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1/*
2 * fs/cifs/cifsencrypt.c
3 *
4 * Encryption and hashing operations relating to NTLM, NTLMv2. See MS-NLMP
5 * for more detailed information
6 *
7 * Copyright (C) International Business Machines Corp., 2005,2013
8 * Author(s): Steve French (sfrench@us.ibm.com)
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/slab.h>
27#include "cifspdu.h"
28#include "cifsglob.h"
29#include "cifs_debug.h"
30#include "cifs_unicode.h"
31#include "cifsproto.h"
32#include "ntlmssp.h"
33#include <linux/ctype.h>
34#include <linux/random.h>
35#include <linux/highmem.h>
36#include <crypto/skcipher.h>
37
38static int
39cifs_crypto_shash_md5_allocate(struct TCP_Server_Info *server)
40{
41 int rc;
42 unsigned int size;
43
44 if (server->secmech.sdescmd5 != NULL)
45 return 0; /* already allocated */
46
47 server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
48 if (IS_ERR(server->secmech.md5)) {
49 cifs_dbg(VFS, "could not allocate crypto md5\n");
50 rc = PTR_ERR(server->secmech.md5);
51 server->secmech.md5 = NULL;
52 return rc;
53 }
54
55 size = sizeof(struct shash_desc) +
56 crypto_shash_descsize(server->secmech.md5);
57 server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
58 if (!server->secmech.sdescmd5) {
59 crypto_free_shash(server->secmech.md5);
60 server->secmech.md5 = NULL;
61 return -ENOMEM;
62 }
63 server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
64 server->secmech.sdescmd5->shash.flags = 0x0;
65
66 return 0;
67}
68
69/*
70 * Calculate and return the CIFS signature based on the mac key and SMB PDU.
71 * The 16 byte signature must be allocated by the caller. Note we only use the
72 * 1st eight bytes and that the smb header signature field on input contains
73 * the sequence number before this function is called. Also, this function
74 * should be called with the server->srv_mutex held.
75 */
76static int cifs_calc_signature(struct smb_rqst *rqst,
77 struct TCP_Server_Info *server, char *signature)
78{
79 int i;
80 int rc;
81 struct kvec *iov = rqst->rq_iov;
82 int n_vec = rqst->rq_nvec;
83
84 if (iov == NULL || signature == NULL || server == NULL)
85 return -EINVAL;
86
87 if (!server->secmech.sdescmd5) {
88 rc = cifs_crypto_shash_md5_allocate(server);
89 if (rc) {
90 cifs_dbg(VFS, "%s: Can't alloc md5 crypto\n", __func__);
91 return -1;
92 }
93 }
94
95 rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
96 if (rc) {
97 cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
98 return rc;
99 }
100
101 rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
102 server->session_key.response, server->session_key.len);
103 if (rc) {
104 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
105 return rc;
106 }
107
108 for (i = 0; i < n_vec; i++) {
109 if (iov[i].iov_len == 0)
110 continue;
111 if (iov[i].iov_base == NULL) {
112 cifs_dbg(VFS, "null iovec entry\n");
113 return -EIO;
114 }
115 /* The first entry includes a length field (which does not get
116 signed that occupies the first 4 bytes before the header */
117 if (i == 0) {
118 if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
119 break; /* nothing to sign or corrupt header */
120 rc =
121 crypto_shash_update(&server->secmech.sdescmd5->shash,
122 iov[i].iov_base + 4, iov[i].iov_len - 4);
123 } else {
124 rc =
125 crypto_shash_update(&server->secmech.sdescmd5->shash,
126 iov[i].iov_base, iov[i].iov_len);
127 }
128 if (rc) {
129 cifs_dbg(VFS, "%s: Could not update with payload\n",
130 __func__);
131 return rc;
132 }
133 }
134
135 /* now hash over the rq_pages array */
136 for (i = 0; i < rqst->rq_npages; i++) {
137 struct kvec p_iov;
138
139 cifs_rqst_page_to_kvec(rqst, i, &p_iov);
140 crypto_shash_update(&server->secmech.sdescmd5->shash,
141 p_iov.iov_base, p_iov.iov_len);
142 kunmap(rqst->rq_pages[i]);
143 }
144
145 rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
146 if (rc)
147 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
148
149 return rc;
150}
151
152/* must be called with server->srv_mutex held */
153int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
154 __u32 *pexpected_response_sequence_number)
155{
156 int rc = 0;
157 char smb_signature[20];
158 struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
159
160 if ((cifs_pdu == NULL) || (server == NULL))
161 return -EINVAL;
162
163 if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
164 server->tcpStatus == CifsNeedNegotiate)
165 return rc;
166
167 if (!server->session_estab) {
168 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
169 return rc;
170 }
171
172 cifs_pdu->Signature.Sequence.SequenceNumber =
173 cpu_to_le32(server->sequence_number);
174 cifs_pdu->Signature.Sequence.Reserved = 0;
175
176 *pexpected_response_sequence_number = ++server->sequence_number;
177 ++server->sequence_number;
178
179 rc = cifs_calc_signature(rqst, server, smb_signature);
180 if (rc)
181 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
182 else
183 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
184
185 return rc;
186}
187
188int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
189 __u32 *pexpected_response_sequence)
190{
191 struct smb_rqst rqst = { .rq_iov = iov,
192 .rq_nvec = n_vec };
193
194 return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
195}
196
197/* must be called with server->srv_mutex held */
198int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
199 __u32 *pexpected_response_sequence_number)
200{
201 struct kvec iov;
202
203 iov.iov_base = cifs_pdu;
204 iov.iov_len = be32_to_cpu(cifs_pdu->smb_buf_length) + 4;
205
206 return cifs_sign_smbv(&iov, 1, server,
207 pexpected_response_sequence_number);
208}
209
210int cifs_verify_signature(struct smb_rqst *rqst,
211 struct TCP_Server_Info *server,
212 __u32 expected_sequence_number)
213{
214 unsigned int rc;
215 char server_response_sig[8];
216 char what_we_think_sig_should_be[20];
217 struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
218
219 if (cifs_pdu == NULL || server == NULL)
220 return -EINVAL;
221
222 if (!server->session_estab)
223 return 0;
224
225 if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
226 struct smb_com_lock_req *pSMB =
227 (struct smb_com_lock_req *)cifs_pdu;
228 if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
229 return 0;
230 }
231
232 /* BB what if signatures are supposed to be on for session but
233 server does not send one? BB */
234
235 /* Do not need to verify session setups with signature "BSRSPYL " */
236 if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
237 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
238 cifs_pdu->Command);
239
240 /* save off the origiginal signature so we can modify the smb and check
