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#include <linux/fs.h>
26#include <linux/list.h>
27#include <linux/wait.h>
28#include <linux/net.h>
29#include <linux/delay.h>
30#include <linux/uaccess.h>
31#include <asm/processor.h>
32#include <linux/mempool.h>
33#include <linux/highmem.h>
34#include <crypto/aead.h>
35#include "smb2pdu.h"
36#include "cifsglob.h"
37#include "cifsproto.h"
38#include "smb2proto.h"
39#include "cifs_debug.h"
40#include "smb2status.h"
41#include "smb2glob.h"
42
43static int
44smb2_crypto_shash_allocate(struct TCP_Server_Info *server)
45{
46 int rc;
47 unsigned int size;
48
49 if (server->secmech.sdeschmacsha256 != NULL)
50 return 0;
51
52 server->secmech.hmacsha256 = crypto_alloc_shash("hmac(sha256)", 0, 0);
53 if (IS_ERR(server->secmech.hmacsha256)) {
54 cifs_dbg(VFS, "could not allocate crypto hmacsha256\n");
55 rc = PTR_ERR(server->secmech.hmacsha256);
56 server->secmech.hmacsha256 = NULL;
57 return rc;
58 }
59
60 size = sizeof(struct shash_desc) +
61 crypto_shash_descsize(server->secmech.hmacsha256);
62 server->secmech.sdeschmacsha256 = kmalloc(size, GFP_KERNEL);
63 if (!server->secmech.sdeschmacsha256) {
64 crypto_free_shash(server->secmech.hmacsha256);
65 server->secmech.hmacsha256 = NULL;
66 return -ENOMEM;
67 }
68 server->secmech.sdeschmacsha256->shash.tfm = server->secmech.hmacsha256;
69 server->secmech.sdeschmacsha256->shash.flags = 0x0;
70
71 return 0;
72}
73
74static int
75smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
76{
77 unsigned int size;
78 int rc;
79
80 if (server->secmech.sdesccmacaes != NULL)
81 return 0;
82
83 rc = smb2_crypto_shash_allocate(server);
84 if (rc)
85 return rc;
86
87 server->secmech.cmacaes = crypto_alloc_shash("cmac(aes)", 0, 0);
88 if (IS_ERR(server->secmech.cmacaes)) {
89 cifs_dbg(VFS, "could not allocate crypto cmac-aes");
90 kfree(server->secmech.sdeschmacsha256);
91 server->secmech.sdeschmacsha256 = NULL;
92 crypto_free_shash(server->secmech.hmacsha256);
93 server->secmech.hmacsha256 = NULL;
94 rc = PTR_ERR(server->secmech.cmacaes);
95 server->secmech.cmacaes = NULL;
96 return rc;
97 }
98
99 size = sizeof(struct shash_desc) +
100 crypto_shash_descsize(server->secmech.cmacaes);
101 server->secmech.sdesccmacaes = kmalloc(size, GFP_KERNEL);
102 if (!server->secmech.sdesccmacaes) {
103 cifs_dbg(VFS, "%s: Can't alloc cmacaes\n", __func__);
104 kfree(server->secmech.sdeschmacsha256);
105 server->secmech.sdeschmacsha256 = NULL;
106 crypto_free_shash(server->secmech.hmacsha256);
107 crypto_free_shash(server->secmech.cmacaes);
108 server->secmech.hmacsha256 = NULL;
109 server->secmech.cmacaes = NULL;
110 return -ENOMEM;
111 }
112 server->secmech.sdesccmacaes->shash.tfm = server->secmech.cmacaes;
113 server->secmech.sdesccmacaes->shash.flags = 0x0;
114
115 return 0;
116}
117
118static struct cifs_ses *
119smb2_find_smb_ses_unlocked(struct TCP_Server_Info *server, __u64 ses_id)
120{
121 struct cifs_ses *ses;
122
123 list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
124 if (ses->Suid != ses_id)
125 continue;
126 return ses;
127 }
128
129 return NULL;
130}
131
132struct cifs_ses *
133smb2_find_smb_ses(struct TCP_Server_Info *server, __u64 ses_id)
134{
135 struct cifs_ses *ses;
136
137 spin_lock(&cifs_tcp_ses_lock);
138 ses = smb2_find_smb_ses_unlocked(server, ses_id);
139 spin_unlock(&cifs_tcp_ses_lock);
140
141 return ses;
142}
143
144static struct cifs_tcon *
