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1// SPDX-License-Identifier: LGPL-2.1
2/*
3 * fs/cifs/smb2misc.c
4 *
5 * Copyright (C) International Business Machines Corp., 2002,2011
6 * Etersoft, 2012
7 * Author(s): Steve French (sfrench@us.ibm.com)
8 * Pavel Shilovsky (pshilovsky@samba.org) 2012
9 *
10 */
11#include <linux/ctype.h>
12#include "smb2pdu.h"
13#include "cifsglob.h"
14#include "cifsproto.h"
15#include "smb2proto.h"
16#include "cifs_debug.h"
17#include "cifs_unicode.h"
18#include "smb2status.h"
19#include "smb2glob.h"
20#include "nterr.h"
21
22static int
23check_smb2_hdr(struct smb2_sync_hdr *shdr, __u64 mid)
24{
25 __u64 wire_mid = le64_to_cpu(shdr->MessageId);
26
27 /*
28 * Make sure that this really is an SMB, that it is a response,
29 * and that the message ids match.
30 */
31 if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
32 (mid == wire_mid)) {
33 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
34 return 0;
35 else {
36 /* only one valid case where server sends us request */
37 if (shdr->Command == SMB2_OPLOCK_BREAK)
38 return 0;
39 else
40 cifs_dbg(VFS, "Received Request not response\n");
41 }
42 } else { /* bad signature or mid */
43 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
44 cifs_dbg(VFS, "Bad protocol string signature header %x\n",
45 le32_to_cpu(shdr->ProtocolId));
46 if (mid != wire_mid)
47 cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
48 mid, wire_mid);
49 }
50 cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
51 return 1;
52}
53
54/*
55 * The following table defines the expected "StructureSize" of SMB2 responses
56 * in order by SMB2 command. This is similar to "wct" in SMB/CIFS responses.
57 *
58 * Note that commands are defined in smb2pdu.h in le16 but the array below is
59 * indexed by command in host byte order
60 */
61static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
62 /* SMB2_NEGOTIATE */ cpu_to_le16(65),
63 /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
64 /* SMB2_LOGOFF */ cpu_to_le16(4),
65 /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
66 /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
67 /* SMB2_CREATE */ cpu_to_le16(89),
68 /* SMB2_CLOSE */ cpu_to_le16(60),
69 /* SMB2_FLUSH */ cpu_to_le16(4),
70 /* SMB2_READ */ cpu_to_le16(17),
71 /* SMB2_WRITE */ cpu_to_le16(17),
72 /* SMB2_LOCK */ cpu_to_le16(4),
73 /* SMB2_IOCTL */ cpu_to_le16(49),
74 /* BB CHECK this ... not listed in documentation */
75 /* SMB2_CANCEL */ cpu_to_le16(0),
76 /* SMB2_ECHO */ cpu_to_le16(4),
77 /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
78 /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
79 /* SMB2_QUERY_INFO */ cpu_to_le16(9),
80 /* SMB2_SET_INFO */ cpu_to_le16(2),
81 /* BB FIXME can also be 44 for lease break */
82 /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
83};
84
85#define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_sync_hdr) + sizeof(struct smb2_negotiate_rsp))
86
87static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len,
88 __u32 non_ctxlen)
89{
90 __u16 neg_count;
91 __u32 nc_offset, size_of_pad_before_neg_ctxts;
92 struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
93
94 /* Negotiate contexts are only valid for latest dialect SMB3.11 */
95 neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
96 if ((neg_count == 0) ||
97 (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
98 return 0;
99
100 /*
101 * if SPNEGO blob present (ie the RFC2478 GSS info which indicates
102 * which security mechanisms the server supports) make sure that
103 * the negotiate contexts start after it
104 */
105 nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
106 /*
107 * non_ctxlen is at least shdr->StructureSize + pdu->StructureSize2
108 * and the latter is 1 byte bigger than the fix-sized area of the
109 * NEGOTIATE response
110 */
111 if (nc_offset + 1 < non_ctxlen) {
112 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
113 return 0;
114 } else if (nc_offset + 1 == non_ctxlen) {
115 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
116 size_of_pad_before_neg_ctxts = 0;
117 } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE)
118 /* has padding, but no SPNEGO blob */
119 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
120 else
