Merge tag 'timers-core-2024-01-21' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-block.git] / fs / smb / client / smb2misc.c
1 // SPDX-License-Identifier: LGPL-2.1
2 /*
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  */
10 #include <linux/ctype.h>
11 #include "cifsglob.h"
12 #include "cifsproto.h"
13 #include "smb2proto.h"
14 #include "cifs_debug.h"
15 #include "cifs_unicode.h"
16 #include "smb2status.h"
17 #include "smb2glob.h"
18 #include "nterr.h"
19 #include "cached_dir.h"
20
21 static int
22 check_smb2_hdr(struct smb2_hdr *shdr, __u64 mid)
23 {
24         __u64 wire_mid = le64_to_cpu(shdr->MessageId);
25
26         /*
27          * Make sure that this really is an SMB, that it is a response,
28          * and that the message ids match.
29          */
30         if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
31             (mid == wire_mid)) {
32                 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
33                         return 0;
34                 else {
35                         /* only one valid case where server sends us request */
36                         if (shdr->Command == SMB2_OPLOCK_BREAK)
37                                 return 0;
38                         else
39                                 cifs_dbg(VFS, "Received Request not response\n");
40                 }
41         } else { /* bad signature or mid */
42                 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
43                         cifs_dbg(VFS, "Bad protocol string signature header %x\n",
44                                  le32_to_cpu(shdr->ProtocolId));
45                 if (mid != wire_mid)
46                         cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
47                                  mid, wire_mid);
48         }
49         cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
50         return 1;
51 }
52
53 /*
54  *  The following table defines the expected "StructureSize" of SMB2 responses
55  *  in order by SMB2 command.  This is similar to "wct" in SMB/CIFS responses.
56  *
57  *  Note that commands are defined in smb2pdu.h in le16 but the array below is
58  *  indexed by command in host byte order
59  */
60 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
61         /* SMB2_NEGOTIATE */ cpu_to_le16(65),
62         /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
63         /* SMB2_LOGOFF */ cpu_to_le16(4),
64         /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
65         /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
66         /* SMB2_CREATE */ cpu_to_le16(89),
67         /* SMB2_CLOSE */ cpu_to_le16(60),
68         /* SMB2_FLUSH */ cpu_to_le16(4),
69         /* SMB2_READ */ cpu_to_le16(17),
70         /* SMB2_WRITE */ cpu_to_le16(17),
71         /* SMB2_LOCK */ cpu_to_le16(4),
72         /* SMB2_IOCTL */ cpu_to_le16(49),
73         /* BB CHECK this ... not listed in documentation */
74         /* SMB2_CANCEL */ cpu_to_le16(0),
75         /* SMB2_ECHO */ cpu_to_le16(4),
76         /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
77         /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
78         /* SMB2_QUERY_INFO */ cpu_to_le16(9),
79         /* SMB2_SET_INFO */ cpu_to_le16(2),
80         /* BB FIXME can also be 44 for lease break */
81         /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
82 };
83
84 #define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_hdr) + sizeof(struct smb2_negotiate_rsp))
85
86 static __u32 get_neg_ctxt_len(struct smb2_hdr *hdr, __u32 len,
87                               __u32 non_ctxlen)
88 {
89         __u16 neg_count;
90         __u32 nc_offset, size_of_pad_before_neg_ctxts;
91         struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
92
93         /* Negotiate contexts are only valid for latest dialect SMB3.11 */
94         neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
95         if ((neg_count == 0) ||
96            (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
97                 return 0;
98
99         /*
100          * if SPNEGO blob present (ie the RFC2478 GSS info which indicates
101          * which security mechanisms the server supports) make sure that
102          * the negotiate contexts start after it
103          */
104         nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
105         /*
106          * non_ctxlen is at least shdr->StructureSize + pdu->StructureSize2
107          * and the latter is 1 byte bigger than the fix-sized area of the
108          * NEGOTIATE response
109          */
110         if (nc_offset + 1 < non_ctxlen) {
111                 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
112                 return 0;
113         } else if (nc_offset + 1 == non_ctxlen) {
114                 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
115                 size_of_pad_before_neg_ctxts = 0;
116         } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE + 1)
117                 /* has padding, but no SPNEGO blob */
118                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
119         else
120                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
121
122         /* Verify that at least minimal negotiate contexts fit within frame */
123         if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
124                 pr_warn_once("negotiate context goes beyond end\n");
125                 return 0;
126         }
127
128         cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
129                 len - nc_offset, size_of_pad_before_neg_ctxts);
