2 Unix SMB/CIFS implementation.
3 SMB parameters and setup
4 Copyright (C) Andrew Tridgell 1992-1998
5 Modified by Jeremy Allison 1995.
6 Copyright (C) Jeremy Allison 1995-2000.
7 Copyright (C) Luke Kennethc Casson Leighton 1996-2000.
8 Copyright (C) Andrew Bartlett <abartlet@samba.org> 2002-2003
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program 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 the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program. If not, see <http://www.gnu.org/licenses/>.
25 #include "system/time.h"
26 #include "../libcli/auth/msrpc_parse.h"
27 #include "../lib/crypto/crypto.h"
28 #include "../libcli/auth/libcli_auth.h"
29 #include "../librpc/gen_ndr/ntlmssp.h"
31 void SMBencrypt_hash(const uint8_t lm_hash
[16], const uint8_t *c8
, uint8_t p24
[24])
36 memcpy(p21
, lm_hash
, 16);
38 SMBOWFencrypt(p21
, c8
, p24
);
41 DEBUG(100,("SMBencrypt_hash: lm#, challenge, response\n"));
42 dump_data(100, p21
, 16);
43 dump_data(100, c8
, 8);
44 dump_data(100, p24
, 24);
49 This implements the X/Open SMB password encryption
50 It takes a password ('unix' string), a 8 byte "crypt key"
51 and puts 24 bytes of encrypted password into p24
53 Returns False if password must have been truncated to create LM hash
56 bool SMBencrypt(const char *passwd
, const uint8_t *c8
, uint8_t p24
[24])
61 ret
= E_deshash(passwd
, lm_hash
);
62 SMBencrypt_hash(lm_hash
, c8
, p24
);
67 * Creates the MD4 Hash of the users password in NT UNICODE.
68 * @param passwd password in 'unix' charset.
69 * @param p16 return password hashed with md4, caller allocated 16 byte buffer
72 bool E_md4hash(const char *passwd
, uint8_t p16
[16])
78 ret
= push_ucs2_talloc(NULL
, &wpwd
, passwd
, &len
);
79 if (!ret
|| len
< 2) {
80 /* We don't want to return fixed data, as most callers
82 mdfour(p16
, (const uint8_t *)passwd
, strlen(passwd
));
87 mdfour(p16
, (const uint8_t *)wpwd
, len
);
94 * Creates the MD5 Hash of a combination of 16 byte salt and 16 byte NT hash.
95 * @param 16 byte salt.
96 * @param 16 byte NT hash.
97 * @param 16 byte return hashed with md5, caller allocated 16 byte buffer
100 void E_md5hash(const uint8_t salt
[16], const uint8_t nthash
[16], uint8_t hash_out
[16])
102 struct MD5Context tctx
;
104 MD5Update(&tctx
, salt
, 16);
105 MD5Update(&tctx
, nthash
, 16);
106 MD5Final(hash_out
, &tctx
);
110 * Creates the DES forward-only Hash of the users password in DOS ASCII charset
111 * @param passwd password in 'unix' charset.
112 * @param p16 return password hashed with DES, caller allocated 16 byte buffer
113 * @return false if password was > 14 characters, and therefore may be incorrect, otherwise true
114 * @note p16 is filled in regardless
117 bool E_deshash(const char *passwd
, uint8_t p16
[16])
123 size_t converted_size
;
129 #if _SAMBA_BUILD_ == 3
130 mem_ctx
= talloc_tos();
134 tmpbuf
= strupper_talloc(mem_ctx
, passwd
);
135 if (tmpbuf
== NULL
) {
136 /* Too many callers don't check this result, we need to fill in the buffer with something */
137 strlcpy((char *)dospwd
, passwd
? passwd
: "", sizeof(dospwd
));
144 ret
= convert_string_error(CH_UNIX
, CH_DOS
, tmpbuf
, strlen(tmpbuf
), dospwd
, sizeof(dospwd
), &converted_size
);
147 /* Only the first 14 chars are considered, password need not
148 * be null terminated. We do this in the error and success
149 * case to avoid returning a fixed 'password' buffer, but
150 * callers should not use it when E_deshash returns false */
152 E_P16((const uint8_t *)dospwd
, p16
);
160 * Creates the MD4 and DES (LM) Hash of the users password.
161 * MD4 is of the NT Unicode, DES is of the DOS UPPERCASE password.
162 * @param passwd password in 'unix' charset.
