Rename BSSMAP_Emulation -> RAN_Emulation
So far, BSSMAP_Emulation supported only a transport over BSSMAP.
However, we soon intend to merge support for RANAP in order to
simulate RANAP/Iu connections as well as BSSMAP. Let's start
by renaming some of the existing types/functions/ports/modules
without introducing any functional changes just yet.
Related: OS#2857, OS#2856
Change-Id: Iecbcb0c6c136baad9460eca40606bb4010d8882d
diff --git a/library/RAN_Emulation.ttcn b/library/RAN_Emulation.ttcn
new file mode 100644
index 0000000..72e2733
--- /dev/null
+++ b/library/RAN_Emulation.ttcn
@@ -0,0 +1,836 @@
+module RAN_Emulation {
+
+/* RAN Emulation, runs on top of BSSAP_CodecPort. It multiplexes/demultiplexes
+ * the individual connections, so there can be separate TTCN-3 components handling
+ * each of the connections.
+ *
+ * The RAN_Emulation.main() function processes SCCP primitives from the SCCP
+ * stack via the BSSAP_CodecPort, and dispatches them to the per-connection components.
+ *
+ * Outbound BSSAP/SCCP connections are initiated by sending a BSSAP_Conn_Req primitive
+ * to the component running the RAN_Emulation.main() function.
+ *
+ * For each new inbound connections, the RanOps.create_cb() is called. It can create
+ * or resolve a TTCN-3 component, and returns a component reference to which that inbound
+ * connection is routed/dispatched.
+ *
+ * If a pre-existing component wants to register to handle a future inbound connection, it can
+ * do so by registering an "expect" with the expected Layer 3 (DTAP) payload. This is e.g. useful
+ * if you are simulating BTS + MSC, and first trigger a connection from BTS/RSL side in a
+ * component which then subsequently should also handle the MSC emulation.
+ *
+ * Inbound Unit Data messages (such as are dispatched to the RanOps.unitdata_cb() callback,
+ * which is registered with an argument to the main() function below.
+ *
+ * (C) 2017-2018 by Harald Welte <laforge@gnumonks.org>
+ * All rights reserved.
+ *
+ * Released under the terms of GNU General Public License, Version 2 or
+ * (at your option) any later version.
+ */
+
+
+import from General_Types all;
+import from Osmocom_Types all;
+import from SCCP_Emulation all;
+import from SCCPasp_Types all;
+import from BSSAP_Types all;
+import from BSSAP_CodecPort all;
+import from BSSMAP_Templates all;
+import from MGCP_Types all;
+import from MGCP_Templates all;
+import from IPA_Emulation all;
+import from MobileL3_Types all;
+
+/* General "base class" component definition, of which specific implementations
+ * derive themselves by means of the "extends" feature */
+type component RAN_ConnHdlr {
+ /* port towards MSC Emulator core / SCCP connection dispatchar */
+ port RAN_Conn_PT BSSAP;
+ /* procedure based port to register for incoming connections */
+ port RAN_PROC_PT BSSAP_PROC;
+}
+
+/* Auxiliary primitive that can happen on the port between per-connection client and this dispatcher */
+type enumerated RAN_Conn_Prim {
+ /* SCCP tell us that connection was released */
+ MSC_CONN_PRIM_DISC_IND,
+ /* we tell SCCP to release connection */
+ MSC_CONN_PRIM_DISC_REQ,
+ /* Connection confirmed indication */
+ MSC_CONN_PRIM_CONF_IND
+}
+
+type record BSSAP_Conn_Req {
+ SCCP_PAR_Address addr_peer,
+ SCCP_PAR_Address addr_own,
+ PDU_BSSAP bssap
+}
+
+/* similar to PDU_BSSAP with DTAP, but DTAP is already decoded! */
+type record PDU_DTAP_MO {
+ OCT1 dlci optional,
+ boolean skip_seq_patching optional,
