1 /*
2 * fs/cifs/smb2transport.c
3 *
4 * Copyright (C) International Business Machines Corp., 2002, 2011
5 * Etersoft, 2012
6 * Author(s): Steve French (sfrench@us.ibm.com)
7 * Jeremy Allison (jra@samba.org) 2006
8 * Pavel Shilovsky (pshilovsky@samba.org) 2012
9 *
10 * This library is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License as published
12 * by the Free Software Foundation; either version 2.1 of the License, or
13 * (at your option) any later version.
14 *
15 * This library is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
18 * the GNU Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this library; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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
43 static int
smb3_crypto_shash_allocate(struct TCP_Server_Info * server)44 smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
45 {
46 struct cifs_secmech *p = &server->secmech;
47 int rc;
48
49 rc = cifs_alloc_hash("hmac(sha256)",
50 &p->hmacsha256,
51 &p->sdeschmacsha256);
52 if (rc)
53 goto err;
54
55 rc = cifs_alloc_hash("cmac(aes)", &p->cmacaes, &p->sdesccmacaes);
56 if (rc)
57 goto err;
58
59 return 0;
60 err:
61 cifs_free_hash(&p->hmacsha256, &p->sdeschmacsha256);
62 return rc;
63 }
64
65 int
smb311_crypto_shash_allocate(struct TCP_Server_Info * server)66 smb311_crypto_shash_allocate(struct TCP_Server_Info *server)
67 {
68 struct cifs_secmech *p = &server->secmech;
69 int rc = 0;
70
71 rc = cifs_alloc_hash("hmac(sha256)",
72 &p->hmacsha256,
73 &p->sdeschmacsha256);
74 if (rc)
75 return rc;
76
77 rc = cifs_alloc_hash("cmac(aes)", &p->cmacaes, &p->sdesccmacaes);
78 if (rc)
79 goto err;
80
81 rc = cifs_alloc_hash("sha512", &p->sha512, &p->sdescsha512);
82 if (rc)
83 goto err;
84
85 return 0;
86
87 err:
88 cifs_free_hash(&p->cmacaes, &p->sdesccmacaes);
89 cifs_free_hash(&p->hmacsha256, &p->sdeschmacsha256);
90 return rc;
91 }
92
93
94 static
smb2_get_sign_key(__u64 ses_id,struct TCP_Server_Info * server,u8 * key)95 int smb2_get_sign_key(__u64 ses_id, struct TCP_Server_Info *server, u8 *key)
96 {
97 struct cifs_chan *chan;
98 struct cifs_ses *ses = NULL;
99 struct TCP_Server_Info *it = NULL;
100 int i;
101 int rc = 0;
102
103 spin_lock(&cifs_tcp_ses_lock);
104
105 list_for_each_entry(it, &cifs_tcp_ses_list, tcp_ses_list) {
106 list_for_each_entry(ses, &it->smb_ses_list, smb_ses_list) {
107 if (ses->Suid == ses_id)
108 goto found;
109 }
110 }
111 cifs_server_dbg(VFS, "%s: Could not find session 0x%llx\n",
112 __func__, ses_id);
113 rc = -ENOENT;
114 goto out;
115
116 found:
117 if (ses->binding) {
118 /*
119 * If we are in the process of binding a new channel
120 * to an existing session, use the master connection
121 * session key
122 */
123 memcpy(key, ses->smb3signingkey, SMB3_SIGN_KEY_SIZE);
124 goto out;
125 }
126
127 /*
128 * Otherwise, use the channel key.
