PDU session establishment reject improvements

src/ue/sm/establishment.cpp

@@ -129,38 +129,25 @@ void NasSm::receivePduSessionEstablishmentAccept(const nas::PduSessionEstablishm
 {
     m_logger->debug("PDU Session Establishment Accept received");
 
-    if (msg.smCause.has_value())
-    {
-        m_logger->warn("SM cause received in PduSessionEstablishmentAccept [%s]",
-                       nas::utils::EnumToString(msg.smCause->value));
-    }
-
-    if (msg.pti < ProcedureTransaction::MIN_ID || msg.pti > ProcedureTransaction::MAX_ID)
-    {
-        // PTI is required for PDU session establishment request
-        m_logger->err("Received PTI [%d] value is invalid", msg.pti);
-        sendSmCause(nas::ESmCause::INVALID_PTI_VALUE, msg.pduSessionId);
+    if (!checkPtiAndPsi(msg))
         return;
-    }
-
-    if (m_procedureTransactions[msg.pti].psi != msg.pduSessionId)
-    {
-        m_logger->err("Received PSI value [%d] is invalid, expected was [%d]", msg.pduSessionId,
-                      m_procedureTransactions[msg.pti].psi);
-        sendSmCause(nas::ESmCause::INVALID_PTI_VALUE, msg.pduSessionId);
-        return;
-    }
 
     freeProcedureTransactionId(msg.pti);
 
-    auto& pduSession = m_pduSessions[msg.pduSessionId];
+    auto &pduSession = m_pduSessions[msg.pduSessionId];
     if (pduSession->psState != EPsState::ACTIVE_PENDING)
     {
-        m_logger->err("PS establishment accept received without requested");
+        m_logger->err("PS establishment accept received without being requested");
         sendSmCause(nas::ESmCause::MESSAGE_TYPE_NOT_COMPATIBLE_WITH_THE_PROTOCOL_STATE, pduSession->psi);
         return;
     }
 
+    if (msg.smCause.has_value())
+    {
+        m_logger->warn("SM cause received in PduSessionEstablishmentAccept [%s]",
+                       nas::utils::EnumToString(msg.smCause->value));
+    }
+
     pduSession->psState = EPsState::ACTIVE;
     pduSession->authorizedQoSRules = nas::utils::DeepCopyIe(msg.authorizedQoSRules);
     pduSession->sessionAmbr = nas::utils::DeepCopyIe(msg.sessionAmbr);
@@ -183,12 +170,6 @@ void NasSm::receivePduSessionEstablishmentAccept(const nas::PduSessionEstablishm
     m_logger->info("PDU Session establishment is successful PSI[%d]", pduSession->psi);
 }
 
-void NasSm::receivePduSessionEstablishmentReject(const nas::PduSessionEstablishmentReject &msg)
-{
-    m_logger->err("PDU Session Establishment Reject received [%s]", nas::utils::EnumToString(msg.smCause.value));
-    // TODO
-}
-
 void NasSm::abortEstablishmentRequest(int pti)
 {
     int psi = m_procedureTransactions[pti].psi;
@@ -199,4 +180,29 @@ void NasSm::abortEstablishmentRequest(int pti)
     freePduSessionId(psi);
 }
 
+void NasSm::receivePduSessionEstablishmentReject(const nas::PduSessionEstablishmentReject &msg)
+{
+    m_logger->err("PDU Session Establishment Reject received [%s]", nas::utils::EnumToString(msg.smCause.value));
+
+    if (!checkPtiAndPsi(msg))
+        return;
+
+    freeProcedureTransactionId(msg.pti);
+
+    auto &pduSession = m_pduSessions[msg.pduSessionId];
+    if (pduSession->psState != EPsState::ACTIVE_PENDING)
+    {
+        m_logger->err("PS establishment reject received without being requested");
+        sendSmCause(nas::ESmCause::MESSAGE_TYPE_NOT_COMPATIBLE_WITH_THE_PROTOCOL_STATE, pduSession->psi);
+        return;
+    }
+
+    pduSession->psState = EPsState::INACTIVE;
+    if (pduSession->isEmergency)
+    {
+        // This not much important and no need for now
+        // TODO: inform the upper layers of the failure of the procedure
+    }
+}
+
 } // namespace nr::ue
\ No newline at end of file

src/ue/sm/sm.hpp

@@ -74,6 +74,9 @@ class NasSm
     void onTimerExpire(nas::NasTimer &timer);
     void onTransactionTimerExpire(int pti);
 
+    /* Utils */
+    bool checkPtiAndPsi(const nas::SmMessage& msg);
+
   public:
     /* Interface */
     void handleNasEvent(const NwUeNasToNas &msg); // used by NAS

src/ue/sm/utils.cpp

+//
+// This file is a part of UERANSIM open source project.
+// Copyright (c) 2021 ALİ GÜNGÖR.
+//
+// The software and all associated files are licensed under GPL-3.0
+// and subject to the terms and conditions defined in LICENSE file.
+//
+
+#include "sm.hpp"
+#include <nas/utils.hpp>
+#include <ue/app/task.hpp>
+#include <ue/mm/mm.hpp>
+
+namespace nr::ue
+{
+
+bool NasSm::checkPtiAndPsi(const nas::SmMessage &msg)
+{
+    if (msg.pti < ProcedureTransaction::MIN_ID || msg.pti > ProcedureTransaction::MAX_ID)
+    {
+        m_logger->err("Received PTI [%d] value is invalid", msg.pti);
+        sendSmCause(nas::ESmCause::INVALID_PTI_VALUE, msg.pduSessionId);
+        return false;
+    }
+
+    if (m_procedureTransactions[msg.pti].psi != msg.pduSessionId)
+    {
+        m_logger->err("Received PSI value [%d] is invalid, expected was [%d]", msg.pduSessionId,
+                      m_procedureTransactions[msg.pti].psi);
+        sendSmCause(nas::ESmCause::INVALID_PTI_VALUE, msg.pduSessionId);
+        return false;
+    }
+
+    return true;
+}
+
+} // namespace nr::ue
\ No newline at end of file