163 * @param nt_p16 return password hashed with md4, caller allocated 16 byte buffer
164 * @param p16 return password hashed with des, caller allocated 16 byte buffer
167 /* Does both the NT and LM owfs of a user's password */
168 void nt_lm_owf_gen(const char *pwd
, uint8_t nt_p16
[16], uint8_t p16
[16])
170 /* Calculate the MD4 hash (NT compatible) of the password */
171 memset(nt_p16
, '\0', 16);
172 E_md4hash(pwd
, nt_p16
);
174 #ifdef DEBUG_PASSWORD
175 DEBUG(100,("nt_lm_owf_gen: pwd, nt#\n"));
176 dump_data(120, (const uint8_t *)pwd
, strlen(pwd
));
177 dump_data(100, nt_p16
, 16);
180 E_deshash(pwd
, (uint8_t *)p16
);
182 #ifdef DEBUG_PASSWORD
183 DEBUG(100,("nt_lm_owf_gen: pwd, lm#\n"));
184 dump_data(120, (const uint8_t *)pwd
, strlen(pwd
));
185 dump_data(100, p16
, 16);
189 /* Does both the NTLMv2 owfs of a user's password */
190 bool ntv2_owf_gen(const uint8_t owf
[16],
191 const char *user_in
, const char *domain_in
,
192 bool upper_case_domain
, /* Transform the domain into UPPER case */
197 size_t user_byte_len
;
198 size_t domain_byte_len
;
202 TALLOC_CTX
*mem_ctx
= talloc_init("ntv2_owf_gen for %s\\%s", domain_in
, user_in
);
216 user_in
= strupper_talloc(mem_ctx
, user_in
);
217 if (user_in
== NULL
) {
218 talloc_free(mem_ctx
);
222 if (upper_case_domain
) {
223 domain_in
= strupper_talloc(mem_ctx
, domain_in
);
224 if (domain_in
== NULL
) {
225 talloc_free(mem_ctx
);
230 ret
= push_ucs2_talloc(mem_ctx
, &user
, user_in
, &user_byte_len
);
232 DEBUG(0, ("push_uss2_talloc() for user failed)\n"));
233 talloc_free(mem_ctx
);
237 ret
= push_ucs2_talloc(mem_ctx
, &domain
, domain_in
, &domain_byte_len
);
239 DEBUG(0, ("push_ucs2_talloc() for domain failed\n"));
240 talloc_free(mem_ctx
);
244 SMB_ASSERT(user_byte_len
>= 2);
245 SMB_ASSERT(domain_byte_len
>= 2);
247 /* We don't want null termination */
248 user_byte_len
= user_byte_len
- 2;
249 domain_byte_len
= domain_byte_len
- 2;
251 hmac_md5_init_limK_to_64(owf
, 16, &ctx
);
252 hmac_md5_update((uint8_t *)user
, user_byte_len
, &ctx
);
253 hmac_md5_update((uint8_t *)domain
, domain_byte_len
, &ctx
);
254 hmac_md5_final(kr_buf
, &ctx
);
256 #ifdef DEBUG_PASSWORD
257 DEBUG(100, ("ntv2_owf_gen: user, domain, owfkey, kr\n"));
258 dump_data(100, (uint8_t *)user
, user_byte_len
);
259 dump_data(100, (uint8_t *)domain
, domain_byte_len
);
260 dump_data(100, owf
, 16);
261 dump_data(100, kr_buf
, 16);
264 talloc_free(mem_ctx
);
268 /* Does the des encryption from the NT or LM MD4 hash. */
269 void SMBOWFencrypt(const uint8_t passwd
[16], const uint8_t *c8
, uint8_t p24
[24])
275 memcpy(p21
, passwd
, 16);
279 /* Does the des encryption. */
281 void SMBNTencrypt_hash(const uint8_t nt_hash
[16], uint8_t *c8
, uint8_t *p24
)
286 memcpy(p21
, nt_hash
, 16);
287 SMBOWFencrypt(p21
, c8
, p24
);
289 #ifdef DEBUG_PASSWORD
290 DEBUG(100,("SMBNTencrypt: nt#, challenge, response\n"));
291 dump_data(100, p21
, 16);
292 dump_data(100, c8
, 8);
293 dump_data(100, p24
, 24);