145smb2_find_smb_sess_tcon_unlocked(struct cifs_ses *ses, __u32 tid)
146{
147 struct cifs_tcon *tcon;
148
149 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
150 if (tcon->tid != tid)
151 continue;
152 ++tcon->tc_count;
153 return tcon;
154 }
155
156 return NULL;
157}
158
159
160
161
162
163
164struct cifs_tcon *
165smb2_find_smb_tcon(struct TCP_Server_Info *server, __u64 ses_id, __u32 tid)
166{
167 struct cifs_ses *ses;
168 struct cifs_tcon *tcon;
169
170 spin_lock(&cifs_tcp_ses_lock);
171 ses = smb2_find_smb_ses_unlocked(server, ses_id);
172 if (!ses) {
173 spin_unlock(&cifs_tcp_ses_lock);
174 return NULL;
175 }
176 tcon = smb2_find_smb_sess_tcon_unlocked(ses, tid);
177 spin_unlock(&cifs_tcp_ses_lock);
178
179 return tcon;
180}
181
182int
183smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
184{
185 int rc;
186 unsigned char smb2_signature[SMB2_HMACSHA256_SIZE];
187 unsigned char *sigptr = smb2_signature;
188 struct kvec *iov = rqst->rq_iov;
189 struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)iov[1].iov_base;
190 struct cifs_ses *ses;
191
192 ses = smb2_find_smb_ses(server, shdr->SessionId);
193 if (!ses) {
194 cifs_dbg(VFS, "%s: Could not find session\n", __func__);
195 return 0;
196 }
197
198 memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
199 memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
200
201 rc = smb2_crypto_shash_allocate(server);
202 if (rc) {
203 cifs_dbg(VFS, "%s: shah256 alloc failed\n", __func__);
204 return rc;
205 }
206
207 rc = crypto_shash_setkey(server->secmech.hmacsha256,
208 ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
209 if (rc) {
210 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
211 return rc;
212 }
213
214 rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
215 if (rc) {
216 cifs_dbg(VFS, "%s: Could not init sha256", __func__);
217 return rc;
218 }
219
220 rc = __cifs_calc_signature(rqst, server, sigptr,
221 &server->secmech.sdeschmacsha256->shash);
222
223 if (!rc)
224 memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
225
226 return rc;
227}
228
229static int generate_key(struct cifs_ses *ses, struct kvec label,
230 struct kvec context, __u8 *key, unsigned int key_size)
231{
232 unsigned char zero = 0x0;
233 __u8 i[4] = {0, 0, 0, 1};
234 __u8 L[4] = {0, 0, 0, 128};
235 int rc = 0;
236 unsigned char prfhash[SMB2_HMACSHA256_SIZE];
237 unsigned char *hashptr = prfhash;
238
239 memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
240 memset(key, 0x0, key_size);
241
242 rc = smb3_crypto_shash_allocate(ses->server);
243 if (rc) {
244 cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
245 goto smb3signkey_ret;
246 }
247
248 rc = crypto_shash_setkey(ses->server->secmech.hmacsha256,
249 ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
250 if (rc) {
251 cifs_dbg(VFS, "%s: Could not set with session key\n", __func__);
252 goto smb3signkey_ret;
253 }
254
255 rc = crypto_shash_init(&ses->server->secmech.sdeschmacsha256->shash);
256 if (rc) {
257 cifs_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
258 goto smb3signkey_ret;
259 }
260
261 rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
262 i, 4);
263 if (rc) {
264 cifs_dbg(VFS, "%s: Could not update with n\n", __func__);
265 goto smb3signkey_ret;
266 }
267
268 rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
269 label.iov_base, label.iov_len);
270 if (rc) {
271 cifs_dbg(VFS, "%s: Could not update with label\n", __func__);