121 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
122
123 /* Verify that at least minimal negotiate contexts fit within frame */
124 if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
125 pr_warn_once("negotiate context goes beyond end\n");
126 return 0;
127 }
128
129 cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
130 len - nc_offset, size_of_pad_before_neg_ctxts);
131
132 /* length of negcontexts including pad from end of sec blob to them */
133 return (len - nc_offset) + size_of_pad_before_neg_ctxts;
134}
135
136int
137smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
138{
139 struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
140 struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)shdr;
141 __u64 mid;
142 __u32 clc_len; /* calculated length */
143 int command;
144 int pdu_size = sizeof(struct smb2_sync_pdu);
145 int hdr_size = sizeof(struct smb2_sync_hdr);
146
147 /*
148 * Add function to do table lookup of StructureSize by command
149 * ie Validate the wct via smb2_struct_sizes table above
150 */
151 if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
152 struct smb2_transform_hdr *thdr =
153 (struct smb2_transform_hdr *)buf;
154 struct cifs_ses *ses = NULL;
155
156 /* decrypt frame now that it is completely read in */
157 spin_lock(&cifs_tcp_ses_lock);
158 list_for_each_entry(ses, &srvr->smb_ses_list, smb_ses_list) {
159 if (ses->Suid == thdr->SessionId)
160 break;
161 }
162 spin_unlock(&cifs_tcp_ses_lock);
163 if (list_entry_is_head(ses, &srvr->smb_ses_list,
164 smb_ses_list)) {
165 cifs_dbg(VFS, "no decryption - session id not found\n");
166 return 1;
167 }
168 }
169
170 mid = le64_to_cpu(shdr->MessageId);
171 if (len < pdu_size) {
172 if ((len >= hdr_size)
173 && (shdr->Status != 0)) {
174 pdu->StructureSize2 = 0;
175 /*
176 * As with SMB/CIFS, on some error cases servers may
177 * not return wct properly
178 */
179 return 0;
180 } else {
181 cifs_dbg(VFS, "Length less than SMB header size\n");
182 }
183 return 1;
184 }
185 if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
186 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
187 mid);
188 return 1;
189 }
190
191 if (check_smb2_hdr(shdr, mid))
192 return 1;
193
194 if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
195 cifs_dbg(VFS, "Invalid structure size %u\n",
196 le16_to_cpu(shdr->StructureSize));
197 return 1;
198 }
199
200 command = le16_to_cpu(shdr->Command);
201 if (command >= NUMBER_OF_SMB2_COMMANDS) {
202 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
203 return 1;
204 }
205
206 if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
207 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
208 pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
209 /* error packets have 9 byte structure size */
210 cifs_dbg(VFS, "Invalid response size %u for command %d\n",
211 le16_to_cpu(pdu->StructureSize2), command);
212 return 1;
213 } else if (command == SMB2_OPLOCK_BREAK_HE
214 && (shdr->Status == 0)
215 && (le16_to_cpu(pdu->StructureSize2) != 44)
216 && (le16_to_cpu(pdu->StructureSize2) != 36)) {
217 /* special case for SMB2.1 lease break message */
218 cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
219 le16_to_cpu(pdu->StructureSize2));
220 return 1;
221 }
222 }
223
224 clc_len = smb2_calc_size(buf, srvr);
225
226 if (shdr->Command == SMB2_NEGOTIATE)
227 clc_len += get_neg_ctxt_len(shdr, len, clc_len);
228
229 if (len != clc_len) {
230 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
231 clc_len, len, mid);
232 /* create failed on symlink */
233 if (command == SMB2_CREATE_HE &&
234 shdr->Status == STATUS_STOPPED_ON_SYMLINK)
235 return 0;
236 /* Windows 7 server returns 24 bytes more */
237 if (clc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
238 return 0;
239 /* server can return one byte more due to implied bcc[0] */
240 if (clc_len == len + 1)
241 return 0;
242
243 /*
244 * Some windows servers (win2016) will pad also the final
245 * PDU in a compound to 8 bytes.
246 */
247 if (((clc_len + 7) & ~7) == len)
248 return 0;
249
250 /*
251 * MacOS server pads after SMB2.1 write response with 3 bytes
252 * of junk. Other servers match RFC1001 len to actual
253 * SMB2/SMB3 frame length (header + smb2 response specific data)
254 * Some windows servers also pad up to 8 bytes when compounding.