297 /* Does the NT MD4 hash then des encryption. Plaintext version of the above. */
299 void SMBNTencrypt(const char *passwd
, uint8_t *c8
, uint8_t *p24
)
302 E_md4hash(passwd
, nt_hash
);
303 SMBNTencrypt_hash(nt_hash
, c8
, p24
);
307 /* Does the md5 encryption from the Key Response for NTLMv2. */
308 void SMBOWFencrypt_ntv2(const uint8_t kr
[16],
309 const DATA_BLOB
*srv_chal
,
310 const DATA_BLOB
*smbcli_chal
,
311 uint8_t resp_buf
[16])
315 hmac_md5_init_limK_to_64(kr
, 16, &ctx
);
316 hmac_md5_update(srv_chal
->data
, srv_chal
->length
, &ctx
);
317 hmac_md5_update(smbcli_chal
->data
, smbcli_chal
->length
, &ctx
);
318 hmac_md5_final(resp_buf
, &ctx
);
320 #ifdef DEBUG_PASSWORD
321 DEBUG(100, ("SMBOWFencrypt_ntv2: srv_chal, smbcli_chal, resp_buf\n"));
322 dump_data(100, srv_chal
->data
, srv_chal
->length
);
323 dump_data(100, smbcli_chal
->data
, smbcli_chal
->length
);
324 dump_data(100, resp_buf
, 16);
328 void SMBsesskeygen_ntv2(const uint8_t kr
[16],
329 const uint8_t * nt_resp
, uint8_t sess_key
[16])
331 /* a very nice, 128 bit, variable session key */
335 hmac_md5_init_limK_to_64(kr
, 16, &ctx
);
336 hmac_md5_update(nt_resp
, 16, &ctx
);
337 hmac_md5_final((uint8_t *)sess_key
, &ctx
);
339 #ifdef DEBUG_PASSWORD
340 DEBUG(100, ("SMBsesskeygen_ntv2:\n"));
341 dump_data(100, sess_key
, 16);
345 void SMBsesskeygen_ntv1(const uint8_t kr
[16], uint8_t sess_key
[16])
347 /* yes, this session key does not change - yes, this
348 is a problem - but it is 128 bits */
350 mdfour((uint8_t *)sess_key
, kr
, 16);
352 #ifdef DEBUG_PASSWORD
353 DEBUG(100, ("SMBsesskeygen_ntv1:\n"));
354 dump_data(100, sess_key
, 16);
358 void SMBsesskeygen_lm_sess_key(const uint8_t lm_hash
[16],
359 const uint8_t lm_resp
[24], /* only uses 8 */
360 uint8_t sess_key
[16])
362 /* Calculate the LM session key (effective length 40 bits,
363 but changes with each session) */
365 uint8_t partial_lm_hash
[14];
367 memcpy(partial_lm_hash
, lm_hash
, 8);
368 memset(partial_lm_hash
+ 8, 0xbd, 6);
370 des_crypt56(p24
, lm_resp
, partial_lm_hash
, 1);
371 des_crypt56(p24
+8, lm_resp
, partial_lm_hash
+ 7, 1);
373 memcpy(sess_key
, p24
, 16);
375 #ifdef DEBUG_PASSWORD
376 DEBUG(100, ("SMBsesskeygen_lm_sess_key: \n"));
377 dump_data(100, sess_key
, 16);
381 DATA_BLOB
NTLMv2_generate_names_blob(TALLOC_CTX
*mem_ctx
,
382 const char *hostname
,
385 DATA_BLOB names_blob
= data_blob_talloc(mem_ctx
, NULL
, 0);
387 /* Deliberately ignore return here.. */
388 if (hostname
!= NULL
) {
389 (void)msrpc_gen(mem_ctx
, &names_blob
,
391 MsvAvNbDomainName
, domain
,
392 MsvAvNbComputerName
, hostname
,
395 (void)msrpc_gen(mem_ctx
, &names_blob
,
397 MsvAvNbDomainName
, domain
,
403 static DATA_BLOB
NTLMv2_generate_client_data(TALLOC_CTX
*mem_ctx
, const DATA_BLOB
*names_blob
)
405 uint8_t client_chal
[8];
406 DATA_BLOB response
= data_blob(NULL
, 0);
407 uint8_t long_date
[8];
410 unix_to_nt_time(&nttime
, time(NULL
));
412 generate_random_buffer(client_chal