+ PDU_ML3_MS_NW dtap
+}
+
+/* similar to PDU_BSSAP with DTAP, but DTAP is already decoded! */
+type record PDU_DTAP_MT {
+ OCT1 dlci optional,
+ PDU_ML3_NW_MS dtap
+}
+
+template PDU_DTAP_MT ts_PDU_DTAP_MT(template PDU_ML3_NW_MS dtap, template OCT1 dlci := omit) := {
+ dlci := dlci,
+ dtap := dtap
+}
+
+template PDU_DTAP_MO ts_PDU_DTAP_MO(template PDU_ML3_MS_NW dtap, template OCT1 dlci := '00'O, boolean skip_seq_patching := false) := {
+ dlci := dlci,
+ skip_seq_patching := skip_seq_patching,
+ dtap := dtap
+}
+
+template PDU_DTAP_MT tr_PDU_DTAP_MT(template PDU_ML3_NW_MS dtap, template OCT1 dlci := *) := {
+ dlci := dlci,
+ dtap := dtap
+}
+
+template PDU_DTAP_MO tr_PDU_DTAP_MO(template PDU_ML3_MS_NW dtap, template OCT1 dlci := *) := {
+ dlci := dlci,
+ skip_seq_patching := ?,
+ dtap := dtap
+}
+
+template BSSAP_Conn_Req ts_BSSAP_Conn_Req(SCCP_PAR_Address peer, SCCP_PAR_Address own, PDU_BSSAP bssap) := {
+ addr_peer := peer,
+ addr_own := own,
+ bssap := bssap
+};
+
+
+/* port between individual per-connection components and this dispatcher */
+type port RAN_Conn_PT message {
+ /* BSSAP or direct DTAP messages from/to clients */
+ inout PDU_BSSAP, PDU_DTAP_MO, PDU_DTAP_MT,
+ /* misc indications / requests between SCCP and client */
+ RAN_Conn_Prim,
+ /* Client requests us to create SCCP Connection */
+ BSSAP_Conn_Req,
+ /* MGCP, only used for IPA SCCPlite (MGCP in IPA mux) */
+ MgcpCommand, MgcpResponse;
+} with { extension "internal" };
+
+
+/* represents a single BSSAP connection over SCCP */
+type record ConnectionData {
+ /* reference to the instance of the per-connection component */
+ RAN_ConnHdlr comp_ref,
+ integer sccp_conn_id,
+ /* most recent MGCP transaction ID (Used on MSC side) */
+ MgcpTransId mgcp_trans_id optional,
+ /* CIC that has been used for voice of this channel (BSC side) */
+ integer cic optional,
+ /* array of N(SD) values for MO DTAP messages, indexed by discriminator */
+ uint2_t n_sd[4]
+}
+
+type record ImsiMapping {
+ RAN_ConnHdlr comp_ref,
+ hexstring imsi optional,
+ OCT4 tmsi
+}
+
+type component RAN_Emulation_CT {
+ /* SCCP port on the bottom side, using ASP primitives */
+ port BSSAP_CODEC_PT BSSAP;
+ /* BSSAP port to the per-connection clients */
+ port RAN_Conn_PT CLIENT;
+ /* MGCP port */
+ port IPA_MGCP_PT MGCP;
+
+ /* use 16 as this is also the number of SCCP connections that SCCP_Emulation can handle */
+ var ConnectionData ConnectionTable[16];
+
+ /* pending expected incoming connections */
+ var ExpectData ExpectTable[8];
+
+ /* tables for mapping inbound unitdata (like paging) */
+ var ImsiMapping ImsiTable[16];
+
+ /* procedure based port to register for incoming connections */
+ port RAN_PROC_PT PROC;
+
+ var charstring g_ran_id;
+ var integer g_next_e1_ts := 1;
+ var RanOps g_ran_ops;
+};
+
+private function f_conn_id_known(integer sccp_conn_id)
+runs on RAN_Emulation_CT return boolean {
+ var integer i;
+ for (i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].sccp_conn_id == sccp_conn_id){
+ return true;
+ }
+ }
+ return false;
+}
+
+private function f_comp_known(RAN_ConnHdlr client)
+runs on RAN_Emulation_CT return boolean {
+ var integer i;
+ for (i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].comp_ref == client) {
+ return true;
+ }
+ }
+ return false;
+}
+
+private function f_cic_known(integer cic)
+runs on RAN_Emulation_CT return boolean {
+ var integer i;
+ for (i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].cic == cic) {
