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module MGCP_Test {
	import from Osmocom_Types all;
	import from MGCP_Types all;
	import from MGCP_Templates all;
	import from SDP_Types all;
	import from MGCP_CodecPort all;
	import from MGCP_CodecPort_CtrlFunct all;
	import from RTP_CodecPort all;
	import from RTP_CodecPort_CtrlFunct all;
	import from RTP_Emulation all;
	import from IPL4asp_Types all;

	const charstring c_mgw_domain := "mgw";
	const charstring c_mgw_ep_rtpbridge := "rtpbridge/";

	/* any variables declared in the component will be available to
	 * all functions that 'run on' the named component, similar to
	 * class members in C++ */
	type component dummy_CT {
		port MGCP_CODEC_PT MGCP;
		var boolean initialized := false;
		var ConnectionId g_mgcp_conn_id := -1;
		var integer g_trans_id;

		var RTP_Emulation_CT vc_RTPEM[3];
		port RTPEM_CTRL_PT RTPEM[3];
	};

	function get_next_trans_id() runs on dummy_CT return MgcpTransId {
		var MgcpTransId tid := int2str(g_trans_id);
		g_trans_id := g_trans_id + 1;
		return tid;
	}

	/* all parameters declared here can be modified / overridden by
	 * the config file in the [MODULE_PARAMETERS] section. If no
	 * config file is used or the file doesn't specify them, the
	 * default values assigned below are used */
	modulepar {
		PortNumber mp_local_udp_port := 2727;
		charstring mp_local_ip := "127.0.0.1";
		PortNumber mp_remote_udp_port := 2427;
		charstring mp_remote_ip := "127.0.0.1";
		PortNumber mp_local_rtp_port_base := 10000;
	}

	private function f_rtpem_init(inout RTP_Emulation_CT comp_ref, integer i)
	runs on dummy_CT {
		comp_ref := RTP_Emulation_CT.create("RTPEM" & int2str(i));
		map(comp_ref:RTP, system:RTP);
		map(comp_ref:RTCP, system:RTCP);
		comp_ref.start(RTP_Emulation.f_main());
	}

	/* initialization function, called by each test case at the
	 * beginning, but 'initialized' variable ensures its body is
	 * only executed once */
	private function f_init(template MgcpEndpoint ep := omit) runs on dummy_CT {
		var Result res;
		var uint32_t ssrc;

		if (initialized == false) {
			initialized := true;

			/* some random number for the initial transaction id */
			g_trans_id := float2int(rnd()*65535.0);
			map(self:MGCP, system:MGCP_CODEC_PT);
			/* connect the MGCP test port using the given
			 * source/destionation ip/port and store the connection id in g_mgcp_conn_id
			 * */
			res := MGCP_CodecPort_CtrlFunct.f_IPL4_connect(MGCP, mp_remote_ip, mp_remote_udp_port, mp_local_ip, mp_local_udp_port, 0, { udp := {} });
			if (not ispresent(res.connId)) {
				setverdict(fail, "Could not connect MGCP, check your configuration");
				self.stop;
			}
			g_mgcp_conn_id := res.connId;

			for (var integer i := 0; i < sizeof(vc_RTPEM); i := i+1) {
				f_rtpem_init(vc_RTPEM[i], i);
				connect(vc_RTPEM[i]:CTRL, self:RTPEM[i]);
			}
		}

		if (isvalue(ep)) {
			/* do a DLCX on all connections of the EP */
			f_dlcx_ignore(valueof(ep));
		}
	}

	testcase TC_selftest() runs on dummy_CT {
		const charstring c_auep := "AUEP 158663169 ds/e1-1/2@172.16.6.66 MGCP 1.0\r\n";
		const charstring c_mdcx3 := "MDCX 18983215 " & c_mgw_ep_rtpbridge & "1@" & c_mgw_domain & " MGCP 1.0\r\n";
		const charstring c_mdcx3_ret := "200 18983215 OK\r\n" &
						"I: 1\n" &
						"\n" &
						"v=0\r\n" &
						"o=- 1 23 IN IP4 0.0.0.0\r\n" &
						"s=-\r\n" &
						"c=IN IP4 0.0.0.0\r\n" &
						"t=0 0\r\n" &
						"m=audio 0 RTP/AVP 126\r\n" &
						"a=rtpmap:126 AMR/8000\r\n" &
						"a=ptime:20\r\n";
		const charstring c_mdcx4 :=	"MDCX 18983216 " & c_mgw_ep_rtpbridge & "1@" & c_mgw_domain & " MGCP 1.0\r\n" &
						"M: sendrecv\r" &
						"C: 2\r\n" &
						"I: 1\r\n" &
						"L: p:20, a:AMR, nt:IN\r\n" &
						"\n" &
						"v=0\r\n" &
						"o=- 1 23 IN IP4 0.0.0.0\r\n" &
						"s=-\r\n" &
						"c=IN IP4 0.0.0.0\r\n" &
						"t=0 0\r\n" &
						"m=audio 4441 RTP/AVP 99\r\n" &
						"a=rtpmap:99 AMR/8000\r\n" &
						"a=ptime:40\r\n";
		const charstring c_crcx510_ret := "510 23 FAIL\r\n"

		log(c_auep);
		log(dec_MgcpCommand(c_auep));

		log(c_mdcx3);
		log(dec_MgcpCommand(c_mdcx3));

		log(c_mdcx3_ret);
		log(dec_MgcpResponse(c_mdcx3_ret));

		log(c_mdcx4);
		log(dec_MgcpCommand(c_mdcx4));

		log(ts_CRCX("23", c_mgw_ep_rtpbridge & "42@" & c_mgw_domain, "sendrecv", '1234'H));
		log(enc_MgcpCommand(valueof(ts_CRCX("23", c_mgw_ep_rtpbridge & "42@" & c_mgw_domain, "sendrecv", '1234'H))));

		log(c_crcx510_ret);
		log(dec_MgcpResponse(c_crcx510_ret));
		log(dec_MgcpMessage(c_crcx510_ret));
	}