130
131         /* length of negcontexts including pad from end of sec blob to them */
132         return (len - nc_offset) + size_of_pad_before_neg_ctxts;
133 }
134
135 int
136 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
137 {
138         struct TCP_Server_Info *pserver;
139         struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
140         struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
141         int hdr_size = sizeof(struct smb2_hdr);
142         int pdu_size = sizeof(struct smb2_pdu);
143         int command;
144         __u32 calc_len; /* calculated length */
145         __u64 mid;
146
147         /* If server is a channel, select the primary channel */
148         pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
149
150         /*
151          * Add function to do table lookup of StructureSize by command
152          * ie Validate the wct via smb2_struct_sizes table above
153          */
154         if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
155                 struct smb2_transform_hdr *thdr =
156                         (struct smb2_transform_hdr *)buf;
157                 struct cifs_ses *ses = NULL;
158                 struct cifs_ses *iter;
159
160                 /* decrypt frame now that it is completely read in */
161                 spin_lock(&cifs_tcp_ses_lock);
162                 list_for_each_entry(iter, &pserver->smb_ses_list, smb_ses_list) {
163                         if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
164                                 ses = iter;
165                                 break;
166                         }
167                 }
168                 spin_unlock(&cifs_tcp_ses_lock);
169                 if (!ses) {
170                         cifs_dbg(VFS, "no decryption - session id not found\n");
171                         return 1;
172                 }
173         }
174
175         mid = le64_to_cpu(shdr->MessageId);
176         if (check_smb2_hdr(shdr, mid))
177                 return 1;
178
179         if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
180                 cifs_dbg(VFS, "Invalid structure size %u\n",
181                          le16_to_cpu(shdr->StructureSize));
182                 return 1;
183         }
184
185         command = le16_to_cpu(shdr->Command);
186         if (command >= NUMBER_OF_SMB2_COMMANDS) {
187                 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
188                 return 1;
189         }
190
191         if (len < pdu_size) {
192                 if ((len >= hdr_size)
193                     && (shdr->Status != 0)) {
194                         pdu->StructureSize2 = 0;
195                         /*
196                          * As with SMB/CIFS, on some error cases servers may
197                          * not return wct properly
198                          */
199                         return 0;
200                 } else {
201                         cifs_dbg(VFS, "Length less than SMB header size\n");
202                 }
203                 return 1;
204         }
205         if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
206                 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
207                          mid);
208                 return 1;
209         }
210
211         if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
212                 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
213                     pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2_LE)) {
214                         /* error packets have 9 byte structure size */
215                         cifs_dbg(VFS, "Invalid response size %u for command %d\n",
216                                  le16_to_cpu(pdu->StructureSize2), command);
217                         return 1;
218                 } else if (command == SMB2_OPLOCK_BREAK_HE
219                            && (shdr->Status == 0)
220                            && (le16_to_cpu(pdu->StructureSize2) != 44)
221                            && (le16_to_cpu(pdu->StructureSize2) != 36)) {
222                         /* special case for SMB2.1 lease break message */
223                         cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
224                                  le16_to_cpu(pdu->StructureSize2));
225                         return 1;
226                 }
227         }
228
229         calc_len = smb2_calc_size(buf);
230
231         /* For SMB2_IOCTL, OutputOffset and OutputLength are optional, so might
232          * be 0, and not a real miscalculation */
233         if (command == SMB2_IOCTL_HE && calc_len == 0)
234                 return 0;
235
236         if (command == SMB2_NEGOTIATE_HE)
237                 calc_len += get_neg_ctxt_len(shdr, len, calc_len);
238
239         if (len != calc_len) {
240                 /* create failed on symlink */
241                 if (command == SMB2_CREATE_HE &&
242                     shdr->Status == STATUS_STOPPED_ON_SYMLINK)
243                         return 0;
244                 /* Windows 7 server returns 24 bytes more */
245                 if (calc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
246                         return 0;
247                 /* server can return one byte more due to implied bcc[0] */
248                 if (calc_len == len + 1)
249                         return 0;
250
251                 /*
252                  * Some windows servers (win2016) will pad also the final
253                  * PDU in a compound to 8 bytes.
