fixeria has uploaded this change for review.
s1gw: add UE multiplex component
The UEMux is built upon the ConnHdlr component, allowing to simulate
concurrent activity of multiple virtual UEs. This new component will
be used in follow-up patches.
Change-Id: I60e6f5d2b9882c27cecd06a2450bda4909c0532a
Related: SYS#7288
---
A s1gw/S1GW_UEMux.ttcn
1 file changed, 327 insertions(+), 0 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-ttcn3-hacks refs/changes/50/39850/1
diff --git a/s1gw/S1GW_UEMux.ttcn b/s1gw/S1GW_UEMux.ttcn
new file mode 100644
index 0000000..228cf10
--- /dev/null
+++ b/s1gw/S1GW_UEMux.ttcn
@@ -0,0 +1,327 @@
+module S1GW_UEMux {
+
+/* UE Multiplexer, runs on top of ConnHdlr component, dispatches S1AP PDUs
+ * to/from the UE components. In order to receive S1AP PDUs, a UE component
+ * needs to subscribe for MME_UE_S1AP_ID and/or ENB_UE_S1AP_ID.
+ *
+ * (C) 2025 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * Author: Vadim Yanitskiy <vyanitskiy@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
+ */
+
+import from General_Types all;
+import from Osmocom_Types all;
+
+import from S1AP_IEs all;
+import from S1AP_Types all;
+import from S1AP_PDU_Contents all;
+import from S1AP_PDU_Descriptions all;
+import from S1AP_Utils all;
+import from S1GW_ConnHdlr all;
+
+private type enumerated S1AP_PDU_DIR {
+ S1AP_PDU_DIR_FROM_MME,
+ S1AP_PDU_DIR_FROM_ENB
+};
+
+private type record S1AP_dPDU {
+ S1AP_PDU_DIR dir,
+ S1AP_PDU pdu
+};
+
+private altstep as_s1ap_dpdu(out S1AP_PDU pdu,
+ template (present) S1AP_PDU_DIR dir := ?,
+ template (present) S1AP_PDU tr_pdu := ?)
+runs on UEMuxUE {
+ var S1AP_dPDU dpdu;
+
+ [] UEMUX_CONN.receive(S1AP_dPDU:{dir, tr_pdu}) -> value dpdu {
+ pdu := dpdu.pdu;
+ }
+}
+
+type port UEMUX_CONN_PT message {
+ inout S1AP_dPDU;
+} with { extension "internal" };
+
+type component UEMuxUE {
+ port UEMUX_CONN_PT UEMUX_CONN;
+ port UEMUX_PROC_PT UEMUX_PROC;
+};
+
+type component UEMux_CT extends ConnHdlr, UEMuxUE {
+ /* registered UE components */
+ var UE_ConnList g_uemux_list := { };
+};
+
+
+/* represents a single UE connection */
+private type record UE_ConnData {
+ UEMuxUE vc_conn,
+ MME_UE_S1AP_ID mme_ue_id optional,
+ ENB_UE_S1AP_ID enb_ue_id optional
+};
+private type record of UE_ConnData UE_ConnList;
+
+/***********************************************************************************
+ * UE connection management API
+ **********************************************************************************/
+
+/* find a UE connection [index] by an MME_UE_S1AP_ID */
+private function f_UEMux_find_ue_by_mme_ue_id(MME_UE_S1AP_ID mme_ue_id)
+runs on UEMux_CT return integer {
+ for (var integer i := 0; i < lengthof(g_uemux_list); i := i + 1) {
+ if (g_uemux_list[i].mme_ue_id == mme_ue_id) {
+ return i;
+ }
+ }
+
+ return -1;
+}
+
+/* find a UE connection [index] by an ENB_UE_S1AP_ID */
+private function f_UEMux_find_ue_by_enb_ue_id(ENB_UE_S1AP_ID enb_ue_id)
+runs on UEMux_CT return integer {
+ for (var integer i := 0; i < lengthof(g_uemux_list); i := i + 1) {
+ if (g_uemux_list[i].enb_ue_id == enb_ue_id) {
+ return i;
+ }
+ }
+
+ return -1;
+}
+
+/* find a UE connection [index] for the given S1AP PDU */