	/* CRCX test ideas:
	 * x without mandatory CallId
	 * - with forbidden parameters (e.g. Capabilities, PackageList, ...
	 * - CRCX with remote session description and without
	 *
	 * general ideas:
	 * x packetization != 20ms
	 * x invalid mode
	 * x unsupported mode (517)
	 * x bidirectional mode before RemoteConnDesc: 527
	 * - invalid codec
	 * x retransmission of same transaction
	 * - unsupported LocalConnectionOptions ("b", "a", "e", "gc", "s", "r", "k", ..)
	 */

	/* build a receive template for receiving a MGCP message. You
	 * pass the MGCP response template in, and it will generate an
	 * MGCP_RecvFrom template that can match the primitives arriving on the
	 * MGCP_CodecPort */
	function tr_MGCP_RecvFrom_R(template MgcpResponse resp) runs on dummy_CT return template MGCP_RecvFrom {
		var template MGCP_RecvFrom mrf := {
			connId := g_mgcp_conn_id,
			remName := mp_remote_ip,
			remPort := mp_remote_udp_port,
			locName := mp_local_ip,
			locPort := mp_local_udp_port,
			msg := { response := resp }
		}
		return mrf;
	}

	/* Send a MGCP request + receive a (matching!) response */
	function mgcp_transceive_mgw(template MgcpCommand cmd, template MgcpResponse resp := ?) runs on dummy_CT return MgcpResponse {
		var MgcpMessage msg := { command := valueof(cmd) };
		resp.line.trans_id := cmd.line.trans_id;
		var template MGCP_RecvFrom mrt := tr_MGCP_RecvFrom_R(resp);
		var MGCP_RecvFrom mrf;
		timer T := 5.0;

		MGCP.send(t_MGCP_Send(g_mgcp_conn_id, msg));
		T.start;
		alt {
			[] MGCP.receive(mrt) -> value mrf { }
			[] MGCP.receive(tr_MGCP_RecvFrom_R(?)) { setverdict(fail); }
			[] MGCP.receive { repeat; }
			[] T.timeout { setverdict(fail); }
		}
		T.stop;

		if (isbound(mrf) and isbound(mrf.msg) and ischosen(mrf.msg.response)) {
			return mrf.msg.response;
		} else {
			var MgcpResponse r := { line := { code := "999", trans_id := valueof(cmd.line.trans_id) } };
			return r;
		}
	}

	function extract_conn_id(MgcpResponse resp) return MgcpConnectionId {
		var integer i;
		for (i := 0; i < lengthof(resp.params); i := i + 1) {
			var MgcpParameter par := resp.params[i];
			if (par.code == "I") {
				return str2hex(par.val);
			}
		}
		setverdict(fail);
		return '00000000'H;
	}

	function f_dlcx(MgcpEndpoint ep, template MgcpResponseCode ret_code, template charstring ret_val,
			template MgcpCallId call_id := omit,
			template MgcpConnectionId conn_id := omit) runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var template MgcpResponse rtmpl := {
			line := {
				code := ret_code,
				string := ret_val
			},
			params := *,
			sdp := *
		};
		cmd := ts_DLCX(get_next_trans_id(), ep, call_id, conn_id);
		resp := mgcp_transceive_mgw(cmd, rtmpl);
	}

	/* Send DLCX and expect OK response */
	function f_dlcx_ok(MgcpEndpoint ep, template MgcpCallId call_id := omit,
			   template MgcpConnectionId conn_id := omit) runs on dummy_CT {
		f_dlcx(ep, ("200","250"), "OK", call_id, conn_id);
	}

	/* Send DLCX and accept any response */
	function f_dlcx_ignore(MgcpEndpoint ep, template MgcpCallId call_id := omit,
				template MgcpConnectionId conn_id := omit) runs on dummy_CT {
		f_dlcx(ep, ?, *, call_id, conn_id);
	}

	type record HostPort {
		charstring hostname,
		integer portnr optional
	}
	type record RtpFlowData {
		HostPort em,	/* emulation side */
		HostPort mgw,	/* mgw side */
		uint7_t pt,
		charstring codec,
		MgcpConnectionId mgcp_conn_id optional,
		RtpemConfig rtp_cfg optional
	}

	/* Create an RTP flow (bidirectional, or receive-only) */
	function f_flow_create(RTPEM_CTRL_PT pt, MgcpEndpoint ep, MgcpCallId call_id, charstring mode, inout RtpFlowData flow,
				boolean one_phase := true)
	runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;

		/* bind local RTP emulation socket */
		f_rtpem_bind(pt, flow.em.hostname, flow.em.portnr);

