-
Notifications
You must be signed in to change notification settings - Fork 102
/
smb2pdu.c
5622 lines (4848 loc) · 156 KB
/
smb2pdu.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// SPDX-License-Identifier: LGPL-2.1
/*
*
* Copyright (C) International Business Machines Corp., 2009, 2013
* Etersoft, 2012
* Author(s): Steve French (sfrench@us.ibm.com)
* Pavel Shilovsky (pshilovsky@samba.org) 2012
*
* Contains the routines for constructing the SMB2 PDUs themselves
*
*/
/* SMB2 PDU handling routines here - except for leftovers (eg session setup) */
/* Note that there are handle based routines which must be */
/* treated slightly differently for reconnection purposes since we never */
/* want to reuse a stale file handle and only the caller knows the file info */
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/vfs.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/uaccess.h>
#include <linux/uuid.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include "cifsglob.h"
#include "cifsacl.h"
#include "cifsproto.h"
#include "smb2proto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "ntlmssp.h"
#include "smb2status.h"
#include "smb2glob.h"
#include "cifspdu.h"
#include "cifs_spnego.h"
#include "smbdirect.h"
#include "trace.h"
#ifdef CONFIG_CIFS_DFS_UPCALL
#include "dfs_cache.h"
#endif
/*
* The following table defines the expected "StructureSize" of SMB2 requests
* in order by SMB2 command. This is similar to "wct" in SMB/CIFS requests.
*
* Note that commands are defined in smb2pdu.h in le16 but the array below is
* indexed by command in host byte order.
*/
static const int smb2_req_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
/* SMB2_NEGOTIATE */ 36,
/* SMB2_SESSION_SETUP */ 25,
/* SMB2_LOGOFF */ 4,
/* SMB2_TREE_CONNECT */ 9,
/* SMB2_TREE_DISCONNECT */ 4,
/* SMB2_CREATE */ 57,
/* SMB2_CLOSE */ 24,
/* SMB2_FLUSH */ 24,
/* SMB2_READ */ 49,
/* SMB2_WRITE */ 49,
/* SMB2_LOCK */ 48,
/* SMB2_IOCTL */ 57,
/* SMB2_CANCEL */ 4,
/* SMB2_ECHO */ 4,
/* SMB2_QUERY_DIRECTORY */ 33,
/* SMB2_CHANGE_NOTIFY */ 32,
/* SMB2_QUERY_INFO */ 41,
/* SMB2_SET_INFO */ 33,
/* SMB2_OPLOCK_BREAK */ 24 /* BB this is 36 for LEASE_BREAK variant */
};
int smb3_encryption_required(const struct cifs_tcon *tcon)
{
if (!tcon || !tcon->ses)
return 0;
if ((tcon->ses->session_flags & SMB2_SESSION_FLAG_ENCRYPT_DATA) ||
(tcon->share_flags & SHI1005_FLAGS_ENCRYPT_DATA))
return 1;
if (tcon->seal &&
(tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION))
return 1;
return 0;
}
static void
smb2_hdr_assemble(struct smb2_hdr *shdr, __le16 smb2_cmd,
const struct cifs_tcon *tcon,
struct TCP_Server_Info *server)
{
shdr->ProtocolId = SMB2_PROTO_NUMBER;
shdr->StructureSize = cpu_to_le16(64);
shdr->Command = smb2_cmd;
if (server) {
spin_lock(&server->req_lock);
/* Request up to 10 credits but don't go over the limit. */
if (server->credits >= server->max_credits)
shdr->CreditRequest = cpu_to_le16(0);
else
shdr->CreditRequest = cpu_to_le16(
min_t(int, server->max_credits -
server->credits, 10));
spin_unlock(&server->req_lock);
} else {
shdr->CreditRequest = cpu_to_le16(2);
}
shdr->Id.SyncId.ProcessId = cpu_to_le32((__u16)current->tgid);
if (!tcon)
goto out;
/* GLOBAL_CAP_LARGE_MTU will only be set if dialect > SMB2.02 */
/* See sections 2.2.4 and 3.2.4.1.5 of MS-SMB2 */
if (server && (server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
shdr->CreditCharge = cpu_to_le16(1);
/* else CreditCharge MBZ */
shdr->Id.SyncId.TreeId = cpu_to_le32(tcon->tid);
/* Uid is not converted */
if (tcon->ses)
shdr->SessionId = cpu_to_le64(tcon->ses->Suid);
/*
* If we would set SMB2_FLAGS_DFS_OPERATIONS on open we also would have
* to pass the path on the Open SMB prefixed by \\server\share.
* Not sure when we would need to do the augmented path (if ever) and
* setting this flag breaks the SMB2 open operation since it is
* illegal to send an empty path name (without \\server\share prefix)
* when the DFS flag is set in the SMB open header. We could
* consider setting the flag on all operations other than open
* but it is safer to net set it for now.