241 its signature against what the server sent */
242 memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
243
244 cifs_pdu->Signature.Sequence.SequenceNumber =
245 cpu_to_le32(expected_sequence_number);
246 cifs_pdu->Signature.Sequence.Reserved = 0;
247
248 mutex_lock(&server->srv_mutex);
249 rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
250 mutex_unlock(&server->srv_mutex);
251
252 if (rc)
253 return rc;
254
255/* cifs_dump_mem("what we think it should be: ",
256 what_we_think_sig_should_be, 16); */
257
258 if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
259 return -EACCES;
260 else
261 return 0;
262
263}
264
265/* first calculate 24 bytes ntlm response and then 16 byte session key */
266int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
267{
268 int rc = 0;
269 unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
270 char temp_key[CIFS_SESS_KEY_SIZE];
271
272 if (!ses)
273 return -EINVAL;
274
275 ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
276 if (!ses->auth_key.response)
277 return -ENOMEM;
278
279 ses->auth_key.len = temp_len;
280
281 rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
282 ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
283 if (rc) {
284 cifs_dbg(FYI, "%s Can't generate NTLM response, error: %d\n",
285 __func__, rc);
286 return rc;
287 }
288
289 rc = E_md4hash(ses->password, temp_key, nls_cp);
290 if (rc) {
291 cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
292 __func__, rc);
293 return rc;
294 }
295
296 rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
297 if (rc)
298 cifs_dbg(FYI, "%s Can't generate NTLM session key, error: %d\n",
299 __func__, rc);
300
301 return rc;
302}
303
304#ifdef CONFIG_CIFS_WEAK_PW_HASH
305int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
306 char *lnm_session_key)
307{
308 int i;
309 int rc;
310 char password_with_pad[CIFS_ENCPWD_SIZE];
311
312 memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
313 if (password)
314 strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
315
316 if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
317 memcpy(lnm_session_key, password_with_pad,
318 CIFS_ENCPWD_SIZE);
319 return 0;
320 }
321
322 /* calculate old style session key */
323 /* calling toupper is less broken than repeatedly
324 calling nls_toupper would be since that will never
325 work for UTF8, but neither handles multibyte code pages
326 but the only alternative would be converting to UCS-16 (Unicode)
327 (using a routine something like UniStrupr) then
328 uppercasing and then converting back from Unicode - which
329 would only worth doing it if we knew it were utf8. Basically
330 utf8 and other multibyte codepages each need their own strupper
331 function since a byte at a time will ont work. */
332
333 for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
334 password_with_pad[i] = toupper(password_with_pad[i]);
335
336 rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
337
338 return rc;
339}
340#endif /* CIFS_WEAK_PW_HASH */
341
342/* Build a proper attribute value/target info pairs blob.
343 * Fill in netbios and dns domain name and workstation name
344 * and client time (total five av pairs and + one end of fields indicator.
345 * Allocate domain name which gets freed when session struct is deallocated.
346 */
347static int
348build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
349{
350 unsigned int dlen;
351 unsigned int size = 2 * sizeof(struct ntlmssp2_name);
352 char *defdmname = "WORKGROUP";
353 unsigned char *blobptr;
354 struct ntlmssp2_name *attrptr;
355
356 if (!ses->domainName) {
357 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
358 if (!ses->domainName)
359 return -ENOMEM;
360 }
361
362 dlen = strlen(ses->domainName);
363
364 /*
365 * The length of this blob is two times the size of a
366 * structure (av pair) which holds name/size
367 * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
368 * unicode length of a netbios domain name
369 */
370 ses->auth_key.len = size + 2 * dlen;
371 ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
372 if (!ses->auth_key.response) {
373 ses->auth_key.len = 0;
374 return -ENOMEM;
375 }
376
377 blobptr = ses->auth_key.response;
378 attrptr = (struct ntlmssp2_name *) blobptr;
379
380 /*
381 * As defined in MS-NTLM 3.3.2, just this av pair field
382 * is sufficient as part of the temp
383 */
384 attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
385 attrptr->length = cpu_to_le16(2 * dlen);
386 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
387 cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
388
389 return 0;
390}
391
392/* Server has provided av pairs/target info in the type 2 challenge
393 * packet and we have plucked it and stored within smb session.
394 * We parse that blob here to find netbios domain name to be used
395 * as part of ntlmv2 authentication (in Target String), if not already
396 * specified on the command line.
397 * If this function returns without any error but without fetching
398 * domain name, authentication may fail against some server but
399 * may not fail against other (those who are not very particular
400 * about target string i.e. for some, just user name might suffice.
401 */
402static int
403find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
404{
405 unsigned int attrsize;
406 unsigned int type;
407 unsigned int onesize = sizeof(struct ntlmssp2_name);
408 unsigned char *blobptr;
409 unsigned char *blobend;
410 struct ntlmssp2_name *attrptr;
411
412 if (!ses->auth_key.len || !ses->auth_key.response)
413 return 0;
414
415 blobptr = ses->auth_key.response;
416 blobend = blobptr + ses->auth_key.len;
417
418 while (blobptr + onesize < blobend) {
419 attrptr = (struct ntlmssp2_name *) blobptr;
420 type = le16_to_cpu(attrptr->type);
421 if (type == NTLMSSP_AV_EOL)
422 break;
423 blobptr += 2; /* advance attr type */
424 attrsize = le16_to_cpu(attrptr->length);
425 blobptr += 2; /* advance attr size */
426 if (blobptr + attrsize > blobend)
427 break;
428 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
429 if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
430 break;
431 if (!ses->domainName) {
432 ses->domainName =
433 kmalloc(attrsize + 1, GFP_KERNEL);
434 if (!ses->domainName)
435 return -ENOMEM;
436 cifs_from_utf16(ses->domainName,
437 (__le16 *)blobptr, attrsize, attrsize,
438 nls_cp, NO_MAP_UNI_RSVD);
439 break;
440 }
441 }
442 blobptr += attrsize; /* advance attr value */
443 }
444
445 return 0;
446}
447
448/* Server has provided av pairs/target info in the type 2 challenge
449 * packet and we have plucked it and stored within smb session.