+ return true;
+ }
+ }
+ return false;
+}
+
+/* resolve component reference by connection ID */
+private function f_comp_by_conn_id(integer sccp_conn_id)
+runs on RAN_Emulation_CT return RAN_ConnHdlr {
+ var integer i;
+ for (i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].sccp_conn_id == sccp_conn_id) {
+ return ConnectionTable[i].comp_ref;
+ }
+ }
+ setverdict(fail, "RAN Connection table not found by SCCP Connection ID ", sccp_conn_id);
+ mtc.stop;
+}
+
+/* resolve component reference by CIC */
+private function f_comp_by_mgcp_tid(MgcpTransId tid)
+runs on RAN_Emulation_CT return RAN_ConnHdlr {
+ var integer i;
+ for (i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].mgcp_trans_id == tid) {
+ return ConnectionTable[i].comp_ref;
+ }
+ }
+ setverdict(fail, "RAN Connection table not found by MGCP Transaction ID ", tid);
+ mtc.stop;
+}
+
+private function f_comp_store_mgcp_tid(RAN_ConnHdlr client, MgcpTransId tid)
+runs on RAN_Emulation_CT {
+ var integer i;
+ for (i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].comp_ref == client) {
+ ConnectionTable[i].mgcp_trans_id := tid;
+ return;
+ }
+ }
+ setverdict(fail, "RAN Connection table not found by component ", client);
+ mtc.stop;
+}
+
+private function f_comp_by_cic(integer cic)
+runs on RAN_Emulation_CT return RAN_ConnHdlr {
+ var integer i;
+ for (i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].cic == cic) {
+ return ConnectionTable[i].comp_ref;
+ }
+ }
+ setverdict(fail, "RAN Connection table not found by CIC ", cic);
+ mtc.stop;
+}
+
+private function f_comp_store_cic(RAN_ConnHdlr client, integer cic)
+runs on RAN_Emulation_CT {
+ var integer i;
+ for (i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].comp_ref == client) {
+ ConnectionTable[i].cic := cic;
+ return;
+ }
+ }
+ setverdict(fail, "RAN Connection table not found by component ", client);
+ mtc.stop;
+}
+
+/* resolve connection ID by component reference */
+private function f_conn_id_by_comp(RAN_ConnHdlr client)
+runs on RAN_Emulation_CT return integer {
+ for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].comp_ref == client) {
+ return ConnectionTable[i].sccp_conn_id;
+ }
+ }
+ setverdict(fail, "RAN Connection table not found by component ", client);
+ mtc.stop;
+}
+
+/* resolve ConnectionTable index component reference */
+private function f_idx_by_comp(RAN_ConnHdlr client)
+runs on RAN_Emulation_CT return integer {
+ for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].comp_ref == client) {
+ return i;
+ }
+ }
+ setverdict(fail, "RAN Connection table not found by component ", client);
+ mtc.stop;
+}
+
+private function f_gen_conn_id()
+runs on RAN_Emulation_CT return integer {
+ var integer conn_id;
+
+ do {
+ conn_id := float2int(rnd()*SCCP_Emulation.tsp_max_ConnectionId);
+ } while (f_conn_id_known(conn_id) == true);
+
+ return conn_id;
+}
+
+private function f_conn_table_init()
+runs on RAN_Emulation_CT {
+ for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ ConnectionTable[i].comp_ref := null;
+ ConnectionTable[i].sccp_conn_id := -1;
+ ConnectionTable[i].mgcp_trans_id := omit;
+ ConnectionTable[i].cic := omit;
+ ConnectionTable[i].n_sd := { 0, 0, 0, 0 };
+ }
+ for (var integer i := 0; i < sizeof(ImsiTable); i := i+1) {
+ ImsiTable[i].comp_ref := null;
+ ImsiTable[i].imsi := omit;
+ ImsiTable[i].tmsi := 'FFFFFFFF'O;
+ }
+}
+
+private function f_conn_table_add(RAN_ConnHdlr comp_ref, integer sccp_conn_id)
