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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#include <crypto/aead.h>
38
39int __cifs_calc_signature(struct smb_rqst *rqst,
40 struct TCP_Server_Info *server, char *signature,
41 struct shash_desc *shash)
42{
43 int i;
44 int rc;
45 struct kvec *iov = rqst->rq_iov;
46 int n_vec = rqst->rq_nvec;
47
48 if (n_vec < 2 || iov[0].iov_len != 4)
49 return -EIO;
50
51 for (i = 1; i < n_vec; i++) {
52 if (iov[i].iov_len == 0)
53 continue;
54 if (iov[i].iov_base == NULL) {
55 cifs_dbg(VFS, "null iovec entry\n");
56 return -EIO;
57 }
58 if (i == 1 && iov[1].iov_len <= 4)
59 break; /* nothing to sign or corrupt header */
60 rc = crypto_shash_update(shash,
61 iov[i].iov_base, iov[i].iov_len);
62 if (rc) {
63 cifs_dbg(VFS, "%s: Could not update with payload\n",
64 __func__);
65 return rc;
66 }
67 }
68
69 /* now hash over the rq_pages array */
70 for (i = 0; i < rqst->rq_npages; i++) {
71 void *kaddr = kmap(rqst->rq_pages[i]);
72 size_t len = rqst->rq_pagesz;
73
74 if (i == rqst->rq_npages - 1)
75 len = rqst->rq_tailsz;
76
77 crypto_shash_update(shash, kaddr, len);
78
79 kunmap(rqst->rq_pages[i]);
80 }
81
82 rc = crypto_shash_final(shash, signature);
83 if (rc)
84 cifs_dbg(VFS, "%s: Could not generate hash\n", __func__);
85
86 return rc;
87}
88
89/*
90 * Calculate and return the CIFS signature based on the mac key and SMB PDU.
91 * The 16 byte signature must be allocated by the caller. Note we only use the
92 * 1st eight bytes and that the smb header signature field on input contains
93 * the sequence number before this function is called. Also, this function
94 * should be called with the server->srv_mutex held.
95 */
96static int cifs_calc_signature(struct smb_rqst *rqst,
97 struct TCP_Server_Info *server, char *signature)
98{
99 int rc;
100
101 if (!rqst->rq_iov || !signature || !server)
102 return -EINVAL;
103
104 rc = cifs_alloc_hash("md5", &server->secmech.md5,
105 &server->secmech.sdescmd5);
106 if (rc)
107 return -1;
108
109 rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
110 if (rc) {
111 cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
112 return rc;
113 }
114
115 rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
116 server->session_key.response, server->session_key.len);
117 if (rc) {
118 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
119 return rc;
120 }
121
122 return __cifs_calc_signature(rqst, server, signature,
123 &server->secmech.sdescmd5->shash);
124}
125
126/* must be called with server->srv_mutex held */
127int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
128 __u32 *pexpected_response_sequence_number)
129{
130 int rc = 0;
131 char smb_signature[20];
132 struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
133
134 if (rqst->rq_iov[0].iov_len != 4 ||
135 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
136 return -EIO;
137
138 if ((cifs_pdu == NULL) || (server == NULL))
139 return -EINVAL;
140
141 if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
142 server->tcpStatus == CifsNeedNegotiate)
143 return rc;
144
145 if (!server->session_estab) {
146 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
147 return rc;
148 }
149
150 cifs_pdu->Signature.Sequence.SequenceNumber =
151 cpu_to_le32(server->sequence_number);
152 cifs_pdu->Signature.Sequence.Reserved = 0;
153
154 *pexpected_response_sequence_number = ++server->sequence_number;
155 ++server->sequence_number;
156
157 rc = cifs_calc_signature(rqst, server, smb_signature);
158 if (rc)
159 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
160 else
161 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
162
163 return rc;
164}
165
166int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
167 __u32 *pexpected_response_sequence)
168{
169 struct smb_rqst rqst = { .rq_iov = iov,
170 .rq_nvec = n_vec };
171
172 return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
173}
174
175/* must be called with server->srv_mutex held */
176int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
177 __u32 *pexpected_response_sequence_number)
178{
179 struct kvec iov[2];
180
181 iov[0].iov_base = cifs_pdu;
182 iov[0].iov_len = 4;
183 iov[1].iov_base = (char *)cifs_pdu + 4;
184 iov[1].iov_len = be32_to_cpu(cifs_pdu->smb_buf_length);
185
186 return cifs_sign_smbv(iov, 2, server,
187 pexpected_response_sequence_number);
188}
189
190int cifs_verify_signature(struct smb_rqst *rqst,
191 struct TCP_Server_Info *server,
192 __u32 expected_sequence_number)
193{
194 unsigned int rc;
195 char server_response_sig[8];
196 char what_we_think_sig_should_be[20];
197 struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
198
199 if (rqst->rq_iov[0].iov_len != 4 ||
200 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
201 return -EIO;
202
203 if (cifs_pdu == NULL || server == NULL)
204 return -EINVAL;
205
206 if (!server->session_estab)
207 return 0;
208
209 if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
210 struct smb_com_lock_req *pSMB =
211 (struct smb_com_lock_req *)cifs_pdu;
212 if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
213 return 0;
214 }
215
216 /* BB what if signatures are supposed to be on for session but
217 server does not send one? BB */
218
219 /* Do not need to verify session setups with signature "BSRSPYL " */
220 if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
221 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
222 cifs_pdu->Command);
223
224 /* save off the origiginal signature so we can modify the smb and check
225 its signature against what the server sent */
226 memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
227
228 cifs_pdu->Signature.Sequence.SequenceNumber =
229 cpu_to_le32(expected_sequence_number);
230 cifs_pdu->Signature.Sequence.Reserved = 0;
231
232 mutex_lock(&server->srv_mutex);
233 rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
234 mutex_unlock(&server->srv_mutex);
235
236 if (rc)
237 return rc;
238
239/* cifs_dump_mem("what we think it should be: ",
240 what_we_think_sig_should_be, 16); */
241