450 * We parse that blob here to find the server given timestamp
451 * as part of ntlmv2 authentication (or local current time as
452 * default in case of failure)
453 */
454static __le64
455find_timestamp(struct cifs_ses *ses)
456{
457 unsigned int attrsize;
458 unsigned int type;
459 unsigned int onesize = sizeof(struct ntlmssp2_name);
460 unsigned char *blobptr;
461 unsigned char *blobend;
462 struct ntlmssp2_name *attrptr;
463
464 if (!ses->auth_key.len || !ses->auth_key.response)
465 return 0;
466
467 blobptr = ses->auth_key.response;
468 blobend = blobptr + ses->auth_key.len;
469
470 while (blobptr + onesize < blobend) {
471 attrptr = (struct ntlmssp2_name *) blobptr;
472 type = le16_to_cpu(attrptr->type);
473 if (type == NTLMSSP_AV_EOL)
474 break;
475 blobptr += 2; /* advance attr type */
476 attrsize = le16_to_cpu(attrptr->length);
477 blobptr += 2; /* advance attr size */
478 if (blobptr + attrsize > blobend)
479 break;
480 if (type == NTLMSSP_AV_TIMESTAMP) {
481 if (attrsize == sizeof(u64))
482 return *((__le64 *)blobptr);
483 }
484 blobptr += attrsize; /* advance attr value */
485 }
486
487 return cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
488}
489
490static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
491 const struct nls_table *nls_cp)
492{
493 int rc = 0;
494 int len;
495 char nt_hash[CIFS_NTHASH_SIZE];
496 __le16 *user;
497 wchar_t *domain;
498 wchar_t *server;
499
500 if (!ses->server->secmech.sdeschmacmd5) {
501 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
502 return -1;
503 }
504
505 /* calculate md4 hash of password */
506 E_md4hash(ses->password, nt_hash, nls_cp);
507
508 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
509 CIFS_NTHASH_SIZE);
510 if (rc) {
511 cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
512 return rc;
513 }
514
515 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
516 if (rc) {
517 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
518 return rc;
519 }
520
521 /* convert ses->user_name to unicode */
522 len = ses->user_name ? strlen(ses->user_name) : 0;
523 user = kmalloc(2 + (len * 2), GFP_KERNEL);
524 if (user == NULL) {
525 rc = -ENOMEM;
526 return rc;
527 }
528
529 if (len) {
530 len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
531 UniStrupr(user);
532 } else {
533 memset(user, '\0', 2);
534 }
535
536 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
537 (char *)user, 2 * len);
538 kfree(user);
539 if (rc) {
540 cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
541 return rc;
542 }
543
544 /* convert ses->domainName to unicode and uppercase */
545 if (ses->domainName) {
546 len = strlen(ses->domainName);
547
548 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
549 if (domain == NULL) {
550 rc = -ENOMEM;
551 return rc;
552 }
553 len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
554 nls_cp);
555 rc =
556 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
557 (char *)domain, 2 * len);
558 kfree(domain);
559 if (rc) {
560 cifs_dbg(VFS, "%s: Could not update with domain\n",
561 __func__);
562 return rc;
563 }
564 } else {
565 /* We use ses->serverName if no domain name available */
566 len = strlen(ses->serverName);
567
568 server = kmalloc(2 + (len * 2), GFP_KERNEL);
569 if (server == NULL) {
570 rc = -ENOMEM;
571 return rc;
572 }
573 len = cifs_strtoUTF16((__le16 *)server, ses->serverName, len,
574 nls_cp);
575 rc =
576 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
577 (char *)server, 2 * len);
578 kfree(server);
579 if (rc) {
580 cifs_dbg(VFS, "%s: Could not update with server\n",
581 __func__);
582 return rc;
583 }
584 }
585
586 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
587 ntlmv2_hash);
588 if (rc)
589 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
590
591 return rc;
592}
593
594static int
595CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
596{
597 int rc;
598 struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
599 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
600 unsigned int hash_len;
601
602 /* The MD5 hash starts at challenge_key.key */
603 hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
604 offsetof(struct ntlmv2_resp, challenge.key[0]));
605
606 if (!ses->server->secmech.sdeschmacmd5) {
607 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
608 return -1;
609 }
610
611 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
612 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
613 if (rc) {
614 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
615 __func__);
616 return rc;
617 }
618
619 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
620 if (rc) {
621 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
622 return rc;
623 }
624
625 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
626 memcpy(ntlmv2->challenge.key,
627 ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
628 else
629 memcpy(ntlmv2->challenge.key,
630 ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
631 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
632 ntlmv2->challenge.key, hash_len);
633 if (rc) {
634 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
635 return rc;
636 }
637
638 /* Note that the MD5 digest over writes anon.challenge_key.key */
639 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
640 ntlmv2->ntlmv2_hash);
641 if (rc)
642 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
643
644 return rc;
645}
646
647static int crypto_hmacmd5_alloc(struct TCP_Server_Info *server)
648{
649 int rc;
650 unsigned int size;
651
652 /* check if already allocated */
653 if (server->secmech.sdeschmacmd5)
654 return 0;
655
656 server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
657 if (IS_ERR(server->secmech.hmacmd5)) {
658 cifs_dbg(VFS, "could not allocate crypto hmacmd5\n");
659 rc = PTR_ERR(server->secmech.hmacmd5);
660 server->secmech.hmacmd5 = NULL;
661 return rc;
662 }
663
664 size = sizeof(struct shash_desc) +
