pespin has submitted this change. ( https://gerrit.osmocom.org/c/erlang/osmo-epdg/+/34896?usp=email ) Change subject: s2b: Implement GTPv2C DeleteBearerReq ...................................................................... s2b: Implement GTPv2C DeleteBearerReq Sessions are now stored/kept upon CreateSession time until deleted through DeleteBearerReq. Related: OS#6046 Change-Id: I1e5af1ead17385d2e494f4c90ffe6455aee850da --- M src/epdg_gtpc_s2b.erl 1 file changed, 137 insertions(+), 26 deletions(-) Approvals: Jenkins Builder: Verified laforge: Looks good to me, approved diff --git a/src/epdg_gtpc_s2b.erl b/src/epdg_gtpc_s2b.erl index 82985a5..a5658f1 100644 --- a/src/epdg_gtpc_s2b.erl +++ b/src/epdg_gtpc_s2b.erl @@ -70,7 +70,9 @@ rport :: non_neg_integer(), restart_counter :: 0..255, seq_no :: 0..16#ffffffff, - sess_list %% TODO: fill it, list of gtp_session + next_local_control_tei = 1 :: 0..16#ffffffff, + next_local_data_tei = 1 :: 0..16#ffffffff, + sessions = sets:new() }). -record(gtp_bearer, { @@ -134,36 +136,45 @@ gen_server:call(?SERVER, {gtpc_create_session_req, {Imsi}}). -handle_call({gtpc_create_session_req, {Imsi}}, _From, State) -> - Sess = new_gtp_session(Imsi, State), - Req = gen_create_session_request(Sess, State), +handle_call({gtpc_create_session_req, {Imsi}}, _From, State0) -> + {Sess0, State1} = find_or_new_gtp_session(Imsi, State0), + Req = gen_create_session_request(Sess0, State1), %TODO: increment State.seq_no. - tx_gtp(Req, State), + tx_gtp(Req, State1), lager:debug("Waiting for CreateSessionResponse~n", []), receive {udp, _Socket, IP, InPortNo, RxMsg} -> try Resp = gtp_packet:decode(RxMsg), - logger:info("s2b: Rx from IP ~p port ~n ~p~n", [IP, InPortNo, Resp]), - %% TODO: store Sess in State. - {reply, {ok, Resp}, State} + lager:info("s2b: Rx from IP ~p port ~p ~p~n", [IP, InPortNo, Resp]), + Sess1 = update_gtp_session_from_create_session_response(Resp, Sess0), + lager:info("s2b: Updated Session after create_session_response: ~p~n", [Sess1]), + State2 = update_gtp_session(Sess0, Sess1, State1), + {reply, {ok, Resp}, State2} catch Any -> - logger:error("Error sending message to receiver, ERROR: ~p~n", [Any]), - {reply, {error, decode_failure}, State} + lager:error("Error sending message to receiver, ERROR: ~p~n", [Any]), + {reply, {error, decode_failure}, State1} end after 5000 -> - logger:error("Timeout waiting for CreateSessionResponse for ~p~n", [Req]), - {reply, timeout, State} + lager:error("Timeout waiting for CreateSessionResponse for ~p~n", [Req]), + {reply, timeout, State1} end. %% @callback gen_server handle_cast(stop, State) -> {stop, normal, State}; -handle_cast(_Req, State) -> +handle_cast(Req, State) -> + lager:info("S2b handle_cast: ~p ~n", [Req]), {noreply, State}. %% @callback gen_server -handle_info(_Info, State) -> +handle_info({udp, _Socket, IP, InPortNo, RxMsg}, State) -> + lager:info("S2b: Rx from IP ~p port ~p: ~p~n", [IP, InPortNo, RxMsg]), + Req = gtp_packet:decode(RxMsg), + lager:info("S2b: Rx from IP ~p port ~p: ~p~n", [IP, InPortNo, Req]), + rx_gtp(Req, State); +handle_info(Info, State) -> + lager:info("S2b handle_info: ~p ~n", [Info]), {noreply, State}. %% @callback gen_server @@ -185,6 +196,76 @@ %% Internal Function Definitions %% ------------------------------------------------------------------ +new_gtp_session(Imsi, State) -> + % TODO: find non-used local TEI inside State + Bearer = #gtp_bearer{ + ebi = 5, + local_data_tei = State#gtp_state.next_local_data_tei + }, + Sess = #gtp_session{imsi = Imsi, + apn = ?APN, + local_control_tei = State#gtp_state.next_local_control_tei, + bearer = Bearer + }, + NewSt = State#gtp_state{next_local_control_tei = State#gtp_state.next_local_control_tei + 1, + next_local_data_tei = State#gtp_state.next_local_data_tei + 1, + sessions = sets:add_element(Sess, State#gtp_state.sessions)}, + {Sess, NewSt}. + +% returns Sess if found, undefined it not +find_gtp_session_by_imsi(Imsi, State) -> + sets:fold( + fun(SessIt = #gtp_session{imsi = Imsi}, _AccIn) -> SessIt; + (_, AccIn) -> AccIn + end, + undefined, + State#gtp_state.sessions). + +find_or_new_gtp_session(Imsi, State) -> + Sess = find_gtp_session_by_imsi(Imsi, State), + case Sess of + #gtp_session{imsi = Imsi} -> + {Sess, State}; + undefined -> + new_gtp_session(Imsi, State) + end. + +update_gtp_session(OldSess, NewSess, State) -> + SetRemoved = sets:del_element(OldSess, State#gtp_state.sessions), + SetUpdated = sets:add_element(NewSess, SetRemoved), + State#gtp_state{sessions = SetUpdated}. + +delete_gtp_session(Sess, State) -> + SetRemoved = sets:del_element(Sess, State#gtp_state.sessions), + State#gtp_state{sessions = SetRemoved}. + +update_gtp_session_from_create_session_response_ie(none, Sess) -> + Sess; +update_gtp_session_from_create_session_response_ie({_, + #v2_fully_qualified_tunnel_endpoint_identifier{ + interface_type = _Interface, + key = TEI, ipv4 = _IP4, ipv6 = _IP6}, + Next}, Sess) -> + update_gtp_session_from_create_session_response_ie(maps:next(Next), Sess#gtp_session{remote_control_tei = TEI}); +update_gtp_session_from_create_session_response_ie({_, _, Next}, + Sess) -> + update_gtp_session_from_create_session_response_ie(maps:next(Next), Sess). + +update_gtp_session_from_create_session_response_ies(#gtp{ie = IEs}, Sess) -> + update_gtp_session_from_create_session_response_ie(maps:next(maps:iterator(IEs)), Sess). + +update_gtp_session_from_create_session_response(Resp = #gtp{version = v2, type = create_session_response}, Sess) -> + update_gtp_session_from_create_session_response_ies(#gtp{ie = Resp#gtp.ie}, Sess). + +% returns Sess if found, undefined it not +find_gtp_session_by_local_teic(LocalControlTei, State) -> + sets:fold( + fun(SessIt = #gtp_session{local_control_tei = LocalControlTei}, _AccIn) -> SessIt; + (_, AccIn) -> AccIn + end, + undefined, + State#gtp_state.sessions). + %% connect/2 connect(Name, {Socket, RemoteAddr, RemotePort}) -> lager:info("~s connecting to IP ~s port ~p~n", [Name, RemoteAddr, RemotePort]), @@ -193,23 +274,27 @@ connect(Address) -> connect(?SVC_NAME, Address). +rx_gtp(Req = #gtp{version = v2, type = delete_bearer_request}, State) -> + Sess = find_gtp_session_by_local_teic(Req#gtp.tei, State), + case Sess of + undefined -> + lager:error("Rx unknown TEI ~p: ~p~n", [Req#gtp.tei, Req]), + {noreply, State}; + Sess -> + Resp = gen_delete_bearer_response(Req, Sess, request_accepted, State), + tx_gtp(Resp, State), + State1 = delete_gtp_session(Sess, State), + {noreply, State1} + end; +rx_gtp(Req, State) -> + lager:error("S2b: UNIMPLEMENTED Rx: ~p~n", [Req]), + {noreply, State}. + tx_gtp(Req, State) -> lager:info("s2b: Tx ~p~n", [Req]), Msg = gtp_packet:encode(Req), gen_udp:send(State#gtp_state.socket, State#gtp_state.raddr, State#gtp_state.rport, Msg). -new_gtp_session(Imsi, _State) -> - % TODO: find non-used local TEI inside State - Bearer = #gtp_bearer{ - ebi = 5, - local_data_tei = 1 - }, - #gtp_session{imsi = Imsi, - apn = ?APN, - local_control_tei = 0, - bearer = Bearer - }. - %% 7.2.1 Create Session Request gen_create_session_request(#gtp_session{imsi = Imsi, apn = Apn, @@ -249,4 +334,17 @@ ], #gtp{version = v2, type = create_session_request, tei = 0, seq_no = SeqNo, ie = IEs}. +gen_delete_bearer_response(Req = #gtp{version = v2, type = delete_bearer_request}, + Sess = #gtp_session{remote_control_tei = RemoteCtlTEI}, + GtpCause, + #gtp_state{restart_counter = RCnt}) -> + IEs = [#v2_recovery{restart_counter = RCnt}, + #v2_cause{v2_cause = GtpCause} + ], + #gtp{version = v2, + type = delete_bearer_response, + tei = RemoteCtlTEI, + seq_no = Req#gtp.seq_no, + ie = IEs}. + -- To view, visit https://gerrit.osmocom.org/c/erlang/osmo-epdg/+/34896?usp=email To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: erlang/osmo-epdg Gerrit-Branch: master Gerrit-Change-Id: I1e5af1ead17385d2e494f4c90ffe6455aee850da Gerrit-Change-Number: 34896 Gerrit-PatchSet: 1 Gerrit-Owner: pespin <pespin(a)sysmocom.de> Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: fixeria <vyanitskiy(a)sysmocom.de> Gerrit-Reviewer: laforge <laforge(a)osmocom.org> Gerrit-Reviewer: lynxis lazus <lynxis(a)fe80.eu> Gerrit-Reviewer: pespin <pespin(a)sysmocom.de> Gerrit-MessageType: merged