2
* fs/cifs/cifsencrypt.c
4
* Copyright (C) International Business Machines Corp., 2005,2006
5
* Author(s): Steve French (sfrench@us.ibm.com)
7
* This library is free software; you can redistribute it and/or modify
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* 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.
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* 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
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* the GNU Lesser General Public License for more details.
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* You should have received a copy of the GNU Lesser General Public License
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* along with this library; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23
#include <linux/slab.h>
26
#include "cifs_debug.h"
27
#include "cifs_unicode.h"
28
#include "cifsproto.h"
30
#include <linux/ctype.h>
31
#include <linux/random.h>
34
* Calculate and return the CIFS signature based on the mac key and SMB PDU.
35
* The 16 byte signature must be allocated by the caller. Note we only use the
36
* 1st eight bytes and that the smb header signature field on input contains
37
* the sequence number before this function is called. Also, this function
38
* should be called with the server->srv_mutex held.
40
static int cifs_calc_signature(const struct kvec *iov, int n_vec,
41
struct TCP_Server_Info *server, char *signature)
46
if (iov == NULL || signature == NULL || server == NULL)
49
if (!server->secmech.sdescmd5) {
50
cERROR(1, "%s: Can't generate signature\n", __func__);
54
rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
56
cERROR(1, "%s: Could not init md5\n", __func__);
60
rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
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server->session_key.response, server->session_key.len);
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cERROR(1, "%s: Could not update with response\n", __func__);
67
for (i = 0; i < n_vec; i++) {
68
if (iov[i].iov_len == 0)
70
if (iov[i].iov_base == NULL) {
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cERROR(1, "null iovec entry");
74
/* The first entry includes a length field (which does not get
75
signed that occupies the first 4 bytes before the header */
77
if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
78
break; /* nothing to sign or corrupt header */
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crypto_shash_update(&server->secmech.sdescmd5->shash,
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iov[i].iov_base + 4, iov[i].iov_len - 4);
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crypto_shash_update(&server->secmech.sdescmd5->shash,
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iov[i].iov_base, iov[i].iov_len);
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cERROR(1, "%s: Could not update with payload\n",
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rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
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cERROR(1, "%s: Could not generate md5 hash\n", __func__);
101
/* must be called with server->srv_mutex held */
102
int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
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__u32 *pexpected_response_sequence_number)
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char smb_signature[20];
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struct smb_hdr *cifs_pdu = (struct smb_hdr *)iov[0].iov_base;
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if ((cifs_pdu == NULL) || (server == NULL))
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if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
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server->tcpStatus == CifsNeedNegotiate)
116
if (!server->session_estab) {
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memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
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cifs_pdu->Signature.Sequence.SequenceNumber =
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cpu_to_le32(server->sequence_number);
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cifs_pdu->Signature.Sequence.Reserved = 0;
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*pexpected_response_sequence_number = server->sequence_number++;
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server->sequence_number++;
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rc = cifs_calc_signature(iov, n_vec, server, smb_signature);
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memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
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memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
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/* must be called with server->srv_mutex held */
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int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
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__u32 *pexpected_response_sequence_number)
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iov.iov_base = cifs_pdu;
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iov.iov_len = be32_to_cpu(cifs_pdu->smb_buf_length) + 4;
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return cifs_sign_smb2(&iov, 1, server,
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pexpected_response_sequence_number);
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int cifs_verify_signature(struct kvec *iov, unsigned int nr_iov,
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struct TCP_Server_Info *server,
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__u32 expected_sequence_number)
155
char server_response_sig[8];
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char what_we_think_sig_should_be[20];
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struct smb_hdr *cifs_pdu = (struct smb_hdr *)iov[0].iov_base;
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if (cifs_pdu == NULL || server == NULL)
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if (!server->session_estab)
