls, map_type);
472	return to;
473}
474
475__le32
476smb2_get_lease_state(struct cifsInodeInfo *cinode)
477{
478	__le32 lease = 0;
479
480	if (CIFS_CACHE_WRITE(cinode))
481		lease |= SMB2_LEASE_WRITE_CACHING;
482	if (CIFS_CACHE_HANDLE(cinode))
483		lease |= SMB2_LEASE_HANDLE_CACHING;
484	if (CIFS_CACHE_READ(cinode))
485		lease |= SMB2_LEASE_READ_CACHING;
486	return lease;
487}
488
489struct smb2_lease_break_work {
490	struct work_struct lease_break;
491	struct tcon_link *tlink;
492	__u8 lease_key[16];
493	__le32 lease_state;
494};
495
496static void
497cifs_ses_oplock_break(struct work_struct *work)
498{
499	struct smb2_lease_break_work *lw = container_of(work,
500				struct smb2_lease_break_work, lease_break);
501	int rc = 0;
502
503	rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
504			      lw->lease_state);
505
506	cifs_dbg(FYI, "Lease release rc %d\n", rc);
507	cifs_put_tlink(lw->tlink);
508	kfree(lw);
509}
510
511static void
512smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
513			      __le32 new_lease_state)
514{
515	struct smb2_lease_break_work *lw;
516
517	lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
518	if (!lw) {
519		cifs_put_tlink(tlink);
520		return;
521	}
522
523	INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
524	lw->tlink = tlink;
525	lw->lease_state = new_lease_state;
526	memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
527	queue_work(cifsiod_wq, &lw->lease_break);
528}
529
530static bool
531smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
532{
533	__u8 lease_state;
534	struct list_head *tmp;
535	struct cifsFileInfo *cfile;
536	struct cifsInodeInfo *cinode;
537	int ack_req = le32_to_cpu(rsp->Flags &
538				  SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
539
540	lease_state = le32_to_cpu(rsp->NewLeaseState);
541
542	list_for_each(tmp, &tcon->openFileList) {
543		cfile = list_entry(tmp, struct cifsFileInfo, tlist);
544		cinode = CIFS_I(d_inode(cfile->dentry));
545
546		if (memcmp(cinode->lease_key, rsp->LeaseKey,
547							SMB2_LEASE_KEY_SIZE))
548			continue;
549
550		cifs_dbg(FYI, "found in the open list\n");
551		cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
552			 lease_state);
553
554		if (ack_req)
555			cfile->oplock_break_cancelled = false;
556		else
557			cfile->oplock_break_cancelled = true;
558
559		set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
560
561		cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
562		cfile->oplock_level = lease_state;
563
564		cifs_queue_oplock_break(cfile);
565		return true;
566	}
567
568	return false;
569}
570
571static struct cifs_pending_open *
572smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
573				  struct smb2_lease_break *rsp)
574{
575	__u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
576	int ack_req = le32_to_cpu(rsp->Flags &
577				  SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
578	struct cifs_pending_open *open;
579	struct cifs_pending_open *found = NULL;
580
581	list_for_each_entry(open, &tcon->pending_opens, olist) {
582		if (memcmp(open->lease_key, rsp->LeaseKey,
583			   SMB2_LEASE_KEY_SIZE))
584			continue;
585
586		if (!found && ack_req) {
587			found = open;
588		}
589
590		cifs_dbg(FYI, "found in the pending open list\n");
591		cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
592			 lease_state);
593
594		open->oplock = lease_state;
595	}
596
597	return found;
598}
599
600static bool
601smb2_is_valid_lease_break(char *buffer)
602{
603	struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
604	struct list_head *tmp, *tmp1, *tmp2;
605	struct TCP_Server_Info *server;
606	struct cifs_ses *ses;
607	struct cifs_tcon *tcon;
608	struct cifs_pending_open *open;
609
610	cifs_dbg(FYI, "Checking for lease break\n");
611
612	/* look up tcon based on tid & uid */
613	spin_lock(&cifs_tcp_ses_lock);
614	list_for_each(tmp, &cifs_tcp_ses_list) {
615		server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
616
617		list_for_each(tmp1, &server->smb_ses_list) {
618			ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
619
620			list_for_each(tmp2, &ses->tcon_list) {
621				tcon = list_entry(tmp2, struct cifs_tcon,
622						  tcon_list);
623				spin_lock(&tcon->open_file_lock);
624				cifs_stats_inc(
625				    &tcon->stats.cifs_stats.num_oplock_brks);
626				if (smb2_tcon_has_lease(tcon, rsp)) {
