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
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
|
/*
Unix SMB/CIFS implementation.
SMB Transport encryption (sealing) code.
Copyright (C) Jeremy Allison 2007.
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 2 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, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "includes.h"
/******************************************************************************
Generic code for client and server.
Is encryption turned on ?
******************************************************************************/
BOOL common_encryption_on(struct smb_trans_enc_state *es)
{
return ((es != NULL) && es->enc_on);
}
/******************************************************************************
Generic code for client and server.
NTLM decrypt an incoming buffer.
******************************************************************************/
NTSTATUS common_ntlm_decrypt_buffer(NTLMSSP_STATE *ntlmssp_state, char *buf)
{
NTSTATUS status;
size_t orig_len = smb_len(buf);
size_t new_len = orig_len - NTLMSSP_SIG_SIZE;
DATA_BLOB sig;
if (orig_len < 8 + NTLMSSP_SIG_SIZE) {
return NT_STATUS_BUFFER_TOO_SMALL;
}
/* Save off the signature. */
sig = data_blob(buf+orig_len-NTLMSSP_SIG_SIZE, NTLMSSP_SIG_SIZE);
status = ntlmssp_unseal_packet(ntlmssp_state,
(unsigned char *)buf + 8, /* 4 byte len + 0xFF 'S' 'M' 'B' */
new_len - 8,
(unsigned char *)buf,
new_len,
&sig);
if (!NT_STATUS_IS_OK(status)) {
data_blob_free(&sig);
return status;
}
/* Reset the length. */
smb_setlen(buf, new_len);
return NT_STATUS_OK;
}
/******************************************************************************
Generic code for client and server.
NTLM encrypt an outgoing buffer. Return the encrypted pointer in ppbuf_out.
******************************************************************************/
NTSTATUS common_ntlm_encrypt_buffer(NTLMSSP_STATE *ntlmssp_state, char *buf, char **ppbuf_out)
{
NTSTATUS status;
char *buf_out;
size_t orig_len = smb_len(buf);
size_t new_len = orig_len + NTLMSSP_SIG_SIZE;
DATA_BLOB sig;
*ppbuf_out = NULL;
if (orig_len < 8) {
return NT_STATUS_BUFFER_TOO_SMALL;
}
/*
* We know smb_len can't return a value > 128k, so no int overflow
* check needed.
*/
/* Copy the original buffer. */
buf_out = SMB_XMALLOC_ARRAY(char, new_len);
memcpy(buf_out, buf, orig_len);
/* Last 16 bytes undefined here... */
smb_setlen(buf_out, new_len);
sig = data_blob(NULL, NTLMSSP_SIG_SIZE);
status = ntlmssp_seal_packet(ntlmssp_state,
(unsigned char *)buf_out + 8, /* 4 byte len + 0xFF 'S' 'M' 'B' */
orig_len - 8,
(unsigned char *)buf_out,
orig_len,
&sig);
if (!NT_STATUS_IS_OK(status)) {
data_blob_free(&sig);
SAFE_FREE(buf_out);
return status;
}
memcpy(buf_out+orig_len, sig.data, NTLMSSP_SIG_SIZE);
*ppbuf_out = buf_out;
return NT_STATUS_OK;
}
/******************************************************************************
Generic code for client and server.
gss-api decrypt an incoming buffer.
******************************************************************************/
#if defined(HAVE_GSSAPI_SUPPORT) && defined(HAVE_KRB5)
NTSTATUS common_gss_decrypt_buffer(gss_ctx_id_t context_handle, char *buf)
{
return NT_STATUS_NOT_SUPPORTED;
}
#endif
/******************************************************************************
Generic code for client and server.
gss-api encrypt an outgoing buffer. Return the alloced encrypted pointer in buf_out.
******************************************************************************/
#if defined(HAVE_GSSAPI_SUPPORT) && defined(HAVE_KRB5)
NTSTATUS common_gss_encrypt_buffer(gss_ctx_id_t context_handle, char *buf, char **buf_out)
{
return NT_STATUS_NOT_SUPPORTED;
}
#endif
/******************************************************************************
Generic code for client and server.