, sizeof(client_chal
));
414 push_nttime(long_date
, 0, nttime
);
416 /* See http://www.ubiqx.org/cifs/SMB.html#SMB.8.5 */
418 /* Deliberately ignore return here.. */
419 (void)msrpc_gen(mem_ctx
, &response
, "ddbbdb",
420 0x00000101, /* Header */
422 long_date
, 8, /* Timestamp */
423 client_chal
, 8, /* client challenge */
425 names_blob
->data
, names_blob
->length
); /* End of name list */
430 static DATA_BLOB
NTLMv2_generate_response(TALLOC_CTX
*out_mem_ctx
,
431 const uint8_t ntlm_v2_hash
[16],
432 const DATA_BLOB
*server_chal
,
433 const DATA_BLOB
*names_blob
)
435 uint8_t ntlmv2_response
[16];
436 DATA_BLOB ntlmv2_client_data
;
437 DATA_BLOB final_response
;
439 TALLOC_CTX
*mem_ctx
= talloc_named(out_mem_ctx
, 0,
440 "NTLMv2_generate_response internal context");
443 return data_blob(NULL
, 0);
447 /* generate some data to pass into the response function - including
448 the hostname and domain name of the server */
449 ntlmv2_client_data
= NTLMv2_generate_client_data(mem_ctx
, names_blob
);
451 /* Given that data, and the challenge from the server, generate a response */
452 SMBOWFencrypt_ntv2(ntlm_v2_hash
, server_chal
, &ntlmv2_client_data
, ntlmv2_response
);
454 final_response
= data_blob_talloc(out_mem_ctx
, NULL
, sizeof(ntlmv2_response
) + ntlmv2_client_data
.length
);
456 memcpy(final_response
.data
, ntlmv2_response
, sizeof(ntlmv2_response
));
458 memcpy(final_response
.data
+sizeof(ntlmv2_response
),
459 ntlmv2_client_data
.data
, ntlmv2_client_data
.length
);
461 talloc_free(mem_ctx
);
463 return final_response
;
466 static DATA_BLOB
LMv2_generate_response(TALLOC_CTX
*mem_ctx
,
467 const uint8_t ntlm_v2_hash
[16],
468 const DATA_BLOB
*server_chal
)
470 uint8_t lmv2_response
[16];
471 DATA_BLOB lmv2_client_data
= data_blob_talloc(mem_ctx
, NULL
, 8);
472 DATA_BLOB final_response
= data_blob_talloc(mem_ctx
, NULL
,24);
475 /* client-supplied random data */
476 generate_random_buffer(lmv2_client_data
.data
, lmv2_client_data
.length
);
478 /* Given that data, and the challenge from the server, generate a response */
479 SMBOWFencrypt_ntv2(ntlm_v2_hash
, server_chal
, &lmv2_client_data
, lmv2_response
);
480 memcpy(final_response
.data
, lmv2_response
, sizeof(lmv2_response
));
482 /* after the first 16 bytes is the random data we generated above,
483 so the server can verify us with it */
484 memcpy(final_response
.data
+sizeof(lmv2_response
),
485 lmv2_client_data
.data
, lmv2_client_data
.length
);
487 data_blob_free(&lmv2_client_data
);
489 return final_response
;
492 bool SMBNTLMv2encrypt_hash(TALLOC_CTX
*mem_ctx
,
493 const char *user
, const char *domain
, const uint8_t nt_hash
[16],
494 const DATA_BLOB
*server_chal
,
495 const DATA_BLOB
*names_blob
,
496 DATA_BLOB
*lm_response
, DATA_BLOB
*nt_response
,
497 DATA_BLOB
*lm_session_key
, DATA_BLOB
*user_session_key
)
499 uint8_t ntlm_v2_hash
[16];
501 /* We don't use the NT# directly. Instead we use it mashed up with
502 the username and domain.