627					spin_unlock(&tcon->open_file_lock);
628					spin_unlock(&cifs_tcp_ses_lock);
629					return true;
630				}
631				open = smb2_tcon_find_pending_open_lease(tcon,
632									 rsp);
633				if (open) {
634					__u8 lease_key[SMB2_LEASE_KEY_SIZE];
635					struct tcon_link *tlink;
636
637					tlink = cifs_get_tlink(open->tlink);
638					memcpy(lease_key, open->lease_key,
639					       SMB2_LEASE_KEY_SIZE);
640					spin_unlock(&tcon->open_file_lock);
641					spin_unlock(&cifs_tcp_ses_lock);
642					smb2_queue_pending_open_break(tlink,
643								      lease_key,
644								      rsp->NewLeaseState);
645					return true;
646				}
647				spin_unlock(&tcon->open_file_lock);
648
649				if (tcon->crfid.is_valid &&
650				    !memcmp(rsp->LeaseKey,
651					    tcon->crfid.fid->lease_key,
652					    SMB2_LEASE_KEY_SIZE)) {
653					INIT_WORK(&tcon->crfid.lease_break,
654						  smb2_cached_lease_break);
655					queue_work(cifsiod_wq,
656						   &tcon->crfid.lease_break);
657					spin_unlock(&cifs_tcp_ses_lock);
658					return true;
659				}
660			}
661		}
662	}
663	spin_unlock(&cifs_tcp_ses_lock);
664	cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
665	return false;
666}
667
668bool
669smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
670{
671	struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
672	struct list_head *tmp, *tmp1, *tmp2;
673	struct cifs_ses *ses;
674	struct cifs_tcon *tcon;
675	struct cifsInodeInfo *cinode;
676	struct cifsFileInfo *cfile;
677
678	cifs_dbg(FYI, "Checking for oplock break\n");
679
680	if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
681		return false;
682
683	if (rsp->StructureSize !=
684				smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
685		if (le16_to_cpu(rsp->StructureSize) == 44)
686			return smb2_is_valid_lease_break(buffer);
687		else
688			return false;
689	}
690
691	cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
692
693	/* look up tcon based on tid & uid */
694	spin_lock(&cifs_tcp_ses_lock);
695	list_for_each(tmp, &server->smb_ses_list) {
696		ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
697
698		list_for_each(tmp1, &ses->tcon_list) {
699			tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
700
701			spin_lock(&tcon->open_file_lock);
702			list_for_each(tmp2, &tcon->openFileList) {
703				cfile = list_entry(tmp2, struct cifsFileInfo,
704						     tlist);
705				if (rsp->PersistentFid !=
706				    cfile->fid.persistent_fid ||
707				    rsp->VolatileFid !=
708				    cfile->fid.volatile_fid)
709					continue;
710
711				cifs_dbg(FYI, "file id match, oplock break\n");
712				cifs_stats_inc(
713				    &tcon->stats.cifs_stats.num_oplock_brks);
714				cinode = CIFS_I(d_inode(cfile->dentry));
715				spin_lock(&cfile->file_info_lock);
716				if (!CIFS_CACHE_WRITE(cinode) &&
717				    rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
718					cfile->oplock_break_cancelled = true;
719				else
720					cfile->oplock_break_cancelled = false;
721
722				set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
723					&cinode->flags);
724
725				cfile->oplock_epoch = 0;
726				cfile->oplock_level = rsp->OplockLevel;
727
728				spin_unlock(&cfile->file_info_lock);
729
730				cifs_queue_oplock_break(cfile);
731
732				spin_unlock(&tcon->open_file_lock);
733				spin_unlock(&cifs_tcp_ses_lock);
734				return true;
735			}
736			spin_unlock(&tcon->open_file_lock);
737		}
738	}
739	spin_unlock(&cifs_tcp_ses_lock);
740	cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
741	return false;
742}
743
744void
745smb2_cancelled_close_fid(struct work_struct *work)
746{
747	struct close_cancelled_open *cancelled = container_of(work,
748					struct close_cancelled_open, work);
749	struct cifs_tcon *tcon = cancelled->tcon;
750	int rc;
751
752	if (cancelled->mid)
753		cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llx\n",
754			      cancelled->mid);
755	else
756		cifs_tcon_dbg(VFS, "Close interrupted close\n");
757
758	rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
759			cancelled->fid.volatile_fid);
760	if (rc)
761		cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
762
763	cifs_put_tcon(tcon);
764	kfree(cancelled);
765}
766
767/*
768 * Caller should already has an extra reference to @tcon
769 * This function is used to queue work to close a handle to prevent leaks
770 * on the server.