		/* configure rtp-emulation */
		if (ispresent(flow.rtp_cfg)) {
			f_rtpem_configure(pt, flow.rtp_cfg);
		} else {
			var RtpemConfig rtp_cfg := c_RtpemDefaultCfg;
			rtp_cfg.tx_payload_type := flow.pt
			f_rtpem_configure(pt, rtp_cfg);
		}

		if (one_phase) {
			/* Connect flow to MGW using a CRCX that also contains an SDP
			 * part that tells the MGW where we are listening for RTP streams
			 * that come from the MGW. We get a fully working connection in
			 * one go. */

			cmd := ts_CRCX(get_next_trans_id(), ep, mode, call_id);
			cmd.sdp := ts_SDP(flow.em.hostname, flow.em.hostname, "23", "42",
					  flow.em.portnr, { int2str(flow.pt) },
					  { valueof(ts_SDP_rtpmap(flow.pt, flow.codec)),
					    valueof(ts_SDP_ptime(20)) });
			resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);
			flow.mgcp_conn_id := extract_conn_id(resp);
			/* extract port number from response */
			flow.mgw.portnr :=
				resp.sdp.media_list[0].media_field.ports.port_number;
		} else {
			/* Create a half-open connection only. We do not tell the MGW
			 * where it can send RTP streams to us. This means this
			 * connection will only be able to receive but can not send
			 * data back to us. In order to turn the connection in a fully
			 * bi-directional one, a separate MDCX is needed. */

			cmd := ts_CRCX(get_next_trans_id(), ep, mode, call_id);
			resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);
			flow.mgcp_conn_id := extract_conn_id(resp);
			/* extract MGW-side port number from response */
			flow.mgw.portnr :=
				resp.sdp.media_list[0].media_field.ports.port_number;
		}
		/* finally, connect the emulation-side RTP socket to the MGW */
		f_rtpem_connect(pt, flow.mgw.hostname, flow.mgw.portnr);
	}

	/* Modify an existing RTP flow */
	function f_flow_modify(RTPEM_CTRL_PT pt, MgcpEndpoint ep, MgcpCallId call_id, charstring mode, inout RtpFlowData flow)
	runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;

		/* rebind local RTP emulation socket to the new address */
		f_rtpem_bind(pt, flow.em.hostname, flow.em.portnr);

		/* reconfigure rtp-emulation */
		if (ispresent(flow.rtp_cfg)) {
			f_rtpem_configure(pt, flow.rtp_cfg);
		} else {
			var RtpemConfig rtp_cfg := c_RtpemDefaultCfg;
			rtp_cfg.tx_payload_type := flow.pt
			f_rtpem_configure(pt, rtp_cfg);
		}

		/* connect MGW side RTP socket to the emulation-side RTP socket using SDP */
		cmd := ts_MDCX(get_next_trans_id(), ep, mode, call_id, flow.mgcp_conn_id);
		cmd.sdp := ts_SDP(flow.em.hostname, flow.em.hostname, "23", "42",
				  flow.em.portnr, { int2str(flow.pt) },
				  { valueof(ts_SDP_rtpmap(flow.pt, flow.codec)),
				    valueof(ts_SDP_ptime(20)) });
		resp := mgcp_transceive_mgw(cmd, tr_MDCX_ACK);

		/* extract MGW-side port number from response. (usually this
		 * will not change, but thats is up to the MGW) */
		flow.mgw.portnr :=
			resp.sdp.media_list[0].media_field.ports.port_number;

		/* reconnect the emulation-side RTP socket to the MGW */
		f_rtpem_connect(pt, flow.mgw.hostname, flow.mgw.portnr);
	}

	/* Delete an existing RTP flow */
	function f_flow_delete(RTPEM_CTRL_PT pt, template MgcpEndpoint ep := omit, template MgcpCallId call_id := omit)
	runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;

		/* Switch off RTP flow */
		f_rtpem_mode(pt, RTPEM_MODE_NONE);

		/* Delete connection on MGW (if needed) */
		if (isvalue(call_id) and isvalue(ep)) {
			f_sleep(0.1);
			f_dlcx_ok(valueof(ep), call_id);
		}
	}

	function f_crcx(charstring ep_prefix) runs on dummy_CT {
		var MgcpEndpoint ep := ep_prefix & "2@" & c_mgw_domain;
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpCallId call_id := '1234'H;

		f_init(ep);

		/* create the connection on the MGW */
		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);
		extract_conn_id(resp);

		/* clean-up */
		f_dlcx_ok(ep, call_id);
	}

	function f_crcx_no_lco(charstring ep_prefix) runs on dummy_CT {
		var MgcpEndpoint ep := ep_prefix & "2@" & c_mgw_domain;
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpCallId call_id := '1234'H;

		f_init(ep);

		/* create the connection on the MGW */
		cmd := ts_CRCX_no_lco(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);
		extract_conn_id(resp);

		/* clean-up */
		f_dlcx_ok(ep, call_id);

		/* See also OS#2658: Even when we omit the LCO information, we
		   expect the MGW to pick a sane payload type for us. This
		   payload type should be visible in the SDP of the response. */
		if (resp.sdp.media_list[0].media_field.fmts[0] != "0") {
			setverdict(fail, "SDP contains unexpected codec");
		}

		/* See also OS#2658: We also expect the MGW to assign a port
		   number to us. */
		if (isbound(resp.sdp.media_list[0].media_field.ports.port_number) == false) {
			setverdict(fail, "SDP does not contain a port number");
		}
	}

	/* test valid CRCX without SDP */
	testcase TC_crcx() runs on dummy_CT {
		f_crcx(c_mgw_ep_rtpbridge);
		setverdict(pass);
	}

	/* test valid CRCX without SDP and LCO */
	testcase TC_crcx_no_lco() runs on dummy_CT {
		f_crcx_no_lco(c_mgw_ep_rtpbridge);
		setverdict(pass);
	}

	/* test valid CRCX without SDP (older method without endpoint prefix) */
	testcase TC_crcx_noprefix() runs on dummy_CT {
		f_crcx("");
		setverdict(pass);
	}

	/* test CRCX with unsupported mode, expect 517 */
	testcase TC_crcx_unsupp_mode() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1233'H;
		var template MgcpResponse rtmpl := tr_MgcpResp_Err("517");