+private function f_UEMux_find_ue_for_pdu(in S1AP_PDU pdu)
+runs on UEMux_CT return integer {
+ var template (omit) MME_UE_S1AP_ID mme_ue_id;
+ var template (omit) ENB_UE_S1AP_ID enb_ue_id;
+ var integer idx;
+
+ mme_ue_id := f_S1AP_get_MME_UE_S1AP_ID(pdu);
+ if (isvalue(mme_ue_id)) {
+ idx := f_UEMux_find_ue_by_mme_ue_id(valueof(mme_ue_id));
+ if (idx != -1) {
+ return idx;
+ }
+ }
+
+ enb_ue_id := f_S1AP_get_ENB_UE_S1AP_ID(pdu);
+ if (isvalue(enb_ue_id)) {
+ idx := f_UEMux_find_ue_by_enb_ue_id(valueof(enb_ue_id));
+ if (idx != -1) {
+ return idx;
+ }
+ }
+
+ return -1;
+}
+
+/* find a UE connection [index] by component reference */
+private function f_UEMux_find_ue_by_vc_conn(UEMuxUE vc_conn)
+runs on UEMux_CT return integer {
+ for (var integer i := 0; i < lengthof(g_uemux_list); i := i + 1) {
+ if (g_uemux_list[i].vc_conn == vc_conn) {
+ return i;
+ }
+ }
+
+ return -1;
+}
+
+private function f_UEMux_route_pdu(S1AP_dPDU dpdu)
+runs on UEMux_CT {
+ var integer idx;
+
+ idx := f_UEMux_find_ue_for_pdu(dpdu.pdu);
+ if (idx >= 0) {
+ UEMUX_CONN.send(dpdu) to g_uemux_list[idx].vc_conn;
+ } else {
+ log("S1AP PDU cannot be routed: ", dpdu.pdu);
+ }
+}
+
+/* add a new UE connection, return its index */
+private function f_UEMux_ue_add(UEMuxUE vc_conn)
+runs on UEMux_CT return integer {
+ var integer idx;
+
+ idx := f_UEMux_find_ue_by_vc_conn(vc_conn);
+ if (idx != -1) { /* already registered */
+ return idx;
+ }
+
+ idx := lengthof(g_uemux_list);
+ g_uemux_list[idx] := { vc_conn, omit, omit };
+ log("UE ", vc_conn, " is registered (idx=", idx, ")");
+
+ return idx;
+}
+
+/* subscribe a UE component for S1AP PDUs with the given MME-UE-ID */
+private function f_UEMux_subscribe_for_mme_ue_id(UEMuxUE vc_conn,
+ MME_UE_S1AP_ID mme_ue_id)
+runs on UEMux_CT {
+ var integer idx;
+
+ if (f_UEMux_find_ue_by_mme_ue_id(mme_ue_id) != -1) {
+ setverdict(fail, "MME-UE-ID ", mme_ue_id," is already used");
+ mtc.stop;
+ }
+
+ idx := f_UEMux_ue_add(vc_conn);
+ g_uemux_list[idx].mme_ue_id := mme_ue_id;
+}
+
+/* subscribe a UE component for S1AP PDUs with the given ENB-UE-ID */
+private function f_UEMux_subscribe_for_enb_ue_id(UEMuxUE vc_conn,
+ ENB_UE_S1AP_ID enb_ue_id)
+runs on UEMux_CT {
+ var integer idx;
+
+ if (f_UEMux_find_ue_by_enb_ue_id(enb_ue_id) != -1) {
+ setverdict(fail, "ENB-UE-ID ", enb_ue_id," is already used");
+ mtc.stop;
+ }
+
+ idx := f_UEMux_ue_add(vc_conn);
+ g_uemux_list[idx].enb_ue_id := enb_ue_id;
+}
+
+/* unsubscribe a UE component */
+private function f_UEMux_unsubscribe(UEMuxUE vc_conn)
+runs on UEMux_CT {
+ var UE_ConnList ue_list := { };
+
+ for (var integer i := 0; i < lengthof(g_uemux_list); i := i + 1) {
+ if (g_uemux_list[i].vc_conn != vc_conn) {
+ ue_list := ue_list & { g_uemux_list[i] };
+ }
+ }
+
+ if (lengthof(ue_list) == lengthof(g_uemux_list)) {
+ setverdict(fail, "UE ", vc_conn, " is not known");
+ mtc.stop;
+ }
+
+ g_uemux_list := ue_list;
+ log("UE ", vc_conn, " is unregistered");
+}
+
+signature UEMux_subscribe_for_mme_ue_id(in MME_UE_S1AP_ID mme_ue_id);
+signature UEMux_subscribe_for_enb_ue_id(in ENB_UE_S1AP_ID enb_ue_id);
+signature UEMux_unsubscribe();
+
+type port UEMUX_PROC_PT procedure {
+ inout UEMux_subscribe_for_mme_ue_id;
+ inout UEMux_subscribe_for_enb_ue_id;
