1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
|
/*
Unix SMB/CIFS implementation.
User credentials handling
Copyright (C) Andrew Tridgell 2001
Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2005
Copyright (C) Stefan Metzmacher 2005
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "librpc/gen_ndr/samr.h" /* for struct samrPassword */
#include "../lib/crypto/crypto.h"
#include "libcli/auth/libcli_auth.h"
#include "auth/credentials/credentials.h"
_PUBLIC_ NTSTATUS cli_credentials_get_ntlm_response(struct cli_credentials *cred, TALLOC_CTX *mem_ctx,
int *flags,
DATA_BLOB challenge, DATA_BLOB target_info,
DATA_BLOB *_lm_response, DATA_BLOB *_nt_response,
DATA_BLOB *_lm_session_key, DATA_BLOB *_session_key)
{
const char *user, *domain;
DATA_BLOB lm_response, nt_response;
DATA_BLOB lm_session_key, session_key;
const struct samr_Password *nt_hash;
lm_session_key = data_blob(NULL, 0);
/* We may already have an NTLM response we prepared earlier.
* This is used for NTLM pass-though authentication */
if (cred->nt_response.data || cred->lm_response.data) {
*_nt_response = cred->nt_response;
*_lm_response = cred->lm_response;
if (!cred->lm_response.data) {
*flags = *flags & ~CLI_CRED_LANMAN_AUTH;
}
*_lm_session_key = data_blob(NULL, 0);
*_session_key = data_blob(NULL, 0);
return NT_STATUS_OK;
}
nt_hash = cli_credentials_get_nt_hash(cred, mem_ctx);
cli_credentials_get_ntlm_username_domain(cred, mem_ctx, &user, &domain);
/* If we are sending a username@realm login (see function
* above), then we will not send LM, it will not be
* accepted */
if (cred->principal_obtained > cred->username_obtained) {
*flags = *flags & ~CLI_CRED_LANMAN_AUTH;
}
/* Likewise if we are a machine account (avoid protocol downgrade attacks) */
if (cred->machine_account) {
*flags = *flags & ~CLI_CRED_LANMAN_AUTH;
}
if (cred->use_kerberos == CRED_MUST_USE_KERBEROS) {
return NT_STATUS_ACCESS_DENIED;
}
if (!nt_hash) {
static const uint8_t zeros[16];
/* do nothing - blobs are zero length */
/* session key is all zeros */
session_key = data_blob_talloc(mem_ctx, zeros, 16);
lm_session_key = data_blob_talloc(mem_ctx, zeros, 16);
lm_response = data_blob(NULL, 0);
nt_response = data_blob(NULL, 0);
/* not doing NTLM2 without a password */
*flags &= ~CLI_CRED_NTLM2;
} else if (*flags & CLI_CRED_NTLMv2_AUTH) {
if (!target_info.length) {
/* be lazy, match win2k - we can't do NTLMv2 without it */
DEBUG(1, ("Server did not provide 'target information', required for NTLMv2\n"));
return NT_STATUS_INVALID_PARAMETER;
}
/* TODO: if the remote server is standalone, then we should replace 'domain'
with the server name as supplied above */
if (!SMBNTLMv2encrypt_hash(mem_ctx,
user,
domain,
nt_hash->hash, &challenge,
&target_info,
&lm_response, &nt_response,
NULL, &session_key)) {
return NT_STATUS_NO_MEMORY;
}
/* LM Key is incompatible... */
*flags &= ~CLI_CRED_LANMAN_AUTH;
} else if (*flags & CLI_CRED_NTLM2) {
struct MD5Context md5_session_nonce_ctx;
uint8_t session_nonce[16];
uint8_t session_nonce_hash[16];
uint8_t user_session_key[16];
lm_response = data_blob_talloc(mem_ctx, NULL, 24);
generate_random_buffer(lm_response.data, 8);
memset(lm_response.data+8, 0, 16);
memcpy(session_nonce, challenge.data, 8);
memcpy(&session_nonce[8], lm_response.data, 8);
MD5Init(&md5_session_nonce_ctx);
MD5Update(&md5_session_nonce_ctx, challenge.data, 8);
MD5Update(&md5_session_nonce_ctx, lm_response.data, 8);