+runs on RAN_Emulation_CT {
+ for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].sccp_conn_id == -1) {
+ ConnectionTable[i].comp_ref := comp_ref;
+ ConnectionTable[i].sccp_conn_id := sccp_conn_id;
+ ConnectionTable[i].n_sd := { 0, 0, 0, 0 };
+ log("Added conn table entry ", i, comp_ref, sccp_conn_id);
+ return;
+ }
+ }
+ testcase.stop("RAN Connection table full!");
+}
+
+private function f_conn_table_del(integer sccp_conn_id)
+runs on RAN_Emulation_CT {
+ for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) {
+ if (ConnectionTable[i].sccp_conn_id == sccp_conn_id) {
+ log("Deleted conn table entry ", i,
+ ConnectionTable[i].comp_ref, sccp_conn_id);
+ ConnectionTable[i].sccp_conn_id := -1;
+ ConnectionTable[i].comp_ref := null;
+ return
+ }
+ }
+ setverdict(fail, "RAN Connection table attempt to delete non-existant ", sccp_conn_id);
+ mtc.stop;
+}
+
+private function f_imsi_table_find(hexstring imsi, template OCT4 tmsi)
+runs on RAN_Emulation_CT return RAN_ConnHdlr {
+ for (var integer i := 0; i < sizeof(ImsiTable); i := i+1) {
+ if (ImsiTable[i].imsi == imsi or
+ isvalue(tmsi) and match(ImsiTable[i].tmsi, tmsi)) {
+ return ImsiTable[i].comp_ref;
+ }
+ }
+ return null;
+}
+
+/* handle (optional) userData portion of various primitives and dispatch it to the client */
+private function f_handle_userData(RAN_ConnHdlr client, PDU_BSSAP bssap)
+runs on RAN_Emulation_CT {
+ /* decode + send decoded BSSAP to client */
+
+ if (ischosen(bssap.pdu.bssmap)) {
+ /* BSC Side: If this is an assignment command, store CIC */
+ if (ischosen(bssap.pdu.bssmap.assignmentRequest) and
+ ispresent(bssap.pdu.bssmap.assignmentRequest.circuitIdentityCode)) {
+ var BSSMAP_IE_CircuitIdentityCode cic_ie :=
+ bssap.pdu.bssmap.assignmentRequest.circuitIdentityCode;
+ var integer cic := (oct2int(cic_ie.cicHigh) * 256) + oct2int(cic_ie.cicLow);
+ f_comp_store_cic(client, cic);
+ }
+ }
+
+ if (ischosen(bssap.pdu.dtap) and g_ran_ops.decode_dtap) {
+ if (g_ran_ops.role_ms) {
+ /* we are the MS, so any message to us must be MT */
+ var PDU_DTAP_MT mt := {
+ dlci := bssap.dlci,
+ dtap := dec_PDU_ML3_NW_MS(bssap.pdu.dtap)
+ };
+ CLIENT.send(mt) to client;
+ } else {
+ /* we are the Network, so any message to us must be MO */
+ var PDU_DTAP_MO mo := {
+ dlci := bssap.dlci,
+ dtap := dec_PDU_ML3_MS_NW(bssap.pdu.dtap)
+ };
+ CLIENT.send(mo) to client;
+ }
+ } else {
+ CLIENT.send(bssap) to client;
+ }
+}
+
+/* call-back type, to be provided by specific implementation; called when new SCCP connection
+ * arrives */
+type function BssmapCreateCallback(BSSAP_N_CONNECT_ind conn_ind, charstring id)
+runs on RAN_Emulation_CT return RAN_ConnHdlr;
+
+type function BssmapUnitdataCallback(PDU_BSSAP bssap)
+runs on RAN_Emulation_CT return template PDU_BSSAP;
+
+/* handle common Unitdata such as Paging */
+private function CommonBssmapUnitdataCallback(PDU_BSSAP bssap)
+runs on RAN_Emulation_CT return template PDU_BSSAP {
+ if (match(bssap, tr_BSSMAP_Paging)) {
+ var RAN_ConnHdlr client := null;
+ client := f_imsi_table_find(bssap.pdu.bssmap.paging.iMSI.digits,
+ bssap.pdu.bssmap.paging.tMSI.tmsiOctets);
+ if (client != null) {
+ log("CommonBssmapUnitdataCallback: IMSI/TMSI found in table, dispatching to ",
+ client);
+ CLIENT.send(bssap) to client;
+ return omit;
+ }
+ log("CommonBssmapUnitdataCallback: IMSI/TMSI not found in table");
+ } else {
+ log("CommonBssmapUnitdataCallback: Not a paging message");
