diff options
Diffstat (limited to 'src/osmo-bsc/osmo_bsc_mgcp.c')
-rw-r--r-- | src/osmo-bsc/osmo_bsc_mgcp.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/src/osmo-bsc/osmo_bsc_mgcp.c b/src/osmo-bsc/osmo_bsc_mgcp.c new file mode 100644 index 000000000..d984125ab --- /dev/null +++ b/src/osmo-bsc/osmo_bsc_mgcp.c @@ -0,0 +1,91 @@ +/* + * 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 enouhg 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 & BSC_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); + 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); +} |