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "netwtest", call_id);
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* test CRCX with early bi-directional mode, expect 527 as
	 * bi-diretional media can only  be established once both local and
	 * remote side are specified, see MGCP RFC */
	testcase TC_crcx_early_bidir_mode() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1232'H;
		var template MgcpResponse rtmpl := tr_MgcpResp_Err("527");

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "sendrecv", call_id);
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* test CRCX with unsupported Parameters */
	testcase TC_crcx_unsupp_param() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1231'H;
		var template MgcpResponse rtmpl := tr_MgcpResp_Err("539");

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		/* osmo-bsc_mgcp/mgw doesn't implement notifications */
		f_mgcp_par_append(cmd.params, MgcpParameter:{ "N", "foobar" });

		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* test CRCX with missing CallId */
	testcase TC_crcx_missing_callid() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var template MgcpResponse rtmpl := tr_MgcpResp_Err(("400","516"));

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", '1230'H);
		cmd.params := {
			t_MgcpParConnMode("recvonly"),
			t_MgcpParLocConnOpt("p:20")
		}
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);

	}

	/* test CRCX with missing Mode */
	testcase TC_crcx_missing_mode() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1229'H;
		var template MgcpResponse rtmpl := tr_MgcpResp_Err(("400","517"));

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		cmd.params := {
			ts_MgcpParCallId(call_id),
			t_MgcpParLocConnOpt("p:20")
		}
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* test CRCX with unsupported packetization interval */
	testcase TC_crcx_unsupp_packet_intv() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1228'H;
		var template MgcpResponse rtmpl := tr_MgcpResp_Err("535");

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		cmd.params[2] := t_MgcpParLocConnOpt("p:111");
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* test CRCX with illegal double presence of local connection option */
	testcase TC_crcx_illegal_double_lco() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1227'H;
		var template MgcpResponse rtmpl := tr_MgcpResp_Err("524");

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		/* p:20 is permitted only once and not twice! */
		cmd.params[2] := t_MgcpParLocConnOpt("p:20, a:AMR, p:20");
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* test valid CRCX with valid SDP */
	testcase TC_crcx_sdp() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1226'H;

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "sendrecv", call_id);
		cmd.sdp := ts_SDP("127.0.0.1", "127.0.0.2", "23", "42", 2344, { "98" },
				  { valueof(ts_SDP_rtpmap(98, "AMR/8000")),
				    valueof(ts_SDP_ptime(20)) });
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);

		/* clean-up */
		f_dlcx_ok(ep, call_id);

		setverdict(pass);
	}

	/* test valid wildcarded CRCX */
	testcase TC_crcx_wildcarded() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "*@" & c_mgw_domain;
		var MgcpCallId call_id := '1234'H;
		var MgcpEndpoint ep_assigned;
		f_init();

		/* create the connection on the MGW */
		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);
		extract_conn_id(resp);

		/* extract endpoint name we got assigned by the MGW */
		var MgcpMessage resp_msg := {
			response := resp
		}
		if (f_mgcp_find_param(resp_msg, "Z", ep_assigned) == false) {
			setverdict(fail, "No SpecificEndpointName in MGCP response", resp);
		}

		/* clean-up */
		f_dlcx_ok(ep_assigned, call_id);

		setverdict(pass);
	}

	/* test valid wildcarded CRCX */
	testcase TC_crcx_wildcarded_exhaust() runs on dummy_CT {
		const integer n_endpoints := 32;
		var integer i;
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "*@" & c_mgw_domain;
		var MgcpCallId call_id := '1234'H;
		var MgcpEndpoint ep_assigned[n_endpoints];
		f_init();

		/* Exhaust all endpoint resources on the virtual trunk */
		for (i := 0; i < n_endpoints; i := i+1) {
			cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
			resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);

			/* Make sure we got a connection id */
			extract_conn_id(resp);

			var MgcpMessage resp_msg := {
			    response := resp
			}
			if (f_mgcp_find_param(resp_msg, "Z", ep_assigned[i]) == false) {
				setverdict(fail, "No SpecificEndpointName in MGCP response", resp);
			}
		}

		/* Try to allocate one more endpoint, which should fail */
		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		var template MgcpResponse rtmpl := tr_MgcpResp_Err("403");
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);

		/* clean-up */
		for (i := 0; i < n_endpoints; i := i+1) {
		    f_dlcx_ok(ep_assigned[i], call_id);
		}
		setverdict(pass);
	}

	/* TODO: various SDP related bits */


	/* TODO: CRCX with X-Osmux */
	/* TODO: double CRCX without force_realloc */

	/* TODO: MDCX (various) */

	/* TODO: MDCX without CRCX first */
	testcase TC_mdcx_without_crcx() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "3@" & c_mgw_domain;
		var MgcpCallId call_id := '1225'H;
		var template MgcpResponse rtmpl := {
			line := {
				/* TODO: accept/enforce better error? */
				code := "400",
				string := ?
			},
			params:= { },
			sdp := omit
		};

		f_init(ep);

		cmd := ts_MDCX(get_next_trans_id(), ep, "sendrecv", call_id, call_id);
		cmd.sdp := ts_SDP("127.0.0.1", "127.0.0.2", "23", "42", 2344, { "98" },
				  { valueof(ts_SDP_rtpmap(98, "AMR/8000")),
				    valueof(ts_SDP_ptime(20)) });
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* DLCX without CRCX first */
	testcase TC_dlcx_without_crcx() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "4@" & c_mgw_domain;
		var template MgcpResponse rtmpl := {
			line := {
				code := ("400", "515"),
				string := ?
			},
			params:= { },
			sdp := omit
		};

		f_init(ep);