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if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
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struct smb_com_lock_req *pSMB =
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(struct smb_com_lock_req *)cifs_pdu;
168
if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
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/* BB what if signatures are supposed to be on for session but
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server does not send one? BB */
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/* Do not need to verify session setups with signature "BSRSPYL " */
176
if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
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cFYI(1, "dummy signature received for smb command 0x%x",
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/* save off the origiginal signature so we can modify the smb and check
181
its signature against what the server sent */
182
memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
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cifs_pdu->Signature.Sequence.SequenceNumber =
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cpu_to_le32(expected_sequence_number);
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cifs_pdu->Signature.Sequence.Reserved = 0;
188
mutex_lock(&server->srv_mutex);
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rc = cifs_calc_signature(iov, nr_iov, server,
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what_we_think_sig_should_be);
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mutex_unlock(&server->srv_mutex);
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/* cifs_dump_mem("what we think it should be: ",
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what_we_think_sig_should_be, 16); */
199
if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
206
/* first calculate 24 bytes ntlm response and then 16 byte session key */
207
int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
210
unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
211
char temp_key[CIFS_SESS_KEY_SIZE];
216
ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
217
if (!ses->auth_key.response) {
218
cERROR(1, "NTLM can't allocate (%u bytes) memory", temp_len);
221
ses->auth_key.len = temp_len;
223
rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
224
ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
226
cFYI(1, "%s Can't generate NTLM response, error: %d",
231
rc = E_md4hash(ses->password, temp_key, nls_cp);
233
cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
237
rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
239
cFYI(1, "%s Can't generate NTLM session key, error: %d",
245
#ifdef CONFIG_CIFS_WEAK_PW_HASH
246
int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
247
char *lnm_session_key)
251
char password_with_pad[CIFS_ENCPWD_SIZE];
253
memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
255
strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
257
if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
258
memset(lnm_session_key, 0, CIFS_SESS_KEY_SIZE);
259
memcpy(lnm_session_key, password_with_pad,
264
/* calculate old style session key */
265
/* calling toupper is less broken than repeatedly
266
calling nls_toupper would be since that will never
267
work for UTF8, but neither handles multibyte code pages
268
but the only alternative would be converting to UCS-16 (Unicode)
269
(using a routine something like UniStrupr) then
270
uppercasing and then converting back from Unicode - which
271
would only worth doing it if we knew it were utf8. Basically
272
utf8 and other multibyte codepages each need their own strupper
273
function since a byte at a time will ont work. */
275
for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
276
password_with_pad[i] = toupper(password_with_pad[i]);
278
rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
282
#endif /* CIFS_WEAK_PW_HASH */
284
/* Build a proper attribute value/target info pairs blob.
285
* Fill in netbios and dns domain name and workstation name
286
* and client time (total five av pairs and + one end of fields indicator.
287
* Allocate domain name which gets freed when session struct is deallocated.
290
build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
293
unsigned int size = 2 * sizeof(struct ntlmssp2_name);
294
char *defdmname = "WORKGROUP";
295
unsigned char *blobptr;
296
struct ntlmssp2_name *attrptr;
298
if (!ses->domainName) {
299
ses->domainName = kstrdup(defdmname, GFP_KERNEL);
300
if (!ses->domainName)
304
dlen = strlen(ses->domainName);
307
* The length of this blob is two times the size of a
308
* structure (av pair) which holds name/size
309
* ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
310
* unicode length of a netbios domain name
312
ses->auth_key.len = size + 2 * dlen;
313
ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
314
if (!ses->auth_key.response) {
315
ses->auth_key.len = 0;
316
cERROR(1, "Challenge target info allocation failure");
320
blobptr = ses->auth_key.response;
321
attrptr = (struct ntlmssp2_name *) blobptr;
324
* As defined in MS-NTLM 3.3.2, just this av pair field
325
* is sufficient as part of the temp
327
attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
328
attrptr->length = cpu_to_le16(2 * dlen);
329
blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
330
cifs_strtoUCS((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
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/* Server has provided av pairs/target info in the type 2 challenge
336
* packet and we have plucked it and stored within smb session.
337
* We parse that blob here to find netbios domain name to be used
338
* as part of ntlmv2 authentication (in Target String), if not already
339
* specified on the command line.
340
* If this function returns without any error but without fetching
341
* domain name, authentication may fail against some server but
342
* may not fail against other (those who are not very particular
343
* about target string i.e. for some, just user name might suffice.