254                  */
255                 if (ALIGN(calc_len, 8) == len)
256                         return 0;
257
258                 /*
259                  * MacOS server pads after SMB2.1 write response with 3 bytes
260                  * of junk. Other servers match RFC1001 len to actual
261                  * SMB2/SMB3 frame length (header + smb2 response specific data)
262                  * Some windows servers also pad up to 8 bytes when compounding.
263                  */
264                 if (calc_len < len)
265                         return 0;
266
267                 /* Only log a message if len was really miscalculated */
268                 if (unlikely(cifsFYI))
269                         cifs_dbg(FYI, "Server response too short: calculated "
270                                  "length %u doesn't match read length %u (cmd=%d, mid=%llu)\n",
271                                  calc_len, len, command, mid);
272                 else
273                         pr_warn("Server response too short: calculated length "
274                                 "%u doesn't match read length %u (cmd=%d, mid=%llu)\n",
275                                 calc_len, len, command, mid);
276
277                 return 1;
278         }
279         return 0;
280 }
281
282 /*
283  * The size of the variable area depends on the offset and length fields
284  * located in different fields for various SMB2 responses. SMB2 responses
285  * with no variable length info, show an offset of zero for the offset field.
286  */
287 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
288         /* SMB2_NEGOTIATE */ true,
289         /* SMB2_SESSION_SETUP */ true,
290         /* SMB2_LOGOFF */ false,
291         /* SMB2_TREE_CONNECT */ false,
292         /* SMB2_TREE_DISCONNECT */ false,
293         /* SMB2_CREATE */ true,
294         /* SMB2_CLOSE */ false,
295         /* SMB2_FLUSH */ false,
296         /* SMB2_READ */ true,
297         /* SMB2_WRITE */ false,
298         /* SMB2_LOCK */ false,
299         /* SMB2_IOCTL */ true,
300         /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
301         /* SMB2_ECHO */ false,
302         /* SMB2_QUERY_DIRECTORY */ true,
303         /* SMB2_CHANGE_NOTIFY */ true,
304         /* SMB2_QUERY_INFO */ true,
305         /* SMB2_SET_INFO */ false,
306         /* SMB2_OPLOCK_BREAK */ false
307 };
308
309 /*
310  * Returns the pointer to the beginning of the data area. Length of the data
311  * area and the offset to it (from the beginning of the smb are also returned.
312  */
313 char *
314 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
315 {
316         const int max_off = 4096;
317         const int max_len = 128 * 1024;
318
319         *off = 0;
320         *len = 0;
321
322         /* error responses do not have data area */
323         if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
324             (((struct smb2_err_rsp *)shdr)->StructureSize) ==
325                                                 SMB2_ERROR_STRUCTURE_SIZE2_LE)
326                 return NULL;
327
328         /*
329          * Following commands have data areas so we have to get the location
330          * of the data buffer offset and data buffer length for the particular
331          * command.
332          */
333         switch (shdr->Command) {
334         case SMB2_NEGOTIATE:
335                 *off = le16_to_cpu(
336                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
337                 *len = le16_to_cpu(
338                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
339                 break;
340         case SMB2_SESSION_SETUP:
341                 *off = le16_to_cpu(
342                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
343                 *len = le16_to_cpu(
344                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
345                 break;
346         case SMB2_CREATE:
347                 *off = le32_to_cpu(
348                     ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
349                 *len = le32_to_cpu(
350                     ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
351                 break;
352         case SMB2_QUERY_INFO:
353                 *off = le16_to_cpu(
354                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
355                 *len = le32_to_cpu(
356                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
357                 break;
358         case SMB2_READ:
359                 /* TODO: is this a bug ? */
360                 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
361                 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
362                 break;
363         case SMB2_QUERY_DIRECTORY:
364                 *off = le16_to_cpu(
365                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
366                 *len = le32_to_cpu(
367                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
368                 break;
369         case SMB2_IOCTL:
370                 *off = le32_to_cpu(
371                   ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
372                 *len = le32_to_cpu(
373                   ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
374                 break;
375         case SMB2_CHANGE_NOTIFY:
376                 *off = le16_to_cpu(
377                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
378                 *len = le32_to_cpu(
379                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
380                 break;
381         default:
382                 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
383                 break;
384         }
385
386         /*
387          * Invalid length or offset probably means data area is invalid, but
388          * we have little choice but to ignore the data area in this case.
