From 9e0bd808bfe84c3e7d51dbbc01668047d9f7283b Mon Sep 17 00:00:00 2001 From: Matt Johnson Date: Fri, 21 Aug 2020 17:31:57 -0700 Subject: [PATCH] server_cb: Improve handling resynchronization info This commit improves handling of the resynchronization information in a DIAMETER request from a UE that has a sync failure. It factors parsing of the resync info into a helper function with a defined spec, and handles the resynchronization info as a binary rather than a string. Change-Id: I2aad313d4d37d07040bc5344de3a023d34fd8ded --- src/server_cb.erl | 31 ++++++++++++++++++++++++------- 1 file changed, 24 insertions(+), 7 deletions(-) diff --git a/src/server_cb.erl b/src/server_cb.erl index dc7fe59..fc8e397 100644 --- a/src/server_cb.erl +++ b/src/server_cb.erl @@ -100,6 +100,22 @@ req_num_of_vec([#'Requested-UTRAN-GERAN-Authentication-Info'{'Number-Of-Requeste req_num_of_vec([#'Requested-UTRAN-GERAN-Authentication-Info'{'Number-Of-Requested-Vectors'=[Num]}]) -> Num; req_num_of_vec(_) -> false. + +-type binary_or_false() :: false | binary(). +-spec req_resynchronization_info([tuple()]) -> binary_or_false(). +req_resynchronization_info([#'Requested-EUTRAN-Authentication-Info'{'Re-Synchronization-Info'=[]}]) -> + false; +req_resynchronization_info([#'Requested-EUTRAN-Authentication-Info'{'Re-Synchronization-Info'=[Info]}]) -> + list_to_binary(Info); + +req_resynchronization_info([#'Requested-UTRAN-GERAN-Authentication-Info'{'Re-Synchronization-Info'=[]}]) -> + false; +req_resynchronization_info([#'Requested-UTRAN-GERAN-Authentication-Info'{'Re-Synchronization-Info'=[Info]}]) -> + list_to_binary(Info); + +req_resynchronization_info(_) -> + false. + -define(PDP_TYPE_DEFAULT, <<0,0,0,16#21>>). % IPv4 -define(PDP_QOS_DEFAULT, <<0,0,0,0,0,0,0,0,0,0,0,0,0,0>>). % fixme @@ -188,13 +204,14 @@ handle_request(#diameter_packet{msg = Req, errors = []}, _SvcName, {_, Caps}) wh % construct GSUP request to HLR and transceive it GsupTx1 = #{message_type => send_auth_info_req, imsi => list_to_binary(UserName), supported_rat_types => [rat_eutran_sgs], current_rat_type => rat_eutran_sgs}, - case ReqEU of - #'Requested-EUTRAN-Authentication-Info'{'Re-Synchronization-Info' = ReSyncInfo} - when is_binary(ReSyncInfo) -> - GsupTx2 = #{rand => string:substr(ReSyncInfo, 1, 16), - auts => string:substr(ReSyncInfo, 17)}; - _ -> - GsupTx2 = #{} + ResyncInfo = req_resynchronization_info(ReqEU), + case ResyncInfo of + false -> + GsupTx2 = #{}; + ValidResyncInfo -> + lager:info("ResyncInfo is valid ~p", [ResyncInfo]), + GsupTx2 = #{rand => binary:part(ValidResyncInfo, 0, 16), + auts => binary:part(ValidResyncInfo, 16, 14)} end, GsupTx = maps:merge(GsupTx1, GsupTx2), GsupRx = gen_server:call(gsup_client, {transceive_gsup, GsupTx, send_auth_info_res, send_auth_info_err}),