665 crypto_shash_descsize(server->secmech.hmacmd5);
666 server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
667 if (!server->secmech.sdeschmacmd5) {
668 crypto_free_shash(server->secmech.hmacmd5);
669 server->secmech.hmacmd5 = NULL;
670 return -ENOMEM;
671 }
672 server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
673 server->secmech.sdeschmacmd5->shash.flags = 0x0;
674
675 return 0;
676}
677
678int
679setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
680{
681 int rc;
682 int baselen;
683 unsigned int tilen;
684 struct ntlmv2_resp *ntlmv2;
685 char ntlmv2_hash[16];
686 unsigned char *tiblob = NULL; /* target info blob */
687 __le64 rsp_timestamp;
688
689 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
690 if (!ses->domainName) {
691 rc = find_domain_name(ses, nls_cp);
692 if (rc) {
693 cifs_dbg(VFS, "error %d finding domain name\n",
694 rc);
695 goto setup_ntlmv2_rsp_ret;
696 }
697 }
698 } else {
699 rc = build_avpair_blob(ses, nls_cp);
700 if (rc) {
701 cifs_dbg(VFS, "error %d building av pair blob\n", rc);
702 goto setup_ntlmv2_rsp_ret;
703 }
704 }
705
706 /* Must be within 5 minutes of the server (or in range +/-2h
707 * in case of Mac OS X), so simply carry over server timestamp
708 * (as Windows 7 does)
709 */
710 rsp_timestamp = find_timestamp(ses);
711
712 baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
713 tilen = ses->auth_key.len;
714 tiblob = ses->auth_key.response;
715
716 ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
717 if (!ses->auth_key.response) {
718 rc = -ENOMEM;
719 ses->auth_key.len = 0;
720 goto setup_ntlmv2_rsp_ret;
721 }
722 ses->auth_key.len += baselen;
723
724 ntlmv2 = (struct ntlmv2_resp *)
725 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
726 ntlmv2->blob_signature = cpu_to_le32(0x00000101);
727 ntlmv2->reserved = 0;
728 ntlmv2->time = rsp_timestamp;
729
730 get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
731 ntlmv2->reserved2 = 0;
732
733 memcpy(ses->auth_key.response + baselen, tiblob, tilen);
734
735 rc = crypto_hmacmd5_alloc(ses->server);
736 if (rc) {
737 cifs_dbg(VFS, "could not crypto alloc hmacmd5 rc %d\n", rc);
738 goto setup_ntlmv2_rsp_ret;
739 }
740
741 /* calculate ntlmv2_hash */
742 rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
743 if (rc) {
744 cifs_dbg(VFS, "could not get v2 hash rc %d\n", rc);
745 goto setup_ntlmv2_rsp_ret;
746 }
747
748 /* calculate first part of the client response (CR1) */
749 rc = CalcNTLMv2_response(ses, ntlmv2_hash);
750 if (rc) {
751 cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
752 goto setup_ntlmv2_rsp_ret;
753 }
754
755 /* now calculate the session key for NTLMv2 */
756 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
757 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
758 if (rc) {
759 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
760 __func__);
761 goto setup_ntlmv2_rsp_ret;
762 }
763
764 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
765 if (rc) {
766 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
767 goto setup_ntlmv2_rsp_ret;
768 }
769
770 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
771 ntlmv2->ntlmv2_hash,
772 CIFS_HMAC_MD5_HASH_SIZE);
773 if (rc) {
774 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
775 goto setup_ntlmv2_rsp_ret;
776 }
777
778 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
779 ses->auth_key.response);
780 if (rc)
781 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
782
783setup_ntlmv2_rsp_ret:
784 kfree(tiblob);
785
786 return rc;
787}
788
789int
790calc_seckey(struct cifs_ses *ses)
791{
792 int rc;
793 struct crypto_skcipher *tfm_arc4;
794 struct scatterlist sgin, sgout;
795 struct skcipher_request *req;
796 unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
797
798 get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
799
800 tfm_arc4 = crypto_alloc_skcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
801 if (IS_ERR(tfm_arc4)) {
802 rc = PTR_ERR(tfm_arc4);
803 cifs_dbg(VFS, "could not allocate crypto API arc4\n");
804 return rc;
805 }
806
807 rc = crypto_skcipher_setkey(tfm_arc4, ses->auth_key.response,
808 CIFS_SESS_KEY_SIZE);
809 if (rc) {
810 cifs_dbg(VFS, "%s: Could not set response as a key\n",
811 __func__);
812 goto out_free_cipher;
813 }
814
815 req = skcipher_request_alloc(tfm_arc4, GFP_KERNEL);
816 if (!req) {
817 rc = -ENOMEM;
818 cifs_dbg(VFS, "could not allocate crypto API arc4 request\n");
819 goto out_free_cipher;
820 }
821
822 sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
823 sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
824
825 skcipher_request_set_callback(req, 0, NULL, NULL);
826 skcipher_request_set_crypt(req, &sgin, &sgout, CIFS_CPHTXT_SIZE, NULL);
827
828 rc = crypto_skcipher_encrypt(req);
829 skcipher_request_free(req);
830 if (rc) {
831 cifs_dbg(VFS, "could not encrypt session key rc: %d\n", rc);
832 goto out_free_cipher;
833 }
834
835 /* make secondary_key/nonce as session key */
836 memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
837 /* and make len as that of session key only */
838 ses->auth_key.len = CIFS_SESS_KEY_SIZE;
839
840out_free_cipher:
841 crypto_free_skcipher(tfm_arc4);
842
843 return rc;
844}
845
846void
847cifs_crypto_shash_release(struct TCP_Server_Info *server)
848{
849 if (server->secmech.cmacaes) {
850 crypto_free_shash(server->secmech.cmacaes);
851 server->secmech.cmacaes = NULL;
852 }
853
854 if (server->secmech.hmacsha256) {
855 crypto_free_shash(server->secmech.hmacsha256);
856 server->secmech.hmacsha256 = NULL;
857 }
858
859 if (server->secmech.md5) {
860 crypto_free_shash(server->secmech.md5);
861 server->secmech.md5 = NULL;
862 }
863
864 if (server->secmech.hmacmd5) {
865 crypto_free_shash(server->secmech.hmacmd5);
866 server->secmech.hmacmd5 = NULL;
867 }
868
869 kfree(server->secmech.sdesccmacaes);
870 server->secmech.sdesccmacaes = NULL;
871 kfree(server->secmech.sdeschmacsha256);