		cmd := ts_DLCX(get_next_trans_id(), ep, '41234'H);
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* test valid wildcarded MDCX */
	testcase TC_mdcx_wildcarded() runs on dummy_CT {
		 /* Note: A wildcarded MDCX is not allowed, so we expect the
		  * MGW to reject this request */
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "*@" & c_mgw_domain;
		var MgcpCallId call_id := '1225'H;
		var template MgcpResponse rtmpl := {
			line := {
				/* TODO: accept/enforce better error? */
				code := "507",
				string := ?
			},
			params:= { },
			sdp := omit
		};

		f_init(ep);

		cmd := ts_MDCX(get_next_trans_id(), ep, "sendrecv", call_id, call_id);
		cmd.sdp := ts_SDP("127.0.0.1", "127.0.0.2", "23", "42", 2344, { "98" },
				  { valueof(ts_SDP_rtpmap(98, "AMR/8000")),
				    valueof(ts_SDP_ptime(20)) });
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* test valid wildcarded DLCX */
	testcase TC_dlcx_wildcarded() runs on dummy_CT {
		 /* Note: A wildcarded DLCX is specified, but our MGW does not
		  * support this feature so we expect the MGW to reject the
		  * request */
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "*@" & c_mgw_domain;
		var template MgcpResponse rtmpl := {
			line := {
				code := "507",
				string := ?
			},
			params:= { },
			sdp := omit
		};

		f_init(ep);

		cmd := ts_DLCX(get_next_trans_id(), ep, '41234'H);
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		setverdict(pass);
	}

	/* Test (valid) CRCX followed by (valid) DLCX containig EP+CallId+ConnId */
	testcase TC_crcx_and_dlcx_ep_callid_connid() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "5@" & c_mgw_domain;
		var MgcpCallId call_id := '51234'H;

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);

		f_dlcx_ok(ep, call_id, extract_conn_id(resp));

		setverdict(pass);
	}

	function f_crcx_and_dlcx_ep_callid_connid(MgcpEndpoint ep, MgcpCallId call_id) runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);

		f_dlcx_ok(ep, call_id, extract_conn_id(resp));

		setverdict(pass);
	}

	testcase TC_crcx_dlcx_30ep() runs on dummy_CT {
		var MgcpEndpoint ep;
		var MgcpCallId call_id;
		var integer ep_nr;

		f_init();

		for (ep_nr := 1; ep_nr < 30; ep_nr := ep_nr+1) {
			ep := c_mgw_ep_rtpbridge & hex2str(int2hex(ep_nr, 2)) & "@" & c_mgw_domain;
			call_id := int2hex(ep_nr, 2) & '1234'H;
			f_crcx_and_dlcx_ep_callid_connid(ep, call_id);
		}
	}

	/* Test (valid) CRCX followed by (valid) DLCX containing EP+CallId */
	testcase TC_crcx_and_dlcx_ep_callid() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "5@" & c_mgw_domain;
		var MgcpCallId call_id := '51233'H;

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);

		f_dlcx_ok(ep, call_id);

		setverdict(pass);
	}

	/* Test (valid) CRCX followed by (valid) DLCX containing EP */
	testcase TC_crcx_and_dlcx_ep() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "5@" & c_mgw_domain;
		var MgcpCallId call_id := '51232'H;

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);

		f_dlcx_ok(ep);

		setverdict(pass);
	}


	/* CRCX + DLCX of valid endpoint but invalid call-id */
	testcase TC_crcx_and_dlcx_ep_callid_inval() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "5@" & c_mgw_domain;
		var MgcpCallId call_id := '51231'H;

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);

		f_dlcx(ep, "516", *, 'ffff'H);

		setverdict(pass);
	}


	/* CRCX + DLCX of valid endpoint and call-id but invalid conn-id */
	testcase TC_crcx_and_dlcx_ep_callid_connid_inval() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "5@" & c_mgw_domain;
		var MgcpCallId call_id := '51230'H;

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);

		f_dlcx(ep, "515", *, call_id, 'ffff'H);

		setverdict(pass);
	}


	/* TODO: Double-DLCX (retransmission) */
	testcase TC_crcx_and_dlcx_retrans() runs on dummy_CT {
		var template MgcpCommand cmd;
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "5@" & c_mgw_domain;
		var MgcpCallId call_id := '51229'H;
		var template MgcpResponse rtmpl := {
			line := {
				code := "200",
				string := "OK"
			},
			params:= { },
			sdp := omit
		};

		f_init(ep);

		cmd := ts_CRCX(get_next_trans_id(), ep, "recvonly", call_id);
		resp := mgcp_transceive_mgw(cmd, tr_CRCX_ACK);

		cmd := ts_DLCX(get_next_trans_id(), ep, call_id);
		resp := mgcp_transceive_mgw(cmd, rtmpl);
		resp := mgcp_transceive_mgw(cmd, rtmpl);

		setverdict(pass);
	}

	template (value) RtpFlowData t_RtpFlow(charstring host_a, charstring host_b, uint7_t pt,
						charstring codec) := {
		em := {
			hostname := host_a,
			portnr := omit
		},
		mgw := {
			hostname := host_b,
			portnr := omit
		},
		pt := pt,
		codec := codec
	}