389          */
390         if (unlikely(*off < 0 || *off > max_off ||
391                      *len < 0 || *len > max_len)) {
392                 cifs_dbg(VFS, "%s: invalid data area (off=%d len=%d)\n",
393                          __func__, *off, *len);
394                 *off = 0;
395                 *len = 0;
396         } else if (*off == 0) {
397                 *len = 0;
398         }
399
400         /* return pointer to beginning of data area, ie offset from SMB start */
401         if (*off > 0 && *len > 0)
402                 return (char *)shdr + *off;
403         return NULL;
404 }
405
406 /*
407  * Calculate the size of the SMB message based on the fixed header
408  * portion, the number of word parameters and the data portion of the message.
409  */
410 unsigned int
411 smb2_calc_size(void *buf)
412 {
413         struct smb2_pdu *pdu = buf;
414         struct smb2_hdr *shdr = &pdu->hdr;
415         int offset; /* the offset from the beginning of SMB to data area */
416         int data_length; /* the length of the variable length data area */
417         /* Structure Size has already been checked to make sure it is 64 */
418         int len = le16_to_cpu(shdr->StructureSize);
419
420         /*
421          * StructureSize2, ie length of fixed parameter area has already
422          * been checked to make sure it is the correct length.
423          */
424         len += le16_to_cpu(pdu->StructureSize2);
425
426         if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
427                 goto calc_size_exit;
428
429         smb2_get_data_area_len(&offset, &data_length, shdr);
430         cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
431
432         if (data_length > 0) {
433                 /*
434                  * Check to make sure that data area begins after fixed area,
435                  * Note that last byte of the fixed area is part of data area
436                  * for some commands, typically those with odd StructureSize,
437                  * so we must add one to the calculation.
438                  */
439                 if (offset + 1 < len) {
440                         cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
441                                  offset + 1, len);
442                         data_length = 0;
443                 } else {
444                         len = offset + data_length;
445                 }
446         }
447 calc_size_exit:
448         cifs_dbg(FYI, "SMB2 len %d\n", len);
449         return len;
450 }
451
452 /* Note: caller must free return buffer */
453 __le16 *
454 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
455 {
456         int len;
457         const char *start_of_path;
458         __le16 *to;
459         int map_type;
460
461         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
462                 map_type = SFM_MAP_UNI_RSVD;
463         else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
464                 map_type = SFU_MAP_UNI_RSVD;
465         else
466                 map_type = NO_MAP_UNI_RSVD;
467
468         /* Windows doesn't allow paths beginning with \ */
469         if (from[0] == '\\')
470                 start_of_path = from + 1;
471
472         /* SMB311 POSIX extensions paths do not include leading slash */
473         else if (cifs_sb_master_tlink(cifs_sb) &&
474                  cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
475                  (from[0] == '/')) {
476                 start_of_path = from + 1;
477         } else
478                 start_of_path = from;
479
480         to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
481                                    cifs_sb->local_nls, map_type);
482         return to;
483 }
484
485 __le32
486 smb2_get_lease_state(struct cifsInodeInfo *cinode)
487 {
488         __le32 lease = 0;
489
490         if (CIFS_CACHE_WRITE(cinode))
491                 lease |= SMB2_LEASE_WRITE_CACHING_LE;
492         if (CIFS_CACHE_HANDLE(cinode))
493                 lease |= SMB2_LEASE_HANDLE_CACHING_LE;
494         if (CIFS_CACHE_READ(cinode))
495                 lease |= SMB2_LEASE_READ_CACHING_LE;
496         return lease;
497 }
498
499 struct smb2_lease_break_work {
500         struct work_struct lease_break;
501         struct tcon_link *tlink;
502         __u8 lease_key[16];
503         __le32 lease_state;
504 };
505
506 static void
507 cifs_ses_oplock_break(struct work_struct *work)
508 {
509         struct smb2_lease_break_work *lw = container_of(work,
510                                 struct smb2_lease_break_work, lease_break);
511         int rc = 0;
512
513         rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
514                               lw->lease_state);
515
516         cifs_dbg(FYI, "Lease release rc %d\n", rc);
517         cifs_put_tlink(lw->tlink);
518         kfree(lw);
519 }
520
521 static void
522 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
523                               __le32 new_lease_state)
524 {
525         struct smb2_lease_break_work *lw;
526
527         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
528         if (!lw) {
529                 cifs_put_tlink(tlink);
530                 return;
531         }
532
533         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
534         lw->tlink = tlink;