*/
/* if (tcon->share_flags & SHI1005_FLAGS_DFS)
shdr->Flags |= SMB2_FLAGS_DFS_OPERATIONS; */
if (server && server->sign && !smb3_encryption_required(tcon))
shdr->Flags |= SMB2_FLAGS_SIGNED;
out:
return;
}
static int
smb2_reconnect(__le16 smb2_command, struct cifs_tcon *tcon,
struct TCP_Server_Info *server)
{
int rc = 0;
struct nls_table *nls_codepage;
struct cifs_ses *ses;
int retries;
/*
* SMB2s NegProt, SessSetup, Logoff do not have tcon yet so
* check for tcp and smb session status done differently
* for those three - in the calling routine.
*/
if (tcon == NULL)
return 0;
/*
* Need to also skip SMB2_IOCTL because it is used for checking nested dfs links in
* cifs_tree_connect().
*/
if (smb2_command == SMB2_TREE_CONNECT || smb2_command == SMB2_IOCTL)
return 0;
spin_lock(&cifs_tcp_ses_lock);
if (tcon->status == TID_EXITING) {
/*
* only tree disconnect, open, and write,
* (and ulogoff which does not have tcon)
* are allowed as we start force umount.
*/
if ((smb2_command != SMB2_WRITE) &&
(smb2_command != SMB2_CREATE) &&
(smb2_command != SMB2_TREE_DISCONNECT)) {
spin_unlock(&cifs_tcp_ses_lock);
cifs_dbg(FYI, "can not send cmd %d while umounting\n",
smb2_command);
return -ENODEV;
}
}
spin_unlock(&cifs_tcp_ses_lock);
if ((!tcon->ses) || (tcon->ses->status == CifsExiting) ||
(!tcon->ses->server) || !server)
return -EIO;
ses = tcon->ses;
retries = server->nr_targets;
/*
* Give demultiplex thread up to 10 seconds to each target available for
* reconnect -- should be greater than cifs socket timeout which is 7
* seconds.
*/
while (server->tcpStatus == CifsNeedReconnect) {
/*
* Return to caller for TREE_DISCONNECT and LOGOFF and CLOSE
* here since they are implicitly done when session drops.
*/
switch (smb2_command) {
/*
* BB Should we keep oplock break and add flush to exceptions?
*/
case SMB2_TREE_DISCONNECT:
case SMB2_CANCEL:
case SMB2_CLOSE:
case SMB2_OPLOCK_BREAK:
return -EAGAIN;
}
rc = wait_event_interruptible_timeout(server->response_q,
(server->tcpStatus != CifsNeedReconnect),
10 * HZ);
if (rc < 0) {
cifs_dbg(FYI, "%s: aborting reconnect due to a received signal by the process\n",
__func__);
return -ERESTARTSYS;
}
/* are we still trying to reconnect? */
spin_lock(&cifs_tcp_ses_lock);
if (server->tcpStatus != CifsNeedReconnect) {
spin_unlock(&cifs_tcp_ses_lock);
break;
}
spin_unlock(&cifs_tcp_ses_lock);
if (retries && --retries)
continue;
/*
* on "soft" mounts we wait once. Hard mounts keep
* retrying until process is killed or server comes
* back on-line
*/
if (!tcon->retry) {
cifs_dbg(FYI, "gave up waiting on reconnect in smb_init\n");
return -EHOSTDOWN;
}
retries = server->nr_targets;
}
spin_lock(&ses->chan_lock);
if (!cifs_chan_needs_reconnect(ses, server) && !tcon->need_reconnect) {
spin_unlock(&ses->chan_lock);
return 0;
}
spin_unlock(&ses->chan_lock);
cifs_dbg(FYI, "sess reconnect mask: 0x%lx, tcon reconnect: %d",
tcon->ses->chans_need_reconnect,
tcon->need_reconnect);
nls_codepage = load_nls_default();
/*
* Recheck after acquire mutex. If another thread is negotiating
* and the server never sends an answer the socket will be closed
* and tcpStatus set to reconnect.