255 */
256 if (clc_len < len)
257 return 0;
258
259 pr_warn_once(
260 "srv rsp too short, len %d not %d. cmd:%d mid:%llu\n",
261 len, clc_len, command, mid);
262
263 return 1;
264 }
265 return 0;
266}
267
268/*
269 * The size of the variable area depends on the offset and length fields
270 * located in different fields for various SMB2 responses. SMB2 responses
271 * with no variable length info, show an offset of zero for the offset field.
272 */
273static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
274 /* SMB2_NEGOTIATE */ true,
275 /* SMB2_SESSION_SETUP */ true,
276 /* SMB2_LOGOFF */ false,
277 /* SMB2_TREE_CONNECT */ false,
278 /* SMB2_TREE_DISCONNECT */ false,
279 /* SMB2_CREATE */ true,
280 /* SMB2_CLOSE */ false,
281 /* SMB2_FLUSH */ false,
282 /* SMB2_READ */ true,
283 /* SMB2_WRITE */ false,
284 /* SMB2_LOCK */ false,
285 /* SMB2_IOCTL */ true,
286 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
287 /* SMB2_ECHO */ false,
288 /* SMB2_QUERY_DIRECTORY */ true,
289 /* SMB2_CHANGE_NOTIFY */ true,
290 /* SMB2_QUERY_INFO */ true,
291 /* SMB2_SET_INFO */ false,
292 /* SMB2_OPLOCK_BREAK */ false
293};
294
295/*
296 * Returns the pointer to the beginning of the data area. Length of the data
297 * area and the offset to it (from the beginning of the smb are also returned.
298 */
299char *
300smb2_get_data_area_len(int *off, int *len, struct smb2_sync_hdr *shdr)
301{
302 *off = 0;
303 *len = 0;
304
305 /* error responses do not have data area */
306 if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
307 (((struct smb2_err_rsp *)shdr)->StructureSize) ==
308 SMB2_ERROR_STRUCTURE_SIZE2)
309 return NULL;
310
311 /*
312 * Following commands have data areas so we have to get the location
313 * of the data buffer offset and data buffer length for the particular
314 * command.
315 */
316 switch (shdr->Command) {
317 case SMB2_NEGOTIATE:
318 *off = le16_to_cpu(
319 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
320 *len = le16_to_cpu(
321 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
322 break;
323 case SMB2_SESSION_SETUP:
324 *off = le16_to_cpu(
325 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
326 *len = le16_to_cpu(
327 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
328 break;
329 case SMB2_CREATE:
330 *off = le32_to_cpu(
331 ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
332 *len = le32_to_cpu(
333 ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
334 break;
335 case SMB2_QUERY_INFO:
336 *off = le16_to_cpu(
337 ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
338 *len = le32_to_cpu(
339 ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
340 break;
341 case SMB2_READ:
342 /* TODO: is this a bug ? */
343 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
344 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
345 break;
346 case SMB2_QUERY_DIRECTORY:
347 *off = le16_to_cpu(
348 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
349 *len = le32_to_cpu(
350 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
351 break;
352 case SMB2_IOCTL:
353 *off = le32_to_cpu(
354 ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
355 *len = le32_to_cpu(
356 ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
357 break;
358 case SMB2_CHANGE_NOTIFY:
359 *off = le16_to_cpu(
360 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
361 *len = le32_to_cpu(
362 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
363 break;
364 default:
365 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
366 break;
367 }
368
369 /*
370 * Invalid length or offset probably means data area is invalid, but
371 * we have little choice but to ignore the data area in this case.
372 */
373 if (*off > 4096) {
374 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
375 *len = 0;
376 *off = 0;
377 } else if (*off < 0) {
378 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
379 *off);
380 *off = 0;
381 *len = 0;
382 } else if (*len < 0) {
383 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
384 *len);
385 *len = 0;
386 } else if (*len > 128 * 1024) {
387 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
388 *len = 0;
389 }
390
391 /* return pointer to beginning of data area, ie offset from SMB start */
392 if ((*off != 0) && (*len != 0))
393 return (char *)shdr + *off;
394 else
395 return NULL;
396}
397
398/*
399 * Calculate the size of the SMB message based on the fixed header
400 * portion, the number of word parameters and the data portion of the message.
401 */
402unsigned int
403smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
404{
405 struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)buf;
406 struct smb2_sync_hdr *shdr = &pdu->sync_hdr;
407 int offset; /* the offset from the beginning of SMB to data area */
408 int data_length; /* the length of the variable length data area */
409 /* Structure Size has already been checked to make sure it is 64 */
410 int len = le16_to_cpu(shdr->StructureSize);
411
412 /*
413 * StructureSize2, ie length of fixed parameter area has already
414 * been checked to make sure it is the correct length.