+ }
+ /* ELSE: handle in user callback */
+ return g_ran_ops.unitdata_cb.apply(bssap);
+}
+
+type record RanOps {
+ BssmapCreateCallback create_cb,
+ BssmapUnitdataCallback unitdata_cb,
+ boolean decode_dtap,
+ boolean role_ms,
+ /* needed for performing BSSMAP RESET */
+ SCCP_PAR_Address sccp_addr_local optional,
+ SCCP_PAR_Address sccp_addr_peer optional
+}
+
+template BIT4 t_ML3_DISC_CC_MM_SS := ('0011'B, '0101'B, '1011'B);
+
+/* patch N(SD) into enc_l3, according to 24.007 11.2.3.2 */
+function f_ML3_patch_seq(inout ConnectionData cd, in PDU_ML3_MS_NW dtap, inout octetstring enc_l3) {
+ var uint2_t seq_nr;
+ if (ischosen(dtap.msgs.cc) or ischosen(dtap.msgs.mm) or ischosen(dtap.msgs.ss)) {
+ seq_nr := cd.n_sd[0];
+ cd.n_sd[0] := (cd.n_sd[0] + 1) mod 4;
+ } else if (ischosen(dtap.msgs.gcc)) {
+ seq_nr := cd.n_sd[1];
+ cd.n_sd[1] := (cd.n_sd[1] + 1) mod 2;
+ } else if (ischosen(dtap.msgs.bcc)) {
+ seq_nr := cd.n_sd[2];
+ cd.n_sd[2] := (cd.n_sd[2] + 1) mod 2;
+ } else if (ischosen(dtap.msgs.loc)) {
+ seq_nr := cd.n_sd[3];
+ cd.n_sd[3] := (cd.n_sd[3] + 1) mod 2;
+ } else {
+ /* no sequence number to patch */
+ return;
+ }
+ log("patching N(SD)=", seq_nr, " into dtap ", enc_l3);
+ enc_l3[1] := (enc_l3[1] and4b '3f'O) or4b bit2oct(int2bit(seq_nr, 8) << 6);
+ log("patched enc_l3: ", enc_l3);
+}
+
+private function f_bssap_l3_is_rr(PDU_BSSAP bssap) return boolean {
+ var template octetstring l3 := f_bssap_extract_l3(bssap);
+ if (not isvalue(l3)) {
+ return false;
+ }
+ var octetstring l3v := valueof(l3);
+ if (lengthof(l3v) < 1) {
+ return false;
+ }
+ /* lower 4 bits of first octet are protocol discriminator */
+ if ((oct2bit(l3v[0]) and4b '00001111'B) == '00000110'B) {
+ return true;
+ }
+ return false;
+}
+
+private altstep as_reset_ack() runs on RAN_Emulation_CT {
+ var BSSAP_N_UNITDATA_ind ud_ind;
+ [] BSSAP.receive(tr_BSSAP_UNITDATA_ind(?, ?, tr_BSSMAP_Reset)) -> value ud_ind {
+ log("Respoding to inbound RESET with RESET-ACK");
+ BSSAP.send(ts_BSSAP_UNITDATA_req(ud_ind.callingAddress, ud_ind.calledAddress,
+ ts_BSSMAP_ResetAck));
+ repeat;
+ }
+}
+
+
+private function f_bssap_wait_for_reset() runs on RAN_Emulation_CT {
+ var BSSAP_N_UNITDATA_ind ud_ind;
+ timer T := 20.0;
+
+ T.start;
+ alt {
+ [] BSSAP.receive(tr_BSSAP_UNITDATA_ind(?, ?, tr_BSSMAP_Reset)) -> value ud_ind {
+ BSSAP.send(ts_BSSAP_UNITDATA_req(ud_ind.callingAddress, ud_ind.calledAddress,
+ ts_BSSMAP_ResetAck));
+ }
+ [] as_reset_ack();
+ [] BSSAP.receive {
+ repeat;
+ }
+ [] T.timeout {
+ setverdict(fail, "Timeout waiting for BSSAP RESET");
+ mtc.stop;
+ }
+ }
+}
+
+function f_bssap_reset(SCCP_PAR_Address peer, SCCP_PAR_Address own) runs on RAN_Emulation_CT {
+ timer T := 5.0;
+
+ BSSAP.send(ts_BSSAP_UNITDATA_req(peer, own, ts_BSSMAP_Reset(0)));
+ T.start;
+ alt {
+ [] BSSAP.receive(tr_BSSAP_UNITDATA_ind(own, peer, tr_BSSMAP_ResetAck)) {
+ log("Received RESET-ACK in response to RESET, we're ready to go!");
+ }
+ [] as_reset_ack();
+ [] BSSAP.receive { repeat };
+ [] T.timeout {
+ setverdict(fail, "Timeout waiting for RESET-ACK after sending RESET");
+ mtc.stop;
+ }
+ }
+}
+
+function main(RanOps ops, charstring id) runs on RAN_Emulation_CT {
+
+ g_ran_id := id;
+ g_ran_ops := ops;
+ f_conn_table_init();
+ f_expect_table_init();
+
+ if (isvalue(ops.sccp_addr_peer) and isvalue(ops.sccp_addr_local)) {
+ f_sleep(1.0); /* HACK to wait for M3UA/ASP to be ACTIVE */
+ f_bssap_reset(ops.sccp_addr_peer, ops.sccp_addr_local);