242 if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
243 return -EACCES;
244 else
245 return 0;
246
247}
248
249/* first calculate 24 bytes ntlm response and then 16 byte session key */
250int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
251{
252 int rc = 0;
253 unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
254 char temp_key[CIFS_SESS_KEY_SIZE];
255
256 if (!ses)
257 return -EINVAL;
258
259 ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
260 if (!ses->auth_key.response)
261 return -ENOMEM;
262
263 ses->auth_key.len = temp_len;
264
265 rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
266 ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
267 if (rc) {
268 cifs_dbg(FYI, "%s Can't generate NTLM response, error: %d\n",
269 __func__, rc);
270 return rc;
271 }
272
273 rc = E_md4hash(ses->password, temp_key, nls_cp);
274 if (rc) {
275 cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
276 __func__, rc);
277 return rc;
278 }
279
280 rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
281 if (rc)
282 cifs_dbg(FYI, "%s Can't generate NTLM session key, error: %d\n",
283 __func__, rc);
284
285 return rc;
286}
287
288#ifdef CONFIG_CIFS_WEAK_PW_HASH
289int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
290 char *lnm_session_key)
291{
292 int i;
293 int rc;
294 char password_with_pad[CIFS_ENCPWD_SIZE] = {0};
295
296 if (password)
297 strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
298
299 if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
300 memcpy(lnm_session_key, password_with_pad,
301 CIFS_ENCPWD_SIZE);
302 return 0;
303 }
304
305 /* calculate old style session key */
306 /* calling toupper is less broken than repeatedly
307 calling nls_toupper would be since that will never
308 work for UTF8, but neither handles multibyte code pages
309 but the only alternative would be converting to UCS-16 (Unicode)
310 (using a routine something like UniStrupr) then
311 uppercasing and then converting back from Unicode - which
312 would only worth doing it if we knew it were utf8. Basically
313 utf8 and other multibyte codepages each need their own strupper
314 function since a byte at a time will ont work. */
315
316 for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
317 password_with_pad[i] = toupper(password_with_pad[i]);
318
319 rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
320
321 return rc;
322}
323#endif /* CIFS_WEAK_PW_HASH */
324
325/* Build a proper attribute value/target info pairs blob.
326 * Fill in netbios and dns domain name and workstation name
327 * and client time (total five av pairs and + one end of fields indicator.
328 * Allocate domain name which gets freed when session struct is deallocated.
329 */
330static int
331build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
332{
333 unsigned int dlen;
334 unsigned int size = 2 * sizeof(struct ntlmssp2_name);
335 char *defdmname = "WORKGROUP";
336 unsigned char *blobptr;
337 struct ntlmssp2_name *attrptr;
338
339 if (!ses->domainName) {
340 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
341 if (!ses->domainName)
342 return -ENOMEM;
343 }
344
345 dlen = strlen(ses->domainName);
346
347 /*
348 * The length of this blob is two times the size of a
349 * structure (av pair) which holds name/size
350 * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
351 * unicode length of a netbios domain name
352 */
353 ses->auth_key.len = size + 2 * dlen;
354 ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
355 if (!ses->auth_key.response) {
356 ses->auth_key.len = 0;
357 return -ENOMEM;
358 }
359
360 blobptr = ses->auth_key.response;
361 attrptr = (struct ntlmssp2_name *) blobptr;
362
363 /*
364 * As defined in MS-NTLM 3.3.2, just this av pair field
365 * is sufficient as part of the temp
366 */
367 attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
368 attrptr->length = cpu_to_le16(2 * dlen);
369 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
370 cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
371
372 return 0;
373}
374
375/* Server has provided av pairs/target info in the type 2 challenge
376 * packet and we have plucked it and stored within smb session.
377 * We parse that blob here to find netbios domain name to be used
378 * as part of ntlmv2 authentication (in Target String), if not already
379 * specified on the command line.
380 * If this function returns without any error but without fetching
381 * domain name, authentication may fail against some server but
382 * may not fail against other (those who are not very particular
383 * about target string i.e. for some, just user name might suffice.
384 */
385static int
386find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
387{
388 unsigned int attrsize;
389 unsigned int type;
390 unsigned int onesize = sizeof(struct ntlmssp2_name);
391 unsigned char *blobptr;
392 unsigned char *blobend;
393 struct ntlmssp2_name *attrptr;
394
395 if (!ses->auth_key.len || !ses->auth_key.response)
396 return 0;
397
398 blobptr = ses->auth_key.response;
399 blobend = blobptr + ses->auth_key.len;
400
401 while (blobptr + onesize < blobend) {
402 attrptr = (struct ntlmssp2_name *) blobptr;
403 type = le16_to_cpu(attrptr->type);
404 if (type == NTLMSSP_AV_EOL)
405 break;
406 blobptr += 2; /* advance attr type */
407 attrsize = le16_to_cpu(attrptr->length);
408 blobptr += 2; /* advance attr size */
409 if (blobptr + attrsize > blobend)
410 break;
411 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
412 if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
413 break;
414 if (!ses->domainName) {
415 ses->domainName =
416 kmalloc(attrsize + 1, GFP_KERNEL);
417 if (!ses->domainName)
418 return -ENOMEM;
419 cifs_from_utf16(ses->domainName,
420 (__le16 *)blobptr, attrsize, attrsize,
421 nls_cp, NO_MAP_UNI_RSVD);
422 break;
423 }
424 }
425 blobptr += attrsize; /* advance attr value */
426 }
427
428 return 0;
429}
430
431/* Server has provided av pairs/target info in the type 2 challenge
432 * packet and we have plucked it and stored within smb session.
