mme: Implement missing UE attach steps

Related: OS#6294
Change-Id: Ib4a69aef40bf9dd17d640f650e459668f8415aaa
diff --git a/library/NAS_Templates.ttcn b/library/NAS_Templates.ttcn
index 45f5f8d..70561b3 100644
--- a/library/NAS_Templates.ttcn
+++ b/library/NAS_Templates.ttcn
@@ -1025,6 +1025,55 @@
 		}
 	}
 }
+template (present) PDU_NAS_EPS
+tr_NAS_ActDefEpsBearCtxReq(template (present) BIT4 bearer_id := ?,
+			   template (present) BIT8 proc_tid := ?,
+			   template (present) EPS_QualityOfServiceV qos := ?,
+			   template (present) octetstring apn := ?,
+			   template (present) BIT3 addr_type := ?,
+			   template (present) octetstring addr_info := ?) := {
+	protocolDiscriminator := c_EPS_NAS_PD_ESM,
+	ePS_messages := {
+		ePS_SessionManagement := {
+			pDU_NAS_EPS_ActDefEPSBearerContextRequest := {
+				ePSBearerIdentity := bearer_id,
+				procedureTransactionIdentifier := proc_tid,
+				messageType := '11000001'B,
+				ePS_QoS := {
+					lengthIndicator := ?,
+					ePS_QualityOfServiceV := qos
+				},
+				accessPointName := {
+					lengthIndicator := 0,
+					accessPointNameValue := apn
+				},
+				pDN_Address := {
+					lengthIndicator := 0,
+					typeValue := addr_type,
+					spare := '00000'B,
+					addressInformation := addr_info
+				},
+				transactionIdentifier := *,
+				negotiatedQoS := *,
+				negotiated_LLC_SAPI := *,
+				radioPriority := *,
+				packetFlowID := *,
+				aPN_AMBR := *,
+				esmCause := *,
+				protocolConfigOptions := *,
+				connectivityType := *,
+				wLANOffloadIndication := *,
+				nBIFOMContainer := *,
+				headerCompressinConfiguration := *,
+				controlPlaneOnlyIndication := *,
+				extendedProtocolConfigurationOptions := *,
+				servingPLMNRateControl := *,
+				extended_APN_AMBR := *,
+				extendedQoS := *
+			}
+		}
+	}
+}
 
 /* 8.3.4 Activate Default EPS Bearer Context Accept */
 template (value) PDU_NAS_EPS