503 This prevents username swapping during the auth exchange
505 if (!ntv2_owf_gen(nt_hash
, user
, domain
, true, ntlm_v2_hash
)) {
510 *nt_response
= NTLMv2_generate_response(mem_ctx
,
511 ntlm_v2_hash
, server_chal
,
513 if (user_session_key
) {
514 *user_session_key
= data_blob_talloc(mem_ctx
, NULL
, 16);
516 /* The NTLMv2 calculations also provide a session key, for signing etc later */
517 /* use only the first 16 bytes of nt_response for session key */
518 SMBsesskeygen_ntv2(ntlm_v2_hash
, nt_response
->data
, user_session_key
->data
);
525 *lm_response
= LMv2_generate_response(mem_ctx
,
526 ntlm_v2_hash
, server_chal
);
527 if (lm_session_key
) {
528 *lm_session_key
= data_blob_talloc(mem_ctx
, NULL
, 16);
530 /* The NTLMv2 calculations also provide a session key, for signing etc later */
531 /* use only the first 16 bytes of lm_response for session key */
532 SMBsesskeygen_ntv2(ntlm_v2_hash
, lm_response
->data
, lm_session_key
->data
);
539 bool SMBNTLMv2encrypt(TALLOC_CTX
*mem_ctx
,
540 const char *user
, const char *domain
,
541 const char *password
,
542 const DATA_BLOB
*server_chal
,
543 const DATA_BLOB
*names_blob
,
544 DATA_BLOB
*lm_response
, DATA_BLOB
*nt_response
,
545 DATA_BLOB
*lm_session_key
, DATA_BLOB
*user_session_key
)
548 E_md4hash(password
, nt_hash
);
550 return SMBNTLMv2encrypt_hash(mem_ctx
,
551 user
, domain
, nt_hash
, server_chal
, names_blob
,
552 lm_response
, nt_response
, lm_session_key
, user_session_key
);
555 /***********************************************************
556 encode a password buffer with a unicode password. The buffer
557 is filled with random data to make it harder to attack.
558 ************************************************************/
559 bool encode_pw_buffer(uint8_t buffer
[516], const char *password
, int string_flags
)
564 /* the incoming buffer can be any alignment. */
565 string_flags
|= STR_NOALIGN
;
567 new_pw_len
= push_string(new_pw
,
569 sizeof(new_pw
), string_flags
);
570 if (new_pw_len
== -1) {
574 memcpy(&buffer
[512 - new_pw_len
], new_pw
, new_pw_len
);
576 generate_random_buffer(buffer
, 512 - new_pw_len
);
579 * The length of the new password is in the last 4 bytes of
582 SIVAL(buffer
, 512, new_pw_len
);
588 /***********************************************************
589 decode a password buffer
590 *new_pw_len is the length in bytes of the possibly mulitbyte
591 returned password including termination.
592 ************************************************************/
594 bool decode_pw_buffer(TALLOC_CTX
*ctx
,
595 uint8_t in_buffer
[516],
598 charset_t string_charset
)
606 Warning !!! : This function is called from some rpc call.
607 The password IN the buffer may be a UNICODE string.
608 The password IN new_pwrd is an ASCII string
609 If you reuse that code somewhere else check first.
612 /* The length of the new password is in the last 4 bytes of the data buffer. */
614 byte_len
= IVAL(in_buffer
, 512);
616 #ifdef DEBUG_PASSWORD
617 dump_data(100, in_buffer
, 516);
620 /* Password cannot be longer than the size of the password buffer */
621 if ( (byte_len
< 0) || (byte_len
> 512)) {
622 DEBUG(0, ("decode_pw_buffer: incorrect password length (%d).\n", byte_len
));
623 DEBUG(0, ("decode_pw_buffer: check that 'encrypt passwords = yes'\n"));
627 /* decode into the return buffer. */
628 if (!convert_string_talloc(ctx
, string_charset
, CH_UNIX
,
629 &in_buffer
[512 - byte_len
],
633 DEBUG(0, ("decode_pw_buffer: failed to convert incoming password\n"));
637 #ifdef DEBUG_PASSWORD
638 DEBUG(100,("decode_pw_buffer: new_pwrd: "));
639 dump_data(100, (uint8_t *)*pp_new_pwrd
, *new_pw_len
);
640 DEBUG(100,("multibyte len:%lu\n", (unsigned long int)*new_pw_len
));
641 DEBUG(100,("original char len:%d\n", byte_len
/2));
647 /***********************************************************
648 Decode an arc4 encrypted password change buffer.
649 ************************************************************/
651 void encode_or_decode_arc4_passwd_buffer(unsigned char pw_buf
[532], const DATA_BLOB
*psession_key
)
653 struct MD5Context tctx
;
654 unsigned char key_out
[16];
656 /* Confounder is last 16 bytes. */
659 MD5Update(&tctx
, &pw_buf
[516], 16);
660 MD5Update(&tctx
, psession_key
->data
, psession_key
->length
);
661 MD5Final(key_out
, &tctx
);
662 /* arc4 with key_out. */
663 arcfour_crypt(pw_buf
, key_out
, 516);
666 /***********************************************************
667 encode a password buffer with an already unicode password. The
668 rest of the buffer is filled with random data to make it harder to attack.
