1 /*
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
9
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 2 of the License, or
13 (at your option) any later version.
14
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.
19
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24
25 #include "includes.h"
26 #include "system/time.h"
27 #include "auth/ntlmssp/ntlmssp.h"
28 #include "auth/ntlmssp/msrpc_parse.h"
29 #include "lib/crypto/crypto.h"
30 #include "libcli/auth/libcli_auth.h"
31 #include "pstring.h"
32
33 /*
34 This implements the X/Open SMB password encryption
35 It takes a password ('unix' string), a 8 byte "crypt key"
36 and puts 24 bytes of encrypted password into p24
37
38 Returns False if password must have been truncated to create LM hash
39 */
SMBencrypt(const char * passwd,const uint8_t * c8,uint8_t p24[24])40 BOOL SMBencrypt(const char *passwd, const uint8_t *c8, uint8_t p24[24])
41 {
42 BOOL ret;
43 uint8_t p21[21];
44
45 memset(p21,'\0',21);
46 ret = E_deshash(passwd, p21);
47
48 SMBOWFencrypt(p21, c8, p24);
49
50 #ifdef DEBUG_PASSWORD
51 DEBUG(100,("SMBencrypt: lm#, challenge, response\n"));
52 dump_data(100, p21, 16);
53 dump_data(100, c8, 8);
54 dump_data(100, p24, 24);
55 #endif
56
57 return ret;
58 }
59
60 /**
61 * Creates the MD4 Hash of the users password in NT UNICODE.
62 * @param passwd password in 'unix' charset.
63 * @param p16 return password hashed with md4, caller allocated 16 byte buffer
64 */
65
E_md4hash(const char * passwd,uint8_t p16[16])66 _PUBLIC_ BOOL E_md4hash(const char *passwd, uint8_t p16[16])
67 {
68 int len;
69 void *wpwd;
70
71 len = push_ucs2_talloc(NULL, &wpwd, passwd);
72 if (len < 2) {
73 /* We don't want to return fixed data, as most callers
74 * don't check */
75 mdfour(p16, passwd, strlen(passwd));
76 return False;
77 }
78
79 len -= 2;
80 mdfour(p16, wpwd, len);
81
82 talloc_free(wpwd);
83 return True;
84 }
85
86 /**
87 * Creates the DES forward-only Hash of the users password in DOS ASCII charset
88 * @param passwd password in 'unix' charset.
89 * @param p16 return password hashed with DES, caller allocated 16 byte buffer
90 * @return False if password was > 14 characters, and therefore may be incorrect, otherwise True
91 * @note p16 is filled in regardless
92 */
93
E_deshash(const char * passwd,uint8_t p16[16])94 _PUBLIC_ BOOL E_deshash(const char *passwd, uint8_t p16[16])
95 {
96 BOOL ret = True;
97 fstring dospwd;
98 ZERO_STRUCT(dospwd);
99
100 /* Password must be converted to DOS charset - null terminated, uppercase. */
101 push_string(dospwd, passwd, sizeof(dospwd), STR_ASCII|STR_UPPER|STR_TERMINATE);
102
103 /* Only the fisrt 14 chars are considered, password need not be null terminated. */
104 E_P16((const uint8_t *)dospwd, p16);
105
106 if (strlen(dospwd) > 14) {
107 ret = False;
108 }
109
110 ZERO_STRUCT(dospwd);
111
112 return ret;
113 }
114
115 /* Does both the NTLMv2 owfs of a user's password */
ntv2_owf_gen(const uint8_t owf[16],const char * user_in,const char * domain_in,BOOL upper_case_domain,uint8_t kr_buf[16])116 BOOL ntv2_owf_gen(const uint8_t owf[16],
117 const char *user_in, const char *domain_in,
118 BOOL upper_case_domain, /* Transform the domain into UPPER case */
119 uint8_t kr_buf[16])