*/
spin_lock(&cifs_tcp_ses_lock);
if (server->tcpStatus == CifsNeedReconnect) {
spin_unlock(&cifs_tcp_ses_lock);
rc = -EHOSTDOWN;
goto out;
}
spin_unlock(&cifs_tcp_ses_lock);
/*
* need to prevent multiple threads trying to simultaneously
* reconnect the same SMB session
*/
spin_lock(&ses->chan_lock);
if (!cifs_chan_needs_reconnect(ses, server)) {
spin_unlock(&ses->chan_lock);
/* this means that we only need to tree connect */
if (tcon->need_reconnect)
goto skip_sess_setup;
goto out;
}
spin_unlock(&ses->chan_lock);
mutex_lock(&ses->session_mutex);
rc = cifs_negotiate_protocol(0, ses, server);
if (!rc) {
rc = cifs_setup_session(0, ses, server, nls_codepage);
if ((rc == -EACCES) && !tcon->retry) {
mutex_unlock(&ses->session_mutex);
rc = -EHOSTDOWN;
goto failed;
} else if (rc) {
mutex_unlock(&ses->session_mutex);
goto out;
}
} else {
mutex_unlock(&ses->session_mutex);
goto out;
}
mutex_unlock(&ses->session_mutex);
skip_sess_setup:
mutex_lock(&ses->session_mutex);
if (!tcon->need_reconnect) {
mutex_unlock(&ses->session_mutex);
goto out;
}
cifs_mark_open_files_invalid(tcon);
if (tcon->use_persistent)
tcon->need_reopen_files = true;
rc = cifs_tree_connect(0, tcon, nls_codepage);
mutex_unlock(&ses->session_mutex);
cifs_dbg(FYI, "reconnect tcon rc = %d\n", rc);
if (rc) {
/* If sess reconnected but tcon didn't, something strange ... */
pr_warn_once("reconnect tcon failed rc = %d\n", rc);
goto out;
}
if (smb2_command != SMB2_INTERNAL_CMD)
mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
atomic_inc(&tconInfoReconnectCount);
out:
/*
* Check if handle based operation so we know whether we can continue
* or not without returning to caller to reset file handle.
*/
/*
* BB Is flush done by server on drop of tcp session? Should we special
* case it and skip above?
*/
switch (smb2_command) {
case SMB2_FLUSH:
case SMB2_READ:
case SMB2_WRITE:
case SMB2_LOCK:
case SMB2_IOCTL:
case SMB2_QUERY_DIRECTORY:
case SMB2_CHANGE_NOTIFY:
case SMB2_QUERY_INFO:
case SMB2_SET_INFO:
rc = -EAGAIN;
}
failed:
unload_nls(nls_codepage);
return rc;
}
static void
fill_small_buf(__le16 smb2_command, struct cifs_tcon *tcon,
struct TCP_Server_Info *server,
void *buf,
unsigned int *total_len)
{
struct smb2_pdu *spdu = (struct smb2_pdu *)buf;
/* lookup word count ie StructureSize from table */
__u16 parmsize = smb2_req_struct_sizes[le16_to_cpu(smb2_command)];
/*
* smaller than SMALL_BUFFER_SIZE but bigger than fixed area of
* largest operations (Create)
*/
memset(buf, 0, 256);
smb2_hdr_assemble(&spdu->hdr, smb2_command, tcon, server);
spdu->StructureSize2 = cpu_to_le16(parmsize);
*total_len = parmsize + sizeof(struct smb2_hdr);
}
/*
* Allocate and return pointer to an SMB request hdr, and set basic
* SMB information in the SMB header. If the return code is zero, this
* function must have filled in request_buf pointer.
*/
static int __smb2_plain_req_init(__le16 smb2_command, struct cifs_tcon *tcon,
struct TCP_Server_Info *server,
void **request_buf, unsigned int *total_len)
{
/* BB eventually switch this to SMB2 specific small buf size */
if (smb2_command == SMB2_SET_INFO)
*request_buf = cifs_buf_get();
else
*request_buf = cifs_small_buf_get();
if (*request_buf == NULL) {
/* BB should we add a retry in here if not a writepage? */
return -ENOMEM;
}
fill_small_buf(smb2_command, tcon, server,
(struct smb2_hdr *)(*request_buf),
total_len);
if (tcon != NULL) {
uint16_t com_code = le16_to_cpu(smb2_command);
cifs_stats_inc(&tcon->stats.smb2_stats.smb2_com_sent[com_code]);
cifs_stats_inc(&tcon->num_smbs_sent);
}
return 0;
}
static int smb2_plain_req_init(__le16 smb2_command, struct cifs_tcon *tcon,
struct TCP_Server_Info *server,
void **request_buf, unsigned int *total_len)
