BSSMAP_Emulation: Decode DTAP
It's quite cumbersome if the user of the BSSMAP_Emulation (the ConnHdlr)
will have to manually decode the DTAP in every BSSAP/DTAP message he
receives (and encode on the transmit side). Let's introduce a new
optional mode in which the DTAP messages are already decoded for
more convenient matching inside the ConnHdlr.
Change-Id: I35cd4ea78aca0ce7c7d745e082d7289882c11e81
diff --git a/bsc-nat/BSC_MS_ConnectionHandler.ttcn b/bsc-nat/BSC_MS_ConnectionHandler.ttcn
index 876d2ec..6efb15b 100644
--- a/bsc-nat/BSC_MS_ConnectionHandler.ttcn
+++ b/bsc-nat/BSC_MS_ConnectionHandler.ttcn
@@ -50,7 +50,9 @@
const BssmapOps BSC_MS_BssmapOps := {
create_cb := refers(CreateCallback),
- unitdata_cb := refers(UnitdataCallback)
+ unitdata_cb := refers(UnitdataCallback),
+ decode_dtap := false,
+ role_ms := true
}
diff --git a/bsc-nat/MSC_ConnectionHandler.ttcn b/bsc-nat/MSC_ConnectionHandler.ttcn
index b038ce5..0a06759 100644
--- a/bsc-nat/MSC_ConnectionHandler.ttcn
+++ b/bsc-nat/MSC_ConnectionHandler.ttcn
@@ -56,7 +56,9 @@
const BssmapOps MSC_BssmapOps := {
create_cb := refers(CreateCallback),
- unitdata_cb := refers(UnitdataCallback)
+ unitdata_cb := refers(UnitdataCallback),
+ decode_dtap := false,
+ role_ms := false
}
type enumerated MSC_State {
diff --git a/bsc/MSC_ConnectionHandler.ttcn b/bsc/MSC_ConnectionHandler.ttcn
index f683ef4..39b09f6 100644
--- a/bsc/MSC_ConnectionHandler.ttcn
+++ b/bsc/MSC_ConnectionHandler.ttcn
@@ -50,7 +50,9 @@
const BssmapOps MSC_BssmapOps := {
create_cb := refers(BSSMAP_Emulation.ExpectedCreateCallback),
- unitdata_cb := refers(UnitdataCallback)
+ unitdata_cb := refers(UnitdataCallback),
+ decode_dtap := false,
+ role_ms := false
}
type enumerated MSC_State {
diff --git a/library/BSSMAP_Emulation.ttcn b/library/BSSMAP_Emulation.ttcn
index 14174f8..dce8eb0 100644
--- a/library/BSSMAP_Emulation.ttcn
+++ b/library/BSSMAP_Emulation.ttcn
@@ -22,7 +22,7 @@
* Inbound Unit Data messages (such as are dispatched to the BssmapOps.unitdata_cb() callback,
* which is registered with an argument to the main() function below.
*
- * (C) 2017 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2017-2018 by Harald Welte <laforge@gnumonks.org>
* All rights reserved.
*
* Released under the terms of GNU General Public License, Version 2 or
@@ -30,6 +30,7 @@
*/
+import from General_Types all;
import from SCCP_Emulation all;
import from SCCPasp_Types all;
import from BSSAP_Types all;
@@ -38,6 +39,7 @@
import from MGCP_Types all;
import from MGCP_Templates all;
import from IPA_Emulation all;
+import from MobileL3_Types all;
/* General "base class" component definition, of which specific implementations
* derive themselves by means of the "extends" feature */
@@ -62,9 +64,42 @@
PDU_BSSAP bssap
}
+/* similar to PDU_BSSAP with DTAP, but DTAP is already decoded! */
+type record PDU_DTAP_MO {
+ OCT1 dlci optional,
+ PDU_ML3_MS_NW dtap
+}
+
+/* similar to PDU_BSSAP with DTAP, but DTAP is already decoded! */
+type record PDU_DTAP_MT {
+ OCT1 dlci optional,
+ PDU_ML3_NW_MS dtap
+}
+
+template PDU_DTAP_MT ts_PDU_DTAP_MT(template PDU_ML3_NW_MS dtap, template OCT1 dlci := omit) := {
+ dlci := dlci,
+ dtap := dtap
+}