433 * We parse that blob here to find the server given timestamp
434 * as part of ntlmv2 authentication (or local current time as
435 * default in case of failure)
436 */
437static __le64
438find_timestamp(struct cifs_ses *ses)
439{
440 unsigned int attrsize;
441 unsigned int type;
442 unsigned int onesize = sizeof(struct ntlmssp2_name);
443 unsigned char *blobptr;
444 unsigned char *blobend;
445 struct ntlmssp2_name *attrptr;
446 struct timespec ts;
447
448 if (!ses->auth_key.len || !ses->auth_key.response)
449 return 0;
450
451 blobptr = ses->auth_key.response;
452 blobend = blobptr + ses->auth_key.len;
453
454 while (blobptr + onesize < blobend) {
455 attrptr = (struct ntlmssp2_name *) blobptr;
456 type = le16_to_cpu(attrptr->type);
457 if (type == NTLMSSP_AV_EOL)
458 break;
459 blobptr += 2; /* advance attr type */
460 attrsize = le16_to_cpu(attrptr->length);
461 blobptr += 2; /* advance attr size */
462 if (blobptr + attrsize > blobend)
463 break;
464 if (type == NTLMSSP_AV_TIMESTAMP) {
465 if (attrsize == sizeof(u64))
466 return *((__le64 *)blobptr);
467 }
468 blobptr += attrsize; /* advance attr value */
469 }
470
471 ktime_get_real_ts(&ts);
472 return cpu_to_le64(cifs_UnixTimeToNT(ts));
473}
474
475static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
476 const struct nls_table *nls_cp)
477{
478 int rc = 0;
479 int len;
480 char nt_hash[CIFS_NTHASH_SIZE];
481 __le16 *user;
482 wchar_t *domain;
483 wchar_t *server;
484
485 if (!ses->server->secmech.sdeschmacmd5) {
486 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
487 return -1;
488 }
489
490 /* calculate md4 hash of password */
491 E_md4hash(ses->password, nt_hash, nls_cp);
492
493 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
494 CIFS_NTHASH_SIZE);
495 if (rc) {
496 cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
497 return rc;
498 }
499
500 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
501 if (rc) {
502 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
503 return rc;
504 }
505
506 /* convert ses->user_name to unicode */
507 len = ses->user_name ? strlen(ses->user_name) : 0;
508 user = kmalloc(2 + (len * 2), GFP_KERNEL);
509 if (user == NULL) {
510 rc = -ENOMEM;
511 return rc;
512 }
513
514 if (len) {
515 len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
516 UniStrupr(user);
517 } else {
518 memset(user, '\0', 2);
519 }
520
521 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
522 (char *)user, 2 * len);
523 kfree(user);
524 if (rc) {
525 cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
526 return rc;
527 }
528
529 /* convert ses->domainName to unicode and uppercase */
530 if (ses->domainName) {
531 len = strlen(ses->domainName);
532
533 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
534 if (domain == NULL) {
535 rc = -ENOMEM;
536 return rc;
537 }
538 len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
539 nls_cp);
540 rc =
541 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
542 (char *)domain, 2 * len);
543 kfree(domain);
544 if (rc) {
545 cifs_dbg(VFS, "%s: Could not update with domain\n",
546 __func__);
547 return rc;
548 }
549 } else {
550 /* We use ses->serverName if no domain name available */
551 len = strlen(ses->serverName);
552
553 server = kmalloc(2 + (len * 2), GFP_KERNEL);
554 if (server == NULL) {
555 rc = -ENOMEM;
556 return rc;
557 }
558 len = cifs_strtoUTF16((__le16 *)server, ses->serverName, len,
559 nls_cp);
560 rc =
561 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
562 (char *)server, 2 * len);
563 kfree(server);
564 if (rc) {
565 cifs_dbg(VFS, "%s: Could not update with server\n",
566 __func__);
567 return rc;
568 }
569 }
570
571 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
572 ntlmv2_hash);
573 if (rc)
574 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
575
576 return rc;
577}
578
579static int
580CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
581{
582 int rc;
583 struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
584 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
585 unsigned int hash_len;
586
587 /* The MD5 hash starts at challenge_key.key */
588 hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
589 offsetof(struct ntlmv2_resp, challenge.key[0]));
590
591 if (!ses->server->secmech.sdeschmacmd5) {
592 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
593 return -1;
594 }
595
596 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
597 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
598 if (rc) {
599 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
600 __func__);
601 return rc;
602 }
603
604 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
605 if (rc) {
606 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
607 return rc;
608 }
609
610 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
611 memcpy(ntlmv2->challenge.key,
612 ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
613 else
614 memcpy(ntlmv2->challenge.key,
615 ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
616 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
617 ntlmv2->challenge.key, hash_len);
618 if (rc) {
619 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
620 return rc;
621 }
622
623 /* Note that the MD5 digest over writes anon.challenge_key.key */
624 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
625 ntlmv2->ntlmv2_hash);
626 if (rc)
627 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
628
629 return rc;
630}
631
632int
633setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
634{
635 int rc;
636 int baselen;
637 unsigned int tilen;
638 struct ntlmv2_resp *ntlmv2;
639 char ntlmv2_hash[16];
640 unsigned char *tiblob = NULL; /* target info blob */
641 __le64 rsp_timestamp;
642
643 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