415 */
416 len += le16_to_cpu(pdu->StructureSize2);
417
418 if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
419 goto calc_size_exit;
420
421 smb2_get_data_area_len(&offset, &data_length, shdr);
422 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
423
424 if (data_length > 0) {
425 /*
426 * Check to make sure that data area begins after fixed area,
427 * Note that last byte of the fixed area is part of data area
428 * for some commands, typically those with odd StructureSize,
429 * so we must add one to the calculation.
430 */
431 if (offset + 1 < len) {
432 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
433 offset + 1, len);
434 data_length = 0;
435 } else {
436 len = offset + data_length;
437 }
438 }
439calc_size_exit:
440 cifs_dbg(FYI, "SMB2 len %d\n", len);
441 return len;
442}
443
444/* Note: caller must free return buffer */
445__le16 *
446cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
447{
448 int len;
449 const char *start_of_path;
450 __le16 *to;
451 int map_type;
452
453 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
454 map_type = SFM_MAP_UNI_RSVD;
455 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
456 map_type = SFU_MAP_UNI_RSVD;
457 else
458 map_type = NO_MAP_UNI_RSVD;
459
460 /* Windows doesn't allow paths beginning with \ */
461 if (from[0] == '\\')
462 start_of_path = from + 1;
463
464 /* SMB311 POSIX extensions paths do not include leading slash */
465 else if (cifs_sb_master_tlink(cifs_sb) &&
466 cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
467 (from[0] == '/')) {
468 start_of_path = from + 1;
469 } else
470 start_of_path = from;
471
472 to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
473 cifs_sb->local_nls, map_type);
474 return to;
475}
476
477__le32
478smb2_get_lease_state(struct cifsInodeInfo *cinode)
479{
480 __le32 lease = 0;
481
482 if (CIFS_CACHE_WRITE(cinode))
483 lease |= SMB2_LEASE_WRITE_CACHING;
484 if (CIFS_CACHE_HANDLE(cinode))
485 lease |= SMB2_LEASE_HANDLE_CACHING;
486 if (CIFS_CACHE_READ(cinode))
487 lease |= SMB2_LEASE_READ_CACHING;
488 return lease;
489}
490
491struct smb2_lease_break_work {
492 struct work_struct lease_break;
493 struct tcon_link *tlink;
494 __u8 lease_key[16];
495 __le32 lease_state;
496};
497
498static void
499cifs_ses_oplock_break(struct work_struct *work)
500{
501 struct smb2_lease_break_work *lw = container_of(work,
502 struct smb2_lease_break_work, lease_break);
503 int rc = 0;
504
505 rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
506 lw->lease_state);
507
508 cifs_dbg(FYI, "Lease release rc %d\n", rc);
509 cifs_put_tlink(lw->tlink);
510 kfree(lw);
511}
512
513static void
514smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
515 __le32 new_lease_state)
516{
517 struct smb2_lease_break_work *lw;
518
519 lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
520 if (!lw) {
521 cifs_put_tlink(tlink);
522 return;
523 }
524
525 INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
526 lw->tlink = tlink;
527 lw->lease_state = new_lease_state;
528 memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
529 queue_work(cifsiod_wq, &lw->lease_break);
530}
531
532static bool
533smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
534{
535 __u8 lease_state;
536 struct cifsFileInfo *cfile;
537 struct cifsInodeInfo *cinode;
538 int ack_req = le32_to_cpu(rsp->Flags &
539 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
540
541 lease_state = le32_to_cpu(rsp->NewLeaseState);
542
543 list_for_each_entry(cfile, &tcon->openFileList, 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 TCP_Server_Info *server;
605 struct cifs_ses *ses;
606 struct cifs_tcon *tcon;
607 struct cifs_pending_open *open;
608
609 cifs_dbg(FYI, "Checking for lease break\n");
610
611 /* look up tcon based on tid & uid */
612 spin_lock(&cifs_tcp_ses_lock);
613 list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
614 list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
615 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
616 spin_lock(&tcon->open_file_lock);
617 cifs_stats_inc(
618 &tcon->stats.cifs_stats.num_oplock_brks);