120 {
121 void *user;
122 void *domain;
123 size_t user_byte_len;
124 size_t domain_byte_len;
125
126 HMACMD5Context ctx;
127 TALLOC_CTX *mem_ctx = talloc_init("ntv2_owf_gen for %s\\%s", domain_in, user_in);
128 if (!mem_ctx) {
129 return False;
130 }
131
132 if (!user_in) {
133 user_in = "";
134 }
135
136 if (!domain_in) {
137 domain_in = "";
138 }
139
140 user_in = strupper_talloc(mem_ctx, user_in);
141 if (user_in == NULL) {
142 talloc_free(mem_ctx);
143 return False;
144 }
145
146 if (upper_case_domain) {
147 domain_in = strupper_talloc(mem_ctx, domain_in);
148 if (domain_in == NULL) {
149 talloc_free(mem_ctx);
150 return False;
151 }
152 }
153
154 user_byte_len = push_ucs2_talloc(mem_ctx, &user, user_in);
155 if (user_byte_len == (ssize_t)-1) {
156 DEBUG(0, ("push_uss2_talloc() for user returned -1 (probably talloc() failure)\n"));
157 talloc_free(mem_ctx);
158 return False;
159 }
160
161 domain_byte_len = push_ucs2_talloc(mem_ctx, &domain, domain_in);
162 if (domain_byte_len == (ssize_t)-1) {
163 DEBUG(0, ("push_ucs2_talloc() for domain returned -1 (probably talloc() failure)\n"));
164 talloc_free(mem_ctx);
165 return False;
166 }
167
168 SMB_ASSERT(user_byte_len >= 2);
169 SMB_ASSERT(domain_byte_len >= 2);
170
171 /* We don't want null termination */
172 user_byte_len = user_byte_len - 2;
173 domain_byte_len = domain_byte_len - 2;
174
175 hmac_md5_init_limK_to_64(owf, 16, &ctx);
176 hmac_md5_update(user, user_byte_len, &ctx);
177 hmac_md5_update(domain, domain_byte_len, &ctx);
178 hmac_md5_final(kr_buf, &ctx);
179
180 #ifdef DEBUG_PASSWORD
181 DEBUG(100, ("ntv2_owf_gen: user, domain, owfkey, kr\n"));
182 dump_data(100, user, user_byte_len);
183 dump_data(100, domain, domain_byte_len);
184 dump_data(100, owf, 16);
185 dump_data(100, kr_buf, 16);
186 #endif
187
188 talloc_free(mem_ctx);
189 return True;
190 }
191
192 /* Does the des encryption from the NT or LM MD4 hash. */
SMBOWFencrypt(const uint8_t passwd[16],const uint8_t * c8,uint8_t p24[24])193 void SMBOWFencrypt(const uint8_t passwd[16], const uint8_t *c8, uint8_t p24[24])
194 {
195 uint8_t p21[21];
196
197 ZERO_STRUCT(p21);
198
199 memcpy(p21, passwd, 16);
200 E_P24(p21, c8, p24);
201 }
202
203 /* Does the NT MD4 hash then des encryption. */
204
SMBNTencrypt(const char * passwd,uint8_t * c8,uint8_t * p24)205 void SMBNTencrypt(const char *passwd, uint8_t *c8, uint8_t *p24)
206 {
207 uint8_t p21[21];
208
209 memset(p21,'\0',21);
210
211 E_md4hash(passwd, p21);
212 SMBOWFencrypt(p21, c8, p24);
213
214 #ifdef DEBUG_PASSWORD
215 DEBUG(100,("SMBNTencrypt: nt#, challenge, response\n"));
216 dump_data(100, p21, 16);
217 dump_data(100, c8, 8);
218 dump_data(100, p24, 24);
219 #endif
220 }
221
222 /* Does the md5 encryption from the Key Response for NTLMv2. */
SMBOWFencrypt_ntv2(const uint8_t kr[16],const DATA_BLOB * srv_chal,const DATA_BLOB * smbcli_chal,uint8_t resp_buf[16])223 void SMBOWFencrypt_ntv2(const uint8_t kr[16],
224 const DATA_BLOB *srv_chal,
225 const DATA_BLOB *smbcli_chal,
226 uint8_t resp_buf[16])
227 {
228 HMACMD5Context ctx;
229
230 hmac_md5_init_limK_to_64(kr, 16, &ctx);
231 hmac_md5_update(srv_chal->data, srv_chal->length, &ctx);
232 hmac_md5_update(smbcli_chal->data, smbcli_chal->length, &ctx);
