/* OsmoMSC - Circuit-Switched Core Network (MSC+VLR+SMSC) implementation
 */

/* (C) 2016-2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
 * All Rights Reserved
 *
 * Based on OsmoNITB:
 * (C) 2008-2010 by Harald Welte <laforge@gnumonks.org>
 * (C) 2009-2012 by Holger Hans Peter Freyther <zecke@selfish.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 <stdbool.h>
#include <unistd.h>
#include <stdio.h>
#include <time.h>
#include <errno.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/stat.h>

#define _GNU_SOURCE
#include <getopt.h>

/* build switches from the configure script */
#include "config.h"

#include <osmocom/msc/db.h>
#include <osmocom/core/application.h>
#include <osmocom/core/select.h>
#include <osmocom/core/stats.h>
#include <osmocom/msc/debug.h>
#include <osmocom/abis/abis.h>
#include <osmocom/abis/e1_input.h>
#include <osmocom/core/talloc.h>
#include <osmocom/msc/signal.h>
#include <osmocom/msc/sms_queue.h>
#include <osmocom/vty/telnet_interface.h>
#include <osmocom/vty/ports.h>
#include <osmocom/vty/logging.h>
#include <osmocom/vty/misc.h>
#include <osmocom/vty/cpu_sched_vty.h>
#include <osmocom/msc/vty.h>
#include <osmocom/msc/mncc.h>
#include <osmocom/msc/rrlp.h>
#include <osmocom/ctrl/control_if.h>
#include <osmocom/ctrl/control_vty.h>
#include <osmocom/ctrl/ports.h>
#include <osmocom/smpp/smpp.h>
#include <osmocom/sigtran/osmo_ss7.h>
#include <osmocom/mgcp_client/mgcp_client.h>
#include <osmocom/msc/sgs_iface.h>
#include <osmocom/msc/sgs_server.h>
#include <osmocom/msc/ran_infra.h>
#include <osmocom/msc/ran_peer.h>
#include <osmocom/msc/ran_msg_a.h>
#include <osmocom/msc/msub.h>
#include <osmocom/msc/call_leg.h>
#include <osmocom/msc/msc_ho.h>
#include <osmocom/gsupclient/gsup_client_mux.h>
#include <osmocom/msc/e_link.h>
#include <osmocom/msc/mncc_call.h>

#ifdef BUILD_IU
#include <asn1c/asn_internal.h>
#endif

static const char * const osmomsc_copyright =
	"OsmoMSC - Osmocom Circuit-Switched Core Network implementation\r\n"
	"Copyright (C) 2016 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>\r\n"
	"Based on OsmoNITB:\r\n"
	"  (C) 2008-2010 by Harald Welte <laforge@gnumonks.org>\r\n"
	"  (C) 2009-2012 by Holger Hans Peter Freyther <zecke@selfish.org>\r\n"
	"Contributions by Daniel Willmann, Jan Lübbe, Stefan Schmidt\r\n"
	"Dieter Spaar, Andreas Eversberg, Sylvain Munaut, Neels Hofmeyr\r\n\r\n"
	"License AGPLv3+: GNU AGPL version 3 or later <http://gnu.org/licenses/agpl-3.0.html>\r\n"
	"This is free software: you are free to change and redistribute it.\r\n"
	"There is NO WARRANTY, to the extent permitted by law.\r\n";

void *tall_msc_ctx = NULL;

/* satisfy deps from libbsc legacy.
   TODO double check these */
void *tall_map_ctx = NULL;
/* end deps from libbsc legacy. */

static struct {
	const char *config_file;
	int daemonize;
	const char *mncc_sock_path;
} msc_cmdline_config = {
	.config_file = "osmo-msc.cfg",
};