644 if (!ses->domainName) {
645 if (ses->domainAuto) {
646 rc = find_domain_name(ses, nls_cp);
647 if (rc) {
648 cifs_dbg(VFS, "error %d finding domain name\n",
649 rc);
650 goto setup_ntlmv2_rsp_ret;
651 }
652 } else {
653 ses->domainName = kstrdup("", GFP_KERNEL);
654 }
655 }
656 } else {
657 rc = build_avpair_blob(ses, nls_cp);
658 if (rc) {
659 cifs_dbg(VFS, "error %d building av pair blob\n", rc);
660 goto setup_ntlmv2_rsp_ret;
661 }
662 }
663
664 /* Must be within 5 minutes of the server (or in range +/-2h
665 * in case of Mac OS X), so simply carry over server timestamp
666 * (as Windows 7 does)
667 */
668 rsp_timestamp = find_timestamp(ses);
669
670 baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
671 tilen = ses->auth_key.len;
672 tiblob = ses->auth_key.response;
673
674 ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
675 if (!ses->auth_key.response) {
676 rc = -ENOMEM;
677 ses->auth_key.len = 0;
678 goto setup_ntlmv2_rsp_ret;
679 }
680 ses->auth_key.len += baselen;
681
682 ntlmv2 = (struct ntlmv2_resp *)
683 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
684 ntlmv2->blob_signature = cpu_to_le32(0x00000101);
685 ntlmv2->reserved = 0;
686 ntlmv2->time = rsp_timestamp;
687
688 get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
689 ntlmv2->reserved2 = 0;
690
691 memcpy(ses->auth_key.response + baselen, tiblob, tilen);
692
693 mutex_lock(&ses->server->srv_mutex);
694
695 rc = cifs_alloc_hash("hmac(md5)",
696 &ses->server->secmech.hmacmd5,
697 &ses->server->secmech.sdeschmacmd5);
698 if (rc) {
699 goto unlock;
700 }
701
702 /* calculate ntlmv2_hash */
703 rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
704 if (rc) {
705 cifs_dbg(VFS, "could not get v2 hash rc %d\n", rc);
706 goto unlock;
707 }
708
709 /* calculate first part of the client response (CR1) */
710 rc = CalcNTLMv2_response(ses, ntlmv2_hash);
711 if (rc) {
712 cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
713 goto unlock;
714 }
715
716 /* now calculate the session key for NTLMv2 */
717 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
718 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
719 if (rc) {
720 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
721 __func__);
722 goto unlock;
723 }
724
725 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
726 if (rc) {
727 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
728 goto unlock;
729 }
730
731 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
732 ntlmv2->ntlmv2_hash,
733 CIFS_HMAC_MD5_HASH_SIZE);
734 if (rc) {
735 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
736 goto unlock;
737 }
738
739 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
740 ses->auth_key.response);
741 if (rc)
742 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
743
744unlock:
745 mutex_unlock(&ses->server->srv_mutex);
746setup_ntlmv2_rsp_ret:
747 kfree(tiblob);
748
749 return rc;
750}
751
752int
753calc_seckey(struct cifs_ses *ses)
754{
755 int rc;
756 struct crypto_skcipher *tfm_arc4;
757 struct scatterlist sgin, sgout;
758 struct skcipher_request *req;
759 unsigned char *sec_key;
760
761 sec_key = kmalloc(CIFS_SESS_KEY_SIZE, GFP_KERNEL);
762 if (sec_key == NULL)
763 return -ENOMEM;
764
765 get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
766
767 tfm_arc4 = crypto_alloc_skcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
768 if (IS_ERR(tfm_arc4)) {
769 rc = PTR_ERR(tfm_arc4);
770 cifs_dbg(VFS, "could not allocate crypto API arc4\n");
771 goto out;
772 }
773
774 rc = crypto_skcipher_setkey(tfm_arc4, ses->auth_key.response,
775 CIFS_SESS_KEY_SIZE);
776 if (rc) {
777 cifs_dbg(VFS, "%s: Could not set response as a key\n",
778 __func__);
779 goto out_free_cipher;
780 }
781
782 req = skcipher_request_alloc(tfm_arc4, GFP_KERNEL);
783 if (!req) {
784 rc = -ENOMEM;
785 cifs_dbg(VFS, "could not allocate crypto API arc4 request\n");
786 goto out_free_cipher;
787 }
788
789 sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
790 sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
791
792 skcipher_request_set_callback(req, 0, NULL, NULL);
793 skcipher_request_set_crypt(req, &sgin, &sgout, CIFS_CPHTXT_SIZE, NULL);
794
795 rc = crypto_skcipher_encrypt(req);
796 skcipher_request_free(req);
797 if (rc) {
798 cifs_dbg(VFS, "could not encrypt session key rc: %d\n", rc);
799 goto out_free_cipher;
800 }
801
802 /* make secondary_key/nonce as session key */
803 memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
804 /* and make len as that of session key only */
805 ses->auth_key.len = CIFS_SESS_KEY_SIZE;
806
807out_free_cipher:
808 crypto_free_skcipher(tfm_arc4);
809out:
810 kfree(sec_key);
811 return rc;
812}
813
814void
815cifs_crypto_secmech_release(struct TCP_Server_Info *server)
816{
817 if (server->secmech.cmacaes) {
818 crypto_free_shash(server->secmech.cmacaes);
819 server->secmech.cmacaes = NULL;
820 }
821
822 if (server->secmech.hmacsha256) {
823 crypto_free_shash(server->secmech.hmacsha256);
824 server->secmech.hmacsha256 = NULL;
825 }
826
827 if (server->secmech.md5) {
828 crypto_free_shash(server->secmech.md5);
829 server->secmech.md5 = NULL;
830 }
831
832 if (server->secmech.sha512) {
833 crypto_free_shash(server->secmech.sha512);
834 server->secmech.sha512 = NULL;
835 }
836
837 if (server->secmech.hmacmd5) {
838 crypto_free_shash(server->secmech.hmacmd5);
839 server->secmech.hmacmd5 = NULL;
840 }
841
842 if (server->secmech.ccmaesencrypt) {
843 crypto_free_aead(server->secmech.ccmaesencrypt);
844 server->secmech.ccmaesencrypt = NULL;
845 }
846
847 if (server->secmech.ccmaesdecrypt) {
848 crypto_free_aead(server->secmech.ccmaesdecrypt);
849 server->secmech.ccmaesdecrypt = NULL;
850 }
851
852 kfree(server->secmech.sdesccmacaes);
853 server->secmech.sdesccmacaes = NULL;
