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Diffstat (limited to 'library/RAN_Emulation.ttcnpp')
| -rw-r--r-- | library/RAN_Emulation.ttcnpp | 903 |
1 files changed, 903 insertions, 0 deletions
diff --git a/library/RAN_Emulation.ttcnpp b/library/RAN_Emulation.ttcnpp new file mode 100644 index 0000000..e091133 --- /dev/null +++ b/library/RAN_Emulation.ttcnpp @@ -0,0 +1,903 @@ +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) 2017-2019 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 IPA_Emulation all; +import from MobileL3_Types all; + +#ifdef RAN_EMULATION_BSSAP +import from BSSAP_Types all; +import from BSSAP_CodecPort all; +import from BSSMAP_Templates all; +#endif + +#ifdef RAN_EMULATION_MGCP +import from MGCP_Types all; +import from MGCP_Templates all; +#endif + +/* 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 +} + +/* 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 +} + +/* port between individual per-connection components and this dispatcher */ +type port RAN_Conn_PT message { + inout +#ifdef RAN_EMULATION_BSSAP + PDU_BSSAP, + /* Client requests us to create SCCP Connection */ + BSSAP_Conn_Req, +#endif +#ifdef RAN_EMULATION_MGCP + /* MGCP, only used for IPA SCCPlite (MGCP in IPA mux) */ + MgcpCommand, MgcpResponse, +#endif + /* direct DTAP messages from/to clients */ + PDU_DTAP_MO, PDU_DTAP_MT, + /* misc indications / requests between SCCP and client */ + RAN_Conn_Prim; +} 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, +#ifdef RAN_EMULATION_MGCP + /* most recent MGCP transaction ID (Used on MSC side) */ + MgcpTransId mgcp_trans_id optional, +#endif + /* 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 ports on the bottom side, using ASP primitives */ +#ifdef RAN_EMULATION_BSSAP + port BSSAP_CODEC_PT BSSAP; +#endif + /* BSSAP port to the per-connection clients */ + port RAN_Conn_PT CLIENT; +#ifdef RAN_EMULATION_MGCP + /* MGCP port */ + port IPA_MGCP_PT MGCP; +#endif + + /* 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; +} + + +#ifdef RAN_EMULATION_MGCP +/* 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; +} +#endif + +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; +#ifdef RAN_EMULATION_MGCP + ConnectionTable[i].mgcp_trans_id := omit; +#endif + 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; +} + +#ifdef RAN_EMULATION_BSSAP +type record BSSAP_Conn_Req { + SCCP_PAR_Address addr_peer, + SCCP_PAR_Address addr_own, + PDU_BSSAP bssap +} +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 +}; + +/* 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); +} + +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; + } + } +} + +private function f_bssap_l3_is_rr(PDU_BSSAP bssap) return boolean { + var template octetstring l3 := f_bssap_extract_l3(bssap); + return f_L3_is_rr(l3); +} +#endif + + + +type enumerated RanProtocol { + RAN_PROTOCOL_BSSAP +} + +type record RanOps { +#ifdef RAN_EMULATION_BSSAP + BssmapCreateCallback create_cb optional, + BssmapUnitdataCallback unitdata_cb optional, +#endif + boolean decode_dtap, + boolean role_ms, + RanProtocol protocol, + /* 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); + +private function f_L3_is_rr(template octetstring l3) return boolean { + 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; +} + +/* 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 altstep as_reset_ack() runs on RAN_Emulation_CT { +#ifdef RAN_EMULATION_BSSAP + var BSSAP_N_UNITDATA_ind ud_ind; +#endif +#ifdef RAN_EMULATION_BSSAP + [] 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; + } +#endif +} + + +private altstep as_main_bssap() runs on RAN_Emulation_CT { +#ifdef RAN_EMULATION_BSSAP + 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 PDU_BSSAP bssap; + var RAN_ConnHdlr vc_conn; + + /* 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 := g_ran_ops.create_cb.apply(conn_ind, g_ran_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); + } + } + [] 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)); + } + + /* 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"); + } + + } +#else + [false] CLIENT.receive(false) {} +#endif +} + +private altstep as_main_mgcp() runs on RAN_Emulation_CT { +#ifdef RAN_EMULATION_MGCP + var MgcpCommand mgcp_req; + var MgcpResponse mgcp_resp; + var RAN_ConnHdlr vc_conn; + + /* 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; + } +#else + [false] CLIENT.receive {} +#endif +} + +/* send a raw (encoded) L3 message over given SCCP connection */ +private function f_xmit_raw_l3(integer sccp_conn_id, OCT1 dlci, octetstring l3_enc) runs on RAN_Emulation_CT +{ + select (g_ran_ops.protocol) { +#ifdef RAN_EMULATION_BSSAP + case (RAN_PROTOCOL_BSSAP) { + var PDU_BSSAP bssap; + bssap := valueof(ts_BSSAP_DTAP(l3_enc, dlci)); + BSSAP.send(ts_BSSAP_DATA_req(sccp_conn_id, bssap)); + } +#endif + } +} + +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 RAN_ConnHdlr vc_conn; + var PDU_DTAP_MO dtap_mo; + var PDU_DTAP_MT dtap_mt; + var RAN_ConnHdlr vc_hdlr; + var octetstring l3_info; + var hexstring imsi; + var OCT4 tmsi; + + alt { + [g_ran_ops.protocol == RAN_PROTOCOL_BSSAP] as_main_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); + } + f_xmit_raw_l3(ConnectionTable[idx].sccp_conn_id, dtap_mo.dlci, l3_enc); + } + + [not g_ran_ops.role_ms] CLIENT.receive(PDU_DTAP_MT:?) -> value dtap_mt 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_NW_MS(dtap_mt.dtap); + f_xmit_raw_l3(ConnectionTable[idx].sccp_conn_id, dtap_mt.dlci, l3_enc); + } + + [] as_main_mgcp(); + + [] 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; + } + + + } + } +} + +#ifdef RAN_EMULATION_MGCP +private function f_mgcp_ep_extract_cic(charstring inp) return integer { + var charstring local_part := regexp(inp, "(*)@*", 0); + return hex2int(str2hex(local_part)); + +} +#endif + +/*********************************************************************** + * "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:{?,?,?}) {}; + } +} + + +} |