Merge tag 'v5.9' into next
[linux-2.6-microblaze.git] / fs / cifs / smb2misc.c
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
34 static int
35 check_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  */
73 static 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
97 static __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
131 int
132 smb2_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  */
271 static 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  */
297 char *
298 smb2_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  */
400 unsigned int
401 smb2_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         }
437 calc_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 *
444 cifs_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
476 smb2_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
489 struct 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
496 static void
497 cifs_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
511 static void
512 smb2_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
530 static bool
531 smb2_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
571 static struct cifs_pending_open *
572 smb2_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
600 static bool
601 smb2_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
668 bool
669 smb2_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
744 void
745 smb2_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  */
775 static 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
796 int
797 smb2_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
829 int
830 smb2_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  */
863 int
864 smb311_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
894 ok:
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 }