129 */
130
131 for (i = 0; i < ses->chan_count; i++) {
132 chan = ses->chans + i;
133 if (chan->server == server) {
134 memcpy(key, chan->signkey, SMB3_SIGN_KEY_SIZE);
135 goto out;
136 }
137 }
138
139 cifs_dbg(VFS,
140 "%s: Could not find channel signing key for session 0x%llx\n",
141 __func__, ses_id);
142 rc = -ENOENT;
143
144 out:
145 spin_unlock(&cifs_tcp_ses_lock);
146 return rc;
147 }
148
149 static struct cifs_ses *
smb2_find_smb_ses_unlocked(struct TCP_Server_Info * server,__u64 ses_id)150 smb2_find_smb_ses_unlocked(struct TCP_Server_Info *server, __u64 ses_id)
151 {
152 struct cifs_ses *ses;
153
154 list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
155 if (ses->Suid != ses_id)
156 continue;
157 return ses;
158 }
159
160 return NULL;
161 }
162
163 struct cifs_ses *
smb2_find_smb_ses(struct TCP_Server_Info * server,__u64 ses_id)164 smb2_find_smb_ses(struct TCP_Server_Info *server, __u64 ses_id)
165 {
166 struct cifs_ses *ses;
167
168 spin_lock(&cifs_tcp_ses_lock);
169 ses = smb2_find_smb_ses_unlocked(server, ses_id);
170 spin_unlock(&cifs_tcp_ses_lock);
171
172 return ses;
173 }
174
175 static struct cifs_tcon *
smb2_find_smb_sess_tcon_unlocked(struct cifs_ses * ses,__u32 tid)176 smb2_find_smb_sess_tcon_unlocked(struct cifs_ses *ses, __u32 tid)
177 {
178 struct cifs_tcon *tcon;
179
180 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
181 if (tcon->tid != tid)
182 continue;
183 ++tcon->tc_count;
184 return tcon;
185 }
186
187 return NULL;
188 }
189
190 /*
191 * Obtain tcon corresponding to the tid in the given
192 * cifs_ses
193 */
194
195 struct cifs_tcon *
smb2_find_smb_tcon(struct TCP_Server_Info * server,__u64 ses_id,__u32 tid)196 smb2_find_smb_tcon(struct TCP_Server_Info *server, __u64 ses_id, __u32 tid)
197 {
198 struct cifs_ses *ses;
199 struct cifs_tcon *tcon;
200
201 spin_lock(&cifs_tcp_ses_lock);
202 ses = smb2_find_smb_ses_unlocked(server, ses_id);
203 if (!ses) {
204 spin_unlock(&cifs_tcp_ses_lock);
205 return NULL;
206 }
207 tcon = smb2_find_smb_sess_tcon_unlocked(ses, tid);
208 spin_unlock(&cifs_tcp_ses_lock);
209
210 return tcon;
211 }
212
213 int
smb2_calc_signature(struct smb_rqst * rqst,struct TCP_Server_Info * server,bool allocate_crypto)214 smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
215 bool allocate_crypto)
216 {
217 int rc;
218 unsigned char smb2_signature[SMB2_HMACSHA256_SIZE];
219 unsigned char *sigptr = smb2_signature;
220 struct kvec *iov = rqst->rq_iov;
221 struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)iov[0].iov_base;
222 struct cifs_ses *ses;
223 struct shash_desc *shash;
224 struct crypto_shash *hash;
225 struct sdesc *sdesc = NULL;
226 struct smb_rqst drqst;
227
228 ses = smb2_find_smb_ses(server, shdr->SessionId);
229 if (!ses) {
230 cifs_server_dbg(VFS, "%s: Could not find session\n", __func__);
231 return 0;
232 }
233
234 memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
235 memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
236
237 if (allocate_crypto) {
238 rc = cifs_alloc_hash("hmac(sha256)", &hash, &sdesc);
239 if (rc) {
240 cifs_server_dbg(VFS,
241 "%s: sha256 alloc failed\n", __func__);
242 return rc;
243 }
244 shash = &sdesc->shash;
245 } else {
246 hash = server->secmech.hmacsha256;
247 shash = &server->secmech.sdeschmacsha256->shash;
248 }
249
250 rc = crypto_shash_setkey(hash, ses->auth_key.response,
251 SMB2_NTLMV2_SESSKEY_SIZE);
252 if (rc) {
253 cifs_server_dbg(VFS,
254 "%s: Could not update with response\n",
255 __func__);
256 goto out;
257 }
258
259 rc = crypto_shash_init(shash);
260 if (rc) {
261 cifs_server_dbg(VFS, "%s: Could not init sha256", __func__);
262 goto out;
263 }
264
265 /*
266 * For SMB2+, __cifs_calc_signature() expects to sign only the actual
267 * data, that is, iov[0] should not contain a rfc1002 length.
268 *
269 * Sign the rfc1002 length prior to passing the data (iov[1-N]) down to
270 * __cifs_calc_signature().