854 kfree(server->secmech.sdeschmacsha256);
855 server->secmech.sdeschmacsha256 = NULL;
856 kfree(server->secmech.sdeschmacmd5);
857 server->secmech.sdeschmacmd5 = NULL;
858 kfree(server->secmech.sdescmd5);
859 server->secmech.sdescmd5 = NULL;
860 kfree(server->secmech.sdescsha512);
861 server->secmech.sdescsha512 = NULL;
862}
1/*
2 * fs/cifs/cifsencrypt.c
3 *
4 * Copyright (C) International Business Machines Corp., 2005,2013
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 * the GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22#include <linux/fs.h>
23#include <linux/slab.h>
24#include "cifspdu.h"
25#include "cifsglob.h"
26#include "cifs_debug.h"
27#include "cifs_unicode.h"
28#include "cifsproto.h"
29#include "ntlmssp.h"
30#include <linux/ctype.h>
31#include <linux/random.h>
32#include <linux/highmem.h>
33
34static int
35cifs_crypto_shash_md5_allocate(struct TCP_Server_Info *server)
36{
37 int rc;
38 unsigned int size;
39
40 if (server->secmech.sdescmd5 != NULL)
41 return 0; /* already allocated */
42
43 server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
44 if (IS_ERR(server->secmech.md5)) {
45 cifs_dbg(VFS, "could not allocate crypto md5\n");
46 rc = PTR_ERR(server->secmech.md5);
47 server->secmech.md5 = NULL;
48 return rc;
49 }
50
51 size = sizeof(struct shash_desc) +
52 crypto_shash_descsize(server->secmech.md5);
53 server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
54 if (!server->secmech.sdescmd5) {
55 crypto_free_shash(server->secmech.md5);
56 server->secmech.md5 = NULL;
57 return -ENOMEM;
58 }
59 server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
60 server->secmech.sdescmd5->shash.flags = 0x0;
61
62 return 0;
63}
64
65/*
66 * Calculate and return the CIFS signature based on the mac key and SMB PDU.
67 * The 16 byte signature must be allocated by the caller. Note we only use the
68 * 1st eight bytes and that the smb header signature field on input contains
69 * the sequence number before this function is called. Also, this function
70 * should be called with the server->srv_mutex held.
71 */
72static int cifs_calc_signature(struct smb_rqst *rqst,
73 struct TCP_Server_Info *server, char *signature)
74{
75 int i;
76 int rc;
77 struct kvec *iov = rqst->rq_iov;
78 int n_vec = rqst->rq_nvec;
79
80 if (iov == NULL || signature == NULL || server == NULL)
81 return -EINVAL;
82
83 if (!server->secmech.sdescmd5) {
84 rc = cifs_crypto_shash_md5_allocate(server);
85 if (rc) {
86 cifs_dbg(VFS, "%s: Can't alloc md5 crypto\n", __func__);
87 return -1;
88 }
89 }
90
91 rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
92 if (rc) {
93 cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
94 return rc;
95 }
96
97 rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
98 server->session_key.response, server->session_key.len);
99 if (rc) {
100 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
101 return rc;
102 }
103
104 for (i = 0; i < n_vec; i++) {
105 if (iov[i].iov_len == 0)
106 continue;
107 if (iov[i].iov_base == NULL) {
108 cifs_dbg(VFS, "null iovec entry\n");
109 return -EIO;
110 }
111 /* The first entry includes a length field (which does not get
112 signed that occupies the first 4 bytes before the header */
113 if (i == 0) {
114 if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
115 break; /* nothing to sign or corrupt header */
116 rc =
117 crypto_shash_update(&server->secmech.sdescmd5->shash,
118 iov[i].iov_base + 4, iov[i].iov_len - 4);
119 } else {
120 rc =
121 crypto_shash_update(&server->secmech.sdescmd5->shash,
122 iov[i].iov_base, iov[i].iov_len);
123 }
124 if (rc) {
125 cifs_dbg(VFS, "%s: Could not update with payload\n",
126 __func__);
127 return rc;
128 }
129 }
130
131 /* now hash over the rq_pages array */
132 for (i = 0; i < rqst->rq_npages; i++) {
133 struct kvec p_iov;
134
135 cifs_rqst_page_to_kvec(rqst, i, &p_iov);
136 crypto_shash_update(&server->secmech.sdescmd5->shash,
137 p_iov.iov_base, p_iov.iov_len);
138 kunmap(rqst->rq_pages[i]);
139 }
140
141 rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
142 if (rc)
143 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
144
145 return rc;
146}
147
148/* must be called with server->srv_mutex held */
149int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
150 __u32 *pexpected_response_sequence_number)
151{
152 int rc = 0;
153 char smb_signature[20];
154 struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
155
156 if ((cifs_pdu == NULL) || (server == NULL))
157 return -EINVAL;
158
159 if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
160 server->tcpStatus == CifsNeedNegotiate)
161 return rc;
162
163 if (!server->session_estab) {
164 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
165 return rc;
166 }
167
168 cifs_pdu->Signature.Sequence.SequenceNumber =
169 cpu_to_le32(server->sequence_number);
170 cifs_pdu->Signature.Sequence.Reserved = 0;
171
172 *pexpected_response_sequence_number = ++server->sequence_number;
173 ++server->sequence_number;
174
175 rc = cifs_calc_signature(rqst, server, smb_signature);
176 if (rc)
177 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
178 else
179 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
180
181 return rc;
182}
183
184int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
185 __u32 *pexpected_response_sequence)
186{
187 struct smb_rqst rqst = { .rq_iov = iov,
188 .rq_nvec = n_vec };
189
190 return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
191}
192
193/* must be called with server->srv_mutex held */
194int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
195 __u32 *pexpected_response_sequence_number)
196{
197 struct kvec iov;
198
199 iov.iov_base = cifs_pdu;
200 iov.iov_len = be32_to_cpu(cifs_pdu->smb_buf_length) + 4;
201