	/* transmit RTP streams between two RTP Emulations back-to-back; expect no loss */
	testcase TC_rtpem_selftest() runs on dummy_CT {
		var RtpemStats stats[2];
		var integer local_port := 10000;
		var integer local_port2 := 20000;

		f_init();

		f_rtpem_bind(RTPEM[0], "127.0.0.1", local_port);
		f_rtpem_bind(RTPEM[1], "127.0.0.2", local_port2);

		f_rtpem_connect(RTPEM[0], "127.0.0.2", local_port2);
		f_rtpem_connect(RTPEM[1], "127.0.0.1", local_port);

		log("=== starting");
		f_rtpem_mode(RTPEM[0], RTPEM_MODE_BIDIR);
		f_rtpem_mode(RTPEM[1], RTPEM_MODE_BIDIR);

		f_sleep(5.0);

		log("=== stopping");
		f_rtpem_mode(RTPEM[1], RTPEM_MODE_RXONLY);
		f_rtpem_mode(RTPEM[0], RTPEM_MODE_RXONLY);
		f_sleep(0.5);
		f_rtpem_mode(RTPEM[1], RTPEM_MODE_NONE);
		f_rtpem_mode(RTPEM[0], RTPEM_MODE_NONE);

		stats[0] := f_rtpem_stats_get(RTPEM[0]);
		stats[1] := f_rtpem_stats_get(RTPEM[1]);
		if (not f_rtpem_stats_compare(stats[0], stats[1])) {
			setverdict(fail, "RTP endpoint statistics don't match");
		}
		setverdict(pass);
	}

	/* Create one half open connection in receive-only mode. The MGW must accept
	 * the packets but must not send any. */
	testcase TC_one_crcx_receive_only_rtp() runs on dummy_CT {
		var RtpFlowData flow;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "1@" & c_mgw_domain;
		var MgcpCallId call_id := '1225'H;
		var RtpemStats stats;

		f_init(ep);
		flow := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 112, "AMR/8000/1"));
		flow.em.portnr := 10000;
		f_flow_create(RTPEM[0], ep, call_id, "recvonly", flow, false);

		f_rtpem_mode(RTPEM[0], RTPEM_MODE_TXONLY);
		f_sleep(1.0);
		f_flow_delete(RTPEM[0], ep, call_id);

		stats := f_rtpem_stats_get(RTPEM[0]);

		if (stats.num_pkts_tx < 40) {
			setverdict(fail);
		}
		if (stats.bytes_payload_tx < 190) {
			setverdict(fail);
		}
		if (stats.num_pkts_rx != 0) {
			setverdict(fail);
		}
		if (stats.num_pkts_rx_err_seq != 0) {
			setverdict(fail);
		}
		if (stats.num_pkts_rx_err_ts != 0) {
			setverdict(fail);
		}
		if (stats.num_pkts_rx_err_disabled != 0) {
			setverdict(fail);
		}

		setverdict(pass);
	}

	/* Create one connection in loopback mode, test if the RTP packets are
	 * actually reflected */
	testcase TC_one_crcx_loopback_rtp() runs on dummy_CT {
		var RtpFlowData flow;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "1@" & c_mgw_domain;
		var MgcpCallId call_id := '1225'H;
		var RtpemStats stats;

		f_init(ep);
		flow := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 111, "GSM-HR-08/8000/1"));
		flow.em.portnr := 10000;
		f_flow_create(RTPEM[0], ep, call_id, "loopback", flow);

		f_rtpem_mode(RTPEM[0], RTPEM_MODE_BIDIR);
		f_sleep(1.0);
		f_flow_delete(RTPEM[0], ep, call_id);

		stats := f_rtpem_stats_get(RTPEM[0]);

		if (stats.num_pkts_tx != stats.num_pkts_rx) {
			setverdict(fail);
		}
		if (stats.bytes_payload_tx != stats.bytes_payload_rx) {
			setverdict(fail);
		}
		if (stats.num_pkts_rx_err_seq != 0) {
			setverdict(fail);
		}
		if (stats.num_pkts_rx_err_ts != 0) {
			setverdict(fail);
		}
		if (stats.num_pkts_rx_err_disabled != 0) {
			setverdict(fail);
		}

		setverdict(pass);
	}

	function f_TC_two_crcx_and_rtp(boolean bidir) runs on dummy_CT {
		var RtpFlowData flow[2];
		var RtpemStats stats[2];
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1226'H;
		var integer tolerance := 0;

		f_init(ep);

		/* from us to MGW */
		flow[0] := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 98, "AMR/8000"));
		/* bind local RTP emulation sockets */
		flow[0].em.portnr := 10000;
		f_flow_create(RTPEM[0], ep, call_id, "sendrecv", flow[0]);

		/* from MGW back to us */
		flow[1] := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 98, "AMR/8000"));
		flow[1].em.portnr := 20000;
		f_flow_create(RTPEM[1], ep, call_id, "sendrecv", flow[1]);

		if (bidir) {
				f_rtpem_mode(RTPEM[0], RTPEM_MODE_BIDIR);
				f_rtpem_mode(RTPEM[1], RTPEM_MODE_BIDIR);

				/* Note: When we test bidirectional we may
				 * loose packets during switch off because
				 * both ends are transmitting and we only
				 * can switch them off one by one. */
				tolerance := 3;
		} else {
				f_rtpem_mode(RTPEM[0], RTPEM_MODE_RXONLY);
				f_rtpem_mode(RTPEM[1], RTPEM_MODE_TXONLY);
		}

		f_sleep(1.0);

		f_flow_delete(RTPEM[1]);
		f_flow_delete(RTPEM[0], ep, call_id);

		stats[0] := f_rtpem_stats_get(RTPEM[0]);
		stats[1] := f_rtpem_stats_get(RTPEM[1]);
		if (not f_rtpem_stats_compare(stats[0], stats[1], tolerance)) {
			setverdict(fail, "RTP endpoint statistics don't match");
		}

		setverdict(pass);
	}

	/* create two local RTP emulations; create two connections on MGW EP, exchange some data */
	testcase TC_two_crcx_and_rtp() runs on dummy_CT {
		 f_TC_two_crcx_and_rtp(false);
	}