771 * We handle two cases. If an open was interrupted after we sent the
772 * SMB2_CREATE to the server but before we processed the reply, and second
773 * if a close was interrupted before we sent the SMB2_CLOSE to the server.
774 */
775static int
776__smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
777			    __u64 persistent_fid, __u64 volatile_fid)
778{
779	struct close_cancelled_open *cancelled;
780
781	cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
782	if (!cancelled)
783		return -ENOMEM;
784
785	cancelled->fid.persistent_fid = persistent_fid;
786	cancelled->fid.volatile_fid = volatile_fid;
787	cancelled->tcon = tcon;
788	cancelled->cmd = cmd;
789	cancelled->mid = mid;
790	INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
791	WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
792
793	return 0;
794}
795
796int
797smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
798			    __u64 volatile_fid)
799{
800	int rc;
801
802	cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
803	spin_lock(&cifs_tcp_ses_lock);
804	if (tcon->tc_count <= 0) {
805		struct TCP_Server_Info *server = NULL;
806
807		WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
808		spin_unlock(&cifs_tcp_ses_lock);
809
810		if (tcon->ses)
811			server = tcon->ses->server;
812
813		cifs_server_dbg(FYI, "tid=%u: tcon is closing, skipping async close retry of fid %llu %llu\n",
814				tcon->tid, persistent_fid, volatile_fid);
815
816		return 0;
817	}
818	tcon->tc_count++;
819	spin_unlock(&cifs_tcp_ses_lock);
820
821	rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
822					 persistent_fid, volatile_fid);
823	if (rc)
824		cifs_put_tcon(tcon);
825
826	return rc;
827}
828
829int
830smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
831{
832	struct smb2_sync_hdr *sync_hdr = (struct smb2_sync_hdr *)buffer;
833	struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
834	struct cifs_tcon *tcon;
835	int rc;
836
837	if (sync_hdr->Command != SMB2_CREATE ||
838	    sync_hdr->Status != STATUS_SUCCESS)
839		return 0;
840
841	tcon = smb2_find_smb_tcon(server, sync_hdr->SessionId,
842				  sync_hdr->TreeId);
843	if (!tcon)
844		return -ENOENT;
845
846	rc = __smb2_handle_cancelled_cmd(tcon,
847					 le16_to_cpu(sync_hdr->Command),
848					 le64_to_cpu(sync_hdr->MessageId),
849					 rsp->PersistentFileId,
850					 rsp->VolatileFileId);
851	if (rc)
852		cifs_put_tcon(tcon);
853
854	return rc;
855}
856
857/**
858 * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
859 *
860 * Assumes @iov does not contain the rfc1002 length and iov[0] has the
861 * SMB2 header.
862 */
863int
864smb311_update_preauth_hash(struct cifs_ses *ses, struct kvec *iov, int nvec)
865{
866	int i, rc;
867	struct sdesc *d;
868	struct smb2_sync_hdr *hdr;
869	struct TCP_Server_Info *server = cifs_ses_server(ses);
870
871	hdr = (struct smb2_sync_hdr *)iov[0].iov_base;
872	/* neg prot are always taken */
873	if (hdr->Command == SMB2_NEGOTIATE)
874		goto ok;
875
876	/*
877	 * If we process a command which wasn't a negprot it means the
878	 * neg prot was already done, so the server dialect was set
879	 * and we can test it. Preauth requires 3.1.1 for now.
880	 */
881	if (server->dialect != SMB311_PROT_ID)
882		return 0;
883
884	if (hdr->Command != SMB2_SESSION_SETUP)
885		return 0;
886
887	/* skip last sess setup response */
888	if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
889	    && (hdr->Status == NT_STATUS_OK
890		|| (hdr->Status !=
891		    cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
892		return 0;
893
894ok:
895	rc = smb311_crypto_shash_allocate(server);
896	if (rc)
897		return rc;
898
899	d = server->secmech.sdescsha512;
900	rc = crypto_shash_init(&d->shash);
901	if (rc) {
902		cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
903		return rc;
904	}
905
906	rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
907				 SMB2_PREAUTH_HASH_SIZE);
908	if (rc) {
909		cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
910		return rc;
911	}
912
913	for (i = 0; i < nvec; i++) {
914		rc = crypto_shash_update(&d->shash,
915					 iov[i].iov_base, iov[i].iov_len);
916		if (rc) {
917			cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
918				 __func__);
919			return rc;
920		}
921	}
922
923	rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
924	if (rc) {
925		cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
926			 __func__);
927		return rc;
928	}
929
930	return 0;
931}