872 server->secmech.sdeschmacsha256 = NULL;
873 kfree(server->secmech.sdeschmacmd5);
874 server->secmech.sdeschmacmd5 = NULL;
875 kfree(server->secmech.sdescmd5);
876 server->secmech.sdescmd5 = NULL;
877}
1/*
2 * fs/cifs/cifsencrypt.c
3 *
4 * Encryption and hashing operations relating to NTLM, NTLMv2. See MS-NLMP
5 * for more detailed information
6 *
7 * Copyright (C) International Business Machines Corp., 2005,2013
8 * Author(s): Steve French (sfrench@us.ibm.com)
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/slab.h>
27#include "cifspdu.h"
28#include "cifsglob.h"
29#include "cifs_debug.h"
30#include "cifs_unicode.h"
31#include "cifsproto.h"
32#include "ntlmssp.h"
33#include <linux/ctype.h>
34#include <linux/random.h>
35#include <linux/highmem.h>
36#include <linux/fips.h>
37#include <crypto/arc4.h>
38#include <crypto/aead.h>
39
40int __cifs_calc_signature(struct smb_rqst *rqst,
41 struct TCP_Server_Info *server, char *signature,
42 struct shash_desc *shash)
43{
44 int i;
45 int rc;
46 struct kvec *iov = rqst->rq_iov;
47 int n_vec = rqst->rq_nvec;
48 int is_smb2 = server->vals->header_preamble_size == 0;
49
50 /* iov[0] is actual data and not the rfc1002 length for SMB2+ */
51 if (is_smb2) {
52 if (iov[0].iov_len <= 4)
53 return -EIO;
54 i = 0;
55 } else {
56 if (n_vec < 2 || iov[0].iov_len != 4)
57 return -EIO;
58 i = 1; /* skip rfc1002 length */
59 }
60
61 for (; i < n_vec; i++) {
62 if (iov[i].iov_len == 0)
63 continue;
64 if (iov[i].iov_base == NULL) {
65 cifs_dbg(VFS, "null iovec entry\n");
66 return -EIO;
67 }
68
69 rc = crypto_shash_update(shash,
70 iov[i].iov_base, iov[i].iov_len);
71 if (rc) {
72 cifs_dbg(VFS, "%s: Could not update with payload\n",
73 __func__);
74 return rc;
75 }
76 }
77
78 /* now hash over the rq_pages array */
79 for (i = 0; i < rqst->rq_npages; i++) {
80 void *kaddr;
81 unsigned int len, offset;
82
83 rqst_page_get_length(rqst, i, &len, &offset);
84
85 kaddr = (char *) kmap(rqst->rq_pages[i]) + offset;
86
87 rc = crypto_shash_update(shash, kaddr, len);
88 if (rc) {
89 cifs_dbg(VFS, "%s: Could not update with payload\n",
90 __func__);
91 kunmap(rqst->rq_pages[i]);
92 return rc;
93 }
94
95 kunmap(rqst->rq_pages[i]);
96 }
97
98 rc = crypto_shash_final(shash, signature);
99 if (rc)
100 cifs_dbg(VFS, "%s: Could not generate hash\n", __func__);
101
102 return rc;
103}
104
105/*
106 * Calculate and return the CIFS signature based on the mac key and SMB PDU.
107 * The 16 byte signature must be allocated by the caller. Note we only use the
108 * 1st eight bytes and that the smb header signature field on input contains
109 * the sequence number before this function is called. Also, this function
110 * should be called with the server->srv_mutex held.
111 */
112static int cifs_calc_signature(struct smb_rqst *rqst,
113 struct TCP_Server_Info *server, char *signature)
114{
115 int rc;
116
117 if (!rqst->rq_iov || !signature || !server)
118 return -EINVAL;
119
120 rc = cifs_alloc_hash("md5", &server->secmech.md5,
121 &server->secmech.sdescmd5);
122 if (rc)
123 return -1;
124
125 rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
126 if (rc) {
127 cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
128 return rc;
129 }
130
131 rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
132 server->session_key.response, server->session_key.len);
133 if (rc) {
134 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
135 return rc;
136 }
137
138 return __cifs_calc_signature(rqst, server, signature,
139 &server->secmech.sdescmd5->shash);
140}
141
142/* must be called with server->srv_mutex held */
143int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
144 __u32 *pexpected_response_sequence_number)
145{
146 int rc = 0;
147 char smb_signature[20];
148 struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
149
150 if (rqst->rq_iov[0].iov_len != 4 ||
151 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
152 return -EIO;
153
154 if ((cifs_pdu == NULL) || (server == NULL))
155 return -EINVAL;
156
157 if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
158 server->tcpStatus == CifsNeedNegotiate)
159 return rc;
160
161 if (!server->session_estab) {
162 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
163 return rc;
164 }
165
166 cifs_pdu->Signature.Sequence.SequenceNumber =
167 cpu_to_le32(server->sequence_number);
168 cifs_pdu->Signature.Sequence.Reserved = 0;
169
170 *pexpected_response_sequence_number = ++server->sequence_number;
171 ++server->sequence_number;
172
173 rc = cifs_calc_signature(rqst, server, smb_signature);
174 if (rc)
175 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
176 else
177 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
178
179 return rc;
180}
181
182int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
183 __u32 *pexpected_response_sequence)
184{
185 struct smb_rqst rqst = { .rq_iov = iov,
186 .rq_nvec = n_vec };
187
188 return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
189}
190
191/* must be called with server->srv_mutex held */
192int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
193 __u32 *pexpected_response_sequence_number)
194{
195 struct kvec iov[2];
196
197 iov[0].iov_base = cifs_pdu;
198 iov[0].iov_len = 4;
199 iov[1].iov_base = (char *)cifs_pdu + 4;
200 iov[1].iov_len = be32_to_cpu(cifs_pdu->smb_buf_length);
201
202 return cifs_sign_smbv(iov, 2, server,
203 pexpected_response_sequence_number);
204}
205
206int cifs_verify_signature(struct smb_rqst *rqst,
207 struct TCP_Server_Info *server,
208 __u32 expected_sequence_number)
209{
210 unsigned int rc;
211 char server_response_sig[8];
212 char what_we_think_sig_should_be[20];
213 struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
214
215 if (rqst->rq_iov[0].iov_len != 4 ||
216 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
217 return -EIO;
218
219 if (cifs_pdu == NULL || server == NULL)
220 return -EINVAL;
221