/* timer to store statistics */
#define EXPIRE_INTERVAL		10, 0

static int quit = 0;

static void print_usage()
{
	printf("Usage: osmo-msc\n");
}

static void print_help()
{
	printf("Some useful options:\n");
	printf("  -h --help                  This text.\n");
	printf("  -d option --debug=DCC:DMM:DRR:  Enable debugging.\n");
	printf("  -D --daemonize             Fork the process into a background daemon.\n");
	printf("  -c --config-file filename  The config file to use.\n");
	printf("  -s --disable-color\n");
	printf("  -T --timestamp             Prefix every log line with a timestamp.\n");
	printf("  -V --version               Print the version of OsmoMSC.\n");
	printf("  -e --log-level number      Set a global loglevel.\n");

	printf("\nVTY reference generation:\n");
	printf("     --vty-ref-mode MODE     VTY reference generation mode (e.g. 'expert').\n");
	printf("     --vty-ref-xml           Generate the VTY reference XML output and exit.\n");
}

static void handle_long_options(const char *prog_name, const int long_option)
{
	static int vty_ref_mode = VTY_REF_GEN_MODE_DEFAULT;

	switch (long_option) {
	case 1:
		vty_ref_mode = get_string_value(vty_ref_gen_mode_names, optarg);
		if (vty_ref_mode < 0) {
			fprintf(stderr, "%s: Unknown VTY reference generation "
				"mode '%s'\n", prog_name, optarg);
			exit(2);
		}
		break;
	case 2:
		fprintf(stderr, "Generating the VTY reference in mode '%s' (%s)\n",
			get_value_string(vty_ref_gen_mode_names, vty_ref_mode),
			get_value_string(vty_ref_gen_mode_desc, vty_ref_mode));
		vty_dump_xml_ref_mode(stdout, (enum vty_ref_gen_mode) vty_ref_mode);
		exit(0);
	default:
		fprintf(stderr, "%s: error parsing cmdline options\n", prog_name);
		exit(2);
	}
}

static void handle_options(int argc, char **argv)
{
	while (1) {
		int option_index = 0, c;
		static int long_option = 0;
		static struct option long_options[] = {
			{"help", 0, 0, 'h'},
			{"debug", 1, 0, 'd'},
			{"daemonize", 0, 0, 'D'},
			{"config-file", 1, 0, 'c'},
			{"disable-color", 0, 0, 's'},
			{"database", 1, 0, 'l'}, /* deprecated */
			{"timestamp", 0, 0, 'T'},
			{"version", 0, 0, 'V' },
			{"log-level", 1, 0, 'e'},
			{"mncc-sock-path", 1, 0, 'M'}, /* deprecated */
			{"no-dbcounter", 0, 0, 'C'}, /* deprecated */
			{"vty-ref-mode", 1, &long_option, 1},
			{"vty-ref-xml", 0, &long_option, 2},
			{0, 0, 0, 0}
		};

		c = getopt_long(argc, argv, "hd:Dsl:TVc:e:CM:",
				long_options, &option_index);
		if (c == -1)
			break;

		switch (c) {
		case 'h':
			print_usage();
			print_help();
			exit(0);
		case 0:
			handle_long_options(argv[0], long_option);
			break;
		case 's':
			log_set_use_color(osmo_stderr_target, 0);
			break;
		case 'd':
			log_parse_category_mask(osmo_stderr_target, optarg);
			break;
		case 'D':
			msc_cmdline_config.daemonize = 1;
			break;
		case 'l':
			fprintf(stderr, "Command line argument '-%c' is deprecated, use VTY "
				"parameter 'smsc' / 'database %s' instead.\n", c, optarg);
			exit(2);
			break;
		case 'c':
			msc_cmdline_config.config_file = optarg;
			break;
		case 'T':
			log_set_print_timestamp(osmo_stderr_target, 1);
			break;
		case 'e':
			log_set_log_level(osmo_stderr_target, atoi(optarg));
			break;
		case 'M':
			msc_cmdline_config.mncc_sock_path = optarg;
			fprintf(stderr, "Command line argument '-%c' is deprecated, use VTY "
				"parameter 'msc' / 'mncc external %s' instead.\n", c, optarg);
			break;
		case 'C':
			fprintf(stderr, "-C is deprecated and does nothing.");
			break;
		case 'V':
			print_version(1);
			exit(0);
			break;
		default:
			/* catch unknown options *as well as* missing arguments. */
			fprintf(stderr, "Error in command line options. Exiting.\n");
			exit(-1);
		}
	}

	if (argc > optind) {
		fprintf(stderr, "Unsupported positional arguments on command line\n");
		exit(2);
	}
}