+
+template PDU_DTAP_MO ts_PDU_DTAP_MO(template PDU_ML3_MS_NW dtap, template OCT1 dlci := '00'O) := {
+ dlci := dlci,
+ dtap := dtap
+}
+
+template PDU_DTAP_MT tr_PDU_DTAP_MT(template PDU_ML3_NW_MS dtap, template OCT1 dlci := *) := {
+ dlci := dlci,
+ dtap := dtap
+}
+
+template PDU_DTAP_MO tr_PDU_DTAP_MO(template PDU_ML3_MS_NW dtap, template OCT1 dlci := *) := {
+ dlci := dlci,
+ dtap := dtap
+}
+
+
/* port between individual per-connection components and this dispatcher */
type port BSSAP_Conn_PT message {
- inout PDU_BSSAP, BSSAP_Conn_Prim, BSSAP_Conn_Req, MgcpCommand, MgcpResponse;
+ inout PDU_BSSAP, PDU_DTAP_MO, PDU_DTAP_MT, BSSAP_Conn_Prim, BSSAP_Conn_Req, MgcpCommand, MgcpResponse;
} with { extension "internal" };
@@ -97,6 +132,7 @@
var charstring g_bssmap_id;
var integer g_next_e1_ts := 1;
+ var BssmapOps g_bssmap_ops;
};
private function f_conn_id_known(integer sccp_conn_id)
@@ -279,7 +315,25 @@
f_comp_store_cic(client, cic);
}
- CLIENT.send(bssap) to client;
+ if (ischosen(bssap.pdu.dtap) and g_bssmap_ops.decode_dtap) {
+ if (g_bssmap_ops.role_ms) {
+ /* we are the MS, so any message to us must be MT */
+ var PDU_DTAP_MT mt := {
+ dlci := bssap.dlci,
+ dtap := dec_PDU_ML3_NW_MS(bssap.pdu.dtap)
+ };
+ CLIENT.send(mt) to client;
+ } else {
+ /* we are the Network, so any message to us must be MO */
+ var PDU_DTAP_MO mo := {
+ dlci := bssap.dlci,
+ dtap := dec_PDU_ML3_MS_NW(bssap.pdu.dtap)
+ };
+ CLIENT.send(mo) to client;
+ }
+ } else {
+ CLIENT.send(bssap) to client;
+ }
}
/* call-back type, to be provided by specific implementation; called when new SCCP connection
@@ -292,12 +346,15 @@
type record BssmapOps {
BssmapCreateCallback create_cb,
- BssmapUnitdataCallback unitdata_cb
+ BssmapUnitdataCallback unitdata_cb,
+ boolean decode_dtap,
+ boolean role_ms
}
function main(BssmapOps ops, charstring id) runs on BSSMAP_Emulation_CT {
g_bssmap_id := id;
+ g_bssmap_ops := ops;
f_conn_table_init();
f_expect_table_init();
@@ -310,6 +367,8 @@
var BSSAP_Conn_Req creq;
var BSSAP_ConnHdlr vc_conn;
var PDU_BSSAP bssap;
+ var PDU_DTAP_MO dtap_mo;
+ var PDU_DTAP_MT dtap_mt;
var MgcpCommand mgcp_req;
var MgcpResponse mgcp_resp;
var BSSAP_ConnHdlr vc_hdlr;
@@ -402,6 +461,23 @@
BSSAP.send(ts_BSSAP_DATA_req(conn_id, bssap));
}
+ [g_bssmap_ops.role_ms] CLIENT.receive(PDU_DTAP_MO:?) -> value dtap_mo sender vc_conn {
+ var integer conn_id := f_conn_id_by_comp(vc_conn);
+ /* convert from decoded DTAP to encoded DTAP */
+ var octetstring l3_enc := enc_PDU_ML3_MS_NW(dtap_mo.dtap);
+ bssap := valueof(ts_BSSAP_DTAP(l3_enc, dtap_mo.dlci));
+ BSSAP.send(ts_BSSAP_DATA_req(conn_id, bssap));
+ }
+
+ [not g_bssmap_ops.role_ms] CLIENT.receive(PDU_DTAP_MT:?) -> value dtap_mt sender vc_conn {
+ var integer conn_id := f_conn_id_by_comp(vc_conn);
+ /* convert from decoded DTAP to encoded DTAP */
+ var octetstring l3_enc := enc_PDU_ML3_NW_MS(dtap_mt.dtap);
+ bssap := valueof(ts_BSSAP_DTAP(l3_enc, dtap_mo.dlci));
+ BSSAP.send(ts_BSSAP_DATA_req(conn_id, bssap));
+ }
+
+
/* Handling of MGCP in IPA SCCPLite case. This predates 3GPP AoIP
* and uses a MGCP session in parallel to BSSAP. BSSAP uses CIC
* as usual, and MGCP uses "CIC@mgw" endpoint naming, where CIC