222 if (!server->session_estab)
223 return 0;
224
225 if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
226 struct smb_com_lock_req *pSMB =
227 (struct smb_com_lock_req *)cifs_pdu;
228 if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
229 return 0;
230 }
231
232 /* BB what if signatures are supposed to be on for session but
233 server does not send one? BB */
234
235 /* Do not need to verify session setups with signature "BSRSPYL " */
236 if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
237 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
238 cifs_pdu->Command);
239
240 /* save off the origiginal signature so we can modify the smb and check
241 its signature against what the server sent */
242 memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
243
244 cifs_pdu->Signature.Sequence.SequenceNumber =
245 cpu_to_le32(expected_sequence_number);
246 cifs_pdu->Signature.Sequence.Reserved = 0;
247
248 mutex_lock(&server->srv_mutex);
249 rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
250 mutex_unlock(&server->srv_mutex);
251
252 if (rc)
253 return rc;
254
255/* cifs_dump_mem("what we think it should be: ",
256 what_we_think_sig_should_be, 16); */
257
258 if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
259 return -EACCES;
260 else
261 return 0;
262
263}
264
265/* first calculate 24 bytes ntlm response and then 16 byte session key */
266int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
267{
268 int rc = 0;
269 unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
270 char temp_key[CIFS_SESS_KEY_SIZE];
271
272 if (!ses)
273 return -EINVAL;
274
275 ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
276 if (!ses->auth_key.response)
277 return -ENOMEM;
278
279 ses->auth_key.len = temp_len;
280
281 rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
282 ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
283 if (rc) {
284 cifs_dbg(FYI, "%s Can't generate NTLM response, error: %d\n",
285 __func__, rc);
286 return rc;
287 }
288
289 rc = E_md4hash(ses->password, temp_key, nls_cp);
290 if (rc) {
291 cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
292 __func__, rc);
293 return rc;
294 }
295
296 rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
297 if (rc)
298 cifs_dbg(FYI, "%s Can't generate NTLM session key, error: %d\n",
299 __func__, rc);
300
301 return rc;
302}
303
304#ifdef CONFIG_CIFS_WEAK_PW_HASH
305int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
306 char *lnm_session_key)
307{
308 int i, len;
309 int rc;
310 char password_with_pad[CIFS_ENCPWD_SIZE] = {0};
311
312 if (password) {
313 for (len = 0; len < CIFS_ENCPWD_SIZE; len++)
314 if (!password[len])
315 break;
316
317 memcpy(password_with_pad, password, len);
318 }
319
320 if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
321 memcpy(lnm_session_key, password_with_pad,
322 CIFS_ENCPWD_SIZE);
323 return 0;
324 }
325
326 /* calculate old style session key */
327 /* calling toupper is less broken than repeatedly
328 calling nls_toupper would be since that will never
329 work for UTF8, but neither handles multibyte code pages
330 but the only alternative would be converting to UCS-16 (Unicode)
331 (using a routine something like UniStrupr) then
332 uppercasing and then converting back from Unicode - which
333 would only worth doing it if we knew it were utf8. Basically
334 utf8 and other multibyte codepages each need their own strupper
335 function since a byte at a time will ont work. */
336
337 for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
338 password_with_pad[i] = toupper(password_with_pad[i]);
339
340 rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
341
342 return rc;
343}
344#endif /* CIFS_WEAK_PW_HASH */
345
346/* Build a proper attribute value/target info pairs blob.
347 * Fill in netbios and dns domain name and workstation name
348 * and client time (total five av pairs and + one end of fields indicator.
349 * Allocate domain name which gets freed when session struct is deallocated.
350 */
351static int
352build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
353{
354 unsigned int dlen;
355 unsigned int size = 2 * sizeof(struct ntlmssp2_name);
356 char *defdmname = "WORKGROUP";
357 unsigned char *blobptr;
358 struct ntlmssp2_name *attrptr;
359
360 if (!ses->domainName) {
361 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
362 if (!ses->domainName)
363 return -ENOMEM;
364 }
365
366 dlen = strlen(ses->domainName);
367
368 /*
369 * The length of this blob is two times the size of a
370 * structure (av pair) which holds name/size
371 * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
372 * unicode length of a netbios domain name
373 */
374 ses->auth_key.len = size + 2 * dlen;
375 ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
376 if (!ses->auth_key.response) {
377 ses->auth_key.len = 0;
378 return -ENOMEM;
379 }
380
381 blobptr = ses->auth_key.response;
382 attrptr = (struct ntlmssp2_name *) blobptr;
383
384 /*
385 * As defined in MS-NTLM 3.3.2, just this av pair field
386 * is sufficient as part of the temp
387 */
388 attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
389 attrptr->length = cpu_to_le16(2 * dlen);
390 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
391 cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
392
393 return 0;
394}
395
396/* Server has provided av pairs/target info in the type 2 challenge
397 * packet and we have plucked it and stored within smb session.
398 * We parse that blob here to find netbios domain name to be used
399 * as part of ntlmv2 authentication (in Target String), if not already
400 * specified on the command line.
401 * If this function returns without any error but without fetching
402 * domain name, authentication may fail against some server but
403 * may not fail against other (those who are not very particular
404 * about target string i.e. for some, just user name might suffice.