233 hmac_md5_final(resp_buf, &ctx);
234
235 #ifdef DEBUG_PASSWORD
236 DEBUG(100, ("SMBOWFencrypt_ntv2: srv_chal, smbcli_chal, resp_buf\n"));
237 dump_data(100, srv_chal->data, srv_chal->length);
238 dump_data(100, smbcli_chal->data, smbcli_chal->length);
239 dump_data(100, resp_buf, 16);
240 #endif
241 }
242
SMBsesskeygen_ntv2(const uint8_t kr[16],const uint8_t * nt_resp,uint8_t sess_key[16])243 void SMBsesskeygen_ntv2(const uint8_t kr[16],
244 const uint8_t * nt_resp, uint8_t sess_key[16])
245 {
246 /* a very nice, 128 bit, variable session key */
247
248 HMACMD5Context ctx;
249
250 hmac_md5_init_limK_to_64(kr, 16, &ctx);
251 hmac_md5_update(nt_resp, 16, &ctx);
252 hmac_md5_final((uint8_t *)sess_key, &ctx);
253
254 #ifdef DEBUG_PASSWORD
255 DEBUG(100, ("SMBsesskeygen_ntv2:\n"));
256 dump_data(100, sess_key, 16);
257 #endif
258 }
259
SMBsesskeygen_ntv1(const uint8_t kr[16],uint8_t sess_key[16])260 void SMBsesskeygen_ntv1(const uint8_t kr[16], uint8_t sess_key[16])
261 {
262 /* yes, this session key does not change - yes, this
263 is a problem - but it is 128 bits */
264
265 mdfour((uint8_t *)sess_key, kr, 16);
266
267 #ifdef DEBUG_PASSWORD
268 DEBUG(100, ("SMBsesskeygen_ntv1:\n"));
269 dump_data(100, sess_key, 16);
270 #endif
271 }
272
SMBsesskeygen_lm_sess_key(const uint8_t lm_hash[16],const uint8_t lm_resp[24],uint8_t sess_key[16])273 void SMBsesskeygen_lm_sess_key(const uint8_t lm_hash[16],
274 const uint8_t lm_resp[24], /* only uses 8 */
275 uint8_t sess_key[16])
276 {
277 /* Calculate the LM session key (effective length 40 bits,
278 but changes with each session) */
279 uint8_t p24[24];
280 uint8_t partial_lm_hash[14];
281
282 memcpy(partial_lm_hash, lm_hash, 8);
283 memset(partial_lm_hash + 8, 0xbd, 6);
284
285 des_crypt56(p24, lm_resp, partial_lm_hash, 1);
286 des_crypt56(p24+8, lm_resp, partial_lm_hash + 7, 1);
287
288 memcpy(sess_key, p24, 16);
289
290 #ifdef DEBUG_PASSWORD
291 DEBUG(100, ("SMBsesskeygen_lm_sess_key: \n"));
292 dump_data(100, sess_key, 16);
293 #endif
294 }
295
NTLMv2_generate_names_blob(TALLOC_CTX * mem_ctx,const char * hostname,const char * domain)296 DATA_BLOB NTLMv2_generate_names_blob(TALLOC_CTX *mem_ctx,
297 const char *hostname,
298 const char *domain)
299 {
300 DATA_BLOB names_blob = data_blob_talloc(mem_ctx, NULL, 0);
301
302 msrpc_gen(mem_ctx, &names_blob, "aaa",
303 NTLMSSP_NAME_TYPE_DOMAIN, domain,
304 NTLMSSP_NAME_TYPE_SERVER, hostname,
305 0, "");
306 return names_blob;
307 }
308
NTLMv2_generate_client_data(TALLOC_CTX * mem_ctx,const DATA_BLOB * names_blob)309 static DATA_BLOB NTLMv2_generate_client_data(TALLOC_CTX *mem_ctx, const DATA_BLOB *names_blob)
310 {
311 uint8_t client_chal[8];
312 DATA_BLOB response = data_blob(NULL, 0);
313 uint8_t long_date[8];
314 NTTIME nttime;
315
316 unix_to_nt_time(&nttime, time(NULL));
317
318 generate_random_buffer(client_chal, sizeof(client_chal));
319
320 push_nttime(long_date, 0, nttime);
321
322 /* See http://www.ubiqx.org/cifs/SMB.html#SMB.8.5 */
323
324 msrpc_gen(mem_ctx, &response, "ddbbdb",
325 0x00000101, /* Header */
326 0, /* 'Reserved' */
327 long_date, 8, /* Timestamp */
328 client_chal, 8, /* client challenge */
329 0, /* Unknown */
330 names_blob->data, names_blob->length); /* End of name list */