static struct gsm_network *msc_network_alloc(void *ctx,
					     mncc_recv_cb_t mncc_recv)
{
	struct gsm_network *net = gsm_network_init(ctx, mncc_recv);
	if (!net)
		return NULL;

	net->name_long = talloc_strdup(net, "OsmoMSC");
	net->name_short = talloc_strdup(net, "OsmoMSC");

	net->gsup_server_addr_str = talloc_strdup(net,
						  MSC_HLR_REMOTE_IP_DEFAULT);
	net->gsup_server_port = MSC_HLR_REMOTE_PORT_DEFAULT;

	net->mgw.mgw_pool = mgcp_client_pool_alloc(net);
	net->mgw.conf = mgcp_client_conf_alloc(net);
	net->call_waiting = true;
	net->lcls_permitted = false;

	net->mgw.tdefs = g_mgw_tdefs;
	osmo_tdefs_reset(net->mgw.tdefs);
	net->sms_queue_cfg = sms_queue_cfg_alloc(ctx);

	return net;
}

void msc_network_shutdown(struct gsm_network *net)
{
	/* nothing here yet */
}

static struct gsm_network *msc_network = NULL;

extern void *tall_vty_ctx;
static void signal_handler(int signum)
{
	fprintf(stdout, "signal %u received\n", signum);

	switch (signum) {
	case SIGINT:
	case SIGTERM:
		LOGP(DMSC, LOGL_NOTICE, "Terminating due to signal %d\n", signum);
		quit++;
		break;
	case SIGABRT:
		osmo_generate_backtrace();
		/* in case of abort, we want to obtain a talloc report and
		 * then run default SIGABRT handler, who will generate coredump
		 * and abort the process. abort() should do this for us after we
		 * return, but program wouldn't exit if an external SIGABRT is
		 * received.
		 */
		talloc_report(tall_vty_ctx, stderr);
		talloc_report_full(tall_msc_ctx, stderr);
		signal(SIGABRT, SIG_DFL);
		raise(SIGABRT);
		break;
	case SIGUSR1:
		talloc_report(tall_vty_ctx, stderr);
		talloc_report_full(tall_msc_ctx, stderr);
		break;
	case SIGUSR2:
		talloc_report_full(tall_vty_ctx, stderr);
		break;
	default:
		break;
	}
}

static int msc_vty_go_parent(struct vty *vty)
{
	switch (vty->node) {
	case GSMNET_NODE:
		vty->node = CONFIG_NODE;
		vty->index = NULL;
		break;
	case MGW_NODE:
		OSMO_ASSERT(msc_network != NULL);
		vty->node = GSMNET_NODE;
		vty->index = msc_network;
		break;
	case SMPP_ESME_NODE:
		vty->node = SMPP_NODE;
		vty->index = NULL;
		break;
	case SMPP_NODE:
	case MSC_NODE:
	case MNCC_INT_NODE:
	case ASCI_NODE:
		vty->node = CONFIG_NODE;
		vty->index = NULL;
		break;
	case GCR_NODE:
		vty->node = ASCI_NODE;
		vty->index = NULL;
		break;
	case VGC_NODE:
	case VBC_NODE:
		vty->node = GCR_NODE;
		vty->index = NULL;
		break;
	case SUBSCR_NODE:
		vty->node = ENABLE_NODE;
		vty->index = NULL;
		break;
	default:
		osmo_ss7_vty_go_parent(vty);
	}

	return vty->node;
}

static struct vty_app_info msc_vty_info = {
	.name		= "OsmoMSC",
	.version	= PACKAGE_VERSION,
	.go_parent_cb	= msc_vty_go_parent,
};

#define DEFAULT_M3UA_LOCAL_IP "localhost"
#define DEFAULT_M3UA_REMOTE_IP "localhost"
#define DEFAULT_PC "0.23.1"

static struct osmo_sccp_instance *sccp_setup(void *ctx, uint32_t cs7_instance,
					     const char *label, const char *default_pc_str)
{
	int default_pc = osmo_ss7_pointcode_parse(NULL, default_pc_str);
	if (default_pc < 0)
		return NULL;