271 */
272 drqst = *rqst;
273 if (drqst.rq_nvec >= 2 && iov[0].iov_len == 4) {
274 rc = crypto_shash_update(shash, iov[0].iov_base,
275 iov[0].iov_len);
276 if (rc) {
277 cifs_server_dbg(VFS,
278 "%s: Could not update with payload\n",
279 __func__);
280 goto out;
281 }
282 drqst.rq_iov++;
283 drqst.rq_nvec--;
284 }
285
286 rc = __cifs_calc_signature(&drqst, server, sigptr, shash);
287 if (!rc)
288 memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
289
290 out:
291 if (allocate_crypto)
292 cifs_free_hash(&hash, &sdesc);
293 return rc;
294 }
295
generate_key(struct cifs_ses * ses,struct kvec label,struct kvec context,__u8 * key,unsigned int key_size)296 static int generate_key(struct cifs_ses *ses, struct kvec label,
297 struct kvec context, __u8 *key, unsigned int key_size)
298 {
299 unsigned char zero = 0x0;
300 __u8 i[4] = {0, 0, 0, 1};
301 __u8 L[4] = {0, 0, 0, 128};
302 int rc = 0;
303 unsigned char prfhash[SMB2_HMACSHA256_SIZE];
304 unsigned char *hashptr = prfhash;
305 struct TCP_Server_Info *server = ses->server;
306
307 memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
308 memset(key, 0x0, key_size);
309
310 rc = smb3_crypto_shash_allocate(server);
311 if (rc) {
312 cifs_server_dbg(VFS, "%s: crypto alloc failed\n", __func__);
313 goto smb3signkey_ret;
314 }
315
316 rc = crypto_shash_setkey(server->secmech.hmacsha256,
317 ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
318 if (rc) {
319 cifs_server_dbg(VFS, "%s: Could not set with session key\n", __func__);
320 goto smb3signkey_ret;
321 }
322
323 rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
324 if (rc) {
325 cifs_server_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
326 goto smb3signkey_ret;
327 }
328
329 rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
330 i, 4);
331 if (rc) {
332 cifs_server_dbg(VFS, "%s: Could not update with n\n", __func__);
333 goto smb3signkey_ret;
334 }
335
336 rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
337 label.iov_base, label.iov_len);
338 if (rc) {
339 cifs_server_dbg(VFS, "%s: Could not update with label\n", __func__);
340 goto smb3signkey_ret;
341 }
342
343 rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
344 &zero, 1);
345 if (rc) {
346 cifs_server_dbg(VFS, "%s: Could not update with zero\n", __func__);
347 goto smb3signkey_ret;
348 }
349
350 rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
351 context.iov_base, context.iov_len);
352 if (rc) {
353 cifs_server_dbg(VFS, "%s: Could not update with context\n", __func__);
354 goto smb3signkey_ret;
355 }
356
357 rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
358 L, 4);
359 if (rc) {
360 cifs_server_dbg(VFS, "%s: Could not update with L\n", __func__);
361 goto smb3signkey_ret;
362 }
363
364 rc = crypto_shash_final(&server->secmech.sdeschmacsha256->shash,
365 hashptr);
366 if (rc) {
367 cifs_server_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
368 goto smb3signkey_ret;
369 }
370
371 memcpy(key, hashptr, key_size);
372
373 smb3signkey_ret:
374 return rc;
375 }
376
377 struct derivation {
378 struct kvec label;
379 struct kvec context;
380 };
381
382 struct derivation_triplet {
383 struct derivation signing;
384 struct derivation encryption;
385 struct derivation decryption;
386 };
387
388 static int
generate_smb3signingkey(struct cifs_ses * ses,const struct derivation_triplet * ptriplet)389 generate_smb3signingkey(struct cifs_ses *ses,
390 const struct derivation_triplet *ptriplet)
391 {
392 int rc;
393
394 /*
395 * All channels use the same encryption/decryption keys but
396 * they have their own signing key.