331
332 return response;
333 }
334
NTLMv2_generate_response(TALLOC_CTX * out_mem_ctx,const uint8_t ntlm_v2_hash[16],const DATA_BLOB * server_chal,const DATA_BLOB * names_blob)335 static DATA_BLOB NTLMv2_generate_response(TALLOC_CTX *out_mem_ctx,
336 const uint8_t ntlm_v2_hash[16],
337 const DATA_BLOB *server_chal,
338 const DATA_BLOB *names_blob)
339 {
340 uint8_t ntlmv2_response[16];
341 DATA_BLOB ntlmv2_client_data;
342 DATA_BLOB final_response;
343
344 TALLOC_CTX *mem_ctx = talloc_named(out_mem_ctx, 0,
345 "NTLMv2_generate_response internal context");
346
347 if (!mem_ctx) {
348 return data_blob(NULL, 0);
349 }
350
351 /* NTLMv2 */
352 /* generate some data to pass into the response function - including
353 the hostname and domain name of the server */
354 ntlmv2_client_data = NTLMv2_generate_client_data(mem_ctx, names_blob);
355
356 /* Given that data, and the challenge from the server, generate a response */
357 SMBOWFencrypt_ntv2(ntlm_v2_hash, server_chal, &ntlmv2_client_data, ntlmv2_response);
358
359 final_response = data_blob_talloc(out_mem_ctx, NULL, sizeof(ntlmv2_response) + ntlmv2_client_data.length);
360
361 memcpy(final_response.data, ntlmv2_response, sizeof(ntlmv2_response));
362
363 memcpy(final_response.data+sizeof(ntlmv2_response),
364 ntlmv2_client_data.data, ntlmv2_client_data.length);
365
366 talloc_free(mem_ctx);
367
368 return final_response;
369 }
370
LMv2_generate_response(TALLOC_CTX * mem_ctx,const uint8_t ntlm_v2_hash[16],const DATA_BLOB * server_chal)371 static DATA_BLOB LMv2_generate_response(TALLOC_CTX *mem_ctx,
372 const uint8_t ntlm_v2_hash[16],
373 const DATA_BLOB *server_chal)
374 {
375 uint8_t lmv2_response[16];
376 DATA_BLOB lmv2_client_data = data_blob_talloc(mem_ctx, NULL, 8);
377 DATA_BLOB final_response = data_blob_talloc(mem_ctx, NULL,24);
378
379 /* LMv2 */
380 /* client-supplied random data */
381 generate_random_buffer(lmv2_client_data.data, lmv2_client_data.length);
382
383 /* Given that data, and the challenge from the server, generate a response */
384 SMBOWFencrypt_ntv2(ntlm_v2_hash, server_chal, &lmv2_client_data, lmv2_response);
385 memcpy(final_response.data, lmv2_response, sizeof(lmv2_response));
386
387 /* after the first 16 bytes is the random data we generated above,
388 so the server can verify us with it */
389 memcpy(final_response.data+sizeof(lmv2_response),
390 lmv2_client_data.data, lmv2_client_data.length);
391
392 data_blob_free(&lmv2_client_data);
393
394 return final_response;
395 }
396
SMBNTLMv2encrypt_hash(TALLOC_CTX * mem_ctx,const char * user,const char * domain,const uint8_t nt_hash[16],const DATA_BLOB * server_chal,const DATA_BLOB * names_blob,DATA_BLOB * lm_response,DATA_BLOB * nt_response,DATA_BLOB * lm_session_key,DATA_BLOB * user_session_key)397 BOOL SMBNTLMv2encrypt_hash(TALLOC_CTX *mem_ctx,
398 const char *user, const char *domain, const uint8_t nt_hash[16],
399 const DATA_BLOB *server_chal,
400 const DATA_BLOB *names_blob,
401 DATA_BLOB *lm_response, DATA_BLOB *nt_response,
402 DATA_BLOB *lm_session_key, DATA_BLOB *user_session_key)
403 {
404 uint8_t ntlm_v2_hash[16];
405
406 /* We don't use the NT# directly. Instead we use it mashed up with
407 the username and domain.