{
int rc;
rc = smb2_reconnect(smb2_command, tcon, server);
if (rc)
return rc;
return __smb2_plain_req_init(smb2_command, tcon, server, request_buf,
total_len);
}
static int smb2_ioctl_req_init(u32 opcode, struct cifs_tcon *tcon,
struct TCP_Server_Info *server,
void **request_buf, unsigned int *total_len)
{
/* Skip reconnect only for FSCTL_VALIDATE_NEGOTIATE_INFO IOCTLs */
if (opcode == FSCTL_VALIDATE_NEGOTIATE_INFO) {
return __smb2_plain_req_init(SMB2_IOCTL, tcon, server,
request_buf, total_len);
}
return smb2_plain_req_init(SMB2_IOCTL, tcon, server,
request_buf, total_len);
}
/* For explanation of negotiate contexts see MS-SMB2 section 2.2.3.1 */
static void
build_preauth_ctxt(struct smb2_preauth_neg_context *pneg_ctxt)
{
pneg_ctxt->ContextType = SMB2_PREAUTH_INTEGRITY_CAPABILITIES;
pneg_ctxt->DataLength = cpu_to_le16(38);
pneg_ctxt->HashAlgorithmCount = cpu_to_le16(1);
pneg_ctxt->SaltLength = cpu_to_le16(SMB311_SALT_SIZE);
get_random_bytes(pneg_ctxt->Salt, SMB311_SALT_SIZE);
pneg_ctxt->HashAlgorithms = SMB2_PREAUTH_INTEGRITY_SHA512;
}
static void
build_compression_ctxt(struct smb2_compression_capabilities_context *pneg_ctxt)
{
pneg_ctxt->ContextType = SMB2_COMPRESSION_CAPABILITIES;
pneg_ctxt->DataLength =
cpu_to_le16(sizeof(struct smb2_compression_capabilities_context)
- sizeof(struct smb2_neg_context));
pneg_ctxt->CompressionAlgorithmCount = cpu_to_le16(3);
pneg_ctxt->CompressionAlgorithms[0] = SMB3_COMPRESS_LZ77;
pneg_ctxt->CompressionAlgorithms[1] = SMB3_COMPRESS_LZ77_HUFF;
pneg_ctxt->CompressionAlgorithms[2] = SMB3_COMPRESS_LZNT1;
}
static unsigned int
build_signing_ctxt(struct smb2_signing_capabilities *pneg_ctxt)
{
unsigned int ctxt_len = sizeof(struct smb2_signing_capabilities);
unsigned short num_algs = 1; /* number of signing algorithms sent */
pneg_ctxt->ContextType = SMB2_SIGNING_CAPABILITIES;
/*
* Context Data length must be rounded to multiple of 8 for some servers
*/
pneg_ctxt->DataLength = cpu_to_le16(DIV_ROUND_UP(
sizeof(struct smb2_signing_capabilities) -
sizeof(struct smb2_neg_context) +
(num_algs * 2 /* sizeof u16 */), 8) * 8);
pneg_ctxt->SigningAlgorithmCount = cpu_to_le16(num_algs);
pneg_ctxt->SigningAlgorithms[0] = cpu_to_le16(SIGNING_ALG_AES_CMAC);
ctxt_len += 2 /* sizeof le16 */ * num_algs;
ctxt_len = DIV_ROUND_UP(ctxt_len, 8) * 8;
return ctxt_len;
/* TBD add SIGNING_ALG_AES_GMAC and/or SIGNING_ALG_HMAC_SHA256 */
}
static void
build_encrypt_ctxt(struct smb2_encryption_neg_context *pneg_ctxt)
{
pneg_ctxt->ContextType = SMB2_ENCRYPTION_CAPABILITIES;
if (require_gcm_256) {
pneg_ctxt->DataLength = cpu_to_le16(4); /* Cipher Count + 1 cipher */
pneg_ctxt->CipherCount = cpu_to_le16(1);
pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES256_GCM;
} else if (enable_gcm_256) {
pneg_ctxt->DataLength = cpu_to_le16(8); /* Cipher Count + 3 ciphers */
pneg_ctxt->CipherCount = cpu_to_le16(3);
pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES128_GCM;
pneg_ctxt->Ciphers[1] = SMB2_ENCRYPTION_AES256_GCM;
pneg_ctxt->Ciphers[2] = SMB2_ENCRYPTION_AES128_CCM;
} else {
pneg_ctxt->DataLength = cpu_to_le16(6); /* Cipher Count + 2 ciphers */
pneg_ctxt->CipherCount = cpu_to_le16(2);
pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES128_GCM;
pneg_ctxt->Ciphers[1] = SMB2_ENCRYPTION_AES128_CCM;
}
}
static unsigned int
build_netname_ctxt(struct smb2_netname_neg_context *pneg_ctxt, char *hostname)
{
struct nls_table *cp = load_nls_default();
pneg_ctxt->ContextType = SMB2_NETNAME_NEGOTIATE_CONTEXT_ID;
/* copy up to max of first 100 bytes of server name to NetName field */
pneg_ctxt->DataLength = cpu_to_le16(2 * cifs_strtoUTF16(pneg_ctxt->NetName, hostname, 100, cp));
/* context size is DataLength + minimal smb2_neg_context */