397 *
398 * When we generate the keys, check if it is for a new channel
399 * (binding) in which case we only need to generate a signing
400 * key and store it in the channel as to not overwrite the
401 * master connection signing key stored in the session
402 */
403
404 if (ses->binding) {
405 rc = generate_key(ses, ptriplet->signing.label,
406 ptriplet->signing.context,
407 cifs_ses_binding_channel(ses)->signkey,
408 SMB3_SIGN_KEY_SIZE);
409 if (rc)
410 return rc;
411 } else {
412 rc = generate_key(ses, ptriplet->signing.label,
413 ptriplet->signing.context,
414 ses->smb3signingkey,
415 SMB3_SIGN_KEY_SIZE);
416 if (rc)
417 return rc;
418
419 memcpy(ses->chans[0].signkey, ses->smb3signingkey,
420 SMB3_SIGN_KEY_SIZE);
421
422 rc = generate_key(ses, ptriplet->encryption.label,
423 ptriplet->encryption.context,
424 ses->smb3encryptionkey,
425 SMB3_SIGN_KEY_SIZE);
426 rc = generate_key(ses, ptriplet->decryption.label,
427 ptriplet->decryption.context,
428 ses->smb3decryptionkey,
429 SMB3_SIGN_KEY_SIZE);
430 if (rc)
431 return rc;
432 }
433
434 if (rc)
435 return rc;
436
437 #ifdef CONFIG_CIFS_DEBUG_DUMP_KEYS
438 cifs_dbg(VFS, "%s: dumping generated AES session keys\n", __func__);
439 /*
440 * The session id is opaque in terms of endianness, so we can't
441 * print it as a long long. we dump it as we got it on the wire
442 */
443 cifs_dbg(VFS, "Session Id %*ph\n", (int)sizeof(ses->Suid),
444 &ses->Suid);
445 cifs_dbg(VFS, "Session Key %*ph\n",
446 SMB2_NTLMV2_SESSKEY_SIZE, ses->auth_key.response);
447 cifs_dbg(VFS, "Signing Key %*ph\n",
448 SMB3_SIGN_KEY_SIZE, ses->smb3signingkey);
449 cifs_dbg(VFS, "ServerIn Key %*ph\n",
450 SMB3_SIGN_KEY_SIZE, ses->smb3encryptionkey);
451 cifs_dbg(VFS, "ServerOut Key %*ph\n",
452 SMB3_SIGN_KEY_SIZE, ses->smb3decryptionkey);
453 #endif
454 return rc;
455 }
456
457 int
generate_smb30signingkey(struct cifs_ses * ses)458 generate_smb30signingkey(struct cifs_ses *ses)
459
460 {
461 struct derivation_triplet triplet;
462 struct derivation *d;
463
464 d = &triplet.signing;
465 d->label.iov_base = "SMB2AESCMAC";
466 d->label.iov_len = 12;
467 d->context.iov_base = "SmbSign";
468 d->context.iov_len = 8;
469
470 d = &triplet.encryption;
471 d->label.iov_base = "SMB2AESCCM";
472 d->label.iov_len = 11;
473 d->context.iov_base = "ServerIn ";
474 d->context.iov_len = 10;
475
476 d = &triplet.decryption;
477 d->label.iov_base = "SMB2AESCCM";
478 d->label.iov_len = 11;
479 d->context.iov_base = "ServerOut";
480 d->context.iov_len = 10;
481
482 return generate_smb3signingkey(ses, &triplet);
483 }
484
485 int
generate_smb311signingkey(struct cifs_ses * ses)486 generate_smb311signingkey(struct cifs_ses *ses)
487
488 {
489 struct derivation_triplet triplet;
490 struct derivation *d;
491
492 d = &triplet.signing;
493 d->label.iov_base = "SMBSigningKey";
494 d->label.iov_len = 14;
495 d->context.iov_base = ses->preauth_sha_hash;
496 d->context.iov_len = 64;
497
498 d = &triplet.encryption;
499 d->label.iov_base = "SMBC2SCipherKey";
500 d->label.iov_len = 16;
501 d->context.iov_base = ses->preauth_sha_hash;
502 d->context.iov_len = 64;
503
504 d = &triplet.decryption;
505 d->label.iov_base = "SMBS2CCipherKey";
506 d->label.iov_len = 16;
507 d->context.iov_base = ses->preauth_sha_hash;
508 d->context.iov_len = 64;
509
510 return generate_smb3signingkey(ses, &triplet);
511 }
512
513 int
smb3_calc_signature(struct smb_rqst * rqst,struct TCP_Server_Info * server,bool allocate_crypto)514 smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
515 bool allocate_crypto)
516 {
517 int rc;
518 unsigned char smb3_signature[SMB2_CMACAES_SIZE];
519 unsigned char *sigptr = smb3_signature;
520 struct kvec *iov = rqst->rq_iov;
521 struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)iov[0].iov_base;
522 struct shash_desc *shash;
523 struct crypto_shash *hash;
524 struct sdesc *sdesc = NULL;
525 struct smb_rqst drqst;
526 u8 key[SMB3_SIGN_KEY_SIZE];
527
528 rc = smb2_get_sign_key(shdr->SessionId, server, key);
529 if (rc)
530 return 0;
531
532 if (allocate_crypto) {
533 rc = cifs_alloc_hash("cmac(aes)", &hash, &sdesc);
534 if (rc)
535 return rc;
536
537 shash = &sdesc->shash;
538 } else {
539 hash = server->secmech.cmacaes;
540 shash = &server->secmech.sdesccmacaes->shash;
541 }
542
543 memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
544 memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
545
546 rc = crypto_shash_setkey(hash, key, SMB2_CMACAES_SIZE);
547 if (rc) {
548 cifs_server_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__);
549 goto out;
550 }
551
552 /*
553 * we already allocate sdesccmacaes when we init smb3 signing key,
554 * so unlike smb2 case we do not have to check here if secmech are
555 * initialized
556 */
557 rc = crypto_shash_init(shash);
558 if (rc) {
559 cifs_server_dbg(VFS, "%s: Could not init cmac aes\n", __func__);
560 goto out;
561 }
562
563 /*
564 * For SMB2+, __cifs_calc_signature() expects to sign only the actual
565 * data, that is, iov[0] should not contain a rfc1002 length.