Encrypt an outgoing buffer. Return the alloced encrypted pointer in buf_out.
******************************************************************************/
NTSTATUS common_encrypt_buffer(struct smb_trans_enc_state *es, char *buffer, char **buf_out)
{
if (!common_encryption_on(es)) {
/* Not encrypting. */
*buf_out = buffer;
return NT_STATUS_OK;
}
if (es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
return common_ntlm_encrypt_buffer(es->ntlmssp_state, buffer, buf_out);
} else {
#if defined(HAVE_GSSAPI_SUPPORT) && defined(HAVE_KRB5)
return common_gss_encrypt_buffer(es->context_handle, buffer, buf_out);
#else
return NT_STATUS_NOT_SUPPORTED;
#endif
}
}
/******************************************************************************
Generic code for client and server.
Decrypt an incoming SMB buffer. Replaces the data within it.
New data must be less than or equal to the current length.
******************************************************************************/
NTSTATUS common_decrypt_buffer(struct smb_trans_enc_state *es, char *buf)
{
if (!common_encryption_on(es)) {
/* Not decrypting. */
return NT_STATUS_OK;
}
if (es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
return common_ntlm_decrypt_buffer(es->ntlmssp_state, buf);
} else {
#if defined(HAVE_GSSAPI_SUPPORT) && defined(HAVE_KRB5)
return common_gss_decrypt_buffer(es->context_handle, buf);
#else
return NT_STATUS_NOT_SUPPORTED;
#endif
}
}
/******************************************************************************
Shutdown an encryption state.
******************************************************************************/
void common_free_encryption_state(struct smb_trans_enc_state **pp_es)
{
struct smb_trans_enc_state *es = *pp_es;
if (es == NULL) {
return;
}
if (es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
if (es->ntlmssp_state) {
ntlmssp_end(&es->ntlmssp_state);
}
}
#if defined(HAVE_GSSAPI_SUPPORT) && defined(HAVE_KRB5)
if (es->smb_enc_type == SMB_TRANS_ENC_GSS) {
/* Free the gss context handle. */
}
#endif
SAFE_FREE(es);
*pp_es = NULL;
}
/******************************************************************************
Free an encryption-allocated buffer.
******************************************************************************/
void common_free_enc_buffer(struct smb_trans_enc_state *es, char *buf)
{
if (!common_encryption_on(es)) {
return;
}
if (es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
SAFE_FREE(buf);
return;
}
#if defined(HAVE_GSSAPI_SUPPORT) && defined(HAVE_KRB5)
/* gss-api free buffer.... */
#endif
}
/******************************************************************************
Client side encryption.
******************************************************************************/
/******************************************************************************
Is client encryption on ?
******************************************************************************/
BOOL cli_encryption_on(struct cli_state *cli)
{
return common_encryption_on(cli->trans_enc_state);
}
/******************************************************************************
Shutdown a client encryption state.
******************************************************************************/
void cli_free_encryption_context(struct cli_state *cli)
{
return common_free_encryption_state(&cli->trans_enc_state);
}
/******************************************************************************
Free an encryption-allocated buffer.
******************************************************************************/
void cli_free_enc_buffer(struct cli_state *cli, char *buf)
{
return common_free_enc_buffer(cli->trans_enc_state, buf);
}
/******************************************************************************
Decrypt an incoming buffer.
******************************************************************************/
NTSTATUS cli_decrypt_message(struct cli_state *cli)
{
return common_decrypt_buffer(cli->trans_enc_state, cli->inbuf);
}
/******************************************************************************
Encrypt an outgoing buffer. Return the encrypted pointer in buf_out.
******************************************************************************/
NTSTATUS cli_encrypt_message(struct cli_state *cli, char **buf_out)
{
return common_encrypt_buffer(cli->trans_enc_state, cli->outbuf, buf_out);
}
|