202 return cifs_sign_smbv(&iov, 1, 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 (cifs_pdu == NULL || server == NULL)
216 return -EINVAL;
217
218 if (!server->session_estab)
219 return 0;
220
221 if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
222 struct smb_com_lock_req *pSMB =
223 (struct smb_com_lock_req *)cifs_pdu;
224 if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
225 return 0;
226 }
227
228 /* BB what if signatures are supposed to be on for session but
229 server does not send one? BB */
230
231 /* Do not need to verify session setups with signature "BSRSPYL " */
232 if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
233 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
234 cifs_pdu->Command);
235
236 /* save off the origiginal signature so we can modify the smb and check
237 its signature against what the server sent */
238 memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
239
240 cifs_pdu->Signature.Sequence.SequenceNumber =
241 cpu_to_le32(expected_sequence_number);
242 cifs_pdu->Signature.Sequence.Reserved = 0;
243
244 mutex_lock(&server->srv_mutex);
245 rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
246 mutex_unlock(&server->srv_mutex);
247
248 if (rc)
249 return rc;
250
251/* cifs_dump_mem("what we think it should be: ",
252 what_we_think_sig_should_be, 16); */
253
254 if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
255 return -EACCES;
256 else
257 return 0;
258
259}
260
261/* first calculate 24 bytes ntlm response and then 16 byte session key */
262int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
263{
264 int rc = 0;
265 unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
266 char temp_key[CIFS_SESS_KEY_SIZE];
267
268 if (!ses)
269 return -EINVAL;
270
271 ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
272 if (!ses->auth_key.response)
273 return -ENOMEM;
274
275 ses->auth_key.len = temp_len;
276
277 rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
278 ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
279 if (rc) {
280 cifs_dbg(FYI, "%s Can't generate NTLM response, error: %d\n",
281 __func__, rc);
282 return rc;
283 }
284
285 rc = E_md4hash(ses->password, temp_key, nls_cp);
286 if (rc) {
287 cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
288 __func__, rc);
289 return rc;
290 }
291
292 rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
293 if (rc)
294 cifs_dbg(FYI, "%s Can't generate NTLM session key, error: %d\n",
295 __func__, rc);
296
297 return rc;
298}
299
300#ifdef CONFIG_CIFS_WEAK_PW_HASH
301int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
302 char *lnm_session_key)
303{
304 int i;
305 int rc;
306 char password_with_pad[CIFS_ENCPWD_SIZE];
307
308 memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
309 if (password)
310 strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
311
312 if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
313 memcpy(lnm_session_key, password_with_pad,
314 CIFS_ENCPWD_SIZE);
315 return 0;
316 }
317
318 /* calculate old style session key */
319 /* calling toupper is less broken than repeatedly
320 calling nls_toupper would be since that will never
321 work for UTF8, but neither handles multibyte code pages
322 but the only alternative would be converting to UCS-16 (Unicode)
323 (using a routine something like UniStrupr) then
324 uppercasing and then converting back from Unicode - which
325 would only worth doing it if we knew it were utf8. Basically
326 utf8 and other multibyte codepages each need their own strupper
327 function since a byte at a time will ont work. */
328
329 for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
330 password_with_pad[i] = toupper(password_with_pad[i]);
331
332 rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
333
334 return rc;
335}
336#endif /* CIFS_WEAK_PW_HASH */
337
338/* Build a proper attribute value/target info pairs blob.
339 * Fill in netbios and dns domain name and workstation name
340 * and client time (total five av pairs and + one end of fields indicator.
341 * Allocate domain name which gets freed when session struct is deallocated.
342 */
343static int
344build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
345{
346 unsigned int dlen;
347 unsigned int size = 2 * sizeof(struct ntlmssp2_name);
348 char *defdmname = "WORKGROUP";
349 unsigned char *blobptr;
350 struct ntlmssp2_name *attrptr;
351
352 if (!ses->domainName) {
353 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
354 if (!ses->domainName)
355 return -ENOMEM;
356 }
357
358 dlen = strlen(ses->domainName);
359
360 /*
361 * The length of this blob is two times the size of a
362 * structure (av pair) which holds name/size
363 * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
364 * unicode length of a netbios domain name
365 */
366 ses->auth_key.len = size + 2 * dlen;
367 ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
368 if (!ses->auth_key.response) {
369 ses->auth_key.len = 0;
370 return -ENOMEM;
371 }
372
373 blobptr = ses->auth_key.response;
374 attrptr = (struct ntlmssp2_name *) blobptr;
375
376 /*
377 * As defined in MS-NTLM 3.3.2, just this av pair field
378 * is sufficient as part of the temp
379 */
380 attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
381 attrptr->length = cpu_to_le16(2 * dlen);
382 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
383 cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
384
385 return 0;
386}
387
388/* Server has provided av pairs/target info in the type 2 challenge
389 * packet and we have plucked it and stored within smb session.
390 * We parse that blob here to find netbios domain name to be used
391 * as part of ntlmv2 authentication (in Target String), if not already
392 * specified on the command line.