566 *
567 * Sign the rfc1002 length prior to passing the data (iov[1-N]) down to
568 * __cifs_calc_signature().
569 */
570 drqst = *rqst;
571 if (drqst.rq_nvec >= 2 && iov[0].iov_len == 4) {
572 rc = crypto_shash_update(shash, iov[0].iov_base,
573 iov[0].iov_len);
574 if (rc) {
575 cifs_server_dbg(VFS, "%s: Could not update with payload\n",
576 __func__);
577 goto out;
578 }
579 drqst.rq_iov++;
580 drqst.rq_nvec--;
581 }
582
583 rc = __cifs_calc_signature(&drqst, server, sigptr, shash);
584 if (!rc)
585 memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
586
587 out:
588 if (allocate_crypto)
589 cifs_free_hash(&hash, &sdesc);
590 return rc;
591 }
592
593 /* must be called with server->srv_mutex held */
594 static int
smb2_sign_rqst(struct smb_rqst * rqst,struct TCP_Server_Info * server)595 smb2_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server)
596 {
597 int rc = 0;
598 struct smb2_sync_hdr *shdr;
599 struct smb2_sess_setup_req *ssr;
600 bool is_binding;
601 bool is_signed;
602
603 shdr = (struct smb2_sync_hdr *)rqst->rq_iov[0].iov_base;
604 ssr = (struct smb2_sess_setup_req *)shdr;
605
606 is_binding = shdr->Command == SMB2_SESSION_SETUP &&
607 (ssr->Flags & SMB2_SESSION_REQ_FLAG_BINDING);
608 is_signed = shdr->Flags & SMB2_FLAGS_SIGNED;
609
610 if (!is_signed)
611 return 0;
612 if (server->tcpStatus == CifsNeedNegotiate)
613 return 0;
614 if (!is_binding && !server->session_estab) {
615 strncpy(shdr->Signature, "BSRSPYL", 8);
616 return 0;
617 }
618
619 rc = server->ops->calc_signature(rqst, server, false);
620
621 return rc;
622 }
623
624 int
smb2_verify_signature(struct smb_rqst * rqst,struct TCP_Server_Info * server)625 smb2_verify_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
626 {
627 unsigned int rc;
628 char server_response_sig[SMB2_SIGNATURE_SIZE];
629 struct smb2_sync_hdr *shdr =
630 (struct smb2_sync_hdr *)rqst->rq_iov[0].iov_base;
631
632 if ((shdr->Command == SMB2_NEGOTIATE) ||
633 (shdr->Command == SMB2_SESSION_SETUP) ||
634 (shdr->Command == SMB2_OPLOCK_BREAK) ||
635 server->ignore_signature ||
636 (!server->session_estab))
637 return 0;
638
639 /*
640 * BB what if signatures are supposed to be on for session but
641 * server does not send one? BB
642 */
643
644 /* Do not need to verify session setups with signature "BSRSPYL " */
645 if (memcmp(shdr->Signature, "BSRSPYL ", 8) == 0)
646 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
647 shdr->Command);
648
649 /*
650 * Save off the origiginal signature so we can modify the smb and check
651 * our calculated signature against what the server sent.