346
find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
348
unsigned int attrsize;
350
unsigned int onesize = sizeof(struct ntlmssp2_name);
351
unsigned char *blobptr;
352
unsigned char *blobend;
353
struct ntlmssp2_name *attrptr;
355
if (!ses->auth_key.len || !ses->auth_key.response)
358
blobptr = ses->auth_key.response;
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blobend = blobptr + ses->auth_key.len;
361
while (blobptr + onesize < blobend) {
362
attrptr = (struct ntlmssp2_name *) blobptr;
363
type = le16_to_cpu(attrptr->type);
364
if (type == NTLMSSP_AV_EOL)
366
blobptr += 2; /* advance attr type */
367
attrsize = le16_to_cpu(attrptr->length);
368
blobptr += 2; /* advance attr size */
369
if (blobptr + attrsize > blobend)
371
if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
374
if (!ses->domainName) {
376
kmalloc(attrsize + 1, GFP_KERNEL);
377
if (!ses->domainName)
379
cifs_from_ucs2(ses->domainName,
380
(__le16 *)blobptr, attrsize, attrsize,
385
blobptr += attrsize; /* advance attr value */
391
static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
392
const struct nls_table *nls_cp)
396
char nt_hash[CIFS_NTHASH_SIZE];
401
if (!ses->server->secmech.sdeschmacmd5) {
402
cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
406
/* calculate md4 hash of password */
407
E_md4hash(ses->password, nt_hash, nls_cp);
409
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
412
cERROR(1, "%s: Could not set NT Hash as a key", __func__);
416
rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
418
cERROR(1, "calc_ntlmv2_hash: could not init hmacmd5\n");
422
/* convert ses->user_name to unicode and uppercase */
423
len = strlen(ses->user_name);
424
user = kmalloc(2 + (len * 2), GFP_KERNEL);
426
cERROR(1, "calc_ntlmv2_hash: user mem alloc failure\n");
430
len = cifs_strtoUCS((__le16 *)user, ses->user_name, len, nls_cp);
433
rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
434
(char *)user, 2 * len);
437
cERROR(1, "%s: Could not update with user\n", __func__);
441
/* convert ses->domainName to unicode and uppercase */
442
if (ses->domainName) {
443
len = strlen(ses->domainName);
445
domain = kmalloc(2 + (len * 2), GFP_KERNEL);
446
if (domain == NULL) {
447
cERROR(1, "calc_ntlmv2_hash: domain mem alloc failure");
451
len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len,
454
crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
455
(char *)domain, 2 * len);
458
cERROR(1, "%s: Could not update with domain\n",
462
} else if (ses->serverName) {
463
len = strlen(ses->serverName);
465
server = kmalloc(2 + (len * 2), GFP_KERNEL);
466
if (server == NULL) {
467
cERROR(1, "calc_ntlmv2_hash: server mem alloc failure");
471
len = cifs_strtoUCS((__le16 *)server, ses->serverName, len,
474
crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
475
(char *)server, 2 * len);
478
cERROR(1, "%s: Could not update with server\n",
484
rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
487
cERROR(1, "%s: Could not generate md5 hash\n", __func__);
493
CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
496
unsigned int offset = CIFS_SESS_KEY_SIZE + 8;
498
if (!ses->server->secmech.sdeschmacmd5) {
499
cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
503
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
504
ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
506
cERROR(1, "%s: Could not set NTLMV2 Hash as a key", __func__);
510
rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
512
cERROR(1, "CalcNTLMv2_response: could not init hmacmd5");
516
if (ses->server->secType == RawNTLMSSP)
517
memcpy(ses->auth_key.response + offset,
518
ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
520
memcpy(ses->auth_key.response + offset,
521
ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
522
rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
523
ses->auth_key.response + offset, ses->auth_key.len - offset);
525
cERROR(1, "%s: Could not update with response\n", __func__);
529
rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
530
ses->auth_key.response + CIFS_SESS_KEY_SIZE);
532
cERROR(1, "%s: Could not generate md5 hash\n", __func__);
539
setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
544
struct ntlmv2_resp *buf;
545
char ntlmv2_hash[16];
546
unsigned char *tiblob = NULL; /* target info blob */
548
if (ses->server->secType == RawNTLMSSP) {
549
if (!ses->domainName) {
550
rc = find_domain_name(ses, nls_cp);
552
cERROR(1, "error %d finding domain name", rc);
553
goto setup_ntlmv2_rsp_ret;
557
rc = build_avpair_blob(ses, nls_cp);
559
cERROR(1, "error %d building av pair blob", rc);
560
goto setup_ntlmv2_rsp_ret;
564
baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
565
tilen = ses->auth_key.len;
566