535         lw->lease_state = new_lease_state;
536         memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
537         queue_work(cifsiod_wq, &lw->lease_break);
538 }
539
540 static bool
541 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
542 {
543         __u8 lease_state;
544         struct cifsFileInfo *cfile;
545         struct cifsInodeInfo *cinode;
546         int ack_req = le32_to_cpu(rsp->Flags &
547                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
548
549         lease_state = le32_to_cpu(rsp->NewLeaseState);
550
551         list_for_each_entry(cfile, &tcon->openFileList, tlist) {
552                 cinode = CIFS_I(d_inode(cfile->dentry));
553
554                 if (memcmp(cinode->lease_key, rsp->LeaseKey,
555                                                         SMB2_LEASE_KEY_SIZE))
556                         continue;
557
558                 cifs_dbg(FYI, "found in the open list\n");
559                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
560                          lease_state);
561
562                 if (ack_req)
563                         cfile->oplock_break_cancelled = false;
564                 else
565                         cfile->oplock_break_cancelled = true;
566
567                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
568
569                 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
570                 cfile->oplock_level = lease_state;
571
572                 cifs_queue_oplock_break(cfile);
573                 return true;
574         }
575
576         return false;
577 }
578
579 static struct cifs_pending_open *
580 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
581                                   struct smb2_lease_break *rsp)
582 {
583         __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
584         int ack_req = le32_to_cpu(rsp->Flags &
585                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
586         struct cifs_pending_open *open;
587         struct cifs_pending_open *found = NULL;
588
589         list_for_each_entry(open, &tcon->pending_opens, olist) {
590                 if (memcmp(open->lease_key, rsp->LeaseKey,
591                            SMB2_LEASE_KEY_SIZE))
592                         continue;
593
594                 if (!found && ack_req) {
595                         found = open;
596                 }
597
598                 cifs_dbg(FYI, "found in the pending open list\n");
599                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
600                          lease_state);
601
602                 open->oplock = lease_state;
603         }
604
605         return found;
606 }
607
608 static bool
609 smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
610 {
611         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
612         struct TCP_Server_Info *pserver;
613         struct cifs_ses *ses;
614         struct cifs_tcon *tcon;
615         struct cifs_pending_open *open;
616
617         cifs_dbg(FYI, "Checking for lease break\n");
618
619         /* If server is a channel, select the primary channel */
620         pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
621
622         /* look up tcon based on tid & uid */
623         spin_lock(&cifs_tcp_ses_lock);
624         list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
625                 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
626                         spin_lock(&tcon->open_file_lock);
627                         cifs_stats_inc(
628                                        &tcon->stats.cifs_stats.num_oplock_brks);
629                         if (smb2_tcon_has_lease(tcon, rsp)) {
630                                 spin_unlock(&tcon->open_file_lock);
631                                 spin_unlock(&cifs_tcp_ses_lock);
632                                 return true;
633                         }
634                         open = smb2_tcon_find_pending_open_lease(tcon,
635                                                                  rsp);
636                         if (open) {
637                                 __u8 lease_key[SMB2_LEASE_KEY_SIZE];
638                                 struct tcon_link *tlink;
639
640                                 tlink = cifs_get_tlink(open->tlink);
641                                 memcpy(lease_key, open->lease_key,
642                                        SMB2_LEASE_KEY_SIZE);
643                                 spin_unlock(&tcon->open_file_lock);
644                                 spin_unlock(&cifs_tcp_ses_lock);
645                                 smb2_queue_pending_open_break(tlink,
646                                                               lease_key,
647                                                               rsp->NewLeaseState);
648                                 return true;
649                         }
650                         spin_unlock(&tcon->open_file_lock);
651
652                         if (cached_dir_lease_break(tcon, rsp->LeaseKey)) {
653                                 spin_unlock(&cifs_tcp_ses_lock);
654                                 return true;
655                         }
656                 }
657         }
658         spin_unlock(&cifs_tcp_ses_lock);
