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
|
/* Code to manage MSC subscriber connections over IuCS interface */
/*
* (C) 2016,2017 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
*
* Author: Neels Hofmeyr <nhofmeyr@sysmocom.de>
*
* 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 <inttypes.h>
#include <osmocom/core/logging.h>
#include <openbsc/debug.h>
#include <openbsc/gsm_data.h>
#include <openbsc/iu.h>
#include <openbsc/gsm_subscriber.h>
#include <openbsc/osmo_msc.h>
#include <openbsc/vlr.h>
/* For A-interface see libbsc/bsc_api.c subscr_con_allocate() */
static struct gsm_subscriber_connection *subscr_conn_allocate_iu(struct gsm_network *network,
struct ue_conn_ctx *ue,
uint16_t lac)
{
struct gsm_subscriber_connection *conn;
DEBUGP(DIUCS, "Allocating IuCS subscriber conn: lac %d, conn_id %" PRIx32 "\n",
lac, ue->conn_id);
conn = talloc_zero(network, struct gsm_subscriber_connection);
if (!conn)
return NULL;
conn->network = network;
conn->via_ran = RAN_UTRAN_IU;
conn->iu.ue_ctx = ue;
conn->iu.ue_ctx->rab_assign_addr_enc = network->iu.rab_assign_addr_enc;
conn->lac = lac;
llist_add_tail(&conn->entry, &network->subscr_conns);
return conn;
}
static int same_ue_conn(struct ue_conn_ctx *a, struct ue_conn_ctx *b)
{
if (a == b)
return 1;
return (a->conn_id == b->conn_id);
}
static inline void log_subscribers(struct gsm_network *network)
{
if (!log_check_level(DIUCS, LOGL_DEBUG))
return;
struct gsm_subscriber_connection *conn;
int i = 0;
llist_for_each_entry(conn, &network->subscr_conns, entry) {
DEBUGP(DIUCS, "%3d: %s", i, vlr_subscr_name(conn->vsub));
switch (conn->via_ran) {
case RAN_UTRAN_IU:
DEBUGPC(DIUCS, " Iu");
if (conn->iu.ue_ctx) {
DEBUGPC(DIUCS, " conn_id %d",
conn->iu.ue_ctx->conn_id
);
}
break;
case RAN_GERAN_A:
DEBUGPC(DIUCS, " A");
/* TODO log A-interface connection details */
break;
case RAN_UNKNOWN:
DEBUGPC(DIUCS, " ?");
break;
default:
DEBUGPC(DIUCS, " invalid");
break;
}
DEBUGPC(DIUCS, "\n");
i++;
}
DEBUGP(DIUCS, "subscribers registered: %d\n", i);
}
/* Return an existing IuCS subscriber connection record for the given
* connection IDs, or return NULL if not found. */
struct gsm_subscriber_connection *subscr_conn_lookup_iu(
struct gsm_network *network,
struct ue_conn_ctx *ue)
{
struct gsm_subscriber_connection *conn;
DEBUGP(DIUCS, "Looking for IuCS subscriber: conn_id %" PRIx32 "\n",
ue->conn_id);
log_subscribers(network);
llist_for_each_entry(conn, &network->subscr_conns, entry) {
if (conn->via_ran != RAN_UTRAN_IU)
continue;
if (!same_ue_conn(conn->iu.ue_ctx, ue))
continue;
DEBUGP(DIUCS, "Found IuCS subscriber for conn_id %" PRIx32 "\n",
ue->conn_id);
return conn;
}
DEBUGP(DIUCS, "No IuCS subscriber found for conn_id %" PRIx32 "\n",
ue->conn_id);
return NULL;
}
/* Receive MM/CC/... message from IuCS (SCCP user SAP).
* msg->dst must reference a struct ue_conn_ctx, which identifies the peer that
* sent the msg.
*
* For A-interface see libbsc/bsc_api.c gsm0408_rcvmsg(). */
int gsm0408_rcvmsg_iucs(struct gsm_network *network, struct msgb *msg,
uint16_t *lac)
{
int rc;
struct ue_conn_ctx *ue_ctx;
struct gsm_subscriber_connection *conn;
ue_ctx = (struct ue_conn_ctx*)msg->dst;
/* TODO: are there message types that could allow us to skip this
* search? */
conn = subscr_conn_lookup_iu(network, ue_ctx);
if (conn && lac && (conn->lac != *lac)) {
LOGP(DIUCS, LOGL_ERROR, "IuCS subscriber has changed LAC"
" within the same connection, discarding connection:"
" %s from LAC %d to %d\n",
vlr_subscr_name(conn->vsub), conn->lac, *lac);
/* Deallocate conn with previous LAC */
msc_subscr_conn_close(conn, GSM_CAUSE_INV_MAND_INFO);
/* At this point we could be tolerant and allocate a new
* connection, but changing the LAC within the same connection
* is shifty. Rather cancel everything. */
return -1;
}
if (conn) {
/* Make sure we don't receive RR over IuCS; otherwise all
* messages handled by gsm0408_dispatch() are of interest (CC,
* MM, SMS, NS_SS, maybe even MM_GPRS and SM_GPRS). */
struct gsm48_hdr *gh = msgb_l3(msg);
uint8_t pdisc = gh->proto_discr & 0x0f;
OSMO_ASSERT(pdisc != GSM48_PDISC_RR);
msc_dtap(conn, ue_ctx->conn_id, msg);
rc = 0;
} else {
/* allocate a new connection */
if (!lac) {
LOGP(DIUCS, LOGL_ERROR, "New IuCS subscriber"
" but no LAC available. Expecting an InitialUE"
" message containing a LAI IE."
" Dropping connection.\n");
return -1;
}
conn = subscr_conn_allocate_iu(network, ue_ctx, *lac);
if (!conn)
abort();
/* ownership of conn hereby goes to the MSC: */
rc = msc_compl_l3(conn, msg, 0);
}
return rc;
}
|