619 if (smb2_tcon_has_lease(tcon, rsp)) {
620 spin_unlock(&tcon->open_file_lock);
621 spin_unlock(&cifs_tcp_ses_lock);
622 return true;
623 }
624 open = smb2_tcon_find_pending_open_lease(tcon,
625 rsp);
626 if (open) {
627 __u8 lease_key[SMB2_LEASE_KEY_SIZE];
628 struct tcon_link *tlink;
629
630 tlink = cifs_get_tlink(open->tlink);
631 memcpy(lease_key, open->lease_key,
632 SMB2_LEASE_KEY_SIZE);
633 spin_unlock(&tcon->open_file_lock);
634 spin_unlock(&cifs_tcp_ses_lock);
635 smb2_queue_pending_open_break(tlink,
636 lease_key,
637 rsp->NewLeaseState);
638 return true;
639 }
640 spin_unlock(&tcon->open_file_lock);
641
642 if (tcon->crfid.is_valid &&
643 !memcmp(rsp->LeaseKey,
644 tcon->crfid.fid->lease_key,
645 SMB2_LEASE_KEY_SIZE)) {
646 tcon->crfid.time = 0;
647 INIT_WORK(&tcon->crfid.lease_break,
648 smb2_cached_lease_break);
649 queue_work(cifsiod_wq,
650 &tcon->crfid.lease_break);
651 spin_unlock(&cifs_tcp_ses_lock);
652 return true;
653 }
654 }
655 }
656 }
657 spin_unlock(&cifs_tcp_ses_lock);
658 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
659 return false;
660}
661
662bool
663smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
664{
665 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
666 struct cifs_ses *ses;
667 struct cifs_tcon *tcon;
668 struct cifsInodeInfo *cinode;
669 struct cifsFileInfo *cfile;
670
671 cifs_dbg(FYI, "Checking for oplock break\n");
672
673 if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
674 return false;
675
676 if (rsp->StructureSize !=
677 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
678 if (le16_to_cpu(rsp->StructureSize) == 44)
679 return smb2_is_valid_lease_break(buffer);
680 else
681 return false;
682 }
683
684 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
685
686 /* look up tcon based on tid & uid */
687 spin_lock(&cifs_tcp_ses_lock);
688 list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
689 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
690
691 spin_lock(&tcon->open_file_lock);
692 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
693 if (rsp->PersistentFid !=
694 cfile->fid.persistent_fid ||
695 rsp->VolatileFid !=
696 cfile->fid.volatile_fid)
697 continue;
698
699 cifs_dbg(FYI, "file id match, oplock break\n");
700 cifs_stats_inc(
701 &tcon->stats.cifs_stats.num_oplock_brks);
702 cinode = CIFS_I(d_inode(cfile->dentry));
703 spin_lock(&cfile->file_info_lock);
704 if (!CIFS_CACHE_WRITE(cinode) &&
705 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
706 cfile->oplock_break_cancelled = true;
707 else
708 cfile->oplock_break_cancelled = false;
709
710 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
711 &cinode->flags);
712
713 cfile->oplock_epoch = 0;
714 cfile->oplock_level = rsp->OplockLevel;
715
716 spin_unlock(&cfile->file_info_lock);
717
718 cifs_queue_oplock_break(cfile);
719
720 spin_unlock(&tcon->open_file_lock);
721 spin_unlock(&cifs_tcp_ses_lock);
722 return true;
723 }
724 spin_unlock(&tcon->open_file_lock);
725 }
726 }
727 spin_unlock(&cifs_tcp_ses_lock);
728 cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
729 return true;
730}
731
732void
733smb2_cancelled_close_fid(struct work_struct *work)
734{
735 struct close_cancelled_open *cancelled = container_of(work,
736 struct close_cancelled_open, work);
737 struct cifs_tcon *tcon = cancelled->tcon;
738 int rc;
739
740 if (cancelled->mid)
741 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
742 cancelled->mid);
743 else
744 cifs_tcon_dbg(VFS, "Close interrupted close\n");
745
746 rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
747 cancelled->fid.volatile_fid);
748 if (rc)
749 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
750
751 cifs_put_tcon(tcon);
752 kfree(cancelled);
753}
754
755/*
756 * Caller should already has an extra reference to @tcon
757 * This function is used to queue work to close a handle to prevent leaks
758 * on the server.
759 * We handle two cases. If an open was interrupted after we sent the
760 * SMB2_CREATE to the server but before we processed the reply, and second
761 * if a close was interrupted before we sent the SMB2_CLOSE to the server.
