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Diffstat (limited to 'library/rua/RUA_Emulation.ttcn')
| -rw-r--r-- | library/rua/RUA_Emulation.ttcn | 404 |
1 files changed, 404 insertions, 0 deletions
diff --git a/library/rua/RUA_Emulation.ttcn b/library/rua/RUA_Emulation.ttcn new file mode 100644 index 00000000..a9c445e0 --- /dev/null +++ b/library/rua/RUA_Emulation.ttcn @@ -0,0 +1,404 @@ +module RUA_Emulation { + +/* RUA_Emulation runs on top of Iuh_Emulation. It multiplexes/demultiplexes + * the individuao connections, so there can be separate TTCN-3 components + * handling each of the connections (one connection per UE). + * + * The RUA_Emulation.main() function processes RUA messages from the Iuh stack + * via the RUA_PT, and dispatches them to the per-connection components. + * + * Outbound RUA connections are initiated by sending a FIXME primitive to the + * RUA_Emulation component. + * + * For each new inbound connection, the RuaOps.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 future inbound connection, + * it can do so by registering an "expect" with the expected RANAP payload. + + * (C) 2022 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 Iuh_Emulation all; + +import from RUA_Templates all; +//import from RUA_Constants all; +import from RUA_PDU_Descriptions all; +import from RUA_IEs all; + +import from RANAP_PDU_Descriptions all; +//import from RANAP_Constants all; +import from RANAP_IEs all; +import from RANAP_Types all; +import from RANAP_Templates all; + +modulepar { + integer mp_max_context_id := hex2int('FFFFFF'H); +} + + +/* General "base class" component definition, of which specific implementations + * derive themselves by means of the "extends" feature */ +type component RUA_ConnHdlr { + port RUA_Conn_PT RUA; +} + +/* port between individual per-connection components and this dispatcher */ +type port RUA_Conn_PT message { + inout RANAP_PDU, + RUA_Conn_Req, + RUA_Disc_Req, + RUA_Disc_Ind; +} with { extension "internal" }; + +type record RUA_Conn_Req { + boolean ps_domain, + RANAP_PDU ranap +}; + +type record RUA_Disc_Req { + RANAP_PDU ranap, + RUA_IEs.Cause cause +}; + +type record RUA_Disc_Ind { + RUA_IEs.Cause cause +}; + +type bitstring ContextId length(24); // with { variant "FIELDLENGTH(24)" }; + +/* represents a single RANAP connection over RUA */ +type record ConnectionData { + RUA_ConnHdlr comp_ref, + RUA_IEs.CN_DomainIndicator domain, + integer context_id +} + +type component RUA_Emulation_CT { + /* port to the bottom side (Iuh) */ + port RUA_PT RUA; + + /* ports to the upper side (per-connection components) */ + port RUA_Conn_PT CLIENT; + + /* 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 RUA_PROC_PT PROC; + + var charstring g_rua_id; + var RuaOps g_rua_ops; +} + +type function RanapCreateCallback(ContextId context_id, RUA_IEs.CN_DomainIndicator domain, charstring id) +runs on RUA_Emulation_CT return RUA_ConnHdlr; + +type function RanapUnitdataCallback(RANAP_PDU ranap) +runs on RUA_Emulation_CT return template RANAP_PDU; + +type record RuaOps { + RanapCreateCallback create_cb optional, + RanapUnitdataCallback unitdata_cb optional + //boolean deode_dtap + //boolean role_ms +}; + +private function f_context_id_known(ContextId context_id) +runs on RUA_Emulation_CT return boolean { + var integer i; + for (i := 0; i < sizeof(ConnectionTable); i := i+1) { + if (ConnectionTable[i].context_id == bit2int(context_id)){ + return true; + } + } + return false; +} + +private function f_comp_known(RUA_ConnHdlr client) +runs on RUA_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; +} + +/* resolve connection ID by component reference */ +private function f_context_id_by_comp(RUA_ConnHdlr client) +runs on RUA_Emulation_CT return ContextId { + for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) { + if (ConnectionTable[i].comp_ref == client) { + return int2bit(ConnectionTable[i].context_id, 24); + } + } + setverdict(fail, "RAN Connection table not found by component ", client); + mtc.stop; +} + +/* resolve ConnectionTable index component reference */ +private function f_idx_by_comp(RUA_ConnHdlr