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
|
/*
Unix SMB/CIFS implementation.
Copyright (C) Andrew Tridgell 1992-2001
Copyright (C) Andrew Bartlett 2002
Copyright (C) Rafal Szczesniak 2002
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/>.
*/
/* the Samba secrets database stores any generated, private information
such as the local SID and machine trust password */
#include "includes.h"
#include "secrets.h"
#include "param/param.h"
#include "system/filesys.h"
#include "tdb_wrap.h"
#include "lib/ldb/include/ldb.h"
#include "../tdb/include/tdb.h"
#include "../lib/util/util_tdb.h"
#include "../lib/util/util_ldb.h"
#include "librpc/gen_ndr/ndr_security.h"
#include "dsdb/samdb/samdb.h"
#include "dsdb/common/util.h"
#include "dsdb/common/proto.h"
/**
* Use a TDB to store an incrementing random seed.
*
* Initialised to the current pid, the very first time Samba starts,
* and incremented by one each time it is needed.
*
* @note Not called by systems with a working /dev/urandom.
*/
static void get_rand_seed(struct tdb_wrap *secretsdb, int *new_seed)
{
*new_seed = getpid();
if (secretsdb != NULL) {
tdb_change_int32_atomic(secretsdb->tdb, "INFO/random_seed", new_seed, 1);
}
}
/**
* open up the secrets database
*/
struct tdb_wrap *secrets_init(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx)
{
char *fname;
uint8_t dummy;
struct tdb_wrap *tdb;
fname = private_path(mem_ctx, lp_ctx, "secrets.tdb");
tdb = tdb_wrap_open(mem_ctx, fname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600);
if (!tdb) {
DEBUG(0,("Failed to open %s\n", fname));
talloc_free(fname);
return NULL;
}
talloc_free(fname);
/**
* Set a reseed function for the crypto random generator
*
* This avoids a problem where systems without /dev/urandom
* could send the same challenge to multiple clients
*/
set_rand_reseed_callback((void (*) (void *, int *))get_rand_seed, tdb);
/* Ensure that the reseed is done now, while we are root, etc */
generate_random_buffer(&dummy, sizeof(dummy));
return tdb;
}
/**
connect to the secrets ldb
*/
struct ldb_context *secrets_db_connect(TALLOC_CTX *mem_ctx,
struct tevent_context *ev_ctx,
struct loadparm_context *lp_ctx)
{
char *path;
const char *url;
struct ldb_context *ldb;
url = lp_secrets_url(lp_ctx);
if (!url || !url[0]) {
return NULL;
}
path = private_path(mem_ctx, lp_ctx, url);
if (!path) {
return NULL;
}
/* Secrets.ldb *must* always be local. If we call for a
* system_session() we will recurse */
ldb = ldb_init(mem_ctx, ev_ctx);
if (!ldb) {
talloc_free(path);
return NULL;
}
ldb_set_modules_dir(ldb,
talloc_asprintf(ldb, "%s/ldb", lp_modulesdir(lp_ctx)));
if (ldb_connect(ldb, path, 0, NULL) != 0) {
talloc_free(path);
return NULL;
}
/* the update_keytab module relies on this being setup */
if (ldb_set_opaque(ldb, "loadparm", lp_ctx) != LDB_SUCCESS) {
talloc_free(path);
talloc_free(ldb);
return NULL;
}
talloc_free(path);
return ldb;
}
/**
* Retrieve the domain SID from the secrets database.
* @return pointer to a SID object if the SID could be obtained, NULL otherwise
*/
struct dom_sid *secrets_get_domain_sid(TALLOC_CTX *mem_ctx,
struct tevent_context *ev_ctx,
struct loadparm_context *lp_ctx,
const char *domain,
char **errstring)
{
struct ldb_context *ldb;
struct ldb_message *msg;
int ldb_ret;
const char *attrs[] = { "objectSid", NULL };
struct dom_sid *result = NULL;
const struct ldb_val *v;
enum ndr_err_code ndr_err;
*errstring = NULL;
ldb = secrets_db_connect(mem_ctx, ev_ctx, lp_ctx);
if (ldb == NULL) {
DEBUG(5, ("secrets_db_connect failed\n"));
return NULL;
}
ldb_ret = dsdb_search_one(ldb, ldb, &msg,
ldb_dn_new(mem_ctx, ldb, SECRETS_PRIMARY_DOMAIN_DN),
LDB_SCOPE_ONELEVEL,
attrs, 0, SECRETS_PRIMARY_DOMAIN_FILTER, domain);
if (ldb_ret != LDB_SUCCESS) {
*errstring = talloc_asprintf(mem_ctx, "Failed to find record for %s in %s: %s: %s",
domain, (char *) ldb_get_opaque(ldb, "ldb_url"),
ldb_strerror(ldb_ret), ldb_errstring(ldb));
return NULL;
}
v = ldb_msg_find_ldb_val(msg, "objectSid");
if (v == NULL) {
*errstring = talloc_asprintf(mem_ctx, "Failed to find a SID on record for %s in %s",
domain, (char *) ldb_get_opaque(ldb, "ldb_url"));
return NULL;
}
result = talloc(mem_ctx, struct dom_sid);
if (result == NULL) {
talloc_free(ldb);
return NULL;
}
ndr_err = ndr_pull_struct_blob(v, result, NULL, result,
(ndr_pull_flags_fn_t)ndr_pull_dom_sid);
if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
*errstring = talloc_asprintf(mem_ctx, "Failed to parse SID on record for %s in %s",
domain, (char *) ldb_get_opaque(ldb, "ldb_url"));
talloc_free(result);
talloc_free(ldb);
return NULL;
}
return result;
}
|