	return osmo_sccp_simple_client_on_ss7_id(ctx, cs7_instance, label, default_pc,
						 OSMO_SS7_ASP_PROT_M3UA,
						 0, DEFAULT_M3UA_LOCAL_IP, /* local: use arbitrary port and 0.0.0.0. */
						 0, /* remote: use protocol default port */
						 DEFAULT_M3UA_REMOTE_IP);
	/* Note: If a differing remote IP is to be used, it was already entered in the vty config at
	 * 'cs7' / 'asp' / 'remote-ip', and this default remote IP has no effect.
	 * Similarly, 'cs7' / 'listen' can specify the local IP address. */
}

static int ss7_setup(void *ctx, struct osmo_sccp_instance **sccp_a, struct osmo_sccp_instance **sccp_iu)
{
	uint32_t i_a = msc_network->a.cs7_instance;
	uint32_t i_iu = msc_network->iu.cs7_instance;

	const char *name_a = "OsmoMSC-A";
	const char *name_iu = NULL;

#if BUILD_IU
	if (i_a == i_iu)
		name_a = name_iu = "OsmoMSC-A-Iu";
	else
		name_iu = "OsmoMSC-Iu";
#endif

	*sccp_a = sccp_setup(ctx, i_a, name_a, DEFAULT_PC);
	if (!*sccp_a)
		return -EINVAL;

	if (!name_iu) {
		*sccp_iu = NULL;
		return 0;
	}

	if (i_a == i_iu) {
		*sccp_iu = *sccp_a;
		return 0;
	}

	*sccp_iu = sccp_setup(ctx, i_iu, name_iu, DEFAULT_PC);
	if (!*sccp_iu)
		return -EINVAL;

	return 0;
}

static const struct log_info_cat msc_default_categories[] = {
	[DRLL] = {
		.name = "DRLL",
		.description = "A-bis Radio Link Layer (RLL)",
		.color = "\033[1;31m",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DCC] = {
		.name = "DCC",
		.description = "Layer3 Call Control (CC)",
		.color = "\033[1;32m",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DBCC] = {
		.name = "DBCC",
		.description = "Layer3 Broadcast Call Control (BCC)",
		.color = "\033[1;32m",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DGCC] = {
		.name = "DGCC",
		.description = "Layer3 Group Call Control (GCC)",
		.color = "\033[1;32m",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DMM] = {
		.name = "DMM",
		.description = "Layer3 Mobility Management (MM)",
		.color = "\033[1;33m",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DRR] = {
		.name = "DRR",
		.description = "Layer3 Radio Resource (RR)",
		.color = "\033[1;34m",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DMNCC] = {
		.name = "DMNCC",
		.description = "MNCC API for Call Control application",
		.color = "\033[1;39m",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DPAG]	= {
		.name = "DPAG",
		.description = "Paging Subsystem",
		.color = "\033[1;38m",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DMSC] = {
		.name = "DMSC",
		.description = "Mobile Switching Center",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DMGCP] = {
		.name = "DMGCP",
		.description = "Media Gateway Control Protocol",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DHO] = {
		.name = "DHO",
		.description = "Hand-Over",
		.color = "\033[1;38m",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DDB] = {
		.name = "DDB",
		.description = "Database Layer",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DREF] = {
		.name = "DREF",
		.description = "Reference Counting",
		.enabled = 0, .loglevel = LOGL_NOTICE,
	},
	[DCTRL] = {
		.name = "DCTRL",
		.description = "Control interface",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DSMPP] = {
		.name = "DSMPP",
		.description = "SMPP interface for external SMS apps",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DRANAP] = {
		.name = "DRANAP",
		.description = "Radio Access Network Application Part Protocol",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DVLR] = {
		.name = "DVLR",
		.description = "Visitor Location Register",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DIUCS] = {
		.name = "DIUCS",
		.description = "Iu-CS Protocol",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DBSSAP] = {
		.name = "DBSSAP",
		.description = "BSSAP Protocol (A Interface)",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DSGS] = {
		.name = "DSGS",
		.description = "SGs Interface (SGsAP)",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DSS] = {
		.name = "DSS",
		.description = "Supplementary Services",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
	[DASCI] = {
		.name = "DASCI",
		.description = "Advanced Speech Call Items",
		.enabled = 1, .loglevel = LOGL_NOTICE,
	},
};

static int filter_fn(const struct log_context *ctx, struct log_target *tar)
{
	const struct vlr_subscr *vsub = ctx->ctx[LOG_CTX_VLR_SUBSCR];