+ inout UEMux_unsubscribe;
+} with { extension "internal" };
+
+/***********************************************************************************
+ * public API
+ **********************************************************************************/
+
+function f_UEMuxUE_subscribe_for_mme_ue_id(MME_UE_S1AP_ID mme_ue_id)
+runs on UEMuxUE {
+ UEMUX_PROC.call(UEMux_subscribe_for_mme_ue_id:{mme_ue_id}) {
+ [] UEMUX_PROC.getreply(UEMux_subscribe_for_mme_ue_id:{mme_ue_id});
+ }
+}
+
+function f_UEMuxUE_subscribe_for_enb_ue_id(ENB_UE_S1AP_ID enb_ue_id)
+runs on UEMuxUE {
+ UEMUX_PROC.call(UEMux_subscribe_for_enb_ue_id:{enb_ue_id}) {
+ [] UEMUX_PROC.getreply(UEMux_subscribe_for_enb_ue_id:{enb_ue_id});
+ }
+}
+
+function f_UEMuxUE_unsubscribe()
+runs on UEMuxUE {
+ UEMUX_PROC.call(UEMux_unsubscribe:{}) {
+ [] UEMUX_PROC.getreply(UEMux_unsubscribe:{});
+ }
+}
+
+function f_UEMuxUE_tx_s1ap_from_mme(template (value) S1AP_PDU pdu)
+runs on UEMuxUE {
+ var S1AP_dPDU dpdu := { S1AP_PDU_DIR_FROM_MME, valueof(pdu) };
+ UEMUX_CONN.send(dpdu);
+}
+
+function f_UEMuxUE_tx_s1ap_from_enb(template (value) S1AP_PDU pdu)
+runs on UEMuxUE {
+ var S1AP_dPDU dpdu := { S1AP_PDU_DIR_FROM_ENB, valueof(pdu) };
+ UEMUX_CONN.send(dpdu);
+}
+
+altstep as_UEMuxUE_s1ap_from_mme(out S1AP_PDU pdu,
+ template (present) S1AP_PDU tr_pdu := ?)
+runs on UEMuxUE {
+ [] as_s1ap_dpdu(pdu, S1AP_PDU_DIR_FROM_MME, tr_pdu);
+}
+
+altstep as_UEMuxUE_s1ap_from_enb(out S1AP_PDU pdu,
+ template (present) S1AP_PDU tr_pdu := ?)
+runs on UEMuxUE {
+ [] as_s1ap_dpdu(pdu, S1AP_PDU_DIR_FROM_ENB, tr_pdu);
+}
+
+type function void_fn2(charstring id) runs on UEMux_CT;
+
+function f_UEMux_init(void_fn2 fn, charstring id, ConnHdlrPars pars)
+runs on UEMux_CT {
+ g_pars := pars;
+ fn.apply(id);
+}
+
+function main() runs on UEMux_CT {
+ while (true) {
+ var MME_UE_S1AP_ID mme_ue_id;
+ var ENB_UE_S1AP_ID enb_ue_id;
+ var UEMuxUE vc_conn;
+ var S1AP_PDU pdu;
+
+ alt {
+ /* MME originated S1AP PDU to S1GW */
+ [] as_s1ap_dpdu(pdu, S1AP_PDU_DIR_FROM_MME) {
+ f_ConnHdlr_tx_s1ap_from_mme(pdu);
+ }
+ /* eNB originated S1AP PDU to S1GW */
+ [] as_s1ap_dpdu(pdu, S1AP_PDU_DIR_FROM_ENB) {
+ f_ConnHdlr_tx_s1ap_from_enb(pdu);
+ }
+
+ /* MME originated S1AP PDU from S1GW */
+ [] as_ConnHdlr_s1ap_from_mme(pdu) {
+ f_UEMux_route_pdu({S1AP_PDU_DIR_FROM_MME, pdu});
+ }
+ /* eNB originated S1AP PDU from S1GW */
+ [] as_ConnHdlr_s1ap_from_enb(pdu) {
+ f_UEMux_route_pdu({S1AP_PDU_DIR_FROM_ENB, pdu});
+ }
+
+ /* UE subsciption procedures */
+ [] UEMUX_PROC.getcall(UEMux_subscribe_for_mme_ue_id:{?}) -> param(mme_ue_id) sender vc_conn {
+ f_UEMux_subscribe_for_mme_ue_id(vc_conn, mme_ue_id);
+ UEMUX_PROC.reply(UEMux_subscribe_for_mme_ue_id:{mme_ue_id}) to vc_conn;
+ }
+ [] UEMUX_PROC.getcall(UEMux_subscribe_for_enb_ue_id:{?}) -> param(enb_ue_id) sender vc_conn {
+ f_UEMux_subscribe_for_enb_ue_id(vc_conn, enb_ue_id);
+ UEMUX_PROC.reply(UEMux_subscribe_for_enb_ue_id:{enb_ue_id}) to vc_conn;
+ }
+ [] UEMUX_PROC.getcall(UEMux_unsubscribe:{}) -> sender vc_conn {
+ f_UEMux_unsubscribe(vc_conn);
+ UEMUX_PROC.reply(UEMux_unsubscribe:{}) to vc_conn;
+ }
+ }
+ }
+}
+
+}
To view, visit change 39850. To unsubscribe, or for help writing mail filters, visit settings.