669 ************************************************************/
670 bool set_pw_in_buffer(uint8_t buffer
[516], DATA_BLOB
*password
)
672 if (password
->length
> 512) {
676 memcpy(&buffer
[512 - password
->length
], password
->data
, password
->length
);
678 generate_random_buffer(buffer
, 512 - password
->length
);
681 * The length of the new password is in the last 4 bytes of
684 SIVAL(buffer
, 512, password
->length
);
688 /***********************************************************
689 decode a password buffer
690 *new_pw_size is the length in bytes of the extracted unicode password
691 ************************************************************/
692 bool extract_pw_from_buffer(TALLOC_CTX
*mem_ctx
,
693 uint8_t in_buffer
[516], DATA_BLOB
*new_pass
)
697 /* The length of the new password is in the last 4 bytes of the data buffer. */
699 byte_len
= IVAL(in_buffer
, 512);
701 #ifdef DEBUG_PASSWORD
702 dump_data(100, in_buffer
, 516);
705 /* Password cannot be longer than the size of the password buffer */
706 if ( (byte_len
< 0) || (byte_len
> 512)) {
710 *new_pass
= data_blob_talloc(mem_ctx
, &in_buffer
[512 - byte_len
], byte_len
);
712 if (!new_pass
->data
) {
720 /* encode a wkssvc_PasswordBuffer:
722 * similar to samr_CryptPasswordEx. Different: 8byte confounder (instead of
723 * 16byte), confounder in front of the 516 byte buffer (instead of after that
724 * buffer), calling MD5Update() first with session_key and then with confounder
725 * (vice versa in samr) - Guenther */
727 void encode_wkssvc_join_password_buffer(TALLOC_CTX
*mem_ctx
,
729 DATA_BLOB
*session_key
,
730 struct wkssvc_PasswordBuffer
**pwd_buf
)
733 struct MD5Context ctx
;
734 struct wkssvc_PasswordBuffer
*my_pwd_buf
= NULL
;
735 DATA_BLOB confounded_session_key
;
736 int confounder_len
= 8;
737 uint8_t confounder
[8];
739 my_pwd_buf
= talloc_zero(mem_ctx
, struct wkssvc_PasswordBuffer
);
744 confounded_session_key
= data_blob_talloc(mem_ctx
, NULL
, 16);
746 encode_pw_buffer(buffer
, pwd
, STR_UNICODE
);
748 generate_random_buffer((uint8_t *)confounder
, confounder_len
);
751 MD5Update(&ctx
, session_key
->data
, session_key
->length
);
752 MD5Update(&ctx
, confounder
, confounder_len
);
753 MD5Final(confounded_session_key
.data
, &ctx
);
755 arcfour_crypt_blob(buffer
, 516, &confounded_session_key
);
757 memcpy(&my_pwd_buf
->data
[0], confounder
, confounder_len
);
758 memcpy(&my_pwd_buf
->data
[8], buffer
, 516);
760 data_blob_free(&confounded_session_key
);
762 *pwd_buf
= my_pwd_buf
;
765 WERROR
decode_wkssvc_join_password_buffer(TALLOC_CTX
*mem_ctx
,
766 struct wkssvc_PasswordBuffer
*pwd_buf
,
767 DATA_BLOB
*session_key
,
771 struct MD5Context ctx
;
774 DATA_BLOB confounded_session_key
;
776 int confounder_len
= 8;
777 uint8_t confounder
[8];
782 return WERR_BAD_PASSWORD
;
785 if (session_key
->length
!= 16) {
786 DEBUG(10,("invalid session key\n"));
787 return WERR_BAD_PASSWORD
;
790 confounded_session_key
= data_blob_talloc(mem_ctx
, NULL
, 16);
792 memcpy(&confounder
, &pwd_buf
->data
[0], confounder_len
);
793 memcpy(&buffer
, &pwd_buf
->data
[8], 516);
796 MD5Update(&ctx
, session_key
->data
, session_key
->length
);
797 MD5Update(&ctx
, confounder
, confounder_len
);
798 MD5Final(confounded_session_key
.data
, &ctx
);
800 arcfour_crypt_blob(buffer
, 516, &confounded_session_key
);
802 if (!decode_pw_buffer(mem_ctx
, buffer
, pwd
, &pwd_len
, CH_UTF16
)) {
803 data_blob_free(&confounded_session_key
);
804 return WERR_BAD_PASSWORD
;
807 data_blob_free(&confounded_session_key
);