	/* create two local RTP emulations; create two connections on MGW EP,
	 * exchange some data in both directions */
	testcase TC_two_crcx_and_rtp_bidir() runs on dummy_CT {
		 f_TC_two_crcx_and_rtp(true);
	}

	/* create two local RTP emulations and pass data in both directions */
	testcase TC_two_crcx_mdcx_and_rtp() runs on dummy_CT {
		var RtpFlowData flow[2];
		var RtpemStats stats[2];
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1227'H;
		var integer num_pkts_tx[2];
		var integer temp;

		f_init(ep);

		/* Create the first connection in receive only mode */
		flow[0] := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 3, "GSM/8000/1"));
		flow[0].em.portnr := 10000;
		f_flow_create(RTPEM[0], ep, call_id, "recvonly", flow[0], false);

		/* Create the second connection. This connection will be also
		 * in receive only mode */
		flow[1] := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 3, "GSM/8000/1"));
		flow[1].em.portnr := 20000;
		f_flow_create(RTPEM[1], ep, call_id, "recvonly", flow[1], false);

		/* The first leg starts transmitting */
		f_rtpem_mode(RTPEM[0], RTPEM_MODE_TXONLY);
		f_sleep(0.5);
		stats[0] := f_rtpem_stats_get(RTPEM[0]);
		if (stats[0].num_pkts_rx_err_disabled != 0) {
			setverdict(fail, "received packets from MGW on recvonly connection");
		}
		stats[1] := f_rtpem_stats_get(RTPEM[1]);
		if (stats[1].num_pkts_rx_err_disabled != 0) {
			setverdict(fail, "received packets from MGW on recvonly connection");
		}

		/* The second leg starts transmitting a little later */
		f_rtpem_mode(RTPEM[1], RTPEM_MODE_TXONLY);
		f_sleep(1.0);
		stats[0] := f_rtpem_stats_get(RTPEM[0]);
		if (stats[0].num_pkts_rx_err_disabled != 0) {
			setverdict(fail, "received packets from MGW on recvonly connection");
		}
		stats[1] := f_rtpem_stats_get(RTPEM[1]);
		if (stats[1].num_pkts_rx_err_disabled != 0) {
			setverdict(fail, "received packets from MGW on recvonly connection");
		}

		/* The first leg will now be switched into bidirectional
		 * mode, but we do not expect any data comming back yet. */
		f_flow_modify(RTPEM[0], ep, call_id, "sendrecv", flow[0]);
		f_sleep(0.5);
		stats[0] := f_rtpem_stats_get(RTPEM[0]);
		if (stats[1].num_pkts_rx_err_disabled != 0) {
			setverdict(fail, "received packets from MGW on recvonly connection");
		}
		stats[1] := f_rtpem_stats_get(RTPEM[1]);
		if (stats[1].num_pkts_rx_err_disabled != 0) {
			setverdict(fail, "received packets from MGW on recvonly connection");
		}

		/* When the second leg is switched into bidirectional mode
		 * as well, then the MGW will connect the two together and
		 * we should see RTP streams passing through from both ends. */
		f_rtpem_mode(RTPEM[0], RTPEM_MODE_BIDIR);
		f_rtpem_mode(RTPEM[1], RTPEM_MODE_BIDIR);
		stats[0] := f_rtpem_stats_get(RTPEM[0]);
		num_pkts_tx[0] := stats[0].num_pkts_tx
		stats[1] := f_rtpem_stats_get(RTPEM[1]);
		num_pkts_tx[1] := stats[1].num_pkts_tx

		f_flow_modify(RTPEM[1], ep, call_id, "sendrecv", flow[1]);
		f_sleep(2.0);

		stats[0] := f_rtpem_stats_get(RTPEM[0]);
		stats[1] := f_rtpem_stats_get(RTPEM[1]);

		temp := stats[0].num_pkts_tx - num_pkts_tx[0] - stats[1].num_pkts_rx;
		if (temp > 3 or temp < -3) {
			setverdict(fail, "number of packets not within normal parameters");
		}

		temp := stats[1].num_pkts_tx - num_pkts_tx[1] - stats[0].num_pkts_rx;
		if (temp > 3 or temp < -3) {
			setverdict(fail, "number of packets not within normal parameters");
		}

		/* Tear down */
		f_flow_delete(RTPEM[0]);
		f_flow_delete(RTPEM[1], ep, call_id);
		setverdict(pass);
	}

	/* Test what happens when two RTP streams from different sources target
	 * a single connection. Is the unsolicited stream properly ignored? */
	testcase TC_two_crcx_and_unsolicited_rtp() runs on dummy_CT {
		var RtpFlowData flow[2];
		var RtpemStats stats[2];
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "2@" & c_mgw_domain;
		var MgcpCallId call_id := '1234321326'H;
		var integer unsolicited_port := 10002;

		f_init(ep);

		/* from us to MGW */
		flow[0] := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 98, "AMR/8000"));
		/* bind local RTP emulation sockets */
		flow[0].em.portnr := 10000;
		f_flow_create(RTPEM[0], ep, call_id, "sendrecv", flow[0]);

		/* from MGW back to us */
		flow[1] := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 98, "AMR/8000"));
		flow[1].em.portnr := 20000;
		f_flow_create(RTPEM[1], ep, call_id, "sendrecv", flow[1]);

		f_rtpem_mode(RTPEM[1], RTPEM_MODE_RXONLY);
		f_rtpem_mode(RTPEM[0], RTPEM_MODE_TXONLY);

		f_sleep(0.5);