client) +runs on RUA_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_context_id() +runs on RUA_Emulation_CT return ContextId { + var ContextId context_id; + + do { + context_id := int2bit(float2int(rnd()*int2float(mp_max_context_id)), 24); + } while (f_context_id_known(context_id) == true); + + return context_id; +} + +private function f_conn_table_init() +runs on RUA_Emulation_CT { + for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) { + ConnectionTable[i].comp_ref := null; + ConnectionTable[i].context_id := -1; + } +/* + 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(RUA_ConnHdlr comp_ref, RUA_IEs.CN_DomainIndicator domain, ContextId context_id) +runs on RUA_Emulation_CT { + var integer int_context_id := bit2int(context_id); + for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) { + if (ConnectionTable[i].context_id == -1) { + ConnectionTable[i].comp_ref := comp_ref; + ConnectionTable[i].domain := domain; + ConnectionTable[i].context_id := int_context_id; + log("Added conn table entry ", i, comp_ref, int_context_id); + return; + } + } + testcase.stop("RUA Connection table full!"); +} + +private function f_conn_table_del(ContextId context_id) +runs on RUA_Emulation_CT { + var integer int_context_id := bit2int(context_id); + for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) { + if (ConnectionTable[i].context_id == int_context_id) { + log("Deleted conn table entry ", i, + ConnectionTable[i].comp_ref, int_context_id); + ConnectionTable[i].context_id := -1; + return + } + } + setverdict(fail, "RUA Connection table attempt to delete non-existant ", int_context_id); + mtc.stop; +} + + +/* resolve component reference by connection ID */ +private function f_comp_by_context_id(ContextId context_id) +runs on RUA_Emulation_CT return RUA_ConnHdlr { + var integer int_context_id := bit2int(context_id); + for (var integer i := 0; i < sizeof(ConnectionTable); i := i+1) { + if (ConnectionTable[i].context_id == int_context_id) { + return ConnectionTable[i].comp_ref; + } + } + setverdict(fail, "RUA Connection table not found by RUA Context ID ", int_context_id); + mtc.stop; +} + +private function CommonRanapUnitdataCallback(RANAP_PDU ranap) +runs on RUA_Emulation_CT return template RANAP_PDU { + /* TODO: paging */ + return g_rua_ops.unitdata_cb.apply(ranap); +} + +private function f_handle_userData_RANAP(RUA_ConnHdlr client, RANAP_PDU ranap) +runs on RUA_Emulation_CT { + /* TODO: L3 decoding, if requested */ + CLIENT.send(ranap) to client; +} + + +private altstep as_reset_ack() runs on RUA_Emulation_CT { + var RUA_PDU rua_clt; + [] RUA.receive(tr_RUA_ConnectionlessTransfer(decmatch tr_RANAP_Reset)) -> value rua_clt { + var RANAP_PDU rx := dec_RANAP_PDU(rua_clt.initiatingMessage.value_.connectionlessTransfer.protocolIEs[0].value_.rANAP_Message); + var RANAP_IEs.CN_DomainIndicator dom; + dom := rx.initiatingMessage.value_.Reset.protocolIEs[1].value_.cN_DomainIndicator; + RUA.send(ts_RUA_ConnectionlessTransfer(enc_RANAP_PDU(valueof(ts_RANAP_ResetAck(dom))))); + } +} + +private altstep as_main_rua() runs on RUA_Emulation_CT { + var RANAP_PDU ranap; + var RUA_PDU rua; + var octetstring ranap_enc; + var ContextId context_id; + var RUA_IEs.CN_DomainIndicator domain_ind; + var RUA_ConnHdlr vc_conn; + var RUA_Conn_Req creq; + var RUA_Disc_Req dreq; + var RUA_IEs.Cause cause; + + /* RUA -> Client: UNIT-DATA (connectionless RUA) from CN */ + [] RUA.receive(tr_RUA_ConnectionlessTransfer) -> value rua { + ranap := dec_RANAP_PDU(rua.initiatingMessage.value_.connectionlessTransfer.protocolIEs[0].value_.rANAP_Message); + var template RANAP_PDU resp; + resp := CommonRanapUnitdataCallback(ranap); + if (isvalue(resp)) { + RUA.send(ts_RUA_ConnectionlessTransfer(enc_RANAP_PDU(valueof(resp)))); + } + } + + /* RUA -> Client: new connection from CN */ + [] RUA.receive(tr_RUA_Connect) -> value rua { + domain_ind := rua.initiatingMessage.value_.connect_.protocolIEs[0].value_.cN_DomainIndicator; + context_id := rua.initiatingMessage.value_.connect_.protocolIEs[1].value_.context_ID; + ranap_enc := rua.initiatingMessage.value_.connect_.protocolIEs[3].value_.rANAP_Message; + ranap := dec_RANAP_PDU(ranap_enc); + vc_conn := g_rua_ops.create_cb.apply(context_id, domain_ind, g_rua_id); + /* store mapping between client components and RUA contextId */ + f_conn_table_add(vc_conn, domain_ind, context_id); + /* TODO: notify user about incoming connection? */ + /* handle user payload */ + f_handle_userData_RANAP(vc_conn, ranap); + } + + /* RUA -> Client: connection-oriented data in existing connection */ + [] RUA.receive(tr_RUA_DirectTransfer) -> value rua { + context_id := rua.initiatingMessage.value_.directTransfer.protocolIEs[1].value_.context_ID; + vc_conn := f_comp_by_context_id(context_id); + ranap_enc := rua.initiatingMessage.value_.directTransfer.protocolIEs[2].value_.rANAP_Message; + f_handle_userData_RANAP(vc_conn, dec_RANAP_PDU(ranap_enc)); + } + + /* RUA -> Client: disconnect of an existing connection */ + [] RUA.receive(tr_RUA_Disconnect_opt_ranap) -> value rua { + cause := rua.initiatingMessage.value_.disconnect_.protocolIEs[2].value_.cause; + context_id := rua.initiatingMessage.value_.disconnect_.protocolIEs[1].value_.context_ID; + vc_conn := f_comp_by_context_id(context_id); + /* send contained RANAP message to user */ + if (lengthof(rua.initiatingMessage.value_.disconnect_.protocolIEs) > 3) { + ranap_enc := rua.initiatingMessage.value_.disconnect_.protocolIEs[3].value_.rANAP_Message; + f_handle_userData_RANAP(vc_conn, dec_RANAP_PDU(ranap_enc)); + } + /* notify user of disconnect */ + if (CLIENT.checkstate("Connected")) { + CLIENT.send(RUA_Disc_Ind:{cause}); + } + f_conn_table_del(context_id); + } + + /* RANAP from client through an existing RANAP connection */ + [] CLIENT.receive(RANAP_PDU:?) -> value ranap sender vc_conn { + var integer idx := f_idx_by_comp(vc_conn); + context_id := int2bit(ConnectionTable[idx].context_id, 24); + domain_ind := ConnectionTable[idx].domain; + RUA.send(ts_RUA_DirectTransfer(domain_ind, context_id, enc_RANAP_PDU(ranap))); + } + + /* Disconnect request from client */ + [] CLIENT.receive(RUA_Disc_Req:?) -> value dreq sender vc_conn { + var octetstring enc_ranap := enc_RANAP_PDU(dreq.ranap); + var integer idx := f_idx_by_comp(vc_conn); + context_id := int2bit(ConnectionTable[idx].context_id, 24); + domain_ind := ConnectionTable[idx].domain; + RUA.send(ts_RUA_Disconnect(domain_ind, context_id, dreq.cause, enc_ranap)); + f_conn_table_del(context_id); + } + + /* RANAP from client, for a new RANAP connection */ + [] CLIENT.receive(RUA_Conn_Req:?) -> value creq sender vc_conn { + var octetstring enc_ranap := enc_RANAP_PDU(creq.ranap); + + if (f_comp_known(vc_conn) == false) { + /* unknown client, create new connection */ + context_id := f_gen_context_id(); + if (creq.ps_domain) { + domain_ind := ps_domain; + } else { + domain_ind := cs_domain; + } + + f_conn_table_add(vc_conn, domain_ind, context_id); + RUA.send(ts_RUA_Connect(domain_ind, context_id, normal_call, enc_ranap)); + } else { + /* known client, send via existing component */ + context_id := f_context_id_by_comp(vc_conn); + RUA.send(ts_RUA_DirectTransfer(domain_ind, context_id, enc_ranap)); + } + } + +} + + + +function f_ranap_reset(RANAP_IEs.CN_DomainIndicator dom) runs on RUA_Emulation_CT { + timer T := 5.0; + + var RANAP_PDU tx := valueof(ts_RANAP_Reset(ts_RanapCause_om_intervention,dom)); + RUA.send(ts_RUA_ConnectionlessTransfer(enc_RANAP_PDU(tx))); + T.start; + alt { + [] RUA.receive(tr_RUA_ConnectionlessTransfer(decmatch tr_RANAP_ResetAck)) { + log("RUA-RANAP: Received RESET-ACK in response to RESET, we're reay to go!"); + } + [] as_reset_ack(); + [] RUA.receive { repeat; } + [] T.timeout { + setverdict(fail, "RUA-RANAP: Timeout waiting for RESET-ACK after sending RESET"); + mtc.stop; + } + } +} + +function main(RuaOps ops, charstring id) runs on RUA_Emulation_CT { + g_rua_id := id; + g_rua_ops := ops; + f_conn_table_init(); + //f_expect_table_init(); + + while (true) { + alt { + [] as_main_rua(); + + /* + [] PROC.getcall(RUA_Register:{?,?}) -> param(l3_info, vc_hdlr) { + f_create_expect(l3_info, vc_hdlr); + PROC.reply(RUA_register:{l3_info, vc_hdlr}) to vc_hdlr; + } + */ + } + } +} + + +} |