393 * If this function returns without any error but without fetching
394 * domain name, authentication may fail against some server but
395 * may not fail against other (those who are not very particular
396 * about target string i.e. for some, just user name might suffice.
397 */
398static int
399find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
400{
401 unsigned int attrsize;
402 unsigned int type;
403 unsigned int onesize = sizeof(struct ntlmssp2_name);
404 unsigned char *blobptr;
405 unsigned char *blobend;
406 struct ntlmssp2_name *attrptr;
407
408 if (!ses->auth_key.len || !ses->auth_key.response)
409 return 0;
410
411 blobptr = ses->auth_key.response;
412 blobend = blobptr + ses->auth_key.len;
413
414 while (blobptr + onesize < blobend) {
415 attrptr = (struct ntlmssp2_name *) blobptr;
416 type = le16_to_cpu(attrptr->type);
417 if (type == NTLMSSP_AV_EOL)
418 break;
419 blobptr += 2; /* advance attr type */
420 attrsize = le16_to_cpu(attrptr->length);
421 blobptr += 2; /* advance attr size */
422 if (blobptr + attrsize > blobend)
423 break;
424 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
425 if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
426 break;
427 if (!ses->domainName) {
428 ses->domainName =
429 kmalloc(attrsize + 1, GFP_KERNEL);
430 if (!ses->domainName)
431 return -ENOMEM;
432 cifs_from_utf16(ses->domainName,
433 (__le16 *)blobptr, attrsize, attrsize,
434 nls_cp, false);
435 break;
436 }
437 }
438 blobptr += attrsize; /* advance attr value */
439 }
440
441 return 0;
442}
443
444static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
445 const struct nls_table *nls_cp)
446{
447 int rc = 0;
448 int len;
449 char nt_hash[CIFS_NTHASH_SIZE];
450 __le16 *user;
451 wchar_t *domain;
452 wchar_t *server;
453
454 if (!ses->server->secmech.sdeschmacmd5) {
455 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
456 return -1;
457 }
458
459 /* calculate md4 hash of password */
460 E_md4hash(ses->password, nt_hash, nls_cp);
461
462 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
463 CIFS_NTHASH_SIZE);
464 if (rc) {
465 cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
466 return rc;
467 }
468
469 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
470 if (rc) {
471 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
472 return rc;
473 }
474
475 /* convert ses->user_name to unicode */
476 len = ses->user_name ? strlen(ses->user_name) : 0;
477 user = kmalloc(2 + (len * 2), GFP_KERNEL);
478 if (user == NULL) {
479 rc = -ENOMEM;
480 return rc;
481 }
482
483 if (len) {
484 len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
485 UniStrupr(user);
486 } else {
487 memset(user, '\0', 2);
488 }
489
490 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
491 (char *)user, 2 * len);
492 kfree(user);
493 if (rc) {
494 cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
495 return rc;
496 }
497
498 /* convert ses->domainName to unicode and uppercase */
499 if (ses->domainName) {
500 len = strlen(ses->domainName);
501
502 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
503 if (domain == NULL) {
504 rc = -ENOMEM;
505 return rc;
506 }
507 len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
508 nls_cp);
509 rc =
510 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
511 (char *)domain, 2 * len);
512 kfree(domain);
513 if (rc) {
514 cifs_dbg(VFS, "%s: Could not update with domain\n",
515 __func__);
516 return rc;
517 }
518 } else if (ses->serverName) {
519 len = strlen(ses->serverName);
520
521 server = kmalloc(2 + (len * 2), GFP_KERNEL);
522 if (server == NULL) {
523 rc = -ENOMEM;
524 return rc;
525 }
526 len = cifs_strtoUTF16((__le16 *)server, ses->serverName, len,
527 nls_cp);
528 rc =
529 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
530 (char *)server, 2 * len);
531 kfree(server);
532 if (rc) {
533 cifs_dbg(VFS, "%s: Could not update with server\n",
534 __func__);
535 return rc;
536 }
537 }
538
539 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
540 ntlmv2_hash);
541 if (rc)
542 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
543
544 return rc;
545}
546
547static int
548CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
549{
550 int rc;
551 struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
552 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
553 unsigned int hash_len;
554
555 /* The MD5 hash starts at challenge_key.key */
556 hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
557 offsetof(struct ntlmv2_resp, challenge.key[0]));
558
559 if (!ses->server->secmech.sdeschmacmd5) {
560 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
561 return -1;
562 }
563
564 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
565 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
566 if (rc) {
567 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
568 __func__);
569 return rc;
570 }
571
572 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
573 if (rc) {
574 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
575 return rc;
576 }
577
578 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
579 memcpy(ntlmv2->challenge.key,
580 ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
581 else
582 memcpy(ntlmv2->challenge.key,
583 ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
584 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
585 ntlmv2->challenge.key, hash_len);
586 if (rc) {
587 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
588 return rc;
589 }
590
591 /* Note that the MD5 digest over writes anon.challenge_key.key */
592 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
593 ntlmv2->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 crypto_hmacmd5_alloc(struct TCP_Server_Info *server)
601{
602 int rc;
603 unsigned int size;
604
605 /* check if already allocated */
606 if (server->secmech.sdeschmacmd5)
607 return 0;
608
609 server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