MD5Final(session_nonce_hash, &md5_session_nonce_ctx);
DEBUG(5, ("NTLMSSP challenge set by NTLM2\n"));
DEBUG(5, ("challenge is: \n"));
dump_data(5, session_nonce_hash, 8);
nt_response = data_blob_talloc(mem_ctx, NULL, 24);
SMBOWFencrypt(nt_hash->hash,
session_nonce_hash,
nt_response.data);
session_key = data_blob_talloc(mem_ctx, NULL, 16);
SMBsesskeygen_ntv1(nt_hash->hash, user_session_key);
hmac_md5(user_session_key, session_nonce, sizeof(session_nonce), session_key.data);
dump_data_pw("NTLM2 session key:\n", session_key.data, session_key.length);
/* LM Key is incompatible... */
*flags &= ~CLI_CRED_LANMAN_AUTH;
} else {
uint8_t lm_hash[16];
nt_response = data_blob_talloc(mem_ctx, NULL, 24);
SMBOWFencrypt(nt_hash->hash, challenge.data,
nt_response.data);
session_key = data_blob_talloc(mem_ctx, NULL, 16);
SMBsesskeygen_ntv1(nt_hash->hash, session_key.data);
dump_data_pw("NT session key:\n", session_key.data, session_key.length);
/* lanman auth is insecure, it may be disabled.
We may also not have a password */
if (*flags & CLI_CRED_LANMAN_AUTH) {
const char *password;
password = cli_credentials_get_password(cred);
if (!password) {
lm_response = nt_response;
} else {
lm_response = data_blob_talloc(mem_ctx, NULL, 24);
if (!SMBencrypt(password,challenge.data,
lm_response.data)) {
/* If the LM password was too long (and therefore the LM hash being
of the first 14 chars only), don't send it.
We don't have any better options but to send the NT response
*/
data_blob_free(&lm_response);
lm_response = nt_response;
/* LM Key is incompatible with 'long' passwords */
*flags &= ~CLI_CRED_LANMAN_AUTH;
} else {
E_deshash(password, lm_hash);
lm_session_key = data_blob_talloc(mem_ctx, NULL, 16);
memcpy(lm_session_key.data, lm_hash, 8);
memset(&lm_session_key.data[8], '\0', 8);
if (!(*flags & CLI_CRED_NTLM_AUTH)) {
session_key = lm_session_key;
}
}
}
} else {
const char *password;
/* LM Key is incompatible... */
lm_response = nt_response;
*flags &= ~CLI_CRED_LANMAN_AUTH;
password = cli_credentials_get_password(cred);
if (password) {
E_deshash(password, lm_hash);
lm_session_key = data_blob_talloc(mem_ctx, NULL, 16);
memcpy(lm_session_key.data, lm_hash, 8);
memset(&lm_session_key.data[8], '\0', 8);
}
}
}
if (_lm_response) {
*_lm_response = lm_response;
}
if (_nt_response) {
*_nt_response = nt_response;
}
if (_lm_session_key) {
*_lm_session_key = lm_session_key;
}
if (_session_key) {
*_session_key = session_key;
}
return NT_STATUS_OK;
}
_PUBLIC_ bool cli_credentials_set_nt_hash(struct cli_credentials *cred,
const struct samr_Password *nt_hash,
enum credentials_obtained obtained)
{
if (obtained >= cred->password_obtained) {
cli_credentials_set_password(cred, NULL, obtained);
if (nt_hash) {
cred->nt_hash = talloc(cred, struct samr_Password);
*cred->nt_hash = *nt_hash;
} else {
cred->nt_hash = NULL;
}
return true;
}
return false;
}
_PUBLIC_ bool cli_credentials_set_ntlm_response(struct cli_credentials *cred,
const DATA_BLOB *lm_response,
const DATA_BLOB *nt_response,
enum credentials_obtained obtained)
{
if (obtained >= cred->password_obtained) {
cli_credentials_set_password(cred, NULL, obtained);
if (nt_response) {
cred->nt_response = data_blob_talloc(cred, nt_response->data, nt_response->length);
talloc_steal(cred, cred->nt_response.data);
}
if (nt_response) {
cred->lm_response = data_blob_talloc(cred, lm_response->data, lm_response->length);
}
return true;
}
return false;
}
|
