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
|
/*
* SCCPlite MGCP handling
*
* (C) 2018 by Harald Welte <laforge@gnumonks.org>
* 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 <osmocom/bsc/bsc_msc_data.h>
#include <osmocom/bsc/osmo_bsc.h>
#include <osmocom/bsc/gsm_data.h>
#include <osmocom/bsc/debug.h>
#include <osmocom/gsm/ipa.h>
#include <osmocom/gsm/protocol/ipaccess.h>
#include <osmocom/bsc/osmo_bsc_sigtran.h>
#include <arpa/inet.h>
/* Determine MSC based on the ASP over which the message was received */
static struct bsc_msc_data *msc_from_asp(struct osmo_ss7_asp *asp)
{
int msc_nr;
/* this is rather ugly, as we of course have MTP-level routing between
* the local SCCP user (BSC) and the AS/ASPs. However, for the most simple
* SCCPlite case, there is a 1:1 mapping between ASP and AS, and using
* the libosmo-sigtran "simple client", the names are "as[p]-clnt-msc-%u",
* as set in osmo_bsc_sigtran_init() */
if (sscanf(asp->cfg.name, "asp-clnt-msc-%u", &msc_nr) != 1) {
LOGP(DMSC, LOGL_ERROR, "Cannot find to which MSC the ASP %s belongs\n", asp->cfg.name);
return NULL;
}
return osmo_msc_data_find(bsc_gsmnet, msc_nr);
}
/* We received an IPA-encapsulated MGCP message from a MSC. Transfers msg ownership. */
int bsc_sccplite_rx_mgcp(struct osmo_ss7_asp *asp, struct msgb *msg)
{
struct bsc_msc_data *msc;
int rc;
LOGP(DMSC, LOGL_NOTICE, "%s: Received IPA-encapsulated MGCP: %s\n", asp->cfg.name, msg->l2h);
msc = msc_from_asp(asp);
if (msc) {
/* we don't have a write queue here as we simply expect the socket buffers
* to be large enough to deal with whatever small/infrequent MGCP messages */
rc = send(msc->mgcp_ipa.ofd.fd, msgb_l2(msg), msgb_l2len(msg), 0);
} else
rc = 0;
msgb_free(msg);
return rc;
}
/* we received some data on the UDP proxy socket from the MGW. Pass it to MSC via IPA */
int bsc_sccplite_mgcp_proxy_cb(struct osmo_fd *ofd, unsigned int what)
{
struct bsc_msc_data *msc = ofd->data;
struct msgb *msg;
int rc;
if (!(what & OSMO_FD_READ))
return 0;
msg = msgb_alloc_headroom(1024, 16, "MGCP->IPA");
OSMO_ASSERT(msg);
rc = recv(ofd->fd, msg->data, msgb_tailroom(msg), 0);
if (rc <= 0) {
LOGP(DMSC, LOGL_ERROR, "error receiving data from MGCP<->IPA proxy UDP socket: "
"%s\n", strerror(errno));
msgb_free(msg);
return rc;
}
msg->l2h = msgb_put(msg, rc);
msg->l2h[rc] = '\0';
LOGP(DMSC, LOGL_NOTICE, "Received MGCP on UDP proxy socket: %s\n", msg->l2h);
ipa_prepend_header(msg, IPAC_PROTO_MGCP_OLD);
return bsc_sccplite_msc_send(msc, msg);
}
|