+ }
+
+ while (true) {
+ var BSSAP_N_UNITDATA_ind ud_ind;
+ var BSSAP_N_CONNECT_ind conn_ind;
+ var BSSAP_N_CONNECT_cfm conn_cfm;
+ var BSSAP_N_DATA_ind data_ind;
+ var BSSAP_N_DISCONNECT_ind disc_ind;
+ var BSSAP_Conn_Req creq;
+ var RAN_ConnHdlr vc_conn;
+ var PDU_BSSAP bssap;
+ var PDU_DTAP_MO dtap_mo;
+ var PDU_DTAP_MT dtap_mt;
+ var MgcpCommand mgcp_req;
+ var MgcpResponse mgcp_resp;
+ var RAN_ConnHdlr vc_hdlr;
+ var octetstring l3_info;
+ var hexstring imsi;
+ var OCT4 tmsi;
+
+ alt {
+ /* SCCP -> Client: UNIT-DATA (connectionless SCCP) from a BSC */
+ [] BSSAP.receive(BSSAP_N_UNITDATA_ind:?) -> value ud_ind {
+ /* Connectionless Procedures like RESET */
+ var template PDU_BSSAP resp;
+ resp := CommonBssmapUnitdataCallback(ud_ind.userData);
+ if (isvalue(resp)) {
+ BSSAP.send(ts_BSSAP_UNITDATA_req(ud_ind.callingAddress,
+ ud_ind.calledAddress, resp));
+ }
+ }
+
+ /* SCCP -> Client: new connection from BSC */
+ [] BSSAP.receive(BSSAP_N_CONNECT_ind:?) -> value conn_ind {
+ vc_conn := ops.create_cb.apply(conn_ind, id);
+ /* store mapping between client components and SCCP connectionId */
+ f_conn_table_add(vc_conn, conn_ind.connectionId);
+ /* handle user payload */
+ f_handle_userData(vc_conn, conn_ind.userData);
+ /* confirm connection establishment */
+ BSSAP.send(ts_BSSAP_CONNECT_res(conn_ind.connectionId, omit));
+ }
+
+ /* SCCP -> Client: connection-oriented data in existing connection */
+ [] BSSAP.receive(BSSAP_N_DATA_ind:?) -> value data_ind {
+ vc_conn := f_comp_by_conn_id(data_ind.connectionId);
+ if (ispresent(data_ind.userData)) {
+ f_handle_userData(vc_conn, data_ind.userData);
+ }
+ }
+
+ /* SCCP -> Client: disconnect of an existing connection */
+ [] BSSAP.receive(BSSAP_N_DISCONNECT_ind:?) -> value disc_ind {
+ vc_conn := f_comp_by_conn_id(disc_ind.connectionId);
+ if (ispresent(disc_ind.userData)) {
+ f_handle_userData(vc_conn, disc_ind.userData);
+ }
+ /* notify client about termination */
+ var RAN_Conn_Prim prim := MSC_CONN_PRIM_DISC_IND;
+ CLIENT.send(prim) to vc_conn;
+ f_conn_table_del(disc_ind.connectionId);
+ /* TOOD: return confirm to other side? */
+ }
+
+ /* SCCP -> Client: connection confirm for outbound connection */
+ [] BSSAP.receive(BSSAP_N_CONNECT_cfm:?) -> value conn_cfm {
+ vc_conn := f_comp_by_conn_id(conn_cfm.connectionId);
+ var RAN_Conn_Prim prim := MSC_CONN_PRIM_CONF_IND;
+ CLIENT.send(prim) to vc_conn;
+ /* handle user payload */
+ if (ispresent(conn_cfm.userData)) {
+ f_handle_userData(vc_conn, conn_cfm.userData);
+ }
+ }
+
+ /* Disconnect request client -> SCCP */
+ [] CLIENT.receive(RAN_Conn_Prim:MSC_CONN_PRIM_DISC_REQ) -> sender vc_conn {
+ var integer conn_id := f_conn_id_by_comp(vc_conn);
+ BSSAP.send(ts_BSSAP_DISC_req(conn_id, 0));
+ f_conn_table_del(conn_id);
+ }
+
+ /* BSSAP from client -> SCCP */
+ [] CLIENT.receive(BSSAP_Conn_Req:?) -> value creq sender vc_conn {
+ var integer conn_id;
+ /* send to dispatcher */
+
+ if (f_comp_known(vc_conn) == false) {
+ /* unknown client, create new connection */
+ conn_id := f_gen_conn_id();
+
+ /* store mapping between client components and SCCP connectionId */
+ f_conn_table_add(vc_conn, conn_id);
+
+ BSSAP.send(ts_BSSAP_CONNECT_req(creq.addr_peer, creq.addr_own, conn_id,
+ creq.bssap));
+ } else {
+ /* known client, send via existing connection */
+ conn_id := f_conn_id_by_comp(vc_conn);
+ BSSAP.send(ts_BSSAP_DATA_req(conn_id, creq.bssap));
+ }
+