408 This prevents username swapping during the auth exchange
409 */
410 if (!ntv2_owf_gen(nt_hash, user, domain, True, ntlm_v2_hash)) {
411 return False;
412 }
413
414 if (nt_response) {
415 *nt_response = NTLMv2_generate_response(mem_ctx,
416 ntlm_v2_hash, server_chal,
417 names_blob);
418 if (user_session_key) {
419 *user_session_key = data_blob_talloc(mem_ctx, NULL, 16);
420
421 /* The NTLMv2 calculations also provide a session key, for signing etc later */
422 /* use only the first 16 bytes of nt_response for session key */
423 SMBsesskeygen_ntv2(ntlm_v2_hash, nt_response->data, user_session_key->data);
424 }
425 }
426
427 /* LMv2 */
428
429 if (lm_response) {
430 *lm_response = LMv2_generate_response(mem_ctx,
431 ntlm_v2_hash, server_chal);
432 if (lm_session_key) {
433 *lm_session_key = data_blob_talloc(mem_ctx, NULL, 16);
434
435 /* The NTLMv2 calculations also provide a session key, for signing etc later */
436 /* use only the first 16 bytes of lm_response for session key */
437 SMBsesskeygen_ntv2(ntlm_v2_hash, lm_response->data, lm_session_key->data);
438 }
439 }
440
441 return True;
442 }
443
SMBNTLMv2encrypt(TALLOC_CTX * mem_ctx,const char * user,const char * domain,const char * password,const DATA_BLOB * server_chal,const DATA_BLOB * names_blob,DATA_BLOB * lm_response,DATA_BLOB * nt_response,DATA_BLOB * lm_session_key,DATA_BLOB * user_session_key)444 BOOL SMBNTLMv2encrypt(TALLOC_CTX *mem_ctx,
445 const char *user, const char *domain,
446 const char *password,
447 const DATA_BLOB *server_chal,
448 const DATA_BLOB *names_blob,
449 DATA_BLOB *lm_response, DATA_BLOB *nt_response,
450 DATA_BLOB *lm_session_key, DATA_BLOB *user_session_key)
451 {
452 uint8_t nt_hash[16];
453 E_md4hash(password, nt_hash);
454
455 return SMBNTLMv2encrypt_hash(mem_ctx,
456 user, domain, nt_hash, server_chal, names_blob,
457 lm_response, nt_response, lm_session_key, user_session_key);
458 }
459
460 /***********************************************************
461 encode a password buffer with a unicode password. The buffer
462 is filled with random data to make it harder to attack.
463 ************************************************************/
encode_pw_buffer(uint8_t buffer[516],const char * password,int string_flags)464 BOOL encode_pw_buffer(uint8_t buffer[516], const char *password, int string_flags)
465 {
466 uint8_t new_pw[512];
467 size_t new_pw_len;
468
469 /* the incoming buffer can be any alignment. */
470 string_flags |= STR_NOALIGN;
471
472 new_pw_len = push_string(new_pw,
473 password,
474 sizeof(new_pw), string_flags);
475
476 memcpy(&buffer[512 - new_pw_len], new_pw, new_pw_len);
477
478 generate_random_buffer(buffer, 512 - new_pw_len);
479
480 /*
481 * The length of the new password is in the last 4 bytes of
482 * the data buffer.
483 */
484 SIVAL(buffer, 512, new_pw_len);
485 ZERO_STRUCT(new_pw);
486 return True;
487 }
488
489
490 /***********************************************************
491 decode a password buffer
492 *new_pw_len is the length in bytes of the possibly mulitbyte
493 returned password including termination.
494 ************************************************************/
decode_pw_buffer(uint8_t in_buffer[516],char * new_pwrd,int new_pwrd_size,uint32_t * new_pw_len,int string_flags)495 BOOL decode_pw_buffer(uint8_t in_buffer[516], char *new_pwrd,
496 int new_pwrd_size, uint32_t *new_pw_len,
497 int string_flags)
498 {
499 int byte_len=0;
500
501 /* the incoming buffer can be any alignment. */
502 string_flags |= STR_NOALIGN;
503
504 /*
505 Warning !!! : This function is called from some rpc call.
506 The password IN the buffer may be a UNICODE string.
507 The password IN new_pwrd is an ASCII string
508 If you reuse that code somewhere else check first.
509 */
510
511 /* The length of the new password is in the last 4 bytes of the data buffer. */
512
513 byte_len = IVAL(in_buffer, 512);
514
515 #ifdef DEBUG_PASSWORD
516 dump_data(100, in_buffer, 516);
517 #endif
518
519 /* Password cannot be longer than the size of the password buffer */
520 if ( (byte_len < 0) || (byte_len > 512)) {
521 return False;
522 }
523
524 /* decode into the return buffer. Buffer length supplied */
525 *new_pw_len = pull_string(new_pwrd, &in_buffer[512 - byte_len], new_pwrd_size,
526 byte_len, string_flags);
527
528 #ifdef DEBUG_PASSWORD
529 DEBUG(100,("decode_pw_buffer: new_pwrd: "));
530 dump_data(100, (const uint8_t *)new_pwrd, *new_pw_len);
531 DEBUG(100,("multibyte len:%d\n", *new_pw_len));
532 DEBUG(100,("original char len:%d\n", byte_len/2));
533 #endif
534
535 return True;
536 }
537