762 */
763static int
764__smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
765 __u64 persistent_fid, __u64 volatile_fid)
766{
767 struct close_cancelled_open *cancelled;
768
769 cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
770 if (!cancelled)
771 return -ENOMEM;
772
773 cancelled->fid.persistent_fid = persistent_fid;
774 cancelled->fid.volatile_fid = volatile_fid;
775 cancelled->tcon = tcon;
776 cancelled->cmd = cmd;
777 cancelled->mid = mid;
778 INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
779 WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
780
781 return 0;
782}
783
784int
785smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
786 __u64 volatile_fid)
787{
788 int rc;
789
790 cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
791 spin_lock(&cifs_tcp_ses_lock);
792 if (tcon->tc_count <= 0) {
793 struct TCP_Server_Info *server = NULL;
794
795 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
796 spin_unlock(&cifs_tcp_ses_lock);
797
798 if (tcon->ses)
799 server = tcon->ses->server;
800
801 cifs_server_dbg(FYI, "tid=%u: tcon is closing, skipping async close retry of fid %llu %llu\n",
802 tcon->tid, persistent_fid, volatile_fid);
803
804 return 0;
805 }
806 tcon->tc_count++;
807 spin_unlock(&cifs_tcp_ses_lock);
808
809 rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
810 persistent_fid, volatile_fid);
811 if (rc)
812 cifs_put_tcon(tcon);
813
814 return rc;
815}
816
817int
818smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
819{
820 struct smb2_sync_hdr *sync_hdr = mid->resp_buf;
821 struct smb2_create_rsp *rsp = mid->resp_buf;
822 struct cifs_tcon *tcon;
823 int rc;
824
825 if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || sync_hdr->Command != SMB2_CREATE ||
826 sync_hdr->Status != STATUS_SUCCESS)
827 return 0;
828
829 tcon = smb2_find_smb_tcon(server, sync_hdr->SessionId,
830 sync_hdr->TreeId);
831 if (!tcon)
832 return -ENOENT;
833
834 rc = __smb2_handle_cancelled_cmd(tcon,
835 le16_to_cpu(sync_hdr->Command),
836 le64_to_cpu(sync_hdr->MessageId),
837 rsp->PersistentFileId,
838 rsp->VolatileFileId);
839 if (rc)
840 cifs_put_tcon(tcon);
841
842 return rc;
843}
844
845/**
846 * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
847 *
848 * Assumes @iov does not contain the rfc1002 length and iov[0] has the
849 * SMB2 header.
850 *
851 * @ses: server session structure
852 * @iov: array containing the SMB request we will send to the server
853 * @nvec: number of array entries for the iov
854 */
855int
856smb311_update_preauth_hash(struct cifs_ses *ses, struct kvec *iov, int nvec)
857{
858 int i, rc;
859 struct sdesc *d;
860 struct smb2_sync_hdr *hdr;
861 struct TCP_Server_Info *server = cifs_ses_server(ses);
862
863 hdr = (struct smb2_sync_hdr *)iov[0].iov_base;
864 /* neg prot are always taken */
865 if (hdr->Command == SMB2_NEGOTIATE)
866 goto ok;
867
868 /*
869 * If we process a command which wasn't a negprot it means the
870 * neg prot was already done, so the server dialect was set
871 * and we can test it. Preauth requires 3.1.1 for now.
872 */
873 if (server->dialect != SMB311_PROT_ID)
874 return 0;
875
876 if (hdr->Command != SMB2_SESSION_SETUP)
877 return 0;
878
879 /* skip last sess setup response */
880 if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
881 && (hdr->Status == NT_STATUS_OK
882 || (hdr->Status !=
883 cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
884 return 0;
885
886ok:
887 rc = smb311_crypto_shash_allocate(server);
888 if (rc)
889 return rc;
890
891 d = server->secmech.sdescsha512;
892 rc = crypto_shash_init(&d->shash);
893 if (rc) {
894 cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
895 return rc;
896 }
897
898 rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
899 SMB2_PREAUTH_HASH_SIZE);
900 if (rc) {
901 cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
902 return rc;
903 }
904
905 for (i = 0; i < nvec; i++) {
906 rc = crypto_shash_update(&d->shash,
907 iov[i].iov_base, iov[i].iov_len);
908 if (rc) {
909 cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
910 __func__);
911 return rc;
912 }
913 }
914
915 rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
916 if (rc) {
917 cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
918 __func__);
919 return rc;
920 }
921
922 return 0;
923}