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/*
* (C) 2010 by Holger Hans Peter Freyther <zecke@selfish.org>
* (C) 2010 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 General Public License as published by
* the Free Software Foundation; either version 2 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, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <openbsc/bsc_nat.h>
#include <openbsc/gsm_data.h>
#include <openbsc/bssap.h>
#include <openbsc/debug.h>
#include <openbsc/mgcp.h>
#include <openbsc/mgcp_internal.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <unistd.h>
int bsc_mgcp_assign(struct sccp_connections *con, struct msgb *msg)
{
struct tlv_parsed tp;
u_int16_t cic;
u_int8_t timeslot;
u_int8_t multiplex;
if (!msg->l3h) {
LOGP(DNAT, LOGL_ERROR, "Assignment message should have l3h pointer.\n");
return -1;
}
if (msgb_l3len(msg) < 3) {
LOGP(DNAT, LOGL_ERROR, "Assignment message has not enough space for GSM0808.\n");
return -1;
}
tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 3, msgb_l3len(msg) - 3, 0, 0);
if (!TLVP_PRESENT(&tp, GSM0808_IE_CIRCUIT_IDENTITY_CODE)) {
LOGP(DNAT, LOGL_ERROR, "Circuit identity code not found in assignment message.\n");
return -1;
}
cic = ntohs(*(u_int16_t *)TLVP_VAL(&tp, GSM0808_IE_CIRCUIT_IDENTITY_CODE));
timeslot = cic & 0x1f;
multiplex = (cic & ~0x1f) >> 5;
con->msc_timeslot = (32 * multiplex) + timeslot;
con->bsc_timeslot = con->msc_timeslot;
return 0;
}
void bsc_mgcp_clear(struct sccp_connections *con)
{
con->msc_timeslot = -1;
con->bsc_timeslot = -1;
}
void bsc_mgcp_free_endpoints(struct bsc_nat *nat)
{
int i;
for (i = 1; i < nat->mgcp_cfg->number_endpoints; ++i)
mgcp_free_endp(&nat->mgcp_cfg->endpoints[i]);
}
struct bsc_connection *bsc_mgcp_find_con(struct bsc_nat *nat, int endpoint)
{
struct sccp_connections *sccp;
llist_for_each_entry(sccp, &nat->sccp_connections, list_entry) {
if (sccp->msc_timeslot == -1)
continue;
if (mgcp_timeslot_to_endpoint(0, sccp->msc_timeslot) != endpoint)
continue;
return sccp->bsc;
}
LOGP(DMGCP, LOGL_ERROR, "Failed to find the connection.\n");
return NULL;
}
static int mgcp_do_read(struct bsc_fd *fd)
{
struct bsc_nat *nat;
struct msgb *msg, *resp;
int rc;
msg = msgb_alloc(4096, "MGCP GW Read");
if (!msg) {
LOGP(DMGCP, LOGL_ERROR, "Failed to create buffer.\n");
return -1;
}
rc = read(fd->fd, msg->data, msg->data_len);
if (rc <= 0) {
LOGP(DMGCP, LOGL_ERROR, "Failed to read errno: %d\n", errno);
msgb_free(msg);
return -1;
}
nat = fd->data;
msg->l2h = msgb_put(msg, rc);
resp = mgcp_handle_message(nat->mgcp_cfg, msg);
msgb_free(msg);
/* we do have a direct answer... e.g. AUEP */
if (resp) {
if (write_queue_enqueue(&nat->mgcp_queue, resp) != 0) {
LOGP(DMGCP, LOGL_ERROR, "Failed to enqueue msg.\n");
msgb_free(resp);
}
}
return 0;
}
static int mgcp_do_write(struct bsc_fd *bfd, struct msgb *msg)
{
int rc;
rc = write(bfd->fd, msg->data, msg->len);
if (rc != msg->len) {
LOGP(DMGCP, LOGL_ERROR, "Failed to write msg to MGCP CallAgent.\n");
return -1;
}
return rc;
}
int bsc_mgcp_init(struct bsc_nat *nat)
{
int on;
struct sockaddr_in addr;
if (!nat->mgcp_cfg->call_agent_addr) {
LOGP(DMGCP, LOGL_ERROR, "The BSC nat requires the call agent ip to be set.\n");
return -1;
}
nat->mgcp_queue.bfd.fd = socket(AF_INET, SOCK_DGRAM, 0);
if (nat->mgcp_queue.bfd.fd < 0) {
LOGP(DMGCP, LOGL_ERROR, "Failed to create MGCP socket. errno: %d\n", errno);
return -1;
}
on = 1;
setsockopt(nat->mgcp_queue.bfd.fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
addr.sin_family = AF_INET;
addr.sin_port = htons(nat->mgcp_cfg->source_port);
inet_aton(nat->mgcp_cfg->source_addr, &addr.sin_addr);
if (bind(nat->mgcp_queue.bfd.fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
LOGP(DMGCP, LOGL_ERROR, "Failed to bind. errno: %d\n", errno);
close(nat->mgcp_queue.bfd.fd);
nat->mgcp_queue.bfd.fd = -1;
return -1;
}
addr.sin_port = htons(2727);
inet_aton(nat->mgcp_cfg->call_agent_addr, &addr.sin_addr);
if (connect(nat->mgcp_queue.bfd.fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
LOGP(DMGCP, LOGL_ERROR, "Failed to connect to: '%s'. errno: %d\n",
nat->mgcp_cfg->call_agent_addr, errno);
close(nat->mgcp_queue.bfd.fd);
nat->mgcp_queue.bfd.fd = -1;
return -1;
}
write_queue_init(&nat->mgcp_queue, 10);
nat->mgcp_queue.bfd.when = BSC_FD_READ;
nat->mgcp_queue.bfd.data = nat;
nat->mgcp_queue.read_cb = mgcp_do_read;
nat->mgcp_queue.write_cb = mgcp_do_write;
if (bsc_register_fd(&nat->mgcp_queue.bfd) != 0) {
LOGP(DMGCP, LOGL_ERROR, "Failed to register MGCP fd.\n");
close(nat->mgcp_queue.bfd.fd);
nat->mgcp_queue.bfd.fd = -1;
return -1;
}
return 0;
}
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