	if ((tar->filter_map & (1 << LOG_FLT_VLR_SUBSCR)) != 0
	    && vsub && vsub == tar->filter_data[LOG_FLT_VLR_SUBSCR])
		return 1;

	return 0;
}

const struct log_info log_info = {
	.filter_fn = filter_fn,
	.cat = msc_default_categories,
	.num_cat = ARRAY_SIZE(msc_default_categories),
};

extern void *tall_gsms_ctx;
extern void *tall_call_ctx;
extern void *tall_trans_ctx;

static int msc_mgw_setup(void)
{
	struct mgcp_client *mgcp_client_single;
	unsigned int pool_members_initalized;

	/* Initialize MGW pool. This initalizes and connects all MGCP clients that are currently configured in
	 * the pool. Adding additional MGCP clients to the pool is possible but the user has to configure and
	 * (re)connect them manually from the VTY. */
	if (!mgcp_client_pool_empty(msc_network->mgw.mgw_pool)) {
		pool_members_initalized = mgcp_client_pool_connect(msc_network->mgw.mgw_pool);
		if (!pool_members_initalized) {
			LOGP(DMSC, LOGL_ERROR, "MGW pool failed to initialize any pool members\n");
			return -EINVAL;
		}
		LOGP(DMSC, LOGL_NOTICE,
		     "MGW pool with %u pool members configured, (ignoring MGW configuration in VTY node 'msc').\n",
		     pool_members_initalized);
		return 0;
	}

	/* Initialize and connect a single MGCP client. This MGCP client will appear as the one and only pool
	 * member if there is no MGW pool configured. */
	LOGP(DMSC, LOGL_NOTICE, "No MGW pool configured, using MGW configuration in VTY node 'msc'\n");
	mgcp_client_single = mgcp_client_init(msc_network, msc_network->mgw.conf);
	if (!mgcp_client_single) {
		LOGP(DMSC, LOGL_ERROR, "MGW (single) client initalization failed\n");
		return -EINVAL;
	}
	if (mgcp_client_connect(mgcp_client_single)) {
		LOGP(DMSC, LOGL_ERROR, "MGW (single) connect failed at (%s:%u)\n",
		     msc_network->mgw.conf->remote_addr,
		     msc_network->mgw.conf->remote_port);
		return -EINVAL;
	}
	mgcp_client_pool_register_single(msc_network->mgw.mgw_pool, mgcp_client_single);

	return 0;
}

int main(int argc, char **argv)
{
	int rc;
	int ret = 0;

	struct osmo_sccp_instance *sccp_a;
	struct osmo_sccp_instance *sccp_iu;
	const struct osmo_ss7_instance *ss7;

	/* Track the use of talloc NULL memory contexts */
	talloc_enable_null_tracking();

	osmo_fsm_set_dealloc_ctx(OTC_SELECT);

	msc_vty_info.copyright	= osmomsc_copyright;

	tall_msc_ctx = talloc_named_const(NULL, 1, "osmo_msc");
	msc_vty_info.tall_ctx = tall_msc_ctx;

	msgb_talloc_ctx_init(tall_msc_ctx, 0);
	osmo_signal_talloc_ctx_init(tall_msc_ctx);
	tall_gsms_ctx = talloc_named_const(tall_msc_ctx, 0, "sms");
	tall_call_ctx = talloc_named_const(tall_msc_ctx, 0, "gsm_call");
	tall_trans_ctx = talloc_named_const(tall_msc_ctx, 0, "transaction");

	osmo_init_logging2(tall_msc_ctx, &log_info);

	osmo_fsm_log_timeouts(true);
	osmo_fsm_log_addr(true);

	osmo_stats_init(tall_msc_ctx);
	rate_ctr_init(tall_msc_ctx);

	/* For --version, vty_init() must be called before handling options */
	vty_init(&msc_vty_info);

	OSMO_ASSERT(osmo_ss7_init() == 0);
	osmo_ss7_vty_init_asp(tall_msc_ctx);
	osmo_sccp_vty_init();
	ctrl_vty_init(tall_msc_ctx);
	logging_vty_add_cmds();
	osmo_talloc_vty_add_cmds();
	osmo_cpu_sched_vty_init(tall_msc_ctx);