return DIV_ROUND_UP(le16_to_cpu(pneg_ctxt->DataLength) +
sizeof(struct smb2_neg_context), 8) * 8;
}
static void
build_posix_ctxt(struct smb2_posix_neg_context *pneg_ctxt)
{
pneg_ctxt->ContextType = SMB2_POSIX_EXTENSIONS_AVAILABLE;
pneg_ctxt->DataLength = cpu_to_le16(POSIX_CTXT_DATA_LEN);
/* SMB2_CREATE_TAG_POSIX is "0x93AD25509CB411E7B42383DE968BCD7C" */
pneg_ctxt->Name[0] = 0x93;
pneg_ctxt->Name[1] = 0xAD;
pneg_ctxt->Name[2] = 0x25;
pneg_ctxt->Name[3] = 0x50;
pneg_ctxt->Name[4] = 0x9C;
pneg_ctxt->Name[5] = 0xB4;
pneg_ctxt->Name[6] = 0x11;
pneg_ctxt->Name[7] = 0xE7;
pneg_ctxt->Name[8] = 0xB4;
pneg_ctxt->Name[9] = 0x23;
pneg_ctxt->Name[10] = 0x83;
pneg_ctxt->Name[11] = 0xDE;
pneg_ctxt->Name[12] = 0x96;
pneg_ctxt->Name[13] = 0x8B;
pneg_ctxt->Name[14] = 0xCD;
pneg_ctxt->Name[15] = 0x7C;
}
static void
assemble_neg_contexts(struct smb2_negotiate_req *req,
struct TCP_Server_Info *server, unsigned int *total_len)
{
char *pneg_ctxt;
unsigned int ctxt_len, neg_context_count;
if (*total_len > 200) {
/* In case length corrupted don't want to overrun smb buffer */
cifs_server_dbg(VFS, "Bad frame length assembling neg contexts\n");
return;
}
/*
* round up total_len of fixed part of SMB3 negotiate request to 8
* byte boundary before adding negotiate contexts
*/
*total_len = roundup(*total_len, 8);
pneg_ctxt = (*total_len) + (char *)req;
req->NegotiateContextOffset = cpu_to_le32(*total_len);
build_preauth_ctxt((struct smb2_preauth_neg_context *)pneg_ctxt);
ctxt_len = DIV_ROUND_UP(sizeof(struct smb2_preauth_neg_context), 8) * 8;
*total_len += ctxt_len;
pneg_ctxt += ctxt_len;
build_encrypt_ctxt((struct smb2_encryption_neg_context *)pneg_ctxt);
ctxt_len = DIV_ROUND_UP(sizeof(struct smb2_encryption_neg_context), 8) * 8;
*total_len += ctxt_len;
pneg_ctxt += ctxt_len;
build_posix_ctxt((struct smb2_posix_neg_context *)pneg_ctxt);
*total_len += sizeof(struct smb2_posix_neg_context);
pneg_ctxt += sizeof(struct smb2_posix_neg_context);
if (server->hostname && (server->hostname[0] != 0)) {
ctxt_len = build_netname_ctxt((struct smb2_netname_neg_context *)pneg_ctxt,
server->hostname);
*total_len += ctxt_len;
pneg_ctxt += ctxt_len;
neg_context_count = 4;
} else /* second channels do not have a hostname */
neg_context_count = 3;
if (server->compress_algorithm) {
build_compression_ctxt((struct smb2_compression_capabilities_context *)
pneg_ctxt);
ctxt_len = DIV_ROUND_UP(
sizeof(struct smb2_compression_capabilities_context),
8) * 8;
*total_len += ctxt_len;
pneg_ctxt += ctxt_len;
neg_context_count++;
}
if (enable_negotiate_signing) {
ctxt_len = build_signing_ctxt((struct smb2_signing_capabilities *)
pneg_ctxt);
*total_len += ctxt_len;
pneg_ctxt += ctxt_len;
neg_context_count++;
}
/* check for and add transport_capabilities and signing capabilities */
req->NegotiateContextCount = cpu_to_le16(neg_context_count);
}
static void decode_preauth_context(struct smb2_preauth_neg_context *ctxt)
{
unsigned int len = le16_to_cpu(ctxt->DataLength);
/* If invalid preauth context warn but use what we requested, SHA-512 */
if (len < MIN_PREAUTH_CTXT_DATA_LEN) {
pr_warn_once("server sent bad preauth context\n");
return;
} else if (len < MIN_PREAUTH_CTXT_DATA_LEN + le16_to_cpu(ctxt->SaltLength)) {
pr_warn_once("server sent invalid SaltLength\n");
return;
}
if (le16_to_cpu(ctxt->HashAlgorithmCount) != 1)
pr_warn_once("Invalid SMB3 hash algorithm count\n");
if (ctxt->HashAlgorithms != SMB2_PREAUTH_INTEGRITY_SHA512)
pr_warn_once("unknown SMB3 hash algorithm\n");
}
static void decode_compress_ctx(struct TCP_Server_Info *server,
struct smb2_compression_capabilities_context *ctxt)
{
unsigned int len = le16_to_cpu(ctxt->DataLength);