659         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
660         trace_smb3_lease_not_found(le32_to_cpu(rsp->CurrentLeaseState),
661                                    le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
662                                    le64_to_cpu(rsp->hdr.SessionId),
663                                    *((u64 *)rsp->LeaseKey),
664                                    *((u64 *)&rsp->LeaseKey[8]));
665
666         return false;
667 }
668
669 bool
670 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
671 {
672         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
673         struct TCP_Server_Info *pserver;
674         struct cifs_ses *ses;
675         struct cifs_tcon *tcon;
676         struct cifsInodeInfo *cinode;
677         struct cifsFileInfo *cfile;
678
679         cifs_dbg(FYI, "Checking for oplock break\n");
680
681         if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
682                 return false;
683
684         if (rsp->StructureSize !=
685                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
686                 if (le16_to_cpu(rsp->StructureSize) == 44)
687                         return smb2_is_valid_lease_break(buffer, server);
688                 else
689                         return false;
690         }
691
692         cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
693
694         /* If server is a channel, select the primary channel */
695         pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
696
697         /* look up tcon based on tid & uid */
698         spin_lock(&cifs_tcp_ses_lock);
699         list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
700                 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
701
702                         spin_lock(&tcon->open_file_lock);
703                         list_for_each_entry(cfile, &tcon->openFileList, tlist) {
704                                 if (rsp->PersistentFid !=
705                                     cfile->fid.persistent_fid ||
706                                     rsp->VolatileFid !=
707                                     cfile->fid.volatile_fid)
708                                         continue;
709
710                                 cifs_dbg(FYI, "file id match, oplock break\n");
711                                 cifs_stats_inc(
712                                     &tcon->stats.cifs_stats.num_oplock_brks);
713                                 cinode = CIFS_I(d_inode(cfile->dentry));
714                                 spin_lock(&cfile->file_info_lock);
715                                 if (!CIFS_CACHE_WRITE(cinode) &&
716                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
717                                         cfile->oplock_break_cancelled = true;
718                                 else
719                                         cfile->oplock_break_cancelled = false;
720
721                                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
722                                         &cinode->flags);
723
724                                 cfile->oplock_epoch = 0;
725                                 cfile->oplock_level = rsp->OplockLevel;
726
727                                 spin_unlock(&cfile->file_info_lock);
728
729                                 cifs_queue_oplock_break(cfile);
730
731                                 spin_unlock(&tcon->open_file_lock);
732                                 spin_unlock(&cifs_tcp_ses_lock);
733                                 return true;
734                         }
735                         spin_unlock(&tcon->open_file_lock);
736                 }
737         }
738         spin_unlock(&cifs_tcp_ses_lock);
739         cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
740         trace_smb3_oplock_not_found(0 /* no xid */, rsp->PersistentFid,
741                                   le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
742                                   le64_to_cpu(rsp->hdr.SessionId));
743
744         return true;
745 }
746
747 void
748 smb2_cancelled_close_fid(struct work_struct *work)
749 {
750         struct close_cancelled_open *cancelled = container_of(work,
751                                         struct close_cancelled_open, work);
752         struct cifs_tcon *tcon = cancelled->tcon;
753         int rc;
754
755         if (cancelled->mid)
756                 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
757                               cancelled->mid);
758         else
759                 cifs_tcon_dbg(VFS, "Close interrupted close\n");
760
761         rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
762                         cancelled->fid.volatile_fid);
763         if (rc)
764                 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
765
766         cifs_put_tcon(tcon);
767         kfree(cancelled);
768 }
769
770 /*
771  * Caller should already has an extra reference to @tcon
772  * This function is used to queue work to close a handle to prevent leaks
773  * on the server.
774  * We handle two cases. If an open was interrupted after we sent the
775  * SMB2_CREATE to the server but before we processed the reply, and second
776  * if a close was interrupted before we sent the SMB2_CLOSE to the server.