272 goto smb3signkey_ret;
273 }
274
275 rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
276 &zero, 1);
277 if (rc) {
278 cifs_dbg(VFS, "%s: Could not update with zero\n", __func__);
279 goto smb3signkey_ret;
280 }
281
282 rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
283 context.iov_base, context.iov_len);
284 if (rc) {
285 cifs_dbg(VFS, "%s: Could not update with context\n", __func__);
286 goto smb3signkey_ret;
287 }
288
289 rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
290 L, 4);
291 if (rc) {
292 cifs_dbg(VFS, "%s: Could not update with L\n", __func__);
293 goto smb3signkey_ret;
294 }
295
296 rc = crypto_shash_final(&ses->server->secmech.sdeschmacsha256->shash,
297 hashptr);
298 if (rc) {
299 cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
300 goto smb3signkey_ret;
301 }
302
303 memcpy(key, hashptr, key_size);
304
305smb3signkey_ret:
306 return rc;
307}
308
309struct derivation {
310 struct kvec label;
311 struct kvec context;
312};
313
314struct derivation_triplet {
315 struct derivation signing;
316 struct derivation encryption;
317 struct derivation decryption;
318};
319
320static int
321generate_smb3signingkey(struct cifs_ses *ses,
322 const struct derivation_triplet *ptriplet)
323{
324 int rc;
325
326 rc = generate_key(ses, ptriplet->signing.label,
327 ptriplet->signing.context, ses->smb3signingkey,
328 SMB3_SIGN_KEY_SIZE);
329 if (rc)
330 return rc;
331
332 rc = generate_key(ses, ptriplet->encryption.label,
333 ptriplet->encryption.context, ses->smb3encryptionkey,
334 SMB3_SIGN_KEY_SIZE);
335 if (rc)
336 return rc;
337
338 return generate_key(ses, ptriplet->decryption.label,
339 ptriplet->decryption.context,
340 ses->smb3decryptionkey, SMB3_SIGN_KEY_SIZE);
341}
342
343int
344generate_smb30signingkey(struct cifs_ses *ses)
345
346{
347 struct derivation_triplet triplet;
348 struct derivation *d;
349
350 d = &triplet.signing;
351 d->label.iov_base = "SMB2AESCMAC";
352 d->label.iov_len = 12;
353 d->context.iov_base = "SmbSign";
354 d->context.iov_len = 8;
355
356 d = &triplet.encryption;
357 d->label.iov_base = "SMB2AESCCM";
358 d->label.iov_len = 11;
359 d->context.iov_base = "ServerIn ";
360 d->context.iov_len = 10;
361
362 d = &triplet.decryption;
363 d->label.iov_base = "SMB2AESCCM";
364 d->label.iov_len = 11;
365 d->context.iov_base = "ServerOut";
366 d->context.iov_len = 10;
367
368 return generate_smb3signingkey(ses, &triplet);
369}
370
371int
372generate_smb311signingkey(struct cifs_ses *ses)
373
374{
375 struct derivation_triplet triplet;
376 struct derivation *d;
377
378 d = &triplet.signing;
379 d->label.iov_base = "SMB2AESCMAC";
380 d->label.iov_len = 12;
381 d->context.iov_base = "SmbSign";
382 d->context.iov_len = 8;
383
384 d = &triplet.encryption;
385 d->label.iov_base = "SMB2AESCCM";
386 d->label.iov_len = 11;
387 d->context.iov_base = "ServerIn ";
388 d->context.iov_len = 10;
389
390 d = &triplet.decryption;
391 d->label.iov_base = "SMB2AESCCM";
392 d->label.iov_len = 11;
393 d->context.iov_base = "ServerOut";
394 d->context.iov_len = 10;
395
396 return generate_smb3signingkey(ses, &triplet);
397}
398
399int
400smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
401{
402 int rc = 0;
403 unsigned char smb3_signature[SMB2_CMACAES_SIZE];
404 unsigned char *sigptr = smb3_signature;
405 struct kvec *iov = rqst->rq_iov;
406 struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)iov[1].iov_base;
407 struct cifs_ses *ses;