	/* Allocate global gsm_network struct.
	 * At first set the internal MNCC as default, may be changed below according to cfg or cmdline option. */
	msc_network = msc_network_alloc(tall_msc_ctx, int_mncc_recv);
	if (!msc_network)
		return -ENOMEM;

	msc_vty_init(msc_network);

	/* Parse options */
	handle_options(argc, argv);

	call_leg_init(msc_network);
	mncc_call_fsm_init(msc_network);

	if (msc_vlr_alloc(msc_network)) {
		fprintf(stderr, "Failed to allocate VLR\n");
		exit(1);
	}

#ifdef BUILD_SMPP
	if (smpp_msc_alloc_init(tall_msc_ctx) < 0)
		return -1;
#endif
	sgs_iface_init(tall_msc_ctx, msc_network);

	rc = vty_read_config_file(msc_cmdline_config.config_file, NULL);
	if (rc < 0) {
		LOGP(DMSC, LOGL_FATAL, "Failed to parse the config file: '%s'\n",
		     msc_cmdline_config.config_file);
		return 1;
	}

	/* Initialize MNCC socket if appropriate. If the cmdline option -M is present, it overrides the .cfg file
	 * setting 'msc' / 'mncc external MNCC_SOCKET_PATH'. Note that when -M is given, it "bleeds" back into the vty
	 * 'write' command and is reflected in the written out 'mncc external' cfg. */
	if (msc_cmdline_config.mncc_sock_path) {
		LOGP(DMNCC, LOGL_NOTICE,
		     "MNCC socket path is configured from commandline argument -M."
		     " This affects a written-back config file. Instead consider using the config file directly"
		     " ('msc' / 'mncc external MNCC_SOCKET_PATH').\n");
		gsm_network_set_mncc_sock_path(msc_network, msc_cmdline_config.mncc_sock_path);
	}
	if (msc_network->mncc_sock_path) {
		msc_network->mncc_recv = mncc_sock_from_cc;
		rc = mncc_sock_init(msc_network,
				    msc_network->mncc_sock_path);
		if (rc) {
			fprintf(stderr, "MNCC socket initialization failed. exiting.\n");
			exit(1);
		}
	} else
		DEBUGP(DMNCC, "Using internal MNCC handler.\n");

	/* start telnet after reading config for vty_get_bind_addr() */
	rc = telnet_init_default(tall_msc_ctx, &msc_network, OSMO_VTY_PORT_MSC);
	if (rc < 0)
		return 2;

	/* BSC stuff is to be split behind an A-interface to be used with
	 * OsmoBSC, but there is no need to remove it yet. Most of the
	 * following code until iu_init() is legacy. */

#ifdef BUILD_SMPP
	smpp_msc_start(msc_network);
#endif

	/* start control interface after reading config for
	 * ctrl_vty_get_bind_addr() */
	msc_network->ctrl = ctrl_interface_setup(msc_network, OSMO_CTRL_PORT_MSC, NULL);
	if (!msc_network->ctrl) {
		fprintf(stderr, "Failed to initialize control interface. Exiting.\n");
		return -1;
	}

#if 0
TODO: we probably want some of the _net_ ctrl commands from bsc_base_ctrl_cmds_install().
	if (bsc_base_ctrl_cmds_install() != 0) {
		fprintf(stderr, "Failed to initialize the BSC control commands.\n");
		return -1;
	}
#endif

	if (msc_ctrl_cmds_install(msc_network) != 0) {
		fprintf(stderr, "Failed to initialize the MSC control commands.\n");
		return -1;
	}

	/* seed the PRNG */
	srand(time(NULL));
	/* TODO: is this used for crypto?? Improve randomness, at least we
	 * should try to use the nanoseconds part of the current time. */

	if (msc_gsup_client_start(msc_network)) {
		fprintf(stderr, "Failed to start GSUP client\n");
		exit(1);
	}

	msc_a_i_t_gsup_init(msc_network);

	if (msc_vlr_start(msc_network)) {
		fprintf(stderr, "Failed to start VLR\n");
		exit(1);
	}

	signal(SIGINT, &signal_handler);
	signal(SIGTERM, &signal_handler);
	signal(SIGABRT, &signal_handler);
	signal(SIGUSR1, &signal_handler);
	signal(SIGUSR2, &signal_handler);
	osmo_init_ignore_signals();