+ /* InitialL3 contains RR (PAG RESP) or MM (CM SRV REQ), we must increment
+ * counter only on MM/CC/SS, but not on RR */
+ if (g_ran_ops.role_ms and not f_bssap_l3_is_rr(creq.bssap)) {
+ /* we have just sent the first MM message, increment the counter */
+ var integer idx := f_idx_by_comp(vc_conn);
+ ConnectionTable[idx].n_sd[0] := 1;
+ log("patch: N(SD) for ConnIdx ", idx, " set to 1");
+ }
+
+ }
+
+ [] CLIENT.receive(PDU_BSSAP:?) -> value bssap sender vc_conn {
+ var integer conn_id := f_conn_id_by_comp(vc_conn);
+ /* send it to dispatcher */
+ BSSAP.send(ts_BSSAP_DATA_req(conn_id, bssap));
+ }
+
+ [g_ran_ops.role_ms] CLIENT.receive(PDU_DTAP_MO:?) -> value dtap_mo sender vc_conn {
+ var integer idx := f_idx_by_comp(vc_conn);
+ /* convert from decoded DTAP to encoded DTAP */
+ var octetstring l3_enc := enc_PDU_ML3_MS_NW(dtap_mo.dtap);
+ /* patch correct L3 send sequence number N(SD) into l3_enc */
+ if (dtap_mo.skip_seq_patching == false) {
+ f_ML3_patch_seq(ConnectionTable[idx], dtap_mo.dtap, l3_enc);
+ }
+ bssap := valueof(ts_BSSAP_DTAP(l3_enc, dtap_mo.dlci));
+ BSSAP.send(ts_BSSAP_DATA_req(ConnectionTable[idx].sccp_conn_id, bssap));
+ }
+
+ [not g_ran_ops.role_ms] CLIENT.receive(PDU_DTAP_MT:?) -> value dtap_mt sender vc_conn {
+ var integer conn_id := f_conn_id_by_comp(vc_conn);
+ /* convert from decoded DTAP to encoded DTAP */
+ var octetstring l3_enc := enc_PDU_ML3_NW_MS(dtap_mt.dtap);
+ bssap := valueof(ts_BSSAP_DTAP(l3_enc, dtap_mo.dlci));
+ BSSAP.send(ts_BSSAP_DATA_req(conn_id, bssap));
+ }
+
+
+ /* Handling of MGCP in IPA SCCPLite case. This predates 3GPP AoIP
+ * and uses a MGCP session in parallel to BSSAP. BSSAP uses CIC
+ * as usual, and MGCP uses "CIC@mgw" endpoint naming, where CIC
+ * is printed as hex string, e.g. a@mgw for CIC 10 */
+
+ /* CLIENT -> MGCP */
+ [] CLIENT.receive(MgcpCommand:?) -> value mgcp_req sender vc_conn {
+ /* MGCP request from Handler (we're MSC) */
+ /* store the transaction ID we've seen */
+ f_comp_store_mgcp_tid(vc_conn, mgcp_req.line.trans_id);
+ /* simply forward any MGCP from the client to the port */
+ MGCP.send(mgcp_req);
+ }
+ [] CLIENT.receive(MgcpResponse:?) -> value mgcp_resp sender vc_conn {
+ /* MGCP response from Handler (we're BSC/MGW) */
+ /* simply forward any MGCP from the client to the port */
+ MGCP.send(mgcp_resp);
+ }
+
+ /* MGCP -> CLIENT */
+ [] MGCP.receive(MgcpCommand:?) -> value mgcp_req {
+ /* MGCP request from network side (we're BSC/MGW) */
+ /* Extract CIC from local part of endpoint name */
+ var integer cic := f_mgcp_ep_extract_cic(mgcp_req.line.ep);
+ if (match(mgcp_req, tr_RSIP) and f_cic_known(cic) == false) {
+ /* ignore RSIP for unknown CIC */
+ } else {
+ /* Resolve the vc_conn by the CIC */
+ vc_conn := f_comp_by_cic(cic);
+ CLIENT.send(mgcp_req) to vc_conn;
+ }
+ }
+ [] MGCP.receive(MgcpResponse:?) -> value mgcp_resp {
+ /* MGCP response from network side (we're MSC) */
+ /* Resolve the vc_conn by the transaction ID */
+ vc_conn := f_comp_by_mgcp_tid(mgcp_resp.line.trans_id);
+ CLIENT.send(mgcp_resp) to vc_conn;
+ }
+
+
+ [] PROC.getcall(RAN_register:{?,?}) -> param(l3_info, vc_hdlr) {
+ f_create_expect(l3_info, vc_hdlr);
+ PROC.reply(RAN_register:{l3_info, vc_hdlr}) to vc_hdlr;
+ }
+
+ [] PROC.getcall(RAN_register_imsi:{?,?,?}) -> param(imsi, tmsi, vc_hdlr) {
+ f_create_imsi(imsi, tmsi, vc_hdlr);
+ PROC.reply(RAN_register_imsi:{imsi, tmsi, vc_hdlr}) to vc_hdlr;
+ }
+
+
+ }
+ }
+}
+