/* sizeof compress context is a one element compression capbility struct */
if (len < 10) {
pr_warn_once("server sent bad compression cntxt\n");
return;
}
if (le16_to_cpu(ctxt->CompressionAlgorithmCount) != 1) {
pr_warn_once("Invalid SMB3 compress algorithm count\n");
return;
}
if (le16_to_cpu(ctxt->CompressionAlgorithms[0]) > 3) {
pr_warn_once("unknown compression algorithm\n");
return;
}
server->compress_algorithm = ctxt->CompressionAlgorithms[0];
}
static int decode_encrypt_ctx(struct TCP_Server_Info *server,
struct smb2_encryption_neg_context *ctxt)
{
unsigned int len = le16_to_cpu(ctxt->DataLength);
cifs_dbg(FYI, "decode SMB3.11 encryption neg context of len %d\n", len);
if (len < MIN_ENCRYPT_CTXT_DATA_LEN) {
pr_warn_once("server sent bad crypto ctxt len\n");
return -EINVAL;
}
if (le16_to_cpu(ctxt->CipherCount) != 1) {
pr_warn_once("Invalid SMB3.11 cipher count\n");
return -EINVAL;
}
cifs_dbg(FYI, "SMB311 cipher type:%d\n", le16_to_cpu(ctxt->Ciphers[0]));
if (require_gcm_256) {
if (ctxt->Ciphers[0] != SMB2_ENCRYPTION_AES256_GCM) {
cifs_dbg(VFS, "Server does not support requested encryption type (AES256 GCM)\n");
return -EOPNOTSUPP;
}
} else if (ctxt->Ciphers[0] == 0) {
/*
* e.g. if server only supported AES256_CCM (very unlikely)
* or server supported no encryption types or had all disabled.
* Since GLOBAL_CAP_ENCRYPTION will be not set, in the case
* in which mount requested encryption ("seal") checks later
* on during tree connection will return proper rc, but if
* seal not requested by client, since server is allowed to
* return 0 to indicate no supported cipher, we can't fail here
*/
server->cipher_type = 0;
server->capabilities &= ~SMB2_GLOBAL_CAP_ENCRYPTION;
pr_warn_once("Server does not support requested encryption types\n");
return 0;
} else if ((ctxt->Ciphers[0] != SMB2_ENCRYPTION_AES128_CCM) &&
(ctxt->Ciphers[0] != SMB2_ENCRYPTION_AES128_GCM) &&
(ctxt->Ciphers[0] != SMB2_ENCRYPTION_AES256_GCM)) {
/* server returned a cipher we didn't ask for */
pr_warn_once("Invalid SMB3.11 cipher returned\n");
return -EINVAL;
}
server->cipher_type = ctxt->Ciphers[0];
server->capabilities |= SMB2_GLOBAL_CAP_ENCRYPTION;
return 0;
}
static void decode_signing_ctx(struct TCP_Server_Info *server,
struct smb2_signing_capabilities *pctxt)
{
unsigned int len = le16_to_cpu(pctxt->DataLength);
if ((len < 4) || (len > 16)) {
pr_warn_once("server sent bad signing negcontext\n");
return;
}
if (le16_to_cpu(pctxt->SigningAlgorithmCount) != 1) {
pr_warn_once("Invalid signing algorithm count\n");
return;
}
if (le16_to_cpu(pctxt->SigningAlgorithms[0]) > 2) {
pr_warn_once("unknown signing algorithm\n");
return;
}
server->signing_negotiated = true;
server->signing_algorithm = le16_to_cpu(pctxt->SigningAlgorithms[0]);
cifs_dbg(FYI, "signing algorithm %d chosen\n",
server->signing_algorithm);
}
static int smb311_decode_neg_context(struct smb2_negotiate_rsp *rsp,
struct TCP_Server_Info *server,
unsigned int len_of_smb)
{
struct smb2_neg_context *pctx;
unsigned int offset = le32_to_cpu(rsp->NegotiateContextOffset);
unsigned int ctxt_cnt = le16_to_cpu(rsp->NegotiateContextCount);
unsigned int len_of_ctxts, i;
int rc = 0;
cifs_dbg(FYI, "decoding %d negotiate contexts\n", ctxt_cnt);
if (len_of_smb <= offset) {
cifs_server_dbg(VFS, "Invalid response: negotiate context offset\n");
return -EINVAL;
}
len_of_ctxts = len_of_smb - offset;
for (i = 0; i < ctxt_cnt; i++) {
int clen;
/* check that offset is not beyond end of SMB */
if (len_of_ctxts == 0)
break;
if (len_of_ctxts < sizeof(struct smb2_neg_context))
break;
pctx = (struct smb2_neg_context *)(offset + (char *)rsp);
clen = le16_to_cpu(pctx->DataLength);
if (clen > len_of_ctxts)
break;
if (pctx->ContextType == SMB2_PREAUTH_INTEGRITY_CAPABILITIES)