408
409 ses = smb2_find_smb_ses(server, shdr->SessionId);
410 if (!ses) {
411 cifs_dbg(VFS, "%s: Could not find session\n", __func__);
412 return 0;
413 }
414
415 memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
416 memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
417
418 rc = crypto_shash_setkey(server->secmech.cmacaes,
419 ses->smb3signingkey, SMB2_CMACAES_SIZE);
420
421 if (rc) {
422 cifs_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__);
423 return rc;
424 }
425
426
427
428
429
430
431 rc = crypto_shash_init(&server->secmech.sdesccmacaes->shash);
432 if (rc) {
433 cifs_dbg(VFS, "%s: Could not init cmac aes\n", __func__);
434 return rc;
435 }
436
437 rc = __cifs_calc_signature(rqst, server, sigptr,
438 &server->secmech.sdesccmacaes->shash);
439
440 if (!rc)
441 memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
442
443 return rc;
444}
445
446
447static int
448smb2_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server)
449{
450 int rc = 0;
451 struct smb2_sync_hdr *shdr =
452 (struct smb2_sync_hdr *)rqst->rq_iov[1].iov_base;
453
454 if (!(shdr->Flags & SMB2_FLAGS_SIGNED) ||
455 server->tcpStatus == CifsNeedNegotiate)
456 return rc;
457
458 if (!server->session_estab) {
459 strncpy(shdr->Signature, "BSRSPYL", 8);
460 return rc;
461 }
462
463 rc = server->ops->calc_signature(rqst, server);
464
465 return rc;
466}
467
468int
469smb2_verify_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
470{
471 unsigned int rc;
472 char server_response_sig[16];
473 struct smb2_sync_hdr *shdr =
474 (struct smb2_sync_hdr *)rqst->rq_iov[1].iov_base;
475
476 if ((shdr->Command == SMB2_NEGOTIATE) ||
477 (shdr->Command == SMB2_SESSION_SETUP) ||
478 (shdr->Command == SMB2_OPLOCK_BREAK) ||
479 (!server->session_estab))
480 return 0;
481
482
483
484
485
486
487
488 if (memcmp(shdr->Signature, "BSRSPYL ", 8) == 0)
489 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
490 shdr->Command);
491
492
493
494
495
496 memcpy(server_response_sig, shdr->Signature, SMB2_SIGNATURE_SIZE);
497
498 memset(shdr->Signature, 0, SMB2_SIGNATURE_SIZE);
499
500 mutex_lock(&server->srv_mutex);
501 rc = server->ops->calc_signature(rqst, server);
502 mutex_unlock(&server->srv_mutex);
503
504 if (rc)
505 return rc;
506
507 if (memcmp(server_response_sig, shdr->Signature, SMB2_SIGNATURE_SIZE))
508 return -EACCES;
509 else
510 return 0;
511}
512
513
514
515
516
517static inline void
518smb2_seq_num_into_buf(struct TCP_Server_Info *server,
519 struct smb2_sync_hdr *shdr)
520{
521 unsigned int i, num = le16_to_cpu(shdr->CreditCharge);
522
523 shdr->MessageId = get_next_mid64(server);
524
525 for (i = 1; i < num; i++)
526 get_next_mid(server);
527}
528
529static struct mid_q_entry *
530smb2_mid_entry_alloc(const struct smb2_sync_hdr *shdr,
531 struct TCP_Server_Info *server)
532{
533 struct mid_q_entry *temp;
534
535 if (server == NULL) {
536 cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n");
537 return NULL;
538 }
539
540 temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
541 if (temp == NULL)
542 return temp;
543 else {
544 memset(temp, 0, sizeof(struct mid_q_entry));
545 temp->mid = le64_to_cpu(shdr->MessageId);
546 temp->pid = current->pid;
547 temp->command = shdr->Command;
548 temp->when_alloc = jiffies;
549 temp->server = server;
550
551
552
553
554
555 temp->callback = cifs_wake_up_task;
556 temp->callback_data = current;
557 }
558
559 atomic_inc(&midCount);