+private function f_mgcp_ep_extract_cic(charstring inp) return integer {
+ var charstring local_part := regexp(inp, "(*)@*", 0);
+ return hex2int(str2hex(local_part));
+
+}
+
+/***********************************************************************
+ * "Expect" Handling (mapping for expected incoming SCCP connections)
+ ***********************************************************************/
+
+/* data about an expected future incoming connection */
+type record ExpectData {
+ /* L3 payload based on which we can match it */
+ octetstring l3_payload optional,
+ /* component reference for this connection */
+ RAN_ConnHdlr vc_conn
+}
+
+/* procedure based port to register for incoming connections */
+signature RAN_register(in octetstring l3, in RAN_ConnHdlr hdlr);
+
+/* procedure based port to register for incoming IMSI/TMSI */
+signature RAN_register_imsi(in hexstring imsi, in OCT4 tmsi, in RAN_ConnHdlr hdlr);
+
+type port RAN_PROC_PT procedure {
+ inout RAN_register, RAN_register_imsi;
+} with { extension "internal" };
+
+/* CreateCallback that can be used as create_cb and will use the expectation table */
+function ExpectedCreateCallback(BSSAP_N_CONNECT_ind conn_ind, charstring id)
+runs on RAN_Emulation_CT return RAN_ConnHdlr {
+ var RAN_ConnHdlr ret := null;
+ var octetstring l3_info;
+ var integer i;
+
+ if (not ischosen(conn_ind.userData.pdu.bssmap.completeLayer3Information)) {
+ setverdict(fail, "N-CONNECT.ind with L3 != COMPLETE L3");
+ mtc.stop;
+ return ret;
+ }
+ l3_info := conn_ind.userData.pdu.bssmap.completeLayer3Information.layer3Information.layer3info;
+
+ for (i := 0; i < sizeof(ExpectTable); i:= i+1) {
+ if (not ispresent(ExpectTable[i].l3_payload)) {
+ continue;
+ }
+ if (l3_info == ExpectTable[i].l3_payload) {
+ ret := ExpectTable[i].vc_conn;
+ /* release this entry to be used again */
+ ExpectTable[i].l3_payload := omit;
+ ExpectTable[i].vc_conn := null;
+ log("Found Expect[", i, "] for ", l3_info, " handled at ", ret);
+ /* return the component reference */
+ return ret;
+ }
+ }
+ setverdict(fail, "Couldn't find Expect for incoming connection ", conn_ind);
+ mtc.stop;
+ return ret;
+}
+
+private function f_create_expect(octetstring l3, RAN_ConnHdlr hdlr)
+runs on RAN_Emulation_CT {
+ var integer i;
+ for (i := 0; i < sizeof(ExpectTable); i := i+1) {
+ if (not ispresent(ExpectTable[i].l3_payload)) {
+ ExpectTable[i].l3_payload := l3;
+ ExpectTable[i].vc_conn := hdlr;
+ log("Created Expect[", i, "] for ", l3, " to be handled at ", hdlr);
+ return;
+ }
+ }
+ testcase.stop("No space left in ExpectTable");
+}
+
+private function f_create_imsi(hexstring imsi, OCT4 tmsi, RAN_ConnHdlr hdlr)
+runs on RAN_Emulation_CT {
+ for (var integer i := 0; i < sizeof(ImsiTable); i := i+1) {
+ if (not ispresent(ImsiTable[i].imsi)) {
+ ImsiTable[i].imsi := imsi;
+ ImsiTable[i].tmsi := tmsi;
+ ImsiTable[i].comp_ref := hdlr;
+ log("Created IMSI[", i, "] for ", imsi, tmsi, " to be handled at ", hdlr);
+ return;
+ }
+ }
+ testcase.stop("No space left in ImsiTable");
+}
+
+
+private function f_expect_table_init()
+runs on RAN_Emulation_CT {
+ for (var integer i := 0; i < sizeof(ExpectTable); i := i+1) {
+ ExpectTable[i].l3_payload := omit;
+ }
+}
+
+/* helper function for clients to register their IMSI/TMSI */
+function f_ran_register_imsi(hexstring imsi, OCT4 tmsi)
+runs on RAN_ConnHdlr {
+ BSSAP_PROC.call(RAN_register_imsi:{imsi, tmsi, self}) {
+ [] BSSAP_PROC.getreply(RAN_register_imsi:{?,?,?}) {};
+ }
+}
+
+
+}