decode_preauth_context(
(struct smb2_preauth_neg_context *)pctx);
else if (pctx->ContextType == SMB2_ENCRYPTION_CAPABILITIES)
rc = decode_encrypt_ctx(server,
(struct smb2_encryption_neg_context *)pctx);
else if (pctx->ContextType == SMB2_COMPRESSION_CAPABILITIES)
decode_compress_ctx(server,
(struct smb2_compression_capabilities_context *)pctx);
else if (pctx->ContextType == SMB2_POSIX_EXTENSIONS_AVAILABLE)
server->posix_ext_supported = true;
else if (pctx->ContextType == SMB2_SIGNING_CAPABILITIES)
decode_signing_ctx(server,
(struct smb2_signing_capabilities *)pctx);
else
cifs_server_dbg(VFS, "unknown negcontext of type %d ignored\n",
le16_to_cpu(pctx->ContextType));
if (rc)
break;
/* offsets must be 8 byte aligned */
clen = (clen + 7) & ~0x7;
offset += clen + sizeof(struct smb2_neg_context);
len_of_ctxts -= clen;
}
return rc;
}
static struct create_posix *
create_posix_buf(umode_t mode)
{
struct create_posix *buf;
buf = kzalloc(sizeof(struct create_posix),
GFP_KERNEL);
if (!buf)
return NULL;
buf->ccontext.DataOffset =
cpu_to_le16(offsetof(struct create_posix, Mode));
buf->ccontext.DataLength = cpu_to_le32(4);
buf->ccontext.NameOffset =
cpu_to_le16(offsetof(struct create_posix, Name));
buf->ccontext.NameLength = cpu_to_le16(16);
/* SMB2_CREATE_TAG_POSIX is "0x93AD25509CB411E7B42383DE968BCD7C" */
buf->Name[0] = 0x93;
buf->Name[1] = 0xAD;
buf->Name[2] = 0x25;
buf->Name[3] = 0x50;
buf->Name[4] = 0x9C;
buf->Name[5] = 0xB4;
buf->Name[6] = 0x11;
buf->Name[7] = 0xE7;
buf->Name[8] = 0xB4;
buf->Name[9] = 0x23;
buf->Name[10] = 0x83;
buf->Name[11] = 0xDE;
buf->Name[12] = 0x96;
buf->Name[13] = 0x8B;
buf->Name[14] = 0xCD;
buf->Name[15] = 0x7C;
buf->Mode = cpu_to_le32(mode);
cifs_dbg(FYI, "mode on posix create 0%o\n", mode);
return buf;
}
static int
add_posix_context(struct kvec *iov, unsigned int *num_iovec, umode_t mode)
{
struct smb2_create_req *req = iov[0].iov_base;
unsigned int num = *num_iovec;
iov[num].iov_base = create_posix_buf(mode);
if (mode == ACL_NO_MODE)
cifs_dbg(FYI, "Invalid mode\n");
if (iov[num].iov_base == NULL)
return -ENOMEM;
iov[num].iov_len = sizeof(struct create_posix);
if (!req->CreateContextsOffset)
req->CreateContextsOffset = cpu_to_le32(
sizeof(struct smb2_create_req) +
iov[num - 1].iov_len);
le32_add_cpu(&req->CreateContextsLength, sizeof(struct create_posix));
*num_iovec = num + 1;
return 0;
}
/*
*
* SMB2 Worker functions follow:
*
* The general structure of the worker functions is:
* 1) Call smb2_init (assembles SMB2 header)
* 2) Initialize SMB2 command specific fields in fixed length area of SMB
* 3) Call smb_sendrcv2 (sends request on socket and waits for response)
* 4) Decode SMB2 command specific fields in the fixed length area
* 5) Decode variable length data area (if any for this SMB2 command type)
* 6) Call free smb buffer
* 7) return
*
*/
int
SMB2_negotiate(const unsigned int xid,
struct cifs_ses *ses,
struct TCP_Server_Info *server)
{
struct smb_rqst rqst;
struct smb2_negotiate_req *req;
struct smb2_negotiate_rsp *rsp;
struct kvec iov[1];
struct kvec rsp_iov;
int rc = 0;
int resp_buftype;
int blob_offset, blob_length;
char *security_blob;
int flags = CIFS_NEG_OP;
unsigned int total_len;
cifs_dbg(FYI, "Negotiate protocol\n");
if (!server) {
WARN(1, "%s: server is NULL!\n", __func__);
return -EIO;
}
rc = smb2_plain_req_init(SMB2_NEGOTIATE, NULL, server,
(void **) &req, &total_len);
if (rc)
return rc;
req->hdr.SessionId = 0;
memset(server->preauth_sha_hash, 0, SMB2_PREAUTH_HASH_SIZE);
memset(ses->preauth_sha_hash, 0, SMB2_PREAUTH_HASH_SIZE);
if (strcmp(server->vals->version_string,
SMB3ANY_VERSION_STRING) == 0) {
req->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