652 */
653 memcpy(server_response_sig, shdr->Signature, SMB2_SIGNATURE_SIZE);
654
655 memset(shdr->Signature, 0, SMB2_SIGNATURE_SIZE);
656
657 rc = server->ops->calc_signature(rqst, server, true);
658
659 if (rc)
660 return rc;
661
662 if (memcmp(server_response_sig, shdr->Signature, SMB2_SIGNATURE_SIZE)) {
663 cifs_dbg(VFS, "sign fail cmd 0x%x message id 0x%llx\n",
664 shdr->Command, shdr->MessageId);
665 return -EACCES;
666 } else
667 return 0;
668 }
669
670 /*
671 * Set message id for the request. Should be called after wait_for_free_request
672 * and when srv_mutex is held.
673 */
674 static inline void
smb2_seq_num_into_buf(struct TCP_Server_Info * server,struct smb2_sync_hdr * shdr)675 smb2_seq_num_into_buf(struct TCP_Server_Info *server,
676 struct smb2_sync_hdr *shdr)
677 {
678 unsigned int i, num = le16_to_cpu(shdr->CreditCharge);
679
680 shdr->MessageId = get_next_mid64(server);
681 /* skip message numbers according to CreditCharge field */
682 for (i = 1; i < num; i++)
683 get_next_mid(server);
684 }
685
686 static struct mid_q_entry *
smb2_mid_entry_alloc(const struct smb2_sync_hdr * shdr,struct TCP_Server_Info * server)687 smb2_mid_entry_alloc(const struct smb2_sync_hdr *shdr,
688 struct TCP_Server_Info *server)
689 {
690 struct mid_q_entry *temp;
691 unsigned int credits = le16_to_cpu(shdr->CreditCharge);
692
693 if (server == NULL) {
694 cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n");
695 return NULL;
696 }
697
698 temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
699 memset(temp, 0, sizeof(struct mid_q_entry));
700 kref_init(&temp->refcount);
701 temp->mid = le64_to_cpu(shdr->MessageId);
702 temp->credits = credits > 0 ? credits : 1;
703 temp->pid = current->pid;
704 temp->command = shdr->Command; /* Always LE */
705 temp->when_alloc = jiffies;
706 temp->server = server;
707
708 /*
709 * The default is for the mid to be synchronous, so the
710 * default callback just wakes up the current task.
711 */
712 get_task_struct(current);
713 temp->creator = current;
714 temp->callback = cifs_wake_up_task;
715 temp->callback_data = current;
716
717 atomic_inc(&midCount);
718 temp->mid_state = MID_REQUEST_ALLOCATED;
719 trace_smb3_cmd_enter(shdr->TreeId, shdr->SessionId,
720 le16_to_cpu(shdr->Command), temp->mid);
721 return temp;
722 }
723
724 static int
smb2_get_mid_entry(struct cifs_ses * ses,struct TCP_Server_Info * server,struct smb2_sync_hdr * shdr,struct mid_q_entry ** mid)725 smb2_get_mid_entry(struct cifs_ses *ses, struct TCP_Server_Info *server,
726 struct smb2_sync_hdr *shdr, struct mid_q_entry **mid)
727 {
728 if (server->tcpStatus == CifsExiting)
729 return -ENOENT;
730
731 if (server->tcpStatus == CifsNeedReconnect) {
732 cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
733 return -EAGAIN;
734 }
735
736 if (server->tcpStatus == CifsNeedNegotiate &&
737 shdr->Command != SMB2_NEGOTIATE)
738 return -EAGAIN;
739
740 if (ses->status == CifsNew) {
741 if ((shdr->Command != SMB2_SESSION_SETUP) &&
742 (shdr->Command != SMB2_NEGOTIATE))
743 return -EAGAIN;
744 /* else ok - we are setting up session */
745 }
746
747 if (ses->status == CifsExiting) {
748 if (shdr->Command != SMB2_LOGOFF)
749 return -EAGAIN;
750 /* else ok - we are shutting down the session */
751 }
752
753 *mid = smb2_mid_entry_alloc(shdr, server);
754 if (*mid == NULL)
755 return -ENOMEM;
756 spin_lock(&GlobalMid_Lock);
757 list_add_tail(&(*mid)->qhead, &server->pending_mid_q);
758 spin_unlock(&GlobalMid_Lock);
759
760 return 0;
761 }
762
763 int