tiblob = ses->auth_key.response;
568
ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
569
if (!ses->auth_key.response) {
571
ses->auth_key.len = 0;
572
cERROR(1, "%s: Can't allocate auth blob", __func__);
573
goto setup_ntlmv2_rsp_ret;
575
ses->auth_key.len += baselen;
577
buf = (struct ntlmv2_resp *)
578
(ses->auth_key.response + CIFS_SESS_KEY_SIZE);
579
buf->blob_signature = cpu_to_le32(0x00000101);
581
buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
582
get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
585
memcpy(ses->auth_key.response + baselen, tiblob, tilen);
587
/* calculate ntlmv2_hash */
588
rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
590
cERROR(1, "could not get v2 hash rc %d", rc);
591
goto setup_ntlmv2_rsp_ret;
594
/* calculate first part of the client response (CR1) */
595
rc = CalcNTLMv2_response(ses, ntlmv2_hash);
597
cERROR(1, "Could not calculate CR1 rc: %d", rc);
598
goto setup_ntlmv2_rsp_ret;
601
/* now calculate the session key for NTLMv2 */
602
rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
603
ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
605
cERROR(1, "%s: Could not set NTLMV2 Hash as a key", __func__);
606
goto setup_ntlmv2_rsp_ret;
609
rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
611
cERROR(1, "%s: Could not init hmacmd5\n", __func__);
612
goto setup_ntlmv2_rsp_ret;
615
rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
616
ses->auth_key.response + CIFS_SESS_KEY_SIZE,
617
CIFS_HMAC_MD5_HASH_SIZE);
619
cERROR(1, "%s: Could not update with response\n", __func__);
620
goto setup_ntlmv2_rsp_ret;
623
rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
624
ses->auth_key.response);
626
cERROR(1, "%s: Could not generate md5 hash\n", __func__);
628
setup_ntlmv2_rsp_ret:
635
calc_seckey(struct cifs_ses *ses)
638
struct crypto_blkcipher *tfm_arc4;
639
struct scatterlist sgin, sgout;
640
struct blkcipher_desc desc;
641
unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
643
get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
645
tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
646
if (IS_ERR(tfm_arc4)) {
647
rc = PTR_ERR(tfm_arc4);
648
cERROR(1, "could not allocate crypto API arc4\n");
654
rc = crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response,
657
cERROR(1, "%s: Could not set response as a key", __func__);
661
sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
662
sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
664
rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
666
cERROR(1, "could not encrypt session key rc: %d\n", rc);
667
crypto_free_blkcipher(tfm_arc4);
671
/* make secondary_key/nonce as session key */
672
memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
673
/* and make len as that of session key only */
674
ses->auth_key.len = CIFS_SESS_KEY_SIZE;
676
crypto_free_blkcipher(tfm_arc4);
682
cifs_crypto_shash_release(struct TCP_Server_Info *server)
684
if (server->secmech.md5)
685
crypto_free_shash(server->secmech.md5);
687
if (server->secmech.hmacmd5)
688
crypto_free_shash(server->secmech.hmacmd5);
690
kfree(server->secmech.sdeschmacmd5);
692
kfree(server->secmech.sdescmd5);
696
cifs_crypto_shash_allocate(struct TCP_Server_Info *server)
701
server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
702
if (IS_ERR(server->secmech.hmacmd5)) {
703
cERROR(1, "could not allocate crypto hmacmd5\n");
704
return PTR_ERR(server->secmech.hmacmd5);
707
server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
708
if (IS_ERR(server->secmech.md5)) {
709
cERROR(1, "could not allocate crypto md5\n");
710
rc = PTR_ERR(server->secmech.md5);
711
goto crypto_allocate_md5_fail;
714
size = sizeof(struct shash_desc) +
715
crypto_shash_descsize(server->secmech.hmacmd5);
716
server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
717
if (!server->secmech.sdeschmacmd5) {
718
cERROR(1, "cifs_crypto_shash_allocate: can't alloc hmacmd5\n");
720
goto crypto_allocate_hmacmd5_sdesc_fail;
722
server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
723
server->secmech.sdeschmacmd5->shash.flags = 0x0;
726
size = sizeof(struct shash_desc) +
727
crypto_shash_descsize(server->secmech.md5);
728
server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
729
if (!server->secmech.sdescmd5) {
730
cERROR(1, "cifs_crypto_shash_allocate: can't alloc md5\n");
732
goto crypto_allocate_md5_sdesc_fail;
734
server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
735
server->secmech.sdescmd5->shash.flags = 0x0;
739
crypto_allocate_md5_sdesc_fail:
740
kfree(server->secmech.sdeschmacmd5);
742
crypto_allocate_hmacmd5_sdesc_fail:
743
crypto_free_shash(server->secmech.md5);
745
crypto_allocate_md5_fail:
746
crypto_free_shash(server->secmech.hmacmd5);