req->Dialects[2] = cpu_to_le16(SMB311_PROT_ID);
req->DialectCount = cpu_to_le16(3);
total_len += 6;
} else if (strcmp(server->vals->version_string,
SMBDEFAULT_VERSION_STRING) == 0) {
req->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
req->Dialects[1] = cpu_to_le16(SMB30_PROT_ID);
req->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
req->Dialects[3] = cpu_to_le16(SMB311_PROT_ID);
req->DialectCount = cpu_to_le16(4);
total_len += 8;
} else {
/* otherwise send specific dialect */
req->Dialects[0] = cpu_to_le16(server->vals->protocol_id);
req->DialectCount = cpu_to_le16(1);
total_len += 2;
}
/* only one of SMB2 signing flags may be set in SMB2 request */
if (ses->sign)
req->SecurityMode = cpu_to_le16(SMB2_NEGOTIATE_SIGNING_REQUIRED);
else if (global_secflags & CIFSSEC_MAY_SIGN)
req->SecurityMode = cpu_to_le16(SMB2_NEGOTIATE_SIGNING_ENABLED);
else
req->SecurityMode = 0;
req->Capabilities = cpu_to_le32(server->vals->req_capabilities);
if (ses->chan_max > 1)
req->Capabilities |= cpu_to_le32(SMB2_GLOBAL_CAP_MULTI_CHANNEL);
/* ClientGUID must be zero for SMB2.02 dialect */
if (server->vals->protocol_id == SMB20_PROT_ID)
memset(req->ClientGUID, 0, SMB2_CLIENT_GUID_SIZE);
else {
memcpy(req->ClientGUID, server->client_guid,
SMB2_CLIENT_GUID_SIZE);
if ((server->vals->protocol_id == SMB311_PROT_ID) ||
(strcmp(server->vals->version_string,
SMB3ANY_VERSION_STRING) == 0) ||
(strcmp(server->vals->version_string,
SMBDEFAULT_VERSION_STRING) == 0))
assemble_neg_contexts(req, server, &total_len);
}
iov[0].iov_base = (char *)req;
iov[0].iov_len = total_len;
memset(&rqst, 0, sizeof(struct smb_rqst));
rqst.rq_iov = iov;
rqst.rq_nvec = 1;
rc = cifs_send_recv(xid, ses, server,
&rqst, &resp_buftype, flags, &rsp_iov);
cifs_small_buf_release(req);
rsp = (struct smb2_negotiate_rsp *)rsp_iov.iov_base;
/*
* No tcon so can't do
* cifs_stats_inc(&tcon->stats.smb2_stats.smb2_com_fail[SMB2...]);
*/
if (rc == -EOPNOTSUPP) {
cifs_server_dbg(VFS, "Dialect not supported by server. Consider specifying vers=1.0 or vers=2.0 on mount for accessing older servers\n");
goto neg_exit;
} else if (rc != 0)
goto neg_exit;
if (strcmp(server->vals->version_string,
SMB3ANY_VERSION_STRING) == 0) {
if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) {
cifs_server_dbg(VFS,
"SMB2 dialect returned but not requested\n");
return -EIO;
} else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) {
cifs_server_dbg(VFS,
"SMB2.1 dialect returned but not requested\n");
return -EIO;
} else if (rsp->DialectRevision == cpu_to_le16(SMB311_PROT_ID)) {
/* ops set to 3.0 by default for default so update */
server->ops = &smb311_operations;
server->vals = &smb311_values;
}
} else if (strcmp(server->vals->version_string,
SMBDEFAULT_VERSION_STRING) == 0) {
if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) {
cifs_server_dbg(VFS,
"SMB2 dialect returned but not requested\n");
return -EIO;
} else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) {
/* ops set to 3.0 by default for default so update */
server->ops = &smb21_operations;
server->vals = &smb21_values;
} else if (rsp->DialectRevision == cpu_to_le16(SMB311_PROT_ID)) {
server->ops = &smb311_operations;
server->vals = &smb311_values;
}
} else if (le16_to_cpu(rsp->DialectRevision) !=
server->vals->protocol_id) {
/* if requested single dialect ensure returned dialect matched */
cifs_server_dbg(VFS, "Invalid 0x%x dialect returned: not requested\n",
le16_to_cpu(rsp->DialectRevision));
return -EIO;
}
cifs_dbg(FYI, "mode 0x%x\n", rsp->SecurityMode);
if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID))
cifs_dbg(FYI, "negotiated smb2.0 dialect\n");
else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID))