diff options
Diffstat (limited to 'asterisk/IMS_ConnectionHandler.ttcn')
| -rw-r--r-- | asterisk/IMS_ConnectionHandler.ttcn | 1906 |
1 files changed, 1906 insertions, 0 deletions
diff --git a/asterisk/IMS_ConnectionHandler.ttcn b/asterisk/IMS_ConnectionHandler.ttcn new file mode 100644 index 00000000..39abc59c --- /dev/null +++ b/asterisk/IMS_ConnectionHandler.ttcn @@ -0,0 +1,1906 @@ +/* Component implementing a IMS server towards Asterisk's IMS UE + * (C) 2024 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> + * Author: Pau Espin Pedrol <pespin@sysmocom.de> + * All rights reserved. + * + * Released under the terms of GNU General Public License, Version 2 or + * (at your option) any later version. + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ +module IMS_ConnectionHandler { + +import from TCCEncoding_Functions all; +import from TCCOpenSecurity_Functions all; +import from General_Types all; +import from Osmocom_Types all; +import from Native_Functions all; +import from Misc_Helpers all; + +/* the PIPE asp port allows us to interact with ip xfrm via stdin/stdout */ +import from PIPEasp_PortType all; +import from PIPEasp_Types all; +import from PIPEasp_Templates all; + +import from SDP_Types all; +import from SDP_Templates all; + +import from SIP_Emulation all; +import from SIPmsg_Types all; +import from SIP_Templates all; + + +modulepar { + charstring mp_ipsec_setup_script_path := "./IMS_ipsec_setup.sh"; +} + +const integer c_def_expires := 600000; /* 3GPP TS 24.229 5.1.1.2.1 e) */ +const charstring c_sip_server_name := "osmo-ttcn3-hacks/0.23"; + + +type port IMSCoord_PT message +{ + inout charstring; +} with { extension "internal" }; + +const charstring IMS_COORD_CMD_REGISTERED := "IMS_COORD_CMD_REGISTERED"; +const charstring IMS_COORD_CMD_START := "IMS_COORD_CMD_START"; +const charstring IMS_COORD_CMD_CALL_ESTABLISHED := "IMS_COORD_CMD_CALL_ESTABLISHED"; +const charstring IMS_COORD_CMD_HANGUP := "IMS_COORD_CMD_HANGUP"; +const charstring IMS_COORD_CMD_CALL_FINISHED := "IMS_COORD_CMD_CALL_FINISHED"; +const charstring IMS_COORD_CMD_CALL_REJECTED := "IMS_COORD_CMD_CALL_REJECTED"; +const charstring IMS_COORD_CMD_CALL_TRYING := "IMS_COORD_CMD_CALL_TRYING"; +const charstring IMS_COORD_CMD_CALL_SESSION_PROGRESS := "IMS_COORD_CMD_CALL_SESSION_PROGRESS"; +const charstring IMS_COORD_CMD_CALL_SESSION_REFRESH := "IMS_COORD_CMD_CALL_SESSION_REFRESH"; + +type component IMS_ConnHdlr extends SIP_ConnHdlr { + var charstring g_name; + var IMS_ConnHdlrPars g_pars; + timer g_Tguard; + var PDU_SIP_Request g_rx_sip_req; + var PDU_SIP_Response g_rx_sip_resp; + + port IMSCoord_PT COORD; + port PIPEasp_PT PIPE; +} +type record of IMS_ConnHdlr IMS_ConnHdlrList; + +type record IMS_AuthVector { + OCT16 rand, + OCT16 autn, + OCT8 res, + OCT16 ck, + OCT16 ik, + OCT14 auts +} + +type record IMS_ConnHdlrSubscrPars { + charstring remote_sip_host optional, + uint16_t remote_sip_port optional, + charstring imsi, + charstring imei, + charstring display_name, + charstring password, + charstring msisdn, + boolean support_video, + boolean support_smsip, + boolean close_tcp_after_registration, + /* Expected User-Location-Info in P-Access-Network-Info */ + charstring uli_str, + IMS_AuthVector auth, + charstring ipsec_auth_key, + integer ipsec_local_spi_c, + integer ipsec_local_spi_s, + integer ipsec_remote_spi_c optional, + integer ipsec_remote_spi_s optional, + uint16_t ipsec_remote_port_c optional, + uint16_t ipsec_remote_port_s optional, + SipAddr registrar_sip_record, + CallidString registrar_sip_call_id, + integer registrar_sip_seq_nr, + integer exp_uac_expires, + integer registrar_expires, + SipUrl local_sip_url_ext, + SipAddr local_sip_record, + WwwAuthenticate www_auth optional, + Contact registered_contact optional, + P_Associated_Uri p_associated_uri, + IMS_CallPars cp optional +} +type record of IMS_ConnHdlrSubscrPars IMS_ConnHdlrSubscrParsList; + + +type record IMS_ConnHdlrPars { + float t_guard, + charstring realm, + charstring local_sip_host, + uint16_t local_sip_port, + SipUrl registrar_sip_req_uri, + Via local_via, + Server server_name, + IMS_ConnHdlrSubscrPars subscr optional +} +type record of IMS_ConnHdlrPars IMS_ConnHdlrParsList; + +type record IMS_CallParsMO { + /* Whether to COORD.send(IMS_COORD_CMD_CALL_TRYING) when receiving an INVITE from UE. */ + boolean tx_coord_cmd_invite_trying, + /* Whether to announce "Support: timer" and Session-Expires header */ + boolean support_timer_enable, + integer support_timer_session_expires, + integer support_timer_exp_min_se +} +template (value) IMS_CallParsMO t_IMS_CallParsMO := { + tx_coord_cmd_invite_trying := false, + support_timer_enable := false, + support_timer_session_expires := 0, + support_timer_exp_min_se := 0 +} + +type record IMS_CallParsMT { + /* Whether to COORD.send(IMS_COORD_CMD_CALL_SESSION_PROGRESS) when receiving an 183 Session Progress from UE. */ + boolean tx_coord_cmd_session_progress, + /* Whether to announce "Support: timer" and Session-Expires header */ + boolean support_timer_enable, + integer support_timer_session_expires, + integer support_timer_min_se +} +template (value) IMS_CallParsMT t_IMS_CallParsMT := { + tx_coord_cmd_session_progress := false, + support_timer_enable := false, + support_timer_session_expires := 0, + support_timer_min_se := 90 +} + +type record IMS_CallPars { + SipAddr calling optional, + SipAddr called optional, + + From from_addr optional, + To to_addr optional, + + CallidString sip_call_id, + integer sip_seq_nr, + charstring sip_body optional, + + charstring local_rtp_addr, + uint16_t local_rtp_port, + + boolean support_precondition_ext, + boolean require_precondition_ext, + SDP_Message peer_sdp optional, + IMS_CallParsMO mo, + IMS_CallParsMT mt +} + +template (value) IMS_CallPars t_IMS_CallPars(charstring local_rtp_addr, + uint16_t local_rtp_port := 0, + template (omit) SipAddr calling := omit, + template (omit) SipAddr called := omit) := { + calling := calling, + called := called, + from_addr := omit, + to_addr := omit, + sip_call_id := hex2str(f_rnd_hexstring(15)), + sip_seq_nr := f_sip_rand_seq_nr(), + sip_body := omit, + local_rtp_addr := local_rtp_addr, + local_rtp_port := local_rtp_port, + support_precondition_ext := true, + require_precondition_ext := false, + peer_sdp := omit, + mo := t_IMS_CallParsMO, + mt := t_IMS_CallParsMT +} + +template (value) IMS_ConnHdlrSubscrPars t_IMS_SubscrPars(charstring local_sip_host, + uint16_t local_sip_port, + charstring domain, + charstring imsi, + charstring imei, + charstring msisdn := "90828", + charstring display_name := "Anonymous", + charstring password := "secret", + template (omit) IMS_CallPars cp := omit) := { + remote_sip_host := omit, + remote_sip_port := omit, + imsi := imsi, + imei := imei, + display_name := f_sip_str_quote(display_name), + password := password, + msisdn := msisdn, + support_video := false, + support_smsip := false, + close_tcp_after_registration := false, + uli_str := "2380100010000101", + auth := { + /* The Nonce field is the Base64 encoded version of the RAND value and concatenated with the AUTN: */ + rand := 'd5d5de2bce418d7865ed7fa6956618a2'O, + autn := 'd42e61db5f15800067393a5b7691a227'O, + res := '6f2556bbe4366ab1'O, + ck := '0b389d08c833991734936bec55cac800'O, + ik := '17141862125bd30c81c4224391a0909a'O, + /* NOTE: AUTS value randomly crafted. It's fine since it's just forwarded + * AMI -> asterisk -> IMS and we blindly match and accept it. */ + auts := 'd42e61db5f15800067393a5b7691'O + }, + ipsec_auth_key := "0x17141862125bd30c81c4224391a0909a00000000", + ipsec_local_spi_c := 4142, + ipsec_local_spi_s := 4143, + ipsec_remote_spi_c := omit, + ipsec_remote_spi_s := omit, + ipsec_remote_port_c := omit, + ipsec_remote_port_s := omit, + registrar_sip_record := ts_SipAddr(ts_HostPort(domain), + ts_UserInfo(imsi), + f_sip_str_quote(display_name)), + registrar_sip_call_id := hex2str(f_rnd_hexstring(15)) & "@" & domain, + registrar_sip_seq_nr := f_sip_rand_seq_nr(), + exp_uac_expires := c_def_expires, + registrar_expires := c_def_expires, + local_sip_url_ext := ts_SipUrl(ts_HostPort(domain, local_sip_port), + ts_UserInfo(imsi)), + local_sip_record := ts_SipAddr(ts_HostPort(domain), + ts_UserInfo(imsi)), + www_auth := omit, + registered_contact := omit, + p_associated_uri := ts_P_Associated_Uri({}), + cp := cp +} + +template (value) IMS_ConnHdlrPars t_IMS_Pars(charstring local_sip_host, + uint16_t local_sip_port, + charstring domain, + charstring imsi, + charstring imei, + template (omit) IMS_CallPars cp := omit) := { + t_guard := 60.0, + realm := domain, + local_sip_host := local_sip_host, + local_sip_port := local_sip_port, + registrar_sip_req_uri := valueof(ts_SipUrlHost(domain)), + local_via := ts_Via_from(ts_HostPort(local_sip_host, local_sip_port)), + server_name := valueof(ts_Server({c_sip_server_name})), + subscr := t_IMS_SubscrPars(local_sip_host, local_sip_port, + domain := domain, imsi := imsi, + imei := imei, cp := cp) +} + +private altstep as_Tguard() runs on IMS_ConnHdlr { + [] g_Tguard.timeout { + setverdict(fail, "Tguard timeout"); + mtc.stop; + } +} + +type function ims_void_fn(charstring id) runs on IMS_ConnHdlr; +function f_ims_handler_init(ims_void_fn fn, charstring id, IMS_ConnHdlrPars pars) +runs on IMS_ConnHdlr { + g_name := id; + g_pars := pars; + g_Tguard.start(pars.t_guard); + activate(as_Tguard()); + + /* call the user-supied test case function */ + fn.apply(id); +} + +altstep as_SIP_fail_req(charstring exp_msg_str := "") runs on IMS_ConnHdlr +{ + var PDU_SIP_Request sip_req; + [] SIP.receive(PDU_SIP_Request:?) -> value sip_req { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected SIP Req message := ", sip_req, "\nvs exp := ", exp_msg_str)); + } +} + +altstep as_SIP_fail_resp(charstring exp_msg_str := "") runs on IMS_ConnHdlr +{ + var PDU_SIP_Response sip_resp; + [] SIP.receive(PDU_SIP_Response:?) -> value sip_resp { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected SIP Resp message := ", sip_resp, "\nvs exp := ", exp_msg_str)); + } +} + +altstep as_SIP_expect_resp(template (present) PDU_SIP_Response sip_expect, boolean fail_others := true) runs on IMS_ConnHdlr +{ + var charstring sip_expect_str := log2str(sip_expect); + [] SIP.receive(sip_expect) -> value g_rx_sip_resp; + [fail_others] as_SIP_fail_resp(sip_expect_str); + [fail_others] as_SIP_fail_req(sip_expect_str); +} + +altstep as_SIP_ignore_resp(template PDU_SIP_Response sip_expect := ?) runs on IMS_ConnHdlr +{ + [] SIP.receive(sip_expect) -> value g_rx_sip_resp { + log("Ignoring ", g_rx_sip_resp); + repeat; + } +} + +private function f_nonce_from_rand_autn(octetstring rand, octetstring autn) return charstring { + var octetstring concat := rand & autn; + var charstring nonce := enc_MIME_Base64(concat); + log("rand=", rand, " & autn=",autn, " => nonce=", nonce); + return nonce; +} + +/* HTTP Digest Authentication Using AKA (AKAv1-MD5): RFC 3310 */ +function f_tr_Authorization_AKAv1MD5(WwwAuthenticate www_authenticate, + charstring username, + charstring uri) +return template (present) Authorization { + var CommaParam_List digestCln; + var template (present) Authorization authorization; + var template (present) Credentials cred; + var template (omit) GenericParam rx_param; + + digestCln := www_authenticate.challenge[0].digestCln; + + var charstring algorithm := f_sip_param_get_value_present_or_fail(digestCln, "algorithm"); + var charstring realm := f_sip_param_get_value_present_or_fail(digestCln, "realm"); + var charstring nonce := f_sip_param_get_value_present_or_fail(digestCln, "nonce"); + + var template (present) CommaParam_List digestResponse := superset( + tr_Param("username", f_sip_str_quote(username)), + tr_Param("realm", f_sip_str_quote(realm)), + tr_Param("nonce", f_sip_str_quote(nonce)), + tr_Param("uri", f_sip_str_quote(uri)), + tr_Param("response", ?), + tr_Param("algorithm", algorithm), + tr_Param("qop", "auth"), + tr_Param("cnonce", ?), + tr_Param("nc", ?) + ); + cred := tr_Credentials_DigestResponse(digestResponse); + authorization := tr_Authorization(cred); + return authorization; +} + +private function f_ims_validate_Authorization_AKAv1MD5_Response(Authorization authorization, charstring method) +runs on IMS_ConnHdlr { + f_sip_digest_validate_Authorization_AKAv1MD5(authorization, method, g_pars.subscr.auth.res); +} + +/* GSMA IR-92 2.2.1 SIP Registration Procedure */ +private function f_ims_validate_register_contact(Contact rx_contact) runs on IMS_ConnHdlr +{ + /* IMS contact shows up like this: + * Contact: <sip:8adf9f3d-9342-4060-aa4f-a909f37fd6f6@192.168.101.2:5060>;+g.3gpp.accesstype="cellular2";video;audio;+g.3gpp.smsip;+g.3gpp.nw-init-ussi;+g.3gpp.icsi-ref="urn%3Aurn-7%3A3gpp-service.ims.icsi.mmtel";+sip.instance="<urn:gsma:imei:35589811-338445-0>" + */ + if (ischosen(rx_contact.contactBody.wildcard)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected Contact wildcard := ", rx_contact)); + } + var ContactAddress_List caddrs := rx_contact.contactBody.contactAddresses; + if (lengthof(caddrs) == 0) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected empty Contact Address list")); + } + for (var integer i := 0; i < lengthof(caddrs); i := i + 1) { + var ContactAddress caddr := caddrs[i]; + var template (omit) GenericParam param_tpl; + var boolean rx_supported; + if (not ispresent(caddr.contactParams)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected empty Contact attributes (omit)")); + } + f_sip_param_match_value_or_fail(caddr.contactParams, "+g.3gpp.icsi-ref", "\"urn%3Aurn-7%3A3gpp-service.ims.icsi.mmtel\""); + f_sip_param_match_value_or_fail(caddr.contactParams, "+sip.instance", "\"<urn:gsma:imei:" & g_pars.subscr.imei & ">\""); + f_sip_param_match_value_or_fail(caddr.contactParams, "audio", omit); + + /* Check video support */ + param_tpl := f_sip_param_find(caddr.contactParams, "video"); + rx_supported := not istemplatekind(param_tpl, "omit"); + if (rx_supported) { + /* This attribute never has a value: */ + if (not istemplatekind(param_tpl.paramValue, "omit")) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received Contact with 'video' attribute containing a value := ", rx_contact)); + } + if (not g_pars.subscr.support_video) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received Contact with unexpected 'video' attribute := ", rx_contact)); + } + } else if (g_pars.subscr.support_video) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received Contact with missing 'video' attribute := ", rx_contact)); + } + + /* Check smsip support */ + param_tpl := f_sip_param_find(caddr.contactParams, "+g.3gpp.smsip"); + rx_supported := not istemplatekind(param_tpl, "omit"); + if (rx_supported) { + /* This attribute never has a value: */ + if (not istemplatekind(param_tpl.paramValue, "omit")) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received Contact with '+g.3gpp.smsip' attribute containing a value := ", rx_contact)); + } + if (not g_pars.subscr.support_smsip) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received Contact with unexpected '+g.3gpp.smsip' attribute := ", rx_contact)); + } + } else if (g_pars.subscr.support_smsip) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received Contact with missing '+g.3gpp.smsip' attribute := ", rx_contact)); + } + } + +} + +/* Validate P-Access-Network-Info: RFC7315 6.4 */ +private function f_ims_validate_register_P_Access_Network_info(PDU_SIP_Request req, + boolean exp_present := true) runs on IMS_ConnHdlr + +{ + if (not exp_present) { + if (ispresent(g_rx_sip_req.msgHeader.p_access_network_info)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected [rfc7315 6.4] P-Access-Info := ", + g_rx_sip_req.msgHeader.p_access_network_info)); + } + return; + } + + /* exp_present: */ + var template (present) P_Access_Network_Info expl_tmpl := + tr_P_Access_Network_Info({ tr_Access_net_spec_EUTRAN(g_pars.subscr.uli_str) }); + + if (not ispresent(g_rx_sip_req.msgHeader.p_access_network_info)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received no P-Access-Info vs exp := ", + expl_tmpl)); + } + if (not match(g_rx_sip_req.msgHeader.p_access_network_info, expl_tmpl)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected P-Access-Info := ", + g_rx_sip_req.msgHeader.p_access_network_info, + "\nvs exp := ", expl_tmpl)); + } +} + +/* GSMA IR.92 2.2.4 Call Establishment and Termination */ +private function f_ims_validate_INVITE_Contact(Contact rx_contact) runs on IMS_ConnHdlr +{ + /* INVITE Contact header shows up like this: + * Contact: <sip:e05d8e82-8565-47b5-aca5-5f6b9164b074@192.168.101.2:44823>;+g.3gpp.icsi-ref="urn%3Aurn-7%3A3gpp-service.ims.icsi.mmtel";audio;+g.3gpp.mid-call;+g.3gpp.srvcc-alerting;+g.3gpp.ps2cs-srvcc-orig-pre-alerting + */ + if (ischosen(rx_contact.contactBody.wildcard)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected Contact wildcard := ", rx_contact)); + } + var ContactAddress_List caddrs := rx_contact.contactBody.contactAddresses; + if (lengthof(caddrs) == 0) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected empty Contact Address list")); + } + for (var integer i := 0; i < lengthof(caddrs); i := i + 1) { + var ContactAddress caddr := caddrs[i]; + if (not ispresent(caddr.contactParams)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected empty Contact attributes (omit)")); + } + /* GSMA FCM.01 3.2.3.3: "The INVITE request contains Within the Contact header [...] the IMS + * Communication Service Identifier's (ICSI) for IMS Multimedia Telephony" */ + f_sip_param_match_value_or_fail(caddr.contactParams, "+g.3gpp.icsi-ref", "\"urn%3Aurn-7%3A3gpp-service.ims.icsi.mmtel\""); + /* "The UE must include the audio media feature tag, as defined in IETF RFC 3840, + * in the Contact header field of the SIP INVITE request, and in the Contact header + * field of the SIP response to the SIP INVITE request" */ + f_sip_param_match_value_or_fail(caddr.contactParams, "audio", omit); + } +} + +/* Validate P-Preferred-Service: GSMA FCM.01 3.2.3.3 */ +private function f_ims_validate_invite_P_Preferred_Service(PDU_SIP_Request req, + boolean exp_present := true) runs on IMS_ConnHdlr + +{ + if (not exp_present) { + if (ispresent(g_rx_sip_req.msgHeader.p_preferred_service)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected [rfc6050] P-Preferred-Service := ", + g_rx_sip_req.msgHeader.p_preferred_service)); + } + return; + } + + /* exp_present: */ + var template (present) P_Preferred_Service expl_tmpl := + tr_P_Preferred_Service({ "urn:urn-7:3gpp-service.ims.icsi.mmtel" }); + + if (not ispresent(g_rx_sip_req.msgHeader.p_preferred_service)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received no P-Preferred-Service vs exp := ", + expl_tmpl)); + } + if (not match(g_rx_sip_req.msgHeader.p_preferred_service, expl_tmpl)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected P-Preferred-Service := ", + g_rx_sip_req.msgHeader.p_preferred_service, + "\nvs exp := ", expl_tmpl)); + } +} + +/* GSMA IR.92 2.2.4 Call Establishment and Termination */ +private function f_ims_validate_INVITE_SDP(SDP_Message sdp) runs on IMS_ConnHdlr +{ + /* "The UE must indicate in the SDP of the initial INVITE that the audio media + * is send-receive i.e. either by including the direction attribute "a=sendrecv" + * or by omitting the direction attributes. */ + if (ispresent(sdp.attributes)) { + if (match (sdp.attributes, superset(tr_SDP_recvonly)) or + match (sdp.attributes, superset(tr_SDP_sendonly))) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Unexpected SDP direction attribute != sendrecv: ", + sdp.attributes)); + } + } +} + +private function f_ims_parse_security_client(Security_client security_client) runs on IMS_ConnHdlr +{ + var boolean found := false; + for (var integer i := 0; i < lengthof(security_client.sec_mechanism_list); i := i + 1) { + var Security_mechanism sec_mec := security_client.sec_mechanism_list[i]; + if (sec_mec.mechanism_name != "ipsec-3gpp") { + log("Skipping Security Mechansim: ", sec_mec.mechanism_name); + continue; + } + var SemicolonParam_List sec_pars := sec_mec.mechanism_params; + var charstring par_val; + par_val := f_sip_param_get_value_present_or_fail(sec_pars, "alg"); + if (par_val != "hmac-sha-1-96") { + log("Skipping Security Mechansim Algo: ", par_val); + continue; + } + par_val := f_sip_param_get_value_present_or_fail(sec_pars, "spi-c"); + g_pars.subscr.ipsec_remote_spi_c := str2int(par_val); + par_val := f_sip_param_get_value_present_or_fail(sec_pars, "spi-s"); + g_pars.subscr.ipsec_remote_spi_s := str2int(par_val); + par_val := f_sip_param_get_value_present_or_fail(sec_pars, "port-c"); + g_pars.subscr.ipsec_remote_port_c := str2int(par_val); + par_val := f_sip_param_get_value_present_or_fail(sec_pars, "port-s"); + g_pars.subscr.ipsec_remote_port_s := str2int(par_val); + found := true; + break; + } + + if (not found) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & "alg=hmac-sha-1-96 not found: ", security_client)); + } + + log("ipsec: remote_spi_c=", g_pars.subscr.ipsec_remote_spi_c, " remote_spi_s=", g_pars.subscr.ipsec_remote_spi_s, + "local_spi_c=", g_pars.subscr.ipsec_local_spi_c, " local_spi_s=", g_pars.subscr.ipsec_local_spi_s); +} + +private function f_ims_parse_register_contact(Contact contact) runs on IMS_ConnHdlr +{ + var HostPort hp := valueof(contact.contactBody.contactAddresses[0].addressField.nameAddr.addrSpec.hostPort); + + g_pars.subscr.remote_sip_host := hp.host; + if (ispresent(hp.portField)) { + g_pars.subscr.remote_sip_port := hp.portField; + } else { + g_pars.subscr.remote_sip_port := 5060; + } +} + +private function f_IMS_exec_sync(charstring cmdline, template (present) integer rc := 0) + runs on IMS_ConnHdlr return ASP_PResult { + var ASP_PResult res; + + map(self:PIPE, system:PIPE); + res := f_PIPEasp_exec_sync_PResult(PIPE, cmdline, tr_PResult(?, ?, rc)); + unmap(self:PIPE, system:PIPE); + + return res; +} + +private function f_ims_setup_ipsec() runs on IMS_ConnHdlr +{ + var ASP_PResult res; + + var charstring cmd := mp_ipsec_setup_script_path & " " & + g_pars.local_sip_host & " " & + int2str(g_pars.local_sip_port) & " " & int2str(g_pars.subscr.ipsec_local_spi_c) & " " & + int2str(g_pars.local_sip_port) & " " & int2str(g_pars.subscr.ipsec_local_spi_s) & " " & + g_pars.subscr.remote_sip_host & " " & + int2str(g_pars.subscr.ipsec_remote_port_c) & " " & int2str(g_pars.subscr.ipsec_remote_spi_c) & " " & + int2str(g_pars.subscr.ipsec_remote_port_s) & " " & int2str(g_pars.subscr.ipsec_remote_spi_s) & " " & + g_pars.subscr.ipsec_auth_key; + + res := f_IMS_exec_sync(cmd); + + /* Debug applied rules: */ + /* + res := f_IMS_exec_sync("ip xfrm state"); + log("ip-xfrm-state Result-Stdout: " & res.stdout); + + res := f_IMS_exec_sync("ip xfrm policy"); + log("ip-xfrm-policy Result-Stdout: " & res.stdout); + */ +} + +private function f_tr_Via_response(Via via_req) return template (present) Via { + template (present) SemicolonParam_List via_resp_params := ?; + + /*via_resp_params := { + { id := "rport", paramValue := int2str(g_pars.subscr.remote_sip_port.subscr.remote_sip_port) }, + { id := "received", paramValue := g_pars.subscr.remote_sip_host } + }; */ + return tr_Via_from(via_req.viaBody[0].sentBy, + via_req.viaBody[0].sentProtocol.transport, + via_resp_params); +} + +private function f_tr_From(template (value) SipAddr from_req) return template (present) SipAddr { + return tr_SipAddr_from_val(from_req); +} + +private altstep as_SIP_expect_req(template (present) PDU_SIP_Request sip_expect, boolean fail_others := true) runs on IMS_ConnHdlr +{ + var charstring sip_expect_str := log2str(sip_expect); + [] SIP.receive(sip_expect) -> value g_rx_sip_req; + [fail_others] as_SIP_fail_req(sip_expect_str); + [fail_others] as_SIP_fail_resp(sip_expect_str); +} + +type enumerated IMS_gen_sdp_state { + IMS_GEN_SDP_None, + IMS_GEN_SDP_MO_INVITE, + IMS_GEN_SDP_MO_UPDATE, + IMS_GEN_SDP_MT_Session_Progress, + IMS_GEN_SDP_MT_UPDATE_200OK +} + +private function f_gen_sdp(IMS_gen_sdp_state st := IMS_GEN_SDP_None, charstring dir := "sendrecv") runs on IMS_ConnHdlr return charstring { + var charstring sdp := + "v=0\r\n" & + "o=0502 2390 1824 IN IP4 " & g_pars.subscr.cp.local_rtp_addr & "\r\n" & + "s=Talk\r\n" & + "c=IN IP4 " & g_pars.subscr.cp.local_rtp_addr & "\r\n" & + "t=0 0\r\n" & + "a=rtcp-xr:rcvr-rtt=all:10000 stat-summary=loss,dup,jitt,TTL voip-metrics\r\n" & + "a=record:off\r\n" & + "m=audio " & int2str(g_pars.subscr.cp.local_rtp_port) & " RTP/AVP 126 99 100 101\r\n" & + "b=AS:34\r\n" & + "b=RS:600\r\n" & + "b=RR:2000\r\n" & + "a=rtpmap:126 EVS/16000/1\r\n" & + "a=fmtp:126 br=5.9-16.4;bw=nb-fb;max-red=0\r\n" & + "a=rtpmap:99 telephone-event/48000\r\n" & + "a=rtpmap:100 telephone-event/16000\r\n" & + "a=rtpmap:101 telephone-event/8000\r\n" & + "a=rtcp:" & int2str(g_pars.subscr.cp.local_rtp_port + 1) & "\r\n" & + "a=rtcp-fb:* trr-int 1000\r\n" & + "a=rtcp-fb:* ccm tmmbr\r\n" & + "a=ptime:20\r\n" ; + select (st) { + case (IMS_GEN_SDP_None) { + } + case (IMS_GEN_SDP_MO_INVITE) { + sdp := sdp & + "a=curr:qos local none\r\n" & + "a=curr:qos remote none\r\n" & + "a=des:qos mandatory local sendrecv\r\n" & + "a=des:qos optional remote sendrecv\r\n"; + } + case (IMS_GEN_SDP_MO_UPDATE) { + sdp := sdp & + "a=curr:qos local sendrecv\r\n" & + "a=curr:qos remote none\r\n" & + "a=des:qos mandatory local sendrecv\r\n" & + "a=des:qos mandatory remote sendrecv\r\n"; + } + case (IMS_GEN_SDP_MT_Session_Progress) { + sdp := sdp & + "a=curr:qos local none\r\n" & + "a=curr:qos remote none\r\n" & + "a=des:qos mandatory local sendrecv\r\n" & + "a=des:qos mandatory remote sendrecv\r\n" & + "a=conf:qos remote sendrecv\r\n"; + } + case (IMS_GEN_SDP_MT_UPDATE_200OK) { + sdp := sdp & + "a=curr:qos local sendrecv\r\n" & + "a=curr:qos remote sendrecv\r\n" & + "a=des:qos mandatory local sendrecv\r\n" & + "a=des:qos mandatory remote sendrecv\r\n"; + } + } + + sdp := sdp & "a=" & dir & "\r\n"; + return sdp; +} + +private function f_gen_Security_server() runs on IMS_ConnHdlr return Security_server { + var template (value) Security_server security_server; + /* Security-Server: ipsec-3gpp;q=0.1;prot=esp;mod=trans;spi-c=4096;spi-s=4097;port-c=5104;port-s=6104;alg=hmac-sha-1-96;ealg=null */ + var template (value) SemicolonParam_List sec_params := { + ts_Param("q", "0.1"), + ts_Param("prot", "esp"), + ts_Param("mod", "trans"), + ts_Param("spi-c", int2str(g_pars.subscr.ipsec_local_spi_c)), + ts_Param("spi-s", int2str(g_pars.subscr.ipsec_local_spi_s)), + ts_Param("port-c", int2str(g_pars.local_sip_port)), + ts_Param("port-s", int2str(g_pars.local_sip_port)), + ts_Param("alg", "hmac-sha-1-96"), + ts_Param("ealg", "null") + }; + security_server := ts_Security_server({ + ts_Security_mechanism("ipsec-3gpp", sec_params) + }); + return valueof(security_server); +} + +private function f_gen_WwwAuthenticate() runs on IMS_ConnHdlr return WwwAuthenticate { + var template (value) WwwAuthenticate wwwAuthenticate; + var template (value) CommaParam_List digestCln; + digestCln := { + ts_Param("realm", f_sip_str_quote(g_pars.realm)), + ts_Param("qop", f_sip_str_quote("auth")), + ts_Param("algorithm", "AKAv1-MD5"), + ts_Param("nonce", f_sip_str_quote(f_nonce_from_rand_autn(g_pars.subscr.auth.rand, + g_pars.subscr.auth.autn))) + /* "opaque not needed in IMS "*/ + }; + wwwAuthenticate := ts_WwwAuthenticate( { ts_Challenge_digestCln(digestCln) } ); + return valueof(wwwAuthenticate); +} + +type enumerated IMS_register_early_return { + IMS_REG_EARLY_RET_BEFORE_None, + IMS_REG_EARLY_RET_BEFORE_Initial_100Trying, + IMS_REG_EARLY_RET_BEFORE_Initial_401Unauthorized, + IMS_REG_EARLY_RET_BEFORE_Resync_401Unauthorized, + IMS_REG_EARLY_RET_BEFORE_Protected_100Trying, + IMS_REG_EARLY_RET_BEFORE_Protected_200OK +} + +/* Peer is issuing 1st register, accept it: */ +altstep as_IMS_register(boolean exp_auth_resync := false, + IMS_register_early_return early_ret := IMS_REG_EARLY_RET_BEFORE_None, + boolean fail_others := true) runs on IMS_ConnHdlr +{ + var template (present) PDU_SIP_Request exp_req := + tr_SIP_REGISTER(g_pars.registrar_sip_req_uri, + ?, + tr_From(), + tr_To(), + tr_Via_from(?), + expires := tr_Expires(int2str(g_pars.subscr.exp_uac_expires)), + require := tr_Require(superset("sec-agree")), + security_client := tr_Security_client(superset(tr_Security_mechanism("ipsec-3gpp", + superset(tr_Param("alg","hmac-sha-1-96"))))), + supported := tr_Supported(superset("path", "sec-agree"))); + var charstring sip_expect_str := log2str(exp_req); + + [] SIP.receive(exp_req) -> value g_rx_sip_req { + var template (value) PDU_SIP_Response tx_resp; + var Via via; + var CallidString sip_call_id; + var template (value) From from_addr; + var template (value) To to_addr; + var Security_server security_server; + var template (value) Require require := ts_Require({"sec-agree"}); + var template (value) Supported supported := ts_Supported({"sec-agree"}); + var integer sip_seq_nr; + + if (early_ret == IMS_REG_EARLY_RET_BEFORE_Initial_100Trying) { + return; /* Done */ + } + + sip_call_id := g_rx_sip_req.msgHeader.callId.callid; + via := g_rx_sip_req.msgHeader.via; + via.viaBody[0].viaParams := f_sip_param_set(via.viaBody[0].viaParams, "rport", "1234"); /* TODO: set remote src port of the REGISTER */ + from_addr := g_rx_sip_req.msgHeader.fromField; + to_addr := g_rx_sip_req.msgHeader.toField; + sip_seq_nr := g_rx_sip_req.msgHeader.cSeq.seqNumber; + + /* Tx 100 Tyring */ + tx_resp := ts_SIP_Response_Trying(sip_call_id, + from_addr, + to_addr, + via, + sip_seq_nr, + "REGISTER", + allow := omit, + server := g_pars.server_name, + userAgent := omit); + SIP.send(tx_resp); + + /* Validate P-Access-Network-Info: rfc7315 6.4: + * "3GPP will use the P-Access-Network-Info header field to + * carry relatively sensitive information like the cell ID. Therefore, + * the information MUST NOT be sent outside of the 3GPP domain."" + * [...] "the sensitive information carried in the + * P-Access-Network-Info header field MUST NOT be sent in any initial + * unauthenticated and unprotected requests (e.g., REGISTER)." + */ + f_ims_validate_register_P_Access_Network_info(g_rx_sip_req, exp_present := false); + + f_ims_validate_register_contact(g_rx_sip_req.msgHeader.contact); + f_ims_parse_register_contact(g_rx_sip_req.msgHeader.contact); + f_ims_parse_security_client(g_rx_sip_req.msgHeader.security_client); + + if (early_ret == IMS_REG_EARLY_RET_BEFORE_Initial_401Unauthorized) { + return; /* Done */ + } + + if (not exp_auth_resync) { + /* Delay ipsec setup in ip xfrm, since there will be another + * 1st REGISTER with potentially new ports coming in later. */ + f_ims_setup_ipsec(); + } + + to_addr.toParams := f_sip_param_set(to_addr.toParams, "tag", f_sip_rand_tag()); + g_pars.subscr.www_auth := f_gen_WwwAuthenticate(); + security_server := f_gen_Security_server(); + + /* Tx 401 Unauthorized */ + tx_resp := ts_SIP_Response_Unauthorized(sip_call_id, + from_addr, + to_addr, + via, + g_pars.subscr.www_auth, + sip_seq_nr, + "REGISTER", + p_associated_uri := g_pars.subscr.p_associated_uri, + security_server := security_server, + server := g_pars.server_name, + supported := supported, + userAgent := omit); + SIP.send(tx_resp); + + if (exp_auth_resync) { + /* Now we should receive a new non-protected REGISTER + * with Authoritzation containing auts in base64: */ + var template (present) Authorization authorization := + f_tr_Authorization_AKAv1MD5(g_pars.subscr.www_auth, + g_pars.subscr.imsi & "@" & g_pars.realm, + f_sip_SipUrl_to_str(g_pars.registrar_sip_req_uri)); + exp_req := + tr_SIP_REGISTER(g_pars.registrar_sip_req_uri, + ?, + tr_From(), + tr_To(), + tr_Via_from(f_tr_HostPort(via.viaBody[0].sentBy.host, via.viaBody[0].sentBy.portField)), + authorization := authorization); + SIP.receive(exp_req) -> value g_rx_sip_req; + + if (early_ret == IMS_REG_EARLY_RET_BEFORE_Resync_401Unauthorized) { + return; /* Done */ + } + + via := g_rx_sip_req.msgHeader.via; + from_addr := g_rx_sip_req.msgHeader.fromField; + to_addr := g_rx_sip_req.msgHeader.toField; + sip_seq_nr := g_rx_sip_req.msgHeader.cSeq.seqNumber; + + /* Tx 100 Tyring */ + tx_resp := ts_SIP_Response_Trying(sip_call_id, + from_addr, + to_addr, + via, + sip_seq_nr, + "REGISTER", + allow := omit, + server := g_pars.server_name, + userAgent := omit); + SIP.send(tx_resp); + + f_sip_param_match_value_or_fail(g_rx_sip_req.msgHeader.authorization.body.digestResponse, + "auts", f_sip_str_quote(enc_MIME_Base64(g_pars.subscr.auth.auts))); + f_ims_validate_register_P_Access_Network_info(g_rx_sip_req, exp_present := false); + f_ims_validate_register_contact(g_rx_sip_req.msgHeader.contact); + f_ims_parse_register_contact(g_rx_sip_req.msgHeader.contact); + f_ims_parse_security_client(g_rx_sip_req.msgHeader.security_client); + f_ims_setup_ipsec(); + + security_server := f_gen_Security_server(); + to_addr.toParams := f_sip_param_set(to_addr.toParams, "tag", f_sip_rand_tag()); + + /* Tx again 401 Unauthorized, this time our AMI interface will accept it: */ + tx_resp := ts_SIP_Response_Unauthorized(sip_call_id, + from_addr, + to_addr, + via, + g_pars.subscr.www_auth, + sip_seq_nr, + "REGISTER", + p_associated_uri := g_pars.subscr.p_associated_uri, + security_server := security_server, + server := g_pars.server_name, + supported := supported, + userAgent := omit); + SIP.send(tx_resp); + } + + /* Now we should receive a new REGISTER over ipsec: */ + as_IMS_2nd_register(early_ret := early_ret); + } + [fail_others] as_SIP_fail_resp(sip_expect_str); + [fail_others] as_SIP_fail_req(sip_expect_str); + +} + +/* Peer is issuing 2nd register, accept it: */ +altstep as_IMS_2nd_register(IMS_register_early_return early_ret := IMS_REG_EARLY_RET_BEFORE_None, + boolean fail_others := true) runs on IMS_ConnHdlr +{ + var template (present) Authorization authorization := + f_tr_Authorization_AKAv1MD5(g_pars.subscr.www_auth, + g_pars.subscr.imsi & "@" & g_pars.realm, + f_sip_SipUrl_to_str(g_pars.registrar_sip_req_uri)); + var template (present) PDU_SIP_Request exp_req := + tr_SIP_REGISTER(g_pars.registrar_sip_req_uri, + ?, + tr_From(), + tr_To(), + tr_Via_from(f_tr_HostPort(g_pars.subscr.remote_sip_host, g_pars.subscr.ipsec_remote_port_s)), + authorization := authorization); + var charstring sip_expect_str := log2str(exp_req); + + [] SIP.receive(exp_req) -> value g_rx_sip_req { + var template (value) PDU_SIP_Response tx_resp; + var Via via; + var Contact contact; + var CallidString sip_call_id; + var template (value) From from_addr; + var template (value) To to_addr; + var template (value) Require require := ts_Require({"sec-agree"}); + var template (value) Supported supported := ts_Supported({"sec-agree"}); + var integer sip_seq_nr; + + if (early_ret == IMS_REG_EARLY_RET_BEFORE_Protected_100Trying) { + return; /* Done */ + } + + sip_call_id := g_rx_sip_req.msgHeader.callId.callid; + via := g_rx_sip_req.msgHeader.via; + from_addr := g_rx_sip_req.msgHeader.fromField; + to_addr := g_rx_sip_req.msgHeader.toField; + sip_seq_nr := g_rx_sip_req.msgHeader.cSeq.seqNumber; + + /* Tx 100 Trying */ + tx_resp := ts_SIP_Response_Trying(sip_call_id, + from_addr, + to_addr, + via, + sip_seq_nr, + "REGISTER", + allow := omit, + server := g_pars.server_name, + userAgent := omit); + SIP.send(tx_resp); + + /* Validate Digest Response: */ + f_ims_validate_Authorization_AKAv1MD5_Response(g_rx_sip_req.msgHeader.authorization, "REGISTER"); + + /* Validate P-Access-Network-Info: */ + f_ims_validate_register_P_Access_Network_info(g_rx_sip_req, exp_present := true); + + if (early_ret == IMS_REG_EARLY_RET_BEFORE_Protected_200OK) { + return; /* Done */ + } + + g_pars.subscr.p_associated_uri := valueof(ts_P_Associated_Uri({ + ts_P_Assoc_uri_spec(ts_NameAddr(ts_SipUrl(ts_HostPort(g_pars.realm), + ts_UserInfo(g_pars.subscr.msisdn), + scheme := "sip"))), + ts_P_Assoc_uri_spec(ts_NameAddr(ts_SipUrl(ts_HostPort(g_pars.subscr.msisdn), + omit, + scheme := "tel"))), + ts_P_Assoc_uri_spec(g_rx_sip_req.msgHeader.toField.addressField.nameAddr) + })); + + contact := g_rx_sip_req.msgHeader.contact; + f_ims_validate_register_contact(contact); + f_ims_parse_register_contact(contact); + g_pars.subscr.registered_contact := contact; + /* Set expires= to configured value: RFC3261 10.3 8) */ + for (var integer i := 0; i < lengthof(contact.contactBody.contactAddresses); i := i + 1) { + contact.contactBody.contactAddresses[i].contactParams := + valueof({ ts_Param("expires", int2str(g_pars.subscr.registrar_expires)) }); + } + + /* Tx 200 OK */ + to_addr.toParams := f_sip_param_set(to_addr.toParams, "tag", f_sip_rand_tag()); + tx_resp := ts_SIP_Response(sip_call_id, + from_addr, + to_addr, + "REGISTER", 200, + sip_seq_nr, + "OK", + via, + contact := contact, + p_associated_uri := g_pars.subscr.p_associated_uri, + require := require, + server := g_pars.server_name, + supported := supported, + userAgent := omit); + SIP.send(tx_resp); + if (g_pars.subscr.close_tcp_after_registration) { + f_IMS_tcp_close(); + } + } + [fail_others] as_SIP_fail_resp(sip_expect_str); + [fail_others] as_SIP_fail_req(sip_expect_str); +} + +/* Peer wants to unregister, accept it: */ +altstep as_IMS_unregister(boolean fail_others := true) runs on IMS_ConnHdlr +{ + var template (present) PDU_SIP_Request exp_req := + tr_SIP_REGISTER(g_pars.registrar_sip_req_uri, + ?, + tr_From(), + tr_To(), + tr_Via_from(f_tr_HostPort(g_pars.subscr.remote_sip_host, g_pars.subscr.ipsec_remote_port_s)), + expires := tr_Expires(int2str(0)), + require := tr_Require(superset("sec-agree")), + security_client := tr_Security_client(superset(tr_Security_mechanism("ipsec-3gpp", + superset(tr_Param("alg","hmac-sha-1-96"))))), + supported := tr_Supported(superset("path", "sec-agree"))); + var charstring sip_expect_str := log2str(exp_req); + + [] SIP.receive(exp_req) -> value g_rx_sip_req { + var template (value) PDU_SIP_Response tx_resp; + var Via via; + var CallidString sip_call_id; + var Contact contact; + var template (value) From from_addr; + var template (value) To to_addr; + var template (value) CommaParam_List digestCln ; + var template (value) WwwAuthenticate wwwAuthenticate; + var template (value) Security_server security_server; + var template (value) Require require := ts_Require({"sec-agree"}); + var template (value) Supported supported := ts_Supported({"sec-agree"}); + var template (present) Authorization authorization; + var integer sip_seq_nr; + + sip_call_id := g_rx_sip_req.msgHeader.callId.callid; + via := g_rx_sip_req.msgHeader.via; + via.viaBody[0].viaParams := f_sip_param_set(via.viaBody[0].viaParams, "rport", "1234"); /* TODO: set remote src port of the REGISTER */ + from_addr := g_rx_sip_req.msgHeader.fromField; + to_addr := g_rx_sip_req.msgHeader.toField; + sip_seq_nr := g_rx_sip_req.msgHeader.cSeq.seqNumber; + + contact := g_rx_sip_req.msgHeader.contact; + f_ims_validate_register_contact(contact); + + /* Validate P-Access-Network-Info: 3GPP TS 24.229 5.1.2A.1.1 + * "If available to the UE (as defined in the access technology specific annexes for each access technology), the UE shall + * insert a P-Access-Network-Info header field into any request for a dialog, any subsequent request (except CANCEL + * requests) or response (except CANCEL responses) within a dialog or any request for a standalone method (see + * subclause 7.2A.4). Insertion of the P-Access-Network-Info header field into the ACK request is optional." + */ + f_ims_validate_register_P_Access_Network_info(g_rx_sip_req, exp_present := true); + + + /* Tx 100 Tyring */ + tx_resp := ts_SIP_Response_Trying(sip_call_id, + from_addr, + to_addr, + via, + sip_seq_nr, + "REGISTER", + allow := omit, + server := g_pars.server_name, + userAgent := omit); + SIP.send(tx_resp); + + /* Change all Contact parameters to expires=0: */ + for (var integer i := 0; i < lengthof(contact.contactBody.contactAddresses); i := i + 1) { + contact.contactBody.contactAddresses[i].contactParams := valueof({ ts_Param("expires", "0") }); + } + g_pars.subscr.registered_contact := omit; + /* Tx 200 OK */ + to_addr.toParams := f_sip_param_set(to_addr.toParams, "tag", f_sip_rand_tag()); + tx_resp := ts_SIP_Response(sip_call_id, + from_addr, + to_addr, + "REGISTER", 200, + sip_seq_nr, + "OK", + via, + contact := contact, + p_associated_uri := g_pars.subscr.p_associated_uri, + require := require, + server := g_pars.server_name, + supported := supported, + userAgent := omit); + SIP.send(tx_resp); + } + [fail_others] as_SIP_fail_resp(sip_expect_str); + [fail_others] as_SIP_fail_req(sip_expect_str); +} + +private function f_IMS_gen_new_Via() runs on IMS_ConnHdlr return Via +{ + var charstring branch_value; + var Via via := g_pars.local_via; + + branch_value := f_sip_gen_branch(f_sip_Addr_Union_to_str(g_pars.subscr.cp.from_addr.addressField), + f_sip_Addr_Union_to_str(valueof(g_pars.subscr.cp.to_addr.addressField)), + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.sip_seq_nr); + via.viaBody[0].viaParams := f_sip_param_set(via.viaBody[0].viaParams, "branch", branch_value); + return via; +} + +private function f_IMS_mt_call_tx_invite(Via via) runs on IMS_ConnHdlr +{ + var template (value) PDU_SIP_Request req; + var template (present) From from_addr_exp; + var template (present) To to_addr_exp; + var template (omit) Min_SE min_SE := omit; + var template (omit) Session_expires session_expires := omit; + var template (omit) Supported supported := omit; + var OptionTag_List supported_list := {}; + var charstring tx_sdp; + var Contact calling_contact; + + /* RFC 3261 8.1.1.3 From */ + from_addr_exp := tr_From(tr_Addr_Union_from_val(g_pars.subscr.cp.from_addr.addressField), *); + to_addr_exp := tr_To(tr_Addr_Union_from_val(g_pars.subscr.cp.to_addr.addressField), *); + calling_contact := valueof(ts_Contact({ + ts_ContactAddress(g_pars.subscr.cp.calling.addr, omit) + })); + + if (g_pars.subscr.cp.support_precondition_ext) { + /* indicate the support for "reliable provisional response" + * and "preconditions mechanism" */ + supported_list := supported_list & { "100rel", "precondition" }; + tx_sdp := f_gen_sdp(IMS_GEN_SDP_MO_INVITE); + } else { + /* Don't add any preconditions to SDP: */ + tx_sdp := f_gen_sdp(IMS_GEN_SDP_None); + } + + if (g_pars.subscr.cp.mt.support_timer_enable) { + supported_list := supported_list & { "timer" }; + if (g_pars.subscr.cp.mt.support_timer_session_expires > 0) { + session_expires := ts_Session_expires(int2str(g_pars.subscr.cp.mt.support_timer_session_expires)); + min_SE := ts_Min_SE(int2str(g_pars.subscr.cp.mt.support_timer_min_se)); + } + } + + if (lengthof(supported_list) > 0) { + supported := ts_Supported(supported_list); + } + + req := ts_SIP_INVITE(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + via, + calling_contact, + g_pars.subscr.cp.sip_seq_nr, + accept := ts_Accept({ ts_AcceptBody("application/sdp"), ts_AcceptBody("application/3gpp-ims+xml") }), + min_SE := min_SE, + session_expires := session_expires, + supported := supported, + body := tx_sdp); + + SIP.send(req); +} + +/* IMS Core starts a call towards the peer: 3GPP TS 24.229 5.1.3.1 */ +function f_IMS_mt_call_setup() runs on IMS_ConnHdlr +{ + var template (value) PDU_SIP_Request req; + var template (present) PDU_SIP_Response exp; + var template (present) From from_addr_exp; + var template (present) To to_addr_exp; + var Via via; + var template (omit) Require require := omit; + var charstring tx_sdp; + var default d_trying, d_ringing; + var Contact calling_contact, called_contact; + var integer sip_seq_nr; + + /* RFC 3261 8.1.1.3 From */ + g_pars.subscr.cp.from_addr := valueof(ts_From(g_pars.subscr.cp.calling.addr, g_pars.subscr.cp.calling.params)); + g_pars.subscr.cp.from_addr.fromParams := f_sip_param_set(g_pars.subscr.cp.from_addr.fromParams, "tag", f_sip_rand_tag()); + g_pars.subscr.cp.to_addr := valueof(ts_To(g_pars.subscr.cp.called.addr, g_pars.subscr.cp.called.params)); + from_addr_exp := tr_From(tr_Addr_Union_from_val(g_pars.subscr.cp.from_addr.addressField), *); + to_addr_exp := tr_To(tr_Addr_Union_from_val(g_pars.subscr.cp.to_addr.addressField), *); + calling_contact := valueof(ts_Contact({ + ts_ContactAddress(g_pars.subscr.cp.calling.addr, omit) + })); + via := f_IMS_gen_new_Via(); + + f_IMS_mt_call_tx_invite(via); + + sip_seq_nr := g_pars.subscr.cp.sip_seq_nr; + + /* Conditionally match and accept 100 Trying. */ + exp := tr_SIP_Response_Trying(g_pars.subscr.cp.sip_call_id, + from_addr_exp, + to_addr_exp, + f_tr_Via_response(via), + sip_seq_nr, "INVITE"); + d_trying := activate(as_SIP_ignore_resp(exp)); + + if (g_pars.subscr.cp.mt.tx_coord_cmd_session_progress) { + /* Signal used to inform that Dedicated bearer can be established: */ + COORD.send(IMS_COORD_CMD_CALL_SESSION_PROGRESS); + } + + if (g_pars.subscr.cp.require_precondition_ext) { + var template (present) SDP_attribute_list preconds; + /* Rx 183 Session Progress */ + exp := tr_SIP_Response_SessionProgress( + g_pars.subscr.cp.sip_call_id, + from_addr_exp, + to_addr_exp, + f_tr_Via_response(via), + sip_seq_nr, "INVITE", + require := tr_Require(superset("100rel", "precondition")), + rseq := tr_RSeq(?), + body := ?); + alt { + [] SIP.receive(exp) -> value g_rx_sip_resp { + f_SDP_decodeMessage(g_rx_sip_resp.messageBody, g_pars.subscr.cp.peer_sdp); + }; + [] SIP.receive(tr_SIP_Response_Ringing(?, ?, ?)) -> value g_rx_sip_resp { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Expected 183 Session Progress instead of 180 Ringing: ", + g_rx_sip_resp)); + } + } + + /* Validate SDP in Session Progress contains the preconditions: + * a=curr:qos local none + * a=curr:qos remote none + * a=des:qos mandatory local sendrecv + * a=des:qos mandatory remote sendrecv + * a=conf:qos remote sendrecv + */ + preconds := superset( + tr_SDP_curr(c_SDP_PRECON_STATUS_TYPE_local, c_SDP_PRECON_DIR_TAG_none), + tr_SDP_curr(c_SDP_PRECON_STATUS_TYPE_remote, c_SDP_PRECON_DIR_TAG_none), + tr_SDP_des(c_SDP_PRECON_STRENGTH_TAG_mandatory, c_SDP_PRECON_STATUS_TYPE_local, c_SDP_PRECON_DIR_TAG_sendrecv), + tr_SDP_des(c_SDP_PRECON_STRENGTH_TAG_mandatory, c_SDP_PRECON_STATUS_TYPE_remote, c_SDP_PRECON_DIR_TAG_sendrecv), + tr_SDP_conf(c_SDP_PRECON_STATUS_TYPE_remote, c_SDP_PRECON_DIR_TAG_sendrecv)); + if (not ispresent(g_pars.subscr.cp.peer_sdp.media_list[0].attributes) or + not match(g_pars.subscr.cp.peer_sdp.media_list[0].attributes, preconds)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Unexpected precondition attrs in Session Progress : ", + g_pars.subscr.cp.peer_sdp.media_list[0].attributes)); + } + + called_contact := g_rx_sip_resp.msgHeader.contact; + /* Update To with the tags received from peer: */ + g_pars.subscr.cp.to_addr := g_rx_sip_resp.msgHeader.toField; + + /* Tx PRACK */ + req := ts_SIP_PRACK(called_contact.contactBody.contactAddresses[0].addressField.nameAddr.addrSpec, + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + via, + g_rx_sip_resp.msgHeader.cSeq.seqNumber + 1, + rack := ts_RAck(g_rx_sip_resp.msgHeader.rseq.response_num, + g_rx_sip_resp.msgHeader.cSeq.seqNumber, + "INVITE"), + body := omit); + SIP.send(req); + + /* Rx 200 OK (PRACK) */ + exp := tr_SIP_Response(g_pars.subscr.cp.sip_call_id, + from_addr_exp, + to_addr_exp, + f_tr_Via_response(via), + omit, + "PRACK", 200, + g_rx_sip_resp.msgHeader.cSeq.seqNumber + 1, "OK", + body := omit); + as_SIP_expect_resp(exp); + + /* Tx UPDATE */ + tx_sdp := f_gen_sdp(IMS_GEN_SDP_MO_UPDATE); + req := ts_SIP_UPDATE(called_contact.contactBody.contactAddresses[0].addressField.nameAddr.addrSpec, + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + via, + g_rx_sip_resp.msgHeader.cSeq.seqNumber + 1, + contact := calling_contact, + require := ts_Require({"sec-agree", "precondition"}), + body := tx_sdp); + SIP.send(req); + + /* Rx 200 OK (UPDATE) */ + exp := tr_SIP_Response(g_pars.subscr.cp.sip_call_id, + from_addr_exp, + to_addr_exp, + f_tr_Via_response(via), + called_contact, + "UPDATE", 200, + g_rx_sip_resp.msgHeader.cSeq.seqNumber + 1, "OK", + body := ?); + as_SIP_expect_resp(exp); + f_SDP_decodeMessage(g_rx_sip_resp.messageBody, g_pars.subscr.cp.peer_sdp); + + /* Validate SDP in 200 OK (UPDATE) contains the preconditions: + * a=curr:qos local sendrecv + * a=curr:qos remote sendrecv + * a=des:qos mandatory local sendrecv + * a=des:qos mandatory remote sendrecv + */ + preconds := superset( + tr_SDP_curr(c_SDP_PRECON_STATUS_TYPE_local, c_SDP_PRECON_DIR_TAG_sendrecv), + tr_SDP_curr(c_SDP_PRECON_STATUS_TYPE_remote, c_SDP_PRECON_DIR_TAG_sendrecv), + tr_SDP_des(c_SDP_PRECON_STRENGTH_TAG_mandatory, c_SDP_PRECON_STATUS_TYPE_local, c_SDP_PRECON_DIR_TAG_sendrecv), + tr_SDP_des(c_SDP_PRECON_STRENGTH_TAG_mandatory, c_SDP_PRECON_STATUS_TYPE_remote, c_SDP_PRECON_DIR_TAG_sendrecv)); + if (not ispresent(g_pars.subscr.cp.peer_sdp.media_list[0].attributes) or + not match(g_pars.subscr.cp.peer_sdp.media_list[0].attributes, preconds)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Unexpected precondition attrs in 200 OK (UPDATE): ", + g_pars.subscr.cp.peer_sdp.media_list[0].attributes)); + } + + g_pars.subscr.cp.sip_seq_nr := g_rx_sip_resp.msgHeader.cSeq.seqNumber + 1; + } + g_pars.subscr.cp.sip_seq_nr := g_pars.subscr.cp.sip_seq_nr + 1; + + /* Conditionally match and accept 180 Ringing */ + exp := tr_SIP_Response_Ringing(g_pars.subscr.cp.sip_call_id, + from_addr_exp, + to_addr_exp, + f_tr_Via_response(via), + sip_seq_nr, "INVITE"); + d_ringing := activate(as_SIP_ignore_resp(exp)); + + /* Wait for 200 OK (INVITE) answer */ + exp := tr_SIP_Response( + g_pars.subscr.cp.sip_call_id, + from_addr_exp, + to_addr_exp, + f_tr_Via_response(via), + ?, + "INVITE", 200, + sip_seq_nr, "OK", + body := *); + as_SIP_expect_resp(exp, fail_others := false); + + called_contact := g_rx_sip_resp.msgHeader.contact; + + deactivate(d_trying); + deactivate(d_ringing); + + /* Make sure "audio" tag set in Contact header */ + f_ims_validate_INVITE_Contact(g_rx_sip_resp.msgHeader.contact); + + /* Update To with the tags received from peer: */ + g_pars.subscr.cp.to_addr := g_rx_sip_resp.msgHeader.toField; + + /* Transmit ACK */ + req := ts_SIP_ACK(called_contact.contactBody.contactAddresses[0].addressField.nameAddr.addrSpec, + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + via, + g_pars.subscr.cp.sip_seq_nr, + omit); + SIP.send(req); + g_pars.subscr.cp.sip_seq_nr := g_pars.subscr.cp.sip_seq_nr + 1; +} + +/* IMS Core starts a call towards the peer and gets rejected. */ +function f_IMS_mt_call_rejected(template (present) integer exp_status_code := 486, + template (present) charstring exp_reason := "Busy Here") runs on IMS_ConnHdlr +{ + var template (value) PDU_SIP_Request req; + var template (present) PDU_SIP_Response exp; + var default d_trying, d_ringing, d_sessprog; + var Via via; + + g_pars.subscr.cp.from_addr := valueof(ts_From(g_pars.subscr.cp.calling.addr, g_pars.subscr.cp.calling.params)); + g_pars.subscr.cp.from_addr.fromParams := f_sip_param_set(g_pars.subscr.cp.from_addr.fromParams, "tag", f_sip_rand_tag()); + g_pars.subscr.cp.to_addr := valueof(ts_To(g_pars.subscr.cp.called.addr, g_pars.subscr.cp.called.params)); + via := f_IMS_gen_new_Via(); + f_IMS_mt_call_tx_invite(via); + + /* Conditionally match and accept 100 Trying. */ + exp := tr_SIP_Response_Trying(g_pars.subscr.cp.sip_call_id, + ?, ?, + f_tr_Via_response(via), + g_pars.subscr.cp.sip_seq_nr, "INVITE"); + d_trying := activate(as_SIP_ignore_resp(exp)); + /* Conditionally match and accept 183 Session Progress. */ + exp := tr_SIP_Response_SessionProgress(g_pars.subscr.cp.sip_call_id, + ?, ?, + f_tr_Via_response(via), + g_pars.subscr.cp.sip_seq_nr, "INVITE"); + d_sessprog := activate(as_SIP_ignore_resp(exp)); + + /* Wait for 486 Busy Here (INVITE) answer */ + exp := tr_SIP_Response(g_pars.subscr.cp.sip_call_id, + ?, ?, + f_tr_Via_response(via), + *, + "INVITE", exp_status_code, + g_pars.subscr.cp.sip_seq_nr, exp_reason, + body := omit); + as_SIP_expect_resp(exp, fail_others := false); + + deactivate(d_sessprog); + deactivate(d_trying); + + /* Update To with the tags received from peer: */ + g_pars.subscr.cp.to_addr := g_rx_sip_resp.msgHeader.toField; + + /* Transmit ACK */ + req := ts_SIP_ACK(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr), + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + via, + g_pars.subscr.cp.sip_seq_nr, + omit); + SIP.send(req); + g_pars.subscr.cp.sip_seq_nr := g_pars.subscr.cp.sip_seq_nr + 1; +} + +/* Tx BYE: */ +function f_IMS_do_call_hangup() runs on IMS_ConnHdlr +{ + var template (value) PDU_SIP_Request req; + var template (present) PDU_SIP_Response exp_resp; + var Via via := f_IMS_gen_new_Via(); + + /* Transmit ACK */ + req := ts_SIP_BYE(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + via, + g_pars.subscr.cp.sip_seq_nr, + omit); + SIP.send(req); + + /* Wait for OK answer */ + exp_resp := tr_SIP_Response( + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + tr_To(tr_Addr_Union_from_val(g_pars.subscr.cp.to_addr.addressField), *), + f_tr_Via_response(via), + *, + "BYE", 200, + g_pars.subscr.cp.sip_seq_nr, "OK"); + as_SIP_expect_resp(exp_resp); + + g_pars.subscr.cp.sip_seq_nr := g_pars.subscr.cp.sip_seq_nr + 1; +} + +private function f_ConnHdlr_parse_initial_SIP_INVITE(PDU_SIP_Request rx_sip_req) runs on IMS_ConnHdlr +{ + f_SDP_decodeMessage(rx_sip_req.messageBody, g_pars.subscr.cp.peer_sdp); + log("Rx Initial MO INVITE decoded SDP: ", g_pars.subscr.cp.peer_sdp); + + /* Obtain params: */ + g_pars.subscr.cp.sip_call_id := rx_sip_req.msgHeader.callId.callid; + g_pars.subscr.cp.from_addr := rx_sip_req.msgHeader.fromField; + g_pars.subscr.cp.to_addr := rx_sip_req.msgHeader.toField; + g_pars.subscr.cp.to_addr.toParams := f_sip_param_set(g_pars.subscr.cp.to_addr.toParams, "tag", f_sip_rand_tag()); + g_pars.subscr.cp.sip_seq_nr := rx_sip_req.msgHeader.cSeq.seqNumber; +} + +/* Peer is calling us, accept it: */ +altstep as_IMS_mo_call_accept(boolean exp_update_to_direct_rtp := false, + boolean fail_others := true) runs on IMS_ConnHdlr +{ + /* 3GPP TS 24.229 5.1.3.1 Initial INVITE request */ + var template (present) PDU_SIP_Request exp_req := + tr_SIP_INVITE(f_tr_SipUrl_opt_defport(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr)), + ?, + tr_From(tr_Addr_Union_from_val(g_pars.subscr.cp.calling.addr), *), + tr_To(tr_Addr_Union_from_val(g_pars.subscr.cp.called.addr), *), + tr_Via_from(f_tr_HostPort(g_pars.subscr.remote_sip_host, g_pars.subscr.ipsec_remote_port_s)), + ?, + accept := tr_Accept(superset(tr_AcceptBody("application/sdp"), tr_AcceptBody("application/3gpp-ims+xml"))), + p_early_media := tr_P_Early_Media(superset("supported")), + supported := tr_Supported(superset("timer")), + body := ?); + var charstring sip_expect_str := log2str(exp_req); + + [] SIP.receive(exp_req) -> value g_rx_sip_req { + var template (value) PDU_SIP_Response tx_resp; + var Via invite_via; + var template (omit) Require require := omit; + var template (omit) Session_expires session_expires := omit; + var template (omit) Supported supported := omit; + var OptionTag_List supported_list := {}; + var OptionTag_List require_list := {}; + var template (omit) charstring tx_sdp; + var integer invite_seq_nr; + var boolean peer_support_precondition := match(g_rx_sip_req.msgHeader.supported.optionsTags, + superset("100rel", "precondition")); + + /* Obtain params: */ + f_ConnHdlr_parse_initial_SIP_INVITE(g_rx_sip_req); + invite_via := g_rx_sip_req.msgHeader.via; + invite_seq_nr := g_pars.subscr.cp.sip_seq_nr; + + f_ims_validate_register_P_Access_Network_info(g_rx_sip_req, exp_present := true); + f_ims_validate_invite_P_Preferred_Service(g_rx_sip_req, exp_present := true); + f_ims_validate_INVITE_Contact(g_rx_sip_req.msgHeader.contact); + f_ims_validate_INVITE_SDP(g_pars.subscr.cp.peer_sdp); + + if (g_pars.subscr.cp.mo.support_timer_enable) { + supported_list := supported_list & { "timer" }; + if (g_pars.subscr.cp.mo.support_timer_session_expires > 0) { + session_expires := ts_Session_expires(int2str(g_pars.subscr.cp.mo.support_timer_session_expires), + {ts_Param("refresher", "uac")}); + } + } + if (lengthof(supported_list) > 0) { + supported := ts_Supported(supported_list); + } + if (g_pars.subscr.cp.mo.support_timer_exp_min_se > 0) { + if (not ispresent(g_rx_sip_req.msgHeader.min_SE)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Missing 'Min_SE' header in INVITE: ", g_rx_sip_req)); + } + if (str2int(g_rx_sip_req.msgHeader.min_SE.deltaSec) != g_pars.subscr.cp.mo.support_timer_exp_min_se) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Received unexpected Min_SE := ", + g_rx_sip_req.msgHeader.min_SE.deltaSec, + "\nvs exp := ", g_pars.subscr.cp.mo.support_timer_exp_min_se)); + } + } + + if (g_pars.subscr.cp.require_precondition_ext and not peer_support_precondition) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Missing '100rel,precondition' in INVITE Supported header: ", + g_rx_sip_req.msgHeader.supported)); + } + + /* Tx 100 Tyring */ + tx_resp := ts_SIP_Response_Trying(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + invite_via, + g_pars.subscr.cp.sip_seq_nr, + "INVITE", + allow := omit, + server := g_pars.server_name, + userAgent := omit); + SIP.send(tx_resp); + + if (g_pars.subscr.cp.mo.tx_coord_cmd_invite_trying) { + /* Signal used to inform that Dedicated bearer can be established: */ + COORD.send(IMS_COORD_CMD_CALL_TRYING); + } + + /* Use precondition ? */ + if (g_pars.subscr.cp.require_precondition_ext or + (g_pars.subscr.cp.support_precondition_ext and peer_support_precondition)) { + var template (present) SDP_attribute_list preconds; + /* Validate SDP in INVITE contains the preconditions: + * a=curr:qos local none + * a=curr:qos remote none + * a=des:qos mandatory local sendrecv + * a=des:qos optional remote sendrecv + */ + preconds := superset( + tr_SDP_curr(c_SDP_PRECON_STATUS_TYPE_local, c_SDP_PRECON_DIR_TAG_none), + tr_SDP_curr(c_SDP_PRECON_STATUS_TYPE_remote, c_SDP_PRECON_DIR_TAG_none), + tr_SDP_des(c_SDP_PRECON_STRENGTH_TAG_mandatory, c_SDP_PRECON_STATUS_TYPE_local, c_SDP_PRECON_DIR_TAG_sendrecv), + tr_SDP_des(c_SDP_PRECON_STRENGTH_TAG_optional, c_SDP_PRECON_STATUS_TYPE_remote, c_SDP_PRECON_DIR_TAG_sendrecv)); + if (not ispresent(g_pars.subscr.cp.peer_sdp.media_list[0].attributes) or + not match(g_pars.subscr.cp.peer_sdp.media_list[0].attributes, preconds)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Unexpected precondition attrs in INVITE : ", + g_pars.subscr.cp.peer_sdp.media_list[0].attributes, + " vs exp: ", preconds)); + } + + /* Tx 183 Session Progress */ + tx_sdp := f_gen_sdp(IMS_GEN_SDP_MT_Session_Progress); + tx_resp := ts_SIP_Response_SessionProgress(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + invite_via, + g_pars.subscr.cp.sip_seq_nr, + p_early_media := ts_P_Early_Media({"recvonly"}), + rseq := ts_RSeq(1), + body := tx_sdp); + SIP.send(tx_resp); + + /* Rx PRACK */ + exp_req := tr_SIP_PRACK(f_tr_SipUrl_opt_defport(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr)), + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + f_tr_Via_response(invite_via), + g_pars.subscr.cp.sip_seq_nr + 1, + rack := tr_RAck(1, g_pars.subscr.cp.sip_seq_nr, "INVITE"), + body := omit); + as_SIP_expect_req(exp_req); + + /* Tx 200 OK (PRACK) */ + tx_resp := ts_SIP_Response(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + "PRACK", 200, + g_pars.subscr.cp.sip_seq_nr + 1, + "OK", + g_rx_sip_req.msgHeader.via /* PRACK's new branch */, + body := omit); + SIP.send(tx_resp); + + /* Rx UPDATE */ + exp_req := tr_SIP_UPDATE(f_tr_SipUrl_opt_defport(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr)), + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + f_tr_Via_response(invite_via), + g_pars.subscr.cp.sip_seq_nr + 2, + require := tr_Require(superset("sec-agree", "precondition")), + supported := tr_Supported(superset("100rel", "timer")), + body := ?); + as_SIP_expect_req(exp_req); + f_SDP_decodeMessage(g_rx_sip_req.messageBody, g_pars.subscr.cp.peer_sdp); + + /* Validate SDP in UPDATE contains the preconditions: + * a=curr:qos local sendrecv + * a=curr:qos remote none + * a=des:qos mandatory local sendrecv + * a=des:qos mandatory remote sendrecv + */ + preconds := superset( + tr_SDP_curr(c_SDP_PRECON_STATUS_TYPE_local, c_SDP_PRECON_DIR_TAG_sendrecv), + tr_SDP_curr(c_SDP_PRECON_STATUS_TYPE_remote, c_SDP_PRECON_DIR_TAG_none), + tr_SDP_des(c_SDP_PRECON_STRENGTH_TAG_mandatory, c_SDP_PRECON_STATUS_TYPE_local, c_SDP_PRECON_DIR_TAG_sendrecv), + tr_SDP_des(c_SDP_PRECON_STRENGTH_TAG_mandatory, c_SDP_PRECON_STATUS_TYPE_remote, c_SDP_PRECON_DIR_TAG_sendrecv)); + if (not ispresent(g_pars.subscr.cp.peer_sdp.media_list[0].attributes) or + not match(g_pars.subscr.cp.peer_sdp.media_list[0].attributes, preconds)) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Unexpected precondition attrs in UPDATE: ", + g_pars.subscr.cp.peer_sdp.media_list[0].attributes, + " vs exp: ", preconds)); + } + + /* Tx 200 OK (UPDATE) */ + tx_sdp := f_gen_sdp(IMS_GEN_SDP_MT_UPDATE_200OK); + tx_resp := ts_SIP_Response(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + "UPDATE", 200, + g_pars.subscr.cp.sip_seq_nr + 2, + "OK", + g_rx_sip_req.msgHeader.via /* UPDATE's new branch */, + session_expires := session_expires, + supported := supported, + body := tx_sdp); + SIP.send(tx_resp); + + /* Update to latest used seq_nr: */ + g_pars.subscr.cp.sip_seq_nr := g_pars.subscr.cp.sip_seq_nr + 2; + /* 200 OK (INVITE) has no SDP if we use precondition: */ + tx_sdp := omit; + } else { + /* Check no precondition is sent in SDP */ + if (ispresent(g_pars.subscr.cp.peer_sdp.media_list[0].attributes) and + match (g_pars.subscr.cp.peer_sdp.media_list[0].attributes, superset(tr_SDP_curr_present, + tr_SDP_des_present, + tr_SDP_conf_present))) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Unexpected precondition attrs in INVITE: ", + g_pars.subscr.cp.peer_sdp.media_list[0].attributes)); + } + /* 200 OK (INVITE) has SDP if no precondition is used: */ + tx_sdp := f_gen_sdp(); + } + + /* Tx 180 Ringing */ + tx_resp := ts_SIP_Response_Ringing(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + invite_via, + invite_seq_nr); + SIP.send(tx_resp); + + + /* Tx 200 OK */ + if (g_pars.subscr.cp.mo.support_timer_enable) { + require_list := require_list & { "timer" }; + } + if (lengthof(require_list) > 0) { + require := ts_Require(require_list); + } + + tx_sdp := f_gen_sdp(); + tx_resp := ts_SIP_Response(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + "INVITE", 200, + invite_seq_nr, + "OK", + invite_via, + require := require, + session_expires := session_expires, + supported := supported, + body := tx_sdp); + SIP.send(tx_resp); + + /* Wait for ACK */ + exp_req := tr_SIP_ACK(f_tr_SipUrl_opt_defport(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr)), + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + f_tr_Via_response(invite_via), + invite_seq_nr, *); + as_SIP_expect_req(exp_req); + } + [fail_others] as_SIP_fail_resp(sip_expect_str); + [fail_others] as_SIP_fail_req(sip_expect_str); + +} + +/* Call is terminated by peer: */ +altstep as_IMS_exp_call_hangup(template (present) integer exp_seq_nr := ?, boolean fail_others := true) runs on IMS_ConnHdlr +{ + var template (present) PDU_SIP_Request exp_req := + tr_SIP_BYE(f_tr_SipUrl_opt_defport(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr)), + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + tr_Via_from(f_tr_HostPort(g_pars.subscr.remote_sip_host, g_pars.subscr.ipsec_remote_port_s)), + exp_seq_nr); + var charstring sip_expect_str := log2str(exp_req); + + [] SIP.receive(exp_req) -> value g_rx_sip_req { + var template (value) PDU_SIP_Response tx_resp; + var charstring tx_sdp; + var Via via; + + /* Update parameters: */ + g_pars.subscr.cp.sip_seq_nr := g_rx_sip_req.msgHeader.cSeq.seqNumber; + /* "branch" has changed: */ + via := g_rx_sip_req.msgHeader.via; + + /* Tx 200 OK */ + tx_sdp := f_gen_sdp(); + tx_resp := ts_SIP_Response(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + "BYE", 200, + g_pars.subscr.cp.sip_seq_nr, + "OK", + via, + body := tx_sdp); + SIP.send(tx_resp); + } + [fail_others] as_SIP_fail_resp(sip_expect_str); + [fail_others] as_SIP_fail_req(sip_expect_str); +} + +private function f_IMS_answer_call_refresh(PDU_SIP_Request req) runs on IMS_ConnHdlr { + var template (value) PDU_SIP_Response tx_resp; + /* Tx 200 OK response*/ + tx_resp := ts_SIP_Response(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + req.msgHeader.cSeq.method, 200, + req.msgHeader.cSeq.seqNumber, + "OK", + req.msgHeader.via, + session_expires := ts_Session_expires(int2str(g_pars.subscr.cp.mo.support_timer_session_expires), + {ts_Param("refresher", "uac")}), + supported := ts_Supported({"timer"}), + body := omit); + SIP.send(tx_resp); +} +/* Session Timer, RFC 4028 */ +altstep as_IMS_exp_call_refresh() runs on IMS_ConnHdlr +{ + /* RFC4028 section 7.4. It can be either INVITE or UPDATE: */ + var template (present) PDU_SIP_Request exp_req_invite := + tr_SIP_INVITE(f_tr_SipUrl_opt_defport(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr)), + ?, + tr_From(tr_Addr_Union_from_val(g_pars.subscr.cp.calling.addr), *), + tr_To(tr_Addr_Union_from_val(g_pars.subscr.cp.called.addr), *), + tr_Via_from(f_tr_HostPort(g_pars.subscr.remote_sip_host, g_pars.subscr.ipsec_remote_port_s)), + ?, + supported := tr_Supported(superset("timer")), + body := *); + + var template (present) PDU_SIP_Request exp_req_update := + tr_SIP_UPDATE(f_tr_SipUrl_opt_defport(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr)), + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + tr_Via_from(f_tr_HostPort(g_pars.subscr.remote_sip_host, g_pars.subscr.ipsec_remote_port_s)), + ?, + body := *); + + [] SIP.receive(exp_req_invite) -> value g_rx_sip_req { + f_IMS_answer_call_refresh(g_rx_sip_req); + g_pars.subscr.cp.sip_seq_nr := g_rx_sip_req.msgHeader.cSeq.seqNumber; + } + [] SIP.receive(exp_req_update) -> value g_rx_sip_req { + f_IMS_answer_call_refresh(g_rx_sip_req); + g_pars.subscr.cp.sip_seq_nr := g_rx_sip_req.msgHeader.cSeq.seqNumber; + } +} + +private altstep as_IMS_exp_call_holdresume(template (present) SDP_attribute exp_dir := tr_SDP_sendonly, + charstring tx_dir := "recvonly") runs on IMS_ConnHdlr +{ + /* RFC4028 section 7.4. It can be either INVITE or UPDATE: */ + var template (present) PDU_SIP_Request exp_req_invite := + tr_SIP_INVITE(f_tr_SipUrl_opt_defport(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr)), + ?, + tr_From(tr_Addr_Union_from_val(g_pars.subscr.cp.calling.addr), *), + tr_To(tr_Addr_Union_from_val(g_pars.subscr.cp.called.addr), *), + tr_Via_from(f_tr_HostPort(g_pars.subscr.remote_sip_host, g_pars.subscr.ipsec_remote_port_s)), + ?, + body := ?); + + [] SIP.receive(exp_req_invite) -> value g_rx_sip_req { + var template (present) PDU_SIP_Request exp_req; + var template (value) PDU_SIP_Response tx_resp; + var charstring tx_sdp; + + f_SDP_decodeMessage(g_rx_sip_req.messageBody, g_pars.subscr.cp.peer_sdp); + g_pars.subscr.cp.sip_seq_nr := g_rx_sip_req.msgHeader.cSeq.seqNumber; + + /* Check a=$exp_dir in SDP */ + if (not ispresent(g_pars.subscr.cp.peer_sdp.media_list[0].attributes) or + not match (g_pars.subscr.cp.peer_sdp.media_list[0].attributes, superset(exp_dir))) { + Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, + log2str(g_name & ": Expected re-INVITE SDP attribute a=", exp_dir, " in: ", + g_pars.subscr.cp.peer_sdp.media_list[0].attributes)); + } + + tx_sdp := f_gen_sdp(dir := tx_dir); + /* Tx 200 OK response*/ + tx_resp := ts_SIP_Response(g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + g_rx_sip_req.msgHeader.cSeq.method, 200, + g_rx_sip_req.msgHeader.cSeq.seqNumber, + "OK", + g_rx_sip_req.msgHeader.via, + body := tx_sdp); + SIP.send(tx_resp); + + /* Wait for ACK */ + exp_req := tr_SIP_ACK(f_tr_SipUrl_opt_defport(ts_SipUrl_from_Addr_Union(g_pars.subscr.cp.called.addr)), + g_pars.subscr.cp.sip_call_id, + g_pars.subscr.cp.from_addr, + g_pars.subscr.cp.to_addr, + f_tr_Via_response(g_rx_sip_req.msgHeader.via), + g_rx_sip_req.msgHeader.cSeq.seqNumber, + body := omit); + as_SIP_expect_req(exp_req); + } +} +altstep as_IMS_exp_call_hold() runs on IMS_ConnHdlr +{ + [] as_IMS_exp_call_holdresume(tr_SDP_sendonly, "recvonly"); +} +altstep as_IMS_exp_call_resume() runs on IMS_ConnHdlr +{ + [] as_IMS_exp_call_holdresume(tr_SDP_sendrecv, "sendrecv"); +} + +function f_IMS_tcp_close() runs on IMS_ConnHdlr +{ + var ASP_SIP_close v_close:={addr:={ + remote_host := g_pars.subscr.remote_sip_host, + remote_port := g_pars.subscr.ipsec_remote_port_c, + local_host := g_pars.local_sip_host, + local_port := g_pars.local_sip_port, + protocol := TCP_E + }} + log("Closing TCP connection: ", v_close); + SIP.send(v_close); +} + +} |