405 */
406static int
407find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
408{
409 unsigned int attrsize;
410 unsigned int type;
411 unsigned int onesize = sizeof(struct ntlmssp2_name);
412 unsigned char *blobptr;
413 unsigned char *blobend;
414 struct ntlmssp2_name *attrptr;
415
416 if (!ses->auth_key.len || !ses->auth_key.response)
417 return 0;
418
419 blobptr = ses->auth_key.response;
420 blobend = blobptr + ses->auth_key.len;
421
422 while (blobptr + onesize < blobend) {
423 attrptr = (struct ntlmssp2_name *) blobptr;
424 type = le16_to_cpu(attrptr->type);
425 if (type == NTLMSSP_AV_EOL)
426 break;
427 blobptr += 2; /* advance attr type */
428 attrsize = le16_to_cpu(attrptr->length);
429 blobptr += 2; /* advance attr size */
430 if (blobptr + attrsize > blobend)
431 break;
432 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
433 if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
434 break;
435 if (!ses->domainName) {
436 ses->domainName =
437 kmalloc(attrsize + 1, GFP_KERNEL);
438 if (!ses->domainName)
439 return -ENOMEM;
440 cifs_from_utf16(ses->domainName,
441 (__le16 *)blobptr, attrsize, attrsize,
442 nls_cp, NO_MAP_UNI_RSVD);
443 break;
444 }
445 }
446 blobptr += attrsize; /* advance attr value */
447 }
448
449 return 0;
450}
451
452/* Server has provided av pairs/target info in the type 2 challenge
453 * packet and we have plucked it and stored within smb session.
454 * We parse that blob here to find the server given timestamp
455 * as part of ntlmv2 authentication (or local current time as
456 * default in case of failure)
457 */
458static __le64
459find_timestamp(struct cifs_ses *ses)
460{
461 unsigned int attrsize;
462 unsigned int type;
463 unsigned int onesize = sizeof(struct ntlmssp2_name);
464 unsigned char *blobptr;
465 unsigned char *blobend;
466 struct ntlmssp2_name *attrptr;
467 struct timespec64 ts;
468
469 if (!ses->auth_key.len || !ses->auth_key.response)
470 return 0;
471
472 blobptr = ses->auth_key.response;
473 blobend = blobptr + ses->auth_key.len;
474
475 while (blobptr + onesize < blobend) {
476 attrptr = (struct ntlmssp2_name *) blobptr;
477 type = le16_to_cpu(attrptr->type);
478 if (type == NTLMSSP_AV_EOL)
479 break;
480 blobptr += 2; /* advance attr type */
481 attrsize = le16_to_cpu(attrptr->length);
482 blobptr += 2; /* advance attr size */
483 if (blobptr + attrsize > blobend)
484 break;
485 if (type == NTLMSSP_AV_TIMESTAMP) {
486 if (attrsize == sizeof(u64))
487 return *((__le64 *)blobptr);
488 }
489 blobptr += attrsize; /* advance attr value */
490 }
491
492 ktime_get_real_ts64(&ts);
493 return cpu_to_le64(cifs_UnixTimeToNT(ts));
494}
495
496static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
497 const struct nls_table *nls_cp)
498{
499 int rc = 0;
500 int len;
501 char nt_hash[CIFS_NTHASH_SIZE];
502 __le16 *user;
503 wchar_t *domain;
504 wchar_t *server;
505
506 if (!ses->server->secmech.sdeschmacmd5) {
507 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
508 return -1;
509 }
510
511 /* calculate md4 hash of password */
512 E_md4hash(ses->password, nt_hash, nls_cp);
513
514 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
515 CIFS_NTHASH_SIZE);
516 if (rc) {
517 cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
518 return rc;
519 }
520
521 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
522 if (rc) {
523 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
524 return rc;
525 }
526
527 /* convert ses->user_name to unicode */
528 len = ses->user_name ? strlen(ses->user_name) : 0;
529 user = kmalloc(2 + (len * 2), GFP_KERNEL);
530 if (user == NULL) {
531 rc = -ENOMEM;
532 return rc;
533 }
534
535 if (len) {
536 len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
537 UniStrupr(user);
538 } else {
539 memset(user, '\0', 2);
540 }
541
542 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
543 (char *)user, 2 * len);
544 kfree(user);
545 if (rc) {
546 cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
547 return rc;
548 }
549
550 /* convert ses->domainName to unicode and uppercase */
551 if (ses->domainName) {
552 len = strlen(ses->domainName);
553
554 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
555 if (domain == NULL) {
556 rc = -ENOMEM;
557 return rc;
558 }
559 len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
560 nls_cp);
561 rc =
562 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
563 (char *)domain, 2 * len);
564 kfree(domain);
565 if (rc) {
566 cifs_dbg(VFS, "%s: Could not update with domain\n",
567 __func__);
568 return rc;
569 }
570 } else {
571 /* We use ses->serverName if no domain name available */
572 len = strlen(ses->serverName);
573
574 server = kmalloc(2 + (len * 2), GFP_KERNEL);
575 if (server == NULL) {
576 rc = -ENOMEM;
577 return rc;
578 }
579 len = cifs_strtoUTF16((__le16 *)server, ses->serverName, len,
580 nls_cp);
581 rc =
582 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
583 (char *)server, 2 * len);
584 kfree(server);
585 if (rc) {
586 cifs_dbg(VFS, "%s: Could not update with server\n",
587 __func__);
588 return rc;
589 }
590 }
591
592 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
593 ntlmv2_hash);
594 if (rc)
595 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
596
597 return rc;
598}
599
600static int
601CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
602{
603 int rc;
604 struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
605 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
606 unsigned int hash_len;
607
608 /* The MD5 hash starts at challenge_key.key */
609 hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
610 offsetof(struct ntlmv2_resp, challenge.key[0]));
611
612 if (!ses->server->secmech.sdeschmacmd5) {
613 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
614 return -1;
615 }
616
617 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
618 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
619 if (rc) {
620 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
621 __func__);
622 return rc;
623 }
624
625 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
626 if (rc) {
627 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
628 return rc;
629 }
630
631 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