	/* start the SMS queue */
	if (sms_queue_start(msc_network) != 0) {
		ret = -1;
		goto error;
	}

	if (msc_mgw_setup() != 0) {
		ret = 7;
		goto error;
	}

	if (ss7_setup(tall_msc_ctx, &sccp_a, &sccp_iu)) {
		fprintf(stderr, "Setting up SCCP client failed.\n");
		ret = 8;
		goto error;
	}

	if (sgs_server_open(g_sgs)) {
		fprintf(stderr, "Starting SGs server failed\n");
		ret = 9;
		goto error;
	}

	msc_network->a.sri = sccp_ran_init(msc_network, sccp_a, OSMO_SCCP_SSN_BSSAP,
					   "OsmoMSC-A", &msc_ran_infra[OSMO_RAT_GERAN_A],
					   msc_network);
	if (!msc_network->a.sri) {
		fprintf(stderr, "Setting up A receiver failed\n");
		ret = 10;
		goto error;
	}

	ss7 = osmo_sccp_get_ss7(msc_network->a.sri->sccp);
	OSMO_ASSERT(ss7);
	LOGP(DMSC, LOGL_NOTICE, "A-interface: SCCP user %s, cs7-instance %u (%s)\n",
	     osmo_sccp_user_name(msc_network->a.sri->scu),
	     osmo_ss7_instance_get_id(ss7),
	     osmo_ss7_instance_get_name(ss7));

#ifdef BUILD_IU
	talloc_asn1_ctx = talloc_named_const(tall_msc_ctx, 0, "asn1");

	msc_network->iu.sri = sccp_ran_init(msc_network, sccp_iu, OSMO_SCCP_SSN_RANAP,
					   "OsmoMSC-IuCS", &msc_ran_infra[OSMO_RAT_UTRAN_IU],
					   msc_network);
	if (!msc_network->iu.sri) {
		fprintf(stderr, "Setting up IuCS receiver failed\n");
		ret = 11;
		goto error;
	}

	/* Compatibility with legacy osmo-hnbgw that was unable to properly handle RESET messages. */
	msc_network->iu.sri->ignore_missing_reset = true;

	ss7 = osmo_sccp_get_ss7(msc_network->iu.sri->sccp);
	LOGP(DMSC, LOGL_NOTICE, "Iu-interface: SCCP user %s, cs7-instance %u (%s)\n",
	     osmo_sccp_user_name(msc_network->iu.sri->scu),
	     osmo_ss7_instance_get_id(ss7),
	     osmo_ss7_instance_get_name(ss7));
#endif

	/* Init RRLP handlers */
	msc_rrlp_init();

	if (msc_cmdline_config.daemonize) {
		rc = osmo_daemonize();
		if (rc < 0) {
			perror("Error during daemonize");
			ret = 6;
			goto error;
		}
	}

	do {
		log_reset_context();
		osmo_select_main_ctx(0);

		/* If the user hits Ctrl-C the third time, just terminate immediately. */
		if (quit >= 3)
			break;

		/* Has SIGTERM been received (and not yet been handled)? */
		if (quit && !osmo_select_shutdown_requested()) {
			msc_network_shutdown(msc_network);
			osmo_signal_dispatch(SS_L_GLOBAL, S_L_GLOBAL_SHUTDOWN, NULL);

			/* Request write-only mode in osmo_select_main_ctx() */
			osmo_select_shutdown_request();
			/* continue the main select loop until all write queues are serviced. */
		}
	} while (!osmo_select_shutdown_done());

error:
	db_fini();
	log_fini();

	/**
	 * Report the heap state of root context, then free,
	 * so both ASAN and Valgrind are happy...
	 */
	talloc_report_full(tall_msc_ctx, stderr);
	talloc_free(tall_msc_ctx);

	/* FIXME: VTY code still uses NULL-context */
	talloc_free(tall_vty_ctx);

	/**
	 * Report the heap state of NULL context, then free,
	 * so both ASAN and Valgrind are happy...
	 */
	talloc_report_full(NULL, stderr);
	talloc_disable_null_tracking();
	return ret;
}