610 if (IS_ERR(server->secmech.hmacmd5)) {
611 cifs_dbg(VFS, "could not allocate crypto hmacmd5\n");
612 rc = PTR_ERR(server->secmech.hmacmd5);
613 server->secmech.hmacmd5 = NULL;
614 return rc;
615 }
616
617 size = sizeof(struct shash_desc) +
618 crypto_shash_descsize(server->secmech.hmacmd5);
619 server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
620 if (!server->secmech.sdeschmacmd5) {
621 crypto_free_shash(server->secmech.hmacmd5);
622 server->secmech.hmacmd5 = NULL;
623 return -ENOMEM;
624 }
625 server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
626 server->secmech.sdeschmacmd5->shash.flags = 0x0;
627
628 return 0;
629}
630
631int
632setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
633{
634 int rc;
635 int baselen;
636 unsigned int tilen;
637 struct ntlmv2_resp *ntlmv2;
638 char ntlmv2_hash[16];
639 unsigned char *tiblob = NULL; /* target info blob */
640
641 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
642 if (!ses->domainName) {
643 rc = find_domain_name(ses, nls_cp);
644 if (rc) {
645 cifs_dbg(VFS, "error %d finding domain name\n",
646 rc);
647 goto setup_ntlmv2_rsp_ret;
648 }
649 }
650 } else {
651 rc = build_avpair_blob(ses, nls_cp);
652 if (rc) {
653 cifs_dbg(VFS, "error %d building av pair blob\n", rc);
654 goto setup_ntlmv2_rsp_ret;
655 }
656 }
657
658 baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
659 tilen = ses->auth_key.len;
660 tiblob = ses->auth_key.response;
661
662 ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
663 if (!ses->auth_key.response) {
664 rc = ENOMEM;
665 ses->auth_key.len = 0;
666 goto setup_ntlmv2_rsp_ret;
667 }
668 ses->auth_key.len += baselen;
669
670 ntlmv2 = (struct ntlmv2_resp *)
671 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
672 ntlmv2->blob_signature = cpu_to_le32(0x00000101);
673 ntlmv2->reserved = 0;
674 /* Must be within 5 minutes of the server */
675 ntlmv2->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
676 get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
677 ntlmv2->reserved2 = 0;
678
679 memcpy(ses->auth_key.response + baselen, tiblob, tilen);
680
681 rc = crypto_hmacmd5_alloc(ses->server);
682 if (rc) {
683 cifs_dbg(VFS, "could not crypto alloc hmacmd5 rc %d\n", rc);
684 goto setup_ntlmv2_rsp_ret;
685 }
686
687 /* calculate ntlmv2_hash */
688 rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
689 if (rc) {
690 cifs_dbg(VFS, "could not get v2 hash rc %d\n", rc);
691 goto setup_ntlmv2_rsp_ret;
692 }
693
694 /* calculate first part of the client response (CR1) */
695 rc = CalcNTLMv2_response(ses, ntlmv2_hash);
696 if (rc) {
697 cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
698 goto setup_ntlmv2_rsp_ret;
699 }
700
701 /* now calculate the session key for NTLMv2 */
702 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
703 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
704 if (rc) {
705 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
706 __func__);
707 goto setup_ntlmv2_rsp_ret;
708 }
709
710 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
711 if (rc) {
712 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
713 goto setup_ntlmv2_rsp_ret;
714 }
715
716 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
717 ntlmv2->ntlmv2_hash,
718 CIFS_HMAC_MD5_HASH_SIZE);
719 if (rc) {
720 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
721 goto setup_ntlmv2_rsp_ret;
722 }
723
724 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
725 ses->auth_key.response);
726 if (rc)
727 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
728
729setup_ntlmv2_rsp_ret:
730 kfree(tiblob);
731
732 return rc;
733}
734
735int
736calc_seckey(struct cifs_ses *ses)
737{
738 int rc;
739 struct crypto_blkcipher *tfm_arc4;
740 struct scatterlist sgin, sgout;
741 struct blkcipher_desc desc;
742 unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
743
744 get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
745
746 tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
747 if (IS_ERR(tfm_arc4)) {
748 rc = PTR_ERR(tfm_arc4);
749 cifs_dbg(VFS, "could not allocate crypto API arc4\n");
750 return rc;
751 }
752
753 desc.tfm = tfm_arc4;
754
755 rc = crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response,
756 CIFS_SESS_KEY_SIZE);
757 if (rc) {
758 cifs_dbg(VFS, "%s: Could not set response as a key\n",
759 __func__);
760 return rc;
761 }
762
763 sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
764 sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
765
766 rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
767 if (rc) {
768 cifs_dbg(VFS, "could not encrypt session key rc: %d\n", rc);
769 crypto_free_blkcipher(tfm_arc4);
770 return rc;
771 }
772
773 /* make secondary_key/nonce as session key */
774 memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
775 /* and make len as that of session key only */
776 ses->auth_key.len = CIFS_SESS_KEY_SIZE;
777
778 crypto_free_blkcipher(tfm_arc4);
779
780 return rc;
781}
782
783void
784cifs_crypto_shash_release(struct TCP_Server_Info *server)
785{
786 if (server->secmech.cmacaes) {
787 crypto_free_shash(server->secmech.cmacaes);
788 server->secmech.cmacaes = NULL;
789 }
790
791 if (server->secmech.hmacsha256) {
792 crypto_free_shash(server->secmech.hmacsha256);
793 server->secmech.hmacsha256 = NULL;
794 }
795
796 if (server->secmech.md5) {
797 crypto_free_shash(server->secmech.md5);
798 server->secmech.md5 = NULL;
799 }
800
801 if (server->secmech.hmacmd5) {
802 crypto_free_shash(server->secmech.hmacmd5);
803 server->secmech.hmacmd5 = NULL;
804 }
805
806 kfree(server->secmech.sdesccmacaes);
807 server->secmech.sdesccmacaes = NULL;
808 kfree(server->secmech.sdeschmacsha256);
809 server->secmech.sdeschmacsha256 = NULL;
810 kfree(server->secmech.sdeschmacmd5);
811 server->secmech.sdeschmacmd5 = NULL;
812 kfree(server->secmech.sdescmd5);
813 server->secmech.sdescmd5 = NULL;
814}