777  */
778 static int
779 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
780                             __u64 persistent_fid, __u64 volatile_fid)
781 {
782         struct close_cancelled_open *cancelled;
783
784         cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
785         if (!cancelled)
786                 return -ENOMEM;
787
788         cancelled->fid.persistent_fid = persistent_fid;
789         cancelled->fid.volatile_fid = volatile_fid;
790         cancelled->tcon = tcon;
791         cancelled->cmd = cmd;
792         cancelled->mid = mid;
793         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
794         WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
795
796         return 0;
797 }
798
799 int
800 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
801                             __u64 volatile_fid)
802 {
803         int rc;
804
805         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
806         spin_lock(&cifs_tcp_ses_lock);
807         if (tcon->tc_count <= 0) {
808                 struct TCP_Server_Info *server = NULL;
809
810                 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
811                 spin_unlock(&cifs_tcp_ses_lock);
812
813                 if (tcon->ses)
814                         server = tcon->ses->server;
815
816                 cifs_server_dbg(FYI, "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
817                                 tcon->tid, persistent_fid, volatile_fid);
818
819                 return 0;
820         }
821         tcon->tc_count++;
822         spin_unlock(&cifs_tcp_ses_lock);
823
824         rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
825                                          persistent_fid, volatile_fid);
826         if (rc)
827                 cifs_put_tcon(tcon);
828
829         return rc;
830 }
831
832 int
833 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
834 {
835         struct smb2_hdr *hdr = mid->resp_buf;
836         struct smb2_create_rsp *rsp = mid->resp_buf;
837         struct cifs_tcon *tcon;
838         int rc;
839
840         if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || hdr->Command != SMB2_CREATE ||
841             hdr->Status != STATUS_SUCCESS)
842                 return 0;
843
844         tcon = smb2_find_smb_tcon(server, le64_to_cpu(hdr->SessionId),
845                                   le32_to_cpu(hdr->Id.SyncId.TreeId));
846         if (!tcon)
847                 return -ENOENT;
848
849         rc = __smb2_handle_cancelled_cmd(tcon,
850                                          le16_to_cpu(hdr->Command),
851                                          le64_to_cpu(hdr->MessageId),
852                                          rsp->PersistentFileId,
853                                          rsp->VolatileFileId);
854         if (rc)
855                 cifs_put_tcon(tcon);
856
857         return rc;
858 }
859
860 /**
861  * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
862  *
863  * Assumes @iov does not contain the rfc1002 length and iov[0] has the
864  * SMB2 header.
865  *
866  * @ses:        server session structure
867  * @server:     pointer to server info
868  * @iov:        array containing the SMB request we will send to the server
869  * @nvec:       number of array entries for the iov
870  */
871 int
872 smb311_update_preauth_hash(struct cifs_ses *ses, struct TCP_Server_Info *server,
873                            struct kvec *iov, int nvec)
874 {
875         int i, rc;
876         struct smb2_hdr *hdr;
877         struct shash_desc *sha512 = NULL;
878
879         hdr = (struct smb2_hdr *)iov[0].iov_base;
880         /* neg prot are always taken */
881         if (hdr->Command == SMB2_NEGOTIATE)
882                 goto ok;
883
884         /*
885          * If we process a command which wasn't a negprot it means the
886          * neg prot was already done, so the server dialect was set
887          * and we can test it. Preauth requires 3.1.1 for now.
888          */
889         if (server->dialect != SMB311_PROT_ID)
890                 return 0;
891
892         if (hdr->Command != SMB2_SESSION_SETUP)
893                 return 0;
894
895         /* skip last sess setup response */
896         if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
897             && (hdr->Status == NT_STATUS_OK
898                 || (hdr->Status !=
899                     cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
900                 return 0;
901
902 ok:
903         rc = smb311_crypto_shash_allocate(server);
904         if (rc)
905                 return rc;
906
907         sha512 = server->secmech.sha512;
908         rc = crypto_shash_init(sha512);
909         if (rc) {
910                 cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
911                 return rc;
912         }
913
914         rc = crypto_shash_update(sha512, ses->preauth_sha_hash,
915                                  SMB2_PREAUTH_HASH_SIZE);
916         if (rc) {
917                 cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
918                 return rc;
919         }
920
921         for (i = 0; i < nvec; i++) {
922                 rc = crypto_shash_update(sha512, iov[i].iov_base, iov[i].iov_len);
923                 if (rc) {
924                         cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
925                                  __func__);
926                         return rc;
927                 }
928         }
929
930         rc = crypto_shash_final(sha512, ses->preauth_sha_hash);
931         if (rc) {
932                 cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
933                          __func__);
934                 return rc;
935         }
936
937         return 0;
938 }