		/* Start inserting unsolicited RTP packets */
		f_rtpem_bind(RTPEM[2], mp_local_ip, unsolicited_port);
		f_rtpem_connect(RTPEM[2], mp_remote_ip, flow[0].mgw.portnr);
		f_rtpem_mode(RTPEM[2], RTPEM_MODE_TXONLY);

		f_sleep(0.5);

		f_flow_delete(RTPEM[0]);
		f_flow_delete(RTPEM[1], ep, call_id);

		stats[0] := f_rtpem_stats_get(RTPEM[0]);
		stats[1] := f_rtpem_stats_get(RTPEM[1]);
		if (not f_rtpem_stats_compare(stats[0], stats[1])) {
			setverdict(fail, "RTP endpoint statistics don't match");
		}

		setverdict(pass);
	}

	/* Test a handover situation. We first create two connections transmit
	 * some data bidirectionally. Then we will simulate a handover situation. */
	testcase TC_two_crcx_and_one_mdcx_rtp_ho() runs on dummy_CT {
		var RtpFlowData flow[2];
		var RtpemStats stats[3];
		var MgcpResponse resp;
		var MgcpEndpoint ep := c_mgw_ep_rtpbridge & "4@" & c_mgw_domain;
		var MgcpCallId call_id := '76338'H;
		var integer port_old;

		f_init(ep);

		/* First connection (BTS) */
		flow[0] := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 110, "GSM-EFR/8000"));
		/* bind local RTP emulation sockets */
		flow[0].em.portnr := 10000;
		f_flow_create(RTPEM[0], ep, call_id, "sendrecv", flow[0]);

		/* Second connection (PBX) */
		flow[1] := valueof(t_RtpFlow(mp_local_ip, mp_remote_ip, 110, "GSM-EFR/8000"));
		flow[1].em.portnr := 20000;
		f_flow_create(RTPEM[1], ep, call_id, "sendrecv", flow[1]);

		/* Normal rtp flow for one second */
		f_rtpem_mode(RTPEM[0], RTPEM_MODE_BIDIR);
		f_rtpem_mode(RTPEM[1], RTPEM_MODE_BIDIR);
		f_sleep(1.0);

		/* Now switch the flow over to a new port (BTS) */
		port_old := flow[0].em.portnr;
		flow[0].em.portnr := 10002;
		f_flow_modify(RTPEM[0], ep, call_id, "sendrecv", flow[0]);

		/* When handing over a call, the old source may still keep
		 * transmitting for a while. We simulate this by injecting
		 * some unsolicited packets on the behalf of the old source,
		 * (old remote port) */
		f_rtpem_bind(RTPEM[2], mp_local_ip, port_old);
		f_rtpem_connect(RTPEM[2], mp_remote_ip, flow[0].mgw.portnr);
		f_rtpem_mode(RTPEM[2], RTPEM_MODE_TXONLY);
		f_sleep(1.0);
		f_rtpem_mode(RTPEM[2], RTPEM_MODE_NONE);
		f_sleep(1.0);

		/* Terminate call */
		f_flow_delete(RTPEM[0]);
		f_flow_delete(RTPEM[1], ep, call_id);

		stats[0] := f_rtpem_stats_get(RTPEM[0]);
		stats[1] := f_rtpem_stats_get(RTPEM[1]);
		if (not f_rtpem_stats_compare(stats[0], stats[1], 5)) {
			setverdict(fail, "RTP endpoint statistics don't match");
		}
		stats[2] := f_rtpem_stats_get(RTPEM[2]);
		if (stats[2].num_pkts_rx_err_disabled != 0) {
			setverdict(fail, "received packets on old leg after handover");
		}

		setverdict(pass);
	}

	/* TODO: Double-DLCX (no retransmission) */



	/* TODO: AUEP (various) */
	/* TODO: RSIP (various) */
	/* TODO: RQNT (various) */
	/* TODO: EPCF (various) */
	/* TODO: AUCX (various) */
	/* TODO: invalid verb (various) */

	control {
		execute(TC_selftest());
		execute(TC_crcx());
		execute(TC_crcx_no_lco());
		execute(TC_crcx_noprefix());
		execute(TC_crcx_unsupp_mode());
		execute(TC_crcx_early_bidir_mode());
		execute(TC_crcx_unsupp_param());
		execute(TC_crcx_missing_callid());
		execute(TC_crcx_missing_mode());
		execute(TC_crcx_unsupp_packet_intv());
		execute(TC_crcx_illegal_double_lco());
		execute(TC_crcx_sdp());
		execute(TC_crcx_wildcarded());
		execute(TC_crcx_wildcarded_exhaust());
		execute(TC_mdcx_without_crcx());
		execute(TC_dlcx_without_crcx());
		execute(TC_mdcx_wildcarded());
		execute(TC_dlcx_wildcarded());
		execute(TC_crcx_and_dlcx_ep_callid_connid());
		execute(TC_crcx_and_dlcx_ep_callid());
		execute(TC_crcx_and_dlcx_ep());
		execute(TC_crcx_and_dlcx_ep_callid_inval());
		execute(TC_crcx_and_dlcx_ep_callid_connid_inval());
		execute(TC_crcx_and_dlcx_retrans());

		execute(TC_crcx_dlcx_30ep());

		execute(TC_rtpem_selftest());

		execute(TC_one_crcx_receive_only_rtp());
		execute(TC_one_crcx_loopback_rtp());
		execute(TC_two_crcx_and_rtp());
		execute(TC_two_crcx_and_rtp_bidir());
		execute(TC_two_crcx_mdcx_and_rtp());
		execute(TC_two_crcx_and_unsolicited_rtp());
		execute(TC_two_crcx_and_one_mdcx_rtp_ho());
	}
}