smb2_check_receive(struct mid_q_entry * mid,struct TCP_Server_Info * server,bool log_error)764 smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
765 bool log_error)
766 {
767 unsigned int len = mid->resp_buf_size;
768 struct kvec iov[1];
769 struct smb_rqst rqst = { .rq_iov = iov,
770 .rq_nvec = 1 };
771
772 iov[0].iov_base = (char *)mid->resp_buf;
773 iov[0].iov_len = len;
774
775 dump_smb(mid->resp_buf, min_t(u32, 80, len));
776 /* convert the length into a more usable form */
777 if (len > 24 && server->sign && !mid->decrypted) {
778 int rc;
779
780 rc = smb2_verify_signature(&rqst, server);
781 if (rc)
782 cifs_server_dbg(VFS, "SMB signature verification returned error = %d\n",
783 rc);
784 }
785
786 return map_smb2_to_linux_error(mid->resp_buf, log_error);
787 }
788
789 struct mid_q_entry *
smb2_setup_request(struct cifs_ses * ses,struct TCP_Server_Info * server,struct smb_rqst * rqst)790 smb2_setup_request(struct cifs_ses *ses, struct TCP_Server_Info *server,
791 struct smb_rqst *rqst)
792 {
793 int rc;
794 struct smb2_sync_hdr *shdr =
795 (struct smb2_sync_hdr *)rqst->rq_iov[0].iov_base;
796 struct mid_q_entry *mid;
797
798 smb2_seq_num_into_buf(server, shdr);
799
800 rc = smb2_get_mid_entry(ses, server, shdr, &mid);
801 if (rc) {
802 revert_current_mid_from_hdr(server, shdr);
803 return ERR_PTR(rc);
804 }
805
806 rc = smb2_sign_rqst(rqst, server);
807 if (rc) {
808 revert_current_mid_from_hdr(server, shdr);
809 cifs_delete_mid(mid);
810 return ERR_PTR(rc);
811 }
812
813 return mid;
814 }
815
816 struct mid_q_entry *
smb2_setup_async_request(struct TCP_Server_Info * server,struct smb_rqst * rqst)817 smb2_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
818 {
819 int rc;
820 struct smb2_sync_hdr *shdr =
821 (struct smb2_sync_hdr *)rqst->rq_iov[0].iov_base;
822 struct mid_q_entry *mid;
823
824 if (server->tcpStatus == CifsNeedNegotiate &&
825 shdr->Command != SMB2_NEGOTIATE)
826 return ERR_PTR(-EAGAIN);
827
828 smb2_seq_num_into_buf(server, shdr);
829
830 mid = smb2_mid_entry_alloc(shdr, server);
831 if (mid == NULL) {
832 revert_current_mid_from_hdr(server, shdr);
833 return ERR_PTR(-ENOMEM);
834 }
835
836 rc = smb2_sign_rqst(rqst, server);
837 if (rc) {
838 revert_current_mid_from_hdr(server, shdr);
839 DeleteMidQEntry(mid);
840 return ERR_PTR(rc);
841 }
842
843 return mid;
844 }
845
846 int
smb3_crypto_aead_allocate(struct TCP_Server_Info * server)847 smb3_crypto_aead_allocate(struct TCP_Server_Info *server)
848 {
849 struct crypto_aead *tfm;
850
851 if (!server->secmech.ccmaesencrypt) {
852 if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
853 (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
854 tfm = crypto_alloc_aead("gcm(aes)", 0, 0);
855 else
856 tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
857 if (IS_ERR(tfm)) {
858 cifs_server_dbg(VFS, "%s: Failed alloc encrypt aead\n",
859 __func__);
860 return PTR_ERR(tfm);
861 }
862 server->secmech.ccmaesencrypt = tfm;
863 }
864
865 if (!server->secmech.ccmaesdecrypt) {
866 if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
867 (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
868 tfm = crypto_alloc_aead("gcm(aes)", 0, 0);
869 else
870 tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
871 if (IS_ERR(tfm)) {
872 crypto_free_aead(server->secmech.ccmaesencrypt);
873 server->secmech.ccmaesencrypt = NULL;
874 cifs_server_dbg(VFS, "%s: Failed to alloc decrypt aead\n",
875 __func__);
876 return PTR_ERR(tfm);
877 }
878 server->secmech.ccmaesdecrypt = tfm;
879 }
880
881 return 0;
882 }
883
