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
|
/*
* (C) 2010-2015 by Holger Hans Peter Freyther <zecke@selfish.org>
* (C) 2010-2012 by On-Waves
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <openbsc/bsc_nat.h>
#include <openbsc/bsc_nat_sccp.h>
#include <openbsc/bsc_msg_filter.h>
#include <openbsc/debug.h>
#include <osmocom/gsm/gsm0808.h>
#include <osmocom/gsm/protocol/gsm_08_08.h>
#include <osmocom/gsm/protocol/gsm_04_11.h>
#include <osmocom/sccp/sccp.h>
/* Filter out CR data... */
int bsc_nat_filter_sccp_cr(struct bsc_connection *bsc, struct msgb *msg,
struct bsc_nat_parsed *parsed, int *con_type,
char **imsi, struct bsc_filter_reject_cause *cause)
{
struct bsc_filter_request req;
struct tlv_parsed tp;
struct gsm48_hdr *hdr48;
int hdr48_len;
int len;
*con_type = FLT_CON_TYPE_NONE;
cause->cm_reject_cause = GSM48_REJECT_PLMN_NOT_ALLOWED;
cause->lu_reject_cause = GSM48_REJECT_PLMN_NOT_ALLOWED;
*imsi = NULL;
if (parsed->gsm_type != BSS_MAP_MSG_COMPLETE_LAYER_3) {
LOGP(DNAT, LOGL_ERROR,
"Rejecting CR message due wrong GSM Type %d\n", parsed->gsm_type);
return -1;
}
/* the parsed has had some basic l3 length check */
len = msg->l3h[1];
if (msgb_l3len(msg) - 3 < len) {
LOGP(DNAT, LOGL_ERROR,
"The CR Data has not enough space...\n");
return -1;
}
msg->l4h = &msg->l3h[3];
len -= 1;
tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l4h, len, 0, 0);
if (!TLVP_PRESENT(&tp, GSM0808_IE_LAYER_3_INFORMATION)) {
LOGP(DNAT, LOGL_ERROR, "CR Data does not contain layer3 information.\n");
return -1;
}
hdr48_len = TLVP_LEN(&tp, GSM0808_IE_LAYER_3_INFORMATION);
if (hdr48_len < sizeof(*hdr48)) {
LOGP(DNAT, LOGL_ERROR, "GSM48 header does not fit.\n");
return -1;
}
hdr48 = (struct gsm48_hdr *) TLVP_VAL(&tp, GSM0808_IE_LAYER_3_INFORMATION);
req.ctx = bsc;
req.black_list = &bsc->nat->imsi_black_list;
req.access_lists = &bsc->nat->access_lists;
req.local_lst_name = bsc->cfg->acc_lst_name;
req.global_lst_name = bsc->nat->acc_lst_name;
req.bsc_nr = bsc->cfg->nr;
return bsc_msg_filter_initial(hdr48, hdr48_len, &req, con_type, imsi, cause);
}
int bsc_nat_filter_dt(struct bsc_connection *bsc, struct msgb *msg,
struct nat_sccp_connection *con, struct bsc_nat_parsed *parsed,
struct bsc_filter_reject_cause *cause)
{
uint32_t len;
struct gsm48_hdr *hdr48;
struct bsc_filter_request req;
cause->cm_reject_cause = GSM48_REJECT_PLMN_NOT_ALLOWED;
cause->lu_reject_cause = GSM48_REJECT_PLMN_NOT_ALLOWED;
if (con->filter_state.imsi_checked)
return 0;
/* only care about DTAP messages */
if (parsed->bssap != BSSAP_MSG_DTAP)
return 0;
hdr48 = bsc_unpack_dtap(parsed, msg, &len);
if (!hdr48)
return -1;
req.ctx = bsc;
req.black_list = &bsc->nat->imsi_black_list;
req.access_lists = &bsc->nat->access_lists;
req.local_lst_name = bsc->cfg->acc_lst_name;
req.global_lst_name = bsc->nat->acc_lst_name;
req.bsc_nr = bsc->cfg->nr;
return bsc_msg_filter_data(hdr48, len, &req, &con->filter_state, cause);
}
|