632 memcpy(ntlmv2->challenge.key,
633 ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
634 else
635 memcpy(ntlmv2->challenge.key,
636 ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
637 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
638 ntlmv2->challenge.key, hash_len);
639 if (rc) {
640 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
641 return rc;
642 }
643
644 /* Note that the MD5 digest over writes anon.challenge_key.key */
645 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
646 ntlmv2->ntlmv2_hash);
647 if (rc)
648 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
649
650 return rc;
651}
652
653int
654setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
655{
656 int rc;
657 int baselen;
658 unsigned int tilen;
659 struct ntlmv2_resp *ntlmv2;
660 char ntlmv2_hash[16];
661 unsigned char *tiblob = NULL; /* target info blob */
662 __le64 rsp_timestamp;
663
664 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
665 if (!ses->domainName) {
666 if (ses->domainAuto) {
667 rc = find_domain_name(ses, nls_cp);
668 if (rc) {
669 cifs_dbg(VFS, "error %d finding domain name\n",
670 rc);
671 goto setup_ntlmv2_rsp_ret;
672 }
673 } else {
674 ses->domainName = kstrdup("", GFP_KERNEL);
675 }
676 }
677 } else {
678 rc = build_avpair_blob(ses, nls_cp);
679 if (rc) {
680 cifs_dbg(VFS, "error %d building av pair blob\n", rc);
681 goto setup_ntlmv2_rsp_ret;
682 }
683 }
684
685 /* Must be within 5 minutes of the server (or in range +/-2h
686 * in case of Mac OS X), so simply carry over server timestamp
687 * (as Windows 7 does)
688 */
689 rsp_timestamp = find_timestamp(ses);
690
691 baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
692 tilen = ses->auth_key.len;
693 tiblob = ses->auth_key.response;
694
695 ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
696 if (!ses->auth_key.response) {
697 rc = -ENOMEM;
698 ses->auth_key.len = 0;
699 goto setup_ntlmv2_rsp_ret;
700 }
701 ses->auth_key.len += baselen;
702
703 ntlmv2 = (struct ntlmv2_resp *)
704 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
705 ntlmv2->blob_signature = cpu_to_le32(0x00000101);
706 ntlmv2->reserved = 0;
707 ntlmv2->time = rsp_timestamp;
708
709 get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
710 ntlmv2->reserved2 = 0;
711
712 memcpy(ses->auth_key.response + baselen, tiblob, tilen);
713
714 mutex_lock(&ses->server->srv_mutex);
715
716 rc = cifs_alloc_hash("hmac(md5)",
717 &ses->server->secmech.hmacmd5,
718 &ses->server->secmech.sdeschmacmd5);
719 if (rc) {
720 goto unlock;
721 }
722
723 /* calculate ntlmv2_hash */
724 rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
725 if (rc) {
726 cifs_dbg(VFS, "Could not get v2 hash rc %d\n", rc);
727 goto unlock;
728 }
729
730 /* calculate first part of the client response (CR1) */
731 rc = CalcNTLMv2_response(ses, ntlmv2_hash);
732 if (rc) {
733 cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
734 goto unlock;
735 }
736
737 /* now calculate the session key for NTLMv2 */
738 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
739 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
740 if (rc) {
741 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
742 __func__);
743 goto unlock;
744 }
745
746 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
747 if (rc) {
748 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
749 goto unlock;
750 }
751
752 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
753 ntlmv2->ntlmv2_hash,
754 CIFS_HMAC_MD5_HASH_SIZE);
755 if (rc) {
756 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
757 goto unlock;
758 }
759
760 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
761 ses->auth_key.response);
762 if (rc)
763 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
764
765unlock:
766 mutex_unlock(&ses->server->srv_mutex);
767setup_ntlmv2_rsp_ret:
768 kfree(tiblob);
769
770 return rc;
771}
772
773int
774calc_seckey(struct cifs_ses *ses)
775{
776 unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
777 struct arc4_ctx *ctx_arc4;
778
779 if (fips_enabled)
780 return -ENODEV;
781
782 get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
783
784 ctx_arc4 = kmalloc(sizeof(*ctx_arc4), GFP_KERNEL);
785 if (!ctx_arc4) {
786 cifs_dbg(VFS, "Could not allocate arc4 context\n");
787 return -ENOMEM;
788 }
789
790 arc4_setkey(ctx_arc4, ses->auth_key.response, CIFS_SESS_KEY_SIZE);
791 arc4_crypt(ctx_arc4, ses->ntlmssp->ciphertext, sec_key,
792 CIFS_CPHTXT_SIZE);
793
794 /* make secondary_key/nonce as session key */
795 memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
796 /* and make len as that of session key only */
797 ses->auth_key.len = CIFS_SESS_KEY_SIZE;
798
799 memzero_explicit(sec_key, CIFS_SESS_KEY_SIZE);
800 kfree_sensitive(ctx_arc4);
801 return 0;
802}
803
804void
805cifs_crypto_secmech_release(struct TCP_Server_Info *server)
806{
807 if (server->secmech.cmacaes) {
808 crypto_free_shash(server->secmech.cmacaes);
809 server->secmech.cmacaes = NULL;
810 }
811
812 if (server->secmech.hmacsha256) {
813 crypto_free_shash(server->secmech.hmacsha256);
814 server->secmech.hmacsha256 = NULL;
815 }
816
817 if (server->secmech.md5) {
818 crypto_free_shash(server->secmech.md5);
819 server->secmech.md5 = NULL;
820 }
821
822 if (server->secmech.sha512) {
823 crypto_free_shash(server->secmech.sha512);
824 server->secmech.sha512 = NULL;
825 }
826
827 if (server->secmech.hmacmd5) {
828 crypto_free_shash(server->secmech.hmacmd5);
829 server->secmech.hmacmd5 = NULL;
830 }
831
832 if (server->secmech.ccmaesencrypt) {
833 crypto_free_aead(server->secmech.ccmaesencrypt);
834 server->secmech.ccmaesencrypt = NULL;
835 }
836
837 if (server->secmech.ccmaesdecrypt) {
838 crypto_free_aead(server->secmech.ccmaesdecrypt);
839 server->secmech.ccmaesdecrypt = NULL;
840 }
841
842 kfree(server->secmech.sdesccmacaes);
843 server->secmech.sdesccmacaes = NULL;
844 kfree(server->secmech.sdeschmacsha256);
845 server->secmech.sdeschmacsha256 = NULL;
846 kfree(server->secmech.sdeschmacmd5);
847 server->secmech.sdeschmacmd5 = NULL;
848 kfree(server->secmech.sdescmd5);
849 server->secmech.sdescmd5 = NULL;
850 kfree(server->secmech.sdescsha512);
851 server->secmech.sdescsha512 = NULL;
852}