560 temp->mid_state = MID_REQUEST_ALLOCATED;
561 return temp;
562}
563
564static int
565smb2_get_mid_entry(struct cifs_ses *ses, struct smb2_sync_hdr *shdr,
566 struct mid_q_entry **mid)
567{
568 if (ses->server->tcpStatus == CifsExiting)
569 return -ENOENT;
570
571 if (ses->server->tcpStatus == CifsNeedReconnect) {
572 cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
573 return -EAGAIN;
574 }
575
576 if (ses->status == CifsNew) {
577 if ((shdr->Command != SMB2_SESSION_SETUP) &&
578 (shdr->Command != SMB2_NEGOTIATE))
579 return -EAGAIN;
580
581 }
582
583 if (ses->status == CifsExiting) {
584 if (shdr->Command != SMB2_LOGOFF)
585 return -EAGAIN;
586
587 }
588
589 *mid = smb2_mid_entry_alloc(shdr, ses->server);
590 if (*mid == NULL)
591 return -ENOMEM;
592 spin_lock(&GlobalMid_Lock);
593 list_add_tail(&(*mid)->qhead, &ses->server->pending_mid_q);
594 spin_unlock(&GlobalMid_Lock);
595 return 0;
596}
597
598int
599smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
600 bool log_error)
601{
602 unsigned int len = get_rfc1002_length(mid->resp_buf);
603 struct kvec iov[2];
604 struct smb_rqst rqst = { .rq_iov = iov,
605 .rq_nvec = 2 };
606
607 iov[0].iov_base = (char *)mid->resp_buf;
608 iov[0].iov_len = 4;
609 iov[1].iov_base = (char *)mid->resp_buf + 4;
610 iov[1].iov_len = len;
611
612 dump_smb(mid->resp_buf, min_t(u32, 80, len));
613
614 if (len > 24 && server->sign && !mid->decrypted) {
615 int rc;
616
617 rc = smb2_verify_signature(&rqst, server);
618 if (rc)
619 cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
620 rc);
621 }
622
623 return map_smb2_to_linux_error(mid->resp_buf, log_error);
624}
625
626struct mid_q_entry *
627smb2_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
628{
629 int rc;
630 struct smb2_sync_hdr *shdr =
631 (struct smb2_sync_hdr *)rqst->rq_iov[1].iov_base;
632 struct mid_q_entry *mid;
633
634 smb2_seq_num_into_buf(ses->server, shdr);
635
636 rc = smb2_get_mid_entry(ses, shdr, &mid);
637 if (rc)
638 return ERR_PTR(rc);
639 rc = smb2_sign_rqst(rqst, ses->server);
640 if (rc) {
641 cifs_delete_mid(mid);
642 return ERR_PTR(rc);
643 }
644 return mid;
645}
646
647struct mid_q_entry *
648smb2_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
649{
650 int rc;
651 struct smb2_sync_hdr *shdr =
652 (struct smb2_sync_hdr *)rqst->rq_iov[1].iov_base;
653 struct mid_q_entry *mid;
654
655 smb2_seq_num_into_buf(server, shdr);
656
657 mid = smb2_mid_entry_alloc(shdr, server);
658 if (mid == NULL)
659 return ERR_PTR(-ENOMEM);
660
661 rc = smb2_sign_rqst(rqst, server);
662 if (rc) {
663 DeleteMidQEntry(mid);
664 return ERR_PTR(rc);
665 }
666
667 return mid;
668}
669
670int
671smb3_crypto_aead_allocate(struct TCP_Server_Info *server)
672{
673 struct crypto_aead *tfm;
674
675 if (!server->secmech.ccmaesencrypt) {
676 tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
677 if (IS_ERR(tfm)) {
678 cifs_dbg(VFS, "%s: Failed to alloc encrypt aead\n",
679 __func__);
680 return PTR_ERR(tfm);
681 }
682 server->secmech.ccmaesencrypt = tfm;
683 }
684
685 if (!server->secmech.ccmaesdecrypt) {
686 tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
687 if (IS_ERR(tfm)) {
688 crypto_free_aead(server->secmech.ccmaesencrypt);
689 server->secmech.ccmaesencrypt = NULL;
690 cifs_dbg(VFS, "%s: Failed to alloc decrypt aead\n",
691 __func__);
692 return PTR_ERR(tfm);
693 }
694 server->secmech.ccmaesdecrypt = tfm;
695 }
696
697 return 0;
698}
699
