initial check-in of HSS related 3GPP DIAMETER definitions
... including those dependencies I couldn't find
diff --git a/dia/diameter_3gpp_ts29_173.dia b/dia/diameter_3gpp_ts29_173.dia
new file mode 100644
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+++ b/dia/diameter_3gpp_ts29_173.dia
@@ -0,0 +1,134 @@
+;;
+;; %CopyrightBegin%
+;;
+;; Copyright (C) 2019 by Harald Welte. All Rights Reserved.
+;;
+;; This resembles 3GPP TS 29.173 version 15.0.0 Release 15
+;;
+;; Licensed under the Apache License, Version 2.0 (the "License");
+;; you may not use this file except in compliance with the License.
+;; You may obtain a copy of the License at
+;;
+;; http://www.apache.org/licenses/LICENSE-2.0
+;;
+;; Unless required by applicable law or agreed to in writing, software
+;; distributed under the License is distributed on an "AS IS" BASIS,
+;; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+;; See the License for the specific language governing permissions and
+;; limitations under the License.
+;;
+;; %CopyrightEnd%
+;;
+
+;;
+;; Edits:
+;;
+;;
+
+@id 16777291
+@name diameter_3gpp_ts29_173
+@prefix diameter_aaa
+@vendor 10415 3GPP
+
+@inherits diameter_gen_base_rfc6733
+;; @inherits diameter_rfc4005_nasreq
+;; @inherits diameter_rfc4006_cc
+@inherits diameter_3gpp_base
+;; @inherits diameter_etsi_es283_034
+;; @inherits diameter_3gpp_ts29_061_gmb
+;; @inherits diameter_3gpp_ts29_214
+@inherits diameter_3gpp_ts29_229
+@inherits diameter_3gpp_ts29_329
+
+;;@inherits diameter_rfc5447
+;;@inherits diameter_rfc5778
+;;@inherits diameter_3gpp_ts29_272
+
+@avp_types
+
+ 3GPP-AAA-Server-Name 318 DiameterIdentity MV ;; from 29.273
+ SGSN-Number 1489 OctetString MV ;; from 29.272
+ GMLC-Number 1474 OctetString MV ;; from 29.272
+
+ LMSI 2400 OctetString MV
+ Serving-Node 2401 Grouped MV
+ MME-Name 2402 DiameterIdentity MV
+ MSC-Number 2403 OctetString MV
+ LCS-Capabilities-Sets 2404 Unsigned32 MV
+ GMLC-Address 2405 Address MV
+ Additional-Serving-Node 2406 Grouped MV
+ PPR-Address 2407 Address MV
+ MME-Realm 2408 DiameterIdentity V
+ SGSN-Name 2409 DiameterIdentity V
+ SGSN-Realm 2410 DiameterIdentity V
+ RIA-Flags 2411 Unsigned32 V
+
+@messages
+
+ ;; 6.2.3 LCS-Routing-Info-Request
+ RIR ::= < Diameter Header: 8388622, REQ, PXY >
+ < Session-Id >
+ { Auth-Session-State }
+ { Origin-Host }
+ { Origin-Realm }
+ { Destination-Realm }
+ [ Vendor-Specific-Application-Id ]
+ [ Destination-Host ]
+ [ User-Name ]
+ [ MSISDN ]
+ [ GMLC-Number ]
+ *[ Supported-Features ]
+ *[ Proxy-Info ]
+ *[ Route-Record ]
+ *[ AVP ]
+
+ ;; 6.2.4 LCS-Routing-Info-Answer
+ RIA ::= < Diameter Header: 8388622, PXY >
+ < Session-Id >
+ { Auth-Session-State }
+ { Origin-Host }
+ { Origin-Realm }
+ [ Vendor-Specific-Application-Id ]
+ [ Result-Code ]
+ [ Experimental-Result ]
+ *[ Supported-Features ]
+ [ User-Name ]
+ [ MSISDN ]
+ [ LMSI ]
+ [ Serving-Node ]
+ *[ Additional-Serving-Node ]
+ [ GMLC-Address ]
+ [ PPR-Address ]
+ [ RIA-Flags ]
+ *[ AVP ]
+ [ Failed-AVP ]
+ *[ Proxy-Info ]
+ *[ Route-Record ]
+
+@grouped
+
+;; 6.4.3
+Serving-Node ::= <AVP Header: 2401 10415>
+ [ SGSN-Number ]
+ [ SGSN-Name ]
+ [ SGSN-Realm ]
+ [ MME-Name ]
+ [ MME-Realm ]
+ [ MSC-Number ]
+ [ 3GPP-AAA-Server-Name ]
+ [ LCS-Capabilities-Sets ]
+ [ GMLC-Address ]
+ *[AVP]
+
+;; 6.4.8
+Additional-Serving-Node ::= <AVP Header: 2406 10415>
+ [ SGSN-Number ]
+ [ MME-Name ]
+ [ SGSN-Name ]
+ [ SGSN-Realm ]
+ [ MME-Realm ]
+ [ MSC-Number ]
+ [ 3GPP-AAA-Server-Name ]
+ [ LCS-Capabilities-Sets ]
+ [ GMLC-Address ]
+ *[AVP]